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Apropos the Meissner Effect : how is a totally still magnetic field expelled from the interior of a superconducting body, when it is cooled below the transition temperature? From whence do the supercurrent elements obtain their impulse ; how can they suddenly become screening currents, without a cause?
Conversely, it is quite understandable that bringing a superconducting body into a magnetic field-- in this case the supercurrent elements obtain their impulse from a changing magnetic field, via the Lenz-Faraday Law. But in the above case, the magnetic field is absolutely still, and so cannot possibly provide the mechanism to set up surface screening currents.
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The inflation of the balloon is equivalent to the creation of the Cooper pairs and the condensate. This releases energy that does the work to "inflate the balloon". In the same way that a plastic bottle of water will swell and lift even a heavy weight above it when it freezes.
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Apropos the Meissner Effect : how is a totally still magnetic field expelled from the interior of a superconducting body, when it is cooled below the transition temperature? From whence do the supercurrent elements obtain their impulse ; how can they suddenly become screening currents, without a cause?
Conversely, it is quite understandable that bringing a superconducting body into a magnetic field-- in this case the supercurrent elements obtain their impulse from a changing magnetic field, via the Lenz-Faraday Law. But in the above case, the magnetic field is absolutely still, and so cannot possibly provide the mechanism to set up surface screening currents.
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The considerer above notes the London equations-- I mention the London equations, and their role, in my note here:
This follows on from a previous paper on the Constancy of the speed of light ;
Both of these are examples of what I call "mankind centric" science, where the cause is with the observers.
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Does "quadrupole" (Quadrupole-dipole), related to "Electrodynamic mechanism in SERS (in the case of, either noble metal nanoparticles or semiconducting nanoparticles)
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OK, about the "can we see it" part: the quadrupole-dipole part makes a band of a Raman spectrum more intense or may even show vibrations which are otherwise forbidden, but it does not create new vibrational modes.
I'm not sure what you mean with neglecting nuclear transitions, nuclear transitions are excited with gamma rays in Mößbauer spectroscopy which is way beyond the energy of any existing laser.
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Which protocols can be used for transformation of anaerobic bacteria from Azoarcus genus? So far I tried chemical transformation with CaCl2 buffer and electrotransformation with MOPS, but they didn't work. Any suggestions, tips & tricks?
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WOuld this be helpful
Please check this paper "Agr Quorum Sensing infuences the Wood‑Ljungdahl pathway in Clostridium autoethanogenum" 2021
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In the paper of Vladimir Onoochin
after analyzing the original works of Lorentz and Einstein:
"The Lorentz transformations of coordinates in expressions for electromagnetic fields defined in one inertial frame do not give Lorentz-transformed expressions for these fields in another inertial frame"
It is quite peculiar and tricky: considering (1) E,B --> E',B', as the experimentally verified transformation of the fields, by looking at it component by component, one is brought to believe that the fields underwent a Lorentz Transformation themselves.
It becomes quite obvious to think that also space and time should follow such transformations.
On the other hand, the transformation of coordinates X, t --> X', t' which allows (1) to occur, does not have the form of an LT. By applying the LT to the coordinates, the final form of the fields is not the right one.
He concludes: " ‘relativistic invariance’ of the Maxwell equations is caused – not by the corresponding transformation of coordinates – but by their Galilean transformations (8) and change in scales of x, y, z, t, "
The invariance of Maxwell equations is indeed guaranteed by Inertial transformations which keep the simultaneity invariant, not by Lorentz Transformations which keep the speed of light as an invariant.
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Dear Eric Lord ,
I well understand what you want to mean,
<<he seems to have regarded t′ (“local time”) as a mere computational device without any clear physical meaning.>>
actually what is quite likely devoid of a Phyiscal meaning, at the end of the day, is the resynchronization term vx'/c2 in
t'= gamma-1 t - vx'/c2
unless somebody properly operates resychronization, such thing cannot occur.
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The received wisdom is that quantum mechanics describes why the electron does not penetrate the proton. I find this statement unsatisfying as its is merely a description of an observation at best, with no explanation of physics, electrodynamics, kinetics or information of any kind. Has anyone ever tried using Maxwell?
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NO, there is none. Classically an electron moving in a circular orbit has acceleration, which means it should radiate, lose energy and eventually spiral into the nucleous. The reason for this stability is the uncertainity principle, the electron reacts to confinement by increasing the spread of its velocities, hence momenta, hence energies. If you do a rough calculation and substitute h/r for the momentum in the kinetic energy term, you will get an expression E(r)=h^2/2mr^2-Ze^2/r. For small r, the first term dominates and gives infinity. For large r, the second term dominates and gives 0 from the negative side. Hence there must be a negative energy minimum which you can get by taking the derivative.
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If anybody is dealing with Electro slag remelting, please explain.
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I am thinking about this question too. The used ESR slag is not homogeneous in composition. I saw some samples recently. I will do some analysis and then consider how to reuse them.
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i study about electrodynamic tether system
i don't calculate current-voltage equation (OML Theory)
i understand how to calculate boundary conditions but i don't know how to intagrate equation directly
please give me some solution
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Woojae Jang I suggest reading this article
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Hi, I have written a code for solving the Helmholtz-Maxwell electromagnetic equation using finite difference time domain (FDTD) method. There is not much material available online for this equation. All the algorithms available online or offline are based on Yee's leap frog method.
I have followed the book Computational electrodynamics by Taflov and a PDF by Prof. John S that is available online. Now when I follow Yee's grid then TFSF work very well but when I try to implement it on my code then it doesn't work at all. I'm following the same method to suppress the leftward traveling wave as discussed in these sources albeit with slight modification.
If someone has done it before and can help me on this then it would be of great help.
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Hello. Isn't the M-H equation the same as the Wave equation? That equation is discussed in Taflove 2nd Ed., Section 2.5. When you implement the Wave Equation and the FDTD equations, without separation into TF-SF, do you get identical results? What additional info about the Wave equation are you looking for? Why do you want to extract the SF (I assume SF=Field without Scatterer-Field With Scatterer)?
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I do not have anything to test but if you can point me in the right direction? Looking for what is the relative permittivity for the Felt fabric?
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Dear Meenakshi
Please, see the following reference. It is a study about many wearable material parameters:
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The refractive index is obtained owing to classical electrodynamics. Is there any way to know how much momentum the electron gains when light incident on a dielectric material? How does the momentum of the electron depend on the refractive index ?
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Here is a quantum theory of refractive index.
For a beautiful treatment of classical origin of refractive index, you may take a look at Feynman Lectures.
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Oleksii Kostenko The Metaverse AI has emerged as one of the most hotly debated subjects in technology and socioeconomics. The function of AI in the Metaverse entails mixing numerous technologies such as virtual reality, 3D animation, and blockchain, and many firms are already working on developing services for this new digital environment.
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For those that have the seventh printing of Goldstein's "Classical Mechanics" so I don't have to write any equations here. The Lagrangian for electromagnetic fields (expressed in terms of scalar and vector potentials) for a given charge density and current density that creates the fields is the spatial volume integral of the Lagrangian density listed in Goldstein's book as Eq. (11-65) (page 366 in my edition of the book). Goldstein then considers the case (page 369 in my edition of the book) in which the charges and currents are carried by point charges. The charge density (for example) is taken to be a Dirac delta function of the spatial coordinates. This is utilized in the evaluation of one of the integrals used to construct the Lagrangian. This integral is the spatial volume integral of charge density multiplied by the scalar potential. What is giving me trouble is as follows.
In the discussion below, a "particle" refers to an object that is small in some sense but has a greater-than-zero size. It becomes a point as a limiting case as the size shrinks to zero. In order for the charge density of a particle, regardless of how small the particle is, to be represented by a delta function in the volume integral of charge density multiplied by potential, it is necessary for the potential to be nearly constant over distances equal to the particle size. This is true (when the particle is sufficiently small) for external potentials evaluated at the location of the particle of interest, where the external potential as seen by the particle of interest is defined to be the potential created by all particles except the particle of interest. However, total potential, which includes the potential created by the particle of interest, is not slowly varying over the dimensions of the particle of interest regardless of how small the particle is. The charge density cannot be represented by a delta function in the integral of charge density times potential, when the potential is total potential, regardless of how small the particle is. If we imagine the particles to be charged marbles (greater than zero size and having finite charge densities) the potential that should be multiplying the charge density in the integral is total potential. As the marble size shrinks to zero the potential is still total potential and the marble charge density cannot be represented by a delta function. Yet textbooks do use this representation, as if the potential is external potential instead of total potential. How do we justify replacing total potential with external potential in this integral?
I won't be surprised if the answers get into the issues of self forces (the forces producing the recoil of a particle from its own emitted electromagnetic radiation). I am happy with using the simple textbook approach and ignoring self forces if some justification can be given for replacing total potential with external potential. But without that justification being given, I don't see how the textbooks reach the conclusions they reach with or without self forces being ignored.
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A revision with a more appropriate title is attached. The Conclusion section is specific about the difference between what is in this report and what is in at least some popular textbooks.
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I have a electro fenton system that cathode electrode is graphite and anode is FTO coated with a photocatalyst . when i want to increase current density to upper limit, suddenly deposited layer was being separated uniformly from FTO anode via oxygen releasing from anode surface .
anode surface pre treatment(degreasing with ethanol and functionalization with HNO3) was done before layer deposition and annealing after deposition . would you please help my how can i prevent from separation of deposited layer on anode surface?
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thank you very much
i experienced your comment a bout coating of FTO with thin layer of catalyst and also increasing annealing temperature until 470 degree C. and successfully was controlled cracking of coated film.
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A thin, circular disc of radius R is made up of a conducting material. A charge Q is given to it, which spreads on the two surfaces.
Will the surface charge density be uniform? If not, where will it be minimum?
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when I don't "see" the answer to a problem immediately, I find it sometimes worthwhile to play around with the help of a math program. For example, with integrals it replaces a heavy book like Gradshteyn, Ryzhik: Table of Integrals, Series, And Products, and if an integral cannot be solved symbolically, it can be solved at least numerically for a few cases.
Assuming a unit disk and using polar coordinates (r, φ), for a charge at a certain point (p, 0) on the surface one can split the surface into an inner disk with radius <= p - ϵ and an outer ring with inner radius > p + ϵ, for a small ϵ (and outer radius 1, of course). Then one can write an equation for the r component of the force (the φ component is zero due to symmetry) which takes into account the 1/d^2 dependence of the force (d being the distance between p and an arbitrary point on the disk) as well as the angle of the force. 2D integration over the inner disk and over the outer ring results in the forces exerted by both, and addition gives the total force. Please see the attached figure 1. Since this procedure involves no term expressing a dependence of charge density on location, it covers evenly distributed charge, and figure 1 refutes this idea: Except at the center, the force isn't zero, so the charge density would change (here, positive values stand for centrifugal forces and vice versa).
If the term to be integrated is expanded by a factor modeling a charge density dependent on r, then the results change accordingly. The correct term, 1/sqrt(1 - r^2) in the case of a unit disk, results in figure 2.
These notes by Ted Bunn might be of interest because they explain how to arrive at the correct term:
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I did a reaction but By changing the concentration of electrolyte leads to different product.
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Organic electrosynthesis is inherently environmentally benign technique because it uses the electron as a redox agent rather than chemical oxidants or reductants as in traditional chemistry. As such, electrosynthesis does not produce waste.Electrochemical synthesis is the use of electrical energy to drive chemical change; using electricity to replace toxic and costly chemical reagents. This allows cleaner and cheaper syntheses with greater production efficiency and at reduced cost.
It is the basis for the simplest forms of amperometric biosensors, where a current is produced in proportion to the oxygen concentration.
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Give an example where the electric field is zero at a point but divergence of the electric field is non zero there?
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Dear Spiros Konstantogiannis, thank you, I agree, it means the identity is independent of the type of gauge.
I just could not remember if the vectorial identity somehow could depend on the type of one of the 2 gauges for the case of electromagnetism.
Best Regards.
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Hello everyone,
I want to electro polymerize PEDOT:PSS using 0.5 M 3,4-ethylene dioxythiophene (EDOT, Sigma-Aldrich, USA) aqueous solution containing 0.6 wt% of poly(sodium 4-styrene sulfonate)(PSS, Sigma-Aldrich, USA). I found this in a paper (https://www.nature.com/articles/srep40332).
I found EDOT on the sigma-Aldrich website. But, when I was searching for poly(sodium 4-styrene sulfonate) as mentioned in the paper, I found many results for the search. I don't know which one to choose, and various molecular weights are mentioned. Can someone help me with that?
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Review -chemosensors Functionalization Strategies of PEDOT and PEDOT:PSS Films for Organic Bioelectronics Applications Gonzalo E. Fenoy 1 , Omar Azzaroni 1,2,*, Wolfgang Knoll 3,4 and Waldemar A. Marmisollé 1,*  Abstract: Organic bioelectronics involves the connection of organic semiconductors with living organisms, organs, tissues, cells, membranes, proteins, and even small molecules. In recent years, this field has received great interest due to the development of all kinds of devices architectures, enabling the detection of several relevant biomarkers, the stimulation and sensing of cells and tissues, and the recording of electrophysiological signals, among others. In this review, we discuss recent func- tionalization approaches for PEDOT and PEDOT:PSS films with the aim of integrating biomolecules for the fabrication of bioelectronics platforms. As the choice of the strategy is determined by the conducting polymer synthesis method, initially PEDOT and PEDOT:PSS films preparation methods are presented. Later, a wide variety of PEDOT functionalization approaches are discussed, together with bioconjugation techniques to develop efficient organic-biological interfaces. Finally, and by making use of these approaches, the fabrication of different platforms towards organic bioelectronics devices is reviewed. Keywords: functionalization; organic bioelectronics; organic electrochemical transistors; PEDOT; PEDOT:PSS; bioconjugation; biosensing
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options
1.Boron doped diamond
2.Titanium dioxide coated with platinum
3. Ruthenium Oxide
4. Iridium Oxide
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Dear Bibin K Suresh many thanks for sharing this very interesting technical question with the RG community. Unfortunately I'm not a specialist in this field of research as we work mainly in synthetic inorganic chemistry. However, there are several relevant literature eferences available which might help you in your analysis. For example, please have a look at the following potentially useful articles:
Electrochemical Removal of Ammonium Nitrogen and COD of Domestic Wastewater using Platinum Coated Titanium as an Anode Electrode
This paper has been published Open Access (please see the attached pdf file). the same is true for the following interesting paper:
Process Optimization of Electrochemical Treatment of COD and Total Nitrogen Containing Wastewater
(also attached)
The third paper is freely available as public full text on RG:
Removal of ammonia nitrogen in wastewater by indirect mechanism using electrochemical method with platinum electrode as anode
I hope this helps. Good luck with your research and best wishes, Frank Edelmann
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Some theories of physics require (not merely allow) magnetic monopoles. [See, for example, David J. Griffiths, Introduction to Electrodynamics, Fourth (Kindle) Edition (Cambridge University Press, Cambridge, UK, 2017.] But how can a theory that requires (not merely allows) magnetic monopoles be consistent with the fact that magnets with circular magnetic fields — and hence with no poles (neither a north pole nor a south pole) — exist? Two examples: (i) A horseshoe iron, alnico, or other permanent magnet bent into a circle, with the poles cold-welded together. (Cold welding is possible in a vacuum for surfaces planed very smooth.) (ii) A toroidal-solenoid electromagnet (with or without an enclosed iron core for increased strength). The magnetic field lines in such magnets are circular — and hence with no poles — neither a north pole nor a south pole.
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As I understand, your question is not about horseshoe magnet.
First of all, there is no problem with existence of circular magnetic fields even if there are magnetic monopoles (somwhere else). Such fields can be produced by electric currents. Simplest example of the circular magnetic field produced without magnetic monopoles is the field around the wire with electric current.
As for theories that require (or, at least, admit) existence of magnetis charges, their consistency with experimental data depends on the viewpoint.
For instance, there is an interesting theory of superluminal particles developed by Italian physicists (see e.g. Recami, E., & Mignani, R. (1974). Classical theory of tachyons (special relativity extended to superluminal frames and objects). La Rivista Del Nuovo Cimento Series 2, 4(2), 209–290).
According to this theory, superluminal velocity flips electric and magnetic fields, i.e. electric fields become magnetic and vice versa. Prticularly, superluminal magnetic charge will be seen as electric charge (i.e. the divergence of the electric field (div E) will be non-zero).
To undestand this, consider (again) the simplest example of magnetic field around the wire with electric current. In fact, this is the case of superluminal electric charge: it's time-like component (charge density in the wire) is zero, while space-like component (electric current) is non-zero. And, as we know, this "superluminal" electric charge produces magnetic field, not electric.
Similarly, superluminal magnetic charges (if exist) will produce electric field.
According to Recami & Mignani referred above, protons can be regarded as superluminal magnetic currents inside the proton. Since these currents are superluminal, they are seen as electric charges (not magnetic).
What are the reasons to think that currents inside the proton are superluminal? Well, according to experiments on inelastic scattering of electrons on protons, the number of proton constituents (termed partons) that scatter electrons is dependent on the reference frame. The faster the observer is moving with respect to scattering particles, the more proton constituents will be observed (you can read about this here: https://profmattstrassler.com/articles-and-posts/largehadroncolliderfaq/whats-a-proton-anyway/).
But according to Special relativity, this can only happen if proton constituents are moving faster than light. As you certainly know, slower-than-light objects can be at the same place at different times. Similarly, in Special relativity faster-than-light objects can be at different places at the same time. And the "number of places" where superluminal objects can be observed at the same time depend on the reference frame of the observer.
If we accept the idea of Recami & Mignani, we obtain very nice picture of the world with both electric charges (subluminal, inside electrons, muons and tau) and magnetic charges (superluminal. inside protons). But they both look like electric charges from our frame, hence we have an impression that there are no magnetic charges in nature.
I hope this is a good example of the theory that admits magnetic charges and is consistent with our experimental observations.
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Respected sir
Now i am working for written review article under the topic of Electro chemical machining process which is most important in UCM. This is my first effort for the preparing review articles so i need procedure for writing review article and
1.what are the ethics must be follow during review article reparation....?
2.source available ways and how to utilize available resources with effective .....
Kindly share your suggestions successfully accomplishing my target....
Greatest Regards
S.Sathishkumar
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I design a plant for producing caustic soda and chlorine from electrolysis of brine (salt from desalination plants)
How can i use aspen plus in simulate the electro chemical cell (membrane cell) •??
📷
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You can read this paper:
Aspen Plus model of an alkaline electrolysis system for hydrogen production
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say, when we take a simple titration of any compound to induce some change and study the change what we can see the change if it is faster change in the optical parameter or change in absorption or energy change or when we do its electro chemical analysis the changed species will be faster response as its electron transfer, what will be faster ? or both the methodologies will be different in kinetics due to different technical aspects and parameters? optical corresponds to the technique spectrophotometric methods . and more elaboratively from which technique we can get better electron transfer kinetics or the accurate degree of minimal observable change.
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Optical changes are faster
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I setup an electro blotting experiment for overnight wet transfer using Tris glycine based transfer buffer at 20V. Next day , to my surprise there was lots of rusty froth in the tank. Also their was deposition of heavy rust on negative electrode. I've performed several O/N transfers earlier, but this was the first time I observe such reaction. Did any body experienced it ? what could be the possible reasons behind?
Blotting details:
PVDF 0.22 uM membrane
Transfer buffer: Tris Glycine with 10% methanol
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Dear Shezaib Siddiqui
Western Blot Transfer Methods | Thermo Fisher Scientific - US
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I am working on metal removal process simulation. Can anyone help?
Specifically speaking, Wire electro discharge machining, creation of plasma channel in dielectric fluid between two electrodes and removing material from positive electrode through generated spark.
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Sorry for the late reply.... Hope you got it by now?
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Could anyone recommend a good textbook to study about Green Function in classical electrodynamics? Thank you.
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For the behavior of refractive space-dependent 3D electromagnetic waves using Green Function formalism in continuous media, the subject was addressed in chapter 6 of the monography:
Methods of Quantum Field Theory in Statistical Physics, (1963) by Abrikosov, Gorkov, and Dzyaloshinski. Dover NY.
Best Regards.
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I have tried doing ebsd but it is not giving a lot of un indexed points. So I dont know if the unindexed points are finer alpha titanium or beta titanium. During electro polishing the softer beta phase is getting etched off giving unindexed points on the IPF map .
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Dear Ketan,
Correct me if I am wrong, but in case you are just interested in the volume fractions of α- and β-phase in your alloy (and if we are not talking about (partial) martensitic structures with retained β-phase or structures in which you have extremely narrow β-regions), shouldn’t one be able to do a simple metallographic approach, e.g. by using one of the point-grid-methods?
After normal grinding and polishing etch the sample with e.g. Kroll’s reagent to make the two phases visible. Take images (depending of the microstructure and the accuracy you need use optical microscopy or SEM, high resolution SEM images might even resolve extremely fine β-laths), binarize the image (e.g. α white, β black) and count the number of black and white pixels (high accuracy) or use a point grid and count the points. In case, high-resolution SEM-images are needed and hence the investigated area per image is small, take a larger number of images to improve the statistics.
In case, you need to do EBSD, I would recommend using vibration polishing as the final polishing step as this minimizes the retained deformation and should, thus, reduce the number of unindexed regions. In case, this still fails, the use of hard X-rays might be advisable, as in contrast to standard XRD also very small volume fractions of phases can be detected.
Kind regards, Carsten
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Relation between electrostatic based problem and time harmonic electrodynamics problem.
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Dear Thomas Cuff, my doubt is for the analysis of the time-harmonic electromagnetic field, how can we take electrostatic behavior like inductance and capacitance into account. As the field behavior is completely different and wavelength is comparable with the physical dimension of the device, is it sufficient by considering capacitance per unit length or inductance per unit length? Whether we can calculate the field correctly by this approach.
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water splitting
Graphitic layer
metal
electro catalysis
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Amravati Singh Now every things completely change. You said: if metal coated with graphite layer and it means core-shell structure. Well I must explain the mechanism of the water splitting reaction for you if you are asking about metal-doped graphene catalysts. We have two half reaction in water slitting prosses:
1) 2 H+(aq) + 2e− → H2(g)
2)2 H2O(l) → O2(g) + 4 H+(aq) + 4e−
The oxidation reaction is the bottleneck of the water splitting prosses. The metal doped graphene act as a catalyst for the oxidation reaction. The metal oxidize by light or electricity or chemical oxidant like CAN and metal loses electrons and holes are formed. Now the metal site is ready to accept the H2O or OH- as a ligand. Then a radical coupling or water nucleophilic attack occurs that forms O2(g) and the metal reduce to the former oxidation state.
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How can we calculate extinction, scattering and absorption cross section using FDTD?
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Dear Shamjid,
Follow the instruction below to simulate the extinction, scattering and absorption cross-sections
1. Define your geometry.
2. Add material property from the database available under Lumerical or click here to get more materials.
3. Define your simulation region and add other parameters just mentioned in the link below and then simulate.
4. To plot all the cross-section spectrum you need to create .lsf script file that will read the output data from .fsp file and plot it into a separate window.
Hope it helps !!!
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According to Einstein-Rosen bridge theory, shortcuts in space time where if galaxies or multiverses come close to each other, due to excess increase in electro magnetic waving some fructures like holes or tubes, not to be confused with Black holes, form as shortcut tunnels in space time where the observer can see the destination he will be arriving if he goes into the hole when he looks into the worm hole. Having strength as a theory, somehow the worm holes must be detectable, but they are not. What do Physicists think? Are worm holes detectable?
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A wormhole has never been observed either directly or indirectly, but wormholes do exist in the sense that they arise in solutions to Einstein's general relativity field equations. What that means for those of us who don’t deal in Jacobian matrices every day is that we can break down the universe into its many different parts and then use mathematical equations to describe how those pieces fit together.
Those field equations are like the scaffolding or that the universe is built upon. The equations that describe how general relativity or gravity works don’t require that wormholes exist but they do allow for their existence. In other words, one possible solution to the general relativity field equations is a wormhole connecting two points in spacetime.
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The Plasma Dispersion effect changes the real as well as the imaginary refractive indices. Although the amount of them are different, there must be some effect of the loss part in modulator response to an RF signal. Are there some articles investigating this effect in high speed electro optic modulators?
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Amin, Rubab, Can Suer, Zhizhen Ma, Ibrahim Sarpkaya, Jacob B. Khurgin, Ritesh Agarwal, and Volker J. Sorger. "Active material, optical mode and cavity impact on nanoscale electro-optic modulation performance." Nanophotonics 7, no. 2 (2017): 455-472.
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My question is caused by one curious fact of the electrodynamics.
It is commonly accepted opinion that the electromagnetic fields can at least formally be decomposed onto the rotational and irrotational components. For the electric field of the classical charge being in arbitrary motion is seems to be obvious, namely, the radiated fields are transverse and therefore the rotational, the bound fields are longitudinal and therefore the irrotational.
But:
1. There is no example of such a decomposition of the E field of the classical charge if its law of motion is known;
2. The analogue of Helmholtz's proof of the theorem isn't extended to the electrodynamics. At least, no proof of this theorem is given in the textbooks.
Regarding p. 1, it is easy to give the counter-example, when the decomposition of the E field is impossible (the attached file).
But what is a reason of the absence of the analogue of Helmholtz's proof of the theorem isn't extended to the electrodynamics?
I suggest that because this theorem belongs to the mathematics, some mathematical obstacles should exist to prevent the extention of the theorem to the electrodynamics. What obstacles?
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Dear Vladimir,
There are a number of papers that deal with the Helmholtz Theorem for electrodynamics as opposed to electrostatics or magnetostatics. Probably the best one I've seen is by A.J.P. Davis from 2006 (pdf attached). The classical Helmholtz Theorem describes the behaviour of a field at a given instant in time, and does not describe how the field evolves with time since there are no time derivatives in the original theorem, only spatial ones (div and curl). It is therefore necessary to extend the Helmholtz Theorem in the manner that Davis describes in his paper to account for time-dependence. This results in a more generalised form of the theorem that involves a time derivative as well as div and curl spatial derivatives. One recovers the original form of the Helmholtz Theorem from this generalised form when the time dependence is removed. In addition, one must ensure that causality is satisfied which requires the use of retarded quantities in the generalised formulation. This is essential to accurately represent the fields generated by moving, and in particular, accelerated charges. The works of the late Oleg Jefimenko are also closely related to this topic.
Regards,
Ray Simpkin
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Dear Sirs,
Everybody knows plane and spherical wave solutions of Maxwell equations, e.g for decaying plane wave E=E0*exp(-kx)*cos(w(t-x/v)). But seems to me they give the unreal situation that the wave amplitude is nonzero at different points of space at given time moment. Could you advise the experiment or natural phenomenon which produces such a wave in nature?
Maybe we have infinte speed of the EM interaction? Do you know any real solution of Maxwel equations which exists only in one space point at the given time moment? Maybe using delta function? Or maybe there is my mistake?
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Nice Dear Joaquin Diaz-alonso
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The main question is:
What is Truth and Proof in Science?
What other scientific arguments are needed for the truth in science?
Actually, the uploaded preprints (see the project “Presentation of the scientific evidence for the nullity of the special theory of relativity”):
1. One-way measurement of the speed of light - the factual analysis
2. Michelson-Gale-Pearson experiment - the factual analysis
3. Sagnac experiment – the factual analysis
4. Michelson-Morley experiment - the factual analysis
not only prove that the speed of light is not the same for all frames of reference, but in the first section is presented a solution of all the "unexpected" and "inexplicable" results of experiments related to the behavior and measurement of the speed of light and carried out within our local time-spatial region, … and without of paradoxes.
5. In "On the Electrodynamics of Moving Bodies - the factual analysis of the article" is shown exactly where and how the erroneous claim “the speed of light is the same in all inertial frames of reference” is applied and actually rejects with arguments special theory of relativity.
6. The preprint "On the fundamental tests of the Special theory of relativity" reveals the essence of all the fundamental tests of SR.
What else is necessary for the truth to exist in physics?
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Karl Popper :
In so far as a scientific statement speaks about reality, it must be falsifiable; and in so far as it is not falsifiable, it does not speak about reality.
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Mass is transforming in energy activated by "c" as factor. Should this mean mass is some kind of "electrodynamical" phenomenon, e.g. some highly convoluted field?
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It is the unbalanced repulsion of the constituent volume elements of the charge of an accelerating electron caused by its distorted field that gives rise to the electron’s inertia and inertial mass.
This is as per the classical perspective of the electromagnetic mass theory.
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Any suggestions on what dielectric material to be used for metamaterial
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1) A 3 mm-thick felt substrate (with a relative dielectric constant of 1.3 and a loss tangent of 0.044) and a 0.17 mm-thick ShieldIt Super conductive textile from LessEMF Inc.
2) Flexible polyethylene terephtalate (PET) film can be used as substrate in GHz.
3) See the following paper:
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It seems that the moon is getting farther away from Earth. Yet, storms are getting more violent. Why? Do these ferocious storms (tornadoes, hurricanes, rain-wind-thunder-lightning storms) occur when the moon is closest to Earth?
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Thanks for your reply; however, I am unable to open the links you sent. Perhaps you might just briefly indicate their content. In any case, I appreciate your efforts and I wish you a Happy New Year for 2020.
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For HRV analysis I would like to use Kubios Standard. I recorded ECG with BrainVision Recorder and get .eeg files which cannot be importet into Kubios directly, as the Standard version only supports .txt, .dat, .csv and other file formats specific to Poloar Electro, Suunto or Garmin devices.
Right now, my solution was to set Markers for the R spikes using BrainVision Analyzer's "ECG Marker" Solution and then export these Positions in a .csv file. This I can import into Kubios.
Does anybody know of another way to directly import the raw data into Kubios?
Any advice is much appreciated, thank you!
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Thank you Ty Lees for your suggestion!
I just have to wait for my system administrator to set up EEGLAB for me, I'm excited to try it out!
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In electrodynamics, it is stated that the magnetic force cannot do work. The explanation of it is simple - magnetic force that acts on the charge is always perpendicular to the charge’s incremental displacements.
But it is obviously that in all electric motors, the magnetic force is responsible for rotation of the armature. So the magnetic force produces work.
I suggest that there is some 'gap' in correct description of the systems where the units move due to magnetic forces. An example is schemes of different magnetic 'perpetuum mobile' and without calculations, it is hard to convince the author that this device cannot give over-unity.
The question: How to describe work of the magnetic force in terms of the microscopic electrodynamics in the correct way?
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In thermodynamics, the expression of work due to the magnetic field depends on the material in question. For paramagnetic materials it has an expression, and for another type of material the expression varies, I don't remember the details. In the loop experiment, the magnetic work comes from the torque over the loop, the loop when rotating in an external magnetic field, produces a variation of the magnetic flux, that variation produces an electromotive force in the loop and is responsible for the work there . An additional electric field is generated inside the loop and the f.em. You have to keep the electric voltage constant. If the coil has no charge battery, a current that decays due to joule effect is produced.
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  • We are using the an LCMS system with electro spray ionization (waters’ SQD2). Our signals in a certain method decrease sharply with sequential sample injections due to obstruction of the cone aperture (where charged droplets are drawn to by voltage); once we take out the cone from the instrument, clean it, and pu it back- signals go back up.
  • Apart from purer solvents and reduced sample concentration, is there anthing in the tuning of the MS that can better focus the droplets into the cone aperture (cone voltage/gas flow/somthing else) without compromising signal intensity?
  • thanks!
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NO. The problem is not related to MS "tuning" so much as it is related to your method conditions. HPLC Method optimization for MS analysis is critical to obtaining reliable, accurate results and has the advantage of requiring the least amount of general maintenance.
  • For example: Non-optimized LC-MS conditions often result in large accumulations of material on the source parts (= more frequent maintenance and cleaning, higher variability in signal over time and inaccurate results). If the gas flow rates are too low, the heating temperature too low, the liquid flow rate too high, the amount (conc) of additives too high, sample overloaded.... any/all of these things may contribute to more accumulation of material on the source.
  • Learning how to optimize a LC-MS (or LC-MS/MS) system takes many years of practical experience using many types of different samples. It is a time consuming process that first requires a high quality HPLC method, followed by a step-wise optimization of all MS parameters to achieve accurate results.
High quality LC/MS methods carefully optimize all of the conditions & settings used for: heating, gas and liquid flow, ionization parameters plus utilize ultra-high purity chemicals and solvents in the method. *Generally speaking, the lower the flow rate, the less liquid that has to be removed by the system (so less noise and less material to accumulate). Narrow ID columns are commonly used to help in this respect. The method itself also contributes greatly to the results. If you have any large amounts of unwanted material early in the run, then the use an in-line diverter valve with make-up flow (e.g. CS3040, "LC-MS Contamination Minimizer"; aka: "LC-MS Watchdog") to divert this material to waste, and not to the source. Better sample clean-up methods (either in-line or done at the bench) also may contribute to cleaner components too.
We also tend to see some client's choose non-volatile mobile phase additives in the solutions, which are of course not advisable, and will surely result in problems/damage to the system so it is a good idea to review all chemicals used for applicability with the LC-MS method.
" Popular LC/MS and HPLC Volatile Mobile Phase Buffers"; https://hplctips.blogspot.com/2014/06/popular-hplc-volatile-mobile-phase.html ].
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Here's the topic: according to classical electrodynamics, accelerated charges radiate (see Larmor formula).
However, if we take the strong equivalence principle seriously, a charge in free fall does not radiate, whereas a charge being blocked by free fall (e.g. by being statically put on a table) doesn't.
Reminder: the weak equivalence principle in simple terms says: all particles follow the same spacetime path in free fall.
The strong equivalence principle goes even further to say: whatever your experiment is: you cannot distinguish locally between acceleration and gravity ("local" is key here).
Therefore in the following gedanken experiment, when you drop an electron from a large height towards earth ground (and when it falls freely) it does not radiate. Whereas, when you put it on your kitchen table, and there it lies, it does radiate. Ergo: as anticipated, classical electrodynamics is only valid in the absence of gravitation! No big news here...
I am pointing this out because:
- I do not see many GTR texts mentioning this gedanken experiment, let alone discussing it thoroughly
- the text by Rindler ("Essential Relativity") delivers an unsatisfactory and superficial discussion, although Rindler is otherwise an excellent text, albeit not for beginners
- it illustrates very strikingly the implications of the strong equivalence principle and deserves a more scrutinous analysis
Does anyone know of any papers calculating the radiation power of charged particles in curved spacetime which are not in free fall?
Does anyone know of a paper doing a thorough analysis on the backreaction on spacetime by the radiation emitted?
Thanks to everyone in advance!
Oliver
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Now being transferred to cold regions of my State, i observed that people ( Hotel Industry ) are these days installing DCI technology base Sewage Treatment Plant ( STP) rather than Biological section bases STP. The common statement/advantages i observed ( feedback ) as is that: 1. Easy in operation, 2. Less sludge generation ( Negligible). 3. No much technical staff is required 4. better results in final outlet of STP due to extreme cold whether and sufficient to handle to jerk load rather than maintaining BIo -Mass in both these two problems.
Whereas i personally have less knowledge about DCI technology so i have some doubts that :1. may be some amount of metal we are giving back to environment?? ( as degeneration of electrodes) 2. what will be exact mass balance and electro- chemistry over there in the Reactor??
So if some someone has comparisons or study paper on these two please share.
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Bruno Peeters you are right
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Anyone having any thoughts on how to get more accurate results?
My results are matching fairly well on low frequencies (4 to 15 hz) , and for finding the resonance frequencies (only 10 % or less different, and should get less with better experimental data later…), however at higher frequencies the plots diverges. I try to find relevant literature and other help online, but there are very limited literature available that are useful.
Attached you can find my experimental FRF. . The setup is a beam with a piezo patch attached to it. An accelerometer attached to the fixed end of the beam measures the base acceleration imposed by an electrodynamic shaker.
In the FRF,
EXP-denotes experimental FRF using Welch’s method (built into MATLAB). The three other graphs represent different ways of applying damping in ANSYS, where the two last (with alfa and beta) are Rayleigh damping coefficients.
Anyone having any experiences or any thoughts on how I can get ANSYS to be more realistic? Or maybe something is just fundementally wrong wrong with my experimental setup.
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Hi Simon. I have seen something similar. It seems to me that this digression between the theoretical and experimental results is because of the dynamic behaviour of the shaker itself which you may not have accounted for in your model. I suggest that inorder to make the simulated results more realistic, you have to consider the deformation of the shaker which you may have assumed rigid. Remember the shaker has its own natural frequencies and a finite stiffness. Hope this helps.
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I am a phD student and since I started, I was using ferrocene carboxylic acid for CV and impedance scans, but now I started to use Ferri ferrocyanide in order to try the redox couple with a new polymer. The problem that I am having at the moment is that I am not be able to get a proper CV shape (as you can see in the Fig 1) in the bare gold. I tried:
1. Different current and potential
2. Checked the holders and connections
3. Use external counter, external reference and external working electrode to check the reaction in the internal reference and counter on chip.
4. Different scan rates,
5. Remove oxygen in the solution.
6. Use different concentration of ferri ferro and PBS.
7. Clean the surface with acid
8. Square wave voltammetry.
After try all this options is happening the same all time but just in the internal working electrode (if I use external one the scans are perfect. Another people in my lab were trying ferri ferrocyanide in the past and looks like they were having the same problem as me and them decided to use another type of ferrocene. But at the moment I think that if with a commercial electrode the solution works (fig 3), it should be the same with the internal electrode on the chips that we use.
When I did Square wave voltammetry, I Could realise that there are appear different peaks when I use the same electrode in different time (fig 4). And each one of the electrodes has different peaks. But what is weird is that each time its different on the same electrode, which means that there is a type of reaction happening on the surface.
Can anyone help me to understand what is happening here? I think that in the surface of the electrode there is ‘’something’’ that can be detected using ferri ferro but not with ferrocene carboxylic acid (because the reaction is mask for the groups OH during the oxidation of carboxylic groups).
I use a concentration of 1.5 mM of ferri ferrocyanide in PBS, but as I wrote before I tried different concentrations (of ferri ferro and PBS) and nothing works with the internal electrode but it works with the external working electrode (so the solution it’s not the problem in my opinion). Also I was reading about electro oxidation of methanol or ethanol or some surface with wax layer and the behaviour is a little bit similar, but I am not an expert on this…
Thanks in advance for your time and I hope get help on this.
Regards
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I am a little confused by your "ferri ferrocyanide couple" Are you adding both ferricyanide and ferrocyanide to your solution? If not, which? If there is only ferricyanide, I would describe it simply as a ferricyanide solution.
Your CV looks almost as if you have a lot of ohmic drop in the solution (or film). The current is small but perhaps your film is reacting to the ferricyanide and ferrocyanide and becoming resistive. Even if the current is small, it is still 20x larger than the current with the ferrocene carboxylic acid. What if you dropped your concentration by 10-20 fold. This would help if ohmic drop is occurring.
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I'm looking for software (ideally free to use) which can perform fragment orbital DFT (FODFT) for calculating diabetic electronic coupling matrix elements (electro transfer integrals)? I'm currently using the ADF package but for the molecules I'm interested in it appears to be quite inefficient due to the use of Slater type orbitals.
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Hi Thomas, the nice thing about STOs is that typically you don't need that many. It could therefore in fact be faster than Gaussians. At least for GGAs. The 4c integrals are tricky with Slaters and hybrid functionals could indeed be slower. Usually transfer integrals and couplings, however, may be reasonably accurately predicted with a GGA. I've seen the PW91/TZP xc + basis set combination in quite a few papers. See also: https://www.scm.com/applications/organic-electronics/electron-and-hole-mobilities-in-organic-electronics/
Also check out some papers benchmarking different methods:
Hope this helps!
(Let us know at support@scm.com if you need any help with the ADF calculations)
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I am working on the preparation of graphene using electro-exfoliation of graphite. But I do not have RAMAN, SEM, or TEM. But I do have a spectrofluorometer in the lab I work in. Can this instrument help with the characterization?
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Spectrofluorometry will give you information about the fluorescence of the materials. Graphene-like materials are non-fluorescent but when oxidized (GO) they can emit a signal at a certain wavelength.
Usually you would, indeed, use other techniques like RAMAN spectroscopy, XPS, XRD...
However it is possible to visualize "the strong fluorescence quenching effect" of graphene based, single atomic layer carbon sheets with a common fluorescence microscope by applying a dye doped polymer coating. According to the last paper attached [Visualizing Graphene Based Sheets by Fluorescence Quenching Microscopy. Jaemyung Kim, Laura J. Cote, Franklin Kim, and Jiaxing Huang*
Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, USA].
The following papers could also be interesting for your study.
best regards,
Marie B.
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What is the purpose to require that the laws of physics be the same in all so-called inertial frames? On one hand it is natural to suppose that the basic laws, such as laws of mechanics and electrodynamics, are equally valid in every part of the Universe. It seems that almost all scientists believe in the unity of the Universe. But on the other hand such a belief is not very useful unless we have the power to confirm or deny its validity. For example, we can't test the validity of fluid mechanics on a planet 100 ly far from the Earth. Can we? All we can say is that the electromagnetic waves coming from far planet to us are pretty much the same as the EM waves we produce and use in our Earth-bound laboratories. That's all we can.
Imagine two identical copies of a system--laboratories--where we test mechanical waves. The systems are isolated, as much as possible, one from another, but are moving relative to each other with constant velocity v. In each system we would test a wave equation--in one system the equation is expressed with (x,t) coordinates, and in the other system with coordinates (x',t') (spatial and temporal coordinates). It is a simple math to show that the wave equations have the same form, but if we relate the coordinates as x'=x-vt & t'=t, the wave equation changes its form. The same will happen if we use Lorentz transformation, simply because the speeds of mechanical waves are different from the speed of light in vacuum. But, why we need to do that--to express our equations in the coordinates from some other system? Is it not enough to state that the laws governing the mechanical wave are the same? We already have two equal equations. It is true that we can find linear transformation, which is neither Galilean nor Lorentz, preserving the form of the equations in two systems, but for what purpose we should do that?
The bottom line is this--we don't need any theory of relativity. Any theory of relativity is useless and brings only confusion into physics.
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I suppose that this issue relies on fundamental role of the hystorical Galilean invariance issue, that is that laws and solutions must be the same in any inertial reference system. After GR theory this assumption can be relaxed but in classical mechanics it is still useful. However, also in the GR an assumption of "inertial frame" is somehow implied by the Lorentz transformation.
Why are you stating that any theory of relativity introduces confusion?
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Einstein stated that “The same laws of electrodynamics and optics will be valid for all frames of reference for which the equations of mechanics hold good”. In general, one of the main principle of SR is that "the laws of nature are the same for all inertial reference frames". Is this statement true?
One simple counter example refutes the above statement. Consider the law of the equality of the angles of reflection and incidence, say, when an ideal-elastic ball is thrown with a specific angle at a flat wall.
The reflection law is not true if the ball movement is studied from a different inertial frame. For example, if the experiment is observed by someone who is moving with the relative speed of v parallel to the reflection flight of the ball, the angle of reflection is always the same for any angle of incidence. The latter angle depends on the relative speed between the frame and the observer, v.
In general, the angle of reflection can be smaller, equal or larger than the angle of incidence if observed from different inertial reference frames. Please see section 2.1 (page 4) of the attached article for illustrations and more details.
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"Pythagoras's theorem only works in three dimensions."
The Pythagoras theorem works in all Euclidean spaces of dimension D>=2. It can even be been extended to infinite dimensional Hilbert spaces. The notion of cross product can be generalised to every finite-dimensional space, as the wedge operator ^ of Grassmann (exterior) algebra. It can be defined on spaces where no metric is defined, i.e. where the Pythagoras does not make sense. But additional properties, like the * operator, can be defined for metric spaces.
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Actually the gate contact is my last step in fabrication and would like to know about which from the following is the best process for fin topology, Evaporation, Sputtering, and Electro deposition .and what is the tests that should be carried out after the deposition to check the quality of gate deposition?
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sputtering
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For sustaining my PhD thesis I need to publish 1 or more articles with ISI impact factor (total ISI value 5). I have the experimental results from my previous job and I don't have the possibility to publish trough institution, so I have to publish them myself. The field is (electro)chemistry with aplication for food analysis (MSG). Do you know any journals with low costs for publishing an article (maxim 150 $) or even free?
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This is strange, I have been publishing in Elsevier journals for a very long time (and also in electrochemistry), but I never paid ...
At the same time, there are not so many electrochemical journals with an impact factor of more than 5, I know only ELECTROCHIMICA ACTA (WOS - 5.116) and JOURNAL OF POWER SOURCES (6.945). Even JOURNAL OF THE ELECTROCHEMICAL SOCIETY has IF by WOS 3.662. Impact factors by Scopus are different, but not too much (5.01, 7.00 and 3.48 respectively).
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How is it possible? What physics is behind it?
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Dear Dr. Khripov:
Matching High permittivity with low dielectric loss
Both questions should be approached with significant careful. See, there are no rule and several exceptions.
If a homogeneous and single phase ceramic is the prototype material of this analysis, we should have grain and grain boundary regions, in which bulk or grain really interest.
The concept of High permittivity and low dielectric loss match when specific defects are further engineered in crystallographic way. In this sense, such defects are represented as sub-levels in gap.
The parameter dielectric loss is ascribed to electrical conduction; in fact a low level electric current is operational, with direct effect under aging of material.
The defect associated to development of high permittivity; in a broad sense are intrinsic and extrinsic defects that are not involved with long range moving carrier, electrons, but with charge density and electron-lattice kind coupling. Here, typically a new set of defect with distinct level in gap are formed.
On the possibility
Both phenomena are ascribed to distinct type of defect and its eventual interaction with crystalline lattice. In a gross manner, crystalline structure with more low symmetry, complex structures with great set of distinct crystallographic sites, ferroelectrics and materials that exhibits combinations of these characteristics is further candidate.
On the necessary physics
Materials Physics combined with Physical of Dielectrics and further characterization techniques, as Impedance spectroscopy or Dielectric spectroscopy.
In addition, as comment, major part of condition to attain the perfect response of material should involve advanced techniques of ceramic processing.
with best regards
Marcos Nobre
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I need to do ECM process on metal matrix composites. where i can do it? any one suggest me.
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What is the form/dimensions of the samples?
Can you provide any further information on the metal matrix composite?
Best regards,
Marie B.
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This will help us to push vehicles at the speed of light
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For best efficiency you need to reflect the light back where it came from, this is twice as efficient as absorbing it, and more efficient than scattering it in lots of directions. If you reflect the light in some other direction than directly back it will deflect the vehicle sideways a bit too.
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i am trying to do the electro optically tunable pulse compression , using second harmonic generation in bulk BBO crystal , for that i need to define to independent electric field vectors in fourier space to solve my coupled wave equations . if some one has any idea of how to define two independent electric field electric field vectors in fourier space using matlab please assist.
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Dear Asim,
In the paper that you attached, E1, and E2 are fundamental and harmonic fields. So if you represent E1 as gaussian at frequency w, E2 is also gaussian at frequency 2w.
In your code above, there is no information about the frequency in the field.
It should be something like:
E1= sqrt(Pi) e^(i*w*t-i*beta*z) e^[ (-t/T0)^2]
where beta is the propagation constant.
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electric flux density  is equal to (numerically ) to the charge per area .....
but what are those lines ?? , the electric field strength is represented by lines .... however such lines do not  exist ..... eventually is there a particle that mediates magnetic flux, electric field strength or electric flux  .... eg protons mediates charge ...etc
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Electric Flux Density, D, is a conceptual/graphical vector field that we use to get a “feel” for a complicated electric field made by source charges. What is exactly an electric flux, as you ask, is called a flux line. A flux line represents the trajectory a positive test charge would take if placed at that point, or the force a positive test charge would experience if placed at that point.1 Flux lines aren’t real, they’re just useful for visualization, and the number of them that emanate from a charge is arbitrarily set; in SI units, 1 flux line will emanate from 1 C.2
I would also like to point out that the answer given by André Michaud is verbatim the definition of electric current, and must be a misunderstanding of your question.
1. from Introduction to Electrodynamics by Griffiths
2. From Elements of Electromagnetics by Sadiku
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In case of O/W emulsions containing non ionic surfactant stabilized by using a phase inversion temperature technique . Does, the magnitude of the zeta potential will reflect the stability of emulsion?
I.e if my zeta potential is near to zero i.e, - 4 or -5. Do we need to consider the magnitude of zeta potential(above -30 and + 30 mV) to tell that emulsion is stable.
In what type of stabilization mechanisms such as steric stabilization, steric repulsion and electro kinetic stabilization. we need to consider the magnitude of zeta potential.
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The concept of ZP is somewhat irrelevant as answered by John, above. You may also consult with the paper "Stabilization of Oil-in-Water Emulsions with Noninterfacially Adsorbed Particles", where a mixture of zwitterionic surfactant and silica particles is used to stabilize an emulsions.
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I am looking for a textbook about electroanalytical chemistry. may someone provide it to me? thanks in advance
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also try this book Analytical Electrochemistry, by Joseph Wang
One of the nice book to start with!
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I found this particular materials (FeTiO3/Fe2TiO5) focused on PEC water splitting system
i found very less DSSCs efficiency even less than 1%, it is lower than pure TiO2 why it is happen.
but in the the same kind of materials shows higher efficiency in PEC water splitting, how it is happen?
from few papers due to higher recombination rate and band position of materials reduces the DSSCs efficiency. but in the case of PEC water splitting this concept not matched ha how it is to be like this?
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I agree with Pom Kharel .
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The Theory of Relativity is incorrect because the force of the interaction of two charges depends on the distance between the charges and on their relative velocity. Dimensions, time and mass do not depend on the velocity of movement of the charges.
All the phenomena of the electrodynamics of moving bodies are calculated simpler and more precisely with the help of a force that depends on distance and velocity [1] - [4], than with the help of the Theory of Relativity.
References
1. Smulsky, J.J. 1994. The Electromagnetic and Gravitational Actions (The Non-Relativistic Tractates). Novosibirsk: "Science" Publisher. 225 p. (In Russian). http://www.ikz.ru/~smulski/ElGrVz2.pdf.
2. Smulsky, J.J. 1999. The Theory of Interaction. Novosibirsk: Publishing house of Novosibirsk University, Scientific Publishing Center of United Institute of Geology and Geophysics Siberian Branch of Russian Academy of Sciences. 293 p. (In Russian) http://www.ikz.ru/~smulski/TVfulA5_2.pdf.
3. Smulsky, J.J. 2004. The Theory of Interaction. Ekaterinburg, Russia: Publishing house "Cultural Information Bank". 304 p. http://www.ikz.ru/~smulski/TVEnA5_2.pdf.
4. Smulsky, J.J. 2014. Electrodynamics of moving bodies. Determination of forces and calculation of movements. Saarbrucken, Germany: "Palmarium Academic Publishing". 324 p. ISBN 978-3-659-98421-1. (In Russian). http://www.ikz.ru/~smulski/ElMovBdJ.pdf.
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Dear Joseph,
I reached the very same conclusion. You will find on pages 2 to 4 of this recently published paper the exact reason why SR is incompatible with electromagnetism, which should confirm your conclusion.
SR and GR alike are unable to account for the existence of electric charges.
Best Regards
André
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The recoil force of radiation is known for spontaneous emission (for the radiation of an accelerating charge or dipole), when the photon field is empty. Is there any difference when stimulated emission is considered? Would it be enough to add an external force to the original radiative reaction-force without changing the original form of the radiative reaction?
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more precisely:
" The net change regarding momentum and energy exchange with EM field
is identical to SPONTANEOUS emission, isn't it?"
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Respected sir
The different type of electrolyte used in ECM Process which electrolyte is best for ECM Process and if we are changing electrolyte the conductivity of work piece i will be change ........
it is possible or impossible ..........?
i am eagerly waiting for different answer and ideas
Greatest Regards
S.Sathishkumar
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Dear Sathishkumar,
If you investigate the literature you can see that different type of electrolytes causes different output parameters (MRR, surface roughness, oversut etc.) due to workpiece material. Three different electrolyte types can be used ECM;
1- Sludging (NaCl,NaNO3,etc.)
2-Non sludging (HCl etc.)
3-Mixed (NaNO3+HCl)
In addition i have to say that NaCl type electrolyte is the hardest one to control the machining accuracy. But most MRR can be achivied with this type of electrolyte.
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Respected sir
Greetings
ECM Process only suitable for conductive materials ,if material low conductivity some crucial process used for convert conductive materials then we will involve Machining by ECM But now my doubt is in case My materials is fully non conductive,if it is possible for convert Conductivity of materials in as per required limitation of ECM ......?
Best Regards
S.Sathishkumar
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No
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Light is electro magnetic wave. So, it should bend in strong magnetic field. Is it insignificant or no effect?
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Berend, The double helix alignment is a magnetic line of force. The principle behind it is that the electrostatic force of attraction that acts between the electrons and positrons in the background dielectric sea is channeled along the double helix. I.e. magnetic attraction is simply electrostatic attraction between electrons and positrons in a particular arrangement. Magnetic repulsion on the other hand acts at right angles from magnetic lines of force due to centrifugal force acting in the equatorial plane between two adjacent rotating dipoles.
In the case of electric current, if positive particles are sources in the fundamental aethereal fluid that comprises electric current, then they will be pushed along with the flow. Negative particles being sinks, will eat their way upstream in the opposite direction. But the primary electric current itself will be the uni-directional aether flow. It will be a hydrodynamical momentum and in many cases it will arise from the velocity field of an electric field. Rotating dipoles are in fact dipolar aether vortices and the circulation current/momentum A nowadays known as the magnetic vector potential is in fact Maxwell's displacement current.
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Collective effects are evident in billions and billions of particles or entities in physics, such as In lasers, electromagnetism [1], superconductivity, critical mass in nuclear physics, physics of fluids, thixotropic and other non-newtonian effects, fusion and fission, binding energy, gravity, and quantum mechanics.
There are applications also in maths. We discussed its application in social movements, where statistics is not used, nor psychology, but a causal model is introduced, based on physics of fluids and collective effects.
The problem is that a system made of billions of billions of particles or entities, as usual in physics of natural systems, is much harder to study, for example, in quantum behaviour or even classical.
In network theory, comes the example of 6 degrees of separation. Now, in physics [2,3], comes the example of 10 photons. Studying quantum behaviour of particles is much easier with fewer particles, so the fact that phase transitions occur in these small systems means we can better study quantum properties such as coherence.
Could we start to see behaviour of collective effects with 10 electrons or less? Can we use them to better study coherence also in non-quantum behaviour? What is the lower limit?
[1] Carver Mead, Collective Electrodynamics: Quantum Foundations of Electromagnetism,
[3] Driven-dissipative non-equilibrium Bose–Einstein condensation of less than ten photons, https://www.nature.com/articles/s41567-018-0270-1
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I am aware of at least one highly nontrivial collective effect with 3 entities: Efimov states. Much simplified, it's existence of trimer where there is no dimer.
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In his book "Electrodynamics" Einstein gave an example of Lenz. Lenz obtained the Schwarzschild metric using the Lorentz transformations.
How far are the possibilities of such methods?
For example, I used the semiclassical method to get the gravitational field of a point source from Einstein's principle that the energy of the gravitational field is the source of the gravitational field.
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I do not get the point. What exactly do you mean by "non-standard way"? There are many different alternative models to GR. Are you looking for another alternative model? For instance, in GR matter and energy warps spacetime, and the curvature of spacetime around any mass represents the source of gravity.
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I need to study the effect of very high power short duration electro magnetic pulses on electronic circuits. Which computational method may be suitable ? Time domain or frequency domain ? and which method in the respective domain ? Please give your suggestions.
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None of the above. At that range, you have to deal with near field photons, and the quantum tunneling effects of these high energy photons across the silica barriers. You need to look deeply into the Near Field Effect and Quantum Tunneling, or everything you measure will seem like a mess of anomalies. Also, the high energy photons will cause other anomalous effects, such as providing energy for electrons to also quantum tunnel across the silica barriers.
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I would like to measure the concentration of the metal( Gold, Copper, Silver, Platinum and Rhodium) ions in the acidic electrolyte.
Is there are device measure/ monitor the concentration of the ions?
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If your concentration is in the range ppb to ppm non electrochemical techniques such as ICP-MS or ICP-OES work best, above this i.e. ppm and higher XRF is useful. Both techniques enable you to unambiguously determine metal ion concentration. Electrochemical techniques centred mostly around stripping voltammetric techniques can be challenging if the solution contains more than one metal ion and will require much more work for calibration
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Famous Lienard- Wiechert Potentials are given by:
V(R, t) = (1/ 4.%pi. eplison0) qc /(rc - r.v)
A(R, t) = (v/ c2) V(R, t)
Where, v is the retarded (earlier) velocity vector of the charge.
The formulae were derived in "Introduction to Electrodynamics" by Griffiths; considering change in apparent length of a moving train . While the same were derived in "Feynman Lectures" by considering overlapping volume elements of the moving charge.
However, if the methods of these derivations were applied to the general case where observer were also moving, with some non-zero velocity u; it looks as if the potentials would still remain the same; i.e. independent of u.
If this is correct, the retardation effect would not vanish even if the charge & the observer both were moving with the same velocity, in same direction (i.e. in the same inertial frame); where it should vanish.
Do really, the Lienard- Wiechert Potentials depend upon "Absolute" velocity of the source; or relative velocity between the source & observer ?
Is any other derivations are available where this general case has been considered ?
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Fixing what I said before: you only see radiaton effect if the particle is accelerated.