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  • Shangmin Xiong asked a question in Particle Size:
    How may I explain the shift in peak positions in radial distribution functions?

    I am doing classical MD simulations of crystalline-like FCC nanoparticles at finite temperatures. When analyzing the peak positions of the averaged radial distribution functions over 1000 snapshots at equilibrium, I found the positions of the first peaks (bond length) decreased as T increased, while those of the second, third and fourth peaks increased as T increased. The same trends were observed at two particle sizes. The calculated average bond length (pair-wise distances within cutoff) increased as T increased. So I couldn't think of a reason for the opposite trends of 1st peak vs. others. Would you please shed light on this issue? Thank you very much.

  • Rajan Vishwakarma added an answer in Steam Turbine:
    What are the design considerations to address higher thermal stresses for steam turbine casings at elevated temperature Zone (steam inlet) ?

    Apart from physical properties of material, To reduces higher thermal stresses in steam turbine casings especially in steam inlet, wall thickness optimisation, relaxing the extant of constraints, reducing the temperature differential across the wall may be the criterion.
    Can anyone comment on this or if any other criterion or way to reduce thermal stresses.

    Rajan Vishwakarma

    Thanks Mr. Chhaya and Balakrishnan for commenting.

    I have read TBC(Thermal Barrier coating) in gas turbine blade. Do you have any literature regarding TBC for steam turbine casings because by applying TBC on casing surface, change of temperature across the wall can be reduce.  

  • Mark Hopkinson added an answer in Micro-CT:
    How do I wash off iodine or PMA from whole rat heart?

    I stain the rat heart with Lugol's iodine or PMA for micro-CT. I want to re-stain the same heart with for Picro Sirius Red.​

    I stain the rat heart with Lugol's iodine or PMA for micro-CT. I want to re-stain the same heart with for Picro Sirius Red. How do I wash iodine or PMA off from the whole heart. The heart has been dehydrated gradually by 30%, 50% and 70% alcohol when it is stained with PMA and iodine.

    Mark Hopkinson

    Remove the iodine using 96% ethanol as sodium thiosulfate has been shown to effect sample density. PTA can be removed using NaOH so this method may be effective with PMA. Here's the link for the associated paper

  • Norhanani Othman asked a question in Spectrophotometry:
    If our sample have less colour and cannot apply the spectrophotometry analysis, what we should do to analysed the sample?


  • Gianrocco Tucci asked a question in Arousal:
    If it is true that man does not occupy a central position in the cosmos, however he seems to have a privileged position, What would such privilege be?

    According to Professor Tanzella-Nitti in the process of understanding cosmos human presence does not seem to play any significant role. In fact, the small importance of its cosmic coordinates - geometric, chemical and biological - would not seem to have any influence on the structure and evolution of the universe as a whole, if it is evaluated against the background of large-scale cosmological entire physical universe. However, man occupies a privileged position because the fundamental parameters that determine both the structure and the physico-chemical laws of the universe, were the very ones needed to be able to support life, and possibly intelligent observers.

    Going into the details, the Australian physicist Brandon Carter introduced the formulation of the Anthropic Principle with two different variants, weak and strong. In the first case it is stated that the measure of some specific cosmological parameters can be only the one compatible with the existence of observers; in the second, that the universe must possess only those properties and parameters whose values admit the presence of observers. Carter legitimized the "novelty" of the perspective, pointing out that the introduction of the Principle in science was simply related to its predictive capability, similar to what happens to other principles or theories commonly used in physics or astrophysics.

    Were the English cosmologist John Barrow and the American physicist Frank Tipler with their work ‘The Anthropic Cosmological Principle’ (1986) to theorize in a broad and systematic mode the Anthropic Principle proposing three precise versions, which will condition nearly all the subsequent debate on the subject. According to their formulation of the Weak Anthropic Principle (WAP), "the observed values of all physical and cosmological quantities are not equally likely, but have values limited by the condition that there are places in which the carbon-based life can evolve and by the condition that the universe is old enough to have been able to give rise to such forms of life "(Barrow and Tipler, 1986, p. 16).

    The debate is a sign of a major interdisciplinary hermeneutics breakthrough that the Anthropic Principle has aroused and continues to arouse. It is a reflection of sciences on the cosmos that is obliged to call again into question the role of the knowing subject, not in the simple context of a specific measure theory or a general interaction subject / object, but as part of a global question on the nature and meaning of the universe as a whole. Therefore, we share the opinion of the French philosopher J. Merleau-Ponty (1984), that the Anthropic Principle represents a significant epistemological shift in the philosophy of science of the twentieth century, thanks to its ability to re-open the discussion on the role not accidental that man plays in understanding the physical universe, forcing the physical cosmology to revisit some of its principles as recognized intertwined with issues of metaphysical nature, finally reopening the way for a new integration between the natural sciences and humanities (cfr. also Masani, 1984 and 1996) .

    Reflection begins by noting the importance and the critical values of the four constants of nature that regulate the intensity of the interaction of the four fundamental forces, respectively: gravitational, electromagnetic, nuclear electroweak and strong nuclear, showing in the first instance as the structure of each body - from the elementary particles, to the biological molecules, to the living beings, up to the planets, stars, and galaxies - have a structure of dimensions (dimension values and mass), which depends significantly from them. In particular, the mass M or the size R of the physical bodies can be expressed as a function of a mass, or of a typical size, multiplied by the four constants of nature elevated to a suitable power.

    This means that every traceable structure in nature be in a diagram log R - log M, within a narrow well-defined band. This result does not highlight any particular “anthropic” condition but simply points to the importance, for the structuring of the cosmos, of the constants of interaction. It should be noted that the four constants are dimensionless, that is, do not depend on the particular system of measurement chosen, but represent pure numbers. The value of the relation between two of them represent the relative intensity of the forces in question, adjusting the way in which, varying the distance of two bodies, one is predominant relative to the other (it should be remembered that they may act in a competitive manner, as it happens for example, for positive protons of an atomic nucleus, between the electromagnetic force, that tends to reject charges of the same sign, and the strong nuclear that on very short scale tends to draw them mutually). In the expression of their formula, the constants of nature in turn depend on other mathematical constants (like p) or physical (not dimensionless), such as the proton mass mp, the electron charge, and the gravitational constant G , the Planck constant h, the speed of light c.

    The values of the constants of nature that regulate the intensity of the interaction of the four fundamental forces, are in some way "congenital" to the coming into being of the universe.

    Various authors have rightly highlighted that the WAP appears as a Principle scientifically founded, but philosophically irrelevant (that is, it is emphasized the tautological reading, or otherwise of simple reformulation of a status de facto), while SAP is presented as a Principle scientifically unfounded but of a very strong philosophical content.

    It seems to us to be an appropriate distinction, both at the level of the analysis of sciences and at the logic of inference, although it is understandable that at other levels of reflection some authors tend to emphasize a certain continuity between the two formulations. That the distinction between WAP and SAP should in any case, at least generally, remain, is also suggested by the observation that in strictly scientific terms the weak formulation of the Principle asserts that the conditions and coincidences observed are necessary but not sufficient for the appearance of life, while the strong formulation states that it must be necessary and sufficient conditions

  • Hossein Javadi added an answer in Invariant Theory:
    Did Einstein obtain field equations directly from the principle of equivalence?

    "THE MEANING OF RELATIVITY” is a description of General Relativity by Einstein.


    Einstein wrote: "It is evident that the formulation of the general theory of relativity assumes a generalization of the theory of invariants and the theory of tensors; the question is raised as to the form of the equations which are co-variant with respect to arbitrary point transformations. The generalized calculus of tensors was developed by mathematicians long before the theory of relativity. Riemann rst extended Gauss's train of thought to continua of any number of dimensions; with prophetic vision he saw the physical meaning of this generalization of Euclid's geometry. Then followed the development of the theory in the form of the calculus of tensors, particularly by Ricci and Levi-Civita. This is the place for a brief presentation of the most important mathematical concepts and operations of this calculus of tensors". Page 68.

    Many have claimed that in 1915 Hilbert discovered the correct field equations for general relativity before Einstein but never claimed priority. Following article shows that this view is in error.

    Belated Decision in the Hilbert-Einstein Priority Dispute

    According to the commonly accepted view, David Hilbert completed the general theory of relativity at least 5 days before Albert Einstein submitted his conclusive paper on this theory on 25 November 1915. Hilbert's article, bearing the date of submission 20 November 1915 but published only on 31 March 1916, presents a generally covariant theory of gravitation, including field equations essentially equivalent to those in Einstein's paper. A close analysis of archival material reveals that Hilbert did not anticipate Einstein. The first set of proofs of Hilbert's paper shows that the theory he originally submitted is not generally covariant and does not include the explicit form of the field equations of general relativity.


    If equivalence principle was origin of general relativity, how Einstein have obtained Field equations?

    Hossein Javadi

    Dear Hans
    Seems we need a new definition of graviton.

  • Jirka Holler added an answer in Dissolved Oxygen:
    PKa of oxygen?

    Can one determine pKa of oxygen - O2? Or how does dissolving  of oxygen in pure water affect pH?

    Jirka Holler

    I though so, but could you please explain this. We use pure oxygen for our fermentation process (pulse dosing, so there some oscillation around set point). pH rises with every oxygen dose (just about 0.5). There is bicarbonate buffer, so is it possible that oxygen supplement removes carbon dioxide from medium, so the pH rises? Can it be like this?

  • puneet pal singh Cheema asked a question in Piping:
    Is it advisable to purchase water gems and sewer gems software for academic purpose?

    We are planning to purchase water gems and sewer gems software for our department for research purpose with 250 pipes. We are little bit confused about the capabilities of these software.

  • Ahmed Sabah Kareem added an answer in 3D Printing:
    Can someone provide help of explanation of my FTIR test for PLA ?

    I bought  commercial white PLA from market to do 3D printing research , to make sure of this material is PLA , I tested it by FTIR attached here but I do not know if it is PLA or not where there is more than two types of PLA ;PLLA , PDLA and  PDLLA . IF the material processed by white  die  and plasticizer , will these materials appear in FTIR test ? 

    + 1 more attachment

    Ahmed Sabah Kareem

    Dear John Hiltz  , 

    Thaks for sharing us your knowledge , yes we used Kbr and PLA as powder .

  • Dr showkat Maqbool asked a question in Designs:
    Can we call sampling procedures as field designs?

    can we call sampling procedures as field designs?

  • Jagadevappa S Patil added an answer in Bioavailability:
    How to improve bioavailability of natural lipophilic compounds?

    We want to improve bioavailability of plant based lipophilic compound. Please let me know various pharmacological mechanism to improve kinetics.



    Jagadevappa S Patil

    Dear Shankar,

    Both of above scientists explained in a very fantastic ways. Along with the above suggestions, you can also try to enhance the solubility of the compounds by mechanochemical activation (Co-grinding) technique and other established solubility enhancement approaches. This can help you to intern enhance the bioavailablity of your intended natural compounds. Hope you will become success in this.

  • ra Sii added an answer in Flood Modelling:
    How can I assess flood capacity from a fragility curve?

    I have created fragility curves for two types of buildings. now i want to create flood capacity map from thesis fragility curves. Kindly share if this is possible to assess capacity of flood from fragility curves?

    ra Sii

    Its flood resistance capacity. 

  • Syed Arif Rizvi asked a question in MATLAB:
    Can anybody know Matlab codes for optimal placement of DG ?

     I am one of new Matlab user . My Objective Function is to reduce the reactive power loss(refer to attachment ) .

    I got a code for simple objective function val = (x - 15)^2 + (y - 20)^2 , I run this and observe the results  and now i am quite familiar with PSO working on matlab . But 

    My objective is quite complex so please share program for reactive power loss minimization if any one have. Similar program will also help me in this regards 

  • Roozbeh Hesamamiri added an answer in Strategic Management:
    What experiential exercises can be used for teaching strategic management?

    I would like to know what experiential team-based exercises are recommended for teaching strategic management in Msc classes. For example, to introduce vision, mission, strategy, values, policies, etc.

    Roozbeh Hesamamiri

    If possible, please specify any class materials.

  • Stam Nicolis added an answer in Gravitational Field:
    Is the non locality of the gravitational field energy a serious problem for General Relativity (GRT)?



    "Although there is no room for such a thing in the energy–

    momentum tensor T, it is clear that there are situations where a ‘disembodied’

    gravitational energy is actually playing a physical role.

    Imagine  two massive bodies (planets, say). If they are close together (and we can

    suppose that they are instantaneously at rest relative to each other), then

    there will be a (negative) gravitational potential energy contribution which

    makes the total energy, and therefore the total mass, smaller than it would

    be if they are far apart.  Ignoring much tinier energy effects,

    such as distortions of each body’s shape due to the gravitational tidal field

    of the other, we see that the total contributions from the actual energy–

    momentum tensor T will be the same whether the two bodies are close

    together or far apart. Yet, the total mass/energy will differ in the two cases,

    and this difference would be attributed to the energy in the gravitational

    field itself (in fact a negative contribution, that is more sizeable when the

    bodies are close than when they are far apart)." 


    The same problem was also rised by Thirring, Kalman and Feynman in the FGT theory, they inserted the gravitational energy in the tensor equations...

    It is a problem of paramount importance which prevents the General relativity theory from describing any motion in which the hamiltonian is time dependent or rather in case of non isolated systems, or in case of non stationary interactions between different bodies.

    The attempt to model a free falling body in a gravitational field for GRT seems impossible.

    GRT has been tested  only for static or stationary systems where there is not a net exchange of energy (excluding gravitational radiation)

    Don't we need another GRAVITATIONAL THEORY which includes the results give by GRT in order to explain with a better accuracy the simple phenomenon like the free falling of a mass in a gravitational field?

    Stam Nicolis

    That special relativity expresses the equality between 4-vectors is, of course, a mathematical fact. As is the statement that 4-vectors transform in a certain way under Lorentz transformations.  That one example of such an equality is provided by Maxwell's equations, is another. There isn't any ``physical reality'' that's described by trivial mathematical mistakes; there may be different, mathematically consistent descriptions, that experiment can distinguish, which happens between Newtonian mechanics and relativistic mechanics, just as there can be many, apparently, different, mathematically consistent descriptions, that can be proven to be equivalent and, thus, no experiment can distinguish, as happens when writing Maxwell's equations in covariant form or not.

  • Ali Rahmat asked a question in Publisher:
    Journal easy to accepted?

    Dear Professor and researcher, Good Afternoon. I am Ali Rahmat,master student of Gifu University. I have paper draft about soil water content (soil moisture) in different forest type. for my graduation I need to publish paper in Journal with indexed by ISI The Thomson Reuters, but because limited my experience and budget to publish I do not know which journal easy to accepted. If you have experience about that, can you share with me please?

  • Anup Kumar Bandyopadhyay added an answer in Dielectric Constant:
    How do I calculate effective dielectric constant for a coplanar waveguide (CPW) and other related structure including antennas?

    How do I calculate effective dielectric constant for a coplanar waveguide (CPW) and other related structure including antennas? Can you give me some reference.

    Anup Kumar Bandyopadhyay

    Thank you all for your kind cooperation. Regards


  • Hediye Ashoori added an answer in Abaqus:
    In dynamic analysis of tunnel in abaqus, where am I supposed to impose acceleration–time histories of earthquake ?

    the model that i used is a 2D deformable one. and i use contact element between tunnel and soil for simulating interaction.

    Hediye Ashoori

    dear Alessandro

    can you explain more about periodgram ?

    thank you

  • Carlos Araújo Queiroz added an answer in Solvents:
    How can I recognize the features of a solvent?

    When we want to use a solvent or a mixture, we want to predict and evaluate different types of molecular interaction through some features of the chosen solvent.

    Like, polar or apolar, protic or aprotic, etc..

     Please help me with reference, book or link, etc …

     I need to write a chapter in my thesis manuscript and use these concepts for discussion and interpretation of the studied liquid systems.

     Thank you in advance.

    Carlos Araújo Queiroz

    Yet another useful solvent's handbook: Ernest W. Flick (Ed.), "Industrial Solvents Handbook", 5th ed., Noyes Data Corp., Westwood (New Jersey; USA), 1998.

  • Mustafa Aydin added an answer in Sleep:
    What is the average number of hours of sleep for good performance of a child of 6-10 years?

    What is the average number of hours of sleep for good performance of a child of 6-10 years?

    I need to know the average number of hours of rest for children aged between 6 and 10 years, to make a good recommendation to a team of category U10

    Mustafa Aydin

    The recommended amount of sleep per night for kids aged 6-10 is 10-11 hours, and for older kids is 8.5-9.5 hours.

  • Thirumaya Prabhu Balakrishnan added an answer in ANSYS Workbench:
    How do I rectify this error regarding a contact problem in static structural analysis in ANSYS workbench?

    An internal solution magnitude limit was exceeded. please check your Environment for inappropriate load values or insufficient supports. Also check that your mesh has more than 1 element in at least 2 direction are present.

    Thirumaya Prabhu Balakrishnan

    If there is contact problems in modeling and its produce error during your mesh operation. Thereby you can try to refine the issue over this during your part preparation. you can use the tool such as imprint the parts. it will reduce your contact problems. you make the interfaces such as contact interface as per your structural parts nature.

    Best of luck! to be successful 

  • Vyanaktesh Balajirao Yannawar added an answer in Plagiarism:
    Which is the best anti-plagiarism checking software?
    To test my documents strength.
    Vyanaktesh Balajirao Yannawar

    Turnitin is best

  • Magdalena Toda added an answer in Unitary Operators:
    Are there any unitary operators on the Bergman space?

    Are there any unitary operators on the Bergman space $A^2(D)$?

    Magdalena Toda

    I recommend reading this paper:


    Best wishes!

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: For D the open complex unit disc with normalized area measure, we consider the Bergman space L 2a (D) of square-integrable holomorphic functions on D. Induced by the group Aut(D) of biholomorphic automorphisms of D, there is a standard family of Weyl-type unitary operators on L 2a(D). For all bounded operators X on L 2a(D), the Berezin transform X is a smooth, bounded function on D. The range of the mapping Ber: X → X is invariant under Aut(D). The "mixing properties" of the elements of Aut(D) are visible in the Berezin transforms of the induced unitary operators. Computations involving these operators show that there is no real number M>0 with; M||X||∞geq ||X|| for all bounded operators X; and are used to check other possible properties of X. Extensions to other domains are discussed.
      Proceedings of the American Mathematical Society 10/2012; 140(10):3445-3451. DOI:10.1090/S0002-9939-2012-11440-6
  • Sujeet Mishra asked a question in Writing Reports:
    Can philosophical and historical research called qualitative research?

     We know that the researches have classified on many views i.e. on the basis of knowledge- fundamental and applied research, on the basis of nature of knowledge- philosophical, scientific and historical research, on the basis of data- qualitative and quantitative research, on the basis of process-survey, experimental, quasi experimental, ex post facto,case study, ethnography, field study,follow up research etc. on the basis of analysis process- analytical, synthactical, logical analysis research etc. on the basis of purpose descriptive, evaluation etc. but when a researcher write the report of thesis many confusion comes at the time because few basis of overlapped like my question.   

  • Rajesh P Barnwal added an answer in Devices:
    All IoT devices are device constrained ?

    hello people 

    i have a question, when people talk about IoT they always mentioned constrained devices but from my point of view ...

    i saw that not all IoT devices are device constrained .

    so any one can make this point more clear ?

    thank u in advance 

    Rajesh P Barnwal


    As u rightly noticed that all IoT devices are not constrained. If u take example of things like TV, Refrigerators, Vehicles etc., they are not constrained by any means. These devices can become a part of IoT but has no constraints in terms of energy, computation power or most of the time bandwidth as well.

  • Hazim Hashim Tahir added an answer in Complicity:
    It is said that ignorance is bliss!

    Is it really a bliss in the complicated complex world.

    Hazim Hashim Tahir

    Dear Colleagues,

    Good Day,

    I do not agree with this phrase "ignorance is bliss", I agree 100% with what "Ingrid Holtby and Jim Rohn" once said, please , see.... 

    + 1 more attachment

  • Magdalena Toda added an answer in Numerical Calculations:
    How can I calculate the improper integral using Matlab?

    Dear Prof.,

    We have an integral in which we have singularity. We try to use Matlab for numerical calculation. However, We have not found the correct way to calculate the integral. We use trapz or cumtrapz. However we can not remove the infinities in the integral. Please let you suggest me about this problem.

    Thank you for your suggestion

    Magdalena Toda

    I agree. It depends on the type of improper integral. Basically you can use the tools at:


    adapted to your case. Careful, depending on the took you use, you can get crazy answers based on the machine limit, so make sure what you get makes sense. :-) Best of luck!

  • Yd Koh asked a question in Laser Technology:
    Can I drill the hole with diameter 0.6 to 1.0mm through glass which is 3.2 mm thick and soda-lime silcate?

    I want to know whether the glass can be drilled with hole diamter of 0.6 to 1.0mm using laser technology.

    The glass is 3.2 mm thick and soda-lime silicate.

  • Jacques P. Beaugrand added an answer in Quantitative Methodology:
    Is it possible to use both within-subject and between-subject design for a same experimental work?

    Both within-subject and between-subject designs have advantages and disadvantages. Are results different for each design type? How can I choose the appropriate experimental design type?

    Jacques P. Beaugrand

    Asma:  Oui, c'est tout à fait possible. Techniquement, aucun problème.  Or, il y a des situations o\u l'un ou l'autre des modèles (inter vs intra)  peut s'appliquer (les postulats de base sont respectés)  et vous pouvez alors faire les deux types d'analyses et rapporter les résultats pour les deux. Je vais tenter de retrouver un exemple tiré de mes propres analyses (il y a 20 ans!).