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Dear all
Hope you are doing well!
What are the best books in Materials Science and Engineering (Basics and Advanced)? Moreover, what are the best skills (or materials topic related) that materials scientists have to develop and to acquire?
Thanks in advance
^_^
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Dear all, following a list of interesting books. My Regards
- Fundamentals of Materials Science and Engineering: An Integrated Approach, William D. Callister, David G. Rethwisch, 5th Edt (2015).
- Materials Science and Engineering: An Introduction, 10e WileyPLUS NextGen Card with Loose-Leaf Print Companion Set, Callister Jr., William D., Rethwisch, David G. 10th Edt (2018).
- The Science and Engineering of Materials, Donald R. Askeland, Wendelin J. Wright. 7th Edt (2014).
- Materials Science and Engineering: A First Course, V. Raghavan, (2004).
- Foundations of Materials Science and Engineering, Willaim Smith, Javed Hashemi, 6th Edt (2019).
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This may be a question that might not be an intelligent one, but still, this is how we learn tight.
Is it better to call CuFeO2 copper ferrite or delafossite? I know AB2O4 are called ferrites in general.
So in this case with the ABO2 structure, can we call this cuprous ferrite?
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Many chemicals have several names: trivial and systematic (IUPAC nomenclature, red book), and in this case there can be two nomenclature names - anionic and oxide form. In this case, delafossite is a trivial name (from mineralogy, but it can be from technology, everyday life ...), copper (I) ferrite is an anionic form (there is another copper ferrite CuFe2O4 - copper (II) ferrite) and copper oxide (I)-iron(III)) - oxide form of the systematic name.
... If names are not right, words do not fit. If words do not fit, affairs go wrong. ...A gentleman is nowise careless of his words. ... Confucius. Analects XII.3.
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metal carbide and nitride specly 4 5 6 group transition metal carbides and nitride.
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Visit kindly the following useful RG link:
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If metal sample of 10000 atoms have been irradiated using primary knock on atom(PKA) method and  and let 300 vacancies are generated and how can i show this number of vacancies in OVITO....
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I am interested in removing defects during metal LPBF like orientation adjustment, residual stresses, cracks, part failure, etc.
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For predictive simulation of these processes, we use Autodesk Netabb (https://www.autodesk.de/products/netfabb/features), which works great but is cost-intensive. We also use the Simulia Abaqus "AM Modeler" Plugin (https://info.simuleon.com/blog/using-abaqus-to-simulate-additive-manufacturing-printing-an-optimized-hip-implant) which costs less and also delivers good results for this process. These simulations might potentially help you to reduce the thermal and stress-induced defects and deformations in your parts. Further, it might support you to improve your support structure placement (if required for your process).
When considering micro-defects and the quality of the material after manufacturing, you should specify the type of defects that should be "removed". Maybe a simulation would not be appropriate and you should consider an In-Line process monitoring and control for your process, combined with a proper "Design of Experiments". The data achieved by this procedure could be used to improve the simulations mentioned above by considering your materials and machines constraints.
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Where can I find the publication "The theory of moving sources of heat and its application to metal treatments Trans"?
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This RG discussion (thread) is an open teaching & learning talk about the use of the TB method in the solid-state.
TB has proven to be a very powerful no-relativistic quantum mechanical (NRQM) technic in order to match experimental data and theories in several branches of solid-state where quasiparticle excitations play the fundamental role, i. e., electrons and holes in metals, magnons and phonons, and Cooper pairs among other systems, it helps even in the physics of insulated systems where there is a gap between the conduction and the valence bands.
TB helps to understand more deeply into solids with respect to the free & nearly free electron models. The 3 methods create a wonderful picture of quasiparticles and interactions that take place in solids. In addition, with visualizing tools, TB becomes a very powerful method that can lead to important conclusions and give physical insight into STP complicated problems.
I learned the subject using the IV chapter (electron in a perfect lattice) of the classical book by Prof. Rudolph Peierls “Quantum Theory of Solids”1955 [1]. Later on, the subject of TB was popularized by another couple of classical books: Prof. Ziman’s book “Principles of the Theory of Solids” – 1972 [2] & Profs. Ashcroft and Mermin´s book “Solid State Physics” [3] - 1976. Finally, the TB method was magistrally exposed by Prof. W. A. Harrison, "Electronic Structure and Properties of Solids" [4] - 1980.
TB implies that electrons & holes which are eigenstates of the Hamiltonian are spread entirely on the crystal (like in the free & nearly free eh-models), but that they also are localized at lattice sites (free & nearly free e-models do have no such a requirement). This is a really important statement. In addition, the TB approach for example helps to understand the metal insulation transition by means of the Peierls instability & transition between metallic and insulating solid states [4].
Nowadays, there are important advances, both theoretical such as the one where using a TB approach Prof. Chris Nelson [7] still has the only model that predicted the frustration-based behavior of the structural glass transition in As2Se3, He used TB to fit experimental nuclear quadrupole resonance data (NQR). In addition, with TB there are ab initio ones using this powerful, rigorous but also, intuitive tool in the physics of the solid-state, please see for the latest news on Green functions and TB [8].
All RG community members are welcome to discuss and share teaching and research findings using the TB method. Thank you all in advance for your participation.
Main References:
[1] Rudolph Peierls: Quantum theory of Solids. Clarendon Press, Oxford, 1955.
[2] J.M. Ziman: Principles of the Theory of Solids, Cambridge University Press, London, 1972.
[3] N.W. Ashcroft and N.D. Mermin: Solid State Physics, HRW International Editions, 1976.
[5] W. A. Harrison, Electronic Structure and Properties of Solids, Dover, New York, 1980.
[6] Rudolph Peierls: More Surprises in Theoretical Physics. Vol. 105. Princeton University Press, 1991.
[7] W. A. Harrison
[8] Chris Nelson, A frustration based model of the structural glass transition in As2Se3 201 Journal of Non-Crystalline Solids s 398–399:48–56
[9] S. Repetsky, I. Vyshyvana, S. Kruchinin, and S. Bellucci. 2020. Tight-binding model in the theory of disordered crystals. Modern Physics Letters B Vol. 34, No. 19
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Thank you so much for your post, Prof. Hadi Jabbar Alagealy
Very interesting to know that TB helps in the study & understanding of electron transfer in solid-state devices.
Best Regards.
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Dear and Distinguished Fellows from the solid-state physics RG community.
Does have anyone read after 20 years the preprint from Prof. Laughlin A Critique of two metals?
I read it when I was a PhD student. I think his opinion after 20 years deserves more attention. Please, feel free to follow down the link to the arXiv preprint if somebody has an interest and please leave your opinion:
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With the increasing demand, the consumption of metallic materials is increasing. But the primary sources of these materials (ores) are limited. So, there is an urgent need for an efficient recycling technique to meet the increasing demand. There are mainly two techniques, powder metallurgy and casting, used for recycling metallic materials. Which is the better technique, powder metallurgy or casting?
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Just came across this question. Slightly unrelated but aligned to re-cycling in the foundry environment.
Please see my paper on recycling waste foundry sand:
The paper also looks at alternative methods of recycling waste foundry sand.
Hope this might be of some use to your overall topic.
Best Regards
Martin
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In the (electro-) conducting materials, as I know, there is an energy gap between the valence band (VB) and the conduction band (CB) that can be brought to or near-to the Fermi level by doping (p-type or n-type dopant).
But ( My question is ), If I want to design a (semi- or super-) conductor's materials (inorganic or polymeric) , Which properties would I look for? and, also, Which characterizations would I consider for the properties' investigations? What are the requirements for the materials' property (with regard to its band structure) to achieve the considered structure-property relationships (or requirements ) for the preparation of the conducting materials?
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Indeed Dear Ahmed MS Dawelbeit it is a very interesting and subtle question, refer to it as a localization phenomenon is one way since electrons can be seen as wave packets that can be or not well defined within the structure (metal, either metallic polimer).
In general, we have a kinetic criterium with three well-defined regions, the product "l . kF", since we understand localization as the absence of diffusion of any kind of waves in a disordered medium.
Please check for the case of metallic polymers, the following reference:
Alan J. Heeger, 2003, The Critical Regime of the Metal-Insulator Transition in Conducting Polymers: Experimental Studies. Condensation and Coherence in Condensed Matter, pp. 30-35
it is very instructive
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I need to simulate the laser path with different patterns for metal additive manufacturing along with deposition of materials in ANSYS. Is there a way to do it?
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For simulating laser path in Ansys Workbench, download 'Moving Heat Source' extension from the Ansys store.
This video will be helpful:
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What is the mechanism and method of making the steel fibers used in reinforcing concrete and what are the residues or wastes or losses caused from the manufacturing stage ?
Are there detailed industry instructions that can be obtained ?
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Dear Ahmed Mousa,
Steel fibers are short discontinues strips of specially manufactured steel. Generally, their inclusion in the concrete improves the mechanical properties of concrete significantly. As the most common matrix, which is now mostly use in construction industry is Reinforced Cement Concrete. Main Reinforcement purpose is to resist bending due to applied load.
Ashish
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Dear academics and science enthusiasts,
I spent some free time trying to understand about the use of materials for liquid hydrogen storage. There is a big hype about hydrogen these days.
A lot of publications are out there for decades. Loads of papers and documents focusing on hydrogen tanks for space applications (but also auto and aero sector). Even though space engineering is not my field of expertise. Still the fundamentals are the same. The tanks need to be strong, tolerant, thermally stable and light weight. Reading around available materials that have been used already. I found the followings: stainless steels, Al-Li alloys, 2xxx series alloys, 7xxx series alloys, sandwich of multi-materials, Fe-Ni based, Ti-6-4, other titanium alloys, CFRPs...
It is nearly impossible to understand a material trend. And it's also difficult to understand which properties would govern material selection. Does this also show lack of knowledge/expertise? Ashby's plots have been out for decades. Alloy choice should have been a back of the envelope exercise.
What ideal alloys could be used for liquid hydrogen storage and why? I'm mostly curious to see different viewpoints rather than trying to seek the right answer.
Cheers,
Panos
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As you know, hydrogen has good prospects of becoming fuel number one in this World but science & technology have to solve some problems before the switch to hydrogen economy. One problem is finding a "cheap" process for producing H2 from H2O " water". Another problem is how to store H2 adequately since this gas escapes from the best of containers "in terms of materials & designs" and if there is leakage of pressurized H2 into the air , then a disaster will occur similar to what happened to Space Shuttle Challenger in 1986.
A third problem is the inherent behavior of H2 in having "annoying" explosive combustion "reaction with oxygen".
The second & third problems are related. If there is success in the interior design of light-weight containers or storage tanks so that H2 cannot run away, then there will be avoidance of material loss plus a disastrous outflow of the gas.
To store H2 in liquefied state, 2 items of equipment are needed (a compressor & a cooler) and these must give a temperature little below -252.87 °C and more than -259.14 °C for sufficient time. Liquefaction of H2 is cost-intensive & is undesired in practical usage.
Some brainy researchers thought of using metal alloys to store gaseous H2 (just like using a sponge to hold water) & these alloys, which sandwich the gas, are required to release it slowly. There is some progress in this research but I am not aware of a major "breakthrough".
Finally, some bright researches thought of storing H2 inside hydrides such as lithium aluminum hydride LiAlH) or sodium borohydride (NaBH4)or others with finding out ways of slow release of H2 gas that will proceed with smooth mild burning upon its use as a fuel.
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Hello,
I have been looking for a citable reference for this, but I'm not finding any.
So far I have found two links on the internet, which mention different values for it. One mentioned 17e28 1/m^3 and the other one, 8.5e28 1/m^3 (links provided below), and both seem to be blogs, so not citable.
Does anyone know which one is correct? Also, it would be really helpful if you could provide a citable reference for it.
Thank you.
1.
2.
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Dear Anouar Jbeli,
I agree with you. The free election density differs in bulk and surface and also on the lattice structure of Fe.
The election density of α-iron and β- iron are different obviously.
Thanks
N Das
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I am doing some leaching experiments now on metal-bearing wastes using citric acid as lixiviant. The metals of interest are REE, Co, Mo and V. Is there any specific method for each of them to be precipitated from organic (citrate) PLS? Or are the standard methods (e.g. precipitation of V using ammonia solutions) suitable for organic PLS?
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About predicting the pH of citric acid ― sodium citrate solutions and buffers for approx. pH < 4.0 ― cf. my post at:
About predicting the pH of citric acid ― sodium citrate solutions and buffers for approx. 4.0 < pH < 5.5 ― cf. my posts at: https://www.researchgate.net/post/Why-the-pH-of-Citrate-buffer-increases-when-diluted-with-water
About predicting the pH of citric acid ― sodium citrate solutions and buffers for approx. 5.5 < pH < 8.0 ― cf. my posts at: https://www.researchgate.net/post/Why-the-pH-of-Citrate-buffer-increases-when-diluted-with-water
About predicting the pH of citric acid ― sodium citrate solutions and buffers for approx. pH > 8.0 ― and for approx. pH > 9.0 ― cf. my posts at: https://www.researchgate.net/post/Why-the-pH-of-Citrate-buffer-increases-when-diluted-with-water
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Including the so-called kinematic hardening in phenomenological material models allows capturing the accumulation of plastic deformation in materials subjected to cyclic loadings. It determines that the size of the "elastic domain" in the deviatoric stress space remains constant and that upon plastic yielding, the domain is simply translated.
In largely deformed materials in tension, the kinematic hardening may result in a translation of the elastic domain to levels where the initial compression yield-limit becomes now a tensile stress value. This implies that upon unloading a plastically-deformed material (returning to zero loads), it may experience plastic deformation as well. My question is, is that physically possible? If yes, how can it be explained?
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Hi!
Kinematic hardening is only a simplified model that is convenient for describing the Bauschinger effect. More realistic is the combined model that combines isotropic and kinematic hardening.
V.N.
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Dear Fellows I checked very recent literature for the P-T phase diagram by means of exp. measurements on Metallic Hydrogen.
I found several interesting papers that show its metallic phase at high pressure: Any comments please? are there any new DFT calculations for a Metallic Hydrogen P-T Phase Diagram?
1. Metallic hydrogen F Silvera et al 2018 J. Phys.: Condens. Matter in press https://doi.org/10.1088/1361-648X/aac401
Figures 6 and 8
2. Insulator-metal transition in liquid hydrogen and deuterium
Shuqing Jiang, Nicholas Holtgrewe, Zachary M. Geballe, Sergey S. Lobanov, Mohammad F. Mahmood, R. Stewart McWilliams, Alexander F. Goncharov arXiv:1810.01360v1
Fig. 5
3. Theory of high pressure hydrogen, made simple Ioan B Magd˘au, Floris Balm and Graeme J Ackland
IOP Conf. Series: Journal of Physics: Conf. Series 950 (2017) 042059 doi :10.1088/1742-6596/950/4/042059
Fig. 1
4. Observation of the Wigner-Huntington transition to metallic hydrogen Ranga P. Dias, Isaac F. Silvera
Science  17 Feb 2017: Vol. 355, Issue 6326, pp. 715-718 DOI: 10.1126/science.aal1579
Fig 1
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The following publication deserves special attention in this thread:
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I'm wondering if some of you are aware of existing conversion factors for levels of metallic contamination in fish muscle tissues. In the present work, I'm focusing on metallic contamination, so not currently interested in lipid content of the tissues.
Depending of the contexts, concentrations are expressed relatively to fresh or dry weight. By example, working on muscle sample is more convenient when dried, but concentrations are expressed relatively to wet weigh in European directives, requiring conversion factors.
In most of the paper I read, concentrations are expressed relatively to wet or dry weight, and are then converted using a 5 times conversion ratio. But no information about the actual measurement of the ratio is provided, and I feel this value is largely empirical.
So, is someone aware of the rationale for this value ? Are you aware of papers specifically investigating this point ?
Thanks
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Pierre Cresson , great paper, I downloaded it early today and then came looking for more info on the conversion subject, and found the author himself :D Thank you!
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In our experiment, some metal surfaces are exposed to radiation heat under high vapor gas pressure.
I would like to ask if there is any way to calculate the boiling point for metals under high vapor pressure up to 1000 atm. Is it possible to use Clausius-Clapeyron relation? Is there any other formula? How to calculate the boiling point in such cases?
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You might look at the work of Friedrich Hensel. The Clausius–Clapeyron equation is valid, in principle, but the enthalpy of evaporation changes when the vapour phase undergoes the nonmetal/metal transition.
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1. What is the difference between hydrostatic and quasi-hydrostatic pressure?
2. Are all SPD techniques providing this pressure?
As Zhilayev et al. mentioned, Multi-directional forging (MDF) not providing quasi-hydrostatic condition in www.scientific.net/DDF.385.302
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Kiarash Mashoufi, thanks, your answer helped me anyway and I found the meaning of Mr zhilyaev comment by myself!
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In an alloy containing two different elements different in diffusion coefficient.
At high temperature, they diffuse or oscillate at different rates. Due to different oscillation rates, solute atoms possess compression force on neighboring solvent atoms.
May anyone give me a brief about this force?
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up
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Suppose metal conc are in range from 100 ppm to 500 ppm. the remaining conc are 30, 70, 90, 123, 245 etc at eq tym (80min)
v=25ml
m= 1g
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A complete guidance ..
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Hi all,
sorry for double-posting, but the "discussion topic" doesn't seem to get enough attention. We have recently started to work with Al single crystals for surface science experiments. Unfortunately, after a few cleaning cycles the crystal surface gets cloudy or "milky". Our typical cleaning cycle involves 1 kV Ar sputtering (ion current around 3-5 uA) x 30-60 min followed by annealing to 600-700 K (time varies, but typically not less than 15 min with somewhat fast ramping up and down, but no quenching). A high resolution XPS does not show any considerable amount of adsorbates or anything unusual whatsoever (some traces of oxygen which were there even for the mirror-like surface, some traces of carbon). Therefore, I suspect the crystal experienced some faceting/graining of the surface which resulted in that the surface has become mesoscopically rough. LEED spots have possibly become somewhat broader but this is really hard to estimate. Unfortunately, we had no time to perform AFM measurements on this surface. But it looks indeed as an annealing protocol is vitally important to keep the surface nice and well-defined. Therefore, I wonder if anyone else has experienced the same problem with Al (or maybe other crystals, too?) and/or knows how to overcome this issue? Maybe someone could share an annealing protocol or give a link to such a protocol if published? Tips and tricks? All meaningful opinions are welcome!
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Dear Nikolay A Vinogradov I'm not an expert in this field. However, I thought that the attached article could perhaps give you some useful information. It is entitled "Adsorption of oxygen on clean single crystal faces of aluminium" and was published in Surf. Sci. 1977, 62, 183-196. In this study it was found that thin islands of Al2O3-like oxide can form on the (100) face af the single-crystals.
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i have a question regarding dielectric constant of gold,cobalt oxide (co3O4) and n-tpe silicon . i find only one publication on this issue showing dielectric function cobalt oxide(CoO) 12.9 and gold 6.9 at 25 degree centrigrade ..can any one suggest where I can consider this for my simulations ?
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Can +3 cations form tartrate complexes?
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I) About iron(III) tartrate; cf. e.g.:
II) About aluminium(III) tartarate; cf. e.g.:
III) About lanthanum(III) tartrate complexes; cf. e.g.:
IV) About indium(III) tartrate; cf. e.g.:
V) On cerium(III) and thulium(III) tartrate complexes; cf.:
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Dear colleagues,
Dear colleagues, how to perform calculations of optical properties to find the best agreement with experimental data. I'm interested in metallic alloys (conductors), i.e. simple solid solutions (FCC, BCC, HCP) and Frank-Kasper (TCP) phases. I have access to wien2k code and would like to use it for this task.
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I personally use the FPLMTO method, implemented in the Lmtart code (MINDLAB), and I obtained results in very good agreement with those of the experimental work
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The fulid inside the journal bearing should have minimum amount of thickness so that no metal to metal contact will exist.
Is there any references or books for this ?
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Refer Raimondo and Boyd chart for same, you can refer my publication
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Some researchers are writing about this technology and saying that it has problems with interference when the product is wet or is placed where we find metal structures, as warehouses.
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This system works on different frequencies like low-frequency LF (125 – 135 kHz), high-frequency HF (13.65 MHZ) and, Ultra-high frequency (868-928 MHz) according to the requirements and applications.
High-frequency tags work fairly well on objects made of metal and can work around goods with medium to high water content. Typically, HF RFID systems work in ranges of inches, but they can have a maximum read range of about three feet (1 meter).
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I want to coat monolayer of silica particles on W surface, but it is difficult to get mono-layer because of hydrophobic nature of surface. Tried Oxygen plasma treatment to get hydrophilic, but could not get ! Any suggestions/comments are welcome.
Thanks !
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I guess oxygen plasma would work. I am also looking for making tungsten hydrophilic. If it has not worked for you, i shall try along with oxygen plasma little bit of argon and let you know the result. I wish to coat Ba and Sr Carbonates on tungsten. I have prepared the solution by mixing the powders with water. Solution seems to be consistent. I am unable to coat this solution on tungsten wire. I heated the wire to more than 2000 degrees by passing current into that, then tried to coat the paste, did not work.
Did you try etching it by HF acid ? I am going to try this. If I get results I shall post it here.
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Dear Researchers;
I have reviewed the mechanisms which cause fatigue failure, including the Wood and the Newman mechanisms, but they are both based on the movement of dislocations and slip-planes. BUT, as I know, the fatigue failure occurs below the yield stress, which means no dislocation movement occurs. Am I wrong? if yes, what is the main reason for fatigue failure?
Imagine there is an ideal surface of a component, without any surface microcracks or so. will there be any fatigue failure in it? if so, how does it occur?
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Dear Ali:
Dr. Mandal is correct - this was the dilemma that faced the early engineers studying the first recognized fatigue failures in the mid 1800s - how could a component fail at stresses below the yield strength? The answer of course is local stress concentrations particularly at the surface, i.e., from microstructural defects, inclusions, pre-existing microcracks, notches - and often tensile residual stresses, all of which generate locally high stresses (exceeding the yield strength) to promote dislocation activity in the form of cyclic plasticity to initiate and grow fatigue cracks. Since stress is the most important factor promoting fatigue failures - the fatigue lifetime is invariably a function of the stress raised to a high power - lowering the far-field (applied) stresses has to be combined with considerations of design, e.g., by minimizing the presence of notches (the first commercial jet airlines, the De Havilland Comets in the 1950s, failed by fatigue cracks in the fuselage which initiated at the corners of the plane's square windows), reducing the presence of inclusions and other microstructural defects, smoothing the surface of the component to try and remove nicks, scratches, cracks, and ideally putting in beneficial compressive residual stresses - by such processes as shot-peening, laser-shocking, burnishing, cold rolling, etc. - and/or hardened surface layers - by the same types of procedures.
The notion of an ideal surface without imperfections is naturally purely hypothetical. However, if you can polish a surface together with imparting beneficial surface residual stresses, it is possible to suppress the initiation of fatigue cracks at the surface, which transitions the initiation process to occur from sub-surface cracks. As internal cracks have to be essentially twice as large to surface cracks to have the same effect (all other things being equal) and that the initial growth of such internal cracks will not be subjected to external environmental effects, i.e., they will initially grow in vacuo (these sub-surface initiated fatigue cracks are often referred to as "fisheyes"), the fatigue life of the component can be dramatically extended.
Just a final note, whereas metal fatigue is dominated by the role of dislocation plasticity, ceramics can also fatigue by an entirely different process which has nothing to do with dislocations. The effect is much smaller - more subtle may be a better description - but can occur in toughened ceramics and their composites by the cyclic loading induced degradation of their toughening mechanisms, specifically from crack-tip shielding by such mechanisms as crack bridging. If this is of interest, the attached article can provide further details.
ROR
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I express a recombinant protein in E. coli that requires Mg2+ and ATP to remove bound chaperones and activate the enzyme, but also requires TCEP. I currently achieve active protein, but with very low specific activity of which a large fraction exists as soluble aggregates.
We have always added all 3 of these reagents during lysis at the same time. I am wondering if this does not maximize their efficacy. The concentrations we use are 1 mM TCEP, 2 mM Mg2+, and 5 mM ATP. I know that metals can interfere with the action of TCEP, and TCEP may interfere with the action of Mg2+. Does anyone else have any experience working with these reagents together? Would it be more efficient to add these reagents step-wise, e.g. starting without Mg2+ and ATP to give the TCEP a chance to work alone and then adding the other reagents after like 10-15 minutes?
Any help you can provide will be appreciated. BTW, we use B-PER as our lysis buffer base and add these reagents to the BPER.
Thanks,
Nathan
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Be careful with TCEP.
It does have a mild cysteine directed side-reaction proteolytic activity that may be a problem in some cases.
Ref:
Title:
A Tris (2-Carboxyethyl) Phosphine (TCEP) Related Cleavage on Cysteine-Containing Proteins
Introduced in the late 1980s as a reducing reagent, Tris (2-carboxyethyl) phosphine (TCEP) has now become one of the most widely used protein reductants. To date, only a few studies on its side reactions have been published. We report the observation of a side reaction that cleaves protein backbones under mild conditions by fracturing the cysteine residues, thus generating heterogeneous peptides containing different moieties from the fractured cysteine. The peptide products were analyzed by high performance liquid chromatography and tandem mass spectrometry (LC/MS/MS). Peptides with a primary amine and a carboxylic acid as termini were observed, and others were found to contain amidated or formamidated carboxy termini, or formylated or glyoxylic amino termini. Formamidation of the carboxy terminus and the formation of glyoxylic amino terminus were unexpected reactions since both involve breaking of carbon–carbon bonds in cysteine.
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I have a question about DC and AC Conductivity for Metals Vs Dielectrics? It may be easier to explain what I understand, and have people correct me.
For Conducting Metals, DC conductivity is usually very high. As the frequency increases the combined DC and AC conductivity starts to decrease(following Drude model), and it does so like a low pass filter so that the total conductivity of the metal is decreasing with frequency (Due to free charge mobility, and skin effect?)
For Dielectrics, the story is reversed. DC conductivity is usually very low, as they are insulators. As the frequency increases the AC conductivity increases, increasing the total system conductivity and lowering overall resistance following the universal dielectric response model. The physics here may have to do with molecular/ionic resonances, so the increase with frequency is not linear, and has peaks corresponding to resonances.
Please correct me if/where I am wrong. Please also tell me if I am right:)
Thank you very much in advance.
Edit: Better phrasing, and added a few sentences.
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Your answer looks pretty neat, I only would suggest adding a few words about the skin effect for AC currents. Skin depth decreases AC conductivity in metals.
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Hello everyone,
Can anyone please suggest me a good textbook/source that discusses porosity and inclusions of metals or aluminium?
I am struggling to find one.
Appreciate your time
Mohammed
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Dear Fellow Researchers,
I need your guidance to clarify questions a Reviewer has on estimating Ci in our binary mixture toxicity study.
Our Derivation of Ci: 1) For binary mixture, we ran separate Probit analysis for the organism’s response against each metal concentrations (C1 and C2) in the binary mixture (C1+C2). 2) We took Ci as the concentration of each metal in mixture where 50% response occurred in the Probit analysis. Reviewer says we are wrong! Hence recommended that manuscript be rejected!
Reviewer’s Suggestion on Ci: 1) Calculate concentration of binary mixture (Cmix) for the two different metals as Cmix = pi.Ci (metal 1) + pi.Ci (metal 2) where pi is proportion of each metal in the mixture. 2) Determine LC50 for Cmix. 3) Calculate the concentration of each metal (Ci) in the LC50mix.
Questions: Is it possible to combine the concentration of two different metals as a single mixture concentration?
To my knowledge, to describe mixtures of unidentical metals, one states each metal concentrations in the mixture e.g. Say we mix 2.5 ug Cd/L with 4.5 ug As/L, then one can state the binary mixture as 2.5/4.5 ug/L Cd-As or Cd/As mixture equals 2.5/4.5 ug/L. Many articles we cited gave the individual metals in the mixture separately as well and not as a combined single mixture concentration.
Could you please help clarify how possible to give a single mixture concentration for different metals?
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Actually, I'm expecting answer to perform a computational program and its code related concept. 
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Hey!
I had a query along similar lines though I have been working with the Python meep wrapper for a while now, I keep facing a problem with metallic components say thin films of metal. The field intensity blows up near a metallic film and hence when you run a Meep code for something as simple as calculating the transmittance of the said film the code shows an error because of Inf field intensities.
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How is electron-phonon scattering treated in metals in the context of transport ? I believe that the conventional deformation potential theory used for semiconductors fails in case of metals due to the presence of multiple bands around Fermi level. Is a rigorous treatment using both electron and phonon bandstructure of metals the only way to do scattering in metals ? Or are there approximations that one can use (like deformation potential theory for semiconductors) ?
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Yes Dear Prof. Prasad Sarangapani
Electron-phonon interaction in normal metals leads to a sound attenuation effect in normal metals (by contrast to metals below the transition temperature which leads to a different calculation)
1. The classical work to study electron-phonon scattering in normal metals using physical kinetics (what you call transport) is:
Course Of Theoretical Physics Volume 10 Physical Kinetics
L. P. Pitaevskii & E.M. Lifshitz. Pergamon 1981. For normal metals see ch. IX- & 79. pp. 334.
2. The classical work about sound attenuation in normal metals is:
Theory of Ultrasonic Attenuation in Metals and Magneto-Acoustic Oscillations
Proc. R. Soc. Lond. A. B. Pippard, 1960.
(without & with magnetic field)
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I'll be making use of zinc solutions and as much as possible I don't want to cross-contaminate my samples
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hot solution 4% HNO3 is available
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Hello to all :
This question is originated from the idea that every material (except for Superconductors) has a Seebeck Coefficient (S) different than zero, and from the idea that in every case when different metals or semiconductor materials are joined together, a Seebeck Effect at any scale is observed on the pair of materials.
So my question is:
When we measure the S of a given material, we place the sample between two plates at different temperatures, so we can stablish a Temperature Gradient and an unidirectional Heat Flux across the material. Then, we vary the Thermal Power imput, so we can vary the Temperature Gradient and obtain a set of Output Seebeck Voltages.
Then, we measure this Output Voltage and we plot a Graph of Delta(T) vs. Delta(V) as a linear x vs. y Graph. Finally we state that the slope of this Graph (positive for the N-Type materials and negative for P-Type) (because what we are measuring in our apparatus is the net Gradient (DeltaV/DeltaT), the formula in the Seebeck Coefficient has and additional (-) sign which turns S to a negative for N-Type semiconductors and positive por P-Type) is the Seebeck Coeff. for the material.
This measurement is always considered as if it was the absolute S coefficient of the material. But, What about the junction between the probe electrodes and our sample ? Since there is a Seebeck Voltage being generated at the junction too. Hence, our lecture from the voltmeter should be the Seebeck Coefficient of the junction: Se,s = Se - Ss
Where:
Se,s : is the Seebeck Coefficient of the junction between the sample and the electrode.
Se : is the Seebeck Coefficient of the Electrode.
Ss : is the Seebeck Coefficient of the Sample.
What do you think ?
Is this error virtually zero in practice, as much as we can ignore the effect of the Seebeck Effect of the junction electrodes/sample ?
How can we understand the fact that when we use these methods, we never talk about the contribution of he probe electrodes into the measured S Coefficient ?
Kind Regards !
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Dear Thomas Anthony Troszak ,
if you use extensions of the same material and connect them under the same conditons, the additional thermovoltages rule out. But you must ever be sure, what you exactly do. Let me give an example used in practice:
Thermocouples are used in vacuum container to determine temperatures. Lets say, you want to bake out a recipient or you want to heat a sample holder to a certain temperature. You fix your thermocouple to the corresponding point the temperature T you want to control. It can be that the couple is not long enough. Furthermore, you have a feedthrough you must connect your wires with it. Then you have almost different metals. On the outside you must use a special plug which contains a contact of the identical material combination. The material combinations are standardized (example type K). The outer contact lies at room temperature. With a control unit which measures the T you control the heater. Of course, if you have more extensions, the contacts between different materials can be different (oxidation, lubrication). Therefore, it is important, if you want exact results, to control the measurement of T.
First test: The thermovoltage must be zero, if both contacts have the same T (room temperature). If there are any contact potentials then you see them.
Second test: You put your "hot contact" into a reference liquid (boiling point must be known). Then you must get the right temperature difference.
With Regards
R. Mitdank
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Dear all :
May anyone share with me a Graph showing the curves for Temperature vs Thermal Conductivity, and Temperature vs. Electrical Conductivity/Seebeck Coefficient (in the same Graph) for distinct type of materials: (semiconductors, semiconductor alloys, metals, semimetals, etc.) showing the points in the range up to 1000°C ?
This is for use in Thermoelectric materials.
If someone can send it to me I'll appreciate it a lot
Thanks !
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Dear Franklin,
You will get these graphs in many literature. But it is not possible to get these graphs upto 1000 degree celsius for all materials.
Anyway, I think it is better to get these results by your own Experiments because standard data always doesn't match with your working material due to impurities and difference in microstructures.
If anything you want regaring the Experimental details for these I can tell you ( but upto 600 degree Celsius)
Love and Regards
N Das
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How do I interprete B and Afor metal adsorption? I found B and AT value 1.05 and 49.08 respectively. please tell the importance of the above mentioned parameters in biosorption?
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Dear Loren,
Here is your answer for determination of physical or chemical sorption from Temkin isotherm.
From Temkin isotherm, you got the value of two constants i.e. Temkin isotherm equilibrium binding constant (L/g) (= A) and Constant related to heat of sorption (J/mol) (= B). After getting heat of sorption value, you have to convert it kcal/mol from J/mol. If heat of sorption value is less than 1.0 kcal/mol, then physical adsorption is occurs. And its value 20-50 kcal/mol, then chemical adsorption is occurs. If heat of sorption value is in-between (1 - 20 kcal/mol), than both physical and chemical adsorptions are involved in the adsorption.
I think this answer may be helpful to your research.
With Regards,
Dr. Himanshu Patel
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Hi everyone, does someone know the work principles that VASP(The Vienna Ab initio simulation package) calculate elastic constant? I have checked many literature and they applied a matrix to unit cell, but I don't know if they are used by current version VASP(5.3.3). When I check OUTCAR, I can only find the elastic constants, but I cannot find where is the process, i.e, the matrix applied and the energy of strained lattice. Can someone tell me how to find those data, or introduce some literature about this?
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Dear Yixian,
I have just developed a toolkit for elastic constant calculation using the stress-strain method combined with VASP.
ElasTool is an automated toolkit for calculating the second-order elastic constants (SOECs) of any crystal systems belonging to two- and three-dimensional. It can utilize three kinds of strain-matrix sets, the high-efficiency strain-matrix sets (OHESS), the universal linear-independent coupling strains (ULICS) [2] and the all single-element strain-matrix sets (ASESS) to calculate the SOECs automatically. In an automatic manner, ElasTool can deal with both zero- and high-temperature elastic constants.
Best,
Zhongli
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I have to do few toxicity tests in which silver is involved. To do that i have to prepare a stock solution using silver nitrate (AgNO3) salt. The concentration of exposure in the tests is referred to silver itself, not to the compound. I need to know how much silver nitrate salt i need to have the concentration of 5 g/L of Ag. I would be really glad if someone could also explain/show the mathematical and logical reasoning behind the answer.
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You're welcome. I just noted a typing error in my answer. 0.786 g AgNO3 is of course 4.63 mmole, not 6.63 mmole. It must be the same as the mmole amount of Ag.
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What are the causes and mechanisms of plastic deformation of ceramics, polymers, composites acros macro, micro and nano scales? how theses mechanisms can be compared with metal? please provide links for research articles and textbooks that introduce deformation of all four kinds of materials simultaneously
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Plastics can show two types of deformations, ductile or brittle. Thermoset plastic will show brittle failure because of the high crosslinking density of the log and stiff polymeric chain, hyperbranched structures and what not while the thermoplastics show elongation as in their strain is high under stress. The length and area of the thermoplastic are bound to change. While ceramics are exclusively brittle, hence, after a very to very low elastic response, the ceramics rupture without showing any form of deformation. As in the shape of ceramics do not change rather they undergo fracture soon after a small elastic region. The above analogy is for monolithic materials without any secondary dispersed phase. Composites, on the other hand, are multiphase materials and hence, their deformation is dependent largely on the reinforcement. A fiber-reinforced composite offers multi-step deformation, in this case, matrix fails first followed by fiber failure which is not a catastrophic failure rather than the fiber failure occurs in steps giving you a fine warning about the future failure. Composites always give you warning before they fail and hence, their deformation is largely categorized as brittle or ductile along with fiber pullout, and fiber bridging. If the fiber-matrix bonding is too strong expect a single step failure without any deformation or change in shape or size, while in case of weak fiber-matrix bonding, the fiber pullout a fiber bridging offer a bit of reformation and high toughness which is categorized as a ductile fracture. Matrix also plays an important role. Composite can't be generalized, you can design and modify the properties as per your needs. Hence, not all composite show same deformation or mechanical, thermal, physical response.
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I have ploted 1/A-Ao versues 1/[M]1/3. But I am getting negative intercept in Benesi Hildebrand plot for Ligand and metal in 3:1 ratio
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Liu Wei did we calculated normally? Or there is another aproach?
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Octo-Alloy, also called Ashtadhatu, is a traditional alloy to produce religious idols, ornaments and sculptures in indian subcontinent. My question regarding the alloy is
  • According to wikipedia,( https://en.wikipedia.org/wiki/ Ashtadhatu ), the alloy consists of gold, silver, copper, lead, zinc, tin, iron and antimony or mercury . Does this alloy consisting of so many dissimilar metals undergo phase separation during casting? Are there any research papers available about microstructure of this alloy, or about phase separation prevention of this alloy?
  • Again, some ornaments, especially bangles made of this alloy are made in forms of two interwinning wires of different color. Which metals are incorporated into which wire?
  • Where can I get credible Archeometallurgical and contemporary methods of casting (temperature, composition, time)and metalworking ( embossing, scribing) of this alloy? Was this work of a jeweler, a sculptor or a metallurgist?
  • Is there any possibility that the alloy is a high-entropy alloy? Have there been any research on molecular dynamics simulation of high entropy alloy of these particular alloying elements? I have not found any in interatomic potential repository
  • Had there been any research on MEDICAL (NOT ASTROLOGICAL) benefit of using octo-alloy( more specifically its self-disinfecting capability and heavy metal poisoning hazard)?
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You have raised a very attractive querry.You may get clarification and understanding on some points raised in your querry by approaching prof b s murty, director iit hyderabad. He has a book on high entropy alloys and is an ex-student of eminent metallurgist&material scientist Prof.S Ranganathan of iisc bangalore.
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I have read that to know the composition of different phases in a ternary phase diagram of metals A,B,C (at a particular temp. T), we can apply lever rule along the tie line. But, I am not sure about how to draw the tie line and how to apply lever rule along it as some procedure says to use line and few have mentioned smaller triangles to draw (tie-triangles) to know the composition of the phases. Kindly illustrate on the concept. Thanks in advance for help.
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Dear Adhidesh,
Unfortunately, you can not predict those tie lines that you see in ternary phase diagrams, they are experimentally determined by different techniques depending on what kind of sample you have (NMR spectroscopy, low-angle x-ray scattering and etc...). Usually, when the two phases region is determined, the tie lines are determined as well. I think your question was: can i draw the tie limes (by geometry or any other mathematical means) if i know the limits of the two phases region? The answer is no, those lines are experimentally determined by analyzing the composition of the two phases.
For example, if you know the limits of the two phases, what you do is take many samples inside the two phases region and determine analytically the composition of each phase: if you have one phase with 25% of A, 50% of B and 25% of C and the other phase with 60% of A, 30% of B and 10% of C, you now have two points that can be connected to form one tie line.
Once you have sufficiently tie lines inside your two phases region, other tie lines can be predicted (conjugate lines).
Best,
Thiago.
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Hello everyone,
I would like to know if someone have a reference or a possible explanation about if ketones (2-propanone or ethyl acetate) could coordinate to iron (metal or cation)?
Since ketones present two pair of free electron availables, I suppose that could coordinate to iron because this metal present a free d-orbital.
Nevertheless, I did not found an article or research about this.
Could some one help me?
Kind regards,
Julián.
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Hi. How about 1,3-diketone ?
Such as -----> Tris(acetylacetonato) iron(III)
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see above
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Erkan Yersel I also would like to know that!
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Are there any standard procedures or scientific price list to evaluate the cost of the materials (for industrial mass production)? I want to compare the price of alloys based on its elemental content. I know that the metal costs fluctuate but any scientific procedure to evaluate the alloy cost?
Thanks.
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Usually, what a customer is willing to pay for an alloy is determined by its properties, not its chemistry. That is, one may assume that customers buy the cheapest alloy that meets their needs. Of course, properties are determined by the specific combination of chemisty, processing, and microstructure. For example, most Al alloys are over 90% Al; and therefore, on a commodity basis they should all cost about the same. However, the processing and heat treatments required to get the properties required for aircraft alloys has a strong influence on their final price. However, let us suppose one only wants to look at the cost of the elemental constituents for some analysis. What level of purity should one use for each element in this calculation? That is, the cost of an element in "pure form" can vary greatly with the degree of purity. An element can be very inexpensive at a commercial purity of 99.8%, but orders of magnitude more expensive at 99.9998%. The 0.2% could be elements that ruin the properties of a high tech alloy, but are perfectly acceptable in a low tech alloy. These requirements will be a significant factor in determining the price of the commodities required to make an alloy.
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We need an artefact-free preparation of AA2024-T3 for EBSD investigations? Does anybody have recommendations?
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Hi we routinely do EBSD of Aerospace Alloys and our final mechanical polish is with a soft silk cloth using 0.25micron. We then always ion beam mill usually at 8kV for 15min at 4degrees followed by 2kV at 5degrees for another 8min. Finally 400V at 5degrees for 5minutes. This consistently produces good results on the bulk Al and intermetallics.
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I'm interested to know how long it takes for the oxide layer to reform after it has been broken. Is it on the order of nanoseconds, faster, slower?
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Thank you for the references sir!
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Metals & Mining is an important industry for both developing and developed countries. The aim of the question is to find what new trends and technological modifications are happening in this industry which may have any disruptive impact on the whole industry from the point of view of energy sector. Like there could be new ways mining is done or any new ways an ore can be extracted which consumes less power or is more sustainable. Or are there any specific ores which consumes lot of energy and which needs improvements in overall technology.
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Dear followers, I'm actively working on different ways to valorize biomass in biobased economy : bioenergy is not the first way of valorization which could be favoured (Lansink valorization). What can we do with Salix species which have grown on polluted soils ? If metals are capted by plantes, can we extract metals ? or other high value molecules ? Which plants do industries need ? or you as researchers ?
Do you need biomass ? Which one ? How many ?
Please.. give me some informations about that.
Aricia a.evlard@valbiom.be - follow my projet for Wallonia.
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My question is related to density measurement by Archimedes principle.
1. Does the amount of liquid in which the density of metal piece is being measured also matters?
2. Does the size of container affects the measured density?
3. Does this method give accurate density calculation for metal piece with weight above 1kg?
4. What should be the ideal position of metal object in water? Either it should be close to the surface or close to the bottom of container?
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Hi Afza,
there are just two things you hve to be aware of the liquid should wet the sample and should not react with it. It should not evaporate quickly. The sample has to be completely immersed how deep the sample is in the liquid does not matter. You should control the temperature of the liquid (accuracy +/- 0.1 °C to have the correct density, for water you can find reliable density data.
We measure ceramics with an accuracy of 0.001 g/cm² if samples have a weight of ~ 10g. The bigger the sample the better the accuracy.
best regards
Frank
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I am interested in Bioleaching method. 
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It is dependent to Fe and Ti phases. If these elements are in sulfide or oxide form, the most simple way to remove iron is using Iron and Sulfur oxidizing micro-organisms such as acidithiobacillus ferrooxidans and acidithiobacillus thiooxidans. These microorganisms produce sulfuric acid and dissolve the Fe by providing an oxidizing environment.
However, if Fe and Ti are in silicate phase using fungi (Such as aspergillus niger) can be better. These microorganisms decompose the silicate structures by producing organic acids which results to Fe dissolution.
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sheet metal, fiber metal laminate or sandwich structure forming
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as per standards u can take 2.5 mm radius of circle. However you have to take ratio of original dimension and final dimension of circle, you can go for 5 mm radius of circle as well. This will not affect ur results.
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i want to know which elements (specially metals) have enrichment in brines and/or oilfield brines and what origin of them.
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Metal cations like Na, K, Ca, Mg and Li (some 1000 to 10 mg/kg) can be found in dependance of geochemical composition. Their origin is from salts (e.g. Muschelkalk in the Molasse basin).
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Im trying to find out if it would be possible to create a stencil from a metal plate by removing a thin strip of material all the way through. The groove would need dimensions of : 100nm wide and about 500 micrometres deep. The length doesn't really matter. Im trying to think of ways to grow nanowires using a metal stencil instead of growing onto a layer of resist and removing via liftoff. Iv heard that FIB can reach the resolution I need but not sure if it could reach the depths im looking for.
Any suggestions? Thankyou
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I second Dimitar's answer And add that you more than likely will need a femtosecond laser specifically. With longer pulse width, especially close to nanosecond, you might end up having melt zones near your machined edges. These melt edges may be in the form of microscopic bumps. I would try to avoid such artifacts for a nanostencil application.
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I'm intersted by the eliashberg spectral function which represent an important information about the contribution of the frequencies of phonons on the creation of the electron-phonon coupling strenght .
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Thanks Dear Prof.
Behnam Farid
yes, my mistake, I confused the statistical operator \hat{\rho}={{e}^(\beta(\Omega -\hat(H}+ \mu \hat(N)) with the thermodynamical potential \Omega used in statistical physics, and as you stated is not an operator, but a real number, deduced from the Helmholtz free energy . \Omega does not have a hat, inside the statistical operator \hat{\rho}. The potential \Omega_o can be calculated as the trace of the operators (\hat(H}_o - \mu \hat(N)) for the case of quantum statistics. But still, I read from the previous answers, that the Fermi energy is a fundamental scale and the Debay frecuency play an important rol as the cut-off frequency? Thanks Dear Prof Baldomir and Dear Ilias Serifi as well.
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Dear colleagues,
Would any of you guide me to literature papers or websites which compiled the temperature dependent (T>1000K) oxidation rates of various materials (metals, ceramiques, plastics, etc)?
Thank you very much for your attention.
Best regards.
Adrien.
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You can read Callister reference "Materials Science and Engineering
An Introduction"
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I am trying to synthesize hydroxy acetyl coumarin schiff base complexes via different metals. common reported procedures for complex synthesizing did not result in any conclusion. any suggestions???
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It is known that bulk materials and thin films represent two different universes in terms of diffusion controlled transformations. Are commonly used phase diagrams, mainly made using bulk materials investigations, can find application in the exploration of thin films?
Dear colleagues, what is your opinion on this topic?
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By processes implying low temperature (i.e. Pvd or electrodeposotion) you can obtain alloys not predicted by phase diagrams (that are constructed for equilibrium conditions). These alloys are not thermodynamically stable. So if you increase the temperature, they can decrease their excess of energy and you obtain a thin film exactly composed of the phases predicted by the phase diagram of the bulk material. It happens at ambiant temperature with thin film of gold deposited on copper. With ageing, the copper and gold diffuse and at the end your (cheap) watch becomes pink.
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As you know, for High SFE materials, cDRX is the possible mechanism for convert Low angle grain boundaries (LAGB) to High angle grain boundaries (HAGB) during strengthening. But generally cDRX happen at high temperatures and instead of that, fragmentation mechanism is suggested. what are the intrinsic features of both of them and how can we distinguish cDRX from fragmentation?
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Dear Ali,
As you know, we say CDRX because there is not distinct steps of nucleation and growth. During CDRX, whole of the microstructural evolution is continuous. So, it can be occurred by transformation of LAGBs to HAGBs, fragmentation, GDRX, etc. You can consider the GDRX and fragmentation mechanism as some types of CDRX. The term "fragmentation" some times has been used instead of CDRX in literature.
Please note that in most cases it is very hard to distinguish the different restoration mechanisms. For example, it is well developed that CDRX does not inherit the deformation texture. However, I found in my research that the existence of deformation textures in the material can not always be the sign of CDRX.
I think the story of dynamic restoration mechanisms have not been completed, yet.
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Is it possible to obtaining a modelization of metals, pesticides and other pollutants in surface water along time and space in a watershed? Many softwares, predicts flows, O2, carbon, nitrogen, etc., such as SWAT and Basins but.. what about pollutants?
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It is not possible to model all three classes together. The all have different chemical properties (adsorption, photolysis, concentration range) and you will have serious problems to get data for validation. In addition you will also have to take care of sediment/water/plant interactions. Check out your data set, lab facilities and then focus on a few substances.
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Hello Everyone,
I am working on the SAR data analysis for the geological domain. I had used SAR for the geological features extraction. But now I am going to use SAR data for mineral mapping. Could anyone help me regarding the mineral identification using SAR?
Thanks
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Hi Ronak, there is an interesting article for you. It is accessible online: Atzori S, Salvi S (2014) SAR Data Analysis in Solid Earth Geophysics: From Science to Risk Management, DOI: 10.5772/57479
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Hi
how do we prevent to produce by-products like niroso  or N-hydroxy aromatic compounds and etc, in reduction of nitro aromatic compounds by hydrazinehydrate in  presence of heterogeneous metallic catalyst?
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By reduction of Nitro group in aromatic compound to amine group by using
H2/ Pd or Ni as a catalyst .
Regards
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differences between macro-structure and micro-structure in commercial pure aluminum
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Hi! I am interested in cases of anomaliously low Young's modulus in metall matrix composites probed by compressive/tensile tests. Do you have any interesting ones to share?
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Hi Sergio, thanks for the question! By anomalously low, I mean the case when the Young's modulus value of a composite is about 2 or more times lower as compared with the modulus value of its component exhibiting the lowest modulus value.
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I am in search for articles that address metal scarcity and how it could potentially affect the energy transition. I have found good studies on copper but not many on other metals. Suggestions?
Thank you.
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You are welcome Julia Lucchese
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Simulating (Lumerical solutions) a gold nanoparticle (NP) on a gold film structure. For NP in free space, we confirm the simulations results with Mie theory. How about in case of NP on a film structure. And another case with be a dielectric layer in between Np and metal film. How we can confirm the simulation results are correct?
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As far as I know there is no analytical solution for this problem (but I might be wrong). In such cases I would use two different Maxwell-solver for example an FDTD-based like FDTD solutions and a second one like a finite-element-based like the one that is used in COMSOL. If both solutions converge for decreasing mesh sizes you can consider yourself to be fairly safe. On a second thought, how about carrying out the corresponding experiment?... ;-)
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Hello,
Here is the chemical mobility for a Fe-Cr binary alloy given by Darken's equation (Refer - Effect of applied strain on phase separation of Fe–28 at.% Cr alloy: 3D phase-field simulation):
M = (Ccr*Mfe + Cfe*Mcr)*Ccr*Cfe/Vm
1. How did the terms (Ccr*Cfe/Vm) arrive in this equation, since the inter-diffusion coefficient is just given by D = Ccr*Dfe + Cfe*Dcr?
2. What is the unit for mobility? For a mono-Vacancy mechanism, the diffusion coefficient is given by D=R*T*M. If the diffusion coefficient is given by m2/s , then can I just assume the corresponding mobility also has units in terms of m2?
It would be great if you provide any fundamental text books for understanding this.
Thank you.
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The connection between diffusivity and mobility M=D/kT is known as The Einstein- Nern
st equation in the absence of the chemical factor, which may be easily derived from the drift-diffusion equation in the presence of the additional driving force, which is a gradient of the applied external field at the steady state considerations,only!!!.
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 Mining is  water intensive and is estimated to generate hundreds of millions of tonnes of wastewater each year. Mining industries are under  pressure to contain, control and clear up mine waste water from their  process. Precious metal recovery  such as gold, copper and  highly valuable metals can be recovered.
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Kindly read this article
Xionghui Ji Saihua LiuHuang Juan John Jiang Ailan HeElena Bocharnikova Vladimir Matichenkov
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Our research group is working on a rather large pair of manuscripts summarizing geochemistry from 12 sediment cores from all 5 of the Laurentian Great Lakes. MS1 is a literature summary of metals and oxides that are found in the sediments, and their likely sources. MS2 is the paleo paper, reconstructing ~300 years of geochemical indicators in each lake.
Both manuscripts are much larger than is typically accepted in a journal like the Journal of Great Lakes Research. I'm sure we can ask for exceptions, but figured I would ask if others have ideas about appropriate venues for such a pair of papers. They aren't quite large enough to make a special issue on their own. We have also considered two big chapters in a book, but again I'm not sure of the best venue for such a thing and whether it is a complicated process.
Any input is appreciated!
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How about Frontiers -they published Review with max. length 12'000 words and 15 Figures and/or tables .
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The mixture release  to electrolyte when the GCE is immerged to the electrolyte.
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Thanks a lot for your answer
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Metals have their negative permittivity at optical frequencies. 
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