Science topics: Chemistry
Science topic

Chemistry - Science topic

Chemistry is the science of matter, especially its chemical reactions, but also its composition, structure and properties. Chemistry is concerned with atoms and their interactions with other atoms, and particularly with the properties of chemical bonds.
Questions related to Chemistry
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Hello everyone! I'm investigating/evaluating some new etch chemistries to etch and polish Indium Antimonide wafers after a mechanical grind operation. Due to ventilation and other concerns, my lab is unwilling to bring Br2 or Acetic, or Lactic acid in as polishing etch components. I'm having trouble finding chemistries that both etch fast enough to be viable (1.0-1.5um/min) and fully remove grind marks/polish wafer. I would prefer one fast etch that leaves a polished surface after 20-40um.
Failing that, I need to at least find a good polishing etch.
Thank you for reading!
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Cf. H. Simchi, Sh. Bahreani, M.H. Saani, "Cleaning InSb wafers for manufacturing InSb detectors", Eur. Phys. J. Appl. Phys., 33, 2006, pp. 1-4.
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I have seen in the book of mechanism and theory in organic chemistry (1977, Lowrey, et al) that (Me)3P is stronger nucleophile than (MeO)3P. Table 4.5, page 188. But what about alpha effect? I think that because of alpha effect, trimethoxyphosphine should be stronger nucleophile.
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Dear Mohammad Javaherian many thanks for the interesting technical question. It's interesting to see that there are already some rather differing answers. I agree with Sebastian Jung in that the "alpha effect" does not play any important role here. I don't see a mesomeric effect of the methyl groups either because the phosphorus atom has a free electron pair and not a positive charge. Instead, the electron-withdrawing oxygens in trimethylphosphite will lead to the effect that the free electron pair at phosphorus has more s-character, making P(OMe)3 a weaker nucleophile. In contrast, the free electron pair at the P atom in trimethylphosphine has more p-character so that PMe3 is the stronger nucleophile and a better donor ligand toward transition metals. For some very useful overview on the different properties of various ligands please have a look at the following article:
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when I wash the cells that emit fluorescent by PBS for flowcytometry, emittion of rhodamine b is very low
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I am not sure if rhodamine b are sensitive to substances like washing, buffer or even PBS. Make sure the fluorophore is hold tight on the sample.
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I am developing a tablet of bcs class 2 molecule. I used here Magnesium stearate, microcrystalline cellulose, povidone K-30, sodium starch glycolate. Coating: Hypromellose, iron oxide black, PEG 400), polysorbate 80, titanium dioxide.
Dissolution media -50 mM Sodium Acetate buffer, pH 4.5, containing 0.75% SDS.
The problem is that when i conducted dissolution test the tablet crumble into large particle and rotated under the paddle. It seems a invisible boundary block them to release.
In chemistry review they mentioned- "during review it was seen that as tablet density becomes very low or porosity very high, dissolution performance deteriorate"
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Has your pharmacotechnical development taken into account the properties of your active ingredient? and whether it is compatible with many aggregating and / or gliding excipients?
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Hi! I`ve got question about DESs. How can I proof the formation of DES? If speak about IR, which regions should I look at and which bands can indicate on the presence of hydrogen bonds? And one more question: the addition of water results full distruction of DES or water will only dilute DES? Is there any information about how much water I can add to the DES before it stop being DES and become "water and dissolved substances"?
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Dear Arina Levina thank you for your interesting technical question. The question would certainly get more qualified answers if you explained what you mean by DES. I had a hard time finding it out. When you check the Wikipedia entry on the abbreviation DES you find no less than 26 different meanings of DES on the English page, from "Data Encryption standard" to "Deep Eutectic Solvent" (https://en.wikipedia.org/wiki/DES).
Since you were talking about hydrogen bonds in your original question I assume that in your case DES stands for desloratadine, right?
In this context, please have a look e.g. at the following useful link which is freely available as public full text:
Improving mechanical properties of desloratadine via multicomponent crystal formation
For the stability of desloratadine in water, please also see the following relevant article:
Acid-base equilibria and solubility of loratadine and desloratadine in water and micellar media
It could also pay off to use the "Search" function of RG to find and access other useful references on this topic. Just search for "desloratadine" and then click on "Publications". This will result in a large number of interesting articles:
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I am looking for an article that talks about the direct interaction of a nanoparticle and sars cov-2, but most of the articles talk about target proteins attached to gold nanoparticles, but I'm only looking for the interaction of sars cov2 with the nanoparticles. but I can't find that paper if exist.
(am trying to see the interaction in a solution of gold nanoparticles stabilized with povidone to see if they form clousters or how they interact in general)
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Dear Juan carlos Dominguez Solis
Nanoparticle-Based Strategies to Combat COVID-19
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In Chemkin "Flame Speed Calculator", to analyze the flame propagation characteristics, we provide an initial temperature and pressure value. But the phenomenon of "spark-ignition" is not at all accounted for.
Although the chemistry mechanism input considers the chemical reactions taking place in detail, the dissociation effect by the electric  spark is not accounted for. How can this effect be studied?
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Hi Pranav, could you find the answer?
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We know that superplasticizers' properties vary in terms of PH, Density, Mass average molecular weight, Sidechain density of carboxylic acid groups, Impeller rotational velocity, Viscosity cP, and so on.
I wonder which type of superplasticizer can disperse Nano-SiO2 in water in the best way possible to make concrete?
Furthermore, is there any test that shows how well the nanoparticles dispersed in water?
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Interested question. In my opinion the best superplasticizer that can handle hydration processes under nano scale. In many cases capillaries filled with nano particles without any water reaching possibility. I think the best superplasticizer must manufacturing to overcome this problem specifically!. Then all nano materials react with Ca(OH)2.
My regards
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Does anybody know a good app for Android to visualize cif files?
We tried CrysX, but it shows the cell unit, and molecules look just weird.
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Dear Ekaterina E. Khramtsova please have a look at the following useful link:
Jmol: an open-source Java viewer for chemical structures in 3D with features for chemicals, crystals, materials and biomolecules
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Dear all,
Hope you are doing well.
I'd kindly like to ask if anyone may have any available internships/apprenticeships with regards to the field of research. I am a volunteer with IAESTE Malta and am currently in my second year completing a Bachelors of Science (Honours) with Chemical Technology where I place as one of the highest students in my class. I am looking for a 1-3 month period that focus' on spectroscopic technics or anything mycology and/or chemistry related.
I am asking here since I would like to have an experience outside of my country that would be both educational and enjoyable.
Anyone that may know of any offer and/or is offering one please leave a comment or email me through my student email: shaun.attard.e21254@mcast.edu.mt.
Thank you for your time and considerations.
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Hi Shaun! I'm not sure where you are located, but I would recommend researching Research Experience for Undergraduates (REUs) in the U.S. Many schools here offer a summer internship program for students from another school. I am unsure of their stance on international students though.
If you are a U.S. citizen, then I highly recommend looking into internships with NASA if they align with your interests. You can learn more about those opportunities at intern.nasa.gov.
You might look up some companies that you are interested and reach out to them specifically. The easiest way to do that might be to find employees of the company on LinkedIn and reach out to them. They might be able to point you in the right direction on how to get an internship with their company.
Good luck and I hope this helps!
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Hello everyone, my research is about leaching of gold from end-of-life printed circuit board by using Fe2(SO4)3 solution and the leachability was approximately 30-40%. Hence, i have some questions to ask.
1. Could these reactions be spontaneous in my solution?
Au + Fe3+ --> Au+ + Fe2+
2Au + SO42- + 2Fe3+ --> Au2SO4 + 2Fe2+
2. If not, in your opinion, what reactions might occur in my solution for gold leaching?
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Dear Natrawee Khetwunchai thank you for your very interesting technical question. Please find cited below some research articles in which the mechanism of gold leaching using Fe2(SO4)3 has been investigated:
1. Recovery of Gold from the Refractory Gold Concentrate Using Microwave Assisted Leaching
(see attached pdf file)
2. Bacterially generated Fe2(SO4)3 from pyrite, as a leaching agent for heavy metals from lignite ash
This article is freely available as public full text on ResearchGate.
3. Leaching kinetics of gold bearing pyrite in H2SO4−Fe2(SO4)3 system
(see attached pdf file)
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I am working with polyamine surface coating on bio-materials. I have seen in literature that microBCA detects the primary amine in proteins. Similarly, mostly peoples are using it for Dopamin's catechole amine estimation. I am wonder that the same way can I use microBCA for detection of polyamines coated on surface. However, I couldn't find the relevant literature.. I have checked my polyamine changes the color with microBCA and detected their OD values after coating but I am not sure this will be proper to show or not......
Your feedbacks will be highly appreciated
Thanks in advance
~Taufiq
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Hi Taufiq Ahmad . From literature, it looks like the BCA assay works only with secondary amines. As the secondary amines form a colored chelate complex with cupric ions (Cu2+) in an alkaline environment and form Cuprous (Cu+) ions. The Cuprous ions form a complex with the BCA assay.
In experience I have found a linear response of BCA assay with Primary amines too. I do not know what the exact mechanism is for that. Did you find it out?
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Can someone please recommend me a textbook for wastewater treatment explaining different techniques and their related physics and chemistry?
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Anurag Roy perfect question and you can surely have a look at this blog with many experts from around the globe and they will help you for sure
you can also find some books listed there too,....
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We are currently using Hemavet and Vetscan but they are both very old and we are looking to upgrade. Thanks!
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Thank you both!
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I am DO levels in stagnant waters from a stream mesocosm experiment. During the non-flow periods, DO saturation measurements are reaching maximums of 300% (26 mg/L, 21 degrees C). The flumes contained high amounts of filamentous algae and high light inputs, which might partially explain these values. Nevertheless, we are afraid that oxygen bubbles might be generating an artefact.
We are wondering which are the maximums levels recorded by other researchers in similar conditions?
Thanks all for your help and time,
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Hi Gregoire,
Thanks a lot for the information and the links! Really helpful!
Cheers,
R
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It sounds that shorter λ (more energy) makes the wave more powerful to go through a specific thickness of the material, but the weaker wave does it better. How are the interactions of the wave with the molecules?
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It is true that transparent materials may have imperfections that result in sub wavelength fluctuations in the density and produce Rayleigh scattering. For example, this is an important component of the transmission range in optical fibers. True also for molecular scattering in the atmosphere.
However, if you are asking about the penetration depth into a homogenous material with some degree of absorption, absorption is NOT described by Rayleigh scattering. Instead, see
Absorption is the resonant interaction of the EM wave with some allowed energy transition of the charges in the material that has a transition dipole moment. Because this is a resonance phenomenon the strength of the interaction, i.e. the absorption probability, can have a lot of shape as a function of wavelength (energy). Near a discrete transition the absorption may increase as you shorten the wavelength and then decrease again as the energy increases further past the absorption. (Absorption bands). The absorption probability results in a Beer’s law exponential decay of the field. So you can see the penetration depth may decrease or increase with shorter wavelength depending which side of a discrete absorption you are on. However, there is also an intrinsic inverse dependence on wavelength. (See wiki article) if the absorption is almost constant with wavelength (and so the complex index is constant) as is common above the band gap energy of semiconductors or transparent materials, the intrinsic 1/lambda dependence becomes apparent.
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Hello everyone,
I have a serious problem with coating the Pd/C catalyst uniformly on the glassy carbon.
I prepared the Pd/C ink by adding 20 mg of Pd/C into 9 mL of DI water. Then I sonicated it for 10 mins. I added 1 mL of IPA into the mixture and sonicated for another 10mins. I pipetted 5 uL of the ink on the center of glassy carbon (Diameter=3mm) and dried it in the air. To avoid any dusk from the air, I used a biker to cover the glass carbon. But I can't get a uniform layer of Pd/C catalyst on glassy carbon. Here is the picture of the Pd/C film. Can anyone help me with this problem?
Thanks,
Jay
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First I would like to ask you a question. I have doubt on the composition of your ink, how uniform?. If your ink preparation is not uniformly dispersed, your loading on GCE may not be uniform. Thus I recommend the following. Amount of catalyst to solvent ration (e.g. m/v), choice of solvent and binding reagents, cleaning GCE strategy and drying systems must be carefully manipulated. For example, if the catalyst added to the solvent system is too large, the distribution/solubility of your catalyst may not be good (try to tune this too e.g. catalyst/solvent ratio 1/1, 1.5/1 and so on). As recommended by other researchers please try ethanol as a solvent and Nafion as a binding agent, here the amount of Nafion also matters, to my understanding should not be higher than 30 μL to obtain uniformly coated GCE. Moreover, if you keep your electrode for long time on air for drying (after loading your ink), your electrode may not be uniformly coated too. Alternatively, you can use 40 or 60 oC oven for short time to dry your electrode with required amount of your catalyst (e.g. 5 μL on 3 mm diameter GCE). Hope this will help you a little.
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When I dipped a copper plate into a heated NaCl solution, a precipitate of copper was found in the solution.
What is the real chemistry behind this?
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Dear Asfak Patel thank you for your interesting technical question. It is known that the contact of metallic copper with sodium chloride solutions in the presence of oxygen (air) can lead to corrosion of the metallic copper. Did you check the composition of the precipitate?
For some general information about copper corrosion in NaCl solutions please have a look at the following useful articles:
1. Investigation of copper corrosion in sodium chloride solution by using a new coating of polystyrene/g-C3N4
This paper is freely available as public full text on ResearchGate.
2. Influence of pH and Chloride Concentration on the Corrosion Behavior of Unalloyed Copper in NaCl Solution: A Comparative Study Between the Micro and Macro Scales
(see attached pdf file)
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How the journal evaluators examine the work and the reproducibility of results?
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To ensure understandability, reproducibility, and replicability, the research methodology must be clearly spelled out and expatiated upon. In other words, all procedures carried out in a study must be explained in detail in the methods section, leaving no room for whats or whys. The following could render more insights.
PLOS. (2021, February 26). How to write your methods. https://plos.org/resource/how-to-write-your-methods/
USC Libraries. (2021, March 18). Research guides: Organizing your social sciences research paper: 6. The methodology. Research Guides at University of Southern California. https://libguides.usc.edu/writingguide/methodology
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Influence of ligand on an heterogeneous catalyst surface reactivity
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Thank you for sharing idea Madhukar Baburao Deshmukh
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Good afternoon, I am a student of ING chemistry, could you help me with information on the subject of Biorefineries for my thesis.
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Good afternoon Mrs / Ms.
What kind of the specific information you probably need ?
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I've been looking for some of these sporadically here and there, and have not had any luck. Trying to do SN2 chemistry with dichlorophenylphosphine to produce diaminophosphoranes. Specifically, I'm looking for anhydrous aniline.
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Jason Wilt, Because no one knows the degradation products have higher or lower boiling points than the mother amine, I recommend that you use at least two receiver flasks to eliminate both lower and higher bp materials together. Imagine you distill 25 mL, I usually take the first 3 mL and last 1-2 mL each in a same small flask together. Collect the first, low bp portion till the gas temperature becomes constant. Then, you will have a main fraction in a big flask. The gas temperature tends to decrease during the last half of your distillation, heat to keep the gas temp. It's time to stop collecting the main fraction and to change the flask to the drain receiver, if the gas temp. goes down even if the mother liquor is heated. After cooling the whole system to rt, introduce argon or nitrogen to the system, to break the vacuum. Do not dry up the mother flask. Stop the distillation before the mother, heated flask loses all the liquid, because there may be peroxides there. (Dried peroxides are said to be explosive sometimes when they meet oxygen, at high temp. That's why you should cool the system before stopping the pump. You also use argon not air. All of these avoid the danger.) Put a septum cap with an argon balloon to the main fraction, and by a syringe or a cannula, transfer the freshly distilled amine to ampules which are already dry and have argon inside. Close the ampules immediately by flame, and keep them in a dark fridge till you use them, after you warm up to rt. Refluxing with CaH2 for 1 h will usually be done before the distillation. Good luck!
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Hello,
Now a days, paralleling of batteries is being done among different chemistry of batteries. Suppose, if I connect lead and lithium batteries in parallel. What will be the current distribtuion and voltage profile of the system. I am searching for literature about it but could not find exact information.
Can some one help me?
Thanks
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Usually the elements are selected. Those, elements assembled in a group should not have very different parameters (for example, operating voltage, internal resistance). If, for example, during series connection one of the elements has a relatively high internal resistance, then it will limit the entire series, and so on. If you have access to a large number of same elements (for example, in manufarture), then it is not difficult to collect the required quantity for assembly, but with a limited quantity, this can be a problem. In the "professional case", the elements are connected in a circuit using active components to neutralize their differences, both initial and arising during the discharge process.
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My research deals with tertiary amine but my background is not chemistry, so I would like to learn more about amine. Any helpful suggestions will be highly appreciated. Thank you in advance.
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Dear M. Mozammel Hoque,
I think that Book Organic Chemistry Morrison & Boyd is good for you.
Kind regards
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When it comes to choosing a good journal, it has always been debated which one is more important? Impact factor (IF) or journal quartile (Q)?
I give an example, you have three following journals, which one would you choose?
1- IF: 1.3 & Q1
2- IF: 2.5 & Q2
3- IF: 3.9 & Q3
Please select one of the three journals above and give a reason for that.
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Thanks for the response. However, after considering all of the criteria you mentioned, we have to choose a proper journal for our paper.
Let me put the question in this way, what makes a journal better than others!?
In the main question, I gave three examples; could you please choose one of them?
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How can I get involved in writing an article with someone else?
Does anyone want me to participate in writing a review article?
How?
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I agree with you Mr. Naimish Kumar Verma.
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Is there a way to dope or combine the FeSe alloy onto a MXene (Ti3C2Tx) which can be used as a electrode for energy applications?
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Dear Lokesh Murali thank you for this interesting technical question. I only found a references in which the combination of nickel selenide with Ti3C2Tx has been reported:
Ultrathin Ti3C2Tx (MXene) Nanosheet-Wrapped NiSe2 Octahedral Crystal for Enhanced Supercapacitor Performance and Synergetic Electrocatalytic Water Splitting
This paper is freely available as public full text on ResearchGate.
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how can I find a common related project between chemistry (polymers or biomolecules) and mechanical engineering( for example fluid mechanics )???
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Something that has to do with study involving production of nanocomposites for the production of fire resistant parts or shear resistant parts of mechanical equipments.
Production of Biodiesel from non-edible composition of biomaterials by transesterification
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Hello everyone:
I am looking for a simple software program to model chemical bonds. The purpose is to generate a high-quality graphical abstract for a top leading journal in the field of chemistry. I am not interested in professional programs like Photoshop as I don't have enough time to learn. Any suggestion?
Thanks in advanced!
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Hello All
My question is how can we tell if one functional group of an additive is good for trapping charge (electrons) without causing charge accumulation ?
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Dear Gabris Mahamid thank you for this interesting technical question. As an inorganic chemist I'm not really familiar with this topic, but I can try to suggest to you a few potentially useful articles. Please have a look e.g. at the following papers:
1. Can a single molecule trap the electron?
This article can be freely downloaded as pdf file from the general internet.
2. Functional group dependent dissociative electron attachment to simple organic molecules
This article is freely available as public full text on ResearchGate.
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jcr based impact factor not the other one.
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bioinorganic chemistry and applications
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I'm Juan Carlos, a high school student who is working with electropinning, I made an electropinning machine with a 21g needle and a 30kv high voltage source and the distance between my needle is 5cm (these conditions are already complex that I would not like to know if in their research they obtained that the higher the density, the higher the high voltage must be or if there is any relationship because the electrospinning worked twice but I did not know the density (it was more than 20w/v) and now that I try to find the density trying No I can find it. the solution is pva,i already tried with 20,25,30,35,40 (w/v) without any dopand. i should tried with w/v less than 10w/v? (i dont have a bomb).you can check the video o from one of those times that worked. and the drop is de pva with silver nanoparticles.but now i only lokking for pva electrospining without something. the power supply is a half of medium wave rectified
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I think these attachments can be useful for you
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Hello fellow Template searcher,
I was looking for Analytica Chimica Acta Template but I could not find it anywhere. So I decided to make one my own and share it. Enjoy all the styles that I have created.
This template could work for most Elsevier journals.
Thanks,
Viraj G.
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Some Oxford Nanopore kits have Primers with 5 ' modification that provide ligation to adapters without the need for ligases (ligase-free method), as in 16S barcoding kits. Does anyone know what modification this is or the chemistry involved in the process? I'm very grateful if anyone can help me with this information. Thanks.
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I am guessing some kind of click chemistry so some kind of amide or alkyl group that would then be complementary to group on what you attach to.
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Does anyone has an experience with sodium tert-butoxide? How dangerous it actually is?
Do I need to use a glovebox while weighting and handling it?
Do I have to dissolve it in THF at -30C or room temperature will also do?
How do you store it after the can is opened?
We have 100g of sodium tert-butoxide in total, the planned amount for my synthesis is ca. 1.5 g.
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A safety data sheet (SDS) from one manufacturer attached. This material is very high risk and requires special handling and storage. It does not say on the SDS that it is incompatible with organic peroxides, but in contact, it will release hydrogen gas. I would recommend looking for a safer substitute if possible.
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I am interested Research in Glass Chemistry. Expert should please drop information here on where i can have the best supervision, studying under an expert in this aspect of Chemistry.
Thank you
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The University of Jena, Germany, and the New York State College of Ceramics at Alfred University, in the USA, are among the most specialized and traditional centers in glass science.
The Federal University of Sao Carlos, in Brazil, also offers very equipped facilities, if you prefer a tropical country.
Of course, there are a lot of other good institutions... it depends on the subject you are interested in within the topic of glass chemistry. For example, if you want to research Bioactive Glasses, the Imperial College London has nice researches in this field.
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Hello, I am a 3rd year chemistry student and I'm writing my project report on computational chemistry. does anyone know how PBEsol improves upon the PBE functional?
Thanks in advance
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Both the PBE and PBEsol are first-principles generalized gradient approximations (GGAs). A simple modification of PBE is the PBEsol functional, which differs from PBE only in two parameters, and is designed to improve upon PBE for equilibrium properties of bulk solids and their surfaces. The main difference between them is that they are based upon different selections of exact constraints to satisfy.
At the GGA level, but not at the higher meta-GGA level [Meta-GGA DFT functional in its original form includes the second derivative of the electron density (the Laplacian), whereas GGA includes only the density and its first derivative in the exchange-correlation potential], one can at most satisfy two out of the following three constraints exactly:
1. second-order gradient expansion for exchange.
2. second-order gradient expansion for correlation
3. the local spin density (LSD)-like linear density response of a uniform electron gas.
The PBE satisfies numbers 2 and 3 but not 1, whereas the PBEsol satisfies number 1 and compromises between numbers 2 and 3.
From the performance perspective, the PBEsol describes more correctly the stereoelectronic (SE) effects in many hydrocarbons than many other DFT functional approximations, applies to densely packed solids, and is also useful for large organic molecules (in the absence of free atoms). On the other hand, although no GGA without a dispersion correction can account for long-range correlation, the PBEsol (after the error cancelation between exchange and correlation) can apparently account for medium-range interaction better than the PBE.
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I am working on polishing abrasives. I need to do few characterizations ? which can provide the on time surface chemistry of substrate with polishing abrasive during optical polishing. I would also like to know the physics behind it.
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The best way is to measure X-ray or electron diffraction accomplished with photoluminescence. It will give both insights into the nature and the quality of surface improvements.
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In what case would a reaction rate always show direct relation with activation energy or would it always be an inverse relation? Is it a indirect relation, inverse relation or both case can hold? (Please provide supporting resource, thank you).
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Nobody forbids anyone to look for and use other relationships of rate constants on temperature than the Arrhenius equation. In design, it does not matter whether the equation/function used has a physical meaning or is merely an empirical equation. In science, however, one should not assign physical meaning to equations and thier parameters that they do not have. Unfortunately, this is a common procedure.
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I have produced oleum by adding sulfur trioxide, SO3, to sulfuric acid. It mostly contains disulfuric acid (also called pyrosulfuric acid) but i think this method is not suitable for laboratory purpose so is there any feasible procedure for the synthesis of oleum for laboratory purpose?
Suggestions will be highly appreciable.
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Dear Daniyal Ahmed just in case that this question is still of interest to you: The article cited below contains a detailed description of how to make oleum in the laboratory:
Preparation of Sulfur Trioxide and Oleum
Personally I would suggest to buy oleum from commercial sources as it is an industrial product manufactured on a large scale.
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Can anyone recommend some any software/models available that can predict substance reactivities and the reaction yield under a specific set of reaction conditions process and proposing pathways to synthesize target molecules from a complex mixture?
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Dear Talal Ashraf there are two potentially useful article on this topic available as public full texts right here on RG:
1. Predicting Feasible Organic Reaction Pathways Using Heuristically Aided Quantum Chemistry
2. Neural networks for the prediction organic chemistry reactions
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Chemistry is frequently termed the "central science". As such, chemistry is expected to play a major role in fighting the coronavirus. For example, hand sanitizers and drugs are all based on chemistry. What contributions can chemists make to fight COVID-19?
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Full discussion of this project topic
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Follow
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I am working on my research proposal on the topic, "physical proximity and technology-enhanced collaborative learning in Chemistry. And am going to use the topic matter and change, using CK-12 foundation.
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Hi Leonard, I would suggest you search review articles on your topic first, journals like the Review of Educational Research could be a good start to find the foundation studies for your proposal. Good Luck with your research proposal!
-Tingting
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So I know some metal-insulators (ex VO2) have thermochromic infrared-reflective properties, but most of these are insulators at low temperatures and conductive at high temperatures. Some perovskites conduct at low temperatures and insulate at high temperatures, but I haven't found any that show significant thermochromic properties and have a transition around 10C. Does anyone know of materials that satisfy these criteria? The temperature range doesn't need to be exact.
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Dear Ethan,
There is a similar question which were posted in the research gate forum. This could answer your question. Please see the following link
Best wishes
Xuhua
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Hello,
I‘ve got a problem that bugs me for two weeks now but I‘m clueless as to how to calculate the pH so I hoped someone here could assist me. Say we have got a salt made of of a weak base (pkb = 9.37) and a weak acid (pka = 3.98) with a molar concentration of 0.06M and then add an excess of the said weak base (additional 0.02M), how would I calculate the overal pH as I cannot apply the Hasselbalch equation.
Thanks very much in advance.
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Since the pKa's of acid and base are far apart, you probably start with a near neutral solution before you add the extra weak base. Then you pH goes up into the alkaline area.
Normally you prepare a buffer by either using a weak acid and adding about half of its concentration of a strong base or vica versa. I do not understand that you call a mix of a weak acid and a weak base a buffer.
What is the purpose of your 'buffer' ?
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When I tried to mix a sodium metabisulfite solution with sodium hydroxide solution, the mixture solution quickly became turbid. Before mixing both were clear solutions. Please help explain the chemistry for this observation?
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Sodium metabisulfite (Na2S2O5) dissolves in water as sodium bisulfite: Na2S2O5 + H2O → 2NaHSO3. Sodium bisulfite is converted to sodium sulfite (Na2SO3) by
NaOH. The solubility of sodium sulfite (Na2SO3) in the alkaline solution may have been exceeded due to the common-ion effect, as Na+ is also contributed by the NaOH aq. sol.
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i am trying to formulating one formulation but the problem i am facing is after formulating and adjusting it's pH, when i try to check pH after 7 days it is getting down towards the acidic side.
How can i stop this? which buffer or combination of buffers i can use ?
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Ok sir !
Thank you and will update you too..
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I want to know about nanotechnology from beginning to professional. Thus I want some book in this area
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Dear Dr. Shafeek Buhlak ,
I suggest you:
-Advances in Nanotechnology and Its Applications
Ahmad Tariq Jameel and Abu Zahrim Yaser Editors
Publisher: Springer Verlag, Singapore
Publication year: 2020
ISBN 10: 9811547416
EAN: 9789811547416
-Nanotechnology
Paresh Chandra Ray Editor
Publisher: Nova Science Publishers Inc
Publication year: 2018
ISBN 10: 1536138894
EAN: 9781536138894
My best regards, Pierluigi Traverso.
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A question is about positron chemistry. Does the pH of an aqueous solution affect the lifetime of positronium (Ps)? The following references reported that the interactions between Ps and MnO4- was almost the same at pH=2, 7 and 12.
Are there any other similar examples? I wonder if it is correct to assume that the lifetime of Ps is unaffected by pH. Or conversely, are there any reports that the lifetime of Ps changes with pH?
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Thanks for the multiple replies.
The probability of pick-off annihilation in positronium (Ps) is primarily due to electron density, as Rüdiger Mitdank has pointed out. It is described by the overlap of the positron and electron wave functions. However, in practical terms, it is not determined by that alone, but is also affected by various environmental factors. In this discussion, I would like to get into these factors.
For example, water and many other liquids expand as their temperature rises. Since expansion decreases the molecular density (electron density), it is assumed that the higher the temperature, the longer the Ps lifetime. However, this assumption is not true. In fact, the lifetime of Ps is shorter in warm water than in cold water.
Similarly, the relationship between Ps lifetime and pH is not easy to estimate. Therefore, we should base our decisions on experimental data.
Most of the basic Ps chemistry was done in the 1960s and 1970s. In those days, the resolution and stability of measuring instruments were not as good as they are today, and the use of computers was limited. Straight lines were drawn with a ruler on hand-drawn one-log graphs. Therefore, the environmental factors that were reported to be "independent" at that time may or may not be due to the lack of measurement accuracy. As the application of positron science to medicine has progressed, motivation to revisit some of the issues has arisen.
I hope somebody will continue to let us know if you have any information on the relationship between pH and the lifetime of Ps. Thank you very much for your time.
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Its a colloidal solution of nano materials and AlF3 forms during the reaction and its still exist in the sample even after water washings.
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Try to reduce pH of the solution. May be it will help.
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I am using finite difference method to discretize the parabolic equation (explicit method), but confused about the chemical reaction term. Solving the generic equation for i specie involves a couple of species in the kinetic reaction equation since it is reversible ( Ex: A+B <-->C ). What is the best way to conquer the complexity in this manner? should I go with separation method and solve diffusion and reaction term separately. I am not quit sure if it is applicable. Thanks in advance.
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Kafia Oulmi Thank you for the recommendations.
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The oxidation of chloroform is dangerous because it results in phosgene formation under exposure to UV light. Along with the minimization of UV exposure, this reaction is usually prevented with 1% ethanol by mass (or less commonly, amylene). I find this information everywhere online, but never find a clear explanation of why this is the case.
Since isopropanol is so similar to ethanol, how come people don't use it to stabilize chloroform? Does it not work? Is it because its less volatile than ethanol? Does the prevention of phosgene primarily work in the gas phase?
Also, what would happen if the concentration of ethanol was increased from 1% by mass? What would be the problem with this aside from purity concerns? Would the same concerns apply to isopropanol if it does stabilize chloroform?
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Thanks, Jukka. I've gone with ethanol to be safe.
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To date, I have had the opportunity to explore several open source and private software like MFiX, Fluent, Sim-flow, Barracuda VR, PHOENICS, etc. I want to investigate 3D, hydrodynamics (include particle behavior), chemicals and radiation heat transfer maybe.
But I saw different problems when I tried to importing geometry as STL on each software.
Which software are you using when you solve this type of analysis?
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Timothy Braun I am using MFiX for several months and I saw a Barracuda VR. But some reasons (like a budget :) ) I couldn't use a Barracuda.
Each software have different pros and cons for MPIC schemes. Firstly, MFiX is open-source and you can change everything that you want (like a user-defined-function). Also, MFiX has some different discretization schemes, solver types, etc.
Btw, Turbulent solvers are different. I'm working on turbulent case and chemical solvers these days. It seems Barracuda is beginner user friendly, but need to time for learning advanced things for MFiX.
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I was asked to include Stewart acid-base chemistry into a lecture I have and then I became very confused when I tried to read about it. It is there stated that it is the ion gap between positive and negative ions that creates pH changes by interacting with water. A negative value will for example lead to that H+ is donated from water to neutralize the charge difference. What I do not understand here is that it is impossible to take H+ from water without creating OH- at the same time. This would violate the law pH+pOH=14 and it will also not help to neutralize the charge difference. Is there anyone else that understands where OH- go in this case? Is it going to neighboring tissues?
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Thanks a lot, it was interesting to read it, but it still did not answer my question about OH-. I feel more and more that nobody knows. One option could be that the OH- goes into the tissues but it is silent about it because it is very difficult to measure. I cannot really see any other solution.
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Is it possible to calculate entalphy of LiBr/H2O or another solution if we know correlation of specific heat without using any software?
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If you want to solve your problem as it appears in the image, I recommend using an equation of state for the enthalpy departure.
I also recommend the following articles:
-A computationally effective formulation of the thermodynamic properties of LiBr-H2O solutions from 273 to 500 K over full composition range
- Exergy calculation of lithium bromide-water solution and its application in the exergetic evaluation of absorption refrigeration systems LiBr-H2O
-Thermodynamic Evaluation of LiCl-H2O and LiBr-H2O Absorption Refrigeration Systems Based on a Novel Model and Algorithm
-Mathematical Model of a Lithium-Bromide/Water Absorption Refrigeration System Equipped with an Adiabatic Absorber
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What happens when HF and SiO2 react? Will other toxic / hazardous substances be created as a side product? Thanks!!
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Dear Huyen Tran Dang to my knowledge the formation of difluorosilane, SiF2H2, cannot be explained by the reaction of SiF4 with HF. The latter two compounds will react under formation of H2SiF6 (see e.g. the link cited below). I think that the formation of SiF2H2 can only be explained by the presence of elemental hydrogen, H2.
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In a few reference books of environmental engineering is mentioned that maximum acceptable concentration of nitrate is 10 mg/L as N. What's the meaning of "as N" in this unit of measurement? What's the usage of it?
Thanks for your assistance
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Hello Mr. Hajipour
"N" refers to a molecular nitrogen presents in a defined concentration of a molecule or ion. You can find it out by multiplying the molecular weight ratios.
In your example if N in the form of nitrate (NO3^-) is 10 mg, then the concentration of nitrate molecule will be 10 mg N*(62 mgNO3/mmolN)/(14 mgN/mmolN), i.e. 44.28 mg NO3^-.
Same concept is valid for any other atoms and molecules.
Regards
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In the structure of many drugs, there is a carboxylic group
What is the significance of this group? Why should it exist in the structure of a drug?
Do you know any article or book or reference about this subject?
Thanks a lot
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In all metabolic processes in nature, electron transfer takes place at the molecular level. Two fundamental atoms in all living entities are oxygen (O) and nitrogen (N). In direct combination, they form NO, which is one of the most crucial biomolecules because it has a free electron ("free radical"). It is part of a universal communication system in biologicals cells.
If we go one level of abstraction higher, we find the amino (NH2) and the carboxyl (COOH) groups. In the carboxyl function, the electrons can migrate from one O to the other via the C atom (mesomerism). Thus, the H atom can easily migrate to the "partner" NH2 - the electrons are "free" and can participate in biological processes.
It is also why phenols, especially polyphenols (green tea EGCG, resveratrol, quercetin), are biologically very active. If both functional groups occur within one molecule, we have one of nature's most essential building blocks, amino acids.
With more atoms and larger molecules, the electron transfer becomes more complicated, but it can explain almost any drug's mechanism of action. It is perhaps interesting to note that electron transfer within biomolecules is sometimes completely different from what we know from the chemical laboratory.
That is why "free radicals" in the body are not generally harmful but vital.
SUMMARY
In summary, it is one of the most important functional groups in nature. That is the reason why it occurs as a functional group in so many drugs.
Attached you will find a link to a paper describing the effect of some functional groups in drugs.
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The common method for phosphorus solubilization efficiency measurement of soil microbes is zone formation in agar media (generally Pikovskaya media) but this is a qualitative study. However, there is also a liquid culture method with insoluble phosphorus in liquid media. The estimation of available phosphorus by ICP-OES is quite promising and precise.
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But ICP-OES is a costly instrument and therefore available in a few research laboratories of third world countries.
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The cleavage cocktail is composed of Phenol/thioanisole/water/TFA/triisopropylsilane. I only prepare 10 mL cocktail per peptide but can the activity of the cocktail prepared at 100 mL last for a week?
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Hi Simon, I have used many cleavage cocktails and scavangers for peptide cleavage. My opinion: The cocktails aren't that stable, especially the TIPS and thioanisol. Maybe one week is fine if you keep it in the freezer. I would recommend to start with a fresh cocktail each day for best results.
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I prepared PVDF in a very regular way by dissolving it with stirring at room temperature
but when i placed it in vacuum for eliminating the bubbles and trapped gases it started to burst and splash
Does it happen that one has experienced this as well
Is there any reason for this behavior ?
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Dear Prof James
thanks for sharing your nice answer
Heating is to be done
I only want to get rid of the trapped gas and bubbles first
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Hi,
I'm a student in an engineer school in chemistry. I have to do some research about encapsulation for pharmaceuticals applications.
However, there are 2 characteristics about capsules that I can't find anywhere...
What are the thickness and porosity required for capsules for pharma. applications ?
Thank you in advance,
Have a good day !
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Thanks for your answer !
Samer Adwan
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To have the desired grain size in 6061 and 6063 Al alloy, what should be the minimum % of Ti and B pick up and what is the chemistry/metallurgy behind that?
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5%Ti 1%B add as a master alloy of Aluminum in wieght ratio 100:1 Kg
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Any significant progress in the design or innovation of solid catalyst for biomass hydrolysis and sugar fermentation into alcohols in a biorefinery? If yes, I would like to have some recent updates regarding that subject. Thank you all
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I think the main established routes employ biochemical catalysts. I've been working in this area for more than 7 years and I haven't heard of any new developments in solids catalysts for the saccharification of lignocellulosic biomass. Enzymes are very specific and productive towards breaking glycosidic bonds. Enzymatic reactions also require mild reaction conditions such as low temperature and mildly acidic pH.
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Hi everyone,
I am doing an allantoin assay in urine and all the protocols seem pretty vague. I am currently using this website which seems to be the most helpful:
It mentions that I use 15 mL tubes, but since I am boiling the samples should I use glass tubes with a cap to prevent escape? Or can I just use plastic tubes like the ones here:
Thank you!
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Nice question
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Is any way or method to seal agarose pad or channels fabricated agarose gel pad to glass slides as like we do plasma bonding with PDMS to glass slides?.
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Good question
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Polyethersulfone membrane are generally hydrophilic. How can I explain this in terms of chemistry, molecular structure and functional group?
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Dear Sweety Rani, to a very low extent because of the hindrance of two bulky neighborhood benzene rings. Chain stiffness and compactness reflected by high Tg limit (almost excluded) diffusion at ambiant conditions. These are the main reasons behind PES chemical modification. My Regards
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For those of us in chemistry, environmental science, civil engineering, industrial chemistry, analytical chemistry, chemical engineering, biotechnology etc this paper might be helpful. Link is below
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لم استطيع التحميل
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im looking for a diy at home (home lab) molecular magnet in a chemical suspension that is stable at room temperatures and cheap
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Mr. Solis,
What you shall synthesis in your home-lab? Something for the market in United States?
Have you decided to compete with Colombian home laboratories; and reagents in Mexico are freely available in stores?
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Need to form uniform coating of ZnO with readily available ZnO powder on a substrate. So which liquid solvent I need to use and which procedure I need to follow to prepare such solution? Very new to field of chemistry. Please help
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we have ZnO powder, how can i coat on glass or ITO substrate
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It is known that scientific knowledge is replicated each time at more unusual speeds, however, humanity expects more from our scientific work, that is, solutions to problems that have accumulated and that it is necessary to solve to improve the quality of life . It would be good to reflect on those expectations.
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The experience of the development of science shows that the quality and significance of a scientific discovery and its usefulness or harm for human civilization are inversely dependent on any expectation, be it the expectations of the entire scientific community, and even more so the expectations of a "non-professional" society. For example, it is known that the great Rutherford, who discovered the atomic nucleus, believed that his discovery would have no practical application.
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Environmental pollutants and hazardous are major issues through which the modern world. Among all the environmental pollutants and hazardous materials how much contribution is from chemists (out of 100%) lets put rough estimate.
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I think you mean to say the amount of emission by pharma sector. There is no study available but pharma industry is one of the major contributor of pollution. Pharma market is 28 per cent smaller yet 13 per cent more polluting than the automotive sector
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Environmental pollutants and hazardous are major issues through which the modern world is suffering. Among all the environmental pollutants and hazardous materials how much contribution is from chemists (out of 100%) lets put rough estimate.
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The answer to this can be very subjective. It is like saying how much of polution comes from airplane pilots. I have no data to support this but let's try common sense: most human waste comes from factories, mining, transport, institutions and households. There has to be a line between processed and unprocessed waste. If your question meant chemists in academia then I would say it is negligible (<<1%). But if you want to highlight it based on potency, that number can increase if you take subcategories of chemicals only produced in lab.
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I have been thinking about a material that was made 6 months ago, which is a tetramethylsiloxane linked to a thiazolidinedione and finally to a naphthalene, but I can't find the original paper (if someone can find it please tell me) but that material had a time of duration of 2 hours until the bond of thiazolidinedione to naphthalene is broken and the material is no longer hard but I know it is an isomeration but the bond does not know why it occurred, could someone tell me that defines the time of the bond in molecular switches or is there any related role please?
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I may need more information to answer your question. However, you may read my paper to get an idea of how molecular motors and switches work.
1. Proton‐Gated Photoisomerization of Amino‐Substituted Dibenzofulvene Rotors
2. Synthesis and Photoisomerization of Substituted Dibenzofulvene Molecular Rotors
We discuss this aspect in detail.
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I have a difficult to dissolve drug, previously I used DMSO to dissolve it but I want to avoid the toxic effect of DMSO, so I am planning to dissolve it in methyl-cellulose and use tween 80 to emulsify it. Can I prepare it and use it within a week or should I prepare it everyday and use it freshly.
Thanks a lot,
Sarah
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We have used this technique for one drug and confirmed stability for 12 months at 20C but it is impossible to generalise. Stability will have to be established for every individual drug and set of conditions I;m afraid
.
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Greetings
Which of the following majors is more suitable for studying at international universities for the master's degree in chemistry? Please apply the following items in your final answer: 1- Average income after graduation in the United States or Europe and 2- Ease of admission to international universities 3- Number of jobs available after graduation 4- working in the field of medicine and pharmacology etc.
  • Medicinal chemistry
  • Organic chemistry
  • Pharmacology
  • Nano Chemistry
  • Analytical chemistry
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Hi
As for your Expectation, Analytical Chemistry will be the best option.
Chemistry, Biochemistry and Biotechnology all need Analytical Chemistry - tough than other subjects.
Next Organic Chemistry
Study Analytical Chemistry and contact me for better position in US
Best Regards
- Saranya Bharathi
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Dear colleagues!
At the moment we are looking for "nice" reactions employing BuLi solutions for our practical training at the university. We aim to expand our five standard BuLi reactions to a broader field.
Therefor if you know suitable reactions for that purpose please write a short answer. Links or literature citations are also welcome!
"Didactically valuable" reactions with simple starting materials would be of special importance.
Thank you very much!
Eric Täuscher
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Dear Eric Täuscher here is another interesting paper by the famous henry Gilman entitled "Color Tests for Some Organolithium Compounds"
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Could the presence of ligand on a catalyst surface reduced the reactivity of its surface? If yes/no, please explain why?
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this depends on which type of ligand used
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Recently, I came into contact with a new discipline named chemo-mechanical coupling. I found that chemo-mechanical coupling phenomena exist in many research areas, ranging from development of advanced batteries, biomechanical engineering, hydrogen embrittlement, and high temperature oxidation, etc. Although it is very important in engineering field, I can't know the main mechanisms of coupled chemical and mechanical interactions. Can you give me some suggestions? Such as, some related publications or research project. Thanks very much.
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Dear Gang Zhu
The applications of chemo-mechanical coupling discipline are going on for the time being into two directions that covering by materials research and development activity:
Designing and manufacturing a multifunctional components that characteristics in a variety of applications e.g. artificial organs.
Highlight the mechanism of material degradation and failure case study e.g. high temperature oxidation process.
Now, in the case of high temperature oxidation the mechanical coupling with the oxidation chemical reaction results in stress generation in the oxide scale formed which in turn affects the chemical reaction rate and the diffusion process of the reactants and therefore, the process become a complex chemo-mechanical as the stress is diffusion dependent during the oxidation and the oxide growth is stress induced.
In other hand, the story may be different with the hydrogel coupling behavior as external mechanical load can induce redistribution of ionic concentration, while a chemical stimulus lead to swelling or shrinking of the hydrogel.
So for this multi-field coupling behavior in a medium, there are many approaches that have been proposed by many researchers leading to a bundle of knowledge for the same coupling behavior .Thus, I think that makes the topic appears as foggy to understand by many of the followers.
I hope the above contribution is helpful.
Best regards
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How have collegues overcome inertia to the introduction of alternative practical procedures in high school/seconday school chemistry lessons?
These are difficult times for presenting practical work to students in schools. Social distancing and cleaning of equipment to reduce the spread of the virus has meant that the amount of student practical work has been reduced, even stopped in some schools in the UK. By alternative procedures I mean microchemistry techniques, “green” chemistry alternatives and specific practical designed to challenge the misconceptions which abound in our subject. Misconceptions arise because we are dealing with particles, which are so small they are invisible to the naked eye, which may be electrically charged and are in constant random motion, colliding with each other..
Reasons provided by teachers involve constraints set by National Exams, bought-in courses, Textbooks, lack to continual professional development (CPD), cost of equipment and chemicals, lack of inspiration and encouragement from education manager and suitability of the room being used. You may suggest more.
Do you finding writing in peer-reviewed Educational Journals useful?
Do you find non--peer reviewed social media such as Twitter or Facebook, reaches far more teachers and has more impact than Journals, becaue it is short snappy and attention grabbing.
I would like to hear your views.
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Since the emergence of digitalization, we are moving more and more towards “a machine for every process or problem” This is good for achieving efficiency and effectiveness and for large unimaginative technology companies that follow a marketing strategy as ”convenience suppliers”. However, in school pupils should learn fundamentals of processes. In micro chemistry there is basically no difference between traditional chemistry except scale. So, if you can’t see particles you may be able to precipitate, to concentrate, to color, to separate in order to make them visible. Under Corona condition you don’t have to do that in a lab – you could ask kids to do that at home in their kitchen with household equipment.
I am also amazed that in high-school environments pupils are not taught about the most important purification-separation technologies. They grow up without understanding that today we separate any mixture into its individual particles or molecular components. And so, they do not understand that we should not cheat or lie because we can trace any evidence say in biology, forensics, analytical chemistry etc. The excuse of “too expansive” we are currently addressing by creating a low-cost chromatography instrument for schools. (see https://www.chromatographyshop.com/product/scholar-lc-system/ ) We are preparing easy to handle instructions and experiments that are relevant in our time and exciting. The idea is to get the pupils to do the experiments. Environmental education is best done by involving scholars to change the world.
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In my personal experience I have find the higher rate of sprouting when fresh cow dung is applied on the top side of cutting what might be its reason.
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Thanks a lot, dear professor Madhukar Baburao Deshmukh for your nice answer
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I'm writing a chapter about the nitrogen cycle and discuss the different forms of reactive nitrogen such as NO3 and NH4. I also have some soil places where I discuss soil cations and others where I discuss plant nutrients such as "In a study with Sphagnum spp., Ca and Mg foliar content decreased as N deposition increased..." When should I show ionic charge? Thanks.
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Indeed, a good point. I see papers like:
Cole, J. C., Smith, M. W., Penn, C. J., Cheary, B. S., & Conaghan, K. J. (2016). Nitrogen, phosphorus, calcium, and magnesium applied individually or as a slow release or controlled release fertilizer increase growth and yield and affect macronutrient and micronutrient concentration and content of field-grown tomato plants. Scientia Horticulturae, 211, 420-430.
were the ‘formal’ notation is ‘loosely’ used. I think everybody understands that when talking about Mg content in these type of studies is actually Mg2+.
Personally, I would use Mg2+ as much as possible or talk about Mg ions, but I can imagine that in other disciplines other notations are tolerated or simply more costume.
Best regards.
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I have a 200 mg/ml ampiciline solution, how much should i add to 300 ml of LB medium to get the final concentration of 40 ug/ml?? How much bacteria (in ml) should i add to 75 ml of medium to dilute the culture 50 times??
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1. C1*V1 = C2*V2
200 mg/ml * V1 = 40 ug/ml * 300 ml, or V1 = 0.06 ml (of ampiciline)
2. If you mean 75 ml is the total volume of final medium, then:
C1 * V1 = 75 ml * C1/50
V1 = 75/50 = 1.5 ml (of bacteria)
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Hello everyone,
I have 5 Samsung 21700 - 50 E (NCM chemistry) cells. I want to do basic charge and discharge by connecting it in series. Does anyone know if there is a cell holder available online for single cells? Or how to connect these cells and make contact?
Thanks in advance
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I totally agree with you
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I need to get BrHPP for expanding Tgd cells, so if anyone knows about a biotec/chemistry company that has it commercially available I would appreciate the information.
Thanks!
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INNATE Pharma (Marseille, France)
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Study of different types of high school chemistry teaching methods in California
Or Texas or other states
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It varies from school district to school district but typically qualified Chemistry, Physics and other sciece teachers are hard to find. When they get somebody they try to keep him/her and if they can't find anyone the teacher and students learn the subject together.
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Hi every body,
I have tried to synthesis aliphatic isocyanates from their acylazide compounds based on Curtius rearrangement. Based on articles, the converting of acylazide to isocyanate must be done through a simple thermal treatment in toluene or benzene at 1-2 hours and via the evolution of nitrogen gas during reaction. However, I have repeated it many times and no isocyanate is formed after reaction. Could you please share your experience with me?
Unfortunately, I found no repeatible results from articles.
Thanks in advances
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Dear, did you characterized the product? This reaction requires a rigourous anhydrous conditions. May be the solvent is not dry enough. If this is the case, the NCO formed will immediately converts to an amine. My Regards
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Good evening,
I am looking for methods according following topic:
Vegetable oil (raps) contaminated with hydrocarbons (e.g. motor oil) shall be purified and separated from hydrocarbons. (Usage for in-situ soil remediation)
Thank you all in advance, I am looking forward to your ideas and suggestions.
BR Paul
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You can use Soxhlet or Soxtherm to separate oil by solvent extraction process and Hexane/ Methanol/ Acetone as a solvent.
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How is chemistry taught in schools in the United States?
A comparative study of high school chemistry education
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