Chemistry - Science topic

I am searching for a chemist working in organic chemistry field for cooperation ?

I am writing my thesis about metabolomics, and after reading about metabolites and proteins and how these have been measured through time for characterization and kinetics, I think metabolomics could be the one analytical technique that enables universal measurement of all intracellular, and possibly extracellular molecules. Even proteins with intact protein mode, for example. Maybe I'm too naive and inexperienced, and saving for some differences to enable separation (column chemistry), and ionization (ESI v APCI v direct injection), what are your thoughts on this statement?

I understand vaguely that the first author is supposed to be the one who "did the most work", but what counts as "work" in this comparison? Does "most" mean "more than all the other coauthors together" or just "more than any other coauthor"? What happens when the comparison is unclear? How often is "did the most work" the actual truth, versus a cover story for a more complex political decision? I realize that the precise answer is different for every paper. I'm looking for general guidelines for how an outsider (like me) should interpret first authorship in your field. Pointers to guidelines from journals or professional societies would be especially helpful.

Considering the context of the COVID-19 pandemic that requires remote teaching activities. In the case of Chemical Education, which requires a high degree of abstraction and the use of visualizations can effectively contribute to the student's learning process, how does the teacher deal with the relationship of macro, micro and symbolic representations, in online teaching?

kindly give the software details and download link

Much has been said about the differences between physics and mathematics, but less attention has been paid to the differences between physics and chemistry. The question is, where does physics and chemistry work?

As a requirment in my project, I have to synthesize Formamidinium bromide (FABr). According to the protocols which are mentioned in the articles, I've synthesized this material but I think there is an error in my work? Does anyone has the experience of this synthesis? Because in the articles, the authors don't express all the steps, I want to know if there is any critical strategy during the synthesis of FABr and specially in the purification stage of this process. I would appreciate if you point out a reliable article which has mentioned all the stages of this synthesis with it's details.

Hello, I need to impregnate the pores of a MOF with cu(acac)2, which I will then reduce under vacuum to copper nanoparticles. I plan on using the incipient wetness approach to do so. However, my MOF will not be in a powder form, but rather a self supported, fibrous mat form (Flexible Self-Supported Metal-Organic Frameworks Membranes w... ). According to my current research, the solid support catalyst (MOF) is typically stirred as the metal precursor solution in chloroform (or other solvent) is added to it, yielding a paste. However, I cannot stir my fibrous mat. Will simple immersion of my mat in the metal precursor solution be sufficient to impregnate the pores of the MOF with the precursor? Or would a drop-wise method of adding my solution work without stirring the MOF? Is there another way around this issue? Thank you for any answers!

Does anyone know of, or use, commercially produced surfaces for contact measurements (control material)? As an example, is there a producer of PTFE discs with highly controlled surface roughness and chemistry that I can purchase? I have not found any....

Several studies on combustion of bio diesel/petroleum fuel blends in IC engines and other power generation / combustion devices discussed extensively about the influence of fuel unsaturation on NOx emissions. A fundamental question arises on how we quantify fuel unsaturation? I would like to start a discussion on the topic - How to quantify fuel unsaturation ? what would be an appropriate index to quantify unsaturation irrespective of the family of origin of fuels - like methyl esters, ether, alcohol , alkanes, alkenes, alkynes or aromatics or a weighted combination of aforementioned categories. Our research group's take on this - We have established a parameter - Degree of unsaturation that serves as a common platform across different fuel families (esters/alkanes/aromatics) to quantify the effects of fuel unsaturation, particularly with petroleum/bio-diesel blends. DOU can be evaluated based on the average molecular formula of the fuel alone without involving complex and expensive experimental procedures such as those involved in the measurement of iodine number and bromine number. If interested, please follow the link to access the research work we have conducted at our laboratory to investigate the effect of fuel unsaturation on nitric oxide emissions. Effects of degree of fuel unsaturation on NOx emission from ... Experimental correlation of laminar flame pollutant emission... Message me to get a copy of this article.

I am wondering why some stains do not work by themselves and absolutely need to be paired with a counterstain to work. What is the chemistry behind this process? Is there a nice book that explains this process in depth? Thank you very much for your answer in advance.

Hello researchers,

Hello everyone, I do calculations on compounds with about 25-30 atoms (hydrogen, carbon, oxygen) and about 110 electrons in a water solvent (SMD solvation model). These are optimizations and frequency calculations. I'm searching for the best reference method I could compare results with. These systems are being calculated with B3LYP/6-311**G(d,p), B3LYP/aug-cc-pVDZ and B3LYP/aug-cc-pVTZ. I was thinking about CIS/6-311++G(d,p) but have found it's not the best pick - it's barely accurate when calculating frequencies. So I came up with an idea to recruit CCSD/cc-pVTZ, though three things are running through my head: I don't want calculations to run for more than 1 week (I do use 4 processors and 40GB; can try to increase it slightly) Because of the number of hydrogen bonding I find diffusion function necessary, though adding them to the reference method may demand much more time and computational resources in order to be calculated. How to bypass this problem? Maybe just use CCD/aug-cc-pVTZ? However, how long will it be calculating? Or just use optimized geometry from B3LYP/aug-cc-pVTZ level as a starting one, and then perform CCSD(T)/aug-cc-pVTZ with frequency and optimization calculations. The main problem arises from the technical features of the computer I'm using and time. What's is your opinion? Maybe use something completely different? Thank you.

Morpholine acetate is one of the ionic liquids I need to know about, but I couldn't find it. Is there anybody who can help me?

Dear Scholars I was wondering if anyone can recommend a publication on crude oil chemistry - particularly on SARA (Saturates, Aromatics, Resins, and Asphaltenes) classifications. Thanks.

I am working for PEM fuel cell cathode material. I am confused regarding the onset potential determination for my catalyst (CV attached, fig 1 is complete CV while fig 2 is its zoom image for clear understanding of change in reduction curve direction) and also why the reduction starts from 0.8e-4 A instead of 0 A. I performed this CV in calomel electrode under oxygen in 0.5M H2SO4. i) If I use Argon and overlap both the graphs then probably the curves start to separate at around 0.58V. ii) I have read in some discussions to consider the onset potential at which current density approaches 0.1mA/cm2 while in other discussion, I have read to consider 20microA/cm2 as onset potential. If I plot LSV curve for current density (instead of current) vs potential , then in first case (0.1mA/cm2), it would be 0.785V while in second case (20microA/cm2), it would be 0.775V iii) If I only consider the point from where curve starts to change the direction of reduction peak, it would be o.64V or 0.56V iv) if I draw tangents then this would be around 0.5V. So please help me in i) analyzing onset potential ii) guide me why there is positive current in the reduction peak iii) i also don't know what does the background correction mean and should I need to do it for my CV? All potentials are measured in SCE. So please help me to analyse onset potential in the best way and also guide me why there is positive current in the reduction peak. All potentials are measured in SCE.

In our field of research (chemistry), successful PhD research often requires a lot of experimental work in the laboratory. The completion of a PhD usually takes between 3 and 5 years. What's the duration of a PhD in your area?

As you know, a time crystal shows oscillations with a period longer than the driving force. Is it possible to use this feature in molecular machine synthesis? Does this provide any advantages to molecular machines?

So I have some pH = {4, 7, 10} standard buffer solutions from Fisher Scientific. But they must have went bad or I must have contaminated them because when I try to calibrate my pH meter to 4 using the pH 4 standard buffer solution, it calibrates the pH meter to 2 which obviously isn't right because it should be 4 so I can't trust the standard buffer solutions!!! I need to do some experiments which require that I accurately calibrate the pH meter which means I can't titrate the standard buffers with HCl or NaOH. I have to know the exact quantities. Might seem a little over-the-top, but I want to be really certain about the math. I intend to prepare my own calibration standards using exact quantities of chemicals. Total concentration should be 0.1 M, volume needs to be 100 mL. I think 0.1 M is a good choice because that should have low ionic strength and not much crazy debye-huckel variations in pH. I am pretty certain that I know how to prepare a pH = 4 standard buffer solution using acetic acid and sodium acetate. But I am not quite sure how to prepare a pH 7 standard. First of all, is this exactly how I should prepare a 0.1 M acetate buffer in 100 mL? According to pubchem the pKa of acetic acid is 4.76. I have a chem textbook which tells me that the pKa is 4.74. Not much difference so I will assume pubchem is right. HA + H2O --> A- + H3O+ Acetic Acid + H2O --> Acetate + H3O+ Henderson-Hasselbalch Equation: pH = pKa + log([A-] / [HA]) pH = pKa + log([Acetate] / [Acetic Acid]) = 4.76 + log([Acetate] / [Acetic Acid]) For the total concentration: [Acetic Acid] + [Acetate] = 0.1 M The simultaneous solution to these equations is about: [Acetic Acid] = 0.0852 M [Acetate] = 0.0148 M pH = 4.76 + log(0.0148 / 0.0852) = 3.9998 etc ... Pretty much exactly 4! I have glacial acetic acid and sodium acetate. Glacial Acetic acid is a pure liquid so its concentration is its density / (Formula Weight) [Glacial Acetic Acid] = [(1.05 g/mL) / (60.05 g/mole)] * (1000 mL / 1 L) = 17.5 M Basic Dilution Equation: Initial Volume = (0.0852 M / 17.5 M) * 100 mL = 0.487 mL glacial acetic acid in 100 mL total volume. Sodium Acetate --> Na+ (aq) + Acetate- (aq) grams sodium acetate = (0.0148 moles sodium acetate / L) * (82.03 grams sodium acetate / 1 mole sodium acetate) * (1L / 1000 mL) * 100 mL = 0.121 grams sodium acetate So I can exactly prepare a pH = 4 is 0.1 M acetate solution by adding 487 microliters of glacial acetic acid & 0.121 grams sodium acetate to 100 mL volumetric flask, and bring the volume up to 100 mL with ultrapure deionized water? Swirl to mix. ----------------------- I am confused about how to prepare an exactly pH = 7 phosphate buffer solution. I know the step wise dissociation of Phosphoric Acid. But the problem is that I am not certain about the second dissociation constant. H3PO4 --> H2PO4- (aq) + H+ (aq) H2PO4- (aq) --> HPO42- (aq) + H+ (aq) If I know the second dissociation constant of phosphoric acid I could figure out exactly how to make a pH = 7 standard 0.1 M phosphate buffer solution using phosphate salts. My undergrad general chem text book is telling me the second Ka is 6.2 * 10^(-8) or the pKa is 7.208 and pubchem is telling me the second the second pKa is 7.09. Thus I could use the Henderson-Hasselbalch Equation again with the total concentration to figure out the exact quantities. But I am not certain about what the second pKa of phosphoric acid is! Are undergrad chem textbooks just wrong? That's too much of a margin of error. pH = pKa + log[(K2HPO4) / (KH2PO4)] Also I was wondering if a 0.1 M solution of NaCl would have a pH of EXACTLY 7? Would it be more or less accurate than making the phosphate buffer? NaCl is formed by the titration of a strong acid HCl with a strong base NaOH. Therefore the equivalence point of the titration of a strong acid and strong base should yield a pH 7 of neutrality forming NaCl. So if I dissolved NaCl in water to yield a 0.1 M concentration would the pH be just as good as making that phosphate buffer solution? I also need to figure out how to make a pH = 10 standard buffer solution. Any advice? Can you make my life easier? Thanks so much!

We are planning to extract phosphorus from biochar by organic acids. If anyone has some procedure (concentration of organic acids & steps) please inform.

#COVID-19 Coronavirus Covid-19: Current Research. Open Access Publications Chemistry in Coronavirus Research: A Free to Read Collection from the American Chemical Society https://pubs.acs.org/page/vi/chemistry_coronavirus_research?utm_source=pubs_content_marketing&utm_medium=axial&utm_campaign=0120_JHS_coronavirus&ref=pubs_content_marketing

I have extracted Manganese dioxide from zinc-carbon battery in order to prepare Manganese fertilizer . but it never dissolve , Why ??

A biosafety level is the level of the biocontainment precautions required to isolate dangerous biological agents in an enclosed facility. The levels of containment range from the lowest biosafety level 1 to the highest at level 4. In the United States, the Centers for Disease Control and Prevention (CDC) have specified these levels. In the European Union, the same biosafety levels are defined in a directive. Sabanci University is following the same directive in accordance with Turkish biological safety regulation.

I recently read: "The perovskite solution for the solvent quenching method (MAPI) recipe was prepared by dissolving 553.2 mg PbI2 and and 181.23 mg MAI in 1 ml anhydrous DMF/DMSO (4:1, v:v) to obtain a 1:0.95 molar ratio solution (PbI2:MAI) with a concentration of 42.96 wt %." How can one get 553.2 mg of PbI2 and 181.23 of MAI (CH3NH3I) to be dissolved in 1 ml solution to obtain a 1:0.95 molar ration solution when the molar mass for PbI2 and MAI are 461.01 g/mol and 158.97 g/mol respectively. I am confused. Thanks for the help in advance.

I'm interested in reading about popular research being conducted in the organic chemistry world. Any ideas where to start? May we design intelligent reactions or intelligent reactant?

Some studies reveal that SARS-CoV-2 virus activity can be mitigated at the alkaline pH medium (above pH= 7.5). Any explanation about the mechanism or the Chemistry behind this phenomenon.

Cheers Everyone. I was seeing some uses of ionic exchange to recover NH4 by ionic exchange with other cations in a specific matrix. And it brought me to question what drives an ionic exchange to be better towards an ion in solution and not so good to another? I thought maybe the charge of the cation would influence but maybe is not so relevant as here Ammonium removal using ion exchange and biological regeneration K and Ca are ahead of Na and Mg. Maybe the hydration radius as an important role in it instead? And can pH of the solution where ionic exchange is done affect also the selectivity of the ionic exchange knowing it can affect the lattice charge of the matrix? Is there a way we can estimate this? or just by trial?

I need to download a chemistry book the original version in English and translated into Arabic that can help me , it is very importante

Dear crystallographers I have synthesized and crystallized a compound but after the XRD study i found out that the crystal structure of this compound already exists (the attached file A is my structure B is that of literature) but i noticed some differences : - My structure's volume is large by around 7.6 A - some minor difference in cell parameters. - Clear difference in R1 (mine is better). - Difference in number of asymmetric units Z'. My questions are: - Is my structure considered as a new structure ? - Can i publish it ? i have another structure (3rd one ) of the same compound but with a solvent inside the cell - Can i publish both structures (A and the 3rd structure ) in same article as new polymorphs ? ps: attached files: projection along the C axis of both structures with parameters Thank you in advance

In the age of Covid19, is there a basic conflict between science and superstition in the discipline of medical knowledge? Are there some simple, sensible, robust and reasonable ways to distinguish a scientific statement (or fact) from a superstitious statement? To stay focused, the topic will concentrate on science versus superstition in the scientific discipline of medicine. We will try our very best to stay focused and not stray off track. it is very easy to wander off message and be all over the map. i will try to summarize the key conclusions from time to time. In the age of the Corona Virus, there are so many statements out there. The statements may not be scientific. But if they are not scientific, are they false? Are they fake? Are they simply statements based on superstition. What should we do if people believe in statements that are not based on science? Should we be polite and tolerate their beliefs? As long as people do not harm others, then from society’s point of view, the fact that people hold non-scientific hypotheses is probably benign. However, the trouble starts when the same people act these beliefs, and then cause harm to others. The question arises: what should society do in this case? Based on the discussion, there are two assumptions and four categories. Assumption1: Beliefs cannot be justified or unjustified. Assumption2: hypotheses can be disproven Scientific hypotheses that are based on justified facts in natural causation. Or scientific hypotheses have not been disproven (I prefer the negative formulation because we may never be able to prove anything but we are unable to disprove it.) Since science cannot give a definitive answer, there are many competing answers that merit our attention, and we may not be able to select among them. Non-scientific hypotheses are unjustified facts that may be “proven” in the future with better evidence and facts. Pseudo-scientific hypotheses: not sure where these fit in? Superstitions are unjustified beliefs in supernatural causation.

chemistry is one of an interesting science in the world. but in most developing country student is nit prefer to learn chemistry. i mention the most two cases: in developing country mostly no laboratory accumulation, and there is no reference materials and so on.

When a piece of copper foil is placed in a test tube of iron(III) chloride solution? Fe goes from Fe3+ to Fe2+ and Cu2+ goes to Cu. Both are being reduced?

I come across many reactions like A + B --> products. How to consider "products" as a species and solve the kinetics in simulation/modelling, as such the reaction is unbalanced by logic of chemistry.

Any thoughts and recommendations on good articles, textbooks and resources on the topic of permanent magnet materials (e.g. neodymium) in terms of phenomena associated with their ageing and degradation under temperature, chemical, mechanical and electrical/electromagnetic stressing.

Hello everybody I want to simulate MXene by means of molecular dynamics method. But it seems that I need the Mxene atomic structure as a file in .cif, .pdb, or .mol format. Is it possible for anyone to tell me how I can get the files or how I can build the atomic structure of MXene? Thank you so much

Biological techniques are methods or procedures that are used to study living things. They include experimental and computational methods, approaches, protocols and tools for biological research.

At both very high and very low water activities, lipid oxidation rates are high compared to the rate at intermediate water activities. What can explain this trend?

Many efforts are spent to prevent, treat and stop COVID-19 spread. but I think these efforts are fragmentary and not organized. there is no platform for a scientific collaboration that could shorten the time of interesting findings, some nations hide some facts are a privilege of authorship or for other political reasons. I think that all countries should a global platform for scientific collaboration. Personally I have some ideas that could be proposed for the treatment of COVID-19 based on scientific facts but with the innovative mode of application, how and where can I try to apply them? All nations should avoid wasting their time to find a solution for COVID-19 without international collaboration.

How to deal with this problem? Example I have 10 sample, and I use duplo method. And we have a target for our sample's CV is under 5% In the 7th sample, the coefficient of variance is more than 5%, but it happened only in the 7th sample. In this case, another sample is fine (CV less than 3%). Do you have any idea what is going on?

The SARS-CoV-2 genome was rapidly sequenced by Chinese researchers. It is an RNA molecule of about 30,000 bases containing 15 genes, including the S gene which codes for a protein located on the surface of the viral envelope (for comparison, our genome is in the form of a double helix of DNA about 3 billion bases in size and contains about 30,000 genes). Comparative genomic analyses have shown that SARS-CoV-2 belongs to the group of Betacoronaviruses and that it is very close to SARS-CoV, responsible for an epidemic of acute pneumonia which appeared in November 2002 in the Chinese province of Guangdong and then spread to 29 countries in 2003. A total of 8,098 cases were recorded, including 774 deaths. It is known that bats of the genus Rhinolophus (potentially several cave species) were the reservoir of this virus and that a small carnivore, the palm civet (Paguma larvata), may have served as an intermediate host between bats and the first human cases. Since then, many Betacoronaviruses have been discovered, mainly in bats, but also in humans. For example, RaTG13, isolated from a bat of the species Rhinolophus affinis collected in China's Yunan Province, has recently been described as very similar to SARS-CoV-2, with genome sequences identical to 96 percent. These results indicate that bats, and in particular species of the genus Rhinolophus, constitute the reservoir of the SARS-CoV and SARS-CoV-2 viruses.

Hello, So I have conducted an experiment looking at the size of silica nanoparticles. However, the results I obtained showed that at a lower mass concentration of SiO2, the volume and radius of individual particles are greater than that of higher SiO2 mass concentration. I can't seem to find an explanation regarding this and was thinking that at lower mass concentration the individual particles colliding somehow caused them to agglomerate together causing the bigger particle size.

Dear researchers, I have some salt solution analysis. I want to know is there any software to estimate the scale deposition thickness in a specific time period on a metal plate at a known temperature (like a stainless steel heat exchanger) I want to predict the scaling thickness in evaporative and non-evaporative condition. Thanks.

Seems like a silly question but I'm having trouble with searching for CIF files via https://www.ccdc.cam.ac.uk. I've used it before but I was on university campus so I think I was able to use more than just the simple search function. I think I used structure search before and I was able to type in the compound name and the structural formula to get a CIF file, but now as I'm working from home, I don't have a CCDC licence and so I'm restricted to just the simple search. I've tried just typing in the compound name and no results come up. Will I need to search compound names with a paper that potentially has a CIF referenced? Or have I just misremembered how to use CCDC! Any and all help appreciated, thanks!

Column chromatography with Silica Gel columns with inbuilt UV detector. Compound structure is mainly poly unsaturated fatty acids and analogs without UV handles.

Assume a solution with acidic pH, which consists of 2 and 3 valent iron ions. With increasing the pH, iron content will precipitate. Do ferric and ferrous precipitate in an equal pH? If no, at what pH will precipitation happen for these ions?

Hello, I am looking an all solid state halogenide ion conductor (conducting halogenides, not necessarily based on them) especially iodide ions for a solid state battery. Poorly the research seems almost exclusively on monovalent cations like Na+/K+/Li+. Also the ion conductor should have approximately 10^3- 10^-2 S/Cm at room temperature. any ideas? thanks a lot

basically scholar is having maths and statistics background but he is doing research in fluid mechanics. he is interested but difficulty is finding problem and doing paper publications. so we need some suggestions. how to develop knowledge on this research area being a mathematics scholar.

Hi everybody! I am PhD in analytical chemistry and I make part of a multidisciplinary team working on the development of a web based solution focusing mainly on treatment and management of environmental chemistry data. But in order be more acertive in this project I need to interview researchers worldwide to trace a more realistic picture on how they deal with their environmental data. Could any of you please help me by giving me a 40 minute interview? We could make it via WhatsApp or Hangouts (or other choice). Messages in private to more details are welcome! Thank you all very much in advance. Yours sincerely Gilson

My lab has hydrazine sulphate. I need to convert it to hydrazine hydrate. How can I do this?

I want built a small biochemistry lab for research purpose ( Phytochemical Study). Phytochemical screening  It refers to the extraction, screening and identification of the medicinally active substances found in plants. Some of the bioactive substances that can be derived from plants are flavonoids, alkaloids, carotenoids, tannin, antioxidants and phenolic compounds. Please give me some guideline and references for built a small laboratory.

What are the oil based inputs for production of bio-polyamides for application in textile sector?

When comparing different Li-ion cells (no cooling) , what is the general trends in cycle life vs temperature? Across different Li-ion chemistries (NMC622, 532, NCA etc), is there a generic trend.

Hi everyone, I'm not able to find the correct citation style for Rubber Chemistry and Technology (ACS). I'm using the Endnote plug-in "Cite while you write" for Microsoft word. The references should be superscript, listed by appearance order and edited using first name, surname. Such as: R. B. Fox, RUBBER CHEM. TECHNOL. 68, 547 (1995). doi:10.5254/1.3538755 P. J. Nieuwenhuizen, J. M. van Veen, J. G. Haasnoot, and J. Reedijk, RUBBER CHEM. TECHNOL. 72, 27 (1999); 72, 43 (1999). The "ACS-no title" citation style seems to be ok, but in the list, the surname appears before the name (as usual) and it is wrong. Fox R. B., RUBBER CHEM. TECHNOL. 68, 547 (1995). doi:10.5254/1.3538755 Thanks for any advice, francesco valentini

We used the one step method in the lab to obtain FAME for our GC analysis. Many time we see varying degrees of evaporation of solvent (BF3 and internal standard) from our test tube during the 1 hour heating. We tried putting PTFE tape around the thread of the test tube but we have varying success rate. How would you effectively prevent evaporation of solvent in a screw-capped test tube during heating in a water bath? See here for the simplified method we used: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2593112/

Using DCM as a solvent for functionalizing a gold/silicon substrate with a self assembled monolayer by immersion. I noticed that after while, the solution is turning cloudy. Why does that happen?

I am doing a research project on "Chemistry and Cooking".

Hello! I am working with short-single walled carbon nanotubes dispersed in water. There is .3g in 30ml of water. I need concentrations of 10ug/ml, 20ug/ml, 30ug/ml, and 40ug/ml. I was told that since the CNTs are already dispersed that we basically need to take X amount of our stock solution and dilute it with X volume of water and we will have our desired concentrations. I am a horticulture major and this is my first venture into a project of this magnitude. I can't seem to find a chemist or bio professor to help me, can anybody help me out? Would really appreciate it.

We have a solution with an oxygen concentration of 6.5 ppm. How to Calculate Oxygen Pressure in a Solution Using Oxygen Concentration?

Ethyl Benzoate protonates with HCl to form protonated Ethyl Benzoate and Cl- (Screenshot Attached). After the Ethyl Benzoate is protonated with HCl(non aqueous) in a non aqueous solution, would the protonated Ethyl Benzoate then serve as a cation, and the solution's PH can then be measured by a standard electrode? Would the H ion pop back off of the oxygen in the presence of an electrode? Essentially I am looking for a way to measure the PH (or relative PH) of this non aqueous solution.

Adsorption is sub wed in science chemistry surfaces..it is two types : physical adsorption and chemical adsorption....eta

Alginate is an anionic polymer and on the other hand Rhodamine B is a cationic dye. Theoretically these two should be boned by ionic bond. Does it happen? More suggestions and experience are greatly appreciated. Advanced thanks!!

When weighing powder substances, static tend to cause unstable reading on an analytical balance, and most annoyingly, causing sample to stuck and disperse around the mouth of test tube. How do you overcome this problem? I know company like Shimadzu has a static remover block for this purpose, but it's too expensive to get one.

The HC gas upstream T,P is known and downstream P is know. A cooling effect is likely to occur since moving from a high pressure to low pressure across the control valve. One of the things I am not sure how to estimate is the Joule-Thomson coefficient.

This nomenclature has confused me for years, and I have been told different answers. Does 1:1 25 mM AmBic/50% ACN refer to A) a final concentration of 25 mM AmBic and 50% ACN, B) equal amounts of 25 mM AmBic and 50% ACN mixed (final 12.5 mM AmBic and 25% ACN) or C) something else entirely? If A, Then what do you do with recipes that call for 1:1 25 mM AmBic/ACN (implying 100% final concentration)? Thanks for the clarification!

1.Looking for easy comprehensive and authentic books on analytical chemistry I am already using G.D christian Harris Quantitative chemical analysis Skoog and west I just want to explore some book other than these! 2. Do tell me some good precise and easy to understand books on spectroscopy?

For example, which is more likely to oxidise to the equivalent phosphate, triethylphosphite or tris(2,2,2-trifluoroethyl)phosphite?

A plasma bonded PDMS device to glass slide when treated with pluronic, will make the surface hydrophobic? I know that pluronic is used to avoid deposition on surfaces, but what does it really do to make the surfaces deposition free.

I would like to start a project for the construction of rockets as a project for high school students. Starting with the development of a solid fuel (KNO3 + sugar) which is the safest method for the production? What additives can I use? I have seen from very simple elaborations, to more elaborate methods with the same components. Heat the mixture and manipulate it how dangerous it is? How do I estimate efficiency?

The unit of Tafel slopes are mV/decade (for cathodic and anodic slopes). What mean the decade?! is it (log scale) only ?!

I have performed a demethylation reaction using BBr3 and neutralized it with sodium bicarbonate solution and removed the water by lyophilization. Now, I want to separate my product from reaction mixture. My product is soluble in methanol and water. Could anybody help me to give idea for separation of the product?

What happens when HF and SiO2 react? Will other toxic / hazardous substances be created as a side product? Thanks!!

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.

I am removing carbonates from clay and sand samples. So, I treat the sediments with H2O2. I need to wash the sediments to remove acid residues. I am thinking of heating the sediments with ultra-pure water over hot plate and subsequent evaporation. The process can be repeated for 3-4 times over hot plate. Will it work and act as an alternative method of centrifuge washing?

Needed for review

See above

Dear Community, as i want to find out the impact of ceramide on my cells in DMEM-F12 medium. I dissolved C16-CER in Ethanol and added it to my medium. After having a look through the microscope, i see that it precipitates.  Does anyone have a solution for my problem? And do you know if C2-CER is easier to use? Thanks, Konstantin

Is anybody can help me to prpapre dual buffer system viz. Histidine-acetat, Histidine-phosphate, Histidine-citrate, arginine-acetat, Arginine-citrate How can we select a dual buffer for particular pH reasons behind that. In dual buffer how theory weak acid or weak base and its conjugate would work and chemistry behind if that

Whenever I pyrolyzed NaH2PO2, I am facing difficulties in cleaning the white left over residue (may be phosphates) in the tube. So, I am looking for any effective cleaning protocols to get rid of this issue. Thanks.

I am currently proposing a study about the formation of free PUFAs (EPA and DHA) in raw oysters treated with acidic sauces. Based on a study by Sajiki et al. (1994), free PUFA formation may be caused by the activation of lipolytic enzyme in the oysters treated with acetic acid. However, I am confused regarding this mechanism since the oysters are not alive. Can this explanation be used for dead oysters? Is there a better explanation for the formation of free PUFAs? Here is Sajiki's study if you are interested: Impact of Vinegar Acetic Acid on Hydrolysis and Oxidation of... Any answer or literature will be appreciated, thank you!

Hey all Technical papers or not Is there one search engine that embraces all the detailed procedures and guidlines for lab scale processes and synthesis methods

Branch of chemistry

As well known In almost all papers the experimental section is so short and not detailed for instance no clear weights setup and so on Where can we find expanded detailed narration of experiments and methods

While I am looking for academic positions in Canada, they are constantly asking for a research proposal in NSERC format. I never had an experience of making a proposal in that format. Hence, I am requesting the research community here in to share their proposals. If you want to share with me only, please send it as a message. I will keep it confidential. Any sample of proposal (awarded/non-awarded) in that format will be great help for me to fasten up and amend my proposal. I am very much grateful if someone can share their sample proposals.

Hello, I will soon start a new project in which electrochemistry is applied in organic chemistry. It will be totally new for me and for the group where I work. Do you have some tricks or advise for this topic? Thank you very much

Journal, Magazines and Letters publish scientific articles. What is technical difference between these articles and their recognition? Writing Style, technical soundness, number of words etc.

A resazurin-based assay was produced with ampicillin against E.coli , negative control was just LB media and E.coli and the positive being ampicillin and E.coli, with resazurin for the readings. Plate readings were taken initially and then every 30 minutes for 2 hours. The only data I have is the plate readings and the initial concentration of ampicillin added. How would I work out the final concentration of ampicillin?

I want to mix Graphdiyne into NDP-V that is non-fullerene polymer and seldom used as electron transport layer. could you please predict its chemical properties or kindly send some research articles of someone already did it. Thanks in Advance

Dear colleagues, At the brink of curricular reform in Czechia, we stand before the question how, if ever, to exit the traditional structure of lower-secondary chemistry curriculum. We found several resources describing such initiatives, but so far nothing we could use to support our ideas during the talks with the policy-makers. Could you please refer us to some resources? Thank you in advance. Best, Martin

I was once told that stable isotopes of lighter elements such as H, N C , etc are found in stars, planets, etc. Can anyone suggest any literature which talks about the formation of these isotopes?

Hello sir I am looking for a collaboration working for a synthesis project in organic chemistry. Regards

I am using 1g/L stock solution of Copper and Zinc prepared from Copper Sulphate pentahydrate and Zinc Chloride, respectively. I am using the stock solution to prepare standard solutions of concentrations between 0.1 mg/L to 10 mg/L by dilution. I am preparing the standard solutions everyday by dilution from the stock solution to calibrate the Atomic Absorption Spectrophotometer. My question is that is it OK if I store the standard solutions, which are of quite low concentration and use them for future use instead of preparing everyday from the stock solution? If yes, what is the maximum storage period for which I can use them?

Yesterday on December 5th, 2019 at 3:45 p. m. a full bottle of our homemade brandy on the small kitchen table on our kitchen spontaneously exploded. I am a retired university professor in chemistry and very knowledgeable in physics but I do not understand how could it happen?

I have been looking into MSDS of KOH of 0.1 M, and it says use proper ventilation area while working. But in my lab, we don't have fume hood to work with. And I am not able to find any safety sheet on 0.001 M KOH solution. I would also like to know about any possible health effects of this.

I need to find a proper method to prepare sample solution by digestion for Pt-Pd-Rh elements from spent automotive catalysts. Any suggestion except application of microwave-assisted digestion would help me.

hello every one I want to synthesis the CuInSexS2-x QDs and as I am elementary in chemistry, I want to know that how to determine the sub x in such structure in practice (mean in the synthesis of CuInSexS2-x QDs in Lab) ? and could you introduce me a source for more study about this fundamental issue in chemistry? thanks

Good evening. I am working on my bachelor’s thesis and i need some informations about water solubility of Drotaverine HCl. I couldn’t find something usefull not even on chemistry websites. Thank you for your help !

Do there exist any compounds, fluorophores, dyes, quantum dots, phosphors etc that can emit or fluoresce non-linearly without needing ultra-high intensity illumination (such as pulsed femtosecond laser)? That is, with a UV led for example and with this non-linear emission being dominant?

Hi all, working on a task where HF acid gas may be present due to Li-ion battery combustion (faulty batteries, over-changing, transport/vibration) in a container. Curious how one would design a filter or neutralize this gas in order to lessen damage to humans and surroundings? I imagine this may be a chemical engineering question, which I have no experience with. Thank you!