- Pardeep kumar Gianchandani asked a question:NewHow can I calculate the amount of Un-reacted element?
in my research activity i am using two (Mo and Si) elements and treat them at high temperature more than 1350 C and after that i want to quantitatively analyze reacted elements such how much Si and Mo remain in reaction site and how much in quantity they have different phases.
- Michael David Higham added an answer:3Is there any database available for the band gap of d block elements?
Can anyone provide any link or complete database about the band gaps of pure d block elements from Sc to Zn. Thanks in advance.
thanks for clarifying your problem. I'm still not sure what you mean when you suggest that the different metals would not be equally metallic. To me, something is metallic, or it isn't, depending on whether it does or does not have a density of states at the Fermi level (the exception to this being Mott-Hubbard insulators, where inter-electron repulsions in materials with a narrow, partially-filled highest energy band cause this deviation from "normal" behaviour predicted by standard band theory). Do you mean that different metals might exhibit different electrical properties, such as electrical conductivity, that we associate with metallic behaviour?
I am not and expert on clusters, but I agree that it could certainly be possible for clusters to exhibit an electronic structure that is markedly different from their bulk metal counterparts. However, I am not convinced that there would be a bulk quantity that would directly correspond with band gaps that you may have observed for metal clusters. Perhaps simply considering the band-gap for your clusters as a function of the proportion of d-band filling in the bulk metal would be an option. As far as I can see, this is the main difference between the bulk metals you are considering (some have more or less of their d-band filled than others), so if you do observe a trend in your band-gaps, perhaps this could be related.
Anyway, I wish you all the best with your research, I hope my comments have been helpful. Feel free to respond if there is anything that I have said that is unclear.Following
- Galal Hamed Habaak added an answer:7Where do i purchase International Rock standards like BCR, PAAS, or Japanese Basalt for calibrating XRF machine?
I want to do elemental analysis of the Mesozoic shales and siltstones and wanted to standardize the XRF instrument, could any one suggest from where i can purchase rock standards?
I am from Egypt and after about 30 years experience in geochemical analyses I found that the best standards are the Japanese standards and can you use the following web:
- John Bratton added an answer:4I’m planning to investigate Al and Si co-deposition in silicophytoliths. Can anyone send me information about this subject?
I am especially interested on papers about elemental anlaysis of silicophytoliths
You may want to contact Wendy Zellner at USDA-ARS Toledo.
- Douglas Kitt added an answer:3How can the amount/duration of oxidation/activation be known which is done on the Activated Carbon?
1. What kind of elemental analysis should be done? C,H,N %? I tried contacting labs for finding the amount of carboxyl groups, but i didn't get an appropriate answer! If you have any laboratories to suggest which carry out such tests, it would be of great help.
2. I was advised to go for Raman Spectroscopy by one of the labs, which will measure the grain size of the sp2 bonded carbon, the larger the grain size, the less active the carbon would be and vice versa.
3. What would be the best possible way to know the amount of oxidation carried out on the activated carbon? Also, I carried out the moisture tests and the AC which has more n-Butane adsorption capacity is less hydrophilic than the normal one.
4. I carried out sieve analysis for particle size distribution, for the AC with good n-butane adsorption capacity; the range 200-315nm covers 13% of the whole sample, while in the normal one it is only 8%.(See Attachment)
5. The n-butane adsorption capacity is measured under an adsorption test bench for bulk density. The sample(7g) is heated at 150 C and conditioned; later
on it is tapped for 900 cycles. Then the n-butane gas is passed through
the sample at 80ppm concentration with a volumetric airflow of 60 l/min and a breakthrough graph can be obtained. Also, the details for the total adsorbed quantity can be known at the end of the test. In the attachment, you will find a breakthrough graph for Type-1&2; where Type-1 is normal AC and Type-2 is the carbon with high n-butane adsorption capacity.
4. In the attachments, you will find the reports for sieve analysis, N2 isotherms, Micropore volume, Total pore volume, Pore size distribution.
PS.: Type 1&2 are produced by Rotary Kiln, Type 3 is produced by Fluidized bed Reactor and hence Type1-2 and Type 3 has significant physical differences. The mentioned type of Activated carbons are made out of coconut shells.
I thank you in advance for your valuable suggestions and time.
What are the effective methods of differentiating two kinds of 'Activated Carbon'? - ResearchGate. Available from: https://www.researchgate.net/post/What_are_the_effective_methods_of_differentiating_two_kinds_of_Activated_Carbon#55e6f2bd5f7f715cf28b45d3 [accessed Sep 2, 2015].
I have a related question, forgive the intrusion, but it appears there may be someone here who knows the answer to a question I posted elsewhere.
- Lingshan Ma added an answer:4What is the definition of "degree of sulfonation" and how can I calculate the theoretical degree of sulfonation?
Hi, I am making membrane using sulfonated polyethersulfone (sPES). A higher degree of sulfonation(DS) of the PES is needed. But I want to know how to calculate the theoretical DS as well as the definition of it. Also, I had different results when test the DS by polymer and by membrane. Which one should be the correct one? In addition, I sometimes get turbid solution during the titration (milk-like). What maybe the reason of it? Thank you very much for your time!
Thanks Eftychia. It is more much more clear! So basically I need to calculate the mol of sulfonation agent I want to add, and the mol of the polymers I want to add. Then divide n(agent) by n(PES)? But do you calculate the theoretical DS before sulfonation? Or just use experience and according to paper? As for the difference of DS between membrane and polymer, could you provide me more information like what do we prefer to see from the DS of membrane/polymer if you have time. Many thanks for your time!Following
- Christelle Bonnefoy added an answer:3How do I deproteinize serum and semen samples for metal analysis using ICP?
I have serum and semen samples, i want to prepare it for elements analysis by ICP technique, I need to know how to deproteinize samples?
- Mohammed El Amine Benamar added an answer:6Does anyone know about comparative analysis of elemental composition of various wheat varieties (seeds)?
I have seeds (limited supply, with less than a gram for some varieties) as the starting material. Please suggest a suitable platform / machine, sample preparation methodology and analyses. Thanks.
you can see the link below
- Jean Aimé Mbey added an answer:11In case of deposited film on any electrode (say graphite), what might be the reasons for not getting any characteristic peaks from Powdr XRD analysis?
I am getting only the subtrate (electrode) peaks and not the electrodeposited samples peaks although i can see visually the smooth deposition of Ni and Ni(OH)2 onto it. I wonder what are the possibilities of not getting any PXRD peaks although EDAX and other elemental analysis prove its presence. The thickness of the deposition is about ~ 5-6 micrometers (from AFM and SEM cross sectional image).
Please suggest what might be the case.
Dear Manjeet Chhetr, to check if your product cristallinity, you just have to registered the XRD pattern of the compound alone. To do so, you need an amorphous carrier for your sample. In case the sample is cristallized, then you will observed the product diffraction peaks. The peaks intensities and positions on the pattern may be useful to understand wether, when deposited on graphite, the peaks overlap graphite peaks or not.Following
- Xiaowei Zhou asked a question:OpenHow do I created Hexahedral elements from pyformex for abaqus/cfd?
I used the similar method as this video(https://www.youtube.com/watch?v=T1pVFCzrmGI) in pyformex(www.pyFormex.org) to generate the hexahedral elements for my vascular cfd in abaqus. The meshes were very well(very good 8 nodes 3d bricks). Then I exported the meshes to a .inp file with the nodes and elements information. In the .inp file, I set the element type as FC3D8 manually. After that I can import the .inp file in Abaqus/CAE with file-->import-->model. Then I got the orphan mesh in Abaqus/CAE. Everything goes well at this point. But when I use the mesh verify in abaqus/cae to check the meshes. It shows 100% elements with analysis errors.
I tried to create a job with these meshes and run it. But there was one error popping out, saying "Quadrature Errors in Pressure Poisson Equation - Element(s) severely distorted. Possible diagnostics are: (A) Check the quality of the elements in the mesh to see if they confirm to the element type specified. It is possible that certain elements are interpenetrating or have become degenerate during the mesh generation. "
I doubt the meshes generated from Pyformex are not compatible with the FC3D8 element type. However, the elements I can see from pyformex are quite well(very nice 8 nodes brick). And the group who developed the pyformex also used abaqus/cfd to do their simulation based on the meshes generated from pyformex.
I really don't know the reason. If anybody can give me some clues on this issue, I will be very grateful.
PS. I attached the .inp file and the pictures of the meshes below.
- Miroslava Sýkorová added an answer:7How do I perform elemental analysis in metal bhasmas of Ayurveda?
Atomic absorption spectrometry is used commonly for elemental analysis.Some tests have to be conducted for this where the results are repititive like particle size,molecular structure etc.Which minimal tests have to be conducted which can give maximum results.
X- ray spectrometry is a good technique for multielemental analysis plants and pharmaceuticals. You can use x-ray spectrometry with x-ray tube or radionuclide source.Following
- Anjana Acharya added an answer:1What elements should be used in mesh module for shell analysis subjected to bending in ABAQUS?
While I am doing a simple shell analysis subjected to bending using linear elements in ABAQUS, the analysis completed without any errors. But while I use quadratic elements, the analysis aborted. I have heard that for bending analysis of shell elements, quadratic elements should be used. But then why the analysis aborted? Meanwhile, I have used static general steps for my analysis.
Palladium can be used for the quadratic purposeFollowing
- Vladimir Dusevich added an answer:3How can I subtract background from EDS elemental analysis readings?
I had my sample tested with EDS elemental analysis. The person in charge of the instrument told me that the results included background which was copper grid and carbon film on the copper grid; I was given the readings of background only as well. However, I am not sure how to subtract background from the sample readings, i.e. to derive the results of just my sample without background values. The two readings are in the file attached with this question. I would be really appreciated of your kind help. Thank you very much in advance.
It is not a background, but spectrum of support film and from stray radiation in TEM. There is no easy way to subtract this "background" . You cannot quantify your current data. The only thing that is obvious from your tables is that Ca, P and O are present in your specimen. You can say nothing about C, Si, Cr, Cu even if some of them are present in your specimen. All other elements are suspicious: you need to verify that their peaks are really present, that they are statistically significant (quantification software is prone to erroneous "identification" of non-present elements)Following
- Laith Najam added an answer:2Is Black Carbon detected by a CNS elemental analyzer?
Does the thermal stability of Black (Pyrogenic) Carbon affect the detection by standard CNS Elemental Analysis? As it is stated that this method detects Total Organic Carbon, Black Carbon should be detected asweil.
yes , Black Carbon can be analyzed by CNS elemental analyzerFollowing
- Marcial Yam added an answer:5How do you calculate the degree of sulfonation for polymers using CHNS analysis?
Can anyone tell me what the formula is to calculate the degree of sulfonation for poly(bis phenoxy)phosphozene from CHNS analysis?
You can calculate with the IEC formula is more direct if you want to calculate with a titration method, or could by NMR only you need to know structure, positions of the sulfonic groups.
wmolecularxMolarConc NaOHxVolume comsumption of NaOH/wsamplex1000-wofsulfonicgroupxMolarConc NaOHxVolume comsumption of NaOH
and thats it.Following
- Maarten A.T.M. Broekmans added an answer:20Is it natural to have Sulphur in Garnet?
I have been observing a metamorphic rock that contain Almandine garnet using SEM-EDS. The presence of garnets is confirmed by the very rock's XRD patterns (both Pyrope and Almandine are present).
Element analysis (SEM-EDS) of various points on Almandine/pyrope shows the following general chemical composition in wt%
Na - 0 - 1% K - 0 - 1 % Al - 17-19%
Mg - 4 -7 % Si - 25 - 30%
Ca - 4 -1 % (Total)Fe - 30 - 35 %
Strangely, Sulphur is there ranging 0 to 2%
Is it natural to have Sulphur in garnet? and are Na, K, Mg and Ca inter exchanging with each other?
Additional Info (XRF analysis (FP method) shows S element about 1.6 wt%. but XRD does not show any peak for possible Sulphur bearing minerals such as pyrite or gypsum. Still the rock samples have strong sulphur smell).
Thank you in advance
Thanks for your reply.
I am not surprised that you don't find any pyrite or gypsum by XRD: the amount of pyrite needed to give off a detectable S-signal in microanalysis is MUCH smaller than your XRD lower limit of detection LLD, which is on the order of 1-5wt%, much depending on sample (notably the type of comminution) and specimen preparation of bulk rock powder, as well as its mineral content. (In fact, modal analysis of bulk powder or powdered rock including trace minerals by XRD can be challenging; eg. check literature on Reynold's Cup!)
Really, by far the most practical method to verify the presence of pyrite inclusions in garnet is optical microscopy, in transmitted light where they will appear opaque, as well as in incident illumination (as suggested by Greg Raab) where they will appear as bright spots if at the surface. Thin- and/or polished-section petrography will also reveal any other S-containing minerals present, which must show up if you report 1.6wt% S by XRF, or alternatively ~4wt% SO3.
To conclude, I confer with Giovanni Ferraris: chemical analysis alone is INsufficient to determine mineralogy. Imagine you are analyzing carbonate by EPMA and find 56wt% CaO (a very good analysis, even when far short of 100wt%), how would you know whether this would be calcite or aragonite (or vaterite)? The simple answer is: by thin-section petrography, which through optical properties provides information on which polymorph you are looking at.
- Yafei Wang added an answer:11Does grinding and polishing influence the detection of elements under EDX?
EDX is used to determine the elements on sample surface, combined with the observation under SEM. For metals, they are usually grinded or polished before observation. However the preparation process such as grinding by abraisive paper will contaminate the specimen. Accordingly, unexpected elements from abraisive paper such as Si and C could be detected through EDX, which has a bad influence on the results.
You have proposed a very good point in your answer about the inteference of the polishing materials and the elements we are interested in. In other words, choosing the right polishing materials may solve the problem, of course, when there is an option.
- Marcial Yam added an answer:5How do I prepare serum samples for the simultaneous determination of heavy metals using AAS?
Want to perform elemental analysis of blood serum samples but not getting an easy one step method for sample preparation. References provided will be highly appreciated.
Well I told you, that you need consult methods of digestion dry or wet depending of the extracción, if you use microwave you can use 0.5 g of sample dilued in 25 ml of nitic acid, so you can check any book of standart methods of analysis to ensure he right quantity of nitric acidFollowing
- Patrick J. Sharrock added an answer:10How can I calculate elemental weight percent from oxide weight percent given by XRF?
Hi everyone..I'm running elemental analysis using XRF for carbonated hydroxypatite. I want to find the elemental value of Ca and P. As we know XRF give the analysis in the oxide such e.g CaO . How to obtained the Ca weight percent from the CaO given by the XRF?
If your EDX machine is working properly, and the operator knows what he is doing, then the elements are listed as % oxides, and can be shown to add up to 100% or not, depending on the particular analysis. However, some elements could be present for example as sulfates of sulfides, or simply not oxides, so a clear image can be obtained if all elements are analyzed and unravelled to give the total elements, and even then, porous products will not add up to 100%, so it can be said that EDX is only a qualitative analysis, chemical analysis is better for getting chemical results that are reliable, and real (EDX could give the result for surface hydrates or hydroxides, that do not reflect the inside composition of any sample). the instruments are also programmed to give you the elements as percentages directly, so you do not have to worry about converting oxides to elements if that is a problem for you......Following
- Rina Singh added an answer:5What are the techniques / methods to identify metal oxides in a mixture?
I am working on the catalysts that contain different metal oxides. I want to identify the metal oxides.
XPS and FTIR can be used to identify metal oxides.Following
- Jinbo Fei added an answer:1How can I find the type of oxides present and their percentage based on EDX elemental analysis of a surface?
Element- Weight%- Atomic%
C - 8.77- 22.56
O - 15.60- 30.13
Al - 6.70- 7.67
Si - 2.18 -2.40
P - 0.32- 0.32
S - 0.41 -0.40
Fe - 66.02- 36.53
Possibly, XPS is the better way to get the precise answer.Following
- Vivek Kumar added an answer:16What are the rules of measuring mass elements in composition?
I want to find the percentage of each elements in my thin film, the composition in my thin film is a mix of Al-Cu-Fe. I know, I can measuring by ICP-MS or XRF. but I have two question:
1st: Is the percentage for each elements different before and after annealing (temperature is around 800'c) or not?
2nd: Do you know another methods for measuring the percentages or volumes for each elements (the max error for my composition is less than 0.1% )?
can anyone provide me the protocol for ICP-MS to quantify the metalloprotein from given sampleFollowing
- Julie Perreault added an answer:8What is the best method for dissolving rocks for ICP-MS?
I need a clear method to dissolve variable rocks to determine elements (main and rare) by ICP-MS System.
could you help me to get this method in clear steps
thank you very much
By grinding your rock, you can perform an alkaline fusion into lithium metaborate 98.5%/ lithium bromide 1.5% flux. We already use this technic on geological sample for rare element.
0.1g of grind powder in 1g of flux. Perform the fusion into platinum crucible with a fluxer (Claisse Corp.) and recolt it into PFA beaker with 100ml of acid. (10%HNO3/0.5%HCL)
We dilute 60 times to reduce the salt into the ICP-MS.Following
- Le Zhang added an answer:2Can someone help me with trace element measurement by SIMS?
Recently, I used Cameca 1280HR to measure trace elements in basaltic glasses. The accuracy of most elements were +/-1-30%. However, Lu, Hf, Ta and Th (the contents of these elements are about 0.5-5 ppm) had poor accuracy (about 50% or even worse). The peaks of 180Hf and 181Ta were not good and it seemed there were some interferences (maybe 164Dy16O and 165Ho16O). But I don't know how to correct these interferences. The peaks of 175Lu and 232Th were normal. The interferences may be exactly overlaping Lu and 232Th. Could someone give me some advice to improve the accuracy? Thank you very much.
Hi, Zou, thank you for your information.Following
- Bendiba Guedouar added an answer:3What can WDS-SEM provide in addition to elemental analysis that is available in EDS-SEM?
EDS: Energy Dispersive Spectroscopy
WDS: Wavelength Dispersive Spectroscopy using SEM
- WDS is second flight especially if you have overlapping peak between Elements
then in this case the WDS makes distiction
- WDS is as precise as EDSFollowing
- Simone Cagno added an answer:8How reliable is energy dispersive X-ray spectroscopy (EDS) for elemental analysis of powder sample?
Is EDS sufficient to confirm the elemental composition of powder samples (composite) or is it necessary to go for advanced techniques like X-ray fluorescence (XRF) or XPS.
You could also think of using XRD to identify the mineral/crystalline phases present in your powderFollowing
- Matthew Wheal added an answer:4Can anyone recommend a standard reference material to use when measuring the total P and Ca in fish tissue using ICP?
Our goal is to compare whole-body Ca:P ratios between juvenile suckers with deformed opercula and without the deformity and between fish from two Oregon Lakes. I would like to know if deformed opercula that is observed on juvenile suckers and not on other species in UKL is likely to be caused by an imbalance in Ca:P. I would also like to know if the reason that the deformity doesn't occur in Clear Lake is due to a difference in the whole-body Ca:P.
Summary of methods: 1) Grind fish in a stainless steel blender (done), 2) ash fish blended fish at 550 C for 16 h, 3) weigh ash, 4) digest ash with HCl and/or HNO3 , 5) dilute with DI water to concentrations within limitation of instrumentation, and 5) use ICP to measure Ca and P.
I am having a hard time finding a standard reference material of measuring P in animal tissue. I know these measurements are done but no one reports what standards they used. I could use suggestions. Thank you for your help.
LGC standards list 24 fish materials on their website.Following
- Santosh Kumar added an answer:9How should one treat data with <LOQ values during statistcal analysis?
I have some data in which a number of the analyte concentrations (data points) obtained were below the quantitation limit (LOQ) of the method used. This is possibly as a result of both the low values of the analytes of intrest expected in the test samples and the method and instrument detection limits. In such a case, how are these "missing" data points treated during statistical analysis and subsequent interpretation and representation?
In Statistical Analysis, If the data is not in our desired way, We have to apply the data preprocessing techniques to form appropriate data.
Apply different different preprocessing methods and then analyse them. It will be a better approac and I think It will be very Helpful to You.Following
About Elemental Analysis
Elemental analysis is a process where a sample of some material (e.g., soil, waste or drinking water, bodily fluids, minerals, chemical compounds) is analyzed for its elemental and sometimes isotopic composition. Elemental analysis can be qualitative (determining what elements are present), and it can be quantitative (determining how much of each are present). Elemental analysis falls within the ambit of analytical chemistry, the set of instruments involved in deciphering the chemical nature of our world.