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  • Erkan Ilik added an answer in Cold Plasma:
    How can I calculate rotational and vibrational temperature of plasma phase?

    I am studying on cold flowing post-discharge plasmas at low pressure.  I use optical emission spectrometer for giving results about emission spectrums of non-local thermodynamical equilibrium plasmas. I want to calculate electron temperature of discharge and the post-discharge plasmas.

    Erkan Ilik · Eskisehir Osmangazi University

    Thank you for your help. I run this program but I coundn't understand the terms of"Slit Function". Would you give me about it in detail please?

  • How can I ensure a homogeneous mixture in a host:guest system based EML for OLED applications?

    I'm producing a blend of organic materials for organic light emitting diodes but I'm having problems securing the homogeneous mixture since the dopants' concentrations are too small. What are the the reported methodologies applied to secure this homogeneity (for example 99% Host and 1% Guest)?

    Daniel Pereira · University of Aveiro

    Because the concentrations of my dies are small, if I dissolve my mixture and then evaporate the solvent (I'm using thermal evaporation for the process) I will have all my mixture attached to the recipient. This is why I'm trying to find an alternative way.

  • Georg Matuschek added an answer in Alkanes:
    Can anyone suggest on GC method development and column to separate compunds like heptane, dodecane, heptadecane, octadecane and fatty acids ?

    Its about conversion of compounds like stearic acid, oelic acid using hydrotreating catalysts to get C5-18 alkanes. I need to find a suitable column and develop a GC method for this application.


    Georg Matuschek · Helmholtz Zentrum München


    we are analyzing organic components from urban aerosols by GC-MS with thermal extraction. Among the organic compounds are alkanes as well as fatty acids. We run the analysis on a VF-Xms 30m x 0.25 (0.25) colum from Agilent Technologies which works very well for our application. If you have liqid samples to inject, you can get this colum with an integrated 5m EZ-Guard precolumn for recondensing/refocussing.

  • Hopewell Molefe added an answer in Water Treatment:
    What are the advantages of using organic coagulants instead of Inorganic like Ferric Chloride and Aluminium Sulphate?

    I treat about 20 000 L of effluent before discharge aiming to correct the pH, Conductivity, reduce sulphates and chlorides to below 1500 mg/l. Reducing the COD as well to levels below 5000 mg/l. I have been achieving good results with ferric chloride as coagulant and reducing the sulphates, suspended & dissolved solids using lime. 

    I'm just interested in knowing the advantages of using organic coagulants, I do all my preliminary tests in the lab (jar tests) and in my pilot plant on site (treating 1000 L of influent).

    Hopewell Molefe · Omnia, Protea Chemicals

    Ok thank you very much, yea FeCL3 works very well for me currently. However I will try a number of the organic coagulants and look at using both FeCl3 and others.

    But I must say it's working quiet well with the lime treatment, I have managed to reduce sulphates (obtaining more than 75% reduction), reducing the COD by 72%, TSS from above 1100 FAU down to 28 FAU.

  • What is the best way to extract lignin and hemicellulose from a raw sample in preparation of cellulose nanofibers?

    What is the best way to extract lignin and hemicellulose from a raw sample in preparation of cellulose nanofibers?

    Mustafa Çiçekler · Kahramanmaras Sutcu Imam University

    There are two methods which are TAPPI methods.

    Firstly, You need to make extraction (for tannin, wax colour materials so on.)

    Secondly, Holocellulose must be obtained from this samples (Extracted samples). After obtain the holocellulose you need to determine alpha-cellulose content (Alpha cellulose is assumed pure cellulose).

    Thirdly, With H2SO4 you can obtain klason lignin.

    You can find these all methods on TAPPI website.

  • Sachin Rathi asked a question in Solidification:
    Plz anybody tell me about the LVDT process during casting in aluminium alloys during solidification?

    i need to find out the develope strees  during the solidification in casting process when load is applied at the same time.

  • Sanjay Paneliya asked a question in P Value:
    How to calculate adjusted p value in dunnett test ?

    Dear All,

    Please help me to solve below mention equation for dunnett test.

    I know how calculate q as per below mention formula.

    q= Mean1-Mean2 / SEDifference

    But I could not understand how to calculate adjusted p value as per below mention formula.

    pValue(adjusted) = PFromQDunnett(q,DF,M).

    Please provide example if possible or reference for the same.


  • How might I prepare a meat sample for FTIR spectrometer ?

    I was trying to use FTIR spectrometer to detect histamine in spoiled meat but i don't have any idea on how to prepare a sample. I am also confused if i should use a liquid sample or solid. 

    Franziska Schulte · art photonics GmbH

    It depends on which FTIR spectrometer you have and which accessories. It is pretty easy if you have ATR accessory. Just prepare fine slices and press it onto the crystal.

    Good luck.

  • Sushanta Sahu added an answer in CNC:
    What are the pinouts of this port on Alpha laser CNC table ALT200?

    I am using an ALT200 CNC table from alpha laser. This machine has an option for a CNC controlled rotary chuck. There is a port for it on the table, but order was not placed for the rotary chuck.

    Now that I want to interface a motor to it, some information on the port pinout is needed. If I insert the probes of a multimeter, voltage changes, but it reaches to almost 240 volts DC(it is an autoranging multimeter).

    It would also suffice, if someone has the chuck and is ready to share the technical details of the attachment. It should look something like the figure at the bottom.

    Can anybody identify the port, or its details?

    Sushanta Sahu · National Institute of Technology Rourkela

    Thank you Zol Bahri,

    Ushashri had worked in my lab with the machine I had shown above. And M Masanta is a professor in my Department. Your suggestion of (cX HERE) are not clear. I could not find any link. Also Prof. Masanta does not have a clue about this port. The Laser welding machine is with my lab, and Prof. Masanta is in a nearby lab.

  • How do you treat substance-induced psychoses?
    Few studies have examined the course of substance-induced psychoses after its acute manifestation. Substance-induced psychotic disorders predict schizophrenia spectrum disorders to a greater extent than previously thought http://www.ncbi.nlm.nih.gov/pubmed/23419236. I wonder if there exist differences between prognosis of Substance-induced psychoses according to the treatment used.
    Virginia Fuentes-Leonarte · Primary Care, Hospital Doctor Pesset.

    Thank you, Lindsey!

  • Olusegun Abass added an answer in Charcoal:
    Can one use the wooden source charcoal without activation for adsorbing the nutrients contained in the waste-water ?

    Can one use the wooden source charcoal without activation for adsorbing the nutrients contained in the waste-water?

    Olusegun Abass · Chinese Academy of Sciences

    @Samir, depending on the wastewater characteristics and nutrients present, activated charcoal cannot not absorb all nutrients (e.g Na, Nitrate), and as with all absorbents, they all need to be regenerated and dosed at high concentration to perform more efficiently. Therefore, using raw charcoal also does not guarantee the removal of all nutrients,giving the content of the wastewater.

    Hope this helps.

  • Shigui Qi added an answer in LDPC:
    How can I calculate the minimal distance of LDPC code?

    i have to calculate the minimal distance of a finite length LDPC code to compare it performance with other codes.

    Shigui Qi · Huazhong University of Science and Technology

    Dear Wassila Belferdi,

       If you get the parity-check matrix H of LDPC, the column weight of H adds 1 is the minimum distance of LDPC.

    Good luck


  • Peter Čižnar added an answer in Cryoglobulins:
    Can we consider a finding of cryoglobulin in any any clinical setting as an indication for real pathology?

    The concentration  limits and cryoglobulin nature whether mono or polyclonal as well as chronic condition of the disease.

    Peter Čižnar · Comenius University in Bratislava

    We had recently a case of 14 year old girl with 3 month history of persistent spiking fevers with shiverings and migrating large joints artralgias. We noted a 2 remissions while on bed-rest for couple of days. A broad diffrential testing was nonconclusive, but high cryoglobulin leves and increased inflammatory markers (CRP, SAA) were found. We have considered it clinically significant, though we were not able confirm the etiology.

  • Does anyone know about isaria fumosorosea (entomopathogenic fungus)?

    Can anyone point me in the direction of a good resource (book, paper, website) on culturing techniques for Isaria fumosorosea (entomopathogenic fungus) under lab conditions?

    Ana-Cristina Fătu · Institute of Plant Protection Research and Development



  • Satish Kumar added an answer in Cysteamine:
    How can I couple my gold nanoparticle with cysteamine solution? and transferrin protein onto it?

    Helllo everyone

    I prepared a cysteamine dispersed in ethanol solution but it precipitated, not completely dissolved, but I used it for my concentrated 1 mL of gold nanoparticle solution, colour was changed and the peak of gold nanoparticle (521 nm) was shifted to 559 nm, as I see in UV-vis I thought that CYS coupled my gold nanoparticles but I went to zeta meausement and as a result of my zeta potential I saw -18 mV, meaning not coupled, I need a proper protocol, I would be so much glad if anyone can suggest me.

    The other problem of mine, I need to cover my cys coupled gold nanoparticle with transferrin protein, but I need to put olıgonucleotide as well onto the nanoparticle, which one should be previous step?

    Thanks in advance

    Satish Kumar · Indian Veterinary Research Institute

    you need to follow steps 4,5 and six after cysteamine-AuNP preparation

  • Umar Yusuf Madaki added an answer in SAS:
    How to perform Barnard's unconditional exact test in SAS?

    Dear SAS users,

    I want to perform Barnard's exact test for a 2x2 table, which is described as an option in the EXACT statement of PROC FREQ. While I can use all other options for the EXACT statement, the option BARNARD seems to be unavailable.

    I use SAS 9.3 for Windows. Is anybody aware of that problem?

    I know about the controversies on the use of Barnard's test (or alternatives) as compared to Fisher's exact test and try to avoid a discussion on that issue here. I have to use Barnard's test for one project.

    Thank you in advance!

    Umar Yusuf Madaki · Putra University, Malaysia

    try SAS 9.1 as recommended in one article (Analysis of 2 3 2 tables of frequencies:
    matching test to experimental design International Journal of Epidemiology 2008;37:1430–1435
    doi:10.1093/ije/dyn162  Published by Oxford University Press on behalf of the International Epidemiological Association
    The Author 2008; all rights reserved. Advance Access publication 18 August 2008) i read early. by JOHN LUDBROOK

  • Jan Gunneweg added an answer in Dental Plaque:
    Are there any dietry guidelines for dental plaque control counseling?

    What are the guidelines for prescribing a dietary regimen/ diet guidelines to the dental patient for plaque control?

    Food is one of the major aetiological factors in dental plaque development.Which foods should be prescribed to reduce development of dental plaque? Which food habits should be modified and how?

    Are there any evidence based guidelines / research papers for this?

    Jan Gunneweg · Hebrew University of Jerusalem

    Ankur, once returning to the use of sugar--too much of it not good for your teeth--I just learned that bread made of white wheat flour contains too about 3 grams of sugar per two slices (a sandwich), except for other sweeteners used in making that type of white bread.  I try to eat bread of whole-grain with low amounts of sugar and natrium. The problem is that in certain countries a baker can write "Whole Grain" when in fact the bread contains only less than 30% of that type of flour, whereas the rest is plain white flour. Rinse mouth and brush your teeth (nothing personal, of course). Jan

  • Can anyone tell me about methods of control adopted by Z Source networks and their general suitability?

    Can anyone tell me about methods of control adopted by Z Source networks and their general suitability?

    Vignesh Subramani · Oxford Engineering College

    Actually these two papers are complete review of till date work . But the implementation part , where do i get it? i.e logic to be used for matlab/simulink. 

  • What is the best conditions to prepare porous polybenzoxazine using freeze-drying method?

    or another procedure?

    Arezoo sh. dadkhah · Tarbiat Modares University

    This chapter may be useful

  • How to design a micro strip line with variable conductivity from one end to other end?

    how to design a micro strip line with variable conductivity from one end to other end.

    Gert Cuypers · KU Leuven

    Amit is correct: tapering a microstrip line width has a significant influence on the characteristic impedance (Zc), and can be used to make an impedance transformer. However, this effect is not only due to the changes in the conductivity, but also due to changes in the capacitance to the ground plane.

    To isolate the effect of the *conductivity* only, I think it would be better to taper the thickness (height) of the line, because this has a much smaller effect on the capacitance. Obviously this is much harder to do than tapering the width of the line, (I expect this can only be done using a metal deposition process, e.g. sputtering).

  • Didier Pelaprat asked a question in Transfer Agreement:
    Are we OK to leave all our rights on our own work to publishers?

    Are we all OK to sign Copyright Transfer Agreements to commercial, academic and Society publishers, which lead us, for instance, to have to pay again if we want use our own work, or forbid us to fulfill our mission of free access to the society?

    A trial of analysis of the scientific publishing economic sector (sorry, in french):


    The scientific publishing sector is the only sector in publishing, with advertisement, where one has to pay in order to be published. Did you remark that, according to the US law, at the bottom of each paper, it is written: "this paper si considered as an advertisement, only because it was partly defrayed by page charges".

    Are we all OK with all that?

    Why do we leave that (or make it) to occur, why we are the Editors in Chief, the subject editors, the reviewers, the boards ...  of journals?


  • Sneha Murmu asked a question in MODIS:
    How to download NDVI data of Purulia District?

    Preferably NOAA or MODIS Data.

  • Godwin Egwu added an answer in Research Governance:
    What are the challenges of IT Governance in SMEs?

    I'm working on the research IT Governance: Challenges and Implementation for SMEs. I will want several view on the governance of IT in SMEs.

    Godwin Egwu · University of Roehampton

    Hi Richard.

    Thank you for your contribution. IT Governance have so many definition. It represent the framework for decision rights and accountabilities to encourage desirable behavior in the use of IT.   

  • O. V. Dolotova added an answer in Ligand:
    Can two Pt(IV) complexes exchange chelating ligands?

    In other words, can the following reaction occur?

    (L1)Pt1(IV) + (L2)Pt2(IV) -> (L2)Pt1(IV) + (L1)Pt2(IV); where L1 and L2 are two similar chelating ligands and Pt1 and Pt2 are two distinguishable Pt(IV)-centers.

    Any references would be extremely helpful


    O. V. Dolotova · Moscow Institute of Physics and Technology

    Of course, it depends on the nature of the ligands.

  • How can I isolate flavonoids?

    I need help on suitable equipment to isolate various flavonoids in pure form so as to test it on plasmodium SPP. Which one is the best? Is it TLC or HPLC? I also need a protocol to start with if it TLC or HPLC.

    Neeraj Sethiya · The Maharaja Sayajirao University of Baroda

    You may use TLC

    Best solvent system if Ethyl acetate: glacial acetic acid: formic acid: water or butanol: acetic acid: water

    Spraying reagent: NP-PEG and 10 % KOH solution in methanol.

  • Ziad Salem added an answer in Dendrogram:
    How to estimate a similarity or distance between different dendrograms coming from hierarchical clustering?

    Dear all,

    the question is in the title!

    Thanks in advance


    Ziad Salem · Karl-Franzens-Universität Graz

    Hello, try this paper, although is it to do with classification but you cab get some ideas to apply for clustering.


    I hope it help.

    Best wishes

  • Markus Graubohm added an answer in Moisture Content:
    What is the standard lab test method to check moisture content in concrete?

    Moisture content by weight of the concrete. how i proceed that method and how i make samples to check moisture content ??

    Markus Graubohm · RWTH Aachen University

    To determine the moisture content of concrete, fragments of the test specimens are weighed immediately after the test, then dried at about 105 °C until the mass (weight) of the specimen decreases less than 0,1 % within 24 hours. From the mass difference before and after drying, the moisture content results as a mass fraction in %, relative to the dried material.

  • Marcus Nagle added an answer in Oxalates:
    How many methods to reduce acid oxalic or oxalate content in vegetables?

    I found out 2 ways to reduce oxalate by boiling in brine and boiling in brine before freezing. Could you give me some advices in this situation? Thank you so much. 

  • Wiem Www asked a question in CloudSim:
    Is it possible to simulate Multiple cloud providers in cloudsim?

    Dear all,

    I would like to know if it is possible to simulate more than one cloud provider in cloudSim.

    If yes, how to implement VM migration from one provider to another?


  • Satish -- added an answer in ISO 17025:
    How can I calculate combine uncertainty for intermediate thick pellet in EDXRF?

     I work in the government institute we are now in an accreditation process by the ISO 17025. Where is possible to find references and practice examples of how to calculate combine uncertainly and methods validation in EDXRF? We are normally using Compton peak as a internal standard for calibration. 

    Satish -- · National Physical Laboratory - India

    follow the GUM document at