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  • Viktor Chernii added an answer in Solvents:
    How can I carry cryclotrimerization reaction of acetophenones to yield 1,3,5-triarylbenzenes?

    We want to obtain 1,3,5- triarylbenzenes starting from acetophenones and their cyclocondensation reactions. Preferably should be used atmospheric conditions for this reaction. Solvent or solvent free procedures are welcome. 

    Viktor Chernii

    Hi Hiram, see:

    30 gr acetiphenone+ 30 gr aniline + 2 gr anilineHCl heat in oil bath (170-175 C) about 1 hour.  Then evaporate excess of aniline (26-28 gr) at a temperature 185-190 С.

    To system add 30 ml HOAc and boiled about 30 min. The hot solution was poured into a beaker and cooled with ice.

    Filtered and crystallized from HOAc. yield ~12 gr, ~50%. M.p. 169 C.

    Best regards,


  • Jean François Cart added an answer in Copepoda:
    Can anybody give a name to this copepoda Lernaeocera ?

    Hello, I found this parasite on freshwater Esox lucius. Is it possible to give it a name ? 

    + 2 more attachments

    Jean François Cart

    I note it, Thank you.

  • Ananta MS Pradhan added an answer in River Engineering:
    Can anyone suggest any open source user-friendly software?

    I need to draw some diagrams to show horizontal and vertical distribution of flow velocity. I will be grateful if some one suggests for it! Thank you!!

    Ananta MS Pradhan

    Golden software surfer is good solution.

  • Ranjani K. Murthy added an answer in Governance:
    Could you suggest literature on changing social norms governing gender, race, caste, religion etc?

    Sociologists describe norms as informal understandings that govern individuals' behavior in society.

    Ranjani K. Murthy

    Dear Kiran 

    Do give me a gist of Maitreyi Pushpa literature on changing gender norms.



  • Thanayut Kaewmaraya added an answer in Miller Index:
    How could I make super cell and transform the coordinates of unit cell using VESTA?

    Hello. Superiors.

     I want to make super cell structure to calculate band structure.

    I have been searching for it and found the paper attached (E.S.Tasci, "How to prepare an input file for surface calculation").  This paper was written to tell how to make super cell toward desired direction(means 'miller index') using VESTA program.

    If you are familiar with VESTA or read this paper,

    please help me for 2 problems below.

    1. I made a primitive cell consisting of 2 atoms and changed it to 2x2x2 super cell in 'edit -> edit data -> unit cell' option. I expected I will get a super cell consisting of 16 atoms (2 atoms x 2x2x2 = 16 atoms) but I got 64 atoms or more after I exported the structure to POSCAR. Did I miss something important to get atoms and coordinates I want?

    2. I am having hard time to understand how to transform the old coordinates to the new coordinates following by procedure explained in the paper attached. I can't match the result in the paper(the matrix in page 8) from originals (table 2). Could you explain it to me?

    I have just started my study for DFT. So I hope I could get helps from this community.

    Best regards,

    Thanayut Kaewmaraya

    Dear All

    A supercell can be easily constructed by VESTA by the following steps:

    1) Preparing the unit cell, e.g., in VASP POSCAR format

    2) Select the menu "Edit" and then "unit cell"

    3) Select the button "Trasform" and them enter you size of the supercell, e. g., 3x3x3 to the the diagonal elements of transformation matrix. Click OK

    4) There is an option to export the coordinates in the VASP format.

    Regarding the construction of the surface, you can follow the steps in the link below. It is comprehensively written by Emre S. Tasci.


    Hopefully, these may help you.

    Best regards,


  • Martin Jung asked a question in Environmental Processes:
    From a spatial view: What can be considered the "landscape scale" ?

    Something I always asked myself: In the field of Landscape ecology. How do we define and parametrize the "landscape scale" from a spatial view? What counts as a landscape and what is just the minimal covering area of all field sites? Are landscapes intrinsically defined by the social-ecological boundaries of humans that interact within them or is there sth. like a general theorem that defines the spatial scale (per ecological or environmental process) that a landscape can operate on?

    Appreciate any cool references to seminal or review papers that investigated this.

  • Thierry-Pascal Baum added an answer in Image Analysis:
    Any advice on Image Training: Labeling of patches while extracting patch features?


    I'm trying to do simple training on image's patches and label them.

    However, I can't think clearly of a way to assign label to image patch while extracting features..

    Any ideas?

    Thierry-Pascal Baum


    Could you give some more detail please ?

    For example, what will you use to do your training ? A software as a simple user, a software that you create yourself , etc. ?

    There are many solutions, depending on what you want to use : do you want to program the solution by yourself, use a dedicated software (neural nets, statistical package, OpenCV, etc.), what type of methods do you want to use for the training...

    To be able to help you, you need to give more details on the training context.

    For example, if program yourself and you are extracting patches from an image, its easy to label each patch as you extract them when browsing the image and get the parameters for the training.

  • Jack Silver added an answer in Citrates:
    How to remove citrates from citrates of alkaloids?

    The alkaloids extraction form the plants where a step produces citrates of alkaloids and highly polar quaternary alkaloids (as iodides). I am trying to get citrates- and iodides-free alkaloids? How I get it?

    Jack Silver

    Another thing to try is adsorption on a strong cation exchange column (SCX), with elution with excess of a salt containing the desired counter-ion or with ammonium hydroxide if the free-base is desired

  • w.s.l. Boyer added an answer in JCPDS:
    What kind of JCPDS card has been used? this is a XRD of a biochar named rice bran carbon. Thanks!

    What kind of JCPDS card has been used?

    w.s.l. Boyer

    I must agree with Mirabbos that your question is unclear - it makes no sense:  "which kind of JCPDS was used"?  Answer: none, there are no reference lines on the pattern shown.  I don't think that is the question you are asking, so please try again with your question.

  • S. B. Arnason added an answer in Magnetron Sputtering:
    What are the non-equilibrium conditions for thin films obtained by magnetron sputtering?

    in some books it is said that the magnetron sputtering processes are carried out in non equilibrium conditions, but never are specified which ones; so that is my question, what are these non equilibrium conditions?, and how can I relate them with the phase diagrams?.
    are these conditions contradictory?, in the sense that the phase diagrams are made in equillibrium conditions, and the thin film processes are not. g  

    S. B. Arnason

    To grow a thin film at equilibrium would take an infinite amount of time. The driving force that pulls the species to be deposited from one phase, vapor or liquid, into another phase, the solid film on a substrate, depends on the free energy difference between the two phases. As you move towards equilibrium that free energy difference goes to zero and as a result so does the growth rate.

    For a thin film you can think of this as the deposited species not having enough time as mobile species on the growth surface to explore the energy landscape and find the attachment point that will minimize the free energy of the configuration before mobility is lost to cooling through contact with the substrate. The higher the temperature of the substrate the greater the surface mobility and the more reconstruction can occur to get you closer to an equilibrium thin film. Slow growth at high temperature -> closer to equilibrium.

    But, non-equilibrium can be a virtue. Often the crystal structure or film morphology desired is not the equilibrium phase; so, non-equilibrium growth techniques allow for the formation of materials that are not achievable in other ways.

    Sputtering is a ridiculously complicated process in its details. My advice is to be aware of that complexity but not to worry about the details. Probe the space of possible materials by varying the parameters that you can control and characterize the results carefully. Looking at what you get and how you got it can not only solve the problem at hand but will also lead to new protocols for growing new materials with disinct properties.

  • Vittorio Porciatti added an answer in Electroretinography:
    Does anyone know any studies which used a 20 degree stimulus size for eliciting focal electroretinograms?

    Please does anyone know any studies which used a 20 degree stimulus size for eliciting focal electroretinograms?

    Vittorio Porciatti

    If you are interested in 10 deg focal ERG, then you might check the attached reprints.

    + 1 more attachment

  • N. V. Chezhina added an answer in Cobalt:
    Effective Nuclear Charge experienced by the 3d-orbital in Cobalt atom

    According to Slaters equation for calculating effective nuclear charge (Z*=Z-S), 3d orbital of Cobalt has a value of 6.90. Clement et.al in 1963 proposed a modified version of Slaters rules and according to them it is found to be 11.855.

    My question is why these two approaches are giving values that can not be compared, even though the values for 3s (15.75 vs 14.322), 3p (15.75 vs 13.435) and 4s (3.90 vs 5.576) are comparable.

    Any advice will be greatly appreciated......

    + 1 more attachment

    N. V. Chezhina

    You must look into the tables of Slater's constants anywhere and use them. Up to now everybody was content

  • Kim Oanh Hoang added an answer in Urbanism:
    What are the differences between theories of urban planning and the practice in private companies?

    How private urban projects led by companies differ from the projects in scientific institutions and what are the effects of these urban projects on the social and physical environment of the city. It is known that economy and human requirements are main concepts in urban planning field and we most balance them but what is really happening is a struggle between them.

    I am doing a master thesis about this subject and I would like to get any help by giving ideas, references or telling the new concepts on this debate. 

    Thank you in advance.    

    Kim Oanh Hoang

    Dear Hasan,

    I don't really understand your question. Which one do you wanna know? The differences between the reality and theories or the reasons led to them?

    If it's the first issue, I think you had the answers.

    If it's the second one. In my opinion, this problem comes from many aspects. One of the most important reasons is that the political factors. Furthermore,  the data collection is really weak in developing countries. It's evenly not much exactly. As a result, the planning and reality don't match each other. 
    In fact that, there are so many reasons. They're different, depending where is your study area.

    Hope that this answer satisfy and match with your idea.

  • Jack Silver added an answer in Preparative HPLC :
    How do I decolor Aloe Vera extracts?

    How to decolorize Aloe vera extract using for any herbal formulation? It need to be run in semi preparative hplc. I am scared the coloured compounds might spoil the column, i am not sure of it but. Can someone answer both the questions?

    Jack Silver

    @ Neha;

    The easiest way to use the polyamide is to pack a very small column in methanol, dissolve your sample, run it through the column, and wash with methanol, combine the washing with the eluant. This method is useful for eliminating tannins which cause non-specific binding in some assays, but might capture some desired phenolic compounds. We generally ran our plant extracts through polyamide SPE cartridges to capture the tannins that interfered with our assays.

    Given that the activity adsorbs on charcoal, I would try running the polyamide like a silica column. Pack it just like silica gel. I packed it in water and attached it to my flash chromatography system (CombiFlash Rf-200), I ran a gradient starting with water to 100% methanol, another gradient from methanol to methanol to 100% acetone, then acetone to 100% water containing 5% ammonium hydroxide (3 gradients total). This gives you a chance to recover the activity if it gets stuck on the column, and potentially identify the class of compounds.

    if you use a glass column, this can be done with step gradients as well. The gradients give you a chance to recover the compounds that get adsorbed.

    I would also try washing your used charcoal, if you still have it, with the solvents I mention for the polyamide column to see if you get your activity back.

  • Asier Rodríguez Larrinaga added an answer in Seed Dispersal:
    How many seed traps should I place in a weeded and non-weeded area for comparison?

    The place where am doing research the area of non-weeded is very small compared to weeded area (by how much I don't know). I would like to know how I can distribute seed traps in both areas for comparison.

    For example if I have 30 seed traps how many should be in non-weeded and weeded areas.

    Asier Rodríguez Larrinaga

    Well...it really depends... As has already been said, first of all it depends on your question. Probably your question is, explicitly or not, related to density; you probably want to know if seed rain density (the number of seeds per unit area) is similar in both areas. So, you would need an equal density of traps at both treatments. This is crucial, as the comparison of 15 traps spreaded on 1 ha with 15 traps spreaded on 25 ha is hardly meaningful.

    The constraint of having the same number at each area may be important if you have a complicated ANOVA design (such as a repeated measures ANOVA or a split-plot), but is not to be kept for a simple approach (something like a one-way non-parametric test or a t-test). For complex designs, modern GLM and GLMMs also allow for unbalanced designs without much problem.

    So, I would say you have two sensible options:

    * Spread half of your traps over the non-weeded areas and the remaining traps over an area of the same size within the weeded areas.

    * Spread a number of traps over the non-weeded areas, calculate the resulting trap density, and spread a different number of traps over the weeded area, with a similar density.

    Given the uncertainty on the area of the weeded area, probably, only the first approach is feasible.

    On the number of traps needed for the study...that is a question that is impossible to answer without some preliminary data. The number of traps neede will depend on the number of seeds captured per trap and the minimum difference we need to detect between both treatments. You will need both data (even if guessed) to carry out a power analysis to figure out how many traps you need.

    Good luck!


  • Harry ten Brink added an answer in Climate Variability:
    Where can I get climate variables for the Younger Dryas period (circa 14.000 years BP)?

    In my study I am trying to verify whether there have been climate refugia for a species. Unfortunately, publicly available databases only have data for the Last Glacial Maximum (circa 21kya), the Holocene (circa 6kya) present and future. Considering that the Younger Dryas were a period of forest (vegetation) contraction and this could influence the distribution of my targeted species, I think it would be important to include it in my study. Unfortunately, I can't find climate variables for this period. Can anyone provide any suggestion?

    Thanks in advance!

    Harry ten Brink



    Younger Dryas deglaciation of Scotland driven by warming summers

  • Gert Nolze added an answer in Single Crystal:
    Is there any software to generate the single crystal surfaces from the bulk structure?

    Software to generate the single crystal surfaces
    Does someone here know it there is any software to generate the single crystal surfaces from the bulk structure?  Thanks in advance!

    Gert Nolze

    @ D. Aquilano: the papers look very interesting and quite convincing. Could you say some words about well-known limitations (from your point of view)? We had a discussion somewhere else and I used the argument that e.g. calcite forms hundreds of different habits which you certainly cannot derive from this assumption, or can you? Thanks in advance, Gert

  • Daniel Goodwin asked a question in Qualtrics:
    Can anyone recommend a crowdsourcing platform for recruiting participants for a survey built in Qualtrics?

    The sample will need to be representative of London or of at least the UK

  • Imad Tarhoni asked a question in Immunoassay:
    Does anyone know the exact way to measure the value of cross reactivity in multiplexed immunoassay?

    I'm developing multiplexed bead based indirect immunoassay for four target cytokines and developing sandwich immunoassay for each. I have measured the performance of each individually and I am evaluating their performance in multiplexed form. While I am clear about the experimental design to evaluate this at different levels( capture Ab, cytokine,and detection Ab) However, I'm looking for the appropriate way to calculate the cross reactivity values.   

  • Roland Kallenborn added an answer in Supercritical Fluid Chromatography :
    Does anyone have experience in modern SFC-MS instruments?
    Waters say that their SFC-MS instrumentation is much better than GC-MS and that I should by a SFC-MS instrument instead of GC-MS/MS. I don't understand this, can you let me know your opinion?
    Roland Kallenborn

    Check this references for your validation:

    + 3 more attachments

  • Diego Manfredi added an answer in Heat Treatment:
    What is the solution used in Al 6063 T6 for precipitation hardening?

    I am doing project of improve the fatigue strength of Al 6063 T6 by  precipitation hardening

    Diego Manfredi

    As reported in ASM Metal Handbook, this easily extrudable alloy nominally contains 1.1% Mg2Si. Its solution heat-treating temperature of just over 500 °C (930 °F) and its low quench sensitivity are such that this alloy does not need a separate solution treatment after extrusion but may be air quenched at the press and artificially aged to achieve moderate strength, good ductility, and excellent corrosion resistance.

  • Vijesh Krishnamurthy asked a question in Telemedicine:
    Can anyone brief me about drawbacks on Telemedicine?

    I would like to do a research in Tele-medicine and I am in the progress of analyzing the drawbacks of the implemented technology. need experts help. Please help me.

  • w.s.l. Boyer added an answer in Nanodiamonds:
    Sharp peaks in XRD but no evidence from HR-TEM. Why?

    My SPS sample consists of nanodiamond reinforced in aluminium. XRD gives sharp peaks for aluminium but in HR-TEM i see only nanodiamonds. No d-spacing corresponds to aluminium. If aluminium matrix is amorphous than why do XRD presents a conflicting result? 

    I have attached the HR-TEM micrograph.

    w.s.l. Boyer

    To summarize a few key points in one place:

    1. Do you have Al sample holder?

    • If you do not use Al sample holder, you can trust the XRD.  You do have crystalline Al.
    • If you did use Al sample holder, this can be ok, if your sample is thick enough and covers the holder completely.  If the incident x-rays can reach the sample holder, either by penetrating through the sample or where the Al holder shows around the edge of the sample, then you will get Al peaks from the holder.

    2. HREM sample preparation and data acquisition and analysis can be challenging and is certainly non-trivial.

    • Follow Flemming B. Grumsen's advice in the post just before this one.
    • Please be careful talking about amorphous aluminum.  Aluminum will always be crystalline in its pure form (above a few K).
    • Any fresh Al surface will immediately become oxidized on exposure to air.  Since TEM samples must be very thin, you may be looking at an area where all of the Al has been oxidized between the sample thinning and the microscope.
  • Sugata Sanyal added an answer in Cryptography:
    How hidden vector encryption can reduce ciphertext size as compared to brute force approach available in Boneh's Conjuctive predicate paper?

    I have thoroughly read the paper Conjunctive, Subset, and Range queries on encrypted data (Boneh, Dan, and Brent Waters. "Conjunctive, subset, and range queries on encrypted data." Theory of cryptography. Springer Berlin Heidelberg, 2007. 535-554.). I can't differentiate the trivial brute force scheme and HVE scheme in terms of ciphertext size. I found the improvement in token size.  

    Sugata Sanyal

    I searched the internet thoroghly as well. Boneh is one of the leading author who has worked in this area. Will you please look at the other papers there ? Hope it helps.

    Prof. Sugata Sanyal, 
    ​Mailto: sanyals@gmail.com 
    Homepage: http://www.tifr.res.in/~sanyal 
    Skype: sanyalsugata 
    Member, School of Computing and Informatics' "Brain Trust", University of Louisiana at Lafayette, USA
    Honorary Professor: Indian Institute of Technology, Guwahati
    Member, Senate, Indian Institute of Information Technology, Guwahati
    Distinguished Scientific Consultant :International Research Group: ​​Bucharest, Romania​​
    Innovation Mentor, TotalStart Entrepreneurship Ecosystem Developers
    Senior Columnist: the Indian Economist
    Research Advisor, CTO,Tata Consultancy Services, India (2012-2015)
    Adjunct Professor: Indian Institute of Technology, Kharagpur(2013-2014)
    Professor:School of Tech. & Comp. Science,Tata Institute of Fundamental Research (1973-2012)

  • Maksym Plachynta added an answer in Ketone Bodies:
    May I have a question on DMSO metabolism?

    When I inject DMSO intraperitoneally into a mouse, I can always sense a smell of fruity odor several hours later. This recalls me of the smell from acute ketoacidosis, but I am not sure about this is caused by ketone bodies in this case.

    Maksym Plachynta

    DMSO when oxidizes spontaneously by oxygen from the air, produces some substance with garlic smell. I guess, that in an animal organism DMSO may get involved in some more tricky reactions which result in a fruity smell.

    By the way, do you inject pure DMSO, or diluted with normal saline? In my experience, injection of 100 uL pure DMSO to mice i.p. to mice lead to severe pain to animals, so I switched to 10% DMSO (+ drug) in sterile normal saline. Mice seem to be fine with it,

  • Petra Disterer added an answer in Primer Design:
    How can I get a primer to target FGFR2-IIIb isoform of FGFR2 gene for qRT-PCR in mice?

    My lab is looking to study FGFR2-IIIb expression in mouse mammary glands via qRT-PCR. I'm having trouble designing primers that will only target this specific isomer of FGFR2. How would I go about targeting this specific isomer or is there a primer design that already exists and is used by labs to target FGFR2-IIIb?

    Petra Disterer

    Dear Shrusti,

    Could you elaborate on what exactly the problem is? Is it general understanding on how to design isoform specific primers or a problem with the particular sequences?

    I can help with primer design for detection of splice forms...

    In case you are having trouble with particular sequences, could you provide the sequences for your targets? Or perhaps accession numbers for your sequences?

  • Sugata Sanyal added an answer in Entrepreneurship Development:
    Is there any information flow between social networks and entrepreneurship?

    many researcher's had identified that social networks play an important role in entrepreneurial emergence but how this information flows from social networks to entrepreneurs? is there any conceptual linkage between them?

    Sugata Sanyal

    Please refer to the Handbook of  Entrepreneurship.


    It greatly relates with your question. Hope it helps. It is also a highly cited article.

    Best wishes,

    Prof. Sugata Sanyal, 
    ​Mailto: sanyals@gmail.com 
    Homepage: http://www.tifr.res.in/~sanyal 
    Skype: sanyalsugata 
    Member, School of Computing and Informatics' "Brain Trust", University of Louisiana at Lafayette, USA
    Honorary Professor: Indian Institute of Technology, Guwahati
    Member, Senate, Indian Institute of Information Technology, Guwahati
    Distinguished Scientific Consultant :International Research Group: ​​Bucharest, Romania​​
    Innovation Mentor, TotalStart Entrepreneurship Ecosystem Developers
    Senior Columnist: the Indian Economist
    Research Advisor, CTO,Tata Consultancy Services, India (2012-2015)
    Adjunct Professor: Indian Institute of Technology, Kharagpur(2013-2014)
    Professor:School of Tech. & Comp. Science,Tata Institute of Fundamental Research (1973-2012)