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  • Viswanath Devan added an answer in Fluid Dynamics:
    Anyone have study materials for non-equilibrium in hypersonic flows? Can anyone suggest some books?

    I want to study non-equilibrium phenomena in hypersonic flow. Please provide me the materials related with the same.

    Viswanath Devan · Indian Institute of Technology Guwahati

    You can go through the references given in attached paper

  • Can anyone please provide inputs on six sigma black-belt in pharmaceuticals?

    how to implement six sigma in pharma industry

  • Surender Pratap asked a question in MOSFET:
    Can CNt having diameter 3 or 4nm can work like MOSFET?

    what will the dielectric constant in the cnt whose diameter is 3 or 4nm,can this gives rise to same curves of MOSFET?

  • Danish Hussain Asefi asked a question in Drawing:
    Should a review paper include already published figures???

    Figures play important role to let other understand easily, what we mean!! some figures are not based on data they are conceptual in nature, usually authors draw to visually represent a concept, in case of review paper is it OK to draw ones own figure to illustrate a concept and include in the paper? or a review paper should  'only' include already published figures???

  • MOHD BELAL Haider added an answer in Aspen Plus:
    What are the parameters or the property required or need to define for simulation of absorption of co2 in aspen plus 8.6?

    while simulating the absorption of co2 in Aspen plus 8.6 what are the property which need to be define before simulation . 

    is regression required ? 

    MOHD BELAL Haider · Rajiv Gandhi Institute of Petroleum Technology

    thank you sir, for the answer . is there  any other property other then thermodynamic model which need do be define ?

  • Why does dilution of homoeopathic medicines enhance their potency? Is this not against scientific phenomena?
    I have been told by homoeopathic practitioners that dilution and potency of homoeopathic medicines is inversely proportional. This means the higher the dilution the more potent the medicine will be and vice versa. I have doubts which may be due to my bias because personally I did not find any experience of homoeopathic medicine effective.
    Salvatore Chirumbolo · University of Verona

    Because Prof Paolo Bellavite most probably resorted to his attorney's aid  (Prof. Picotti, University of Verona, a colleague of him...) to remove my Comment. The Comment  which you are referring to, concerns my reply on Eur J Int Med on a fake statement from Bellavite (http://www.ncbi.nlm.nih.gov/pubmed/24429058) reporting verbatim: "This Garattini et al. letter begins by arguing that “Peter Fisher and Paolo Bellavite cite a paper of ours [2] as claiming possible damage from homeopathic medicines”. As a matter of facts, the cited letter from Fisher and Bellavite “Homeopathy: Where is the bias?”in press in Eur. J. Int. Med. (PMID: 24433702) does not even mention any Garattini’s paper". As you may realize from the attached files herein, Ballevite stated exactly what he denied in Pubmed Commons. I reported this truth (as scientists are ethically obliged to do).but Pubmed Commons removed it. You can see also that the original title of my reply was "Reply to Paolo Bellavite" and it was completely revised WITHOUT my agreement... Herewith attached my original paper, fixed personally by Prof Mannucci and sent to my electronic address..You can see that title was not revised...).

    You asked me the truth and the truth is here. Sorry.

    Sincerely, I do not understand why homeopaths are forced to demonstrate their scientific reputation by drawing upon backbitings....probably because they have no further sound issues to be addressed except for a very long surge.... (http://www.paolobellavite.it/responses.html)

  • Amit Kumar Sharma added an answer in Nanoparticles:
    A liquid sample can be used for SEM ?

    Electron microscopy Nanoparticles 

    Amit Kumar Sharma · Indian Institute of Technology Bombay

    We have tried to capture liposomes in TEM. I think it should work for you as well. for SEM, try minimal diluted sample dried in air or under IR. if liposomes, try air drying. this should for you.

  • Is the electron mass strictly of electromagnetic origin?

    There exist   theoretical evidences that this hipothesis is true, especially, it is strongly supported by the Casimir type electron stability mechanism suggested by Prof. hal Puthoff in his nice work: Putho¤ H.E. "Casimir vacuum energy and the semicalssical electron". Int J Theor Phys, 46, 2007, p. 3005-3008, as well as in the work by Valerii B Morozov,  2011 Phys.-Usp. 54 371 doi:10.3367/UFNe.0181.201104c.0389
    "On the question of the electromagnetic momentum of a charged body"

    Mohamed El Naschie · Alexandria University Alexanderia Egypt


    this paper may be of help in understanding what i mean..... 

    Chaos, Solitons & Fractals
    Volume 32, Issue 3, May 2007, Pages 893–895

    Rigorous derivation of the inverse electromagnetic fine structure constant using super string theory and the holographic boundary of E-infinity
    M.S. El Naschie1
     Show more



    An extremely simple and elementary but rigorous derivation of the inverse electromagnetic fine structure constant is given using super strings and the holographic boundary.

  • Zhifei Luo asked a question in Lipofectamine:
    Can I sort cells after electroporation?

    I used lipofectamine 3000 to transfect cells. However, the transfection efficiency is low. Electroporation gave me better efficiency but the cells grown relatively slowly. Cell sorting is harmful to cells. Is it a good idea to use electroporation instead of lipofectamine before cell sorting.

  • Yousueng Han asked a question in Factor Analysis:
    Do you think how can I use factor analysis when scales are different?

    For example, 3 factor: one is percent scale, the second factor is elasticity scale, the third is number 1~4.

  • Ahmed Almurshedi added an answer in EEG/ERP:
    What is the response of the oddball paradigm of 50% target probability?
    What is the difference in response of the oddball paradigm (80% non target and 20% target) with stimulation of 50% target probability in literature? Any reference paper would be a great help.
    Ahmed Almurshedi · Universiti Teknologi Malaysia

    Thanks for your response  Francesco

  • B.R. Rajeswara Rao added an answer in Friendship:
    Would you kindly join me in wishing a happy birthday, and pay homage to our dear RG friend LJUBOMIR JACIC?

    i just remembered that our dear friend Ljubomir was born on the 28th of March, a few years ago.

    I pay tribute to an inteligent, sensitive and sensible sweet adorable Serbian.

    You, dear sir, are a very special person, that I feel honoured to have met, and  thank you for letting me be your unconditional admirer !

    (I do hope that Î got the date right.... If not, please consider this a singular extravagant note of friendship, )

    Yours, truly, with warm respects !


    B.R. Rajeswara Rao · Central Institute of Medicinal and Aromatic Plants

    Belated Birthday Greetings to Ms. Rajshree. May God bless you and Your family with Health, Happiness, prosperity and everlasting Peace.

    Good luck. 

  • Mumtaz Danish added an answer in Reaction Kinetics:
    How do I determine rate of reaction or kinetics of reaction without taking into consideration the reactant concentration?

    can we find out rate of reaction only on product  concentration

    Mumtaz Danish · University of Karachi

    Dear Pattanaik, I have performed some example calculations for you. Hope this will be beneficial to you. 

    For theoretical details there are many good books on the topic for example Elements of Chemical Reaction Engineering 4th Ed - H. Scott Fogler

  • Can we use entropy as an image fusion metric ?

    Some of the researchers are using entropy as an image fusion metric, but some researchers are mentioning it is not a  fusion metric. Which one is correct?  

    please suggest me some good fusion metrics......

  • Is anyone familiar with four wave mixing equation?

    I'm working on four wave mixing effect in fiber optic, and I'm trying to use the attached paper. The summation in equations 35 and 36 is not clear to me.

    Many thanks.

    Khalil Safari · University of Tabriz

    Four-wave mixing (FWM) is a phenomenon that must be avoided in DWDM
    transmission, but depending on the application it is the basis of important second-generation
    optical devices and optical device measurement technology. 

  • Vibhor Malviya asked a question in Displacement:
    How can I define circular tool-path in Abaqus-CAE?

    I am simulating single point incremental forming and intend to get the profile "truncated-cone" on sheetmetal. How do i define the tool-path for this?

    For profiles like truncated-pyramid, when tool has to move only in straight direction i can use displacement / rotation.

    In the attached picture, Left: truncated cone. Right: truncated pyramid. 

  • Are there any option to learn systemic review and meta analysis?

    I am from Bangladesh. There is no such expertise and option to expose to systemic review and meta analysis. We are still naive to those procedures! Are there anybody doing that and promoting such!

    Rajat Sanker Roy Biswas · Chattagram Maa Shishu O General Hospital, Agrabad, Chittagong, Bangladesh

    Sir, Thank you all! I think, it is better to do a meta analysis with  at least 10 publications as per Mr Jan! There are some free software also! Then let me try and wish you might assist me in need!   

  • Do you know the qualitative researches done in the field of pre-service teacher education specifically related to practice teaching?

    I am interested in the field of qualitative research. So, please help me to suggest the qualitative researches related to pre-service teacher education.

    Miftachul Huda · Universiti Brunei Darussalam

    Dear researcher,

    Below is some articles regarding pre-service teacher based on qualitative analysis.

    Kind regards.

  • Medical image data base for image fusion?

    where can i get medical image data base for the purpose of image fusion ?

  • Hasmukh Patel added an answer in Mitral Valve:
    What precautions are to be taken in mitral valve replacement in case of sickle cell?

    Thank you. 

    Hasmukh Patel · u.n.mehta institute of cardiology & research centre

    Thanks to all for providing such a detailed information. it helped me a lot to successfully conduct the case & safe extubation just 3 hrs after surgery. everything went uneventfully & we didn't require blood transfusion.

  • Nengah Parta added an answer in Social Pedagogy:
    Is open-ended instruction a model of teaching?

    In my opinion, a model of teaching should consist of: (1) syntax, (2) social system, (3) principles of reactions, and (4) support system. Therefore, if someone claims that open-ended instruction is one of the models of teaching, the syntax should be clear. If it is true, I don't know for sure the syntax of open-ended instruction. Is there someone who can clarify this issue? 

    Nengah Parta · State University of Malang

    Kalau hanya "open-ended instruction" belum bisa dikatakan model pembelajaran, karena itu bisa jadi hanya satu bagian dari bentuk interaksi yang dipilih guru. Tetapi kalau dari "open-ended instruction" dibangun teori (Teori Pembentukan Model), sehingga diperoleh sintak yang bercirikan "open-ended instruction", dilengkapi dengan sistem Sosial, Prinsip Reaksi, dan Sistem Pendukung, maka "open-ended instruction" aka menjelma menjadi sebuah model.

  • What are the basic differences between small signal and large signal analysis of different transistor?
    Where do we use small signal model or large signal model? Why? What are their output behaviors?
    Jatinder Preet Singh · University of Ottawa

    If there is difference between S parameters graph calculated vs the s parameters graph given in data sheet in an amplifier in small signal analysis, what does it mean?

  • Mir Sayed added an answer in Cycloaddition:
    What is the function of a base in CuAAC click reaction?

    Could anyone please tell me the function of a base like "DIPEA, Et3N etc." in Cu catalyzed alkyne-azide cycloaddition reactions. In some of CuAAC reactions base is required while in some cases it is not required, why? 

    Mir Sayed · Southeast University (China)

    It's okay and thanks for the reply. I will find it....

  • When it comes to simultaneity is Einstein correct or is Dingle correct?

    Albert Einstein claimed in 1905 that a single event can occur simultaneously at different times within two inertial reference frames moving relative to one another. In 1950 Herbert Dingle argued that different times cannot be simultaneous. I have analysed this conflict by deriving the Lorentz equations using both points of view. According to this analysis Dingle must be correct. See youtube presentation of this analysis at  https://youtu.be/4XLYzhHQ64Y

    Manuel Morales · TemptDestiny.com - Prephysics Research

    "The selection to drop the coin in the cup (or at the rim) is a selection of initial conditions. These conditions, according to your reasoning, exist since you made the selection!"

    Correction Erkki, the cup serves as an example of cause and effect whereas the rim of the cup provides the potential of a selection and the coin represents the act of a selection (cause). When both simultaneously exist, then and only then, does the initial condition come to exist, not a moment before because a dichotomy cannot exist until both halves simultaneously exist. The bottom of the cup represents the effect of the selection made which we can then observe/measure. If at the final moment prior to the coin pairing with its potential the cup blows away, you do not have either a direct or indirect selection.

    When football fans voted for their team, they voted for the potential of their team making it to the Super Bowl. However, as the unambiguous empirical evidence has shown, an act cannot exist without its potential and vice versa. A direct selection event did not take place eleven out of twelve direct selection attempts. This means that energy is not conserved and the existence of time is not invariant.

    However, if I had only conducted indirect selection attempts as commonly practiced in scientific experiments, the findings show that there would have been twelve out of twelve selection events which would have included the one direct selection event. Without knowledge of which mutually exclusive selection event caused the effects observe, I would only be able to use conjecture to correlate the cause of the effects as is the case with all particle experiments.

    Fundamentally physics only acknowledges what it can measure while at the same time uses what it cannot measure in order to search what it is looking for. 

  • Kaoru Aou added an answer in Isocyanates:
    How can I predict the molecular weight of the final PU foam?

    I would like to learn about the way we can predict the MW of PU foam,

    For example, I want to make a bulk of PU foam having density 32kg/m3. How much volume of polyether polyol and isocyanate that I need. Of course, it also comprises catalyst, blowing agent, surfactant, filler.... but I don't understand how we can calculate that when use physical blowing agent, it will diffusion out of the PU foam after processing finished.

    Kaoru Aou · Dow Chemical Company

    I agree with A. Bouaziz.  @KDH: it sounds like you're trying to figure out how much water & physical blowing agent to add.  Water will react with isocyanate to eventually form CO2 gas, or else evaporate into steam.  So every 1 mole of liquid H2O = 1 mole total of CO2 gas and H2O gas (steam).  

    Your foam density is simply mass of formulation divided by foam volume.  You can estimate the total foam volume very well from the ideal gas law (V = nRT/P) , if you know your maximum reaction temperature (varies a lot -- also, your physical blowing agent acts as a refrigerant and counteracts the reaction exotherm, thereby lowering the final temperature.  In many cases, without physical blowing agent, your final temperature can be from 120 to 200 degC depending on your water content).  P can be estimated to be 1 atm (if you're at sea level -- will be lower as you go up in elevation, especially in mountainous areas).  So the rest is straightforward math.  Just keep in mind that temperature can go up really high as you add more water, so that you need to be very mindful of fire safety when you do this.

    Some additional useful links on this topic are attached below.

  • Vibhor Malviya added an answer in Abaqus:
    Can one suggest what might be wrong with the analysis on Abaqus, as the sheet is not showing any plastic deformation even after 4mm depth of cut?

    I am simulating Single point incremental forming on Abaqus CAE. Analysis completes successfully but i am not getting any plastic deformation on sheet.

    I gave an absurd value of 4mm depth of cut just to see what happens and still the sheet only undergoes elastic deformation.


    Please suggest relevant changes. Thank you in advance. 

    Vibhor Malviya · SRM University


    Boundary conditions is "encastre" on sheetmetal edges. and i have defined tool path. Process i am trying to simulate is Single point incremental sheetmetal forming.

  • Vibhor Malviya added an answer in Abaqus:
    How to define plastic values of steel 37 and 52 in abaqus?

    Dear All

    I want to enter the plastic values of steel 37 and 52 in abaqus.

    Does anyone has these values  in the following format ?

    Yield stress       plastic strain



    Vibhor Malviya · SRM University

    From stress-strain curve, you can calculate these values. I suggest you check the abaqus documentation to get the exact formulas. Consistent units can be maintained, minimizing the chancces of error.