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  • Donggyu Jang added an answer in Proton:
    How do you calculate the total collisional cross section for the neutrals?


    I'm trying to calculate the total collisional cross section of the hydrogen atom impacted with the proton. (ion of the hydrogen plasma)

    I've found many good papers but they're showing specific cross section, for example, total cross section when n = 1 state is direct-excited to n = 2 when the proton impacts on the hydrogen atom.

    The original motivation of this calculation is to compute the diffusion coefficient of the ion in hydrogen plasma and I became confused of concept of the total cross section.

    In order to obtain proper cross section for my purpose, Should I sum up all cross sections for possible excitations or average them?

    I guess the latter is right since there are infinite possible excitations such that the all sum up should results in infinite value.

    Donggyu Jang · Gwangju Institute of Science and Technology

    Thanks people! And I'll better give you the detailed circumstance for consideration.

    I'm dealing with the hydrogen-discharged plasma which plasma temperature would be ~ 2 eV. I believed species are in the Maxwellian distribution since LTE criteria suggested by Hans R. Griem shows our plasma should be in LTE. Most of the neutrals are in ground state and ~ 95 % of the charged species doesn't have enough energy to excite neutrals to n = 2 state.

    In this case, should I consider only elastic collision or also include charge exchange in proton-hydrogen collision? I've tried to calculate the proton-neutral collisional frequency as precisely as possible for diffusion process.

  • Mehmet Uğur Toprak asked a question in Geopolymers:
    Does any one know about heat insulation properties of fly ash geopolymers

    any industrial heat insulation geopolymer boards you know?

  • Vikram Zaveri added an answer in Free Will:
    Does anybody working on the concept of "Free Will" , if so then what are there few simple experiments to check the existence of "Free Will" ?

    Hello everyone , I would like to assess the concept of  "Free Will" for humans by experiments similar to "Ants in the Box" for insects and observe their behaviour based on artificially created situation. Already I am working on assigning this concept to electronic circuitry by to modes , 1. Requirement mode and 2. Free will mode. Can anybody give suggestions on simple experiments to be carried by humans?

    Vikram Zaveri · Independent Researcher

    Nordin. Yes, it does take some free will to follow the will of God. This is explained as follows. A cow is grazing in a field and is free to move here and there. But she is tied to a post with a long rope. So as far as the rope permits, she is free to move around.

    This definitely has relation to compulsion and addiction. There are different grades of addictions. There are lower grades and higher grades. No one in the world is free from addiction. The Saint himself is addicted to God. Here comes the question of knowledge and ignorance. As a person acquires knowledge about the world around him, he decides for himself the form of addiction which he considers to be the best. For example the married man is addicted to his wife and children and he thinks that is the best thing for him. This is because his level of knowledge does not allow him to think of any other option as higher than the family life. The case of a monk is differnt. He thinks there is something higher than the family life so he shoots for that. So the lower form of addiction can be given up only when the knowledge of higher form of addiction is acquired. If you have a job and someone tells you to give up the job, you will not feel like giving up. But if you are offered a better job which you also perceive as better job according to your knowledge and understanding, then you can quickly switch.

    Many get turned down when they here about God and Salvation etc. because they have not acquired sufficient basic knowledge about this subject. There is also another aspect to this and that is the capacity to understand. Everyone does not have the same capacity. This capacity developes gradually and slowly. You may
    see some people spending their entire life in some lower form of addiction and then die. What about them?  Here comes the theory of rebirth. This kind of knowledge and understanding are developed over many births. This is why you find some people behave like Saints right from their childhood.

    In short, everyone is seeking joy, happiness, pleasure, and bliss according to their own understanding. This also includes monks and Saints. Joys and happiness of this world are transient and immpermanent. When this are pursued it also fritters away lot of energy and makes the mind more and more weak. This results into condition described by you -- They know it is bad, they want to stop but it's just not possible; almost like they have no free will... -- When the person stops accepting the joys of this world, he conserves lot of  energy which he can direct towards higher pursuits.

  • Robert Hennig added an answer in Drug Carriers:
    Can we do nanoparticle mediated drug delivery in eye?

    Nanoparticles has been used as a drug carrier but how can we use it in eye

    Robert Hennig · Universität Regensburg

    If you want to get into the vitreous you'll probably need intravitreous injections as nanoparticles usually cant cross the cornea. Putting nanoparticles in artificial tears will only be a topical application

  • Yi Wu added an answer in Tectonics:
    How can I interpret driving factors of a paleoclimate record's long-term trend?

     For example, when we need to distinguish which one is the dominant driving factors for a late Cenozoic record, tectonic activity or global cooling, what is the judgement criteria

    Yi Wu · Chinese Academy of Sciences

    Thank Dr Bothun and Dr Buchwitz for sharing your thoughts. The references you suggested are very helpful.

  • Andrey A. Kondakov added an answer in Small Mammals:
    How can I estimate population abundance when the sampling effort increased during the study?

    I am analyzing a 16-year data set of small mammals in a tropical forest. This study started in 1997 with a fixed number of traps in the study area. In 2009 we added more traps in the study area with the purpose of capture some understory small mammals (some of them were also captured in the forest floor). I have no doubt that the increase in the sampling effort in the study area will have an effect on the number of individuals captured and consequently on the population abundance estimates. So, my question is: How can I estimate population abundance when the sampling effort increased during the study?

    Andrey A. Kondakov · Russian Academy of Sciences

     "Leonid Voyta" <desmana.zin@gmail.com>: Relative abundance. Need all the catches for each year converted to 100 traps per day. After thet we can compare properly.

  • How to install NS in my computer?

    My area is Intrusion Detection System in Wireless sensor network..I want to simulate now. Which is the best simulator(either NS2 or NS3 or any other ....).sugesstion plz.

    Joseph Jude · Kongu Engineering College

    Install MannaSim Patch  in NS-2.29 Version  For sensor network in NS-2, It is easy prefer FEDORA-18 rather than ubuntu

    First you have to install NS-2.29 version

    then you have to add Mannasim Patch

    NS_3 is not a suitable candidate because of following reason

    LIMITED support only 15 support forum

    THE Sensor Simulation is not fully developed but it is there in NS-3 Package

    The steps are to be shown live but it can't described if you are really interested attend SEASON - 14

    we are going to have workshop in this regard, you get an in depth idea about ns-2 the details are follows

    National Level Workshop on Simulation and Emulation of Self Organized Networks-SEASON - 2014

    Hands on Session on NS-2



    Graph Generation and analysis

    Routing Implementation in NS -2
    Tcp Implementation in NS -2
    Rto Implementation in NS -2

    Registration Fee
    Faculty Members : Rs 2,000
    Research Scholar : Rs 2,000
    P.G Scholar : Rs 1,800
    Industry Delegates : Rs 5,000

    Important Dates
    Fest Date: 18- 09 - 2014 to 20- 09 - 2014
    Last date for application reception 15- 09- 2014

  • Tjandra Setiadi asked a question in BOD:
    Biological Treatment of Produced Water

    I have to treat produced water (TDS = 14,000 mg/L; COD = 440; BOD = 150). Is there any industrial scale for treating the similar wastewater biologically (or MBR)? 

  • Syedah Sadaf Zehra added an answer in LDA:
    What other methods can be used for the EMG signals classification and feature extraction other than LDA ?

    Currently I am working on EMG signals classification and feature extraction for the control of multifunction upper arm prosthesis. I want to know if there are any other methods other than Linear Discriminant Analysis that can show better outcome?

    Syedah Sadaf Zehra · Chinese Academy of Sciences

    Shiva I want to know if any of the other methods can give better results than LDA

  • Atena Eslami added an answer in Orchidaceae:
    Can anyone help identify this orchid?

    locality: Colombia, Nariño altitude 3000 m.

    Atena Eslami · Lorestan University

    Hi, I haven 't ever seen this species in Iran. are you sure these is from Orchidaceae family? i don 't see any assymetry in petals!

  • Is there a pedagogy that is purely inclusive?

    A totality of inclusive methodologies strategies, approaches values and attitudes towards teaching and learning facilitation.

    Franz Kasper Krönig · Cologne University of Applied Sciences

    Dear Tsediso, 

    for me the question is easier to focus when formulated negatively: Is there a pedagogy that is non-exclusive? "Non-exklusive" should not only refer to organizational and legal questions, e.g. who is admitted to what type of education under which conditions. For me the key point is rather the awareness for barriers with regard to all participants of educational settings. Virtually every pedagogic act bears an exklusive potential. Does a teacher reflect upon the barriers she or he builds while teaching? Is she or he able to detect barriers in all didactic, pedagogic, organizational ans social contexts? Is she or he willing to take responsibility for barriers? Is she or he prepared to deal with barriers for the sake of each child no matter what it "costs"? As a good example from this perspective I regard the work of Vivian Gussin Paley, though she does not really talk about the concepts. 



  • What's the common approach or way to measure or evalute the “direct electron transfer” in electrochemical biosensor?

    i have H2O2 biosensor (Nafion/HRP/TiO2 film/ITO substrate), and i want to measure and evaluate the direct electron transfer between the enzyme and the electrode.

  • Manuel Nepveu added an answer in Fluid Dynamics:
    Why are physicists concerned with velocity fields instead of position in fluid mechanics?
    Navier-Stokes equation describes the evolutionary law of fluid velocity. Essentially, it is a special form of Newton's second law. But why not position here? People don't care about trajectories of particles or what? I have seen Wikipedia explain some things but it lacked many details. For example, it says velocity makes more sense for a fluid. Then in what sense?
    Manuel Nepveu · TNO

    marco's answer is very colourful. Indeed, paths of fluidelements are not usually important (if so, you use so-called marke rparticles in your numerical computations to see where they are going). But you are generally interested in the state of change of bulk quantities at given locations, hence concepts as density, pressure and.....velocity are the ones you want to know. With or without Italian or Dutch soccer :-)

  • Ramazan LİVAOĞLU added an answer in ANSYS:
    Ansys - reinforced concrete column

    Anyone worked in Ansys with reinforced concrete. I need to calculate bearing capacity. Model was done in Autocad (3d). For results I need stress-strain diagram etc...

    Ramazan LİVAOĞLU · Uludag University

    use workbench. then you can import your model to the ansys.

  • How to explain the reaction between NaOH and aluminum hydroxide (Al2O3)

    Chemical reaction between NaOH and Al2O3

  • Archana Prakash asked a question in Minerals:
    How to identify Re-worked sediments

    if microfossils are not fully coated, and only very few are showing colour change, can we consider it as re-worked? if only mineral grains are there how could we decide whether it is re-worked? what are the other signs of sediments re-working?

  • Carbon coated grids for TEM characterization

    Hello everyone. Can anyone tell me  that what kind of  carbon coated grids should i use for TEM characterization of my samples which are nanocomposites of graphene-polyaniline-metal-oxide nanoparticles which are being suspended in organic solvents

  • Is it moral to grasp and acquire ideas and outlooks from author's papers and books but not citing him or her in your paper?

    If it is not, why some scholars do it. They even paraphrase some materials from papers without citation. I do not call it pure plagiarism, and will call it quasi-plagiarism or peer-thought-plagiarism. What are you opinions about the topic. 

    Behrouz Ahmadi-Nedushan · University of Yazd

    Plagiarism occurs when an author uses someone else's ideas and pretend they are his/her own.
    We must still reference ideas that are not our own even if we paraphrase the sentences/paragraphs.

  • Rajaram Krishnasamy asked a question in Darkness:
    What will happen if someone to be in darkness for 10 years?

    Physiological changes

  • Deo Rashmi added an answer in Downstream Process:
    Can we purify RNA sample showing 260/280 ratio of 1.77 and use it in real time PCR?

    although RNA had been isolated long before and preserved at -80 C, they showed stacked bands of 28s and 18s rRNAs in good concentration. but when quantified through spectrophotometer ratio of 260/280 nm came as 1.77. Now I am confused if they can be used in downstream processes where real time assay has to be done. Kindly provide your valuable suggestions in this regard.


    Deo Rashmi · University of Pune

    yes I have observed 2 clear and sharp bands of rRNAs on gel.

  • Is it possible for plants to express an inserted gene in pBI121 vector (without using Agrobacterium)?

    I need a transient assay of my gene in pBI121, but I don’t want to use Agrobacterium. On the other hand, can circular plasmids be expressed in plants? Can RNA polymerase II recognize 35S promoters in pBI121?

    Zahra Hajiahmadi · Isfahan University of Technology

    Hi Wan-jun,
    Thank you for your attention.
    Do you know which type of nanoparticles and nanocapsules can be used for gene transfer in plants? On the other hand,which type of polymers can be used to make nanocapsules  that can pass through cell wall and conjugate in plasma membrane?

  • What are the best methods for the sensory evaluation tests of baby foods products?

    A method for the sensory evaluation tests of baby food formulas

    Ass.Prof. Ashraf Mahdy Sharoba · Benha University

    THANKS  DR.Rosario S Sagum

  • Mobin Ebrahim Nejad added an answer in Sediments:
    Who can identify these sediments? Which sedimentary environment is appropriate for deposite of these sediments?

    This sediments belong to Sahand volcano (Tabriz, Azerbaijan) in the Late Miocene.Pliocene and are appear alternating with clastic sediments.

    Mobin Ebrahim Nejad · ........

    Hi all, Tanks for your comments

    There are many channel structures in this units specially in Lahar units.

    Whether these sediments were deposjted in the a lake environment under the influence of river ?

  • Marko Boban added an answer in Platelet Aggregation:
    What are mediators of platelets aggregation tests, and how do those correlate with clinical outcomes (MACE)?

    Resistance to antiplatelet drugs is frequently found in clinical practice, however clinical relationships are at the time being still mostly elusive

    Dear Chaojun Tang, thanks it is helpful, although I was thinking more on the factors that challange reproducibility of tests. As for instance diabetes is known to increase number of positive test results and those are not in straight forward correlation with increased prevalence of clincial endpoints as trhombotic event.

  • Atena Eslami added an answer in Arabia:
    What is the tallest Euphorbia species?

    I have found some samples of Euphorbia taifensis ( a new species discovered in Saudi Arabia, it was confused with Euphorbia ammak), this plant can exceed 10 meters of high, is it the tallest Euphorbia species of the world??

    Atena Eslami · Lorestan University


    Euphorbia milii (crown of thorns, Christ plant, Christ thorn) is a species of flowering plant in the spurge family Euphorbiaciae, native to Madagascar. The species name commemorates Baron Milius, once Governor of Réunion, who introduced the species to France in 1821. It is suspected that the species was introduced to the Middle East in ancient times, and legend associates it with the crown of thorns worn by Christ.

    these articles and sites will help you:




  • What is the assuming petrogenetic constraints of cold granite?

    Are all types of granites with temperature (based on zircon thermometry) less than 750 C are named cold granites?

    Mohamed Abdel-Moneim Mohamed · Assiut University

     Lot  thanks for you Mahar, and kindly ask you if you can send your paper to me

    e-mail:   m_moneim58@yahoo.com

  • Behin Sundara Raj added an answer in PDT:
    Can anyone help me in designing a safe method for UV light exposure(from lamp) to cell cultures?

    I need a safe procedure as it involves radiation. I am working on PDT, which involves UV light exposure to cell cultures. I need to know a safe, simple procedure to do the same. The source of light will be a portable lamp producing UV rays. What measures to be taken to confine it to a small place and what safety aspects should I undertake, when performing the experiment.

    Behin Sundara Raj · Curtin University Australia

    Hello Venkata reddy Bandugula thank you for your answer. Could you please give me some more specific details about the UV light chambers you have in your lab. A picture would be highly appreciated, followed by details where we can buy one.

  • Necdet Kocabiyik added an answer in Anatomy:
    Assessment of the size of the human omentum?
    Hi, Does anyone know of this Author and the availability of the published paper?
    Necdet Kocabiyik · Gulhane Military Medical Academy

    Unfortunately, I do not know. I did not study this realm before. But, I think the topic is interesting and meaningful.

  • How can I calculate ICC for a dichotomous dependent variable in a multi level analysis?

    I have a question on multilevel analysis. I hope I explain everything clearly, if not please let me know!
    I have a dichotomous dependent variable (burglary yes/no), which I try to explain by variables on three levels (house, street and neighbourhood). I am conducting multi level analysis. I just did some cross level interactions, which show a significant influence. With a normally distributed dependent variable, it is now possible to calculate the explained slope variance, to see how much percent of the effect is explained by this variable to see if the influence is indeed relevant. Since for a dichotomous dependent variable it is not useful to calculate the explained variance I used the ICC. But I cannot seem to find anything on how to calculate the ICC for the slope variance. Is this even possible? And if so, how do I do this?

    Marlijn P. Peeters · Ghent University

    A very late response, since other things came up this last month. I will dive into the literature you suggested and look into R more closely!

  • Rita Smirnov added an answer in Fish Culture:
    Is there any biological method to control water fluctuation in fish culture farms (especially salmonids) ?

    In many fish culture farm, sometimes we face water changes by means of pH, temperature, mineral contents that lead to several diseases and consequent economic losses. Is there any biological methods or any equipment that can concurrently detect water changes and response to this and balance the water. Directly I'm looking for articles and unfortunately I couldn't find any paper. 

    Rita Smirnov · Central Fish Health Laboratory,Nir David,Israel

    I think that the best literature on this theme is two books of Claude E.Boyd "Water quality managment for pond fish culture". They contain very useful and clear explainations.You'll find  many answers to your questions.