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  • Mahmoud Omid added an answer in Discovery:
    What is the greatest Discovery Ever ?

    I pay my respect to the Inventor in very destant past, who discovered the Wheel. 

    Other RG participants can have different opinion. 

    Mahmoud Omid · University of Tehran

    Dear Jestin is right. Sometimes it is useful to know how large your zero is.

    P.S.: Remember what Nathanael West said: "Numbers constitute the only universal language." 

  • Why electrons diffuse through only thin films ?

    It is known that in Transmission electron microscope, the electrons are diffuse through films less than 300 nm.  However, Scanning electron microscope coupled with Electron diffraction X-ray analysis, it is not diffused through  the sample.  So we can get only the surface elemental composition.  Why is it so.  Is the energy of electrons are not sufficient to pass through the thick samples.

  • Can anyone tell me in what respect legendre polynomial is better than chebeyshev , while using for polynomial approximation?

    Can anyone tell me in what respect legendre polynomial is better than chebeyshev , while using for polynomial approximation?

    Vaishali Sharma · BITS Pilani, K K Birla Goa

    no sir my area of research is singular integral equation, there i am using.

  • Kamal Hadad asked a question in Dosimetry:
    What are the errors in TLD dosimetry and two identical TLD dosimetry results be different?

    We performed TLD dosimetry of lungs of a RANDU phantom with Cs-137 source to compare with numerical results of EGSnrc MC code.  The results were 3-20% different. 

    For second time we performed TLD dosimetry, presumably with the same condition as first, however the the doses in right lung was higher and left lung was lower.  What could be the sources of such difference

  • R.C. Chhipa added an answer in Copper:
    Can someone explain how aqueous Copper(II) exhibits SP and moved to TBP?

    That depends on the electronegativity of Ligabdsd.

    R.C. Chhipa · Suresh Gyan Vihar Univeristy, Jaipur

    Ke Lin

    These are 

    Square Planar 

    Trigonal Bipyramidal

  • Energy conservation feedback?


    Hope you are well.
    I am writing a journal paper on spreading energy conservation awareness using the power of social networking.

    I would really appreciate if you could spare a minute to fill a survey for my research. This is crucial for completion of my paper and hence I have included only few important questions which shouldn’t take more than a minute to complete.

    Please follow the link to the survey:
    SURVEY URL: https://www.surveymonkey.com/s/8LYRG5M

    I would be great if you can forward it to your office colleagues and friends too as this would be of immense help to me and all individual responses will be kept confidential.

    Hope to receive a positive response from you. Thanks in advance!!
    Wish you a Merry Christmas and a Happy New Year!
    Amruta Nayak
    MS in Industrial Engineering
    University at Buffalo, the State University of New York

    A. R. Karbassi · University of Tehran

    I have completed the question form. However I believe that the questions should have been arranged in percentage wise than figures. 

    All the best

  • Pratama Jujur Wibawa added an answer in Band Gap:
    What is the relationship between a material color and its band-gap? How can we estimate the band-gap by color?

    What is the relationship between a material color and its band-gap? How can we estimate band-gap by color?

    Pratama Jujur Wibawa · Universitas Diponegoro

    I assumed you mean is solid material as commonly anyone said "material" it means solid material. Color of solid material is definitely determined by chemical composition and molecular structure constructed the material. Materials that are constructed by chromophore and auxochrome group-contained molecules will commonly generate color of visible light spectrum. It is because orbital energy level of valence electrons of a central atom of the groups (commonly hybridized s, p and d orbital) is equivalent to photonic energy of the visible light spectrum. As the consequence, this visible light photons will be absorbed by the valence electrons orbital’s and promote them from ground state energy to the exited state energy when the light strike the material. The difference energy between ground state and exited state is identified as energy band gap that has energy as high as the visible light wave length absorbed. However, electrons valence of exited orbital will not stable so that they move down to original ground state orbital by emitting visible light with certain wave length. This emitted visible light will be interference with absorbed visible light and provide color in our eyes perception. However the color percept by our eyes is not color absorbed by the associated material. In relation to that, the wheel color model of RGB or CYM proposed by Blauch (2009) can be used to predict the color percept by our eyes. Accordingly, in my opinion, you can predict energy gap generated between ground state and exited orbital of the associated molecules constructed your material based on the color absorbed. The way is, firstly please correlate the wave length of visible light with color absorbed on the material based on the wheel color model of RGB (red, green, blue) or CYM (cyan, yellow, magenta). From the correlation you can determined the color absorbed by the material so that you know the wavelength of the color. Using De Broglie formula, E = hc/wave length  you can calculate approximately the energy band gap of the material you mean as E.

  • Krishnan Umachandran added an answer in Tea:
    What are the medicinal benefits of lemon tea?

    Some excerpts from the article: "Medicinal benefits of lemon tea" by Mala Srivastava:

    "Tea is a good calorie-free substitute for sugary beverages, according to the Harvard School of Public Health. If you add a squirt of lemon juice to your tea, it will not only enhance its flavor but will also provide multiple health benefits. For example, if you are experiencing nasal congestion, drinking lemon tea can help to decongest your blocked nose, reports the University Health Service of Rochester University.

    Vitamin C Benefits

    One fluid ounce of lemon juice contains 12 milligrams of vitamin C. Water-soluble, vitamin C helps fight free radicals -- rogue molecules that damage your DNA. Free radicals may contribute to the development of diseases such as cancer and heart disease, notes University of Maryland Medical Center. By counteracting the negative effects of free radicals, vitamin C helps decrease the risk of developing cataracts by 80 percent, according to the book "The Secret Benefits of Lemon and Honey: Secret Guides.” In addition to healing wounds, vitamin C helps maintain and repair your teeth and bones. Moreover, your body requires this antioxidant to form collagen, a protein used to build skin, blood vessels, cartilage and tendons.
    Bioflavonoid Quercetin

    Citrus fruits, such as lemon, are one of the primary dietary sources of quercetin. A flavonoid, quercetin protects the insulin-producing cells in the pancreas from the damaging effects of free radicals. In addition, quercetin has an anti-inflammatory effect, as it helps stabilize the cells that release histamine in your body. Histamines are chemicals that trigger allergic reactions. According to the American Cancer Society, quercetin can inhibit the growth of cancer cells and can help promote apoptosis, a type of cell death. Animal studies have shown that quercetin may exhibit a protective effect against certain types of cancer, especially colon cancer.

    Blood Sugar Control

    High blood sugar occurs when your body produces inadequate amounts of insulin or when it cannot utilize insulin properly. Hesperidin, a compound in lemons, can modify the function of enzymes that affect your blood sugar levels, according to a study published in the January 2010 issue of the “Journal of Clinical Biochemistry and Nutrition.” This not only shields your body from the early stages of diabetes but also helps avert diabetes complications if you already have high blood sugar. Additionally, hesperidin has cholesterol-lowering effects.
    Powerful Limonoids

    A study published in the “Journal of Nutrition” in April 2005 revealed that lemons contain compounds called limonoids that have the potential to impede the growth and development of cancer cells. Not only did limonoids decelerate the growth rate of cancer cells, but they also enhanced cancer cell death when tested against human cancer cells. The study further states that these anti-cancer agents have free-radical scavenging activities."

    Your views are welcome! Thank you - Sundar

    Krishnan Umachandran · Professor

    Please dont take it as raw (Kashaayam), initially it would be very hard to taste.

    Again, on dark lemon tea, with a spoon of sugar will be a great energy booster.

  • Where to find real data on decision making in natural disasters?

    I would like to model and to solve real scenarios related to natural disasters (e.g. floods, hurricanes), specially in the relief phase.

    Shahab Shamshirband · University of Malaya

    Dear Pavel,

    May I know which model do you want to apply? 

  • sunil sharma added an answer in SDS-PAGE:
    Running two SDS-PAGE in the same tank. One is running normally, the other is not. Any ideas?

    Both the gels have 5% stacking and 10% resolving. They are essentially copies of each other and they even have the samples. One of them is running while the other is not. I'm running them at 200V.

  • Najeeb Ullah added an answer in Cotton:
    Is there anyone working on lintless cotton mutants?

    Is there anyone who is working on lintless mutants and ethylene production in cotton ?

    Najeeb Ullah · Pakistan Agricultural Research Council

    Thanks Vrinda Thaker, Did you study phyto-hormones in growing plants under normal conditions? which plant part? any variation in the concentrations of these phyto-hormones in normal and lintless mutants. I am currently working on lintless mutants and observed no variation in ethylene production from different plant tissues of lintless and normal plants, although some data indicated lintless mutants are not producing any ethylene. 

  • Kamal Hadad added an answer in Nanofluids:
    Any information on large scale industrial use of nanofluids as a coolant?

    Power plants have lot of water requirements. With limited water resources available more efficient cooling systems using nanofluids can save lot of water. This can reduce heat exchanger size and footprint also.

    Kamal Hadad · Shiraz University

    Numerous experimental and numerical studies have been carried out for applications of nanofluids in LWR nuclear reactors one of which is the link :

    Hadad, K., Rahimian, A., & Nematollahi, M. R. (2013). Numerical study of single and two-phase models of water/Al< sub> 2</sub> O< sub> 3</sub> nanofluid turbulent forced convection flow in VVER-1000 nuclear reactor. Annals of Nuclear Energy, 60, 287-294.

  • Zahra Lotfollahi asked a question in Ferrofluids:
    Is it possible a sample did not obey Williamson-Hall formula(XRD) or it is general?

    for example:magnetite ferrofluids

  • Kamal Hadad added an answer in Nuclear Engineering:
    What should be the maximum rate of positive reactivity insertion in PHWRs and how it is fixed?

    I have some of the doubts regarding reactivity insertion and removal rates.

    1. What should be the maximum positive reactivity insertion rate by each of the reactivity device in a PHWR?
    2. On what basis these reactivity insertion rates are defined of each of the reactivity device?
    3. What provisions / Systems are provided to take care of these reactivity rates?
    4. What should be the time constant (Time to reduce the poison concentration by the factor of 2) for poison removal from the moderator and why?

    Kamal Hadad · Shiraz University

    have a look at the link which describes reactivity controls in TAPP-4 PHWR reator.


  • Traian Iliescu added an answer in Perovskites:
    How can I evaluate a Raman mode (386cm-1) for LaInO3 at 386cm-1 is symmetric or antisymmetric stretching vibration?

    I have synthesized Ca-doped LaInO3 system. From the Raman analysis, I found the highest intensity peak at 386cm-1 which is due to In-O-In streching mode. How can I know that it is a symmetric or antisymmetric strecthing vibration?

    Traian Iliescu · Babeş-Bolyai University

    As you know in this region Bozon peack is located. This band  can be assigned to this tipe of  band? You can verify that.

  • Which model should I use when analysing the impact of food prices on food security in developing nation?

    I need to analyse the impact of food prices on food security. Which model to use? What variables to include? How to measure food security?

    Mohammad Reza Pakravan · University of Tehran

    Hi. you can receive to your aim by demand function analysis and elasticity derivation. so, you have one factor for food security, i recommend, Based on the study of Zhihao ZHENG and Shida Rastegari HENNEBERRY, You can use the energy Intake (calorie) as an indicator of food security. Then you need to calculate your nutrition elasticity. Finally, you can check the price effect on food security.

    Good luck

  • Mateen Hafiz added an answer in Marine Sediments:
    Can anybody uggest some reference papers on geochemistry of marine sediments from southern Bay of Bengal ?

    In search of literature available on rare earth elements and trace elements of deep sea cores from the Northern Indian Ocean

    Mateen Hafiz · University of Jammu

    Kindly see the following links regarding the geochemistry of marine sediments in Bay of Bengal 

  • Zafer Hawash asked a question in Nickel:
    How to make good NiO film by e-beam using Ni powder (for solar cells application)?

    I have Nickel powder and an e-beam deposition system, but after evaporation of Nickel, when i check XPS for Nickle i see elemental Nickel peak and Nickle Oxide peak, any suggestions on the evaporation method or any other easy method to get cotrolled NiO film without elemental Nickel?

  • Gulnaz Bashir asked a question in Filamentous Fungi:
    Can anybody provide me a reference for speciation of filamentous fungi?

    I want a reference on speciation of fungi especially zygomycetes.

  • Gulnaz Bashir asked a question in Sodium Hydroxide:
    Many AFB positive urine samples fail to grow on culture. What can be the reason behind this?

    Many urine samples which are positive for AFB ( acid and alcohol fast) fail to grow on culture in our laboratory in liquid as well as solid media. We are decontaminating the samples with 2% sodium hydroxide.

  • Yousef Hedayati added an answer in Damping:
    How many ways are there to determine damping ratio by the force vibration?

    and can anyone suggest some papers about that?

    Yousef Hedayati · Iran University of Science and Technology

    You can compute the auto correlation function from the modal coordinate signal. You will get a free decaying response. By simply using a curve fitting technique you can estimate the damping ratio.

  • Rawan A El-Madhoun added an answer in PCR:
    What are the causes of faint PCR product ?

    I  optimized my PCR Reaction and it gave me very good result , after that some  PCR product samples start to appear very faint in comparison with the other samples and the product of the first reactions i did !!

    Does I have to change the PCR condition or it is a problem of the quality of DNA used  ??

    Rawan A El-Madhoun · Jordan University of Science and Technology

    many thanks for your answer , 

    Yuan-Yeu Yau .. I use promega kit and I store the samples at -20 C .

    Ravi Pottathil ·no primer dimer appear with my result .

    Mahmoud El-Hindi · i decrease the anneling temp. twice they give bands in most samples but its look very very faint 

    Hamzah Abdulrahman Salman I am working in Humans DNA samples , by the way the same condition used for another human sample and give very good result 

    about the quality of DNA samples , I use the same samples with other SNP and it give me clear bands as appear in the upper line of the attached photo in comparison to the lower line which i faced the problem in . 

  • What is the logical connection between efficiency, competitiveness and market performance in agricultural production?

    I just need it for idea sharing and research purpose.

  • Himanshu Kumar asked a question in Ammonia:
    The total nitrogen incorporates organic and inorganic nitrogen ?

    With the help of spectrophotometric method, i have determined total nitrogen, nitrate and ammonia value are 17,15 and 14 ppm respectively, my question is how come it is possible if  the concentration of nitrate and ammonia will be added up, then the concentration of total nitrogen would be approximately 30 ppm but i am getting only 17ppm.....

    Why is it so?

  • Adity Saxena asked a question in Acting Theory:
    How to relate the "Speech act Theory" in emoticons analysis?

    I am a Phd student from India, my topic is the "Role of emoticons in message interpretation in computer mediated communication: A study of youth using Facebook in Delhi region". I am considering Speech act Theory for my theoretical framework.

  • Ahmed Ameen asked a question in Wheat:
    How can do artificial inoculation to wheat by smut disease?

    How can do artificial infection to wheat by loose smut  Ustilago tritici disease and when

  • Dipendra Gautam added an answer in Amplification:
    How does soil amplification factor relate the building damage pattern?

    What is the global experience of building damage with regard to soil amplification?

    Dipendra Gautam · Nepal Engineering College

    Thank you Behrouz!

  • Mohd Abul Kalam added an answer in PLGA:
    Can someone help me in preparing nano-particles for water insoluble drug using W/O emulsion method?

    My polymer is PLGA (65:35) and dichloromethane is the organic solvent, I am using 1% PVA as stabiliser and probe-sonicator to prepare the emulsion. After I prepare the emulsion I stirred the sample for 8 hours however the solution is still milky!!!! is this normal!!!! there is no smell for the organic solvent but I am worry from the appearance of the final solution, any suggestion?  

    Mohd Abul Kalam · King Saud University

    That means it needs washing with deioniezd water of the obtained formulation to remove the surfactant completely. Process: Keep the obtained preparation for ultracentrifugation at high speed (30,000 rpm for) for 20 minutes. Remove the supernatant, add water in to the obtained pellets, vortex it and centrifuge it again at the same condition.

  • Mohd Abul Kalam added an answer in Sterilization:
    What is the proper way to sterilize polymeric microparticles prepared for ocular drug delivery?

    I've experimented sterilization with autoclave, but the melting point of used polymer polycaprolactone is 60 ° C and so it is not suitable for my formula...and so on sterilization with filtration because I have microparticles.

    gamma radiation?

    Mohd Abul Kalam · King Saud University

    These can be sterilized by filtration sterilization technique if you wish to get particle sizes less than 220 nm