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  • Shen-Ming Chen added an answer in Metals:
    What is the work function of Raney Nickel?

    Has anyone measured the work function of Raney Nickel? I haven't been able to find it anywhere. I was wondering if the sharp points throughout reduce the work function as is seen when a metal surface is roughed up, or if its work function is approximately the same as regular Ni metal.

    Shen-Ming Chen

    Raney nickel is a fine-grained solid spongy nickel composed mostly of nickel derived from a nickel-aluminium alloy. Since Ni is the active metal of the catalyst, a large Ni surface area implies a large surface is available for reactions. Commercially available Raney nickel has an average Ni surface area of 100 m2 per gram of catalyst. A high catalytic activity and hydrogen is absorbed within the pores of the catalyst during activation, makes Raney nickel a useful catalyst for many hydrogenation reactions.

  • Refik Kanjhan added an answer in Aging:
    Who are the most competent, well written and respected researchers on aging?

    I am a research psychologist exploring the most cutting edge research on aging. Looking for researchers and writers who have ideas, theories or proven information on the topic. Thanks.

    Every good wish, -md

    Refik Kanjhan

    Dear Margret,

    My primary research interest is the motor systems.In my recent review I talk quite a bit about motor neuron aging and age-dependent elimination of fast-twicth motor units (see below. I have also attached for you the top most cited 50 research articles that had "aging" in their title. I am sure you will find lots of stimulating articles and authors who have significantly contributed to "aging research. Please contact me of you need any further information on that matter.

    Best wishes, Refik

    + 1 more attachment

  • Naveen Kalra added an answer in Land Use:
    Hello! Please I need to know how to estimate the Albedo and the emissivity for a urban area (a district)?

    I found in an article that they estimated the Albedo and the emissivity from the land use cover CORINE (carissimo,B.,Dupont,DE., Musson-Genon, L., Marchand, O., 1995. Note de principe du code Mercure version 3.1 EDF-DER, HE-3395007B.) but I can't find it. Thank's for your help.

    Naveen Kalra

    Dear Hajar

    you have to do beginning by trying yourself, i give you one link, which is very useful to explore your country/province




    thereafter i will give you another links

    within couple of days you will learn


  • Jainudeen K. A. Jameel added an answer in Gastric Surgery:
    Does the age >65 years influence surgical outcomes of patients submitted to total gastrectomy for gastric cancer?
    The age as comorbidity
    Jainudeen K. A. Jameel

    Age is not an independent risk factor for surgical outcomes, however in someone who is elderly and has significant co-morbidities, the benefits of doing a text-book type radical D2/D3 total gastrectomy should be weighed against the risks associated with increased operating time, post-op morbidity and mortality. Hence a less radical approach can be undertaken in selected elderly patients. 

  • Wei Wang added an answer in Plant Breeding:
    How to use potato processing factories by filtering protein, starch and fibre, processed water useful fertilizers?

    Now a day’s some plant of potato processing  are using waste as a fertilizers, disposed as the increased nitrogen, phosphorus and potassium contents, which are essential nutrients for tubers' growth, make it a suitable irrigation water.Anybody have experience of above. I know how to use that water?

    Wei Wang

    I have experienced  one way. They mixed the settled organic particles with the sludge, and then heated in a granulator.

  • Hengki Wijaya asked a question in Saccharomyces:
    This question about Saccharomyces cereviaseae strain baker yeast can be made bioethanol. I want to be reasearcher about this cases?

    This question about Saccharomyces cereviaseae strain baker yeast can be made bioethanol. I want to be inventor about this cases. Please to teach to make method and some literature about that? My studies is about making baker yeast with substrate palm water (Arrenga Pinnata). 

  • Kenneth M Towe added an answer in Iron Oxide:
    Can we prepared iron oxide nano particle/ any nano particle in acidic condition (pH around 4 ) ?

    In general, nano particle are prepared in basic condition. could any one suggest the procedure for preparation in acidic condition.

  • Nathan J Kenny added an answer in Bioinformatics:
    What is a good program to draw mitochondrial genomes?

    I am looking for a good and free to use program to draw circular mitochondrial genomes from a file (not genbank).

    thanks in advance

    Nathan J Kenny
    The above are good, and Ogdraw is quite pretty too. http://ogdraw.mpimp-golm.mpg.de/
  • Biswapriya Biswavas Misra added an answer in Sonification:
    How can I recover protein and resin?

    I'm trying to run a protein purification experiment using liquid chromatography. However, I forgot to remove DNA and other cellular debris from cell sonification before adding resin. What should I do to recover my protein with my resin?

  • Hengki Wijaya asked a question in Hyper:
    What do you think about "Hyper Grace" Book of Michael Brown,Ph.D? Do you agree about that? Please explaining to us?

    What do you think about "Hyper Grace" Book of Michael Brown,Ph.D? Do you agree about that? Please explaining to us? How about the view of your church about this situation?

  • Romuald Pawluczyk added an answer in Optics:
    I would like to know what are the best techniques to generate laguerre gaussian and hermite gaussian high order laser modes?
    Romuald Pawluczyk

    To be able to do this, first of all you need to remember, that higher order modes have higher divergence, therefore you need the laser with larger cross section of active  medium, than the lasers working in TEMoo mode. Next, the resonator should have low mode selectivity, which is contradicting the industry standard where a lot of ingenuity was invested to eliminate mode structure and to produce a light beam with intensity profile either Gaussian or flat hat.- as flat across the whole active medium cross section as possible. Old experimental He-Ne lasers with large internal bore diameter (7-10 mm), equipped with almost confocal resonator were ideal tools for such experiment as you wish to perform. Taking into account that strictly confocal resonator corresponds to a point where two instability regions cross two highly stable regions, the word  "almost" in previous sentence is very important: you should be in one of stability regions but quite close to confocal configuration. The simplest way to achieve this is to use two identical concave mirrors with very high reflectivity (.99%) with radius of curvature 5-10%  larger than planed length of the resonator. In ideal case such resonator generates axially symmetric, which by misalignment of resonator in two perpendicular directions could be transformed into modes with two axis symmetry. This  method works quite well for low order modes, and to obtain higher order you have additionally modify loses inside the rezonztorby introducing into resonator some obstacles, very thin  needles, for example.

  • Azzam K Almosallami added an answer in Theoretical Physics:
    Why in SR light has constant speed?

    Constancy of light speed in all inertial systems in SR is somehow hard to understand. Do we have some common explanation ?

    Azzam K Almosallami

    Dear Amrit,

    The speed of light is also unchanged by a rescaling x′ = Sx, y′ = Sy, z′ = Sz, t′ = St where S is any function of v. Combination of this with a Lorentz transformation gives x′ = SR(x − vt), y′ = Sy, z = Sz, t′ = SR(t −xv/c2). Choosing S = R we get:

    x'=R^2((x − vt), y′ = Ry, z' = Rz, t′ = R^2(t −xv/c2)

    Now according to this transformation you can compute the Sagnac effect according to t'-=R^2(t −xv/c2) and t'+=R^2(t +xv/c2), and from that we get

    delta (t)=t'-- t'+= R^2(xL/c2) by considering x=L. This is exactly the same result of computing Sagnac effect  in the framework of the ether theory. Also this transformation gives you real interpretation of H&k experiment.

    The rescaling violates “reciprocity”. Now according to this transformation the moving train is governed by the Schreodinger equation, and thus changing the velocity is related to radiation exchange and  that means transforming from quantum state to another quantum state. By the removing the reciprocity principle, the wave-particle duality and uncertainty principle appeared in macro world and also the entanglement. So all the quantum phenomena were hidden behind the reciprocity principle.

    According to that we can make all the calculations from Higgs to Galaxies and the calculations agree completely with this transformation.

    The main question here;

    What is the importance of the reciprocity principle????????

    The reciprocity principle is only to appear as the macro world moves according to objectivity and continuity....no more!!!! But quantum theory proved contrary of that. Because of that proponents of relativity hate quantum theory and the Copenhagen to describe the macro world. 

    I think a student in high school can now understand physics in very simple way.

    a wave equation for sound, e.g.
    where cS is the sound velocity in air and p is the pressure perturbation. Maxwell took the propagation velocity in as the velocity of light with respect to the ether that was perceived by him as a hypothetical medium in which light propagates like sound in air. And now according to our new transformation, the concept of acceleration is related to vacuum fluctuations which governed by Schroedinger equation, and from that the equivalence principle in gravity must be defined.

  • Shen-Ming Chen added an answer in Gravimetric Analysis:
    Why does adding HCl prevent co-precipitates (Ba(OH)2, Ba3(PO4)2, BaCO3) from forming? Hint: What do the anions of those compounds have in common?

    Question for a pre-lab of an experiment on Gravimetric Analysis for Sulfate

    Shen-Ming Chen

    BaCO3: 2HCl(aq)+BaCO3(s)=BaCl2(aq)+H2O(l)+CO2(g) 

    Ba(OH)2:  2HCl(aq)+Ba(OH)2(s)=BaCl2(aq)+2H2O(l)

    Ba3(PO4)2:  6HCl(aq)+Ba3(PO4)2(s)=3BaCl2(aq)+3H3PO4(aq)

    H2CO3  pKa1, pKa2

    H3PO4  pKa1, pKa2, pKa3

    H2SO4 pKa1, pKa2

    Ba(OH)2, Ba3(PO4)2, BaCO3  BaSO4 Ksp of four ppt

    You can understand why does adding HCl prevent co-precipitates (Ba(OH)2, Ba3(PO4)2, BaCO3) from forming and an experiment on gravimetric analysis for BaSO4.

  • Devendra Solanki added an answer in Identification:
    Can anyone identify these mollusk species?

    This is may a species from family Assiminidae!

    Help me to properly identify.

    + 1 more attachment

    Devendra Solanki

  • Rajesh Chaudhary added an answer in Diabetic Foot:
    Is there anyone using honey for the dressing of wounds? why aren't the people convinced about it's efficacy in wound healing?

    in  my clinical practice i've been using honey for the treatment of venous ulcers, bed sores, burns, necrotising fascitis, burst abdomen and even in case of diabetic foot too. i heve seen wonderful results. there is scarcity of data in terms of trials and most of the surgeons don't agree to accept it but is a good debriding agent.

    Rajesh Chaudhary

    In my clinical practice I have been using honey in diabetic patients too . and I has shown good results. Patients responded well . yes the RCTs are required to prove it beyond doubt.

  • Steven Sesselmann asked a question in Data Model:
    Where can I find raw data to model galaxy rotation curves?

    I am specifically looking for mass distribution and observed angular velocity of as many galaxies as possible.

  • Napoleon Ono Imaah added an answer in Behavioural Science:
    Is there an inflation of voting systems going on?

    It looks to me, as if votings in sciences, politics and here as well are done too easily.

    (Consumption attitude: "Votings light")

    You like an opinion or you dislike it and immediately there is a vote on this, even when the opinion is just a weak consent "yes" or dissent "no".

    But persons who take their time, to put in efforts and knowledge by explaining and communicating, they either get the same vote (if they are lucky) or less votes, as it is another effort to read it and think about it.

    So in the universities, institutions, governments and here the quantity seems to become of a bigger importance than the Quality??

    What do you think about this? How about this in your own field of work?

    Napoleon Ono Imaah

    I understand the inflation of voting as support to contributors'' comments, and I believe that support cannot be too much or too bad. What I do not understand is deflation by dumb downvotes; are downvotes mere denial of support or intolerance of views not supported or opposed by downvoters? Thus, downvoters should not just be 'trigger-happy, but they should make their reasons for downvotes open.

  • Timofey Golubev asked a question in PDMS:
    Is there any significant difference between the PMMA film made from PMMA dissolved in chlorobenzene and that from PMMA dissolved in dichloromethane?

    I am attempting to use the process described in the link below. Briefly, one spin-coats PMMA onto the substrate that has nanostructures on it. Then put PDMS on top and add a few drops of water which is supposed to allow the PMMA to separate from the substrate. Then use PDMS as mechanical support to transfer to clean substrate. My initial substrate is SiO2 with some tape residue remaining from mechanical exfoliation. I want to transfer to clean SiO2.

    I am unable get the PMMA to separate from the substrate as a film. It resembles more like a paint which I can only scratch off. I suspect something is wrong with the PMMA solution. I use 950k 2% in chlorobenzene, something we already have in our lab.  The paper uses 3% in dichloromethane, but I was told it will not make a difference. I have tried different PMMA spin rates (1000-3000rpm) and annealing temperatures (50-80C) with no success.

    Any advice will be much appreciated

  • Munazzam Ali Mahar asked a question in SPSS:
    How to plot factor scores extracted from a geochemical dataset and plot back on the map?

    I want to know how to plot factor scores extracted from a geochemical dataset and plot back on the map? For example map for Factor 1 etc... In SPSS I do not see any option where I can relate factor scores back to sample id or location



  • Jainudeen K. A. Jameel added an answer in Lung:
    Is there a role for pallaitive APER in patient with lung mets?

    48 yrs old gentleman diagnosed with low rectal tumor with threatened CRM with lung mets - resectable

    post long course CT RT  - primary responded but lung mets now inoperable

    underwent 3 months of palliative CT - excellent response to lung mets now multiple seen but all between 2 - 8 mm 

    pt has no symptoms from rectal tumor - what is role for palliative resection?

    Jainudeen K. A. Jameel

    Unless there are symptoms from the rectal tumour (bleeding, obstruction etc.), there is no role for resection, because by definition, this is metastatic and advanced disease. Even if the patient is symptomatic, I would be more in favour of something less morbid such as a loop defunctioning colostomy rather than a palliative APER.

  • Enwelum Mbadiwe added an answer in Permanent Magnets:
    Explain the reason why permanent magnet flux switching machine does not have outer PM rotor configuration (PM mounted on the rotor))

    It is due to very low field weakening status?

    Enwelum Mbadiwe

    Still investigating

  • Madhurima Saha added an answer in Proteins:
    Does anybody have studied the expression of GLUT4, Akt, AS160, AMPK or CaMK in PBMC?

    Does anybody have studied the expression of GLUT4, Akt, AS160, AMPK, CaMK or other proteins related to glucose uptake in mononuclear cells from humans?

  • Vishwanath Hiremath added an answer in Thin Films and Nanotechnology:
    How can I calculate the band gap from UV-Vis absorption spectra of thin films consisting of TiO2 and other metal complexes?
    I have prepared thin films of TiO2 and other Metal complex with TiO2 on a glass substrate. I just need to calculate band gaps of materials on the glass substrate.
    Vishwanath Hiremath

    @suchitrs sen ... The two peaks were observed in the plot of absorbance vs. Wavelength.

    However, when i plot for ahv vs hv the curve seeems smooth.

  • Soham Biswas added an answer in Semiconductor:
    How do I identify a semiconductor is n-type or p-type using Electron configuration?

    From Periodic table or from electronic configuration point of view

    Soham Biswas

    As we all know, an N-type semiconductor is the one that has been doped with a pentavalent element (that is, five valence electrons). This additional electron (silicon has four) shrinks the band gap by expanding the conduction band (the higher energy levels). Whereas P-type semiconductor is exactly the opposite: a semiconductor doped with a trivalent element (three valence electrons). This "donates holes" to the structure, and shrinks the band gap by expanding the valence band (lower energy levels).

    Now you can see this link for the difference of these two on the basis on electronic structure : https://www.quora.com/What-is-the-difference-between-N-type-and-P-type-semiconductor-materials

  • Behrouz Ahmadi-Nedushan added an answer in Educational Systems:
    How should / could we improve the Educational System, to adapt modern times, and future generations?

    Most would agree that Education plays a fundamental role in solving many of the humanity's current problems.

    I believe in a better World.

    Mass education for all youngster can play a good role in the near future.

    Should we change our system?

    Should we act on University level?

    Should we act transversally from kindergarten, through basic education?

    I should like your valuable contributes.

  • J. C. Biswas added an answer in Crop Production:
    Short- and long-term consequences of zero/minimum tillage on crops' productivity and soil environment?

    Zero- and minimum- tillage have been debated for mixed response, in intensive agriculture zero/minimum tillage is important from viewpoint of turn around time, debated for energy saving, enhanced water and nutrients use efficiency. Any review/experiences on this aspect may help in its faster adoption. your views please on this imp topic

    J. C. Biswas

    No debate about energy saving. Zero tillage/minimum tillage helps in carbon sequestration. However, weeds become serious pests sometimes. Adoption of this practice is existed in low lying areas where farmers just clean weeds and transplant rice seedlings. Moreover, soil texture and nature of crops dictates such practices.

  • Marković G. Đoko added an answer in Political Socialization:
    Who is a sycophant? Is sycophancy an Art?

    We see sycophants in all the fields - political, social, administrative ......

    Do you think it is an art that is harmless or something that harms the organisational culture severely.   

    What kind of sycophants are prevalent in your part of the world.

    Marković G. Đoko

     Real art is a form of protest against the incompleteness of life and futile reasons of existence, and there is no room for artist known as sycophants. Kitsch is a product of artist sycophants.

  • Guillermo Schinella added an answer in Spectrophotometer:
    How to determine anti inflammatory activity in extract by spectrophotometer?

    How to determine anti inflammatory activity in extract by spectrophotometer?

    Guillermo Schinella

    Can be assessed anti-inflammatory activity in vitro using cultured leukocytes evaluating different parameters using different spectrophotometric methods. You can observe them in the following citation:

    Góngora L, Giner RM, Máñez S, Recio MC, Schinella G, Ríos JL. Effects of caffeoyl conjugates of isoprenyl-hydroquinone glucoside and quinic acid on leukocyte function. Life Sci. 2002; 71 (25):2995-3004.

  • Thomas Fitzgibbon added an answer in Dendrites:
    Is this DiI staining valid or specific?

    I placed DiI crystals into the hilus of P10 mice horizontal sections (vibratome). I think the first image is from the CA3 region, and I can't tell if these are dendrites/axons or background, whereas the second image clearly has spines and does not belong near the CA3 region but is somewhere else in the cortex (can't tell right now where).

    + 1 more attachment

    Thomas Fitzgibbon

    just a note to add to Thomas Launey response...I used DiI and DiA together in fixed tissue, some formalin fixed some PFA, after placing the crystals in the tissue this was left at 30C  for variable amounts of time..fetal tissue always works better than adult and adult material that has been fixed fro some time in formalin gives variable results...as pointed out by Thomas the intergrety of the tissue is very important, any breaks in the membrane can lead to a lack of sufficient diffusion...there are several issues with formalin and PFA and there breakdown over time, a search on the effects of fixation is workwhile...also be aware of the health hazzards if you decide to use fixatives at higher temperatures.. there is also a DiI in an oil form i think which perhaps could be pressure injected..not sure if this works in fixed slices...

  • M. Kanagasabapathy added an answer in Electrochemical Kinetics:
    In electrochemical transient techniques for investigating the electrochemical kinetics which yields optimal result, Galvanostatic or Potentiostatic?

    In electrochemical transient analysis for investigating the electrochemical kinetics which yields optimal result, Galvanostatic or potentiostatic?

    M. Kanagasabapathy

    Thank you Dr. Chen for your prompt response. My point is which will be better? Chronopotentiometry or Chronoamperometry to analyse the electron transfer kinetics.