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  • Bulkesh Siwach asked a question in Particle Size:
    Can the particle sizes calculated from SEM, AFM and XRD must be same?

    But in my case it is not so WHY?

  • Zakir Khan asked a question in MPI:
    Can anyone give a suggestion me the good Journal for MPI and RMA paper submission?

    I need a good responding ISI indexed journal for my publications.

  • Bulkesh Siwach asked a question in Roughness:
    I have the roughness factor of 200nm in the TiO2 film as found from AFM? Is this film can be used in DSSC as photoanode?

    We require rough films as photoanode in DSSC. But what about this roughness value?

  • Muhammad Sohail asked a question in Load Balancing:
    Comparison of cloud computing (Load Balancing) algorithms in cloud Sim?

    I want to start my research in cloud computing (Load Balancing). How can I compare different algorithms in cloud Sim. 

  • Seyedeh Ghazal Ghalebandi asked a question in Research Methods:
    How would you rephrase this research objective?

    following is one of the research objectives in a qualitative case study research method - how would you rephrase it ?

    A) To understand children’s e-reading comprehension of reading apps

  • Srikanth Reddy added an answer in Smart Home:
    Is there any good topic on smart homes and buildings for a PHD research?

    I just entered the 1st year PHD research and need to figure out what direction to do in Smart Grid.

    I guess that home / buidling automation related might be promising using IoT approach.

    Does anyone have any good idea on home energy management?


    Srikanth Reddy

    It is always good to choose an evolving domain like Smart Grid for research. The home energy management has got a good diversity and scope to make things interesting and challenging which is the most essential part of research. You can link the energy management in home with one or more of following aspects. The home energy management (HEM) can be a potential aspect of following aspects.

    1. Of course the Demand side management strikes everyone's mind first when it comes to HEM. 

    2. Participation in Energy and reserve markets (modelling of demand response for the market participation)

    3. Energy efficiency 

    4. Green Building concepts for smart grid initiatives can employ the HEM

  • Francis Steven Mickus added an answer in Art:
    Do we need any definition of Art?

    I´am wondering if we need any kind of definition of Art. In the last period of time, the Fine Art lack any boundaries, or rather should I say any bounderies that couldn´t be falsified. For example if some artist make sincerely a piece of Art and react on something, and some years later, somebody else make something simmilar but inspired only by succes of the first artist and we recognise him, is the second artist also real artist and maker of Fine Art? So I think, there should be some ground rules, and we couldn´t just agree with everything. What I am trying to say, is that despite the overcome normativity in art there should be some rules.

    Francis Steven Mickus

    One seems to want to say that a definition says it all; but in fact it says nothing. That is always the case. We would be hard put to find a sigle sentence definition for the word 'blue' that covers all its usees and intended meanings. that does on the other hand preclude the usefulnees of having a definition for the word 'blue'

    A definition of art mere provides an intellectual form to the word that makes it a meaningful word, but no single sentence definition will cover all its acceptations.

    Your sentence about art does not cover all the meanings of art, nor should it, but it give the idea sufficient form for you to advance your arguments. But obviously, it doesn't cover everything, nor should it. a propoer definition for any word would require a fifty page article , and dictionnaries would be useless. indeed there are deifferent types of dictionnaries to cover different aspects of definition.

    The problems we face with definig art are the problems we face with definig anything. any definition will be limited and constricting. but it is necessary to come up with a shared definition so that we can communicate. To refuse to define, however incomplete that defintion can be, is to refuse to communicate. The converation becomes interesting when we appreciate the shades of meaning each of us brings to that defintion.

    Finally in the case of art, read the corellary questions and you will see the very need M. Makky is driving at. A practical definition would greatly help here, evven if the questions are answered in the negative.

    And yes, i agree with you is say thang that reducing a work to a taylorised commoditiy in which each unit is indistiguaishable from the next is a reduction of art. The artisitic instinct each and everyone of us has is to everything we can to individualize that object. But that is problem with our society and our art merely reflects our society. The art of an object is reduced to the creation of an elite. The rest of us are not allowed to think or act artistically.

    We must consume.

  • Claus Tieber added an answer in Arts Research:
    Which theatre practitioners or performance artists use archival material in their work?

    I am loking for artists who incorporate visual arts research into their theatre-making process. I am interested in the relationship between the document and the artist: What is it they are looking for? How do they approach these materials - as artefacts, as stimuli, as traces, as collaborators? I have a good understanding of the theoretical background to this debate and of the various innovations in performance documentation, but I want to learn about the ways archival material circulates in professional theatre as active tools.

    Claus Tieber


    Rimini Protokoll, a postdramatic theater group could be of interest

  • Bulkesh Siwach asked a question in Dyes:
    What method is most efficient for coating film to be used in DSSC application as photoanode?

    Large methods of depositing films are there but what will brought the highest efficiency and large dye adsorption? 

  • Soraya Rahimi asked a question in Nerve Fibers:
    Does the increase of myelinated nerve's length have an effect on increasing velocity of action potential propagation ?

    By causing the depolarization process to jump long intervals along the axis of the nerve fiber, this mechanism increases the velocity of nerve transmission in myelinated fibers as much as 5- to 50-fold.

  • sheik abbass Imthiaz asked a question in Weeds:
    How can I randomly distribute seed traps and is it necessary have the same size of the plot in two different areas?

    One of my objectives is to: Quantify and compare the seed rain of fleshy-fruited, bird-dispersed seeds under trees in weeded and non-weeded area.

    Am planning to use random number table to randomly distribute seed traps under trees in both areas.

    • Is there a better alternative to what am about to do.
    • Is it necessary have the same size of the plot in both weeded and non-weeded area. (because I got mix answers where some said it's not necessary and some said it's necessary)
  • Bulkesh Siwach asked a question in Graphene:
    Where should be the Graphene signal in XRD?

    I have coated tio2/graphene composite film on ITO by doctor blade and want to know how can I see its incorporation from XRD.

  • Dimitrios V. Peponis added an answer in Wave Propagation:
    How can be the maximum conductivity of a PML layer calculated in a waveguide?

    Consider a waveguide (cylindrical or rectangular) which is terminated with a CPML layer in both ends, perpendicular on z-axis. The CPML layer is characterized by sz conductivity value, which changes with the distance inside the layer. The value of the maximum conductivity is given by

    smax=-(m+1)lnR(0)/2nδ where m is the polynomial factor ,δ is the pml thickness and n the wave impedance in the medium.R(0) is the desired reflectivity of the layer.

    In a waveguide where certain mode propagates, the wave impedance is different than the host material. But in the literature, smax is only defined using the host material wave impedance. Should it be replaced by the mode wave impedance or this is a characteristic of a medium, ignoring the nature of the waves propagate inside?

    Dimitrios V. Peponis

    Dr Petropoulos and Dr Orobtchouk thank you for your answers.

  • Bulkesh Siwach asked a question in Solar Cells:
    Can we see open circuit voltage value from the Data recorded from simulator directly? Or we should see it from the IV plot?

    The Voc from the data and from the plot have very much different values in my case. The solar cell I am talking About is DSSC. So what value I should use in calculating efficiency?

  • Sekar Gopal added an answer in Perception:
    What is the difference between customer perception and customer expectation for a product or a service?

    On several occasions writers use customer perception and expectation interchangeably. Do we have existing literature distinguishing the two?

    Sekar Gopal

    Dear Gabriel,

    Since you are working in a bank, Ii will narrate an example about a bank incident for you to understand the CUSTOMER PERCEPTION & CUSTOMER EXPECTATION. I walked into my bank branch in my town in India with a PERCEPTION that, the bank will be crowded (Usually Indian Banks are like that) and I EXPECTED that i need to wait in a cue to complete my transaction and it may take couple of hours.

    Actually, what happened was, yes, the bank was crowded and upon seeing me walking inside the bank, the bank manager asked me, how shall he help and when I told that, I came for this transaction, he invited to his room and helped me complete the transaction within 15 minutes, which made me so happy and I became the loyal customer to the bank till date.

    Here, you can see clearly AS A CUSTOMER, WHAT MY PERCEPTION AND EXPECTATION WAS before I reached the bank and what happened there was my experience.


    Guess, this little input may be of help to you.

    Best Regards.

    Sekar Gopal.

  • Bojidarka B. Ivanova added an answer in Metal Complexes:
    What is the characterization used for finding oxidation state of Sn metal in complexes?

    i have synthesized organotin complexes and characterized by NMR, IR.

    Bojidarka B. Ivanova

    Mr. Paech,

    There is not nothing hidden, the example is even more than explicitly illustrative because of it is mono-nuclear complex of Sn.
    So, when you have conducted mass spectrometric (MS) experiments they can be carried out under positive or negative operation modes. The shown example in the previous posting is experimental ESI(+)-MS data (meaning positive operation mode). When you have this mode, then your MS spectrum contains observable cations, which can be monocations and polycationic forms. They are explicitly determined, too. Each cation has exact isotopic shape depending on the elemental composition. When you have given composition of a metal-organic complex and this composition corresponds to a cation like the shown example of Na+ adduct of [SnCl2], meaning cation of [(SnCl2)Na]+, then to ensure a balance of 1+ charge of this cation, means that Sn has +2 oxidation state. If we have proposed +4, for example, then the total charge should be +3 for [(SnCl2)Na]3+ trication. However m/z should not be at the shown value 212. It should be, if this happen, at m/z (212)/3. Despite the fact that there are not stabilized trications. Usually are observed dications, so that MS isotopic shape sould be at m/z = MW/2 for dications.

    Please pay attention to refs. [2-5], where have even more complex examples of di - and polynuclear complexes. In [Ref. 2] are shown dinuclear ZnII-containing organometallics, which ar enot so illustrative due to the stable oxidations tate of the ZnII - ion. But we have also example of cationic clusters of metal ions with unstable oxidation state such as Ag, Au, U, and more, where within the frame of a dinuclear positively charged Ag-complex, for example, with strictly fixed chemical content and structure, determined by MS/MS approach, there is possible to have a combination of following cations to each complex [X-AgIAgIII-Y]+, [X-AgIIAgII-Y]+, [XAgIIIAgI-Y]+, and s.o. They are characterized with different thermodynamic stability; or they are distinguishable as stability and chemical-physical properties. In our studied we have deduced oxidation state to each of metal ions employing quantum chemistry. In the cases of mixed metallic complexes (we have charged alloys compositios, too), the possible combination of oxidation states to each complex significantly increases in, along with a significant increasing in the structural isomers. The mean reason for this is that the metal ions in those complexes have different coordination environment, meaning different geometry of the metal chromophores. In this respect, the positive charge which is establish experimentally by MS (or doubly charge in dications) is not equally distributed over each metal ions in the given complex. This particularly is more illustrative shown in the case of composites [(M)nXYZ]+, [(M1)n(M2)mXYZ]+ [Ref. 4]. In this context there is possible to deduce the oxidation states of metal ion in polynucler mixed valence complexes (for example AuI/AuIII-, FeII/FeIII-containing complexes, like those in Refs. 4,5) as well as polynuclear mixed metallic and, in parallel, mixed valence complexes (for example AuIII/AgI -containing complexes).

    [Ref. 2] Silver(I) and zinc(II) organometallic intermediates, catalysing coupling reactions of polysubstituted benzoic acids - Experimental and theoretical study, Bojidarka Ivanova, Michael Spiteller, Chemical Engineering Journal, Volume 232, October 2013, Pages 118-127

    [Ref. 3] Organosilver(I/II) catalyzed C-N coupling reactions-phenazines, Bojidarka Ivanova, Michael Spiteller, Catal. Sci. Technol., 2013,3, 1129-1135

    [Ref. 4] Adsorption of uranium composites onto saltrock oxides - experimental and theoretical study, Journal of Environmental Radioactivity, 135, 2014, 75-83

    [Ref. 5] Study of sorption of uranium ions onto Fe-containing minerals using UV-MALDI-MS and theoretical quantum chemical modelling
    Bojidarka B. Ivanova, Michael Spiteller,Water Air and Soil Pollution 11/2014; DOI:10.1007/s11270-014-2208-2 (http://www.researchgate.net/publication/268211751_Study_of_sorption_of_uranium_ions_onto_Fe-containing_minerals_using_UV-MALDI-MS_and_theoretical_quantum_chemical_modelling)

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: This is the first report, devoted to quantum chemical modelling and solid–state mass spectrometric UV–MALDI–Orbitrap–MS study of sorption of uranium complexes Un+ (n  1–6), [UO2]2+, UO3, [UO2(OH)]+, [UO2(HO)2]0, UO2(OH)3]-, [UO2(CO3)]0, [UO2(CO3)2]2- and [UO2(CO3)3]4- onto Fe–containing minerals, discussing the surface interactions on goethite and ferriannite in thermodynamic terms. The content has involved: (i) pH ( 2–10) affects on the stability of uranium on surface modified centres FeOH, FeOH2+ and FeO-; (ii) Oxidation state of uranium ions and it thermodynamics affect; (iii) Oxidation state of Fe–centres, precipitation and redox reactions, governing the sorption behaviour of uranium, including it reduction to various low–soluble forms; (iv) Role of the ligands from the inner–coordination sphere of the uranium complexes on the surface interactions and; (v) Thermodynamics of 2E and 2C binding modes of [UO2]2+ on Goe and various interactions to equatorial O– and axial KxAlyFez–shells in Ferr. Despite the interdisciplinary significance, it has only few potentiometric studies in this topic, which can not explain in details the molecular level structural aspects of the surface bonding and numerous molecular factors causing for the environmental migration of uranium. The lack of that knowledge difficult the reliable modelling of sorption processes in the nature, and thus to understand comprehensively important biogeochemical reactions, governing the uranium bioavailability. Given that, our study has illustrated the great prospectives and applicability of the shown strategy for an achievement of meaningful thermodynamic information, also highlighting it high sensitivity toward molecular level interaction processes, including a strong differentiation between the oxidation states of the uranium. The results have provided reliable explanation, too, of already known facts for the behaviour of uranium on colloidal matter, accounting for it competitive coordination ability in the presence of organic ligands under real environmental conditions.
      Water Air and Soil Pollution 11/2014; DOI:10.1007/s11270-014-2208-2
  • Jose Ignacio Rojas Gregorio added an answer in Aerospace Engineering:
    Why is gradient correction not required for calculating the runway length for landing case?

    While determining the runway length for take off case, correction for elevation , temperature & gradient are made. But for landing case corrections for elevation & temperature is made. Why correction of gradient is not required.

    Jose Ignacio Rojas Gregorio

    Dear Lohit,

    It is true that in the A320 manual there is no correction for gradient/slope of the runway for landing. The explanation may be the following, as found in the manual in 2.03.10 P2:

    - "For most cases of abnormal landing configuration, the increased landing distance does not exceed the required runway length for landing in normal configuration. However, the addition of several of these factors can very quickly lead to an overrun. Special notice should be taken of the runway conditions. A slippery runway is the most common reason for overrun at landing. The combination of a slippery runway and a factor such as tailwind or an increase in approach speed should be avoided. [...]".

    The distance that you can read in the tables assumes that the aircraft stops completely in the runway (reduces speed down to 0 m/s) and no turbofan reverse thrust is used. Moreover, the available distance for landing (LDA) must be assumed that is only around 60% and the landing distance increases 1.15 times if the runway is wet. A colleague thinks that, given that there are so many margins, and the gradient is usually small, its effect can likely be neglected, particularly if compared with using or not the turbofan reverse thrust. It may happen that, conversely, for take-off, when you must accelerate a large mass (TOW), the gradient plays a more important role. Remember that the take-off distances are always much larger than landing distances.

    This is all for A320. We don’t know if, for a smaller aircraft like the ATR, these factors have a greater or smaller influence.

    Hope this is useful,

    Jose Rojas

  • Bulkesh Siwach asked a question in Calculations:
    Value of FF(fill factor) of DSSC is greater than 1. What does it mean?

    I have made calculations and found FF>1. is it right or i have made some mistakes in calculations?

  • Ankit Gupta asked a question in Lysis Buffer:
    Sarcosine concentration for protein solubilization?

    we have solubilized recombinant protein with .3% sarcosine in lysis buffer and subsequently reduce it up to 0% in wash buffers, finally elute proteins in No sarcosine buffer. what is the effect of sarcosine concentration on protein activity? what is the maximum concentration of sarcosine will be used in solubilization, that protein remain functional.

  • Jayant Dewangan added an answer in Fractionation:
    What is the method to collect fractions after sucrose density gradient ultracentrifugation without using any fractionation system?

    I am trying to isolate polysomes using sucrose density gradient system from cancer cell line. I have to collect 13 different fractions after centrifuge but we don't have any fractionation system to collect these fractions. 

      Have any alternate options to collect different fraction.....please tell me 

    Jayant Dewangan

    use sucrose density gradient and for recovery of your sample Use a needle to puncture tube 3-5 mm above your desired organelle, and let the medium flow out of the tube.

    read following article for more details about different organelle fractionation.

  • Shilpy Agrawal asked a question in VANET:
    Is it possible to create vehicular ad hoc networks in MATLAB? If yes , then kindly guide me how?

    How to implement VANETs in MATLAB? 

  • sanjay mohan Sharma asked a question in Oxidation:
    Tribology of self lubricating composites

    I am working on tribolgical study of sintered iron based composites with certain reinforcements in different percentages and am facing a difficulty while going for high temperature wear testing. Since the base matrix is same and it is a comparitive study, kindly help me out in the problem of oxidation as how to tackle the problem of oxidation of composites at 500 degree celcius since I dont have any inert atmosphere

  • D.K. Pathak asked a question in Laptop:
    Can we configure a laptop or desktop to work as an AP using opensource firmware like openwrt?
  • Bulkesh Siwach asked a question in Casting:
    I have negative value of open circuit voltage in IV measurement data of DSSC? What is the meaning of negative Voc?

    The cell (DSSC) has Tio2 as photoanode and Drop casting Pt counter electrode.

  • Vignesh Umapathi asked a question in Protein-Protein Interaction:
    Hi! How to identify the interacted amino acid sequences in Protein - Protein Interaction for the purpose visualization as a network?

    Biological Data mining. How to extract the interacted amino acid sequences?

  • Manuel Morales added an answer in Art and Science:
    How to bridge Art with Science and Mathematics in the undergraduate studies?
    There are many efforts that are being done pertaining to this but it should be more effortless. The students of science and mathematics should be introduced to the importance of art and design in their education.
    Manuel Morales

    I have the perfect project for those interested.

    Although my invite to "Search For First Cause" are initially focused towards grade school children, graduates, and post-graduates, I invite my colleagues here at RG to feel free to participate as well (see links).

    As a Nobel Laureate told me in regards to inviting the public to help science correct itself... see "Flawed Scientific Method".

    + 1 more attachment

  • Manuel Morales added an answer in Science Education:
    What ways have you found to be effective to deal with students' misconceptions in science?
    My students learn biology and other sciences in English. Recently they had the Mid-semester test. Two of my 90 students had an F grade.

    When I checked their answers I found they had many misconceptions. Even simple questions like formation of a dipeptide; simple structure of a nucleotide were wrongly answered. The students admitted that they studied at the last minute.

    Any suggestions how to help such students with their misconceptions/confusions? In my time, my teachers would have told me to study till I can remember everything, understand everything and it all becomes crystal clear!
    Manuel Morales

    "What ways have you found to be effective to deal with students' misconceptions in science?"

    Truth. From there it gets interesting.

    + 1 more attachment

  • Mikhail Pylnev added an answer in Nanoparticle Research:
    How do you distinguish the reflectance of a TiO2 thin film from the reflectance of the Si substrate?

    I am trying to get the absorbance of TiO2 thin film applying Kubelka- Munk function to the reflectance spectrum however reflectance of Si is high in the UV-VIS region of spectra(200-500nm) and substrate is always thicker than the film(the thickness of the films are ~0.5-1.5 um).

    So, may you please recommend a paper/textbook in which this issue was solved? Is it possible to separate the reflectance of the film from the substrate in this case or it is better to use another substrate?

    Mikhail Pylnev

    Dear Karar,

    You should specify your answer.

  • Bulkesh Siwach asked a question in Simulators:
    How to calculate maximum power from the IV data of DSSC taken from Simulator?

    I have made measurements from Voltage= -1 to +1 and then recorded the current. My currents has ranges from milli to micro.