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  • Narayanan Nair Mohanan added an answer in Plant Identification:
    Please identify this species?

    Please help me in identification of this species. 


    Narayanan Nair Mohanan · Jawaharlal Nehru Tropical Botanic Garden and Research Institute

    This is Cuscuta  only

  • Nuzhath Khatoon asked a question in Movies:
    Why people watch movies? Is it personality of an individual is responsible for what type of movie he/she is watching.?

    I am doing a research on perception/ motives behind watching movies. what types of attributes people prefer to watch and how it is linked with their personality.I appreciate your views regarding this topic.

  • Sumit Dhawane added an answer in IgA:
    I need to create my Langmuir isotherm. Can anybody help me please?

    I need to create my Langmuir isotherm but i don't know how to calculate or where to find the Langmuir constant. I constructed my isotherm with the IGA instrument but i need to see if is a Langmuir isotherm or not. Any suggestion on how I could do so? Can anybody help me please?

    Sumit Dhawane · National Institute of Technology, Durgapur

    The langmuir adsorption isotherm can be plotted from the values of equilibrium concentration (Ce) and equilibrium adsorption capacity (qe). linearise the langmuir equation plot Ce/qe Vs Ce from the linear plot use the straight line equation y=mx+c, then from slope you will get 1/qm calculate value of qm then from intercept you will get 1/b*qm put value qm you will get value of b. these b and qm are the langmuir parameters, qe and Ce should be estimated from the experiments. 

  • Liseli Mulala added an answer in Language:
    ¿Por qué los hispanoparlantes que utilizamos research gate no hacemos preguntas y nos comunicamos en nuestra lengua materna?

    Los profesionales que hablamos castellano deberiamos comunicarnos y hacer preguntas también aquí en nuestra lengua y promover nuestro idioma que se habla en dos continentes. ¿Qué opinan?

    Liseli Mulala · Walden University

    Pienso que dependeria de la pregunta que uno va hacer o el articulo que uno esta publicando, si quieres que nada mas los hispanoparlantes contesten a la pregunta hazlo en espanol. But as our Portuguese  colleague has very clearly explained this will limit the responses and interactions you will receive.  Yo pienso que uno pueden comunicarse en espanol o en ingles dependiendo de  su meta. No creo que seria mala idea de usar todos los idiomas que uno habla teniendo en cuenta que haveces uno se esta limitando.

  • Massih Afghah added an answer in Structural Geology:
    What the different between the orientation and the trend of fault ?

    structure geology  

    Massih Afghah · Islamic Azad University Shiraz branch

    Dear Mohamed

    orientation means the direction of vertical and horizontal axes of the fault plane. A plane is defined by two perpendicular lines, called the strike (horizontal orientation) and the dip (vertical orientation). Actually A fault could be oriented NW-SE (or perhaps east 30 degrees south or similar) with a steep dip (say, 80 degrees toward the northeast), or it could be oriented east-west with a shallow dip (say 15 degrees south) whereas the direction of fault on surface with magnetic or geographical of north (strike) means direction of fault. you can see link below:

    link 1: https://www.uwgb.edu/dutchs/structge/sl35.htm

    link 2: https://books.google.com/books?id=nZI5AAAAIAAJ&pg=PA552&lpg=PA552&dq=fault+trend+definition&source=bl&ots=95Ur7qBlZz&sig=JG99XTR0FEPxi4zKxXeXTXlJSLw&hl=en&sa=X&ved=0CC4Q6AEwBDgKahUKEwjZ-fmwgMvHAhXIVRQKHdnCDxE#v=onepage&q=fault%20trend%20definition&f=false

    link 3: http://ocw.mit.edu/courses/earth-atmospheric-and-planetary-sciences/12-510-introduction-to-seismology-spring-2010/lecture-notes/lec18.pdf



  • Bholu Kumar added an answer in CFD Simulation:
    How might oone fix the boundary condition with pressure inlet and pressure outlet bcs at inlet and outlet in CFD simulation?

    In CFD simulation of airflow from human airways with the cases of inhalation exhalation, how to fixed the boundary condition with Pressure inlet and pressure outlet ? In my case pressure is changing with small amount for both cases of inhalation and exhalation which is not suppose to vary. Please someone help me.

    Bholu Kumar · Motilal Nehru National Institute of Technology

    Dear Abdul Sir,

    First of all thanx a lot. I am totally satisfy with your answer.  But when I am comparing my inhalation results with exhalation, I found there is about 4-5% of changes. The amount of volume inhale must be equal to the amount of volume exhale. I thought because of this change it is happening. Sir I am totally agree with your answer but whether we can fixed pressure or not ? 

  • Victoria Blue added an answer in Student Assessment:
    Kindergarten & primary school maths; how often should we test students in order to determine their level of competence?

    In order to make reliable judgements of a student's mathematical competence, how often and over how many years should  the student be assessed?

    Victoria Blue · Northern Arizona University

    Thank you, Magdalena.  The PreK information is embedded within the list of Texas agencies, organizations, etc.

  • Athiraja Atheeswaran asked a question in ACO:
    How to use ACO optimization technique in image retrieval?

    Dear friends I have completed GA optimization technique image retrieval . now i am doing ACO  optimization technique for image retrieval

  • Chandan S Chanotiya added an answer in GC-FID:
    Could anyone share their experience about developing a GC-FID method  for detecting Methanol in water?

    Column, inlet, internal standard, parameters...

    Thank you!

    Chandan S Chanotiya · Central Institute of Medicinal and Aromatic Plants

    Hello Dejan,

    Michael has rightly mentioned the requirement of methanol analysis in aHead-space GC coupled with FID. Further, BAC-1 and BAC-2 columns are best choice in detecting impurities in solvents. Column brands shall depend on the availability in your country. The thick stationary phases of  >1 micronmetre are recommended because  solvents have higher volatility or vapour pressure. Hence, stationary phase thickness shall be an important parameter here.

    The transfer of vapours from HS device into GC system is also equally important. There has been three sample transfer techniques available so far i.e.,

    i) Gas syringe type;

    It operates by thermosetting the sample in the oven at a temp for a given time until it has reached a state of equilibrium. An aliquot is taken from the HS using gas tight syringe and then injected into the GC.

    Models. ThermoQuest TRACE HS200, CTC COMBIPAL

    ii) Balanced-pressure system

    This is capable of generating results with a high degree of repeatability. Injection is made directly from the vial into carrier gas stream without additional moving parts other than a valve and a needle.

    Model. PerkinEmler TurboMatrix 40

    iii) Pressure-loop system

    It uses a known amount of sample. A Six-port valve is used and initially thermostats and pressurizes the vial. After pressurization, the valve is turned and the loop is filled with the sample. After the loop has been filled, the valve is turned again to redirect the gas flow and flush the sample into the transfer line leading to the column.

    Model.  HP 7694E

    Also keep into account the role of Partition Coefficient (K) i.e., the equilibrium distribution of an analyte between the sample phase and the gas phase

     K= Cs/Cg

     Cs = concentration of analyte in sample phase

    Cg  =  concentration of analyte in gas phase

    Compounds that have high K values will tend to partition less readily into the  gas phase and have relatively low responses and high limits of detection.

     e.g., ethanol in water: at 40 deg C, ethanol has a K value of 1355 in an air-water system.

     Khigh =1/ Cg low

      K can be lowered by

    Changing the temp at which the vial is equilibrated or by changing the composition of the sample matrix.     

    You may use salts (ammomium chloride; ammonium sulfate; Sodium chloride; Sodium citrate; Sodium sulfate) to decrease the matrix effects, if any.     

    Hope this will help in getting good results.

    Good Luck

    Dr Chanotiya     

  • Akhilesh Mathur added an answer in Power Systems:
    Interested in a method for determining the maximum allowable penetration level of distributed generation without steady-state voltage violations?
    Might interest some of you. I found this excellent! Credit: to the authors! Can someone mention a free source for such articles.

    Akhilesh Mathur · Indian Institute of Technology Roorkee

    Dear Divya,

    Please find the attached article...

  • Paul C. Lyons asked a question in Sandstone:
    What are the chevron-shaped structures found on the bedding planes of marine sandstones?

    Perhaps they represent energy-related  movement or some other related phenomenon.

  • Said Sabbagh asked a question in Elementary Particles:
    What is the most important water desalination, food sterilization, cancer treatment or cosmos exploration?

    What is the most important water desalination, food sterilization, cancer treatment or cosmos exploration? Why a researcher cannot find a job in the field of radiation applications while all the money goes to the elementary particles and the origin of multiuniverses?
                One of the famous theories of the string theory has said, "I do not believe that they pay me money to do such a thing", is it not so strange?

  • Hikku G S added an answer in Nanocomposites:
    What are possible reasons of decrease in intensity of SnO2 stretching mode (in FTIR spectra) by increasing content of Graphene Nanoplatelets?

    I have fabricated Graphene-SnO2  nanocomposites. In FTIR spectra of prepared samples, a peak at around 658 cm-1 referring to Sn-O-Sn stretching mode is found in case of undoped SnO2 sample which gradually decreased by increasing content of graphene nanoplatelets in case of Graphene-SnO2 nanocomposites.

    Can any body please explain some possible reasons or refer me some literature regarding this issue ?

    Hikku G S · Mepco Sclenk Engg. College

    Dear Alexander,

    Can u plz explain briefly about the "loss of 3D periodicity"? It ll be useful for our ongoing research.

  • Anca Duta added an answer in Thin Film Coatings:
    How to enhance the stability of CuO thin film photocatalyst?

    what is the suitable materials to be put on the CuO

    Anca Duta · Universitatea Transilvania Brasov

    the answer is: depends.

    You can NOT put an organic/polymeric layer because it will be photodegraded if it is thin or it will limit your photocatalytic efficinecy if it is thicker.

    You can put a very thin TiO2 layer but then you will completely change the process as you will build up a tandem system with a different activation energy (that might be for the good...)

    As I said, increasing stability also brings changes in the activation process and these changes have to be analysed/controlled.

  • Sumathi Gokulanathan asked a question in Digital Design:
    Digital parameters other than fan-in and fan-out?


    Good Day to all...

    In digital design, i want to insert control logic or lock mechanism at internal nets. As far as i know, inserting control logic or lock mechanism at High fan-out nets is the best solution in which less no. of locks will have controllability on more no. of internal nodes.

    I want to know is there any other net (means any other digital parameter to decide in which net i can insert) if i insert will impact more no. of logic, especially my concern is to increase controllability of output ports. But, fan-in will not help me for this purpose i hope...

    Thank you in advance....


  • C Michael Barton added an answer in ArcGIS:
    How can we import an excel file into Arc GIS?

    I have an XYZ spreadsheet (point data) that I would like to perform interpolation in ArcGIS. 

    C Michael Barton · Arizona State University

    Save your excel as a csv file. Import that.

  • Arpana Mishra added an answer in Seed Germination:
    Does anyone have any experience on seed germination of licorice(Glycyrrhza glabra)?

    this plant usually produce rhizomes and root to generate new plants. Also produce lot of seeds. but these seeds generate hardly. 

    Arpana Mishra · Mahatma Gandhi Chitrakoot Gramoday University


    To improve seed germination treat with 10% Lantana camara leaf extract for 7 days.

  • Mohit Saraf asked a question in Bioelectronics:
    In Glucose sensors, how much it is important to optimize the pH of supporting electrolyte? What are the other parameters which should be optimized?

    I have seen that people directly use solution of particular concentration and do the electro-chemical experiments.

     I have observed this in Very high impact journal like in Biosensors and Bioelectronics also.

    Is it right? if yes then why?

  • Kanchan Mala added an answer in Concrete Material Technology:
    Does anyone know about work-ability tests for concrete?

    has any other test (Exclude Slump Test,Vee-bee test,J- Ring,V-Funnel,Compaction factor test,U-tube & L shape test) available to measure work-ability of Concrete?

    Kanchan Mala · Jaypee University of Engineering and Technology

    Earlier I have only read the title line and not the full questions. There is one method other than mentioned above - Kelly ball method

  • Muzeeb Shaik asked a question in Metamaterials:
    What is a metamaterial and how is it useful in antenna miniaturization?

    what are the parameters that vary if we use a metamaterial 

  • Nai-Kei Wong added an answer in Reactive Oxygen Species:
    How to make a protocol on intracellular ROS detection of 4T1 mouse breast cancer cell using DCFH-DA as a ROS sensor?

    I am planning to perform gold nanocage(AuNCs)-mediated photodynamic therapy(PDT) effect to 4T1 cell under 810 nm LED array exposure, then it could induces ROS generation in cell and use DCFH-DA as a ROS detector for 533 nm fluorescent observation.

    I have three different conditions on experiment.

    First, untreated cells and no light exposure.

    Second, untreated cells and 5 mins light exposure.

    Third, gold nanocages-treated cells and 5 mins light exposure.

    Then I encountered great difficulty in observing green fluorescence, all of the three conditions expressed high green fluorescence and it was hard to identify the effect of gold nanocages-mediated PDT effort, additionally, the cells looked like more weaker the suspended cells were there, but the morphology of cells were not much changed after exposure.

    My process was after AuNCs incubation for 24 hrs, exposing 4T1 to LED array for 5 mins, then immediately exchanged medium with 5uM DCFH-DA contained PBS buffer and incubated for another 5 mins. Wash with HBSS twice, and immersed cells in fresh HBSS for 15 mins recovery time.

    Is 5uM DCFH-DA a proper concentration to 4T1 cell ,or any step caused oxidative stress in cells?

    Thank you

    Nai-Kei Wong · The University of Hong Kong

    DCF is highly photochemically unstable. 

    For alternatives, please see my comments in this previous thread:

    Please see this thread:


  • Rahimi Ali added an answer in Cross-Cultural Comparison:
    What are cross-cultural differences in terms of assessment and evaluation practices in educational settings?

    cultural differences with respect to evaluation and testing.

    Rahimi Ali · Bangkok University

    thank yoiu very much arif , I will.

  • Maimun Rizalihadi added an answer in Normal Distribution:
    Would you consider these data are normally distributed or not?

    I have two data sets the graphic representation of both is somewhat similar, however, the Shapiro-Wilk test shows one as normally distributed while the other is not. Could anyone give some hints? Thanks!

    Maimun Rizalihadi · Syiah Kuala University

    The figure clearly do not show the normal distribution, since there is not fit between data distribution and normal distribution line. You can use Coefficient skewness (Cs) to check data distribution wheter follow normal distribution or not. If Cs tend to be zero, then the data follow normal distribution. 

  • Nai-Kei Wong added an answer in Serum:
    Does anyone has an efficient protocol for a positive control using CarboxyDCFDA?

    I am trying to measure the ROS production using the CarboxyDCFDA probe, by incubating it 40 min in serum free medium, then adding a metabolisation step with serum containing medium and I am not able to have a positive control with H202 at any concentration or laoding times...

    Nai-Kei Wong · The University of Hong Kong

    DCF does not measure H2O2 in any selective manner. 

    Please see this tread:


  • Vinod Kumar added an answer in Material Synthesis:
    Any suggestion on how to reduce the agglomeration of CuSbS2 particles ?

    material synthesis based on solvothermal process. However, powder getting agglomerated even after initial drying(60 deg overnight) while grinding. Do i have to increase the annealing temp or should I have to dry it again ?

    Vinod Kumar · ICON Analytical Equipment Pvt.Ltd,Mumbai,India

    yes,you can try it,and best of luck..

  • Ru-Jeng Teng added an answer in Cell Biology:
    Have anyone ever used Merck's hydrogen peroxide solution for cell biology experiment?

    Dear All,

    I am plainning to use hydrogen peroxide to treat to cell and see it protein signaling response.

    Most of reference articles use Sigma's hydrogen peroxide  solution. Unfortunately, Sigma's hydrogen peroxide cannot be imported to Thailand. I found that Merck's hydrogen peroxide solution is available in Thailand. But I couldn't find much references about using it to cell experiment and it doesn't mention the product number. On the Merck website, the product are not specified grade clearly, (eg. ACS or cell biology) and no reference about it.

    If you have used Merck's H2O2 with cell treatment experiment, Could you kindly write me which product number is?

    Thank you


    Ru-Jeng Teng · Medical College of Wisconsin

    Have never used it. The issue is whether other components in the solution have biological effect or not. If it is not biological grade then it may contain minimal amount of heavy metals which maybe toxic to the cells or produce unexpected results. Even smallest amount of heavy metals in water can give you some free radical formation in the solution. 

  • Robert Toner added an answer in Solid Edge:
    When you import a non-true CAD file into Comsol, the dimensions of the 3D-axis re-scale from Solid Edge, is there a way for them to be maintained?


    I've been creating a .stl file in Solid Edge and importing it into comsol. But I notice the dimensions of the 3D-axis re-scale to be like a lowest common integer once in Comsol. Is there a way to maintain the dimensions from Solid Edge, or even to scale them once in Comsol, so the dimensions are the same?

    Thanks very much

    Robert Toner · University of Newcastle

    Brilliant, the scaling options in transform was what I was after. Thanks again!

  • Jitendra Singh added an answer in Ion Channels:
    Could someone help me to clear up the question about TTX and ICAN?

    Effect of TTX on calcium-activated non-specific cation current makes me confused recently. I have no idea whether the channel activity can be blocked by TTX in direct or indirect ways.

    Thank you who will give me a hand!

    Jitendra Singh · National Institute of Pharmaceutical Education and Research

    I am agree with Lijo. As the TTX will directly inhibit the sodium channel. 

  • Akhilesh Mathur added an answer in PSCAD:
    How can I model a constant power load on PSCAD/EMTDC?

    I'm designing a Dc microgrid system using PSCAD/EMTDC. so what is best representation of a constant power load for simulation purposes on PSCAD?

    Akhilesh Mathur · Indian Institute of Technology Roorkee

    First convert those constant power load into constant impedance load using the load flow solution (with power load) of the grid and then put those impedance load models at respective buses in PSCAD/EMTDC and do the analysis....this is the alternate way to treat the constant power load in the PSCAD/EMTDC..

  • Shireesh Kesharwani added an answer in Nano-Silica:
    How can prepare lipophilic form of nano silica from hydrophilic silica nano powder?

    I want to prepare lipophilic form of nano silica from silica nano powder. The nature of nano silica is super hydrophilic. So by which method we change the hydrophilic to lipophilic form of nano silica. Please send useful link?

    Shireesh Kesharwani · Saveer Biotech Limited

    Thanks Varoon and Dominik. 

    I was prepared SiO2 by C8 and C18 but both gives hydrophobic characters. 

    Varoon please send few papers.