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  • Saravanamuttu Subramaniam Sivakumar added an answer in Water Management:
    5
    What portion of Water stored in surface irrigation schemes can be used for domestic and other use possible?

    By adopting good water management practices (by reducing the duty of water for cultivation) definitely you can achieve this. But the question is how to convince the agriculture users.

    Saravanamuttu Subramaniam Sivakumar

    https://www.researchgate.net/publication/274712710_Workshop_on_Water_Conflicts_Resolution_Treatment_Desalination_by_WaSo_Project_of_Department_of_Civil_Engineering_University_of_Jaffna_18-19th_April_2015

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: Iranamadu Tank is located in the KanagarayanAru river basin of the Northern Province of Sri Lankawith a catchment area of 581 square kilometres (sq km). KanagarayanAru River is 58 km long and flows towards northern part of the country across Vavuniya and Mullaitivu Districts ending at Kilinochchi District border. Iranamadu irrigation settlement scheme in the Kilinochchi District, was established in several stages since 1902. The construction of the original Iranamadu tank with a capacity of 49 MCM commenced in 1902 and was completed by the Irrigation Department. In 1951, the tank bund was raised to hold a capacity of 88 MCM. The tank was raised for the third time in 1954 to hold a capacity of 101 MCM and again for the fourth time in 1975 to the present capacity of 131 MCM. Under the scheme each family was given a holding ranging from 1.2 to 4 ha of paddy and 0.6 ha of homestead. The LB sluice irrigates 7,265 ha and RB sluice irrigate 1,190 ha. In addition there is a Lift Irrigation Scheme irrigating 447 ha in ThiruvaiAru area. Total number of families in Kilinochchi district is 21,208 and of them 9,100 or 40% are in the Iranamadu scheme. Paddy is cultivated under this scheme. Farmers cultivate their full extent of paddy land during Maha season. Yala cultivation is limited depending on the availability of water in the tank. Irrigation Channel Systems spreading over the command area of 8,455 ha are badly eroded and scoured along almost the full lengths due to poor maintenance over a long period of time because of the war. Beds of the channels are heavily silted and weeds have grown on the silted bed at many locations. Most of the concrete control structures along the channels are also badly damaged. Conveyance loss of irrigation water is very high due to the damage of irrigation structures. Many of these need reconstruction and extensive repairs and improvements. Due to the prevalence of such an uncontrolled system at present, the percentage of water loss is very high, depriving the cultivation of a significant extent of paddy land during Yala.Use of water goes up to about 7 acre feet or even more during Yala. By rehabilitation and ensuring efficient water conveyance and management system there is a possibility of increasing the present cropping intensity of 1.18 to 1.35 and even further with crop diversification.
      Full-text · Conference Paper · Apr 2015
  • Azzam K Almosallami added an answer in General Relativity:
    99+
    Universe is static!!! Yes or no?

    Space of Universe is static! Yes or no?

    Question: Are there any observations that do not fit into the model static space of Universe, are there any theoretical obstacles to the existence of such a model?

    I assume that the Universe is eternal, infinite and static, it is not expanded and not curved, it is possible to construct a preferred inertial frame of reference in which the CMBR is most isotropic. The matter in this space evolves, but the average density of matter and energy (in large enough volumes) fluctuate within a rather broad range.
    The light in this model is "tired", the speed of light depends on the optical density intergalactic medium. Gravity is also "tired" t.i. weakens a little faster R2. The energy of destroying matter goes into the surrounding vacuum. The excess energy from the vacuum give rise to new particles of matter.

    I state that all the observed cosmological effects can be explained in such a Static Model of the Universe.
    See attached "Basic_Cosmological_Formula_1_En.pdf"

    Dear colleagues, I do not ask, what are the problems faced by other theories (though I would be interested in your opinion on that. The General theory of relativity is not applicable to the entire space of the Universe).

    Azzam K Almosallami

    Dear Erkki J. Brändas, 

    You have not replied to me by physics in order to reply to you by physics.

    So, do not look at the world by one eye. God created for us two eyes... not one eye! Geometry does not govern the universe. Geometry in relativity is only a game to appear how the world is moving according to objectivity and continuity. Physics is not mathematics. I understand well how math is very important for physics and there is no physics without math, but also physics is not mathematics. Physics proves math, but math does not prove physics. 

    Relativity and its math is only "Look at the world by one eye...Look at the world as a picture upside down" Look at the London-Paris problem and you will understand all of that. Also review the equivalence principle of Einstein well, you will understand that.

    Relativity put all the world in Plato's cave!!!

    Read this paper "Lorentz invariance on trial Maxim Pospelov and Michael Romalis"

     http://physics.princeton.edu/romalis/articles/Pospelov%20and%20Romalis%20-%20Lorentz%20Invariance%20on%20Trial.pdf

    + 1 more attachment

  • Saravanamuttu Subramaniam Sivakumar added an answer in Methane Production:
    1
    Do you recommend any research papers that show the balanced synthetic nutrient composition required for the anaerobic digestion?

    A nutrient composition containing protein, lipids, carbohydrates, etc. to enhance methane production. 

    Saravanamuttu Subramaniam Sivakumar

    The link below will give you some useful hints

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: Water scarcity of drinking and agriculture is one of the immerging issues today. Few interrelated salinity reduction methods were experimented, namely; charcoal filter bed, charcoal and compost leaching columns with clay and waste polythene liner and uptake by Typha angustifolio plant biofilter. Parameters such as EC, salt%, pH, TDS, DO and organic content of brackish water were 6.31 mS/cm, 3.2%, 3370 mg/l, 6.4, 7.9 mg/l and 0.147%, respectively. It is certain that charcoal on its own will not act as a biofilter to desalination. As alternative, mature compost can be used, since it contains substrate for the microbial population, removes around 3/4 of the salinity with liner system. Typha did survive at moderate salt concentrations and it did remove 1/3 of the salt. In fact, the field scale biofilter system removed around 2/3 of the salt. This study narrows down to combine; mature compost, Typha and the liner system to remove 100 % of the salinity. However, the hydraulic conductivity of the liner system should be increased by modifying the liner. This can be use for irrigation of salt loving crops, industrial use or even for domestic use. Key words: Clay waste polythene clay liner, leaching columns, filter bed, salinity and Brackish water
      Full-text · Article · Jul 2013
  • Sebastián Dupraz added an answer in Amacrine Cells:
    3
    Role of Frmd7 in Rho/GDPase signalling in the retina?

    Hi, I'm trying to investigate the effect of Frmd7 gene (a gene involved in idiopathic nystagmus, an eye condition) in Rho/GDPase signalling, it has been reported that it plays role in activating Rac1 and reorganisation of actin cytoskeleton. I want to look at Rho/GDPase signalling in presence and absence of Frmd7 in the retina, specifically in amacrine cells (where it's expressed). Can I do that with specific markers for Rho/GDPase signalling, and look at changes in activity in wild type and mutant retina lacking Frmd7 (I have a knockout model for Frmd7)?

    Sebastián Dupraz

    Hi Ahmed, I totally agree with Sebastian's comments above. If you find alterations in the actin cytoskeleton these alterations itself may give you a hint about the type of Rho family member involved. Give special attention to possible modifications in the balance between lamellipodial and filopodial protrusion as well as the formation of stress fibres.

    Have a good fishing!

  • Jack M Gallup added an answer in EDTA:
    1
    How do you dilute LAMP primers? In water or in TE buffer?

    I'd like to know which one is better for the primer stability. If you use TE buffer do you buy or prepare it in the lab? Which concentration of EDTA do you use?

    Jack M Gallup

    Hi Livia,

    According to IDT and other companies, TE pH 8.0 is the safe way to initially dilute primer lyophilates to make your primer stock solution (typically 100 uM).  Primers, being short DNA sequences, are more stable at pHs above 7.  A good recipe for TE is:

    http://nature.berkeley.edu/soilmicro/methods/TE%20buffer.pdf

    Be sure the water is nuclease-free when preparing.

    Ambion sells TE as well as nuclease free water - as do other companies..

  • Sinan Baho asked a question in Growth:
    New
    Why we get a new log phase?

    during the growth curve experiment, why sometimes we get a new log phase during the stationary phase of the growth?

  • Charles Francis added an answer in Cosmology:
    61
    Is there Godel's Incompleteness Theorem in Physics like in Mathematics?

    The holy grail of Physics is the Unification Theory called by Weinberg as the "Final Theory". When finally discovered, perhaps it can:

    1. Unify all fundamental forces in nature.

    2. Explain the Hierarchy Problem

    3. Explain all Cosmological Problems 

    5. Gives us the right Quantum Interpretation

    but can such theory derive all fundamental dimensionless constants in nature out of pure number and explain the true nature of time?  

    Charles Francis

    Leyvraz, you are talking of a different issue. This does not have to do with Godel's theorem but to do with statements which must logically either be true or false, but for which we are unable to determine which is correct. Godel's first theorem specifically concerns the statement "this sentence is not provable", which cannot be either true or false. 

    A part of the problem is that we cannot go through all the integers, but I doubt whether we could expect to know whether we could determine the truth of every possible statement, either in mathematics or physics. On the other hand, we may be able to determine the fundamental rules governing physics, since that is likely to be a finite problem.

  • Luisiana Cundin added an answer in Linear Systems:
    3
    What are the methods of solving multiple linear systems?

    Can you please provide some information about methods (iterative or any) which are available to solve multiple linear systems? 

    Are they same for multiple  non- linear systems?

    Luisiana Cundin

    There are many methods...see link

  • Mark Vi added an answer in Numerical Analysis:
    2
    Approximated forced response for Nonuniform E-B cantilever with elastic clamp ?

    Hi, am trying to use approximated methods (Galerkin method). My understanding is, that I have to choose a comparison function that satisfies the Geometric boundary conditions. However, the beam configuration has only natural BC (one end has a torsional spring, the other is free).

    Mark Vi

    Khaikh Thank you for providing these literature, fortunately I went through them before asking this question.

    However, my question is not answered in these researches. I found that the problem is more complicated in such a way that if the beam lack any geometric BC we have to use a combination of admissible functions.

    Please anyone has some thoughts, please share

    Thanks

  • L. Van Zwieten added an answer in Soil Science:
    3
    Does anyone has an Idea How to sterilize a soil ?

    for inoculation of biofertilizers.

    and for my research methodology.

    Thank you very much

    L. Van Zwieten

    Greetings. We have had success using gamma irrigation. This is usually provided as a service which is relatively inexpensive.  many suggest that it is less disruptive to the soil chemical and physical properties. In our paper (quin etal 2015) there was an increase in extractable nitrate, but this appeared to be the only major change. Hope this helps

  • Saravanamuttu Subramaniam Sivakumar added an answer in Water Management:
    1
    What are the most common Water Management Practice in India highland and Lowland Enivorment?

    I am looking in to existing Water Management Practice in India and how they can be replicated in South Sudan to address the existing water management challenges.

    The work will base on case studies, both primary and secondary data collections.

    After going through various practices commonly used in highland and lowland, then the best practices will be recommended after rating is done with water experts in Africa through some interviews.

    I am seeking some materials support on this case studies and other vitals research works on Water Management Practice in India in lowland and highland..

    Any kinds of supports will be greatly appreciated.

    Saravanamuttu Subramaniam Sivakumar

    https://www.researchgate.net/publication/265511366_Effective_Utilization_of_Available_Water_Resource_by_Following_Proper_Irrigation_Practices_in_Sri_Lanka

    My article above is dealing with water management practices in Sri Lanka. May be useful to you

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: Sri Lanka is a pearl shaped island situated about 35 km. from the southern tip of India. It is exactly 880 km. north of equator and this land of 65,610 sq. km is only 435 km. long and 225 km. across it's widest. Monsoon rains occurring during the two distinct periods from May to Septem-ber namely the South-West Monsoon and from December to February the North-East Monsoon along with the convectional and depression rainfall dur-ing the inter monsoonal periods contribute to the annual precipitation. Sri Lanka is divided into 103 natural river basins, with catchment areas ranging from 10 to 10,500 sq. km. Sixteen of these rivers flow through the wet zone. The base flow of these perennial rivers of wet zone are very low and flood discharges are high. The streams in the dry zone have poor run-off and are generally not perennial. The annual precipitation is about 110,000 million cu. meters, the run-off being 47% of this. The wet zone contributes 40,000 million cu. meters of perception of which the run-off is 65%. The practice of irriga-tion in Sri Lanka has a tradition of over two thousand years, with the first earth dam believed to have been constructed in 504 BC. The earliest settlers from India in Sri Lanka possessed a knowledge of irrigation and rice cultivation, having presumably settled on the flat dry zone plains which were ideal for rice cultivation. This research article deals, how the water resource is effectively utilized by following systematic scientific and proper irrigation prac-tices in Sri Lanka.
      Full-text · Article · Sep 2014 · International Journal of Scientific and Engineering Research
  • Raam Kasinathan asked a question in Amorphous Carbon:
    New
    SEI formation in Amorphous and Coated Graphite?

    D I have noticed that the amorphous carbon also exceed the stability potential window. Does it form any SEI layer and how it can be compared with Graphite SEI (in sense more SEI than Graphite or lesser)?

    What about coated Graphite (Amorphous carbon coated graphite)? Does the coating increases the rate capability?

  • Saravanamuttu Subramaniam Sivakumar added an answer in Systematics:
    1
    People working any aspect of Tardigrada or Bdelloidea in México?

    Tardigrada and Bdelloidea research in México is very limited, so I would like to identify researchers or grups on these topics to make a network. I work mainly on systematics of Tardigrada and Bdelloidea groups. 

    Thanks for your answers

    Saravanamuttu Subramaniam Sivakumar

    https://www.researchgate.net/publication/293062530_IPWE2016OnsiteProgram-FINAL

    The above link will give you some useful articles

  • Martín Cañón added an answer in ANOVA:
    2
    Is there any assumption to be verified in a crossover model?

    Dear all,
    I need your help to clarify the following doubt about the crossover design and the underlying model, please.
    Is there any assumption to be verified for the validity of this model?
    For instance, I know that for an ANOVA model for repeated measurements, there are some tests about sphericity/compound symmetry.

    Is there anything like even for the crossover?

    Many thanks for any clarification!

  • Saravanamuttu Subramaniam Sivakumar added an answer in Surface Water:
    8
    How to assess the impact of climate change on surface water supply system ?

    I want to assess the impact of Climate Change ( precipitation, temperature, salinity intrusion) on water supply ( surface water ). For this I do not get proper literature. Kindly suggest me some references and your views to do the work.

    Thanks & Regeards

    Juthika

    Saravanamuttu Subramaniam Sivakumar

    You can get few research articles from this link

  • G. Wilson Fernandes added an answer in Biodiversity:
    4
    Are mobile phone apps useful for biodiversity inventory, monitoring, citizen science projects?

    I've been trying iNaturalist and a few other mobile phone apps (Map of Life, eBird, PlantNet, Urubu, SISS-Geo) for over a year and found that many users start but do not continue using them. Moreover, due to the existence of several apps, none of them has a complete list of species and none has all desired functions and features.Citizen perspective:In your experience, do you believe common citizens find the apps user friendly and are able to use them effectively to learn and add data to science?Science perspective:Are scientists, mainly taxonomists, engaging in this initiative to help people learn about nature? If not, why? Is the data generated by citizens, useful for science (biogeography, conservation)?

    G. Wilson Fernandes

    I totally agree with what has been said.  Otherwise, there are ways of improving it.  For instance, we could work on higher taxonomical levels when dealing with more complex systems!  Mobil phones might be useful indeed.  But again, a good data base is needed but we should develop some type or smart applications that recognize the beast and name it! We could start with some colorful and distinct butterflies, dung beetles and galls (if we know the host...).

    Regards,

    Wilson

  • Mirjana Vukovic added an answer in Homogenization:
    3
    Pb particles 5µm – 500 nm from bulk lead and solvent for them?

    What is the easiest way to produce small particles of Pb from bulk lead with sizes of 5µm – 500 nm (narrow size distribution is not needed) and what solvent can I use for them, that evaporates relatively fast at room temperature?I would like to introduce them homogeneously into a polymer, which I also get from solution and let the solvents evaporate. I would be thankful for a very easy recipe since I am not a chemist, but a physicist :)  

    Mirjana Vukovic

    I am so sorry, but I'm not expert for this problematic.

  • Catherine Baumgartner added an answer in Gut Microbiome:
    9
    What are the most important findings to date about links between circadian rhythms and the microbiome?

    There seems to be an increasing amount of research documenting important links between circadian rhythms, the gut microbiome, and health outcomes related to the immune system, HPA stress response, metabolism, and overall well-being. 

    What are the most important findings to date...? And to what extent is the gut-brain axis involved in these interactions?

    Catherine Baumgartner

    From April 2015:

    Anderson, G., & Maes, M. (2015). The gut–brain axis: The role of melatonin in linking psychiatric, inflammatory and neurodegenerative conditions. Advances in Integrative Medicine, 2(1), 31-37.

    https://www.researchgate.net/publication/278244448_The_gut-brain_axis_The_role_of_melatonin_in_linking_psychiatric_inflammatory_and_neurodegenerative_conditions

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: Recent work has highlighted the importance of immune inflammatory processes, oxidative and nitrosative stress (O&NS) and tryptophan catabolites (TRYCATs) in the aetiology of depression and many depression-associated disorders, including other psychiatric, neurodegenerative and wider medical disorders. A recently researched aspect of the aetiology and course of depression has focussed on the role of gut permeability and gut microbiota. Increased gut permeability is evident in many medical conditions, contributing to increased immune inflammatory cytokines, O&NS and neuroregulatory TRYCATs. By driving tryptophan down the kynurenine pathways and away from serotonin, Nacetylserotonin and melatonin synthesis, such processes alter the nature of central processes, but also contribute to changes in gut permeability regulation. Here we look at the role of decreased melatonin in gut permeability, especially via its regulation of the inflammasome. This has important consequences across a host of medical conditions, including Alzheimer’s disease, non-alcoholic fatty liver disease, obesity, fibromyalgia and alcoholism, as well as in the aetiology and course of depression. Such work emphasises the importance of central and systemic interactions, and has implications for the etiological conceptualisation, classification, course and treatment of a diverse array of medical conditions.
      Full-text · Article · Apr 2015
  • Rafik Karaman added an answer in Adsorption:
    1
    A generic method for column adsorption experiments ?

    Greetings to all, anyone can help me with a generic procedure for column adsorption experiments, thank you.

    Rafik Karaman

    Dear Jorge,

    Attached is one of our recent publications on the use of adsorbents in removing pollutants (batch and column experiments):

    I have copied the experimental part for quick view:

    2.2.5. Adsorption studies on micelle–clay complex and charcoal
    2.2.5.1. Batch adsorption isotherms Equilibrium relationships between adsorbents (micelle–clay complex and activated charcoal) and adsorbate (amoxicillin trihydrate
    and cefuroxime axetil) are described by adsorption isotherms which were obtained at adsorbate concentrations of 100, 200, 300, 400 and 500 ppm, prepared in distilled water at pH 8.2 (adjusted by 1M NaOH). The following procedure was applied: 100 mL from each solution was transferred to a 200 mL Erlenmeyer
    flask; 0.500 g of the micelle–clay complex or activated charcoal was added to the flask. Then the flask was placed on the shaker for 180 min. Afterwards, each sample was centrifuged for 5 min, and filtered using a 0.45 μm filter. A study on the kinetics of adsorption was conducted by introducing 100 mL of 100 ppm amoxicillin trihydrate and cefuroxime axetil solutions into 250 mL flasks containing 0.500 g of either micelle–clay or charcoal and determining the concentration of amoxicillin trihydrate and cefuroxime axetil. The concentration of amoxicillin trihydrate and
    cefuroxime axetil as a function of time was determined spectophotmetrically by recording the absorbance at λmax of 273 and 278 nm, respectively.
    2.2.6. Analysis of adsorption isotherms
    Equilibrium relationships between adsorbents (micelle–clay complex and charcoal) and adsorbate (i.e. amoxicillin trihydrate or cefuroxime axetil) were described by
    the Langmuir adsorption isotherm which is considered the most widely used modelling for equilibrium data and determination of adsorption capacity.[27]
    The linear form represented by Equation (1) was employed:
    Ce/Qe = 1/(K Qmax) + Ce/Qmax, (1)
    in which Ce is the equilibrium concentration of amoxicillin trihydrate or cefuroxime axetil (mgL−1), Qe the equilibrium mass of the adsorbed amoxicillin trihydrate or
    cefuroxime axetil per gram of complex or activated carbon (mg g−1), K the Langmuir binding constant (L mg−1) and Qmax the maximum mass of amoxicillin trihydrate or cefuroxime axetil removed per gram of complex (mg g−1).
    2.2.7. Column experiments
    In the first experiment, a 25/1 (w/w) mixture of quartz sand and ODTMA-clay complex or granular activated carbon (GAC) (20 cm layer) was included in a column (25 × 5 cm). The bottom of the column was covered with a 3 cm layer of quartz sand. The quartz sand was thoroughly washed by distilled water and dried at 105°C for 24 h prior to its use. A wool layer of 2 cm was placed at the bottom
    of the column. One thousand millilitres of 100 ppm amoxicillin trihydrate solution were passed through the column at a fixed flow rate of 2 mL min−1. For cefuroxime
    axetil, 1000 mL of 50 ppm cefuroxime axetil solution were passed through the column at a fixed flow rate of 2 mL min−1. Eluted fractions of 100 mL (each) were collected, and the concentrations of amoxicillin trihydrate and cefuroxime axetil were determined spectrophotmetrically at λmax of 273 278 nm, respectively. All experiments described were conducted in triplicates. Additional filtration experiments employed the same columns, but with a 50/1 (w/w) mixture of quartz sand and ODTMA-clay complex or GAC (13 g) and the volume passed was several litres, at flow rates of 50 or 60 mL min–1.
    2.2.8. Adsorption and convection in a column filter
    The adsorption and convection are described by Equation (2) whose numerical solutions were executed by a FORTRAN program.[28] Briefly, a column of length L is filled with material, whose initial molar concentration of adsorbing sites is R0, whose concentration changes later to R(X,t). The beginning and end of the filter are at the coordinates X = 0 and X = L, respectively.We consider that the pollutant concentration at the inlet, C0 is constant, that is, C(X, t) = C0, X ≤ 0, where t denotes time:
    dC(X , t)/dt = −v∂C/∂X − C1 ∗ C(X , t) ∗ R(X , t)
    + D1(R0 − R(X , t)) . . ., (2)
    where C1 (M−1 min−1) represents rate constant of forward adsorption, D1 (min−1) the rate constant of desorption and v (cm min–1) the flow velocity.
    The statistical criteria for the goodness of the fits were the closeness of R2 to unity, and RMSE, the root mean square error, which is given by RMSE = (yi,exp − yi,calc)2/(n − m) 0.5 , (3)
    in which yi,exp and yi,calc are experimental and calculated values of per cent removal from water of the pollutant by the filter, n the number of data points and m the number of parameters. In our case, the parameters were R0, Ci and Di.

    To view the full paper, please see attached file.

    Hoping this will be helpful,

    Rafik

  • Student fk added an answer in Matrigel:
    3
    MCF10A acini recovery from matrigel for RNA isolation?

    Hello

    I am trying to recover my acini for RNA isolation from matrigel. However, even after incubation in the Corning® Cell Recovery Solution (Product #354253), I find that there is "goop" or gel when I try to pellet my cells. The incubation was on ice for 1h. The centrifugation was at 200g for 5 min at 4 deg. I am unable, as a result, to recover the acini efficiently for lysis and RNA isolation. Any advice would be appreciated.

    Student fk

    Incubation with dispase may improve cell recovery

  • Roland Hildel added an answer in Polymerization:
    1
    What is the intrinsic properties of rubbery polymer?

    What is the intrinsic properties of rubbery polymer?

    Roland Hildel

    Elastic behavoir gives the difference to the more ore less stiffer polymers.

    Same crosslinking is a Need-to much crosslinking gives resinous products.

  • P. Grima Gallardo added an answer in Doping:
    3
    In XRD peak, when ever doping materials the peaks will be shifted left to right (or) right to left why?

    Ex, Sr doped La2CuO4 in XRD peaks will be shifted right to left.

    P. Grima Gallardo

    I agree with Dr. Bhange.

  • P. Grima Gallardo added an answer in ZnO:
    3
    Is the extrapolation graph of [(αhv)2 vs E] almost similar to extrapolation graph of [(αhv)1/2 vs E]?

    Hi all, 

    I plotted two types of graphs, (αhv)2 vs E and (αhv)1/2 vs E in order to determine the energy band gap of ZnO nanowires for my sample. 


    As we know, ZnO is direct band gap which means that extrapolation graph of (αhv)2 vs E will fit the correct transition type.

    But somehow, it bothers me because I obtained the similar pattern graph of (αhv)1/2 vs E.


    Can anyone help me to explain why I need to choose the extrapolation of graph (αhv)2 vs E, instead of (αhv)1/2 vs E from the graph I attached below.


    Thank you.

    P. Grima Gallardo

    Semiconductors have both energy gaps, direct and indirect. Generally, the indirect gap is lower than the direct gap, as you obtain in your experiment. Althought is well known that ZnO is a direct gap semiconductor, in your case, you have nanowires and not a bulk sample. It could be possible than in the case of nanowires you can observe also the indirect gap. Do not discard anything, may be you have important information. 

  • Timothy O Randhir added an answer in IDRISI:
    1
    I have land suitability map by using AHP,generated in Arcmap. I want to use it with CA-Markov model in IDRISI SELVA. How can I insert it?

    I generated land suitability using GIS-AHP IN Arcmap10.2. I want to predict land use change using AHP land suitability map with CA-Markov in Idrisi Selva.

    Timothy O Randhir

    You can import the data by opening Selva and importing the ArcMap data using the esri import facility available in Selva. It will be helpful to use the same raster formulation in Selva. CA-Markov needs two or more land covers over time.

  • Md Riaz Kayser added an answer in Molecular Modeling:
    5
    How do I make a potential file for LAMMPS simulation if I already know all the parameters of Exponent-6 potential?
    For instance, are there some professional softwares to do this?
    Md Riaz Kayser

    Hello, I want to simulate HfB2 in lammps. I have the potential from this paper(http://www.sciencedirect.com/science/article/pii/S092702561100262X). But I dont know how to incorporate this potentials with lammps. Can anybody please help. Thanks.

  • Pierre Nobosse added an answer in Bioengineering:
    3
    How to determine the average molecular weight of waste frying oil ?

    i have been working for the optimize condition for the max. production of bio diesel from waste frying oil of chicken and fish. 

    Pierre Nobosse

    Dear Researchers

    Determination of MW of oils is based on the assumption that the given oil content is made of stable TG or fatty acid. Fish and chicken oils are mainly unsaturated fatty acids. So, Waste frying oil from these sources is a mixture of free short chain acids, hydroperoxides, volatile compounds, some saturated fatty acids... So the assumption is not longer respected.

    Regards!

    NOBOSSE.

  • Badreddine Saidi added an answer in CATIA:
    3
    How can I use displacement from CATIA advanced machining in Abaqus ?

    i wich to create à displacement punch (complex form) with catia adavanced machining and insert it in abaqus lika a amplitude.

    Badreddine Saidi

    thanks, for your answers we use the amplitude method, bat my punch dsiplace and rotate in same time, i hope discover a method to import the punch parcourt from Catia to abaqus.

  • Timothy O Randhir added an answer in OLS:
    1
    Suppose predictors in an OLS have all been dichotomised. In such a case, can one compare the standardised coefficients?

    My readings over a few weeks now have revealed that it is incorrect to try to compare unstandardized correlation coefficients (the same way one cannot compare fruits to colors) when the units of measurements are different. King (1986) makes a strong case and has proven theoretically that standardisation of variables adds no meaning to the explanations. He even shows that it is inappropriate to compare standardised coefficients as long as the units of measurements differed from the start.

    In the case when one has dichotomised all variables, is it possible to compare their unstandardized betas (and the standardised for that matter)?

    Timothy O Randhir

    Dichotomized variables have a different distribution and use of OLS will be defective. Sometimes dummy variables that represent categorical variables is used but interpretation of these should be carefully considered. If the dichotomous variable is transformed based on some criteria it need to be interpreted carefully based on that transformation. A problem with use of OLS is that the beta can affect slope or intercept depending upon the specification of the model.

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