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  • Shen-Ming Chen added an answer in Ion Exchange:
    3
    How to calculate Ion exchange capacity theoritically?

    I want to calculate the ion exchange capacity of theoretically for polybezimidazolium polymer structure.  Is there any equation has to use please specify.

    Thanking you in advance for your valuable time.

    Shen-Ming Chen

    The adsorption capacity is the maximum metal quantity uptaken by 1 g of resin.
    Maybe you can find some information from the following link:
    Separation and preconcentration of copper in environmental samples on Amberlite XAD-8 resin after complexation with a carbothioamide derivative
    http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-40422013000600016

    The Langmuir isotherm is a commonly used model to calculate the adsorption capacity of an adsorbate, as described by the following equation:
     (Ce/qe)=(Ce/qmax)+(1/bqmax)
    where qe (mg g - 1) is the amount of metal adsorbed per unit weight of the resin at equilibrium, Ce (mg L - 1) is the equilibrium metal ion concentration in an aqueous solution, qmax (mg g - 1) and b (L mg - 1) are the Langmuir constants related to the adsorption capacity and free energy or net enthalpy of adsorption, respectively. The relationship between Ce/qe versus Ce is linear, and the constants qmax and b are evaluated from the slope and intercept of the linear plot, respectively.

    Dear all Does anyone knows the equation which used to calculate The maximum adsorption capacity of resin - ResearchGate. Available from: https://www.researchgate.net/post/Dear_all_Does_anyone_knows_the_equation_which_used_to_calculate_The_maximum_adsorption_capacity_of_resin [accessed Feb 14, 2016].

  • Essam A. Al-Moraissi added an answer in P Value:
    6
    Is rejecting the null hypothesis because of p<0.05 is valid (statistically or clinically) ?

    If there was no significant difference ( p value greater than 0.05) and the null is rejecting , is this clinically valid or only statistically should be valid? 

    in others words, when the significant difference should be taken seriously ? 

    Essam A. Al-Moraissi

    Dear Jochen Wilhelm ,

    Thank your for your wonderful answer 

  • Mansour Naser Alraja added an answer in Publications:
    1
    Some publications on Roman mime?

    There are few specific publications on the Greco-Roman mime. Can they provide references to me?

    Thanks

    Mansour Naser Alraja

    Dear Marc,

    May the attached file will help.

    Best wishes,

    Mansour

  • Miriam Bodino added an answer in Public Space:
    2
    What is a "public space" in South Africa?

    I am looking at inclusive collective spaces as strategic projects acting as catalysts against the spatial segregation of the city. But I not sure that my concept of public space is conceived in the same way in South Africa.

    My case study is Cape Town, but I think that I need to undestand better the public space meaning in the South African context.

    Available for any additional information.

    Miriam Bodino

    This will for sure help!

    Thanks a lot.

  • Shen-Ming Chen added an answer in Resins:
    1
    Dear all Does anyone knows the equation which used to calculate The maximum adsorption capacity of resin

     for it determines how much adsorbent is required to quantitatively remove a specific amount of metal ions from the solutions

    Shen-Ming Chen

    The adsorption capacity is the maximum metal quantity uptaken by 1 g of resin.

    Maybe you can find some information from the following link:

    Separation and preconcentration of copper in environmental samples on Amberlite XAD-8 resin after complexation with a carbothioamide derivative

    http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-40422013000600016

    The Langmuir isotherm is a commonly used model to calculate the adsorption capacity of an adsorbate, as described by the following equation:

     (Ce/qe)=(Ce/qmax)+(1/bqmax)

    where qe (mg g - 1) is the amount of metal adsorbed per unit weight of the resin at equilibrium, Ce (mg L - 1) is the equilibrium metal ion concentration in an aqueous solution, qmax (mg g - 1) and b (L mg - 1) are the Langmuir constants related to the adsorption capacity and free energy or net enthalpy of adsorption, respectively. The relationship between Ce/qe versus Ce is linear, and the constants qmax and b are evaluated from the slope and intercept of the linear plot, respectively.

  • Gyan Chandra Chauthwani asked a question in Mathematical Concepts:
    New
    Do we really understands the ripples of space time?

    Ripples of space time what we call gravitational waves, even after the discovery of these ripples , do we really understands the physical origin of these ripples?

    I am asking it because, I even don't understand the physics of mass energy tensor to space time curvature ( a mere mathematical concept for me).

  • Victor Ostrovskii 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).

    Victor Ostrovskii

    Agostino,

    You disproved none of my arguments against the GR and big bang, you disproved no arguments by Dr. Chepick, you didn’t disprove arguments by Dr. Danci against the GR, you disproved no arguments against the GR, and you continue to repeat like a parrot: «Einstein! Einstein!”. Yes, Einstein is an outstanding scientist, but the GR is physically incorrect and inapplicable to description of the cosmological phenomena; and thus, the so-called big bang has no scientific support.

    Come off it! I don’t answer any more to your perfections in rudeness until you invent the real answers to my arguments against the GR and big bang, until you learn to discuss respectfully scientific problems with your colleagues, and until you adduce your excuses.

    As for your rude reproach that our concept of physical vacuum differs from that available in literature, we propose a new cosmological theory (PFO-CFO Theory) and there is nothing amazing that concepts of vacuum have differences in different theories.

  • Chhuon Sopheavy asked a question in Cinchona:
    New
    Can anyone explain the cultivation of cinchona ?

    Also why there are only 3 species have been cultivated.

  • Chhuon Sopheavy added an answer in Secondary Metabolites:
    4
    Could any one help describe and give the definition of different compound of secondary metabolites?

    Secondary metabolite of Medicinal plants.

    Chhuon Sopheavy

    Thanks I got the answer already :)

  • Francisco Javier Roldán-Medina added an answer in Metric System:
    3
    In the past a secret system of measures was used?

    My research detected a common measurement system in all buildings, from the protohistoric period until the introduction of the metric system. It's simple, is based on sides and diagonals of a anthropometric reference square, and is very efficient for the design and dimensional coordination works (see my publications).
    However no written sources are known. So, could it be a secret for millennia? We have a new paradigm on the measure in the past?

    Francisco Javier Roldán-Medina

    I should explain the question. The system of measures in the past was not a secret. It was the universal anthropometric system. What seems to have been secret is the sized system, because according to my research the classical unities was combined with diagonals, so that no small fractions are used.

  • Stam Nicolis added an answer in Complexity:
    16
    Are there 2-D extension of real number like complex numbers that is non-commutative?

    Quaterion is non-commutative but it is a 4-D type hypercomplex number. We also have Dual Numbers and Hyperbolic or Perplex Numbers but they are still commutative. Are there other 2-D hypercomplex numbers similar to complex number but non-Abelian?   

    Stam Nicolis

    However the examples given are all, in fact, quaternions. The square of σz/2 is proportional to the 2 x 2 identity matrix. The generalization sought for, in fact, is SL(2,C), if one imposes that the determinant be equal to unity, or GL(2,C) if not.

  • Atul Sharma added an answer in ANOVA:
    9
    Two-way ANOVA or repeated measures ANOVA?

    I have a culture of primary cells to which I measured viability at different time points. I also applied a treatment (control vs. trypsin). With time, cells divided and die. I was wondering if I should consider or not along each measure as time dependent and the test that could be more appropriate. Thanks

    Atul Sharma

    Dr. Ekstrom is quite right, in that you may want to examine the impact of other factors. A mixed effects model can be particularly useful here, by allowing you to borrow power from larger cells. 


    For cell viability counts, you could consider a Poisson model (perhaps with an offset for the total number of cells) vs time, treatment, other covariates. If the range of counts is sufficiently broad, some might approximate the count outcome as continuous and use a linear mixed effects model. But Poisson mixed models are no more complicated and more appropriate for count data. 

  • Khaled Mohamed added an answer in Calculus:
    1
    Who has conducted research into emergenent behavior?

    calculus for describing emergent behavior

    Khaled Mohamed

    These links may be useful:

    http://web.mysites.ntu.edu.sg/yhlow/public/Shared%20Documents/papers/indin06-emergent.pdf

    http://human-factors.arc.nasa.gov/groups/HCSL/publications/Gore_DHM_VDI.pdf

    http://necsi.edu/education/oneweek/winter05/NECSISoS.pdf

    You find also more information in the references of these articles. 

  • Conrad Plange asked a question in ANSYS:
    New
    How can I model a Llloyd's Mirror effect in Ansys Worbench, with the Acoustic Act?

    I want to model the Lloyd's Mirror effect for a calculation of a radiated noise from a ship, into the water. 

  • Alex Ignatov added an answer in Agriculture:
    3
    What is the highest no. of grain per spike that you find it yet? and how?

    In Holy Quran "a grain which growth seven ears, in every ear a hundred grains". It shows the potential yield that no one reaches yet. Therefore, scientists need to find missing key(s). This gives agronomists, breeders, and farmers a hope of the possibility of developing and devising distinct lines of grain and plant through good agricultural service.

    Alex Ignatov

    Average number of grains per ear in optimal conditions  can be  about 70, but some modern wheat cultivars have 80 or more. Average number of spikes per plant in field in optimal conditions  can be from 6 to 9 depending on cultivar (bread wheat).  A single grown cereal plant can produce up to 90 ears.  

  • Mauro Namías added an answer in Magnetic Resonance Imaging:
    10
    Can anyone tell why MRI denoising using non-local PCA is better than pre-filterted NLM3D (PRI-NLM3D) ?

    Based on which property PCA denoising outperforms PRI-NLM3D?

    Mauro Namías

    Dear Laraib,

    That's the problem, you need a 64bit windows to run mex64 compiled files.

  • Vadim Verlotski added an answer in Metals:
    1
    How can I measure wt % of Metal (elemental) in Metal-Metal oxide mixtures such as partially oxidized metal powders?

    How can I measure wt % of Metal (elemental) in Metal-Metal oxide mixtures such as partially oxidized metal powders?

    Vadim Verlotski

    There are various chemical and physical methods. The one easy way is, for example, gravimetry: You weigh the powder and heat it therefore to air in the oven. Rest of metal be oxidized and the powder be heavy. With this weight gain can be calculated metal content.

  • Manuel Schnabel added an answer in Organic Solar Cells:
    2
    In organic solar cells, why the dark jV often crosses the light jV?

    In the first quadrant of jV curve, it is often seen that the dark jV crosses the light jV. According to the widely accepted formula: j=j0*(exp(eV/nkT)-1)-jphoto, such crossing should not take place.

    Manuel Schnabel

    Prof. Zekry is right, but there is a second factor: aside from diode parameters changing under illumination, the photogenerated current (Iph using above nomenclature) can be voltage-dependent. In silicon solar cells it isn't, because photocurrent is collected by diffusion. In organic solar cells, photocurrent may be collected by drift, and then it is voltage-dependent.

  • Robert Kiss added an answer in Cell Line:
    4
    I'm using mouse B16F10 melanoma cells to examine the anti-cancerous effects of whole plant juice. What's a good control cell line for melanoma cells?

    I would like to obtain the LD 50 of plant juice in a noncancerous cell line so that I can compare it to the LD 50 in melanoma cells. 

    Robert Kiss

    I fully agree with Robert's reponse (and also with mine!).

    You have in the article here attached various human melanoma models and their more or less in depth biological characterization (Mathieu V et al., 2005, Van Goietsenoven G et al., 2010; Mathieu V. et al., 2012 (Oncotarget)).

    The B16F10 mouse model is indeed very agressive (see Mathieu V. et al. 2007, 2012 (JID).

    we recently analyzed the mechanisms of action of a cytotoxic natural compound that seems to target more or less selectively melanoma cells. We used melanocytes as normal cells (see Mathieu V et al., 2015).

    I do not agree with Sudip. It will be difficult to reconcile data obtained with a mouse melanoma cell lines and "pseudo"normal cells that are not from melanocytic origin.

    Best regards

    Robert

    + 5 more attachments

  • Arun Kumar added an answer in IT Systems:
    4
    What is the purpose of reducing the PAPR in the OFDM systems.?

    PAPR - peak to average power ratio

    OFDM - orthogonal frequency division multiplexing.

    Arun Kumar

    Papr stands for peak average power ratio, it usually occur when the data is added to the sub-carriers, then the amplitude goes from linear to non-linear region which greatly reduce the efficiency of non-linear amplifier. For eg. IF PAPR of system is 10 dB, than in order to transmit 1 watt of signal , 10 watt of power is required...

  • Cheng-Ying Ho asked a question in Bioinformatics:
    New
    What is the best method to analyze clonal architecture of cancer based on whole-exome or targe panel sequencing data?

    I am looking into PhyloWGS. Can someone like me without bioinformatics background use it with ease? 

  • Ajmal Okazako asked a question in CIS:
    New
    How can we distinguish between Cis and Trans isomers of a complex [M(CO)2L2] both by IR and Raman techniques?

    How can we distinguish between cis and trans isomers of the complex [M(CO)2L2] from the number of I R and Raman active stretching M- CO and M-L modes.

  • Sheng Liu added an answer in International System of Units:
    6
    What is Time?

    Time is a measure in which events can be ordered from the past through the present into the future, and also the measure of duration of events and the intervals between them. Time is often referred to as the fourth dimension, along with the three spatial dimensions.

    The fundamental unit of time in the International System of Units (SI) is the second (symbolized s or sec). One second elapses during the occurrence of exactly 9,192,631,770 (9.192631770 x 10^9) cycles of the radiation produced by the transition between two levels of the cesium 133 atom.

    "In the theory of relativity, the concept of time begins with the Big Bang the same way as parallels of latitude begin at the North Pole. You cannot go further north than the North Pole," says Kari Enqvist, Professor of Cosmology.

    According to you, what is Time?

    Sheng Liu

     Time dilation is caused by a logical contradiction, and you will understand it when you read this article.

    A new approach to the correction of

    Galilean transformation。

  • Hafidha S. Al-Barashdi asked a question in High School:
    New
    Any bibliographical reference on how to measure/evaluate SNSs addction in particular, I need to develop a questionnaire for high school students?

    I need some previous scals that i could help me build new scale for this categoury of SNSs users

  • Mary C R Wilson added an answer in Poverty Reduction:
    1
    How can zakat play role in reducing poverty?

    What are Papers on The role of Zakha in poverty reduction?

    Mary C R Wilson

    Hello

    Are these of any help?

    Ahmed, H. (2004). Role of Zakah and Awqaf in poverty alleviation. Jeddah: Islamic Development Bank, Islamic Research and Training Institute.

    http://es.nahad.ir/uploads/201.pdf

    Khan, M. F. (2007). Integrating faith-based institutions (zakah and awqaf) in poverty reductions strategies (PRS). Author is Division Chief in IRTI, IDB, Jeddah 21413, Saudi Arabia, 7-11.

    http://waqaf.org.my/wp/wp-content/uploads/2014/09/Integrating-Faith-based-Institutions-in-Poverty-Reductions-Strategies-M.-Fahim-Khan1.pdf

    Ali, I., & Hatta, Z. A. (2014). Zakat as a Poverty Reduction Mechanism Among the Muslim Community: Case Study of Bangladesh, Malaysia, and Indonesia. Asian Social Work and Policy Review, 8(1), 59-70.

    https://www.researchgate.net/publication/260410380_Zakat_as_a_Poverty_Reduction_Mechanism_Among_the_Muslim_Community_Case_Study_of_Bangladesh_Malaysia_and_Indonesia

    Hassan, M. K. (2010). An integrated poverty alleviation model combining zakat, awqaf and micro-finance. In Seventh International Conference. The Tawhidi Epistemology (pp. 261-281).

    https://www.researchgate.net/publication/228889744

    Ahmed, H. (2007). Waqf-based microfinance: realizing the social role of Islamic finance. World Bank.

    http://info.worldbank.org/etools/docs/library/240137/Paper_Microfinance%20%26%20Waqf(Dr.%20Habib).pdf

    Ahmed, H. (2008). Zakat, Macroeconomic Policies, and Poverty Alleviation: Lessons from Simulations on Bangladesh. Journal of Islamic Economics, Banking and Finance, 4(2).

    http://www.ierb-bd.org/wp-content/uploads/2010/03/journals/Journal%20Vol%2018%20No%2003%20(Special%20Issue)/Zakah,%20Macroeconoics-Habib%20Ahmed%2004.doc

    Mohieldin, M., Iqbal, Z., Rostom, A. M., & Fu, X. (2011). The role of Islamic finance in enhancing financial inclusion in Organization of Islamic Cooperation (OIC) countries. World Bank Policy Research Working Paper Series, Vol.

    https://www.researchgate.net/profile/Zamir_Iqbal/publication/228202582_The_Role_of_Islamic_Finance_in_Enhancing_Financial_Inclusion_in_Organization_of_Islamic_Cooperation_(OIC)_Countries/links/0fcfd5087df10340c7000000.pdf

    Very best wishes

    Mary

    • [Show abstract] [Hide abstract]
      ABSTRACT: Poverty reduction remains the most important challenge for policy makers in Islamic communities. The World Bank (2010: Poverty profile in Muslim world, from http://www.worldbank.org) estimates that approximately 3 billion people are living in poverty and 46 million more people will come under the income level of US$1.25 a day due to the recent global economic meltdown and slow economic growth rates. Thirty-five percent of these people are Muslims from Islamic countries. The global Muslim community has an essential role to play in addressing the injustice of global poverty through zakat. Zakat is an Islamic faith-based institution and is being underutilized for poverty reduction in many of these poor Muslim countries. Since zakat constitutes one of the pillars of Islam, it is logical to assume that policy makers among Muslims should pay serious attention to it. However, that is not the case for many Muslim countries and this paper will show that not all Muslim countries are seriously applying zakat in its strategy of combating poverty. This paper will specifically examine the role and effect of zakat in three Muslim countries (Bangladesh, Malaysia and Indonesia) providing the facts of countries that practise zakat in comparison with those that do not.
      No preview · Article · Feb 2014 · Asian Social Work and Policy Review

    + 2 more attachments

  • Alessandro Melis added an answer in Schrodinger:
    1
    Can someone send me the matlab programmes to solve nonlinear schrodinger eqation,discrete NLSE?

    P.G. Kivrikidis

    Alessandro Melis

    Dear Arvind, have a look at the attached link

  • Eduardo Marques Martins added an answer in Worldview:
    5
    Whats the best way to update a land use map from Satellite Images?

    I have a Corine 2000 land use data set and i want to update it using a Worldview Satellite Image with 8 channels.. WHat would be the best way you think?

    Eduardo Marques Martins

    Endorsing what Catherine said, probably you will need to do the same classification process for each image.

    Then, you can use the larger or more comprehensive thematic image to avoid lose much time with the concatenation.

    Success.

  • Md. Shamim Hossain added an answer in Neurodegenerative Diseases:
    2
    Differences between Multiple Sclerosis and other neurodegenerative diseases??

    It is said nowadays that MS might be a neurodegenerative disease but the question is if  it so then what are the differences between MS with other neurodegenerative diseases eg, Alzheimers disease or Perkinson disease?

    Thanks in advance,..

    Md. Shamim Hossain

    Multiple sclerosis (MS) and amyotrophic lateral sclerosis (ALS) are different diseases with some similar features and symptoms.

    They both:

    ·         Affect muscles and your ability to move your body

    ·         Attack  brain and spinal cord

    ·         Have “sclerosis” in their name

    ·         Cause scarring or hardening around nerve cells

    They have some key differences, though. MS is an autoimmune disease that causes your body to attack itself. ALS, also called Lou Gehrig’s disease, is a nervous system disorder that wears away nerve cells in your brain and spinal cord. Both are treated differently.

    People with MS often experience greater mental impairment than people with ALS. People with ALS typically develop greater physical difficulties

  • Imran .. asked a question in Crop:
    New
    In organic agricultural practices, How to make a compost which fulfill the requirements of nutrients demond?

    Organic farming practices cant fulfill the nutrients requirement. how to produce a compost to need the demond of the crop like sugarcane, sunflower or maize as these are exaustive crops.