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- NewHow can I wash silica particles that are made stober process?
I have some problems about washing silica particle that are made stober process.
For washing, i just add ethanol and water. Then, I centrifuge mixture ( 13000rpm, 15min)
However, I found that precipitate is like a gel. In SEM images look like the smooth board.
Is it normally phenomenon? Or Am i missing step?Following
- 2What is the difference between Hanle effect and Faraday effect other than the direction of magnetic field?
I know that in Faraday effect B isparallel to the direction of propagation(k) of linearly polarized light which induces a difference in the refractive indices of the RCP and LCP components of the LP light (in a dielectric medium), which causes a rotation of the plane of polarisation.
In Hanle effect B , k and polarisation direction are all mutually orthogaonal.
Thank you for the explanation. Faraday effect is pretty clear to me now, but could you please elaborate on Hanle effect a little more.Following
- 87Why is there something instead of nothing ?
LET US START BY WHAT Robert Adler WROTE ON 6 NOVEMBER 2014--:
People have wrestled with the mystery of why the universe exists for thousands of years. Pretty much every ancient culture came up with its own creation story - most of them leaving the matter in the hands of the gods - and philosophers have written reams on the subject. But science has had little to say about this ultimate question.
Dreams are real as long as they last. But I have never made precise experimental measurements like these in my dreams.
These measurements, made in the Physics Department at UC Berkeley in the summer on 1964, showed that neon isotopes in the dark-portion of the Fayetteville meteorite were a mixture of
- Cosmogenic Neon made by nuclear spallation reactions when the meteorite had been bombarded with high energy cosmic rays
- Severely Mass-Fractionated Neon isotopes implanted from by the solar wind from the top of the solar photosphere to finely crushed, dark portions of the Fayetteville meteorite
- NewHow can we approach patients with transplant glomerulopathy in the absence of C4d deposition and donor-specific antibodies?
patients with tx glomerulopathy have been seen commonly recently. management of tx glomerulopathy is diffucult.Following
- NewHas anyone applied SPSS tests to their antioxidant & antibacterial activity of compounds or extracts?
Has anyone applied SPSS tests to their antioxidant & antibacterial activity of compounds or extracts?Following
- NewAny scholar who has researched on Portfolio Theory in Animal Breeding?
I need more insight in this area. Any article I can be referred to for further reading will be highly appreciated
This paper: Interdisciplinarity, Internationalization, Interculturality: Three Challenges of Training in Animal Breeding and Genetics in Europe by E. Verrier, T. Heams of
AgroParisTech, Paris, France will be of help. It is paper publication on the Proceedings of 10th World Congress of Genetics Applied to Livestock Production I hope it helpsFollowing
- 2What is the meaning of a negative peaks absorption in NH3-TPD?
what is the meaning of a negative peaks absorption in NH3-TPD? samples are mixtures Nb2O5-alumina and Nb2O5-silica. How i can determine amounts of NH3 desorbed in mmol/g in those curves?Following
- NewIs there anyone in particular, blast modeling in ls-dyna help me?
Is there anyone in particular, explosion modeling in ls-dyna help me?Following
- 8Which Likert scale should I prefer that of 1-4, 1-5 or 1-7?
I'm making a questionnaire for my students about my new teaching style. My question is about the best Lickert scale that I can use in order to they evaluate some statements: 1-4, 1-5 o 1-7? I have read about this, but there are advantages and disadvantages in each of them. Can anyone help me out?
Thank you in advance.
I too agree that 4 point scale has obvious limitation. So, the obvious choice would be either a 5-point scale or a 7-point scale. In my own research projects, I have used both 5-point as well as 7-point scales in SEM models and both have produced decent results. So analysis wise i do not think it would make much of a difference and in literature we find evidence that supports use of both kinds of scales.
Personally, i prefer 7-point scale as it surely gives more options to respondents for discriminating between 7 choices.Following
- NewHow I can make aqueous solution of Bi(NO3)3.5H2O for electrodeposition with pH 3-4?
Actually I have tried many times but when I dissolve Bi(NO3) 3 in distilled water it forms precipitates of sub-nitrates. I also tried to make solution by adding 3ml of HCl, in this time Bi(NO3) 3 is dissolved and clear solution is formed but pH goes to 1.Following
- NewWhat is the best chemical method for synthesis of graphene oxide from graphite?
I am reasonably new to this area of reasearch. I have searched literature and found different chemical methods for synthesis of graphene oxide from graphite. The most common method was Hummers modified and improved method. I decided to use modified hummers method but different literature mentioned different experimental conditions (particulary the temperature used in the synthesis) though the chemicals employed remained same for most procedures.
Can somone provide an optimal procedure with reliable literature for the synthesis of graphene oxide from graphite using modified Hummers method?Following
- 2What is the reason of shifting FTIR curve picks to higher or lower wavenumbers?
i have recognized the bonds which refers to any pick.but can anybody help me please to find the reasons for picks transfer by changing the materials used for our mixture? here is a sample of FTIR analyse
I do not know the composition of the mixture but generally speaking, the spectral position of the molecular groups can be affected by the different environmentFollowing
- 5When is it important to consider socio-economic status in systematic reviews?
Under what circumstances would it be important that systematic reviewers consider the impact of their findings on health inequalities across SES populations in systematic reviews?
Fundamentally, I would answer your question by saying SES is very important and should be considered. As a reviewer, however, if would be a function of your fundamental review question. If you plan to look at SES then I would suggest setting up your review question to account for this. If performing a meta-analysis, you could subgroup your findings by SES which would then allow you to perhaps look at ALL literature on a particular review question with our regard to SES and THEN you can stratify your recommendations based on SES.Following
- 4Why can’t I label pCREB in rat brain with my immunohistochemistry protocol?
I’m trying to label pCREB with anti-CREB (phospho S133) antibody [E113] (ab32096), Donkey Anti-Rabbit IgG H&L (HRP) ab6802 and with DAB, all from Abcam. I haven’t been able to get a real staining with the protocol I’m using.
I’ve used this same protocol for staining BDNF (with most of the same reagents except the antibodies) and didn’t get any troubles. Also, I got good results with pCREB when I used immunofluorescence by changing the secondary antibody, DAB and the Mayer’s Hematoxylin for Anti-Rabbit IgG (whole molecule), F(ab¢)2 fragment–Cy3 (C2306; SIGMA) and ProLong® Gold Antifade Reagent with DAPI
Does anyone have any advice on what the problem could be?
For more details:
In the protocol I realized antibody retrieval with citrate buffer pH 6.0 during 20 min at 95 °C. I carry out a permeabilization step for 30 min with PBS 0.1 M Tween 20 at 0.03%. In the first stages of the staining, the samples were washed with PBS 0.1 M Tween 20 at 0.03% and, afterwards, they were washed with PBS 0.1 M only. The primary antibody anti-CREB (phospho S133) antibody [E113] (ab32096) 0.03 µg/µl was incubated overnight at 4 °C, then the endogenous peroxidase was blocked with blocking reagent (ab64218), the secondary antibody Donkey Anti-Rabbit IgG H&L (HRP) (ab6802) 0.004 µg/µl was incubated for 2 hours at room temperature and a chromogenic reaction with DAB (ab94665) was carried out. I stained the nucleus with Mayer’s Hematoxylin (ab128990) and mounted with ab64230 mounting medium.
I would appreciate any advice you could give me.
No, because of the contrast of blue and brown. But if you want to detect faint brown positivity, you may diluate Mayer’s Hematoxylin, or decrase the incubation time or more intense washing after Mayer's. Another option is so called green counter stains, but I don't think there will be a significant difference.Following
- 3How can I produce iron powder with minimum particle size and maximum purity?
How can I produce iron powder with minimum particle size and maximum purity?
Weather it is a micro powder or nano powder...Following
- NewI am working on "Extensions of Special functions and their applications ". Is anyone interested in collaboration then most well come?
Since last 15 years, I am working on Special Functions and their applications. Recently, number of applications of special functions found in many fields. Now, I am interested in extensions of special functions?Following
- 2Could anybody please recommend the best software for modelling of surface and sub-surface deformation due to underground excavation (tunnel)?
Actually I am new in the field of modelling. I have options in software's availability i.e. Abacus or Flac3D. I am trying to model layered soft-soil and shallow tunnel/deep excavation in urban area and its effect in surface and subsurface structures.
- 2Where can I find examples of 3D time-dependent acoustic problems with analytical solutions?
I am looking for some benchmark examples for transient three-dimensional acoustic analysis.
Take a look at it can find something for yourself
1.Zieliński T.G., Normalized inverse characterization of sound absorbing rigid porous media, JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA (ISSN: 0001-4966), Vol.137, No.6, pp.3232-3243, 2015
2.Zieliński T.G., Generation of random microstructures and prediction of sound velocity and absorption for open foams with spherical pores, JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA (ISSN: 0001-4966), Vol.137, No.4, pp.1790-1801, 2015
3. Nowak Ł.J., Zieliński T.G., Determination of the free-field acoustic radiation characteristics of the vibrating plate structures with arbitrary boundary conditions, JOURNAL OF VIBRATION AND ACOUSTICS-TRANSACTIONS OF THE ASME (ISSN: 1048-9002), Vol.137, pp.051001-1-8, 2015
4. Zieliński T.G., Microstructure-based calculations and experimental results for sound absorbing porous layers of randomly packed rigid spherical beads, JOURNAL OF APPLIED PHYSICS (ISSN: 0021-8979), Vol.116, No.3, pp.034905-1-17, 2014
more you can find here:
I hope that you would help
- 2Is the preperation of binary and ternary semiconductors of type II-IV feasible in a laboratory environment?
actually the Ar envoirment needed for their preperation is currently not available .
All right sir!Following
- 1What is the basic principle for choosing solvents for GC-MS analysis?
Do the samples used for GC-MS analysis vary according to the compounds to be analysed? What if one is not sure of the compounds formed?
It is as simple as the compounds that you want to separate and identify being soluble in the solvent. Generally low boiling solvents, such as hexane or methanol, are used as they move rapidly through the column. In many analyses, the MS detector is turned off for some time after the injection to allow the solvent to move through the column. The detector can then be turned on.Following
- NewHow to start accounting and auditing research as beginner?
I am the fresh Ph.D student and I need your help and tips, how I will start my accounting and Auditing research?
- NewHow can I build a regional multiplier based in input-output tables?
We are analysing the economic impact of local farmer's market in the Basque Country (Spain), adapting SEED methodology developed by Loyola University of New Orleans. Our region has updated the input-output data, but we would need to calculate the regional multiplier to estimate the impact of the markets over the regional economy.Following
- NewWould you discuse the dependence of mechanical properties on the defects of crystal?
Helen Abdolahifar ,Choubani Mohsen and Gopal AnugulaFollowing
- 5Is it necessary to run stationary (panel unit root) test for panel data?
Is it necessary to run stationary (panel unit root) test for panel data? When the T =30years and N =15.
thank you all for your response.Mohd Adib Ismail sir i have a doubt. which test i have to do for unit root. The Levin-Lin (LL) Tests,The Im-Pesaran-Shin (IPS) Test ??? or ADF test ?? please guide me in this. for FIXED AND RANDOM EFFECT models.
what about panel corrected standard error model? is it GLS random?
i need guidance on panel unit root test procedure.Following
- 5What are the research parameters of river water quality analysis?
Generally we use WQA for drinking water using WHO standard or national water quality indexes. Some countries also following river water quality analysis as per plankton, algae, benthos and invertebrates (aquatic flora and fauna. Fish species and their feeding ground would be the another parameter we can assume for WQA. Besides these what are the scientific standard as we can use the best method for river water quality analysis?
It depend on your goal. If you are thinking about just to know pollution measuring BOD, COD, DO are important, but if you are thinking the quality of water for consumption for example drinking water usually EC and.. are important.Following
- 2Are there any commercial hLESC (human Limbal Epithelial Stem Cells) lines?
I am looking for a commercial cell line of human LESCs. I can't find any.
Do you look at these addresses ?
ATCC Cell Lines
UK Stem Cell Bank
- NewHow effective is emotion in career building?
Do you believe that emotion triggers determination?Following
- NewWhat does the Prediction Model error function mean?
I am solving a prediction problem where I am supposed to predict the number of clicks, given some historical Data. I am told that my predictions will be evaluated by a normalized weighted mean square error which can be seen on the attached image.
My question is, why do we need to normalize error function?
Can some please explain, what the function is doing actually?
Thank you in advance.Following
- 96How do the economists define self-interest and rationality?
How do the economists define self-interest and rationality so as to make these concepts different from the animal instincts, beast behaviour, and barbarism? What is that which forms and what is that which does not form the self-interest? Moreover, are these the behavioural guides for all individuals? Are these the collective guides for policy making?
Given the propensity for free riding in each economic-beast, does not the collective policy results into a collective free riding of those who make policies over those who do not?
If you don't like my proposal for the two Georgist axioms, perhaps this will make more sense. Hillel the Elder (about 10 years CE., asked 3 questions:
1. If I am not for myself, who will be for me?
2. But being for myself alone, what am I?
3. And if not now, when?
This introduces an element of altruism into the explanation of the nature of ourselves, but surely it has no connection with how our society works, or does it?Following
- 1How can the leishman stain be modified to demonstrate the stipplings in the P. vivax and P. ovale?
The best stain method for malaria is Giemsa and to demostrate the dots is necessary to stain more time at least 30minutes.Sometimes it is necessary to test differents staining time. Giemsa is also used for leishmania stain.Following