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1.
The time delay experiment proposed by I.I. Shapiro in 1964 and conducted in the seventies was the most precise experiment
of general relativity until that time. Further experimentation has improved the accuracy level of both the time delay and
the light deflection experiments. A simulation model is proposed that involves only a simple mass and time transformation
factor involving velocity of light. The light deflection and the time delay experiments are numerically simulated using this
model that does not use the general relativistic equations. The computed values presented in this paper compare well with
recent levels of accuracy of their respective experimental results. 相似文献
2.
A high performance liquid chromatographic (HPLC) method is described for the determination of the four major aflatoxins, B1, B2, G1 and G2, in peanut products. The aflatoxins are extracted by adapting a procedure developed by Pons (1) at the SRRC, USDA, and quantitated utilizing a new 5 mum reverse-phase column with NaCl/acetontrile/methanol mobile phase (3 + 1 + 1). The 5 mum column achieved baseline resolution of each of the four aflatoxins. Retention times and peak heights were reproducible. The procedure was successfully applied to several types of peanut products and was applicable to both roasted and unroasted peanuts, which is a decided advantage over the current CB and BF extraction methods. Additionally, it can be used for sweetened peanut matrixes with no interferences in the chromatography. The total time required for sample preparation and aflatoxin determination is less than 1.5 hours. 相似文献
3.
Ortiz O Vidyasagar A Wang J Toomey R 《Langmuir : the ACS journal of surfaces and colloids》2010,26(22):17489-17494
Near-the-surface instabilities with a cusplike morphology were observed in ultrathin photo-cross-linked poly(N-isopropylacrylamide) coatings upon swelling in water. The characteristic wavelength of the instability was approximately 25 times the dry thickness and scaled linearly with coating thickness between 30 and 1200 nm. Above 1200 nm, slippage of the coating along the confining substrate led to reticulated patterns with a much larger wavelength. To help interpret the origin of the instability, the coatings were also exposed to a solvent slightly worse than water (acetone) and a solvent slightly better than water (isopropanol). In all cases, the characteristic wavelength scaled linearly with respect to the swelling induced by each solvent. Both water and isopropanol produced well-defined cusps or folds in the gel surface, while acetone produced semiordered blisters that grew into one another. The features produced in acetone may be a consequence of swelling being close to the threshold value for the loss of planar stability. Through the use of a first-order linear perturbation of the Flory-Rehner model, it is shown that the emergence of a characteristic wavelength is consistent with an inhomogeneous distribution of solvent that results from diffusion of solvent into a dry coating. 相似文献
4.
We present two new variants of Schur complement domain decompositionpreconditioners suitable for 2D anisotropic problems. Thesevariants are based on adaptations of the probing idea, describedby Chan et al (1992 Fifth Int. Symp. on Domain DecompositionMethods for Partial Differential Equations, Philadelphia: SIAM,pp 236-249), used in conjunction with a coarse grid approximationas introduced by Bramble et al (1986 Math. Comput. 47, 103-134).The new methods are specifically designed for situations wherethe coupling between neighbouring interfaces is stronger thanthe coupling within an interface. Taking into account this strongcoupling, one variant uses a multicolour probing technique toavoid distortion in the probe approximations that appear whenusing the method proposed by Chan et al. The second techniqueuses additional probe matrices to approximate not only the couplingwithin the interfaces but also the coupling between interfacepoints across the subdomains. This latter procedure looks somewhatlike an alternating line relaxation method for anisotropic problems,see Brandt (1977 Math. Comput.. 31, 333-390). To assess therelevance of the new preconditioners, we compare their numericalbehaviour with well known robust preconditioners such as thebalanced Neumann-Neumann method proposed by Mandel (1993 Commun.Numer. Methods Eng.. 9, 233-241). 相似文献
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6.
W. A. Hamilton G. S. Smith N. A. Alcantar J. Majewski R. G. Toomey T. L. Kuhl 《Journal of polymer science. Part A, Polymer chemistry》2004,42(17):3290-3301
Polymer molecules at solid or fluid interfaces have an enormous spectrum of applications in a wide variety of technologies as lubricants, adhesion modifiers, and protective surface coatings. Because polymer brushes have great potential to be used in such applications, there is a need to determine their structure and efficiency in reduced spaces. Using neutron reflectivity, we have directly quantified the density distribution of opposing polymer brushes under confinement in good solvent conditions under confinement. Our measurements show that the density profile in the overlap region between opposing polymer brushes flattens, consistent with predictions from molecular-dynamics simulations. In addition, a significant increase in the density at the anchoring surfaces due to the collapse of the brush layers was observed. This collapse of the brushes in restricted geometries suggests that high-density brushes do not interpenetrate significantly under good solvent conditions. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 3290–3301, 2004 相似文献
7.
The ‘anomalous perihelion precession’ of Mercury, announced by Le Verrier in 1859, was a highly controversial topic for more
than half a century and invoked many alternative theories until 1916, when Einstein presented his theory of general relativity
as an alternative theory of gravitation and showed perihelion precession to be one of its potential manifestations. As perihelion
precession was a directly derived result of the full General Theory and not just the Equivalence Principle, Einstein viewed
it as the most critical test of his theory. This paper presents the computed value of the anomalous perihelion precession
of Mercury's orbit using a new relativistic simulation model that employs a simple transformation factor for mass and time,
proposed in an earlier paper. This computed value compares well with the prediction of general relativity and is, also, in
complete agreement with the observed value within its range of uncertainty. No general relativistic equations have been used
for computing the results presented in this paper. 相似文献
8.
Chaos data analysis has been performed on the chaotic output power time series data from a synchronized transmitter-receiver pair of semiconductor lasers. The system uses an asymmetric, bidirectional coupling configuration between the master (transmitter), which is a laser diode with optical feedback, and a stand-alone slave semiconductor laser. The correlation dimension of the chaotic time series has a minimum value of 4, which was obtained from high-bandwidth measurements. The correlation dimensions for both the master and the synchronized slave are identical when the cross-correlation coefficient of the synchronized chaos is above 0.9. These results establish correlation dimension analysis as an effective tool for the determination of the quality of wideband chaos synchronization. 相似文献
9.
Satheeshmanikandan RS Thappali Kanthikiran VS Varanasi Sridhar Veeraraghavan Swaroop Kumar VS Vakkalanka Mukkanti K 《Journal of mass spectrometry : JMS》2012,47(12):1612-1619
A sensitive and reliable high‐performance liquid chromatography–mass spectrometry (LC–MS/MS) was developed and validated for simultaneous quantification IC87114, roflumilast (RFM), and its active metabolite roflumilast N‐oxide (RFN) using tolbutamide as an internal standard. The analytes were extracted by using liquid–liquid extraction and separated on a reverse phase C18 column (50 mm × 3 mm i.d., 4.6 µ) using methanol: 2 mM ammonium acetate buffer, pH 4.0 as mobile phase at a flow rate 1 mL/min in gradient mode. Selective reaction monitoring was performed using the transitions m/z 398.3 > 145.9, 403.1 >186.9, 419.1 > 187.0 and 271.1 > 155.0 to quantify quantification IC87114, RFM, RFN and tolbutamide, respectively. The method was validated over the concentration range of 0.1–60 ng.mL?1 for RFM and RFN and 6 to 2980 ng.mL?1 for IC87114. Intra‐ and inter‐day accuracy and precision of validated method were within the acceptable limits of <15% at all concentrations. Coefficients of correlation (r2) for the calibration curves were >0.99 for all analytes. The quantitation method was successfully applied for simultaneous estimation of IC87114, RFM and RFN in a pharmacokinetic drug–drug interaction study in Wistar rats. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
10.
Munshi G Mustafa Sudhir Raniwala T Awes B Rai RS Bhalerao JG Contreras RV Gavai SK Ghosh P Jaikumar GC Mishra AP Mishra H Mishra B Mohanty J Nayak J-Y Ollitrault SC Phatak L Ramello R Ray PK Sahu AM Srivastava DK Srivastava VK Tiwari 《Pramana》2006,67(5):961-981
This is the report of Heavy Ion Physics and Quark-Gluon Plasma at WHEPP-09 which was part of Working Group-4. Discussion and
work on some aspects of quark-gluon plasma believed to have created in heavy-ion collisions and in early Universe are reported. 相似文献