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131.
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
132.
Using a cavity perturbation technique, dielectric properties of aqueous solutions of α-
-glucose at 915 MHz were investigated at concentrations varying from 10 to 70% (w/w) and temperatures ranging from 25–85°C. The dielectric constant increased with temperature but decreased with concentration, whereas the loss factor did the inverse. Dielectric properties for higher concentration glucose solutions showed the greatest variation at higher temperatures. Predictive models of the dielectric properties as functions of concentration and temperature were developed by stepwise regression. Such models are useful in estimating the volumetric heating of these solutions by microwave energy, studying the dielectric behavior of the glucose solutions, and chemical reactions involving glucose in aqueous solutions in a microwave field. 相似文献
133.
The following result is proved: If A and B are distinct n × n doubly stochastic matrices, then there exists a permutation σ of {1, 2,…, n} such that ∏iaiσ(i) > ∏ibiσ(i). 相似文献
134.
135.
S. Lal R. Raghavan T. N. Rangaswamy B. V. Sreekantan A. Subramanian 《Proceedings Mathematical Sciences》1971,73(5):213-222
Using a combined set-up of a multiplate cloud chamber, an air Cerenkov counter and a total absorption spectrometer, the ratio of pions to protons not associated with large air showers has been determined to be 0·50 ± ·07 in the energy region 20–40 GeV at an altitude of 800 gm/cm2. In the same energy region the ratio of neutral to charged particles is found to be 0·66 ± ·07. From the ratio of neutrons to protons deduced from these measurements (i.e., 0·99 ± ·11), it is concluded that most of the charge excess of nuclear active particles of energies > 20 GeV at mountain altitudes and sea-level is due to pions. 相似文献
136.
137.
The Wacker-type oxidation is an important procedure catalyzed by palladium complexes. A mild and general method for the preparation of β-substituted-δ-oxosulfoxides from the corresponding β-substituted-γ,δ-unsaturated sulfoxides is described. The products are versatile synthetic intermediates for the preparation of syn- and anti-1,3-diol and 1,3-aminoalcohol derivatives. 相似文献
138.
139.
Telmisartan (anti-hypertensive) is insoluble in water; hence the drug may be slowly or incompletely dissolved in the gastro intestinal tract. So the rate of dissolution and therefore its bioavailability is less (bioavailability 42%). In the present study an attempt has been made to prepare immediate release tablets of telmisartan by using Polyplasdone XL-10 (Crosspovidone) at intragranular, extragranular and partly intra and extragranular level of addition to increase the rate of drug release from dosage form to increase the dissolution rate and hence its bioavailability. The prepared granules and tablets were evaluated for their physiochemical properties and in-vitro dissolution study was conducted for the prepared tablets. It was concluded that the immediate release tablets with proper hardness, disintegration time and with increase rate of dissolution can be made using Polyplasdone XL-10. Formuation-10 (F10) was selected for stability study and the in-vitro dissolution study showed that was no difference in percent of drug released between initial and sixth month sample. 相似文献
140.
Michael addition reactions of bis(amino acidato)metal(II) complexes (metal = copper, nickel, zinc; amino acid = glycine, dl-alanine, l-alanine) with acrylonitrile have been carried out under various experimental conditions in the absence of a base, resulting in mono- and disubstituted products in high yield, including partially hydrolyzed products. A reaction mechanism for the Michael addition on the nitrogen atom of the coordinated amino acid moiety, replacing the amino hydrogen atom(s), is proposed. All of the products have been characterized by Fourier transform infrared spectroscopy, electron paramagnetic resonance spectra, and elemental and electrochemical analyses. The single-crystal structures of bis( N-cyanoethylglycinato)copper(II) monohydrate ( 1a), diaquabis( N-cyanoethylglycinato)nickel(II), aquabis( N, N-dicyanoethylglycinato)copper(II) ( 2a), and bis[( N-propionamido- N-cyanoethyl)glycinato]copper(II) dihydrate ( 4a) have been confirmed by X-ray diffraction techniques. The products 1a, 2a, 4a, and bis( N-propionamidoglycinato)copper(II) monohydrate ( 3a) have been used as catalysts for the degradation of a phenol red dye and mild oxidation of various organic substrates in the presence of hydrogen peroxide. The monosubstituted complexes have been found to catalyze the reactions to a greater extent than the disubstituted complexes. 相似文献