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101.
Z. Shi 《Journal of Theoretical Probability》1996,9(4):915-929
LetR be the radial part of ad-dimensional Wiener process, starting from 0. In this paper, small ball probabilities are evaluated for sup0<11(t
–p
R(t)) and sup
t
0(e
–1
R(t)), withp[0, 1/2]. Chung's law of the iterated logarithm is established for the supremum of the local times of a two-dimensional Bessel process. 相似文献
102.
Peter Graneau 《Foundations of Physics Letters》1993,6(5):491-500
This paper discusses a new turn in the 148-year old electrodynamic force law controversy between the 1822 Ampère force law of the Newtonian electrodynamics and Grassmann's 1845 law which has become the electrodynamic force law of relativistic electromagnetism. Faced with the infallibility of Ampère's empirical law, defenders of relativity theory now argue that Ampère's law is equivalent to the relativistic law. This paper demonstrates that, far from being equivalent, the laws require two different mechanics of solid bodies, disagree on internally generated stresses, and predict different force distributions. 相似文献
103.
Transient propagation of weak pressure perturbations in a homogeneous, isotropic, fluid saturated aquifer has been studied. A damped wave equation for the pressure in the aquifer is derived using the macroscopic, volume averaged, mass conservation and momentum equations. The equation is applied to the case of a well in a closed aquifer and analytical solutions are obtained to two different flow cases. It is shown that the radius of influence propagates with a finite velocity. The results show that the effect of fluid inertia could be of importance where transient flow in porous media is studied.List of symbols
b
Thickness of the aquifer, m
-
c
0
Wave velocity, m/s
-
k
Permeability of the porous medium, m2
-
n
Porosity of the porous medium
-
p(
,t)
Pressure, N/m2
-
Q
Volume flux, m3/s
-
r
Radial coordinate, m
-
r
w
Radius of the well, m
-
s
Transform variable
-
S
Storativity of the aquifer
-
S
d(r, t)
Drawdown, m
-
t
Time, s
-
T
Transmissivity of the aquifer, m2/s
-
(
,t)
Velocity of the fluid, m/s
-
Coordinate vector, m
-
z
Vertical coordinate, m
-
Coefficient of compressibility, m2/N
-
Coefficient of fluid compressibility, m2/N
-
Relaxation time, s
-
(r, t)
Hydraulic potential, m
-
Dynamic viscosity of the fluid, Ns/m2
-
Dimensionless radius
-
Density of the fluid, Ns2/m4
-
(, )
Dimensionless drawdown
-
Dimensionless time
-
, x
Dummy variables
-
0,
1
Auxilary functions 相似文献
104.
用新颖的干粉方法合成系列沸石的研究已从五元环沸石延伸到具有四元环和六元环的方钠石。本研究运用干粉方法在Na2O-SiO2-Al2O3混合物中分别以乙醇胺和乙二胺-氟化物为模板,合成出了方钠石。有机模板剂以吸附态模板方式进入体系。用XRD数据、扫描电镜图及红外光谱测试结果对实验产品做了表征。结果表明,干粉体系制备的方钠石的晶胞参数小于水热体系和非水体系合成的方钠石的相应值。而以乙醇胺为模板制备的方钠石与以乙二胺-氟化物为模板的样品比较,后者具有较快的晶化速度、较小的晶胞体积和晶粒 相似文献
105.
Ramón Puyané Isabelle Guy Renaud Metz 《Journal of Sol-Gel Science and Technology》1998,13(1-3):575-578
The ceramic microstructure, the chemical homogeneity of specific dopants and the mechanical integrity of a varistor disc are critical parameters in determining the transient voltage suppression features of these devices. The material properties and overall quality of the starting ceramic powders used to produce such components are essential in achieving the desired properties. The present work describes a novel chemical method developed to produce doped zinc oxide powders and an industrial scale manufacturing process for the production of final varistor blocks for surge arrester applications. The results are compared with those obtained when using standard varistor powder made by the mixed oxide route is used. All the fundamental electrical properties of the discs have been determined and correlated with the relevant manufacturing steps. 相似文献
106.
On the basis of copper sulphate pentahydrate thermal dissociation, for analyzed reactions I to IV, 6 thermokinetic equations was discussed. Arrhenius law parameters were determined and the isokinetic effect (IE) and Kissinger law appearing was analyzed. It was found that only dependence resulting from isokinetic effect, in the form k
m=q/T
m, relates to the suitable thermokinetic Eq. (2) and Kissinger law in modified form (14). The confirmation was made that the possibility of determining the averaged activation energy from thermokinetic equations using suitable correction coefficients exists.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
107.
IntroductionZeoliteZSM-35isclassifiedasfcrricritc(FER)t\pc.x'hicllalsoincludesZSM-ZI.ZSM-38andFER.Zeolitesofthist}'pcha\lcrclatit'CI}UlldiscrinlinablcXRDpattcnlswhichindicatetheirsinlilarit\'illst,u.tu,.,I11.Thehighsiliceousfonllsofthesezeolitesarcgcllcra… 相似文献
108.
From conductance and viscosities measurements on Pr4NCl, Et4NBr, and AgNO3 in acetonitrile and Et3NBr in nitrobenzene, the Walden products of the anion at infinite dilution were determined in presence of various concentrations of substituted benzoic acids. From these data it was possible to compute the values of the Walden products of the once complexed anions and to estimate the order of magnitude of the Walden products of twice complexed anions. Stokes' law is not obeyed, and the Walden products are not proportional to the third root of the molar volume of the complexed ions, as a consequence of their lack of sphericity. The assumption that the drag force which acts on the ions is proportional to the volume of the substituents results in a linear expression between the reciprocals of the Walden products and the molar volume of the ligands. The experimental results fit this expression within the limits of the experimental errors, and the slopes of the lines are nearly the same for all the anions and for the two solvents studied here, namely, 2.5×10–4 ohm-cm–5 mole-cP–1. 相似文献
109.
Mavroudis A Demertzis 《Analytica chimica acta》2004,505(1):73-76
An efficient, more sensitive and accurate spectrophotometric process is possible and can be used to obtain qualitative or quantitative results for analytes at limiting concentrations lower than usual. Transmission measurements (incident light power, P0, or transmitted, P) are performed with a fluorescence spectrometer. One cell only is used to measure standards or unknown solutions, placed between the standard holder cuvette and the emission monochromator of the instrument. The source of the radiant power (P0) is not the xenon lamp but the fluorescence or scattered radiation from the holder cuvette filled with an appropriate solution. The analyte concentration is found from a calibration graph, based upon Beer’s law or the approximate formula P0−P=2.303P0εbc, which is valid for dilute solutions. Determination of iron in a reference material, using 1,10-phenanthroline as the chromogenic reagent, was chosen as an example to demonstrate the suitability of the proposed method and clarify several important statistical questions. Also discussed is why and to what extent molecular fluorescence methods are more sensitive than molecular absorption methods. 相似文献
110.