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171.
Ultra heavy (UH) cosmic rays of Z65 are produced either by s- or r-process of nucleosynthesis. Since these two processes occur under different astrophysical environments, the relative abundances of UH ions could be an important parameter in finding their source and origin. Data analysis is carried out on four detector stacks exposed in space by UH cosmic ray experiment on board LDEF. Scanning and analysis of 0.21 m2 detector area resulted in finding of 72 UH ions (68Z96) including two actinides (88Z100). The ratio of actinides to that of sub-actinides is found to be 0.034±0.024, which is well within the observational limits of other experiments. Results suggest possible sources, which predominantly ejects r-process synthesized material. 相似文献
172.
For a helical body made of a linear piezoelectric material and loaded at one end only by a system of self-equilibrated forces, it is shown that the strain energy stored in the part of the body distant at least s from the loaded end decreases exponentially with the distance s. 相似文献
173.
174.
We study infinitesimal deformations of a porous linear elastic body saturated with an inviscid fluid and subjected to conservative surface tractions. The gradient of the mass density of the solid phase is also taken as an independent kinematic variable and the corresponding higher-order stresses are considered. Balance laws and constitutive relations for finite deformations are reduced to those for infinitesimal deformations, and expressions for partial surface tractions acting on the solid and the fluid phases are derived. A boundary-value problem for a long hollow porous solid cylinder filled with an ideal fluid is solved, and the stability of the stressed reference configuration with respect to variations in the values of the coefficient coupling deformations of the two phases is investigated. An example of the problem studied is a cylindrical cavity leached out in salt formations for storing hydrocarbons. 相似文献
175.
Shashikant U. Dighe Sushobhan Mukhopadhyay Shivalinga Kolle Dr. Sanjeev Kanojiya Sanjay Batra 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(37):11076-11080
An efficient NaNO2/I2‐mediated one‐pot transformation of Morita–Baylis–Hillman (MBH) acetates into alkyl 3‐nitro‐5‐(aryl/alkyl)isoxazole‐4‐carboxylates is described. In a cascade event, initial Michael addition of NaNO2 to the MBH acetate furnishes the allylnitro intermediate which undergoes I2‐catalyzed oxidative α‐C H nitration of the nitromethyl subunit followed by [3+2] cycloaddition to afford the title compounds. Structural elaborations of these highly substituted isoxazoles by SNAr reactions and hydrogenolysis allows access to useful products. 相似文献
176.
Jitka Dostálková Gita Procházková Vladimír Jirků Lucie Křiklavová Tomáš Lederer Miloslav Suchánek Tomáš Brányik 《Chemical Papers》2015,69(3):425-432
This paper focuses on the adhesion and biofilm formation potential of cellulolytic yeast Trichosporon cutaneum CCY 30-5-10 on solid cellophane from a novel perspective. First, physicochemical characterisation of the cells and carrier (cellophane) was performed to evaluate the effect of different culture media (complex vs mineral) on yeast cell adhesion. (Un)favourable adhesion conditions were predicted using the thermodynamic approach. Next, the ability of the cells to colonise the carrier under the above conditions was quantified and the biofilm structure was characterised using image analysis. The approaches described were found suitable to predict and experimentally verify favourable (cell-solid) adhesion, i.e. the hydrophobic and low electron-donor nature of cellophane together with hydrophobic cells (obtained when cultivated in a complex culture medium) were found to have a major impact in defining successful yeast adhesion with subsequent biofilm formation. 相似文献
177.
R. C. Batra 《Journal of Elasticity》1983,13(2):165-173
Toupin's version of the Saint-Venant principle in linear elasticity is generalized to the case of linear elasticity with microstructure. That is, it is shown that, for a straight prismatic bar made of an isotropic linear elastic material with microstructure and loaded by a self-equilibrated force system at one end only, the strain energy stored in the portion of the bar which is beyond a distance s from the loaded end decreases exponentially with the distance s. 相似文献
178.
We use a semi-inverse method to study deformations of a straight, prismatic, homogeneous body made of a porous, linear elastic,
and isotropic material and loaded only at its end faces by self equilibrated forces. As in the classical theory, the problem
is reduced to solving plane elliptical problems. It is shown that the Clebsch/Saint-Venant and Voigt hypotheses are not valid
for this problem.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
179.
R.C. Batra 《Journal of Elasticity》1998,51(3):243-245
For simple shearing and simple extension deformations of a homogeneous and isotropic elastic body, it is shown that a linear
relation between the second Piola-Kirchhoff stress tensor and the Green-St. Venant strain tensor does not predict a physically
reasonable response of the body. This constitutive relation implies that the slope of the curve between an appropriate component
of the first Piola-Kirchhoff stress tensor and a deformation measure is an increasing functions of the deformation measure.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
180.
Priyanka Jhajharia Mahesh Kumar Samota Kusum Soni Gita Seth 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):315-321
The synthesis, biocidal activity, and spectroscopic data of a new series of S-phosphorylated/thiophosphorylated derivatives of 2-(2′-mercaptophenyl) benzothiazole are reported in this study. Derivatives were prepared by reacting 2-(2′-mercaptophenyl) benzothiazole with phosphorus oxychloride/phosphorus thiochloride in different molar ratios [1:1, 2:1, 3:1]. All of the derivatives were found to be antifungal agents with less toxicity than the standard Dithane M-45. 相似文献