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1.
2.
Utility of toroidal shells as shock absorbers for radioactive materials' shipping casks is discussed by carrying out numerical and experimental analyses. The static load-deflection relations under axisymmetric compression between rigid plates are presented.A simple elastic-plastic analytical method is first developed on the basis of an incremental Rayleigh-Ritz method by taking account of the large deflections and the continuous change of contact points. Meridional compression is neglected and the meridional curvature distribution is approximated by a trigonometric series. Strain-hardening material properties and axisymmetric deformation are also assumed. In order to provide data for comparison purposes, static compression tests were performed using six models of different shapes and dimensions made of 304-type stainless steel. Finally, the applicability of the numerical method developed in this paper is discussed.The mechanical behavior of toroidal shells is also discussed.  相似文献   
3.
Deposition rate dependence of perpendicular coercivity Hcl in Cocr evaporated films at the deposition rate ranging from 0.4nm/s to 400nm/s is studied. Hcl increases with decreasing deposition rate as well as with increasing substrate temperature. A High Hcl over 500 Oe, which has ever been obtained only at a substrate temperature over 250°C when deposition rate is high(400nm/s), is obtained at a substrate temperature of 150°C under deposition rate of 2nm/s. "Shoulder" in the hysteresis loop disappears as Hcl exceeds 400 Oe. Therefore to decrease the deposition rate and to increase the substrate temperature have the same effect on Hcl. Saturation magnetization of the films with the same Cr concentration increases with decreasing deposition rate, and it is suggested that the degree of Cr segregation increases with decreasing deposition rate. Hcl is independent of the background pressure when the relative pressure, the quotient of (background pressure/deposition rate), is between 2×10-8and 5×10-6torr/(nm/s). From the results above, it is clarified that the difference of deposition rate between vacuum evaporation and sputtering is one of the major reasons for the difference of Hcl between the two.  相似文献   
4.
Shizuo Sugita 《Desalination》1975,17(3):231-237
Electrodialysis with ion-exchange membranes is one of the most important methods of desalination and salt manufacture. Prevention of scale formation in dialysis cells and evaporators is one of its main problems.This paper discusses the formation of alkaline scale during the process of heating and concentrating brine obtained by electrodialysis with ion-exchange membranes.  相似文献   
5.
Matrix (M) and nonstructural (NS) genes of thirteen equine H3N8 and H7N7 influenza viruses were sequenced and analyzed from an evolutionary point of view. The M and NS genes of H3N8 viruses isolated between 1989 and 1993 evolved into two minor branch clusters, including isolates from Europe and the American continent, respectively. It was noteworthy to reveal that the nucleotide sequences of the M and NS genes of an earlier American strain showed highest homology to those of recent European viruses. "Frozen evolution" was observed in the M and NS genes of A/eq/LaPlata/1/88. It was also evident that the NS gene of an H7N7 virus from 1977 was very similar to that of a 1979-H3N8 virus, while the M gene was closest phylogenetically to that of the earliest H7N7 virus isolated in 1956. Furthermore, the M2 protein of A/eq/Newmarket/1/77 virus contained a carboxyl terminal deletion of three amino acids. The evolutionary rates of the M and NS genes of H3N8 equine influenza viruses were estimated to be 5.4 x 10(-4) and 5.1 x 10(-4) substitutions per site per year, respectively, which were slower than those of human viruses.  相似文献   
6.
A periodically poled structure with 6.95 /spl mu/m period and 10 mm interaction length was fabricated in a 1 mm-thick 1.8 mol% MgO doped near-stoichiometric LiNbO/sub 3/ (MgSLN) by using a multi-pulse poling technique. Blue SHG characteristics of this periodically poled MgSLN were investigated, in comparison with a periodically poled 5 mol% MgO doped congruent LiNbO/sub 3/.  相似文献   
7.
We investigated prolactin (PRL) and growth hormone (GH) secretion during acute and late abstinence following methylphenidate (MP) administration. Ten male patients who were undergoing acute cocaine abstinence and nine control subjects were randomly assigned into one of two possible sequences of MP and placebo, with each experimental condition occurring on two successive days. This procedure was repeated after 7 days for the patients. Baseline measures were analyzed by analysis of variance (ANOVA) with post hoc tests. Measures of MP challenge were analyzed by analysis of covariance (ANCOVA) with baseline as the covariate. Acute abstinence was compared with control values and then to late abstinence. Plasma levels of PRL, GH, and MP were measured along with a measure of clinical symptoms. Patients had higher basal PRL concentrations during acute abstinence compared with controls, and patients showed no difference when compared to themselves after 7 days (late abstinence). Provocation with MP yielded exaggerated PRL and GH responses in patients during acute abstinence compared with control values, and ANCOVA also revealed a significant increase in PRL response during late abstinence compared with acute abstinence. GH was a less sensitive indicator than PRL. Craving was exacerbated by MP during both acute and late abstinence and was possibly increased at late abstinence. This indicates that the perturbation in dopamine regulation persists and may be increased as clinical recovery occurs for most subjective symptoms. Blood pressure changes were variable and interpretation was uncertain.  相似文献   
8.
Perpendicular anisotropy of evaporated magnetic films   总被引:1,自引:0,他引:1  
Evidence of the existence of origins of perpendicular anisotropy other than the ordinary magnetostrictive effect is presented with a brief review of other studies. As one of these origins, the effect of the grain boundaries or the microscopic shape effect is discussed. The amount of perpendicular anisotropy observed in the stripped films does not seem capable of explanation by this effect only.  相似文献   
9.
New Submicron (0.5-1.0 mum diam) bubble garnets have been developed. In order to reduce saturation induction4piMsas low as possible, suitable choice of amounts of nonmagnetic ions substituting for ferric ions in both tetrahedral and octahedral sites were studied in (YSm)3(FeAl)5O12, (YSmLu)3- (FeGaSc)5O12, (YSmLu)3(FeAlSc)5O12and (LaLuSm)3- (FeGa)5O12garnet systems. For example, in (YSmLu)3- (FeAlSc)5O12a film with the following properties was grown; strip widthw = 0.7mum, film thicknessh= 0.7mum, quality factorq=2.8, Curie temperatureTc= 140degC and4piMs=770G. The temperature properties of those films could be improved drastically by doping with a small amount of Gd ion. Wall mobilities μw of those films are in the region from 200 to 500cm/s/Oe. Preceding these material studies, several film characterization methods have been investigated. Film thickness was measured by Fluorescent X-ray method, strip width by using a highly sensitivity TV camera, and bubble collapse field by FMR resonance technique respectively.  相似文献   
10.
The authors have been working on natural language understanding based on the knowledge representation language L md and its application to robot manipulation by verbal suggestion. The most remarkable feature of L md is its capability of formalizing spatiotemporal events in good correspondence with human/robotic sensations and actions, which can lead to integrated computation of sensory, motory and conceptual information. This paper describes briefly the process from text to robot action via semantic representation in L md and the experimental results of robot manipulation driven by verbal suggestion. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008  相似文献   
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