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101.
The SAMPEX (Solar, Anomalous, and Magnetospheric Particle Explorer) LEICA instrument is designed to measure ~0.5-5-MeV/nucleon solar and magnetospheric ions over the range from He-Ni. The instrument is a time-of-flight (TOF) mass spectrometer, which measures particle TOF over an ~0.5-m path and the residual energy deposited in an array of Si solid state detectors. Large-area microchannel plates are used, resulting in a large geometrical factor for the instrument (0.6 cm2 sr), which is essential for accurate compositional measurements in small solar flares and in studies of precipitating magnetospheric heavy ions  相似文献   
102.
This study examined the hypolipidemic effect of 4 weeks of L-carnitine treatment (170 mg/kg b.w./day) in New Zealand White rabbits fed a high fat diet (5% corn oil/0.5% cholesterol). Specifically, [3H] glycerol and [125I] very low density lipoprotein (VLDL) turnover studies were conducted to examine the effect of treatment on VLDL kinetics. The masses of plasma VLDL-triglycerides (VLDL-TG) and VLDL-apoprotein B (VLDL-apoB) were significantly increased by the high-fat diet. Four weeks of treatment with L-carnitine significantly reduced these masses. Kinetic analysis indicated that fat feeding reduced the fractional catabolic rates (FCRs) of VLDL-TG and VLDL-apoB relative to chow-fed controls. The transport of these VLDL components was not altered by the diet. L-carnitine treatment had no effect on the FCRs of VLDL-TG and VLDL-apoB or on the transport of VLDL-apoB. Yet, treatment significantly lowered the transport of VLDL-TG. These data indicate that the lipid-lowering effect of L-carnitine in this animal model was due, in part, to a decrease in the transport and not due to an alteration in the fractional catabolic rate of VLDL-TG.  相似文献   
103.
空冷发电厂的热力设计与分析   总被引:1,自引:1,他引:0  
本文对热力发电厂的汽轮机排汽冷却系统进行了评估。作者编制了计算机程序,并对海勒式空冷系统做了计算,结果显示了塔高、水流速与空气流量、冷却塔与散热器投资以及经济效益的关系。  相似文献   
104.
105.
Nitrogen addition to iron powder by mechanical alloying   总被引:3,自引:0,他引:3  
Nitrogen was alloyed into iron (a) by mechanical processing in a nitrogen gas environment, and (b) by mechanically alloying with iron-nitride powders to characterize resulting nano-structure and nitrogen distribution. Although the infused nitrogen concentration was significantly greater than the thermodynamic equilibrium solubility of iron, no nitrides formed, even for nitrogen concentrations as high as 4.1 wt.% However, a bctFe phase did form. Lattice expansion calculations indicate that the sum of the interstitial bcc-Fe and bctFe nitrogen concentrations was significantly less than the total measured nitrogen concentration. A considerable portion of the mechanically infused nitrogen was determined to be associated with nanograin boundaries.  相似文献   
106.
The error dynamics of the extended Kalman filter (EKF), employed as an observer for a general nonlinear, stochastic discrete time system, are analyzed. Sufficient conditions for the boundedness of the errors of the EKF are determined. An expression for the bound on the errors is given in terms of the size of the nonlinearities of the system and the error covariance matrices used in the design of the EKF. The results are applied to the design of a stable EKF frequency tracker for a signal with time-varying frequency.This research was supported by the Co-operative Research Centre for Robust and Adaptive Systems ((CR)2 ASys). The authors wish to acknowledge the funding of the activities of (CR)2 ASys by the Australian Commonwealth Government under the Co-operative Research Centre Program.  相似文献   
107.
Discusses issues and interventions for working with adolescents who live in stepfamilies. A developmental perspective, using psychoeducation and brief strategic intervention approaches, is proposed for working with stepfamilies. Six major issues for adolescents in stepfamilies are discussed: developmental issues, sexuality issues, parent–child relationships, parenting in stepfamilies, nonresidential parent–child issues, and changes in visitation and custody. Case illustrations and suggested interventions are presented for each of these areas. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
108.
Post-harvest loss of resources to microbial competitors affects a number of species of animals, and many of them have evolved behaviors that reduce the likelihood of such loss. We previously described the inhibition ofBacillus psychrophilus by dogwood fruits (Cornus drummondii), which can comprise a significant portion of the winter food cache of the eastern woodrat (Neotoma floridana). The present study is a further investigation of the ability of dogwood fruits to inhibit growth ofB. psychrophilus. Additionally, we tested the antimicrobial activity of dogwood fruits onEscherichia coli andStaphlococcus aureus. Results of our study indicate that fresh fruits inhibit the growth ofB. psychrophilus andS. aureus but notE. coli. However, fruits taken from woodrat dens after four and six months storage inhibited growth of all three species of bacteria. Further, the strength of inhibition increased over the test period. We suggest the presence of an inhibitor allows woodrats to compete effectively for a valuable and limited food resource.  相似文献   
109.
Despite its empirical and normative strengths, the underlying conceptual base of the Comprehensive Rorschach System at times lacks clarity and an overarching theory of personality that can help psychodiagnosticians make more clinically relevant inferences. After reviewing the functions provided by an integral theory of personality, the author focuses on the Experience Actual:Experienced Stimulation (EA:es) index as a way of demonstrating how mechanistic jargon and lack of a guiding theory and conceptual clarity can lead to misleading and contradictory inferences. Case examples are provided, and some of the empirical foundations of the EA:es index are reviewed. The author concludes by offering recommendations on ways in which the Comprehensive System can become more sensitive in its appearance to capturing the complexities of personality functioning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
110.
Used in concert with the Kirchhoff transformation, implicit differentiation of the discretized boundary integral equations governing the conduction of heat in solids with temperature dependent thermal conductivity is shown to generate an accurate and economical approach for computation of shape sensitivities. For problems with specified temperature and heat flux boundary conditions, a linear problem results for both the analysis and sensitivity analysis. In problems with either convection or radiation boundary conditions, a non-linear problem is generated. Several iterative strategies are presented for the solution of the resulting sets of non-linear equations and the computational performances examined in detail. Multi-zone analysis and zone condensation strategies are demonstrated to provide substantive computational economies in this process for models with either localized non-iinear boundary conditions or regions of geometric insensitivity to design variables. A series of non-linear example problems is presented that have closed form solutions. Exact anaytical expressions tor the shape sensitivities associated with these problems are developed and these are compared with the sensitivities computed using the boundary element formulation.  相似文献   
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