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31.
Huang Mcngcai Gu Zhong Hang Wenjing Zhong Quan Research Section of Biophysics Biomedical Engneering Tang Fuyong Suzhou Electrical Power School 《苏州大学学报(医学版)》1990,6(2):187-194
Describe some new fully automatic instruments for the measurements of the blood capillary pressure (Pcap) and arterial elastic properties in human fingers using a photoelectric plethysmographic technique. With these instruments, the value of Pcap was in good agreement with those reported by other investigators, the arterial elastic properties in human fingers have been successfully measured. The measurements of Peap and arterial elasticity are now required in clinics because they provide useful and important information for evaluating vascular haemodynamics. 相似文献
32.
Effect of stoichiometry and Cu-substitution on the phase structure and hydrogen storage properties of Ml-Mg-Ni-based alloys
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To improve the electrochemical properties of rare-earth-Mg-Ni-based hydrogen storage alloys, the effects of stoichiometry and Cu-substitution on the phase structure and thermodynamic properties of the alloys were studied. Nonsubstituted Ml0.80Mg0.20(Ni2.90Co0.50-Mn0.30Al0.30)x (x=0.68, 0.70, 0.72, 0.74, 0.76) alloys and Cu-substituted Ml0.80Mg0.20(Ni2.90Co0.50-y Cuy Mn0.30Al0.30)0.70 (y=0, 0.10, 0.30, 0.50) alloys were prepared by induction melting. Phase structure analysis shows that the nonsubstituted alloys consist of a LaNi5 phase, a LaNi3 phase, and a minor La2Ni7 phase; in addition, in the case of Cu-substitution, the Nd2Ni7 phase appears and the LaNi3 phase vanishes. Thermodynamic tests show that the enthalpy change in the dehydriding process decreases, indicating that hydride stability decreases with increasing stoichiometry and increasing Cu content. The maximum discharge capacity, kinetic properties, and cycling stability of the alloy electrodes all increase and then decrease with increasing stoichiometry or increasing Cu content. Furthermore, Cu substitution for Co ameliorates the discharge capacity, kinetics, and cycling stability of the alloy electrodes. 相似文献
33.
ZHENG Quan 《系统科学与复杂性》1992,(4)
This paper is concerned with applications of integrated semigroups tothe following Cauchy problem:(ACP_n) x~(n)(t)=sum from i=0 to n-1 B_ix~(i)(t),x~(i)(0)=x_i,0(?)i(?)n-1where B_i (0(?)i(?)n-1) are closed linear operators on a Banach space X.Auniqueness theorem,a condition of the solvability,a condition of the exponentialwell-posedness,and some results for the special case that B_(n-1) is bounded andD(B_(n-2))(?)D(B_i)(0(?)i(?)n-3) are obtained. 相似文献
34.
The formation mechanism of the cold-rolled strip shape with high tension was studied. An advanced method to calculate the allowable variation of strip transverse profiles was established by the strip buckling criterion, which can be more properly used in cold rolling. With this method, the aim allowable variation of the product strip transverse profile and the required transverse profile range of incoming strips can be reached. Besides, this method has been successfully applied in a domestic tandem cold mill, and the transverse profile range of incoming strips suggested with this method is more practicable and complete. Consequently, the good performance is acquired. 相似文献
35.
THE M/M/c QUEUE WITH PH SYNCHRONOUS VACATIONS 总被引:6,自引:0,他引:6
TIAN Nai shuo 《系统科学与复杂性》2000,(1)
1.IntroductionRecently,singleserverqueueswithvacationshavebeenstudiedextensivelyfromtheirowntheoreticalinterestaswellastheirapplicationstomanyengineeringsystemssuchascomputers,communicationnetworksandmanufacturingsystems.FOrtheM/G/lqueueingsystemswit... 相似文献
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37.
ZHOU Chongwen ZHU Quan FU Kexiang LI Xiangyuan 《科学通报(英文版)》2006,51(8):902-905
Electron transfer (ET) is an elementary process in redox reactions, and it has been intensively studied for decades. The ET complexes in which the 7,7,8,8-tetra- cyanoquinodimethane (TCNQ) acts as the electron acceptor, whereas Cu, Ag, etc. as the electro… 相似文献
38.
ZHU Quan LIU Jifeng FU Kexiang HAN Keli LI Xiangyuan 《科学通报(英文版)》2006,51(24):2951-2958
By introducing the concept of spring energy of permanent dipole and taking the conforma-tions of solvent molecules into account,the formulas of electrostatic solvation energy in equilibrium and nonequilibrium are derived from the explicit solvent scheme,with the spatial distribution of the discrete permanent charges and induced dipoles of the sol-vent molecules involved. The energy change of sol-ute due to the variation of wave function from the case of vacuum to that in solution is estimated by treating the solvent effect as external field in the it-eration cycles of the self-consistent field. The ex-pression for spectral shift is deduced and applied to the processes of light absorption and emission in solution. According to the new formulations,the av-eraged solvent electrostatic potential/molecular dy-namics program is modified and adopted to investi-gate the equilibrium solvation energy of water mole-cule and spectral shift of acrolein. 相似文献
39.
Zhang Yinan~ Sun Qingwei~ Quan He~ Jin Yonggao~ & Quan Taifan~ . Dept. of Electronics Communication Engineering Harbin Inst. of Technology Harbin P. R. China . Mobile Communications Corporation of China Harbin P. R. China . Dept. of Electronics Information Engineering of Yanbian Univ. Yanbian P. R. China 《系统工程与电子技术(英文版)》2006,17(3):495-501
1 .INTRODUCTION Under increasingly complex operational circumstances ,there exists uncertain information in the sensors andthe networks of the multi-sensor system. The uncer-tainty occursin various manners ,e.g.the uncertaintyof multi-sensor systemstructure (includingthe dynam-ic ti me-variation property) and the uncertainty of theinformationitself (including fuzziness (containing am-biguity) ,randomness ,incompleteness (including de-fectiveness) as well as roughness) . And uncertainin-for… 相似文献
40.
Zhao Bin Quan Taifan & Wang JinrongResearch Institute of Electronic Engineering Harbin Institute of Technology Harbin P. R. China 《系统工程与电子技术(英文版)》2005,16(1)
1.INTRODUCTION InMMWradar,steppedfrequencysignalisoften chosentobetheemissionwaveform,andthetarget scatteringpropertiescanbedescribedasmultiscatter ingcenters.Modernspectrumanalysiscanimprove therangeresolution,butitneedscomplexsignal modeling,sufficientSNRandheavycomputation. Becauseofthegoodpropertiesoftime frequencylo calizationandapproximation,wavelettheoryhasbeen widelyappliedintotheimagingoftargetrangeprofile inthefieldofhighresolutionradar.InRefs.[1,2] thewaveletanalysisisperf… 相似文献