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71.
This note derives a necessary and sufficient condition to diagonally decouple a linear multivariable system through constant gain measurement feedback. This condition is represented in terms of the controllability subspaces and the kernel of a measurement matrix. The number of assignable poles of the resulting closed-loop system is given. 相似文献
72.
73.
M Masuda R Tominaga A Nokashima H Mayumi S Morita H Kono M Hisahara K Fukae K Miyamoto Y Kawachi 《Canadian Metallurgical Quarterly》1993,46(10):845-849
Complement activation and leukosequestration to the lung was studied during cardiopulmonary bypass in eleven patients undergoing cardiac operation without blood transfusion. Six patients (group I) received methylprednisolone before and after the bypass, and the other five (group II) received cepharanthine (biscoclaurin alkaloid) before the bypass associated with methylprednisolone therapy. Leukosequestration to the lung was observed at the time of reperfusion of the lung only in group I, although complement activation estimated by the increase of C 4 a and C 3 a was quite similar in both group. Cepharanthine prevented the sequestration of the leukocyte to the lung may be by its membrane stabilizing effect. 相似文献
74.
H Pang XG Kong H Sentsui Y Kono T Sugiura A Hasegawa H Akashi 《Canadian Metallurgical Quarterly》1997,59(12):1089-1095
Six strains of equine infectious anemia virus (EIAV) were recovered from febrile and non-febrile stages of a horse experimentally infected with the P337-V70 strain given once to a horse. The env gp90 genes of the isolates, the P337-V70 and P337-V26, avirulent virus derived from the P337-V70 strain, were sequenced. A comparison of the gp90 gene sequences revealed that amino acid variations among the viruses tested showed as high as 8.2 to 11.5%. In addition, the comparison also indicated that the isolates that recovered from the non-febrile stage were contained in nucleotide insertions in the principal neutralizing domain (PND) region. The insertions were arranged regularly with smaller segments. The nucleotide sequence of the P337-V26 gp90 gene was found to contain a six-nucleotides insertion and seven nucleotide substitutions outside the PND region, when compared with that of the P337-V70 strain. 相似文献
75.
76.
La- and K-doped perovskite-type ceramics, (Sr0.6Ba0.4)1−xLaxPbO3 with x = 0.0−0.1 and (Sr0.6Ba0.4)1−xKxPbO3 with x = 0.00−0.15, were prepared to modify thermoelectric properties of semi-metallic Sr0.6Ba0.4PbO3 via the doping of electrons and holes, respectively. The electrical conductivity σ and Seebeck coefficient S for the ceramics were measured at temperatures of 373–1073 K in air. With the La doping, electron carriers were successively doped and the material changed from a semi-metal for the undoped Sr0.6Ba0.4PbO3 to a metal for the (Sr0.6Ba0.4)0.9La0.1PbO3. With the K doping, the thermoelectric properties were essentially unchanged probably due to the carrier compensation effect by the generation of oxygen deficiencies. The thermoelectric power factor S2σ was maximized to a value of 3.1 × 10−4 Wm−1 K−2 at 773 K for the undoped Sr0.6Ba0.4PbO3 ceramic. 相似文献
77.
T Nada F Moriyasu Y Kono Y Suginoshita T Matsumura K Kobayashi T Nakamura T Chiba 《Canadian Metallurgical Quarterly》1997,16(7):485-491
The aim of this study was to assess the ability of perfluoropropane-filled albumin microspheres to visualize tumor blood flow in woodchuck hepatomas. Ten tumors in five woodchucks with hepatomas were imaged before and after intravenous injection (dosages of 0.01 ml/kg to 2.0 ml/kg) of an agent using color Doppler sonography and gray scale ultrasonography. Both enhanced imaging modalities demonstrated blood flow around and within all tumors. Enhanced gray scale ultrasonography demonstrated sonographic "tumor blush" in seven tumors (70%). In conclusion, tumor blood flow in woodchucks was visualized more clearly using the agent on both color Doppler and gray scale ultrasonography. 相似文献
78.
79.
Hiroyuki Kono Hideharu Mori Minoru Terano Hisayuki Nakatani Isa Nishiyama 《应用聚合物科学杂志》2002,83(14):2976-2983
Additive effects of donors on the initial polymerization of 1,5‐hexadiene with the MgCl2‐supported Ziegler catalysts were investigated by using the stopped‐flow method, temperature rising elution fractionation (TREF) analysis, and kinetic study. The cyclopolymerization of 1,5‐hexadiene proceeded within an extremely short period (≤ 0.2 s) and yielded a unique poly(methylene‐1,3‐cyclopentane). cis ring content and cis–cis unit in meso dyad of the resulting polymer were increased by the addition of electron donors. The influence of internal and external donors was examined by the estimation of kinetic parameters and TREF analysis. Because the addition of the internal donor caused an obvious change in one of the kinetic parameters and the microstructure, an isospecific active site was considered to be formed by the addition of the internal donor. In the case of the external donor, the additive effects on the stereospecificity were weaker than those of the internal donor. It was expected from TREF measurements that the external donor modified an aspecific active site into a lower isospecific active site. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2976–2983, 2002; DOI 10.1002/app.2326 相似文献
80.
David Person Patrick E. Cassidy John W. Fitch Keiji Kono Mitsuru Ueda 《Reactive and Functional Polymers》1996,30(1-3):229-234
Poly(arylene ether)s (9) containing pendant benzoyl groups were prepared by the aromatic substitution reaction of 2,5-difluoro-4-benzoylbenzophenone (7) with bisphenol (8) in the presence of potassium carbonate in N,N-dimethylacetamide. The polycondensation proceeded smoothly at 170°C and produced the desired poly(arylene ether)s with inherent viscosities up to 0.79 dl/g. The polymers were quite soluble in common organic solvents and can be processed into uniform films from solutions. The thermogravimetry of the polymers showed excellent thermal stability, 10% weight losses above 450°C in nitrogen atmosphere. The glass-transition temperatures of the polymers were 138–158°C. 相似文献