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161.
Vijay P.Singh 《北京师范大学学报(自然科学版)》2010,46(3)
借助Shannon熵和最大熵原理提出了熵理论,并基于此理论,提出了一种水文模拟方法,结合两个实例阐述了该方法在下渗和流速分布模拟中的应用. 相似文献
162.
Bulk material of (Se80Te20)100 xAgx (0rxr4) system was prepared by using a conventional
melt quenching technique. Thin films of a-(Se80Te20)100 xAgx (0rxr4) were deposited by the
vacuum evaporation technique at a base pressure of 10 4 mbar onto well-cleaned glass substrates.
Temperature dependence of electrical conductivity in the temperature range of 263–333 K has been
studied. There is increase in the value of conductivity with increase in temperature as well as with
Ag content. The measurements of intensity dependence of photoconductivity show that the photoconductivity
increases with intensity as a power law where the power is found to be between 0.5 and
1.0, representing the continuous distribution of traps. Rise and decay of photocurrent with time at
room temperature at different light intensities for (Se80Te20)98Ag2 thin film samples have also been
reported. The results have been explained on the basis of the Dember voltage and interaction between
photoexcited holes and the trapped electrons on the surface. 相似文献
163.
A. Shah F. Nagao V. Sahgal H. Singh 《Cellular and molecular life sciences : CMLS》1985,41(11):1396-1398
Summary The gastrocnemius muscle of the rat showed no morphological, histometric or plasma membrane changes, after sciatic nerve stimulation with a 5 mA current for 30 to 60 min, 10 mA for 30 min and 15 mA for 5 min. However, 10 mA for 60 and 200 min gave rise to mitochondrial and plasma membrane abnormalities. These changes were absent after a rest period. The results indicated the sciatic nerve stimulation at 10 mA for 60 and 200 min caused reversible changes in the rat skeletal muscle mitochondria and plasma membrane. 相似文献
164.
C Kaschka-Dierich A Adams T Lindahl G W Bornkamm G Bjursell G Klein B C Giovanella S Singh 《Nature》1976,260(5549):302-306
Tumour biopsies from Burkitt lymphoma patients, as well as human nasopharyngeal carcinoma cells growing in athymic mice, contain Epstein-Barr virus DNA as covalently closed circular DNA. In addition integrated viral DNA sequences seem to be present. 相似文献
165.
Zusammenfassung Der Sitz der Aktivit?t alkalischer und saurer Phosphatase in den Hoden vonMeriones undSuncus war meist identisch, doch wurde beiSuncus auch festgestellt, dass da wo die hintere Kernkappe in verschiedenen Keimzellen auftrat, die Kernmembranen und der Nucleolus
des Zellkerns der Zwischenzellen stark positiv reagierten.
相似文献
166.
Zusammenfassung Eine neue Lösung der Gleichgewichtsgleichung in der (, )-Ebene wurde für eine isotherme Gaskugel gefunden. 相似文献
167.
Summary Silkgland, fatbody, hemolymph and midgut of eri-silkworm present tissue specific turnover in their biochemical correlates in preparation for spinning of the cocoon which is followed by larval-pupal transformation.Acknowledgment. The authors are thankful to Dr R. N. Singh, Principal, for providing the necessary facilities, to Dr A. B. Das, Zoology Dept. Visvabharti University for valuable suggestions and to Indian Council of Agricultural Research, New Delhi, India, for financial assistance. 相似文献
168.
Zusammenfassung Es wird ein Test angewendet, der native und denaturierte DNS unterscheiden lässt. Er besteht auf einer Verklumpung nativer DNS bei Zugabe von kationisierten Stoffen, während denaturierte DNS nur eine Trübung, respektive einen Niederschlag gibt. 相似文献
169.
Automobile companies that spend billions of dollars annually towards warranty cost, give high priority to warranty reduction programs. Forecasting of automobile warranty performance plays an important role towards these efforts. The forecasting process involves prediction of not only the specific months-in-service (MIS) warranty performance at certain future time, but also at future MIS values. However, ‘maturing data‘ (also called warranty growth) phenomena that causes warranty performance at specific MIS values to change with time, makes such a forecasting task challenging. Although warranty forecasting methods such as log-log plots and dynamic linear models appear in literature, there is a need for applications addressing the well recognized issue of ‘maturing data‘. In this paper we use an artificial neural network for the forecasting of warranty performance in presence of ‘maturing data‘ phenomena. The network parameters are optimized by minimizing the training and testing errors using response surface methodology. This application shows the effectiveness of neural networks in the forecasting of automobile warranty performance in the presence of the ‘maturing data‘ phenomena. 相似文献
170.
Intraperitoneal administration of tuftsin-M [Thr-Lys-Pro-Arg-NH-(CH2)2-NH-CO-C15H31] to Balb/C mice has been shown to induce a respiratory burst in the peritoneal exudate cells. The macrophages exhibited enhanced levels of O2-, H2O2, NADPH oxidase and myeloperoxidase, but the activities of superoxide dismutase, catalase and glutathione peroxidase remained virtually unchanged. The magnitude of the oxidative burst depended directly on the dose of tuftsin-M; higher activity was observed at higher doses of the peptide. Tuftsin-M enhanced the generation of both O2- and H2O2 under in vitro conditions, as did phorbol myristate acetate. These results suggest that tuftsin-M could enhance non-specific defence against infections by activating the macrophages. 相似文献