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排序方式: 共有542条查询结果,搜索用时 15 毫秒
101.
102.
Masanori Hara Kaori YudouEmiko Kinoshita Kayoko OkazakiKazuyoshi Ichinose Kuniaki WatanabeMasao Matsuyama 《International Journal of Hydrogen Energy》2011,36(19):12333-12337
To study the alloying effects on ZrMn2-H system, thermodynamic properties of Zr(Mn1−xCox)2 hydride were measured by volumetric method. ZrMn2 gave a single plateau region in the pressure-composition isotherm. On the other hand, double plateaus were clearly observed in Zr(Mn0.7Co0.3)2 and Zr(Mn0.6Co0.4)2-H systems. The appearance of the double plateau characteristics would be explained in view of the hydrogen binding in the tetrahedral occupation sites in Zr(Mn1−xCox)2. Since the hydrogen binding in the tetrahedral 2ZrMnCo site would be less stable than that in the 2Zr2Mn site, the equilibrium pressure increases with increasing cobalt content. The appearance of the first plateau was ascribed the increase in the bonding of Mn-H in 2Zr2Mn site adjoining the 2ZrMnCo site. 相似文献
103.
Gennadiy A. Medvedkin Takao Nishi Yuji Katsumata Hideto Miyake Katsuaki Sato 《Solar Energy Materials & Solar Cells》2003,75(1-2):135-143
Point defects in CuGaSe2 single crystals as vacancies VSe, VCu and defect pair (2VCu−+GaCu2+) have been studied by means of electron paramagnetic resonance (EPR) and low-temperature photoluminescence (PL). EPR hyperfine structure has been found at temperatures as low as 1.45–45 K and the temperature dependence of EPR line is discussed. Photo-EPR spectrum reveals optically active behavior of intrinsic point defects in CuGaSe2 crystals. Three bands of PL emission show different origins and two low-energy bands at 1.55 and 1.58 eV have been found to be steady despite H2-, O2- and Se2-annealings. The experimental data added with electric characterization in accordance with the used annealings and together with a defect physics model allow consideration of the point defect ensemble in CuGaSe2 in more detail. 相似文献
104.
Mammalian ADP-ribosylation is poorly understood. An ADP-ribosylprotein hydrolase that acted on ADP-ribosylated actin was purified from rat brain. The molecular weight of this enzyme was 62, 000 as determined by SDS-polyacrylamide gel electrophoresis and gel filtration. Enzyme activity with ADP-ribosylated actin as a substrate was inhibited by NAD, ATP, ADP, and ADP-ribose, but not by AMP. Mg2+ increased Vmax. Purified ADP-ribosylactin hydrolase catalyzed the hydrolysis of ADP-ribosylated subunits Gsalpha, Gialpha, and Goalpha and elongation factor-2. After de-ADP-ribosylation by the purified ADP-ribosylactin hydrolase, the proteins were re-ADP-ribosylated by brain mono-ADP-ribosyltransferases and bacterial toxins. The actin that was de-modified by ADP-ribosylactin hydrolase could form actin filaments. Two kinds of monoclonal antibodies against ADP-ribosylactin hydrolase were prepared and characterized. In an immunohistochemical study, the plasma membranes and cytoplasmic regions of the nerve cells in the rat brain were immunoreactive. In subcellular fractionation of the brains, most of the ADP-ribosylactin hydrolase activity was found in the cytosol and synaptosome fractions. When the synaptosomes were treated with a hypotonic solution, ADP-ribosylactin hydrolase activity was found in the supernatant. Our findings suggest that brain ADP-ribosylactin hydrolase has the important function of polymerizing actin for signal transduction in the cytosol of nerve cells and synaptosomes. 相似文献
105.
Y Hayashi K Matsuyama K Takagi H Sugiura K Yoshikawa 《Canadian Metallurgical Quarterly》1995,213(1):317-324
Necdin is a 325 amino acid residue protein localized to the nuclei of postmitotic neurons, which withdraw permanently from the cell cycle. To examine whether necdin confers the postmitotic phenotype, necdin cDNA was stably transfected into NIH3T3 cells, in which the protein was conditionally expressed using a eukaryotic lac repressor-operator expression system. When the transfectants were induced to express ectopic necdin, cell growth was arrested without appreciable reduction in cell viability. The expressed necdin molecule was localized to the nuclei of the transfectants. These results suggest that necdin is a nuclear factor that governs the permanent arrest of cell growth of postmitotic neurons during development of the nervous systems of vertebrates. 相似文献
106.
107.
Nuchal vascular hamartoma was found in a newborn premature infant who presented with nonimmune hydrops fetalis, pulmonary hypoplasia due to bilateral pleural effusion and polyhydramnios in utero. The baby died 26 hours after birth despite maximal respiratory and circulatory support. Postmortem examination revealed a vascular hamartoma localized to the left posterolateral region of the neck. We suggest that nuchal vascular hamartoma may be associated with fetal hydrops, probably due to compromised lymph drainage. 相似文献
108.
The detailed techniques for improving the efficiency of a fault-diagnosis algorithm can be based on the signed directed graph. This graph represents the structure of the system, and the pattern on the graph represents a state of the system. The usefulness of the improved algorithm is demonstrated using a model of a chemical process comprising a reactor, a heat exchanger and a distillation tower. 相似文献
109.
110.
Seawater desalination by the reverse osmosis (RO) method is an energy-saving system compared with the evaporating method, and can perform seawater desalination efficiently. Seawater RO desalination technology has been established and become a reliable system. Seawater desalination plants using RO technology have spread and the scale of the plants has increased significantly. More economical and efficient RO method seawater desalination systems have come to be required. A high recovery system, which offers reduction of plant construction cost and running cost was devised. Towards realization of this high recovery system, simulation and the field tests were done to confirm the practicality. Furthermore, a high recovery system was adopted for the biggest desalination plant in Japan, and it is performing favorably. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献