首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   7篇
  免费   0篇
轻工业   2篇
一般工业技术   2篇
冶金工业   3篇
  2010年   1篇
  2002年   1篇
  1998年   1篇
  1997年   2篇
  1983年   1篇
  1978年   1篇
排序方式: 共有7条查询结果,搜索用时 15 毫秒
1
1.
2.
The equilibrium selenium vapour pressure of VxSe2 (1.2 < x < 1.7) was measured by a thermobalance method at 1053, 1113 and 1163K under controlled selenium vapour pressure. The thermodynamic partial molar quantities of the V3Se4 phase were evaluated from the measured PSe- X isotherms. Further, the powder X-ray and high temperature DTA measurements of the quenched specimens were carried out in order to identify the phase.  相似文献   
3.
The lattice constants of nonstoichiometric CdI2-type transition-metal dichalcogenides exhibit a characteristic feature. One of the body-diagonal lengths of the hexagonal lattice is kept nearly constant over the homogeneity range. This body-diagonal direction involves the full-layer metal-chalcogen bonds. The heats of formation of various CdI2-type transition-metal dichalcogenides are correlated to the reduced length which is derived from that body-diagonal and the ideal ionic radii. The ΔHof values of the CdI2-type transition-metal dichalcogenides can be estimated from the following empilical formula within the error of about 10kcal/mole. ΔHof = 1030 LR ? 144 (kcal/mole). LR: Reduced length.  相似文献   
4.
To verify the optimal hematocrit (Hct) level in the treatment of cerebral ischemia, cerebral oxygen transport (CTO2) and cerebral oxygen metabolism (CMRO2) in graded isovolemic hemodilution were evaluated during cerebral ischemia. Isovolemic hemodilution with low molecular weight dextran to stepwise lower Hct from 43% to 36%, 31%, and 26% was carried out in 13 splenectomized dogs, 6 h after global cerebral ischemia. Global ischemia of the animals was produced by multiple intra- and extracranial ligations of cerebral arteries. Cerebral blood flow (CBF) was measured with radioisotope labeled microspheres. CTO2, CMRO2, and oxygen extraction fraction (OEF) were calculated from CBF, arterial oxygen content (CaO2), and venous oxygen content (CvO2). In dogs with global cerebral ischemia, CBF increased with graded isovolemic hemodilution (r=-0.73, P<0.05). CTO2 reached its highest value at a Hct level of 31.3%. CTO2 at Hct of 36.1% and 31.3% was statistically different from the value measured at a Hct of 43.3%, and there was a decrease when Hct was lowered to 25.9%. CMRO2 was the highest when Hct was at 31.3% and differed significantly from the value measured at a Hct of 43.3%. There was a 10% increase of OEF when Hct was at 25.9%; however this change was not statistically significant compared with the OEF at Hct of 36.1% and 31.3%, respectively. These findings indicate that CTO2 and CMRO2 were the highest when Hct was reduced to 31% in hemodilution. Hct at 31% is the optimum for cerebral metabolism in ischemic status. Uncoupling of CTO2, CMRO2 with CaO2 was also observed in this study. This phenomenon suggests that hemodilution to augment cerebral circulation may be at least partially attributed to the beneficial effects of hemorheologic improvement in the microcirculation of the ischemic brain.  相似文献   
5.
To investigate cortical activities related to the visual recognition of characters, we recorded the magnetoencephalography (MEG) in six normal subjects who were encouraged to discriminate capital English letters displayed for a brief period. To reduce the primary responses evoked by the luminance change in the striate cortex (V1), we used a novel stimulus method, random dots blinking (RDB), by means of the temporal changes of patterns using a large number of small random dots. Along with the MEG recording, we also measured the discrimination accuracy rate (%) to know how well the subjects recognized the letters. One clear component, about 300 ms in peak latency, was identified in all six subjects. Its peak amplitude and the discrimination accuracy rate increased similarly as the character display duration became longer. Its signal source was estimated in the extrastriate cortex, around the fusiform gyrus, in the right hemisphere. We suspect that the activity in these cortical areas has strong relation to the conscious perception of characters.  相似文献   
6.
RATIONALE AND OBJECTIVES: The author introduces a number of techniques well known in exploratory pattern recognition that can be used for the analysis of the shape of metacarpophalangeal profiles. It is shown that the classic Q-scores must be adapted for such techniques to be applicable. METHODS: A new set of scores (P-scores) describing the shape of metacarpophalangeal profiles is derived. The application of various pattern-recognition techniques that use P-scores is described, using a collection of metacarpophalangeal length measurements in patients with various pathologic conditions. RESULTS: Different pattern-recognition techniques highlight different aspects of the profiles, which, when interpreted together, yield a consistent understanding of the data set and insight in individual patients' peculiarities. CONCLUSIONS: The use of scale-invariant scores is imperative when the shape of profiles is to be analyzed, especially in data sets with large variations in the scale factor. Methods of pattern recognition using such scores are of potential clinical interest.  相似文献   
7.
The bacteriocins produced by Lactococcus lactis subsp. lactis C101910 (C101910) and NBRC 12007 (NBRC 12007) were used to prevent the growth of sake spoiling hiochi bacteria (Lactobacillus hilgardii, Lactobacillus fructivorans, and Lactobacillus paracasei) in namazake, which is raw (unpasteurized) sake. The bacteriocin concentrations required for decreasing the viable cell concentrations of L. hilgardii and L. fructivorans below the detection limit (1.0 × 102 cells/ml) in 24 h from the initial concentration of 4.0–9.5 × 105 cells/ml in the namazake at pH 4.5 and at 4°C, were 18–35 U/ml and 5.6 U/ml for the bacteriocin from C101910 and NBRC 12007, respectively. To decrease the viable cell concentration of L. paracasei from the initial concentration of 7.5 × 105 cells/ml to below the detection limit (1.0 × 102 cells/ml) in 24 h, 350 U/ml bacteriocin from C101910 and 140 U/ml bacteriocin from NBRC 12007 were required. In experiments using McIlvaine buffer (pH 4.5) with 15% ethanol instead of namazake as the medium, the viable cell concentrations of L. hilgardii and L. paracasei decreased to less than 1.0 × 102 cells/ml, whereas those of L. fructivorans decreased to less than 1.0 × 103 cells/ml, when bacteriocins were added at the concentrations that had proven effective in namazake. The membrane depolarization assay using a fluorescent probe showed that the presence of ethanol stimulated the collapse of the membrane potential induced by bacteriocins. The ethanol induced collapse of the membrane potential suggests that the application of bacteriocins at the storage stage of namazake is more beneficial than when used in other stages of the sake brewing process.  相似文献   
1
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号