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排序方式: 共有310条查询结果,搜索用时 15 毫秒
1.
三级配混凝土输送泵在鱼塘水电站混凝土施工中的应用 总被引:1,自引:0,他引:1
鱼塘水电站溢洪道混凝土共计14.9万m3,由于受不良地质和洪水冲毁围堰等因素影响致使开挖结束时工期严重滞后,而整个电站安全度汛又迫在眉睫,故必须寻求加快溢洪道混凝土浇筑速度的办法。为此,采用国内首批HBT120A三级配混凝土输送泵作为混凝土主要的入仓手段,使施工进度明显加快,弥补了原已滞后的工期,保证了鱼塘水电站溢洪道工程安全度汛目标的实现,并为2005年9月底水库下闸蓄水目标的实现奠定了坚实的基础。本文主要介绍HBT120A三级配混凝土输送泵在该工程施工中的应用。 相似文献
2.
Visual and auditory stimulus discrimination tasks, analogous to those used in the Reitan-Klove Sensory Perceptual Examination, were performed by 12 cocaine-dependent and 5 alcohol-dependent patients after 1 week, 3 weeks, and 3 months of verified abstinence. Sixteen control subjects, who were not substance-dependent, performed the same tasks after comparable intervals. During each task, either visual or auditory stimuli were presented in the left, in the right, or in both sensory fields. A simple key press was made to discriminate these conditions. Cocaine-dependent patients responded more slowly than control subjects during both tasks. The reaction-time slowing persisted across all three sessions, spanning a 3-month period of abstinence. There were no significant differences between the cocaine-dependent and control groups in response accuracy. In the context of other findings, these findings are interpreted as reflecting an enduring effect of prior cocaine dependence on motor as opposed to sensory functioning. 相似文献
3.
IuA Magakian EM Karalova LO Abroian SA Karapetian 《Canadian Metallurgical Quarterly》1997,39(8):705-710
Cytophotometry of rat blood erythroid cells during anaemia, induced by phenylhydrazin (4-8 days from the beginning of injections), revealed that all forms of bone marrow containing haemoglobin were thrown into the blood. On its peak (4th day), the greatest contribution in blood haemoglobinization (50%) is made by microcytes. From the 5th day and up to the end of the restoration period the important role in this process is played by macrocytes. From the 6th day the role of normocytes increases, whose contribution by 8th day reaches 70% of the whole haemoglobin amount in blood. In contrary to anaemizated birds, whose erythroid cells ripen in blood, in rats all the transformations of erythron during anaemia are accomplished in bone marrow. 相似文献
4.
GR Login M Aoki M Yamakawa LO Lunardi EC Digenis N Tanda LB Schwartz AM Dvorak 《Canadian Metallurgical Quarterly》1997,45(10):1379-1391
The subcellular events responsible for release of mediators by mast cells may help to clarify roles for mast cells in health and disease. In this study we show that the granule-associated protease chymase is also within cytoplasmic vesicles in appropriately stimulated rat peritoneal mast cells. Rat peritoneal mast cells were recovered before or 1-10 sec after exposure to the secretogogue compound 48/80 (10 micrograms/ml) and then were examined by radioimmunoassay to quantify histamine release or were processed, using routine methods for postembedding immunoelectron microscopy, to identify the subcellular localization of chymase. In comparison to unstimulated cells, compound 48/80 stimulated cells in two independent experiments showed an increase (15%, 28%) in the surface area of the cell and a decrease (12%, 6%) in the surface area of the total granule compartment before degranulation channel formation. These global cellular changes occurred in a background of transient but significant (p < 0.01) increases in the area and number of chymase-immunoreactive vesicles per microns2 cytoplasm. These changes were detectable at 5 or 7 sec after stimulation with compound 48/80 but returned to near prestimulation levels by 9 or 10 sec after addition of compound 48/80 (total cumulative histamine release was 28% by 8 sec and 47% by 14 sec). These observations suggest that vesicles participate in the early stages of regulated secretion of chymase from rat peritoneal mast cells. 相似文献
5.
Electron microscopic investigation of the rabbit [correction of rat] thoracic aorta revealed endothelium to be most vulnerable to the damage in experimental hypercholesterolemia. Administration of precursor of nitric oxide L-arginine against the background of hypercholesterolemia resulted in activation of functional activity of the endothelium of aorta. This notion is supported by an increase of the quantity of protein-synthesizing structures (ribosomes, polysomes, canaliculi of endoplasmic network), secretory granules vs rabbits on atherogenic diet. At stimulation of NO-synthase activity of endothelium the dilatory reactions of aortal strips to acetylcholine are improved. 相似文献
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7.
PURPOSE: To develop and evaluate a simple, yet well defined, method to measure diffusion in semi-solids, i.e. polymeric materials. METHODS: The method was based on a concept where equivalent discs of polymeric films were cut and stacked on top of each other. The diffusion process was allowed to proceed unidimensionally through the stack of films perpendicular to the film surface. After an appropriate time, the stack was analysed disc by disc with respect to solute content and from the concentration profile so obtained the diffusion coefficient was calculated. RESULTS: An all-in-one device was developed, manufactured in stainless-steel, that cuts circular discs and stores each one successively in a "stack" in the cell compartment. CONCLUSIONS: Data from a silicone based system shows that the method, although simple, is accurate and reproducible. 相似文献
8.
光催化技术因其高效、绿色的优点,成为解决环境问题和能源危机的有效技术。研制性能优良的光催化剂是应用和发展光催化技术的研究核心之一。Bi系半导体光催化剂因其在可见光下具有良好的光催化性能而引起人们广泛的关注。为此,分类列举了几种常见的铋系光催化剂及其制备,综述了在光能利用率等方面通过掺杂改性取得的重大成果,并简要介绍了含高价铋的光催化剂的制备及其光催化性能。通过类比分析,从基础理论和实际应用方面提出了相关问题和展望。 相似文献
9.
高层建筑火灾安全模糊评价 总被引:9,自引:0,他引:9
将模糊数学中的综合评判模型与高层建筑中对火灾安全有影响的因子相结合,建立了高层建筑火灾安全评价的模糊综合评判模型.在该模型中对数据的处理、权重的选取、多层次的综合评判进行了方法上的研究.对某高层建筑火灾安全评价中的评价指标与等级的选取、评价指标标准的确定、权重的确定等进行了实例分析,给出了评价结果并对结果进行了分析. 相似文献
10.