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1.
叙述了天铁动力厂4#空分系统辅助油泵应用EV2000变频器控制系统的过程,对运行中出现的溢油、油压波动不稳等故障现象原因进行了分析,提出了改进方案.改进后消除了故障现象,实现了闭环控制油泵的转速和启停,减小了对电机和电网的冲击和振动,提高了设备的可靠性,延长了电机使用寿命,保障了生产的顺利进行.  相似文献   

2.
论述了压铸镁合金的发展现状,介绍了部分压铸镁合金的化学成分及使用特性,分析了其工艺特点.描述了压铸镁合金在汽车工业和电子信息产业中的应用情况,并对今后的发展提出了看法.  相似文献   

3.
高济华 《冶金动力》2013,(11):71-74
用友资产管理系统根据天铁集团的设备管理要求配置了相关的功能模块,实现了设备管理的精细化、科学化、信息化,提高了设备的管理水平,降低了设备维修费用,同时实现了与财务一体化的无缝对接,为相关的钢铁企业设备管理信息化工作提供了参考。  相似文献   

4.
介绍了Access数据库的特点和优点,在采购管理中应用的意义.使用Access编写了<供应仓储管理系统>,论述了该系统的设计思想、程序结构及应用效果.该系统的应用,减轻了工作人员劳动强度、提高了工作效率、确保了物资及时供应、减少了资金的占压.  相似文献   

5.
5052 H32板材生产工艺研究   总被引:2,自引:0,他引:2  
对5052 H32板材的生产工艺进行了试验研究。通过近一年多的技术攻关,优化了熔铸工艺参数,解决了热轧坯料的粘铝和板形问题,优化了冷轧工艺方案和退火制度.从而提高了5052 H32板材的机械性能、深冲折弯性能及表面质量,满足了用户要求。  相似文献   

6.
《有色设备》2013,(6):7-7
2013年12月3日,广西壮族自治区工业和信息化委员会在南宁市组织专家召开了“广西有色金属研发中心创新能力建设项目”验收会。与会专家听取了研发中心建设的工作汇报,审查了有关资料,查看了现场,项目完成了设定的建设目标,提升了研发中心技术创新能力,一致同意项目通过验收。  相似文献   

7.
介绍了国内外海绵钛的生产状况,着重介绍了几种钛的深加工处理方法(钛的冶炼、微弧氧化、氮化及镀铁处理),阐述了钛的应用领域并展望了钛的发展前景.  相似文献   

8.
介绍了邯钢冷轧废水站的配套项目废水处理站的自动控制系统,主要从自控设备组成、网络控制系统等方面论述了控制功能的实现,该系统的应用为ERP的数据采集提供了很好的保证,提高了电气控制的集成度和可靠性,简化了控制环节,提高了生产效率.  相似文献   

9.
介绍了HTB-ZK型耐酸陶瓷泵密封系统结构及运行状况,叙述了静、动力密封系统造成的故障原因,提出了新的结构设计方案,并就改进前后运转情况进行了对比,从而进一步证实了改进方案的可行性、经济性.  相似文献   

10.
介绍了由于5#制氧机空冷塔中部液位异常波动导致整个空气预冷系统波动以及影响了整个空分系统工况不稳定的情况。分析和排查了引起液位波动的原因,综述了空气预冷系统的原理和流程,总结了此次故障教训,为今后的生产起到了警示的作用。累积了一定的经验,同时可以举一反三,对行业有一定的借鉴作用。  相似文献   

11.
The results of hemoglobin determination in the CSF by the method of fluorescence microscopy in 195 patients speaks in favor of relative diagnostical importance of hemoglobin in the supra fall-out CSF for establishing the character of the stroke. The following circumstances testify to this fact: 1) in an artificial admixture of blood in the CSF in some cases there may be hemolysis of "passing" erythrocytes; 2) in a genuine admixture of blood, tests of hemoglobin in the centrifugate of the CSF may be negative since in some cases the transition of hemoglobin into bilirubin in the subarachmoid space occurs more rapidly than the hemolysis of erythrocytes. Thus, the hemoglobin does not accumulate in the liquid in quantities, sufficient enough to be measured by the existing methods; 3) in a large amount of artificial blood admixture, even without a hemolysis of "passing" erythrocytes the hemoglobin tests in the centrifugate of the CSF may be positive at the expense of hemoglobin of the blood plasma.  相似文献   

12.
Transplasma membrane redox plays a significant role in cellular activation and growth. Six isoenzymes could be prepared from purified rat brain synaptic plasma membrane. Polyclonal antibodies have been prepared against six transplasma membrane oxydoreductases (PMO-I to PMO-VI) and the tissue distribution of the various iso-enzymes have been investigated in adult rat brains by means of immunohistochemistry. PMO-I is densely observed in layers I, IV and V of the parietal cortex, in CA1 of the hippocampus (except for the molecular layer), in the caudate putamen, in the dorsal, granular and ventral parts of the auditory nuclei, in some loci of the vestibular nuclei as well as in the deep cerebellar nucleus and in the granular layer of the cerebellar cortex. PMO-II is mainly located in the polymorphic layer of the dentate gyrus and in the deep cerebellar nucleus and in the granular layer of the cerebellar cortex. PMO-III is abundant in the piriform cortex, in the pyramidal layers of both CA1 and CA2, in the diagonal band of the basal ganglia, in the supraoptic nucleus and in various loci of the magnetocellular paraventricular nucleus of the hippothalamus as well as in the vestibular nuclei from the brain stem. In addition PMO-III is also densely present in motor nuclei (oculomotor, facial, hypoglossal and ambiguus nuclei), in the reticular formation and in the deep cerebellar nucleus as well as in the Purkinje layer of the cerebellar cortex. PMO-IV has a similar location but is less abundant in the vestibular nuclei of the sensory brain stem and in the motor nucleus. PMO-V in contrast is poorly present in most brain areas compared to the other iso-enzymes, apart of the Purkinje layer of the cerebellar cortex. Finally PMO-VI is mainly present in the oriens layer and in the stratum radiatum of the hippocampus formation, in the supraoptic and lateral magnocellular nucleus of the hypothalamus, in the mesencephalic trigeminal nucleus, in the ventral auditory nucleus and in the facial nucleus of the brain stem as well as in red nucleus of the reticular formation and in the Purkinje layer of the cerebellar cortex. These data show that the iso-enzymes are located in specific brain nuclei. The significance of the results in respect to the yet very poorly defined function of PMO's is discussed.  相似文献   

13.
Theoretical models featuring cognitive processes have played a fundamental role in advancing knowledge of psychopathology and its treatment and have emphasized the importance of cognition in psychotherapy. Recognition of the importance of cognition in psychotherapy has led to a number of questions that are addressed by the articles in this special section of the Journal of Consulting and Clinical Psychology. Cognitive therapy is well represented in the articles in this special section, but therapeutic procedures that do not represent typical cognitive therapy are also examined. The articles in this special section focus on homework in the modification of cognition, cognition in the treatment of anxiety in adults and in children, change in depressive cognitions in children, cognition and rapid change in the treatment of depression, and the role of cognition in the treatment and prevention of depression that is recurrent. Examination of these types of questions holds the possibility of advances in existing treatments and the possibility of innovations in new treatments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

14.
The presence of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) activities was determined in milk and serum of cows with naturally occurring coliform mastitis (CFM). TNF-alpha was detected in the sera from 26 of 32 cows with CFM. TNF-alpha levels were higher in the sera than in the milk. IL-6 was high in the sera of surviving CFM animals, but was low in animals that died and in healthy controls. Furthermore, the mean level of IL-6 was 20-fold higher in the milk than in the sera of mastitic cows. The level of IL-6 in the serum was correlated to that in the milk in individual animals. The presence of IL-6 and TNF-alpha in the sera appears to relate to severe clinical condition of CFM, in the milk whereas they may play a role in generating inflammation of the mammary gland.  相似文献   

15.
There is an early period of puberty in boys at the age of 10 to 13, accompanied by an increase in the level of follicle stimulating hormone and a low secretion of luteinizing hormone and testosterone, with no secondary sexual signs. The beginning of an increase in the luteinizing hormone and testosterone concentration in boys coincides with the development of secondary sexual signs. The stabilization of the level of luteinizing hormone takes place in boys already at the 2nd degree of the sexual development. The secretion of luteinizing hormone at this point corresponds already to the normal level in adult men. The level of testosterone in the blood continues to increase and does not reach its definitive level until after the age of 17, or at the 5th degree of sexual development. Like in boys, the increase of the follicle stimulating hormone in girls precedes the increase of the luteinizing hormone secretion. The beginning of the increase in the follicle stimulating hormone coincides with an increase in the level of estrogens and testosterone in the blood, and with the appearance of secondary signs of sexual maturation. The increase of the luteinizing hormone secretion takes place later in girls than in boys and is accompanied by a new and significant increase in the level of estrogens in the blood. At the 2nd degree of sexual development, the level of testosterone in the blood of girls is substantially higher than at the other stages.  相似文献   

16.
This study compared the effects of undiluted and 8% ethanol administered orally on gastrointestinal antioxidant components of male and female rats. Eight percent ethanol increased the activities of duodenal glutathione peroxide (29% in males, 14% in females) and superoxide dismutase in female gastric (24%) and male duodenal (15%) mucosa. This dose of ethanol also increased the glutathione content of gastric mucosa (12% in males, 13% in females). Undiluted ethanol decreased glutathione levels in gastric mucosa (22% in males, 11% in females) and increased glutathione peroxide activity in gastric mucosa (14% in males, 9% in females). Undiluted alcohol also produced decreases in the activity of glutathione reductase in stomach (14% in males, 9% in females) and duodenum (16% in males, 12% in females). Undiluted ethanol caused mucosal damage in the body of the stomach in both genders, accompanied by an increase in luminal pH and fluid accumulation in the stomach; these changes were absent in rats given 8% ethanol. The increase in gastrointestinal antioxidant capacity associated with the administration of 8% ethanol may be a factor in the reported cytoprotective effect of lower doses of ethanol.  相似文献   

17.
Concentrations of mercury, cadmium, and other heavy metals in tissues of belugas (Delphinapterus leucas), narwhal (Monodon monoceros) and ringed seals (Phoca hispida) from across the Canadian Arctic are reported. Published and new information is used to provide an overview of metals in tissues of these animals, to delineate the existence of a spatial trend of mercury and cadmium in belugas and ringed seals, and to show a temporal trend is superimposed on the geochemical trend. Mercury concentrations in tissues of Arctic whales and ringed seals were high relative to the Canadian guideline of 0.5 micrograms/g wet wt., for mercury in fish, except in the skin of belugas (0.59-0.78 micrograms/g wet wt.) and flesh of ringed seals (0.39-0.41 micrograms/g wet wt.). In the flesh of belugas (0.94-1.34 micrograms/g wet wt.), and in the liver of ringed seals, tissues that are also consumed by Native people in the Arctic (8.34-27.5 micrograms/g wet wt.), the guideline value was significantly exceeded. Mean lead concentrations in tissues of belugas, narwhal and ringed seals were generally low (0.002-0.028 micrograms/g wet wt.), except in tissues of belugas in the St. Lawrence River (0.10-0.15 micrograms/g wet wt.). The concentration of zinc in the skin of whales was two to three times higher than in other tissues. The concentration of cadmium in organs was highest in narwhal. There was a positive correlation between mercury and selenium in the liver of all three species. The concentration of mercury in tissues of belugas and ringed seals was higher in the western than the eastern Arctic. This was attributed to different natural background concentrations in the western and eastern Arctic of Canada dictated by different geological formations in the two regions. Cadmium concentrations in tissues of belugas and ringed seals were higher in the eastern than the western Arctic. Zinc and copper in some tissues of belugas and ringed seals were also higher in the eastern than the western Arctic. Mercury in the liver of belugas was found to have increased in the western and eastern Arctic over 10-12 years. Mercury in the liver of ringed seals in the western Arctic and narwhal in the eastern Arctic showed similar increases. In recently collected belugas, the rate of accumulation of mercury in the liver was approximately twice that in belugas collected 10-12 years ago. In ringed seals, the rate was three times higher in recent samples compared to 15-20 years ago. There was no temporal change in cadmium levels in tissues of belugas, ringed seals or narwhal.  相似文献   

18.
Using light and electron microscopic morphometric techniques, the effects of 48 hr of extrahepatic biliary obstruction on hepatocyte structure were examined in the rat. Liver cells near the portal area were compared to those in the centrilobular regions of the hepatic lobule. Observations on the normal animals confirm earlier evidence of quantitative differences in the surface density of organelles in hepatocytes located within different regions of the lobule. A striking difference in the quantity of the Golgi complex in the two areas of the lobule was noted for the first time, with the portal cells containing a significantly greater quantity of this organelle than centrolobular hepatocytes. After 48 hr of total obstruction, most of the previously reported qualitative changes in the canalicular and pericanalicular regions were confirmed. Morphometric analysis at the light-microscopic level showed an increase in the number of cells and a decrease in cell size in those cells near the portal area were compared to those in the centrolobular regions of the helar level demonstrated a significant decrease in both rough and smooth surfaced endoplasmic reticulum in cells of both zones, a finding in marked contrast to the hypertrophy of smooth endoplasmic reticulum suggested by other investigators on the basis of qualitative assessments. There was also a striking decrease in the amount of the Golgi complex, limited to cells in the portal regions. In addition, in all zones a decrease in the volume density of mitochondria and lysosomes was noted, whereas the volume of microbodies was increased. It is suggested that this loss in total membrane material within the cell may be secondary to the degranulation and decrease in total surface area of rough surfaced endoplasmic reticulum, an organelle thought to be responsible in part for the synthesis of new cellular membranes. These observations suggest that present concepts concerning the pathogenesis of cholestatic liver disease require reappraisal.  相似文献   

19.
20.
We investigated the in vitro activity and the in vivo efficacy of the beta-lactam-beta-lactamase inhibitor combination cefoperazone-sulbactam against an isogenic series of Klebsiella pneumoniae strains. Both cefoperazone and cefoperazone-sulbactam were active in vitro against a susceptible clinical strain, and the combination was highly effective in the treatment of rat intra-abdominal abscesses. Loss of expression of a 39-kDa outer membrane protein resulted in at least a fourfold increase in the MICs of cefoperazone and cefoperazone-sulbactam but did not appreciably affect the in vivo efficacy of either regimen. Introduction of plasmid RP4, which encodes the TEM-2 beta-lactamase, into the susceptible strain resulted in the loss of in vitro activity and in vivo efficacy for cefoperazone. The in vitro activity of cefoperazone-sulbactam against this strain was diminished, but the antibiotic combination remained highly active in vivo. Introduction of RP4 into the strain lacking the 39-kDa outer membrane protein resulted in a fourfold increase in the in vitro MIC of cefoperazone-sulbactam in comparison with the beta-lactamase-producing susceptible strain and resulted in a loss of in vivo efficacy against infections caused by this strain. These results suggest that the combination of different resistance mechanisms, neither of which alone results in substantially diminished cefoperazone-sulbactam efficacy in vivo, can cause in vivo resistance to the beta-lactam-beta-lactamase inhibitor combination in K. pneumoniae.  相似文献   

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