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991.
With the mine exploitation depth getting deeper and deeper, the mine heat-harm turns into another natural disaster after the five disasters, which are the roof, the gas, the fire, the dust and the flood disaster. Compared with other researches on prevention and cure against the heat-harm, the research on prevention and cure against the heat-harm in constructing mine are less. Referring to the experience of prevention and cure against the heat-harm home and 'abroad, analyzing the characteristic of cooling in the constructing mine, and based on the ground former freezing equipments and the modified mine temporary cooling equipments, the paper proposed four technical projects. By comparing with the four technical projects, the second project is preponderant both in technology and economy and can solve the heat-harm of the constructing mine, which is proved by the forecast and calculation. The project can be widely applied in de-temperature tasks of high temperature and heat-harm mines during the mine constructing period and in the exploiting preparing phase.  相似文献   
992.
993.
994.
浅谈混水直供供热方式的运行特征及经济性   总被引:2,自引:0,他引:2  
本文主要是对混水直供供热方式在实际应用中的运行特征进行阐述探讨,混水直供供热方式工艺结构简洁、二次网静压定压方式独特—回水阀门定压、运行稳定经济、供热效果良好,重点对混水直供供热方式的运行特征阐述及相对间接供热方式的经济比较分析。  相似文献   
995.
圆周合成孔径雷达(CSAR)中,由于雷达平台绕观测场景圆周飞行,雷达和地面目标之间的距离方程复杂,目标的距离向参数和方位参数之间有复杂的耦合关系,导致单独估计动目标距离向速度参数的难度加大。提出一种基于子孔径分解的太赫兹CSAR运动目标距离向速度估计方法,选择合适的子孔径角度,对CSAR进行子孔径分解,在子孔径条件下,通过小角度近似,可以实现运动目标距离向速度和其他参数间的解耦合,准确估计运动目标的距离向速度,实现运动目标的精确重定位。仿真和实测数据验证了该算法的有效性。  相似文献   
996.
摩擦改进剂对改善燃油经济性的影响研究   总被引:2,自引:0,他引:2  
李桂云  刘岚  陈刚  金理力  蔡继元 《润滑与密封》2007,32(4):140-141,144
采用四球机试验,考察了钼胺化合物、二烷基二硫代氨基甲酸钼、无灰型摩擦改进剂与摩擦因数的关系以及它们之间的复配作用。结果表明:摩擦改进剂(FM)降低摩擦因数的效果与其化学结构有关;加入量提高,摩擦因数的改善效果明显;不同化学结构的摩擦改进剂复配使用,可以减低整个温度区的摩擦因数。  相似文献   
997.
介绍了新型规整填料Zugrid 64 X和Zupak125 Y在中国石油兰州石化分公司5 Mt/a常减压装置减压塔提馏段的工业应用情况.运行结果表明,新型规整填料具有明显的节能降耗优势,分离效果好,渣油中500 ℃以下的馏分质量分数仅为2.58%,且蒸汽用量较低[m(蒸汽)/m(渣油)为9 kg/t],操作成本低,抗堵塞性能良好.  相似文献   
998.
Gonadotropin-inhibitory hormone (GnIH) is a reproductive inhibitor and an endogenous orexigenic neuropeptide that may be involved in energy homeostasis and reproduction. However, whether GnIH is a molecular signal link of metabolism and the reproductive system, and thus, regulates reproductive activity as a function of the energy state, is still unknown. In the present study, we investigated the involvement of GnIH in glycolipid metabolism and reproduction in vivo, and in the coupling between these two processes in the testis level. Our results showed that chronic intraperitoneal injection of GnIH into male mice not only increased food intake and altered meal microstructure but also significantly elevated body mass due to the increased mass of liver and epididymal white adipose tissue (eWAT), despite the loss of testicular weight. Furthermore, chronic intraperitoneal administration of GnIH to male mice resulted in obesity-related glycolipid metabolic derangements, showing hyperlipidemia, hyperglycemia, glucose intolerance, and insulin resistance through changes in the expression of glucose and lipid metabolism-related genes in the pancreas and eWAT, respectively. Interestingly, the expression of GnIH and GPR147 was markedly increased in the testis of mice under conditions of energy imbalance, such as fasting, acute hypoglycemia, and hyperglycemia. In addition, chronic GnIH injection markedly inhibited glucose and lipid metabolism of mice testis while significantly decreasing testosterone synthesis and sperm quality, inducing hypogonadism. These observations indicated that orexigenic GnIH triggers hyperphagia-induced obesity-related metabolic derangements and hypogonadism in male mice, suggesting that GnIH is an emerging candidate for coupling metabolism and fertility by involvement in obesity and metabolic disorder-induced reproductive dysfunction of the testes.  相似文献   
999.
美国城市公共安全应急体系建设方法研究   总被引:2,自引:0,他引:2  
金磊 《规划师》2008,24(2):81-84
全面紧急事态管理是美国公共安全管理中最基本的原则,包括全危险方法、综合紧急事态管理系统、紧急事态管理的生命周期、对各级政府及组织紧急救援资源的统一调配.美国国土安全部确定了了解、防止、保护、应对、恢复、服务和组织品质七大安全战略目标.美国联邦紧急事务管理局除制订全国防灾计划外,还制订可持续减灾计划和应急反应计划.社区应急反应小组是美国重要的市民组织队伍.  相似文献   
1000.
Mycoplasma hyopneumoniae (Mhp), the primary pathogen causing Mycoplasma pneumonia of swine (MPS), brings massive economic losses worldwide. Genomic variability and post-translational protein modification can enhance the immune evasion of Mhp, which makes MPS prone to recurrent outbreaks on farms, even with vaccination or other treatments. The reverse vaccinology pipeline has been developed as an attractive potential method for vaccine development due to its high efficiency and applicability. In this study, a multi-epitope vaccine for Mhp was developed, and its immune responses were evaluated in mice and piglets. Genomic core proteins of Mhp were retrieved through pan-genome analysis, and four immunodominant antigens were screened by host homologous protein removal, membrane protein screening, and virulence factor identification. One immunodominant antigen, AAV27984.1 (membrane nuclease), was expressed by E. coli and named rMhp597. For epitope prioritization, 35 B-cell-derived epitopes were identified from the four immunodominant antigens, and 10 MHC-I and 6 MHC-II binding epitopes were further identified. The MHC-I/II binding epitopes were merged and combined to produce recombinant proteins MhpMEV and MhpMEVC6His, which were used for animal immunization and structural analysis, respectively. Immunization of mice and piglets demonstrated that MhpMEV could induce humoral and cellular immune responses. The mouse serum antibodies could detect all 11 synthetic epitopes, and the piglet antiserum suppressed the nuclease activity of rMhp597. Moreover, piglet serum antibodies could also detect cultured Mhp strain 168. In summary, this study provides immunoassay results for a multi-epitope vaccine derived from the reverse vaccinology pipeline, and offers an alternative vaccine for MPS.  相似文献   
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