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51.
介绍了老屋基矿采、掘工作面防突措施情况,总结了老屋基矿防治煤与瓦斯突出措施取得的效果。  相似文献   
52.
以红岩6-250ZCD柴油机故障为例,发现并分析了柴油机排气呈白色的特殊原因,有利于今后故障的快速确诊.  相似文献   
53.
Autophagic degradation of cytoplasm (including protein, RNA etc.) is a non-selective bulk process, as indicated by ultrastructural evidence and by the similarity in autophagic sequestration rates of various cytosolic enzymes with different half-lives. The initial autophagic sequestration step, performed by a poorly-characterized organelle called a phagophore, is subject tofeedback inhibition by purines and amino acids, the effect of the latter being potentiated by insulin and antagonized by glucagon. Epinephrine and other adrenergic agonists inhibit autophagic sequestration through a prazosin-sensitive 1-adrenergic mechanism. The sequestration is also inhibited by cAMP and by protein phosphorylation as indicated by the effects of cyclic nucleotide analogues, phosphodiesterase inhibitors and okadaic acid.Asparagine specifically inhibits autophagic-lysosomal fusion without having any significant effects on autophagic sequestration, on intralysosomal degradation or on the endocytic pathway. Autophaged material that accumulates in prelysosomal vacuoles in the presence of asparagine is accessible to endocytosed enzymes, revealing the existence of an amphifunctional organelle, the amphisome. Evidence from several cell types suggests that endocytosis may be coupled to autophagy to a variable extent, and that the amphisome may play a central role as a collecting station for material destined for lysosomal degradation.Protein degradation can also take place in a salvage compartment closely associated with the endoplasmic reticulum (ER). In this compartment unassembled protein chains are degraded by uncharacterized proteinases, while resident proteins roturn to the ER and assembled secretory and membrane proteins proceed through the Golgi apparatus. In thetrans-Golgi network some proteins are proteolytically processed by Ca2+-dependent proteinases; furthermore, this compartment sorts proteins to lysosomes, various membrane domains, endosomes or secretory vesicles/granules. Processing of both endogenous and exogenous proteins can occurr in endosomes, which may play a particularly important role in antigen processing and presentation. Proteins in endosomes or secretory compartments can either be exocytosed, or channeled to lysosomes for degradation. The switch mechanisms which decide between these options are subject to bioregulation by external agents (hormones and growth factors), and may play an important role in the control of protein uptake and secretion.  相似文献   
54.
在一台1.5 L带废气涡轮增压的直喷汽油机上进行了电动增压和废气再循环(exhaust gas recirculation, EGR)协同对发动机动力性和经济性的影响规律试验研究。结果表明:全负荷下电动增压促进最高废气再循环率随转速的上升而下降,在4个试验转速下分别提升了17.7%、15.2%、13.84%和0;部分负荷下电动增压促进最高废气再循环率随负荷的提高与转速下降,在6个试验工况下最高废气再循环率分别被提高了23.63%、30.31%、0、14.09%、19.74%和0。全负荷与较低的3个转速下电动增压介入后有效燃油消耗率(brake specific fuel consumption, BSFC)降低近10%,最高转速下废气涡轮增压完全取代电动增压;部分负荷下的两组工况内,电动增压介入后,最高BSFC降低了10.8%和8.4%。结论表明合理应用电增压促进最高废气再循环率可以提升发动机的燃油经济性并保持较高的动力性。  相似文献   
55.
Chemical structure of immature sulfur-rich kerogen and composition of immature sulfur-rich crude oil in Jianghun oil field have been studied. In molecular level, crude oil differs from thermolysed and chemolysed products of kerogen but does resemble the bitumen in immature sulfur-rich source rock. Therefore, immature sulfur-rich oil may be derived from the expelling of bitumen rather than from thermal cracking of kerogen.  相似文献   
56.
The isotopic cumpositions of helium have been investigated in hot spring gases sampled from the Liaodong Peninsula. China. The3He/4He ratios range from 0.14 Ra (0.14 times the atmospheric3He/4He ratio of 1.40 × 10-6 to 0.72 Ra.3He/4He versus4He/20Ne ratios and He contents suggest that a small amount of mantle-derived helium reaches the earth’s surface. Helium iwtope ratios of the hot spring gases show a distribution pattern similar to the regional heat flow values, indicating that the positive thermal anomaly occurring in the rtrea is closely associated with the presence of mantle-derived helium. The observations described above provide some significant evidence that the molten magma originating from partial melting of the upper mantle may have intruded into the continental crust along the activity fault. The coupling of the presence of mantle He and heat flow anomalies to seismic activity in studied region seem to imply that there is an internal relationship between mantle degassing and seismic activity.  相似文献   
57.
Study of forming mechanism of "chimney-effect" (CE) has important significance for basic theory and applications of non-seismic geophysical and geochemical methods locating oil/gas reservoirs. The theoretical basis of comprehensive evaluation of mechanism of CE using principles of magnetism, geochemistry and mineralogy has been reviewed, with the problems to be solved: (ⅰ) study for the relationship between process of oil/gas migration and geochemical field; (ⅱ) analysis of genesis of magnetic, geochemical and mineralogical anomaly; (ⅲ) interpretation of surface soil magnetism and geochemical anomaly combined with seismic data.  相似文献   
58.
液膜法烟气脱硫试验研究:Ⅱ.促进传递机理与数学模型   总被引:1,自引:0,他引:1  
推导了二氧化硫在纯水和柠檬酸钠溶液中稳态渗透通量表达式,研究了SO2在液膜中的促进传递机理,用局部平衡理论及非平衡边界层理论推导了SO2通过膜液的渗透模型;考虑了溶液粘度、溶液的非理想性及盐效应等物理化学性质和热力学性质等因素对SO2渗透行为的影响,并将实验所得数据与模拟值进行了比较。  相似文献   
59.
影响油气运移的应力场地温场渗流场耦合的双重介质模型   总被引:4,自引:0,他引:4  
地应力场、地温场和渗流场是影响油气运移的主要因素。以此为基础,研究了含油气盆地双重介质体系内流体与岩体相互的力学作用关系,提出了双重介质体系内渗流场、岩体地应力场和地温场耦合的非线性动力学模型。  相似文献   
60.
研究了高频气体放电等离子休对铁电体电滞特性的改性作用,并对其改性机现作了理论分析。研究表明:铁电体PZST经高频气体放电等离子体处理后,其电滞特性有明显改变,其中,矫顽电场强度Ee减小;自发极化强度Ps不变,其物理意义是铁电体电畴反转所需的能量降低;非线性增强。本文为铁电体电滞特性及其电光和光学非线性效应等的改变提供了一种新的物理实验方法。  相似文献   
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