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911.
四川石棉大水沟碲矿床的同位素地质研究 总被引:6,自引:0,他引:6
石棉大水沟相矿是世界首例独立的破多金属矿床。矿体严格产于变质岩中,成矿作用在时间上与赋矿围岩经受的区域动热变质作用相一致。成矿输液的6D值为一68.7%-一41.6%,8'勺值为2·61‰~11.93‰,它最可能来源于变质水,是赋矿围岩在区域动热变质过程中发生的脱挥发反应形成的。Ph,Sr,S,C同位素研究表明,成矿物质具多来源特点,成矿组分是在区域动热变质的有利条件下,通过变质热液对围岩的浸取而它集成矿。 相似文献
912.
Ehrlich carcinoma and EL-4 thymoma ascites cells were subjected in vitro to heat shock, ATP depletion, oxidative stress, Ca2+ overlading and iodoacetamide treatment. After the transient stresses, Triton (X-100)-insoluble TIS) fractions were isolated from the cells and analysed by electrophoresis and immunoblotting. All stresses used caused rapid aggregation of cell proteins. This was manifested in a signficant rise in protein content in the TIS fractions. The protein increase was mostly due to and increase in the insolubility of actin, 57 kDa protein of intermediate filaments, 70 kDa heat shock protein (HSP 70), and some specific proteins whose insolubilization was a characteristic sign for each type of cell injury. Different survival rates in the cell lines after either stress corrlated well with differences in their TIS protein accretion. Possible mechanisms for stress-induced protein aggregation and its relationship with cell viability are suggested. 相似文献
913.
R. J. Capon K. Elsbury M. S. Butler C. C. Lu J. N. A. Hooper J. A. P. Rostas K. J. O'Brien L. -M. Mudge A. T. R. Sim 《Cellular and molecular life sciences : CMLS》1993,49(3):263-264
The Antarctic marine spongeTedania charcoti has been shown to contain extraordinarily high natural concentrations of cadmium and zinc, which have in turn been correlated to the ability of the crude ethanol extract to modulate protein phosphorylation in chicken forebrain and to inhibit the growth of several test bacteria. 相似文献
914.
In order to improve the quality of yarn,a research was carried out at ring spinning.A modifiedtraveller has been used to reduce the yarn hairiness vastly.According to the statistical analysis ofthe data,it was found that the geometrical shape of travellers is the key factor affecting the yarnhairiness at ring spinning. 相似文献
915.
以金霉素产生菌H-502作为出发菌株,采用紫外线加氯化锂作为复合诱变剂,通过生物技术手段获得了F-303变株。投产结果表明,该复株具有孢子萌发率高,发酵周期短,发酵单位高和放罐体积大的特点,发酵指数超过国际先进水平。 相似文献
916.
The differences of thermal conduction and its temperature-varying track of the heat source body at various structural environments have been studied. Hypothetically , geologic heat source body is cut successively into several segregative bodies with a fixed cubage . With the segmented number increasing , the conductive surface area of heat source body begins to get larger, which separately is similar to the heat geologic body in different tectonic zones that
has a various enclosed coefficient . Finite-element simulation result shows that
the thermal conduction speed of spreading from the heat source body to its wall rock is slow→higher→ highest, when heat source bodies are situated respectively at compressive, shear and tensile deformation zones, corresponding rates of their temperature drop are low→ higher→ highest .
Research indicates that the temperature ' s dropping rate of heat source body has an inverse relationship with enclosed coefficient η for different structural zones . This result can explain the tectono-physicochemical reason of magmatite evolution and its. difference . 相似文献
917.
A plant regulator controlling development of symbiotic root nodules 总被引:37,自引:0,他引:37
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