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21.
Abstracts are not published in this journal This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   
22.
Abstracts are not published in this journal This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   
23.
X100试验管线钢管的规范和生产   总被引:1,自引:1,他引:0  
介绍了位于英国诺林伯利亚,钢管直径1 219 mm(48 in),输气压力18 MPa(180 bar),由英国BP公司承建的X100试验管线的建设概况.根据X100试验管线的设计参数制定了相应的钢管规范,设计了X100管线钢管母材、焊缝金属和热影响区的合金成分.按设计的合金成分由住友金属鹿岛钢铁厂生产了钢材、钢板,并...  相似文献   
24.
A study was carried out to see if the potential of renewable energy sources other than hy droelectric power, such as wind, photovoltaic, solar thermal, biomass and waste energy sources, can meet the current energy consumption in Yakushima. The current electricity consumption can be covered by wind and photovoltaic energy sources. The total potential of wind and photovoltaic energy sources is 5.4 times as much as the current electricity consumption. LP gas and kerosene can be replaced by solar thermal and biogas energy. The potential of plant biomass and municipal waste is not sufficient (approximately one third) to cover the rest of the fossil fuels (gasoline, diesel oil and heavy oil). Also, plant biomass and municipal waste must be converted into fluid form. This shortage can be covered by the po tential of wind and photovoltaic energy sources. We also investigated the possibility of tourism expansion using the potential of wind and photovoltaic energy sources. Taking into account three types of capacity (energy, accommodation and transportation), Yakushima can accept approximately four times as many tourists as the current number of tourists.  相似文献   
25.
Liquid-solid phase de-t-butylation of p-t-butylphenols was carried out over original and dealuminated zeolites to determine the effect of catalyst pore size and acidity on the reaction rate and catalyst fouling rate. The de-t-butylation rate over the original zeolites was mainly dependent upon their micro pore sizes. Although the dealumination by acid leaching decreased strong acid sites, the de-t-butylation rate over dealuminated HY zeolite was higher than that on the original zeolite. The present dealumination is a useful method to prepare an acid catalyst for de-t-butylation in a liquid-solid system.  相似文献   
26.
介绍了一种基于统计学假设检验理论进行模式识别中的特征评价与选择的方法,该方法理论意义比较清楚,计算简单,能够选出合适的特征,其实现是采用统计学中t检验方法来进行的,即用检验各组样本特征之间差异是否显著,来评价所提取的特征值的优劣;采用启发武方法和判别分析来进一步考察所提取的特征值的分类效果.实现了超声回波特征空间的降维处理与最佳特征子集选择。  相似文献   
27.
The reersible association and dissociation of starch chain populations obtained from acid-treated starches (ATSs) was investigated. Potato starch, both nonglutinous and glutinous rice starches and sago starch were suspended in 15% sulfuric acid until 1% hydroysis occured. These ATSs had relative molecular weight ranges of 25,00–29,000 daltons. In water, about half the molecules were reconstituted into large aggregates of a few million daltons. This change in molecular size depended on presence of potassium chloride. It was not observed in debranched samples. The aggregates showed a clear endothermic peak on a DSC curve. Thus, the reversibly rearranging starch chain populations were not linear, but were branched and had some type of ordered structure.  相似文献   
28.
Various biochemical parameters measured in sockeye salmon, Oncorhynchus nerka, feeding in the Gulf of Alaska in July during the maturation process were contrasted with those obtained from mature sockeye salmon in Steep Creek, a small salmon stream near Juneau, Alaska. Degenerative changes in muscles, such as decrease in total lipid and protein contents in mature salmon were attributed both to the progressed activation of lipid hydrolytic enzymes and to autolytic activity, in addition to the inactivation of lipid and protein syntheses in muscle and liver. The depletion of lipid is associated with the energy utilization for migration and gonadal maturation as a result of the cessation of feeding.  相似文献   
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SUMMARY— As morphological changes occurred in the pectoral muscles of chicken carcasses during 48 hr storage at 5°C, two notable phenomena were observed: (1) fragmentation of myofibrils and (2) reversible or irreversible contraction of sarcomeres. When blendorized, myofibrils tend to break into small fragments composed of 1-4 sarcomeres with time post-mortem. It was also found that besides an irreversible post-mortem contraction of sarcomeres generally accepted, a reversible contraction can take place under particular conditions.  相似文献   
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