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81.
82.
通过对金融生态主体:政府、金融缉织、非及金融组织的行为倾向进行分析,在心里学与利益制衡范畴解释其行为动机,和这一动态演进过程造成的结果。然后,模拟金融生态主体博弈过程,借助其在社会范围之内的相互联系、相互影响、共同作用,反过来影响和形成了短期社会规则,并影响金融生态的长期构建。  相似文献   
83.
A technique of fabrication of air electrode for direct methanol fuel cells (DMFC) is proposed. The investigated air electrode is free of Teflon- containing and with ultra- thin catalyst layer. Catalysts PtRu/C for methanol electroxidation is electrochemically deposited on a Nafion- bonded carbon electrode. A concept, that is, methanol is oxidized at a relatively high potential, is proposed. Such a fabricated DMFC is characterized with a high utilization of noble metals and basically eliminating CO poisoning in operation.  相似文献   
84.
沿河山羊舍饲养殖试验研究   总被引:1,自引:0,他引:1  
通过对沿河山羊进行舍饲养殖试验研究,结果表明沿河山羊在舍饲环境条件下其发情规律、怀孕期均与放牧山羊基本一致.舍饲母羊胎均产羔率为187.88%,略高于放牧母羊产羔率(184.85%).舍饲羔羊断奶成活率为88.71%,比放牧羔羊断奶成活率(81.97%)提高8.22%.舍饲山羊发病死亡率为12.50%,比放牧山羊低76.54%.舍饲羔羊公母平均初生重为1.71±0.57kg,2月龄体重为8.88±1.64kg,6月龄体重为17.85±2.69 kg,9月龄体重为27.37±3.32kg,比放牧羔羊分别提高1.79%、27.95%、26.78%和26.16%,除羔羊初生重相接近外,其余各月龄阶段的体重差异均极显著(P<0.01).舍饲羔羊各月龄阶段的体高变化不大,体斜长、胸围均有明显提高,增长幅度在10%以上,差异显著(P<0.05).可见,沿河山羊在舍饲环境条件下具有良好的适应能力,而且舍饲还有利于疫病的防治,促进生长发育,值得在全县范围内推广.  相似文献   
85.
The separating characteristic of element in cumulate MSW is a very important base to investigate the synthetically managing technology and estimate the water environment effects in Three Gorge Reservoir (TGR). The experiment to marinate the cumulate MSW under 135 meters for TGR in water is finished, and the same time, the Separating Distributing Coefficient (SDC) and the Separating Velocity Rate (SVR) of each heavy metal in water are presented, too. The experiment results show that the SDC of Cd is the smallest, the Ratio for Water and MSW (RWM) and marinating time play an important role in SDC and SVR, the SDC and SVR change smaller while the RWM get to 400, the separating content of heavy metal can reach 0.75 during three weeks, SVR decreases more with marinate time's increasing, and SVR gets an limit value with smaller RWM. The results can be a base for deeply studying the managing technology and the cumulate MSW under 135 meters for TGR.  相似文献   
86.
To be effectively heated in incinerator for MSW is very important for stabilization and completeness combustion, the smaller produce of the PCDD/Fs. At the same time, the transient heat transfer characteristics of the MSW lump decides the stay time of the MSW in incinerator and effects on the operation feature of the combustion equipments. All of these would lead to design the reasonable and clean combustion project, the optimum incinerator and recover energy system. The component, shape, dimension, property, the hardly and inner structure feature of the MSW lump are taken in account, and the effective conduct heat coefficient has been adopted. And then, the physical model is setup with different shape(ball, cylinder, squareness), and the 3-D mathematical model and conduct heat efficient with porous feature for transient heat transfer of MSW lump are presented, at the same time, the simulation tests are gotten in various boundary and the interesting conclusions are gotten: The center stable temperature of the MSW lump is mostly decided by the inner gas temperature of the incinerator and the heated area of the lump. The transient heat transfer characteristics is variously effected by the shape of the MSW lump in incinerator. The transient process becomes longer and the center stable temperature decreases, the volatile can't be easily separated out and the combustion efficiency decreases because of the increasing of the lump feature dimension.  相似文献   
87.
88.
Design and Experimental Analysis of Silicon Oil Clutch   总被引:12,自引:0,他引:12       下载免费PDF全文
采用热水浸提、醇沉法提取红枣多糖,对红枣多糖提取工艺与一般理化性质进行了研究.选择浸提固液比、温度、时间和浸提次数作为单因素进行梯度实验,确定其条件范围,再通过正交实验L9(33)进一步确定红枣水溶性多糖最佳提取工艺条件.结果表明,最佳提取工艺条件为:固液比1:7,浸提温度80℃,浸提时间2 h,反复浸提2次.理化性质研究结果表明,提取的红枣多糖中含有多肽和AA,为蛋白质复合多糖.  相似文献   
89.
90.
液体培养研究不同土壤中硝化活性   总被引:2,自引:0,他引:2  
YUAN Fei  RAN Wei  SHEN Qi-Rong 《土壤圈》2005,15(3):379-385
A red soil, a fluvo-aquic soil and a permeable paddy soil were used in a long-term investigation to study changes in nitrification with treatments: 1) soil incubation, 2) liquid incubation inoculated with soil samples, and 3) liquid incubation inoculated with ammonia-oxidizing bacteria (AOB) from the soils. There were significant differences (P < 0.001) in nitrification rates among the three soils when measured for 28 days by adding (NH4)2SO4 at the rate of 154 mg N kg-1 dry soil to fresh soil. However, the amounts of nitrifying bacteria in the three soils were not related to soil nitrification capacity. When the soil samples or the isolates of AOB enriched from the corresponding soil were incubated in liquid with pH 5.8, 7.0 and 8.0 buffers and 10 mmol L-1 ammonium nitrogen, there were no significant nitrification differences in the same soil type at each pH. The ability to oxidize ammonia through AOB from different types of soils in a homogeneous culture medium was similar, and the soil nitrification capacity could reflect the inherent properties of a soil. Altering the culture medium pH of individual soil type also showed that acidification of an alkaline fluvo-aquic soil decreased nitrification capacity, whereas alkalinization of the acidic red soil and permeable paddy soil increased their nitrification. For a better insight into factors influencing soil nitrification processes, soil properties including texture and clay composition should be considered.  相似文献   
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