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The purpose of the paper is to elucidate the biological effect of benzene on the basis of benzene constitution, quantum chemistry and quantum biology. In addition, we also have examined the toxicological mechanism of benzene in view of action of benzene on energy.  相似文献   

3.
MolecularBasisofTransferofInducedResistanceinPlants*XuWenlian(徐文联),DongHansong(董汉松)+,PanJun(潘军)+,JiangWuling(蒋五玲),LiuAixin(刘爱...  相似文献   

4.
The occurrence of toxic water bloom of cyanobacte-ria algae, widely reported in eutrophic freshwater, hasbeen a serious pollution problem in recent years[1]. Mi-crocystins (MCs), the most common cyanobacteriatoxin with a cyclic heptapeptide structure (Fig…  相似文献   

5.
UltrastructureofHepatopancreasCelsofMacrobrachiumnipponensisWangWeinaWangAnliWeiXuanhuiGuoMingshen(DepartmentofBiology,HebeiU...  相似文献   

6.
The orientation between the backbone residues of proteins is defined based on the local configurations and the corresponding preferences are analyzed by statistics.It is found that all the residue pairs have some specific preferences of orientations.The statistical analysis is mainly concen-trated in the orientational distributions for two kinds of groupings of residues based on the hydrophobicity and secondary structural features.The statistics for such two types of groupings shows different orienta-tional preferences.It is found that for the former grouping the orientational preference is rather weak, while for the later a kind of strong orientational pref-erences.This suggests that the formation of local structures and of secondary structures are highly related to the orientational preferences.  相似文献   

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completed.□ Lemma2 .2  Suppose H to be a Hilbert spacewith the inner product ( .,.) H and the relativenorm‖·‖H.If{xn}in H weakly converges tox,then there exists a subsequence {xni}satisfyingthatx - 1k ki=1xni H→ 0 ,  k→∞ . The proof can be found in Ref.[9].  Lemma 2 .3  Suppose W* to be a symmetricform on D[W],and W* [u]≤ W1[u]for all u∈D[W].If {un}∈D[W]in H converges W1- weak-ly to u,then it converges W* - weakly to u. The proof can be found in Ref.[8].  Lemma 2 .4…  相似文献   

9.
Glaciers are extensively developed in the southwest of Tibet and the moraines are widely distributed with large depth. Large-scale debris flows are often reported which blocked rivers and formed dams. In this paper, seven large debris flows in four valleys are discussed, among which five dams developed. 13 sets of experiments have been conducted in laboratory to simulate the formation and failure of the dam. Finally, a model of dam failure is proposed and a formula is established to calculate the flood discharge: Q=kbnnk/TB^-/LG^0.1,where bk is the outlet width of the dam at the original water level, hk the erosive depth, T the time from overflow to final state of failure, the average width of lake; L the length of the lake, and G the total potential energy of the water in the lake.  相似文献   

10.
The indirect release of chemical energy of fuel is investigated, and a new mechanism is proposed to identify the cascade utilization of chemical energy of fuel more clearly. Based on the concept of energy level, the internal phenomenon of the indirect chemical energy release is disclosed, and the equations of energy level describing the utilization of chemical energy and thermal energy during the indirect chemical energy release process are obtained. From theoretical analysis, we find that the superiority of the indirect chemical energy release of fuel comes from the cascade utilization of the fuel's chemical energy. Moreover, the cascade utilization of chemical energy is verified by the investigation of CRGT (chemically recuperated gas turbine). As a result, the thermal exergy obtained from the chemical energy release of fuel increases by 2%?3%. The results obtained here may help a deeper understanding of indirect chemical energy release of fuel and provide a theoretical basis for the synthesis of innovative energy systems.  相似文献   

11.
研究了国家法的抽象正义观与民间法的情理正义观,认为西方国家法的抽象正义观与东方民间法的情理正义观存在实质的不同,原因在于思维方式、超验与经验传统、政治结构的差别。在现代法治理念下,传统民间法所代表的正义观将向混合正义观转型,西方法治所代表的国家法抽象正义观是其骨架。  相似文献   

12.
图集的统一协调,对图集质量有很大影响。本文是作者在编制北京市农业区划地图集的实践基础上,根据地图信息传输论的观点,对农业区划地图集的统一协调的内容及方法进行了探讨。试图总结编制这类图集的统一协调模式,以供读者编图时参考。  相似文献   

13.
利用对位异构体的对称性由核磁共振氢谱测定了工业十二烷基苯在硝硫混酸中的硝化选择性,发现一硝化产物中对位异构体的比例为75% ̄80%。以月桂酸和苯为原料,经氯化、酰化和还原合成了正十二烷基苯。在同样条件下研究了正十二烷基苯的硝化,由核磁共振氢谱和气相色谱分析,发现一硝化产物中对位异构体的比例仅为60%。根据空间位阻效应,对结果进行了讨论,并与甲苯,乙苯,异丙苯等短链烷基苯的硝化结果进行了比较。  相似文献   

14.
YBCO掺杂效应研究   总被引:3,自引:0,他引:3  
介绍了YBCO掺杂的基础知识,总结了YBCO各个位置采用典型元素掺杂而导致的超导电性和结构的变化,阐述了掺杂对YBCO的重要影响,并简介了当前YBCO掺杂效应研究中的几个热点问题.  相似文献   

15.
为了找出诱发高频机组基础不良振动的原因,从基础计算模型方面对基础激励与响应进行了分析,以两个高频机组基础为动测实例,经模态分析得出钢筋混凝土构架式基础竖向1阶振动与电机产生共振;应用功率谱法对动力机组及基础平台进行动测,得出平台异常响应频率66Hz为水泵工作频率,调整机器的工作频率可避开不良振源影响,达到明显的减振效果。由此而知,动力机器基础出现不良振动时,不可盲目改变结构的动力特性,应在机器不同工况比如:停机、起机及正常转速下,对机器及基础进行动测并对振动信号进行比较分析,以制定出行之有效的减振方法。  相似文献   

16.
老年人生活空间移动性影响要素研究进展   总被引:1,自引:0,他引:1  
 老年人生活空间移动性是老年人在日常生活中能动生活状态的重要表征。在梳理老年人生活空间移动性相关概念、测度方法基础上,分析了物质环境要素和非物质环境要素对老年人生活空间移动性的影响;提炼出有效支持老年人生活空间移动性的中观环境规划、微观环境设计和政策文化扶助层面的策略;指出了老年人生活空间移动性的研究建议和发展方向。  相似文献   

17.
给出整数幂的和的另一种计算公式的方法.  相似文献   

18.
曲面“侧”是一个重要而难以理解的概念 ,本文对曲面“侧”概念的讲授方法进行了探讨 ,给出了曲面“侧”概念的“参照物”理解法 ,通过实践证明 ,效果良好。  相似文献   

19.
给出了一维非自治时滞系统点态退化的一个例子,拓宽了该领域的研究。  相似文献   

20.
宏观收入量的分配不仅反映一个国家总体消费的基础水平,而且影响到各阶层消费水平及消费方式.虽然一个国家的宏观收入量的分配不可能绝对平等,但是不等性的大小往往影响到社会和经济的发展,影响到社会的稳定.本文采用洛伦茨曲线、基尼系数来描述宏观收入的不等性,并结合实际情况对我国宏观收入的不等性进行了具体的分析.  相似文献   

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