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In chapter 4, Based on the orthogonality relations and duality of C-algebras, we study the decompositions of C-algebras, and give a Fourier inversion formula on C-algebras, which generalizes the Fourier inversion formula on the center of a finite group algebra over complex. As an application, we characterize the integral closure of C-algebras over the ring of integers, and show a necessary and sufficitient condition for elements of C-algbras being algbraic integral over integers.

第四章 我们应用C-代数的正交性及对偶性刻画了C-代数的一个分解，给出了C-代数上这个完全分解的Fourier反演公式，从而推广了Z分解的Fourier反演公式；作为Fourier反演公式的一个应用，我们刻画了Z在整数环Z上的整闭包，进一步我们研究了C-代数在整数环Z上的整闭包，给出了C-代数在整数环Z上为整元的一个充要条件。

The dissipation factor tip-up D tan d , the change of capacitance D C / C 0, the maximum discharge q max and the mean discharge magnitude q mean , A compared investigation of the correlations between V min , V av and service time were compared with those between D tan d , D C / C 0, q max, q mean and respectively.

对大量的不同运行年数的线棒进行了超声波 V min 和 V av 测量，以及介质损耗角增量 D tan d 、电容变化率 D C / C 0、最大放电量 q max 和平均放电量 q mean 等电气测量试验，对比研究了超声参数( V min 和 V av )和电气测量参数( D tan d 、 D C / C 0、 q max 和 q mean )与运行年数的相关性，发现， V min 和 V av 与的相关性很强，相关系数 R 分别为0.892和0.890，而 D tan d 、 q max 和 q mean 与的相关性较弱， R 在0.55~0.60范围内， D C / C 0与几乎没有相关性， R 仅为0.310；采用线性回归分析，分别建立了 V min 和 V av 与的二阶和三阶线性函数的数学模型， R-S 分别为0.828和0.903，并分别提出了最可靠运行年数和置信度为95％的可靠运行年数的预测方法。

In this thesis,the AM1,MNDO,MINDO/3(mainly AM1)and INDO/S-CI semiempirical MO methods were used toinvestigate the excited-state intramolecular protontransfer reactions of salicylic acid derivatives—salicylic acid,methyl salicylate,salicylaldehyde,o-hydroxyaceto-phenone,salicylamide and 3-hydroxy-picolinamide (6 conformers and 2-3 anion species);2-(2'-hydroxy-5' methylphenyl) benzotriazole(4 conformers),2-(2' hydroxyphenyl) benzimidazole (3 conformers and 3anion species),Bis-2,5-(2-benzoxazolyl)hydroquinone(3 conformers),2-(2'-hydroxyphenyl)benzothiazole(2conformers) and 7-azaindole dimer (2 conformers).Theinvestigations were described as follows.Geometry optimization,relative stability andhydrogen bonding energy First,for sylicylic acid derivative molecules,the AM1,MNDO and MINDO/3 methods were used toinvestigate ground-state geometry optimization,energies,relative stabilities and hydrogen-bondingenergies on the five kinds of the molecules(designing 6 conformers and 2-3 anion species).Comparing with experimental data,the optimizedgeometry,the order of stability,the hydrogen-bonding energies and the distances between O-O in O-H..O hydrogen bonds by AM1 method were in agreementwith the experimental data,however,the C-C bondlengths optimized by MNDO and MINDO/3 were longer,C-O and O-H bond lengths were shorter;for C-N bondlengths,the results opitimized by MNDO method werethe same as those by AM1 method,nevertheless the C-Nbond lengths given by MINDO/3 method were muchshorter.For some sylicylic acid derivatives(e.g.methyl salicylate,salicylamide),the order ofstabilities on the conformers given by MNDO andMINDO/3 methods were not in agreement with theexisting conformers deduced by experimental methods,and the hydrogen bonding energies calculated by MNDO.and MINDO/3 methods were smaller.Second,the studyon the other systems found that the optimizedgeometry of the proton-transfered product with INDOmethod could not be obtained,only could theoptimized geometry of reactant be obtained,and thecalculated hydrogen bonding energies were greater.Many results of calculation indicated that the studyon the excited-state intramolecular proton transferreaction system using AM1 method was suitable andreliable.

本论文用AM1、MNDO、MINDO/3（主要是AM1）和INDO/S-CI半经验分子轨道方法对水杨酸衍生物系列——水杨酸、水杨酸甲酯、水杨醛、O-羟基乙酰苯酮、水杨酰胺和3-羟基吡啶酰胺（6种异构体和2-3种阴离子）；2-（2'-羟基-5'-甲基苯基）苯并三〓唑（4种异构体）；2-（2'-羟基苯基）苯并咪唑（3种异构体和3种阴离子）；2，5-二间氮杂氧茚氢醌（3种异构体）；2-（2'-羟基苯基）间〓杂硫茚（2种异构体）和7-〓吲哚二体（2种异构体）的激发态分子内质子转移反应在以下几个方面进行了较系统的理论研究：几何构型优化和相对稳定性及氢键能首先以水杨酸衍生物系列分子为例，用AM1、MNDO和MINDO/3方法考察了5种分子（每种分子设计6种异构体和2-3种阴离子）的基态几何构型优化，能量、相对稳定性和氢键能计算，通过和实验数据进行比较，AM1方法给出的优化几何构型、稳定性次序、氢键能和O—H。。。O氢键的0—0距离与实验数据吻合最好，MNDO和MINDO/3方法优化的C-C键长偏长，C-O键和O-H键长偏短；对于C-N键长，MNDO和AM1优化结果差别不大，而MINDO/3给出了过短的C-N键长，MNDO和MINDO/3方法给出的有些水杨酸衍生物分子（如水杨酸甲酯和水杨酰胺）异构体的稳定性次序和实验上推测的可存在异构体结果不一致，MNDO和MINDO/3方法给出的氢键能偏低，对其他体系的研究发现INDO方法常常不能得到质子转移产物的优化几何构型，只能得到反应物的优化构型，并且估算的氢键能偏高，大量的计算结果表明AM1方法对本论文研究的激发态分子内质子转移反应体系是适宜和可靠的。

Floral organ determination is best explained by the ABCDE model postulated by genetic studies of Arabidopsis thaliana. Sepals are determined by A and E class genes; petals are determined by A, B, and E; stamens by B, C, and E; and carpels by C and E class genes. A, B, C, and E class gene lineages are known having duplicated several times during the evolution of angiosperms. One of the noted major duplication events occurred in the origin of the early angiosperms, leading to the formation of subgroups of B/C/D/E class. Another one occurred near the basal eudicots and gave rise to further subgroups in A/B/C/D/E class genes among core eudicots. The phylogenetic position of the family Buxaceae is located right where the second major duplication of ABCDE genes might have occurred, which is supported by multiple gene (nuclear 18S rDNA, chloroplast rbcL and atpB) phylogenetic analyses.

目前经由模式植物阿伯芥的研究，建花部器官决定基因的调控，即花萼由A、E 群基因共同决定，花瓣由A、B、E 群基因，雄蕊由B、C、E 群基因，而心皮由C 和E 群基因决定。A、B、C、E 四群基因在被子植物的演化过程中发生过次的复制事件，其中比较重要的一次发生在早期被子植物演化出之时，形成B/C/D/E 群基因的次系群；另一次复制事件则发生在真双子植物基群附近，形成仅於核心真双子植物的A/B/C/D/E 群基因之次系群。

Cu-C composite is one of the most potential materials for pantograph slide plate, which is an important component of pantograph system in locomotive. The principle of wettability between Cu and C was investigated in this paper. The element of Mo was selected to improve the wettability between Cu and C. The fabrication process of cold compression sintering fiber reinforced Cu-C composite and its effect on the composite property were studied. The wear and friction mechanism of Cu-C composite was investigated initially by electriferous friction test.

Cu-C材料是目前最具应用前景的电力机车受电弓滑板用材料之一，本文研究了Cu与C之间的润湿原理，利用Mo元素有效改善了Cu与C之间的润湿性；并对冷压烧结法制备纤维增强Cu-C复合材料的工艺过程及其对性能的影响进行了研究；通过带电摩擦试验对Cu-C复合材料带电摩擦磨损机理进行了初步探讨。

Deference was significant. 2. Levels of serum TC, TG and LDL-C in D group were higher than those in C group. Difference was significant. Levels of serum TC, TG and HDL-C in ErD group were higher than C group.

血脂代谢：D组大鼠TC、TG、LDL-C均高于C组，差异具有显著性；ErD组大鼠TC、TG、HDL-C均高于C组，差异具有显著性；LDL-C水平：D组＞ErD组＞C，三组之间差异均具有显著性。3。

The results of the investigation showed that the best entrance angle of B〓C, B〓C/ C and Al〓O〓/ C ceramic nozzles is 11°, 14°and 16°respectively. Erosion wear model has been put forward. The B〓C and B〓C/ C nozzles exhibited a stress fatigue induced removal process under the condition of umber emery erodent impacting, and a brittle fracture induced removal process under the condition of white emery and SiC erodent impacting.

建立了不同磨损机理下的冲蚀磨损模型，提出了喷砂嘴的磨损属于多冲蚀机理并存的复合冲蚀机制。B〓C和B〓C/C陶瓷喷砂嘴在棕刚玉磨料的冲蚀下，主要表现为应力疲劳断裂冲蚀，在白刚玉和SiC磨料的冲蚀下，主要表现为脆性断裂冲蚀。

The soil pH was found to be the main factor affecting BR formation of 14 C\|metsulfuron methyl among the basic properties of soil.(2)During the whole periods of the incubation,the 14 C\|BR of 14 C\|metsulfuron methyl in soils was mainly distributed in fulvic acid and humin.The relative percentage of 14 C\|BR in fulvic acid was higher than in humin,while the content of the 14 C\|BR distributd in humic acid only account for less than 1% of applied amount.

土壤pH是14 C 甲磺隆在土壤中形成BR的主要影响因子。14 C -甲磺隆在各类土壤中的14 C BR的最大值分别占引入量的 48 5%、46 5%、52 6%、1 9 3 %、49 7%、42 0 %和 46 5%；( 2 )在整个培养试验过程中，14 C 甲磺隆在 7种不同类型土壤中的14 C BR ，主要分布在富啡酸和胡敏素中，前者中的相对百分比大于后者，而在胡敏酸中的相对百分比较小。

The DRe differences among plants could be well differentiated by TP. The DRe., i.e. water retention, represented by TP, was used as a major index to identify the ability of plant drought tolerance. It was showed that C.arborescens Ecotype Wu was generally the most drought tolerant one except lower than C.arborescens Ecotype XJ which was the maximum in May, bore comparison with Zygophyllum xanthoxylum by estimating seasonally; C.latens Ecotype NX was significantlly lower than C.arborescens Ecotype Wu, the result was contrary to being known; C.arborescens Ecotype Kerqin was significantlly lower than Wu; XJ, the maximum in May, showed no else great difference to NX; C.lanata was high in April and not high afterwards, however its phenological phase presented visible changes as compared with the original life patterns in western America.

结果表明，华北驼绒藜(C.arborescens Ecotype Wu)总体上表现出最强的耐旱性；宁夏驼绒藜(C.latens Ecotype NX)耐旱性显著低于华北驼绒藜；科尔沁驼绒藜(C.arborescens Ecotype Kerqin)耐旱性显著低于华北驼绒藜；新疆驼绒藜(C.arborescens Ecotype XJ)5月耐旱性表现最强，其他时间与宁夏驼绒藜差别不大；北美驼绒藜4月拐点很高，4月以后耐旱性降低，其物候期与原分布区相比发生了很大变化。

Comparing with marine oils in the adjacent areas, all crude oils in Hade 4 oil field (except for HD401 well) have following peculiarity: very similar in the composition of light hydrocarbon fraction, and the distribution of of phytane-series isoprenoid alkanes, high concentration in steranes, terpanes and their aromatized compounds, as well as rearranged steranes; low concentration of gammacerane, 24-norcholestanes and 24-rearranged steranes, and low C��� regular steranes C���/(C���+C���+C���＜20%; 3-methyl steranes and 27-norcholestane predominated, respectively; very low concentration of dinosterane and 4-methyl steroid.

分析表明，与相邻地区海相原油比较，除最南端的HD401井原油外，其它井区原油均具有下述特点：轻烃馏分组成十分接近、植烷系列类异戊烯烷烃分布较为一致、甾萜类和芳香甾萜类环状化合物浓度较高、重排甾烷丰度较高、伽马蜡烷含量低、规则甾烷组成中C〓丰度低C〓/(C〓+C〓+C〓＜20％、甲基甾烷中以3-甲基甾烷为主、甲藻甾烷和4-甲基甾烷丰度极低、降胆甾烷中以27-降胆甾烷为主、24-降胆甾烷和24-重排降胆甾烷丰度低。

In the negative and interrogative forms, of course, this is identical to the non-emphatic forms.

。但是，在否定句或疑问句里，这种带有"do"的方法表达的效果却没有什么强调的意思。

Go down on one's knees;kneel down

屈膝跪下。。。下跪祈祷