氮化的

The masking effect of the sodium azide solution on the interference of chloride and nitride was verified.

试验验证了叠氮化钠溶液对氯化物、氮化物干扰的掩蔽作用。

The diazotization condition of 4-methyl-1-ethyl-3-cyano-5amino-6-hydroxy-2-pyridone and coupling condition of its diazo salt were researched, and the structure of its diazo salt was confirmed.

研究了4-甲基-1-乙基-3-氰基-5-氨基-6-羟基-2-吡啶酮的重氮化反应及其重氮盐发生偶合反应的条件，确定了重氮盐的结构。

The soil nitrogen status is a function of the processes of nitrogen fixation , microbial decomposition, nitrification and denitrification

土壤氮状况是一个固氮、微生物分解、硝酸化和脱氮过程的作用。

The inhibitor for DNA methyltransferase, 5-azacytidine (5-azaC), can demethylate the methylated DNA and restore transcription of genes. High dose homocystine can mediat DNA methylation and suppress gene expression.

应用甲基转移酶抑制剂5-氮杂胞苷(5-azacytidine， 5-azaC)可以使甲基化的启动子去甲基化，启动基因重新转录；高浓度同型半胱氨酸(homocystine， Hcy)可以介导基因甲基化而抑制其表达。

The utilization rate of N fertilizer of the former was significantly lower than that of the later, and the contribution of soil mineralizable N was relatively higher in the former, compared with the later.

前者对肥料氮的利用率较后者显著地低，且土壤矿化氮在所吸收的氮中的贡献率也相对较高。

Through diazotization-lactonization,esterification, reduction, ether formation and double bond formation,the optically active--γ-benzyloxy methy-γ-butanolideXXIII and--γ-benzyloxy mothy-γ- butenolideXXV were preparedstarting from L-glutamic acid.

本论文采用易得的L-谷氨酸为原料，经重氮化-内酯化、酯化、还原、醚化和形成双键五步反应，合成了光学活性的化合物XXIII和XXV(Scheme 6，P.63)。

The diblock copolymer of styrene and chloromethyl-4-vinyl-benzene was obtained by means of reverse addition fragmentation chain transfer reaction living free radical polymerization. The chloromethyl groups in PS-bPCVB were transformed into azidomethyl groups, and then into 1,2,3-triazol groups via click chemistry. The diblobk copolymer containing 1,2,3-triazol groups was thus obtained. The results from NMR spectra suggested a complete transformation from chloromethyl groups to triazol groups.

通过RAFT活自由基聚合方法制备聚（苯乙烯-b-对氯亚甲基苯乙烯）二嵌段共聚物，其中的氯亚甲基侧基经叠氮化反应后与丙炔醇进行点击反应，最终获得了含有1，2，3-三氮唑官能团的聚苯乙烯二嵌段共聚物，核磁共振谱表征结果证明，PS-b-PCVB中的氯亚甲基完全转变成了1，2，3-三氮唑基团。

The diblock copolymer of styrene and chloromethyl-4-vinyl-benzene was obtained by means of reverse addition fragmentation chain transfer reaction living free radical polymerization. The chloromethyl groups in PS-b-PCVB were transformed into azidomethyl groups, and then into 1,2,3-triazol groups via click chemistry. The diblobk copolymer containing 1,2,3-triazol groups was thus obtained. The results from NMR spectra suggested a complete transformation from chloromethyl groups to triazol groups.

通过可逆加成－断裂链转移聚合活性自由基聚合方法制备了聚（苯乙烯－b-对氯亚甲基苯乙烯）二嵌段共聚物，其中的氯亚甲基侧基经叠氮化反应后与丙炔醇进行点击反应，最终得到了含有1，2，3-三氮唑官能团的聚苯乙烯二嵌段共聚物，核磁共振谱表征结果证明，PS-b-PCVB中的氯亚甲基完全转变成了1，2，3-三氮唑基团。

Compounds 3a-3d, 4a-4d, 5a-5d, 6a-6e and 7a-7e were prepared with a new efficient method, in which the aromatic amines were diazotized with isoamyl nitrite in EtONa/EtOH under refluxing condition, and mono -, bis -and tetrakis -substituted calix [4] arenes were obtained respectively as main product by diazo-coupling in different molar ratio to calix [4] arene.

一，提出了一个有效的新方法合成含有芳香偶氮基团的杯[4]芳烃衍生物3a-3d；4a-4d；5a-5d；6a-6e和7a-7e：即在非水溶剂乙醇中用亚硝酸异戊酯，在强碱乙醇钠存在下对芳香胺进行重氮化，得到芳香重氮酸盐沉淀，过滤，然后加入杯[4]芳烃的四氢呋喃溶液，通入CO〓气体调节溶液的pH值为7-9，使其发生偶联反应。

Transition metal borides and inorganic boron-containing compounds, such as TiB〓, BN, B〓C and BP, are one of the most important groups for application in high-temperature performance, electronics and catalysts. Traditionally, they were prepared by high-temperature reactions; however, the products were beyond nanometer scale.

中文题名溶剂热合成硼化物及非金属含硼化合物纳米材料副题名外文题名论文作者谷云乐导师钱逸泰学科专业无机化学研究领域\研究方向学位级别博士学位授予单位中国科学技术大学学位授予日期2003 论文页码总数70页关键词纳米材料硼化物溶剂热合成馆藏号BSLW /2003 /O613 /6 硼化物、非金属含硼化合物功能材料（如硼化钛、氮化硼、碳化硼和磷化硼等）通常具有高硬度、高熔点、机械强度大、高温化学稳定性好等一系列优良性能，有些还具有奇异的光、电、磁、热学性能和催化活性，是一类最富潜力的非氧化物高温结构材料、电子材料和催化材料。

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