前体物

Arg是多胺、肌酸和一氧化氮等的直接前体物，可对动物机体血管再生产生积极效应，并最终改善氮代谢、繁殖、泌乳、免疫和动物的生长性能。

As a precursor of polyamines , creatine and nitric oxide ( NO ), it exerts many beneficial effects on animal body and enhance angiogenesis , lactogenesis , finally leading to the improvement in nitrogen ( N ) metabolism , reproduction , lactation , immunity and growth of animals .

中国烤烟主要香气前体物的研究

Studies on the Chiefly Fragrant Precursor of the Flue-cured Tobacco in China

研究了用Fe（CO）5为前体物，在喷动流化反应器中对云母粉包覆铁氧化物制备铁系珠光颜料的新工艺。

Iron oxide-mica pearlescent pigment was prepared by Fe ( CO ) 5 in a spout-fluidized bed using MOCVD technique .

制备溶液pH对CuO-ZnO/Al2O3催化剂前体物相及其CO水汽变换反应活性的影响

Influence of Precipitation pH on Phase Composition of Catalyst ( CuO-ZnO / Al_2O_3 ) Precursors and Activity of Catalyst in CO Water Gas Reaction

污水厂二级出水中THMs前体物卤代活性荧光光谱分析

Fluorescence characterization of the reactivity of THMs precursors in secondary effluent

在SAT中，溶解性有机物（DOM）由于是回用水加氯消毒过程中具有致癌性的消毒副产物（DBP）的前体物而备受关注。

Dissolved organic matter ( DOM ) is of concern during the SAT because it could potentially be converted to potentially carcinogenic disinfection by-products during the disinfection process .

胰激肽原酶（pancreatickininogenase）是一种催化大分子前体物释放生物活性肽的酶。

Pancreatic kininogenase ( PK ) is an enzyme which can serve as a catalyst to help macromolecular precursors release bioactive peptide .

氮用量对烤烟叶片TSNA前体物含量及硝酸还原酶活性的影响

Effects of nitrogen level on TSNA precursors content and nitrate reductase activities in flue-cured tobacco

不同基因型烤烟烟叶中TSNA与其前体物的研究

Study on the Tobacco-specific Nitrosamines ( TSNA ) and Their Precursors in Different Flue-cured Tobacco Genotypes

局地光化学生成是白天边界层O3的主要来源；降水天气过程可造成O3及其前体物浓度的显著变化。

It was also found that the photochemistry reaction was an important source in boundary layer in daytime and precipitation process could arouse marked change of O3 concentration .

光化学烟雾和大气臭氧形成的重要前体物之一&非甲烷烃（NMHC）的排放受到研究者的热切关注。

As one important predecessor of photo-chemical smog and ozone , non-methane hydrocarbon 's ( NMHC ) emission is paid great attention .

烟叶和烟气中TSNAs的含量分析及其与前体物的关系

The Concentration Analysis of Tobacco-Specific Nitrosamines in Tobacco Leaves and Tobacco Smoke and the Relationship with Its Formers

本文通过大量细致的实验，深入研究了大气中VOCs形成SOA的反应机制；探讨了某些SOA的前体物与大气中氮氧化物的化学反应。

The mechanism for SOA formation via VOCs in air has been investigated extensively through a series of carefully designed experiments . Additionally , the chemical reactions of some precursors of SOA with nitric oxides in atmosphere have also been studied .

VOCs不仅对人体有明显的毒性效应，同时也是城市和区域大气化学反应的重要前体物，对大气氧化潜势有重要影响。

VOCs not only have significant toxic effects on human body , but also are the precursor materials of urban and regional atmospheric chemical reactions which have a major impact on atmospheric oxidation potential .

对Mailard反应体系中风味前体物及工艺条件对热反应鸡肉风味的影响进行了研究，并确定出温和Mailard反应改善鸡肉风味的最优水平为：温度95℃；时间100min；

Effect of flavor precursors and technology on the chicken flavor is studied .

闽南地区降水的SO2－4／NO－3比值是我国主要酸雨区中最低的，NOx是闽南地区酸沉降形成的重要致酸前体物之一；

The ratio of SO 2 - 4 to NO - 3 of rainwater in Minnan area is the lowest among those in main acid areas of China ; NO x is one of the most important precursors of acid rain ;

它是一种叶酸依赖性酶，是合成DNA所必需的前体物胸腺嘧啶脱氧核苷（dTMP）的关键酶，在细胞增殖中起重要的作用。

Thymidylate synthase ( TS ), as a folate-dependent enzyme , is essential to cell proliferation since it is the key enzyme which catalyzes the de novo synthesis of thymidine ( dTMP ) of DNA precursor .

采用强化混凝去除DBPs前体物是最佳可行技术（BAT），建立DBPs生成预测模型并加以实用化是今后研究的重点。

The best available technology ( BAT ) to remove the formation potential of DBPs is enhanced coagulation . It is important to establish the predictive model for DBPs and to practise in the future .

了解这些前体物的遗传变异特性，对通过遗传改良途径降低烟叶中TSNA含量、提高烟叶品质与安全性具有重要的意义。

It is of great importance to know genetic variation of these precursor in decreasing the TSNA content and improving the quality and safety of tobacco leaves by genetic improvement .

我国主要采用前体物试验（FP试验）对饮用水中消毒副产物（DBP）的形成进行评估，但这种方法无法对配水系统中DBP产量进行评估。

In China , the formation potential ( FP ) test was mainly used to assess the disinfection byproduct ( DBP ) in drinking water , but the test failed to assess the DBP production in water distribution system .

为全面了解我国烟叶原料及卷烟制品中烟草特有亚硝胺（TSNAs）的含量和分布情况，本文对烟叶和烟气中的TSNAs作了含量分析及其与前体物关系的相关研究。

The object of this paper was to understand the real condition of Tobacco-Specific Nitrosamines ( TSNAs ) in tobacco leaf and in different cigarette brands .

为便于理解O3与其前体物之间的复杂非线性关系，人们发展了一些可基于观测取得的指标，臭氧生成效率（OPE）属于其中较为常用的一种指标。

To facilitate the understanding of the complex nonlinear relationship between O3 and its precursors , some observation-based indicators have been developed ; with ozone production efficiency ( OPE ) being one of the common indicators .

应用大气光化学模式研究了日最大臭氧体积分数及其出现时刻与其前体物NMHC、NOx体积分数及NMHC/NOx比值的关系。

The relations of the diurnal peak of photochemical ozone and its occurring time to the ozone precursors ( NMHC , NOx ) and the ratio of NMHC / NOx are researched by using an atmospheric photochemical box model .

本文根据饮用水的NO-3分析资料，阐明了亚硝胺的前体物NO-3的分布与食管癌的地理分布具有明显的相关性。

The geographical distribution of NO - 3 and esophagus cancer possesses obvious correlation from analytical data for drinking water NO - 3 of samples in this paper .

自来水加氯消毒副产物及其前体物（THMFP）的研究与发展饮用水加氯消毒副产物及其控制技术的发展

Advances on chlorinated disinfection by-products like trihalomethanes and their formation potential in drinking water Development of disinfection by products research and its treatment and control technology

利用溶液前体物组合化学方法研究了La-Ca-Mn-O的相关系。

The phase relationship of La Ca Mn O system has been studied by combinatorial chemistry technique using solution as the precursor .

2000年夏季7~8月，以北京325m气象塔为观测平台，分别在8120280m高度上进行了大气污染物臭氧（O3）及其前体物氮氧化物（NOx）和气象要素加强期的同步观测。

Based on the Beijing 325 m meteorological tower , O3 , NOx atmospheric pollutants and meteorological essential factors in strengthened period were observed synchronously from July to August of year 2000 on 8 , 120 and 280 m high levels respectively .

通过红霉素耐前体物的筛选，选到了一株红霉素的高产变株F1-57，其发酵水平较亲株提高10%以上。

An Erythromycin productive high-yielding mutant F1-57 was screened by the test of precursor tolerance . The fermentation yield of which is 10 % more than that of parental strain .

结果表明，水中较高浓度的NO-2-N可消耗臭氧投加量的40%左右，并降低了臭氧对THMs前体物的去除率，也影响其提高水中可生物降解有机物浓度的能力；

The results show that high concentration NO-2-N in water can consume ozone dosage by 40 % and reduce the removal rate of THMs precursor and the enhanced degree of biological degradation ability of water after ozonation .

按一定顺序在原水中投加少量Fenton试剂和粉末活性炭，可在保证常规出水水质指标的情况下，有效去除三卤甲烷前体物（THMFP），从而大大降低饮用水中三卤甲烷的浓度。

Under the condition of guaranteeing conventional water quality parameters , the trihalomethanes formation potential can be removed effectively when small quantity of Fenton reagent and powered activated carbon are added in the certain dosing sequence in raw water to greatly decrease the concentration of trihalomethanes in the drinking water .