查询词典 substitution method

The thermokintics of nucleophilic substitution reactionsof benzoyl chloride and oxidation reaction of isopropanol by NBS have been studiedby using the mathematical models of the thermokinetic time-parameter method forsimple and consecutive first order reaction, respectively. The kinetic mechanisms ofstudied reactions have been discussed reasonably.

利用简单和连续一级反应的时间参量法的数学模型，分别研究了苯甲酰氯亲核取代反应和NBS氧化异丙醇反应的热动力学，对反应的机理进行了合理的解释和讨论。

This method make certain improvement on taking spots and selecting spells pastes; Then, analyze the existing two- Dimension IFS plant simulation the shadow-making technology, and make further improvements, by the linear substitution to the picture element, eliminated the phenomenon of tree"s shadow deviation tree body"s.

此方法在取点和选取拼贴方式两个方面都做了一定的改进；然后，分析了已有的二维IFS模拟植物的阴影绘制技术，并且对已有的阴影绘制方法作了改进，通过对象素点进行线性变换，消除了在绘制过程中树影偏离树体的现象。

The invention is a method for designing and preparing binary reinforced damping magnesium alloy having medium rigidity, medium strength, high-medium damping and medium raw material cost, the prepared alloy is beneficial for balancing required elements in practical application, including optimized rigid, wide frequency band, wide strain amplitude, wide temperature zone, strength, enough high-temperature-resistance, creep resistance, toughness, price, anticorrosion treatment and heat processing, and is beneficial for solving the problems in industry, such as lacking of variety of damping magnesium base alloy, selecting and using of rare-earth resource or drawback of substitution.

设计和制备中等刚度、中等强度、上中等阻尼性能和中等原料成本的二元增强阻尼镁基合金的方法，得到的该合金有利于平衡优化刚度、宽频段、宽的应变振幅、宽温度区间、强度、足够耐高温、抗蠕变、韧性、价格、利于防腐处理和利于热加工等实际应用中需求的要素，利于解决工业上可供选择的阻尼镁基合金品种不多以及稀土资源选择利用或替代利用性不足的问题。

An improved chemical method for the determination of the molar substitution degree of hydroxyethyl guar gum has been described.

本文用模型小分子一缩二乙二醇的醚键断裂实验证明了可行性，羟乙基瓜尔胶上的羟乙基链段与过量对甲苯磺酸-乙酸酐在130℃下反应14hr，醚键完全断裂生成酯，并在pH=11条件下煮沸1hr使酯完全水解，转变为乙二醇。

Cynanchum Lingtai apricot production in the average weight 65 grams, the brightly-colored fruit, juicy rich, sweet-sour taste, sweet from the nucleolus, when the late Qing Dynasty famous Shaanxi, Gansu provinces, the Qing imperial court Tongzhi tribute for years.

灵台生产的牛心杏平均单果重65克，果实色泽鲜艳，汁多味浓，甜酸适口，离核仁甜，清末时就驰名陕、甘两省，清同治年间曾为朝廷贡品。

Chenopodium album,Solanum nigrum, and Amaranthus retroflexus were very susceptible to the herbicides. Polygonum persicaria and Abutilon theophrasti were relatively less susceptible to the herbicides, and Lycopersicon esculentum was not susceptible to it. The relationship between reduction rates of weed biomass and PPM values of weed leaves 2,4, and 6 days after treatment was established.

供试的6种杂草对该混剂的敏感性存在显著差异：红心藜Chenopodium album、龙葵Solanum nigrum和反枝苋Amaranthus retroflexus对该混剂最敏感，ED90值分别为47.65、71.67和29.17g/hm2；春蓼Polygonum persicaria和苘麻Abutilon theophrasti敏感，ED90值分别为96.91、114.20g/hm2；而番茄不敏感。