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The rhizosphere soil microorganism and rhizosphere soil enzyme activity werepositive correlated with each other.Except aerobic bacteria and actinomycetes andfungi did not achieve significant or extreme significant correlation with urease,theother factors all achieved significant or extreme significantcorrelation.Besides,through a correlation analysis between rhizosphere agrobiologyand rhizosphere soil nutrient,except rapidly available K was negative correlation with urease and catalase,the other agrobiology factors were positive correlation with soilnutrient, aerobic bacteria and sucrase and catalase were extreme significantcorrelation with alkaline hydrolytic N and organism matter and rapidly available P;actinomycetes was extreme significant correlation with all soil nutrient factors;fungiwas extreme significant correlation with alkaline hydrolytic N and organism matterand rapidly available P, significant correlation with rapidly available K;urease wasextreme significant correlation with alkaline hydrolytic N, significant correlation withrapidly available P.

本试验所测定的根系土壤微生物与根系土壤酶活性间均呈正相关，除了好、气性细菌、放线菌、真菌与脲酶间未达到显著或极显著相关外，其余因子间均呈显著或极显著相关；此外，通过根系土壤生物学因子与根系土壤养分相关分析，发现除了速效K与脲酶、过氧化氢酶呈负相关外，其余生物因子与土壤养分因子间均呈正相关，其中，好气性细菌、蔗糖酶、过氧化氢酶与水解N、有机质和速效P极显著相关；放线菌与所有养分因子间均极显著相关；真菌与水解N、有机质和速效P极显著相关，与速效K显著相关；脲酶与水解N极显著相关，与速效P显著相关。

The content of biuret by colorimetry and the total content of nitrogen in urea and biuret were mensurated.

摘 要：对固相法和液相法合成氰尿酸的方法进行比较，采用比色法测定缩二脲含量，用甲醛测定尿素、缩二脲的总氮量，由缩二脲的含量、总氮量推算出尿素的含量及产品的纯度，从而说明液相法的优势。

Target compounds have been synthesized by condensation of the aromatic nucleus and amino heterocylcle with acyl isocyanates or acylisothiocyanates in absolutely anhydrous and aprotic solvent.

为了寻找高活性的农药品种，利用生物等排原理和亚结构连接法，对脲类化合物的母体结构进行了修饰，将芳氧羧酸类及吡唑环引入酰基脲母体结构中，利用酰基异氰酸酯与杂芳环胺类化合物在无水非质子溶剂中发生亲核加成反应，合成了四个系列21种新的酰基脲类目标化合物。

In Chapter 6, an extensive kinetic study of the inhibition of ribonuclease A and papain by urea has been performed. The results suggest that the effect of urea on activities of these enzymes can be well described by the denaturant binding model. The binding constants of urea determined by the present method are nearly identical to that determined from a variety of different studies on model compounds and proteins.

我们在第六章中研究了脲作用下核糖核酸酶A和木瓜蛋白酶的抑制动力学，发现变性剂结合模型可以很好地描述脲对这两个酶活力的影响，而且用我们自己建立的方法测得的脲与蛋白质的结合常数与前人通过对模型化合物和某些蛋白质的研究所获得的数值基本一致。

On the basis of the kinetic equation of substrate reaction in the presence of urea or guanidine hydrochloride, all microscopic kinetic constants for the free enzyme and enzyme-substrate binary and ternary complexes have been determined. The results of the present studies indicate that:①In the presence of urea or guanidine hydrochloride, enzyme-substrate complexes lose their activity less rapidly than the free enzyme. Therefore, both substrates, NADPH and 7, 8-dihydrofolate, protect dihydrofolate reductase against inactivation.②The denaturation of dihydrofolate reductase by urea follows single-phase kinetics, and changes in enzyme activity and tertiary structure proceed simultaneously in the unfolding process, so it may be an"all or none"process.③The GdnHCl-induced unfolding of the dihydrofolate shows a biphasic transition, while the change in the enzyme activity is a single exponential process. The rate constant of inactivation is consistent with that of the fast conformational change. Therefore, the kinetic intermediate of protein unfolding should be a partially folded and inactive form.

我们根据在脲或盐酸胍存在下的底物反应动力学方程求得游离酶和酶底物二元、三元复合物的微观动力学常数，结果表明：①酶-底物二元、三元复合物的失活速度明显慢于游离酶，说明两个底物二氢叶酸和NADPH对酶的失活都具有一定程度的保护作用；②在脲作用下，酶的失活和构象变化均为单指数项过程，而且酶的活力丧失和三级结构变化是同时发生的，说明二氢叶酸还原酶的脲变性可能是一个"全或无"的两态过程；③在盐酸胍作用下，酶的构象变化为两相过程，而失活则是单指数项过程，酶分子构象变化的快相速度常数与失活速度常数基本一致，因此我们认为二氢叶酸还原酶的盐酸胍变性过程中存在一个没有活力、但仍具备一定空间结构的变性中间体。

The pyrethrin insecticides had lower toxicities to this insects, and the the corrected mortality of avermectin and the chitin synthesis inhibitors is lower than 40%, which's dose is 50 mg/kg.

微生物源杀虫剂阿维菌素和几丁质合成抑剂灭幼脲、杀铃脲和除虫脲对细胸金针虫幼虫的毒力较低，在剂量为50mg/kg土时，其校正死亡率均在40%以下。

Methods: Glipizide gliclazide glyburide glimepiride gliquidone repaglinide nateglinide pioglitazone rosiglitazone metformin phenformin and tolbutamide added in the blank ground samples were extracted with 80% methanol and were separated from an ACQUITY UPLC DBH C18 column with a gradient mobile phase of acetonitrile - 0.2 % formic acid water solution. A tandem quadrupole mass spectrometer equipped with electrospray ionization source was used in positive ion mode multiple reaction monitoring was performed to quantify above mentioned compounds.

被添加在中成药制剂及其包装物中的二甲双胍、苯乙双胍、罗格列酮、吡格列酮、格列吡嗫娶瑞格列奈、甲苯磺丁脲、格列齐特、格列苯脲、那格列奈、格列美脲、格列喹酮等西药成分用80%甲醇提取，以乙腈- 0.2%甲酸水溶液为流动相梯度洗脱，在ACQUITY UPLC DBH C18色谱柱上分离，串联四级杆质谱检测，MRM方式采集并定量。

The quality and inhibition efficiency of thiourea, allylthiourea and phenylthiourea self-assembled films were studied by electrochemical impedance spectroscopy and polarization curves, respectively.

利用电化学阻抗谱和极化曲线研究了硫脲、烯丙基硫脲、苯基硫脲在金属铜表面上的自组装膜的质量和缓蚀效率，并通过量子化学计算进一步研究了各种分子和金属铜的相互作用。

These coordination compounds mostly have group ⅡB metals as center ions. The complexes are classified with ligand as three types: thiourea type, allylthiourea type and thiosemicarbazone type.

这类配合物大都以ⅡB族金属为中心离子，根据配体不同可分为硫脲类、烯丙基硫脲类及缩胺基硫脲类3种类型。

The results of biological tests indicated that, at 25 g/mL, 1-(4-bromo-3-ethyl-1-methyl-pyrazol-5'-ylcarbonyl-4-(2-nitrophenyl) semicarbazide (4d) showed inhibitory activities (52.6%) against Pyricularia oryzae. 1-(4-bromo-3-ethyl-1-methyl-pyrazol-5'-ylcarbonyl)-4-(3-chlorophenyl) semicarbazide (4j), 1-(4-bromo-3-ethyl-1-methyl-pyrazol-5'-ylcarbonyl)-4-(2,4-dimethylphenyl) semicarbazide (4k), 1-(4-bromo-3-ethyl-1-methyl-pyrazol-5'-ylcarbonyl)-4-(3,4-dimethyiphenyl) semicarbazide (41) and 1-(4-bromo-3-ethy-1-methyl-pyrazo1-5'-ylcarbonyl)-4-(2,4-difluorophenyl) semicarbazide (4m) showed inhibitory activities (45.6%) against Pyricularia oryzae, repestively.

初步生物活性实验结果表明，在25μg/mL浓度下，1-（1-甲基－3-乙基－4-溴－5-吡唑甲酰基）－4-（2-硝基苯基）氨基脲(4d)对水稻稻瘟病菌Pyricularia oryzae抑制活性达到52.6%；1-1-甲基－3-乙基－4-溴－5-吡唑甲酰基）－4-（3-氯苯基）氨基脲(4j，1-（1-甲基－3-乙基－4-溴－5-吡唑甲酰基）－4-（2，4-二甲基苯基）氨基脲(4k)，1-（1-甲基－3-乙基－4-溴－5-比唑甲酰基）－4-（3，4-二甲基苯基）氨基脲(41)和1-（1-甲基－3-乙基－4-溴－5-吡唑甲酰基）－4-（2，4-二氟苯基）氨基服(4m)对水稻稻瘟病菌Pyricularia oryzae抑制活性达到45.6%。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。