半衰期

Therefore, the objectives of the study were to test degradation rates of four veterinary antibiotics, oxytetracycline, chloroteracycline, enrofloxacin and sulfamethazine, under different soil environments.

本文通过室内培养试验，应用降解速率常数和半衰期等参数评估了土霉素、金霉素、恩诺沙星和磺胺二甲嘧啶等4种代表性抗生素在5种土壤中避光、自然与灭菌等条件下的降解速率。

Human tissue-type plasminogen activator is a medicine used in thrombolytic treatment efficiently. Its application was limited by its defects, such as short half life and leading to blood in skull.

人组织型纤溶酶原激活剂是一种高效特异的溶血栓药物，但天然的t-PA存在半衰期短，有潜在的引起颅内出血的危险等缺点，因而限制了它的广泛应用。

Changed fast by a society and shortened knowledge half-life in the 21st century, in the face of such a society , make us to have to change one's own study way－individual learning turned to team learning.

二十一世纪是一个社会快速变迁，知识半衰期缩短的一个世纪，面对这样的社会，迫使我们不得不改变自己的学习方式－由个人学习转向团队学习。

Generally speaking, has used in the nuclear fuel certain transuranic elements for example the time for tens of thousands of years, must with the biological food chain isolation, be able to avoid for a long time to the humanity causing the damage!!!!

一般来说，使用过核燃料中某些超铀元素的半衰期长达数万年，必须长期与生物的食物链隔离，才能避免对人类造成伤害。问题补充：如果是用软件翻过来的话，请务必把语法错误改过来！

A short - lived , radioactive synthetic transuranic element produced from californium and having

铹一种寿命期短的、人工合成的放射性超铀元素，从锎中生成，有质量从255到260的同位素，半衰期从几秒钟到三分钟；原子序数

Pyrethroid ; Initial pollution degree ; Vegetable ; Half life ; Pollution index

拟除虫菊酯；农药起始污染程度；蔬菜；半衰期；污染指数

The half life of xanthene derivatives in water is between 5 hours to 7 hours, and on the surface of silica TLC plates is between 1 hour to 2 hours.

呫吨类化合物的光降解规律为：在水溶液中的光降解是假一级动力学化学反应，半衰期在5小时到7小时之间，属于同一个数量级。

The experimental results showed that the aquation of JM216 follows the pseudo-first-order- rate law, of which the observed-rate constant kobs is 5.0×1.0-6min-1and the half life period t1/2 is 96.25 days at 37℃.

结果表明，JM216的水合反应为准一级反应，反应对JM216为一级，37°C时水合反应表观速率常数为kobs=5.0×10-6min-1，半衰期t1/2＝96.25天。

Pneumoniae FH strain was cloned and the sequence was analysed by M13 DNA sequencing method. Comparing the PCR product sequcence with MP M-129 strain P1 gene, we found that there are 4 bases different. This may result from the different MP DNA templates. The maximum homology is 98.8%. The result confirmed the fidelity and specificity of the amplified target DNA segment by PCP, and suggested that two categories of MP P1 gene still exist a few differences even in the conservation region. The cloning MP DNA segment was labelled by random hexanucleotide priming, after hybridization, the probe detection was completed using an anti-digoxigenin antibody alkaline phosphatase conjugate, and the substrates 5-bromo-4-chloro-3-indolyl phosphate and nitro blue tetrazolium. This hybridization system is much superior to the radioactive probe hybridization, because it is safe, easy to handle and has no limitation of decay time. The time required for colormetic detection is also much less than the corresponding autoradiographic exposure time needed to achieve similar detection limits with 32P-labelled probes. The Dig-probes could be used repeatedly, and this made them not only much convenient to use, but also lower the cost, and worthwhile to be used popularly.

将PCR产物进行重组，并将阳性重组质粒，应用M13测序系统对产物进行DNA序列分析，并与MPM-129株P1基因核苷酸进行同源性比较，发现有4个位置的碱基发生了变化，其同源性为98.8％，证实了PCR所扩增DNA片段的准确性和特异性，同时也证实了不同MP组型的P1基因即使在保守区也存在着一定的差异，将克隆的目的DNA片段用异羟基洋地黄毒苷配基用随机引物法标记制备MP DNA探针，杂交后用碱性磷酸酶标记的抗Dig多克隆抗体与杂交体反应，再用BCIP和NBT呈色，制备MP DNA探针，鉴定所扩增片段的特异性，与同位素探针比较，Dig探针不受半衰期限制，可反复使用，而且价格低廉，值得推广使用。

The half-life of 35S-methamidophos on the Azolla, water,fish and straw are 1.5, 2.8, 6.2 and 2.2 days respectively.

35S-甲胺磷在模拟共生体系中按指数回归消失，它在萍、水、鱼和稻草上的半衰期分别为1.25、2.8、6.2和2.2天。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。