| 1. | Organophosphates are broad - spectrum contact insecticides with relatively higher toxicity and longer residual activities
有机磷是广谱触杀性除害剂，毒性相对高，效力较持久。 |
| 2. | Its activity became declining when the temperature was above 70 and when the temperature is 90 , its residual activity is 38 . 4 %
4 ，在ph7对时dna酶的活性急剧下降， ph90时剩余活性为1而出 |
| 3. | There are also some specially formulated pyrethroid products with extended residual activity that can be applied as residual sprays
有些配方的产品具有较持久残留作用，可用作残留喷洒的方法去施放。 |
| 4. | These chemicals are broad - spectrum contact insecticides that provide rapid knockdown effects on insects but with only little residual activity
这些化学品是广谱触杀性除害剂，具快速触杀作用，但残留效力并不持久。 |
| 5. | 5 and was virtually inactive above ph 6 . 0 . when the enzyme was incubated at various ph values at 37 ? c for 30 min in the absence of substrate and the residual activity was measured , the phytase was found to be stable at the ph range of 2 to 8
该酶反应的最适ph值为5 . 5 ，在phz一6之间都有较高的酶活性， ph大于6时植酸酶的活性迅速下降，在phz一8之间的稳定性很好，活性> 70 % 。 |
| 6. | There are many different formulated s - methropene products in the market ; some only have little residual activity and are intended to target at and control a single brood of mosquitoes while others are slow - release formulations offering an extended period of control which lasts from 30 up to 150 days . it is important to note that the chemical must be present in the water when the larvae are in the late developmental stage for it to be effective
市面有多种不同配方的s -烯虫酯产品，有些功效并不持久，只是用来防治当时已在该处的蚊子幼虫，而有些则有特别配方，可不断发挥功效，防治的时间长达30日，最长更可达150日。当幼虫在生长期的后期时，这种化学物必须存在水中，才能发挥最佳防治功效，这点必须留意。 |
