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11.
In search of environmentally benign insecticides with high activity, low toxicity and low residue, a series of novel anthranilic diamide derivatives containing N-pyridylpyrazole was designed and synthesized. All the compounds were characterized by 1H NMR spectroscopy and elemental analysis. The single crystal structure of compound 8j was determined by X-ray diffraction. The insecticidal activities of the new compounds were evaluated. The results show that some compounds exhibited moderate insecticidal activities against Lepidoptera pests. Among this series of compounds, compounds 8o and 8p showed 100% larvicidal activity against Mythimna separate Walker, Plutella xylostella Linnaeus and Laphygma exigua Hubner at a test concentration of 200 mg/kg, which is equal to the commercial chlorantraniliprole.  相似文献   
12.
TwoNovelCellDivisionTypePGRsLIZheng-ming,QIAOLi-xin,ZHAOZhong-renandLIUTian-lin(Elewcoto-OrganicChernistryinstitute,NankazUni...  相似文献   
13.
Rovral[3-(3,5-二氯苯基)-1-异丙氨基甲酰乙内酰脲]是一种优良的广谱杀菌剂和种子处理剂,由于3,5-二氯苯胺不易制备,本文采用其它取代苯胺作为起始原料,采用固态光气制备异氰酸酯,中间体未经分离,经缩合、关环“一锅法”反应,得到化合物Ⅰ,进一步反应得到Ⅱ、Ⅲ系列新化合物。  相似文献   
14.
The title compound, N-(4-methyl-6-oxo-1,6-dihydro-pyrimidin-2-yl)-N'-(2-tritluoromethyl-phenyl)-guanidine, was synthesized and its structure was confirmed by using IR, MS,^1H NMR, and elemental analysis. The single crystal structure of the title compound was determined by X-ray diffraction. The preliminary biological test showed that the synthesized compound has a weak herbicidal activity.  相似文献   
15.
<正>The melt electrospinning of PMMA was investigated.The averaged fiber diameter thus obtained was reduced from 34.0μm to 19.7μm by adding di-(2-ethylhexyl)phthalate to reduce viscosity of the molten PMMA,and it further lowered down to 4.0μm when a KCl/ice-water solution was used as collection media.A comparison study on the PMMA fibers made through melt electrospinning and done by solution electrospinning was made.It was found that solution electrospinning was capable of fabricating very thin fibers as small as to a nanometer size,but resulted in a much wider fiber diameter range than melt-electrospinning did.In general,within some extent an increase in applied voltage and amount of the additive or a decrease in collection distance can give rise to a decreased fiber diameter and improved mechanical performance for the PMMA fibers by melt electrospinning.It was also indicated that the mechanical properties of the PMMA fibers made through melt-electrospinning were superior to those by solution elctropspinning.  相似文献   
16.
Thirteen new ethyl 2-(N-substituted-arylsulfonamido)-2-oxoacetates(3a-3m), based on the structure of Ketol-acid reductoisomerase(KARI) inhibitor IpOHA, were designed and synthesized. Their structures were established on the basis of ^1H NMR, IR, MS, and elemental analyses. The bioassay result reveals that the structural changes from hydroxyl group on the N atom of IpOHA to arylsulfonyl groups does not enhance the inhibitory activity of the compounds to KARI in vitro. Compounds 3c, 3h, 3k, and 3m are more effective than IpOHA against the monocotyledonous bamygrass at 100 ug/mL in herbicidal tests.  相似文献   
17.
我们采用氧化锆双晶衬底制备了YBaCuO双晶结,测量了其电流电压特性,采用液氮制冷和小型脉冲管制冷机分别实现了毫米波谐波混频实验.通过实验结果的初步讨论和比较,我们对系统的微波耦合和噪声抑制提出了改进方案  相似文献   
18.
针对传统精馏塔系统和内部热耦合精馏塔系统两种不同的精馏系统,以苯―甲苯物系和丙烯―丙烷物系两种理想的二组分物系分别作为研究对象,以系统的热力学效率、公用工程费用和节能百分率作为研究评价基准,模拟并研究分析压缩比、进料热状态等参数对传统精馏塔和内部热耦合精馏塔节能效果的影响,两种不同的理想物系下内部热耦合精馏系统之间的差异,并分析内部热耦合精馏节能的影响因素,为内部热耦合精馏塔内部节能研究提供参考。  相似文献   
19.
Ten new N-oxalyl derivatives of neonicotinoid compound were designed and synthesized. Their structures were confirmed by 1H NMR spectra, elemental analysis and X-ray diffraction. The preliminary insecticidal activities of the new compounds were evaluated. The results of bioassays indicate that the title compounds exhibit moderate insecticidal activities. Surprisingly, the insecticidal activity of compound 7b against bean aphids at 200 mg/kg is 100%, which is comparable to that of the commercialized imidacloprid.  相似文献   
20.
The title compound, 5-N-I-propyl-2-(2′-nitrobenzenesulfonyl)-glutamine, was synthesized and its structure was confirmed by IR, MS, 1H NMR, and elemental analysis. The single crystal structure of the title compound was determined by X-ray diffraction. The crystal belongs to Monoclinic, space group P2(1), with α=0.69281(11) nm,b=0.76508(12),c=1.5843(3) nm,α=90°,β=90.941(3)°,γ=90°,V=0.8397(2) nm3,Z=2,Dc=1.477 g/cm3,μ=0.236 mm-1 , F(000)=392, R=0.0297, and wR=0.0664.  相似文献   
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