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201.
Application of Improved (G'/G)–Expansion Method to Traveling Wave Solutions of Two Nonlinear Evolution Equations
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Xiaohua Liu Weiguo Zhang & Zhengming Li 《advances in applied mathematics and mechanics.》2012,4(1):122-130
In this work, the improved (G'/G)-expansion
method is proposed for constructing more general exact
solutions of nonlinear evolution equation with the aid of symbolic
computation. In order to illustrate the validity of the method we
choose the RLW equation and SRLW equation. As a result, many new and
more general exact solutions have been obtained for the equations. We
will compare our solutions with those gained by the other authors. 相似文献
202.
203.
Sha Zhou Xiangde Meng Ruyi Jin Yi Ma Yongtao Xie Yu Zhao Hongjian Song Lixia Xiong Zhengming Li 《Molecular diversity》2017,21(4):915-923
To investigate the “methyl” impact on bioactivity of sulfiliminyl dicarboxamides, a total of 16 novel N-cyano and N-trifluoroacetyl sulfiliminyl dicarboxamides containing m-heptafluoroisopropylated aromatic amino moiety were studied. Two series of sulfiliminyl substituents were designed, synthesized and evaluated against oriental armyworm (Pseudaletia separata Walker) for their insecticidal activities. Their chemical structures were established by corresponding \(^{1}\hbox {H}\) NMR, HRMS and optical polarimetry. Bioassay results revealed that some of the title compounds showed potent insecticidal activities against oriental armyworm. Notably, compounds IIa, IIIa, IVa exhibited 100% activity at \(1\, \hbox {mg}\,\hbox {L}^{-1}\), in particular, IIa showed a comparable control efficacy to that of the commercial product flubendiamide. The SAR of these N-cyano sulfiliminyl isomers can be summarized as follows (Sc, Ss) \(\ge \) (Sc, Rs), while the N-trifluoroacetyl sulfiliminyl isomers is (Sc, Rs) \(\ge \) (Sc, Ss). Comparative molecular field analysis indicated that an electropositive substituent, \(\hbox {CH}_{3}\) group in the benzene ring was very important for the improvement in biological activity. These results could hold promise for novel chiral sulfiliminyl RyR regulators. 相似文献
204.
Two series of novel anthranilic diamides containing oxime ester and diacylhydrazine moieties were designed and synthesized.Their structures were characterized by melting points,1H NMR,13C NMR and high resolution mass spectrometry(HRMS).The single crystal structure of compound 7e was determined by X-ray diffraction and their evaluated insecticidal activity against oriental armyworm(Mythimna separata) indicates that some of the compounds exhibited moderate insecticidal activities.Among the 20 compounds,6a and 6b show 100% larvicidal activity against Mythimna separate Walker at the test concentration of 100 mg/L. 相似文献
205.
CHEN Youwei WANG Baolei GUO Yanjun ZHOU Yunyun PAN Li XIONG Lixia YU Shujing LI Zhengming 《高等学校化学研究》2014,30(1):98-102
Caffeine is one of methyl xanthine compounds,which has the similar mode of action as ryanodine receptor insecticide.In order to find novel and efficient insecticide,structural modification of certain methyl xanthine compounds was made by introducing some common pesticidal active moieties into the structure of caffeine.Eleven novel methyl xanthine compounds were synthesized and characterized by 1H nuclear magnetic resonance(1H NMR),elemental analylsis or high-resolution mass spectrometry(HRMS).According to the biological activity results,it was found that these new compounds show moderate activity towards Mythimna separata Walker and Culex pipiens pallens.For example,compound 2d shows a lethality rate of 40% at 200 mg/L towards Mythimna separata Walker,compounds 2i and 2f show 56.7% and 53.3% lethality rates at 2 mg/L towards Culex pipiens pallens,which are all better than caffeine.In addition,some compounds of them show moderate antifungal activity to some plant pathogenous fungi. 相似文献
206.
将苯基引入到嘧啶环的4位, 设计、 合成了2个系列共24个结构新颖的磺酰脲类衍生物, 并对其生物活性进行了研究. 抑菌实验结果表明, 目标化合物对苹果轮纹病菌和小麦纹枯病菌表现出优异的抑制率, 其中化合物9f对5种病菌的抑制率均超过65%. 进一步研究发现, 化合物9f对苹果轮纹病菌的EC50值为8.63 mg/L, 略高于对照药百菌清(7.33 mg/L); 化合物8k和9k对小麦纹枯病菌的EC50值分别为5.48和6.09 mg/L, 与百菌清(4.26 mg/L)接近. 同时, 盆栽法除草测试结果表明, 在75 g/ha剂量下, 化合物8d和9d对油菜具有较好的芽前除草活性, 分别为86%和73%; 化合物9h对反枝苋的土壤处理抑制活性为100%, 优于对照药氯磺隆(96%). 相似文献
207.
通过1-甲硫基亚乙基氨-甲基氨基甲酸酯与二氯亚砜反应,制得一系列新的含硅氨基甲酸酯衍生物.化合物结构经1 ̄HNMR、元素分析IR和MS确证,测定了化合物3a的晶体结构.生物测定结果表明,该类化合物对蚊子、粘虫、玉米螟等多种害虫具有优良的杀虫活性,且与母体灭多威相比,在哺乳动物安全性方面有显著提高. 相似文献
208.
We study the quasitriangular structures ofT-smash product Hopf algebrasB
⋈
H which are constructed by Caenepeel, Ion, Militaru and Zhu. The necessary and sufficient conditions for a class ofT-smash product Hopf algebras to be quasitriangular Hopf algebras are given. As applications of our results, some corollaries
and examples are given as well.
This work was partially supported by the NSF grant of Henan Province, P. R. China. 相似文献
209.
通过解析计算研究了电磁脉冲在迎面而来的电离波阵反射后出现的频率上移、脉宽压缩及能量放大,并对实现上述目标最为有利的工作条件进行了讨论. 相似文献
210.
To discover novel strobilurins analogues with good and broad spectrum activity, a series of novel 3,4-dihydro-2H-1,2,4-benzothiadiazine 1,1-dioxides-based strobilurins was designed, synthesized, and tested against various phytopathogenic fungi. Compounds 7b, 7c, and 7k exhibited substantial and broad spectrum antifungal activities against the tested phytopathogenic fungi, especially compound 7b, which showed 100%, 80%, 90%, and 90% antifungal activity(in virto) against Erysiphe graminis(E. graminis), Puccinia sorghi Schw.(P. sorghi Schw.), Colletotrichum lagenarium(C. lagenarium), and Pseudoperonospora cubensis(P. cubensis) at 300 μg/mL, respectively, better or comparable to the positive control azoxystrobin. Moreover, compound 7b exhibited 85% greenhouse inhibition activity(in vivo) against E. graminis even at 0.2 μg/mL, equal to azoxystrobin(90%) and trifloxystrobin(90%). Meanwhile, compound 7b against P. cubensis displayed 70% and 55% greenhouse inhibition activity(in vivo) at 1.56 and 0.2 μg/mL, respectively, much better than those of azoxystrobin and trifloxystrobin(both 0% at 1.56 and 0.2 μg/mL). Therefore, compound 7b could be considered as the most promising fungicidal candidate for further study. Furthermore, based on the effective concentration(EC50) against C. arachidicola, the built CoMSIA model provided the useful reference for the further structural optimization design. 相似文献