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排序方式: 共有201条查询结果,搜索用时 15 毫秒
1.
加强p除环上自共轭矩阵的几个定理 总被引:6,自引:0,他引:6
本文将实对称矩阵和复Hermiitian环矩阵,以及更特殊的正定与半正定矩阵的一些较为深入的定理推广到加强p除上矩阵中来. 相似文献
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实验研究结果表明双核金属酞菁类化合物MPc-PcM(M=V、Cr、Mn、Fe、Co、Ni、Cu)是催化H_2S液相氧化反应的良好催化剂,且其催化活性顺序为Co>Ni>V>Fe>Cu>Cr>Mn.采用量子化学理论计算方法(INDO/S)分析了其前线分子轨道的构成特征,结果表明这几种MPc-PcM的LUMO轨道皆为有金属离子参与形成的π轨道,但HOMO轨道间的差异却很大.M=Co、Ni、Cu、Cr时,其HOMO为π轨道;而M=Fe、Mn时,其HOMO却为σ轨道.正是在前线分子轨道的轨道类型、共轭程度及金属轨道贡献三方面因素的协同作用下,才导致MPc-PcM的催化活性顺序并非按中心金属离子价电子层d电子数的递变而呈现出规律性的变化. 相似文献
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A simple but robust droplet-based microfluidic system was developed for dose–response enzyme inhibition assay by combining concentration gradient generation method with electrochemical detection method. A slotted-vials array and a tapered tip capillary were used for reagents introduction and concentration gradient generation, and a polydimethylsiloxane (PDMS) microfluidic chip integrated with microelectrodes was used for droplet generation and electrochemical detection. Effects of oil flow rate and surfactant on electrochemical sensing were investigated. This system was validated by measuring dose–response curves of three types of acetylcholinesterase (AChE) inhibitors, including carbamate pesticide, organophosphorus pesticide, and therapeutic drugs regulating Alzheimer's disease. Carbaryl, chlorpyrifos, and tacrine were used as model analytes, respectively, and their IC50 (half maximal inhibitory concentration) values were determined. A whole enzyme inhibition assay was completed in 6 min, and the total consumption of reagents was less than 5 μL. This microfluidic system is applicable to many biochemical reactions, such as drug screening and kinetic studies, as long as one of the reactants or products is electrochemically active. 相似文献
5.
Shukun Wei Xiaoyou Hu Lingyu Du Linlin Zhao Hongjuan Xue Chaolun Liu James J. Chou Jin Zhong Yimin Tong Shuqing Wang Bo OuYang 《Molecules (Basel, Switzerland)》2021,26(5)
Hepatitis C Virus (HCV) is the key cause of chronic and severe liver diseases. The recent direct-acting antiviral agents have shown the clinical success on HCV-related diseases, but the rapid HCV mutations of the virus highlight the sustaining necessity to develop new drugs. p7, the viroporin protein from HCV, has been sought after as a potential anti-HCV drug target. Several classes of compounds, such as amantadine and rimantadine have been testified for p7 inhibition. However, the efficacies of these compounds are not high. Here, we screened some novel p7 inhibitors with amantadine scaffold for the inhibitor development. The dissociation constant (Kd) of 42 ARD-series compounds were determined by nuclear magnetic resonance (NMR) titrations. The efficacies of the two best inhibitors, ARD87 and ARD112, were further confirmed using viral production assay. The binding mode analysis and binding stability for the strongest inhibitor were deciphered by molecular dynamics (MD) simulation. These ARD-series compounds together with 49 previously published compounds were further analyzed by molecular docking. Key pharmacophores were identified among the structure-similar compounds. Our studies suggest that different functional groups are highly correlated with the efficacy for inhibiting p7 of HCV, in which hydrophobic interactions are the dominant forces for the inhibition potency. Our findings provide guiding principles for designing higher affinity inhibitors of p7 as potential anti-HCV drug candidates. 相似文献
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具有生物活性的有机磷化合物的研究V.α—[(取代)芳氧基乙酰氧基]烷基膦酸 总被引:6,自引:1,他引:6
通过取代苯氧乙酰氯和α-羟基烷基膦酸酯的缩合反应合成了8种标题化合物,用元素分析,红外,核磁及质谱作了表征,测定了它们的除草活性和植物生长调节活性。 相似文献
8.
本文给出了一类退缩的拟线性椭圆型方程-Div「↓u|^p-2↓u+F(x,u)」=B(x,u,↓u)在W^1,p(Ω)中弱解的C^1,λloc(Ω)正则性,其中Ω为R^N中行一区域。 相似文献
9.
以闪光二号加速器为研究平台, 建立了微分环阵列和Rogowski线圈同时监测二极管电流的方法,监测了二极管绝缘体表面的滑闪现象。根据电流探头测量结果的差异,分析了绝缘体滑闪对电子束流参数的影响。二极管绝缘体出现滑闪,位置附近的微分环波形严重畸变,其它位置的微分环和Rogowski线圈测量结果基本一致。采用距离滑闪位置较远的微分环结果处理二极管束流参数,相对于不出现滑闪时的结果,束流强度和总能量没有明显的变化。绝缘体滑闪沿面局部放电,能量损失较小,尚未对电子束流造成较大影响。 相似文献
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