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1.
以三氟乙酰丙酮(tfac)为共配体的稀土配合物分别与5-溴-2-羟基苯取代的自由基配体和5-硝基-2-羟基苯取代的自由基配体进行反应,合成3个稀土-自由基配合物[Ln2(tfac)4(NIT-5Br-2PhO)2](Ln=Gd (1),Dy (2))和[Dy2(tfac)4(NIT-5NO2-2PhO)2](3)(NIT-5Br-2PhOH=2-(2′-hydroxy-5′-bromophenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide,NIT-5NO2-2PhOH=2-(2′-hydroxy-5′-nitrophenyl)-4,4,5,5-tetra-methylimidazoline-1-oxyl-3-oxide)。单晶结构分析表明这3个化合物中的稀土离子均通过自由基配体上的羟基氧基团连接为双核的结构。配合物1的直流磁化率表征揭示了Gd(Ⅲ)离子间的反铁磁耦合对其磁行为起主要作用。  相似文献   
2.
Leonurine (1), an important ingredient in leonurus sibiricus L., can be used for some gynecological disease. We have developed a concise and efficient synthetic route of Leonurine, which can be optimized for mass production. Commercially available compound 6 and 2,3-dihydrofuran (7) were used as starting materials. And the toxicity study on zebrafish shows that Leonurine would promote the hatching of zebrafish embryos at low concentration and result in acute death or chronic lethal toxicity at high concentration.  相似文献   
3.
In this paper, we extend one of Erdélyi's classical integrals for the Gauss hypergeometric functions to a special class of generalized hypergeometric functions in which certain pairs of numerator and denomiator parameters differ by positive integers. Our main results are achieved by applying the fractional integration by parts and series manipulation technique. Some special cases are also pointed out which includes a new extension of a Thomae-type transformation.  相似文献   
4.
以超强耐酸碱的表面活性剂-丁基封端脂肪醇聚氧乙烯醚作为晶型调节剂,利用钛酸丁酯和氢氧化钠的水热反应制备了单斜相与锐钛矿相双晶相TiO2/多壁碳纳米管(简称MWNTs)复合材料,并考察了复合材料的可见光光催化活性。结果显示:MWNTs的加入可调控TiO2的晶相组成,增强TiO2的光催化活性,其中含5%MWNTs的样品具有较高的催化降解效率;随煅烧温度的升高,样品的光催化活性大幅提升。其机理归因于(1)促进单斜相和锐钛矿相双晶相结构的形成;(2)碳纳米管优良的导电作用及碳纳米管/TiO2间的异质结效应;(3)高温下碳纳米管分解产生的碳元素掺杂作用。  相似文献   
5.
郝晓辰  姚宁  汝小月  刘伟静  辛敏洁 《物理学报》2015,64(14):140101-140101
针对无线传感器网络中节点因干扰过大导致重传能耗增加, 进而节点过早失效、网络生命期缩短的问题, 根据网络拓扑信息和路由信息设计节点的负载模型, 从而构建了节点的生命期模型. 然后利用博弈论将路径增益、交叉干扰和节点生命期等性能参数融入到效益函数中, 构建信道分配博弈模型. 理论分析证明该博弈模型存在纳什均衡. 进而运用最佳回应策略, 在所构建的信道分配博弈模型的基础上, 设计了一种优化网络生命期的抗干扰信道分配算法. 该算法使节点在选择信道时避免与网络中交叉干扰较大的节点和生命期较小的节点使用相同信道, 实现干扰小、能耗低且均衡的信道选择. 理论分析与仿真结果证明该算法最终能够快速地收敛到纳什均衡, 且具有较小的信息复杂度, 从而减小算法本身的通信能耗. 同时, 该算法具有良好的抗干扰性和信道均衡性, 能够有效地延长网络生命期.  相似文献   
6.
The title complex Salen Co(Ⅲ)Cl(Salen = 6,6’-((1E,1’E)-(cyclohexane-1,2-diylbis(azaneylylidene))bis(methaneylylidene))bis(2,4-di-tert-butylphenol)) was synthesized and characterized by elemental analysis, IR spectroscopy, 1H NMR and UV-Vis. The complex can be used as catalyst for the propylene oxide(PO)/CO2 copolymerization in different conditions of reaction time, reaction temperature, carbon dioxide pressure and monomer concentration, and the optimum conditions for copolymerization were obtained.  相似文献   
7.
Multi-component MOFs contain multiple sets of unique and hierarchical pores, with different functions for different applications, distributed in their inter-linked domains. Herein, we report the construction of a class of precisely aligned flexible-on-rigid hybrid-phase MOFs with a unique rods-on-octahedron morphology. We demonstrated that hybrid-phase MOFs can be constructed based on two prerequisites: the partially matched topology at the interface of the two frameworks, and the structural flexibility of MOFs with acs topology, which can compensate for the differences in lattice parameters. Furthermore, we achieved domain selective loading of multiple guest molecules into the hybrid-phase MOF, as observed by scanning transmission electron microscopy–energy-dispersive X-ray spectrometry elemental mapping. Most importantly, we successfully applied the constructed hybrid-phase MOF to develop a dual-drug delivery system with controllable loading ratio and release kinetics.  相似文献   
8.
Ionic liquid gel polymers have widely been used as the electrolytes in all-solid-state supercapacitors, but they suffer from low ionic conductivity and poor electrochemical performance. Arc discharge is a fast, low-cost and scalable method to prepare multi-layered graphene nanosheets, and as-made graphene nanosheets (denoted as ad-GNSs) with few defects, high electrical conductivity and high thermal stability should be favorable conductive additive materials. Here, a novel ionic liquid gel polymer electrolyte based on an ionic liquid (EM1MNTF2) and an copolymer (P(VDF-HFP)) was modified by the addition of ad-GNSs as an ionic conducting promoter. This modified gel electrolyte shows excellent thermal stability up to 400 ℃ and a wide electrochemical window of 3 V. An all-solid-state supercapacitor based on commercial activated carbon was fabricated using this modified ionic liquid gel polymer electrolyte, which shows obviously improved electrochemical behaviors compared with those of the corresponding all-solid-state supercapacitor using pure ionic liquid gel polymer electrolyte. Specially, smaller internal resistance, higher specific capacitance, better rate performance and cycling stability are achieved. These results indicate that the ionic liquid gel polymers modified by ad-GNSs would be promising and suitable gel electrolytes for high performance all-solid-state electrochemical devices.  相似文献   
9.
We consider that the Higgs triplet Yukawa coupling takes the Friedberg-Lee texture, and the Higgs doublet Yukawa coupling simply identifies with the diagonal Yutawa coupling of charged lepton in the context of left-right symmetric model. In this scenario, the phenomenology, including effective neutrino masses, mixings, and thermal flavor-dependent leptogenesis and lepton flavor violation decays are studied. We investigate the combined constrain of the parameters in this scenario and test its consistency with present data.  相似文献   
10.
王敏杰  潘炜 《中国物理快报》2008,25(11):3860-3863
We propose two schemes of quantum secure direct communication (QADC) combined ideas of user authentication [Phys. Rev. A 73 (2006) 042305] and direct communication with dense coding [Phys. Rev. A. 68 (2003) 042317]. In these protocols, the privacy of authentication keys and the properties of the EPR pairs not only ensure the realization of identity authentication but also further improve the security of communication, and no secret messages are leaked even if the messages were broken.  相似文献   
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