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21.
A novel class of (5-(pent-1-enyl)thiophen-2-yl)pyrazole antagonists was discovered, many of which exhibited potent CB1 activity and good CB1/2 selectivity, suggesting that along with a 1,3-transposition of the carbonyl of the pyrazole 3-carboxamide, bioisosteric replacement of the conventional pyrazole 5-aryl group with a thienyl ring substituted with an appropriate alkenyl moiety is viable.  相似文献   
22.
The absorbance spectra of thin-film solar cells (TFSCs) can be enhanced by constructing the tunable periodic Ag-shell nano-bead (PASNB) arrays in the active material. In this paper, we investigated a plasmonic thin-film solar cell (TFSC) which composed of the arrays of PASNB deposited onto a crystalline silicon layer. By performing three-dimensional finite element method, we demonstrate that near field coupling among the PASNB arrays results in SPR modes with enhanced absorbance and field intensity. The proposed structure can significantly enhance the plasmonic activity in a wide range of incident light and enlarge working wavelength of absorbance in the range of near-UV, visible and near-infrared. We show that the sensitivity of the PASNB arrays reveals a linear relationship with the thickness of Ag-shell nano-bead (ASNB) for both the anti-bonding and bonding modes in the absorbance spectra. The broadband of absorbance spectra could be expanded as a wide range by varying the thickness of ASNB while the particle size is kept constant. Simulation results suggest this alternative scheme to the design and improvements on plasmonic enhanced TFSCs can be extended to other nanophotonic applications.  相似文献   
23.
This current study aimed to enhance the thermal conductivity of thin film composites without compromising other polymer qualities. The effect of adding high thermal conductivity nanoparticles on the thermal properties and moisture absorption of thin film epoxy composites was investigated. Three types of fillers in nanosize with high thermal conductivity properties, boron nitride (BN), synthetic diamond (SD), and silicon nitride (Si3N4) were studied. SN was later used as an abbreviation for Si3N4. The contents of fillers varied between 0 and 2 vol.%. An epoxy nanocomposite solution filled with high thermal conductivity fillers was spun at 1500–2000 rpm to produce thin film 40–60 µm thick. The effects of the fillers on thermal properties and moisture absorption were studied. The addition of 2 vol.% SD produced the largest improvement with 78% increment in thermal conductivity compared with the unfilled epoxy. SD‐filled epoxy thin film also showed good thermal stability with the lowest coefficients of thermal expansion, 19 and 124 ppm, before and after Tg, respectively, which are much lower compared with SN‐filled and BN‐filled epoxy thin film composites. However the SD‐filled epoxy film has its drawback as it absorbs more moisture compared with BN‐filled and SN‐filled epoxy film. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
24.
Using the Seiberg-Witten map, we obtain a quantum electrodynamics on a noncommutative space, which has arbitrary charge and keep the gauge invariance to at the leading order in theta. The one-loop divergence and Compton scattering are reinvestigated. The noncommutative effects are larger than those in ordinary noncommutative quantum electrodynamics.  相似文献   
25.
反相微乳液法合成碘化铅纳米棒   总被引:1,自引:0,他引:1  
用Pb(NO3)2和KI为反应物, 在水溶液/Triton X-100/正己醇/环己烷反相微乳液体系中制得了碘化铅纳米棒. 研究了ω0(水与表面活性剂的摩尔比)、反应物浓度、反应温度及陈化时间等因素对产物尺寸和形貌的影响, 并用TEM和XRD等技术对产品进行了表征.  相似文献   
26.
A new polyoxygenated briarane-type diterpenoid, briarenol A (1), has been isolated from a gorgonian coral belonging to the genus Briareum. The structure, including the relative stereochemistry of briarane 1, was elucidated by the interpretation of spectral data. The configuration of 1 was further supported by molecular mechanics calculations.  相似文献   
27.
对100个神经氨酸酶抑制剂抗禽流感药物结构并与其活性建立定量构效关系模型。采用本实验室提出的三维全息原子场作用矢量(3D-HoVAIF)对100个神经氨酸酶抑制剂进行结构表征,然后采用逐步回归对变量进行筛选后,运用偏最小二乘建立3D-HoVAIF描述子与神经氨酸酶抑制剂活性之间的QSAR模型。结果表明:复相关系数(R),交互校验的复相关系数(Q2)和模型的标准偏差(SD)分别为R2=0.805、Q2=0.657和SD=0.936,模型具有良好的稳定性和预测能力,并对文献中23个药物和设计的32个化合物进行了预测。表明三维全息原子场作用矢量能较好表征该类分子结构信息值得进一步推广应用。  相似文献   
28.
The aim of this work was to determine the effect of formulation of alginate beads on their mechani-cal behavior and stiffness when compressed at high speed. The alginate beads were formulated using different types and concentrations of alginate and gelling cations and were produced using an extrusion-dripping method. Single wet beads were compressed at a speed of 40 mm/min,and their elastic limits were investigated,and the corresponding force versus displacement data were obtained. The Young's moduli of the...  相似文献   
29.
Garnet-type electrolytes suffer from unstable chemistry against air exposure, which generates contaminants on electrolyte surface and accounts for poor interfacial contact with the Li metal. Thermal treatment of the garnet at >700 °C could remove the surface contaminants, yet it regenerates the contaminants in the air, and aggravates the Li dendrite issue as more electron-conducting defective sites are exposed. In a departure from the removal approach, here we report a new surface chemistry that converts the contaminants into a fluorinated interface at moderate temperature <180 °C. The modified interface shows a high electron tunneling barrier and a low energy barrier for Li+ surface diffusion, so that it enables dendrite-proof Li plating/stripping at a high critical current density of 1.4 mA cm−2. Moreover, the modified interface exhibits high chemical and electrochemical stability against air exposure, which prevents regeneration of contaminants and keeps high critical current density of 1.1 mA cm−2. The new chemistry presents a practical solution for realization of high-energy solid-state Li metal batteries.  相似文献   
30.
建立细菌外源性表达的有活性的全长hPPARγ重组蛋白的纯化方法.利用pReceiver-B13-SUMO-PPARγ表达质粒转化至E.coli BL21 (DE3)细胞中诱导表达获得的全长hPPARγ重组蛋白;采用阴离子交换色谱法纯化目标蛋白;采用分子排阻色谱-高效液相色谱法(SEC-HPLC)法测定全长hPPARγ重组蛋白与Ros (Rosiglitazone,罗格列酮)配体的结合活性.经DEAE-52阴离子交换树脂一次纯化,从每升LB培养介质中可获得135mg、纯度为80%目标蛋白;该蛋白与罗格列酮的解离常数Kd为492nmol/L.本文所建立的方法能纯化出大量有活性、纯度较高的全长hPPARγ重组蛋白.  相似文献   
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