三苯基锡-2-(1,2-亚乙二硫)亚甲基-3-羰基-5-芳基-4-戊烯酸酯的合成及晶体结构

由2-(1,2-亚乙二硫)亚甲基-3-羰基-5-芳基-4-戊烯酸与三苯基氢氧化锡反应,合成了九个标题化合物3.用X射线衍射法测定了3b的晶体结构.该晶体属三斜晶系,空间群Pl,α=0.9074(2)nm,b=1.6809(3)nm,c=2.1834(4)nm,α=77.57(3)°,β=88.04(3)°,γ=89.47(3)°,V=3.2503nm~3,Z=2;R=0.0592.由锡氧原子间距离可推测,该晶体中羧酸根作为双齿配体与锡原子形成了分子内五配位结构.

Electrochemical impedance spectroscopy analysis for oxygen reduction reaction in 3.5% NaCl solution

The electrochemical impedance spectroscopy (EIS) at different potentials has been used to study the oxygen reduction reaction (ORR) in 3.5% NaCl solution on glassy carbon (GC) electrode in this work. Results show that ORR consists of three two-electron reaction steps and both superoxide ion (O-2(-)) and hydrogen peroxide (H2O2), which are produced by ORR, obstruct the diffusion of oxygen to the surface of the electrode and make the EIS results change into a transmissive finite diffusion process with the real part contraction and a reflective finite diffusion process from a semi-infinite diffusion process. The values of electron transfer resistance (R-t) and diffusion resistance (R-d) were calculated from EIS. O-2(-) influenced strongly on the Rt values and induced a maximum at -0.45 V.

Comparative Study Of The Influence Of Natural Convection On Directional Solidification Of Al-3.5 Wt% Ni And Al-7 Wt% Si Alloys

We present numerical simulations of thermosolutal convection for directional solidification of Al-3.5 wt% Ni and Al-7 wt% Si. Numerical results predict that fragmentation of dendrite arms resulting from dissolution could be favored in Al-7 wt% Si, but not in Al-3.5 wt% Ni. Corresponding experiments are in qualitative agreement with the numerical predictions. Distinguishing the two fragmentation mechanisms, namely dissolution and remelting, is critical during experiments on earth, when fluid flow is dominant. (C) 2007 COSPAR. Published by Elsevier Ltd. All rights reserved.

Laser action from 1,3,5,7-tetramethyl-2,6-diethyl-8-n-propyl pyrromethene-BF2

We measured spectroscopic and laser action properties of a novel 8-position substituted pyrromethene-BF2, namely 1,3,5,7-tetramethyl-2,6-diethyl-8-n-propyl pyrromethene-BF2 complex. The laser action was performed with the corresponding dye solution in ethanol, which was placed in a Littman-type laser cavity pumped by the second harmonic of a Q-switched Nd:YAG laser. The spectroscopic measurements clearly indicated that the corresponding dye solution in ethanol exhibited intense absorption in the visible spectral region with large fluorescence quantum yield. It possesses rather low triplet-triplet absorption in the spectral region 460-550 nm and almost negligible triplet-triplet absorption in the lasing spectral region. As a consequence, it lases nearly as efficiently as commercially available benchmark laser dyes such as Rhodamine-6G and outperformed them in wavelength tunability in our laser cavity and pump geometry. (C) 2002 Optical Society of America.

Nd：Y3Sc（1．5）Al（3．5）O（12）透明陶瓷的光谱性能以及激光输出

采用燃烧法制备了Nd：YSAG粉体,经过成型、素烧,最终在氢气气氛中烧结制备了Nd：YSAG透明陶瓷.测试结果表明,Nd：YSAG透明陶瓷具有荧光谱线较宽,荧光寿命较长的特点.激光实验得到的激光输出,斜率效率为23.6%,输出功率为0.36W,输出激光的谱线分布较宽.

Dual-wavelength competitive output in Nd:Y3Sc1.5Al3.5O12 ceramic disk laser

In this paper, we demonstrated a dual-wavelength competitive output in Nd:Y3SC1.5Al3.5O12 ceramic disk laser. Different dual-wavelength output behaviors for Nd:YSAG and Nd:YAG ceramic disk laser were investigated and discussed. By applying the energy transfer model, we suggested the reasonable explanation for this new phenomenon as the disordered replacing of Al3+ ions by Sc3+ ions. The main advantage of the dual-wavelength ceramic laser is the possibility to serve as the seed source to generate Terahertz radiation. (C) 2008 Elsevier B.V. All rights reserved.

2,4-二取代氨基-6-取代-[1,3,5]三嗪或1,3-嘧啶类化合物、其制备方法、药物组合物及用途

一种新型的2，4-二取代氨基-6-取代-[1，3，5]三嗪或1，3-嘧啶衍生物及其制备方法、药物组合物和其药理用途，其结构通式如式(I)所示，其中R1、R2、R3、R4、R5、R6、A、B、X、Y和Z的定义如说明书中所述。该类化合物与HIV-1整合酶具有很高结合活性，并且在底物竞争测试中能够有效的抑制整合酶对底物的结合。因此该类化合物是较强的HIV-1整合酶抑制剂，有望开发成为新的抗HIV病毒药物。

Establishment and characterization of dual-species biofilms formed between a 3,5-dinitrobenzoic-degrading strain and bacteria with high biofilm-forming capabilities

In this study, the possibility of establishing a dual-species biofilm from a bacterium with a high biofilm-forming capability and a 3,5-dinitrobenzoic acid (3,5-DNBA)-degrading bacterium, Comamonas testosteroni A3, was investigated. Our results showed that the combinations of strain A3 with each of five strains with a high biofilm-forming capability (Pseudomonas sp. M8, Pseudomonas putida M9, Bacillus cereus M19, Pseudomonas plecoglossicida M21 and Aeromonas hydrophila M22) presented different levels of enhancement regarding biofilm-forming capability. Among these culture combinations, the 24-h dual-species biofilms established by C. testosteroni A3 with P. putida M9 and A. hydrophila M22 showed the strongest resistance to 3,5-DNBA shock loading, as demonstrated by six successive replacements with DMM2 synthetic wastewater. The degradation rates of 3,5-DNBA by these two culture combinations reached 63.3-91.6% and 70.7-89.4%, respectively, within 6 h of every replacement. Using the gfp-tagged strain M22 and confocal laser scanning microscopy, the immobilization of A3 cells in the dual-species biofilm was confirmed. We thus demonstrated that, during wastewater treatment processes, it is possible to immobilize degrader bacteria with bacteria with a high biofilm-forming capability and to enable them to develop into the mixed microbial flora. This may be a simple and economical method that represents a novel strategy for effective bioaugmentation.

6-(1H-吲哚-3-甲基)-5-乙基-3H-嘧啶-4-酮类化合物的合成及抗HIV活性研究

基于二氢烷氧苄基嘧啶酮(DABO)类非核苷类逆转录酶抑制剂(NNRTIs)的构效关系研究,设计合成了2个新的6-(1H-吲哚-3-甲基)-5-乙基-3H-嘧啶-4-酮类化合物,并采用C8166细胞进行了体外抗HIV活性测试,为新型S-DABO类非核苷类逆转录酶抑制剂结构修饰提出了新的设想.

Long period grating for 3-5 mu m quantum-well infra-red photodetectors

By considering all possible high order diffracted waves, the authors calculate the coupling efficiency of long period gratings for 3-5 mu m quantum-well infra-red photodetectors (QWIPs) on the basis of the modal expansion model (MEM). A large coupling efficiency for 3-5 mu m QWIPs has been demonstrated. This greatly reduces the difficulties in fabricating 3-5 mu m grating coupled QWIPs and opens the way to fabricate high performance 3-5 mu m and two colour QWIPs image arrays.

3～5.3μmIn_xGa_(1-x)As/Al_yGa_(1-y)As/Al_zGa_(1-z)As非对称台阶量子阱红外探测器

于2010-11-23批量导入

3~5微米双势垒量子阱红外探测器结构在不同偏压下的光伏响应

于2010-11-23批量导入