阿尔金山盐湖极端嗜盐古生菌的分离及16S rDNA序列分析

为了研究分析新疆阿尔金山国家自然保护区阿牙克库木湖嗜盐古生菌物种资源,对分离纯化到的极端嗜盐古生菌AJ2和AJ4,采用PCR方法扩增出其16S rRNA基因(16S rDNA),并测定了基因的核苷酸序列.基于16Sr DNA序列的同源性比较和系统发育学分析,发现菌株AJ2是Natrmema属中一个与其他成员不同的新种,命名为Natrinema ajinwuensis sp.nov.;菌株AJ4是Haloarcula属中成员argentinensis的一个亚种,取名为Haloar-cula argentinensis subsp.ajinwuensis.菌株AJ2和AJ4的16S rDNA序列已被GenBank数据库收录,其序列号分别为AY208972和AY208973.     

C1 C60F16O: A Fluorofullerene Ether Having Exceptionally Long Chromatographic Retention

From the product of fluorination of [60]fullerene with K₂PtF₆ at 470 °C, we have isolated a small quantity (ca. 0.5 mg) of C₆₀F₁₆O, an oxahomofluorofullerene (ether) of exceptionally long HPLC retention time (50% greater than any other known fluorofullerene). The ¹⁹F NMR spectrum consists of 16 main lines and 8 minor ones, due to C₆₀F₁₆O (a single isomer of C₁ symmetry) and C₆₀F₁₆, respectively. The presence of the latter (absent on initial isolation) indicates this ether to be relatively unstable, confirmed by the failure to obtain an EI mass spectrum. The empirical formula was therefore determined by MALDI-TOF mass spectrometry in the negative-ion mode, the laser fluence being carefully adjusted at the threshold of ion formation, whence the only observable signal corresponded to the molecular ion of C₆₀F₁₆O. At slightly higher laser fluence, the base peak of C₆₀F₁₆O^·- is accompanied by C₆₀F₁₆^·- and C₆₀F₁₅O^·-. Two closely similar structures (of similar calculated stabilities) are fully consistent with the NMR data. Calculated dipole moments and the exceptionally long retention HPLC retention times suggest that both C₆₀F₁₆ and C₆₀F₁₆O may be dimers.     

汽车安全辅助驾驶系统中通用测量控制模板的设计

汽车安全辅助驾驶在当前的研究领域是一个热点问题。该文介绍了研发的汽车安全辅助驾驶系统中通用测量控制模板的各部分组成和设计方法。     

Asymmetric synthesis of 3β-acetoxy-17,17-ethylendioxy-15β, 16β-methylene-5-androsten-7β-ol

3β-acetoxy-17, 17-ethylendioxy-15β, 16β-methylene-5-androsten-7β-ol(I) was prepared by 3 steps from 3β-acetoxy-15β, 16β-methylene-5-androsten-17-one (II) with overall yield of 52.7%. Thus, interaction of ethylene glycol and material (II) gave 3β-acetoxy- 17, 17-ethylendioxy-15β, 16β-methylene-5-androsten (III) which was subsequently oxidated and stereoselectively reduced to produce compound(I). The normal influencing factors, such as the types of oxidants and reductives, the mole ratio of reactants, the reaction temperature, and the addition ways of reactants, in oxidation and reduction were discussed. The results show that the oxidation rate order is CrO₃-C₅H₅N (1:1, mole fraction)>CrO₃-C₅H₅N(1:2)>(C₅H₅NH)₂Cr₂O₇ in terms of the oxidant, the yield of the oxidation becomes higher with increasing the oxidant stoichiometry and raising the reaction temperature. And the optimum condition is that the reaction temperature is at 30 °C, and n(III)/n(CrO₃-C₅H₅N(1:2))=1:20. The yield of the −7β alcohol order with Li[Al(OC(CH₃)₃)₃H] (e. g. 78.6%) is more than that with NaBH₄ (e. g. 14.5%) in terms of the reductive agent and the reduction rate decreases in the course of reaction. The compound (I) is characterized by IR and MS. Foundation item: Project (1357) supported by the Excellent Young Teachers Program of the Ministry of Education of China     

Novel Mapping Design Criterion for BICM-ID with Square QAM Constellations

Mapping design criteria of bit-interleaved coded modulation with iterative decoding (BICM-ID) with square 16QAM are analyzed. Three of the existing criteria are analyzed and compared with each other. Through the comparison, two main characters of the mapping design criteria are found. They are the harmonic mean of the minimum squared Euclidean distance and the average of Hamming distances with the nearest Euclidean distance.Based on these two characters, a novel mapping design criterion is proposed and a label mapping named mixed mapping is searched according to it. Simulation results show that mixed mapping performs better than the other mappings in BICM-ID system.     

闭环控制微波理疗机的设计

介绍了一种基于PIC16F877高性能单片机控制的微波理疗机的设计及系统工作原理,提出了闭环反馈功率控制方案,并较为详细的阐述了系统数据采集、D/A转换、功率调节等硬件电路设计,同时还指出了软件实现的特点。该理疗机输出功率范围为30~150W,并具有数字显示,报警提示等功能。     

基于PIC单片机的以太网数据采集与控制电路设计

本文介绍了由单片机控制的基于以太网的数据采集电路．该电路采用了美国Microchip公司的8位单片机PIC16F877和台湾Realtek公司的10M以太网控制芯片RTL8019AS．实现了数据采集以及以太网数据传输的功能。整个电路主要包括网络接1：7电路，单片机电路，A，D转换电路，D，A转换电路，RAM存储电路，EEPROM存储电路，D10电路等。文中简单阐述了以太网数据采集电路的设计原理，并给出了其实现的方法。     

用PIC16C73单片机实现十二位A/D转换器

介绍用PIC16C73自带的八位A/D转换器扩展为十二位A/D转换器,给出了具体的设计方案和程序流程。它是用以PIC16C73为MCU构成的海水有机磷测控仪A/D转换部分的一种解决方案。     

嗜盐菌AB3中细菌视紫红质和系统发育研究

为了研究分析嗜盐古生菌物种与细菌视紫红质(BR)蛋白基因资源,分离纯化得到极端嗜盐古生菌AB3. 采用聚合酶链式反应(PCR)方法对其编码螺旋C至螺旋G的蛋白基因片断和16S rRNA基因进行了扩增,并测定了基因的核苷酸序列. 翻译出的氨基酸序列与已报道的相应片断进行对比,AB3中的螺旋C至螺旋G蛋白与其他菌株差异显著.基于BR蛋白和16S rDNA序列的同源性比较以及系统发育学研究表明,AB3是Natrinema属中的新成员. 菌株AB3的16S rDNA序列已被GenBank数据库收录,其序列号为AY277583.     

上海市地铁驾驶员人格特征分析

采用卡特尔16种人格因素测试问卷对205名上海市地铁驾驶员(男185名,女20名)进行了测试,并将结果与全国成人常模进行比较。结果发现:上海市地铁驾驶员的恃强性、敢为性、兴奋性、幻想性、自律性的因子分显著高于普通成人(P<0.01);怀疑性、独立性因子分显著低于普通成人(P<0.01)。结果表明:上海地铁驾驶员的人格特征体现出高恃强性、高敢为性、高兴奋性、高幻想性、高自律性和低怀疑性、低独立性的人格特征。