吉比特里所码和卷积码级联译码器设计

针对60-GHz无线个域网,提出了一种吉比特里所码和卷积码级联译码器架构。在推荐级联架构中,里所码和卷积码分别作为外码和内码,通过交织器级联。采用基于Viterbi算法的8路并行卷积译码结构和基于RiBM算法的里所码译码结构,实现了超高速级联译码器。在TSMC 0.13μm CMOS工艺下,该译码器以0.135 nJ/bit和5.19 mm2的能耗资源开销实现了高达2 Gb/s的吞吐率。     

7-取代吲哚类化合物合成及官能团化研究进展

7-取代吲哚化合物是合成药物及精细化学品的重要中间体.本文综述了近15年金属Pd催化的7-取代吲哚化合物的制备方法,将其分成直接合成法和吲哚7位官能团化法两类,对每一类的反应过程和机理进行了详细介绍和评述.     

1-环丙基-7-氯-6-(1-哌嗪基)-4-氧-1,4-二氢-3-喹啉羧酸盐酸盐的熔化与离解性质研究

1－环丙基－7－氯－6－（1－哌嗪基）－4－氧－1，4－二氢－3－喹啉羧酸盐酸盐为环丙沙星合成中主要的杂质之一，研究其物化性质对于改善环丙沙星的结晶分离提纯具有重要意义。本文研究了1－环丙基－7－氯－6－（1－哌嗪基）－4－氧－1，4－二氢－3－喹啉羧酸盐酸盐的熔化，分解特性，溶解度与离子强度，温度和pH值的关系，并测定了该物质的离解常数，估算了该物质在水溶液中的活度积。     

Role of La2O3 in Pd-Supported Catalysts for Methanol Decomposition

Systems of Pd supported on various La₂O₃-modified -Al₂O₃ and CeO₂–Al₂O₃ catalysts were tested for catalytic methanol decomposition and characterized by means of XRD, BET, TPR, H₂-chemisorption and CO–FTIR. The addition of lanthanum significantly improved the selectivity of CO and H₂ for all the catalysts but showed a different influence on the catalytic activity in two systems. Methanol conversion decreased on La₂O₃-modified Pd/-Al₂O₃ catalysts, in line with the reduction of Pd dispersion, while the addition of La₂O₃ improved the dispersion of Pd and reinforced Pd–CeO₂ interaction for La₂O₃-modified Pd/CeO₂–Al₂O₃ catalysts, which resulted in a high production rate of CO and H₂. Thus, a synergistic effect between CeO₂ and La₂O₃ was observed on -Al₂O₃-supported Pd catalyst for methanol decomposition.     

6，7-二氢-5H-环戊烷并[b]吡啶

6,7-二氢-5H-环戊烷并[b]吡啶主要用于药物、杀菌剂和抗菌剂的研究,也被广泛应用于制备植物保护剂和合成树脂、防老剂以及塑料制品等。目前因其被作为第四代抗生素头孢匹罗的侧链而成为研究者竞相开发的热点。6,7-二氢-5H-环戊烷并[b]吡啶有实用价值的合成方法主要有N-羟基邻苯二甲酰胺法、丙烯醛法和己二酸二乙酯法。丙烯醛法中6,7-二氢-5H-环戊烷并[b]吡啶的收率为87.4%,具有较好的开发前景。     

A molecular level mechanism ofn-butane oxidation to maleic anhydride over vanadyl pyrophosphate

A molecular level mechanism is proposed for the highly selective 14-e^– oxidative transformation ofn-butane to maleic anhydride on the surface of vanadyl pyrophosphate. The mechanism suggests that the dimeric active sites assume at any given time, one of four possible interconvertible states which differ from each other in the number of available oxygen atoms and the formal oxidation states of the individual vanadium atoms. The relative ratios of active sites in each of the four possible states are dictated by the reaction conditions, the redox properties of the reacting gases and the structure of the vanadyl pyrophosphate active surface. A crucial feature of the mechanism is a pseudo-ozonide surface species formed by the interaction of a chemisorbed dioxygen molecule and an adjacent metal-oxo group. This unusual species is responsible for the initial activation of then-butane, which occurs when the chemisorbed dioxygen abstracts an H-atom from the alkane and the adjacent metal-oxo group reacts with the incipient alkyl radical to form an alkoxy group. The proposed mechanism is entirely consistent with literature reports describing the behaviour of (VO)₂P₂O₇ in flow, pulse and TAP reactors.     

PC-DCS关键技术研究

结合一个工控系统实例，介绍了一种PC－DCS系统数据刷新频率的方法，提出从使用智能通信卡，多串口通信，通信数据组织，以及测控仪表选型等全方位着手提高系统通信实时性的新思路。     

Bioactive IL7-diphtheria fusion toxin secreted by mammalian cells

A number of targeted cytotoxic agents have been developed that selectively kill malignant or otherwise pathological cells. These engineered proteins consist of a potent cytotoxic element connected to a ligand domain that binds to specific molecules on the surface of the target cell. Several of these agents have shown promise in clinical trials and one is currently administered to patients. A significant technical obstacle that has impeded the development of some of these toxins is the difficulty of preparing certain recombinant proteins in properly folded forms. These fusion proteins have generally been produced in bacteria requiring them to be denatured and renatured in vitro. For some proteins this is an efficient process whereas for others it is not. We describe here a system to produce fusion toxins rapidly and efficiently by engineering mammalian cells to secrete them as properly folded molecules which can be purified in native form from cell culture medium. We have used this system to produce highly active preparations of DAB(389)-IL7, a molecule consisting of the catalytic and transmembrane domains of diphtheria toxin fused to interleukin 7. This system is generalizable and can be used to produce and evaluate rapidly fusion toxins incorporating novel or uncharacterized ligands.     

我国食品理化检验标准体系的发展趋势分析

GB/T5009体系是我国最重要的食品理化检验标准体系之一,历经多年的发展,现已日趋成熟。本文对现有的GB/T5009体系从组成、发展、特点及存在的问题进行了分析归纳,对未来食品理化检验标准体系的发展趋势进行了较为系统的总结。     

基于RS485总线的多编码器数据采集系统研制及改进验证

为解决某型航空发动机高压压气机静子叶片角度安装精度问题,设计了基于RS485总线的多编码器数据采集系统,详细介绍了系统的结构以及改进方案。方案均在实际中得到验证,具有一定的工程参考价值。