TEMIC射频卡的速率自适应读卡算法

提出种基于TEMIC射频卡Manchester编码的速率自适应读卡算法,并对该算法进行了说明和示例。     

Peptides-XXXXVI: Studies in the synthesis of an analogue of hen egg white lysozyme

The previously synthesised (1–37), (38–75), (76–93), (94–104), (105–117) and (118–129) fragments of the analogue were combined making extensive use of the DCCI/HONSu method. The final coupling involved the (1–75) and (76–129) sub-fragments. Aggregation of the latter fragment caused problems in purification by routine gel filtration methods employing Enzacryl K2 or Sephadex LH60. The fully protected (1–129) product was partially purified by washing, then deprotectcd and purified by gel filtration and ion exchange chromatography. Satisfactory removal of the acetamidomethyl group used for cysteine protection could not be achieved.     

Rearrangement during cyclisation of some 3-(2-pyrrolyl) propionic acids and related compounds

Cyclisation of the title compounds leads to mixtures of the expected 4H-cyclopental[b]pyrrol-4-ones (1), the corresponding 6-ones (3) by a single rearrangement, and the cyclopenta[c]pyrrol-4-ones (4) by a double rearrangement, the proportions depending upon the substituents.The ¹H NMR spectra of 2-methyl-4H-cyctopenta[b]thiophen-6-one (3f) shows 6J long range $\text{CH}{}_3\text{CH}{}_2$ coupling, but this is absent in the corresponding pyrroles (3c,d). The ¹³C spectra of 1 and 3 cannot be interpreted on the basis of substituent chemical shifts in pyrroles and thiophens, and are clearly -CH = CH-X (X = NMe, NPh, S) bridged derivatives of cyclopent-2-enone.     

基于半导体光放大器进行光标签提取的性能分析

利用半导体光放大器增益饱和数学模型,第一次分析了基于单个半导体放大器进行光标签提取的节点性能.通过对半导体光放大器的参量分析和优化,仿真显示,对于标签速率2.5 Gb/ s 、净荷速率40 Gb/s 的光分组包,提取的标签消光比可达到13 dB.     

RFID系统防碰撞算法的研究及其改进

射频识别技术中,防碰撞问题是提高系统读取效率的关键问题。文章在传统防碰撞算法的基础上,分析了ALOHA的防碰撞算法和二进制搜索算法。并提出一种改进的动态二进制搜索算法。利用曼彻斯特编码可以准确识别碰撞位的特性,当读写器检测到碰撞位之后,仅需要记录最高碰撞位和次高碰撞位的位置,并设定这两个位置上的比特数作为下次查询命令,从而使系统的传输数据量、传输时间大大减少,改进后的算法比二进制搜索算法更具优势。     

The crystal structure of bicyclo [3.3.3]undecane-1,5-diol and the conformation of bicyclo[3.3.3]undecane (manxane)

The crystal structure of bicyclo [3.3.3]undecane-1,5-diol has been determined. It is monoclinic, P2₁/c, a = 12.99(2), b = 14.16(2), c = 12.50(1)A,β = 112.42(2)°, with two independent molecules in the asymmetric unit. One of these is disordered, but the other has almost exact C_3h symmetry and its conformation and precise molecular geometry agree well with previous calculations by molecular mechanics. The molecule shows considerable angle strain, having bridge angles in the range 118–121°     

Peptides—XXXV: Synthesis of the 17–26 fragment of a lysozyme analogue

The fully protected 17–26 fragment of a lysozyme analogue has been synthesised. A fragment condensation approach has been employed using the protected subfragments 17–19, 20–22 and 23–26. In the synthesis of the subfragments the use of the diphenylphosphinyl mixed anhydride method has been demonstrated.     

视频成像测井光缆传输系统井上电路设计

文章描述了一种基于FPGA实现的井上电路.该电路基于光缆传输机制,采用光模块完成光电转换,在FPGA内实现高速串行数据的数据恢复和曼彻斯特解码等处理,经视频模块处理后,完成对井下视频信息的恢复.其中,高速串行数据的数据恢复采用了过采样的处理方法.该电路结构简单、可靠性较高,与井下电路配合使用,可实现井下视频信号的可靠采集.     

一种基于1553B总线的数据采集终端设计

本文介绍了一款针对于1553B总线的数据采集终端的设计方法。该款终端在整个系统中,具备有特定的终端号,其功能是：将采集好的数据存储于FPGA中,当终端接到总线控制器的命令后,把存储的数据按要求发至1553B总线上。     

预测校正型曼Ⅱ码译码器技术研究与实现

文章针对计算机系统中串行总线的通讯,提出并实现了一种预测校正型曼Ⅱ码译码器.以预测校正型方式实现的曼Ⅱ码译码器,极大的提高了总线通讯的可靠性,节省了硬件资源,提高了系统的速度.该译码器已经应用于1553B总线控制器LS-FT33中,至今运行可靠.