扩频系统中自动频率校正单元的设计与实现

针对ＩＳ－９５码分多址蜂窝通信系统标准,给出了一种在从导引信道上提取信道参数并同时获取对载频频差的估计方案,给出了自动频率校正环路的设计方案,及其ＦＰＧＡ实现。该方案简单可行,硬件资源消耗少,且能明显改善移动台接收机的性能。     

Cloning, construction of prokaryotic expression vector and expression ofEscherichia coli cytosine deaminase gene

Cytosine deaminase gene ofEscherichia coli strain H-30 was cloned, and its initiation codon of ‘GTG’ was mutated to ‘ATG’ by PCR. Prokaryotic recombinant expression vector pBV220-CD was constructed. Clone with high enzyme activity were selected by detecting their specific activity of cytosine deaminase. 5-FC(5-FC, 5-fluorocytosine) could induce the lethal toxicity to cells containing active CD gene. DNA sequence analysis indicated that there were 16 altered bases and 5 of them resulted in the alteration of amino acids in predicted peptide by comparing DNA sequence of the clone H-30-CD-11 with high enzyme activity with CD gene reported in Gene Bank.     

Diamond synthesis from a system of chromium-carbide and Ni70Mn25Co5 alloy

In order to ascertain the mechanism of interaction between carbide and metallic catalyst and formation of diamond under high pressure and high temperature, and find a new method to synthesize diamond with special properties, it is necessary to investigate the reaction behavior of different carbides and metallic solvent_catalysts under high pressure and high temperature. A system of Cr-3C-2 powder and Ni 70Mn 25Co 5 alloy in weight ratio of 1∶6 was treated under 6 0 GPa and 1 500℃ for 20, 30 or 60 min respectively. X_ray diffraction of the samples indicated the Cr 3C 2 decomposed partially after high pressure and temperature treatment, and Cr 7C 3, Cr and diamond formed respectively. There was not any trace of graphite in the samples. The result suggested that the separated carbon atoms could form diamond directly without conversion process of graphite into diamond. The observation of SEI, WDX and EDX also showed that diamond crystals were synthesized in the system, which have perfect surfaces and shapes, with the average grain size of about 40 μm. The properties of the crystals are being investigated.     

Construction of High Level Expression Cell Lines of Erythropoietin *

Ｅｒｙｔｈｒｏｐｏｉｅｔｉｎ（ＥＰＯ）ｉｓｏｎｅｏｆｔｈｅｍｏｓｔｉｍｐｏｒｔａｎｔｒｅｇｕｌａｔｏｒｙｆａｃｔｏｒｓｄｕｒｉｎｇｔｈｅｄｅｖｅｌｏｐｍｅｎｔｏｆｍａｍｍａｌｉａｎｅｒｙｔｈｒｏｃｙｔｅ,ａｃｔｉｎｇｍａｉｎｌｙｏｎｔｈｅｅｒｙｔｈｒ...     

SrxBa1—xTiO3陶瓷的频域介电谱

用固相反应法制备ＳｒｘＢａ１－ｘＴｉＯ３系列陶瓷．当ｘ＝０．３０时呈现显著的驰豫相变特征．在５Ｈｚ至１ＭＨｚ范围,相对介电常数的实部ε′随频率ｆ的降低而增大．１／ε′与ｌｇｆ的关系曲线呈现折曲的２段直线．高频相对介电常数的实部ε′ｈ随ｘ的增加而增大是与顺电相的增加而对应．测量点（ε′,ε″）随频率ｆ的变化分布在复平面的一条直线上．     

FD-TRT耐热逆转录酶的特性分析

从嗜热细菌ＦＤ３００９中克隆并分离纯化得到的耐热逆转录酶（ＦＤ－ＴＲＴ）,逆转录反应在６５℃高温下进行,可克服常温逆转录酶的许多缺点,以酵母核糖体ｒＲＮＡ为模板,以与２５５和１８Ｓ ｒＲＮＡ匹配的寡聚脱氧核苷酸为引物,探明了ＦＤ－ＴＲＴ的最适反应条件： ２５ｍｍｏｌ／Ｌ Ｔｒｉｓ－ＨＣｌ（ｐＨ ８．５,２５℃）,２５ ｍｍｏｌ／Ｌ（ＮＨ４）２ＳＯ４,２ ｍｍｏｌ／Ｌ ＭｎＣｌ２,１００ μｇ／ｍｌ明胶．５ ｕｎｉｔ ＲＮａｓｉｎ,２５０ ｍｍｏｌ／Ｌ ４种 ｄＮＴＰ, １μＣｉ３ Ｈ－ｄＣＴＰ, １２ｕｇ ＲＮＡ,２５ ｐｍｏｌ引物,并在此条件下测得 ＦＤ－ＴＲＴ和 Ｔａｑ ＤＮＡ 聚合酶逆转录活力与聚合酶活力的相对比值分别为０．０５６,０．００４５．     

稀土元素(镝、钬、铒、铥、镱、镥、钇和钪)高分辨率ICP光谱谱线表与光谱图的编制

讨论并建立了高分辨率光谱仪参数,在带宽为3pm的光谱条件下摄取了稀土元素的高分辨率等离子发射光谱（ICP）,鉴定了在240～450um波长范围内的谱线,和估测了这些谱线的强度．在实验中也观测到了谱线复杂的物理轮廓,包括超精细结构和未完全分辨的定线轮廓．     

氩离子腔内倍频紫外连续激光器

本文从讨论培频效率入手,分析了影响倍频效率的原因,给出BBO晶体氩离子腔内培频紫外激光器的设计方案,制作了激光器,并得到了紫外激光输出。     

磁卡读,写控制器的研制

介绍了一种独立的、自成体系的磁卡读／写控制器,提出了该系统的软硬件设计的基本思想和技术特点。     

Ru原子高Rydberg态能级的唯象势计算

将文[4]提出的用于碱金属原子的唯象势推广到一般原子的高Rydberg态,并对Ru原子4d7（4F）ns（n＝28－45）和4d7（4F）nd（＝26－48）系列的Ryd－berg能级进行PWKB计算．在理论值与实验数据之间进行比较的基础上,讨论了所得结果的物理意义．