离子注入中温升的研究

探讨了离子注入中的温升问题.这种温升可用试验方法进行测量.研究了几种测温方法(例如低熔点金属法和硬度法).分析了降低注入样品温升的一些途径.     

中国煤炭经济研究现状与展望

从研究机构、研究内容、研完方法及手段,多视角介绍了中国煤炭经济研究的现状;对煤炭工业管理体制、煤炭产业结构、煤炭工业投资、煤炭价格、煤炭劳动经济等多项专题研究成果进行了综述;并据此,对今后中国煤炭经济研究的内容、特点、方法、手段等进行了展望。使读者能较全面地了解中国煤炭经济研究的全貌,以供读者在工作、学习和研究中参考。     

用VBA在Word中二次开发试题库

用VBA语言(Visud Basic for Application)在Word中二次开发试题库,实现了试题文本的控制、人机交互功能.     

Comparative chromosome mapping of a conserved homoeo box region in mouse and human

Specific genes are assumed to regulate pattern formation in the mammalian embryo, but as yet none has been identified unequivocally. It is possible that such genes in mammals may be identified by virtue of a conserved coding sequence, because many of the Drosophila melanogaster homoeotic and segmentation genes, which have crucial roles in the regulation of segmental pattern formation during embryonic development, contain a 180-base pair (bp) DNA sequence, the homoeo box, and that sequences homologous to the Drosophila homoeo box are also present in 6-10 copies in higher animals, including mammals. Although the assumption that the homoeo box identifies genes responsible for pattern formation in mammals remains to be validated, it is a particularly attractive hypothesis given the strong conservation of homoeo boxes over vast evolutionary distances. Here we report the localization of a human homoeo box region, previously cloned and shown to contain two homoeo boxes within a sequence of 5-kilobases (kb), to the long arm of chromosome 17. We show that two single-copy homoeo box-flanking probes derived from this region strongly hybridize to single-copy restriction fragments in mouse genomic DNA and that these conserved homoeo box-flanking sequences map to mouse chromosome 11. This may be significant as several genes that map to chromosome 17 in human also map to chromosome 11 in the mouse, implying that a segment of mouse chromosome 11 is homologous to a region of human chromosome 17. Taken together, these data suggest that the homoeo box region detected with our probes is highly conserved in human and mouse.     

关于孪生素数猜想与一个配对问题

本文研究 p h=P_r,p≤x 的解数的阶,所得到的上界恰为人们长期猜测的 c_hxln~(-2)x(lnlnz)~(r-1),而下界与此预料为正确的阶只差一个阶因子 lnlnz.利用这些结果,我们顺便推广和改进了 E.K.S.Ng 与张明尧关于配对问题的工作.     

有限Hausdorff拓扑半群上概率测度卷积序列的弱收敛性

在非同分布场合下,拓扑群(半群)上随机变量卷积序列极限存在的充要条件是一个至今尚未得到解决的问题,但是在有限群时[1]得到一些重要结果,本文的主要目的是将[1]中的定理1,定理2推广到一类有限半群上。     

LOWER BOUNDS OF RAMSEY NUMBERS

The lower bounds for any R(l_1,…,l_q;r)are investigated.Let K_n~r be the completer-uniform hypergraph on n points.Define R(l_1,…,l_q;r)as the minimal natural number n sothat if the edges of K_n~r are q-colored,there is a set S of l_i(i∈{1,…,q})vertices such that alledges on S are of the i-th color.For the special case of q=r=2,the lower bounds were got byP.Erd(?)s and J.Spencer.In this paper,we shall give the lower bounds for any R(l_1,…,l_q;r).     

烫吸海洛因致海绵状白质脑病的临床分析

目的探讨海洛因中毒性脑病的诊断及影像学特征性改变的机制。方法结合文献分析本院的2例海洛因中毒性脑病患者的临床及MRI影像学特点、治疗经过及预后。2例患者均用大剂量维生素、激素、吡拉西坦、胞二磷胆碱、高压氧等对症支持治疗。结果2例均为烫吸海洛因患者,亚急性起病,以小脑性共济失调和口齿含糊不清伴饮水呛咳为突出表现。头颅MRI主要表现为双侧基底节区,小脑半球及脑干白质内具有散在、对称性的大片状长T1、长T2异常信号。1例好转出院,1例病情无变化自动出院。结论海洛因中毒性脑病诊断的主要依据是明确的海洛因吸毒史及特殊的体征以及与吸毒途径可能相关的特征性影像学改变。     

重组胸腺素α1在大肠杆菌中的融合表达及培养条件的优化

采用三角摇瓶来摸索BL21(DE3)/pET28A-Tα1菌种表达目的蛋白的最优发酵条件,并在此基础上在Biotop CF-5L自动控制发酵罐中,利用补料分批培养技术,流加甘油,进行发酵培养;利用Western blotting进行发酵产物鉴定. 摇瓶培养最优条件:10%接种量、25 mL LB培养基、37 ℃培养, 0.02 g/mL的甘油做碳源,接种后4 h加入终浓度为0.75 mmol/L的IPTG,诱导3h后目的蛋白表达量最高. BL21(DE3)/pET28A-Tα1菌种在Biotop CF-5L自动控制发酵罐中的条件为:以10%的接种量接种到3L发酵培养基中,设定溶氧40%,pH7.0,温度37 ℃,通气量3 L/min,快速流加甘油60 g ,培养4 h后,加入终浓度为0.75 mmol/L的IPTG,诱导3 h后终止发酵. 发酵罐中获得的菌体量为36 g/L,蛋白表达率为10%左右.