GaAs器件的离子注入新技术研究

本文介绍了离子注入技术中双偏角注入,大偏角注入和双向双偏注入等新工艺与使用效果。同时,阐析了BF~+对Si~+注入的沾污,以及以上研究在研制高水平GaAs器件中的关键作用。     

Evidence of phase separation in Nd1-xSrxMnO3 （x=0.50, 0.51, 0.52, 0.53, 0.54, 0.55）

The temperature dependence of Mn ion magnetization and the conductivity difference versus temperature provide phase separation evidence in Nd1-xSrxMnO3 (x=0.50, 0.51, 0.52, 0.53, 0.54, 0.55). This is different from other reports and may suggest that a fully charge-ordered state exists in quite a narrow range; the sample preparation procedure affects the charge ordering. The polaron effect also plays an important role in explaining the conductivity.     

多元线性模型中均值矩阵的函数的所有可容许线性估计

对于多元正态线性模型Ｙｎ×ｍ￣Ｎ（Ｘ－，Σ×Ｖ），Ｖ≥０和Σ≥０已知，在三种不同的可容许性意义下，该文分别得到了ＳＸ－的线性估计ＬＹ＋Ｄ在一切估计类中可容许的充要条件。     

新编应用题选登

题 70　 在某军事演习中 ,舰艇Ａ以每小时30海里速度向正北方向航行 ,发现在该舰艇正东方向 4 0海里的上空 10千米Ｃ处有一敌机 ,测得其速度为 2 4 0千米 /小时 ,方向是北偏西 6 0°,飞行轨道是与海平面平行的直线 .1)问敌机与舰艇间的最短距离为多少 ?2 )舰艇发现敌机后 ,立即向其发射炮弹 ,30秒后击中目标 ,问炮弹发射的速度、方位角、仰角各是多少 ?(空气阻力及舰艇速度对发射炮弹的影响均忽略不计 .取 1海里 =1.8ｋｍ ,结果精确到 0 .1)图 1　题 70图解　如图 1,平面α表示海平面 ,飞行轨道直线ｌ在α内的射影为ｌ′ ,Ｋ为ｌ′与舰艇Ａ…     

SELECTION OF RECOMBINANT VACCINIA VIRUSES (TIAN TAN STRAIN) EXPRESSING HEPATITIS B VIRUS SURFACE ANTIGEN BY USING β-GALACTOSIDASE AS A MARKER*

We constructed a plasmid that contains a small piece of DNA with two vaccinis promoters running in opposite directions——a promoter from a late gene encoding an 11 K polypeptide (P11) and a promoter from an early gene encoding 25K(P25). These promoters were isolated from the Tian Tan strain of vaccinia virus and were flanked by the thymidine kinase (TK) sequence of the same virus. Genes encoding the hepatitis B virus surface antigen (HBsAg) and the Rscherichia coli β-galactosidase (LacZ) were inserted downstream of the 11 K and 25 K promoters respectively so that coexpression plasmids were constructed. Recombinant vaccinis Viruses were selected directly by picking blue plaques formed under overlaying agarose medium containing X-gal. HBsAg was expressed to high level by these recombinant viruses. These recombinant viruses showed reduced virulence on rabbit skin and induced anti-HBs after intrsdermal inoculation of rabbits.     

高速摄影胶片的数值自动分析研究

本文介绍一种自行研制的高速摄影胶片的自动分析系统。记录物体冲击，爆炸或高速运动的胶片通过可定画幅控制的胶片传送机构，由摄像机将图像转化成电信号，并存储在数字图像２处理系统中，通过乍分析软件对特征点进行提取和相关匹配分析，可确定运动物体上各种特征占的运动变化。同时该系统还具备消除摄影像系统畸变影响的功能，确保数据处理的精度。     

模2N的0/1平衡背包的构造

证明了模2^N的0/1平衡背包与重量矩阵为上三角阵的标准平衡背包等价，且2^N(N-1)/2N!