黑蝉(C.Atrata Fabricius.)发声声学的研究

黑蝉发声膜的长肋可类比为一端夹紧的梁,激励声的基频为3900—5500Hz,与黑蝉鸣声的主峰频率(MPF)的可能范围基本一致。有盖(Op)、鼓盖(TC)和褶膜(JM)可分别类比为一边固定、二边固定其余自由的均匀方板和四边固定的矩形膜,受激振动的基频(f_(OP)~1=940Hz、f_(TC)~1=1200Hz和f_(JM)~1=810Hz),及其f_(OP)~(3,4.5,5,5.5,6)、f_(TC)~(2,2.5,3,3.5)和f_(JM)~(45,65,66,76,77)分别与Op、TC和JM振动的MPF及其主要高频成分基本相一致,共鸣腔和两侧气门可类比为并联谐振电路和并接于输出端的电阻,谐振频率和品质因素与黑蝉鸣声的MPF和调谐度基本相一致。     

谷氨酸在乳状液膜中的迁移行为

用氯化三等基·甲基铵（Ａｌｉｑｕａｔ ３３６）－Ｓｐａｎ８０－甲苯制成的乳状液膜体系对谷氨酸的迁移行为进行了研究,２ ｍｉｎ的迁移率可达９３％。在谷氨酸的最佳迁移条件下,油溶性好的苯丙氨酸迁移率较高,但油溶性低的甘氨酸和碱性氨基酸的迁移率明显较低。此法适用于微量氨基酸的提取和分离。     

类铝离子Cr+11、Mn+12和Fe+13能级3s23p-3s23d跃迁参数计算

用多组态Dirac-Fock(MCDF)方法,对类铝离子Cr⁺¹¹、Mn⁺¹²和Fe⁺¹³能级3s²3p-3s²3d跃迁进行了理论计算。研究了组态相互作用对类铝离子跃迁的影响,得到了相应的跃迁能量、跃迁波长和振子强度。与已有的实验数据进行了比较,相应的计算结果符合较好。     

基于INTERNET技术的基础力学无纸考试系统

本系统利用现代信息技术和计算机网络技术,开发了基于INTERNET技术的,以大型数据库为基础的基础力学无纸考试系统,该系统融试题库管理,教师组卷,学生考试,自动改卷,成绩查询和统计分析,课程管理,教师管理,学生管理于一体,进行客观考试,大大提高了考试的可信度和效率。     

三波长分光光度法研究纳米TiO2对Hg2+的光催化还原效果

利用自制微型纳米TiO₂光催化反应器对不同初始浓度的Hg²⁺溶液进行光催化还原实验,利用Hg²⁺-硫氰酸盐-罗丹明B离子缔合物分光光度法测定溶液中剩余Hg²⁺的浓度,表征Hg²⁺的光催化还原效果.采用三波长分光光度法有效地消除了TiO₂悬浮体系中的浑浊对测定的干扰.讨论了光催化还原的最佳条件及其在消除工业废水中有毒物质Hg(Ⅱ)方面的应用.结果表明:纳米TiO₂对低浓度Hg²⁺溶液光催化还原效果显著,还原率可达90%以上,并且可以大幅降低工业废水中Hg(Ⅱ)的浓度.     

辐射诱导促进AdCMV-p53 转染前列腺癌细胞

用腺病毒重组体（AdCMV p53/GFP）转染经0.5, 1.0和2.0 Gy γ射线辐射处理的前列腺癌细胞[PC 3（ nullp53）], 用克隆形成法检测细胞增殖能力, 用流式细胞分析法测定腺病毒重组体转染率和外源性p53蛋白表达。 结果提示, 辐射诱导使腺病毒重组体转染PC 3细胞提高7%—39%。 辐射联合 AdCMV p53 转染组p53表达水平提高18.5%—35.4%。 与单纯 AdCMV p53 转染组和单纯辐射组相比, 辐射联合 AdCMV-p53 转染组细胞存活率分别降低25%—64%和22%—65%。 To determine whether low dose pre irradiation could enhance adenovirus mediated p53 transfer and expression in human prostate adenocarcinoma, the PC 3 cells were pre exposed to γ rays, and then infected with replication deficient adenovirus recombinant vectors, containing human wild type p53 (AdCMV p53) or green fluorescent protein gene (AdCMV GFP) respectively (γ ray irradiation + AdCMV p53 /GFP infection). The exogenous gene transfer and expression were detected by flow cytometric analysis. The GFP transfer frequencies in γ irradiation + AdCMV GFP infection groups were 7%—39% more than those in AdCMV GFP infection groups. The p53 levels in the γ irradiation + AdCMV p53 infection groups were 18.5%—35.4% more than those in AdCMV p53 infection groups (p<0.05),suggesting that low dose (less than or equal to 1.0 Gy) irradiation could significantly promote exogenous p53 transfer and expression in the PC 3 cells. The survival fractions for the γ irradiation + AdCMV p53 infection groups were 25%—64%, 22%—65% less than those for AdCMV p53 infection, or γ irradiation groups, respectively (p<0.05).     

中国科学院近代物理研究所重离子束治癌进展

介绍了中国科学院近代物理研究所在重离子束治癌研究和治疗装置研制方面的最新进展, 以及中国科学院近代物理研究所重离子束治癌的发展规划。     

特异性抗癌因子——凋亡素

凋亡素是一种抗癌因子, 能以非p53依赖性途径诱导不同类型人肿瘤细胞的凋亡, 不受Bcl 2的抑制作用, 且对正常细胞不起作用。 根据凋亡素的肿瘤特异性, 可将其作为一种极具潜力的抗肿瘤生物制剂, 在人体内大量传递给肿瘤细胞, 有选择性地根除肿瘤细胞。 论述了凋亡素抗肿瘤细胞的作用机理, 并对其应用现状、 前景及进一步研究的主要问题予以简要评述。Apoptin is an anti cancer gene. It can induce p53 independent,Bcl 2 insensitive type of apoptosis in various human tumor cells,and fails to induce programmed cell death in normal cell. Because of having tumor specificity, apoptin can be transferred enough to tumor cell in vivo,selectly kill the tumor as a potential anti tumor biological preparation. In this paper, we provide a brief review on the anti cancer mechanism of apoptin, current status and application prospect, and the main issues in apoptin studies.     

Application of shell model in molecular dynamics simulation to MgO

The P－V－T equation of state of MgO has been simulated under high pressure and elevated temperature using the molecular dynamics (MD) method with the breathing shell model (BSM). It is found that the MD simulation with BSM is very successful in reproducing accurately the measured molar volumes of MgO over a wide range of temperature and pressure. In addition, the MD simulation reproduces accurately the measured volume compression data of MgO up to 100GPa at 300K. It is demonstrated that the MD simulated P－V－T equation of state of MgO could be applied as a useful internal pressure calibration standard at elevated temperatures and high pressures.     

基于半波差分谱的语音信号音节切分

根据听觉感知系统对于动态语音特征的响应特点,提出了半波差分港的概念,在此基础上提出了一种简便的音节切分算法,可以将存在大量协同发音现象的连续语音切分成一个个音节。在连续语音上的切分实验结果说明这种切分算法是准确而可靠的．