~(230)Acβ延发裂变的观测(英文)

搜索了２３０Ａｃβ延发裂变．由 ６０ＭｅＶ／ｕ１８Ｏ离子照射２３２Ｔｈ，通过多核子转移反应产生２３０Ｒａ．经放射化学分离和薄的２３０Ｒａ→β－２３０Ａｃ源的制备，获得了 １０８ 个２３０Ａｃ原子．该源对云母裂变径迹探测器曝光．借助于所测的γ能谱和两个裂变事件，鉴别了β延发裂变核２３０Ａｃ，得到了它的β延发裂变几率为（１． １９± ０．８５）× １０－８．

2007年辽宁省特大暴风雪形成过程与危害

2007年3月初辽宁发生了有气象记录以来最大的暴风雪灾害。在对2007年3月3—5日辽宁特大暴风雪和寒潮天气全面调查的基础上,系统分析了这次天气的强度、时空分布、形成过程和造成的危害。结果表明:本次暴风雪在辽宁省绝大部分地区出现了强降雪、降温及大风的天气特征,其中48h内全省平均积雪达20cm以上,最大降水量达106mm;最大风速为32m.s-1;主要的天气过程是500hPa高空槽、850hPa急流和切变及地面气旋的共同作用所致。这次特大暴风雪灾害给全省各行业造成了极大的经济损失。针对这场灾害的特点,提出了减轻和应对类似暴风雪灾害的建议和相应措施。

黄土丘陵沟壑区山坡道路防蚀措施初步研究

山坡道路连接农田、果园 ,对山区经济发展有重要作用。黄土高原山坡道路存在严重的水土流失 ,侵蚀方式主要有沟蚀、泻溜、崩塌、陷穴、悬沟侵蚀与滑坡等。山坡道路网应按照小流域综合治理规划合理布置 ,其主要防护措施 :①修筑梯田 ,防止坡面径流冲刷道路 ;②将路面整修成拱形以分散径流 ;③在道路内侧修蓄水窑窖 ,拦蓄径流 ;④路面及边坡栽植草灌 ,防止雨水冲刷

鸡粪中活性有机酸的分离与鉴定

本文通过生物追踪实验法 ,研究了鸡粪中有机酸的生物活性成分 ,并从中筛选出了一种强活性物质 .通过红外光谱和质谱及生源关系初步确定其分子式为C36H56O18Na,名称为 3-O -D -葡萄糖 -6,1 -0 -葡萄糖酸 2 β ,2 ,2 0 -二羟基蛋甾酸钠

Photo- and Thermo-Chromic Study of the Ethylenediamine Trimolybdate

The ethylenediamine trimolybdate (ENTMo) can show unusually photochromic and thermochromic properties and there exists in the difference of chromic mechanisms, which has been proved in our previous work [I]. In this paper, X-ray powder diffraction (XRD), Fourier transform infrared (FTIR) and laser Raman spectroscopy (LRS) of the colored samples are characterized and analyzed in detail. The crystal structure, the inorganic skeleton and the microenvironment of center ions of the colored samples do not substantively change except distortion. The color difference of the photochromic and the thermochromic samples is discussed and that the difference of reduction sites result in their different chromic mechanisms is suggested.

Synthesis of different gold nanostructures by solar radiation and their SERS spectroscopy

In this article, a simple and novel photochemical synthesis of different gold nanostructures is proposed using solar radiation. This method is rapid, convenient and of low cost, and can be performed under ambient conditions. By adjusting the concentration of sodium acetate (NaAc), different morphologies of the products can be easily obtained. Without NaAc, the products obtained are mainly polyhedral gold particles; lower concentration of NaAc (0.05 and 0.1 M) accelerates the formation of flowerlike gold nanostructures; while higher concentration of NaAc (0.5 M) facilitates the formation of a variety of gold nanowires and nanobelts. It is found that the morphology change of gold nanaostructures is the result of the synergistic effect of poly(diallyl dimethylammonium) chloride (PDDA), Ac- ions, and the pH value. In addition, the different gold nanostructures thus obtained were used as substrates for surface-enhanced Raman scattering (SERS) with p-aminothiophenol (p-ATP) as the probe molecule.

Ion-channel sensing of ferricyanide anion based on a supported bilayer lipid membrane

Ferricyanide anion has usually been used as a marker of ion-channel sensors. In this work we first found that ferricyanide, itself, can act as a stimulus to regulate the permeability of sBLM prepared from didodecyldimethylammonium bromide (a kind of synthetic lipid) on a GC electrode. We used cyclic voltammetry and a.c. impedance to investigate this phenomenon. The interaction between sBLM and ferricyanide concerns time. Furthermore, we developed a sensor for ferricyanide anion. The ion-channel sensor is highly sensitive. It can detect ferricyanide concentration as low as 5 muM.

稀土离子与红细胞作用的~(133)Cs NMR研究

随着稀土资源的不断开发利用,它们不可避免地通过多种途径进入生物体内,因而从分子和细胞水平上研究稀土的生物效应具有非常重要的理论和实际意义.关于稀土与细胞作用的研究已有诸多报道,本文报道用~(133)Cs NMR方法研究La~(3+)对Cs~+跨膜进入红细胞的影响.对于物质跨膜传输的研究,首先需要合适的手段将被传输物质在膜两侧的分布区分开.在碱金属离子中,仅~(133)Cs~+在不引入顺磁位移试剂情况下,细胞内外NMR信号能确切区分,并且在体系中无K~+时,Cs~+有类似于K~+的功能,故~(133)Cs是研究稀土离子与细胞作用

应用便携式微机伏安仪测定钯

用便携式微机伏安仪对贵金属Pd的电化学性能和测定进行了研究。在1 mol/L HCl溶液中Pd(Ⅱ)浓度2.5ng/ml～60μg/ml范围峰高是线性增加的。回收范围82％～105％。相对标准偏差为(n=8)3.8％。本法应用于贵金属回收液中Pd的测定,获得较为满意的结果。

Expression, purification of recombinant flounder MRF4 protein in Escherichia coli and analysis of its polyclonal antibodies

MRF4 is one of muscle regulatory factors and plays critical roles during skeletal muscle development. The muscle development is important for the fish growth which is an important economic factor for the fish culture. To analyze the function of MRF4 in fish, the founder MRF4 antibody was prepared. The flounder MRF4 was cloned, ligated into prokaryotic expression vector pET-30b and expressed in strain E. coli BL21 (130). The recombinant flounder MRF4 fusion protein was soluble and purified with cobalt IMAC resins. To prepare MRF4 polyclonal antibodies, rabbits were immunized with the soluble protein and the increasing level of antibodies was determined by Western blot. Also, the endogenous flounder MRF4 was recognized by the anti-serum. The result further proved the existence of the anti-MRF4 antibody in the anti-serum, which will be useful for studies on the function of flounder MRF4.

东太平洋海隆13°N附近热液硫化物形成过程

东太平洋海隆13°N附近热液区构造环境上属于快速扩张中心，该区段洋中脊拉张速率达到了12cm/yr，轴部地堑平均水深2630m。本文即是对该研究区（103°54.41´W, 12°42.68´N）获得的热液烟囱体硫化物样品展开了研究。借助偏光显微镜观察了硫化物显微结构特征，并分析了硫化物中的矿物组合。东太平洋海隆13°N附近热液硫化物中常见矿物为Fe硫化物和Zn硫化物，并经历了由早期Fe硫化物为主转变为晚期成熟化以Zn硫化物为主的过程；根据观察到的显微结构，东太平洋海隆13ºN附近热液硫化物的形成至少可划分出四个阶段即黄铁矿阶段、黄铜矿阶段、黄铁矿-闪锌矿和闪锌矿阶段。 建立了热液硫化物样品中常、微量元素的测试方法，测定了东太平洋海隆13°N附近常、微量元素组成，并与有沉积物覆盖的北胡安德富卡脊Middle Valley烟囱体硫化物和弧后环境的北斐济盆地富Zn型烟囱体硫化物进行了对比。以Cu、Pb、Zn相对含量百分比划分，东太平洋海隆13ºN附近热液硫化物属富Zn型。 阐述了东太平洋海隆13ºN附近热液硫化物微量元素组成空间变化特征及元素比值在样品中的演化，并分析了常微量元素之间及元素/Cu值与1/Cu之间的相关性。Cd、Ga、In主要以类质同像的形式存在于Zn硫化物中，Co的主要寄主矿物是Zn硫化物。在东太平洋海隆13°N附近热液硫化物的形成过程中，常量元素Cu、微量元素Mo趋向于在高温(T>300℃)条件下自流体相沉淀。对东太平洋海隆13°N附近热液硫化物而言，硫化物样品中Cu含量、Cu/Pb及Mo/Pb值可以为形成硫化物的流体的温度变化提供指示性佐证；对应于形成硫化物的流体温度由高温至低温的演化，流体化学组成也相应地发生了演化，其中Sr、Ba、Au等微量元素按指数函数规律富集。对获取的硫化物样品进行了R型因子分析，旋转后获得的因子可以区分出形成硫化物的流体的温度和化学组成这两个因素的影响。 在热力学计算的基础上绘制了东太平洋海隆13°N附近热液Fe-S-H2O系统布拜图，据此阐明了实际情况下东太平洋海隆13°N附近热液流体由高温至低温的过程中，硫化物中优势矿物黄铁矿的稳定场的演化。在此基础上结合已有的动力学实验和硫同位素分馏的研究成果，揭示了沉淀硫化物的热液活动过程中形成优势矿物黄铁矿的可能的主要化学反应历程和形成硫化物的流体的温度变化对黄铁矿形成的热力学机制的影响。