Paleomagnetic Results of Later Paleozolic Rocks From Alashan Area of Western North China Block

In order to contribute to the Apparent Polar Wander Path (APWP) of the North China Block (NCB) , we collected paleomagnetic samples of Late Paleozoic rocks from the northern and southern margins of the Alashan (Alxa) terrane (the western part of Inner Mongolia and northern parts of Gansu and Ningxia Provinces) and adjacent regions. Laboratory work revealed different types of demagnetization behavior and isolated a higher temperature characteristic component in most of the samples. Results of IRM experiments show high thermal stability and high coercivities for the magnetic carriers in these rocks. The characteristic component passed the fold and/or reversal tests, suggesting that the characteristic components were probably primary. On the basis of comparing the paleomagnetic results with the geologic evidence, we discuss the tectonic implications. In the Late Paleozoic, the Alashan region had been part of the NCB and was not connected with the northern and southern blocks. During the Carboniferous Alash     

TRANSFER OF FOREIGN GENES BY ELECTROPORATION AND THEIR EXPRESSION IN MAMMALIAN CELLS

Expression of foreign genes transferred into mammalian cells by electroporation has been studied. The pX1TK gene, pSV2Neo gene and pUCEJ oncogene have been introduced into MLTK-cells and NIH/3T3 cells, respectively. Stable transformation transient expression of TK gene by MLTK-cells as well as stable and malignant transformation of NIH/3T3 cells have been obtained. Transient expression frequency is about 80% and stable transformation frequency is about 10~(-4). Integration of foreign genes into the cellular genome was verified with molecular hybridization. Tumor development was observed after inoculation of transformed celts into nude mice.     

SA耐火材料多晶结构与性能的研究

本实验采用磨具废砂和炉皮SiC废砂生产SA耐火材料，通过XRD分析和计算机处理确定各试样中的晶相（4H－SiC，33R－SiC，3C－SiC，α－Al2O3，β-石英和Al6Si2O13）及其各相的含量。通过材料性能与结构综合分析，确定较好的配方，其含量：磨具废砂50％，炉皮砂45％，结合剂5％，外加矿化剂2％。     

Studies of a new series of ion-pair complexes [Mo(dtc)_4][Ln(dtc)_4] (Ln=La-Er,exp.Pm)

A new series of ion-pair complexes [Mo(dtc)4][Ln(dtc)4] (Ln=La-Er, exp. Pm) were synthesized from MoCl5, LnCl3 and Nadtc in anhydrous methanol. The crystal structures of the four complexes, [Mo(dtc)4][Ln(dtc)4] (Ln=Nd, Sm, Ho and Er) have been determined by X-ray diffraction. Spectroscopic properties of all these complexes are also discussed here.     

金属材料分析方法的选择和施行：第五讲 金属材料中钨的测定（续）

此外,尚有二硫酚、邻羟基酚类试剂、酸性三苯甲烷类试剂、偶氮类试剂以及荧光酮类试剂等也都有应用于钨的光度测定的实例。但由于共存元素的干扰以及方法的成熟程度等问题尚未完全得到解决,在金属材料分析中的应用尚不普遍。其中,苯基荧光酮类试剂对钢铁中低含量钨的测定有一定的应用前景,举两例说明:例1:邻氯苯基荧光酮(o-Cl-PF)-CTMAB光度法测定钢及合金中低含量钨[w(W)0.01%~0·50%]。称取试样0.100 0~0.200 0 g,溶于硫酸-磷酸混合酸(H2SO4+H3PO4+H2O=3+10+12)10 mL中,滴加浓硝酸约1 mL氧化,蒸发至冒白烟,冷却,加水溶解盐类后冷…     

Topology evolution and gelation mechanism of agarose gel

Kinetics as well as the evolution of the agarose gel topology is discussed, and the agarose gelation mechanism is identified. Aqueous high melting (HM) agarose solution (0.5% w/v) is used as the model system. It is found that the gelation process can be clearly divided into three stages: induction stage, gelation stage, and pseudoequilibrium stage. The induction stage of the gelation mechanism is identified using an advanced rheological expansion system (ARES, Rheometric Scientific). When a quench rate as large as 30 deg C/min is applied, gelation seems to occur through a nucleation and growth mechanism with a well-defined induction time (time required for the formation of the critical nuclei which enable further growth). The relationship between the induction time and the driving force which is determined by the final setting temperature follows the 3D nucleation model. A schematic representation of the three stages of the gelation mechanism is given based on turbidity and rheological measurements. Aggregation of agarose chains is promoted in the polymer-rich phase and this effect is evident from the increasing mass/length ratio of the fiber bundles upon gelation. Continuously increasing pore size during gelation may be attributed to the coagulation of the local polymer-rich phase in order to achieve the global minimum of the free energy of the gelling system. The gel pore size determined using turbidity measurements has been verified by electrophoretic mobility measurements.     

碳糊电极阳极溶出法测定中药甘草中桑色素

用碳糊电极阳极溶出法测定桑色素的含量。在0.15mol·L-1NH4Cl 氨水缓冲溶液的介质中富集120s,桑色素在+0.10V(vs.SCE)左右出现阳极溶出峰。其峰电流的大小与桑色素的浓度呈线性关系。线性范围为4.00×10-6～1.40×10-5mol·L-1,相关系数为0.9996,检出限可达1.00×10-6mol·L-1,回收率为99.87%～102.01%。此法不用汞电极,灵敏度高,操作方便、快捷,成功地用于甘草提取物中桑色素的测定。     

白菜DNA甲基化水平的反相离子对高效液相色谱法研究

建立了反相离子对液相色谱测定白菜的DNA甲基化水平的方法。采用的色谱柱为HypersilBDSC18柱(200mm×4.0mm,5μm),以pH4.0的甲醇-5mmol·L-1庚烷磺酸钠-三乙胺(10:90:0.2,体积比)的混合液为流动相,UV检测器波长为273nm。通过测定DNA水样所产生的胞嘧啶和甲基胞嘧啶的含量,即可得知DNA甲基化程度。胞嘧啶和甲基胞嘧啶回收率分别为99.6%及103.3%,RSD为3.7%(日内)及5.2%(日间)。     

N-环丙甲基-7α-[(R)-1-羟基-1-甲基-3-(2-噻吩)丙基]-6,14-内乙基桥四氢去甲基蒂巴因(噻诺啡)合成和晶体结构

N-环丙甲基-7α-[(R)-1-羟基-1-甲基-3-(2-噻吩)丙基]-6,14-内乙基桥四氢去甲基蒂巴因(噻诺啡)是阿片受体部分激动剂.噻诺啡经过一步法合成其结构通过单晶X射线衍射分析确证,其结构保持吗啡"T"型主体结构.     

PVC功能膜固相透射光度法测定钯

提出了用PVC功能膜固相透射吸光光度法测定钯的方法。研究发现 ,在pH 3～ 4HOAc NaOAc介质中 ,钯与均匀分布在PVC功能膜上的硫代米氏酮形成疏水性的配合物 ,在自制的固相透射分光光度附件上测定。在 5 2 0nm波长处具有最大吸收 ,钯浓度在 0～ 7.5 μg 10ml范围内 ,A与C有良好的线性关系 ,检出限为 0 .0 15 μg·ml-1,标准偏差为 0 .78%。方法简便、快速、试剂用量少 ,可直接用于矿样中钯的测定