STUDIES ON IPE OF POLYACRYLAMIDE INVERSE EMULSION AND MODIFIDE UREA-FORMALDEHYDE RESIN

The selective water plugging agent was prepared by heating the blends of the polyacry-lamide inverse latex, modified urea formaldehyde resin, crosslinking agent and catalysts.The results show that using different types of polymers and additives or changing in theirproportion of the blends, the gelling viscosity, starting point of gelling and other propertiesof the IPN can be controlled.     

Synthesis and electron holography studies of single crystalline nanostructures of clathrate-II phases K(x)Ge136 and Na(x)Si136

Crystalline nanosized particles of clathrate-II phases K(x)Ge(136) and Na(x)Si(136) were obtained from a dispersion of alkali metal tetrelides in ionic liquids based on DTAC/AlCl(3), which were slowly heated to 120-180 °C. The nanoparticles are bullet-shaped with typical dimensions of about 40 nm in width and 140-200 nm in length. Detailed structure investigations using high-resolution transmission electron microscopy (HRTEM) and electron holography reveal the crystallinity and dense morphology of the clathrate nanorods.     

离子交换高效液相色谱法分析质粒pUDKH

采用阴离子交换高效液相色谱法监测重组质粒pUDKH的生产过程和该质粒产物中超螺旋pUDKH的比例。所用的色谱条件为:色谱柱TSK gel DNA NPR (4.6 mm i.d.×75 mm);流动相体系由20 mmol/L Tris HCl(pH 8.8 )和1 mol/L NaCl组成,梯度洗脱方式。分析结果表明:质粒产物中超螺旋pUDKH含量达95%(质量分数)以上时,检测不到残留的核糖核酸(RNA)。高效液相色谱法检测质粒pUDKH产物及其生产过程的灵敏度高、试样用量少,分辨率高。     

流动注射化学发光法测定针剂中呋脲苄青霉素钠

基于碱性介质中,在以铁氰化钾作为催化剂和发光剂,亚铁氰化钾作为发光抑制剂,无过氧化氢时,呋脲苄青霉素钠与鲁米诺能够直接发生化学反应,提出了快速测定呋脲苄青霉素钠的流动注射化学发光法。结果表明:在最佳条件下,呋脲苄青霉素钠浓度在6.5×10-6～8.0×10-4mol.L-1范围内呈线性,方法的检出限(3s/k)为3.3×10-6mol.L-1,对浓度为5.0×10-4mol.L-1的呋脲苄青霉素钠标准溶液连续测定11次,测定值的相对标准偏差为0.9%。以粉针剂样品为基体,用标准加入法检验方法的回收率,测得结果在96.8%～98.3%之间。     

Banach空间上集值测度与模糊数测度的扩张

在Banach空间上,给出集值测度的扩张定理并借助集测度的扩张给出了模糊数测度的扩张定理。     

Dynamic function optimisation with hybridised extremal dynamics

Dynamic function optimisation is an important research area because many real-world problems are inherently dynamic in nature. Over the years, a wide variety of algorithms have been proposed to solve dynamic optimisation problems, and many of these algorithms have used the Moving Peaks (MP) benchmark to test their own capabilities against other approaches. This paper presents a detailed account of our hybridised Extremal Optimisation (EO) approach that has achieved hitherto unsurpassed results on the three standardised scenarios of the MP problem. Several different components are used in the hybrid EO, and it has been shown that a large proportion of the quality of its outstanding performance is due to the local search component. In this paper, the behaviour of the local search algorithms used is analysed, and the roles of other components are discussed. In the concluding remarks, the generalisation ability of this method and its wider applicability are highlighted.     

Mechanisms of the α,α-diphenylprolinol trimethylsilyl ether-catalyzed enantioselective aza-Michael reaction

Depending on the nature of the aza-Michael donor, the C-N bond formation in the α,α-diphenylprolinol trimethylsilyl ether-catalyzed aza-Michael reactions was found to proceed via either (i) an iminol intermediate in a stepwise reaction, or (ii) a concerted reaction. This is contrary to the commonly proposed iminium mechanism for organocatalyst-catalyzed aza-Michael reactions. The iminol intermediate is formed from the reaction between the catalyst and the amine (Michael donor). These proposed mechanisms are able to account for the experimentally observed product enantioselectivity.     

二甲基二烯丙基氯化铵/丙烯酸共聚凝胶的辐射合成与性质研究

采用γ辐射溶液聚合法合成了几种二甲基二烯丙基氯化铵 丙烯酸 (DADMAC AA)共聚凝胶 .实验结果表明单位体积溶液中二组分单体总摩尔数和丙烯酸 (AA)相对含量的增加使共聚凝胶力学强度明显增高 .在两种单体等摩尔比的情况下共聚体的凝胶含量随剂量增加而增加 ,且明显高于聚N ,N′ 二甲基二烯丙基氯化铵 (PolyDADMAC)凝胶 .体系中少量κ 卡拉胶 (KC)的加入可增强共聚凝胶韧性但对凝胶含量和强度影响甚微 .共聚凝胶溶胀性能测定结果表明DADMAC与AA摩尔比为 1∶2时凝胶溶胀比与体系pH值的关系呈现聚两性电解质性质 ,等电点pH值接近 4 5 .这种聚两性电解质性质在对铼Re(Ⅶ )离子浓集中也有所表现     

Study on the novel neutron-to-proton convertor for improving the detection efficiency of a triple GEM based fast neutron detector

A high-efficiency fast neutron detector prototype based on a triple Gas Electron Multiplier(GEM) detector, which, coupled with a novel multi-layered high-density polyethylene(HDPE) as a neutron-to-proton converter for improving the neutron detection efficiency, is introduced and tested with the Am-Be neutron source in the Institute of Modern Physics(IMP) at Lanzhou in the present work. First, the developed triple GEM detector is tested by measuring its effective gain and energy resolution with55 Fe X-ray source to ensure that it has a good performance.The effective gain and obtained energy resolution is 5.0×104and around 19.2%, respectively. Secondly, the novel multi-layered HDPE converter is coupled with the cathode of the triple GEM detector making it a high-efficiency fast neutron detector. Its effective neutron response is four times higher than that of the traditional single-layered conversion technique when the converter layer number is 38.     

松香产品中重质松节油成分的气相色谱/质谱法分析

利用水汽蒸馏提取法富集了松香产品中残留的重质松节油,经气相色谱／质谱联机分析,发现其主要由１９种单萜和倍半萜化合物组成,全部为香味物质（未知物除外）。为提高松香产品的品质和开发利用松香重质松节油提供了依据。