柱前衍生反相高效液相色谱法同时测定植物络合素(PCn)等巯基化合物

介绍一种荧光试剂monobromobimane柱前衍生，反相高效液相色谱一荧光检测测定标准样品和植物组织中植物络合素(PCn)等巯基化合物的方法．结果表明，采用乙腈和0．1％三氟乙酸组成的二元梯度洗脱程序，标准混合液中PCn等5种巯基化合物15min内得到很好的分离．以谷胱甘肽为代表考察方法的精密度，在1．25～160ng/μL浓度范围内与峰高有较好的线性关系，相关系数r^2=0．9999．谷胱甘肽的回收率平均为97．64％，40d内的变异系数平均为2．21％．方法具有快速、灵敏、稳定性好、易于实施、同时测定PCn等多种巯基化合物等优点．通过该方法的应用，首次揭示Cd超积累植物东南景天对CA的超量积累和解毒与PCn无关．     

重组刺桐胰蛋白酶抑制剂的制备及活性鉴定

刺桐胰蛋白酶抑制剂(ETI)是一种Kunitz型胰蛋白酶抑制剂,能够抑制胰蛋白酶及组织型纤溶酶原激活剂的活性,因此ETI可以作为配体与固定相偶联用于亲和层析.利用化学合成及聚合酶链式反应(PCR)的方法获得ETI的编码基因,然后用NdeI/SacI酶切并插入载体pET25b ( )中构建重组表达质粒pET25b ( )/ETI .重组表达质粒转化大肠杆菌BL21(DE3)后,用IPTG诱导使重组ETI(rETI)过量表达形成包涵体.包涵体经过洗涤、复性及CM离子交换柱纯化,每升培养液可获得14 mgrETI ,其纯度超过92 %.活性测定表明,rETI对凝血酶及尿激酶的活性没有抑制作用,但能显著抑制胰蛋白酶、瑞替普酶及纤溶酶的活性,抑制常数Ki分别为5 .14×10-9,9 .4×10-8和2 .08×10-8mol/L.     

水驱油藏含水率及采出程度相似理论研究

为使模拟实验结果更好地应用到油田,为油田开发方案提供理论指导,应用相似定数法导出了水驱油藏相似准则,经相似变换建立了采出程度和含水率相似准则。利用数值模拟方法对各相似准则进行了敏感性分析,利用相似理论函数论对敏感性较强的相似准则进行了研究。结果表明,水驱油藏采出程度及含水率同各相似准则之间满足乘积关系。根据此关系建立了水驱油藏含水率与采出程度的经验关系式。关系式中引入了相渗经验系数以消除模型与原型相渗差异。物理模拟实验与数值模拟结果的对比表明,所建立的经验关系式可以满足油田实际应用。     

新型氮支套索冠醚的合成及络合阳离子的电导特征

以苯氧乙醇为起始剂合成了两种新型氮支套索冠醚：N-苯氧乙基单氮杂-18-冠-6（18CE）与N-苯氧乙基单氮杂-15-冠-5（15CE），通过红外光谱、核磁共振氢谱、紫外光谱和元素分析表征了新冠醚及其中间体的结构，测试了18CE与15CE络合阳离子对溶液电导率的影响。     

WA-IDS： A Distributed Intrusion Detection System Based on Data Mining

Aiming at the shortcomings in intrusion detection systems (IDSs) used in commercial and research fields, we propose the MAIDS system, a distributed intrusion detection system based on data mining. In this model, misuse intrusion detection system (MIDS) and anomaly intrusion detcction system (AIDS) are combined. Data mining is applicd to raise detection performance, and distributed mechanism is employed to increase the scalability and efficiency. Host- and network based mining algorithms employ an improved Bayesian decision theorem that suits for real security environment to minimize the risks incurred by false decisions. We describe the overall architeeture of thc MA-IDS system, and discusss pecific design and implementation issue.     

Hemoglobin Biocatalyst Polymerization of Aniline by UV-vis Spectraphotometry

A biocatalytic route for the synthesis of a water soluble and conducting complex of polyaniline (PAN1)/sodium dodecylsulfate (SDS) is presented. Hemoglobin is used in SDS anion surfactant . The polymerization proceeded quickly to result in a homogeneous emeraldine-colored dispersion of PANI. Absorption spectra of PANI/SDS in the aqueous dispersions at various pH values confirms that the reversibility of dedoping and redoping process of PANI/SDS and shows that the transition from emeraldine salt to emeraldine base form occurred at about pH 10.0-11.0 in this anionic micellar system. PANI/SDS in the organic solutions dedoped initially and redoped after 24h.     

Na(THF)2(μ2-η5-Cp)(η5,η5,η1-Cp3Yb)(THF)]n: The synthesis and X-ray structure of an anionic organolanthanidepolymer formed via self-assembly

Cp2Yb·2THF reacts with CpNa in 1：1 molar ratio in THF at 40℃ for 2 h, and the in situ generated anionic divalent complex NaYbCp3（THF）n reacts further with an excess of CpH at 40℃ for 48h, after work-up, affording the trivalent anionic ytterbium complex[Na（THF）2（μ2-η^5-Cp） （η^5, η^5,η^1-Cp3Yb）（THF）]n：（1） by oxidation reaction of Cp2Yb with CpH. Crystal structure determination reveals that complex 1 has one-dimension polymeric chains of distinct Na（THF）2（μ2-η^5-Cp） （η^5, η^5,η^1-Cp3Yb）（THF） units, which were formed by the coordination of the bridging Cp ligand with Cp3Yb＇THF and Na（THF）2 in η^5,η^5 mode via self-assembly.     

Apoptosis of Spodoptera litura larval hemocytes induced by heavy metal zinc

By adding different amount of zinc into the artificial medium of the insect larvae, the zinc-induced apoptosis of the larvae haemocytes of the herbivorous insect Spodoptera litura Fabricius was investigated with flow cytometer. The results showed that the increase of zinc dose in the artificial feed led to the accumulations of zinc in the larval hemolymph and fat body, and more zinc was accumulated in fat body than in hemolymph. The apoptosis of hemocytes was significantly induced at high zinc concentration （1000 mg·kg^-1） in the insect diet, and the apoptosis rate was 63.63%, which was remarkably higher than that at control and lower concentrations （50--500 mg·kg^-1）. This suggests that the high dose of zinc in the artificial diet of S. litura larvae could induce the apoptosis of the larval hemocytes of S. litura.     

Application of microfluidic chip to realize controllable pH gradient

A kind of PH gradient microfluidic chips through soft-lithography microfabrication for isoelectric focusing (IEF) and high performance liquid chromatography (HPLC) is introduced here. These pH gradient chips have the advantages such as easy fabrication, controllable pH range and precision, isoelectric focusing and separation at the same time, low voltage for isoelectric focusing, and time stable pH gradient. This method has potential application to sample preparation, separation and analysis of microfluidic chips.     

太原市污染物浓度时空分布特征及影响因子分析

对2003年太原市污染物浓度逐日数据和气象资料进行了分析，阐述了污染物浓度的时空变化和污染物浓度与气象条件的关系，为减轻和防止大气污染提供了参考。