DMF-甲醇体系粘度与核磁共振化学位移的同时关联

提出了一个基于局部组成概念上的核磁共振模型. 利用该模型和以前别人提出的局部组成型粘度方程, 成功地同时关联属于传递性质的粘度数据和属于波谱性质的核磁共振化学位移数据，关联所得到化学位移的平均绝对偏差小于0.0072，粘度的平均绝对偏差小于0.0006 mPa•s，结果表明提出的局部组成模型是合理的.     

Resonance double light scattering method for the determination of proteins with morin-CTMAB

A new determination method of proteins with the limit of determination at nanogram levels is proposed by using a common spectrofluorimeter to detect intensity of resonance double line scattering (RDLS). Proteins including bovine serum albumin (BSA), human serum albumin (HSA) can combine with morin and cetyltrimethylammonium briomide (CTMAB) in the pH range 7.0-8.0 and produce enhanced RDLS signal at lambda(ex)/lambda(em) 305.0/610.0 nm. Optimization conditions for the morin-protein-CTMAB interaction were tested. In the studied system, BSA/CTMAB/morin = 1:2:3. The association constant of morin with BSA is 5.2 x 10(4). Under the optimum conditions, the linear range is 7.5 x 10(-8)-1.0 x 10(-5) g/ml for BSA, 2.5 x 10(-8)-5.0 x 10(-6) g/ml for HSA. The detection limits (S/N = 3) are 66.0 ng/ml for BSA and 23.0 ng/ml for HSA, respectively. Four synthetic samples were analyzed satisfactorily.     

Fluorinated poly(arylene ether ketone)s bearing pentafluorostyrene moieties prepared by a modified polycondensation

The polycondensation of decafluorobenzophenone with hexafluorobisphenol A was modified by the addition of a molecular sieve dehydrating apparatus to the refluxing reaction system. This modification promoted the polymerization and enabled the reactions to be conducted in milder conditions and completed in a shorter time, thereby depressing side reactions such as branching and crosslinking. The resulting fluorinated poly(arylene ether ketone)s (FPAEK) were free of gel particles and possessed the designed molecular weights. This modified procedure was also suitable for introducing crosslinkable pentafluorostyrene (FSt) moieties into the polymers at the chain ends and/or inside the chain with the vinyl group of FSt being pendant. The resulting FSt containing fluorinated poly(arylene ether ketone)s (FPAEK‐FSt) can then be thermally crosslinked at 100 °C in the presence of 1% benzoyl peroxide (BPO) or at 250 °C without any initiator. The glass‐transition temperatures (T_g's) of FPAEK increased with increasing molecular weight and leveled off at about 147 °C for the polymer with a number‐average molecular weight of 18,600 Da, whereas the values were not apparently affected by the addition of FSt units. However, crosslinking of the FPAEK‐FSt resulted in an approximate 30 °C increase of the T_g. Spin‐coating FPAEK‐FSt onto silicon wafers followed by crosslinking gave films with excellent thermal stability, physical strength, and adhesion to the substrate as well as good reproducibility in terms of film preparation and optical properties. The refractive index and birefringence of the films measured at a wavelength of 1.55 μm were 1.502 and 2.5 × 10^?3, respectively. © 2002 Government of Canada. Exclusive worldwide publication rights in the article have been transferred to Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 4205–4216, 2002     

Novel 99mTc labeled σ receptor ligand as a potential tumor imaging agent

A novel ^99mTc labeled complex, [N-[2-((2-oxo-2-(4-(3-phenylpropyl)piperazin-1-yl)ethyl) (2-mercaptoethyl)amino)acetyl]-2-aminoethanethiolato]Technetium(V) oxide (PPPE-MAMA’-^99mTcO) ([ ^99m Tc]-2) has been designed and prepared based on the integrated approach. The corresponding rhenium complex (PPPE-MAMA’-ReO)(Re-2) has been prepared and characterized. In vitro competition binding assays show moderate affinity of Re-2 towards σ₁ and σ₂ receptors with K _i values of 8.67 ± 0.07 and 5.71 ± 1.88 μmol, respectively. Planar images obtained at 0.5 h, 4 h, 20 h after i.v. injection indicate the accumulation of [ ^99m Tc]-2 in MCF-7 human breast tumor bearing mice at 20 h. Furthermore, the accumulation of [ ^99m Tc]-2 has been inhibited at 20 h after co-injection of [ ^99m Tc]-2 plus haloperidol (1 mg/kg). Biodistribution studies of [ ^99m Tc]-2 display an in vivo tumor uptake of 0.14% ± 0.01% ID/g at 24 h post i.v. injection with a tumor/muscle ratio of 6.02 ± 0.87. The above results suggest that [ ^99m Tc]-2, derived from a previously published lead compound, retains certain tumor uptake and affinity for σ receptors. [ ^99m Tc]-2 may be used as a basis for further structural modifications to develop tumor imaging agents with high affinity for σ receptors.     

钇对金属陶瓷力学性能和组织的影响

研究了添加钇对Ｔｉ（Ｃ，Ｎ）基金属瓷力学性能和组织的影响。结果表明，加入适量的钇能提高Ｔｉ（Ｃ，Ｎ）基金属陶瓷的抗变强度和硬度，其原因是由于钇与杂质硫起反应在化合物，净化了陶瓷相－金属相，陶瓷相－陶瓷相界面提高子界面结合强度     

内蒙古牧区蒙、汉族人发铜、锌、铁、锶及钙的X-射线荧光光谱法测定

用X-射线荧光光谱法，测定了387例内蒙古牧区蒙古族、汉族成人和儿童的发中铜(Cu)、锌(Zn)、铁(Fe)、锶(St)及钙(Ca)的含量，对同一地区蒙、汉族成人间，成人及儿童间发中五种元素含量进行了比较分析。结果表明：蒙汉族成人发中Cu，Zn、Fe含量不受种族及饮食习惯的影响，其含量无显著性差异；蒙汉族成人发中Sr和Ca含量存在着相平行的显著差异；牧区儿童发Zn含量与牧区成人发Zn含量差异无显著性意义，提示牧区儿童不缺Zn，可能与多动物性食物有关；牧区儿童发中Cu、Fe、Sr、Ca均显著低于牧区成人、可能与儿童发育旺盛和Zn摄入量高对Cu、Fe吸收发生抑制有关。     

取代乙酸配体对乙炔二聚反应催化剂性能的影响

研究了取代乙酸配体作为Ｎｉｅｕｌａｎ催化剂对乙炔二聚反应性能的影响。结果表明，不同功能结构数目的影响，结果表明，不同功能结构数目的的氨羧配体均使催化剂的选择性提高。乙炔转化率略有下降，巯基乙酸配体的加入，则改变了乙炔二聚反应的机理，得到以乙醛为主的产物。     

钙钛矿型复合氧化物Ca_xSr_（1－x）TiO_3催化剂上的甲烷氧化偶联反应

在固定床反应器上，评价了不同温度下钙钛矿型复合氧化物ＳｒＴｉＯ３和ＣａＴｉＯ３的组成变化对甲烷氧化偶联反应的影响．同时，利用ＸＰＳ和ＣＯ２－ＴＰＤ对催化剂的结构及其氧物种的反应特性进行了表征．结果表明：ＳｒＴｉＯ３和少量Ｃａ掺杂的ＣａｘＳｒｌ－ｘＴｉＯ３有利于在较低温度（９２３Ｋ）下催化反应的活性和选择性，而ＣａＴｉＯ３体系则在高温（１０７３Ｋ）下表现出较好的活性和选择性．钙钛矿型复合氧化物ＳｒＴｉＯ３和ＣａＴｉＯ３组成变化对不同温度下反应活性的影响与ＣＯ２－ＴＰＤ的脱附谱图有很好的平行关系．     

有机磷化合物的质谱研究(Ⅶ)——二氮二磷杂环戊烷衍生物的化学电离质谱

本文报道了七种4.5-二氧代-2-硫代-1,3,2,4-二氮二磷杂环戊烷衍生物的化学电离质谱(CIMS,甲烷为反应气),结果表明:CIMS中准分子离子MH~+为基峰离子;MH~+离子易发生失去H_2S,CO,C_3H_6等小分子的裂解,(M+C_2H_5)~+离子存在再断裂。     

流动注射在线阴离子树脂预富集火焰原子吸收测定痕量铜

研究了以阴离子交换树脂作吸附剂的流动注射在线微柱预富集火焰原子吸收测定铜的新方法。在最佳条件下富集１５０ｓ，富集２３倍，检出限０．２μｇ／Ｌ，ＲＳＤ为１．６％，分析速度２０次／ｈ。天然水样中可能存在的离子不干扰铜的测定。所建立的方法已用于水样中痕量铜的测定。