Intramolecular charge transfer in pyrromethene laser dyes: photophysical behaviour of PM650.

Absorption and fluorescence (steady-state and time-correlated) techniques are used to study the photophysical characteristics of the pyrromethene 650 (PM650) dye. The presence of the cyano group at the 8 position considerably shifts the absorption and fluorescence bands to lower energies with respect to other related pyrromethene dyes; this is attributed to the strong electron-acceptor character of the cyano group, as is theoretically confirmed by quantum mechanical methods. The fluorescence properties of PM650 are intensively solvent-dependent. The fluorescence band is shifted to lower energies in polar/protic solutions, and the evolution of the corresponding wavelength with the solvent is analysed by a multicomponent linear regression. The fluorescence quantum yield and the lifetime strongly decrease in polar/protic solvents, which can be ascribed to an extra nonradiative deactivation, via an intramolecular charge-transfer state (ICT state), favoured in polar media.     

Regioselective N-vinylation of cyclic thionocarbamates through a vinyl bis-sulfone methodology

A vinyl bis-sulfone Michael type approach towards heteroatom vinylation was applied on nitrogen derivatives. Cyclic thionocarbamates--mainly 1,3-oxazolidine-2-thiones--were converted into their N-vinyl counterparts; the procedure proved particularly efficient in the case of carbohydrate-derived complex structures.     

Dendritic nanowire ultraviolet laser array

Self-organized dendritic crystal growth is explored to assemble uniform semiconductor nanowires into highly ordered one-dimensional microscale arrays that resemble comb structures. The individual ZnO nanowires have uniform diameters ranging from 10 to 300 nm. They are evenly spaced on a stem with a regular periodicity of 0.1-2 micrometer. Under optical excitation, each individual ZnO nanowire serves as a Fabry-Perot optical cavity, and together they form a highly ordered nanowire ultraviolet laser array.     

Methodological modifications on quantification of phosphatidylethanol in blood from humans abusing alcohol,using high-performance liquid chromatography and evaporative light scattering detection

Background  

Phosphatidylethanol (PEth) is an abnormal phospholipid formed slowly in cell membranes by a transphosphatidylation reaction from phosphatidylcholine in the presence of ethanol and catalyzed by the enzyme phospholipase D. PEth in blood is a promising new marker of ethanol abuse depending on the high specificity and sensitivity of this marker. None of the biological markers used in clinical routine at the present time are sensitive and specific enough for the diagnosis of alcohol abuse.     

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.     

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.     

笼形聚偕胺肟树脂的研究HX／ACAO树脂吸附贵金属

氢卤酸、硝酸、硫酸、磷酸和硼酸处理的笼形聚偕胺肟树脂（ＨＸ／Ａ－ＣＡＯ）对Ａｇ＋和等贵金属离子的吸附能力按如下顺序：ＰｄＣｌ４２－：Ｈ３ＢＯ３／ＡＣＡＯ＞ＢＣＡＯ＞Ｈ３ＰＯ４／ＡＣＡＯ＞ＨＩ／ＡＣＡＯ＞Ｈ２ＳＯ４／ＡＣＡＯ＞ＨＣｌ／ＡＣＡＯ＞ＨＮＯ３／ＡＣＡＯ＞ＨＦ／ＡＣＡＯ．ＩｒＣｌ６２－：ＢＣＡＯ＞Ｈ３ＰＯ４／ＡＣＡＯ＞Ｈ３ＢＯ３／ＡＣＡＯ＞ＨＣｌ／ＡＣＡＯ＞ＨＦ／ＡＣＡＯ＞ＨＩ／ＡＣＡＯ＞Ｈ２ＳＯ４／ＡＣＡＯ≥ＨＮＯ３／ＡＣＡＯ．ＰｔＣｌ６２：ＢＣＡＯ＞Ｈ３ＢＯ３／ＡＣＡＯ＞Ｈ２ＳＯ４／ＡＣＡＯ＞ＨＮＯ３／ＡＣＡＯ＞ＨＣｌ／ＡＣＡＯ＞ＨＦ／ＡＣＡＯ＞Ｈ３ＰＯ４／ＡＣＡＯ＞ＨＩ／ＡＣＡＯ．Ａｇ＋：ＢＣＡＯ＞Ｈ３ＢＯ３／ＡＣＡＯ＞ＨＩ／ＡＣＡＯ＞Ｈ２ＳＯ４／ＡＣＡＯ＞ＨＦ／ＡＣＡＯ＞ＨＣｌ／ＡＣＡＯ＞Ｈ３ＰＯ４／ＡＣＡＯ＞ＨＮＯ３／ＡＣＡＯ．ＡｕＣｌ４－：ＢＣＡＯ＞Ｈ３ＢＯ３＞Ｈ３ＰＯ４／ＡＣＡＯ＞ＨＦ／ＡＣＡＯ＞ＨＣｌ／Ａ－ＣＡＯ＞Ｈ２ＳＯ４／ＡＣＡＯ＞ＨＩ／ＡＣＡＯ＞ＨＮＯ３／Ａ－ＣＡＯ．研究了Ｈ３ＢＯ３／ＡＣＡＯ树脂对Ａｇ＋和离子的吸附动力学，讨论了吸附机理．     

Determination of Diffusion Coefficients for Binary Nonelectrolyte Mixtures. A Free-Volume Predictive Approach

A diaphragm cell has been used to measure mutual diffusion coefficients at 25°C for four binary nonelectrolyte mixtures: ethylbenzene + n-hexane, carbon tetrachloride + ethylbenzene, cyclohexane + p-xylene, and 1,2-dichloroethane + cyclohexane. A free-volume predictive approach for binary mutual diffusion coefficients was developed and tested. Only infinite dilution diffusion coefficients, some readily available pure substance data, and UNIFAC group contribution parameters are used in the model. No binary equilibrium thermodynamic information is required. For 73 binary systems with an overall average absolute deviation of 5.2%, it has been shown that the developed method is better than two commonly available reference methods for the prediction of liquid diffusion coefficients.     

单核零价过渡金属配合物的研究——Ⅱ.含有π-键合醌及双齿氮配体的混配零价钯配合物的合成与表征

本工作合成了一系列十个新的零价钯混配配合物,并对这些配合物进行了表征.研究了配体的立体效应和电子效应的差别,讨论了配体间的相互作用.一.配合物的合成与组成据文献合成dba(PhCH=CHCOCH=CHPh)和Pd_2(dba)_3(CHCl_3).其余试剂及溶剂均为市售商品,用前经无水无氧处理.     

A Study of the Silylation of 1,8-Dihydroxynaphthalene

Twelve compounds each having a six membered Si-contained heterocycle, have been successfully synthesized. Of these eleven compounds have never been reported in the literature. The structures were confirmed by Spectral analysis and elementary analysis. The stability and properties of these compounds is also discussed.