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Determination of Proteins by Measuring Total Internal-reflected Resonance Light Scattering Signals on Water/Tetrachloromethane Interface with Evans Blue and Cetyltrimethylammonium Bromide

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Chemical Research in Chinese Universities 2005年第4期21卷 426-430页

作者： HUANGCheng-zhi FENGPing LIYuan-fang ZHAOHua-wen collegeofchemistryandchemicalengineering SouthwestUniversityChongqing400715P.R.China

A sensitive and selective assay of proteins is proposed based on measuring the total internal-reflected resonance light scattering(TIR-RLS) signals produced on the water/tetrachloromethane(H_2O/CCl_4) interface. In an aqueous medium with pH value in the range of 3.29—3.78, electrostatic attraction occurs between the negatively charged Evans Blue(EB) and positively charged proteins, forming hydrophobic ion associates and resulting in EB-protein adsorption on H_2O/CCl_4 interface. The presence of cetyltrimethylammonium bromide prompts this adsorption, resulting in strongly enhanced TIR-RLS signals. The intensity of the enhanced TIR-RLS at 360—370 nm was found to be proportional to the concentration of proteins. For bovine serum albumin and human serum albumin, the linear range of detection is 0.07—1.2 μg/mL and the limits of detection are 6.68 and 6.30 ng/mL(3σ), respectively, while for lysozyme, the linear range of detection is 0.06—1.0 μg/mL and the limit of detection is 6.0 ng/mL(3σ). The content of the total albumin in a human urine sample could be directly determined by using the standard addition method with a percent recovery of 97.6%—104.1%, and the RSD ranging from 1.9% to 4.2%.

关键词： Total internal-reflected resonance light scattering(TIR-RLS) Protein Evans Blue(EB) Cetyltrimethylammonium bromide(CTMAB)

Fluorescence and cofluorescence enhancement of Tb(Ⅲ) complexes with pyromellitic acid by M (M = Gd, La, Ca, and Sr ions)

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Rare Metals 2004年第1期23卷 32-37页

作者： WANGZhengxiang CHENHong SHUWangen ZHAODongbai ZHOUZhongcheng collegeofchemistryandchemicalengineering.CentralSouthUniversity.Changsha410083 China／KeyLaboratoryofNewMaterialsandTechnologyofChinaNationalPackagingCorporation.ZhuzhouInstituteofTechnologyZhuzhou412008China KeyLaboratoryofNewMaterialsandTechnologyofChinaNationalPackagingCorporation ZhuzhouInstituteofTechnologyZhuzhou412008China collegeofchemistryandchemicalengineering.CentralSouthUniversity Changsha410083China

Fluorescence and cofluorescence properties of Tb(Ⅲ) solid complexes werestudied using pyromellitic acid (PMA) as ligand and fluorescence inert ions as doping elements. Thecofluorescence enhancement, a result of ligand sensitized fluorescence, was observed in Tb(Ⅲ) solidcomplexes doped with fluorescent inert ions La(Ⅲ), Gd(Ⅲ), Ca(Ⅲ), and Sr(Ⅲ). The effect of thetype and content of doping elements on fluorescence enhancement was studied, and optimum conditionswere determined. The results show that Gd (La, Ca, Sr) has clear cofluorescence effect in solidcomplex Tb-M-PMA system, and in present work, rare earth complex fluorescent powder that emitsbright green fluorescence at ultraviolet excitation was obtained, which had potential application asfluorescent anti-counterfeit ink.

关键词： fluorescence enhancement cofluorescence doping elements terbium pyromellitic acid

Ratiometric Fluorescent Receptors for Monosaccharides Based on the Intramolecular Charge Transfer in p-Dialkylaminobenzanilides

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Chinese Journal of Chemistry 2005年第4期23卷 421-426页

作者：刘力宏张晗张煊汪云宝 DepartmentofChemistry theKeyLaboratoryofAnalyticalSciencesoftheMinistryofEducationCollegeofChemistryandChemicalEngineeringXiamenUniversityXiamenFujian361005China

Two dual fluorescent receptors ( 1 and 2 ) for monosaccharides based on 4‐dialkylaminobenzanilides (alkyl=methyl and n ‐butyl) containing boronic acid group at the amido aniline were synthesized and their spectral properties were investigated. These receptors exhibited dual fluorescence with the long‐wavelength band displaying strong solvent‐polarity dependence, indicating the occurrence of the excited‐state intramolecular charge transfer (ICT). With increasing pH value in aqueous solutions, the hybridization of the boron atom changed from sp 2 to sp 3 , inducing a decrease in the total fluorescence quantum yield. The experimental results indicated that the anionic form of the boronate group acted as an electron donor and the benzanilide‐like charge transfer was promoted upon hybridization change. In the presence of monosaccharides, the boronic acid in 1 and 2 changed from neutral to anionic form. The intensity of the locally excited (LE) state emission decreased in the presence of sugars while a slight increase in the intensity at the charge transfer (CT) emission occurred. Based on the change in the CT to LE intensity ratios of 1 and 2 due to sugar binding, ratiometric fluorescent assays for monosaccharide sensing were established.

关键词： dual fluorescence ratiometric receptor intramolecular charge transfer boronic acid monosaccharide

A Possible Reaction Channel from BrONO to BrNO_2

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Chinese Chemical Letters 2002年第11期13卷 1138-1140页

作者： HaiTaoYU XuRiHUANG 等 collegeofchemistryandchemicalengineering HeilongjiangUniversityHarbin150080 StateKeyLaboratoryofTheoreticalandComputationalChemistry InstituteofTheoreticalChemistryJilinUniversit

A possible isomerization channel from BrONO (bromine nitrite) to BrNO2 (nitryl bromide) is predicted by means of MP2 and QCISD(T) (single-point) methods. The channel is a direct bromine abstraction reaction from BrONO molecule by NO2 in which the forward reaction barrier is 89.30 kJ/mol at final UQCISD(T)/6-311+G(2df)//UMP2/6-311G(d) level of theory with zero-point energies included. The result can explain the available experiments very well.

关键词： BrNO2 BrONO isomerization abstraction.

Morphology of Platinum Nanowire Array Electrodepostied Within Anodic Aluminium Oxide Template Characterized by Atomic Force Microscopy

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Chinese Physics Letters 2003年第5期20卷 763-766页

作者： KONGLing-Bin LUMei LIMeng-Ke GUOXin-Yong LIHu-Lin collegeofchemistryandchemicalengineering LanzhouUniversityLanzhou730000 LaboratoryofSpecialFunctionalMaterials HenanUniversityKaifeng475001

Uniform platinum nanowires were synthesized by electrodepositing the platinum under a very low altering current frequency (20Hz) and increasing voltage (5-15V) in the pores of anodic aluminium oxide (AAO) template. Atomic force microscopy observation indicates that the template membranes we obtained have hexagonally close-packed nanochannels. The platinum nanowires have highly ordered arrays after partially dissolving the aluminium oxide membrane. With the increasing dissolving time, the platinum nanowire array collapsed. A concave topography of the aluminium substrate was observed after the aluminium oxide membrane was dissolved completely and the platinum nanowires were released from the template. Platinum nanowires were also characterized by transmission electron microscopy and the phase structure of the Al/AAO/Pt composite was proven by x-ray diffraction.

关键词：原子力显微镜氧化铝薄膜铂 X射线衍射显微结构

Effect of Nano-anatase TiO_2 on Spectral Characterization of PhotosystemⅡParticles from Spinach

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Chemical Research in Chinese Universities 2005年第2期21卷 196-200页

作者： HONGFa-shui YANGPing GAOFeng-qing LIUChao ZHENGLei YANGFan ZHOUJuan CollegeofLifeSciences collegeofchemistryandchemicalengineering SuzhouUniversitySuzhou215006P.R.China

The photosystem Ⅱ(PSⅡ) particles were purified by means of nano-anatase TiO_2 treatment of spinach and studied by spectroscopy. The results show that the electron transport and the oxygen-evolving rate of PSⅡ are accelerated after it has been treated with nano-anatase TiO_2; the UV-Vis absorption spectrum of PSⅡ particles is increased; the red shift of fluorescence emission peak of PSⅡ is 2 nm; the peak intensity is decreased; the PSⅡ signal Ⅱs of low temperature electron paramagnetic resonanace(EPR) spectrum is intensified under light, and the PSⅡ circular dichroism(CD) spectrum is similar to that of control. It is suggested that nano-anatase TiO_2 might bind to the PSⅡ reaction center complex and intensify the function of the PSⅡ electron donor, however, nano-anatase TiO_2 treatment does not change the configuration of the PSⅡ reaction center complex.

关键词： Nano-anatase TiO_2 Spinach PhotosystemⅡ Spectral characterization

Adsorption of Thiourea and Formation of Nickel-thiourea Complexes at Initial Stage of Nickel Deposition

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Chemical Research in Chinese Universities 2004年第6期20卷 757-760页

作者： HUGuang-hui WUHui-huang YANGFang-zu LIUXin-yu StateKeyLaboratoryofPhysicalChemistryofSolidSurfaces CollegeofChemistryandChemicalEngineeringXiamenUniversityXiamen361005P.R.China

The effect of thiourea(TU) on the nickel deposition process was analyzed by means of linear-sweep voltammetry. Raman spectroscopy and infrared reflectance spectroscopy were used to investigate the adsorption of TU and the formation of nickel-TU complexes on copper surface. The experimental results indicate that the nucleation and the preceding conversion step are involved in the deposition of nickel on copper electrodes. TU makes the onset nucleation potential negative due to the formation of nickel-TU complexes, which can accelerate the nickel deposition. Moreover, the S atom in the TU molecule adsorbed on copper surface facilitates the coordination of TU to Ni 2+ . Meanwhile, TU might be adsorbed at a flatter orientation if no Ni 2+ is on the surface, while at a perpendicular orientation when Ni 2+ is coadsorbed.

关键词： Thiourea(TU) Nickel deposition Adsorption Preceding conversion process

Proline Catalyzed Asymmetric Aldol Reaction between Methyl Ketones and 1-Aryl-2,2,2-trifluoroethanones

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Chinese Journal of Chemistry 2005年第5期23卷 584-588页

作者：邱丽华沈宗旋石常青刘艳华张雅文 KeyLaboratoryofOrganicSynthesisofJiangsuProvince CollegeofChemistryandChemicalEngineeringSuzhouUniversitySuzhouJiangsu215006China

Direct asymmetric aldol addition of methyl ketones to 2,2,2‐trifluoro‐1‐phenylethanone and its ring‐substituted derivatives was achieved using L ‐proline as a chiral promoter. Various optically active β‐trifluoromethyl‐β‐hydroxy ketones were obtained in almost quantitative yields with moderate enantioselectivities up to 64 % ee.

关键词： proline aldol addition 1‐aryl‐2,2,2‐trifluoroethanone

A New Highly Oxygenated Eremophilenolide from Ligulariopsis shichuana

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Chinese Chemical Letters 2002年第8期13卷 734-735页

作者： WenShuWANG KunGAO 等 NationalLaboratoryofAppliedOrganicChemistry CollegeofChemistryandChemicalEngineeringLanzhouUniversityLanzhou730000 NationalLaboratoryofAppliedOrganicChemistry CollegeofChemistryandChemicalEngineerin

a new highly oxygenated eremophilenolide was isolated from Ligulariopsis shichuana. Its structure was elucidated by NMR spectroscopic and X-ray diffraction methods.

关键词： Ligulariopsis shichuana compositae sesquiterpene eremophilenolide.