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991.
YU Yun-wu XING Yan GUO Mei-mei LIU Bai-jun JIANG Zhen-hua Alan G. MacDiarmid Institute College of Chemistry Jilin University Changchun P. R. China 《高等学校化学研究》2011,(3):520-523
A novel type of crosslinkable poly(aryl ether sulfone)(PAES) bearing an allyl pendant(PES-OAllyl) was synthesized by a grafting reaction of hydrophenyl-containing PAES(PES-OH) and allyl bromide. PES-OH was prepared by a demethylation reaction of a methoxyphenylated PAES(PES-OCH3) in the presence of pyridine/hydrochlo- ride. The PES-OCH3 was synthesized by an aromatic nucleophilic substitution of bis(4-chlorophenyl)sulfone and (p-methoxy)phenylhydroquinone. Both DSC and solubility investigation were used to ... 相似文献
992.
HU Xiao-li LIU Sa LIU Shao-pu LIU Zhong-fang SONG Yan-qi . Key Laboratory on Luminescence Real-Time Analysis Ministry of Education School of Chemistry Chemical Engineering Southwest University Chongqing P. R. China . Chongqing Station National Water Quality Monitoring Net of City Water Supply Chongqing 《高等学校化学研究》2011,(2):208-211
In a pH=0.65―1.5 NaAc-HCl medium, methylene blue(MB) reacts with 12-tungstophosphoric acid (TPA) by virtue of electrostatic attraction and hydrophobic force to form a 3:2 ion-association complex. As a result, the intensities of resonance Rayleigh scattering(RRS), second-order scattering(SOS) and frequency doubling scatte- ring(FDS) are enhanced greatly. The maximum scattering wavelengths of RRS, SOS and FDS are located at 316, 647 and 311 nm. The increments of scattering intensity(△I) are directly proportio... 相似文献
993.
CHENG Liang-liang ZHANG Yong SHI Wen-fang CAS Key Laboratory of Soft Matter Chemistry 《高等学校化学研究》2011,27(1):145-149
Dodecyl-benzophenone(DBP) and hexadecoxyl-benzophenone(HDBP) as type II photoinitiators used for radical photopolymerization systems were synthesized by Friedel-Crafts reaction, and characterized by 1H NMR and FTIR spectroscopy. The UV-Vis absorption spectra of DBP and HDBP, propitious to photopolymerization under a commercial mercury UV bulb are centered at 345 and 335 nm, respectively. HDBP has higher extinction coefficient than DBP, but lower photoinitiating efficiency. Their photoinitiating performances... 相似文献
994.
MA Fang WANG FangFang LI ZhiRu WU Di LI ZeSheng & GU FengLong State Key Laboratory of Theoretical Computational Chemistry 《中国科学B辑(英文版)》2011,(3)
Mbius container molecules C64H8,C60N4H4,and C58N6H2 with topological one-sided characteristics were constructed at the first time by imitating natural trumpet shells.The structure is an open cage with an inner hexagonal bridge.The bridge joints the outer and inner surfaces of the cage to form a new one-sided Mbius structure.The optimized structures of the three molecules in the singlet(the ground state),triplet and quintet states are obtained using the density functional theory(B3LYP).For the ground state... 相似文献
995.
XU RongZuo & LU Zheng-Rong Departments of Pharmaceutics Pharmaceutical Chemistry University of Utah Salt Lake City Utah USA 《中国科学B辑(英文版)》2011,(2)
Design and development of efficient non-viral gene delivery systems is critical to overcome various barriers for effective intracellular gene delivery.Eight new spermine-based protonatable surfactants were designed,synthesized and evaluated as non-viral pH-sensitive gene carriers.These carriers formed stable complexes with plasmid DNA at an N/P ratio as low as 2.The sizes of the carrier/pDNA nanoparticles (N/P = 12) were in the range of 90–130 nm,smaller than that of Lipofectamine2000/pDNA nanoparticles.The... 相似文献
996.
SUN ZhiQiang & YANG Bai State Key Laboratory of Supramolecular Structure Materials College of Chemistry Jilin University Changchun China Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun China 《中国科学B辑(英文版)》2011,(2)
With the development of science and technology,ordered microstructures with special functions have aroused intense research interest.These functional microstructures have been widely used in fields of microelectronic devices,micro-reactors,biochemical sensors and optical devices,etc.This paper summaries our work on preparation and application of microscopic patterned surfaces with ordered microstructures,and looks into the future development of this field. 相似文献
997.
DOU Chu ong LI Di ZHANG HongYu GAO HongZe ZHANG JingYing & WANG Yue State Key Laboratory of Supramolecular Structure Materials College of Chemistry Jilin University Changchun China Fundamental Department Chinese People's Armed Police Force Academy Langfang China 《中国科学B辑(英文版)》2011,(4)
A series of cholesterol-appended quinacridone (QA) derivatives 1a-1d have been synthesized,in which 1b and 1c could form stable organogels in a wide range of organic solvents upon ultrasound irradiation.Field emission scanning electronic microscope (FESEM) and transmission electron microscopy (TEM) of xerogels or precipitates indicated that 1b and 1c formed 1D fibrous nanostructure,while 1a assembled into 3D flower-like microstructures.The ultrasound-induced organogel process was characterized by kinetic UV... 相似文献
998.
ZHANG BinTian DU Xin JIA SuPing HE JunHui & GUO LiangHong State Key Laboratory of Environmental Chemistry Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing China Functional Nanomaterials Laboratory Key Laboratory of Organic Optoelectronic Functional Materials Molecular Engineering Technical Institute of Physics Chemistry Beijing China 《中国科学B辑(英文版)》2011,(8)
Nanomaterials have been used increasingly in a wide variety of applications, and some of them have shown toxic effects on experimental animals and cells. In this study, a previously established photoelectrochemical DNA sensor was employed to rapidly detect DNA damage induced by polystyrene nanosphere (PSNS) suspensions. In the sensor, a double-stranded DNA film was assembled on a semiconductor electrode, and a DNA intercalator, Ru(bpy)2(dppz)2+ (bpy = 2,2'-bipyridine, dppz = dipyrido[3,2-a:2',3'-c]phenazine... 相似文献
999.
ZHANG Yu HUANG Yu ZHANG Ji ZHANG DaWei LIU JunLiang LIU Qiang LIN HongHui & YU XiaoQi Key Laboratory of Green Chemistry Technology Ministry of Education College of Chemistry Sichuan University Chengdu China Key Laboratory of Bio-resources Eco-environment College of Life Sciences China 《中国科学B辑(英文版)》2011,(1)
Two dinucleotide PNA-cyclen copper(II) complexes with α-PNA (P1) and classical PNA (P2) backbones were synthesized and characterized.The interactions between title complexes and DNA were investigated under physiological conditions.Fluorescence studies indicate that the binding ability of complex P1 to CT-DNA is as twice as that of P2.DNA melting experiments were also carried out and the results show that ΔTm caused by P1 is higher than that caused by P2.Agarose gel electrophoresis experiments demonstrate th... 相似文献
1000.
Corrosion inhibition and mechanism of mild steel in hydrochloric acid by ceftriaxone and amoxicillin
PANG XueHui GONG Min ZHANG YuXuan WEI Qin & HOU BaoRong Institute of Oceanology Chinese Academy of sciences Qingdao China College of Materials Chemical Engineering Sichuan University of Science & Engineering Zigong China School of Chemistry Engineering University of Jinan Jinan China 《中国科学B辑(英文版)》2011,(9)
Corrosion inhibition of mild steel in 1 mol/L HCl by amoxicillin and ceftriaxone in the concentration range of 1.00×10-5-1.00×10-2 mol/L has been studied using weight loss,electrochemical potentiodynamic polarization,electrochemical impedance spectroscopy(EIS),scanning electron microscopy(SEM) and quantum chemistry tests at 298 K.The weight loss experiment showed that the inhibition efficiency increased with amoxicillin and ceftriaxone concentrations to attain the maximums of 80.3% and 94.1%,respectively at... 相似文献