掺Eu~(3+)、Tb~(3+)或Ce~(3+)的InBO_3的合成与光谱

采用固相反应法合成了InBO_3:Re(Re=Eu,Tb,Ce),研究了InBO_3基质中稀土离子的光谱特性,观察到电荷迁移带位于255 nm附近,Eu~(3+)离子在InBO_3 中产生极强的~5D_0→~7F_1 的跃迁表明Eu~(3+)离子在该基质中占据对称性格位。Tb~(3+)的4f-5d 允许跃迁位于240 nm附近,而4f-5d 禁戒跃迁位于267 nm附近,Tb~(3+)离子呈现出极强的~5D_4→~7F_5 发射。Ce~(3+)离子在InBO_3 中不发光。

用于高预倾角液晶显示器件新取向材料

研制一种新型的能够引起18°高预倾角的取向材料──聚酰亚胺（PI）YB29．探讨预倾角对固化温度、固化时间、摩擦强度的依赖关系；同时研究这种材料的红外吸收光谱、电子能谱及240°扭曲的液晶盒的电光特性.

Hydrothermal synthesis and lanthanide doping of complex fluorides, LiYF4, KYF4 and BaBeF4 under mild conditions

The complex fluorides LiYF4, KYF4, BaBeF4 and AYF(4)Eu(x) (A = Li, K) are hydrothermally synthesized at 140-240 degrees C and characterized by powder X-ray diffraction, thermogravimetric analysis, IR spectroscopy, scanning electron microscopy and luminescence measurements.

Lithium ion conducting polymer electrolytes based on alternating maleic anhydride copolymer with oligo-oxyethylene side chains

A comb polymer with oligo-oxyethylene side chains of the type -(CH2CB2O)(12)CH3 was prepared from methyl vinyl ether/maleic anhydride copolymer and poly (ethylene glycol) methyl ether. The polymer can dissolve LiClO4 salt to form homogeneous amorphous polymer electrolyte. The ac ion conduction was measured using the complex impedance method, and conductivities were investigated as functions of temperatures and salt concentration. The complexes were first found to have two classes of glass transition which increase with increasing salt content, The optimum conductivity attained at 25 degrees C is in the order of 5.50 x 10(-6)Scm(-1). IR spectroscopy was used to study the cation-polymer interaction.

Hydrothermal synthesis of the complex fluorides LiBaF3 and KMgF3 with perovskite structures under mild conditions

The complex fluorides, LiBaF3 and KMgF3; which are isostructural with perovskite phases, are hydrothermally synthesized at 120-240 degrees C and characterized by powder X-ray diffraction, thermogravimetric analysis, IR spectroscopy and scanning electron microscopy.

STM investigation of HOPG superperiodic features caused by electrochemical pretreatment

The surface topography of highly oriented pyrolytic graphite (HOPG) which has been subjected to anodized treatment at a low potential (less positive) has been exhaustively studied using scanning tunneling microscopy (STM). Characterization of graphite surface has revealed that a small percentage of the surface (5%-10%) shows superperiodic features. In this case, the typical topographical features are triangular networks with the observed periodicities in the plane ranging from approximately 26 to 240 nm with peak-to-peak amplitudes out of the plane extending from 7 to 35 Angstrom. We show that this triangular network can be attributed to the injection of electrolyte and solvent in the earliest stages of oxidation of the basal HOPG electrode surface. A simple model is proposed to explain this phenomenon.

THE IZOD IMPACT FRACTURE-BEHAVIOR OF PHENOLPHTHALEIN POLY(ETHER KETONE)

The Izod impact fracture behaviour of notched specimens of phenolphthalein poly(ether ketone) (PEK-C) has been studied over a temperature range from room temperature to 240 degrees C by using an instrumented impact tester. The temperature dependence of the maximum load, total impact energy, initiation energy, propagation energy, ductility index (DI) and the relationships between these parameters and the relaxation processes have been investigated.

CHOLESTEROL SENSOR-BASED ON ELECTRODEPOSITION OF CATALYTIC PALLADIUM PARTICLES

A layer of palladium particles was electrodeposited on a glassy carbon electrode. The dispersed Pd particles resulted in a large decrease in overvoltage for the electrochemical oxidation of H2O2 down to +0.4 V vs. Ag/AgCl, based on which a new kind of cholesterol sensor was fabricated. Cholesterol oxidase was immobilized on the Pd-dispersed electrode by cross-linking with glutaraldehyde and a layer of poly(o-phenylenediamine) (PPD) film was electropolymerized on the enzyme layer. The sensor shows a linear response in the concentration range 0.05-4.50 mmol l-1 with a rapid response of less than 20 s. The polymer film can prevent interference from uric acid and ascorbic acid and also increases the thermal stability of the sensor. The sensor can be used for 200 assays without an obvious decrease in activity.

LUMINESCENCE OF BI(3+) AND THE ENERGY-TRANSFER FROM BI(3+) TO R(3+) (R=EU,DY,SM,TB) IN ALKALINE-EARTH BORATES

At room temperature, the Bi3+ ion shows broad band characters of its luminescence in Ca2B2O5, M3B2O6 ( M=Ca,Sr ) and SrB4O7. The maxima of the Bi3+ S-1(0)-->P-3(1) absorption bands are located in the range of 240-300nm, but the energy variation of the corresponding P-3(1)-->S-1(0) emissions is very large. The maxima of these emission bands change from 350nm in Ca3B2O6;Bi3+ to 586nm in SrB4O7:Bi3+. The Stokes shift of the Bi3+ luminescence increases from 6118 cm-1, in Ca2B2O5:Bi3+, to 24439 cm-1, in SrB4O7:Bi3+. The emission intensity of the Bi3+ luminescence increases with the decreasing Stokes shift. It has been found that in Ca2B2O5, the Bi3+ ion could transfer its excitation energy to the R3+ ions ( R=Eu, Dy, Sm, Tb ) , but in, Ca3B2O6 and Sr3B2O6, only Bi3+-->Eu3+ was observed. No energy transfer from Bi3+ to R3+ was detected in SrB4O7.

STUDIES ON RADIATION-INDUCED LOSS OF WEIGHT OF A COPOLYMER OF TETRAFLUOROETHYLENE AND HEXAFLUOROPROPYLENE

The radiation-induced loss of weight of F-46 was found to be proportional to irradiation dose and affected markedly by irradiation temperature.

酞菁铜衍生物LB膜/N-si光伏电池的研究

报道了采用新型酞菁铜衍生物:三特戊基苯氧基对羧基苯氧基酞菁铜(ttc～CuPc)制备LB膜ttc-CuPc/硬脂酸(C_(18))/n-Si光伏电池的结果。测量了电池的光照I—V、暗I—V和光谱响应等特性。在辐照度为100mW/cm~2AMC混合光照射下电池的I_(sc)为240μA/cm~2,V_(oc)为0.33V,观察到反常二极管整流效应并进行了讨论。

THE COMPOSITIONS AND STRUCTURES OF SOME COMPOUNDS IN THE SYSTEM CA-SR-CU-O

The system of Ca-Sr-Cu-O have been investigated. Two new compounds with compositions Sr3Cu5O8+alpha and CaSrCu3O5+alpha have been discovered. Both are orthorhombic with a = 6.489, b = 11.280, c = 12.240 angstrom for CaSrCu3O5+alpha and a = 3.950, b = 11.479, c = 13.420 angstrom for Sr3Cu5O8+alpha. The X-ray powder data for CaSrCu3O5+alpha, Sr3Cu5O8+alpha, Sr2CuO3 and SrCuO2 are presented. The oxidation state of Cu ion and oxygen contents are analyzed by iodometric titration. Sr0.5Ca0.5CuO2 that has a similar structure with SrCuO2 has been found and its X-ray data are presented also.

甲苯胺蓝化学修饰电极流动注射分析测定肌红蛋白和血红蛋白

血色素蛋白分子空间结构庞大,电活性中心不易暴露;同时这些分子在电极上吸附强烈而造成电极的钝化,因而其在普通电极上的电子转移速率很低,得不到有效的电流响应。将吩噻嗪染料亚甲蓝等媒介体吸附到