Photoluminescent properties of dye-doped poly(N-vinyleabzole) (PVK) in microcavity

A surface emitting microcavity was formed by sandwiching a polymer film containing poly(N-vinyleabzole) (PVK). 8-hydroxyquinoline aluminium (Alq(3)) and 4-(Dicyanome thylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-Pyran(DCM) between a distributed Bragg reflector (DBR) with a reflectivity of 99% and a silver film. The sample was optically pumped with 250 ps pulses at 2 Hz repetition rate by a 355 nm line of the third harmonic of a mode-lock Nd:YAG laser. The lasing phenomenon was observed in DCM-doped PVK microcavity. The full width at half maximum (FWHM) was 3 nm with the peak wavelength at 602 nm. The threshold energy for lasing was estimated to be about 3 mu J. (C) 2000 Elsevier Science S.A. All rights reserved.

Studies on insoluble species of Gd (III) in human blood plasma by computer simulation

The insoluble species of Gd (III) in human blood plasma were investigated by computer simulation. The distribution of the Gd (I) species was obtained. It was found that most of the Gd (III) ions were bound to phosphate to form precipitate GdPO4 at the concentration of 1. 000 x 10(-7) mol/L and when the concentration of the Gd (III) increased to 3. 750 x 10(-4) mol/L, in excess of the concentration of phosphate, the Gd (III) ions were bound to carbonate to form another kind of precipitate, Gd-2 (CO3)(3).

Amplification of antigen-antibody interactions based on biotin labeled protein-streptavidin network complex using impedance spectroscopy

Antibody was covalently immobilized by amine coupling method to gold surfaces modified with a self-assembled monolayer of thioctic acid. The electrochemical measurements of cyclic voltammetry and impedance spectroscopy showed that the hexacyanoferrate redox reactions on the gold surface were blocked due to the procedures of self-assembly of thioctic acid and antibody immobilization. The binding of a specific antigen to antibody recognition layer could be detected by measurements of the impedance change. A new amplification strategy was introduced for improving the sensitivity of impedance measurements using biotin labeled protein- streptavidin network complex. This amplification strategy is based on the construction of a molecular complex between streptavidin and biotin labeled protein. This complex can be formed in a cross-linking network of molecules so that the amplification of response signal will be realized due to the big molecular size of complex. The results show that this amplification strategy causes dramatic improvement of the detection sensitivity of hIgG and has good correlation for detection of hIgG in the range of 2-10 mug/ml. (C) 2001 Elsevier Science B.V. All rights reserved.

Studies on blends of LLDPE and ethylene-methacrylic acid random copolymer

Blends of linear low-density polyethylene (LLDPE) and poly(ethylene-co-methacrylic acid) (EMA) random copolymer were studied by differential scanning calorimetry (DSC), wide-angle X-ray diffraction (WAXD), and excimer fluorescence. In binary blends, crystallization of EMA was studied, and no modification of crystal structure was detected. In excimer fluorescence measurements, emission intensities of blends of EMA and naphthalene-labeled LLDPE were measured. The ratio of the excimer emission intensity (I-D) to the emission intensity of the isolated "monomer" (I-M) decreases upon addition of EMA, indicating that PE segments of EMA interpenetrate into the amorphous phase of LLDPE. (C) 1998 Published by Elsevier Science Ltd,. All rights reserved.

BaCe_(0.8)Ln_(0.2)O_(2.9)(Ln=Gd,Sm,Eu)固体电解质的低温制备及其燃料电池性质

利用溶胶 凝胶法低温合成了BaCe0 .8Ln0 .2 O2 .9(Ln =Gd ,Sm ,Eu)固体电解质 ,X射线粉末衍射表明 90 0℃即形成正交钙钛矿结构 ,较高温固相反应合成温度降低了约 6 0 0℃ .测定了样品的阻抗谱和电导率 ,研究了其导电机理 ,溶胶 凝胶法合成可减小或消除固体电解质的晶界电阻 ,80 0℃时BaCe0 .8Gd0 .2 O2 .9的σ =7.87× 10 -2S·cm-1,以它为电解质的氢氧燃料电池开路电压接近 1V ,最大输出功率密度为 30mW·cm-2 .

甲烷与二氧化碳重整制取合成气反应的研究ⅢSr(La)NiAl11O19积炭动力学

用热重（ＴＧＡ）方法，研究了ＬａＮｉＡｌ１１Ｏ１９和ＳｒＮｉＡｌ１１Ｏ１９催化剂上甲烷与二氧化碳重整反应的积炭动力学．实验结果表明，甲烷裂解是ＣＨ４＋ＣＯ２反应中主要的积炭反应；甲烷与二氧化碳重整反应的积炭速率随反应温度升高而增大，但其衰减速度也较快；ＣＨ４＋ＣＯ２反应的积炭速率相对甲烷分压的反应级数是１，相对二氧化碳分压的反应级数是－０．５；在ＳｒＮｉＡｌ１１Ｏ１９中掺入Ｌａ３＋离子，提高了催化剂上甲烷裂解反应的活化能，降低了ＣＯ２消炭反应的活化能，从而提高了催化剂的抗积炭能力.

氢化丁腈橡胶的性能

氢化丁腈橡胶（ＨＮＢＲ）由ＮＢＲ主链上的双键被氢化还原成饱和键而制成。它不仅保持ＮＢＲ特有的耐介质性和耐磨性，而且还具有优良的耐热、耐候、耐氧等性能，能够满足油田及汽车工业不断提出的新的苛刻的使用要求。ＨＮＢＲ自１９８４年由德国Ｂａｙｅｒ公司和日本瑞…

交联极性固定相非晶硅膜改性弹性玻璃毛细管气相色谱柱的研制

交联FFAP极性固定相非晶硅膜改性弹性玻璃毛细管气相色谱柱是一种新柱型，具有技效高、化学惰性好、稳定性好、抗溶剂、抗腐蚀和耐高温等性能，本文报道了该新型色谱柱的制备及其性能研究。

DETERMINATION OF AMINOPYRINE AND ITS METABOLITE BY CAPILLARY ELECTROPHORESIS ELECTROCHEMICAL DETECTION

An electrochemical pretreatment regime for a cylindrical carbon fibre microelectrode was optimized for the determination of aminopyrine (AM) and its metabolite 4-aminoantipyrine (AAN) by capillary electrophoresis (CE)-electrochemical detection (ED). Under optimized conditions, a response of high sensitivity and stability was obtained for AM and AAN at a detection voltage as low as 0.9 V following CE-ED, by which AM and AAN were separated satisfactorily. The calibration graph was linear over three orders of magnitude and the limits of detection for AM and AAN were in the femtomole range.

含二羟基二苯酮的系列热致液晶共聚酯的合成和表征──Ⅲ．含4，4＇－二羟基二苯砜结构的共聚酯

含二羟基二苯酮的系列热致液晶共聚酯的合成和表征──Ⅲ．含４，４＇－二羟基二苯砜结构的共聚酯董德文，池振国，倪玉山，丁孟贤（中国科学院长春应用化学研究所长春１３００２２）陈玉（东北师范大学分析测试中心长春１３００２４）关键词４，４＇－二羟基二苯酮，热致...

Dawson结构杂多阴离子~（183）W NMR谱的研究──“极位”W原子~（183）W NMR谱化学位移值的预测

本文研究了Ｄａｗｓｏｎ结构取代原子数与相应的１８３ＷＮＭＲ谱中“极位’Ｗ原子的化学位移值间的关系，预测广α－１，２－［Ｐ２Ｗ１６Ｎｂ２Ｏ６２］８－α－１－２，３－［Ｐ２Ｗ１５ＭｏＮｂ２Ｏ６２］８－“极位”Ｗ原子１８３ＷＮＭＲ谱化学位移们，结果α－１，２－［Ｐ２Ｗ１６Ｎｂ２Ｏ６２］８－中与取代Ｎｂ相连“极位”Ｗ原子的化学位移值为－８８ｐｐｍ，与取代Ｎｂ书对称“极位”Ｗ原了的化学位移值为－１４４．７ｐｐｍ，与取代Ｎｂ不对称“极位”Ｗ原子的化学位移值为－１３０．５ｐｐｍ，α－１－２，３－［Ｐ２Ｗ１５ＭｏＮｂ２Ｏ６２］８－中与取代Ｍｏ对称“极位”Ｗ原子的化学位移值为－１３４．７ｐｐｍ，与取代Ｎｂ对称“极位”Ｗ原子的化学位移值为－１４５．６ｐｐｍ．

GAMMA-RADIATION DAMAGE TO POLYAMIDE-1010 CRYSTAL-STRUCTURE

Radiation effects on polyamide-1010 specimens having various states of aggregation were studied using wide angle X-ray diffraction, electron spin resonance, calorific and sol measurement techniques. Experimental results indicated that chain crosslinking

FRACTIONATED CRYSTALLIZATION IN POLYOLEFINS-NYLON-6 BLENDS

The crystallization behavior of polyolefins-nylon 6 polymer blends was studied by differential scanning calorimetry (DSC) measurements. In these blends, the crystallization of the minor component often starts with distinctly deeper supercooling than that

非加热气敏元件气敏机理研究

研制成ａ－Ｆｅ２Ｏ３和ＣｅＯ２作加热气敏元件，指出气敏元件的比表面积越大（可达１４２ｍ２／ｇ），吸附的ＯＨ－（Ｏ２－）越多，气敏性能越好．研究了温度与阻值变化关系以及表面吸附氧的状态与温度关系，指出了表面吸附氧主要以Ｏ－和Ｏ２－形式存在．气敏元件对氢等还原气体敏感．对ＣＯ不敏感．

RADIATION EFFECTS ON POLY(VINYLIDENE FLUORIDE)

Melt-crystallized poly(vinylidene fluoride)s (PVF2) with different crystallization histories were irradiated with gamma-rays within the range of irradiation doses 0-83 Mrad. The effects on the crystalline structure and mechanical properties have been measured, compared, and discussed. The degree of crystallinity of the samples was found to increase with radiation dose. The differential scanning calorimeter scans of the quenched samples indicate that there are two melting peaks, and that the area of the lower temperature peak increases while the area of higher temperature peak decreases with increasing dose. Yield stress and breaking stress for all samples are not significantly affected by irradiation but elongation at break is.