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1.
Meng F. Q. Lu M. K. Yang Z. H. Zeng H. 《Journal of Thermal Analysis and Calorimetry》1998,52(2):609-613
The thermal behavior of two new non-linear optical (NLO) materials, urea-(D) tartaric acid (UDT) and urea-(DL) tartaric acid
(UDLT) were studied by using DSC, TG and TMA. The results show that: 1) The two crystals have different melting points but
similar decomposition temperatures due to the influences of intermolecular forces, which is attributed to the stereo effects
of (D)-tartaric and (DL)-tartaric acid molecules; 2) There was only thermal expansion and no thermal contraction when the
UDT and UDLT crystals were heated; 3) There was no phase transition within the measured temperature range; 4) The thermal
expansion of the UDT and UDLT crystals shows a small anisotropy; 5) The specific heats of UDT and UDLT change linearly with
temperature in the measured temperature range and the value for UDT is 1.321 J g-1 K-1 at 320 K while the specific heat of
UDLT is 1.357 J g-1 K-1 at the same temperature.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Photovoltaic and spectral properties of tetraphenyloporphyrin and metallotetraphenyloporphyrin dyes 总被引:1,自引:0,他引:1
Spectroscopical properties and photocurrent (or photovoltage) of tetraphenyloporphyrins and metallotetraphenyloporphyrins in nematic liquid crystal have been studied. Photoelectric response has been measured in an electrochemical cell made of the semitransparent semiconducting and golden electrodes with porphyrin dyes embedded in liquid crystal. Fluorescence, time-resolved luminescence in microsecond time scale and photoacoustic spectra have also been measured. The competition between radiative, non-radiative processes and charge transfer is discussed. It has been shown that effectivity of porphyrins for photocurrent generation depends on the presence/absence of central metal in the macrocycle of porphyrin skeleton and the kind of metal. The schematic model of the contributions of the dye molecule and semiconducting electrode in the electron transfer process is shown. 相似文献
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注射用生物可降解胰岛素纳米微球的制备 总被引:10,自引:1,他引:10
共聚物;药剂释放体系;注射用生物可降解胰岛素纳米微球的制备 相似文献
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蔡厚德 《南京师大学报(自然科学版)》2006,29(2):73-77
对24名左利手和24名右利手被试在三种注意条件(刺激驱动、注意左耳和注意右耳)下进行双耳分听汉字测验,检查中国人利手与汉字听觉词汇加工大脑两半球功能优势的关系,同时考察被试的注意偏向对优势效应的影响.结果表明:(1)汉语母语左利手被试加工汉字听觉词汇的大脑功能偏侧化组织明显不同于右利手;(2)右利手被试在刺激驱动条件下的右耳(左半球)优势易受注意偏向的调节出现明显波动;(3)注意偏向对左利手被试的影响主要表现为优势的左耳(右半球)成绩的下降与非优势的右耳(左半球)成绩的提高,这暗示汉语母语左利手者可能存在汉字听觉词汇加工的潜在两半球表征. 相似文献
7.
Shah Hussain Cornelia Pezzei Yüksel Güzel Matthias Rainer Christian W. Huck Günther K. Bonn 《Analytica chimica acta》2014
An efficient blood plasma clean-up method was developed, where methanol protein precipitation was applied, followed by zirconium silicate assisted exclusion of residual proteins. A strong binding of zirconium (IV) silicate to the proteins enabled the elimination of remaining proteins after solvent deproteinization through a rapid solid-phase extraction (SPE) procedure. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI/TOF MS) was used for monitoring the proteins during clean-up practice applied to human plasma samples. The proteins were quantified by colorimetric detection using the bicinchoninic acid (BCA) assay. The presented analytical strategy resulted in the depletion of >99.6% proteins from human plasma samples. Furthermore, high-performance liquid chromatography hyphenated to diode-array and electrospray ionization mass spectrometric detection (HPLC–DAD/ESI MS) was applied for qualitative and quantitative analysis of the caffeoylquinic acids (CQAs) and their metabolites in human plasma. The procedure demonstrated high recoveries for the standard compounds spiked at different concentrations. Cynarin and chlorogenic acid were recovered in the range of 81–86% and 78–83%, respectively. Caffeic acid was extracted in the excess of 89–92%, while ferulic acid and dihydroxyhydrocinnamic acid showed a recovery of 87–91% and 92–95%, respectively. The method was partially validated in accordance with FDA-Industry Guidelines for Bioanalytical Method Validation (2001). The presented scheme improves the clean-up efficacy of the methanol deproteinization, significantly reduces the matrix effects and provides a great analytical tool for the isolation of small molecules from human plasma. 相似文献
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研究固态化学反应对合成化学、理论研究以及工业生产都有重要意义,南京大学忻新泉等人在室温或低温温度条件下固相配位反应的合成及机理研究方面做了许多有意义的工作[1,2],为使低温温度固相合成法最终走向应用作了积极贡献。由于固相配位反应的热效应难以直接测定,热化学... 相似文献
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用自行研制的具有恒定温度环境的反应热量计,以mol.L^-1HCl溶液为量热溶剂,测得DL-丙氨酸与醋酸铜固相配位反应焓△rHm=50.852kJ.mol^-1,从而计算了配合物trans-Cu(DL-Ala)2的标准生成焓△fHm=-1015.419kJ.mol^-1。 相似文献
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Alginate, chitosan and gelatin were deposited on the surface of PDL‐LA films via an entrapment method. ATR‐FT‐IR, XPS and contact‐angle analyses revealed the formation of stable thin biomacromolecule layers on the PDL‐LA film, thus enhancing the hydrophilicity of the films. Confocal laser scanning microscopy showed the existence of entrapment areas of approximately 10–20 μm in depth. This simple surface‐treatment method may have the potential for many biomedical applications. 相似文献