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991.
运用毛细管电泳非接触式电导检测方法对4种中枢神经系统用药-盐酸阿扑吗啡、氢溴酸加兰他敏、富马酸喹硫平、氯氮平的分离进行了研究。考察了电泳介质的种类、浓度、分离电压、进样时间对分离效果的影响,在10 mmol/L三羟基氨基甲烷(Tris)-8 mmol/L柠檬酸(Cit)-20%甲醇的运行缓冲液中,激发电压为60V,激发频率为600kHz,4种药物在15 min内得到了分离。4种药物的线性范围分别为0.97~15.6 mg/L;0.97~15.6 mg/L;0.48~15.6 mg/L和0.97~250 mg/L,检测限为0.32,0.32,0.16和0.32 mg/L。 相似文献
992.
993.
Hui Li Peng Tang Yan Zhao Shi‐Xia Liu Yves Aeschi Lijun Deng Jörg Braun Bin Zhao Yunqi Liu Songting Tan Wolfgang Meier Silvio Decurtins 《Journal of polymer science. Part A, Polymer chemistry》2012,50(14):2935-2943
Two well‐defined alternating π‐conjugated polymers containing a soluble electroactive benzo[1,2‐b:4,5‐b′]difuran (BDF) chromophore, poly(BDF‐(9‐phenylcarbazole)) (PBDFC), and poly(BDF‐benzothiadiazole) (PBDFBTD) were synthesized via Sonogashira copolymerizations. Their optical, electrochemical, and field‐effect charge transport properties were characterized and compared with those of the corresponding homopolymer PBDF and random copolymers of the same overall composition. All these polymers cover broad optical absorption ranges from 250 to 750 nm with narrow optical band gaps of 1.78–2.35 eV. Both PBDF and PBDFBTD show ambipolar redox properties with HOMO levels of ?5.38 and ?5.09 eV, respectively. The field‐effect mobility of holes varies from 2.9 × 10?8 cm2 V?1 s?1 in PBDF to 1.0 × 10?5 cm2 V?1 s?1 in PBDFBTD. Bulk heterojunction solar cell devices were fabricated using the polymers as the electron donor and [6,6]‐phenyl‐C61‐butyric acid methyl ester as the electron acceptor, leading to power conversion efficiencies of 0.24–0.57% under air mass 1.5 illumination (100 mW cm?2). These results indicate that their band gaps, molecular electronic energy levels, charge mobilities, and molecular weights are readily tuned by copolymerizing the BDF core with different π‐conjugated units. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
994.
Zhong‐Fu An Chao Zheng Dr. Run‐Feng Chen Jun Yin Jian‐Jian Xiao Hui‐Fang Shi Ye Tao Dr. Yan Qian Prof. Wei Huang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(49):15655-15661
A novel conjugated asymmetric donor–acceptor (CADA) strategy for preventing the redshift in photoluminescence, as well as preserving the merits of donor–acceptor architectures, was proposed and demonstrated for two triazine derivatives, which showed highly efficient, narrow, and blueshifted ultraviolet light emission in solid films along with special aggregation‐induced emission behavior. A mechanism of aggregation‐induced locally excited‐state emission by suppressing the twisted intramolecular charge‐transfer emission for the spectacular optoelectronic phenomena of these CADA molecules was suggested on the basis of both experimental measurements and theoretical calculations. By taking advantage of this special CADA architecture, fluorescent probes based on aggregates of conjugated asymmetric triazines in THF/water for the detection of explosives show superamplified detection of picric acid with high quenching constants (>1.0×107 M ?1) and a low detection limit of 15 ppb. 相似文献
995.
An ideal organic thin film photodetectors (OTFPs) should adopt a hierarchical, multilayer p-type/blend-type/n-type (PIN) structure, with each layer having a specific purpose which could greatly improve the exciton dissociation while guarantee efficient charge transport. However, for the traditional layer-by-layer solution fabrication procedure, the solvent used can induce organic material mixing and molecular disordering between each layer. Hence, such architecture for OTFPs can now only be formed via thermal evaporation. In this paper, a contact-film-transfer method is demonstrated to all-solution processing organic PIN OTFPs on flexible substrates. The fabricated PIN OTFPs exhibit high photoresponse and high stability under continuous mechanical bending. Hence, the method we described here should represent an important step in the development of OTFPs in the future. 相似文献
996.
997.
Xiao‐Lan Wei Rong Han Xiao Hu Li‐Hui Quan Chun‐Yu Liu Qi Chang Yong‐Hong Liao 《Biomedical chromatography : BMC》2013,27(5):636-640
Six esterase inhibitors, namely EDTA·2Na+, NaF, phenylmethanesulfonyl fluoride, dichlorvos, bis‐nitrophenyl phosphate (BNPP) and thenoyltrifluoroacetone, and the mixture of NaF and BNPP, were evaluated for the stabilization of labile benzoate containing zeylenone in rat plasma. The mixture appeared to exhibit the most effectively stabilizing effect with the degraded content of zeylenone decreasing from >60% (in the absence of inhibitors) to <6%. Following the stabilization by the addition of NaF (5 mm ) and BNPP (5 mm ), the analytes in rat plasma were acidified by formic acid and extracted into ethyl acetate at 0°C. After chromatographic separation, the detection of zeylenone was performed on a 3200 Q‐Trap with positive ion electrospray mode, monitoring the ion transition m/z 383.2 → 105.0. The method was validated over the range from 2.68 to 1340 ng/mL with inter‐ and intra‐run precision for the quality control samples being less than 6.8%. The assay accuracy was within 100 ± 7.0%. The validated method was successfully applied to a pharmacokinetic study in rats after the intratracheal administration of zeylenone in free drug or polymeric micellar solutions. The results showed that the pulmonary absorption of zeylenone loaded in micelles was significantly retarded compared with that of free drug solutions. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
998.
建立了浊点萃取-火焰原子吸收光谱法测定4种消食类中草药中Pb含量的方法。以双硫腙为络合剂、非离子表面活性剂聚乙二醇辛基苯基醚(Triton X-100)为萃取剂,采用浊点萃取-火焰原子吸收光谱法联用,测定4种消食类中草药中Pb的含量,探讨溶液p H、表面活性剂用量、络合剂用量、平衡温度、平衡时间、干扰离子等条件对浊点萃取率的影响。最佳条件下,富集倍数为21倍,方法的检出限为0.16μg/L,校准曲线相关系数为0.9995;RSD≤1.7%(n=11),回收率在96.5%~98.1%之间。方法已用于4种消食类中草药中Pb的测定。 相似文献
999.
Shengli Niu Mengqi Liu Chunmei Lu Hui Li Mengjia Huo 《Journal of Thermal Analysis and Calorimetry》2014,115(1):73-79
Potential of carbide slag as transesterification catalyst is validated. Combined with X-ray fluorescence for ingredient determination, X-ray diffraction for textural phase analysis, scanning electron microscope for surface morphology observation and Hammett indicator for basic strength mensuration, thermal event of carbide slag is investigated through thermogravimetric analysis to estimate the potential of this calcium-based industrial waste as transesterification catalyst. Further, kinetic parameters are calculated through model-free method, where the experiments are conducted at temperature heating rates of 5, 10, 15, and 20 K min?1. As for activation energy and reaction order, Vyazovkin method and Avrami theory are respectively mentioned. Meanwhile, catalytic performance of carbide slag is labeled by transesterification efficiency and calcium hydroxide is conditionally mentioned for comparison. In conclusion, potential of carbide slag as transesterification catalyst is adequately validated. 相似文献
1000.
JIA YuPing GUO LiWei LU Wei GUO Yu LIN JingJing ZHU KaiXing CHEN LianLian HUANG QingSong HUANG Jiao LI ZhiLin CHEN XiaoLong 《中国科学:物理学 力学 天文学(英文版)》2014,(5):1004
<正>Addendum to:Science China:Physics,MechanicsAstronomy,2013,56(12):2386–2394doi:10.1007/s11433-013-5348-2The legends of the following Figures should be as follows:Figure 3 AFM morphologies and Raman spectra of a EG on a 2 inch SiC(0001)measured at five representative regions.(a)AFM Morphology reproduced from ref.[14]with permission from Science China Press and Springer publishing,(b)Raman spectra.Figure 6 SEM images of the VAGS.(a)Cross-section image of the VAGS;(b)and(c)are the top view images of the as-grown VAGS and the VAGS after top graphene layer removed reproduced from ref.[16]with permission from Wiley-VCH publishing. 相似文献