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91.
本提出了一种泡沫塑料柱在线分离富集/β-环糊精-十二烷基苯磺酸钠溶液在线洗脱/硫代米蚩酮光度法测定痕量金的新方法。方法的检测出限是3×10^-^8gAu,线性范围是5×10^-^7-8×10^-^6Au,对于1.0μgAu进行11次测定,相对标准偏差小于3.0%。 相似文献
92.
Three novel perylene polyimides (PPIs) containing p‐n diblock units were designed and synthesized for use in dye‐sensitized mesoporous TiO2 solar cells. They all dissolve in m‐cresol and N‐methyl‐2‐pyrrolidone (NMP). Their visible light absorption, electrochemical and photoelectrochemical properties were systematically studied. The polyimides have band gap energies of 2.16, 2.19 and 2.25 eV deduced from ultraviolet–visible absorption spectra, and electron affinity (Ea) and ionization potential (IP) of ?3.93 and 6.10 eV for PPI1, ?3.94 and 6.13 eV for PPI2, ?3.93 and 6.59 eV for PPI3, respectively, deduced from cyclic voltammogram. Experimental data show that introduction of 4,4′‐bisaminetriphenylamine cannot only greatly enhance optic‐electro conversion efficiency, but also enhance the dissolubility which in favorable for making the devices. The relationship of structure and properties of PPI is discussed and the mechanism of photocurrent generation is explained. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
93.
Bai JZ Bardon O Blum I Breakstone A Burnett T Chen GP Chen HF Chen J Chen SJ Chen SM Chen Y Chen YB Chen YQ Cheng BS Cowan RF Cui HC Cui XZ Ding HL Du ZZ Dunwoodie W Fan XL Fang J Fero M Gao CS Gao ML Gao SQ Gao WX Gratton P Gu JH Gu SD Gu WX Gu YF Guo YN Han SW Han Y Harris FA Hatanaka M He J He KR He M Hitlin DG Hu GY Hu HB Hu T Hu XQ Huang DQ Huang YZ Izen JM Jia QP Jiang CH Jin Y Jones L Kang SH Kelsey MH Kim BK Lai YF Lan HB Lang PF Lankford A Li F Li J Li PQ Li Q Li RB 《Physical review D: Particles and fields》1995,52(7):3781-3784
94.
偏最小二乘-速差动力学分光光度法同时测定杀虫剂残杀威和异丙威两组分 总被引:11,自引:0,他引:11
采用速差动力学分光光度法对氨基甲酸脂类杀虫剂残杀威和异丙威进行同时测定,这两种化 的能在碱性条件下水解生成酚盐,进而与对氨基苯酚及高碘酸钾的反应产物醌亚胺发生偶联反应,生成蓝色化合物。反应的速率适中,可用于动力学分析。实验采集了多个时间点下538-700nm间的动力学-吸光度数据,构成量测矩阵,并采用偏最小二乘(PLS)法对量测数据进行解析。本文还对合成样品和环境水样中的残杀威和异丙威含量进行测定,获较好的结果。 相似文献
95.
The exchange of the PPh3 ligand in the complex [1,3-bis(2,6-dimethylphenyl)4,5-dihydroimidazol-2-ylidene](PPh3)(Cl)2Ru=CHPh (7) for a pyridine ligand at ambient temperature leads to the formation of the stable phosphine-free carbene ruthenium complex [1,3-bis(2,6-dimethylphenyl)4,5-dihydroimidazol-2-ylidene](C5H5N)2(Cl)2 Ru=CHPh (8). The resulted ruthenium complex exhibits highly catalytic activity for the cross metathesis of acrylonitrile with various functionalized olefins under mild conditions, and its activity can be further improved by the addition of a Lewis acid such as Ti(OiPr)4. In the mixture products, the Z-isomer predominates. 相似文献
96.
Chen Y Su W Bai M Jiang J Li X Liu Y Wang L Wang S 《Journal of the American Chemical Society》2005,127(45):15700-15701
LB films of three amphiphilic tris(phthalocyaninato) rare earth triple-decker complexes with crown-ethers as hydrophilic heads and long alkyl chains as hydrophobic tails have been prepared and found to display very well ordered layer structures, as proved by pi-A isotherms, UV-vis and polarized absorption spectra, X-ray diffraction experiments, and microscopic morphology characterization. These LB films have been fabricated into field-effect transistor (FET) devices, which show carrier mobilities as high as 0.24-0.60 cm2 V-1 s-1, among the highest mobilities achieved thus far for all LB film-based OFETs. 相似文献
97.
Weidong Li Yuan Liu Boyang Wang Haoqiang Song Zhongyi Liu Siyu Lu Bai Yang 《中国化学快报》1990,30(12):2323-2327
A facile, low-cost, green, kilogram-scale synthesis of high quality CQDs were synthesized. The throughput of CQDs is 1.4975 kg in one pot and the as-prepared CQDs have a highly crystalline hexagonal structure with remarkable solubility, stability, and biocompatibility. It showed outstanding electrocatalytic activity, Fe3+ sensitivity and good biocompatibility. 相似文献
98.
稀土—4—(2—吡啶偶氮)间苯二酚螯合物的高效液相色谱分离和测定 总被引:3,自引:0,他引:3
本文讨论了反相离子对液相色谱法分离和检测稀土-4-(2-吡啶偶氮)间苯二酚螯合物的各种条件,在12 min内完成了9种稀土螫合物的分离,校正曲线的线性范围是(ppm):La(0.01~3.20),Ce(0.03~2.8),Pr(0.06~3.5),Nd(0.05~3.8),Sm(0.01~3.0),Eu(0.05~3.4),Tb(0.02~3.0),Ho(0.01~3.4),Er(0.06~4.0).变异系数小于1.2%. 相似文献
99.
4,6-二氯-2-嘧啶基苯硫甲基磺酰脲与甲醇钠反应,合成了15个 见文献报道的标题化合物。它们的结构经IR,^1HNMR,MS,元素分析证实。其中一类化合物具有较强除草活性。 相似文献
100.
A novel concocting method to convert Triptolide (T) into Tripchlorolide (T(4)) in the traditional Chinese herb Tripterygium wilfordii Hook F. and a micellar electrokinetic capillary chromatographic (MEKC) approach by which the conversion of Triptolide (T) and Tripchlorolide (T(4)) was identified and determined had been established. Investigations of the influence of different pH values of boric acid and borax buffer and of sodium dodecyl sulfate (SDS) and organic additive concentrations had been carried out, and the optimum separation for T and T(4) was achieved using boric acid and borax of pH 7.0 with 30 mM SDS and 20% (volume ratio) methanol as the running buffer. It was found that MEKC exhibited good accuracy, precision and repeatability and the content of T(4) was greatly increased in the herb that was treated by the new concocting method. 相似文献