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191.
制备了以分散橙25为客体的掺杂型有机聚合物PMMA薄膜样品,对之进行了全光极化研究,极化使薄膜产生诱导二阶非线性光学效应,种子光的强度越大,其二阶非线性极化率达到的饱和值越大;种子光的位相差、相对强度比、光场强度等因素影响薄膜的二阶非线性的优劣. 相似文献
192.
J. -I. Toei 《Chromatographia》1987,23(5):355-360
Summary A liquid chromatographic procedure for separating nickel and zinc has been developed. Xylenol orange, which is one of the
sensitive and commercially available color-forming agents, was used as a component of the mobile phase. The two ions could
be separated on weak anion-exchange gels within 10 min. The procedure was suitable for the determination of nickel and zinc
in relatively pure solutions with fairly high sensitivity. The described liquid chromatographic analysis would be also potentially
applicable for any aqueous sample containing trace levels of metal cations at 1–10 ppm. 相似文献
193.
Hongli Wang Zhen Li Zuoquan Jiang Yanke Liang Hui Wang Jingui Qin Gui Yu Yunqi Liu 《Journal of polymer science. Part A, Polymer chemistry》2005,43(3):493-504
Two new orange red light‐emitting hyperbranched and linear polymers, poly(pyridine phenylene)s P1 and P2, were prepared by the Heck coupling reaction. In particular, an A2 + B3 approach was developed to synthesize conjugated hyperbranched polymer P2 via one‐pot polycondensation. The polymers were characterized by NMR, Fourier transform infrared, ultraviolet–visible, and elemental analysis. They showed excellent solubility in common solvents such as tetrahydrofuran, CH2Cl2, CHCl3, and N,N‐dimethylformamide and had high molecular weights (up to 6.1 × 105 and 5.8 × 105). Cyclic voltammetry studies revealed that P2 had a low‐lying lowest unoccupied molecular orbital energy level of ?3.22 eV and a highest occupied molecular orbital energy level of ?5.43 eV. The thin film of P2 emitted strong orange‐red photoluminescence at 595 nm. A double‐layer light‐emitting diode fabricated with the configuration of indium tin oxide/P2/tris(8‐hydroxy‐quinoline)aluminum/Al emitted orange‐red light at 599 nm, with a brightness of 662 cd/m2 at 7 V and a turn‐on voltage of 4.0 V; its external quantum efficiency was calculated to be 0.19% at 130.61 mA/cm2. This indicated that this new electroluminescent polymer (P2) based on 3,5‐dicyano‐2,4,6‐tristyrylpyridine could possibly be used as an orange‐red emitter in polymer light‐emitting displays. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 493–504, 2005 相似文献
194.
A thermometric titrimetry study of the interaction in aqueous solution of A13+, Co2+, Ni2+ and Zr4+ with xylenol orange has revealed in each case a linear reaction heat/[Mn+] relationship at a specified pH, thereby suggesting the potential of metallochromic indicators for the analytical determination of these metals in water. The effect of pH on the reaction heat is investigated and is interpreted in terms of the ability of these metal cations to complex with the known xylenol orange species existing at the various pH studied. An interference study, involving transition and non-transition metal ions, is also reported and the interference effect, as measured by the deviation ofQ/Q from unity (Q andQ are the relevant reaction heats in the presence and absence of interfering ion), is partially explained in terms of the coordination numbers, relative sizes and crystal field stabilization energies of the cations studied and the known behaviour of xylenol orange in aqueous solution. 相似文献
195.
By coupling flow-injection with laser-induced fluorescence detection, a setup was developed and a novel method combining fluorescence resonance energy transfer (FRET) and flow-injection analysis (FIA) was proposed for the determination of vitamin B12 (VB12) based on its fluorescence quenching on the system of acridine orange (AO)/rhodamine 6G (R6G). The effective energy transfer could occur between AO and R6G in the dodecyl benzene sodium sulfonate (DBS) while 454 nm argon laser was used as the excitation source, and as a result, the fluorescence emission of R6G has been increased significantly. It was found that the fluorescence of the above system could be sharply diminished by VB12. By using the mixed solution AO-R6G-DBS and the same solution containing VB12 as the carrier and sample, respectively, a series of negative peaks which could be applied for the quantification of VB12 were obtained. The detection limit for VB12 was 1.65 × 10−6 mol/L. The linear range for determining VB12 was 4 × 10−4 to 2 × 10−6 mol/L (correlation coefficient, r = 0.9923). The method was applied to measure VB12 injections with satisfactory results. 相似文献
196.
197.
以月桂酸为阴离子表面活性剂,3-胺丙基三乙氧基硅烷(APTES)为共结构导向剂,合成了高含量氨基功能化介孔氧化硅材料(AFMS)。以AFMS为吸附剂对溶液中酸性橙7(AO7)进行吸附,对影响AO7吸附效率的相关因素进行了详细研究,结果表明,溶液p H值及温度影响较大。吸附动力学表明,本研究中合成的AFMS对AO7的吸附速率极快。Sips吸附模型对吸附等温线模拟效果最好,从中可知AO7在样品D(由3.0 m L正硅酸乙酯及1.4 m L APTES合成)上的最大吸附量为1.26 mmol·g-1,远远高于相关文献报道的值。此外,通过吸-脱附循环实验证明,样品D具有良好的稳定性。 相似文献
198.
以葡萄糖溶液为原料,通过水热法制备了分散性良好的碳微球;以碳微球为模板,应用化学沉淀法和热处理技术除去碳核获得空心铬锌铁氧体;用钛酸四丁酯作为钛源,在空心铁氧体表面包覆二氧化钛制备了锌铬铁氧体/二氧化钛二元复合物.采用现代分析技术表征了制备样品的微观结构、形貌和电磁性能,并对其吸附和降解染料废水的性能进行了研究.结果表明,Zn Cr_(0.25)Fe_(1.75)O_4对染料废水具有较好的去污效果,对甲基橙和罗丹明B的去污效率分别为87%和83%;TiO_2对铁氧体的包覆能提高复合物对染料废水的光催化降解性能,其中m_(T/ZCF)=0.3的ZnCr_(0.25)Fe_(1.75)O_4/TiO_2复合物的去污效果最佳,几乎与纯二氧化钛相仿. 相似文献
199.
Chengyan Zhang Dan Ma Xiaobo Zhang Juanjuan Ma Lin Liu Xingyou Xu 《Journal of Coordination Chemistry》2016,69(6):985-995
Three 3-D metal-organic frameworks (MOFs), [Cd(NDC)(biim-4)]·0.5H2O (1), [Cd2(TDC)2(biim-4)2(H2O)2] (2) and [Zn2(biim-4)2(TDC)2]·2.5H2O (3) (biim-4 = 1,4-bis(1-imidazolyl) butyric alkyl; H2NDC = 1,4-naphthalene dicarboxylic acid; H2TDC = thiophene-2,5-dicarboxylic acid), have been synthesized under hydrothermal conditions and structurally characterized by single X-ray diffraction. The three MOFs have high photocatalytic degradation effects on methyl orange under UV irradiation. Through electronic structure analysis combined with time-dependent density functional theory calculations, catalytic performances of these materials are correlated with the molecular composition and the optoelectronic properties of the samples. 相似文献
200.
Liege A. Pascoalino Filipa S. Reis Miguel A. Prieto Joo C. M. Barreira Isabel C. F. R. Ferreira Lillian Barros 《Molecules (Basel, Switzerland)》2021,26(9)
Food processing generates a large amount of bio-residues, which have become the focus of different studies aimed at valorizing this low-cost source of bioactive compounds. High fruit consumption is associated with beneficial health effects and, therefore, bio-waste and its constituents arouse therapeutic interest. The present work focuses on the main Portuguese fruit crops and revises (i) the chemical constituents of apple, orange, and pear pomace as potential sources of functional/bioactive compounds; (ii) the bioactive evidence and potential therapeutic use of bio-waste generated in the processing of the main Portuguese fruit crops; and (iii) potential applications in the food, nutraceutical, pharmaceutical, and cosmetics industries. The current evidence of the effect of these bio-residues as antioxidant, anti-inflammatory, and antimicrobial agents is also summarized. Conclusions of the revised data are that these bio-wastes hold great potential to be employed in specific nutritional and pharmaceutical applications. 相似文献