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91.
《Analytical letters》2012,45(4):537-552
Abstract The formation and extraction of copper (II) in the form of benzyl bismuthiol and naphthyl bismuthiol chelates has been studied. The reagents' solvation in butanone is investigated and optimum conditions for extraction are established. Both chelates have been studied in solution and in solid form. After studying the influence of 14 possible interferences, an atomic absorption spectrometric determination of copper using both reagents was carried out in tap water samples. 相似文献
92.
甲基丙烯酸三丁基锡酯与甲基丙烯酸甲酯共聚物的分子量测定和K、α值的订定 相似文献
94.
95.
硒(Ⅳ)-硫氰酸钾-甲基紫萃取光度法测定痕量硒 总被引:6,自引:0,他引:6
研究了硒(Ⅳ)与硫氰酸钾和甲基紫(MV)的显色反应,发现在pH=1.85的HCl介质中,[Se(SCN)_6)~(2-)与MV形成不溶解于水的三元离子缔合物,该缔合物可溶解于苯等有机溶剂,在苯溶液中,该缔合物的最大吸收峰位于600nm处,其摩尔吸光系数为1.18×10~5L/(mol·cm),硒(Ⅳ)浓度在0.0~6.0μg/25mL范围内符合比耳定律。该方法应用于合成水样和环境水样中硒的测定,结果准确、可靠。 相似文献
96.
PHOTOCHROMISM AND LUMINESCENCE OF DOPANT CHROMOPHORES THROUGH TWO-PHOTON IONIZATION IN POLYMER FILMS
Two-photon ionization and recombination processes of an aromatic chromophore doped in polymer films werestudied and the features of these processes were discussed in relation to photofunctional polymers, An aromatic moleculehaving low ionization potential, e.g., N,N,N',N'-tetramethyl-p-phenylene diamine doped in poly(methyl methacrylate)(PMMA) film was easily photoionized by intense laser ligh excitation, giving a colored radical cation (photochromism) anda trapped electron in PMMA matrix. As a reversed process, the radical cation recombined with the trapped electron, showingdiscoloration and emitting luminescence, either isothermal luminescence (ITL), or thermoluminescence (TL). In this report,ITL and TL through the charge recombination process were studied and the luminescence was suggested as a mean of the read-out of photorecording. 相似文献
97.
Chizhov D. L. Ratner V. G. Pashkevich K. I. Antipin M. Yu. Khrustalev V. N. 《Russian Chemical Bulletin》2001,50(1):101-103
Hexane-2,5-dione or 1,1,1,10,10,10-hexafluorodecane-2,4,7,9-tetrone react with methyl trifluoroacetate in the presence of LiH to give, upon treatment with diluted acid, 6-hydroxy-9-oxo-2,4,10-tris(trifluoromethyl)-3,11,12-trioxatetracyclo[5,2,1,02,6,04,10]dodecane. The structure of this compound was determined by X-ray diffraction study. 相似文献
98.
Song Gu Yang Gao Xiuyan Ren Jianhong Yu Lijie Duan Guanghui Gao 《Journal of polymer science. Part A, Polymer chemistry》2018,56(22):1505-1512
Hydrophobic association hydrogels were fabricated via micellar copolymerization of acrylamide and hydrophobic monomers lauryl (meth)acrylate (LA or LMA) in an aqueous solution of sodium dodecyl sulfate. The effect of methyl groups of hydrophobic monomers on the crosslinking network structure and mechanical behavior of the gels was investigated on the basis of rubber elastic theory. It was found that the LMA-gel exhibited higher effective crosslink density and elastic modulus. The methyl groups of hydrophobic monomers limited the flexibility of the methacrylate backbone in the association domain, which resulted in the increment of chains constraints. With the increase of stretch rate, the dissipated energy of LMA-gel increased more highly than that of LA-gel. In addition, the methyl group hindered the movement of polymer chains, leading to the lower recovery efficiency of dissipated energy for LMA-gel. In contract, the LA-gel exhibited a rapid response to external force, and possessed better elasticity and self-recovery property. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018 , 56, 1505–1512 相似文献
99.
A high‐activity AgBr/Ag3PO4 heterojunction photocatalyst was synthesized based on hexadecyltrimethylammonium bromide. Its microspheres were characterized using X‐ray diffractometry, transmission electron microscopy and ultraviolet–visible diffuse reflectance spectroscopy. The new photocatalyst with high photocatalytic activity exceptionally outperforms pure Ag3PO4 and AgBr in methyl orange degradation. The enhancement of photocatalytic activity is attributed to the efficient separation of electron–hole pairs. In this photocatalytic reaction, h+ and ?O2? are the main reactive species that induce visible‐light‐driven degradation. 相似文献
100.
《Journal of mass spectrometry : JMS》2018,53(5):379-384
Gas phase decompositions of protonated methyl benzoate and its conjugates have been studied by using electrospray ionization‐collision induced dissociation‐tandem mass spectrometry. Loss of CO2 molecule, thus transfer of methyl group, has been observed. In order to better understand this process, the theoretical calculations have been performed. For methyl benzoate conjugates, it has been found that position of substituent affects the loss of CO2 molecule, not the electron donor/withdrawing properties of the substituent. Therefore, electrospray ionization‐mass spectrometry in positive ion mode may be useful for differentiation of isomers of methyl benzoate conjugates. 相似文献