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101.
A titrimetric and spectrophotometric methods for cerium(IV) determination have worked out. The first method relies upon the treatment of cerium(IV) solution with an excessive amount of iodide; the liberated iodine is extracted into chloroform, then reduced to iodide. The latter is iodometrically determined after 6- or 36-fold amplification. The spectropho-tometric finish is based upon the reaction of the titled ion with iron(II), in the presence of hexacyanoferrate(II), to form an intense prussian blue color suitable for the trace determination of cerium(IV) ion. 相似文献
102.
The possible lattice formation of grains of chosen material in a magnetized current carrying n-type piezoelectric semiconductor plasma has been examined. In addition to the repulsive Coulomb potential, there appears
a non-Coulombic oscillatory potential among the highly charged grains due to the strong resonant collective interaction of
the grains and the electron-acoustic mode of the host semiconductor giving rise to the possibility of the lattice formation
of grains of new materials. 相似文献
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105.
Xiaodong Hou Qiaobo Li Yong He Lin Jia Yang Li Yingdan Zhu Amin Cao 《Journal of Polymer Science.Polymer Physics》2009,47(14):1393-1405
Spontaneous stereocomplex aggregation of diblock poly(styrene)‐b‐poly(L ‐lactide) PS‐b‐PLLA/poly(D ‐lactide) PDLA pairs has been investigated under ambient temperature in tetrahydrofuran solution. First, diblock PS260‐b‐PLLA165 and PS260‐b‐PDLA162 bearing similar lengths of respective PLLA and PDLA blocks were synthesized through controlled atom‐transfer radical polymerization of styrene, and a subsequent living ring‐opening polymerization of optically pure lactides, and their structures were further characterized by nuclear magnetic resonance spectroscopy (NMR) and gel‐permeation chromatography (GPC). Subsequently, new enantiomeric poly(D ‐lactide) stabilized core‐shell fluorescent CdSe quantum dots (CdSe/PDLA QD) were designed and prepared as sensitive fluorescence labels to shed new lights on the spontaneous stereocomplex aggregation in THF, which was mediated by stereocomplexation of the PLLA and PDLA chains. Upon simply mixing two individual THF solution of diblock PS260‐b‐PLLA165 and HO‐PDLA30‐SH, spontaneous stereocomplex aggregation was studied, and the aggregated uniform spherical particles were observed by scanning electronic microscopy (SEM) to exhibit average particle diameters of 2.0 μm. Finally, utilizing the prepared CdSe/PDLA QDs as new fluorescent labels, morphologies of the spontaneous aggregates by new diblock PS260‐b‐PLLA165/HO‐PDLA30‐SH pair were for the first time directly visualized by a confocal laser scanning fluorescence microscopy (CLSFM). These results might suggest alternative ways to simply prepare functional fluorescent particles with tunable diameter sizes and would be helpful to understand the mechanism of stereocomplex particle aggregation. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 1393–1405, 2009 相似文献
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107.
Jahangeer Patujo Amin Badshah Raja Azadar Hussain Muhammad Nawaz Tahir Shaista Tahir Muhammad Khawar Rauf 《中国化学会会志》2015,62(11):1020-1027
In the present work new nitro substituted thioureas, and their copper complexes have been synthesized and characterized by FTIR and multinuclear NMR techniques. Some of the compounds namely 1‐benzoyl‐3‐(4‐chloro‐3‐nitrophenyl) thiourea (A‐1), 1‐benzoyl‐3‐(4‐chloro‐3‐nitrophenyl) thiourea (A‐2) and 1‐benzoyl‐3‐(2‐methoxy‐4‐nitrophenyl) thiourea (A‐2) have also been characterized by single crystal XRD. All the synthesized compounds have been screened for DNA binding potencies (using cyclic voltametry, UV‐vis spectroscopy) and free radical scavanging activities. 相似文献
108.
Ali Heba Ismail N. Amin M. S. Mekewi Mohamed 《Journal of Solid State Electrochemistry》2017,21(6):1605-1613
Journal of Solid State Electrochemistry - Efficient photoanodes are designed of vertically aligned anatase TiO2 nanotube arrays (anatase TNTAs) decorated with different shaped rutile TiO2... 相似文献
109.
H.?HussienEmail author A.?A.?Goud A.?M.?Amin R.?EL-Sheikh U.?Seddik 《Journal of Radioanalytical and Nuclear Chemistry》2011,288(1):9-15
This study describes a fast and efficient method for radiolabeling of etodolac with iodine-125 [125I], where both chloramine-T and iodogen were used as oxidizing agents. The labeling reaction was carried out via electrophilic
substitution of hydrogen atom with the iodonium cation I+. The labeling yield was found to be influenced by different factors such as drug concentration, pH of the reaction mixtures,
different oxidizing agents, reaction time, temperature and different organic media. The radiochemical yield (RCY) was determined
by TLC system using methylene chloride:ethyl acetate (3:7 v/v) as a developing solvent and by electrophoresis using cellulose
acetate moistened with 0.02 M phosphate buffer pH 7. The maximum radiochemical yield of [125I]Etodolac (87.7%) was obtained. Labeled etodolac shows a good localization in inflamed muscle. It excretes mainly via kidney
and to some via liver. 相似文献
110.
Tracer particle microrheology using diffusing wave spectroscopy-based microrheology is demonstrated to be a useful method to study the dynamics of aqueous Pluronic? F108 solutions, which are viewed as solutions of repulsive soft spheres. The measured zero-shear microviscosity of noncrystallizing micellar dispersions indicates micelle corona dehydration upon increasing temperature. Colloidal sphere thermal motion is shown to be exquisitely sensitive to the onset of crystallization in these micellar dispersions. High temperature dynamics are dominated by an apparent soft repulsive micelle-micelle interaction potential indicating the important role played by lubrication forces and ultimately micelle corona interpenetration and compression at sufficiently high concentrations. The measured microscopic viscoelastic storage and loss moduli are qualitatively similar to those experimentally observed in mechanical measurements on colloidal dispersions and crystals, and calculated from mode coupling theory of colloidal suspensions. The observation of subdiffusive colloidal sphere thermal motion at short time-scales is strong evidence that the observed microscopic viscoelastic properties reflect the dynamics of individual micelles rather than a dispersion of micellar crystallites. 相似文献