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Abstract  

SCI has been popular all over the world since it was published by Garfield in 1963. Researches on evaluating a researcher’s output with SCI have always been continuous. In recent years, a great breakthrough has been made since the h-index was put forward in 2005. In this paper, we also advance a new method — Paper Quality Index (PQI) to evaluate the output of a researcher. The main purpose of our method is to solve two problems that consist in the method of h-index: one is that the h-index can’t compare the outputs of researchers in different fields; the other is that it is unsuitable for evaluating the outputs of young researchers. A simple mathematical expression is constructed to eliminate the difference of citation among different fields and makes the evaluation of short-term outputs of researchers possible.

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Abstract  

Sodium montmorillonite has been modified via cation exchange reaction using gemini surfactants. Montmorillonite modified by cetyltrimethyl ammonium bromide (CTAB) is used for comparation. Basal spacings and thermal stability of these organo-montmorillonite clays have been characterized using X-ray diffraction analysis and thermogravimetric analysis. The d(001) spacings of montmorillonite-Gemini14, montmorillonite-Gemini16, montmorillonite-Gemini18 can reach above 35 Å compared with the 23.66 Å of the montmorillonite-CTAB at 2.2CEC. The thermogravimetric analysis show four-step degradation which corresponds to residual water desorption, dehydration, followed by decomposition of the organic modifier and the dehydroxylation of the organo-montmorillonite. In addition, DTG enables two different structural arrangements of gemini surfactant molecules intercalating the montmorillonite to be proposed that is different from montmorillonite-CTAB.

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Abstract

TiO2–SiO2 catalysts for glycerol acetalization with acetone are synthesized by the sol–gel method and characterized by N2 adsorption–desorption, X-ray diffraction, NH3-temperature programmed desorption, Fourier transform infrared spectroscopy and ultraviolet–visible diffuse reflectance spectroscopy techniques in the present work. The effects of catalyst preparation and acetalization parameters such as reaction time, acetone/glycerol ratio, catalyst amount and reaction temperature on acetalization are investigated simultaneously. Pyridine adsorption results indicate that Ti–Si mixed oxides naturally only consist of Lewis acidic sites. The results of catalyst preparation and characterization show that Br⊘nsted acidic sites can be produced after Ti–Si mixed oxides adsorb water molecules, and TiO2–SiO2 (Si/Ti = 1) calcined at 550 °C exhibits the most total acidic density leading to the highest catalytic property in glycerol acetalization. The glycerol catalytic acetalization mainly occurs on the Br⊘nsted acidic sites. The effects of acetalization parameters indicate that the formation of the main product 5-membered ring ketal 2,2-dimethyl-1,3-dioxolane-4-yl methanol (about 90 %) is governed by kinetics. About 95 % glycerol conversion in acetalization is obtained under the optimum conditions.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: Yanjiang Han, Duanzhi Yin, Mingqiang Zheng, Wei Zhou, ZhenHong Lee, Lan Zhan, Yufei Ma, Mingxing Wu, Lingli Shi, Ni Wang, Jianbo Lee, Cheng Wang, Zheng Lee, and Yongxian Wang

Abstract  

The aim of this study was to develop a radiopharmaceutical for the imaging of CXCR4-expressing tumors in vivo. For 125I-labeling, 125I-SIB was synthesized and conjugated with the ε-NH2 group of Ac-TZ14011, a specific CXCR4 antagonist. The specific radioactivity of the product was 5 GBq/μmol and the radiochemical purity (RCP) was 96% (n = 3). After 6 h, the RCP of the product in PBS was 93%. The MCF-7 cell uptake of Ac-TZ14011 was rapid and high. Primary biodistribution studies indicated that 125I-IB-Ac-TZ14011 was mainly excreted via the kidney, and further evaluation in mice with induced tumors was necessary.

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