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EFFECT OF ORTHO-METHOXYCINNAMIC ACID ON THE SOL-GEL TRANSITION OF METHYLCELLULOSE SOLUTIONS IN THE PRESENCE OF cetyltrimethylammonium bromide

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Chinese Journal of Polymer Science 2013年第2期31卷 263-274页

作者： Jun Tao 杨海洋 Xiang Hao Yong-jun Xie Hua-yu Li School of Chemistry and Materials Science University of Science and Technology of China

The sol-gel transition of methylcellulose （MC） solutions in the presence of ortho-methoxycinnamic acid （OMCA） or cetyltrimethylammonium bromide （CTAB） and in the coexistence of OMCA and CTAB was determined by the rheological measurement. It has been found that the sol-gel transition temperature of MC solutions increases linearly with the concentration of either OMCA or CTAB in solution, respectively. However, in the coexistence of OMCA and CTAB, the sol-gel transition temperature of MC solutions remains invariable, independent of the concentration of CTAB in solution. The experimental results show that OMCA has priority to adsorb on the methyl group of MC chains to form polymer-bound aggregates. In particular, these aggregates inhibit the hydrophobic interaction between CTAB and the methyl group of MC chains completely. Taking into account the fact that OMCA is almost insoluble in MC-free solutions but dissolves very well in aqueous MC solutions, we propose the formation of the core-shell architecture prompted by OMCA and the methyl group of MC chains, with the methyl group of MC chains serving as the core and the self-assembly of OMCA molecules serving as the shell. Obviously, the formation of the core-shell structure increases the solubility of OMCA, improves the stability of methyl groups of MC chains at high temperatures and inhibits the hydrophobic interaction between CTAB and the methyl group of MC chains in solution. The abnormal behavior relating to the sol-gel transition of MC solutions in the presence of OMCA or in the coexistence of OMCA and CTAB is therefore explained. Upon UV irradiation, the sol-gel transition temperature of MC solutions in the presence of OMCA, or in the coexistence of OMCA and CTAB, decreases notably. However, the dependence of the sol-gel transition temperature of MC solutions as a function of OMCA concentration, or CTAB concentration in the presence of OMCA, does not change after UV irradiation.

关键词： Methylcellulose Ortho-methoxycinnamic acid cetyltrimethylammonium bromide Sol-gel transition Hydrophobic interaction.

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Influence of Low cetyltrimethylammonium bromide Concentration on the Interactions and Properties of Hemoglobin with Acyclovir

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Chinese Journal of Chemistry 2006年第5期24卷 620-626页

作者：刘天睛郭荣 School of Chemistry and Chemical Engineering Nanjing University Jiangsu 210093 China School of Chemistry and Chemical Engineering Yangzhou University Yangzhou Jiangsu 250002 China

The effects of cetyltrimethylammonium bromide （CTAB） on the properties of hemoglobin （Hb） at low CTAB concentration were studied in Hb/acyclovir/CTAB system by the methods of UV-Vis spectrum, fluorescence, zeta potential, conductivity and negative-staining transmission electron microscope （TEM）. With the increase of CTAB concentration, the UV peak intensity at 276 nm, the intrinsic fluorescence, the zeta potential of Hb and the system conductivity were all enhanced. Hb was easily oxidized to oxyHb and hemichrome. In Hb/acyclovir/CTAB system, CTAB made the UV-Vis spectrum, fluorescence, conductivity and conformation of Hb tend to be returned to those of the original Hb but the zeta potential not to do so. The UV absorption peak of Hb-acyclovir complex disappeared and the tight structure of Hb aroused by acyclovir was refolded. When CTAB concentration was higher than 5 × 10 ^5 mol/L, the two absorption peaks at 536 and 576 nm appeared again, and the Hb structure became looser again.

关键词： hemoglobin cetyltrimethylammonium bromide acyclovir property interaction

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Novel Approach to Characterization of Rare Earth Complexation with 1, 5-Bis(2-Hydroxy-5-Chlorphenyl)-3-Cyanoformazan in Presence of cetyltrimethylammonium bromide

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Journal of Rare Earths 2002年第5期20卷 525-532页

作者：郑立新胡张军郜洪文 Anhui Univ Sch Chem & Chem Engn Hefei 230039 Peoples R China

The ternary interaction of 1, 5 bis(2 hydroxy 5 chlorphenyl) 3 cyanoformazan (HCPCF) with cetyltrimethylammonium bromide (CTAB) and rare earths (RE: Yb, Dy, Er and Eu) was investigated at pH 9.84 by the microsurface adsorption spectral correction technique (MSASC). The aggregation of HCPCF on CTAB obeys the Langmuir isothermal adsorption and the interaction of RE with the HCPCF CTAB aggregate was first found to accord with the monolayer binding. The effects of temperature and ionic strength of solution on the aggregations were made. The binary aggregate and the ternary complex were characterized.

关键词： rare earths microsurface adsorption spectral correction technique langmuir aggregation cetyltrimethylammonium bromide 1,5 bis(2 hydroxy 5 chlorphenyl) 3 cyanoformazan ternary complex

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Effects of cationic cetyltrimethylammonium bromide on aggregation behaviors of sodium lignosulfonate in concentrated solutions

Effects of cationic cetyltrimethylammonium bromide on aggreg...

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河南省化学会2016年学术年会

作者： Qianqian Tang College of Chemistry and Chemical Engineering and Henan Key Laboratory of Function-Oriented Porous Materials Luoyang Normal University

Effects of cationic cetyltrimethylammonium bromide(CTAB) on aggregation behaviors of sodium lignosulfonate(Na LS) in concentrated solutions were investigated by rheology, conductivity, zeta potential and surface tension measurements. Results showed the presence of CTAB led to increased aggregate effects and enhanced association networks due to intermolecular bridging caused by the formation of mixed aggregates containing Na LS hydrophobes and CTAB molecules at CTAB/Na LS mixing ratios(w/w) below 1:7. However, further additions of CTAB resulted in the progressive disruption of network structures due to electrostatic repulsion between aggregates. The above results also revealed stoichiometric mass ratio(SMR) of Na LS/CTAB system, where the hydrophobicity was strongest and to prepare colloidal spheres was feasible.

关键词： sodium lignosulfonate concentrated solutions cetyltrimethylammonium bromide aggregation rheology

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Preparation of Mesoporous Nano-Hydroxyapatite Using a Surfactant Template Method for Protein Delivery

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Journal of Bionic Engineering 2012年第2期9卷 224-233页

作者： Xiaodong Wu Xiaofeng Song Dongsong Li Jianguo Liu Peibiao Zhang Xuesi Chen Department of Bone and Joint Surgery First Hospital of Jilin UniversityChangchun 130021P R.China Key Laboratory of Polymer Ecobiomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangehun 130022P.R.China

Mesoporous nano-hydroxyapatite （n-HA） has gained more and more attention as drug storage and release hosts. The aim of this study is to observe the effect of the ratio of surfactant to the theoretical yield of HA on the mesoporous n-HA, then to reveal the effect of the mesoporous nanostructure on protein delivery. The mesoporous n-HA was synthesized using the wet precipitation in the presence of cetyltrimethylammonium bromide （CTAB） at ambient temperature and normal atmospheric pressure. The morphology, size, crystalline phase, chemical composition and textural characteristics of the product were well characterized by X-ray Powder Diffraction （XRD）, Fourier Transform Infrared Spectroscopy （FTIR）, Scanning Electron Microscopy （SEM）, Transmission Electron Microscopy （TEM）, Dynamic Light Scattering （DLS） and N2 adsorption/desorption, respectively. The protein adsorption/release studies were also carried out by using Bovine Serum Albumin （BSA） as a model protein. The results reveal that the mesoporous n-HA synthesized with CTAB exhibits high pure phase, low crystallinity and the typical characteristics of the mesostructure. The BSA loading increases with the specific surface area and the pore volume of n-HA, and the release rates of BSA are different due to their different pore sizes and pore structures, n-HA synthesized with 0.5% CTAB has the highest BSA loading and the slowest release rate because of its highest surface area and smaller pore size. These mesoporous n-HA materials demonstrate a potential application in the field of protein delivery due to their bioactive, biocompatible and mesoporous properties.

关键词： hydroxyapatite nanoparticles mesostructure cetyltrimethylammonium bromide drug delivery

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Preparation and Properties of the Heteropolyoxometalates of Large Organic Cation with Molybdotungstosilicic Acids

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Journal of Wuhan University of Technology(Materials Science) 2008年第2期23卷 198-203页

作者： WANG Dunjia FANG Zhengdong WEI Xianhong Hubei Key Laboratory of Bioanalytical Technique Department of Chemistry and Environmental Engineering Hubei Normal University Huangshi 435002 China

Some new heteropolyoxometalates of large organic cations with molybdotungstosilicic acids （general formula：（CTMA）4SiMoxW12-xO40·mH2O·nDMF, x=0,2,4,6,8,10,12） were prepared by the reaction of cetyltrimethylammonium bromide （CTMAB,C16H33N（CH3）3Br） with H4SiMoxW12-xO40（x=0,2,4,6,8,10,12） in aqueous solution and recrystallization in DMF, and characterized by elemental analysis, IR spectra,TG- DTA and XRD techniques. The IR spectrum confirms the presence of Keggin structure and organic cations in these compounds, and it is indicated that the stretching vibration of the M-Od, M-Ob-M and Si-Oa becomes more red-shifted when molybdenum is gradually substituted for the tungsten atom. In particular, the thermal decomposition of the heteropolyoxometalates was studied in nitrogen atmosphere. The TG-DTA curves show that their thermal behaviors not only contain the release of water molecule, DMF molecule, CTMA and its fragments but also contains simultaneous collapse of Keggin anion. Their end products of the thermal decomposition are the mixture of WO3, MoO3 and SiO2. And from the final decomposition temperature of view, it is found that the thermal stability of these compounds gradually is decreased when the number of molybdenum atoms is increased.

关键词： heteropolyoxometalates molybdotungstosilicic acid cetyltrimethylammonium bromide IR spectral and thermal study

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A conductive anionic Co-MOF cage with zeolite framework for supercapacitors

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中国化学快报：英文版 2020年第9期31卷 2309-2313页

作者： Wei Du Yue-Ling Bai Zhen Yang Runlong Li Dan Zhang Zhiheng Ma Anbao Yuan Jiaqiang Xu College of Science Shanghai UniversityShanghai 200444China

Conductive MOFs could exhibit full potential as integrated electrode materials for supercapacitors without interference from additional conductive *** we report an anionic Co-MOF cage with zeolite framework,which was balanced by the redox-active guest [Co(H2O)6]2+ and protonated[(CH3)2NH2]2+ *** from the unique ion skeleton structure,Co-MOF exhibits a conductivity higher than most of reported MOFs with the value of 1.42 × 10^-3 S/cm,which can be directly fabricated as electrode for supercapacitors.A maximum specific capacitance of 236.2 F/g can be achieved at a current density of 1 A/g of ***,the electric performance and morphology of this Co-MOF can be modified by cetyltrimethylammonium bromide(CTAB) and the maximum specific capacitance could increase up to 334 F/g at 1 A/g when the ratio of ligand and CTAB is 1:6(Co-MOF-6).Furthermore,the specific capacitance can retain at 64.04% and 77.92% of the initial value after 3000 cycles of Co-MOF and Co-CTAB-6,***,the addition of CTAB further improves both capacitance and cycle stability.

关键词： Metal organic frameworks Supercapacitors cetyltrimethylammonium bromide In-situ growth Redox-active guest

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Removal of Pollutants of Landfill Leachate by Recirculation

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Journal of Wuhan University of Technology(Materials Science) 2008年第2期23卷 281-284页

作者： LI Ye WANG Lina ZHENG Shizhong School of Resources and Environmental Engineering Wuhan University of Technology Wuhan 430070 China The Landfill of Hongmiaoling in Fuzhou City

SAfter leached from municipal solid waste landfill was treated by recirculation, the concentration of pollutants decreases greatly, and the moisture content of the solid waste in landfill site was increased and waste stabilization rate was accelerated. Compared with traditional treatment methods, this method offers more important practical values, including short investment, enhanced treatment efficiency and facilitated operation and management. The experimental results indicated that a 99.9% removal of ammonia nitrogen and an 80.5% removal of COD were obtained, when hydraulic power surface load is 15.92 L/m^2·d, and organic surface load is 25.54 g/m^2·d.

关键词： heteropolyoxometalates molybdotungstosilicic acid cetyltrimethylammonium bromide IR spectral and thermal study

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Influence of Mixed Micelle on the Sensitized Coordination Compound of Gallium (Ⅲ) with o-Chlorophenylfluo-rone and Its Analytical Application

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工程科学学报 1991年第4期 385-392页

作者：陈华序邵光玓夏心龙北京科技大学化学系

After comparing the sensitizing effect of various mixed surfactants on the chromophoric reaction of gallium (Ⅱ) with orthochlorophenylf luorone, it has been found that the mixed micelle of cetyltrimethylammonium bromide and Tween-80 is most suitable. In the presence of this mixed micelle, not only both the sensitivity and stability improve markedly, but also a wider pH range is tolerable for the colour-development. From the study on the optimum conditions for the formation of the coloured coordination compoundin the system of 《Ga (Ⅱ)--o-Chlorophenyl fluorone-catyltrimethylammo-nium bromide--Tween-80》 and its main characters, a spectrophotometricmethod, by which sensitivity and reproducibility are higher than those of ternary systems of gallium(Ⅱ) has been developed. When it is combined with the dual-wavelength method, the molar absorptivity can be improved to 2.33×105 l·mol-1·cm-1,which is higher than that of most of other systems ever shown in the literatures; moreover the linear range is exten

关键词： gallium orthochlorophenylfluorone cetyltrimethylammonium bromide mixed micelle sensitization

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