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Ternary Diffusion Coefficients of 1-Hexanol-Hexane-Toluene and 1-Propanol-Water-Ethylene Glycol by Taylor Dispersion Method

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Tsinghua Science and Technology 2005年第5期10卷 523-528页

作者：任钟旗费维扬 Hans-Joerg Bart State Key laboratory of solvent extraction Department of Chemical Engineering Tsinghua University Beijing 100084 China Institute of Chemical Engineering University of Kaiserslautern Kaiserslautern 67653 Germany

The Taylor dispersion method was used to measure diffusion coefficients of three-component liquid systems. An improved constrained nonlinear least-square method was used to evaluate the ternary diffusion coefficients directly by fitting the mathematical solutions of the dispersion equation to eluted solute peaks detected using a differential refractometer. Diffusion coefficients of the three-component system of acetone-benzene-CCl4, determined at 25℃, were used to test the procedure. The measured diffusion coefficients were compared with values obtained by optical interferometry and the diaphragm cell method. Ternary diffusion coefficients are also determinated for solutions of 1-hexanol-hexane-toluene and 1-propanol- water-ethylene glycol at 25℃, with an accuracy of approximately 0.05 m^2·s^- 1.

关键词： Taylor dispersion method ternary diffusion coefficient constrained nonlinear least-squared method Fick law

Synthesis of ordered mesoporous crystalline boron phosphate scaffold with double diamond surface structure

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Science China Chemistry 2025年第2期68卷 590-600页

作者： Chao Wang Wen-Duo Lu Jiao Wang Shunai Che An-Hui Lu Lu Han School of Chemical Science and Engineering Tongji UniversityShanghai 200092China State Key laboratory of Fine Chemicals Liaoning Key Laboratory for Catalytic Conversion of Carbon ResourcesSchool of Chemical EngineeringDalian University of TechnologyDalian 116024China School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative MoleculesState Key Laboratory of Metal Matrix CompositesShanghai Key Laboratory for Molecular Engineering of Chiral DrugsShanghai Jiao Tong UniversityShanghai 200240China

Ordered mesoporous materials have received great attention due to their well-defined pore structures and potential applications in catalysis,adsorption,separation,drug delivery,*** various compositions of mesoporous solids have been successfully prepared,the preparation of crystalline non-metallic oxyacid salts with ordered mesoporosity remains a major ***,we report the synthesis of a mesoporous solid acid crystalline boron phosphate(BPO_(4))catalyst with a bicontinuous shifted double diamond(SDD)hyperbolic surface *** BPO_(4) scaffold was obtained by synergistic selfassembly in a mixed solvent of water and tetrahydrofuran using the diblock copolymer poly(ethylene oxide)-block-polystyrene as template and phosphoric acid and orthoboric acid as inorganic *** structure consists of two sets of diamond networks adjacent to each other with a mesostructural scale tetragonal symmetry(space group I4_(1)/amd)with unit cell parameters of a=80 nm and c=113 nm,which affords the scaffold a specific surface area of 44 m^(2)/*** a solid acid catalytic material,the SDD BPO_(4) scaffold exhibited excellent catalytic activity at room temperature with a conversion of furfural to 2-(dimethoxymethyl)furan over 70%and can be reused after recovery without serious loss of *** the propane oxidative dehydrogenation reaction,SDD BPO_(4) demonstrated high olefin productivity and selectivity while maintaining high reaction *** study provides ideas for the preparation of ordered mesoporous crystalline catalytic materials and demonstrates their potential for practical applications.

关键词： boron phosphate mesoporous material self-assembly block copolymer catalyst

Biisoindolylidene solvatochromic fluorophores: Synthesis and photophysical properties

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Chinese Chemical Letters 2025年第2期36卷 394-399页

作者： Xiaoyu Chen Jiahao Hu Jingyi Lin Haiyang Huang Changqing Ye Hongli Bao College of Chemistry Fuzhou University State Key laboratory of Structural Chemistry Key Laboratory of Coal to Ethylene Glycol and Its Related TechnologyCenter for Excellence in Molecular SynthesisFujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fujian College University of Chinese Academy of SciencesFuzhou 350002China dUniversity of Chinese Academy of Sciences

Environment-sensitive fluorescent probes are commonly utilized in various fields, including fluorescence sensing and imaging. This paper describes the synthesis and photophysical properties of a novel class of solvatochromic fluorophores that incorporate biisoindolylidene as the core backbone. This study investigates the structure-property relationships of these newly developed fluorophores. The central biisoindolylidene acts as an efficient electron acceptor, and by modifying the aryl ring substituent at the 3,3 position, the photophysical properties of the fluorophores can be significantly enhanced, particularly in terms of photoluminescence quantum efficiency. Furthermore, when an electron-donor group replaces the aryl ring at the 3,3 position, intriguing solvatochromic behavior is observed. This leads to a red-shift in the maximum emission wavelength and an increase in the Stokes shift with increasing solvent polarity. In solvent dimethyl sulfoxide(DMSO), the maximum emission wavelength can reach up to 750 nm,with a Stokes shift of approximately 150 nm. Finally, the potential application of the fluorophore in the detection of volatile acids is explored in a preliminary manner.

关键词： Acid sensitive Biisoindolylidene Electron receptor New fluorophores Solvatochromic

Methyl Groups Pendant on Triphenylmethane Toward Modulating Thermal Stability and Dielectric Properties of the Crosslinkable Fluorinated Polyimide Films with High Transparency

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Chinese Journal of Polymer Science 2025年第2期43卷 316-327页

作者： Wen Yang Liang Yuan Kai Gong Ruo-Han Zhang Lan Lei Hui Li School of Chemistry and Chemical Engineering Shandong Key Laboratory of Fluorine Chemistry and Chemical Engineering MaterialsUniversity of JinanJinan250022China School of Materials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin UniversityTianjin300350China

It is urgent to develop high-performance polyimide(PI)films that simultaneously exhibit high transparency,exceptional thermal stability,mechanical robustness,and low dielectric to fulfil the requirements of flexible display ***,a series of fluorinated polyimide films(FPIs)were fabricated by the condensation of 5,5′-(perfluoropropane-2,2-diyl)bis(isobenzofuran-1,3-dione)(6FDA)and the fluorinated triphenylmethane diamine monomer(EDA,MEDA and DMEDA)with heat-crosslinkable tetrafluorostyrene side groups,which was incorporated by different numbers of methyl groups pendant in the ortho position of amino ***,the FPI films underwent heating to produce crosslinking FPIs(C-FPIs)through the self-crosslinking of double bonds in the *** transparency,solvent resistance,thermal stability,mechanical robustness and dielectric properties of FPI and C-FPI films can be tuned by the number of methyl groups and crosslinking,which were deeply investigated by virtue of molecular dynamics(MD)simulations and density functional theory(DFT).As a result,all the films exhibited exceptional optically colorless and transparent,with transmittance in the visible region of 450-700 nm exceeding 79.9%,and the cut-off wavelengths(λ_(off))were nearly 350 *** thermal decomposition temperatures at 5% weight loss(T_(d5%))for all samples exceeded 504℃.These films exhibited a wide range of tunable tensile strength(46.5-75.1 MPa).Significantly,they showed exceptional dielectric properties with the dielectric constant of 2.3-2.5 at full frequency(10^(7)-20 Hz).This study not only highlights the relationship between the polymer molecular structure and properties,but offer insights for balancing optical transparency,heat resistance and low dielectric constant in PI films.

关键词： Crosslinkable fluorinated polyimide Methyl group Triphenylmethane Transparency Thermal stability Low dielectric constant

A novel and visible ratiometric fluorescence determination of carbaryl based on red emissive carbon dots by a solvent-free method

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Chinese Chemical Letters 2025年第2期36卷 314-318页

作者： Meiling Xu Xinyang Li Pengyuan Liu Junjun Liu Xiao Han Guodong Chai Shuangling Zhong Bai Yang Liying Cui College of Resources and Environment Jilin Agricultural University State Key laboratory of Supramolecular Structure and Materials College of Chemistry Jilin University Key laboratory of Straw Biology and Utilization The Ministry of Education Jilin Agricultural University

In this study, a simple and effective ratiometric fluorescence method has been developed for carbaryl detection, utilizing red emissive carbon dots（R-CDs）. The underlying principle of this proposed strategy relies on the rapid hydrolysis of carbaryl under an alkaline condition and production of 1-naphthol with blue-emission at 462 nm. Furthermore, the as-synthesized R-CDs（Em. 677 nm）, serve as a reference, enhancing the visual tracking of carbaryl through the transformation of fluorescent color from red to *** concentration of carbaryl exhibits a commendable linear correlation with the ratio of fluorescence intensity, ranging from 0 to 20 μg/m L（R2= 0.9989） with a low detection limit of 0.52 ng/m L. Additionally, the described methodology can be used for the enzyme-free visual assay of carbaryl, even in the presence of other carbamate pesticides and metal ions, in tap water and lake water samples with excellent accuracy（spiked recoveries, 94%–106.1%）, high precision(relative standard deviation（RSD） ≤ 2.42),and remarkable selectivity. This fast and highly sensitive naked-eye ratiometric sensor holds immense promise for carbaryl detection in intricate environments and food safety fields.

关键词： Carbaryl detection Carbon dots Fluorescence sensor Quantum yield Visual detection

Separation of Organic Dyes from Water by Colloidal Gas Aphrons

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Tsinghua Science and Technology 2002年第1期7卷 46-51页

作者：黄颖怡王运东戴猷元 State Key laboratory of solvent extraction Department of Chemical Engineering Tsinghua University Beijing 100084 China

Colloidal gas aphrons (CGAs) are micron sized gas bubbles produced by stirring surfactant solutions at high speed. A single CGA dispersed in water is composed of a gaseous inner core, surrounded by a double water soapy layer. CGAs have large interfacial area per unit volume and exhibit relatively high stability. These characteristics make CGAs very suitable in flotation systems. This paper studied the flotation of organic dyes from water using CGAs. The experimental results show that the flotation process may follow four mechanisms, i.e., ion coupling of the oppositely charged species of the surfactant forming the CGA and the organic dye, reactions between CGA and the organic dye, ion dye complex adsorbed on the surface of CGAs, and hydrophilic or hydrophobic characteristics of the organic dyes. 

关键词： colloidal gas aphrons (CGAs) flotation organic dye surfactant

Deep eutectic solvents for separation and purification applications in critical metal metallurgy:Recent advances and perspectives

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 1-19页

作者： Shuo Chen Shengpeng Su Yanfang Huang Bingbing Liu Hu Sun Shuzhen Yang Guihong Han School of Chemical Engineering Zhengzhou UniversityZhengzhou 450001China Zhongyuan Critical Metals laboratory Henan ProvinceZhengzhou 450001China

solvent extraction,a separation and purification technology,is crucial in critical metal *** solvents commonly used in solvent extraction exhibit disadvantages,such as high volatility,high toxicity,and flammability,causing a spectrum of hazards to human health and environmental *** solvents have been recognized as potential alternatives to these harmful organic *** the past two decades,several neoteric solvents have been proposed,including ionic liquids(ILs)and deep eutectic solvents(DESs).DESs have gradually become the focus of green solvents owing to several advantages,namely,low toxicity,degradability,and low *** this critical review,their classification,formation mechanisms,preparation methods,characterization technologies,and special physicochemical properties based on the most recent advancements in research have been systematically ***,the major separation and purification applications of DESs in critical metal metallurgy were comprehensively ***,future opportunities and challenges of DESs were explored in the current research *** conclusion,this review provides valuable insights for improving our overall understanding of DESs,and it holds important potential for expanding separation and purification applications in critical metal metallurgy.

关键词： deep eutectic solvents preparations properties separation and purification critical metal metallurgy

Preparation of aldoxime through direct ammoximation using titanium silicalite-1 catalyst

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Chinese Journal of Chemical Engineering 2022年第7期35卷 11-17页

作者： Zhigang Xu Xiongfei Jin Tao Zhou Qian Zou Longcheng Liu zhongbo Wang Hanbing Sheng Huasheng Xie Hunan Provincial Key laboratory of Efficient and Clean Utilization of Manganese Resources College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China Kopperchem Industry Corp. LTDSolvent Extraction Engineering Research CenterChongqing 401221China Cangzhou Dahua Group Co. Ltd.Cangzhou 061000China

The liquid phase direct ammoximation of 5-isooctyl salicylaldehyde with ammonia and hydrogen peroxide was studied using titanium silicalite-1(TS-1)*** effect of reaction parameters on the yield of the product was studied,which include reaction temperature,reaction time,molar ratio of ammonia to aldehyde as well as hydrogen peroxide to *** influence of the amount of catalyst on the reaction results was also *** maximum 5-isooctyl salicylaldoxime yield of 98.76%was achieved under the following optimal reaction conditions:the molar ratio of 5-isooctylaldehyde to hydrogen peroxide and ammonia of 1:1.4:1.6,the reaction temperature of 70℃,the amount of TS-1 of 17.5 g·mol^(-1)(5-isooctyl salicylaldehyde),and the feeding time of 2 *** method has the mild reaction conditions and avoids the shortcomings of traditional ***,useless inorganic salts by-products are avoided,and there is no environmental pollution.

关键词： Titanium silicalite-1 Ammoximation Aldoxime Extractant Process optimization

Improving the reliability of classical molecular dynamics simulations in battery electrolyte design

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Journal of Energy Chemistry 2025年第2期101卷 34-41页

作者： Xin He Yujie Zhang Haomiao Li Min Zhou Wei Wang Ruxing Wang Kai Jiang Kangli Wang State Key laboratory of Advanced Electromagnetic Technology School of Electrical and Electronic Engineering Huazhong University of Science and Technology State Key laboratory of Materials Processing and Die & Mould Technology College of Materials Science and Engineering Huazhong University of Science and Technology Hubei Collaborative Innovation Center for High-efficiency Utilization of Solar Energy Hubei University of Technology

Explorations into new electrolytes have highlighted the critical impact of solvation structure on battery performance,Classical molecular dynamics(CMD) using semi-empirical force fields has become an essential tool for simulating solvation ***,mainstream force fields often lack accuracy in describing strong ion-solvent interactions,causing disparities between CMD simulations and experimental *** some empirical methods have been employed in some of the studies to address this issue,their effectiveness has been *** CMD research,supported by quantum chemical calculations and experimental data,reveals that the solvation structure is influenced not only by the charge model but also by the polarization *** empirical approaches that focused solely on adjusting ion-solvent interaction strengths overlooked the importance of polarization *** on this insight,we propose integrating the Drude polarization model into mainstream force fields and verify its feasibility in carbonate,ether,and nitrile *** experimental results demonstrate that this approach significantly enhances the accuracy of CMD-simulated solvation *** work is expected to provide a more reliable CMD method for electrolyte design,shielding researchers from the pitfalls of erroneous simulation outcomes.

关键词： Classical molecular dynamics Electrolyte Simulations Solvation structure