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Which is the determinant for cellulose degradation in cooperative ionic liquid pairs: dissolution or catalysis?

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Science China Chemistry 2016年第5期59卷 557-563页

作者： jinxing long Yangyu Zhang Lefu Wang Xuehui Li School of Chemistry and Chemical Engineering South China University of Technology College of Life Science and Technology Jinan University

Catalytic conversion of sustainable cellulose to the value-added chemicals and high quality biofuel has been recognized as a perfect approach for the alleviation of the dependence on the non-renewable fossil resources. Previously, we successfully de- signed and explored novel and efficient cooperative ionic liquid pairs for this renewable material, which has advantages of high reactor efficiency than current technologies because of the dissolution and in situ catalytic decomposition mechanism. Here, the determinant of this process is further studied by the intensive investigation on the relationship between the cellulose conversion and the properties of ionic liquid catalyst and solvent. Scanning electron microscope （SEM）, thermogravimetric analysis （TG） and elemental analysis were used for the comparative characterization of raw cellulose and the residues. The re- suits demonstrate that this consecutive dissolution and in situ catalysis process is much more dependent on the dissolution ca- pability of ionic liquid solvent, while comparatively, the effect of in situ acid catalysis is relatively insignificant.

关键词： cellulose ionic liquid dissolution in situ catalysis determinant

Application of chemometrics methods for the estimation of heavy metals contamination in river sediments

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Journal of Environmental Sciences 2005年第4期17卷 540-544页

作者： WANGYa-wei YUANChun-gang jinxing-long JIANGGui-bin StateKeyLaboratoryofEnvironmentalChemistryandEcotoxicology ResearchCenterforEco-EnvironmentalSciencesChineseAcademyofSciencesBeijing100085China

The concentration and speciation of six heavy metals in sediments of eight sampling sites of Haihe River were investigated. The metals, namely Cd, Cu, Co, Ni, Mn and Pb were considered. By using sequential extraction(SE), the total metals were divided into five fractions: exchangeable, carbonate bound, iron/manganese oxide bound, sulfides and organic matter fraction and residual fraction. A multivariate statistical approach(principal component analysis, PCA) was used to evaluate the contamination of heavy metals by the total levels and chemical forms, respectively. The results showed that the total metals concentration(TMC) could not provide sufficient and accurate information because the mobility, bioavailability and toxicity of metals depend not only on their total concentration but also on the physicochemical form in which they occur.

关键词： speciation heavy metal principal component analysis

Ionic liquids: Efficient solvent and medium for the transformation of renewable lignocellulose

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Science China Chemistry 2012年第8期55卷 1500-1508页

作者： long jinxing LI XueHui WANG LeFu ZHANG Ning State Key Laboratory of Pulp&Paper Engineering School of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhou 510640China Department of Chemistry Nanchang UniversityNanchang 330047China

Carbon-enriched lignocelluloses are regarded as the perfect alternative for nonrenewable fossil fuel, and have a great potential to alleviate the increasing energy crisis and climate change. However, the tightly covalent structure and strong intra and in- ter-molecular hydrogen bonding in lignoceUulose make it high recalcitrance to transformation due to the poor solubility in wa- ter or common organic solvents. Dissolution and transformation of lignocellulose and its constituents in ionic liquids have therefore attracted much attention recently due to the tunable physical-chemical properties. Here, ionic liquids with excellent dissolving capability for biomass and its ingredients were examined. The technologies for lignocellulose biorefining in the presence of ionic liquid solvents or catalysts were also summarized. Some pertinent suggestions for the future catalytic conver- sion and unitization of this sustained carbon-rich resource are proposed.

关键词： ionic liquids lignocellulose dissolution biorefinery

Synthesis and fluorescent properties of quinoxaline derived ionic liquids

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Green Energy & Environment 2022年第5期7卷 996-1005页

作者： Jiaqi Wu Lei Zhang jinxing long Qiang Zeng Biaolin Yin Xuehui Li School of Chemistry and Chemical Engineering Guangdong Provincial Key Lab of Green Chemical Product TechnologyState Key Laboratory of Pulp&Paper EngineeringSouth China University of TechnologyGuangzhou510640China

Ionic liquids(ILs) have attracted increasing attention since last few decades due to their high molecular design abilities and wide applications in different *** this study,four novel fluorescent isoquinolino [2,1-a]quinoxalin-5-ium ILs were designed and synthesized via a two-step process including a simple dual Schiff’s base formation and a subsequent [RhCp*Cl_(2)]_(2)-catalyzed oxidative C-H activation/annulation *** as-synthesized ILs were extensively characterized using FT-IR,~1 H-NMR,^(13)C-NMR,^(19)F-NMR,HSQC-NMR,HMBC-NMR and *** photophysical properties were determined by steady-state fluorescence *** results demonstrate that all these ILs showed dual or triple emissions,large stokes shift(90 nm) and mechanochromic *** on solvatochromism and titration experiments,it is thought that the emission bands of the ILs are raised from their local excited states,charge transfer states or excited state proton transfer of cations,while the substitute effect of these quinoxaline derived ILs on their stokes shifts is negligible.

关键词： spectroscopy reaction liquids

Simultaneous determination of 4-tert-octylphenol, 4-nonylphenol and bisphenol A in Guanting Reservoir using gas chromatography-mass spectrometry with selected ion monitoring

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Journal of Environmental Sciences 2004年第5期16卷 825-828页

作者： jinxing-long HUANGGuo-lan JIANGGui-bin ZHOUQun-fang LIUJmg-fu CollegeofEnvironmentalScienceandEngineering NankaiUniversityTianjin300071China ofEnvironmentalChemistryandEcotoxicology ResearchCenterforEco-EnvironmentalSciencesChineseAcademyofSciencesBeijing100085China

The wide occurrence of estrogenic compounds 4-tert-octylphenol, 4-nonylphenol, bisphenol A in surface water of Guanting Reservoir was successfully determined. The target compounds in water samples were preconcentrated by liquid-liquid extraction with dichloromethane, derivatized by trifluoroacetic anhydride, and quantified by gas chromatography-mass spectrometry(GC-MS) with selected ion monitoring(SIM). In the selected seven sampling sites(S1\_S7), the concentration of NP in sample S7 was significantly higher than the other in reservoir. The status of pollution in S3 and S7 were much more serious. The concentrations of OP, NP and BPA were in the range of 44.5—48.8, 221.6—349.6 and 30.2—82.7 ng/L, respectively. The pollutants were mainly inputted from the upper river and released from sediments in Guanting Reservoir.

关键词： 4-tert-octylphenol 4-nonylphenol bisphenol A Guanting Reservoir GC-MS-SIM

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稻谷千粒质量近红外光谱定量分析

农业机械学报 2009年第6期40卷 111-115,97页

作者：陈坤杰龙金星宋亮李克南京农业大学工学院南京210031

利用近红外漫反射光谱分析技术对稻谷千粒质量进行了测定和研究。通过对70个不同品种的稻谷样本进行近红外光谱扫描，将获得的光谱进行10种不同方法的预处理，然后应用PLS方法建立稻谷干粒质量预测的定标模型，根据交互验证决定系数（R... 详细信息

利用近红外漫反射光谱分析技术对稻谷千粒质量进行了测定和研究。通过对70个不同品种的稻谷样本进行近红外光谱扫描，将获得的光谱进行10种不同方法的预处理，然后应用PLS方法建立稻谷干粒质量预测的定标模型，根据交互验证决定系数（R0）和交互验证标准差（RMSECV）进行最佳定标模型选择，最后依据稻谷干粒质量预测值与真实值间的相关系数（r）和预测标准误差（SEP）进行模型预测能力评价。结果显示，在光谱区间11998．9～7497．9＋6101．7～5449．8＋4601．3～4246．5cm^-1、采用最小-最大归一化预处理方法建立的定标模型具有最大的交叉验证决定系数0．773和最小的均方根误差1．67g；以最佳定标模型预测的稻谷干粒质量与真实值之间的相关系数为0．945，预测标准误差为0．76g，表明近红外光谱分析技术可以用来进行稻谷干粒质量的快速测定。

关键词：稻谷千粒质量近红外光谱偏最小二乘法测定

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采用柔性支架处理GIS热胀冷缩的研究

高压电器 2017年第11期53卷 105-108页

作者：杨志轶龙金星思源电气股份有限公司上海201108

随着气体绝缘金属封闭开关设备(GIS)的广泛应用,经常会遇到母线较长的情况。尤其是户外安装的大电站,温差变化大,母线的热胀冷缩补偿尤其重要。文中以河南许昌长葛南变电站110 k V工程为例,对GIS母线进行热胀冷缩分析与计算,提出了一种... 详细信息

随着气体绝缘金属封闭开关设备(GIS)的广泛应用,经常会遇到母线较长的情况。尤其是户外安装的大电站,温差变化大,母线的热胀冷缩补偿尤其重要。文中以河南许昌长葛南变电站110 k V工程为例,对GIS母线进行热胀冷缩分析与计算,提出了一种采用柔性支架进行补偿的方法,采用有限元仿真方法对柔性支架的最大偏移量和强度进行计算。计算结果表明:采用柔性支架完全可以满足长直母线的热胀冷缩补偿要求,有效地保证了产品安全可靠运行。

关键词： GIS 母线柔性支架热胀冷缩

Photocatalytic activation of sulfite by N-doped porous biochar/MnFe_(2)O_(4) interface-driven catalyst for efficient degradation of tetracycline

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Green Energy & Environment 2024年第3期9卷 481-494页

作者： long Cheng Yuanhui Ji Jiangsu Province Hi-Tech Key Laboratory for Biomedical Research School of Chemistry and Chemical EngineeringSoutheast UniversityNanjing211189China

A novel photo-catalytic system composed of N-doped biochars(NBCs),MnFe_(2)O_(4) and sulfite activation under ultraviolet(NBCs/MnFe_(2)O_(4)/sulfite/UV)was constructed to realize the efficient eliminate of tetracycline(TC).As the carrier of MnFe_(2)O_(4),NBCs were synthesized from alfalfa,which has large specific surface area,graphite like structure and hierarchical porous *** adsorption isotherm indicated that NBCs/MnFe_(2)O_(4)-2:1 had the best adsorption performance for TC(347.56 mg g^(-1)).Through synergistic adsorption and photocatalysis,the removal rate of TC reached 84%,which was significantly higher than that of MnFe_(2)O_(4).Electrochemical impedance spectroscopy(EIS)and Photoluminescence(PL)characterization results showed that the introduction of NBCs improved the separation efficiency of photogenerated electron and hole pairs and enhanced the photocatalytic ***,the adsorption,degradation mechanism and degradation path of TC by the catalyst were systematically analyzed by coupling HPLC–MS measurement with the theoretical *** the advantages of excellent degradation performance,low cost,easy separation and environmental friendliness of NBCs/MnFe_(2)O_(4),this work was expected to provide a new path for the practical application of biochar.

关键词： Biochar MnFe_(2)O_(4) Sulfite Adsorption Photocatalysis

Prediction model for corrosion rate of low-alloy steels under atmospheric conditions using machine learning algorithms

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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 337-350页

作者： Jingou Kuang Zhilin long School of Civil Engineering Xiangtan UniversityXiangtan 411105China

This work constructed a machine learning(ML)model to predict the atmospheric corrosion rate of low-alloy steels(LAS).The material properties of LAS,environmental factors,and exposure time were used as the input,while the corrosion rate as the output.6 dif-ferent ML algorithms were used to construct the proposed *** optimization and filtering,the eXtreme gradient boosting(XG-Boost)model exhibited good corrosion rate prediction *** features of material properties were then transformed into atomic and physical features using the proposed property transformation approach,and the dominant descriptors that affected the corrosion rate were filtered using the recursive feature elimination(RFE)as well as XGBoost *** established ML models exhibited better predic-tion performance and generalization ability via property transformation *** addition,the SHapley additive exPlanations(SHAP)method was applied to analyze the relationship between the descriptors and corrosion *** results showed that the property transformation model could effectively help with analyzing the corrosion behavior,thereby significantly improving the generalization ability of corrosion rate prediction models.

关键词： machine learning low-alloy steel atmospheric corrosion prediction corrosion rate feature fusion