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Synthesis of uniform hexagonal Ag nanoprisms with controlled thickness and tunable surface plasmon bands

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International Journal of Minerals,Metallurgy and Materials 2019年第6期26卷 796-802页

作者： xing Chen Xun Liu Kai huang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Lab of Green Recycling and Extraction of Metals University of Science and Technology BeijingBeijing 100083China

In this work,we synthesized monodispersed hexagonal Ag nanoprisms in high yields in a system of poly(vinylpyrrolidone)(PVP)in N-methylpyrrolidone(NMP).A blue shift occurred and was strongly dependent on the thickness of the uniform Ag nanoprisms,which had almost the same radial *** the Ag nanoprisms grew thicker,their in-plane dipole resonance peaks markedly shifted toward shorter wavelengths(i.e.,blue shift).PVP played a critical role of favoring vertical growth of the Ag nanoplates,preventing aggregation,and inducing the formation of Ag hexagonal nanoprisms(HNPs)through the transformation from thin Ag triangular nanoprisms(TNPs).Compared with similar previous research,the present study provides quite uniform Ag hexagonal nanoplates,which makes the blue shift related more solely and distinctly to the thickness of the Ag *** findings of this work provide a new perspective toward understanding the unique optical characteristics of Ag HNPs with different aspect ratios.

关键词： hexagonal nanoprisms silver nanoprisms blue shift thickness effect

Separation of light hydrocarbons with ionic liquids: A review

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Chinese Journal of Chemical Engineering 2019年第6期27卷 1374-1382页

作者： Yuqi huang Yuanbin Zhang Huabin xing College of Chemical and Biological Engineering Zhejiang University

Light hydrocarbons(C1–C4) are fundamental raw materials in the petroleum and chemical industry. Separation and purification of structurally similar paraffin/olefin/alkyne mixtures are important for the production of highpurity or even polymer-grade light hydrocarbons. However, traditional methods such as cryogenic distillation and solvent absorption are energy-intensive and environmentally unfriendly processes. Ionic liquids(ILs) as a new alternative to organic solvents have been proposed as promising green media for light hydrocarbon separation due to their unique tunable structures and physicochemical properties resulting from the variations of the cations and anions such as low volatility, high thermal stability, large liquidus range, good miscibility with light hydrocarbons, excellent molecular recognition ability and adjustable hydrophylicity/hydrophobicity. In this review, the recent progresses on the light hydrocarbon separation using ILs are summarized, and some parameters of ILs that influence the separation performance are discussed.

关键词： Ionic liquids Hydrocarbons Absorption Sepatation Solubility

Catalytic oxidation of ethyl acetate on Ce-Mn-O catalysts modified by La

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Rare Metals 2021年第3期40卷 547-554页

作者： Yi-Jie Lao xing-xing Jiang Ju huang Zhen Zhang xing-Yi Wang Lab for Advanced Materials Research Institute of Industrial CatalysisSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

La/Ce_(0.5)Mn_(0.5) catalysts prepared by wetness impregnation of Ce_(_(0.5))Mn_(_(0.5)) with La(NO_(3))_(3)(aq) were used in catalytic oxidation of ethyl *** by X-ray diffractometer(XRD),H2 temperature programmed reduction(H2-TPR),X-ray photoelectron spectroscopy(XPS) and Raman shows that La/Ce_(0.5)Mn_(0.5) catalysts have fluorite-like ***_(0.5)Mn_(0.5) catalyst presents high activity with T90(the temperature needed for 90% conversion) of 200℃,where ethyl acetate is almost completely converted into CO_(2).The conversion at 195℃ maintains at 80% for at least 100 *** intermediates were mainly ethanol and acetaldehyde whose amounts are below250 × 10^(-6) and 16 × 10^(-6),*** situ FTIR indicates that the modes of dissociative adsorption of ethyl acetate are related to surface oxygen species,which affect the stability of catalysts and the selectivity for ethanol and acetaldehyde intermediates.

关键词： Ethyl acetate Catalytic combustion Ceria Lanthanum Manganese

Segmented tubular synthesis of monodispersed microsized copper oxalate

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International Journal of Minerals,Metallurgy and Materials 2019年第4期26卷 460-466页

作者： Xun Liu xing Chen Kai huang School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing Key Lab of Green Recycling and Extraction of Metals University of Science and Technology Beijing

Monodispersed microsized copper oxalate particles were prepared in a segmented continuous flow tube reactor, and the effect of the main parameters such as organic additive agent, initial copper ions concentration, residence time, and segmented media on the final products were investigated experimentally. The obtained copper oxalate microsized particles were disc-like in the presence of citrate ligand,which was the shape inducer for the precipitated copper oxalate. Thermodynamic equilibrium diagrams of the Cu(Ⅱ)-oxalate-H_2O,Cu(Ⅱ)-oxalate-citrate-H_2O, and Cu(Ⅱ)-oxalate-EDTA-H_2O solution systems were drawn to estimate the possible copper species under the experimental conditions and to explain the formation mechanisms of copper oxalate particles in the segmented fluidic reactor. Both theoretical and experimental results indicated that the presence of chelating reagents such as citrate and EDTA had distinct effect on the evolution of particle shape. Air and kerosene were tested as media for the fluidic flow segmentation, and the latter was verified to better promote the growth of copper oxalate particles. The present study provides an easy method to prepare monodispersed copper oxalate microsized particles in a continuous scaling-up way, which can be utilized to prepare the precursor material for conductive inks.

关键词： segmented flow tube reactor copper oxalate powder monodispersed scaling-up shape inducer

Facile synthesis of flake-like dihydrate zinc oxalate particles

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International Journal of Minerals,Metallurgy and Materials 2019年第2期26卷 234-240页

作者： xing Chen Xin Liu Kai huang School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Global Energy Research Institute Future Science and Technology Park Beijing Key Lab of Green Recycling and Extraction of Metals University of Science and Technology Beijing

Monodispersed dihydrated zinc oxalate(ZnC_2O_4·2H_2O) particles with characteristic morphology were synthesized by aging a mixed solution of zinc nitrate(Zn(NO_3)_2) and sodium oxalate(Na_2C_2O_4) in the presence of a citrate ligand, with an average flat size of approximately 10–15 μm. The important parameters, including the solution pH values and the concentration of the zinc ions and citrate ligand, were investigated using a series of experiments. It is verified that the citrate ligand significantly affects the morphology of zinc oxalate particles, probably via its multiple roles of chelating, dispersing, and selective absorption. Thermodynamic equilibrium of the distribution of zinc species in an aqueous solution of Zn(Ⅱ)-citrate-oxalate-H_2O was estimated to explain the experimental results and to clarify the size and morphological evolution mechanism of the precipitated particles.

关键词： facile synthesis zinc oxalate flaky morphology citrate ligand one-pot synthesis

CO_2 long-term diffusive leakage into biosphere in geological carbon storage

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Chinese Science Bulletin 2014年第28期59卷 3686-3690页

作者： Qin-Yi Li qun Chen xing Zhang Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Engineering MechanicsTsinghua University

Prediction of CO2 leakage into biosphere is very important for risk assessment in geological carbon storage projects. Underground CO2 can be transported into biosphere through short term leakage due to fractures of wellbores or cap rocks, which has been extensively investigated, and long term leakage due to diffusion, which has few relevant studies. This paper presents a diffusive model for CO2 gradual leakage into biosphere during a long period after CO2 injection. First, the paper describes a general diffusive model with long term secondary trapping effects for CO2 fluxes from underground into biosphere. Secondly, a simplified one-dimensional model is presented and solved for the CO2 concentrations in groundwater. The results show that the groundwater CO2 concentration will reach the maximum value at about 50 th year after CO2 injection and then slowly decrease due to secondary trapping ***, the partition coefficient is the dominant parameter for predicting the groundwater CO2 concentration while the convective mass transfer coefficient plays an insignificant role.

关键词： CO2浓度扩散模型生物圈碳储存泄漏地质二氧化碳浓度质量传递系数

Investigation of Formation Process of the Chrome-free Passivation Film of Electrodeposited Zinc

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Chinese Journal of Aeronautics 2007年第2期20卷 129-133页

作者： ZHU Li-qun YANG Fei huang Hui-jie School of Materials Science and Engineering Beijing University of Aeronautics and Astronautics Beijing 100083 China

The feasibility was investigated to substitute chrome-free passivation treatment of electrodeposited zinc in a titanium bath for chromate passivation treatment. The formation mechanism of the chrome-free passivation film was further analyzed. The surface mor- phologies and the elemental compositions of the treated samples with varied immersion times were observed by scanning electron mi- croscopy （SEM） and determined by energy dispersion spectrometry （EDS）, respectively. The electrode potential of the sample surface was recorded in the film formation process. The changes of the electrode potential are in accordance with that of SEM and EDS of the sample surface. The results of X-ray photoelectron spectroscopy （XPS） show the chrome-free passivation film composed ofZnO, SiO2, TiO2, Zn4Si207（OH）2, and SrF2. The anode zinc dissolution and the local pH value increase due to the cathode hydrogen ion reduction process result in the formation of the chrome-free passivation film. The macro-images of the chrome-free passivation films formed on electrodeposited zinc show that the color of the film changes from blue to iridescence with the increase of the immersion times.

关键词： electrodeposited zinc chrome-free pasivation film film formation process

Community Smell Occurrence Prediction on Multi-Granularity by Developer-Oriented Features and Process Metrics

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Journal of Computer Science & Technology 2022年第1期37卷 182-206页

作者： Zi-Jie huang Zhi-Qing Shao Gui-Sheng Fan Hui-qun Yu xing-Guang Yang Kang Yang Department of Computer Science and Engineering East China University of Science and TechnologyShanghai 200237China Shanghai Key Laboratory of Computer Software Testing and Evaluating Shanghai 200237China Shanghai Engineering Research Center of Smart Energy Shanghai 200237China

Community smells are sub-optimal developer community structures that hinder *** studies performed smell prediction and provided refactoring guidelines from a top-down aspect to help community ***,refactoring smells also requires bottom-up effort from every ***,supportive measures and guidelines for them are not available at a fine-grained *** recent work revealed developers'personalities and working states could influence community smells'emergence and variation,we build prediction models with experience,sentiment,and development process features of developers considering three smells including Organizational Silo,Lone Wolf,and Bottleneck,as well as two related classes including smelly developer and smelly *** predict the five classes in the individual granularity,and we also generate forecasts for the number of smelly developers in the community *** proposed models achieve F-measures ranging from 0.73 to 0.92 in individual-wide within-project,time-wise,and cross-project prediction,and mean R2 performance of 0.68 in community-wide Smelly Developer *** also exploit SHAP(SHapley Additive exPlanations)to assess feature importance to explain our *** conclusion,we suggest developers with heavy workload should foster more frequent communication in a straightforward and polite way to build healthier communities,and we recommend community shepherds to use the forecasting model for refactoring planning.

关键词： community smell developer sentiment socio-technical analysis empirical software engineering

基于化学衍生化的质谱技术在脂质分析中的研究进展

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分析测试学报 2025年第1期44卷 73-81页

作者：黄龙会石幸玉谢海洲周婷华南理工大学生物科学与工程学院广东广州510006

脂质不仅是细胞膜的主要组成部分,还参与多种生命活动如能量存储、信号传导等,在生命体中发挥着重要作用。质谱以其高灵敏度、准确度和快速分析能力,在结构表征中表现出色,已成为脂质分析的核心技术。然而,由于脂质的结构多样性和高度... 详细信息

脂质不仅是细胞膜的主要组成部分,还参与多种生命活动如能量存储、信号传导等,在生命体中发挥着重要作用。质谱以其高灵敏度、准确度和快速分析能力,在结构表征中表现出色,已成为脂质分析的核心技术。然而,由于脂质的结构多样性和高度相似性,其质谱定性、定量分析仍然面临着诸多挑战。化学衍生化技术通过对脂质进行结构修饰,可以改善脂质的离子化效率,并提高质谱检测的灵敏度与选择性,有效促进脂质的结构鉴定和定量分析。近年来,化学衍生化与质谱技术的结合策略广泛应用于脂质分析。该文综述了近十年来基于化学衍生化的质谱技术在解析脂质精确结构、提高检测灵敏度和定量准确性,以及结合新型质谱应用中的研究进展。

关键词：脂质化学衍生化质谱结构表征