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Quantification of Trace Amounts of Impurities in High Purity Cobalt by High Resolution Inductively Coupled Plasma Mass Spectrometry

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Chinese Chemical Letters 2006年第8期17卷 1077-1080页

作者： hua lin xie Xi Du NIE You Gen TANG Department of Chemistry Hunan Institute of Technology Hengyang 421008 School of Chemistry and Chemical Engineering Central south university Changsha 410083

An analytical method using high resolution inductively coupled plasma mass spectrometry （HR-ICP-MS） for rapid simultaneous determination of Be, Mg, Al, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Ge, As, Se, Mo, Ag, Cd, Sn, Sb, Ba, Pt, Au and Pb in high purity cobalt was described. Sample digestions were performed in closed microwave vessels using HNO3 and HCl. The matrix effects due to the presence of excess HCl and Co were evaluated. The usefulness of high mass resolution for overcoming some spectral interference was demonstrated. The optimum conditions for the determination was tested and discussed. Correction for matrix effects, Sc, Rh and Bi were used as internal standards. The detection limits is 0.003-0.57 μg/g, the recovery ratio is 92.2%-111.2%, and the RSD is less than 3.6%. The method is accurate, quick and convenient. It has been applied to the determination of trace impurities in high purity cobalt with satisfactory results.

关键词： High resolution inductively coupled plasma mass spectrometry high purity cobalt,trace impurities matrix effect spectral interference internal standards.

Encapsulation of bimetallic phosphides into graphitized carbon for pH-universal hydrogen evolution reaction

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Journal of Energy Chemistry 2021年第12期30卷 253-261,I0005页

作者： Jian Zhou Yibo Dou Tao He Xiang-Jing Kong lin-hua xie Jian-Rong Li Beijing Key Laboratory for Green Catalysis and Separation Faculty of Environment and LifeBeijing University of TechnologyBeijing 100124China

Exploring nonprecious electrocatalysts for water splitting with high efficiency and durability is critically ***,bimetallic phosphides are encapsulated into graphitized carbon to construct a C@NiCoP composite nanoarray using bimetallic metal-organic framework(MOF) as a self-sacrificial *** resulting C@NiCoP exhibits superior performance for pH-universal electrocatalytic hydrogen evolution reaction(HER),particularly representing a low overpotential of 46.3 mV at 10 mA cm^(-2) and Tafel slope of 44.1 mV dec^(-1) in alkaline *** structural characterizations combined with theoretical calculation demonstrate that tailored electronic structure from bimetal atoms and the synergistic effect with graphitized carbon layer could jointly optimize the adsorption ability of hydrogen on active sites in HER process,and enhance the electrical conductivity as *** addition,the carbon layer served as a protecting shell also prevents highly dispersed NiCoP components from agglomeration and/or loss in harsh media,finally improving the *** work thus provides a new insight into optimizing activity and stability of pH-universal electrocatalysts by the nanostructural design and electronic structure modulation.

关键词： Bimetallic phosphides Graphitized carbon Hydrogen evolution reaction MOF template Electronic structure

Matrix Effects and Behaviors of Elements in Oxalic Acid Medium by Inductively Coupled Plasma Mass Spectrometry

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Chinese Chemical Letters 2006年第7期17卷 945-948页

作者： hua lin xie Yu Jie LI Xi Du NIE Li Bo LI Department of Chemistry Hunan Institute of Technology Hengyang 421008 College of Chemistry and Chemical Engineering Central south University Changsha 410083

The influence of different concentration of oxalic acid matrix on elemental inductively coupled plasma mass spectrometry （ICP-MS） has been investigated. It has been proved that the sensitivity of analytes can be significantly enhanced by adding small amounts of oxalic acid medium with adjusted nebulizer flow-rate gas, especially for the elements with ionization potential between 9 and 11 eV. Oxalic acid, as an enhancement agent, can be used to compensate the signal depression caused by inorganic matrix and to improve the detection limits about two to eight times, for the hard-to-ionize elements in ICP-MS determination.

关键词： ICP-MS oxalic acid enhancement effect.

Seed-aided green synthesis of metal-organic frameworks in water

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Green Chemical Engineering 2023年第1期4卷 64-72页

作者： Hao-Tian An Xin Zhang Chen Dong Mu-Yao Lu Rui Li Yabo xie lin-hua xie Jian-Rong Li Beijing Key Laboratory for Green Catalysis and Separation and Department of Environmental Chemical Engineering Faculty of Environment and LifeBeijing University of TechnologyBeijing100124China

Green synthesis of metal-organic frameworks(MOFs)in water with alleviated environmental influence and reduced cost is an essential step to transfer laboratory MOFs research to industrial *** from the commonly used organic solvents to pure water encounters challenges of the poor solubility of organic linkers,slow reaction kinetics,and the formation of polymorphic *** far,a universal MOFs synthetic strategy in water system has yet to be *** study reports the seed-aided synthesis of eleven MOFs with diverse compositions and structures while pure water serving as *** corresponding reaction temperature and time of using this new strategy were reduced compared with original synthetic approaches,while the products maintain porous structure and high *** success of this strategy relies on the addition of parent MOFs as seeds which could promote crystallization process by skipping the time-consuming induction period and avoiding the formation of polymorphic impurities.

关键词： Metal-organic frameworks Carbon neutrality Coal bed methane Greenhouse gas Fossil fuel

Applications of metal–organic frameworks for green energy and environment: New advances in adsorptive gas separation, storage and removal

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Green Energy & Environment 2018年第3期3卷 191-228页

作者： Bin Wang lin-hua xie Xiaoqing Wang Xiao-Min Liu Jinping Li Jian-Rong Li Beijing Key Laboratory for Green Catalysis and Separation and Department of Chemistry and Chemical Engineering College of Environmental and Energy EngineeringBeijing University of Technology Research Institute of Special Chemicals Taiyuan University of Technology

The separation of gas molecules with similar physicochemical properties is of high importance but practically entails a substantial energy penalty in chemical industry. Meanwhile, clean energy gases such as H_2 and CH_4 are considered as promising candidates for the replacement of traditional fossil fuels. However, the technologies for the storage of these gases are still immature. In addition, the release of anthropogenic toxic gases into the atmosphere is a worldwide threat of growing concern. Both in academia and industry, considerable research efforts have been devoted to developing advanced porous materials for the effective and energy-efficient separation, storage, or capture of the related gases. In contrast to conventional inorganic porous materials such as zeolites and activated carbons, metal–organic frameworks(MOFs) are considered as a type of promising materials for gas separation and storage. In this contribution, we review the recent research advance of MOFs in some relevant applications, including CO_2 capture, O_2 purification, separation of light hydrocarbons, separation of noble gases, storage of gases(CH_4,H_2, and C_2 H_2) for energy, and removal of some gaseous air pollutants(NH_3, NO_2, and SO_2). Finally, an outlook regarding the challenges of the future research of MOFs in these directions is given.

关键词： Metal–organic frameworks Gas separation and storage Light hydrocarbon Harmful gas Air purification

Convergence analysis for complementary-label learning with kernel ridge regression

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Applied Mathematics(A Journal of Chinese Universities) 2024年第3期39卷 533-544页

作者： NIE Wei-lin WANG Cheng xie Zhong-hua School of Mathematics and Statistics Huizhou UniversityHuizhou 516007China School of Computer Science and Engineering Huizhou UniversityHuizhou 516007China

Complementary-label learning(CLL)aims at finding a classifier via samples with complementary *** data is considered to contain less information than ordinary-label *** transition matrix between the true label and the complementary label,and some loss functions have been developed to handle this *** this paper,we show that CLL can be transformed into ordinary classification under some mild conditions,which indicates that the complementary labels can supply enough information in most *** an example,an extensive misclassification error analysis was performed for the Kernel Ridge Regression(KRR)method applied to multiple complementary-label learning(MCLL),which demonstrates its superior performance compared to existing approaches.

关键词： multiple complementary-label learning partial label learning error analysis reproducing kernel Hilbert spaces

Tetraphenylethene-based hole transporting material for highly efficient and stable perovskite solar cells

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Science China Chemistry 2024年第6期67卷 2009-2015页

作者： Peng Wang Pei Yuan Chenghao Ge Rongjun Zhao lin xie Yong hua School of Materials and Energy Yunnan UniversityKunming650091China

2,2,7,7-Tetrakis-(N,N-di-p-methoxyphenylamine)-9,9-spirobifluorene(Spiro-OMeTAD)has been identified as the most widely used and effective hole transporting material(HTM)in perovskite solar cells(PSCs).However,the complicated multistep synthesis and low intrinsic hole mobility of Spiro-OMe TAD limit its commercialized ***,developing highly efficient HTMs with less synthetic steps becomes increasingly ***,understanding hot carriers transfer dynamics at the interface of perovskite layer and hole transport layer is crucial for further enhancing PSCs performance towards Shockley-Queisser limit,which still lacks full investigation to ***,a new HTM based on tetraphenylethene(WP1)was successfully synthesized by a simple one-step reaction *** was found that WP1-based HTM exhibits more matched energy level,higher hole mobility and conductivity than those of the control Spiro-OMe *** femtosecond transient absorption results reveal that the transfer rate of hot holes in perovskite/WP1 sample is four times higher than that of perovskite/Spiro-OMeTAD,thereby helping enhance the device ***,the efficiency of PSCs is enhanced to 24.04%(WP1)from 22.85%(Spiro-OMeTAD).Moreover,the un-encapsulated device prepared with WP1 exhibits better long-term stability,retaining 87%of its initial PCE value after storing for 72 days under air environment,while the reference device shows76%of its initial *** work indicates that simple tetraphenylethene-based organic small molecule could be a very promising HTM candidate for highly efficient PSCs,and gives some significant insights for understanding intrinsic hot carriers transfer dynamics in device.

关键词： tetraphenylethene hole transporting material perovskite solar cells mobility hot carrier

Influence of Electroshocking Treatment on Microstructure and Mechanical Properties of Ti-6.5Al-3.5Mo-1.5Zr-0.3Si Thin-Wall Specimen Manufactured by Laser Melting Deposition

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 145-158页

作者： Yan Wen Xuan Sun Jian Zhou Bingliang Liu Haojie Guo Yuxin Li Fei Yin Liqiang Wang Lechun xie lin hua Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan430070China Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan430070China Hubei Longzhong Laboratory Xiangyang441000China Shanghai Aircraft Manufacturing Co. Ltd.Commercial Aircraft Corporation of ChinaLtd.Shanghai201324China State Key Laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai200240China

In order to improve the properties of titanium alloys manufactured by laser melting deposition(LMD),the electroshocking treatment(EST)was proposed in this *** effects of EST on microstructure and mechanical properties of LMD Ti-6.5Al-3.5Mo-1.5Zr-0.3Si were *** results showed that the width of the heat affected band decreased and disappeared under the thermal and athermal effects of EST,resulting in the uniform *** the microstructure,theαlaths became coarser gradually,and the quantity ofα/βinterface was *** reduction of the quantity ofα/βinterface leads to make less resistant to dislocation,resulting in the reduction in hardness and *** discontinuous grain boundaryαphase and nucleationαcolony near grain boundary inhibited the crack propagation and improved the ***,EST can manipulate the microstructure and improve the mechanical properties of LMD titanium alloys.

关键词： Electroshocking treatment(EST) Laser melting deposition(LMD) Titanium alloy Microstructure Mechanical properties

Tuning hot carrier transfer dynamics by perovskite surface modification

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Chinese Chemical Letters 2024年第10期35卷 457-460页

作者： Chenghao Ge Peng Wang Pei Yuan Tai Wu Rongjun Zhao Rong huang lin xie Yong hua School of Materials and Energy Yunnan UniversityKunming 650091China Department of Physics Center for Optoelectronics Engineering ResearchYunnan UniversityKunming 650091China

Understanding the role of perovskite surface passivators in hot carriers transfer dynamics is important to develop highly efficient perovskite solar cells(PSCs).In this work,we have designed and synthesized a naphthalimide-based organic small molecule(NCN)for perovskite surface defect *** reveal that the introduction of NCN not only reduces the density of perovskite defect-state,but also promotes hot carriers(HCs)cooling in perovskite through the transient absorption spectroscopy *** HCs cooling permits HCs transfer from perovskite layer into NCN layer,thus resulting in the decreased charge-carrier recombination in NCN-treated *** expected,the power conversion efficiency(PCE)of PSCs with NCN is enhanced to 22.02%from 19.95%for the control *** findings are relevant for developing highly efficient PSCs.

关键词： Perovskite solar cells Interface passivation Hot carrier Charge recombination Stability Naphthalimide