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Determination of the half-life of^(184g)Re and the isomeric ratio of^(184m,g)Re induced by D-T neutrons

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Chinese Physics C 2022年第11期46卷 168-176页

作者：兰长林魏玉婷王家豪杨宪林姜功葛裕杰徐超冯蠡李小军 School of Nuclear science and Technology Lanzhou UniversityLanzhou 730000China

The isomeric ratio of^(184m,g)Re and the half-life of^(184g)Re were measured in the ^(185)Re(n,2n)^(184)Re reaction at 14.8 MeV,and the uncertainty was discussed in detail.The measurements were performed using the activation method implemented for a rhenium sample using the K-400 neutron generator at the Chinese Academy of Engineering Physics(CAEP).Isomeric state and ground state nuclei of ^(184)Re were identified by their γ-ray spectra.To eliminate the effect of the γ-ray emitted from the isomer on the counting of the ground state characteristic peaks,the isomeric ratio of^(184m,g)Re was calculated to be 0.29±0.11 according to the neutron activation cross-section formula.This result is consistent with previous data within the uncertainty and can be used to determine parameters that characterize the dependence of the level density on the excitation energy and angular momentum.Through exponential function fitting and a detailed discussion of the uncertainty evaluation,the half-life of^(184g)Re was determined as 35.43±0.16 d,which is consistent with the currently recommended value;however,the uncertainty assessment of the latter was barely documented.In addition,this study indicates that the half-life of the ground state can be obtained by eliminating the contamination of γ-rays emitted from the isomer,which provides the possibility of determining the half-lives of nuclides containing isomers.

关键词： Half-life ^(184)Re γ-ray spectrometry isomeric ratio

VOC emitted by biopharmaceutical industries:Source profiles,health risks,and secondary pollution

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Journal of Environmental sciences 2024年第1期135卷 570-584页

作者： Jiawei Ma Lin Li State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of sciences Beijing 100049China national Engineering Laboratory for VOCs Pollution Control Material&Technology University of Chinese Academy of SciencesBeijing 101408China

The biopharmaceutical industry contributes substantially to volatile organic compounds(VOCs)emissions,causing growing concerns and social developmental conflicts.This study conducted an on-site investigation of the process-based emission of VOCs from three biopharmaceutical enterprises.In the workshops of the three enterprises,26 VOCs were detected,which could be sorted into 4 classes:hydrocarbons,aromatic hydrocarbons,oxygen-containing compounds,and nitrogen-containing compounds.Ketones were the main components of waste gases,accounting for 44.13%-77.85%of the overall VOCs.Process-based source profiles were compiled for each process unit,with the fermentation and extraction units of tiamulin fumarate being the main source of VOC emissions.Dimethyl heptanone,vinyl acetate,diethylamine,propylene glycol methyl ether(PGME),and benzene were screened as priority pollutants through a fuzzy comprehensive evaluation system.Ground level concentration simulation results of the Gauss plume diffusion model demonstrated that the diffusivity of VOCs in the atmosphere was relatively high,indicating potential non-carcinogenic and carcinogenic risks 1.5-2 km downwind.Furthermore,the process-based formation potentials of ozone and secondary organic aerosols(SOAs)were determined and indicated that N-methyl-2-pyrrolidone,dimethyl heptanone,and PGME should be preferentially controlled to reduce the ozone formation potential,whereas the control of benzene and chlorobenzene should be prioritized to reduce the generation of SOAs.Our results provide a basis for understanding the characteristics of VOC emission by biopharmaceutical industries and their diffusion,potentially allowing the development of measures to reduce health risks and secondary pollution.

关键词： Biopharmaceutical Volatile organic compound Priority pollutant Exposure risk Secondary pollution

Enhancement of heavy metals desorption from the soil by eddy deep leaching in hydrocyclone

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Journal of Environmental sciences 2024年第1期135卷 242-251页

作者： Ning Wang Hao Lu Bo Liu Tai Xiong Jianping Li Hualin Wang Qiang Yang School of Mechanical and Power Engineering East China University of Science and TechnologyShanghai 200237China national Engineering Laboratory for High Concentration Refractory Organic Wastewater Treatment Technology East China University of Science and TechnologyShanghai 200237China

An eddy deep leaching technology was developed in this paper to address the challenge of treating heavy metal contaminants in industrial mining areas.The desorption effect of As,Cd,Sb and Pb was investigated utilizing chemical leaching and physical eddy techniques.It was found that the heavy metals concentration increased with decreasing particle size.The highest proportion of Cd in the form distribution of soil was in the bound to iron and manganese oxides,while the maximum proportion of As,Sb and Pb were in the residual.The optimal solid-liquid ratio of the hydrocyclone was 1:20,and the corresponding separation efficiency and flow rate were 84.7%and 1.76 m^(3)/hr,respectively.The grade efficiency of soil particle separation increases with particle size and exceeds 99%for particles above 1,000μm.Leaching experiments have revealed that oxalic acid(OA)and a combination of oxalic acid and EDTA(OAPE)were more efficient than citric acid(CA)and a combination of citric acid and EDTA(CAPE)for the desorption of heavy metals,respectively.The comparison of OAPE and eddy leaching found that the latter improved the desorption efficiency by 9.4%,7.5%,7.2%and 7.8%for As,Cd,Sb and Pb compared to the former,respectively.The results demonstrated that the eddy leaching technique could further enhance the desorption efficiency of heavy metals.It is expected to provide technical support for soil remediation with reduced usage of leaching agents.

关键词： Heavy metals Soil remediation Oxalic acid Eddy leaching Hydrocyclone

Effect of reduction pretreatments on PdAg/Al_(2)O_(3) for HCHO and CO oxidation

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Journal of Environmental sciences 2023年第2期124卷 371-378页

作者： Liwei Meng Xue Han Lian Yu Yafei Wang Beijing Institute of Petrochemical Technology Beijing 102617China General Research Institute for Non-Ferrous Metals Beijing 100088China

PdAg/Al_(2)O_(3) were pretreated by CO and H2 reduction pretreatments,respectively.The reduced catalysts were tested for HCHO and CO oxidation and characterized by Brunner Emmet Teller(BET),X-ray diffraction(XRD),transmission electron microscopy(TEM),X-ray photoelectron spectroscopy(XPS)and oxygen temperature programmed desorption(O_(2)-TPD).These results indicate that the pretreatments have effect on PdAg reconstruction,PdAg particle size and active oxygen species,which are responsible for the catalytic performance.Compared with H2 reduction method,CO reduction is more suitable for PdAg/Al_(2)O_(3) pretreatment.PdAg/Al_(2)O_(3)-CO exhibited better catalytic performance.

关键词： PdAg Reduction method Catalytic oxidation CO

Optimized Electronic Modification of S-Doped CuO Induced by Oxidative Reconstruction for Coupling Glycerol Electrooxidation with Hydrogen Evolution

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Nano-Micro Letters 2023年第10期15卷 622-637页

作者： Ruo‑Yao Fan Xue‑Jun Zhai Wei‑Zhen Qiao Yu‑Sheng Zhang Ning Yu Na Xu Qian‑Xi Lv Yong‑Ming Chai Bin Dong china State Key Laboratory of Heavy Oil Processing College of Chemistry and Chemical EngineeringChina University of Petroleum(East China)Qingdao 266580People’s Republic of China

Glycerol(electrochemical) oxidation reaction(GOR) producing organic small molecule acid and coupling with hydrogen evolution reaction is a critical aspect of ensuring balanced glycerol capacity and promoting hydrogen generation on a large scale. However, the development of highly efficient and selective non-noble metal-based GOR electrocatalysts is still a key problem. Here, an S-doped CuO nanorod array catalyst(S-CuO/CF) constructed by sulfur leaching and oxidative remodeling is used to drive GOR at low potentials: It requires potentials of only 1.23 and 1.33 V versus RHE to provide currents of 100 and 500 mA cm^(-2), respectively. Moreover, it shows satisfactory comprehensive performance(at 100 mA cm^(-2), V_(cell) = 1.37 V) when assembled as the anode in asymmetric coupled electrolytic cell. Furthermore, we propose a detailed cycle reaction pathway(in alkaline environment) of S-doped CuO surface promoting GOR to produce formic acid and glycolic acid. Among them, the C–C bond breaking and lattice oxygen deintercalation steps frequently involved in the reaction pathway are the key factors to determine the catalytic performance and product selectivity. This research provides valuable guidance for the development of transition metal-based electrocatalysts for GOR and valuable insights into the glycerol oxidation cycle reaction pathway.

关键词： Glycerol oxidation reaction(GOR) Hydrogen evolution reaction(HER) CuO Oxidative reconstruction Electronic modification

三维互连炭材料/金属导热复合材料的研究进展（英文）

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新型炭材料(中英文) 2023年第5期38卷 804-824页

作者：关洪达何新波张子建张涛曲选辉北京科技大学新材料技术研究院北京科技大学广州新材料研究院

随着电子设备的产热不断攀升，在确保设备性能和寿命方面，高效散热已成为一个关键的技术问题，高的导热性通常取决于填料在复合材料中形成快速导热通道的能力。近年来，在复合材料中利用高导热性填料开发三维互连结构已成为一种很有前... 详细信息

随着电子设备的产热不断攀升，在确保设备性能和寿命方面，高效散热已成为一个关键的技术问题，高的导热性通常取决于填料在复合材料中形成快速导热通道的能力。近年来，在复合材料中利用高导热性填料开发三维互连结构已成为一种很有前途的方法。与传统的均匀分布和定向排列相比，填料的三维互连结构显著提高了复合材料的热导率。本文综述了三维互连结构的炭材料增强金属基导热复合材料的研究进展，讨论了复合材料的导热机理和导热模型，分析了提高复合材料导热性能的关键因素。本文通过回顾这些独特的构建三维互连炭材料网络的形式及其对复合材料导热性能的影响，旨在为进一步开发高性能金属基导热复合材料提供参考。

关键词：炭填料三维互连网络金属基复合材料导热性制备方法

QED effects on phase transition and Ruppeiner geometry of Euler-Heisenberg-AdS black holes

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Chinese Physics C 2022年第11期46卷 291-307页

作者：叶旭陈子青李明达魏少文 Lanzhou Center for Theoretical Physics Key Laboratory of Theoretical Physics of Gansu ProvinceSchool of Physical Science and TechnologyLanzhou UniversityLanzhou 730000China Institute of Theoretical Physics&Research Center of Gravitation Lanzhou UniversityLanzhou 730000China Academy of Plateau science and Sustainability Qinghai Normal UniversityXining 810016China

Considering the quantum electrodynamics(QED)effect,we study the phase transition and Ruppeiner geometry of Euler-Heisenberg anti-de Sitter black holes in the extended phase space.For negative and small positive QED parameters,we observe a small/large black hole phase transition and reentrant phase transition,respectively,whereas a large positive value of the QED parameter ruins the phase transition.Phase diagrams for each case are explicitly shown.Then,we construct the Ruppeiner geometry in thermodynamic parameter space.Different features of the corresponding scalar curvature are shown for both the small/large black hole phase transition and reentrant phase transition cases.Of particular interest is the additional region of positive scalar curvature,indicating a dominant repulsive interaction among black hole microstructures,for the black hole with a small positive QED parameter.Furthermore,universal critical phenomena are observed for the scalar curvature of Ruppeiner geometry.These results indicate that the QED parameter has a crucial influence on the black hole phase transition and microstructure.

关键词： black holes thermodynamics phase transition Ruppeiner geometry

Picomolar inhibitor of reverse transcriptase featuring significantly improved metabolic stability

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药学学报:英文版 2023年第7期13卷 3054-3066页

作者： Ya-Li Sang Christophe Pannecouque Erik De Clercq Shuai Wang Fen-Er Chen Department of Chemistry Engineering Center of Catalysis and Synthesis for Chiral MoleculesFudan UniversityShanghai 200433China Shanghai Engineering Center of Industrial Asymmetric Catalysis for Chiral Drugs Shanghai 200433China School of science Harbin Institute of Technology(Shenzhen)Shenzhen 518055China Rega Institute for Medical Research KU LeuvenLeuven B-3000Belgium

Considering the undesirable metabolic stability of our recently identified NNRTI 5(t1/2=96 min)in human liver microsomes,we directed our efforts to improve its metabolic stability by introducing a new favorable hydroxymethyl side chain to the C-5 position of pyrimidine.This strategy provided a series of novel methylol-biphenyl-diarylpyrimidines with excellent anti-HIV-1 activity.The best compound 9g was endowed with remarkably improved metabolic stability in human liver microsomes(t1/2=2754 min),which was about 29-fold longer than that of 5(t1/2=96 min).This compound conferred picomolar inhibition of WT HIV-1(EC50=0.9 nmol/L)and low nanomolar activity against five clinically drug-resistant mutant strains.It maintained particularly low cytotoxicity(CC50=264μmol/L)and good selectivity(SI=256,438).Molecular docking studies revealed that compound 9g exhibited a more stable conformation than 5 due to the newly constructed hydrogen bond of the hydroxymethyl group with E138.Also,compound 9g was characterized by good safety profiles.It displayed no apparent inhibition of CYP enzymes and h ERG.The acute toxicity assay did not cause death and pathological damage in mice at a single dose of 2 g/kg.These findings paved the way for the discovery and development of new-generation anti-HIV-1 drugs.

关键词： NNRTI HIV-1 DAPYs Picomolar Metabolic stability

金属有机骨架和共价有机骨架及其衍生物用于超级电容器电极材料的研究进展

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新型炭材料 2022年第1期37卷 109-135页

作者：王帅郭玉哲王芳霄周圣虎曾天宇董育斌山东师范大学化学化工与材料科学学院山东省高校化学成像功能化探针协同创新中心分子与纳米探针教育部重点实验室山东济南250014

金属有机骨架(MOFs)和共价有机骨架(COFs)是一系列结晶多孔材料。由于其高度有序的结构、高的表面积、可调的孔径和拓扑结构、富含氧化还原活性位点的连续骨架,MOFs和COFs及其衍生物在储能领域引起了广泛关注。为了制造高性能超级电容... 详细信息

金属有机骨架(MOFs)和共价有机骨架(COFs)是一系列结晶多孔材料。由于其高度有序的结构、高的表面积、可调的孔径和拓扑结构、富含氧化还原活性位点的连续骨架,MOFs和COFs及其衍生物在储能领域引起了广泛关注。为了制造高性能超级电容器电极,MOFs和COFs及其衍生物具有结构稳定性好、氧化还原活性位点丰富和电子导电性高等特征。本文回顾了近年来MOFs和COFs材料、MOFs和COFs与导电材料(导电聚合物、石墨烯、碳纳米管)的复合材料、MOFs和COFs衍生炭材料的设计策略,以及所得材料的物化特性、电容性能的研究进展,并介绍了结构和性能之间的关系。最后,提出了基于MOFs和COFs电极材料的挑战和前景。

关键词：金属有机骨架共价有机骨架杂化材料衍生炭超级电容器