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中国激光 2019年第12期46卷 93-101页

作者：李旭文宋刚张兆栋刘黎明大连理工大学材料科学与工程学院辽宁省先进连接技术重点实验室

为了改善和提高不锈钢TIG电弧增材制造零件的成形质量和力学性能,加入小功率激光对TIG电弧进行诱导增强,对比激光加入前后的电弧形态,研究不同激光功率下制得的增材制造墙体的抗拉强度及微观组织。结果表明:激光的诱导作用能够压缩电弧... 详细信息

为了改善和提高不锈钢TIG电弧增材制造零件的成形质量和力学性能,加入小功率激光对TIG电弧进行诱导增强,对比激光加入前后的电弧形态,研究不同激光功率下制得的增材制造墙体的抗拉强度及微观组织。结果表明:激光的诱导作用能够压缩电弧,稳定堆积过程,提高堆积速度,实现墙体的低热输入堆积,提高墙体的力学性能;墙体的微观组织主要是柱状树枝晶;热量的积累使得墙体从下到上的枝晶间距逐渐增大,墙体从下到上的硬度值逐渐降低;墙体最顶部为等轴树枝晶;激光诱导电弧复合增材制造的316不锈钢墙体由奥氏体和铁素体组成。

关键词：激光技术增材制造 316不锈钢激光诱导电弧力学性能微观组织

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Facile synthesis of 3D N-doped porous carbon nanosheets as highly active electrocatalysts toward the reduction of hydrogen peroxide

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NANOSCALE 2018年第31期10卷 14923-14930页

作者： Lu, Nannan zhang, Tingting Yan, Xiaoyi Gu, Yue Liu, He Xu, Zhiqian Xu, Haixin Li, xuwen zhang, Zhiquan Yang, Ming Jilin Univ Coll Chem Changchun 130012 Jilin Peoples R China Jilin Univ Hosp 1 Dept Breast Surg Changchun 130012 Jilin Peoples R China

Constructing three-dimensional (3D) conductive frameworks with high specific surface areas and porous structures is indispensable for their applications as electrocatalysts. In this work, we illustrate for the first time that 3D N-doped porous carbon nanosheets (3D-NS), which are synthesized via a facile one-pot pyrolysis reaction using glucose and melamine as raw materials, can serve as high performance and green electrocatalysts for the reduction of H2O2. Moreover, a series of 3D-NS samples with a controllable content of nitrogen were obtained by adjusting the calcination temperature. From our research, the 3D-NS obtained at 900 degrees C possessed high specific surface areas, porous structures, proper dosages of N atoms, suitable degrees of graphitization and defects. Furthermore, we also illustrate their application in H2O2 electrochemical sensing in physiological environments. Under optimum conditions, the 3D-NS-based sensor displays a wide linear scope in the range of 0.5-14 000 mu M and a low detection limit of 0.18 mu M (S/N = 3). Therefore, with desirable selectivity, stability and anti-interference performance, the proposed sensor can be feasibly applied to detect H2O2 in human serum samples.

关键词： Electrocatalysts

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Discovering Dependence across Traffic Data of Disparate Regions Using Multiscale Generalized Correlation 2018

Discovering Dependence across Traffic Data of Disparate Regi...

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6th International Conference on Information Technology - IoT and Smart City (ICIT)

作者： Qiu, Dehong zhang, Pin Fang, Shaohong Lang, xuwen Feng, Hao Huazhong Univ Sci & Technol Sch Software Engn Wuhan Hubei Peoples R China Wuhan Coll Sch Informat Engn Wuhan Hubei Peoples R China

ISBN: (纸本)9781450366298

Deciphering potential associations between the traffic data of disparate regions is of great importance to urban traffic management. However, as the traffic data is structured, temporal and often high-dimensional, many traditional dependence testing approaches are not directly applicable. In this paper, we propose a new approach to test dependence between traffic data of disparate regions based on distance Correlation (dCorr) and Multiscale Generalized Correlation (MGC). The distance matrix between the structured traffic data of disparate regions is defined, which yields a consistent test statistic for testing dependence of traffic data. We conduct experiments on the real and simulated datasets. The results of our experiments demonstrate that the new approach can capture the complex dependence between the structured traffic data of disparate regions. Simultaneously, it requires a small number of samples and is computationally efficient.

关键词： Traffic management network dependence graph distance distance correlation multiscale generalized correlation

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基于药理学研究生教学实践考核体系的探索

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中华医学教育探索杂志 2021年第9期20卷 965-968页

作者：毛旭文张晓倩阿尔祖亚·多力空周文婷新疆医科大学药学院药理学教研室乌鲁木齐830011

教学实践是研究生培养过程中的重要环节,本文对目前研究生教学实践现状及存在的问题进行分析,探讨新的教学实践模式对研究生培养的影响。本文针对研究生教学实践存在的问题进行改革,从学科课程学习、教学准备、理论教学、实验教学参与... 详细信息

教学实践是研究生培养过程中的重要环节,本文对目前研究生教学实践现状及存在的问题进行分析,探讨新的教学实践模式对研究生培养的影响。本文针对研究生教学实践存在的问题进行改革,从学科课程学习、教学准备、理论教学、实验教学参与及教学管理参与五个环节实施改革方案,并评价改革实施效果。通过研究生教学实践改革,研究生的教学能力和社会竞争力得到了切实有效的提高。新的教学实践模式为我国高校研究生教学能力培养提供了新的思路与方法。

关键词：药理学研究生教学实践考核体系

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Electronic structure and quasiparticle state character in the ferromagnetic Kondo lattice CeNiSb2

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Physical Review B 2025年第24期111卷 245113-245113页

作者： Bo Wang xuwen He Wei Feng Dengpeng Yuan Yi Liu Xiangfei Yang Yulu He Qin Liu Qunqing Hao Jian Wu Yun zhang Zhengtai Liu Mao Ye Jishan Liu Shiyong Tan Qiuyun Chen Xinchun Lai Science and Technology on Surface Physics and Chemistry Laboratory Mianyang 621907 China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research Institute Chinese Academy of Sciences Shanghai 201210 China

In a heavy-fermion system, the competition between the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction and the Kondo effect determines the ground-state properties, including superconductivity, magnetic orderings, and non-Fermi-liquid states. However, the temperature-dependent development of this competition remains unclear, particularly within the framework of ferromagnetic ground states. Here, the electronic structure and heavy quasiparticle band properties are exhaustively studied in CeNiSb2, a prototypical ferromagnetic Kondo lattice, using high-resolution angle-resolved photoemission spectroscopy. Our measurements reveal the three-dimensional electronic structure and Fermi surface topologies in CeNiSb2. The discrepancy of the quasiparticle bands along the Γ-M direction indicates band-dependent hybridization between the f electrons and conduction electrons (c−f hybridization), which may arise from differences in the conduction-band properties. The intensity of the quasiparticle band increases monotonically with decreasing temperature and deviates from the Kondo-like behavior at low temperature. This evolution provides a comprehensive picture of how the RKKY interaction and the Kondo effect develop and influence the behavior of f electrons across the temperature range. Our experimental results offer a spectroscopic study of the quasiparticle band and its temperature-dependent evolution in CeNiSb2, which may be crucial for understanding the underlying physics in heavy fermion compounds.

关键词： Ultraviolet photoelectron spectroscopy

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Reaction Kinetics Study on the Heating Stage of the Shenhua Direct Coal Liquefaction Process

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ENERGY & FUELS 2015年第4期29卷 2244-2249页

作者： Shan, Xiangen Li, Kejian zhang, xuwen Jiang, Hongbo Weng, Huixin E China Univ Sci & Technol Res Inst Petr Proc Shanghai 200237 Peoples R China Natl Engn Lab Direct Coal Liquefact Shanghai 201108 Peoples R China

Direct coal liquefaction in the heating stage of Shenhua Shendong bituminous coal was carried out in a 0.01 t/d continuous tubular facility with iron catalyst and hydrogenated anthracene and wash oil as solvent at a residence time (t) of 3.56.5 min and a reaction temperature (T) of 340-450 degrees C. The results show that when t = 3.5 min and T = 340 degrees C, a cracking reaction of coal occurs, while the oil yield was almost zero. As the residence time and temperature each increase, coal conversion and product yield exhibit different change patterns. Especially when t = 6.5 min and T = 450 degrees C: under these conditions, the coal conversion and oil yield reached 83.67 and 52.27 wt?%, respectively. To investigate the liquefaction kinetics, a 8-lump reaction kinetic model which follow first-order irreversible reactions (r = k(i) dC/dt) was developed to estimate the rate constants. The results indicated that the model is perfectly valid for the heating stage, and the yield of oil and gas were mainly from coal other than preasphaltene (PAA).

关键词： Lipids Kinetic modeling Coal Liquefaction Polymerization kinetics

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大蒜提取物对小鼠肠道菌群调节作用研究

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新疆医科大学学报 2021年第10期44卷 1165-1170页

作者：贾世栋杨浩宋百灵张春子毛旭文新疆医科大学药学院乌鲁木齐830011 新疆医科大学第六附属医院药学部乌鲁木齐830011 埃乐欣药业有限公司乌鲁木齐830011 天然药物活性组分与释药技术重点实验室乌鲁木齐830011

目的探究蒜氨酸、大蒜辣素、大蒜粉对小鼠肠道菌群的调节作用。方法将100只小鼠分为:空白对照组(灌胃蒸馏水,灌胃剂量0.1 mL/10 g体质量),蒜氨酸低(0.0043 mg/g体质量)、中(0.0086 mg/g体质量)、高(0.0172 mg/g体质量)剂量组,大蒜辣素低... 详细信息

目的探究蒜氨酸、大蒜辣素、大蒜粉对小鼠肠道菌群的调节作用。方法将100只小鼠分为:空白对照组(灌胃蒸馏水,灌胃剂量0.1 mL/10 g体质量),蒜氨酸低(0.0043 mg/g体质量)、中(0.0086 mg/g体质量)、高(0.0172 mg/g体质量)剂量组,大蒜辣素低(0.0019 mg/g体质量)、中(0.0039 mg/g体质量)、高(0.0078 mg/g体质量)剂量组,大蒜粉低(0.1108 mg/g体质量)、中(0.2216 mg/g体质量)、高(0.4432 mg/g体质量)剂量组。灌胃30 d后,采用菌落计数法检测实验前后粪便中乳杆菌、双歧杆菌、肠杆菌、肠球菌、产气荚膜梭菌数量变化。K-B纸片扩散法检测蒜氨酸、大蒜辣素、大蒜粉对5种菌的抑菌作用。结果与对照组比较,给药30 d后蒜氨酸、大蒜辣素、大蒜粉组乳杆菌、双歧杆菌数量增加,产气荚膜梭菌数量减少,差异有统计学意义(P<0.01)。体外抑菌试验表明,肠球菌、产气荚膜梭菌对蒜氨酸均低敏;乳杆菌、双歧杆菌、肠杆菌对蒜氨酸均不敏。大蒜辣素、大蒜粉对肠球菌、肠杆菌、乳杆菌、产气荚膜梭菌具有抑菌作用,并呈现剂量依赖性;对双歧杆菌对均不敏。结论蒜氨酸、大蒜辣素、大蒜粉对肠道菌群具有有益的调节作用,是一种良好的天然有益于肠道菌群的食品。

关键词：蒜氨酸大蒜辣素大蒜粉肠道菌群益生

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Thallium contamination in farmlands and common vegetables in a pyrite mining city and potential health risks

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ENVIRONMENTAL POLLUTION 2019年 248卷 906-915页

作者： Liu, Juan Li, Nuo zhang, Weilong Wei, Xudong Tsang, Daniel C. W. Sun, Yubing Luo, xuwen Bao, Zhi'an Zheng, Wentao Wang, Jin Xu, Guoliang Hou, Liping Chen, Yongheng Feng, Yuexing Guangzhou Univ Key Lab Water Qual & Conservat Pearl River Delta Guangdong Prov Key Lab Radionuclides Pollut Contr Inst Environm Res Greater BaySch Environm Sci & Guangzhou 510006 Guangdong Peoples R China Guangzhou Univ Rural Nonpoint Source Pollut Comprehens Managemen Guangzhou 510006 Guangdong Peoples R China Hong Kong Polytech Univ Dept Civil & Environm Engn Hung Hom Kowloon Hong Kong Peoples R China North China Elect Power Univ Coll Environm Sci & Engn MOE Key Lab Resources & Environm Syst Optimizat Beijing 102206 Peoples R China Northwest Univ Dept Geol State Key Lab Continental Dynam Xian 710069 Peoples R China Guangzhou Univ Sch Life Sci Guangzhou 510655 Guangdong Peoples R China Univ Queensland Sch Earth & Environm Sci Brisbane Qld 4072 Australia

Thallium (Tl) is a trace metal of severe toxicity. Its health concerns via consumption of contaminated vegetables have often been overlooked or underestimated. This study was designed to gain insight into the actual level and distribution characteristics of Tl and metal (loid)s (Pb, Cd, Cr, Sb, Mn, Cu, Zn, Ni, and Co) in agricultural soils and common vegetables cultivated in different zones (upstream, midstream, and downstream) of a densely populated residential area in a typical mine city, which has been open-pit exploiting Tl-bearing pyrite minerals since 1960s. The results show that most of the agricultural soils exhibit contaminated levels of Tl, with Tl contents (upstream: 1.35-4.31 mg/kg, midstream: 2.43 -5.19 mg/kg, and downstream: 0.65-233 mg/kg) mostly exceeding the maximum permissible level (MPL) for agricultural land use (1 mg/kg). Sequential extraction procedure indicates that even Tl is predominantly retained in the residual fraction, significant levels of Tl are still present in the geochemically mobile fractions. Besides, metals like Cu, Cd, Mn, and Co are mostly distributed in the labile fractions. Almost all metal (loid)s in edible parts of the vegetables exceed their corresponding MPL for consumption. The chronic daily intake (CDI) and hazard quotient (HQ) values calculated for inhabitants at different ages indicate non-negligible Tl risks via consumption of local vegetables, especially for children. Therefore, it is critical to establish effective measures for hazardous waste management and enforceable regulations in Tl-polluted area to mitigate potential severe impacts of Tl on human health through food chain. (C) 2019 Elsevier Ltd. All rights reserved.

关键词： Thallium Agricultural soil Vegetable Metal/metalloid contamination Pyrite mining

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Centrifugation free and air-assisted liquid-liquid microextraction based on deep eutectic solvent for determination of rare ginsenosides in Kang'ai injection

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MICROCHEMICAL JOURNAL 2018年 142卷 313-320页

作者： Li, Peng Ye, Junfeng zhang, Yue Wang, Ziqi Ren, Sujuan Li, xuwen Jin, Yongri Jilin Univ Coll Chem Changchun 130012 Jilin Peoples R China Jilin Univ Hosp 1 Changchun 130012 Jilin Peoples R China

A simple, effective and convenient enrichment method coupled with high performance liquid chromatography (HPLC) was established for the analysis of rare ginsenosides in Kang'ai (KA) injection. Air assisted liquid-liquid microextraction was used in this work for the first time to determine the rare ginsenosides in KA injection. Deep eutectic solvent (DES) and tetrahydrofuran (THF) were specially selected as a novel green extraction solvent and an emulsified solvent, respectively. To remove the DES droplets, Fe3O4 nanoparticles were used. Therefore, centrifugation was free in this work, which can increase the efficiency of analysis procedure. Moreover, Fe3O4 nanoparticles were reusable. To achieve better extraction efficiency and enrichment factor, the experimental conditions have been optimized, including type and volume of DES and emulsified solvent, amount of Fe3O4 nanoparticles and inorganic salt, and pH value. Under the optimum extraction condition, the validation parameters show the limits of detection (LODs) are in the range from 10.2 ng/mL to 137.8 ng/mL and the limits of quantity (LOQs) are in the range from 55.5 ng/mL to 428.5 ng/mL. The recoveries of analytes range from 91.3% to 106.7% with the relative standard deviations (RSDs) ranging from 1.2% to 4.5%. The recommended approach was utilized to acquire the information of constituents in KA injection. Moreover, the results in this research could provide a study basis for further study of KA injection.

关键词： Deep eutectic solvent Liquid-liquid microextraction Rare ginsenosides Kang'ai injection HPLC

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Measurement of the cross sections for ²³⁸U(n, γ)²³⁹U reaction in the energy range of 14.1-14.8 MeV using neutron activation method

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RADIATION PHYSICS AND CHEMISTRY 2018年 152卷 125-128页

作者： Wang, Qiang Liu, Tong Qiu, Yijia Lan, Changlin Chen, Bingjun zhang, Qian Zhan, xuwen Fang, Kaihong Lanzhou Univ Sch Nucl Sci & Technol Lanzhou 730000 Gansu Peoples R China

The neutron capture reaction cross sections of U-238 were measured at the neutron energies of 14.1, 14.5 and 14.8 MeV using the activation method and off-line gamma-ray spectrometric technique. The induced gamma-ray activities were measured using a low background gamma ray spectrometer equipped with a high resolution HPGe detector. The excitation functions of the U-238(n, gamma)U-239 reaction were also calculated theoretically using the TALYS-1.8 program and are in general agreement with experimental data. The experimentally determined cross sections were compared with the data in the literature, and the evaluated data of ENDF/B-VIII.0, JENDL-4.0, and CENDL-3.1, as well as calculated results from TALYS-1.8.

关键词： Neutron activation method Cross section Off-line gamma-ray spectrometry U-238(n, gamma)(239)

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