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FRONTIERS OF ENVIRONMENTAL SCIENCE & ENGINEERING 2024年第11期18卷 143页

作者： Tan, Lichao Xu, Keke zhang, Shengxin Tang, Fukai zhang, Mingzhu Ge, Feng zhang, Kegui Minist Ecol & Environm Peoples Republ China Nanjing Inst Environm Sci Nanjing 210042 Peoples R China Minist Ecol & Environm Peoples Republ China Key Lab Pesticide Environm Assessment & Pollut Con Nanjing 210042 Peoples R China

Glucocorticoids, which are one of the most extensively used steroid hormones, are typical endocrine disruptors. In recent years, glucocorticoids have been widely detected in surface waters such as rivers and lakes, but there are relatively few studies focusing on their ecological risk assessment. In this study, the pollution characteristics of seven glucocorticoids were studied in the Jiangsu section of the Yangtze River Basin, and ecological risk assessments were performed using the risk quotient method. The results showed that seven glucocorticoids were detected at different levels at eight sampling sites. Among these glucocorticoids, prednisone had the highest value of 238.27 ng/L in the wet season, with pollution levels significantly higher than those reported in other areas. The ecological risk evaluation showed that prednisone, prednisolone, dexamethasone, and hydrocortisone acetate all had risk quotient values greater than 1 in the studied water environment, posing a high ecological risk. This study provides a scientific foundation for the in-depth study of the pollution characteristics and ecological risk of glucocorticoids in water bodies in the Jiangsu section of the Yangtze River Basin.

关键词： Yangtze River Basin Glucocorticoids Pollution characteristics Ecological risk assessment

Controllable synthesis of hydrocarbon dispersible HZSM-5 nanocrystals for quasi-homogeneous catalytic cracking of n-dodecane

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Controllable synthesis of hydrocarbon dispersible HZSM-5 nan...

12-bit 2.6 GS/s RF DAC based on return-to-zero technology

第十六届全国分子筛大会

作者： Guozhu Liu Shiguo bao Li Wang Xiangwen zhang Key Laboratory for Green Chemical Technology of the Ministry of Education School of Chemical Engineering and Technology Tianjin University

＜正＞Hydrocarbon dispersible HZSM-5 nanocrystals were controllably synthesized with organofunctionalized seeds in view of in-situ limiting the nanocrystals growth and regualting surface *** excellent stable dispersion of the prepared HZSM-5 nanocrystal in hydrocarbon was confirmed by TEM and *** quasi-homogeneous catalytic cracking of

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The Journal of China Universities of Posts and Telecommunications 2019年第4期26卷 36-42页

作者： Li Xiaopeng Wang Zhigong zhang Yi zhang Youtao zhang Mi Institute of RF and OE ICs Southeast UniversityNanjing 210096China Nanjing Guobo Electronics Company Limited Nanjing 210016China Nanjing Electronic Devices Institute Nanjing 210016China National and Local Joint Engineering Laboratory of RF Integration and Micro-assembly Technology Nanjing 210046China College of Microelectronics Nanjing University of Posts and TelecommunicationsNanjing 210046China State Key Laboratory of Millimeter Waves Southeast UniversityNanjing 210096China Science and Technology on Monolithic Intergrated Circuits and Modules Laboratory Nanjing 210016China

A 12-bit 2.6 GS/s radio frequency digital to analog converter(RF DAC)based on 1 um GaAs heterojunction bipolar transistor(HBT)process is *** DAC integrates a 4:1 multiplexer to reduce the data rate of input ports,which greatly facilitates the *** core adopts 4+8 segmented current steering structure.R-2R ladder network is used for 8 least significant bit(LSB)to realize binary current weighting and thermometer coding is used for 4 most significant bit(MSB).Return-to-zero(RZ)technology is used to expand the effective bandwidth of DAC output to the third Nyquist *** proposed DAC has a better output power flatness and spurious-free dynamic range(SFDR).Compared to traditional DAC,measured results demonstrate that the output power of this RZ DAC is increased by 33 dB and the SFDR is enhanced by 27 dB near the second Nyquist band.

关键词： DAC RZ Nyquist band

Morphological study of atherosclerotic plaque and its application in vulnerability evaluation

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Science China(Physics,Mechanics & Astronomy) 2008年第7期51卷 867-872页

作者： SU HaiJun zhang PengFei CHEN WenQiang zhang Mei zhang Yun School of Mathematics Shandong UniversityJinan 250100China Key Laboratory of Cardiovascular Remodeling and Function Research Ministry of Education of China and Ministry of Health of ChinaShandong UniversityQilu HospitalJinan 250012China

The relationships between the morphological characteristics and the vulnerability of atherosclerotic plaque were analyzed theoretically and several suggestions were proposed to evaluate the plaque vulnerability. Valid... 详细信息

关键词： length thickness morphological index evaluation critical value

基于响应面模型和集成方法的数控机床整机优化

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组合机床与自动化加工技术 2018年第3期 14-18页

作者：张在房张佳翔上海大学机电工程与自动化学院上海200072

针对数控机床整机优化过程中的复杂性,提出了一种响应面模型与集成方法相结合的机床整机优化设计方法。对数控机床整机进行静动态仿真,通过模态试验验证仿真的可信度。采用哈莫雷斯试验设计方法,抽取设计空间的样本点并进行数值模拟和... 详细信息

针对数控机床整机优化过程中的复杂性,提出了一种响应面模型与集成方法相结合的机床整机优化设计方法。对数控机床整机进行静动态仿真,通过模态试验验证仿真的可信度。采用哈莫雷斯试验设计方法,抽取设计空间的样本点并进行数值模拟和分析计算,建立了整机质量、最大形变量、一阶固有频率、二阶固有频率和三阶固有频率关于整机9个设计变量的响应面模型。提出了基于粒子群算法的初次优化与基于协同优化算法的二次优化相结合的优化策略。先对响应面模型进行初次全局优化,得到Pareto最优解集。在最优解集的基础上再对响应面模型进行二次局部优化,获得最优设计方案。结果表明,优化方案的各项性能都得到了提升,仿真结果验证了优化方案的可信度。因此该优化方法适用于结构较复杂的机床整机的优化设计。

关键词：模态分析响应面模型粒子群算法协同优化

Morphology control and photocatalytic characterization of WO_3 nanofiber bundles

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Chinese Chemical Letters 2018年第9期29卷 1350-1354页

作者： Ying zhang Defeng zhang Xinyu Xu Bingsen zhang College of Chemistry Chemical Engineering and Environmental Engineering Liaoning Shihua University Shenyang National Laboratory for Materials Science Institute of Metal research Chinese Academy of Sciences

The design and fabrication of semiconductor photocatalysts have attracted much attention. Herein, the effect of pH value and soluble salt additives on crystal structure, morphology and photocatalytic properties of WO3 was investigated in detail. It was found that the phase structure of WO3 changed from monoclinic to hexagonal phase when pH value of the solution increased. The ultraviolet-visible absorption spectra show that the monoclinic and hexagonal WO3 had absorbance from 600 nm to the ultraviolet-visible region. Hexagonal WO3 with nanofiber bundle morphology was successfully synthesized through Na2SO4 and Zn（CH3COO）2.2H2O-assisted hydrothermal method when pH value was 0.8. It exhibits the highest photocatalytic efficiency and better than that of cubic-shaped rnonoclinic WO3. The shuttle-like hexagonal WO3 prepared at pH 1.4 gives much lower activity. The morphology is a decisive parameter for the photocatalytic properties of WO3.

关键词： Tungstic trioxide Microstructure Nanofiber bundles Hydrothermal method Photocatalytic activity

Large inverse and normal magnetocaloric effects in HoBi compound with nonhysteretic first-order phase transition

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Chinese Physics B 2022年第7期31卷 539-543页

作者： Yan zhang You-Guo Shi Li-Chen Wang Xin-Qi Zheng Jun Liu Ya-Xu Jin Ke-Wei zhang Hong-Xia Liu Shuo-Tong Zong Zhi-Gang Sun Ji-Fan Hu Tong-Yun Tong bao-Gen Shen School of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China Institute of Physics Chinese Academy of SciencesBeijing 100190China Laboratory of Magnetic and Electric Functional Materials and Applications The Key Laboratory of Shanxi ProvinceTaiyuan 030024China School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

HoBi single crystal and polycrystalline compounds with Na Cl-type structure are successfully obtained,and their magnetic and magnetocaloric properties are studied in *** temperature increasing,Ho Bi compound undergoes two magnetic transitions at 3.7 K and 6 K,*** transition temperature at 6 K is recognized as an antiferromagneticto-paramagnetic(AFM–PM)transition,which belongs to the first-order magnetic phase transition(FOMT).It is interesting that the Ho Bi compound with FOMT exhibits good thermal and magnetic ***,a large inverse and normal magnetocaloric effect(MCE)is found in Ho Bi single crystal in the H||[100]direction,and the positive?SMpeak reaches 13.1 J/kg·K under a low field change of 2 T and the negative?S_(M)peak arrives at-18 J/kg·K under a field change of5 *** excellent properties are expected to be applied to some magnetic refrigerators with special designs and functions.

关键词： magnetocaloric effect antiferromagnetic rare-earth compounds

主权与人权的双重诉求——陈序经主权思想述论

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湖北大学学报（哲学社会科学版） 2008年第1期35卷 67-73页

作者：张世保中南民族大学民族学与社会学学院湖北武汉430074

在中国近代政治思想史中,陈序经的主权论述是值得注意的。他的博士论文《现代主权论》对历史上各种主权理论进行了详细的论判。陈序经主权理论的最大特色就是主张主权可分论,这种主张导致他对个体主权的重视。但是,陈序经的主权可分论... 详细信息

在中国近代政治思想史中,陈序经的主权论述是值得注意的。他的博士论文《现代主权论》对历史上各种主权理论进行了详细的论判。陈序经主权理论的最大特色就是主张主权可分论,这种主张导致他对个体主权的重视。但是,陈序经的主权可分论与主权一元论不是时立的,他对国家主权也是极力维护的,可以把陈序经的主权思想表述为对主权与人权的双重诉求。

关键词：陈序经现代主权论主权人权

转型时期腐败和地方政府公共投资效率的关联分析

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财经论丛（浙江财经学院学报） 2005年第5期 51-57页

作者：张雷宝浙江财经学院财政与公共管理学院浙江杭州310012

运用寻租经济学的分析方法,本文对经济转型时期地方官员腐败和公共投资效率两者之间的内在关联进行了综合研究,结合中国情形进行简要的实证分析,指出基于转型时期有效监管制度的缺失,腐败对地方政府公共投资的规模效率、结构效率以及产... 详细信息

运用寻租经济学的分析方法,本文对经济转型时期地方官员腐败和公共投资效率两者之间的内在关联进行了综合研究,结合中国情形进行简要的实证分析,指出基于转型时期有效监管制度的缺失,腐败对地方政府公共投资的规模效率、结构效率以及产出效率都产生了不同程度的负面效应。也就是说,作为带有高成本特性的一种“暗税”,腐败租金的存在不仅会导致区域内私人投资偏离社会期望的适度投资率,也会人为增大区域公共投资规模、扭曲区域公共投资结构,并降低区域内公共投资的产出水平。

关键词：腐败地方政府公共投资效率

干酪乳酪杆菌zhang VBNC态在不同复苏基质中的代谢物组学研究

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中国乳品工业 2022年第12期50卷 4-9页

作者：包秋华王会莹张雨虹内蒙古农业大学乳品生物技术与工程教育部重点实验室农业农村部奶制品加工重点实验室内蒙古自治区乳品生物技术与工程重点实验室呼和浩特010018

利用超高效液相色谱-四级杆飞行时间质谱技术(UPLC-Q-TOF MS)检测分析了干酪乳酪杆菌zhang(Lacticaseibacillus casei zhang,*** zhang)VBNC态在液体MRS培养基、脱脂乳二种复苏基质中的代谢物差异。结果显示:在正离子和负离子模式下分... 详细信息

利用超高效液相色谱-四级杆飞行时间质谱技术(UPLC-Q-TOF MS)检测分析了干酪乳酪杆菌zhang(Lacticaseibacillus casei zhang,*** zhang)VBNC态在液体MRS培养基、脱脂乳二种复苏基质中的代谢物差异。结果显示:在正离子和负离子模式下分别检测到2735种和1717种代谢物质。采用Metaboanalyst 5.0及SIMCA 14.1软件对代谢物进行分析,结合P2和VIP≥1相结合的条件,共筛选出差异代谢物22种,归属于氨基酸、糖类、维生素、脂类和嘌呤类5大类,其中,甘氨酸、L-谷氨酰胺、低聚木糖和烟酰胺等18种代谢物在液体MRS培养基中的相对含量显著高于脱脂乳,其余4种(S-核糖基-L-高半胱氨酸、乳糖、核黄素和(R)-3-羟基丁酸酯)代谢物在脱脂乳中相对高些,并从成分角度研究分析了这些代谢物在*** zhang VBNC态复苏中的可能作用,为初步探讨*** zhang VBNC态的复苏机理提供了参考。

关键词：干酪乳酪杆菌zhang 活的非可培养态复苏代谢组学超高效液相色谱-四级杆飞行时间质谱