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Influence of inherent iron and oxygen concentrations on selenite sorption process using bentonite

Science China Chemistry 2017年第9期60卷 1258-1264页

作者： Jiangang He Xueling Qiao yanlin shi Yao Li Xiaoyu Yang Wanqiang Zhou Chunli Liu Beijing National Laboratory for Molecular Sciences Fundamental Science Laboratory on Radiochemistry&Radiation ChemistryCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

The oxygen concentration and inherent Fe in bentonite have a significant influence on the Se(IV) sorption process. In this study, the sorption of selenite on natural bentonite was investigated using a batch experiment method, and the distribution coefficient (Kd) values were obtained in the pH range from 2.0 to 10.0 under oxic/anoxic conditions. The Kdvalues always reached a maximum value at a pH of 4 under oxic conditions and at a pH of 8 under anoxic conditions; meanwhile, the Kdvalue under anoxic conditions was larger than the value under oxic conditions, especially in regard to the maximum Kdvalues. The oxygen conditions have a significant influence on the ratio of redox-sensitive Fe2+/Fe3+, which was closely related to the difference in the Kdvalues under both oxic/anoxic conditions. Ferric selenite and green rust could be responsible for the maximum Kdvalues under oxic/anoxic conditions. In the leaching experiments, we found that the Fe2+in bentonite could replace Mg2+and Al3+in the octahedral sheet. Spectroscopy methods, such as Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS) were used to characterize the surface properties of the samples after reaction. Overall, this study shows that the addition of Fe2+-containing materials into backfill/buffer materials under anoxic condition could enhance the sorption of79Se(IV). © 2017, Science China Press and Springer-Verlag GmbH Germany.

关键词： Bentonite Oxygen Sorption Spectroscopic analysis X ray absorption spectroscopy X ray diffraction

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Uranium sorption on oxyhydroxide minerals by surface complexation and precipitation

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Chinese Chemical Letters 2022年第7期33卷 3461-3467页

作者： Jingyi Wang Wanqiang Zhou yanlin shi Yao Li Dongfan Xian Ning Guo Chunli Liu Beijing National Laboratory for Molecular Sciences Fundamental Science Laboratory on Radiochemistry and Radiation ChemistryCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

During the chemical weathering of the uranium mill tailings,released uranium could be immobilized by the newly formed secondary minerals such as oxyhydroxides.A deeper understanding of the interaction between uranium and common oxyhydroxides under environmental conditions is *** this work,uranium sorption behaviors on Al-,Mn-and Fe-oxyhydroxide minerals(boehmite,manganite,goethite,and lepidocrocite)were investigated by batch *** showed that the uranium sorption on Al-oxyhydroxide behaved significantly differently from the other three *** sorption edge of the Mn-and Fe-oxyhydroxides located around pH 5,while the sorption edge of boehmite shifted about 1.5 pH unit to near *** sorption isotherms of uranium on manganite,goethite and lepidocrocite at pH 5.0 could be well fitted by the Langmuir *** of surface complexation,sorption on boehmite happened mainly by uranium-bearing carbonates and hydroxides precipitation as illustrated by the characterization *** carbonate and phosphate strongly affected the uranium sorption *** removal efficiency of uranium by boehmite exceeded 98%after three sorption-desorption cycles,indicating it may be a potential material for uranium removal and recovery.

关键词： Uranium mill tailings Oxyhydroxides Uranium sorption Surface complexation Surface precipitation

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Study on wear mechanism of CVD diamond graver for stone machining

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金刚石与磨料磨具工程 2009年第6期29卷 11-14页

作者： Zheng Yanbin Zhang Chunmei Jiang Zhigang Lv Xianyi shi yanlin National Laboratory of Superhard Materials Jilin University Changchun 130012 China Department of Foundation Jilin Business and Technology College Changchun 130062 China Changchun Bafang Diamond Science ＆ Technology Co. Ltd Changchun 130012 China

This paper presents a new kind of CVD diamond graver for stone machining. Taking granite as machining object,we studied influence of cutting speed,feed rate and depth of cut on tool life by means of variance analysis and regression analysis. The result indicated that cutting speed had a more remarkable effect on tool life; feed rate ranked the second; depth of cut had no significant influence on tool life. Scanning electron microscope (SEM) was used to observe wear morphologies of gravers. It was found that abrasive wear was the main wear mechanism.

关键词：金刚石刀具使用寿命磨损机制

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Multi-objective constructal design for quadrilateral heat generation body based on thermal-entransy theory and NSGA-Ⅱ

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Science China(Technological Sciences) 2024年第9期67卷 2777-2786页

作者： CHEN LinGen ZHU HongWei GE yanlin shi ShuangShuang FENG HuiJun Institute of Thermal Science and Power Engineering Wuhan Institute of TechnologyWuhan 430205China Hubei Provincial Engineering Technology Research Center of Green Chemical Equipment Wuhan 430205China School of Mechanical Electrical EngineeringWuhan Institute of TechnologyWuhan 430205China

Based on thermal-entransy theory, the multi-objective constructal design of quadrilateral heat generation body(HGB) with similar shapes of leaves is studied further. The relationship between the aspect ratio of quadrilateral HGB and average temperature difference based on thermal-entransy dissipation is compared with that between the aspect ratio of quadrilateral HGB and the maximum temperature difference(MTD). The relationship between a composite function, consisting of linear weighting sum of the average temperature difference and MTD, and aspect ratio is obtained, and the optimal aspect ratios under minimum composite function with different weighting coefficients are obtained. Using the NSGA-Ⅱ algorithm, the Pareto frontier containing a series of compromise results of average temperature difference and MTD is obtained, and optimization results are compared using the deviation index. There is no aspect ratio to make both MTD and average temperature difference reach the minimum, and the optimal aspect ratio under the minimum MTD is smaller than that under the minimum average temperature difference. The optimal aspect ratio is obtained by making the composite function reach the minimum, and the optimal aspect ratios obtained by minimizing the composite function with different weighting coefficients are different. Compared with the construct of the initial design, the value of the composite function with optimal construct decreases by 1.9%, and the aspect ratio of the quadrilateral HGB decreases by 9.1%. The average temperature difference with the optimal construct increases by 2.1%, and the MTD with the optimal construct decreases by 5.6%. The deviation index under multi-objective optimization is smaller than that under single-objective optimization, and the obtained construct has better comprehensive thermal conductivity. Compared with TOPSIS and LINMAP decision-making methods, the average temperature difference with composite function optimization increases by 0.5

关键词： thermal-entransy theory constructal theory heat conduction quadrilateral heat generation body composite function NSGA-Ⅱ

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黑龙江省2011—2020年国家典型水土保持监测点数据分析

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水利科学与寒区工程 2024年第6期7卷 97-100页

作者：周宁孙和强李超刘凤飞史彦林樊华黑龙江省水利科学研究院黑龙江哈尔滨150070 黑龙江省水利学会黑龙江哈尔滨150070 黑龙江省水土保持重点实验室黑龙江哈尔滨150070

以2011—2020年《黑龙江省水土保持公报》发布的国家典型水土保持监测点数据为研究对象,计算径流小区侵蚀量多年平均减少率,定性分析不同措施控制土壤侵蚀效果,并采取统计学方法进行相关性分析,结果表明:地埂植物带、栽植灌木、自然恢... 详细信息

以2011—2020年《黑龙江省水土保持公报》发布的国家典型水土保持监测点数据为研究对象,计算径流小区侵蚀量多年平均减少率,定性分析不同措施控制土壤侵蚀效果,并采取统计学方法进行相关性分析,结果表明:地埂植物带、栽植灌木、自然恢复、免耕、秸秆还田措施可使土壤侵蚀强度降至微度,控制土壤侵蚀效果明显;免耕、秸秆还田、深松、横坡垄作和平播措施土壤侵蚀量多年平均减少率均在90%以上,具有水土保持作用和在农业生产实践中推广的价值。

关键词：水土保持监测水土保持措施水土流失治理黑龙江省

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Stressors and Coping Strategies of Medical Staff in the COVID-19 Pandemic in Wuhan

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International Journal of Mental Health Promotion 2021年第3期23卷 319-330页

作者： Long Liu yanlin shi Xiyan Fei Zhenzhen Wang Zhi Wang Li Li Lin Ding Qiaoyuan Yan College of Health Science and Nursing Wuhan Polytechnic UniversityWuhan430026China Wuhan Red Cross Hospital Wuhan430021China Optics Valley Hospital District of Wuhan Third HospitalWuhan430070China Hubei Provincial Hospital of Traditional Chinese Medicine Wuhan430068China Wuhan Hospital of Integrated Traditional Chinese and Western Medicine Wuhan430001China The Central Hospital of Wuhan Wuhan430004China Nursing Department of Union Hospital Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan430022China

Exploring whether medical staff perceive stress on the assigned medical tasks,what are the specific sources of stress,what are the tangible sources of support they expected to be helpful,and individual coping with stress to provide more accurate,personal support for psychological *** study uses a cross-sectional descriptive survey adopting convenience sampling among the medical staff who worked for over seven days in the infected areas of one Grade 2A and three Grade 3A hospitals during the COVID-19 *** assessment includes attitude when receiving tasks,major stressors,factors relieving stress,and personal management of stress.A total of 104(76.8%)valid questionnaires are received.A majority(94.3%)of the medical staff held a positive attitude taking duty for granted but feeling nervous and afraid(81.1%).Contacting the infected(90.6%)and compensation(92.5%)are the main *** major pressure sources are regarding safety for oneself(98.1%),colleagues(92.5%),and family(94.3%),as well as lack of effective treatment(92.5%),inadequate protective equipment(94.3%)and incomplete disinfection(94.3%).The main positive pressure adjustments include strict infection controlling measures(98.4%),maintaining a positive attitude(95.2%),actively attain more information 95.2%,and engage in recreational activities(93.6%),but more than 40%takes negative adjustments to vent their emotions and relieve anxiety,suggesting the importance of early psychological *** the COVID-19 pandemic,the main stressors among medical staff are safety,uncertainty and shortage of *** coping includes taking effective protective measures and achieving thorough understanding of the virus.

关键词： COVID-19 pandemics psychological stress medical staff

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Acute Effects of Exposure to Fine Particulate Matter and Its Constituents on Sex Hormone Among Postmenopausal Women — Beijing, Tianjin, and Hebei PLADs, China, 2018–2019

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China CDC weekly 2024年第13期6卷 249-253,I0001-I0004页

作者： yanlin Tian Jiaonan Wang Jianlong Fang Chen Chen Feng Zhao Yi Zhang Peng Du Yawei Li Wanying shi Yuanyuan Liu Enmin Ding Song Tang Xu Yue Xiaoming shi Chinese Research Academy of Environmental Sciences BeijingChina Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control(AEMPC)Nanjing University of Information Science&TechnologyNanjing CityJiangsu ProvinceChina China CDC Key Laboratory of Environment and Population Health National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijingChina Department of Epidemiology and Health Statistics School of Public HealthCapital Medical Universityand Beijing Municipal Key Laboratory of Clinical EpidemiologyBeijingChina National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijingChina

What is already known on this topic?Exposure to fine particulate matter(PM_(2.5))was linked to endocrine hormone disruption in the reproductive ***,it was unclear which specific components of PM_(2.5) were primarily responsible for these *** is added by this report?The study presented the initial epidemiological evidence that brief exposure to PM_(2.5) can elevate estradiol levels in postmenopausal *** particle components had unique effects,with watersoluble ions and specific inorganic elements like Ag,As,Cd,Hg,Ni,Sb,Se,Sn,and Tl potentially playing significant roles in increasing estradiol *** are the implications for public health practice?The study established that the prevalence of air pollution,along with its specific components,has been recognized as a novel risk factor affecting the balance of sex hormones.

关键词： pollution Particulate primarily

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基于AHP-CRITIC复合熵权法和灰色关联度分析的生地黄炒炭工艺优选

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亚太传统医药 2024年第5期20卷 23-30页

作者：谈小飞石炎林杨启永柯志华黄涅陈鹏黄海华汪文杰瞿彩丽劲牌持正堂药业有限公司/中药配方颗粒工程技术研究中心湖北黄石435100 湖北中医药大学药学院湖北武汉430072

目的:筛选生地黄炭的最佳炮制工艺参数,为生地黄炭质量控制提供综合评价模型。方法:以生地黄炭饮片6个有效成分(梓醇、地黄苷D、焦地黄苯乙醇苷A1、毛蕊花糖苷、异毛蕊花糖苷、5-羟甲基糠醛)的质量分数、吸附力、得率和外观性状评分共9... 详细信息

目的:筛选生地黄炭的最佳炮制工艺参数,为生地黄炭质量控制提供综合评价模型。方法:以生地黄炭饮片6个有效成分(梓醇、地黄苷D、焦地黄苯乙醇苷A1、毛蕊花糖苷、异毛蕊花糖苷、5-羟甲基糠醛)的质量分数、吸附力、得率和外观性状评分共9个评价指标,采用L_(9)(3^(4))正交试验设计和单因素考察,结合层次分析法(AHP)-指标权重确定方法(CRITIC)复合熵权确定各评价指标的权重系数,以直观分析、方差分析及复合熵权法结合灰色关联度分析法对正交试验结果进行综合评价,优选生地黄炭最佳炮制工艺。结果:优选的生地黄炭最佳炮制工艺参数为:温度200℃,炒制20 min,转速25 Hz。结论:AHP-CRITIC复合熵权法和灰色关联度分析法结合正交试验进行生地黄炭炮制工艺优化,各指标权重系数客观且真实,优选的炒炭工艺稳定可行,重复性良好,可以为生地黄炭炮制工艺标准及质量标准的建立提供试验依据。

关键词：生地黄炭吸附力正交试验设计 AHP-CRITIC复合熵权法灰色关联度分析

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Study about the Relationship Between Power-Train Modal and Connecting-Plane

Study about the Relationship Between Power-Train Modal and C...

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FISITA 2012 World Automotive Congress--Volume 13: Noise,Vibration and Harshness(NVH)

作者： Yongjiang Xu Zhangsong Zhan Wenjun Chen yanlin shi Hangkui Lu Junping Xue Xin Zhao Powertrain Global R&D Center in Chang an Automobile Co.Ltd State Key Laboratory ot vehicle NVH and Satety Technology

The power train modal is needed to pay attention because it is a main factor to affect *** relationship between power train modal and connecting plane was studied in this *** global vertical connecting plane is the main factor to affect power train global bend mode#l,especially the connecting plane between clutch box and engine *** a simple approximate model,and find the key factors affect the power train global bend mode#l with this *** key factors include connect stiffness ’K’,span distance ’L’ and inertia *** do several testing and CAE analysis,validated some methods to improve connect stiffness and power train *** last,applied these conclusions to optimize the modal of a 4 strokes L4 engine and improved the natural frequency of power train global bend mode#l from 198 to 254 *** study has gotten some useful conclusions,and these conclusions can be used to optimize power train global bend mode effectively.

关键词： Power-train Modal Engine Transmission Connecting-plane

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奥氏体不锈钢VOD冶炼过程中氮行为的研究

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铸造技术 2017年第6期38卷 1422-1425页

作者：时彦林张士宪河北工业职业技术学院材料工程系河北石家庄050091

建立了VOD精炼过程中氮行为的动力学模型,并进行了316L不锈钢控氮的实验室的热模拟试验。实验结果表明:钢中氮溶解度随氮分压的增大而增大,随温度降低而增大。渗氮速率随吹氮流量、氮分压增加而增大;初始氮含量越大,渗氮速率越小;温度... 详细信息

建立了VOD精炼过程中氮行为的动力学模型,并进行了316L不锈钢控氮的实验室的热模拟试验。实验结果表明:钢中氮溶解度随氮分压的增大而增大,随温度降低而增大。渗氮速率随吹氮流量、氮分压增加而增大;初始氮含量越大,渗氮速率越小;温度对于渗氮速率影响较小。钢中氮含量随吹氩时间、吹氩流量增加而降低;吹氩流量越大,脱氮速率越大。

关键词： 316 L不锈钢氮含量吹氩脱氮动力学

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