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Formation and distribution of disinfection by-products during chlorine disinfection in the presence of bromide ion

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Chinese Science Bulletin 2008年第17期53卷 2717-2723页

作者： LI Bo QU jiuhui LIU HuiJuan zhao Xu State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

The influences of contact time and pH value on the formation and distribution of four species of trihalomethanes and five species of haloacetic acids during chlorination in the presence of bromine were investigated. Results showed that the distribution of molar fraction of trihalomethanes varied with contact time due to the change of bromide ion concentration during chlorination. Most of the trihalomethanes comprising bromine-containing species and the favored products of the haloacetic acids were chlorine-containing species after 24 h of chlorination. The extent of bromine incorporation in trihalomethanes and haloacetic acids both decreased with time. The contact time also had influence on the formation rate of different species of haloacetic acids. The formation and distribution of trihalomethanes and haloacetic acids strongly depended on the chlorination pH value. All of the trihalomethanes species formation increased with the increase of pH value except the bromoform that had not been detected. The molar fraction of bromodichloromethane and dibromochloromethane containing bromine increased with pH value while chloroform without bromine decreased. Under the pH range studied in this experiment, the predominant haloacetic acids species were trichloroacetic acid and dichloroacetic acid which all decreased with the increase of pH value and the level of TCAA was higher than that of DCAA.

关键词：溴化物消毒余氯氯化作用饮用水处理

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锌白铜带材表面高温发黄问题的研究

热处理技术与装备 2024年第5期45卷 15-19页

作者：刘羽飞张希杰胡斐斐赵久辉江平华刘诚毅江西铜业集团铜板带有限公司江西南昌330096 江西江铜高精板带有限公司江西南昌330096

锌白铜具有优良的电磁屏蔽性能,被广泛应用于电磁屏蔽罩,但在实际使用过程中,需要通过高温钎焊实现与其他部件的连接,在钎焊过程中往往会出现高温发黄现象,影响产品的美观及使用特性。通过研究锌白铜高温发黄机理和清洗工艺、研磨工艺... 详细信息

锌白铜具有优良的电磁屏蔽性能,被广泛应用于电磁屏蔽罩,但在实际使用过程中,需要通过高温钎焊实现与其他部件的连接,在钎焊过程中往往会出现高温发黄现象,影响产品的美观及使用特性。通过研究锌白铜高温发黄机理和清洗工艺、研磨工艺、工作辊表面粗糙度以及成品退火工艺对高温发黄的影响,解决了锌白铜高温发黄问题。结果表明,采用合适的清洗介质浓度和研磨刷转速、较低的工作辊表面粗糙度及合适的成品退火工艺,可以保证锌白铜在300℃保温5 min后不发黄;将该技术推广应用于铜镍锡、铜镍硅和铜锡磷等需要高温钎焊的合金中,同样也可解决高温钎焊发黄问题。

关键词：锌白铜高温发黄粗糙度成品退火

Differences in both the structure and interaction of the crust and mantle on the eastern and western sides of the Ordos Block

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Science China Earth Sciences 2024年

作者： Yong CHEN Yifang CHEN jiuhui CHEN Biao GUO Yu LI Panpan zhao State Key Laboratory of Seismic Dynamics Institute of GeologyChina Earthquake Administration National Field Scientific Observatory for Continental Rift Valley Dynamics in Taiyuan Institute of Earthquake Forecasting China Earthquake AdministrationKey Laboratory for Earthquake Prediction

The Ordos Block, the western part of the North China Craton (NCC), has preserved most of its cratonic lithospheric roots during the destruction and modification of the NCC, and nowconnects two distinctly different tectonic units, i.e., the Tibetan Plateau (TP) to the west and the North China Plain to the east. It is important to studythe detailed crust-mantle structure of the Ordos Block and surroundings to understand the interactions between the Ordos and adjacent regions and the dynamics of the NCC evolution. In this study, the S-wave velocity structure at depths of 0–100 km along an E-W profile at around 36.5°N from the Qilian orogen (QLO) to the Trans-North China Orogen (TNCO) within the NCC was investigated by joint inversion of the receiver functions (RFs) and surface wave dispersion data from 104 broadband seismic stations deployed in the region under the ChinArray project (Phase Ⅱ and Phase Ⅲ). The image of discontinuity structures along the profile was further constructed by common conversion point stacking of RFs. The main results are as follows:(1) The depth of the Moho in the study region gradually decreases from west to east, being the deepest in the QLO, the second in the Ordos Block, and the shallowest in the TNCO. Local depression and uplift of the Moho are also identified beneath the Haiyuan fault zone and the Shanxi-Shaanxi rift system (SSR), respectively.(2) The crust-mantle structure displays obvious lateral heterogeneities among tectonic regions. A pronounced low-velocity anomaly is observed at depths of 20–40 km beneath the QLO and becomes weakened and thinned to the east, indicating that thickening of the mid-to-lower crust probably occurred in the QLO during the growth and lateral extrusion of the northeastern TP under the resistance of the NCC. The lithosphere-asthenosphere boundary beneath the TNCO is imaged at～90 km depth, which is significantly shallower than that beneath the Ordos *** observation suggests that the lithosphere of t

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Impacts of Comorbidity and Mental Shock on Organic Micropollutants in Surface Water During and After the First Wave of COVID-19 Pandemic in Wuhan (2019–2021), China

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Engineering 2024年第6期37卷 40-48页

作者： Jian zhao Jin Kang Xiaofeng Cao Rui Bian Gang Liu Shengchao Hu Xinghua Wu Chong Li Dianchang Wang Weixiao Qi Cunrui Huang Huijuan Liu jiuhui Qu Center for Water and Ecology State Key Joint Laboratory of Environment Simulation and Pollution ControlSchool of EnvironmentTsinghua UniversityBeijing 100084China Hubei Provincial Research Institute of Environmental Science Wuhan 430072China Key Laboratory of Drinking Water Science and Technology Research Centre for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Sanitary Engineering Department of Water ManagementFaculty of Civil Engineering and GeosciencesDelft University of TechnologyDelft 2600 GAThe Netherlands China Three Gorges Corporation Wuhan 430010China Vanke School of Public Health Tsinghua UniversityBeijing 100084China

The first pandemic wave of coronavirus disease 2019(COVID-19)induced a considerable increase in several antivirals and antibiotics in surface *** common symptoms of COVID-19 are viral and bacterial infections,while comorbidities(e.g.,hypertension and diabetes)and mental shock(e.g.,insomnia and anxiety)are ***,little is known about the long-term impacts of comorbidities and mental shock on organic micropollutants(OMPs)in surface ***,we monitored 114 OMPs in surface water and wastewater treatment plants(WWTPs)in Wuhan,China,between 2019 and *** pandemic-induced OMP pollution in surface water was confirmed by significant increases in 26 OMP *** increases in four antihypertensives and one diabetic drug suggest that the treatment of comorbidities may induce OMP ***,cotinine(a metabolite of nicotine)increased 155 times to 187 ngL1,which might be associated with increased ***,the increases in zolpidem and sulpiride might be the result of worsened insomnia and ***,it is reasonable to note that mental-health protecting drugs/behavior also contributed to OMP *** the observed OMPs,telmisartan,lopinavir,and ritonavir were associated with significantly higher ecological risks because of their limited WWTP-removal rate and high *** study provides new insights into the effects of comorbidities and mental shock on OMPs in surface water during a pandemic and highlights the need to monitor the fate of related pharmaceuticals in the aquatic environment and to improve their removal efficiencies in WWTPs。

关键词： Coronavirus disease 2019 Comorbidities Mental shock Micropollutant Surface water

连续挤压板尺寸对C19210合金产品组织和性能的影响

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锻压技术 2023年第12期48卷 157-162,169页

作者：赵久辉肖桥平周涛江西铜业集团有限公司江西南昌330096 江西铜业技术研究院有限公司江西南昌330096 中南大学材料科学与工程学院湖南长沙410083

研究了连续挤压板尺寸对C19210合金组织和性能的影响。通过对铸杆进行连续挤压,制备了3种尺寸的挤压板,对3种挤压板分别进行粗轧、时效和成品轧制,并通过金相显微镜和透射电镜观察挤压和轧制板材的微观组织,通过万能拉伸机、硬度计和涡... 详细信息

研究了连续挤压板尺寸对C19210合金组织和性能的影响。通过对铸杆进行连续挤压,制备了3种尺寸的挤压板,对3种挤压板分别进行粗轧、时效和成品轧制,并通过金相显微镜和透射电镜观察挤压和轧制板材的微观组织,通过万能拉伸机、硬度计和涡流电导仪检测力学性能和导电性能。实验结果发现,挤压板尺寸越大,连续挤压过程中变形产热越多,固溶效果越好,促使时效析出更小的第二相粒子,从而使制备的成品具备更小的晶粒尺寸、更高的力学性能和抗软化性能。相对小尺寸挤压板制备的成品,大尺寸挤压板制备的成品的抗拉强度由404.1 MPa提升至414.6 MPa,抗软化硬度由98.7 HV提升至102.3 HV。

关键词：连续挤压 C19210合金挤压板尺寸微观组织抗软化性能

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7050铝合金等温模锻坯料设计

锻压技术 2017年第4期42卷 8-13页

作者：赵久辉张劲陈明安邓运来中南大学材料科学与工程学院湖南长沙410083

设计合适的锻压坯料是保证锻压后锻件具有良好综合性能的基础,通过改进锻压坯料的尺寸来改善锻件各部位的变形程度以获得具有良好组织及性能的锻件。运用有限元模拟软件Deform-3D模拟联接轴等温模锻过程,对不同尺寸的坯料模拟等温锻造过... 详细信息

设计合适的锻压坯料是保证锻压后锻件具有良好综合性能的基础,通过改进锻压坯料的尺寸来改善锻件各部位的变形程度以获得具有良好组织及性能的锻件。运用有限元模拟软件Deform-3D模拟联接轴等温模锻过程,对不同尺寸的坯料模拟等温锻造过程,随着坯料在Z向厚度尺寸的增加,模锻后锻件的等效应变随之逐渐增加。选择成形效果较佳且模锻后锻件变形程度逐渐增加的锻压坯料进行实验。对热处理后的等温模锻件进行室温拉伸、硬度、电导率、疲劳以及金相实验检测。结果显示:对于横截面沿长轴突变的联接轴锻件,锻件各部位间性能差异较大;等温模锻后,变形程度大的锻件能够获得更好的微观组织和力学性能。

关键词：等温模锻 Deform-3D 7050铝合金联接轴锻件变形程度

不同工艺加工C19210合金带材的组织和性能

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铜业工程 2023年第4期 102-107页

作者：赵久辉周涛肖桥平江西铜业集团有限公司江西南昌330096 江西铜业技术研究院有限公司江西南昌330096 中南大学材料科学与工程学院湖南长沙410083

采用“半连续铸锭热轧及多道次冷轧和退火”与“铸杆连续挤压及多道次冷轧和退火”两种工艺制备了C19210合金带材。采用金相显微镜观察该合金带材的晶粒组织,采用万能拉伸机、硬度计和涡流导电仪测试其力学性能和导电性能。结果表明:连... 详细信息

采用“半连续铸锭热轧及多道次冷轧和退火”与“铸杆连续挤压及多道次冷轧和退火”两种工艺制备了C19210合金带材。采用金相显微镜观察该合金带材的晶粒组织,采用万能拉伸机、硬度计和涡流导电仪测试其力学性能和导电性能。结果表明:连续挤压工艺更利于细化晶粒,制备的带材折弯性能更优异;而热轧工艺制备的带材由于热轧过程固溶更充分,时效过程能析出更多的第二相,使得热轧工艺制备的带材力学性能、导电率和抗软化性能略优于连续挤压工艺。

关键词：热轧连续挤压力学性能导电率抗软化性能

Ag对C19210合金带材的微观组织和性能的影响

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铜业工程 2023年第3期 64-69页

作者：赵久辉郭祊鹤肖桥平江西铜业集团有限公司江西南昌330096 江西铜业技术研究院有限公司江西南昌330096 中南大学材料科学与工程学院湖南长沙410083

研究了添加0.1%Ag对Cu-0.1Fe-0.03P合金铸杆连续挤压、时效和冷轧后组织与性能的影响,采用金相显微镜OM观察了该合金带材的微观组织,采用万能拉伸机、硬度计和涡流导电仪测试了其力学性能和导电性能。结果表明,Ag元素的添加能细化铸杆... 详细信息

研究了添加0.1%Ag对Cu-0.1Fe-0.03P合金铸杆连续挤压、时效和冷轧后组织与性能的影响,采用金相显微镜OM观察了该合金带材的微观组织,采用万能拉伸机、硬度计和涡流导电仪测试了其力学性能和导电性能。结果表明,Ag元素的添加能细化铸杆及其连续挤压后的晶粒组织,能阻碍冷轧态带材时效过程中的快速软化。Cu-0.1Fe-0.03P合金添加0.1%Ag的铸杆制备的成品带材导电率大于80%IACS,抗拉强度由417.2 MPa提高至504.8 MPa,同时具备优异的折弯性能和抗高温软化性能。

关键词：连续挤压时效力学性能导电率抗软化性能

Fabrication and photoelectrocatalytic properties of nanocrystalline monoclinic BiVO_4 thin-film electrode

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Journal of Environmental Sciences 2011年第1期23卷 151-159页

作者： Bin Zhou jiuhui Qu Xu zhao Huijuan Liu State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Graduate University of Chinese Academy of Sciences Belling 100039 China

Monoclinic bismuth vanadate （BiVO4） thin film was fabricated on indium-tin oxide glass from an amorphous heteronuclear complex via dip-coating. After annealation at 400, 500, and 600℃, the thin films were characterized by X-ray diffraction, field emission scanning electron microscopy, X-ray photoelectron spectroscopy, and UV-Vis spectrophotometry. The BiVO4 particles on the ITO glass surface had a monoclinic structure. The UV-Visible diffuse reflection spectra showed the BiVO4 thin film had photoabsorption properties, with a band gap around 2.5 eV. In addition, the thin film showed high visible photocatalytic activities towards 2,4-dichlorophenol and Bisphenol A degradation under visible light irradiation 0. 〉 420 nm）. Over 90% of the two organic pollutants were removed in 5 hr. A possible degradation mechanism of 2,4-dichlorophenol were also studied.

关键词： BiVO4 thin film degradation of pollutants photoelectrochemical process