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Biogenic volatile organic compounds dominated the near-surface ozone generation in Sichuan Basin,China,during fall and wintertime

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Journal of Environmental Sciences 2024年第7期141卷 215-224页

作者： Dasheng Huang Qing Li Yan Han Shi-yong Xia Jiawei zhou Hanxiong Che Keding Lu Fumo Yang Xin Long Yang Chen Research Center for Atmospheric Environment Chongqing Institute of Green and Intelligent TechnologyChinese Academy of SciencesChongqing 400714China Chongqing Institute of Green and Intelligent Technology Chinese Academy of SciencesChongqing 400714China College of Resources and Environment Chongqing SchoolUniversity of the Chinese Academy of Sciences(UCAS Chongqing)Chongqing 400714China College of Environmental and Chemical Engineering Chongqing Three Gorges UniversityChongqing 404199China Key Laboratory for Urban Habitat Environmental Science and Technology School of Environment and EnergyPeking University Shenzhen Graduate SchoolLishui RoadNanshan DistrictShenzhen 518055China SKL-ESPC and BIC-ESAT College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China College of Architecture&Environment Sichuan UniversityChengdu 610065China

The complex air pollution driven by both Ozone(O_(3))and fine particulate matter(PM2.5)sig nificantly influences the air quality in the Sichuan Basin(SCB).Understanding the O_(3)for mation during autumn and winter is necessary to understand the atmospheric oxidative ***,continuous in-site field observations were carried out during the late summer,early autumn and winter of 2020 in a rural area of *** total volatile organic compounds(VOCs)concentration reported by a Proton-Transfer-Reaction Time-of Flight Mass Spectrometry(PTR-ToF-MS)were 13.66±9.75 ppb,5.50±2.64 ppb,and 9.41±5.11 ppb in late summer,early autumn and winter,*** anthropogenic VOCs(AVOCs)and biogenic VOCs(BVOCs)were 8.48±7.92 ppb and 5.18±2.99 ppb in late sum mer,3.31±1.89 ppb and 2.19±0.93 ppb in autumn,and 6.22±3.99 ppb and 3.20±1.27ppb in winter.A zero-dimensional atmospheric box model was employed to investigate the sensitivity of O_(3)-precursors by relative incremental reactivity(RIR).The RIR values of AV OCs,BVOCs,carbon monoxide(CO),and nitrogen oxides(NOx)were 0.31,0.71,0.09,and-0.36 for late summer,0.24,0.59,0.22,and-0.38 for early autumn,and 0.30,0.64,0.33 and-0.70 for winter,and the results showed that the O_(3)formation of sampling area was in the VOC-limited region,and O_(3)was most sensitive to BVOCs(with highest RIR values,>0.6)This study can be helpful in understanding O_(3)formation and interpreting the secondary formation of aerosols in the winter.

关键词： VOCs PTR-MS Model Ozone

Effect of V on high-temperature mechanical properties of Al-5Cu-1.5Ni alloy

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Journal of Iron and Steel Research International 2024年第7期31卷 1792-1810页

作者： Jun-ge Cui yong-bin Chen Xiang-zhou Fu Hai-long Yang Han-zhang Wang An-min Li Li-wen Pan School of Resources Environment and MaterialsGuangxi UniversityNanning 530004GuangxiChina State Key Laboratory of Featured Metal Materials and Life-Cycle Safety for Composite Structures Nanning 530004GuangxiChina Guangxi Higher Education Key Laboratory of Advanced Materials Nanning 530004GuangxiChina

The effects of V on microstructure,room temperature,and high-temperature(350℃)mechanical properties of Al-5Cu-1.5Ni alloy were *** results show that Al-5Cu-1.5Ni-xV alloys mainly compriseα-Al,Al_(2)Cu,Al_(3)(Ni,Cu)_(2),Al_(3)Ni,Al7Cu4Ni,and Al_(10)V *** addition of V can signally refineα-Al dendritic structure,which improves the mechanical properties of the as-cast alloys at room and high *** T6 heat treatment(540℃/12 h/WC+170℃/8 h/AC),α-Al,network skeleton structure Al_(3)(Ni,Cu)_(2),and Al_(10)V phases all show coarsening,while the fine nano-θ'-Al_(2)Cu precipitated from the matrix and dispersed *** introduction of V promotes the quantity of precipitatedθ'-Al_(2)Cu *** ultimate tensile strength of the heat-treated alloys at room and high temperatures is greatly improved compared to that of the as-cast *** highest high-temperature ultimate tensile strength of the alloys with V is 111.8 MPa,21.5%higher than that of the base *** analysis shows that the improvement of high-temperature mechanical properties after heat treatment is mainly due to the introduction of V,increasing the precipitated quantity of nano-θ'-Al_(2)Cu particles and improving its thermal *** dispersion strengthening effect ofθ'-Al_(2)Cu particles exceeds the weakening effect of other adverse microstructures on the mechanical properties.

关键词： Al-Cu-Ni-V alloy θ'-Al_(2)Cu phase Heat treatment Microstructure Mechanical property

A Semi-Mechanistic Model for Predicting the Service Life of Composite Coatings on VW63Z Magnesium Alloy

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1161-1176页

作者： Xiaoxue Wang Jingjing Guo Zihao Zeng Peng zhou Rongqiao Wang Xiuchun Liu Kai Gao Jingli Sun yong Yuan Fuhui Wang School of Energy and Power Engineering Beihang UniversityBeijing100191China Beijing Institute of Space Long March Vehicle Beijing100076China The School of Materials Science and Engineering Northeastern UniversityShenyang110819China The State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819China Shanghai Spaceflight Precision Machinery Institute Shanghai201600China

The application of Mg alloys is always accompanied by various coating technology, but a reliable model predicting the service life of coatings on Mg alloys is lacking but urgent. In this work, a semi-mechanistic model was proposed to predict the service life of plasma electrolytic oxidation (PEO) coating/electrophoretic coatings on a VW63Z Mg alloy;the model was decomposed into three parts: a first part depicting the degradation time of organic coating (L_(1)) and the diffusion time of electrolyte in the inorganic coating (L_(2)), respectively;a second part interpreting the breakdown of coatings due to the corrosion process (L_(3));a final part establishing an algorithm converting the accelerated tests into the real service environment (α);the effect of structural stress and dissimilar metal joints on the service life of coatings was also considered. Based on the ongoing accelerated experiments, the semi-mechanistic model could be able to predict the service life of both PEO coatings and composite coatings on VW63Z Mg alloy with a satisfiable precision.

关键词： Magnesium alloy Service life prediction Plasma electrolytic oxidation Electrophoretic coating Corrosion resistance

Proppant transport in rough fracture networks using supercritical CO_(2)

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Petroleum Science 2024年第3期21卷 1852-1864页

作者： yong Zheng Meng-Meng zhou Ergun Kuru Bin Wang Jun Ni Bing Yang Ke Hu Hai Huang Hai-Zhu Wang School of Petroleum Engineering Xi'an Shiyou UniversityXian710065ShaanxiChina Shaanxi Key Laboratory of Carbon Dioxide Sequestration and Enhanced Oil Recovery Xi'an710075ShaanxiChina State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing2249China School of Mining and Petroleum Engineering University of AlbertaEdmontonTG2W2AlbertaCanad Shaanxi Yanchang Petroleum(Group)Co. Ltd.Xi'an710075ShaanxiChina

Proppant transport within fractures is one of the most critical tasks in oil,gas and geothermal reservoir stimulation,as it largely determines the ultimate performance of the operating *** transport in rough fracture networks is still a relatively new area of research and the associated transport mechanisms are still *** this study,representative parameters of rough fracture surfaces formed by supercritical CO_(2) fracturing were used to generate a rough fracture network model based on a spectral synthesis *** fluid dynamics(CFD)coupled with the discrete element method(DEM)was used to study proppant transport in this rough fracture *** reveal the turning transport mechanism of proppants into branching fractures at the intersections of rough fracture networks,a comparison was made with the behavior within smooth fracture networks,and the effect of key pumping parameters on the proppant placement in a secondary fracture was *** results show that the transport behavior of proppant in rough fracture networks is very different from that of the one in the smooth fracture *** turning transport mechanisms of proppant into secondary fractures in rough fracture networks are gravity-driven sliding,high velocity fluid suspension,and fracture structure *** the same injection conditions,supercritical CO_(2)with high flow Reynolds number still has a weaker ability to transport proppant into secondary fractures than *** of the supercritical CO_(2)needs to be increased beyond a certain value to have a significant effect on proppant carrying,and under the temperature and pressure conditions of this paper,it needs to be increased more than 20 times(about 0.94 m Pa s).Increasing the injection velocity and decreasing the proppant concentration facilitates the entry of proppant into the branching fractures,which in turn results in a larger stimulated reservoir *** results help to understand the pro

关键词： Reservoir stimulation CCUS Rough fracture network Supercritical CO_(2) Proppanttransport

Flotation separation of feldspar from quartz using sodium fluosilicate as a selective depressant

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Rare Metals 2024年第3期43卷 1288-1300页

作者： Xin Hu Xian-Ping Luo Zi-Shuai Liu yong-Bing Zhang He-Peng zhou Zhi-Zhao Yang Xue-Kun Tang Faculty of Resource and Environmental Engineering Jiangxi University of Science and TechnologyGanzhou341000China Yichun Lithium New Energy Industry Research Institute Jiangxi University of Science and TechnologyYichun336000China

The physical and chemical properties of feldspar and quartz are highly similar,thus they cannot be easily separated *** this work,the flotation separation of feldspar from quartz using sodium fluosilicate(Na_(2)SiF_(6);SF)as a selective depressant was ***,the influence mechanism of SF on the selective flotation separation of feldspar and quartz was investigated via flotation tests,chemical analysis of flotation solution,Fourier transform infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XPS)and contact angle *** results of the flotation tests show that feld spar and quartz without SF treatment have good *** SF treatment,feldspar still has good floatability,whereas quartz has significantly reduced *** solution chemical analysis shows that the functional group plays an important role in depressing the quartz is[SiF_(6)]^(2-).FTIR,XPS and contact angle analysis results show that[SiF_(6)]^(2-)is adsorbed only on the surface of ***,a thin hydrophilic SiOF layer is generated on the surface,which interferes with the adsorption of the collector on the surface of the *** phenomenon leads to a significant reduction in quartz's ***,SF has a good ability to separate feldspar from quartz by flotation.

关键词： Flotation separation Depressants Sodium fluorosilicate Quartz Feldspar

Planet wind: Planetary evolution dominated by electromagnetic forces

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Science China Earth Sciences 2024年第10期67卷 3331-3336页

作者： yong WEI Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

1. Introduction Over the five centuries since Copernicus, the focus of planetary science has transitioned from the visible realm to the invisible. In the more than 60 years following the advent of the space age, our a... 详细信息

关键词： evolution dominated planetary

Risk factors for cognitive impairment in patients with chronic kidney disease

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World Journal of Psychiatry 2024年第2期14卷 308-314页

作者： Xiao-Hui Wang yong He Huan zhou Ting Xiao Ran Du Xin Zhang Department of Nephrology The Fifth Hospital of WuhanWuhan 430050Hubei ProvinceChina Department of Nephrology The Central Hospital of Enshi Tujia and Miao Autonomous PrefectureEnshi 445000Hubei ProvinceChina

BACKGROUND Chronic kidney disease(CKD)patients have been found to be at risk of concurrent cognitive dysfunction in previous studies,which has now become an important public health issue of widespread *** To investigate the risk factors for concurrent cognitive dysfunction in patients with *** This is a prospective cohort study conducted among patients with CKD between October 2021 and March 2023.A questionnaire was formulated by literature review and expert consultation and included questions about age,sex,education level,per capita monthly household income,marital status,living condition,payment method,and *** Logistic regression analysis showed that patients aged 60-79 years[odds ratio(OR)=1.561,P=0.015]and≥80 years(OR=1.760,P=0.013),participants with middle to high school education(OR=0.820,P=0.027),divorced or widowed individuals(OR=1.37,P=0.032),self-funded patients(OR=2.368,P=0.008),and patients with hypertension(OR=2.011,P=0.041)had a higher risk of cognitive *** risk of cognitive impairment was lower for those with a college degree(OR=0.435,P=0.034)and married *** The risk factors affecting cognitive dysfunction are age,60-79 years and≥80 years;education,primary school education or less;marital status,divorced or widowed;payment method,selffunded;hypertension;and CKD.

关键词： Cognitive impairment Cognitive dysfunction Chronic kidney disease

Review of the evolution and prevention of friction,wear,and noise for water-lubricated bearings used in ships

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Friction 2024年第1期12卷 1-38页

作者： Zhuo ZHANG Wu OUYANG Xingxin LIANG Xinping YAN Chengqin YUAN Xincong zhou Zhiwei GUO Conglin DONG Zhenglin LIU yong JIN Jinhua XIAO School of Transportation and Logistics Engineering Wuhan University of TechnologyWuhan 430063China Reliability Engineering Institute National Engineering Research Center for Water Transport SafetyWuhan 430063China School of Naval Architecture Ocean and Energy Power EngineeringWuhan University of TechnologyWuhan 430063China East Lake Laboratory Wuhan 420202China

With the development of green tribology in the shipping industry,the application of water lubrication gradually replaces oil lubrication in stern bearings and thrust *** terms of large-scale and high-speed ships,water-lubricated bearings with high performance are more strictly ***,due to the lubricating medium,water-lubricated bearings have many problems such as friction,wear,vibration,noise,*** review focuses on the performance of marine water-lubricated bearings and their failure prevention ***,the research of marine water-lubricated bearings is reviewed by discussing its lubrication principle,test technology,friction and wear mechanism,and friction noise generation *** performance enhancement methods have been overviewed from structure optimization and material ***,the potential problems and the perspective of water-lubricated bearings are given in detail.

关键词： water-lubricated bearings lubrication principles test techniques friction and wear friction noise evolution and prevention

Associations between the use of red yeast rice preparations and adverse health outcomes:An umbrella review of meta-analyses of randomized controlled trials

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Journal of Integrative Medicine 2024年第2期22卷 126-136页

作者： Zhen-yu Ma Shu-ping Yang Ying Li Tian-tian Xu Ya-lin Yang Hui-yong Yang Heng-bing Li Le-jin zhou yong Diao Su-yun Li School of Medicine Huaqiao UniversityQuanzhou 362021Fujian ProvinceChina College of Traditional Chinese Medicine Shandong University of Traditional Chinese MedicineJinan 250355Shandong ProvinceChina Second Clinical Medical College Nanjing Medical UniversityNanjing 211166Jiangsu ProvinceChina

Background:Red yeast rice(RYR),a natural lipid-lowering agent,is widely used in clinical ***,the existing meta-analyses concerning the safety of RYR preparations have yielded inconsistent results,and the credibility of the evidence has not been ***:This study was designed to evaluate the existing evidence and offer a comprehensive understanding of the associations between the use of RYR preparations and various adverse health *** strategy:Seven literature databases were searched from inception to May 5,2023,using medical subject headings and free-text terms(e.g.,“red yeast rice,”“Xuezhikang,”and“Zhibitai”).Inclusion criteria:Meta-analyses that investigated and quantitatively estimated associations between the use of RYR preparations and adverse health outcomes were included in this *** extraction and analysis:Two researchers independently extracted data using a standardized data collection table;any disagreements were resolved by consulting a third *** on the participant,intervention,comparator and outcome(PICO)framework in each eligible meta-analysis,a series of unique associations between the use of RYR preparations and adverse health outcomes were *** associations’effect estimates were re-evaluated using random-effect ***:Fifteen meta-analyses,comprising 186(164 unique)randomized controlled trials,were *** on A Mea Surement Tool to Assess Systematic Reviews version 2,3(20%)and 12(80%)of these meta-analyses had low and critically low confidence,respectively.A total of 61 unique associations between the use of RYR preparations and adverse health outcomes were extracted from eligible *** on the random-effect models,10(16.4%)associations indicated a significant protective effect of RYR preparations against adverse health outcomes,while 5(8.2%)indicated an increased risk of adverse health outcomes related to uric acid,alanine transaminase and aspartate trans

关键词： Red yeast rice Safety Adverse health outcomes Umbrella review Meta-analysis Systematic review