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衡水市三类臭氧重污染事件特征及其潜在源区研究

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环境生态学 2024年第5期6卷 120-126,133页

作者：陈瑞敏张玉婷韩冰赵孝伟田秀霞饶阳国家气候观象台河北饶阳053900 衡水市气象局河北衡水053000 邯郸市气象局河北邯郸056001

近年来,臭氧污染作为环境重要污染物之一,对人群健康和生态环境安全等方面构成严重威胁,备受关注。本研究利用2019—2021年衡水市生态环境局大气污染物监测数据和衡水气象站气象观测资料,对当地3类臭氧重污染事件的特征、气象条件、输... 详细信息

近年来,臭氧污染作为环境重要污染物之一,对人群健康和生态环境安全等方面构成严重威胁,备受关注。本研究利用2019—2021年衡水市生态环境局大气污染物监测数据和衡水气象站气象观测资料,对当地3类臭氧重污染事件的特征、气象条件、输送路径及潜在源区进行了对比研究。在污染特征方面,“类型1”和“类型2”的持续时间和污染强度强于“类型3”。究其成因可知,3类臭氧污染发生时大气环流背景的差异,是导致这3类臭氧污染事件对应的气象条件和演变机理呈现明显区别的关键原因。为了给当地生态环境部门关于臭氧污染生态效应科学应对政策的制定提供依据,本研究重点探究了3类臭氧污染事件潜在源区的特征。研究发现,3类臭氧污染事件地面均受低压控制,对流层低层处于暖气团或暖脊前部,对流层中层500 hPa受西北气流或偏西气流控制。3类事件的潜在源区主要分布在河南东部、安徽北部、江苏、山东西部及南部、河北东南部及渤海湾,并通过偏南和偏东路径输送到衡水,“类型1”潜在污染源区面积最大,污染最重,“类型2”次之,“类型3”最轻。本研究结果可为衡水市生态环境部门针对臭氧污染引发生态效应的预警预报及其科学评估提供科学参考。

关键词：臭氧污染气象条件后向轨迹潜在源区

河北南部PM_(2.5)和O_(3)复合污染的气象特征及天气分型

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四川环境 2024年第4期43卷 16-23页

作者：田秀霞陈瑞敏张珺谢祥永白樱樊泽薇邯郸市气象局河北邯郸056001 衡水市气象局河北衡水053000 饶阳国家气候观象台河北饶阳053900

为了解河北南部大气复合污染特征及其天气类型,利用2016—2022年环境监测、地面气象观测和NCEP再分析资料等,统计分析河北南部发生复合污染事件时的气象要素特征,并对地面气压场进行客观天气分型。结果表明,(1)2016—2022年期间河北南... 详细信息

为了解河北南部大气复合污染特征及其天气类型,利用2016—2022年环境监测、地面气象观测和NCEP再分析资料等,统计分析河北南部发生复合污染事件时的气象要素特征,并对地面气压场进行客观天气分型。结果表明,(1)2016—2022年期间河北南部复合污染占总污染天数4.0%;石家庄复合污染较多,且以O_(3)污染为主;复合污染较重的月份为4、7和9月。(2)复合污染期间,温度与O_(3)强正相关,与PM_(2.5)强负相关,海平面气压和相对湿度与O_(3)呈负相关,与PM_(2.5)呈弱正相关,水汽压、日照和能见度与O_(3)呈正相关,与PM_(2.5)呈弱负相关,风速与O_(3)和PM_(2.5)均为弱的负相关。(3)河北南部复合污染的天气类型主要有C型、W型、A型、U型,其中C型最多且偏O_(3)复合污染,W型、A型偏PM_(2.5)复合污染,U型以O_(3)和PM_(2.5)低浓度复合污染为主。研究显示,气象条件对复合污染影响显著,关注二者关系,对今后大气污染治理有一定指导意义。

关键词：复合污染气象特征 Lamb-Jenkinson环流分型

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Buckling optimization of curvilinear fiber-reinforced composite structures using a parametric level set method

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Frontiers of Mechanical Engineering 2024年第1期19卷 149-160页

作者： Ye tian Tielin SHI Qi xia State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China

Owing to their excellent performance and large design space,curvilinear fiber-reinforced composite structures have gained considerable attention in engineering fields such as aerospace and *** addition to the stiffness and strength of such structures,their stability also needs to be taken into account in the *** study proposes a level-set-based optimization framework for maximizing the buckling load of curvilinear fiber-reinforced composite *** the proposed method,the contours of the level set function are used to represent fiber *** a composite laminate with a certain number of layers,one level set function is defined by radial basis functions and expansion coefficients for each ***,the fiber angle at an arbitrary point is the tangent orientation of the contour through this *** the finite element of buckling,the stiffness and geometry matrices of an element are related to the fiber angle at the element *** study considers the parallelism constraint for fiber *** the sensitivity calculation of the objective and constraint functions,the method of moving asymptotes is utilized to iteratively update all the expansion coefficients regarded as design *** numerical examples under different boundary conditions are given to validate the proposed *** show that the optimized curved fiber paths tend to be parallel and equidistant regardless of whether the composite laminates contain holes or ***,the buckling resistance of the final design is significantly improved.

关键词： buckling optimization curvilinear fiber composite structure level set method manufacturing constraint

A super sandstorm altered the abundance and composition of airborne bacteria in Beijing

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Journal of Environmental Sciences 2024年第10期144卷 35-44页

作者： Fanxuan xia Zhuo Chen Enze tian Jinhan Mo Beijing Key Laboratory of Indoor Air Quality Evaluation and Control Department of Building ScienceTsinghua UniversityBeijing 100084China Songshan Lake Materials Laboratory Dongguan 523808China Institute of Physics Chinese Academy of SciencesBeijing 100190China College of Civil and Transportation Engineering Shenzhen UniversityShenzhen 518060China Key Laboratory of Coastal Urban Resilient Infrastructures(Shenzhen University) Ministry of EducationShenzhen 518060China Key Laboratory of Eco Planning&Green Building(Tsinghua University) Ministry of EducationBeijing 100084China

Sandstorm,which injects generous newly emerging microbes into the atmosphere covering cities,adversely affects the air quality in built ***,few studies have examined the change of airborne bacteria during severe sandstorm *** this work,we analyzed the airborne bacteria during one of the strongest sandstorms in East Asia onMarch 15th,2021,which affected large areas of China and *** characteristics of the sandstorm were compared with those of the subsequent clean and haze *** composition of the bacterial community of air samples was investigated using quantitative polymerase chain reaction(qPCR)and high-throughput sequencing *** the sandstorm,the particulate matter(PM)concentration and bacterial richnesswere extremely high(PM2.5:207μg/m3;PM10:1630μg/m3;5700 amplicon sequence variants/m3).In addition,the sandstorm brought 10 pathogenic bacterial genera to the atmosphere,posing a grave hazard to human *** the sandstorm subsided,small bioaerosols(0.65–1.1μm)with a similar bacterial community remained suspended in the atmosphere,bringing possible long-lasting health risks.

关键词： Airborne bacteria Sandstorm Bioaerosol Haze Pathogen

A dynamical neural network approach for distributionally robust chance-constrained Markov decision process

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Science China Mathematics 2024年第6期67卷 1395-1418页

作者： tian xia Jia Liu Zhiping Chen School of Mathematics and Statistics Xi’an Jiaotong UniversityXi’an710049China

In this paper,we study the distributionally robust joint chance-constrained Markov decision *** the logarithmic transformation technique,we derive its deterministic reformulation with bi-convex terms under the moment-based uncertainty *** cope with the non-convexity and improve the robustness of the solution,we propose a dynamical neural network approach to solve the reformulated optimization *** results on a machine replacement problem demonstrate the efficiency of the proposed dynamical neural network approach when compared with the sequential convex approximation approach.

关键词： Markov decision process chance constraints distributionally robust optimization moment-based ambiguity set dynamical neural network

Analysis on "96. 8" Heavy Rainstorm Process in Handan

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Meteorological and Environmental Research 2012年第8期3卷 18-23页

作者： ZHANG Yan-li YANG Xue-chuan WANG Ga SONG xiao-hui tian xiu-xia Shexian Meteorological Bureau in Hebei Province Shexian 056400China Handan Meteorological Bureau in Hebei Province Handan 056001China

[ ObjEtive] The research aimed to analyze ＂96.8＂ heavy rainstorm process causing flood disaster in Handan. [ Method] Based on ac- tual situation data, satellite cloud data and NCEP reanalysis data in the first dekad of August in 1996, ＂96.8＂ heavy rainstorm process causing flood disaster in Handan was analyzed to understand occurrence reason of the flood disaster. [ Result] Two meso-scale convective cloud clusters which developed and went north in turn caused ＂96.8＂ heavy rainstorm in Handan. Typhoon and inverted trough were main weather systems induced flood disaster in Handan. In going north process of the low-level jet, due to blocking of the subtropical high, water vapor and energy accumulated in Handan, providing material basis for formation of the heavy rainstorm. Development and eastward movement of the short-wave trough at middle lati- tude and continuous invasion of the reflux weak cold air at the low layer were direct reason for triggering generation and development of the convec- tive cloud cluster, and further causing continuous rainstorm. Wet layer over the rainstorm zone was deep and thick. Meridional distribution of the wet zone was wider than latitudinal distribution. South China Sea and Bay of Bengal were water vapor sources for the rainstorm zone. In the whole rain- storm period, it was convergence at low layer and divergence at high layer in the rainstorm zone. It was positive vorticity at low layer and negative vorticity at high layer. Precipitation intensity changed as convergence and divergence. Rainstorm zone had strong ascending motion. As strengthe- ning and uplifting of the ascending motion strong center, strong precipitation also strengthened. Rainstorm center was near the biggest vertical ve- locity center. Strong precipitation changed as vertical ascending motion. [ Conclmion] The research provided scientific basis for disaster prevention and reduction and decision-making service.

关键词： Heavy rainstorm No. 9608 strong typhoon Process analysis Handan China

Analyzing the surface passivity effect of germanium oxynitride:a comprehensive approach through first principles simulation and interface state density

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Nuclear Science and Techniques 2024年第5期35卷 74-84页

作者： Sheng-Jie Du xiu-xia Li Yang tian Yuan-Yuan Liu Ke Jia Zhong-Zheng Tang Jian-Ping Cheng Zhi Deng Yu-Lan Li Zheng-Cao Li Sha-Sha Lv College of Nuclear Science and Technology Joint Laboratory of Jinping Ultra‑Low Radiation Background Measurement of Ministry of Ecology and Environment Key Laboratory of Beam Technology of Ministry of Education Beijing Normal UniversityBeijing Normal UniversityBeijing 100875China Joint Research Center Nuctech Company LimitedBeijing 100084China Department of Engineering Physics Key Laboratory of Particle&Radiation Imaging of Ministry of EducationTsinghua UniversityBeijing 100084China Key Laboratory of Advanced Materials(MOE) School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

High-purity germanium(HPGe)detectors,which are used for direct dark matter detection,have the advantages of a low threshold and excellent energy *** surface passivation of HPGe has become crucial for achieving an extremely low energy *** this study,first-principles simulations,passivation film preparation,and metal oxide semiconductor(MOS)capacitor characterization were combined to study surface *** calculations of the energy band structure of the -H,-OH,and -NH_(2) passivation groups on the surface of Ge were performed,and the interface state density and potential with five different passivation groups with N/O atomic ratios were accurately analyzed to obtain a stable surface *** on the theoretical calculation results,the surface passivation layers of the Ge_(2)ON_(2) film were prepared via magnetron sputtering in accordance with the optimum atomic ratio *** microstructure,C-V,and I-V electrical properties of the layers,and the passivation effect of the Al/Ge_(2)ON_(2)/Ge MOS were characterized to test the interface state *** mean interface state density obtained by the Terman method was 8.4×10^(11) cm^(-2) eV^(-1).The processing of germanium oxynitrogen passivation films is expected to be used in direct dark matter detection of the HPGe detector surface passivation technology to reduce the detector leakage currents.

关键词： Surface passivation High purity germanium detector Germanium nitrogen oxide Interface state density

Pathological mechanism of immune disorders in diabetic kidney disease and intervention strategies

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World Journal of Diabetes 2024年第6期15卷 1111-1121页

作者： Tong Zhou Yi-Lin Fang tian-tian tian Gui-xia Wang Department of Endocrinology and Metabolism The First Hospital of Jilin UniversityChangchun 130021Jilin ProvinceChina Key Laboratory of Organ Regeneration and Transplantation of the Ministry of Education The First Hospital of Jilin UniversityChangchun 130021Jilin ProvinceChina National-Local Joint Engineering Laboratory of Animal Models for Human Diseases Jilin UniversityChangchun 130021Jilin ProvinceChina School of Public Health Jilin UniversityChangchun 130021Jilin ProvinceChina

Diabetic kidney disease is one of the most severe chronic microvascular complications of diabetes and a primary cause of end-stage renal *** studies have shown that renal inflammation is a key factor determining kidney damage during *** the development of immunological technology,many studies have shown that diabetic nephropathy is an immune complex disease,and that most patients have immune ***,the immune response associated with diabetic nephropathy and autoimmune kidney disease,or caused by ischemia or infection with acute renal injury,is different,and has a complicated pathological *** this review,we discuss the pathogenesis of diabetic nephropathy in immune disorders and the intervention mechanism,to provide guidance and advice for early intervention and treatment of diabetic nephropathy.

关键词： Diabetic kidney disease Immune disorders Pathological mechanism Intervention strategy Kidney damage Diabetic nephropathy Inflammasome Immunoglobulin

Growth,optical dispersion and magnetic behavior of Dy^(3+) doped yttrium iron garnet crystals

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Journal of Rare Earths 2024年第6期42卷 1110-1117,I0004页

作者： Yating Fang Hui Shen Yudie Ma Shijie Liao Shuang xia tian tian Ding Zhou Yunfeng Ma Jiayue Xu Institute of Crystal Growth School of Materials Science and EngineeringShanghai Institute of Technology National Engineering Center of Electromagnetic Radiation Control Materials School of Electronic Science and EngineeringUniversity of Electronic Science and Technology of China

Y_(3)Fe_(5)O_(12)(YIG)crystals are highly desirable for the fabrication of mid-infrared isolators with the rapid growth of optical communications,although it is rather challenging to grow large size and high-quality single ***^(3+)doping is expected to improve the optical and magneto-optical prope ***,high quality Dy:YIG crystals and the adjustment of Dy^(3+)on the structure and optical behavior of YIG crystal remain unclear,impeding its practical ***,a series of Y_(3-x)Dy_(x)Fe_(5)O_(12)(x=0,0.5,1.0,1.5,3)solid solution crystals was grown by the flux-Bridgman method and single crystals up to 25 mm were *** the introduction of Dy^(3+),lattice parameters are gradually enlarged from 1.2379 nm(YIG)to 1.2420 nm(DyIG).Typical Dy^(3+)absorption peaks are observed around 1070,1265 and 1670 *** refractive index decreases from 2.37(500 nm)to 2.10(2500 nm)for YIG crystal,and it reduces from 2.47(500 nm)to 2.16(2500 nm)for DyIG *** optical bandgaps remain almost unchanged for Dy:YIG *** optical dispersion of the refractive indices was finely fitted by the Wemple and DiDomenico(WDD)and the Sellmeier models,*** the increase of Dy^(3+)content,the saturation magnetization(Ms)decreases significantly from 23.62 emu/g(YIG)to 5.33 emu/g(DyIG).Small coercive field is persisted for this system,endowing small external magnetic *** results provide valuable references for the manipulation of rare earths on the properties of magnetooptical crystals,which is beneficial to the design of high-performance garnet crystals for the application of optical switching and non-reciprocal related devices.

关键词： Magneto-optical crystal Yttrium iron garnet Dy^(3+)doping Crystal growth Optical dispersion Rare earths