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Exploring drivers of the aggravated surface O_(3) over North China Plain in summer of 2015–2019: Aerosols, precursors, and meteorology

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Journal of Environmental Sciences 2023年第5期127卷 453-464页

作者： Shengju ou wei wei Shuiyuan Cheng Bin Cai Key Laboratory of Beijing on Regional Air Pollution Control Faculty of Environment and LifeBeijing University of TechnologyBeijing 100124China

Continuous aggravated surface O_(3) over North China Plain(NCP)has attracted widely public ***,we evaluated the effects of changes in aerosols,precursor emissions,and meteorology on O_(3) in summer(June)of 2015–2019 over NCP via 8 scenarios with WRF-Chem *** simulated mean MDA8 O_(3) in urban areas of 13 major cities in NCP increased by 17.1%∼34.8%,which matched well with the observations(10.8%∼33.1%).Meanwhile,the model could faithfully reproduce the changes in aerosol loads,precursors,and meteorological conditions.A relatively-even O_(3) increase(+1.2%∼+3.9%for 24-h O_(3) and+1.0%∼+3.8%for MDA8 O_(3))was induced by PM_(2.5) dropping,which was consistent with the geographic distribution of regional PM_(2.5) ***,the NO_(2) reduction coupled with a nearconstant VOCs led to the elevated VOCs/NOx ratios,and then caused O_(3) rising in the areas under VOCs-limited ***,the pronounced increases occurred in Handan,Xingtai,Shijiazhuang,Tangshan,and Langfang(+10.7%∼+13.6%for 24-h O_(3) and+10.2%∼+12.2%forMDA8 O_(3));while the increases in other citieswere 5.7%∼10.5%for 24-h O_(3) and 4.9%∼9.2%for MDA8 O_(3).Besides,the meteorological fluctuations brought about the more noticeable O_(3) increases in northern parts(+12.5%∼+13.5%for 24-h O_(3) and+11.2%∼+12.4%for MDA8 O_(3))than those in southern and central parts(+3.2%∼+9.3%for 24-h O_(3) and+3.7%∼+8.8%for MDA8 O_(3)).The sum of the impacts of the three drivers reached 16.7%∼21.9%,which were comparable to the changes of the observed O_(3).Therefore,exploring reasonable emissionsreduction strategies is essential for the ozone pollution mitigation over this region.

关键词： Surface ozone Driving force Aerosols Precursors Meteorology WRF-Chem model

Langmuir-Blodgett Films of C_(60)-end-capped Poly(ethylene oxide)

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Chinese Journal of Polymer Science 2019年第6期37卷 604-608页

作者： Ke ou Xian Xu Yu Shao wei-Jie Wang wen-Bin Zhang Shu-Guang Yang Center for Advanced Low-dimension Materials State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Material Science and Engineering Donghua University Key Laboratory of Polymer Chemistry&Physics of Ministry of Education Center for Soft Matter Science and Engineering College of Chemistry and Molecular Engineering Peking University

Buckyballs(C_(60)) are linked to one end and two ends of linear poly(ethylene oxide)(PEO) chains through highly efficient click chemistry to obtain giant amphiphilic molecules C_(60)-PEO and C_(60)-PEO-C_(60), respectively. C_(60)-PEO and C_(60)-PEO-C_(60) molecules are spread on water surface and then transferred to solid substrates with Langmuir-Blodgett(LB) film deposition approach. C_(60)-PEO and C_(60)-PEO-C_(60) exhibit fractal growth behavior on the solid substrate under certain conditions owing to the crystallization ability of PEO segment. PEO chain length and the end capped mode both affect the fractal growth pattern.

关键词： LB film Giant amphiphilic molecule Fractal growth

应用贝叶斯岭回归模型辨识水下航行器水动力系数研究

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海军工程大学学报 2025年第1期37卷 104-112页

作者：向国欧勇鹏陈君杰王威海军工程大学舰船与海洋学院武汉430033

针对水下航行器水动力系数求取问题,研究了应用贝叶斯岭回归模型进行水动力系数辨识的方法。首先,建立水下航行器六自由度运动模型并令其以指定方式运动,经白噪声调和、数据采样得到航行器空间运动仿真试验数据;然后,利用贝叶斯岭回归... 详细信息

针对水下航行器水动力系数求取问题,研究了应用贝叶斯岭回归模型进行水动力系数辨识的方法。首先,建立水下航行器六自由度运动模型并令其以指定方式运动,经白噪声调和、数据采样得到航行器空间运动仿真试验数据;然后,利用贝叶斯岭回归模型辨识获得一组新的水动力系数,并据此预报了航行器水平面Z形、回转运动;最后,通过与原模型的水动力系数、运动轨迹的对比分析发现:除敏感度不高的少数耦合项外,应用贝叶斯岭回归模型辨识水动力系数均具有良好的精度;相较于原模型,辨识所得一阶水动力系数偏差小于5%、二阶系数偏差小于20%,Z形、回转运动参数预报偏差小于6%。

关键词：水动力系数参数辨识贝叶斯岭回归模型操纵运动模型

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Online Magnetic Flux Leakage Detection System for Sucker Rod Defects Based on LabVIEW Programming

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Computers, Materials & Continua 2019年第2期58卷 529-544页

作者： ou Zhang Xueye wei School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing100044China

Aiming at the detection of the sucker rod defects,a real-time detection system is designed using the non-destructive testing technology of magnetic flux leakage(MFL).An MFL measurement system consists of many parts,and this study focuses on the signal acquisition and processing *** of all,this paper introduces the hardware part of the acquisition system in detail,including the selection of the Hall-effect sensor,the design of the signal conditioning circuit,and the working process of the single chip computer(SCM)control serial *** on LabVIEW,a graphical programming software,the software part of the acquisition system is written,including serial port parameter configuration,detection signal recognition,original signal filtering,real-time display,data storage and ***,an experimental platform for the MFL detection is set up,and the MFL measurement is carried out on the transverse and longitudinal defects of the sucker rod *** experimental result shows that the designed acquisition and processing system has good detection performance,simple design and high flexibility.

关键词： flux leakage testing real-time detection sucker rod LabVIEW acquisition and processing

肝脏巨噬细胞在慢性乙型肝炎病毒感染中的研究进展

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中华检验医学杂志 2025年第1期48卷 153-158页

作者：郭鸿燕傅亚欧启水福建医科大学附属第一医院检验科、福建省检验医学重点实验室、福建医科大学附属第一医院滨海院区国家区域医疗中心、福建医科大学基因诊断研究中心福州350005

肝脏巨噬细胞是肝脏固有免疫的关键成员,其在慢性乙型肝炎病毒(HBV)感染中发挥重要作用。受肝脏微环境影响,肝脏巨噬细胞可表现出不同的免疫表型和功能,具有抑制HBV感染和介导免疫耐受的双重作用。HBV也可主动调控肝脏巨噬细胞表型,从... 详细信息

肝脏巨噬细胞是肝脏固有免疫的关键成员,其在慢性乙型肝炎病毒(HBV)感染中发挥重要作用。受肝脏微环境影响,肝脏巨噬细胞可表现出不同的免疫表型和功能,具有抑制HBV感染和介导免疫耐受的双重作用。HBV也可主动调控肝脏巨噬细胞表型,从而有利于病毒持续感染。鉴于肝脏巨噬细胞和HBV间的相互作用直接影响HBV感染的结局,并且靶向巨噬细胞的标志物具有潜在的临床实践价值,因此,该文将从肝脏巨噬细胞的来源与异质性、肝脏巨噬细胞与HBV之间的相互作用,以及巨噬细胞相关的HBV感染潜在免疫学血清标志物三个方面,阐述肝脏巨噬细胞在HBV感染中的研究进展。

关键词：乙型肝炎病毒肝巨噬细胞免疫微环境免疫学血清标志物

Metallic ureteral stent in restoring kidney function: Nine case reports

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World Journal of Clinical Cases 2020年第13期8卷 2841-2848页

作者： wei Gao Tong-wen ou Xin Cui Jiang-Tao Wu Bo Cui Department of Urology Xuanwu HospitalCapital Medical UniversityBeijing 100053China

BACKGRouND Retroperitoneal fibrosis is an exceptionally rare disease characterized by proliferation of fibrous tissue and inflammation in the *** features many symptoms in the kidneys and in other organs and usually leads to ureteral *** SUMMARY Here we present 9 consecutive cases of idiopathic retroperitoneal fibrosis(IRPF)in patients who presented to the Department of Nephrology or Department of Rheumatology,Xuanwu Hospital,Capital Medical University,Beijing,China,between January 2012 and June 2017 with ureteral obstruction due to external compression of the ureter that led to hydronephrosis and kidney *** tomography imaging was used to identify hydronephrosis and ureteral obstruction and to evaluate kidney *** patient was diagnosed with IRPF based on clinical observation and computed tomography examination *** restore kidney function,a retrograde metallic stent was placed in the ureter under X-ray guidance 2 d after each patient’s *** perioperative complications occurred in any patient,but postoperative complications occurred in two patients as follows:Patient 2 had stent migration and repeated metallic stent infections that resolved with treatment;and patient 4 had postoperative hematuria because he resumed normal activities too soon after stent placement(contrary to instruction).Placement of the metallic ureteral stents provided relief from ureteral obstruction and restored kidney function in all *** our 9-case series underscores the utility and efficacy of applying the Resonance®metallic ureteral stent to treat ureteral obstruction in patients with *** all retroperitoneal fibrosis cases in our series,ureteral stents provided effective relief and were shown to reduce the incidence rate of perioperative and postoperative complications.

关键词： Retroperitoneal fibrosis Metallic ureteral stent Ureteral obstruction Computed tomography Kidney function Plastic stent Case report

In-Plane Impact Dynamics Analysis of Re-Entrant Honeycomb with Variable Cross-Section

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Computer Modeling in Engineering & Sciences 2021年第4期127卷 209-222页

作者： Yuanxun ou Shilin Yan Pin wen Department of Engineering Structure and Mechanics Wuhan University of TechnologyWuhan430070China Hubei Key Laboratory of Theory and Application of Advanced Materials Mechanics Wuhan430070China

Due to the unique deformation characteristics of auxetic materials(Poisson’s ratioμ<0),they have better shock resistance and energy absorption properties than traditional *** by the concept of variable crosssection ... 详细信息

Due to the unique deformation characteristics of auxetic materials(Poisson’s ratioμoung’s modulus,plateau stress,and specific energy absorption(SEA)than traditional re-entrant honeycomb(RH).The influence of microstructure parameters(such as cross-section change rateα)on the dynamic impact performance of VCRH is also *** show that,with the increase in impact velocity andα,the plateau stress and SEA of VCRH increase.A positive correlation is also found between the energy absorption efficiency,impact load uniformity andαunder both medium and high impact *** results can provide a reference for designing improved auxetic re-entrant honeycomb structures.

关键词： Auxetic re-entrant honeycombs variable cross-section design in-plane impact finite element simulation

Semivolatile organic compounds, organochlorine pesticides and heavy metals in sediments and risk assessment in Huaihe River of China

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Journal of Environmental Sciences 2006年第2期18卷 236-241页

作者： HUANG Hong ou wen-hua WANG Lian-sheng College of Marine Science and Technology Shanghai Fisheries University Shanghai 200090 China School of Environmental Science and Technology Tongji University Shanghai 200092 China College of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China State Key Laboratory of Pollution Control and Resources Reuse School of the Environment Nanjing University Nanjing 210093 China

The concentrations of semivolatile organic compounds, organochlorine pesticides and heavy metals in sediments from Jiangsu reach of Huaihe River, China, were presented. The organic compounds were extracted by acetone： n-hexane using a Soxhlet apparatus and concentrations were performed using HP6890 gas chromatography coupled by FID and ECD detector. The total contents of 8 heavy metals by inductively coupled plasma atomic emission spectrometry or cold-vapor/atomic absorption spectrometry were developed. 30 semivolatile organic compounds were detected, including substituted benzenes, phenols, phthalates and polycyclic aromatic hydrocarbons, from 0.01 to 3.01 mg/kg. 16 organochlorine pesticides were almost detected and from 0.010 to 2.339 μg/kg. Concentrations of major metals were 50 mg/kg or less, mean level of mercury was only 0.055 mg/kg. Compared to sediment quality guidelines （SQGs）, concentrations of some semivolatilc organic compounds were high enough to cause possible toxic effects to living resources. The organochlorine pesticides presented relatively low, lower than threshold effect concentrations （TECs）, harmful effects on sediment-dwelling organisms were not expected. Chromium posed probable toxic effects to the living resources, other heavy metals had no threat temporarily according to SQGs.

关键词： sediment semivolatile organic compounds organochlorinc pcsticidcs heavy mctals sediment quality guiedlines Huaihe River

Effects of octreotide on glucose transporter type 2expression in obese rat small intestine

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World Journal of Gastroenterology 2011年第39期17卷 4434-4439页

作者： Na wei Rui Liu Yan ou Xian Li ou Qiang wei Guo Cheng-wei Tang Division of Peptides Related to Human Disease National Key Laboratory of Biotherapy West China Hospital Sichuan University Chengdu 610041 Sichuan Province China Department of Gastroenterology West China Hospital Sichuan University Chengdu 610041 Sichuan Province China

AIM： TO investigate the effects of the somatostatin analogue, octreotide, on maltose and sucrase activities and expression of glucose transporter type 2 （GLUT2） in obese rat intestinal mucosa. METHODS： We divided 49 Sprague-Dawley rats into a group of 31 high fat diet-induced obese rats and a group of 18 normal controls. The obese rats were separated into an octreotide treated group 9f 16 rats and an obese group of 15. The intervention （：jroup was injected with octreotide at 40 ±g/kg body weight every 12 h for 8 d. Rat body weight was measured weekly to calculate Lee＇s index. After euthanization, maltase and sucrase activities in the small intestine were measured by activity assays, and the fasting plasma glucose level was measured. The expression of GLUT2 in small intestinal mucosa was analyzed by immunohistochemistry, reverse transcriptase polymerase chain reaction and Western blotting assays. RESULTS： Body weight, Lee＇s index, fasting plasma glucose level, maltase activity in small intestinal mucosa, mucosa and apical GLUT2, GLUT2 mRNA and protein expression levels were all significantly higher in the obese group than in the normal control group （605.61 ± 141.00 vs 378.54 ±111.75, 337.61 ± 10.82 vs 318.73 ± 20.10, 8.60± 1.38 vs 7.33 ± 0.70, 156.01 ± 58.81 vs 50.43 ± 30.49, 390 744.2± 62 469.21 vs 170 546.50 ± 50 646.14, 26 740.18 ±3809.60 vs 354.98± 57.19, 0.26± 0.11 vs 0.07± 0.02, and 2.08 ± 0.59 vs 1.27 ± 0.38, respectively, all P 〈 0.01）. Sucrase activity did not differ between the two groups. Octreotide intervention significantly decreased the body weight and fasting plasma glucose level of obese rats （508.27 ± 94.39 vs 605.61 ± 141.00, 7.58 ± 1.51 vs 8.60±1.38, respectively, all P 〈 0.05）. The intestinal mucosa and apical GLUT2, expression of GLUT2 mRNA and protein were also significantly lower in the octreotide intervention group than in the obese group （269 975.2 ± 53 730.94 vs 390 744.2 ± 62 469.21, 3758.06 ± 364.51 vs 26 740.18 ± 3809.60, 0.08 ± 0.02 vs

关键词： Glucose transporter type 2, High fat diet Maltase Obesity Octreotide Rat Small intestinal absorption