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Distribution of eight heavy metals in the inner shelf sediments of East China Sea:Risk assessments and sources analysis

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Ecosystem Health and Sustainability 2021年第1期7卷 87-101页

作者： Chunjie Wang zhangwei Wang xiaoshan zhang State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijingChina College of Resources and Environment University of Chinese Academy of SciencesBeijingChina

Although numerous studies on heavy metals(HMs)in sediments have been carried out in the East China Sea(ECS),the knowledge on the recent pollution levels of HMs in coastal region remains not well understood due to the rapid developments of urbanization in eastern *** this study,23 surface samples and 4 core samples are collected in the inner shelf of the *** average dry-weight concentrations follow the descending order of Zn,Cr,Ni,Pb,Cu,As,Cd,and Hg(103.6±26.0,42.8±12.4,37.0±9.1,34.7±11.1,19.5±10.3,15.7±11.6,0.056±0.017,and 0.041±0.017μg g^(−1),respectively).HMs concentrations share a similar spatial distribution pattern of TOC content with a decreasing trend from coastline to outer ***,HMs concentrations exhibit a decreasing trend from top to bottom sediments,especially for Hg at the open sites due to the wet and dry deposition of atmospheric Hg besides the riverine *** potential ecological risk indices(PERI)values in coastal sediments were about 2-4 times higher than those in open *** the Hg and Cd concentrations were lower by 2-3 orders of magnitude than those of other six metals,the PERI values of Hg(65.5)and Cd(52.1)were 3-40 times higher than those of *** hierarchical cluster result is consistent with the PCA result,suggesting that Hg,Cd,and As have similar sources and probably mainly originated from anthropogenic emissions.

关键词： Heavy metals spatial distribution cores environmental risk east China Sea

多模态影像评估主动脉瓣置换术后左心室逆重构研究进展

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中国医学影像学杂志 2024年第10期32卷 1080-1084页

作者：金之湲王雅晳段莎莎施依璐付文艳张丹陈启张小杉内蒙古医科大学附属医院超声科内蒙古呼和浩特010050

慢性主动脉瓣狭窄及反流可导致左心室重构,这些变化在瓣膜置换术后是否可逆及可逆程度是影响外科手术时机和患者预后的主要决定因素。影像技术是目前常用于评估心肌结构与功能的无创性方法,其中超声心动图及增强CT有助于人工瓣功能评估... 详细信息

慢性主动脉瓣狭窄及反流可导致左心室重构,这些变化在瓣膜置换术后是否可逆及可逆程度是影响外科手术时机和患者预后的主要决定因素。影像技术是目前常用于评估心肌结构与功能的无创性方法,其中超声心动图及增强CT有助于人工瓣功能评估和左心室形变监测,心脏磁共振及PET/CT有助于识别术后心纤维化的进展及消退,这些技术综合应用可早期诊断和无创检测术后左心室逆重构,从而改善临床结局。本文综述多模态影像学技术对主动脉瓣置换术后左心室逆重构评估及应用进展。

关键词：心室心脏瓣膜假体植入多模态成像逆重构超声心动描记术磁共振成像心肌灌注显像 CT血管造影术综述

Dissolved organic sulfur in streams draining forested catchments in southern China

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Journal of Environmental Sciences 2012年第4期24卷 704-710页

作者： Zhanyi Wang xiaoshan zhang zhangwei Wang Yi zhang Bingwen Li Rolf Vogt Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China College of Ecology and Environmental Science Inner Mongolia Agricultural UniversityHohhot 010018China Department of Chemistry University of OsloP.O.BOX 1033BlindernN-0315 OsloNorway

Dissolved organic sulfur （DOS） is an important fraction for sulfur mobilization in ecosystem. In this work stream waters were sampled in 25 forested sites in southern China to study the dissolved sulfur fractions. Dissolved sulfur was fractionated into dissolved organic sulfur （DOS） and inorganic sulfate （SO]-） for 95 stream water samples. The results showed that the concentration of DOS ranged from 0 to 13.1 mg/L （average 1,3 mg/L） in all the streams, High concentrations of DOS in stream waters were found in the sites with high concentrations of sulfate. DOS constituted less than 60.1% of dissolved sulfur （average 17.9%）. Statistical analysis showed that DOS concentration was correlated with SO42- in streams waters and total sulfur in surface layer soils. The results also showed that DOS concentration in stream waters had a seasonal variation, but no trends were found with it. The implication was that the long term sulfur deposition had led the increase of the concentration and fraction of DOS in stream waters in acid rain prevailing regions

关键词： dissolved organic sulfur stream water Chinese forests sulfur deposition

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超声造影诊断下肢淋巴水肿的研究进展

中国医学影像学杂志 2024年第1期32卷 109-112页

作者：付文艳王雅晳段莎莎施依璐金之湲张小杉内蒙古医科大学附属医院超声医学科内蒙古呼和浩特010050

下肢淋巴水肿是一种慢性、进行性疾病,严重影响患者生活质量;早期诊断和治疗可延缓病情进展,有利于改善患者预后。目前常见的下肢淋巴水肿诊断技术均具有一定的缺点而使应用受限。超声造影具有无创、便捷、实时、重复性好的特点,能够增... 详细信息

下肢淋巴水肿是一种慢性、进行性疾病,严重影响患者生活质量;早期诊断和治疗可延缓病情进展,有利于改善患者预后。目前常见的下肢淋巴水肿诊断技术均具有一定的缺点而使应用受限。超声造影具有无创、便捷、实时、重复性好的特点,能够增强淋巴管中淋巴液的显像,对浅表淋巴管显像具有较高敏感度,近年来逐渐应用于下肢淋巴水肿诊断。本文对超声造影在下肢淋巴水肿中的应用情况进行综述。

关键词：下肢淋巴水肿超声造影彩色多普勒超声综述

Optimization of Co-precipitation Condition for Preparing Molybdenum-Based Sulfur-Resistant Methanation Catalysts

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Transactions of Tianjin University 2019年第5期25卷 504-516页

作者： Jiahui zhang xiaoshan zhang Baowei Wang Zhenhua Li Xinbin Ma Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) Tianjin UniversityTianjin 300072China

In this study, the e ects of ZrO 2 carrier precursors, MoO 3 loading, and washing treatment on the catalytic performance of M o O 3 /ZrO 2 toward sulfur-resistant methanation were investigated. All the catalysts were prepared by co-precipitation method and further characterized by N 2 adsorption desorption, H 2 -temperature-programmed reduction, X-ray di raction, Raman spectroscopy and transmission electron microscopy. The prepared MoO 3 /ZrO 2 catalysts were tested in a continuous- ow pressurized xed bed reactor for CO methanation. The results revealed that the carrier precursors, MoO3 loading, and wash- ing treatment a ected not only the crystalline phase of Mo species but also the grain size of ZrO 2 carrier and consequently in uenced the MoO 3 /ZrO 2 activity toward sulfur-resistant methanation. The 25 wt% M oO 3 /ZrO 2 catalyst prepared using Zr(NO 3 ) 4 5H 2 O as the precursor and treated by water washing displayed the best activity for sulfur-resistant methanation due to its greater number of octahedral Mo species and smaller ZrO 2 grain size.

关键词： Sulfur-resistant methanation Co-precipitation Molybdenum ZrO 2

The soil displacement measurement of mercury emission flux of the sewage irrigation farmlands in Northern China

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Ecosystem Health and Sustainability 2019年第1期5卷 169-180,I0021页

作者： Yu Gao zhangwei Wang Chunjie Wang xiaoshan zhang Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijingChina College of Resources and Environment University of Chinese Academy of SciencesBeijingChina

Mercury fate of sewage irrigation in farmlands deserves attention with increasing scarcity of freshwater resources for agriculture in the ***-air total gaseous mercury(TGM)fluxes from four-sewage and one-fresh water irrigated farmlands were determined *** maize-wheat rotation,soil-air TGM fluxes showed patterns of both emission and deposition during different growth *** enhanced one-order of magnitude emission with increased Hg contamination from historical sewage irrigation.A linear response relationship of TGM fluxes with soil Hg concentration was found,which showed greater TGM emission potential comparing with those from forest and urban ***,the ratio of soil-air TGM flux in daytime to nighttime were 3.94 in maize-season and 3.41 in wheat-season,respectively,which were little related to the change in soil Hg ***,soil temperature and moisture,ambient-air TGM concentration all effected TGM evasion from sewage-irrigated *** data presented here suggest that evasion of TGMfromhistorical sewage irrigation farmlands with high Hg concentrations may be potential hotspots for Hg emission in atmosphere,and it was likely to underestimate Hg emissions from farmlands in existing emissions *** regionalinvestigations and process-level researches are needed to better understand role of sewage irrigation farmlands in local-global Hg-biogeochemical-cycles.

关键词： Soil-air mercury exchange flux sewage irrigation farmland maize-wheat rotation soil displacement environmental factors

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环境空气中小分子有机酸的组成和浓度特征

环境科学学报 2024年第9期44卷 10-20页

作者：陈炳蓉霍美蓉高宇张逸郭敏杰田启秋赵泽花张晓山王章玮中国科学院生态环境研究中心城市与区域生态国家重点实验室北京100085 中国科学院大学北京100049 茅台学院资源环境系仁怀564507 茅台学院旅游管理系仁怀564507

有机酸是大气中含量丰富的有机化合物,对二次有机气溶胶的产生、云凝结核的形成和大气降水pH有重要影响.本研究利用GC-MS和离子色谱技术分析了典型城市北京市和典型酿酒工业集群区贵州省茅台镇环境空气小分子有机酸浓度和组成特征,并探... 详细信息

有机酸是大气中含量丰富的有机化合物,对二次有机气溶胶的产生、云凝结核的形成和大气降水pH有重要影响.本研究利用GC-MS和离子色谱技术分析了典型城市北京市和典型酿酒工业集群区贵州省茅台镇环境空气小分子有机酸浓度和组成特征,并探讨不同天气条件下有机酸浓度变化规律.结果表明:茅台镇大气中总有机酸平均浓度为(46.47±18.81)μg·m^(-3),北京为(22.98±14.27)μg·m^(-3),有机酸对茅台地区大气总酸的贡献较大.乙酸是两地环境空气中含量最为丰富的小分子有机酸,其中茅台镇乙酸浓度为(38.33±16.65)μg·m^(-3),北京市乙酸浓度为(11.77±8.45)μg·m^(-3).茅台镇环境空气中有机酸浓度通常在上午的10:00-13:00或下午16:00-19:00时达到最高点,而北京地区小分子有机酸浓度日变化峰值出现在16:00-19:00.在不同的天气条件下,北京的环境空气中有机酸的浓度会随着PM_(2.5)、NO_(2)和CO的浓度以及相对湿度的上升而增加.而在茅台地区,小分子有机酸的浓度会随着NO2浓度的增大而增大,随风速的增大则会减小.由于地形因素的差异,北京市有机酸主要受到区域气象因素和汽车尾气排放的双重影响,而茅台镇受本地排放源的影响更为显著.此外,通过对比中国典型城市北京、深圳和上海大气中的甲酸和乙酸浓度的历史变化,发现有机酸浓度正在升高,未来需深入探究大气中有机酸变化特征,强化有机酸生态环境风险防控.

关键词：有机酸空气北京茅台镇浓度特征

Synthesis and optical characterization of Eu^(2+),Tb^(3+)-codoped Sr_3Y(PO_4)_3 green phosphors

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Journal of Rare Earths 2018年第3期36卷 238-242页

作者： Anxiang Guan Zuizhi Lu Fangfang Gao xiaoshan zhang Huan Wang Tianjiao Huang Liya Zhou School of Chemistry and Chemical Engineering Guangxi University

A series of Eu^2＋,Tb^3＋-codoped Sr3 Y（PO4）3（SYP） green phosphors were synthesized by hightemperature solid-state reaction. Several techniques, such as X-ray diffraction, UV-vis spectrum,and photoluminescence spectrum, were used to investigate the obtained phosphors. The present study investigates in detail photoluminescence excitation and emission properties, energy transfer between the two dopants, and effects of doping ions on optical band gap. SYP：0.05 Eu2＋ phosphor shows an intense and broad excitation band ranging from 220 to 400 nm and exhibits a bright green emission band with CIE chromaticity coordinates（0.189, 0.359） under 350 nm excitation. Green emission of SYP：0.03 Tb3＋ is intensified by codoping with Eu^2＋, and energy transfer mechanism between them is demonstrated to be a dipole-dipole interaction. Upon 350 nm excitation, SYP：Eu^2＋,Tb^3＋ phosphors exhibits two dominating bands peaking at 466 and 545 nm, which are assigned to 4 f^65 d^1→4 f^7 transition of Eu^2＋ ions and ~5 D4→~7 F5 transition of Tb^3＋ ions, respectively. Optimal doping concentrations of Eu^2＋ and Tb^3＋ in the SYP host are 5 mol% and 15 mol%, respectively. Results indicate that SYP：Eu^2＋,Tb^3＋ phosphors are potentially used as green-emitting phosphors for white light-emitting diodes.

关键词： Luminescence Phosphors Optical properties Energy transfer Rare earths

Robust,fire-resistant,and thermal-stable SiZrNOC nanofiber membranes with amorphous microstructure for high-temperature thermal superinsulation

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Journal of Advanced Ceramics 2023年第1期12卷 36-48页

作者： xiaoshan zhang Nana XU Yonggang JIANG Haiyan LIU Hui XU Cheng HAN Bing WANG Yingde WANG Science and Technology on Advanced Ceramic Fiber and Composites Laboratory College of Aerospace Science and EngineeringNational University of Defense TechnologyChangsha 410073China

Ceramic nanofibers with robust mechanical properties,high-temperature resistance,and superior thermal insulation performance are promising thermal insulators used under extreme ***,developing of ceramic fibers with both low solid thermal conductivity(λs)and low infrared radiation thermal conductivity(λr)is still a great ***,according to the Ioffe-Regel limit theory,we report a novel SiZrNOC nanofiber membrane(NFM)with a typically amorphous structure by combining the electrospinning method and high-temperature pyrolysis technique in a NH3 *** prepared SiZrNOC NFM has a high tensile strength(1.98±0.09 MPa),excellent thermal stability(1100℃in air),and superior thermal insulation *** thermal conductivity of SiZrNOC NFM was 0.112 W·m^(−1)·K^(−1) at 1000℃,which is obviously lower than that of the traditional ceramic fiber membranes(>0.2 W·m^(−1)·K^(−1) at 1000℃).In addition,the prepared SiZrNOC NFM-reinforced SiO2 aerogel composites(SiZrNOCf/SiO2 ACs)exhibited ultralow thermal conductivity of 0.044 W·m^(−1)·K^(−1) at 1000℃,which was the lowest value for SiO2-based aerogel composites ever *** superior thermal insulation performance of SiZrNOC NFMs was mainly due to significant decreasing of solid heat conduction and thermal radiation by the fancy amorphous microstructure and high infrared shielding *** work not only provides a promising high-temperature thermal insulator,but also offers a novel route to develop other high-performance thermal insulating materials.

关键词： amorphous microstructure SiZrNOC nanofiber thermal stability thermal insulation