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Vertical Distribution Characteristics of PM2.5 Observed by a Mobile Vehicle Lidar in Tianjin, China in 2016

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Journal of Meteorological Research 2018年第1期32卷 60-68页

作者： Lihui LYU Yunsheng DONG Tianshu zhang Cheng LIU Wenqing LIU Zhouqing XIE Yan XIANG Yi zhang Zhenyi CHEN Guangqiang FAN leibo zhang Yang LIU Yuchen SHI Xiaowen SHU Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences Hefei 230031 University of Science and Technology of China Hefei 230026 Tianjin Academy of Environmental Sciences Tianjin 300191 Chinese Academy of Sciences Wuxi Photonics Co. Ltd. Wuxi 214135 The AirForce Military Representative's Office in Beijing Beijing 100086

We present mobile vehicle lidar observations in Tianjin, China during the spring, summer, and winter of 2016. Mobile observations were carried out along the city border road of Tianjin to obtain the vertical distribution characteristics of PM2.5. Hygroscopic growth was not considered since relative humidity was less than 60% during the observation experiments. PM2.5 profile was obtained with the linear regression equation between the particle extinction coefficient and PM2.5 mass concentration. In spring, the vertical distribution of PM2.5 exhibited a hierarchical structure. In addition to a layer of particles that gathered near the ground, a portion of particles floated at 0.6–2.5-km height. In summer and winter, the fine particles basically gathered below 1 km near the ground. In spring and summer, the concentration of fine particles in the south was higher than that in the north because of the influence of south wind. In winter, the distribution of fine particles was opposite to that measured during spring and summer. High concentrations of PM2.5 were observed in the rural areas of North Tianjin with a maximum of 350 μg m^–3 on 13 December2016. It is shown that industrial and ship emissions in spring and summer and coal combustion in winter were the major sources of fine particles that polluted Tianjin. The results provide insights into the mechanisms of haze formation and the effects of meteorological conditions during haze–fog pollution episodes in the Tianjin area.

关键词： mobile vehicle lidar vertical concentration profile fine particle

Olfactory and gustatory dysfunctions of COVID-19 patients in China:A multicenter study

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2022年第4期8卷 297-301页

作者： Jianhui Li Yi Sun Enqiang Qin Hu Yuan Mingbo Liu Wenqi Yi Zhu Chen Chengcheng Huang Fengjie Zhou Ruiyao Chen leibo zhang Ning Yu Qiong Liu Xuejun Zhou Jingjing He Boyu Li Fusheng Wang Changliang Yang Shiming Yang College of Otolaryngology Head and Neck Surgery Chinese PLA General HospitalBeijingChina National Clinical Research Center for Otolaryngologic Diseases BeijingChina Department of Otolaryngology Head and Neck Surgery Chinese PLA General Hospital Hainan HospitalSanyaChina Hainan Clinical Research Center for Otolaryngologic Diseases SanyaChina Department of Otolaryngology Head and Neck Surgery General Hospital of Central Theater CommandWuhanChina Treatment and Research Center for Infectious Diseases The Fifth Medical Center of Chinese PLA General HospitalBeijingChina National Clinical Research Center for Infectious Diseases BeijingChina

Introduction:With the spread of the epidemic worldwide,an increasing number of doctors abroad have observed the following atypical symptoms of coronavirus disease 2019(COVID-19):olfactory or taste ***,clarifying the incidence and clinical characteristics of olfactory and taste disorders in Chinese COVID-19 patients is of great significance and *** and Methods:A retrospective study was conducted,which included 229 severe acute respiratory syndrome coronavirus 2 confirmed patients,through face-to-face interviews and telephone *** the completion of questionnaires,the patients participating in the study,were categorized according to the degree of olfactory and taste disorders experienced,and the proportion of each clinical type of patient with olfactory and taste disorders and the time when symptoms appeared were ***:Among the 229 patients,31(13.54%)had olfactory dysfunction,and 44(19.21%)had gustatory *** the patients with olfactory dysfunction,6(19.35%)developed severe disease and became critically *** dysfunction appeared before the other symptoms in 21.43%of *** proportion of females with olfactory and gustatory dysfunction was higher than that of males(P<0.001).Conclusions:The incidence of olfactory and gustatory dysfunction was much lower than that reported abroad;the prognosis of patients with olfactory dysfunction is relatively favorable;olfactory and gustatory dysfunction can be used as a sign for early screening;females are more prone to olfactory and gustatory dysfunction.

关键词： COVID-19 gustatory olfactory SARS-CoV-2

Overview of the Mars climate station for Tianwen-1 mission

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Earth and Planetary Physics 2020年第4期4卷 371-383页

作者： YongQing Peng leibo zhang ZhiGuo Cai ZhaoGang Wang HaiLong Jiao DongLi Wang XianTao Yang LianGuo Wang Xu Tan Feng Wang Jing Fang ZhouLu Sun HongLiang Feng XiaoRui Huang Yan Zhu Ming Chen LiangHai Li YanHua Li Beijing Research Institute of Telemetry Beijing 100076China National Space Science Center Chinese Academy of SciencesBeijing 100012China National Astronomical Observatories Chinese Academy of SciencesBeijing 100012China Chinese Academy of Aerospace Electronics Technology Beijing 100012China

The background and scientific objectives of the Mars Climate Station(MCS)for Tianwen-1 are introduced,accompanied by a comparative review of the status of related meteorological observation missions and of advanced sensing *** one of the China Tianwen-1 Mission’s principal scientific payloads,the MCS contains four measurement sensors and one electronic processing unit that are specially designed to measure local temperature,pressure,wind,and sound on the Martian *** MCS’s measurement principles,technical schemes,ground calibration techniques,and adaptability evaluation to the Mars surface environment of MCS are introduced in *** conclusion presents measurement performance specifications of the MCS,based on ground test results,that will provide guidance to future research based on data from the Tianwen-1 and later Mars missions.

关键词： Tianwen-1 Mars exploration Mars climate station

熔制保温时间对CAMS系矿渣微晶玻璃结构与性能的影响

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材料导报 2017年第18期31卷 125-130页

作者：邓磊波张雪峰张明星欧阳顺利殷哲一内蒙古科技大学内蒙古自治区白云鄂博矿多金属资源综合利用重点实验室包头014010 内蒙古科技大学理学院包头014010

以白云鄂博二次选后尾矿、高炉渣和粉煤灰为主要原料,采用熔融法制得CaO-Al_2O_3-MgO-SiO_2(CAMS)系微晶玻璃,利用DSC、XRD、SEM、EDS、Raman、红外光谱及理化性能测试手段,研究了熔制过程中不同保温时间对微晶玻璃结构与性能的影响。... 详细信息

以白云鄂博二次选后尾矿、高炉渣和粉煤灰为主要原料,采用熔融法制得CaO-Al_2O_3-MgO-SiO_2(CAMS)系微晶玻璃,利用DSC、XRD、SEM、EDS、Raman、红外光谱及理化性能测试手段,研究了熔制过程中不同保温时间对微晶玻璃结构与性能的影响。结果表明:随着熔制保温时间的延长,矿渣玻璃熔液中氟的挥发及对氧化铝坩埚的侵蚀导致基础玻璃中氟含量降低而Al2O3含量升高,基础玻璃析晶温度呈先上升后下降的趋势,微晶玻璃主晶相为透辉石,晶粒出现先细化后粗化的趋势,第二相萤石相随着保温时间的延长逐渐消失,最终导致微晶玻璃结构及理化性能发生改变。当玻璃熔制保温时间为5h时,制备的微晶玻璃综合性能最优,其密度、抗折强度、显微硬度及耐酸碱性分别为3.09g/cm3、201 MPa、7 021 MPa、97.78%和98.83%。

关键词：熔制保温时间矿渣微晶玻璃白云鄂博尾矿氧化铝坩埚

水射流空化对NiTi形状记忆合金显微组织和超弹性的影响

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排灌机械工程学报 2024年第3期42卷 319-324页

作者：王雷博陈杰刘海霞欧阳亚东邹杨张永超江苏大学材料科学与工程学院江苏镇江212013 江苏大学能源与动力工程学院江苏镇江212013

为了探究水射流空化对NiTi形状记忆合金的显微组织和性能的影响机制,采用水射流空化发生装置在自来水介质中对NiTi形状记忆合金进行不同时间的射流空化试验,并借助SEM,XRD,TEM、显微维氏硬度计、纳米压痕仪、激光共聚焦显微镜对样品的... 详细信息

为了探究水射流空化对NiTi形状记忆合金的显微组织和性能的影响机制,采用水射流空化发生装置在自来水介质中对NiTi形状记忆合金进行不同时间的射流空化试验,并借助SEM,XRD,TEM、显微维氏硬度计、纳米压痕仪、激光共聚焦显微镜对样品的显微组织、物相和性能进行表征.结果表明:在射流空化20 min内,NiTi形状记忆合金表面显微硬度和超弹性均随射流时间的延长而增加;当射流时间为15 min时,NiTi形状记忆合金中出现大量位错,表面显微硬度HV达到最大值340.35(载荷约为0.245 N),与原样相比提高约34%;水射流空化对NiTi合金的影响层深度约为300μm;以纳米压痕能量恢复率来衡量合金的超弹性,在水射流空化15 min内,合金的弹性能量恢复率从38.25%提升至45.70%,表明水射流空化处理可有效提升试样的超弹性;NiTi形状记忆合金中显微硬度和超弹性的提升可归因于合金中的位错增殖.

关键词：射流空化显微组织表面形貌显微硬度超弹性

同方期刊数据库

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生态友好型抑尘剂的制备及性能

农业工程学报 2013年第18期29卷 218-225页

作者：张雷波焦姣赵雪艳张静邹德坤姬亚芹单春艳南开大学环境科学与工程学院天津300071 中国环境科学研究院北京100012

为控制中国北方裸露农田土壤风蚀,改善城市环境质量,该文以盐地碱蓬籽饼为主要原料,以十二烷基苯磺酸钠、羧甲基纤维素钠、聚乙烯醇等为辅料,经生物改性,制备了一种生态友好型抑尘剂并研究了其保湿性、水稳定性、抗风蚀性等性能以及该... 详细信息

为控制中国北方裸露农田土壤风蚀,改善城市环境质量,该文以盐地碱蓬籽饼为主要原料,以十二烷基苯磺酸钠、羧甲基纤维素钠、聚乙烯醇等为辅料,经生物改性,制备了一种生态友好型抑尘剂并研究了其保湿性、水稳定性、抗风蚀性等性能以及该抑尘剂对种子出苗率及农田土壤土质的影响。结果表明,该抑尘剂喷洒后易形成团粒结构,可起到保护表层土壤的作用;在25℃时,黏度可高达到55.1 mPa·s,常温下使用时具有较好的黏结性能;保湿时间可以延长至72 h以上,具有良好的保湿性;能够抗击4次雨水冲蚀,具有较好的水稳性;单位面积土壤颗粒累积损失量小于0.7 g/m^2,抑尘效率提高了99%以上;可增加土壤中植物生长所需的一些营养成分,可提高作物出苗率,促进作物生长;每平方米的使用成本约为0.5元。该文可为今后抑尘剂研究与实践提供参考。

关键词：土壤侵蚀环境保护生态友好抑尘剂碱蓬籽饼

应用地质累积指数评价抚顺市PM_(10)中元素的污染

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环境污染与防治 2012年第6期34卷 66-70页

作者：焦姣张雷波姬亚芹南开大学环境科学与工程学院天津300071

2006-2007年采暖季、风沙季和非采暖季分别在抚顺市的6个采样点采集PM10样品,用等离子体原子发射光谱(ICP-AES)法测定样品中Ti、Al、Mn、Mg、Ca、Na、K、Cu、Zn、As、Pb、Cr、Ni、Co、Cd、Fe、V等17种元素的含量,并用地质累积指数对其... 详细信息

2006-2007年采暖季、风沙季和非采暖季分别在抚顺市的6个采样点采集PM10样品,用等离子体原子发射光谱(ICP-AES)法测定样品中Ti、Al、Mn、Mg、Ca、Na、K、Cu、Zn、As、Pb、Cr、Ni、Co、Cd、Fe、V等17种元素的含量,并用地质累积指数对其污染状况进行初步评价。结果表明:(1)从PM10中元素在不同采样点的含量看,抚顺市PM10中Ti、Mn、Mg、Cu、Zn、Pb、Cr、Ni、Co这9种元素在各采样点间的差别较大;Al、Ca、Na、K、As、Cd、Fe、V这8种元素差别较小。(2)从PM10中元素在不同采样季的含量看,抚顺市PM10中Mn、Mg含量的季间差别较大,其余15种元素季间差别较小。(3)Zn、Cd污染较重;Ti、Al、Mg、Ca、Na、K、As、Fe和V污染较轻;其他6种元素在6个采样点和3个采样季污染程度差别较大。(4)水库采样点各元素污染级别均不是最高;新华采样点PM10中Cu、Zn、Pb、Cr、Ni、Co、Cd污染级别均较高。(5)3个采样季PM10中Cd、Zn污染均较重,属于重度或严重污染;在采暖季PM10中Cu、Pb、Cr的地质累积指数较风沙季、非采暖季大;在非采暖季PM10中Mn、Co受到的污染比采暖季和风沙季稍严重。

关键词： PM10 地质累积指数抚顺市

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小肠间质瘤20例临床分析

陕西医学杂志 2008年第4期37卷 446-447页

作者：兰乃祥张雷波谭栋陕西省核工业二一五医院咸阳712000

目的:总结小肠间质瘤诊断和治疗经验。方法:对20例小肠间质瘤患者的临床资料进行回顾性分析。结果:临床表现为腹部疼痛11例,血便14例,伴贫血8例;发病时间2d至5年。确诊方式:血管造影检查8例,剖腹探查4例,腹部核素扫描(ECT)确诊小肠出血1... 详细信息

目的:总结小肠间质瘤诊断和治疗经验。方法:对20例小肠间质瘤患者的临床资料进行回顾性分析。结果:临床表现为腹部疼痛11例,血便14例,伴贫血8例;发病时间2d至5年。确诊方式:血管造影检查8例,剖腹探查4例,腹部核素扫描(ECT)确诊小肠出血1例,术前CT、B超、MRI检查发现腹部包块3例,其他手术中无意发现4例,但均未能明确病因。手术方式:小肠间质瘤切除18例,胰十二指肠切除术1例,肿瘤无法切除行保守治疗1例。随访6个月至9年,除1例死于心脏病,1例长期服用甲磺酸伊马替尼(Gleevec)症状缓解外,其余18例均存活,间质瘤无复发。结论:小肠间质瘤预后较好,但对不明原因的腹痛、消化道出血应及早行血管造影或手术探查,以避免误诊;Gleevec对晚期小肠间质瘤有较好疗效。

关键词：胃肠肿瘤/诊断胃肠肿瘤/治疗小肠

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高校教育信息化发展存在的问题与对策研究

中国医学教育技术 2007年第6期21卷 463-466页

作者：梁军张凤张雷勃西安交通大学医学院第一附属医院陕西西安710061

高校教育信息化是当今教育改革的热门话题。通过对高校教育信息化概念、现状等的介绍，较全面地分析了高校教育信息化在发展过程中出现的、以及高校教育信息化本身存在的问题，并且针对这些问题提出相应的对策，以期推进高校教育信息化... 详细信息

高校教育信息化是当今教育改革的热门话题。通过对高校教育信息化概念、现状等的介绍，较全面地分析了高校教育信息化在发展过程中出现的、以及高校教育信息化本身存在的问题，并且针对这些问题提出相应的对策，以期推进高校教育信息化更好地发展。

关键词：高校教育信息化问题对策