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Processing Nomex Nanofibers by Ionic Solution Blow‑Spinning for Efficient High‑Temperature Exhausts Treatment

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Advanced Fiber Materials 2023年第2期5卷 497-513页

作者： Zekun Cheng Haiyang Wang Ziwei Li Chong Yang baopu zhang Yiqian Zhou Yuxuan Wang Chao Jia Lei Li Hui Wu State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China National Engineering Research Center of Electric Vehicles Beijing Institute of TechnologyBeijing 100081China State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China

Hard-to-dissolve polymers provide next-generation alternatives for high-performance filter materials owing to their intrin-sically high chemical stability,superior mechanical performance,and excellent high-temperature ***,the mass production of hard-to-dissolve nanofibers still remains a critical challenge.A simple,scalable,and low-cost ionic solu-tion blow-spinning method has herein been provided for the large-scale preparation of hard-to-dissolve Nomex polymeric nanofibers with an average diameter of nearly 100 *** rapidly dissolving Nomex microfibers in the lithium chloride/dimethylacetamide(LiCl/DMAc)solution system,the conductive solution can be stably and conductivity-independently processed into *** method optimizes electrospinning and avoids spinnability degradation and potential safety hazards caused by high electrical *** to nanofibrous structure and high dipole moment,Nomex nanofibrous filters show a stable high filtration efficiency of 99.92%for PM_(0.3) with a low areal density of 4.6 g m^(-2),as well as a low-pressure drop of 189.47 ***,the flame-retardant filter can work at 250°C and 280°C for a long and short time without shrinking or burning,respectively,exhibiting a high filtration efficiency of 99.50%for PM_(0.3-10.0).The outstanding properties and low cost enable the efficient capture of PM from various high-temperature exhausts,making Nomex nanofi-brous membrane an even more ideal industrial-grade air filter than polypropylene,polytetrafluoroethylene,polyimide,and ceramic nanofibrous filters.

关键词： Nomex nanofibers Solution blow-spinning High-temperature filtration Flame-retardant

Bifunctional Activated Carbon Ultrathin Fibers:Combining the Removal of VOCs and PM in One Material

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Advanced Fiber Materials 2023年第6期5卷 1934-1948页

作者： Haiyang Wang Di Zu Xinyu Jiang Yong Xu Zhiwen Cui Peng Du Zekun Cheng Ziwei Li Lei Li Chong Yang Xiaopeng Bai baopu zhang Yiqian Zhou Kuangyu Wang Bohan Li Zhenghong Huang Lihao Zhao Bo Li Hui Wu State Key Lab of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084People’s Republic of China Institute of Materials Research Tsinghua Shenzhen International Graduate SchoolShenzhen 518055People’s Republic of China Applied Mechanics Laboratory Department of Engineering MechanicsTsinghua UniversityBeijing 100084People’s Republic of China Beijing Tongfang Envir-Clean Technology Co. LTDBeijing 100083People’s Republic of China

Volatile organic compounds(VOCs)and particulate matter(PM)are both frequently present in air as contaminants,posing serious health and environmental *** current filtration of VOCs utilizes entirely different materials compared with PM filtration,adding complexity to air cleaning ***,we design a pitch-based activated carbon ultrathin fibers(PACUFs)for bifunctional air *** PACUFs,with fiber diameter of∼1.2μm and specific surface area of 2341 m^(2) g^(−1),provide both high VOCs adsorption capacity(∼706 mg g^(−1))and excellent efficiency of∼97% PM_(0.3) filtration with low pressure *** contrast,traditional activated carbon fibers exhibit VOCs adsorption capacity of∼448 mg g^(−1) and PM_(0.3) removal efficiency of only∼36%at an equal area density of∼190 g m^(−2).Theoretical investigations reveal the filtration mechanism of the high-performance bifunctional fibrous PACUFs,considering full advantages of the high surface area,small pore size,and significant micropore volume.

关键词： Air pollutants Activated carbon fiber Melt-blown spinning Bifunctional purification

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贵州毕节麻窝口洞与智人伴生的长鼻类化石

人类学学报 2017年第3期36卷 414-425页

作者：王元赵凌霞杜抱朴张立召王新金蔡回阳中国科学院古脊椎动物与古人类研究所中国科学院脊椎动物演化与人类起源重点实验室北京100044 中国科学院大学北京100049 贵州省文物考古研究所贵阳520103 贵州省博物馆贵阳550001

最近在贵州毕节麻窝口洞发现了3枚古人类牙齿化石和伴生的哺乳动物群。其中,古人类牙齿经初步研究可归入解剖学上的现代人,而与古人类相伴的大、小哺乳动物化石,经初步鉴定共计8目20科43属53种。本文系统记述了该动物群中大哺乳动物的... 详细信息

最近在贵州毕节麻窝口洞发现了3枚古人类牙齿化石和伴生的哺乳动物群。其中,古人类牙齿经初步研究可归入解剖学上的现代人,而与古人类相伴的大、小哺乳动物化石,经初步鉴定共计8目20科43属53种。本文系统记述了该动物群中大哺乳动物的典型代表——长鼻类化石,共2属2种:东方剑齿象(Stegodon orientalis)和亚洲象(Elephas maximus)。麻窝口洞的长鼻类缺失我国南方早更新世的典型种类——中华乳齿象(Sinomastodon)和华南剑齿象(Stegodon huananensis),具有从典型的中更新世大熊猫-剑齿象动物群(Ailuropoda-Stegodon fauna)向晚更新世亚洲象动物群(Asian elephant fauna)过渡的特征。依动物群的性质和地貌地层的特征,毕节麻窝口洞的智人及伴生动物群的地质时代很可能为中更新世晚期或晚更新世早期,这与堆积物的光释光年代测定的初步结果(距今约11.2-17.8万年)基本吻合。麻窝口洞东方剑齿象与亚洲象的组合明显具有东洋界亚热带动物群的特点,指示温暖潮湿的气候,这些长鼻类与智人等生存于近水的森林和灌丛中,并镶嵌了一些草地。

关键词：长鼻类智人麻窝口洞贵州毕节更新世

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Food-Borne Poisoning Accident from Amanitin Toxin in Wild Mushrooms—Xingtai City,Hebei Province,China,2023

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China CDC weekly 2024年第3期6卷 56-59页

作者： baopu Lv Liang Liu Hao Xiao Qingbing Meng Rui zhang Yaqing An Yingli Jin Yu Ma Hengbo Gao Yongkai Li Qian He Yutao zhang Changqing Liu Xiaoyan Luo Xiaomin Xu Fenshuang Zheng Yingping Tian Hongshun zhang Dongqi Yao Emergency Department The Second Hospital of Hebei Medical UniversityShijiazhuang CityHebei ProvinceChina National Institute of Occupational Health and Poison Control Chinese Centre for Disease Control and PreventionBeijingChina Hebei Provincial Center for Disease Control and Prevention Shijiazhuang CityHebei ProvinceChina Zhejiang Provincial Center for Disease Control and Prevention Hangzhou CityZhejiang ProvinceChina Emergency Department The Affiliated Hospital of Yunnan UniversityKunming CityYunnan ProvinceChina

What is already known about this topic?Fatal poisonings caused by wild mushrooms containing amanita toxins pose a significant threat in the southern regions of *** toxins primarily induce gastrointestinal symptoms initially,which are then followed by potentially life-threatening acute liver *** is added by this report?This report contributes to the existing knowledge on these cases of poisoning by documenting the second occurrences in Hebei Province and the first occurrences in Xingtai *** individuals reported consuming wild mushrooms from the same origin,and laboratory tests confirmed the presence ofα-amanitin in their blood *** are the implications for public health practice?This underscores the risk associated with the collection and consumption of amanita toxin-containing mushrooms in *** is important to note that the identification of toxic and non-toxic mushrooms should not solely rely on personal experience or appearance.

关键词： Hebei consuming initially

Automatic Body Feature Extraction from Front and Side Images

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Journal of Software Engineering and Applications 2012年第12期5卷 94-100页

作者： Lingyan Jiang Jian Yao baopu Li Fei Fang Qi zhang Max Q.-H. Meng Department of Electronic Engineering The Chinese University of Hong Kong Hong Kong P.R. China School of Computer Electronics and Information Guangxi University Nanning Guangxi P.R. China School of Remote Sensing and Information Engineering Wuhan University Wuhan Hubei P.R. China Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences Shenzhen P.R. China

Human body feature extraction based on 2D images provides an efficient method for many applications, e.g. non-contact body size measurements, constructing 3D human model and recognizing human actions. In this paper a systematic approach is proposed to detect feature points of human body automatically from its front and side images. Firstly, an efficient approach for silhouette and contour detection is used to represent the contour curves of a human body shape with Freeman’s 8-connected chain codes. The contour curves are considered as a number of segments connected together. Then, a series of feature points on human body are extracted based on the specified rules by measuring the differences between the directions of the segments. In total, 101 feature points with clearly geometric properties (that rather accurately reflect the bump or turning of the contours) are extracted automatically, including 27 points corresponding to the definitions of the landmarks about garment measurements. Finally, the proposed approach was tested on ten human subjects and the entire 101 feature points with specific geography geometrical characteristics were correctly extracted, indicating an effective and robust performance.

关键词： Silhouette detection Contour representation Human feature point extraction

降水变化和叶龄对油蒿群落植物-土壤化学计量特征与生产力的调控

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生态学报 2024年第7期44卷 2898-2906页

作者：赖宝朴于明含王春媛张富崇张建玲北京林业大学水土保持学院北京100083 宁夏盐池毛乌素沙地生态系统国家定位观测研究站盐池751500

在掌握典型荒漠植物油蒿化学计量学特征沿随降水量变化的响应特征,并从叶片间的养分协调分配的角度阐明油蒿维持生产力的生物学机制,为气候变化背景下荒漠植被的演变预测提供依据。通过野外降水控制实验的方法,设置6个降水量梯度(减雨70... 详细信息

在掌握典型荒漠植物油蒿化学计量学特征沿随降水量变化的响应特征,并从叶片间的养分协调分配的角度阐明油蒿维持生产力的生物学机制,为气候变化背景下荒漠植被的演变预测提供依据。通过野外降水控制实验的方法,设置6个降水量梯度(减雨70%、减雨50%、减雨30%、自然降水、增雨30%和增雨50%),分别测定不同降水量下油蒿群落生产力及叶片、土壤的化学计量参数。结果表明:1)降水量增加的情况下,油蒿群落土壤TP含量由于淋溶作用而显著降低;降水量减少情况下,油蒿林地土壤SOC、TN、TP含量并未改变。油蒿叶片的SOC、TN含量在降水增加时无显著变化、降水减少时含量增加,降水过多或过少都会降低叶片TP含量。2)不同成熟度的叶片养分元素含量对降水变化具有差异响应。成熟叶片养分含量容易受到环境的影响,幼叶养分元素含量较为稳定,在降水减少的情况下,油蒿优先将C、P分配给了幼叶,选择牺牲成熟叶以维持幼叶的生长。3)油蒿的生产力随降水量的增加而升高,油蒿ANPP在增雨30%处理组达到最大值,但在增雨50%时ANPP降低,这与过量的降水引发土壤养分流失有关。ANPP与幼叶TP含量相关性极显著,与成熟叶各元素含量相关性均不显著,由此可以推测,在降水变化的情境下,油蒿存在养分内在生物学调节机制以实现植株最优生产效率。

关键词：化学计量特征降水量土壤养分叶片成熟度地上净初级生产力

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聚四氟乙烯覆膜滤料的高温热压覆膜工艺

东华大学学报（自然科学版） 2017年第5期43卷 645-650,688页

作者：林茂泉吴海波张旭东殷保璞东华大学纺织学院上海201620 江苏东方滤袋股份有限公司江苏阜宁224400

通过探究聚四氟乙烯覆膜滤料高温热压覆膜工艺,重点分析不同热压时间、压力和温度对覆膜滤料过滤性能的影响,通过单因素分析方法对不同参数的作用效果进行分析.结果表明:随着热压压力增大,滤料的孔径和透气率逐渐下降,而滤料的覆膜牢度... 详细信息

通过探究聚四氟乙烯覆膜滤料高温热压覆膜工艺,重点分析不同热压时间、压力和温度对覆膜滤料过滤性能的影响,通过单因素分析方法对不同参数的作用效果进行分析.结果表明:随着热压压力增大,滤料的孔径和透气率逐渐下降,而滤料的覆膜牢度持续增加;随着热压温度或热压时间的增加,滤料的孔径和透气率呈现先上升后下降的趋势,而覆膜牢度总体呈现增长趋势.此外,滤料的滤阻、过滤效率的变化规律与孔径的变化规律一致,采用适宜工艺方案制得的高温热压覆膜滤料的过滤效率均达到99%以上.

关键词：聚四氟乙烯薄膜高温热压工艺耐高温孔径

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JF205系列新型水轮机模型的开发研究

水利水电技术 1999年第11期30卷 58-61页

作者：彭忠年陈锐蒋学运徐抱朴张建光孟晓超中国水利水电科学研究院北京市100038

JF205系列混流式水轮机模型是中国水利水电科学研究院水力机电研究所新近开发的，适用于150～200m水头段．在试验中，首先对蜗壳、固定导叶与活动导叶、尾水管、转轮等通流部件进行了设计与加工．试验内容有效率试验、空化试验、水压脉... 详细信息

JF205系列混流式水轮机模型是中国水利水电科学研究院水力机电研究所新近开发的，适用于150～200m水头段．在试验中，首先对蜗壳、固定导叶与活动导叶、尾水管、转轮等通流部件进行了设计与加工．试验内容有效率试验、空化试验、水压脉动试验、飞逸试验等．通过将试验成果与我国中小型混流式水轮机转轮系列型谱中的相应转轮进行比较可看出，JF205系列水轮机模型具有高效区范围宽、空化性能好、最大单位飞逸转速低等优点，部分转轮的模型最优效率在国内首次突破94％大关．

关键词：混流式水轮机水力设计模型试验

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中国现代人群两性身高差异分布及其影响因素

人类学学报 2023年第2期42卷 191-200页

作者：杜抱朴殷钰喆谭伊张宇格范博姚植正郭航首都医科大学基础医学院人体解剖与组织胚胎学系北京100069 首都医科大学肿瘤与代谢性疾病研究室北京100069 首都医科大学基础医学院北京100069

本文对中国现代人群的两性身高差异分布状况及其影响因素进行了分析。选用152处中国现代人群(含69处汉族人群和83处少数民族人群)的男、女性身高数据,计算两性身高差异指数,并对比该指数在南、北方汉族和少数民族人群间的分布差异,同时... 详细信息

本文对中国现代人群的两性身高差异分布状况及其影响因素进行了分析。选用152处中国现代人群(含69处汉族人群和83处少数民族人群)的男、女性身高数据,计算两性身高差异指数,并对比该指数在南、北方汉族和少数民族人群间的分布差异,同时分析纬度、气候、体格大小与城乡环境因素对两性身高差异程度的影响。结果表明,中国男性的平均身高比女性高出约7.16%(4.72%~9.26%);南、北方汉族和少数民族之间的两性身高差异程度相似,北方汉族和南方汉族两性身高差异程度相似,但北方少数民族的两性身高差异明显大于南方少数民族。此外,两性身高差异程度与纬度、气温年较差和年均风速呈低度线性正相关,与年均气温、年均降水量和年均相对湿度呈低度线性负相关,而与体格大小和城乡环境并无显著关联。这提示遗传和自然环境因素在中国现代人群两性身高差异的区域化演变中更趋主导性,而社会环境因素的影响程度相对较低。

关键词：现代人中国人身高性别二态环境

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