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Comparison of Submicron Particles at a Rural and an Urban Site in the North China Plain during the December 2016 Heavy Pollution Episodes

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Journal of Meteorological Research 2018年第1期32卷 26-37页

作者： Xiaojing SHEN Junying SUN Xiaoye zhang Yangmei zhang yaqiang WANG Kaiyan TAN Peng WANG Lu zhang Xuefei QI Haochi CHE Zhouxiang zhang Junting ZHONG Huarong ZHAO Sanxue REN State Key Laboratory of Severe Weather/Key Laboratory of Atmospheric Chemistry of China Meteorological Administration Chinese Academy of Meteorological Sciences Integrated Ecological–Meteorological Observation and Experimental Station Chinese Academy of Meteorological Sciences Longfengshan Atmospheric Background Regional Station Heilongjiang Provincial Meteorological Bureau

An extensive field experiment for measurement of physical and chemical properties of aerosols was conducted at an urban site in the Chinese Academy of Meteorological Sciences（CAMS） in Beijing and at a rural site in Gucheng（GC）, Hebei Province in December 2016. This paper compares the number size distribution of submicron particle matter（PM1, diameter 〈 1 μm） between the two sites. The results show that the mean PM1 number concentration at GC was twice that at CAMS, and the mass concentration was three times the amount at CAMS. It is found that the accumulation mode（100–850 nm） particles constituted the largest fraction of PM1 at GC, which was significantly correlated with the local coal combustion, as confirmed by a significant relationship between the accumulation mode and the absorption coefficient of soot particles. The high PM1 concentration at GC prevented the occurrence of new particle formation（NPF） events, while eight such events were observed at CAMS. During the NPF events, the mass fraction of sulfate increased significantly, indicating that sulfate played an important role in NPF. The contribution of regional transport to PM1 mass concentration was approximately 50% at both sites, same as that of the local emission. However, during the red-alert period when emission control took place, the contribution of regional transport was notably higher.

关键词： particle number size distribution new particle formation severe haze-fog events Beijing-Tianjin-Hebei area Jing-Jin-Ji region submicron particles

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Relative Contributions of Boundary-Layer Meteorological Factors to the Explosive Growth of PM2.5 during the Red-Alert Heavy Pollution Episodes in Beijing in December 2016

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Journal of Meteorological Research 2017年第5期31卷 809-819页

作者： junting zhong xiaoye zhang yaqiang wang junying sun yangmei zhang jizhi wang kaiyan tan xiaojing shen haochi che lu zhang zhouxiang zhang xuefei qi huarong zhao sanxue ren yang li state key laboratory of severe weather/key laboratory of atmospheric chemistry of china meteorological administration chinese academy of meteorological sciencesBeijing 100081 center for excellence in regional atmospheric environment institute of urban environmentchinese academy of sciencesBeijing 100081 integrated ecologica–meteorological observation and experimental station chinese academy of meteorological sciencesXiamen 361021 center for atmosphere watch and service meteorological observation centerchina meteorological administrationBeijing 100081

Based on observations of urban mass concentration of fine particulate matter smaller than 2.5 μm in diameter （PM2.5）, ground meteorological data, vertical measurements of winds, temperature, and relative humidity （RH）, and ECMWF reanalysis data, the major changes in the vertical structures of meteorological factors in the boundary layer （BL） during the heavy aerosol pollution episodes （HPEs） that occurred in winter 2016 in the urban Beijing area were analyzed. The HPEs are divided into two stages： the transport of pollutants under prevailing southerly winds, known as the transport stage （TS）, and the PM2.5 explosive growth and pollution accumulation period characterized by a temperature inversion with low winds and high RH in the lower BL, known as the cumulative stage （CS）. During the TS, a surface high lies south of Beijing, and pollutants are transported northwards. During the CS, a stable BL forms and is characterized by weak winds, temperature inversion, and moisture accumulation. Stable atmospheric stratifica- tion featured with light/calm winds and accumulated moisture （RH 〉 80%） below 250 m at the beginning of the CS is closely associated with the inversion, which is strengthened by the considerable decrease in near-surface air temperat- ure due to the interaction between aerosols and radiation after the aerosol pollution occurs. A significant increase in the PLAM （Parameter Linking Aerosol Pollution and Meteorological Elements） index is found, which is linearly re- lated to PM mass change. During the first 10 h of the CS, the more stable BL contributes approximately 84% of the explosive growth of PM2.5 mass. Additional accumulated near-surface moisture caused by the ground temperature de- crease, weak turbulent diffusion, low BL height, and inhibited vertical mixing of water vapor is conducive to the sec- ondary aerosol formation through chemical reactions, including liquid phase and heterogeneous reactions, which fur- ther increases the PM2.5 concentration

关键词： explosive growth of PM2.5 pollutant transport anomalous temperature inversion moisture accumula-tion light or calm winds

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Orchestrated cellular,biochemical,and biomechanical optimizations endow platelet-rich plasma-based engineered cartilage with structural and biomechanical recovery

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Bioactive Materials 2021年第11期6卷 3824-3838页

作者： Ketao Wang Ji Li Yuxing Wang yaqiang Wang Yuanyuan Qin Fei Yang Mingzhu zhang Heng Zhu Zhongli Li Department of Orthopedics Chinese PLA General HospitalHaidianBeijing100853China Beijing Institute of Radiation Medicine/Beijing Institute of Basic Medical Sciences HaidianBeijing100850China Department of Foot and Ankle Beijing Tongren HospitalCapital Medical UniversityBeijing100730China Beijing National Laboratory for Molecular Sciences Institute of ChemistryChinese Academy of SciencesBeijing100190China Department of Orthopedic Surgery Zhongshan HospitalFudan UniversityShanghai200032China Department of Blood Transfusion Chinese PLA General HospitalHaidianBeijing100853China

Recently,biomaterials for cartilage regeneration has been intensively ***,the development of scaffolds that capture regenerated cartilage with biomechanical and structural recovery has rarely been *** address this challenge,platelet-rich plasma(PRP)-based cartilage constructs with a well-orchestrated symphony of cellular,biochemical and biomechanical elements were prepared by simultaneously employing chondrogenic progenitor cells(CPCs)as a cell source,optimizing platelet concentration,and adding an enzyme-ion *** was shown that this triple-optimized PRP+CPC construct possessed increased biomechanical properties and suitable biochemical *** following in vitro study demonstrated that the triple-optimized PRP+CPC constructs generated cartilage-like tissue with higher expression levels of chondrogenic-specific markers,more deposition of cartilage-specific extracellular matrix(ECM),and greater biomechanical values than those of the other *** weeks after the construct was implanted in a cartilage defect in vivo,histological analysis,qPCR,and biomechanical tests collectively showed that the triple-optimized constructs yielded a more chondrocyte-like cell phenotype with a higher synthesis of Col-Ⅱand *** importantly,the triple-optimized constructs facilitated cartilage regeneration with better biomechanical recovery than that of the other *** results demonstrate the efficacy of the triple-optimization strategy and highlight the simplicity and potency of this PRP+CPC construct for cartilage regeneration.

关键词： Platelet-rich plasma Cartilage regeneration Structural recovery Biomechanical recovery

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孕穗-抽穗期高温下有机肥配合氮肥调控对糯稻产量和品质的影响

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浙江农业科学 2024年第4期65卷 854-858页

作者：王保君程旺大沈亚强陈贵张红梅嘉兴市农业科学研究院生态环境研究所浙江嘉兴314016 嘉兴市农业科学研究院生物技术研究所浙江嘉兴314016

为了明确孕穗-抽穗期高温下有机肥配合氮肥调控对糯稻产量和品质的影响,通过随机区组试验,设置有机肥配合常规氮肥运筹(基肥∶分蘖肥∶穗肥=4∶3∶3,CK)、有机肥配合蘖肥前移(基肥∶分蘖肥∶穗肥=5∶2∶3,T-CK)、有机肥配合穗肥前移(基... 详细信息

为了明确孕穗-抽穗期高温下有机肥配合氮肥调控对糯稻产量和品质的影响,通过随机区组试验,设置有机肥配合常规氮肥运筹(基肥∶分蘖肥∶穗肥=4∶3∶3,CK)、有机肥配合蘖肥前移(基肥∶分蘖肥∶穗肥=5∶2∶3,T-CK)、有机肥配合穗肥前移(基肥∶分蘖肥∶穗肥=5∶3∶2,P-CK)3个处理,结合2022年浙江省极端高温天气情况(糯稻抽穗前15 d中最高气温达到35℃以上的天数有13 d,最高气温连续超35℃的天数为12 d,危害热积温为36℃,热害强度等级为重度),研究孕穗-抽穗期高温下有机肥配合氮肥调控对糯稻产量和品质的影响。研究表明:糯稻的热害损失率同糯稻的结实率呈显著负相关。同CK相比,T-CK的穗粒数显著增加了88.0%,直链淀粉含量显著降低了50%;P-CK籽粒蛋白质含量显著降低了2.10%。在热害损失率方面,P-CK的热害损失率最低。综上所述,有机肥配合穗肥前移(基肥∶分蘖肥∶穗肥=5∶3∶2)可以缓解糯稻孕穗-抽穗期高温热害胁迫。

关键词：糯稻氮肥高温热害品质

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癃清片治疗慢性前列腺炎多中心双盲安慰剂对照试验研究

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中国男科学杂志 2010年第9期24卷 21-25页

作者：高筱松高文喜贺菊乔屈淼林王传航强万明张亚强中国中医科学院广安门医院北京100053 湖北省中医院湖南中医药大学第一附属医院河南中医学院第一附属医院卫生部中日友好医院天津医科大学总医院

目的评价癃清片治疗慢性前列腺炎的有效性和安全性。方法多中心、随机、双盲、安慰剂对照临床设计。480例湿热兼瘀血型慢性前列腺炎患者按3:1的比例随机分为治疗组、安慰剂对照组。治疗组360例,口服癃清片,一次6片,每日2次。安慰剂对照... 详细信息

目的评价癃清片治疗慢性前列腺炎的有效性和安全性。方法多中心、随机、双盲、安慰剂对照临床设计。480例湿热兼瘀血型慢性前列腺炎患者按3:1的比例随机分为治疗组、安慰剂对照组。治疗组360例,口服癃清片,一次6片,每日2次。安慰剂对照组1 20例,服用安慰剂,一次6片,每日2次,疗程为4周。以美国国立卫生院前列腺炎症状评分(NIH-CPSI)、慢性前列腺炎中医证候评分作为主要疗效评价指标。结果 (1)治疗4周后,治疗组和对照组CPSI评分分别为(11.9±5.04)和(17.66±4.92),(P0.05)。结论癃清片治疗慢性前列腺炎安全、有效,值得在临床推广。

关键词：癃清片前列腺炎多中心研究

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Magnetic-electric composite coating with oriented segregated structure for enhanced electromagnetic shielding

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Journal of Materials Science & Technology 2022年第1期96卷 11-20页

作者： Jijun zhang Zexuan Wang Jiawei Li yaqiang Dong Aina He Guoguo Tan Qikui Man Bin Shen Junqiang Wang Weixing Xia Jun Shen Xin-min Wang CAS Key Laboratory of Magnetic Materials and Devices and Zhejiang Province Key Laboratory of Magnetic Materials and Application TechnologyNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054China University of Chinese Academy of Sciences Beijing 100049China Ningbo Key Laboratory of Polymer Materials Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China College of Mechatronics and Control Engineering Shenzhen UniversityShenzhen 518060China

Manipulation of the internal architecture is essential for electromagnetic interference(EMI)shielding performance of metal-based coatings,which can address the electromagnetic pollution in large-size,complex geometries,and harsh *** this work,oriented segregated structure with conductive networks embedded in magnetic matrix was achieved in Fe-based amorphous coatings via Ni-Cu-P functionalization of(Fe_(0.76)Si_(0.09)B_(0.1)P_(0.05))_(99)Nb_(1)amorphous powder precursors and then thermal spraying them onto aluminum(Al)*** from the unique magnetic-electric structure,the coating@Al composite delivered prominent EMI shielding *** EMI shielding effectiveness(SE)of modified coating@Al composite is~41 dB at 8-12 GHz,doubling the value of Al substrate and is 15 dB greater than that of Ni-Cu-P-free coating@Al *** analysis showed that the introduced Ni−Cu−P insertions forcefully suppress the serious oxidation of the magnetic precursors during thermal spraying and form a dense conductive network in the magnetic *** holography observation and electromagnetism simulation clarified that the modified coating can effectively trap and attenuate the incident radiations because of the electric loss from Ni−Cu−P conductive network,magnetic loss from Fe-based amorphous coating,and the electromagnetic interactions in the oriented segregated ***,the optimized thermal isolation and mechanical properties brought by structural improvement enable the coating to shield complex parts in thermal shock and mechanical loading *** work gives an insight on the design strategies for metal-based EMI shielding materials and enriches the fundamental understanding of EMI shielding mechanisms.

关键词： Fe-based amorphous coatings Ni-Cu-P Oriented segregated structure Electromagnetic shielding

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Elucidating the role of P on Mn-and N-doped graphene catalysts in promoting oxygen reduction:Density functional theory studies

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SusMat 2023年第3期3卷 390-401页

作者： yaqiang Li Penghui Ren Xiangyu Lu Jinqiu zhang Peixia Yang Xiaoxuan Yang Guangzhao Wang Anmin Liu Gang Wu Maozhong An State Key Laboratory of UrbanWater Resource and Environment School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbinChina Department of Chemical and Biological Engineering University at BuffaloThe State University of New YorkBuffaloNew YorkUSA Key Laboratory of Extraordinary Bond Engineering and Advanced Materials Technology of Chongqing School of Electronic Information EngineeringYangtze Normal UniversityChongqingChina State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalianChina

The non-noble Mn coordinated N,P co-doping graphene materials were investigated theoretically in this work based on density functional theory *** electronic structure is effectively tuned after the introduction of P *** moderate d band center and density of states at Fermi energy of MnN_(4)-P1-G indicate that it is ofmodest adsorption ability for these O-containing *** rank of adsorption energies ofO-containing intermediates for MnN_(4)-P1-G is OH*>2OH*>OOH*>O*>O2*>H2O*,whereas the MnN_(4)-P1-G favors a four-electron process instead of two-electron *** doping of P on MnN_(4)-P1-G can increase the kinetic activity for the rate-determining step as well as the Ulim for MnN_(4)-P1-G significantly increases from 0.38 to 0.45 V compared with MnN_(4)-*** spin density and magnetic moments of Mn are effectively tuned by d,p hybridization to lower the adsorption energy ofOHintermediates(rate-determining step[RDS])so as to improve the catalytic *** is concluded that the P-doped MnN_(4)catalysts with excellent oxygen reduction reaction activity can be obtained and this study can provide theoretical guidance for the rational design of high-performanceMn-based carbonmaterials catalysts.

关键词： MnN_(4)graphene oxygen reduction reaction P doping

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术后风险预测任务的结构化数据生成方法

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计算机与数字工程 2024年第1期52卷 51-59页

作者：罗晓辉周瑞豪张伟义舒红平王亚强郝学超成都信息工程大学软件工程学院成都610225 成都信息工程大学数据科学与工程研究所成都610225 成都信息工程大学软件自动生成与智能服务实验室成都610225 四川大学华西医院麻醉手术中心成都610044

近年来,医学领域越来越重视使用多中心数据共享的方式来提高模型的泛化能力。然而,共享医疗数据有隐私暴露的风险。类别不平衡也是使用术前结构化数据预测术后风险的一个挑战,它严重影响了模型的预测性能。这两个问题限制了术前数据的... 详细信息

近年来,医学领域越来越重视使用多中心数据共享的方式来提高模型的泛化能力。然而,共享医疗数据有隐私暴露的风险。类别不平衡也是使用术前结构化数据预测术后风险的一个挑战,它严重影响了模型的预测性能。这两个问题限制了术前数据的共享以及分类器在术后风险预测的效果。为了解决这些问题,论文提出了一种新的方法,使用生成对抗网络生成与真实数据相似的数据,用于训练分类模型和数据共享。实验证明生成对抗网络能生成高质量的数据。生成数据在特征分布上与真实数据高度相似,且用于术后风险预测后能有效提升术后风险预测的效果。此外,实验还验证了生成数据的隐私性,这为学术研究中的数据共享提供了新的可能性。

关键词：数据不平衡生成对抗网络术后并发症预测表格数据数据共享

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基于时空信息分段融合模型的术中低血压预测

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计算机与数字工程 2024年第1期52卷 35-42页

作者：吴少峰周瑞豪郝学超张伟义舒红平王亚强朱涛成都信息工程大学软件工程学院成都610225 成都信息工程大学数据科学与工程研究所成都610225 成都信息工程大学软件自动生成与智能服务四川省重点实验室成都610225 四川大学华西医院麻醉手术中心成都610044

准确提前预测术中低血压的发生对术中选择紧急方案以及降低患者术后的不良风险和死亡率具有积极作用。术中低血压预测目前主要基于术中患者的各项生理指标数据,但现有方法未能充分考虑多指标间的时间信息和空间信息。针对以上问题,提出... 详细信息

准确提前预测术中低血压的发生对术中选择紧急方案以及降低患者术后的不良风险和死亡率具有积极作用。术中低血压预测目前主要基于术中患者的各项生理指标数据,但现有方法未能充分考虑多指标间的时间信息和空间信息。针对以上问题,提出基于时空信息分段融合模型的术中低血压预测,先使用全卷积网络或残差网络提取局部空间信息,再使用门控循环单元提取时间信息并进行预测。通过对比术中低血压预测常用的深度神经网络模型,在原始和填补的临床数据的术中低血压预测中,不仅提高了低血压事件的预测准确性,还在面对数据填补时表现出一定的容忍度,能够应对噪声和不确定性的影响。

关键词：术中低血压时空信息信息融合

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CHARACTERISTICS OF CLAY MINERALS IN ASIAN DUST AND THEIR ENVIRONMENTAL SIGNIFICANCE

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China Particuology 2005年第5期3卷 260-264页

作者： Zhenxing Shen Xuxiang Li Junji Cao Sandrine Caquineau yaqiang Wang Xiaoye zhang Department of Environmental Science and Engineering Xi'an Jiaotong University Xi'an 710049 P. R. China Institute of Earth Environment Chinese Academy of Sciences Xi'an 710075 P. R. China Institut de Recherche pour le Developpement 32 av. H. Varagnat 93143 Bondy cedex France Chinese Academy of Meteorological Sciences Beijing 100081 P. R. China

The objectives of this research were to characterise the clay minerals composition of soil-derived dust in Northern China and to set up a mineralogical signature to trace their origin. Mineral composition of aerosol particles was investigated at Aksu, Dunhuang, Yulin, Tongliao and Changwu during an intensive field campaign period of ACE-Asia. The results show that the kaolinite （K） to chlorite （C） ratio is sensitive to the regional origin of Asian dust. Western source areas （represented by Aksu） displayed the lowest K/C ratio of 0.3 （average）, while it was found to increase up to 0.70 （average） upon moving towards northern source areas （represented by Yulin）. By studying transported dust in a deposition area representative of the Chinese Loess Plateau, the usefulness of the K/C ratio, when associated with back air-mass trajectories, was found to lie in revealing the origin of the dust. Comparison of the mineralogical data between Asian dust and Sahara dust, shows that the K/C ratio is also an effective signature to identify the source areas on a hemisphere scale.

关键词： soil dust clay ratios source identification

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