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Characterization of submicron aerosols in the urban outflow of the central Pearl River Delta region of China

Frontiers of Environmental Science & Engineering 2012年第5期6卷 725-733页

作者： zhaoheng gong Zijuan LAN Lian XUE Liwu ZENG Lingyan HE Xiaofeng HUANG Key Laboratory for Urban Habitat Environmental Science and Technology School of Environment and EnergyPeking University Shenzhen Graduate SchoolShenzhen 518055China Qingdao Environmental Monitoring Center Qingdao 266003China Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control School of Environmental Sciences and EngineeringNanjing University of Information Sciences and EngineeringNanjing 210044China

Submicron aerosol particles （with aerody- namic diameters less than 1 pm, PM1） were sampled and measured in Heshan, an urban outflow site of Guangzhou megacity in Pearl River Delta in South China, using an Aerodyne High-Resolution Time-of-Flight Aerosol Mass Spectrometer （HR-ToF-AMS） in November 2010 during 2010 Guangzhou Asian Games. The mean PM~ mass concentration measured was 47.9 ± 17.0 μg.m3 during the campaign, with organic aerosol （OA） and sulfate being the two dominant species, accounting for 36.3% and 20.9% of the total mass, respectively, followed by black carbon （17.1%, measured by an aethalometer）, nitrate （12.9%）, ammonium （9.6%） and chloride （3.1%）. The average size distributions of the species （except black carbon） were dominated by an accumulation mode peaking at -550 nm. Calculations based on high-resolution organic mass spectrum showed that, C, H, O and N on average contributed 58.1%, 7.3%, 30.7%, and 3.9% to the total organic mass, respectively. The average ratio of organic mass over organic carbon mass （OM/OC） was 1.73 ± 0.08. Four components of OA were identified by the Positive Matrix Factorization （PMF） analysis, including a hydro- carbon-like （HOA）, a biomass burning （BBOA） and two oxygenated （SV-OOA and LV-OOA） organic aerosol components, which on average accounted for 18.0%, 14.3%, 28.8% and 38.9% of the total organic mass, respectively.

关键词： organic aerosol high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) positive matrix factorization

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Source apportionment and secondary organic aerosol estimation of PM_(2.5) in an urban atmosphere in China

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Science China Earth Sciences 2014年第4期57卷 1352-1362页

作者： HUANG XiaoFeng YUN Hui gong zhaoheng LI Xiang HE LingYan ZHANG YuanHang HU Min Key Laboratory for Urban Habitat Environmental Science and Technology School of Environment and Energy Peking University Shenzhen Graduate School State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and EngineeringPeking University

PM2.5 is the key pollutant in atmospheric pollution in *** new national air quality standards taking effect,PM2.5 has become a major issue for future pollution *** effectively prevent and control PM2.5,its emission sources must be precisely and thoroughly ***,there are few publications reporting comprehensive and systematic results of PM2.5 source apportionment in the *** on PM2.5 sampling during 2009 in Shenzhen and follow-up investigation,positive matrix factorization(PMF)analysis has been carried out to understand the major sources and their temporal and spatial *** results show that in urban Shenzhen(University Town site),annual mean PM2.5 concentration was 42.2μg m?3,with secondary sulfate,vehicular emission,biomass burning and secondary nitrate as major sources;these contributed30.0%,26.9%,9.8%and 9.3%to total PM2.5,*** sources included high chloride,heavy oil combustion,sea salt,dust and the metallurgical industry,with contributions between 2%–4%.Spatiotemporal variations of various sources show that vehicular emission was mainly a local source,whereas secondary sulfate and biomass burning were mostly *** nitrate had both local and regional *** of secondary organic aerosol(SOA)has always been difficult in aerosol source *** this study,the PMF model and organic carbon/elemental carbon(OC/EC)ratio method were combined to estimate SOA in *** results show that in urban Shenzhen,annual SOA mass concentration was 7.5μg m?3,accounting for 57%of total organic matter,with precursors emitted from vehicles as the major *** work can serve as a case study for further in-depth research on PM2.5 pollution and source apportionment in China.

关键词： PM2.5 source apportionment secondary organic aerosol(SOA)

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含未检出值的环境监测数据集的处理方法

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环境科学学报 2009年第7期29卷 1345-1350页

作者：王斌朱雷宫照恒王戎陶澍地表过程分析与模拟教育部重点实验室北京大学城市与环境学院北京100871 北京大学环境科学与工程学院北京100871

环境样品分析过程中经常遇到包含未检出值的数据集,这在对含有微量金属和微量有机污染物样本的分析研究中更为常见.目前处理未检出数据的方法通常是忽略或者用0、检出下限的1/2或1/3进行简单替代.然而,当未检出数据比例较高时,忽略或简... 详细信息

环境样品分析过程中经常遇到包含未检出值的数据集,这在对含有微量金属和微量有机污染物样本的分析研究中更为常见.目前处理未检出数据的方法通常是忽略或者用0、检出下限的1/2或1/3进行简单替代.然而,当未检出数据比例较高时,忽略或简单替代可能给数据表征带来较大偏差,也不利于更深入的统计分析.为改善对包含未检出数据的分析效果,目前已经建立了多种统计方法.本文系统介绍了这些方法,包括总体均值和方差估计的参数和非参数方法以及关于均值的95%置信区间上界的估计方法.此外,本文利用虚拟数据和实测数据给出了主要方法的应用实例.

关键词：未检出数据低于检出下限数据处理

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ELECTRODEPOSITION OF NICKEL FROM ALL CHLORIDE ELECTROLYTE

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Transactions of Nonferrous Metals Society of China 1992年第3期2卷 46-52页

作者： gong Qian Liao Hong Yang Tao Hu Jiexue Fang zhaoheng Institute of Chemical Metallurgy Academia SinicaBeijing 100080China

The optimum operating conditions for the electrodeposition of nickel from all-nickel chloride electrolytes were studied,based on measurements of conductivity,surface tension,viscosity of nickel chloride electrolytes at different temperatures and concentrations of nickel chloride as well as the experiments of electrodeposition arranged using experimental design in the normal *** studying cathode polarization and examination of physical features of cathodic nickel,the effects of trace Fe,Co,Pb..TBP and N-235 in all-nickel chloride electrolyte on cathode potentials,cell voltages,current efficiency and energy consumption as well as the morphology and the internal stress of cathodic nickel in electrodeposition of nickel were examined.

关键词： electrodeposition nickel chloride

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Marine red yeast supplementation improves laying performance by regulating small intestinal homeostasis in aging chickens

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Animal Nutrition 2024年第3期18卷 177-190页

作者： Yudian Zhao Sujin Si Yangguang Ren Xing Wu Zihao Zhang Yixiang Tian Jing Li Yijie Li Meng Hou Xueyang Yao zhaoheng Xu Ruirui Jiang Xiangtao Kang Yujie gong Qiang Li Yadong Tian College of Animal Science and Technology Henan Agricultural UniversityZhengzhou 450046China Henan Key Laboratory for Innovation and Utilization of Chicken Germplasm Resources Zhengzhou 450046China Henan College of Animal Husbandry and Economics Zhengzhou 450046China College of Animal Science and Veterinary Medicine Henan Institute of Science and TechnologyXinxiang 453003China AB Vista Marlborough SN84ANUK

Recent studies have shown that age-related aging evolution is accompanied by imbalances in intestinal *** red yeast(MRY)is a functional probiotic that has been shown to have antioxidant,immune and other ***,we chose 900 healthy Hy-Line Brown hens at 433 d old as the research subjects and evaluated the correlation between intestinal health,laying performance,and egg quality in aged hens through the supplementation of *** laying hens were assigned into 5 groups and received diet supplementation with 0%,0.5%,1.0%,1.5%,and 2%MRY for 12 *** results showed that MRY supplementation increased egg production rate,average egg weight,and egg quality,and decreased feed conversion ratio and daily feed intake(P<0.05).The MRY supplement improved antioxidant indicators such as superoxide dismutase(SOD),catalase(CAT),glutathione peroxidase(GSH-Px),stimulated villus height,and increased the villus height to crypt depth ratio(V/C ratio)in the intestine(P<0.05).It also regulated the expression of intestinal inflammatory factors(transforming growth factor-β[TGF-β],interleukin[IL]-1β,IL-8,tumor necrosis factor-α[TNF-α])while increasing serum immunoglobulin G(IgG)levels(P<0.05).Furthermore,MRY supplementation upregulated the mRNA expression of tight junction proteins(occludin and zonula occludens-1[ZO-1]),anti-apoptotic gene(Bcl-2),and autophagy-related proteins(beclin-1 and light chain 3I[LC3I])in the intestine(P<0.05).The MRY supplement also led to an increase in the concentration of short-chain fatty acids in the cecum,and the relative abundance of the phylum Bacteroidetes,and genera Bacteroides and Rikenellaceae_RC9_gut_*** LEfSe analysis revealed an enrichment of Sutterella and Akkermansia *** conclusion,the results of this experiment indicated that the additional supplementation of MRY can improve the production performance of laying hens and may contribute to the restoration and balance of intestinal homeostasis,which sup

关键词： Marine red yeast Laying hen Senescence Intestinal homeostasis

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双能量CT心肌瘢痕量化预测陈旧性心肌梗死患者发生主要不良心血管事件风险

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中华放射学杂志 2024年第9期58卷 902-908页

作者：郭倩徐琦顾海蓉刘源超黄肇恒郑扣龙王天乐龚沈初祁荣兴南通市第一人民医院南通大学第二附属医院影像科南通226001 南通市第一人民医院南通大学第二附属医院心内科南通226001

目的利用双能量CT(DECT)后处理技术检测心肌瘢痕特征,探讨其对陈旧性心肌梗死(OMI)患者1年内发生主要不良心血管事件(MACE)的预测价值。方法连续纳入2019年11月至2022年10月在南通大学第二附属医院行冠状动脉CT血管成像随后行DECT心肌... 详细信息

目的利用双能量CT(DECT)后处理技术检测心肌瘢痕特征,探讨其对陈旧性心肌梗死(OMI)患者1年内发生主要不良心血管事件(MACE)的预测价值。方法连续纳入2019年11月至2022年10月在南通大学第二附属医院行冠状动脉CT血管成像随后行DECT心肌碘延迟强化(LIE-DECT)的OMI患者。所有入组患者图像采用40 keV单能谱+(Mono+)进行重建,在左心室短轴位图上LIE(代表心肌瘢痕)进行量化,包括LIE节段数、LIE评分及LIE程度。所有入组患者进行MACE随访,MACE定义为心力衰竭住院、恶性心律失常、心源性死亡。用回归分析探讨DECT心肌瘢痕量化值与MACE发生的关系,受试者操作特征曲线(ROC)评估心肌瘢痕量化值的预测MACE的效能,并使用DeLong检验比较组间差异。结果最终纳入OMI患者231例,LIE-DECT检查后1年内发生MACE 37例,占16.0%。发生MACE组LIE节段数5(4,7)个、LIE评分27(13,49)分、LIE程度9.4%(7.5%,15.5%)均高于未发生MACE组3(2,5)个、9(6,15)分、6.7%(6.3%,7.9%),差异具有统计学意义(Z值分别为5.57、6.23、5.90,P均<0.001)。多因素logistic回归分析显示,调整混杂因素后,LIE节段数(OR=2.118,P<0.001)、LIE评分(OR=3.168,P<0.001)及LIE程度(OR=3.092,P<0.001)仍与MACE发生显著相关。ROC曲线分析显示,LIE节段数、LIE评分及LIE程度曲线下面积分别为0.715、0.822、0.806(P均<0.001),灵敏度分别为81.1%、86.5%、91.9%,特异度分别为53.6%、69.6%、60.8%。DeLong检验显示,LIE评分、LIE程度预测效能高于LIE节段数(Z=2.63,P=0.008;Z=1.96,P=0.049),LIE评分与LIE程度预测效能差异无统计学意义(Z=0.60,P=0.551)。结论LIE-DECT 40 keV Mono+图检测的LIE节段数、LIE评分及LIE程度是OMI患者发生MACE的危险因素,且具有很好的预测MACE发生的效能,可作为评估OMI临床预后的重要指标。

关键词：体层摄影术,X线计算机心肌延迟强化心肌梗死主要心血管事件

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