检索结果-南通市图书馆

Submarine volcanism in the southern margin of the South China Sea

Journal of Oceanology and Limnology 2023年第2期41卷 612-629页

作者： Chenglong Zhang Shaohong XIA Chaoyan FAN Jinghe CAO CAS Key Laboratory of Ocean and Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China University of Chinese Academy of Sciences Beijing 100049China

Submarine volcanism is widely developed in the South China Sea(SCS).However,the characteristics,distribution,and genesis of submarine volcanoes in the southern margin of the SCS remain obscure.In this study,we analyzed the characteristics of submarine volcanoes and identified a total of 43 submarine volcanoes in the southern margin of the SCS,based on a newly acquired 310-km seismic reflection profile,along with previous 45 multi-channel seismic(MCS)profiles,petrological results from volcanic rocks sampled by dredging and drilling,nearby ocean bottom seismometer(OBS)wide-angle seismic profiles,and gravity and magnetic data.The study ascertains that most of these volcanoes are located in fault-block belts and graben-horst zones with strong crustal stretching and thinning.These volcanoes exhibit positive high-amplitude external seismic reflections,weak and chaotic internal seismic reflections,and are accompanied by local deformation of the surrounding sedimentary strata.Meanwhile,they have higher positive gravity anomalies and higher magnetic anomalies than the background strata.The petrological dating results show that volcanic ages are primarily in the Pliocene-Pleistocene,with geochemical characteristics indicating dominance of oceanic island basalt(OIB)-type alkali-basalts.Extensional faults have obviously spatial correspondence with post-spreading volcanism,suggesting these faults may provide conduits for submarine volcanism.The high-velocity bodies(HVBs)in the lower crust and magma underplating exist in the southern SCS,which could provide a clue of genesis for submarine volcanism.The inference is that the intensity of post-spreading volcanism in the southern margin might be affected by stretching faults,crustal thinning and magma underplating.

关键词： submarine volcanoes magmatism extensional fault Nansha Block South China Sea(SCS).

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Rural vehicle emission as an important driver for the variations of summertime tropospheric ozone in the Beijing-Tianjin-Hebei region during 2014-2019

引用

Journal of Environmental Sciences 2022年第4期34卷 126-135页

作者： Yifei Song Yuanyuan zhang Junfeng Liu Chenglong Zhang Chengtang Liu Pengfei Liu Yujing Mu Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Center for Excellence in Urban Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China

Tropospheric ozone(O_(3))pollution is increasing in the Beijing-Tianjin-Hebei(BTH)region despite a significant decline in atmospheric fine aerosol particles(PM_(2.5))in recent years.However,the intrinsic reason for the elevation of the regional O_(3)is still unclear.In this study,we analyzed the spatio-temporal variations of tropospheric O_(3)and relevant pollutants(PM_(2.5),NO_(2),and CO)in the BTH region based on monitoring data from the China Ministry of Ecology and Environment during the period of 2014-2019.The results showed that summertime O_(3)concentrations were constant in Beijing(BJ,0.06μg/(m^(3)·year))but increased significantly in Tianjin(TJ,9.09μg/(m^(3)·year))and Hebei(HB,6.06μg/(m3·year)).Distinct O_(3)trends between Beijing and other cities in BTH could not be attributed to the significant decrease in PM_(2.5)(from-5.08 to-6.32μg/(m3·year))and CO(from-0.053 to-0.090 mg/(m^(3)·year))because their decreasing rates were approximately the same in all the cities.The relatively stable O_(3)concentrations during the investigating period in BJ may be attributed to a faster decreasing rate of NO_(2)(BJ:-2.55μg/(m^(3)·year);TJ:-1.16μg/(m^(3)·year);HB:-1.34μg/(m3·year)),indicating that the continued reduction of NOx will be an effective mitigation strategy for reducing regional O_(3)pollution.Significant positive correlations were found between daily maximum8 hr average(MDA8)O_(3)concentrations and vehicle population and highway freight transportation in HB.Therefore,we speculate that the increase in rural NO_(x)emissions due to the increase in vehicle emissions in the vast rural areas around HB greatly accelerates regional O_(3)formation,accounting for the significant increasing trends of O_(3)in HB.

关键词： Tropospheric ozone The Beijing-Tianjin-Hebei region Spatio-temporal trends Rural vehicle emission

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Significant emission reductions of carbonaceous aerosols from residential coal burning by a novel stove

引用

Journal of Environmental Sciences 2022年第10期34卷 135-143页

作者： Xuran Li Chenglong Zhang Weimin Zhuo Yuxuan Zhuo Jincheng Yang Min Song Yujing Mu Research Center for Eco-Environmenta1l Sciences Chinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Center for Excellence in Urban Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Xuzhou Zhongkai Mechanical&Electrical Equipment Manufacturing Co. Ltd.Xuzhou 221300China School of Environmental Science and Engineering Shandong UniversityJinan 250100China

Carbonaceous aerosols(CA) are crucial components in the atmospheric PM_(2.5) and derived from diverse sources. One of the major sources for CA is from the incomplete combustion of bituminous coal that has been prevailingly used by household stoves in rural areas for heating during winter. To efficiently eliminate the CA emission, a new household stove(NHS) was developed based on a novel combustion technology and CA emissions from the NHS and a traditional household stove(THS) were comparably investigated under the actual stove operation conditions in a farmer’s house. Compared with the THS, the emission factors of organic carbon(OC), elemental carbon(EC), and water-soluble organic carbon(WSOC) from the NHS were reduced by 96%±1%, 98%±1%, and 91%±1% under the flaming process and 95%±1%, 96%±2%, and 83%±4% under the smoldering process, respectively. Additionally,the mass absorption efficiency of WSOC from the NHS reduced by 3 folds and the radiative forcing by WSOC relative to EC shrank remarkably by a factor of 3-8. Based on the reduction of emissions and light absorption of WSOC, the promotion of the NHS offers a possible solution to achieve the clean combustion of residential solid fuel.

关键词： OC EC WSOC Emission factor Light absorption

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Evaluation of offline sampling for atmospheric C3-C11 non-methane hydrocarbons

引用

Journal of Environmental Sciences 2022年第3期34卷 132-140页

作者： Zhiguo Liu Chengtang Liu Zhouming He Yujing Mu Chenglong Zhang Yuanyuan zhang Pengfei Liu Yuzheng Wang Junfeng Liu Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Center for Excellence in Urban Atmospheric Environment Institute of Regional EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China Clear Science&Technology Co. LtdBeijing 100029China

The concentration variation of C3-C11 non-methane hydrocarbons(NMHCs)collected in several types of commercial flexible bags and adsorption tubes was systematically inves-tigated using a gas chromatography-flame ionization detector(GC-FID)system.The per-centage loss of each NMHC in the polyvinyl fluoride(PVF)bags was less than 5%during a 7-hr storage period;significant NMHCs loss was detected in aluminum foil composite film and fluorinated ethylene propylene bags.The thermal desorption efficiency of NMHCs for adsorption tubes filled Carbopack B and Carboxen1000 sorbents was greater than 95%at 300℃,and the loss of NMHCs in the adsorption tubes during 20-days storage at 4℃was less than 8%.The thermal desorption efficiency for C11 NMHCs in the adsorption tube filled with Carbograph 1 and Carbosieve SⅢabsorbents was less than 40%at 300℃,and pyrolysis of the absorbents at 330℃interfered significantly with the measurements of some alkenes.The loss of alkenes was significant when NMHCs were sampled by cryo-enrichment at-90℃in the presence of O3 for the online NMHC measurements,and negligible for enrichment us-ing adsorption tubes at 25℃.Although O_(3)scrubbers have been widely used to eliminate the influence of O_(3)on NMHC measurements,the loss of NMHCs with carbon numbers greater than 8 was more than 10%.Therefore,PVF bags and adsorption tubes filled Carbopack B and Carboxen1000 sorbents were recommended for the sampling of atmospheric NMHCs.

关键词： Non-methane hydrocarbons(NMHCs) Gas chromatography-flame ionization detector(GC-FID) Offline sampling Adsorption tubes Ozone scrubber

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Characteristics and sources of peroxyacetyl nitrate(PAN)in the rural North China Plain:Results from1-year continuous observations

引用

Journal of Environmental Sciences 2024年第4期138卷 719-731页

作者： Xin Liu Xiaowei He Chenglong Zhang Yifei Song Shuyang Xie Chengtang Liu Pengfei Liu Yuanyuan zhang Yujing Mu Junfeng Liu Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

Peroxyacetyl nitrate(PAN)is an important photochemical pollutant in the troposphere,whereas long-term measurements are scarce in rural areas in North China Plain(NCP),resulting in unclear seasonal variations and sources of PAN in rural NCP.In this study,we conducted a 1-year observation of PAN during 2021-2022 at the rural NCP site.The average concentrations of PAN were 1.10,0.75,0.65,and 0.88 ppbv in spring,summer,autumn,and winter,respectively,with a 1-year average of 0.81±0.60 ppbv.Calculations indicate that the loss of PAN through thermal decomposition in summer accounts for 43.2% of the total formed PAN,which is an important reason for the low concentration of PAN in summer.We speculate that since the correlation between PAN and O_(3) in winter is significantly lower than that in other seasons,the observed regional transport of PAN cannot be ignored in winter.Through budget analysis,regional transport accounted for 12.8% and 55.9% of the observed PAN on the spring and winter pollution days,respectively,which showed that regional transport played key roles during the photochemical pollution of the rural NCP in winter.The potential source contribution function revealed that the transported PAN mainly comes from southern Hebei in spring.In winter,the transported PAN was mainly from Langfang,Hengshui,and southern Beijing.Our findings may aid in understanding PAN variations in different seasons in rural areas and highlight the impact of regional transport on the PAN budget.

关键词： Photochemical pollution Peroxyacetyl nitrate(PAN) Seasonal variations Regional transport Rural area

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Achieving Physical Layer Security Against Location Unknown Eavesdroppers via Friendly Jammer

引用

自动化学报:英文版 2023年第10期10卷 2038-2040页

作者： Heng zhang Jianwei Sun Xin Wang chenglong Gong School of Computer Engineering Jiangsu Ocean UniversityLianyungang 222000China School of Electronic Engineering Jiangsu Ocean UniversityLianyungang 222000China Shandong Provincial Key Laboratory of Computer Networks Shandong Computer Science CenterQilu University of TechnologyJinan 250014China

Dear Editor, This letter is concerning friendly jamming unmanned aerial vehicles(UAVs) to assist in the safe communication of UAV base stations. Due to the openness of UAV wireless communication, it is vulnerable to attacks leading to information disclosure or blockage. To address this issue, friendly jamming UAVs can assist UAV base stations and improve the security of wireless communications.

关键词： communication letter base

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Evolution of Biofilm and Its Effect on Microstructure of Mortar Surfaces in Simulated Seawater

引用

Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 234-243页

作者：荣辉 YU chenglong 张颖 School of Materials Science and Engineering Tianjin Chengjian UniversityTianjin 300384China Tianjin Key Laboratory of Building Green Functional Materials Tianjin Chengjian UniversityTianjin 300384China

To explore the role of biofilm formation on the corrosion of marine concrete structures, we investigated the attachment of biofilm on mortar surfaces in simulated seawater and the influence of biofilm on the microstructure of mortar surfaces. The results show that the evolution of biofilm on mortar surfaces in simulated seawater is closely related to the corrosion suffered by the mortar, and the process of biofilm attachment and shedding is continuous and cyclical. It is found that the specimens in the absence of biofilm attachment are more severely eroded internally by the corrosive medium in simulated seawater than those in the presence of biofilm attachment. For the specimens without biofilm attachment, after 60 days, gypsum forms,and after 120 days, the number of pores in the mortar is reduced. In contrast, for the specimens in the presence of biofilm attachment, gypsum could only be detected after 90 days, and fewer pores are filled. Therefore, the formation of biofilm could delay the invasion of the corrosive medium into the interior of mortar during the evolution of biofilm on mortar surfaces, mitigating the corrosion of mortars in seawater.

关键词： biofilm attachment mortar sulfur-oxidizing bacteria gypsum simulated seawater microstructure

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Photochemical production of carbonyl sulfide,carbon disulfide and dimethyl sulfide in a lake water

引用

Journal of Environmental Sciences 2017年第1期29卷 146-156页

作者： Qianqian Du Yujing Mu Chenglong Zhang Junfeng Liu Yuanyuan zhang Chengtang Liu Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Center for Excellence in Urban Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China

Photochemical production of carbonyl sulfide（COS）,carbon disulfide（CS_2） and dimethyl sulfide（DMS） was intensively studied in the water from the Aohai Lake of Beijing city.The lake water was found to be highly supersaturated with COS,CS_2 and DMS,with their initial concentrations of 0.91 ± 0.073 nmol/L,0.55 ± 0.071 nmol/L and 0.37 ± 0.062 nmol/L,respectively.The evident photochemical production of COS and CS_2 in the lake water under irradiation of 365 nm and 302 nm indicated that photochemical production of them might be the reason for their supersaturation.The similar dependence of wavelength and oxygen for photochemical production of COS,CS_2 and DMS implied that they might be from the same precursors.The water cage effect was found to favor COS production but inhibit CS_2and DMS formation,indicating that COS photochemical production was mainly from direct degradation of the precursors and the formation of CS_2 and DMS needed intermediates via combination of carbon-centered radicals and sulfur-centered radicals.The above assumptions were further confirmed by simulation experiments with addition of carbonyls and amino acids（cysteine and methionine）,and the photochemical formation mechanisms for COS,CS_2 and DMS in water were derived from the investigations.

关键词： Photochemical production Carbonyl sulfide Carbon disulfide Dimethyl sulfide Water

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Characteristics and anthropogenic sources of carbonyl sulfide in Beijing

引用

Journal of Environmental Sciences 2015年第2期27卷 163-170页

作者： Ye Cheng Chenglong Zhang Yuanyuan zhang Hongxing zhang Xu Sun Yujing Mu Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

Atmospheric mixing ratios of carbonyl sulfide（COS） in Beijing were intensively measured from March 2011 to June 2013. COS mixing ratios exhibited distinct seasonal variation, with a maximum average value of 849 ± 477 pptv in winter and a minimal value of 372 ± 115 pptv in summer. The seasonal variation of COS was mainly ascribed to the combined effects of vegetation uptake and anthropogenic emissions. Two types of significant linear correlations（R2〉 0.66） were found between COS and CO during the periods from May to June and from October to March, with slopes（ΔCOS/ΔCO） of 0.72 and 0.14 pptv/ppbv, respectively. Based on the emission ratios of COS/CO from various sources, the dominant anthropogenic sources of COS in Beijing were found to be vehicle tire wear in summer and coal burning in winter. The total anthropogenic emission of COS in Beijing was roughly estimated as 0.53 ± 0.02 Gg/year based on the local CO emission inventory and the ΔCOS/ΔCO ratios.

关键词： Carbonyl sulfide Anthropogenic sources Vehicle tire wire Coal combustion Carbon monoxide

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Trend detection and stochastic simulation prediction of streamflow at Yingluoxia hydrological station, Heihe River Basin, China

引用

Frontiers of Agricultural Science and Engineering 2017年第1期4卷 81-96页

作者： Chenglong Zhang Mo LI Ping GUO Center for Agricultural Water Research in China China Agricultural University

Investigating long-term variation and prediction of streamflow are critical to regional water resource management and planning. Under the continuous influence of climate change and human activity, the trends of hydrologic time series are nonstationary, and consequently the established methods for hydrological frequency analysis are no longer applicable. Five methods,including the linear regression, nonlinear regression,change point analysis, wavelet analysis and HilbertHuang transformation, were first selected to detect and identify the deterministic and stochastic components of streamflow. The results indicated there was a significant long-term increasing trend. To test the applicability of these five methods, a comprehensive weighted index was then used to assess their performance. This index showed that the linear regression was the best method. Secondly,using the normality test for stochastic components separated by the linear regression method, a normal distribution requirement was satisfied. Next, the Monte Carlo stochastic simulation technique was used to simulate these stochastic components with normal distribution, and thus a new ensemble hydrological time series was obtained by combining the corresponding deterministic components. Finally, according to these outcomes, the streamflow at different frequencies in 2020 was predicted.

关键词： Monte Carlo nonstationary trend detection streamflow prediction decomposition and ensemble Yingluoxia

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：