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A Measurement Study of Polluting a Large-Scale P2P IPTV System 被引量:1
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作者 王海舟 陈兴蜀 王文贤 《China Communications》 SCIE CSCD 2011年第2期95-102,共8页
With the rapid development of Peer-to-Peer(P2P) technology,IPTV applications based on that have received more and more attention from both industry and academia. Several applications using the data-driven mesh-pull ar... With the rapid development of Peer-to-Peer(P2P) technology,IPTV applications based on that have received more and more attention from both industry and academia. Several applications using the data-driven mesh-pull architectures raised and gained great success commercially. At present,PPLive system is one of the most popular instances of IPTV applications which attract a large number of users from across the globe. At the same time,however,the dramatic rise in popularity makes it more likely to become a vulnerable target. In this paper,we propose an effective measurement architecture,which is based on the peer's nature not only receiving polluted video chunks but also forwarding those to other peers,to measure the video streaming pollution attack and then use a dedicated crawler of PPLive developed by us to evaluate the impact of pollution in P2P live streaming. Specifically,the results show that a single polluter is capable of compromising all the system and its destructiveness is severe. 展开更多
关键词 peer-to-peer technology IPTV pollution attack PPLIVE MEASUREMENT
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The effect of detergent as polluting agent on the photosynthetic activity and chlorophyll content in bean leaves 被引量:1
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作者 Branislav R. Jovanic Srdjan Bojovic +2 位作者 Bratimir Panic Bozidar Radenkovic Marijana Despotovic 《Health》 2010年第5期395-399,共5页
The paper investigates effects of detergent for domestic use on the photosynthetic activity and chlorophyll content in intact bean leaves. The plants were watered for 21 days with a solution of domestic washing powder... The paper investigates effects of detergent for domestic use on the photosynthetic activity and chlorophyll content in intact bean leaves. The plants were watered for 21 days with a solution of domestic washing powder of 0.60 g r/l. It was established that the activity of photosynthetic apparatus in the plant leaf PhACNorm [%] decreases exponentially with the length of plant treatment/watering. At the end of the treatment (21st day) the activity of photosynthetic apparatus in the dosed plant leaf was no more than 45% of that in control plant (those which were not watered with detergent solution). With increased plant treatment duration the changed chlorophyll concentration ΔChlNorm [%] rose non-linearly in plant leaves. The highest change ΔChlNorm [%] was observed on the 21st day and amounted to 12%. 展开更多
关键词 CHLOROPHYLL DETERGENT Plant PHOTOSYNTHESIS pollution Water
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STUDY ON THE CHEMICAL CHARACTERISTICS OF POLLUTING FOG IN GUANGZHOU AREA IN SPRING 被引量:3
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作者 吴兑 李菲 +3 位作者 邓雪娇 毕雪岩 王新华 黄晓莹 《Journal of Tropical Meteorology》 SCIE 2009年第1期68-72,共5页
Samples of fog water collected in the area of Guangzhou during February, March and April of 2005 are used in this work to study the chemical composition of fog water in polluting fog there. Three typical episodes of p... Samples of fog water collected in the area of Guangzhou during February, March and April of 2005 are used in this work to study the chemical composition of fog water in polluting fog there. Three typical episodes of polluting fog are analyzed in terms of ionic concentration and their possible sources. It is found that the concentration of various ions in fog water is much higher than those in rainwater. Fog not only blocks visual range but contains liquid particles that result in high degree of pollution and are very harmful to human health. SO4= is the anion with the highest concentration in fog water, followed by NO3-. For the cation, Ca++ and NH4+ are the highest in concentration. It is then known that rainwater is more acidic than fog water, indicating that ionic concentration of fog water is much higher than that of rainwater, but there are much more buffering materials in fog water, like NH4+ and Ca++. There is significant enrichment of Ca++, SO4=, and Mg++ in fog water. In the Guangzhou area, fog water from polluting fog is mainly influenced continental environment and human activity. The episodes of serious fog pollution during the time have immediate relationships with the presence of abundant water vapor and large amount of polluting aerosol particles. 展开更多
关键词 Atmospheric chemistry polluting fog fog water chemical composition Guangzhou
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Remote sensing of air pollution incorporating integrated-path differential-absorption and coherent-Doppler lidar 被引量:2
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作者 Ze-hou Yang Yong Chen +5 位作者 Chun-li Chen Yong-ke Zhang Ji-hui Dong Tao Peng Xiao-feng Li Ding-fu Zhou 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期594-601,共8页
An innovative complex lidar system deployed on an airborne rotorcraft platform for remote sensing of atmospheric pollution is proposed and demonstrated.The system incorporates integrated-path differential absorption l... An innovative complex lidar system deployed on an airborne rotorcraft platform for remote sensing of atmospheric pollution is proposed and demonstrated.The system incorporates integrated-path differential absorption lidar(DIAL) and coherent-doppler lidar(CDL) techniques using a dual tunable TEA CO_(2)laser in the 9—11 μm band and a 1.55 μm fiber laser.By combining the principles of differential absorption detection and pulsed coherent detection,the system enables agile and remote sensing of atmospheric pollution.Extensive static tests validate the system’s real-time detection capabilities,including the measurement of concentration-path-length product(CL),front distance,and path wind speed of air pollution plumes over long distances exceeding 4 km.Flight experiments is conducted with the helicopter.Scanning of the pollutant concentration and the wind field is carried out in an approximately 1 km slant range over scanning angle ranges from 45°to 65°,with a radial resolution of 30 m and10 s.The test results demonstrate the system’s ability to spatially map atmospheric pollution plumes and predict their motion and dispersion patterns,thereby ensuring the protection of public safety. 展开更多
关键词 Differential absorption LIDAR COHERENT Doppler lidar Remoting sensing Atmospheric pollution
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Seasonal increase in nest defense,but not egg rejection,in a cuckoo host 被引量:1
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作者 Bo Zhou Wei Liang 《Avian Research》 SCIE CSCD 2024年第1期50-54,共5页
The interactions between avian brood parasites and their hosts provide an informative and easy-to-handle system for studying coevolution.Avian brood parasitism reduces the reproductive success of hosts,and thus,hosts ... The interactions between avian brood parasites and their hosts provide an informative and easy-to-handle system for studying coevolution.Avian brood parasitism reduces the reproductive success of hosts,and thus,hosts have evolved anti-parasitic strategies,such as rejecting parasitic eggs and adopting aggressive nest defense strategies,to avoid the cost brought on by brood parasitism.To test whether host anti-parasitic strategies are adjusted with the risk of being parasitized when the breeding seasons of brood parasites and hosts are not synchronous,we conducted a field experiment assessing nest defense and egg recognition behaviors of the Isabelline Shrike(Lanius isabellinus),a host of the Common Cuckoo(Cuculus canorus).In the local area,the host Isabelline Shrike begins to breed in April,whereas the summer migratory Common Cuckoo migrates to the local area in May and begins to lay parasitic eggs.Results showed that nest defense behaviors of the Isabelline Shrike increases significantly after cuckoo arrival,showing higher aggressiveness to cuckoo dummies,with no significant difference in attack rates among cuckoo,sparrowhawk and dove dummies,but their egg rejection did not change significantly.These results imply that Isabelline Shrikes may adjust their nest defense behavior,but not egg rejection behavior,with seasonality. 展开更多
关键词 AGGRESSION Anti-parasite strategy Egg rejection Mismatch cuckoo parasitism nest defense
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Tb^(3+)-nucleic acid probe-based label-free and rapid detection of mercury pollution in food 被引量:1
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作者 Xuhan Xia Chenxi Zhou +7 位作者 Yulin Zhu Yi Dong Qiang He Mohammad Rizwan Khan Yuanlong Chi Rosa Busquets Ruijie Deng Yao Ren 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期993-998,共6页
Mercury is a threatening pollutant in food,herein,we developed a Tb^(3+)-nucleic acid probe-based label-free assay for mix-and-read,rapid detection of mercury pollution.The assay utilized the feature of light-up fluor... Mercury is a threatening pollutant in food,herein,we developed a Tb^(3+)-nucleic acid probe-based label-free assay for mix-and-read,rapid detection of mercury pollution.The assay utilized the feature of light-up fluorescence of terbium ions(Tb^(3+))via binding with single-strand DNA.Mercury ion,Hg^(2+)induced thymine(T)-rich DNA strand to form a double-strand structure(T-Hg^(2+)-T),thus leading to fluorescence reduction.Based on the principle,Hg^(2+)can be quantified based on the fluorescence of Tb^(3+),the limit of detection was 0.0689μmol/L and the linear range was 0.1-6.0μmol/L.Due to the specificity of T-Hg^(2+)-T artificial base pair,the assay could distinguish Hg^(2+)from other metal ions.The recovery rate was ranged in 98.71%-101.34%for detecting mercury pollution in three food samples.The assay is low-cost,separation-free and mix-to-read,thus was a competitive tool for detection of mercury pollution to ensure food safety. 展开更多
关键词 Mercury pollution Food safety Nucleic acid probe LABEL-FREE TERBIUM
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Design and assembly of a nested imaging X-ray telescope for the Hot Universe Baryon Surveyor mission 被引量:1
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作者 Jun Yu Ruohui Xian +8 位作者 Xiaoqiang Wang Yifan Wang Zhanshan Wang Wei Zhang Yibo Cai Jing Yang Xi Lu Wei Wang Wei Cui 《Astronomical Techniques and Instruments》 CSCD 2024年第3期157-165,共9页
The Hot Universe Baryon Surveyor (HUBS) mission will carry a nested X-ray telescope capable of observing an energy range from 0.5 keV to 2 keV to study hot baryon evolution. In this paper, we report the latest progres... The Hot Universe Baryon Surveyor (HUBS) mission will carry a nested X-ray telescope capable of observing an energy range from 0.5 keV to 2 keV to study hot baryon evolution. In this paper, we report the latest progress in the design and construction of nested X-ray telescopes which were designed to use a three-stage conic-approximation type assembly to simplify the manufacturing process. The mirror substrate is made using the thermal glass slumping method, with mirrors characterized by a root-mean-square roughness of 0.3 nm, with expected high reflectivity and good thermal stability. We also discuss methods of telescope construction and conduct a deformation analysis of the manufactured mirror. The in situ measurement system program is developed to guide the telescope assembly process. 展开更多
关键词 nested X-ray telescope Thermal glass slumping Telescope assembly In situ measurement
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Ordered mesoporous materials for water pollution treatment:Adsorption and catalysis 被引量:1
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作者 Peng Zhang Mingming He +4 位作者 Wei Teng Fukuan Li Xinyuan Qiu Kexun Li Hao Wang 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第8期1239-1256,共18页
To meet the growing emission of water contaminants,the development of new materials that enhance the efficiency of the water treatment system is urgent.Ordered mesoporous materials provide opportunities in environment... To meet the growing emission of water contaminants,the development of new materials that enhance the efficiency of the water treatment system is urgent.Ordered mesoporous materials provide opportunities in environmental processing applications due to their exceptionally high surface areas,large pore sizes,and enough pore volumes.These properties might enhance the performance of materials concerning adsorption/catalysis capability,durability,and stability.In this review,we enumerate the ordered mesoporous materials as adsorbents/catalysts and their modifications in water pollution treatment from the past decade,including heavy metals(Hg^(2+),Pb^(2+),Cd^(2+),Cr^(6+),etc.),toxic anions(nitrate,phosphate,fluoride,etc.),and organic contaminants(organic dyes,antibiotics,etc.).These contributions demonstrate a deep understanding of the synergistic effect between the incorporated framework and homogeneous active centers.Besides,the challenges and perspectives of the future developments of ordered mesoporous materials in wastewater treatment are proposed.This work provides a theoretical basis and complete summary for the application of ordered mesoporous materials in the removal of contaminants from aqueous solutions. 展开更多
关键词 Water pollution treatment Ordered mesoporous materials Toxic contaminants ADSORPTION CATALYSIS
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Significant contributions of the petroleum industry to volatile organic compounds and ozone pollution:Insights from year-long observations in the Yellow River Delta 被引量:1
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作者 Jinghao Tang Hengqing Shen +7 位作者 Hong Li Yuanyuan Ji Xuelian Zhong Min Zhao Yuhong Liu Mingzhi Guo Fanyi Shang Likun Xue 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第6期39-44,共6页
The petroleum industry is a significant source of anthropogenic volatile organic compounds(VOCs),but up to now,its exact impact on urban VOCs and ozone(O_(3))remains unclear.This study conducted year-long VOC ob-serva... The petroleum industry is a significant source of anthropogenic volatile organic compounds(VOCs),but up to now,its exact impact on urban VOCs and ozone(O_(3))remains unclear.This study conducted year-long VOC ob-servations in Dongying,China,a petroleum industrial region.The VOCs from the petroleum industry(oil and gas volatilization and petrochemical production)were identified by employing the positive matrix factorization model,and their contribution to O_(3) formation was quantitatively evaluated using an observation-based chemical box model.The observed annual average concentration of VOCs was 68.6±63.5 ppbv,with a maximum daily av-erage of 335.3 ppbv.The petroleum industry accounted for 66.5%of total VOCs,contributing 54.9%from oil and gas evaporation and 11.6%from petrochemical production.Model results indicated that VOCs from the petroleum industry contributed to 31%of net O_(3) production,with 21.3%and 34.2%contributions to HO_(2)+NO and RO_(2)+NO pathways,respectively.The larger impact on the RO_(2) pathway is primarily due to the fact that OH+VOCs ac-count for 86.9%of the primary source of RO_(2).This study highlights the critical role of controlling VOCs from the petroleum industry in urban O_(3) pollution,especially those from previously overlooked low-reactivity alkanes. 展开更多
关键词 Petroleum industry Volatile organic compounds Ozone pollution Positive matrix factorization Observation-based model
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An Integrated Analysis on the Synergistic Reduction of Carbon and Pollution Emissions from China’s Iron and Steel Industry 被引量:1
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作者 Quanyin Tan Fei Liu Jinhui Li 《Engineering》 SCIE EI CAS CSCD 2024年第9期111-121,共11页
Decarbonization and decontamination of the iron and steel industry(ISI),which contributes up to 15%to anthropogenic CO_(2) emissions(or carbon emissions)and significant proportions of air and water pollutant emissions... Decarbonization and decontamination of the iron and steel industry(ISI),which contributes up to 15%to anthropogenic CO_(2) emissions(or carbon emissions)and significant proportions of air and water pollutant emissions in China,are challenged by the huge demand for steel.Carbon and pollutants often share common emission sources,indicating that emission reduction could be achieved synergistically.Here,we explored the inherent potential of measures to adjust feedstock composition and technological structure and to control the size of the ISI to achieve carbon emission reduction(CER)and pollution emission reduction(PER).We investigated five typical pollutants in this study,namely,petroleum hydrocarbon pollutants and chemical oxygen demand in wastewater,particulate matter,SO_(2),and NO_(x) in off gases,and examined synergies between CER and PER by employing cross elasticity for the period between 2022 and 2035.The results suggest that a reduction of 8.7%-11.7%in carbon emissions and 20%-31%in pollution emissions(except for particulate matter emissions)could be achieved by 2025 under a high steel scrap ratio(SSR)scenario.Here,the SSR and electric arc furnace(EAF)ratio serve critical roles in enhancing synergies between CER and PER(which vary with the type of pollutant).However,subject to a limited volume of steel scrap,a focused increase in the EAF ratio with neglection of the available supply of steel scrap to EAF facilities would lead to an increase carbon and pollution emissions.Although CER can be achieved through SSR and EAF ratio optimization,only when the crude steel production growth rate remains below 2.2%can these optimization measures maintain the emissions in 2030 at a similar level to that in 2021.Therefore,the synergistic effects between PER and CER should be considered when formulating a development route for the ISI in the future. 展开更多
关键词 Iron and steel industry Carbon and pollution emissions Synergistic reduction Technological structure Steel scrap Cross-elasticity
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Clarifying the relationship between PM2.5 and ozone complex pollution and synoptic patterns in a typical petrochemical city in the Bohai Rim region of China:Implications for air pollution forecasting and control 被引量:1
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作者 Yongxin Yan Cong An +7 位作者 Junling Li Yuanyuan Ji Rui Gao Hong Wang Fanyi Shang Linlin Ma Xiaoshuai Gao Hong Li 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第6期45-52,共8页
Meteorological conditions are vital to PM_(2.5)and ozone(O_(3))complex pollution.Herein,the T-mode principal com-ponent analysis method was employed to objectively classify the 925-hPa geopotential height field of Don... Meteorological conditions are vital to PM_(2.5)and ozone(O_(3))complex pollution.Herein,the T-mode principal com-ponent analysis method was employed to objectively classify the 925-hPa geopotential height field of Dongying from 2017 to 2022.Synoptic patterns associated with four pollution types-namely,PM_(2.5)-only pollution,O_(3)-only pollution,Co-occurring of PM_(2.5)and O_(3)pollution,Non-occurring of PM_(2.5)and O_(3)pollution-were characterized at different time scales.The results indicated that synoptic classes conducive to PM_(2.5)-only pollution were“high-pressure top front”,“offshore high-pressure rear”,and“high-pressure inside”,while those conducive to O_(3)-only pollution were“offshore high-pressure rear”,“subtropical high”,and“high and low systems”.The Co-occurring of PM_(2.5)and O_(3)pollution were influenced by high pressure,and the Non-occurring of PM_(2.5)and O_(3)pollution were linked to precipitation and strong northerly winds.The variation in dominant synoptic patterns is crucial in the frequency changes of the four pollution types,which was further validated through the analysis of typical cases.Under the favorable meteorological conditions of high-pressure control with strong northerly winds or a subtropical high and inverted trough both with strong precipitation,there is potential to achieve coordinated control of PM_(2.5)and O_(3)in Dongying.Additionally,measures like artificially manipulating local humidity could be adopted to alleviate pollution levels.This study reveals the importance of comprehending the meteorological factors contributing to the formation of PM_(2.5)and O_(3)complex pollution for the improvement of urban air quality in the Bohai Rim region of China when emissions are high and the concentration of air pollutants exhibits high meteorological sensitivity. 展开更多
关键词 Synoptic classification T-mode principal component analysis Complex air pollution Correlation analysis Bohai Rim region
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Upgrade of Transportation Infrastructure and Siting of Polluting Enterprises:The Case of High-Speed Railway Launch in China
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作者 Cai Hongbo Zhong Chao Han Jinrong 《China Economist》 2022年第3期89-112,共24页
With the quasi-natural experiment of the launching of high-speed railways in Chinese cities,this paper empirically investigated the effects of the upgrade of the transportation infrastructure on the site selection of ... With the quasi-natural experiment of the launching of high-speed railways in Chinese cities,this paper empirically investigated the effects of the upgrade of the transportation infrastructure on the site selection of polluting enterprises.We found that although the launching of a high-speed railway generally has a negative impact on the siting of polluting enterprises:(i)While there was a significant decrease in polluting enterprises of a private and other nature,the reduction in overseas-funded and state-owned enterprises was insignificant;(ii)while the launching of a high-speed railway greatly restrained the entry of polluting enterprises in the eastern region,large cities and more developed cities,this was followed by the movement of more polluting enterprises to the central and western regions,small and medium-sized cities and less developed cities;(iii)there was a significant decrease in polluting enterprises in environmentally conscious cities after the launching of a high-speed railway.This paper also found that infrastructure upgrade may influence the siting of polluting enterprises through the following:Environmental cleanness,factor concentration and spatial integration.Government authorities and market entities should be fully aware of and attach great importance to how the transportation infrastructure influences the site selection of businesses,as this is of great significance for China’s regional development planning,local business climate and investment planning,environmental protection,and other related policymaking initiatives. 展开更多
关键词 Transportation infrastructure high-speed railway polluting enterprises site selection
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Nest decoration:Black feathers prevent Crested Mynas from nest usurpation
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作者 Jinmei Liu Wei Liang 《Avian Research》 SCIE CSCD 2024年第2期292-297,共6页
Nests are important structures for birds to raise their offspring and for signaling.Many birds incorporate feathers into the nest,since feathers were traditionally thought to serve the function of insulation.Hypothese... Nests are important structures for birds to raise their offspring and for signaling.Many birds incorporate feathers into the nest,since feathers were traditionally thought to serve the function of insulation.Hypotheses in recent years have considered that some birds place feathers in conspicuous locations in the nest for decoration to trigger a fear response in the competitors.In this study,we investigated whether decorative feathers could deter nest usurpation by Crested Mynas(Acridotheres cristatellus)by manipulating nest box contents.The results revealed that Crested Mynas preferred black feathers to white feathers as decorations and occupied nest boxes decorated with black feathers significantly less than those decorated with white feathers,suggesting that black decorative feathers in the nest could be more effective in preventing nest usurpation by Crested Mynas and that white decorative feathers may have other functions.The black feathers in the nest are prominently placed at the edge of the nest to convey the message that“this nest is occupied”or“the owner of this nest has been preyed upon”to visitor Crested Mynas,thus effectively preventing them from usurping the nest at a later stage. 展开更多
关键词 Extended phenotype FEATHERS nest decoration nest usurpation
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Health risk assessment of heavy metal pollution in groundwater of a karst basin,SW China 被引量:1
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作者 Fu-ning Lan Yi Zhao +1 位作者 Jun Li Xiu-qun Zhu 《Journal of Groundwater Science and Engineering》 2024年第1期49-61,共13页
To investigate the presence of metal elements and assess their health risk for the populace in the Nandong Underground River Basin(NURB),we conducted an analysis of eleven common heavy metals in the water body.A Healt... To investigate the presence of metal elements and assess their health risk for the populace in the Nandong Underground River Basin(NURB),we conducted an analysis of eleven common heavy metals in the water body.A Health risk assessment(HRA)model was employed to analyze 84 water samples from the NURB.The detection results revealed the following order of heavy metals concentrations:Fe>Al>Mn>Zn>As>Cd>Pb>Cr>Ni>Cu>Hg.Correlation analysis indicated a certain similarity in material source and migration transformation among these eleven metal elements.Our study identified that the health risks for local residents exposed to metal elements in the water of NURB primarily stem from carcinogenic risk(10^(−6)–10^(−4)a^(−1))through the drinking water pathway.Moreover,the health risk of heavy metal exposure for children through drinking water was notably higher than for adults.The maximum health risks of Cr in both underground and surface water exceeded the recommendation standard(5.0×10^(−5)a^(−1))from ICRP,surpassing the values recommended by the Swedish Environmental Protection Agency,the Dutch Ministry of Construction and Environment and the British Royal Society(5.0×10^(−6)a^(−1)).The results of the health risk assessment indicate that Cr in the water of NURB is the primary source of carcinogenic risk for local residents,followed by Cd and As.Consequently,it is imperative to control these three carcinogenic metals when the water was used as drinking water resource. 展开更多
关键词 Water pollution Correlation Analysis Toxicity of Heavy Metal Elements Underground River Basin Carcinogenicity Potential
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Implementation of a Nesting Repair Technology for Transportation Pipeline Repair
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作者 Yijun Gao Yong Wang +2 位作者 Qing Na Jiawei Zhang Aixiang Wu 《Fluid Dynamics & Materials Processing》 EI 2024年第11期2443-2458,共16页
Filling methods in the mining industry can maximize the recovery of mineral resources and protect the underground and surface environments.In recent years,such methods have been widely used in metal mines where pipeli... Filling methods in the mining industry can maximize the recovery of mineral resources and protect the underground and surface environments.In recent years,such methods have been widely used in metal mines where pipeline transportation typically plays a decisive role in the safety and stability of the entirefilling system.Because thefilling slurry contains a large percentage of solid coarse particles,the involved pipeline is typically eroded and often damaged during such a process.A possible solution is the so-called nesting repair technology.In the present study,nesting a 127 mm outer diameter pipeline in 151 mm inner diameter borehole is considered to meet the repair objective.First,by using the rheological theory,the pipeline transmission resistance and self-flow conveying range are calculated under different working conditions.It is shown that the pipeline transmission resistance is larger when the inner diameter of casing is 80 mm,and the limitflow rate of vertical pipeline self-flow is 120 m^(3)/h;moreover,when the pipeline diameter is 100 mm and theflow rate is 140 m^(3)/h,the self-flow conveying can be satisfied in most of the underground−455 m stage.Accordingly,a plan is presented for the nesting repair strategy,based on the installation of a drill bit under the casing and lowering the casing into the borehole as if it were a drill pipe.Finally,the outcomes of such a strategy are verified.Thefillingflow rate range using the new pipelines is found to be in the range from 188.60 to 224.39 m^(3)/h,and its averagefillingflow rate reaches 209.83 m^(3)/h when conveying 2319.6 m long-distance quarry. 展开更多
关键词 BOREHOLE nesting repair pipeline transmission resistance flow rate
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Habitat preferences and nest site selection by sympatric populations of Middle Spotted Woodpecker(Dendrocoptes medius) and Syrian Woodpecker(Dendrocopos syriacus) in natural mountain forests of Southwest Iran
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作者 Arya Shafaeipour Jerzy Michalczuk Behzad Fathinia 《Avian Research》 SCIE CSCD 2024年第1期81-90,共10页
We examined habitat preferences and nesting requirements of sympatric populations of Middle Spotted Woodpecker(Dendrocoptes medius) and Syrian Woodpecker(Dendrocopos syriacus).We carried out our study in 2015–2018 in... We examined habitat preferences and nesting requirements of sympatric populations of Middle Spotted Woodpecker(Dendrocoptes medius) and Syrian Woodpecker(Dendrocopos syriacus).We carried out our study in 2015–2018 in natural mountain forests of Southwest Iran.We compared selected features of nesting,territory,and outside territory tree stands of the studied woodpeckers.The Middle Spotted Woodpecker occupied only oak forests,but the Syrian Woodpecker inhabited heterogenic forests that included the preferred tree of this species,the Mount Atlas Mastic.We recorded that in the breeding territories of the Middle Spotted Woodpecker,a greater area covered by tree crowns,as well as a larger number of trees,and a larger trunk basal area were observed in comparison to the territories occupied by the more plastic Syrian Woodpecker.Different habitat preferences demonstrated by both species could be a result of the selection of tree stands that provide the necessary food resources for each woodpecker species.Adaptation of Syrian Woodpecker to use heterogenic forest stands including tree species that produce fruits and as Mount Atlas Mastic trees,which likely allowed this species to colonise in Asia and Europe non-forest tree stands as orchards or gardens.Our results showed that poor tree condition and large tree trunk dimensions had a positive impact on the selection of nesting sites by both species.The presence of trees with large trunk dimensions was associated with multiple years of use of woodpecker breeding sites in the studied forests.Maintaining habitats in suitable condition for both studied woodpeckers can be achieved by preserving natural forests in the mountain regions of Iran. 展开更多
关键词 Habitat conservation nesting requirements Primary cavity nesters Species co-occurrence
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Pinus sylvestris and Picea abies canopy effects on deposition of air pollutants
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作者 ValentinasČerniauskas Iveta Varnagirytė‑Kabašinsk ienė +1 位作者 Valda Araminienė Vidas Stakėnas 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第4期34-46,共13页
Tree canopies influence atmospheric pollutant depositions depending on type,ecosystem characteristics,and local climatic conditions.This study investigated the impact of Pinus sylvestris L.and Picea abies(L.)H.Karst.,... Tree canopies influence atmospheric pollutant depositions depending on type,ecosystem characteristics,and local climatic conditions.This study investigated the impact of Pinus sylvestris L.and Picea abies(L.)H.Karst.,and a mixture of both,on the chemical composition of pre-cipitation.Three permanent plots within the ICP forest level Ⅱ monitoring network in Lithuania were selected to illustrate typical hemiboreal coniferous forests.The study analysed(1)the concentrations of NO_(2),NH_(3) and SO_(2) in the ambi-ent air;(2)the concentrations of SO_(4)^(2−),NO_(3)^(−),NH_(4)^(+),Na^(+),K^(+),Ca^(2+) and Cl^(-) in throughfall beneath canopies and in precipitation collected in an adjacent field,and(3)S and total N,Na^(+),K^(+),Ca^(2+)and Cl−depositions in throughfall and precipitation over 2006-2022.Results show a signifi-cant decrease in SO_(2) emissions in the ambient air;NO_(2) and NH_(3) emissions also decreased.The canopies reduced the acidity of throughfall,although they led to notably higher concentrations of SO_(4)^(2−),NO_(3)^(−),Na^(+),and particularly K^(+).During the study,low variability in NO_(3)^(-)deposition and a decrease in NH_(4)^(+)deposition occurred.Deposition loads increased by 20-30%when precipitation passed through the canopy.The cumulative deposition of S,Cl,Na,K,Ca,and N was greater under P.abies than under P.sylvestris.How-ever,K deposition in throughfall was considerably lower under P.sylvestris compared to the P.abies or mixed stand.Throughfall S depositions declined across all three coniferous plots.Overall,there was no specific effect of tree species on throughfall chemistry. 展开更多
关键词 PRECIPITATION THROUGHFALL Deposition of chemicals pollutION Lithuania
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Coordinated control of PM_(2.5)and O_(3):Investigating the physical and chemical processes underlying regional complex air pollution
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作者 Aijun Ding Meigen Zhang Likun Xue 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第6期1-2,共2页
Fine particulate matter(PM_(2.5))and ground-level ozone(O_(3))are the primary air pollutants that degrade air quality in urban and regional areas of China.Since the implementation of the“Air Pollution Preven-tion and... Fine particulate matter(PM_(2.5))and ground-level ozone(O_(3))are the primary air pollutants that degrade air quality in urban and regional areas of China.Since the implementation of the“Air Pollution Preven-tion and Control Action Plan”in 2013,ambient concentrations of PM_(2.5)have significantly decreased across China.However,O_(3)levels exhibited an upward trend until 2019 and have since remained elevated,despite the COVID-19 pandemic.Currently,no city in China has achieved the World Health Organization’s guidelines for PM_(2.5)(24-hour mean of 15μg m^(−3)and annual mean of 5μg m^(−3))and O_(3)(8-hour mean of 100μg m^(−3)).Therefore,more rigorous measures are necessary to alleviate PM_(2.5)and O_(3)pollution in China. 展开更多
关键词 China pollutION (3)
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Anthropogenic nesting materials and reproductive performance of Chinese Bulbuls(Pycnonotus sinensis)along the urbanization gradient in Hangzhou,China
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作者 Xingmin Chen Qin Zhang +3 位作者 Sisi Lan Qin Huang Shuihua Chen Yanping Wang 《Avian Research》 SCIE CSCD 2024年第4期431-437,共7页
Urbanization induced by human activities presents both challenges and adaptive opportunities for wildlife.One notable impact of urban sprawl is the vast amount of waste it produces,which has discernible effects on wil... Urbanization induced by human activities presents both challenges and adaptive opportunities for wildlife.One notable impact of urban sprawl is the vast amount of waste it produces,which has discernible effects on wildlife.Interestingly,an emerging trend has been observed that birds are incorporating anthropogenic materials into their nests.However,the relationship between anthropogenic nesting materials(ANMs)and the reproductive performance of urban birds is unclear.In this study,we investigated the relationship between the incorporation of ANMs into nests and the reproductive performance of Chinese Bulbuls(Pycnonotus sinensis)by monitoring and collecting data on 136 breeding nests in Hangzhou,China.We gathered data on seven reproductive traits of Chinese Bulbuls,including laying date,incubation period,nestling period,clutch size,egg volume,hatching success rate,and fledging success rate.We then calculated the urbanization synthetic index as a measure of the level of urbanization and examined its relationship with the proportion and weight of ANMs.Through examination of nest components,we observed significant increase in the proportion and weight of ANMs with the urbanization synthetic index.Notably,we found a higher hatching success rate of Chinese Bulbuls with an increasing proportion of ANMs.However,the inclusion of ANMs in nests was not correlated with other reproductive traits of Chinese Bulbuls.Overall,the use of ANMs by Chinese Bulbuls is consistent with the adaptive hypothesis and the availability hypothesis.Further studies should use controlled experiments to investigate the impact of ANMs on avian reproductive success. 展开更多
关键词 Adaptive hypothesis Anthropogenic nesting materials Availability hypothesis Hatching success Reproductive traits URBANIZATION
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Kentish Plover(Charadrius alexandrinus) and Little Tern(Sternula albifrons) prefer shells for nesting:A field experiment
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作者 Macarena Castro Andrés De la Cruz +1 位作者 Nuria Martin-Sanjuan Alejandro Pérez-Hurtado 《Avian Research》 SCIE CSCD 2024年第1期55-59,共5页
Shorebird populations are declining worldwide,mainly due to human disturbances and loss of coastal wetlands.However,supratidal habitats as saltpans could play a role in buffering human impact.Saltpans have shown to be... Shorebird populations are declining worldwide,mainly due to human disturbances and loss of coastal wetlands.However,supratidal habitats as saltpans could play a role in buffering human impact.Saltpans have shown to be important as feeding or breeding sites of some shorebird species.A potential conservation strategy to increase shorebird populations in saltpans is to manipulate the cues that birds use to select optimal breeding habitat.Here it is hypothesized that shorebirds are attracted to bivalve shells due to the advantages they offer.Following this hypothesis,we supplemented a restored saltpan in 2019 and 2021 with bivalve shells,expecting an increase in the number of breeding birds’ nests.More than 75% of Kentish Plover(Charadrius alexandrinus) and Little Tern(Sternula albifrons) nests were found in patches with shells in both years.The best model for both species indicates that the presence of shells is the factor that most correlates with the location of nests.The probability of choosing one place over another to settle their nest increases in areas with an abundance of shells,double in the case of the Kentish Plover and triple in the case of the Little Tern.The result of this study may constitute a valuable tool for attracting birds to restored saltpans and could contribute to the success of expensive restoration projects where time is usually a constraint. 展开更多
关键词 Habitat management nest site selection Saltpan restoration Shell supplementation SHOREBIRDS
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