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The potential mechanism and clinical application value of remote ischemic conditioning in stroke 被引量:1
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作者 Yajun Zhu Xiaoguo Li +6 位作者 Xingwei Lei Liuyang Tang Daochen Wen Bo Zeng Xiaofeng Zhang Zichao Huang Zongduo Guo 《Neural Regeneration Research》 SCIE CAS 2025年第6期1613-1627,共15页
Some studies have confirmed the neuroprotective effect of remote ischemic conditioning against stroke. Although numerous animal researches have shown that the neuroprotective effect of remote ischemic conditioning may... Some studies have confirmed the neuroprotective effect of remote ischemic conditioning against stroke. Although numerous animal researches have shown that the neuroprotective effect of remote ischemic conditioning may be related to neuroinflammation, cellular immunity, apoptosis, and autophagy, the exact underlying molecular mechanisms are unclear. This review summarizes the current status of different types of remote ischemic conditioning methods in animal and clinical studies and analyzes their commonalities and differences in neuroprotective mechanisms and signaling pathways. Remote ischemic conditioning has emerged as a potential therapeutic approach for improving stroke-induced brain injury owing to its simplicity, non-invasiveness, safety, and patient tolerability. Different forms of remote ischemic conditioning exhibit distinct intervention patterns, timing, and application range. Mechanistically, remote ischemic conditioning can exert neuroprotective effects by activating the Notch1/phosphatidylinositol 3-kinase/Akt signaling pathway, improving cerebral perfusion, suppressing neuroinflammation, inhibiting cell apoptosis, activating autophagy, and promoting neural regeneration. While remote ischemic conditioning has shown potential in improving stroke outcomes, its full clinical translation has not yet been achieved. 展开更多
关键词 Akt apoptosis autophagy cerebral perfusion cerebral vascular stenosis clinical transformation hemorrhagic stroke ischemic stroke NEUROINFLAMMATION neuroprotection Notch1 PI3K remote ischemic conditioning STROKE
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Characteristics of Surface Solar Radiation under Different Air Pollution Conditions over Nanjing, China: Observation and Simulation 被引量:7
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作者 Hao LUO Yong HAN +2 位作者 Chunsong LU Jun YANG Yonghua WU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2019年第10期1047-1059,共13页
Surface solar radiation (SSR) can affect climate, the hydrological cycle, plant photosynthesis, and solar power. The values of solar radiation at the surface reflect the influence of human activity on radiative climat... Surface solar radiation (SSR) can affect climate, the hydrological cycle, plant photosynthesis, and solar power. The values of solar radiation at the surface reflect the influence of human activity on radiative climate and environmental effects, so it is a key parameter in the evaluation of climate change and air pollution due to anthropogenic disturbances. This study presents the characteristics of the SSR variation in Nanjing, China, from March 2016 to June 2017, using a combined set of pyranometer and pyrheliometer observations. The SSR seasonal variation and statistical properties are investigated and characterized under different air pollution levels and visibilities. We discuss seasonal variations in visibility, air quality index (AQI), particulate matter (PM10 and PM2.5), and their correlations with SSR. The scattering of solar radiation by particulate matter varies significantly with particle size. Compared with the particulate matter with aerodynamic diameter between 2.5 μm and 10 μm (PM2.5-10), we found that the PM2.5 dominates the variation of scattered radiation due to the differences of single-scattering albedo and phase function. Because of the correlation between PM2.5 and SSR, it is an effective and direct method to estimate PM2.5 by the value of SSR, or vice versa to obtain the SSR by the value of PM2.5. Under clear-sky conditions (clearness index ≥0.5), the visibility is negatively correlated with the diffuse fraction, AQI, PM10, and PM2.5, and their correlation coefficients are ?0.50,?0.60,?0.76, and ?0.92, respectively. The results indicate the linkage between scattered radiation and air quality through the value of visibility. 展开更多
关键词 surface solar radiation air pollution PARTICULATE MATTER VISIBILITY RADIATIVE transfer
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Numerical simulation of an extreme haze pollution event over the North China Plain based on initial and boundary condition ensembles 被引量:3
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作者 LI Xiaobin LIU Hongbo +1 位作者 ZHANG Ziyin LIU Juanjuan 《Atmospheric and Oceanic Science Letters》 CSCD 2019年第6期434-443,共10页
The North China Plain often su ers heavy haze pollution events in the cold season due to the rapid industrial development and urbanization in recent decades.In the winter of 2015,the megacity cluster of Beijing Tianji... The North China Plain often su ers heavy haze pollution events in the cold season due to the rapid industrial development and urbanization in recent decades.In the winter of 2015,the megacity cluster of Beijing Tianjin Hebei experienced a seven-day extreme haze pollution episode with peak PM2.5(particulate matter(PM)with an aerodynamic diameter≤2.5μm)concentration of 727μg m 3.Considering the in uence of meteorological conditions on pollu-tant evolution,the e ects of varying initial conditions and lateral boundary conditions(LBCs)of the WRF-Chem model on PM2.5 concentration variation were investigated through ensemble methods.A control run(CTRL)and three groups of ensemble experiments(INDE,BDDE,INBDDE)were carried out based on difierent initial conditions and LBCs derived from ERA5 reanalysis data and its 10 ensemble members.The CTRL run reproduced the meteorological conditions and the overall life cycle of the haze event reasonably well,but failed to capture the intense oscillation of the instantaneous PM2.5 concentration.However,the ensemble forecasting showed a considerable advantage to some extent.Compared with the CTRL run,the root-mean-square error(RMSE)of PM2.5 concentration decreased by 4.33%,6.91%,and 8.44%in INDE,BDDE and INBDDE,respectively,and the RMSE decreases of wind direction(5.19%,8.89%and 9.61%)were the dominant reason for the improvement of PM2.5 concentration in the three ensemble experiments.Based on this case,the ensemble scheme seems an e ective method to improve the prediction skill of wind direction and PM2.5 concentration by using the WRF-Chem model. 展开更多
关键词 Haze pollution PM 2.5 WRF Chem initial and lateral boundary conditions ensemble forecasting
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A CONDITIONAL STABILITY FOR AN INVERSE PROBLEM ARISING IN GROUNDWATER POLLUTION 被引量:7
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作者 李功胜 谭永基 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2005年第3期217-225,共9页
An inverse problem of determining magnitude of groundwater pollution in a hydrologic region is investigated. By applying integral identity methods, a conditional stability for the inverse problem here is constructed w... An inverse problem of determining magnitude of groundwater pollution in a hydrologic region is investigated. By applying integral identity methods, a conditional stability for the inverse problem here is constructed with aids of an optimal adjoint problem and a suitable topology. 展开更多
关键词 地下水污染 污染源头 积分方程 条件稳定性
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Research on Characteristics of Atmospheric Pollution and Meteorological Condition in South of Northern China
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作者 Jun Zhang Xiaohui Song 《Journal of Geoscience and Environment Protection》 2017年第1期73-84,共12页
Taking Handan City (the south of Northern China) as an example, and making use of the environmentally friendly materials of Handan Environmental Monitor Station in 2013-2014, the surface observational data of Handan M... Taking Handan City (the south of Northern China) as an example, and making use of the environmentally friendly materials of Handan Environmental Monitor Station in 2013-2014, the surface observational data of Handan Meteorological Station and the sounding data of Xingtai station, combined with the integrated analysis of numerical prediction and simulation, this paper shows that, in 2014, the air quality improved;the emission-reduction effect was significant;the days of heavy pollution decreased;and the days up to the standard increased;the annual average concentration of pollutants PM2.5 and PM10 in the whole city showed a decreasing tendency compared to the same period of last year. In 2014, there were a total of 9 weather processes of heavy pollution lasting more than 3 days and the duration was significantly shorter than that in 2013, which indicated that effective emission-reduction measures significantly shortened the duration of weather processes of heavy pollution. The comprehensive analysis of meteorological conditions, such as the days of light wind, wind speed, wind frequency, PM2.5 concentration at different wind directions, the thickness and intensity of the inversion layer, and the height of the mixed layer, showed that, compared with the same period in 2013, the general meteorological conditions of air pollutant dispersion were basically flat and slightly disadvantageous in 2014. Handan municipal government increased the intensity of the prevention and control of air pollution in 2014, promulgated and adopted a series of air pollution control policies and emission-reduction control measures, and achieved some results, especially the emission-reduction measures during the APEC meeting which were obviously effective. 展开更多
关键词 HEAVY pollution AIR Quality METEOROLOGICAL conditions
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Study on Model of Indoor Air Pollution Forecast for Decoration Under Natural Ventilation Condition
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作者 YAN-FENG HONG XUN CHEN NING XU 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2005年第5期345-348,共4页
To establish the model of indoor air pollution forecast for decoration. Methods The model was based on the balance model for diffusing mass. Results The data between testing concentration and estimating concentration ... To establish the model of indoor air pollution forecast for decoration. Methods The model was based on the balance model for diffusing mass. Results The data between testing concentration and estimating concentration were compared. The maximal error was less than 30% and average error was 14.6%. Conclusion The model can easily predict whether the pollution for decoration exceeds the standard and how long the room is decorated. 展开更多
关键词 Air pollution indoor MODEL Natural ventilation
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Analysis and Countermeasure on Present Conditions of Animal Excrement Pollution in Heilongjiang Province
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作者 WANG Yang LI Cuixia 《Journal of Northeast Agricultural University(English Edition)》 CAS 2008年第3期75-79,共5页
Attaching more importance to the problem of animal excrement pollution is the premise of realizing the sustainable development of animal husbandry in Heilongjiang Province. With the constant expansion of the scale of ... Attaching more importance to the problem of animal excrement pollution is the premise of realizing the sustainable development of animal husbandry in Heilongjiang Province. With the constant expansion of the scale of breeding industry, the amount of animal excrement will increase greatly, corresponding to the increasing pressure on water and land. Therefore, for the sake of promoting the coordinated development of animal husbandry and the environment, this paper analyzed the status of animal excrement pollution in Heilongjiang Province. On this base, the paper suggested that we must control animal excrement pollution proceeding from reality by using administrative means, legal means, economic means and technical means. 展开更多
关键词 animal excrement pollution problem control measures
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Characteristics and Meteorological Conditions of Ozone Pollution in Shantou City
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作者 Juan LI Chengliu LI +6 位作者 Lianghong XIAO Yan GUO Yiyao HUANG Shuchi CHEN Miao CHEN Wenshu LI Yufeng ZHANG 《Meteorological and Environmental Research》 CAS 2021年第1期19-25,共7页
Based on routine monitoring data of air quality and meteorological data in Shantou City during 2015-2019,temporal-spatial variation characteristics of O 3 pollution and its correlation with meteorological conditions i... Based on routine monitoring data of air quality and meteorological data in Shantou City during 2015-2019,temporal-spatial variation characteristics of O 3 pollution and its correlation with meteorological conditions in Shantou City were explored.The research results showed that O 3 pollution days in Shantou City showed an increasing trend year by year,and O 3 pollution had far-distance transportation and the development trend from offshore Nan ao Island to urban district.In spring and autumn,there was serious O 3 pollution,and it was the most prominent in October.Its diurnal variation in O 3 pollution days was mainly wide-peak type in the afternoon,showing as that O 3 concentration declined slowly after the noon.In O 3 pollution days,higher O 3 concentration was easy to appear at night,causing that O 3 peak in the second day was uplifted,and there was continuous O 3 pollution.Combining backward trajectory analysis chart,it was found that Shantou was mainly affected by coastal transport of northerly polluted air mass,and it was transported into Shantou City from the east to the northeast.O 3 from long-distance transmission superimposed with locally generated O 3,which commonly pushed up the level of O 3 concentration.The weather of O 3 pollution in Shantou City had the characteristics of high temperature and low humidity.There was 25-30℃of temperature interval and 46%-60%of relative humidity interval,and it was accompanied by grade-2 easterly wind. 展开更多
关键词 Shantou City OZONE pollution characteristics Meteorological conditions
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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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Haematology of <i>Pelophylax ridibundus</i>(Amphibia: <i>Ranidae</i>) of <i>Striata</i>and <i>Maculata</i>Morphs in Populations Living in Conditions of Anthropogenic Pollution in Southern Bulgaria
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作者 Zhivko Marinov Zhelev Muhammad Arif +2 位作者 Georgi Sashev Popgeorgiev Mamoona Rauf Nikolai Hristov Mehterov 《Open Journal of Animal Sciences》 2014年第4期206-216,共11页
Basic haematological parameters were studied in adult, sexually mature individuals of colour morphs (striata and maculata) in the populations of Pelophylax ridibundus living in biotopes with various degrees of anthrop... Basic haematological parameters were studied in adult, sexually mature individuals of colour morphs (striata and maculata) in the populations of Pelophylax ridibundus living in biotopes with various degrees of anthropogenic pollution (control, domestic sewage pollution and heavy metal pollution) in Southern Bulgaria. We found that in the polluted biotopes in individuals of both morphs of P. ridibundus the blood parameters: erythrocyte (RBC) and leukocyte (WBS) count, haemoglobin concentration (Hb), haematocrit (PCV) were statistically reliably higher, the number of lymphocytes (Ly) decreased, and the parameters: mean cell haemoglobin (MCH), mean cell haemoglobin concentration (MCHC), mean cell volume (MCV) and differential blood formula changed considerably in comparison with the control group. In terms of anthropogenic pollution, the average values of RBC and Hb were higher in P. ridibundus of striata morph. 展开更多
关键词 Striata and Maculata MORPHS Pelophylax ridibundus Anthropogenic pollution Bio-Indication Haematological Parameters SOUTHERN Bulgaria
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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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Conditioned medium from human dental pulp stem cells treats spinal cord injury by inhibiting microglial pyroptosis 被引量:3
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作者 Tao Liu Ziqian Ma +8 位作者 Liang Liu Yilun Pei Qichao Wu Songjie Xu Yadong Liu Nan Ding Yun Guan Yan Zhang Xueming Chen 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第5期1105-1111,共7页
Human dental pulp stem cell transplantation has been shown to be an effective therapeutic strategy for spinal cord injury.However,whether the human dental pulp stem cell secretome can contribute to functional recovery... Human dental pulp stem cell transplantation has been shown to be an effective therapeutic strategy for spinal cord injury.However,whether the human dental pulp stem cell secretome can contribute to functional recovery after spinal cord injury remains unclear.In the present study,we established a rat model of spinal cord injury based on impact injury from a dropped weight and then intraperitoneally injected the rats with conditioned medium from human dental pulp stem cells.We found that the conditioned medium effectively promoted the recovery of sensory and motor functions in rats with spinal cord injury,decreased expression of the microglial pyroptosis markers NLRP3,GSDMD,caspase-1,and interleukin-1β,promoted axonal and myelin regeneration,and inhibited the formation of glial scars.In addition,in a lipopolysaccharide-induced BV2 microglia model,conditioned medium from human dental pulp stem cells protected cells from pyroptosis by inhibiting the NLRP3/caspase-1/interleukin-1βpathway.These results indicate that conditioned medium from human dental pulp stem cells can reduce microglial pyroptosis by inhibiting the NLRP3/caspase-1/interleukin-1βpathway,thereby promoting the recovery of neurological function after spinal cord injury.Therefore,conditioned medium from human dental pulp stem cells may become an alternative therapy for spinal cord injury. 展开更多
关键词 BV2 conditioned medium dental pulp stem cells GSDMD MICROGLIA NEUROINFLAMMATION NLRP3 PYROPTOSIS spinal cord injury
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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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Uncertainties of landslide susceptibility prediction: Influences of random errors in landslide conditioning factors and errors reduction by low pass filter method 被引量:2
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作者 Faming Huang Zuokui Teng +4 位作者 Chi Yao Shui-Hua Jiang Filippo Catani Wei Chen Jinsong Huang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期213-230,共18页
In the existing landslide susceptibility prediction(LSP)models,the influences of random errors in landslide conditioning factors on LSP are not considered,instead the original conditioning factors are directly taken a... In the existing landslide susceptibility prediction(LSP)models,the influences of random errors in landslide conditioning factors on LSP are not considered,instead the original conditioning factors are directly taken as the model inputs,which brings uncertainties to LSP results.This study aims to reveal the influence rules of the different proportional random errors in conditioning factors on the LSP un-certainties,and further explore a method which can effectively reduce the random errors in conditioning factors.The original conditioning factors are firstly used to construct original factors-based LSP models,and then different random errors of 5%,10%,15% and 20%are added to these original factors for con-structing relevant errors-based LSP models.Secondly,low-pass filter-based LSP models are constructed by eliminating the random errors using low-pass filter method.Thirdly,the Ruijin County of China with 370 landslides and 16 conditioning factors are used as study case.Three typical machine learning models,i.e.multilayer perceptron(MLP),support vector machine(SVM)and random forest(RF),are selected as LSP models.Finally,the LSP uncertainties are discussed and results show that:(1)The low-pass filter can effectively reduce the random errors in conditioning factors to decrease the LSP uncertainties.(2)With the proportions of random errors increasing from 5%to 20%,the LSP uncertainty increases continuously.(3)The original factors-based models are feasible for LSP in the absence of more accurate conditioning factors.(4)The influence degrees of two uncertainty issues,machine learning models and different proportions of random errors,on the LSP modeling are large and basically the same.(5)The Shapley values effectively explain the internal mechanism of machine learning model predicting landslide sus-ceptibility.In conclusion,greater proportion of random errors in conditioning factors results in higher LSP uncertainty,and low-pass filter can effectively reduce these random errors. 展开更多
关键词 Landslide susceptibility prediction conditioning factor errors Low-pass filter method Machine learning models Interpretability analysis
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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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Mixed D-vine copula-based conditional quantile model for stochastic monthly streamflow simulation 被引量:2
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作者 Wen-zhuo Wang Zeng-chuan Dong +3 位作者 Tian-yan Zhang Li Ren Lian-qing Xue Teng Wu 《Water Science and Engineering》 EI CAS CSCD 2024年第1期13-20,共8页
Copula functions have been widely used in stochastic simulation and prediction of streamflow.However,existing models are usually limited to single two-dimensional or three-dimensional copulas with the same bivariate b... Copula functions have been widely used in stochastic simulation and prediction of streamflow.However,existing models are usually limited to single two-dimensional or three-dimensional copulas with the same bivariate block for all months.To address this limitation,this study developed a mixed D-vine copula-based conditional quantile model that can capture temporal correlations.This model can generate streamflow by selecting different historical streamflow variables as the conditions for different months and by exploiting the conditional quantile functions of streamflows in different months with mixed D-vine copulas.The up-to-down sequential method,which couples the maximum weight approach with the Akaike information criteria and the maximum likelihood approach,was used to determine the structures of multivariate Dvine copulas.The developed model was used in a case study to synthesize the monthly streamflow at the Tangnaihai hydrological station,the inflow control station of the Longyangxia Reservoir in the Yellow River Basin.The results showed that the developed model outperformed the commonly used bivariate copula model in terms of the performance in simulating the seasonality and interannual variability of streamflow.This model provides useful information for water-related natural hazard risk assessment and integrated water resources management and utilization. 展开更多
关键词 Stochastic monthly streamflow simulation Mixed D-vine copula conditional quantile model Up-to-down sequential method Tangnaihai hydrological station
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Index of Atmospheric Purity reflects the ecological conditions better than the environmental pollution in the Carpathian forests
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作者 Magdalena TANONA Pawel CZARNOTA 《Journal of Mountain Science》 SCIE CSCD 2020年第11期2691-2706,共16页
The Index of Atmospheric Purity(IAP)is a popular tool used for the assessment of air quality in polluted urban areas,on the basis of phytosociological data of epiphytic lichen communities.We hypothesized that this ind... The Index of Atmospheric Purity(IAP)is a popular tool used for the assessment of air quality in polluted urban areas,on the basis of phytosociological data of epiphytic lichen communities.We hypothesized that this indicator could also be used in less polluted forest areas to determine the quality of ecological conditions for lichens.The aim of the present study was to verify the use of IAP method in the assessment of environmental pollution,and alternatively for the assessment of general ecological conditions in protected mountain forests of Gorce National Park(Polish Western Carpathians)based on the epiphytic lichen biota associated with Picea abies.The spatial distribution of IAP values on monitored sites in GNP was compared with:1)spatial distribution of accumulated sulfur,nitrogen,selected heavy metals,and total heavy metals in Hypogymnia physodes thalli in 1993 and 2018(30 sites),2)mean ecological indicator values characterizing species requirements for light(L),substrate reaction(R)and nutrients(N),in 1993,2013 and 2018(33 sites).Generalized linear model and redundancy analysis were performed for disclosing most influencing factors affecting lichen communities.The study revealed a few negligible relationships between IAP values and accumulation of such elements as Ni,Mn,Cd,and Cr in both monitoring periods.Simultaneously,IAP can be useful for the identification of forest areas with a high degree of naturalness. 展开更多
关键词 BIOMONITORING LICHENS Forest ecology Norway spruce Ecological indices Environmental pollution
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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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Genesis of LCT Pegmatites during Early Paleozoic Orogeny of the North Qinling Orogenic Belt,China:Emplacement Conditions and Structural Control 被引量:1
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作者 CEN Jubiao FENG Yonggang +6 位作者 LIANG Ting WANG Mengxi ZHANG Jianxin TAN Xijuan ZHANG Jie GAO Jinggang HE Lei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第5期1226-1243,共18页
The Guanpo pegmatite field in the North Qinling orogenic belt(NQB),China,hosts the most abundant LCT pegmatites.However,their emplacement conditions and structural control remain unexplored.In this contribution,we inv... The Guanpo pegmatite field in the North Qinling orogenic belt(NQB),China,hosts the most abundant LCT pegmatites.However,their emplacement conditions and structural control remain unexplored.In this contribution,we investigated it combining pegmatite orientation measurement with oxygen isotope geothermometry and fluid inclusion study.The orientations of type A1 pegmatites(P_(f)<σ_(2))are predominantly influenced by P-and T-fractures due to simple shearing in Shiziping dextral thrust shear zone during D_(2)deformation,whereas type A2 pegmatites(contemporaneous with D_(4))are governed by hydraulic fractures aligned with S_(0)and S_(0+1)stemming from fluid pressure(P_(f)<σ_(2)).Additionally,type B pegmatites(P_(f)≤σ_(2))exhibit orientations shaped by en echelon extensional fractures in local ductile shear zones(contemporaneous with D_(3)).The albite-quartz oxygen isotope geothermometry and microthermometric analysis of fluid inclusions in elbaites from the latest pegmatites(including types B and A2)suggest that the crystallization P-T for late magmatic and hydrothermal stages are 527.5-559.2℃,320℃,3.1-3.6 kbar and 2.0 kbar,respectively.Our observations along with previous studies suggest that the genesis of the LCT pegmatites was a long-term,multi-stage event during early Paleozoic orogeny(including the collision stage)of the NQB,and was facilitated by various local fractures. 展开更多
关键词 LCT pegmatite emplacement mechanism emplacement condition oxygen isotope geothermometry fluid inclusion North Qinling orogenic belt
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