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Intervention effect and mechanism of Compound Herba Gueldenstaedtiae in a mouse model of breast hyperplasia
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作者 Wu Yilin Tian Hongying +8 位作者 Sun Jiale Jiao Jiajia Zhao Zihan Shao Jinhuan Zhao Kaiyue Zhou Min Li Qian Li Zexin Yue Changwu 《中国组织工程研究》 北大核心 2026年第17期4377-4389,共13页
BACKGROUND:Breast hyperplasia is a common benign breast disease mainly caused by endocrine disorders,manifested as abnormal hyperplasia of breast tissue.In recent years,traditional Chinese medicine compounds and probi... BACKGROUND:Breast hyperplasia is a common benign breast disease mainly caused by endocrine disorders,manifested as abnormal hyperplasia of breast tissue.In recent years,traditional Chinese medicine compounds and probiotics have shown good potential in regulating the endocrine system and improving the intestinal microecology,providing new ideas for the treatment of breast hyperplasia.OBJECTIVE:To explore the effects and mechanisms of traditional Chinese medicine compounds and fermented probiotic compounds on breast hyperplasia in mice,providing new theoretical and experimental bases for the clinical treatment and prevention of breast hyperplasia.METHODS:(1)Network pharmacology tools were used to predict the anti-breast-hyperplasia activity of Herba Gueldenstaedtiae(Euphorbia humifusa),as well as its potential targets and signaling pathways.The databases included:TCMSP,OMIM,GeneCards database,UniProt website,Venny2.1.0 website,Metascape,HERB website,and STRING database,all of which are open-access databases.Network pharmacology can predict and screen key information such as the targets corresponding to the active ingredients of traditional Chinese medicine,disease targets,and action pathways through network analysis and computer-system analysis.Therefore,it has been increasingly widely used in the research of traditional Chinese medicine.(2)A breast hyperplasia model was induced in mice by injecting estrogen and progesterone.Mice in the normal blank group were injected intraperitoneally with normal saline every day.Mice in the model group and drugadministration groups were injected intraperitoneally with estradiol benzoate injection at a concentration of 0.5 mg/kg every day for 25 days.From the 26th day,the injection of estradiol benzoate injection was stopped.Mice in the normal blank group were injected intramuscularly with normal saline every day,and mice in the model group and drug-administration groups were injected intramuscularly with progesterone injection at a concentration of 5 mg/kg for 5 days.After the model was established,each group was given drugs respectively.The normal blank group and the model group were gavaged with 0.2 mL/d of normal saline;the positive blank group(Xiaozheng Pill group)was gavaged with an aqueous solution of Xiaozheng Pill at 0.9 mg/g;the low-,medium-and high-dose groups of Compound Herba Gueldenstaedtiae were gavaged with an aqueous solution of the compound medicine at 0.75,1.5,and 3.0 mg/(g·d)respectively;the low-,medium-and high-dose groups of traditional Chinese medicine-bacteria fermentation were gavaged with an aqueous solution of the compound medicine at 0.75,1.5,and 3.0 mg/(g·d)respectively.The administration was continuous for 30 days.RESULTS AND CONCLUSION:(1)The results of network pharmacology research showed that the Compound Herba Gueldenstaedtiae(Euphorbia humifusa)contained 46 active ingredients,which were related to 1213 potential targets.After comparison with 588 known breast-hyperplasia targets,it was speculated that 50 of these targets might be related to the direct effect of the compound on breast hyperplasia.(2)After drug intervention,there was no significant change in the high-dose group of Compound Herba Gueldenstaedtiae compared with the normal blank group.The liver indicators of the other intervention groups all significantly decreased(P<0.05).(3)In terms of kidney and uterine indicators,the medium-dose group of Compound Herba Gueldenstaedtiae decreased significantly compared with the normal blank group(P<0.05).In terms of the uterine index,the model group increased significantly compared with the normal blank group(P<0.01).(4)After 1-month drug treatment,the number of lobules and acini in the breast tissue of the Xiaozheng Pill group,the low,medium,and high-dose group of Compound Herba Gueldenstaedtiae,the low,medium,and highdose groups of traditional Chinese medicine-bacteria fermentation decreased,and the duct openings narrowed.With the increase of drug dose,diffuse hyperplasia of breast tissue was significantly improved.(5)The ELISA results showed that compared with the model group,the estrogen level was lower in the medium-dose group of traditional Chinese medicine-bacteria fermentation after the intervention(P<0.05).In addition,the follicle-stimulating hormone level in the low-dose group of Compound Herba Gueldenstaedtiae was lower than that of the model group(P<0.05).(6)The intervention in the mouse model led to changes in the abundance of short chain fatty acids and intestinal flora in all groups.To conclude,the Compound Herba Gueldenstaedtiae and its probiotic fermentation products significantly improved mammary gland hyperplasia in mice by regulating hormone levels,improving the structure of the gut microbiota,and increasing the content of shortchain fatty acids,providing new ideas and potential sources of drugs for the treatment of breast hyperplasia. 展开更多
关键词 Herba Gueldenstaedtiae traditional Chinese medicine compound mice with breast hyperplasia microbial fermentation gut microbiota network pharmacology short-chain fatty acids hormone levels inflammatory response endocrine disorders
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Impacts of 1.5℃ and 2.0℃ Global Warming on the Onset,Cessation,and Length of the Rainy Season in Global Land Monsoon Regions
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作者 Thierry N.TAGUELA Ibraheem RAJI +4 位作者 Akintomide A.AKINSANOLA Priyanshi SINGHAI Oluwafemi E.ADEYERI Caroline M.WAINWRIGHT Rondrotiana BARIMALALA 《Advances in Atmospheric Sciences》 2026年第1期87-102,共16页
The onset,cessation,and length of the rainy season are crucial for global water resources,agricultural practices,and food security.However,the response of precipitation seasonality to global warming remains uncertain.... The onset,cessation,and length of the rainy season are crucial for global water resources,agricultural practices,and food security.However,the response of precipitation seasonality to global warming remains uncertain.In this study,we analyze how global warming levels(GWLs)of 1.5℃ and 2℃ could affect the timing of rainfall onset(RODs),rainfall cessation(RCDs),and the overall duration of the rainy season(LRS)over global land monsoon(GLM)regions using simulations from CMIP6 under the SSP2-4.5 and SSP5-8.5 scenarios.With high model consensus,our results reveal that RODs are projected to occur later over Southern Africa,North Africa,and South America,but earlier over South Asia and Australia,in a warmer climate.The projected early RODs in Australia are more pronounced at the 2℃ GWL under SSP5-8.5.On the other hand,early RCDs are projected over South America and East Asia,while late RCDs are projected over North Africa,with high inter-model agreement.These changes are associated with a future decrease in LRS in most GLM regions.Additionally,we found that continuous warming over 1.5℃ will further reduce the length of the rainy season,especially over the South America,North Africa,and Southern Africa monsoon regions.The findings underscore the urgent need to mitigate global warming. 展开更多
关键词 rainfall onset rainfall cessation global land monsoon rainy season length CMIP6 projections global warming levels
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Early Opportunities for Onshore and Offshore CCUS Deployment in the Chinese Cement Industry 被引量:4
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作者 Jing-Li Fan Yifan Mao +1 位作者 Kai Li Xian Zhang 《Engineering》 2025年第3期348-362,共15页
The promotion of deep decarbonization in the cement industry is crucial for mitigating global climate change,a key component of which is carbon capture,utilization,and storage(CCUS)technology.Despite its importance,th... The promotion of deep decarbonization in the cement industry is crucial for mitigating global climate change,a key component of which is carbon capture,utilization,and storage(CCUS)technology.Despite its importance,there is a lack of empirical assessments of early opportunities for CCUS implementation in the cement sector.In this study,a comprehensive onshore and offshore source–sink matching optimization assessment framework for CCUS retrofitting in the cement industry,called the SSM-Cement framework,is proposed.The framework comprises four main modules:the cement plant suitability screening module,the storage site assessment module,the source–sink matching optimization model module,and the economic assessment module.By applying this framework to China,919 candidates are initially screened from 1132 existing cement plants.Further,603 CCUS-ready cement plants are identified,and are found to achieve a cumulative emission reduction of 18.5 Gt CO_(2) from 2030 to 2060 by meeting the CCUS feasibility conditions for constructing both onshore and offshore CO_(2) transportation routes.The levelized cost of cement(LCOC)is found to range from 30 to 96(mean 73)USD·(t cement)^(-1),while the levelized carbon avoidance cost(LCAC)ranges from^(-5) to 140(mean 88)USD·(t CO_(2))^(-1).The northeastern and northwestern regions of China are considered priority areas for CCUS implementation,with the LCAC concentrated in the range of 35 to 70 USD·(t CO_(2))^(-1).In addition to onshore storage of 15.8 Gt CO_(2) from 2030 to 2060,offshore storage would contribute 2.7 Gt of decarbonization for coastal cement plants,with comparable LCACs around 90 USD·(t CO_(2))^(-1). 展开更多
关键词 Cement industry Carbon capture utilization and storage levelized cost of cement Source-sink matching Offshore storage continental shale oil
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基于高解析度CFD-DEM流固耦合算法的滑坡涌浪数值计算模型
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作者 赵兰浩 李荣臻 +1 位作者 毛佳 肖景文 《华北水利水电大学学报(自然科学版)》 北大核心 2025年第6期92-100,共9页
【目的】库岸滑坡涌浪严重威胁库区安全,现有经验公式及传统数值模型难以准确刻画涌浪产生过程中的流体-固体耦合效应。旨在建立一种基于高解析度CFD-DEM流固耦合算法的数值模型,以精确模拟滑坡涌浪全过程。【方法】采用基于欧拉框架的... 【目的】库岸滑坡涌浪严重威胁库区安全,现有经验公式及传统数值模型难以准确刻画涌浪产生过程中的流体-固体耦合效应。旨在建立一种基于高解析度CFD-DEM流固耦合算法的数值模型,以精确模拟滑坡涌浪全过程。【方法】采用基于欧拉框架的计算流体动力学(CFD)模拟流体运动,基于拉格朗日框架的离散元法(DEM)描述滑坡体运动,通过浸入边界法(IBM)处理移动边界与强流固耦合作用,并利用守恒式Level Set方法(CLS)追踪自由界面演变。通过交错迭代实现流体与固体间的高解析度耦合求解。【结果】(1)双颗粒沉降算例验证表明,模型能精确捕捉颗粒尾流效应及“牵引-接触-翻滚”现象,计算结果与文献结果高度吻合。(2)可变形水下滑坡涌浪模拟显示,模型可准确反映稠密块体与流体的相互作用,自由面演化规律与试验数据一致。(3)在Lituya湾实际案例中,模型成功复现了涌浪产生、传播及爬高过程,最大浪高计算值(146 m)与实测值(150 m)误差仅为2.7%。【结论】所提出的高解析度CFD-DEM耦合模型能有效模拟滑坡涌浪中的复杂流固耦合行为,显著优于依赖经验公式的非解析方法,为库区滑坡涌浪灾害风险评估提供了可靠的数值工具。 展开更多
关键词 滑坡涌浪 浸入边界法 计算流体力学 离散元法 守恒式Level Set方法
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A review of photovoltaic/thermal(PV/T)incorporation in the hydrogen production process
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作者 Hussein A.Kazem Miqdam T.Chaichan +4 位作者 Ali H.A.Al-Waeli K.Sopian Waheeb E.Alnaser Lawrence Kazmerski Naser W.Alnaser 《Global Energy Interconnection》 2025年第3期363-393,共31页
Integrating the photovoltaic/thermal(PV/T)system in green hydrogen production is an improvement in sustainable energy technologies.In PV/T systems,solar energy is converted into electricity and thermal energy simultan... Integrating the photovoltaic/thermal(PV/T)system in green hydrogen production is an improvement in sustainable energy technologies.In PV/T systems,solar energy is converted into electricity and thermal energy simultaneously using hot water or air together with electricity.This dual use saves a significant amount of energy and officially fights greenhouse gases.Different cooling techniques have been proposed in the literature for improving the overall performance of the PV/T systems;employing different types of agents including nanofluids and phase change materials.Hydrogen is the lightest and most abundant element in the universe and has later turned into a flexible energy carrier for transportation and other industrial applications.Issues,including the processes of Hydrogen manufacturing,preservation as well as some risks act as barriers.This paper provides an analysis of several recent publications on the efficiency of using PV/T technology in the process of green hydrogen production and indicates the potential for its increased efficiency as compared to conventional systems that rely on fossil fuels.Due to the effective integration of solar energy,the PV/T system can play an important role in the reduction of the levelized cost of hydrogen(LCOH)and hence play an important part in reducing the economic calculations of the decarbonized energy system. 展开更多
关键词 PV/T Green hydrogen PRODUCTION Liquification Technology readiness levels levelized cost of hydrogen
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Techno-Economic Potential Evaluation of Small-Scale off-Grid Renewable Power Systems in Xinjiang,China
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作者 PU Xiaohua GU Wenbo 《新疆大学学报(自然科学版中英文)》 2025年第2期168-185,共18页
A hybrid energy system is built for the power demand of a community in Xinjiang of China,and pumped storage and lithium batteries are used as energy storage devices.The feasibility of different configurations is evalu... A hybrid energy system is built for the power demand of a community in Xinjiang of China,and pumped storage and lithium batteries are used as energy storage devices.The feasibility of different configurations is evaluated through technoeconomic analysis.Technical-economic parameters are set in the HOMER Pro software to obtain optimal configuration and techno-economic evaluation and sensitivity analysis.The study also explores the impact of different types of PV tracking systems and module costs on system performance.The results show that the lowest levelized cost of energy(LCOE)(0.135$/kWh)can be achieved with pumped hydro,which is more economical than lithium batteries.PV tracking systems can improve solar efficiency.Compared with diesel systems,renewable energy has economic advantages and environmental benefits.In most regions of Xinjiang,solar energy is more competitive than wind power.In areas with abundant wind resources,the integration of wind and solar energy can reduce costs. 展开更多
关键词 net present cost levelized cost of energy renewable energy system capacity sizing
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Cost Effectivities Analysis of Perovskite Solar Cells:Will it Outperform Crystalline Silicon Ones?
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作者 Yingming Liu Ziyang Zhang +7 位作者 Tianhao Wu Wenxiang Xiang Zhenzhen Qin Xiangqian Shen Yong Peng Wenzhong Shen Yongfang Li Liyuan Han 《Nano-Micro Letters》 2025年第9期337-347,共11页
The commercialization of perovskite solar cells(PSCs)has garnered worldwide attention and many efforts were devoted on the improvement of efficiency and stability.Here,we estimated the cost effectivities of PSCs based... The commercialization of perovskite solar cells(PSCs)has garnered worldwide attention and many efforts were devoted on the improvement of efficiency and stability.Here,we estimated the cost effectivities of PSCs based on the current industrial condition.Through the analysis of current process,the manufacturing cost and the levelized cost of electricity(LCOE)of PSCs is estimated as 0.57$W^(−1) and 18-22 US cents(kWh)^(−1),respectively,and we demonstrate the materials cost shares 70%of the total cost.Sensitivity analysis indicates that the improvement of efficiency,yield and decrease in materials cost significantly reduce the cost of the modules.Analysis of the module cost and LCOE indicates that the PSCs have the potential to outperform the silicon solar cells in the condition of over 25%efficiency and 25-year lifetime in future.To achieve this target,it is essential to further refine the fabrication processes of each layer in the module,develop stable inorganic transport materials,and precisely control material formation and processing at the microscale and nanoscale to enhance charge transport. 展开更多
关键词 PEROVSKITE Manufacturing cost levelized cost of electricity
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Unlocking the potentials of depleted gas fields:A numerical evaluation of underground CO_(2) storage and geothermal energy harvesting
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作者 Amrou Al-Alawi Mingjie Chen +4 位作者 El Hadi Mazouz Tartil Al-Abri Usman Taura Mohammad Reza Nikoo Ali Al-Maktoumi 《Energy Geoscience》 2025年第2期263-277,共15页
Using partial underground CO_(2) storage as a working agent to harvest geothermal energy is a promising carbon capture,utilization,and storage(CCUS)method.It is particularly economically feasible to use or retrofit th... Using partial underground CO_(2) storage as a working agent to harvest geothermal energy is a promising carbon capture,utilization,and storage(CCUS)method.It is particularly economically feasible to use or retrofit the existing infrastructure of a hydrocarbon field.Although technical advantages of integrated CO_(2) sequestration and CO_(2)-circulated geothermal harvest using depleted hydrocarbon reservoirs have been reported,quantitative evaluations of economic benefits using existing wells of realistic reservoirs are rare.In this study,a 3-D hydrothermal flow model is built for the Triassic Argilo-Gre seux Supe rieur(TAGS)Formation of the Toual gas field,Algeria using Schlumberger Petrel and CMG-STARS software.A three-phase operational scheme is proposed for sequential CO_(2) sequestration and CO_(2)-circulated geothermal extraction over 100 years.The first phase is injecting CO_(2) for 30 years,followed by concurrent cold CO_(2) injection and hot CO_(2) extraction in the developed CO_(2) plume(circulation)for 40 years as the second phase.In the third phase,producing wells in the second phase are converted to injection wells while outer wells start to extract hot CO_(2) for another 30 years.Scenario 1 is simulated using the selected nine existing wells of the field,while an optimized Scenario 2 is designed and simulated by adding seven newly drilled wells in addition to the existing wells.Scenario 3 shares the same numerical simulation of Scenario 1,but assumes the selected nine existing wells are newly drilled for the economic evaluation.Levelized Cost of Energy(LCOE),Net Present Value(NPV),and Return on Investment(ROI)are used as economic indicators.The results demonstrate that Scenario 2,which combines the use of existing and newly drilled wells,yields improved economic metrics compared to Scenario 1:0.97 USD/MWh vs.1.54 USD/MWh for LCOE and$2.9M vs.$1.1M for NPV.Both scenarios represent profitable endeavors,with ROI values of 1.3%and 1.5%,respectively.In contrast,Scenario 3 represents the worst-case scenario,with the highest LCOE at 2.90 USD/MWh and the lowest NPV and ROI at-$0.4M and-0.2%,respectively.The negative NPV and ROI in Scenario 3 indicates that CO_(2)-circulated geothermal harvesting in aquifers or giant depleted hydrocarbon fields,without leveraging existing infrastructure,is economically infeasible. 展开更多
关键词 Depleted gas field CO_(2)geological storage Geothermal harvest levelized cost of energy(LCOE) Net present value(NPV)
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基于Level Set方法的HG-80钢晶粒长大模型的建模与仿真
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作者 刘铭阳 陈学文 +5 位作者 周正 毛怡然 徐栋栋 李强 易浩 周旭东 《材料热处理学报》 北大核心 2025年第6期162-170,共9页
为了准确预测HG-80钢的晶粒长大过程并调控其微观组织,在900~1200℃的保温温度和10~1200s的保温时间条件下,采用Gleeble-1500D型热模拟机对其进行等温保温实验,分析其晶粒长大过程,并基于实验数据建立了Burke-Turnbull晶粒长大动力学模... 为了准确预测HG-80钢的晶粒长大过程并调控其微观组织,在900~1200℃的保温温度和10~1200s的保温时间条件下,采用Gleeble-1500D型热模拟机对其进行等温保温实验,分析其晶粒长大过程,并基于实验数据建立了Burke-Turnbull晶粒长大动力学模型。通过二次开发将计算所得的Burke-Turnbull模型参数导入DIGIMU■软件中,从晶粒尺寸分布、晶粒生长动力学和晶粒拓扑结构等方面,基于Level Set方法建立了描述HG-80钢的晶粒长大模型并通过DIGIMU■软件进行仿真计算。结果表明:随着保温时间的增加,实验钢的晶粒尺寸明显增大,晶粒生长速率逐渐减小,呈抛物线状增长;为了验证Burke-Turnbull模型的准确性,将平均晶粒尺寸的模型预测值与实验值进行对比,相关系数R为0.991,表明该模型的准确性较高;通过Level Set方法仿真计算得出的晶粒形貌与实验结果吻合良好,证明该模型能有效预测不同热处理条件下HG-80钢的晶粒长大过程。 展开更多
关键词 HG-80钢 Level Set方法 晶粒长大 Burke-Turnbull模型
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The Electric Vehicle Surge:Effective Solutions for Charging Challenges with Advanced Converter Technologies 被引量:1
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作者 Rajanand Patnaik Narasipuram Md M.Pasha +1 位作者 Saleha Tabassum Amit Singh Tandon 《Energy Engineering》 2025年第2期431-469,共39页
The global adoption of Electric Vehicles(EVs)is on the rise due to their advanced features,with projections indicating they will soon dominate the private vehicle market.However,improper management of EV charging can ... The global adoption of Electric Vehicles(EVs)is on the rise due to their advanced features,with projections indicating they will soon dominate the private vehicle market.However,improper management of EV charging can lead to significant issues.This paper reviews the development of high-power,reliable charging solutions by examining the converter topologies used in rectifiers and converters that transfer electricity from the grid to EV batteries.It covers technical details,ongoing developments,and challenges related to these topologies and control strategies.The integration of rapid charging stations has introduced various Power Quality(PQ)issues,such as voltage fluctuations,harmonic distortion,and supra-harmonics,which are discussed in detail.The paper also highlights the benefits of controlled EV charging and discharging,including voltage and frequency regulation,reactive power compensation,and improved power quality.Efficient energy management and control strategies are crucial for optimizing EV battery charging within microgrids to meet increasing demand.Charging stations must adhere to specific converter topologies,control strategies,and industry standards to function correctly.The paper explores microgrid architectures and control strategies that integrate EVs,energy storage units(ESUs),and Renewable Energy Sources(RES)to enhance performance at charging points.It emphasizes the importance of various RES-connected architectures and the latest power converter topologies.Additionally,the paper provides a comparative analysis of microgrid-based charging station architectures,focusing on energy management,control strategies,and charging converter controls.The goal is to offer insights into future research directions in EV charging systems,including architectural considerations,control factors,and their respective advantages and disadvantages. 展开更多
关键词 Electric vehicles CONVERTERS RECTIFIERS power and voltage levels efficiency supra-harmonics
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Effects of water level variations on the water quality of Huayang Lakes,China 被引量:1
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作者 AN Lesheng LIU Chun +3 位作者 FAN Zhongya LIAO Kaihua WANG Wencai WANG Nan 《Journal of Geographical Sciences》 2025年第1期173-188,共16页
To explore water level variations and their dynamic influence on the water quality of Huayang Lakes,the water level from 1967 to 2023 and water quality from 2015 to 2023 were analyzed using the Mann–Kendall trend tes... To explore water level variations and their dynamic influence on the water quality of Huayang Lakes,the water level from 1967 to 2023 and water quality from 2015 to 2023 were analyzed using the Mann–Kendall trend test,box plots,and violin plots.The results show a notable hydrological rhythm of water level alternation between dry and flood seasons in Huayang Lakes,with an average water level of 12.82 m and a monthly range of 11.21–17.24m.Since 2017,the water level of Huayang Rivers has shown a decreasing trend of–0.02 m/a.Total phosphorus(TP)has become the primary pollutant.The TP concentrations in Longgan Lake(the largest lake)during the dry,rising,flood,and retreating seasons from 2015 to 2023were 0.083,0.061,0.050,and 0.059 mg/L,respectively.The effect of water level on TP was mainly observed during the low-water period.When the water level in the dry season rose to 12.25 and 13.00 m,the percentage of TP exceeding 0.1 mg/L in Longgan Lake decreased to 55.8%and 33.3%,respectively.During the dry season,wind and wave disturbances caused the release of endogenous phosphorus in Huayang Lakes.This led to drastic fluctuations in TP concentration,reducing the correlation between water level and TP.When external control is limited,the water level during the dry season should be maintained between 12.25 and 13.0 m.Additionally,it is necessary to accelerate the restoration of submerged macrophyte species(such as Hydrilla verticillata and Vallisneria natans)in the Huayang Rivers. 展开更多
关键词 shallow lake water level water quality total phosphorus Huayang Lakes
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Smoke and NO_(x)emission characteristics of in-use construction machinery base on substantial field measurement:A case study in Beijing,China 被引量:1
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作者 Huawei Yi Yangyang Cui +7 位作者 Lijun Zhu Yan Shen Han Li Guanghan Huang Linzhen Qu Dongdong Guo Lei Nie Yifeng Xue 《Journal of Environmental Sciences》 2025年第3期386-393,共8页
To understand the smoke level and NO_(x)emission characteristics of in-use construction machinery in Beijing,we selected 905 construction machines in Beijing from August 2022 to April 2023 to monitor the emission leve... To understand the smoke level and NO_(x)emission characteristics of in-use construction machinery in Beijing,we selected 905 construction machines in Beijing from August 2022 to April 2023 to monitor the emission level of smoke and NO_(x).The exhaust smoke level and excessive emission situation of different machinery types were identified,and their NO_(x)emission levels were monitored according to the free acceleration method.We investigated the correlation of NO_(x)and smoke emission,and proposed suggestions for controlling pollution discharge from construction machinery in the future.The results show that the exhaust smoke level was 0–2.62 m^(−1),followed a log-normal distribution(μ=-1.73,δ=1.09,R^(2)=0.99),with a 5.64%exceedance rate.Differenceswere observed amongmachinery types,with low-power engine forklifts showing higher smoke levels.The NO_(x)emission range was 71–1516 ppm,followed a normal distribution(μ=565.54,δ=309.51,R^(2)=0.83).Differences among machinery types were relatively small.Engine rated net power had the most significant impact on NO_(x)emissions.Thus,NO_(x)emissions from construction machinery need further attention.Furthermore,we found a weak negative correlation(p<0.05)between the emission level of smoke and NO_(x),that is the synergic emission reduction effect is poor,emphasizing the need for NO_(x)emission limits.In the future,the oversight in Beijing should prioritize phasing out ChinaⅠand ChinaⅡmachinery,and monitor emissions from highpower engine ChinaⅢmachinery. 展开更多
关键词 Fuel-oil construction machinery SMOKE NO_(x) Emission level Regulatory suggestion
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Enhanced electrode-level diagnostics for lithium-ion battery degradation using physics-informed neural networks 被引量:1
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作者 Rui Xiong Yinghao He +2 位作者 Yue Sun Yanbo Jia Weixiang Shen 《Journal of Energy Chemistry》 2025年第5期618-627,共10页
For the diagnostics and health management of lithium-ion batteries,numerous models have been developed to understand their degradation characteristics.These models typically fall into two categories:data-driven models... For the diagnostics and health management of lithium-ion batteries,numerous models have been developed to understand their degradation characteristics.These models typically fall into two categories:data-driven models and physical models,each offering unique advantages but also facing limitations.Physics-informed neural networks(PINNs)provide a robust framework to integrate data-driven models with physical principles,ensuring consistency with underlying physics while enabling generalization across diverse operational conditions.This study introduces a PINN-based approach to reconstruct open circuit voltage(OCV)curves and estimate key ageing parameters at both the cell and electrode levels.These parameters include available capacity,electrode capacities,and lithium inventory capacity.The proposed method integrates OCV reconstruction models as functional components into convolutional neural networks(CNNs)and is validated using a public dataset.The results reveal that the estimated ageing parameters closely align with those obtained through offline OCV tests,with errors in reconstructed OCV curves remaining within 15 mV.This demonstrates the ability of the method to deliver fast and accurate degradation diagnostics at the electrode level,advancing the potential for precise and efficient battery health management. 展开更多
关键词 Lithium-ion batteries Electrode level Ageing diagnosis Physics-informed neural network Convolutional neural networks
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Low-profile,low sidelobe array antenna with ultrawide beam coverage for UAV communication 被引量:1
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作者 Mei LI Zhiliang SHANG +2 位作者 Lin PU Ming-Chun TANG Lei ZHU 《Chinese Journal of Aeronautics》 2025年第1期444-454,共11页
This paper presents a design method to implement an antenna array characterized by ultra-wide beam coverage,low profile,and low Sidelobe Level(SLL)for the application of Unmanned Aerial Vehicle(UAV)air-to-ground commu... This paper presents a design method to implement an antenna array characterized by ultra-wide beam coverage,low profile,and low Sidelobe Level(SLL)for the application of Unmanned Aerial Vehicle(UAV)air-to-ground communication.The array consists of ten broadside-radiating,ultrawide-beamwidth elements that are cascaded by a central-symmetry series-fed network with tapered currents following Dolph-Chebyshev distribution to provide low SLL.First,an innovative design of end-fire Huygens source antenna that is compatible with metal ground is presented.A low-profile,half-mode Microstrip Patch Antenna(MPA)is utilized to serve as the magnetic dipole and a monopole is utilized to serves as the electric dipole,constructing the compact,end-fire,grounded Huygens source antenna.Then,two opposite-oriented end-fire Huygens source antennas are seamlessly integrated into a single antenna element in the form of monopole-loaded MPA to accomplish the ultrawide,broadside-radiating beam.Particular consideration has been applied into the design of series-fed network as well as antenna element to compensate the adverse coupling effects between elements on the radiation performance.Experiment indicates an ultrawide Half-Power Beamwidth(HPBW)of 161°and a low SLL of-25 dB with a high gain of 12 d Bi under a single-layer configuration.The concurrent ultrawide beamwidth and low SLL make it particularly attractive for applications of UAV air-to-ground communication. 展开更多
关键词 Array antenna Broad beam Fan beam Low sidelobe level Chebyshev synthesis UAV communication
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Recent advances in interfacial engineering for high-efficiency perovskite photovoltaics 被引量:1
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作者 Zhijie Wang Cheng Gong +4 位作者 Cong Zhang Chenxu Zhao Tzu-Sen Su Haiyun Li Hong Zhang 《DeCarbon》 2025年第2期10-23,共14页
Through strategies such as process optimization,solvent selection,and component tuning,the crystallization of perovskite materials has been effectively controlled,enabling perovskite solar cells(PSCs)to achieve over 2... Through strategies such as process optimization,solvent selection,and component tuning,the crystallization of perovskite materials has been effectively controlled,enabling perovskite solar cells(PSCs)to achieve over 25%power conversion efficiency(PCE).However,as PCE continues to improve,interfacial issues within the devices have emerged as critical bottlenecks,hindering further performance enhancements.Recently,interfacial engineering has driven transformative progress,pushing PCEs to nearly 27%.Building upon these developments,this review first summarizes the pivotal role of interfacial modifications in elevating device performance and then,as a starting point,provides a comprehensive overview of recent advancements in normal,inverted,and tandem structure devices.Finally,based on the current progress of PSCs,preliminary perspectives on future directions are presented. 展开更多
关键词 Perovskite solar cells Interfacial engineering Defect passivation Energy level alignment Ion migration Device stability
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Stratigraphic Forward Modeling of Late Quaternary Fluvial Dynamics in the Indus River Delta, Pakistan: Insights into Sea Level-Driven Sedimentary Evolution 被引量:1
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作者 HASSAN Hafiz Ahmed Raza LIU Keyu +3 位作者 LIU Jianliang MUNAWAR Muhammad Jawad REHMAN Saif Ur HUSSAIN Abid 《Journal of Ocean University of China》 2025年第6期1500-1518,共19页
Fluvial systems play a crucial role in coastal and riverine ecosystems, making it essential to understand their responses to sea level changes for preserving biodiversity and managing natural resources. The evolution ... Fluvial systems play a crucial role in coastal and riverine ecosystems, making it essential to understand their responses to sea level changes for preserving biodiversity and managing natural resources. The evolution of the modern Indus River Delta offers a rare opportunity to study the interplay between sea level fluctuations, tectonism, sediment supply, and the corresponding fluvial responses. This study employs the ‘SedSim' stratigraphic forward model to simulate the delta's evolution from 200 kyr to the next5 kyr, drawing on data from field observations, Landsat imagery, digital elevation models, and previous studies. The model consists of 205 layers, each representing a 1-kyr time step, covering the last two glacial-interglacial cycles. Between 200 kyr and 130 kyr, during a lowstand period, sedimentation on the delta plain continued due to partial flow from the Indus River. During the last interglacial(130–60 kyr), rising sea levels led to peak sediment deposition, characteristic of a highstand phase. From 60 kyr to 18 kyr, sea levels dropped to their lowest during the Last Glacial Maximum(LGM), resulting in extensive erosion and minimal deposition on the delta plain. From 18 kyr to the present, rapidly rising sea levels, coupled with intensified monsoon activity, increased sedimentation rates and triggered avulsion and aggradation processes. The model accurately predicted depositional thickness across the delta plain, indicating a maximum of ca. 200 m at the shoreline platform, ca. 175 m in the northeastern delta, and ca. 100 m in the central delta. The study underscores the delta's vulnerability to future sea level rise, which–at a projected rate of 1 m/kyr–could significantly influence the densely populated, low-lying delta plain. These findings offer valuable insights into the geomorphic evolution of the Indus Delta and emphasize the socioeconomic implications of sea level change, underscoring the importance of proactive management and adaptation strategies. 展开更多
关键词 fluvial responses sea level changes glacial-interglacial cycle sedimentary evolution stratigraphic forward modeling Indus Delta
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Effect of hospital-community-home collaborative health management on symptoms,cognition,anxiety,and depression in high-risk individuals for stroke 被引量:1
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作者 Jing Wang Chen-Xi Zhao +5 位作者 Jin Tian Yan-Ru Li Kai-Fang Ma Rui Du Meng-Kun Li Rui Hu 《World Journal of Psychiatry》 2025年第3期78-87,共10页
BACKGROUND Effective health management for high-risk stroke populations is essential.The hospital-community-home(HCH)collaborative health management(CHM)model leverages resources from hospitals,communities,and familie... BACKGROUND Effective health management for high-risk stroke populations is essential.The hospital-community-home(HCH)collaborative health management(CHM)model leverages resources from hospitals,communities,and families.By integrating patient information across these three domains,it facilitates the delivery of tailored guidance,health risk assessments,and three-in-one health education.AIM To explore the effects of the HCH-CHM model on stroke risk reduction in highrisk populations.METHODS In total,110 high-risk stroke patients screened in the community from January 2019 to January 2023 were enrolled,with 52 patients in the control group receiving routine health education and 58 in the observation group receiving HCH-CHM model interventions based on routine health education.Stroke awareness scores,health behavior levels,medication adherence,blood pressure,serum biochemical markers(systolic/diastolic blood pressure,total cholesterol,and triglyceride),and psychological measures(self-rating anxiety/depression scale)were evaluated and compared between groups.RESULTS The observation group showed statistically significant improvements in stroke awareness scores and health behavior levels compared to the control group(P<0.05),with notable enhancements in lifestyle and dietary habits(P<0.05)and reductions in postintervention systolic blood pressure,diastolic blood pressure,total cholesterol,triglyceride,self-rating anxiety scale,and self-rating depression scale scores(P<0.05).CONCLUSION The HCH-CHM model had a significant positive effect on high-risk stroke populations,effectively increasing disease awareness,improving health behavior and medication adherence,and appropriately ameliorating blood pressure,serum biochemical marker levels,and negative psychological symptoms. 展开更多
关键词 Hospital-community-home-collaborative health management model High-risk populations for stroke Stroke awareness score Health behavior level Hospital-community-home
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Characteristics and outcomes of trauma patients with unplanned intensive care unit admissions:Bounce backs and upgrades comparison 被引量:1
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作者 Alexander A Fokin Joanna Wycech Knight +4 位作者 Phoebe K Gallagher Justin Fengyuan Xie Kyler C Brinton Madison E Tharp Ivan Puente 《World Journal of Critical Care Medicine》 2025年第2期105-120,共16页
BACKGROUND The need for an emergency upgrade of a hospitalized trauma patient from the floor to the trauma intensive care unit(ICU)is an unanticipated event with possible life-threatening consequences.Unplanned ICU ad... BACKGROUND The need for an emergency upgrade of a hospitalized trauma patient from the floor to the trauma intensive care unit(ICU)is an unanticipated event with possible life-threatening consequences.Unplanned ICU admissions are associated with increased morbidity and mortality and are an indicator of trauma service quality.Two different types of unplanned ICU admissions include upgrades(patients admitted to the floor then moved to the ICU)and bounce backs(patients admitted to the ICU,discharged to the floor,and then readmitted to the ICU).Previous studies have shown that geriatric trauma patients are at higher risk for unfavorable outcomes.AIM To analyze the characteristics,management and outcomes of trauma patients who had an unplanned ICU admission during their hospitalization.METHODS This institutional review board approved,retrospective cohort study examined 203 adult trauma patients with unplanned ICU admission at an urban level 1 trauma center over a six-year period(2017-2023).This included 134 upgrades and 69 bounce backs.Analyzed variables included:(1)Age;(2)Sex;(3)Comorbidities;(4)Mechanism of injury(MOI);(5)Injury severity score(ISS);(6)Glasgow Coma Scale(GCS);(7)Type of injury;(8)Transfusions;(9)Consultations;(10)Timing and reason for unplanned admission;(11)Intubations;(12)Surgical interventions;(13)ICU and hospital lengths of stay;and(14)Mortality.RESULTS Unplanned ICU admissions comprised 4.2%of total ICU admissions.Main MOI was falls.Mean age was 70.7 years,ISS was 12.8 and GCS was 13.9.Main injuries were traumatic brain injury(37.4%)and thoracic injury(21.7%),and main reason for unplanned ICU admission was respiratory complication(39.4%).The 47.3%underwent a surgical procedure and 46.8%were intubated.Average timing for unplanned ICU admission was 2.9 days.Bounce backs occurred half as often as upgrades,however had higher rates of transfusions(63.8%vs 40.3%,P=0.002),consultations(4.8 vs 3.0,P<0.001),intubations(63.8%vs 38.1%%,P=0.001),longer ICU lengths of stay(13.2 days vs 6.4 days,P<0.001)and hospital lengths of stay(26.7 days vs 13.0 days,P<0.001).Mortality was 25.6%among unplanned ICU admissions,31.9%among geriatric unplanned ICU admissions and 11.9%among all trauma ICU patients.CONCLUSION Unplanned ICU admissions constituted 4.2%of total ICU admissions.Respiratory complications were the main cause of unplanned ICU admissions.Bounce backs occurred half as often as upgrades,but were associated with worse outcomes. 展开更多
关键词 Unplanned intensive care unit admissions Trauma intensive care unit Bounce backs Upgrades Level 1 trauma center Geriatric trauma patients Quality of care indicator
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A 100-degree lithospheric magnetic field model constructed using MSS-1,Swarm-A,and CHAMP satellite data 被引量:1
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作者 JiaXuan Zhang Yan Feng +3 位作者 Pan Zhang YuXuan Lin XinWu Li Ya Huang 《Earth and Planetary Physics》 2025年第3期667-676,共10页
By combining data from the Challenging Minisatellite Payload(CHAMP),Swarm-A,and newest Macao Science Satellite-1(MSS-1) missions,we constructed a lithospheric magnetic field model up to spherical harmonic degree N = 1... By combining data from the Challenging Minisatellite Payload(CHAMP),Swarm-A,and newest Macao Science Satellite-1(MSS-1) missions,we constructed a lithospheric magnetic field model up to spherical harmonic degree N = 100.To isolate the lithospheric magnetic field signals,we utilized the latest CHAOS-8(CHAMP,Φrsted,and SAC-C 8) model and MGFM(Multisource Geomagnetic Field Model) to remove nonlithospheric sources,including the core field,magnetospheric field,ocean tidal field,and ocean circulation field.Subsequently,orbit-by-orbit processing was applied to both scalar and vector data,such as spherical harmonic high-pass filtering,singular spectrum analysis,and line leveling,to suppress noise and residual signals along the satellite tracks.With an orbital inclination of only 41°,MSS-1 effectively captures fine-scale lithospheric magnetic field signals in mid-to low-latitude regions.Its data exhibit a root mean square error of only 0.77 nT relative to the final model,confirming the high quality and utility of lithospheric field modeling.The resulting model exhibits excellent consistency with the MF7(Magnetic Field Model 7),maintaining a high correlation up to N = 90 and still exceeding 0.65 at N = 100.These results demonstrate the reliability and value of MSS-1 data in global lithospheric magnetic field modeling. 展开更多
关键词 lithospheric magnetic field Macao Science Satellite-1(MSS-1) line leveling Magnetic Field Model 7(MF7) singular spectrum analysis
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An Approximation Method for Singular Trudinger-Moser Inequality
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作者 ZHU Maochun XU Wenyan JIANG Rou 《应用数学》 北大核心 2025年第1期64-70,共7页
In this paper,we construct a power type functional which is the approximation functional of the Singular Trudinger-Moser functional.Moreover,we obtain the concentration level of the functional and show it converges to... In this paper,we construct a power type functional which is the approximation functional of the Singular Trudinger-Moser functional.Moreover,we obtain the concentration level of the functional and show it converges to the concentration level of singular Trudinger-Moser functional on the unit ball. 展开更多
关键词 Singular Trudinger-Moser inequality Approximation functional Concentration level
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