资源类型

期刊论文 370

会议视频 5

年份

2024 1

2023 36

2022 34

2021 30

2020 21

2019 25

2018 18

2017 15

2016 21

2015 17

2014 12

2013 9

2012 15

2011 13

2010 24

2009 15

2008 18

2007 16

2006 8

2005 4

展开 ︾

关键词

大气污染 4

“一带一路” 2

仿真 2

农业面源污染 2

动力气垫 2

发展 2

发展前景 2

地效翼船 2

数值模拟 2

温度控制 2

面源污染 2

300 M钢 1

CFD 1

COVID-19 1

FLTD型脉冲加速器 1

GIS 1

IFOC 1

NOx 1

展开 ︾

检索范围:

排序: 展示方式:

Performance analysis of an air-source heat pump using an immersed water condenser

Jie JI, Huide FU, Hanfeng HE, Gang PEI,

《能源前沿(英文)》 2010年 第4卷 第2期   页码 234-245 doi: 10.1007/s11708-009-0056-3

摘要: A distributed model of an air-source heat pump (ASHP) system and its experimental setup using an immersed water condenser were presented. Dynamic performance of the ASHP was then evaluated by both simulation and experiment. The results indicated that the system coefficient of performance (COP) decreased as the condenser temperature increased, ranging from 4.41 to 2.32 with the average COP equaling 3.29 during the experiment. Comparisons between simulation results and experimental measurements demonstrated that the model was able to yield satisfactory predictions. Furthermore, temperature profiles of the refrigerant in the evaporator and condenser were also given. This paper provides the theoretical and experimental background for ASHP system optimization and a valuable reference for a solar air-source heat pump water heater when the solar irradiation energy is insufficient on cloudy or rainy days.

关键词: air-source     heat pump     distributed model     immersed water condenser    

基于平板热管的新型直膨式辐射可调节供暖末端 Article

吴一凡, 孙弘历, 段梦凡, 林波荣, 赵恒昕, 刘兆鸿

《工程(英文)》 2023年 第20卷 第1期   页码 192-207 doi: 10.1016/j.eng.2021.09.019

摘要:

建筑供暖电气化是实现碳中和目标的有效途径。作为一种清洁和可持续的电气化供暖技术,空气源热泵被广泛应用于缺乏集中供暖的地区。然而,现有末端形式存在难以同时实现间歇性和舒适性,且作为主要构件尚未较好地与空气源热泵匹配等问题。因此,本研究提出了一种与空气源热泵结合的新型辐射可调节供暖末端,以实现电气化节能减碳、间歇性和更好的热舒适性。针对辐射供暖末端目前存在三个主要问题,分别是峰值供热量受限、可调节性受限以及难以与空气源热泵结合,本文通过改进末端结构设计(改进A~E)提供了有效解决方案。研究结果表明,新末端能够将峰值供热量提升23.6%,并为使用者提供从10.1%到30.9%的可调辐射比。在此基础上,巧妙地借助平板热管减少了原有直膨式辐射供暖末端的制冷剂管路长度,进而改善了供暖末端的稳定性(利于回油)、间歇性(降低热惯性)和安全性(降低制冷剂泄漏风险)。此外,本文基于新末端提出了一种新的分阶段运行策略,可进一步提升末端的可调节性。本研究可以为电气化供暖助力建筑低碳提供一定参考。

关键词: 新型供暖末端     空气源热泵     结构优化设计     峰值供热能力     快速可调节性     房间温度分布    

The source and transport of bioaerosols in the air: A review

《环境科学与工程前沿(英文)》 2021年 第15卷 第3期 doi: 10.1007/s11783-020-1336-8

摘要:

• Emission of microbe from local environments is a main source of bioaerosols.

关键词: Bioaerosols     Diffusion     Source identification     Biogeography    

HOTSPOTS OF NUTRIENT LOSSES TO AIR AND WATER: AN INTEGRATED MODELING APPROACH FOR EUROPEAN RIVER BASINS

《农业科学与工程前沿(英文)》 2023年 第10卷 第4期   页码 579-592 doi: 10.15302/J-FASE-2023526

摘要:

Nutrient pollution of air and water is a persistent problem in Europe. However, the pollution sources are often analyzed separately, preventing the formulation of integrative solutions. This study aimed to quantify the contribution of agriculture to air, river and coastal water pollution by nutrients. A new MARINA-Nutrients model was developed for Europe to calculate inputs of nitrogen (N) and phosphorus (P) to land and rivers, N emissions to air, and nutrient export to seas by river basins. Under current practice, inputs of N and P to land were 34.4 and 1.8 Tg·yr–1, respectively. However, only 12% of N and 3% of P reached the rivers. Agriculture was responsible for 55% of N and sewage for 67% of P in rivers. Reactive N emissions to air from agriculture were calculated at 4.0 Tg·yr–1. Almost two-fifths of N emissions to air were from animal housing and storage. Nearly a third of the basin area was considered as pollution hotspots and generated over half of N emissions to air and nutrient pollution in rivers. Over 25% of river export of N ended up in the Atlantic Ocean and of P in the Mediterranean Sea. These results could support environmental policies to reduce both air and water pollution simultaneously, and avoid pollution swapping.

关键词: agriculture     air-water modeling     European rivers     nutrient pollution     sewage systems     source attribution    

城市大气污染源追踪“广义判识”与Nudging源同化集成技术途径

徐祥德,丁国安

《中国工程科学》 2012年 第14卷 第10期   页码 10-22

摘要:

提出了城市大气污染源追踪“广义判识”综合应用平台、模式源同化及其卫星遥感应用等新技术。“广义判识”综合应用平台包括气溶胶源主因子分析方法、气溶胶周期变化谱分析法、城市冠层大气污染变化规律同位相特性分析、追溯远距离空气污染源的合成风场相关矢量法、后向轨迹示踪法和边界层影响足痕分析法;另外,为解决长期以来大气污染模式中排放源不确定性的关键技术难点,采用源同化牛顿逼近Nudging技术,获取具有季节、月变化动态变化特征的SO2、NO2区域反演源排放清单。将卫星遥感资料应用在同化模型,探索空气污染预报模式的卫星遥感产品应用技术,卫星遥感—地基观测综合分析平台亦可广泛地应用于城市污染源追踪、城市雾和城市热岛的研究,并提出多圈层水—土—气综合分析方法是一种追踪水污染源的探索性尝试

关键词: 广义判识     源同化     污染源追踪     卫星遥感—地基     水—土—气    

induced by interaction burning of tri-symmetric propane fires in open space based on weighted multi-point source

Jie JI, Junrui DUAN, Huaxian WAN

《能源前沿(英文)》 2022年 第16卷 第6期   页码 1017-1026 doi: 10.1007/s11708-020-0716-x

摘要: The interaction of multiple fires may lead to a higher flame height and more intense radiation flux than a single fire, which increases the possibility of flame spread and risks to the surroundings. Experiments were conducted using three burners with identical heat release rates (HRRs) and propane as the fuel at various spacings. The results show that flames change from non-merging to merging as the spacing decreases, which result in a complex evolution of flame height and merging point height. To facilitate the analysis, a novel merging criterion based on the dimensionless spacing / was proposed. For non-merging flames ( / >0.368), the flame height is almost identical to a single fire; for merging flames ( / ≤0.368), based on the relationship between thermal buoyancy and thrust (the pressure difference between the inside and outside of the flame), a quantitative analysis of the flame height, merging point height, and air entrainment was formed, and the calculated merging flame heights show a good agreement with the measured experimental values. Moreover, the multi-point source model was further improved, and radiation fraction of propane was calculated. The data obtained in this study would play an important role in calculating the external radiation of propane fire.

关键词: flame interaction     air entrainment     flame height     multi-point source model     thermal radiation    

Indoor carbonyl compounds in an academic building in Beijing, China: concentrations and influencing factors

Chuanjia JIANG, Pengyi ZHANG

《环境科学与工程前沿(英文)》 2012年 第6卷 第2期   页码 184-194 doi: 10.1007/s11783-011-0309-3

摘要: Carbonyl compounds in indoor air are of great concern for their adverse health effects. Between February and May, 2009, concentrations of 13 carbonyl compounds were measured in an academic building in Beijing, China. Total concentration of the detected carbonyls ranged from 20.7 to 189.1 μg·m , and among them acetone and formaldehyde were the most abundant, with mean concentrations of 26.4 and 22.6 μg·m , respectively. Average indoor concentrations of other carbonyls were below 10 μg·m . Principal component analysis identified a combined effect of common indoor carbonyl sources and ventilation on indoor carbonyl levels. Diurnal variations of the carbonyl compounds were investigated in one office room, and carbonyl concentrations tended to be lower in the daytime than at night, due to enhanced ventilation. Average concentrations of carbonyl compounds in the office room were generally higher in early May than in late February, indicating the influence of temperature. Carbonyl source emission rates from both the room and human occupants were estimated during two lectures, based on one-compartment mass balance model. The influence of human occupants on indoor carbonyl concentrations varies with environmental conditions, and may become significant in the case of a large human occupancy.

关键词: carbonyl compounds     indoor air     ventilation     human occupancy     source emission rate (SER)     principal component analysis (PCA)    

真实空气中TNT装药爆炸近区冲击波传播特性研究

周丰峻,郑磊,孙云厚,张鏖,夏明

《中国工程科学》 2017年 第19卷 第6期   页码 18-26 doi: 10.15302/J-SSCAE-2017.06.004

摘要:

本文基于点源爆炸理论,建立了面源、线源和点源TNT装药强爆炸解,填补了面源与线源强爆炸解的空白;采用真实空气状态方程进行分析计算,研究了真实空气条件下球形TNT装药爆炸近区冲击波的传播特性。通过算例分析,计算结果与已有文献资料数据吻合较好。本文的研究成果对爆炸力学和防护工程研究起到了重要的参考作用。

关键词: TNT装药爆炸     真实空气状态方程     面源装药     线源装药     点源装药     抗爆防护    

Development of source profiles and their application in source apportionment of PM

Ningning Zhang, Mazhan Zhuang, Jie Tian, Pengshan Tian, Jieru Zhang, Qiyuan Wang, Yaqing Zhou, Rujin Huang, Chongshu Zhu, Xuemin Zhang, Junji Cao

《环境科学与工程前沿(英文)》 2016年 第10卷 第5期 doi: 10.1007/s11783-016-0879-1

摘要: Seasonal and spatial distribution of PM and its component were shown. Local source profiles of major PM sources were developed. Source apportionment was conducted using CMB model. Inorganic secondary components is the biggest contribution at Xiamen. Ambient PM samples were collected at four sites in Xiamen, including Gulangyu (GLY), Hongwen (HW), Huli (HL) and Jimei (JM) during January, April, July and October 2013. Local source samples were obtained from coal burning power plants, industries, motor vehicles, biomass burning, fugitive dust, and sea salt for the source apportionment studies. The highest value of PM mass concentration and species related to human activities (SO , NO , Pb, Ni, V, Cu, Cd, organic carbon (OC) and elemental carbon (EC)) were found in the ambient samples from HL, and the highest and lowest loadings of PM and its components occurred in winter and summer, respectively. The reconstructed mass balance indicated that ambient PM consisted of 24% OM (organic matter), 23% sulfate, 14% nitrate, 9% ammonium, 9% geological material, 6% sea salt, 5% EC and 10% others. For the source profiles, the dominant components were OC for coal burning, motor vehicle, biomass burning and sea salt; SO for industry; and crustal elements for fugitive dust. Source contributions were calculated using a chemical mass balance (CMB) model based on ambient PM concentrations and the source profiles. GLY was characterized by high contributions from secondary sulfate and cooking, while HL and JM were most strongly affected by motor vehicle emissions, and biomass burning and fugitive dust, respectively. The CMB results indicated that PM from Xiamen is composed of 27.4% secondary inorganic components, 20.8% motor vehicle emissions, 11.7% fugitive dust, 9.9% sea salt, 9.3% coal burning, 5.0% biomass burning, 3.1% industry and 6.8% others.

关键词: PM2.5     Source profile     Source apportionment     CMB     Xiamen    

δN-stable isotope analysis of NH: An overview on analytical measurements, source sampling and its source

《环境科学与工程前沿(英文)》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1414-6

摘要:

• Challenges in sampling of NH3 sources for d15N analysis are highlighted.

关键词: Aerosol ammonium     Atmospheric gaseous ammonia     Isotope fingerprinting     Isotope-based source apportionment     Ammonia gas-to-particle conversion    

Fault tolerant control strategy for modular PWM current source inverter

《能源前沿(英文)》 2023年 第17卷 第2期   页码 228-238 doi: 10.1007/s11708-022-0852-6

摘要: In this paper, a fault-tolerant control method for an input-series output-parallel modular grid-tied pulse-width modulation (PWM) current source inverter is proposed to address the most commonly seen single symmetrical gate-commutated thyristor (SGCT) open-circuit fault problems. This method actively offsets the neutral point of the current space vector to ensure a sinusoidal output of the grid current, and it can achieve the upper limit power of the inverter under the condition of a single SGCT open-circuit fault. In addition, an active damping control method based on grid harmonic current feedback is proposed after analyzing the influence of the transformer ferromagnetic resonance caused by the neutral point offset on the power quality of the grid current. It has been demonstrated that the proposed method effectively suppresses the resonance caused by the transformer and the modified modulation, improving the grid current’s power quality.

关键词: current source converter (CSC)     fault-tolerant control     space vector modulation     active damping     resonance suppression     power quality    

Intercontinental transport of air pollution

Lin ZHANG,

《环境科学与工程前沿(英文)》 2010年 第4卷 第1期   页码 20-29 doi: 10.1007/s11783-010-0014-7

摘要: There is an increasing interest on the intercontinental transport of air pollution among the three main emission regions at northern mid-latitudes: North America, Europe, and East Asia. Air pollutants with sufficient long lifetime can be transported from one continent to another. Observations from ground sites, aircraft and satellites have demonstrated this intercontinental-scale transport of air pollutants in the free troposphere. Numerical models have been applied to understand the pathways of the transport and the impact of intercontinental pollution transport. This paper reviews current observational evidence and modeling studies of intercontinental transport of ozone and its precursors, and the resulting impacts on air quality.

关键词: intercontinental transport     ozone     air pollution    

Health impacts of air pollution in China

《环境科学与工程前沿(英文)》 2021年 第15卷 第4期 doi: 10.1007/s11783-020-1367-1

摘要:

•Impacts of air pollution on various body systems health in China were highlighted.

关键词: Health impacts     Air pollution     China     Advances    

DITCHES AND PONDS CAN BE THE SOURCES OR SINKS OF NON-POINT SOURCE POLLUTION: OBSERVATIONS IN AN UPLAND

《农业科学与工程前沿(英文)》 2023年 第10卷 第4期   页码 607-626 doi: 10.15302/J-FASE-2023517

摘要:

As the common features of agroecosystems, ditches and ponds benefit the irrigation and drainage, as well as intercepting non-point source pollutants. However, most ditch-pond studies have been conducted in lowland areas. To test this source-sink assumption in upland areas, this study made observations on the ecological function of the ditch and pond system in a typical catchment in China. First, the changes in ponds in the catchment were analyzed using high-resolution remote sensing data. Then, the migration of agricultural pollutants in ditches and ponds were analyzed by field sampling and laboratory detection. The results showed that over the past 15 years the length of ditches in the catchment and the number of small ponds (< 500 m2) have increased by 32% and 75%, respectively. The rate of change in nutrient concentrations in the ditches and ponds were mostly from −20% to 20%, indicating ditches and ponds can be both sources and sinks for agricultural pollutants. Lastly, the contributing factors were explored and it was found that ditches and ponds are important sinks in dry season. However, during the rainy season, ditches and ponds become sources of pollutants, with the rapid drainage of ditches and the overflow of ponds in upland areas. The results of this study revealed that the ditches and ponds could be used for ecological engineering in upland catchments to balance drainage and intercept pollutants.

关键词: ditches     ponds     non-point source pollution     mountainous areas     nitrogen     phosphorus    

STRENGTHENING NON-POINT SOURCE POLLUTION CONTROL TO PROMOTE AGRICULTURAL GREEN DEVELOPMENT

《农业科学与工程前沿(英文)》 2023年 第10卷 第4期   页码 503-509 doi: 10.15302/J-FASE-2023528

摘要:

STRENGTHENING NON-POINT SOURCE POLLUTION CONTROL TO PROMOTE AGRICULTURAL GREEN DEVELOPMENT

关键词: GREEN     AGRICULTURAL     PROMOTE     POLLUTION     SOURCE     DEVELOPMENT     POINT     STRENGTHENING     CONTROL    

标题 作者 时间 类型 操作

Performance analysis of an air-source heat pump using an immersed water condenser

Jie JI, Huide FU, Hanfeng HE, Gang PEI,

期刊论文

基于平板热管的新型直膨式辐射可调节供暖末端

吴一凡, 孙弘历, 段梦凡, 林波荣, 赵恒昕, 刘兆鸿

期刊论文

The source and transport of bioaerosols in the air: A review

期刊论文

HOTSPOTS OF NUTRIENT LOSSES TO AIR AND WATER: AN INTEGRATED MODELING APPROACH FOR EUROPEAN RIVER BASINS

期刊论文

城市大气污染源追踪“广义判识”与Nudging源同化集成技术途径

徐祥德,丁国安

期刊论文

induced by interaction burning of tri-symmetric propane fires in open space based on weighted multi-point source

Jie JI, Junrui DUAN, Huaxian WAN

期刊论文

Indoor carbonyl compounds in an academic building in Beijing, China: concentrations and influencing factors

Chuanjia JIANG, Pengyi ZHANG

期刊论文

真实空气中TNT装药爆炸近区冲击波传播特性研究

周丰峻,郑磊,孙云厚,张鏖,夏明

期刊论文

Development of source profiles and their application in source apportionment of PM

Ningning Zhang, Mazhan Zhuang, Jie Tian, Pengshan Tian, Jieru Zhang, Qiyuan Wang, Yaqing Zhou, Rujin Huang, Chongshu Zhu, Xuemin Zhang, Junji Cao

期刊论文

δN-stable isotope analysis of NH: An overview on analytical measurements, source sampling and its source

期刊论文

Fault tolerant control strategy for modular PWM current source inverter

期刊论文

Intercontinental transport of air pollution

Lin ZHANG,

期刊论文

Health impacts of air pollution in China

期刊论文

DITCHES AND PONDS CAN BE THE SOURCES OR SINKS OF NON-POINT SOURCE POLLUTION: OBSERVATIONS IN AN UPLAND

期刊论文

STRENGTHENING NON-POINT SOURCE POLLUTION CONTROL TO PROMOTE AGRICULTURAL GREEN DEVELOPMENT

期刊论文