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Formation of secondary inorganic aerosol in a frigid urban atmosphere

《环境科学与工程前沿(英文)》 2022年 第16卷 第2期 doi: 10.1007/s11783-021-1452-0

摘要:

•Harbin showed relatively high threshold RH (80%) for apparent increase of SOR.

关键词: Haze     Sulfate     Nitrate     Heterogeneous chemistry     Biomass burning     Northeast China    

Reduction of CeO

Elena Yu. KONYSHEVA

《化学科学与工程前沿(英文)》 2013年 第7卷 第3期   页码 249-261 doi: 10.1007/s11705-013-1333-6

摘要: Reduction behavior of pure and doped CeO , the multi-phase La Sr CoO ? CeO , La Sr MnO ? CeO , and La Ni Fe O ? CeO composites, was studied under hydrogen containing atmosphere to address issues related to the improvement of electrochemical and catalytic performance of electrodes in fuel cells. The enhanced reduction of cerium oxide was observed initially at 800°C in all composites in spite of the presence of highly reducible transition metal cations that could lead to the increase in surface concentration of oxygen vacancies and generation of the electron enriched surface. Due to continuous reduction of cerium oxide in La Sr CoO ? CeO and La Sr MnO ? CeO (up to 10 h) composites the redox activity of the Ce /Ce pair could be suppressed and additional measures are required for reversible spontaneous regeneration of Ce . After 3 h exposure to H -Ar at 800°C the reduction of cerium oxides and perovskite phases in La Ni Fe O ? CeO composites was diminished. The extent of cerium oxide involvement in the reduction process varies with time, and depends on its initial deviation from oxygen stoichiometry (that results in the larger lattice parameter and the longer pathway for O transport through the fluorite lattice), chemical origin of transition metal cations in the perovskite, and phase diversity in multi-phase composites.

关键词: reduction of cerium oxide     composites     perovskites     catalyst under hydrogen containing atmosphere    

Modeling water and heat transfer in soil-plant-atmosphere continuum applied to maize growth under plastic

Meng DUAN, Jin XIE, Xiaomin MAO

《农业科学与工程前沿(英文)》 2019年 第6卷 第2期   页码 144-161 doi: 10.15302/J-FASE-2019258

摘要:

Based on our previous work modeling crop growth (CropSPAC) and water and heat transfer in the soil-plant-atmosphere continuum (SPAC), the model was improved by considering the effect of plastic film mulching applied to field-grown maize in North-west China. In CropSPAC, a single layer canopy model and a multi-layer soil model were adopted to simulate the energy partition between the canopy and water and heat transfer in the soil, respectively. The maize growth module included photosynthesis, growth stage calculation, biomass accumulation, and participation. The CropSPAC model coupled the maize growth module and SPAC water and heat transfer module through leaf area index (LAI), plant height and soil moisture condition in the root zone. The LAI and plant height were calculated from the maize growth module and used as input for the SPAC water and heat transfer module, and the SPAC module output for soil water stress conditions used as an input for maize growth module. We used , the representation of evaporation resistance, instead of the commonly used evaporation resistance to reflect the change of latent heat flux of soil evaporation under film mulching as well as the induced change in energy partition. The model was tested in a maize field at Yingke irrigation area in North-west China. Results showed reasonable agreement between the simulations and measurements of LAI, above-ground biomass and soil water content. Compared with the original model, the modified model was more reliable for maize growth simulation under film mulching and showed better accuracy for the LAI (with the coefficient of determination = 0.92, the root mean square of error RMSE= 1.23, and the Nush-Suttclife efficiency E = 0.87), the above-ground biomass (with = 0.96, RMSE= 7.17 t·ha and E = 0.95) and the soil water content in 0–1 m soil layer (with = 0.78, RMSE= 49.44 mm and E = 0.26). Scenarios were considered to simulate the influence of future climate change and film mulching on crop growth, soil water and heat conditions, and crop yield. The simulations indicated that the change of LAI, leaf biomass and yield are negatively correlated with temperature change, but the growing degree-days, evaporation, soil water content and soil temperature are positively correlated with temperature change. With an increase in the ratio of film mulching area, the evaporation will decrease, while the impact of film mulching on crop transpiration is not significant. In general, film mulching is effective in saving water, preserving soil moisture, increasing soil surface temperature, shortening the potential growth period, and increasing the potential yield of maize.

关键词: film mulching     growth stage     leaf area index     maize growth     water and heat transfer    

Developing a molecular platform for potential carbon dioxide fixing

Mette MIKKELSEN, Mikkel JØRGENSEN, Frederik C. KREBS,

《化学科学与工程前沿(英文)》 2010年 第4卷 第2期   页码 236-239 doi: 10.1007/s11705-009-0239-9

摘要: This paper presents an attempt to develop a new system for fixing carbon dioxide from the atmosphere. The proposed molecular system has been designed to have the capacity to spontaneously bind CO from the atmosphere with high affinity. The molecular system is furthermore designed to have the ability to liberate CO at a later stage in the process, i.e., in a separate compartment. The liberated CO presents a carbon neutral way of obtaining pure CO. The proposed molecular system is based on a small stable organic molecule that potentially have two forms: one without bound CO and one with bound CO. One class of molecules that undergo a reaction compatible with our purposal is the merocyanine dyes that exhibit photochromic properties. Based on this structural class of molecules, a system for the potential fixing of CO has been developed.

关键词: potential fixing     atmosphere     attempt     ability     purposal    

Thermogravimetric kinetic analysis of

SUKARNI,SUDJITO,Nurkholis HAMIDI,Uun YANUHAR,I.N.G. WARDANA

《能源前沿(英文)》 2015年 第9卷 第2期   页码 125-133 doi: 10.1007/s11708-015-0346-x

摘要: The thermal behavior of combustion in air atmosphere were investigated by performing experiments on STA PT1600 Thermal Analyzer at heating rates of 10°C/min, 40°C/min and 70°C/min and range of temperatures from room temperature to 1200°C. The kinetic parameters were evaluated by using Kissinger and Ozawa methods. The result showed that combustion occurred in five stages. Started with initial devolatilization, the main thermal decomposition and combustion process, transition stage, the combustion of char and the last stage was the slow burning reaction of residual char. In line with increasing heating rate, the mass loss rate increased as well, but it delayed the thermal decomposition processes toward higher temperatures. The average activation energy at the main thermal decomposition stage and the stage of char combustion were approximately 251 kJ/mol and 178 kJ/mol, respectively.

关键词: Nannochloropsis oculata     combustion     kinetic parameters     air atmosphere     thermogravimetric    

Optimized determination of airborne tetracycline resistance genes in laboratory atmosphere

Lu Song, Can Wang, Yizhu Wang

《环境科学与工程前沿(英文)》 2020年 第14卷 第6期 doi: 10.1007/s11783-020-1274-5

摘要: Abstract • Sampling parameters with high efficiency was determined. • Operational process to detect airborne ARGs was optimized. • Providing research basis to control airborne ARGs of a laboratory atmosphere Antibiotic resistance genes (ARGs) have been detected in various atmospheric environments. Airborne ARGs transmission presents the public health threat. However, it is very difficult to quantify airborne ARGs because of the limited availability of collectable airborne particulate matter and the low biological content of samples. In this study, an optimized protocol for collecting and detecting airborne ARGs was presented. Experimental results showed that recovery efficiency tended to increase initially and then declined over time, and a range of 550–780 copies/mm2 of capture loading was recommended to ensure that the recovery efficiency is greater than 75%. As the cell walls were mechanically disrupted and nucleic acids were released, the buffer wash protects ARGs dissolution. Three ratios of buffer volume to membrane area in buffer wash were compared. The highest concentrations of airborne ARGs were detected with 1.4 µL/mm2 buffer wash. Furthermore, the majority of the cells were disrupted by an ultrasonication pretreatment (5 min), allowing the efficiency ARGs detection of airborne samples. While, extending the ultrasonication can disrupt cell structures and gene sequence was broken down into fragments. Therefore, this study could provide a theoretical basis for the efficient filter collection of airborne ARGs in different environments. An optimized sampling method was proposed that the buffer wash was 1.4 µL/mm2 and the ultrasonication duration was 5 min. The indoor airborne ARGs were examined in accordance with the improved protocol in two laboratories. The result demonstrated that airborne ARGs in an indoor laboratory atmosphere could pose the considerable health risk to inhabitants and we should pay attention to some complicated indoor air environment.

关键词: Airborne tetracycline resistance genes     Filter sampling     Capture loading     Membrane pretreatment     Indoor laboratory atmosphere    

大气探测系统设计和工程建设

郑国光

《中国工程科学》 2000年 第2卷 第6期   页码 21-26

摘要:

文章分析了我国大气探测业务现状和大气探测技术发展趋势,阐述了我国大气探测系统设计和工程建设的基本思路和目标,介绍了即将开始建设的国家大中型建设项目——大气监测自动化系统的总体结构和建设的主要内容。文章也是对大气科学的工程化建设一文[1]的进一步阐述。

关键词: 大气探测     监测自动化     工程设计与建设    

Regeneration of Fe

Ruizhuang ZHAO, Ju SHANGGUAN, Yanru LOU, Jin SONG, Jie MI, Huiling FAN

《化学科学与工程前沿(英文)》 2010年 第4卷 第4期   页码 423-428 doi: 10.1007/s11705-010-0503-z

摘要: Regeneration of a high-temperature coal gas desulfurization sorbent is a key technology in its industrial applications. A Fe O -based high-temperature coal gas desulfurizer was prepared using red mud from steel factory. The influences of regeneration temperature, space velocity and regeneration gas concentration in SO atmosphere on regeneration performances of the desulfurization sorbent were tested in a fixed bed reactor. The changes of phase and the composition of the Fe O -based high-temperature coal gas desulfurization sorbent before and after regeneration were examined by X-ray diffraction(XRD) and X-ray Photoelectron spectroscopy(XPS), and the changes of pore structure were characterized by the mercury intrusion method. The results show that the major products are Fe O and elemental sulfur; the influences of regeneration temperature, space velocity and SO concentration in inlet on regeneration performances and the changes of pore structure of the desulfurization sorbent before and after regeneration are visible. The desulfurization sorbent cannot be regenerated at 500°C in SO atmosphere. Within the range of 600°C – 800°C, the time of regeneration becomes shorter, and the regeneration conversion increases as the temperature rises. The time of regeneration also becomes shorter, and the elemental sulfur content of tail gas increases as the SO concentration in inlet is increased. The increase in space velocity enhances the reactive course; the best VSP is 6000 h for regeneration conversion. At 800°C, 20 vol-% SO and 6000 h , the regeneration conversion can reach nearly to 90%.

关键词: high-temperature coal gas     Fe2O3 desulfurization sorbent     SO2 atmosphere     regeneration behaviors     sulfur recovery    

Recycling of heat discharged from bearing quenching

WEN Xin-lin, CI Tie-jun, ZHANG Rong-ying, WEN Peng

《机械工程前沿(英文)》 2006年 第1卷 第4期   页码 472-474 doi: 10.1007/s11465-006-0062-7

摘要: In this paper, the technical method of cooling quench medium with air-cooler in the process of bearing quenching is introduced. The exhausted hot air is directly used to dry bearing balls. It is a novel approach for full utilization of heat energy during heat treatment, which increased 30 % of the heat efficiency when compared with normal air-cooler methods that directly put exhaust air into atmosphere.

关键词: process     utilization     technical     efficiency     atmosphere    

大气悬浮颗粒PM10对感烟火灾探测器本底效应研究

谢启源,袁宏永,蒋亚龙

《中国工程科学》 2003年 第5卷 第6期   页码 84-87

摘要:

针对大气污染引起的悬浮颗粒,尤其是可吸入颗粒(PM10)对感烟火灾探测器产生的本底效应进行了分析,并以离子型感烟探测器为例对本底值进行计算,通过比较,显示不同程度的大气颗粒物污染对感烟探测器本底影响的差异极小,排除了感烟探测器在悬浮颗粒污染严重地区发生灵敏度和误报率升高的可能。确认目前各国感烟火灾探测器检测标准对灵敏度指标的规定可以统一,粒子计数等高分辨率颗粒浓度测量技术的发展将使该本底效应的影响不可忽略。

关键词: 悬浮颗粒     火灾探测     本底效应    

Characteristics of mass distributions of aerosol particle and its inorganic water-soluble ions in summer over a suburb farmland in Beijing

ZHAO Peng, ZHU Tong, LIANG Baosheng, HU Min, KANG Ling, GONG Jicheng

《环境科学与工程前沿(英文)》 2007年 第1卷 第2期   页码 159-165 doi: 10.1007/s11783-007-0028-y

摘要: Agricultural activity is one of the most important sources of aerosol particles. To understand the mass distribution and sources of aerosol particles and their inorganic water-soluble ions in a suburb farmland of Beijing, particle samples were collected using a microorifice uniform deposit impactor (MOUDI) in the summer of 2004 in a suburb vegetable field. The distribution of the particles and their inorganic water-soluble ions in the diameter range of 0.18 18 mm were measured. The dominant fine particle ions were SO, NO, and NH. The association of day-to-day variation of the concentration of these ions with temperature, humidity, and solar radiation suggested that they are formed by the reaction of NH3 released from the vegetable field with the acid species produced from photochemical reactions. Fine particle K is likely from vegetation emission and biomass burning. Coarse particles like Ca, Mg, NO, and SO are suggested to come from the mechanical process by which the soil particle entered the atmosphere, and from the reaction of the acid species at the surface of the soil particle. The results show that fertilizer and soil are important factors determining the aerosol particle over agricultural fields, and vegetable fields in suburban Beijing contribute significantly to the aerosol particle.

关键词: diameter     atmosphere     suburban     contribute     agricultural    

标题 作者 时间 类型 操作

Formation of secondary inorganic aerosol in a frigid urban atmosphere

期刊论文

Reduction of CeO

Elena Yu. KONYSHEVA

期刊论文

Modeling water and heat transfer in soil-plant-atmosphere continuum applied to maize growth under plastic

Meng DUAN, Jin XIE, Xiaomin MAO

期刊论文

Developing a molecular platform for potential carbon dioxide fixing

Mette MIKKELSEN, Mikkel JØRGENSEN, Frederik C. KREBS,

期刊论文

Thermogravimetric kinetic analysis of

SUKARNI,SUDJITO,Nurkholis HAMIDI,Uun YANUHAR,I.N.G. WARDANA

期刊论文

Optimized determination of airborne tetracycline resistance genes in laboratory atmosphere

Lu Song, Can Wang, Yizhu Wang

期刊论文

大气探测系统设计和工程建设

郑国光

期刊论文

Regeneration of Fe

Ruizhuang ZHAO, Ju SHANGGUAN, Yanru LOU, Jin SONG, Jie MI, Huiling FAN

期刊论文

Recycling of heat discharged from bearing quenching

WEN Xin-lin, CI Tie-jun, ZHANG Rong-ying, WEN Peng

期刊论文

大气悬浮颗粒PM10对感烟火灾探测器本底效应研究

谢启源,袁宏永,蒋亚龙

期刊论文

Characteristics of mass distributions of aerosol particle and its inorganic water-soluble ions in summer over a suburb farmland in Beijing

ZHAO Peng, ZHU Tong, LIANG Baosheng, HU Min, KANG Ling, GONG Jicheng

期刊论文