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Study on Phthalate Esters Pollution in the Soil of Facility Vegetable Base in Yangling District of Xianyang City
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作者 Guoxiu LI Lihui CUI +1 位作者 Wei LIU Xiaoning LIU 《Asian Agricultural Research》 2021年第10期37-40,共4页
[Objectives]To evaluate the pollution status of phthalate esters(PAEs)in the soil of facility vegetable base in Yangling District of Xianyang City.[Methods]A total of 15 kinds of PAEs in soil samples were detected and... [Objectives]To evaluate the pollution status of phthalate esters(PAEs)in the soil of facility vegetable base in Yangling District of Xianyang City.[Methods]A total of 15 kinds of PAEs in soil samples were detected and analyzed by gas chromatography-mass spectrometry.[Results]A total of 12 kinds of PAEs were detected in analyzed soil samples,with a total content of 53.4-3524.1μg/kg and an average of 602.7μg/kg.Specifically,DEHP,DBP,DIBP,DMEP,BBP and DNOP were the main PAEs pollutants in the soil,with the detection rates of 100%,100%,100%,73.3%,63.3%and 53.3%,and the average content were 286.3,167.3,123.1,157.6,121.3,and 130.5μg/kg,respectively.[Conclusions]Compared with the soil in other regions,the pollution level of PAEs in the soil of facility vegetable base in Yangling District is lower,but such compounds are widespread in the facility vegetable base,and their potential environmental risks should attract close attention. 展开更多
关键词 Phthalate esters(PAEs) vegetable base SOIL Pollution status
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Easy removing of phenol from wastewater using vegetable oil-based organic solvent in emulsion liquid membrane process 被引量:4
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作者 Norasikin Othman Norul Fatiha Mohamed Noah +4 位作者 Lim Yin Shu Zing-Yi Ooi Norela Jusoh Mariani Idroas Masahiro Goto 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第1期45-52,共8页
Phenol is considered as pollutant due to its toxicity and carcinogenic effect.Thus,variety of innovative methods for separation and recovery of phenolic compounds is developed in order to remove the unwanted phenol fr... Phenol is considered as pollutant due to its toxicity and carcinogenic effect.Thus,variety of innovative methods for separation and recovery of phenolic compounds is developed in order to remove the unwanted phenol from wastewater and obtain valuable phenolic compound.One of potential method is extraction using green based liquid organic solvent.Therefore,the feasibility of using palm oil was investigated.In this research,palm oil based organic phase was used as diluents to treat a simulated wastewater containing 300×10^(-6) of phenol solution using emulsion liquid membrane process(ELM).The stability of water-in-oil(W/O) emulsion on diluent composition and the parameters affecting the phenol removal efficiency and stability of the emulsion;such as emulsification speed,emulsification time,agitation speed,surfactant concentration,pH of external phase,contact time,stripping agent concentration and treat ratio were carried out.The results of ELM study showed that at ratio7 to 3 of palm oil to kerosene,5 min and 1300 r·min^(-1) of emulsification process the stabile primary emulsion were formed.Also,no carrier is needed to facilitate the phenol extraction.In experimental conditions of500 r·min^(-1) of agitation speed,3%Span 80,pH 8 of external phase,5 min of contact time,0.1 mol·L^(-1) NaOH as stripping agent and 1:10 of treat ratio,the ELM process was very promising for removing the phenol from the wastewater.The extraction performance at about 83%of phenol was removed for simulated wastewater and an enrichment of phenol in recovery phase as phenolate compound was around 11 times. 展开更多
关键词 苯酚溶液 模拟废水 膜法处理 乳化液 有机溶剂 油基 稳定性参数 酚类化合物
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Toward Cloud-Based Parking Facility Management System: A Preliminary Study 被引量:1
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作者 Chung-Yang Chen Wen-Lung Tsai Tzu-Yin Chen 《Journal of Electronic Science and Technology》 CAS 2013年第2期181-186,共6页
An e-tag used on the freeway is a kind of passive sensors composed of sensors and radio-frequency identification (RFID) tags. The principle of the electronic toll collection system is that the sensor emits radio waves... An e-tag used on the freeway is a kind of passive sensors composed of sensors and radio-frequency identification (RFID) tags. The principle of the electronic toll collection system is that the sensor emits radio waves touching the e-tag within a certain range, the e-tag will respond to the radio waves by induction, and the sensor will read and write information of the vehicles. Although the RFID technology is popularly used in campus management systems, there is no e-tag technology application used in a campus parking system. In this paper, we use the e-tag technology on a campus parking management system based on the cloud-based construction. By this, it helps to achieve automated and standardized management of the campus parking system, enhance management efficiency, reduce the residence time of the vehicles at the entrances and exits, and improve the efficiency of vehicles parked at the same time. 展开更多
关键词 电子不停车收费系统 设施管理系统 电子标签技术 校园管理系统 停车场管理系统 无源传感器 RFID技术 车辆信息
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Research Progress on N<sub>2</sub>O Emissions from Soil in Facility Vegetable Plot
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作者 Weihan Wang 《Journal of Geoscience and Environment Protection》 2018年第12期171-175,共5页
N2O is one of the important greenhouse gases that cause global warming. N2O emissions from the soil of the facility vegetable land are an important source. It is important to summarize the research on the N2O emission... N2O is one of the important greenhouse gases that cause global warming. N2O emissions from the soil of the facility vegetable land are an important source. It is important to summarize the research on the N2O emissions from the soil in the facility vegetable land, and is also of great significance to study on the emission mechanism of N2O in China’s agricultural fields. This paper summarizes the development status of the facility vegetable plot in China, tracks the progress of soil N2O emission research in the facility vegetable plot, and makes a prospect of the research in this field. 展开更多
关键词 facility vegetable PLOT N2O EMISSIONS
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Investigation and Research on the Current Status of Fertilization in Facility Vegetables of Shandong Province
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作者 Ronghui MA Lihua JIANG +8 位作者 Ni LI Yu XU Jing SHI Yan YANG Mei WANG Jianjun XIAO Zhongtao LI Hongjun GUO Yansheng LIU 《Agricultural Biotechnology》 CAS 2020年第3期83-89,共7页
In order to clarify the current situation and main problems in facility vegetable fertilization and guide farmers to fertilize scientifically,an investigation on the yield and fertilization of facility vegetables( tom... In order to clarify the current situation and main problems in facility vegetable fertilization and guide farmers to fertilize scientifically,an investigation on the yield and fertilization of facility vegetables( tomato,cucumber,eggplant and celery) was carried out in six districts and counties in Shandong Province from 2016 to 2017. The results showed that among the four vegetables,the yield levels of eggplant and celery varied slightly with the coefficient of variation between 7. 18% and 27. 63%,and the yield levels of tomato and cucumber varied greatly with the coefficient of variation between 33. 84% and 65. 15%. In terms of fertilization,the differences in N,P2O5 and K2O inputs in cucumber was the largest,and the maximum values of the nutrient inputs were 7. 95,8. 54 and 8. 77 times of the corresponding minimum values,respectively. The input amounts of N,P2O5 and K2O in tomato,cucumber and eggplant were 1. 47-2. 68,3. 93-7. 50 and1. 09-1. 51 times of the corresponding demands,respectively. The N and P2O5 inputs of celery exceeded the demands by 32. 00% and 79. 00%,respectively,while the K2O input was only 49. 00% of the demand. The ratios of N∶ P2O5∶ K2O input in the total application amount,organic fertilizer,base fertilizer and topdressing chemical fertilizer of facility vegetables were,respectively,1∶ 0. 84∶ 1. 02,1∶ 0. 84∶ 0. 80,1∶ 0. 99∶ 1. 05 and 1∶ 0. 77∶ 1. 25. The proportion of P2O5 input was too high,while the proportion of K2O input coming from the organic fertilizer was insufficient. The average proportions of organic fertilizer in N,P2O5 and K2O inputs were 43. 96%,43. 72% and 36. 99% respectively. The proportions of organic fertilizer in N and P2O5 inputs were reasonable,while that in K2O was lower.In N,P2O5 and K2O inputs of different vegetables,the proportions from organic fertilizer were reasonable in cucumber,higher in eggplant and lower in tomato and celery. The recommendations were presented in this paper that the inputs of N and P2O5 should be reduced,and the inputs of K2O and organic fertilizer should be increased,while farmers should choose fertilizer with low P2O5 and high K2O contents. 展开更多
关键词 facility vegetable FERTILIZATION INVESTIGATION Shandong
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Effect of Combined Foliar Spray on Heavy Metals Accumulation in Facility Fruit Vegetables
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作者 Huiwei ZHAO Jumei LI +3 位作者 Xueping SHI Yiming LIU Chuan LU Shuo SUN 《Agricultural Biotechnology》 CAS 2020年第5期32-36,共5页
In order to explore the effects of combined foliar spray which was prepared from potassium fulvate and Zn on heavy metal accumulations in three kinds of facility fruit vegetables,cucumber,tomato and white melon,the fo... In order to explore the effects of combined foliar spray which was prepared from potassium fulvate and Zn on heavy metal accumulations in three kinds of facility fruit vegetables,cucumber,tomato and white melon,the foliar spray was applied from fruit setting to maturation.The results showed that the combined foliar spray significantly promoted the absorption of Zn and Cu in the three fruit vegetables,blocked the absorption of Cr,As and Pb in cucumber,significantly blocked the absorption of Cd in white melon,blocked the absorption of Pb in white melon,and showed a tendency of blocking the absorption of heavy metals Cd and As in tomato. 展开更多
关键词 Foliar spray facility fruit vegetables Accumulation of heavy metals IMPACT
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Biochemical Characterization of Three Vegetable Based Fermented Food Products (<i>Hungrii, Rhujuk</i>and <i>Tsutuocie</i>) of Nagaland, India
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作者 Bendangnaro Jamir Chitta Ranjan Deb 《Natural Resources》 2021年第2期34-43,共10页
<span style="font-family:Verdana;">I</span><span style="font-family:""><span style="font-family:Verdana;">ndigenous fermented foods are important constituent ... <span style="font-family:Verdana;">I</span><span style="font-family:""><span style="font-family:Verdana;">ndigenous fermented foods are important constituent of staple diet of the Naga tribes of India. In Nagaland, there are variety of fermented foods and beverages with traditional and cultural value. Agriculture being the main occupation, preservation technique of perishable crops has been passed down from generation to generation. Here we present the biochemical characterization of some vegetable based fermented food products of Nagaland </span><i><span style="font-family:Verdana;">i.e.</span></i><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Hungrii</span></i><span style="font-family:Verdana;"> (</span><i><span style="font-family:Verdana;">Brassica</span></i><span style="font-family:Verdana;"> leaves), </span><i><span style="font-family:Verdana;">Rhujuk</span></i><span style="font-family:Verdana;">/</span><i><span style="font-family:Verdana;">Bastanga</span></i><span style="font-family:Verdana;"> (Bamboo shoot) and </span><i><span style="font-family:Verdana;">Tsutuocie </span></i><span style="font-family:Verdana;">(Cucumber). The comparative account of nutritive values like moisture content, pH, protein content, reducing sugars, crude fibre, total phenol content, flavonoid content and antioxidant activity of fermented foods and its constitu</span><span style="font-family:Verdana;">ent raw materials was done. Results indicated high amounts of protein in</span> <i><span style="font-family:Verdana;">Hungrii </span></i><span style="font-family:Verdana;">(34.07 g/100g). Most of the fermented foods had low moisture content rendering it to have longer shelf life. </span><i><span style="font-family:Verdana;">Rhujuk</span></i><span style="font-family:Verdana;">/</span><i><span style="font-family:Verdana;">Bastanga</span></i><span style="font-family:Verdana;"> was found to have significantly higher levels of phenolic content (1.44 mg GAE/g and 2.44 mg </span><span style="font-family:Verdana;">GAE/g), thus having high antioxidant activity in comparison to the other</span> <span style="font-family:Verdana;">fermented products. This present study thus puts some light on the prox</span><span style="font-family:Verdana;">imate composition as well as the antioxidant content of some major vegetable based fermented food products of Nagaland so as to popularize these products as nutritional support to the region for health improvement. 展开更多
关键词 Bastanga/Rhujuk Hungrii Nagaland Tsutuocie vegetable based Fermented Foods
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Does Facility Based Sexual and Reproductive Health Services Meet the Needs of Young Persons? Views from Cross Section of Ghanaian Youth
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作者 Jonathan Mensah Dapaah Seth Christopher Yaw Appiah +2 位作者 Eric Badu Bernard Obeng Victoria Ampiah 《Advances in Sexual Medicine》 2015年第3期61-71,共11页
The focus on facility based health setting to provide sexual and reproductive health to the youth has been tested in several settings and achieved varying results. This study examined whether facility based sexual and... The focus on facility based health setting to provide sexual and reproductive health to the youth has been tested in several settings and achieved varying results. This study examined whether facility based sexual and reproductive health services met the needs of Ghanaian youth. Adopting the descriptive cross sectional design, 170 youths between the ages of 10 and 24 were sampled. A three-stage stratified random sampling technique was adopted. The results of the study are presented using descriptive statistics. The study established that a total of 55.8% (95/170) of the youth had utilized at least one or more of a sexual and reproductive health service in life time. However, only 45.2% (43/95) of youth used or accessed sexual and reproductive health services from a facility based setting. Facility based sexual and reproductive health service provided specifically for the youth is very limited. This calls for the provision of out-of health facility services located within the communities and at strategic places while ensuring confidentiality to the youth. More rigorous research is recommended on a national scale to examine youth preference for the type of facility based and out-of-facility based sexual and reproductive health services to meet the needs of young people. 展开更多
关键词 facility-based Sexual and REPRODUCTIVE Health YOUNG PERSONS YOUTH Needs Ghana
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设施蔬菜产业发展(五) 我国老旧蔬菜设施现状、问题及改造提升对策建议
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作者 冷杨 孙周平 +5 位作者 魏晓明 别之龙 王克健 夏宏义 曹堃 周泽宇 《中国蔬菜》 北大核心 2024年第2期1-5,共5页
目前我国正在加快建设现代设施农业,推进老旧蔬菜设施改造升级,促进设施蔬菜产业的高质量发展。但是对老旧设施的现状和存在问题缺乏系统梳理,对如何破解改造工作面临的困难和提升改造对策缺乏系统研究。通过调研我国主要设施蔬菜产区,... 目前我国正在加快建设现代设施农业,推进老旧蔬菜设施改造升级,促进设施蔬菜产业的高质量发展。但是对老旧设施的现状和存在问题缺乏系统梳理,对如何破解改造工作面临的困难和提升改造对策缺乏系统研究。通过调研我国主要设施蔬菜产区,总结老旧设施现状及存在的主要问题,分析推进改造提升的主要制约因素,并提出明确工作重点、优化设施结构、完善工作机制、增强条件保障等方面的对策建议。 展开更多
关键词 老旧蔬菜设施 改造提升 对策
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Development of Maintenance Management Strategy Based on Reliability Centered Maintenance for Marginal Oilfield Production Facilities
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作者 Olawale D. Adenuga Ogheneruona E. Diemuodeke Ayoade O. Kuye 《Engineering(科研)》 CAS 2023年第3期143-162,共20页
The present work adopted Reliability Centered Maintenance (RCM) methodology to evaluate marginal oilfield Early Production Facility (EPF) system to properly understand its functional failures and to develop an efficie... The present work adopted Reliability Centered Maintenance (RCM) methodology to evaluate marginal oilfield Early Production Facility (EPF) system to properly understand its functional failures and to develop an efficient maintenance strategy for the system. The outcome of the RCM conducted for a typical EPF within the Niger Delta zone of Nigeria provides an indication of equipment whose failure can significantly affect operations at the production facility. These include the steam generation unit and the wellhead choke assembly, using a risk-based failure Criticality Analysis. Failure Mode and Effect Analysis (FMEA) was conducted for the identified critical equipment on a component basis. Each component of the equipment was analyzed to identify the failure modes, causes and the effect of the failure. The outcome of the FMEA analysis aided the development of a robust maintenance management strategy, which is based on an optimized mix of corrective, preventive and condition-based monitoring maintenance for the marginal oilfield EPF. 展开更多
关键词 Criticality Analysis Corrective Maintenance Condition-based Maintenance Early Production facility Preventive Maintenance Risk Priority Number
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广西设施蔬菜发展现状分析与对策
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作者 陈振东 李洋 +6 位作者 文俊丽 康德贤 宋焕忠 郭元元 张力 陈琴 孙晓妍 《广西科学院学报》 2024年第1期1-8,共8页
发展设施蔬菜种植,能有效提高蔬菜单位面积产量,增加农民种植收益,提升产品市场竞争力。但广西设施蔬菜播种面积占比仍不到3%,离我国设施蔬菜播种面积占比约18%的平均水平有较大差距,且存在产业布局不够合理、技术集成转化不够广泛、规... 发展设施蔬菜种植,能有效提高蔬菜单位面积产量,增加农民种植收益,提升产品市场竞争力。但广西设施蔬菜播种面积占比仍不到3%,离我国设施蔬菜播种面积占比约18%的平均水平有较大差距,且存在产业布局不够合理、技术集成转化不够广泛、规模化效应受限等问题。本文通过分析广西设施蔬菜产业的基础与现状,研判产业发展存在的问题和挑战,提出加快设施蔬菜生产结构调整、提升科技支撑水平、创新经营管理模式等对策建议,拟为广西蔬菜产业转型升级和高质量发展提供支撑。 展开更多
关键词 广西 设施蔬菜 产业发展 对策建议
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典型蔬菜基地土壤重金属污染风险评估及其源解析
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作者 徐圣友 郝展 +5 位作者 马明海 陈然 崔朋 程东华 石瑶 杨兴业 《温州大学学报(自然科学版)》 2024年第1期42-53,共12页
为探究典型蔬菜基地土壤重金属的污染特征,评估其生态风险,以黄山市徽州区蔬菜基地表层土壤为研究对象,采用多种污染评价方法对其土壤重金属进行风险评价,利用相关性分析与主成分分析法对其进行源解析.结果表明,蔬菜基地土壤pH整体呈酸... 为探究典型蔬菜基地土壤重金属的污染特征,评估其生态风险,以黄山市徽州区蔬菜基地表层土壤为研究对象,采用多种污染评价方法对其土壤重金属进行风险评价,利用相关性分析与主成分分析法对其进行源解析.结果表明,蔬菜基地土壤pH整体呈酸性,土壤重金属含量平均值大小为Cr>Zn> Cu> Pb> Ni> As> Cd;除Cd含量超过国家标准外,其余均合格,但均超出了安徽省土壤环境背景值,其中,Cd与As分别超标为422.68%与264.33%.土壤重金属污染指数平均值均大于1,其中,Cd与As的潜在污染指数值均大于3,达到重度污染水平.地累积指数评估结果显示,除重金属Cd为中度污染外,其余重金属均在轻度污染以下水平.重金属Cd的潜在生态风险等级在较强及以上,其余均为轻度.重金属来源途径多种,主要与人类生产活动和成土母质有关,其中,Cd、As污染主要来自于人为源.综上可见,蔬菜基地土壤整体生态风险较高,土壤重金属存在积累趋势,应防范其潜在危害. 展开更多
关键词 设施蔬菜基地 土壤 重金属 风险评价 来源解析
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氧化亚硫酸化菜籽油加脂剂的制备及性能研究
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作者 王璐瑶 陈向 +4 位作者 王雨璐 张佳星 贾欣宇 蒋弟勇 陈慧 《皮革科学与工程》 CAS 北大核心 2024年第1期75-82,共8页
利用亚硫酸氢钠对氧化菜籽油进行亚硫酸化改性,经过三乙醇胺中和获得植物油基加脂剂(OSF-T),最后通过添加过氧乙酸去除残余的亚硫酸盐获得低碘值加脂剂(OSF-PT)。将上述加脂剂应用于蓝湿牛皮染色加脂实验,同时与市售加脂剂AMK对比。结... 利用亚硫酸氢钠对氧化菜籽油进行亚硫酸化改性,经过三乙醇胺中和获得植物油基加脂剂(OSF-T),最后通过添加过氧乙酸去除残余的亚硫酸盐获得低碘值加脂剂(OSF-PT)。将上述加脂剂应用于蓝湿牛皮染色加脂实验,同时与市售加脂剂AMK对比。结果表明,自制加脂剂乳液粒径在10~180 nm之间,并具有优异的乳液稳定性和分散性;加脂性能良好,其中OSF-T加脂革柔软度可达6.5 mm;OSF-T加脂革的挥发性有机物(VOC)含量为123.7 g/m^(2),OSF-PT加脂革的VOC含量为121.3 g/m^(2),均低于AMK加脂革(164.3 g/m^(2));OSF-PT加脂革比AMK加脂革的颜色更浅淡,色差(ΔE)为4.12,更适用于浅色革加脂;经过热老化和紫外老化处理,OSF-T加脂革的抗张强度仍维持在15 MPa以上,六价铬含量低于5 mg/kg。加脂剂OSF-T在皮革柔软度、力学性能、耐老化性能和六价铬含量方面均略优于市售加脂剂AMK。 展开更多
关键词 氧化菜籽油 氧化亚硫酸化 植物油基加脂剂 耐老化性能
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Urban Planning Based on Nature—A Nature-Based Solution
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作者 Tomislav Đorđević 《Journal of Building Construction and Planning Research》 2023年第1期1-25,共25页
After an international contest announced by the City of Abu Dhabi “Cool Abu Dhabi Challenge”<sup>1</sup> and the article published as a digest of a paper titled A Nature-based Solution [1], the decision ... After an international contest announced by the City of Abu Dhabi “Cool Abu Dhabi Challenge”<sup>1</sup> and the article published as a digest of a paper titled A Nature-based Solution [1], the decision has been made to take part in improving thermal comfort in public spaces by mitigating the impact of the effect of Urban Heat Islands (UHI)<sup>2</sup> in the city of the Belgrade. The basic research aims at achieving the balance between the conflicting impacts when the buildings with their infrastructure and water-green surrounding area are in such correlation that it fulfils acceptable living and heating standards and reduces the use of fossil fuels for cooling the urban areas (buildings). By implementing the remote detection it is possible to analyze and quantify the impact of over-building on the temperature rise in urban areas as well as the disturbance of the heating comfort and the increased demand for additional cooling. Now it is possible to create virtual models that will incorporate this newly-added urban vegetation into urban plans, depending on the evaporation potential that will affect the microclimate of the urban area. Such natural cooling can be measured and adapted and hence aimed at a potential decrease in areas with UHI emissions [2]. Suitable greenery in the summer season can be a useful improvement which concurrently enables and complements several cooling mechanisms—evaporative cooling and evapotranspiration, i.e. natural cooling systems. The remote detection shall establish and map the “healthy” and “unhealthy” greenery zones—that is the vegetation zones with the highest evaporative potential with the “cooling by evaporation” effect and also, by implementing the urban prediction model, it shall propose green infrastructure corridors aimed at a potential decrease in the Urban Heat Island Emission. 展开更多
关键词 Nature-base Solution (NBS) Urban Heat Islands (UHI) Land Surface Temperature (LST) Land Use and Land Cover (LULC) Normalized Difference Vegetation Index (NDVI)
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我国居家社区养老服务设施利用状况分析与建设措施优化
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作者 张思锋 张恒源 《社会保障评论》 2024年第1期88-106,共19页
党的十九大以来,各级政府投入大量资源用于提高居家社区养老服务设施覆盖率。目前,已建成的设施利用状况不容乐观。本文在界定居家社区养老服务、机构、设施内涵及相互关系的基础上,参考安德森模型,构建了居家社区养老服务设施利用分析... 党的十九大以来,各级政府投入大量资源用于提高居家社区养老服务设施覆盖率。目前,已建成的设施利用状况不容乐观。本文在界定居家社区养老服务、机构、设施内涵及相互关系的基础上,参考安德森模型,构建了居家社区养老服务设施利用分析框架。通过对17个社区调查资料的描述性统计,发现已建成的居家社区养老服务设施尚未得到有效利用。运用二元Logistic回归分析,得出设施利用状况堪忧的主要原因:设施建设不符应老年人的多样化需要;老年人广义支付能力不足约束对设施的利用;设施供给结构不能激发老年人的支付意愿。建议进一步规范居家社区养老相关术语,更加明确居家养老的社区责任边界,充分发挥市场满足多样化养老需求的作用。 展开更多
关键词 居家养老 社区养老 养老服务设施 安德森模型
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参与电商能否促进设施蔬菜种植户绿色生产?——基于山东省五市十一县的微观调研
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作者 李全海 朱鹏 郑军 《中国人口·资源与环境》 CSCD 北大核心 2024年第2期106-118,共13页
引导设施蔬菜种植户实现绿色转型是保障国家“菜篮子”安全的重中之重。然而,中国设施蔬菜生产分散,不易于政府和消费者监管,种植户违规使用化肥农药的现象屡禁不止,仅从生产端发力恐难以实现上述目标。为此,该研究从销售端着手,基于山... 引导设施蔬菜种植户实现绿色转型是保障国家“菜篮子”安全的重中之重。然而,中国设施蔬菜生产分散,不易于政府和消费者监管,种植户违规使用化肥农药的现象屡禁不止,仅从生产端发力恐难以实现上述目标。为此,该研究从销售端着手,基于山东省五市十一县的微观调研数据,利用倾向得分匹配和中介模型,考察参与电商对设施蔬菜种植户绿色生产行为的影响。研究发现:①参与电商的设施蔬菜种植户采纳绿色生产行为的概率比非电商户高23.7%,利用工具变量法控制内生性后,该结论依然成立;从参与强度角度讲,高强度参与比低强度参与电商更能提高设施蔬菜种植户的绿色生产水平;从参与模式角度讲,平台电商对设施蔬菜种植户绿色生产行为的提升作用要强于社交电商。②异质性分析发现,作物类别、经营规模和风险偏好会导致影响效应分化,参与电商对根茎类、中等规模、风险偏好型设施蔬菜种植户绿色生产行为的影响效应尤为明显。③机制分析发现,价格预期激励、交易成本节约、信息获取便利、质量信誉评价是参与电商影响设施蔬菜种植户绿色生产行为的中介渠道,中介效应占比依次为20.48%、16.60%、8.28%、10.63%。据此提出:鼓励种植户通过电商渠道售卖设施蔬菜,引导其提高参与电商强度,增加参与模式的多样性;电商推广过程中,要综合考虑作物类别、经营规模、风险偏好等群体异质性特征,制定差异化策略;重点完善绿色设施蔬菜的价格激励机制和交易成本节约机制,拓宽种植户信息获取渠道,密切关注消费者质量评价反馈。 展开更多
关键词 农村电商 绿色生产 设施蔬菜 倾向得分匹配
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北京市设施蔬菜生产分析—基于异质农户的考察
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作者 闫豪玮 穆月英 《中国蔬菜》 北大核心 2024年第2期106-112,共7页
城市郊区蔬菜种植户中外来农户的比重持续增加,农户间“分化”加剧,明确本地农户和外来农户设施蔬菜生产特征,对提高城市的蔬菜应急保供能力意义重大。基于北京市203户农户的调研数据,分析本地农户和外来农户设施蔬菜生产的异质性。结... 城市郊区蔬菜种植户中外来农户的比重持续增加,农户间“分化”加剧,明确本地农户和外来农户设施蔬菜生产特征,对提高城市的蔬菜应急保供能力意义重大。基于北京市203户农户的调研数据,分析本地农户和外来农户设施蔬菜生产的异质性。结果显示:本地农户和外来农户设施蔬菜生产的异质性明显,且表现在三方面。一是要素投入,主要体现在劳动力投入和土地投入,而非资本投入;二是技术推广与采用,主要体现在技术补贴、技术培训以及质量安全型技术采用,而非增产增效型和环境友好型技术采用;三是成本收益,主要体现在雇工费用、地租费用和成本收益率。本地农户技术推广与采用、成本收益高于外来农户,而外来农户的要素投入明显高于本地农户,表明外来农户设施蔬菜生产主要依靠要素投入而非技术采用,进而导致其成本高、收益低。由此,提出对策建议:重视培育新型经营主体、加强财政支持力度以及加快新型技术推广应用,以期破解本地农户和外来农户设施蔬菜生产约束,推动生产能力的全面提升。 展开更多
关键词 设施蔬菜 本地农户 外来农户 异质性
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城市社区养老设施需求识别与空间配置模式——以天津市中心城区为例
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作者 刘奕杉 刘丛红 +1 位作者 杨鸿玮 程坦 《南方建筑》 CSCD 北大核心 2024年第2期94-104,共11页
在完善城市公共服务设施背景下,标准化配置的社区养老设施往往忽略了供需的精准匹配。立足于供需视角,聚焦不同人群特征对需求进行差异化探讨,运用安德森模型和Kano模型展开调研,判断被测群体需求层次和需求程度,通过需求影响因素的相... 在完善城市公共服务设施背景下,标准化配置的社区养老设施往往忽略了供需的精准匹配。立足于供需视角,聚焦不同人群特征对需求进行差异化探讨,运用安德森模型和Kano模型展开调研,判断被测群体需求层次和需求程度,通过需求影响因素的相关性分析和基于需求层次的聚类分析划分人群特征,提取典型群体,分析需求情况。结果表明,人群特征差异和功能空间差异均对需求有显著影响。基于此,分别建立了整体人群和典型人群功能空间配置模型,提出功能独立型社区养老设施配置模式,给出了一套可精准识别需求并合理配置功能空间的方法,为未来社区养老设施设计提供参考。 展开更多
关键词 社区养老设施 空间配置模式 KANO模型 需求层次 需求程度
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我国劳动力价格上升、要素替代与设施蔬菜生产研究——以番茄、黄瓜、茄子和菜椒为例
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作者 钱玮亭 朱彦旭 李梅芳 《中国瓜菜》 CAS 北大核心 2024年第3期184-192,共9页
伴随我国“人口红利”消失,劳动力价格上涨,我国设施蔬菜生产过程中要素投入结构也发生了变化。选取了2011—2020年设施栽培的4种蔬菜作为研究对象,建立超越对数成本份额方程,计算劳动要素的需求价格弹性与劳动力、化肥与农业机械要素... 伴随我国“人口红利”消失,劳动力价格上涨,我国设施蔬菜生产过程中要素投入结构也发生了变化。选取了2011—2020年设施栽培的4种蔬菜作为研究对象,建立超越对数成本份额方程,计算劳动要素的需求价格弹性与劳动力、化肥与农业机械要素之间的需求替代弹性。研究发现,劳动要素需求价格弹性系数为负且绝对值小于1,说明缺乏弹性;机械与劳动和化肥的替代弹性系数大于0且系数值均大于0.5,替代性显著;劳动与化肥弹性系数小于0且绝对值递减接近0,表现为替代性下降,互补性增强。针对研究结论,提出加大设施蔬菜生产的农机购置与农机租赁补贴、加大农机的研发推广力度、推进农艺农机深度融合以及对化肥的使用进行优化等建议。 展开更多
关键词 设施蔬菜 要素禀赋 成本结构 替代弹性
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不同药剂对温室黄瓜根结线虫防效和黄瓜生长的影响
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作者 陈晶 霍柯宇 +2 位作者 杨美玲 王慧林 郭园 《安徽农业科学》 CAS 2024年第1期138-140,共3页
以内蒙古奈曼旗温室黄瓜根结线虫为研究对象,比较了枯草芽孢杆菌、淡紫拟青霉、厚垣轮枝菌及嗜小红卵菌HNI-14种生防药剂及化学药剂噻唑磷对根结线虫的防治效果和对黄瓜植株生长的影响。结果表明,4种生防药剂中淡紫拟青霉对黄瓜根结线... 以内蒙古奈曼旗温室黄瓜根结线虫为研究对象,比较了枯草芽孢杆菌、淡紫拟青霉、厚垣轮枝菌及嗜小红卵菌HNI-14种生防药剂及化学药剂噻唑磷对根结线虫的防治效果和对黄瓜植株生长的影响。结果表明,4种生防药剂中淡紫拟青霉对黄瓜根结线虫防效最好,达76.10%。淡紫拟青霉对黄瓜植株的株高、茎粗、有效叶数、叶面积和根系活力均有促生作用。因此,淡紫拟青霉可推荐为该地区防治蔬菜根结线虫的可替换生防药剂。 展开更多
关键词 设施蔬菜 黄瓜根结线虫 生防药剂 淡紫拟青霉
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