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101.
厘清国土空间规划管制与区域经济协调发展之间的关系,是我国国土空间规划管制有效开展的重要前提。论文主要结合国内外最新的实证研究文献,在国土空间规划管制对区域经济协调发展影响的“表现形式—作用机理—协调机制”这一逻辑框架下,分析了国土空间规划管制与区域经济协调发展的关联机理。研究结果表明:1)国土空间规划管制影响区域经济协调发展主要表现在发展受限制区域的土地产权受到抑制和资源环境保护的外部性未能有效地内在化;2)国土空间规划管制影响区域经济协调发展的作用机制在于保护型区域生产的生态产品可贸易性较差,使其落入比较优势陷阱;3)国土空间规划管制下的区域经济协调机制主要包括土地发展权漂移、税费调节和地役权保护。从理论和实践上来看,空间规划管制从诞生起,就面临效率的争议,但在资源环境保护的巨大压力之下,国土空间规划管制在实践层面又非不可调和,关键在于区域经济协调机制的设计。这对我国在建立“多规合一”的国土空间规划体系的时代背景下,为避免新的区域经济协调发展问题具有重要的政策含义。  相似文献   
102.
应用气相色谱法测定海水中氯氟烃,海水用Niskin采水器采集,将海水转移玻璃注射器中储藏直到分析。把大约30mL海水引入到一个玻璃气提器中,用高纯氮气将溶解在海水中氯氟烃(CFC's)吹扫出来浓缩在冷捕集器中,然后把捕集器加热,用高纯氮气CFC's送入气相色谱分离柱,CFC's由电子捕获检测器(ECD)检测出。结果表明:该方法快速,灵敏度高,分离效果好,适用于分析测定水体中氯氟烃。  相似文献   
103.
Abstract:  The emerging world crisis created by declining fish stocks poses a challenge to resource users and managers. The problem is particularly acute in poor nations, such as those in East Africa, where fishing is an important subsistence activity but high fishing intensity and use of destructive gear have resulted in declining catches. In this context developing effective management strategies requires an understanding of how fishers may respond to declines in catch. We examined the readiness of 141 Kenyan fishers to stop fishing under hypothetical scenarios of declines in catch and how socioeconomic conditions influenced their decisions. As expected, the proportion of fishers that would exit the fishery increased with magnitude of decline in catch. Fishers were more likely to say they would stop fishing if they were from households that had a higher material style of life and a greater number of occupations. Variables such as capital investment in the fishery and the proportion of catch sold had weak, nonsignificant relationships. Our finding that fishers from poorer households would be less likely to exit a severely declining fishery is consistent with the literature on poverty traps, which suggests the poor are unable to mobilize the necessary resources to overcome either shocks or chronic low-income situations and consequently may remain in poverty. This finding supports the proposition that wealth generation and employment opportunities directed at the poorest fishers may help reduce fishing effort on overexploited fisheries, but successful interventions such as these will require an understanding of the socioeconomic context in which fishers operate.  相似文献   
104.
燃煤电厂排放总气态汞连续自动监测技术的选择   总被引:1,自引:0,他引:1  
介绍了汞连续排放监测系统和汞吸附管采样系统的主要特点,比较了不同仪器的测定原理、样品处理技术、检出限和测定汞的形态,报道了美国环境保护署认证中心关于两个系统的认证结果.建议将汞连续排放监测系统与汞吸附管监测系统两种技术联合用于我国燃煤电厂排放总气态汞的自动监测.  相似文献   
105.
利用吹扫捕集-GC/MS法对引起南宁市竹排冲河道水体黑臭的嗅味物质进行检测分析。结果表明,导致竹排冲水体黑臭的嗅味物质主要为苯系物、硫类化合物和氯苯类化合物,其中甲硫醚(相对含量1.70%)、二甲基二硫醚(相对含量3.19%)、甲基丙基二硫醚(相对含量6.11%)等挥发性有机物为竹排冲水体中的主要致嗅物质,是竹排冲水体嗅味产生的主要原因。  相似文献   
106.
柴油机机外净化技术发展现状及展望   总被引:3,自引:2,他引:1  
汽车柴油化已成为一个国际趋势,柴油机的气体净化得到越来越多的关注,面对欧洲Ⅳ/Ⅴ排放标准,开发适用于高标准的排放控制技术成为迫切需要解决的问题,而机外净化是这一技术的关键。对当前国内外研究和应用较多的柴油机机外净化技术进行了综述,分析了各种方法的原理、特点、处理效果及应用前景,并对其发展的趋势进行了展望。  相似文献   
107.
An extensive study on the presence of illicit drugs and pharmaceuticals with potential for abuse in sewage waters was made for the first time in the Netherlands. A total number of 24 target drugs were investigated in influent and effluent wastewater using liquid chromatography coupled to a high resolution Orbitrap mass spectrometer. This powerful analyzer has allowed not only the detection and identification of the compounds under investigation, but also their quantification at very low levels, which is highly innovative in the field of drugs of abuse. Samples were taken from five sewage treatment plants (STPs) during a whole week. The selected STPs served four cities of different size and an international airport. Daily variances of drug loads were demonstrated and removal efficiencies calculated for each drug and STP individually. Twelve target compounds were found in at least one influent or effluent, and highest concentrations were observed in influents collected from more urbanized areas. The compounds more frequently detected were amphetamine, benzoylecgonine, cocaine and THCCOOH together with the pharmaceuticals codeine, oxazepam and temazepam. Established week trends in consumption of drugs showed distinct differences between individual drugs. A slightly different occurrence pattern was observed in wastewaters from the airport. Thus, methamphetamine was only detected at Schiphol, a fact that was interpreted to be caused by consumption of this drug by travelers. Despite the fact that the Netherlands has frequently been criticized for its liberal drug policy the results from this study did not reveal higher drug consumption than found elsewhere, with the exception of cannabis.  相似文献   
108.
Seven polycyclic aromatic hydrocarbons (PAHs) in atmospheric particulates were determinated by high performance liquid chromatography (HPLC) with fluorescence detector using direction injection and an on-line enrichment trap column.The method simplified the sample pretreatment,saved time and increased the efficiency.With the on-line trap column,PAHs were separated availably even underground injecting 1.0 ml sample with relatively high column efficiency.The recoveries of the seven PAHs were from 85% to 120% for spiked atmospheric particulate sample.The limit of detection was 15.3-39.6 ng/L (S/N=3.3).There were good linear correlations between the peak areas and concentrations of the seven kinds of PAHs in the range of 1-50 ng/ml with the correlation coefficients over 0.9970.Furthermore,it also indicated that the method is available to determine PAHs in atmospheric particulates well.  相似文献   
109.
屠宰废水处理工程实践与工艺探讨   总被引:1,自引:0,他引:1  
屠宰废水具有有机物浓度高、杂质和悬浮物多、油脂浓度高等特点,采用隔油沉淀-气浮-UASB-接触氧化的主体处理工艺对屠宰废水进行处理,取得了较好的处理效果,出水达到GB 13457—92《肉类加工工业水污染物排放标准》的二级排放标准。  相似文献   
110.
Understanding and modelling insect pest dispersal is an important prerequisite for designing integrated pest management programs. Nevertheless, studies investigating the dispersal of small insects in natural conditions remain scarce mainly because of the difficulty of tracking the movements of these organisms. Here we propose to use Hierarchical Bayesian Modelling (HBM) framework to gain knowledge on hidden processes that cannot be observed directly in natura, such as insect landing and insect mortality, through the definition of latent variables. An HBM describing crop colonization by winged aphids was fitted to a large dataset of field observations issued from a long term survey at a wide scale of both aerial and field densities of the bird cherry-oat aphid Rhopalosiphum padi. This study provides the first evidence that suction trap data are reliable proxies of aphid colonizing rates in cereal fields in autumn and can be a nice alternative to the very time-consuming crop sampling. The proportion of winged aphids landing in cereal fields is shown to vary between regions according to the degree of investment of local R. padi population in sexual reproduction. Results also indicate that under autumnal field conditions, less than 5% of winged aphids survive more than 10 days after landing. This HBM provides the basis of a predictive model for aphid crop colonization that fully accounts for all sources of uncertainty. It should be of great value to improve the trust of users in any decision making systems.  相似文献   
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