成都市生活垃圾分类支付意愿及影响因素的问卷调查分析

为了为成都市垃圾分类政策制定提供科学依据,文章基于问卷调研,运用条件价值评估法结合二元Logistic回归模型、多元线性回归模型,分析了成都市居民对城市生活垃圾分类的支付意愿(WTP)及其影响因素。调研发现:问卷填报者中95.3%的人支持强制垃圾分类,但仅21.0%人深入掌握垃圾分类知识;造成成都市垃圾分类失效的原因,73.8%的人认为政策不到位,需要采取强制监管措施,67.6%的人认为垃圾分类桶等基础硬件设施建设不到位,69.2%的人认为居民自身环保意识差,需要加强环保宣传教育。成都市居民生活垃圾治理的WTP金额为12.65元/月/户。年龄、有无住房、户口类型和月收入4个因素对支付额度有显著影响。     

A new method for spectrophotometric determination of benzene in air

A new spectrophotometric method for the determination of benzene in air is described. The method is based upon the nitration of benzene to m-dinitrobenzene and subsequent reduction to m-phenylenediamine. m-Phenylenediamine is determined by diazotization-coupling reaction. α-Naphthol is used as a coupling reagent. Beer's law is obeyed in the range of 10–80 μg of m-dinitribenzene per 25 mL sample. The dye shows a wavelength of maximum absorption at 530 nm. The dye is stable for ～ 30 h. Toluene, the major interferent, can be separated. Beer's law, sensitivity, reproducibility, and other reaction conditions such as time, temperature, and acidity were studied. Formation of stable dye is the main advantage of the method over the butanone method for benzene, in which the colored complex is stable for only 5 min. It is possible to determine traces of benzene (0.05–0.30 μg/mL) by extracting the azo dye in 10 mL iso-amyl alcohol; this also increases the stability of the dye up to 42 h.     

Is there a commercially viable market for crop insurance in rural Bangladesh?

The study aims to assess the commercial viability of a potential crop insurance market in Bangladesh. In a large scale household survey, agricultural farm households were asked for their preferences for a hypothetical crop insurance scheme using double bounded (DB) contingent valuation (CV) method. Both revenue and production cost based indemnity payment approaches were applied to assess the commercial viability of a crop insurance program assuming a partner-agent (PA) model of insurance supply. Crop insurance is found marginally commercially viable in riverine flood plain areas. The expected indemnity payable consistently exceeds the expected insurance premium receivable by the insurer for the households living in wetland basin and coastal floodplain. We conclude that a uniform structure of crop insurance market does not exist in Bangladesh. The nature of the disaster risks faced by the farm households and the socio-economic characteristics of the rural farm communities need to be taken into careful consideration while designing such an insurance scheme.

长江流域南京段河流非使用价值评估

采用逻辑回归与相关性分析法,探讨影响公众支付意愿的因素及其影响程度。结果表明,政府信任度、个人经济收入、年龄和环保意识4个变量因子对支付与否具有显著影响;受教育程度和环保意识这两个变量因子对支付意愿的高低具有显著影响。