本文采用高效液相色谱法建立了食品中叶黄素、玉米黄质、β-隐黄质同时检测的方法,最终确定最优前处理条件为:试样中加入30 mL含0.1%的2,6-二叔丁基-4-甲基苯酚(BHT)乙醇溶液和10 mL 60%氢氧化钾水溶液,置于恒温水浴箱内50℃振荡皂化15 ...本文采用高效液相色谱法建立了食品中叶黄素、玉米黄质、β-隐黄质同时检测的方法,最终确定最优前处理条件为:试样中加入30 mL含0.1%的2,6-二叔丁基-4-甲基苯酚(BHT)乙醇溶液和10 mL 60%氢氧化钾水溶液,置于恒温水浴箱内50℃振荡皂化15 min,处理样液用100 mL正己烷∶乙醚∶环己烷(2∶2∶1)混合液萃取。结果显示,实验建立的方法提取效果优于国标方法和超声提取方法,可以实现叶黄素的快速温和提取,提取效果较佳。以小米和大米为样品进行方法学验证,结果显示,叶黄素、玉米黄质、β-隐黄质分别在0.2342~9.3689、0.3004~12.0167、0.3734~14.9371μg/mL范围内线性关系良好,平行测定6次,叶黄素、玉米黄质的相对标准偏差(RSD)分别为1.41%、4.98%,小米中未检测到β-隐黄质,加标回收率均在85.6%~98.8%,表明该方法重现行良好、准确可行。该方法的建立可以弥补相关标准的不足,解决实际工作中存在的问题,为产品开发,食物评价和监管提供技术方法。展开更多
Urban green spaces have been arisen growing concern responded to the social and environmental costs of urban sprawl. A wide range of planning and policies has been and/or will be designed to protect urban green spaces...Urban green spaces have been arisen growing concern responded to the social and environmental costs of urban sprawl. A wide range of planning and policies has been and/or will be designed to protect urban green spaces and optimize their spatial pattern. A better design or planning of urban green space can make a major contribution to quality of environment and urban life, and furthermore can decide whether we can have a sustainable development in the urban area. Information about the status quo of urban green spaces can help planners design more effectively. However, how to quantify and capture such information will be the essential question we face. In this paper, to quantify the urban green space, a new method comprising gradient analysis, landscape metrics and GIS was developed through a case of Jinan City. The results demonstrate: 1) the gradient analysis is a valid and reliable instrument to quantify the urban green space spatial pattern precisely; 2) using moving window, explicit landscape metrics were spatially realized. Compared with quantifying metrics in the entire landscape, it would be better to link pattern with process and establish an important basis for analyzing the ecological and socioeconomic functions of green spaces.展开更多
文摘Urban green spaces have been arisen growing concern responded to the social and environmental costs of urban sprawl. A wide range of planning and policies has been and/or will be designed to protect urban green spaces and optimize their spatial pattern. A better design or planning of urban green space can make a major contribution to quality of environment and urban life, and furthermore can decide whether we can have a sustainable development in the urban area. Information about the status quo of urban green spaces can help planners design more effectively. However, how to quantify and capture such information will be the essential question we face. In this paper, to quantify the urban green space, a new method comprising gradient analysis, landscape metrics and GIS was developed through a case of Jinan City. The results demonstrate: 1) the gradient analysis is a valid and reliable instrument to quantify the urban green space spatial pattern precisely; 2) using moving window, explicit landscape metrics were spatially realized. Compared with quantifying metrics in the entire landscape, it would be better to link pattern with process and establish an important basis for analyzing the ecological and socioeconomic functions of green spaces.
