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991.
María del Rocío Gómez-García Neftalí Ochoa-Alejo 《International journal of molecular sciences》2013,14(9):19025-19053
Capsicum species produce fruits that synthesize and accumulate carotenoid pigments, which are responsible for the fruits’ yellow, orange and red colors. Chili peppers have been used as an experimental model for studying the biochemical and molecular aspects of carotenoid biosynthesis. Most reports refer to the characterization of carotenoids and content determination in chili pepper fruits from different species, cultivars, varieties or genotypes. The types and levels of carotenoids differ between different chili pepper fruits, and they are also influenced by environmental conditions. Yellow-orange colors of chili pepper fruits are mainly due to the accumulation of α- and β-carotene, zeaxanthin, lutein and β-cryptoxanthin. Carotenoids such as capsanthin, capsorubin and capsanthin-5,6-epoxide confer the red colors. Chromoplasts are the sites of carotenoid pigment synthesis and storage. According to the most accepted theory, the synthesis of carotenoids in chili peppers is controlled by three loci: c1, c2 and y. Several enzymes participating in carotenoid biosynthesis in chili pepper fruits have been isolated and characterized, and the corresponding gene sequences have been reported. However, there is currently limited information on the molecular mechanisms that regulate this biosynthetic pathway. Approaches to gain more knowledge of the regulation of carotenoid biosynthesis are discussed. 相似文献
992.
993.
This study draws upon concepts in landscape research and environmental justice to examine the association between community poverty and environmental violations that occurred between 2002 and 2008 across 110 coal strip mining operations located within the United States. Multivariate results suggest that residential poverty is greater around facilities that have been identified as violating an environmental law. In addition, the association between poverty and violations is dependent upon regulatory inspections. While an increase in inspections is associated with an increase in the odds that a violation will be discovered, it is also associated with lower levels of community poverty. We conclude that this pattern of associations between poverty, inspections, and violations is consistent with arguments in the environmental justice and landscape literatures. 相似文献
994.
浅谈水泵的节能技术改造 总被引:2,自引:0,他引:2
水泵是企业中使用最普遍的设备之一,当前企业使用的水泵还普遍存在着效率偏低及运行成本较高的问题。本分析了制约水泵效率的因素,提出了挖掘水泵节能降耗的途径。 相似文献
995.
状态观测器及状态反馈控制在亚临界锅炉蒸汽温度控制系统中的应用 总被引:32,自引:15,他引:17
提出了一种将状态反馈与PID 控制相结合的控制方案,既克服了PID 对大滞后对象控制效果不理想的缺点,同时又具有在目前的DCS系统中易于实现的优点。该控制方案应用于一台1025t/h 的亚临界锅炉蒸汽温度控制系统中,取得了将偏差控制在不超过±2℃范围内的优良效果。 相似文献
996.
997.
低温早期受冻引起的混凝土结构破坏严重,混凝土强度无法达到设计的强度要求.对低温季节里混凝土受冻破坏机理进行了分析,强调了混凝土早期防冻的必要性,并提出了有效的防冻措施. 相似文献
998.
999.
Challenges and opportunities in watershed management for Laguna de Bay (Philippines) 总被引:2,自引:0,他引:2
M. T. T. Oledan 《Lakes & Reservoirs: Research and Management》2001,6(3):243-246
Laguna de Bay is the largest lake in the Philippines and the second largest freshwater lake in South‐East Asia. The lake is shallow with a mean depth of only 2.8 m. Rice paddies, sugar cane fields, coconut plantations and other agricultural fields make up large portions of the catchment area, although there is also extensive urbanization and industrialization. As industry and population around the lake have grown, the lake and its tributaries have become overwhelmed by industrial, commercial, agricultural and domestic pollution resulting in massive fish kills and polluted water. Laguna de Bay is under the management and protection of a national government agency known as Laguna Lake Development Authority (LLDA). In 1983, the LLDA was given the power to control and abate pollution within the Laguna de Bay watershed. The mandate of the LLDA includes the environmental regeneration and sustainable development and use of the lake’s waters, fisheries and wetlands. The LLDA receives no federal funds but it retains and uses collected fees from regulated industries. The LLDA has instituted an environmental‐user fee or pollution‐charge system that has given corporations an incentive to construct and use wastewater treatment plants at a lower cost than the required fees for dumping waste into Laguna de Bay. User fees provide more flexibility about how and when a user or industrial facility cleans up its manufacturing process. Many medium‐ and large‐sized domestic and multinational corporations have achieved at least 30–50% reductions in pollution loads. The user fees also encourage industry water conservation. Other creative approaches to conserving Laguna de Bay include ‘Environmental Armies’ that consist of volunteers who clean up river banks, demolish illegal fish pens and install low‐cost garbage traps at the river’s mouth. ‘Poison Awards’ are given annually and publicly to companies that continue to dump large amounts of waste into lake tributaries. Organizers also name a ‘Most Improved Company’ to provide a positive incentive. Laguna de Bay stakeholders face a severe shortage of resources to continue their work. Innovative strategies are needed to achieve pollution reductions from smaller industries 相似文献