| 3 | Invaders’ control on post-disturbance succession in coastal mangroves显示文摘Aims In recent years,coastal mangroves have been frequently affected by large disturbances(cyclones,hurricanes,flooding and tsunamis)and post-disturbance vegetation is often dominated by small stature mangrove,mangrove-associate and non-mangrove species potentially affecting ecosystem functioning.Knowledge on the processes of mangrove vegetation development and recovery(succession)following normal and large disturbances will benefit practitioners in designing robust ecosystem management/restoration plans.Here we propose a conceptual model of disturbance-mediated succession in mangroves.Methods Based on field observations and species’life history traits,we develop conceptual models of mangrove succession under normal disturbance regime and recently experienced increased frequency of large disturbances.We evaluate our conceptual models by conducting a scenario testing experiment.Important Findings We suggest two predominant processes affecting mangrove succession after disturbance:propagule limitation due to damage of seed producing mature trees and dispersal barrier resulting from biological invasion associated with large disturbance.We argue that large disturbances affect mature trees more than the small-stature non-tree(shrubs,herbs and climbers)species creating a larger propagule shortage for mangrove tree species than non-tree species.Secondly,large disturbances facilitate invasion of free-floating aquatics,which may interfere with the flow-facilitated propagule dispersal and seedling establishment of mangrove species.In a scenario testing experiment,we have shown that similar levels of disturbance impact vegetation development and recovery differently depending on the presence or absence of invasive species.We conclude that since biological invasion is one of the major drivers of post-disturbance mangrove succession,the dimension of biological invasion should be included in prediction,management and restoration of mangrove forests. | Shekhar R.Biswas Md.Saiful Islam Khan Azim U.Mallik | 2012 | Journal of Plant Ecology2012，5，2： | 0 |
| 4 | 模压混合集成电路封装技术显示文摘AT&T公司在开关、信号传输产品中大量使用了混合集成电路,以提高集成度和可靠性,简化大系统的组装和测试。AT&T公司的新系统产品将采用一些I/O接头比现行设计多得多的混合集成电路,这些电路主要采用表面组装形式封装。我们正在为这些新的混合IC应用开发符合JEDEC标准的塑封系列产品。我们提供的混合IC在封装的外形和性能上都与分立IC相同,希望我们的用户能得到较大的好处。由于可用一些标准CAD库来确定部件布位、布线、焊接点尺寸和封装的电气特性,因此、系统设计可得到简化。由于可用工业标准设备进行电气测试、元件安放、回流焊、清洗和检查,因此可提高工艺性。总之,整个系统的可靠性得到了提高,因为在制造电路板时使用了标准元件、设备和优化工艺。AT&T公司还研究了68和124引线、1.27mm间距和132引线、635um间距的四方形封装的机械可靠性。结果表明,这三种封装都能承受几百次-40℃~+130℃的温度循环试验,而机械性能没有下降。目前正在做进一步的工作,就这些封装在厚薄膜金属化、厚薄膜、电阻、CBIC和CMOS丝焊IC、芯片电容和电阻、厚膜穿接、多层聚合物介质等方面进行全面考核。 | R.Biswas 武俊齐 | 1991 | 微电子学1991，21，3： | 0 |
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