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81.
82.
This paper presents an integration technology for RF passives using benzocyclobutene (BCB)/metal multilayer interconnection
for system-in-package applications. This technology has been specially developed for RF subsystem packages in which a thick
polymer, BCB (more than 15 μm thick), is adopted as dielectric with lossy silicon as substrate for its excellent characteristics.
Both dry-etch BCB and photosensitive BCB are applied in this work, and their processes are briefly introduced and compared.
An RF power divider, an MIM capacitor, different types of RF inductors as well as a coupled microstrip based band-pass filter
are fabricated and measured at wafer level. The results show good electrical performances, and accordingly the passives are
well applicable in RF band. Moreover, the subsystem models including monolithic chips connected with passives are presented. 相似文献
83.
Spatial and temporal variations in algal blooms in the coastal waters of the western South China Sea
Algal blooms occur frequently in the coastal waters of the western South China Sea (SCS). This paper reports spatial and temporal variations of algal bloom events in these waters from 1993 to 2007. Twenty-five algal bloom events occurred in summer in the coastal waters of South and Central Vietnam where they were associated with wind-induced, coastal, nutrient upwelling and river discharges; a further eight events occurred in the coastal waters of North Vietnam. A greater number of algal bloom events were observed in 1999 and 2002, and were accompanied by several previously unobserved species for the study period. These events may be related to the El Niño events of 1998 and 2002. Furthermore, the bloom-causative species Trichodesmium erythraeum (Cyanophyta) entirely dominated the phytoplankton community of algal blooms during 1993–1999 whereas the species Phaeocystis globosa (Haptophyta) dominated blooms after 2002. This study establishes a basis for further long-term research of algal bloom event variations, and provides a compiled scientific reference that may be used for later prediction of Harmful algal blooms (HABs). 相似文献
84.
一直以来,日本高度重视污泥的资源化利用,并将考核指标更改为生物质循环利用率,同时对下水道重新定义,这对今后日本污泥处理处置的技术路线产生很大的影响.在介绍日本污泥处理处置现状的基础上,重点介绍在日本广泛应用的回转式污泥干化和焚烧装置.日本污泥处理处置的思路、经验和相关设备对我国污泥处理处置技术路线的选择和干化焚烧设备选择有较好的借鉴意义. 相似文献
85.
86.
设计制作基于433.9MHz业余频段的绿色无线节能控制器,实现了通过同步个人电脑(PC)或者服务器的开、关机行为,远程无线控制路由器供电插座的开关,使路由器在不使用的时间处于断电状态.此控制器有发射板与接收板两个部分.控制器的接收部分功耗低于1 W,降低能耗同时减少了空间电磁辐射.发射部分则利用摩托车防盗的电路技术,保证信号稳定性,其有效范围在200m左右.并利用芯片PT2262/2272远程的编码、解码功能屏蔽了干扰.一旦控制器的发射部分接受供电,就能立刻唤醒路由器,在很大程度上节约了电能. 相似文献
87.
Recently, there has been a dramatic increase in research on data mining on social networks and social media. Theubiquitous nature of Web-enabled devices, including desktops, 相似文献
88.
FeTiO3 powder was prepared via a liquid mix and H2/H2O reduction process. First, an intermediate compound was synthesized by a liquid mix process. This precursor compound to FeTiO3 was characterized by thermal analysis (TG/DTA) and Fourier Transform Infrared spectroscopy (FT-IR). Second, the precursor was annealed in the air, H2/H2O(g) mixing gas stream, respectively. The obtained powder was characterized by X-ray diffraction (XRD), energy dispersive X-ray analysis spectroscopy (EDAX) and scanning electron microscope (SEM). It was showed that pure and homogenous FeTiO3 was successfully obtained below 600 °C. 相似文献
89.
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