Asymmetric Soft-Structure Functional Surface for Intelligent Liquids’ Distinction,Transportation, and Reaction Mixer

Structured surfaces have attracted wide attention because of their great potential in directional transport, liquid collection or separation, microfluidics, etc. However, it remains a big challenge to design a surface that can distinguish various liquids, utilize their inherent properties to control their transportation, and realize functional applications. Herein, it is presented an asymmetric soft-structure functional surface (ASFS) with arrayed curvature units that can make the Laplace pressure as a driving force to determine the preferential spreading direction and show abundant transport behaviors for liquids with different surface tensions. With good deformability, the proposed ASFS can directionally transport liquids along complex terrains, e.g., 1D-tilted, 2D-curved, and 3D-helical trajectories. It is also demonstrated that the ASFS can achieve synchronous or asynchronous liquid mixing by choosing appropriate liquids. Moreover, the intelligent response ability allows the ASFS to be a portable contact angle discriminator. This study proposes a new strategy to manipulate liquids via their intrinsic properties and opens new avenues for application-oriented liquid operation surfaces.     

Matched Filter Based Spectrum Sensing When Primary User Has Multiple Power Levels

In this paper,we investigate the matched filter based spectrum sensing in a more reasonable cognitive radio(CR) scenario when the primary user(PU) has more than one transmit power levels,as regulated in most standards,i.e.,IEEE 802.11 Series,GSM,LTE,LTE-A,etc.This new multiple primary transmit power(MPTP) scenario is specialized by two different targets:detecting the presence of PU and identifying the power level.Compared to the traditional binary sensing where only the presence of PU is checked,SU may attain more information about the primary network(making CR more intelligent) and design the subsequent optimization strategy.The key technology is the multiple hypothesis testing as opposed to the traditional binary hypothesis testing.We discuss two situations under whether the channel phase is known or not,and we derive the closed form solutions for decision regions and several performance metrics,from which some interesting phenomenons are observed and the related discussions are presented.Numerical examples are provided to corroborate the proposed studies.     

Broadcast-First Service Scheduling Scheme for Vehicle-Roadside Communication

In recent years, the research of vehicular ad-hoc networks (VANET) has become increasingly popular. More and more vehicles want their requests to be served from roadside units (RSU) in VANET, thus the service scheduling of RSU becomes an important task, especially when a large number of vehicles drive past the RSU and access data. Obviously, different kinds of request messages have different degrees of emergency, in other words, request messages have different priorities while scheduling. In order to provide a more effective and appropriate scheme, in this paper we study the scheduling of service algorithm in VANET, and proposed a novel broadcast-first service scheduling scheme. That scheme is on the basis of existing priority schemes, and takes channel bandwidth and processing capability of RSU into consideration so as to cope with the challenges in vehicle-roadside data access. Finally we conduct our experimental scenario, and simulation results show that our algorithm performs better than other existing algorithms by the comparison.     

Room-Temperature Metal-Catalyzed Ultrafast Gasification of Ultrathin Boron Flakes

The trivalent outer shell of boron renders this element electron-poor but chemically rich, exhibiting more than one dozen allotropes. Its 2D polymorph has been recently synthesized on metal substrates under ultrahigh vacuum and has attracted intense interest. However, probing its properties ex situ has been challenging due to the quality degradation—surface oxidation—that occurs upon exposure to ambient environments. Herein, this surface chemistry is investigated in regard to the air stability of ultrathin boron flakes on metals prepared by atmospheric-pressure chemical vapor deposition. The characteristic Volmer–Weber growth is recognized by the stacking of polygon-shaped, thin flakes as isolated islands. Significantly, the metal-catalyzed, ultrafast gasification of boron flakes at room temperature, exemplified by the complete, spontaneous vanishment of 200 nm-thick boron islands in 3 h is observed. A two-step mechanism, first oxygen-involved surface oxidation and then subsequent reactions with water forming a highly volatile boric acid layer, is unambiguously revealed by combined surface characterizations. The catalysis by metal substrates, corroborated by theoretical calculations, is attributed as the crucial cause of the unprecedented gasification. The concept of oxygen-free growth is thereby proposed for air-sensitive material growth by introducing in situ oxygen scavengers. These findings significantly expand the fundamental understanding of the surface chemistry of boron and pave the way for the chemical vapor deposition growth of hydrophobic materials.     

CuI Encapsulated within Single-Walled Carbon Nanotube Networks with High Current Carrying Capacity and Excellent Conductivity

High current carrying capacity and high conductivity are two important indicators for materials used in microscale electronics and inverters. However, it is challenging to obtain high conductivity and high current carrying capacity at the same time since high conductivity requires a weakly bonded system to provide free electrons, while high current carrying capacity requires a strongly bonded system. In this paper, CuI@SWCNT networks by filling the single-walled carbon nanotubes (SWCNTs) with CuI is ingeniously prepared. CuI@SWCNT shows good stability due to the confinement protection of SWCNTs. Through the host-guest hybridization, CuI@SWCNT networks exhibit a current carrying capacity of 2.04 × 10⁷ A cm⁻² and a conductivity of 31.67 kS m⁻¹. Their current carrying capacity and conductivity are significantly improved compared with SWCNT. The Kelvin probe force microscopy measurements show a drop of surface potential energy after SWCNT filled with CuI, indicating that the CuI guest molecules regulate the position of the Fermi level of SWCNTs, increasing carrier concentration, achieving high conductivity and high current carrying capacity. This study offers ideas and solutions for the regulation of high-performance carbon tube networks, which hold great promise for future applications in carbon-based electronic devices.     

基于InP/InGaAs HBT技术的单片集成长波长光接收OEIC

采用InP/InGaAs HBT与PIN光探测器单片集成方案,对光接收光电集成电路(OEIC)的外延材料结构和生长、电路设计、制作工艺和性能测试进行了研究.基于自对准InP/InGaAs HBT工艺,实现了1.55μm波长单片集成光接收OEIC.发射极尺寸2μm×8μm的InP/InGaAs HBT直流增益为40,截止频率和最高振荡频率分别为45和54GHz;集成InGaAs PIN光探测器在-5V下响应度为0.45A/W@1.55/μm,暗电流小于10nA,-3dB带宽达到10.6GHz;研制的HBT/PIN单片集成光接收OEIC在2.5和3.0Gb/s速率非归零223-1伪随机码传输工作时可以观察到张开的眼图,灵敏度≤-15.2dBm@BER=10-9.     

业务应用--3G成功的决定因素

欧、亚、美等通信发达地区已经开始发展3G商用网络。目前用户享受到的3G网络包括简单话音／消息、多蝶体信息、定位、移动互联网、高级话音等业务。用户关心的热点业务包括多媒体短信、定位、可视电话、移动电子商务、移动游戏等业务。内容更丰富、服务更贴近生活、地域服务差异性成为3G业务的发展方向，     

硅基高长径比微孔列阵及其应用

介绍了硅基高长径比微孔列阵形成的多路感应耦合等离子体刻蚀和电化学刻蚀等半导体工艺技术,给出了实验系统、原理、方法和实验结果,指出了工艺中出现的新现象和亟待解决的新问题,阐述了其在二维通道电子倍增器-微通道板中的应用。     

分子组装偶氮苯衍生物Langmuir-Blodgett膜热释电性能的研究

利用Langmuir-Blodgett方法对偶氮苯衍生物进行了极性分子组装.测得了静态和动态热释电活性和频率响应.30个单分子层LB膜的热释电系数在室温下达到7μCm~(-2)K~(-1).利用FTIR线性二向色性光谱研究了分子轴和几个主要的极性极团的跃迁矩方向和分子在LB膜中的结构.讨论了这种极化取向对热释电活性的影响.     

红外光谱辐射计的研制

介绍了红外光谱辐射计的组成及工作原理,分析了其信号处理方法。红外光谱辐射计的核心是分光元件、光学系统及信号处理部分。该设备采用容易调整的高像质反射光学系统和波长在２５～１４μｍ连续可变的分光系统,并采用高集成度、高精度的数据采集、数字锁相和数据处理、存储系统。观察瞄准、探测接收的光学系统以及数据采集、处理系统都被放到一个体积很小的测量头中,具有体积小、质量轻牢固可靠、抗干扰性能强和使用方便等优点。入瞳的最小可探测率为１０－１２Ｗ／ｃｍ２,光谱分辨率为２％,测量速度为１０条谱线／ｓ。经实际检测和使用,该设备的性能达到国内外先进水平,并具有野外工作的特点。