全方位创新重点工程效能监察

要防止重点工程效能监察流于形式并使其真正发挥作用,就必须从制度、体制、工作方法和手段上创新,即实行监督员“派出制”、执行项目经理制度、建立保廉“责任链”并针对监察重点实施阳光探作,以此为提高效能监察和企业管理水平奠定基础。     

4H-SiC MESFET器件工艺

介绍了制作4H-SiC MESFET器件的关键工艺.通过改进工艺,采用半绝缘衬底的国产SiC三层外延片,制造出总栅宽为1mm,2GHz连续波下输出功率大于4W,小信号增益大于10dB的SiC MESFET.     

不同退火温度下Mo/4H-SiC肖特基接触界面特性分析

为研究退火温度对肖特基接触界面特性的影响,在不同温度下测试了不同退火温度处理的Mo/4H-SiC肖特基接触的I-V及C-V特性.根据金属-绝缘层-半导体(MIS)结构二极管模型理论,认为在金属与半导体间存在薄介质层,通过估算介质层电容值,得到了肖特基接触界面态密度(N88)的能级分布情况,N8s约为1012 eV-1·cm-2量级.退火温度升高,N8s的能级分布靠近导带底;测试温度升高,Ns8增加且其能级分布远离导带底.利用X射线光电子能谱(XPS)分析表征肖特基接触界面态化学组分,分析结果证实接触界面存在SiO.SiO组分随退火温度的升高而减少,在退火温度为500℃及以上时检测到Mo-C成分,说明Mo与4H-SiC发生反应.     

Drug Delivery: Bio‐inspired Heterostructured Bead‐on‐String Fibers That Respond to Environmental Wetting (Adv. Funct. Mater. 8/2011)

Inspired by the geometric structure of ecribellate spider capture silk and its spinning characteristics, we propose a one‐step electrohydrodynamic method to fabricate bead‐on‐string heterostructured fibers (BSHFs). By combining electrospinning and electrospraying strategies using a sprayable outer fluid with low viscosity and a spinnable inner fluid with high viscosity in a coaxial jetting process, hydrophilic poly(ethylene glycol) beads are successfully imprinted on a hydrophobic polystyrene string. It is demonstrated that the BSHFs are capable of intelligently responding to environmental change. With a change in relative humidity, the fibers show a segmented swelling and shrinking behavior in the “bead” parts whereas the “string” parts remain the same. The elastic BSHFs with alternating hydrophilic and hydrophobic surface characteristics represent a type of mesoscale analogues that block copolymers and may bring about new properties and applications. Moreover, the combined electrohydrodynamic approach developed herein should open new routes to multifunctional one‐dimensional heterostructured materials.     

DWT based HMM for face recognition

A novel Discrete Wavelet Transform (DWT) based Hidden Markov Module (HMM) for face recognition is presented in this letter. To improve the accuracy of HMM based face recognition algorithm, DWT is used to replace Discrete Cosine Transform (DCT) for observation sequence ex- traction. Extensive experiments are conducted on two public databases and the results show that the proposed method can improve the accuracy significantly, especially when the face database is large and only few training images are available.     

机载SAR系统平台运动容差分配方法

合成孔径雷达(SAR)系统平台运动容差分配是系统要求分配的一个重要方面,它是系统设计中的必要步骤,通过考虑误差源、误差影响和性能极限等因素使得最终的设计方案更为合理。该文在分析和仿真平台运动误差对SAR成像质量的影响的基础上,提出了一种机载SAR系统平台运动容差分配的方法:根据实际成像系统和成像环境搭建仿真平台后,通过仿真实验逐步得到独立运动误差容限、联合运动误差容限和修正运动误差容限,最后考虑一些相关因素在前面仿真所得的容限区域上合理地做出平台运动容差分配的最后决策。这种方法将系统的平台参数、平台运动误差的类型和方向、测绘宽度以及成像质量要求等因素均作为分配过程的约束条件,是一种兼具针对性和合理性的SAR系统平台运动容差分配方法。     

一种基于混沌的真随机源电路

提出了一种基于混沌的随机源电路,通过利用电容上电荷的再分配,实现了一个离散混沌系统.该电路在0 .8μm CMOS工艺下流片成功,核心面积小于4 2 0 0 μm2 ,功耗小于1m W,优于目前已有的几种实现方法.     

ZnLiFeO_3高温热敏厚膜材料的研究

ＺｎＬｉＦｅＯ３（ＺＬＦ）高温ＮＴＣ热敏厚膜材料，是以尖晶石结构的ＺｎＬｉＦｅＯ３导电陶瓷作厚膜浆料的导电相，以Ａｌ２Ｏ３瓷为基体，用厚膜工艺制成的。实验表明，在氮气中烧结的ＺＬＦ厚膜材料，室温方阻１０３Ω／□级，Ｂ值约１０００Ｋ。在高温５００～７００℃范围内，方阻降为１０２Ω／□级，Ｂ值仍小于１０００Ｋ。是一种很有前途的高温热敏材料。     

Calculation of the Figure of Merit of Linearly Chirped Fiber Gratings for Dispersion Compensation

1IntroductionBecauseoftheadventoferbium-dopedamplifiers,thelengthoftheophcalfiberlinksisnolongerlicitedbytheabsorphon,butratherbythechromaticdispersionofthefiber.Especially'theophcalsignalshapeissoseriouslydestroyedthatthebit-error-rate(BER)isratherhigherinthelonghaulhigh-bit-rateophcalcommunicationsystem.Sothedispersionoffibermustbecompensatedbyvariouskindsofdevices.Amongthem,thecompensatorusingthelinearlychirpedfibergratingshascausedagreatinterestindispersioncompensatingdeVices11-5].Onemus…     

Mg17 Al12、Al2Ca、Al2Nd、Al2Er金属间化合物稳定性与电子结构的第一性原理研究

采用基于密度泛函理论的Castep程序软件包,优化了Mg17Al12、Al2Nd、Al2Er及Al2Ca相晶胞结构,计算了化合物的形成热、结合能和态密度等,分析了化合物结构稳定性与其电子结构的内在联系。结果表明:四种化合物的形成热和结合能均为负值,且化合物的合金化能力和结构稳定性强弱顺序依次为Al2Er、Al2Nd、Al2Ca、Mg17Al12。态密度结果表明: Al2Er和Al2Nd具有较强结构稳定性的主要原因是（1）在费米面低能级区Al(3p)轨道分别与Nd(4f)、(5d)和 Er(4f)、(5d)轨道价电子发生强烈杂化作用;（2）Al2Nd和Al2Er成键电子数较多;（3）这两种化合物的电子参与成键能力较大。电荷密度结果表明：Mg17Al12、Al2Ca、Al2Nd、Al2Er中均存在金属键、离子键、共价键,四种化合物中Al2Er、Al2Nd共价键较强,Al2Ca离子键最强,Mg17Al12中以较强的金属键为主。