SiON对Si基SiO_2AWG偏振补偿的数值分析

采用全矢量交替方向隐含迭代方法系统分析了高折射率 Si ON薄膜对 Si基 Si O2 阵列波导光栅中波导应力双折射的影响 .分析结果表明在芯区上或下表面沉积 Si ON薄膜可以明显减小 Si基 Si O2 阵列波导光栅 (AWG)中波导的应力双折射 ,但这两种补偿方法容易使模场偏移中心位置 ,不利于波导与光纤的耦合 .理想的补偿方法是在芯区上下同时补偿 ,可减小模场偏移 ,并用该方法设计了偏振无关的 1 6通道 AWG.

White organic light-emitting diodes based on a combined electromer and monomer emission in doubly-doped polymers

We report on white organic light-emitting diodes （WOLEDs） based on polyvinylcarbazole （PVK） doped with 1,1-bis（（di-4-tolylamino）phenyl）cyclohexane （TAPC） and perylene, and investigate the luminescence mechanism of the devices. The chromaticity of light emission can be tuned by adjusting the concentration of the dopants. White light with the Commission Internationale de L＇Eclairage （CIE） coordinates of （0.33, 0.34） is achieved by mixing the yellow electromer emission of TAPC and the blue monomer emission of perylene from the device ITO/PVK： TAPC： perylene （100：9：1 in wt.） （100 nm）/tris-（8-hydroxyquinoline aluminum （Alq3） （10 nm）/A1. The device exhibits a maximal luminance of 3727 cd/m2 and a current efficiency of 2 cd/A.

Hippocampal gene expression in a rat model of depression after electroacupuncture at the Baihui and Yintang acupoints

Preliminary basic research and clinical findings have demonstrated that electroacupuncture ther- apy exhibits positive effects in ameliorating depression. However, most studies of the underlying mechanism are at the single gene level; there are few reports regarding the mechanism at the whole-genome level. Using a rat genomic gene-chip, we profiled hippocampal gene expression changes in rats after electroacupuncture therapy. Electroacupuncture therapy alleviated depres- sion-related manifestations in the model rats. Using gene-chip analysis, we demonstrated that electroacupuncture at Baihui （DU20） and Yintang （EX-HN3） regulates the expression of 21 genes. Real-time PCR showed that the genes Vgf, lgf2, Trnp32, Loc500373, Hifla, Folrl, Nrnb, and Rtn were upregulated or downregulated in depression and that their expression tended to nor- malize after electroacupuncture therapy. These results indicate that electroacupuncture at Baihui and Yintang modulates depression by regulating the expression of particular genes.

聚合物SiON波导的可变光衰减器性能研究

利用弯曲聚合物SiON波导设计了一种新型可变光衰减器,该器件由输入、输出直波导,S型的弯曲波导,以及在聚合物SiON波导弯曲部位镀上的电极组成.通过外加电场的作用来调节波导覆盖层的折射率,从而达到衰减波导中光能量的目的.现采用光束传播法(BPM)对设计的新型光衰减器进行了仿真设计,结果表明,设计的光衰减器具有大的动态可调衰减范围(45.3 dB),低的插入损耗(0.8 dB).

ISDTM:An Intrusion Signatures Description Temporal Model

ISDTM, based on an augmented Allen's interval temporal logic (ITL) and first-order predicate calculus, is a formal temporal model for representing intrusion signatures. It is augmented with some real time extensions which enhance the expressivity. Intrusion scenarios usually are the set of events and system states, where- the temporal sequence is their basic relation. Intrusion signatures description, therefore , is to represent such temporal relations in a sense. While representing these signatures, ISDTM decomposes the intrusion process into the sequence of events according to their relevant intervals, and then specifies network states in these Intervals. The uncertain intrusion signatures as well as basic temporal modes of events, which consist of the parallel mode, the sequential mode and the hybrid mode, can be succinctly and naturally represented in ISDTM. Mode chart is the visualization of intrusion signatures in ISDTM, which makes the formulas more readable. The intrusion signatures descriptions in ISDTM have advantages of compact construct, concise syntax, scalability and easy implementation.

SiON钝化膜对硅衬底氮化镓绿光LED可靠性的影响

研制了4种不同表面钝化类型Si衬底GaN基绿光LED,分别标记为样品A、B、C、D。样品A无钝化层,样品B为台面SiON钝化,样品C为侧面SiON钝化,样品D为台面和侧面均钝化。将4种样品进行了常温60 mA(电流密度312 A/cm2)下168 h的加速老化,并对比了老化前后的I-V和光衰等特性。结果表明:侧边的SiON钝化层可有效抑制有源区内非辐射复合缺陷的增加,从而有效降低器件老化后的漏电流和光衰。与台面上的SiON相比,侧边的SiON对钝化起到了决定性作用。

全氢聚硅氮烷衍生法制备耐高温抗氧化SiON涂层

以全氢聚硅氮烷为原料,经加热固化在金属表面制备得到致密均匀、厚度为2μm左右的SiON涂层。研究了全氢聚硅氮烷的固化过程,发现随固化温度升高,水解氧化反应程度提高,随之结构中Si—N、Si—H及N—H强度下降,Si—O强度升高。所得到的涂层硬度达到9H以上,与金属基材之间结合良好,附着力0级。随固化温度升高,涂层表面润湿性能也随之变化,400℃固化得到的涂层表现为亲水性。SiON涂层具备较好的防腐蚀性能和耐高温抗氧化性能,对金属基材具有良好的保护作用,且随着固化温度升高,防腐蚀性能和耐高温性能随之增强。

PECVD SiON膜的性质及其在双层互连工艺中的应用

我们在研制和生产双层布线的 3μm CMOS LSI器件时,采用了 PECVD SiON(等离子增强化学气相沉积的氮氧化硅)膜作金属层之间的绝缘层.这种薄膜具有很小的压应力,很低的针孔密度,良好的台阶覆盖性等优点.这种绝缘膜是采用PECVD沉积工艺,以氮冲稀的低浓度SiH_4(3％)和N_2O气体为原料制得的. 本文着重介绍 PECVD SiON膜的性质及其在双层互连工艺中的应用.

Computation and Measurement of Winding Tension in Ring Spinning

By studying the variations of balloon height and of wind-ing radius in any one winding layer of ring spinning, the formula for determining the winding tension in any layer is derived, and then the overall tension variation throughout all winding layers can be computed. A meth-od of measuring the winding tension is also introduced here, with the measured results agreeing with the com-puted ones, and so the reliable relationship between winding tension, speed and ring traveller weight can be thus obtained. The highest allowable spindle speed is also discussed.

Ibrutinib alleviated LPS-induced neuroinflam⁃mation and synaptic defects in mouse model of depression

OBJECTIVE Previous studies have demonstrated a close association between an altered immune system and major depressive disorders,and inhibition of neuroinflammation may represent an alternative mechanism to treat depression.Recently,the anti-inflammatory activ⁃ity of ibrutinib has been reported.However,the effect of ibrutinib on neuroinflammation-induced depression and its underlying mechanism has not been comprehensively studied.Therefore,we aimed to elucidate the potential anti-depres⁃sive role and mechanism of ibrutinib against neu⁃roinflammation-induced depression and synaptic defects.METHODS AND RESULTS Ibrutinib treatment significantly reduced lipopolysaccha⁃ride(LPS)-induced depressive-like behaviors and neuroinflammation via inhibiting NF-κB acti⁃vation,decreasing proinflammatory cytokine levels,and normalizing redox signaling and its downstream components,including Nrf2,HO-1,and SOD2,as well as glial cell activation mark⁃ers,such as Iba-1 and GFAP.Further,ibrutinib treatment inhibited LPS-activated inflammasome activation by targeting NLRP3/P38/caspase-1 signaling.Interestingly,LPS reduced the number of dendritic spines and expression of BDNF,and synaptic-related markers,including PSD95,snap25,and synaptophysin,were improved by ibrutinib treatment in the hippocampal area of the mouse brain.CONCLUSION Ibrutinib can allevi⁃ate neuroinflammation and synaptic defects,sug⁃gesting it has antidepressant potential against LPS-induced neuroinflammation and depression.

名物化后缀-t/sion在科技英语中的应用研究

以英国国家语料库、交大科技英语语料库分别作为参照语料库和观察语料库,从语料库语言学的角度分析了科技英语中名物化后缀-t/sion的使用情况。通过对比名物化后缀-t/sion与-ment,-ness,-ity在两个语料库中的使用,发现:科技英语文本中名物化词汇使用较多,其中以-t/sion转换而来的名物化词汇在科技英语词汇中的使用最具典型性;语义层面,该名物化后缀主要用于描述科技领域中的各种现象、操作步骤和事物性质。

Diffusion Based Molecular Communication:Principle,Key Technologies,and Challenges

Molecular communication(MC) is a kind of communication technology based on biochemical molecules for internet of bio-nano things, in which the biochemical molecule is used as the information carrier for the interconnection of nano-devices. In this paper, the basic principle of diffusion based MC and the corresponding key technologies are comprehensively surveyed. In particular, the state-ofthe-art achievements relative to the diffusion based MC are discussed and compared, including the system model, the system performance analysis with key influencing factors, the information coding and modulation techniques. Meanwhile, the multi-hop nano-network based on the diffusion MC is presented as well. Additionally, given the extensiveness of the research area, open issues and challenges are presented to spur future investigations, in which the involvement of channel model, information theory, self-organizing nano-network, and biochemical applications are put forward.

Discriminative Latent Model Based Chinese Multiword Expression Extraction

Discriminative Latent Model(DLM) is proposed for Multiword Expressions(MWEs) extraction in Chinese text to improve the performance of Machine Translation(MT) system such as Template Based MT(TBMT).For MT systems to become of further practical use,they need to be enhanced with MWEs processing capability.As our study towards this goal,we propose DLM,which is developed for sequence labeling task including hidden structures,to extract MWEs for MT systems.DLM combines the advantages of existing discriminative models,which can learn hidden structures in sequence labeling task.In our evaluations,DLM achieves precisions ranging up to 90.73% for some type of MWEs,which is higher than state-of-the-art discriminative models.Such results demonstrate that it is feasible to automatically identify many Chinese MWEs using our DLM tool.With MWEs processing model,BLEU score of MT system has also been increased by up to 0.3 in close test.

Theoretical and numerical investigation of HF elastic wave propagation in two-dimensional periodic beam lattices

The elastic wave propagation phenomena in two-dimensional periodic beam lattices are studied by using the Bloch wave transform. The numerical modeling is applied to the hexagonal and the rectangular beam lattices, in which, both the in-plane （with respect to the lattice plane） and out-of-plane waves are considered. The dispersion relations are obtained by calculating the Bloch eigenfrequencies and eigenmodes. The frequency bandgaps are observed and the influence of the elastic and geometric properties of the primitive cell on the bandgaps is studied. By analyzing the phase and the group velocities of the Bloch wave modes, the anisotropic behaviors and the dispersive characteristics of the hexagonal beam lattice with respect to the wave prop- agation are highlighted in high frequency domains. One im- portant result presented herein is the comparison between the first Bloch wave modes to the membrane and bend- ing/transverse shear wave modes of the classical equivalent homogenized orthotropic plate model of the hexagonal beam lattice. It is shown that, in low frequency ranges, the homog- enized plate model can correctly represent both the in-plane and out-of-plane dynamic behaviors of the beam lattice, its frequency validity domain can be precisely evaluated thanks to the Bloch modal analysis. As another important and original result, we have highlighted the existence of the retro- propagating Bloch wave modes with a negative group veloc- ity, and of the corresponding ＂retro-propagating＂ frequency bands.

A Wireless Intrusion Alerts Clustering Method for Mobile Internet

With the rapid development of mobile Internet, people pay increasing attention to the wireless network security problem. But due to the specificity of the wireless network, at present it is rare to see the research of wireless intrusion alerts clustering method for mobile Internet. This paper proposes a Wireless Intrusion Alert Clustering Method(WIACM) based on the information of the mobile terminal. The method includes alert formatting, alert reduction and alert classification. By introducing key information of the mobile terminal device, this method aggregates the original alerts into hyper alerts. The experimental results show that WIACM would be appropriate for real attack scenarios of mobile Internet, and reduce the amount of alerts with more accuracy of alert analysis.

Danhong injection A modulator for Golgi structural stability after cerebral ischemiareperfusion injury

The cerebral ischemia-reperfusion model was established using the suture occlusion method, and rats were intraperitoneally given 8 mL/kg Danhong injection once a day prior to model establishment Rat brain tissues were harvested at 6, 24, 48, 72 hours after reperfusion. Immunohistochemical staining showed that transforming growth factor-J31 expression increased, while Golgi matrix protein GM130 expression decreased after cerebral ischemia-reperfusion. Danhong injection was shown to significantly up-regulate the expression of transforming growth factor-131 and GM130, and expres- sion levels peaked at 7 days after reperfusion. At 7 days after cerebral ischemia-reperfusion, Golgi morphology was damaged in untreated rats, while Golgi morphology breakage was not observed after intervention with Danhong injection. These experimental findings indicate that Danhong injec- tion can up-regulate the expression of transforming growth factor-131 and GM130, and maintain Golgi stability, thus playing a neuroprotective role in rats after cerebral ischemia-reperfusion.

Application of wavelet support vector regression on SAR data de-noising

A new filtering method for SAR data de-noising using wavelet support vector regression （WSVR） is developed. On the basis of the grey scale distribution character of SAR imagery, the logarithmic SAR image as a noise polluted signal is taken and the noise model assumption in logarithmic domain with Gaussian noise and impact noise is proposed. Based on the better per- formance of support vector regression （SVR） for complex signal approximation and the wavelet for signal detail expression, the wavelet kernel function is chosen as support vector kernel func- tion. Then the logarithmic SAR image is regressed with WSVR. Furthermore the regression distance is used as a judgment index of the noise type. According to the judgment of noise type every pixel can be adaptively de-noised with different filters. Through an approximation experiment for a one-dimensional complex signal, the feasibility of SAR data regression based on WSVR is con- firmed. Afterward the SAR image is treated as a two-dimensional continuous signal and filtered by an SVR with wavelet kernel function. The results show that the method proposed here reduces the radar speckle noise effectively while maintaining edge features and details well.

High Temperature Corrosion and Protection of Titanium Alloys and TiAl Intermetallics

High temperature corrsoion and protection of trtanium alloys and TiAl intermetallics are reviewed, andsome suggestions on the development of protective coatings are put forward.

A Particle Induced X-Ray Emission (PIXE) Analysis of Heavy Metals in Soil and Plantain (<i>Musa paradisiaca</i>) Leaves at an Artisanal Gold Mining Settlement in Southwestern Nigeria

The study examined the contamination levels of the soil and plantain leaves in three communities in Atakunmosa west local government area of Osun State in southwest Nigeria, where gold mining activities have recently become intensive. Plantain is a major food crop, whose leaves are used to wrap food items for household consumption. The objectives were to examine the heavy metal concentrations in the soil and plantain leaves around the gold mine site and compare them with standard recommended safe limits for the environment. Soil and plantain leaves were sampled at different locations around the sites and at a control site from a neighboring local government area with no history of gold mining activities between March 2015 and February 2016. Both soil and leave samples were processed and analyzed for selected heavy metals (Cd, As, Cu, Zn, Cr, Mn and Fe) using the Particle Induced X-ray Emission (PIXE) in the laboratory. The study showed higher concentrations than the World Health Organization’s recommended safe limits of the heavy metals in the soils and plantain leaves. Dry season concentrations of the variables were also higher than the wet season and the heavy metal concentrations at the control station were significantly (p < 0.05) lower than those of the mining environment. The study concluded that the ecosystems in the artisanal gold mining region are vulnerable to bioaccumulation of heavy metals and the leaves from the sites are sources of heavy metal contamination if consumed or used to wrap food items.

Torsional Models of Two-ply Yarn

In this paper,the vector equation of a generaliseddoubly wound helix was derived.Treloar’s pliedyarn geometry could be obtained as a special case ofthe generalised doubly wound helix.The shortest fi-bre length around the surface of a helical tube(formed by fibre helices)was determined by apply-ing variational principles.The fibre length as calcu-lated by using Treloar’s geometry was compared in-directly with the shortest possible fibre length at dif-ferent levels of yarn deformation when some of Tre-loar’s rigid geometrical constraints were relaxed.Anew idea based on non-concentric circles was intro-duced to approximate the fibre helix movement in atwo-ply yarn.A torsional model of two-ply yarnwas developed and the theoretical predictions werecompared with some preliminary experimental re-sults.