A Hetero-Layered,Mechanically Reinforced,Ultra-Lightweight Composite Polymer Electrolyte for Wide-Temperature-Range,Solid-State Sodium Batteries

The practical use of polyethylene oxide polymer electrolyte in the solid-state sodium metallic batteries (SSMBs) suffers from the retard Na⁺ diffusion at the room temperature, mechanical fragility as well as the oxidation tendency at high voltages. Herein, a hetero-layered composite polymeric electrolyte (CPE) is proposed to enable the simultaneous interfacial stability with the high voltage cathodes (till 4.2 V) and Na metallic anode. Being incorporated within the polymer matrix, the sand-milled Na₃Zr₂Si₂PO₁₂ nanofillers and nanocellulose scaffold collectively endow the thin-layer (25 µm), ultralightweight (1.65 mg cm⁻²) CPE formation with an order of magnitude enhancement of the mechanical strength (13.84 MPa) and ionic conductivity (1.62 × 10⁻⁴ S cm⁻¹) as compared to the pristine polymer electrolyte, more importantly, the improved dimension stability up to 180 °C. Upon the integration of the hetero-layered CPE with the iron hexacyanoferrate FeHCF cathode (1 mAh cm⁻²) and the Na foil, the cell model can achieve the room-temperature cycling stability (93.73% capacity retention for 200 cycles) as well as the high temperature tolerance till 80 °C, which inspires a quantum leap toward the surface-wetting-agent-free, energy-dense, wide-temperature-range SSMB prototyping.     

Lithiation-Induced Defect Engineering to Promote Oxygen Evolution Reaction

Exploring efficient electrocatalysts for oxygen evolution reaction (OER) is an urgent need to advance the development of sustainable energy conversion. Though defect engineering is considered an effective strategy to regulate catalyst activity for enhanced OER performance, the controllable synthesis of defective oxides electrocatalysts remains challenging. Here, oxygen defects are introduced into NiCo₂O₄ nanorods by an electrochemical lithiation strategy. By tuning in situ lithiation potentials, the concentration of oxygen defects and the corresponding catalytic activity can be feasibly regulated. In addition, the relationship between the changes in the defect density and electronic structure and the lithiation cut-off voltages is revealed. The results show that NiCo₂O₄ nanorods undertook intercalation and two-step conversion reaction, in which the lithiation-induced conversion reaction gives rise to a CoO@NiO-based structure with higher defect density and lower oxidation states. As a result, the defective CoO@NiO-based catalyst exhibits exceptional OER activity with an overpotential of 270 mV at 10 mA cm⁻², which is about 74 mV below the pristine nanomaterials. This research proposes a novel strategy to explore high-performance catalysts with structural stability and defect control.     

微机电系统扭转微镜面驱动器的研制

提出了一种新颖的采用键合减薄工艺制作的微机电系统扭转微镜面驱动器,该种微镜面驱动器工艺制作简便可行.通过对研制的微镜面驱动器进行测试,该驱动器在18V驱动电压时可以达到0.3°的扭转角度,微镜面的频率响应时间小于1ms.同时该驱动器具有较大的微反射镜面,面积达到600μm×700μm,试验结果表明微镜面驱动器将可以应用于光通信领域.     

An Efficient Multi-Path Self-Organizing Strategy in Internet of Things

In order to improve the organizing performance and fault tolerance of the wireless network protocol GEAR based on the geographical location information in the Internet of things and achieve better energy distribution and conservation effects. This paper proposes a new multipath routing organizing protocol (SMG, Self-organized Multipath GEAR) based on the basic geographic routing protocol GEAR. By two-step organizing, communication empty nodes and communication hole can join the network respectively and energy spreading out and mechanism of dormancy of the multi-path are utilized to spread out and save energy. Meanwhile, this paper presents an approximate estimation algorithm to estimate the number of the nodes in the monitoring region with a certain size and regular shape. The critical path node goes to failure in different times while received packet rate is monitored using the experiment of NS2 simulation and actual hardware. The experiment results show that the improved protocol increases the fault tolerance of the network, reduces the paralysis rate of the network and achieves the effect of energy spreading out and saving, increases the lifetime of the network through a multi-path strategy.     

微型光机电系统及其制作

微型光机电系统 (MOEMS)是将微光学、微电子和微机械系统结合发展出一种新型、宽广的应用领域 ,从早期的分立光学元件与电子电路向独立完整的光学系统发展。阐述了实现MOEMS的 2种技术手段 :光波导和微型光学平台的原理、制作工艺和关键技术 ,在此基础上概要介绍了几种典型的MOEMS系统。最后对其的发展作了展望。     

3300V 4H-SiC MOSFET 设计与加工

成功设计并制造了击穿电压超过3300V 的4H-SiC MOSFET。通过数字仿真优化了漂移层和DMOSFET有源区参数。漂移层N型外延厚度为33微米并且掺杂浓度为2.5E15cm-3。器件采用浮空场限制环作为终端。当栅极电压为20V,漏极电压为2.5V时,漏极电流为5A。     

安徽省电信宽带城域网的几种业务

本介绍了安徽电信宽带IP城域网可以开展的几种主要接入业务，并对几种业务的实现方式进行说明。     

Property of Self-Similarity Between Baseband and Modulated Signals

Mobile Networks and Applications - The increment of communication technologies and the development of signal processing require efficient identification techniques for communication...     

Perfect sampling: a review and applications to signal processing

Markov chain Monte Carlo (MCMC) sampling methods have gained much popularity among researchers in signal processing. The Gibbs and the Metropolis-Hastings (1954, 1970) algorithms, which are the two most popular MCMC methods, have already been employed in resolving a wide variety of signal processing problems. A drawback of these algorithms is that in general, they cannot guarantee that the samples are drawn exactly from a target distribution. New Markov chain-based methods have been proposed, and they produce samples that are guaranteed to come from the desired distribution. They are referred to as perfect samplers. We review some of them, with the emphasis being given to the algorithm coupling from the past (CFTP). We also provide two signal processing examples where we apply perfect sampling. In the first, we use perfect sampling for restoration of binary images and, in the second, for multiuser detection of CDMA signals     

A GaN/InGaN/AlGaN MQW RTD for versatile MVL applications with improved logic stability

To improve the logic stability of conventional multi-valued logic (MVL) circuits designed with a GaN-based resonate tunneling diode (RTD),we proposed a GaN/InGaN/AlGaN multi-quantum well (MQW) RTD.The proposed RTD was simulated through solving the coupled Schrodinger and Poisson equations in the numerical non-equilibrium Green's function (NEGF) method on the TCAD platform.The proposed RTD was grown layer by layer in epitaxial technologies.Simulated results indicate that its current-voltage characteristic appears to have a wider total negative differential resistance region than those of conventional ones and an obvious hysteresis loop at room temperature.To increase the Al composite of AlGaN barrier layers properly results in increasing of both the total negative differential resistance region width and the hysteresis loop width,which is helpful to improve the logic stability of MVL circuits.Moreover,the complement resonate tunneling transistor pair consisted of the proposed RTDs or the proposed RTD and enhanced mode HEMT controlled RTD is capable of generating versatile MVL modes at different supply voltages less than 3.3 V,which is very attractive for implementing more complex MVL function digital integrated circuits and systems with less devices,super high speed linear or nonlinear ADC and voltage sensors with a built-in super high speed ADC function.