Effects of rare earth elements on properties of AB5-type electrode materials at different temperature

Discharge property is an important factor to evaluate electrode materials. The discharge capacity of the hydrogen-storing alloys are not only influenced by its thermodynamic property but also closely related to its dynamic property. When the temperature changes, the degrees of influence of the above-mentioned two factors on the discharge performance vary accordingly. As a consequence, adjusting compositions of the alloys to make them have good discharge performance under a relatively wide range of temperature is of great significance. On the basis of great deal of experimental investigation, the optimum combination of rare earth elements in hydrogen-storing electrode materials using at-30-55℃ is determined and the relationships between the cell parameters and discharge performance of alloys at -30℃ are discussed. Additionally, the DFEC calculation method has been improved to predict the discharge capacities, which is in good agreement with the experimental ones. This is of theoretical significance in investigating new hydrogen-storing alloys of the AB5 type.     

基于AB PLC5系统的缸体加工自动线改造

分析了AB PLC5替代AB PLC2在深孔加工自动线改造中的应用,讨论了系统的结构配置、硬件组成和软件升级。该系统运行可靠。     

一种微功耗轨到轨输出AB类运算放大器设计

在分析研究AB类运算放大器的输入和输出级构成原理基础上,提出一种与信号处理模块的输出端匹配并具有一定负载能力的缓冲器的设计。缓冲器采用了AB类运放结构,其输入级采用折叠式共射共基结构,输出级分别采用PNP管和NMOS管作为上拉管和下拉管,结合电路结构的改进使之具有轨到轨(rail-to-rail)的输出特性和很低的静态电流。设计的电路具有开环增益大、静态功耗小、带宽较高等特点。此运放已在1.5μmBCD工艺下实现。测试结果表明,静态电流仅为8.5μA,闭环带宽达200kHz,开环增益为100dB。     

Power‐efficient analog design based on the class AB super source follower

A class AB version of the conventional super source follower (SSF) is described. The circuit greatly increases slew rate (SR) and current efficiency, maintaining the low distortion and low output resistance of the SSF. Class AB operation is achieved without extra power dissipation or supply requirements, and without bandwidth or noise degradation. The circuit can advantageously replace the SSF in a wide variety of analog systems, opening a new research line in analog design. To illustrate the widespread application of this cell, a class AB differential unity‐gain buffer, a class AB differential current mirror and two class AB differential transconductors are designed, fabricated in a 0.5µm CMOS technology and tested. Measurement results using a dual supply of ±1.65V show that the proposed class AB version of the SSF improves SR by a factor 21.5 and increases bandwidth by 10%, keeping noise level, input range, power consumption, and supply requirements unaltered. The fabricated class AB current mirror features a THD at 100 kHz of ? 62dB for signal currents 20 times larger than the bias current. The fabricated transconductors feature an IM3 at 1 MHz of ? 56.6dB for output currents more than 13 times larger than the bias currents. Copyright © 2011 John Wiley & Sons, Ltd.     

染料酸性蓝水溶液光催化氧化脱色研究

以300W高压汞灯为光源,TiO2为催化剂,对光催化剂用量,H2O2的投加,溶液的起始浓度等因素对高浓度酸性蓝(AcidBlue)(1g/L)水溶液的光催化氧化脱色的影响进行研究。结果表明:TiO2的投加量在0~2mg/L范围内,对染料的脱色率影响较小。仅加入TiO2,光照50h,脱色率达11.2%;仅加入H2O2,光照50h,脱色率达31.2%;同时加入TiO2和H2O2,光照50h,脱色率达70.1%。随着酸性蓝起始浓度的降低,脱色率随之增加。     

一种具有采样带宽补偿的高性能采样/保持电路

针对中频采样模数装换器中的宽带采样/保持电路,提出了一种新颖的电荷交换补偿（CEC）技术.该技术通过消除采样开关有限导通电阻的影响,补偿了采样带宽,并避免了时钟馈通和电荷注入的加剧.同时设计了具有AB类输出的低功耗两级运放,在1.8V电源下为该采样/保持提供了3V峰-峰值的输入范围.该采样/保持电路在100Ms/s的采样率下,对于200MHz输入信号达到了94dB的无杂散动态范围.在5.5pF的负载下,功耗仅为26mW.     

具有温控保护的低谐波失真AB类音频功放

设计了一款应用于电视机、PC音响等系统的AB类四通道音频功率放大器.实现最低谐波失真为0.148%.同时提出了一种新型BE结负温反馈温度监控保护电路.在电路中设置温度传感器,当芯片温度高于150℃或局部温度高于180℃时,关断功率输出级2.8ms.使用先进3μm高压双极型工艺进行版图设计并成功流片.对芯片实测显示,此功放可提供1～50W的功率输出,输出效率达到35%,总谐波失真小于1%.     

Modeling California policy impacts on greenhouse gas emissions

This paper examines policy and technology scenarios in California, emphasizing greenhouse gas (GHG) emissions in 2020 and 2030. Using CALGAPS, a new, validated model simulating GHG and criteria pollutant emissions in California from 2010 to 2050, four scenarios were developed: Committed Policies (S1), Uncommitted Policies (S2), Potential Policy and Technology Futures (S3), and Counterfactual (S0), which omits all GHG policies. Forty-nine individual policies were represented. For S1–S3, GHG emissions fall below the AB 32 policy 2020 target [427 million metric tons CO₂ equivalent (MtCO₂e) yr⁻¹], indicating that committed policies may be sufficient to meet mandated reductions. In 2030, emissions span 211–428 MtCO₂e yr⁻¹, suggesting that policy choices made today can strongly affect outcomes over the next two decades. Long-term (2050) emissions were all well above the target set by Executive Order S-3-05 (85 MtCO₂e yr⁻¹); additional policies or technology development (beyond the study scope) are likely needed to achieve this objective. Cumulative emissions suggest a different outcome, however: due to early emissions reductions, S3 achieves lower cumulative emissions in 2050 than a pathway that linearly reduces emissions between 2020 and 2050 policy targets. Sensitivity analysis provided quantification of individual policy GHG emissions reduction benefits.     

High-gain,high-CMRR class AB operational transconductance amplifier based on the flipped voltage follower

A novel class AB operational transconductance amplifier (OTA) topology is proposed, based on a class AB flipped voltage follower. The OTA has class AB behavior, with current boosting both for the load and the compensation capacitors. It has a high gain of (g_mr₀)⁴ , obtained using a two-stage structure with cascoded stages, and is a two-stage Miller-compensated amplifier employing multipath to remove the positive zero. It has close to rail-to-rail output swing (limited by cascoding) and very low common-mode gain thanks to a replica technique (allowing the use of low-power common-mode feedback [CMFB] loops). Ninety-two decibels of gain and 176 dB of common-mode rejection ratio (CMRR) without CMFB are achieved using a 40-nm complementary metal-oxide semiconductor (CMOS) process. The OTA is used to design a low-power sample-and-hold amplifier (SHA) operating at 5 MSps, a typical application for CMOS OTAs, which has been chosen to verify the proposed circuit's performance and to show that the OTA is robust in Monte Carlo simulations under process variations and mismatches in an actual application.     

基于MC68HC908AB32的滚筒洗衣机控制器

介绍了基于MC68HC908AB32单片机的滚筒洗衣机控制器。文章概述了控制器的工作原理，并给出双速电机的调速电路和洗衣机控制软件的设计方案。