20A

220V / 20A High Frequency Switched Power Supply Research Base on PWM Technology

基于PWM技术的220V/20A高频开关电源的开发

Corrosion of 20a steel in solution with low phosphate and low NaOH

低磷酸盐-低NaOH模拟炉水中20A碳钢的腐蚀

Corrosion of 20A Carbon Steel in Boiler Water Containing Cl-at High Temperature

模拟高温炉水中Cl~-对20A碳钢的腐蚀研究

48V / 20A High Frequency Switching Mode Power Supply

48V/20A高频开关电源

They put in a $ 20a week pay claim .

他们提出每周工资20英镑的要求。

Anaerobes isolated form anaerobic culture were identified using APl 20A System .

应用API20A鉴定系统对分离到的厌氧菌菌种进行鉴定。

You can only claim $ 20a day for your travel .

你每天只能报销20美元旅差费。

We allowed for living expenses of $ 20a day .

我们计划每天的生活费是20英镑。

Test 20A continued from the previous page .

接上页，继续测试20A。

She receive & 20a week as unemployment benefit .

她每周领取20英镑的失业救济金。

A pay rise of $ 20a week .

每周20英镑的工资增加。

The stock traded around $ 20a share .

这份股票以大约$20一份交易。

The meal worked out at $ 20a head .

这餐饭合计每人20元。

20A young girl is seen feeding the swans in a sheltered public park .

一个年轻姑娘正在一个受保护的公共公园里喂天鹅。

Change trend of water environment index in recent 20a in Qinzhou Bay ⅲ Content distribution of trace metal and its source analysis

钦州湾近20a来水环境指标的变化趋势Ⅲ微量重金属的含量分布及其来源分析

Research on Charger for Storage Battery ( 48V / 20A · h ) of Electric-vehicle

电动车用48V（20A·h）蓄电池充电器的研究

The main factors influencing octadecylamine ( ODA ) film formed on 20A carbon steel were studied by autoclave test and polarization curves .

通过高压釜试验，对影响十八胺（ODA）在20A碳钢试片表面成膜的主要因素进行了研究，并进行了电化学测试。

The corrosion inhibition effect of molybdate inhibitor in tap water on 20A carbon steel has been studied with electrochemical polarization curve and impedance test .

为此，通过电化学极化曲线与交流阻抗实验，研究了钼酸盐系列缓蚀剂在自来水中对20A碳钢的缓蚀情况。

Therefore , this study is based on MSS and TM image during five periods in 1978,1988,1992,1996 and 2001 , obtaining land utilization information in different periods of 20a .

为此，本研究基于大庆市1978、1988、1992、1996和2001年5个时段的MSS和TM影像.获取20a来不同时期的土地利用信息。

Based on the dating results , five Quaternary glaciation stages are determined primarily as follows : Little Ice Age , Stage ⅲ( 1871 ± 20A . D. )

90年代以后，采用热释光和电子自旋共振技术测年，获得了我国第四纪冰川的一些数值年代，划分了5次冰期，其时代初步定为：小冰期Ⅲ（1871±20A.D.）

Based on the current sources designed , 20A peak current composite-structure current mode EDM power and 20A ^ 50A peak current two-stage current mode EDM power are built .

在此基础之上，设计了20A峰值电流复合结构电流型EDM电源样机和20A、50A峰值电流两级结构电流型EDM电源样机。

A significantly negative correlation was established between crop-load and cracked fruit percentage . The wild tree fruit in 10a , and arrived maximum in 20a .

树体的挂果量与裂果率呈极显著的负相关。野生状态南酸枣10a挂果，20a进入盛果期。

When the Nd : YAG module driven current is 20A , 15W CW green laser output power is obtained , with optical-optical conversion efficiency of 9.7 % .

在模块驱动电流为21.4A时，获得功率高达15W的连续绿光输出，光-光转换效率达到9.7%。

The circulating levels of miR-17-5p / 20a in all groups were tested by quantitative RT-PCR . Their clinical significance was analyzed combined with the clinical pathological materials of the pre-operative groups .

采用定量RT-PCR比较循环miR-17-5p/20a表达量，结合术前患者病理资料分析其临床意义以及与病程相关性。

Finally , the operation principle of Zero-voltage and Zero-current-switching PWM three-level converter is validated by the simulation analyze and the debugging experiment of 50V / 20A sample device .

最后，通过仿真分析和对50V/20A样机的调试实验，验证了零电压零电流移相控制PWM三电平直流变换器的工作原理。

The quasi - intelligent measuring circuit of direct current is accomplished in this paper . This is measure circuit with scale less and internal resistance constantly is 0.01 Ω in 0 - 20A measuring range .

文中实现了直流电流的准智能测量，即无档测量，且在0～20A测量范围内做到内阻恒为0.01Ω。

This paper introduced that Scr - 20A screw compressors replaced traditional cork compressors in the pushing coke lathe of coke - oven successfully and satisfactory results are obtained from practical production .

阐述SCR-20A型螺杆式空压机成功取代传统活塞式空压机在焦炉推焦车上的使用及效果。

Also , four kinds of corrosion inhibitor are appraised . The results show that , Fe ~ ( 3 + ) ion can accelerate the corrosion of 20A steel in the cleaning solution enormously ;

结果表明，Fe~（3+）具有加速清洗液腐蚀碳钢的作用，使20A碳钢的腐蚀速率成倍增大；

Present Situation , Problems and Countermeasures on Cleaning Lampblack of Urban Catering Services The evolution of eco-environment in the past 20a in the area near Ebinur Lake and analysis of the value of ecosystem services

浅析饮食业油烟污染防治现状、问题及对策艾比湖沿岸地区环境质量演变与生态价值分析

The plasma in the axis is in LTE state while the arc operating inargon ( pressure 0.1 MPa to 0.5MP_a , the arc current ≥ 20A ) .

当压力为0.1～0.5MPa、电流不小于20A时，电弧轴心区等离子体是LTE（局部热力学平衡）的。