U1B

高中英语单词转换强化训练U1B7（为语法填空题作铺垫）贵阳市乌当中学高力超选修7Unit 11. disability（反义词、形容词）ability, disabled2. disabled（反义词、名词）able, disability3. hearing (动词) hear4. eyesight（同义词）seeing5. dictation (动词) dictate6. noisy (名词、副词) noise，noisily7. suitable (同义词、动词、反义词) fit, suit, unsuitable8. entry (动词、名词) enter, entrance9. beneficial ((名词、动词、反义词) benefit, benefit, harmful10. clumsy (同义词、反义词) unskillful, unhandy, clever, smart, wise, intelligent11. outgoing (同义词) friendly, kind, outward, out12. adapt（形容词）adapted13. bench (复数) benches14. cut out (同义词组) cut off, stop doing sth.15. microscope（相对词）telescope16. absence (形容词、反义词) absent, presence17. fellow (同义词) companion, , partner, mate18. annoy (两个形容词) annoying, annoyed19. annoyed (另一个形容词，原形) annoying, annoy20. firm（同义词、副词）company, corporation, solid, hard, stable, firm,firmly21. all in all (同义词组) generally speaking, in short, in a word22. software (反义词) hardware23. as well as（同义词）and, with24. encouragement (动词) encourage25. conduct (名词、同义词) conductor, action, behavior, command, direct, manage, control, govern, host26. never mind (同义词) don’t need to worry27. politics（形容词、指人的名词）political, politician28. abolish (同义词组) do away with, put an end to29. resign (同义词组) quit office30. slavery (指人的名词) slave31. literature (同义词) letter, works32. companion (同义词) mate, fellow, partner33. assistance (动词、同义词) assist, help, aid, support34. congratulate (名词、同义词) congratulation, celebration35. graduation (动词、指人的名词、形容词) graduate, graduate,graduate36. architect(另一个名词) architecture37. adequate (同义词、反义词) enough, adequate, plenty, abundant, wealthy, ample, lacking38. access (形容词、同义词) accessible, method, way, process, means, passage39. accessible (名词) access40. handy (同义词、反义词) useful, helpful, available, convenient, useless41. row (同义词、同义词组) line, go boating42. exit (同义词、反义词) way out, departure, entrance, entry43. meet with (同义词组、同义词) come across, run into, go through, experience44. approval (动词、同义词) approve, favor, confirm, accept45. dignity (同义词) honor46. profit (同义词) income47. community (同义词) group, team, organization, society, world答案：1. ability, disabled2. able, disability3. hear4. seeing5. dictate6. noise，noisily7. fit, suit, unsuitable8. enter, entrance9. benefit, benefit, harmful10. unskillful, unhandy, clever, smart, wise, intelligent11. friendly, kind, outward, out12. adapted13. benches14. cut off, stop doing sth.15. telescope16. absent, presence17. companion, , partner, mate18. annoying, annoyed19. annoying, annoy20. company, corporation, solid, hard, stable, firm,firmly21. generally speaking, in short, in a word22. hardware23. and, with24. encourage25. conductor, action, behavior, command, direct, manage, control, govern, host26. don’t need to worry27. political, politician28. do away with, put an end to29. quit office30. slave31. letter, works32. mate, fellow, partner33. assist, help, aid, support34. congratulation, celebration35. graduate, graduate,graduate36. architecture37. enough, adequate, plenty, abundant, wealthy, ample, lacking38. accessible, method, way, process, means, passage39. access40. useful, helpful, available, convenient, useless41. line, go boating42. way out, departure, entrance, entry43. come across, run into, go through, experience44. approve, favor, confirm, accept45. honor46. income47. group, team, organization, society, world。

New ProductU1B, U1C & U1DVishay General SemiconductorDocument Number: 89065For technical questions within your region, please contact one of the following:Surface Mount Ultrafast Plastic RectifierFEATURES•Oxide planar chip junction•Ultrafast recovery time•Low forward voltage, low power losses•High forward surge capability•Meets MSL level 1, per J-STD-020, LF maximumpeak of 260 °C•Solder dip 260 °C, 40 s•Component in accordance to RoHS 2002/95/ECand WEEE 2002/96/ECTYPICAL APPLICATIONSFor use in low voltage, high frequency rectifierof switching power supplies, freewheeling diodes,dc-to-dc converters or polarity protection application.MECHANICAL DATACase: DO-214AC (SMA)Epoxy meets UL 94V-0 flammability ratingTerminals: Matte tin plated leads, solderable perJ-STD-002 and JESD22-B102E3 suffix for consumer grade, meets JESD 201 class1A whisker testPolarity:Color band denotes cathode endPRIMARY CHARACTERISTICSI F(AV)1.0 AV RRM100 V, 150 V, 200 VI FSM30 At rr15 nsV F at I F = 1.0 A0.76 VT J max.150 °CDO-214AC (SMA)MAXIMUM RATINGS (T A = 25°C unless otherwise noted)PARAMETER SYMBOLU1BU1CU1DUNIT Device marking code U1B U1C U1DMaximum repetitive peak reverse voltage V RRM 100150200VMaximum average forward rectified current (Fig. 1)I F(AV) 1.0 APeak forward surge current 8.3 ms single half sine-wavesuperimposed on rated loadI FSM 30 AOperating junction and storage temperature range T J, T STG- 55 to + 150 °C元器件交易网New ProductU1B, U1C & U1DVishay General Semiconductor For technical questions within your region, please contact one of the following:Document Number: 89065Notes:(1) Pulse test: 300 µs pulse width, 1 % duty cycle (2) Pulse test: Pulse width ≤ 40 msNote:(1) Free air, mounted on recommended copper pad areaRATINGS AND CHARACTERISTICS CURVES (T A = 25 °C unless otherwise noted)ELECTRICAL CHARACTERISTICS (T A = 25°C unless otherwise noted)PARAMETER TEST CONDITIONS SYMBOL TYP.MAX.UNITInstantaneous forward voltage (1)I F = 0.6 AI F = 1.0 A T A = 25 °CV F0.820.870.870.92VI F = 0.6 A I F = 1.0 A T A = 100 °C 0.710.760.780.84Reverse current (2)rated V RT A = 25 °C T A = 100 °C I R -55 5.0100µA Reverse recovery timeI F = 0.5 A, I R = 1.0 A,I rr = 0.25 AT A = 25 °C t rr-15ns I F = 0.6 A, dI/dt = 50 A/µs, V R = 30 V, I rr = 0.1 I RM T A = 25 °C T A = 100 °C t rr 2429--ns Storage chargeI F = 0.6 A, dI/dt = 50 A/µs, V R = 30 V, I rr = 0.1 I RM T A = 25 °C T A = 100 °CQ rr713--nCTypical junction capacitance4.0 V , 1 MHzC J 6.8-pFTHERMAL CHARACTERISTICS(T A = 25°C unless otherwise noted)PARAMETERSYMBOL U 1B U1C U 1DU NIT Typical thermal resistance (1)R θJA R θJM11522°C/WORDERING INFORMATION (Example)PREFERRED P/N UNIT WEIGHT (g)PREFERRED PACKAGE CODEBASE QUANTITYDELIVERY MODEU1D-E3/61T 0.06461T 18007" diameter plastic tape and reel U1D-E3/5AT0.0645AT750013" diameter plastic tape and reelFigure 1. Forward Derating CurveFigure 2. Forward Power Loss Characteristics元器件交易网New ProductU1B, U1C & U1DVishay General SemiconductorDocument Number: 89065For technical questions within your region, please contact one of the following: PACKAGE OUTLINE DIMENSIONS in inches (millimeters)Figure3. Typical Instantaneous Forward CharacteristicsFigure4. Typical Reverse CharacteristicsFigure5. Typical Junction CapacitanceFigure6. Typical Transient Thermal Impedance元器件交易网Disclaimer Legal Disclaimer NoticeVishayAll product specifications and data are subject to change without notice.Vishay Intertechnology, Inc., its affiliates, agents, and employees, and all persons acting on its or their behalf (collectively, “Vishay”), disclaim any and all liability for any errors, inaccuracies or incompleteness contained herein or in any other disclosure relating to any product.Vishay disclaims any and all liability arising out of the use or application of any product described herein or of any information provided herein to the maximum extent permitted by law. The product specifications do not expand or otherwise modify Vishay’s terms and conditions of purchase, including but not limited to the warranty expressed therein, which apply to these products.No license, express or implied, by estoppel or otherwise, to any intellectual property rights is granted by this document or by any conduct of Vishay.The products shown herein are not designed for use in medical, life-saving, or life-sustaining applications unless otherwise expressly indicated. Customers using or selling Vishay products not expressly indicated for use in such applications do so entirely at their own risk and agree to fully indemnify Vishay for any damages arising or resulting from such use or sale. Please contact authorized Vishay personnel to obtain written terms and conditions regarding products designed for such applications.Product names and markings noted herein may be trademarks of their respective owners.元器件交易网Document Number: 。

新版小学六年级上册英语Unit 1 How can I get there? 教案第四课时 B Let’s try &Let’s talk一、教学目标与要求1．能够听、说、认读句子,并能在情景中进行运用。

2．能够掌握重点句子：How can we get there? 并能回答Turn left at the bookstore. Then turn right at the hospital.二、教学重、难点本课时的教学重点和难点是使学生掌握句型：“How can we get to the …?Turn left\right at ...三、教学准备：多媒体课件。

单词图片四、教学步骤和建议Step1．Preparation1、听指令做动作。

请学生根据教师的指令做动作并且大声地读出该单词。

2．Let's try教师放Let's try时部分的录音，学生做出正确的选择。

Wu Yifan is cal ling Mike. Listen and tick or cross.1. ( ) They want to go to the bookstore.2. ( ) The cinema is next to the bookstore.Step 2.Presentation1、教学what an interesting film !出示上节课所学的句子 what a great museum ! 由great 引出interesti ng让学生根据规律替换并试读，教师领读。

接着老师走到一名学生旁边说：wha t an interesting film !2、教学How can we get there?出示第五页的地图，由上面可以导出我们想去电影院，但怎么去如何说，老师走到学生跟前问：How can we get there? 让学生试着理解，教师领读，学生跟读，并采用各种方式进行读。

使用NMOS场效应管的白光烙铁控制电路原理简介：U1B组成一个单稳态电路，时间由R4和C3决定。

上电时，6脚为低电平，7脚输出高电平，通过9013使MOS管导通，烙铁芯通电升温。

MOS导通时，电源电压通过R1加在LM358的3脚上，由于D1的限压，3脚得到约0.7V的电压，远大于2脚上毫伏级电压，使1脚输出高电平。

零点几秒后，C3充满，7脚输出低电平，MOS断开，这时热电偶产生的电压通过R1加在LM358的3脚上，U1A接成比较器，比较烙铁芯的热电偶电压和控制电压的大小（对应200～350℃的温度，T12的电压范围应该在5.x mV至10 mV之间，电路通过VR、R2、R3提供同样范围的电压给2脚以供比较）。

3脚电压小于2脚时，1脚输出低电平，C3通过U1A、D2放电，MOS管导通，烙铁芯继续加热；反之则停止加热。

调整VR1就可以调整烙铁芯的温度。

如果您用的元件参数有点“离散”，那么有可能无论电位器怎么调，R3（22Ω）上的电压都超出了这个范围，导致后面的单稳电路状态无法翻转，那么T12只在刚上电的那一下有电压，之后就一直保持无工作电压了。

您可观察LED，是否只在上电时亮了一下后面就不再亮了？如果是，请量一下电位器调到最大时，358的2脚上电压是多少mV（普通数字表的200mV档测就行）？一般只要调整一下R3和R2的取值，或者调一下431的输出电压，就能够正常工作了。

最好是能让电位器调到最小时约400度左右(大约是12mV以下)，电位器最大时温度约180度左右(约5mV)。

计算如下，要求电压在Vmin=5.X，Vmax=10mV，Vr电位器，稳压输出是V，那么R2＝Vmin×Vr/（Vmax-Vmin）,R3=R2×Vmax/V。

计算得出R2、R3的值后，取相近的阻值，再验算。

Vmax=V/(R2+R3)×R3，Vmin=（Vr+R2+R3）×R3。

对于T12的热电耦，11mV以上的电压对应的是4～500℃的高温了，即使能烧到这温度，T12也很快会“玩完”，而且我们平时也不需要这样的温度。

LM324组成的PWM直流电机产生电路它主要由U1（LM324）和Q1组成图4.1中，由U1a、U1d组成振荡器电路，提供频率约为400Hz的方波/三角形波。

U1c产生6V的参考电压作为振荡器电路的虚拟地。

这是为了振荡器电路能在单电源情况下也能工作而不需要用正负双电源。

U1b这里接成比较器的形式，它的反相输入端(6脚)接入电阻R6、R7和VR1，用来提供比较器的参考电压。

这个电压与U1d的输出端(14脚)的三角形波电压进行比较。

当该波形电压高于U1b 的6脚电压．U1b的7脚输出为高电平；反之，当该波形电压低于U1b的6脚电压，U1b的7脚输出为低电平。

由此我们可知，改变U1b的6脚电位使其与输入三角形波电压进行比较。

就可增加或减小输出方波的宽度，实现脉宽调制(PWM)。

电阻R6、R7用于控制VR1的结束点，保证在调节VR1时可以实现输出为全开(全速或全亮)或全关(停转或全灭)，其实际的阻值可能会根据实际电路不同有所改变。

图4.1中，Q1为N沟道场效应管，这里用作功率开关管(电流放大)，来驱动负载部分。

前面电路提供的不同宽度的方波信号通过栅极(G)来控制Q1的通断。

LED1的亮度变化可以用来指示电路输出的脉冲宽度。

C3可以改善电路输出波形和减轻电路的射频干扰(RFI)。

D1是用来防止电机的反电动势损坏Q1。

当使用24v的电源电压时，图1电路通过U2将24V转换成12V供控制电路使用。

而Q1可以直接在21v电源上，对于Q1来讲这与接在12v电源上没有什么区别。

参考图1，改变J1、J2的接法可使电路工作在不同电源电压(12V或24V)下。

当通过Q1的电流不超过1A时，Q1可不用散热器。

但如果Q1工作时电流超过1A时，需加装散热器。

如果需要更大的电流（大于3A），可采用IRFZ34N等替换Q1。

更换大功率场效应管，如IRF360等可驱动10A以上直流电机。

图4.1 LM324组成的PWM直流电机产生原理图工作原理脉冲宽度调制（PWM）是英文“Pulse Width Modulation”的缩写，简称脉宽调制。