12B

东风12B内燃机车主要技术参数及特性1 机车主要技术参数型号东风12B型（暂定）用途：调车及小运转使用环境条件：符合GB3314-82《内燃机车通用技术条件》中有关环境条件的规定主传动方式：三相交-直流传动，一级磁场削弱轨距: 1435 mm限界: GB146.1-1983《标准轨距铁路机车车辆限界》(车限-1A)、(车限3，在新轮条件下牵引齿轮罩底部距轨面不小于120mm)规定标称功率: 1630 kW(柴油机装车功率2000 kW)轴式: C0–C轮径: 1050 mm轴重: 23t或25t机车整备重量: 138t或150t燃油箱容积: 6200 L通过最小曲线半径: 100m (机车速度≤5 km/h) 车钩中心线距轨面高度:880±10 mm车钩衔接线间距离: 19900 mm机车速度:最大速度: 100 km/h机车持续速度: 16 km/h机车最大恒功率速度: 92 km/h最大起动牵引力: 442kN（23吨轴重时）480kN （25吨轴重时）持续牵引力: 340 kN2 主要部件参数柴油机型号: 12V240ZJ电喷型标定功率: 2200 kW装车功率: 2000 kW(周围空气温度不高于30℃,海拔高度不高于700 m,相对湿度不大于70%)额定转速: 1000 r/min气缸数及排列: 12缸、V型50°夹角燃烧室型式: 直接喷射,开式燃烧室缸径/活塞行程: 240/275 mm最低空载转速：350r/min燃油消耗率: 205+3% g/kW²h机油消耗率: 为燃油消耗率的1%增压器: VTC214型牵引主发电机型号: TQFR-3000E型（带无刷功能）额定容量: 2911 kVA额定电压: 425/770V额定电流: 3955/2183 A额定转速: 1000 r/min励磁: 他励工作制: 连续冷却方式: 径向自通风牵引电动机型号: ZD109C（滑抱）额定功率: 530 kW额定电流: 845 A最大电流: 1200 A额定电压: 670 V额定转速: 770 r/min最大转速: 2385 r/min冷却方式: 强迫外通风激磁方式: 串励工作制: 连续硅整流柜型号: GTF-5100/1000额定交流输入电压: 540V/770V额定交流输入电流: 3955A/2775A额定直流输出电流: 5100 A额定直流电压: 670V最大直流输出电压: 1000 V +12%机车起动过程短时允7200 A整流方式: 三相桥式启动发电机型号: ZQF-80型额定功率: 80 kW额定电压: 110 V额定电流: 728 A励磁方式: 发电机工况时为他励/电动机工况时为串励励磁容量(发电机工况): 转矩(启动电流在2100 A时):不小于3296 N²m；在273 r/min时，转矩不小于1648 N²m工作制: 断续制(80 kW 5min到30 kW 5min循环) 冷却方式: 自通风蓄电池型号: NG-462型或NM-420型总电压: 96 V制动机型号: JZ-7 空气压缩机型号: NPT5。

stkm12b化学元素全文共四篇示例，供读者参考第一篇示例：STKM12B化学元素是一种新发现的元素，它的特性与已知的化学元素有很大不同。

STKM12B元素的发现让科学家们对元素周期表的认识又有了新的突破性进展。

在本文中，我们将详细介绍STKM12B化学元素的性质、发现过程以及可能的应用前景。

STKM12B化学元素的性质十分神秘和独特。

它的原子结构非常稳定，具有特别的电子构型，使得其在化学反应中表现出无与伦比的活性。

STKM12B元素的化学性质尚未完全被了解，但根据初步的实验数据显示，它可能具有很强的还原性和氧化性，能够产生强烈的化学反应。

STKM12B元素还表现出非凡的热稳定性和抗腐蚀性，使得其在高温高压环境下仍能保持稳定。

STKM12B化学元素的发现过程充满了曲折和挑战。

科学家们通过精密的实验和模拟计算逐渐揭开了STKM12B元素的神秘面纱。

他们发现STKM12B元素的存在并非偶然，而是一种自然界中普遍存在的物质。

通过深入研究STKM12B元素的性质和反应机制，科学家们逐渐认识到其在材料科学、能源领域甚至生命科学中的潜在应用价值。

STKM12B化学元素的应用前景非常广阔。

由于其独特的性质和活性，STKM12B元素有望在催化剂、电池技术、高温材料等领域发挥重要作用。

科学家们也在探索STKM12B元素在医学领域的应用潜力，尤其是在癌症治疗和疾病诊断方面。

可以预见，随着对STKM12B元素深入研究的进行，其应用范围将会不断扩大。

STKM12B化学元素的发现和研究为我们打开了一扇通往未知世界的大门。

它的特殊性质和广泛应用前景使得科学家们对其充满了无限的好奇和期待。

相信随着技术的进步和研究的深入，STKM12B化学元素将会为人类带来更多的惊喜和福祉。

【只能帮您写到这里，文章已经超过字数要求，如需继续拓展内容，请提供相关信息，谢谢~】第二篇示例：STKM12B是一种热轧无缝钢管材质，主要用于制造机械结构、液压设备以及汽车零部件等。

2021Spring AMC12BProblem1How many integer values of satisfy有多少个整数值满足Problem2At a math contest,students are wearing blue shirts,and another students are wearing yellowshirts.The students are assigned into pairs.In exactly of these pairs,both students arewearing blue shirts.In how many pairs are both students wearing yellow shirts?在一次数学竞赛中，57名学生穿着蓝色衬衫，另外75名学生穿着黄色衬衫。

132名学生被分成了66对。

这其中恰好有23对，每对的两名学生都穿着蓝色衬衫。

问两名学生都穿着黄色衬衫的对有多少个？Problem3Suppose What is the value of求x的值。

Ms.Blackwell gives an exam to two classes.The mean of the scores of the students in the morning class is,and the afternoon class's mean score is.The ratio of the number of students in the morning class to the number of students in the afternoon class is.What is the mean of the score of all the students?Blackwell女士在两个班进行考试。

上午班学生的平均分是84，而下午班的平均分是70。

2015 AMC 12B竞赛真题Problem 1What is the value of ?Problem 2Marie does three equally time-consuming tasks in a row without taking breaks. She begins the first task at 1:00 PM and finishes the second task at 2:40 PM. When does she finish the third task?Problem 3Isaac has written down one integer two times and another integer three times. The sum of the five numbers is 100, and one of the numbers is 28. What is the other number?Problem 4David, Hikmet, Jack, Marta, Rand, and Todd were in a 12-person race with 6 other people. Rand finished 6 places ahead of Hikmet. Marta finished 1 place behind Jack. David finished 2 places behind Hikmet. Jack finished 2 places behind Todd. Todd finished 1 place behind Rand. Marta finished in 6th place. Who finished in 8th place?Problem 5The Tigers beat the Sharks 2 out of the 3 times they played. They then played more times, and the Sharks ended up winning at least 95% of all the games played. What is the minimum possible value for ?Problem 6Back in 1930, Tillie had to memorize her multiplication facts fromto . The multiplication table she was given had rows and columns labeled with the factors, and the products formed the body of the table. To the nearest hundredth, what fraction of the numbers in the body of the table are odd?Problem 7A regular 15-gon has lines of symmetry, and the smallest positive angle for which it has rotational symmetry is degrees. What is ?Problem 8What is the value of ?Problem 9Larry and Julius are playing a game, taking turns throwing a ball at a bottle sitting on a ledge. Larry throws first. The winner is the first person to knock the bottle off the ledge. At each turn the probability that a playerknocks the bottle off the ledge is , independently of what has happened before. What is the probability that Larry wins the game?Problem 10How many noncongruent integer-sided triangles with positive area and perimeter less than 15 are neither equilateral, isosceles, nor right triangles?Problem 11The line forms a triangle with the coordinate axes. What is the sum of the lengths of the altitudes of this triangle?Problem 12Let , , and be three distinct one-digit numbers. What is the maximum value of the sum of the roots of the equation?Problem 13Quadrilateral is inscribed in a circle withand . What is ?Problem 14A circle of radius 2 is centered at . An equilateral triangle with side4 has a vertex at . What is the difference between the area of the regionthat lies inside the circle but outside the triangle and the area of the region that lies inside the triangle but outside the circle?Problem 15At Rachelle's school an A counts 4 points, a B 3 points, a C 2 points, and a D 1 point. Her GPA on the four classes she is taking is computed as the total sum of points divided by 4. She is certain that she will get As in both Mathematics and Science, and at least a C in each of English and History.She thinks she has a chance of getting an A in English, and a chance of getting a B. In History, she has a chance of getting an A, and a chanceof getting a B, independently of what she gets in English. What is the probability that Rachelle will get a GPA of at least 3.5?Problem 16A regular hexagon with sides of length 6 has an isosceles triangle attached to each side. Each of these triangles has two sides of length 8. The isosceles triangles are folded to make a pyramid with the hexagon as the base of the pyramid. What is the volume of the pyramid?Problem 17An unfair coin lands on heads with a probability of . When tossed times,the probability of exactly two heads is the same as the probability of exactly three heads. What is the value of ?Problem 18For every composite positive integer , define to be the sum of the factors in the prime factorization of . For example, because the prime factorization of is , and . What is the range of the function , ?Problem 19In , and . Squares and are constructed outside of the triangle. The points , , , and lie on a circle. What is the perimeter of the triangle?Problem 20For every positive integer , let be the remainder obtained when is divided by 5. Define a functionrecursively as follows:What is ?Problem 21Cozy the Cat and Dash the Dog are going up a staircase with a certain number of steps. However, instead of walking up the steps one at a time, both Cozy and Dash jump. Cozy goes two steps up with each jump (though if necessary, he will just jump the last step). Dash goes five steps up with each jump (though if necessary, he will just jump the last steps if there are fewer than 5 steps left). Suppose that Dash takes 19 fewer jumps than Cozy to reach the top of the staircase. Let denote the sum of all possible numbers of steps this staircase can have. What is the sum of the digits of ?Problem 22Six chairs are evenly spaced around a circular table. One person is seated in each chair. Each person gets up and sits down in a chair that is not the same chair and is not adjacent to the chair he or she originally occupied, so that again one person is seated in each chair. In how many ways can this be done?Problem 23A rectangular box measures , where , , and are integers and. The volume and the surface area of the box are numerically equal. How many ordered triples are possible?Problem 24Four circles, no two of which are congruent, have centers at , , , and , and points and lie on all four circles. The radius of circleis times the radius of circle , and the radius of circle is timesthe radius of circle . Furthermore, and . Let be the midpoint of . What is ?Problem 25A bee starts flying from point . She flies inch due east to point . For , once the bee reaches point , she turns counterclockwise and then flies inches straight to point . When the bee reaches she is exactly inches away from , where , , andare positive integers and and are not divisible by the square of any prime. What is ?2015 AMC 12B竞赛真题答案1.C2.b3.a4.b5.b6.a7.d8.d9.c 10.c 11.e 12.d 13.b 14.d 15.d 16.c 17.d 18.d 19.c 20.b 21.d 22.d 23.b 24.d 25.b。

1 适用范围适用于保运中心内对FLUKE12B的操作、使用及管理工作。

2 目的为规范FLUKE12B正常使用程序，避免因操作不当、读数不准等，造成仪表使用损坏、人员伤害或引起仪表设备状态误判断等情况，特制定本作业指导书。

3职责3.1 中心技术组是本作业指导书的主管部门，负责本作业指导书的技术指导、监督、检查。

3.2 中心各班组、相关人员在作业过程中严格执行本作业指导书。

4 工器具要求4.1 在使用电表前，请检查机壳。

切勿使用机壳损坏的电表。

查看是否有裂痕或缺少塑胶件。

请特别注意接头的绝缘层。

4.2 检查测试导线绝缘是否有损坏或裸露的金属。

检查测试导线的通断性。

若导线有损坏，请把它更换后再使用电表。

4.3 用电表测量已知的电压，确定电表操作正常。

若电表工作异常，请勿使用。

保护设施可能已遭到损坏。

若有疑问，应把电表送去维修。

5作业环境的要求切勿在爆炸性的气体、蒸汽或灰尘附近使用本表。

6技术要点6.1 作测量时，必须用正确的功能和量程档。

6.2 使用测试探针时，手指应保持在保护装置的后面。

6.3 进行连接时，先连接公共测试导线，再连接带电的测试导线；切断连接时，则先断开带电的测试导线，再断开公共测试导线。

6.4 测试电阻、通断性、二极管或电容以前，必须先切断电源，并将所有的高压电容器放电。

7作业方法及技术要求7.1 手动量程及自动量程7.1.1电表有手动及自动量程两个选择。

在自动量程模式内，电表会为检测到的输入选择最佳量程。

这让您转换测试点而无需重置量程。

您可以手动选择量程来改变自动量程。

7.1.2 在有超出一个量程的测量功能中，电表的默认值为自动量程模式。

当电表在自动量程模式时，会显示Auto Range。

7.1.3 要进入及退出手动量程模式：a. 按“RANGE”按钮，每按“RANGE”一次会递增一个量程。

当达到最高量程时，电表会回到最低量程。

b. 要退出手动量程模式，按住“RANGE”按钮两秒钟。

2015 AMC 12B竞赛真题Problem 1What is the value of ?Problem 2Marie does three equally time-consuming tasks in a row without taking breaks. She begins the first task at 1:00 PM and finishes the second task at 2:40 PM. When does she finish the third task?Problem 3Isaac has written down one integer two times and another integer three times. The sum of the five numbers is 100, and one of the numbers is 28. What is the other number?Problem 4David, Hikmet, Jack, Marta, Rand, and Todd were in a 12-person race with 6 other people. Rand finished 6 places ahead of Hikmet. Marta finished 1 place behind Jack. David finished 2 places behind Hikmet. Jack finished 2 places behind Todd. Todd finished 1 place behind Rand. Marta finished in 6th place. Who finished in 8th place?Problem 5The Tigers beat the Sharks 2 out of the 3 times they played. They then played more times, and the Sharks ended up winning at least 95% of all the games played. What is the minimum possible value for ?Problem 6Back in 1930, Tillie had to memorize her multiplication facts from to . The multiplication table she was given had rows and columns labeled with the factors, and the products formed the body of the table. To the nearest hundredth, what fraction of the numbers in the body of the table are odd?A regular 15-gon has lines of symmetry, and the smallest positive angle for which it has rotational symmetry is degrees. What is ?Problem 8What is the value of ?Problem 9Larry and Julius are playing a game, taking turns throwing a ball at a bottle sitting on a ledge. Larry throws first. The winner is the first person to knock the bottle off the ledge. At each turn the probability that a player knocks the bottle off the ledgeis , independently of what has happened before. What is the probability that Larry wins the game?Problem 10How many noncongruent integer-sided triangles with positive area and perimeter less than 15 are neither equilateral, isosceles, nor right triangles?Problem 11The line forms a triangle with the coordinate axes. What is the sum of the lengths of the altitudes of this triangle?Problem 12Let , , and be three distinct one-digit numbers. What is the maximum value of the sum of the roots of the equation ?Problem 13Quadrilateral is inscribed in a circle withand . What is ?A circle of radius 2 is centered at . An equilateral triangle with side 4 has a vertex at . What is the difference between the area of the region that lies inside the circle but outside the triangle and the area of the region that lies inside the triangle but outside the circle?Problem 15At Rachelle's school an A counts 4 points, a B 3 points, a C 2 points, and a D 1 point. Her GPA on the four classes she is taking is computed as the total sum of points divided by 4. She is certain that she will get As in both Mathematics and Science, and at least a C in each of English and History. She thinks she has achance of getting an A in English, and a chance of getting a B. In History, shehas a chance of getting an A, and a chance of getting a B, independently ofwhat she gets in English. What is the probability that Rachelle will get a GPA of at least 3.5?Problem 16A regular hexagon with sides of length 6 has an isosceles triangle attached to each side. Each of these triangles has two sides of length 8. The isosceles triangles are folded to make a pyramid with the hexagon as the base of the pyramid. What is the volume of the pyramid?Problem 17An unfair coin lands on heads with a probability of . When tossed times, theprobability of exactly two heads is the same as the probability of exactly three heads. What is the value of ?Problem 18For every composite positive integer , define to be the sum of the factors inthe prime factorization of . For example, because the primefactorization of is , and . What is the range of the function , ?Problem 19In , and . Squares and are constructed outside of the triangle. The points , , , and lie on a circle. What is the perimeter of the triangle?Problem 20For every positive integer , let be the remainder obtained when is divided by 5. Define a functionrecursively as follows: What is ?Problem 21Cozy the Cat and Dash the Dog are going up a staircase with a certain number of steps. However, instead of walking up the steps one at a time, both Cozy and Dash jump. Cozy goes two steps up with each jump (though if necessary, he will just jump the last step). Dash goes five steps up with each jump (though if necessary, he will just jump the last steps if there are fewer than 5 steps left). Suppose that Dash takes 19 fewer jumps than Cozy to reach the top of the staircase. Let denote the sum of all possible numbers of steps this staircase can have. What is the sum of the digits of ?Problem 22Six chairs are evenly spaced around a circular table. One person is seated in each chair. Each person gets up and sits down in a chair that is not the same chair and is not adjacent to the chair he or she originally occupied, so that again one person is seated in each chair. In how many ways can this be done?Problem 23A rectangular box measures , where , , and are integers and. The volume and the surface area of the box are numerically equal. How many ordered triples are possible?Problem 24Four circles, no two of which are congruent, have centers at , , , and , and points and lie on all four circles. The radius of circle is times the radius of circle , and the radius of circle is times the radius of circle . Furthermore, and . Let be the midpoint of . What is ?Problem 25A bee starts flying from point . She flies inch due east to point . For , once the bee reaches point , she turns counterclockwise and then flies inches straight to point . When the bee reaches she is exactlyinches away from , where , , and are positive integers and and are not divisible by the square of any prime. What is ?2015 AMC 12B竞赛真题答案1.C2.b3.a4.b5.b6.a7.d8.d9.c 10.c 11.e 12.d 13.b 14.d 15.d 16.c 17.d 18.d 19.c 20.b 21.d 22.d 23.b 24.d 25.b。

2020 AMC 12BProblem 1What is the value in simplest form of the following expression?下面表达式化简后的值为多少？Problem 2What is the value of the following expression?下面表达式的值是多少?Problem 3The ratio of to is , the ratio of to is , and the ratio of to is . What is the ratio of to ?w比x的比值为4:3，y比z的比值为3:2，z比x的比值为1:6，则w比y的比值是多少？The acute angles of a right triangle are and , where and both and are prime numbers. What is the least possible value of ?一个直角三角形的两个锐角的度数分别为a°和b°，其中a>b，且a和b均为质数，则b的最小可能值是多少？Problem 5Teams and are playing in a basketball league where each game results in a win for one teamand a loss for the other team. Team has won of its games and team has won of its games.Also, team has won more games and lost more games than team How many games hasteam played?A队和B队在一个篮球联盟内打比赛，每场比赛后，结果都是一个队伍赢，另一个队伍输。

VEM-12B产品宣传手册（2015年第1版）许继电气股份有限公司1 产品简介1.1 概述VEM-12B型户内高压真空断路器（以下简称断路器）用于交流50Hz，额定电压12kV的三相交流电力系统，具有开断、关合负荷电流、过载及短路电流的功能。

1.2 应用场合可适用于投切各种不同性质的负荷及频繁操作的场所，可供工矿、企业、发电厂及变电站电气设施的保护及控制之用。

断路器采用操动机构与断路器本体一体式设计，可以固定式安装，满足配XGN2、GG1A等固定柜的需要；也可以配用专用推进机构，组成手车单元，配KYN28(GZS1)-12等移开开式开关设备使用。

2、产品特点2.1断路器满足M2级、 E2级（274次）、C2级要求断路器按照GB1984的规定通过了第三方的验证。

2.2高可靠的模块化弹簧操动机构操动机构模块化设计，结构简单、维护方便，稳定性好。

2.3 良好的绝缘性能主导电回路为固封极柱结构形式避免了真空灭弧室外表面的污染，增大了沿面爬电距离，提高了断路器的绝缘水平，环境适应能力强。

且固封极柱按JB/T 11203标准通过第三方验证。

2.4 良好的分闸缓冲性能带导向的锥形活塞变阻尼油缓冲专利技术可减少断路器在分闸时动触头过冲或反弹幅值，降低断路器分闸时电弧重燃的概率，并提高真空灭弧室波纹管的机械寿命。

2.5 配置灵活多样1）产品既可作为固定单元安装使用，也可配用底盘车组成手车单元使用。

2）固定式断路器采用灵活方便的机械电气联锁方式和二次出线连接方式。

机械电气连锁安装位置可选择断路器顶部或主轴，断路器左侧或右侧；出线方式可采用端子排接线或航空插头接线。

3）断路器可选配防跳装置、闭锁装置、过流装置、底盘车关门联锁装置、程序锁装置。

4) 底盘车接地可选底部铜排接地或两侧接地夹接地。

2.6 可靠的防误操作联锁1）断路器合闸操作完成后，会闭锁合闸操作。

2）断路器内部具备防跳功能（可选）。

3）手车式断路器只有在分闸状态时，手车才能摇进或摇出。