一、名词解释1.点火提前角从火花塞跳火时到活塞行至上止点时，曲轴转过的角度，称为点火提前角。2.过量空气系数燃烧1千克的燃油实际供给的空气质量与理论上完全燃烧1千克燃油需要的空气质量之比。3.闭环控制闭环控制是通过对输入信号的检测并利用反馈信号，对输入进行调整使输出满足要求，如在排气管上加装氧化感应，根据排气中的含氧量来测定空燃比，把信号反馈到微机与设定的信号比较对燃油进行修正，使空燃比在所设定值附近。4.增压技术增压技术是利用增压将空气或可燃混合气在进入汽缸前进行压缩以提高进气压力，增大进气密度，增加进气量，是提高功率的技术。曲轴箱强制通风：在发动机工作时，会有部分可燃混合气和燃烧产物经活塞环由汽缸窜入曲轴箱内。当发动机在低温下运行时还可能有液态燃油漏入曲轴箱就是防止曲轴箱气体排放到大气中的净化装置。5.废气再循环废气再循环将部分废气从排气管直接引进气管，与新鲜混合气一道进入燃烧室降低燃烧温度、抑制NOX生成的一种方法。6.冷却水大循环路线水泵→分水管→汽缸水套→汽缸盖水套→节温器（主阀打开、侧阀关闭）→上进水管→散热器→下出水管→水泵。二、填空题1.汽油机燃烧过程分为（着火延迟期）、（速燃期）和（后燃期）三个阶段，柴油机燃烧过程则较其多了（缓燃期）。2.汽油牌号按其（辛烷值）划分，汽油机压缩比越（大），选用的汽油牌号应越（高）。3.点火提前角过（大），易发生爆震。所以，当发生爆震时，可通过（减小）点火提前角来抑制爆震。4.随着转速的升高，汽油机点火提前角自动调节装置使点火提前角（变大）。5.电控汽油喷射系统由（空气供给装置）、（燃油供给装置）和电子控制系统组成。电子控制系统由电控单元、（传感器）和（执行器）组成。6.安装在发动机排气管上的（氧传感器）把信号送给微机，使其对（燃油喷油量）进行修正，使可燃混合气空燃比始终稳定在理论混合比附近。7.汽油机功率大小的调节是通过改变（节气门）的开度，从而改变进入汽缸内的（混合气浓度）来实现的，所以称之为量调节。8.柴油机燃油系统中有三对精密偶件，它们是（喷油器）、出油阀偶件、（柱塞）。9.柴油机喷油器分为（轴针式）和（孔式）两种，前者用在（分隔）式燃烧室，后者用在（统一）式燃烧室。车用柴油机燃烧室一般为（直接喷射）式。10.柱塞副的滑动性实验方法：将柱塞套倾斜（45°~60°）左右，拉出柱塞全行程的（1/3）左右，放手后，柱塞在自重的作用下（缓慢）地进入套筒内。11.柴油机调速器的作用是在柴油机负荷改变时，自动的改变（供油量）来维持其转速稳定。12.按润滑油供给方式不同，车用发动机的润滑方式有（飞溅润滑）、（压力润滑）和润滑脂润滑，其中主轴颈的润滑属于（压力）润滑，活塞、汽缸的润滑属于（飞溅）润滑。13.发动机正常工作时，机油进入燃烧室的途径是（窜气）和（泵油）。14.汽油机的主要有害排放物是（CO）、（HC）和（NOX），柴油机的主要有害排放物是（NOX）和（炭烟）。15.可变进气岐管系统式发动机在高速时采用（短）的进气岐管，中、低速时采用（长）的进气岐管，以充分利用气流的惯性效应、提高充气效率。16.机油泵分（齿轮）式和（转子）式两种。17.机油（粗）滤器与主油道串联，滤清后的机油流入主油道；而（细）滤器与主油道并联，滤清后的机油直接流回油底壳。三、判断题（正确打√、错误打×）1.汽油机理论混合气的空燃比等于12.8。（×）2.汽油机在低速、大负荷时易发生爆燃。（√）3.由于有气门叠开期，所以“回火”现象在柴油机和汽油机上都可能发生。（×）4.点火提前角过小，是引起发动机过热、排气管放炮的原因之一。（√）5.电控汽油喷射发动机中，只要某一传感器出故障，发动机既不能正常工作。（×）6.热线式空气流量计，在每次停机时，发动机ECU仍会给其供电1~2s，以使白金热线产生高温，烧去污物。（√）7.减少着火延迟期内喷入的柴油量，可以减轻柴油的工作粗暴。（√）8.喷油压力可通过调节喷油器调压弹簧的预紧力来改变。（√）9.纸质干式空气滤清器经油浸润后，滤清效率提高，发动机性能得到改善。（√）10.分配式喷油泵较柱塞式喷油泵体积小，零件少，便于维修。其各缸供油的均匀性较好。（√）11.当润滑系中粗滤器发生堵塞时，机油即不能进入主油道。（×）12.两极式调节器仅在柴油机最高和最低转速时起作用，以防止飞车和怠速不稳，而在中间转速时不起作用。（√）13.发动机工作温度过高时，应立即打开散热器盖，加入冷水。（×）14.水泵、风扇的转动都是通过传动皮带由曲轴驱动的。（×）15.润滑油不仅有减小运动副摩擦、磨损的作用，而且具有冷却、清洁、密封、防锈的作用。（√）16.不管是化油器式汽油机还是电控喷射式汽油机，都是由节气门来控制进气量的。（√）17.化油器中的主供油装置除了在怠速和极小负荷工况外，其他工况均参与工作。（√）18.车用柴油机按凝点划分牌号。（√）19.曲轴箱强制通风在改善排放的同时，使曲轴箱内的压力升高。（×）20.风扇工作时，风向散热器方向吹，以利于散热。（×）四、单项选择题1.EGR废气在循环系统的功用是（B）。A．对废气中的能量进行再利用B．抑制NOX的生成量C．抑制CO的生成量D．抑制HC的生成量2.调整柱塞式喷油泵滚轮体的调整螺钉或调整垫块，可以（C）。A．改变各分泵的供油提前角及各分泵的供油间隔角度B．改变供油压力C．改变循环供油量D．改变各分泵的有效行程3.柴油机供油提前角自动调节装置的作用，是在柴油机转速升高时（A）。A．自动增大喷油泵供油提前角B．自动减小喷油泵供油提前角C．使喷油量泵供油提前角不变化D．以上都不对4.对喷油泵供油量不均匀度的要求是（A）A. 怠速和额定均不大于3﹪B. 怠速和额定均不大于30﹪C. 怠速不大于30﹪D. 额定不大于30﹪5.喷油嘴针阀磨损后，容易造成（A）。A．喷油量增大B．喷油量减少C．喷油提前D．喷油压力增大6．曲轴主轴承径向间隙太大将导致（D）。A．油压过高B．润滑油变质C．机油消耗异常D．油压过低7．以下哪个零部件是过同改变流经散热器的冷却水流量来调节冷却强度的？（C）。A．水箱盖B．百叶窗C．节温器D．风扇离合器8．以下哪个不是空气滤清器脏后的现象？（C）。A．发动机无力B．排气冒黑烟C．冷却液温度升高D．较少燃油消耗9．柴油机工作粗暴，可能的原因是（B）。A．点火过早或过迟B．喷油时间过早或过迟C．喷油雾化不良D．发动机工作温度过高10.蜡式节温器中的蜡泄漏时，会使（B）。A．水流只能进行大循环B．水流只能进行小循环C．大、小循环都不能进行D．大、小循环都能进行11.下列哪一项不是润滑系统的零部件？（D）。A．机油泵B．机油滤清器C．旁通阀D．节温器12.下列哪一项不是冷却系统的作用？（B）。A．从发动机带走多余的热量B．保持发动机温度尽可能低C．使发动机尽快达到工作温度D．保护发动机内部零件不过热13.下列哪一项不是冷却系统的零部件？（C）。A．水箱B．风扇离合器C．空气滤清器D．节温器14.下列哪一项不是汽油机燃油系中的零部件？（D）。A．燃油泵B．燃油滤清器C．燃油箱D．催化转化器15.过量空气系数为（B）的混合气为经济混合气。A．0.6~0.8B．1.05~1.15C．0.85~0.95D．0.7左右五、简答题1、说明汽油机各工况对混合气浓度的要求。答：（１）稳定工况（发动机热态无转速或负荷的实然变化）怠速工况a＝０.６～０.８小负荷工况a＝０.７～０.９中等负荷工况a=1.05~1.15大负荷工况：供给功率混合气a＝０.８５～０.９５（２）过渡工况：①冷启动：要求供给极浓混合气a＝０.２～０.６以确保发动机能顺利启动。②暖启动：要求供给混合气a值应当随着温度升高，从启动时极小值逐渐加大到稳定怠速时需要的a值。③要求额外增加燃油使发动机具有良好的加速性能。２、燃油压力调节器的作用是什么？答：燃油压力调节器的作用是保持发动机在任何工作情况下燃油系统的油压与进气管的压力差值一定只有恒定时，ＥＣＵ才能通过控制喷油持续时间来准确控制喷油量。３、何谓爆震？有何外部特征？答：在正常火焰到达之前自然出现一个或多个或多个火焰中心迅速将未端混合气燃烧使缸内局部压力大大升高，形成爆炸势冲击波。４、如何排除燃油系气阻？答：松开油管接头、打马达，使马达工作直到流出液体汽油。________________________________________________________________________________________art________________________________

请您务必删除一下内容， O( ∩ _ ∩ )O 万分谢谢！！！ 2015 年中央电大期末复习考试小抄大全，电大期末考试必备小抄，电大考试必过小抄 Indonesia has emerged as a top vacation destination for Chinese this summer, along with Thailand's Phuket island and the Maldives archipelago. Encouraged by growth in Chinese travelers to Indonesia, the government in Jak a has recently relaxed its visa policy. Since June 10, Chinese tourists can enter Indonesia through nine appointed locations, including the Soekarno Hatta International Airport in Jakarta, the Ngurah Rai International Airport in Bali and the Kuala Namu International Airport in Medan, by just getting their passports stamped on arrival. Officially, it is called the "free-visa" scheme. The new policy also means Chinese tourists can save $35 on visa fees, which will likely make trips to Indonesia more alluring. While such an arrangement allows Chinese visitors to stay up to 30 days for the purpose of traveling, those seeking extensions will need to get paid visas from that country's missions inBeijing, Shanghai, Guangzhou or Hong Kong, according to an official at the Indonesia embassy in Beijing. Santo Darmosumarto, head of the embassy's information, social and cultural section, says the new policy is aimed at strengthening people-to-people contacts between the two countries. Dai Yu, marketing director of Ctrip, a major Chinese online travel agency, says: "We've seen a nearly 50 percent growth over the previous month in the number of Chinese tourists to Bali since the policy was announced." During his trip to China in March, Indonesian President Joko Widodo proposed that his country and China aim to increase two-way visits to a maximum of 10 million people in the next few years. The Indonesian government has set their sights on greeting 2 million Chinese tourists by the end of this year, according to the official. "The Indonesian government hopes that Indonesian nationals would also be given preferential treatment while visiting China," says Darmosumarto. In 2013, the number of Chinese tourists who visited Indonesia stood around 807,000. Last year, it increased to 959,000, he adds. Bali remains the most popular site among Chinese tourists. In February, more than 92,200 Chinese tourists made trips to Bali, ranking first among overseas visitors, the Bali Times reported. Last year, the island witnessed more than 586,000 arrivals from China, an increase of 51 percent over 2013. "Bali isn't just for sightseeing, but also for weddings, honeymoons, golf and many outdoor activities," says Fan Wenqing, a marketing executive at Garuda, Indonesia's national airliner. Garuda offers three nonstop flights between Beijing and Bali, and four each week between Beijing and Jakarta. There are daily flights from Guangzhou, in Guangdong province, and Shanghai to Jakarta as well. It takes from six to eight hours on a nonstop flight to reach Indonesia from China. Indonesia is home to more than 17,000 islands. Tourists can tour Yogyakarta to see Prambanam and Borobudur, two historical and religious sites, and explore the local handicraft markets. The base of a volcano, Bandung, which is also known as the "Paris of Java", is ideal for adventure-seekers. Many ecotourism destinations, such as Toba Lake in Sumatra, Tanjung Puting National Park in Kalimantan and Bunaken in Manado, are places the embassy official recommends for tourists. Indonesia boasts world-class surfing facilities along the shores of Sumatra down to Nusa Tenggara Islands. Recently, Lombok, a sister island east of Bali has gotten so much attention from Chinese travelers that some travel agencies are offering twin packages for Bali and Lombok. The best time to visit Bali is from May to October, when it doesn't rain much and the weather is cool. At press time, a weeklong package from Shanghai or Guangzhou to Bali was a little more than 3,000 yuan ($480) on Ctrip's website. Chinese tourists have taken a shine to rafting in Ubud, sightseeing in Tanah Lot, and surfing and diving in Nusa Lembongan, says Dai. Civet coffee, essential oil and woodcarvings are among the most popular products for Chinese tourists in Indonesia, she says. Indonesian food is also something that visitors shouldn't miss. Local cuisines feature many spices, including peppers and cloves, and coconut pulp. Fried rice, "dirty duck" and roast suckling pig are recommended. Children's illustration books first appeared in the 1600s in Europe. Their passage to China, however, took much longer, roughly 300 years. In China, children's illustration books have a history of just 100 years and their development can be divided into four stages. From early 1900s to mid 1900s, a large number of books and magazines with illustrations appeared with the fast development of the modern publishing industry. The illustration arts at that time were a mixed genre of Chinese traditional paintings and the western style, and most of the stories originate from the fundamental changes that China experienced after the collapse of Qing Dynasty (1644-1911), the warlord struggles and the war against the Japanese invasion. The second stage was from mid 1900s to late 1970s, when the "cultural revolution" (1966-76) ended. The fast development of some special publishing houses for children gave birth to a large number of illustration-story books, which made a good use of folk art techniques, such as wood board carving, frescoes, and ink and wash painting, etc. Many of the popular stories are from Chinese history and wars after 1900s. The third stage is from early 1980s to late 1990s, a golden period for the development of children's illustration books. The reform and opening-up brought in new concepts and ideas from the West to China, a country that had been closed to the West for nearly three decades. Fast development of economy, society and culture provided the writers and painters with a lot of inspiration to create new literature works and draw illustrations. China also imported large amounts of children's illustration books from the West and Japan. Many young parents in China have a strong nostalgia about children's illustration books they read in the 1980s and 1990s. This is also the last era in China's artistic innovation before the advent of the Internet period. The fourth stage is featured with the spread of the Internet and the other computerized means of art innovation. The hand-drawn children's illustration books are gradually replaced by cartoons drawn and copied by software and machines, and shown on tablets, computers, television and smart phones, instead of books. Hainan Tropical Wildlife Park and Botanical Garden is nature's haven, with no less than 4,000 rare birds and animals representing 200 species. With tropical forest covering over 90 percent of its area, the garden offers beautiful views of a wide range of tropical plants, flowers and fruit trees. The scenic spot about 25 kilometers from the center of Haikou offers a drive-thru safari tour where you can get up close with elephants, lions and bears. The "Safari on Foot" area features walking trails where visitors can see the rest of the animals, including hippos and monkeys, and feed them for a small fee. Visitors also can see what happens when you breed a lion and a tiger. Two unique attractions are rare hybrids: a liger, the offspring of a mallion and a female tiger and a tigon, which is created by a female lion and a male tiger. As a teaching center of the National Popular Science Education program, the park also serves as a second classroom for students to learn about wildlife and plants. Since it was established in 1995, it has received more than one million student visitors. At a crucial moment when pessimism has brought the Greek crisis to such a head that the country is closer to a default on its debt repayments than ever, Li offered a spark of enthusiasm to restart the stalled talks by calling on Greece and its creditors to reach a last-minute deal that will allow Greece to remain in the eurozone. Given the escalation of the country's crisis over the weekend sent a shock wave through the global stock markets on Monday, there are ample reasons to worry about the uncertainties surrounding the events in Greece and the effect a default would have on Europe, relations between China and the EU, global financial stability and the nascent global economic recovery. Greece has announced that it will hold a referendum on a bailout plan proposed last week by the country's creditors. In response, Greece's eurozone partners have refused to extend the country's bailout program and the European Central Bank capped its emergency support for the country's banks. A real danger now looms of Greece exiting the euro, which might derail the global economic recovery and damage the long-term viability of the euro as a currency. However, such a tragedy is neither certain nor unavoidable. The EU should shoulder its responsibility to prevent the Greek crisis from overshadowing the fragile global recovery. As a major customer and supplier of the 28-nation EU, and a responsible long-term holder of Eurobonds, China's confidence in and commitment to a strong eurozone offers EU leaders the necessary support to look at the Greek crisis from a broader and longer perspective. When Li said that China will not only consider a China-EU investment platform to back European Commission President Jean-Claude Juncker's plan to revive the European economy, but also buy more bonds issued by the European Investment Bank, EU leaders should be clear that China wants to see the EU maintain its integrity and a forward trajectory. Such a confidence-building effort is particularly valuable, especially from such a large country as China which already has a huge stake and seeks to further expand it in a strong eurozone. It will be a tragedy to allow inaction over the Greek crisis to stand in the way of growth-boosting Sino-EU cooperation. Like a shining pearl, West Lake is the symbol of Hangzhou city. From ancient times, many poems have praised the amazing scenery of the lake. At the very beginning, the West Lake was a part of the Qiantang River. In the year 822, Bai Juyi, a famous poet and an officer of the Tang Dynasty (AD 618-907), suggested to build a stronger causeway to store water so that the lake was doubled in size. And during the Song Dynasty (AD 960-1279), many temples and pagodas were built due to a Buddhist revival, and the look of West Lake was formed at that time. The West Lake is quite big and features different classic views from different locations. Technically, there are ten scenes which were marked by Emperor Qianlong with four-character inscriptions 200 years ago, such as the Melting Snow on the Broken Bridge and Sunset Glow over Leifeng Pagoda.