聚乙烯装置操作工
NPT是National (American) Pipe Thread的缩写，属于美国标准的55度锥管螺纹。
题目
NPT是National (American) Pipe Thread的缩写，属于美国标准的55度锥管螺纹。
参考答案和解析
相似问题和答案
第1题：
Questions 61-65 are based on Passage Two:
Passage Two
As the 21st century begins, a number of leaders in politics, education, and other professions believe that the US must adopt some new values to go along with the old traditional ones. What new values should Americans adopt? This is a very difficult question to answer. Certainly, a greater value should be placed on the conservation of natural reasources; Americans should learn to use less and waste less. But conservation has never been a strong value to Americans, who have believed that their country offered an endless,abundant supply of natural resources.
Recently, progress has been made-more and more Americans are recycling their paper, cans,bottles,and other goods-but old wasteful habits died hard. Furthermore,the need to protect the environment may conflict with the need for jobs,as in the Northwest ,where conservationists battle lumber companies that want to cut down ancient redwood trees. A belief in the value of conservation is still compared with other American values; it can become stronger only as Americans see the need for it more clearly.
In addition,Americans may need to place a strong value on cooperation on a national scale to achieve important national objectives. The American idea of the national good has never been based on national cooperation but rather on the freedom of the individual, maintaining those conditions that provide the greatest freedom and prosperity for the individual .
It is far more difficult for Americans to accept shared sacrifice for the common good and wellbeing of the entire country. For example ,although the majority of Americans believe that it is extremely important to balance the national budget and reduce the deficit, they do not want to see cuts in government programs that benefit them personaliy.
The American value of competition also hinders the development of a spirit of national cooperation. Competition sometimes encourages feelings of suspicion rather than the mutual trust that is necessary for successful national cooperation. Although Americans often cooperate successfully on the local level-in neighborhood groups and churches, for example, on the national level, they may see themselves as part of an interest group that is competing with other interest groups for government funds. A request by the national government for shared sacrifice may be seen as coercive and destructive rather than voluntary and constructive. However, the demands for the 21st century may compel Americans to place a greater value on national cooperation to solve problems that affect them all, directly and indirectly.
The best TITLE of this passage could be ( ).
A. Which is Better, New Value or Old Value?
B. Conservation vs. Need for Jobs
C. The Need for New National Values
D. Cooperation and Competition
C[解析]文章主要是讲新价值观的需要（第三、四段），而不是比较新旧价值观哪个更好，排除A项；B项只是在文章第二段有所涉及，排除；D项在文章第三、四段提到的目的是说明新国民价值观的需要，而不是单纯讨论合作和竞争，排除。
第2题：
The author gave an example in the third paragraph in order to( ).
A. emphasize the need to place a stronger value on national cooperation
B. explain why the American idea has been based on individual freedom
C. illustrate the fact that the Americans will not sacrifice their personal interest for the good of the entire country
D. support the idea that Americans need the spirit of national cooperation to achieve important national objectives in the 21st century
C[解析lA项中的“national cooperation”在例子中没有体现，例子体现的是个人利益与国家利益的冲突；B项整篇文章都没有解释为什么美国价值观基于个人自由；D项“实现1世纪的目标”文中没有提及。
第3题：
双液压失效下列叙述正确的是()
A、AP和FD不可用但A/THR仍然工作
B、AP、FD、A/THR都不可用
C、AP不再可用但是FD和A/THR仍然工作
第4题：
American government forbade Huawei and ZTE to invest in USA，because it thought( )
B.they came for oil，agricultural land and other resources
C.many deals were politicized and some were corrupt
D.they might hurt American national security
第5题：
A marine chemist issues gas free certificates and is certified by which organization?
A.Mine Safety Appliance Association
B.American Chemical Society
C.Marine Chemists Association
D.National Fire Protection Association
第6题：
What is the basis for the American notion of national good? ( )
A. Individual freedom.
B. Personal property.
C. National cooperation.
D. Both A and B.
A [解析]根据第三段中的“The American idea of the national gooa has never been based on national cooperation but rather on the freedom of the individual…”可知，A项说法符合文意。
第7题：
Which of the following is NOT true according to the last paragraph?（ ）
[A] America will conduct an international-wide aid.
[B] The national-wide financial aid is proved helpful.
[C] Obama doesn't think highly of American aid system.
[D] Mr. Sumner's research is proved of great value.
根据文章最后一段，下列哪一项是不正确的?
[A]美国将在全球范围内实施救助。
[B]国家范围的救助被证明是有效的。
[C]奥巴马对美国救助体系评价不高。
[D]萨姆纳先生的研究具有很高价值。
答案解析：[A]事实细节题。文章最后一段提出，根据萨姆纳先生的研究成果，世界银行的国家分类不具有合理性，因此应该进行改革，奥巴马总统也对美国救助计划不满，所以可以判断[C]、[D]正确；与此同时，奥巴马也提出要将“国际救助”转化为“国家救助”，巴西就是一个成功案例，这样可以更好地在国家范围内进行资金分配，因此可以判断[A]与原文不符，[B]表述正确。 所以[A]为本题答案。
第8题：
The origins(起源) of baseball probably stretch back to 1839 when Abner Doubleday, a civil engineering student, laid out a diamond-shaped field at Cooperstown, New York, and attempted to standardize(使标准化) the rules governing the playing of such games as town ball and four old cat, the ancestors(祖先) of baseball. By the end of the Civil War, interest in the game had grown rapidly. Over 200 teams or clubs existed, some of which toured the country playing rivals; they belonged to a national association of "Baseball Players" that had proclaimed(宣布) a set of standard rules. These teams were amateurs(业余爱好者) or semi-professionals, but as the game waxed in popularity, it offered opportunities for profit, and the first professional team, the Cincinnati Red Stockings, appeared in 1869. Other cities soon fielded professional teams, and in 1876 the present National League was organized chiefly by Albert Spalding. Soon a rival league appeared, the American Association. Competition between the two was intense, and in 1883 they played a post-season(季后赛) contest, the first "world's series". The American Association eventually collapsed, but in 1900 the American League was organized.
1. According to the passage, baseball originated in 1839 because ____.
A、Abner Doubleday invented a special diamond-shaped pitch
B、the rules of earlier games were amalgamated(合并) and regularized
C、civil engineering students became interested in playing games
D、the old games died out and a new one was needed
2. What was different about "Baseball Players" compared with earlier players?
A、They travelled widely.
B、They belonged to many clubs.
C、They played by agreed rules.
D、They were not professional.
3. According to the passage, the Cincinnati Red Stockings were formed in 1869 ____.
A、because baseball had become more popular by then
B、to enable the amateur players to become professional
C、so that the public had the opportunity to profit from a professional team
D、to produce a means of making money
4. From the passage, we understand that the National League was formed in 1876 to ____.
A、reorganize the professional teams
B、enable more professional teams to be set up
C、to provide a governing authority for baseball
D、authorize amateur and professional teams to combine
5. According to the passage, at the turn of the century the only remaining baseball organizations were ____.
A、the American League and the National League
B、the American League
C、the American Association and the American League
D、the American Association
参考答案：1-5：BCDCA
第9题：
Which agency issues a certificate of loading that is evidence that the rules and regulations concerning bulk grain cargoes have been observed ________．
A.American Bureau of Shipping
B.Department of Agriculture
C.National Cargo Bureau
D.Public Health Service
第10题：
B.Ser激酶
C.Tyr激酶
D.Ser和Thr激酶
E.Sel、Thr和Tyr激酶