- 能量的守恒与耗散
- 共3716题
家用电热灭蚊器中电热部分的主要元件是PTC,PTC元件是由钛酸钡等半导体材料制成的用电器,其电阻率与温度的关系如图所示,由于这种特性,因此,PTC元件具有发热、控温双重功能.对此,下列判断中正确的是( )
正确答案
如图所示,由导热材料制成的气缸和活塞将一定质量的理想气体封闭在气缸内,活塞与气缸壁之间无摩擦,活塞上方存有少量液体.将一细管插入液体,由于虹吸现象,活塞上方液体逐渐流出.在此过程中,大气压强与外界的温度保持不变.关于这一过程.下列说法正确的是( )
正确答案
如图所示,固定导热气缸开口向下,内有理想气体,缸内活塞可以自由滑动且不漏气,活塞下挂一个砂桶,桶内装满砂子时,活塞恰好静止,气缸外部环境温度保持不变.现在把砂桶底部钻一个小洞,细砂缓慢流出,则( )
正确答案
固定的气缸内由活塞封闭着一定量的理想气体,活塞在拉力F作用下缓慢地向右移动,如图所示.假设气缸壁和活塞都是不导热的材料,在拉动活塞的过程中,则下列说法正确的是( )
正确答案
Asia’s real boat-rocker is a growing China, not Japan, a senior American economist observed.
There is so much noise surrounding and emanating from the world’s miracle economy that it is becoming cacophonous. In Washington, D. C., the latest idea is that China is becoming too successful, perhaps even dangerously so: while Capitol Hill resounds with complaints of trade surpluses and currency manipulation, the Pentagon and sundry think-tanks echo to a new drumbeat of analysts worrying about China’s 12.6% annual rise in military spending and about whether it might soon have the ability to take preemptive military action to force Taiwan to rejoin it. So it may be no coincidence that for
three consecutive weekends the streets of big Chinese cities have been filled with the sounds of demonstrators marching and rocks being thrown, all seeking to send a different message: that Japan is the problem in Asia, not China, because of its wanton failure to face up to its history; and that by cosying up to Japan in security matters, America is allying with Asia’s pariah.
Deafness is not the only risk from all this noise. The pressure towards protectionism in Washington is strong, and could put in further danger not only trade with China but also the wider climate for trade liberalisation in the Doha round of the World Trade Organisation (WTO). So far words have been the main weapons used between China and Japan, but there is a chance that nationalism in either or both countries could lead the governments to strike confrontational poses over their territorial disputes in the seas that divide them, even involving their navies. And the more that nationalist positions become entrenched in both countries but especially China, the more that street protests could become stirred up, perhaps towards more violence.
All these issues are complex ones and, as is often the case in trade and in historical disputes, finding solutions is likely to be far from simple. A revaluation of the yuan, as demanded in Congress, would not rebalance trade between America and China, though it might help a little, in due course. A "sincere" apology by Japan for its wartime atrocities might also help a little, but it would not suddenly turn Asia’s natural great-power rivals into bosom buddies. For behind all the noise lies one big fact: that it is the rise of China, not the status or conduct of Japan, that poses Asia’s thorniest questions.The "the world's miracle economy" in the beginning of the second paragraph refers to()
A.Asia's real boat-rocker.
B.China's economic success.
C.Japan's economic success.
D.both China and Japan's economic success.
正确答案
B
解析
推理题。文章一开始就谈到,亚洲真正掌舵的是中国,而不是日本;第二段第二句也提到“…中国正变得太成功”,由此可推知第二段开头的“世界的奇迹经济”指的就是中国的经济成功,所以[B]项正确。[A]“亚洲真正的掌舵者”,[C]“日本的经济成功”和[D]“中国和日本的经济成功”都不是文章所要表达的内容。
如图所示,导热的气缸开口向下,缸内活塞封闭了一定质量的理想气体,活塞可自由滑动且不漏气,活塞下挂一个砂桶,砂桶装满砂子时,活塞恰好静止,现将砂桶底部钻一个小洞,让细砂慢慢漏出.气缸外部温度恒定不变,则( )
正确答案
Every spring migrating salmon return to British Columbia’s rivers to spawn. And every spring new reports detail fresh disasters that befall them. This year is no different. The fisheries committee of Canada’s House of Commons and a former chief justice of British Columbia, Bryan Williams, have just examined separately why 1.3 million sockeye salmon mysteriously "disappeared" from the famed Fraser river fishery in 2004.Their conclusions point to a politically explosive conflict between the survival of salmon and the rights of First Nations, as Canadians call Indians.
In 2004, only about 524, 000 salmon are thought to have returned to the spawning grounds, barely more than a quarter the number who made it four years earlier. High water temperatures may have killed many. The House of Commons also lambasted the federal Department of Fisheries and Oceans (DFO) for poor scientific data, and for failing to enforce catch levels. Four similar reports since 1992 have called for the department’s reform. In vain: its senior officials are "in denial" about its ’failings, said the committee.
Mr. Williams’ report added a more shocking twist. He concluded that illegal fishing on the Fraser river is "rampant and out of control", with "no go" zones where fisheries officers are told not to confront Indian poachers for fear of violence. The judge complained that the DFO withheld a report by one of its investigators which detailed extensive poaching and sale of salmon by members of the Cheam First Nation, some of whom were armed.
Some First Nations claim an unrestricted right to fish and sell their catch. Canada’s constitution acknowledges the aboriginal right to fish for food and for social and ceremonial needs, but not a general commercial right. On the Fraser, however, the DFO has granted Indians a special commercial fishery. To some Indians, even that is not enough.
Both reports called for more funds for the DFO, to improve data collection and enforcement. They also recommended returning to a single legal regime for commercial fishing applying to all Canadians.
On April 14th, Geoff Regan, the federal fisheries minister, responded to two previous reports from a year ago. One, from a First Nations group, suggested giving natives a rising share of the catch. The other proposed a new quota system for fishing licences, and the conclusion of long-standing talks on treaties, including fishing rights, with First Nations. Mr. Regan said his department would spend this year consulting "stakeholders" (natives, commercial and sport fishermen). It will also launch pilot projects aimed at improving conservation, enforcement and First Nations’ access to fisheries.Which of the following is NOT the reason for the decrease of salmon according to Mr. Williams()
A.High water temperatures.
B.Shocking twist.
C.Illegal fishing.
D.Officials' failings.
正确答案
B
解析
细节题。文章第二、三段提到水温高、非法捕鱼和官员执法不力都是鲑鱼数量减少的原因,即题目中的[A]、[C]、[D]三项。只有[B]“骇人听闻的歪曲”不是文中提到的原因之一。
根据《中华人民共和国民事诉讼法》的规定,下列关于公示催告程序的表述中,正确的是( )。
A.公示催告期间最短不得少于90日
B.在公示催告期间,转让票据权利的行为无效
C.公示催告案件由票据持有人所在地的基层人民法院管辖
D.公示催告申请人申请人民法院作出除权判决的,应自申报权利期间届满的次日起1年内提出
正确答案
B
解析
公示催告期间最短不得少于60日。公示催告案件由票据支付地的基层人民法院管辖。除权判决自公告之日起生效,当事人不得提起上诉。只有选项B正确。
如图所示,A,B两点表示一定质量的某种理想气体的两个状态,当气体从状态A变化到状态B时( )
正确答案
Many theories have been ______ as to why some women suffer from depression.
A.referred to
B.put forward
C.rest assured
D.left out
正确答案
B
解析
(put forward提出)。句意为:就一些女人为什么患抑郁症而言,已经提出许多理论。A.refer to谈到,提及,查阅;C.rest assured放心;D.leave out省略,遗漏。
如图所示,带有活塞的气缸中封闭一定质量的理想气体,将一个半导体NTC热敏电阻R置于气缺中,热敏电阻与容器外的电源E和电流表组成闭合回路,气缸和活塞具有良好的绝热(与外界无热交换)性能.若发现电流表的读数增大时,以下判断正确的是( )
正确答案
如图5-2-9所示的容器中,A.B各有一个可自由移动的轻活塞,活塞下是水,上为空气,大气压恒定,A.B底部由带有阀门K的管道相连,整个装置与外界绝热.开始A中水面比B中高,打开阀门,使A中的水逐渐流向B中,最后达到平衡,在这个过程中…()
图5-2-9
正确答案
化湿药入汤剂应( )
A.不宜久煎
B.另煎
C.后下
D.先煎
正确答案
A
解析
暂无解析
十二正经中,既分布于目内眦,又分布于目外眦的经脉是( )
A.手少阳三焦经
B.手太阳小肠经
C.足少阳胆经
D.手阳明大肠经
正确答案
B
解析
暂无解析
角法最早记载于( )
A.《五十二病方》
B.《灵枢经》
C.《针灸甲已经》
D.《针灸大成》
正确答案
A
解析
暂无解析
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