(4分)下图是甲、乙、丙三种固体的溶解度曲线,试回答: (1)t3℃时,甲、乙

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问题:

(4分)下图是甲、乙、丙三种固体的溶解度曲线,试回答:

(1)t3℃时,甲、乙、丙三种物质溶解度的大小关系是        

(2)t3℃时,若将50g的甲、乙两种物质分别加入到100g水中,

充分溶解后,所得的溶液在溶解度曲线图中可表示为   (“A”、“B”或“C”)点,若将甲溶液降温至t1℃,溶液的变化情况是     

I.溶液变为饱和 Ⅱ.溶解度增加 Ⅲ.溶质减少 Ⅳ.溶质的质量分数不变

考点:固体溶解度气体溶解度
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水浴是通过水温和水的机械作用对身体进行刺激达到锻炼的目的,水浴可分为()。

A、冷水浴、我、热水浴

B、冷水浴、温水浴

C、只有冷水浴可称为水浴

D、只能是温水浴

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保险公司要想对险种组合作出决策,首先要对保险商品进行分析,其内容包括( )。①未来主要的保险商品 ②目前主要险种状况 ③可能成为主要盈利来源的险种 ④销路尚未完全失去,仍可继续经营的险种 ⑤已经失去销路或者销路未打开就衰退的险种

A.①②③④⑤

B.①②③④

C.②④⑤

D.②③④

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中央型腰椎间盘突出症和马尾神经瘤最有意义的鉴别点是

A.鞍区麻痹
B.脊髓造影
C.腰穿脑脊液检查
D.肛门括约肌功能检查
E.X线片检查

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以下有关帧中继网的描述中不正确的是 ( ) 。

A. 帧中继在虚电路上可以提供不同的服务质量

B.在帧中继网中,用户的数据速率可以在一定的范围内变化

C.帧中继网只提供永久虚电路服务

D.帧中继不适合对传输延迟敏感的应用

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[A] However, the production of TG is controlled by an enzyme that is, in turn, encoded by a gene called UGT2B17. This gene comes in two varieties, one of which has a part missing and therefore does not work properly. A person may thus have none, one or two working copies of UGT2B17, since he inherits one copy from each parent. Dr Schulze guessed that different numbers of working copies would produce different test results. She therefore gave healthy male volunteers whose genes had been examined a single 360mg shot of testosterone (the standard dose for legitimate medical use) and checked their urine to see whether the shot could be detected.

[B] Dr Schulze also says there is substantial ethnic variation in UGT2B17 genotypes. Two-thirds of Asians have no functional copies of the gene (which means they have a naturally low ratio of TG to EG), compared with under a tenth of Caucasians--something the anti-doping bodies may wish to take into account.

[C] The test usually employed for testosterone abuse relies on measuring the ratio of two chemicals found in the urine, testosterone glucuronide (TG) and epitestosterone glucuronide (EG). The former is produced when testosterone is broken down, while the latter is unrelated to testosterone metabolism, and can thus serve as a reference point for the test. Any ratio above four of the former to one of the latter is, according to official Olympic policy, considered suspicious and leads to more tests.

[D] The result was remarkable. Nearly half of the men who carried no functional copies of UGT2B17 would have gone undetected in the standard doping test. By contrast, 14% of those with two functional copies of the gene were over the detection threshold before they had even received an injection. The researchers estimate this would give a false-positive testing rate of 9% in a random population of young men.

[E] The agencies have had remarkable success. Testing for anabolic steroids (in other words, artificial testosterone) was introduced in the 1970s, and the incidence of cheating seems to have fallen dramatically as a result (see chart). The tests, however, are not foolproof. And a study just published in the Journal of Clinical Endocrinology & Metabolism by Jenny Jakobsson Schulze and her colleagues at the Karolinska Institute in Sweden suggests that an individual’s genetic make-up could confound them in two different ways. One genotype, to use the jargon, may allow athletes who use anabolic steroids to escape detection altogether. Another may actually be convicting the innocent.

[F] Cheating in sport is as old as sport itself. The athletes of ancient Greece used potions to fortify themselves before a contest, and their modern counterparts have everything from anabolic steroids and growth hormones to doses of extra red blood cells with which to invigorate their bodies. These days, however, such stimulants are frowned on, and those athletes must therefore run the gauntlet of organisations such as the World Anti-Doping Agency, which would rather they competed without resorting to them.

[G] In the meantime, Dr Schulze’ s study does seem to offer innocents a way of defending themselves. Athletes travelling to Beijing for the Olympic games later this year may be wise to travel armed not only with courage and the "spirit of Olympianism", but also with a copy of their genetic profile, just in case.

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