下列说法中正确的是( ) A.蔗糖和麦芽糖不互为同分异构体 B.向鸡蛋清溶液中滴

题型:选择题

问题:

下列说法中正确的是(  )

A.蔗糖和麦芽糖不互为同分异构体

B.向鸡蛋清溶液中滴加少量硫酸铵溶液,会影响蛋白质的活性

C.加酶洗衣粉可用来洗涤棉织品、毛织品、腈纶织品和涤纶织品

D.合成聚乙烯塑料、聚氯乙烯塑料和聚苯乙烯塑料所发生的反应类型相同

考点:蔗糖麦芽糖氨基酸合成有机高分子化合物食品添加剂的使用
题型:选择题

In the span of 18 months, Isaac Newton invented calculus, constructed a theory of optics, explained how gravity works and discovered his laws of motion. As a result, 1665 and the early months of 1666 are termed his annus mirabilis. (46)It was a sustained sprint of intellectual achievement that no one thought could ever be equaled. But in a span of a few years just before 1900, it all began to unravel. One phenomenon after another was discovered which could not be explained by the laws of classical physics. (47) The theories of Newton, and of James Clerk Maxwell who followed him in the mid-19th century by crafting a more comprehensive account of electromagnetism, were in trouble.
Then, in 1905, a young patent clerk named Albert Einstein found the way forward. In five remarkable papers, he showed that atoms are real (it was still controversial at the time), presented his special theory of relativity, and put quantum theory on its feet. It was a different achievement from Newton’s year, but Einstein’s annus mirabilis was no less remarkable. He did not, like Newton, have to invent entirely new forms of mathematics. However, he had to revise notions of space and time fundamentally. (48) And unlike Newton, who did not publish his results for nearly 20 years, so obsessed was he with secrecy and working out the details, Einstein released his papers one after another, as a fusillade of ideas.
For Einstein, it was just a beginning-he would go on to create the general theory of relativity and to pioneer quantum mechanics. While Newton came up with one system for explaining the world, Einstein thus came up with two. Unfortunately, his discoveries- relativity and quantum theory-contradict one another. Both cannot be true everywhere, although both are remarkably accurate in their respective domains of the very large and the very small. Einstein would spend the last years of his life attempting to reconcile the two theories, and failing. (49) But then, no one else has succeeded in fixing the problems either, and Einstein was perhaps the one who saw them most clearly.
When Einstein was awarded a Nobel prize, in 1921, it was for the first of his papers of 1905, which proved the existence of photons-particles of light. (50) Up until that paper, completed on March 17th and published in Annalen der Physik (as were the other 1905 papers), light had been supposed to be a wave, since this explains the interference patterns created when it passes through a grating. Einstein, however, began from a different premise, by considering the so-called "black-body experiment".

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目前Rb的治疗说法错误的是()。

A.为提高患儿生存质量,一般不再主张早期摘除眼球

B.化疗仅作晚期姑息治疗

C.眼球摘除时,视神经切除应大于10mm

D.巩膜表面放射敷贴治疗优于外放射治疗

E.肿瘤大于50%眼球容积并玻璃体播种、视力丧失者,仍应进行眼球摘除术,术后辅助放疗化疗

题型:选择题

以下句子中在语言运用的得体方面有误,请分别指出来,并加以改正(4分)

①这个双休日我将登门拜访你,你可以在家恭候。(        )

②社区里退休老校长对有关家长说:“暑假具有不同专长的大学生将登门为您的令郎、令爱辅导功课。”(           )

③阅览室厉老师:原来约定的我班明天自学课来贵室集体阅读一事,因要单元测验,现决定改期;时间再另行磋商。(               )

④我对李铭说:“你初中时的绘画作品,还惠存在我家,我还常拿出来欣赏。”(           )

题型:选择题

下列哪项不属于超短波安全防护措施内容()

A.减少环境内金属物品就可以减少金属对高频电磁波的反射

B.避免高频电对眼、睾丸部位的大强度辐射。妊娠期间不接受高频电治疗,不在高频电环境中工作

C.治疗操作时不使辐射器空载或对着周围环境中的人员

D.不必要建立屏蔽屏风或屏蔽室

E.密切接触大强度微波者可戴微波防护眼镜或穿微波防护服

题型:选择题

(),唐代诗人,擅长七绝,多写当时边塞军旅生活,气势雄浑,格调高昂,《从军行》七首、《芙蓉楼送辛渐》和《出塞》两首都很有名。

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