问题 单项选择题

用雷氏夹法测水泥的安定性,沸煮时指针朝向正确的是______。

A.朝下
B.水平悬空
C.朝上
D.以夹子能稳定放置为准

答案

参考答案:C

解析: 参考JTG E30—2005试验规程中T 0505—2005水泥标准稠度用水量、凝结时间、安定性检验方法相关技术规定及试验操作方法。雷氏夹法:①按标准稠度用水量确定的方法和结果拌和水泥净浆。②将事先校准的雷氏夹放在涂有一薄层黄油玻璃板上,把制备好的标准稠度水泥净浆装填在雷氏夹的试模里,并用小抹刀插捣多次,确保密实,然后抹平。每个水泥样品至少制备两个试样,再盖上一块涂油的玻璃板,放入养护箱中养护24h±2h。③沸煮试验前,首先调整好箱内水位,要求在整个沸煮过程中箱里的水始终能够没过试件,不可中途补水,同时要保证水在30min±5min内开始沸腾。④从养护箱中取出雷氏夹,去掉玻璃板,先测量雷氏夹指针尖端的距离A,精确到0.5mm,随后将试件放入沸煮箱水中的试架上,要求指针朝上,然后开始加热,试箱中的水在30min内沸腾,并恒沸180min±5min。⑤沸煮结束后,立即放掉箱中的热水,打开箱盖,待冷却至室温,取出试件。测定雷氏夹指针尖端的距离C,当两个雷氏夹试件煮后指针尖端增加的距离C—A的平均值不大于5.0mm时,则认为该水泥安定性合格。

单项选择题 A3/A4型题
单项选择题

Should anyone much care whether an American boy living overseas gets six vicious thwacks on his backside So much has been argued, rejoined and rehashed about the case of Michael Fay, an 18-year-old convicted of vandalism and sentenced to a caning in Singapore, that an otherwise sorry little episode has shaded into a certified International Incident, complete with intercessions by the U. S. head of state. An affair has outraged American libertarians even as it has animated a general debate about morality East and West and the proper functioning of U.S. law and order.

Which, to all appearances, is what Singapore wanted. The question of whether anyone should care about Michael Fay is idle. though Singapore officials profess shock at the attention his case had drawn, they know Americans care deeply about the many sides of this issue. Does a teenager convicted of spraying cars with easily removable paint deserve half a dozen powerful strokes At what point does swift, sure punishment become torture By what moral authority can America, with its high rates of lawlessness and license, preach of a safe society about human rights

The caning sentence has concentrated minds wondrously on an already lively domestic debate over what constitutes a due balance between individual and majority rights. Too bad Michael Fay has become a focus for this discussion. Not only does he seem destined to be pummeled and immobilized, but the use of Singapore as a standard for judging any other society, let alone the cacophonous U. S. , is fairly worthless.

To begin with, Singapore is an offshore republic that tightly limits immigration. Imagine crime-ridden Los Angeles, to which Singapore is sometimes contrasted, with hardly any inflow of the hard-luck, often desperate fortune seekers who flock to big cities. Even without its government’s disciplinary measures, Singapore more than plausibly would be much the same as it is now. An academic commonplace today is that the major factor determining social peace and prosperity is culture--a sense of common identity, tradition and values.

Unlike Singapore, though, the U. S. today is a nation in search of a common culture, trying to be a universal society that assimilates the traditions of people from all over the world. Efforts to safeguard minority as well as individual rights have produced a gridlock in the justice system. Its troubles stem more from the decay of family life than from any government failures. Few societies can afford to look on complacently. As travel eases and cultures intermix, the American experience is becoming the world’s.

The circumstances of this affair--evidently no Singaporean has ever been punished under the Vandalism Act for defacing private property--suggest that Singapore has used Fay as an unwilling point man in a growing quarrel between East and West about human rights.

The reaction of the U.S. to the case of Michael Fay could best be described as()

A. big surprise

B. grave outrage

C. great concern

D. heavy agony