绦虫病发病年龄以（）多见。（） A.青壮年 B.10岁以下儿童 C.60岁以上老人

超高温灭菌方法有两种主要的超高温处理方法：它们是（）和间接加热法。

During the years after the terrorist attack on the World Trade Center, structural engineers have been trying hard to solve a question that would otherwise have been completely unthinkable: Can building be designed to stand catastrophic blasts (攻击；爆破) by terrorists?

Soon after the terrorist attacks on the twin towers, structural engineers from the University at Buffalo and the Multidisciplinary Center for Earthquake Engineering Research (MCEER) traveled to ground zero as part of a project funded by the National Science Foundation. They spent two days beginning the task of formulating (构思) ideas about how to design such structures and to search for clues on how to do so in buildings that were damaged, but still are standing.

“Our objective in visiting ground zero was to go and look at the buildings surrounding the World Trade Center, those buildings that are still standing, but that sustained damage,” said Mr. Bruneau, Ph.D. “Our immediate hope is that we can develop a better understanding as to why those buildings remain standing, while our long-term goal is to see whether earthquake engineering technologies can be married to existing technologies to achieve enhanced performance of buildings in the event of terrorist attacks,” he added.

Photographs taken by the investigators demonstrate the monumental damage to the World Trade Center towers and buildings nearby. One building a block away from the towers remains standing, but was badly damaged. “This building is many meters away from the World Trade Center and yet we see a column (柱子) there that used to be part of that building,” explained A. Whittaker, Ph.D. “The column became a missile that shot across the road, through the window and through the floor.”

The visit to the area also brought some surprises, according to the engineers. For example, the floor framing (框架) system in one of the buildings was quite strong , allowing floors that were pierced by tons of falling debris (残砾) to survive. “Good framing systems may provide a simple, but reliable strategy for blast resistance,” he added. Other strategies may include providing alternate paths for gravity loads in the event that a load-bearing column fails. “We also need a better understanding of the mechanism of collapse,” said A. Whittaker. “We need to find out what causes a building to collapse and how you can predict it.”

A. Reinhorn, Ph.D. noted that “earthquake shaking has led to the collapse of buildings in the past. Solutions developed for earthquake-resistant design may apply to blast engineering and terrorist-resistant design. Part of our mission now is to transfer these solutions and to develop new ones where none exist at present.”

小题1:The question raised in the first paragraph is one _____ .

A．that was asked by structural engineers a month ago

B．that is too difficult for structural engineers a month ago

C．that was never thought of before the terrorist attack

D．that terrorists are eager to find a solution to小题2:The column mentioned by Dr. Whittaker _____ .

A．was part of the building close to the World Trade Center

B．was part of the World Trade Center

C．was shot through the window and the floor of the World Trade Center

D．damaged many buildings near the World Trade Center小题3:A surprising discovery made by the investigators during their visit to ground zero is that _____.

A．floors in the faraway buildings remained undamaged

B．some floor framing systems demonstrate resistance to explosion

C．complex floor framing systems are more blast resistant

D．floors in one of the buildings were pierced by tons of debris小题4: What Dr. Reinhorn said in the last paragraph may imply all the following EXCEPT that _____.

A．blast engineers should develop new solutions for terror-resistant design

B．blast engineering can borrow technologies developed for terror-resistant design

C．solutions developed for earthquake-resistant design may apply to terrorist-resistant design

D．blast engineering emerges as a totally new branch of science

1971年，毛 * * 在得知中国运动员庄则栋和美国运动员科恩在日本友好接触的情况后说“现在正是千载难逢的好时机”，并请周恩来指示有关部门立即邀请美国乒乓球队访华。从中国的外部环境角度来看，中国政府积极改善中美关系的主要原因是(　　)

A．美国尼克松政府放弃了遏制中国的政策

B．中国的国防安全面临巨大的外部压力

C．中国政府“不结盟”外交原则的必然要求

D．解决台湾问题，实现祖国统一大业的需要

简述检查前轮偏转角的必要性。

在空调制冷系统中，高压开关的作用是（）

A、控制风扇高速旋转、加速冷却冷凝器

B、控制制冷管路压力升高，自动断开压缩机电磁离合器电路

C、以上两种作用都有

D、控制制冷管路的最低压力、自动断开压缩机电磁离合器电路