题干

对下列实验指定容器中的水,其解释没有体现水的主要作用的是(  )

A:量筒中的水:通过水体积的变化得出O2体积

B:集气瓶中的水:吸收放出的热量

C:集气瓶中的水:冷却溅落熔融物,防止集气瓶炸裂

D:烧杯中的水:加热铜片;隔绝空气

上一题 下一题 0.0难度 选择题 更新时间:2019-10-10 10:55:07

答案(点此获取答案解析)

B

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    China is fully prepared to export a full supply chain of high-speed railway technology, according to industry experts.

    China Railway Corp, the national rail operator, said exports of railway equipment and railway construction projects are proceeding well, and breakthroughs are being made in a number of projects overseas.

    Among the projects, the first full-chain commission, the Jakarta to Bandung high-speed railway in Indonesia, which includes technology, design, construction, equipment manufacture, supply of resources, operations management and staff training, has been granted a construction permit and work is proceeding smoothly.

    “China's railways have established a comprehensive and advanced technology system, which is able to provide overseas customers with solutions from many different perspectives, including financing, construction, operations, and research and development,” said Yang Zhongmin, the CRC's deputy chief engineer, who added that China's railway system is competitive in terms of technology and economy of use.

    According to Yang, the nation's railway equipment and infrastructure (基础设施) service businesses have entered markets in Asia, Europe, North America and Africa.

    Last year, Joko Widodo, president of Indonesia, and Malaysian Prime Minister Najib Razak, rode Chinese-made bullet trains.

    Yang Hao, a professor of rail transportation management at Beijing Jiaotong University, said China has a major advantage in that it is able to export a full range of railway technology: “For example, it is inconvenient to import the technology for the signaling system from one country and civil engineering technology from another.”