某公共建筑的集中热水采暖的二次水系统,总热负荷为3200kW,供回水温度为95/70

题型:单项选择题

问题:

某公共建筑的集中热水采暖的二次水系统,总热负荷为3200kW,供回水温度为95/70℃,室外主干线总长1600m,如果选用联轴器连接的循环水泵时,水泵的设计工况点的轴功率计算值应是下列哪一项(取整数)

A.19kW
B.17kW
C.15kW
D.13kW

考点:注册公用设备工程师暖通空调专业案例暖通空调专业案例
题型:单项选择题

如图,已知OC平分∠AOB,P是OC上一点,PD⊥OA于D,PE⊥OB于E.如果PD=2cm,那么PE=______cm.

题型:单项选择题

税收对经济的调控(  )

①是运用直接调控手段实现的 ②是通过对经济利益的调整实现的 ③可以促进国民经济的持续、快速、健康发展 ④可以弥补市场的缺陷和不足

A.①②③

B.①②④

C.①③④

D.②③④

题型:单项选择题

Seth DeBolt is a plant scientist at the University of Kentucky US. He and other scientists wanted to find a source of fuel that poor people in rural areas of developing countries could use to make electricity.

The United Nations Development Program says a billion and a half people have no electricity. A billion others have an undependable supply.

Professor DeBolt went on a study trip to rural Indonesia. He saw that there was very little waste in the use of agricultural products. Everything that farmers grew was used for something. Even the remains of fruit that people did not eat were fed to chickens.

Little waste meant there was little that could be used for fuel. Growing a separate fuel crop would take land away from food crops. That was something Professor DeBolt did not want to do.

DeBOLT said, "The people at most risk with respect to energy poverty, typically they're the same people who have food insecurity issues as it is. And then any change in availability would be most damaging to that group of people."

But he found one item that was in plentiful supply and would not create competition between food and fuel. Coconut shells are generally thrown out. Yet Professor DeBolt says it has an "excellent" heating value. All someone needs is a way to release that energy.

DeBolt says he and his team see possibilities for coconut power. "Coconuts are growing here and these are the areas where there is possibility for energy poverty to be eased at least in part by these small-scale production systems."

The researchers say these systems could provide as much as thirteen percent of the energy needs of a country like Indonesia. Other tropical countries with large crops of coconuts and similar fruit could benefit, as well.

But DeBolt says this is not a perfect solution. There are technical questions, like how to safely deal with the dangerous waste produced in the process. And there needs to be money to get these projects started.

小题1:Professor DeBolt went on a study trip to rural areas of developing countries to      .

A.help farmers make full use of waste

B.seek certain materials to make electricity

C.persuade farmers to grow more coconuts

D.find a suitable place to carry out the experiment小题2:DeBolt thought it was not a good idea to grow fuel crops because      .

A.there are plenty of coconuts

B.local farmers have no interest in it

C.it would make food problems worse

D.fuel crop has little use for local farmers小题3:The last two paragraphs mainly tell us that coconut power      .

A.needs further experiments and efforts

B.can help solve energy problem perfectly

C.will cause technique and money problems

D.has drawn Indonesia's government attention小题4:What might be the best title for the passage?

A.Make Full Use Of Coconuts

B.Make Power From Coconuts

C.A Perfect Solution

D.Food And Energy Problems

题型:单项选择题

根据现行《火灾自动报警系统设计规范》,消防控制室应设置火灾警报装置与应急广播的控制装置,其控制程序应符合下列哪些要求()

A.含多个防火分区的单层建筑,应先接通着火的防火分区及其相邻的防火分区

B.二层及以上的楼层发生火灾,应先接通着火层及其相邻的上、下层

C.首层发生火灾,应先接通本层、二层及地下各层

D.地下室发生火灾,应先接通地下各层及首层

题型:单项选择题

酒类的主要卫生问题是

A.真菌毒素、多环芳烃、棉酚
B.甲醇、杂醇油、醛类
C.重金属污染
D.微生物、有害化学物质污染
E.亚硝基化合物污染

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