某混凝土设备基础：长×宽×厚＝15m×4m×3m，要求整体连续浇筑，拟采取水平分层浇筑方案。现有三台搅拌机，每台生产率为6m3／h，若混凝土的初凝时间为3h，运输时间为0.5h，每层浇筑厚度为50cm，试分析此方案是否可行.

>> 高等继续教育 / 土木工程施工

高等继续教育 / 土木工程施工

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土木工程施工

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20[多选题] 井下采用矿车运输时，可以采用的调车方法有 A.固定错车场调车 B.活动错车场调车 C.浮放道岔调车 D.翻框式调车器调车 E. 胶带转载机转载河南理工大学

小女孩甲（8岁）与小男孩乙（12岁）放学后常结伴回家。一日，甲对乙讲：“听说我们回家途中的王家昨日买了一条狗，我们能否绕道回家？”乙答：“不要怕！被狗咬了我负责。”后甲和乙路经王家同时被狗咬伤住院。该案赔偿责任应如何承担？侵权行为法学

6、正等测轴侧图的轴向缩短系数正确的是( )。 A. 1.2 B. 1 C. 0.82 D. 0.5土木工程CAD

市场型推销阶段推销活动的特点是现代推销技术

3. 某反应的活化能是33kJ·mol-1，当T = 300 K时，温度增加1K，反应速率常数增加的百分数约为 A、0.045 B、0.094 C、0.11 D、0.5中石油

7、 There seems never to have been a civilization without toys, but when and how they developed is unknown. They probably came about just to give children something to do. In the ancient world, as is today, most boys played with some kinds of toys and most girls with another. In societies where social roles are rigidly determined, boys pattern their play after the activities of their fathers and girls after the tasks of their mothers. This is true because boys and girls are being prepared, even in play, to step into the roles and responsibilities of the adult world. What is remarkable about the history of toys is not so much how they changed over the centuries but how much they have remained are same. The changes have been mostly in terms of craftsmanship, mechanics, and technology. It is the universality of toys with regard to their development in all parts of the world and their persistence to the present that is amazing. In Egypt, the Americas, China, Japan and among the Arctic (北极的)peoples, generally the same kinds of toys appeared. Variations depended on local customs and ways of life because toys imitate their surroundings. Nearly every civilization had dolls, little weapons, toy soldiers, tiny animals and vehicles. Because toys can be generally regarded as a kind of art form, they have not been subject to technological leaps that characterize inventions for adult use. The progress from the wheel to the oxcart to the automobile is a direct line of ascent (进步). The progress from a rattle (拨浪鼓)used by a baby in 3000 BC to one used by an infant today, however, is not characterized by inventiveness. Each rattle is the product of the artistic tastes of the times and subject to the limitations of available materials. 1.The reason why the toys most boys play with are different from those that girls play with is that _ _ _ _ _ _ _ _ .A) their social roles are rigidly determinedB) most boys would like to follow their fathers‘professionsC) boys like to play with their fathers while girls with their mothersD) they like challenging activities 2.One aspect of “the universality of toys”lies in the fact that _ _ _ _ _ _ _ _ .A) technological advances have greatly improved the durability of toysB) the improvement of craftsmanship in making toys depends on the efforts of universitiesC) the exploration of the universe had led to the creation of new kinds of toysD) the basic characteristics of toys are the same the world over3.Which of the following is the author‘s view on the historical development of toys?A) The craftsmanship in toy-making has remained essentially unchanged.B) Toys have remained basically the same all through the centuries.C) The toy industry has witnessed great leaps in technology in recent years.D) Toys are playing an increasingly important role in shaping a child‘s character. 4.Regarded as a kind of art form, toys _ _ _ _ _ _ _ _ .A) follow a direct line of ascentB) also appeal greatly to adultsC) are not characterized by technological progress D) reflect the pace of social progress5.The author uses the example of rattle to show that _ _ _ _ _ _ _ _ . A) in toy-making there is a continuity in the sue of materialsB) even the simplest toys can reflect the progress of technologyC) even the simplest toys can reflect the progress of technologyD) even a simple toy can mirror the artistic tastes of the time 大学英语2