-
根据《混凝土用水标准》JGJ63-2006的要求,水质检验水样不应少于()L;用于测定水泥凝结时间和胶砂强度的水样不应少于3L。
-
当蒸汽中含有空气时,空气附在冷却面上影响蒸汽通过,使热阻(),水蒸汽凝结换热显著()。
-
默认保存为页面内容一部分的状态管理方式是
-
单机挂车的数量不分空重及区段内坡度,均以()辆为限,但不准超过该区段牵引定数,并接通制动软管。
-
儿童EBV感染的主要传播途径是()
-
Moderate Earthquake Strikes England A moderate earthquake struck parts of southeast England on 28 April 2007, toppling chimneys from houses and rousing residents from their beds. Several thousand people were left without power in Kent County. One woman suffered minor head and neck injuries. "It felt as if the whole house was being slid across like a fun-fair ride," said the woman. The British Geological Survey said the 4. 3-magnitude quake struck at 8:19 a.m. and was centered under the English Channel, about 8.5 miles south of Dover and near the entrance to the Channel Tunnel. Witnesses said cracks appeared in walls and chimneys collapsed across the county. Residents said the tremor had lasted for about 10 to 15 seconds. "I was lying in bed and it felt as if someone had just got up from bed next to me." said Hendrick van Eck, 27, of Canterbury about 60 miles southeast of London. "I then heard the sound of cracking, and it was getting heavier and heavier. It felt as if someone was at the end of my bed hopping up and down." There are thousands of moderate quakes on this scale around the world each year, but they are rare in Britain. The April 28 quake was the strongest in Britain since 2002 when a 4.8-magnitude quake struck the central England city of Birmingham. The country's strongest earthquake took place in the North Sea in 1931, measuring 6.1 on the Richter scale. British Geological Survey scientist Roger Musson said the quake took place on 28 April in an area that had seen several of the biggest earthquakes ever to strike Britain, including one in 1580 that caused damage in London and was felt in France. Musson predicted that it was only a matter of time before another earthquake struck this part of England. However, people should not be scared too much by this prediction, Musson said, as the modern earthquake warning system of Britain should be able to detect a forthcoming quake and announce it several hours before it takes place. This would allow time for people to evacuate and reduce damage to the minimum. The country′s strongest earthquake took place in London in 1580.()
-
轿厢护脚板垂直部分的高度不小于()米.
-
稳压二极管的正常工作状态是()。
-
在生产中,气开式自力调压阀突然关闭是由下列原因引起的()
-
有人说:“格鲁派教理研究方面功底深,修证成就差;宁玛派教理研究功底差,修证成就高。”这话对吗?