13 Skyscrapers and Environment
In the late 1960s, many people in North America turned their attention to environmental problems, and new steel-and-glass skyscrapers were widely criticized. Ecologists pointed out that a cluster of tall buildings in a city often overburdens public transportation and parking lot capacities.
Skyscrapers are also lavish consumers, and wasters, of electric power. In one recent year, the addition of 17 million square feet of skyscraper office space in New York City raised the peak daily demand for electricity by 120, 000 kilowatts-enough to supply the entire city of Albany, New York, for a day.
Glass-walled skyscrapers can be especially wasteful. The heat loss through a wall of half-inch plate glass is more than ten times that through a typical masonry wall filled with insulation board. To lessen the strain on heating and air-conditioning equipment, builders of skyscrapers have begun to use double-glazed panels of glass, and reflective glasses coated with silver or gold mirror films that reduce glare as well as heat gain. However, mirror-walled skyscrapers raise the temperature of the surrounding air and affect neighboring buildings.
Skyscrapers put a severe strain on a citys sanitation facilities, too. If fully occupied, the two World Trade Center towers in New York City would alone generate 2.25 million gallons of raw sewage each year-as much as a city the size of Stanford, Connecticut , which has a population of more than 109, 000.
09年中考英语总复习经典习题讲解3一冠词
常用英语词语辨析105组(11)
常用英语词语辨析105组(3)
初中英语常用词组1 动词词组
常用英语词语辨析105组(4)
张惠妹《排山倒海》英文版
2010年中考英语词汇熟词新义:start
09年中考英语总复习经典习题讲解4一数词
初中英语常用词组3 量词词组
2009中考英语词汇表 系列M
词汇笔记 五种词汇的学习方法 超强
初中英语常用词组复习2
09年中考英语总复习经典习题讲解1一冠词
高中英语词汇:80后“A到Z”生存法则
中考英语词汇“for短语”全攻略
2009中考英语词汇短语集锦 (1)
09年英语短语集中联想记忆110条
初中英语常用词组复习1
2010年中考英语词汇旧词新义:blind
2009中考英语词汇表 系列R
2010年中考英语词汇旧词新义:clean
2009中考英语词汇表 系列O
2009中考英语词汇表 系列T
初中英语常用词组2 介词短语词组
09年中考英语总复习经典习题讲解2一名词
常用英语词语辨析105组(2)
十个窍门积累英语词汇
2009最新中考英语单项填空模拟考试卷 附详解答案
英乐时空Here I Am
初中英语 词缀记忆法
| 不限 |
| 英语教案 |
| 英语课件 |
| 英语试题 |
| 不限 |
| 不限 |
| 上册 |
| 下册 |
| 不限 |