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.
突破雅思阅读考试的 关键
胡敏:给“蜗居”“蚁族” 一代的箴言
解除新托福阅读中的 “绊马索”
边玩边学、提高雅思阅读能力 (上)
名师指导 : 雅思阅读部分最基本复习思路
雅思“剑桥系列”阅读题
雅思阅读:浅析同义转换在中的重要性
雅思阅读怎样对付文中的生词 的问题
雅思阅读多项选择题变化 多端
给低龄烤鸭 的雅思阅读 攻略
雅思阅读长难句
雅思阅读考试真题词汇收集——摩斯电码
名师浅谈: 雅思阅读哪一篇更难
雅思阅读泛读中雅思词汇的 心有灵犀
四大绝招助考生稳拿雅思阅读 高分
雅思阅读Summary (Part 3 )
雅思阅读 Summary (Part 2 )
雅思阅读疑难杂症 巧应对
雅思阅读技巧 利用构词法猜测词义
揭秘:《 阿凡达》 纳美人外星语言诞生之谜
雅思阅读:Choices题型攻略小总结
雅思阅读策略:攻心为上 逐个击破
雅思阅读真题类似文章 :蚂蚁智力
如何有效提高雅思阅读答题质量和速度
雅思阅读关键 :掌握英语同义词
实例讲解雅思阅读单选题如何 做对
雅思阅读题型归纳:Summary (Part 4)
雅思阅读:Summary(摘要填空)题的终极技巧
雅思阅读:趋势分析及备考方法
雅思 阅读标题配对 题思路
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