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1、制冷空调专业英语,Unit Two,Lesson 5 Fluid Lesson 6 Level Measurement Lesson 7 Measuring Rate of Fluid Flow Lesson 8 What Is Humidity,New Words & Expressions: Text Notes to the Text Exercise,Lesson 8 What Is Humidity,New Words & Expressions,Lesson 8,咽喉, 喉咙, 嗓音,humidity n.,湿气, 潮湿, 湿度,absolute humidity,绝对湿度,amb
2、ient humidity,环境湿度,atmospheric humidity,大气湿度,constant temperature and humidity,恒温恒湿,percentage humidity,湿度百分数,relative humidity,相对湿度,saturated adj.,渗透的, 饱和的, 深颜色的,barometric adj.,大气压力的,density n.,密度,throat n.,Lesson 8,New Words & Expressions:,坚固的, 充实的,nasal adj.,鼻的, 鼻音的, 护鼻的,bronchial adj.,支气管的,aggr
3、avation n.,加重，更恶化, 恼怒,itchy adj.,使人发痒的,cracking n.,破裂, 裂化,drapery n.,织物, 帏帐, 布料,upholster vt,装饰, 装潢,annoy vt.,使苦恼, 骚扰,static adj.,静态的, 静力的，静电噪声,static electricity,静电,substantial adj.,Text,Humidity is the water vapor within a given space. Absolute humidity is the weight of water vapor per unit volume
4、. Percentage humidity is the ratio of the weight of water vapor per pound of dry air to the weight of water vapor per pound of dry air saturated at the same temperature. .,湿度是特定空间内所含水蒸气的质量。绝对湿度是单位体积内水蒸气的质量。湿度百分数是每磅干空气所含水蒸气的质量与同温度下每磅饱和干空气所含水蒸气的质量比值。,Lesson 8,Text:,Relative humidity is the ratio of th
5、e mol fraction of water vapor present in the air to the mol fraction of water vapor present in saturated air at the same temperature and barometric pressure1. Approximately, it equals the ratio of the partial pressure or density of the water vapor in the air to the saturation pressure or density, re
6、spectively, of the water vapor at the same temperature.,Lesson 8,相对湿度是空气中实际所包含水蒸气的摩尔分数与同温同压下饱和空气所含水蒸气的摩尔分数的比值。它近似于空气水蒸气部分压力或密度分别与同温下水蒸气的饱和压力或密度的比值。,Text:,Although there is a difference between percentage humidity and relative humidity, it is only very slight and is practically negligible at normal r
7、oom temperatures. So, for our purposes, we can say that relative humidity indicates the amount of water vapor actually in the air expressed as a percentage of the maximum amount that the air could hold under the same conditions。,Lesson 8,尽管湿度百分数与相对湿度有所差别，但在通常的室温下差别很小，实际上忽略不计。对实际应用来说，相对湿度就是空气中实际所含水蒸气
8、量和同条件下最大可能包含的水蒸气量的比值。,Text:,The amount of moisture in the air has a direct bearing on personal comfort or discomfort.2 Just as extremely high relative humidity in the summer gives one a soggy feeling, low humidity in the winter in heated homes gives one a dried-out feeling.,Lesson 8,空气中的湿气量与人体舒适度有直接
9、关系。就像夏天极高的湿度给人一种沉闷的感觉；冬天暖室中低湿度给人一种干燥的感觉。,Text:,When cold air enters the house during the winter, it is heated; thus its moisture holding capacity is increased. If moisture is not added to this air, indoor relative humidity drops below the minimum range for personal comfort.,Lesson 8,冬天冷空气进入室内，温度升高；因
10、此空气的含湿能力提高，如果不给空气加湿，相对湿度下降至人体舒适感的最小范围之下。,Text:,In most homes without humidification equipment, heated indoor air is much too dry for the well being of its occupants, their pets, plants, and furnishings. Proper humidity control is simple with a humidifier. Simply dial the desired humidity on the humi
11、distat.,Lesson 8,在没有加湿设备的大多数家庭内，对居住者、宠物、植物、家具来说，被加热的室内空气太干燥了。用加湿器很容易达到湿度控制，只要在恒湿器上调动到想要的湿度。,Text:,Properly humidified air enhances personal comfort and well being by helping to prevent throat irritations3, nasal discomfort, bronchial aggravations, and itchy dry skin caused by hot, dry indoor air. Fl
12、oors, doors, frames, and wood furniture will have a minimum of drying out, cracking, or warping.,Lesson 8,适当加湿的空气有利于预防热的、干燥的室内空气导致的咽喉痛、鼻子不适、支气管恶化和干性皮肤骚痒等症状；地面、门、框架和木质家具发生干裂、变形的可能会降到最小。,Text:,Draperies and upholstering stay fresh and wear longer. Annoying minor shocks caused by static electricity are
13、 greatly reduced. House plants stay fresher and prettier. A home can be kept more comfortable at lower temperatures with properly humidified air. This helps lower heating costs.,Lesson 8,布料和室内装潢会更清洁耐用。被静 电干扰导致的恼人的微小震动会大大缩减。室内植物也会更清新可人。处在适当加湿 的低温空气中会更舒适。这有利于降低加 热成本。,Text:,As stated before, the warmer
14、 the air, the more moisture it can hold. Air in a home heated to 70F can hold about 8 grains of moisture per ft3.4 that is 100%relative humidity. If there are only 2 grains/ft3 in the home, this is one quarter of the capacity of the air to hold moisture. Therefore, the relative humidity is also one
15、quarter or 25%. The air can hold four times as much water.,Lesson 8,按规定，气温越高，含湿能力越大。室温达到70华氏温度，每立方英尺空气中湿量可达8格令。这时相对湿度为100%。如果每立方英尺空气中湿量仅为2格令，这是空气含湿能力的四分之一。因此，相对湿度为四分之一或25%。实际上空气的含湿量可达四倍之多。,Text:,Because of this capability of warm air to hold more water than cold air, a substantial reduction of relat
16、ive humidity is taking place in every unhumidified or underhumidified home where winter heating is prevalent.,Lesson 8,因为暖空气的含湿量比冷空气多，冬天使用加热装置，而没有加湿或加湿不够的房间内，空气的相对湿度一定会下降。,Notes to the Text,Lesson 8,Notes to the Text,1.Relative humidity is the ratio of the mol fraction of water vapor present in the air to the mol fraction of water vapor present in saturated air at the same temperature and barometric pressure.,Lesson 8,句中的“saturated air” 应译为“饱和空气” 。 例如： saturated solution 饱和溶液 saturated rock
