Color of water 水的颜色.ppt

1、Color of water 10海技2班 尹珏琛,While relatively small quantities of water appear to be colorless, pure water has a slight blue tint that becomes a deeper blue as the thickness of the observed sample increases. The blue hue of water is an intrinsic property and is caused by selective absorption and scatte

2、ring of white light. Impurities dissolved or suspended in water may give water different colored appearances.,虽然相对少量的水近似无色,但纯水是有一点轻微的蓝色的,当观察的水的厚度增加是，蓝色就会变得深一些。水的蓝色色度是它的一种本征性质,这是由于水选择性吸收和散射白色的光。杂质溶解或悬浮在水中可能使水表现出不同的颜色。,Contents 1 Intrinsic color 固有颜色 2 Color of lakes and oceans 湖泊和海洋的颜色 3 Color of gla

3、ciers 冰川的颜色 4 Color of water samples 水样的颜色 5 Water quality and color 水质和水色 6 Color names 颜色名称 7 References 引用 8 Further reading 延伸阅读 9 External links 外部链接,Intrinsic color For more details on this topic, see Electromagnetic absorption by water. The intrinsic natural color of liquid water may be demon

4、strated by looking at a white light source through a long pipe, filled with purified water, that is closed at both ends with a transparent window. The light turquoise blue color is caused by weak absorption in the red part of the visible spectrum. 关于这个主题的更多细节,请参阅水对电磁的吸收. 水的固有自然颜色可以通过观察白色光源穿过一根充满纯水,两

5、端是透明的窗口密封的长管来展示。浅蓝色是由于对可见光谱中的红色的部分弱吸收造成的.,For most substances, absorptions in the visible spectrum are usually attributed to excitations of electronic energy states. However, water is a simple 3-atom molecule, H2O, and all its electronic absorptions occur in the ultraviolet region of the electromagn

6、etic spectrum and are therefore not responsible for the color of water in the visible region of the spectrum. 对大多数物质,可见光谱的吸收通常归因于电子能量状态的激发。然而,水是一个简单的3个原子分子,它所有的电子吸收（光谱）发生紫外线区域的电磁频谱，因此在可见光区域光谱内，这并不是造成水颜色的原因。,The water molecule has three fundamental modes of vibration, including two stretching vibrati

7、ons of the O-H bonds which occur at v1 = 3650 cm1 and v3 = 3755 cm1. Absorption due to these vibrations occurs in the infrared region of the spectrum. The absorption in the visible spectrum is due mainly to the harmonic v1 + 3v3 = 14,318 cm1, which is equivalent to a wavelength of 698 nm.1 水分子有三个基本的

8、振动模式,包括发生在v1 = 3650cm1和v3 = 3755cm1的两个伸缩振动的o - h键。（光的）吸收是由于在这些红外光谱区域发生的振动。在可见光谱中的吸收主要由于谐波v1 + 3 v3 = 14318cm1,相当于698nm的波长。,Absorption intensity decreases markedly with each successive overtone, resulting in very weak absorption for the third overtone. For this reason, the pipe needs to have a length

9、 of a meter or more and the water must be purified by microfiltration to remove any particles that could produce Rayleigh scattering. 下一个后续的谐波（泛音）吸收强度显著降低,这也导致第三个谐波（泛音）的吸收非常的弱。因为这个原因,管需要有一个长一米以上的和必须被微细过滤任何可以产生瑞利散射（入射光在线度小于光波长的微粒上散射后散射光和入射光波长相同的现象。）的粒子的纯净水。,When water is in small quantities (e.g. in

10、a glass) it appears colorless to the human eye,Color of lakes and oceans Lakes and oceans appear blue for several reasons. One is that the surface of the water reflects the color of the sky. While this reflection contributes to the observed color, it is not the sole reason. 湖泊和海洋出现蓝色的有以下几个原因。一是水面反映出

11、天空的颜色。虽然这种反射会导致观察到的颜色,它不是唯一的原因。 .,Large bodies of water such as oceans manifest waters inherent slightly blue color.,Some constituents of sea water can influence the shade of blue of the ocean. This is why it can look greener or bluer in different areas. Water in swimming pools (which may also conta

12、in various chemicals) with white-painted sides and bottom will appear as a turquoise blue. Clean water appears blue in white-tiled swimming pools as well as in indoor pools where there is no blue sky to be reflected. The deeper the pool, the bluer the water. 海水的某些成分会影响的海洋蓝色的色荫。这就是为什么它在不同的海域能看起来更绿或更蓝

13、。水在游泳池(可能包含各种化学物质)两边和底部会显示为翠蓝。 干净的水在铺白色瓷砖的游泳池以及室内游泳池显现出蓝色,在这些地方不会反射出蓝天的颜色。游泳池越深，水也越蓝。,An indoor swimming pool appears blue from above, as light reflecting from the bottom of the pool travels through enough water that its red component is absorbed. The same water in a smaller bucket looks only slight

14、ly blue。,Scattering from suspended particles also plays an important role in the color of lakes and oceans. A few tens of meters of water will absorb all light, so without scattering, all bodies of water would appear black. Because most lakes and oceans contain suspended living matter and mineral pa

15、rticles, known as colored dissolved organic matter (CDOM) light from above is reflected upwards. Scattering from suspended particles would normally give a white color, as with snow, but because the light first passes through many meters of blue-colored liquid, the scattered light appears blue. In ex

16、tremely pure wateras is found in mountain lakes, where scattering from white-colored particles is missingthe scattering from water molecules themselves also contributes a blue color.,悬浮粒子的散射在湖泊和海洋的颜色中也发挥了重要作用。如果没有散射，几十米的水将会吸收掉所有的光,所有的水域将会显现出黑色。因为大多数湖泊和海洋含有悬浮生命物质和矿物粒子,称为有色溶解有机物(CDOM)，会把上面的光向上反射。悬浮粒子的

17、散射通常会反射白色,如雪一样,但由于光线先穿过了好几米的蓝色液体,因此散射光显现出蓝色。在非常纯净的水中，比如山地湖，白色粒子发出的散射消失了,水分子本身的散射也会造成水的蓝色。,Another phenomenon that occurs is Rayleigh scattering in the atmosphere along ones line of sight: the horizon is typically 45 km distant and the air (being just above sea level in the case of the ocean) is at i

18、ts densest. This mechanism would add a blue tinge to any distant object (not just the sea) because blue light would be scattered into ones line of sight. 另一个原因是瑞利散射发生人们在大气层中的视线:地平线通常是4-5km远和空气(相对于海洋略高于海平面)在那里最密集。这个原理将给任何遥远的对象(不仅仅是海)增加一点淡蓝，因为蓝光会散散到每个人的视线中。,The surfaces of seas and lakes often reflect

19、 blue skylight, making them appear bluer. The relative contribution of reflected skylight and the light scattered back from the depths is strongly dependent on observation angle. 海洋和湖泊的表面常常反映出天空的蓝色,这使其显得更蓝。反映天空的蓝色和从深处散射回来的光对水的颜色的贡献程度强烈地依赖于观察角度。,The hue of the reflected sky also contributes to the pe

20、rceived color of water.,Color of glaciers Glaciers are large bodies of ice and snow formed during very cold climates by processes involving the compaction of fallen snow. While snowy glaciers appear white from a distance, up close and when shielded from direct ambient light, glaciers usually appear

21、a deep blue due to the long path lengths of the internal reflected light. 冰川是在非常寒冷气候下落雪的凝结而形成的冰雪结构的主体。虽然被雪覆盖的冰川从远处看是白色的,但当靠近它并且屏蔽来自环境的直接光照,冰川通常由于内部反射光的长光程长而显现出深蓝色。,Color of water samples Dissolved and particulate material in water can cause discoloration. Slight discoloration is measured in Hazen un

22、its (HU). Impurities can be deeply colored as well, for instance dissolved organic compounds called tannins can result in dark brown colors, or algae floating in the water (particles) can impart a green color. 在水中溶解的和颗粒的物质会引起水的变色。轻微变色以色度单位。 杂质也可以加深颜色,例如单宁酸，它溶解有机化合物称为，可以导致深棕色,或漂浮在水中的藻类(粒子)可以造成水显绿色。,T

23、he color of a water sample can be reported as: Apparent color is the color of the whole water sample, and consists of color from both dissolved and suspended components. 2.True color is measured after filtering the water sample to remove all suspended material. 一份水样的颜色可以被报告为: 1.表面的颜色是整个水样的颜色,由溶解部分和悬

24、浮部分共同组成。 2.真实的颜色是测量过滤掉水样所有的悬浮物质后的颜色。,Testing for color can be a quick and easy test which often reflects the amount of organic material in the water, although certain inorganic components like iron or manganese can also impart color. 可以通过水中的有机物质数量反馈来快速、简洁地测量水的颜色,尽管某些无机成分，如铁和锰也可以影响水的颜色。,Water color c

25、an reveal physical, chemical and bacteriological conditions. In drinking water, green can indicate copper leaching from copper plumbing and can also represent algae growth. Blue can also indicate copper, or might be caused by syphoning of industrial cleaners in the tank of commodes, commonly known a

26、s backflowing. Reds can be signs of rust from iron pipes or airborne bacteria from lakes, etc. Black water can indicate sulfur reducing bacteria growth inside a hot water tank set at less than 120 degrees Fahrenheit. This usually has a strong sulfur or rotten egg (H2S) odor and is easily corrected b

27、y draining the water heater and increasing the temperature to 120 or higher. Care should be taken if children or the elderly will be using the hot water. The odor will always be in the hot water pipes if sulfate reducing bacteria are the cause and never in the cold water plumbing. The color spectrum

28、 with water indicators is wide and, if learned, can make solving cosmetic, bacteriological and chemical problems easier to identify.,水的颜色可以显示物理、化学和细菌的情况。在饮用水中，绿色表明铜从铜水管溢出,还可以代表藻类的生长。蓝色也可以表明水中有铜，可能是由于虹管吸收了工厂废水池中的水,通常被称为回流。红色表明铁管中的有铁锈或来自湖泊的细菌等。黑色的水可以表明在一个设定在低于120华氏度热水箱中硫酸盐还原菌的增长。这通常有很多的硫磺或很重的臭鸡蛋气味 (H2

29、S) ,这可以通过排掉热水器中的水和把温度升高到至少120度轻松地解决。当孩子或者老人使用热水时要小心。如果是硫酸盐还原菌是引起这种气味的原因，那么这种气味将永远在热水管道而不会在冷水管道。水作为色谱的指示器有广泛的适用面,如果研究的话,可以使解决化妆品、细菌和化学的问题更容易确定。,High concentrations of dissolved lime give the water of Havasu Falls a turquoise color.,Water quality and color The presence of color in water does not neces

30、sarily indicate that the water is not potable. Color-causing substances such as tannins may be harmless. 水中存在颜色并不一定表明水是不能饮用的。致色物质，例如单宁，也可能是无害的。,Color is not removed by typical water filters; however, slow sand filters can remove color, and the use of coagulants may also succeed in trapping the color

31、-causing compounds within the resulting precipitate. 颜色是不会被典型的过滤器清除的;然而,慢砂滤器可以清除水的颜色,使用混凝剂或许也能成功聚集致色化合物生成沉淀.,Other factors can affect the color we see: 1.Particles and solutes can absorb light, as in tea or coffee. Green algae in rivers and streams often lend a blue-green color. The Red Sea has occa

32、sional blooms of red Trichodesmium erythraeum algae. 2.Particles in water can scatter light. The Colorado River is often muddy red because of suspended reddish silt in the water. Some mountain lakes and streams with finely ground rock, such as glacial flour, are turquoise. Light scattering by suspen

33、ded matter is required in order that the blue light produced by waters absorption can return to the surface and be observed. Such scattering can also shift the spectrum of the emerging photons toward the green, a color often seen when water laden with suspended particles is observed.,其他会影响水的颜色的因素: 1

34、.粒子和溶质可以吸收光,如茶或者咖啡。绿藻经常使河流和小溪增添些蓝绿色。红海偶尔会爆发红海束毛藻。 2.水中的粒子可以散射光线。科罗拉河由于水中悬浮的红色泥沙，因此常常是泥泞的红色。一些山中的湖泊和有碎岩的溪流，如岩粉，是蓝绿色的。悬浮物对光的散射是必需的,以便水吸收光谱所产生的蓝光可以返回到水面以被观察到。这种散射还可以把新兴光谱转向绿色，当水中充满了悬浮颗粒就会被经常观测到。,Glacial rock flour makes New Zealands Lake Pukaki a lighter turquoise than its neighbors.,Color names Various cultures divide the semantic field of colors differently from the English language usage and some do not distinguish between blue and green in the same way. An example is Welsh where glas can mean blue or green. 与英语语言使用的差异的是不同的文化把颜色划分成不同的词义场和有些不区分蓝色和绿色。比如威尔士,glas可能意味