water

water ( Chemical formula H:) by O hydrogen , oxygen Two kinds of elements Inorganic materials No. Under normal temperature and pressure for colorless transparent liquid , known as human life The source . Water, including natural water ( Rivers , lake And gas Water, sea Water and underground water containing impurities) {}, distilled water yes Purified water Artificial, water (by reacting with hydrogen and oxygen atoms from water). Water is one of the most common substances on earth, including humans, inorganic compounds, all life's important resources, is the most important part of the organism. Water plays an important role in the evolution of life. It is a kind of special generalized non renewable, renewable resources.
water
pure water Can be conductive, but very weak (conductivity can be ignored in daily life), is very weak Electrolyte . In daily life due to water Dissolution The other Electrolyte And while more Ion , Conductivity Enhance。

water name

water Officially named

according to IUPAC Regulations, H Two O The official name of only two water molecules
 water water
(Water) and siloxane (Oxidane).

water Folk name

According to the chemical formula, and water the following nicknames: Hydrogen peroxide , A two hydrogen oxidation ;
Group VIA and group VIIA analogy of other compounds named rule: acid and oxygen and oxygen;
The analogy of metal hydroxides (base) naming rules: Hydrogen peroxide Caustic, hydrogen, hydroxyl hydrogen and hydrogen hydroxide.
The name is different, but the description is the same substance - water. Foreign countries have had a water called" A two hydrogen oxidation "Spoof article, caused an uproar, is the people to water these" offbeat named "do not understand the cause.
Although according to the water Chemical formula More than reading, but only IUPAC The provisions of the "water" and "silicone" is the formal name, used in formal occasions not other scientific name. The attribute in the "water" front, can be used to distinguish the special types of water, for example distilled water , Deionized water or heavy water .

water Inventory

Official name: water, alkyl
Folk Name: Poly hydrogen anhydride, caustic hydrogen cyanide, zero aldoxime, a two hydrogen oxidation, hydrogenation of detosylation sulfuric acid, hydroxyl hydrogen, decarburization decarburization glucose, decarbonylation of formaldehyde, formic acid, oxygen generation of hydrogen sulfide, hydrogen peroxide, hydrogen hydrogen hydroxide, two ether, zero alcohol, phenol hydrogen, hydrogen carboxylic acid. The 20 is alkyl, ether, ethylene oxide, hydrogenated poly acyl superoxide, two hydroxyl ester acid anhydride, oxidation, hydrogenation of benzyl benzyl alcohol, hydroxyl acid decarboxylation, hydrogenation denitrification nitrate, hydrogen cyanide thiocyanate

  

water source

water Summary

earth yes solar system The eight planets only covered by liquid water in the planet.
The origin of earth's water and there are big differences in the academic circles, there are dozens of different water formation theory. At some point in the early stage of the earth, hydrogen and oxygen to form water in the atmosphere of the original, Steam Setting down and gradually formed ocean ; there is a view that the formation of earth nebulosities existed before the composition of water in central plains.
Another view of the original crust silicate Other material Volcano The influence of reaction and precipitation of water. There is also a view, attracted by the earth's comet And the meteorite is the main source of water on the earth, and the earth's water is also constantly increasing.
When we open the map of the world, or when we face Globe When present in most of the area we are in front of the bright blue. Look at the earth from space, the earth we live in is very round, because the earth's equatorial radius than the polar radius of only 0.33%. The earth is a very beautiful blue ball. The water surface of the earth is the largest number of natural substances, it covers more than 71% of the earth's surface. The earth is a worthy of the name big water polo.

water viewpoint

Self said
1 of the earth from the original Nebula coagulate into the planet, due to internal temperature The change of gravity and matter, differentiation and convection, so the earth is divided into layers, in the process of differentiation, the hydrogen and oxygen gas float to the surface, and then through a variety of physical and chemical interaction to generate water;
The 2 is in the water basalt When the formation of the original crust melting after cooling. The first earth is a cold ball. Since then, due to the presence of the earth's interior radioactive elements such as uranium and thorium began to decay, releasing heat. Therefore, the interior of the earth material began to melt, high melting point material easy to sink, the molten material rises, separating the volatile substances from: nitrogen, oxygen, sulfur, carbohydrate and a large amount of water vapor, the test proved to be 1 m The granite melt, can release 26 L water and many completely volatile Chemical compound ;
Rich in water, 3 magma deep underground experiments show that the pressure is 15 kPa, the temperature of 10000 DEG C Magma 30%, can be dissolved in water. The average water content 6% magma volcano craters, some up to 12%, and more to the depths of the earth more moisture. Accordingly, some people according to the number of earth magma speculated on earth exists within 4 billion 500 million years, half of the deep water up to the release of the modern global magma ocean water;
 water water
4 volcano releases large amounts of water. From the modern volcano, almost every volcano has about 75% of the water vapor will be ejected. The water vapor column 1906 Vesuvius volcano eruption has been as high as 13000 meters, 20 h. 000 smoke Valley Alaska Carter Wallace Fire Mountain, there are tens of thousands of natural water vapor jetting hole, the average per second can spray 97 ~ 6450C water steam and hot water for about 23000m . According to some people think that, in all of the history of the earth, the total amount of solid material thrown out of the volcano for half of all of the lithosphere, volcano water can also be accounted for half of the modern global ocean water;
5 of the earth's internal mincrals part of the water, or the release of carbon monoxide, carbon dioxide and other gases at high temperature with hydrogen to form water. In addition, hydrocarbon combustion can also generate water in hard igneous rock, inclusions also crystal water amount and raw water.
Exogenous said
1 people in the study of chondritic composition, which contains a certain amount of water, generally From 0.5 to 5% Some, as high as 10%, and carbon Chondrite water more. Chondrite is one of the most common in the solar system Meteorite That accounts for about 86% of the total of all meteorites. Generally, the most primitive meteorites are the sun early condensate, the other planets of the earth and the solar system is composed of the spheres Meteorite condensation A;
Two solar wind To reach the earth's atmosphere layer, bring a lot of carbon, oxygen, hydrogen nuclear nuclear nuclear etc. Atomic nucleus These, electronic and atomic nuclei in the atmosphere with hydrogen atoms, carbon atoms and oxygen atoms. Through different chemical reactions into water molecules, it is estimated that in the earth's atmosphere high, almost every year to produce 1.5 T "Cosmic water" . Then, the water in the rain, Snow The fall to earth.
Scientists in 3" Deep impact "In the January 13, 2005 hit Tempel 1 The nucleus after splashing substances found in ice, two - three hundred million years ago, because Jupiter and Saturn Two. gas giant The immense gravity in their stars when renju, The Oort Cloud The comet was pulled into the inner solar system, the earth is also affected by the impact of a comet, research shows that most of the comet is composed of Cosmic dust Gas, ice composition, Ceres this one comet Contains more water than all the water on the earth, a comet through the atmosphere will melt into water, rain, snow and other forms to fall to the ground.

water Nature

water Three state changes

As everyone knows, there are three forms of water, respectively: solid state , liquid state , Gaseous .
But the water is only more than three states, and supercritical fluid, solid, superfluid fermionic condensate, Plasma state ,
Bose Einstein condensates and so on.

water Physics

 water water
Usually colourless , tasteless The liquid .
boiling point (C: 99.975 pressure For a Standard atmospheric pressure When is 101.375kPa).
freezing point C: 0
Triple point C: 0.01
Maximum relative density When the temperature of 3.982 DEG C:
Specific heat 4.186kJ/ (kg C) 0.1MPa 15 C: evaporation (kg) 0.1MPa 100 C 2257.2kJ/
density : the density of water at 3.98 DEG C, 1 x 10 Kg/m Water, at 0 DEG C, density is 0.99987 * 10 Kg/m Ice, at 0 DEG C, density is 0.9167 * 10 Kg/m .
critical temperature C: 374.2
Thermal conductivity In 20 degrees, the water conductivity is 0.006 J/s - cm - K,
Ice thermal conductivity is 0.023 J/s - cm - K,
stay Snow The density is 0.1 * 10 Kg/m When the snow thermal conductivity is 0.00029 J/s - cm - K.
Buoyancy classification: suspension , Float Sinking, floating and sinking.
All kinds of physical parameters of water at different temperatures:
T
P
C
Lambda
A
temperature
pressure
Specific heat
Thermal conductivity
Thermal diffusivity
C
KPa
KJ/ (kg K)
W/ (m K)
10m/h
Zero
Zero point six one three
Four point two zero seven seven
Zero point five five eight
Four point eight
Ten
One point two two seven
Four point one nine one zero
Zero point five six three
Four point nine
Twenty
Two point three three three
Four point one eight two six
Zero point five nine three
Five point one
Thirty
Four point two Four Zero
Four point one seven eight four
Zero point six one one
Five point three
Forty
Seven point three seven three
Four point one seven eight four
Zero point six two three
Five point four
Fifty
Twelve point three three two
Four point one eight two six
Zero point six four two
Five point six
Sixty
Nineteen point nine one eight
Four point one eight two six
Zero point six five seven
Five point seven
Seventy
Thirty-one point one five seven
Four point one nine one zero
Zero point six six six
Five point nine
Eighty
Forty-seven point three four three
Four point one nine five two
Zero point six seven zero
Six
Ninety
Seventy point one zero one
Four point two zero seven seven
Zero point six eight zero
Six point one
One hundred
One hundred and one point three two five
Four point two one six one
Zero point six eight three
Six point one
One hundred and ten
One hundred and forty-three
Four point two two eight seven
Zero point six eight five
Six point one
One hundred and twenty
One hundred and ninety-eight
Four point two four five four
Zero point six eight six
Six point two
One hundred and thirty
Two hundred and seventy
Four point two six six three
Zero point six eight six
Six point two
One hundred and forty
Three hundred and sixty-one
Four point two nine one five
Zero point six eight five
Six point two
One hundred and fifty
Four hundred and seventy-six
Four point three two zero eight
Zero point six eight four
Six point two
One hundred and sixty
Six hundred and eighteen
Four point three five four three
Zero point six eight three
Six point two
One hundred and seventy
Seven hundred and ninety-two
Four point three eight seven eight
Zero point six seven nine
Six point two
One hundred and eighty
One thousand and three
Four point four two five four
Zero point six seven five
Six point two
One hundred and ninety
One thousand two hundred and fifty-five
Four point four six three one
Zero point six seven zero
Six point two
Two hundred
One thousand five hundred and fifty-five
Four point five one three four
Zero point six six three
Six point one
Two hundred and ten
One thousand nine hundred and eight
Four point six Zero Five Five
Zero point six five five
Six
Two hundred and twenty
Two thousand three hundred and twenty
Four point six four seven three
Zero point six four five
Six
Two hundred and thirty
Two thousand seven hundred and ninety-eight
Four point six eight nine two
Zero point six three seven
Six
Two hundred and forty
Three thousand three hundred and forty-eight
Four point seven three one one
Zero point six two eight
Five point nine

T
P
C
Lambda
A
temperature
pressure
Specific heat
Thermal conductivity
Thermal diffusivity
C
KPa
KJ/ (kg K)
W/ (m K)
10m/h
Zero
Zero point six one three
Four point two zero seven seven
Zero point five five eight
Four point eight
Ten
One point two two seven
Four point one nine one zero
Zero point five six three
Four point nine
Twenty
Two point three three three
Four point one eight two six
Zero point five nine three
Five point one
Thirty
Four point two Four Zero
Four point one seven eight four
Zero point six one one
Five point three
Forty
Seven point three seven three
Four point one seven eight four
Zero point six two three
Five point four
Fifty
Twelve point three three two
Four point one eight two six
Zero point six four two
Five point six
Sixty
Nineteen point nine one eight
Four point one eight two six
Zero point six five seven
Five point seven
Seventy
Thirty-one point one five seven
Four point one nine one zero
Zero point six six six
Five point nine
Eighty
Forty-seven point three four three
Four point one nine five two
Zero point six seven zero
Six
Ninety
Seventy point one zero one
Four point two zero seven seven
Zero point six eight zero
Six point one
One hundred
One hundred and one point three two five
Four point two one six one
Zero point six eight three
Six point one
One hundred and ten
One hundred and forty-three
Four point two two eight seven
Zero point six eight five
Six point one
One hundred and twenty
One hundred and ninety-eight
Four point two four five four
Zero point six eight six
Six point two
One hundred and thirty
Two hundred and seventy
Four point two six six three
Zero point six eight six
Six point two
One hundred and forty
Three hundred and sixty-one
Four point two nine one five
Zero point six eight five
Six point two
One hundred and fifty
Four hundred and seventy-six
Four point three two zero eight
Zero point six eight four
Six point two
One hundred and sixty
Six hundred and eighteen
Four point three five four three
Zero point six eight three
Six point two
One hundred and seventy
Seven hundred and ninety-two
Four point three eight seven eight
Zero point six seven nine
Six point two
One hundred and eighty
One thousand and three
Four point four two five four
Zero point six seven five
Six point two
One hundred and ninety
One thousand two hundred and fifty-five
Four point four six three one
Zero point six seven zero
Six point two
Two hundred
One thousand five hundred and fifty-five
Four point five one three four
Zero point six six three
Six point one
Two hundred and ten
One thousand nine hundred and eight
Four point six Zero Five Five
Zero point six five five
Six
Two hundred and twenty
Two thousand three hundred and twenty
Four point six four seven three
Zero point six four five
Six
Two hundred and thirty
Two thousand seven hundred and ninety-eight
Four point six eight nine two
Zero point six three seven
Six
Two hundred and forty
Three thousand three hundred and forty-eight
Four point seven three one one
Zero point six two eight
Five point nine
The change of water density
The density of water at 3.982 DEG C for 1000kg/m3, the maximum temperature is higher than 3.982 degrees (also can be ignored at 4 DEG C), the density of water decreases with the increase of the temperature, in the range of 0 ~ 3.984 DEG C, cold water heat up, the density increases with the increase of temperature.
The temperature (Celsius)
  
The density (
)
-30
  
Nine hundred and eighty-three point eight five four
-20 Nine hundred and ninety-three point five four seven
-10 Nine hundred and ninety-eight point one one seven
Zero Nine hundred and ninety-nine point eight three nine five
Four Nine hundred and ninety-nine point nine seven two zero
Ten Nine hundred and ninety-nine point seven zero two six
Fifteen Nine hundred and ninety-nine point one zero two six
Twenty Nine hundred and ninety-eight point two zero seven one
Twenty-two
  
Nine hundred and ninety-seven point seven seven three five
Twenty-five Nine hundred and ninety-seven point zero four seven nine
Thirty Nine hundred and ninety-five point six five zero two
Forty Nine hundred and ninety-two point two
Sixty Nine hundred and eighty-three point two
Eighty Nine hundred and seventy-one point eight
One hundred Nine hundred and fifty-eight point four
Note: less than 0 degrees Celsius for cold water, the other 1 are numerical standard under the pressure
The reason: mainly by the molecular arrangement decision. It can be said by the hydrogen bond Lead. Because the water molecules are very strong, can be combined into molecules through hydrogen bonding association. Liquid water, in addition to containing water molecules simple (H O), also contains molecular association (H O) and 2 (H O) 3, when the temperature is 0 degrees in the water freezes, most water molecules are in (H O) are molecular association 3, when the temperature rise to 3.98 DEG C when water molecules (101.375kPa) to (H O) there are 2 associated molecular forms, molecules occupy the space is reduced, the water density maximum. If the temperature continues to rise at 3.982 DEG C, thermal expansion and contraction of the material general laws which dominate the. The temperature dropped to 0 degrees centigrade, water freezes, the water freezes almost all molecular association together become a huge molecular association, in the arrangement of ice water molecules in each oxygen atom has four hydrogen atoms near the two hydrogen bonds this arrangement leads into is an open structure, the structure of ice large Gap So, the ice density The inverse temperature water.

water Chemistry

Chemical formula: H O
Structure type: H - O - H (two hydrogen oxygen Bond angle between 104.5 DEG).
Molecular weight: 18.016
Chemical experiment: water Electrolysis . Equation: 2H O= power =2H = +O = (decomposition)
Molecular structure: hydrogen atom , Oxygen atom .
CAS number: 7732-18-5
Water has the following properties:
1 stability : in more than 2000 DEG C to decomposition.
There are the following: the water ionization ionization equilibrium in water: H O== ==H +OH reversible or H O+H O= =H O reversible +OH.
Note: "H O for hydration Hydrogen ion In order to simple, often abbreviated as H, more accurate statement for H Nine O Four , hydrogen ions in water The amount of substance concentration 10 mol/L.
Oxidizing water 2 Water with more active metal or carbon reaction, oxidation performance, hydrogen reduction hydrogen .
2Na+2H O=2NaOH+H hav'e
Mg+2H O=Mg (OH): +H =
3Fe+4H O (water vapor) =Fe O +4H (heating)
C+H O=CO+H (high temperature)
The reduction of water 3 Water fluoride with elemental reaction, reduction of oxygen was reduced to oxygen
2F +2H O=4HF+O hav'e.
4 water Electrolysis :
The water in the DC function, decomposition hydrogen and oxygen Using this method, pure hydrogen and pure oxygen 2H O=2H = +O = industry.
5 hydration reaction :
Water with active metal Basic oxides And the most acidic oxides and some Unsaturated hydrocarbon Happen hydration reaction .
Na O+H O=2NaOH
CaO+H O=Ca (OH)
SO +H O=H SO
P O +3H O=2H PO
CH =CH +H O vs. C H OH
Six Hydrolysis reaction
Salt hydrolysis:
Nitrides Mg N +6H hydrolysis: O (heating) =3Mg (OH): +2NH =
NaAlO +HCI+H O=Al (OH): +NaCI (NaCI a)
Calcium carbide hydrolysis: CaC (carbide) +2H O (saturated sodium chloride) =Ca (OH) +C H hav'e
Halogenated hydrocarbon hydrolysis C: H Br+H O (sodium hydroxide solution under heating) vs. C H OH+HBr
Sodium alkoxide hydrolysis:
C H ONa+H O, C H OH+NaOH
The hydrolysis of esters:
CH COOC H +H O (copper or silver catalyst and heating) vs. CH COOH+C H OH
Polysaccharide hydrolysis: (C H O) n+nH O vs. nC H O
CH CH propionitrile hydrolysis: CN+H O, CH CH C (OH) NH
CH CH C (OH) NH+H O, CH CH C (OH) NH,
CH CH CONH +H O, CH CH COOH+NH
Hydrolysis of the amide: - CO - NH - +H - O - COOH+NH-
Six Water molecules The diameter of the order is -10 10, is generally believed that the water 2~3 is the diameter of the unit.
 water water
7 ionization of water :
Water conductivity is extremely weak, because water has weak ionization, dissociation of water there.
H O vs. H +OH
298.15K (i.e. 25 degrees Celsius) ion water area 10 .
8 water is amphiphillic Both the hydrogen ion (H,), also have hydroxyl ions (OH). But pure distilled water Is neutral.
9 the pH value of water: water at 25 DEG C, pH 7 (neutral), with the change of temperature is still neutral.

water Hardness

The daily water can be divided into Soft water and Hard water There are more soluble, soluble calcium and magnesium and iron salt water is called hard water. Water containing Ca Mg. The total concentration of plasma is called hardness. The hardness of the water unit of mol - M DM or mmol. . According to the hardness of the water can be classified as water:
The hardness of DM / (mmol. )
>4.5
3.0~4.5
1.5~3.0
0.5~1.5
<0.5
Name
very hard water
Hard water
fairly hard water
Soft water
Very soft water

The hardness of DM / (mmol. )
>4.5
3.0~4.5
1.5~3.0
0.5~1.5
<0.5
Name
very hard water
Hard water
fairly hard water
Soft water
Very soft water
The industry also has other definitions: 1dm MgO and CaO the total amount of water containing the equivalent of 10mg CaO is defined as 1 degrees of hardness, hardness in the above 8 degrees for hard water.
Containing HCO Three The water is called Temporary hard water When heated, bicarbonate ion decomposition makes the calcium and magnesium ions precipitate and softening.
Containing Cl SO. Four The water can be softened by heating, called Permanent hard water .
You can use soap water to distinguish soft hardness, can make soft boiled water

water The concept of classification

Groundwater and surface water
Groundwater, organic and microbial pollution less, and more ions dissolved, usually distilled water of high hardness and easy scaling; sometimes manganese fluoride exceed the standard can not meet the production and living water demand.
Surface water and groundwater is organic and microbial pollution more, if it is a limestone area, the surface water tend to have higher hardness, such as Sichuan, Deyang, Mianyang, Guangyuan, ABA and other regions.
Raw water and water purification
Raw water usually refers to water water treatment equipment, such as the commonly used city tap water, groundwater, surface water and other suburban field, often with the value of TDS (total dissolved solids content in water) to detect the water quality, Chinese city tap water TDS value is usually 100 ~ 400ppm.
Clean water: raw water through water treatment facilities after treatment is called water purification.
Pure water and distilled water
Pure water, raw water through reverse osmosis and sterilization device complete water treatment facilities after removal of the raw water in the vast majority of inorganic salt ions, microorganism and organic impurities, water can be directly drunk.
Distilled water, distilled water was prepared, not normally used for drinking.
Purified water and water for injection
Purified water, the pharmaceutical industry with pure water, <2 s/cm conductivity requirements.
The injection of water, water purification, multi effect distillation purification after ultrafiltration again removing pyrogen injection water can be formulated.
free water and Combined water
free water - also known as bulk water, water retention. That can flow freely in the organism or cells in the water is a good solvent and transport. The water in the cells with free water and bound water ( Combined water There are two states), because there are different, their characteristics are also different. Free water total water content ratio is greater, the Protoplasm The viscosity is small, and a sol state, more vigorous metabolism.
Combined water Is the water in the Biology Body and Cells One of the existing state of adsorption and binding in organic solids on the water, mainly depends on the hydrogen bond and Protein The polar group ( carboxyl and amino The combination of water formed colloid).

water Access method

water Underground water

The streams and rivers for water is the first choice of surface already dry river bed area. Although these places The surface Already anhydrous, but often found in their surface rich The groundwater .

water In distilled water

The method is especially suitable for solar distillation in desert, dig a long 90 cm wide, 45 cm deep hole in the ground, put a central pit at the bottom of the kettle, put a piece of plastic film in the pit, with the surrounding rock or sand will be fixed in the film along the pit, and then in the plastic film
 Solar distillation Solar distillation
The central part of a hanging stone to ensure plastic film is arc, so that water droplets can slide smoothly to the bottom and fall into the collector.
The sun makes the temperature of wet air and soil pit increased, evaporation of water vapor. The water vapor saturated gradually, and Plastic Membrane contact cold condensation into water, down to the pot. This method of collecting about half a litre of water in a day can.

water Plants in water

adopt Coagulation Plant to collect water vapor. In a period of strong thick foliage trees twigs set in a plastic bag, the bag up to note when put in the bag, the bag in a corner down, so it is easy to receive the foliar transpiration of the condensation water. because Transpiration The water vapor rise in contact with the film when cold will condense into droplets. Should let the condensation film along the inner wall at the bottom of the inflow collector.

water refining treatment

(a) sediment filtration
(two) Hard water Softening method
(three) Active carbon adsorption
(four) deionization
(five) reverse osmosis method, Reverse osmosis
(six) ultrafiltration method
(seven) Distillation
(eight) Ultraviolet disinfection method
(nine) biological chemical method
(ten) the forward osmosis method, natural purification method of human creation.

water Forward osmosis

"Infiltration" in desalination of sea water, desalination, water treatment, and said it was tedious, complex permeability, or seep in and reverse osmosis, reverse osmosis, reverse osmosis method, difference of distinction or correspondence, stressed that the forward osmosis and reverse osmosis method is the inverse of a method. As a kind of forward osmosis purification and desalination technology of water potential, the world is a multi angle, the theory and practice of deep exploration.
With the rapid development of science and technology, pressure driven reverse osmosis membrane separation technology (RO) in the membrane, membrane components, equipment and technology and other aspects of a larger innovation and improvement, but more and more people are aware of the existence of RO technology in the field of energy saving, environmental protection and the limitations of RO technology can be considered in terms of desalination, peak close to the development of. Therefore, foreign countries have carried out the forward osmosis membrane separation technology (FO) related research, and achieved certain results, has been applied in seawater desalination, sewage treatment, food processing, medicine and other fields, especially the "pressure retarded osmosis (FRO) water power", it is a very promising the clean renewable energy development technology. But the forward osmosis membrane separation technology, very little attention, and the related research is not much. Although the last century in 90s our country has invented the "non pressurized adsorption osmosis" (CN92110710. 2).
A foreign liquid system in 1976, the original domestic attempt, 1992, forward osmosis invented liquid-solid system (non pressurized adsorption osmosis desalination (CN92110710). 2). Until about 10 years later, again followed the international trend, beginning the standard copy mode, in 2008 to start a review report.
Forward osmosis separation technology has been applied early. Long ago, people used salt to long-term storage of food, because in high salt environment, most bacteria fungi and pathogenic bacteria due to osmosis dehydration death or temporary loss of activity.
Today, people have begun to use the forward osmosis membrane separation technology Desalination of sea water , industrial waste water Study on treatment of landfill leachate treatment, etc.; the food industry in the forward osmosis membrane separation in the laboratory to concentrated drink; emergency rescue life support system using forward osmosis membrane separation technology for producing fresh water. With the development of material science, medicine forward osmosis technology has been applied to human controlled release.

water Biological methods

The film guide hole with water molecules through the cell membrane of living cells. Protein To form.

water Influence

water On climate

Water has a moderating effect on the climate. Water vapor in the atmosphere can block 60% of earth's radiation, protect the earth not to be cooled. Marine and terrestrial water can absorb and accumulate the heat in the summer, the temperature is not too high; in the winter can slowly release heat, so temperature is not too low.
The ocean and surface evaporation of water to form a cloud in the sky, the water molecules in the cloud reaches a certain quantity by precipitation turned to rain down, then turned into snow in the winter. Drop in on the surface of the water to seep into underground water formation; groundwater out in formation from the formation of the spring, through streams and rivers into the sea. The formation of a water cycle [Note: the plant is also involved in the water cycle.
Precipitation activities form an important influence on the climate. In the temperate monsoon climate, summer monsoon brought abundant moisture, summer rainy winter, little rain, forming obvious wet and dry season two.
In addition, in nature, due to different climatic conditions, water will be to hail, fog, dew, frost and other emerging patterns and effects of climate and human activities.

water On geography

In 71% of the earth's surface is covered by water, from the air, the earth is a blue planet. Water erosion of rock soil, river erosion, sediment transport, and create a plain, changes in surface morphology.
The surface of the earth Water constitute the hydrosphere, including Wetland , ocean , Rivers , lake , Swamp , glacier , Accumulated snow , groundwater In the atmosphere and water. As the water into the ocean with some salt, plus the annual accumulation and evaporation, sea and ocean water is salt water, can not be directly consumed. Some lakes also contain saline water, such as: Dead Sea. The largest water in the world is the Pacific ocean. The five Great Lakes of North America is the largest freshwater system. Eurasia The Caspian Sea is the largest saltwater lake.
The water volume of about 1360000 cubic kilometers, 000. The ocean accounts for 1320000000 cubic kilometers (97.2%); glaciers and ice sheets accounted for 25000000 cubic kilometers (1.8%); groundwater accounts for 13000000 cubic kilometers (0.9%); lake, sea, river and fresh water accounts for 250000 cubic kilometers (0.02%); when the water vapor in the atmosphere at any given are accounted for 13000 cubic kilometers (0.001%).
The medicinal function of rain
The rain, also known as rootless water, the Chinese Medicine Clear light , sweet and light, the waters above also. Summer is a plus. Keep the drink. (just under the rain contains large amounts of dust, especially in the modern industry and the serious pollution of the city, the composition is very complex, even may contain pathogenic microorganisms. But in the unpolluted place, clean rainwater still function).

water On the project

1 ancient Chinese had to live and applied to agriculture: to ensure rice living environment is wet, they built in the field along the ridge, to prevent the loss of residual water in the field, which greatly improved the yield of rice. They also use shadoof, shaduf is a slender plus an upright shelf lever, which is the pivot, hang on the end of a heavy weight, front suspension bucket. When people put the bucket into the water to play with water, because the end of the lever of the gravity water can dip to the required place easily. Shadoof Early in the spring and Autumn period is quite popular, and lasted for thousands of years, is the general of the old rural China water lifting appliances.
The 2 ancient Assyrian king in the capital around full of rare plants. In order to irrigate the plant, he built a long Canal Used to, from water diversion irrigation near these plants.
In 3 Mexico There are many lakes the former capital of Tenochtitlan Portland around the scene, the Aztecs built the platform in the lake. They dug out the lake silt in the shop Field Then, a crop. The Aztecs dug ditches in the fields around, similar to the Chinese for irrigation in paddy field.
4 Israel in the desert, the desert accounted for 60% of the land area, not only arable land, and the arid areas, 1.5 rainfall, seasonal, regional uneven distribution of light water resource The problem of lack is extremely prominent, the need for the survival and development of a state laws that would declare water resources as public property, managed by specialized agencies. In addition to the construction of water conservancy, also vigorously develop water-saving technology. The basic need of common irrigation and furrow irrigation in agricultural production, Border method of irrigation Method。 At the end of 1970s before the use of sprinkler irrigation area, accounting for 87%, Drip irrigation Accounted for 10%. After 80s, the drip began to commonly used at the beginning of this century, the irrigation area accounted for 90%, mainly used for vegetables, fruits and flowers, cotton Such as planting. Investment is not high than drip irrigation, not only water, but also on the topography, soil, environmental adaptability, wind force and the influence of climate, fertilizer and Pesticides At the same time with the irrigation water application root, fertilizer saving drugs can also prevent secondary salinization, eliminate harmful salt in root zone. The use of drip irrigation technology, the crop yield doubled, Planting More than 90% of output from agricultural irrigation.

water On the human body

about people It is next to the water oxygen The important material. In adults, the quality of 60~70% is water . children The water in the proportion of larger, up to nearly 80%. If a person does not eat, only rely on their stored nutrients or consumption of autologous tissue, can live for a month. But if you do not drink water Even a week, time is very difficult. In 10% water loss health threat, such as loss of 20%, there are life Enough to see the water on the danger, significance of life.
The water and the treatment of common diseases, such as: in the morning a cup of cold white boiling water can treat splash; half an hour after a meal to drink some water, can be used to lose weight; massage with hot water is a powerful sedative, can alleviate insomnia; drink Dakoutaikou can relieve constipation; before a cup of water is good for the heart sick; you can use brine emetic.
1 dissolved digestive function
Water is the essential biochemical changes in all physiological processes in medium. Water has very strong solubility and ionization ability (water molecule polarity), can make the water soluble substances exist in dissolved state and ionic state, and even some fat and protein can also under appropriate conditions, dissolved in water, composed of emulsion or colloidal solution. Dissolved or dispersed in water substance is helpful for effective chemical reactions in the body.
The food enters the cavity and gastrointestinal digestion, rely on the secretion of the digestive organs, such as saliva, gastric juice, pancreatic juice, intestinal fluid, bile, to food digestion and absorption. In the digestion of water content as high as 90%.
2 participate in metabolic function
In the process of the human body The new supersedes the old., exchange of material and chemical reactions are carried out in the water. Water is not only the biochemical reaction medium, and the water itself is also involved in oxidation, reduction, synthesis, chemical decomposition reaction. Water is a variety of chemical substances in the body to ensure normal metabolism.
If the body has long been short of water, will make the abnormal metabolism, metabolism to slow down the excessive accumulation of energy and fat, make people fat.
3 carrier transport function
Because of the good water solubility, strong liquidity, and in various tissues in the body organs, water acts as a carrier of nutrients. In the transport of nutrients and gas absorption, transport and exchange, transport and excretion of metabolites, water plays an extremely important role. For example, oxygen transport, Vitamin , Glucose , Amino acid , enzyme To the body, hormone; urea , uric acid The metabolic waste to the kidneys and excreted in the urine.
4 regulation of inhibitory function
The specific heat of water is high, the effect on the body temperature regulation.
The best way is to drink plenty of water to prevent heatstroke. This is because that the three large capacity of nutrient intake in the presence of water, the use of oxygen for oxidative metabolism, energy release, and then through the evaporation of water can emit large amounts of energy, avoid high temperature. When the body is short of water, the excess energy is dissipated in time, causing heatstroke.
In addition, the water also can improve humoral tissue circulation, regulate muscle tension and maintain body osmotic pressure and acid-base balance .
5 lubrication moisturizing function
There is a risk of doing sports in the absence of water. Because the organs lack of water lubrication, easy to wear. Therefore, 1 hours before exercise is best to drink plenty of water.
in vivo joint , Ligament , muscle , membrane At the event, as by water Lubricant . The viscosity of water is small, can make the body lubrication friction parts, reduce friction and prevent damage to the organs in the body, and can make a flexible motion organ.
At the same time, water and moisturizing function, the cells of the body often in the wet state, keep skin supple. Regular replenishment, make the skin moist, particularly plump and elastic. It can be said that water is the beauty jiapin.
6 dilution and detoxification function
Do not love to drink water people tend to acne, this is because the human body must be involved in the detoxification of water. There is not enough water, it is difficult to effectively discharge the toxin, accumulate in the body, can easily lead to acne.
In fact, water not only has a good solubility, but also has important dilution At the same time, the renal excretion of water can be metabolic wastes, toxins and excess ingestion of drugs be discharged, reduce the intestinal absorption of toxins, prevent the harmful substances in the body of chronic accumulation Lead poisoning. Therefore, the medication should drink plenty of water, in order to effectively eliminate the side effects caused by drugs.

water Of plants

Plants need water to grow, water (and carbon dioxide) as raw materials in the Photosynthesis And, in the respiration of plants As a result of.

water contaminated

water classification

Water pollution has two kinds: one kind is the natural pollution; the other is man-made pollution. The harm of water pollution is. Water pollution according to the different impurity pollution mainly divided into chemical pollution, physical pollution and biological pollution in three categories:
A, chemical pollution
The contamination caused by chemicals for water pollution. According to the specific chemical pollution of impurity contamination can be divided into 6 categories:
(1) inorganic pollution substances: inorganic pollutants of polluted water with acid and alkali and some inorganic salts. Water pollution makes the pH change of the pH value, prevent water purification effect, corrosion will ship and underwater Building The impact of fishing.
(2) inorganic toxic substances: inorganic toxic substances in water pollution are the potential long-term effects of heavy metals and other substances, mainly mercury, cadmium, lead, arsenic and other elements.
(3) organic toxic substances: the main organic toxic substances in water pollution are various organic pesticides, polycyclic aromatic hydrocarbons, aromatic hydrocarbon. Most of them are synthetic material, Chemical property Very stable, it is difficult to be biodegradable.
(4) aerobic pollutants: carbohydrate, protein, fat and phenol, alcohol and other organic substances contained in sewage and some industrial wastewater can be decomposed under the action of microorganisms. Need a lot of oxygen in the decomposition process, called aerobic pollutants.
(5): mainly containing plant nutrients such as nitrogen and phosphorus nutrients of domestic and industrial wastewater, and residual nitrogen and phosphorus in farmland drainage.
(6) the oil pollutants: mainly refers to water and oil pollution, especially marine oil Tanker The worst pollution accident.
Two, physical pollution
Physical pollution including:
(1) suspended material pollution: suspended material refers to insoluble substances contained in the water, including solid material and foam etc.. They are produced by sewage, garbage and mining, quarrying, construction, food processing, paper making waste water discharged into farmland or Soil erosion Caused by the. The appearance of suspended material and effect of water, prevent water plant Photosynthesis And decrease the oxygen dissolved, harmful to aquatic organisms.
(2): thermal pollution from various industrial processes cooling water If not, take measures, directly discharged into water bodies, may cause the water temperature and dissolved oxygen, water in the presence of certain toxic substances increased toxicity and other phenomena, thereby endangering the fish and aquatic growth.
(3): due to radioactive contamination atomic energy The development of the industry, radioactive mineral resources exploitation, nuclear test and Nuclear power plant The establishment and application of isotopes in the field of medical, industrial, research, radioactive waste water, waste increased significantly, causing certain radioactive contamination.
Three, biological pollution
Hospital sewage, especially sewage and some industrial wastewater, often can bring some pathogenic microorganisms. For example, some pathogenic bacteria that exist in human and animal intestinal tract, such as Typhoid fever Paratyphoid fever, cholera bacteria, and so can people and animals Faeces The pollution into the water body, and spread with water flow. Some viruses, such as hepatitis virus Adenovirus, and are often found in polluted water. Some parasitic diseases such as schistosomiasis, amebic dysentery, leptospirosis can also spread through the water. Thus we see protecting the earth's environment, prevention of industrial pollution and water pollution of pathogenic microorganisms to protect the environment is a major issue, is to protect human health.

water processing method

1 of the waste water through sedimentation tank, the solid will settle down.
2 in the trickling filter, waste water can be filtered through the sand and gravel surface also can spread bacteria to decompose the waste in water.
3 also can be added to bleach water, such as chlorine to kill microorganisms.
4 water is discharged into the open ponds, natural purification.
5 wastewater after "spin water separator, filter.
Quartz sand filter is to remove the suspended solids in water is one of the most effective means, sewage treatment, sewage and the important unit in water treatment. Its role is to have the further removal of pollutants in water flocculation, it through the filter of interception, sedimentation and adsorption effect, achieve the aim of purifying water.
Two scope.
1 for living water and industrial water, municipal water supply system can meet the requirements of effluent turbidity than 5mg/L drinking water quality standards;
2, the removal of suspended solids in industrial wastewater solids;
3 can be used as ion exchange softening and demineralization system in the pretreatment equipment, coarse filtration equipment of water supply industry is not high on the water quality requirements;
And in swimming pool recycling system, cooling circulating water purification system.

water In view of the ancient world

In the early stages of civilization, people began to explore the world of all things or classification, in which water plays an important role. In our childhood, because of low level of scientific understanding, for lack of water, water properties cannot be explained from a scientific point of view, for water fire, can raise human, but can also be drowning, both rearing and destruction ability have a scared feeling, produced water worship The worship of nature, with superstition.

water Related links

The relationship between water and
In some areas, the annual flood season, regular news, this is a large amount of water, water, for each region in such a situation, we should use, dig library expansion dredging, flood storage, water storage, water conservation, surface, always flash floods, and Flood flood, water inflow law did not understand, anti water no, water storage, the result is when drought does not exist when the flood water.
Flood prone areas, should actively develop water storage and storage facilities, improve the natural ecological, adhere to the implementation, will improve the local ecological environment and climate, to be sustained, save alternate economic construction investment, forming a virtuous circle of ecological balance.
The total reserves of 1 billion 360 million cubic kilometers of water on earth, we usually say that the water resources are mainly on land, freshwater resources, fresh water accounted for only 9%; of which 97% of the fresh water stored in the south, the Arctic glacier. The human life is the most close of lakes, rivers and shallow underground water accounted for only 0.2% of the total reserves of fresh water.
See details River system Entry.
ice
Because the water molecules are hydrogen bond By this structure special association. According to the modern times X ray The study proved that the crystal structure of ice with tetrahedron. The tetrahedron is formed by hydrogen bonds, is an open structure relaxation, because five water molecules can not put all the tetrahedral volume, hydrogen bond in the ice to link these tetrahedron, as a whole. The directional hydrogen bonds formed by ordering the utilization rate of the space is small, accounting for about 34%, so the ice density is small, about 4 degrees Celsius when liquid water 9/10.
When dissolved in water to break up large numbers of hydrogen bonds, so that the whole group of water molecules into tetrahedron group and sporadic small "(some from the formation of molecular hydrogen bond association), the liquid water is not as ice is completely ordered, but disordered to a certain extent, i.e. Water molecules The distance between the ice is not as fixed as H O molecules can be made by a tetrahedron into another ceramics to ceramics. This gap between molecules is reduced, the relative density of ice will increase.
See ice Entry.
Supercritical water
When the pressure and temperature reaches a certain value (about 22MPa, 374 degrees Celsius), water at supercritical state. System temperature and pressure exceeds the critical point of water, known as supercritical water. Water and steam can not distinguish the critical point, become a present state of high temperature and high pressure of the new fluid . The supercritical fluid has many properties, such as strong oxidation ability, will need to handle the material in supercritical water, and the Dissolution Oxygen (can be dissolved), the oxidation resistance at potassium permanganate . The two is that many substances in which you can burning That burst into flames. Three can be dissolved a lot of material (such as oil), and dissolved volume greatly reduced, this is because the supercritical water at this time tightly wrapped around the oil. The four is that it can slowly dissolve corrosion Almost all metals, including gold (and even Aqua Similar). It is the super five Catalysis Effect of chemical reaction in supercritical water, very quickly.
See Supercritical water Entry.
Light water and heavy water
heavy water (heavy, water (deuteroxide) Deuterium oxide ) is composed of deuterium and oxygen Chemical compound . molecule D O, a molecular weight of 20.0275, compared with the ordinary water (H O) the molecular weight of 18.0153 higher than about 11%, so called heavy water . In natural water, heavy water The content of about 0.015%. Because the minimum property difference of deuterium and hydrogen, so heavy water And water is also very similar. Heavy water Ion product constant 1.6*10-15.
In order to heavy water The difference will be called ordinary water, light water. In the power reactor Moderator Mostly, light, heavy water The coolant and graphite; they are light water, heavy water, and helium gases. The only light is the most widely used in reactor coolant and moderator.
See details heavy water and Light water Entry