What are the characteristics of China's climate? What is the impact on China's production and life?

What are the characteristics of China's climate? What is the impact on China's production and life?

China's climate is mild in winter and rainy in summer, which is of great significance to the cultivation of rice and other crops

What is the impact of complex and diverse climate on China's life and production

It is beneficial to the diversified management of crops. All kinds of crops have the climate environment for growth. The amount of precipitation is different. The north is mainly dry land, and the staple food is wheat and corn. The south is mainly paddy field, and the staple food is rice. The northwest and other places are mainly animal husbandry and oasis agriculture

This paper briefly describes the impact of overpopulation on resources, environment, economy and life

According to the details of our country, China's most ecological population is 700 million, the largest ecological population is 1.5 billion. That is to say, only from the natural environment, China's most suitable population is 700 million, more than 700 million will cause too much pressure on the ecological environment, causing damage

What is the impact of climate on human life
It should be scientific

1. Climate affects people's clothing, food, housing and transportation (such as South boat, North horse, etc.)
2. Climate has an impact on the materials and style of traditional buildings (such as house structure, house orientation, building height, etc.),
Thickness of wall, etc
3. Climate has influence on people's eating habits (Guangdong likes tea, Hunan likes spicy, northeast likes garlic, pasta, etc.)
4. Climate disasters (such as cold wave, typhoon, hail, flood, drought, etc.) bring great damage to people's lives

Comparison of different methods for determination of protein content

The determination of protein content is one of the most commonly used and basic analytical methods in biochemical research. At present, there are four classical methods in common use, namely, nitrogen determination method, biuret method, Folin phenol reagent method and ultraviolet absorption method

What are the common methods of protein content determination, and their advantages and disadvantages

The sensitivity of Kjeldahl method is low. It is suitable for 0.1.0 mg of nitrogen with an error of ± 2%. It takes 10 hours to convert protein nitrogen into ammonia and titrate non protein nitrogen after acid absorption

Ultraviolet can produce ozone, and ozone can absorb ultraviolet. What's the use of ultraviolet germicidal lamp?

The frequency range of ultraviolet is relatively large, some ultraviolet can produce ozone, some ultraviolet can be absorbed by ozone
To give an inappropriate example, people can make the environment better, people can make the environment worse

Why can ozone absorb ultraviolet rays

Ultraviolet light is also called "ultraviolet light". In the electromagnetic spectrum, the electromagnetic radiation located between violet light and roentgen ray (X-ray). The wavelength is about (4-39) × 10-6cm, which can not cause vision (i.e. beyond the visible light range). The material that visible light can pass through will strongly absorb some bands of ultraviolet light

Why can ozone absorb ultraviolet rays

The important role of stratospheric ozone
The atmospheric composition of the stratosphere depends on two factors: one is a series of complex processes caused by ultraviolet radiation in the solar radiation; the other is long-lived substances emitted from the ground and slowly transported into the stratosphere. Ozone molecule (O3) is the most important component of the stratosphere, which is concentrated in the range of 10-50km above the ground, The maximum concentration of ozone in the atmosphere at the height of 20-25km is equivalent to a gas layer with a thickness of about 0.3cm at standard pressure and temperature. The maximum concentration of ozone varies with geographical location and season. Generally, the maximum concentration of ozone in the equator is about 25km, and that in the middle latitude is about 20km, The ozone concentration in summer is higher than that in winter. The stratosphere is heated by ozone absorbing 200-320nm ultraviolet radiation. Ozone is the main heat source. Therefore, the vertical distribution of ozone in the stratosphere plays a decisive role in the stratosphere temperature structure and atmospheric movement
The existence of ozone in the stratosphere is very important for the earth's living materials, because it blocks the high-energy ultraviolet radiation from reaching the ground. Although the ultraviolet radiation in the sunlight only accounts for about 5% of the total energy emitted by the sun, it has great damage to the earth's living system, and the higher the energy, the greater the damage, Above the stratosphere, it is absorbed by the primary oxygen and molecular oxygen in the atmosphere. From EUV to wavelength = 290nm, it is generally called UV-C segment, which is completely absorbed by stratospheric 03 molecule. 90% of the radiation segment with wavelength of 290-320nm, called UV-B segment, is also absorbed by O3 molecule, which greatly reduces the intensity of its reaching the ground, The intensity of UV-B ultraviolet radiation from the ground will increase. Studies show that UV B can destroy the biological protein and gene substances DNA, cause cell death, increase the incidence rate of eight kinds of skin cancer, cause eye blindness by causing eye injury, inhibit the growth of plants such as soybeans, cucurbits, vegetables, and penetrate the deep water layer of 10m. According to the recent analysis of American scientists, if the UV-B intensity increases by 1%, the death rate of malignant melanoma in the United States will increase by 0.8-1.5%, and the yield of soybean will decrease by about 25%, The ozone layer has actually become the protective layer of the earth's life system
Ozone can also absorb visible light and 9-10 micron infrared light to heat the atmosphere. Therefore, the change of ozone concentration not only affects the temperature and movement of stratospheric atmosphere, but also affects the global heat balance and global climate change
In the past two decades, it has been gradually recognized that some trace elements in the stratospheric atmosphere, such as chlorine, hydrogen free radicals and nitrogen oxides, can catalyze the decomposition of stratospheric ozone, and some human activities can directly or indirectly supply these species to the stratosphere, The stability of stratospheric ozone is threatened. This has become one of the most concerned environmental problems in the world for more than ten years. Especially in 1985, scientists from the British Antarctic Observatory, such as Farman, observed a sharp decrease in ozone over Antarctica in early spring at Halley Bay station, that is, after the formation of the so-called ozone hole, The problem of ozone depletion in the atmosphere has attracted more and more attention all over the world. The research on the physical or chemical causes of ozone depletion, the ecological consequences caused by ozone depletion, the model prediction and control measures of ozone concentration distribution has become an important topic in atmospheric science, meteorological science, environmental science, ecology, medicine and other fields

Why can carbon dioxide and water vapor absorb infrared rays and ozone absorb ultraviolet rays?

Because molecules can vibrate and rotate. Generally speaking, the energy of vibration and rotation is relatively low, so the energy absorbed during energy level transition is also relatively low, that is, the light with low frequency just lies in the infrared region, so it can absorb infrared. All molecules can absorb infrared, and most of them can be measured. Therefore, infrared spectrum is one of the four major spectra in spectral analysis
The absorption of ultraviolet light by ozone is related to the electronic energy level transition of ozone. The energy absorbed by electrons from one energy level orbit to another is generally higher. The frequency of light is located in the ultraviolet region, so it can absorb ultraviolet light. Similarly, many things have ultraviolet absorption, so ultraviolet absorption is one of the four major spectra in spectral analysis, Specific frequency is different
Its theoretical basis is quantum mechanics in physics. This involves many principles, such as the energy level is quantized, the frequency of absorbed light is selective, and so on