First, choose the herbicide variety on the road. There are many varieties of herbicides, such as stem and leaf treatment agents, soil treatment agents, contact herbicides, and natural herbicides. Some apply to pre-emergence weeding, and some apply to stem and leaf weeding. Therefore, weeds should be selected according to different crops and different periods.
Second, choose the correct method of use. Fluoride is easily photolyzed and must be sprayed on the surface of the soil and then covered with gums. The cable can be applied before emergence and after emergence. Duer, refined and can be used in the weed seedling stage, as long as the concentration is appropriate, it is safer for crops.
Third, protect crops from harm. Fields with more monocotyledonous weeds should choose herbicides that kill monocotyledonous weeds, and fields with more dicotyledonous weeds should choose herbicides that kill dicotyledonous weeds. For the field where the monocotyledonous and dicotyledonous weeds are mixed, the herbicide which can mainly kill the mixed weeds should be selected, but it should only be applied in the early stage of crop growth and the stage of weed initiation.
Fourth, according to different ecological environment. The application of herbicidal ether under strong light is better, but trifluralin is more volatile and reduces the efficacy. Under high temperature conditions, due to the strong herbicide activity, the dosage should be reduced; as the temperature changes, the dosage can be applied according to the actual application. The soil treatment agent has a good application effect when the soil moisture is high. Soils with high organic matter content should be appropriately increased in dosage due to strong adsorption of herbicides. Sandy soil has good grass killing effect, but the phytotoxicity is also heavy, and the dosage should be reduced.
Fifth, the use of comprehensive supporting measures to prevent weeds. Although chemical weeding has a good effect, it has many kinds of weeds, long growth cycle, strong vitality, and often resurrects. In order to improve the effect of killing grass, one must do the early and the small; the second is to eliminate the weeds around the field; the third is to deep ploughing to remove the perennial deep root weeds; the fourth is to plough and annihilate the annual weeds.
Huaxian County Fertilizer Station Yue Xiuli
1, strong, thermostable
Because CPVC compares PP-R, PE-X to be firm. Compared with PP, the PE-X tube, under the similar pressure, CPVC may use a smaller caliber to achieve the same water flow, thereby saving material costs and installation time. Compares with other thermoplastic, CPVC has the remarkable mechanical property under the different temperature, is suitable for the bearing the situation, the application temperature may reach as high as 93°C, the life may amount to 50 years.
2, easy installation
The connection method are very similar with PVC. Most commonly used and simple connection method is resolver cementation. Other connection methods are threaded connection, flange connection and electrode connections.
3, non-corrosive oxygen permeability
CPVC have the anti-oxygen, therefore the oxygen seepage from the radiator will not bring metal corrosion.
4, reducing the infiltration of additives
In order to prevent oxidation, some modified plastics needs to increase the massive antioxidant that may be infiltrated into the water supply system ,causing the ill-smelling smell.
5, without the impact of chlorine in water
A lot of polyolefin materials (including PP, PE) may be decomposed with water, while CPVC is not affected by the impact of residual chlorine in water that there is no cracks and leakage.
6, good flame retardancy
CPVC limiting oxygen index is 60, therefore it will not burn in the air. It has the characteristics : misfires the flame decoction,not to increase the fire set,restrict flame spread,low smoke generation. 7, CPVC has excellent chemical resistance to non-polar strong acid and alkali. Commonly used to substitute the metal to process the corrosive material, such as the poor quality of water, acidic material alkaline matter and other peroxide solutions.
8, the low thermal conductivity
CPVC thermal conductivity is only 1.05. heat is not easy to disseminate from the pipeline, heat loss of pipeline is low.
9, bacteria breeding is not easy
CPVC is not influenced by the impact of residual chlorine in water. So it will not result in cracks and leaks. Inner wall of pipe is smooth, not easy to breed bacteria. The research indicated that the breeding of germs in CPVC pipe is far lower than other materials such as copper, steel and other plastic pipe.
10, low thermal expansion
CPVC thermal-expansion coefficient is lower than other plastics. The tube expansion is very small when tube-pass heat, unlike other types of channels (such as PP-RRP) due to the higher temperature caused by heat expansion coefficient that could cause snake bending,the existence safe hidden danger and eyesores.
11, the test of time
none of a thermoplastic material such as CPVC,avoid the maintenance after 40 year hot water system's test, and displays its excellent performance
CPVC
CPVC Fittings,CPVC Pipes,Chlorinated Polyvinyl Chloride,CPVC Tubing
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