Brief of Filter Membrane Vacuum Filter System,Syringe Filter,Bottler Top Filter Zhejiang Sorfa Medical Plastic Co., Ltd. (Ningbo Jiangdong Aron Imp&Exp. Co.LTD) , http://www.sorfapipettes.com
PES (polyether sulfone) is high chemical, thermal stabile and has fast-flowing ability, acid and alkali resistant ability ( PH range 1-14), with high mechanical strength.
MCE is the mixture of cellulose nitrate and cellulose acetate which is hydrophilic, chemical compatible and has a high amount of protein adsorption. Generally, it applies to particle analysis, particle place, biochemical analysis, HPLC sample preparation and solvent filtration.
PVDF (polyvinylidene fluoride) has chemical stability and inertness which is applicable to chemically aggressive organic solvents, strong acids and alkali solution and sample preparation of HPLC (high performance liquid chromatography) analysis. It`s hydrophobic to filter off moisture in the air, gases and is laminated on supporting net for its strong strength, operability. Preferably, it`s resistant to a high temperature of 130 degrees.
NYLON (organic nylon 66) is applicable in most organic solvents and aqueous solution, for instance, organic solvents of strong acid, 70% ethanol and methylene chloride. It has good strength, chemical stability and high temperature resistant ability.
Generally ideal ponds require large areas, deep pool water, adequate illumination, smooth water sources, fertile water, and convenient transportation, in order to facilitate the growth of fish and increase production, and to facilitate production management. Specifically, it should have the following aspects: 1. Area and water depth. The size and depth of the pond have a very close relationship with the level of fish production. Production practice shows that the area of ​​adult fish ponds is 4-5 mu and the water depth is preferably 2-3 meters. The area of ​​the fish ponds can be below 5 mu with a water depth of 1.5 meters. 2, soil and sediment. Most of the fish ponds are excavated and built, and soil quality has a great impact on water quality. The best soil in the pond is black soil, followed by clay and sand. After a period of time, the ponds develop a thick layer of silt, which is a mixture of residual feed, fertilizer, fish dung, and dead organisms, which are mixed with mud and sand at the bottom of the pond. There is a certain amount of silt in the pond, and pond water tends to become fat, which is good for fish farming and high yield. However, too much sludge will deteriorate water quality, affect the growth of fish, and even cause the death of fish. Therefore, excess silt must be removed in time to maintain good water quality. 3, water and water quality. Good water quality requires sufficient dissolved oxygen, moderate pH (pH 7-8.5), good water temperature (preferably 25-30°C), abundant nutrient salts, and water quality (water color is mungbean, yellow-green, yellow-brown And light soy sauce, the transparency of 25-30cm), does not contain toxic substances. 4, the shape and direction of the pond. The shape of the pond is preferably rectangular. The length-to-width ratio is 2 to 3:1, and the length of the broad sides is 30 to 50 meters to facilitate management and pull fishing. The direction of the pond is suitable for east-west direction, which is conducive to prolonging sunshine hours, and is beneficial to plankton in the water and increasing dissolved oxygen. There should not be high mountains and tall trees shaded around the pond. 5, layout and matching. The pond base should not be too narrow, and it should generally have a base surface of 2 meters or more. When building a supporting poultry barn, the requirements should be wider. At the same time, it is necessary to build a perfect irrigation and drainage system so that each fish pond can be independently drained and drained to avoid string pool irrigation. The bottom of the pond should be tilted from the side of the irrigation to the side of the drainage so as to drain the pond. At the same time, power supply problems should be considered in order to use an aerator.