First, the fry cultivation and cultivation pool is generally a cement pool, with an area of ​​20 to 100 square meters, a depth of 1.2 to 1.5 meters, and ample water sources. Put the water in the pond 10 to 15 days before draining, remove the black silt at the bottom of the pond, and use 80 g of lime slurry per acre to disinfect the whole pool and disinfect it evenly. The water can be infused the next day after disinfection. The initial water level should be controlled at 80 cm to 100 cm, and then 250 kg to 350 kg of fully-fermented and disinfected manure should be placed per mu to facilitate the growth of bait organisms.
About 1 day after hatching, the fry can grow up to 1 cm in length and have been able to feed on copepods and cladocerans. At this time, fry stocking is started. Before stocking, several fryers were used to test the water for 24 hours, and they were stocked after normal conditions. Stocking densities range from 50 to 100 per square meter. When stocking, note that the water temperature difference cannot exceed 2°C. After fry stocking, deepen the pool water daily with micro-flowing water. Feeding more than 3 times a day, feeding plankton and egg yolk mainly in the first 5 days, feeding leeches and powdered feed from the 6th to the 10th day, and feeding peanut bran on the 11th to 30th days. Water squid and squid feed. Adhere to the patrol pond every morning and observe the water color. The transparency is generally controlled at about 30 cm. If there are too many plankton and the water quality is poor, the water should be changed appropriately to reduce the density of the food organisms and keep the water fresh. After about 30 days of cultivation, the fry generally grows to a size of 4 cm to 5 cm and can be placed in large pools for fingerling cultivation.
Second, the species of fish breeding fish breeding pond area of ​​1 mu ~ 3 acres is appropriate, water depth of 1.5 meters to 2 meters. Put about 150kg of quicklime and disinfect water per acre 7 days to 10 days before planting. Select stocks of individuals with a healthy body, no disease, no injury, and a size of 4 cm or more. Before soaking, fish seeds were soaked with 120 mg/L potassium permanganate for about 15 minutes, and the stocking density was 3 to 5 tails per square meter. It was better to feed whole grain feed containing more than 35% crude protein. The third day after the fish pool began to tame, the initial period of eating less, it is appropriate to feed a small amount of multiple, 5 days to 7 days, with the fish species into the normal food, the number of feeding should be reduced, every morning, Each time in the afternoon and evening, the daily feeding amount is 3% to 5% of the fish's body weight. After 10 days, the fish fry body is about 6 cm long, and the fish that feeds 80% of the principle is sufficient to leave. Because Chinese barbs have certain plant food habits, a small amount of fresh green material should be fed regularly to supplement part of the vitamins, which is beneficial to the growth of fish species.
Chinese barbs grow in a water environment with fresh water and high dissolved oxygen content. Each pond can be equipped with a 0.75 kW or 1.5 kW impeller aerator according to the size of the fish pond. In case of hot and rainy weather, special attention should be paid to observing the activities of fish species. In the event of signs of hypoxia, aerators should be turned on for oxygenation. Under normal circumstances, aerators are opened every morning and noon for 1 hour to 2 hours. The fish ponds are sterilized with quicklime every half month at an amount of 15 to 20 kilograms per mu to inhibit the growth of harmful bacteria and the decomposition of organic substrates to ensure the growth of fish species in a good water environment. After 100 days to 120 days of careful rearing, the species can grow from 4 cm long to 80 g to 100 g per tail, and the survival rate is usually over 90%.
A roundness tester is a measuring tool that uses the rotation axis method to measure the roundness error of a workpiece. The roundness tester is divided into sensor rotary and workbench rotary. During measurement, the measured part is installed concentric with the precision shaft system, and the precision shaft is equipped with an inductive length sensor or workbench for precise circular motion. The roundness meter consists of an instrument's sensor, amplifier, filter, and output device. If the instrument is equipped with a computer, the computer is also included in this system.
A roundness tester is a precision instrument used to measure the out-of-roundness of a rotating surface (shaft, hole, or spherical surface) of a component. There are usually two types: small desktop, where the workpiece is mounted on a rotating workbench and the measuring head is mounted on a fixed column; and Large floor mounted, with the workpiece installed on a fixed workbench and the measuring head installed on the rotating spindle. During measurement, the measuring head contacts the workpiece's surface, and the instrument's rotating part (workbench or spindle) rotates for one cycle. Due to the extremely high accuracy of the supporting bearings in the rotating part, the measuring head will generate a high-precision circular trajectory on the measured surface during rotation. The out-of-roundness of the measured surface causes the measuring head to shift and transform into an electrical (or pneumatic) signal. After amplification, it can be automatically recorded on a circular recording paper, and the out-of-roundness of each part can be directly read out for accuracy evaluation and process analysis and widely used in precision bearings, machine tools, and instrument manufacturing industries.
The Roundness Testeradopts a radius measurement method and operates in a rotating manner. The rotation axis system of the roundness meter adopts a high-precision air floating spindle as the measurement reference; The electrical part of the roundness tester is composed of advanced computers, precision circular grating sensors, and precision inductance displacement sensors. The circular grating sensors and precision inductance displacement sensors measure angle and radial displacement, ensuring the accuracy of measuring the angular displacement and radial value of the workpiece; The roundness meter measurement software adopts a roundness measurement software based on the Chinese version of WinXP operating system platform, completing data collection, processing, and measurement data management.
China Roundness Measuring Instrument,Roundness Tester Machine,Mitutoyo Roundness Tester Manufacturer
Zhejiang dexun instrument technology co., ltd , https://www.dexunmeasuring.com