There is no uniform standard for the determination of the quality of pellet feed. In addition to the general quality of feed, the quality of pellet feed is generally considered to include the following aspects: sensory index, chalking rate, hardness, water content, durability, bulk density, and so on. For fish and shrimp feeds, water stability, water resistance, sedimentation and dissolution properties are also determined.
1, sensory indicators
The size of the pellet feed should be uniform and uniform, the shape is smooth, the surface is smooth, the color is uniform, and there is no moldy deterioration and odor.
2, the determination of the rate of
The chalking rate refers to the percentage of the amount of powder produced by the pellet feed during storage and transportation and its total amount. It is required that the powdering rate of the first grade product does not exceed 9%, and the powdering rate of the second grade product does not exceed 14%.
3, the determination of the endurance index of pellet feed
Take 1kg of pellet feed, according to the diameter of the pellet, select the standard sieve, manually sift the original sample, the sieve failed to pass the sieve is the sample, take 200 g sample on the endurance index tester, to 50 The sample sieve was rotated at r/min for 10 min, the sample was taken out, sieved again with a predetermined sieve, and the sieve on the sieve was weighed.
4, the determination of the hardness of pellet feed
The hardness of pelleted feed not only affects the chalking rate and endurance index, but also affects palatability. The measurement principle is based on the magnitude of the compressive strength of the pellet feed. Commonly used grain hardness tester and SYT-20 pellet feed hardness test.
5, the determination of the stability of fish and shrimp bait in water (water resistance)
The pellet feed for fish and shrimp should have the characteristics of low solubility and suspension property. Therefore, it is required to have certain stability in water.
Weigh 10 g of pellet feed, place a 0.5 mm bowl of sieve (mesh diameter 7 cm, sieve height 3 cm), and fix it in the upper part of the glass beaker. The beaker is filled with seawater so that the liquid surface is just in the sieve hole. In the following, the beaker is placed in a water bath at 28 ° C, and a 3 mm perforated glass tube is ventilated from the bottom of the beaker near the sieve. The ventilation is 40 to 60 bubbles per minute, so that the mixture can be gently stirred continuously. As a result of the test, small particles of the collapsed feed fell from the sieve opening. After 2 hours, the residual feed on the sieve hole was taken out, baked in a 105 ° C oven to constant weight, and the compound feed without water was taken, and the same method was used to dry to constant weight, and the water content was measured. Three replicates of each sample were taken and the average value was taken. The stability of the compounded feed in water was expressed as the loss rate (%).
6, the determination of starch gelatinization degree in pellet feed
The degree of starch gelatinization refers to the percentage of the ratio of gelatinized starch to total starch in the starch. The β-amylase can quantitatively convert the starch into reducing sugar at a suitable pH and temperature for a certain period of time, and the amount of converted sugar is proportional to the degree of gelatinization of the starch. The degree of gelatinization of the starch can be calculated by measuring the amount of reducing sugar by potassium ferricyanide method.
Office illumination is a lighting scheme designed for the office environment. Good office lighting plays an important role in providing a comfortable and productive work environment.
Office lighting is generally divided into three types: task lighting, ambient lighting, and decorative lighting. Task lighting is the provision of direct light to meet the needs of the job, such as a table lamp or recessed fixture used to provide clear and bright light to reduce eye fatigue. Ambient lighting illuminates the entire office with evenly distributed soft light, providing indoor comfort and visual balance. In addition, decorative lighting can be used to enhance the atmosphere and beauty of the office to enhance the mood and creativity of employees.
In addition to considering lighting types, office lighting should also focus on energy efficiency and sustainability. The use of LED lighting technology can significantly reduce energy consumption and provide long life and better light quality. The dimming system and automated control system can be intelligently adjusted according to natural light and usage requirements, further improving energy efficiency.
A well-planned workplace lighting scheme can enhance employee comfort and productivity. By taking full advantage of different types of lighting, office lights can create a pleasant, healthy, and professional working environment, taking into account functionality, ambient atmosphere, and energy-saving needs.Office Illumination, Task Lighting, Ambient Lighting, Office Lights, Workplace Lighting
SHENZHEN LITEHOME OPTOELECTRONIC TECHNOLOGY CO., LTD. , https://www.szlitehomelight.com