The purchase of high-quality crab seedlings is an important guarantee for successful breeding. Practice has shown that the same quality of crab seedlings in different culture conditions, the difference is not obvious, but the real impact of the survival rate of the first phase -3 young crab is the decisive factor is the quality of crab The problem is that good seedlings are a crucial prerequisite for successful crab farming. High-quality crab seedlings have the following main characteristics, and efforts should be made to grasp:
The "three-see-one sampling" method can be used to judge the quality of crab seedlings.
1. See if the specifications are the same. The size and size of the same batch of crabs must be neat and consistent, and the general requirement is 80%-90%. Otherwise, if the high age of the rearing will be low, the period 3 to 5 of the bean crab or young crab will be more likely to result from Killing.
2. See if the body color is the same. High-quality crab seedlings have the same shades of light greenish-yellow color with a little radiance. Inferior Crab seedlings have different shades, and tender seedlings and old seedlings are uneven.
3. Look at the strength of activity. It is advisable for the crab seedlings to drain the water naturally. Do not dry it on the nylon net to avoid injury. Grab a hand, gently pinch, and then put it into the crab seedling box to see its activity. When the palm is grasped, the palm of the hand feels rough, and it is put into the crab seedling box. The crab crawls quickly and can quickly spread to the surrounding area. It is a high quality seedling. The palm of the hand does not have a rough feeling, and it is still a group when it is slowly dispersed in the seedling box. It is a poor quality seedling.
4. If possible, a sample inspection, referring to 1 to 2 grams of crab seedling counts, is converted into the number of crabs per kilogram, generally 140,000 - 16 million high-quality seedlings per kilogram of macrolarvae, 160,000 -180,000 Only medium seedlings, more than 180,000 were inferior seedlings.
5. It is recommended to use the Yangtze River No. 1 crab seed.
Audio intercom is one of the building intercom systems. It has simple functions and can meet people's daily needs. The wiring and operation are very simple and the cost is low. It is the first choice of many customers.
MK-138 audio intercom is the most popular model in our factory. The system is an intelligently programmed audio intercom system. The audio circuits are completely isolated and won`t interfere with each other. The user wire is short-circuited, which does not affect the work of the entire system.
The solution is included audio door phone, indoor unit, decoder and power supply .
An audio intercom door phone is used for each building and an indoor unit is installed in each apartment. The visitor calls the resident through audio intercom door phone, and the indoor unit rings at apartment and the resident can decide to answer .unlock or hand up .Residents can talk to the visitor. They can open the door of the building for the vistor after confirming the identity of the visitor.
Here are some parameters of this system:
1. 2-wire Nixie tube display Intercom system
2. Calling, intercom, unlocking
3. Aluminium alloy panel with physical buttons
4. Low power consumption technology solution, saving energy and long life span
5. Dimension:300*110*30(mm)
6. Install method : Wall/flush install (250*110*30mm)
7. Door opening:IC/ID card/ password/call the indoor untils unlock
Zhuhai Mingke Electronic Technology Co., Ltd. is a professional manufacturer of residential security products. It has formed a modern high-tech enterprise integrating R&D, production and sales now . The main products are video and audio intercom system, fingerprint lock, access control and smart home products.
Mingke has been committed to the cause of home security, with excellent and leading technology, and wholeheartedly provides safe security products for thousands of households; with a high sense of social responsibility, it undertakes the corporate mission of "creating a safe home for you". if you want to get our catalog,pls don`t hesitate to contact with us.
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Zhuhai Mingke Electronics Technology Co., Ltd , https://www.mingke-tech.com