1. Applying manure with low or no ripening, the bacteria and eggs are abundant, and the problem of ammonia damage occurs.
2. The large amount of chicken manure applied in a row causes severe over-limitation of phosphate fertilizer, exacerbates soil acidification and salinization, and aggravates the lack of zinc, iron and calcium ions. Phosphorus hinders the absorption, transportation and utilization of zinc, reduces the activity of iron, and affects the role of calcium in plants. In the first year, the amount of chicken manure should be 8-12 square meters. In the second year and later, the amount of acre should be 3-5 square meters. The insufficient organic fertilizer can be supplemented with other organic fertilizers such as pig manure and cow dung.
3, the phenomenon that the greenhouse does not need crop straw organic fertilizer is very common. In fact, straw is an essential and difficult to replace organic fertilizer for greenhouse cultivation. It not only provides a large amount of potassium and abundant organic matter, but also mainly supplements greenhouse carbon dioxide, adjusts carbon and nitrogen ratio, improves soil aggregate structure, increases soil beneficial microbial community, improves soil micro-ecological balance, and alleviates salt damage caused by improper fertilization. . The straw fertilizer applied in the greenhouse may be a non-fertilized straw that is chopped to a length of about 5 cm. It is poured into the tillage layer one month before the planting, and slowly maturized after watering, and the amount of the mu is 1000-1500 kg. It is better to use straw, cornstalks and wheat straw.
Huaxian County Fertilizer Station Yue Xiuli
Metallographic Microscope Series
The structure of optical metallographic microscope generally includes magnification system, optical path system and mechanical system, among which the magnification system is the key part. The preparation process of metallographic samples generally includes five steps: sampling, rough grinding, fine grinding, polishing and etching. The interception of samples from metallic materials and parts to be tested is called "sampling". Selection of sampling sites and grinding surfaces must be based on analysis requirements. The size of the sample is not uniform, from the perspective of easy to hold and grinding, the general diameter or side length of 15~20mm, 12~18mm high is suitable. For those too small, irregular shape and the need to protect the edge of the sample, you can adopt Mosaic or mechanical clamping method. For the inlay of metallographic sample, the appropriate size (about φ L5-20mm) of steel tube, plastic tube or paper shell tube is placed on the smooth plastic (or glass) plate, and the sample is placed in the tube to be ground face downwards into the filler, which can be solidified and hardened for a period of time. 3) Chamfering On the premise of not affecting the purpose of observation, the edges and corners on the sample should be ground off to avoid scratching the sandpaper and polishing fabric.
metallurgical analysis,optical microscope for metallurgy,metallurgy microscope
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