There are three types of rotary valves classified by type: butterfly valves, ball valves, and plunger valves.

1) Butterfly valve: The direction of flow is controlled by a baffle or blade rotating at a certain angle around the axis of rotation. The baffle or blade looks a bit like a but.......

The maintenance of the corn harvester is directly related to the technical status and performance of the machine and needs to be given enough attention by the farmers' friends:

First, the preparation for storage

1. Before entering the warehouse, completely remove the mu.......

Pear tree dormancy period is generally from December of the previous year to February of the second year. During this period, the pears are in a natural or forced dormant state, and most of the pests and diseases are also dormant.

I. Cultivation measures

Through winter prun.......

First, choose the right pesticide
1. Give preference to biological pesticides. Bioinsecticides and acaricides commonly used in production include: Bt, abamectin, Liuyangmycin, Huaguangmycin, anthocyanin, rotenone, matrine, veratrine, etc.; fungicides are: Jinggangmycin , kasugamycin, poly.......

One, deworming. Due to grazing, all goats will be infected with locusts. Generally, they will not attract the attention of breeders. However, the locusts in goats will consume large amounts of nutrients, resulting in long meat season without meat. Therefore, when the fall and winter season.......

Molecular distillation is a relatively new separation technology that has not been widely used in industrial production, and can solve a problem that cannot be solved by a large number of conventional distillation techniques. Molecular distillation is a special liquid-liquid separation technolo.......

Pleurotus ostreatus: Pleurotus ostreatus has many varieties, including low temperature type, medium temperature type, high temperature type and wide temperature type. The low-temperature mushrooming temperature is 2°C-22°C, the medium temperature mushrooming temperature is 8°C-24�.......

There are many reasons for the falling of the peppers, both physical and pathological.

Pepper likes air drying and soil moist environment, such as high temperatures (more than 35 degrees), that affect pollination, fertilization, but also easily lead to plant leggy, weakening the as.......

Although these additives do not contain the nutrients needed by chickens, they have great benefits in promoting the growth and development of chickens, increasing the egg production rate, and enhancing disease resistance and feed storage. Its types include antibiotic additives, insect repe.......

One of the conditions for use of high and low temperature low pressure test chamber : environmental conditions a, temperature: 15 ° C ~ 35 ° C;

b, relative humidity: no more than 85%;

c, atmospheric pressure: 80kPa ~ 106kPa .......