Double-Convex Lens, also named Bi-Convex Lens,composing of two convex surfaces, has a positive focal length. DCX Lens is most suitable where the object and image are on opposite sides of the lens and the ratio of the image and object (conjugate ratio) distances is between 0.2 to 5. It is used in beam expanders,projection optics systems, optical viewers applications etc.
We also supply kinds of plano-convex spherical lenses,plano-concave spherical lenses,bi-convex spherical lenses,bi-concave spherical lenses,meniscus spherical lenses,special spherical lenses,achromatic spherical lenses,ball lenses,sphere lenses etc..
Specification of our Spherical Lens as follow:
Custom Wide Variety of Diameters and Focal Lengths. Double-Convex Spherical Lens,Double-Convex Lenses,Double-Convex Ar Coated Spheric Lenses,Double-Convex Spheric Lens China Star Optics Technology Co.,Ltd. , https://www.realpoooptics.com
(1) Flat type: Suitable for areas with high temperature, heavy rainfall, high humidity, high groundwater level or summer compost. Before the pile, the site is selected to be dry and flat, close to the water source, and convenient to transport. The stack is 2 meters wide and the stack height is 1.5-2 meters. The stack length depends on the amount of material. Prior to stacking, tamping the ground and applying a layer of fine grass or charcoal to absorb the oozing juice. Each layer is 15-24 cm thick, and each layer is filled with water, lime, sludge, human excrement, etc. The top of the pile is covered with a layer of fine soil or river mud to reduce the evaporation of water and the loss of ammonia volatilization. Stack for about 1 month, turn it over once, then add water according to the dryness and wetness of the compost, and then stack it for about 1 month, then turn it over until it is ripe. The speed of composting varies with the seasons. It is hot and humid in summer, composting is about 2 months, and it takes 3-4 months to be decomposed in winter.
(2) Half pit type: Half pit type compost is commonly used in early spring and winter in the north. First, choose to build a pit in the high stagnation of the sun. The depth of the pit is 2-3 feet, the bottom of the pit is 5-6 feet wide and 8-12 feet long. The bottom of the pit has a well-shaped ventilation groove with a groove depth of 5-6 inches. A ventilation tower is formed at the intersection of the ventilation grooves. The compost is 3 feet above the ground, and 1000 kg of air-dried straw is added. The top of the pile is sealed with mud. After the heap, the temperature rises after one week. After the high temperature period, the temperature inside the reactor drops for 5-7 days. It can be turned over, so that the inside and outside of the heap are evenly distributed, and then stacked until it is decomposed.
(3) Deep pit type: The pit depth is 2 meters, all of which are piled underground, also called “underground typeâ€. The stacking method is similar to the half pit type.
2. High temperature composting
High temperature composting is a major method for the organic fertilizer, especially the harmless treatment of human excrement. After the high temperature treatment of straw and feces, it can eliminate the harmful substances such as germs, eggs and grass. In order to speed up the decomposition of straw, high-temperature composting must be inoculated with high-temperature cellulose-decomposing bacteria, and a ventilation device should be set up. In cold regions, cold-proof measures should also be taken. There are two types of high temperature composting in the form of flat and half pit. The method of stacking is the same as that of common compost, but it is necessary to add hot high-temperature cellulose-decomposing bacteria to promote the decomposition of straw. Commonly used horse manure culture liquid instead of horse manure to achieve the purpose of inoculation. The horse manure culture solution is prepared by mixing 2 horses and manure with 20-30 kg of water and putting them into a white iron bucket. The bucket is capped and placed on top of the compost. The barrel is sold into the pile, and the barrel is exposed to the outside. It can be applied for 4-5 days at 65 °C. The amount of the culture solution is 1% of the compost material.
High temperature compost generally passes through several stages such as heat generation, high temperature, temperature drop and decompression. In the high temperature stage, it can be sterilized by insecticide.
Source: Henan Science and Technology News
*Material: BK7,fused silica,MgF2,BaF2,CaF2,ZnSe,ZnS,Ge or other optical crystals
*Dimension Tolerance +0.0 -- -0.1mm
*Center Thickness +/-0.1mm
*Focal Length Tolerance+/-1%
*Surface Quality:60/40
*Surface Figure: lambda/2 at 633nm on plano side
*Clear Aperture >90%
*Chamfer 0.25mm at 45 degree typical
*Coating : AR coating options available :MgF2, VIS 0°, VIS-NIR, NIR I, and NIR II
1. Ordinary compost: Ordinary compost is cooked under anaerobic conditions. The temperature of compost does not exceed 50 °C, and the time of decomposing is longer, about 3-5 months. The stacking method varies depending on the season and the like, and there are three types of flat type, half pit type and underground type.
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