How to prevent the corpse from rotting

The simple and practical method is to take out the internal organs, sterilize them with absolute alcohol, then add salt to dehydrate the body quickly (in some areas, it is dehydrated by fire), and finally apply essential oil to the whole body to isolate the air and wrap it with flax. But in China, only the relevant departments can legally preserve the body. The following is a detailed description of animal carcasses:

Method for embedding insect specimens in plexiglass

Insect specimens similar to artificial amber were made by embedding methyl methacrylate (common name plexiglass). Its advantages are no fear of moth, no enzyme production and no damage. Because of its transparency and easy observation, it is especially suitable for exhibitions and teaching materials.

Materials and tools:

The raw materials for making plexiglass embedding are raw and cooked monomers bought from chemical raw materials stores. (1) raw material monomer is unpolymerized methyl methacrylate, which is a colorless and transparent liquid and acts as a solvent when embedding samples. (2) The mature monomer is polymerized methyl methacrylate, which is a colorless transparent viscous liquid. It can only maintain its original properties at a low temperature of 5 degrees Celsius, and it will polymerize and harden at a high temperature. Therefore, raw and cooked monomers should be stored in large glass stoppers and kept in the refrigerator. In order to facilitate the use and avoid improper disposal of waste materials, some monomers can be poured into two small 50 ml wide-mouth bottles for use.

Preparing insect specimens for embedding:

It is best to choose the adults of COLEOPTERA, ORTHOPTERA, Hemiptera, HYMENOPTERA and LEPIDOPTERA with complete limbs, bright colors and hard skin. Viscera of larger insects and larvae of various insects can also be used for embedding, but the required procedure is complicated due to the high water content. No matter what kind of insects are embedded, it is necessary to comb and clean in advance to improve the clarity and aesthetics.

Molding:

The utensils are glass plate (bottom) and glass slide (edge). The manufacture of the mold depends on the external shape of plexiglass embedded in the specimen: square, rectangle and diamond (if it is made into a circle, flat glass dishes with different sizes and good quality can also be used as the mold). After the mold shape is determined, the required glass mold should be scrubbed and checked repeatedly. If the surface has scars or fuzz, it can't be used, so as to avoid difficulty in demoulding or uneven surface of specimen buried block. When making a mold, first put a square piece of paper under the glass plate, so as to enclose a satisfactory shape with a glass slide. Then dip a little boiled monomer on the seam of the glass slide with tweezers to make it flow down the outside of the seam to bond the seam. This bonding method needs to be carried out twice. Then put it in an incubator at 40 degrees Celsius for about half an hour to make the mature monomer polymerize and harden.

After the mold is completed, 4-5 mm of cooked monomer can be injected (not too thick to prevent the adhesive part at the joint from dissolving, and if there are bubbles, puncture them with a scalpel). Put it in a warm fragrance at 40 degrees Celsius for 12 hours to polymerize and harden it into a fixed layer. In case of multiple injections, the thickness of hardened monomer should be not less than 3mm. In order to mark the name of the embedded insect, before the second injection of the cooked monomer, the label soaked in the raw monomer and clearly written with drawing ink is put into and dissolved in the cooked monomer. The posture to be placed depends on the situation.

Embedding:

Firstly, the dried insect specimen is soaked in the raw material monomer for about one hour, so that the insect body is completely soaked. At this time, the mature monomer is injected into the pre-made mold, but this time the amount should not exceed half of the thickness of the worm, so as to avoid the worm drifting position after placing the specimen. Then take out the specimen from the raw monomer, make the back of the worm face down, and put it on the cooked monomer in the mold. Adjust the position of the specimen with tweezers or dissecting needle. When it is stable, move it to a box with a glass cover to avoid dust for future observation. Although this polymerization takes a long time, it is not easy to produce bubbles. Two days later, probe with a scalpel. When the cooked monomer has been polymerized into semi-solid and not completely hardened, 5 mm of cooked monomer can be added. After that, every 1-2 days, before adding the cooked monomer, check as above. But in the future, it is best to inject from one end of the mold to avoid irregular injection squeezing each other to produce gas that is not easy to exhaust.

Molding and shaping:

After demoulding, it can be trimmed with scissors, steel hammer and grindstone, especially the final polymerized part. Some parts will lose luster after completion, and can be polished with a cloth wheel polishing machine.