The properties and identification methods of several common fertilizers
1, urea
The appearance of urea is white, spherical particles, total nitrogen content ≥ 46.0%, easy to absorb moisture, and hygroscopicity is between ammonium sulfate and ammonium nitrate. Urea is easily soluble in water and liquid ammonia. When pure urea is heated to near the melting point under normal pressure, it begins to show instability, produces a condensation reaction, and produces biuret, which loses fertilizer effect on the crop. If you put a clean piece of iron on the stove and put the urea granules on it, it can be seen that the urea melts and volatilizes quickly, and a small amount of white smoke is emitted, which can smell ammonia.
2, ammonium sulfate
The ammonium sulfate for agriculture is white or light-colored crystals, and the nitrogen content is ≥ 20.8% (second grade). Ammonium sulfate is easy to absorb moisture, soluble in water, and the aqueous solution is acidic. It reacts with alkali to release ammonia gas. When ammonium sulfate is heated on the fire, it can be slowly melted and accompanied by ammonia release.
3. Ammonium nitrate
Ammonium nitrate has a white appearance and no visible impurities, and agricultural products are allowed to have a yellowish color. The total nitrogen content is ≥34.4% (Level II). Ammonium nitrate has strong hygroscopicity and agglomeration. When the temperature of the aqueous solution changes, recrystallization will occur, which is very sensitive to the action of heat. A large amount of ammonium nitrate is easily decomposed by heat, and combustion can occur, resulting in an explosion. It is accompanied by white smoke, which smells ammonia and the aqueous solution is acidic.
4, ammonium chloride
Ammonium chloride is white crystal, the agricultural product is allowed to have a yellowish color, the nitrogen content is ≥25.39%, and it is easily soluble in water. The solubility in water increases remarkably with the increase of temperature, and the aqueous solution is acidic. Ammonium chloride has strong water absorption and easy to agglomerate. A small amount of ammonium chloride is heated on the fire to smell a strong irritating odor, accompanied by white smoke. The ammonium chloride will melt rapidly and disappear completely. The unmelted portion was yellow during the process.
5. Ammonium bicarbonate for agriculture
Appearance is white or slightly gray crystal, with ammonia smell, nitrogen content ≥ 16.80% (secondary). It is highly hygroscopic, soluble in water, and the aqueous solution is weakly acidic. When you easily identify ammonium bicarbonate, you can use a finger to take a small amount of sample for rubbing, you can smell a strong ammonia smell.
6, superphosphate
The appearance is dark gray, grayish white, light yellow and other loose powder, and there are many small pores in the block, commonly known as "honeycomb eye". The effective phosphorus pentoxide content is ≥12.0% (qualified product II). Slightly sour, it is an acidic chemical fertilizer that is sensitive to the action of alkali and easily loses its fertilizer effect. Some of them are soluble in water and the aqueous solution is acidic. Under normal circumstances, the hygroscopicity is small, such as moisture absorption when the air humidity reaches 80% or more, forming a hard block. It is unstable when heated, and it can be seen to be slightly smoked and has a sour taste. When the temperature is higher than 120 °C, the calcium dihydrogen phosphate monohydrate loses the crystal water and turns into anhydrous calcium dihydrogen phosphate, and the water-soluble phosphorus pentoxide gradually decreases. When the temperature is higher than 150 °C, the anhydrous calcium dihydrogen phosphate loses water and is converted into calcium pyrophosphate which has no fertilizer effect on the crop. The temperature is higher, and the calcium pyrophosphate is converted into the bismuth-soluble calcium metaphosphate.
7. Calcium magnesium phosphate fertilizer
Appearance is grayish white, grayish green or grayish black powder, which looks very fine. Under the illumination of sunlight, it is generally seen that pulverized, vitreous-like objects exist and sparkle. Effective phosphorus pentoxide content ≥ 12.0% (qualified product). Insoluble in water, not easy to lose, no moisture absorption, no toxicity, no corrosive, no change when heating on fire.
8. Compound fertilizer
The appearance should be a taupe or off-white granular product with no visible mechanical impurities present. Some of the compound fertilizers are accompanied by crystallization of white particles of incompletely pulverized urea, or in the compound fertilizer, urea is present as a single crystal. The total nutrient of low-concentration compound fertilizer is ≥25%; the total nutrient of medium-concentration compound fertilizer is ≥30%, and the total nutrient of high-concentration compound fertilizer is ≥40%, of which the single nutrient content should not be lower than 4%. The compound fertilizer is slightly hygroscopic. After the moisture absorption, the compound fertilizer particles are easily pulverized, non-toxic, odorless, non-corrosive, and only partially soluble in water. When the compound fertilizer is heated on the flame, white smoke is observed, and the smell of ammonia can be smelled, and it cannot be completely melted.
9. Zinc sulfate for agriculture
Appearance is white or micro-colored needle crystals. The zinc content of zinc sulfate heptahydrate should be ≥21.8%. Zinc sulfate is readily soluble in water and its aqueous solution is acidic.
10. Potassium dihydrogen phosphate
The appearance is white crystal. The content of potassium dihydrogen phosphate for agriculture should be ≥92.0% (on a dry basis). Potassium dihydrogen phosphate is easily soluble in water and the aqueous solution is acidic.
2 correct identification of true and false fertilizer methods
Packaging identification
1. Inspection mark: The relevant state department stipulates that the product name, nutrient content, grade, trademark, net weight, standard code, factory name, factory address and production license number mark must be indicated on the fertilizer packaging bag. If the above logo or logo is not complete, it may be a fake or inferior fertilizer. 2, check the sealing of the packaging bag: special attention should be paid to the chemical fertilizer with obvious unsealing marks on the packaging seal. This phenomenon may be adulterated.
Shape, color identification
Urea: white or light yellow, in the form of granules, needles or prismatic crystals, no powder or little powder. Ammonium sulfate: white crystals. Ammonium chloride: white or light yellow crystals. Ammonium bicarbonate: white or other dyed powder or granular crystals. There are also some manufacturers that produce large particles of spheroidal ammonium bicarbonate. Superphosphate: an off-white or light gray powder. Heavy superphosphate: dark gray, off-white particles or powder. Potassium sulfate: white crystal or powder. Potassium chloride: white or light red particles.
Odour identification
If the liquid with strong pungent ammonia smell is ammonia water; the particles with obvious pungent ammonia smell are ammonium bicarbonate; the sour fine powder is heavy superphosphate. If the superphosphate has a very pungent sour taste, it is likely that spent sulfuric acid is used in the production process. This kind of chemical fertilizer is very toxic, and it is very easy to damage or burn crops, especially rice ponds cannot be used.
Need to be reminded that some fertilizers are true, but the content is very low, such as inferior superphosphate, the effective phosphorus content is less than 8% (the minimum standard should be 12%). These fertilizers are inferior fertilizers, and the fertilizer efficiency is not great. Professionals should be identified when purchasing.
3 Simple identification of pesticide failure
(1) Identification method of dairy pesticides
1. Observation method: It is found that there is sedimentation and stratification and flocculation in the pesticide. The bottle can be placed in hot water and allowed to stand for 1 hour. If the sediment is decomposed, the flocculent disappears, indicating that the pesticide is effective. Otherwise, it can no longer be use.
2, shaking method: stratification phenomenon in the pesticide bottle, the upper layer of oil floating under the layer, can shake the bottle, force the pesticide evenly, let stand for 1 hour, if it is still stratified, prove that the pesticide deterioration, such as stratification disappear, explain It has not expired and can be used.
(2) Powder pesticide identification method
1. Suspension method: Take 50 grams of powder pesticide, put it in a glass bottle, add a little water to make a paste, add a proper amount of water and mix well, place it for 10-20 minutes. The good pesticide powder is fine, less and the precipitation is slow. The pesticide particles are precipitated quickly and often.
2, cauterization method: take 10-20 grams of pesticide pesticide, placed on a metal sheet placed on the fire, if white smoke, prove that the pesticide has not failed, otherwise it has been invalid, the identification of 5% carbendazim powder is usually used this method .
3. Observation method: If the powder pesticide has been agglomerated, it is not easy to be broken, and it proves to be invalid and can no longer be used.
(3) Method for identifying pesticides for wettable powders
Cancel a cup of water and gently sprinkle a little pesticide on the water. After 1 minute, if the pesticide is still not dissolved in the water, it has deteriorated. In addition, 1 gram of pesticide is sprinkled into a glass of water and stirred thoroughly. If precipitation occurs quickly, the liquid surface appears translucent, indicating that the pesticide has failed and cannot be used.
Ecological agriculture headlines
Micro signal: henanzhengdao (long press copy)
Pay attention to the headlines of ecological agriculture and learn new agricultural knowledge every day!
4 how to quickly identify the true and false of calcium phosphate
(1) Appearance recognition
Really superphosphate is a colored loose. The following marks shall be printed on the packaging bag: product name, trademark, effective phosphorus pentoxide content, net weight, implementation standard number, production license number, factory name, factory address, etc., and the printing is formal and clear.
(2) Sensory recognition
1. Take a little calcium phosphate and put it in your mouth to taste it. If it has sour taste, it means that it is really superphosphate; if it is alkaline, it means phosphogypsum.
2, take a little calcium phosphate, placed on a piece of white paper and placed in a bright place to observe, if the appearance of the powder is fine, which contains glassy fine particles, and the powder seems to be magnetic, it can be judged that superphosphate mixed Phosphogypsum, the more glass luster particles, the more phosphorous gypsum is added.
5How to identify true and false compound fertilizer
(1) Formation and color
The compound fertilizer is mostly red granules, and a few of them are white granules due to the use of white potassium chloride as a raw material. Particles of size 1--4 mm account for more than 90%. The fake compound fertilizer has poor granularity, mostly powdery, and the color is gray or black.
(2) Dissolution
The compound fertilizer has good solubility. Put a few compound fertilizers into the container, add a small amount of water and stir quickly. The particles will disappear quickly, and the faster the disappearance, the better the quality of the compound fertilizer. The counterfeit compound fertilizer has poor solubility and does not dissolve or dissolve a little after being stirred in water, leaving a large amount of insoluble residue.
(3) Burning test
Place the compound fertilizer on the charcoal-burning charcoal or the burning cigarette head. The fertilizer will melt immediately and the foam will boil, and ammonia will be released. The fake compound fertilizer does not melt or melt a very small portion.
6 five methods of knowing fake and bad metamorphic pesticides
View method
Liquid pesticides should generally be transparent and free from oil slicks, without precipitation. A drop of water is quickly emulsified into a milky liquid; the powdered pesticide should be loose and not agglomerated; the wettable powder is shaken into water and becomes an emulsion. . At the same time, it is necessary to check whether the product packaging is qualified, whether there is a product registration number, a production permit number, an anti-counterfeiting mark, whether the product is within the warranty period.
Water method
Suitable for checking emulsion pesticides. Take a little medicine during the inspection, add 1 to 2 times of water, stir and let stand for 1 hour. If there is a floating oil layer on the water surface, the pesticide is a fake pesticide.
Oscillation
Used in emulsion pesticides. If the pesticide in the vial is stratified, it can be shaken evenly. After standing for 1 hour, observe that if there is still stratification, the pesticide has deteriorated.
Suspension method
Used to check wettable powder pesticides. Take a small amount of powder in the cup during the inspection, add appropriate amount of water and stir into a paste, then add water and stir for a period of time. If there is precipitation, it is a fake pesticide.
Test method
Used to check for new pesticides. The liquid medicine can be configured according to the instructions for use, and then sprayed on the crops with existing pests and diseases. If the control effect does not meet the control requirements, it indicates that the pesticide is invalid and may be a fake and shoddy pesticide.
Ecological agriculture headlines
Micro signal: henanzhengdao (long press copy)
Pay attention to the headlines of ecological agriculture and learn new agricultural knowledge every day!
7How to identify pesticides "three certificates"
Pesticides are important agricultural materials and special commodities. The State Regulations on Pesticide Management stipulates that the state implements a pesticide registration system; the state implements a pesticide production license system; pesticide production enterprises shall produce according to pesticide product quality standards and technical regulations... Before leaving the factory, it shall pass the quality inspection and be accompanied by the product quality inspection certificate. This is the three certificates of pesticides we usually talk about, and they are indispensable. How should we identify pesticides in order to prevent counterfeit pesticides?
1. Pesticide registration certificate:
The temporary registration certificate starts with LS or WL. The official (variety) registration certificate number starts with PD, PDN or WP, WPN. The subcontracting registration number is still required for the separation of pesticides.
2. Production license number:
The pesticide production license number format is XK13?067009 (40% amphetamine emulsifiable concentrate), and the pesticide production approval document number format is HNP33055??C0440 (58% Checaobao soluble powder)
3. Quality Standard Certificate:
China's pesticide quality standards are divided into national standards, industry standards, and enterprise standards. The license numbers are based on GB or Q.
The three certificates that do not start with the above-mentioned LS, PD, XK, Q and other English letters are often written by themselves and are not protected by law. Their quality is doubtful.
8 Identification of vegetable seeds
The newness of vegetable seeds has a great impact on agricultural production. Farmers can use the methods of seeing, squeezing, biting, and taste to judge the freshness of vegetable seeds when purchasing seeds. The new seeds are generally smooth and shiny, and the nose smells the inherent taste of the plants. Chen seeds are the opposite. The specific identification method is as follows:
1, green onions, onions, leeks and other onion vegetable seeds: green onions, onions, new seeds, the epidermis is shiny, dark black, with the original variety of spicy taste, Chen seeds opposite. The seed surface of the new amaranth has wrinkles and luster, and the seed coat has white spots. The seeds of Chen are not shiny, and the outside of the seed coat is attached with "white frost", and the umbilicus changes from white to yellow.
2, cabbage, radish and other cruciferous vegetable seeds: the new seed surface is smooth, rich in fragrant smell, with the nail pressure heavy oil spills, broken seeds into a sheet, the seed coat is light yellow green or yellow-green. Chen's seed skin is dull, sometimes the skin looks like salt cream, it is crushed with nails, the oil is less, the seed coat is easy to detach, and the cotyledons are yellow.
3, spinach seeds: the new seeds are yellow-green, with a fragrant smell, the internal starch is white. The seeds of the Chen are yellowish or grayish yellow with a musty taste and the starch inside the seeds is gray.
4, carrot seeds: the new seeds are yellow-green, with a fragrant smell, white kernels. Chen seeds are yellow or dark yellow, losing the inherent aroma of carrots.
9How to identify diseased seeds
1, corn species
Scab:
The epidermis of the diseased grain is surrounded by red or pink silk, and the yellowish and red mycelium often grows when the seed germination.
Round spot disease:
The seed and the ear axis of the diseased ear are black, and the grain is black and dried. Generally, the middle or top of the ear is damaged, the diseased part is sunken, the ear is curved, and the grain is covered with black mold.
Dry rot:
The outer part of the diseased grain is brown or black, and the dry rot is reduced. It is surrounded by white mildew when germinated, and sometimes black granules are attached to the lower part of the diseased granule.
2, soybean species
Mosaic disease:
The diseased grain is brownish-colored and extends to the sides with the umbilicus as the center.
Purple spot disease:
There are lavender to dark purple spots on the seed coat.
Gray spot disease:
There are round or irregular auburn lesions on the seeds, and no mold is formed in the center.
3. Rice varieties
rice blast:
The lesions of the damaged grain are usually elliptical or irregular, brown or dark brown.
Miao Miao disease:
Some of the diseased grains become sputum granules, and some of the granules inside and outside the stalk have a layer of linear streaks, and the appearance of the diseased granules has no obvious abnormal symptoms.
This article URL: 2018 new summary of the properties and identification methods of several common fertilizers
Acrylic Foam Tape,Vhb Tape Waterproof,Adhesive Acrylic Foam Tape,Acrylic Foam Mounting Tape
Kunshan Jieyudeng Intelligent Technology Co., Ltd. , https://www.jerrytapes.com