Urine analyzer is an automated instrument for determining certain chemical components in urine. It is an important tool for automated urine inspection in medical laboratories. This instrument has the advantages of simple and fast operation. However, improper use of urine analyzers and many intermediate links and influencing factors directly affect the accuracy of automated analysis results, which will not only cause errors in experimental results, but even delay diagnosis. Therefore, operators are required to understand the principles, performance and precautions of automated instruments. And the knowledge of influencing factors and other aspects are fully understood, and the correct use of automated instruments can make the results obtained by the urine analyzer more reliable and accurate. Medical Urine Analyzer,Semi Automatic Urine Analyzer,Urine Analyzer and Strips,Accurate Urine Analyzer Jilin Sinoscience Technology Co. LTD , https://www.contoryinstruments.com
application
In the 1950s, a single dry chemical test strip method was used to measure protein and glucose in urine, and the changes in the color of the test strip were observed with the naked eye and compared with the standard plate to obtain the corresponding values. In the 1980s, due to the high development and widespread use of computer technology, automated urine analyzers also developed rapidly, gradually developing from semi-automatic to fully-automated. Urine analyzers are often divided into two categories according to the test items: â‘ 8-11 screening combined urine test strips mainly used for newly diagnosed patients and health examinations. The eight test items included protein, glucose, PH, ketone bodies, bilirubin, urobilinogen, red blood cells (occult blood) and nitrite; in addition to the above eight tests, urine leukocyte test was added to the nine test items. On the basis of 9 of the 10 urine analyzer testing items, the urine specific density test was added. 11 testing items have added vitamin C testing. â‘¡It is mainly used for the observation of the curative effect of the diagnosed diseases, such as the combination test strip of PH, protein and occult blood (red blood cells) for kidney disease; the combination test strip of PH, sugar and ketone body for diabetes; the combination of bilirubin and urobilinogen for liver disease test tape.
principle
This type of instrument is generally controlled by a microcomputer, and the color change on the test strip is measured semi-quantitatively by using a spherical integrator to receive dual-wavelength reflected light. There are several reagent pads containing various reagents on the reagent strip, each of which reacts independently with the corresponding components in the urine, and displays different colors. The depth of the color is proportional to a certain component in the urine, and there is another in the reagent strip" Compensation pad", as the urine background color, compensates for the errors caused by colored urine and instrument changes.
Put the reagent strip with urine adsorbed in the colorimetric tank of the instrument, and the various reagent pads that have produced chemical reactions on the reagent strip are illuminated by the light source, and the reflected light is received by the spherical analyzer, and the photocell of the spherical analyzer is reflected. Irradiate with dual-wavelength light (measurement light passing through the filter and a reference light), and the selection of each wavelength is determined by the detection item.
The instrument automatically calculates the reflectance according to the following formula, and then compares it with the standard curve, and automatically finds and prints the corresponding results of various components. If the content of a certain component in the urine is high, the reflected light of the corresponding reagent pad is dark, otherwise it is strong.
Reflectance fraction: R(%)=Tm.Cs/TsCm×100%
In the formula, R(%) is the reflectivity; Tm is the reflection intensity of the reagent pad to the measurement wavelength; Ts is the reflection intensity of the reagent pad to the reference wavelength; Cm is the reflection intensity of the calibration pad to the measurement defect length; Cs is the calibration pair. Reflection intensity at the reference wavelength.
Fertilizer purchase, use, storage
First, identify four advantages and disadvantages of chemical fertilizers walk the agricultural product market, a variety of agricultural fertilizer varieties. When consumers purchase chemical fertilizers, they should not neglect the identification of fertilizer quality. Here are several commonly used advantages and disadvantages of chemical fertilizer identification method as follows: Packaging identification method 1, check mark: National regulations, the fertilizer packaging bag must indicate the product name, nutrient content, grade, trademark, net weight, standard code, Factory name, site address, and production license number sign. If the above signs are not complete or incomplete, it may be fake chemical fertilizers or inferior chemical fertilizers. 2. Check the sealing of the bag: Special attention should be paid to the chemical fertilizer that has obvious sealing and sealing marks on the bag. This phenomenon may be adulterated. Shape, color identification method 1, urea: white or light yellow, granular, acicular or prismatic crystals, no powder or little powder. 2, ammonium sulfate: white crystals. 3, ammonium chloride: white or light yellow crystals. Ammonium bicarbonate: white or other colored powder or granular crystals. There are also individual manufacturers that produce large particles of spheroidal ammonium bicarbonate. 5, ammonia: a colorless or dark liquid. 6, superphosphate: gray or light gray powder. 7, heavy calcium phosphate: dark gray, gray particles or powder. 8, nitrophosphate: gray particles. 9, potassium sulfate: white crystals or powder. 10, potassium chloride: white or light red particles. 11, ammonium phosphate fertilizer: gray or dark gray granular formulations. Odor identification can also be identified by smelling. The liquid with strong pungent ammonia smell is ammonia water; the particles with obvious pungent ammonia taste are ammonium bicarbonate; the fine powder with sour taste is heavy calcium phosphate. For example, if superphosphate has a very pungent and sour taste, it means that waste sulfuric acid is likely to be used during and after production. This chemical fertilizer is very toxic and can easily damage or burn crops, especially in rice ponds. Add water to dissolve the identification method to take the required chemical fertilizer 1g, put it in a clean glass tube or glass, white porcelain bowl, add 10ml distilled water or clean cold water to shake it completely to see the dissolution: all dissolved is nitrogen fertilizer or potash fertilizer Dissolved in water but residue is superphosphate; soluble in water, without residue or residue is very small; superphosphate; dissolved in water but the ammonia smell is ammonium bicarbonate. It should be reminded that although some chemical fertilizers are true, their content is very low, such as inferior superphosphate, and the effective phosphorus content is less than 8% (the minimum standard should reach 12%). These chemical fertilizers should be inferior chemical fertilizers and have no effect on agricultural crops. Big, consumers should ask professionals for identification. Second, the purchase of chemical fertilizers learned to buy fertilizer first thing to pay attention to the name of the fertilizer. In general, the most important elements contained in fertilizers can be reflected in the name. There are two points to note here. First, if you want to buy some special fertilizers, you must look at the packaging. "Special fertilizer" is not the only word that can be used by retailers; second is that they cannot be misled by the names of certain products. Product names are not allowed to add words that are untrue and expand in nature, such as "efficient" and "fat king". "All-element fertilizer" and so on. The second aspect to pay attention to when purchasing chemical fertilizers is the cooperative type. The compound formula is a direct expression of the contents of nitrogen, phosphorus, and potassium in chemical fertilizers on the outer packaging. It is expressed in the order of N-P2O5-K2O (total nitrogen - available phosphorus pentoxide-potassium oxide) in Arabic numerals. Its way of percentage content in compound fertilizers. If the formula is "15-15-15", the content of nitrogen, phosphorus and potassium in the fertilizer is 15%. If the formula is "20-15-0", it means that the content of nitrogen in the fertilizer is 20%. The phosphorus content is 15%. The last "0" indicates that the fertilizer does not contain potassium. The third aspect to pay attention to when purchasing chemical fertilizers is whether there are any special tips on the accidental packaging. The same is potassium fertilizer. After the potassium chloride is applied to the soil, the chloride ions can easily dissolve into the soil moisture and thus be absorbed by the crop together with potassium. However, some crops are very sensitive to chlorine (such as some vegetables and fruits). After absorbing chlorine, they may cause yellow leaf and fruit setting rate to be reduced. Potassium sulphate does not cause this kind of hazard. Sulfate ions generally combine with calcium ions in the soil to form calcium sulphate precipitates, which make it impossible for crops to absorb. In this way, only potassium can enter the crop, and no fertilizer residue will be generated. . Therefore, the relevant standards stipulate that if the fertilizer contains chlorine and its content exceeds 3%, the word “chlorine-containing†must be indicated on the outer packaging. When buying chemical fertilizers, you should also pay attention to the name, address, standard code, product grade, product category, and production date. In addition to the above points, it is best not to forget to ask the seller for invoices when buying chemical fertilizers. This can be used as proof of complaints when quality problems are discovered. Third, the application of chemical fertilizers ten taboo nitrogen fertilizer shallow Shi. Because the nitrogen fertilizer is applied in the shallow layer, it is easy to decompose and volatilize nitrogen after being exposed to sunlight, among which the ammonium bicarbonate is especially volatile. Therefore, we must change the habit of surface application and take a deep-seated approach to prevent the volatilization of nitrogen. Avoid applying a chemical fertilizer alone. Single application of a fertilizer will result in the destruction of the soil aggregate structure, harden the texture, cause the soil to become acid or alkali, and seriously destroy its physical and chemical properties. Moreover, the application of a single chemical fertilizer will also affect the reproductive activities of soil beneficial microorganisms and reduce soil activity. Therefore, a rational formula fertilization should be used to achieve a mixture of inorganic and organic fertilizers. Avoid ammonia or ammonium bicarbonate in greenhouses or greenhouses. Because greenhouses or greenhouse ecological environment are in high temperature and closed environment, these two kinds of fertilizers are extremely easy to volatilize under high temperature conditions. The higher the temperature, the faster the “ammonia†volatilizes and the more volatilization amount will make ammonia smog Plants interfere with normal growth. Avoid excessive application of high-concentration fertilizer. Neither nitrogen fertilizer nor organic fertilizer should be overdosed. For example, if the urea nitrogen content is as high as 46%, if the application dose is too large and the concentration is too high, the roots of crops will appear to “suck down†and the roots will be damaged. Rotten roots died. To achieve "eat fewer meals," apply the principles of fertilization. Do not ignore the nature of fertilizers, chaos mixed with two kinds of fertilizer. For example, some “ammonia nitrogen†fertilizers should not be mixed with alkaline fertilizers such as grass ash, lime, and phosphate fertilizers. Otherwise, acid and alkali neutralization will not only accelerate nitrogen volatilization, but also result in soil compaction. Avoid excessive application of nitrogen fertilizers on leguminous crops. Legumes such as soybeans, peanuts and mung beans have rhizobia attached to their roots. If nitrogen fertilizers are applied too much, they will directly impair the nitrogen-fixing activity of rhizobia, develop "inertness" and reduce the ability to fix nitrogen. If the soil for planting leguminous crops is extremely deficient in nitrogen fertilizer, a small amount of nitrogen fertilizer can be applied in combination with phosphorus fertilizer, and balanced fertilization effects can be received. Avoid excessive use of chlorinated fertilizers for sensitive crops. Such as tobacco, oranges, potatoes, grapes and other crops, are very sensitive to chlorinated fertilizers, and avoid allocating too much chlorine fertilizer to such crops at one time. Avoid application or surface application of phosphorus fertilizer. Phosphorus has little mobility in the soil, and shallow application (sprinkling, surface application) makes phosphorus stay on the surface, cannot reach the deep layer of the soil, and cannot be absorbed by crop roots, thereby greatly reducing the fertilizer efficiency of phosphorus application. Avoid sunny afternoon at noon for foliar spray fertilizer. Because the temperature is high at noon in the summer and sunny days, if the roots are sprayed at this time, not only the fertilizers evaporate quickly, but also the fertilizer on the young branches and leaves will burn the crops, which will waste the fertilizer and hinder the normal growth of the crops. The best fertilization time should be on a hot day morning or evening. Avoid fertilization before heavy rain. Before the heavy rainfall or rainfall arrives, fertilization can easily be washed away. In particular, water-soluble urea, superphosphate and other nitrogen and phosphate fertilizers should not be used before heavy rainstorms. Fourth, how to increase the fertilizer efficiency of chemical fertilizer utilization The low utilization rate of nitrogen fertilizer is a prominent problem that hampers agricultural production. In order to reduce the loss of effective chemical fertilizer components and increase its economic efficiency, scientific and technical personnel in the agricultural and agricultural sectors have been conducting research and exploration. test. According to tests, when the temperature is 29°C and the soil moisture content is 13.6%, ammonium bicarbonate is applied to the surface, and after 12 hours volatilization loses 5.49%; while the same fertilizer is applied deeper to the soil below 6 cm, volatilization loss occurs after 12 hours. Only 0.3%. It can be seen that deep application of chemical fertilizers can increase the utilization efficiency of fertilizers. In addition, agro-logical measures that use chemical fertilizers combined with nitrogen-fixing agents or other fertilizers can significantly increase the effectiveness of fertilizer efficiency. 1. Fertilizer mixed application (1) Ammonium bicarbonate additive Chemical additive Ammonium bicarbonate additive is added to ammonium bicarbonate in proportion. It can effectively inhibit the decomposition and volatilization of nitrogen, thus improving the utilization efficiency of ammonium bicarbonate. 3- 4 times. (2) Incorporation of nitrogen-fixing agent The proportion of nitrogen-fixing agent is incorporated into the deep application of nitrogen fertilizer, the nitrogen fixation can be increased by 1.5-2.0 times, and the nitrogen utilization rate can be increased by 10%-30%. (3) Mixed application of urea and borax The application of urea and borax in the proportion of (400-500):1 can significantly reduce the volatilization loss of ammonia, increase the utilization rate of nitrogen, and can effectively prevent wheat grain from filling and canola flowering. It is not true that cotton buds do not take place. (4) Application of urea and oxalic acid in cotton application of base fertilizer, such as ammonium "nitrogen 200, phosphate 140, potash 40, oxalic acid 5" ratio, can increase the number of ammoniated bacteria 4.6 times, nitrogen utilization increased by 17.3%, nitrogen Loss rate decreased by 25%. 2. Deep application of chemical fertilizers (1) Deep application of basic fertilizer The fertilizer application device shall be installed on the plow frame. When the tractor is cultivated, the fertilizer will be applied to the tillage layer along with the ploughshare. (2) Deeply applying the seed fertilizer while sowing The fertilizer application device and the seeding device are installed in the same machine, and the fertilizer is applied deep below or below the seed while sowing. It is necessary to ensure that there is a 3-5 cm soil isolation layer between the seed fertilizers to prevent seed and fertilizer from mixing damaged seeds. (3) Apply topdressing deep in the growth process of crops use chemical fertilizer top dressing device or add topdressing device to cultivator soil cultivating machinery to complete multiple processes such as ditching, loose soil, row fertilizer and soil covering, and apply nitrogen fertilizer deep into the roots of crops. . V. “10 Preventions†for Storage and Transportation of Chemical Fertilizers Attention should be paid to the following ten points in the storage and transportation of chemical fertilizers: 1. Prevent open-air storage. Fertilizers cannot be piled up in the open air. For example, when ammonium bicarbonate is placed outdoors at an air temperature of 20°C, the ammonia loss rate is 8.8% for 1 day, 48% for 5 days, and 74% for 10 days. Therefore, the fertilizer should be placed in a cool and dry place in the house. Second, prevent moisture. Nitrate and ammonia will lose water after “drainingâ€, and the superphosphate will form a hard block and become insoluble. Therefore, chemical fertilizers are tightly packed with plastic or linoleum, and it is better to avoid contact with wet sources. Three against heat. The higher the temperature is, the more volatile and agglomerate the fertilizer becomes (the worse the stability is). Therefore, timely adjust the temperature of the storage house and keep it below 30°C. When the temperature outside the house is low, you should open the doors and windows to reduce the room temperature. Better not in the kitchen with heat. Four anti-volatilization. Ammonium carbonate is poor in stability and easily decomposes and evaporates. When the temperature is higher than 20°C, it will decompose into ammonia, carbon dioxide and water and cause loss. Therefore, it is necessary to check whether the package is damaged, how to use it, and how much to use. Five against fire. Ammonium nitrate, potassium nitrate, etc. are flammable and must not be stored together with flammable materials such as kerosene, gasoline, straw, wood chips, etc. to avoid fire. Six explosions. Ammonium nitrate, potassium nitrate, etc. are prone to explosion. If they are mixed with metal powders such as copper and iron, they can cause explosion accidents if they are rubbed. Therefore, after the hardening of these fertilizers, do not use metal objects and smash them with heavy objects. Seven anti-corrosion. Superphosphate contains free acid, which has a corrosive effect on storage equipment and human skin. It should not be stored in direct contact with the product or exposed in metal containers, nor should it be placed together with crop seeds and clothing so as not to affect the germination rate. And corrosive articles. Eight anti-mixing. Fertilizers are acidic and alkaline and should be classified and placed according to place of production, type, and nature so as not to reduce fertilizer efficiency. Nine anti poisoning. When handling poisonous and corrosive fertilizers, such as ammonium bicarbonate, there are obvious irritating odors that volatilize a toxic substance, cyanamide. It is best to wear a mask, gloves, goggles to prevent poisoning, and to wash exposed skin after handling. Ten prevent misuse. Fertilizer can not be mixed with pesticides, human and animal drugs, food items (such as sugar, salt), etc. to avoid misuse. In particular, children should be prevented from playing and eating in the storage area so as not to cause undue accidents. China Agricultural Network Editor