805 results about "Chlorosulfonic acid" patented technology

The present invention provides a preparation method of lithium bis(fluorosulfonyl)amide. The method comprises the following steps: A) reacting chlorosulfuric acid with ammonia in the presence of an organic base to obtain organic alkali salt of bis(fluorosulfonyl)amide; B) mixing the bis(fluorosulfonyl)amide obtained in the step A) with HF for a fluorinated reaction to obtain an organic alkali salt of bis(fluorosulfonyl)amide; C) mixing the organic alkali salt of bis(fluorosulfonyl)amide obtained in the step B) with an alkaline substance for a neutralization reaction to obtain a bis(fluorosulfonyl)amid metal salt crude product; D) purifying the bis(fluorosulfonyl)amid metal salt crude product obtained in the step C) to obtain bis(fluorosulfonyl)amid metal salt; and E) mixing the bis(fluorosulfonyl)amid metal salt obtained in the step D) with a lithium reagent for a replacement reaction, so as to obtain lithium bis(fluorosulfonyl)amide. The preparation method provided by the invention has the characteristics of low raw material cost, low impurity content in the product and high yield of lithium bis(fluorosulfonyl)amide.

The invention provides a method for preparing strong acidic ion-exchange fibers. The method comprises the steps of performing vacuum packaging for polyolefine fibers; pre-irradiating through a radiation source; feeding pre-irradiated polyolefine fibers into a grafting solution under the protection of inert gas to react to obtain a polyolefine fiber grafting copolymer; then sulphonating through chlorosulfonic acid to obtain strong acidic ion-exchange fibers; a cross-linking agent is fed into the grafting solution to enable high mechanical strength and relatively high exchange capacity of the sulphonated fibers. According to the method, the process is simple, the polyolefine fiber grafting copolymer is easily prepared under a low temperature condition; the prepared polyolefine fiber-styrene copolymer is low in styrene autopolymer (less than 2%); the dichloroethane solution of chlorosulfonic acid is treated as a sulphonating agent, so that little chlorosulfonic acid is used, and the post-processing is simple.

The invention relates to the field of chemical synthesizing, in particular to a preparation method of imidodisulfuryl fluoride lithium salt. The preparation method includes the steps of firstly, allowing chlorosulfonic acid and chlorosulfonyl isocyanate to react in the presence of catalyst to obtain dichlorosulfimide; secondly, allowing dichlorosulfimide and hydrogen fluoride to react in the presence of catalyst to obtain imidodisulfuryl fluoride; thirdly, allowing imidodisulfuryl fluoride to react with compound containing lithium to obtain the imidodisulfuryl fluoride lithium salt. The preparation method has the advantages that the chlorosulfonic acid and chlorosulfonyl isocyanate are used as the raw materials in the first-step reaction, the generation of waste gases such as SO2 and HCl is avoided, and environment protection requirements are satisfied.

The invention discloses a method for preparing sulfonated polymer films, which comprises the following steps: preparing a casting solution and film-forming on the basis of phase-inversion. The sulfonation reaction is carried out between one or two of polyether-ether-ketone (PEEK), phenolphthalein polyaryl ether sulfone (PES-C) or polystyrene (PS) and concentrated sulfuric acid, fuming sulfuric acid or chlorosulfonic acid to obtain a sulfonated polymer solution in the preparation of the casting solution; and then, the film is directly formed on the basis of the phase-inversion method. The sulfonated polymer film prepared by the invention has higher pure water flux and protein retention rate, furthermore, the method has the advantages of good anti-pollution performance, higher mechanical strength and simple preparation process.

The invention provides a composition of a surfactant oil displacement system for anionic and nonionic oil displacement. The composition consists of 18% C18 sodium alkyl benzene sulfonate, C16 fatty acid, 25% C2 alkanolamide, 7% C8 alkylphenol polyoxyethylene ether phosphate, 17% ethanol, 3% octanol, 30% water; the alkyl is a hydrocarbyl group with linear chain, branched chain and ring structures in a calibrated carbon atom range, and also can be substituted by one or more halogens, alkyls or alkoxys; the sodium sulfonates are formed by sulfonating different alkanes or arenes by SO3 or chlorosulfonic acid in chloroalkane environment and then neutralizing the sulfonate and sodium hydroxide; and the esterification derivatives are sulfates or phosphates. The formulation has highoil displacement efficiency, strong oil deposit adaptability and good popularization prospect.

This invention relates to a method for separating and purifying mixing exhaust gas of chlorine and hydrochloride, comprising: absorb the chlorine in the mixing exhaust gas using solvent A to separate from gas phase hydrochloride, the chlorine can be obtained after solvent A desorption, the hydrochloride can be obtained by removing solvent A in the gas phage hydrochloride using solvent B, wherein: solvent A is one of benzene, silicon tetrachloride, nonyl hydride, sulfur monochloride, carbon tetrachloride and chlorosulfonic acid, and solvent B is one of cyclopentadiene and hexachlorobutadiene. By washing with concentrated hydrochloric acid to remove trace amount of organic compounds, and chemical washing to remove heavy metal elements, the hydrochloride is absorbed by water to make hydrochloric acid. This invention is characterized of efficient separation of chlorine and hydrochloride, high efficiency of separation, low cost, high-usage of resources, high purity of chlorine up to 99%, recycling use, and the purity of hydrochloride meets the requirement of producing industrial hydrochloride and hydrochloride regent .

A process for producing a bis(fluorosulfonyl)imide anion compound by substituting a bis(chlorosulfonyl)imide anion compound, obtained from sulfamic acid, chlorosulfonic acid, and a halogenating agent, with fluorine is used as a process for producing a fluorine compound for use, for example, in the synthesis of battery electrolytes and ionic liquids. According to the above process, the inclusion of impurities can be reduced, and a high-purity fluorine compound of a bis(fluorosulfonyl)imide compound can be efficiently produced at a high yield. A base catalyst can be used in the reaction for substituting the bis(chlorosulfonyl)imide anion with fluorine. The base catalyst is preferably a nitrogen-containing compound.

The invention relates to a preparation method of sulfated polysaccharide. Firstly, the polysaccharide reacts with organic silicon and then reacts with sulfuric acid esterification reagent such as sulfur trioxide-pyridine complex, chlorosulfonic acid and the like, and finally the sulfated polysaccharide is prepared. The method has the advantages of mild reaction, easy control, high yield and good repeatability. By utilizing the method, sulfated polysaccharide with wider scope of sulfated degree can be prepared, the sulfated substitution degree can be up to 2.95 at most, moreover, the polysaccharide degradation in the reaction process is less, the side effects are less, the product color is light, and the product is especially suitable for being applied as a drug.

The invention discloses a Gemini surfactant and a preparation method thereof. The structure of the Gemini surfactant is as shown in formula (I), wherein R is a C8-C16 alkyl group, and n is a natural number ranging from 1 to 3. The preparation method of the cationic Gemini surfactant as shown in formula (I) comprises the following steps: 1) reacting C8-C16 fatty alcohol with epoxy chloropropane in the presence of a basic compound and a phase transfer catalyst to generate a compound as shown in formula (II), wherein R is as defined in formula (1); 2) reacting the compound as shown in formula (II) with polyethylene glycol in the presence of alkali metal, and acidifying to obtain a compound as shown in formula (III), wherein the polymerization degree of the polyethylene glycol is 1-3; and 3) reacting the compound as shown in formula (III) with chlorosulfonic acid, and alkalifying to obtain the Gemini surfactant as shown in formula (I). The surfactant provided by the invention has stronger temperature tolerance, salt resistance, foamability and emulsibility, and can achieve a favorable synergic effect when being used with surfactants of other types.

The invention provides a preparation method of mesotrione. The preparation method comprises is capable of preparing the target product from raw materials such as ortho-nitrotoluene, chlorosulfonic acid, sulfoxide chloride, sodium sulfite, chloroactic acid, 1,3-cyclohexanedione in the presence of a catalyst and acid-base. The preparation method is based on common chemical raw materials, the reaction flow of each step is implemented under conventional operation conditions, the amount of three wastes is low, the total yield is above 61%, the purity of the product is high, the purity of the coarse product of the mesotrione is greater than 98%, and the coarse product of the mesotrione can be further purified; as a result, the preparation method of mesotrione is applicable to large-scale industrial production.

The invention discloses a method for preparing a homogeneous phase ion exchange membrane. The method comprises the following steps: (1) blending a functional monomer, a cross-linking agent and an initiator into a uniform solution, thereby obtaining a membrane liquid; (2) soaking a substrate into the membrane liquid to impregnate, taking out the substrate, and clamping between two thin clamps, thereby forming a composite body; (3) enabling the initiator to initialize polymerization reaction on the composite body at 60-120 DEG C, and peeling off the two thin clamps, thereby obtaining a polymerized membrane; (4) putting the polymerized membrane into a chlorosulfonic acid chloroform solution for sulfonation treatment, after the sulfonation treatment, soaking in a NaCl solution, after being soaked, washing with water, and drying, thereby obtaining a Na type cation exchange membrane, or putting the polymerized membrane into a trimethylamine solution, performing amination treatment at 20-40 DEG C, after the amination treatment, soaking in the NaCl solution, after being soaked, washing with water, and drying, thereby obtaining a Cl type anion exchange membrane. The cation exchange membrane prepared by using the method is low in surface resistance, high in transference number and relatively high in selectivity.

The invention discloses a method for preparing bis(sulfonyl fluoride) imine and (perfluoroalkyl sulfonyl fluorine sulfonyl) imine alkali metal salt. According to the method, sulfamide is utilized to take reaction with thionyl chloride and chlorosulfonic acid for preparing bis(sulfonyl fluoride) imine or (perfluoroalkyl sulfonyl fluorine sulfonyl) imine, then, the bis(sulfonyl fluoride) imine or (perfluoroalkyl sulfonyl fluorine sulfonyl) imine takes reaction with antimony trifluoride and potassium (rubidium or caesium and the like) carbonate, and corresponding high-purity bis(sulfonyl fluoride) imine potassium (rubidium or caesium) salt or (perfluoroalkyl sulfonyl fluorine sulfonyl) imine potassium (rubidium or caesium) salt can be obtained; and the double decomposition exchange reaction of the potassium (rubidium or caesium) salt and lithium (or sodium) perchlorate or lithium (or sodium) tetrafluoroborate and the like in aprotic polar solvents is utilized to obtain corresponding high-purity lithium (or sodium) salt. The method provided by the invention has the characteristics that the operation step is simple, the products can be easily separated and purified, the purity and the yield are high, the environment pollution is avoided, the method is suitable for industrial mass production, and the like.

Process for the preparation of O-sulfated K4, K5 and K40 polysaccharides useful for the treatment of tumoral, HIV-1 and coagulation pathologies and in cosmetic preparations, wherein the K4, K5 or K40 polysaccharide in the form of sodium salt is suspended in an aprotic solvent and directly submitted to the reaction of O-sulfation with a pyridine-sulphur trioxide or trimetylamine-sulphur trioxide adduct or with chlorosulfonic acid.

The invention relates to an alkylbenzene sulfonate Gemini surfactant and a preparation method thereof. The method comprises the following steps of: undergoing a substitution reaction: undergoing a substitutive etherification reaction at the temperature of 65-70 DEG C for 6 hours on phenol and dihalogenated alkane under the action of a phase transfer catalyst to generate bisether, wherein the molar ratio of the phenol to saturated dihalide is 1:3, the saturated dihalide is head-to-end dibromoalkane, the quantity of atoms C of the dibromoalkane is larger than 2, and the phase transfer catalyst is tetrabutylammonium bromide; performing Fourier alkylation: making the bis-ether react with an alkyl halide at the temperature of 80 DEG C and under the pressure of 0.3 MPa under the action of a Louis acid catalyst to generate dialkyl phenylate, wherein the molar ratio of the bis-ether to the alkyl halide is 1:2; undergoing a sulfonation reaction: undergoing a sulfonation reaction on the dialkyl phenylate and a chlorosulfonic acid in the molar ratio of 1:4 by taking dichloromethane as a solvent at the temperature of 0 DEG C; and undergoing a salt-forming reaction: adding an alkali to generate a target product. The alkylbenzene sulfonate Gemini surfactant has very high interfacial activity and a very low critical micelle concentration.

The invention relates to a fasudil hydrochloride compound and a novel method thereof. The method comprises the following steps of: in the presence of a solvent, performing sulfonation reaction on a chlorosulfonic acid serving as a sulfonating agent and isoquinoline to generate a 5-isoquinolinesulfonic acid; reacting the 5-isoquinolinesulfonic acid with thionyl chloride under a heating condition to generate isoquinoline-5-sulfonyl chloride hydrochloride; and dissolving the isoquinoline-5-sulfonyl chloride hydrochloride with ice water, adjusting the pH value of the solution with sodium bicarbonate, reacting the solution with homopiperazine, adjusting the pH value again with a hydrochloric acid, and concentrating under reduced pressure and recrystallizing to prepare the fasudil hydrochloride compound. The synthesis method of the invention has the advantages of mild reaction conditions, high yield and easy industrial production.

A dual-component surfactant of biether biphenylsulfonate is 2.2-bis (4-alkoxy-3- sodium phenylsulfonate) propane. Its preparing process includes such steps as adding biphenol A and the aqueous solution of NaOH into reactor, reaction at 50-78 deg.C, sequentially adding absolute alcohol and long-chain alkyl bromine into reactor, reacting at 50-78 deg.C for 12-36 hr, evaporating alcohol, washing the resultant, recrystallizing, drying to obtain biether compound, adding it into reactor, using dichloromethane as solvent, dripping chlorosulfonic acid, reaction at 15-35 deg.C for 1-3 hr, neutralizing resultant, salting out, filtering and drying. Its advantages are high surface activity, and high foam stability.

The invention discloses a method for preparing sulfated bagasse xylan. The method comprises the following steps of: dehydrating and cooling pyridine; dripping chlorosulfonic acid into the pyridine, wherein the volume ratio of the pyridine to the chlorosulfonic acid is between 15 and 25; when white solid appears in the reaction flask, adding anhydrous formamide to help dissolving, and continuing stirring for 1 to 2 hours; transferring the obtained solution into a constant-temperature water bath kettle, adding amino-sulfonic acid and bagasse xylan into the water bath kettle, and esterifying for 2.5 to 4 hours, wherein the ratio of the volume of the chlorosulfonic acid to the mass of the xylan is 1.2-2.0:0.7-1.5; adding excessive acetone and standing for 2 hours; pouring out the supernatant and adding the mixed solution of 75 to 90 volume percent methanol and water; depositing and then filtering; collecting the deposit and washing for multiple times; washing the deposit with the aqueous solution of ethanol at least once; washing and dehydrating with acetone; and drying in vacuum at 50 DEG C for 6 hours. The method has the characteristics of high substitution degree, high utilization rate of raw materials, easy control on synthesis process, simple post-treatment process and stable product quality; moreover, the prepared sulfated bagasse xylan has high water solubility.

The present invention provides a process for preparing 1,2-benzisoxazole-3-acetic acid, comprising the step of reacting 4-hydroxy-coumarin with hydroxyl-amine in the presence of a base. The present invention further provides a process for preparing a salt of benzisoxazole methane sulfonic acid, comprising the steps of 1) sulfonating 1,2-benzisoxazole-3-acetic acid using chlorosulfonic acid in a solvent mixture comprising methylene chloride and sodium hydroxide; and 2) isolating the salt of benzisoxazole methane sulfonic acid.

The present invention provides a production method of benzenesulfonyl chloride. It is characterized by that said invention uses benzene and chlorosulfonic acid as raw material, and makes them undergo the processes of sulfonation reaction, hydrolytic dilution, standing still and layer separation and reduced pressure distillation so as to obtain the invented product. Said invention also provides the concrete steps of every process and its concrete requirements.

The invention relates to a viscosity reducer and a preparation method thereof. The preparation method for the transition metal sulfonate complex thick oil water thermo-catalysis viscosity reducer is characterized by comprising the following steps of: 1) adding fatty acid alkyl ester and dichloroethane into a container in a molar mass ratio of 1:2.0-3.0; 2) placing the container into an ice water bath, dripping chlorosulfonic acid in a molar mass ratio of the fatty acid alkyl ester to the chlorosulfonic acid of 1:1.3-2.0, performing sulfonation reaction, and performing ageing after the sulfonation is finished to obtain an intermediate product; and 3) adding a transition metal oxide into the intermediate product in a molar mass ratio of the fatty acid alkyl ester to the transition metal oxide of 1:0.17-0.25, performing complex reaction for 1 to 2 hours, standing and demixing after the reaction is finished, and removing the water of the upper layer, wherein the paste of the lower layer is the transition metal sulfonate complex thick oil water thermo-catalysis viscosity reducer. The viscosity reducer prepared by the method has good viscosity reducing effect at the temperature of 200 DEG C, and simultaneously has the characteristics of easily obtained raw materials and simple preparation process.

The invention relates to a method for synthesizing p-acetamido benzene sulfonyl chloride by phosphorus pentachloride, relating to the preparation method for sterilization and mould inhibition midbody of sulfonamides. The invention takes acetanilide and chlorosulfonic acid as raw materials, uses phosphorus pentachloride as chlorinating agent; under the action of organic dissolvent, the raw materials are sulfonated, chloridized, separated, and washed to obtain the product. The invention has the effects of little chlorosulfonic acid usage, high product yield, few generated waste acid,, completely cycling dissolvent, recycled by-products, low manufacturing cost, being convenient to popularize and apply, and the like. The products prepared by the method can be widely applied to the preparation of the sterilization and mould inhibition of sulfonamides and industries such as coating, plastics, pesticides, etc.

The invention discloses a method for preparing expanded graphite or graphene. The method comprises the following technical processes: uniformly mixing graphite with a swelling agent, and adding a preprocessed solid mixture into a proper amount of chlorosulfonic acid so as to rapidly prepare the expanded graphite and the grapheneunder normal temperature. The method for preparing the expanded graphite does not relate to any high-temperature and high-pressure process and is environmentally friendly, the operation is safe, and the cost is low. The expanded graphite prepared by virtue of the method can reach 50-1000 times of volume expansion and can maintain the integrity of a graphite flake layer structure. The expanded graphite can be widely applied to various fields of energy storage, optoelectronic devices, solar cells, anticorrosive paints and the like. The expanded graphite can be further taken as a precursor for preparing high-quality graphene basically having no defect by virtue of mechanical stripping of the expanded graphite.

The present invention relates to one kind of sulfonated fluorene-containing polyaryl ether (ketone) and its application in preparing proton exchanging film. The sulfonated fluorine-containing polyaryl ether (ketone) may be prepared through polymerization of 9, 9-(4, 4-dihydroxyphenyl) fluorene and chloric or fluorous arone (arene) to form polyaryl ether (ketone); and the subsequent sulfonation with chlorosulfonic acid in the controlled consumption for controlled product sulfonation degree. The sulfonated fluorine-containing polyaryl ether (ketone) may be dissolved in different polar solvents before being cast to form single-component film, or be mixed with other polymer material for preparing composite film, or be mixed with heteropoly acid and other inorganic matter for preparing hetero film; and all these kinds of film have the advantages of low cost, high stability, high water absorption, small equivalent molecular weight, etc. and are expected to find use in fuel cell.

The invention relates to a preparation method of bromoamine acid, which comprises the following steps: (1) sulfonation reaction: by using 1-aminoanthraquinone as a raw material, dropwisely adding chlorosulfonic acid into an orthodichlorobenzene solvent to carry out sulfonation reaction so as to obtain the sulfonated material containing sulfonated product, wherein the weight ratio of the 1-aminoanthraquinone to the orthodichlorobenzene is 1:(5-7), and the temperature of the sulfonation reaction is 115-150 DEG C; (2) stratification by adding dilute sulfuric acid: after the sulfonation reaction reaches to the end, directly adding 55-60 wt% dilute sulfuric acid into the reaction system until the sulfonated material stratifies, wherein the upper stratum is an orthodichlorobenzene organic phase which can be used repeatedly, and the understratum is a sulfuric acid solution of 1-aminoanthraquinone-2-sulfonic acid; and (3) bromination reaction: adding water into the understratum material obtained in the step (2) until the acidity reaches to 8-10%, and directly dropwisely adding bromine to carry out bromination reaction, thereby obtaining the bromoamine acid crude product. The invention greatly lowers the energy consumption; and the quality and yield of the bromoamine acid product are obviously enhanced.

The invention discloses a method for preparing a less layer graphene sheet, which belongs to the field of preparation of graphene and is used for overcoming the technical defects existing in the conventional method including long time in a preparation process, low yield, unsuitability for large-scale production and the like. The invention provides a method for preparing a less layer graphene sheet rapidly on a large scale at high yield. The method comprises the following steps of: adding chlorosulfonic acid and hydrogen peroxide into graphite powder respectively; and centrifuging, washing with water and performing vacuum drying and secondary centrifuging to obtain the less layer graphene sheet. The method has the beneficial effect that: a foundation is laid for the future large-scale production of graphene sheets. High-yield graphene can be obtained from graphite powder successfully and rapidly by using chlorosulfonic acid and hydrogen peroxide serving as stripping reagents, the graphene consists of a single layer or less layer graphene sheet, and the graphene is not oxidized into a graphene oxide in a preparation process; and the less layer graphene sheet has the excellent properties of single dispersion, high quality and high conductivity (2.4*104 S / m).

The invention discloses a continuous sulfonating process for synthesizing p-aminophenyl-beta-hydroxyethyl sulfone sulphate. The process comprises the steps: performing reaction on chlorosulfonic acid and acetanilide which serve as raw materials; respectively atomizing chlorosulfonic acid and molten-state acetanilide and contacting with each other during feeding to perform reaction. According to the continuous sulfonating process for synthesizing p-aminophenyl-beta-hydroxyethyl sulfone sulphate, the molten-state acetanilide is used as a raw material, and the reaction on the acetanilide in an atomizing state and chlorosulfonic acid which is also in an atomizing state are carried out and the reaction temperature is easily controlled, so that the production of byproducts such as parachloroaniline is avoided, and the conversion rate of acetanilide serving as a raw material is high. The process is convenient to operate, short in production period, controllable in reaction process, less in labor demands, low in cost and easy for industrial production.

The present invention relates to a novel sulfonation of an intermediate of zonisamide. The sulfonation processes using chlorosulfonic acid as well as acetic anhydride and sulfuric acid in an organic solvent are disclosed. Crystalline forms of benzisoxazole methane sulfonic acid (BOS-H) and its salts (BOS-Na, BOS-Ca, and BOS-Ba) and their novel preparation processes are disclosed.

The invention discloses a preparation method for a composite film of chitosan / sulfonated polyethersulfone and polyethersulfone and an application thereof; the method comprises the following steps: preparing a chitosan acetic acid solution by dissolving chitosan acetic acid after deacetylation in a water solution; dissolving the polyethersulfone in a chloroform solution to prepare a polyethersulfone chloroform solution; dissolving chlorosulfonic acid in a chloroform solution to prepare into a solution, and dropwise adding the solution into the chlorosulfonic acid chloroform solution for sulfonation so as to obtain sulfonated polyethersulfone; mixing and dissolving the sulfonated polyethersulfone and the polyethersulfone in a dimethylformamide (DMF) solution to prepare a basement membrane solution, filtering, deaerating and shaving into a film to obtain a nonsymmetric basement membrane support layer in the water; and coating the chitosan solution on the basement membrane support layer to obtain the composite film through drying. The composite film has a good separating effect for separating alcohol and water. The preparation method has the advantages of simple preparation process, abundant raw materials, low cost and temperate conditions.

The production process of p-acetamido benzene sulfonyl chloride as intermediate for sulfanilamide medicine includes the following steps: chlorosulfonating acetylaminobenzene as main material with chlorosulfonic acid to produce sulfonated oil and absorbing hydrogen chloride gas to prepare hydrochloric acid; separating sulfonated oil, adding water and decomposing chlorosulfonic acid to obtain separated oil while absorbing produced hydrogen chloride gas; separating the separated oil and adding water to deposit out p-acetamido benzene sulfonyl chloride; further separating, eliminating p-acetamido benzene sulfonyl chloride mother liquid, water washing the crystal while side producing sulfuric acid; using the side produced sulfuric acid in recovering p-amido benzene sulfonic acid; and reusing crystal eliminating water in the separation. The present invention realizes the comprehensive utilization, protects environment and lowers the cost.

The invention provides a method for continuously preparing vinylene carbonate by a tubular reactor. The method includes using chlorosulfuric acid and ethylene carbonate as raw materials to be synthesized into chloroethylene carbonate in the tubular reactor under the action of initiator, rectifying the chloroethylene carbonate and subjecting the rectified chloroethylene carbonate to elimination reaction with trimethylamine in the tubular reactor with existence of organic solvent and generating the vinylene carbonate. By the method for continuously preparing vinylene carbonate by the tubular reactor, existing intermittent production methods are changed, reaction speed is greatly increased, reaction period is reduced, yield is increased and productivity can be effectively improved.