42 results about "Methanethiol" patented technology

The invention discloses a lactobacillus brevis SMF L6 strain for improving the characteristic flavor of fermented fish and application thereof, and belongs to the technical field of aquatic product processing. According to the method disclosed by the invention, low-temperature fermentation is carried out by utilizing a sake lactobacillus wide cloth SMF L6 direct vat set fermentation inoculant to regulate and control the flavor; the method can effectively promote the production of flavor substances such as n-hexyl alcohol, eudesmol, 2-ethylhexyl alcohol, 4-platycladi alcohol, linalool, 4-terpene alcohol, alpha-terpilenol, piperonone, beta-myrcene, alpha-terpinene, D-limonene, beta-phellandrene, gamma-terpinene and the like in the fermented fish. The content of pungent smell and fishy smell substances such as acetic acid, p-xylene, o-xylene, trimethylamine, methyl mercaptan and carbon disulfide is reduced.

The technology described herein is directed to compositions and methods for reducing levels of methionine. In various aspects described herein are: engineered methionine-reducing probiotic microorganisms; engineered methanethiol-reducing probiotic microorganisms; and engineered taurine-producing probiotic microorganisms. Also described herein are methods of using such engineered microorganisms, such as for reduction of bioavailable methionine or for treatment of a methionine-associated disease or disorder. Also described herein are probiotic dietary supplements, pharmaceutical compositions, and food compositions comprising such engineered microorganisms.

An oral care composition is provided and includes a natural flavor extract, a sulfur source such as dimethyl disulfide, a stannous ion source, and a soluble metal ion source that prevents the formation of methyl mercaptan. The natural flavor extract may contain dimethyl disulfide as an impurity. The soluble metal ion source may include a metal salt, a metal oxide, or a combination thereof, and the soluble metal ion source may include a copper ion source, a silver ion source, a zinc ion source, or combinations thereof.

The invention discloses a preparation process of 2-chloro-4-(methylsulfonyl)-3-methyl benzoic acid, and relates to the technical field of preparation of inorganic compounds. The invention relates to a preparation process of 2-chloro-4-(methylsulfonyl)-3-methyl benzoic acid, which comprises the following steps: reacting 3-chloro-2-methylaniline with hydrochloric acid and sodium methyl mercaptide to form an intermediate C1, reacting with acetyl chloride, catalyzing with anhydrous aluminum trichloride to form an intermediate C2, reacting with hydrogen peroxide and sodium hypochlorite to form an intermediate C4, and reacting with sodium chloride to form the 2-chloro-4-(methylsulfonyl)-3-methyl benzoic acid. The 2-chloro-4-(methylsulfonyl)-3-methyl benzoic acid is obtained after the reaction is completed.

The invention discloses a recombinant O-acetyl-L-homoserine mercaptotransferase mutant, a recombinant genetically engineered bacterium and application of the recombinant O-acetyl-L-homoserine mercaptotransferase mutant and the recombinant genetically engineered bacterium. The mutant is obtained by performing single mutation or multiple mutation on the 33rd site, the 55th site, the 237th site and the 238th site of an amino acid sequence shown in SEQ ID NO.2. The method has the beneficial effects that the method has more efficient catalytic activity and stronger substrate tolerance, has the advantages of mild conditions, less discharge of three wastes, high selectivity and high product yield when being used for catalyzing OAH and sodium methyl mercaptide to synthesize L-methionine, and has a wide development space in the aspect of industrial production of L-methionine.

The present invention provides a process and its application of a tandem biological trickling filter tower with a combined bacterial solution of Alkaligenes aquatilis SW9 and Chryseobacterium MTW1 produced from water, comprising the following steps: S1: Inoculate the fermented bacterial solutions of the two strains in series into the packing of the biological trickling filter tower. The packing of the biological trickling filter tower consists of two biological trickling filter towers in series. The first biological trickling filter tower is inoculated with Alkaligenes aquatilis SW9 for film formation, and the second biological trickling filter tower is inoculated with Chryseobacterium MTW1 for film formation. The film formation time is 24 hours; S2: Ensure that the total concentration of viable bacteria attached to the packing of the biological trickling filter tower is 1×10 8 CFU / mL, and the residence time of the malodorous gas in the biological trickling filter tower is 45 s. By combining highly efficient deodorizing strains with the biological trickling filter tower technology, the present invention purifies malodorous waste gas, can remove hydrogen sulfide, methanethiol and a composite gas of hydrogen sulfide and methanethiol at a relatively high concentration, and has the characteristics of high deodorization efficiency and high deodorization concentration compared with the existing deodorization technologies.

The invention provides an odorless catalytic material as well as a preparation method and application thereof. The odorless catalytic material comprises a honeycomb substrate, and the honeycomb substrate is loaded with a hydrogen type molecular sieve active component and an oxygen vacancy type active component. The odorless catalytic material belongs to a synergistic system of an oxygen vacancy mechanism and an acid-base catalytic mechanism, not only can remove various peculiar smells such as amines, mercaptans and thioethers at the same time, but also can show excellent catalytic efficiency under the low-temperature condition of refrigeration equipment. In the odor-removing catalytic material, the surface of the hydrogen-type molecular sieve is in an acidic state, so that the hydrogen-type molecular sieve has a good effect on thioethers; the oxygen vacancy type active component has an excellent effect on both trimethylamine and methyl mercaptan. The invention also provides a preparation method and application of the odor-removing catalytic material.

The invention discloses a preparation method of a K-WS2 / g-C3N4 nanosheet and a desulfurization application of the K-WS2 / g-C3N4 nanosheet. The method comprises the following steps: mixing a compound containing a triazine structure, carrying out ball milling, roasting to obtain a g-C3N4 nanosheet, loading potassium tungstate, and carrying out in-situ vulcanization to obtain the K-WS2 / g-C3N4 nanosheet catalyst. The raw materials can be fully mixed and particles can be refined in the ball milling process, the reaction contact area is increased, meanwhile, fracture and recombination of chemical bonds can be promoted through the mechanical force effect, and stable g-C3N4 can be generated in the subsequent roasting process. A more stable active component K-WS2 can be obtained through in-situ vulcanization of potassium tungstate, and the active component K-WS2 has natural tolerance to H2S and can effectively avoid the problem of sulfur poisoning. The g-C3N4 nanosheet can promote full exposure of active sites of the catalyst, so that reaction raw materials are in full contact with the active sites of the catalyst. The cooperation of the active sites and the carrier with high specific surface area can efficiently catalyze H2S and CO2 hydrogenation to prepare methyl mercaptan.

The present invention discloses an oral gas detection method and device for children. The method includes: obtaining an oral gas detection information set of children with different types of health status information; the oral gas detection information set includes a number of oral gas detection information corresponding to each type of health status information; the oral gas detection information includes a hydrogen sulfide content sequence value, a methanethiol content sequence value, and a dimethyl sulfide content sequence value; performing correlation analysis processing on the health status information and the oral gas detection information set to obtain a gas correlation model; analyzing the components of the collected oral gas of children to obtain gas component detection result information; using the gas correlation model to perform identification processing on the gas component detection result information to obtain children's health status information. The present invention realizes the accurate detection of children's physical status through the full detection and feature extraction of children's oral gas information.

An absorbent article (1) is provided with a surface sheet (2), an absorbent body (4) containing a water-absorbent polymer, and an activated carbon member (5) containing activated carbon particles disposed apart from the absorbent body (4). A water-absorbing polymer contained in an absorber (4) and an activated carbon member (5) are disposed so as to satisfy the conditions represented by formula (1) in a deodorization function test in which the activated carbon member (5) is disposed in a closed space. A first odor component amount, which is the amount of an odor component including a basic odor caused by ammonia or trimethylamine and an acidic odor caused by methyl mercaptan, in the sealed space after three hours in a state in which urine is to be absorbed by the absorbent article (1), is measured. And a second odor component amount, which is the amount of an odor component in the closed space after three hours in a state in which urine is left to be absorbed by the absorbent article (1), is measured, and the first odor component amount / the second odor component amount is less than or equal to 0.07 (1).

This invention discloses an electrochemical synthesis method for methylthiopyrazole derivatives, comprising the following steps: The electrochemical synthesis method for methylthiopyrazole derivatives provided by this invention is a novel electrochemical synthesis method for constructing C-H methylthiolation of pyrazole derivatives using potassium thiocyanate as the sulfiding reagent and alcohol as the methylating reagent. Compared with traditional preparation methods, thiocyanate as the sulfiding reagent is not only simple and readily available, but also avoids the addition of external electrolytes. Simultaneously, the electrochemical conditions are milder and more sustainable, requiring no metal catalysts or oxidants, avoiding the use of highly toxic sulfur reagents, and exhibiting green and efficient characteristics.

The invention relates to the technical field of catalytic synthesis, in particular to an oxidation catalyst, a preparation method and application thereof and a methanesulfonic acid preparation method. The oxidation catalyst comprises a carrier and an active component loaded on the carrier, the active component is prepared from OsO4, PtO2, MoO, TiO2 and V2O5; the carrier comprises Al2O3 modified by a Ce element; on the basis that the weight percentage of the carrier is 100%, the active components comprise the following components in percentage by weight: 0.06%-4% of OsO4, 0.01%-3% of PtO2, 0.005%-2% of MoO, 0.05%-1% of TiO2 and 0.06%-2% of V2O5. The oxidation catalyst is used for catalyzing sodium methyl mercaptide to oxidize and prepare methanesulfonic acid, the reaction efficiency is high, the reaction condition is mild, and the atom economy is very high.

An oral care composition is provided and includes hops acid, a tin ion source, a sulfur source, and a soluble metal salt that prevents the formation of methyl mercaptan. The soluble metal salt may include a copper salt, a silver salt, a zinc salt, or combinations thereof. The hops acid may be from a hops extract. The sulfur source may be an impurity, and the soluble metal salt may prevent the formation of unacceptable off-notes, which may be produced in the composition under reducing conditions.

The application discloses a catalyst for catalyzing COS / H2S to synthesize methyl mercaptan and a preparation method thereof, and belongs to the technical field of catalysts. The catalyst is spherical alumina, and the preparation method comprises the following steps: dissolving alumina precursors, a sulfate and a precipitating agent in water to obtain a mixed solution, and performing a hydrothermal reaction by heating; and after the hydrothermal reaction is completed, cooling, filtering, washing, drying and calcining are performed to obtain the spherical alumina catalyst. The spherical alumina catalyst is prepared by a hydrothermal and calcination method, the catalyst has a unique microsphere structure and acid-base sites, can provide more active centers and a better reaction environment, greatly enhances the activity and selectivity of COS / H2S in synthesizing methyl mercaptan, and thus has a better catalytic effect in a reaction related to COS / H2S cooperative removal and resource synthesis of methyl mercaptan.

The invention belongs to the field of pesticide chemicals, and in particular to a kind of synthetic method of acephate. Phosphorus oxychloride and methanol generate methyl dichlorophosphate through substitution reaction, methyl dichlorophosphate and ammonia generate methylphosphoramide chloride through acylation reaction, methylphosphoramide chloride and methyl mercaptan obtain methylamidophos through substitution reaction, and methylamidophos and acetic anhydride generate acephate through acylation reaction. Using phosphorus oxychloride as raw material, by multiple substitution reactions and one-step acylation reaction, target product can be obtained, avoiding the reaction of phosphorus trichloride and sulfur under high temperature conditions and the isomerization reaction of O, O-dimethylthiophosphoramide, and the use of caustic alkali. Meanwhile, the product appearance properties prepared by the inventive method are good.

This invention discloses a method for removing methanethiol from kitchen waste during disposal using KOH-modified biochar activated with persulfate. The method first prepares KOH-modified biochar using walnut shell powder and KOH. Then, the KOH-modified biochar, persulfate, and water are added to a reaction apparatus. Methanethiol from the kitchen waste disposal process is introduced into the reaction apparatus, where a bubble generator produces bubbles, ensuring sufficient contact between the methanethiol and the KOH-modified biochar and persulfate. Through adsorption and catalytic oxidation, the methanethiol is removed. This method can continuously and efficiently remove methanethiol under conventional conditions, maintaining a removal rate of approximately 91% per hour. It has advantages such as high removal efficiency, simple operation, and low cost.

The invention relates to a method for preparing L-methionine by catalyzing homoserine and methyl mercaptan to react through an enzyme. The method does not include a step of producing O-acyl-L-homoserine, and / or the method does not use O-acyl-L-homoserine.

The invention belongs to the technical field of photocatalytic materials, and particularly discloses a preparation method of an amino-rich ordered carbon nitride nanosheet catalyst and application of the amino-rich ordered carbon nitride nanosheet catalyst in photocatalytic degradation of methyl mercaptan. Aiming at the problems of insufficient surface active sites, high photon-generated carrier recombination rate and the like of an existing carbon nitride material, carbon nitride is subjected to secondary thermal polymerization in an ammonia atmosphere through an ammonia-assisted thermal polymerization reconstruction strategy, and a carbon nitride nanosheet catalyst with high-density surface amino groups and a layered ordered structure is formed through induction. The amino-rich ordered carbon nitride nanosheet catalyst prepared by the invention can realize high-efficiency degradation of methyl mercaptan under the conditions of room temperature and visible light. The technical system has the advantages of low reaction energy consumption, high degradation efficiency, mild operation conditions and the like, and meets the actual production requirements; the catalyst shows excellent photocatalytic activity and stability, is suitable for large-scale industrial production, and has a good industrial application prospect.

This invention relates to the field of herbicide technology, specifically to a method for preparing a sulfadiazine intermediate, comprising: (1) reacting 3,4-dichloronitrobenzene, methyl cyanoacetate, and a first base in the presence of a first solvent to obtain a compound of formula (II); (2) reacting the compound of formula (II) with sodium methanethiol in the presence of a second solvent to obtain a compound of formula (III); and (3) reacting the compound of formula (III) with a second base and hydrogen peroxide in the presence of a third solvent to obtain the sulfadiazine intermediate of formula (I). This method has the advantages of mild reaction conditions, high reaction yield and purity, and low cost, making it suitable for industrial production.

According to the composite microbial preparation for pet deodorization and the preparation method and application thereof, the composite microbial preparation obtained through compounding of various strains has the pet odor treatment efficiency higher than 85% after being applied for 24 h, the ammonia gas treatment efficiency can reach 92.5% or above, the hydrogen sulfide treatment efficiency can reach 90% or above, and the pet odor treatment efficiency can reach 90% or above. The treatment efficiency of methyl mercaptan can reach 86% or above, deodorization is lasting and efficient, and secondary pollution is avoided.

The application discloses a methanethiol synthesis catalyst with a wide hydrogen sulfide to methanol ratio and a preparation method thereof. The catalyst comprises the following components in parts of mass: 1-10 parts of magnesium oxide, 60-80 parts of aluminum oxide, 10-25 parts of potassium tungstate and 2-10 parts of vanadium pentoxide. The catalyst can keep high activity, high selectivity and long service life in a wide methanethiol ratio range, and has wide application value.

This invention relates to the field of adsorption and filtration material preparation technology, specifically a multifunctional composite air purification filter material and its preparation method. It includes the following steps: S1, a method for preparing transition metal ion-modified carbon; S2, a filter material composite method. Compared with existing technologies, this invention provides a multifunctional composite air purification filter material and its preparation method. Modified activated carbon can remove sulfur and nitrogen compounds and odorous gases that are difficult to adsorb conventionally through ion network interaction. The use of copper sulfate, zinc sulfate, and 2-aminoimidazole synergistically can effectively complex and adsorb odorous gases with low olfactory thresholds, such as trimethylamine and methanethiol, which are difficult to treat. This modified activated carbon is then embedded between an activated manganese catalytic framework cloth and an electrostatic meltblown cloth, maintaining an extremely low filter material thickness, thus achieving efficient removal of formaldehyde, particulate matter, and odors from a single filter material.

The invention relates to a bacterium enzyme composite deodorant and application thereof, which can effectively improve the digestive function of the gastrointestinal tract of a piglet to promote the growth of the piglet, obviously reduce the emission of volatile malodorous substances in excrement, and provide a new feed additive for healthy breeding of the piglet and improvement of the breeding environment. Wherein the compound bacteria are prepared by uniformly mixing lactobacillus plantarum, saccharomyces cerevisiae and bacillus licheniformis according to the weight ratio of 3: 2: 1, the compound enzyme is prepared by uniformly mixing protease and amylase according to the weight ratio of 1: 25, and the compound bacteria and the compound enzyme are uniformly mixed according to the weight ratio of 2: 1. As a feed additive, the feed additive can significantly improve the average daily gain of piglets, improve the digestive function of intestinal tracts of the piglets, improve the growth performance of the piglets, reduce the feed-gain ratio, effectively reduce the pH value and the water content of excrement and reduce emission of volatile malodorous substances such as ammonia gas, hydrogen sulfide and methyl mercaptan, and is an efficient, green, ecological and safe feed additive. The method has popularization and application value in various pig farms.

This invention discloses a halitosis-eliminating toothpaste containing galangal extract and its preparation process. The toothpaste comprises a galangal volatile oil-cyclodextrin inclusion complex and / or positively charged nanoparticles loaded with galangal flavonoids, as well as a pH adjuster, sodium bicarbonate. Ethyl p-methoxycinnamate and ethyl cinnamate in the galangal volatile oil undergo a Michael addition reaction with methanethiol under weakly alkaline conditions, rapidly neutralizing existing odor-causing sulfides. The positively charged nanoparticles are electrostatically adsorbed onto the tooth surface, slowly releasing flavonoids and providing long-lasting inhibition of odor-producing bacteria. The preparation process includes gel preparation, graded pre-dispersion, sequential addition and mixing, and vacuum degassing, further specifying the preparation methods of the inclusion complex and nanoparticles. This invention is free of metal ions and chemical bactericides, achieving immediate neutralization and long-lasting antibacterial synergy, and is characterized by safety, stability, naturalness, and high efficiency in eliminating halitosis.

An oral care composition is provided and includes hops acid, a tin ion source, a sulfur source, and a soluble metal salt that prevents the formation of methyl mercaptan. The soluble metal salt may include a copper salt, a silver salt, a zinc salt, or combinations thereof. The hops acid may be from a hops extract. The sulfur source may be an impurity, and the soluble metal salt may prevent the formation of unacceptable off-notes, which may be produced in the composition under reducing conditions.

The invention discloses a deodorization composition for long-acting inhibition of sulfur-nitrogen odor and a preparation method thereof. The composition comprises the following components in parts by weight: 1-5 parts of an oxidizing agent, 10-40 parts of an acid neutralizer, 5-20 parts of a pH buffer agent, 80-120 parts of an adsorbent, 5-20 parts of an inclusion agent and 1-2 parts of a bacteriostatic agent. Through cooperation of multiple mechanisms of oxidation, neutralization, adsorption, inclusion and bacteriostasis, efficient and lasting removal of ammonia gas, methyl mercaptan and other composite odors is realized. The composition is in the form of solid powder and is suitable for hygienic products such as paper diapers and pet padding. The preparation method comprises the following steps: crushing and sieving the components in a dry environment, uniformly mixing a small amount of components with the same amount of other components, and gradually mixing the mixture with the rest components in batches until all the components are fully and uniformly mixed. The composition is low in cost, good in stability and high in deodorization rate, and has a good industrial application prospect.

The invention provides a chromatographic analysis method of methyl mercaptan. The chromatographic analysis method comprises the following steps: providing a liquid methyl mercaptan sample under the pressure of 1-3 MPa; a liquid methyl mercaptan sample is conveyed into a gas chromatograph through a high-pressure liquid sample injection valve and is separated and detected through two analysis paths, wherein the first analysis path comprises that the vaporized sample sequentially enters a first chromatographic column and a second chromatographic column for limiting flow to be separated; the second analysis path comprises the following steps: intercepting fractions flowing out of the first chromatographic column from the vaporized sample entering the first chromatographic column according to a preset time window through a center cutting technology in a microflow plate center cutting system, and then cutting the fractions into a third chromatographic column for re-separation; the first chromatographic column is a non-polar capillary column or a weak-polar capillary column, the second chromatographic column is an empty white chromatographic column, and the third chromatographic column is a polar or medium-polar capillary column. The invention provides complete off-line analysis for high-purity liquid methyl mercaptan samples from sample stabilization to efficient quantitative and qualitative analysis and separation of impurities.

The utility model provides a kind of methyl mercaptan synthesis device, using self-made catalyst in fixed bed reactor catalysis hydrogen sulfide and methanol reaction to obtain methyl mercaptan. After methanol is vaporized, it is mixed with hydrogen sulfide and enters preheater to preheat, then enters reactor, and mixed gas passes through the reactor filled with catalyst from top to bottom, and methyl mercaptan is obtained under certain temperature and pressure. The reaction principle of the device is simple, has raw material price advantage, and the catalyst obtained can be used to catalyze the reaction of methanol and hydrogen sulfide to generate methyl mercaptan, with the advantages of high selectivity and stability, and the device can realize continuous production.