34results about How to "Avoid by-products" patented technology

The invention relates to a 5'-phosphoric acid and fluorescence end-labeled nucleotide and provides a molecular structure and a synthetic method thereof. The 5'-phosphoric acid and fluorescence end-labeled nucleotide is better recognizable to DNA (deoxyribonucleic acid) polymerases; after recognized by the polymerases and correctly combined with the same, by the aid of alkaline phosphatase, the 5'-phosphoric acid and fluorescence end-labeled nucleotide allows a fluorescent signal to quickly change from closure to opening; thus the 5'-phosphoric acid and fluorescence end-labeled nucleotide can serve as the polymerase substrate applicable to the fields such as nucleic acid sequencing.

There is provided a reaction vessel whereby silicon produced can be smoothly recovered dropwise without excessive thermal load on constitutional parts of the reaction vessel, a silicon deposition feedstock gas can be reacted efficiently even when the reaction vessel is scaled up to industrial large-scale equipment, generation of silicon fine powder and silane oligomers can be suppressed, and industrial silicon production can be performed over extended periods. The tubular reaction vessel comprises a longitudinally-extending wall with a space thereinside, wherein a silicon deposition feedstock gas inflow opening and a deposited silicon discharge opening are provided at an upper portion and a lower end portion respectively, and a flow resistance-increasing region is created on a wall surface of the tubular reaction vessel that is contacted with a feedstock gas. The flow resistance-increasing region is at least one of protrudent, concave and sloped regions.

The invention relates to a method for synthesizing a trans-4-(trans-4'-alkylcyclohexyl)cyclohexylethylene liquid crystal. A desired product is prepared from trans-4-(trans-4'-alkylcyclohexyl)cyclohexylethanone as a raw material through alpha-bromination, reduction, intramolecular etherification, ring-opening bromination and debromination alkene formation. The method has the advantages of easy availability of raw materials, high yield of various steps, easy purification of products and low cost. The entire route uses cheap toluene, ethanol and methanol as solvents, prevents the problems of lowatomic utilization and many by-products of the wittig reaction and prevents the environmental problems produced by highly concentrated tetrahydrofuran wastewater. Environmental friendliness is one ofthe highlights of the route.

The invention discloses a method for synthesizing 1,2,4-butanetriol by enzymatic reaction. The method is characterized in that D-xylose dehydrogenase, D-xylonic acid dehydratase, benzoylformate decarboxylase and alcohol dehydrogenase are taken as catalysts for catalyzing conversion of D-xylose into D-1,2,4-butanetriol in a reaction system. The reaction system contains the following components: PBS(NaHPO4 and NaH2PO4) with concentration being 50 mM, NAD<+> with concentration being 0.5 mM, NADH with concentration being 0.5mM and TPP with concentration being 0.4 mM. The capability of synthesizing butanetriol in vitro is improved by controlling the quantity of enzymes, and the adverse effects of multiple byproducts, complex subsequent separation process and the like caused by a microbial synthesis method are avoided.

L-Glutamine is produced by culturing a coryneform bacterium which has L-glutamine producing ability and has been modified so that its intracellular glutamine synthetase activity should be enhanced, preferably which has been further modified so that its intracellular glutamate dehydrogenase activity should be enhanced, in a medium to produce and accumulate L-glutamine in the medium and collecting the L-glutamine.

The invention provides an industrial manufacturing method of glycerol phosphocholine. The industrial manufacturing method is characterized by comprising the following steps of reacting a compound A as a raw material and sodium salt or potassium salt to produce a compound B, carrying out ion exchange to produce a compound C and reacting the compound C and glycidol to produce glycerol phosphocholine. The method can be continuously completed in a one-pot process, step-by-step purification process of intermediate products is not needed, foreign reagents such as a catalyst do not need to be added, the final pure product can be obtained by only removing the reaction solvent, the operation is extremely convenient, the raw materials are low in cost and the yield can be not less than 90%.

The present invention provides a method for preparing an in-situ ternary nanoparticle-reinforced aluminum matrix composite (AMC). In this method, an in-situ reaction generation technique is used, and with a powder containing formation elements for producing reinforcing particles as a reactant, in conjunction with a low-frequency rotating magnetic field/ultrasonic field regulation technique, an aluminum-based composite material is prepared using nanoparticle intermediate alloy re-melting. An AA6016-based composite material reinforced by ternary nanoparticles has an average particle size of 65 nm, and has an obvious refinement phenomenon compared with unitary and dual-phase nanoparticles.

The invention discloses a synthetic method of 2-sulfydryl-1-alkyl imidazole and belongs to the technical field of organic synthesis. The synthetic method comprises the following steps: in the presence of inorganic base, raising the temperature and then carrying out a sealing reaction on imidazole and alkyl halide to obtain 1-alkyl imidazole; dissolving 1-alkyl imidazole into an ether solvent, and adding 1 to 1.1 equivalent amount of butyl lithium at low temperature; then adding 0.9 to 0.95 equivalent amount of sulfur powder for carrying out a reflux reaction and adding acetylchloride after cooling to obtain 2-ethanethioate-1-alkyl imidazole; and finally, dissolving the 2-ethanethioate-1-alkyl imidazole into an alcohol solvent, adding hydrogen chloride or potassium carbonate with the catalytic amount for deprotection, thus obtaining the 2-sulfydryl-1-alkyl imidazole. The 2-sulfydryl-1-alkyl imidazole disclosed by the invention has the advantages of low price of raw materials and higher environmental-friendly property; in addition, the synthetic method is convenient to operate; and the quality of a product meets application standards of electronic chemicals.

The invention provides a method for preparing tildipirosin, which comprises the following steps of: performing a primary hydrolysis reaction on tylosin or salt thereof in an acid solution with the pH value of 1-3 to generate a compound as shown in a formula 1; performing a reductive amination reaction on the compound as shown in the formula 1 and piperidine under the condition of existence of a reducing agent to generate a compound as shown in a formula 2; performing a secondary hydrolysis reaction on the compound as shown in the formula 2 in an acid solution to generate a compound as shown in a formula 3; performing a sulfonic acid esterification reaction on the compound as shown in the formula 3 and a sulfonic acid esterification reagent to generate a compound as shown in a formula 4; and performing an amination reaction on the compound as shown in the formula 4 and piperidine to generate the tildipirosin. The method is mild in reaction condition, has few side reactions, is high in yield, low in cost, simple to operate, and suitable for industrial large-scale production.

Provided is a method for preparing silodosin. Also provided is a method for preparing an organic acid salt of a new intermediate 3-(7-cyano-5-((R)-2-((R)-1-phenylethylamino)propyl)-1-hydrogen-indolyl) propyl alcohol (ester or ether), and a new intermediate 3-(7-cyano-5-((R)-2-(((R)-1-phenethyl)(2-(2-(trifluoroethoxy)phenoxy) ethyl)amino)propyl)1-hydrogen-indolyl)propyl alcohol (ester or ether) and a salt thereof. The method has the following advantages: raw materials are cheap and easy to obtain, the operation is simple, the intermediate and product are easy to purify, the yield is high, and the method is applicable to industrial production.

The invention relates to a method for manufacturing MOS transistor with metal silicide on source and drain. The technical steps are as follows: First dielectric substance layer, conductor layer, second dielectric substance layer are formed on silicon substrate. Eliminating part of the second dielectric substance layer and part of the conductor layer in procedure of transferring pattern forms a grid structure. Gap wall is formed on side wall of the grid structure. Metal granule is adulterated to silicon substrate, where the granule can penetrate through first dielectric substance layer to the silicon substrate, but can not penetrate through the second dielectric substance layer to the conductor layer. Heat-treatment step is carried on to form metal silicide layer on the silicon substrate and eliminate the non-reacted part of metal granule.

The invention discloses an embolism microsphere capable of being secondarily expanded. The invention relates to a water-based adhesive which is prepared from vinyl pyrrolidone, acrylic acid, sodium acrylate, methacrylic acid, sodium methacrylate, acrylamide, 2-acrylamide-2-methyl propanesulfonic acid, 2-acrylamide-2-methyl propanesulfonic acid sodium salt, allylamine, allylamine hydrochloride, dimethyl diallyl ammonium chloride and water. The preparation method comprises the following steps: carrying out cross-linking polymerization on one or more monomers in methyl acryloyl ethyl sulphobetaine to obtain a microsphere, carrying out primary expansion on the microsphere in pure water at 20 DEG C for 1-2 hours until the diameter is 2-3 times that of the microsphere in a dry state, taking out the microsphere, putting the microsphere in a PBS (Phosphate Buffer Solution) with a pH value of 7.4 at 37 DEG C for 48-72 hours, and carrying out secondary expansion, so that the diameter of the microsphere expanded again is increased by 10-30% compared with that of the microsphere expanded for the first time, and the diameter of the microsphere expanded again is increased by 10-30% compared with that of the microsphere expanded for the first time. According to the present invention, the suppository can primarily swell in water or a drug solution, can swell again in the blood vessel environment at the body temperature after being conveyed to the embolism position in the blood vessel, has characteristics of slow swelling speed, limited swelling rate, safety and controllability, can fully fit the shape of the blood vessel, can strengthen the embolism effect, and can easily achieve permanent embolism;

The invention discloses a method for synthesizing 6-chloro-2-(thienyl-2-yl)quinazoline. The method comprises: orderly adding (2-amino-5-chlorophenyl)methanol, 2-thiophenecarbonitrile, a catalyst, a base and a solvent into a reactor and carrying out magnetic stirring in air for a full reaction in an oil bath pot. The method utilizes alcohol as a starting material for the formation of C-N bonds andthe alcohol is cheap, easy to treat and environmentally friendly. The method solves the problem that the conventional method utilizes various oxidizing agents to produce a large amount of by-products.The method utilizes an NNN type pincerlike metal ruthenium (II) compound as a catalyst for the catalytic reaction so that the reaction is finished in one step, the reaction time is greatly shortened,operation is simple and the reaction efficiency is high. The method satisfies the green chemistry sustainable development requirements.

The invention relates to a process for preparing symmetric pincer ligands from a group of M-terphenyl compounds. Concretely, the invention relates to a method for preparing ABA compounds and enabling reaction between compounds of formula (A) and compounds of formula (B). With X=-OR' or -NHR'and R'=H or a protecting group function and R1, R2,R3,R4, R5, R6, R7 and R8 are each independently selected from the group comprising hydrogen, (C1-C12)-alkyl, O-(C1-C12)-alkyl, (C6-C20)-aryl, O-(C6-C20)-aryl, where two of the R1 to R4 radicals may also be joined via a covalent bond, and halogen, which is characterized in that the reaction is conducted electrochemically.

A production system of 1, 2-cyclohexanediamine comprises a solid-liquid separation device, a dehydrating tower, a decoking tower and a refining tower. A material inlet of the solid-liquid separation device is used for being connected with a mixed material source which is discharged by a reactor and subjected to gas-liquid separation, catalyst filtration and dealcoholization. The solid-liquid separation device supplies materials to the dehydrating tower through an overflow pipe. A tower bottom discharge hole of the dehydrating tower supplies materials to the decoking tower through a first pipeline. A tower top discharge hole of the decoking tower supplies materials to the refining tower through a second pipeline. A tower top discharge hole of the refining tower is connected with a return pipeline through a condenser. A return tank, a discharge pump and a first valve are sequentially arranged on the return pipeline. The downstream end of the return pipeline is connected with a return port of the refining tower, a discharge pipe is connected to the return pipeline and located between the discharge pump and the first valve, and a second valve is arranged on the discharge pipe. The system is simple in structure and convenient to operate, can continuously and stably produce 1, 2-cyclohexanediamine products, and meets the actual requirements of chemical enterprises.

The invention relates to a preparation method of imidic acid or hydrochloride thereof, which belongs to the technical field of medicine synthesis. In order to solve the problems of easy salification and low yield in the prior art, the invention provides a preparation method of imidic acid or hydrochloride thereof, which comprises the following steps of in the presence of an acid application agent,reacting 4-halogenated methyl acetophenone with N-methylpiperazine to obtain a corresponding intermediate, under the action of pypocholoride, enabling the intermediate to be subjected to an oxidationreaction to obtain corresponding imidic acid, when the imidic acid hydrochloride is synthesized, after the oxidation reaction is finished, adjusting the pH value to be strongly acidic, so that the corresponding imidic acid hydrochloride is formed. According to the method, the reaction has the effect of high conversion rate during condensation, byproducts of salifying reaction products are effectively avoided, raw material residues can be effectively controlled to be less than 0.2%, and the method has the effect of high product yield.

The invention relates to a preparation method of a SiO2 aerogel/activated carbon composite material adsorbent, and belongs to the technical field of adsorption materials. The preparation method is characterized in that a sol-gel process is adopted; the SiO2 aerogel/activated carbon composite material is prepared by taking sodium silicate as a silicon source and deionized water as a solvent, respectively preparing HCl and ammonia water with certain concentrations as catalysts, adding different amounts of activated carbon and adopting a normal-pressure drying process, the preparation process issimple, the raw materials are cheap and easy to obtain, the preparation period is short, and the prepared material is stable in chemical property. The composite adsorbing material prepared by the invention has a relatively large specific surface area, can effectively adsorb chromium ions in wastewater, and has a very good application prospect.

The invention provides a curing agent for carboxyl resin as well as a preparation method and an application of the curing agent. The curing agent is prepared from main raw materials including phenyl polyacid, phenyl polyphenol, sodium hydroxide, allyl bromide, epichlorohydrin and a catalyst through joint reaction. The curing agent contains both epoxy groups and double-bond groups, so that the curing agent can be subjected to a reaction with carboxyl groups in branch chains of carboxyl acrylic resin and can also be subjected to a reaction with double bonds remaining in main chains, and a densefilm with higher crosslinking density is formed.