94 results about "Selective degradation" patented technology

A bioabsorbable polymeric stent with time dependent structure and properties and methods of treating a diseased blood vessel with the bioabsorable polymeric stent are disclosed. The structure and properties of the stent change with time and allow the vessel to be restored to a natural unstented state. The bioabsorbable stent loses mechanical integrity in a controlled manner due to modification of selected structural elements.

The invention discloses a modified asphalt and a processing method of the modified asphalt. The modified asphalt of the invention contains the following components in part by weight: 50 to 92 parts by weight of base asphalt, 8 to 50 parts by weight of rubber powder, 0.1 to 5 parts by weight of first cross-linking agent, 0 to 12 parts by weight of diluent and 0 to 6 parts by weight of second cross-linking agent. The invention develops a modified asphalt prepared through desulphurization degradation and recrosslinking and the processing method of the modified asphalt through the analysis of the conditions of selective degradation process of waste rubber powder in the asphalt, the recovery of macro molecules performance of the degraded waste rubber powder in the modified asphalt and the study on the preparation technique of the modified asphalt made of the waste rubber powder. The modified asphalt can form homogeneous mixing system, the viscosity of the asphalt is reduced and the storage stability is increased.

The invention provides a method of probing for a nucleic acid comprising: contacting a nucleic acid solution with an oligonucleotide probe labelled with an electrochemically active marker, providing conditions at which the probe is able to at least partially hybridise with any complementary target sequence which may be present in the nucleic acid solution, selectively degrading either hybridised, partially hybridised or unhybridised nucleic acid probe, and electrochemically determining information relating to the electrochemically active marker. The invention further provides novel molecules with use in methods of the invention.

Generally provided are methods for rapid culture of microorganisms in a sample, including methods for growth and recovery of live microbial cells directly from a sample. Various features include enabling growth of microorganisms in a sample along with a reduction of sample debris that may interfere with microorganism detection, and reduction in toxicities that may inhibit microorganism growth. Further methods for selectively degrading non-viable microbial cells, are provided, for enhanced detection of viable microbial cells following a growth period.

Stevioside is a novel sweeter which is extracted from stevia leaves, and the stevioside in the stevia leaves mainly comprises two components of stevioside and rebaudioside A. The sweetness and mouthfeel of the rebaudioside A are both excellent, while the stevioside has certain lingering bitterness; and as the structure and nature of the rebaudioside A are approximate to the structure and nature of the stevioside, the separation of rebaudioside A and stevioside features high cost and great technical difficulty. In the invention, microorganisms are transformed for 20h-150h under the conditions that the concentration of the stevioside is 0.01%-5% (W/W), the temperature is 25-80 DEG C, the quantity of inverting enzyme or bacterial solution is 0.1%-10% (W/W), and the pH value is 2.0-7.0, and the stevioside contained in the rebaudioside A solution can be selectively degraded, thus obtaining high purity rebaudioside A containing no stevioside. The biotransformation method used in the invention has temperate conditions, does not use toxic methanol and other chemicals or macroporous resin with high cost, thus being a novel technology with safety, greenness and environmental friendliness.

The invention provides a 4-substituted naphthalimide compound and a use thereof. The compound has a structure shown in the general formula I. The compound can competitively bind and antagonize with Bcl-2 and Mcl-1 proteins in vitro and in cells so that apoptosis is induced and thus the compound is a high activity apoptosis inducing agent and an antitumor compound. The derivative based on the compound can be used as a bifunctional molecule for external and intracellular recognition, separation, enrichment and fluorescence detection of Bcl-2 family proteins or can be used as a PROTAC bifunctional complex for intracellular selective degradation of Bcl-2 and Mcl-1 proteins so that the level of the Bcl-2 family proteins in living cells can be adjusted and controlled.

The invention relates to an artificial antibody type titanium dioxide (TiO2)/ boron-doped diamond (BDD) membrane electrode and a preparation method thereof, the electrode is in p-n heterostructure, the electrode uses boron-doped diamond (BDD) as a substrate, uniform dense fusiform TiO2 particles are on the surface of the BDD, the particle size of the TiO2 particles is 50-100nm, a modification layer with a thickness of 5 to 10 mum is formed by the densely covered TiO2 particles; the preparation method of the artificial antibody type titanium dioxide (TiO2)/ boron-doped diamond (BDD) membrane electrode is as follows: using of the boron-doped diamond as the substrate, low temperature liquid phase deposition of TiO2 with a target pollutant molecular imprinting on the surface of the substrate, and removal of target pollutant molecules. Compared with the prior art, the artificial antibody type titanium dioxide (TiO2)/ boron-doped diamond (BDD) membrane electrode prepared by the method both has the p-n heterostructure and target pollutant molecular recognition ability, has excellent photoelectrocatalytic integrative performance and high selectivity degradation ability, has the advantages of simple preparation process, can be effectively used for removal of organic pollutants with low concentration, low tendency to biochemistry and high toxicity, and has extensive economic and social benefits.

The invention provides a molecular imprinting catalytic membrane capable of selectively degrading ciprofloxacin and a preparation method. The preparation method comprises the following steps: step 1, preparing graphite-like nitrogen carbonate g-C3N4; step 2, preparing a noble metal loaded semiconductor composite material; and step 3, preparing the molecular imprinting catalytic membrane capable of selectively degrading the ciprofloxacin. The material prepared by the preparation method can effectively realize the aims of preferably selectively adsorbing and degrading target pollutants in a mixed sewage system; post-treatment is simple, a photocatalyst is conveniently recycled for a plurality of times and secondary pollution is effectively avoided; and the molecular imprinting catalytic membrane has the advantage of selectively treating antibiotic wastewater very well.

The invention provides a method for synthesizing TiO2 composite photocatalyst with high selectivity and degradation function, belongs to the technical field of new material synthesis, and solves the problem of low selectivity in the prior photocatalysis reaction. The method for synthesizing the TiO2 composite photocatalyst with the high selectivity and the degradation function comprises the following steps: a, preparing titanium dioxide colloidal sol; b, performing hydrolytic condensation; and c, preparing the TiO2 composite photocatalyst. The TiO2 composite photocatalyst synthesized by the method for synthesizing the TiO2 composite photocatalyst with the high selectivity and the degradation function has high selectivity; and the method has the advantages of quick degradation and high degradation efficiency for 2, 4-dichlorophenol, and the like.

The invention provides a selective degradation method for petroleum pollutants in soil rich in organic matters. According to the selective degradation method, a Fenton reagent consisting of hydrogen peroxide and Fe<2+> is taken as an oxidization reagent; and a complex solution of citric acid and calcium chloride is added into a Fe<2+> solution in the Fenton reagent and used as a selective regulator to improve selective oxidative degradation of the Fenton reagent to the petroleum pollutants. TPH (total petroleum hydrocarbons) are selectively degraded by the Fenton reagent, so that the TPH removal rate is increased, the oxidization of SOM (soil organic matter) is reduced, the stability and the utilization rate of hydrogen peroxide in a Fenton system can be improved, and the service life of a hydroxyl radical is prolonged.

The invention discloses a method for degrading polybrominated diphenyl ether by combining surfactant solubilization and UV technology, which belongs to the technical field of environment-friendly halogenated aryl hydrocarbon organic pollutant treatment. The method adopts the technical proposal that surfactant solubilization of 2,2',4,4',5-pentabromated diphenyl ether is improved in a hydrophobic environment provided by nonionic surfactant micelle (Brij 35 or Brij 38) under the conditions of normal temperature and pressure, water bath and ultrasonic sound; and the 2,2',4,4',5-pentabromated diphenyl ether which is dissolved in a surfactant solution is subjected to UV advanced treatment at normal temperature and pressure and then subjected to stepwise debromination reaction or intermolecular elimination and annulation reaction to generate intermediate products, namely PBDEs from monobromo to tetrabromo and polybrominated dibenzofuran (PBDFs) from monobromo to tetrabromo. The whole technology has short time consumption and high efficiency, and the method can selectively degrade target pollutant without damaging a surfactant, provides convenience for recycling of the surfactant, and has good application prospect in the aspect of remediation of soil polluted by the PBDEs in electronic waste recycling sites.

The invention provides a preparation method and application of a molecular print catalytic membrane for selectively degrading tetracycline. The preparation method mainly comprises the steps that 1, an Ag@Au@TiO2 catalyst is prepared; 2, dispersion liquid of the Ag@Au@TiO2 catalyst is prepared; 3, a casting solution is further prepared through the dispersion liquid of the Ag@Au@TiO2 catalyst; 4, a blend membrane is prepared on a glass plate through the casting solution; and 5, the molecular print catalytic membrane for selectively degrading the tetracycline is prepared through the blend membrane. Through the photocatalytic degradation process of the prepared molecular print catalytic membrane for selectively degrading the tetracycline, the purposes of selectively recognizing, adsorbing and catalytically degrading target pollutants can be achieved effectively, aftertreatment is simple and convenient, the effective degradation efficiency of the target substances is improved, and the preparation method has the advantage of higher selectivity of treatment of antibiotic wastewater.

The invention provides a synthesis method and application for imprinting-doped mesoporous TiO2 microspheres. The synthesis method includes dissolving 1-5ml of titanium source substances into 100-200ml of organic solution, adding 0.1-0.3g of catalytic into the organic solution, adding 0.1-0.5g of target molecules used as imprinting molecules while stirring the mixture, and further adding metal salt with the molar ratio ranging from 0.1% to 8% relative to a titanium source so as to introducing doping ions; and continuing stirring for 1-12 hours, then enabling the solution to react in a high-temperature and high-pressure kettle at the temperature ranging from 80 DEG C to 180 DEG C for 3-6 hours, centrifugally washing to obtain white solid, placing the white solid in a muffle furnace at the temperature ranging from 400 DEG C to 450 DEG C, keeping the temperature for 2-4 hours and then obtaining the imprinting-doped mesoporous TiO2 microspheres. The prepared materials are used for degrading target organic pollutant in water, have higher photocatalytic activity as compared with pure TiO2(P25), and are capable of selectively degrading the target pollutant. In addition, the imprinting-doped mesoporous TiO2 microspheres have a wider photoresponse range as compared with pure TiO2 undoped with imprinting, and have high visible light absorption capacity.

The invention provides a ZnS/Bi2O3 heterojunction molecularly-imprinted photocatalytic membrane, a preparation method and an application. The preparation method comprises the following steps: (1) preparing a Bi2O3 photocatalyst; (2) preparing a ZnS/Bi2O3 heterojunction photocatalyst; and (3) preparing a ZnS/Bi2O3 heterojunction molecularly-imprinted photocatalytic membrane. The prepared ZnS/Bi2O3 heterojunction molecularly-imprinted photocatalytic membrane for selectively degrading rhodamine B has the advantages that in the process of photocatalytic degradation, the purposes of selective recognition, absorption and catalytic degradation of target pollutants can be effectively realized, the aftertreatment is simple and convenient, the efficiency of effective degradation of target substances is improved, and the selective treatment of dye waste water is stronger.

The invention discloses a solid photocatalyst with visible-light response and selectivity as well as a preparation method and application of solid photocatalyst. The solid photocatalyst comprises metal semiconductor nanoparticles and a metal complex loaded on the metal semiconductor nanoparticles, wherein the metal semiconductor nanoparticles are selected from at least one of titanium dioxide, tin dioxide, zinc oxide and cadmium sulfide; central metal ions of the metal complex are selected from platinum (II), ruthenium (II) or iron (II), and a ligand in the metal complex is an organic or inorganic ligand; in the solid photocatalyst, the mass content of the metal complex is 1-100mg/g. The solid photocatalyst can be used for selective degradation treatment of low-concentration toxic phenolic pollutants in various low-toxin high-concentration pollutants and selective oxidation of organic matters, also can be used for treating industrial wastewater, and has the characteristics of simple preparation process and high catalytic efficiency.

The invention belongs to the field of carbon materials, and concretely relates to a nitrogen-doped carbon material, and a preparation method and an application thereof. The prearatio method comprisesthe following steps: calcining glucose used as a raw material in an inert atmosphere using melamine used as a nitrogen source to a certain temperature to obtain a carbon substrate, mixing the carbon substrate with melamine in an aqueous solution according to a certain ratio, performing heating and stirring, drying the obtained material, and calcining the dried material in the inert atmosphere at alow temperature in order to obtain the nitrogen-doped carbon material. The preparation method has the advantages of simplicity, low energy consumption and low cost, and the nitrogen-doped carbon material has a very high reactivity, and can selectively degrade a plurality of organic pollutants, so the technical problems of complexity and high cost of preparation methods of the nitrogen-doped carbon material in the prior art and the technical problem of limited ability to degrade the organic pollutants in the environment are solved.

Methods for designing heterobifunctional small molecules which selectively degrade/disrupt CDK4/6 and compositions and methods of using such degraders/disruptors to treat CDK4/6-mediated cancer are provided.

The invention discloses an oil field thermophilic degradation long chain hydrocarbon bacillus HNMC 11117 and application thereof. The preservation number of the bacterial strain is CGMCC No.12204. Extraction liquid of an air inflation well with the oil deposit bottom layer temperature larger than 60 DEG C in Henan Zhongyuan Oil Field is used as an isolation sample, separation, purification, screening and recheck are performed, and the effective bacterial strain being HNMC 11117 bacterial strain which has the selectable degradation effect on alkane with the chain length of C16-C30 is obtained. The bacterial strain can be used for improving oil recovery at high temperature, repairing soil polluted by oil and other fields.

The invention relates to an enzyme treatment and recycling method for protein fibers in waste textiles. The provided method aims to effectively realize the recycling of the protein fibers in the waste textiles. According to the technical scheme provided by the invention, the enzyme treatment and recycling method for the protein fibers in the waste textiles sequentially comprises the following steps: (1) continually carrying out following treatment steps on the waste textiles containing the protein fibers; (2) adding oxidordeuctase into dyed textiles which are directly treated by a direct dye, an active dye, an insoluble azo pigment or a cationic dye, and carrying out pre-treatment; (3) adding protease into the waste textiles treated by the step (2), and carrying out selective degradation on the protein fibers; and (4) carrying out solid-liquid separation on a substance treated by the step (3); carrying out ultra-filtration separation on the protease in a degraded solution and reutilizing, wherein a degraded product is used for producing relative products; and physically recycling the residual solid textiles.

The invention relates to bio-enzyme gel breaker and applications thereof. The bio-enzyme gel breaker is an aqueous solution of beta-mannanase, alpha-galactosidase, and a cross-linking agent. According to an application method, by volume, 80 to 120 parts of a fracturing fluid base solution is mixed with 5 to 10 parts of the bio-enzyme gel breaker, and after gel forming, an obtained mixture is taken as a fracturing fluid. According to applications, galactosidase is used for removing a part of galactose residues on the side chains of galactomannan, so that mannose glycosidic bonds on the main chain of galactomannans are exposed, and then degradation effect of mannanase is adopted for selective degradation of galactomannan. Combination of the above two enzymes is capable of realizing high-efficiency rapid gel breaking of the fracturing fluid, reducing molecular weight of gel breaking products greatly, and reducing reservoir damage.

The invention relates to an enzyme treatment and recycling method for cellulosic fibers in waste textiles. The provided method aims to effectively realize the recycling of the cellulosic fibers in the waste textiles. According to the technical scheme provided by the invention, the enzyme treatment and recycling method for the cellulosic fibers in the waste textiles sequentially comprises the following steps: (1) qualitatively determining the variety of fibers in the waste textiles and the variety of dyes; (2) adding oxidordeuctase into dyed textiles which are directly treated by a direct dye, an active dye, an insoluble azo pigment or a cationic dye, and carrying out pre-treatment; (3) adding cellulase into the waste textiles treated by the step (2) and carrying out selective degradation on the cellulosic fibers; and (4) carrying out solid-liquid separation on a substance treated by the step (3); carrying out ultra-filtration separation on the cellulase in a degraded solution and reutilizing, wherein a degraded product is used for sugar fermentation to produce relative products; and physically recycling the residual solid textiles.