921results about How to "Low biological toxicity" patented technology

The invention relates to a multifunctional double-layer core-shell structure magnetic nano particle. In the invention, a magnetic nano particle with a particle size of 1-300 nm is used as a core and coated with a double-layer shell consisting of a SiO2 layer with a thickness of 1-200 nm and a hydrolyzed silane coupling agent layer is 1-100 nm thick and comprises one or more multifunctional groups; the particle size and the shell layer thickness can be controlled through regulating the volumes, the weight ratios and the reaction time of the magnetic core, a silicon dioxide precursor, a silane coupling agent and a catalyst in a preparation process; the total particle size of the nano particle can be as small as 5-50 nm and as large as 700-800 nm; the nano particle can have superparamagnetism, paramagnetism and ferromagnetism according to the change of the magnetic core particle size; and one or more bioactive molecules can be connected into the shell layer of the magnetic nano particle or to the surface of the shell layer through a chemical method or a physical method. The invention also provides a preparation method of the multifunctional double-layer core-shell structure magnetic nano particle and application thereof. The particle preparation method has the advantages of simplicity, moderate condition, low cost and easy realization of industrial production. The nano particle can obtain different functions through connecting different bioactive molecules and can be applied to the fields of protein enrichment, biological detection, separation and purification, targeted drug carriers, cell imaging and medical imaging.

The invention belongs to the field of water treatment, and relates to a method for strengthening the activity of anaerobic ammoxidized microorganisms through polyvinyl alcohol-sodium alginate-activated carbon embedment. The method comprises the following steps of: soaking activated carbon in anaerobic ammoxidized basic inorganic salt solution, and preparing an embedding medium by using polyvinyl alcohol, sodium alginate and the activated carbon into in a proportion; and uniformly mixing treated anaerobic ammoxidized sludge and the embedding medium in a volume ratio to obtain immobilized balls, and culturing to obtain the anaerobic ammoxidized microorganisms steadily coupled on the activated carbon. The invention aims at wastewater with low carbon-nitrogen ratio, and can provide a method for embedding the anaerobic ammoxidized sludge by using the sodium alginate and the polyvinyl alcohol as carriers and the activated carbon as a strengthening agent, and a technology for strengthening the activity of the anaerobic ammoxidized microorganisms and enabling the anaerobic ammoxidized microorganisms to resist the influence of adverse environment. By the method, sewage plants can run more steadily for a long time, and the conditions of actual operation management of the sewage plants are met.

The invention relates to a method for degrading organic pollutants in water by gradient ozone catalytic oxidation, and relates to a gradient ozone catalytic oxidation combination method for degrading organic pollutants in water. By the method, the problem that the conventional advanced oxidation technology has defects during individual use, the problem that the organic pollutants in the water cannot be removed efficiently, the problem that the influence of the pH value and temperature of the water on the method is large, and the problem that high-toxicity byproducts are formed are solved. In the method, water treatment is realized by combining two or three of a process for treating O3 individually, an enhanced catalytic oxidation process for O3 and an O3/ultraviolet (UV) process sequentially. By the reasonable optimizing and gradient combination of the three treatment modes, the method is suitable for wide pH values and a wide temperature range, the pollutants with intermediate toxicity are controlled to be formed, the toxicity of the pollutants is reduced, the pollutants in the water is degraded efficiently and completely, and the content of oxidative species in effluent is controlled. An efficient oxidation treatment effect is kept at low temperature, and the generation of bromate, nitroso dimethylamine, chlorate, perchlorate, iodate and periodate can be controlled greatly.

The invention relates to a polyamine strong inhibitor for a drilling fluid. The polyamine strong inhibitor is prepared through the following step that: an amine compound and an epoxy compound are subjected to a reaction at a temperature of 90-110 DEG C in the presence of an alkali metal catalyst to synthesize the polyamine strong inhibitor for the drilling fluid, wherein the amine compound is polyether amine, alkyl amine, ether amine, tetraethylenepentamine, pentaethylenehexamine or polyethylene polyamine, and the epoxy compound is propylene oxide or ethylene oxide. According to the present invention, based on high temperature strong water sensitivity easy-instability stratum, special molecular structure design is adopted, such that the inhibitor has strong inhibition, and mud making of clay and hydration expansion of shale can be inhibited; and the inhibitor provides a stabilization effect for dynamic cutting force when the Xuanhua bentonite addition amount is up to 30%, wherein a debris rolling recovery rate can be more than 90%, a 8 h shale linear expansion rate is less than or equal to 10%, a temperature resistance performance is more than or equal to 180 DEG C, biological toxicity is low, and a LC50 value is more than 38010 mg/L.

The invention discloses a method for producing tyrosol and hydroxytyrosol through heterologous metabolic pathways, wherein metabolic pathways for producing hydroxytyrosol are introduced into hosts forproducing the hydroxytyrosol; more specifically, the method comprises the following steps: producing tyrosol by efficiently expressing aminotransferase, ketoacid decarboxylase and alcohol dehydrogenase in the hosts, then introducing 4-hydroxyphenylacetate hydroxylase to produce the hydroxytyrosol. Genes coded by the enzymes are constructed on an expression plasmid or integrated to a genome. Through the method, production hosts capable of producing the hydroxytyrosol by using glucose, glycerinum and tyrosine can be prepared by introducing the genes coded by the enzymes to the hosts; meanwhile,the invention also discloses a biphasic cultivation method, so that the production of the hydroxytyrosol is more efficient.

The invention relates to a medical catheter and a method for forming an antibacterial hydrophilic coating on the surface of the medical catheter. The method includes the following steps of preparing graphene oxide dispersoid, dissolving hydrophilic polymers and cellulose ester in organic solvent to form a hydrophilic macromolecular solution, adding the hydrophilic macromolecular solution to the graphene oxide dispersoid in the stirring process to form an antibacterial hydrophilic macromolecular solution, soaking the catheter in a coupling agent solution after conducting surface processing on the catheter so that the surface of the catheter can be dip-coated with a coupling agent layer, soaking the catheter coated with the coupling agent layer in the antibacterial hydrophilic macromolecular solution, and preparing the medical catheter with the antibacterial hydrophilic coating after the catheter is taken out, dried and solidified. Due to the fact that the antibacterial hydrophilic coating is formed on the surface of the catheter, the coating contains graphene oxide, other hydrophilic macromolecules and other components, the catheter can have excellent antibacterial and bacteriostatic capacity, the contact angle of the catheter and water is reduced, and the surface of the catheter can have the ultra-strong lubrication effect and the bacteriostatic effect at the same time.

The invention relates to a method for preparation of a hydroxyapatite nanorod and a nanowire by a hydrothermal process. The method includes: adding a water soluble calcium salt solution into a riboflavin sodium phosphate solution at a rate of 3-50ml/min, adjusting the pH of the obtained mixed solution to 8-12 or 4-6, then leaving the solution to undergo a hydrothermal reaction at 100-200DEG C for 1-48h, carrying out separation, washing and drying the precipitate, thus obtaining the hydroxyapatite nanorod and nanowire.

The invention provides a fluorescent probe represented by the formula (I), wherein R1 and R2 are independently selected from H or an aromatic vinyl group, and at least one of R1 and R2 is the aromatic vinyl group; R3 is selected from H, F, Cl, Br, OH, OCH3, N(CH3)2 or C1-C6 alkyl; and R4 is selected from C1-C6 alkyl. Compared with the prior art, because the fluorescent probe provided by the invention has a relatively large electronic conjugated system and plane, the intensity of the intramolecular charge transfer effect can affect the molecular fluorescence emission intensity; when the fluorescent probe and the G-quadruplex generate a specific action, the flexibility of intramolecular rotatable double bonds is restricted, the intramolecular charge transfer effect is enhanced, and the fluorescence is also enhanced significantly; moreover, the fluorescent probe provided by the invention has the advantages of low biotoxicity, phototoxicity and photobleaching property, good light stability, good water solubility and good cell membrane permeability.

The invention relates to a preparation method of transition metal doped carbon fluorescent quantum dots. According to the method, a metal chelator and transition metal salt are dissolved in an organicphase and water which are incompatible with each other, then, a heating reaction is conducted, concentration and purification are performed after the reaction, and transition metal doped carbon fluorescent quantum dots with different solubility are prepared. The method is convenient to operate, doping of carbon fluorescent quantum dots with metal ions can be realized without harsh reaction conditions or large instruments. The obtained carbon dots have multiple different characteristics according to different types of doping metal ions and different solvents. The prepared carbon dots have great application value in preparation of bio-labeling sensing and medical imaging, photoelectric and light-emitting devices and the like due to these characteristics.

The invention discloses a nano-silver porous silicone rubber/polyurethane-containing double-layer artificial skin and a preparation method thereof. The nano-silver porous silicone rubber/polyurethane-containing double-layer artificial skin is characterized in that the artificial skin contains a dermis and epidermis double-layer structure; a dermis layer is prepared from loose porous polyurethane; an epidermis layer is prepared from antibacterial agent-containing silicone rubber. A preparation method of the dermis layer comprises the following steps: dissolving the polyurethane, adding a pore-foaming agent, defoaming, carrying out curtain coating so as to form a film, volatilizing a solvent, soaking so as to leach out the pore-foaming agent, and drying so as to obtain a porous polyurethane film. A preparation method of the epidermis layer comprises the following steps: dissolving a silicone rubber precursor, carrying out ultrasonic dispersion on a nano-silver solution, adding the pore-foaming agent, defoaming, carrying out blade coating or curtain coating so as to form a film, volatilizing a solvent, curing so as to obtain an embryonic film, soaking so as to leach out the pore-foaming agent, and drying so as to obtain a silicone rubber microporous film. The preparation method of the double-layer artificial skin comprises the following steps: coating the polyurethane film with polyvinyl alcohol, acid liquor and a crosslinking agent, then covering the polyurethane film by using the silicone rubber film, volatilizing a solvent, and carrying out heat treatment so as to obtain the double-layer artificial skin. The nano-silver porous silicone rubber/polyurethane-containing double-layer artificial skin has the effects of water resistance, air permeability, bacterial inhibition, virus killing and effective absorption of hydrops.

The invention provides a method for batch green synthesis of nitrogen and phosphorus doped fluorescent carbon dots, wherein the method comprises the following steps: a first step, adopting a high-boiling-point polar organic solvent as a reaction medium, wherein the boiling point of the high-boiling-point polar organic solvent is greater than 180 DEG C; a second step, adopting organic small molecules as a carbon dot precursor, and adopting an auxiliary combination synthesis reagent; a third step, by a solvothermal reaction, mixing and dissolving the carbon dot precursor, phosphoric acid and the auxiliary combination synthesis reagent in the high-boiling-point polar organic solvent, controlling the reaction temperature and the reaction time, and preparing nitrogen and phosphorus doped fluorescent carbon dots; and a fourth step, purifying the mixed solution after the reaction of the third step, to obtain the high-purity fluorescent carbon dots. The water-soluble carbon dots with high fluorescence quantum yield can be further prepared in batch, and the fluorescent emission wavelength of the fluorescent carbon dots is controlled by controlling the reaction temperature and the reaction material ratio; the preparation process is green and pollution-free, has no need of special equipment, has the cost reduced, and is prone to realization of batching and scaling production.

The invention provides a heavy metal contaminated soil restorative agent. The restorative agent is prepared from the following components in weight ratio: 20-30 percent of biomass charcoal, 30-50 percent of quick lime, 10-20 percent of molecular sieve, 10-20 percent of sodium bentonite, 1-10 percent of polyepoxysuccinic acid and 1-10 percent of sodium lignin sulfonate. A preparation method for the heavy metal contaminated soil restorative agent comprises the following steps: firstly, mixing the biomass charcoal, quick lime, molecular sieve, sodium lignin sulfonate and sodium bentonite in mass ratio to obtain a mixture; and then, adding the polyepoxysuccinic acid into the mixture in mass ratio to stir and uniformly mix, thereby obtaining the prepared soil restorative agent. The prepared soil restorative agent has good effect in restoring the cadmium, lead and zinc compound contaminated soil.

The invention provides a heavy metal cadmium, lead and arsenic compound contaminated soil restorative agent. The heavy metal cadmium, lead and arsenic compound contaminated soil restorative agent is prepared from the following components in percentage by weight: 30-50 percent of biomass charcoal, 5-10 percent of diatomite, 5-10 percent of sodium bentonite, 5-10 percent of activated aluminum oxide, 10-20 percent of dithiocar-bamate, 5-10 percent of ethylenediaminetetraacetic acid, 5-10 percent of tartaric acid, 5-10 percent of polyacrylamide and 5-10 percent of sodium dodecyl sulfate. A preparation method for the heavy metal cadmium, lead and arsenic compound contaminated soil restorative agent comprises the following steps: mixing the biomass charcoal, diatomite, sodium bentonite, activated aluminum oxide, ethylenediaminetetraacetic acid, tartaric acid, polyacrylamide and sodium dodecyl sulfate in mass proportion to obtain a mixture; and adding the dithiocar-bamate into the mixture in corresponding mass proportion to sufficiently mix uniformly, thereby obtaining the prepared soil restorative agent. The prepared soil restorative agent has good effect in restoring the cadmium, lead and arsenic compound contaminated soil.

The invention discloses a method for treating the mixed waste water of the electroplating industry, which comprises the following steps of: firstly, reacting ferrous salt and the mixed waste water of the electroplating industry, then adding sodium hydroxide or lime, regulating the pH value to 6.5 to 7.5 and precipitating for 1.5 to 2h, wherein the concentration of the ferrous salt in the mixed waste water of the electroplating industry is 2000 to 4000mg/L; after precipitating the waste water, carrying out aerobic biochemical treatment on the obtained supernatant liquid by an aerobic biochemical treatment system filled with ceramsite with the detention time of 4 to 8h and removing the COD value and the residual cyanogen in the mixed waste water; and adding a chemical oxidant of sodium hypochlorite into the treated waste water, further oxidizing the cyanogen in the waste water, regulating the pH value of the waste water to 7 to 8.5 and precipitating again for 1.5 to 2h. The method has relatively low treatment cost, not only heavy metal and cyanide reach the standard, but also the COD value in the waste water can be obviously lowered, and the treated waste water reaches a novel discharge standard.

The invention belongs to the technical fields of preparation and application of metal optical function nano materials and in particular relates to a fluorescent silver nanocluster as well as a simple preparation method and application thereof. The fluorescent silver nanocluster is synthesized by reacting soluble silver salt with a stabilizer, wherein the fluorescent silver nanocluster has the mean particle size of more than 1.5nm and less than 2nm; the fluorescence emitted by the fluorescent silver nanocluster has the wavelength of 610nm under excitation of light with the wavelength of 510nm; the emitted fluorescence has high illumination stability. The method is readily available in raw materials, simple in process, convenient to operate, low in biotoxicity and easy to popularize and apply. The synthesized fluorescent silver nanocluster can be applied to the fields of optical imaging, biological markers, biological or chemical sensors and the like, and especially can be used for qualitative and quantitative detection on the activity of alpha-L-fucosidase.

The invention discloses a phosphorescent ionic type iridium complex probe and a preparation method and application thereof, and particularly relates to a phosphorescent iridium complex for detecting hypochlorite (ClO<->) and containing an oxime group (C=N-OH) and an application thereof. The material of the complex consists of a ring metal ligand containing an oxime group, a metal center and an N^N ligand, and the structural general formula is shown in the specification. The synthesis steps of the material are simple, the conditions are mild, and the material has very good application prospects in hypochlorite detection, cell imaging and bio-labeling.

The invention provides a method for inhibiting peroxidase activity by using fluorescent graphene quantum dots. The method comprises the following steps: (1) adding a carbon source into a certain amount of water to prepare a mixed solution, heating the solution until the moisture is completely evaporated, transferring the solution into a high pressure reactor, heating and reacting for a period of time, dissolving the product in water, regulating the pH value of the system to be neutral by using alkali liquor, purifying the product, and drying, thereby obtaining solid graphene quantum dots; and (2) dispersing the quantum dots obtained in the step (1) in secondary distilled water, taking a proper amount of quantum dot solution and enzyme solution, adding the solution into a buffer solution, adding a color developing agent and H2O2 after a period of time, uniformly shaking the mixed solution, rapidly adding the solution into a cuvette, measuring the light absorption value of the maximum absorption wavelength of the product on an ultraviolet-visible spectrophotometer, and performing blank sample control, thereby determining the relative enzyme activity. The graphene quantum dots are prepared by adopting low-price and readily available raw materials, and the method is green and environment-friendly. The structure of the enzyme can be changed by virtue of the interaction between the graphene quantum dots and zymoprotein, and regulation of the enzyme activity is realized.

The invention discloses a fluorine containing water repellent oil repellent composition and its preparation method. The composition takes a monomer, inorganic silica, an emulsifier, a solvent and water as raw materials, after the emulsification of the raw materials, the composition is obtained by initiating the polymerization under the initiator existence condition. The composition reduces the biology toxicity and permanent accumulation performance, and can substantially enhance the waterproof performance of a fluorine containing fabric waterproof oilproof agent with perfluoro alkyl carbon chain length of less than or equal to 6.

The invention relates to a dry preparation method of transition metal doped carbon fluorescent quantum dots. According to the method, a metal chelator and transition metal salt are subjected to a thermal reaction in the absence of a solvent, and the transition metal doped carbon fluorescent quantum dots are prepared with extraction, centrifugation and dialysis methods after the reaction. The method is convenient to operate, doping of carbon fluorescent quantum dots with metal ions can be realized without harsh reaction conditions or large instruments, and the obtained carbon dots have good water solubility and wider fluorescence emission ranges. The obtained carbon dots have multiple different characteristics according to different types of doping metal ions and different solvents. The prepared carbon dots have great application value in preparation of bio-labeling sensing and medical imaging, photoelectric and light-emitting devices and the like due to these characteristics.