61results about How to "Reduce negative charge" patented technology

A process and a memory architecture for operating a charge trapping memory cell is provided. The method for operating the memory cell includes establishing a high threshold state in the memory cell by injecting negative charge into the charge trapping structure to set a high state threshold. The method includes using a self-converging biasing procedure to establish a low threshold state for the memory cell by reducing the negative charge in the charge trapping structure to set the threshold voltage for the cell to a low threshold state. The negative charge is reduced in the memory cell by applying a bias procedure including at least one bias pulse. The bias pulse balances charge flow into and out of the charge trapping layer to achieve self-convergence on a desired threshold level. Thereby, an over-erase condition is avoided.

The invention relates to modified tussah silk fabric with functionalized nanometer chitosan and nanometer titanium dioxide. The modified tussah silk fabric is prepared by the steps in sequence: weaving the tussah silk fabric by utilizing tussah filament, preparing finishing liquor and finishing tussah silk fabric; and the technical problems that the existing textile materials in the modification technology can not effectively improve the properties that the tussah silk fabric has damage to the environment, is easy to wrinkle, not anti-bacterial and easy to shrink, has poor dyeing property, poor comfortableness and function, and the like can be solved, the comprehensive properties that the tussah silk fabric is anti-wrinkle, soft, anti-bacterial, shrink-proof, self-cleaning and ultraviolet ray-resistant, as well as the adsorption efficiency of dye, and the like can be improved and enhanced, and the tussah silk fabric has the technical benefits of being lower in preparation cost, simple in process, environment-friendly and easy to realize, etc.

The invention discloses a high-throughput polyamide nanofiltration composite membrane and a preparation method thereof, which belong to the field of polymeric membrane materials. The composite membrane is prepared by the interfacial polymerization reaction between 5-(N-sulfonamido)isophthaloyl dichloride or a mixture of 5-(N-sulfonamido)isophthaloyl dichloride and 1,3,5-trimesoyl chloride and piperazine monomer, and can be widely used in a water softening process for removing bivalent cations such as Ca<2+> and Mg<2+>. The high-throughput polyamide nanofiltration composite membrane is structurally provided with an ultrathin (10nm) release layer, surface charge are low in electronegativity, the membrane surface property is smooth and hydrophilic, high throughput is shown in terms of properties, the high-throughput polyamide nanofiltration composite membrane has an excellent trapping effect on bivalent and polyvalent cations and good pollution resistance, and the high-throughput polyamide nanofiltration composite membrane can be widely applied in high-throughput domestic water purifiers, sea water desalination, brackish water pretreatment, removal of COD (chemical oxygen demand) suchas dye molecules and phenol molecules in wastewater, separation of dye/salt and material separation and concentration processes in pharmaceutical and food industries.

The invention discloses a cadmium-arsenic composite polluted soil remediation agent, which comprises the following raw materials in parts by weight: 0-10 parts of hematite; 20-30 parts of ferrous sulfate; 10 parts of manganese dioxide; 15-20 parts of fly ash; 10-15 parts of quicklime; 10-15 parts of sepiolite; 10-15 parts of calcium dihydrogen phosphate; and 0-10 parts of wollastonite. The remediation agent enables cadmium and arsenic heavy metals to form stable chemical forms through oxidation reduction, adsorption, ion exchange, precipitation or coprecipitation and the like to reduce the migration and diffusion capability of the cadmium and arsenic heavy metals in the environment, so that the ecological environment risk of the cadmium and arsenic heavy metals is reduced; and the remediation agent has the advantages of high remediation efficiency for cadmium-arsenic composite polluted soil, short remediation period, low remediation cost, easily available raw material components and simple application method, so that the agent is one of the few remediation agents in the industry that simultaneously act on yin and yang heavy metal ions.

The present invention discloses the application of RE element in cultivating aerobic sludge particle and controlling sludge expansion. During cultivating aerobic sludge particle, RE element solution of concentration below 30 mg/L is thrown into the biochemical reactor once every three days. Thus cultivated aerobic sludge particle with RE element has short forming period, large particle, low water content, high deposition rate, low SVI, high COD load and other advantages.

The invention discloses a preparing method and application of positive ionic guar gum grafted copolymer retention and filter aid, which comprises the following steps: dispersing non-purified guar gum powder in the low-carbon alcohol/water solution, aerating nitrogen, stirring evenly at indoor temperature, adding positive ionic etherifying agent solution, dripping strong-alkaline catalyst, reacting at 40-75 deg.c to obtain positive ionic guar gum, allocating into colorless transparent solution, adding triggering agent, acrylamide and vinyl cationic monomer, adding adjuvant, reacting at 10-65 deg.c for 2-24h to obtain the product.

The invention relates to a nanometer emulsion blocking agent used for drilling fluid, and a preparation method and application thereof. The nanometer emulsion blocking agent is prepared through polymerization by dispersing at least two double-bond-contained monomers into water containing an emulsifier and a co-emulsifier in an weak alkali environment under the action of a catalyst; and raw materials participating in reaction comprise, by weight, 40 to 60 parts of the double-bond-contained monomers, 2 to 6 parts of the emulsifier, 1 to 4 parts of the co-emulsifier, 0.1 to 0.5 part of the catalyst and 30 to 50 parts of the water. Accordingn to the invention, a particle size of a dispersed particle in the nanometer emulsion blocking agent is distributed in a nanoscale and is less than 500 nm, so the nanometer emulsion blocking agent has good blocking effect, cen block micropores and be casted into microcracks, and is capable of reducing pore pressure transmission, maximumly reducing differential pressure sticking and effectively inhibiting hydration dispersion of clay; the nanometer emulsion blocking agent is stable in high salinity and has the advantages of convenient use, no toxicity, no pollution and easy degradation; and the preparation method of the nanometer emulsion blocking agent has the advantages of reasonable process, mild and controllable conditions, no post treatment, low cost and benefit ratio, and facilitation to industrial production.

The invention discloses a novel azlactone-based polyamide membrane and a preparation method thereof, and belongs to the technical field of a nanofiltration membrane (loose reverse osmosis membranes).The azlactone-based polyamide membrane is formed by monomers containing azlactone groups and primary aliphatic monomers through interface polymerization reaction; the azlactone-based polyamide membrane shows the electric neutral state or the electropositivity state on a surface structure and has a smooth membrane surface; good anti-pollution performance and excellent interception effect on bivalent and multivalence cations are shown in aspects of performance; the CUT-OFF of the azlactone-based polyamide membrane is 300 to 600 Dalton. The azlactone-based polyamide membrane can be widely appliedto material separation processes such as water softening, dye/salt separation, and concentration and separation of amino acid polypeptide molecules with different molecular weights, and can also be used in the water treatment fields of sea water desalination, brackish water pretreatment and the like.

The invention relates kinds of method for intensifying filter effictiveness with filter-media modification and dynamic casting of medicine in treatment of water and sewage water, the filter-media modification and dynamic casting of medicine intensifying filter effictiveness method. This invention can be through with the steps as follows: (1) before filtering, decline negative electricity in surface of filter media, or increase modified ability of positive electricity in surface of filter media; (2) in procedure of filtering, cast medicine for intensifying filter efficiency continually. The step of (1) can germinate the particle, in surface of which contains the elements such as Iron, Manganese, Calcium, Silicon, Magnesium, Aluminum, and so on. So it increases electric potential to the surface of filter media, improves absorbability of impurity particle and makes this granule be prone to depositing in the surface of filter media. The step of (2) increases electric potential to the surface of colloidal particle in water by casting medicine for intensifying efficiency continually in filtering procedure, so that it can increase absorbability of colloidal particle in the surface of filter media. The organic association with couple of devices can increase absorbability of colloidal particle in the surface of filter media in water, and intensify removal ability of turbidity in water.

A method for recovering and purifying polyglutamic acid efficiently is disclosed, which method includes the steps of adjusting pH of a solution containing γ-PGA to neutral or slightly acidic range and filtering the solution through a plurality of filtration membranes with various molecular weight cutoffs to recover γ-PGA. Advantages of the method includes using none or minimum of organic solvent, reducing consumption of filtration membranes, reducing water volume for dilution, shortening operation time, high productivity, and obtaining various γ-PGA products with different range of molecular weight.

The present invention provides a group of novel SMA derivatives and a covalent conjugate of the derivatives and an active substance. More specifically, the present invention provides: an SMA derivative which contains (i) a styrene-maleic acid copolymer (SMA) and (ii) a side chain (b) that contains a functional group (a) selected from among —NH2, —SH, —OH, —COOH, —NH—(C═NH)—NH₂ and —C(CH₂—OH)₃ and introduced into a carboxyl group of a maleic acid residue of the SMA via an amide bond or an ester bond, and wherein when a plurality of side chain (b) is introduced into the SMA, the side chains (b) may be identical or different from each other; and a conjugate of this SMA derivative and an active substance.

The invention is a palmityl trimethyl ammonium bromide expansive soil modifier, characterized in comprising the preparing steps of: (1) at room temperature, preparing saturated lime water solution; (2) weighing the needed palmityl trimethyl ammonium bromide in the mass ratio of palmityl trimethyl ammonium bromide to dry soil = 0.5 : 99.5; (3) dissolving the palmityl trimethyl ammonium bromide in the saturated lime water solution, where it needs to notice that the dosage of the saturated lime water solution is able to completely dissolve the palmityl trimethyl ammonium bromide. And the advantages: making the soil property still able to reach the specified standard under the water influence; improving engineering property of expansive soil; unable to cause environmental pollution. And its construction method uses osmotic modification principle and fully uses multi-crack property of expansive soil and is simple and convenient.

According to the present invention, there is provided a fluorescent nucleotide represented by the formula: A-B-C,

wherein A represents a residue of natural or synthetic nucleotide, oligonucleotide, polynucleotide, or derivative thereof, and binds to B at a base moiety in said residue; B represents a divalent linking group or a single bond; and C represents a monovalent group derived from a fluorescent dye having 0 or 1 sulfonic acid group or phosphoric acid group in a molecule. The present invention provides useful fluorescent nucleotides for labeling nucleic acids, specifically, fluorescent nucleotides of which uptake ratio is high in synthetic reaction of nucleic acids.

The invention belongs to a chemical synthesis method and in particular relates to a preparation method of a polyacid-like late transition metal-organic network catalyst material. The polyacid-like late transition metal-organic network catalyst material has a (3,4,24)-connecting topological polyacid-like salt-organic compound structure, is a crystalline catalyst which is obtained by converting a late transition metal salt and an organic bridging ligand into a metal organic network under appropriate pH and temperature, and has a chemical component of [M16(HPO3)4]L3, wherein L is the organic bridging ligand, and M contains Zn, Cd, Cu, Co, Ni and the like. The polyacid-like late transition metal-organic network catalyst is a late transition metal oxygen cluster and breaks through the traditional polyacid limit; and as late transition metal ions are introduced into the catalyst, the stability, selectivity and catalytic activity of the catalyst can be effectively improved.

The invention provides a self-extinction waterborne polyurethane coating and a preparation method thereof, belonging to the field of aqueous coatings. The coating comprises a component A and a component B. The component A comprises the following components in parts by weight: 30 to 40 parts of organic silicon modified waterborne polyurethane, 10 to 20 parts of water-based hydroxyl acrylate dispersoid, 12 to 18 parts of modified silicon dioxide extinction powder, 5 to 10 parts of lignin, 2 to 5 parts of light calcium carbonate, 1 to 3 parts of halloysite, 1 to 3 parts of sericite, 4 to 8 partsof polyamide wax slurry, 0.5 to 1 part of an MA-SAS-BA copolymer dispersing agent, 0.1 to 0.2 part of triethanolamine, 0.1 to 1 part of lauryl sodium sulfate, 1 to 1.5 parts of sodium monododecyl phosphate, 2 to 6 parts of a water-based defoamer BYK024, 4 to 8 parts of a water-based leveling agent BKY346, 5 to 10 parts of propylene glycol monomethyl ether, 0.1 to 1 part of a nonionic polyurethaneassociative thickener, 10 to 20 parts of propylene glycol methyl ether acetate and 60 to 80 parts of water. The component B is a curing agent WT-2102. The self-extinction waterborne polyurethane coating disclosed by the invention is stable in property; and a film formed by the coating is stable in property and resistant to acid, alkali and solvent corrosion, and has strength, toughness and hardness meeting national standards.

The invention relates to an expansive soil modifying agent, which can reduce the swelling shrinkage, water sensitivity and dispersion of the swelling soil, falling into the technical field of geotechnical engineering. In the application of single-molecule biquaternary ammonium salt in expansive soil modification, the single-molecule biquaternary ammonium salt is composed of a first compound, and/or a second compound, wherein the first compound has the molecular formula of A1A2A3N<+>XnN<+>A4A5A6B<2->; and the second compound has the molecular formula of A1Py<+>XnPy<+>A2B<2->. The expansive soil modifying agent is formed by mixing the single-molecule biquaternary ammonium salt and water with the mass concentration of the single-molecule biquaternary ammonium salt as 0.001-0.5%. The inventive expansive soil modifying agent has good water solubility, convenient construction, and high durability, can effectively solve the swelling-shrinkage deformation problem of the expansive soil, and reduces or eliminates the bad effect of the expansive soil on the project to meet the project requirement.

The present invention provides peptides comprising a sequence of X-₆X-₅X-₄X-₃X-₂X-₁X₁PX₃X₄PX₆X₇P-GX₁₀X₁₁AX₁₃X₁₄X₁₅X₁₆LX₁₈X₁₉X₂₀X₂₁X₂₂X₂₃LX₂₅X₂₆YLX₂₉X₃₀X₃₁X₃₂ wherein the amino acids X_-6, X_-5, X_-4X_-3, X_-2, X_-1, X₁, X₃, X₄, X₆, X₇, X₁₀, X₁₁, X₁₃, X₁₄, X₁₅, X₁₆, X₁₈, X₁₉, X₂₀, X₂₁, X₂₂, X₂₅, X₂₆, X₂₉, X₃₀, X₃₁, and X₃₂ are as defined herein. The present invention further provides pharmaceutical compositions comprising the peptides and methods of using the peptides. Also provided are methods of screening a library of peptide dimers using a peptide dimer display technology.

The invention discloses an adriamycin co-drug-loading system and a preparing method and application thereof. The adriamycin co-drug-loading system comprises an adriamycin active ingredient and a targeting vector. A targeting ligand is in covalent binding with the surface of the targeting vector, small interfering RNA is carried on the targeting vector, and the targeting vector is used for inhibiting cancer gene expression. The adriamycin active ingredient accounts for 4%-8% of the co-drug-loading system by mass, the targeting ligand accounts for 1%-10% of the co-drug-loading system by mass, and the small interfering RNA accounts for 0.5%-2% of the co-drug-loading system by mass. The preparing method of the adriamycin co-drug-loading system comprises the following steps that firstly, a targeting conjugate of a folic acid ligand is prepared; secondly, a precursor of the adriamycin co-drug-loading system is prepared; thirdly, the adriamycin co-drug-loading system is prepared. The adriamycin co-drug-loading system is good in targeting performance, high in anti-cancer activity, low in toxicity, not likely to cause drug resistance and especially suitable for preparing targeting solid tumor resisting drugs.

The invention relates to a chemico-mechanical polishing solution, in particular to the chemico-mechanical polishing solution for monox dielectric materials. The chemico-mechanical polishing solution can be effectively applied to the monox dielectric materials in a semiconductor. The chemico-mechanical polishing solution for the monox dielectric materials contains oxide polishing particles, salt components, a chelating agent, a pH conditioning agent and a water-based medium, wherein the chemico-mechanical polishing solution comprises the following components in percentage by weight: 0.2-50wt% of the oxide polishing particles, 0.1-5wt% of the salt components, 0.05-5wt% of the chelating agent and the balance of the pH conditioning agent and the water-based medium with total weight of the chemico-mechanical polishing solution serving as a standard, a general formula of the salt components is MXn, the M is a metallic element, the X is a halogen, and the n is equal to 1,2 or 3. The chemico-mechanical polishing solution greatly improves a removing rate of a silica film under appropriate pH conditions through unique combination of the salt components and the chelating agent.

The invention belongs to the technical field of automobile paints, and particularly relates to a water-based single-component automobile paint containing nanometer titanium dioxide and a preparation method thereof. The water-based single-component automobile paint containing the nanometer titanium dioxide mainly consists of a component A, a component B and a component C, wherein the component A mainly consists of nanometer titanium dioxide, a copolymer dispersion agent containing high-pigment affinity groups, a modified silicon dioxide solution, methyl glycol, an organosilane surfactant and water; the component B is an aliphatic polyurethane dispersion; the component C is a polyurethane associative rheological agent. An automobile paint film prepared by the water-based single-component automobile paint containing nanometer titanium dioxide is flat and bright, and has the advantages of obvious gold and yellow phases, good adhesion force, scratching-resistant property, high glossiness, and excellent aging-resistant and anti-ultraviolet properties. The water-based single-component automobile paint containing nanometer titanium dioxide has the advantages that the heat isolation effectis good, the self-cleaning and dirt-resistant properties are good, and the water-based single-component automobile paint is ideal.

The invention provides a cationic anti-collapse agent for water-based drilling fluid, a preparation method and application of the cationic anti-collapse agent. The cationic anti-collapse agent is prepared from the following raw materials by mass: 6-10 parts of acrylamide, 1.5-2.5 parts of a cationic monomer, 1-2 parts of a hydrophobic monomer, 0.3-0.5 part of modified silicon dioxide, 0.1-0.3 part of an initiator and 30-50 parts of ethanol. The invention also provides a preparation method of the cationic anti-collapse agent. The cationic anti-collapse agent for the water-based drilling fluid has the advantages that the inhibition performance is high, the shale rolling recovery rate is high, the surface wettability of shale can be reversed from liquid wettability to strong hydrophobicity, and hydration expansion of shale clay minerals is effectively inhibited.

The invention relates to a novel cement-modified arenosol additive composition, comprising the following raw materials: lime, calcium oxide, a monomolecular biquaternary ammonium salt, polyvinyl alcohol and potassium chloride, wherein the mass ratio of the lime to calcium oxide to the monomolecular biquaternary ammonium salt to polyvinyl alcohol to potassium chloride is 1 to (0.2-0.5) to (0.2-0.5) to (0.2-0.5) to (4-5). The lime, calcium oxide, the monomolecular biquaternary ammonium salt, polyvinyl alcohol and potassium chloride disclosed by the invention take an aqueous solution as a transfer medium, and are easily dissolved into water; molecules of a film agent take the interaction of static electricity as film-forming power; effective molecules of the film agent are deposited on electronegative strong hydrophilic clay particles of arenosol to form a nanoscale ultrathin film; the negative charge quantity on the soil surface is reduced; the arenosol is insensitive to water molecules; the arenosol is obviously weakened. The cement-modified arenosol additive composition reacts with the arenosol and does not generate dissolution action, so that the property of the arenosol can still achieve the established target under the effect of water, and the additive amount of cement when the arenosol is subjected to cement modification is greatly reduced.