1705 results about "Volume concentration" patented technology

The systems and methods described herein automatically detect, highlight and identify high-Z materials in volume concentrations of approximately 100 cm3 or greater utilizing single and / or dual energy sources with x-ray and neutron detectors. The methods and systems described herein are applied to the imaging of containerized cargo and cargo vehicles. Pursuant to the described systems and methods, radiation powers are orders of magnitude lower than those used in the conventional systems. By reducing the radiation power by a factor of, for example, 100 or more, the shielding requirements for the system are greatly reduced, alignment requirements can be significantly relaxed and system components can be lighter weight and more modular. Consequently, system costs are reduced.

A coating containing pigment particles and a polymer matrix is provided. The coating contains pigment particles that have a scattering coefficient with a linear or quasi-linear relationship to the pigment volume concentration of those pigment particles. The coating has improved hiding and is useful as a protective coating or an aesthetic coating on an underlying substrate. Also provided are compositions useful for preparing the coating, including covalently bonded composite particles and aqueous dispersions containing composite particles. The composite particles each contain a pigment particle with a plurality of polymer particles attached by adsorption on the outer surface of the pigment particle or by covalent bonding to the pigment particle through a coupling agent. Methods to prepare the composite particles and coating compositions containing the composite particles are also provided.

A method for gelating a co-precursor relates to an aerogel. The invention provides a method for preparing transparent silica aerogel by normal pressure drying through a co-precursor method. The method has the advantages of low cost, simple process, short production cycle, controllable reaction course and continuous production. Tetraethyl silicate and absolute ethyl alcohol are put into a container according to a proportion and stirred, and added with methyl triethoxysilane; added with water and stirred; added with hydrochloric acid to regulate the pH of the solution; added with ammonia water to regulate the pH of the system after stirring; the silica sol is kept stand still after stirring to obtain wet gel; the obtained wet gel is put into a normal hexane solution or a normal hexane solution containing the methyl triethoxysilane with volume concentration of 10%-50% for solvent exchange and aging, after being exchanged by the solution containing the methyl triethoxysilane agent, the gel is washed by the normal hexane solution to remove the methyl triethoxysilane remained on the surface of the sample, and the transparent silica aerogel is obtained by drying.

The invention relates to a method for recycling sulfur from acid gases containing hydrogen sulfide, comprising the following steps: (a) air supply; (b) acid gas pretreatment; (c) mixture; (d) primary direct catalytic oxidation; (e) primary sulfur condensation; (f) process gas reheating; (g) secondary direct catalytic oxidation; (h) secondary sulfur condensation; (i) sulfur re-separation; (j) degasification in a liquid sulfur tank; and (k) tail gas burning. When the volume concentration of H2S in the acid gases in the prior art is 1-15%, the recycle rate of sulfur can reach over 99% by the method of the invention, and the emission load of H2S in the acid gases processed by the method of the invention meets the emission requirement of Integrated Emission Standard of Air Pollutants (GB16297-1996).

The invention discloses a titanium alloy containing an antibacterial coating as well as a preparation method and application thereof. The titanium alloy deposited with nano-silver antibacterial coating on the surface is prepared by the following steps: preprocessing and sterilizing the surface of titanium alloy; then soaking the titanium alloy in a dopamine hydrochloride solution with mass-volume concentration of 1-10mg / mL for 12-36h to obtain titanium alloy deposited with a polydopamine thin film layer on the surface; and finally soaking the titanium alloy in a silver nitrate solution which is 5-100mmol / L in concentration for 12-36h. According to the titanium alloy disclosed by the invention, the titanium alloy is connected to silver nanoparticles by virtue of adhesion from self-polymerization of dopamine and adsorbed silver ions are reduced into nano-silver in situ through weak reducibility of the dopamine. Because of broad-spectrum antibacterial capacity of the nano-silver, an excellent antibacterial effect can be achieved with relatively low effect concentration. The invention provides new thinking for antibacterial modification of the titanium alloy, and can effectively promote application of a titanium alloy implant material in the fields of bone tissue repair and regeneration.

A method for characterizing a coating comprising a pigment and metallic flakes, said method by directing beams of light toward a coating; measuring the reflectance of light from the coating at the specular angle; measuring the reflectance of light from the coating at one or moren on-specular angles; analyzing said measured light at the specular and non-specular angles as a function of wavelength; and determining the K / S of the pigment and the volume fraction of said metal flakes within the coating from the measurements of the specular and non-specular reflectance; wherein K is the absorption cross-section of the pigment multiplied by its volume concentration; and S is the scattering cross-section of the pigment multiplied by its volume concentration.

The invention relates to a preparation method of lithium carboxymethyl cellulose for a lithium battery, belonging to the field of natural high-polymer chemical modification. The preparation method provided by the invention comprises the following steps: dispersing sodium carboxymethyl cellulose prepared by a slurry process into an organic solvent, adding a hydrochloric acid water solution, mixing, reacting at 20-50 DEG C, removing the liquid, washing with an 80-95 vol% organic solvent, removing the liquid, baking, and pulverizing to obtain carboxymethyl cellulose acid; and dispersing the carboxymethyl cellulose acid in an organic solvent, adding an LiOH.H2O water solution, reacting at 40-60 DEG C, neutralizing with glacial acetic acid until the pH value is 6-8, washing with a 75-85% organic solvent, removing the liquid, baking, and pulverizing to obtain the lithium carboxymethyl cellulose. The preparation method can be used for obtaining lithium carboxymethyl cellulose with different degrees of substitution, different viscosities and excellent water solubility, and provides a novel water-soluble binder with low price and excellent properties, thereby enhancing the cyclical stability and discharge capacity of the lithium battery.

The invention relates to a method for preparing essential oils. The method comprises the following steps: taking and smashing raw materials; placing the smashed raw materials in an extraction kettle; carrying out supercritical extraction by taking a supercritical carbon dioxide fluid as an extractive solvent and taking alcohol with the volume concentration of 55 to 65 percent as an entrainer, wherein the extraction temperature is 25 to 38 DEG C, the extraction pressure is 15 to 22 MPa, the extraction time is 1.5 to 3 h, the ratio between the quality (Kg) of the raw materials and the volume (L) of the extraction kettle is 0.2 to 0.5 : 1, and the ratio between dose (L) of the entrainer and the volume (L) of the extraction kettle is 0.05 to 0.07 : 1; separating with a separation kettle to obtain an extract; placing the extract obtained through extraction in a molecular still; carrying out molecular distillation under the conditions of 0.3 to 0.5 Pa, 160 to 180 DEG C; and collecting to obtain a corresponding essential oil. The method can be used for extracting essential oils from various plants, so that compared with the prior art, the invention has the advantages of high essential oil yield and high contents.

Latex paint formulations that contain N-n-butyl ethanolamine (BAE) as the neutralizing agent and methods for their use are disclosed. BAE provides paint formulations that have low odor, increased open time, and reduced volatile organic compounds (VOC). BAE also aids in pigment dispersion so less pigment dispersant is required for paint formulations in which the pigment volume concentration (PVC) of the formulation is 38% to 80%.

The invention discloses a tail gas buffer dilution treatment method for safe emission of hydrogen from a fuel cell vehicle and a device thereof. The device comprises a hydrogen buffer, a flow control valve, a draining valve, a flame arrester, an earth terminal, an emergency hydrogen exhaust valve, a hydrogen sensor and a control module. The pulse hydrogen emitted from an anode side of the fuel cell is firstly buffered by the buffer, and a small stream of air introduced from an air path emitted from the cathode side dilutes and sweeps the hydrogen in the buffer; then the diluted hydrogen emitted from the buffer and the gas from a main air pipeline are mixed, thus the volume concentration of the tail hydrogen emitted from the fuel cell vehicle is controlled below the explosion limit concentration 4%, and the purified water discharged from a condenser can be recycled. The tail gas buffer dilution treatment device utilizes the techniques of self-diffusion, multi-tube pass buffer, air mixing and exchange, expansion, condensation and the like to buffer and dilute the hydrogen-containing tail gas emitted from the fuel cell vehicle and separate the water and gas in the hydrogen-containing tail gas, thus eliminating the possible fire hazard and ensuring the safe running of the fuel cell vehicle.

Provided is a method for enhancing chemical etching through femtosecond laser to manufacture a large-scale micro-lens array. The method includes: choosing hard materials serving as femtosecond laser action targets, and generating a light destroying area at the center of the target with the femtosecond laser acting focus as the center due to the special machining characteristics of the femtosecond laser according to the shape of a micro-lens array needing machining by controlling the target moving speed of a precise machining platform and enabling the femtosecond laser to act for 100-1000 pulse counts on the surface of the target, wherein the impulse frequency is 1KHz; performing chemical corrosion on the target processed by the femtosecond laser through hydrofluoric acid solution with the volume concentration of 1% to 10%, wherein the chemical corrosion is assisted by ultrasonic wave water bath heating, the heating temperature is 30-80 DEG C, and the heating time is 40-80 minutes; and thoroughly cleaning the corroded target in deionized water, therefore a template finished product of the large-scale micro-lens array is obtained. The method for enhancing chemical etching through femtosecond laser to manufacture the large-scale micro-lens array combines the chemical etching technology and finally achieves low-cost and high-efficiency volume production of the large-scale micro-lens array.

The invention discloses a method for preparing a grapheme three-dimensional entity with a hydrothermal reduction method. The method comprises the following steps of: mixing oxidized grapheme with water; stirring or ultrasonically dispersing to form an oxidized grapheme solution with the mass volume concentration between 1 mg / ml and 10 mg / ml; adding an alkali solution to adjust the pH value of the solution to 8-13; pouring the solution into a hydrothermal reaction kettle; putting the reaction kettle into a drying oven and raising the temperature to 100-400 DEG C for reacting for 3-48 hours; cooling; and taking the product out and drying to obtain the grapheme three-dimensional entity. The grapheme entity prepared with the method has a smooth surface, high density and high electric conductivity. The preparation method is convenient to operate, and is simple and practical.

A two-stage conversion process for high-concentration CO whose volume concentration is greater than 50% includes such steps as pre-heating to 240+ / -20 deg.C, steam saturating, stage-one sulfur-resistant wide-temp conversion by one or two segments for 1-2 s while recovering afterheat to decrease its volume concentration to 46.1% or less, and stage-two sulfur-resistant wide-temp conversion at 180-260 deg.C for 2-2.5 S while recovering residual heat to decrease its volume concentration to 0.3-3%.

The invention discloses a preparation method of a hydroxyapatite nano-rod, which adopts an oleic acid-ethanol-water phase transfer system with low cost to prepare the hydroxyapatite nano-rod with uniform size, controllable appearance and nano-scale. The hydroxyapatite nano-rod is prepared by the steps as follows: a. firstly, the oleic acid, ethanol and an additive are mixed; b. secondly, a calcium salt aqueous solution is dispersed into the oleic acid-ethanol mixed medium; the volume content of the calcium salt aqueous solution in a final mixed solution is 5 percent to 15 percent; the mass volume concentration of the calcium salt is 0.1 percent to 10 percent; c. then,a phosphate aqueous solution is added and mixed at room temperature; the mass volume concentration of the phosphate is 0.1 percent to 10 percent; d. the mixture generated from step c reacts in a reactor between 80 DEG C and 200 DEG C; e. centrifugation is carried out to remove a supernatant fluid and the obtained object is washed by a cleaning solvent and then dried so as to obtain the hydroxyapatite nano-rod. The preparation method is characterized by low production cost and comparatively high product quality, thus being hopeful to be applied in the medical field.

Disclosed is a method for preparing quasi-periodic micro-lens arrays through femtosecond laser wet etching. The method comprises that the velocity of a target material moved by an accurate processing platform is controlled according to the individual average size of quasi-periodic micro lenses needed to be processed, femtosecond lasers act for one pulse on the target material surface at a fixed interval, and a light damage area is produced on the target material with the acting focus of each femtosecond laser pulse serving as a center; chemical corrosion is performed on the target material processed by the femtosecond lasers through a hydrofluoric acid solution with a volume concentration in a range of 1% to 10%, and ultrasonic water-bath heating is assisted; and the corroded target material is cleaned thoroughly in deionized water to obtain a template finished product of mass quasi-periodic micro-lens arrays. The method has the advantages of being high in efficiency, low in cost, controllable in micro-lens individual shape size and the like, and negative effects of air breakdown effects of laser focusing, periodic light field coupling stacking effects and the like generated in a dodging process can be prevented effectively.

The invention discloses a method for melting copper by using waste copper and concentrate of copper sulfide as raw materials. The method comprises the following steps of: in a mass ratio of the copper content of waste copper to the copper content of the concentrate of copper sulfide of 1:1.3-10, mixing the waste copper and the concentrate of copper sulfide, adding a raw material containing silicon dioxide into the mixture, recycling, continuously putting the mixture into a melting pond, adding fuel and controlling the temperature of the melt to be between 1,100 and 1,300 DEG C, charging oxygen-enriched air, of which the volume concentration is 23 to 85 percent, in the melting pond, and stirring and melting the materials in an oxidizing atmosphere in the melting pond until slag and copper matte are separated by melting; transferring the separated copper matte to an air refining procedure for air refining to obtain raw copper products; transferring the slag to a common electric furnace for melting to further lower the copper content of the slag to below 0.5 percent, and performing water quenching of the slag; and transferring smoke to an acid-making procedure for preparing sulfuric acid. By the method, a large amount of waste copper can be treated, and simultaneously due to the adoption of the waste copper, the slag type of the concentrate of copper sulfide in melting is improved.

The invention discloses a method for preparing an astaxanthin extractive from haematococcus pluvialis powder. The method comprises the following steps: (1), weighing haematococcus pluvialis powder, adding food-grade alcohol, fully and uniformly mixing to obtain a mixture as a reaction system, and extracting the reaction system for 1 to 2 hours at a room temperature in a dark place, wherein the ratio of haematococcus pluvialis powder to food-grade alcohol is 1 g / 10-20 mL, and the food-grade alcohol adopts a food-grade alcohol solution with the volume concentration of larger than or equal to 95%; (2), centrifuging after extraction is finished to respectively obtain residue and supernatant liquor; (3) replacing the haematococcus pluvialis powder obtained from the step (1) with the residue, and repeating the step (1) and the step (2) at least once in sequence; and (4), combining the supernatant liquor obtained from the step (2) and the supernatant liquor obtained from the step (3), and recovering alcohol through vacuum concentration to obtain a dark red extract, namely the astaxanthin extractive. The astaxanthin extractive, prepared by the method, has the characteristic of high content of the astaxanthin monomer.The invention discloses a method for preparing an astaxanthin extractive from haematococcus pluvialis powder. The method comprises the following steps: (1), weighing haematococcus pluvialis powder, adding food-grade alcohol, fully and uniformly mixing to obtain a mixture as a reaction system, and extracting the reaction system for 1 to 2 hours at a room temperature in a dark place, wherein the ratio of haematococcus pluvialis powder to food-grade alcohol is 1 g / 10-20 mL, and the food-grade alcohol adopts a food-grade alcohol solution with the volume concentration of larger than or equal to 95%; (2), centrifuging after extraction is finished to respectively obtain residue and supernatant liquor; (3) replacing the haematococcus pluvialis powder obtained from the step (1) with the residue, and repeating the step (1) and the step (2) at least once in sequence; and (4), combining the supernatant liquor obtained from the step (2) and the supernatant liquor obtained from the step (3), and recovering alcohol through vacuum concentration to obtain a dark red extract, namely the astaxanthin extractive. The astaxanthin extractive, prepared by the method, has the characteristic of high content of the astaxanthin monomer.

The invention discloses an environmental aerosol direct sampling gathering sample injecting device and a quantitative analysis method. The environmental aerosol direct sampling gathering sample injecting device comprises an environmental aerosol sampling module, an aerosol atomization dissolving generation module, an aerosol condensation growing up module, an aerosol number concentration gathering module and a base body gas removing module. The environmental aerosol sampling module comprises a sampling port, a sampling pump and a connection pipeline, preferably, the sampling pump is a membrane pump; the aerosol atomization dissolving generation module comprises an atomizer, a fog chamber, a drying device and a connection pipeline, the atomizer is used for atomizing a standard solution to generate fog drops, the fog room is used for removing large fog drops and the drying device is used for dissolving the fog drops output from the fog room and removing steam contained in the fog drops. Due to the mode that the environmental aerosol direct sampling gathering sample injecting device serves as an aerosol sample injection system and is used in cooperation with an ICP-MS, quality sample injection rate of an element to be measured in environmental aerosol can be measured quantitatively, and then sample injection volume flow of the environmental aerosol is divided by the quality sample injection rate to acquire the quality volume concentration of the element to be measured.

The present invention relates to an infatmul containing docetaxel and its preparation method. Said preparation can be directly used for intravenous injection. At the same time of that it is used as medicine for curing tumor disease said preparation also can provide nutrients for patient. The weight volume concentration range of docetaxel contained by said preparation is 0.1-1.0 mg / ml, and its specification is that 1-500 mg of active component docetaxel is contained. Said infatmul composition includes docetaxel, vegetable oil, phospholipids and injection water, at the same time the components of glycerin and group emulsion, etc. can be added, in which the optimum group emulsion is poloxamer 188. Besides, said invention also provides the concrete steps of its preparation method and its application in preparation of medicine for resisting tumor.

A water-based, low-emission latex paint formulation includes a vinyl acetate / ethylene (VAE) latex including a VAE resin with from 80 to 95 weight % vinyl acetate residue and from 5 to 20 weight % ethylene residue, optionally including additional monomers as well as a pigment composition including inorganic solids selected from inorganic pigments, inorganic fillers and mixtures thereof present in an amount such that the paint formulation has a pigment volume concentration (PVC) of from 25% to 85%. The formulations are suitable for eggshell and flat latex paints and exhibit surprising durability.

The invention discloses a CO2 full capture and H2S enrichment process. According to the process, a low-temperature methanol washing process and an acid gas extraction concentration process are effectively combined, and a nitrogen gas extraction system and an H2S enrichment tower are canceled, so that no nitrogen gas consumption is in a running process and the running cost of the process is reduced; finished low-pressure CO2 gas in the low-temperature methanol washing process is fully utilized to cool acid gas, so that the solubility of an MDEA (methyldiethanolamine) solution is improved, at least 5% of MDEA solution circulation volume is reduced, and the energy consumption is lowered; a tail gas washing and discharging system is not configured, no tail gas is generated in the running process, and more than 99.5% of CO2 gas in coarse synthesis gas can be recovered and turned into finished high-concentration CO2 gas, so that the full capture of the CO2 gas is achieved, the volume concentration of the H2S gas in the H2S-rich acid gas is more than 70%, and the full enrichment of the H2S gas is achieved.

The invention discloses a method and a system for monitoring flow parameters of two-phase flow. According to the invention, a two-phase flow pipeline to be monitored comprises at least one dielectric material pipe formed by dielectric material; at least one pair of electrode plates is twisted into a spiral shape in the same way along the longitudinal direction on the outer surface of the dielectric material pipe; on the outer surface of the dielectric material pipe, an upstream position and a downstream position on one side of the at least one pair of electrode plates are provided with identical capacitance sensors in the same way; when the two-phase flow flows through the dielectric material pipe, capacitance induced on the at least one pair of electrode plates and random time sequence signals induced on an upstream capacitance sensor and a downstream capacitance sensor respectively are detected; and the volume concentration of a working-medium phase in the two-phase flow and the flow velocity of the two-phase flow are calculated according to the detected signals, and then the mass flow rate of the working-medium phase in the two-phase flow can be figured out.

The invention provides an extractive containing total meroterpenoid of psidium guajave dialdehyde, and a preparation method and application thereof. The preparation method comprises the following steps of: (1), removing impurities from psidium guajave leaves, shearing the psidium guajave leaves, and refluxing and extracting for 1-4 times by using ethanol; and mixing extracted solutions, filtering, decompressing and concentrating to obtain a concentrated solution of the psidium guajave leaves; (2), enabling the concentrated solution to flow through a macro-porous adsorption resin chromatographic column, and eluting by using water at first, then, eluting by using low-concentration ethanol with the volume concentration of 5-20%, and finally, eluting by using high-concentration ethanol with the volume concentration of 40-100%, and collecting a high-concentration ethanol eluant; and (3), decompressing, concentrating and drying the collected eluant so as to obtain the extractive containing the total meroterpenoid of psidium guajave dialdehyde. The method disclosed by the invention is simple in preparation process; the content of the extractive can be up to 30-80%; compared with extraction by directly using an organic solvent, the yield and the content are higher; the process is also more economic and environment-friendly; and the extractive disclosed by the invention can be used for preparing medicines and health-care products for preventing and curing type II diabetes, anti-tumor microorganisms and anti-viral microorganisms.

An object of the present invention is to provide an adsorbent suitable as an adsorbent for a canister which is capable of reducing an amount of evaporated fuel gas released into the atmosphere even where a motor vehicle is allowed to park for a prolonged period of time, a process for producing the adsorbent as well as a canister using the adsorbent and a method for using the canister. The above object can be accomplished by an adsorbent in which an integrated volume of pores having an average diameter of 3,000 to 100,000 nm as measured with a mercury porosimeter is 6.5 mL / dl or more and an equilibrium adsorption as measured in an n-butane volume concentration of 2,000 ppm is 0.16 g / dL or more, a process for producing the adsorbent, as well as a canister and a method for using the canister.

The invention discloses an image method measuring device and method for gas-liquid two-phase flow in pipelines. The image method measuring method is characterized by comprising the steps of using a light source to light liquid drop to be tested through a transparent pipeline or a window, using a laser light source to light the liquid film level, using a telecentric lens and a CCD or CMOS image sensor to image liquid drop or liquid film in an area to be tested, comparing the out-of-focus blur radius of one single liquid drop image with the allowed confusion circle size of a measuring system to remove liquid drop images out of a camera lens focus depth range, processing an image of movable liquid drop in the focus depth range to extract the particle size, the speed and the direction, carrying out statistics on a lot of liquid drop to obtain the particle size distribution in the area to be tested, the speed distribution in the area to be tested, the average volume concentration in a statistic period in the area to be tested and the average volume flow rate in the statistic period in the area to be tested, and determining the thickness of the liquid film according to the distance between the liquid level of the liquid film image and the pipe wall. The image method measuring method has the advantages of only using one set of system to achieve the purpose of simultaneously measuring multiple parameters of the gas-liquid two-phase flow in the pipelines, simplifying the measuring system and reducing measuring cost.

The invention discloses a formaldehyde-free animal specimen fixed liquid and a preparation method thereof, the formaldehyde-free animal specimen fixed liquid includes the following components: a biocide mildewcide, a protein denaturant, a polyol moisturizing agent and balance of water, and if the biocide mildewcide is in solid state, the mass concentration of the biocide mildewcide is 5-20 g / L, if the biocide mildewcide is liquid, the volume concentration of the biocide mildewcide is 1-2%; the volume concentration of the protein denaturant is 5%-40%; and the volume concentration of the polyol moisturizing agent is 2% to 10%. The formaldehyde-free animal specimen fixed liquid does not contain formaldehyde, and is non-volatile, and harmless to the human body; a fresh animal organ is washed with normal saline, and stored in the fixed liquid, a year later, the organ is not corrupted, free of mildew spot, and free of obvious color and shape change, the fixed liquid color has no obvious change, and the storage effect is good.

The invention discloses a method for improving a producible oil index by use of starch wastewater. The method comprises the following steps: performing starch wastewater pretreatment, namely regulating the PH value of starch wastewater to 6.0-8.0; determining volumetric concentrations of a nitrogen source and a phosphorus source, wherein the volumetric concentrations of the nitrogen source and the phosphorus source are 0.2%-0.5% and 0.01%-0.03% respectively; determining the air injection allocation quantity, wherein the air injection allocation quantity is that the volume rate of air to the starch wastewater is (5-10):1; determining the injection quantity of the starch wastewater, wherein the injection quantity of the starch wastewater is 0.5PV-1.0PV; tracking and analyzing a field test and a field test result. The method is simple in construction process, is capable of effectively reducing the cost of improving the producible oil index by use of microorganisms and avoiding environment pollution caused by discharge of the starch wastewater and thus can be widely applied to a field test of improving the producible oil index.

The invention discloses a method for preparing three-dimensional silk fibroin porous scaffold material, and relates to the field of biomaterial, in particular to the field of tissue engineering scaffolds. The method comprises: putting silk fibroin water solution with the volume concentration of 2-50wt% into a container, and adding sodium chloride into the silk fibroin water solution at 20-80 DEG C under continuous stirring, wherein the ratio between the mass (unit: gram) of sodium chloride granules and the volume (unit: ml) of silk fibroin solution is 1-20:1; after gelatinating, standing and precipitating the silk fibroin solution, taking out the precipitate to be continuously stirred and evenly mixed; then, putting the precipitate into a mould with the needed shape to be dried; finally, washing off the sodium chloride in the scaffold by distilled water, and obtaining the silk fibroin porous scaffold material having three-dimensional porous structure. No organic solvent is used in themethod, the method is simple and efficient, and the prepared silk fibroin porous scaffold has controllable porosity factor and pore size, highly communicated pore structure as well as degradability.

The invention relates to a debris flow yield stress and maximum accumulation thickness calculation method, and belongs to the field of debris flow prevention and control engineering and water conservancy project. The debris flow yield stress and maximum accumulation thickness calculation method has the technical scheme that the equivalent clay mineral percent P in the debris flow body is determined according to the existing debris flow survey, and the equivalent clay mineral percent P in the flow area is set to be unchanged; according to the debris flow volume-weight value of the debris flow in the current time at different frequencies or the debris flow volume-weight value in the adjacent flow areas, the debris flow volume concentration value C0 is obtained through calculation; then, according to the particle grading values Cc and Dv, the equivalent clay mineral percent P calculated in the former step is used for calculation to obtain the debris flow yield stress tao and the maximum accumulation thickness H at different frequencies or in the adjacent flow areas. The method provided by the invention has the advantages that the yield stress and the maximum accumulation thickness of the debris flow occurring at the different frequency or in the adjacent flow areas can be more accurately calculated, and effective technical support is provided for debris flow hazard evaluation and prevention.

The invention discloses a hexafluoroethane purification method which comprises the following steps: rectifying a hexafluoroethane raw material under the conditions of (-70)-(-35) DEG C and 0.1-1 MPa; performing low-temperature adsorption on the rectified hexafluoroethane raw material under the temperature conditions of (-100)-(-70) DEG C; and performing pressurized adsorption on the hexafluoroethane raw material after low-temperature adsorption under the pressure conditions of 0.5-1.5 MPa, thus obtaining the hexafluoroethane product, wherein the CO2 volume concentration of the hexafluoroethane product is no more than 0.5 ppm, and the H2O volume concentration is no more than 1 ppm. According to the invention, the problem that potential safety hazard is caused due to insufficient CO2 and H2O removal depth and introduction of anhydrous HCl in hexafluoroethane is solved, the energy consumption is reduced, and the adsorption effect of adsorbent is enhanced; and the purity of the hexafluoroethane product is up to 99.9995% or above, thus meeting the requirements for electronic specific gas in the semiconductor and micro-electronics industry.