378results about How to "Avoid decomposition" patented technology

The invention relates to a weight-losing enzyme and a preparation method thereof, and belongs to the technical field of biology, and the weight-losing enzyme comprises a fruit enzyme, a vegetable enzyme, a seed enzyme and a lotus leaf extract; the fruit enzyme is obtained by performing enzymolysis on mixed fruit pulp of apples, lemons, grapefruits and haws through pectinase, performing enzymolysis through pepsase and performing co-fermentation through bifidobacterium longum and lactobacillus acidophilus; the vegetable enzyme is obtained by performing enzymolysis on mixed vegetable pulp of wax gourd pulp, celery and spinach through pectinase, performing enzymolysis through pepsin and performing fermentation through lactobacillus plantarum and bifidobacterium adolescentis; the seed enzyme is obtained by carrying out trypsin enzymolysis on mixed powder of semen raphani and phaseolus calcaratus, then carrying out nattokinase enzymolysis and then fermenting with bifidobacterium breve; the lotus leaf extract is obtained by sequentially carrying out enzymolysis on lotus leaves through hemicellulase, snail protease and nattokinase. All the components are matched for use, so that the weight-losing food has the effects of promoting digestion, inhibiting fat absorption, regulating intestinal flora, promoting metabolism and the like, and has a good weight-losing effect.

The invention relates to a catalyst for ethylene oxide ring-opening polymerization and a preparation method thereof, and belongs to the technical field of high polymer material synthesis, and the catalyst is a composite structure based on a silicon dioxide nanoparticle loaded bimetal organic complex; a modified nitrogen-containing polydentate ligand is prepared by adopting a special method, is coordinated with metal ions through covalent bonds and is loaded on silicon dioxide nanoparticles; by utilizing the high dispersity and stability of the silicon dioxide nanoparticles and the synergistic catalytic effect of the bimetal organic complex, the catalytic effect is effectively improved, the polymerization process is accelerated, the polymerization stability is enhanced, the polymerization molecular weight is improved, and the distribution is narrow.

The invention relates to a preparation method and application of an inner-rigid outer-soft core-shell structure silicon dioxide blocking agent for marine drilling fluid, and belongs to the field of deepwater oil and gas drilling. N-vinyl-2-pyrrolidone, dimethyl diallyl ammonium chloride, acrylamide and 2-acrylamide-2-methylpropanesulfonic acid are polymerized and grafted on the surface of nano silicon dioxide to form the silicon dioxide blocking agent with a core-shell structure and a rigid inside and a soft outside; by means of rigid plugging of a nano material and deformation filling flexible plugging of a high-molecular polymer, shale micro-nano pores are efficiently plugged with rigid inside and flexible outside, so that the stability of a well wall is maintained, meanwhile, secondary generation of hydrates is effectively inhibited, and the safety and efficiency of deepwater drilling are improved; the plugging agent provided by the invention reduces the demand on a large number of thermodynamic inhibitors, not only saves the cost, but also has the characteristic of environmental protection.

The invention discloses a spherical nano aluminum oxide polishing solution for silicon carbide wafer polishing, and relates to the technical field of preparation of semiconductor silicon carbide wafer polishing materials, and the spherical nano aluminum oxide polishing solution comprises the following raw materials by weight: 0.5-55% of aluminum oxide, 0.05-25% of an oxidant, 0.1-10% of an inhibitor, 0.01-12% of a surfactant, 0.01-15% of a dispersant, 0.1-10% of a pH regulator, and the balance of high purity water. The preparation process comprises the following steps: (1) preparing materials; (2) grinding material pretreatment; (3) mixing; (4) adjusting the pH value; and (5) high-pressure homogenization. The CMP polishing solution has the characteristics of high removal rate, good suspension dispersion performance, no damage to the surface of the silicon carbide wafer, extremely low surface roughness value, long cycle service life, easiness in cleaning, good universality and the like, and is suitable for CMP polishing of semiconductor silicon carbide wafers.

The invention discloses injectable hydrogel for eye drug sustained release and a preparation method and application thereof.The method comprises the steps that a NaIO4 solution is dropwise added into a hyaluronic acid solution, after the reaction is conducted in a dark place at the room temperature, ethylene glycol is added for continuous reaction, and formylated hyaluronic acid is prepared; the preparation method comprises the following steps: adding adipic dihydrazide into a carboxymethyl cellulose solution, uniformly stirring at room temperature, adding 1-hydroxybenzotriazole and 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride, and stirring to react, so as to prepare aminated carboxymethyl cellulose; and mixing the PBS solution of aminated carboxymethyl cellulose with the PBS solution of formylated hyaluronic acid, uniformly stirring, adding a to-be-carried drug and a FeCl3 solution, and carrying out a reaction to prepare the injectable hydrogel for sustained release of the eye drug. The hydrogel is convenient to use and high in gelation rate, effectively realizes controllable release of drugs, and has a wide application prospect in the field of biological medicines.

The invention relates to the technical field of welding, in particular to a lead-free solder composition and a preparation method thereof. The composition comprises brazing filler metal and a brazing flux, wherein the brazing filler metal comprises 55 to 65 parts of copper, 30 to 40 parts of zinc, 0.5 to 1 part of silver, 0.1 to 1 part of tin, 0.1 to 0.5 part of nickel, 0.02 to 0.15 part of lanthanum, 0.03 to 0.15 part of cerium and 0.05 to 0.2 part of indium; the brazing flux comprises 18-22 parts of borax, 13-17 parts of boric acid, 25-32 parts of a potassium fluoride and potassium fluoborate compound, 3-5 parts of calcium fluoride, 12-16 parts of aluminum oxide and 8-11 parts of magnesium oxide. The lead-free solder composition does not contain toxic lead elements, pollution to the environment and the ecological system is little, the wettability, corrosion resistance, strength, stability and the like of the lead-free solder composition are improved, and the welding quality is comprehensively improved. According to the preparation method, uniform distribution and accurate control of the brazing filler metal and the brazing flux are guaranteed, stability and consistency of product quality are guaranteed, and the preparation method is easy and convenient to operate and suitable for mass production.

The invention discloses a ganoderma lucidum edgeworthia chrysantha promoting agent for promoting efficient edgeworthia chrysantha of aquilaria plants, and belongs to the technical field of edgeworthia chrysantha of aquilaria plants. The component A is prepared from the following components in parts by weight: 20 to 40 parts of aspergillus niger microbial fermentation liquor, 15 to 30 parts of verticillium fulvum microbial fermentation liquor, 10 to 15 parts of fusarium oxysporum microbial fermentation liquor, 5 to 10 parts of ganoderma lucidum extract, 6 to 8 parts of seaweed extract, 2 to 8 parts of malic acid, 3 to 6 parts of fructose, 1 to 3 parts of pectinase and 0.5 to 2 parts of cellulase. Through the synergistic effect of the component A and the component B, the agilawood formation rate and quality of agilawood are effectively improved, the synergistic effect of microorganisms stimulates the agilawood formation potential of plants, accurate regulation and control of the plant hormone xylan emulsion provide conditions for synthesis and accumulation of agilawood substances, and compared with a traditional agilawood formation method, the agilawood formation method has the advantages that the agilawood formation rate is increased, and the agilawood formation quality is improved. According to the method, the agilawood with higher quality can be obtained within shorter time, and the yield is increased.

The invention relates to the field of battery materials, in particular to a halogen-free electrolyte for a magnesium metal battery and a preparation method of the halogen-free electrolyte. The magnesium salt comprises at least one of bis (trifluoromethanesulfonyl) imide magnesium and magnesium trifluoromethanesulfonate; the additive is prepared from at least one of indole, 3-azaindole, 4-azaindole, 5-azaindole, 6-azaindole, 4-amino indole, 5-amino indole, 6-amino indole and 7-amino indole; the organic solvent comprises ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1, 3-dioxolame or 1, 3-dioxane. The preparation method comprises the following steps: sequentially adding the magnesium salt and the additive into the organic solvent, and stirring and reacting at room temperature for 1 min to 24 h to obtain the halogen-free electrolyte for the magnesium metal battery. And the prepared electrolyte has excellent performances of small overpotential, long service life and wide electrochemical window, and has a good commercial application prospect.

The invention discloses a preparation method of an iron-silicon-based composite soft magnetic powder core, which comprises the following steps: compounding and uniformly mixing iron-silicon-titanium powder and iron-silicon powder, and carrying out heat treatment in an air atmosphere; and then performing insulation coating on the surface of the magnetic powder by using a polyvinyl alcohol aqueous solution and a nano oxide, and performing compression molding and heat treatment to prepare the iron-silicon-based composite soft magnetic powder core. Compared with a conventional iron-silicon powder core, the iron-silicon-based composite soft magnetic powder core prepared through the method has the advantages that the direct-current bias performance under the condition of 100 Oe is higher than 76%, the volume loss Pcv under the conditions of 50 kHz and 100 mT is lower than 500 mW / cm < 3 >, and the loss performance is obviously improved.

The invention relates to an electrode material for lithium extraction, a preparation method of the electrode material, a lithium extraction electrode and a lithium extraction system, belongs to the field of salt lake lithium extraction, and solves at least one of the problems of fast capacity fading, relatively low overall lithium extraction efficiency and short service life of a lithium extraction electrode for an alkaline solution in the prior art. A preparation method of an electrode material for lithium extraction comprises the following steps: mixing an electrode active material with a rare earth salt solution, and forming a phosphate rare earth layer on the surface of the electrode active material in an in-situ coating manner; the electrode active material comprises lithium iron phosphate and a doped derivative thereof. When the preparation method, the obtained electrode material, the lithium extraction electrode and the lithium extraction system are applied to lithium extraction of salt lake brine, especially alkaline brine, at least one of the cycle performance, the lithium extraction efficiency and the service life is remarkably improved.

The invention provides an electrolyte, which comprises a lithium salt and an organic solvent, and the organic solvent comprises a cyclic non-coordination solvent represented by the following formula (I) # imgabs0 # (I), in the formula (I), R1, R2, R3, R4, R5, R6, R7, R8, R9 and R10 are respectively and independently selected from a hydrogen atom, a chlorine atom, a bromine atom, a fluorine atom, a C1-C3 alkyl group, a C1-C3 alkoxy group, a fluorine-substituted C1-C3 alkyl group or a fluorine-substituted C1-C3 alkoxy group. The electrolyte provided by the invention can be applied to the lithium metal secondary battery, and can significantly improve the cycle stability and safety of the battery and prolong the cycle life of the battery; meanwhile, decomposition of the coordination type solvent can be effectively inhibited, and uniform deposition of metal lithium dendrites is realized, so that the stability of the electrolyte is improved; and moreover, the high-temperature storage gas production inhibition effect is obvious.

The invention relates to the technical field of capacitor electrolyte manufacturing, in particular to an ultrahigh-conductivity capacitor electrolyte formula and a preparation method thereof.The ultrahigh-conductivity capacitor electrolyte formula comprises a main solvent, a solute and an additive, an organic solvent in the main solvent and a low-viscosity organic solvent are mixed according to a specific proportion, the dielectric property and the ion migration environment of the solvent can be effectively balanced, and the conductivity of the capacitor is improved; and a good condition is created for ion transmission. And through reasonable matching and concentration control of high-dissociation-degree salts and organic salts in solutes, sufficient dissociation and efficient transmission of ions are ensured, and the conductivity of the electrolyte is greatly improved. A plurality of additives are added according to a specific proportion and properties, the conductivity enhancing additive forms a conductive network, the electrode protection additive forms a uniform protection film on the surface of an electrode to improve the interface stability, the electrolyte stabilizing additive inhibits decomposition and oxidation reactions in a wide temperature range, and stable performance and high conductivity of the electrolyte are guaranteed through a synergistic effect.

The invention relates to a formula of a high-performance sodium-ion battery electrolyte, and aims to improve the cycle life, safety and rate capability of a sodium-ion battery. The electrolyte comprises sodium hexafluorophosphate as a sodium salt, carbonic ester as an organic solvent and a plurality of additives (fluoroethylene carbonate, bis (2, 2, 2-trifluoroethyl) carbonate, ethylene sulfate, 1, 3-allyl sultone and sodium difluoro (oxalato) borate). Through the synergistic effect of the additives, a stable positive electrode / electrolyte interface film (CEI) is formed, cation dissolution is reduced, and the sodium ion transmission performance and the high-voltage stability of the battery are improved. In a half cell assembled with a NaNi0. 4Fe0. 2Mn0. 4O2 positive electrode, when the electrolyte works in a voltage range of 2-4.2 V, the specific discharge capacity of more than 160mA. H / g is provided, and the capacity retention ratio exceeds 80% after 200 cycles at the rate of 1C.

The invention relates to the technical field of polyvinyl chloride, and discloses a wear-resistant and aging-resistant PVC (polyvinyl chloride) material.The wear-resistant and aging-resistant PVC material is characterized in that glycidyl acrylate grafted ABS is used as a compatilizer, carboxyl-terminated nitrile rubber is used as a flexibilizer and a wear-resistant modifier, and polyvinyl chloride is subjected to filling modification; the modified polyvinyl chloride can react with terminal carboxyl groups of nitrile rubber, so that nitrile rubber and polyvinyl chloride have better compatibility, and the notch impact strength and wear resistance of the PVC material are improved. The hindered phenol-lanthanum complex stabilizer contains a hindered phenol structure which can capture free radicals generated in the oxidation process, inhibit free radical chain reaction and overcome decomposition of polyvinyl chloride; meanwhile, lanthanum ions in the complex can react with hydrogen chloride generated by thermal decomposition of polyvinyl chloride, so that the phenomenon that the polyvinyl chloride is degraded by the hydrogen chloride is reduced.

The invention discloses a method for modifying hexagonal boron nitride by ozone. The method comprises the following steps: performing low-temperature heat treatment on hexagonal boron nitride, mixing with water to prepare slurry, introducing ozone for oxidation treatment, and finally modifying by using a surface modifier to obtain the modified hexagonal boron nitride. The modification method disclosed by the invention is simple, after modification, the flowability and binding property of the hexagonal boron nitride in a system are improved, and the requirements on the flowability and binding property of the hexagonal boron nitride in practical application are met.

The invention provides an iron-silicon-aluminum magnetic powder core and a preparation method and application thereof. The Fe-Si-Al magnetic powder core comprises a Fe-Si-Al magnetic powder base body and a coating layer coating the surface of Fe-Si-Al magnetic powder. And the coating layer comprises silicon dioxide and aluminum phosphate. According to the Fe-Si-Al magnetic powder core provided by the invention, the silicon dioxide and the aluminum phosphate are used as the mixed insulating coating layer, so that the resistivity of the Fe-Si-Al magnetic powder core is increased, the eddy-current loss among particles is effectively reduced, meanwhile, the maximum forming density of the material is ensured, and a relatively high saturation magnetic flux density Bs is obtained, so that a high direct-current superposition characteristic is obtained; and the aim of giving consideration to low loss and high direct current superposition characteristics is fulfilled.

The invention relates to the technical field of casting powder, in particular to special casting powder for 2520 heat-resistant stainless steel and a preparation process of the casting powder. The high-temperature-resistant ceramic comprises the following components: 30-40 parts by weight of calcium oxide, 15-20 parts by weight of aluminum oxide, 8-12 parts by weight of zirconium oxide powder, 5-10 parts by weight of silicon dioxide, 10-15 parts by weight of manganese oxide, 3-5 parts by weight of titanium dioxide, 3-5 parts by weight of calcium fluoride, 8-10 parts by weight of a stabilizer and 3-5 parts by weight of rare earth element oxide. The zirconium oxide powder is prepared from zirconium chloride and yttrium nitrate through a coprecipitation method; the stabilizer is obtained by depositing aluminum oxide and silicon dioxide on the surface of magnesium oxide; the rare earth element oxide is a mixture of cerium oxide and lanthanum oxide. A layer of aluminum oxide and silicon dioxide composite coating is deposited on the surface of magnesium oxide, a layer of compact physical barrier is formed on the surface of magnesium oxide, erosion of harmful components in slag to magnesium oxide is effectively prevented, and the corrosion resistance of magnesium oxide is remarkably improved.

The invention discloses a sodium-ion battery electrolyte as well as a preparation method and application thereof, and belongs to the technical field of battery electrolytes. According to the preparation method disclosed by the invention, the boric acid ester additive is added into the basic electrolyte, and the boric acid ester is preferentially decomposed in the battery circulation process, so that the generated boron-containing substance can inhibit the side reaction of the electrolyte and increase the stability of the electrolyte; the boric acid ester preferably participates in the formation of electrode / electrolyte interface layers on the two sides of the positive electrode and the negative electrode, and the boric acid ester assists in dissolving NaF with low ionic conductivity at the electrode / electrolyte interface and promotes dissociation of sodium salt in the electrolyte to increase free sodium ions, so that the diffusion rate of the sodium ions is improved, and the performance of the sodium-based half cell and the sodium-based total cell is improved; and the capacity retention ratio and the rate capability of the sodium-nickel iron sodium manganate battery at room temperature or low temperature can be improved.

The invention provides a composite solid electrolyte membrane, a preparation method thereof and a solid-state battery, and relates to the field of energy storage. The preparation method of the composite solid electrolyte membrane comprises the following steps: spraying a sulfide solid electrolyte raw material on the surface of one side of a first substrate layer to prepare an electrolyte membrane precursor; laminating a second base material layer on the surface of one side, where the sulfide solid electrolyte is sprayed, of the first base material layer, and spraying halide solid electrolyte powder on the surface of one side, away from the first base material layer, of the second base material layer to prepare an electrolyte membrane intermediate; and pressing the electrolyte membrane intermediate to prepare the composite solid electrolyte membrane. Wherein the first base material layer and the second base material layer are both of a porous structure. On one hand, the second base material layer can isolate contact between air and the sulfide solid electrolyte to prevent decomposition of the sulfide solid electrolyte, and on the other hand, the sulfide solid electrolyte enters the second base material layer to improve the interface contact problem with the halide solid electrolyte layer.

According to the epoxypropane production system and method with the high conversion rate and the high yield, the interior of the reactor is divided into the upper section and the lower section through the production system, the accurate feeding proportion of three materials is provided, and the mode of segmented control and distributed feeding is provided; propylene and most of hydrogen peroxide diluted by a solvent are added into a first reaction section at the bottom through a first-stage feeding distributor for reaction, and then a reaction mixed solution of the residual solvent and hydrogen peroxide is supplemented into a second reaction section through a second-stage feeding distributor, so that reaction materials are uniformly mixed for reaction; the problem that the temperature is too high and hydrogen peroxide is decomposed due to uneven mixing caused by one-time adding or non-distributed adding of materials is avoided, the conversion rate of the materials is increased, meanwhile, fins are arranged on the outer sides of the catalytic tubes, the heat exchange area is increased, reaction heat is discharged in time, hydrogen peroxide decomposition is avoided, and the catalytic effect is improved. The selectivity and the yield of the product epoxypropane are further improved.

The present invention relates to a photovoltaic water-based soldering flux and a preparation method and application thereof, comprising the following raw materials in parts by weight: 1-5 parts of cosolvent, 0.1-3 parts of wetting agent, 0.1-3 parts of polyethylene glycol, 1-8 parts of activator microcapsules, 0.1-1 parts of antioxidant, and 100 parts of water; wherein the activator microcapsules include capsule cores and capsule materials wrapping the capsule cores, and the capsule cores are composite activators; wherein the composite activator is a composition of an organic acid and a protective agent; the organic acid is a composition of 3-hydroxy-2-naphthoic acid, oleic acid and methylsuccinic acid; the protective agent is a composition of trimethylsiloxane and a quaternary ammonium salt cationic fluorocarbon surfactant. The soldering flux of the present invention uses water as the main solvent, and the soldering flux is more suitable for the preparation of photovoltaic cell chip assemblies with a hot welding temperature of 150-230°C, and the soldering flux can continuously provide activity during welding.

The invention belongs to the technical field of lithium ion batteries, and particularly relates to a lithium ion battery high-voltage electrolyte and a lithium ion battery. The high-voltage electrolyte comprises a lithium salt, a first additive, a second additive, an auxiliary additive and an organic solvent, the first additive is a sulfur-containing siloxy boric acid ester derivative, and the second additive is a benzofuran boric acid ester derivative. Borate groups and benzofuran groups in the first additive and the second additive can promote generation of CEI and SEI protective films on the surfaces of a positive electrode and a negative electrode, the stability of the material is enhanced, electrolyte decomposition is inhibited, and the high-voltage performance of the lithium battery is improved; the trimethylsiloxy group can remove HF in the system, can reduce the corrosion to the positive and negative electrode interface of the battery, and improves the cycle performance of the battery; boron and sulfur atoms in the additive can significantly reduce the internal resistance of the battery and improve the performance of the high-voltage battery at low temperature.

The invention relates to fireproof and heat-insulating glass and a preparation process thereof, and relates to the field of fireproof and heat-insulating materials, the fireproof and heat-insulating glass comprises a heat-insulating film layer I, a fireproof gel layer I, a glass substrate, a fireproof gel layer II and a heat-insulating film layer II, the fireproof gel layer I and the fireproof gel layer II are prepared by adopting a mixed gel solution, the mixed gel solution is prepared from the following raw materials in parts by mass: 80 to 100 parts of bi-crosslinking gel monomer, 5 to 10 parts of crosslinking agent, 20 to 30 parts of composite flame retardant and 1 to 3 parts of initiator. The preparation process comprises the following steps: preparing a mixed gel solution, preparing the fireproof gel layer I and the fireproof gel layer II on the surface of the glass substrate, hot-pressing and laminating the heat insulation film layer I to the surface of the fireproof gel layer I, and hot-pressing and laminating the heat insulation film layer II to the surface of the fireproof gel layer II to obtain the fireproof heat insulation glass. The fireproof and heat-insulating glass has the effect of improving the interlayer binding force of the fireproof and heat-insulating glass, the stability can be improved, and the fireproof and heat-insulating performance is further improved.

The utility model discloses super-strong steel chemical degreasing powder drying equipment, and relates to the technical field of drying equipment. The device comprises a drying assembly, and an inner cavity of the drying assembly is fixedly connected with a mixing assembly. The heating blocks embedded in the inner wall of the drying box are distributed in an annular array mode, oil removing powder in the drying box can be heated in a full-surrounding mode, compared with traditional bottom or single-side heating, the uniformity of a temperature field in the box is remarkably improved, and the problem of component decomposition or low-temperature caking caused by local overheating is solved; when the planetary gear stirring piece drives the auxiliary stirring rod to revolve around the first transmission shaft, rotation is achieved through meshing of the driven gear and the driving gear ring, and a three-dimensional stirring track of revolution and rotation is formed; the up-down reciprocating piece pushes the main stirring rod to do periodic up-down motion through the cam, so that materials are subjected to transverse shearing mixing and longitudinal stirring in the drying process, the material accumulation dead angle is effectively broken, and the heat exchange efficiency is improved.

The invention discloses an electrolyte for a soft package cylindrical battery. The electrolyte comprises the following components in parts by weight: 10-25 parts of lithium salt, 60-85 parts of an organic solvent and 5-15 parts of a functional additive, the lithium salt is prepared from 10 to 18 parts of lithium hexafluorophosphate, 2 to 5 parts of lithium bis (fluorosulfonyl) imide and 0.1 to 1 part of lithium difluorophosphate; the organic solvent is prepared from 10 to 20 parts of ethylene carbonate, 30 to 45 parts of propyl propionate, 10 to 20 parts of ethylene carbonate and 5 to 10 parts of propylene carbonate; the functional additive is prepared from 0.5 to 2 parts of vinylene carbonate, 1 to 3 parts of propylene sulfite, 3 to 8 parts of ethylene sulfate, 0.5 to 1.5 parts of fluoroethylene carbonate, 0.1 to 0.5 part of lithium bis (oxalato) borate and 0.1 to 0.5 part of lithium bis (oxalato) borate. The electrolyte disclosed by the invention is applied to the soft package cylindrical battery, the permeability and infiltration efficiency of the electrolyte can be remarkably improved, and the electrochemical performance of the battery is improved.

According to the drying method of the polyester plain weave fabric base coating cloth with the Chinese art paper wetting effect, citric acid serves as an intermediate medium and adheres to the surface of polyester, and esterification reaction between the citric acid and coating cloth slurry is promoted; the problem of citric acid decomposition caused by overheating in the drying process is solved, so that the combination of the polyester and the mixed slurry is firmer; meanwhile, through one-way control over hot air, the sizing agent can permeate into polyester pores under the action of wind power in the drying process, and therefore three-dimensional combination is formed between the polyester and the sizing agent; and meanwhile, citric acid is fully reserved, so that the formed coated fabric has hygroscopicity.

The invention discloses a method for synthesizing branched polyester by using polyester and a carbon dioxide derivative and a product thereof. The method comprises the following steps: carrying out solid-phase ester exchange reaction on a carbon dioxide derivative and polyester under inert gas protection and heating conditions to obtain branched polyester; the carbon dioxide derivative is prepared from at least one of 3-ethylidene-6-vinyl tetrahydro-2H-pyran-2-ketone and a homopolymer pEVL (Poly (Ethylene Vinyl Vinyl) L) thereof. According to the invention, a large amount of polyester materials and carbon dioxide wastes can be utilized, so that the current relatively difficult problems of carbon emission and pollution are solved.

The invention provides a green-protecting preservative as well as a preparation method and application thereof, and relates to the technical field of fruit preservation. The green-protecting preservative disclosed by the invention is prepared from the following components in parts by weight: 20 to 40 parts of chitosan, 1 to 5 parts of 6-benayl aminopurine, 1 to 5 parts of gibberellic acid, 10 to 20 parts of citric acid and 3 to 10 parts of cortex cinnamomi extract. The green-protecting preservative disclosed by the invention is safe and simple to use, and can well maintain the color of the green lemons, delay the degradation of chlorophyll in the peel of the green lemons, maintain the fragrance of the green lemons and reduce the morbidity of diseases and insect pests such as black spots of the green lemons during storage, the color of the green lemon fruits changes slowly during storage, and the quality of the fruits is well maintained.

The invention relates to the field of new energy materials, and discloses a high-rate low-temperature-resistant electrolyte adaptive to a high-density polyphenylene sulfide solid diaphragm, a preparation method and a lithium battery, and an organic solvent of the electrolyte comprises acyclic carbonate, cyclic carbonate, a cosolvent and a film-forming additive. The cosolvent is linear ester of which the freezing point is lower than-40 DEG C; the acyclic carbonate which can generate weak dipole adsorption or repulsive interaction with the surface of high-crystallization polyphenylene sulfide is selected as the acyclic carbonate, and the solvent can form a solvation cluster with Li < + > in the electrolyte and can accelerate Li < + > desolvation on the surface of the PPS solid diaphragm, so that Li < + > smoothly passes through a sulfur channel, and the rate capability of the battery is improved; the linear ester with low freezing point makes up the defect that the freezing point of cyclic carbonate and acyclic carbonate is too high, so that the battery can normally work at-20 DEG C, and the low-temperature performance of the electrolyte is improved. By adding the film-forming additive, the safety of the battery is improved, and the cycle life of the battery is prolonged.

The invention relates to the technical field of fertilizers, and discloses a water-retaining slow-release fertilizer and a preparation method thereof. The nitrogen fertilizer is prepared from the following raw materials in parts by weight: 30 to 40 parts of nitrogen fertilizer, 15 to 20 parts of chitosan, 1 to 2 parts of urease inhibitor, 3 to 5 parts of maleic anhydride grafted compatilizer, 100 parts of acetic acid solution, 20 to 25 parts of acrylamide, 1 to 2 parts of 2-mercaptobenzoic acid, 0.4 to 0.6 part of ammonium persulfate, 0.4 to 0.6 part of tetramethylethylenediamine, 4 to 6 parts of calcium carbonate powder, 10 to 15 parts of talcum powder and 0.3 to 0.5 part of nitrification inhibitor. According to the invention, chitosan and acrylamide are copolymerized and prepared into the hydrogel, and the three-dimensional network structure contains a large amount of hydroxyl groups, so that the water absorption and holding capacity of the polymer can be greatly improved. The nitrogen fertilizer is wrapped by a three-dimensional network structure of the polymer, is gradually hydrolyzed when encountering water, and cooperates with the urease inhibitor grafted on the polymer and a coating film formed on the surface, so that an efficient slow-release and controlled-release effect is achieved.