80results about How to "Low mechanical strength" patented technology

The invention relates to a stem cell bioactive nano-vesicle with efficient inflammation regulation and tissue repair effects, the average particle size of the nano-vesicle is 100-350nm, the polydispersity index (PDI) is 0.05-0.40, and the expression rate of phosphatidylserine (PS) on the surface of the nano-vesicle is greater than 40%. According to the preparation method, stem cells are subjected to apoptosis induction, and then a programmed serial extrusion process is adopted to prepare the nano-vesicles. The nano vesicles are moderate in particle size, uniform in distribution and high in production efficiency, the preparation process is easy to operate, the quality is stable and controllable, and the nano vesicles have excellent technical effects in the aspects of repair and regeneration of inflammation injury type tissues and organs.

The invention discloses 3D printing low-carbon concrete containing modified recycled aggregate and a micro-powder reinforcer. The 3D printing low-carbon concrete is prepared by the following steps: (1) putting recycled concrete coarse aggregate into sodium or potash water glass, and performing ultrasonic treatment; then separating the coarse aggregate, performing carbonization treatment, and heating the obtained coarse aggregate to obtain the pretreated recycled aggregate. And (2) placing the pretreated recycled aggregate in saturated lime water, and carrying out heating and heat preservation treatment to obtain the modified recycled aggregate. And (3) forming a wet material from the waste cement slurry powder, gamma-C2S powder and water, performing carbonization treatment on the wet material, performing heating treatment, and grinding the obtained solid to obtain the modified regenerated micro-powder enhancer. And (4) uniformly mixing the cement, the modified recycled aggregate, the fine aggregate, the micro-powder enhancer, the water reducing agent and the water to obtain the concrete. The process provided by the invention not only improves the mechanical strength and fluidity of the 3D printing concrete prepared from the recycled concrete aggregate, but also consumes carbon dioxide and reduces carbon emission.

The invention relates to the technical field of diode detection, in particular to a vehicle gauge level diode detection method, which comprises the following steps of: acquiring a plurality of pieces of image information of each view of a diode to construct a spatial model of the diode, and determining the qualification of the spatial form of diode packaging based on the overall fitting degree of the spatial model. And determining the diode packaging qualification based on the straight line contact ratio of the pins. Carrying out preliminary detection by using a universal meter based on the packaged qualified diode, and determining the minimum dynamic resistance based on the volt-ampere characteristic curve of the diode under the condition that the access is qualified so as to carry out preliminary grading on the performance of the diode; and the detection voltage is matched based on the preliminary grading result, the temperature of the diode is monitored in real time in the detection process to establish a temperature fluctuation curve, and the maximum change rate and the change range of the temperature are determined based on the temperature fluctuation curve to determine whether the fluctuation evaluation value is adjusted to re-determine the performance grading of the diode. According to the invention, the performance detection efficiency of the diode is improved.

The invention relates to a bismuth scandate-lead titanate based piezoelectric ceramic material and a preparation method and application thereof, the chemical general formula of the bismuth scandate-lead titanate based piezoelectric ceramic material is (1-y) Bi (Sc (1-x) Mex) O3-yPbTiO3, Me is a late transition metal element, x is 0.03-0.3, and y is 0.63-0.64. Compared with the prior art, the piezoelectric anisotropy and the piezoelectric property of the piezoelectric ceramic are improved by doping the rear transition group metal element Me on the basis of the BiScO3-PbTiO3 binary system piezoelectric ceramic material, the piezoelectric constant d33 is greater than 500pC / N, and the piezoelectric anisotropy d33 / d31 is greater than 3.5.

The invention discloses a high-reliability long-acting anti-termite cable, and belongs to the technical field of cables, the high-reliability long-acting anti-termite cable sequentially comprises a conductor, an insulating layer, a conductor shielding layer, an aluminum sheath layer and a PE outer sheath from inside to outside, and the PE outer sheath comprises the following components in parts by weight: 100 parts of polyethylene and 20-50 parts of thermoplastic elastomer. The preparation method comprises the following steps: adding the surface-modified silicon dioxide microcapsule into a PE outer sheath material, using silicon dioxide as a capsule wall material of the self-repairing microcapsule, and using a repairing agent and an anti-termite agent as capsule core materials; and the surface of the silicon dioxide is modified with a methoxypolyethylene glycol chain segment with a dispersion effect and a vanillyl nonanoate amide chain segment with an anti-ant effect, so that the high-reliability long-acting anti-ant effect is achieved.

The invention relates to a hydrated borate micromolecule with a boron-nitrogen coordination bond, a derivative resin material and a preparation method of the hydrated borate micromolecule. The preparation method comprises the following steps: S1, synthesizing boron-nitrogen coordination micromolecules: dissolving and reacting boric acid, a derivative thereof and a polyfunctional group amine compound at room temperature through a solution reaction to obtain the boron-nitrogen coordination micromolecules; the borate micromolecule NCBW-X with intramolecular boron and nitrogen coordination is formed; s2, the NCBW-X micromolecule can be used for curing epoxy resin and synthesizing materials such as phenolic resin through end-NH2 and end-OH on two sides, the NCBW-X improves the mechanical property of each system through a rigid eight-membered ring, boron-nitrogen coordination of the NCBW-X can generate hydration, the environmental endurance is improved on the premise of retaining the original dynamic nature of boric acid ester of the NCBW-X, and the service life of the NCBW-X micromolecule is prolonged. Meanwhile, due to the dynamic reversibility of the NCBW-X, the NCBW-X is used for curing epoxy resin, and materials such as phenolic resin and the like are improved to a certain extent in the aspects of self-repairing and recycling.

The invention discloses a flame-retardant antistatic rubber material for a conveying belt and a preparation method of the flame-retardant antistatic rubber material, and relates to the technical field of rubber materials. The rubber material is prepared from the following components: 40-80 parts of chloroprene rubber, 10-40 parts of butadiene rubber, 10-30 parts of high styrene rubber, 20-40 parts of a reinforcing agent, 15-30 parts of an antistatic agent, 10-30 parts of aluminum hydroxide, 10-20 parts of a modified flame retardant, 5-10 parts of polyethylene fibers, 5-10 parts of zinc stearate, 3-6 parts of a coupling agent, 4-8 parts of a vulcanizing agent, 1-3 parts of an accelerant and 1-3 parts of an anti-aging agent. Basic performance is provided through a compounding system of three kinds of rubber, the mechanical performance is improved by adopting an attapulgite-carbon black compounding reinforcing system, and the antistatic and flame-retardant functions are achieved in combination with the antistatic agent and the specially-made modified flame retardant.

A method for preparing conductive concrete comprises the following steps: firstly, evenly mixing expandable graphite, concrete raw materials and carbon fibers to obtain an initial mixture, then adding water to the initial mixture and stirring to obtain concrete slurry, then curing the concrete slurry to obtain a solidified body, and then heating the solidified body to expand the expandable graphite, thereby obtaining the conductive concrete, and the heating temperature is 200°C-600°C. This design not only has better conductivity and lower production cost, but also can improve mechanical properties, and has a wide range of applications, such as indoor climate control, road deicing or cooking.

The invention belongs to the technical field of lining pipe production equipment, and mainly provides a heat distribution pipeline lining pipe with a heat insulation effect and lining pipe production equipment. Comprising an extrusion device, the extrusion device is provided with a sleeve, the sleeve is fixedly connected with first hard pipes which are evenly distributed in the circumferential direction, the first hard pipes are communicated with spraying heads, the first hard pipes which are evenly distributed in the circumferential direction are jointly communicated with a first annular shell, the first annular shell is communicated with a second hard pipe, and the second hard pipe is communicated with a connecting shell. The sleeve communicates with third hard pipes which are evenly distributed in the circumferential direction, the third hard pipes which are evenly distributed in the circumferential direction jointly communicate with a second annular shell, and the sleeve is fixedly connected with a fan. Water is sprayed to the surface of the lining pipe through the spraying heads evenly distributed in the circumferential direction, the water attached to the surface of the lining pipe cannot flow downwards through the draught fan, and therefore the situation that the lining pipe is cooled unevenly due to the fact that water flow moves downwards is avoided, and the mechanical strength of the lining pipe is prevented from being reduced in the production process.

The invention provides a light heat-proof and heat-insulation phenolic resin-based composite material and a preparation method thereof. The light heat-proof and heat-insulation phenolic resin-based composite material comprises a reinforcing material and a resin matrix, the resin matrix comprises phenolic resin, a modifier and a light filler; the mass of the modifier is 0.5%-5% of the mass of the phenolic resin; the mass of the light filler is 30-70% of the mass of the phenolic resin; and the modifier is dicyandiamide. The density of the composite material is 0.6-0.9 g / cm < 3 >, and the composite material meets use requirements, is excellent in mechanical property, is formed by adopting a non-autoclave, and is low in manufacturing cost and high in production efficiency.

The present invention discloses a low-viscosity and high-strength cement-based grouting material and a preparation method thereof. The grouting material comprises the following components: 300-600 parts of a cementitious material having volcanic ash properties, 0.2-0.6 parts of a micro-nano coagulant, a water reducer of 0.25-2% of the mass of the cementitious material, and a water-cement ratio of 0.4-0.8. The cementitious material having volcanic ash properties comprises silicate cement and modified microbeads. The preparation method comprises the following steps: uniformly mixing the cementitious material having volcanic ash properties and the micro-nano coagulant. Then, a mixed solution formed by the water reducer and water is added, and the mixture is uniformly stirred to obtain the cement-based grouting material. The present invention reduces the water-cement ratio of cement slurry and ensures the strength of cement stone, while reducing the viscosity of cement slurry and improving injectability.

The invention relates to a PVDF (Polyvinylidene Fluoride) polymer lateral chromatography membrane and a preparation method thereof, and according to the method, a large-aperture PVDF membrane is prepared by blending a hydrophilic additive with high molecular weight and PVDF powder. The method comprises the following steps: mixing PVDF powder with a hydrophilic pore-foaming agent (such as PVP, PEG and the like) by adopting a solution blending method, performing non-solvent induced phase separation (NIPS) to form a membrane, immersing the membrane into a coagulating bath for a period of time, transferring the membrane into deionized water for soaking, taking out the membrane after the solvent is completely removed, and drying the membrane at normal temperature to form the membrane. And immersing the membrane in a surfactant solution for a period of time, taking out the membrane, and naturally airing the membrane so as to obtain the PVDF flat membrane which has a macroporous structure, a good pore structure, hydrophilicity and protein adsorption performance.

The invention belongs to the technical field of biomedical materials, and particularly relates to an agarose gel implant with good injection performance. The preparation method comprises the following steps: dissolving agarose in a buffer solution at 90-120 DEG C to obtain a clear and transparent solution, cooling to 40-55 DEG C, adding alkali and a chemical cross-linking agent, stirring to react for 2-5 minutes, standing to react for 4-24 hours at 5-35 DEG C, and dialyzing and homogenizing to obtain the chemical cross-linked agarose hydrogel implant. Compared with agarose hydrogel formed by self-aggregation physical action, the agarose gel implant has better injection performance, and the injection chirality of an injection person and the comfort of an injected person are improved.

A method for preparing conductive concrete with high mechanical properties, firstly bonding multiple expandable graphite particles on the outer periphery of conductive fibers, then standing to wait for bonding and curing to obtain graphite fibers, then uniformly mixing multiple graphite fibers with concrete raw materials, then adding water and stirring to obtain concrete slurry, then standing the concrete slurry to cure to obtain a solidified body, then connecting the two ends of the solidified body to a circuit to energize the solidified body, the graphite fibers after energization heat up, the heating temperature is 200℃-500℃, when the expandable graphite particles in the solidified body expand due to heat, the conductive concrete with high mechanical properties can be obtained. This design not only has better interface performance and can improve the mechanical strength of the final product, but also has better conductive effect and lower production cost.

The invention discloses a molecular sieve-based flame-retardant material and a preparation method thereof, the molecular sieve-based flame-retardant material comprises a hollow molecular sieve and a flame retardant, the hollow molecular sieve is a hollow structure with micropores, and the flame retardant is coated or embedded in the micropores and the hollow structure of the hollow molecular sieve and / or the crystal surface of the hollow molecular sieve; the preparation method comprises the following steps: C1, introducing a flame retardant into the hollow molecular sieve through a dipping or dissolving method, so that the flame retardant is partially adsorbed in micropores and / or on the surface of the hollow molecular sieve; c2, mixing a hollow molecular sieve containing a flame retardant with the crystallization solution, and carrying out a hydrothermal heavy crystallization reaction at 120-180 DEG C; c3, after the re-crystallization reaction is finished, separating the sample in a filtering or centrifuging manner, cleaning the sample with deionized water, and removing an unreacted crystallization solution; and C4, drying the sample separated in the step C3 to obtain the molecular sieve-based flame-retardant material. The heat stability and the flame-retardant effect are improved.

The present invention provides a kind of lignite for honeycomb activated carbon and its quality improvement and modification method, honeycomb activated carbon, the quality improvement and modification method of lignite for honeycomb activated carbon, comprising the following steps: taking lignite powder, adding an aqueous solution of sodium borohydride, mixing evenly, performing a reduction reaction, and obtaining reduced lignite; mixing the reduced lignite with a thermal stability regulator, 9,10-dihydrophenanthrene, and N,N-dimethylformamide evenly, performing a swelling treatment, and obtaining swollen lignite; mixing the swollen lignite with aniline evenly, stirring the reaction, and obtaining lignite for honeycomb activated carbon. The lignite obtained by the quality improvement and modification method of the present invention for honeycomb activated carbon is not easy to return to white, is not easy to crack after being made into honeycomb activated carbon, has good mechanical strength, and has good thermal stability.

This application relates to a femtosecond laser multi-degree-of-freedom personalized reshaping method and system for intracorneal implants, belonging to the field of femtosecond laser processing technology. Utilizing the cold processing characteristics of femtosecond lasers, the intracorneal implant is individually cut and ablated to obtain the desired three-dimensional corneal shape, precisely shaping the curvature, thickness, and contour of the lens to perfectly match the patient's corneal capsule or lesion area. By leveraging the nonlinear optical effect induced at the focal point of the femtosecond laser, the stromal collagen network in the weak areas corresponding to corneal expansion can be densified through laser processing, significantly improving the local elastic modulus and resistance to deformation. In areas requiring a smooth transition with the recipient cornea or adjustment of refractive power, controllable micropores or low-density areas can be induced, appropriately reducing local stiffness, thereby achieving a spatial gradient distribution of internal mechanical properties and customizing the overall mechanical behavior and morphological stability after implantation.

A problem to be addressed by the present invention is to enable a plating layer having excellent surface smoothness to be formed without compromising the various excellent properties inherent in polyphenylene sulfide resins, and to provide a plated molding which is excellent in adhesiveness of the plating layer and ensures high plating quality even in severe environmental degradation tests such as thermal shock cycle tests as well as a method of producing thereof. To solve the above problem, a main object of the present invention is to provide plated molding having a plating layer formed on a part or all of the surface of the molding that is molded with a polyphenylene sulfide resin composition including 30 to 200 parts by weight of a fibrous filler (B) based on 100 parts by weight of a polyphenylene sulfide resin (A), wherein an arithmetic mean roughness of the surface of the plating layer of the plated molding is 1.5 µm or less.

This invention relates to the field of polymer foaming materials technology, and discloses a plant fiber composite nucleating agent for microfoaming of biodegradable materials and its application. The plant fiber composite nucleating agent is made from raw materials comprising the following parts by weight: 80-95 parts of primary ultrafine plant fiber powder, 5-20 parts of surface modifier, and 0.1-5 parts of dispersing lubricating wax; the surface modifier and dispersing lubricating wax are coated on the surface of the primary ultrafine plant fiber powder. The application steps are as follows: adding the plant fiber composite nucleating agent to a biodegradable material matrix to obtain a pre-foaming blend, introducing foaming gas or adding a chemical foaming agent for foaming treatment. The nucleating agent of this invention improves the compatibility between plant fibers and hydrophobic biodegradable matrices, provides heterogeneous nucleation sites in the matrix while increasing the polymer melt strength, inhibits cell coalescence and rupture, and obtains microfoamed materials with uniform pore size. Furthermore, the nucleating agent itself is completely biodegradable.

The present invention relates to a biodegradable polyester polymer with excellent transparency and impact strength and a biodegradable polymer composition comprising same. Particularly, the biodegradable polyester polymer is prepared from: a dicarboxylic compound including aromatic dicarboxylic acid or aromatic dialkylcarboxylate, and aliphatic dicarboxylic acid; an aliphatic glycol compound; and a polymerizable composition including a polypropylene sebacate oligomer, and thus can realize improved transparency and impact strength.

Provided are an acoustic matching layer material containing an epoxy resin (A) component having an epoxy equivalent weight of 140 or less and metal particles (B) having a density of 10 g / cm3 or more at 20°C, in which a content of particles (C) having a density of less than 4.5 g / cm3 at 20°C is less than 5% by mass; an acoustic matching sheet; a composition for an acoustic matching layer material; an acoustic wave probe; an acoustic wave measurement apparatus; and a manufacturing method of an acoustic wave probe.

The invention belongs to the technical field of umbrella-shaped vacuum ceramic tube shells, and particularly relates to a preparation process of an umbrella-shaped vacuum ceramic tube shell, which comprises the following steps: firstly, designing a die sleeve; the die sleeve is made of an organic elastic material, and corrugations are prefabricated on the inner circular surface of the die sleeve; the steel mold core is arranged in the mold sleeve, and a cavity area formed by the steel mold core and the mold sleeve is filled with aluminum oxide powder; covering a steel plug on the upper side of the alumina powder to form a to-be-pressed whole; the whole to be pressed is subjected to isostatic pressing forming, the die sleeve and the aluminum oxide powder are compressed and formed towards the center of the steel die core at the same time through the corrugated shape of an inner cavity of the die sleeve under the applied pressure, and a blank piece is formed; after isostatic pressing is finished, pressure relief is started, and the steel mold core, the blank piece and the mold sleeve rebound; and removing the steel plug, and taking out the formed aluminum oxide blank to obtain the umbrella-shaped vacuum ceramic tube shell. The problem that in existing machining, turning is needed, and the quality of finished products cannot be guaranteed is solved.

The invention relates to the field of gypsum-based building materials, and particularly discloses a preparation method of a lysine-tannic acid compound retarder and a gypsum-based building material.The preparation method comprises the following steps that 1, tannic acid and copper acetate are added into water to be stirred, and a copper-tannic acid pre-coordination solution is obtained; then adding L-lysine into the mixture, and stirring for reaction to obtain precursor liquid after the reaction is completed; and (2) adding glyoxal into the precursor liquid for reaction, and then adding dialdehyde polyethylene glycol for continuous reaction to obtain the compound retarder. The gypsum-based building material comprises the following components: alpha-semi-hydrated gypsum, cement, slag powder, the lysine-tannic acid compound retarder, a water reducing agent and mixing water. The retarder provided by the invention not only has a good retarding effect on the gypsum-based building material, but also can improve the early strength of the gypsum-based building material, and effectively overcomes the contradictory problem of retarding and early strength.

The powder material for additive manufacturing disclosed herein includes tungsten carbide (WC), cobalt (Co), and a carbon additive including carbon (C) as a main constituent element, and the value of a carbon content A (% by mass), which is represented by the following formula: [(mass of C derived from WC) + (mass of C derived from carbon additive)] / (mass of WC) × 100, satisfies the condition of 6.4 ≤ A ≤ 7.2.

The invention relates to the technical field of nylon, and discloses a preparation method of montmorillonite grafted ethylene propylene rubber modified nylon 6 fiber, amino modified nano montmorillonite and isocyanate modified ethylene propylene rubber are subjected to a reaction, polyethylene glycol modified nylon 6 and montmorillonite grafted ethylene propylene rubber are mixed through an electrostatic spinning method, and the montmorillonite grafted ethylene propylene rubber modified nylon 6 fiber is obtained. Nano-montmorillonite is connected to ethylene-propylene rubber through chemical bonds, so that agglomeration of the nano-montmorillonite is avoided, stress concentration effect generated when the nano-montmorillonite is impacted by external force is avoided, a nylon 6 matrix is stimulated to generate microcracks, and a large amount of impact energy is consumed. The ethylene-propylene rubber has a sea-island microstructure, so that crazing can be inhibited when the ethylene-propylene rubber is impacted by external force, matrix breakage is avoided, and the mechanical property of the mixed composite fiber material is greatly improved.

The invention discloses a lightning protection insulator, and relates to the technical field of insulators, the lightning protection insulator comprises an insulator main body, the upper end of the insulator main body is provided with a mounting base, the lower end of the insulator main body is provided with a steel foot bolt, the circumferential surface of the mounting base is rotatably provided with a rotating ring through a bearing, and the upper end of the mounting base is provided with an insulating shield. A high-voltage wire is arranged between the mounting base and the insulating protective cover in a penetrating mode, two multi-connecting rods in the dust removal device can drive multiple sets of dust removal mechanisms to rotate, and first scraping rods in the dust removal mechanisms are attached to the upper ends of composite umbrella groups; at the moment, the first scraping rod can clean dust, salt mist, industrial pollutants and the like at the upper end of the composite umbrella group, and the situation that the dust, the salt mist, the industrial pollutants and the like stay on the composite umbrella group for a long time, the insulation performance of the composite umbrella group is reduced, partial discharge is caused, creepage traces are formed, and finally flashover or short-circuit accidents possibly occur is avoided; and the safety of the equipment is effectively improved.

The invention belongs to the technical field of concrete, and discloses application of thermosetting plastic in preparation of hydrophobic concrete and a product. The hydrophobic concrete product is prepared from the following ingredients in parts by mass: 10 to 60 parts of thermosetting plastic powder, 20 to 30 parts of cement, 5 to 50 parts of quartz sand, 5 to 10 parts of fly ash and 25 to 35 parts of polyacrylamide-containing aqueous solution. The concentration of the polyacrylamide is 0 to 8000 ppm. According to the concrete product provided by the invention, the hydrophobic property of the concrete product is improved, the water absorption rate is reduced, the mechanical strength of cement is not greatly reduced, solid waste resources are effectively utilized, and the concrete product has a wide application prospect.

This utility model provides a pressure relief and explosion-proof structure for an electromagnetic unit and a capacitive voltage transformer, belonging to the field of capacitive voltage transformers. It includes an electromagnetic unit with a pressure relief and explosion-proof structure. The structure includes a pressure relief hole on the outer casing of the electromagnetic unit, and a pressure relief plate detachably mounted on the outside of the pressure relief hole. The pressure relief plate is made of transparent material, and an oil level line is provided on its surface. The beneficial effect of this utility model is that it integrates explosion-proof pressure relief and oil level observation functions into one unit, enabling both pressure safety release and oil level monitoring, thereby reducing equipment complexity and maintenance costs, and providing a better solution for the safe and stable operation of capacitive voltage transformers.

The utility model discloses a kind of corrosion-resistant LED lamps, including lamp shell, the lamp shell is equipped with inner chamber, the inner chamber is equipped with LED lamp pearl, the surface of lamp shell is equipped with protective layer, the protective layer includes the several protective pieces one of longitudinally arranged and the several protective pieces two of transversely arranged, the rear end of protective piece two and the front side of corresponding protective piece one are abutted;It also includes the metal edging strip of detachable connection with protective layer, metal edging strip is set to flexible metal material of bendable, the metal edging strip is connected and fixed with protective piece two and protective piece one of adjacent protective piece two;Protective layer is designed as detachable module, when local damage, can be replaced alone, reduce maintenance cost;When protective layer is damaged, humidity sensor detects humidity signal and passes to controller, controller identifies when higher than preset value, control buzzer to sound, to remind user.

The invention discloses a sand mold material for casting chrome corundum and a preparation method and application thereof, the sand mold material comprises a flexible layer and a contact layer, and the flexible layer is mainly prepared from casting chromium oxide aggregate, alpha-alumina powder, a bonding promoting agent, a bonding agent, mullite fibers and polyoxyethylene alkylphenol ether as raw materials; the contact layer takes rho-aluminum oxide powder, alpha-aluminum oxide powder, chromium micro powder, zirconium oxide micro powder, aluminum sol and magnesium oxide micro powder as raw materials, the flexible layer is formed in a mechanical pressing mode and then dried, a contact layer mixture is smeared on the upper surface of the contact layer according to a certain thickness, then drying is conducted, and the sand mold is assembled after drying. The invention aims to provide a sand mold template material which still has certain high-temperature mechanical strength in the long-time scouring process of high-temperature melt and meets the requirement of high-temperature casting of fused and cast chromium corundum refractory materials.