42results about How to "Improve volume change" patented technology

A set volume control device for an on-vehicle audio system includes: a volume control switch to which a vehicle occupant can arbitrarily give an operational input; and a controller for controlling a set volume changer based on a vehicle speed detected by a vehicle speed detector and the operational input to the volume control switch so that a set volume of an audio system becomes a low vehicle speed region set volume fixed independently of vehicle speed change in a low vehicle speed region; becomes a high vehicle speed region set volume fixed independently of the vehicle speed change in a high vehicle speed region; and changes according to the vehicle speed change along a predetermined medium vehicle speed region set volume change line connecting the low vehicle speed region set volume and the high vehicle speed region set volume in a medium vehicle speed region between the low vehicle speed region and the high vehicle speed region. The controller changes a setting of the low vehicle speed region set volume according to an operational input to the volume control switch within a first volume setting range set up in advance when the volume control switch is operated in the low vehicle speed region, and changes a setting of the high vehicle speed region set volume according to an operational input to the volume control switch within a millisecond volume setting range set up in advance when the volume control switch is operated in the high vehicle speed region. A lower limit of the millisecond volume setting range is set higher than an upper limit of the first volume setting range. Thus, it is possible to accurately control the volume of the audio system and improve feeling of volume change.

The invention relates to the technical field of sodium ion battery materials, and in particular to a preparation method of a sodium vanadium phosphate sodium ion battery composite material. The preparation method provided by the invention comprises the following steps of 1: mixing, ball milling and drying a sodium source, a vanadium source and a phosphorus source to obtain sodium vanadium phosphate precursor powders; 2: pre-sintering and sintering the sodium vanadium phosphate precursor powders is a non-oxidizing atmosphere to obtain sodium ion battery cathode material sodium vanadium phosphate; 3: dissolving a organic carbon source in a dispersant, adding the sodium vanadium phosphate and stirring the mixture in a water bath, evaporating the mixture until a gel is formed, and drying and milling the gel to obtain mixed powders; and 4, mixing and grinding a compound containing the Y element and the mixed powders obtained in the step 3, sintering the mixture at 300 to 500 degrees centigrade for 0.5 to 3 hours to obtain the sodium vanadium phosphate sodium ion battery composite material. The method can solve the technical problem that the existing sodium vanadium phosphate has low electronic conductivity and thus seriously limits its rate performance and cycle performance.

The invention relates to a silicon-carbon composite assembled battery. The silicon-carbon composite assembled battery is prepared by steps: (1) adding silicon powder into NaOH solution containing various mixtures and being smaller than 30% in mass ratio, vibrating ultrasonically, filtering and drying to remove surface impurities and oxides of silicon, wherein the mixtures include carbohydrates, high polymers, silicon powder and organic solvents in a mass ratio of 1:1:0.5:5-1:0.1:0.1:0.5; (2) dissolving citric acid in absolute ethyl alcohol to obtain citric acid/ethanol solution with concentration being 0.4g/ml; adding the silicon powder processed at the step 1 into the citric acid/ethanol solution according to an addition quantity of 2g/ml, ultrasonically stirring for reaction for 30min, and subjecting the mixed solution to spray pyrolysis in air at 400 DEG C to obtain the silicon-carbon composite assembled battery. Easiness in raw material acquisition, low cost and simplicity in preparation are realized, and the prepared silicon-carbon composite is small and controllable in size.

The invention discloses a tremella-shaped nanosphere material assembled by inlaying molybdenum dioxide nanoparticles into carbon nanosheets, preparation of the tremella-shaped nanosphere material andapplication of the tremella-shaped nanosphere material in a sodium ion battery. In the material, MoO2 nanoparticles are inlaid in amorphous carbon nanosheets, the carbon nanosheets are interwoven andassembled into tremella-shaped nanospheres, and a large number of mesopores and other pores exist between the carbon nanosheets. The preparation method comprises the following steps of polymerizing ammonium molybdate and dopamine hydrochloride to form a precursor, and calcining to decompose and carbonize, thereby obtaining the final product. The electrochemical activity, the structural stability and the cycling stability of MoO2 can be improved, so that MoO2 has higher specific capacity and more stable cycling performance. The tremella-shaped nanosphere assembled by inlaying MoO2 nanoparticlesinto carbon nanosheets has a remarkable application value when being used as an electrode material of a sodium-ion battery.

The invention discloses a carbon/titanium dioxide coated tin oxide nano particle/carbon assembled mesoporous sphere material as well as preparation and application thereof in a lithium ion battery negative electrode material. In the material, SnO2 nano particles are assembled into mesoporous spheres through carbon, and the surfaces of the SnO2 mesoporous spheres are coated with a layer of TiO2 nano crystals and a layer of amorphous carbon. The preparation method comprises the following steps: firstly, synthesizing SnO2 nano particle/carbon assembled mesoporous spheres by a hydrothermal method,then coating TiO2 by a hydrolysis method, finally coating a layer of resorcinol-formaldehyde resin, and carbonizing to obtain a final product. According to the invention, the electrochemical activity, the structural stability and the cycling stability of SnO2 can be improved, so that SnO2 has high specific capacity and stable cycling performance. The carbon/TiO2 coated SnO2 nano particle/carbon assembled mesoporous sphere has an important application value as a lithium ion battery negative electrode material.

The invention relates to a preparation method for a silicon-carbon composite material, and belongs to the technical field of carbon composite material preparation. The preparation method comprises the specific steps that carbohydrate, high polymer, silicon powder and organic solvent are subjected to reaction in a sealed vessel at the temperature ranging from 150 DEG C-250 DEG C, and the silicon-carbon composite material is obtained through drying and calcination. The preparation method for the silicon-carbon composite material has the advantages that the needed material is easy to acquire, the cost is low, and the preparation process is easy. The prepared silicon-carbon composite material has the advantages of being small and controllable in size, high in the specific capacity and excellent in the cycle performance.

The invention discloses a concrete crack repair material and a preparation method and an application method thereof, and solves the problems of properties to be improved and limited adaptive range of the existing concrete crack repair materials. The preparation method comprises the steps: mixing waste glass, mineral powder, portland cement, a water reducer and molasses according to proportions by weight, then putting the mixture into a wet mill and adding water for milling to prepare slurry; and adding triethanolamine, warm round glue, azobisformamide, a defoamer, a poly-propionate emulsion, dispersible latex powder and fine sand proportionally to the slurry and uniformly mixing the materials. The preparation method has a simple process, convenient control, low production cost and environmental friendliness, and the prepared concrete crack repair material has high strength, high liquidity, low bleeding rate, high cohesiveness and certain swelling property.

The invention provides a Fe2O3/FeF3-2xOx/Fe<3+>,Co<2+> doped bismuth fluoride layer structure positive electrode material of a lithium battery and a preparation method thereof. According to the method, Fe<3+>,Co<2+> doped bismuth fluoride is prepared through solid-phase synthesis; then on the basis of the characteristic that FeF3 is prone to gradual oxidation into Fe2O3 at a high temperature, FeF3-2xOx (wherein 0<x<0.3) and a Fe2O3 layer successively coat Fe<3+>,Co<2+> doped bismuth fluoride particles so as to improve surface electron conduction capability of Fe<3+>,Ce<4+> doped bismuth fluoride and to resist harmful effect of an organic electrolyte on particle surfaces; and comprehensive electrochemical performance of bismuth fluoride is greatly improved through Fe<3+>,Co<2+> doping.

Hydraulic fluid is supplied from a hydraulic fluid supply opening to a hydraulic fluid supply portion. The hydraulic fluid in the hydraulic fluid supply portion is supplied to a primary hydraulic fluid storage chamber and to a secondary hydraulic fluid storage chamber via a hydraulic fluid supply passage. An oblong cylinder-shaped portion that has a chamber is formed between the hydraulic fluid supply opening and the hydraulic fluid supply portion. Further, a volume-augmented chamber forming portion that has a volume-augmented chamber that is communicated with the chamber is disposed in this oblong cylinder-shaped portion. In that case, at least part of the volume-augmented chamber is positioned above a MAX line of the hydraulic fluid.

The invention belongs to the technical field of environmental geotechnics and discloses a mud high-pressure filtering and compressed dewatering testing cavity. The mud high-pressure filtering and compressed dewatering testing cavity comprises a force application pushrod, a top cover, a cylinder barrel, a piston, a lower porous plate, a base and a first water pressure transmitter, wherein the forceapplication pushrod is embedded inside a through hole formed in the top cover and can move axially; the top cover is detachably arranged on the top opening of the cylinder barrel in a sealed mode; the piston abuts against the inner wall of the cylinder barrel and is fixedly connected with the first end of the force application pushrod and driven by the force application push rod to move axially along the inner wall of the cylinder barrel; the base is arranged on the bottom opening in a sealed mode on the cylinder barrel; the lower porous plate is arranged in the lower portion of the inner cavity of the cylinder barrel and abuts against the base; the sensing end of the first water pressure transmitter is fixed inside the inner cavity of the cylinder barrel; the base is provided with a lower drainage channel and communicated with the liquid outlet of the lower porous plate. The mud high-pressure filtering and compressed dewatering testing cavity can in real time convert data of transmission pressure application change, liquid drainage and liquid pressure, thereby increasing diversity of testing data.