30results about How to "Little change in resistivity" patented technology

The present invention discloses a graphene-sulfur composite electrode material, a preparation method and an application thereof, and belongs to the field of electrochemical batteries. According to the graphene-sulfur composite electrode material, a uniformly-dispersed graphene oxide aqueous solution, an organic solution of sulfur, and a miscible solvent are subjected to mixing stirring, and then are subjected to a hydrothermal reaction to form a three-dimensional macroscopic body structure with sulfur nanoparticles uniformly distributed and anchored on the fibrous graphene surface, and low temperature freeze-drying is performed to obtain the graphene-sulfur composite material. According to the present invention, the electrode material is the microcosmic structure with sulfur nanoparticles uniformly anchored on the interconnected fibrous graphene surface; and according to the battery design, after the graphene-sulfur material is cut to obtain the corresponding thickness, the obtained material is pressed and then can be directly used as the lithium-sulfur battery positive electrode with no metal current collector, no conductive agent and no adhesive.

A single crystal silicon wafer for use in the production of insulated gate bipolar transistors is made of single crystal silicon grown by the Czochralski method and has a gate oxide with a film thickness of from 50 to 150 nm. The wafer has an interstitial oxygen concentration of at most 7.0×10¹⁷ atoms/cm³, a resistivity variation within the plane of the wafer of at most 5% and, letting t_ox (cm) be the gate oxide film thickness and S (cm²) be the electrode surface area when determining the TZDB pass ratio, a density d (cm⁻³) of crystal originated particles (COP) having a size at least twice the gate oxide film thickness which satisfies the formula d≦−ln(0.9)/(S·t_ox/2). The wafers have an increased production yield and a small resistivity variation.

The invention relates to a crystal material with a bigger size, which is manufactured by using a seed crystal induction vertical directional solidification casting method, in particular to a polycrystal or monocrystal material suitable for photoelectric application, such as silicon or silicon germanium. A traditional seed crystal used for casting a silicon crystal has a bigger size and higher consumption, thus, the invention provides a seed crystal with a smaller size and lower consumption, a method of casting a polycrystal or a monocrystal with the bigger size by using the seed crystal and the directional solidification method, the crystal material obtained by adopting the method, including a semiconductor crystal, and an application of the seed crystal in manufacturing semiconductor devices.

The invention generally relates to a vertical directional solidification casting method using seed crystal induction, which is used for manufacturing a crystal material with a reserved crystal orientation and comprises a polycrystal material and a monocrystal material. When a traditional method for casting the crystal by using the seed crystal induction is used for producing the crystal with a bigger size, the problems that the seed crystal consumption is high, a mixed crystal is easy to generate, the internal stress is high, the monocrystal material is hard to obtain or the expected quality requirement is hard to reach and the like exist. The problems are solved by the invention through providing a gradually-changed crystal growth area of which the horizontal cross section is gradually increased, thereby, a good crystal growth effect is obtained, and the obtained cast monocrystal or polycrystal material, such as silicon or silicon germanium, has fewer defects, high quality and a good performance, and is especially suitable for the application of the semiconductor field and the photovoltaic field.

The present invention relates to a new type conductive paint and its preparation method. Said conductive paint is formed from film-forming material, conductive powder, coupling agent, diluent and adjuvant. The resistivity of paint film formed by utilizing said conductive paint is in the range of 0.38-0.65 ohm.cm.

A carrier core material for an electrophotographic developer including Li ferrite, maghemite, and Fe₃O₄, wherein a part thereof is substituted with Mn, Li content is 1 to 2.5% by weight, Mn content is 2 to 7.5% by weight, and silicon content is 25 to 10,000 ppm, the following equation (1) is satisfied when respective integrated strengths of spinel crystal structure (110), (210), (211), and (311) faces in X-ray diffraction are respectively I₁₁₀, I₂₁₀, I₂₁₁, and I₃₁₁, a resistivity R₅₀ of 50 V across a 6.5 mm gap is 5×10⁷ to 7×10⁸Ω, and a resistivity R₁₀₀₀ of V across a 6.5 mm gap is 1×10⁷ to 8×10⁸Ω.

2<100×(I₁₁₀+I₂₁₀+I₂₁₁)/I₃₁₁<14   (1)

The invention relates to a copper particle, a preparation method thereof, paste for forming an electric-conductive film, and objects, and aims to provide the copper particle which causes low degradation on electrical resistivity of the electric-conductive film at high temperature and humidity. The copper particle has a surface to which fatty acid and/or fatty acid salt is bonded. The bonding status of the fatty acid and/or fatty acid salt is described as follows: through diffused reflection IR detection, peak intensity (P1) at 1530/cm to the peak intensity (P2) at 2930/cm is P1/P2 = 0.15-0.45.

The invention belongs to the technical field of aluminum electrolytic capacitors, and particularly relates to an electrolyte for an ultralow-temperature aluminum electrolytic capacitor and a preparation method of the electrolyte. The electrolyte for the ultralow-temperature aluminum electrolytic capacitor comprises the following raw materials in percentage by mass: 40-50% of a first solvent, 20-30% of a second solvent, 5-10% of a third solvent, 1-15% of a solute and 0.5-5% of an additive. The additive comprises one or more of a hydrogen elimination agent and a high-temperature stabilizer, theelectrolyte is not frozen at the ultralow temperature and is small in resistivity change, the produced aluminum electrolytic capacitor can be normally used at the temperature ranging from-55 DEG C to105 DEG C, sealing rubber of the aluminum electrolytic capacitor is not corroded, the sealing performance is good, the service life is more stable, extra materials and process cost do not need to be increased, and the electrolyte is suitable for large-batch production and use.

Use of a composition comprising finely divided particles of (a) an electrically-conductive material; (b) one or more inorganic binders; and (c) one or more metal(s) selected from cobalt, nickel, iron and bismuth, wherein components (a), (b) and (c) are dispersed in a liquid vehicle, in the manufacture of an electrically-conductive pattern on a substrate for the purpose of increasing the resistivity of said electrically-conductive pattern.

A liquid crystal composition of the present invention has a liquid phase over a wide temperature range, low viscosity, good solubility at a low temperature, high resistivity and voltage holding ratio, and stability to heat and light, and can thus provide, in high yield, a liquid crystal display device having good display quality and causing little display defects such as image sticking, dropping marks, and the like. A liquid crystal display device using the liquid crystal composition of the present invention is useful, particularly useful for a liquid crystal display device for active matrix driving, because both fast response and suppression of display defects are achieved, and the liquid crystal display device can be applied to a liquid crystal display device for a VA mode, a PSVA mode, or a TN mode.

The invention discloses a heat-resisting electric conduction metal paste and a preparing method thereof. The heat-resisting electric conduction metal paste comprises the raw materials, by weight, 20-30 parts of tricresyl phosphate, 12-16 parts of titanium dioxide, 2-15 parts of propylene glycol, 10-13 parts of trichloroethane, 1-10 parts of Freon-11, 2-16 parts of calcium oxide, 6-10 parts of benzoyl peroxide, 18-20 parts of potassium peroxodisulfate and 20-30 parts of aluminium stearate. The electrical resistivity of the electric conduction metal paste prepared through the method is small, the electrical resistivity is only 1.8-1.9 omega*cm at the normal temperature, the change of the electrical resistivity under the high temperature condition is small, and the heat-resisting electric conduction metal paste has good electrical conductivity and heat resistance.

The invention provides an oxidation resistant copper-based electrically conductive paste and a preparation method thereof. the method comprises the following steps: (1) copper powder is treated with an aniline ethanol solution to prepare polyaniline-modified copper powder; (2) a hydrochloric acid solution of ammonium persulfate is added to a solution prepared in step (1) under the conditions of anice bath; after stirring reaction is performed, precipitate in a reaction system is intercepted via suction filtration, the precipitate is resuspended after being washed with an ethanol solution, anda mixture A is prepared; (3) a surface of a product obtained in step (2) is modified with a silver layer; (4) an organic binder is prepared; (5) composite copper powder and the organic binder prepared in step (3) are processed to prepare and obtain an oxidation resistant copper-based electrically conductive paste. The electrically conductive paste prepared in the invention is high in adhesive capability, low in electrical resistivity and high in antioxidation resistance. Thus, the electrically conductive paste is of great practical value when being applied to electrodes of a solar cell.

There is provided a liquid crystal composition containing any one or two or more of compounds represented by general formula (i) below and any one or two or more of compounds represented by general formula (ii) below.

The invention discloses a two-dimensional lamellar phase enhanced silver-based electric contact material and a preparation method thereof, and relates to the technical field of metal-based composite materials. The two-dimensional lamellar phase enhanced silver-based electric contact material adopts a two-dimensional lamellar layer rich in functional groups on the surface as a reinforcing phase, and silver ions coat a matrix in an electrostatic adsorption self-assembly and precipitation manner due to the polarity of the functional groups on the surface, so that the matrix and the reinforcing phase are mixed at a molecular level, and the interface two-phase wetting effect is better. Compared with metal silver, the hardness of the silver-based electric contact material obtained through the method is improved, and meanwhile the resistivity change is small.