333 results about "Dispersion relation" patented technology

This invention pertains to the extraction of the slowness dispersion characteristics of acoustic waves received by an array of two or more sensors by the application of a continuous wavelet transform on the received array waveforms (data). This produces a time-frequency map of the data for each sensor that facilitates the separation of the propagating components thereon. Two different methods are described to achieve the dispersion extraction by exploiting the time frequency localization of the propagating mode and the continuity of the dispersion curve as a function of frequency. The first method uses some features on the modulus map such as the peak to determine the time locus of the energy of each mode as a function of frequency. The second method uses a new modified Radon transform applied to the coefficients of the time frequency representation of the waveform traces received by the aforementioned sensors. Both methods are appropriate for automated extraction of the dispersion estimates from the data without the need for expert user input or supervision

A process for the coating of the flow channels of a cylindrical, honeycomb form catalyst carrier with a dispersion coating through filling of the vertically oriented flow channels with a fill quantity of the coating dispersion through the bottom face of the catalyst carrier and subsequent downward emptying and clearance extraction of the flow channels, as well as drying and calcination of the catalyst carrier, by the following steps: a) filling of the flow channels with a fill quantity that is about 10% greater than the empty volume of the flow channels, so that the coating dispersion goes over the upper face of the catalyst carrier after completion of the filling cycle, b) removal of the excess coating dispersion at the top before emptying of the flow channels and c) emptying and clearance extraction of the flow channels through an extraction impulse, which is generated by connection of a vacuum tank with the bottom face of the catalyst carrier, whereby the time between the beginning of the fill cycle and the end of the emptying and clearance extraction amounts to no more than 5 seconds.

The present invention relates to a coated fiber based substrate comprising a dispersion coating wherein said dispersion coating comprises microfibrillated cellulose and colloidal particles of a polymer. The invention further relates to a package formed from said substrate, a dispersion coating and process for the production of mentioned substrate.

A method for determining a representation of an anisotropic earth formation is described, wherein the inversion step for generating the representation from recorded seismic data is performed using several values of a pre-defined anisotropy parameter addition to components of the moveout velocity. The anisotropy parameter is preferably introduced into the moveout equation or dispersion relation, which in turn is used in the inversion process. A more accurate representation of earth

The invention provides a preparation method for a coating anode material of a lithium battery. The preparation method comprises the following specific steps: (1) weighing a coating material and monomer sulfur; weighing the coating material and the monomer sulfur according to a mass ratio, wherein the mass ratio of the coating material to the monomer sulfur ranges from 1:1 to 1:100; (2) preparing a dispersion solution of the sulfur: dissolving the monomer sulfur into a sodium polyacrylate water solution with the mass percentage of 2%-10% at a room temperature to obtain the dispersion solution of the sulfur; (3) preparing a dispersion solution of the coating material: dissolving the coating material into a surfactant water solution at 20-45 DEG C to obtain the dispersion solution of the coating material; and (4) preparing the coating anode material of the lithium battery. According to the preparation method for the coating anode material of the lithium battery, self discharge of the battery is reduced effectively and the stability of the structure in a charging/discharging process of a sulfur electrode is kept; a sulfur active material prepared by the preparation method is used as a lithium-sulfur secondary battery anode material and the prepared lithium material has a high specific discharge capacity and a good circulating performance.

The present invention relates to fine and superfine cassiterite recovering technology. The whole production process of recovering cassiterite includes the following steps: collecting the fine grain ore slurry, dewatering to stabilize, floating all cassiterite of different sizes by means of proper amount of floating agent, dispersion dewatering, shaking table recovering large cassiterite, dispersion floating the desilting from dispersion dewatering, and depositing and dewatering the ultimate tin concentrate.

The invention discloses a patterned transparent electrode fabrication method. The method comprises the steps of (1) depositing a conductive nanoparticle dispersion solution on a porous filter membrane with a negative pattern mask to obtain a patterned transparent conductive film adhered on the porous filter membrane; and (2) removing the mask, transferring the patterned transparent conductive film on the porous filter membrane onto a transparent substrate, and removing the porous filter membrane to obtain the patterned transparent electrode; wherein the dispersion solution contains conductive nanoparticles 0.015wt% to 5wt%, dispersing agent 0.15wt% to 20wt%, and water in balance; and the dispersing agent is selected from arbitrary one or the combination of a surfactant, organic acid, high-molecular polysaccharide and DNA macromolecules. The method has the advantages of simple process, low cost and large material selection range, and can accurately design and control the formed pattern according to requirement.

The invention relates to a method for preparing a load type high-dispersion multi-component precious metal nanoparticle catalyst. The method comprises the steps of 1) under inert atmosphere, uniformly stirring a solvent and a surface active agent, then adding a precious metal precursor solution, rising the temperature, reacting for a certain period of time, cooling to the room temperature, adding normal hexane, and performing extraction layering; 2) uniformly mixing the obtained upper layer nanoparticle solution with a carrier, and stirring or performing ultrasonic treatment; and 3) centrifugating, washing and drying or baking the mixed solution to obtain the catalyst. For the precious metal catalyst, even under a relatively high carrying amount, relatively good precious metal nanoparticle dispersion degree can be still guaranteed; the particle sizes of the particles are uniformly distributed; the precious metal carrying amount is controlled easily and accurately; the particle sizes and the components of multi-component particles can be controlled; and the catalysis application range is wide. The process is simple; the preparation cost is low; the applicability is high; and load-type high-dispersion precious metal and the multi-component precious metal nanoparticle catalyst can be prepared in a large scale.

The invention provides a nonlinear optimization based time-space domain staggered grid finite difference method and device. The method includes: determining finite difference coefficients; optimizing the finite difference coefficients on the basis of time-space domain dispersion relation and a nonlinear inversion algorithm; utilizing the optimized finite difference coefficients to perform elastic wave forward modeling. By the method and device, the technical problems of high middle-high frequency dispersion and low simulation precision caused by the fact that a finite difference method of taylor series expansion and space domain dispersion relation is utilized to acquire the finite difference coefficients so as to perform elastic wave forward modeling are solved, dispersion of middle and high frequency is achieved, and technical effect of simulation precision is improved.

The invention belongs to the field of wave remote sensing technology, and particularly relates to a method for conducting X wave band navigation radar wave parameter inversion through a band-pass filter based on a novel wave dispersion relation, wherein sea clutter images are obtained through navigation radar so that wave parameter inversion can be conducted. The method comprises the steps that radar image data are collected; radar images are preprocessed; Fourier transform is conducted on an image sequence under a Cartesian coordinate system, so that a three-dimensional wave number frequency image spectrum of the radar images is obtained; wave spectrum information is extracted; wave information inversion is achieved. Influence on the dispersion relation by the ship speed is kept by the filter, the problem that the band pass of a traditional broadband-pass filter is increased along with increase of the movement speed is effectively solved, and therefore filtering can be conducted under the condition that a radar platform is moved along with movement of a ship. In band pass boundary derivation of the novel filter, an approximate value of any quantity is avoided, calculation errors are reduced, influence on the band pass boundary is avoided, band width calculation is more accurate, and wave inversion accuracy is improved.

The invention relates to a preparation method of a cobalt oxide/graphene composite nano material, which is characterized by comprising the following steps: (1) preparing a 0.01-1.00 mol/L cobalt nitrate-organic fuel mixed solution, wherein the mol ratio of organic fuel to metal ions is 0.9-2; (2) preparing a 0.1-1.0 mg/ml graphene oxide dispersion solution; (3) calculating the volumes of the mixed solution obtained in the step (1) and the graphene oxide dispersion solution obtained in the step (2) according to the mass ratio of cobalt oxide to graphene in the designed product and the required preparation amounts, and mixing the mixed solution and the graphene oxide dispersion solution by ultrasonic to obtain a dispersion solution for atomization; (4) filling the dispersion solution obtained in the step (3) into an ultrasonic atomization device, carrying the generated atomized liquid drops into a 500-1100 DEG C pipe furnace by argon or nitrogen gas at the flow rate of 0.3-1.2 L/minute, and initiating solution combustion reaction; and (5) collecting the solid reaction product. The invention has the advantages of shorter technical procedure, simple synthesis equipment and continuous preparation process, can directly obtain the final powder product by one step, and can easily implement industrialized preparation.

Slowness dispersion characteristics of multiple possibly interfering signals in broadband acoustic waves as received by an array of two or more sensors are extracted without using a physical model. The problem of dispersion extraction is mapped to the problem of reconstructing signals having a sparse representation in an appropriately chosen over-complete dictionary of basis elements. A sparsity penalized signal reconstruction algorithm is described where the sparsity constraints are implemented by imposing a l₁ norm type penalty. The candidate modes that are extracted are consolidated by means of a clustering algorithm to extract phase and group slowness estimates at a number of frequencies which are then used to reconstruct the desired dispersion curves. These estimates can be further refined by building time domain propagators when signals are known to be time compact, such as by using the continuous wavelet transform.

The invention relates to a black photo resist and a preparation method and a picture composition method thereof. The black photo resist comprises 5 to 45 weight percent of black pigment, 0.5 to 67 weight percent of dispersing agent, 0 to 5 weight percent of auxiliary dispersing agent, 0.05 to 30 weight percent of dispersion resin, 0.05 to 30 weight percent of alkaline soluble resin, 2 to 22 weight percent of unsaturated vinyl monomer, 0.05 to 10 weight percent of epoxy resin, 25 to 80 weight percent of organic solvent, 0.15 to 10 weight percent of photoinitiator and 0.01 to 2 weight percent of additive. The black photo resist has the advantages of small granularity, narrow particle size distribution range and high storage stability, can meet the requirement of material selection of a black matrix of an optical filter, and is favorable for improving the display quality of display products comprising the black matrix of the optical filter.

Provided are a graphene nanosheet dispersion and a preparation method therefor. In the dispersion, the graphene nanosheet has a thickness of 0.35 - 7 nm, and is dispersed in a solvent in the form of a single layer or multiple layers. The preparation method comprises the following steps: (1) mixing graphite with a solid polymer proportionally, and grinding mechanically to obtain a mixed powder of graphene nanosheets/solid polymer; (2) adding the mixed powder of graphene nanosheets/solid polymer into a solvent capable of dissolving the polymer, so as to obtain an intermediate of graphene nanosheet dispersion; and (3) removing the solid polymer dissolved in the solvent from the obtained intermediate of the dispersion, so as to obtain the graphene nanosheet dispersion. The polymer is used as a dispersion phase in the method and promotes the stripping of graphite during grinding so as to effectively inhibit the obtained graphene nanosheets from reaggregation. The method is simple and has a low cost.

A system and a method for generating terahertz (THz) radiation are provided. The system includes a photonic crystal structure comprising at least one nonlinear material that enables optical rectification. The photonic crystal structure is configured to have the suitable transverse dispersion relations and enhanced density photonic states so as to allow THz radiation to be emitted efficiently when an optical or near infrared pulse travels through the nonlinear part of the photonic crystal.

The invention relates to a method for measuring optical constants of a thin film with a non-uniform refractive index. The method comprises the following steps: perfomring spectral measurement on transmissivity and reflectivity of the thin film to obtain spectral measurement data; performing variable-angle ellipsometry on the thin film to obtain ellipsometric parameters; and fitting the spectral data and the ellipsometric parameters, matching with a corresponding dispersion relation, and working out the optical constants of the thin film by using a non-uniform model. On the basis of separate use of the photometry and the ellipsometry, respective advantages of the photometry and the ellipsometry are flexibly taken, high sensitivity of measuring optical parameters of a film layer by the ellipsometry and intuition of measuring data by the photometry are fully played, and the photometry and the ellipsometry are combined with each other to obtain high-precision analytical data of the optical constants, so that the reliance of the photometry on the thickness of the thin film is improved and the difficulty for model calculation by the ellipsometry is reduced.

The invention discloses a method and system for sea-clutter restraining and target detection in a sea-clutter background. The sea-clutter restraining method includes: performing two-dimensional Fourier transformation on a history plot of a one-dimensional range profile, which is detected by a sea-surface search radar in a real-time manner and obtaining a real-time-detection space-time dispersion relation and extracting real-time-detection speed parameters from the real-time-detection space-time dispersion relation; according to a linear relation between the real-time-detection speed parameters and intrinsic speed parameters, determining intrinsic speed parameters corresponding to the real-time-detection speed parameters and determining an intrinsic space-time diversion relation of sea clutters, which is based on the intrinsic-speed parameters; performing reconstruction through use of the determined intrinsic space-time diversion relation and obtaining an estimated history plot of the one-dimensional range profile of the sea clutters; and subtracting image data of the estimated history plot of the one-dimensional range profile of the sea clutters from image data of the real-time-detection history plot of the one-dimensional range profile and obtaining image data of a sea-clutter-restraining history plot of the one-dimensional range profile. Therefore, the sea flutters are restrained better and accuracy of target detection in the sea-clutter background is improved.

The invention discloses a logic device based on spin wave interference and a multiferroic material. The logic device comprises five functional zones, namely, a spin wave excitation zone, a spin wave frequency division zone, an electric field regulation and control zone, a spin wave interference zone, and a spin wave detection zone; the basic structure and shape of the logic device are achieved through a spin wave transmission medium; due to the dispersion relation of spin waves in the medium, the spin wave transmission direction and model change in case of an external magnetic field or an internal magnetism change of the medium. The logic device provided by the invention can be used for achieving information transmission and logic operation; the spin waves are based on electron spin, and a regulation and control voltage is based on an electric field, so that electron generation or hole movements are eliminated, and the joule heat produced by electric current and the problem of quiescent dissipation due to leak current are effectively avoided.