36 results about "Extinction spectrum" patented technology

A provided method for measuring key geometrical characteristics of nanometer particles comprises the following steps: loading the nanometer particles on a sample pool to obtain an extinction spectrum of the nanometer particles; arranging a mixed solution containing the nanometer particles in a referential sample pool and the sample pool for measuring to obtain a scattered spectrum of the nanometer particles; changing the concentration and the optical path length of metal nanometer particles, repeating the above steps, exporting measured data according with a linear response zone; pre-estimating the kinds of the key geometrical characteristics contained by the nanometer particles and the geometrical scale distribution scope; establishing databases of the relationship about the key geometrical characteristics with the extinction section coefficient and with the scattering cross-section coefficient; respectively converting the databases of the relationship about the key geometrical characteristics with the extinction cross-section coefficient and with the scattering section coefficient into matrixes, and converting the inverse problem into a linear equation group; and solving according to the databases of the extinction spectrum, the scattered spectrum and the extinction cross-section coefficient and the database of the scattering cross-section coefficient, to obtain the key geometrical characteristics of the nanometer particles.

Methods, systems and computer readable media for computing small particle size distributions of particles in a process stream comprising a sample dilute colloid. A reference matrix of pre-computed reference vectors is provided. Each reference vector represents a discrete particle size or particle size range of a particle size distribution of particles contained in a dilute colloid. Each reference vector represents a reference extinction spectrum over a predetermined wavelength range. A measurement vector representing a measured extinction spectrum of the sample particles in the sample colloid is provided, wherein the measured extinction spectrum has been spectrophotometrically measured over the wavelength range. The particle size distribution and particle concentrations of the particles in the sample colloid are determined using the reference matrix, the measurement vector and linear equations.

The invention relates to a preparation method of silver nanoparticle lattice with a wide plasmon resonant frequency regulation range. The method comprises the following steps: (a) covering an organic film on a substrate, fixing the substrate on a rotatable substrate holder with a light hole; (b) installing the substrate holder in a high vacuum settling chamber to ensure that the substrate on the substrate holder is in the center of the beam; (c) adopting the gas phase aggregation method to cluster a beam source and generate silver nanoparticles, using a nozzle to form a silver nanoparticle beam with high directionality and accurately controlled equivalent deposition rate; and (d) using the silver nanoparticle beam to deposit on the substrate, and accurately controlling the deposition of the nanoparticles to control the coverage of the silver nanoparticles on the substrate to be 5%-78%. Therefore, the interplanar distance of the deposited silver nanoparticles can be controlled, the plasmon resonant frequency can evolve continuously, and the changes of the plasmon resonant frequency is monitored through the in-situ extinction spectrum. The method of the invention is characterized in that the technology is simple, the cost is low, the regulation precision of the plasmon resonant frequency is high, the continuous regulation in the wide range is easy to realize, etc.

A spectrometer apparatus (1) is provided for measuring spectra of a liquid sample, such as a beverage such as wine. The apparatus (1) comprises an integrating cavity (3) comprising a reflective inner wall or walls (5), configured to receive a cuvette (7) containing the liquid sample within the integrating cavity (5). A combination of light inlet ports P1, P2 and light outlet ports P3, P4 are provided to receive light from at least one light source (9) and to deliver light to a spectrometer (11). A light path adjuster (13, 13B) is configured to selectively adjust a light path through the integrating cavity (5) such that at least two distinct light paths are provided; wherein when the light path adjuster (13, 13B) is in a first configuration, the apparatus (1) is in a transmission mode in which light from the light source follows a first light path (15) from the or one of the light inlet port(s) to the liquid sample such that the light from the light source irradiates the liquid sample directly before the light transmitted by the sample is transmitted through the or one of the light outlet port(s) and received by the spectrometer (11) for wavelength analysis of the light to provide an extinction spectrum of the liquid sample; and when the light path adjuster (13, 13B) is in a second configuration, the apparatus is in a diffusely reflecting mode in which light from the light source follows a second light path (17) from the or one of the inlet port(s) into the integrating cavity, is incident onto the reflective inner wall or walls of the integrating cavity and is diffusely reflected within the integrating cavity, such that the light from the light source irradiates the liquid sample before being transmitted through the or one of the light outlet port(s) and received by the spectrometer (11) for wavelength analysis of the light to provide an absorbance spectrum of the liquid sample contained in the liquid sample.

The invention discloses a symmetrical bow-shaped flexible metasurface sensor for biological cancer cell detection and application, the sensor comprises a substrate, symmetrical metal bow-shaped rings are etched on the substrate, and the substrate and the surface symmetrical metal bow-shaped rings form the metasurface sensor. Terahertz time-domain spectroscopy is used for testing a time-domain signal of the metasurface sensor, inner product operation is carried out on a Moire wavelet function and the time-domain signal obtained through testing through matlab programming, the Moire wavelet function is transversely translated to obtain time-domain information, the Moire wavelet function is longitudinally stretched to obtain frequency-domain information, and wavelet coefficients are extracted to obtain extinction spectrum intensity. And two-dimensional visual output of different concentrations and different biological samples which change in the time domain and the frequency domain at the same time is achieved by using a wavelet coefficient obtained by the inner product of the Moire wavelet function and the time domain signal. According to the invention, two-dimensional visual output of different biological samples with different concentrations is realized at the same time, multi-performance detection of the metasurface sensor is realized, and the limitation that the resolution of a flow cytometer is zero is broken through.