6 results about "Emission spectrum" patented technology

The invention discloses Mn<4+> doped fluoroaluminate red fluorescent powder as well as a preparation method and an application thereof. The method comprises steps as follows: hydrofluoric acid and water are added to a polytetrafluoroethylene container, K2MnF6 is added and stirred to be dissolved, and then KF is added; after KF is dissolved, K3AlF6 is added and continuously stirred to be completely dissolved, and then the mixture is continuously stirred for 30 min; the mixture is left to stand after stirring is stopped, suction filtration is performed, a filter cake is dried under the vacuum condition at the temperature of 70 DEG C, and the Mn<4+> doped fluoroaluminate red fluorescent powder is obtained. Compared with the prior art, the K3AlF6:Mn<4+> red fluorescent powder is synthesized in a hydrofluoric acid aqueous solution, and the diluted aqueous solution has a function of purifying the K3AlF6 phase; excessive KF.2H2O is added, so that the K3AlF6 phase is crystallized and separated to be purified in the aqueous solution; the obtained fluorescent powder has a narrow emission spectrum range, and the reabsorption phenomenon is effectively avoided; the phase of the synthesized fluorescent powder is pure, and the light emitting efficiency and collection rate are high; the color gamut range of a white light LED device packaged by the fluorescent powder is wide.

The invention provides an analysis device for detecting multiple anions simultaneously. The analysis device comprises an ion chromatography separating system and a liquid cathode glow discharge atomic emission spectroscopy detecting system. The ion chromatography separating system comprises a chromatographic pump for conveying a mobile phase, a leacheate generator, a six-way injection valve, a guard column, a separation column, an ion suppressor and a cation exchange column. The liquid cathode glow discharge atomic emission spectroscopy detecting system comprises a sample injection unit, a light source generating part generating glow discharge, a light split unit for carrying out light splitting treatment on a glow discharge emission spectrum, a detecting unit for detecting the emission spectrum obtained after light splitting treatment, and a data processing unit for analyzing data generated by the detecting unit. The ion chromatography separating system and the liquid cathode glow discharge atomic emission spectroscopy detecting system are combined for use, the analyzing process comprises separation of anions, conductive background suppression and ion conversion, the overall structure is simple, the performance is stable, and the price is low.

The invention relates to a measuring device for picosecond time resolution detection of a single photon weak signal. An optical pulse emission controller is connected with a microsecond optical pulseemitter, a picosecond pulse laser mode locker, a condenser, a sample bin, a fluorescence collector, an optical path transmitter, a color separation grating, an optical path aggregator, a light intensity detector, a preamplifier and a signal detection circuit in sequence; and the picosecond pulse laser mode locker is sequentially connected with the signal detection circuit. The measuring method comprises the following steps: an excitation light source emits a light beam to irradiate a sample to reach an electron excited state, and the device detects the time when a single fluorescence photon emitted by the sample reaches a signal detector to obtain the service life of the excited state; in addition, fluorescence emitted by excited state electrons returning to the ground state is fed back tothe light intensity detector through the optical path transmitter and is converted into an emission spectrum signal. According to the invention, the femtosecond oscillation stage is adopted to calibrate the time, and a standard is established for accurately measuring the technical performance of ultra-fast attenuation.

The invention discloses a determination method for contents of elemental silicon, manganese, phosphorus, nickel and chromium in weathering-resistant steel. The determination method comprises the following steps: step 1, preparation of standard stock solutions needed in a working curve; step 2, preparation of a working curve solution; step 2, preparation of a sample solution: a step of taking a to-be-determined steel sample and adding a mixed acid of hydrochloric acid and nitric acid to dissolve the sample so as to obtain the sample solution; and step 4, detection of the contents of silicon, manganese, phosphorus, nickel and chromium in the sample by using plasma atomic emission spectroscopy. The determination method provided by the invention can realize simultaneous determination of the five elements, i.e., silicon, manganese, phosphorus, nickel and chromium, by dissolving the sample once, so few chemical reagents are needed, pollution to the environment is small, labor cost is reduced, and an analysis speed is increased. The method is simple and rapid to operate and low in analysis cost; determination results of the method have good stability, reproducibility and accuracy; and the method can meet requirements of quantitative analysis detection of the contents of silicon, manganese, phosphorus, nickel and chromium in the weathering-resistant steel in daily life.

The invention discloses a light-emitting compound, a light-emitting layer material, an organic electroluminescent device and electronic equipment, and relates to the technical field of organic light-emitting materials, and the structural general formula of the light-emitting compound is as shown in the structural formula (1). The light-emitting compound is a benzidine derivative, ring formation modification is introduced to a benzidine structure with steric hindrance so that vibration of a donor structure can be restrained, then a rigid receptor is combined, a rigid D-A framework is formed, and the narrow emission spectrum characteristic can be easily achieved; besides, the benzidine structure is correspondingly modified, so that the energy level band gap and the light emitting color of the compound can be further regulated and controlled, and the commercial color standard is realized. Meanwhile, due to the large steric hindrance effect of the donor unit and the acceptor unit, accumulation of luminescent molecules can be avoided to a great extent, exciton quenching caused by the accumulation effect is inhibited, the luminous efficiency of the compound in an organic electroluminescent device is improved, and the photoelectric property requirement of a commercial organic electroluminescent device is met.

The invention belongs to the field of luminescent materials and relates to violet-LED excited blue fluorescent powder and a preparation method thereof. The chemical structural formula of the violet-LED excited blue fluorescent powder is M1-xMgSi5Al10O27: xEu<2+>, wherein M is one of Ca, Sr and Ba, x represents a molar coefficient, and x is greater than 0 and less than 1. The blue fluorescent powder has an extremely wide excitation peak, has strong absorption within the range of 250nm to 375nm, and can be well matched with a violet chip; the emission spectrum of the blue fluorescent powder is located within the range of 400nm to 540nm, and therefore, the blue fluorescent powder is high in luminous intensity and has a relatively high commercial application value; the preparation method of the blue fluorescent powder has the advantages of easily available raw material, simple process and low cost.