108results about How to "Half maximum width" patented technology

The invention provides a method for synthesizing ZnxCd1-xSe (x is more than or equal to 0 and less than or equal to 1) and ZnxCd1-xSe/ZnSe, ZnxCd1-xSe/ZnS and ZnxCd1-xSe core/shell structured semiconductor nanocrystals thereof by using long-chain fatty acid salts of cadmium and zinc as precursors of cadmium and zinc, which is the most economical and environment-friendly method for synthesizing high-quality ZnxCd1-xSe and related core/shell structured semiconductor nanocrystals thereof currently. The method avoids using tributylphosphine (TBP) or trioctylphosphine (TOP) dissolved elementary selenium as the precursor of selenium currently in the world, but adopts octadecylene (ODE) dissolved elementary selenium as the precursor of selenium; and the obtained nanocrystals have the quality equal to that of nanocrystals which are synthesized when the TBP or TOP dissolved selenium powder is used as the precursor of selenium. The method is called a phosphine-free method, has the advantages of simple synthesizing process, good repeatability, safety, environmental protection, no need of glove box, and cost conservation of over 60 percent. The synthesized ZnxCd1-xSe and related core/shell structured nanocrystals have a fluorescence range of between 400 and 650nm, and have the advantages of uniform particle size distribution, high efficiency of fluorescent quantum yield (40 to 70 percent) and narrow full width at half maximum. The method is also suitable for synthesizing the ZnxCd1-xS, HgxCd1-xSe, ZnxCd1-xTe nanocrystals and related core/shell structures thereof. More importantly, the method can synthesize high-quality nanocrsytals on a large scale, and has enormous application value both in laboratory synthesis and industrial synthesis.

The invention discloses a composite material and a preparation method thereof. The composite comprises perovskite quantum dots and polymers, and the perovskite quantum dots form coordination anchors with the polymers. Compared with the prior art, the composite material has the advantages of simple process, controllable reaction reactions, low cost and adaptation to continuous mass production of industrialization.

The invention relates to the technical field of organic electroluminescence, in particular to an organic compound, an application of the organic compound and an organic electroluminescence device comprising the organic compound. The general formula compound of the present invention has a structure represented by the following formula: wherein each of ring A, ring B, ring C and ring D independentlyrepresents any one of a C5-C20 monocyclic aromatic ring or fused aromatic ring, a C4-C20 monocyclic heterocyclic ring or fused heterocyclic ring; ring E represents a C5-C20 aromatic ring; Y1 and Y2 are respectively, independently and respectively N or B, and X1, X2, X3 and X4 are respectively, independently and respectively NR1, BR2, O or S. When the compound provided by the invention is used asthe luminescent material in an OLED device, excellent device performance and stability are shown. The invention also discloses an organic light-emitting device adopting the compound with the general formula.

The invention relates to a novel compound, an application thereof, and an organic electroluminescent device containing the compound. The compound has a structure as shown in the following formula, wherein Y1 and Y2 are respectively N or B; X1, X2, X3 and X4 are respectively NR1 or BR2; Ra, Rb, Rc and Rd each independently represent a mono-substituent to maximally allowable substituents; and Ra, Rb, Rc and Rd are independently selected from hydrogen, deuterium, or one of the following substituted or unsubstituted groups: a C1-C36 chain alkyl group; a C3-C36 naphthenic group, a C1-C10 alkoxyl group, halogen, cyano, nitro, hydroxyl, silyl, amino, substituted or unsubstituted C6-C30 aryl amino, substituted or unsubstituted C3-C30 heteroaryl amino, substituted or unsubstituted C6-C30 aryl and substituted or unsubstituted C3-C30 heteroaryl. When the compound is used as a luminescent material in an OLED device, the compound has an excellent device performance and high stability. The inventionalso discloses an organic light-emitting device adopting the compound with the general formula.

The invention relates to a pyrazoline-type hydrogen-bond self-assembly super-molecular polymer with blue-fluorescence property. The invention adopts an oligo-polyamide strip without secondary repulsion force as a hydrogen-bond bonding part and increases the number of hydrogen-bond donors and hydrogen-bond receptors to 8 from 4 so as to greatly improve the connection strength of the polymer. In addition, a pyrazoline derivative is introduced in a super-molecular polymer monomer as a blue-fluorescence unit to obtain a super-molecular blue-fluorescence polymer with a higher fluorescence quantum yield. The obtained six novel super-molecular polymer blue-fluorescence materials can emit pure-blue fluorescence in a solution state and have emission wavelengths of 440-455nm, semi-peak widths of 61-70nm and better color purity and can emit pure-blue fluorescence in a solid state and have emission wavelengths of 451-474nm, semi-peak widths of 71-79nm and better color purity.

The invention relates to the technical field of organic electroluminescence, and especially relates to an organic compound, application thereof, and an organic electroluminescence device containing the organic compound. The compound has a structure represented by formula (1) or formula (2) shown in the description. An aromatic ring or a heteroaromatic ring with a specific carbon atom number is used as a large-steric-hindrance protecting group to inhibit interaction between planar boron-containing/nitride-containing molecules, so that the compound has the advantages of narrow half-peak width, high fluorescence quantum yield, high fluorescence intensity and the like. Meanwhile, the glass transition temperature, the molecular thermal stability and the anti-aggregation quenching effect are high. The compound provided by the invention can be used as a luminescent layer doping material of an organic electroluminescent device, and can improve the luminescent color purity and prolong the service life of the device.

The invention relates to preparation of quantum dots, and discloses a preparation method of thick-shell core-shell quantum dots. A key step is that after quantum dot cores are prepared, an organic phosphine reagent is used for removing metal ions adsorbed on surfaces of the quantum dot cores, wherein the organic phosphine reagent is at least one of tributyl phosphine, triphenyl phosphine, tri-n-octyl phosphine, diphenyl phosphine, and dioctyl phosphine. The invention also discloses an LED containing the quantum dots. The invention provides a simple, convenient and economical method for preparing efficient green light-emitting core-shell quantum dots, and the method, based on an organic phosphine reagent assisted quantum dot extraction purification process, can be used for preparing thick-shell core-shell quantum dots which are controllable in wavelength, narrow in half band width, and high in quantum yield.

The invention provides a high-temperature-resistance quantum dot fluorescent material and a preparation method thereof. The preparation method comprises the following steps: preparing a Se solution; synthesizing quantum dots: putting a cadmium source, a zinc source, fatty acid and an organic solvent into a container to obtain a mixture, heating the mixture obtained in the (S210) to 80-110 DEG C, carrying out air exhausting for 30-40 minutes, heating to 280-310 DEG C, adding the Se solution, maintaining the temperature for a period of time, heating to 300-310 DEG C, adding the Se solution again, maintaining the temperature for 20-40 minutes, and cooling to the room temperature, so as to obtain a CdZnSe@ZnSe quantum dot stock solution; and purifying the obtained CdZnSe@ZnSe quantum dot stock solution, so as to obtain the high-temperature-resistance quantum dot fluorescent material. The high-temperature-resistance quantum dot fluorescent material prepared by virtue of the preparation method has excellent high temperature stability, can still present excellent fluorescence property at 310 DEG C, is narrow in half peak breadth and good in monodispersity and has good application prospects in the field of electro-optical display.

The invention discloses a fused ring compound, application thereof and an organic electroluminescent device containing the fused ring compound, and belongs to the technical field of semiconductors. The fused ring compound has a structure as shown in a formula (1) or a formula (2), an aromatic ring or a heteroaromatic ring with a specific carbon atom number is taken as a core and is fused with two same boron-containing groups, so that the fused ring compound has the advantages of narrow half-peak width, high fluorescence quantum yield, high fluorescence intensity and the like. Meanwhile, the compound has high glass transition temperature and molecular thermal stability, and has proper HOMO and LUMO energy levels. The compound provided by the invention can be used as a luminescent layer doping material of an organic electroluminescent device, and can improve the luminescent color purity and prolong the service life of the device.

The present invention relates to a method for preparing high-efficiency phosphor powder, and belongs to the field of LED inorganic light-emitting materials. The phosphor powder material has the following chemical formula: (Ca, Q) 1-y (Al, Si) 2 (N, T) 3: Ay, wherein Q including Li, Mg, Sr, Ba, Zn and Be, T comprises C, O , F, Cl and Br, A is an emission center element, and 0 <y<=0.5. The phosphor powder uses a porous halide as a fluxing agent, and the formula is MRb, wherein M includes Li, Na, K, Mg, Ca, Sr, Ba, Al, Eu, and NH4 +, R comprises F, Cl and Br, and 1<= b<=3. The method is capable of reducing single-phase (Ca, Q) 1-y (Al, Si) 2 (N, T) 3: Ay nitride generation temperature, crystallinity and morphology are improved to facilitate light absorption and transmitting, and light conversion efficiency of nitride red powder is improved.

The invention provides a white-light infrared up-conversion composite luminescent material with a core-shell structure. The composite material is characterized in that an infrared up-conversion nano-material is used as a core structure of the composite material; a quantum dot material with orange red fluorescence characteristics is used as a shell structure of the composite material; a chemical hydrothermal reaction is carried out so as to synthesize the white-light-emitting infrared up-conversion composite luminescent material with the core-shell structure; light with a wavelength of 980 nm is used as infrared excitation light; and the up-conversion nano-material is allowed to emit blue light under infrared excitation, and then quantum dots are allowed to emit orange red light under excitation of up-conversion blue light, so the infrared up-conversion composite luminescent material emitting white light is obtained. Since rare-earth up-conversion luminescent materials and semiconductor quantum dots are wide in photoluminescent band, high in color purity, brilliant in color, strong in light absorption capability, high in conversion efficiency, wide in the distribution area of emission wavelength, stable in physical and chemical performance, resistant to high temperature and capable of withstanding the action of large-power electron beams, high-energy radiation and strong ultraviolet light, the rare-earth up-conversion luminescent materials and semiconductor quantum dots are extensively applied to fields like illumination, displaying, development, medical radiography, detection and recording of radiation fields, etc., large in the scale of industrial production and consumer market and further applied to other emerging technical fields.

The present invention relates to a pharmacokinetic parameter estimation method based on the contrast agent enhancement curve, relates to the field of physiological parameter estimation, and discloses a regularized multi-blind-channel parameter estimation method. The method comprises the following steps: 1) using an arterial input function curve feature to automatically select the arterial input function curve; 2) using a contrast agent enhancement curve feature to cluster the global contrast agent enhancement curve to obtain three types of typical contrast agent enhancement curves; and 3) designing the regularized multi-blind-channel parameter estimation method according to the three typical contrast agent enhancement curves obtained in step 2), and estimating a pharmacokinetic parameter inverse flow coefficient; and 4) using the two-compartment model to estimate other pharmacokinetic parameters of vascular permeability, space volume fraction, and vascular volume fraction.

The invention discloses a quantum dot synthesis method. The synthesis method comprises the steps that a CdZnSe quantum dot serving as a nucleus is provided; a mixed reaction system containing the CdZnSe quantum dot, a cadmium source, a zinc source and a sulfur source reacts, and a CdZnS transition layer is formed on the CdZnSe quantum dot, wherein the zinc source comprises a precursor obtained byshort chain zinc fatty acid and amine which react under activation of a phosphine source. Accordingly, by means of the zinc source high in activity, the phenomenon that CdS is generated simply, so that the quantum dot efficiency is low can be avoided, the activity difference among Cd, Zn and S can be reduced, the quantum dot internal defects brought by the lattice parameter difference are reduced,and the quantum dot efficiency is improved. The obtained quantum dots are high in absorbance, high in luminous efficiency, uniform in size, good in monodispersion and narrow in half peak width.

A luminescent material having a polycyclic ligand is disclosed. The luminescent material is a metal complex with a polycyclic ligand, and can be used as a luminescent material in an electroluminescent device. The novel metal complexes can better adjust the light emitting color of a device, lower the driving voltage of the device or keep a low voltage level, improve the efficiency of the device, greatly prolong the service life of the device and provide better performance of the device while keeping very narrow half-peak width. An electroluminescent device and a compound combination are also disclosed.

The invention relates to design synthesis and application of a near-infrared two-window fluorescence probe based on Aza-BODIPY, and belongs to the field of organic fluorescence probes. A near-infraredtwo-area dyestuff (NIR-II, 1000-1700nm) has a long emission wavelength and less light scattering and tissue autofluorescence interference so as to obtain better resolution ratio and imaging depth inbioimaging. An Aza-BODIPY fluorescent dye has a longer absorption emission wavelength, a narrower peak width at half height and a larger molar extinction coefficient, and is widely applied to the fields such as photodynamic therapy. The structural formula of the near-infrared two-window fluorescence probe designed and synthesized by the invention is as shown in the figure (I). According to the probe, electron-donating group julolidine is introduced onto the classic Aza-BODIPY structure, and the molecular rigidity is improved. The probe has excellent light stability and a capacity of resistingdisturbance. The probe successfully realizes near-infrared two-window imaging during the mice imaging experiment.

The invention discloses a preparation method of quantum dots, wherein the preparation method comprises the steps: preparing ZnCdSe seed crystals, growing a ZnSe transition layer on the ZnCdSe seed crystals, and sequentially coating the ZnSe transition layer with a ZnSe shell layer and a ZnS shell layer. The invention also discloses the quantum dots prepared by the preparation method. Through the arrangement of the ZnSe transition layer, the relationship between a core and the shell layers is consolidated, the transition between the core and each shell layer is effectively controlled, and the defects between crystal lattices are reduced; the formation of other seed crystals in the quantum dots is inhibited through fatty acid so as to control the components, size and uniformity of the seed crystals of the quantum dots, anions are supplemented to carry out growth nucleation of the seed crystals, a quantum dot core structure with the ZnSe transition layer on the surface is formed, and then epitaxial growth of the ZnSe shell layer and the ZnS shell layer are sequentially carried out; lattice stress between components of the mixed crystal structure core and lattice stress between the core and the shell are reduced, and the prepared quantum dots are adjustable in peak position in visible light, narrow in half-peak width and high in quantum efficiency.

The invention belongs to the technical field of OLED, and provides a compound with a structure shown in a formula (1), wherein D represents an electron donating group containing a nitrogen atom and isconnected to a benzene ring through the nitrogen atom, and A represents an electron accepting group containing a boron atom and is connected to the benzene ring through the boron atom; m and n are respectively selected from 1, 2 and 3; and R11, R12, R13 and R14 are respectively and independently selected from a hydrogen atom, an alkyl group, an alkoxy group, a cyano group, a trifluoromethyl group, the electron accepting group A' or the electron donating group D' containing the nitrogen atom. The compound adopts biphenyl as a connecting unit between the electron donating group D and the electron receiving group A, the D and the A achieve effective separation of HOMO and LUMO at different positions of molecules, and two physical processes of intramolecular charge transfer and space charge transfer can be simultaneously formed in the same molecule through connection of the biphenyl between the D and the A units, so that absorption of the molecules to light is improved, and the oscillatorstrength of the molecules is improved.

The invention relates to a preparation method of cadmium telluride quantum dots; the preparation method comprises the steps: selecting a tellurium elementary substance as a tellurium source, cadmium chloride as a cadmium source and water as a solvent, and preparing a tellurium precursor solution under a condition of anaerobic heating; and after mixing of the tellurium and cadmium precursor solutions, carrying out a hydrothermal reaction in a reaction kettle to prepare the cadmium telluride quantum dots. The selected raw materials and solvent are wide in sources, low in cost and friendly to the environment; the reaction conditions are mild and are easy to control, and the reaction time can be greatly shortened; the obtained cadmium telluride quantum dots have the advantages of good water solubility and high fluorescent quantum yield; the method is simple, convenient and fast, also can be used for large-scale preparation, and provides a new economical and fast approach for synthesis of the high-quality cadmium telluride quantum dots.

The invention discloses a white light LED packaging structure and packaging method. The packaging structure comprises a blue light LED chip, a packaging substrate, a light-transmitting carrier, a multilayer-color quantum dot coating layer and a polysiloxane packaging layer, wherein the packaging substrate is used for fixing the blue light LED chip; the packaging substrate comprises a base and a surrounding baffle arranged on the periphery of the base; the blue light LED chip is fixed on the base; the light-transmitting carrier is arranged in the packaging substrate and above the blue light LEDchip; the multilayer-color quantum dot coating layer is arranged on the surface of the light-transmitting carrier; and the polysiloxane packaging layer is arranged on the surface of a protection layer. By virtue of the packaging structure, multi-color quantum dots are mixed to form a warm white light LED which is low in color temperature, high in visual effect and stable.

The invention discloses a photonic crystal preparation method. The photonic crystal preparation method comprises providing emulsion containing mono-dispersed particles, a surfactant and a solvent; applying the emulsion to a surface, of a substrate, where the photonic crystal needs to be formed to form a liquid pattern with the contact angle between the surface, of the substrate, where the photonic crystal needs to be formed ranging from 30 degrees to 120 degrees; and drying the substrate with the liquid pattern to obtain the photonic crystal. By means of the drying temperature and the drying time, Pe satisfies the formula 2<Pe<10 or 0<Pe<0.4, and Pe=(3h<2>[eta]r/t<f><2>kTt)<1/2>. The photonic crystal preparation method is low in cost and high in preparation efficiency, in the reflection spectrum of the prepared photonic crystal pattern membrane, the half-peak width is reduced and can reach to 30-60nm, the obtained photonic crystal pattern membrane is flatter in surface and higher in assembly quality, and is brighter in color accordingly; and a thinner photonic crystal pattern membrane can be obtained at the same time. The photonic crystal preparation method is high in applicability, and is suitable for a plurality of substrates and a plurality of preparation techniques.