34 results about "Gadolinium oxysulfide" patented technology

A method is provided for improving the x-ray screen brightness of gadolinium oxysulfide x-ray phosphors. The method applies annealing and acid washing steps in a specific order following deagglomeration of the phosphor in order to ameliorate the loss of brightness caused by the deagglomeration.

The present invention relates a low-cost two-step-sintering preparation method of gadolinium oxysulfide (GOS with the chemical formula of Gd2O2S) scintillation ceramic doped with at least one element of Pr, Ce, Tb and Eu, and the method includes hot uniaxial pressing and hot isostatic-pressing secondary sintering.

The invention relates to a hot-pressing reaction sintering method for gadolinium oxysulfide scintillating ceramics, wherein the hot-pressing reaction sintering method includes the steps: Gd2O2SO4 and a reducing agent powder are mixed evenly to obtain a raw material powder, and the raw material powder is subjected to step-wise sintering, wherein the reducing agent includes activated carbon, graphene, coke and charcoal, the step-wise sintering comprises first-stage sintering at the temperature of 820-950 DEG C and the pressure of 10-75 MPa and second-stage sintering at the temperature of 1000-1500 DEG C and the pressure of 30-150 MPa, and an inert atmosphere, a reducing atmosphere or vacuum is maintained in the sintering process.

The invention relates to a reinforced concrete structure X-ray imaging detector, belongs to the field of reinforced concrete structure X-ray imaging detection, and concretely relates to reinforced concrete cast structure layer, beam, column and plate X-ray imaging detection. The reinforced concrete structure X-ray imaging detector comprises an X-ray source generator device, an X-ray source modulator outputs a controllable high-frequency power supply feedback sampling signal in order to make amount-adjustable X-ray be emitted from the X-ray source generator device and penetrate through a detected substance, a gadolinium oxysulfide amorphous silicon flat detector receives the obtained X-ray, converts the X-ray into a digital signal and transmits the digital signal to a computer, the computer acquires and displays the real image of the internal of the detected substance in order to accurately judge the crack, the cavity, the shape structure change and the substance density in the detected substance, and a magnetic positioning, receiving and emitting device controls the journey of a mobile track in order to realize synchronous motion, reach detection full-coverage rate and guarantee the operating safety.

The present disclosure is directed to a rapid process for the preparation of gadolinium oxysulfide having a general formula of Gd₂O₂S, referred to as GOS, scintillation ceramics by using the combination of spark plasma primary sintering (SPS) and hot isostatic pressing secondary sintering.

The invention provides a preparation method of gadolinium oxysulfide powder, which comprises the following steps: A) mixing Gd2O3, an activating agent, a fluxing agent and sulfur according to a stoichiometric ratio to obtain mixed powder; b) carrying out ball milling on the mixed powder and a mineralizing agent to obtain precursor powder; and C) calcining the precursor powder to obtain primary powder, and performing acid pickling and vacuum drying on the primary powder to obtain the gadolinium oxysulfide powder. The preparation method of the gadolinium oxysulfide powder provided by the invention is green and environment-friendly, and the gadolinium oxysulfide powder with fine and uniform particle size can be prepared.

The invention relates to a preparation method of a gadolinium oxysulfide (Gd2O2S) gold nanorod core-shell structure. The preparation method comprises the following steps: preparing seed crystals, preparing a growth solution, preparing gold nanorods and preparing the Gd2O2S gold nanorod core-shell structure (GNRs@Gd2O2S). The modified gold nanorod @ gadolinium oxysulfide (Gd2O2S) and the preparation method thereof have the characteristics as follows: the preparation method is simple and repeatable, the biocompatibility is good, and good light-heat conversion efficiency is achieved; besides, both magnetic resonance imaging (MRI) and photoacoustic imaging (PAI) can be carried out, the diagnosis and treatment of tumor are combined, and good biological-medical and cancer therapic application prospects are achieved.

A fluorescent screen is configured to convert an X-ray into visible light to one embodiment. The screen includes a gadolinium oxysulfide phosphor activated with praseodymium and cerium. The phosphor contains praseodymium having a concentration of 0.01 mass % or more and 0.3 mass % or less and cerium having a concentration of 5 ppm or more and 30 ppm or less. An average particle diameter of the phosphor is 10 [mu]m or more and 20 [mu]m or less. A weight per unit area of the phosphor is 270 mg/cm2 or more and 380 mg/cm2 or less.

The invention discloses a method for preparing gadolinium oxysulfide ceramic hollow microspheres, which comprises the following steps: adding additives into a water solvent, uniformly mixing to prepare a premixed solution, and the additives comprise a dispersing agent, a monomer, a cross-linking agent, a green body reinforcing agent, a closed pore forming agent and a sintering aid; carrying out ball milling on Gd2O2S ceramic powder and the premixed liquid to prepare Gd2O2S slurry with the solid content of 75-85%, adding an initiator and a catalyst, and uniformly mixing for later use; a semi-arc-shaped super-hydrophobic track coated with a super-hydrophobic film is manufactured, the track is arranged on an inclined rack, and a heating belt is attached to the lower portion of the inclined plane of the track; a dispensing machine needle head is selected to enable a titration needle cylinder to be located at the position 18-15 cm above the track, Gd2O2S ceramic slurry is injected into the titration needle cylinder, the inclined plane is controlled to be heated to 150-210 DEG C, the size of liquid drops is controlled to be 0.18-1 mm through the air inlet pressure of compressed air and the size of a needle hole, the liquid drops drop on the metal track coated with the super-hydrophobic film from the top end of the inclined plane, and the Gd2O2S ceramic slurry is obtained. The Gd2O2S microspheres roll downwards and are heated and cured into Gd2O2S microsphere blanks; and drying and degreasing the formed Gd2O2S ball blank, and sintering to obtain the Gd2O2S ceramic hollow microsphere.

The present invention provides a gadolinium oxysulfide sintered body having a high light output. The problem is resolved by a gadolinium oxysulfide sintered body in which the ratio of the light transmittance T₄₁₀ of 410 nm to the light transmittance T₅₁₂ of 512 nm (T₄₁₀/T₅₁₂) is from 0.31 to 0.61, or a gadolinium oxysulfide sintered body in which the ratio of the diffraction peak intensity I_y of a phase different from gadolinium oxysulfide appearing at 2θ=from 20 to 29° to the diffraction peak intensity (I_x) of (102) or (011) of gadolinium oxysulfide appearing at 2θ=30°±1° (I_y/I_x) is 0.1 or less in an XRD diffraction pattern and which contains one or more activators selected from the group consisting of praseodymium, terbium, and cerium.

An X-ray detector (6) of an embodiment is provided with a transmission-type fluorescence generation portion (11) provided on an incident portion (9a) of a detector body (9), and a reflection-type fluorescence generation portion (13) provided on a portion (9b) other than the incident portion (9a) of the detector body. The transmission-type fluorescence generation portion (11) and the reflection-type fluorescence generation portion (13) are each provided with an intensifying screen provided with a phosphor layer containing praseodymium-activated gadolinium oxysulfide phosphor particles, among which the percentage of particles having a particle diameter within plus or minus 30% of a median particle diameter is 45 vol% or more, and the filling percentage of which is 60 vol% or more, and/or an intensifying screen provided with a phosphor layer containing europium-activated barium chloride fluoride phosphor particles, among which the percentage of particles having a particle diameter within plus or minus 30% of a median particle diameter is 45 vol% or more, and the filling percentage of which is 45 vol% or more.

The invention discloses a regenerator and a refrigerating machine. The regenerator comprises a heat exchange cavity which is divided into a first filling area, a second filling area and a third filling area in the axis direction of the regenerator, wherein the first filling area is filled with lead balls; the second filling area is filled with holmium copper balls and gadolinium oxysulfide balls, and the diameters of the holmium copper balls are smaller than those of the gadolinium oxysulfide balls; and the third filling area is filled with gadolinium oxysulfide balls. According to the regenerator disclosed by the invention, by reasonably setting the distribution of the refrigerating medium and setting the components of the refrigerating medium, the temperature from a 10K temperature zone to a 4K temperature zone is divided into two stages, so that the refrigerating efficiency of the regenerator from the 10K temperature zone to the 4K temperature zone is improved.

The invention provides a preparation method of gadolinium oxysulfide powder and sparkling ceramics. The preparation method of Gd2O2S powder includes the following steps that Gd2O3, sulfuric acid and rare earth oxides are mixed and stirred to obtain precursor powder; the precursor powder is calcined at 700-800 DEG C; the well calcined precursor powder and a solid reducing agent are subjected to ball milling and mixed; the mixed powder is reduced in a reducing atmosphere, and (Gd1-XBX)2O2S powder is obtained, wherein B refers to one or more of Pr, Tb, Ce and Eu and X=0.005-0.15; ethyl alcohol isadded into the (Gd1-XBX)2O2S powder, pelleting is performed through a pelletizer after stirring, and the (Gd1-XBX)2O2S powder with the particle size more than 95% is obtained. A commercially feasiblecomplete method for preparing Gd2O2S powders, pre-pressing powders and sintering ceramics is provided, and the method has the advantages that the cost is low, batch manufacture is easy and stabilityand reliability are achieved.

The invention discloses a fluorescent screen for X ray detection. The fluorescent screen comprises a support layer and a fluorescent layer supported on the support layer; and the fluorescent layer contains gadolinium oxysulfide. Meanwhile, the invention also discloses a method for preparing a fluorescent screen. The fluorescent screen made of gadolinium oxysulfide can emit visible light after absorbing an X ray; and on the basis of cooperation with a photoelectric converter, photoelectric conversion of the X ray is realized. When the fluorescent screen is prepared by the preparation method, advantages of simple process and low cost are realized.

The invention discloses a medical nuclide imaging system and a medical nuclide imaging method based on photosensitive tights. The imaging system comprises an imaging darkroom, three CCD cameras, a control system, a lifting system and the photosensitive tights, wherein the photosensitive tights are prepared by uniformly mixing acrylic fibers and Gd2S2O (gadolinium oxysulfide) rare earth material. During the imaging process, a to-be-tested person receives intravenous injection of corresponding radionuclide, then enters the imaging darkroom for imaging at the proper moment, after lighting equipment inside the imaging darkroom is turned on, the to-be-tested person stands in an imaging area, and the three CCD cameras photograph the to-be-tested person; then the to-be-tested person stands still, the lighting equipment inside the imaging darkroom is turned off, the three CCD cameras collect fluorescence signals converted by the photosensitive tights and on the body surface of the to-be-tested person, and finally a fluorescence signal image and a picture image are displayed in a mixing manner. With the adoption of the medical nuclide imaging system and the medical nuclide imaging method, optical imaging of the medical radionuclide is realized, and the medical nuclide imaging system and the medical nuclide imaging method have the characteristics of whole body imaging, real-time imaging, simplicity and convenience in operation, low cost, and the like.