204 results about "Flux method" patented technology

The invention relates to an air-lift-type circulation photobioreactor. According to the photobioreactor, light sources are respectively installed at the wall surfaces of an outer cylinder and an inner flow guide cylinder of the reactor; air enters the reactor from an air distributor at the bottom of the circulation reactor, and drives a microalgae solution in the reactor to circulate, so that light generated by the light sources can irradiate an area between the inner sleeve cylinder and the outer sleeve cylinder, and the microalgae blink effect is fully utilized to promote the microalgae culture. According to the invention, the radial distance of inner and outer dual-surface irradiation reactor descending sections is determined by a dual-flux method, thereby designing and amplifying the air-lift-type circulation photobioreactor for irradiating the descending sections synchronously by the light sources inside and outside.

Method for measuring gaseous emissions and/or flux based on using a spectrometer instrument for receiving absorption spectra to detect and record, in a wavelength-resolved manner, the electromagnetic radiation which is coming directly from the sun. The instrument is arranged in such a way that the connecting line between the instrument and the sun transects a gas volume which constitutes all or part of the gas flow emitted from a source. The electromagnetic radiation which is recorded is used for calculating the gas concentration along the optical connecting line in the gas volume. The concentration which is obtained in this way, and which is integrated over the cross-sectional area traversed by the connecting line, is used, together with information on the speeds of the wind, the instrument and the gas-emitting source, to calculate the gas flow through the cross-sectional area which is traversed.

In the production of GaN through the flux method, deposition of miscellaneous crystals on the nitrogen-face of a GaN self-standing substrate and waste of raw materials are prevented. Four arrangements of crucibles and a GaN self-standing substrate are exemplified. In FIG. 1A, a nitrogen-face of a self-standing substrate comes into close contact with a sloped flat inner wall of a crucible. In FIG. 1B, a nitrogen-face of a self-standing substrate comes into close contact with a horizontally facing flat inner wall of a crucible, and the substrate is fixed by means of a jig. In FIG. 1C, a jig is provided on a flat bottom of a crucible, and two GaN self-standing substrates are fixed by means of the jig so that the nitrogen-faces of the substrates come into close contact with each other. In FIG. 1D, a jig is provided on a flat bottom of a crucible, and a GaN self-standing substrate is fixed on the jig so that the nitrogen-face of the substrate is covered with the jig. A flux mixture of molten gallium and sodium is charged into each crucible, and a GaN single crystal is grown on a gallium-face under pressurized nitrogen.

Growing method of alkali metals, chalcogene compounds crystal of gallium or indium, involves synthesis and crystal growth of a type alkali metals, chalcogene compounds crystal of gallium or indium ATrQ2(A=Li,Na,K,Rb,Cs;Tr=Ga,In;Q=S,Se,Te)the synthesis and crystal growth. The purpose of this invention is to combine the synthesis of alkali metals, chalcogene compounds crystal of gallium or indium ATrQ2 and growth technology of flux crystal. Choose alkaline earth metal chalcogene compounds, chalcogene compounds of gallium or indium and proper alkaline metal halide flux for raw materials, through reaction flux method to prepare and grow alkali metals, gallium or indium sulfur compounds ATrQ2 crystal.

The present invention is fluxing agent growth process of gallium phosphate crystal. Through using lithium carbonate and molybdenum oxide as flux, gallium oxide and ammonium dihydrogen phosphate as main material, mixing ammonium dihydrogen phosphate, gallium oxide, lithium carbonate and molybdenum oxide in the weight ratio of 1 to 1.23 to 1.12 to 6.57, setting the mixture in platinum crucible, heating to melt inside growth furnace and cooling to the temperature of 10-20 deg.c over the solution saturation point to obtain the mixed melt of gallium phosphate and the flux, introducing seed crystal into the growth furnace, lowering the temperature to 1-2 deg.c over the solution saturation point when the seed crystal begins to melt and rotating the seed crystal in 30 rpm for 24 hr, gallium phosphate crystal is grown. After lowering the temperature, the crystal is taken out of the solution. The process can eliminate water from the crystal and raise the piezoelectric performance of the crystal.

A cubic phase potassium sodium tantalum niobate crystal and a preparation method thereof relate to the potassium sodium tantalum niobate crystal and the preparation method thereof, which solve the problems that the existing potassium sodium tantalum niobate crystal products crack easily, and the paraelectric (cubic) phase potassium sodium tantalum niobate crystal has low optical quality, high sintering temperature, long time consumption, low yield and high cost. The chemical formula of the cubic phase potassium sodium tantalum niobate crystal is K1-yNayTa1-xNbxO3 or M:K1-yNayTa1-xNbxO3. The method comprises the following steps: (1) raw materials are weighed; (2) a potassium sodium tantalum niobate polycrystal is prepared; (3) the potassium sodium tantalum niobate polycrystal is cooled and seeded; (4) the cubic phase potassium sodium tantalum niobate crystal is obtained by a top seeded crystal flux method. The top seeded crystal flux method is utilized to realize the preparation of the cubic phase potassium sodium tantalum niobate crystal for the first time. The obtained product has the advantages of no crack, no stripe growth, high optical quality, even crystal components, and that the crystal has good optical property and good mechanical property. The preparation method has the advantages of simple process, short time consumption, low sintering temperature and low cost.

In the Na flux method, a target semiconductor layer is separated from a sapphire substrate of a template substrate. The template substrate formed of the sapphire substrate and a GaN layer is placed in a Ga—Na molten mixture. The temperature the molten mixture and the nitrogen pressure are adjusted to 850° C. and 2.5 MPa, respectively. Under the conditions, a part of the GaN layer is melted back until the surface of the sapphire substrate is exposed, so that the remaining portion of the GaN layer is left in the form of a plurality of upright columns. Then, the pressure is elevated to 3 MPa, whereby a target GaN layer is grown on the processed GaN layer. Through lowering temperature, stress due to the difference in linear expansion coefficient and lattice constant between sapphire and GaN is generated, to thereby generate cracks in the processed GaN layer. By virtue of the cracking, the target GaN layer is separated from the sapphire substrate.

The invention relates to a Zintl phase single crystal thermoelectric material and a preparation method thereof. The single crystal thermoelectric material comprises the following components: BaMn2Sb2, Ba1-xSrxMn2Sb2, Ba1-xYbxMn2Sb2, BaMn2-yZnySb2 and BaMn2Sb2-zGez (x is more than or equal to 0 and less than or equal to 1,y is more than or equal to 0 and less than or equal to 2, and z is more than or equal to 0 and less than or equal to 0.5) Ba0.75Sr0.25Mn2Sb2, Ba0.7Yb0.3Mn2Sb2, BaMn1.5Zn0.5Sb2 and BaMn2Sb1.5Ge0.5. The preparation method adopts a flux method. The method comprises the following steps: firstly weighing tin, manganese, antimony, barium and strontium, Yttrium, zinc or germanium for doping in a glove box, and adding the raw materials into a corundum crucible; then putting an inverted corundum crucible onto the corundum crucible containing the raw materials, filling a small amount of quartz wool between the two corundum crucibles, and putting the two corundum crucibles into a quartz tube; sealing the quartz tube through a preservative film and taking the quartz tube out of the glove box; carrying out vacuum pumping and repeatedly flushing the quartz tube with argon gas; and then sealing and welding the quartz tube and finally adopting a program temperature control furnace to prepare the single crystal. As the reaction temperature of the method is lower than that of a simple substance fusion method, the method is simpler and has less power consumption and lower cost.

The invention relates to a compound cesium lithium borate (CLBO) nonlinear optical crystal, which belongs to a trigonal system, and the chemical formula is Li4Cs3B7O14, the molecular weight is 726.14, the space group is P3121, the lattice parameters is as follows: a = 6.9313 (6), b = 6.9312 (6), c = 26.799 (4), Z = 3 and V = 1115.01 (19), and the mohs scale is 2 to 3; the compound grows crystals by using a flux growth method, and the CLBO nonlinear optical crystal prepared by using the method is used for preparing nonlinear optical devices. The compound is a melting compound prepared from different ingredients; and the prepared crystal is at least in a cm-level size, and has the advantages of quick preparation speed, simple operation, low cost, large size, wide nonopaque waveband, good mechanical performance, small possibility of crazing, stable physicochemical property, easy processing, and the like.

The invention relates to a neodymium-doped potassium gadolinium phosphate laser crystal of which the molecular formula is Nd:KGdP4O12, belonging to monoclinic systems. The neodymium-doped potassium gadolinium phosphate laser crystal has C2/c space group structure, wherein neodymium ions are used as doping ion to substitute the lattice position of gadolinium ions, and the doping content of the neodymium is 1-20at/%.The preparation method is implemented in a way that: a mixture of Gd2O3, Nd2O3, K2CO3 and NH4H2PO4 is used as a raw material, potassium metaphosphate obtained by reacting K2CO3 and NH4H2PO4 is used as a fluxing agent, and a self-flux method is utilized to prepare the neodymium-doped potassium gadolinium phosphate laser crystal.The laser crystal preparation technique is simple and easy to operate; the prepared crystal can not be easily cloven, has the advantages of of moderate hardness, favorable mechanical properties, favorable thermal properties and favorable optical spectral characteristics, and is used as a working substance in a solid laser; a flash lamp or LD is used as a pumping source to activate the laser output of which the wavelength is 1.06 mu m; and thus, the invention can be widely used in the fields of spectroscopy, biomedicine and military affairs.

The invention discloses an evaporator (1), which comprises a zigzag flat tube (2) arranged between each pair of adjacent straight tube parts (2a) of the flat tube (2) and brazed by flux corrugated fins (3) brazed thereon. The amount of flux remaining on the surface of the portion of the corrugated fin (3) that is not brazed to the straight pipe portion (2a) is 0.03-1 g/m2. The evaporator (1) is manufactured by applying 0.05-2.8g/m2 flux on the outer surface of the Z-shaped flat tube (2), and setting the corrugated fins (3) on the flat tube (2) ) between each pair of adjacent straight tube parts (2a), and the fins (3) are brazed on the flat tubes (2). The evaporator (1) can effectively suppress the emission of odor.

A plurality of protrusions 3 are provided on a c-face 2a of a sapphire body 2. An underlying layer 5 made of gallium nitride is then grown by vapor phase epitaxy process on the c-face 2a. A gallium nitride crystal layer 6 is then provided by flux method on the underlying layer 5. Each of the protrusions 3 has a shape of a hexagonal prism or a six-sided pyramid. Differences of growth rates of the gallium nitride crystal around the protrusions 3 are utilized to relax a stress between the sapphire body and gallium nitride crystal and to reduce cracks or fractures due to the stress.

A self-supporting substrate includes a first nitride layer grown by hydride vapor deposition method or ammonothermal method and comprising a nitride of one or more element selected from the group consisting of gallium, aluminum and indium; and a second nitride layer grown by a sodium flux method on the first nitride layer and comprising a nitride of one or more element selected from the group consisting of gallium, aluminum and indium. The first nitride layer includes a plurality of single crystal grains arranged therein and being extended between a pair of main faces of the first nitride layer. The second nitride layer includes a plurality of single crystal grains arranged therein and being extended between a pair of main faces of the second nitride layer. The first nitride layer has a thickness larger than a thickness of the second nitride layer.

The invention discloses a growth device for a sodium flux method gallium nitride single crystal. Structures such as a seed crystal clamp, a reaction container and a carrying platform are designed inside the device; in epitaxial growth of a single crystal, the seed crystal can be prevented from contacting a molten metal liquid with an over-saturated nitrogen atom concentration by reducing the height of the carrying platform, so that seed crystal decomposition is avoided, and surface quality degradation is prevented; a reaction cavity tray is driven by a motor connected with a transmission rod to rotate, so that the reaction container and a crucible inside are rotated relative to the seed crystal clamp, the molten metal liquid can be then stirred by a seed crystal clamping rod, the nitrogenatom concentration uniformity inside can be improved, the purpose of increasing the concentration of nitrogen atoms around the seed crystal can be achieved, and crystal nitrogen insufficiency can be avoided; due to adoption of a semi-sealed reaction container structure, escape of sodium steam in the crystal growth process can be reduced, external impurity atmospheres can be baffled, so that the metal sodium can play a role of a fluxing agent continuously, and a stable and pure growth condition can be provided for epitaxy of the gallium nitride single crystal.

Disclosed is a method for synthesizing a lithium transition metal oxide nanostructure for the cathode material LiCoO₂, by using a molten salts/hydroxides flux method, and a device thereof.