119 results about "Tetravalence" patented technology

A complex fluoride A2MF6 wherein M is a tetravalent element Si, Ti, Zr, Hf, Ge or Sn, A is an alkali metal Li, Na, K, Rb or Cs is prepared by providing a first solution containing a fluoride of M, providing a second solution containing a compound of A and / or the compound of A in solid form, mixing the first solution with the second solution and / or the solid for reacting the fluoride of M with the compound of A, and recovering the resulting solid product via solid-liquid separation.

A phosphor (A) comprising a host material composed of a compound having a garnet crystal structure represented by the general formula (I):M1aM2bM3cOd  (I)(wherein M1 is a divalent metal element, M2 is a trivalent metal element, M3 is a tetravalent metal element containing at least Si, a is the number of 2.7 to 3.3, b is the number of 1.8 to 2.2, c is the number of 2.7 to 3.3, and d is the number of 11.0 to 13.0), and a luminescent center ion incorporated in the host material; a light emitting device (B) comprising the phosphor as a wavelength conversion material and a semiconductor light emitting element capable of emitting a light in the range of from ultraviolet light to visible light; and a display (C) and a lighting system (D) using the light emitting device (B) as a light source. The above phosphor can be readily produced, and can provide a light emitting device having a high color rendering property.

A phosphor including a main production phase of a phosphor expressed by a composition formula of MmAaBbOoNn:Zz (where an element M is one or more bivalent elements, an element A is one or more trivalent elements, an element B is one or more tetravalent elements, O is oxygen, N is nitrogen, an element Z is an activator, n=2 / 3m+a+4 / 3b−2 / 3o, m / (a+b)≧1 / 2, (o+n) / (a+b)>4 / 3, wherein m=a=b=1 and o and n is not 0). A phosphor including 24 wt % to 30 wt % of Ca (calcium), 17 wt % to 21 wt % of Al (aluminum), 18 wt % to 22 wt % of Si (silicon), 1 wt % to 15 wt % of oxygen, 15 wt % to 33 wt % of nitrogen and 0.01 wt % to 10 wt % of Eu (europium), wherein an emission maximum in an emission spectrum is in a range of 600 nm to 660 nm; and wherein color chromaticity x of light emission is in a range of 0.5 to 0.7, and color chromaticity y of the light emission is in a range of 0.3 to 0.5.

This disclosure provides a method of preparing a crystalline molecular sieve comprising: (a) providing a reaction mixture comprising at least one source of ions of tetravalent element Y, at least one source of alkali metal hydroxide, water, optionally at least one seed crystal, and optionally at least one source of ions of trivalent element X, the reaction mixture having the following molar composition:Y:X2=2 to infinity, preferably from about 2 to about 1000,OH−:Y=0.001 to 2, preferably from 0.1 to 1,M+:Y=0.001 to 2, preferably from 0.01 to 2wherein M is an alkali metal and the amount of water is at least sufficient to permit extrusion of the reaction mixture, wherein the reaction mixture is substantially free of crystalline molecular sieve; (b) extruding the reaction mixture to form a pre-formed extrudate; and (c) crystallizing the pre-formed extrudate in a liquid medium comprising water under liquid phase crystallization conditions to form a crystallized extrudate having the crystalline molecular sieve.

An oxynitride piezoelectric material, which exhibits ferroelectricity and has good piezoelectric properties, and a method of producing the oxynitride piezoelectric material. The oxynitride piezoelectric material includes a tetragonal perovskite-type oxynitride represented by the following general formula (1):A1−xBix+δ1B1−yB′y+δ2O3−zNz  (1),where A represents a divalent element, B and B′ each represent a tetravalent element, x represents a numerical value of 0.35 or more to 0.6 or less, y represents a numerical value of 0.35 or more to 0.6 or less, z represents a numerical value of 0.35 or more to 0.6 or less, and δ1 and δ2 each represent a numerical value of −0.2 or more to 0.2 or less, in which the A includes at least one kind selected from Ba, Sr, and Ca and the B and the B′ each include at least one kind selected from Ti, Zr, Hf, Si, Ge, and Sn.

The invention belongs to the technical field of inorganic materials, and in particular discloses MTW zeolite with a novel structure and a preparation method thereof. The method adopts a hydro-thermal synthesis method and comprises the following steps: mixing a silicon source, an aluminum source, an alkali source, an organic template and a water phase, and stirring to be a gel mixture as a raw material for synthesizing the MTW zeolite. The MTW zeolite with the novel structure has the chemical composition of TO2:aY2O3:bM2 / nO, wherein T represents at least one quadrivalent element, Y represents at least one trivalent element, M represents at least one alkali metal (or) alkaline-earth metal element and has the valence state of n, a and b respectively represent the mole numbers of T2O3 and M2 / nO, a ranges from 0 to 1, and b ranges from 0 to 0.8. The MTE zeolite prepared by using the method is tidy in morphology and uniform in crystal granule; compared with the conventional disordered MTW zeolite, the MTE zeolite has the advantages of fixed mass transfer orientation, high activity, high mechanical strength and the like, and can be widely applied to the chemical industry.

The invention relates to a method for separating and determining <238-240>Pu, <241>Am and <90>Sr in a low-radioactivity sample, which comprises the following steps: (1) sample pretreatment; (2) separation and enrichment of <238-240>Pu, <241>Am and <90>Sr: after ascorbic acid and sodium nitrite are added into a solution obtained in step (1) to regulate the valence state of plutonium into tetravalence, the solution passes through a TEVA, TRU and SR tandem extraction chromatography resin column, and the flow velocity is kept at 1mL / min to 1.2mL / min; at the moment, <238-240>Pu is adsorbed on the TEVA column, <241>Am is adsorbed on the TRU column, and <90>Sr is adsorbed on the SR column; 20mL to 25mL of hydrochloric acid solution which is 0.02mol / L is used for eluting <238-240>Pu on the TEVA column, 15mL to 20mL of hydrochloric acid solution which is 3.0mol / L is used for eluting <241>Am on the TRU column, and 15mL to 20mL of nitric acid solution which is 0.01mol / L is used for eluting <90>Sron the SR column; (3) determination of <238-240>Pu, <241>Am and <90>Sr: a cerium fluoride micro-deposition method is adopted to prepare an Alpha source, and the <238-240>Pu eluent and the <241>Am eluent are measured on the Alpha energy spectrum; the <90>Sr eluent is placed for 14 days, and after <90>Sr<-><90>Y is balanced, determination is carried out by the Cerenkov counting method. The analysismethod can be adopted to separate and enrich Pu, <241>Am and <90>Sr in a sample, and the period of analyzing Pu, <241>Am and <90>Sr is shortened.

The invention discloses an anion valence-varying layer oxide material, and a preparation method and application thereof. The chemical formula of the material is: Naa[LibMncMd]O2+[beta]; M is an element which is doped and substituted for a transition metal site; a, b, c , d and [beta] are the mole percentages of the corresponding elements respectively; the relationship between a, b, c, d and [beta]satisfies the formula: b+c+d=1, and a+b+4c+md=2(2+[beta]); 0.6<=a<=1, 0<=b<=0.4, 0.5<=c<=0.8, 0<=d<=0.3, and -0.02<=[beta]<=0.02; m is the valence state of M; and the space group of materials is P63 / mmc or R-3m, the corresponding structure is P2 phase or P3 phase, and the anion valence-varying layer oxide material is used for the positive electrode active material of sodium ion secondary battery.When charging is performed in the first week, the lattice oxygen ion is converted from a negative bivalence to a higher valence state, electrons are completely provided by the oxygen ions to achieveactivation of the material; when discharge is performed in the first week, the oxygen ions losing electrons regain electrons from the high valence state to the negative bivalence, and the manganese metal is converted from a tetravalence to a tervalence, and the charging and discharging process after two weeks has the valence varying of the oxygen ions and the valence varying of the manganese.

A method of manufacturing a molecular sieve of the MCM-22 family, said method comprising the steps of (a) providing a mixture comprising at least one source of ions of tetravalent element, at least one source of alkali metal hydroxide, at least one directing-agent (R), water, and optionally at least one source of ions of trivalent element, said mixture having the following mole composition:Y:X2 =10 to infinityH2O:Y =1 to 20OH−:Y =0.001 to 2M+:Y =0.001 to 2R:Y =0.001 to 0.34wherein Y is a tetravalent element, X is a trivalent element, M is an alkali metal; (b) treating said mixture at crystallization conditions for less than 72 hr to form a treated mixture having said molecular sieve, wherein said crystallization conditions comprise a temperature in the range of from about 160° C. to about 250° C.; and (c) recovering said molecular sieve.

The invention discloses a tetravalence metal-substituted silicoaluminophosphate molecular sieve. In a molecular sieve framework, metal elements (Me) substituting silicon-aluminum comprise Ti, Zr, Sn,Ge, Hf, Nb and the like, optimally comprise Ti, Zr, Sn and Ge, and further optimally comprise Ti and Zr. An initial gel is firstly prepared and aged at proper temperature, then an aluminum source anda phosphorus source are supplemented to form a crystallized precursor, and crystallization at multiple temperature sections is adopted for synthesizing a MeSAPO-n(n is equal to 5, 11, 17, 18, 34, 35,44, 56) molecular sieve and optimally synthesizing MeSAPO-34. The invention aims to insert metal atoms into the silicoaluminophosphate molecular sieve framework, modulate an acid center property of the silicoaluminophosphate molecular sieve, reduce carbon deposition in reaction for converting an oxygen-containing compound into low carbon olefin, prolong the life of a catalyst, improve the yield ofthe low carbon olefin, and especially increase the yield of ethylene.

The invention provides an iron-manganese-based positive electrode material, and a preparation method and an application thereof. The iron-manganese-based positive electrode material is LiaFexMnyO2, a is equal to 0.1-0.5, x is greater than 0 and less than 1.0, y is greater than 0 and less than 1.0, x + y is equal to 1, the valence state of at least a part of manganese elements in the iron-manganese-based positive electrode material is positive tetravalent, and the maximum intensity of a characteristic peak of a Li2MnO3 crystal phase in an XRD spectrogram of the iron-manganese-based positive electrode material is less than 1 / 3 of the intensity of the strongest characteristic peak of the iron-manganese-based positive electrode material or the characteristic peak of the Li2MnO3 crystal phase does not appear. By controlling the components and the crystal structure of the iron-manganese-based positive electrode material, the first effect and the cycle performance are well improved.

To provide a phosphor given by a general composition formula expressed by MmAaBbOoNn:Z, (wherein element M is one or more kinds of elements having bivalent valency, element A is one or more kinds of elements having tervalent valency, element B is one or more kinds of elements having tetravalent valency, O is oxygen, N is nitrogen, and element Z is one or more kind of activating agent, satisfying m>0, a>0, b>0, o≧0, and n>0), with a change rate of a ratio of element B atoms to the total numbers of atoms being smaller by 10% or the change rate of oxygen atoms to the total numbers of atoms being smaller by 40% in a range from a particle surface up to depth 2000 nm, having a broad emission spectrum in a range of blue color, having a broad flat excitation band in a range of near ultraviolet / ultraviolet, and having excellent emission efficiency, emission intensity, and luminance.

Disclosed is a wavelength conversion member which is a resin-molded article having dispersed therein a complex fluoride fluorophore that absorbs light with a blue wavelength component and emits light including a red wavelength component and that is represented by A2(M1−xMnx)F6 (in the formula: M is at least one type of tetravalent element selected from Si, Ti, Zr, Hf, Ge, and Sn; A is at least one type of alkali metal selected from Li, Na, K, Rb, and Cs and including at least Na and / or K; and x is from 0.001 to 0.3), wherein the hue of the wavelength conversion member when light is not emitted is as follows in CIELAB (CIE 1976): L*=from 40 to 60 inclusive; a*=from 0 to +1 inclusive; and b*=from +2 to +15 inclusive.