Diode end-pumped solid-state lasers have the potential to yield high quality laser beams with high efficiency for laser range finding and warning receiver applications as well as day and night military laser designati...Diode end-pumped solid-state lasers have the potential to yield high quality laser beams with high efficiency for laser range finding and warning receiver applications as well as day and night military laser designation systems. In this paper we presents theoretical calculations using Advanced Dynamics Professional LASCAD software and experimental studies for a high power pigtailed fiber diode laser module of 8 W operating at 808 nm with a specially designed high efficiency cooling system, end pumped high-efficiency Nd:YVO4 laser of 3 × 3 × 10 mm rod and overall cavity length of 44 mm. To the best of our knowledge a self Q-switching effects was generated in Nd:YVO4 laser by changing the cavity dimensions and the position of the intracavity KTP crystal at certain regime of operation for the first time, in which the cavity length is reduced to be 30 mm and the distance between Nd:YVO4 rod and KTP crystal is only 1mm. Self Q-switched laser pulse at 532 nm with high peak power of 96 W, pulse width of 88 ns at FWHM and repetition rate of 400 kHz was achieved. Experimental studies of a passive Q-switched Nd:YVO4 laser using Cr:YAG crystal with three different transmissions of 30%, 40% and 70% were investigated. Passive Q-switched laser pulse at 1064 nm and narrow line width of less than 1.5 nm with highest peak power of nearly 18 kW, short pulse width of less than 4 ns at FWHM and higher repetition rate of 45 kHz using Cr:YAG with transmission of 30% was achieved for the first time.展开更多
The thermal and mechanical properties of Liquid Crystal Elastomers (LCEs) were characterized using various techniques for understanding of their physical behavior. The material used for investigation was synthesized b...The thermal and mechanical properties of Liquid Crystal Elastomers (LCEs) were characterized using various techniques for understanding of their physical behavior. The material used for investigation was synthesized by us, using Finklemann procedure, with proper cross linking density in nematic phase. The material is found to have unique coupling between anisotropicorder of liquid crystal component and elasticity of polymer network. The chemical structures were confirmed by Fourier Transform Infrared (FTIR) Spectroscopy and Scanning Electron Microscopy (SEM). Fabry Perot Scattering Studies (FPSS), Thermo gravimetric Analysis (TGA) and Differential Scanning Calorimatory (DSC) were used to study thermal properties. The mechanical properties were studied using force sensor. Our investigation shows that this synthesized Liquid Crystal Elastomer has ability of spontaneous change as a function of temperature and mechanical force, which shows it as a unique class of soft material.展开更多
A new binuclear copper(Ⅱ) complex, [Cu2(phen)2(H2O)2( μ2-C2O4)](NO3)2, has been synthesized and characterized by elemental analysis, IR and UV-Vis spectrum. Its crystal structure was determined by single crystal X-r...A new binuclear copper(Ⅱ) complex, [Cu2(phen)2(H2O)2( μ2-C2O4)](NO3)2, has been synthesized and characterized by elemental analysis, IR and UV-Vis spectrum. Its crystal structure was determined by single crystal X-ray diffraction techniques. Crystal data: monoclinic, space group P21/c, a=0.712 21(8) nm, b=1.170 93(14) nm, c=1.783 7(2) nm, β=111.828(2)°, and V=1.380 8(3) nm3, Dc=1.769 Mg·m-3, Z=2, F(000)=744, R1=0.025 4, wR2=0.069 5, Gof=1.077, Δρ=328^-455 e·nm-3. The complex is packed by one centrosymmetry binuclear copper(Ⅱ) unit, oxalate dianion and NO3- anion. In the molecule structure of the title complex, two Cu(Ⅱ) ions are bridged by oxalate dianion and each Cu(Ⅱ) ions coordinates with two nitrogen atoms from 1,10-phenanthroline ligand and one oxygen atom from water to form a five-coordinate distorted square-pyramidal configuration. The hydrogen bonds are observed between coordinated water molecules and NO3- anions. The analysis of the crystal structure indicates that the complex has a two-dimensional stacking network structure, which is formed by intramolecular hydrogen bonds, intermolecular hydrogen bonds and stacking effect of aromatic ring. CCDC: 255345.展开更多
A novel coordination polymer of [Ca(2-OPA)2(H2O)2]n (2-OPA-=2-oxo-1(4H)-pyridineacetate anion) was synthesized and characterized by elemental analysis, IR, TG and single crystal X-ray diffraction. The title complex cr...A novel coordination polymer of [Ca(2-OPA)2(H2O)2]n (2-OPA-=2-oxo-1(4H)-pyridineacetate anion) was synthesized and characterized by elemental analysis, IR, TG and single crystal X-ray diffraction. The title complex crystallizes in orthorhombic with space group Pna21, a=0.799 96(16) nm, b=0.823 77(16) nm, c=2.415 3(5) nm, V=1.591 6(6) nm3, Z=4, R=0.030 3, wR=0.070 0. The Ca atom is eight-coordinated by six O atoms of four 2-OPA- ligands and two water molecules, and displays a dodecahedron coordination geometry. Each 2-OPA- ligand bridges two adjacent Ca atoms, forming a infinite chain along the a direction. The Ca...Ca distance is 0.4102 2(8)nm. A two-dimensional supramolecular framework is further constructed by the hydrogen bonds and the weak π-π interactions. The results of TG analysis show the chain structure of the title complex was stable under 297.5 ℃. CCDC: 251669.展开更多
new coordination polymer {[Zn(CF3COO)2(C5H5ON)]·H2O}n was synthesized based on the reaction of zinc(Ⅱ) trifluoroacetate and 3-hydroxypyridine(C5H5ON) in methanol medium for the first time. The structure of the c...new coordination polymer {[Zn(CF3COO)2(C5H5ON)]·H2O}n was synthesized based on the reaction of zinc(Ⅱ) trifluoroacetate and 3-hydroxypyridine(C5H5ON) in methanol medium for the first time. The structure of the coordination polymer was confirmed by IR, 1H NMR, elemental analysis and thermal analysis. The crystal structure of the coordination polymer was also determined by X-ray single crystal diffraction. The crystal belongs to monoclinic system with space group P21/m, and crystallographic data of the coordination polymer are: a= 0.863 1(4) nm, b=0.717 7(3) nm, c=1.116 4(5) nm, α=γ=90°, β=107.542(6)°, V=0.659 4(5) nm3; Dc=2.037 g·cm-3; Z=2; F(000)=400; μ=1.969 mm-1. Zinc(Ⅱ) atom lies at the center of an octahedron formed by the coordination of zinc atom and six O atoms which come from four different trifluoroacetate ions and two different 3-hydroxypyridine molecules where each trifluoroacetate ion and 3-hydroxypyridine are coordinated to two different zinc ions to form coordination polymer. CCDC: 253909.展开更多
A one-dimensional double-chain coordination polymer [Mn(phen)(tsgluo)] was synthesized in a mixed solution and its crystal structure was determined by X-ray diffraction method. It crystallizes in orthorhombic system w...A one-dimensional double-chain coordination polymer [Mn(phen)(tsgluo)] was synthesized in a mixed solution and its crystal structure was determined by X-ray diffraction method. It crystallizes in orthorhombic system with space group P212121. The crystal data are: a=0.530 78(17) nm, b=1.723 9(5) nm, c=2.456 9(8) nm, Z=4, μ=0.729 mm-1, Dc=1.579 g·cm-3, V=2.248 1(12) nm3, R1=0.033 1, ωR2=0.078 9. In the title complex, each Mn(Ⅱ) ion presents a octahedral geometry with the coordination of two nitrogen atoms from 1,10-phenanthroline and four oxygen atoms from three different tsgluo2- ligands. The γ-carboxyl coordinates to Mn(Ⅱ) in the mode of bidentate chelate, while the α-carboxyl coordinates in a bidentate bridging mode. CCDC: 253910.展开更多
Diorganotin(Ⅳ) compound [(p-CNC6H4CH2)2Sn(C9H7N3O3)(H2O)]2 was synthesized by the reaction of tri-p-cyanobenzyltin chloride with Schiff base ligand pyruvic acid isonicotinyl hydrazone. The compound was characterized ...Diorganotin(Ⅳ) compound [(p-CNC6H4CH2)2Sn(C9H7N3O3)(H2O)]2 was synthesized by the reaction of tri-p-cyanobenzyltin chloride with Schiff base ligand pyruvic acid isonicotinyl hydrazone. The compound was characterized by elemental analysis, IR, 1H NMR. The crystal structure was determined by X-ray single crystal diffraction. The crystal belongs to monoclinic space group C2/c, with a=3.143 1(3) nm, b=0.989 99(10) nm, c=1.785 68(18) nm, β=114.908 0(13)°, V=5.039 6(9) nm3, Z=4, μ=1.054 mm-1, Dc=1.513 Mg·m-3, F(000)=2 304, R=0.042 8, wR=0.090 3, GOF=0.997. In this compound, the Sn atom exists in a distorted octahedral coordination environment in which one water molecule, one tridentate pyruvic acid isonicotinyl hydrazone ligand, and two trans p-cyanobenzyl groups coordinate to each Sn center, the angle of the axial C10-Sn1-C18 is 166.1(2)°. Two molecules form a weak-bridged dimmer with weak interactions of Sn...O bonding and hydrogen bonds. CCDC: 270796.展开更多
We present an experimental investigation of a filamentation-assisted fourth-order nonlinear optical process in KTP crystals pumped by intense 1.53 eV （807 nm） femtosecond laser pulses. Femtosecond light pulses at 2....We present an experimental investigation of a filamentation-assisted fourth-order nonlinear optical process in KTP crystals pumped by intense 1.53 eV （807 nm） femtosecond laser pulses. Femtosecond light pulses at 2.58 eV （480 nm） are generated by the fourth-order nonlinear polarization （p（4） （ω2） = X（4） （ω2, ω, ω, ω, -ω1）E3 （ω）E＊ （ω1）, where E（w） corresponds to the pump frequency and E（wl） to the supercontinuum generated through filamentation）. If the system is seeded by a laser beam at ω1 or ω2 and there are spatial and temporal overlaps with the pump beam, E（ω1） and E（ω2） are simultaneously amplified. When the intensity of the seed laser beam exceeds a certain intensity threshold, the contribution of p（4） （ω） = X（4） （ω, ω1, ω2, -ω, -ω）E（ω1）E（ω2）（E＊ （ω））2 becomes non-negligible, and the amplification weakens. The conversion efficiency from the pump to the signal at 2.58 eV （480 nm） attains to 0.1%.展开更多
A novel coordination polymer of [Co( p-CPOA)(2,2′-bipy)(H2O)]n ( p-CPOA2-=4-carboxylphenoxyacetate dianion, 2,2′-bipy=2,2′-bipyridine) was synthesized and characterized by elemental analysis, IR and X-ray single cr...A novel coordination polymer of [Co( p-CPOA)(2,2′-bipy)(H2O)]n ( p-CPOA2-=4-carboxylphenoxyacetate dianion, 2,2′-bipy=2,2′-bipyridine) was synthesized and characterized by elemental analysis, IR and X-ray single crystal diffraction. The title complex crystallizes in monoclinic space group C2/c, with a=1.424 4(3) nm, b=1.316 6(3) nm, c=1.947 7(4) nm, β=104.56(3)°. V=3.535 3(14) nm3, Z=8, R=0.028 5, wR=0.089 1. The cobalt(Ⅱ) ion displays a distorted octahedral coordination geometry, defined by three carboxyl oxygen atoms from different p-CPOA2- groups, two nitrogen atoms from 2,2′-bipyridine ligand and one water molecule. The cobalt atoms are bridged by p-CPOA2- groups, forming a one-dimensional chain structure along a axis. The adjacent Co...Co atoms distance is 0.996 8 nm. A layer supramolecular network is contrsucted by the hydrogen bonds and π-π stacking interactions. CCDC: 220039.展开更多
A large specific surface area perovskite-type mixed oxide PbTiO3 supported cupric oxide was synthesized as a catalyst for NO decomposition and characterized by techniques such as XPS, XRD, H2-TPR before and after NO d...A large specific surface area perovskite-type mixed oxide PbTiO3 supported cupric oxide was synthesized as a catalyst for NO decomposition and characterized by techniques such as XPS, XRD, H2-TPR before and after NO decomposition reactions. The catalytic properties were tested with a fix-bed micro-reactor. The results showed that the PbTiO3 was inactive for the reactions, but 1wt % Cu/PbTiO3 catalyst gave fairly good activities for NO decomposition at temperature as low as 473 K. Copper species were found well-dispersed but weakly interacted with the support before NO decomposition, and the NO decomposition caused significant change in the environment of the copper species, which became Cu(Ⅰ)and most probably incorporated into surface crystal lattice of the nano-sized PbTiO3. In NO reaction, a large amount of oxygen atoms from the decomposition of NO penetrated into the nano-sized PbTiO3 support and caused small expansion of crystal lattice. The transport of oxygen between the copper species and the catalyst support may be helpful to speed up the kinetic regeneration of active metal sites from oxygen occupancy and resulted in good catalytic performance.展开更多
In 2O 3, MgO and Fe 2O 3 were doped in LiNbO3 and Czochralski method was used to grow In:Mg:Fe:LiNbO 3 crystals. The OH - extension transmission spectra, light scattering resistance ability, two wave coupled dif...In 2O 3, MgO and Fe 2O 3 were doped in LiNbO3 and Czochralski method was used to grow In:Mg:Fe:LiNbO 3 crystals. The OH - extension transmission spectra, light scattering resistance ability, two wave coupled diffraction efficiency and response time of the crystal were measured. Codoping In and Mg in crystal will improve its light scattering resistance ability and response time. Doping In can increase the ability to replace antisite Nb and decrease the doping quantity of Mg. All these are propitious to improve the optical homogeneity of crystal. Doping Fe can improve the photorefractive sensitivity for LiNbO 3 crystal. We discussed the site of In, Mg and Fe in LiNbO 3 crystals and the influence of the absorption peak of OH - transmission spectra on photorefractive property for LiNbO 3 crystal.展开更多
In manufacturing process, it is necessary to measure change in CSD (Crystal Size Distribution) with time accurately because CSD is one of the most important indices that evaluate quality of products. FBRM (Focused Bea...In manufacturing process, it is necessary to measure change in CSD (Crystal Size Distribution) with time accurately because CSD is one of the most important indices that evaluate quality of products. FBRM (Focused Beam Reflectance Measurement) can measure CLD (Chord Length Distribution) in line, but CLD is different from CSD because of principle of FBRM. However, if CSD is determined beforehand, CLD can be calculated from the CSD with statistical method. First, when crystal shape is defined from the characteristic crystal size, the matrix of each crystal shape which transforms CSD into CLD in a uniform manner is calculated with Monte Carlo analysis. Characteristic crystal size is added to the variables defining chord length in order to avoid complex integrals and apply the change in crystal shape with characteristic crystal size to the transforming matrix. Secondly, CSD and CLD are actually measured in suspension of acetaminophen in ethanol and suspension of L-arginine in water to demonstrate the validity of 2 matrices. Lastly, these matrices are multiplied by some simple CSD models to test the properties of these matrices and demonstrate the utility of this transformation.展开更多
文摘Diode end-pumped solid-state lasers have the potential to yield high quality laser beams with high efficiency for laser range finding and warning receiver applications as well as day and night military laser designation systems. In this paper we presents theoretical calculations using Advanced Dynamics Professional LASCAD software and experimental studies for a high power pigtailed fiber diode laser module of 8 W operating at 808 nm with a specially designed high efficiency cooling system, end pumped high-efficiency Nd:YVO4 laser of 3 × 3 × 10 mm rod and overall cavity length of 44 mm. To the best of our knowledge a self Q-switching effects was generated in Nd:YVO4 laser by changing the cavity dimensions and the position of the intracavity KTP crystal at certain regime of operation for the first time, in which the cavity length is reduced to be 30 mm and the distance between Nd:YVO4 rod and KTP crystal is only 1mm. Self Q-switched laser pulse at 532 nm with high peak power of 96 W, pulse width of 88 ns at FWHM and repetition rate of 400 kHz was achieved. Experimental studies of a passive Q-switched Nd:YVO4 laser using Cr:YAG crystal with three different transmissions of 30%, 40% and 70% were investigated. Passive Q-switched laser pulse at 1064 nm and narrow line width of less than 1.5 nm with highest peak power of nearly 18 kW, short pulse width of less than 4 ns at FWHM and higher repetition rate of 45 kHz using Cr:YAG with transmission of 30% was achieved for the first time.
文摘The thermal and mechanical properties of Liquid Crystal Elastomers (LCEs) were characterized using various techniques for understanding of their physical behavior. The material used for investigation was synthesized by us, using Finklemann procedure, with proper cross linking density in nematic phase. The material is found to have unique coupling between anisotropicorder of liquid crystal component and elasticity of polymer network. The chemical structures were confirmed by Fourier Transform Infrared (FTIR) Spectroscopy and Scanning Electron Microscopy (SEM). Fabry Perot Scattering Studies (FPSS), Thermo gravimetric Analysis (TGA) and Differential Scanning Calorimatory (DSC) were used to study thermal properties. The mechanical properties were studied using force sensor. Our investigation shows that this synthesized Liquid Crystal Elastomer has ability of spontaneous change as a function of temperature and mechanical force, which shows it as a unique class of soft material.
文摘A new binuclear copper(Ⅱ) complex, [Cu2(phen)2(H2O)2( μ2-C2O4)](NO3)2, has been synthesized and characterized by elemental analysis, IR and UV-Vis spectrum. Its crystal structure was determined by single crystal X-ray diffraction techniques. Crystal data: monoclinic, space group P21/c, a=0.712 21(8) nm, b=1.170 93(14) nm, c=1.783 7(2) nm, β=111.828(2)°, and V=1.380 8(3) nm3, Dc=1.769 Mg·m-3, Z=2, F(000)=744, R1=0.025 4, wR2=0.069 5, Gof=1.077, Δρ=328^-455 e·nm-3. The complex is packed by one centrosymmetry binuclear copper(Ⅱ) unit, oxalate dianion and NO3- anion. In the molecule structure of the title complex, two Cu(Ⅱ) ions are bridged by oxalate dianion and each Cu(Ⅱ) ions coordinates with two nitrogen atoms from 1,10-phenanthroline ligand and one oxygen atom from water to form a five-coordinate distorted square-pyramidal configuration. The hydrogen bonds are observed between coordinated water molecules and NO3- anions. The analysis of the crystal structure indicates that the complex has a two-dimensional stacking network structure, which is formed by intramolecular hydrogen bonds, intermolecular hydrogen bonds and stacking effect of aromatic ring. CCDC: 255345.
文摘A novel coordination polymer of [Ca(2-OPA)2(H2O)2]n (2-OPA-=2-oxo-1(4H)-pyridineacetate anion) was synthesized and characterized by elemental analysis, IR, TG and single crystal X-ray diffraction. The title complex crystallizes in orthorhombic with space group Pna21, a=0.799 96(16) nm, b=0.823 77(16) nm, c=2.415 3(5) nm, V=1.591 6(6) nm3, Z=4, R=0.030 3, wR=0.070 0. The Ca atom is eight-coordinated by six O atoms of four 2-OPA- ligands and two water molecules, and displays a dodecahedron coordination geometry. Each 2-OPA- ligand bridges two adjacent Ca atoms, forming a infinite chain along the a direction. The Ca...Ca distance is 0.4102 2(8)nm. A two-dimensional supramolecular framework is further constructed by the hydrogen bonds and the weak π-π interactions. The results of TG analysis show the chain structure of the title complex was stable under 297.5 ℃. CCDC: 251669.
文摘new coordination polymer {[Zn(CF3COO)2(C5H5ON)]·H2O}n was synthesized based on the reaction of zinc(Ⅱ) trifluoroacetate and 3-hydroxypyridine(C5H5ON) in methanol medium for the first time. The structure of the coordination polymer was confirmed by IR, 1H NMR, elemental analysis and thermal analysis. The crystal structure of the coordination polymer was also determined by X-ray single crystal diffraction. The crystal belongs to monoclinic system with space group P21/m, and crystallographic data of the coordination polymer are: a= 0.863 1(4) nm, b=0.717 7(3) nm, c=1.116 4(5) nm, α=γ=90°, β=107.542(6)°, V=0.659 4(5) nm3; Dc=2.037 g·cm-3; Z=2; F(000)=400; μ=1.969 mm-1. Zinc(Ⅱ) atom lies at the center of an octahedron formed by the coordination of zinc atom and six O atoms which come from four different trifluoroacetate ions and two different 3-hydroxypyridine molecules where each trifluoroacetate ion and 3-hydroxypyridine are coordinated to two different zinc ions to form coordination polymer. CCDC: 253909.
文摘A one-dimensional double-chain coordination polymer [Mn(phen)(tsgluo)] was synthesized in a mixed solution and its crystal structure was determined by X-ray diffraction method. It crystallizes in orthorhombic system with space group P212121. The crystal data are: a=0.530 78(17) nm, b=1.723 9(5) nm, c=2.456 9(8) nm, Z=4, μ=0.729 mm-1, Dc=1.579 g·cm-3, V=2.248 1(12) nm3, R1=0.033 1, ωR2=0.078 9. In the title complex, each Mn(Ⅱ) ion presents a octahedral geometry with the coordination of two nitrogen atoms from 1,10-phenanthroline and four oxygen atoms from three different tsgluo2- ligands. The γ-carboxyl coordinates to Mn(Ⅱ) in the mode of bidentate chelate, while the α-carboxyl coordinates in a bidentate bridging mode. CCDC: 253910.
文摘Diorganotin(Ⅳ) compound [(p-CNC6H4CH2)2Sn(C9H7N3O3)(H2O)]2 was synthesized by the reaction of tri-p-cyanobenzyltin chloride with Schiff base ligand pyruvic acid isonicotinyl hydrazone. The compound was characterized by elemental analysis, IR, 1H NMR. The crystal structure was determined by X-ray single crystal diffraction. The crystal belongs to monoclinic space group C2/c, with a=3.143 1(3) nm, b=0.989 99(10) nm, c=1.785 68(18) nm, β=114.908 0(13)°, V=5.039 6(9) nm3, Z=4, μ=1.054 mm-1, Dc=1.513 Mg·m-3, F(000)=2 304, R=0.042 8, wR=0.090 3, GOF=0.997. In this compound, the Sn atom exists in a distorted octahedral coordination environment in which one water molecule, one tridentate pyruvic acid isonicotinyl hydrazone ligand, and two trans p-cyanobenzyl groups coordinate to each Sn center, the angle of the axial C10-Sn1-C18 is 166.1(2)°. Two molecules form a weak-bridged dimmer with weak interactions of Sn...O bonding and hydrogen bonds. CCDC: 270796.
基金Project supported by the National Basic Research Program,China (Grant No. 2006CB806007)the National Natural Science Foundation of China (Grant Nos. 10574006,10634020 and 10821062)
文摘We present an experimental investigation of a filamentation-assisted fourth-order nonlinear optical process in KTP crystals pumped by intense 1.53 eV （807 nm） femtosecond laser pulses. Femtosecond light pulses at 2.58 eV （480 nm） are generated by the fourth-order nonlinear polarization （p（4） （ω2） = X（4） （ω2, ω, ω, ω, -ω1）E3 （ω）E＊ （ω1）, where E（w） corresponds to the pump frequency and E（wl） to the supercontinuum generated through filamentation）. If the system is seeded by a laser beam at ω1 or ω2 and there are spatial and temporal overlaps with the pump beam, E（ω1） and E（ω2） are simultaneously amplified. When the intensity of the seed laser beam exceeds a certain intensity threshold, the contribution of p（4） （ω） = X（4） （ω, ω1, ω2, -ω, -ω）E（ω1）E（ω2）（E＊ （ω））2 becomes non-negligible, and the amplification weakens. The conversion efficiency from the pump to the signal at 2.58 eV （480 nm） attains to 0.1%.
文摘A novel coordination polymer of [Co( p-CPOA)(2,2′-bipy)(H2O)]n ( p-CPOA2-=4-carboxylphenoxyacetate dianion, 2,2′-bipy=2,2′-bipyridine) was synthesized and characterized by elemental analysis, IR and X-ray single crystal diffraction. The title complex crystallizes in monoclinic space group C2/c, with a=1.424 4(3) nm, b=1.316 6(3) nm, c=1.947 7(4) nm, β=104.56(3)°. V=3.535 3(14) nm3, Z=8, R=0.028 5, wR=0.089 1. The cobalt(Ⅱ) ion displays a distorted octahedral coordination geometry, defined by three carboxyl oxygen atoms from different p-CPOA2- groups, two nitrogen atoms from 2,2′-bipyridine ligand and one water molecule. The cobalt atoms are bridged by p-CPOA2- groups, forming a one-dimensional chain structure along a axis. The adjacent Co...Co atoms distance is 0.996 8 nm. A layer supramolecular network is contrsucted by the hydrogen bonds and π-π stacking interactions. CCDC: 220039.
文摘A large specific surface area perovskite-type mixed oxide PbTiO3 supported cupric oxide was synthesized as a catalyst for NO decomposition and characterized by techniques such as XPS, XRD, H2-TPR before and after NO decomposition reactions. The catalytic properties were tested with a fix-bed micro-reactor. The results showed that the PbTiO3 was inactive for the reactions, but 1wt % Cu/PbTiO3 catalyst gave fairly good activities for NO decomposition at temperature as low as 473 K. Copper species were found well-dispersed but weakly interacted with the support before NO decomposition, and the NO decomposition caused significant change in the environment of the copper species, which became Cu(Ⅰ)and most probably incorporated into surface crystal lattice of the nano-sized PbTiO3. In NO reaction, a large amount of oxygen atoms from the decomposition of NO penetrated into the nano-sized PbTiO3 support and caused small expansion of crystal lattice. The transport of oxygen between the copper species and the catalyst support may be helpful to speed up the kinetic regeneration of active metal sites from oxygen occupancy and resulted in good catalytic performance.
文摘In 2O 3, MgO and Fe 2O 3 were doped in LiNbO3 and Czochralski method was used to grow In:Mg:Fe:LiNbO 3 crystals. The OH - extension transmission spectra, light scattering resistance ability, two wave coupled diffraction efficiency and response time of the crystal were measured. Codoping In and Mg in crystal will improve its light scattering resistance ability and response time. Doping In can increase the ability to replace antisite Nb and decrease the doping quantity of Mg. All these are propitious to improve the optical homogeneity of crystal. Doping Fe can improve the photorefractive sensitivity for LiNbO 3 crystal. We discussed the site of In, Mg and Fe in LiNbO 3 crystals and the influence of the absorption peak of OH - transmission spectra on photorefractive property for LiNbO 3 crystal.
文摘In manufacturing process, it is necessary to measure change in CSD (Crystal Size Distribution) with time accurately because CSD is one of the most important indices that evaluate quality of products. FBRM (Focused Beam Reflectance Measurement) can measure CLD (Chord Length Distribution) in line, but CLD is different from CSD because of principle of FBRM. However, if CSD is determined beforehand, CLD can be calculated from the CSD with statistical method. First, when crystal shape is defined from the characteristic crystal size, the matrix of each crystal shape which transforms CSD into CLD in a uniform manner is calculated with Monte Carlo analysis. Characteristic crystal size is added to the variables defining chord length in order to avoid complex integrals and apply the change in crystal shape with characteristic crystal size to the transforming matrix. Secondly, CSD and CLD are actually measured in suspension of acetaminophen in ethanol and suspension of L-arginine in water to demonstrate the validity of 2 matrices. Lastly, these matrices are multiplied by some simple CSD models to test the properties of these matrices and demonstrate the utility of this transformation.
