Due to their high electrical conductivity and layered structure,two dimensional MXene materials are re⁃garded as promising candidates for energy storage applications.However,the relatively low stability and specific c...Due to their high electrical conductivity and layered structure,two dimensional MXene materials are re⁃garded as promising candidates for energy storage applications.However,the relatively low stability and specific ca⁃pacity of MXene materials limit their further utilization.In this study,these issues are addressed using a heterostruc⁃ture strategy via a one-step selenization method to form Mo_(2)C@MoSe_(2).Synchrotron radiation X-ray spectroscopic and high-resolution transmission electron microscopy(HRTEM)characterizations revealed the heterostructure consisting of in-situ grown MoSe_(2)on Mo_(2)C MXene.Electrochemical tests proved the heterojunction electrode’s superior rate perfor⁃mance of 289.06 mAh·g^(-1)at a high current density of 5 A·g^(-1)and long cycling stability of 550 mAh·g^(-1)after 900 cycles at 1 A·g^(-1).This work highlights the useful X-ray spectroscopic analysis to directly elucidate the heterojunction structure,providing an effective reference method for probing heterostructures.展开更多
We report on using synthetic silicon for a high-precision X-ray polarimeter comprising a polarizer and an analyzer,each based on a monolithic channel-cut crystal used at multiple Brewster reflections with a Bragg angl...We report on using synthetic silicon for a high-precision X-ray polarimeter comprising a polarizer and an analyzer,each based on a monolithic channel-cut crystal used at multiple Brewster reflections with a Bragg angle very close to 45°.Experiments were performed at the BL09B bending magnet beamline of the Shanghai Synchrotron Radiation Facility using a Si(800)crystal at an X-ray energy of 12.914 keV.A polarization purity of 8.4×10^(-9)was measured.This result is encouraging,as the measured polarization purity is the best-reported value for the bending magnet source.Notably,this is the firstly systematic study on the hard X-ray polarimeter in China,which is crucial for exploring new physics,such as verifying vacuum birefringence.展开更多
Monochromatic x-ray imaging is an essential method for plasma diagnostics related to density information.Large-field high-resolution monochromatic imaging of a He-like iron(Fe XXV)Kαcharacteristic line(6.701 keV)for ...Monochromatic x-ray imaging is an essential method for plasma diagnostics related to density information.Large-field high-resolution monochromatic imaging of a He-like iron(Fe XXV)Kαcharacteristic line(6.701 keV)for laser plasma diagnostics was achieved using a developed toroidal crystal x-ray imager.A high-index crystal orientation Ge(531)wafer with a Bragg angle of 75.37°and the toroidal substrate were selected to obtain sufficient diffraction efficiency and compensate for astigmatism under oblique incidence.A precise offline assembly method of the toroidal crystal imager based on energy substitution was proposed,and a spatial resolution of 3-7μm was obtained by toroidal crystal imaging of a 600 line-pairs/inch Au grid within an object field of view larger than 1.0 mm.The toroidal crystal x-ray imager has been successfully tested via side-on backlight imaging experiments of the sinusoidal modulation target and a 1000 line-pairs/inch Au grid with a linewidth of 5μm using an online alignment method based on dual positioning balls to indicate the target and backlighter.This paper describes the optical design,adjustment method,and experimental results of a toroidal crystal system in a laboratory and laser facility.展开更多
Low-dimensional halide perovskites have become the most promising candidates for X-ray imaging,yet the issues of the poor chemical stability of hybrid halide perovskite,the high poisonousness of lead halides and the r...Low-dimensional halide perovskites have become the most promising candidates for X-ray imaging,yet the issues of the poor chemical stability of hybrid halide perovskite,the high poisonousness of lead halides and the relatively low detectivity of the lead-free halide perovskites which seriously restrain its commercialization.Here,we developed a solution inverse temperature crystal growth(ITCG)method to bring-up high quality Cs_(3)Cu_(2)I_(5)crystals with large size of centimeter order,in which the oleic acid(OA)is introduced as an antioxidative ligand to inhibit the oxidation of cuprous ions effieiently,as well as to decelerate the crystallization rate remarkalby.Based on these fine crystals,the vapor deposition technique is empolyed to prepare high quality Cs_(3)Cu_(2)I_(5)films for efficient X-ray imaging.Smooth surface morphology,high light yields and short decay time endow the Cs_(3)Cu_(2)I_(5)films with strong radioluminescence,high resolution(12 lp/mm),low detection limits(53 nGyair/s)and desirable stability.Subsequently,the Cs_(3)Cu_(2)I_(5)films have been applied to the practical radiography which exhibit superior X-ray imaging performance.Our work provides a paradigm to fabricate nonpoisonous and chemically stable inorganic halide perovskite for X-ray imaging.展开更多
Spectroscopic properties of Ce-doped yttrium orthoaluminate (Ce:YA1O3 or Ce:YAP) crystals gown by temperature gradient technique (TGT) were investigated, and the effects of the growth conditions on the propertie...Spectroscopic properties of Ce-doped yttrium orthoaluminate (Ce:YA1O3 or Ce:YAP) crystals gown by temperature gradient technique (TGT) were investigated, and the effects of the growth conditions on the properties were analyzed. Methods of optical absorption (OA), photoluminescence (PL), photoluminescence decay (PLD), X-my excited luminescence (XL) and cathodeluminescence (CL) were used in these investigations. The results showed that the absorption band peak at 202,394 and 532 nm originated from F and F^+ color center induced by the weak reducing growth atmosphere, green emission band near 500 nm derived from Ce3^+ -Ce^3+ pairs and band at 650 - 850 nm from some unintentional impurity in crystals.展开更多
The Yb3+:LiGd(WO4)2 crystal with the dimension of Ф15×35 mm3 was grown by Czochralski technique. The spectroscopic characterization and fluorescence dynamics of Yb3+ in yb3+:LiGd(WO4)2 crystal were inve...The Yb3+:LiGd(WO4)2 crystal with the dimension of Ф15×35 mm3 was grown by Czochralski technique. The spectroscopic characterization and fluorescence dynamics of Yb3+ in yb3+:LiGd(WO4)2 crystal were investigated. The yb3+:LiGd(WO4)2 crystal exhibits a broad absorption band centered near 975 nm with the linewidths of 16 and 11 nm and maximal absorption cross-section of 3.60 × 10-20 and 2.90× 10-20 cm2 for π- and σ-polarization, respectively. The emission broadband has an FWHM of 47 and 45 nm with the emission cross sections of 3.92 × 10-20 and 3.34× 10-2o cm2 at 1020 nm for re- and or-polarization, respectively. The measured fluorescence lifetime is 398 gs. The blue light emission around 480 nm through cooperative upconversion from the de-excitation of excited Yb3+-Yb3+ pairs at 4 K was observed under 932-nm excitation and demonstrated.展开更多
Inversion techniques are conducted based on the tangential x-ray crystal spectroscopy(TXCS)geometry on EAST to obtain the local profiles of ion temperature(Ti)and toroidal rotation velocity(vt).Firstly,local emissivit...Inversion techniques are conducted based on the tangential x-ray crystal spectroscopy(TXCS)geometry on EAST to obtain the local profiles of ion temperature(Ti)and toroidal rotation velocity(vt).Firstly,local emissivity profiles of the impurity argon are obtained using the asymmetrical Abel inversion.Then,the local vt and Ti profiles are calculated by considering the local emissivity profiles and the TXCS detailed geometry.In addition,how the changes in the vt profiles affect the accuracy in the Ti profiles is discussed in detail.It is also found that the lineintegrated Ti profiles are becoming less accurate with the increase in the radial gradient in the local vt profiles.Nonetheless,accurate Ti radial profiles are reconstructed after considering the effects of the emissivity and velocity,which are verified by comparing the inverted vt and Ti profiles with those local profile measurements from the Charge eXchange Recombination Spectroscopy(CXRS)on EAST.展开更多
Nd3+: Li3Ba2La3(MoO4)8 crystal has been grown from a flux of Li2MoO4 by the top seeded solution growth method (TSSG) and its structure was confirmed by X-ray diffraction. The polarized absorption spectra, fluore...Nd3+: Li3Ba2La3(MoO4)8 crystal has been grown from a flux of Li2MoO4 by the top seeded solution growth method (TSSG) and its structure was confirmed by X-ray diffraction. The polarized absorption spectra, fluorescence spectra and fluorescence decay curve of the crystal were measured. The main spectral parameters were calculated by the Judd-Ofelt theory and compared with other Nd-doped crystals. The broad absorption bands and the large absorption cross sections around 805 nm indicate that the crystal is very suitable for diode-laser pumping. The broad emission bands around 1060 nm show that the crystal is a potential medium for tunable and short pulse lasers. The quantum efficiency of the crystal is up to 95%, which is higher than the value for Nd3+:YVO4 and Nd3+:YAG and comparable to that of other disordered molybdate crystals. The excellent spectroscopic properties show that Nd3+:Li3Ba2La3(MoO4)8 crystal may be regarded as a potential solid state laser host material for diode laser pumping.展开更多
Tricyanide building block K[Ru(ttpy)(CN)3] and [MnⅢ(salen)](ClO4) have been used to design and synthesize a heterobimetallic one-dimensional(1D) zigzag chain complex 1,[RuⅡ(ttpy)(CN)3 MnⅢ(salen)](ttpy = 4′-(p-toly...Tricyanide building block K[Ru(ttpy)(CN)3] and [MnⅢ(salen)](ClO4) have been used to design and synthesize a heterobimetallic one-dimensional(1D) zigzag chain complex 1,[RuⅡ(ttpy)(CN)3 MnⅢ(salen)](ttpy = 4′-(p-tolyl)-2,2′:6′,2″-terpyridine, salen = N,N?-ethylenebis-(salicylideneaminato)dianion). Single-crystal X-ray diffraction analysis shows complex 1 crystallizes in orthorhombic Pbca space group and the asymmetric unit of 1 contains one[-NC-RuⅡ(ttpy)(CN)(m-CN)-Mn Ⅲ-(salen)-] molecule. In the structure of 1, each [Ru Ⅱ(ttpy)(CN)3]-connects two [MnⅢ(salen)]+ with two cyanide groups in a cis-conformation, and in turn each[MnⅢ(salen)]+ unit links two [RuⅡ(ttpy)(CN)3]-building blocks in a trans-conformation, resulting in a 1D [-NC-RuⅡ-CN-MnⅢ-]n chain. Furthermore, the electronic absorption spectra and luminescence spectroscopy of complex 1 have also been studied.展开更多
Laser-driven proton-induced x-ray emission(laser-PIXE) is a nuclear analysis method based on the compact laser ion accelerator. Due to the transient process of ion acceleration, the laser-PIXE signals are usually spur...Laser-driven proton-induced x-ray emission(laser-PIXE) is a nuclear analysis method based on the compact laser ion accelerator. Due to the transient process of ion acceleration, the laser-PIXE signals are usually spurted within nanoseconds and accompanied by strong electromagnetic pulses(EMP), so traditional multi-channel detectors are no longer applicable.In this work, we designed a reflective elliptical crystal spectrometer for the diagnosis of laser-PIXE. The device can detect the energy range of 1 keV–11 ke V with a high resolution. A calibration experiment was completed on the electrostatic accelerator of Peking University using samples of Al, Ti, Cu, and ceramic artifacts. The detection efficiency of the elliptical crystal spectrometer was obtained in the order of 10-9.展开更多
This paper reports the growth, X-ray diffraction and spectroscopy of Nd3+:Sr3Gd2(BO3)4 crystal. A Nd3+:Sr3Gd2(BO3)4 crystal with dimensions of φ20 × 45 mm3 has been grown by the Czochralski method. Nd3+...This paper reports the growth, X-ray diffraction and spectroscopy of Nd3+:Sr3Gd2(BO3)4 crystal. A Nd3+:Sr3Gd2(BO3)4 crystal with dimensions of φ20 × 45 mm3 has been grown by the Czochralski method. Nd3+:Sr3Gd2(BO3)4 crystal belongs to the orthorhombic system, space group Pnma (D2h) with a = 0.7401, b = 1.604 and c = 0.8755 nm. The absorption and emission spectra of Nd3+:Sr3Gd2(BO3)4 were investigated. The absorption cross section oa is 3.11 × 10^-20cm2 at 808 nm. The absorption transition at 808 nm has an FWHM of 14 nm. The luminescence lifetime τf is 51.7 μs. The emission cross section oc at 1064 nm wavelength is 1.09 × 10^-19 cm2.展开更多
Semiconductor materials exemplify humanity's unwavering pursuit of enhanced performance,efficiency,and functionality in electronic devices.From its early iterations to the advanced variants of today,this field has...Semiconductor materials exemplify humanity's unwavering pursuit of enhanced performance,efficiency,and functionality in electronic devices.From its early iterations to the advanced variants of today,this field has undergone an extraordinary evolution.As the reliability requirements of integrated circuits continue to increase,the industry is placing greater emphasis on the crystal qualities.Consequently,conducting a range of characterization tests on the crystals has become necessary.This paper will examine the correlation between crystal quality,device performance,and production yield,emphasizing the significance of crystal characterization tests and the important role of high-precision synchrotron radiation X-ray topography characterization in semiconductor analysis.Finally,we will cover the specific applications of synchrotron radiation characterization in the development of semiconductor materials.展开更多
A fluorinated tetraphenylbenzidine derivative, N,N′-diphenyl-N,N′-bis(2-fluorophenyl)-1,1′-biphenyl-4,4′-diamine (C36H26F2N2, Mr = 524.59) was synthesized via the palladiumcatalyzed Buchwald-Hartwig reaction o...A fluorinated tetraphenylbenzidine derivative, N,N′-diphenyl-N,N′-bis(2-fluorophenyl)-1,1′-biphenyl-4,4′-diamine (C36H26F2N2, Mr = 524.59) was synthesized via the palladiumcatalyzed Buchwald-Hartwig reaction of N,N′-diphenyl-1,1′-biphenyl-4,4′-diamine with 2-fluoroiodobenzene (yield: 75%) and structurally characterized. It crystallizes in monoclinic, space group P21/n with a = 9.820(7), b = 14.305(11), c = 10.233(8) , β = 108.973(9)o, V = 1359.3(18) 3, Z = 2, Dc = 1.282 g/cm3, μ(MoKα) = 0.084 mm-1, F(000) = 548, S = 1.018, the final R = 0.0439 and wR = 0.0928. It presents a linear centrosymmetric framework constituted by a linkage of biphenyl as a bridge and two fluorinated diphenylamine moieties. The UV-Vis absorption and fluorescence spectra of the title compound were also investigated. This compound emits intense blue fluorescence with a peak wavelength of 406 nm in film.展开更多
A novel palladium(II) complex [(TMEDA)Pd(anca)2].2DMSO (1, TMEDA = N,N,N',N'-tetramethylethylethylenediamine, anca = anthracene-9-carboxylic acid) was synthesized and characterized by single-crystal X-ray di...A novel palladium(II) complex [(TMEDA)Pd(anca)2].2DMSO (1, TMEDA = N,N,N',N'-tetramethylethylethylenediamine, anca = anthracene-9-carboxylic acid) was synthesized and characterized by single-crystal X-ray diffraction, 1H NMR, UV-Vis and fluorescence spectroscopy. The cell belongs to orthorhombic Aba2 space group with a = 19.698(7), b = 21.045(7) c = 9.062(3) A, Z = 4, V= 3757(2) A3, C40H46N206PdS2, Mr = 821.31, D, = 1.452 g/cm3, F(000) = 1704, the final R = 0.0272, wR = 0.0667 and GOOF = 0.999. Complex 1 exhibits an interesting distorted clip-shaped molecular configuration which is stabilized by intramolecular C-H...O hydrogen bonds. The cells are packed into a 3D supramolecular structure based on the intermolecular C-H...zr interactions which further construct the tubular channels serving as guest molecular channels to include the DMSO solvent molecules inside. Furthermore, the spectroscopic properties of 1 were also investigated.展开更多
Two novel mono-nuclear zinc(Ⅱ) complexes with oligoaniline-functionalized terpyridine ligands have been synthesized and verified by 1H-NMR,13C-NMR,Elemental Analysis (EA) and X-ray Diffraction (XRD). The UV-vis...Two novel mono-nuclear zinc(Ⅱ) complexes with oligoaniline-functionalized terpyridine ligands have been synthesized and verified by 1H-NMR,13C-NMR,Elemental Analysis (EA) and X-ray Diffraction (XRD). The UV-vis spectra show the ligand-centered (LC) π-π* transitions and intra-ligand charge transfer (1ILCT) transitions,and the 1ILCT band red-shifts with the increasing number of aromatic amine groups in the ligands. Complex [Zn(L1)2](PF6)2 with an aromatic amine group in ligand shows a strong emission peak at 523 nm in the MeCN solution at 293 K and a blue-shifted band at 517 nm in the alcoholic glass at 77 K. However,for complex [Zn(L2)2](PF6)2 containing aniline dimer modified ligand,no apparent emission can be observed in the MeCN solution at room temperature due to a PET non-radiative decay pathway. Both of them show multiplicate redox processes based on oligoaniline and terpyridine units. The shifts of redox potentials also reflect the D-A interactions between the oligoaniline units and [Zn(TPY)2]2+ core.展开更多
The compound 3,3'-(anthracene-9,10-diyl)bis(1-phenylpropan-1-one)(C32H26O2,Mr=442.55) has been synthesized by the reaction of 2,2'-(anthracene-9,10-diylbis(methy-lene))bis(1,3-diphenylpropane-1,3-dione) ...The compound 3,3'-(anthracene-9,10-diyl)bis(1-phenylpropan-1-one)(C32H26O2,Mr=442.55) has been synthesized by the reaction of 2,2'-(anthracene-9,10-diylbis(methy-lene))bis(1,3-diphenylpropane-1,3-dione) with CsCO3,and its structure was characterized by 1H NMR and single-crystal X-ray diffraction.The crystal of the title compound belongs to monoclinic,space group P21/c with a=9.154(3),b=5.2777(16),c=24.897(7) nm,β=107.337(10)°,Z=2 and V=1.1482 nm3.X-ray analysis indicates that an intermolecular hydrogen bond C(8)-H(8A)…O(1),weak C-H···π between H(9A) and the centre of anthracene rings and weak π-π interactions between two anthracene ring planes are observed.展开更多
New metal complexes of N-benzyl-N-nitrosohy-droxylamine (BNHA) are isolated and characterized by elemental analysis, IR and UV-VIS spectroscopy. Spectrophotometric titration of aqueous solutions of BNHА by salts of s...New metal complexes of N-benzyl-N-nitrosohy-droxylamine (BNHA) are isolated and characterized by elemental analysis, IR and UV-VIS spectroscopy. Spectrophotometric titration of aqueous solutions of BNHА by salts of some transition metals allowed to calculate the composition and formation constants of the metal complexes. The crystal structure of Cu (BNHА)2 is studied by X-ray diffraction. The Cu atom is coordinated by four O atoms of two bidentate ligands, which close 5-membered chelate rings. The N-O (1.306 ? - 1.320 ?) and N-N (1.274?? and 1.275? ) bond lengths indicate that π electrons are delocalized over the chelating groups. Complexes form stacks with intermolecular Cu…N contacts equal to 3.118?? and 3.306 ?.展开更多
Th(BrO3)3·H2O single crystals were grown from its aqueous solution at room temperature. Single crystal XRD, Raman and FTIR techniques were used to investigate the crystal structure. The crystal structure was solv...Th(BrO3)3·H2O single crystals were grown from its aqueous solution at room temperature. Single crystal XRD, Raman and FTIR techniques were used to investigate the crystal structure. The crystal structure was solved by Patterson method. The as grown crystals are in monoclinic system with space group P21/c. The unit cell parameters are a = 12.8555(18) ?, b = 7.8970(11) ?, c = 9.0716(10)?, α = 90°, β = 131.568° and γ = 90° and unit cell volume is 689.1(2)?3. Z = 8, R factor is 5.9. The Raman and FTIR studies indicate the lowering of symetry of bromate anion from C3V to C1. Hydrogen bonds with varying strengths are present in the crystal. The centrosymmetric space group P21/c of the crystal is confirmed by the non-coincidence of majority of Raman and IR bands.展开更多
A novel and simple synthetic way using NaBH4 in the mixure of H2O-THF was applied to prepare 1,2-bis(diphenylphosphinoborane)ethane, dppe(BH3)2, in high yield and purity. The phosphanylborohydride compound dppe(BH3)2 ...A novel and simple synthetic way using NaBH4 in the mixure of H2O-THF was applied to prepare 1,2-bis(diphenylphosphinoborane)ethane, dppe(BH3)2, in high yield and purity. The phosphanylborohydride compound dppe(BH3)2 was isolated in the form of colorless crystals and characterized by single crystal X-ray diffraction, 1H, 13C, 31P and 11B NMR spectroscopy. Prismatic colorless crystals of dppe(BH3)2 were obtained in monoclinic crystal system and space group P21 with two asymmetric units in the unit cell. Lattice parameters were: a = 11.657(2), b = 17.237(2), c = 12.764(2) ?, β = 98.735(14)°, 2535.0(7) ?展开更多
New transition metal complex of Cobalt(III) of the ligand (E)-3-(1-(2-aminoethylimino)ethyl)-4-hydroxy-2H-chromen-2-one, derived from condensation of ethylene diamine with 3-acetyl-4-hydroxy-chromene-2-one have been s...New transition metal complex of Cobalt(III) of the ligand (E)-3-(1-(2-aminoethylimino)ethyl)-4-hydroxy-2H-chromen-2-one, derived from condensation of ethylene diamine with 3-acetyl-4-hydroxy-chromene-2-one have been synthesized by reaction of cobalt(III) salt and the ligand, in amounts equal to metal-ligand molar ratio of 1:2. Both the Schiff base and the complex of Co(III) were characterized by IR, UV-Vis, 1H NMR- and 13C NMR-spectroscopy techniques. Single crystal X-ray diffraction investigation, at low temperature T = 120 K, shows that the cobalt complex is triclinic P-1, a = 10.426(5) ?, b = 11.3234(2) ?, c = 15.729(5) ?, α(°) = 70.102(4), β(°) = 86.049(4), γ(°) = 82.497(4), Z = 2, and its structure consists of isolated [Co(III)(C13H13N2O3)2]+ complex cations with distorted octahedral geometry, ClO-4 counter anions, acetone solvent and water molecules. The crystal cohesion is stabilized by hydrogen bonds between ligands and water molecules, and ionic interactions between complex cations and counter anions.展开更多
基金National Key Research and Development Program of China(2020YFA0405800)National Natural Science Foundation of China(12322515,U23A20121,12225508)+2 种基金Youth Innovation Promotion Association of CAS(2022457)National Postdoctoral Program for Innovative Talents(BX20230346)China Postdoctoral Science Foundation(2023M743365)。
文摘Due to their high electrical conductivity and layered structure,two dimensional MXene materials are re⁃garded as promising candidates for energy storage applications.However,the relatively low stability and specific ca⁃pacity of MXene materials limit their further utilization.In this study,these issues are addressed using a heterostruc⁃ture strategy via a one-step selenization method to form Mo_(2)C@MoSe_(2).Synchrotron radiation X-ray spectroscopic and high-resolution transmission electron microscopy(HRTEM)characterizations revealed the heterostructure consisting of in-situ grown MoSe_(2)on Mo_(2)C MXene.Electrochemical tests proved the heterojunction electrode’s superior rate perfor⁃mance of 289.06 mAh·g^(-1)at a high current density of 5 A·g^(-1)and long cycling stability of 550 mAh·g^(-1)after 900 cycles at 1 A·g^(-1).This work highlights the useful X-ray spectroscopic analysis to directly elucidate the heterojunction structure,providing an effective reference method for probing heterostructures.
基金supported by the Shanghai Municipal Science and Technology Major Project(No.2017SHZDZX02)the National Natural Science Foundation of China(No.12205360)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(No.2018297)。
文摘We report on using synthetic silicon for a high-precision X-ray polarimeter comprising a polarizer and an analyzer,each based on a monolithic channel-cut crystal used at multiple Brewster reflections with a Bragg angle very close to 45°.Experiments were performed at the BL09B bending magnet beamline of the Shanghai Synchrotron Radiation Facility using a Si(800)crystal at an X-ray energy of 12.914 keV.A polarization purity of 8.4×10^(-9)was measured.This result is encouraging,as the measured polarization purity is the best-reported value for the bending magnet source.Notably,this is the firstly systematic study on the hard X-ray polarimeter in China,which is crucial for exploring new physics,such as verifying vacuum birefringence.
基金National Natural Science Foundation of China(No.11805212)National Key Research and Development Program of China(No.2019YFE03080200)。
文摘Monochromatic x-ray imaging is an essential method for plasma diagnostics related to density information.Large-field high-resolution monochromatic imaging of a He-like iron(Fe XXV)Kαcharacteristic line(6.701 keV)for laser plasma diagnostics was achieved using a developed toroidal crystal x-ray imager.A high-index crystal orientation Ge(531)wafer with a Bragg angle of 75.37°and the toroidal substrate were selected to obtain sufficient diffraction efficiency and compensate for astigmatism under oblique incidence.A precise offline assembly method of the toroidal crystal imager based on energy substitution was proposed,and a spatial resolution of 3-7μm was obtained by toroidal crystal imaging of a 600 line-pairs/inch Au grid within an object field of view larger than 1.0 mm.The toroidal crystal x-ray imager has been successfully tested via side-on backlight imaging experiments of the sinusoidal modulation target and a 1000 line-pairs/inch Au grid with a linewidth of 5μm using an online alignment method based on dual positioning balls to indicate the target and backlighter.This paper describes the optical design,adjustment method,and experimental results of a toroidal crystal system in a laboratory and laser facility.
基金the financially support of the National Natural Science Foundation of China(12164051)the Joint Foundation of Provincial Science and Technology Department-Double First-class Construction of Yunnan University(2019FY003016)+4 种基金the Young Top Talent Project of Yunnan Province(YNWR-QNBJ-2018-229)the financially support by Yunnan Major Scientific and Technological Projects(202202AG050016)Advanced Analysis and Measurement Center of Yunnan University for the sample characterization service and the Postgraduate Research and Innovation Foundation of Yunnan University(2021Y036)the financially support of the National Natural Science Foundation of China(62064013)the Application Basic Research Project of Yunnan Province[2019FB130]。
文摘Low-dimensional halide perovskites have become the most promising candidates for X-ray imaging,yet the issues of the poor chemical stability of hybrid halide perovskite,the high poisonousness of lead halides and the relatively low detectivity of the lead-free halide perovskites which seriously restrain its commercialization.Here,we developed a solution inverse temperature crystal growth(ITCG)method to bring-up high quality Cs_(3)Cu_(2)I_(5)crystals with large size of centimeter order,in which the oleic acid(OA)is introduced as an antioxidative ligand to inhibit the oxidation of cuprous ions effieiently,as well as to decelerate the crystallization rate remarkalby.Based on these fine crystals,the vapor deposition technique is empolyed to prepare high quality Cs_(3)Cu_(2)I_(5)films for efficient X-ray imaging.Smooth surface morphology,high light yields and short decay time endow the Cs_(3)Cu_(2)I_(5)films with strong radioluminescence,high resolution(12 lp/mm),low detection limits(53 nGyair/s)and desirable stability.Subsequently,the Cs_(3)Cu_(2)I_(5)films have been applied to the practical radiography which exhibit superior X-ray imaging performance.Our work provides a paradigm to fabricate nonpoisonous and chemically stable inorganic halide perovskite for X-ray imaging.
基金Project supported by the National Natural Science Foundation of China (60607015)
文摘Spectroscopic properties of Ce-doped yttrium orthoaluminate (Ce:YA1O3 or Ce:YAP) crystals gown by temperature gradient technique (TGT) were investigated, and the effects of the growth conditions on the properties were analyzed. Methods of optical absorption (OA), photoluminescence (PL), photoluminescence decay (PLD), X-my excited luminescence (XL) and cathodeluminescence (CL) were used in these investigations. The results showed that the absorption band peak at 202,394 and 532 nm originated from F and F^+ color center induced by the weak reducing growth atmosphere, green emission band near 500 nm derived from Ce3^+ -Ce^3+ pairs and band at 650 - 850 nm from some unintentional impurity in crystals.
基金Support by the National Natural Science Foundation of China(No.60808033)train object program of Jiangxi Province Young Scientists,Natural Science Foundation of Jiangxi Province(No.2011BAB206029,2010GQS0064 and 2008GZW0012)excellent young academic talent program of Jiangxi University of Finance and Economics
文摘The Yb3+:LiGd(WO4)2 crystal with the dimension of Ф15×35 mm3 was grown by Czochralski technique. The spectroscopic characterization and fluorescence dynamics of Yb3+ in yb3+:LiGd(WO4)2 crystal were investigated. The yb3+:LiGd(WO4)2 crystal exhibits a broad absorption band centered near 975 nm with the linewidths of 16 and 11 nm and maximal absorption cross-section of 3.60 × 10-20 and 2.90× 10-20 cm2 for π- and σ-polarization, respectively. The emission broadband has an FWHM of 47 and 45 nm with the emission cross sections of 3.92 × 10-20 and 3.34× 10-2o cm2 at 1020 nm for re- and or-polarization, respectively. The measured fluorescence lifetime is 398 gs. The blue light emission around 480 nm through cooperative upconversion from the de-excitation of excited Yb3+-Yb3+ pairs at 4 K was observed under 932-nm excitation and demonstrated.
基金supported by National Natural Science Foundation of China(Nos.12175278 and 12205072)the Comprehensive Research Facility for Fusion Technology Program of China(No.2018-000052-73-01-001228)+3 种基金Major Science and Technology Infrastructure Maintenance and Reconstruction Projects of the Chinese Academy of Sciences(2021),the University Synergy Innovation Program of Anhui Province(No.GXXT-2021-029)Anhui Provincial Key Research and Development Project(No.202104a06020021)Open Fund of the Magnetic Confinement Fusion Laboratory of Anhui Province(No.2021AMF01002)the National Magnetic Confinement Fusion Science Program of China(Nos.2019YFE03040000 and 2018YFE0303103).
文摘Inversion techniques are conducted based on the tangential x-ray crystal spectroscopy(TXCS)geometry on EAST to obtain the local profiles of ion temperature(Ti)and toroidal rotation velocity(vt).Firstly,local emissivity profiles of the impurity argon are obtained using the asymmetrical Abel inversion.Then,the local vt and Ti profiles are calculated by considering the local emissivity profiles and the TXCS detailed geometry.In addition,how the changes in the vt profiles affect the accuracy in the Ti profiles is discussed in detail.It is also found that the lineintegrated Ti profiles are becoming less accurate with the increase in the radial gradient in the local vt profiles.Nonetheless,accurate Ti radial profiles are reconstructed after considering the effects of the emissivity and velocity,which are verified by comparing the inverted vt and Ti profiles with those local profile measurements from the Charge eXchange Recombination Spectroscopy(CXRS)on EAST.
基金Supported by the Natural Science Foundation of Shandong Province (No. ZR2010EQ007)
文摘Nd3+: Li3Ba2La3(MoO4)8 crystal has been grown from a flux of Li2MoO4 by the top seeded solution growth method (TSSG) and its structure was confirmed by X-ray diffraction. The polarized absorption spectra, fluorescence spectra and fluorescence decay curve of the crystal were measured. The main spectral parameters were calculated by the Judd-Ofelt theory and compared with other Nd-doped crystals. The broad absorption bands and the large absorption cross sections around 805 nm indicate that the crystal is very suitable for diode-laser pumping. The broad emission bands around 1060 nm show that the crystal is a potential medium for tunable and short pulse lasers. The quantum efficiency of the crystal is up to 95%, which is higher than the value for Nd3+:YVO4 and Nd3+:YAG and comparable to that of other disordered molybdate crystals. The excellent spectroscopic properties show that Nd3+:Li3Ba2La3(MoO4)8 crystal may be regarded as a potential solid state laser host material for diode laser pumping.
基金Supported by the Science and Technology Research Project of Hubei Provincial Department of Education(China,No.Q20174302)the Scientific Research Foundation of Jingchu University of Technology(No.QN201602)National college students innovation and entrepreneurship training program(No.201811336003,China)
文摘Tricyanide building block K[Ru(ttpy)(CN)3] and [MnⅢ(salen)](ClO4) have been used to design and synthesize a heterobimetallic one-dimensional(1D) zigzag chain complex 1,[RuⅡ(ttpy)(CN)3 MnⅢ(salen)](ttpy = 4′-(p-tolyl)-2,2′:6′,2″-terpyridine, salen = N,N?-ethylenebis-(salicylideneaminato)dianion). Single-crystal X-ray diffraction analysis shows complex 1 crystallizes in orthorhombic Pbca space group and the asymmetric unit of 1 contains one[-NC-RuⅡ(ttpy)(CN)(m-CN)-Mn Ⅲ-(salen)-] molecule. In the structure of 1, each [Ru Ⅱ(ttpy)(CN)3]-connects two [MnⅢ(salen)]+ with two cyanide groups in a cis-conformation, and in turn each[MnⅢ(salen)]+ unit links two [RuⅡ(ttpy)(CN)3]-building blocks in a trans-conformation, resulting in a 1D [-NC-RuⅡ-CN-MnⅢ-]n chain. Furthermore, the electronic absorption spectra and luminescence spectroscopy of complex 1 have also been studied.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 11975037 and 11921006)the National Grand Instrument Project of China (Grant Nos. 2019YFF01014400 and 2019YFF01014404)。
文摘Laser-driven proton-induced x-ray emission(laser-PIXE) is a nuclear analysis method based on the compact laser ion accelerator. Due to the transient process of ion acceleration, the laser-PIXE signals are usually spurted within nanoseconds and accompanied by strong electromagnetic pulses(EMP), so traditional multi-channel detectors are no longer applicable.In this work, we designed a reflective elliptical crystal spectrometer for the diagnosis of laser-PIXE. The device can detect the energy range of 1 keV–11 ke V with a high resolution. A calibration experiment was completed on the electrostatic accelerator of Peking University using samples of Al, Ti, Cu, and ceramic artifacts. The detection efficiency of the elliptical crystal spectrometer was obtained in the order of 10-9.
文摘This paper reports the growth, X-ray diffraction and spectroscopy of Nd3+:Sr3Gd2(BO3)4 crystal. A Nd3+:Sr3Gd2(BO3)4 crystal with dimensions of φ20 × 45 mm3 has been grown by the Czochralski method. Nd3+:Sr3Gd2(BO3)4 crystal belongs to the orthorhombic system, space group Pnma (D2h) with a = 0.7401, b = 1.604 and c = 0.8755 nm. The absorption and emission spectra of Nd3+:Sr3Gd2(BO3)4 were investigated. The absorption cross section oa is 3.11 × 10^-20cm2 at 808 nm. The absorption transition at 808 nm has an FWHM of 14 nm. The luminescence lifetime τf is 51.7 μs. The emission cross section oc at 1064 nm wavelength is 1.09 × 10^-19 cm2.
基金This work was supported by Youth Innovation Promotion Association CAS,National Natural Science Foundation of China(Grant No.11705263)Shanghai Rising-Star Program(Grant No.21QA1410900)。
文摘Semiconductor materials exemplify humanity's unwavering pursuit of enhanced performance,efficiency,and functionality in electronic devices.From its early iterations to the advanced variants of today,this field has undergone an extraordinary evolution.As the reliability requirements of integrated circuits continue to increase,the industry is placing greater emphasis on the crystal qualities.Consequently,conducting a range of characterization tests on the crystals has become necessary.This paper will examine the correlation between crystal quality,device performance,and production yield,emphasizing the significance of crystal characterization tests and the important role of high-precision synchrotron radiation X-ray topography characterization in semiconductor analysis.Finally,we will cover the specific applications of synchrotron radiation characterization in the development of semiconductor materials.
基金supported by the National Natural Science Foundation of China (Nos. 20774083, 20805024, and 20971075)the Foundation of the Education Department of Zhejiang Province (No. Y201016284)+2 种基金the Ningbo Municipal Natural Science Foundation (No. 2010A610146)the applied personnel training base construction project of Ningbo (No. Jd090104)the K. C. Wong Magna Fund in Ningbo University
文摘A fluorinated tetraphenylbenzidine derivative, N,N′-diphenyl-N,N′-bis(2-fluorophenyl)-1,1′-biphenyl-4,4′-diamine (C36H26F2N2, Mr = 524.59) was synthesized via the palladiumcatalyzed Buchwald-Hartwig reaction of N,N′-diphenyl-1,1′-biphenyl-4,4′-diamine with 2-fluoroiodobenzene (yield: 75%) and structurally characterized. It crystallizes in monoclinic, space group P21/n with a = 9.820(7), b = 14.305(11), c = 10.233(8) , β = 108.973(9)o, V = 1359.3(18) 3, Z = 2, Dc = 1.282 g/cm3, μ(MoKα) = 0.084 mm-1, F(000) = 548, S = 1.018, the final R = 0.0439 and wR = 0.0928. It presents a linear centrosymmetric framework constituted by a linkage of biphenyl as a bridge and two fluorinated diphenylamine moieties. The UV-Vis absorption and fluorescence spectra of the title compound were also investigated. This compound emits intense blue fluorescence with a peak wavelength of 406 nm in film.
基金supported by the National Natural Science Foundation of China(No.91127039,51073171)Natural Science Foundation of Beijing(No.2112018)
文摘A novel palladium(II) complex [(TMEDA)Pd(anca)2].2DMSO (1, TMEDA = N,N,N',N'-tetramethylethylethylenediamine, anca = anthracene-9-carboxylic acid) was synthesized and characterized by single-crystal X-ray diffraction, 1H NMR, UV-Vis and fluorescence spectroscopy. The cell belongs to orthorhombic Aba2 space group with a = 19.698(7), b = 21.045(7) c = 9.062(3) A, Z = 4, V= 3757(2) A3, C40H46N206PdS2, Mr = 821.31, D, = 1.452 g/cm3, F(000) = 1704, the final R = 0.0272, wR = 0.0667 and GOOF = 0.999. Complex 1 exhibits an interesting distorted clip-shaped molecular configuration which is stabilized by intramolecular C-H...O hydrogen bonds. The cells are packed into a 3D supramolecular structure based on the intermolecular C-H...zr interactions which further construct the tubular channels serving as guest molecular channels to include the DMSO solvent molecules inside. Furthermore, the spectroscopic properties of 1 were also investigated.
基金Supported by the Natural Science Foundation of Henan Province (No. 102300410221)the Natural Science Foundation of Nanyang Normal University (No. ZX2010012)Project supported by the Young Core Instructor from the Education Commission of Henan Province
文摘Two novel mono-nuclear zinc(Ⅱ) complexes with oligoaniline-functionalized terpyridine ligands have been synthesized and verified by 1H-NMR,13C-NMR,Elemental Analysis (EA) and X-ray Diffraction (XRD). The UV-vis spectra show the ligand-centered (LC) π-π* transitions and intra-ligand charge transfer (1ILCT) transitions,and the 1ILCT band red-shifts with the increasing number of aromatic amine groups in the ligands. Complex [Zn(L1)2](PF6)2 with an aromatic amine group in ligand shows a strong emission peak at 523 nm in the MeCN solution at 293 K and a blue-shifted band at 517 nm in the alcoholic glass at 77 K. However,for complex [Zn(L2)2](PF6)2 containing aniline dimer modified ligand,no apparent emission can be observed in the MeCN solution at room temperature due to a PET non-radiative decay pathway. Both of them show multiplicate redox processes based on oligoaniline and terpyridine units. The shifts of redox potentials also reflect the D-A interactions between the oligoaniline units and [Zn(TPY)2]2+ core.
基金Supported by the National Natural Science Foundation of China (No. 20772152) and the State Key Laboratory of Structural Chemistry
文摘The compound 3,3'-(anthracene-9,10-diyl)bis(1-phenylpropan-1-one)(C32H26O2,Mr=442.55) has been synthesized by the reaction of 2,2'-(anthracene-9,10-diylbis(methy-lene))bis(1,3-diphenylpropane-1,3-dione) with CsCO3,and its structure was characterized by 1H NMR and single-crystal X-ray diffraction.The crystal of the title compound belongs to monoclinic,space group P21/c with a=9.154(3),b=5.2777(16),c=24.897(7) nm,β=107.337(10)°,Z=2 and V=1.1482 nm3.X-ray analysis indicates that an intermolecular hydrogen bond C(8)-H(8A)…O(1),weak C-H···π between H(9A) and the centre of anthracene rings and weak π-π interactions between two anthracene ring planes are observed.
文摘New metal complexes of N-benzyl-N-nitrosohy-droxylamine (BNHA) are isolated and characterized by elemental analysis, IR and UV-VIS spectroscopy. Spectrophotometric titration of aqueous solutions of BNHА by salts of some transition metals allowed to calculate the composition and formation constants of the metal complexes. The crystal structure of Cu (BNHА)2 is studied by X-ray diffraction. The Cu atom is coordinated by four O atoms of two bidentate ligands, which close 5-membered chelate rings. The N-O (1.306 ? - 1.320 ?) and N-N (1.274?? and 1.275? ) bond lengths indicate that π electrons are delocalized over the chelating groups. Complexes form stacks with intermolecular Cu…N contacts equal to 3.118?? and 3.306 ?.
文摘Th(BrO3)3·H2O single crystals were grown from its aqueous solution at room temperature. Single crystal XRD, Raman and FTIR techniques were used to investigate the crystal structure. The crystal structure was solved by Patterson method. The as grown crystals are in monoclinic system with space group P21/c. The unit cell parameters are a = 12.8555(18) ?, b = 7.8970(11) ?, c = 9.0716(10)?, α = 90°, β = 131.568° and γ = 90° and unit cell volume is 689.1(2)?3. Z = 8, R factor is 5.9. The Raman and FTIR studies indicate the lowering of symetry of bromate anion from C3V to C1. Hydrogen bonds with varying strengths are present in the crystal. The centrosymmetric space group P21/c of the crystal is confirmed by the non-coincidence of majority of Raman and IR bands.
基金Partial support of this work by the Turkish Academy of Sciences and the Scientific and Technological Research Council of Turkey(TUBITAK,Project No:105M357)is gratefully acknowledgedL.T.Y ildirim thanks Hacettepe University Scientific Research Unit(grant,No.04 A602004)for financial support.
文摘A novel and simple synthetic way using NaBH4 in the mixure of H2O-THF was applied to prepare 1,2-bis(diphenylphosphinoborane)ethane, dppe(BH3)2, in high yield and purity. The phosphanylborohydride compound dppe(BH3)2 was isolated in the form of colorless crystals and characterized by single crystal X-ray diffraction, 1H, 13C, 31P and 11B NMR spectroscopy. Prismatic colorless crystals of dppe(BH3)2 were obtained in monoclinic crystal system and space group P21 with two asymmetric units in the unit cell. Lattice parameters were: a = 11.657(2), b = 17.237(2), c = 12.764(2) ?, β = 98.735(14)°, 2535.0(7) ?
文摘New transition metal complex of Cobalt(III) of the ligand (E)-3-(1-(2-aminoethylimino)ethyl)-4-hydroxy-2H-chromen-2-one, derived from condensation of ethylene diamine with 3-acetyl-4-hydroxy-chromene-2-one have been synthesized by reaction of cobalt(III) salt and the ligand, in amounts equal to metal-ligand molar ratio of 1:2. Both the Schiff base and the complex of Co(III) were characterized by IR, UV-Vis, 1H NMR- and 13C NMR-spectroscopy techniques. Single crystal X-ray diffraction investigation, at low temperature T = 120 K, shows that the cobalt complex is triclinic P-1, a = 10.426(5) ?, b = 11.3234(2) ?, c = 15.729(5) ?, α(°) = 70.102(4), β(°) = 86.049(4), γ(°) = 82.497(4), Z = 2, and its structure consists of isolated [Co(III)(C13H13N2O3)2]+ complex cations with distorted octahedral geometry, ClO-4 counter anions, acetone solvent and water molecules. The crystal cohesion is stabilized by hydrogen bonds between ligands and water molecules, and ionic interactions between complex cations and counter anions.