The structure of complexes Dy[CH 2(CH 2) 4CONC 4H 9] 3(NO 3) 3 and La[CH 2(CH 2) 4CONC 4H 9] 3(NO 3) 3 was studied by single crystal X ray diffraction. The two compounds are isostructural and all form...The structure of complexes Dy[CH 2(CH 2) 4CONC 4H 9] 3(NO 3) 3 and La[CH 2(CH 2) 4CONC 4H 9] 3(NO 3) 3 was studied by single crystal X ray diffraction. The two compounds are isostructural and all form monoclinic crystal with space group P 2 1/ c . The crystal data Dy: a =1 8564(3)[1 8857(2)] nm, b =0 9769(2) [0 9834(1)] nm, c =2 1863(6)[2 2008(7)] nm, β =96 08(2)[95 72(2)]°, V =3 942(1)[4 061(1)] nm 3, Z =4. Dy 3+ [La 3+ ] is coordinated through three carbonyls of the three organic ligands and the three nitrates are all bidentate. So each Dy 3+ [La 3+ ] is coordinated by nine oxygen atoms which form a distorted tricapped trigonal prism.展开更多
The rare occurrence of te halos produced by cirrus ice crystals in nature has been investigated by modelling the incident solar (visible) light scattering angular distribution using the Monte Carlo/ray tracing method....The rare occurrence of te halos produced by cirrus ice crystals in nature has been investigated by modelling the incident solar (visible) light scattering angular distribution using the Monte Carlo/ray tracing method.The results show that the irregular shapes of ice crystals and large population of small ice particles in cirrus are responsible forthe rare occurrence of halos.展开更多
Based on the detailed geological investigation and record of galleries and drill holes, a new idea has been advanced that granodiorite is earlier than quartz monzodiorite porphyry. Both of them are products of two dif...Based on the detailed geological investigation and record of galleries and drill holes, a new idea has been advanced that granodiorite is earlier than quartz monzodiorite porphyry. Both of them are products of two different magmatic intrusive activities. The analysis results of trace elements show that the Sr content is beyond any other crustal rock and the Th content is beyond that of Ta. The whole-rock analysis indicates that rockbody is rich in CaO and poor in K2O. In the composition of Pb istope of rockbody, the ratio of 207 Pb to 204Pb is less than 15. 60. All these show that the magma mainly comes from the upper mantle. Ti,Zr,Cr,Nb trace elements and the relation between the Gardini index(τ) and the Rittmann index(σ) indicate that the rockbodies are formed in the orogenic belt and island arc tectonic setting. The summation (2REE) and the characteristic value(m( La)/m( Yb)) of the rare earth elements show that the original rock is alkalic basalt. The analysis of the characteristic values of REE and the quantitative modeling calculation indicate that the rock-forming process is dominated by mixed crystallization. According to the analysis on the rock-forming order, magmatic source, tectonic setting and rock-forming process, combined with the achievements of regional rock-controlling structures and division of sublayer of crust, it is believed that Fenghuangshan rock body derives from the deep-seated alkalic basalt magma. The rock-forming process has undertaken sialic and calcareous assimilation and contamination of two different degrees. The rock-forming model belongs to the typical assimilation and fractional cryatalization mechanism.展开更多
The low-cost and scalable printable mesoporous perovskite solar cells(p-MPSCs) face significant challenges in regulating perovskite crystal growth due to their nanoscale mesoporous scaffold structure, which limits the...The low-cost and scalable printable mesoporous perovskite solar cells(p-MPSCs) face significant challenges in regulating perovskite crystal growth due to their nanoscale mesoporous scaffold structure, which limits the improvement of device power conversion efficiency(PCE). In particular, the most commonly used solvents, N,N-dimethylformamide(DMF) and dimethyl sulfoxide(DMSO), have a single chemical interaction with the precursor components and high volatility, which is insufficient to self-regulate the perovskite crystallization process, leading to explosive nucleation and limited growth within mesoporous scaffolds. Here, we report a mixed solvent system composed of methylamine formaldehyde(MAFa)-based ionic liquid and acetonitrile(ACN) with the strong C=O–Pb coordination and N–H···I hydrogen bonding with perovskite components. We found that the mixed solvent system is beneficial for the precursor solution to homogeneously penetrate into the mesoporous scaffold,and the strong C=O–Pb coordination and N–H···I hydrogen bonding interaction can promote the oriented growth of perovskite crystals. This synergistic effect increased the PCE of the p-MPSCs from 17.50% to 19.21%, which is one of the highest records for p-MPSC in recent years. Additionally, the devices exhibit positive environmental stability, retaining over 90% of the original PCE after 1,200 h of aging under AM 1.5 illumination conditions at 55 ℃ and 55% humidity.展开更多
A two-dimensional network compound [Ce(DMF)4(H2O)][α-BW12O40]·H2O·(HDMA)2 (HDMA = protoned dimethylamine, DMF = N,N-dimethylformamide) was synthesized from α-H5BW12O40·nH2O, Ce(NO3)3·6H2O and DMF...A two-dimensional network compound [Ce(DMF)4(H2O)][α-BW12O40]·H2O·(HDMA)2 (HDMA = protoned dimethylamine, DMF = N,N-dimethylformamide) was synthesized from α-H5BW12O40·nH2O, Ce(NO3)3·6H2O and DMF and characterized by IR, UV spectra and TG-DTA. The result of the X-ray single crystal diffraction indicates that the crystal is monoclinic, space group P21/n, with unit cell dimensional: a = 1.1983(3), b = 2.4216(5), c = 1.9517(4) nm, β = 92.91(3)°, Z = 4, R1 = 0.07710, wR2 = 0.1416. Structural analysis indicates that every [Ce(DMF)4(H2O)]3+ building block is surrounded by three adjacent [α-BW12O40]5- polyanions, meanwhile, every [α-BW12O40]5- polyanion interconnects with three neighboring [Ce(DMF)4(H2O)]3+ subunits, by making use of which two-dimensional network structure can be constructed. The result of thermogravimetric analysis manifests that the title compound has two-stage weight loss and the decomposition temperature of the title polyanionic framework is 560℃ . The electrochemical analysis shows the title polyanion has three-step redox processes in the pH = 4―7 media.展开更多
文摘The structure of complexes Dy[CH 2(CH 2) 4CONC 4H 9] 3(NO 3) 3 and La[CH 2(CH 2) 4CONC 4H 9] 3(NO 3) 3 was studied by single crystal X ray diffraction. The two compounds are isostructural and all form monoclinic crystal with space group P 2 1/ c . The crystal data Dy: a =1 8564(3)[1 8857(2)] nm, b =0 9769(2) [0 9834(1)] nm, c =2 1863(6)[2 2008(7)] nm, β =96 08(2)[95 72(2)]°, V =3 942(1)[4 061(1)] nm 3, Z =4. Dy 3+ [La 3+ ] is coordinated through three carbonyls of the three organic ligands and the three nitrates are all bidentate. So each Dy 3+ [La 3+ ] is coordinated by nine oxygen atoms which form a distorted tricapped trigonal prism.
文摘The rare occurrence of te halos produced by cirrus ice crystals in nature has been investigated by modelling the incident solar (visible) light scattering angular distribution using the Monte Carlo/ray tracing method.The results show that the irregular shapes of ice crystals and large population of small ice particles in cirrus are responsible forthe rare occurrence of halos.
基金the National "973" Project (No. G1999043206) the National Scientific Project for Tackcling Key Problems(No. 2001BA609A-06-02).
文摘Based on the detailed geological investigation and record of galleries and drill holes, a new idea has been advanced that granodiorite is earlier than quartz monzodiorite porphyry. Both of them are products of two different magmatic intrusive activities. The analysis results of trace elements show that the Sr content is beyond any other crustal rock and the Th content is beyond that of Ta. The whole-rock analysis indicates that rockbody is rich in CaO and poor in K2O. In the composition of Pb istope of rockbody, the ratio of 207 Pb to 204Pb is less than 15. 60. All these show that the magma mainly comes from the upper mantle. Ti,Zr,Cr,Nb trace elements and the relation between the Gardini index(τ) and the Rittmann index(σ) indicate that the rockbodies are formed in the orogenic belt and island arc tectonic setting. The summation (2REE) and the characteristic value(m( La)/m( Yb)) of the rare earth elements show that the original rock is alkalic basalt. The analysis of the characteristic values of REE and the quantitative modeling calculation indicate that the rock-forming process is dominated by mixed crystallization. According to the analysis on the rock-forming order, magmatic source, tectonic setting and rock-forming process, combined with the achievements of regional rock-controlling structures and division of sublayer of crust, it is believed that Fenghuangshan rock body derives from the deep-seated alkalic basalt magma. The rock-forming process has undertaken sialic and calcareous assimilation and contamination of two different degrees. The rock-forming model belongs to the typical assimilation and fractional cryatalization mechanism.
基金financially supported by the Natural Science Foundation of China (62288102, 22379067, 52172198, 61705102, 62205142 and 52302266)the National Key R&D Program of China (2023YFB4204500)+4 种基金the Jiangsu Provincial Departments of Science and Technology (BE2022023, BK20220010, and BZ2023060)the Innovation Project of Optics Valley Laboratory (OVL2021BG006)the Open Project Program of Wuhan National Laboratory for Optoelectronics (2021WNLOKF003)the Natural Science Basic Research Plan in Shaanxi Province of China (2021JLM-43)the Joint Research Funds of Department of Science & Technology of Shaanxi Province and Northwestern Polytechnical University (2020GXLH-Z-007 and 2020GXLH-Z-014)。
文摘The low-cost and scalable printable mesoporous perovskite solar cells(p-MPSCs) face significant challenges in regulating perovskite crystal growth due to their nanoscale mesoporous scaffold structure, which limits the improvement of device power conversion efficiency(PCE). In particular, the most commonly used solvents, N,N-dimethylformamide(DMF) and dimethyl sulfoxide(DMSO), have a single chemical interaction with the precursor components and high volatility, which is insufficient to self-regulate the perovskite crystallization process, leading to explosive nucleation and limited growth within mesoporous scaffolds. Here, we report a mixed solvent system composed of methylamine formaldehyde(MAFa)-based ionic liquid and acetonitrile(ACN) with the strong C=O–Pb coordination and N–H···I hydrogen bonding with perovskite components. We found that the mixed solvent system is beneficial for the precursor solution to homogeneously penetrate into the mesoporous scaffold,and the strong C=O–Pb coordination and N–H···I hydrogen bonding interaction can promote the oriented growth of perovskite crystals. This synergistic effect increased the PCE of the p-MPSCs from 17.50% to 19.21%, which is one of the highest records for p-MPSC in recent years. Additionally, the devices exhibit positive environmental stability, retaining over 90% of the original PCE after 1,200 h of aging under AM 1.5 illumination conditions at 55 ℃ and 55% humidity.
基金This work was supported by the National Natural Science Foundation of China (Grant No.20571023) the Doctor Foundation of Education+1 种基金 the Out-standing Youth Foundation of Henan Province the Natural Science Foundation of Henan Province and Henan Innovation Project for University Prominent Research Talent.
文摘A two-dimensional network compound [Ce(DMF)4(H2O)][α-BW12O40]·H2O·(HDMA)2 (HDMA = protoned dimethylamine, DMF = N,N-dimethylformamide) was synthesized from α-H5BW12O40·nH2O, Ce(NO3)3·6H2O and DMF and characterized by IR, UV spectra and TG-DTA. The result of the X-ray single crystal diffraction indicates that the crystal is monoclinic, space group P21/n, with unit cell dimensional: a = 1.1983(3), b = 2.4216(5), c = 1.9517(4) nm, β = 92.91(3)°, Z = 4, R1 = 0.07710, wR2 = 0.1416. Structural analysis indicates that every [Ce(DMF)4(H2O)]3+ building block is surrounded by three adjacent [α-BW12O40]5- polyanions, meanwhile, every [α-BW12O40]5- polyanion interconnects with three neighboring [Ce(DMF)4(H2O)]3+ subunits, by making use of which two-dimensional network structure can be constructed. The result of thermogravimetric analysis manifests that the title compound has two-stage weight loss and the decomposition temperature of the title polyanionic framework is 560℃ . The electrochemical analysis shows the title polyanion has three-step redox processes in the pH = 4―7 media.