An efficient and mild method for the direct conversion of alcohols into N-alkylphthalimides using 2,4,6-trichloro-1,3,5-triazine and dimethylformamide was described.The reaction was preceded via(alcoxymethylene) dimet...An efficient and mild method for the direct conversion of alcohols into N-alkylphthalimides using 2,4,6-trichloro-1,3,5-triazine and dimethylformamide was described.The reaction was preceded via(alcoxymethylene) dimethylammonium chloride intermediate and produced corresponding N-alkylphthalimides in good-to-excellent yields.展开更多
The initial decomposition of methylamine on Mo（100） surface has been investigated by self-consistent （GGA-PW91） density functional theory combined with periodic slab model. The adsorption energies of possible spec...The initial decomposition of methylamine on Mo（100） surface has been investigated by self-consistent （GGA-PW91） density functional theory combined with periodic slab model. The adsorption energies of possible species and the activation energies for possible elementary reactions involved are obtained in the present work. Our results indicate that the barriers decreased with the order of C-NN-HC-H. In addition, metastable adsorption of the abstracted hydrogen atom on the hollow site in the final state is also considered for the N-H and C-H bond breaking. For the C-H bond cleavage, the reaction barrier that the abstracted hydrogen located on the hollow site in the final state is lower than that on the bridge site. However, for the N H bond breaking, the barriers are alike for the abstracted hydrogen on both hollow and bridge sites in the final state.展开更多
The quality of MAPbI3 film prepared by solvent engineering process highly depends on environment and antisolvent control.Here,we provided a simple methylamine chloride(MACl)solution treatment using a two-step process ...The quality of MAPbI3 film prepared by solvent engineering process highly depends on environment and antisolvent control.Here,we provided a simple methylamine chloride(MACl)solution treatment using a two-step process to enlarge the perovskite crystal grain sizes to more than 1 lm.Other than treatment on the film surface,the MACl solution diffuses into the MAPbI_(3) films to assist the recrystallization of small crystal at the bottom of perovskite film.The imitative contact between perovskite and substrate is formed.Meanwhile,the enlargement of grain size and ten times enhancement of crystalline reduce trap-assisted recombination of perovskite films.Thus,the significant improvement of cell efficiency of 20.89%as well as device stability is obtained with the MACl treatment.展开更多
Density,viscosity and ultrasonic v elocity of solutions of four Schiff bases in 1,4-dioxane and dimethylfor -mamide(DMF )were measured at 308.15K.Various acoustical properties such as specific impedance(Z),adiabatic c...Density,viscosity and ultrasonic v elocity of solutions of four Schiff bases in 1,4-dioxane and dimethylfor -mamide(DMF )were measured at 308.15K.Various acoustical properties such as specific impedance(Z),adiabatic compressibility(κ s ),Rao’s molar sound function(R m ),the van der Waals constant (b),molar compressibility(W),intermolecular free length(L f ),relaxation strength(r),solvation number(S n ),were calculated.The results are in terpret-ed in terms of molecular interactions occurring in the solutions.展开更多
In-situ synthesis of ternary europium complex with thenoyltrifluoacetone (TTA) and 1,10-phenanthroline (phen) in titania matrix in the presence of dimethylformamide (DMF) by a sol-gel process was described, which was ...In-situ synthesis of ternary europium complex with thenoyltrifluoacetone (TTA) and 1,10-phenanthroline (phen) in titania matrix in the presence of dimethylformamide (DMF) by a sol-gel process was described, which was confirmed by the luminescence excitation spectra and infrared spectra. The titania gel that contains europium complex exhibits Eu3+ characteristic emission bands and presents a longer fluorescence lifetime than the pure complexes dissolved in ethanol solution. The concentration effect on the luminescence intensity was also investigated.展开更多
N-pivot lariat ethers with picrylamino group as a chromophore (1, 2 and 3) have been prepared by reaction of N-(4-aminoaryl)monoaza crown ethers with picryl chrolide, and the selective coloration of 1, 2 and 3 for alk...N-pivot lariat ethers with picrylamino group as a chromophore (1, 2 and 3) have been prepared by reaction of N-(4-aminoaryl)monoaza crown ethers with picryl chrolide, and the selective coloration of 1, 2 and 3 for alkali metal salts and amines has been studied by UV-Vis spectra.展开更多
The elexctrochemical properties of Dy (III), Ni(II) + Ni(II) indimethylformamide were studied by cyclic voltammetry on Pt or Cuelectrode. Black, metallic lustered, compact and well adhesive Dy-Nialloy films can be co-...The elexctrochemical properties of Dy (III), Ni(II) + Ni(II) indimethylformamide were studied by cyclic voltammetry on Pt or Cuelectrode. Black, metallic lustered, compact and well adhesive Dy-Nialloy films can be co-deposited on Cu electrode bysweeping-potential-deposition method within some potentials. SEM,EDAX and XRD were used to analyze the alloy films. The Dy content inthe Dy-Ni alloy film is up to 56.91/100 (mass fraction) and the Dy-Ni alloy films are amorphous.展开更多
Seven novel platinum （Ⅱ） complexes [ Pt（Ⅱ） （NH3） （CH3NH2）X2] （Ⅰ-Ⅶ ） （ X： CH3COO^-, CH2CICOO^- , CHCI2COO^- , C6H5-COO^- , p-CH3O--C6H4-COO^- , p-NH2-C6H4-COO^- , p-NO2--C6H4- COO^-） were prepared and ...Seven novel platinum （Ⅱ） complexes [ Pt（Ⅱ） （NH3） （CH3NH2）X2] （Ⅰ-Ⅶ ） （ X： CH3COO^-, CH2CICOO^- , CHCI2COO^- , C6H5-COO^- , p-CH3O--C6H4-COO^- , p-NH2-C6H4-COO^- , p-NO2--C6H4- COO^-） were prepared and characterized by means of elemental analysis, molar conductivity, thermal analysis, IR, UV, and ^1H NMR spectrometries. The cytotoxicity against HCT-8, BGC-823, MCF-7, EJ, and HL-60 cell lines increases in the following sequence： cisplatin 〉 Ⅳ 〉 Ⅴ 〉 Ⅵ 〉 Ⅶ 〉 Ⅰ 〉 Ⅱ 〉 Ⅲ. Moreover, the complexes （ Ⅰ --Ⅻ） display substantially greater activities agaist EJ and HL-60 cell lines than those against the cell lines from other carcinomas. They can induce a concentration-dependent accumulation of HL-60 cells in the G2/M phase of the cell cycle as cisplatin. There is no significant correlation between total DNA platination levels and cytotoxicity of the complexes.展开更多
Upscaling perovskite solar cell fabrication is one of the key challenges in the pathway for commercialization.The slow evaporation of frequently used solvents(DMF or DMSO) limits the fast perovskite layer crystallizat...Upscaling perovskite solar cell fabrication is one of the key challenges in the pathway for commercialization.The slow evaporation of frequently used solvents(DMF or DMSO) limits the fast perovskite layer crystallization,hindering their implementation in large scale deposition methods.Alternatively,methylamine-based precursors have demonstrated rapid crystallization,leading to uniform and specular films.Nonetheless,their application has been limited to MAPbI3 perovskites with limited efficiency and stability.In this work,we report the requirements for stabilizing α-phase of mixed cation perovskites with high amount of formamidinium by using a methylamine-based precursor.We found that even though,there are many methods for incorporating the methylamine(MA) in precursors or films;the MA content determines stabilization of the α-phase and therefore the viscous-solution route is the only method to incorporate high amounts of MA.At low amounts of MA,perovskite tend to crystallize in 1D dimensional FA_(3)(MA)PbI5 phases due to the incomplete solvation of the PbI6-clusters.In contrast,high MA ratio induces a full solvation of the clusters,leading to a rapid crystallization and a full stabilization of the active 3D α-phase.These results open a window in the development and understanding of new precursors for the fabrication of high efficient,stable and scalable perovskite devices.展开更多
Enantiomers of a-substituted-(2-pyridyl)-methylarfdnes uere separated on SC -7 gas chromatograph with a 20m×0.25mm Chirasil-Val capIlary column,Carrier gas was nitro- gen or hydrogen.The resolution factors(ri.s) ...Enantiomers of a-substituted-(2-pyridyl)-methylarfdnes uere separated on SC -7 gas chromatograph with a 20m×0.25mm Chirasil-Val capIlary column,Carrier gas was nitro- gen or hydrogen.The resolution factors(ri.s) were 1.02 to 1.06.Enantiomers of pyridyl anines were separated to and near to base line.展开更多
Although perovskite solar cells containing methylamine cation can show high power conversion efficiency,stability is a concern.Here,methylamine-free perovskite material Csx FA1–x PbI3 was synthesized by a one-step me...Although perovskite solar cells containing methylamine cation can show high power conversion efficiency,stability is a concern.Here,methylamine-free perovskite material Csx FA1–x PbI3 was synthesized by a one-step method.In addition,we incorporated smaller cadmium ions into mixed perovskite lattice to partially replace Pb ions to address the excessive internal strain in perovskite structure.We have found that the introduction of Cd can improve the crystallinity and the charge carrier lifetime of perovskite films.Consequently,a power conversion efficiency as high as 20.59%was achieved.More importantly,the devices retained 94%of their initial efficiency under 1200 h of continuous illumination.展开更多
The cyclic voltammetry, current time curve at potential step and potential time curve of galvanostatic method were used to investigate the electrochemical behavior of Er(Ⅲ) in ErCl 3 LiClO 4 DMF(N, N dimethylformamid...The cyclic voltammetry, current time curve at potential step and potential time curve of galvanostatic method were used to investigate the electrochemical behavior of Er(Ⅲ) in ErCl 3 LiClO 4 DMF(N, N dimethylformamide) system on Pt and Cu electrodes. Results indicate that the electroreducation of Er(Ⅲ) to Er(0) is irreversible on Pt and Cu electrodes, the diffusion coefficient and electron transfer coefficient of Er(Ⅲ) in 0.01 mol/L ErCl 3 0.1 mol/L LiClO 4 DMF system at 303 K are 1.96×10 -6 cm 2·s -1 and 0.081 respectively. The Er metal film was prepared by galvanostatic electrolysis on Cu electrode in ErCl 3 LiClO 4 DMF system at 40 A·m -2 (current density). The deposites composed of Er over 95%(mass fraction) were obtained.展开更多
In this study sodium alginate (NaAlg)/poly (vinyl pyrrolidone) (PVP) blend membranes were prepared and crosslinked with CaCl2 (0.1 Molarity (M)) for the separation of aqueous/dimethylformamide (DMF) mixtures. Membrane...In this study sodium alginate (NaAlg)/poly (vinyl pyrrolidone) (PVP) blend membranes were prepared and crosslinked with CaCl2 (0.1 Molarity (M)) for the separation of aqueous/dimethylformamide (DMF) mixtures. Membranes were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and their performance was examined by varying experimental parameters such as feed composition (0 - 100 wt%), operating temperature (30℃ - 50℃) and membrane thickness (30 - 90 micrometer (μm)). Blending NaAlg with PVP, decreased separation factor whereas increased the permeation rate as the permeation temperature was increased in Vapor Permeation (VP) and Vapor Permeation with Temperature Difference (TDVP) methods. In the TDVP method, the separation factors increased and the permeation rates decreased as the temperature of the membrane surrounding is decreased. The highest separation factor of 60 was obtained in TDVP method for 90 wt% DMF concentration in the feed.展开更多
N,N-二甲基甲酰胺(DMF)作为有机溶剂在化工领域得到了广泛的应用。本研究通过对小试升流式厌氧污泥床(UASB)反应器处理高浓度DMF工业废水的实验进行评估。实验中,UASB在有限有机负荷率(OLR)范围1.57~9.59 kg COD/(m^(3)·d)下运行,...N,N-二甲基甲酰胺(DMF)作为有机溶剂在化工领域得到了广泛的应用。本研究通过对小试升流式厌氧污泥床(UASB)反应器处理高浓度DMF工业废水的实验进行评估。实验中,UASB在有限有机负荷率(OLR)范围1.57~9.59 kg COD/(m^(3)·d)下运行,将水力停留时间(HRT)由48 h缩短至8 h,去除效率优良,达到95%以上。利用经验方程对DMF废水处理过程的CO_(2)排放量和生物能源产生量进行了估算和评估,相比传统的活性污泥(CAS)工艺,UASB工艺具有明显优势,能够回收能源并减少CO_(2)排放,其正净能量潜力为0.061 kW·h/m^(3),同时还显著减少了6.18 kg/m^(3)的CO_(2)排放量。本研究的结果证明了UASB工艺在处理DMF废水方面的潜力和可行性,并促进了碳中和理念在废水处理中的推广。展开更多
基金Shahid Chamran University Research Council,Ahvaz,for financial support of this investigation(No.87)
文摘An efficient and mild method for the direct conversion of alcohols into N-alkylphthalimides using 2,4,6-trichloro-1,3,5-triazine and dimethylformamide was described.The reaction was preceded via(alcoxymethylene) dimethylammonium chloride intermediate and produced corresponding N-alkylphthalimides in good-to-excellent yields.
基金supported by the National Natural Science Foundation of China (Grants No. 21073113)the Intramural Foundation of Shanxi Datong University
文摘The initial decomposition of methylamine on Mo（100） surface has been investigated by self-consistent （GGA-PW91） density functional theory combined with periodic slab model. The adsorption energies of possible species and the activation energies for possible elementary reactions involved are obtained in the present work. Our results indicate that the barriers decreased with the order of C-NN-HC-H. In addition, metastable adsorption of the abstracted hydrogen atom on the hollow site in the final state is also considered for the N-H and C-H bond breaking. For the C-H bond cleavage, the reaction barrier that the abstracted hydrogen located on the hollow site in the final state is lower than that on the bridge site. However, for the N H bond breaking, the barriers are alike for the abstracted hydrogen on both hollow and bridge sites in the final state.
基金financially supported by the National Key R&D Program of China (Grant No. 2020YFB1506404)the 111 Project (Grant No. B16016)+1 种基金the National Natural Science Foundation of China (Grant Nos. 51961165106, 51572080 and 61904053)the Fundamental Research Funds for the Central Universities (Grant Nos. 2019MS026, 2019MS027 and 2020MS080)。
文摘The quality of MAPbI3 film prepared by solvent engineering process highly depends on environment and antisolvent control.Here,we provided a simple methylamine chloride(MACl)solution treatment using a two-step process to enlarge the perovskite crystal grain sizes to more than 1 lm.Other than treatment on the film surface,the MACl solution diffuses into the MAPbI_(3) films to assist the recrystallization of small crystal at the bottom of perovskite film.The imitative contact between perovskite and substrate is formed.Meanwhile,the enlargement of grain size and ten times enhancement of crystalline reduce trap-assisted recombination of perovskite films.Thus,the significant improvement of cell efficiency of 20.89%as well as device stability is obtained with the MACl treatment.
文摘Density,viscosity and ultrasonic v elocity of solutions of four Schiff bases in 1,4-dioxane and dimethylfor -mamide(DMF )were measured at 308.15K.Various acoustical properties such as specific impedance(Z),adiabatic compressibility(κ s ),Rao’s molar sound function(R m ),the van der Waals constant (b),molar compressibility(W),intermolecular free length(L f ),relaxation strength(r),solvation number(S n ),were calculated.The results are in terpret-ed in terms of molecular interactions occurring in the solutions.
文摘In-situ synthesis of ternary europium complex with thenoyltrifluoacetone (TTA) and 1,10-phenanthroline (phen) in titania matrix in the presence of dimethylformamide (DMF) by a sol-gel process was described, which was confirmed by the luminescence excitation spectra and infrared spectra. The titania gel that contains europium complex exhibits Eu3+ characteristic emission bands and presents a longer fluorescence lifetime than the pure complexes dissolved in ethanol solution. The concentration effect on the luminescence intensity was also investigated.
文摘N-pivot lariat ethers with picrylamino group as a chromophore (1, 2 and 3) have been prepared by reaction of N-(4-aminoaryl)monoaza crown ethers with picryl chrolide, and the selective coloration of 1, 2 and 3 for alkali metal salts and amines has been studied by UV-Vis spectra.
基金financially supported by the Science Foundation of Guangdong Province (No. 011215)
文摘The elexctrochemical properties of Dy (III), Ni(II) + Ni(II) indimethylformamide were studied by cyclic voltammetry on Pt or Cuelectrode. Black, metallic lustered, compact and well adhesive Dy-Nialloy films can be co-deposited on Cu electrode bysweeping-potential-deposition method within some potentials. SEM,EDAX and XRD were used to analyze the alloy films. The Dy content inthe Dy-Ni alloy film is up to 56.91/100 (mass fraction) and the Dy-Ni alloy films are amorphous.
文摘Seven novel platinum （Ⅱ） complexes [ Pt（Ⅱ） （NH3） （CH3NH2）X2] （Ⅰ-Ⅶ ） （ X： CH3COO^-, CH2CICOO^- , CHCI2COO^- , C6H5-COO^- , p-CH3O--C6H4-COO^- , p-NH2-C6H4-COO^- , p-NO2--C6H4- COO^-） were prepared and characterized by means of elemental analysis, molar conductivity, thermal analysis, IR, UV, and ^1H NMR spectrometries. The cytotoxicity against HCT-8, BGC-823, MCF-7, EJ, and HL-60 cell lines increases in the following sequence： cisplatin 〉 Ⅳ 〉 Ⅴ 〉 Ⅵ 〉 Ⅶ 〉 Ⅰ 〉 Ⅱ 〉 Ⅲ. Moreover, the complexes （ Ⅰ --Ⅻ） display substantially greater activities agaist EJ and HL-60 cell lines than those against the cell lines from other carcinomas. They can induce a concentration-dependent accumulation of HL-60 cells in the G2/M phase of the cell cycle as cisplatin. There is no significant correlation between total DNA platination levels and cytotoxicity of the complexes.
基金financial support provided by the committee for the development of research(CODI) of the Universidad de Antioquia,in the framework of the project 2017-16000the financial support of the Colombia Scientific Program within the framework of the call Ecosistema Cientifíco(Contract FP44842-218-2018)。
文摘Upscaling perovskite solar cell fabrication is one of the key challenges in the pathway for commercialization.The slow evaporation of frequently used solvents(DMF or DMSO) limits the fast perovskite layer crystallization,hindering their implementation in large scale deposition methods.Alternatively,methylamine-based precursors have demonstrated rapid crystallization,leading to uniform and specular films.Nonetheless,their application has been limited to MAPbI3 perovskites with limited efficiency and stability.In this work,we report the requirements for stabilizing α-phase of mixed cation perovskites with high amount of formamidinium by using a methylamine-based precursor.We found that even though,there are many methods for incorporating the methylamine(MA) in precursors or films;the MA content determines stabilization of the α-phase and therefore the viscous-solution route is the only method to incorporate high amounts of MA.At low amounts of MA,perovskite tend to crystallize in 1D dimensional FA_(3)(MA)PbI5 phases due to the incomplete solvation of the PbI6-clusters.In contrast,high MA ratio induces a full solvation of the clusters,leading to a rapid crystallization and a full stabilization of the active 3D α-phase.These results open a window in the development and understanding of new precursors for the fabrication of high efficient,stable and scalable perovskite devices.
基金The project is supported by National Nature science Foundation of China.
文摘Enantiomers of a-substituted-(2-pyridyl)-methylarfdnes uere separated on SC -7 gas chromatograph with a 20m×0.25mm Chirasil-Val capIlary column,Carrier gas was nitro- gen or hydrogen.The resolution factors(ri.s) were 1.02 to 1.06.Enantiomers of pyridyl anines were separated to and near to base line.
基金supported by National Natural Science Foundation of China (Grant Numbers : 61634001, 61574133)
文摘Although perovskite solar cells containing methylamine cation can show high power conversion efficiency,stability is a concern.Here,methylamine-free perovskite material Csx FA1–x PbI3 was synthesized by a one-step method.In addition,we incorporated smaller cadmium ions into mixed perovskite lattice to partially replace Pb ions to address the excessive internal strain in perovskite structure.We have found that the introduction of Cd can improve the crystallinity and the charge carrier lifetime of perovskite films.Consequently,a power conversion efficiency as high as 20.59%was achieved.More importantly,the devices retained 94%of their initial efficiency under 1200 h of continuous illumination.
文摘The cyclic voltammetry, current time curve at potential step and potential time curve of galvanostatic method were used to investigate the electrochemical behavior of Er(Ⅲ) in ErCl 3 LiClO 4 DMF(N, N dimethylformamide) system on Pt and Cu electrodes. Results indicate that the electroreducation of Er(Ⅲ) to Er(0) is irreversible on Pt and Cu electrodes, the diffusion coefficient and electron transfer coefficient of Er(Ⅲ) in 0.01 mol/L ErCl 3 0.1 mol/L LiClO 4 DMF system at 303 K are 1.96×10 -6 cm 2·s -1 and 0.081 respectively. The Er metal film was prepared by galvanostatic electrolysis on Cu electrode in ErCl 3 LiClO 4 DMF system at 40 A·m -2 (current density). The deposites composed of Er over 95%(mass fraction) were obtained.
基金Gazi University Research Fund for the support of this study.
文摘In this study sodium alginate (NaAlg)/poly (vinyl pyrrolidone) (PVP) blend membranes were prepared and crosslinked with CaCl2 (0.1 Molarity (M)) for the separation of aqueous/dimethylformamide (DMF) mixtures. Membranes were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and their performance was examined by varying experimental parameters such as feed composition (0 - 100 wt%), operating temperature (30℃ - 50℃) and membrane thickness (30 - 90 micrometer (μm)). Blending NaAlg with PVP, decreased separation factor whereas increased the permeation rate as the permeation temperature was increased in Vapor Permeation (VP) and Vapor Permeation with Temperature Difference (TDVP) methods. In the TDVP method, the separation factors increased and the permeation rates decreased as the temperature of the membrane surrounding is decreased. The highest separation factor of 60 was obtained in TDVP method for 90 wt% DMF concentration in the feed.
