Sulphur-containing aromatic amines were prepared efficiently in good to excellent yields by reduction of the corresponding sulphur-containing aromatic nitro compounds with hydrazine hydrate in the presence of iron(Ⅲ...Sulphur-containing aromatic amines were prepared efficiently in good to excellent yields by reduction of the corresponding sulphur-containing aromatic nitro compounds with hydrazine hydrate in the presence of iron(Ⅲ) oxide-MgO catalyst. The catalyst exhibited high activity and stability for the reduction of sulphur-containing aromatic nitro compounds. The yields of sulphur-containing aromatic amines were up to 91-99 % at 355 K after reduction for 1-4 h over this catalyst.展开更多
Sulphur-containing aromatic nitro compounds were rapidly reduced to the corresponding amines in high yields by employing hydrazine hydrate as a hydrogen donor in the presence of iron oxide hydroxide catalyst. It was w...Sulphur-containing aromatic nitro compounds were rapidly reduced to the corresponding amines in high yields by employing hydrazine hydrate as a hydrogen donor in the presence of iron oxide hydroxide catalyst. It was worth noting that the catalyst exhibited extremely high activity. The reduction could be completed within 20-50 min and the yields were up to 97-99 %.展开更多
Ethane conversion to ethylene and aromatics over Zn/zeolite catalysts is a promising technology for efficient exploitation of light alkanes. However, the reaction faces two major hurdles including the limited ethane c...Ethane conversion to ethylene and aromatics over Zn/zeolite catalysts is a promising technology for efficient exploitation of light alkanes. However, the reaction faces two major hurdles including the limited ethane conversion due to thermodynamics and the drastic catalyst deactivation by kinetical coke accumulation. Here we present a route to improve ethane conversion using a composite catalyst, involving Zn/HZSM-5 for ethane dehydroaromatization and CaMnO3-δperovskite for in situ selective hydrogen oxidation. The in situ H2 consumption shifts ethane dehydrogenation equilibrium to the desired side and can obviously increase the yield of target product. Furthermore, it is found that the in situ generated H2 O through H2 combustion can significantly suppress the coke formation and consequently enhance the stability of the composite catalyst. After 400 min reaction, a product yield of 23% was retained over the composite catalyst, almost a threefold increase with respect to the Zn/HZSM-5 reference(8%). It is anticipated that this novel composite catalyst combined with an efficient reactor technology may improve the viability of ethane aromatization in utilization.展开更多
Fenton and ozone treatment was investigated at laboratory scale for the degradation of aqueous solutions of nitrobenzene (NB). Effects of reactants concentration (O3, H2O2, and Fe(Ⅱ)), temperature, and pH on NB...Fenton and ozone treatment was investigated at laboratory scale for the degradation of aqueous solutions of nitrobenzene (NB). Effects of reactants concentration (O3, H2O2, and Fe(Ⅱ)), temperature, and pH on NB degradation were monitored. Reaction kinetic of these processes was also assessed. A rapid reaction took place for Fenton process at higher initial concentration of H2O2, higher temperatures, and more acidic conditions (pH 3). Similarly, ozonation reaction exhibited rapid rates for higher ozone dose, higher temperatures, and more basic conditions (pH 11). Complete NB degradation in 65 min was achieved using Fenton process. The conditions of complete elimination of 100 mg/L of initial NB concentration, were 250 mg/L of H202 concentration, pH 3, and 10 mg/L of Fe(Ⅱ) concentration. Under these conditions, 55% organic carbon elimination was achieved. Total organic carbon mineralization was attained in 240 rain reaction time by Fenton process with 900 mg/L of H202 concentration, and 30 mg/L of Fe(Ⅱ) concentration. Fenton reaction showed a pseudo-first order kinetic; the reaction rate constant was ranged from 0.0226 to 0.0658 min^-1. Complete NB degradation was also achieved for an ozone dose of the order of 2.5 g/L. The ozonation was studied at different ozone doses, different initial pH (7-11) and at different temperatures (15-35℃). NB ozonation kinetic was represented by a bi-molecular kinetic model which was reduced to pseudo-first order kinetic. The pseudo-first order reaction rate constant was determined to increase at 20℃ from 0.004 to 0.020 min^-1 as the used ozone increased from 0.4 to 1.9 g/L.展开更多
A simple and efficient method for the iodination of aromatic compounds has been achieved in the presence of iodine and 1,4- bis(triphenylphosphonium)-2-butene peroxodisulfate.
Aromatic nitro compounds were reduced to the corresponding anilines by refluxing with potassium selenated borohydride (KBH2Se3) prepared from potassium borohydride and selenium in refluxed formamide.
A new chromogenic reagent, 1 -(5 - nitro- 3 - benzopsendothiazde)- 3 -(4 - phenylazophenyl) - triazene (NBPTPAPT) has been synthesized and used as a sensitive reagent for the spectrophotometric determination of ...A new chromogenic reagent, 1 -(5 - nitro- 3 - benzopsendothiazde)- 3 -(4 - phenylazophenyl) - triazene (NBPTPAPT) has been synthesized and used as a sensitive reagent for the spectrophotometric determination of cobalt. In the presence of Tween - 80, the reagent with Co ( Ⅱ ) forms a yellow complex (1 : 2) in the buffer solution of Na2B4O7 - NaOH at pH 10.54. The apparent molar absorptivity is 1.220× 10^5 L· mol^- 1· cm^- 1 with the linear range of 0 - 240μg/ L for Co (Ⅱ) by dual-wavelength spectrophotometry. Trace cobalt in vitamin B12 and tea samples has been determined with satisfactory results.展开更多
The equilibrium geometries, energies, harmonic vibrational frequencies, and nucleus independent chemical shifts (NICS) of the new type sandwich structures [As4MAs4]^n- (M = Fe, Co, Ni, Ru, Rh, Pd, Os, Ir and Pt; n ...The equilibrium geometries, energies, harmonic vibrational frequencies, and nucleus independent chemical shifts (NICS) of the new type sandwich structures [As4MAs4]^n- (M = Fe, Co, Ni, Ru, Rh, Pd, Os, Ir and Pt; n = 0, 1 or 2) are investigated at the B3LYP level. All the [As4MAs4]^n- species adopt staggered (D4d) conformations as their stable structures and eclipsed (D4h) conformations as their transition states, and once the sandwich complexes are formed, the As4^2- square properties remain unchanged. The NICS calculation confirms that the complexes of Fe, Co, and Ni are aromatic with negative NICS values, and those of Ru, Rh, and lx exhibit slight aromaticity, while those of Pd, Os, and Pt show slight antiaromaticity.展开更多
Two aromatic multicarboxylate ligands tuned Zn(Ⅱ) coordination polymers, namely, {[Zn0.5(H2L)(tp)0.5(H2O)]H2O}n(1) and {[Zn2(HL)(btc)(H2O)]H2O}n(2)(H2L = 3-(1 Hpyrazol-4-yl)-5-(pyridin-3-yl)-1,2,4-triazole, H2tp = te...Two aromatic multicarboxylate ligands tuned Zn(Ⅱ) coordination polymers, namely, {[Zn0.5(H2L)(tp)0.5(H2O)]H2O}n(1) and {[Zn2(HL)(btc)(H2O)]H2O}n(2)(H2L = 3-(1 Hpyrazol-4-yl)-5-(pyridin-3-yl)-1,2,4-triazole, H2tp = terephthalic acid;H3 btc = 1,3,5-benzenetricarboxylic) have been synthesized. Their structures were characterized by single-crystal X-ray diffraction analysis, elemental analyses and infrared spectra. Compound 1 possesses a one-dimensional chain structure and is finally extended into a three-dimensional supramolecular architecture though hydrogen bonding interactions. Compound 2 shows a three-dimensional framework. Meanwhile, compounds 1 and 2 exhibit luminescent emission in the solid, and can be investigated as potential luminescent materials.展开更多
I.Introduction Nitro-Polycyclic aromatic hydrocarbons(NPAHs)can be formed via the reactions of Polycyclic aromatic hydrocarbons(PAHs)and Nitric oxide(NOx)during the combustion of fossil fuels.Researchers have found th...I.Introduction Nitro-Polycyclic aromatic hydrocarbons(NPAHs)can be formed via the reactions of Polycyclic aromatic hydrocarbons(PAHs)and Nitric oxide(NOx)during the combustion of fossil fuels.Researchers have found that these substances feature carcinogenicity and mutagenicity.展开更多
Room temperature sputtered inorganic nickel oxide(NiO_(x))is one of the most promising hole transport layers(HTL)for perovskite-sillion 2-terminal tandem solar cells with the aid of ultrathin and compact organic layer...Room temperature sputtered inorganic nickel oxide(NiO_(x))is one of the most promising hole transport layers(HTL)for perovskite-sillion 2-terminal tandem solar cells with the aid of ultrathin and compact organic layers to passivate the surface defects.In this study,the aromatic solvent with different substituent groups was used to regulate the conformation of poly[bis(4-phenyl)(2,4,6-trimethylphenyl)am ine](PTAA)layer.As a result,the single-junction perovskite solar cell(PSC)gained a power conversion efficiency(PCE)of 20.63%,contributing to a 27.21%efficiency for monolithic perovskite/silicon(double-side polished)2-terminal tandem solar cell,by applying the alkyl aromatic solvent to enhance theπ-πstacking of PTAA molecular chains.The tandem solar cell can maintain 95%initial efficiency after aging over 1000 h.This study provides a universal approach for improving the photovoltaic performance of NiO_(x)/polymer-based perovskite/silicon tandem solar cells and other single junction inverted PSCs.展开更多
文摘Sulphur-containing aromatic amines were prepared efficiently in good to excellent yields by reduction of the corresponding sulphur-containing aromatic nitro compounds with hydrazine hydrate in the presence of iron(Ⅲ) oxide-MgO catalyst. The catalyst exhibited high activity and stability for the reduction of sulphur-containing aromatic nitro compounds. The yields of sulphur-containing aromatic amines were up to 91-99 % at 355 K after reduction for 1-4 h over this catalyst.
文摘Sulphur-containing aromatic nitro compounds were rapidly reduced to the corresponding amines in high yields by employing hydrazine hydrate as a hydrogen donor in the presence of iron oxide hydroxide catalyst. It was worth noting that the catalyst exhibited extremely high activity. The reduction could be completed within 20-50 min and the yields were up to 97-99 %.
基金Financial support from the National Natural Science Foundation of China (grant 21606249, 21536005)the Director Innovation Fund of Key Laboratory of Biofuels, Chinese Academy of Sciences (grant Y57201190V)QIBEBT and Dalian National Laboratory For Clean Energy (DNL), CAS (Grant QIBEBT I201924)。
文摘Ethane conversion to ethylene and aromatics over Zn/zeolite catalysts is a promising technology for efficient exploitation of light alkanes. However, the reaction faces two major hurdles including the limited ethane conversion due to thermodynamics and the drastic catalyst deactivation by kinetical coke accumulation. Here we present a route to improve ethane conversion using a composite catalyst, involving Zn/HZSM-5 for ethane dehydroaromatization and CaMnO3-δperovskite for in situ selective hydrogen oxidation. The in situ H2 consumption shifts ethane dehydrogenation equilibrium to the desired side and can obviously increase the yield of target product. Furthermore, it is found that the in situ generated H2 O through H2 combustion can significantly suppress the coke formation and consequently enhance the stability of the composite catalyst. After 400 min reaction, a product yield of 23% was retained over the composite catalyst, almost a threefold increase with respect to the Zn/HZSM-5 reference(8%). It is anticipated that this novel composite catalyst combined with an efficient reactor technology may improve the viability of ethane aromatization in utilization.
文摘Fenton and ozone treatment was investigated at laboratory scale for the degradation of aqueous solutions of nitrobenzene (NB). Effects of reactants concentration (O3, H2O2, and Fe(Ⅱ)), temperature, and pH on NB degradation were monitored. Reaction kinetic of these processes was also assessed. A rapid reaction took place for Fenton process at higher initial concentration of H2O2, higher temperatures, and more acidic conditions (pH 3). Similarly, ozonation reaction exhibited rapid rates for higher ozone dose, higher temperatures, and more basic conditions (pH 11). Complete NB degradation in 65 min was achieved using Fenton process. The conditions of complete elimination of 100 mg/L of initial NB concentration, were 250 mg/L of H202 concentration, pH 3, and 10 mg/L of Fe(Ⅱ) concentration. Under these conditions, 55% organic carbon elimination was achieved. Total organic carbon mineralization was attained in 240 rain reaction time by Fenton process with 900 mg/L of H202 concentration, and 30 mg/L of Fe(Ⅱ) concentration. Fenton reaction showed a pseudo-first order kinetic; the reaction rate constant was ranged from 0.0226 to 0.0658 min^-1. Complete NB degradation was also achieved for an ozone dose of the order of 2.5 g/L. The ozonation was studied at different ozone doses, different initial pH (7-11) and at different temperatures (15-35℃). NB ozonation kinetic was represented by a bi-molecular kinetic model which was reduced to pseudo-first order kinetic. The pseudo-first order reaction rate constant was determined to increase at 20℃ from 0.004 to 0.020 min^-1 as the used ozone increased from 0.4 to 1.9 g/L.
文摘A simple and efficient method for the iodination of aromatic compounds has been achieved in the presence of iodine and 1,4- bis(triphenylphosphonium)-2-butene peroxodisulfate.
文摘Aromatic nitro compounds were reduced to the corresponding anilines by refluxing with potassium selenated borohydride (KBH2Se3) prepared from potassium borohydride and selenium in refluxed formamide.
基金Natural Science Foundation of Fujian Province (No.D0410027)
文摘A new chromogenic reagent, 1 -(5 - nitro- 3 - benzopsendothiazde)- 3 -(4 - phenylazophenyl) - triazene (NBPTPAPT) has been synthesized and used as a sensitive reagent for the spectrophotometric determination of cobalt. In the presence of Tween - 80, the reagent with Co ( Ⅱ ) forms a yellow complex (1 : 2) in the buffer solution of Na2B4O7 - NaOH at pH 10.54. The apparent molar absorptivity is 1.220× 10^5 L· mol^- 1· cm^- 1 with the linear range of 0 - 240μg/ L for Co (Ⅱ) by dual-wavelength spectrophotometry. Trace cobalt in vitamin B12 and tea samples has been determined with satisfactory results.
文摘The equilibrium geometries, energies, harmonic vibrational frequencies, and nucleus independent chemical shifts (NICS) of the new type sandwich structures [As4MAs4]^n- (M = Fe, Co, Ni, Ru, Rh, Pd, Os, Ir and Pt; n = 0, 1 or 2) are investigated at the B3LYP level. All the [As4MAs4]^n- species adopt staggered (D4d) conformations as their stable structures and eclipsed (D4h) conformations as their transition states, and once the sandwich complexes are formed, the As4^2- square properties remain unchanged. The NICS calculation confirms that the complexes of Fe, Co, and Ni are aromatic with negative NICS values, and those of Ru, Rh, and lx exhibit slight aromaticity, while those of Pd, Os, and Pt show slight antiaromaticity.
基金financially supported by the National Natural Science Foundation of China(21571093)
文摘Two aromatic multicarboxylate ligands tuned Zn(Ⅱ) coordination polymers, namely, {[Zn0.5(H2L)(tp)0.5(H2O)]H2O}n(1) and {[Zn2(HL)(btc)(H2O)]H2O}n(2)(H2L = 3-(1 Hpyrazol-4-yl)-5-(pyridin-3-yl)-1,2,4-triazole, H2tp = terephthalic acid;H3 btc = 1,3,5-benzenetricarboxylic) have been synthesized. Their structures were characterized by single-crystal X-ray diffraction analysis, elemental analyses and infrared spectra. Compound 1 possesses a one-dimensional chain structure and is finally extended into a three-dimensional supramolecular architecture though hydrogen bonding interactions. Compound 2 shows a three-dimensional framework. Meanwhile, compounds 1 and 2 exhibit luminescent emission in the solid, and can be investigated as potential luminescent materials.
文摘I.Introduction Nitro-Polycyclic aromatic hydrocarbons(NPAHs)can be formed via the reactions of Polycyclic aromatic hydrocarbons(PAHs)and Nitric oxide(NOx)during the combustion of fossil fuels.Researchers have found that these substances feature carcinogenicity and mutagenicity.
基金supported by the National Key R&D Program of China(2018YFB1500103)the National Natural Science Foundation of China(62104082)+1 种基金the Guangdong Basic and Applied Basic Research Foundation(2022A1515010746,2022A1515011228)the Science and Technology Program of Guangzhou(202201010458)。
文摘Room temperature sputtered inorganic nickel oxide(NiO_(x))is one of the most promising hole transport layers(HTL)for perovskite-sillion 2-terminal tandem solar cells with the aid of ultrathin and compact organic layers to passivate the surface defects.In this study,the aromatic solvent with different substituent groups was used to regulate the conformation of poly[bis(4-phenyl)(2,4,6-trimethylphenyl)am ine](PTAA)layer.As a result,the single-junction perovskite solar cell(PSC)gained a power conversion efficiency(PCE)of 20.63%,contributing to a 27.21%efficiency for monolithic perovskite/silicon(double-side polished)2-terminal tandem solar cell,by applying the alkyl aromatic solvent to enhance theπ-πstacking of PTAA molecular chains.The tandem solar cell can maintain 95%initial efficiency after aging over 1000 h.This study provides a universal approach for improving the photovoltaic performance of NiO_(x)/polymer-based perovskite/silicon tandem solar cells and other single junction inverted PSCs.