Agropyron cristatum(2n=4x=28,PPPP),which harbours many high-yield and disease-resistance genes,is a promising donor for wheat improvement.Narrow genetic diversity and the trade-off between grain weight and grain numbe...Agropyron cristatum(2n=4x=28,PPPP),which harbours many high-yield and disease-resistance genes,is a promising donor for wheat improvement.Narrow genetic diversity and the trade-off between grain weight and grain number have become bottlenecks for increasing grain yield in wheat.In this study,a novel translocation line,WAT650l,was derived from the chromosome 6P addition line 4844–12,which can simultaneously increase both grain number per spike(GNS)and thousand-grain weight(TGW).Cytological analysis and molecular marker analysis revealed that WAT650l was a 5BL.5BS-6PL(bin 12–17)translocation line.Assessment of agronomic traits and analysis of the BC4F2 and BC5F2 populations suggested that the 6PL terminal chromosome segment in WAT650l resulted in increased grain number per spike(average increased by 14.07 grains),thousand-grain weight(average increased by 4.31 g),flag leaf length,plant height,spikelet number per spike and kernel number per spikelet during the two growing seasons of 2020–2021 and 2021–2022.Additionally,the increased GNS locus and high-TGW locus of WAT650l were mapped to the bins 16–17 and 12–13,respectively,on chromosome 6PL by genetic population analysis of three translocation lines.In summary,we provide a valuable germplasm resource for broadening the genetic base of wheat and overcoming the negative relationship between GNS and TGW in wheat breeding.展开更多
Wide hybridization is a strategy for broadening the genetic basis of wheat. Because an efficient method for inducing wheat–alien chromosome translocations will allow producing useful germplasm, it is desirable to dis...Wide hybridization is a strategy for broadening the genetic basis of wheat. Because an efficient method for inducing wheat–alien chromosome translocations will allow producing useful germplasm, it is desirable to discover new genes that induce chromosomal variation. In this study, chromosome 5P from A.cristatum was shown to induce many types of chromosomal structural variation in a common wheat background, including nonhomoeologous chromosome translocations, as revealed by genomic in situ hybridization, fluorescence in situ hybridization, and DNA marker analysis. Aberrant meiosis was associated with chromosomal structural variation, and aberrant meiotic behavior was observed in wheat–A.cristatum 5P monosomic and disomic addition lines, suggesting that the effect of chromosome 5P was independent of the number of chromosome 5P copies. Chromosome 5P disturbed homologous chromosome pairing at pachytene stage in a common wheat background, resulting in a high frequency of univalent formation and reduced crossing over. Thirteen genes involved in DNA repair or chromatin remodeling, including RAD52-like and MSH6 genes, were differentially expressed(upregulated) in wheat–A. cristatum 5P addition lines according to transcriptome analysis, implicating chromosome 5P in the process of meiotic double-strand break repair. These findings provide a new, efficient tool for inducing wheat–alien chromosome translocations and producing new germplasm.展开更多
As an important wild relative of wheat, Agropyron cristatum has been successfully used for wheat improvement. Currently, a few useful agronomic traits of A. cristatum, such as high grain number per spike and resistanc...As an important wild relative of wheat, Agropyron cristatum has been successfully used for wheat improvement. Currently, a few useful agronomic traits of A. cristatum, such as high grain number per spike and resistance to diseases, have been transferred into common wheat.However, the effective detection of small A. cristatum segmental introgressions in common wheat is still difficult. The objective of this study was to identify A. cristatum-specific single nucleotide polymorphisms(SNPs) for the detection of small alien segments in wheat. The transcriptome sequences of A. cristatum were aligned against wheat coding DNA sequences(CDS) for SNP calling. As a result, we discovered a total of 167,613 putative SNPs specific to the P genome of A. cristatum compared with the common wheat genomes. Among 230 selected SNPs with functional annotations related to inflorescence development and stress resistance,68 were validated as P genome-specific SNPs in multiple wheat backgrounds using Kompetitive Allele Specific PCR(KASP) assays. Among them, 55 SNPs were assigned to six homoeologous groups of the P genome using wheat-A. cristatum addition lines, and 6 P-specific SNP markers were further physically mapped on different segments of chromosome 6 P in 6 P translocation lines. The P genome-specific SNPs were also validated by Sanger sequencing and used to detect the P chromatin in wheat-A. cristatum cryptic introgression lines. Two SNP markers(Unigene20217-182 and Unigene20307-1420) were detected in two wheat-A. cristatum introgression lines that showed enhanced grain number per spike and high resistance to powdery mildew. Together, the developed P genome-specific SNP markers will accelerate the detection of large numbers of wheat-A. cristatum derivatives and will be helpful for marker-assisted transfer of desirable traits from A. cristatum into adapted wheat cultivars in wheat breeding programs.展开更多
Soils with spatial variability are the product of natural history.The mechanical properties tested by soil samples from boreholes in the same soil layer may be different.Underground structure service in surrounding so...Soils with spatial variability are the product of natural history.The mechanical properties tested by soil samples from boreholes in the same soil layer may be different.Underground structure service in surrounding soils,their seismic response is controlled by the deformation of the surrounding soils.The variability of soil mechanical parameters was not considered in the current research on the seismic response of underground structures.Therefore,a random field model was established to describe the spatial variability of surrounding soils based on the random field theory.Then the seismic response of underground structures in the random field was simulated based on the time-domain explicit global FEM analysis,and the soil mechanical parameters and earthquake intensity influencing the seismic response of surrounding soils and underground structures were studied.Numerical results presented that,the randomness of soil parameters does not change the plastic deformation mode of surrounding soils significantly.The variation coefficients of inter-story deformation of structures and lateral deformation of columns are much smaller than that of mechanical parameters,and the randomness of soil parameters has no obvious effect on the structural deformation response.展开更多
Silicon(Si)-based solid-state batteries(Si-SSBs)are attracting tremendous attention because of their high energy density and unprecedented safety,making them become promising candidates for next-generation energy stor...Silicon(Si)-based solid-state batteries(Si-SSBs)are attracting tremendous attention because of their high energy density and unprecedented safety,making them become promising candidates for next-generation energy storage systems.Nevertheless,the commercialization of Si-SSBs is significantly impeded by enormous challenges including large volume variation,severe interfacial problems,elusive fundamental mechanisms,and unsatisfied electrochemical performance.Besides,some unknown electrochemical processes in Si-based anode,solid-state electrolytes(SSEs),and Si-based anode/SSE interfaces are still needed to be explored,while an in-depth understanding of solid–solid interfacial chemistry is insufficient in Si-SSBs.This review aims to summarize the current scientific and technological advances and insights into tackling challenges to promote the deployment of Si-SSBs.First,the differences between various conventional liquid electrolyte-dominated Si-based lithium-ion batteries(LIBs)with Si-SSBs are discussed.Subsequently,the interfacial mechanical contact model,chemical reaction properties,and charge transfer kinetics(mechanical–chemical kinetics)between Si-based anode and three different SSEs(inorganic(oxides)SSEs,organic–inorganic composite SSEs,and inorganic(sulfides)SSEs)are systemically reviewed,respectively.Moreover,the progress for promising inorganic(sulfides)SSE-based Si-SSBs on the aspects of electrode constitution,three-dimensional structured electrodes,and external stack pressure is highlighted,respectively.Finally,future research directions and prospects in the development of Si-SSBs are proposed.展开更多
Barley is a diploid species with a genome smaller than those of other members of the Triticeae tribe,making it an attractive model for genetic studies in Triticeae crops.The recent development of barley genomics has c...Barley is a diploid species with a genome smaller than those of other members of the Triticeae tribe,making it an attractive model for genetic studies in Triticeae crops.The recent development of barley genomics has created a need for a high-throughput platform to identify genetically uniform mutants for gene function investigations.In this study,we report an ethyl methanesulfonate(EMS)-mutagenized population consisting of 8525M_(3) lines in the barley landrace“Hatiexi”(HTX),which we complement with a high-quality de novo assembly of a reference genome for this genotype.The mutation rate within the population ranged from 1.51 to 4.09 mutations per megabase,depending on the treatment dosage of EMS and the mutation discrimination platform used for genotype analysis.We implemented a three-dimensional DNA pooling strategy combined with multiplexed amplicon sequencing to create a highly efficient and cost-effective TILLING(targeting induced locus lesion in genomes)platform in barley.Mutations were successfully identified from 72 mixed amplicons within a DNA pool containing 64 individual mutants and from 56 mixed amplicons within a pool containing 144 individuals.We discovered abundant allelic mutants for dozens of genes,including the barley Green Revolution contributor gene Brassinosteroid insensitive 1(BRI1).As a proof of concept,we rapidly determined the causal gene responsible for a chlorotic mutant by following the MutMap strategy,demonstrating the value of this resource to support forward and reverse genetic studies in barley.展开更多
Bread wheat （Triticum aestivum, AABBDD） is an allohexaploid species derived from two rounds of interspecific hybridizations. A high-quality genome sequence assembly of diploid Aegilops tauschii, the donor of the whe...Bread wheat （Triticum aestivum, AABBDD） is an allohexaploid species derived from two rounds of interspecific hybridizations. A high-quality genome sequence assembly of diploid Aegilops tauschii, the donor of the wheat D genome, will provide a useful platform to study polyploid wheat evolution. A combined approach of BAC pooling and next-generation sequencing technology was employed to sequence the minimum tiling path （MTP） of 3176 BAC clones from the short arm ofAe. tauschii chromosome 3 （At3DS）. The final assembly of 135 super-scaffolds with an N50 of 4.2 Mb was used to build a 247-Mb pseudomolecule with a total of 2222 predicted protein-coding genes. Compared with the orthologous regions of rice, Brachypodium, and sorghum, At3DS contains 38.67% more genes. In comparison to At3DS, the short arm sequence of wheat chromosome 3B （Ta3BS） is 95-Mb large in size, which is primarily due to the expansion of the non-centromeric region, suggesting that transposable element （TE） bursts in Ta3B likely occurred there. Also, the size increase is accompanied by a proportional increase in gene number in Ta3BS. We found that in the sequence of short arm of wheat chromosome 3D （Ta3DS）, there was only less than 0.27% gene loss compared to At3DS. Our study reveals divergent evolution of grass genomes and provides new insights into sequence changes in the polyploid wheat genome.展开更多
Novel organic-inorganic hybrids were synthesized by using HfCl 4 and organic ligand 1H-pyrrole-2,5-dicarboxylic acid(PDCA)via a simple hydrothermal method.The as-prepared Hf-PDCA were characterized by various techniqu...Novel organic-inorganic hybrids were synthesized by using HfCl 4 and organic ligand 1H-pyrrole-2,5-dicarboxylic acid(PDCA)via a simple hydrothermal method.The as-prepared Hf-PDCA were characterized by various techniques,such as electron microscope,N_(2) adsorption/desorption,and X-ray photoelectron spectroscopy.Among them,the porous and nitrogen-containing Hf-PDCA as heterogeneous acid/base bifunctional catalyst was then applied to the catalytic hydrogenation of furfural to produce furfuryl alcohol(FFA).It exhibited excellent catalytic performance,with high conversion(98.8%)and selectivity(98.5%)by using 2-propanol as hydrogen source under a relatively mild condition.Moreover,the Hf-PDCA has strong stability and durability,and can be recovered after the catalyst reaction.In addition,the Hf-PDCA as catalyst can be extended to fabricate corresponding alcohols by catalytic conversion of other biomass derived aldehydes.展开更多
Metal salts with highly electronegative cations have been used to effectively catalyze the liquid-phase nitration of benzene by NO2 to nitrobenzene under solventfree conditions. Several salts including FeCl3, ZrCl4, A...Metal salts with highly electronegative cations have been used to effectively catalyze the liquid-phase nitration of benzene by NO2 to nitrobenzene under solventfree conditions. Several salts including FeCl3, ZrCl4, AlCl3, CuCl2, NiCl2, ZnCl2, MnCl2, Fe（NO3）3-9H2O, Bi （NO3）3·5H2O, Zr（NO3）4-SH2O, Cu（NO3）2.6H2O, Ni （NO3）2·6H2O, Zn（NO3）2·6H2O, Fe2（SO4）3, and CuSO4 were examined and anhydrous FeCl3 exhibited the best catalytic performance under the optimal reaction conditions. The benzene conversion and selectivity to nitrobenzene were both over 99%. In addition, it was determined that the metal counterion and the presence of water hydrates in the salt affects the catalytic activity. This method is simple and efficient and may have potential industrial application prospects.展开更多
基金financially supported by the National Natural Science Foundation of China(32171961)the Agricultural Science and Technology Innovation Program of CAAS(CAASASTIP-2021-ICS)。
文摘Agropyron cristatum(2n=4x=28,PPPP),which harbours many high-yield and disease-resistance genes,is a promising donor for wheat improvement.Narrow genetic diversity and the trade-off between grain weight and grain number have become bottlenecks for increasing grain yield in wheat.In this study,a novel translocation line,WAT650l,was derived from the chromosome 6P addition line 4844–12,which can simultaneously increase both grain number per spike(GNS)and thousand-grain weight(TGW).Cytological analysis and molecular marker analysis revealed that WAT650l was a 5BL.5BS-6PL(bin 12–17)translocation line.Assessment of agronomic traits and analysis of the BC4F2 and BC5F2 populations suggested that the 6PL terminal chromosome segment in WAT650l resulted in increased grain number per spike(average increased by 14.07 grains),thousand-grain weight(average increased by 4.31 g),flag leaf length,plant height,spikelet number per spike and kernel number per spikelet during the two growing seasons of 2020–2021 and 2021–2022.Additionally,the increased GNS locus and high-TGW locus of WAT650l were mapped to the bins 16–17 and 12–13,respectively,on chromosome 6PL by genetic population analysis of three translocation lines.In summary,we provide a valuable germplasm resource for broadening the genetic base of wheat and overcoming the negative relationship between GNS and TGW in wheat breeding.
基金financially supported by the National Key Research and Development Program of China (2021YFD1200605)the National Natural Science Foundation of China (32171961)。
文摘Wide hybridization is a strategy for broadening the genetic basis of wheat. Because an efficient method for inducing wheat–alien chromosome translocations will allow producing useful germplasm, it is desirable to discover new genes that induce chromosomal variation. In this study, chromosome 5P from A.cristatum was shown to induce many types of chromosomal structural variation in a common wheat background, including nonhomoeologous chromosome translocations, as revealed by genomic in situ hybridization, fluorescence in situ hybridization, and DNA marker analysis. Aberrant meiosis was associated with chromosomal structural variation, and aberrant meiotic behavior was observed in wheat–A.cristatum 5P monosomic and disomic addition lines, suggesting that the effect of chromosome 5P was independent of the number of chromosome 5P copies. Chromosome 5P disturbed homologous chromosome pairing at pachytene stage in a common wheat background, resulting in a high frequency of univalent formation and reduced crossing over. Thirteen genes involved in DNA repair or chromatin remodeling, including RAD52-like and MSH6 genes, were differentially expressed(upregulated) in wheat–A. cristatum 5P addition lines according to transcriptome analysis, implicating chromosome 5P in the process of meiotic double-strand break repair. These findings provide a new, efficient tool for inducing wheat–alien chromosome translocations and producing new germplasm.
基金supported by the China Agriculture Research System(CARS-03)the National Key Research and Development Program of China(2016YFD0102000)
文摘As an important wild relative of wheat, Agropyron cristatum has been successfully used for wheat improvement. Currently, a few useful agronomic traits of A. cristatum, such as high grain number per spike and resistance to diseases, have been transferred into common wheat.However, the effective detection of small A. cristatum segmental introgressions in common wheat is still difficult. The objective of this study was to identify A. cristatum-specific single nucleotide polymorphisms(SNPs) for the detection of small alien segments in wheat. The transcriptome sequences of A. cristatum were aligned against wheat coding DNA sequences(CDS) for SNP calling. As a result, we discovered a total of 167,613 putative SNPs specific to the P genome of A. cristatum compared with the common wheat genomes. Among 230 selected SNPs with functional annotations related to inflorescence development and stress resistance,68 were validated as P genome-specific SNPs in multiple wheat backgrounds using Kompetitive Allele Specific PCR(KASP) assays. Among them, 55 SNPs were assigned to six homoeologous groups of the P genome using wheat-A. cristatum addition lines, and 6 P-specific SNP markers were further physically mapped on different segments of chromosome 6 P in 6 P translocation lines. The P genome-specific SNPs were also validated by Sanger sequencing and used to detect the P chromatin in wheat-A. cristatum cryptic introgression lines. Two SNP markers(Unigene20217-182 and Unigene20307-1420) were detected in two wheat-A. cristatum introgression lines that showed enhanced grain number per spike and high resistance to powdery mildew. Together, the developed P genome-specific SNP markers will accelerate the detection of large numbers of wheat-A. cristatum derivatives and will be helpful for marker-assisted transfer of desirable traits from A. cristatum into adapted wheat cultivars in wheat breeding programs.
基金supported by the Beijing Natural Science Foundation(8212007)the Pyramid Talent Training Project of Beijing University of Civil Engineering and Architecture(JDYC20200311)。
文摘Soils with spatial variability are the product of natural history.The mechanical properties tested by soil samples from boreholes in the same soil layer may be different.Underground structure service in surrounding soils,their seismic response is controlled by the deformation of the surrounding soils.The variability of soil mechanical parameters was not considered in the current research on the seismic response of underground structures.Therefore,a random field model was established to describe the spatial variability of surrounding soils based on the random field theory.Then the seismic response of underground structures in the random field was simulated based on the time-domain explicit global FEM analysis,and the soil mechanical parameters and earthquake intensity influencing the seismic response of surrounding soils and underground structures were studied.Numerical results presented that,the randomness of soil parameters does not change the plastic deformation mode of surrounding soils significantly.The variation coefficients of inter-story deformation of structures and lateral deformation of columns are much smaller than that of mechanical parameters,and the randomness of soil parameters has no obvious effect on the structural deformation response.
基金supported by the National Natural Science Foundation of China(Grants Nos.52072323,52122211 and 21875155)the State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources(Grant No.LAPS22005)+3 种基金the Frontier Exploration Projects of Longmen Laboratory(Grant No.LMQYTSKT008)the Shenzhen Technical Plan Project(No.JCYJ20220818101003008)the support of High-Tech Industrialization Project of Tan Kah Kee Innovation Laboratory(Grant No.RD2021010101)the“Double-First Class”Foundation of Materials and Intelligent Manufacturing Discipline of Xiamen University.L.Zhang and Q.Zhang acknowledge the support of the Nanqiang Young Top-notch Talent Fellowship at Xiamen University.
文摘Silicon(Si)-based solid-state batteries(Si-SSBs)are attracting tremendous attention because of their high energy density and unprecedented safety,making them become promising candidates for next-generation energy storage systems.Nevertheless,the commercialization of Si-SSBs is significantly impeded by enormous challenges including large volume variation,severe interfacial problems,elusive fundamental mechanisms,and unsatisfied electrochemical performance.Besides,some unknown electrochemical processes in Si-based anode,solid-state electrolytes(SSEs),and Si-based anode/SSE interfaces are still needed to be explored,while an in-depth understanding of solid–solid interfacial chemistry is insufficient in Si-SSBs.This review aims to summarize the current scientific and technological advances and insights into tackling challenges to promote the deployment of Si-SSBs.First,the differences between various conventional liquid electrolyte-dominated Si-based lithium-ion batteries(LIBs)with Si-SSBs are discussed.Subsequently,the interfacial mechanical contact model,chemical reaction properties,and charge transfer kinetics(mechanical–chemical kinetics)between Si-based anode and three different SSEs(inorganic(oxides)SSEs,organic–inorganic composite SSEs,and inorganic(sulfides)SSEs)are systemically reviewed,respectively.Moreover,the progress for promising inorganic(sulfides)SSE-based Si-SSBs on the aspects of electrode constitution,three-dimensional structured electrodes,and external stack pressure is highlighted,respectively.Finally,future research directions and prospects in the development of Si-SSBs are proposed.
基金funded by grants from the National Key Research and Development Program of China(2018YFD1000702/2018YFD1000700)the Agricultural Science and Technology Innovation Program of the Chinese Academy of Agricultural Sciences(CAAS),China.
文摘Barley is a diploid species with a genome smaller than those of other members of the Triticeae tribe,making it an attractive model for genetic studies in Triticeae crops.The recent development of barley genomics has created a need for a high-throughput platform to identify genetically uniform mutants for gene function investigations.In this study,we report an ethyl methanesulfonate(EMS)-mutagenized population consisting of 8525M_(3) lines in the barley landrace“Hatiexi”(HTX),which we complement with a high-quality de novo assembly of a reference genome for this genotype.The mutation rate within the population ranged from 1.51 to 4.09 mutations per megabase,depending on the treatment dosage of EMS and the mutation discrimination platform used for genotype analysis.We implemented a three-dimensional DNA pooling strategy combined with multiplexed amplicon sequencing to create a highly efficient and cost-effective TILLING(targeting induced locus lesion in genomes)platform in barley.Mutations were successfully identified from 72 mixed amplicons within a DNA pool containing 64 individual mutants and from 56 mixed amplicons within a pool containing 144 individuals.We discovered abundant allelic mutants for dozens of genes,including the barley Green Revolution contributor gene Brassinosteroid insensitive 1(BRI1).As a proof of concept,we rapidly determined the causal gene responsible for a chlorotic mutant by following the MutMap strategy,demonstrating the value of this resource to support forward and reverse genetic studies in barley.
基金supported by funding from the National Natural Science Foundation of China(Nos.31290210,31210103902)the Unites States National Science Foundation grant(No.IOS 1238231)+1 种基金the USDA-Agricultural Research Service CRIS project(No.5325-21000-019)the Ministry of Education of China(111 project)
文摘Bread wheat （Triticum aestivum, AABBDD） is an allohexaploid species derived from two rounds of interspecific hybridizations. A high-quality genome sequence assembly of diploid Aegilops tauschii, the donor of the wheat D genome, will provide a useful platform to study polyploid wheat evolution. A combined approach of BAC pooling and next-generation sequencing technology was employed to sequence the minimum tiling path （MTP） of 3176 BAC clones from the short arm ofAe. tauschii chromosome 3 （At3DS）. The final assembly of 135 super-scaffolds with an N50 of 4.2 Mb was used to build a 247-Mb pseudomolecule with a total of 2222 predicted protein-coding genes. Compared with the orthologous regions of rice, Brachypodium, and sorghum, At3DS contains 38.67% more genes. In comparison to At3DS, the short arm sequence of wheat chromosome 3B （Ta3BS） is 95-Mb large in size, which is primarily due to the expansion of the non-centromeric region, suggesting that transposable element （TE） bursts in Ta3B likely occurred there. Also, the size increase is accompanied by a proportional increase in gene number in Ta3BS. We found that in the sequence of short arm of wheat chromosome 3D （Ta3DS）, there was only less than 0.27% gene loss compared to At3DS. Our study reveals divergent evolution of grass genomes and provides new insights into sequence changes in the polyploid wheat genome.
基金support for this work by National Natural Science Foundation of China(No.21774036,No.21805047)Guangdong Province Science Foundation(No.2017GC010429).
文摘Novel organic-inorganic hybrids were synthesized by using HfCl 4 and organic ligand 1H-pyrrole-2,5-dicarboxylic acid(PDCA)via a simple hydrothermal method.The as-prepared Hf-PDCA were characterized by various techniques,such as electron microscope,N_(2) adsorption/desorption,and X-ray photoelectron spectroscopy.Among them,the porous and nitrogen-containing Hf-PDCA as heterogeneous acid/base bifunctional catalyst was then applied to the catalytic hydrogenation of furfural to produce furfuryl alcohol(FFA).It exhibited excellent catalytic performance,with high conversion(98.8%)and selectivity(98.5%)by using 2-propanol as hydrogen source under a relatively mild condition.Moreover,the Hf-PDCA has strong stability and durability,and can be recovered after the catalyst reaction.In addition,the Hf-PDCA as catalyst can be extended to fabricate corresponding alcohols by catalytic conversion of other biomass derived aldehydes.
基金We gratefully acknowledge the financial support for this work by the National Natural Science Foundation of China （Grant Nos. 21676226 and 21306158）, the Collaborative Innovation Center of New Chemical Technologies for Environmental Benignity and Efficient Resource Utilization, and the Project of Technological Innovation ＆ Entrepreneurship Platform for Hunan Youth （2014）.
文摘Metal salts with highly electronegative cations have been used to effectively catalyze the liquid-phase nitration of benzene by NO2 to nitrobenzene under solventfree conditions. Several salts including FeCl3, ZrCl4, AlCl3, CuCl2, NiCl2, ZnCl2, MnCl2, Fe（NO3）3-9H2O, Bi （NO3）3·5H2O, Zr（NO3）4-SH2O, Cu（NO3）2.6H2O, Ni （NO3）2·6H2O, Zn（NO3）2·6H2O, Fe2（SO4）3, and CuSO4 were examined and anhydrous FeCl3 exhibited the best catalytic performance under the optimal reaction conditions. The benzene conversion and selectivity to nitrobenzene were both over 99%. In addition, it was determined that the metal counterion and the presence of water hydrates in the salt affects the catalytic activity. This method is simple and efficient and may have potential industrial application prospects.
