Vanadium nitrides were prepared via one step method of carbothermal reduction and nitridation of vanadium trioxide. Thermalgravimetric analysis （TGA） and X-ray diffraction were used to determine the reaction paths o...Vanadium nitrides were prepared via one step method of carbothermal reduction and nitridation of vanadium trioxide. Thermalgravimetric analysis （TGA） and X-ray diffraction were used to determine the reaction paths of vanadium carbide, namely the following sequential reaction： V2O3→V8C7 in higher temperature stage, the rule of vanadium nitride synthesized was established, and defined conditions of temperature for the production of the carbides and nitrides were determined. Vanadium oxycarbide may consist in the front process of carbothermal reduction of vanadium trioxide. In one step method for vanadium nitride by carbothermal reduction and nitridation of vanadium trioxide, the nitridation process is simultaneous with the carbothermal reduction. A one-step mechanism of the carbothermal reduction with simultaneous nitridation leaded to a lower terminal temperature in nitridation process for vanadium nitride produced, compared with that of carbothermal reduction process without nitridation. The grain size and shape of vanadium nitride were uniform, and had the shape of a cube. The one step method combined vacuum carborization and nitridation （namely two step method） into one process. It simplified the technological process and decreased the costs.展开更多
[Objective] The aim of this study was to extract RNA,DNA and protein from plants by using modified one step method.[Method]CTAB was used for the modifying of Biozol-based one step extraction method,which was then used...[Objective] The aim of this study was to extract RNA,DNA and protein from plants by using modified one step method.[Method]CTAB was used for the modifying of Biozol-based one step extraction method,which was then used for the isolation of RNA,DNA and protein from the roots of maize（Zea mays L.）,soybean（Glycine max L.）,alfalfa（Medicago sativa L.）and cucumber（Cucumis sativus L.）.And the heme oxygenase-1 gene（HO-1）and calcium-dependent protein kinase-1 gene（CDPK1）,as well as HO-1 protein were identified.[Result]The result of UV spectrophotometer determination and agarose gel electrophoresis analysis showed that the purity of obtained RNA and DNA sample was relatively high;HO-1 and CDPK1 gene exhibited the positive signals checked by RT-PCR;the extracted protein could be used for western blotting analysis;the whole isolation procedure cost 3 h.[Conclusion]This method can be used as a good reference for researcher and will offer a better value with a wide range of applications.展开更多
A membrane element model with bending modification based on element moment equilibrium is proposed for the first time by the authors, who apply the element model in one step inverse method and simulate the forming pro...A membrane element model with bending modification based on element moment equilibrium is proposed for the first time by the authors, who apply the element model in one step inverse method and simulate the forming process of a flower-shaped box using the membrane element model with and without this modification. The numerical results are compared with those of the incremental method to verify the validity of the element model developed in this paper.展开更多
Graphitic carbon nitride(g-C_(3)N_(4))-based materials are regarded as one of the most potential photocatalysts for utilizing solar energy.In this work,we reported a facile one step in-situ hydrothermal-roasting metho...Graphitic carbon nitride(g-C_(3)N_(4))-based materials are regarded as one of the most potential photocatalysts for utilizing solar energy.In this work,we reported a facile one step in-situ hydrothermal-roasting method for preparing honeycomb-like g-C_(3)N_(4)/CeO_(2) nanosheets with abundant oxygen vacancies(g-C_(3)N_(4)/CeO_(2)-x).The hydrothermal-roasting and incomplete-sealed state can(i)generate an in-situ reducing atmosphere(CO,N2,NH3) to tune the concentration of oxygen vacancies in CeO_(2);(ii) beneficial to prevent continuous growth of g-C_(3)N_(4) and results in honeycomb-like g-C_(3)N_(4)/CeO_(2)-x hybrid nanosheets.What is more,the g-C_(3)N_(4)/CeO_(2)-x photocatalyst exhibited extended photoresponse range,increased specific surface area and obviously enhanced separation efficiency of photogenerated electron-hole pairs.As a proof-of-concept application,the optimized g-C_(3)N_(4)/CeO_(2)-xnanosheets could achieve 98% removal efficiency for Cr(Ⅵ) under visible light irradiation(λ≥420 nm)within 2.5 h,which is significantly better than those of pure g-C_(3)N_(4) and CeO_(2).This work provides a new idea for more rationally designing and constructing g-C_(3)N_(4)-based catalysts for efficient extended photochemical application.展开更多
Organic-inorganic lead halide perovskites represent a group of materials with diverse structures and promising optical/optoelectronic properties.The performance of perovskite based solar cells relies tremendously on t...Organic-inorganic lead halide perovskites represent a group of materials with diverse structures and promising optical/optoelectronic properties.The performance of perovskite based solar cells relies tremendously on the structure/properties of the absorber.The physicochemical properties of the perovskite active layer depend on the substrate,preparation methods,environments and the starting materials.In this study,we investigated the effects of starting materials in the precursor solution on the physicochemical properties of the resulting one-step spin coated MA_(0.8)FA_(0.2)PbI_(3-y)Br_(y) film and the photovoltaic performance of the corresponding inverted(p-i-n)perovskite solar cells.Two precursor solutions containing exactly the same atom stoichiometry were prepared from two different groups of starting materials(Group A:CH_(3)NH_(3)I,CH(NH_(2))_(2)I,CH_(3)NH_(3)Br,and PbI_(2);Group B:CH_(3)NH_(3)I,CH(NH_(2))_(2)I,PbI_(2) and PbBr_(2)).The MA_(0.8)FA_(0.2)PbI_(3-y)Br_(y) films(A1 and A2)prepared from the A precursor solution had better photovoltaic performances compared to those(B1 and B2)obtained from the B precursor solution for the same y values.The stoichiometry of the film to achieve the best photovoltaic performance(the corresponding cell has the highest efficiency)is not the same for the A-group(prepared from the A precursor solution)and B-group films(prepared from the B precursor solution).The photovoltaic performance of the perovskite film is directly correlated to the crystallinity,morphology and defect sites of the film as evidenced by GIXRD,scanning electron microscopy(SEM)and transient photoluminescence(TRPL)data.The morphology of the mixed-halide perovskite films depends on the homogeneity of the halide stoichiometries.The A-group films with more possible halide stoichiometries have better crystallinity and continuity compared to those of the B-group films,probably due to the difference in the crystallization rates for the two group perovskite films.Therefore,for preparing mixed-halide perovskites with the same average halide stoichiometry,starting materials that can produce perovskite films with more halide stoichiometries are a better choice.展开更多
Facile fabrication of two-dimensional nanostructures to expose more active sites is a critical factor in developing high-efficiency transition metal sulfide material catalysts.Herein,the one-step solvent-free solid-st...Facile fabrication of two-dimensional nanostructures to expose more active sites is a critical factor in developing high-efficiency transition metal sulfide material catalysts.Herein,the one-step solvent-free solid-state method was developed to synthesize Co_(9)S_(8)(denoted as S-Co_(9)S_(8))with a nanoflake structure and much improved electronic conductivity,and the carbon substrate or template was not required.Benefiting from the unique properties.展开更多
Fabricating solution-processable composite materials of transition metal dichalcogenides(TMDs)with ultrasmall noble metal structures employing an easy preparation method poses a significant challenge.In this study,we ...Fabricating solution-processable composite materials of transition metal dichalcogenides(TMDs)with ultrasmall noble metal structures employing an easy preparation method poses a significant challenge.In this study,we utilized a green,one-step synthetic method by directly employing electrochemical lithium intercalation-based exfoliated metallic TMD nanosheets(MoS_(2),WS_(2),and TiS_(2))to reduce palladium ions(Pd^(2+))to metallic Pd^(0),leading to the deposition on their surfaces.The resulting Pd nanoparticles(Pd NPs)in composites(Pd-MoS_(2),Pd-WS_(2),and Pd-TiS_(2))were found to be amorphous,with a size ranging from 0.81 to 1.37 nm.The impact of Pd NP size on hydrogen evolution reaction(HER)activity was elucidated.Among the fabricated composites,Pd-MoS_(2) exhibits the best HER performance,attributed to its smallest Pd NP size(0.81 nm).It shows an overpotential of 70 mV at a current density of 10 mA cm^(-2),along with a Tafel slope of 43 mV dec^(-1).These HER performance metrics surpass those of most Pd-decorated 2D catalysts.展开更多
In this work,a one step solvothermal method was used to synthesize uniform anisotropic hexagonal and cylindrical hematite nanoplates in the presence of methanol and ethylene di-amine.The phase and morphology of the sa...In this work,a one step solvothermal method was used to synthesize uniform anisotropic hexagonal and cylindrical hematite nanoplates in the presence of methanol and ethylene di-amine.The phase and morphology of the samples were confirmed by X-ray diffraction(XRD)and electron microscopy.Photocatalytic degradation of methylene blue(MB)was carried out using two different hematite nanoplates to compare their catalytic performance.A systematic study of different parameters affecting the photodegradation of MB was performed.Hexagonal nanoplates exposing(110),(102)and(104)facets exhibit enhanced photocatalytic activity compared to the cylindrical nanoplates that expose only(110)and(102)facets,confirming that the high catalytic activity of the hexagonal nanoplates is attributed to the exposure of more catalytically active facets.展开更多
文摘Vanadium nitrides were prepared via one step method of carbothermal reduction and nitridation of vanadium trioxide. Thermalgravimetric analysis （TGA） and X-ray diffraction were used to determine the reaction paths of vanadium carbide, namely the following sequential reaction： V2O3→V8C7 in higher temperature stage, the rule of vanadium nitride synthesized was established, and defined conditions of temperature for the production of the carbides and nitrides were determined. Vanadium oxycarbide may consist in the front process of carbothermal reduction of vanadium trioxide. In one step method for vanadium nitride by carbothermal reduction and nitridation of vanadium trioxide, the nitridation process is simultaneous with the carbothermal reduction. A one-step mechanism of the carbothermal reduction with simultaneous nitridation leaded to a lower terminal temperature in nitridation process for vanadium nitride produced, compared with that of carbothermal reduction process without nitridation. The grain size and shape of vanadium nitride were uniform, and had the shape of a cube. The one step method combined vacuum carborization and nitridation （namely two step method） into one process. It simplified the technological process and decreased the costs.
基金Supported by Opening Program of Physiologial Key Laboratory for Cultivation of Tropical Crops in Hainan Province(Key Opening Bio-logial Laboratory of Rubber of Ministry of Agriculture/Breeding Basein State and Provincial Key Laboratory)(KLOF0907)Major and Special Program for Cultivation of Genetically Modified New Varieties(No.2009ZX08012-014B)+1 种基金National Natural Science Foundation of China(No.30971711)Natural Science Foundation in Jiangsu Province(No.BK2009309)~~
文摘[Objective] The aim of this study was to extract RNA,DNA and protein from plants by using modified one step method.[Method]CTAB was used for the modifying of Biozol-based one step extraction method,which was then used for the isolation of RNA,DNA and protein from the roots of maize（Zea mays L.）,soybean（Glycine max L.）,alfalfa（Medicago sativa L.）and cucumber（Cucumis sativus L.）.And the heme oxygenase-1 gene（HO-1）and calcium-dependent protein kinase-1 gene（CDPK1）,as well as HO-1 protein were identified.[Result]The result of UV spectrophotometer determination and agarose gel electrophoresis analysis showed that the purity of obtained RNA and DNA sample was relatively high;HO-1 and CDPK1 gene exhibited the positive signals checked by RT-PCR;the extracted protein could be used for western blotting analysis;the whole isolation procedure cost 3 h.[Conclusion]This method can be used as a good reference for researcher and will offer a better value with a wide range of applications.
基金Project supported by the National Natural Science Foundation of China (No. 51075187)
文摘A membrane element model with bending modification based on element moment equilibrium is proposed for the first time by the authors, who apply the element model in one step inverse method and simulate the forming process of a flower-shaped box using the membrane element model with and without this modification. The numerical results are compared with those of the incremental method to verify the validity of the element model developed in this paper.
基金the National Natural Science Foundation of China(Nos.21103024,61171008)Natural Science Foundation of Zhejiang Province(No.LY19B060006)+1 种基金National Key Research and Development Program of China(No.2018YFB1502900)Technology Development Project of Jiaxing University(No.70518047)。
文摘Graphitic carbon nitride(g-C_(3)N_(4))-based materials are regarded as one of the most potential photocatalysts for utilizing solar energy.In this work,we reported a facile one step in-situ hydrothermal-roasting method for preparing honeycomb-like g-C_(3)N_(4)/CeO_(2) nanosheets with abundant oxygen vacancies(g-C_(3)N_(4)/CeO_(2)-x).The hydrothermal-roasting and incomplete-sealed state can(i)generate an in-situ reducing atmosphere(CO,N2,NH3) to tune the concentration of oxygen vacancies in CeO_(2);(ii) beneficial to prevent continuous growth of g-C_(3)N_(4) and results in honeycomb-like g-C_(3)N_(4)/CeO_(2)-x hybrid nanosheets.What is more,the g-C_(3)N_(4)/CeO_(2)-x photocatalyst exhibited extended photoresponse range,increased specific surface area and obviously enhanced separation efficiency of photogenerated electron-hole pairs.As a proof-of-concept application,the optimized g-C_(3)N_(4)/CeO_(2)-xnanosheets could achieve 98% removal efficiency for Cr(Ⅵ) under visible light irradiation(λ≥420 nm)within 2.5 h,which is significantly better than those of pure g-C_(3)N_(4) and CeO_(2).This work provides a new idea for more rationally designing and constructing g-C_(3)N_(4)-based catalysts for efficient extended photochemical application.
文摘Organic-inorganic lead halide perovskites represent a group of materials with diverse structures and promising optical/optoelectronic properties.The performance of perovskite based solar cells relies tremendously on the structure/properties of the absorber.The physicochemical properties of the perovskite active layer depend on the substrate,preparation methods,environments and the starting materials.In this study,we investigated the effects of starting materials in the precursor solution on the physicochemical properties of the resulting one-step spin coated MA_(0.8)FA_(0.2)PbI_(3-y)Br_(y) film and the photovoltaic performance of the corresponding inverted(p-i-n)perovskite solar cells.Two precursor solutions containing exactly the same atom stoichiometry were prepared from two different groups of starting materials(Group A:CH_(3)NH_(3)I,CH(NH_(2))_(2)I,CH_(3)NH_(3)Br,and PbI_(2);Group B:CH_(3)NH_(3)I,CH(NH_(2))_(2)I,PbI_(2) and PbBr_(2)).The MA_(0.8)FA_(0.2)PbI_(3-y)Br_(y) films(A1 and A2)prepared from the A precursor solution had better photovoltaic performances compared to those(B1 and B2)obtained from the B precursor solution for the same y values.The stoichiometry of the film to achieve the best photovoltaic performance(the corresponding cell has the highest efficiency)is not the same for the A-group(prepared from the A precursor solution)and B-group films(prepared from the B precursor solution).The photovoltaic performance of the perovskite film is directly correlated to the crystallinity,morphology and defect sites of the film as evidenced by GIXRD,scanning electron microscopy(SEM)and transient photoluminescence(TRPL)data.The morphology of the mixed-halide perovskite films depends on the homogeneity of the halide stoichiometries.The A-group films with more possible halide stoichiometries have better crystallinity and continuity compared to those of the B-group films,probably due to the difference in the crystallization rates for the two group perovskite films.Therefore,for preparing mixed-halide perovskites with the same average halide stoichiometry,starting materials that can produce perovskite films with more halide stoichiometries are a better choice.
基金supported by the National Natural Science Foundation of China(12274471,11922415)Guangdong Basic and Applied Basic Research Foundation(2022A1515011168,2019A1515011718)+1 种基金Key Research&Development Program of Guangdong Province,China(2019B110209003)supported by the Guangzhou Basic and Applied Basic Research Foundation(202102021118).
文摘Facile fabrication of two-dimensional nanostructures to expose more active sites is a critical factor in developing high-efficiency transition metal sulfide material catalysts.Herein,the one-step solvent-free solid-state method was developed to synthesize Co_(9)S_(8)(denoted as S-Co_(9)S_(8))with a nanoflake structure and much improved electronic conductivity,and the carbon substrate or template was not required.Benefiting from the unique properties.
基金the General Research Fund(GRF)support from the Research Grants Council of the Hong Kong Special Administrative Region,China(project no.CityU11308923)the Basic Research Project from Shenzhen Science and Technology Innovation Committee in Shenzhen,China(no.JCYJ20210324134012034)+2 种基金the Applied Research Grant of City University of Hong Kong(project no.9667247)the Chow Sang Sang Group Research Fund of City University of Hong Kong(project no.9229123)the funding support from the Seed Collaborative Research Fund Scheme of the State Key Laboratory of Marine Pollution,which receives regular research funding from the Innovation and Technology Commission(ITC)of the Hong Kong SAR Government.
文摘Fabricating solution-processable composite materials of transition metal dichalcogenides(TMDs)with ultrasmall noble metal structures employing an easy preparation method poses a significant challenge.In this study,we utilized a green,one-step synthetic method by directly employing electrochemical lithium intercalation-based exfoliated metallic TMD nanosheets(MoS_(2),WS_(2),and TiS_(2))to reduce palladium ions(Pd^(2+))to metallic Pd^(0),leading to the deposition on their surfaces.The resulting Pd nanoparticles(Pd NPs)in composites(Pd-MoS_(2),Pd-WS_(2),and Pd-TiS_(2))were found to be amorphous,with a size ranging from 0.81 to 1.37 nm.The impact of Pd NP size on hydrogen evolution reaction(HER)activity was elucidated.Among the fabricated composites,Pd-MoS_(2) exhibits the best HER performance,attributed to its smallest Pd NP size(0.81 nm).It shows an overpotential of 70 mV at a current density of 10 mA cm^(-2),along with a Tafel slope of 43 mV dec^(-1).These HER performance metrics surpass those of most Pd-decorated 2D catalysts.
基金supported by the NSFC(51125001,51172005)Beijing Natural Science Foundation(2122022)+2 种基金NSFC-RGC Joint Research Scheme(51361165201)Doctoral Program of the Ministry of Education of China(20120001110078)the Interdisciplinary Project of Beijing New Star Plan of Science and Technology.
文摘In this work,a one step solvothermal method was used to synthesize uniform anisotropic hexagonal and cylindrical hematite nanoplates in the presence of methanol and ethylene di-amine.The phase and morphology of the samples were confirmed by X-ray diffraction(XRD)and electron microscopy.Photocatalytic degradation of methylene blue(MB)was carried out using two different hematite nanoplates to compare their catalytic performance.A systematic study of different parameters affecting the photodegradation of MB was performed.Hexagonal nanoplates exposing(110),(102)and(104)facets exhibit enhanced photocatalytic activity compared to the cylindrical nanoplates that expose only(110)and(102)facets,confirming that the high catalytic activity of the hexagonal nanoplates is attributed to the exposure of more catalytically active facets.
