Surface-confined metal-organic frameworks have emerged as versatile structures with a broad spectrum of applications such as nanoelectronics,catalysis,sensing,and molecular storage,owing to their unique structural and...Surface-confined metal-organic frameworks have emerged as versatile structures with a broad spectrum of applications such as nanoelectronics,catalysis,sensing,and molecular storage,owing to their unique structural and electronic properties.However,the exploration and optimization of molecular networks typically involve resource-intensive trial-and-error experiments.The complexity comes from factors like metal nodes,organic ligands,substrates,and the preparation conditions.To address this challenge,highthroughput methodologies have been used in materials exploration.In this work,we explored a highthroughput method for preparing sub-monolayer metals with continuous coverage spread on metal surfaces.By employing a physical mask during metal deposition under ultra-high vacuum conditions,we achieved sample libraries with copper(Cu)and silver(Ag)adatoms on the metal substrates,and constructed surface-supported metal-organic frameworks with varying metal-to-molecule stoichiometric ratios.This approach facilitates the exploration of surface-confined metal-organic frameworks,particularly in terms of varying metal-to-ligand stoichiometric ratios,offering an efficient pathway to unlock the potential of these intricate two-dimensional networks.展开更多
Most current catalyst preparation methods cause pollution to air, water and land with the use of hazardous chemicals, lengthy operation time, high energy input and excessive water usage. The development of green catal...Most current catalyst preparation methods cause pollution to air, water and land with the use of hazardous chemicals, lengthy operation time, high energy input and excessive water usage. The development of green catalyst preparation is necessary to prevent and eliminate waste from each step of the catalyst preparation. We summarize recent progress in the application of cold plasmas for green catalyst preparation. Cold plasma preparation can reduce the catalyst size, improve the dispersion and enhance catalyst-support interaction with the use of less or no hazardous chemicals. These improvements also lead to the enhancement of catalyst activity and stability. An alternative room temperature electron reduction with a non-hydrogen plasma as an electron source was developed for the reduction of noble metal ions in which no hazardous chemical reducing agent or hydrogen was needed. This creates many opportunities for the development of supported catalysts with heat sensitive substrates, including metal organic frameworks （MOFs）, covalent organic framework（COFs）, high surface area carbon, peptide, DNA, proteins and others. A novel floating metal catalyst on a water（or solution） surface has been established. Template removal using low temperature cold plasmas also leads to the formation of high surface area porous materials with characteristics that are normally only obtainable with high temperature calcination, but sintering can be avoided. Micro combustion has been developed for the removal of carbon template using cold plasma. This is promising for preparing many structured oxides in a simple way with no use of auxiliary chemicals. Many opportunities exist for the use of cold plasmas to make multi-metallic oxides. Some future development ideas are addressed.展开更多
A new method was used to preparing genomic DNA from Microbacterium sp.quickly and efficiently.DNA quantity and purity was measured by UV absorbance.Integrity of the genomic DNA was tested by agarose gel eletrophoresis...A new method was used to preparing genomic DNA from Microbacterium sp.quickly and efficiently.DNA quantity and purity was measured by UV absorbance.Integrity of the genomic DNA was tested by agarose gel eletrophoresis.The DNA prepared by this method was sufficiently pure for PCR.This method saves time and cost,practices easily as well.展开更多
We report a reproducible approach in preparing high-quality overdoped Bi2 Sr2 CaCu2 08＋δ （Bi2212） single crystals by annealing Bi2212 crystals in high oxygen pressure followed by a fast quenching. In this way, hig...We report a reproducible approach in preparing high-quality overdoped Bi2 Sr2 CaCu2 08＋δ （Bi2212） single crystals by annealing Bi2212 crystals in high oxygen pressure followed by a fast quenching. In this way, high-quality overdoped and heavily overdoped Bi2212 single crystals are obtained by controlling the annealing oxygen pressure. We find that, beyond a limit of oxygen pressure that can achieve most heavily overdoped Bi2212 with a Tc N63 K, the annealed Bi2212 begins to decompose. This accounts for the existence of the hole-doping limit and thus the Tc limit in the heavily overdoped region of Bi2212 by the oxygen annealing process. These results provide a reliable way in preparing high-quality overdoped and heavily overdoped Bi2212 crystals that are important for studies of the physical properties, electronic structure and superconductivity mechanism of the cuprate superconductors.展开更多
We need more research that will fulfill the needs of athletes and coaches.This is a common statement,highly relevant nowadays only a few weeks before the commencement of the Paris 2024 Olympic Games.To fill this gap,w...We need more research that will fulfill the needs of athletes and coaches.This is a common statement,highly relevant nowadays only a few weeks before the commencement of the Paris 2024 Olympic Games.To fill this gap,we have identified 6 topics that we feel coaches and athletes would be interested in learning more to optimize their preparation for the Olympics.These topics are.展开更多
In this paper, we report an improved method for preparing 2--alkoxy 5 fluoro--3H --4--pyrimidone from 2--chloro--5--fluoro--3H--4--pyrimidone and sodium alkoxide under normal pressure at reflux temperature. Some new c...In this paper, we report an improved method for preparing 2--alkoxy 5 fluoro--3H --4--pyrimidone from 2--chloro--5--fluoro--3H--4--pyrimidone and sodium alkoxide under normal pressure at reflux temperature. Some new compounds were synthesized in higher yield by this method.展开更多
A scheme to generate superpositions of coherent states with variable amplitudes,phases and weighting factors is proposed.It provides experimental possibility for preparing an arbitrary Schrödinger cat state.
Induction-Polymerization is a novel method for preparing polymers of regular structure. In the presence of a special macromolecular compound, monomer molecules are aggregeted regularly around one or more growth points...Induction-Polymerization is a novel method for preparing polymers of regular structure. In the presence of a special macromolecular compound, monomer molecules are aggregeted regularly around one or more growth points and polymerized to polymer of regular structure. Regularity of structure of the polyacrylamide prepared by this means has been verified with electron diffractograms, DSC curve and IR spectrum of the polymer.展开更多
This investigation describes the one step preparation of potassium carbonate by electrolysis of potas-sium chloride solution in electrolyzers with various Nation membranes.Potassium bicarbonate solution wasfed to the ...This investigation describes the one step preparation of potassium carbonate by electrolysis of potas-sium chloride solution in electrolyzers with various Nation membranes.Potassium bicarbonate solution wasfed to the cathode compartment,where it was converted into carbonate by reaction with the hydroxideformed at cathode.Because of the low OH^- concentration in the cathode compartment,the back migrationof OH^- through the membrane was almost negligible,resulting in a higher current efficiency,say 90% or more.In this study,electroconductivity,mass transfer,current efficiency and cell voltage were measured.Thefeasibility of the process was discussed and the optimal conditions examined.展开更多
Several regional maps of mafic dyke swarms(e.g.,Buchan and Ernst,2004,2013;Vuollo and Huhma,2005;Peng,2015)have been published in recent years,as well as an earlier global dyke compilation map(Ernst et al.,1996).
This paper reports a preparing process of quick moving leaf for TiNi shape memory alloy. Using the process. a series of quick moving leaves having different points of temperature. from 58 to 100℃. at which they jump ...This paper reports a preparing process of quick moving leaf for TiNi shape memory alloy. Using the process. a series of quick moving leaves having different points of temperature. from 58 to 100℃. at which they jump up have been made. The quick moving leaves will be fully qualified as the electric switches that open and close themselves at proper temperatures.展开更多
A new method for preparing SiC particle-reinforced aluminum matrix composites was introduced.In order to improve the ingot surface and homogeneity of structure,low frequency electromagnetic field was applied during th...A new method for preparing SiC particle-reinforced aluminum matrix composites was introduced.In order to improve the ingot surface and homogeneity of structure,low frequency electromagnetic field was applied during the direct chilling casting process.The experimental results show that the new method can be used to prepare SiC particle-reinforced aluminum matrix composites;under the effects of the low frequency electromagnetic field,the microstructure of ingot is refined and the distribution of SiC particles is improved.展开更多
Atomically dispersed catalysts have shown promising prospects in catalysis studies.Among all of the developed methods for synthesizing atomically dispersed catalysts,the photochemical approach has recently aroused muc...Atomically dispersed catalysts have shown promising prospects in catalysis studies.Among all of the developed methods for synthesizing atomically dispersed catalysts,the photochemical approach has recently aroused much attention owing to its simple procedure and mild preparation conditions involved.In the present study,we demonstrate the application of the photochemical method to synthesize atomically dispersed Pd catalysts on(001)‐exposed anatase nanocrystals and commercial TiO2(P25).The as‐prepared catalysts exhibit both high activity and stability in the hydrogenation of styrene and catalytic oxidation of CO.展开更多
Ferrate is an excellent water treatment agent for its multi functions in oxidation, disinfection, coagulation and adsorption, but its coagulation ability depends on its dosage and is after its oxidation. This paper f...Ferrate is an excellent water treatment agent for its multi functions in oxidation, disinfection, coagulation and adsorption, but its coagulation ability depends on its dosage and is after its oxidation. This paper focuses on preparing a new kind of ferrate combined with alum to enhance its coagulation function for water purification. An effective electrolysis reactor was designed and employed in the test. Some key parameters in the process of electrolysis concerning the preparation efficiency, such as the current density, temperature and alkalinity were also investigated. The proper conditions for ferrate alum preparation were determined. Under the condition of 5V given voltage, 6h electrolyzing interval, below 2% alum concentration (in weight), a combined liquid ferrate alum products was successfully prepared, which contained 0.0294 mol/L FeO 2- 4 and 0.0302 mol/L total soluble ferron with 2% Al 2O 3. There was no insoluble ferron produced by controlling an optimum electrochemical condition.展开更多
TiO2 nanomaterial is promising with its high potential and outstanding performance in photocatalytic environmental applications, such as CO2 conversion, water treatment, and air quality control. For many of these appl...TiO2 nanomaterial is promising with its high potential and outstanding performance in photocatalytic environmental applications, such as CO2 conversion, water treatment, and air quality control. For many of these applications, the particle size, crystal structure and phase, porosity, and surface area influence the activity of TiO2 dramatically. TiO2 nanomaterials with special structures and morphologies, such as nanospheres, nanowires, nanotubes, nanorods, and nanoflowers are thus synthesized due to their desired characteristics. With an emphasis on the different morphologies of TiO2 and the influence factors in the synthesis, this review summarizes fourteen TiO2 preparation methods, such as the sol-gel method, solvothermal method, and reverse micelle method. The TiO2 formation mechanisms, the advantages and disadvantages of the preparation methods, and the photocatalytic environmental application examples are proposed as well.展开更多
基金supported by National Natural Science Foundation of China(Nos.22072086,22302120).
文摘Surface-confined metal-organic frameworks have emerged as versatile structures with a broad spectrum of applications such as nanoelectronics,catalysis,sensing,and molecular storage,owing to their unique structural and electronic properties.However,the exploration and optimization of molecular networks typically involve resource-intensive trial-and-error experiments.The complexity comes from factors like metal nodes,organic ligands,substrates,and the preparation conditions.To address this challenge,highthroughput methodologies have been used in materials exploration.In this work,we explored a highthroughput method for preparing sub-monolayer metals with continuous coverage spread on metal surfaces.By employing a physical mask during metal deposition under ultra-high vacuum conditions,we achieved sample libraries with copper(Cu)and silver(Ag)adatoms on the metal substrates,and constructed surface-supported metal-organic frameworks with varying metal-to-molecule stoichiometric ratios.This approach facilitates the exploration of surface-confined metal-organic frameworks,particularly in terms of varying metal-to-ligand stoichiometric ratios,offering an efficient pathway to unlock the potential of these intricate two-dimensional networks.
基金supported by the National Natural Science Foundation of China(20990223 and 21476157)~~
文摘Most current catalyst preparation methods cause pollution to air, water and land with the use of hazardous chemicals, lengthy operation time, high energy input and excessive water usage. The development of green catalyst preparation is necessary to prevent and eliminate waste from each step of the catalyst preparation. We summarize recent progress in the application of cold plasmas for green catalyst preparation. Cold plasma preparation can reduce the catalyst size, improve the dispersion and enhance catalyst-support interaction with the use of less or no hazardous chemicals. These improvements also lead to the enhancement of catalyst activity and stability. An alternative room temperature electron reduction with a non-hydrogen plasma as an electron source was developed for the reduction of noble metal ions in which no hazardous chemical reducing agent or hydrogen was needed. This creates many opportunities for the development of supported catalysts with heat sensitive substrates, including metal organic frameworks （MOFs）, covalent organic framework（COFs）, high surface area carbon, peptide, DNA, proteins and others. A novel floating metal catalyst on a water（or solution） surface has been established. Template removal using low temperature cold plasmas also leads to the formation of high surface area porous materials with characteristics that are normally only obtainable with high temperature calcination, but sintering can be avoided. Micro combustion has been developed for the removal of carbon template using cold plasma. This is promising for preparing many structured oxides in a simple way with no use of auxiliary chemicals. Many opportunities exist for the use of cold plasmas to make multi-metallic oxides. Some future development ideas are addressed.
文摘A new method was used to preparing genomic DNA from Microbacterium sp.quickly and efficiently.DNA quantity and purity was measured by UV absorbance.Integrity of the genomic DNA was tested by agarose gel eletrophoresis.The DNA prepared by this method was sufficiently pure for PCR.This method saves time and cost,practices easily as well.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11190022,11334010 and 11534007the National Basic Research Program of China under Grant No 2015CB921000the Strategic Priority Research Program(B)of Chinese Academy of Sciences under Grant No XDB07020300
文摘We report a reproducible approach in preparing high-quality overdoped Bi2 Sr2 CaCu2 08＋δ （Bi2212） single crystals by annealing Bi2212 crystals in high oxygen pressure followed by a fast quenching. In this way, high-quality overdoped and heavily overdoped Bi2212 single crystals are obtained by controlling the annealing oxygen pressure. We find that, beyond a limit of oxygen pressure that can achieve most heavily overdoped Bi2212 with a Tc N63 K, the annealed Bi2212 begins to decompose. This accounts for the existence of the hole-doping limit and thus the Tc limit in the heavily overdoped region of Bi2212 by the oxygen annealing process. These results provide a reliable way in preparing high-quality overdoped and heavily overdoped Bi2212 crystals that are important for studies of the physical properties, electronic structure and superconductivity mechanism of the cuprate superconductors.
文摘We need more research that will fulfill the needs of athletes and coaches.This is a common statement,highly relevant nowadays only a few weeks before the commencement of the Paris 2024 Olympic Games.To fill this gap,we have identified 6 topics that we feel coaches and athletes would be interested in learning more to optimize their preparation for the Olympics.These topics are.
基金The project is supported by Natural Science Foundation of Shandong.
文摘In this paper, we report an improved method for preparing 2--alkoxy 5 fluoro--3H --4--pyrimidone from 2--chloro--5--fluoro--3H--4--pyrimidone and sodium alkoxide under normal pressure at reflux temperature. Some new compounds were synthesized in higher yield by this method.
基金Supported by the National Natural Science Foundation of China under Grant No.69438010.
文摘A scheme to generate superpositions of coherent states with variable amplitudes,phases and weighting factors is proposed.It provides experimental possibility for preparing an arbitrary Schrödinger cat state.
文摘Induction-Polymerization is a novel method for preparing polymers of regular structure. In the presence of a special macromolecular compound, monomer molecules are aggregeted regularly around one or more growth points and polymerized to polymer of regular structure. Regularity of structure of the polyacrylamide prepared by this means has been verified with electron diffractograms, DSC curve and IR spectrum of the polymer.
文摘This investigation describes the one step preparation of potassium carbonate by electrolysis of potas-sium chloride solution in electrolyzers with various Nation membranes.Potassium bicarbonate solution wasfed to the cathode compartment,where it was converted into carbonate by reaction with the hydroxideformed at cathode.Because of the low OH^- concentration in the cathode compartment,the back migrationof OH^- through the membrane was almost negligible,resulting in a higher current efficiency,say 90% or more.In this study,electroconductivity,mass transfer,current efficiency and cell voltage were measured.Thefeasibility of the process was discussed and the optimal conditions examined.
文摘Several regional maps of mafic dyke swarms(e.g.,Buchan and Ernst,2004,2013;Vuollo and Huhma,2005;Peng,2015)have been published in recent years,as well as an earlier global dyke compilation map(Ernst et al.,1996).
文摘This paper reports a preparing process of quick moving leaf for TiNi shape memory alloy. Using the process. a series of quick moving leaves having different points of temperature. from 58 to 100℃. at which they jump up have been made. The quick moving leaves will be fully qualified as the electric switches that open and close themselves at proper temperatures.
基金Funded by the National Natural Science Foundation of China(51574075)the National Basic Research Program of China(2012CB723307)+3 种基金the Hi-Tech Research and Development Program of China(2013AA032402)the Scientific Research Fund of Liaoning Provincial Education Department(L2013110)the Bureau of Shenyang city Science and Technology Project(F14-231-1-01)the Fundamental Research Funds for the Central Universities(120409005)
文摘A new method for preparing SiC particle-reinforced aluminum matrix composites was introduced.In order to improve the ingot surface and homogeneity of structure,low frequency electromagnetic field was applied during the direct chilling casting process.The experimental results show that the new method can be used to prepare SiC particle-reinforced aluminum matrix composites;under the effects of the low frequency electromagnetic field,the microstructure of ingot is refined and the distribution of SiC particles is improved.
基金supported by the Ministry of Science and Technology of nano major research projects(2015CB932303)the National Natural Science Foundation of China(21420102001,21131005,21333008,21390390)~~
文摘Atomically dispersed catalysts have shown promising prospects in catalysis studies.Among all of the developed methods for synthesizing atomically dispersed catalysts,the photochemical approach has recently aroused much attention owing to its simple procedure and mild preparation conditions involved.In the present study,we demonstrate the application of the photochemical method to synthesize atomically dispersed Pd catalysts on(001)‐exposed anatase nanocrystals and commercial TiO2(P25).The as‐prepared catalysts exhibit both high activity and stability in the hydrogenation of styrene and catalytic oxidation of CO.
文摘Ferrate is an excellent water treatment agent for its multi functions in oxidation, disinfection, coagulation and adsorption, but its coagulation ability depends on its dosage and is after its oxidation. This paper focuses on preparing a new kind of ferrate combined with alum to enhance its coagulation function for water purification. An effective electrolysis reactor was designed and employed in the test. Some key parameters in the process of electrolysis concerning the preparation efficiency, such as the current density, temperature and alkalinity were also investigated. The proper conditions for ferrate alum preparation were determined. Under the condition of 5V given voltage, 6h electrolyzing interval, below 2% alum concentration (in weight), a combined liquid ferrate alum products was successfully prepared, which contained 0.0294 mol/L FeO 2- 4 and 0.0302 mol/L total soluble ferron with 2% Al 2O 3. There was no insoluble ferron produced by controlling an optimum electrochemical condition.
基金the supports from the Clean Coal ProgramSchool of Energy Resources in Wyoming
文摘TiO2 nanomaterial is promising with its high potential and outstanding performance in photocatalytic environmental applications, such as CO2 conversion, water treatment, and air quality control. For many of these applications, the particle size, crystal structure and phase, porosity, and surface area influence the activity of TiO2 dramatically. TiO2 nanomaterials with special structures and morphologies, such as nanospheres, nanowires, nanotubes, nanorods, and nanoflowers are thus synthesized due to their desired characteristics. With an emphasis on the different morphologies of TiO2 and the influence factors in the synthesis, this review summarizes fourteen TiO2 preparation methods, such as the sol-gel method, solvothermal method, and reverse micelle method. The TiO2 formation mechanisms, the advantages and disadvantages of the preparation methods, and the photocatalytic environmental application examples are proposed as well.
