BACKGROUND:Tracheal intubation(TI)is a fundamental procedure for securing the airway or assisting ventilation in emergency medicine.Tracheal intubation in the lateral position(TILP)has been utilized in clinical practi...BACKGROUND:Tracheal intubation(TI)is a fundamental procedure for securing the airway or assisting ventilation in emergency medicine.Tracheal intubation in the lateral position(TILP)has been utilized in clinical practice,demonstrating potential advantages in specific scenarios,including emergency settings.However,there is a lack of comprehensive reviews and practical protocols on TILP application.To address this gap,we performed a narrative review,and provided evidence-based recommendations to formulate a practice protocol,to assist clinicians to effectively apply TILP.METHODS:We conducted a narrative review of TILP applications and developed recommendations based on clinical research evidence and clinical experience.Delphi method was used among the TILP consortium to grade the strength of the recommendations and to help reach consensus.The practice protocols were formulated as warranted by advancements in medical knowledge,technology,and practice.RESULTS:This narrative review summarized the current evidence on TILP application,highlighting its safety,efficacy,challenges,and potential complications.In total,24 recommendations and a clinical protocol for TILP application in emergency patients were established.CONCLUSION:TILP is a valuable technique in emergency medicine.We reviewed its application in emergency settings and formulated recommendations along with a clinical practice protocol.Future studies are needed to evaluate the safety and efficacy of TILP,broaden its scope of application,and explore effective training protocols.展开更多
The effects of different kinds of ionic liquids(ILs)on the caking property of Shenhua long-flame coal(SHLC)were studied.SHLC and its residue after[N_(4441)][Cl]treatment under optimum conditions were characterized by ...The effects of different kinds of ionic liquids(ILs)on the caking property of Shenhua long-flame coal(SHLC)were studied.SHLC and its residue after[N_(4441)][Cl]treatment under optimum conditions were characterized by Fourier transform infrared spectroscopy(FT-IR),thermogravimetric analysis(TG),X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),Raman spectroscopy,and pyrolysis-gas chromatography and mass-spectrometric analysis(Py-GC/MS).The results showed that the ILs used could extract the poorly-caking components from SHLC,and[N_(4441)][Cl]with C_(3)H_(6)O as a solvent exhibited the best effect among the ILs and solvents used.[N_(4441)][Cl]could destroy the H bonds in SHLC,and the structure of the cross-linked macromolecules of SHLC was loosed,leading to the release of the small molecules within the macromolecular framework of SHLC.Additionally,[N_(4441)][Cl]could easily penetrate into the interior of the relaxed SHLC and break the weak covalent bonds(e.g.,C-O bonds)of the macromolecules of SHLC.As a result,aromatic hydrocarbons with 3‒5 rings and aliphatic side chains,which are the precursor of the poorly-caking components,were formed and were then extracted from SHLC by C_(3)H_(6)O.Consequently,[N_(4441)][Cl]treatment could decrease the caking property,thermal ability,and macromolecular size of SHLC.展开更多
Polystyrene(PS)waste was depolymerized using a low-temperature pyrolysis treatment(LTPT)to increase its caking index.The mechanism of caking index modification was revealed by using Fourier transform infrared spectros...Polystyrene(PS)waste was depolymerized using a low-temperature pyrolysis treatment(LTPT)to increase its caking index.The mechanism of caking index modification was revealed by using Fourier transform infrared spectroscopy,thermogravimetric(TG)analysis,pyrolysis-gas chromatography with mass spectrometric detection,and solid-state^(13)C nuclear magnetic resonance spectroscopy.The crucible coal-blending coking tests were carried out using an industrial coal mixture and the treated-PS with the highest caking index(PS300)or raw PS.Some properties of the resultant cokes were also analyzed.It was demonstrated that the caking index of PS dramatically increased by LTPT;however,exceeding 300℃ did not yield any benefit.The caking index increased due to the formation of the caking components,whose molecules are medium in size,caused by LTPT.Additionally,the coke reactivity index of the coke obtained from the mixture containing PS300 decreased by 5.1%relative to that of the coke made from the mixture with PS and the coke strength after reaction index of the former increased by 7.3% compared with that of the latter,suggesting that the ratio of depolymerized PS used for coal-blending coking could increase relative to that of PS.展开更多
Grain growth of magnesium(Mg)and its hydride is one of the main reasons for kinetic and capacity degradation during the hydrogen absorption and desorption cycles.To solve this problem,herein we propose a novel method ...Grain growth of magnesium(Mg)and its hydride is one of the main reasons for kinetic and capacity degradation during the hydrogen absorption and desorption cycles.To solve this problem,herein we propose a novel method involving synergistic effect of inside embedded metals and outside coated graphene to limit the growth of Mg and its hydride grains.The graphene coated Mg-Y-Al alloys were selected as a model system for demonstrating this positive effect where the Mg_(91)Y_(3)Al_(6)alloy was first prepared by rapidly solidified method and then high-pressure milled with 5 wt%graphene upon 5 MPa hydrogen gas for obtaining in-situ formed YAl_(2)and YH_(3)embedded in the MgH_(2)matrix with graphene shell(denoted as MgH_(2)-Y-Al@GR).In comparison to pure MgH_(2),the obtained MgH_(2)-Y-Al@GR composites deliver much better kinetics and more stable cyclic performance.For instance,the MgH_(2)-Y-Al@GR can release about 6.1 wt%H_(2)within 30 min at 300℃ but pure MgH_(2)only desorbs∼1.5 wt%H_(2).The activation energy for desorption of MgH_(2)-Y-Al@GR samples is calculated to be 75.3±9.1 kJ/mol that is much lower than approximately 160 kJ/mol for pure MgH_(2).Moreover,its capacity retention is promoted from∼57%of pure MgH_(2)to∼84%after 50th cycles without obvious particle agglomeration and grain growth.The synergistic effect of outside graphene coating with inside embedded metals which could provide a huge number of active sites for catalysis as well as inhibit the grain growth of Mg and its hydride is believed to be responsible for these.展开更多
Reducing coke use is an effective measure to reduce carbon emission and energy consumption in the blast furnace(BF)ironmaking.Essentially,BF is a high-temperature moving bed reactor,where complex physical transformati...Reducing coke use is an effective measure to reduce carbon emission and energy consumption in the blast furnace(BF)ironmaking.Essentially,BF is a high-temperature moving bed reactor,where complex physical transformations coupled with complicated reactions occur.This makes it challenging to investigate the factors determining BF performance with the conventional method.A multi-physical field coupling mathematical model of BF was thus developed to describe its mass and heat transfer as well as its intrinsic reactions.Then,the proposed model was validated with the production data.Under coupling conditions,influences of dominating reactions on BF performance(temperature distribution,gas distribution,iron formation reaction,and direct reduction degree)were revealed.The results indicated that coke combustion,indirect reduction,and direct reduction of iron ore mainly took place nearby the shaft tuyere,cohesive zone,and dripping zone,respectively.Besides,the rate of coke solution loss reaction was increased with the rising coke porosity in the cohesive zone.Considering the effect of coke porosity on the efficiency and stability of BF,the coke porosity of 0.42 was regarded as a reasonable value.展开更多
The Chinese standard method of GB/T 4000e2017 was unable to accurately measure the coke thermal properties in the large blast furnace.Therefore,the coke compressive strength(CCS)test at a high temperature was designed...The Chinese standard method of GB/T 4000e2017 was unable to accurately measure the coke thermal properties in the large blast furnace.Therefore,the coke compressive strength(CCS)test at a high temperature was designed to examine the coke thermal properties.Then,the large-scale coke model(sp^(2)C_(17421)sp^(3)C_(6579))was established.After,the ReaxFF molecular dynamics simulations were implemented to mimic the coke solution loss(CSL)and the CCS at the high temperature.It was found that the adsorption energy and the diffusion energy of micropores were greater than those of mesopores and macropores,indicating that the CSL reaction mainly happened in the coke micropore.It was discovered that the CSL reaction mechanism was the sp^(3)C oxidization mechanism with the transient state of ketene structure.And,it was detected that the CCS process was divided into the plastic deformation,the instantaneous fracture and the elastic deformation and yield,which was caused by the local reconstruction,the overall folding and the center stretching of carbon layer,respectively.By comparing simulated results with experiments,it was proved that obtained mechanisms were valid.The proposed experimental and simulated methods provided a novel method to measure and understand the coke thermal properties.展开更多
Abandoned mines are rich in geothermal resources.In this article,the feasibility of applying a water resource heating system in abandoned mines is explored,adopting mine water in the extraction zone as the research ob...Abandoned mines are rich in geothermal resources.In this article,the feasibility of applying a water resource heating system in abandoned mines is explored,adopting mine water in the extraction zone as the research object.First,the utilization mode of geothermal resources in abandoned mines is introduced,and the applicable scenarios of different mine water heating methods are clarified.Second,to prevent the heat transfixion phenomenon caused by an irrational arrangement of pumping wells,a three-dimensional numerical calculation model for multiphysical field coupling of the pumping wells of a water source heat pump in abandoned mines is established,and 14 distinct types of well arrangements are simulated.According to the occurrence degree of heat transfixion,the most reasonable arrangement of pumping wells is selected.The influences of different recharge tempera-tures,pumping and recharging flow rates,well spacings,hydraulic gradients,aquifer thicknesses,porosities and other factors on the pumping temperature are studied according to the selected pumping and recharging well arrangement scheme.Finally,by choosing a residential building as the analysis object,a simulation model of the abandoned mine water source heat pump heating system is constructed,which is compared with a gas boiler heating system,revealing the energy savings and environmental protection benefits of the abandoned mine water source heat pump system.The results of this paper provide a scientific basis for the utilization of mine water geothermal resources,which can facilitate the transformation of abandoned mines and provide theoretical and technical guidance in engineering practice.展开更多
The development of pharmaceutical analytical methods represents one of the most significant aspects of drug development. Recent advances in microfabrication and microfluidics could provide new approaches for drug anal...The development of pharmaceutical analytical methods represents one of the most significant aspects of drug development. Recent advances in microfabrication and microfluidics could provide new approaches for drug analysis, including drug screening, active testing and the study of metabolism. Microfluidic chip technologies, such as lab-on-a-chip technology, three-dimensional (3D) cell culture, organs-on-chip and droplet techniques, have all been developed rapidly. Microfluidic chips coupled with various kinds of detection techniques are suitable for the high-throughput screening, detection and mechanistic study of drugs. This review highlights the latest (2010–2018) microfluidic technology for drug analysis and discusses the potential future development in this field.展开更多
Shenmu(SM)subbituminous coal without caking property was treated by low-temperature rapid pyrolysis(LTRP)to modify its caking and coking properties.The treated samples were characterized by Fourier transform infrared ...Shenmu(SM)subbituminous coal without caking property was treated by low-temperature rapid pyrolysis(LTRP)to modify its caking and coking properties.The treated samples were characterized by Fourier transform infrared spectrometry,vitrinite reflectance,and X-ray diffraction to determine the modification mechanism.Moreover,caking index(G)and coking indices(mechanical strength,coke reactivity,and coke strength after reaction)were employed to evaluate caking and coking properties,respectively.The results showed that SM coal was gradually upgraded with increasing processing temperature.Furthermore,the G values for the treated samples were significantly higher than that for SM coal,and G reached the maximum value at 450℃,implying the modification of caking property and the existence of an optimum temperature(450℃).Additionally,laboratory coking determinations showed that LTRP increased the mechanical strength of coke and coke strength after reaction and decreased coke reactivity when the treated coals were used in the coal blends instead of raw SM coal.Overall,LTRP treatment is effective to improve the caking and coking properties of SM coal.A mechanism was proposed for the modification.Suitable upgrading degree with suitable molecular masses and some releasable hydrogen-rich donor species present within the coal,which dominate the development of caking property,is important.展开更多
TiO_(2)-based materials have been considered as one of most promising alternatives for high-performance Li(Na)-ion batteries because of the low cost,simple composition,easy synthesis,good environmental protection,exce...TiO_(2)-based materials have been considered as one of most promising alternatives for high-performance Li(Na)-ion batteries because of the low cost,simple composition,easy synthesis,good environmental protection,excellent safety and relatively high specific capacity.Nonetheless,the inferior electronic conductivity and poor ion diffusion coefficients are the biggest bottlenecks that restrict the popular application.Much effort has been focused on resolving these problems toward large-scale applications,and numerous significant advances have been accomplished.In the present work,a comprehensive overview of structure characteristics,electrochemical reaction mechanism and modification strategies of TiO_(2)-based materials was presented.The recent advances of various efficient ways for improving conductivity,Li(Na)storage capacity,rate capability and cycle stability are systematically summarized,including surface engineering,constructing composite and element doping,etc.Constructing TiO_(2)-based materials with novel porous heterogeneous core-shell structures have been regarded as one of the most effective ways to resolve these challenges.Finally,the future research directions and development prospects of TiO_(2)-based anode materials used in the manufacture of high-performance Li(Na)-ion batteries are prospected.This review can provide important comprehension for the construction and optimization of highperformance of TiO_(2)-based anode materials.展开更多
The kinetics of coke solution loss reaction with and without sodium carbonate were investigated under the reaction atmosphere of carb on dioxide. The variables of gas flow rate and coke particle size were explored to ...The kinetics of coke solution loss reaction with and without sodium carbonate were investigated under the reaction atmosphere of carb on dioxide. The variables of gas flow rate and coke particle size were explored to eliminate the external and inteirial diffusion, respectively. Then, the improved method combining with the least square and the genetic algorithm was proposed to solve the homogeneous model and the shrinking core model. It was found that the improved genetic algorithm method has good stability by studying the fitness function at each generation. In the homogeneous model, the activation energy with and without sodium carbonate was 54.89 and 95.56 kJ/mol, respectively. And. the activation energy with and without sodium carbonate in the shrinking core model was 49.83 and 92.18 kJ/mol, respectively. Therefore, it was concluded that the sodium carbonate has the catalytic action. In addition, results showed that the estimated conversions were agreed well with the experimental ones, which indicated that the calculated kinetic parameters were valid and the proposed method was successfully developed.展开更多
In this work,the facile carbon nanotubes(CNTs) modulation strategy was successfully used to fabricate Bi_(5) Nb_(3) O_(15)@CNTs composites as anode materials for lithium-ion battery by a simple solid-state route.The i...In this work,the facile carbon nanotubes(CNTs) modulation strategy was successfully used to fabricate Bi_(5) Nb_(3) O_(15)@CNTs composites as anode materials for lithium-ion battery by a simple solid-state route.The introduction of CNTs does not change the structure of the Bi_(5) Nb_(3) O_(15) materials,the Bi_(5) Nb_(3) O_(15) particles are decorated on a three-dimensional CNTs network,and the high conductive network promotes transfer of electron/ion and relieve the volume change of Bi_(5) Nb_(3) O_(15).The Bi_(5) Nb_(3) O_(15)@CNTs(8 wt%) electrode shows a superior rate capability with charge(discharge) capacities of 490(898.7),379.1(401.6),311.3(326.9),276.5(285.5) and 243.4(252)mAh·g^(-1) at 50,100,200,300 and 500 mA·g^(-1),respectively.However,the Bi_(5) Nb_(3) O_(15) only shows charge(discharge) capacities of 431(772.6),278.6(309.9),193.1(213.7),160.8(171.1),129.9(139.1) mAh·g^(-1) at the corresponding rates,respectively.The excellent rate capability of Bi_(5) Nb_(3) O_(15)@CNTs can be ascribed to the homogeneous distribution of Bi_(5) Nb_(3) O_(15) particles in the CNTs conductive network and the enhancement of conductivity.Hence,the CNTs modulation can be considered as an effective strategy to enhance electrochemical performances of Bi_(5) Nb_(3) O_(15) materials.展开更多
Electrochemical reduction of molecular O2 to hydrogen peroxide(H2O2)offers a promising solution for water purification and environmental remediation.Here,we design a hierarchical free-standing single-Co-atom(with Co-N...Electrochemical reduction of molecular O2 to hydrogen peroxide(H2O2)offers a promising solution for water purification and environmental remediation.Here,we design a hierarchical free-standing single-Co-atom(with Co-N4 coordination)electrode for oxygen reduction reaction(ORR)via a two-electron pathway to make H2O2 in acidic media.The current density of the single-Co-atom electrode reached 51 mA/cm2 at 0.1 V vs reversible hydrogen electrode,lasting for more than 10 hours of continuous operation with H2O2 selectivity greater than 80%.Toward practical application,the single-Co-atom electrode was directly used to assemble an electrochemical cell to produce H2O2 at a rate of 676 mol/kgcat/h with a cell voltage of about 1.6 V.展开更多
Anisotropic SmCo5/Co nanocomposite powders have been prepared by electroless Co deposition on commercial SmCo5 powders with hydrazine as reducer. The Co particles are mainly in the range of 8–27 nm and form dense/con...Anisotropic SmCo5/Co nanocomposite powders have been prepared by electroless Co deposition on commercial SmCo5 powders with hydrazine as reducer. The Co particles are mainly in the range of 8–27 nm and form dense/continuous soft magnetic coatings on the surface of SmCo5 powders. Exchange coupling happened between the coated Co soft magnetic particles and the SmCo5 hard phase. As a result, SmCo5/Co nanocomposite powders with remanence of73.58 emu/g and energy product of 13.74 MGOe were obtained in the optimum condition, as compared with those of70.52 emu/g and 13.40 MGOe for uncoated SmCo5 powders. The effects of Co adding amount on Co particle size, coating morphology, and magnetic properties of SmCo5/Co products were investigated.展开更多
An iron(Ⅲ) cluster,namely [Fe10(μ3-O)8L8(NO3)6](1),has been synthesized by treatment of Fe(NO3)3·9 H2O with 3,5-dimethyl-l-(hydroxymethyl)-pyrazole(HL) under ambient temperature.The core skeleton of {FeⅢ10) ca...An iron(Ⅲ) cluster,namely [Fe10(μ3-O)8L8(NO3)6](1),has been synthesized by treatment of Fe(NO3)3·9 H2O with 3,5-dimethyl-l-(hydroxymethyl)-pyrazole(HL) under ambient temperature.The core skeleton of {FeⅢ10) can be regarded as a pear-like cage with eight triangular {FeⅢ3(μ3-O)} units,in which each three FeⅢ centers is held together by one μ3-O2- group with FeⅢ centers as corner-sharing triangle units.Importantly,{FeⅢ10} cluster is not only stable in solid state but also in solution,which is confirmed by powder X-ray diffraction(PXRD) pattern and electrospray ionization mass spectrometry(ESI-MS),respectively.Furthermore,1 shows anti ferromagnetic exchange behavior arising from the interactions between the iron(Ⅲ) centers.展开更多
Background The upper airway morphology in children varies with age and body position.This study aimed to analyze the impact of lateral positioning on the upper airway of sedated children under fve.Methods This retrosp...Background The upper airway morphology in children varies with age and body position.This study aimed to analyze the impact of lateral positioning on the upper airway of sedated children under fve.Methods This retrospective study included pediatric patients who underwent MRI in both the supine and lateral positions at Children’s Hospital,Zhejiang University School of Medicine.Upper airway morphology was reconstructed using 3D Slicer software.Python was employed to estimate cross-sectional areas via pixel analysis.The narrowest cross-sectional area,minimal transverse and anteroposterior diameters,airway length,and airway volume were measured and stratifed by age for subgroup analysis.Results In sedated children under 5 years old and when compared to the supine position,lateral positioning increased minimal transverse diameter by 18.70%(P=0.001),narrowest cross-sectional area by 49.21%(P<0.001),anteroposterior diameter by 25.54%(P<0.001),airway volume by 65.64%(P<0.001),and airway length by 11.93%(P<0.001).In all subgroups,lateral positioning signifcantly increased the narrowest cross-sectional area,airway length,and airway volume.However,minimal anteroposterior diameter in the 1-to 3-year age group and minimal transverse diameter in the 3-to 5-year age group tended to increase in the lateral position but did not reach statistical signifcance.Conclusions Lateral position signifcantly enlarges the upper airway in sedated children under fve.These fndings support using lateral position to enhance airway patency in younger patients.展开更多
A mixture of Pingdingshan lean coal and acid-treated Huadian oil shale was co-pyrolyzed in a drop-tube fixed-bed reactor in the temperature range of 300℃–450℃.To reveal the formation mechanism of the solid co-pyrol...A mixture of Pingdingshan lean coal and acid-treated Huadian oil shale was co-pyrolyzed in a drop-tube fixed-bed reactor in the temperature range of 300℃–450℃.To reveal the formation mechanism of the solid co-pyrolysis product,changes in some physicochemical properties were investigated,using analysis by X-ray diffraction,X-ray photoelectron spectroscopy,scanning electron microscopy,pore analysis,thermogravimetry,and electron spin resonance.X-ray diffraction showed that the lattice plane spacing for the co-pyrolyzed mixture decreased from 0.357 nm to 0.346 nm and the average stacking height increased from 1.509 nm to 1.980 nm in the temperature range of 300°C–450°C,suggesting that pyrolysis treatment increased its degree of metamorphism.The amount of oxygen-containing functional groups and pore volume decreased with increasing temperature.Thermogravimetry and electron spin resonance results showed that synergistic effects occurred during the co-pyrolysis process.A formation mechanism for the solid product was proposed.Hydrogen-rich radicals generated from the pyrolysis of the oil shale were trapped by hydrogen-poor macromolecular radicals of the intermediate metaplast produced from coal pyrolysis,thereby increasing the yield of solid product.展开更多
基金National Natural Science Foundation of China(U24A20714 to XMF and 82102238 to PC)。
文摘BACKGROUND:Tracheal intubation(TI)is a fundamental procedure for securing the airway or assisting ventilation in emergency medicine.Tracheal intubation in the lateral position(TILP)has been utilized in clinical practice,demonstrating potential advantages in specific scenarios,including emergency settings.However,there is a lack of comprehensive reviews and practical protocols on TILP application.To address this gap,we performed a narrative review,and provided evidence-based recommendations to formulate a practice protocol,to assist clinicians to effectively apply TILP.METHODS:We conducted a narrative review of TILP applications and developed recommendations based on clinical research evidence and clinical experience.Delphi method was used among the TILP consortium to grade the strength of the recommendations and to help reach consensus.The practice protocols were formulated as warranted by advancements in medical knowledge,technology,and practice.RESULTS:This narrative review summarized the current evidence on TILP application,highlighting its safety,efficacy,challenges,and potential complications.In total,24 recommendations and a clinical protocol for TILP application in emergency patients were established.CONCLUSION:TILP is a valuable technique in emergency medicine.We reviewed its application in emergency settings and formulated recommendations along with a clinical practice protocol.Future studies are needed to evaluate the safety and efficacy of TILP,broaden its scope of application,and explore effective training protocols.
基金supported by the National Natural Science Foundation of China(22278001 and 22308006)the Natural Science Foundation of Anhui Provincial Education Department(KJ2021A0407).
文摘The effects of different kinds of ionic liquids(ILs)on the caking property of Shenhua long-flame coal(SHLC)were studied.SHLC and its residue after[N_(4441)][Cl]treatment under optimum conditions were characterized by Fourier transform infrared spectroscopy(FT-IR),thermogravimetric analysis(TG),X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),Raman spectroscopy,and pyrolysis-gas chromatography and mass-spectrometric analysis(Py-GC/MS).The results showed that the ILs used could extract the poorly-caking components from SHLC,and[N_(4441)][Cl]with C_(3)H_(6)O as a solvent exhibited the best effect among the ILs and solvents used.[N_(4441)][Cl]could destroy the H bonds in SHLC,and the structure of the cross-linked macromolecules of SHLC was loosed,leading to the release of the small molecules within the macromolecular framework of SHLC.Additionally,[N_(4441)][Cl]could easily penetrate into the interior of the relaxed SHLC and break the weak covalent bonds(e.g.,C-O bonds)of the macromolecules of SHLC.As a result,aromatic hydrocarbons with 3‒5 rings and aliphatic side chains,which are the precursor of the poorly-caking components,were formed and were then extracted from SHLC by C_(3)H_(6)O.Consequently,[N_(4441)][Cl]treatment could decrease the caking property,thermal ability,and macromolecular size of SHLC.
基金supported by the National Natural Science Foundation of China(22308006 and 22278001)the Natural Science Foundation of Anhui Provincial Education Department(KJ2021A0407).
文摘Polystyrene(PS)waste was depolymerized using a low-temperature pyrolysis treatment(LTPT)to increase its caking index.The mechanism of caking index modification was revealed by using Fourier transform infrared spectroscopy,thermogravimetric(TG)analysis,pyrolysis-gas chromatography with mass spectrometric detection,and solid-state^(13)C nuclear magnetic resonance spectroscopy.The crucible coal-blending coking tests were carried out using an industrial coal mixture and the treated-PS with the highest caking index(PS300)or raw PS.Some properties of the resultant cokes were also analyzed.It was demonstrated that the caking index of PS dramatically increased by LTPT;however,exceeding 300℃ did not yield any benefit.The caking index increased due to the formation of the caking components,whose molecules are medium in size,caused by LTPT.Additionally,the coke reactivity index of the coke obtained from the mixture containing PS300 decreased by 5.1%relative to that of the coke made from the mixture with PS and the coke strength after reaction index of the former increased by 7.3% compared with that of the latter,suggesting that the ratio of depolymerized PS used for coal-blending coking could increase relative to that of PS.
基金financially supported by the Key Program for International S&T Cooperation Projects of China(No.2017YFE0124300)National Natural Science Foundation of China(No.52171205,51971002 and 52171197)+1 种基金Scientific Research Foundation of Anhui Provincial Education Department(Nos.KJ2020ZD26,KJ2021A0360)Anhui Provincial Natural Science Foundation for Excellent Youth Scholars(No.2108085Y16).
文摘Grain growth of magnesium(Mg)and its hydride is one of the main reasons for kinetic and capacity degradation during the hydrogen absorption and desorption cycles.To solve this problem,herein we propose a novel method involving synergistic effect of inside embedded metals and outside coated graphene to limit the growth of Mg and its hydride grains.The graphene coated Mg-Y-Al alloys were selected as a model system for demonstrating this positive effect where the Mg_(91)Y_(3)Al_(6)alloy was first prepared by rapidly solidified method and then high-pressure milled with 5 wt%graphene upon 5 MPa hydrogen gas for obtaining in-situ formed YAl_(2)and YH_(3)embedded in the MgH_(2)matrix with graphene shell(denoted as MgH_(2)-Y-Al@GR).In comparison to pure MgH_(2),the obtained MgH_(2)-Y-Al@GR composites deliver much better kinetics and more stable cyclic performance.For instance,the MgH_(2)-Y-Al@GR can release about 6.1 wt%H_(2)within 30 min at 300℃ but pure MgH_(2)only desorbs∼1.5 wt%H_(2).The activation energy for desorption of MgH_(2)-Y-Al@GR samples is calculated to be 75.3±9.1 kJ/mol that is much lower than approximately 160 kJ/mol for pure MgH_(2).Moreover,its capacity retention is promoted from∼57%of pure MgH_(2)to∼84%after 50th cycles without obvious particle agglomeration and grain growth.The synergistic effect of outside graphene coating with inside embedded metals which could provide a huge number of active sites for catalysis as well as inhibit the grain growth of Mg and its hydride is believed to be responsible for these.
基金supported by the National Natural Science Foundation of China(Grant Nos.22278001 and 21776002)the Natural Science Foundation of Anhui Provincial Education Department(No.KJ2021A0407)+1 种基金the Natural Science Foundation of Anhui Province(Grant No.2008085QB87)Anhui Provincial Postdoctoral Science Foundation(No.2021B538).
文摘Reducing coke use is an effective measure to reduce carbon emission and energy consumption in the blast furnace(BF)ironmaking.Essentially,BF is a high-temperature moving bed reactor,where complex physical transformations coupled with complicated reactions occur.This makes it challenging to investigate the factors determining BF performance with the conventional method.A multi-physical field coupling mathematical model of BF was thus developed to describe its mass and heat transfer as well as its intrinsic reactions.Then,the proposed model was validated with the production data.Under coupling conditions,influences of dominating reactions on BF performance(temperature distribution,gas distribution,iron formation reaction,and direct reduction degree)were revealed.The results indicated that coke combustion,indirect reduction,and direct reduction of iron ore mainly took place nearby the shaft tuyere,cohesive zone,and dripping zone,respectively.Besides,the rate of coke solution loss reaction was increased with the rising coke porosity in the cohesive zone.Considering the effect of coke porosity on the efficiency and stability of BF,the coke porosity of 0.42 was regarded as a reasonable value.
基金supported by National Natural Science Foundation of China(22478004,22078002 and 21878001)Joint Fund of the Yulin University and the Dalian National Laboratory for Clean Energy(YLU-DNL Fund 2022002)Major Project of Philosophy and Social Science Research in Anhui Universities Supported by Department of Education Anhui Province(2023AH040333).
文摘The Chinese standard method of GB/T 4000e2017 was unable to accurately measure the coke thermal properties in the large blast furnace.Therefore,the coke compressive strength(CCS)test at a high temperature was designed to examine the coke thermal properties.Then,the large-scale coke model(sp^(2)C_(17421)sp^(3)C_(6579))was established.After,the ReaxFF molecular dynamics simulations were implemented to mimic the coke solution loss(CSL)and the CCS at the high temperature.It was found that the adsorption energy and the diffusion energy of micropores were greater than those of mesopores and macropores,indicating that the CSL reaction mainly happened in the coke micropore.It was discovered that the CSL reaction mechanism was the sp^(3)C oxidization mechanism with the transient state of ketene structure.And,it was detected that the CCS process was divided into the plastic deformation,the instantaneous fracture and the elastic deformation and yield,which was caused by the local reconstruction,the overall folding and the center stretching of carbon layer,respectively.By comparing simulated results with experiments,it was proved that obtained mechanisms were valid.The proposed experimental and simulated methods provided a novel method to measure and understand the coke thermal properties.
基金supported by the Natural Science Foundation of Shandong Province,China(No.ZR2022ME079)the National Natural Science Foundation of China(Project No.52278115)the Plan of Guidance and Cultivation for Young Innovative Talents of Shandong Provincial Colleges and Universities.
文摘Abandoned mines are rich in geothermal resources.In this article,the feasibility of applying a water resource heating system in abandoned mines is explored,adopting mine water in the extraction zone as the research object.First,the utilization mode of geothermal resources in abandoned mines is introduced,and the applicable scenarios of different mine water heating methods are clarified.Second,to prevent the heat transfixion phenomenon caused by an irrational arrangement of pumping wells,a three-dimensional numerical calculation model for multiphysical field coupling of the pumping wells of a water source heat pump in abandoned mines is established,and 14 distinct types of well arrangements are simulated.According to the occurrence degree of heat transfixion,the most reasonable arrangement of pumping wells is selected.The influences of different recharge tempera-tures,pumping and recharging flow rates,well spacings,hydraulic gradients,aquifer thicknesses,porosities and other factors on the pumping temperature are studied according to the selected pumping and recharging well arrangement scheme.Finally,by choosing a residential building as the analysis object,a simulation model of the abandoned mine water source heat pump heating system is constructed,which is compared with a gas boiler heating system,revealing the energy savings and environmental protection benefits of the abandoned mine water source heat pump system.The results of this paper provide a scientific basis for the utilization of mine water geothermal resources,which can facilitate the transformation of abandoned mines and provide theoretical and technical guidance in engineering practice.
基金financial support from the National Natural Science Foundation of China(No.81673398)
文摘The development of pharmaceutical analytical methods represents one of the most significant aspects of drug development. Recent advances in microfabrication and microfluidics could provide new approaches for drug analysis, including drug screening, active testing and the study of metabolism. Microfluidic chip technologies, such as lab-on-a-chip technology, three-dimensional (3D) cell culture, organs-on-chip and droplet techniques, have all been developed rapidly. Microfluidic chips coupled with various kinds of detection techniques are suitable for the high-throughput screening, detection and mechanistic study of drugs. This review highlights the latest (2010–2018) microfluidic technology for drug analysis and discusses the potential future development in this field.
基金The authors are grateful to the National Natural Science Foundation of China(No.21776002)Natural Science Foundation of Anhui Provincial Education Department(Nos.KJ2016A097 and KJ2017A056)+1 种基金Innovation Project of Overseas People of Anhui Province,Student Research Training Program of Anhui Province(201810360190)Youth Natural Science Foundation of Anhui University of Technology(No.QZ201806)for financial support.
文摘Shenmu(SM)subbituminous coal without caking property was treated by low-temperature rapid pyrolysis(LTRP)to modify its caking and coking properties.The treated samples were characterized by Fourier transform infrared spectrometry,vitrinite reflectance,and X-ray diffraction to determine the modification mechanism.Moreover,caking index(G)and coking indices(mechanical strength,coke reactivity,and coke strength after reaction)were employed to evaluate caking and coking properties,respectively.The results showed that SM coal was gradually upgraded with increasing processing temperature.Furthermore,the G values for the treated samples were significantly higher than that for SM coal,and G reached the maximum value at 450℃,implying the modification of caking property and the existence of an optimum temperature(450℃).Additionally,laboratory coking determinations showed that LTRP increased the mechanical strength of coke and coke strength after reaction and decreased coke reactivity when the treated coals were used in the coal blends instead of raw SM coal.Overall,LTRP treatment is effective to improve the caking and coking properties of SM coal.A mechanism was proposed for the modification.Suitable upgrading degree with suitable molecular masses and some releasable hydrogen-rich donor species present within the coal,which dominate the development of caking property,is important.
基金financially supported by the National Natural Science Foundation of China(No.51774002)the Key Program for International S&T Cooperation Projects of China(No.2017YFE0124300)the“333 Talent Project”of Hebei Province(No.A202005018)。
文摘TiO_(2)-based materials have been considered as one of most promising alternatives for high-performance Li(Na)-ion batteries because of the low cost,simple composition,easy synthesis,good environmental protection,excellent safety and relatively high specific capacity.Nonetheless,the inferior electronic conductivity and poor ion diffusion coefficients are the biggest bottlenecks that restrict the popular application.Much effort has been focused on resolving these problems toward large-scale applications,and numerous significant advances have been accomplished.In the present work,a comprehensive overview of structure characteristics,electrochemical reaction mechanism and modification strategies of TiO_(2)-based materials was presented.The recent advances of various efficient ways for improving conductivity,Li(Na)storage capacity,rate capability and cycle stability are systematically summarized,including surface engineering,constructing composite and element doping,etc.Constructing TiO_(2)-based materials with novel porous heterogeneous core-shell structures have been regarded as one of the most effective ways to resolve these challenges.Finally,the future research directions and development prospects of TiO_(2)-based anode materials used in the manufacture of high-performance Li(Na)-ion batteries are prospected.This review can provide important comprehension for the construction and optimization of highperformance of TiO_(2)-based anode materials.
基金the National Natural Science Foundation of China(21476001)Key Project of Anhui Provincial Department of Education(KJ2017A045)are gratefully acknowledgedOpen Fund of Shaanxi Key Laboratory of Energy Chemical Process Intensification(No.SXECPI201601).
文摘The kinetics of coke solution loss reaction with and without sodium carbonate were investigated under the reaction atmosphere of carb on dioxide. The variables of gas flow rate and coke particle size were explored to eliminate the external and inteirial diffusion, respectively. Then, the improved method combining with the least square and the genetic algorithm was proposed to solve the homogeneous model and the shrinking core model. It was found that the improved genetic algorithm method has good stability by studying the fitness function at each generation. In the homogeneous model, the activation energy with and without sodium carbonate was 54.89 and 95.56 kJ/mol, respectively. And. the activation energy with and without sodium carbonate in the shrinking core model was 49.83 and 92.18 kJ/mol, respectively. Therefore, it was concluded that the sodium carbonate has the catalytic action. In addition, results showed that the estimated conversions were agreed well with the experimental ones, which indicated that the calculated kinetic parameters were valid and the proposed method was successfully developed.
基金financially supported by the Key Program for International S&T Cooperation Projects of China (No.2017YFE0124300)the National Natural Science Foundation of China (Nos.U1960107 and 22179019)+2 种基金the "333" Talent Project of Hebei Province (No.A202005018)the Fundamental Research Funds for the Central Universities (No.N2123001)the Natural Science Foundation of Hebei Province of China (No.B2020501003)。
文摘In this work,the facile carbon nanotubes(CNTs) modulation strategy was successfully used to fabricate Bi_(5) Nb_(3) O_(15)@CNTs composites as anode materials for lithium-ion battery by a simple solid-state route.The introduction of CNTs does not change the structure of the Bi_(5) Nb_(3) O_(15) materials,the Bi_(5) Nb_(3) O_(15) particles are decorated on a three-dimensional CNTs network,and the high conductive network promotes transfer of electron/ion and relieve the volume change of Bi_(5) Nb_(3) O_(15).The Bi_(5) Nb_(3) O_(15)@CNTs(8 wt%) electrode shows a superior rate capability with charge(discharge) capacities of 490(898.7),379.1(401.6),311.3(326.9),276.5(285.5) and 243.4(252)mAh·g^(-1) at 50,100,200,300 and 500 mA·g^(-1),respectively.However,the Bi_(5) Nb_(3) O_(15) only shows charge(discharge) capacities of 431(772.6),278.6(309.9),193.1(213.7),160.8(171.1),129.9(139.1) mAh·g^(-1) at the corresponding rates,respectively.The excellent rate capability of Bi_(5) Nb_(3) O_(15)@CNTs can be ascribed to the homogeneous distribution of Bi_(5) Nb_(3) O_(15) particles in the CNTs conductive network and the enhancement of conductivity.Hence,the CNTs modulation can be considered as an effective strategy to enhance electrochemical performances of Bi_(5) Nb_(3) O_(15) materials.
基金This study was supported by the funds from the Singapore Ministry of Education Academic Research Fund,Tier 1:RG111/15 and RG10/16 and Tier 2:MOE2016-T2-2 to 004.
文摘Electrochemical reduction of molecular O2 to hydrogen peroxide(H2O2)offers a promising solution for water purification and environmental remediation.Here,we design a hierarchical free-standing single-Co-atom(with Co-N4 coordination)electrode for oxygen reduction reaction(ORR)via a two-electron pathway to make H2O2 in acidic media.The current density of the single-Co-atom electrode reached 51 mA/cm2 at 0.1 V vs reversible hydrogen electrode,lasting for more than 10 hours of continuous operation with H2O2 selectivity greater than 80%.Toward practical application,the single-Co-atom electrode was directly used to assemble an electrochemical cell to produce H2O2 at a rate of 676 mol/kgcat/h with a cell voltage of about 1.6 V.
基金financially supported by the National Natural Science Foundation of China under Grant No. 51422106the National Basic Research Program of China under Grant No. 2014CB643702+3 种基金the Ningbo Natural Science Foundation of China under Grant No. 2016A610249the Scientific and Technological Project of Zhejiang Province under Grant No. 2013TD08the Ningbo City Scientific and Technological Project under Grant No. 2012B81001the China Postdoctoral Science Foundation under Grant No. 2016M601989 for financial support
文摘Anisotropic SmCo5/Co nanocomposite powders have been prepared by electroless Co deposition on commercial SmCo5 powders with hydrazine as reducer. The Co particles are mainly in the range of 8–27 nm and form dense/continuous soft magnetic coatings on the surface of SmCo5 powders. Exchange coupling happened between the coated Co soft magnetic particles and the SmCo5 hard phase. As a result, SmCo5/Co nanocomposite powders with remanence of73.58 emu/g and energy product of 13.74 MGOe were obtained in the optimum condition, as compared with those of70.52 emu/g and 13.40 MGOe for uncoated SmCo5 powders. The effects of Co adding amount on Co particle size, coating morphology, and magnetic properties of SmCo5/Co products were investigated.
基金financial support from the National Natural Science Foundation of China(Nos.21071188,9961105,21822107,21571115 and 21827801)the Natural Science Foundation of Shandong Province(Nos.ZR2019ZD45,JQ201803 and ZR2017MB005)+4 种基金the Key R&D Program of Shandong Procince(No.2019GSF108158)Shandong Provincial Key Laboratory of Clean Production of Fine Chemicals(No.2019FCCEKL06)the Taishan Scholar Project of Shandong Province of China(Nos.tsqn201812003 and ts20190908)the Fundamental Research Funds of Shandong University(No.2018JC046)the Slovenian Research Agency(No.P2-0348)。
文摘An iron(Ⅲ) cluster,namely [Fe10(μ3-O)8L8(NO3)6](1),has been synthesized by treatment of Fe(NO3)3·9 H2O with 3,5-dimethyl-l-(hydroxymethyl)-pyrazole(HL) under ambient temperature.The core skeleton of {FeⅢ10) can be regarded as a pear-like cage with eight triangular {FeⅢ3(μ3-O)} units,in which each three FeⅢ centers is held together by one μ3-O2- group with FeⅢ centers as corner-sharing triangle units.Importantly,{FeⅢ10} cluster is not only stable in solid state but also in solution,which is confirmed by powder X-ray diffraction(PXRD) pattern and electrospray ionization mass spectrometry(ESI-MS),respectively.Furthermore,1 shows anti ferromagnetic exchange behavior arising from the interactions between the iron(Ⅲ) centers.
基金supported by the Key Research and Development Program of Zhejiang(2022C03163 to X.F.)the National Natural Science Foundation of China(82372184 to H.L.and 82302425 to H.Y.).
文摘Background The upper airway morphology in children varies with age and body position.This study aimed to analyze the impact of lateral positioning on the upper airway of sedated children under fve.Methods This retrospective study included pediatric patients who underwent MRI in both the supine and lateral positions at Children’s Hospital,Zhejiang University School of Medicine.Upper airway morphology was reconstructed using 3D Slicer software.Python was employed to estimate cross-sectional areas via pixel analysis.The narrowest cross-sectional area,minimal transverse and anteroposterior diameters,airway length,and airway volume were measured and stratifed by age for subgroup analysis.Results In sedated children under 5 years old and when compared to the supine position,lateral positioning increased minimal transverse diameter by 18.70%(P=0.001),narrowest cross-sectional area by 49.21%(P<0.001),anteroposterior diameter by 25.54%(P<0.001),airway volume by 65.64%(P<0.001),and airway length by 11.93%(P<0.001).In all subgroups,lateral positioning signifcantly increased the narrowest cross-sectional area,airway length,and airway volume.However,minimal anteroposterior diameter in the 1-to 3-year age group and minimal transverse diameter in the 3-to 5-year age group tended to increase in the lateral position but did not reach statistical signifcance.Conclusions Lateral position signifcantly enlarges the upper airway in sedated children under fve.These fndings support using lateral position to enhance airway patency in younger patients.
基金This work was supported by the National Natural Science Foundation of China(Grant No.21776002)the Natural Science Foundation of Anhui Provincial Education Department(Grant Nos.KJ2016A097,KJ2017A056,and KJ2019A0076)+1 种基金the Innovation Project of Overseas People of Anhui Province,the Science and Technology Major Projects of Anhui Province(Grant Nos.17030901086)the Natural Science Foundation of Anhui Province(Grant Nos.1708085QB33 and 2008085QB87).
文摘A mixture of Pingdingshan lean coal and acid-treated Huadian oil shale was co-pyrolyzed in a drop-tube fixed-bed reactor in the temperature range of 300℃–450℃.To reveal the formation mechanism of the solid co-pyrolysis product,changes in some physicochemical properties were investigated,using analysis by X-ray diffraction,X-ray photoelectron spectroscopy,scanning electron microscopy,pore analysis,thermogravimetry,and electron spin resonance.X-ray diffraction showed that the lattice plane spacing for the co-pyrolyzed mixture decreased from 0.357 nm to 0.346 nm and the average stacking height increased from 1.509 nm to 1.980 nm in the temperature range of 300°C–450°C,suggesting that pyrolysis treatment increased its degree of metamorphism.The amount of oxygen-containing functional groups and pore volume decreased with increasing temperature.Thermogravimetry and electron spin resonance results showed that synergistic effects occurred during the co-pyrolysis process.A formation mechanism for the solid product was proposed.Hydrogen-rich radicals generated from the pyrolysis of the oil shale were trapped by hydrogen-poor macromolecular radicals of the intermediate metaplast produced from coal pyrolysis,thereby increasing the yield of solid product.
