Al80Ni6 Y8 Co4 Cu2 amorphous ribbons were isothermally annealed and a mixed structure consisting of α-Al particle with a size of less than 15nm and Al3Ni compound with a size of about 30nm was obtained. The crystall...Al80Ni6 Y8 Co4 Cu2 amorphous ribbons were isothermally annealed and a mixed structure consisting of α-Al particle with a size of less than 15nm and Al3Ni compound with a size of about 30nm was obtained. The crystallization kinetics of Al80Ni6 Y8 Co4 Cu2 amorphous alloy shows that the precipitation of α-Al particles is the growth process controlled by diffusion of the solute elements rejected from the growing crystals. By quenching at different cooling rates, a mixed structure consisting of nanoscale α-Al particles and the remaining glass matrix or structure consisting of nanoscale particle (Al phase or Al3Ni compound) with a size of about 100nm was formed. The addition of Co elements and Cu elements to Al-Ni-Y alloy systems increases the glass formation ability of the alloy and the thermal stability of the supercooled liquid region against crystallization, which results from significant difference of atomic size, strong bonding nature among constituent elements and the low diffisivity of the solute elements due to the concentration gradient in the growing front of crystals.展开更多
The slippery liquid-infused porous surfaces inspired by the microstructure of carnivorous nepenthes have aroused widespread attention,which show stable liquid repellency,glorious self-repairing powers and effective an...The slippery liquid-infused porous surfaces inspired by the microstructure of carnivorous nepenthes have aroused widespread attention,which show stable liquid repellency,glorious self-repairing powers and effective anti-fouling properties.The surfaces are manufactured via the infusion of lubricant oil into porous structures,a process which allows other fluids to slide off the interfaces readily.However,the practical applications of slippery liquid-infused surfaces are limited to the complicated preparation processes and poor oil lock ability.We aim to,in this review,present the fundamental theories of the slippery liquid-infused porous surface.Some typical natural examples are clarified while representative fabricating methods such as liquid flame spray,layer-by-layer assembly,lithography and so on are listed.The slippery surface can facilitate the manufacture of transparent and multi-functional slippery materials by means of straightforward procedures.The slippery liquid-infused porous surfaces were applied in hot water repellency,anti-fouling,ice-phobic,water condensation,control of underwater bubble transport and drag reduction.This article discusses all these issues along with emerging applications as well as future challenges.展开更多
Nanoscale hierarchically porous metal–organic frameworks(NHP-MOFs)have received unprecedented attention in many fields owing to their integration of the strengths of nanoscale size(<1μm)and hierarchical porous st...Nanoscale hierarchically porous metal–organic frameworks(NHP-MOFs)have received unprecedented attention in many fields owing to their integration of the strengths of nanoscale size(<1μm)and hierarchical porous structure(micro-,meso-and/or macro-pores)of MOFs.This review focuses on recent advances in the main synthetic strategies for NHP-MOFs based on different metal ions(e.g.,Cu,Fe,Co,Zn,Al,Zr,and Cr),including the template method,composite technology,post-synthetic modification,in situ growth and the grind method.In addition,the mechanisms of synthesis,regulation techniques and the advantages and disadvantages of various methods are discussed.Finally,the challenges and prospects of the commercialisation of promising NHP-MOFs are also presented.The purpose of this review is to provide a road map for future design and development of NHP-MOFs for practical application.展开更多
The latest researches reveal that studies on unconventional clastic oil reservoirs in China generally lag far behind those in other countries in respect of content and methodology.This study presents the definition an...The latest researches reveal that studies on unconventional clastic oil reservoirs in China generally lag far behind those in other countries in respect of content and methodology.This study presents the definition and classification of unconventional oil reservoirs and analyzes the problems in the fine description of unconventional oil reservoirs.The key content of the fine description of unconventional oil reservoirs is summarized from four aspects:fine fracture characterization based on fine structure interpretation,reservoir architecture characterization based on sedimentary facies,characteristics of nanoscale microscopic pore structure of reservoir,and evaluation of source rock and“sweet spot zone”.Finally,this study suggests that development of fine description of unconventional clastic oil reservoirs in the future should focus on rock brittleness analysis and fracture modeling,geophysical characterization of unconventional clastic oil reservoirs,fluid description of tight reservoirs,and physical/numerical simulation experiments of unconventional oil reservoirs.展开更多
Centrifugal and shear forces are produced when solids or liquids rotate.Rotary systems and devices that use these forces,such as dynamic thin-film flow technology,are evolving continuously,improve material structure-p...Centrifugal and shear forces are produced when solids or liquids rotate.Rotary systems and devices that use these forces,such as dynamic thin-film flow technology,are evolving continuously,improve material structure-property relationships at the nanoscale,representing a rapidly thriving and expanding field of research high with green chemistry metrics,consolidated at the inception of science.The vortex fluidic device(VFD)provides many advantages over conventional batch processing,with fluidic waves causing high shear and producing large surface areas for micro-mixing as well as rapid mass and heat transfer,enabling reactions beyond diffusion control.Combining these abilities allows for a green and innovative approach to altering materials for various research and industry applications by controlling small-scale flows and regulating molecular and macromolecular chemical reactivity,self-organization phenomena,and the synthesis of novel materials.This review highlights the aptitude of the VFD as clean technology,with an increase in efficiency for a diversity of top-down,bottom-up,and novel material transformations which benefit from effective vortex-based processing to control material structure-property relationships.展开更多
将聚焦离子束和扫描电子显微镜相整合而形成的双束系统——聚焦离子束扫描电子显微镜(Focused Ion Beam-Scanning Electron Microscopy,FIB-SEM)已成为对生物样品的超微结构进行成像和定量分析的有力工具。该系统既能对硬质生物材料进...将聚焦离子束和扫描电子显微镜相整合而形成的双束系统——聚焦离子束扫描电子显微镜(Focused Ion Beam-Scanning Electron Microscopy,FIB-SEM)已成为对生物样品的超微结构进行成像和定量分析的有力工具。该系统既能对硬质生物材料进行铣削,又能在纳米尺度完成对其三维结构的重建。更为重要的是,它还能将组织或器官的宏观形态与组成细胞的内部结构直接关联。本文介绍了FIB-SEM的工作原理和设备组成,对FIB-SEM三维成像在肿瘤及肿瘤干细胞模型、生物打印系统的铣削、成像和超微结构分析,以及癌细胞对纳米颗粒的摄入等肿瘤生物学领域的典型应用进行了概述,并对利用FIB-SEM三维定量和超微结构分析的方法研究线粒体和其他亚细胞结构与癌症发生的关系提出了展望。目的是强化FIB-SEM在肿瘤生物学领域的应用,以揭示肿瘤细胞超微形态和结构变化对肿瘤演进所起的作用,为肿瘤治疗提供新靶标。展开更多
A radial basis function collocation method based on the nonlocal elastic continuum theory is developed to compute the band structures of nanoscale multilayered phononic crystals. The effects of nonlocal imperfect inte...A radial basis function collocation method based on the nonlocal elastic continuum theory is developed to compute the band structures of nanoscale multilayered phononic crystals. The effects of nonlocal imperfect interfaces on band structures of transverse waves propagating obliquely or vertically in the system are studied. The correctness of the present method is verified by comparing the numerical results with those obtained by applying the transfer matrix method in the case of nonlocal perfect interface. Furthermore, the influences of the nanoscale size, the impedance ratio and the incident angle on the cut-off frequency and band structures are investigated and discussed in detail. Numerical results show that the nonlocal interface imperfections have significant effects on the band structures in the macroscopic and microscopic scale.展开更多
The development of a simple and facile synthesis route is a highly desirable but challenging process in the fabrication of nanoscale hierarchical porous zeolitic imidazolate frameworks(ZIFs).Herein we describe a facil...The development of a simple and facile synthesis route is a highly desirable but challenging process in the fabrication of nanoscale hierarchical porous zeolitic imidazolate frameworks(ZIFs).Herein we describe a facile method for rapidly synthesizing hierarchically porous ZIF-90 nanocrystals(particle sizes of~300 nm)using hydroxyl double salts as intermediates at room temperature.The as-synthesized ZIF-90 contained hierarchical porous structures developed using a crystalline interior and a random stack of multiple nanoparticles.Both the morphology and particle size of ZIF-90 nanocrystals could be tuned by controlling the molar ratio of ICA/Zn^(2+).Note that the as-synthesized hierarchically porous ZIF-90 nanocrystals exhibited higher thermal stability compared with the conventional ZIF-90.Because of the introduction of hierarchical porous structures,the resultant hierarchically porous ZIF-90 nanocrystals showed enhanced toluene adsorption capacity than those of conventional metal organic frameworks and zeolites.展开更多
以煤加工副产物煤焦油中蒽油馏分为碳源、多巴胺为氮源,基于纳米碳酸钙球模板在碳化过程中发生的诱导自活化作用,一步共碳化制得氮掺杂多孔碳(NPCs)材料。通过元素分析、低温氮气吸附-脱附测试、扫描及透射电镜表征,结果表明,NPCs材料...以煤加工副产物煤焦油中蒽油馏分为碳源、多巴胺为氮源,基于纳米碳酸钙球模板在碳化过程中发生的诱导自活化作用,一步共碳化制得氮掺杂多孔碳(NPCs)材料。通过元素分析、低温氮气吸附-脱附测试、扫描及透射电镜表征,结果表明,NPCs材料的氮元素掺杂量高,且具有发达的微孔-介孔梯级孔道结构。结合室温下催化硫化氢选择性氧化为单质硫的反应性能评价,发现改变模板剂用量、碳/氮源投料比和碳化温度,可调控NPCs材料的氮掺杂量(质量分数6.4%~21.3%)、比表面积、孔道结构发达程度及相应的定向转化硫容,最佳工艺条件下合成样品的饱和硫容高达5.8 g H2S/(g催化剂)。展开更多
A variety of intermetallic compounds in the binary Sm Co system were reviewed, and the contents were focused on the crystal structures, magnetic properties and the nanoscale effects. The representative nanocrystalline...A variety of intermetallic compounds in the binary Sm Co system were reviewed, and the contents were focused on the crystal structures, magnetic properties and the nanoscale effects. The representative nanocrystalline Sm-Co compounds were introduced in details, the diagrams for their lattice structures and the atomic sites and occupancies were provided. Moreover, the magnetic properties of the nanocrystalline Sm-Co compounds were compared with those of the conventional polycrystalline counterparts. It showed that the nanocrystalline Sm Co compounds exhibit special phase stability and remarkably enhanced magnetic performance, which are promising candidates for the matrix phases to develop permanent magnets, particularly the advanced high-temperature magnetic materials.展开更多
文摘Al80Ni6 Y8 Co4 Cu2 amorphous ribbons were isothermally annealed and a mixed structure consisting of α-Al particle with a size of less than 15nm and Al3Ni compound with a size of about 30nm was obtained. The crystallization kinetics of Al80Ni6 Y8 Co4 Cu2 amorphous alloy shows that the precipitation of α-Al particles is the growth process controlled by diffusion of the solute elements rejected from the growing crystals. By quenching at different cooling rates, a mixed structure consisting of nanoscale α-Al particles and the remaining glass matrix or structure consisting of nanoscale particle (Al phase or Al3Ni compound) with a size of about 100nm was formed. The addition of Co elements and Cu elements to Al-Ni-Y alloy systems increases the glass formation ability of the alloy and the thermal stability of the supercooled liquid region against crystallization, which results from significant difference of atomic size, strong bonding nature among constituent elements and the low diffisivity of the solute elements due to the concentration gradient in the growing front of crystals.
基金This work is supported by the National Nature Science Foundation of China(NO 51675513 and 51735013).
文摘The slippery liquid-infused porous surfaces inspired by the microstructure of carnivorous nepenthes have aroused widespread attention,which show stable liquid repellency,glorious self-repairing powers and effective anti-fouling properties.The surfaces are manufactured via the infusion of lubricant oil into porous structures,a process which allows other fluids to slide off the interfaces readily.However,the practical applications of slippery liquid-infused surfaces are limited to the complicated preparation processes and poor oil lock ability.We aim to,in this review,present the fundamental theories of the slippery liquid-infused porous surface.Some typical natural examples are clarified while representative fabricating methods such as liquid flame spray,layer-by-layer assembly,lithography and so on are listed.The slippery surface can facilitate the manufacture of transparent and multi-functional slippery materials by means of straightforward procedures.The slippery liquid-infused porous surfaces were applied in hot water repellency,anti-fouling,ice-phobic,water condensation,control of underwater bubble transport and drag reduction.This article discusses all these issues along with emerging applications as well as future challenges.
基金the financial support from the National Natural Science Foundation of China(22008032,22108034,and 22102026)the Guangdong Basic and Applied Basic Research Foundation(2019A1515110706)+2 种基金the Guangdong Provincial Key Lab of Green Chemical Product Technology(GC202111)the Medical Science and Technology Research Foundation of Guangdong Province(A2021189)the Shandong Provincial Natural Science Foundation(ZR2018ZC1458)。
文摘Nanoscale hierarchically porous metal–organic frameworks(NHP-MOFs)have received unprecedented attention in many fields owing to their integration of the strengths of nanoscale size(<1μm)and hierarchical porous structure(micro-,meso-and/or macro-pores)of MOFs.This review focuses on recent advances in the main synthetic strategies for NHP-MOFs based on different metal ions(e.g.,Cu,Fe,Co,Zn,Al,Zr,and Cr),including the template method,composite technology,post-synthetic modification,in situ growth and the grind method.In addition,the mechanisms of synthesis,regulation techniques and the advantages and disadvantages of various methods are discussed.Finally,the challenges and prospects of the commercialisation of promising NHP-MOFs are also presented.The purpose of this review is to provide a road map for future design and development of NHP-MOFs for practical application.
文摘The latest researches reveal that studies on unconventional clastic oil reservoirs in China generally lag far behind those in other countries in respect of content and methodology.This study presents the definition and classification of unconventional oil reservoirs and analyzes the problems in the fine description of unconventional oil reservoirs.The key content of the fine description of unconventional oil reservoirs is summarized from four aspects:fine fracture characterization based on fine structure interpretation,reservoir architecture characterization based on sedimentary facies,characteristics of nanoscale microscopic pore structure of reservoir,and evaluation of source rock and“sweet spot zone”.Finally,this study suggests that development of fine description of unconventional clastic oil reservoirs in the future should focus on rock brittleness analysis and fracture modeling,geophysical characterization of unconventional clastic oil reservoirs,fluid description of tight reservoirs,and physical/numerical simulation experiments of unconventional oil reservoirs.
基金Postgraduate Research Scholarship and Flinders University Research Investment Fund 2022,and the Australian Research Council,Grant/Award Numbers:DP200101105,DP200101106。
文摘Centrifugal and shear forces are produced when solids or liquids rotate.Rotary systems and devices that use these forces,such as dynamic thin-film flow technology,are evolving continuously,improve material structure-property relationships at the nanoscale,representing a rapidly thriving and expanding field of research high with green chemistry metrics,consolidated at the inception of science.The vortex fluidic device(VFD)provides many advantages over conventional batch processing,with fluidic waves causing high shear and producing large surface areas for micro-mixing as well as rapid mass and heat transfer,enabling reactions beyond diffusion control.Combining these abilities allows for a green and innovative approach to altering materials for various research and industry applications by controlling small-scale flows and regulating molecular and macromolecular chemical reactivity,self-organization phenomena,and the synthesis of novel materials.This review highlights the aptitude of the VFD as clean technology,with an increase in efficiency for a diversity of top-down,bottom-up,and novel material transformations which benefit from effective vortex-based processing to control material structure-property relationships.
文摘将聚焦离子束和扫描电子显微镜相整合而形成的双束系统——聚焦离子束扫描电子显微镜(Focused Ion Beam-Scanning Electron Microscopy,FIB-SEM)已成为对生物样品的超微结构进行成像和定量分析的有力工具。该系统既能对硬质生物材料进行铣削,又能在纳米尺度完成对其三维结构的重建。更为重要的是,它还能将组织或器官的宏观形态与组成细胞的内部结构直接关联。本文介绍了FIB-SEM的工作原理和设备组成,对FIB-SEM三维成像在肿瘤及肿瘤干细胞模型、生物打印系统的铣削、成像和超微结构分析,以及癌细胞对纳米颗粒的摄入等肿瘤生物学领域的典型应用进行了概述,并对利用FIB-SEM三维定量和超微结构分析的方法研究线粒体和其他亚细胞结构与癌症发生的关系提出了展望。目的是强化FIB-SEM在肿瘤生物学领域的应用,以揭示肿瘤细胞超微形态和结构变化对肿瘤演进所起的作用,为肿瘤治疗提供新靶标。
基金supports by the National Natural Science Foundation of China (Grants 11002026, 11372039)the Beijing Natural Science Foundation (Grant 3133039)the Scientific Research Foundation for the Returned (Grant 20121832001)
文摘A radial basis function collocation method based on the nonlocal elastic continuum theory is developed to compute the band structures of nanoscale multilayered phononic crystals. The effects of nonlocal imperfect interfaces on band structures of transverse waves propagating obliquely or vertically in the system are studied. The correctness of the present method is verified by comparing the numerical results with those obtained by applying the transfer matrix method in the case of nonlocal perfect interface. Furthermore, the influences of the nanoscale size, the impedance ratio and the incident angle on the cut-off frequency and band structures are investigated and discussed in detail. Numerical results show that the nonlocal interface imperfections have significant effects on the band structures in the macroscopic and microscopic scale.
基金the National Natural Science Foundation of China(No.21576094)the Guangdong Natural Science Foundation(No.2017A030313052)the Guangdong Basic and Applied Basic Research Foundation(Nos.2019A1515110706,2019A1515110259 and 2019A1515110535)。
文摘The development of a simple and facile synthesis route is a highly desirable but challenging process in the fabrication of nanoscale hierarchical porous zeolitic imidazolate frameworks(ZIFs).Herein we describe a facile method for rapidly synthesizing hierarchically porous ZIF-90 nanocrystals(particle sizes of~300 nm)using hydroxyl double salts as intermediates at room temperature.The as-synthesized ZIF-90 contained hierarchical porous structures developed using a crystalline interior and a random stack of multiple nanoparticles.Both the morphology and particle size of ZIF-90 nanocrystals could be tuned by controlling the molar ratio of ICA/Zn^(2+).Note that the as-synthesized hierarchically porous ZIF-90 nanocrystals exhibited higher thermal stability compared with the conventional ZIF-90.Because of the introduction of hierarchical porous structures,the resultant hierarchically porous ZIF-90 nanocrystals showed enhanced toluene adsorption capacity than those of conventional metal organic frameworks and zeolites.
文摘以煤加工副产物煤焦油中蒽油馏分为碳源、多巴胺为氮源,基于纳米碳酸钙球模板在碳化过程中发生的诱导自活化作用,一步共碳化制得氮掺杂多孔碳(NPCs)材料。通过元素分析、低温氮气吸附-脱附测试、扫描及透射电镜表征,结果表明,NPCs材料的氮元素掺杂量高,且具有发达的微孔-介孔梯级孔道结构。结合室温下催化硫化氢选择性氧化为单质硫的反应性能评价,发现改变模板剂用量、碳/氮源投料比和碳化温度,可调控NPCs材料的氮掺杂量(质量分数6.4%~21.3%)、比表面积、孔道结构发达程度及相应的定向转化硫容,最佳工艺条件下合成样品的饱和硫容高达5.8 g H2S/(g催化剂)。
文摘A variety of intermetallic compounds in the binary Sm Co system were reviewed, and the contents were focused on the crystal structures, magnetic properties and the nanoscale effects. The representative nanocrystalline Sm-Co compounds were introduced in details, the diagrams for their lattice structures and the atomic sites and occupancies were provided. Moreover, the magnetic properties of the nanocrystalline Sm-Co compounds were compared with those of the conventional polycrystalline counterparts. It showed that the nanocrystalline Sm Co compounds exhibit special phase stability and remarkably enhanced magnetic performance, which are promising candidates for the matrix phases to develop permanent magnets, particularly the advanced high-temperature magnetic materials.
