To study the effects of bubbles (or cavities) collapse on a solid surface, a rotating disk device was used here to create bubbles (or bubbles) in water. In the apparatus, these bubbles are led to collapse on the surfa...To study the effects of bubbles (or cavities) collapse on a solid surface, a rotating disk device was used here to create bubbles (or bubbles) in water. In the apparatus, these bubbles are led to collapse on the surface of carbon steel (commonly used in structures and machine impellers), and so related to higher costs for the hydraulic machines industry when damaged by such phenomenon, for example. After that, the specimens are observed with the aid of a scanning electronic microscope, where the damages on the specimens are analyzed showing pits and approximate circular areas on their surfaces. An explanation is presented here, based on collapse simulations (for qualitative purposes) and their result using images of the specimens after the collapses to visualize the damages caused by prints on their surface. The pits are certainly made by liquid micro-jet impingement while the areas, showing some aspects of burning, are credited to the high temperature impaction of the bubble contents in the final stages of its collapse.展开更多
Masquerade culture is an essential part of Sekondi-Takoradi cultural embodiment. The masquerade festival titled Ankos displays interesting costumes that have artistic elements of potent colour display and performances...Masquerade culture is an essential part of Sekondi-Takoradi cultural embodiment. The masquerade festival titled Ankos displays interesting costumes that have artistic elements of potent colour display and performances. The masquerade costumes manifest intricate fabric decoration techniques for example pleating, folding, gathering, smocking, hand and machine stitching and the use of varied colour schemes. These decorative techniques make costume production laborious, tedious and downtime constraints. In contributing to the innovative approaches to creating textile designs and prints, the study explored the inspirational possibilities of surface designs of the masquerade costume for textile designs and prints. The art-based research design and direct observation as research instrumentation were employed in the artistic creation for the study. Adobe Photoshop was used in the simulation design processes. The study revealed that the simulation design processes produced an innovative imitated visual appearance of the masquerade costume and production processes from a machine-stitched work to a hand-printed fabric. It is recommended that costume makers adopt the contemporary possibility of using hand screen to print hitherto the traditional laborious and tedious process of producing masquerade costumes.展开更多
This paper is about New-Year woodcut prints done in the Taohuawu area of Suzhou in the Chinese Ming and Qing periods that influenced Edo period ukiyo-e.And Japanese ukiyo-e impacted Western Post-Impressionism.The subj...This paper is about New-Year woodcut prints done in the Taohuawu area of Suzhou in the Chinese Ming and Qing periods that influenced Edo period ukiyo-e.And Japanese ukiyo-e impacted Western Post-Impressionism.The subject matters of Taohuawu en gravings came from Chinese folk life,and were highly decorative.The engravings were reasonably inexpensive for ordinary people.This art form influenced ukiyo-e directly.As a Japanese engraving expert wrote:"Chinese prints were a good model for Japanese engravings.Chi nese New-Year engravings moved Japanese ukiyo-e artists so much that the new idea of ukiyo-e was influenced largely by them."[1]展开更多
The article discusses fingerprints,which are the unique patterns of friction ridges found on the fingers and palms of hands.Fingerprints are highly valued as evidence in a court of law due to their uniqueness.Powder d...The article discusses fingerprints,which are the unique patterns of friction ridges found on the fingers and palms of hands.Fingerprints are highly valued as evidence in a court of law due to their uniqueness.Powder dusting is a common method for developing fingerprints on various surfaces,which involves applying finely formulated powders to the fingermark impression with a camel hairbrush.This work proposes the use of organic household materials such as water chestnut(Singhara flour)to develop powders for latent fingerprint development,which adhere to sweat and moisture on the surface of fingers,palms,and soles.The powder formulation sticks to the ridges,and the excess powder is blown away,resulting in multicolored patterns that provide an excellent outcome.The objective of the study is to offer an alternative to conventional,expensive,and toxic laboratory powders.These organic powders are eco‑friendly,cost‑effective,nontoxic,and readily available for use in crime scenes and future applications.展开更多
Refractory metals,including tungsten(W),tantalum(Ta),molybdenum(Mo),and niobium(Nb),play a vital role in industries,such as nuclear energy and aerospace,owing to their exceptional melting temperatures,thermal durabili...Refractory metals,including tungsten(W),tantalum(Ta),molybdenum(Mo),and niobium(Nb),play a vital role in industries,such as nuclear energy and aerospace,owing to their exceptional melting temperatures,thermal durability,and corrosion resistance.These metals have body-centered cubic crystal structure,characterized by limited slip systems and impeded dislocation motion,resulting in significant low-temperature brittleness,which poses challenges for the conventional processing.Additive manufacturing technique provides an innovative approach,enabling the production of intricate parts without molds,which significantly improves the efficiency of material usage.This review provides a comprehensive overview of the advancements in additive manufacturing techniques for the production of refractory metals,such as W,Ta,Mo,and Nb,particularly the laser powder bed fusion.In this review,the influence mechanisms of key process parameters(laser power,scan strategy,and powder characteristics)on the evolution of material microstructure,the formation of metallurgical defects,and mechanical properties were discussed.Generally,optimizing powder characteristics,such as sphericity,implementing substrate preheating,and formulating alloying strategies can significantly improve the densification and crack resistance of manufactured parts.Meanwhile,strictly controlling the oxygen impurity content and optimizing the energy density input are also the key factors to achieve the simultaneous improvement in strength and ductility of refractory metals.Although additive manufacturing technique provides an innovative solution for processing refractory metals,critical issues,such as residual stress control,microstructure and performance anisotropy,and process stability,still need to be addressed.This review not only provides a theoretical basis for the additive manufacturing of high-performance refractory metals,but also proposes forward-looking directions for their industrial application.展开更多
A Novel Dosimetry Method for Small Animal Irradiators Using 3D-printed Mouse Phantoms and Alanine Dosimeters.Christopher Duncan1,Chad Gunther1(1.C&C Irradiator Service,LLC,Washington,DC,20006.)Abstract:Accurate do...A Novel Dosimetry Method for Small Animal Irradiators Using 3D-printed Mouse Phantoms and Alanine Dosimeters.Christopher Duncan1,Chad Gunther1(1.C&C Irradiator Service,LLC,Washington,DC,20006.)Abstract:Accurate dosimetry is a crucial component of small animal and preclinical irradiation studies.展开更多
Aerogels are ultra-lightweight,porous materials defined by a complex network of interconnected pores and nanostructures,which effectively suppress heat transfer,making them exceptional for thermal insulation.Furthermo...Aerogels are ultra-lightweight,porous materials defined by a complex network of interconnected pores and nanostructures,which effectively suppress heat transfer,making them exceptional for thermal insulation.Furthermore,their porous architecture can trap and scatter light via multiple internal reflections,extending the optical path within the material.When combined with suitable light-absorbing materials,this feature significantly enhances light absorption(darkness).To validate this concept,mesoporous silica aerogel particles were incorporated into a resorcinol-formaldehyde(RF)sol,and the silica-to-RF ratio was optimized to achieve uniform carbon compound coatings on the silica pore walls.Notably,increasing silica loading raised the sol viscosity,enabling formulations ideal for direct ink writing processes with excellent shape fidelity for super-black topographical designs.The printed silica-RF green bodies exhibited remarkable mechanical strength and ultra-low thermal conductivity(15.8 m W m^(-1) K^(-1))prior to pyrolysis.Following pyrolysis,the composites maintained structural integrity and printed microcellular geometries while achieving super-black coloration(abs.99.56%in the 280-2500 nm range)and high photothermal conversion efficiency(94.2%).Additionally,these silica-carbon aerogel microcellulars demonstrated stable electrical conductivity and low electrochemical impedance.The synergistic combination of 3D printability and super-black photothermal features makes these composites highly versatile for multifunctional applications,including on-demand thermal management,and efficient solar-driven water production.展开更多
In the realm of secure information storage,optical encryption has emerged as a vital technique,particularly with the miniaturization of encryption devices.However,many existing systems lack the necessary reconfigurabi...In the realm of secure information storage,optical encryption has emerged as a vital technique,particularly with the miniaturization of encryption devices.However,many existing systems lack the necessary reconfigurability and dynamic functionality.This study presents a novel approach through the development of dynamic optical-to-chemical energy conversion metamaterials,which enable enhanced steganography and multilevel information storage.We introduce a micro-dynamic multiple encryption device that leverages programmable optical properties in coumarin-based metamaterials,achieved through a direct laser writing grayscale gradient strategy.This methodology allows for the dynamic regulation of photoluminescent characteristics and cross-linking networks,facilitating innovative steganographic techniques under varying light conditions.The integration of a multi-optical field control system enables real-time adjustments to the material’s properties,enhancing the device’s reconfigurability and storage capabilities.Our findings underscore the potential of these metamaterials in advancing the field of microscale optical encryption,paving the way for future applications in dynamic storage and information security.展开更多
3D printing,as a versatile additive manufacturing technique,offers high design flexibility,rapid prototyping,minimal material waste,and the capability to fabricate complex,customized geometries.These attributes make i...3D printing,as a versatile additive manufacturing technique,offers high design flexibility,rapid prototyping,minimal material waste,and the capability to fabricate complex,customized geometries.These attributes make it particularly well-suited for low-temperature hydrogen electrochemical conversion devices—specifically,proton exchange membrane fuel cells,proton exchange membrane electrolyzer cells,anion exchange membrane electrolyzer cells,and alkaline electrolyzers—which demand finely structured components such as catalyst layers,gas diffusion layers,electrodes,porous transport layers,and bipolar plates.This review provides a focused and critical summary of the current progress in applying 3D printing technologies to these key components.It begins with a concise introduction to the principles and classifications of mainstream 3D printing methods relevant to the hydrogen energy sector and proceeds to analyze their specific applications and performance impacts across different device architectures.Finally,the review identifies existing technical challenges and outlines future research directions to accelerate the integration of 3D printing in nextgeneration low-temperature hydrogen energy systems.展开更多
In this study,the design,analysis,manufacturing,and testing of a 3D-printed conformal microstrip array antenna for high-temperature environments is presented.3D printing technology is used to fabricate a curved cerami...In this study,the design,analysis,manufacturing,and testing of a 3D-printed conformal microstrip array antenna for high-temperature environments is presented.3D printing technology is used to fabricate a curved ceramic substrate,and laser sintering and microdroplet spraying processes are used to add the conductive metal on the curved substrate.The problems of gain loss,bandwidth reduction,and frequency shift caused by high temperatures are addressed by using a proper antenna design,with parasitic patches,slots,and metal resonant cavities.The antenna prototype is characterized by the curved substrates and the conductive metals for the power dividers,the patch,and the ground plane;its performance is examined up to a temperature of 600℃in a muffle furnace and compared with the results from the numerical analysis.The results show that the antenna can effectively function at 600℃and even higher temperatures.展开更多
文摘To study the effects of bubbles (or cavities) collapse on a solid surface, a rotating disk device was used here to create bubbles (or bubbles) in water. In the apparatus, these bubbles are led to collapse on the surface of carbon steel (commonly used in structures and machine impellers), and so related to higher costs for the hydraulic machines industry when damaged by such phenomenon, for example. After that, the specimens are observed with the aid of a scanning electronic microscope, where the damages on the specimens are analyzed showing pits and approximate circular areas on their surfaces. An explanation is presented here, based on collapse simulations (for qualitative purposes) and their result using images of the specimens after the collapses to visualize the damages caused by prints on their surface. The pits are certainly made by liquid micro-jet impingement while the areas, showing some aspects of burning, are credited to the high temperature impaction of the bubble contents in the final stages of its collapse.
文摘Masquerade culture is an essential part of Sekondi-Takoradi cultural embodiment. The masquerade festival titled Ankos displays interesting costumes that have artistic elements of potent colour display and performances. The masquerade costumes manifest intricate fabric decoration techniques for example pleating, folding, gathering, smocking, hand and machine stitching and the use of varied colour schemes. These decorative techniques make costume production laborious, tedious and downtime constraints. In contributing to the innovative approaches to creating textile designs and prints, the study explored the inspirational possibilities of surface designs of the masquerade costume for textile designs and prints. The art-based research design and direct observation as research instrumentation were employed in the artistic creation for the study. Adobe Photoshop was used in the simulation design processes. The study revealed that the simulation design processes produced an innovative imitated visual appearance of the masquerade costume and production processes from a machine-stitched work to a hand-printed fabric. It is recommended that costume makers adopt the contemporary possibility of using hand screen to print hitherto the traditional laborious and tedious process of producing masquerade costumes.
文摘This paper is about New-Year woodcut prints done in the Taohuawu area of Suzhou in the Chinese Ming and Qing periods that influenced Edo period ukiyo-e.And Japanese ukiyo-e impacted Western Post-Impressionism.The subject matters of Taohuawu en gravings came from Chinese folk life,and were highly decorative.The engravings were reasonably inexpensive for ordinary people.This art form influenced ukiyo-e directly.As a Japanese engraving expert wrote:"Chinese prints were a good model for Japanese engravings.Chi nese New-Year engravings moved Japanese ukiyo-e artists so much that the new idea of ukiyo-e was influenced largely by them."[1]
文摘The article discusses fingerprints,which are the unique patterns of friction ridges found on the fingers and palms of hands.Fingerprints are highly valued as evidence in a court of law due to their uniqueness.Powder dusting is a common method for developing fingerprints on various surfaces,which involves applying finely formulated powders to the fingermark impression with a camel hairbrush.This work proposes the use of organic household materials such as water chestnut(Singhara flour)to develop powders for latent fingerprint development,which adhere to sweat and moisture on the surface of fingers,palms,and soles.The powder formulation sticks to the ridges,and the excess powder is blown away,resulting in multicolored patterns that provide an excellent outcome.The objective of the study is to offer an alternative to conventional,expensive,and toxic laboratory powders.These organic powders are eco‑friendly,cost‑effective,nontoxic,and readily available for use in crime scenes and future applications.
基金National MCF Energy R&D Program(2024YFE03260300)。
文摘Refractory metals,including tungsten(W),tantalum(Ta),molybdenum(Mo),and niobium(Nb),play a vital role in industries,such as nuclear energy and aerospace,owing to their exceptional melting temperatures,thermal durability,and corrosion resistance.These metals have body-centered cubic crystal structure,characterized by limited slip systems and impeded dislocation motion,resulting in significant low-temperature brittleness,which poses challenges for the conventional processing.Additive manufacturing technique provides an innovative approach,enabling the production of intricate parts without molds,which significantly improves the efficiency of material usage.This review provides a comprehensive overview of the advancements in additive manufacturing techniques for the production of refractory metals,such as W,Ta,Mo,and Nb,particularly the laser powder bed fusion.In this review,the influence mechanisms of key process parameters(laser power,scan strategy,and powder characteristics)on the evolution of material microstructure,the formation of metallurgical defects,and mechanical properties were discussed.Generally,optimizing powder characteristics,such as sphericity,implementing substrate preheating,and formulating alloying strategies can significantly improve the densification and crack resistance of manufactured parts.Meanwhile,strictly controlling the oxygen impurity content and optimizing the energy density input are also the key factors to achieve the simultaneous improvement in strength and ductility of refractory metals.Although additive manufacturing technique provides an innovative solution for processing refractory metals,critical issues,such as residual stress control,microstructure and performance anisotropy,and process stability,still need to be addressed.This review not only provides a theoretical basis for the additive manufacturing of high-performance refractory metals,but also proposes forward-looking directions for their industrial application.
文摘A Novel Dosimetry Method for Small Animal Irradiators Using 3D-printed Mouse Phantoms and Alanine Dosimeters.Christopher Duncan1,Chad Gunther1(1.C&C Irradiator Service,LLC,Washington,DC,20006.)Abstract:Accurate dosimetry is a crucial component of small animal and preclinical irradiation studies.
基金financially supported by the Swiss National Science Foundation(grant number IZLRZ2_164058)the China Scholarship Council Ph.D.student exchange programthe Priority Academic Program Development of Jiangsu Higher Education Institution(PAPD)。
文摘Aerogels are ultra-lightweight,porous materials defined by a complex network of interconnected pores and nanostructures,which effectively suppress heat transfer,making them exceptional for thermal insulation.Furthermore,their porous architecture can trap and scatter light via multiple internal reflections,extending the optical path within the material.When combined with suitable light-absorbing materials,this feature significantly enhances light absorption(darkness).To validate this concept,mesoporous silica aerogel particles were incorporated into a resorcinol-formaldehyde(RF)sol,and the silica-to-RF ratio was optimized to achieve uniform carbon compound coatings on the silica pore walls.Notably,increasing silica loading raised the sol viscosity,enabling formulations ideal for direct ink writing processes with excellent shape fidelity for super-black topographical designs.The printed silica-RF green bodies exhibited remarkable mechanical strength and ultra-low thermal conductivity(15.8 m W m^(-1) K^(-1))prior to pyrolysis.Following pyrolysis,the composites maintained structural integrity and printed microcellular geometries while achieving super-black coloration(abs.99.56%in the 280-2500 nm range)and high photothermal conversion efficiency(94.2%).Additionally,these silica-carbon aerogel microcellulars demonstrated stable electrical conductivity and low electrochemical impedance.The synergistic combination of 3D printability and super-black photothermal features makes these composites highly versatile for multifunctional applications,including on-demand thermal management,and efficient solar-driven water production.
基金the National Key R&D Program of China(Project No.2022YFB4700100)National Natural Science Foundation of China(Grant Nos.61973298)+2 种基金Hong Kong Research Grants Council(GRF Project Number 11216120)the CAS-RGC Joint Laboratory Funding Scheme(Project Number JLFS/E-104/18)the Innovation Promotion Research Association of the Chinese Academy of Sciences(NO.2022199)。
文摘In the realm of secure information storage,optical encryption has emerged as a vital technique,particularly with the miniaturization of encryption devices.However,many existing systems lack the necessary reconfigurability and dynamic functionality.This study presents a novel approach through the development of dynamic optical-to-chemical energy conversion metamaterials,which enable enhanced steganography and multilevel information storage.We introduce a micro-dynamic multiple encryption device that leverages programmable optical properties in coumarin-based metamaterials,achieved through a direct laser writing grayscale gradient strategy.This methodology allows for the dynamic regulation of photoluminescent characteristics and cross-linking networks,facilitating innovative steganographic techniques under varying light conditions.The integration of a multi-optical field control system enables real-time adjustments to the material’s properties,enhancing the device’s reconfigurability and storage capabilities.Our findings underscore the potential of these metamaterials in advancing the field of microscale optical encryption,paving the way for future applications in dynamic storage and information security.
基金the support from the National Natural Science Foundation of China(Nos.22208376,UA22A20429)the Qingdao New Energy Shandong Laboratory Open Project(QNESL OP 202303)+3 种基金Shandong Provincial Natural Science Foundation(Nos.ZR2024QB175,ZR2023LFG005)Fundamental Research Funds for the Central Universities(No.25CX07002A)National Natural Science Foundation of China(Z202401390008)The Hunan Provincial Natural Science Foundation(2025JJ60301)。
文摘3D printing,as a versatile additive manufacturing technique,offers high design flexibility,rapid prototyping,minimal material waste,and the capability to fabricate complex,customized geometries.These attributes make it particularly well-suited for low-temperature hydrogen electrochemical conversion devices—specifically,proton exchange membrane fuel cells,proton exchange membrane electrolyzer cells,anion exchange membrane electrolyzer cells,and alkaline electrolyzers—which demand finely structured components such as catalyst layers,gas diffusion layers,electrodes,porous transport layers,and bipolar plates.This review provides a focused and critical summary of the current progress in applying 3D printing technologies to these key components.It begins with a concise introduction to the principles and classifications of mainstream 3D printing methods relevant to the hydrogen energy sector and proceeds to analyze their specific applications and performance impacts across different device architectures.Finally,the review identifies existing technical challenges and outlines future research directions to accelerate the integration of 3D printing in nextgeneration low-temperature hydrogen energy systems.
基金National Natural Science Foundation of China(No.U2241205)the Natural Science Basic Research Program of Shaanxi(Nos.2022JC-33,2023-GHZD-35,and 2024JC-ZDXM-25)+1 种基金the Fundamental Research Funds for the Central Universitiesthe National 111 Project to provide fund for conducting experiments。
文摘In this study,the design,analysis,manufacturing,and testing of a 3D-printed conformal microstrip array antenna for high-temperature environments is presented.3D printing technology is used to fabricate a curved ceramic substrate,and laser sintering and microdroplet spraying processes are used to add the conductive metal on the curved substrate.The problems of gain loss,bandwidth reduction,and frequency shift caused by high temperatures are addressed by using a proper antenna design,with parasitic patches,slots,and metal resonant cavities.The antenna prototype is characterized by the curved substrates and the conductive metals for the power dividers,the patch,and the ground plane;its performance is examined up to a temperature of 600℃in a muffle furnace and compared with the results from the numerical analysis.The results show that the antenna can effectively function at 600℃and even higher temperatures.
