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
Herein,a multifunctional photochromic two-dimensional metal-organic framework(PMOF),[Zn(bcbpy)0.5(pma)0.5(H_(2)O)]·3H_(2)O(1),was synthesized(H_(2)bcbpy·2Cl=1,1’-bis(3-carboxylatobenzyl)-(4,4’-bipyridinium...Herein,a multifunctional photochromic two-dimensional metal-organic framework(PMOF),[Zn(bcbpy)0.5(pma)0.5(H_(2)O)]·3H_(2)O(1),was synthesized(H_(2)bcbpy·2Cl=1,1’-bis(3-carboxylatobenzyl)-(4,4’-bipyridinium)dichloride,H_(4)pma=pyromellitic acid).It showed an efficient ultraviolet light detection ability with an obvious color change from colorless to blue and fast response to an ultraviolet intensity of as low as 0.001 mW cm^(-2)in the narrow-band UV region.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
Additive and solvent-free direct printing is critical for many applications,including smart electronics,solar cells,healthcare,and electrochemical energy storage.Although a few green techniques for direct patterning o...Additive and solvent-free direct printing is critical for many applications,including smart electronics,solar cells,healthcare,and electrochemical energy storage.Although a few green techniques for direct patterning of inorganic functional materials have been developed,they operate at small scale and require long processing times,restricting their effective translation from laboratory to market.Here we report a fast,liquid-free,cost-effective,and environmentally friendly aerosol-based printing method for fabricating linear or planar structures at microscale dimensions.In situ and on-demand generation of dry aerosol via pulsed laser ablation,coupled with real-time aerodynamical focusing using a co-flowing sheath gas,allows the deposition of a wide variety of materials on various substrates at room temperature and atmospheric pressure.Using silver as a test material,we systematically characterized the laser-generated aerosol deposits in terms of microstructural morphology,sintering activity,mass yield,density,and electrical performance,to show the relationship between process variability and underlying mechanisms.The capacity of high-throughput printing of silver deposits,with thickness up to 160μm,in a single pass was demonstrated.This rapid,efficient,and inkless printing process opens new and exciting opportunities for future applications that require easy-to-integrate components in printed electronic devices.展开更多
Quantum dot(QD)-based fluorescent inks offer high potential due to their tunable emission and high quantum yield,but their practical application suffers from poor environmental stability,aggregation,and challenges in ...Quantum dot(QD)-based fluorescent inks offer high potential due to their tunable emission and high quantum yield,but their practical application suffers from poor environmental stability,aggregation,and challenges in scalable flexible fabrication.In this study,a high-stability fluorescent ink was developed by incorporating QDs into a polydimethylsiloxane(PDMS)colloidal matrix.High-performance patterned films were then obtained via systematic optimization of screen-printing parameters,with film quality governed by substrate type(131μm PDMS),QD concentration(1.5 mg/mL),and screen mesh count(420 mesh).The optimized films exhibit outstanding environmental and photostability,retaining 75.6% of their fluorescence intensity after immersion in deionized water and 63.8% in 75%ethanol at 25℃ for 100 minutes.Under UV irradiation(365 nm,9 W,100 min),fluorescence intensity decreases by less than 20%.Utilizing their daylight transparency and UV-excitable luminescence,various patterns including QR codes and Code 93 standard barcodes were fabricated via screen printing with high pattern fidelity and machine readability.This study presents a scalable and reliable strategy for the fabrication of flexible,high-stability fluorescent films,supporting their integration into next-generation optoelectronic devices,advanced displays,and secure anti-counterfeiting.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
Because of the developed surface of the Triply PeriodicMinimumSurface(TPMS)structures,polylactide(PLA)products with a TPMS structure are thought to be promising bio soluble implants with the potential for targeted dru...Because of the developed surface of the Triply PeriodicMinimumSurface(TPMS)structures,polylactide(PLA)products with a TPMS structure are thought to be promising bio soluble implants with the potential for targeted drug delivery.For implants,mechanical properties are key performance characteristics,so understanding the deformation and failure mechanisms is essential for selecting the appropriate implant structure.The deformation and fracture processes in PLA samples with different interior architectures have been studied through computer simulation and experimental research.Two TPMS topologies,the Schwarz Diamond and Gyroid architectures,were used for the sample construction by 3D printing.ANSYS software was utilized to simulate compressive deformation.It was found that under the same load,the vonMises stresses in the Gyroid structure are higher than those in the Schwartz Diamond structure,which was associated with the different orientations of the cells in the studied structures in relation to the direction of the loading axis.The deformation process occurs in the local regions of the studied TPMS structures.Maximum von Mises stresses were observed in the vertical parts of the structures oriented along the load direction.It was found that,unlike the Gyroid,the Schwartz Diamond structure contains a frame that forms unique stiffening ribs,which ensures the redistribution of the load under the vertical loading direction.An analysis of the mechanical characteristics of PLA samples with the Schwartz Diamond and Gyroid structures produced by the Fused Deposition Modeling(FDM)method was correlated with computer simulation.The Schwarz Diamond-type structure was shown to have a higher absorption energy than the Gyroid one.A study of the fracture in PLA samples with various cell sizes revealed a particular feature related to the samples’periodic surface topology and the 3D printing process.Scanning electron microscopic(SEM)studies of the samples deformed by compression showed thatwith an increase in the density of the samples,the failure mechanism changes from ductile to quasi-brittle due to the complex participation of both cell deformation and fiber deformation.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]
基金support from the NSF of China(21571032,21271038)the analysis and testing foundation of Northeast Normal University.
文摘Herein,a multifunctional photochromic two-dimensional metal-organic framework(PMOF),[Zn(bcbpy)0.5(pma)0.5(H_(2)O)]·3H_(2)O(1),was synthesized(H_(2)bcbpy·2Cl=1,1’-bis(3-carboxylatobenzyl)-(4,4’-bipyridinium)dichloride,H_(4)pma=pyromellitic acid).It showed an efficient ultraviolet light detection ability with an obvious color change from colorless to blue and fast response to an ultraviolet intensity of as low as 0.001 mW cm^(-2)in the narrow-band UV region.
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financial support from the China Scholarship Council(No.202108220036)Advanced Microscopy Laboratory in Trinity College Dublin。
文摘Additive and solvent-free direct printing is critical for many applications,including smart electronics,solar cells,healthcare,and electrochemical energy storage.Although a few green techniques for direct patterning of inorganic functional materials have been developed,they operate at small scale and require long processing times,restricting their effective translation from laboratory to market.Here we report a fast,liquid-free,cost-effective,and environmentally friendly aerosol-based printing method for fabricating linear or planar structures at microscale dimensions.In situ and on-demand generation of dry aerosol via pulsed laser ablation,coupled with real-time aerodynamical focusing using a co-flowing sheath gas,allows the deposition of a wide variety of materials on various substrates at room temperature and atmospheric pressure.Using silver as a test material,we systematically characterized the laser-generated aerosol deposits in terms of microstructural morphology,sintering activity,mass yield,density,and electrical performance,to show the relationship between process variability and underlying mechanisms.The capacity of high-throughput printing of silver deposits,with thickness up to 160μm,in a single pass was demonstrated.This rapid,efficient,and inkless printing process opens new and exciting opportunities for future applications that require easy-to-integrate components in printed electronic devices.
文摘Quantum dot(QD)-based fluorescent inks offer high potential due to their tunable emission and high quantum yield,but their practical application suffers from poor environmental stability,aggregation,and challenges in scalable flexible fabrication.In this study,a high-stability fluorescent ink was developed by incorporating QDs into a polydimethylsiloxane(PDMS)colloidal matrix.High-performance patterned films were then obtained via systematic optimization of screen-printing parameters,with film quality governed by substrate type(131μm PDMS),QD concentration(1.5 mg/mL),and screen mesh count(420 mesh).The optimized films exhibit outstanding environmental and photostability,retaining 75.6% of their fluorescence intensity after immersion in deionized water and 63.8% in 75%ethanol at 25℃ for 100 minutes.Under UV irradiation(365 nm,9 W,100 min),fluorescence intensity decreases by less than 20%.Utilizing their daylight transparency and UV-excitable luminescence,various patterns including QR codes and Code 93 standard barcodes were fabricated via screen printing with high pattern fidelity and machine readability.This study presents a scalable and reliable strategy for the fabrication of flexible,high-stability fluorescent films,supporting their integration into next-generation optoelectronic devices,advanced displays,and secure anti-counterfeiting.
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.
文摘Because of the developed surface of the Triply PeriodicMinimumSurface(TPMS)structures,polylactide(PLA)products with a TPMS structure are thought to be promising bio soluble implants with the potential for targeted drug delivery.For implants,mechanical properties are key performance characteristics,so understanding the deformation and failure mechanisms is essential for selecting the appropriate implant structure.The deformation and fracture processes in PLA samples with different interior architectures have been studied through computer simulation and experimental research.Two TPMS topologies,the Schwarz Diamond and Gyroid architectures,were used for the sample construction by 3D printing.ANSYS software was utilized to simulate compressive deformation.It was found that under the same load,the vonMises stresses in the Gyroid structure are higher than those in the Schwartz Diamond structure,which was associated with the different orientations of the cells in the studied structures in relation to the direction of the loading axis.The deformation process occurs in the local regions of the studied TPMS structures.Maximum von Mises stresses were observed in the vertical parts of the structures oriented along the load direction.It was found that,unlike the Gyroid,the Schwartz Diamond structure contains a frame that forms unique stiffening ribs,which ensures the redistribution of the load under the vertical loading direction.An analysis of the mechanical characteristics of PLA samples with the Schwartz Diamond and Gyroid structures produced by the Fused Deposition Modeling(FDM)method was correlated with computer simulation.The Schwarz Diamond-type structure was shown to have a higher absorption energy than the Gyroid one.A study of the fracture in PLA samples with various cell sizes revealed a particular feature related to the samples’periodic surface topology and the 3D printing process.Scanning electron microscopic(SEM)studies of the samples deformed by compression showed thatwith an increase in the density of the samples,the failure mechanism changes from ductile to quasi-brittle due to the complex participation of both cell deformation and fiber deformation.