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Toward understanding the microstructure characteristics,phase selection and magnetic properties of laser additive manufactured Nd-Fe-B permanent magnets 被引量:1
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作者 Bo Yao Nan Kang +6 位作者 Xiangyu Li Dou Li Mohamed EL Mansori Jing Chen Haiou Yang Hua Tan Xin Lin 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第1期277-294,共18页
Nd-Fe-B permanent magnets play a crucial role in energy conversion and electronic devices.The essential magnetic properties of Nd-Fe-B magnets,particularly coercivity and remanent magnetization,are significantly infue... Nd-Fe-B permanent magnets play a crucial role in energy conversion and electronic devices.The essential magnetic properties of Nd-Fe-B magnets,particularly coercivity and remanent magnetization,are significantly infuenced by the phase characteristics and microstructure.In this work,Nd-Fe-B magnets were manufactured using vacuum induction melting(VIM),laser directed energy deposition(LDED)and laser powder bed fusion(LPBF)technologies.Themicrostructure evolution and phase selection of Nd-Fe-B magnets were then clarified in detail.The results indicated that the solidification velocity(V)and cooling rate(R)are key factors in the phase selection.In terms of the VIM-casting Nd-Fe-B magnet,a large volume fraction of theα-Fe soft magnetic phase(39.7 vol.%)and Nd2Fe17Bxmetastable phase(34.7 vol.%)areformed due to the low R(2.3×10-1?C s-1),whereas only a minor fraction of the Nd2Fe14B hard magnetic phase(5.15 vol.%)is presented.For the LDED-processed Nd-Fe-B deposit,although the Nd2Fe14B hard magnetic phase also had a low value(3.4 vol.%)as the values of V(<10-2m s-1)and R(5.06×103?C s-1)increased,part of theα-Fe soft magnetic phase(31.7vol.%)is suppressed,and a higher volume of Nd2Fe17Bxmetastable phases(47.5 vol.%)areformed.As a result,both the VIM-casting and LDED-processed Nd-Fe-B deposits exhibited poor magnetic properties.In contrast,employing the high values of V(>10-2m s-1)and R(1.45×106?C s-1)in the LPBF process resulted in the substantial formation of the Nd2Fe14B hard magnetic phase(55.8 vol.%)directly from the liquid,while theα-Fe soft magnetic phase and Nd2Fe17Bxmetastable phase precipitation are suppressed in the LPBF-processed Nd-Fe-B magnet.Additionally,crystallographic texture analysis reveals that the LPBF-processedNd-Fe-B magnets exhibit isotropic magnetic characteristics.Consequently,the LPBF-processed Nd-Fe-B deposit,exhibiting a coercivity of 656 k A m-1,remanence of 0.79 T and maximum energy product of 71.5 k J m-3,achieved an acceptable magnetic performance,comparable to other additive manufacturing processed Nd-Fe-B magnets from MQP(Nd-lean)Nd-Fe-Bpowder. 展开更多
关键词 laser additive manufacturing(LAM) Nd-Fe-B permanent magnets numerical simulation microstructure magnetic properties
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Additively manufactured Ti–Ta–Cu alloys for the next-generation load-bearing implants 被引量:1
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作者 Amit Bandyopadhyay Indranath Mitra +4 位作者 Sushant Ciliveri Jose D Avila William Dernell Stuart B Goodman Susmita Bose 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第1期353-374,共22页
Bacterial colonization of orthopedic implants is one of the leading causes of failure and clinical complexities for load-bearing metallic implants. Topical or systemic administration of antibiotics may not offer the m... Bacterial colonization of orthopedic implants is one of the leading causes of failure and clinical complexities for load-bearing metallic implants. Topical or systemic administration of antibiotics may not offer the most efficient defense against colonization, especially in the case of secondary infection, leading to surgical removal of implants and in some cases even limbs. In this study, laser powder bed fusion was implemented to fabricate Ti3Al2V alloy by a 1:1 weight mixture of CpTi and Ti6Al4V powders. Ti-Tantalum(Ta)–Copper(Cu) alloys were further analyzed by the addition of Ta and Cu into the Ti3Al2V custom alloy. The biological,mechanical, and tribo-biocorrosion properties of Ti3Al2V alloy were evaluated. A 10 wt.% Ta(10Ta) and 3 wt.% Cu(3Cu) were added to the Ti3Al2V alloy to enhance biocompatibility and impart inherent bacterial resistance. Additively manufactured implants were investigated for resistance against Pseudomonas aeruginosa and Staphylococcus aureus strains of bacteria for up to 48 h. A 3 wt.% Cu addition to Ti3Al2V displayed improved antibacterial efficacy, i.e.78%–86% with respect to CpTi. Mechanical properties for Ti3Al2V–10Ta–3Cu alloy were evaluated, demonstrating excellent fatigue resistance, exceptional shear strength, and improved tribological and tribo-biocorrosion characteristics when compared to Ti6Al4V. In vivo studies using a rat distal femur model revealed improved early-stage osseointegration for alloys with10 wt.% Ta addition compared to CpTi and Ti6Al4V. The 3 wt.% Cu-added compositions displayed biocompatibility and no adverse infammatory response in vivo. Our results establish the Ti3Al2V–10Ta–3Cu alloy’s synergistic effect on improving both in vivo biocompatibility and microbial resistance for the next generation of load-bearing metallic implants. 展开更多
关键词 TI6AL4V load-bearing implants additive manufacturing 3D printing antibacterial performance
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Post processing of additive manufactured Mg alloys:Current status,challenges,and opportunities
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作者 Nooruddin Ansari Fatima Ghassan Alabtah +1 位作者 Mohammad I.Albakri Marwan Khraisheh 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第4期1283-1310,共28页
Magnesium(Mg)and its alloys are emerging as a structural material for the aerospace,automobile,and electronics industries,driven by the imperative of weight reduction.They are also drawing notable attention in the med... Magnesium(Mg)and its alloys are emerging as a structural material for the aerospace,automobile,and electronics industries,driven by the imperative of weight reduction.They are also drawing notable attention in the medical industries owing to their biodegradability and a lower elastic modulus comparable to bone.The ability to manufacture near-net shape products featuring intricate geometries has sparked huge interest in additive manufacturing(AM)of Mg alloys,reflecting a transformation in the manufacturing sectors.However,AM of Mg alloys presents more formidable challenges due to inherent properties,particularly susceptibility to oxidation,gas trapping,high thermal expansion coefficient,and low solidification temperature.This leads to defects such as porosity,lack of fusion,cracking,delamination,residual stresses,and inhomogeneity,ultimately influencing the mechanical,corrosion,and surface properties of AM Mg alloys.To address these issues,post-processing of AM Mg alloys are often needed to make them suitable for application.The present article reviews all post-processing techniques adapted for AM Mg alloys to date,including heat treatment,hot isostatic pressing,friction stir processing,and surface peening.The utilization of these methods within the hybrid AM process,employing interlayer post-processing,is also discussed.Optimal post-processing conditions are reported,and their influence on the microstructure,mechanical,and corrosion properties are detailed.Additionally,future prospects and research directions are proposed. 展开更多
关键词 Magnesium alloy Additive manufacturing POST-PROCESSING Heat treatment HIP
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Quasi-static and dynamic compressive behaviour of additively manufactured Menger fractal cube structures
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作者 Damith Mohotti Dakshitha Weerasinghe +3 位作者 Madhusha Bogahawaththa Hongxu Wang Kasun Wijesooriya Paul JHazell 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第7期39-49,共11页
This paper presents the first-ever investigation of Menger fractal cubes'quasi-static compression and impact behaviour.Menger cubes with different void ratios were 3D printed using polylactic acid(PLA)with dimensi... This paper presents the first-ever investigation of Menger fractal cubes'quasi-static compression and impact behaviour.Menger cubes with different void ratios were 3D printed using polylactic acid(PLA)with dimensions of 40 mm×40 mm×40 mm.Three different orders of Menger cubes with different void ratios were considered,namely M1 with a void ratio of 0.26,M2 with a void ratio of 0.45,and M3with a void ratio of 0.60.Quasi-static Compression tests were conducted using a universal testing machine,while the drop hammer was used to observe the behaviour under impact loading.The fracture mechanism,energy efficiency and force-time histories were studied.With the structured nature of the void formation and predictability of the failure modes,the Menger geometry showed some promise compared to other alternatives,such as foams and honeycombs.With the increasing void ratio,the Menger geometries show force-displacement behaviour similar to hyper-elastic materials such as rubber and polymers.The third-order Menger cubes showed the highest energy absorption efficiency compared to the other two geometries in this study.The findings of the present work reveal the possibility of using additively manufactured Menger geometries as an energy-efficient system capable of reducing the transmitting force in applications such as crash barriers. 展开更多
关键词 Additive manufacturing Fractal geometries Menger cube Energy absorption QUASI-STATIC
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Additive manufactured osseointegrated screws with hierarchical design
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作者 Wenbo Yang Hao Chen +6 位作者 Haotian Bai Yifu Sun Aobo Zhang Yang Liu Yuchao Song Qing Han Jincheng Wang 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第2期206-235,共30页
Bone screws are devices used to fix implants or bones to bones.However,conventional screws are mechanically fixed with thread and often face long-term failure due to poor osseointegration.To improve osseointegration,s... Bone screws are devices used to fix implants or bones to bones.However,conventional screws are mechanically fixed with thread and often face long-term failure due to poor osseointegration.To improve osseointegration,screws are evolving from solid and smooth to porous and rough.Additive manufacturing(AM)offers a high degree of manufacturing freedom,enabling the preparation of predesigned screws that are porous and rough.This paper provides an overview of the problems currently faced by bone screws:long-term loosening and screw breakage.Next,advances in osseointegrated screws are summarized hierarchically(sub-micro,micro,and macro).At the sub-microscale level,we describe surface-modification techniques for enhancing osseointegration.At the micro level,we summarize the micro-design parameters that affect the mechanical and biological properties of porous osseointegrated screws,including porosity,pore size,and pore shape.In addition,we highlight three promising pore shapes:triply periodic minimal surface,auxetic structure with negative Poisson ratio,and the Voronoi structure.At the macro level,we outline the strategies of graded design,gradient design,and topology optimization design to improve the mechanical strength of porous osseointegrated screws.Simultaneously,this paper outlines advances in AM technology for enhancing the mechanical properties of porous osseointegrated screws.AM osseointegrated screws with hierarchical design are expected to provide excellent long-term fixation and the required mechanical strength. 展开更多
关键词 Bone screws Additive manufacturing Architecture design Surface modification
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Method for Detecting Industrial Defects in Intelligent Manufacturing Using Deep Learning
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作者 Bowen Yu Chunli Xie 《Computers, Materials & Continua》 SCIE EI 2024年第1期1329-1343,共15页
With the advent of Industry 4.0,marked by a surge in intelligent manufacturing,advanced sensors embedded in smart factories now enable extensive data collection on equipment operation.The analysis of such data is pivo... With the advent of Industry 4.0,marked by a surge in intelligent manufacturing,advanced sensors embedded in smart factories now enable extensive data collection on equipment operation.The analysis of such data is pivotal for ensuring production safety,a critical factor in monitoring the health status of manufacturing apparatus.Conventional defect detection techniques,typically limited to specific scenarios,often require manual feature extraction,leading to inefficiencies and limited versatility in the overall process.Our research presents an intelligent defect detection methodology that leverages deep learning techniques to automate feature extraction and defect localization processes.Our proposed approach encompasses a suite of components:the high-level feature learning block(HLFLB),the multi-scale feature learning block(MSFLB),and a dynamic adaptive fusion block(DAFB),working in tandem to extract meticulously and synergistically aggregate defect-related characteristics across various scales and hierarchical levels.We have conducted validation of the proposed method using datasets derived from gearbox and bearing assessments.The empirical outcomes underscore the superior defect detection capability of our approach.It demonstrates consistently high performance across diverse datasets and possesses the accuracy required to categorize defects,taking into account their specific locations and the extent of damage,proving the method’s effectiveness and reliability in identifying defects in industrial components. 展开更多
关键词 Industrial defect detection deep learning intelligent manufacturing
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Characterization and Modeling of Mechanical Properties of Additively Manufactured Coconut Fiber-Reinforced Polypropylene Composites
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作者 George Mosi Bernard W. Ikua +1 位作者 Samuel K. Kabini James W. Mwangi 《Advances in Materials Physics and Chemistry》 CAS 2024年第6期95-112,共18页
In the face of the increased global campaign to minimize the emission of greenhouse gases and the need for sustainability in manufacturing, there is a great deal of research focusing on environmentally benign and rene... In the face of the increased global campaign to minimize the emission of greenhouse gases and the need for sustainability in manufacturing, there is a great deal of research focusing on environmentally benign and renewable materials as a substitute for synthetic and petroleum-based products. Natural fiber-reinforced polymeric composites have recently been proposed as a viable alternative to synthetic materials. The current work investigates the suitability of coconut fiber-reinforced polypropylene as a structural material. The coconut fiber-reinforced polypropylene composites were developed. Samples of coconut fiber/polypropylene (PP) composites were prepared using Fused Filament Fabrication (FFF). Tests were then conducted on the mechanical properties of the composites for different proportions of coconut fibers. The results obtained indicate that the composites loaded with 2 wt% exhibited the highest tensile and flexural strength, while the ones loaded with 3 wt% had the highest compression strength. The ultimate tensile and flexural strength at 2 wt% were determined to be 34.13 MPa and 70.47 MPa respectively. The compression strength at 3 wt% was found to be 37.88 MPa. Compared to pure polypropylene, the addition of coconut fibers increased the tensile, flexural, and compression strength of the composite. In the study, an artificial neural network model was proposed to predict the mechanical properties of polymeric composites based on the proportion of fibers. The model was found to predict data with high accuracy. 展开更多
关键词 Additive manufacturing Artificial Neural Network Mechanical Properties Natural Fibers POLYPROPYLENE
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Effect of thermo-mechanical treatment on microstructure and mechanical properties of wire-arc additively manufactured Al-Cu alloy
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作者 ZHANG Tao QIN Zhen-yang +2 位作者 GONG Hai WU Yun-xin CHEN Xin 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2181-2193,共13页
Wire-arc additive manufacture(WAAM)has great potential for manufacturing of Al-Cu components.However,inferior mechanical properties of WAAM deposited material restrict its industrial application.Inter-layer cold rolli... Wire-arc additive manufacture(WAAM)has great potential for manufacturing of Al-Cu components.However,inferior mechanical properties of WAAM deposited material restrict its industrial application.Inter-layer cold rolling and thermo-mechanical heat treatment(T8)with pre-stretching deformation between solution and aging treatment were adopted in this study.Their effects on hardness,mechanical properties and microstructure were analyzed and compared to the conventional heat treatment(T6).The results show that cold rolling increases the hardness and strengths,which further increase with T8 treatment.The ultimate tensile strength(UTS)of 513 MPa and yield stress(YS)of 413 MPa can be obtained in the inter-layer cold-rolled sample with T8 treatment,which is much higher than that in the as-deposited samples.The cold-rolled samples show higher elongation than that of as-deposited ones due to significant elimination of porosity in cold rolling;while both the T6 and T8 treatments decrease the elongation.The cold rolling and pre-stretching deformation both contribute to the formation of dense and dispersive precipitatedθ′phases,which inhibits the dislocation movement and enhances the strengths;as a result,T8 treatment shows better strengthening effect than the T6 treatment.The strengthening mechanism was analyzed and it was mainly related to work hardening and precipitation strengthening. 展开更多
关键词 wire-arc additive manufacture inter-layer cold rolling thermal-mechanical treatment microstructure mechanical properties strengthening mechanism
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Mechanical behavior and response mechanism of porous metal structures manufactured by laser powder bed fusion under compressive loading
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作者 Xuanming Cai Yang Hou +6 位作者 Wei Zhang Zhiqiang Fan Yubo Gao Junyuan Wang Heyang Sun Zhujun Zhang Wenshu Yang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第4期737-749,共13页
Al Si10Mg porous protective structure often produces different damage forms under compressive loading,and these damage modes affect its protective function.In order to well meet the service requirements,there is an ur... Al Si10Mg porous protective structure often produces different damage forms under compressive loading,and these damage modes affect its protective function.In order to well meet the service requirements,there is an urgent need to comprehensively understand the mechanical behavior and response mechanism of AlSi10Mg porous structures under compressive loading.In this paper,Al Si10Mg porous structures with three kinds of volume fractions are designed and optimized to meet the requirements of high-impact,strong-energy absorption,and lightweight characteristics.The mechanical behaviors of AlSi10Mg porous structures,including the stress-strain relationship,structural bearing state,deformation and damage modes,and energy absorption characteristics,were obtained through experimental studies at different loading rates.The damage pattern of the damage section indicates that AlSi10Mg porous structures have both ductile and brittle mechanical properties.Numerical simulation studies show that the AlSi10Mg porous structure undergoes shear damage due to relative misalignment along the diagonal cross-section,and the damage location is almost at 45°to the load direction,which is the most direct cause of its structural damage,revealing the damage mechanism of AlSi10Mg porous structures under the compressive load.The normalized energy absorption model constructed in the paper well interprets the energy absorption state of Al Si10Mg porous structures and gives the sensitive location of the structures,and the results of this paper provide important references for peers in structural design and optimization. 展开更多
关键词 AlSi10Mg additive manufacture energy absorption characteristics damage by deformation mechanical behavior
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Advances of embedded resistive random access memory in industrial manufacturing and its potential applications
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作者 Zijian Wang Yixian Song +7 位作者 Guobin Zhang Qi Luo Kai Xu Dawei Gao Bin Yu Desmond Loke Shuai Zhong Yishu Zhang 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第3期175-214,共40页
Embedded memory,which heavily relies on the manufacturing process,has been widely adopted in various industrial applications.As the field of embedded memory continues to evolve,innovative strategies are emerging to en... Embedded memory,which heavily relies on the manufacturing process,has been widely adopted in various industrial applications.As the field of embedded memory continues to evolve,innovative strategies are emerging to enhance performance.Among them,resistive random access memory(RRAM)has gained significant attention due to its numerousadvantages over traditional memory devices,including high speed(<1 ns),high density(4 F^(2)·n^(-1)),high scalability(~nm),and low power consumption(~pJ).This review focuses on the recent progress of embedded RRAM in industrial manufacturing and its potentialapplications.It provides a brief introduction to the concepts and advantages of RRAM,discusses the key factors that impact its industrial manufacturing,and presents the commercial progress driven by cutting-edge nanotechnology,which has been pursued by manysemiconductor giants.Additionally,it highlights the adoption of embedded RRAM in emerging applications within the realm of the Internet of Things and future intelligent computing,with a particular emphasis on its role in neuromorphic computing.Finally,the review discusses thecurrent challenges and provides insights into the prospects of embedded RRAM in the era of big data and artificial intelligence. 展开更多
关键词 embedded resistive random access memory industrial manufacturing intelligent computing advanced process node
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基于Clinical Trials数据库的癌性疼痛治疗药物临床试验分析
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作者 储召群 马菁文 +3 位作者 尚天则 余早勤 何光照 王忱诚 《医药导报》 CAS 北大核心 2024年第10期1640-1645,共6页
目的了解近年来癌性疼痛(癌痛)治疗药物临床试验的趋势和特点,为癌痛治疗药物的开发和临床研究提供参考依据。方法从Clinical Trials数据库中检索1987—2022年癌痛治疗药物临床试验的相关信息,从试验类型、备案时间、申报地区、癌痛类... 目的了解近年来癌性疼痛(癌痛)治疗药物临床试验的趋势和特点,为癌痛治疗药物的开发和临床研究提供参考依据。方法从Clinical Trials数据库中检索1987—2022年癌痛治疗药物临床试验的相关信息,从试验类型、备案时间、申报地区、癌痛类型、癌痛治疗药物等角度进行描述性分析。结果筛选出临床试验376项,由研究者发起的试验(IIT)项目数多于注册类试验(IST),其中北美洲的总项目数、IIT和IST项目数最多;试验总项目数和IST项目数先增长后回落,IIT的试验项目数稳步增长。针对慢性癌痛、爆发性癌痛和重度癌痛的研究相对较多。研究对象以阿片类药物尤其是芬太尼的占比最高。结论癌痛治疗药物临床试验对推进癌痛治疗药物治疗发挥了重要作用,未来有待进一步加强IST在新型癌痛治疗药物的研究和开展更多IIT研究,以更好地优化癌痛治疗效果。 展开更多
关键词 药物临床试验 癌性疼痛 研究者发起的试验 注册类试验
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Enhanced strength-ductility synergy in a wire and arc additively manufactured Mg alloy via tuning interlayer dwell time 被引量:1
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作者 Dong Ma Chunjie Xu +6 位作者 Shang Sui Jun Tian Can Guo Xiangquan Wu Zhongming Zhang Dan Shechtman Sergei Remennik 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2023年第12期4696-4709,共14页
Strength-ductility trade-off is a common issue in Mg alloys. This work proposed that a synergistic enhancement of strength and ductility could be achieved through tuning interlayer dwell time(IDT) in the wire and arc ... Strength-ductility trade-off is a common issue in Mg alloys. This work proposed that a synergistic enhancement of strength and ductility could be achieved through tuning interlayer dwell time(IDT) in the wire and arc additive manufacturing(WAAM) process of Mg alloy.The thermal couples were used to monitor the thermal history during the WAAM process. Additionally, the effect of different IDTs on the microstructure characteristics and resultant mechanical properties of WAAM-processed Mg alloy thin-wall were investigated. The results showed that the stable temperature of the thin-wall component could reach 290 ℃ at IDT=0s, indicating that the thermal accumulation effect was remarkable. Consequently, unimodal coarse grains with an average size of 39.6 μm were generated, and the resultant room-temperature tensile property was poor. With the IDT extended to 60s, the thermal input and thermal dissipation reached a balance, and the stable temperature was only 170 ℃, closing to the initial temperature of the substrate. A refined grain structure with bimodal size distribution was obtained. The remelting zone had fine grains with the size of 15.2 μm, while the arc zone owned coarse grains with the size of 24.5 μm.The alternatively distributed coarse and fine grains lead to the elimination of strength-ductility trade-off. The ultimate tensile strength and elongation of the samples at IDT=60s are increased by 20.6 and 75.0% of those samples at IDT=0s, respectively. The findings will facilitate the development of additive manufacturing processes for advanced Mg alloys. 展开更多
关键词 Wire arc additive manufacturing Interlayer dwell time Strength-ductility Magnesium alloys
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A facile strategy for tuning the density of surface-grafted biomolecules for melt extrusion-based additive manufacturing applications 被引量:1
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作者 I.A.O.Beeren G.Dos Santos +8 位作者 P.J.Dijkstra C.Mota J.Bauer H.Ferreira Rui L.Reis N.Neves S.Camarero-Espinosa M.B.Baker L.Moroni 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第3期277-291,共15页
Melt extrusion-based additive manufacturing(ME-AM)is a promising technique to fabricate porous scaffolds for tissue engi-neering applications.However,most synthetic semicrystalline polymers do not possess the intrinsi... Melt extrusion-based additive manufacturing(ME-AM)is a promising technique to fabricate porous scaffolds for tissue engi-neering applications.However,most synthetic semicrystalline polymers do not possess the intrinsic biological activity required to control cell fate.Grafting of biomolecules on polymeric surfaces of AM scaffolds enhances the bioactivity of a construct;however,there are limited strategies available to control the surface density.Here,we report a strategy to tune the surface density of bioactive groups by blending a low molecular weight poly(ε-caprolactone)5k(PCL5k)containing orthogonally reactive azide groups with an unfunctionalized high molecular weight PCL75k at different ratios.Stable porous three-dimensional(3D)scaf-folds were then fabricated using a high weight percentage(75 wt.%)of the low molecular weight PCL 5k.As a proof-of-concept test,we prepared films of three different mass ratios of low and high molecular weight polymers with a thermopress and reacted with an alkynated fluorescent model compound on the surface,yielding a density of 201-561 pmol/cm^(2).Subsequently,a bone morphogenetic protein 2(BMP-2)-derived peptide was grafted onto the films comprising different blend compositions,and the effect of peptide surface density on the osteogenic differentiation of human mesenchymal stromal cells(hMSCs)was assessed.After two weeks of culturing in a basic medium,cells expressed higher levels of BMP receptor II(BMPRII)on films with the conjugated peptide.In addition,we found that alkaline phosphatase activity was only significantly enhanced on films contain-ing the highest peptide density(i.e.,561 pmol/cm^(2)),indicating the importance of the surface density.Taken together,these results emphasize that the density of surface peptides on cell differentiation must be considered at the cell-material interface.Moreover,we have presented a viable strategy for ME-AM community that desires to tune the bulk and surface functionality via blending of(modified)polymers.Furthermore,the use of alkyne-azide“click”chemistry enables spatial control over bioconjugation of many tissue-specific moieties,making this approach a versatile strategy for tissue engineering applications. 展开更多
关键词 Additive manufacturing BLENDING Surface functionalization Surface density Click chemistry HUMAN
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Repositioning fertilizer manufacturing subsidies for improving food security and reducing greenhouse gas emissions in China 被引量:1
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作者 Zongyi Wu Xiaolong Feng +1 位作者 Yumei Zhang Shenggen Fan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期430-443,共14页
China removed fertilizer manufacturing subsidies from 2015 to 2018 to bolster market-oriented reforms and foster environmentally sustainable practices.However,the impact of this policy reform on food security and the ... China removed fertilizer manufacturing subsidies from 2015 to 2018 to bolster market-oriented reforms and foster environmentally sustainable practices.However,the impact of this policy reform on food security and the environment remains inadequately evaluated.Moreover,although green and low-carbon technologies offer environmental advantages,their widespread adoption is hindered by prohibitively high costs.This study analyzes the impact of removing fertilizer manufacturing subsidies and explores the potential feasibility of redirecting fertilizer manufacturing subsidies to invest in the diffusion of these technologies.Utilizing the China Agricultural University Agri-food Systems model,we analyzed the potential for achieving mutually beneficial outcomes regarding food security and environmental sustainability.The findings indicate that removing fertilizer manufacturing subsidies has reduced greenhouse gas(GHG)emissions from agricultural activities by 3.88 million metric tons,with minimal impact on food production.Redirecting fertilizer manufacturing subsidies to invest in green and low-carbon technologies,including slow and controlled-release fertilizer,organic-inorganic compound fertilizers,and machine deep placement of fertilizer,emerges as a strategy to concurrently curtail GHG emissions,ensure food security,and secure robust economic returns.Finally,we propose a comprehensive set of government interventions,including subsidies,field guidance,and improved extension systems,to promote the widespread adoption of these technologies. 展开更多
关键词 food security fertilizer manufacturing subsidies agri-food systems greenhouse gas emissions
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Pumpability of Manufactured Sand Self-compacting Concrete
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作者 LI Huajian HUANG Fali +5 位作者 TU Haifeng SUN Deyi WANG Zhen YI Zhonglai YANG Zhiqiang XIE Yongjiang 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第6期1382-1390,共9页
By the addition of superplasticizer and air entraining agent,manufactured sand selfcompacting concrete(MS SCC)with slump flow varying from 500 to 700 mm and air content varying from 2.0%to 9.0%were prepared and the pu... By the addition of superplasticizer and air entraining agent,manufactured sand selfcompacting concrete(MS SCC)with slump flow varying from 500 to 700 mm and air content varying from 2.0%to 9.0%were prepared and the pumpability of MS SCC was studied by a sliding pipe rheometer(Sliper).According to the Kaplan’s model,the initial pump pressure and the pump resistance of MS SCC were obtained.Meanwhile,rheological properties including the yield stress and the plastic viscosity of MS SCC were measured by a rheometer.The experimental results show that the increase of slump flow contributes to a higher pumpability and a proper air content,i e,6%is beneficial for the pumpability of MS SCC.Due to the existence of stone powder and stronger angularity of MS,the initial pump pressure of MS SCC is only about 60%-88%that of river sand(RS)SCC with the same slump flow and air content,indicating that MS SCC possesses a higher pumpability than RS SCC. 展开更多
关键词 manufactured sand self-compacting concrete PUMPABILITY sliding pipe rheometer RHEOLOGY
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Molecular insights into clinical trials for immune checkpoint inhibitors in colorectal cancer:Unravelling challenges and future directions 被引量:1
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作者 Samantha Sharma Naresh Singh +5 位作者 Anita Ahmed Turk Isabella Wan Akshay Guttikonda Julia Lily Dong Xinna Zhang Mateusz Opyrchal 《World Journal of Gastroenterology》 SCIE CAS 2024年第13期1815-1835,共21页
Colorectal cancer(CRC)is a complex disease with diverse etiologies and clinical outcomes.Despite considerable progress in development of CRC therapeutics,challenges remain regarding the diagnosis and management of adv... Colorectal cancer(CRC)is a complex disease with diverse etiologies and clinical outcomes.Despite considerable progress in development of CRC therapeutics,challenges remain regarding the diagnosis and management of advanced stage metastatic CRC(mCRC).In particular,the five-year survival rate is very low since mCRC is currently rarely curable.Over the past decade,cancer treatment has significantly improved with the introduction of cancer immunotherapies,specifically immune checkpoint inhibitors.Therapies aimed at blocking immune checkpoints such as PD-1,PD-L1,and CTLA-4 target inhibitory pathways of the immune system,and thereby enhance anti-tumor immunity.These therapies thus have shown promising results in many clinical trials alone or in combination.The efficacy and safety of immunotherapy,either alone or in combination with CRC,have been investigated in several clinical trials.Clinical trials,including KEYNOTE-164 and CheckMate 142,have led to Food and Drug Administration approval of the PD-1 inhibitors pembrolizumab and nivolumab,respectively,for the treatment of patients with unresectable or metastatic microsatellite instability-high or deficient mismatch repair CRC.Unfortunately,these drugs benefit only a small percentage of patients,with the benefits of immunotherapy remaining elusive for the vast majority of CRC patients.To this end,primary and secondary resistance to immunotherapy remains a significant issue,and further research is necessary to optimize the use of immunotherapy in CRC and identify biomarkers to predict the response.This review provides a comprehensive overview of the clinical trials involving immune checkpoint inhibitors in CRC.The underlying rationale,challenges faced,and potential future steps to improve the prognosis and enhance the likelihood of successful trials in this field are discussed. 展开更多
关键词 Colorectal cancer Immune checkpoint inhibitors Clinical trials Immunotherapy Microsatellite instability Microsatellite stability DNA mismatch repair
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Strengthening and toughening of additively manufactured Ti-6Al-4V alloy by hybrid deposition and synchronous micro-rolling
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作者 Kui Cheng Hao Song +6 位作者 Xin-wang Liu Ming-bo Zhang Fei-hu Shan Kun He Zi-tian Fan Gui-lan Wang Hai-ou Zhang 《China Foundry》 SCIE CAS CSCD 2023年第3期189-196,共8页
To overcome the disadvantages of inhomogeneous microstructures and poor mechanical properties of additively manufactured Ti-6Al-4V alloys,a novel technique of hybrid deposition and synchronous micro-rolling is propose... To overcome the disadvantages of inhomogeneous microstructures and poor mechanical properties of additively manufactured Ti-6Al-4V alloys,a novel technique of hybrid deposition and synchronous micro-rolling is proposed.The micro-rolling leads to equiaxed prior β grains,thin discontinuous intergranular α,and equiaxed primary α,in contrast to the coarse columnar prior β grains without the application of micro-rolling.The recrystallization by micro-rolling results in discontinuous intergranular α via the mechanism of strain and interface-induced grain boundary migration.The evolution of α globularization,driven by a solute concentration gradient,starts from the sub-boundary until the formation of equiaxed primary α.Simultaneous strengthening and toughening are achieved,which means an increase in yield strength,ultimate tensile strength,fracture elongation,and work hardening rate.The formation of α recrystallization leads to more fine grain boundaries to strengthen the yield strength,and the improvement of ductility is due to the better-coordinated deformation ability of discontinuous intergranular α and equiaxed primary α.As a result,the fracture mode in micro-rolling changes from intergranular type to transgranular type. 展开更多
关键词 TI-6AL-4V additive manufacturing micro-rolling grain refinement tensile property
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Research on the Industrial Transfer and Restructuring Path of the Energy-Intensive Manufacturing Industry in Western China
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作者 Wang Fang Chen Shiwei Qu Tiantian 《Contemporary Social Sciences》 2023年第2期21-37,共17页
The orderly transfer of the manufacturing industry is a major action in China’s industrial restructuring.From the perspective of industrial transfer,we used the concentration ratio to depict the trend of the industri... The orderly transfer of the manufacturing industry is a major action in China’s industrial restructuring.From the perspective of industrial transfer,we used the concentration ratio to depict the trend of the industrial transfer of energy-intensive manufacturing in the eastern,central,and western regions since the policy of large-scale development of western China was implemented.We measured the total factor productivity(TFP)of western China using the DEAMalmquist index method.We conducted a regression analysis to measure the effect of western China’s undertaking of the transfer of the energy-intensive manufacturing industry.The findings of this study show that during 2000–2019,eleven provinces(as well as autonomous regions and municipalities)in western China undertook the transfer of the energy-intensive manufacturing industry from the eastern and central regions to varying degrees,exhibiting significant phase features regarding the rate and scale of transfers.Further investigation also demonstrated that the transfer of energy-intensive manufacturing industries has a U-shaped enabling effect on TFP in western China with the scale effect greater than the technology effect.Therefore,it is necessary to transition from“extensive industrial transfer”at the cost of the labor force,land,and resources to“modern industrial transfer”featured by technology and efficiency improvements to contribute to industrial restructuring in western China effectively. 展开更多
关键词 industrial transfer energy-intensive manufacturing industry western China total factor productivity(TFP) U-shaped relationship
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The Effects of Industrial Park Development on Manufacturing Firms’Performance in Ethiopia
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作者 Desta Tesfaw 《Chinese Business Review》 2023年第3期95-115,共21页
This study examines the effects of industrial parks on export earnings,employment creation,and FDI attraction in Ethiopia.Despite varying degrees of successes and failures,several countries have utilized industrial pa... This study examines the effects of industrial parks on export earnings,employment creation,and FDI attraction in Ethiopia.Despite varying degrees of successes and failures,several countries have utilized industrial park and other forms of special economic zones as a policy instrument for fostering economic transformation.China is at the forefront of using special economic zones as a policy tool for economic transformation.Ethiopia is one of the African countries that has adopted industrial park development as a policy tool to enhance its economic transformation.However,the issue is not well researched and this study aims to contribute to fill the research gap.The analysis of the hypotheses test reveals that industrial parks in Ethiopia have statistically significant effects on export earnings,employment creation,and FDI attraction with significant levels of p≤0.001.Low labor productivity,domestic raw material supply constraints,weak forward and backward linkage,transport cost and logistic constraints,and government institutions’capacity constraints are identified as the major constraints that affect the effectiveness of industrial parks and manufacturing firms.On the other hand,the availability of a trainable labor force,raw material potential,preferential policies and incentives,the economic growth of the country,and the labor wage rise in China and other emerging countries are identified as the main five potentials and opportunities for sustained and dynamic industrial parks development.Based on the findings,three policy implications are suggested.First,formulating and implementing manufacturing labor force development and utilization policies and strategies are vital.Second,the forward-backward linkage along the value chain needs to be enhanced through proper policies.Finally,institutional capacity building through learning by doing and public-private partnership has to be strengthened. 展开更多
关键词 industrial parks manufacturING export earnings employment creation FDI special economic zones
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Comparative analysis of breast and lung cancer survival rates and clinical trial enrollments among rural and urban patients in Georgia
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作者 TATIANA KURILO REBECCA D.PENTZ 《Oncology Research》 SCIE 2024年第9期1401-1406,共6页
Objectives:Rural patients have poor cancer outcomes and clinical trial(CT)enrollment compared to urban patients due to attitudinal,awareness,and healthcare access differential.Knowledge of cancer survival disparities ... Objectives:Rural patients have poor cancer outcomes and clinical trial(CT)enrollment compared to urban patients due to attitudinal,awareness,and healthcare access differential.Knowledge of cancer survival disparities and CT enrollment is important for designing interventions and innovative approaches to address the stated barriers.The study explores the potential disparities in cancer survival rates and clinical trial enrollments in rural and urban breast and lung cancer patients.Our hypotheses are that for both cancer types,urban cancer patients will have longer 5-year survival rates and higher enrollment rates in clinical trials than those in rural counties.Methods:We compared breast and lung cancer patients’survival rates and enrollment ratios in clinical trials between rural(RUCC 4-9)and urban counties in Georgia at a Comprehensive Cancer Center(CCC).To assess these differences,we carried out a series of independent samples t-tests and Chi-Square tests.Results:The outcomes indicate comparable 5-year survival rates across rural and urban counties for breast and lung cancer patients,failing to substantiate our hypothesis.While clinical trial enrollment rates demonstrated a significant difference between breast and lung cancer patients at CCC,no significant variation was observed based on rural or urban classification.Conclusion:These findings underscore the need for further research into the representation of rural patients with diverse cancer types at CCC and other cancer centers.Further,the findings have considerable implications for the initiation of positive social change to improve CT participation and reduce cancer survival disparities. 展开更多
关键词 CANCER Cancer survival rates Clinical trial enrollment Rural patients Health disparities Barriers to clinical trial participation Geographic disparities
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