This work proposes to study the effective elastic properties(EEP)of a wood-plastic composite(WPC)made from polyethylene terephthalate(PET)and Chilean Radiate pine’s wood our,using nite element simulations of a repres...This work proposes to study the effective elastic properties(EEP)of a wood-plastic composite(WPC)made from polyethylene terephthalate(PET)and Chilean Radiate pine’s wood our,using nite element simulations of a representative volume element(RVE)with periodic boundary conditions.Simulations are validated through a static 3-point bending test,with specimens obtained by extruding and injection.The effect of different weight fractions,space orientations and sizes of particles are here examined.Numerical predictions are empirically conrmed in the sense that composites with more wood our content and bigger size,have higher elastic modulus.However,these results are very sensitive to the orientation of particles.Voigt and Reuss mean-eld homogenisation approaches are also given as upper and lower limits.Experimental tests evidence that exural strengths and ultimate tensile elongations decrease respect to 100%PET,but these properties can be enhanced considering particle-size distributions instead of a xed size of wood our.展开更多
Most civil engineering structures are formed using a number of materials that are bonded to each other with their surface-to-surface interaction playing key role on the overall response of the structure. Unfortunately...Most civil engineering structures are formed using a number of materials that are bonded to each other with their surface-to-surface interaction playing key role on the overall response of the structure. Unfortunately these interactions are extremely variable;simplified and extremely detailed models trialed to date prove quite complex. Models that assume perfect interaction, on the other hand, predict unsafe behavior. In this paper a damage mechanics based interaction between two materials of different softening properties is developed using homogenisation approach. This paper describes the process of developing a bi-material representative volume element (RVE) using damaged homogenisation approach. The novelty in this paper is the development of non-local transient damage identification algorithm. Numerical examples prove the stability of the approach for a simplified RVE and encourage application to other shapes of RVEs.展开更多
The 7xxx series alloys are heat treatable wrought aluminium alloys based on the Al-Zn-Mg（-Cu） system. They are widely used in high-performance structural aerospace and transportation applications. Apart from composi...The 7xxx series alloys are heat treatable wrought aluminium alloys based on the Al-Zn-Mg（-Cu） system. They are widely used in high-performance structural aerospace and transportation applications. Apart from compositional, casting and thermo-mechanical processing effects, the balance of properties is also significantly influenced by the way in which the materials are heat-treated. This paper describes the effects of homogenisation, solution treatment, quenching and ageing treatments on the evolution of the microstructure and properties of some important medium to high-strength 7xxx alloys. With a focus on recent work at Monash University, where the whole processing route from homogenisation to final ageing has been studied for thick plate products, it is reported how microstructural features such as dispersoids, coarse constituent particles, fine-scale precipitates, grain structure and grain boundary characteristics can be controlled by heat treatment to achieve improved microstructure-property combinations. In particular, the paper presents methods for dissolving unwanted coarse constituent particles by controlled high- temperature treatments, quench sensitivity evaluations based on a systematic study of continuous cooling precipitation behaviour, and ageing investigations of one-, two- and three-step ageing treatments using experimental and modelling approaches, in each case, the effects on both the microstructure and the resulting properties are discussed.展开更多
The paper gives an overview of approaches towards ecological networks throughout Europe. It does not intend to present a complete picture, but to highlight common developments within countries and regions and show com...The paper gives an overview of approaches towards ecological networks throughout Europe. It does not intend to present a complete picture, but to highlight common developments within countries and regions and show common principles and differences between countries and regions that have to be taken into account when developing a joint European initiative. Countries or regions that have not been included can be active in the same way, but information was not accessible to the authors for different reasons. This overview shows the comparable trends in decline of landscapes and the diversity in approaches to biodiversity conservation and nature conservation planning. Understanding the differences and common issues are of utmost importance to generalise common principles and to understand the way neighbours and other European partners approach problems.展开更多
In-situ alloying has the potential to combine the compositional flexibility of high entropy alloys(HEAs)and the advanced forming capability of laser powder bed fusion(LPBF).This study fundamentally investigated the el...In-situ alloying has the potential to combine the compositional flexibility of high entropy alloys(HEAs)and the advanced forming capability of laser powder bed fusion(LPBF).This study fundamentally investigated the elemental homogenisation and grain development in the in-situ alloying process of CoCrFeMnNi HEA,by analysing the basic units,i.e.,tracks and layers,and introducing Mn as an alloying element to the base Co Cr Fe Ni HEA.Different modelling methods were employed to predict meltpool dimensions,and the results indicated the dependence of the modelling on practical meltpool modes.Delimitation of elemental distribution was found in keyhole meltpools since an intensive flow was generated due to recoil pressure.The homogeneity of in-situ alloyed Mn in single tracks was insufficient whether operated in conduction mode or keyhole mode,which required remelting from adjacent tracks and following layers to promote homogenisation significantly.The preferred orientation in single tracks along scanning directions changed from<001>to<101>as the scanning speed increased,although the cross-sections were similar in size with identical linear energy density.Such preference can be inherited during the printing process and lead to different textures in three-layer samples.It was also observed that applying hatch spacing smaller than a half meltpool width could coarsen the grains in a layer.The results from this study provide structure-parameter correlations for future microstructural tailoring and manipulation.展开更多
Pterostilbene(PT),a lipid-soluble polyphenol known for its antioxidant,anticancer,and various other biological properties,holds potential as an active ingredient in cosmetics for its anti-wrinkle and skin-whitening ef...Pterostilbene(PT),a lipid-soluble polyphenol known for its antioxidant,anticancer,and various other biological properties,holds potential as an active ingredient in cosmetics for its anti-wrinkle and skin-whitening effects.However,its application is limited by its low water solubility and poor penetration through the stratum corneum.To address these limitations,this study initially prepared Pterostilbene nanoliposomes(PT-NLPs)using a high shear-microjet homogenization treatment method,because of the distinctive hydrophilic and hydrophilic properties of the liposomes.The stability under different storage conditions of the PT-NLPs was evaluated by investigating the alterations of the particle size,PDI,Zeta potential and surface morphology,combined with the test results of Lumisizer stability analyzer.Finally,the comprehensive performance of PT-NLPs was evaluated through in vitro dermal and transdermal testing,human testing,and instrument testing.The results showed that the PT-NLPs treated by the high shear-microjet homogenisation method proposed in this paper possessed a 1.7-fold increase in the retention performance compared with the free PT solution,and no penetration occurred on the blood-brain barrier,indicating that PT-NLPs would not cause toxicity to the organism.The human efficacy evaluation found that the PT-NLPs whitening serum could improve skin dullness,brighten skin tone,and improve skin sensitivity after 14 days of use.The high shear-microjet homogenisation method proposed in this paper for the treatment of PT-NLPs improved the transdermal delivery properties of PT.The process has a broad application prospect in the fields of medicine and cosmetics.展开更多
In this paper,we describe and analyze two datasets entitled“Homogenised monthly and daily temperature and precipitation time series in China during 1960–2021”and“Homogenised monthly and daily temperature and preci...In this paper,we describe and analyze two datasets entitled“Homogenised monthly and daily temperature and precipitation time series in China during 1960–2021”and“Homogenised monthly and daily temperature and precipitation time series in Greece during 1960–2010”.These datasets provide the homogenised monthly and daily mean(TG),minimum(TN),and maximum(TX)temperature and precipitation(RR)records since 1960 at 366 stations in China and 56stations in Greece.The datasets are available at the Science Data Bank repository and can be downloaded from https://doi.org/10.57760/sciencedb.01731 and https://doi.org/10.57760/sciencedb.01720.For China,the regional mean annual TG,TX,TN,and RR series during 1960–2021 showed significant warming or increasing trends of 0.27℃(10 yr)^(-1),0.22℃(10 yr)^(-1),0.35℃(10 yr)^(-1),and 6.81 mm(10 yr)-1,respectively.Most of the seasonal series revealed trends significant at the 0.05level,except for the spring,summer,and autumn RR series.For Greece,there were increasing trends of 0.09℃(10 yr)-1,0.08℃(10 yr)^(-1),and 0.11℃(10 yr)^(-1)for the annual TG,TX,and TN series,respectively,while a decreasing trend of–23.35 mm(10 yr)^(-1)was present for RR.The seasonal trends showed a significant warming rate for summer,but no significant changes were noted for spring(except for TN),autumn,and winter.For RR,only the winter time series displayed a statistically significant and robust trend[–15.82 mm(10 yr)^(-1)].The final homogenised temperature and precipitation time series for both China and Greece provide a better representation of the large-scale pattern of climate change over the past decades and provide a quality information source for climatological analyses.展开更多
In this study,the functional gradient materials(FGMs)were the first attempt to homogenise the electric field distribution in the cable accessory,where zinc oxide particles(ZnO_(k))were filled into ethylene propylene d...In this study,the functional gradient materials(FGMs)were the first attempt to homogenise the electric field distribution in the cable accessory,where zinc oxide particles(ZnO_(k))were filled into ethylene propylene diene monomer with the composi-tionally gradient distribution using laminating and hot-pressing methods.The constructed FGMs with significantly improved non-linear conductivity can avoid the electric field distortion in cable accessories.The results show that the configuration of compositionally gradient structured fillers can significantly improve the electrical conductivity of FGMs compared to the homogeneous distribution.Additionally,compositionally gradient structures of ZnOk fillers can also improve the thermal conductivity of FGM composites,which facilitates the heat dissipation of dielectric and reduces the probability of electrothermal coupling breakdown.The mechanical properties of the composites are deeply affected by the filler's content and configuration,both improved tear elongation and tensile strength can be achieved at an optimal content and gradient structure of ZnOk fillers.Finally,the simulation analysis results show that FGM composites can homogenise the electric field more efficiently in comparison with homogeneous composites.This work demonstrates that compositionally gradient structures can improve the utilisation of functional fillers and develop the FGM composites for high-voltage direct current cable accessory applications.展开更多
We study the r-convergence of a class of 'parabolic' integral functionals for which the integrand f(z/,u/,Du) is allowed to satisfy a non-coercive assumption. Our results, restricted to the 'elliptic' ...We study the r-convergence of a class of 'parabolic' integral functionals for which the integrand f(z/,u/,Du) is allowed to satisfy a non-coercive assumption. Our results, restricted to the 'elliptic' case, generalize the main results of paper [7-8] and give an answer to an open problem in them.展开更多
A method to precipitate nanoparticles using a miniemulsion technique is described, in which miniemulsion droplets between 100 and 1000 nm in size serve as nanoreactors enabling both the control of particle formation a...A method to precipitate nanoparticles using a miniemulsion technique is described, in which miniemulsion droplets between 100 and 1000 nm in size serve as nanoreactors enabling both the control of particle formation and particle growth. The application of miniemulsion droplets to synthesise nanoparticles comprises three advantages： first, the size of the precipitated particles is limited by the reactant concentration within the emulsion droplet; second, particle agglomeration is prevented as nanoparticle collision outside the nanoreactor is avoided; and third, easy technical scale up can be realized by increasing emulsion volume and thus the number of nanoreactors, while local conditions within the reactors are not changed, The miniemulsion technique is an easy scalable process which allows defined synthesis of particles by precipitation reactions. The miniemulsion technique involves first the preparation of a stable water-in- oil miniemulsion by high pressure homogenisation. Whereas a water soluble reactant is provided within the aqueous droplets, another oilas well as water-soluble reactant can be introduced to the emulsion after homogenisation. The precipitation reaction is induced by the diffusion of the second reactant into the emulsion droplet. Together with this contribution, a method is described and discussed which uses a high pressure homogenisation process to produce stable water-in-oil miniemulsions serving as a reaction medium to precipitate metal oxides.展开更多
基金support from the Chilean Regional Government of Maule through the FIC-R project“Valorization of recycled waste through the creation of new materials for the manufacture of marketable products”,code BIP 30.481.945。
文摘This work proposes to study the effective elastic properties(EEP)of a wood-plastic composite(WPC)made from polyethylene terephthalate(PET)and Chilean Radiate pine’s wood our,using nite element simulations of a representative volume element(RVE)with periodic boundary conditions.Simulations are validated through a static 3-point bending test,with specimens obtained by extruding and injection.The effect of different weight fractions,space orientations and sizes of particles are here examined.Numerical predictions are empirically conrmed in the sense that composites with more wood our content and bigger size,have higher elastic modulus.However,these results are very sensitive to the orientation of particles.Voigt and Reuss mean-eld homogenisation approaches are also given as upper and lower limits.Experimental tests evidence that exural strengths and ultimate tensile elongations decrease respect to 100%PET,but these properties can be enhanced considering particle-size distributions instead of a xed size of wood our.
文摘Most civil engineering structures are formed using a number of materials that are bonded to each other with their surface-to-surface interaction playing key role on the overall response of the structure. Unfortunately these interactions are extremely variable;simplified and extremely detailed models trialed to date prove quite complex. Models that assume perfect interaction, on the other hand, predict unsafe behavior. In this paper a damage mechanics based interaction between two materials of different softening properties is developed using homogenisation approach. This paper describes the process of developing a bi-material representative volume element (RVE) using damaged homogenisation approach. The novelty in this paper is the development of non-local transient damage identification algorithm. Numerical examples prove the stability of the approach for a simplified RVE and encourage application to other shapes of RVEs.
基金The Aluminium Corporation of China Ltd.(Chalco)for supporting aspects of this work financiallyproviding AA7150 materials as part of the Australia-China International Centre for Light Alloy Research(ICLAR)+1 种基金Monash University for developing the retrogression and reageing Matlab model (as part of the PhD project of Dr Adrian GROSVENOR)The ARC Centre of Excellence for Design in Light Metals and its Directors (first Prof Barry MUDDLE and then Prof Xin-hua WU) for supporting
文摘The 7xxx series alloys are heat treatable wrought aluminium alloys based on the Al-Zn-Mg（-Cu） system. They are widely used in high-performance structural aerospace and transportation applications. Apart from compositional, casting and thermo-mechanical processing effects, the balance of properties is also significantly influenced by the way in which the materials are heat-treated. This paper describes the effects of homogenisation, solution treatment, quenching and ageing treatments on the evolution of the microstructure and properties of some important medium to high-strength 7xxx alloys. With a focus on recent work at Monash University, where the whole processing route from homogenisation to final ageing has been studied for thick plate products, it is reported how microstructural features such as dispersoids, coarse constituent particles, fine-scale precipitates, grain structure and grain boundary characteristics can be controlled by heat treatment to achieve improved microstructure-property combinations. In particular, the paper presents methods for dissolving unwanted coarse constituent particles by controlled high- temperature treatments, quench sensitivity evaluations based on a systematic study of continuous cooling precipitation behaviour, and ageing investigations of one-, two- and three-step ageing treatments using experimental and modelling approaches, in each case, the effects on both the microstructure and the resulting properties are discussed.
文摘The paper gives an overview of approaches towards ecological networks throughout Europe. It does not intend to present a complete picture, but to highlight common developments within countries and regions and show common principles and differences between countries and regions that have to be taken into account when developing a joint European initiative. Countries or regions that have not been included can be active in the same way, but information was not accessible to the authors for different reasons. This overview shows the comparable trends in decline of landscapes and the diversity in approaches to biodiversity conservation and nature conservation planning. Understanding the differences and common issues are of utmost importance to generalise common principles and to understand the way neighbours and other European partners approach problems.
基金financially supported by the Research and Development Program Project in Key Areas of Guangdong Province(No.2019B090907001)the Shenzhen Science and Technology Innovation Commission(Nos.JCYJ20180504165824643 and JSGG20210420091802007)the National Natural Science Foundation of China(Nos.51971108 and U19A2085)。
文摘In-situ alloying has the potential to combine the compositional flexibility of high entropy alloys(HEAs)and the advanced forming capability of laser powder bed fusion(LPBF).This study fundamentally investigated the elemental homogenisation and grain development in the in-situ alloying process of CoCrFeMnNi HEA,by analysing the basic units,i.e.,tracks and layers,and introducing Mn as an alloying element to the base Co Cr Fe Ni HEA.Different modelling methods were employed to predict meltpool dimensions,and the results indicated the dependence of the modelling on practical meltpool modes.Delimitation of elemental distribution was found in keyhole meltpools since an intensive flow was generated due to recoil pressure.The homogeneity of in-situ alloyed Mn in single tracks was insufficient whether operated in conduction mode or keyhole mode,which required remelting from adjacent tracks and following layers to promote homogenisation significantly.The preferred orientation in single tracks along scanning directions changed from<001>to<101>as the scanning speed increased,although the cross-sections were similar in size with identical linear energy density.Such preference can be inherited during the printing process and lead to different textures in three-layer samples.It was also observed that applying hatch spacing smaller than a half meltpool width could coarsen the grains in a layer.The results from this study provide structure-parameter correlations for future microstructural tailoring and manipulation.
基金supported by the Guangdong Provincial University Key Area Project[grant numbers 2023ZDZX4136]the Guangdong Provincial University Innovation Team Project[grant numbers 2023KCXTD085]+1 种基金the Guangdong Provincial Science and Technology Innovation Strategy Special Fund[grant numbers pdjh2022b1046]the Student Scientific Research Project of Jiangmen Polytechnic[grant numbers jzxsky20230102]。
文摘Pterostilbene(PT),a lipid-soluble polyphenol known for its antioxidant,anticancer,and various other biological properties,holds potential as an active ingredient in cosmetics for its anti-wrinkle and skin-whitening effects.However,its application is limited by its low water solubility and poor penetration through the stratum corneum.To address these limitations,this study initially prepared Pterostilbene nanoliposomes(PT-NLPs)using a high shear-microjet homogenization treatment method,because of the distinctive hydrophilic and hydrophilic properties of the liposomes.The stability under different storage conditions of the PT-NLPs was evaluated by investigating the alterations of the particle size,PDI,Zeta potential and surface morphology,combined with the test results of Lumisizer stability analyzer.Finally,the comprehensive performance of PT-NLPs was evaluated through in vitro dermal and transdermal testing,human testing,and instrument testing.The results showed that the PT-NLPs treated by the high shear-microjet homogenisation method proposed in this paper possessed a 1.7-fold increase in the retention performance compared with the free PT solution,and no penetration occurred on the blood-brain barrier,indicating that PT-NLPs would not cause toxicity to the organism.The human efficacy evaluation found that the PT-NLPs whitening serum could improve skin dullness,brighten skin tone,and improve skin sensitivity after 14 days of use.The high shear-microjet homogenisation method proposed in this paper for the treatment of PT-NLPs improved the transdermal delivery properties of PT.The process has a broad application prospect in the fields of medicine and cosmetics.
基金funded by the Hellenic and Chinese Governments,in the frame of the Greek-Chinese R&T Cooperation Programme project“Comparative study of extreme climate indices in China and Europe/Greece,based on homogenised daily observations—CLIMEX”(Contract T7ΔKI-00046)the National Key Technologies Research and Development Program“Comparative study of changing climate extremes between China and Europe/Greece based on homogenised daily observations”(Grant No.2017YFE0133600)。
文摘In this paper,we describe and analyze two datasets entitled“Homogenised monthly and daily temperature and precipitation time series in China during 1960–2021”and“Homogenised monthly and daily temperature and precipitation time series in Greece during 1960–2010”.These datasets provide the homogenised monthly and daily mean(TG),minimum(TN),and maximum(TX)temperature and precipitation(RR)records since 1960 at 366 stations in China and 56stations in Greece.The datasets are available at the Science Data Bank repository and can be downloaded from https://doi.org/10.57760/sciencedb.01731 and https://doi.org/10.57760/sciencedb.01720.For China,the regional mean annual TG,TX,TN,and RR series during 1960–2021 showed significant warming or increasing trends of 0.27℃(10 yr)^(-1),0.22℃(10 yr)^(-1),0.35℃(10 yr)^(-1),and 6.81 mm(10 yr)-1,respectively.Most of the seasonal series revealed trends significant at the 0.05level,except for the spring,summer,and autumn RR series.For Greece,there were increasing trends of 0.09℃(10 yr)-1,0.08℃(10 yr)^(-1),and 0.11℃(10 yr)^(-1)for the annual TG,TX,and TN series,respectively,while a decreasing trend of–23.35 mm(10 yr)^(-1)was present for RR.The seasonal trends showed a significant warming rate for summer,but no significant changes were noted for spring(except for TN),autumn,and winter.For RR,only the winter time series displayed a statistically significant and robust trend[–15.82 mm(10 yr)^(-1)].The final homogenised temperature and precipitation time series for both China and Greece provide a better representation of the large-scale pattern of climate change over the past decades and provide a quality information source for climatological analyses.
基金National Engineering Research Center of UHV Technology and Novel Electrical Equipment Basis,Grant/Award Number:NERCUHV-2023-KF-02。
文摘In this study,the functional gradient materials(FGMs)were the first attempt to homogenise the electric field distribution in the cable accessory,where zinc oxide particles(ZnO_(k))were filled into ethylene propylene diene monomer with the composi-tionally gradient distribution using laminating and hot-pressing methods.The constructed FGMs with significantly improved non-linear conductivity can avoid the electric field distortion in cable accessories.The results show that the configuration of compositionally gradient structured fillers can significantly improve the electrical conductivity of FGMs compared to the homogeneous distribution.Additionally,compositionally gradient structures of ZnOk fillers can also improve the thermal conductivity of FGM composites,which facilitates the heat dissipation of dielectric and reduces the probability of electrothermal coupling breakdown.The mechanical properties of the composites are deeply affected by the filler's content and configuration,both improved tear elongation and tensile strength can be achieved at an optimal content and gradient structure of ZnOk fillers.Finally,the simulation analysis results show that FGM composites can homogenise the electric field more efficiently in comparison with homogeneous composites.This work demonstrates that compositionally gradient structures can improve the utilisation of functional fillers and develop the FGM composites for high-voltage direct current cable accessory applications.
文摘We study the r-convergence of a class of 'parabolic' integral functionals for which the integrand f(z/,u/,Du) is allowed to satisfy a non-coercive assumption. Our results, restricted to the 'elliptic' case, generalize the main results of paper [7-8] and give an answer to an open problem in them.
基金supported by BASF SE within the scope of preliminary work for the JointLab IP3, a research initiative of BASF SE and Karlsruhe Institute of Technology (KIT)
文摘A method to precipitate nanoparticles using a miniemulsion technique is described, in which miniemulsion droplets between 100 and 1000 nm in size serve as nanoreactors enabling both the control of particle formation and particle growth. The application of miniemulsion droplets to synthesise nanoparticles comprises three advantages： first, the size of the precipitated particles is limited by the reactant concentration within the emulsion droplet; second, particle agglomeration is prevented as nanoparticle collision outside the nanoreactor is avoided; and third, easy technical scale up can be realized by increasing emulsion volume and thus the number of nanoreactors, while local conditions within the reactors are not changed, The miniemulsion technique is an easy scalable process which allows defined synthesis of particles by precipitation reactions. The miniemulsion technique involves first the preparation of a stable water-in- oil miniemulsion by high pressure homogenisation. Whereas a water soluble reactant is provided within the aqueous droplets, another oilas well as water-soluble reactant can be introduced to the emulsion after homogenisation. The precipitation reaction is induced by the diffusion of the second reactant into the emulsion droplet. Together with this contribution, a method is described and discussed which uses a high pressure homogenisation process to produce stable water-in-oil miniemulsions serving as a reaction medium to precipitate metal oxides.
