Article
Electrochemistry
Giampaolo Lacarbonara, Morteza Rahmanipour, Juri Belcari, Lorenzo Lodi, Andrea Zucchelli, Catia Arbizzani
Summary: A new equipment for in situ electrochemical dilatometry is designed and validated by studying the volumetric changes of a model electrode. The contactless measurement system allows for testing without influencing sample dilation, and different forces can be applied within a selected range. Graphite is used as a model electrode, and electrochemical tests in various electrolytes under different applied forces reveal insights into lithium insertion/deinsertion processes and related phenomena.
ELECTROCHIMICA ACTA
(2021)
Review
Chemistry, Multidisciplinary
Lin Zhang, Xingyu Li, Xuanhui Qu, Mingli Qin, Zhongyou Que, Zichen Wei, Chenguang Guo, Xin Lu, Yanhao Dong
Summary: Ultrafine-grained (UFG) refractory metals are promising materials for various applications, but achieving full density while maintaining a fine microstructure through sintering remains challenging. This article provides an overview of sintering issues, microstructural design rules, and powder metallurgy practices for UFG and nanocrystalline refractory metals. It also reviews previous efforts, including the use of fine/nanopowders and field-assisted sintering techniques, and highlights the recent technological breakthrough of pressureless two-step sintering for producing dense UFG refractory metals. Additionally, the progress of powder metallurgy in specific materials systems, such as elementary metals and refractory alloys, is discussed, and future developments towards UFG and nanocrystalline refractory metals with improved properties are outlined.
ADVANCED MATERIALS
(2023)
Article
Environmental Sciences
Sandhya Mishra, Yaohua Huang, Jiayi Li, Xiaozhen Wu, Zhe Zhou, Qiqi Lei, Pankaj Bhatt, Shaohua Chen
Summary: Biofilm-mediated bioremediation is an effective approach for the elimination of environmental pollutants due to the biofilm's ability to degrade and absorb contaminants. Biofilm communities exhibit high tolerance to pollutants and can metabolize or degrade organic pollutants and heavy metals through the regulation of gene expression.
Review
Engineering, Environmental
Sandhya Mishra, Ziqiu Lin, Shimei Pang, Yuming Zhang, Pankaj Bhatt, Shaohua Chen
Summary: Heavy metal toxicity is a pressing ecological issue affecting ecosystems, with conventional approaches being unsuitable for remediation due to environmental concerns. Biosurfactant-based bioremediation offers a promising, sustainable solution with potential for effective removal of heavy metal pollutants.
JOURNAL OF HAZARDOUS MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
Chunquan Liu, Xianhua Chen, Yaobo Hu, Wei Zhang, Yusheng Zhang, Jianbo Li, Fusheng Pan
Summary: This study prepares a gradient ultrafine-grained structure on the surface of a magnesium alloy using sliding friction treatment. The new material exhibits significantly improved yield strength and excellent ductility compared to homogeneous structures. Transmission electron microscopy and electron backscatter diffraction analyses reveal that the refined grain structure and grain orientation modification contribute to the enhanced plastic deformation ability.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2022)
Article
Materials Science, Multidisciplinary
M. Haghpanah, A. Esmaeilnia, M. R. Sabour, E. Taherkhani, M. Mosavi Mashhadi, G. Faraji
Summary: In this study, hydrostatic twist extrusion (HTE) was used to process long ultrafine grained (UFG) bulk samples. The use of high-pressure fluid eliminated surface contact between die and sample. The HTE process resulted in a reduction in grain size and an improvement in mechanical properties of the aluminum samples. The process shows promise for future industrial applications.
Article
Materials Science, Multidisciplinary
Yungang Nie, Yanjun Wu, Rong Zhu
Summary: This paper investigated the low cycle fatigue properties of ultrafine-grained Cu with equiaxed or lamellar grains. Although the lamellar grained structure shows higher cyclic softening than the equiaxed one, it exhibits a lowcyclic fatigue life improvement. This contradictory can be explained by the homogeneously distributed cyclic damage in the lamellar grained structure which presents a rotational dynamic recrystallization-led grain refinement and the significant intersecting shear bands during low cyclic fatigue.
Article
Materials Science, Multidisciplinary
Zhongyou Que, Zichen Wei, Xingyu Li, Lin Zhang, Yanhao Dong, Mingli Qin, Junjun Yang, Xuanhui Qu, Ju Li
Summary: In this study, the challenge of sintering ultrafine-grained refractory metals and alloys to full density was addressed using pressureless two-step sintering in tungsten-rhenium alloy and pure molybdenum. The results showed that properly processed nano powders enabled high-density sintering while maintaining fine grain sizes, leading to better microstructural uniformity and improved mechanical properties.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2022)
Article
Materials Science, Multidisciplinary
Huizi Chen, Jian Wang, Xiangchen Meng, Yuming Xie, Yulong Li, Long Wan, Yongxian Huang
Summary: Utilizing friction stir processing, an ultrafine-grained structure was achieved in Mg-Zn-Y-Zr alloy leading to extraordinary superplasticity. Grain refinement and homogeneous dispersion of precipitates were promoted by the coupled thermo-mechanical effect, resulting in an ultra-fined grains size of 1.9 +/- 0.4 μm and a superplastic elongation of 642%. Grain boundary sliding was considered as the predominant superplastic deformation mechanism in ultrafine-grained materials.
Article
Materials Science, Multidisciplinary
Michael Wurmshuber, Severin Jakob, Simon Doppermann, Stefan Wurster, Rishi Bodlos, Lorenz Romaner, Verena Maier-Kiener, Daniel Kiener
Summary: Tungsten is often considered for high-performance applications in harsh environments due to its high strength and good physical properties. However, its inherent brittleness and low ductility hinder its successful deployment. This study attempts to improve the ductility of ultrafine-grained tungsten by increasing the grain boundary cohesion through doping elements. The results show that the addition of boron and hafnium significantly increases the bending strength and ductility of ultrafine-grained tungsten. Additional heat treatment further enhances the strength and overall mechanical properties of the material.
Review
Immunology
Ziyin Chen, Ziqi Yue, Ronghua Wang, Kaiqi Yang, Shenglong Li
Summary: Cancer is the leading cause of death worldwide and a major obstacle to increasing life expectancy. Recent developments in nanotechnology have brought breakthroughs in cancer immunotherapy, using engineered nanomaterials to trigger specific tumor-killing effects and improve immune cell infiltration into metastatic lesions, leading to a more effective immune response and preventing metastasis and tumor recurrence.
FRONTIERS IN IMMUNOLOGY
(2022)
Review
Materials Science, Multidisciplinary
Deliang Zhang
Summary: Ultrafine grained metals and metal matrix nanocomposites with enhanced strength and good tensile ductility can be successfully fabricated through processing and consolidation techniques. The synergistic effects of grain boundary strengthening and intragranular nanoparticles play a crucial role in improving the material's performance, while heterogeneous microstructures introduce additional boundaries between hard and soft regions to enhance strength without sacrificing ductility.
PROGRESS IN MATERIALS SCIENCE
(2022)
Review
Materials Science, Multidisciplinary
Deliang Zhang
Summary: This paper reviews the successful fabrication of ultrafine grained metals and metal matrix nanocomposites with enhanced strength and good tensile ductility through processing and thermomechanical consolidation of powders. The synergistic effects of grain boundary strengthening and intragranular ceramic nanoparticles are highlighted as crucial for significantly improving tensile yield strength while maintaining good tensile ductility. The introduction of extra boundaries between hard and soft regions in the material's microstructure further enhances strength without sacrificing ductility, although it requires careful management to prevent weakening effects on the hard regions.
PROGRESS IN MATERIALS SCIENCE
(2021)
Article
Multidisciplinary Sciences
Dangquan Zhang, Zhiyong Zhang, Turgay Unver, Baohong Zhang
Summary: CRISPR/Cas system is a powerful biotechnological tool for precise gene editing and crop improvement. Although widely used, there are still challenges and future directions for further development in the field.
JOURNAL OF ADVANCED RESEARCH
(2021)
Article
Materials Science, Multidisciplinary
D. Bhuyan, R. K. Pandey, S. N. Ojha, G. V. S. Sastry, H. Choudhary, A. Sharma, R. Manna
Summary: Low carbon steel deformed by ECAP can be further processed with electropulsing to enhance ductility by refining grain structure and recovering dislocation defects. This trade-off between strength and ductility results in a bimodal grain size distribution that accommodates larger deformations and improves overall ductility.
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
(2021)
Article
Nanoscience & Nanotechnology
M. Goessler, S. Topolovec, H. Krenn, R. Wuerschum
Summary: The use of hydrogen atoms for magneto-ionic applications has shown benefits of high switching speed and large changes in magnetic moment. Testing the influence of hydrogen intercalation on magnetism in nanoporous Pd(1-x)Cox reveals insights into the interaction of hydrogen with magnetic clusters. The large magnetic switching effects obtained upon hydrogen-charging at room temperature open up new possibilities for real-life applications in magnetic devices.
Article
Materials Science, Paper & Wood
Laura Resch, Anna Karner, Wolfgang Sprengel, Roland Wuerschum, Robert Schennach
Summary: This study applied the experimental technique of positron annihilation lifetime spectroscopy (PALS) to monitor the microstructural changes of cellulose-based materials, such as paper, during water intake. Results showed that the mean positron lifetime increased with time in humid atmosphere, with different trends depending on the type of cellulose sample. The study demonstrated that water transport in paper can be reliably followed over a long timespan using PALS, and even distinguish between different types of cellulose materials based on the observed changes in positron lifetime.
Article
Chemistry, Physical
Markus Goessler, Elisabeth Hengge, Marco Bogar, Mihaela Albu, Daniel Knez, Heinz Amenitsch, Roland Wuerschum
Summary: This study investigates the evolution of nanoporosity in the electrochemical dealloying process for both CoPd and AgAu alloys. The results show that the dealloying front progresses more rapidly for CoPd and the nanoporous structure of Pd coarsens considerably slower compared to Au.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Metallurgy & Metallurgical Engineering
Roland Wuerschum, Robert Weitenhueller, Robert Enzinger, Wolfgang Sprengel
Summary: A model is presented to derive both vacancy formation and migration characteristics from length change measurements upon modulated time-linear heating, suitable for materials with high thermal vacancy concentrations and low vacancy diffusivities.
INTERNATIONAL JOURNAL OF MATERIALS RESEARCH
(2022)
Article
Materials Science, Multidisciplinary
Roland Wuerschum
Summary: Direct determination of mean diffusion times by Laplace transform is advantageous in obtaining closed-form expressions for diffusion and reaction-limited loading and unloading of species. This method is particularly useful for complex cases where inverse Laplace transform calculations become laborious. The concept of mean load-ing or unloading time is compared with other time constants, such as mean action time or time lag.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2023)
Article
Chemistry, Physical
Philipp Brunner, Eva-Maria Steyskal, Stefan Topolovec, Roland Wuerschum
Summary: The positronium chemistry of a Fe2+/3+ solution was studied using a novel approach of positronium electrochemistry. The oxidation and reduction reactions were precisely monitored by positron lifetime, and the asymmetric behavior of positron lifetime variation with applied potential was explained by the influence of Fe3+ on positronium formation and annihilation. This study highlights the potential application of positronium electrochemistry for in situ studies of iron-based redox-flow battery electrolytes.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Elisabeth Hengge, Jakob Ihrenberger, Eva-Maria Steyskal, Ricardo Buzolin, Martin Luckabauer, Christof Sommitsch, Roland Wuerschum
Summary: The synthesis of bulk nanoporous copper from a copper-manganese alloy by electrochemical dealloying and free corrosion, as well as the electrochemical behavior and oxide formation of the dealloyed structures, have been investigated. The nanoporous copper exhibited suppressed reordering processes and the formation of a hybrid composite of copper and manganese oxide on its surface. This unique heterogeneous structure shows potential for applications in energy storage and catalysis.
NANOSCALE ADVANCES
(2023)
Article
Chemistry, Physical
Florian Brumbauer, Ulrich Brossmann, Robert Enzinger, Jiehua Li, Wolfgang Sprengel, Roland Wuerschum
Summary: Micro-alloying is an important approach in designing modern Al-based alloys, affecting precipitation kinetics during heat treatment and optimizing microstructure. This study uses difference dilatometry to investigate precipitation processes in Al-1.7Cu alloys with varying Au content. The analysis provides a quantitative understanding of the formation of metastable-precipitate phase (Al2Cu) and its transformation to the stable 0-precipitate phase (Al2Cu) through time-linear heating. The study shows that micro-alloying with Au promotes the 0-formation by increasing nucleation and growth rate.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Physical
Philipp Brunner, Eva-Maria Steyskal, Roland Wurschum
Summary: This study successfully demonstrated the switching of positronium triplet quenching through electrochemical means in an aqueous K-3[Fe(CN)(6)] electrolyte. Dynamic in situ measurements showed highly reversible substantial variations of the mean positron lifetime tau(m) during the electrochemical switching between the oxidation states Fe(CN)(6)(3-) and Fe(CN)(6)(4-).
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Chemistry, Physical
Elisabeth Hengge, Markus Hirber, Philipp Brunner, Eva-Maria Steyskal, Bernd Nidetzky, Roland Wuerschum
Summary: The electrochemical behavior of nanoporous gold modified with self-assembled monolayers was investigated, with long-chain MHDA showing the most distinct point of zero charge for precise charge control. Proton transfer reaction studies indicated an increased fraction of electrochemically controllable SAMs compared to planar electrodes, suggesting attractive application potential.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Materials Science, Biomaterials
Philipp Brunner, Florian Brumbauer, Eva-Maria Steyskal, Oliver Renk, Annelie-Martina Weinberg, Hartmuth Schroettner, Roland Wuerschum
Summary: The study reveals that high-pressure torsion significantly reduces the corrosion resistance of Mg-0.45wt%Zn-0.45wt%Ca alloy, resulting in the formation of larger open-volume structures during corrosion, possibly related to hydrogen.
BIOMATERIALS SCIENCE
(2021)
