Article
Multidisciplinary Sciences
Shufen Chu, Pan Liu, Yin Zhang, Xiaodong Wang, Shuangxi Song, Ting Zhu, Ze Zhang, Xiaodong Han, Baode Sun, Mingwei Chen
Summary: In this study, the authors report real-time atomic-scale observations of grain boundary dislocation climb in nanostructured gold at room temperature. The climb of a dislocation is found to occur through stress-induced reconstruction of neighboring atomic columns. The proposed atomic route of dislocation climb is energetically favorable, as demonstrated by Monte Carlo simulations. The in situ observations also reveal the significance of grain boundary dislocation climb in controlling the microstructures and properties of nanostructured metals.
NATURE COMMUNICATIONS
(2022)
Article
Engineering, Mechanical
Chuanyang Lu, Peng Wang, Silu Zheng, Xijia Wu, Rong Liu, Yanming He, Jianguo Yang, Zengliang Gao, Shan-Tung Tu
Summary: To ensure the structural integrity of the nuclear reactor pressure vessel (RPV) during severe accidents, in-vessel retention (IVR) is essential for nuclear power generation as a carbon-neutral energy source. This study develops a simplified deformation-mechanism-based true-stress (DMTS) model to accurately predict the creep behavior and life of SA508 Gr.3 steel, a typical RPV material, above the phase transformation temperatures. Experimental observations show that the simplified DMTS model achieves excellent agreement with the predicted time to specific creep strain and rupture, compared to empirical methods such as Orr-Sherby-Dorn (OSD) and Larson-Miller (LM). Metallurgical examinations are conducted to discuss the controlling deformation mechanisms, providing a physical basis for the model development and application.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2023)
Article
Engineering, Mechanical
Le Xu, Run-Zi Wang, Ji Wang, Lei He, Takamoto Itoh, Hideo Miura, Xian-Cheng Zhang, Shan-Tung Tu
Summary: In this paper, strain-controlled fatigue and creep-fatigue tests were performed on type 304 stainless steel at 873 K, and subsequent metallographic observations were conducted. A viscoplasticity constitutive model and damage models were proposed to simulate the cyclic stress-strain responses and predict creep-fatigue damage evaluations. Good agreements were achieved between experimental data and simulated results.
INTERNATIONAL JOURNAL OF PLASTICITY
(2022)
Article
Thermodynamics
Y. P. Ding, X. J. Wu, R. Liu, X. Z. Zhang, F. Khelfaoui
Summary: The research uses the deformation-mechanism-based true-stress (DMTS) creep model to analyze short-term (<10000 h) creep test data for nickel-based alloy Haynes 282. The deformation mechanisms are described in terms of power-laws for grain boundary sliding (GBS), intragranular dislocation glide (IDG), and intragranular dislocation climb (IDC). The DMTS model can accurately describe the entire creep curve and predict the creep failure mode and rupture life of Haynes 282 with a high coefficient of determination R2 = 0.93.
THERMAL SCIENCE AND ENGINEERING PROGRESS
(2023)
Article
Chemistry, Multidisciplinary
Huan Yao, Tianzhou Ye, Pengfei Wang, Junmei Wu, Jing Zhang, Ping Chen
Summary: This study investigates the creep process of nanocrystalline FeCrAl alloys using atomistic simulations, and analyzes the dependence of creep on temperature, stress, and grain size. It is found that under low stress conditions, grain boundary diffusion contributes more to creep than lattice diffusion, while lattice diffusion controls creep in alloys with larger grain sizes. Under medium- and high-stress conditions, grain boundary slip and dislocation motion begin to control the creep mechanism.
Article
Chemistry, Physical
Yanju Wang, Xinhao Wang, Yanfeng Yang, Xiang Lan, Zhao Zhang, Heng Li
Summary: Low-cycle fatigue, creep and creep-fatigue tests of Ti2AlNb-based alloy were conducted at 550 degrees C, indicating that the introduction of creep damage can significantly affect the cycle life and failure mechanism of the alloy.
Article
Engineering, Mechanical
Mariyappan Arul Kumar, Laurent Capolungo
Summary: Predicting the effects of microstructure on high-temperature creep responses of steel components is critical to minimize the risks of failure and maximize economic viability in the energy sector. In this study, an advanced mechanistic constitutive model is used to investigate the influence of microstructure on creep responses and to explain the variability in the performance of grade-91 alloy. The model accurately predicts steady-state creep rates and primary-to-secondary transients for a wide range of creep conditions, and can also extrapolate the creep response of grade-91 alloy outside of the calibration regime. The study shows that the initial microstructure, characterized by grain size, dislocation density, and precipitate content, plays a significant role in the creep response, with the significance varying with stress and temperature. Comparing the model predictions with experimental data reveals that the differences in creep responses can be rationalized based on differences in the initial microstructure.
INTERNATIONAL JOURNAL OF PLASTICITY
(2022)
Article
Nanoscience & Nanotechnology
Yunsheng Wu, Xiangxiang Zhang, Changshuai Wang, Xuezhi Qin, Jieshan Hou, Lanzhang Zhou
Summary: The creep deformation behavior and microstructure evolution of the Ni-Fe-based GH984G alloy were investigated. The interaction between dislocation and gamma' precipitates is the main reason for the higher creep activation energy than lattice self-diffusion. Dislocation climbing is the primary creep mechanism below 800℃, while dislocation climbing and partial dislocation shearing into gamma' dominate above 800℃. Additionally, microstructural degradation also contributes to creep damage.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Chemistry, Physical
Stephen Okhiai Emokpaire, Nan Wang, Jide Liu, Chongwei Zhu, Xinguang Wang, Jinguo Li, Yizhou Zhou
Summary: This study investigates the effect of Ru element on the γ'-phase evolution and deformation mechanism in a fourth-generation Ni-based single-crystal superalloy. The results show that Ru element alters the distribution coefficient of other elements in the alloy, leading to a difference in microstructure compared to the alloy without Ru. Ru addition triggers the incubation period before primary creep stage and inhibits the slip system {111}<112> at medium-temperature and high-stress creep, resulting in a considerably low creep rate and high creep life for the Ru-containing alloy.
Article
Engineering, Geological
Linjian Ma, Yunxiao Wang, Mingyang Wang, Bing Xue, Liqun Duan
Summary: The mechanical performance of rock salt under combined creep and fatigue was investigated in this study. The strain-time curves show a three-phase S-shaped evolution, similar to what is seen in pure creep or fatigue tests. Stress dwelling periods may accelerate the accumulation of inelastic deformation and reduce the cycling life of rock salt. Additionally, micro-cracks primarily form during loading periods and grow stably during stress dwelling periods within a single loading cycle.
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2021)
Article
Materials Science, Multidisciplinary
Jian Ren, Liming Yu, Chenxi Liu, Zongqing Ma, Huijun Li, Zumin Wang, Yongchang Liu, Hui Wang
Summary: The study systematically investigated the creep properties, microstructural evolution, and fracture mechanism of 16Cr-3Al ODS steel under different uniaxial tensile stresses at 600 degrees C. The relationship between the minimum creep rate and mean creep rate was linear, with a determined threshold stress. The evolution of the Cr-rich phase played a significant role in the fracture mechanism of 16Cr-3Al ODS steel after creep deformation.
JOURNAL OF NUCLEAR MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Yue Wang, Li Shi, Chaoyu Han, Kejian Li, Zhipeng Cai, Haitao Wang
Summary: The study systematically investigated the creep rupture mechanisms of IN617 by establishing the relationship between microstructural characteristics and creep performance. Different rupture mechanisms were identified under various conditions, such as sliding and migration of recrystallized grain boundaries, creep voids along the grain boundaries, and microstructural degradation and internal oxidization, which ultimately accelerated creep rupture.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Review
Materials Science, Multidisciplinary
Weidong Li, Di Xie, Dongyue Li, Yong Zhang, Yanfei Gao, Peter K. Liaw
Summary: Research in high-entropy alloys has been booming since the 2010s, focusing on the vast potential in compositions, microstructures, and properties. Efforts are mainly directed towards exploring the compositional space and microstructures, as well as understanding the mechanical behavior. However, there is still a lack of comprehensive studies on the mechanical behavior of high-entropy alloys.
PROGRESS IN MATERIALS SCIENCE
(2021)
Article
Metallurgy & Metallurgical Engineering
Ying Han, Jiaqi Sun, Jiapeng Sun, Guoqing Zu, Weiwei Zhu, Xu Ran
Summary: By studying the creep behavior of the Fe-17Cr-1.2Cu-0.5Nb-0.01C ferritic heat-resistant stainless steel, it was found that as the temperature increased and the stress decreased, the softening of the metal matrix accelerated, leading to more prominent plastic flow. The creep process generated Cu-rich phases and Nb-rich Laves particles in co-existence, with characteristics of ductile fracture.
ACTA METALLURGICA SINICA-ENGLISH LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Kumar Sourabh, J. B. Singh
Summary: The creep behavior of Ni-base superalloy 690 was studied under constant load creep conditions at temperatures ranging from 800 to 1000 ℃ and stresses ranging from 25 to 105 MPa. The alloy exhibited power-law creep behavior and followed the Monkman-Grant relationship. The majority of creep data points fell within a +/- 5% scatter band on the Larson Miller parameter vs. log stress plot. The alloy underwent more than 50% of its life in the tertiary creep regime and predominantly failed due to cavitation. The apparent activation energy and stress exponent of creep were relatively high.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2022)
Article
Neurosciences
Frantisek Vasa, Harriet Hobday, Ryan A. Stanyard, Richard E. Daws, Vincent Giampietro, Owen O'Daly, David J. Lythgoe, Jakob Seidlitz, Stefan Skare, Steven C. R. Williams, Andre F. Marquand, Robert Leech, James H. Cole
Summary: Current neuroimaging acquisition and processing approaches focus on quality over speed, but rapid processing of neuroimaging data can lead to new paradigms such as adaptive acquisition. This study evaluated the impact of rapid processing on manually labelled T-1-weighted MRI scans and applied it to multicontrast EPImix scans, demonstrating the feasibility of deriving quantitative information from neuroimaging scans processed within minutes. Further research is needed to explore adaptive multimodal imaging and individualized neuroimaging examinations using this approach.
HUMAN BRAIN MAPPING
(2022)
Article
Anesthesiology
Daniel Martins, Ottavia Dipasquale, Mattia Veronese, Federico Turkheimer, Marco L. Loggia, Stephen McMahon, Matthew A. Howard, Steven C. R. Williams
Summary: This study examines alterations in morphometric similarity in chronic pain patients and identifies genetic and cellular correlates of these changes. The findings suggest that cortical remodeling in chronic pain may be influenced by multiple elements of the brain's cellular architecture and highlight potential pathways for future genetic association or drug development studies.
Article
Psychology, Clinical
Tanja Jaeckle, Steven C. R. Williams, Gareth J. Barker, Rodrigo Basilio, Ewan Carr, Kimberley Goldsmith, Alessandro Colasanti, Vincent Giampietro, Anthony Cleare, Allan H. Young, Jorge Moll, Roland Zahn
Summary: Self-guided psychological intervention with additional fMRI neurofeedback targeting self-blaming emotions showed potential in reducing symptoms in non-anxious MDD patients. However, further studies are needed to confirm these findings.
PSYCHOLOGICAL MEDICINE
(2023)
Editorial Material
Radiology, Nuclear Medicine & Medical Imaging
Giovanna Nordio, Gill Brown, Sagar Jilka, Alexander Hammers, Mitul A. Mehta, Anoushka Leslie, Steve Williams, Mattia Veronese
CLINICAL AND TRANSLATIONAL IMAGING
(2022)
Article
Industrial Relations & Labor
Saja Albelali, Steve Williams
Summary: This paper investigates the implications of the Nitaqat policy on gendered power relations in the workplace. The increased feminization of employment under Nitaqat has provided women workers with access to power resources and influenced the dynamics of gendered power relations in Saudi workplaces.
EMPLOYEE RELATIONS
(2022)
Article
Immunology
D. Martins, O. Dipasquale, K. Davies, E. Cooper, J. Tibble, M. Veronese, M. Frigo, S. C. R. Williams, F. Turkheimer, M. Cercignani, N. A. Harrison
Summary: Systemic inflammation induces acute changes in mood, motivation, and cognition that resemble depressive symptoms. This study investigated the effects of two treatments on brain function and identified potential pathways linking inflammation to psychopathology. The results showed that interferon-alpha and anti-TNF therapies both caused decreases in regional brain connectivity, but within different brain regions and through distinct transcriptomic vulnerability patterns. This finding suggests possible brain mechanisms through which changes in peripheral inflammation contribute to the development or resolution of psychopathology.
BRAIN BEHAVIOR AND IMMUNITY
(2022)
Article
Neurosciences
Marina Charquero-Ballester, Birgit Kleim, Diego Vidaurre, Christian Ruff, Eloise Stark, Jetro J. Tuulari, Hugh McManners, Yair Bar-Haim, Linda Bouquillon, Allison Moseley, Steven C. R. Williams, Mark W. Woolrich, Morten L. Kringelbach, Anke Ehlers
Summary: The study detected recurring large-scale brain functional states with high temporal precision in healthy trauma-exposed individuals and PTSD patients before and after successful CT-PTSD treatment. It was found that PTSD patients spent less time on specific default mode subnetworks after treatment, suggesting a rebalance in the dynamic aspect of brain function related to self-referential processes and threat detection.
HUMAN BRAIN MAPPING
(2022)
Article
Radiology, Nuclear Medicine & Medical Imaging
Emil Ljungberg, Tobias C. Wood, Ana Beatriz Solana, Steven C. R. Williams, Gareth J. Barker, Florian Wiesinger
Summary: This study developed a self-navigated motion correction method for 3D silent ZTE-based neuroimaging and characterized its performance for different types of head motion. The results showed that MERLIN achieved successful and consistent motion correction for various instructed motion paradigms.
MAGNETIC RESONANCE IN MEDICINE
(2022)
Review
Rheumatology
Jennifer G. Cox, Marius de Groot, James H. Cole, Steven C. R. Williams, Matthew J. Kempton
CLINICAL RHEUMATOLOGY
(2023)
Article
Neurosciences
Marie-Stephanie Cahart, Owen O'Daly, Vincent Giampietro, Maarten Timmers, Johannes Streffer, Steven Einstein, Fernando Zelaya, Flavio Dell'Acqua, Steven C. R. Williams
Summary: This study compared the reliability of conventional single-band fMRI and different multiband (MB) fMRI acquisitions with and without in-plane acceleration across multiple scanning sessions. It found that for cortical areas, MB factor 4 without in-plane acceleration had the highest reliability, while for subcortical areas, conventional single-band fMRI was more reliable.
HUMAN BRAIN MAPPING
(2023)
Editorial Material
Biochemistry & Molecular Biology
Caroline D. Rae, Stephen R. Williams
Summary: The ISMRM study group has made recommendations for reporting methods in magnetic resonance spectroscopy and the Journal of Neurochemistry has decided to promote the use of a checklist based on these standards. This aims to enhance reproducibility and reliability of scientific research, facilitate the work of reviewers, and contribute to the education of the scientific community.
JOURNAL OF NEUROCHEMISTRY
(2023)
Article
Multidisciplinary Sciences
Jenni Leppanen, Olivia Patsalos, Sophie Surguladze, Jess Kerr-Gaffney, Steven Williams, Ketevan Tchanturia
Summary: This study aimed to develop more ecologically valid measures of top-down interpretation biases and bottom-up evoked emotional responses. The results showed that participants were more attuned to the negative cues in the ambiguous film clips and their mood ratings and facial affect during the viewing of emotionally provoking film clips were as expected. However, some film clips were considered unsuitable for assessing interpretation bias.
Article
Neurosciences
Timothy Lawn, Daniel Martins, Owen O'Daly, Steve Williams, Matthew Howard, Ottavia Dipasquale
Summary: Placing a patient under anesthesia is crucial in surgical practice, but the mechanisms by which anesthetic drugs affect consciousness are poorly understood. Using REACT, a multi-modal imaging technique, this study investigated how different levels of propofol-induced sedation affect neurotransmission-related functional connectivity. The results showed that propofol increased GABA-A and noradrenaline transporter-enriched functional connectivity in occipital and somatosensory regions, respectively. During auditory stimulation, the dopaminergic network exhibited reduced functional connectivity, particularly in bilateral temporal and mid/posterior cingulate cortices, with an interaction between auditory stimulation and level of consciousness observed in the right temporal cluster. By integrating micro- and macro-scale systems, this study provides evidence for direct GABAergic and indirect noradrenergic and dopaminergic-related network changes under propofol sedation, highlighting the utility of REACT in exploring the molecular substrates of consciousness and cognition.
Article
Oncology
Steven C. R. Williams, Ndaba Mazibuko, Owen O'Daly, Christian Zurth, Fiona Patrick, Christian Kappeler, Iris Kuss, Patricia E. Cole
Summary: This study compared the effects of two androgen receptor inhibitors, darolutamide and enzalutamide, and placebo on blood flow in the brain. Enzalutamide reduced cerebral blood flow, while darolutamide did not significantly affect it.
Article
Management
Patricia Kinsella, Steve Williams, Peter Scott, Rita Fontinha
Summary: Despite growing interest in the influence of social and institutional settings on career trajectories, there is limited research on the comparative differences in boundaryless careers. Based on qualitative interviews with ICT professionals in the UK and Germany, the study finds that there is little evidence of active engagement with boundaryless careers among ICT professionals, despite working in a sector where it would be expected. The findings also highlight cross-national differences, with directly employed ICT professionals in Germany being more concerned about job insecurity compared to their UK counterparts.
INTERNATIONAL JOURNAL OF HUMAN RESOURCE MANAGEMENT
(2022)
