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A Comparative Study of the L2 Pragmatic Competence of University Students in Hong Kong and the Chinese Mainland:The Contributions of Sociocultural Context and Linguistic Proficiency
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作者 Scott AUBREY Rod ELLIS 《Chinese Journal of Applied Linguistics》 2024年第3期371-392,524,共23页
This study investigates the differences in pragmatic competence between Hong Kong and Chinese mainland university students.Participants included 19 native speakers of English,115 Chinese mainland students,divided into... This study investigates the differences in pragmatic competence between Hong Kong and Chinese mainland university students.Participants included 19 native speakers of English,115 Chinese mainland students,divided into those who had spent time abroad in an English-speaking country(CM A)and those who had not(CM NA),and 97 Hong Kong students,divided into those from an English-medium secondary school(Hong Kong EMI)and those from a Chinese-medium school(Hong Kong CMI).Linguistic proficiency was measured by a C-test,and pragmatic competence by a Metapragmatic Knowledge Test,an Irony Test and a Monologic Role Play.Group scores were compared using ANCOVAs to control for differences in proficiency.The results point to a continuum of pragmatic competence—EMI>CMI>CM A>CM NA—reflecting the groups’access to English in real-life contexts.The differences between the Hong Kong groups and the Chinese mainland groups were clearest in those tests measuring processing capacity(i.e.,Irony Response Time and the Monologic Role Play).CM A,but not CM NA,performed as well as the Hong Kong groups on measures of metapragmatic awareness.The results are discussed in terms of Bialystok’s(1993)distinction between analyzed representation and control of processing. 展开更多
关键词 pragmatic competence social context Hong Kong the Chinese mainland metapragmatic knowledge processing capacity
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哀牢山构造带新元古代双峰式岩浆岩的锆石U-Pb年代学、元素-同位素地球化学特征及构造意义
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作者 苏路路 魏月华 +3 位作者 杨朝 刘桂春 刘嵘 訾建威 《大地构造与成矿学》 EI CAS CSCD 北大核心 2024年第5期1148-1166,共19页
分布于扬子克拉通西缘的新元古代岩浆岩对研究华南陆块的前寒武纪演化及其与Rodinia超大陆的关系意义重大,但由于该区域后期构造-热历史的复杂性,关于一些重要岩石单元的时代、属性和构造背景仍存在诸多争议。本文聚焦哀牢山构造带南段... 分布于扬子克拉通西缘的新元古代岩浆岩对研究华南陆块的前寒武纪演化及其与Rodinia超大陆的关系意义重大,但由于该区域后期构造-热历史的复杂性,关于一些重要岩石单元的时代、属性和构造背景仍存在诸多争议。本文聚焦哀牢山构造带南段的桃家寨岩体,报道了来自该岩体的一套变基性岩和钠长花岗岩组合的年代学和地球化学组成,以期为解决现存争议提供新的证据和约束。SHRIMP原位锆石U-Pb同位素测年表明变基性岩和钠长花岗岩的结晶年龄分别为756±9 Ma和763±23 Ma,表明二者为同期岩浆作用的产物,其合并加权平均年龄759±7 Ma(MSWD=0.88,n=8)代表了岩浆事件年龄;同时,来自两件样品的锆石都记录了~730 Ma的岩浆后热扰动事件。变基性岩具有低碱(Na2O+K2O=0.17%~0.36%),高Mg#(76~79)的地球化学特征,略富集轻稀土元素(LREEs),并具有弱的Nb-Ta负异常和正的ε_(Nd)(t)值(+2.67~+3.10),表明其来自E-MORB型富集地幔岩浆源区,可能经历了俯冲板片流体或者熔体的改造。钠长花岗岩显示高碱(Na_(2)O+K_(2)O=6.70%~8.30%)、富集LREEs和大离子亲石元素(LILEs)、亏损重稀土元素(HREEs)等特点,具有负的ε_(Nd)(t)值(-2.43~-1.26),表明其母岩浆可能源自下地壳物质部分熔融与基性熔体的混合。综合前人研究,发现桃家寨岩体的岩石组合具有双峰式特点,并在地球化学特征上显示典型的弧-弧后盆地属性;岩浆作用峰期~760 Ma,指示其为新元古代扬子克拉通西缘的洋陆俯冲构造体系的一部分,从而为将华南陆块置于Rodinia外围的超大陆重建模式提供了新的证据。 展开更多
关键词 哀牢山构造带 桃家寨岩体 新元古代 双峰式岩浆岩 SHRIMP锆石U-PB年代学 地球化学
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Enhanced High-Temperature Cycling Stability of Garnet-Based All Solid-State Lithium Battery Using a Multi-Functional Catholyte Buffer Layer
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作者 Leqi Zhao Yijun Zhong +2 位作者 Chencheng Cao Tony Tang Zongping Shao 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第7期59-73,共15页
The pursuit of safer and high-performance lithium-ion batteries(LIBs)has triggered extensive research activities on solid-state batteries,while challenges related to the unstable electrode-electrolyte interface hinder... The pursuit of safer and high-performance lithium-ion batteries(LIBs)has triggered extensive research activities on solid-state batteries,while challenges related to the unstable electrode-electrolyte interface hinder their practical implementation.Polymer has been used extensively to improve the cathode-electrolyte interface in garnet-based all-solid-state LIBs(ASSLBs),while it introduces new concerns about thermal stability.In this study,we propose the incorporation of a multi-functional flame-retardant triphenyl phos-phate additive into poly(ethylene oxide),acting as a thin buffer layer between LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)cathode and garnet electro-lyte.Through electrochemical stability tests,cycling performance evaluations,interfacial thermal stability analysis and flammability tests,improved thermal stability(capacity retention of 98.5%after 100 cycles at 60℃,and 89.6%after 50 cycles at 80℃)and safety characteristics(safe and stable cycling up to 100℃)are demonstrated.Based on various materials characterizations,the mechanism for the improved thermal stability of the interface is proposed.The results highlight the potential of multi-functional flame-retardant additives to address the challenges associated with the electrode-electrolyte interface in ASSLBs at high temperature.Efficient thermal modification in ASSLBs operating at elevated temperatures is also essential for enabling large-scale energy storage with safety being the primary concern. 展开更多
关键词 Solid-state battery Cathode electrolyte interlayer Flame-retardant additive Cycling stability Interfacial stability
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Cardiovascular computed tomography in cardiovascular disease:An overview of its applications from diagnosis to prediction
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作者 Zhong-Hua SUN 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2024年第5期550-576,共27页
Cardiovascular computed tomography angiography(CTA)is a widely used imaging modality in the diagnosis of cardiovascular disease.Advancements in CT imaging technology have further advanced its applications from high di... Cardiovascular computed tomography angiography(CTA)is a widely used imaging modality in the diagnosis of cardiovascular disease.Advancements in CT imaging technology have further advanced its applications from high diagnostic value to minimising radiation exposure to patients.In addition to the standard application of assessing vascular lumen changes,CTA-derived applications including 3D printed personalised models,3D visualisations such as virtual endoscopy,virtual reality,augmented reality and mixed reality,as well as CT-derived hemodynamic flow analysis and fractional flow reserve(FFRCT)greatly enhance the diagnostic performance of CTA in cardiovascular disease.The widespread application of artificial intelligence in medicine also significantly contributes to the clinical value of CTA in cardiovascular disease.Clinical value of CTA has extended from the initial diagnosis to identification of vulnerable lesions,and prediction of disease extent,hence improving patient care and management.In this review article,as an active researcher in cardiovascular imaging for more than 20 years,I will provide an overview of cardiovascular CTA in cardiovascular disease.It is expected that this review will provide readers with an update of CTA applications,from the initial lumen assessment to recent developments utilising latest novel imaging and visualisation technologies.It will serve as a useful resource for researchers and clinicians to judiciously use the cardiovascular CT in clinical practice. 展开更多
关键词 DIAGNOSIS CARDIOVASCULAR PREDICTION
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改善不同地应力下隧道轮廓爆破成型效果
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作者 周子龙 王培宇 +2 位作者 程瑞山 陈翠刚 蔡鑫 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第3期930-949,共20页
含预切空腔的轮廓爆破技术被认为是改善高地应力下隧道轮廓成型的有效方法。然而,对这种爆破技术在不同地应力下性能的研究较少。本文通过校验后的公路隧道数值模型,调查了含预切空腔(PC)的两种典型轮廓爆破技术(即光面爆破(SB)和预裂爆... 含预切空腔的轮廓爆破技术被认为是改善高地应力下隧道轮廓成型的有效方法。然而,对这种爆破技术在不同地应力下性能的研究较少。本文通过校验后的公路隧道数值模型,调查了含预切空腔(PC)的两种典型轮廓爆破技术(即光面爆破(SB)和预裂爆破(PB))在不同地应力条件下的性能。结果表明,在耦合装药和50 MP地应力下,PCSB比PCPB能获得更好的隧道轮廓成型效果。此外,研究了两种轮廓爆破技术在不同的不耦合系数和地应力条件下的性能,发现随着地应力从30 MPa增加至50 MPa,PCSB和PCPB作用下隧道轮廓成型效果均逐渐改善。此外,在不同地应力条件下调整周边孔的不耦合系数能使PCPB形成有效的隧道轮廓。然而,对于PCSB,在不同地应力条件下,需调整所有炮孔的不耦合系数才能形成符合要求的隧道轮廓。最后通过多元非线性回归获得经验公式,本研究可以为不同地应力下使用PCSB和PCPB开挖隧道提供设计参考。 展开更多
关键词 地应力 光面爆破 预裂爆破 隧道轮廓成型 不耦合系数
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Mechanical behaviour of fiber-reinforced grout in rock bolt reinforcement
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作者 Yingchun Li Ammar Ahmed Danqi Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期437-453,共17页
Grouted rock bolts subject to axial loading in the field exhibit various failure modes,among which the most predominant one is the bolt-grout interface failure.Thus,mechanical characterization of the grout is essentia... Grouted rock bolts subject to axial loading in the field exhibit various failure modes,among which the most predominant one is the bolt-grout interface failure.Thus,mechanical characterization of the grout is essential for understanding its performance in ground support.To date,few studies have been conducted to characterize the mechanical behaviour of fiber-reinforced grout(FRG)in rock bolt reinforcement.Here we experimentally studied the mechanical behaviour of FRG under uniaxial compression,indirect tension,and direct shear loading conditions.We also conducted a series of pullout tests of rebar bolt encapsulated with different grouts including conventional cementitious grout and FRG.FRG was developed using 15%silica fume(SF)replacement of cement(by weight)and steel fiber to achieve highstrength and crack-resistance to overcome drawbacks of the conventional grout.Two types of steel fibers including straight and wavy steel fibers were further added to enhance the grout quality.The effect of fiber shape and fiber volume proportion on the grout mechanical properties were examined.Our experimental results showed that the addition of SF and steel fiber by 1.5%fiber volume proportion could lead to the highest compressive,tensile,and shear strengths of the grout.The minimum volume of fiber that could improve the mechanical properties of grout was found at 0.5%.The scanning electron microscopy(SEM)analysis demonstrated that steel fibers act as an excellent bridge to prevent the cracks from propagating at the interfacial region and hence to aid in maintaining the integrity of the cementitious grout.Our laboratory pullout tests further confirmed that FRG could prevent the cylindrical grout annulus from radial crack and hence improve the rebar’s load carrying capacity.Therefore,FRG has a potential to be utilized in civil and mining applications where high-strength and crack-resistance support is required. 展开更多
关键词 Fiber-reinforced grout(FRG) Steel fibers Mechanical properties Direct shear test Pullout test
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Community-led total sanitation(CLTS)implementation in West Mamprusi Municipal Assembly in Ghana.What do communities think eleven years on?
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作者 Elijah Adam Emmanuel Badu 《Global Health Journal》 2024年第2期67-73,共7页
Objective Access to improved sanitation is a fundamental human right and an important aspect of Public Health.However,an estimated thousands of people in Ghana especially,the West Mamprusi Municipal Assembly(WMMA)stil... Objective Access to improved sanitation is a fundamental human right and an important aspect of Public Health.However,an estimated thousands of people in Ghana especially,the West Mamprusi Municipal Assembly(WMMA)still have no access to adequate toilet facilities.This has brought untold health repercussions to the inhabitants,the community,and the environment at large.To address this menace,the community-led total sanitation(CLTS)was implemented.This study aimed to assess communities’perspectives on the implementation of CLTS and to understand the factors influencing its success and failures.Methods A mixed-method approach involving sequential qualitative and quantitative methods was employed in this study.Participants for the quantitative study were randomly selected and surveyed using questionnaires.The qualitative study employed focus group discussion involving purposively sampled participants including assembly members,opinion leaders,and assembly staff.Results The CLTS program in WMMA realized an apparent use of construction and proper use of household latrines leading to a reduction of open defecation free(ODF)and two communities achieving sanitized status in the history of the study area,enabling the training of latrine artisans and natural leaders to facilitate the CLTS expansion and sustainability,improved sanitation and hygiene,strengthened the enforcement of community rules and regulations and many others.Conclusion The CLTS program has received more widespread acceptance in the study area than the previous government policy of constructing public toilets,which was greeted with massive failures due to poor implementation.To ensure that gains achieved through CLTS implementation are sustained longer,it is recommended that chiefs and opinion leaders should be involved in the CLTS programs to ensure checks and enforcement.The entrenchment of bylaws and more education to address enduring myths and misconceptions will sustain the program.Subsidies in the form of sanitation loans for latrine construction materials by the government and supporting non-governmental organizations(NGOs)will be paramount in sustaining ODF. 展开更多
关键词 Community-led total sanitation(CLTS) Community development Ghana SANITATION
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Performance of water-coupled charge blasting under different in-situ stresses
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作者 ZHOU Zi-long WANG Zhen +2 位作者 CHENG Rui-shan CAI Xin LAN Ri-yan 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2300-2320,共21页
Water-coupled charge blasting is a promising technique to efficiently break rock masses.In this study,numerical models of double boreholes with water-coupled charge are established using LS-DYNA and are calibrated by ... Water-coupled charge blasting is a promising technique to efficiently break rock masses.In this study,numerical models of double boreholes with water-coupled charge are established using LS-DYNA and are calibrated by the tests of rock masses subjected to explosion loads to examine its performance.The crack levels of rock mass induced by water-coupled charge blasting and air-coupled charge blasting are first compared.It is found that water-coupled charge blasting is more appropriate to fracture deep rock mass than air-coupled charge blasting.In addition,the effects of rock properties,water-coupled charge coefficients,and borehole connection angles on the performance of water-coupled charge blasting are investigated.The results show that rock properties and water-coupled charge coefficients can greatly influence the crack and fragmentation levels of rock mass induced by water-coupled charge blasting under uniform and non-uniform in-situ stresses.However,changing borehole-connection angles can only affect crack and fragmentation levels of rock mass under non-uniform in-situ stresses but barely affect those under uniform in-situ stresses.A formula is finally proposed by considering the above-mentioned factors to provide the design suggestion of water-coupled charge blasting to fracture rock mass with different in-situ stresses. 展开更多
关键词 water-coupled blasting in-situ stress water-coupled charge coefficient rock type borehole-connection angle
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Hydrogen Storage Performance During Underground Hydrogen Storage in Depleted Gas Reservoirs:A Review
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作者 Lingping Zeng Regina Sander +1 位作者 Yongqiang Chen Quan Xie 《Engineering》 SCIE EI CAS CSCD 2024年第9期211-225,共15页
Hydrogen has emerged as a promising alternative to meet the growing demand for sustainable and renewable energy sources.Underground hydrogen storage(UHS)in depleted gas reservoirs holds significant potential for large... Hydrogen has emerged as a promising alternative to meet the growing demand for sustainable and renewable energy sources.Underground hydrogen storage(UHS)in depleted gas reservoirs holds significant potential for large-scale energy storage and the seamless integration of intermittent renewable energy sources,due to its capacity to address challenges associated with the intermittent nature of renewable energy sources,ensuring a steady and reliable energy supply.Leveraging the existing infrastructure and well-characterized geological formations,depleted gas reservoirs offer an attractive option for large-scale hydrogen storage implementation.However,significant knowledge gaps regarding storage performance hinder the commercialization of UHS operation.Hydrogen deliverability,hydrogen trapping,and the equation of state are key areas with limited understanding.This literature review critically analyzes and synthesizes existing research on hydrogen storage performance during underground storage in depleted gas reservoirs;it then provides a high-level risk assessment and an overview of the techno-economics of UHS.The significance of this review lies in its consolidation of current knowledge,highlighting unresolved issues and proposing areas for future research.Addressing these gaps will advance hydrogen-based energy systems and support the transition to a sustainable energy landscape.Facilitating efficient and safe deployment of UHS in depleted gas reservoirs will assist in unlocking hydrogen’s full potential as a clean and renewable energy carrier.In addition,this review aids policymakers and the scientific community in making informed decisions regarding hydrogen storage technologies. 展开更多
关键词 Underground hydrogen storage Storage performance Hydrogen deliverability Hydrogen trapping Risk assessment Techno-economic analysis
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Investigation and optimization of high-valent Ta-doped SrFeO_(3-δ)as air electrode for intermediate-temperature solid oxide fuel cells
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作者 Shanshan Jiang Hao Qiu +7 位作者 Shaohua Xu Xiaomin Xu Jingjing Jiang Beibei Xiao Paulo Sérgio Barros Juliao) Chao Su Daifen Chen Wei Zhou 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第9期2102-2109,共8页
To explore highly active and thermomechanical stable air electrodes for intermediate-temperature solid oxide fuel cells(ITSOFCs),10mol%Ta5+doped in the B site of strontium ferrite perovskite oxide(SrTa_(0.1)Fe_(0.9)O_... To explore highly active and thermomechanical stable air electrodes for intermediate-temperature solid oxide fuel cells(ITSOFCs),10mol%Ta5+doped in the B site of strontium ferrite perovskite oxide(SrTa_(0.1)Fe_(0.9)O_(3-δ),STF)is investigated and optimized.The effects of Ta^(5+)doping on structure,transition metal reduction,oxygen nonstoichiometry,thermal expansion,and electrical performance are evaluated systematically.Via 10mol%Ta^(5+)doping,the thermal expansion coefficient(TEC)decreased from 34.1×10^(-6)(SrFeO_(3-δ))to 14.6×10^(-6) K^(-1)(STF),which is near the TEC of electrolyte(13.3×10^(-6) K^(-1) for Sm_(0.2)Ce_(0.8)O_(1.9),SDC),indicates excellent thermomechanical compatibility.At 550-750℃,STF shows superior oxygen vacancy concentrations(0.262 to 0.331),which is critical in the oxygen-reduction reaction(ORR).Oxygen temperature-programmed desorption(O_(2)-TPD)indicated the thermal reduction onset temperature of iron ion is around 420℃,which matched well with the inflection points on the thermos-gravimetric analysis and electrical conductivity curves.At 600℃,the STF electrode shows area-specific resistance(ASR)of 0.152Ω·cm^(2) and peak power density(PPD)of 749 mW·cm^(-2).ORR activity of STF was further improved by introducing 30wt%Sm_(0.2)Ce_(0.8)O_(1.9)(SDC)powder,STF+SDC composite cathode achieving outstanding ASR value of 0.115Ω·cm2 at 600℃,even comparable with benchmark cobalt-containing cathode,Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-δ)(BSCF).Distribution of relaxation time(DRT)analysis revealed that the oxygen surface exchange and bulk diffusion were improved by forming a composite cathode.At 650℃,STF+SDC composite cathode achieving an outstanding PPD of 1117 mW·cm^(-2).The excellent results suggest that STF and STF+SDC are promising air electrodes for IT-SOFCs. 展开更多
关键词 strontium ferrite-based perovskite Ta doping composite cathode intermediate-temperature solid oxide fuel cells
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Source Enrichment Control on the Scale of Magmatic-Hydrothermal W-Sn Mineralization:Insights from Triassic and Jurassic Magma Reservoirs in the Continental Crust,Xitian,South China
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作者 GUO Chunli Simon AWILDE +2 位作者 Coralie SIEGEL CHEN Zhenyu WU Shichong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期132-149,共18页
There are two factors,source composition and magmatic differentiation,potentially controlling W-Sn mineralization.Which one is more important is widely debated and may need to be determined for each individual deposit... There are two factors,source composition and magmatic differentiation,potentially controlling W-Sn mineralization.Which one is more important is widely debated and may need to be determined for each individual deposit.The Xitian granite batholith located in South China is a natural laboratory for investigating the above problem.It consists essentially of two separate components,formed in the Triassic at ca.226 Ma and Jurassic at ca.152 Ma,respectively.The Triassic and Jurassic rocks are both composed of porphyritic and fine-grained phases.The latter resulted from highlydifferentiated porphyritic ones but they have similar textural characteristics and mineral assemblages,indicating that they reached a similar degree of crystal fractionation.Although both fine-grained phases are highly differentiated with elevated rare metal contents,economic W–Sn mineralization is rare in the Triassic granitoids and this can be attributed to less fertile source materials than their Jurassic counterparts,with a slightly more enriched isotopic signature and whole-rockεNd(226 Ma)of−10.4 to−9.2(2σ=0.2)compared withεNd(152 Ma)of−9.2 to−8.2(2σ=0.2)for the Jurassic rocks.The initial W-Sn enrichment was derived from the metasedimentary rocks and strongly enhanced by reworking of the continental crust,culminating in the Jurassic. 展开更多
关键词 W-Sn mineralization magma reservoir geometry crystal fractionation Xitian Triassic-Jurassic granitic batholith Nanling Range South China
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Tuning synergy between nickel and iron in Ruddlesden-Popper perovskites through controllable crystal dimensionalities towards enhanced oxygenevolving activity and stability
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作者 Haijuan Zhang Daqin Guan +4 位作者 Yuxing Gu Hengyue Xu Chunchang Wang Zongping Shao Youmin Guo 《Carbon Energy》 SCIE EI CAS CSCD 2024年第6期113-123,共11页
Ni-Fe-based oxides are among the most promising catalysts developed to date for the bottleneck oxygen evolution reaction(OER)in water electrolysis.However,understanding and mastering the synergy of Ni and Fe remain ch... Ni-Fe-based oxides are among the most promising catalysts developed to date for the bottleneck oxygen evolution reaction(OER)in water electrolysis.However,understanding and mastering the synergy of Ni and Fe remain challenging.Herein,we report that the synergy between Ni and Fe can be tailored by crystal dimensionality of Ni,Fe-contained Ruddlesden-Popper(RP)-type perovskites(La_(0.125)Sr_(0.875))n+1(Ni_(0.25)Fe_(0.75))nO3n+1(n=1,2,3),where the material with n=3 shows the best OER performance in alkaline media.Soft X-ray absorption spectroscopy spectra before and after OER reveal that the material with n=3 shows enhanced Ni/Fe-O covalency to boost the electron transfer as compared to those with n=1 and n=2.Further experimental investigations demonstrate that the Fe ion is the active site and the Ni ion is the stable site in this system,where such unique synergy reaches the optimum at n=3.Besides,as n increases,the proportion of unstable rock-salt layers accordingly decreases and the leaching of ions(especially Sr^(2+))into the electrolyte is suppressed,which induces a decrease in the leaching of active Fe ions,ultimately leading to enhanced stability.This work provides a new avenue for rational catalyst design through the dimensional strategy. 展开更多
关键词 crystal dimensionalities oxygen evolution reaction Ruddlesden-Popper perovskites SYNERGY
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Impact of climate change and human activities on the spatiotemporal dynamics of surface water area in Gansu Province, China
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作者 LU Haitian ZHAO Ruifeng +3 位作者 ZHAO Liu LIU Jiaxin LYU Binyang YANG Xinyue 《Journal of Arid Land》 SCIE CSCD 2024年第6期798-815,共18页
Understanding the dynamics of surface water area and their drivers is crucial for human survival and ecosystem stability in inland arid and semi-arid areas.This study took Gansu Province,China,a typical area with comp... Understanding the dynamics of surface water area and their drivers is crucial for human survival and ecosystem stability in inland arid and semi-arid areas.This study took Gansu Province,China,a typical area with complex terrain and variable climate,as the research subject.Based on Google Earth Engine,we used Landsat data and the Open-surface Water Detection Method with Enhanced Impurity Control method to monitor the spatiotemporal dynamics of surface water area in Gansu Province from 1985 to 2022,and quantitatively analyzed the main causes of regional differences in surface water area.The findings revealed that surface water area in Gansu Province expanded by 406.88 km2 from 1985 to 2022.Seasonal surface water area exhibited significant fluctuations,while permanent surface water area showed a steady increase.Notably,terrestrial water storage exhibited a trend of first decreasing and then increasing,correlated with the dynamics of surface water area.Climate change and human activities jointly affected surface hydrological processes,with the impact of climate change being slightly higher than that of human activities.Spatially,climate change affected the'source'of surface water to a greater extent,while human activities tended to affect the'destination'of surface water.Challenges of surface water resources faced by inland arid and semi-arid areas like Gansu Province are multifaceted.Therefore,we summarized the surface hydrology patterns typical in inland arid and semi-arid areas and tailored surface water'supply-demand'balance strategies.The study not only sheds light on the dynamics of surface water area in Gansu Province,but also offers valuable insights for ecological protection and surface water resource management in inland arid and semi-arid areas facing water scarcity. 展开更多
关键词 surface water area terrestrial water storage Open-surface Water Detection Method with Enhanced Impurity Control method Google Earth Engine climate change human activities inland arid and semi-arid areas
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A randomized controlled trial of Promoting Physical Activity in Regional and Remote Cancer Survivors(PPARCS)
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作者 Sarah J.Hardcastle Chloe Maxwell-Smith +12 位作者 Vinicius Cavalheri Terry Boyle Marta Leyton Román Cameron Platell Michael Levitt Christobel Saunders Frank Sardelic Sophie Nightingale Jacob McCormick Craig Lynch Paul A.Cohen Max Bulsara Dana Hince 《Journal of Sport and Health Science》 SCIE CSCD 2024年第1期81-89,共9页
Background:Physical activity(PA)is important for cancer survivors.Trials of remotely delivered interventions are needed to assist in reaching under-served non-metropolitan cancer survivors.The objective of this study ... Background:Physical activity(PA)is important for cancer survivors.Trials of remotely delivered interventions are needed to assist in reaching under-served non-metropolitan cancer survivors.The objective of this study was to ascertain whether wearable technology,coupled with health coaching was effective in increasing PA in breast and colorectal cancer survivors living in regional and remote areas in Australia.Methods:Cancer survivors from 5 states were randomized to intervention and control arms.Intervention participants were given a Fitbit Charge 2TMand received up to 6 telephone health coaching sessions.Control participants received PA print materials.Accelerometer assessments at baseline and 12 weeks measured moderate-to-vigorous PA(MVPA),light PA,and sedentary behavior.Results:Eighty-seven participants were recruited(age=63±11 years;74(85%)female).There was a significant net improvement in MVPA of 49.8 min/week,favoring the intervention group(95%confidence interval(95%CI):13.6-86.1,p=0.007).There was also a net increase in MVPA bouts of 39.5 min/week(95%CI:11.9-67.1,p=0.005),favoring the intervention group.Both groups improved light PA and sedentary behavior,but there were no between-group differences.Conclusion:This’s the first study to demonstrate that,when compared to standard practice(i.e.,PA education),a wearable technology intervention coupled with distance-based health coaching,improves MVPA in non-metropolitan cancer survivors.The results display promise for the use of scalable interventions using smart wearable technology in conjunction with phone-based health coaching to foster increased PA in geographically disadvantaged cancer survivors. 展开更多
关键词 Behavior change EXERCISE Health disparities ONCOLOGY Wearable technology
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Electricity Generation from Heatwaves
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作者 Diandong Ren Mervyn J. Lynch 《International Journal of Geosciences》 CAS 2024年第5期449-457,共9页
We chose a definition of heatwaves (HWs) that has ~4-year recurrence frequency at world hot spots. We first examined the 1940-2022 HWs climatology and trends in lifespan, severity, spatial extent, and recurrence frequ... We chose a definition of heatwaves (HWs) that has ~4-year recurrence frequency at world hot spots. We first examined the 1940-2022 HWs climatology and trends in lifespan, severity, spatial extent, and recurrence frequency. HWs are becoming more frequent and more severe for extratropical mid- and low-latitudes. To euphemize HWs, we here propose a novel clean energy-tapping concept that utilizes the available nano-technology, micro-meteorology knowledge of temperature distribution within/without buildings, and radiative properties of earth atmosphere. The key points for a practical electricity generation scheme from HWs are defogging, insulation, and minimizing the absorption of infrared downward radiation at the cold legs of the thermoelectric generators. One sample realization is presented which, through relay with existing photovoltaic devices, provides all-day electricity supply sufficient for providing air conditioning requirement for a residence (~2000-watt throughput). The provision of power to air conditioning systems, usually imposes a significant stress on traditional city power grids during heatwaves. 展开更多
关键词 Heatwaves Climate Warming Clean Energy Generation by Thermoelectric Generator Ameliorate and Transcend Heatwaves Climate Warming Mitigation and Adaptation Thermoelectric Generator (TEG) IR Interaction with Periodically Arranged Nanostructures Optical Properties of Nano Fabricating Passive Clean Energy Tapping/Generation
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Comparative impact behaviours of ultra high performance concrete columns reinforced with polypropylene vs steel fibres
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作者 Thong M.Pham Harrison Hyde +4 位作者 Maw K.Kaung Yan Zhuge Duong T.Tran Des Vlietstra Tung M.Tran 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第10期138-153,共16页
Polypropylene(PP)fibres have primarily used to control shrinkage cracks or mitigate explosive spalling in concrete structures exposed to fire or subjected to impact/blast loads,with limited investigations on capacity ... Polypropylene(PP)fibres have primarily used to control shrinkage cracks or mitigate explosive spalling in concrete structures exposed to fire or subjected to impact/blast loads,with limited investigations on capacity improvement.This study unveils the possibility of using PP micro-fibres to improve the impact behaviour of fibre-reinforced ultra-high-performance concrete(FRUHPC)columns.Results show that the addition of fibres significantly improves the impact behaviour of FRUHPC columns by shifting the failure mechanism from brittle shear to favourable flexural failure.The addition of steel or PP fibres affected the impact responses differently.Steel fibres considerably increased the peak impact force(up to 18%)while PP micro-fibres slightly increased the peak(3%-4%).FRUHPC significantly reduced the maximum midheight displacement by up to 30%(under 20impact)and substantially improved the displacement recovery by up to 100%(under 20impact).FRUHPC with steel fibres significantly improved the energy absorption while those with PP micro-fibres reduced the energy absorption,which is different from the effect of PP-macro fibre reported in the literature.The optimal fibre content for micro-PP fibres is 1%due to its minimal fibre usage and low peak and residual displacement.This study highlights the potential of FRUHPC as a promising material for impact-resistant structures by creating a more favourable flexural failure mechanism,enhancing ductility and toughness under impact loading,and advancing the understanding of the role of fibres in structural performance. 展开更多
关键词 Ultra high-performance concrete Steel fibre Polypropylene micro-fibre Fibre volume fraction Impact loading Pendulum tests COLUMNS
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Modification,application and expansion of electrode materials based on cobalt telluride
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作者 Huilin Fan Yao Dai +7 位作者 Xiaoyun Xue Runguo Zheng Yuan Wang Hamidreza Arandiyan Zhiyuan Wang Zongping Shao Hongyu Sun Yanguo Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期710-737,I0015,共29页
Metal(Li,Na,K,Al)-ion batteries and lithium-sulfur and lithium-tellurium batteries are gaining recognition for their eco-friendly characteristics,substantial energy density,and sustainable attributes.However,the overa... Metal(Li,Na,K,Al)-ion batteries and lithium-sulfur and lithium-tellurium batteries are gaining recognition for their eco-friendly characteristics,substantial energy density,and sustainable attributes.However,the overall performance of rechargeable batteries heavily depends on their electrode materials.Transition metal tellurides have recently gained significant attention due to their high electrical conductivity and density.Cobalt telluride has received the most extensive research due to its catalytic activity,unique magnetic properties,and diverse composition and crystal structure.Nevertheless,its limited conductivity and significant volume variation contribute to electrode structural deterioration and rapid capacity decline.This review comprehensively summarizes recent advances in rational design and synthesis of modified cobalt telluride-based electrodes,encompassing defect engineering(Te vacancies,cation vacancies,heterointerfaces,and homogeneous interfaces)and composite engineering(derived carbon from precursors,carbon fibers,Mxene,graphene nanosheets,etc.).Particularly,the intricate evolution mechanisms of the conversion reaction process during cycling are elucidated.Furthermore,these modified strategies applied to other transitional metal tellurides,such as iron telluride,nickel telluride,zinc telluride,copper telluride,molybdenum telluride,etc.,are also thoroughly summarized.Additionally,their application extends to emerging aqueous zinc-ion batteries.Finally,potential challenges and prospects are discussed to further propel the development of transition metal tellurides electrode materials for next-generation rechargeable batteries. 展开更多
关键词 Rechargeable batteries Transition metal tellurides Cobalt telluride Defect engineering Composite engineering
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Recent progress in two-dimensional metallenes and their potential application as electrocatalyst
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作者 Umer Shahzad Mohsin Saeed +7 位作者 Muhammad Fazle Rabbee Hadi M.Marwani Jehan Y.Al-Humaidi Muhammad Altaf Raed H.Althomali Kwang-Hyun Baek Md.Rabiul Awual Mohammed M.Rahman 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期577-598,共22页
In this article,we looked at metallenes,a novel class of two-dimensional(2D)metals that are attracting interest in the energy and catalysis sectors.Catalysis is one area where their exceptional physicochemical and ele... In this article,we looked at metallenes,a novel class of two-dimensional(2D)metals that are attracting interest in the energy and catalysis sectors.Catalysis is one area where their exceptional physicochemical and electrical characteristics might be useful.Metallenes are unique because they include several metal atoms that are not in a coordinated bond.This makes them more active and improves their atomic uti-lization,which in turn increases their catalytic potential.This article delves into the potential of two-dimensional metals as electrocatalysts for carbon dioxide reduction,fuel oxidation,oxygen evolution,and oxygen reduction reactions in the context of sustainable energy conversion.Owing to the exception-ally high surface-to-volume ratio,large surface area as well as their optimized atomic use efficiency,2D materials defined by atomic layers are crucial for surface-related sustainable energy applications.Due to its exceptional properties,such as high conductivity and the ability to enhance the exposure of active metal sites,2D metallenes have recently attracted a lot of interest for use in catalysis,electronics,and energy-related applications.With their highly mobility,adjustable surface states,and electrical struc-tures that can be fine-tuned,2D metallenes are promising nanostructure materials for use in energy con-version with the sustainable applications. 展开更多
关键词 Metallenes ELECTROCATALYSTS Electrochemical processes Atomically thin structure
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Chinese version of the Perth Alexithymia Questionnaire:psychometric properties and clinical applications
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作者 Xin-Lu Cai Qingying Ye +7 位作者 Ke Ni Lin Zhu Qian Zhang Minmin Yin Zhe Zhang Wei Wei David A.Preece Bao-Ming Li 《General Psychiatry》 CSCD 2024年第2期274-283,共10页
Background The alexithymia trait is of high clinical interest.The Perth Alexithymia Questionnaire(PAQ)was recently developed to enable detailed facet-level and valence-specific assessments of alexithymia.Aims In this ... Background The alexithymia trait is of high clinical interest.The Perth Alexithymia Questionnaire(PAQ)was recently developed to enable detailed facet-level and valence-specific assessments of alexithymia.Aims In this paper,we introduce the first Chinese version of the PAQ and examine its psychometric properties and clinical applications.Methods In Study 1,the PAQ was administered to 990 Chinese participants.We examined its factor structure,internal consistency,test-retest reliability,as well as convergent,concurrent and discriminant validity.In Study 2,four groups,including a major depressive disorder(MDD)group(n=50),a matched healthy control group for MDD(n=50),a subclinical depression group(n=50)and a matched healthy control group for subclinical depression(n=50),were recruited.Group comparisons were conducted to assess the clinical relevance of the PAQ.Results In Study 1,the intended five-factor structure of the PAQ was found to fit the data well.The PAQ showed good internal consistency and test-retest reliability,as well as good convergent,concurrent and discriminant validity.In Study 2,the PAQ was able to successfully distinguish the MDD group and the subclinical depression group from their matched healthy controls.Conclusions The Chinese version of the PAQ is a valid and reliable instrument for comprehensively assessing alexithymia in the general population and adults with clinical/subclinical depression. 展开更多
关键词 CLINICAL instrument matched
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Etiology of Pancytopenia in Tabriz Shahid Ghazi Hospital:A Cross-sectional Study in Iran
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作者 Hossein Azari Bostanabad Safa Mousavi +3 位作者 Mohammad Hossein Hosseini Sadra Sarandili Ali Esfahani Babak Nejati 《Proceedings of Anticancer Research》 2024年第4期104-115,共12页
Objective:Pancytopenia is characterized by a reduction in all three types of blood cells:erythrocytes,leukocytes,and platelets.Pancytopenia is caused by a wide range of diseases,leading to diagnostic conundrums.These ... Objective:Pancytopenia is characterized by a reduction in all three types of blood cells:erythrocytes,leukocytes,and platelets.Pancytopenia is caused by a wide range of diseases,leading to diagnostic conundrums.These causes can range from drug reactions to life-threatening diseases such as aplastic anemia and leukemia.This study aims to investigate the causes of pancytopenia,specifically focusing on age and gender differences among patients.Methods:This cross-sectional study includes patients of all ages diagnosed with pancytopenia,as indicated by a CBC/H1 showing a WBC count less than 4,000/μL,platelet count less than 150,000/μL,and hemoglobin levels below 12 g/dL in women and less than 13 g/dL in men.The study only included patients with pancytopenia who underwent bone marrow examination and were not subjected to chemotherapy or radiation therapy.Results:A total of 133 patients with pancytopenia were included in the study.The average age was 47.35±17.62 years old,with 66%of the participants being male and 34%being female.Acute leukemia,specifically acute myeloid leukemia(AML)and acute lymphoid leukemia(ALL),was identified as the primary cause of pancytopenia,accounting for 31.5%of cases.Megaloblastic anemia was the second most common cause,accounting for 30%of cases,followed by aplastic anemia at 7.5%.Conclusion:Pancytopenia,a condition marked by the decrease in both erythrocytes and leukocytes as well as thrombocytes,can arise from a myriad of causes.The main findings of this study revealed that megaloblastic anemia,acute myeloid leukemia(AML),and acute lymphoid leukemia(ALL)were the most common causes.Significantly,a considerable proportion of cases of pancytopenia can be attributed to acute leukemia.Hence,expeditious and accurate diagnosis is imperative and has the potential to save lives in such cases. 展开更多
关键词 PANCYTOPENIA LEUKEMIA ANEMIA Bone marrow Blood cells
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