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Demonstrating grating-based phase-contrast imaging of laser-driven shock waves
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作者 Leonard Wegert Stephan Schreiner +16 位作者 Constantin Rauch Bruno Albertazzi Paulina Bleuel Eric Frojdh Michel Koenig Veronika Ludwig Artem SMartynenko Pascal Meyer Aldo Mozzanica Michael Müller Paul Neumayer Markus Schneider Angelos Triantafyllidis Bernhard Zielbauer Gisela Anton Thilo Michel Stefan Funk 《Matter and Radiation at Extremes》 SCIE EI CSCD 2024年第4期90-97,共8页
Single-shot X-ray phase-contrast imaging is used to take high-resolution images of laser-driven strong shock waves.Employing a two-grating Talbot interferometer,we successfully acquire standard absorption,differential... Single-shot X-ray phase-contrast imaging is used to take high-resolution images of laser-driven strong shock waves.Employing a two-grating Talbot interferometer,we successfully acquire standard absorption,differential phase-contrast,and dark-field images of the shocked target.Good agreement is demonstrated between experimental data and the results of two-dimensional radiation hydrodynamics simulations of the laser-plasma interaction.The main sources of image noise are identified through a thorough assessment of the interferometer’s performance.The acquired images demonstrate that grating-based phase-contrast imaging is a powerful diagnostic tool for high-energy-density science.In addition,we make a novel attempt at using the dark-field image as a signal modality of Talbot interferometry to identify the microstructure of a foam target. 展开更多
关键词 INTERACTION shock PHASE
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Inter-annual variations of dissolved oxygen and hypoxia off the northern Changjiang River(Yangtze River) Estuary in summer from 1997 to 2014
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作者 Anqi Liu Feng Zhou +6 位作者 Xiao Ma Qiang Zhao Guanghong Liao Yuntao Zhou Di Tian Xiaobo Ni Ruibin Ding 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第6期119-130,共12页
Hypoxia off the Changjiang River Estuary has been the subject of much attention,yet systematic observations have been lacking,resulting in a lack of knowledge regarding its long-term change and drivers.By revisiting t... Hypoxia off the Changjiang River Estuary has been the subject of much attention,yet systematic observations have been lacking,resulting in a lack of knowledge regarding its long-term change and drivers.By revisiting the repeated surveys of dissolved oxygen(DO) and other relevant hydrographic parameters along the section from the Changjiang River Estuary to the Jeju-do in the summer from 1997 to 2014,rather different trends were revealed for the dual low-DO cores.The nearshore low-DO core,located close to the river mouth and relatively stable,shows that hypoxia has become more severe with the lowest DO descen ding at a rate of -0.07 mg/(L·a) and the thickness of low-DO zone rising at a rate of 0.43 m/a.The offshore core,centered around 40-m isobath but moving back and forth between 123.5°-125°E,shows large fluctuations in the minimum DO concentration,with the thickness of low-DO zone falling at a rate of -1.55 m/a.The probable factors affecting the minimum DO concentration in the two regions also vary.In the nearshore region,the decreasing minimum DO is driven by the increase in both stratification and primary productivity,with the enhanced extension of the Changjiang River Diluted Water(CDW) strengthening stratification.In the offshore region,the fluctuating trend of the minimum DO concentration indicates that both DO loss and DO supplement are distinct.The DO loss is primarily attributed to bottom apparent oxygen utilization caused by the organic matter decay and is also relevant to the advection of low-DO water from the nearshore region.The DO supplement is primarily due to weakened stratification.Our analysis also shows that the minimum DO concentration in the nearshore region was extremely low in 1998,2003,2007 and 2010,related to El Ni?o signal in these summers. 展开更多
关键词 dissolved oxygen low-DO Changjiang River Estuary interannual variations DUAL-CORE
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Memristive feature and mechanism induced by laser-doping in defect-free 2D semiconductor materials
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作者 Xiaoshan Du Shu Wang +11 位作者 Qiaoxuan Zhang Shengyao Chen Fengyou Yang Zhenzhou Liu Zhengwei Fan Lijun Ma Lei Wang Lena Du Zhongchang Wang Cong Wang Bing Chen Qian Liu 《Journal of Semiconductors》 EI CAS CSCD 2024年第7期85-91,共7页
Memristors as non-volatile memory devices have gained numerous attentions owing to their advantages in storage,in-memory computing, synaptic applications, etc. In recent years, two-dimensional(2D) materials with moder... Memristors as non-volatile memory devices have gained numerous attentions owing to their advantages in storage,in-memory computing, synaptic applications, etc. In recent years, two-dimensional(2D) materials with moderate defects have been discovered to exist memristive feature. However, it is very difficult to obtain moderate defect degree in 2D materials, and studied on modulation means and mechanism becomes urgent and essential. In this work, we realized memristive feature with a bipolar switching and a configurable on/off ratio in a two-terminal MoS_(2) device(on/off ratio ~100), for the first time, from absent to present using laser-modulation to few-layer defect-free MoS_(2)(about 10 layers), and its retention time in both high resistance state and low resistance state can reach 2×10^(4) s. The mechanism of the laser-induced memristive feature has been cleared by dynamic Monte Carlo simulations and first-principles calculations. Furthermore, we verified the universality of the laser-modulation by investigating other 2D materials of TMDs. Our work will open a route to modulate and optimize the performance of 2D semiconductor memristive devices. 展开更多
关键词 2D-material memristor laser doping laser direct writing memristive mechanism
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Probiotic interventions in peritoneal dialysis:A review of underlying mechanisms and therapeutic potentials
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作者 Natalia Stepanova 《World Journal of Nephrology》 2024年第4期1-12,共12页
Peritoneal dialysis(PD)is a commonly used modality for kidney replacement therapy for patients with end-stage kidney disease(ESKD).PD offers many benefits,including home-based care,greater flexibility,and preservation... Peritoneal dialysis(PD)is a commonly used modality for kidney replacement therapy for patients with end-stage kidney disease(ESKD).PD offers many benefits,including home-based care,greater flexibility,and preservation of residual kidney function compared to in-center hemodialysis.Nonetheless,patients undergoing PD often face significant challenges,including systemic inflammation,PD-related peritonitis,metabolic disorders,and cardiovascular issues that can negatively affect their quality of life and treatment outcomes.Recent studies have demonstrated the crucial role of the gut microbiome in overall health and treatment results,supporting the hypothesis that probiotics may bring potential benefits to the general population of ESKD patients.However,specific data on probiotic use in PD patients are limited.This opinion review aims to summarize the current knowledge on the relationship between PD and the gut microbiome and offers a novel perspective by specifically exploring how probiotic interventions could improve the outcomes of PD treatment.The review also outlines some clinical data supporting the effectiveness of probiotics in patients undergoing PD and considers the difficulties and restrictions in their application.Based on the current knowledge gaps,this study seeks to explore future research directions and their implications for clinical practice. 展开更多
关键词 Peritoneal dialysis PROBIOTICS GUT MICROBIOTA INFLAMMATION EFFECTIVENESS Treatment
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Rainfall,Landslide and Debris Flow Intergrowth Relationship in Jiangjia Ravine 被引量:5
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作者 HU Mingjian WANG Ren SHEN Jianhua 《Journal of Mountain Science》 SCIE CSCD 2011年第4期603-610,共8页
Jiangjia Ravine is a world-famous debris flow valley in Dongchuan,Yunnan Province,China.Every year large numbers of landslides and collapses happened and caused enormous damages to people's properties and lives.Wi... Jiangjia Ravine is a world-famous debris flow valley in Dongchuan,Yunnan Province,China.Every year large numbers of landslides and collapses happened and caused enormous damages to people's properties and lives.With longtime observation and testing in Jiangjia Ravine we had found out one kind of special landslide which had the characteristics of landslide and collapse.Landslide and collapse supplied sufficient materials for debris flow.When a debris flow broke out,some kind of intergrowth existed among rainfall,landslide and debris flow.In order to study the intergrowth and some key parameters,we carried out artificial rainfall landslide tests and model experiments to observe the phenomena such as collapse,surface slide and surface flow.By observing the experimental phenomena and monitoring water contents,the transformation process among landslide deposits and debris flow under the condition of rainfall had been analyzed.Research results revealed the relationship of this kind of intergrowth among rainfall,landslide and debris flow in Jiangjia Ravine.Meanwhile,it was found that this kind of intergrowth relationship existed only when the moisture content was in a certain range.That is,the critical state seemed to be existed in the transformation process. 展开更多
关键词 LANDSLIDE DEBRIS-FLOW RAINFALL INTERGROWTH Moisture Content Jiangjia Ravine
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A review on therapeutic potential of Nigella sativa:A miracle herb 被引量:18
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作者 Aftab Ahmad Asif Husain +5 位作者 Mohd Mujeeb Shah Alam Khan Abul Kalam Najmi Nasir Ali Siddique Zoheir A.Damanhouri Firoz Anwar 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2013年第5期337-352,共16页
Nigella sativa(N.sativa)(Family Ranunculaceae)is a widely used medicinal plant throughout the world.It is very popular in various traditional systems of medicine like Unani and Tibb,Ayurveda and Siddha.Seeds and oil h... Nigella sativa(N.sativa)(Family Ranunculaceae)is a widely used medicinal plant throughout the world.It is very popular in various traditional systems of medicine like Unani and Tibb,Ayurveda and Siddha.Seeds and oil have a long history of folklore usage in various systems of medicines and food.The seeds of N.saliva have been widely used in the treatment of different diseases and ailments.In Islamic literature,it is considered as one of the greatest forms of healing medicine.It has been recommended for using on regular basis in Tibb-e-Nabwi(Prophetic Medicine).It has been widely used as antihypertensive,liver tonics,diuretics,digestive,anti-diarrheal,appetite stimulant,analgesics,anti-bacterial and in skin disorders.Extensive studies on N.sativa have been carried out by various researchers and a wide spectrum of its pharmacological actions have been explored which may include antidiabetic,anticancer,immunomodulator,analgesic,antimicrobial,anti-inflammatory,spasmolytic,bronchodilator,hepato-protective,renal protective,gaslro-prolective,antioxidant properties,etc.Due to its miraculous power of healing,N.sativa has got the place among the top ranked evidence based herbal medicines.This is also revealed that most of the therapeutic,properties of this plant are due to the presence of thymoquinone which is major bioactive component of the essential oil.The present review is an effort to provide a detailed survey of the literature on scientific researches of pharmacognostical characteristics,chemical composition and pharmacological activities of the seeds of this plant. 展开更多
关键词 Nigella SATIVA MIRACLE HERB RANUNCULACEAE Habat-ul-Sauda THYMOQUINONE Tibb-e-Nabwi Black seeds ANTI-DIABETIC Antioxidant
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Spatial Structure,Hierarchy and Formation Mechanisms of Scientific Collaboration Networks:Evidence of the Belt and Road Regions 被引量:8
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作者 GU Weinan LIU Hui 《Chinese Geographical Science》 SCIE CSCD 2020年第6期959-975,共17页
Scientific collaboration has become an important part of the people-to-people exchanges in the Belt and Road initiative,and remarkable progress has been made since 2013.Taking the 65 countries along the Belt and Road(... Scientific collaboration has become an important part of the people-to-people exchanges in the Belt and Road initiative,and remarkable progress has been made since 2013.Taking the 65 countries along the Belt and Road(BRI countries)as the research areas and using collaborated Web of Science(WOS)core collection papers to construct an international scientific collaboration matrix,the paper explores the spatial structure,hierarchy and formation mechanisms of scientific collaboration networks of 65 countries along the Belt and Road.The results show that:1)Beyond the Belt and Road regions(BRI regions),Central&Eastern Europe,China and West Asia&North Africa have formed a situation in which they all have the most external links with other countries beyond BRI regions.China has the dominant role over other BRI countries in generating scientific links.The overall spatial structure has changed to a skeleton structure consisting of many dense regions,such as Europe,North America,East Asia and Oceania.2)Within the Belt and Road regions,Central&Eastern Europe has become the largest collaboration partner with other sub-regions in BRI countries.The spatial structure of scientific collaboration networks has transformed from the‘dual core’composed of China and the Central&Eastern Europe region,to the‘multi-polarization’composed of‘one zone and multi-points’.3)The hierarchical structure of scientific collaboration networks presents a typical‘core-periphery’structure,and changes from‘single core’to‘double cores’.4)Among the formation mechanisms of scientific collaboration networks,scientific research strength and social proximity play the most important roles,while geographical distance gradually weakens the hindrance to scientific collaboration. 展开更多
关键词 scientific collaboration networks spatial structure HIERARCHY formation mechanisms the Belt and Road regions
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Microwave-assisted synthesis of defective tungsten trioxide for photocatalytic bacterial inactivation:Role of the oxygen vacancy 被引量:6
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作者 Wenquan Gu Wanjun Wang +3 位作者 Guiying Li Haojing Xiea Po Keung Wong Taicheng An 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第10期1488-1497,共10页
Surface defect modulation has emerged as a potential strategy for promoting the photocatalytic activity of photocatalysts for various applications, while the impact of the oxygen vacancy on bacterial inactivation is s... Surface defect modulation has emerged as a potential strategy for promoting the photocatalytic activity of photocatalysts for various applications, while the impact of the oxygen vacancy on bacterial inactivation is still debated. In this study, oxygen vacancies were introduced to tungsten trioxide nanosheets(WO3–x) via a microwave-assisted route. The as-prepared WO3–x nanosheets exhibited excellent visible-light-driven photocatalytic activity toward E. coli K-12 inactivation, and 6 log orders of the bacterial cells could be completely inactivated within 150 min. The obtained bacterial inactivation rate constant was 15.2 times higher than that of pristine WO3 without oxygen vacancies, suggesting that the surface oxygen vacancy could significantly promote the bacterial inactivation efficiency. The mechanism study indicated that the inactivation of bacterial cells occurs via a direct h+ oxidation pathway. In addition, the role of the oxygen vacancy was studied in detail;the oxygen vacancy was found to not only promote interfacial charge separation but also tune the band structure of WO3, thereby leading to increased h+ oxidation power. Finally, a possible oxygen vacancy-dominated photocatalytic bacterial inactivation mechanism is proposed. This work is expected to offer new insights into the microwave-assisted synthesis of defective photocatalysts and the use of the oxygen vacancy for promoting photocatalytic antibacterial activities. 展开更多
关键词 PHOTOCATALYSIS WO3 MICROWAVE Oxygen vacancy Bacterial inactivation
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Molecular mechanisms underlying the neuroprotection of environmental enrichment in Parkinson’s disease 被引量:4
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作者 Tamara Andrea Alarcón Sarah Martins Presti-Silva +2 位作者 Ana Paula Toniato Simões Fabiola Mara Ribeiro Rita Gomes Wanderley Pires 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第7期1450-1456,共7页
Parkinson’s disease is the most common movement disorder,affecting about 1%of the population over the age of 60 years.Parkinson’s disease is characterized clinically by resting tremor,bradykinesia,rigidity and postu... Parkinson’s disease is the most common movement disorder,affecting about 1%of the population over the age of 60 years.Parkinson’s disease is characterized clinically by resting tremor,bradykinesia,rigidity and postural instability,as a result of the progressive loss of nigrostriatal dopaminergic neurons.In addition to this neuronal cell loss,Parkinson’s disease is characterized by the accumulation of intracellular protein aggregates,Lewy bodies and Lewy neurites,composed primarily of the proteinα-synuclein.Although it was first described almost 200 years ago,there are no disease-modifying drugs to treat patients with Parkinson’s disease.In addition to conventional therapies,non-pharmacological treatment strategies are under investigation in patients and animal models of neurodegenerative disorders.Among such strategies,environmental enrichment,comprising physical exercise,cognitive stimulus,and social interactions,has been assessed in preclinical models of Parkinson’s disease.Environmental enrichment can cause structural and functional changes in the brain and promote neurogenesis and dendritic growth by modifying gene expression,enhancing the expression of neurotrophic factors and modulating neurotransmission.In this review article,we focus on the current knowledge about the molecular mechanisms underlying environmental enrichment neuroprotection in Parkinson’s disease,highlighting its influence on the dopaminergic,cholinergic,glutamatergic and GABAergic systems,as well as the involvement of neurotrophic factors.We describe experimental pre-clinical data showing how environmental enrichment can act as a modulator in a neurochemical and behavioral context in different animal models of Parkinson’s disease,highlighting the potential of environmental enrichment as an additional strategy in the management and prevention of this complex disease. 展开更多
关键词 ACETYLCHOLINE brain-derived neurotrophic factor DOPAMINE environment enrichment gamma-aminobutyric acid glial cell line-derived neurotrophic factor GLUTAMATE molecular mechanisms Parkinson’s disease
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Application of Stable Isotope Techniques in Studies of Carbon and Nitrogen Biogeochemical Cycles of Ecosystem 被引量:7
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作者 SUN Zhigao MOU Xiaojie +3 位作者 LI Xinhua WANG Lingling SONG Hongli JIANG Huanhuan 《Chinese Geographical Science》 SCIE CSCD 2011年第2期129-148,共20页
Stable isotope techniques have been proved useful as tools for studying the carbon (C) and nitrogen (N) biogeochemical cycles of ecosystem. This paper firstly introduced the basic principles and the distribution chara... Stable isotope techniques have been proved useful as tools for studying the carbon (C) and nitrogen (N) biogeochemical cycles of ecosystem. This paper firstly introduced the basic principles and the distribution characteristics of stable isotope, then reviewed the recent advances and applications of stable isotope in the C and N biogeochemical cycles of ecosystem. By applying the 13 C natural abundance technique, ecologists are able to understand the photosynthetic path and CO 2 fixation of plants, the CO 2 exchange and C balance status of ecosystem, the composition, distribution and turnover of soil organic C and the sources of organic matter in food webs, while by using the 13 C labeled technique, the effects of elevated CO 2 on the C processes of ecosystem and the sources and fate of organic matter in ecosystem can be revealed in detail. Differently, by applying the 15 N natural abundance technique, ecologists are able to analyze the biological N 2 -fixation, the N sources of ecosystem, the N transformation processes of ecosystem and the N trophic status in food webs, while by using the 15 N labeled technique, the sources, transformation and fate of N in ecosystem and the effects of N input on the ecosystem can be investigated in depth. The applications of both C and N isotope natural abundance and labeled techniques, combined with the elemental, other isotope ( 34 S) and molecular biomarker information, will be more propitious to the investigation of C and N cycle mechanisms. Finally, this paper concluded the problems existed in current researches, and put forward the perspective of stable isotope techniques in the studies on C and N biogeochemical cycles of ecosystem in the future. 展开更多
关键词 stable isotope isotope fractionation isotope natural abundance biogeochemical cycle CARBON NITROGEN
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From trash to treasure: Chemical recycling and upcycling of commodity plastic waste to fuels, high-valued chemicals and advanced materials 被引量:8
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作者 Fan Zhang Fang Wang +4 位作者 Xiangyue Wei Yang Yang Shimei Xu Dehui Deng Yu-Zhong Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第6期369-388,I0011,共21页
Of all the existing materials, plastics are no doubt among the most versatile ones. However, the extreme increases in plastic production as well as the difficulty of the material for degradation have led to a huge num... Of all the existing materials, plastics are no doubt among the most versatile ones. However, the extreme increases in plastic production as well as the difficulty of the material for degradation have led to a huge number of plastic wastes. Their recycling rate after disposal is less than 10%, resulting in a series of serious environmental and ecological problems as well as a significant waste of resources. Current recycling methods generally suffer from large energy consumption, the low utilization rate of recycled products with low added value, and produce other waste during the process. Here, we summarized recentlydeveloped chemical recycling ways on commodity plastics, especially new catalytic paths in production of fuels, high-valued chemicals and advanced materials from a single virgin or a mixture of plastic waste,which have emerged as promising ways to valorize waste plastics more economically and environmentally friendly. The new catalyst design criteria as well as innovative catalytic paths and technologies for plastic upcycling are highlighted. Beyond energy recovery by incineration, these approaches demonstrate how waste plastics can be a viable feedstock for energy use with the generation of clean H_(2), high-quality liquid fuels and materials for energy storage, and help inspiring more catalytic process on plastic upcycling to overcome the economical hurdle and building a circular plastic economy. 展开更多
关键词 Chemical recycling Upcycling Commodity plastic Sustainable development Catalytic path
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Thermal safety of dendritic lithium against non-aqueous electrolyte in pouch-type lithium metal batteries 被引量:6
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作者 Feng-Ni Jiang Shi-Jie Yang +7 位作者 Xin-Bing Cheng Peng Shi Jun-Fan Ding Xiang Chen Hong Yuan Lei Liu Jia-Qi Huang Qiang Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第9期158-165,I0005,共9页
A quantitative relationship between safety issues and dendritic lithium(Li) has been rarely investigated yet. Herein the thermal stability of Li deposits with distinct surface area against non-aqueous electrolyte in p... A quantitative relationship between safety issues and dendritic lithium(Li) has been rarely investigated yet. Herein the thermal stability of Li deposits with distinct surface area against non-aqueous electrolyte in pouch-type Li metal batteries is probed. The thermal runaway temperatures of Li metal batteries obtained by accelerating rate calorimeter are reduced from 211 ℃ for Li foil to 111 ℃ for cycled Li.The initial exothermic temperature is reduced from 194 ℃ for routine Li foil to 142 ℃ for 49.5 m~2g^(-1) dendrite. Li with different specific surface areas can regulate the reaction routes during the temperature range from 50 to 300 ℃. The mass percent of Li foil and highly dendritic Li reacting with ethylene carbonate is higher than that of moderately dendritic Li. This contribution can strengthen the understanding of the thermal runaway mechanism and shed fresh light on the rational design of safe Li metal batteries. 展开更多
关键词 Pouch-type cell Battery safety Lithium metal anode Lithium dendrite growth Thermal runaway
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Fully Fabric-Based Triboelectric Nanogenerators as Self-Powered Human-Machine Interactive Keyboards 被引量:8
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作者 Jia Yi Kai Dong +4 位作者 Shen Shen Yang Jiang Xiao Peng Cuiying Ye Zhong Lin Wang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第7期42-54,共13页
Combination flexible and stretchable textiles with self-powered sensors bring a novel insight into wearable functional electronics and cyber security in the era of Internet of Things.This work presents a highly flexib... Combination flexible and stretchable textiles with self-powered sensors bring a novel insight into wearable functional electronics and cyber security in the era of Internet of Things.This work presents a highly flexible and self-powered fully fabric-based triboelectric nanogenerator(F-TENG)with sandwiched structure for biomechanical energy harvesting and real-time biometric authentication.The prepared F-TENG can power a digital watch by low-frequency motion and respond to the pressure change by the fall of leaves.A self-powered wearable keyboard(SPWK)is also fabricated by integrating large-area F-TENG sensor arrays,which not only can trace and record electrophysiological signals,but also can identify individuals’typing characteristics by means of the Haar wavelet.Based on these merits,the SPWK has promising applications in the realm of wearable electronics,self-powered sensors,cyber security,and artificial intelligences. 展开更多
关键词 Triboelectric nanogenerators Self-powered keyboard Human-machine interface Wearable electronics Fully fabric-based
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Wear Mechanism of WC-Co Cemented Carbide Tool in Cutting Ti-6Al-4V Based on Thermodynamics 被引量:2
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作者 HU Xiaolong SHAO Fang WANG Renwei 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2020年第5期973-979,共7页
In order to optimize the tool coating material and reduce the tool wear rate,the coating material and wear mechanism for carbide tools are proposed and analyzed based on thermodynamics theory.We deduced the Gibbs free... In order to optimize the tool coating material and reduce the tool wear rate,the coating material and wear mechanism for carbide tools are proposed and analyzed based on thermodynamics theory.We deduced the Gibbs free energy function method and analyzed the enthalpy value of the coating material of cemented carbide tools.The rules of diffusion wear and oxidation wear for WC-Co-based carbide tools were analyzed based on the diffusion dissolution theory and the calculation method of the thermal effect of chemical reaction.The diffusion wear and oxidation wear of WC-Co-based carbide tools when machining Ti-6Al-4V were studied with SEM-EDS.The results indicate that a good prediction accuracy of both diffusion wear and oxidation wear can be achieved by the method of thermodynamic theory analysis method.The conclusion will provide useful references for the optimization of cutting parameters and the improvement of the tool life. 展开更多
关键词 cemented carbide THERMODYNAMICS titanium alloy wear mechanism
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Landslide susceptibility modeling based on ANFIS with teaching-learning-based optimization and Satin bowerbird optimizer 被引量:14
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作者 Wei Chen Xi Chen +2 位作者 Jianbing Peng Mahdi Panahi Saro Lee 《Geoscience Frontiers》 SCIE CAS CSCD 2021年第1期93-107,共15页
As threats of landslide hazards have become gradually more severe in recent decades,studies on landslide prevention and mitigation have attracted widespread attention in relevant domains.A hot research topic has been ... As threats of landslide hazards have become gradually more severe in recent decades,studies on landslide prevention and mitigation have attracted widespread attention in relevant domains.A hot research topic has been the ability to predict landslide susceptibility,which can be used to design schemes of land exploitation and urban development in mountainous areas.In this study,the teaching-learning-based optimization(TLBO)and satin bowerbird optimizer(SBO)algorithms were applied to optimize the adaptive neuro-fuzzy inference system(ANFIS)model for landslide susceptibility mapping.In the study area,152 landslides were identified and randomly divided into two groups as training(70%)and validation(30%)dataset.Additionally,a total of fifteen landslide influencing factors were selected.The relative importance and weights of various influencing factors were determined using the step-wise weight assessment ratio analysis(SWARA)method.Finally,the comprehensive performance of the two models was validated and compared using various indexes,such as the root mean square error(RMSE),processing time,convergence,and area under receiver operating characteristic curves(AUROC).The results demonstrated that the AUROC values of the ANFIS,ANFIS-TLBO and ANFIS-SBO models with the training data were 0.808,0.785 and 0.755,respectively.In terms of the validation dataset,the ANFISSBO model exhibited a higher AUROC value of 0.781,while the AUROC value of the ANFIS-TLBO and ANFIS models were 0.749 and 0.681,respectively.Moreover,the ANFIS-SBO model showed lower RMSE values for the validation dataset,indicating that the SBO algorithm had a better optimization capability.Meanwhile,the processing time and convergence of the ANFIS-SBO model were far superior to those of the ANFIS-TLBO model.Therefore,both the ensemble models proposed in this paper can generate adequate results,and the ANFIS-SBO model is recommended as the more suitable model for landslide susceptibility assessment in the study area considered due to its excellent accuracy and efficiency. 展开更多
关键词 Landslide susceptibility Step-wise weight assessment ratio analysis Adaptive neuro-fuzzy fuzzy inference system Teaching-learning-based optimization Satin bowerbird optimizer
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Economic development, energy demand, and carbon emission prospects ofChina's provinces during the 14th Five-Year Plan period: Application ofCMRCGE model 被引量:2
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作者 LI Ji-Feng GU A-Lun +2 位作者 MA Zhong-Yu ZHANG Cheng-Long SUN Zhen-Qing 《Advances in Climate Change Research》 SCIE CSCD 2019年第3期165-173,共9页
This study focuses on a national regional coordinated development strategy and adopts China Multi-Regional Computable General Equilibrium model to analyze the economic and social development, energy demand, and carbon... This study focuses on a national regional coordinated development strategy and adopts China Multi-Regional Computable General Equilibrium model to analyze the economic and social development, energy demand, and carbon emissions of the provinces during the 14th Five-Year Plan (FYP, 2021 2025) period based on the economic development and energy demand since the New Normal. The main conclusions are the following: 1) Under the guidance of the regional coordinated development strategy, 13 provinces/municipalities are expected to have a per capita gross domestic product (GDP) of more than US$15,000, and 16 provinces/municipalities will have a per capita GDP of US$10,000 15,000. All provincial economies are expected to achieve steady and rapid development by the end of the 14th FYP. 2) The total energy consumption of the provinces is expected to reach 5.45 Gtce (excluding Tibet) in 2025, and the average annual growth rate is approximately 1.5%. The growth of energy demand will remain in low speed. The key point of energy demand will gradually shift from the eastern to the middle area, while the proportion of energy use in the western provinces will remain stable, which is consistent with the economic development stage and regional coordinated development strategy. 3) The annual average carbon intensity (mainly considering carbon emissions from energy use) of the provinces will approximately with most provinces dropping by over 4.0%. The trend of a considerable decline in carbon intensity, as observed in recent years, is expected to continue. 展开更多
关键词 Coordinated development CMRCGE model 14th Five-Year Plan Energy demand Carbon emissions
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Thermodynamic and kinetic of iodine-iodide leaching in gold hydrometallurgy 被引量:4
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作者 S.S.KONYRATBEKOVA A.BAIKONUROVA +2 位作者 G.A.USSOLTSEVA C.ERUST A.AKCIL 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第11期3774-3783,共10页
The thermodynamic equilibria and kinetic aspect of gold dissolution in iodine-iodide leaching were studied with emphasis on the effects of pH value and temperature on the system.The results of thermodynamic analysis o... The thermodynamic equilibria and kinetic aspect of gold dissolution in iodine-iodide leaching were studied with emphasis on the effects of pH value and temperature on the system.The results of thermodynamic analysis of iodine in aqueous solution were given and numerous forms of iodine exist mainly in the acid region of pH values.An increase of the potential of the system results in an increase of iodine speciation.The oxidizing potential of the system will increase by the addition of element iodine.The IO^(3-)anions are stable in the potential range from-2.0 to-0.75 V and at pH value greater than 12.1.An increase of the temperature shifts boundaries of existence of various iodine species in the acid region of pH values.Some of them become unstable.The determined values of the diffusion coefficients and the thickness of the diffusion boundary layer,as well as the solvent concentration on the disc surface(14 mg/L) indicate that the process proceeds in the external diffusion region.Thus,while choosing the conditions of leaching from gold-containing materials of different origins of iodide solvents,it is necessary to carry out the process within the acidic region of pH values,where I^-,I_3^- and IO_4^- ions are capable to form complex compounds with metals. 展开更多
关键词 GOLD HYDROMETALLURGY iodine-iodide leaching non-cyanide lixiviants
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Overview of surface ozone variability in East Asia-North Pacific region during IGAC/APARE(1994—1996) 被引量:4
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作者 K.S. Lam T.J.Wang +4 位作者 T. Wang J. Tang . Y.Kajii C.M. Liu S.G. Shim 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第4期599-609,共11页
Surface ozone(O\-3) was measured at Oki Island(Japan), Cheju Island(South Korea), Lanyu Island(Taiwan Province, China), Cape D'Aguilar(Hong Kong SAR) and Lin'an, Longfenshan, Waliguan(China mainland) during J... Surface ozone(O\-3) was measured at Oki Island(Japan), Cheju Island(South Korea), Lanyu Island(Taiwan Province, China), Cape D'Aguilar(Hong Kong SAR) and Lin'an, Longfenshan, Waliguan(China mainland) during January 1994—December 1996 as a component of IGAC/APARE(International Global Atmospheric Chemistry/East Asia-North Pacific Regional Experiment). This paper gave a joint discussion on the observational results at these stations over the study region. Investigations showed that the average of surface O 3 mixing ratios at the seven sites are 47.9±15.8, 48.1±17.9, 30.2±16.4, 31.6±17.5, 36.3±17.5, 34.8±11.5 and 48.2±9.5 ppbv, respectively. Significant diurnal variations of surface O 3 have been observed at Oki, Cheju, D’Aguilar, Lin'an and Longfenshan. Their annual averaged diurnal differences range from 8 to 23 ppbv and differ in each season. Surface O 3 at Lanyu and Waliguan do not show strong diurnal variability. Seasonal cycles of surface O 3 showed difference at the temperate and the subtropical remote sites. Oki has a summer minimum-spring maximum, while Lanyu has a summer minimum-autumn maximum. The suburban sites at D'Aguilar and Lin'an report high-level O 3 in autumn and low level O 3 in summer. Surface O 3 remains high in autumn and low in winter at the rural site Longfenshan. For the global background station Waliguan, surface O 3 exhibits a broad spring-summer maximum and autumn-winter minimum. The backward air trajectories to these sites have shown different pathways of long-range transport of air pollution from East Asia Continent to North Pacific Ocean. Surface O 3 was found to be strongly and positively correlated with CO at Oki and Lanyu, especially in spring and autumn, reflecting the substantial photochemical buildup of O\-3 on a regional scale. It is believed that the regional sources of pollution in East Asia have enhanced the average surface O 3 concentrations in the background atmosphere of North Pacific. 展开更多
关键词 surface ozone TRAJECTORY transport PHOTOCHEMISTRY
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Mechanism of the December 2015 Catastrophic Landslide at the Shenzhen Landfill and Controlling Geotechnical Risks of Urbanization 被引量:75
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作者 Yueping Yin Bin Li +7 位作者 Wenpei Wang Liangtong Zhan Qiang Xue Yang Gao Nan Zhang Hongqi Chen Tiankui Liu Aiguo Li 《Engineering》 SCIE EI 2016年第2期230-249,共20页
This paper presents findings from an investigation of the large-scale construction solid waste (CSW) landslide that occurred at a landfill at Shenzhen, Guangdong, China, on December 20, 2015, and which killed 77 peo... This paper presents findings from an investigation of the large-scale construction solid waste (CSW) landslide that occurred at a landfill at Shenzhen, Guangdong, China, on December 20, 2015, and which killed 77 people and destroyed 33 houses. The landslide involved 2.73 - 106 m3 of CSW and affected an area about 1100 m in length and 630 m in maximum width, making it the largest landfill landslide in the world. The investigation of this disaster used a combination of unmanned aerial vehicle surveillance and multistage remote-sensing images to reveal the increasing volume of waste in the landfill and the shifting shape of the landfill slope for nearly two years before the landslide took place, beginning with the creation of the CSW landfill in March, 2014, that resulted in the uncertain conditions of the landfill's boundaries and the unstable state of the hydrologic performance. As a result, applying conventional stability analysis methods used for natural landslides to this case would be difficult. In order to analyze this disaster, we took a multistage modeling technique to analyze the varied characteristics of the land- fill slope's structure at various stages of CSW dumping and used the non-steady flow theory to explain the groundwater seepage problem. The investigation showed that the landfill could be divided into two units based on the moisture in the land: (1) a front uint, consisted of the landfill slope, which had low water content; and (2) a rear unit, consisted of fresh waste, which had a high water content. This struc- ture caused two effects-surface-water infiltration and consolidation seepage that triggered the landslide in the landfill. Surface-water infiltration induced a gradual increase in pore water pressure head, or piezometric head, in the front slope because the infiltrating position rose as the volume of waste placement increased. Consolidation seepage led to higher excess pore water pressures as the loading of waste increased. We also investigated the post-failure soil dynamics parameters of the landslide deposit using cone penetration, triaxial, and ring-shear tests in order to simulate the characteristics of a flowing slide with a long run-out due to the liquefaction effect. Finally, we conclude the paper with lessons from the tens of catastrophic landslides of municipal solid waste around the world and discuss how to better manage the geotechnical risks of urbanization. 展开更多
关键词 Construction solid waste (CSW)Landfill landslideFactor of safety (FOS)Geotechnical risk
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Storability of “Jonagold” Apple Fruit under Extreme Controlled Atmosphere Conditions 被引量:1
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作者 Adriano Arriel Saquet 《Journal of Agricultural Science and Technology(B)》 2016年第4期262-268,共7页
In two consecutive seasons, the storage capacity of “Jonagold” apple fruit was investigated under regular air (RA) and various controlled atmosphere (CA) conditions during six months at 0 ± 0.3 °C. The dif... In two consecutive seasons, the storage capacity of “Jonagold” apple fruit was investigated under regular air (RA) and various controlled atmosphere (CA) conditions during six months at 0 ± 0.3 °C. The different CA treatment combinations were: (1) 0.5 kPa O2 + 0.5 kPa CO2, (2) 2.0 kPa O2 + 1.0 kPa CO2, (3) 1.0 kPa O2 + 3.0 kPa CO2 and (4) 0.5 kPa O2 + 6.0 kPa CO2. Ethylene production and respiration rate were evaluated at each two months storage intervals during 7 d shelf life at 20 °C. Fruit quality traits were analyzed immediately at the end of storage period and after 7 d shelf life at 20 °C. Under CA treatment, the lower the O2 and/or the higher the CO2 partial pressure, the stronger was the inhibition of the ethylene production and respiration rate of apple fruit. The 0.5 kPa O2 + 6.0 kPa CO2 CA condition induced the strongest suppression in ethylene production and consequently lower CO2 release by apple fruit. At the end of storage period, “Jonagold” apple fruit was very tolerant to all CA conditions, and any kind of internal storage disorders was observed. The storage of “Jonagold” apple at 1.0 kPa O2 + 3.0 kPa CO2 and 0.5 kPa O2 + 6.0 kPa CO2 proportionated higher flesh firmness (FF), greener skin color (SC) and higher titratable acidity (TA) either immediately after storage or after 7 d shelf life at 20 °C. Total soluble solids were not significantly affected by CA storage conditions. 展开更多
关键词 Carbon dioxide “Jonagold” APPLE controlled atmosphere CONDITIONS FRUIT quality ultra-low oxygen
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