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Cassiterite U-Pb dating of the Yelonggou pegmatite-type lithium deposit in western Sichuan and its metallogenic age constraints
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作者 Xiang-yuan Yue Qian Zhang +4 位作者 Jun-jun Zhang Wei Zhang Jing Zhang Zhi-quan Jia Li-ping Luo 《China Geology》 CAS CSCD 2024年第1期153-156,共4页
1.Objective Pegmatite hosts important resource of rare metals,e.g.,lithium(Li)and beryllium(Be).In recent years,increasingly more studies were dedicated to characterize and unravel the formation of pegmatite-type depo... 1.Objective Pegmatite hosts important resource of rare metals,e.g.,lithium(Li)and beryllium(Be).In recent years,increasingly more studies were dedicated to characterize and unravel the formation of pegmatite-type deposits,for which accurate dating of pegmatite formation and mineralization is essential.The Songpan-Ganzi orogenic belt is a major rare metal metallogenic belt in China,hosting many important pegmatite-type Li deposits,including the Lijiagou,Dangba,Jiajika,Yelonggou,Cuola,and Declalongba.Radiometric age data(mica Ar-Ar and zircon/cassiterite U-Pb)from these Li deposits are sparse,ranging from 210 to 152 Ma.However,obtaining reliable zircon U-Pb dates can be a challenge due to the strong decidualization in pegmatites.As a result,the formation and mineralization ages of these rare metal pegmatites remain controversial,which hampers the development of pegmatite-type metallogenic model for the Songpan-Ganzi orogenic belt. 展开更多
关键词 DATING METALLOGENIC ZIRCON
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Progress of Materials and Devices for Neuromorphic Vision Sensors 被引量:4
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作者 Sung Woon Cho Chanho Jo +1 位作者 Yong-Hoon Kim Sung Kyu Park 《Nano-Micro Letters》 SCIE EI CAS CSCD 2022年第12期239-271,共33页
The latest developments in bio-inspired neuromorphic vision sensors can be summarized in 3 keywords:smaller,faster,and smarter.(1)Smaller:Devices are becoming more compact by integrating previously separated component... The latest developments in bio-inspired neuromorphic vision sensors can be summarized in 3 keywords:smaller,faster,and smarter.(1)Smaller:Devices are becoming more compact by integrating previously separated components such as sensors,memory,and processing units.As a prime example,the transition from traditional sensory vision computing to in-sensor vision computing has shown clear benefits,such as simpler circuitry,lower power consumption,and less data redundancy.(2)Swifter:Owing to the nature of physics,smaller and more integrated devices can detect,process,and react to input more quickly.In addition,the methods for sensing and processing optical information using various materials(such as oxide semiconductors)are evolving.(3)Smarter:Owing to these two main research directions,we can expect advanced applications such as adaptive vision sensors,collision sensors,and nociceptive sensors.This review mainly focuses on the recent progress,working mechanisms,image pre-processing techniques,and advanced features of two types of neuromorphic vision sensors based on near-sensor and in-sensor vision computing methodologies. 展开更多
关键词 In-sensor computing Near-sensor computing Neuromorphic vision sensor Optoelectronic synaptic circuit Optoelectronic synapse
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In-situ electrochemical functionalization of carbon materials for high-performance Li–O2 batteries
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作者 Jungwon Kang Jin Min Kim +4 位作者 Do Youb Kim Jungdon Suk Jaekook Kim Dong Wook Kim Yongku Kang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第9期7-13,I0001,共8页
The development of effective synthetic routes is important to manifest proper nature of specific materials.In-situ electrochemical functionalization possesses great advantages over conventional routes,especially facil... The development of effective synthetic routes is important to manifest proper nature of specific materials.In-situ electrochemical functionalization possesses great advantages over conventional routes,especially facile way and leading to reaching elaborate sites of functional group.Here,we demonstrate the preparation of functionalized carbons by in-situ electrochemical reduction in an argon atmosphere for application in low-cost,environmentally benign,and high-performance oxygen-electrodes for non-aqueous Li-O2 batteries.A Li-O2 battery with functionalized carbon shows a high discharge capacity(100 times that of pristine carbon),high power and cycling stability.The outstanding performance is attributed to the high O2 affinity of the functionalized carbon surface that facilitates the formation of soluble and diffusible superoxide intermediates by the reduction of the remaining O2 competing with surface growth for Li2O2 formation. 展开更多
关键词 Lithium-oxygen battery High areal capacity Functionalization of carbon ELECTROCHEMISTRY
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Electrodeposited copper oxides with a suppressed interfacial amorphous phase using mixed-crystalline ITO and their enhanced photoelectrochemical performances 被引量:1
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作者 Ji Hoon Choi Hae-Jun Seok +5 位作者 Dongchul Sung Dong Su Kim Hak Hyeon Lee Suklyun Hong Han-Ki Kim Hyung Koun Cho 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第7期277-286,I0007,共11页
The effectiveness of photoelectrochemical(PEC)water splitting is significantly restricted by insufficient light harvesting,rapid charge recombination,and slow water reduction kinetics.Since the presence of amorphous p... The effectiveness of photoelectrochemical(PEC)water splitting is significantly restricted by insufficient light harvesting,rapid charge recombination,and slow water reduction kinetics.Since the presence of amorphous phases in the interfaces hinders the overcome of these inherent limitations,a photoelectrode must be built strategically.Herein,we artificially controlled the crystallographic orientation of indium tin oxide(ITO)to determine the orientation with the smallest lattice mismatch at the Cu_(2)O interface,thus significantly reducing the amorphous phase in the early stage of electrodeposition nucleation.The[222]/[400]mixed orientation ITO primarily exposed the{400}surface planes and accelerated charge transfer by forming an optimal interface with preferentially grown(111)oriented Cu_(2)O and minimized amorphous region.In addition,the ITO surface energy was calculated using density functional theory to theoretically verify which plane is more active for growing the photoactivation layer.The rationally designed ITO/Cu_(2)O/Al-dope Zn O/TiO_(2)/Rh-P device,with each layer serving a specific purpose,achieved a photocurrent density of 8.23 mA cm^(-2)at 0 VRHEunder AM 1.5 G illumination,providing a standard method for effective solar-to-hydrogen conversion photocathodes. 展开更多
关键词 Photoelectrochemical water splitting Cu_(2)O ITO HYDROGEN Surface energy DFT
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Vegetable Oil-Based Nanolubricants in Machining:From Physicochemical Properties to Application 被引量:2
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作者 Xiaotian Zhang Changhe Li +9 位作者 Zongming Zhou Bo Liu Yanbin Zhang Min Yang Teng Gao Mingzheng Liu Naiqing Zhang Zafar Said Shubham Sharma Hafiz Muhammad Ali 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第4期4-42,共39页
Cutting fluid is crucial in ensuring surface quality and machining accuracy during machining.However,traditional mineral oil-based cutting fluids no longer meet modern machining’s health and environmental protection ... Cutting fluid is crucial in ensuring surface quality and machining accuracy during machining.However,traditional mineral oil-based cutting fluids no longer meet modern machining’s health and environmental protection require-ments.As a renewable,pollution-free alternative with excellent processing characteristics,vegetable oil has become an inevitable replacement.However,vegetable oil lacks oxidation stability,extreme pressure,and antiwear proper-ties,which are essential for machining requirements.The physicochemical characteristics of vegetable oils and the improved methods’application mechanism are not fully understood.This study aims to investigate the effects of viscosity,surface tension,and molecular structure of vegetable oil on cooling and lubricating properties.The mechanisms of autoxidation and high-temperature oxidation based on the molecular structure of vegetable oil are also discussed.The study further investigates the application mechanism and performance of chemical modification and antioxidant additives.The study shows that the propionic ester of methyl hydroxy-oleate obtained by epoxidation has an initial oxidation temperature of 175℃.The application mechanism and extreme pressure performance of conventional extreme pressure additives and nanoparticle additives were also investigated to solve the problem of insufficient oxidation resistance and extreme pressure performance of nanobiological lubricants.Finally,the study discusses the future prospects of vegetable oil for chemical modification and nanoparticle addition.The study provides theoretical guidance and technical support for the industrial application and scientific research of vegetable oil in the field of lubrication and cooling.It is expected to promote sustainable development in the manufacturing industry. 展开更多
关键词 Cutting fluid Vegetable oil Chemical modification ANTIOXIDANT Extreme pressure additive Minimum quality lubrication
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High-Throughput Pb Recycling for Perovskite Solar Cells Using Biomimetic Whitlockite
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作者 Jung Sug Hong Hee Jung Kim +6 位作者 Chang Hwun Sohn Oh Yeong Gong Jin Hyuk Choi Kang Hee Cho Gill Sang Han Ki Tae Nam Hyun Suk Jung 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第3期170-176,共7页
Pb contamination in aquatic environments causes severe pollution;therefore,harmless absorbents are required.In this study,we report a novel synthesis of whitlockite(WH,Ca_(18)Mg_(2)(HPO_(4))_(2)(PO_(4))_(12)),which is... Pb contamination in aquatic environments causes severe pollution;therefore,harmless absorbents are required.In this study,we report a novel synthesis of whitlockite(WH,Ca_(18)Mg_(2)(HPO_(4))_(2)(PO_(4))_(12)),which is the second most abundant biomineral in human bone,and its application as a high-performing Pb^(2+)absorbent.Hydroxyapatite(HAP)and WH are prepared via a simple precipitation method.The Pb2+absorption performance and mechanism of the synthesized biominerals are investigated in aqueous solutions at neutral pH.The results demonstrate that WH exhibits an excellent Pb2+absorption capacity of 2339 mg g^(−1),which is 1.68 times higher than the recorded value for HAP.Furthermore,the absorbed Pb^(2+) ions are recycled into high-purity PbI_(2).This is employed as a precursor for the fabrication of perovskite solar cells(PSCs),resulting in a conversion efficiency of 19.00%comparable to that of commercial PbI2 powder(99.99%purity).Our approach provides an efficient way to remove Pb^(2+)ions from water and reuse them in the recycling of PSCs. 展开更多
关键词 Pb absorption Pb recycling perovskite solar cells water purification whitlockite
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Enhanced Heat Transfer Technology Based on Emission Reduction and Carbon Reduction in Cutting and Grinding
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作者 Changhe Li Yanbin Zhang Shubham Sharma 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第4期1-3,共3页
Huge carbon emissions in machining process,which characterized by high energy consumption and usage of non-renewable resources,is becoming an obsession in the past decades.In the face of the international strategy of ... Huge carbon emissions in machining process,which characterized by high energy consumption and usage of non-renewable resources,is becoming an obsession in the past decades.In the face of the international strategy of carbon peak,it is imperative to eliminate the usage of mineral cutting fluids and reduce energy consumption and carbon emissions by green cutting/grinding technologies,such as dry cutting,minimum quantity lubrication(MQL). 展开更多
关键词 GRINDING LUBRICATION eliminate
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A study of highly activated hydrogen evolution reaction performance in acidic media by 2D heterostructure of N and S doped graphene on MoO_(x)
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作者 Kubra Aydin Seongwon Woo +4 位作者 Vinit Kaluram Kanade Seulgi Choi Chisung Ahn Byungkwon Lim Taesung Kim 《Carbon Energy》 SCIE EI CAS CSCD 2023年第11期68-80,共13页
Herein,a layer of molybdenum oxide(MoO_(x)),a transition metal oxide(TMO),which has outstanding catalytic properties in combination with a carbonbased thin film,is modified to improve the hydrogen production performan... Herein,a layer of molybdenum oxide(MoO_(x)),a transition metal oxide(TMO),which has outstanding catalytic properties in combination with a carbonbased thin film,is modified to improve the hydrogen production performance and protect the MoO_(x)in acidic media.A thin film of graphene is transferred onto the MoO_(x)layer,after which the graphene structure is doped with N and S atoms at room temperature using a plasma doping method to modify the electronic structure and intrinsic properties of the material.The oxygen functional groups in graphene increase the interfacial interactions and electrical contacts between graphene and MoO_(x).The appearance of surface defects such as oxygen vacancies can result in vacancies in MoO_(x).This improves the electrical conductivity and electrochemically accessible surface area.Increasing the number of defects in graphene by adding dopants can significantly affect the chemical reaction at the interfaces and improve the electrochemical performance.These defects in graphene play a crucial role in the adsorption of H^(+)ions on the graphene surface and their transport to the MoO_(x)layer underneath.This enables MoO_(x)to participate in the reaction with the doped graphene.N^(‐)and S^(‐)doped graphene(NSGr)on MoO_(x)is active in acidic media and performs well in terms of hydrogen production.The initial overpotential value of 359 mV for the current density of−10 mA/cm^(2)is lowered to 228 mV after activation. 展开更多
关键词 heteroatom‐doped graphene hydrogen evolution reactions metal‐free catalysts transition metal oxides van der Waals(vdWs)heterostructures
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Interleukin-1 receptor antagonist:From synthesis to therapeutic applications
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作者 KANWAL REHMAN AMMARA AFZAAL +2 位作者 MUHAMMAD SAJID HAMID AKASH MUHAMMAD IMRAN MOHAMMED A.ASSIRI 《BIOCELL》 SCIE 2023年第4期809-823,共15页
The cytokine channel’s mechanism for self-regulation involves the application of antagonistic cytokines that are synthesized to connect to the receptors and release soluble cytokine receptors.The very first receptor ... The cytokine channel’s mechanism for self-regulation involves the application of antagonistic cytokines that are synthesized to connect to the receptors and release soluble cytokine receptors.The very first receptor antagonist of cytokine that was naturally present was interleukin-1 receptor antagonist(IL-1Ra).The IL-1Ra protein forms are disinfected from supernatants of cultured monocytes on stacked IgG.The family of IL-1 consists of IL-1α,IL-1βand IL-1Ra.Human monocytes regulate the production of IL-Ra.IL-Ra takes part in normal physiological functions by using specific antibodies,and acts as an anti-inflammatory agent.IL-Ra is synthesized in the tissues during the period of active disease and can be systematically measured and/or estimated.Maintenance of the levels of IL-Ra and IL-1 is the main factor for host resistance in patients during diseased conditions,as IL-Ra acts as an inherent regulator of various inflammatory responses.In this article,we focuse on how IL-Ra is synthesized and performs its functions once the inflammatory responses are activated. 展开更多
关键词 IL-Ra SYNTHESIS Therapeutic applications Functions of IL-1Ra
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Biochemical association between the prevalence of genetic polymorphism and myocardial infarction
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作者 MOMINA SHAHID KANWAL REHMAN +4 位作者 MUHAMMAD SAJID HAMID AKASH SHALEEM SUHAIL SUMBAL RASHEED MUHAMMAD IMRAN MOHAMMED AASSIRI 《BIOCELL》 SCIE 2023年第3期473-484,共12页
Genetic polymorphism has a vital role in the pathogenesis and development of myocardial infarction(MI).Single nucleotide polymorphism at any one of the amino acid sequences can result in a diseased state.A single gene... Genetic polymorphism has a vital role in the pathogenesis and development of myocardial infarction(MI).Single nucleotide polymorphism at any one of the amino acid sequences can result in a diseased state.A single gene can exhibit genetic polymorphism at more than one position giving rise to different variants.Genetic polymorphism of angiotensinogen(AGT)M235T,AGT T174M,and angiotensin-1-converting enzyme(ACE)I/D,endothelial nitric oxide synthase(eNOS),and methylenetetrahydrofolate reductase(MTHFR)can be a risk factor for MI.However,it is important to study the prevalence of genetic polymorphisms of these genes among different populations.MI is influenced by genetic polymorphism of various genes,including AGT,ACE,eNOS,MTHFR,etc.However,the association of genetic polymorphism of these genes varies among different populations,but different ethnic groups could show contradictory results.These genes have shown a positive association with risks of MI in some populations,whereas the results have not been consistent with every ethnic group.In this article,we have summarized the genetic variations in the aforementioned genes and their association with MI. 展开更多
关键词 Endothelial nitric oxide synthase Methylenetetrahydrofolate reductase AGT M235T AGT T174M
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Effects of Porosity on Piezoelectric Characteristics of Polyvinylidene Fluoride Films for Biomedical Applications
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作者 Jack T.Kloster Matthew J.Danley +1 位作者 Victor K.Lai Ping Zhao 《Biomedical Engineering Frontiers》 CAS 2023年第1期92-99,共8页
Objective:The objective of this work is to study the effects of porosity on mechanical and piezoelectric properties of polyvinylidene fluoride(PVDF)films for biomedical applications.Impact Statement:By investigating t... Objective:The objective of this work is to study the effects of porosity on mechanical and piezoelectric properties of polyvinylidene fluoride(PVDF)films for biomedical applications.Impact Statement:By investigating the piezoelectric properties of PVDF and the porosity effect on its electromechanical performance,there is potential for further development of PVDF as a hemodynamic sensor that can lead to further technological advancements in the biomedical field,benefiting patients and physicians alike.Introduction:PVDF thin films have shown potential in the application of hemodynamic flow sensing and monitoring the effects on blood flow caused by prosthetic valve implantation via the transcatheter aortic valve replacement operation.The piezoelectric performance of PVDF films can be influenced by the porosity of the material.Methods:In this study,strain tracking was performed on thin film PVDF specimens with various levels of porosity and pore sizes to determine the mechanical properties of the specimens.The mechanical properties were used to model the PVDF material in COMSOL multiphysics software,in which compression test simulations were performed to determine the piezoelectric coefficient d33 of the PVDF.Results:A decline in the elastic modulus was found to be highly inversely correlated with porosity of the specimens and the simulation results show that elastic modulus had a much greater effect on the piezoelectric properties than Poisson’s ratio.Conclusion:A combination of experimental and computational techniques was able to characterize and correlate the mechanical properties of PVDF films of varying porosities to their piezoelectric properties. 展开更多
关键词 PIEZOELECTRIC POROSITY MODULUS
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A Hybrid Deep Learning Approach to Classify the Plant Leaf Species
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作者 Javed Rashid Imran Khan +3 位作者 Irshad Ahmed Abbasi Muhammad Rizwan Saeed Mubbashar Saddique Mohamed Abbas 《Computers, Materials & Continua》 SCIE EI 2023年第9期3897-3920,共24页
Many plant species have a startling degree of morphological similarity,making it difficult to split and categorize them reliably.Unknown plant species can be challenging to classify and segment using deep learning.Whi... Many plant species have a startling degree of morphological similarity,making it difficult to split and categorize them reliably.Unknown plant species can be challenging to classify and segment using deep learning.While using deep learning architectures has helped improve classification accuracy,the resulting models often need to be more flexible and require a large dataset to train.For the sake of taxonomy,this research proposes a hybrid method for categorizing guava,potato,and java plumleaves.Two new approaches are used to formthe hybridmodel suggested here.The guava,potato,and java plum plant species have been successfully segmented using the first model built on the MobileNetV2-UNET architecture.As a second model,we use a Plant Species Detection Stacking Ensemble Deep Learning Model(PSD-SE-DLM)to identify potatoes,java plums,and guava.The proposed models were trained using data collected in Punjab,Pakistan,consisting of images of healthy and sick leaves from guava,java plum,and potatoes.These datasets are known as PLSD and PLSSD.Accuracy levels of 99.84%and 96.38%were achieved for the suggested PSD-SE-DLM and MobileNetV2-UNET models,respectively. 展开更多
关键词 Plant leaf species stacking ensemble model GUAVA POTATO java plum MobileNetV2-UNET hybrid deep learning segmentation
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Material Removal Mechanism and Force Modeling in Ultrasonic Vibration-Assisted Micro-Grinding Biological Bone
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作者 Jingang Sun Changhe Li +10 位作者 Zongming Zhou Bo Liu Yanbin Zhang Min Yang Teng Gao Mingzheng Liu Xin Cui Benkai Li Runze Li Yusuf Suleiman Dambatta Shubham Sharma 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第5期20-44,共25页
Micro-grinding with a spherical grinding head has been deemed an indispensable method in high-risk surgeries, such as neurosurgery and spine surgery, where bone grinding has long been plagued by the technical bottlene... Micro-grinding with a spherical grinding head has been deemed an indispensable method in high-risk surgeries, such as neurosurgery and spine surgery, where bone grinding has long been plagued by the technical bottleneck of mechanical stress-induced crack damage. In response to this challenge, the ultrasound-assisted biological bone micro-grinding novel process with a spherical grinding head has been proposed by researchers. Force modeling is a prerequisite for process parameter determination in orthopedic surgery, and the difculty in establishing and accurately predicting bone micro-grinding force prediction models is due to the geometric distribution of abrasive grains and the dynamic changes in geometry and kinematics during the cutting process. In addressing these critical needs and technical problems, the shape and protrusion heights of the wear particle of the spherical grinding head were frst studied, and the gradual rule of the contact arc length under the action of high-speed rotating ultrasonic vibration was proposed. Second, the mathematical model of the maximum thickness of undeformed chips under ultrasonic vibration of the spherical grinding head was established. Results showed that ultrasonic vibration can reduce the maximum thickness of undeformed chips and increase the range of ductile and bone meal removals, revealing the mechanism of reducing grinding force. Further, the dynamic grinding behavior of diferent layers of abrasive particles under diferent instantaneous interaction states was studied. Finally, a prediction model of micro-grinding force was established in accordance with the relationship between grinding force and cutting depth, revealing the mechanism of micro-grinding force transfer under ultrasonic vibration. The theoretical model’s average deviations are 10.37% in x-axis direction, 6.85% in y-axis direction, and 7.81% in z-axis direction compared with the experimental results. This study provides theoretical guidance and technical support for clinical bone micro-grinding. 展开更多
关键词 Spherical grinding head Gradual contact arc length Maximum undeformed chip thickness Microgrinding force
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ZnSe-石墨烯/TiO_2声催化剂上罗丹明B降解与反应氧物种生成(英文) 被引量:6
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作者 Lei Zhu Sun-Bok Jo +2 位作者 Shu Ye Kefayat Ullah Won-Chun Oh 《催化学报》 SCIE EI CAS CSCD 北大核心 2014年第11期1825-1832,共8页
Nanostructured ZnSe-graphene/TiO2 was synthesized by a hydrothermal-assisted approach. ZnSe-graphene/TiO2 exhibited favorable adsorption of rhodamine B, a wide wavelength absorption range, and efficient charge ... Nanostructured ZnSe-graphene/TiO2 was synthesized by a hydrothermal-assisted approach. ZnSe-graphene/TiO2 exhibited favorable adsorption of rhodamine B, a wide wavelength absorption range, and efficient charge separation. Reactive oxygen species were generated by the oxidation of 1,5-diphenyl carbazide to 1,5-diphenyl carbazone. The sonocatalytic reaction mechanism was pro-posed. These findings potentially broaden the applications of sonocatalytic technologies. 展开更多
关键词 ZNSE 活性氧 石墨 若丹明B TIO2 降解 二氧化钛 催化反应机理
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超声辅助法合成的石墨烯-TiO_2复合材料声催化降解罗丹明B(英文) 被引量:8
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作者 Trisha GHOSH Chong-Yeon PARK OH Won-Chun 《催化学报》 SCIE EI CAS CSCD 北大核心 2012年第8期1276-1283,共8页
A series of graphene-TiO2 composites was fabricated from graphene oxide and titanium n-butoxide(TNB) by an ultrasonic-assisted method.The structure and composition of the nanocomposites were characterized by Raman spe... A series of graphene-TiO2 composites was fabricated from graphene oxide and titanium n-butoxide(TNB) by an ultrasonic-assisted method.The structure and composition of the nanocomposites were characterized by Raman spectroscopy,BET surface area measurements,X-ray diffraction,transmission electron microscopy,and ultraviolet-visible absorption spectroscopy.The average size of the TiO2 nanoparticles on the graphene nanosheets was controlled at around 10-15 nm without using surfactant,which is attributed to the pyrolysis and condensation of dissolved TNB into TiO2 by ultrasonic irradiation.The catalytic activity of the composites under ultrasonic irradiation was determined using a rhodamine B(RhB) solution.The graphene-TiO2 composites possessed a high specific surface area,which increased the decolorization rate for RhB solution.This is because the graphene and TiO2 nanoparticles in the composites interact strongly,which enhances the photoelectric conversion of TiO2 by reducing the recombination of photogenerated electron-hole pairs. 展开更多
关键词 GRAPHEME ultrasonication sonocatalytic degradation ADSORPTION rhodamine B
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紫外光照射下Fe-碳纳米管/TiO_2复合材料降解罗丹明B(英文) 被引量:6
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作者 OH Wonchun 《催化学报》 SCIE EI CAS CSCD 北大核心 2010年第7期751-758,共8页
The composites comprising Fe-carbon nanotubes(CNTs) on TiO2 were prepared by a modified sol-gel method and characterized by nitrogen adsorption,scanning electron microscopy,transmission electron microscopy,X-ray diffr... The composites comprising Fe-carbon nanotubes(CNTs) on TiO2 were prepared by a modified sol-gel method and characterized by nitrogen adsorption,scanning electron microscopy,transmission electron microscopy,X-ray diffraction,and energy dispersive X-ray analysis.The photocatalytic decomposition of rhodamine B(Rh.B) under UV irradiation and air aeration catalyzed by the composites was measured.The photocatalytic activity of TiO2 nanoparticles was significantly enhanced by the large CNT network that facilitated electron transfer between adsorbed Rh.B molecules and the catalyst substrate and the simultaneous occurrence of the photo-Fenton reaction in the presence of Fe particles.A marked acceleration of the decomposition rate was observed with aeration by flowing air aeration due to the formation of the circulatory photo-Fenton system.Chemical oxygen demand of piggery waste was measured at regular intervals to evaluate the mineralization of wastewater. 展开更多
关键词 IRON carbon nanotube TITANIA rhodamine B photocatalytic activity PHOTO-FENTON
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Effects of porosity and pore size on the compressive properties of closed-cell Mg alloy foam 被引量:8
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作者 X.C.Xia X.W.Chen +4 位作者 Z.Zhang X.Chen W.M.Zhao B.Liao B.Hur 《Journal of Magnesium and Alloys》 SCIE EI CAS 2013年第4期330-335,共6页
In our current work,AZ31 magnesium alloy foams with closed-cell were successfully fabricated by melt foaming method using Ca and CaCO3 as thickening and blowing agent,respectively.The influences of porosity and pore s... In our current work,AZ31 magnesium alloy foams with closed-cell were successfully fabricated by melt foaming method using Ca and CaCO3 as thickening and blowing agent,respectively.The influences of porosity and pore size on the quasi-static compressive properties of the foams were systematically investigated.The results showed that the yield strength,energy absorption capacity and ideality energy absorption efficiency were decreased with the increase in porosity.However,specimens with porosities of 60%,65%and 70%possessed similar total energy absorption capacity and ideality energy absorption efficiency.Meanwhile,experimental results showed that mean plateau strength of the foams was increased first and then decreased with increase in mean pore size.In addition,energy absorption capacities were almost the same in the initial stage,while the differences were obvious in the middle stage.From the engineering point of view,the specimens with mean pore size of 1.5 mm possess good combination of mean plateau strength and energy absorption characteristics under the present conditions. 展开更多
关键词 Metal foam Melt forming method Mg alloy foam Compressive property
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Ag_2S-石墨烯/TiO_2的声化学法合成及可见光催化活性(英文) 被引量:3
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作者 Ze‐Da Meng Lei Zhu +3 位作者 Kefayat Ullah Shu Ye Qian Sun Won‐Chun Oh 《催化学报》 SCIE CAS CSCD 北大核心 2013年第8期1527-1533,共7页
Ag2S‐graphene/TiO2 composites were synthesized by a facile sonochemical method.The products were characterized by X‐ray diffraction,scanning electron microscopy,energy dispersive X‐ray spectroscopy,transmission ele... Ag2S‐graphene/TiO2 composites were synthesized by a facile sonochemical method.The products were characterized by X‐ray diffraction,scanning electron microscopy,energy dispersive X‐ray spectroscopy,transmission electron microscopy,and UV‐Vis diffuse reflectance spectrophotometry.During the synthesis reaction,the reduction of graphene oxide and loading of Ag2S and TiO2 particles were achieved.The Ag2S‐graphene/TiO2 composites possessed a large adsorption capacity for dyes,an extended light absorption range,and efficient charge separation properties.Hence,in the photodegradation of rhodamine B,a significant enhancement in the reaction rate was observed with the Ag2S‐graphene/TiO2 composites as compared to pure TiO2.The generation of reactive oxygen species was detected by the oxidation of 1,5‐diphenyl carbazide to 1,5‐diphenyl carbazone.The high activity was attributed to the synergetic effects of high charge mobility and the red shift in the absorption edge of the Ag2S‐graphene/TiO2 composites. 展开更多
关键词 纳米复合材料 超声合成 扫描电子显微镜 透射电子显微镜 二苯卡巴肼 二氧化钛粒子 射线衍射 氧化石墨
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可见光下具有高光子效应和光催化活性的CuS-石墨烯氧化物/TiO_2复合材料的制备(英文) 被引量:3
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作者 PARK ChongYeon GHOSH Trisha +3 位作者 MENG ZeDa KEFAYAT Ullah VIKRAM Nikam OH WonChun 《催化学报》 SCIE EI CAS CSCD 北大核心 2013年第4期711-717,共7页
CuS-graphene oxide/TiO2 composites were prepared using a sol-gel method to improve the photocatalytic performance of the photocatalyst. The composites were characterized by X-ray diffraction, scanning electron microsc... CuS-graphene oxide/TiO2 composites were prepared using a sol-gel method to improve the photocatalytic performance of the photocatalyst. The composites were characterized by X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray analysis, and transmission electron microscopy. The photocatalytic activities were examined by the degradation of methylene blue (MB) under visible-light irradiation. The photodegradation of MB under visible-light irradiation reached 90.1% after 120 min. The kinetics of MB degradation was plotted alongside the values calculated from the Langmuir-Hinshelwood equation. The CuS-graphene oxide/TiO2 sample prepared using 0.2 mol of TiO2 showed the best photocatalytic activity. This was attributed to a cooperative reaction as a result of increased photoabsorption by graphene oxide and an increased photocatalytic effect by CuS. 展开更多
关键词 Graphene oxide PHOTOCATALYST TITANIA Coper SULFIDE METHYLENE BLUE VISIBLE light
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CoS_2-碳(C_(60),石墨,碳纳米管)/TiO_2复合光敏剂光降解有机染料(英文) 被引量:2
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作者 MENG Zeda OH Wonchun 《催化学报》 SCIE EI CAS CSCD 北大核心 2012年第9期1495-1501,共7页
CoS2,CoS 2-C60 /TiO2,CoS2-CNT/TiO2,and CoS2-Graphene/TiO2 were prepared.The TiO2 products had the anatase phase structure and interesting surface compositions.X-ray diffraction patterns of the CoS2-carbon/TiO2 composi... CoS2,CoS 2-C60 /TiO2,CoS2-CNT/TiO2,and CoS2-Graphene/TiO2 were prepared.The TiO2 products had the anatase phase structure and interesting surface compositions.X-ray diffraction patterns of the CoS2-carbon/TiO2 composites showed a single and clear anatase phase and the CoS2 structure.Scanning electron microscopy characterization of the texture on the CoS 2-carbon/TiO2 composites showed a homogenous composition.Energy-dispersive X-ray spectra for elemental identification showed the presence of C and Ti with strong Co and S peaks from the CoS2-carbon/TiO2 composites.The composites obtained were also characterized by transmission electron microscopy and UV-Vis spectroscopy.CoS2-carbon/TiO2 composites showed excellent photocatalytic activity for the degradation of methylene blue under visible light irradiation.This was attributed to both photocatalysis on the TiO2 support and charge transfer by the carbon nanomaterial,and the introduction of CoS2 to enhance transfer of photogenerated electrons. 展开更多
关键词 FULLERENE carbon NANOTUBE graphene cobalt DISULFIDE titanium dioxide visible light METHYLENE blue PHOTODEGRADATION
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