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Investigation of natural and anthropogenic effects on aerosols optical properties over the Western Pacific ocean by the research vessel KEXUE
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作者 Jinyuan Xin Yining Ma +6 位作者 Xiangguang Zhang Yongjing Ma Xiaoyan Wu Fangkun Wu Quan Liu Yilong Lyu Jiawei Jiang 《Journal of Environmental Sciences》 2026年第1期596-605,共10页
In winter 2018,an aerosol physicochemical experiment was conducted in the Western Pacific Ocean(WPO)aboard the Research Vessel KEXUE of Chinese Academy of Sciences.This study systematically investigated both natural a... In winter 2018,an aerosol physicochemical experiment was conducted in the Western Pacific Ocean(WPO)aboard the Research Vessel KEXUE of Chinese Academy of Sciences.This study systematically investigated both natural and anthropogenic effects on marine aerosols optical properties,as well as the applicability of multi-satellite products and IMPROVE equation.The averaged aerosol optical depth(AOD500 nm)was 0.31±0.16 andÅngström exponent440–675 nm was 0.29±0.30.In offshore China,significant anthropogenic emissions affected the marine environment.In remote WPO,dust aerosols transported from northern China,Siberia,Central Asia,and those settling from the upper troposphere originating from north Africa,Arabian peninsula,and western India,were dominant.The spatial trends of AOD were opposite in the mid-latitude and southern seas of WPO.The highest AOD,0.32±0.23,appeared along the coast of South Asia at mid-latitude,decreasing from offshore seas to remote oceans.In low-latitude and equatorial seas,AOD significantly increased from coast to remote oceans.Ångström exponent dropped significantly from the coast to remote oceans as anthropogenic influence diminished across the entire WPO.Correlation analysis showed that both MODIS-C6 and Himawari AOD prod-ucts showed similar applicability in coastal urban areas,while Himawari AOD is highly recommended for coastal background and marine environment due to its finer resolution.The extinction coefficient derived from PM_(2.5) chemical compositions using IMPROVE algorithm exhibited a significant correlation(R^(2)=0.58)with the con-currently measured AOD in the absence of long-distance transport,suggesting that the IMPROVE is a reasonable proxy of the columnar average of marine aerosol extinctions free from transport influences. 展开更多
关键词 Aerosol optical properties Natural and anthropogenic effects Improve algorithm Ship-borne experiment Western Pacific Ocean
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Lithium Nitrate Effects for Lithium-Based Chemical Batteries:A Review
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作者 Xianshu Wang Junru Wu +6 位作者 Huirong Wang Xiangshao Yin Zhuo Zhou Yuanyuan Huang Yelong Zhang Weishan Li Baohua Li 《Carbon Energy》 2026年第1期197-222,共26页
Lithium metal batteries(LMBs)have been regarded as one of the most promising alternatives in the post-lithium battery era due to their high energy density,which meets the needs of light-weight electronic devices and l... Lithium metal batteries(LMBs)have been regarded as one of the most promising alternatives in the post-lithium battery era due to their high energy density,which meets the needs of light-weight electronic devices and long-range electric vehicles.However,technical barriers such as dendrite growth and poor Li plating/stripping reversibility severely hinder the practical application of LMBs.However,lithium nitrate(LiNO_(3))is found to be able to stabilize the Li/electrolyte interface and has been used to address the above challenges.To date,considerable research efforts have been devoted toward understanding the roles of LiNO_(3) in regulating the surface properties of Li anodes and toward the development of many effective strategies.These research efforts are partially mentioned in some articles on LMBs and yet have not been reviewed systematically.To fill this gap,we discuss the recent advances in fundamental and technological research on LiNO_(3) and its derivatives for improving the performances of LMBs,particularly for Li-sulfur(S),Li-oxygen(O),and Li-Li-containing transition-metal oxide(LTMO)batteries,as well as LiNO_(3)-containing recipes for precursors in battery materials and interphase fabrication.This review pays attention to the effects of LiNO_(3) in lithium-based batteries,aiming to provide scientific guidance for the optimization of electrode/electrolyte interfaces and enrich the design of advanced LMBs. 展开更多
关键词 effects and mechanisms LiNO_(3)derivatives LiNO_(3)-containing recipes lithium metal anode Lithium nitrate basis lithium-based chemical batteries
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Er和Cu复合添加对A356合金组织与力学性能的影响
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作者 汤江涛 冯丽 +3 位作者 冯恩浪 姜岳峰 梁田 马颖澈 《金属热处理》 北大核心 2026年第1期12-21,共10页
通过在A356铝合金中加入0.2%、0.4%稀土元素Er及复合添加0.1%Er、1.76%Cu,研究了Er、Cu对压铸成形A356铝合金微观组织和力学性能的影响。结果表明:加入稀土元素Er后,共晶Si的形貌由长纤维状或长棒状转变为细小的纤维状或点状结构,共晶S... 通过在A356铝合金中加入0.2%、0.4%稀土元素Er及复合添加0.1%Er、1.76%Cu,研究了Er、Cu对压铸成形A356铝合金微观组织和力学性能的影响。结果表明:加入稀土元素Er后,共晶Si的形貌由长纤维状或长棒状转变为细小的纤维状或点状结构,共晶Si的共晶转变温度及α-Al的熔化温度降低。随着Er含量的增加,合金的抗拉强度由242.0 MPa小幅升高至250.0 MPa,但伸长率由7.00%降低至5.50%。在A356铝合金中复合添加0.1%Er和1.76%Cu时,合金中形成了Al_(3)Er、Al_(8)Cu_(4)Er、Al_(2)Cu等金属间化合物,合金的抗拉强度为243.0 MPa,伸长率降低为1.50%,表明Er和Cu未表现出良好的协同强韧化作用。其主要原因是快速凝固促使富Cu相以粗大块状或团簇状在枝晶间析出,导致应力集中,并在拉伸过程中于其棱角处萌生微裂纹,从而严重恶化塑性。 展开更多
关键词 压铸态 A356合金 稀土er CU 复合协同
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Photothermal effects of multidimensional confined MMC/TMs-MDCS catalyst for ultra-high photocatalytic hydrogen evolution 被引量:1
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作者 Huihua Luo Haifeng Zhu +4 位作者 Kehui Xue Chong Liu Nannan Chen Yaping Zhang Lianqing Yu 《Journal of Energy Chemistry》 2025年第5期655-669,共15页
Multidimensional confined structure systems are proposed and demonstrated by using MoO_(2)@MO_(2)C(MMC)to enhance the photothermal catalytic performance of the metal sulfides-multidimensional confined structure(TMs-MD... Multidimensional confined structure systems are proposed and demonstrated by using MoO_(2)@MO_(2)C(MMC)to enhance the photothermal catalytic performance of the metal sulfides-multidimensional confined structure(TMs-MDCS).Specifically,the MMC nanoparticles confined to the surface of the ZnIn_(2)S_(4)hollow tube-shell(MMC/HT-ZIS)achieve a hydrogen evolution rate of 9.72 mmol g^(-1)h^(-1),which is 11.2 times higher than that of pure HT-ZIS.Meanwhile,the MnCdS(MCS)nanoparticles are encapsulated within the two-dimensional MMC(2D MMC/MCS)through precise regulation of size and morphology.The 10-MMC/MCS lamellar network demonstrates the highest hydrogen evolution rate of 8.19 mmol g^(-1)-h^(-1).The obtained MMC/TMs-MDCS catalysts exhibit an enhanced photocatalytic hydrogen evolution rate,which can be attributed to the strong synergistic interaction between the multidimensional confinement and the photothermal effects.The confinement space and the strong interfacial relationship within the MMC/TMs-MDCS create abundant channels and active sites that facilitate electron migration and transport.Furthermore,the construction of a confined environment positions these materials as promising candidates for achieving exceptional photothermal catalytic performance,as MMC/TMs-MDCS enhance light absorption through light scattering and reflecting effects.Additionally,the capacity of MMC/TMsMDCS to convert solar light into thermal energy significantly reduces the activation energy of the reaction,thereby facilitating reaction kinetics and accelerating the separation and transport of photogenerated carriers.This work provides valuable insights for the development of highly efficient photothermal catalytic water-splitting systems for hydrogen production using multidimensional confined catalysts. 展开更多
关键词 Multidimensional confined effect Photothermal effect Photothermal catalytic hydrogen production
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Effects of Fruit-Crop Agroforestry Systems on Pest and Natural Enemy Diversity 被引量:1
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作者 LI Guoyu LIU Tingting +3 位作者 WEI Wenwen ZHANG Shuai LI Zhe ZHANG Wei 《绿洲农业科学与工程》 2025年第1期80-91,共12页
Agricultural intensification has led to an increase in monoculture and the use of chemical pesticides,resulting in a decline in biodiversity and a reduction in ecosystem services,particularly biological pest managemen... Agricultural intensification has led to an increase in monoculture and the use of chemical pesticides,resulting in a decline in biodiversity and a reduction in ecosystem services,particularly biological pest management.However,studies have shown that agroforestry can not only improve land productivity and biodiversity but also regulate some ecosystem services.This study reviews the impacts of physical and biological factors on herbivorous pests,parasites,and predatory natural enemies in fruit-crop agroforestry systems.Fruit-crop agroforestry systems provide high spatial heterogeneity by altering crop layouts,regulating the microclimate and soil quality,and offering food resources and shelter for natural enemies,thus promoting biological pest control.This enhances biological control and makes the agrocomplex system an effective tool for sustainable agriculture.Our research shows that volatile plant substances attract or repel pests and natural enemies based on the characteristics of the insects themselves.When scientifically designed,fruit-crop agroforestry systems provide high spatial heterogeneity and favorable microclimatic conditions,which enhance biological pest control and make the agroforestry system an effective tool for sustainable agriculture.Our research shows that fruit-crop agroforestry systems can provide richer food resources and habitat,enhancing biological pest control and improving pest management. 展开更多
关键词 AGROFORESTRY PEST natural enemy BIODIVerSITY effect factors
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Independent and interactive effects of N and P additions on foliar P fractions in evergreen forests of southern China 被引量:1
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作者 Qingquan Meng Zhijuan Shi +3 位作者 Zhengbing Yan Hans Lambers Yan Luo Wenxuan Han 《Forest Ecosystems》 2025年第1期66-73,共8页
Fertilization or atmospheric deposition of nitrogen(N)and phosphorus(P)to terrestrial ecosystems can alter soil N(P)availability and the nature of nutrient limitation for plant growth.Changing the allocation of leaf P... Fertilization or atmospheric deposition of nitrogen(N)and phosphorus(P)to terrestrial ecosystems can alter soil N(P)availability and the nature of nutrient limitation for plant growth.Changing the allocation of leaf P fractions is potentially an adaptive strategy for plants to cope with soil N(P)availability and nutrient-limiting conditions.However,the impact of the interactions between imbalanced anthropogenic N and P inputs on the concentrations and allocation proportions of leaf P fractions in forest woody plants remains elusive.We conducted a metaanalysis of data about the concentrations and allocation proportions of leaf P fractions,specifically associated with individual and combined additions of N and P in evergreen forests,the dominant vegetation type in southern China where the primary productivity is usually considered limited by P.This assessment allowed us to quantitatively evaluate the effects of N and P additions alone and interactively on leaf P allocation and use strategies.Nitrogen addition(exacerbating P limitation)reduced the concentrations of leaf total P and different leaf P fractions.Nitrogen addition reduced the allocation to leaf metabolic P but increased the allocation to other fractions,while P addition showed opposite trends.The simultaneous additions of N and P showed an antagonistic(mutual suppression)effect on the concentrations of leaf P fractions,but an additive(summary)effect on the allocation proportions of leaf P fractions.These results highlight the importance of strategies of leaf P fraction allocation in forest plants under changes in environmental nutrient availability.Importantly,our study identified critical interactions associated with combined N and P inputs that affect leaf P fractions,thus aiding in predicting plant acclimation strategies in the context of intensifying and imbalanced anthropogenic nutrient inputs. 展开更多
关键词 Anthropogenic nutrient inputs Individual and combined effects Interactive effects Leaf phosphorus fractions Nitrogen and phosphorus additions Nutrient-utilization strategies Woody plants
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Understanding the Decoupled Effects of Cations and Anions Doping for High-Performance Perovskite Solar Cells 被引量:1
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作者 Tianxiang Hu Yixi Wang +16 位作者 Kai Liu Jia Liu Haoyang Zhang Qudrat Ullah Khan Shijie Dai Weifan Qian Ruochen Liu Yanyan Wang Chongyuan Li Zhenru Zhang Mingxiang Luo Xiaofei Yue Chunxiao Cong Yuan Yongbo Anran Yu Jia Zhang Yiqiang Zhan 《Nano-Micro Letters》 2025年第6期411-426,共16页
The past decade has witnessed the rapid increasement in power conversion efficiency of perovskite solar cells(PSCs).However,serious ion migration hampers their operational stability.Although dopants composed of varied... The past decade has witnessed the rapid increasement in power conversion efficiency of perovskite solar cells(PSCs).However,serious ion migration hampers their operational stability.Although dopants composed of varied cations and anions are introduced into perovskite to suppress ion migration,the impact of cations or anions is not individually explored,which hinders the evaluation of different cations and further application of doping strategy.Here we report that a special group of sulfonic anions(like CF_(3)SO_(3)^(-))successfully introduce alkaline earth ions(like Ca^(2+))into perovskite lattice compared to its halide counterparts.Furthermore,with effective crystallization regulation and defect passivation of sulfonic anions,perovskite with Ca(CF_(3)SO_(3))_(2)shows reduced PbI2 residue and metallic Pb0 defects;thereby,corresponding PSCs show an enhanced PCE of 24.95%.Finally by comparing the properties of perovskite with Ca(CF_(3)SO_(3))_(2)and FACF_(3)SO_(3),we found that doped Ca^(2+)significantly suppressed halide migration with an activation energy of 1.246 eV which accounts for the improved operational stability of Ca(CF_(3)SO_(3))_(2-)doped PSCs,while no obvious impact of Ca^(2+)on trap density is observed.Combining the benefits of cations and anions,this study presents an effective method to decouple the effects of cations and anions and fabricate efficient and stable PSCs. 展开更多
关键词 Perovskite solar cells Interstitial doping Effect decoupling Ion migration
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Factors affecting the thermal effects of lasers in lithotripsy:A literature review 被引量:1
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作者 Kiron Krishnaprasad Ravi Teja Pathi Mustafa Nazar 《Asian Journal of Urology》 2025年第1期23-32,共10页
Objective The use of lasers has been an important part of urology in the treatment of stone and prostate disease.The thermal effects of lasers in lithotripsy have been a subject of debate over the years.The objective ... Objective The use of lasers has been an important part of urology in the treatment of stone and prostate disease.The thermal effects of lasers in lithotripsy have been a subject of debate over the years.The objective of this review was to assess the current state of knowledge available on the thermal effects of lasers in lithotripsy,as well as explore any new areas where studies are needed.Methods In August 2022,a keyword search on Google Scholar,PubMed,and Scopus for all papers containing the phrases“thermal effects”AND“laser”AND“lithotripsy”AND“urology”was done followed by citation jumping to other studies pertaining to the topic and 35 relevant papers were included in our study.The data from relevant papers were segregated into five groups according to the factor studied and type of study,and tables were created for a comparison of data.Results Temperature above the threshold of 43℃ was reached only when the power was>40 W and when there was adequate irrigation(at least 15–30 mL/min).Shorter lasing time divided by lithotripsy time or operator duty cycles less than 70%also resulted in a smaller temperature rise.Conclusion At least eight factors modify the thermal effects of lasers,and most importantly,the use of chilled irrigation at higher perfusion rates,lower power settings of<40 W,and with a shorter operator duty cycle will help to prevent thermal injuries from occurring.Stones impacted in the ureter or pelvi-ureteric junction further increase the probability of thermal injuries during laser firing. 展开更多
关键词 Stone disease Laser lithotripsy IRRIGATION Thermal effect Operator duty cycle
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Immunomodulatory effects and clinical application of exosomes derived from mesenchymal stem cells 被引量:1
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作者 Yang-Fei Yi Zi-Qi Fan +5 位作者 Can Liu Yi-Tong Ding Yao Chen Jie Wen Xiao-Hong Jian Yu-Fei Li 《World Journal of Stem Cells》 2025年第3期1-15,共15页
Exosomes(Exos)are extracellular vesicles secreted by cells and serve as crucial mediators of intercellular communication.They play a pivotal role in the pathogenesis and progression of various diseases and offer promi... Exosomes(Exos)are extracellular vesicles secreted by cells and serve as crucial mediators of intercellular communication.They play a pivotal role in the pathogenesis and progression of various diseases and offer promising avenues for therapeutic interventions.Exos derived from mesenchymal stem cells(MSCs)have significant immunomodulatory properties.They effectively regulate immune responses by modulating both innate and adaptive immunity.These Exos can inhibit excessive inflammatory responses and promote tissue repair.Moreover,they participate in antigen presentation,which is essential for activating immune responses.The cargo of these Exos,including ligands,proteins,and microRNAs,can suppress T cell activity or enhance the population of immunosuppressive cells to dampen the immune response.By inhibiting lymphocyte proliferation,acting on macrophages,and increasing the population of regulatory T cells,these Exos contribute to maintaining immune and metabolic homeostasis.Furthermore,they can activate immune-related signaling pathways or serve as vehicles to deliver microRNAs and other bioactive substances to target tumor cells,which holds potential for immunotherapy applications.Given the immense therapeutic potential of MSC-derived Exos,this review comprehensively explores their mechanisms of immune regulation and therapeutic applications in areas such as infection control,tumor suppression,and autoimmune disease management.This article aims to provide valuable insights into the mechanisms behind the actions of MSC-derived Exos,offering theoretical references for their future clinical utilization as cell-free drug preparations. 展开更多
关键词 Mesenchymal stem cells EXOSOMES Immunomodulatory effects Clinical application Therapeutic potential
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Late effects of the treatment of childhood cancer
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作者 Jelena Roganovic 《World Journal of Clinical Cases》 SCIE 2025年第7期6-12,共7页
Excellent progress has been made in the last few decades in the cure rates of pediatric malignancies,with more than 80%of children with cancer who have access to contemporary treatment being cured.However,the therapie... Excellent progress has been made in the last few decades in the cure rates of pediatric malignancies,with more than 80%of children with cancer who have access to contemporary treatment being cured.However,the therapies responsible for this survival can also produce adverse physical and psychological long-term outcomes,referred to as late effects,which appear months to years after the completion of cancer treatment.Research has shown that 60%to 90%of childhood cancer survivors(CCSs)develop one or more chronic health conditions,and 20%to 80%of survivors experience severe or life-threatening complications during adulthood.Therefore,understanding the late side effects of such treatments is important to improve the health and quality of life of the growing population of CCSs. 展开更多
关键词 SURVIVORSHIP CANCer CHILDREN TREATMENT Late effects
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基于非Fourier生物热传导解析解的激光辐照皮肤组织热损伤分析
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作者 张丽静 张齐 尚新春 《北京理工大学学报》 北大核心 2026年第2期192-201,共10页
较为准确地预测激光辐照下皮肤组织内部的热分布和热损伤是生物医学领域的一个难题.为探究这个问题,提出了一种使用Laplace和Hankel变换推导出解析解的策略.建立三维非Fourier热传导模型,并引入升温函数简化问题.通过积分变换及其逆变... 较为准确地预测激光辐照下皮肤组织内部的热分布和热损伤是生物医学领域的一个难题.为探究这个问题,提出了一种使用Laplace和Hankel变换推导出解析解的策略.建立三维非Fourier热传导模型,并引入升温函数简化问题.通过积分变换及其逆变换推导出解析解,并基于该解析解进行数值模拟,得到了不同辐照时间和半径下皮肤热分布和热损伤的预测结果,进而研究了激光辐照持续时间和半径对皮肤组织的影响.此外,对非Fourier热传导模型和经典Fourier热传导模型得到的皮肤组织热损伤预测结果进行了全面比较.分析结果表明,非Fourier和经典Fourier两种热传导模型所预测的热损伤深度是不同的.具体来讲,在短时间辐照时,非Fourier热传导理论的预测深度要小于Fourier热传导理论,而长时间辐照时,结果恰好相反. 展开更多
关键词 激光 生物材料 非Fourier效应 积分变换 解析解 热损伤
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Coupling of alloying and interface effects in dendritic Au-doped PtPd alloy/dumbbell-like bismuth telluride heterostructures for ethanol and methanol electrooxidation 被引量:1
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作者 Ting-Ting Zhou Kai-Yu Dong +1 位作者 Zhe Zheng Qiang Yuan 《Rare Metals》 2025年第5期3119-3129,共11页
Alloying and interface effects are effective strategies for enhancing the performance of electrocatalysts in energy-related devices.Herein,dendritic Au-doped platinum-palladium alloy/dumbbell-like bismuth telluride he... Alloying and interface effects are effective strategies for enhancing the performance of electrocatalysts in energy-related devices.Herein,dendritic Au-doped platinum-palladium alloy/dumbbell-like bismuth telluride heterostructures(denoted PtPdAu/BiTe)were synthesized using a visible-light-assisted strategy.The coupling alloy and interfacial effects of PtPdAu/BiTe significantly improved the performance and stability of both the ethanol oxidation reaction(EOR)and methanol oxidation reaction(MOR).Introducing a small amount of Au effectively enhanced the CO tolerance of PtPdAu/BiTe compared to dendritic platinum-palladium alloy/dumbbell-like bismuth telluride heterostructures.PtPdAu/BiTe exhibited mass activities of 31.5 and 13.3 A·mg_(Pt)^(-1)in EOR and MOR,respectively,which were 34.4 and 13.2 times higher than those of commercial Pt black,revealing efficient Pt atom utilization.In-situ Fourier transform infrared spectroscopy demonstrated complete 12e^(-)and 6e^(-)oxidation of ethanol and methanol on PtPdAu/BiTe.The PtPdAu/BiTe/C achieved mass peak power densities of 131 and 156 mW·mg_(Pt)^(-1),which were 2.4 and 2.2 times higher than those of Pt/C in practical direct ethanol fuel cell(DEFC)and direct methanol fuel cell(DMFC),respectively,highlighting their potential application in DEFC and DMFC.This study introduces an effective strategy for designing efficient and highly CO tolerant anodic electrocatalysts for practical DEFC and DMFC applications. 展开更多
关键词 PtPdAu Alloying and interface effects HETerOSTRUCTURE Methanol and ethanol oxidation Fuel cell
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A self-powered Ag/β-Ga_(2)O_(3) photodetector with broadband response from 200 to 980 nm based on the photovoltaic and pyro-phototronic effects 被引量:1
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作者 Xiongxin Luo Yueming Zhang +5 位作者 Lindong Liu Andy Berbille Kaixuan Wang Gaosi Han Laipan Zhu Zhong Lin Wang 《Journal of Materials Science & Technology》 2025年第3期125-134,共10页
β-Ga_(2)O_(3),as one of the important 4th generation semiconductors,is widely used in solar-blind ultraviolet(UV)detectors with a short detection range of 200-280 nm benefiting from its ultra-wide bandgap,strong radi... β-Ga_(2)O_(3),as one of the important 4th generation semiconductors,is widely used in solar-blind ultraviolet(UV)detectors with a short detection range of 200-280 nm benefiting from its ultra-wide bandgap,strong radiation resistance,and excellent chemical and thermal stabilities.Here,a self-powered photodetector(PD)based on an Ag/β-Ga_(2)O_(3) Schottky heterojunction was designed and fabricated.Through a subtle design of electrodes,the pyro-phototronic effect was discovered,which can be coupled to the common photovoltaic effect and further enhance the performance of the PD.Compared to traditional Ga_(2)O_(3)-based PD,the as-used PD exhibited a self-driving property and a broadband response beyond the bandgap lim-itations,ranging from 200 nm(deep UV)to 980 nm(infrared).Moreover,the photoresponse time was greatly shrunk owing to the coupling effect.Under laser irradiation,with a wavelength of 450 nm and a power density of 8 mW cm-2,the photocurrent could be improved by around 41 times compared with the sole photovoltaic effect.Besides,the performances of the Schottky PD were enhanced at both high and low temperatures.The device also possessed long-term working stability.This paper not only re-veals basic physics lying in the 4th generation semiconductor Ga_(2)O_(3) but also sheds light on the multi-encryption transmission of light information using this PD. 展开更多
关键词 PHOTODETECTOR β-Ga_(2)O_(3) Broadband response Pyro-phototronic effect SELF-POWerED
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Enhanced selectivity of catalytic hydrogenation of halogenated nitroaromatics by interfacial effects
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作者 HUANG Rui LIU Shengjie +1 位作者 WU Qingyuan ZHENG Nanfeng 《无机化学学报》 北大核心 2025年第1期201-212,共12页
The highly selective catalytic hydrogenation of halogenated nitroaromatics was achieved by employing Pd‑based catalysts that were co‑modified with organic and inorganic ligands.It was demonstrated that the catalysts c... The highly selective catalytic hydrogenation of halogenated nitroaromatics was achieved by employing Pd‑based catalysts that were co‑modified with organic and inorganic ligands.It was demonstrated that the catalysts contained Pd species in mixed valence states,with high valence Pd at the metal‑support interface and zero valence Pd at the metal surface.While the strong coordination of triphenylphosphine(PPh3)to Pd0 on the Pd surface prevents the adsorption of halogenated nitroaromatics and thus dehalogenation,the coordination of sodium metavanadate(NaVO3)to high‑valence Pd sites at the interface helps to activate H2 in a heterolytic pathway for the selective hydrogenation of nitro‑groups.The excellent catalytic performance of the interfacial active sites enables the selective hydrogenation of a wide range of halogenated nitroaromatics. 展开更多
关键词 halogenated nitroaromatic heterogeneous catalysis HYDROGENATION selectivity control interfacial effect
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Revealing effects of creep damage on high-temperature fatigue behavior for HfNbTiZr refractory high-entropy alloys:Experimental investigation and crystal-plasticity modelling 被引量:1
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作者 Long Xu Hui Chen +6 位作者 Yuefei Jia Dongpeng Wang Shiwei Wu Yandong Jia Gang Wang Zixu Guo Yilun Xu 《Journal of Materials Science & Technology》 2025年第28期134-150,共17页
Refractory high-entropy alloys(RHEAs)are promising for high-temperature applications due to their ex-ceptional mechanical properties at high temperatures.However,limited studies on their high-temperature fatigue behav... Refractory high-entropy alloys(RHEAs)are promising for high-temperature applications due to their ex-ceptional mechanical properties at high temperatures.However,limited studies on their high-temperature fatigue behavior hinder further development.This study systematically investigates the low-cycle fatigue(LCF)behavior of HfNbTiZr RHEA at room temperature(25℃)and elevated temperatures(350,450,and 600℃)through a combination of experimental analyses and dislocation-based damage-coupled crystal plasticity finite element(CPFE)simulations,to unveil the effects of creep damage on LCF behavior at varying temperatures.The results indicate that the LCF life dramatically decreases at an increased tem-perature,shifting from transgranular fatigue damage at lower temperatures(25-350℃)to a dual damage mechanism involving both intergranular fatigue and creep damage at higher temperatures(450-600℃).At 600℃,creep damage notably contributes to the accumulation of geometrically necessary dislocations(GNDs),crack initiation,and propagation at grain boundaries,and thus accelerates LCF failure.Compara-tive CPFE simulations reveal that creep damage significantly contributes to cyclic softening and reduction in elastic modulus,which also amplifies the strain localization under the LCF loading.The contribution of creep damage to the total stored energy density(SED)representing the overall damage increases with temperatures,accounting for 11%at 600℃.Additionally,CPFE simulations indicate that the creep dam-age notably influences the magnitude of GND density localized at grain boundaries.This study provides critical insights into the fatigue damage mechanisms of RHEAs,offering valuable guidance for their ap-plication in high temperatures. 展开更多
关键词 Refractory high-entropy alloys Elevated-temperature low-cycle fatigue Crystal plasticity finite element simulation Fatigue damage mechanisms Creep damage effect
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Synergistic effects of Er and Sc on aging behavior and θ′precipitation stability of Al−Cu alloys
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作者 Xing-kai HOU Sheng-ping WEN +6 位作者 Peng QI Wu WEI Xiao-lan WU Hui HUANG Kun-yuan GAO Xiang-yuan XIONG Zuo-ren NIE 《Transactions of Nonferrous Metals Society of China》 2025年第8期2435-2448,共14页
The effects of the synergistic addition of Er and Sc on the aging and interfacial segregation behaviors of alloys were systematically studied using transmission electron microscopy(TEM)and high-angle annular dark fiel... The effects of the synergistic addition of Er and Sc on the aging and interfacial segregation behaviors of alloys were systematically studied using transmission electron microscopy(TEM)and high-angle annular dark field(HAADF)imaging.The TEM results show that Al3(Sc,Zr)with a core-shell structure can act as nucleation particles forθ′to promote uniform and fine precipitation.The STEM results show that Er solute atoms were preferentially enriched inside theθ′precipitate during thermal exposure at 225℃for 150 h.However,Sc and Mn solute atoms segregated at theθ′/α-Al matrix interface were observed at 300℃.Due to the early enrichment of Er in theθ′precipitate,the slowly diffusing Sc and Mn were segregated to the interface of theθ′precipitate before the severe coarsening of theθ′precipitate,thus further stabilizing theθ′precipitate at higher temperatures. 展开更多
关键词 er−Sc co-addition aging behavior θ′precipitation stability solute segregation Al−Cu alloys
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Solid-state Effects on Luminescence Properties of TADF Emitters Based on Pyrido[2,3-b]pyrazine-Dihydrophenazasilines Donor-acceptor Structures:Theoretical Study
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作者 LI Yuheng LIU Meiqi +2 位作者 HOU Baoming PAN Yuyu YANG Bing 《发光学报》 北大核心 2025年第2期354-365,共12页
Thermally activated delayed fluorescence(TADF)molecules have outstanding potential for applications in organic light-emitting diodes(OLEDs).Due to the lack of systematic studies on the correlation between molecular st... Thermally activated delayed fluorescence(TADF)molecules have outstanding potential for applications in organic light-emitting diodes(OLEDs).Due to the lack of systematic studies on the correlation between molecular structure and luminescence properties,TADF molecules are far from meeting the needs of practical applications in terms of variety and number.In this paper,three twisted TADF molecules are studied and their photophysical properties are theoretically predicted based on the thermal vibrational correlation function method combined with multiscale calculations.The results show that all the molecules exhibit fast reverse intersystem crossing(RISC)rates(kRISC),predicting their TADF luminescence properties.In addition,the binding of DHPAzSi as the donor unit with different acceptors can change the dihedral angle between the ground and excited states,and the planarity of the acceptors is positively correlated with the reorganization energy,a property that has a strong influence on the non-radiative process.Furthermore,a decrease in the energy of the molecular charge transfer state and an increase in the kRISC were observed in the films.This study not only provides a reliable explanation for the observed experimental results,but also offers valuable insights that can guide the design of future TADF molecules. 展开更多
关键词 solid-state effects thermally activated delayed fluorescence(TADF) theoretical study multi-scale simulation
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S⁃anion effects on the improvement of adsorption capacity and performance for benzyl alcohol electro⁃oxidation catalysts
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作者 ZHANG Yufeng QI Haotian +5 位作者 ZHONG Jingya LANG Leiming YUAN Guojun LU Siqi WANG Haiying LIU Guangxiang 《无机化学学报》 北大核心 2025年第12期2591-2600,共10页
Ni_(2)CoS_(4)was prepared by the liquid‑phase method and applied to the benzyl alcohol electro‑oxidation reaction(BAOR),demonstrating excellent catalytic activity[with a current density of 271 mA·cm^(-2)at 1.40 V... Ni_(2)CoS_(4)was prepared by the liquid‑phase method and applied to the benzyl alcohol electro‑oxidation reaction(BAOR),demonstrating excellent catalytic activity[with a current density of 271 mA·cm^(-2)at 1.40 V(vs RHE)]and long‑term stability.The S‑anion effect can regulate the charge distribution on the catalyst surface,thereby enhancing the additional adsorption capacity of OH-at the Co sites.By combining material characterization and theoretical calculations,it can be observed that this process can increase the concentration of the OH^(*)intermediate,accelerate the activation process of the Ni site,and ultimately achieve an improvement in overall activity and stability. 展开更多
关键词 benzyl alcohol electrooxidation reaction Ni‑based catalyst anionic effect anode electrooxidation
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Thermal and Friction Effects on Mixed Mode Delamination
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作者 Abdellah Benchekkour Nazihe Terfaya +1 位作者 Mohammed Elmir Barhm Abdullah Mohamad 《Journal of Harbin Institute of Technology(New Series)》 2025年第3期75-81,共7页
A comprehensive numerical investigation into mixed⁃mode delamination is presented in this study.It aims to assess the impact of thermal and friction effects through mixed⁃mode flexure crack propagation testing.Finite ... A comprehensive numerical investigation into mixed⁃mode delamination is presented in this study.It aims to assess the impact of thermal and friction effects through mixed⁃mode flexure crack propagation testing.Finite element analysis was employed to model the delamination process,incorporating a contact cohesive zone model.This model couples the traction⁃separation law,the contact law,and the Coulomb friction law simultaneously.The thermomechanical analysis in this study is performed using a sequentially coupled approach,implemented with the finite element software ABAQUS.The findings underscore the importance of this study. 展开更多
关键词 DELAMINATION mixed mode thermal effect friction effect contact cohesive model
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Loading effects of unsaturated loess considering the influence of closed gas phase
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作者 Biao Qin Xi'an Li +2 位作者 Li Wang Hao Chai Qian Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第4期2416-2432,共17页
Loess is susceptible to loading effects such as significant changes in strength and volume variation caused by loading and wetting.In this study,considering the different connection states of pore water and gas in loe... Loess is susceptible to loading effects such as significant changes in strength and volume variation caused by loading and wetting.In this study,considering the different connection states of pore water and gas in loess fabric,the gas phase closure case is incorporated into a unified form of the generalized effective stress framework,introducing a damage parameter considering the effects of closed pore gas.The loading effects of unsaturated loess under wide variations in saturation are described in a unified way,and the model performance is verified by corresponding stress and hydraulic path tests.The results indicated that the collapse response involves the initial void ratio of loess,and the coupled outwards motion of the loading-collapse(LC)yield surface under loading enhances its structural strength.Suction-enhanced yield stress requires a greater"tensile stress"to counteract its structural stability.The nucleation of bubbles at high saturation causes a decrease in yield stress.The loading effect exhibits a smaller collapse behavior when the influence of closed gas is considered,whereas the suction path does not cross the LC in the stress space under hydraulic action for the same parameters,which amplifies the influence of closed gas on loess deformation. 展开更多
关键词 Unsaturated loess Closed gas Generalized effective stress Loading effect Constitutive model
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