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A review of nanodiamond-based photocatalysts for solar energy conversion
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作者 Zhang Wan Cheng Xiangxiang +5 位作者 Guo Kesheng Zhang Hansong Li Lanxiao Zhao Yongbing Zhu Jiaqi Wang Yongjie 《新型炭材料(中英文)》 北大核心 2026年第1期18-43,共26页
Photocatalysis is an important technology for using solar energy to produce hydrogen,convert CO_(2) to synthetic fuels,and decrease persistent pollutant.However,conventional photocatalysts have limitations,including p... Photocatalysis is an important technology for using solar energy to produce hydrogen,convert CO_(2) to synthetic fuels,and decrease persistent pollutant.However,conventional photocatalysts have limitations,including poor spectral absorption,inefficient charge separation,and structural instability under operational stress,which demand innovative durable materials with tailored electronic properties.Nanodiamond(ND)has recently been recognized as a suitable material because of its exceptional chemical stability,superior charge carrier mobility,and possible surface functionalization.While its intrinsic wide bandgap limits its response to visible-light,different methods have been demonstrated to activate its catalytic potential.Here,several emerging strategies for improving the catalytic performance of ND-based photocatalytic systems are summarized,including surface functionalization,plasmonic hybridization,heteroatom doping,and heterostructure design.And the structure-activity relationship and design principle are proposed to improve the light harvesting,charge transport,and redox kinetics for constructing high efficiency ND-based photocatalysts used in the renewable energy and environmental industries. 展开更多
关键词 PHOTOCATALYSIS NANOdIAMONd Solar fuel conversions FUNCTIONALIZATION dOPING HETEROSTRUCTURE
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Advances in electrocatalytic and photocatalytic CO_(2)conversion to value-added chemicals using copper-based covalent organic frameworks
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作者 LI Yue LIU Ziqi +7 位作者 FENG Ke LI Yingdan NING Yue SHEN Li LU Jitao MENG Qingguo WANG Min WANG Haiying 《无机化学学报》 北大核心 2026年第1期1-22,共22页
CO_(2)reduction technology can promote the resource utilization of carbon and help alleviate global warming and energy supply pressure.It is an effective way to achieve energy conversion and utilization.Covalent organ... CO_(2)reduction technology can promote the resource utilization of carbon and help alleviate global warming and energy supply pressure.It is an effective way to achieve energy conversion and utilization.Covalent organic frameworks(COFs)are porous crystalline materials formed by connecting organic monomers through covalent bonds.They have the characteristics of functional diversity and rich chemical properties.Their advantages,such as high porosity,a wide range of visible light absorption,and excellent charge separation efficiency,give them good potential in CO_(2)capture,separation,and conversion.Currently,Cu is a key metal in the catalytic CO_(2)reduction reaction(CO_(2)RR)for the preparation of high-value-added chemicals.The preparation of highly stable and large-pore Cu-based COFs using COFs as an ideal sacrificial template for loading Cu can be used to develop high-performance electrocatalysts and photocatalysts.In this review,we discuss the latest advancements in this field,including the development of various Cu-based COFs and their applications as catalysts for CO_(2)RR.Here,we mainly introduce the synthesis strategies,some important characterization information,and the applications of electrocatalytic and photocatalytic CO_(2)conversion using these previously reported Cu-based COFs. 展开更多
关键词 copper-based covalent organic frameworks CO_(2)reduction reactions electrocatalytic CO_(2)conversion photocatalytic CO_(2)conversion
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Hydrothermal conversion from hydrogarnet to hydroandradite based on alumina recovery from red mud
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作者 Hong-fei WU Xiao-lin PAN +3 位作者 Ji-long LIU Feng QIU Tun HE Hai-yan YU 《Transactions of Nonferrous Metals Society of China》 2026年第1期309-322,共14页
To synergistically recover alumina and alkali from red mud(RM),the structural stability and conversion mechanism of hydroandradite(HA)from hydrogarnet(HG)were investigated via the First-principles,XRF,XRD,PSD and SEM ... To synergistically recover alumina and alkali from red mud(RM),the structural stability and conversion mechanism of hydroandradite(HA)from hydrogarnet(HG)were investigated via the First-principles,XRF,XRD,PSD and SEM methods,and a novel hydrothermal process based on the conversion principle was finally proposed.The crystal structure simulation shows that the HA with varied silicon saturation coefficients is more stable than HG,and the HA with a high iron substitution coefficient is more difficult to be converted from HG.The(110)plane of Fe_(2)O_(3) is easier to combine with HG to form HA,and the binding energy is 81.93 kJ/mol.The effects of raw material ratio,solution concentration and hydrothermal parameters on the conversion from HG to HA were revealed,and the optimal conditions for the alumina recovery were obtained.The recovery efficiencies of alumina and Na_(2)O from the RM are 63.06%and 97.34%,respectively,and the Na_(2)O content in the treated RM is only 0.13%. 展开更多
关键词 HYdROGARNET hydroandradite structural stability hydrothermal conversion red mud
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Laser-induced graphene as a“materials toolbox”for energy storage,conversion and harvesting applications
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作者 Avinash Kothuru Fernando Patolsky 《Journal of Energy Chemistry》 2026年第2期408-443,I0010,共37页
Laser-induced graphene(LIG)has emerged as a versatile,sustainable material for advanced energy technologies,offering a scalable,catalyst-free,and programmable method to directly convert carbon-rich substrates into por... Laser-induced graphene(LIG)has emerged as a versatile,sustainable material for advanced energy technologies,offering a scalable,catalyst-free,and programmable method to directly convert carbon-rich substrates into porous,conductive graphene.This single-step laser writing approach enables flexible,patternable electrodes without complex post-processing.With its high conductivity,large surface area,and tunable chemistry,LIG is well-suited for diverse applications including batteries,supercapacitors,dyesensitized solar cells(DSSCs),dual cells,water-splitting electrocatalysis,and triboelectric nanogenerators(TENGs).In energy storage,LIG improves charge transport,buffer volume changes,and provides a robust framework,enhancing capacitance,cycling stability,and rate capability.Its catalytic activity is further boosted through heteroatom doping or transition-metal incorporation,achieving HER/OER performance comparable to noble metals.In DSSCs,LIG functions as a flexible,low-cost alternative to platinum counter electrodes,while in TENGs,its strong triboelectric response and mechanical durability enable integration into self-powered,wearable systems.Despite the immense recent progress in this field,challenges remain regarding the scalability,long-term operational stability,and interfacial engineering of LIGbased composites.Further exploration into multi-laser systems,substrate diversity,and synergistic composite architectures will be crucial to optimizing device performance and reliability.Nevertheless,the green,cost-efficient,rapid,and programmable synthesis of LIG poses it as a cornerstone potential building block material in the development of future sustainable and multifunctional energy systems.Throughout the review we compare fabrication strategies,summarize performance metrics against relevant benchmarks,and identifying common mechanistic advantages conferred by the laser writing process.Remaining challenges-such as scale-up,precursor diversity,long-term environmental stability,and integration into complex device architectures-are outlined alongside prospective research directions.Collectively,this review article provides an in-depth perspective on the multifunctional nature of LIG,underscoring its promise in next-generation energy storage,conversion,harvesting applications,and laying the groundwork for future research directions. 展开更多
关键词 Laser-induced graphene Energy storage and conversion Battery SUPERCAPACITORS NANOGENERATORS ELECTROCATALYSIS
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Bio-inspired amino acid promoted nanofluidic ion transport and energy conversion in free-standing layered vermiculite-based membranes
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作者 Ruohan Feng Chaoran Zhang +1 位作者 Di Zhang Fang Song 《Green Energy & Environment》 2026年第1期248-257,共10页
Two-dimensional nanofluidic membranes have garnered considerable interest due to their potential for cost-effective osmotic energy harvesting.One promising approach to enhancing ion conductivity and selectivity is the... Two-dimensional nanofluidic membranes have garnered considerable interest due to their potential for cost-effective osmotic energy harvesting.One promising approach to enhancing ion conductivity and selectivity is the incorporation of vip additives.However,the traditional host-vip configuration can undermine the structural integrity of nanochannels owing to the inconsistent size and shape of these additives.Drawing inspiration from the intricate design of biological protein channels,which utilize small amino acid molecules as vips,we have addressed this issue by incorporating glycine,a common amino acid,into a vermiculite membrane using a simple vacuum-assisted infiltration method.The resulting vermiculite-glycine membrane demonstrates 1.8 times greater ionic conductivity and twice the power density compared to pure vermiculite membranes.Analysis based on glycine content,coupled with spectroscopic examination,reveals that ion conductivity is linked to the distribution of glycine molecules across three specific sites within the membrane.This suggests that glycine molecules—whether confined in voids,adsorbed onto nanochannel surfaces,or intercalated within multilayered vermiculite nanoparticles—enhance nanofluidic ion transport by modulating surface and space charge density,as well as strengthening hydrogen bonding,electrostatic interactions,and steric effects.This work reveals the specific interactions between amino acids and vermiculite,offering a novel path for advancing nanofluidic composite membranes and highlighting critical considerations for the proposed strategy. 展开更多
关键词 Amino acid Nanofluidics Ion transport Osmotic energy conversion Vermiculite-based membrane
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Design and experimental validation of a low-impact wing locking/release mechanism based on energy conversion strategy
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作者 Yanbing Wang Honghao Yue +5 位作者 Jun Wu Xueting Pan Fei Yang Yong Zhao Jicheng Liu Xue Bai 《Defence Technology(防务技术)》 2026年第1期241-256,共16页
Conventional locking/release mechanisms often face challenges in aircraft wing separation processes,such as excessive impact loads and insufficient synchronization.These may cause structural damage to the airframe or ... Conventional locking/release mechanisms often face challenges in aircraft wing separation processes,such as excessive impact loads and insufficient synchronization.These may cause structural damage to the airframe or attitude instability,seriously compromising mission reliability.To address this engineering challenge,this paper proposes a multi-point low-impact locking/release mechanism based on the mobility model and energy conversion strategy.Through establishing a DOF constraint framework system,this paper systematically analyzes the energy transfer and conversion characteristics during the wing separation process,reveals the generation mechanism of impact loads,and conducts research on low-impact design based on energy conversion strategy.Building on this foundation,a single-point locking/release mechanism employing parallel trapezoidal key shaft structure was designed,which increases frictional contact time and reduces the energy release rate,thereby achieving low-impact characteristics.The mechanism's performance was validated through physical prototype development and systematic functional testing(including unlocking force,synchronization,and impact tests).Experimental results demonstrate:(1)Under 14 kN preload condition,the maximum unlocking force was only 92.54 N,showing a linear relationship with preload that satisfies the"strong-connection/weak-unlock"design requirement;(2)Wing separation was completed within 46 ms,with synchronization time difference among three separation mechanisms stably controlled within 12-14 ms,proving rapid and reliable operation;(3)The unlocking impact acceleration ranged between 26 and 73 g,below the 100 g design limit,confirming the effectiveness of the energy conversion strategy.The proposed low-impact locking/release mechanism design method based on energy conversion strategy resolves the traditional challenges of high impact and synchronization deficiencies.The synergistic optimization mechanism of"structural load reduction and performance improvement"provides a highly reliable technical solution for wing separable mechanisms while offering novel design insights for wing connection/separation systems engineering. 展开更多
关键词 Hypersonic vehicle Energy conversion strategy Low-impact Wing separation Locking/release mechanism
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Mechanical Analysis of Free-Standing Cold-Water Pipe for Ocean Thermal Energy Conversion
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作者 Jing Li Bo Ning +3 位作者 Bo Li Xuemei Jin Dezhi Qiu Fenlan Ou 《Fluid Dynamics & Materials Processing》 2026年第1期86-100,共15页
As a controllable power generation method requiring no energy storage,Ocean Thermal Energy Conversion(OTEC)technology demonstrates characteristics of abundant reserves,low pollution,and round-the-clock stable operatio... As a controllable power generation method requiring no energy storage,Ocean Thermal Energy Conversion(OTEC)technology demonstrates characteristics of abundant reserves,low pollution,and round-the-clock stable operation.The free-standing cold-water pipe(CWP)in the system withstands various complex loads during operation,posing potential failure risks.To reveal the deformation and stress mechanisms of OTEC CWPs,this study first analyzes wave particle velocity and acceleration to determine wave loads at different water depths.Based on the Euler-Bernoulli beam model,a quasi-static load calculation model for OTEC CWPs was established.The governing equations were discretized using the finite difference method,and matrix equations were solved to analyze bending deformation,bending moments,and surface stresses at discrete points along the pipe.Results indicate that water depths within 50 m represent a critical zone where wave particle velocity,acceleration,and wave loads exhibit significant variations in harmonic patterns,while beyond 50 m depth wave loads decrease linearly.Ocean currents and surface wind-driven currents substantially influence the CWP’s lateral displacement.Considering the effect of clump weights,the maximum lateral displacement occurs at 600–800 m below sea level.Utilizing large-wall-thickness high-strength pipes at the top section significantly enhances the structural safety of the CWP system. 展开更多
关键词 Ocean thermal energy conversion wave load free standing pipe force analysis lateral displacement
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Adult central nervous regeneration in Drosophila:Evidence for glial lineage conversion and neurogenic potential post-injury
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作者 Sergio Casas-Tintó Maria Losada-Pérez 《Neural Regeneration Research》 2026年第7期2948-2949,共2页
Adult neurogenesis is generally considered to be very limited;however,there is increasing evidence that this phenomenon is conserved across species.Traditionally,research has focused on identifying precursor cells,tho... Adult neurogenesis is generally considered to be very limited;however,there is increasing evidence that this phenomenon is conserved across species.Traditionally,research has focused on identifying precursor cells,those that are actively dividing or have the potential to divide.Direct evidence of adult neurogenesis has been found in rats,mice,songbirds,and nonhuman primates.In humans,while the evidence is indirect,it strongly suggests that neurogenesis also occurs during adulthood.In mammals,this active neurogenesis is preserved by radial glial progenitors,which remain in specific niches in the subventricular zone of the lateral ventricles and in the subgranular zone of the hippocampal dentate gyrus(Kumar et al.,2019). 展开更多
关键词 adult neurogenesis subventricular zone neurogenic potential glial lineage conversion radial glial progenitors hippocampal dentate gyrus
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Asymmetric coupling of atop-type and hollow-type adsorbed ^(*)CO to boost electrocatalytic CO_(2)-to-C_(2) conversion on high-index Cu_(2)O crystal planes
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作者 Wei Peng Yao Shen +6 位作者 Xiaolin Yu Chenghang Zheng Xiao Zhang Jingkai Zhao Jiexu Ye Shihan Zhang Xiang Gao 《Chinese Chemical Letters》 2026年第1期577-583,共7页
Cuprous oxide(Cu_(2)O) is one of the most promising catalysts for electrochemical conversion of CO_(2) into value-added C_(2) products.The efficiency of CO_(2)-to-C_(2) conversion is highly dependent on the Cu_(2)O cr... Cuprous oxide(Cu_(2)O) is one of the most promising catalysts for electrochemical conversion of CO_(2) into value-added C_(2) products.The efficiency of CO_(2)-to-C_(2) conversion is highly dependent on the Cu_(2)O crystal plane orientation and the corresponding adsorbed ^(*)CO species.Herein,we constructed high-index crystal planes(311) in Cu_(2)O(CO-Cu_(2)O) via a facile self-selective CO-induced strategy under a CO atmosphere,which was verified by high-resolution transmission electron microscopy(HR-TEM) and atomic force microscopy(AFM) results.By exploiting the high surface energy of the high index crystal planes,^(*)CO species are stabilized in CO-Cu_(2)O during CO_(2)RR,resulting in exceptional catalytic performance for CO_(2)-to-C_(2)products.In situ infrared spectroscopy revealed that both atop-type(^(*)CO_(atop)) and hollow-type(^(*)CO_(hollow)) adsorption of ^(*)CO species occurred on the CO-Cu_(2)O.The asymmetric C-C coupling energy barrier between ^(*)CO_(atop) and ^(*)CO_(hollow) in(311) crystal plane decreases by 47.8 % compared to the symmetric coupling of ^(*)CO_(atop) in conventional(100) crystal planes.Consequently,the Faradaic efficiency of C_(2) products generated with CO-Cu_(2)O was increased by as high as 100 % compared to that with pristine Cu_(2)O. 展开更多
关键词 Electrocatalytic conversion Adsorbed^(*)CO Asymmetric C-C coupling Self-selective CO-induced strategy Cu_(2)O-based catalysts
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Mechanistic insights into methanol conversion and methanol-mediated tandem catalysis toward hydrocarbons
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作者 Jiahui He Guo Tian +5 位作者 Duohua Liao Zonglong Li Yu Cui Fei Wei Chunyang Zeng Chenxi Zhang 《Journal of Energy Chemistry》 2026年第1期778-803,I0017,共27页
Methanol,a crucial C1 intermediate,bridges traditional fossil-based chemical processes with emerging sustainable catalytic technologies by serving as both a versatile hydrogenation product from CO/CO_(2)and an active ... Methanol,a crucial C1 intermediate,bridges traditional fossil-based chemical processes with emerging sustainable catalytic technologies by serving as both a versatile hydrogenation product from CO/CO_(2)and an active intermediate for hydrocarbon synthesis.Despite significant progress in methanol-to-hydrocarbon(MTH)conversion,a comprehensive understanding of reaction mechanisms remains essential to enhance catalyst design and industrial applicability.This review critically synthesizes recent advances in mechanistic insights related to methanol conversion and methanol-mediated catalytic processes.Firstly,we systematically outline key reaction pathways involved in initial carbon–carbon(C–C)bond formation through direct and indirect mechanisms,emphasizing significant breakthroughs from spectroscopic analyses and theoretical calculations.Subsequently,we highlight the autocatalytic characteristics and dual-cycle mechanisms underlying MTH processes,critically evaluating the roles of zeolite structures,pore sizes,topology,and acidity in governing product selectivity and catalyst stability.Additionally,we discuss cutting-edge developments in tandem catalytic systems employing methanol as a pivotal intermediate for CO_(x)hydrogenation,emphasizing the transferable mechanistic principles and catalytic insights.Finally,we identify future research directions,including elucidating precise hydrocarbon pool(HCP)intermediates,optimizing zeolite structures through computational-guided design,and developing robust catalytic systems leveraging advanced characterization methods and artificial intelligence.By integrating multidisciplinary approaches from catalytic science,materials engineering,and reaction engineering,this review provides actionable guidance towards rational design and optimization of advanced catalytic systems for efficient methanol conversion processes. 展开更多
关键词 Methanol conversion Methanol-mediated processes Reaction mechanisms CO/CO_(2)hydrogenation Acidic zeolite
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Advancements and Innovations in Low-Temperature Hydrogen Electrochemical Conversion Devices Driven by 3D Printing Technology
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作者 Min Wang Xiuyue Wang +6 位作者 Enyang Sun Zhenye Kang Fan Gong Bin Hou Gaoqiang Yang Mingbo Wu Feng‑Yuan Zhang 《Nano-Micro Letters》 2026年第2期599-630,共32页
3D printing,as a versatile additive manufacturing technique,offers high design flexibility,rapid prototyping,minimal material waste,and the capability to fabricate complex,customized geometries.These attributes make i... 3D printing,as a versatile additive manufacturing technique,offers high design flexibility,rapid prototyping,minimal material waste,and the capability to fabricate complex,customized geometries.These attributes make it particularly well-suited for low-temperature hydrogen electrochemical conversion devices—specifically,proton exchange membrane fuel cells,proton exchange membrane electrolyzer cells,anion exchange membrane electrolyzer cells,and alkaline electrolyzers—which demand finely structured components such as catalyst layers,gas diffusion layers,electrodes,porous transport layers,and bipolar plates.This review provides a focused and critical summary of the current progress in applying 3D printing technologies to these key components.It begins with a concise introduction to the principles and classifications of mainstream 3D printing methods relevant to the hydrogen energy sector and proceeds to analyze their specific applications and performance impacts across different device architectures.Finally,the review identifies existing technical challenges and outlines future research directions to accelerate the integration of 3D printing in nextgeneration low-temperature hydrogen energy systems. 展开更多
关键词 3d printing HYdROGEN Proton exchange membrane fuel cells Water electrolyzers
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Trauma and Shame in Conversations with Friends
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作者 ZHANG Qian-nan 《Journal of Literature and Art Studies》 2025年第5期398-403,共6页
Sally Rooney,a young Irish writer,has been dubbed“the first great novelist of the millennial generation”.Conversations with Friends,her first work,demonstrates amazing insight and subtle expression as she explores a... Sally Rooney,a young Irish writer,has been dubbed“the first great novelist of the millennial generation”.Conversations with Friends,her first work,demonstrates amazing insight and subtle expression as she explores a wide range of realistic issues such as modern intimacy,class injustice,and politics,all while depicting the complex interaction between two college girls and a celebrity couple from Dublin.This paper will use psychoanalytic viewpoints from scholars such as Freud,Garland,and Kaufman to examine the trauma and shame experienced by the heroine Frances,as well as the possibilities and ways in which adults can heal the trauma.Rooney completes the trauma narrative of modern people by portraying the life and feelings of Frances,a normal modern youth. 展开更多
关键词 Sally Rooney conversations with Friends TRAUMA SHAME
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Understanding users’effective use of generative conversational AI from a media naturalness perspective:a hybrid structural equation modeling-artificial neural network(SEM-ANN)approach
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作者 Kun Wang Yaobin Lu Zhao Pan 《Data Science and Management》 2025年第2期147-159,共13页
Although generative conversational artificial intelligence(AI)can answer questions well and hold conversations as a person,the semantic ambiguity inherent in text-based communication poses challenges to effective use.... Although generative conversational artificial intelligence(AI)can answer questions well and hold conversations as a person,the semantic ambiguity inherent in text-based communication poses challenges to effective use.Effective use reflects the users’utilization of generative conversational AI to achieve their goals,which has not been previously studied.Drawing on the media naturalness theory,we examined how generative conversational AI’s content and style naturalness affect effective use.A two-wave survey was conducted to collect data from 565 users of generative conversational AI.Two techniques were used in this study.Initially,partial least squares structural equation modeling(PLS-SEM)was applied to determine the variables that significantly affected the mechanisms(i.e.,cognitive effort and communication ambiguity)and effective use.Secondly,an artificial neural network model was used to evaluate the relative importance of the significant predictors of mechanisms and effective use identified from the PLS-SEM analysis.The results revealed that the naturalness of content and style differed in their effects on cognitive effort and communication ambiguity.Additionally,cognitive effort and communication ambiguity negatively affected effective use.This study advances the literature on effective use by uncovering the psychological mechanisms underlying effective use and their antecedents.In addition,this study offers insights into the design of generative conversational AI. 展开更多
关键词 Generative conversational AI Content naturalness Style naturalness Effective use SEM-ANN method
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A Study of Discourse Markers in Foreign Language Classrooms from the Perspective of Conversation Analysis
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作者 Shurui Ren Yanying Cui 《Journal of Contemporary Educational Research》 2025年第9期86-91,共6页
Based on conversation analysis theory,this study explored how teachers and students used discourse markers in foreign language classrooms and how these markers affect classroom interaction.The results showed that teac... Based on conversation analysis theory,this study explored how teachers and students used discourse markers in foreign language classrooms and how these markers affect classroom interaction.The results showed that teachers use different discourse markers in different teaching stages such as lead-in,presentation,practice and summary to make their teaching more organized and clearer.However,students used these markers less often,and their expressions are often less coherent.Based on these findings,the study suggests teaching strategies for teachers and learning strategies for students to improve how they use discourse markers.This can help make foreign language teaching more effective and interactive. 展开更多
关键词 conversation analysis discourse markers Foreign language teaching Teaching strategies Teacher-student interaction
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Leveraging We-Media for Enhancing English Conversational Skills
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作者 CHEN Yangtao 《Sino-US English Teaching》 2025年第7期217-221,共5页
In the context of globalization and digitalization,English has emerged as the primary language for international communication,making fluent conversational English skills essential for personal and professional growth... In the context of globalization and digitalization,English has emerged as the primary language for international communication,making fluent conversational English skills essential for personal and professional growth.The advent of We-Media,encompassing various online platforms,such as social media,blogs,and video content,has revolutionized the way English learners acquire and practice conversational skills.This paper explores the effective utilization of We-Media to enhance English conversational abilities,proposing practical strategies for both learners and educators.By integrating theories,such as second language acquisition,communicative language teaching,and media richness theory,the study highlights the strengths and challenges of We-Media in English learning.Through case studies and empirical analysis,the paper demonstrates the positive impact of We-Media on learners’speaking skills,emphasizing the importance of self-management,goal-setting,and consistent practice.The findings suggest that We-Media offers a flexible and diverse learning environment,but its effectiveness depends on learners’ability to self-regulate and employ effective learning strategies.The paper concludes with recommendations for future research and practical suggestions for educators and learners to maximize the benefits of We-Media in English education. 展开更多
关键词 We-Media English conversational skills second language acquisition communicative language teaching media richness theory self-directed learning online learning platforms language learning strategies
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高剂量维生素D在儿童短肠综合征合并维生素D不足/缺乏中的应用
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作者 吴青青 曹毅 +4 位作者 陆丽娜 陶怡菁 冯海霞 颜伟慧 王莹 《上海交通大学学报(医学版)》 北大核心 2026年第1期54-59,共6页
目的·探讨单次高剂量肌内注射途径补充维生素D对儿童短肠综合征(short bowel syndrome,SBS)合并维生素D不足/缺乏的安全性和有效性。方法·回顾性纳入32例SBS合并维生素D不足/缺乏的儿童。当患儿血清25-羟维生素D[25-hydroxyvi... 目的·探讨单次高剂量肌内注射途径补充维生素D对儿童短肠综合征(short bowel syndrome,SBS)合并维生素D不足/缺乏的安全性和有效性。方法·回顾性纳入32例SBS合并维生素D不足/缺乏的儿童。当患儿血清25-羟维生素D[25-hydroxyvitamin D,25-(OH)D]浓度低于50 nmol/L时,通过肌内注射途径补充200000 IU的维生素D2。收集患儿的临床资料(性别、年龄、原发疾病、小肠剩余长度、是否保留回盲瓣以及结肠是否完整等),记录肌内注射部位皮肤情况,以及维生素D补充前和补充后1个月的血清25-(OH)D、钙、磷和碱性磷酸酶水平状况。结果·SBS患儿入组时的中位年龄为5.0(3.0,7.0)个月。小肠闭锁和坏死性小肠结肠炎是导致SBS的主要原因(分别占28.13%和21.88%),剩余小肠平均长度为(57.27±24.55)cm。在补充维生素D之前,65.63%(21/32)的患儿存在维生素D缺乏,34.38%(11/32)的患儿存在维生素D不足。在补充维生素D之后,患儿25-(OH)D水平由28.87 nmol/L显著升高至53.10 nmol/L(P<0.001);在维生素D不足的患儿中,25-(OH)D水平从37.30 nmol/L显著升高至58.51 nmol/L(P=0.010);而在维生素D缺乏的患儿中,该水平从26.91 nmol/L显著升高至44.82 nmol/L(P<0.001);62.50%(20/32)的患儿25-(OH)D浓度达到正常水平。所有患儿在研究期间均未出现维生素D中毒、高钙血症、皮肤硬结或局部感染等并发症。结论·单次、高剂量(200000 IU)肌内注射途径补充维生素D,可以安全、有效地改善SBS合并维生素D不足/缺乏婴儿的维生素D水平。 展开更多
关键词 短肠综合征 儿童 高剂量 维生素d
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基于金属纳米光栅结构修饰的D型光纤表面等离激元共振超材料传感器研究
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作者 刘琨 熊艺扬 +8 位作者 井建迎 朱枫彤 肖璐 战晓寒 刘津畅 江俊峰 徐天华 王双 刘铁根 《量子电子学报》 北大核心 2026年第1期141-150,共10页
超材料因其独特的亚波长结构设计和独特的电磁响应特性,在提升表面等离激元共振(Surface Plasmon Resonance,SPR)传感器灵敏度方面具有广阔前景。本文设计了一款金属纳米光栅结构修饰的D型光纤SPR超材料传感器,并对折射率范围在1.332~1.... 超材料因其独特的亚波长结构设计和独特的电磁响应特性,在提升表面等离激元共振(Surface Plasmon Resonance,SPR)传感器灵敏度方面具有广阔前景。本文设计了一款金属纳米光栅结构修饰的D型光纤SPR超材料传感器,并对折射率范围在1.332~1.344的低折射率溶液进行了传感检测。首先,基于倏逝波和表面等离极化激元(Surface Plasmon Polaritons,SPPs)的光波矢特性,对D型光纤SPR传感器进行了理论分析,绘制得到不同折射率下共振波长随入射角度变化的解析解曲线,以便研究光纤中不同传导模式下的SPR激发条件。进而建立了D型光纤SPR超材料传感器二维有限元仿真模型进行模式分析研究,计算了模式损耗和传感器的灵敏度。最后,基于前述的仿真模型,具体构建了分别为以不同间隔的双条带或者单条带为金属光栅单元的传感器,以及使用银/铜替代金,作为金属连续层和金属光栅材料时的传感器,对比探究了这些传感器的灵敏度性能。研究结果表明,改变双条带光栅单元的条带间隔,对灵敏度的影响并不显著,与光栅单元为单条带的传感器灵敏度几乎一致;使用银替代金作为连续金属层材料时,传感器的灵敏度性能达到最优,可达1800 nm·RIU^(-1)。 展开更多
关键词 表面等离激元共振 灵敏度优化 金属纳米光栅 d型光纤
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拉萨市不同孕期妇女血清25羟基维生素D水平的比较
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作者 尼玛顿珠 扎西央宗 +5 位作者 边珍 益西措姆 支张卓玛 詹明君 巴桑央吉 秦绪珍 《基础医学与临床》 2026年第1期120-123,共4页
目的了解西藏拉萨市不同孕期妇女血清25羟基维生素D[25-(OH)D]浓度水平,观察不同孕期妇女维生素D(VD)营养状态。方法选取在2021年7月至2023年4月在西藏自治区人民医院产科门诊就诊的健康孕妇367例为研究对象,取同期209例未妊娠的育龄期... 目的了解西藏拉萨市不同孕期妇女血清25羟基维生素D[25-(OH)D]浓度水平,观察不同孕期妇女维生素D(VD)营养状态。方法选取在2021年7月至2023年4月在西藏自治区人民医院产科门诊就诊的健康孕妇367例为研究对象,取同期209例未妊娠的育龄期体检妇女为正常对照组,采用雅培i2000化学发光仪检测血清25-(OH)D水平,用SPSS统计学软件进行统计分析。结果367例孕期妇女血清25-(OH)D总体水平为11.5(8.5,17.3)ng/mL。VD充足、不足、缺乏分别占16.6%、30.0%、53.4%;209例健康对照组妇女血清25-(OH)D总体水平为9.9(7.7,13.6)ng/mL。VD充足、不足、缺乏分别占6.7%、27.8%、65.5%。9~13^(+6)周、15~20^(+6)周孕期妇女血清25-(OH)D水平比较差异无统计学意义。结论拉萨市孕期和未妊娠育龄妇女普遍存在VD不足或缺乏现象,应在备孕及怀孕期间补充VD。 展开更多
关键词 孕妇 25羟基维生素d 维生素d
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甲型流感病毒感染相关危险因素及其25-羟基维生素D与血常规参数表达
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作者 于丽瑞 黄玉焕 周曼丽 《病毒学报》 北大核心 2026年第1期200-206,共7页
目的分析甲型流感病毒(INFA)感染相关危险因素及其25-羟基维生素D[25(OH)D]与血常规参数表达特点。方法选取我院2022年10月-2024年9月收治的212例有流感症状患儿,根据上呼吸道核酸六项检测结果分为INFA感染组(n=55)和INFA未感染组(n=15... 目的分析甲型流感病毒(INFA)感染相关危险因素及其25-羟基维生素D[25(OH)D]与血常规参数表达特点。方法选取我院2022年10月-2024年9月收治的212例有流感症状患儿,根据上呼吸道核酸六项检测结果分为INFA感染组(n=55)和INFA未感染组(n=157),采用Logistic回归模型分析INFA感染相关危险因素,采用ROC曲线分析预测变量准确性。结果212例患儿中,INFA感染55例(25.94%)。多因素结果显示:年龄、热程、咳嗽咳痰、喘息、未接种流感疫苗、住院时间是INFA感染的独立影响因素(P<0.05)。策树模型显示住院时间(≥7d)是重要预测因子。ROC分析结果显示:PLT、WBC、LYMPH、NEUT、MON、25(OH)D、HCT、MCV、Hb、CRP、SAA指标预测PICU中INFA感染均具有统计学意义(P<0.05)。结论PICU中INFA感染患儿早期具显著临床特征,应高度关注年龄、热程、咳嗽咳痰、喘息、未接种流感疫苗、住院时间等因素,加强血清25(OH)D及血常规水平监测,以预防INFA感染发生。 展开更多
关键词 甲型流感病毒感染 危险因素 25-羟基维生素d 血常规
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