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Chemical exchange saturation transfer MRI for neurodegenerative diseases:An update on clinical and preclinical studies
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作者 Ahelijiang Saiyisan Shihao Zeng +4 位作者 Huabin Zhang Ziyan Wang Jiawen Wang Pei Cai Jianpan Huang 《Neural Regeneration Research》 2026年第2期553-568,共16页
Chemical exchange saturation transfer magnetic resonance imaging is an advanced imaging technique that enables the detection of compounds at low concentrations with high sensitivity and spatial resolution and has been... Chemical exchange saturation transfer magnetic resonance imaging is an advanced imaging technique that enables the detection of compounds at low concentrations with high sensitivity and spatial resolution and has been extensively studied for diagnosing malignancy and stroke.In recent years,the emerging exploration of chemical exchange saturation transfer magnetic resonance imaging for detecting pathological changes in neurodegenerative diseases has opened up new possibilities for early detection and repetitive scans without ionizing radiation.This review serves as an overview of chemical exchange saturation transfer magnetic resonance imaging with detailed information on contrast mechanisms and processing methods and summarizes recent developments in both clinical and preclinical studies of chemical exchange saturation transfer magnetic resonance imaging for Alzheimer’s disease,Parkinson’s disease,multiple sclerosis,and Huntington’s disease.A comprehensive literature search was conducted using databases such as PubMed and Google Scholar,focusing on peer-reviewed articles from the past 15 years relevant to clinical and preclinical applications.The findings suggest that chemical exchange saturation transfer magnetic resonance imaging has the potential to detect molecular changes and altered metabolism,which may aid in early diagnosis and assessment of the severity of neurodegenerative diseases.Although promising results have been observed in selected clinical and preclinical trials,further validations are needed to evaluate their clinical value.When combined with other imaging modalities and advanced analytical methods,chemical exchange saturation transfer magnetic resonance imaging shows potential as an in vivo biomarker,enhancing the understanding of neuropathological mechanisms in neurodegenerative diseases. 展开更多
关键词 Alzheimer’s disease chemical exchange saturation transfer Huntington’s disease magnetic resonance imaging molecular imaging multiple sclerosis neurodegenerative disease Parkinson’s disease
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A Review on High-Efficiency Transfer of Graphene Films Free from Defects and Contamination
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作者 Wenhao Yin Chong Liu Jingmin Li 《Energy & Environmental Materials》 2025年第4期227-242,共16页
Graphene,owing to its exceptional electronic,optical,thermal,and mechanical properties,has emerged as a highly promising material.Currently,the synthesis of large-area graphene films on metal substrates via chemical v... Graphene,owing to its exceptional electronic,optical,thermal,and mechanical properties,has emerged as a highly promising material.Currently,the synthesis of large-area graphene films on metal substrates via chemical vapor deposition remains the predominant approach for producing high-quality graphene.To realize the potential applications of graphene,it is essential to transfer graphene films to target substrates in a manner that is non-destructive,clean,and efficient,as this significantly affects the performance of graphene devices.This review examines the current methods for graphene transfer from three perspectives:non-destructive transfer,clean transfer,and high-efficiency transfer.It analyzes and compares the advancements and limitations of various transfer techniques.Finally,the review identifies the key challenges faced by current graphene transfer methods and anticipates future developmental prospects. 展开更多
关键词 clean transfer defect-free transfer high-efficiency transfer of graphene
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5’-transfer RNA halve-lysine-CTT as a promising biomarker for early detection of hepatocellular carcinoma
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作者 Jie Yuan Wen-Chao Gu +5 位作者 Tian-Xin Xu Xian-Juan Shen Xian Li Lei Shen Yan Zhang Shao-Qing Ju 《World Journal of Gastrointestinal Oncology》 2025年第11期232-253,共22页
BACKGROUND Hepatocellular carcinoma(HCC)is a globally prevalent malignancy associated with high morbidity and mortality.Transfer RNA(tRNA)-derived small RNAs(tsRNAs),a class of small non-coding RNAs originating from t... BACKGROUND Hepatocellular carcinoma(HCC)is a globally prevalent malignancy associated with high morbidity and mortality.Transfer RNA(tRNA)-derived small RNAs(tsRNAs),a class of small non-coding RNAs originating from tRNA,have emerged as potential therapeutic targets in cancers,including HCC.However,the specific tsRNAs involved in HCC and their precise mechanisms remain largely unknown.In this study,we identify and characterize specific tsRNAs involved in the development and progression of HCC,discovering their potential as novel biomarkers for early detection and potential therapeutic targets.AIM To investigate differentially expressed tsRNAs in HCC,identify potential biomarkers,and elucidate the functions and mechanisms of tsRNAs in HCC.METHODS Differentially expressed tsRNAs in Barcelona Clinic Liver Cancer 0/A-stage HCC tissues were identified through high-throughput sequencing.Agarose gel electrophoresis,Sanger sequencing,and quantitative polymerase chain reaction were conducted to detect 5’-tRNA halve(tiRNA)-lysine(Lys)-CTT in tissues and serum samples.The diagnostic performance of 5’-tiRNA-Lys-CTT was evaluated using receiver operating characteristic analysis.HCC cell proliferation was examined using the Cell Counting Kit-8 assay,colony formation assay,and 5-ethynyl-2’-deoxyuridine staining.Additionally,the migratory capability of HCC cells was investigated using Transwell assays.RESULTS The 5’-tiRNA-Lys-CTT demonstrated excellent stability and can be easily detected.Its expression was significantly upregulated in 50 HCC tissues,110 HCC serum samples,and 5 HCC cell lines vs control groups,and the differences were all significant.This elevated expression was strongly associated with clinicopathological characteristics,particularly tumor size,Barcelona Clinic Liver Cancer stage,and cirrhosis of the liver.Receiver operating characteristic analysis revealed superior detection efficiency of 5’-tiRNA-Lys-CTT exhibits for early-stage HCC compared to established markers.Functional assays revealed that 5’-tiRNA-Lys-CTT overexpression promoted cell proliferation and migration,while its inhibition had the opposite effect.Bioinformatics predictions suggest that 5’-tiRNA-Lys-CTT may influence the development and progression of liver cancer by targeting downstream mRNA via metabolic pathways,cancer pathways,and HCC-specific pathways.CONCLUSION The 5’-tiRNA-Lys-CTT levels were higher in early HCC patients.5’-tiRNA-Lys-CTT is a promising diagnostic biomarker for early-stage HCC and may play an oncogenic role in HCC by interacting with downstream mRNA targets via specific pathways. 展开更多
关键词 5’-transfer RNA halve-lysine-CTT Hepatocellular carcinoma transfer RNA-derived small RNAs transfer RNAderived fragments Diagnosis biomarker
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Efficient Transfer of Patients with Critical Illnesses from General Wards to Intensive Care Units
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作者 Chien-Ming Tsao Tzu-Tsui Tsao 《Open Journal of Nursing》 2025年第1期67-77,共11页
Transferring patients with critical illnesses from general wards to intensive care units (ICUs) is a crucial and time-sensitive process. This article presents strategies for improving the efficiency of patient transfe... Transferring patients with critical illnesses from general wards to intensive care units (ICUs) is a crucial and time-sensitive process. This article presents strategies for improving the efficiency of patient transfers, particularly in hospitals where intensive care units are located in buildings separate from general wards. Patient transfers comprise several steps: physicians issue orders, relatives are notified, equipment is prepared, and medical staff coordinate. We identified three factors that influence transfer time: preparation time for bed transfer, time required for shift handovers, and time required for between-ward patient movement. Unfamiliarity with transfer routes and long elevator wait times were factors that also influenced transfer time. The following strategies were proposed: develop a standardized material checklist, design key notes for patient transfers, and optimize transfer routes. These strategies reduced transfer times by 40% to 43%. This study demonstrates that by addressing logistical challenges and streamlining relevant procedures, hospitals can enhance safety and quality of care during patient transfers. 展开更多
关键词 Critical Illnesses Intensive Care Unit (ICU) Patient Safety Time Management transfer Process Optimization Patient transfer
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Liquid-solid mass transfer in micropacked bed reactors with immiscible liquid-liquid two-phase flow
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作者 Yanfu Chen Chu Zhou +1 位作者 Dang Cheng Fener Chen 《Chinese Journal of Chemical Engineering》 2025年第9期1-6,共6页
Herein,the liquid-solid mass trans fer characteristics in micropacked bed reactors(μPBRs)operated with immiscible liquid-liquid two-phase flow is experimentally investigated.It is found that the overall volumetric li... Herein,the liquid-solid mass trans fer characteristics in micropacked bed reactors(μPBRs)operated with immiscible liquid-liquid two-phase flow is experimentally investigated.It is found that the overall volumetric liquid-solid mass transfer coefficient(k_(s)a)increases with the total flow rate and the channelto-particle diameter ratio,while decreases with the organic-to-aqueous phase flow rate ratio.A satisfactory correlation model for calculating k_(s)a of the liquid-liquid μPBRs is developed.The new knowledge obtained would be useful in guiding the design and optimization of the liquid-liquid μPBRs. 展开更多
关键词 MICROREACTOR Packed bed Spherical particle Liquid-liquid-solid system Mass transfer Liquid-liquid-solid transfer model
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Regio-and enantioselective hydrofluorination of internal alkenes via nickel-catalyzed hydrogen atom transfer
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作者 Fan Chen Xiaoyu Zhao +3 位作者 Weihang Miao Yingying Li Ye Yuan Lingling Chu 《Chinese Chemical Letters》 2025年第5期237-242,共6页
Here we present a highly efficient protocol utilizing nickel-hydride hydrogen atom transfer catalysis for the regio-and enantioselective hydrofluorination of internal alkenes.This method efficiently assembles a wide a... Here we present a highly efficient protocol utilizing nickel-hydride hydrogen atom transfer catalysis for the regio-and enantioselective hydrofluorination of internal alkenes.This method efficiently assembles a wide array of enantioenrichedβ-fluoro amides with excellent regio-and enantioselectivity from internal unactivated alkenes.Mechanistic investigations suggest that this transformation proceeds via a NiHhydrogen atom transfer to alkene,followed by a stereoselective fluorine atom transfer process.The weak coordination effect of the tethered amide group is identified as a crucial factor governing the observed regio-and enantioselectivity. 展开更多
关键词 ALKENES HYDROFLUORINATION Hydrogen atom transfer Fluorine atom transfer Nickel catalysis
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Theoretical Study on Photoinduced Triplet Electron Transfer at the Interface of Pd-Octaethylporphyrin and Tungsten Disulfide
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作者 Yang Zhang Wen-Qi Zhao +3 位作者 Wen-Kai Chen Xiao-Ying Xie Wei-Hai Fang Ganglong Cui 《Chinese Journal of Chemical Physics》 2025年第1期113-124,I0050-I0054,I0057,共18页
Heterostructures of organic semi-conductors and transition metal dichalcogenides(TMDs)are viable candidates for superior optoelec-tronic devices.Photoinduced inter-facial charge transfer is crucial for the performance... Heterostructures of organic semi-conductors and transition metal dichalcogenides(TMDs)are viable candidates for superior optoelec-tronic devices.Photoinduced inter-facial charge transfer is crucial for the performance efficiency of such devices,yet the underlying mecha-nism,especially the roles of optical-ly dark triplets and spatially sepa-rated charge transfer states,is poorly understood.In the present work,we obtain the struc-tures of distinct excited states and investigate how they are involved in the charge transfer process at the Pd-octaethylporphyrin(PdOEP)and WS_(2) interface in terms of their energies and couplings.The results show that electron transfer from the triplet PdOEP formed via intersystem crossing prevails over direct electron transfer from the singlet(two orders of magnitude faster).Further analysis reveals that the relatively higher rate of triplet electron transfer compared to singlet electron transfer is mainly attributed to a smaller reorganization energy,which is dominated by the out-of-plane vibrations of the organic component.The work emphasizes the important roles of the optically dark triplets in the electron transfer of the PdOEP@WS_(2) heterostructure,and provides valuable theoretical insights for further improv-ing the optoelectronic performance of TMD-based devices. 展开更多
关键词 Interfacial charge transfer Photoinduced carrier dynamics Theoretical study Pd-octaethylporphyrin Triplet electron transfer Tungsten disulfide
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Factors of intention to learning transfer in apprenticeships:Results and implications of a chain mediation model
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作者 Xin-Xin Chen Young-Sup Hyun Wen-Hao Chen 《Journal of Psychology in Africa》 2025年第3期393-401,共9页
This study utilized a sequential mediating model to examine the role of motivation to learn and transfer selfefficacy in the relationships between perceived content validity,mentoring function,continuous learning work... This study utilized a sequential mediating model to examine the role of motivation to learn and transfer selfefficacy in the relationships between perceived content validity,mentoring function,continuous learning work culture and intention to transfer learning.The sample comprized 429 final-year apprentices in Guangdong province,China(females=69.9%,Engineering&Medicine=69%,mean age=20.99,SD=1.60).The apprentices completed standardized measures of motivation to learn,transfer self-efficacy perceived content validity,mentoring function,and continuous learning work culture.Structural equation modeling was used to analyze the data.Results showed perceived content validity,mentoring function,continuous learning culture to predict intention to transfer learning.Of these factors,perceived content validity was the strongest predictor of intention to transfer learning.Of these factors,perceived content validity was the most influential predictor of intention to transfer learning.The motivation to learn and transfer self-efficacy sequentially mediated the relationship between mentoring function and intention to learning transfer to be stronger than by either alone.Although perceived content validity and continuous learning culture exhibited no significant direct effects on intention to transfer learning,they demonstrated positive indirect associations with intention to transfer via motivation to learn and transfer self-efficacy.These study findings extend the applications of the learning transfer framework to individuals undergoing apprenticeship training which also would apply to other a long-term work-based learning programs. 展开更多
关键词 intention to learning transfer APPRENTICESHIP transfer self-efficacy motivation to learn mentoring function
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Vibration Transfer Function of Railway Vehicle System and its Spatial Coherence Under Vertical Track Irregularity Conditions
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作者 Peng Lu Xi Wang Yu Hou 《Chinese Journal of Mechanical Engineering》 2025年第2期374-393,共20页
Current research on rail vehicle system vibrations primarily relies on numerical methods,with vibration transfer functions commonly derived through data fitting.However,the physical mechanisms underlying these vibrati... Current research on rail vehicle system vibrations primarily relies on numerical methods,with vibration transfer functions commonly derived through data fitting.However,the physical mechanisms underlying these vibrations are not well understood.To clarify the vibration transfer function and its characteristics,four basic input vectors are defined,and an analytical method is proposed.The vibration transfer functions of the vehicle system are solved,and their spatial coherence is analyzed.The results show that there are two spatial scales and four coherent modes in the vehicle system.The track irregularity wavelengths are combined with two spatial scales to alter the proportions of basic input vectors and then show the characteristics of spatial coherence.Four coherent modes are involved in wheel-rail force and primary suspension force;two coherent modes are involved in bogie vertical motion;and their dominant modes vary with the input frequency.On the other hand,the coherent modes involved in the bogie pitching motion and vehicle body motion are single and fixed over the whole range of frequency.This study presents an analytical method for the rapid solution of dynamic responses in vehicle systems and systematically analyzes the coherence behavior of vibration transfer functions with respect to tracking irregularity wavelengths. 展开更多
关键词 Vertical track irregularity Vibration transfer function Spatial coherence Dominant mode transfer matrix method
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Experimental and Numerical Study on Flow and Heat Transfer Characteristics in Rectangular Channels with Leaf-Shaped Pin Fins
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作者 Chao Zhang Runze Yan +2 位作者 Honghui Li Qingheng Tang Qinghai Zhao 《Frontiers in Heat and Mass Transfer》 2025年第2期421-440,共20页
The growing need for enhanced heat dissipation is compelling the development of more effective heat exchangers.Innovation inspired by nature bionics,four types of leaf-shaped pin fins were proposed and four combinatio... The growing need for enhanced heat dissipation is compelling the development of more effective heat exchangers.Innovation inspired by nature bionics,four types of leaf-shaped pin fins were proposed and four combinations of them were considered.The leaf-shaped design of the cooling pin fin enhances uniformity and synergy,effectively creating an optimized flow path that boosts cooling performance.Eight three-dimensional conjugate heat transfer models in staggered arrangement were developed using ANSYS-Fluent software.Aluminum6061material was used as the heat sinkmaterial and single-phase liquid water flowed through the rectangular channel where the Reynolds(R_(e))number varies from 40 to 100.Using the same boundary conditions as the software simulations,two leaf-shaped channels were printed to validate numerical models.Velocity field and temperature differences of the eight proposed leaf-shaped pin fins configurations were discussed by comparison with cylindrical pin fins.Based on the findings of this study,at a Reynolds number of 80,the Leaf B Staggered Array(LBSA)records a maximum temperature that is 0.72 K lower than that of the cylindrical pin fins arrangement.Additionally,the LBSA exhibits a reduction in the friction factor by approximately 33.3%relative to the circular pin fins array under the same R_(e).This implies that the design of LBSA has been optimized to provide better heat dissipation performance while maintaining lower energy consumption.Furthermore,the LBSA demonstrates the most favorable thermal-hydraulic performance index(TPI),which is 1.18 times higher than that of the circular pin fins arrangement at R_(e)=80.The temperature reduction and friction factor reduction of the lobed channel is more pronounced than that of the conventional cooling channel,highlighting its potential to increase heat transfer efficiency and reduce energy consumption in practical applications. 展开更多
关键词 Heat transfer enhancement leaf-shaped pin fins rectangular channel single-phase heat transfer staggered arrangement
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Experimental Study of Forced Convective Heat Transfer in a Copper Tube Using Three Types of Nanofluids
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作者 Zahraa N.Hussain Jamal M.Ali +2 位作者 Hasan S.Majdi Abbas J.Sultan H.Al-Naseri 《Fluid Dynamics & Materials Processing》 2025年第2期351-370,共20页
The use of nanofluids as heat transfer media represents an innovative strategy to enhance heat transfer performances.This study investigates experimentally the turbulent convective heat transfer characteristics of wat... The use of nanofluids as heat transfer media represents an innovative strategy to enhance heat transfer performances.This study investigates experimentally the turbulent convective heat transfer characteristics of waterbased nanofluids containing TiO_(2),CuO,and graphene nanoplatelet(GNP)nanoparticles as they flow through a copper tube.Both the dynamic viscosity and thermal conductivity of these nanofluids were modeled and experimentally measured across varying nanoparticle concentrations(0.01,0.02,and 0.03 vol.%)and temperatures(25℃,35℃,and 45℃).The findings indicate that the behavior of nanofluids depends on the parameter used for comparison with the base fluid.Notably,both the friction factor and heat transfer coefficient increase with higher nanoparticle volume concentrations at a constant Reynolds number.The results further reveal that the GNP/water nanofluid,with a volume concentration of 0.03%at 45℃,exhibit the highest Nusselt number,followed by the CuO/water and TiO_(2)/water nanofluids,with respective increases of 17.8%,11.09%,and 8.11%. 展开更多
关键词 NANOFLUID heat transfer coefficient thermal conductivity heat transfer enhancement
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Face-to-face π-π interactions and electron communication boosting efficient reverse intersystem crossing in through-space charge transfer molecules
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作者 Manlin Lu Sheng Liao +6 位作者 Jiayu Li Zidong Yu Ningjiu Zhao Zuoti Xie Shunli Chen Li Dang Ming-De Li 《Chinese Chemical Letters》 2025年第6期764-771,共8页
The excited state dynamics and critically regulated factors of reverse intersystem crossing(RISC)in through-space charge transfer(TSCT)molecules have received insufficient attention.Here,five molecules of through spac... The excited state dynamics and critically regulated factors of reverse intersystem crossing(RISC)in through-space charge transfer(TSCT)molecules have received insufficient attention.Here,five molecules of through space/bond charge transfer inducing thermally activated delayed fluorescence(TADF)are prepared,and their excited state charge transfer processes are studied by ultrafast transient absorption and theoretical calculations.DM-Z has a largerΔEST,leading to a longer lifetime of intersystem crossing(ISC),resulting in the lowest photoluminescence quantum yield(PLQY).Oppositely,ISC and RISC are demonstrated to take place with shorter lifetimes for TSCT molecules.The face-to-faceπ-πstacking interactions and electron communication enable DM-B and DM-BX to have an efficient RISC,increasing the weight coefficient of RISC from 1.7%(DM-X)to close to 50%(DM-B and DM-BX)in the solvents,which make DM-BX and DM-B to have a high PLQY.However,partial local excitation in the donor center is observed and the charge transfer is decreased for DM-G and DM-X.The triplet excited state(DM-G)or singlet excited state(DM-X)mainly undergoes inactivation through a non-radiative relaxation process,resulting in less RISC and low PLQY.This work provides theoretical hints to enhance the RISC process in the TADF materials. 展开更多
关键词 Through-space charge transfer Reverse intersystem crossing Thermally activated delayed fluorescence Transient absorption Through-bond charge transfer
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Overcoming voltage issue in bicarbonate electrolysis:Dual mass-transfer pathways for CO_(2)and ions
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作者 Sae In Suh Youngrok Lee +3 位作者 Jae-young Choi Hansung Kim Hyung-Suk Oh Woong Hee Lee 《Journal of Energy Chemistry》 2025年第11期427-433,I0011,共8页
The direct electrolysis of CO_(2)-captured liquid,such as bicarbonate,offers economic advantages by eliminating the CO_(2)regeneration step.However,high cell voltages remain a major barrier.Herein,we propose a new str... The direct electrolysis of CO_(2)-captured liquid,such as bicarbonate,offers economic advantages by eliminating the CO_(2)regeneration step.However,high cell voltages remain a major barrier.Herein,we propose a new strategy to build dual mass-transfer pathways for CO_(2)and ions using a carbon and anion exchange ionomer(AEI)to reduce cell voltages while achieving sufficient Faradaic efficiency(FE)for the CO_(2)reduction reaction.By optimizing the interposer materials and ratio of carbon,Ag,and AEI,sufficient FECO(57%)and low cell voltages(3.17 V)were achieved at 100 mA cm^(-2).The formation of dual masstransfer pathways in bicarbonate electrolysis was confirmed through in situ/operando visualization studies.To ensure stability,we recommend the generation of dual mass-transfer pathways using chemically and physically stable materials.Our work provides an understanding of the mass transfer in bicarbonate electrolysis and a direction for overcoming the voltage issue. 展开更多
关键词 CO_(2)electroreduction Bicarbonate reduction CO_(2)capture solution Mass transfer Ion transfer VOLTAGE
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Three-Stage Heat Transfer Pathways in the Latent Heat Thermal Energy Storage System With Solid–Liquid Phase-Change Materials
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作者 Qian Xu Di Yang +9 位作者 Caixia Yang Pengxiang Zhao Andrey A.Shiryaev Ruitao Zhang Gang Li Huachao Yang Haihong Wang Yiyao Ge Yong Zang Yulong Ding 《Carbon Energy》 2025年第12期40-70,共31页
The latent heat thermal energy storage system with solid-liquid phase-change material(SLPCM-LHTES)as energy storage medium provides outstanding advantages such as system simplicity,stable temperature control,and high ... The latent heat thermal energy storage system with solid-liquid phase-change material(SLPCM-LHTES)as energy storage medium provides outstanding advantages such as system simplicity,stable temperature control,and high energy storage density,showing great potential toward addressing the energy storage problems associated with decentralized,intermittent,and unstable renewable energy sources.Notably,effective heat transfer within the SLPCM-LHTES is crucial for extending its application potential.Therefore,a comprehensive understanding of the heat transfer processes in SLPCM-LHTES from a theoretical perspective is necessary.In this review,we propose a three-stage heat transfer pathway in SLPCM-LHTES,including external heating,interfacial heat transfer,and intrinsic phase transition processes.From the perspective of this three-stage pathway,the theoretical basis of heat transfer processes and typical efficiency enhancement strategies in SLPCM-LHTES are summarized.Moreover,an overview of the typical applications of SLPCM-LHTES in various fields,such as building energy efficiency,textiles and garments,and battery thermal management,is presented.Finally,the remaining challenges and possible avenues of research in this burgeoning field will also be discussed. 展开更多
关键词 heat transfer efficiency latent heat thermal energy storage phase-change material three-stage heat transfer pathway
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Enhancing Adversarial Example Transferability via Regularized Constrained Feature Layer
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作者 Xiaoyin Yi Long Chen +2 位作者 Jiacheng Huang Ning Yu Qian Huang 《Computers, Materials & Continua》 2025年第4期157-175,共19页
Transfer-based Adversarial Attacks(TAAs)can deceive a victim model even without prior knowledge.This is achieved by leveraging the property of adversarial examples.That is,when generated from a surrogate model,they re... Transfer-based Adversarial Attacks(TAAs)can deceive a victim model even without prior knowledge.This is achieved by leveraging the property of adversarial examples.That is,when generated from a surrogate model,they retain their features if applied to other models due to their good transferability.However,adversarial examples often exhibit overfitting,as they are tailored to exploit the particular architecture and feature representation of source models.Consequently,when attempting black-box transfer attacks on different target models,their effectiveness is decreased.To solve this problem,this study proposes an approach based on a Regularized Constrained Feature Layer(RCFL).The proposed method first uses regularization constraints to attenuate the initial examples of low-frequency components.Perturbations are then added to a pre-specified layer of the source model using the back-propagation technique,in order to modify the original adversarial examples.Afterward,a regularized loss function is used to enhance the black-box transferability between different target models.The proposed method is finally tested on the ImageNet,CIFAR-100,and Stanford Car datasets with various target models,The obtained results demonstrate that it achieves a significantly higher transfer-based adversarial attack success rate compared with baseline techniques. 展开更多
关键词 Adversarial examples black-box transferability regularized constrained transfer-based adversarial attacks
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Overview of Earth-Moon Transfer Trajectory Modeling and Design 被引量:2
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作者 Jiye Zhang Huichang Yu Honghua Dai 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第4期5-43,共39页
TheMoon is the only celestial body that human beings have visited.The design of the Earth-Moon transfer orbits is a critical issue in lunar exploration missions.In the 21st century,new lunar missions including the con... TheMoon is the only celestial body that human beings have visited.The design of the Earth-Moon transfer orbits is a critical issue in lunar exploration missions.In the 21st century,new lunar missions including the construction of the lunar space station,the permanent lunar base,and the Earth-Moon transportation network have been proposed,requiring low-cost,expansive launch windows and a fixed arrival epoch for any launch date within the launch window.The low-energy and low-thrust transfers are promising strategies to satisfy the demands.This review provides a detailed landscape of Earth-Moon transfer trajectory design processes,from the traditional patched conic to the state-of-the-art low-energy and low-thrust methods.Essential mechanisms of the various utilized dynamic models and the characteristics of the different design methods are discussed in hopes of helping readers grasp thebasic overviewof the current Earth-Moon transfer orbitdesignmethods anda deep academic background is unnecessary for the context understanding. 展开更多
关键词 Earth-Moon transfer traditional direct transfer low-energy transfer manifold theory weak stability boundary theory low-thrust transfer
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Identification algorithm of low-count energy spectra under short-duration measurement based on heterogeneous sample transfer 被引量:1
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作者 Hao-Lin Liu Hai-Bo Ji +1 位作者 Jiang-Mei Zhang Jing Lu 《Nuclear Science and Techniques》 2025年第3期12-26,共15页
In scenarios such as vehicle radiation monitoring and unmanned aerial vehicle radiation detection,rapid measurements using a NaI(Tl)detector often result in low photon counts,weak characteristic peaks,and significant ... In scenarios such as vehicle radiation monitoring and unmanned aerial vehicle radiation detection,rapid measurements using a NaI(Tl)detector often result in low photon counts,weak characteristic peaks,and significant statistical fluctuations.These issues can lead to potential failures in peak-searching-based identification methods.To address the low precision associated with short-duration measurements of radionuclides,this paper proposes an identification algorithm that leverages heterogeneous spectral transfer to develop a low-count energy spectral identification model.Comparative experiments demonstrated that transferring samples from 26 classes of simulated heterogeneous gamma spectra aids in creating a reliable model for measured gamma spectra.With only 10%of target domain samples used for training,the accuracy on real low-count spectral samples was 95.56%.This performance shows a significant improvement over widely employed full-spectrum analysis methods trained on target domain samples.The proposed method also exhibits strong generalization capabilities,effectively mitigating overfitting issues in low-count energy spectral classification under short-duration measurements. 展开更多
关键词 Radionuclide identification Low-count Gamma energy spectral analysis HETEROGENEOUS transfer learning
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In situ growth of iron incorporated Ni_(3)S_(2)nanosheet on nickel foam in mediating electron transfer to peroxymonosulfate for pollutant abatement 被引量:1
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作者 Yunjin Yao Zhongming Tao +5 位作者 Hongwei Hu Lijie Zhang Ziwei Ma Yaoyao Wang Shiyang Lin Shaobin Wang 《Journal of Environmental Sciences》 2025年第4期704-718,共15页
Catalytic oxidation of organic pollutants is a well-known and effective technique for pollutant abatement.Unfortunately,this method is significantly hindered in practical applications by the lowefficiency and difficul... Catalytic oxidation of organic pollutants is a well-known and effective technique for pollutant abatement.Unfortunately,this method is significantly hindered in practical applications by the lowefficiency and difficult recovery of the catalysts in a powdery form.Herein,a three-dimensional(3D)framework of Fe-incorporated Ni_(3)S_(2)nanosheets in-situ grown on Ni foam(Fe-Ni_(3)S_(2)@NF)was fabricated by a facile two-step hydrothermal process and applied to trigger peroxymonosulfate(PMS)oxidation of organic compounds inwater.A homogeneous growth environment enabled the uniform and scalable growth of Fe-Ni_(3)S_(2)nanosheets on the Ni foam.Fe-Ni_(3)S_(2)@NF possessed outstanding activity and durability in activating PMS,as it effectively facilitated electron transfer from organic pollutants to PMS.Fe-Ni_(3)S_(2)@NF initially supplied electrons to PMS,causing the catalyst to undergo oxidation,and subsequently accepted electrons from organic compounds,returning to its initial state.The introduction of Fe into the Ni_(3)S_(2)lattice enhanced electrical conductivity,promoting mediated electron transfer between PMS and organic compounds.The 3D conductive Ni foam provided an ideal platform for the nucleation and growth of Fe-Ni_(3)S_(2),accelerating pollutant abatement due to its porous structure and high conductivity.Furthermore,its monolithic nature simplified the catalyst recycling process.A continuous flow packed-bed reactor by encapsulating Fe-Ni_(3)S_(2)@NF catalyst achieved complete pollutant abatement with continuous operation for 240 h,highlighting its immense potential for practical environmental remediation.This study presents a facile synthesis method for creating a novel type of monolithic catalyst with high activity and durability for decontamination through Fenton-like processes. 展开更多
关键词 Nickel foam Organic pollutants Persulfate activation Non-radical pathway Electron transfer
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The role of mitochondria transfer in cancer biological behavior,the immune system and therapeutic resistance 被引量:1
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作者 Xintong Lyu Yangyang Yu +2 位作者 Yuanjun Jiang Zhiyuan Li Qiao Qiao 《Journal of Pharmaceutical Analysis》 2025年第3期511-522,共12页
Mitochondria play a crucial role as organelles,managing several physiological processes such as redox balance,cell metabolism,and energy synthesis.Initially,the assumption was that mitochondria primarily resided in th... Mitochondria play a crucial role as organelles,managing several physiological processes such as redox balance,cell metabolism,and energy synthesis.Initially,the assumption was that mitochondria primarily resided in the host cells and could exclusively transmit from oocytes to offspring by a mechanism known as vertical inheritance of mitochondria.Recent scholarly works,however,suggest that certain cell types transmit their mitochondria to other developmental cell types via a mechanism referred to as intercellular or horizontal mitochondrial transfer.This review details the process of which mitochondria are transferred across cells and explains the impact of mitochondrial transfer between cells on the efficacy and functionality of cancer cells in various cancer forms.Specifically,we review the role of mitochondria transfer in regulating cellular metabolism restoration,excess reactive oxygen species(ROS)generation,proliferation,invasion,metastasis,mitophagy activation,mitochondrial DNA(mtDNA)inheritance,immune system modulation and therapeutic resistance in cancer.Additionally,we highlight the possibility of using intercellular mitochondria transfer as a therapeutic approach to treat cancer and enhance the efficacy of cancer treatments. 展开更多
关键词 Mitochondria transfer Cancer biological behavior Immune system Therapeutic resistance
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MXene-induced electronic structure modulation of Fe-Al-LDH to boost the Fenton-like Reaction:Singlet oxygen evolution and electron-transfer mechanisms 被引量:1
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作者 Zhongzhu Yang Zeyan Zhou +2 位作者 Xiaofei Tan Guangming Zeng Chang Zhang 《Journal of Materials Science & Technology》 2025年第1期224-237,共14页
Layered double hydroxide(LDH)based heterogonous peroxymonosulfate(PMS)activation degradation of pollutants has attracted extensive attention.The challenge is to selectively regulate the traditional free radical domina... Layered double hydroxide(LDH)based heterogonous peroxymonosulfate(PMS)activation degradation of pollutants has attracted extensive attention.The challenge is to selectively regulate the traditional free radical dominant degradation pathway into a nonradical degradation pathway.Herein,an interface ar-chitecture of Ti_(3) C_(2) T_(x)-MXene(MXene)loading on the Fe-Al LDH scaffold was developed,which showed excellent stability and robust resistance against harsh conditions.Significantly,the rate constant for tetra-cycline hydrochloride(TC)degradation in the MXene-LDH/PMS process was 0.421 min^(-1),which was ten times faster than the rate constant for pure Fe-Al LDH(0.042 min^(-1)).Specifically,more reactive Fe with the closer d-band center to the Fermi level results in higher electron transfer efficiency.The occupa-tions of Fe-3d orbitals in Mxene/Fe-Al LDH are pushed above the Fermi level to generate,which results in higher PMS adsorption and inhibition of the release of oxygen-containing active species intermedi-ates,leading to the enhanced^(1)O_(2) generation.Additionally,the built-in electric field in the heterojunc-tion was driven by the charge redistribution between MXene and Fe-Al LDH,resulting in a mediated-electron transfer mechanism,differentiating it from the Fe-Al LDH/PMS system.It was fascinating that MXene/Fe-Al LDH achieved satisfactory treatment efficiency in continuous column reactor and real landfill leachate. 展开更多
关键词 Interface engineering Density functional theory Layered double hydroxides PEROXYMONOSULFATE Electron transfer
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