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Electrospun Nanofibrous Transition Metal-based Bifunctional Electrocatalysts Toward Overall Water Splitting
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作者 YIN Yongting LU Xiaofeng 《高等学校化学学报》 北大核心 2026年第1期87-107,共21页
Electrochemical water splitting represents a sustainable technology for hydrogen(H_(2))production.However,its large-scale implementation is hindered by the high overpotentials required for both the cathodic hydrogen e... Electrochemical water splitting represents a sustainable technology for hydrogen(H_(2))production.However,its large-scale implementation is hindered by the high overpotentials required for both the cathodic hydrogen evolution reaction(HER)and the anodic oxygen evolution reaction(OER).Transition metal-based catalysts have garnered significant research interest as promising alternatives to noble-metal catalysts,owing to their low cost,tunable composition,and noble-metal-like catalytic activity.Nevertheless,systematic reviews on their application as bifunctional catalysts for overall water splitting(OWS)are still limited.This review comprehensively outlines the principal categories of bifunctional transition metal electrocatalysts derived from electrospun nanofibers(NFs),including metals,oxides,phosphides,sulfides,and carbides.Key strategies for enhancing their catalytic performance are systematically summarized,such as heterointerface engineering,heteroatom doping,metal-nonmetal-metal bridging architectures,and single-atom site design.Finally,current challenges and future research directions are discussed,aiming to provide insightful perspectives for the rational design of high-performance electrocatalysts for OWS. 展开更多
关键词 Electrospinning Nanofibers Transition metal-based catalyst Overall water splitting Performance optimization
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Ultrathin Pd based bimetallic nanowires as highly efficient ampere-level pH-universal water splitting
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作者 Yuanwei Ma Jigang Wang +4 位作者 Zhaodi Yan Qiang Liu Lanyan Li Zhongfang Li Likai Wang 《Chinese Chemical Letters》 2026年第1期350-355,共6页
Herein,we have developed a straightforward wet-chemical method to synthesize a series of Pd-based alloy nanowires(NWs),including Pd Pt NWs,Pd Au NWs,Pd Ir NWs,and Pd Ru NWs,which exhibits high mass activity and turnov... Herein,we have developed a straightforward wet-chemical method to synthesize a series of Pd-based alloy nanowires(NWs),including Pd Pt NWs,Pd Au NWs,Pd Ir NWs,and Pd Ru NWs,which exhibits high mass activity and turnover frequency(TOF) for HER,surpassing Pt/C by 4.6-fold and 1.5-fold in acidic and alkaline electrolytes,respectively.It also demonstrates high stability in alkaline electrolyte at a current density of 220 m A/cm^(2) for 280 h,highlighting its potential for practical applications under industrial current conditions.Pd Pt NWs exhibited ultrathin structures with head-to-tail kinks and inherent defects,significantly increasing the density of active sites and precisely tuning the electronic structure,which could accelerate reaction kinetics and boost water-splitting electrocatalytic performance.This study highlights the potential of Pd Pt NWs as highly efficient catalysts,offering outstanding catalytic performance and stability for practical applications. 展开更多
关键词 PdPt ALLOY NANOWIRES Water splitting HER
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Mitigating Attribute Inference in Split Learning via Channel Pruning and Adversarial Training
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作者 Afnan Alhindi Saad Al-Ahmadi Mohamed Maher Ben Ismail 《Computers, Materials & Continua》 2026年第3期1465-1489,共25页
Split Learning(SL)has been promoted as a promising collaborative machine learning technique designed to address data privacy and resource efficiency.Specifically,neural networks are divided into client and server subn... Split Learning(SL)has been promoted as a promising collaborative machine learning technique designed to address data privacy and resource efficiency.Specifically,neural networks are divided into client and server subnetworks in order to mitigate the exposure of sensitive data and reduce the overhead on client devices,thereby making SL particularly suitable for resource-constrained devices.Although SL prevents the direct transmission of raw data,it does not alleviate entirely the risk of privacy breaches.In fact,the data intermediately transmitted to the server sub-model may include patterns or information that could reveal sensitive data.Moreover,achieving a balance between model utility and data privacy has emerged as a challenging problem.In this article,we propose a novel defense approach that combines:(i)Adversarial learning,and(ii)Network channel pruning.In particular,the proposed adversarial learning approach is specifically designed to reduce the risk of private data exposure while maintaining high performance for the utility task.On the other hand,the suggested channel pruning enables the model to adaptively adjust and reactivate pruned channels while conducting adversarial training.The integration of these two techniques reduces the informativeness of the intermediate data transmitted by the client sub-model,thereby enhancing its robustness against attribute inference attacks without adding significant computational overhead,making it wellsuited for IoT devices,mobile platforms,and Internet of Vehicles(IoV)scenarios.The proposed defense approach was evaluated using EfficientNet-B0,a widely adopted compact model,along with three benchmark datasets.The obtained results showcased its superior defense capability against attribute inference attacks compared to existing state-of-the-art methods.This research’s findings demonstrated the effectiveness of the proposed channel pruning-based adversarial training approach in achieving the intended compromise between utility and privacy within SL frameworks.In fact,the classification accuracy attained by the attackers witnessed a drastic decrease of 70%. 展开更多
关键词 split learning privacy-preserving split learning distributed collaborative machine learning channel pruning adversarial learning resource-constrained devices
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The interface engineering strategy assists the 3D core-shell structure Co_(3)S_(4)/CuS@NiFe LDH nanocoral spheres to achieve significant overall water splitting
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作者 Jun Yu Yangping Zhang +6 位作者 Nannan Zhang Jie Li Huiyu Sun Xinyu Gu Changqing Ye Tianpeng Liu Yukou Du 《Chinese Chemical Letters》 2026年第2期570-576,共7页
Designing a highly active and stable bifunctional catalyst is essential for achieving superior overall water splitting(OWS).In this study,a three-dimensional(3D)core-shell structure Co_(3)S_(4)/CuS@NiFe LDH nanocoral ... Designing a highly active and stable bifunctional catalyst is essential for achieving superior overall water splitting(OWS).In this study,a three-dimensional(3D)core-shell structure Co_(3)S_(4)/CuS@NiFe LDH nanocoral spheres electrocatalyst was constructed on nickel foam(NF)via an interfacial engineering strategy.This 3D core-shell heterostructure maximizes the exposure of active sites,optimizes the charge transport pathway and accelerates gas release rates.The protective shell strategy of NiFe LDH provides favorable stability,which contributes to inhibiting the electrochemical corrosion of the electrocatalyst and mitigating the toxic effects of Cl−and other microorganisms during the seawater splitting process.Moreover,the introduction of NiFe LDH induces a change in the OER mechanism from an adsorption evolution mechanism(AEM)to a lattice oxygen mechanism(LOM),which improves the intrinsic activity of the catalyst.Consequently,Co_(3)S_(4)/CuS@NiFe LDH demonstrates exceptional performance in the oxygen evolution reaction(OER)(η100=251 mV)and in the hydrogen evolution reaction(HER)(η100=254 mV),alongside remarkable stability over 100 h.For OWS,it exhibits a voltage of 1.46 V at 10 mA/cm^(2) and maintain stability for 100 h.Impressively,Co_(3)S_(4)/CuS@NiFe LDH still possesses outstanding activity and stability in natural alkaline seawater.This work proposes interfacial engineering to construct bifunctional catalysts with core-shell heterostructures,providing instructive guidelines for the design of highly efficient electrocatalysts toward seawater electrolysis. 展开更多
关键词 Core-shell structure Layered double hydroxides Transition metal sulphides Bifunctional catalyst Overall water splitting Overall seawater splitting
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A Kind of Fast Iterative Methods With the Application Based on Diagonal Matrix Splitting
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作者 XU Qiuyan 《宁夏大学学报(自然科学版中英文)》 2026年第1期1-13,共13页
The fast solution of linear equations has always been one of the hot spots in scientific computing.A kind of the diagonal matrix splitting iteration methods are provided,which is different from the classical matrix sp... The fast solution of linear equations has always been one of the hot spots in scientific computing.A kind of the diagonal matrix splitting iteration methods are provided,which is different from the classical matrix splitting methods.Taking the decomposition of the diagonal elements for coefficient matrix as the key point,some new preconditioners are constructed.Taking the tri-diagonal coefficient matrix as an example,the convergence domains and optimal relaxation factor of the new method are analyzed theoretically.The presented new iteration methods are applied to solve linear algebraic equations,even 2D and 3D diffusion problems with the fully implicit discretization.The results of numerical experiments are matched with the theoretical analysis,and show that the iteration numbers are reduced greatly.The superiorities of presented iteration methods exceed some classical iteration methods dramatically. 展开更多
关键词 ITERATION matrix splitting diffusion equation CONVERGENCE optimal relaxation factor
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Patients with hepatocellular carcinoma achieving a complete response to sorafenib:Three case reports and review of literature
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作者 Hana Lučev Gordan Adžić +1 位作者 Stjepko Pleština Juraj Prejac 《World Journal of Gastrointestinal Oncology》 2026年第1期233-241,共9页
BACKGROUND Sorafenib has been the conventional treatment for advanced hepatocellular carcinoma(HCC)since 2008.While radiological complete responses are extremely rare,improved supportive care and multidisciplinary app... BACKGROUND Sorafenib has been the conventional treatment for advanced hepatocellular carcinoma(HCC)since 2008.While radiological complete responses are extremely rare,improved supportive care and multidisciplinary approaches in clinical practice may explain the recent increase in case reports and retrospective series documenting such responses.CASE SUMMARY This case series describes 3 patients with advanced HCC who achieved durable complete responses using first-line sorafenib therapy,even in the presence of portal vein thrombosis or extrahepatic spread,and highlights the potential for sustained remission in selected patients.Dermatologic toxicity and non-viral etiology may correlate with favorable outcomes;however,reliable predictive biomarkers for sorafenib response are lacking.CONCLUSION Future research into the etiology and molecular differences in HCC is necessary to develop more personalized therapy options. 展开更多
关键词 Hepatocellular carcinoma SORAFENIB complete response Tyrosine kinase inhibitor Case report
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Ruthenium-based electrocatalysts toward electrochemical water splitting
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作者 Luzheng Zhou Hongzhi Cui +6 位作者 Yehao Li Minggang Zhao Kaibo Wang Zhenhua Yan Kun Jiang Leigang Li Xiaoqing Huang 《Science China Materials》 2026年第3期1317-1368,共52页
Ruthenium-based materials(Ru and RuO_(2))are promising electrocatalysts toward electrochemical water splitting(EWS)though there are still issues with them that needs to be resolved such as relatively strong adsorption... Ruthenium-based materials(Ru and RuO_(2))are promising electrocatalysts toward electrochemical water splitting(EWS)though there are still issues with them that needs to be resolved such as relatively strong adsorption strength of intermediates over Ru and oxidative dissolution of RuO_(2).In this article,an overview of the recent progress and challenges with Ru-based electrocatalysts for EWS is provided.Firstly,fundamentals of EWS are summarized from the aspects of reaction mechanisms and activity descriptors.Next,the typical methods of fabricating Ru-based catalysts are demonstrated mainly including hydrothermal/solvothermal syntheses,organic ligand-assisted syntheses,pyrolysis,acid etching,cation exchange methods and molten salt-assisted syntheses.We then focus on illustrating the enhancing strategies toward creating advanced Ru-based electrocatalysts by demonstrating the typical examples,which include alloying,doping,structure design,interface engineering,single-atom catalyst design,high-entropy alloy design,phase engineering and defecting engineering.In this section,the structureproperty correlation is elucidated aiming to the design of more efficient Ru-based electrocatalysts for EWS.Finally,we conclude the review by addressing the challenges and prospects of electrochemical water splitting and the development of Rubased catalysts. 展开更多
关键词 RUTHENIUM hydrogen evolution reaction oxygen evolution reaction electrocatalytic water splitting hydrogen energy
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Unlocking Edge Fine-Tuning:A Sample-Efficient Language-Empowered Split Fine-Tuning Framework
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作者 Zuyi Huang Yue Wang +4 位作者 Jia Liu Haodong Yi Lejun Ai Min Chen Salman A.AlQahtani 《Computers, Materials & Continua》 2026年第4期1584-1606,共23页
The personalized fine-tuning of large languagemodels(LLMs)on edge devices is severely constrained by limited computation resources.Although split federated learning alleviates on-device burdens,its effectiveness dimin... The personalized fine-tuning of large languagemodels(LLMs)on edge devices is severely constrained by limited computation resources.Although split federated learning alleviates on-device burdens,its effectiveness diminishes in few-shot reasoning scenarios due to the low data efficiency of conventional supervised fine-tuning,which leads to excessive communication overhead.To address this,we propose Language-Empowered Split Fine-Tuning(LESFT),a framework that integrates split architectures with a contrastive-inspired fine-tuning paradigm.LESFT simultaneously learns frommultiple logically equivalent but linguistically diverse reasoning chains,providing richer supervisory signals and improving data efficiency.This process-oriented training allows more effective reasoning adaptation with fewer samples.Extensive experiments demonstrate that LESFT consistently outperforms strong baselines such as SplitLoRA in task accuracy.LESFT consistently outperforms strong baselines on GSM8K,CommonsenseQA,and AQUA_RAT,with the largest gains observed on Qwen2.5-3B.These results indicate that LESFT can effectively adapt large language models for reasoning tasks under the computational and communication constraints of edge environments. 展开更多
关键词 Large language models edge computing efficient fine-tuning few-shot fine-tuning split federated learning
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OptimizationDesign and Numerical Simulation of Variable Tube Diameter Heat Exchanger for Split Air Conditioning Indoor Unit
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作者 Zheming Cheng Xinping Ou Yang +2 位作者 Leren Tao Zihao Wang Ke Sun 《Frontiers in Heat and Mass Transfer》 2026年第1期288-313,共26页
Energy shortage has become one of themost concerning issues in the world today,and improving energy utilization efficiency is a key area of research for experts and scholars worldwide.Small-diameter heat exchangers of... Energy shortage has become one of themost concerning issues in the world today,and improving energy utilization efficiency is a key area of research for experts and scholars worldwide.Small-diameter heat exchangers offer advantages such as reduced material usage,lower refrigerant charge,and compact structure.However,they also face challenges,including increased refrigerant pressure drop and smaller heat transfer area inside the tubes.This paper combines the advantages and disadvantages of both small and large-diameter tubes and proposes a combined-diameter heat exchanger,consisting of large and small diameters,for use in the indoor units of split-type air conditioners.There are relatively few studies in this area.In this paper,A theoretical and numerical computation method is employed to establish a theoretical-numerical calculation model,and its reliability is verified through experiments.Using this model,the optimal combined diameters and flow path design for a combined-diameter heat exchanger using R32 as the working fluid are derived.The results show that the heat transfer performance of all combined diameter configurations improves by 2.79%to 8.26%compared to the baseline design,with the coefficient of performance(COP)increasing from 4.15 to 4.27~4.5.These designs can save copper material,but at the cost of an increase in pressure drop by 66.86%to 131.84%.The scheme IIIH,using R32,is the optimal combined-diameter and flow path configuration that balances both heat transfer performance and economic cost. 展开更多
关键词 split air condition variable tube diameter enhanced heat transfer numerical simulation structural design optimization
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A case report with the progression from atrial fibrillation to complete AV block, heart failure and electrical storm
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作者 Shi-Xing LI Xiang-Min SHI +1 位作者 Jian LI Chuang ZHANG 《Journal of Geriatric Cardiology》 2026年第1期65-68,共4页
When patients initially present with atrial fibrillation along with an enlarged heart and heart failure, followed by atrioventricular block, it's essential to consider genetic factors.^([1])Genetic testing can off... When patients initially present with atrial fibrillation along with an enlarged heart and heart failure, followed by atrioventricular block, it's essential to consider genetic factors.^([1])Genetic testing can offer crucial diagnostic evidence, aiding in prognosis assessment and the adoption of appropriate treatment strategies. 展开更多
关键词 heart failure atrial fibrillation enlarged heart atrioventricular block genetic factors genetic testing adoption appropriate treatment strategies complete av block prognosis assessment
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基于分类估计的异质数据融合M_(split)模型 被引量:1
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作者 陶叶青 束明聪 陈浩 《淮阴师范学院学报(自然科学版)》 2025年第1期45-51,共7页
从分类估计的角度研究异质数据融合理论,建立一种不依赖于随机模型的融合方法.该理论首先基于M_(split)估计对观测数据进行分类估计,然后根据分类估计结果,应用中位函数计算不同参数估值的中误差,最后通过定义尺度因子与相对权比函数构... 从分类估计的角度研究异质数据融合理论,建立一种不依赖于随机模型的融合方法.该理论首先基于M_(split)估计对观测数据进行分类估计,然后根据分类估计结果,应用中位函数计算不同参数估值的中误差,最后通过定义尺度因子与相对权比函数构建融合模型,实现异质数据的有效融合.通过两类不同精度量级的观测数据组成的控制测量实例对该方法进行验证,结果表明,该方法易于实现,得到的参数估值稳定. 展开更多
关键词 异质数据融合 分类估计 M_(split)估计 尺度因子 融合模型
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Complete or partial split in associating liver partition and portal vein ligation for staged hepatectomy: A systematic review and meta-analysis 被引量:5
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作者 Han-Chun Huang Jin Bian +4 位作者 Yi Bai Xin Lu Yi-Yao Xu Xin-Ting Sang Hai-Tao Zhao 《World Journal of Gastroenterology》 SCIE CAS 2019年第39期6016-6024,共9页
BACKGROUND Associating liver partition and portal vein ligation for staged hepatectomy(ALPPS)has been adopted by liver surgeons in recent years.However,high morbidity and mortality rates have limited the promotion of ... BACKGROUND Associating liver partition and portal vein ligation for staged hepatectomy(ALPPS)has been adopted by liver surgeons in recent years.However,high morbidity and mortality rates have limited the promotion of this technique.Some recent studies have suggested that ALPPS with a partial split can effectively induce the growth of future liver remnant(FLR)similar to a complete split with better postoperative safety profiles.However,some others have suggested that ALPPS can induce more rapid and adequate FLR growth,but with the same postoperative morbidity and mortality rates as in partial split of the liver parenchyma in ALPPS(p-ALPPS).AIM To perform a systematic review and meta-analysis on ALPPS and p-ALPPS.METHODS A systematic literature search of PubMed,Embase,the Cochrane Library,and ClinicalTrials.gov was performed for articles published until June 2019.Studies comparing the outcomes of p-ALPPS and ALPPS for a small FLR in consecutive patients were included.Our main endpoints were the morbidity,mortality,and FLR hypertrophy rates.We performed a subgroup analysis to evaluate patients with and without liver cirrhosis.We assessed pooled data using a random-effects model.RESULTS Four studies met the inclusion criteria.Four studies reported data on morbidity and mortality,and two studies reported the FLR hypertrophy rate and one study involved patients with cirrhosis.In the non-cirrhotic group,p-ALPPS-treated patients had significantly lower morbidity and mortality rates than ALPPStreated patients[odds ratio(OR)=0.2;95%confidence interval(CI):0.07–0.57;P=0.003 and OR=0.16;95%CI:0.03-0.9;P=0.04].No significant difference in the FLR hypertrophy rate was observed between the two groups(P>0.05).The total effects indicated no difference in the FLR hypertrophy rate or perioperative morbidity and mortality rates between the ALPPS and p-ALPPS groups.In contrast,ALPPS seemed to have a better outcome in the cirrhotic group.CONCLUSION The findings of our study suggest that p-ALPPS is safer than ALPPS in patients without cirrhosis and exhibits the same rate of FLR hypertrophy. 展开更多
关键词 Liver Cancer PARTIAL split Staged HEPATECTOMY Systematic review Metaanalysis
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内含肽介导的Split-Cre系统的构建 被引量:1
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作者 敖艺菲 张琪 +2 位作者 陈昱僖 黄军就 文锦坤 《生物工程学报》 北大核心 2025年第4期1490-1499,共10页
Split-Cre系统是指被拆分为无活性的N端和C端这2个片段的Cre酶在一定条件下重组为有酶活性的全长Cre的基因工程工具。该系统常结合LoxP元件使用,近年来在多基因操纵、多基因活性标记以及神经环路示踪等方面有着重要的应用。为了开发更... Split-Cre系统是指被拆分为无活性的N端和C端这2个片段的Cre酶在一定条件下重组为有酶活性的全长Cre的基因工程工具。该系统常结合LoxP元件使用,近年来在多基因操纵、多基因活性标记以及神经环路示踪等方面有着重要的应用。为了开发更高效的Split-Cre系统,本研究利用海洋红嗜热盐菌(Rhodothermus marinus,Rma)内含肽对Cre进行拆分,在“红绿灯”报告细胞系中筛选出了能够高效介导Cre酶重组的S102拆分位点,并且通过双腺相关病毒(adeno-associatedvirus,AAV)将S102 Split-Cre系统递送至小鼠体内,证明了Rma内含肽介导的S102 Split-Cre系统在小鼠体内同样具有高效的活性。本研究为Split-Cre的基础和应用研究提供了可靠的参考。 展开更多
关键词 Cre酶 split-Cre系统 海洋红嗜热盐菌内含肽 断裂内含肽
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Complete splitting process of steel fiber reinforced concrete at intermediate strain rate 被引量:1
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作者 罗章 李夕兵 赵伏军 《Journal of Central South University of Technology》 EI 2008年第4期569-573,共5页
The complete splitting process of steel fiber reinforced concrete (SFRC) at intermediate strain rate was studied by experiment. The basic information of a self-developed SFRC dynamic test system matching with lnstro... The complete splitting process of steel fiber reinforced concrete (SFRC) at intermediate strain rate was studied by experiment. The basic information of a self-developed SFRC dynamic test system matching with lnstron 1342 materials testing machine was given, and the experiment principle and the loading mode of cubic split specimen were introduced. During the experiment, 30 cubes of 150 mm×150 mm×150 mm and 36 cubes of 100 mm×100 mm×100 mm, designed and prepared according to C20 class SFRC with different volume fractions of steel fiber (0, 1%, 2%, 3%, 4%) were tested and analyzed. At the same time, the size effect of SFRC at intermediate strain rate was investigated. The experimental study indicates that SFRC size effect is not influenced by the loading speed or strain rate. When the steel fiber content increases from 0 to 4%, the splitting strength of SFRC increases from 100% to 261%, i.e. increasing by 161% compared with that of the common concrete. The loading rate increases from 1.33 kN/s to 80.00 kN/s, and the splitting tensile strength increases by 43.55%. 展开更多
关键词 steel fiber reinforced concrete intermediate strain rate splitting test size effect
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Comparative analysis of energy-level splitting of Pr^(3+) doped in LiYF_4 and LiBiF_4 crystals:a complete energy matrix calculation
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作者 段美玲 邝小渝 +1 位作者 张彩霞 柴瑞鹏 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第1期296-303,共8页
Based on the combination of Racah's group-theoretical consideration with Slater's wavefunction, a 91 ×91 complete energy matrix is established in tetragonal ligand field D2d for Pr3+ ion. Thus, the Stark energ... Based on the combination of Racah's group-theoretical consideration with Slater's wavefunction, a 91 ×91 complete energy matrix is established in tetragonal ligand field D2d for Pr3+ ion. Thus, the Stark energy-levels of Pr3+ ions doped separately in LiYF4 and LiBiF4 crystals are calculated, and our calculations imply that the complete energy matrix method can be used as an effective tool to calculate the energy-levels of the systems doped by rare earth ions. Besides, the influence of Pr3+ on energy-level splitting is investigated, and the similarities and the differences between the two doped crystals are demonstrated in detail by comparing their several pairs of curves and crystal field strength quantities. We see that the energy splitting patterns are similar and the crystal field interaction of LiYF4:Pr3+ is stronger than that of LiBiF4:Pr3+. 展开更多
关键词 energy levels splitting rare earth ions complete energy matrix
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Bimetallic Single‑Atom Catalysts for Water Splitting 被引量:1
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作者 Megha A.Deshmukh Aristides Bakandritsos Radek Zbořil 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期1-45,共45页
Green hydrogen from water splitting has emerged as a critical energy vector with the potential to spearhead the global transition to a fossil fuel-independent society.The field of catalysis has been revolutionized by ... Green hydrogen from water splitting has emerged as a critical energy vector with the potential to spearhead the global transition to a fossil fuel-independent society.The field of catalysis has been revolutionized by single-atom catalysts(SACs),which exhibit unique and intricate interactions between atomically dispersed metal atoms and their supports.Recently,bimetallic SACs(bimSACs)have garnered significant attention for leveraging the synergistic functions of two metal ions coordinated on appropriately designed supports.BimSACs offer an avenue for rich metal–metal and metal–support cooperativity,potentially addressing current limitations of SACs in effectively furnishing transformations which involve synchronous proton–electron exchanges,substrate activation with reversible redox cycles,simultaneous multi-electron transfer,regulation of spin states,tuning of electronic properties,and cyclic transition states with low activation energies.This review aims to encapsulate the growing advancements in bimSACs,with an emphasis on their pivotal role in hydrogen generation via water splitting.We subsequently delve into advanced experimental methodologies for the elaborate characterization of SACs,elucidate their electronic properties,and discuss their local coordination environment.Overall,we present comprehensive discussion on the deployment of bimSACs in both hydrogen evolution reaction and oxygen evolution reaction,the two half-reactions of the water electrolysis process. 展开更多
关键词 Single-atom catalysts Single-atom dimers Hydrogen evolution Oxygen evolution Water splitting
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On the Existence of (v,3×3,λ)-Splitting Balanced Incomplete Block Design with λ between 2 to 9
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作者 苏仁旺 王金华 《Journal of Shanghai Jiaotong university(Science)》 EI 2008年第4期482-486,共5页
Let (v, u × c,λ)-splitting BIBD denote a (v, u × c,λ)-splitting balanced incomplete block design of order v with block size u × c and index A. The necessary conditions for the existence of a (v, ... Let (v, u × c,λ)-splitting BIBD denote a (v, u × c,λ)-splitting balanced incomplete block design of order v with block size u × c and index A. The necessary conditions for the existence of a (v, u × c,λ)-splitting BIBD are v ≥ uc, λ(v- 1) -- 0 0 mod (c(u- 1)) and Av(v- 1) - 0 mod (c^2u(u- 1)). In this paper, for 2 ≤λ≤ 9 the necessary conditions for the existence of a (v, 3 × 3, λ)-splitting BIBD are also sufficient with one possible exception for (v, λ) = (39, 9). 展开更多
关键词 splitTING balanced incomplete block design group-divisible design (GDD)
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Splitting Balanced Incomplete Block Designs with Block Size 2×k
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作者 沈军 《Journal of Shanghai Jiaotong university(Science)》 EI 2005年第1期103-106,共4页
This paper investigated the existence of splitting balanced incomplete block designs with blck size 2× k .The necessary conditions for such a design are λ(v-1) ≡0(mod k ),and λv(v- 1)≡0(mod 2 k 2).It will sho... This paper investigated the existence of splitting balanced incomplete block designs with blck size 2× k .The necessary conditions for such a design are λ(v-1) ≡0(mod k ),and λv(v- 1)≡0(mod 2 k 2).It will show that the above necessary conditions are also sufficient for k =3 with the definite exception( v,λ )=(10,1) and with several possible exceptions. 展开更多
关键词 balanced incomplete block designs(BIBD) splitting BIBD
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Passive activity enhances residual control ability in patients with complete spinal cord injury 被引量:2
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作者 Yanqing Xiao Mingming Gao +6 位作者 Zejia He Jia Zheng Hongming Bai Jia-Sheng Rao Guiyun Song Wei Song Xiaoguang Li 《Neural Regeneration Research》 SCIE CAS 2025年第8期2337-2347,共11页
Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury level.However,because of prolonged inactivity,initial attempts to activate these... Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury level.However,because of prolonged inactivity,initial attempts to activate these muscles may not effectively engage any of the remaining neurons in the descending pathway.A previous study unexpectedly found that a brief clinical round of passive activity significantly increased volitional muscle activation,as measured by surface electromyography.In this study,we further explored the effect of passive activity on surface electromyographic signals during volitional control tasks among individuals with complete spinal cord injury.Eleven patients with chronic complete thoracic spinal cord injury were recruited.Surface electromyography data from eight major leg muscles were acquired and compared before and after the passive activity protocol.The results indicated that the passive activity led to an increased number of activated volitional muscles and an increased frequency of activation.Although the cumulative root mean square of surface electromyography amplitude for volitional control of movement showed a slight increase after passive activity,the difference was not statistically significant.These findings suggest that brief passive activity may enhance the ability to initiate volitional muscle activity during surface electromyography tasks and underscore the potential of passive activity for improving residual motor control among patients with motor complete spinal cord injury. 展开更多
关键词 complete spinal cord injury cycle training epidural electrical stimulation motor training passive activity physiological state spinal cord circuit surface electromyography volitional control task
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Single-atom Ru-doped nickel sulfide nanostructures achieve superior water splitting performance via reconstruction and adsorption optimization
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作者 Rongfang Li Bowen Guo +6 位作者 Zongkun Bian Jin Chang Jiaxin Zhang Jiayue Wang Heng Zhang Wenqiang Li Xun Feng 《Journal of Materials Science & Technology》 2025年第35期313-321,共9页
The strategic design of single-atom catalysts and a detailed understanding of the synergistic interactions between metal sites and substrates are crucial for identifying the true active sites and elucidating cat-alyti... The strategic design of single-atom catalysts and a detailed understanding of the synergistic interactions between metal sites and substrates are crucial for identifying the true active sites and elucidating cat-alytic mechanisms at the atomic level.These insights are essential for advancing the development of high-performance catalysts for various industrial applications.Ruthenium single-atom-doped nickel sul-fide(Ru-Ni_(3)S_(2)/NF)nanosheet arrays were purposefully engineered and directly synthesized onto nickel foam,enabling dynamic catalyst reconstruction and establishing a robust three-dimensional structure,in this study.The catalyst exhibits exceptional performance,achieving a current density of 10 mA cm^(-2) with remarkably low overpotentials of 36 mV for hydrogen evolution reaction(HER)and 207 mV for oxygen evolution reaction(OER).Additionally,a custom-designed anion exchange membrane water electrolyzer(AEMWE)utilizing Ru-Ni_(3)S_(2)/NF as both the anode and cathode demonstrates superior water splitting performance,achieving a cell voltage of 1.67 V at a current density of 1 A cm^(-2).Theoretical analysis re-veals that Ru-Ni_(3)S_(2) undergoes rapid structural reconstruction during the OER process,forming a highly active Ru-Ni_(3)S_(2)/NiOOH phase,optimizing the adsorption and dissociation of water molecules,which sig-nificantly enhances kinetics.This work provided a promising reconstruction strategy to improve catalytic performance by combining low-cost sulfide materials with single-atom dispersing.It also offers valuable insights for the design of advanced electrocatalysts aimed at achieving high-performance water electrol-ysis. 展开更多
关键词 Nickel sulfide Hydrogen evolution reaction Catalyst reconstruction Oxygen evolution complete water splitting Theoretical calculations
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