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A Hybrid Experimental-Numerical Framework for Identifying Viscoelastic Parameters of 3D-Printed Polyurethane Samples:Cyclic Tests,Creep/Relaxation and Inverse Finite Element Analysis
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作者 Nikita Golovkin Olesya Nikulenkova +4 位作者 Vsevolod Pobezhimov Alexander Nesmelov Sergei Chvalun Fedor Sorokin Arthur Krupnin 《Computers, Materials & Continua》 2026年第3期519-536,共18页
This study presents and verifies a hybrid methodology for reliable determination of parameters in structural rheological models(Zener,Burgers,and Maxwell)describing the viscoelastic behavior of polyurethane specimens ... This study presents and verifies a hybrid methodology for reliable determination of parameters in structural rheological models(Zener,Burgers,and Maxwell)describing the viscoelastic behavior of polyurethane specimens manufactured using extrusion-based 3D printing.Through comprehensive testing,including cyclic compression at strain rates ranging from 0.12 to 120 mm/min(0%-15%strain)and creep/relaxation experiments(10%-30%strain),the lumped parameters were independently determined using both analytical and numerical solutions of the models’differential equations,followed by cross-verification in additional experiments.Numerical solutions for creep and relaxation problems were obtained using finite element analysis,with the three-parameter Mooney-Rivlin model and Prony series employed to simulate elastic and viscous stress components,respectively.Energy dissipation per cycle was quantified during cyclic compression tests.The results demonstrate that all three models adequately describe material behavior within the 0%-15%strain range across various strain rates.Comparative analysis revealed the Burgers model’s superior performance in characterizing creep and stress relaxation at low strain levels.While Zener and Burgers model parameters from uniaxial compression showed limited applicability for energy dissipation calculations,the generalized Maxwell model effectively captured viscoelastic properties across different strain rates.Notably,parameters derived from creep tests provided a more universal assessment of dissipative properties due to optimization based on characteristic curve regions.Both parameter sets described polyurethane’s elastic-hysteretic behavior with approximately 20%error,proving significantly more accurate than the linear strain-time dependence hypothesis.Finite element analysis(FEA)complemented numerical modeling by demonstrating that while the generalized Maxwell model effectively describes initial rapid stress-strain changes,FEA provides superior characterization of steady-state processes.This computational approach yields more physically representative results compared to simplified analytical solutions,despite certain limitations in transient analysis. 展开更多
关键词 VISCOELASTICITY cyclic compression HYSTERESIS CREEP stress relaxation finite element method optimization 3D printing structural rheological models Prony series
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Prelithiation of silicon encapsulated in MOF-derived carbon/ZnO framework for high-performance lithium-ion battery
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作者 Congcong Liu Yang Yang +6 位作者 Yu Yao Tao Dai Shitan Xu Shoumeng Yang Ghulam Ali Xianhong Rui Yan Yu 《Nano Materials Science》 2026年第2期298-306,共9页
Silicon possesses a high theoretical capacity,making it a potential contender for lithium-ion battery(LIB)anodes.Nonetheless,its practical usage is challenged by low electrical conductivity and significant volume expa... Silicon possesses a high theoretical capacity,making it a potential contender for lithium-ion battery(LIB)anodes.Nonetheless,its practical usage is challenged by low electrical conductivity and significant volume expansion during cycling.Here,we synthesized a novel silicon/carbon(Si/C)anode doped with ZnO via a template-derived method and high-temperature carbonization.The carbon structure,originated from metal-organic frameworks(MOFs)and ZnO doping,substantially enhanced the electrochemical properties of the composite material.It exhibited an initial capacity of 2100.3 mA h g^(-1)at a current density of 0.2 A g^(-1)and demonstrated excellent capacity retention over successive cycles.Moreover,the composite material displayed superior rate performance at higher current densities of 2 A g^(-1)and 3 A g^(-1).To address the low initial Coulombic efficiency(ICE)of siliconbased materials,we adopted a direct contact prelithiation approach and optimized the lithiation process by controlling the prelithiation time.After 30 min of prelithiation,the ICE reached 97.9%,thereby reducing the initial irreversible capacity loss(ICL)and realizing stable discharge-charge in subsequent cycles.This rational design provides valuable insights for achieving high-performance silicon anode. 展开更多
关键词 Metal-organic frameworks SILICON ZNO Prelithiation Lithium-ion batteries
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Non-Markovian dynamical solver for efficient combinatorial optimization
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作者 Haijie Xu Zhe Yuan 《Chinese Physics B》 2026年第2期583-590,共8页
We incorporate a non-Markovian feedback mechanism into the simulated bifurcation method for dynamical solvers addressing combinatorial optimization problems.By reinjecting a portion of dissipated kinetic energy into e... We incorporate a non-Markovian feedback mechanism into the simulated bifurcation method for dynamical solvers addressing combinatorial optimization problems.By reinjecting a portion of dissipated kinetic energy into each spin in a history-dependent and trajectory-informed manner,the method effectively suppresses early freezing induced by inelastic boundaries and enhances the system's ability to explore complex energy landscapes.Numerical results on the maximum cut(MAX-CUT)instances of fully connected Sherrington–Kirkpatrick(SK)spin glass models,including the 2000-spin K_(2000)benchmark,demonstrate that the non-Markovian algorithm significantly improves both solution quality and convergence speed.Tests on randomly generated SK instances with 100 to 1000 spins further indicate favorable scalability and substantial gains in computational efficiency.Moreover,the proposed scheme is well suited for massively parallel hardware implementations,such as field-programmable gate arrays,providing a practical and scalable approach for solving large-scale combinatorial optimization problems. 展开更多
关键词 non-Markovian dynamics simulated bifurcation combinatorial optimization maximum cut(MAX-CUT)problem spin glass
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Effect of fluorination positions at diphenylamino flanking groups on the photovoltaic performance for nonfused ring electron acceptors
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作者 Yang Gao Huarui Zhang +7 位作者 Yan Xie Xinjun Xu Yahui Liu Hao Lu Wenkai Zhang Yuqiang Liu Cuihong Li Zhishan Bo 《Chinese Chemical Letters》 2026年第1期368-373,共6页
The fluorination strategy has been proven effective in significantly enhancing the photovoltaic performance of organic solar cells(OSCs) based on non-fused ring electron acceptors(NFREAs).However,research on the impac... The fluorination strategy has been proven effective in significantly enhancing the photovoltaic performance of organic solar cells(OSCs) based on non-fused ring electron acceptors(NFREAs).However,research on the impact of fluorination positions at side chains on NFREAs device performance remains scant.In this study,we introduce two isomeric NFREAs,designated as GA-2F-E and GA-2F,distinguished by their fluorination positions at the side chains.Both NFREAs share a thiophene[3,2-b]thiophene core,but their side chains differ:GA-2F-E features two(4-butylphenyl)-N-(4-fluorophenyl) amino groups,whereas GA-2F's side chains consist of bis(4-fluorophenyl)amino and bis(4-butylphenyl)amino groups attached to opposite sides of the core.To delve into the influence of fluorination positions on the optoelectronic properties,aggregation behavior,and overall efficiency of the acceptor molecules,a comprehensive investigation was conducted.The findings reveal that,despite similar photophysical properties and comparable absorption bandwidths,GA-2F-E,with fluorine atoms positioned on both sides of the molecular framework,demonstrates more compact π-π stacking,reduced bimolecular recombination,superior exciton transport,and a more balanced,higher mobility.As a result of these advantages,OSCs optimized with D18:GA-2F-E achieve a remarkable power conversion efficiency(PCE) of 16.45 %,surpassing the 15.83 %PCE of devices utilizing D18:GA-2F.This research underscores the potential of NFREAs in future applications and highlights the significance of fluorination positions in enhancing OSC performance,paving the way for the development of more efficient NFREAs. 展开更多
关键词 Organic solar cells Non-fused ring electron acceptors Fluorination position Diphenylamino groups Power conversion efficiencies
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Synergistic Fe–Si Dual-Site Pathway Engineering in Biomass-Derived Carbon Matrix for High-Performance Oxygen Reduction Reaction
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作者 Min Su Cho Yanmei Zang +12 位作者 Sung Joon Park Byeong‐Seon An Ho Jin Lee Ashishi Gaur Ghulam Ali Mingony Kim Kyung Yoon Chung Sungbin Park Yung‐Eun Sung Daehae Kim Ki Jae Kim Chang Woo Myung HyukSu Han 《Carbon Energy》 2026年第3期55-67,共13页
Anion exchange membrane fuel cells(AEMFCs) offer a sustainable energy solution with non-precious metal catalysts,reduced degradation,and fuel flexibility.However,the sluggish oxygen reduction reaction(ORR) at the cath... Anion exchange membrane fuel cells(AEMFCs) offer a sustainable energy solution with non-precious metal catalysts,reduced degradation,and fuel flexibility.However,the sluggish oxygen reduction reaction(ORR) at the cathode and durability concerns impede commercialization.To address these challenges,this study presents a dual-atomic SiFe-N-C catalyst derived from pinecones,a naturally abundant biomass resource.The catalyst features a nitrogen-rich porous carbon matrix that stabilizes Si-Fe dual-atomic sites during pyrolysis.Advanced analyses confirm Fe-Si and Fe-N bonds,which synergistically enhance ORR activity by optimizing electronic structures and intermediate adsorption energies.The SiFe-N-C catalyst surpasses Pt/C and Fe-N-C single-atom benchmarks with superior ORR activity and excellent long-term durability supported by high resistance to CO poisoning as well as methanol crossover.It also demonstrates a promising electrochemical performance as a catalytic material for the separator of Li-S battery.Mechanistic studies reveal that the Si-Fe dual-atomic configuration promotes an efficient Fe-O-O-Si pathway,reducing energy barriers and offering a cost-effective,high-performance solution for electrochemical energy conversion and storage applications. 展开更多
关键词 carbon ELECTROCATALYSIS energy storage and conversion fuel cells heterocatalysis NANOMATERIALS
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Modeling the chondrocyte-derived osteoblasts formation process reveals its molecular signature and regulation network
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作者 Raquel Ruiz-Hernández Laurie Gay +21 位作者 Verónica Moncho-Amor Pablo Martín Jhonatan A.Vergara-Arce Stefania Di Blasio Thomas Snoeks Unai Cossío Ander Matheu Maria M.Caffarel Daniela Gerovska Marcos J.Araúzo-Bravo Amaia Vilas Felipe Prosper Sergio Moya Daniel Alonso-Alconada Ana Alonso-Varona Gretel Nusspaumer Javier Lopez-Rios Karine Rizotti Robin Lovell-Badge Dominique Bonnet Ilaria Malanchi Ander Abarrategi 《Bone Research》 2026年第1期291-302,共12页
Endochondral ossification is a physiological process involving a sequential formation of cartilage and bone tissues.Classically,cartilage and bone formation have been considered independent processes at cellular level... Endochondral ossification is a physiological process involving a sequential formation of cartilage and bone tissues.Classically,cartilage and bone formation have been considered independent processes at cellular level.However,the recently described multiple cell differentiation dynamics suggest that some bone cells are indeed the progeny of cartilage cells,or chondrocyte-derived osteoblasts.We hypothesized that the cartilage-to-bone phenotype transition is triggered by specific molecular events.First,the process was assessed in mouse bone tissue,and then,it was mimicked using in vivo cell implantation and in vitro serial differentiation protocols.Data indicates that cartilage cells transition to bone cell phenotype during postnatal physiological bone formation.This process can be reproduced using cartilage precursor cells coupled to specific implantation procedures or differentiation protocols.Gene expression profiling reveals that NOTCH,BMP and MAPK signaling pathways are relevant at the phenotype-switch,while the transcription factors Mesp1,Alx1,Grhl3 and Hmx3 are the feasible driver genes for chondrocyte-derived osteoblasts formation.Altogether,this report shows that endochondral ossification can be modeled using primary cell cultures and data indicate that this process is regulated by specific molecular events,previously described at skeleton morphogenesis during embryo development,and from now on also linkable to postnatal bone development and regeneration processes. 展开更多
关键词 regulation network postnatal bone development chondrocyte derived osteoblasts multiple cell differentiation dynamics molecular signature bone tissuesclassicallycartilage bone cells endochondral ossification
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Multifunctional Janus-Structured Polytetrafluoroethylene-Carbon Nanotube-Fe_(3)O_(4)/MXene Membranes for Enhanced EMI Shielding and Thermal Management 被引量:1
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作者 Runze Shao Guilong Wang +4 位作者 Jialong Chai Jun Lin Guoqun Zhao Zhihui Zeng Guizhen Wang 《Nano-Micro Letters》 2025年第6期242-263,共22页
Herein,a novel Janus-structured multifunctional membrane with integrated electromagnetic interference(EMI)shielding and personalized thermal management is fabricated using shear-induced in situ fibrillation and vacuum... Herein,a novel Janus-structured multifunctional membrane with integrated electromagnetic interference(EMI)shielding and personalized thermal management is fabricated using shear-induced in situ fibrillation and vacuum-assisted filtration.Interestingly,within the polytetrafluoroethylene(PTFE)-carbon nanotube(CNT)-Fe_(3)O_(4)layer(FCFe),CNT nanofibers interweave with PTFE fibers to form a stable“silk-like”structure that effectively captures Fe_(3)O_(4)particles.By incorporating a highly conductive MXene layer,the FCFe/MXene(FCFe/M)membrane exhibits excellent electrical/thermal conductivity,mechanical properties,and flame retardancy.Impressively,benefiting from the rational regulation of component proportions and the design of a Janus structure,the FCFe/M membrane with a thickness of only 84.9μm delivers outstanding EMI shielding effectiveness of 44.56 dB in the X-band,with a normalized specific SE reaching 10,421.3 dB cm^(2)g^(-1),which is attributed to the“absorption-reflection-reabsorption”mechanism.Furthermore,the membrane demonstrates low-voltage-driven Joule heating and fast-response photothermal performance.Under the stimulation of a 3 V voltage and an optical power density of 320 mW cm^(-2),the surface temperatures of the FCFe/M membranes can reach up to 140.4 and 145.7℃,respectively.In brief,the FCFe/M membrane with anti-electromagnetic radiation and temperature regulation is an attractive candidate for the next generation of wearable electronics,EMI compatibility,visual heating,thermotherapy,and military and aerospace applications. 展开更多
关键词 MXene Polytetrafluoroethylene Fe_(3)O_(4) Janus-structured EMI shielding Thermal management MULTIFUNCTIONAL
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In-situ growth of cross-link NiAl-LDH nanosheets on the inner/outer surfaces of carbon microtubes for anti-corrosive electromagnetic wave absorption
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作者 Rui Liu Xiao Liu +7 位作者 Lihong Wu Changlong Du Haiming Lv Gengping Wan Hualin Xiong Xiang Yuan Jieping Wang Guizhen Wang 《Journal of Materials Science & Technology》 2025年第35期109-118,共10页
Electromagnetic wave(EMW)absorbers with anti-corrosion property are highly desired to enhance the durability of military targets in harsh condition.Herein,cross-link NiAl-layered double hydroxide(NiAl-LDH)nanosheets o... Electromagnetic wave(EMW)absorbers with anti-corrosion property are highly desired to enhance the durability of military targets in harsh condition.Herein,cross-link NiAl-layered double hydroxide(NiAl-LDH)nanosheets on the inner/outer surfaces of carbon microtubes(CMTs)are ingeniously constructed through the combination of atomic layer deposition technique and a hydrothermal method.The obtained NiAl-LDH/CMT composite exhibits excellent EMW absorption and corrosion resistance performance.The large internal cavity of CMT significantly enhances impedance matching.The uniform distribution of NiAl-LDH nanosheets on both the inner and outer surfaces of CMT generates numerous heterogeneous inter-faces that induce substantial polarization loss.Consequently,at a filler rate of only 5 wt.%,the NiAl-LDH/CMT composite exhibits a minimum reflection loss of−60.2 dB and a maximum effective absorp-tion bandwidth of 5.9 GHz.In addition,the combined high impermeability of CMT and the effective Cl^(-)-trapping ability of NiAl-LDH endows NiAl-LDH/CMT composite with outstanding corrosion protection property in simulated seawater environment.Furthermore,the PO_(4)^(3-)anions are effectively incorporated into the NiAl-LDH interlayer via anion exchange,which can further enhance corrosion protection capac-ity through surface inactivation from slow-release PO_(4)^(3-)anions without reducing their EMW absorption performance.In summary,this work can give guidance for the development of efficient anti-corrosion EMW absorption materials. 展开更多
关键词 Carbon microtubes NiAl-LDH Electromagnetic wave absorption materials Anti-corrosion property
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Measuring Reaction Rates for Heterogeneous Catalysis
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作者 Jiamei Quan Alec M.Wodtke 《Chinese Journal of Chemical Physics》 2025年第6期729-749,I0237,共22页
Heterogeneous catalysis on solid surfaces provides high-value chemicals and is involved in a large fraction of the world’s economic productivity,yet our understanding of this important class of processes remains limi... Heterogeneous catalysis on solid surfaces provides high-value chemicals and is involved in a large fraction of the world’s economic productivity,yet our understanding of this important class of processes remains limited.Thermal reaction rates obtained from experiments on mod-el catalysts provide quantitative data that can reveal reaction mechanisms and provide benchmarks for computational simulations of catalytic processes.This perspective describes a critical advance in measuring these rates:velocity resolved kinetics(VRK).VRK delivers ab-solute rates for elementary surface reactions that are of sufficient accuracy that they may be meaningfully compared to theoretical rate predictions,creating a powerful synergy between theory and experiment.It is now routinely possible to derive fundamental thermochemical quantities,including desorption and adsorption energies,reaction barrier heights,diffusion barrier heights,and lateral adsorbate interaction energies.Reaction mechanisms can also be revealed and reaction intermediates directly detected.The high time resolution of VRK al-lows study of catalytic reactions at the high temperatures typical of conditions present in real catalytic reactors.Current work exploiting the newest and by far the most powerful variant of VRK has only scratched the surface of what is possible,signifying a promising future for re-searchers in this field. 展开更多
关键词 Velocity resolved kinetics Molecular beams Reaction energies Barrier heights
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Reimagining tourism pedestrian street aesthetics through machine learning:Understanding the role of spatial form based on a case study in Luoyang,China
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作者 Xin Gao Hirofumi Ueda +3 位作者 Meng Qu Guang Li Xiaojin Li Menglin Xu 《Frontiers of Architectural Research》 2026年第1期238-258,共21页
Pedestrian streets are vital for urban livability,tourism,and cultural identity.This research examines how human-perspective spatial form influences aesthetic perception,using a tourist street in central Luoyang as a ... Pedestrian streets are vital for urban livability,tourism,and cultural identity.This research examines how human-perspective spatial form influences aesthetic perception,using a tourist street in central Luoyang as a case site.Based on perceptual evaluations from participants in Luoyang and Xi'an,the research isolates key structural elements and reveals the underlying relationship between spatial form and tourist aesthetic preferences.Deep learning models were used to extract spatial indicators from real-world streetscapes,aligning them with abstracted representations.Modelling the extracted indicators with a Generalized Additive Model(GAM),the study enables large-scale analysis and captures both individual spatial characteristics and their interactive effects on aesthetic perception.This approach not only models complex nonlinear relationships but also provides a solid foundation for aesthetic prediction and assessment.The findings identify the proportion of sky(PS),ground area(PG),and spatial depth(D)as key factors influencing aesthetic judgments,while the proportion of vertical elements(PV)and the ground-to-vertical ratio(G/V)show high multicollinearity.Additionally,street-level average aesthetics tend to be rated higher than point-wise average aesthetics.These insights allow for the layout and adjustment of spatial form by balancing the aesthetic preferences of local and non-local visitors,ultimately enhancing pedestrian street aesthetics. 展开更多
关键词 Street spatial form Aesthetic perception Tourism street Machine learning Aesthetic evaluation
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Pressure-Enhanced Intrinsic Anomalous Hall Conductivity in the Kagome Ferrimagnet TbMn_(6)Sn_(6)
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作者 Hao Sun Jiabin Qiao +13 位作者 Weian Guo Pengyu Zheng Yuwei Liu Pengda Ye Yuemei Li Shucui Sun Deng Hu Yongkai Li Yanpeng Qi Zhiwei Wang Meiling Jin Jie Chen Zhiping Yin Xiang Li 《Chinese Physics Letters》 2026年第3期102-117,共16页
The kagome ferrimagnet TbMn_(6)Sn_(6),featuring a pristine Mn kagome lattice,has emerged as a candidate Chern magnet with a large intrinsic anomalous Hall effect(AHE).While chemical substitution can modulate its prope... The kagome ferrimagnet TbMn_(6)Sn_(6),featuring a pristine Mn kagome lattice,has emerged as a candidate Chern magnet with a large intrinsic anomalous Hall effect(AHE).While chemical substitution can modulate its properties,hydrostatic pressure provides a disorder-free route to manipulate electronic and magnetic interactions.Herein,we investigate the effects of hydrostatic pressure on electrical and magneto-transport in TbMn6Sn6 up to 18.3 GPa.Pressure significantly enhances hysteresis in the magnetoresistance and Hall responses,causing a concurrent monotonic coercive field increase,suggesting the enhancement of interlayer magnetic couplings in a robust c-axis ferrimagnetic order.The intrinsic anomalous Hall conductivity increases considerably from 129.5 S·cm^(−1) at ambient pressure conditions to 448.7 S·cm^(−1) at 14.0 GPa—an enhancement of 247%that is unprecedented among pressure-tuned kagome magnets.Based on density functional theory calculations,we reveal that pressure induces multiple gap openings near the Fermi level,giving rise to pronounced Berry curvature hotspots that may contribute to the AHE.Our results show that pressure can be used to enhance the intrinsic topological responses of this kagome magnet. 展开更多
关键词 chern magnet mn kagome latticehas anomalous hall effect ahe enhances hysteresis magnetoresistance kagome ferrimagnet chemical substitution hydrostatic pressure manipulate electronic magnetic interactionshereinwe
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One step NaBH_4 reduction of Pt-Ru-Ni catalysts on different types of carbon supports for direct ethanol fuel cells : Synthe sis and characte rization 被引量:4
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作者 Napha Sudachom Chompunuch Warakulwit +2 位作者 Chaiwat Prapainainar Thongthai Witoon Paweena Prapainainar 《燃料化学学报》 EI CAS CSCD 北大核心 2017年第5期596-607,共12页
The ternary catalyst Pt75Ru5Ni20 was conducted on various types of carbon supports including functionalized Vulcan XC-72R(f-CB),functionalized multi-walled carbon nanotubes(f-MWCNT),and mesoporous carbon(PC-Zn-succini... The ternary catalyst Pt75Ru5Ni20 was conducted on various types of carbon supports including functionalized Vulcan XC-72R(f-CB),functionalized multi-walled carbon nanotubes(f-MWCNT),and mesoporous carbon(PC-Zn-succinic)by sodium borohydride chemical reduction method to improve the ethanol electrooxidation reaction(EOR)for direct ethanol fuel cell(DEFC).It was found that the particle size of the metals on f-MWCNT was 5.20 nm with good particle dispersion.The alloy formation of ternary catalyst was confirmed by XRD and more clearly described by SEM element mapping,which was relevant to the efficiency of the catalysts.Moreover,the mechanism of ethanol electrooxidation reaction based on the surface reaction was more understanding.The activity and stability for ethanol electrooxidation reaction(EOR)were investigated using cyclic voltammetry and chronoamperometry,respectively.The highest activity and stability for EOR were observed from Pt75Ru5Ni20/f-MWCNT due to a good metal-carbon interaction.Ru and Ni presented in Pt-Ru-Ni alloy improved the activity and stability of ternary catalysts for EOR.Moreover,the reduction of Pt content in ternary catalyst led to the catalyst cost deduction in DEFC. 展开更多
关键词 ternary catalyst ethanol electrooxidation reaction multiwall carbon nanotubes mesoporous carbon
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MicroRNA: a new and promising potential biomarker for diagnosis and prognosis of ovarian cancer 被引量:12
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作者 Manish K.Pal Shyam P.Jaiswar +3 位作者 Vinaya N.Dwivedi Amit K.Tripathi Ashish Dwivedi Pushplata Sankhwar 《Cancer Biology & Medicine》 SCIE CAS CSCD 2015年第4期328-341,共14页
Epithelial ovarian cancer(EOC) is the leading cause of death among all gynecological malignancies. Despite the technological and medical advances over the past four decades, such as the development of several biologic... Epithelial ovarian cancer(EOC) is the leading cause of death among all gynecological malignancies. Despite the technological and medical advances over the past four decades, such as the development of several biological markers(mRNA and proteins biomarkers), the mortality rate of ovarian cancer remains a challenge because of its late diagnosis, which is specifically attributed to low specificities and sensitivities. Under this compulsive scenario, recent advances in expression biology have shifted in identifying and developing specific and sensitive biomarkers, such as micro RNAs(miRNAs) for cancer diagnosis and prognosis. MiRNAs are a novel class of small non-coding RNAs that deregulate gene expression at the posttranscriptional level, either by translational repression or by mRNA degradation. These mechanisms may be involved in a complex cascade of cellular events associated with the pathophysiology of many types of cancer. MiRNAs are easily detectable in tissue and blood samples of cancer patients. Therefore, miRNAs hold good promise as potential biomarkers in ovarian cancer. In this review, we attempted to provide a comprehensive profile of key miRNAs involved in ovarian carcinoma to establish mi RNAs as more reliable non-invasive clinical biomarkers for early detection of ovarian cancer compared with protein and DNA biomarkers. 展开更多
关键词 Micro RNAs(miRNA) biomarker chemoresistance detection RT-PCR
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Spatial and temporal dynamics of Pai forest vegetation in Pakistan assessed by RS and GIS 被引量:1
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作者 A.A.Siyal A.G.Siyal R.B.Mahar 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第3期593-603,共11页
Pai, an arid forest in Sindh Province of Pakistan, is important for the environmental, social, economic development and conservation of ecosystems of the province. Considering the significance of the forest for Sindh ... Pai, an arid forest in Sindh Province of Pakistan, is important for the environmental, social, economic development and conservation of ecosystems of the province. Considering the significance of the forest for Sindh and the calls from the local population for its deforestation, we quantified the spatial and temporal variation in the vegetation of the forest and land surface temperature (LST) using optical and thermal Landsat satellite data. Our analysis of temporal (1987-2014) images with ArcGIS 10.1 revealed that the dense forest area was greatest at 725 ha (37 % of the total forest area) during 2013 while it was smallest at 217 ha (11%) in 1992. The sparse forest area peaked during 1987 at 1115 ha (58 %) under shrubs whereas it was smallest at 840 ha (43 %) in 1992, and the maximum deforestation of Pai forest occurred during 1992. Spatial change in vegetation over a period of about 27 years (1987-2014) revealed that vegetation increased on an area of 735 ha (37 %), decreased on 427 ha (22 %), and there was no change on 808 ha (41%) of the forest. Variation in temperature between shaded (dense forest) and unshaded areas (bare land) of the forest was from 6 to 10 ℃. While the temperature difference between areas with sparse forest and bare land ranged from 4 to 6℃. An inverse relationship between LST and NDVI of Pai forest with coefficients of determination of 0.944 and 0.917 was observed when NDVI was plotted against minimum and maximum LST, respectively. The vegetation in the forest increased with time and the areas of more dense Pai forest supported lower surface temperature and thus air temperature. 展开更多
关键词 LANDSAT Arid forest NDVI DEFORESTATION ECOSYSTEM Land surface temperature (LST)
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Modification of mechanical properties by TiO_2 nano-particle for biodegradable materials made from palm oil sludge and activated sludge cake 被引量:1
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作者 Panithi YUTHAVISUTHI Lerpong JARUPAN Chiravoot PECHYEN 《中国有色金属学会会刊:英文版》 CSCD 2012年第S3期697-701,共5页
Titanium dioxide (TiO2) nano-particle is widely used in composite materials to its improved mechanical properties.TiO2 nano-particle was used in the composite material that consists of palm oil sludge from the palm oi... Titanium dioxide (TiO2) nano-particle is widely used in composite materials to its improved mechanical properties.TiO2 nano-particle was used in the composite material that consists of palm oil sludge from the palm oil production and activated sludge cake from a papermaking process.TiO2 was synthesized by a hydrolysis of titanium isopropoxide.The parameter was investigated by the mole ratio of reactant to different solvents (isopropanol and isobutanol).The solution was prepared by adjusting pH to acid solution,resulting in different sizes and distributions of precipitate which was heated at different temperatures.The obtained samples were then morphologically and structurally characterized using X-ray diffraction (XRD) and particle size distribution (PSD).The experimental results show that the TiO2 sample from isopropanol solvent with heated temperature of 600 °C exhibits the best results.Consequently,different mass fractions of TiO2 (0,0.5%,1.0%,2.0%,4.0% and 8.0%) were used for specimens that were made from palm oil sludge mixed with activated sludge cake.All samples were later characterized by 3-point bending test and compression test.The results indicate that the adding 0.5% and 1.0% TiO2 particles to the composite material outperforms the other fractions in terms of enhancing mechanical properties.Nonetheless,mechanical properties tends to decrease when adding 2.0% TiO2. 展开更多
关键词 titanium dioxide PALM oil SLUDGE active SLUDGE CAKE composite mechanical properties
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Investigating User Ridership Sentiments for Bike Sharing Programs 被引量:2
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作者 Subasish Das Xiaoduan Sun Anandi Dutta 《Journal of Transportation Technologies》 2015年第2期69-75,共7页
Bike sharing is considered a state-of-the-art transportation program. It is ideal for short or medium trips providing riders the ability to pick up a bike at any self-serve bike station and return it to any bike stati... Bike sharing is considered a state-of-the-art transportation program. It is ideal for short or medium trips providing riders the ability to pick up a bike at any self-serve bike station and return it to any bike station located within the system’s coverage area. The bike sharing programs in the United States are still very young compared to those in European countries. Washington DC was the first jurisdiction to devise a third generation bike sharing system in the US in 2008. To evaluate the popularity of a bike sharing program, a sentiment analysis of the riders’ feedback can be performed. Twitter is a great platform to understand people’s views instantly. Social media mining is, thus, gaining popularity in many research areas including transportation. Social media mining has two major advantages over conventional attitudinal survey methods—it can easily reach a large audience and it can reflect the true behavior of participants because of the anonymity social media provides. It is known that self-imposed censor is common in responding to conversational attitudinal surveys. This study performed text mining on the tweets related to a case study (Capital Bike share of Washington DC) to perform sentiment analysis or opinion mining. The results of the text mining mostly revealed higher positive sentiments towards the current system. 展开更多
关键词 BIKE SHARING Social Media Twitter MINING Text ANALYTIC SENTIMENT Analysis OPINION MINING
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Computer Methodologies for the Comparison of Some Efficient Derivative FreeSimultaneous Iterative Methods for Finding Roots of Non-Linear Equations 被引量:1
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作者 Yuming Chu Naila Rafiq +3 位作者 Mudassir Shams Saima Akram Nazir Ahmad Mir Humaira Kalsoom 《Computers, Materials & Continua》 SCIE EI 2021年第1期275-290,共16页
In this article,we construct the most powerful family of simultaneous iterative method with global convergence behavior among all the existing methods in literature for finding all roots of non-linear equations.Conver... In this article,we construct the most powerful family of simultaneous iterative method with global convergence behavior among all the existing methods in literature for finding all roots of non-linear equations.Convergence analysis proved that the order of convergence of the family of derivative free simultaneous iterative method is nine.Our main aim is to check out the most regularly used simultaneous iterative methods for finding all roots of non-linear equations by studying their dynamical planes,numerical experiments and CPU time-methodology.Dynamical planes of iterative methods are drawn by using MATLAB for the comparison of global convergence properties of simultaneous iterative methods.Convergence behavior of the higher order simultaneous iterative methods are also illustrated by residual graph obtained from some numerical test examples.Numerical test examples,dynamical behavior and computational efficiency are provided to present the performance and dominant efficiency of the newly constructed derivative free family of simultaneous iterative method over existing higher order simultaneous methods in literature. 展开更多
关键词 Non-linear equation iterative method simultaneous method basins of attractions computational efficiency
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Experimental Consideration of Two-Dimensional Fourier Transform Spectroscopy 被引量:1
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作者 Liang Zhou Lie Tian Wen-kai Zhang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2020年第4期385-393,I0001,共10页
Two-dimensional Fourier transform(2D FT) spectroscopy is an important technology that developed in recent decades and has many advantages over other ultrafast spectroscopy methods. Although 2D FT spectroscopy provides... Two-dimensional Fourier transform(2D FT) spectroscopy is an important technology that developed in recent decades and has many advantages over other ultrafast spectroscopy methods. Although 2D FT spectroscopy provides great opportunities for studying various complex systems, the experimental implementation and theoretical description of 2D FT spectroscopy measurement still face many challenges, which limits their wide application.Recently, the 2D FT spectroscopy reaches maturity due to many new developments which greatly reduces the technical barrier in the experimental implementation of the 2D FT spectrometer. There have been several different approaches developed for the optical design of the 2D FT spectrometer, each with its own advantages and limitations. Thus, a procedure to help an experimentalist to build a 2D FT spectroscopy experimental apparatus is needed.This tutorial review is intending to provide an accessible introduction for a beginner to build a 2D FT spectrometer. 展开更多
关键词 Two-dimensional Fourier transform spectroscopy Two-dimensional infrared spectroscopy Two-dimensional electronic spectroscopy
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Acetic acid-and furfural-based adaptive evolution of Saccharomyces cerevisiae strains for improving stress tolerance and lignocellulosic ethanol production 被引量:1
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作者 Omama Rehman Youduo Wu +7 位作者 Quan Zhang Jin Guo Cuihuan Sun Huipeng Gao Yaqing Xu Rui Xu Ayesha Shahid Chuang Xue 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第8期26-33,共8页
Acetic acid and furfural are known as prevalent inhibitors deriving from pretreatment during lignocellulosic ethanol production.They negatively impact cell growth,glucose uptake and ethanol biosynthesis of Saccharomyc... Acetic acid and furfural are known as prevalent inhibitors deriving from pretreatment during lignocellulosic ethanol production.They negatively impact cell growth,glucose uptake and ethanol biosynthesis of Saccharomyces cerevisiae strains.Development of industrial S.cerevisiae strains with high tolerance towards these inhibitors is thus critical for efficient lignocellulosic ethanol production.In this study,the acetic acid or furfural tolerance of different S.cerevisiae strains could be significantly enhanced after adaptive evolution via serial cultivation for 40 generations under stress conditions.The acetic acid-based adaptive strain SPSC01-TA9 produced 30.5 g·L^(-1)ethanol with a yield of 0.46 g·g^(-1)in the presence of 9 g·L^(-1)acetic acid,while the acetic acid/furfural-based adaptive strain SPSC01-TAF94 produced more ethanol of 36.2 g·L^(-1)with increased yield up to 0.49 g·g^(-1)in the presence of both 9 g·L^(-1)acetic acid and 4 g·L^(-1)furfural.Significant improvements were also observed during non-detoxified corn stover hydrolysate culture by SPSC01-TAF94,which achieved ethanol production and yield of 29.1 g·L^(-1)and 0.49 g·g^(-1),respectively,the growth and fermentation efficiency of acetic acid/furfural-based adaptive strain in hydrolysate was 95%higher than those of wildtype strains,indicating the acetic acid-and furfural-based adaptive evolution strategy could be an effective approach for improving lignocellulosic ethanol production.The adapted strains developed in this study with enhanced tolerance against acetic acid and furfural could be potentially contribute to economically feasible and sustainable lignocellulosic biorefinery. 展开更多
关键词 Saccharomyces cerevisiae Lignocellulosic ethanol production Adaptive evolution Acetic acid FURFURAL
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Long-term photometric study of a faint W UMa binary in the direction of M31 被引量:1
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作者 Yogesh Chandra Joshi Rukmini Jagirdar 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2017年第11期59-70,共12页
We carry out a re-analysis of the photometric data in Rclc bands which were taken during the Nainital Microlensing Survey from 1998 to 2002 with the aim to detect gravitational microlensing events in the direction of ... We carry out a re-analysis of the photometric data in Rclc bands which were taken during the Nainital Microlensing Survey from 1998 to 2002 with the aim to detect gravitational microlensing events in the direction of M31. Here, we do photometric analysis of a faint W UMa binary CSS_JO04259.3+410629 identified in the target field. The orbital period of this star is found to be 0.266402±0.000018 d. The photometric mass ratio, q, is found to be 0.28±0.01. The photometric light curves are investigated using the Wilson-Devinney (WD) code and absolute parameters are determined using empirical relations which provide masses and radii of the binary as M1 = 1.19±0.09M⊙, M2 = 0.33±0.02M⊙ and R1 = 1.02±0.04R⊙, R2 = 0.58±0.08Re respectively based on Rc band data. Quite similar values are found by analyzing/c band data. From the photometric light curve examination, the star is understood to be a low mass-ratio overcontact binary of A-subtype with a high fill-out factor of about 47%. The binary system is found to be located approximately at a distance of 2.64±0.03 kpc having a separation of 2.01 ±0.05 Re between the two components. 展开更多
关键词 methods: observational -- techniques: photometric -- binaries: eclipsing -- stars: funda- mental parameters
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