期刊文献+
共找到149,421篇文章
< 1 2 250 >
每页显示 20 50 100
Weak Co-AB-context for G_(C)-χ-injective Modules
1
作者 YANG Qiang 《数学进展》 北大核心 2026年第1期103-119,共17页
In this paper,we introduce the notion of G_(C)-X-injective modules,where X denotes a class of left S-modules and C represents a faithfully semidualizing bimodule.Under the condition that X satisfies certain hypotheses... In this paper,we introduce the notion of G_(C)-X-injective modules,where X denotes a class of left S-modules and C represents a faithfully semidualizing bimodule.Under the condition that X satisfies certain hypotheses,some properties and some equivalent characterizations of G_(C)-X-injective modules are investigated,and we also show that the triple(■,cores■,■)is a weak co-AB-context.As an application,two complete cotorsion pairs and a new model structure in Mod S are given. 展开更多
关键词 C-X-injective module G_(C)-X-injective module cotorsion pair weak co-ABcontext
原文传递
Stableδ-FA(Cs)PbI_(3)intermediate enables fabrication of large-area perovskite solar modules in ambient air
2
作者 Chenyang Duan Ke Xiao +12 位作者 Yinke Wang Ye Liu Yameen Ahmed Zhentao Pang Wenjun Zhan Hongfei Sun Han Gao Haowen Luo Yuhong Zhang Xin Luo Yu Deng Makhsud I.Saidaminov Hairen Tan 《Science China Materials》 2026年第3期1456-1463,共8页
Fabrication of large-area perovskite solar modules under ambient air conditions remains a critical challenge due to air sensitivity of perovskite intermediate phases during crystallization.Here,we introduce 2-iodoimid... Fabrication of large-area perovskite solar modules under ambient air conditions remains a critical challenge due to air sensitivity of perovskite intermediate phases during crystallization.Here,we introduce 2-iodoimidazole(IIZ)into the perovskite precursor,enabling the formation of an air-stable pureδ-phase intermediate,which,upon annealing,fully transforms into a highly orientedα-phase perovskite film with reduced defects and variability.Leveraging this approach,we achieve a stabilized power conversion efficiency of 20.9%for 927.5 cm^(2)perovskite solar modules with high reproducibility.The encapsulated modules meet stringent international photovoltaic testing standards(IEC61215:2021),demonstrating excellent stability under continuous operation,thermal cycling(-40 to 85℃)and damp heat(85℃ and 85%relative humidity). 展开更多
关键词 perovskite solar modules intermediate phases ambient fabrication scalable fabrication stability
原文传递
An RMD-YOLOv11 Approach for Typical Defect Detection of PV Modules
3
作者 Tao Geng Shuaibing Li +3 位作者 Yunyun Yun Yongqiang Kang Hongwei Li unmin Zhu 《Computers, Materials & Continua》 2026年第3期1804-1822,共19页
In order to address the challenges posed by complex background interference,high miss-detection rates of micro-scale defects,and limited model deployment efficiency in photovoltaic(PV)module defect detection,this pape... In order to address the challenges posed by complex background interference,high miss-detection rates of micro-scale defects,and limited model deployment efficiency in photovoltaic(PV)module defect detection,this paper proposes an efficient detection framework based on an improved YOLOv11 architecture.First,a Re-parameterized Convolution(RepConv)module is integrated into the backbone to enhance the model’s sensitivity to fine-grained defects—such as micro-cracks and hot spots—while maintaining high inference efficiency.Second,a Multi-Scale Feature Fusion Convolutional Block Attention Mechanism(MSFF-CBAM)is designed to guide the network toward critical defect regions by jointly modeling channel-wise and spatial attention.This mechanism effectively strengthens the specificity and robustness of feature representations.Third,a lightweight Dynamic Sampling Module(DySample)is employed to replace conventional upsampling operations,thereby improving the localization accuracy of small-scale defect targets.Experimental evaluations conducted on the PVEL-AD dataset demonstrate that the proposed RMDYOLOv11 model surpasses the baseline YOLOv11 in terms of mean Average Precision(mAP)@0.5,Precision,and Recall,achieving respective improvements of 4.70%,1.51%,and 5.50%.The model also exhibits notable advantages in inference speed and model compactness.Further validation on the ELPV dataset confirms the model’s generalization capability,showing respective performance gains of 1.99%,2.28%,and 1.45%across the same metrics.Overall,the enhanced model significantly improves the accuracy of micro-defect identification on PV module surfaces,effectively reducing both false negatives and false positives.This advancement provides a robust and reliable technical foundation for automated PV module defect detection. 展开更多
关键词 Photovoltaic(PV)modules YOLOv11 re-parameterization convolution attention mechanism dynamic upsampling
在线阅读 下载PDF
Remaining Life Prediction Method for Photovoltaic Modules Based on Two-Stage Wiener Process 被引量:1
4
作者 Jie Lin Hongchi Shen +1 位作者 Tingting Pei Yan Wu 《Energy Engineering》 EI 2025年第1期331-347,共17页
Photovoltaic (PV) modules, as essential components of solar power generation systems, significantly influence unitpower generation costs.The service life of these modules directly affects these costs. Over time, the p... Photovoltaic (PV) modules, as essential components of solar power generation systems, significantly influence unitpower generation costs.The service life of these modules directly affects these costs. Over time, the performanceof PV modules gradually declines due to internal degradation and external environmental factors.This cumulativedegradation impacts the overall reliability of photovoltaic power generation. This study addresses the complexdegradation process of PV modules by developing a two-stage Wiener process model. This approach accountsfor the distinct phases of degradation resulting from module aging and environmental influences. A powerdegradation model based on the two-stage Wiener process is constructed to describe individual differences inmodule degradation processes. To estimate the model parameters, a combination of the Expectation-Maximization(EM) algorithm and the Bayesian method is employed. Furthermore, the Schwarz Information Criterion (SIC) isutilized to identify critical change points in PV module degradation trajectories. To validate the universality andeffectiveness of the proposed method, a comparative analysis is conducted against other established life predictiontechniques for PV modules. 展开更多
关键词 Photovoltaic modules DEGRADATION stochastic processes lifetime prediction
在线阅读 下载PDF
A review of encapsulation methods and geometric improvements of perovskite solar cells and modules for mass production and commercialization 被引量:1
5
作者 Wending Yang Yubo Zhang +2 位作者 Chengchao Xiao Jingxuan Yang Tailong Shi 《Nano Materials Science》 2025年第6期790-809,共20页
Owing to the outstanding optoelectronic properties of perovskite materials,perovskite solar cells(PSCs)have been widely studied by academic organizations and industry corporations,with great potential to become the ne... Owing to the outstanding optoelectronic properties of perovskite materials,perovskite solar cells(PSCs)have been widely studied by academic organizations and industry corporations,with great potential to become the next-generation commercial solar cells.However,critical challenges remain in preserving high efficiency practical large-scale commercialized PSCs:a)the long-term stability of the cell materials and devices,b)lead leakage,and c)methods to scale the cells for larger area applications.This paper summarizes the prior-art strategies to address the above challenges,including the latest studies on the traditional glass-glass and thin-film encapsulation methods to better improve the reliability of PSCs,new technologies for preventing lead leakage,and geometric improvement strategies to enhance the reliability,efficiency,and performance of perovskite solar modules(PSMs).Through these strategies,the device achieved enhanced performance in long-term stability tests.The encapsulation resulted in a high lead leakage inhibition rate of up to 99%,and the PSMs possessed a geometric fill factor of 99.6%and a power conversion efficiency(PCE)of 20.7%.The dramatic improvement of efficiency and reliability of perovskite solar cells and modules indicate the great potential for mass production and commer-cialization of perovskite solar applications in the near future. 展开更多
关键词 Perovskite solar modules ENCAPSULATION Geometric improvement Stability COMMERCIALIZATION
在线阅读 下载PDF
Highly flexible and excellent performance continuous carbon nanotube fibrous thermoelectric modules for diversified applications 被引量:1
6
作者 Xiao-Gang Xia Qiang Zhang +4 位作者 Wen-Bin Zhou Zhuo-Jian Xiao Wei Xi Yan-Chun Wang Wei-Ya Zhou 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第7期100-106,共7页
A highly flexible and continuous fibrous thermoelectric(TE)module with high-performance has been fabricated based on an ultra-long single-walled carbon nanotube fiber,which effectively avoids the drawbacks of traditio... A highly flexible and continuous fibrous thermoelectric(TE)module with high-performance has been fabricated based on an ultra-long single-walled carbon nanotube fiber,which effectively avoids the drawbacks of traditional inorganic TE based modules.The maximum output power density of a 1-cm long fibrous TE module with 8 p–n pairs can reach to 3436μW·cm^(-2),the power per unit weight to 2034μW·g^(-1),at a steady-state temperature difference of 50 K.The continuous fibrous TE module is used to detect temperature change of a single point,which exhibits a good responsiveness and excellent stability.Because of its adjustability in length,the flexible fibrous TE module can satisfy the transformation of the temperature difference between two distant heat sources into electrical energy.Based on the signal of the as-fabricated TE module,a multi-region recognizer has been designed and demonstrated.The highly flexible and continuous fibrous TE module with excellent performance shows a great potential in diversified applications of TE generation,temperature detection,and position identification. 展开更多
关键词 carbon nanotube fiber power density fibrous thermoelectric module
原文传递
Bending Characteristics of Folded Multi-celled Tubes with Square and Circular Section Geometries
7
作者 Rui Liang Fengxiang Xu +3 位作者 Zhen Zou Xiaoqiang Niu Xuebang Tang Tingpeng Li 《Acta Mechanica Solida Sinica》 2025年第1期125-141,共17页
This research investigates the bending response of folded multi-celled tubes(FMTs)fabricated by folded metal sheets.A three-point bending test for FMTs with circular and square sections is designed and introduced.The ... This research investigates the bending response of folded multi-celled tubes(FMTs)fabricated by folded metal sheets.A three-point bending test for FMTs with circular and square sections is designed and introduced.The base numerical models are correlated with physical experiments and a static crashworthiness analysis of six FMT configurations to assess their energy absorption characteristics.The influences of thickness,sectional shape,and load direction on the bending response are studied.Results indicate that increasing the thickness of the tube and radian of the inner tube enhances the crashworthiness performance of FMT,yielding a 20.50%increase in mean crushing force,a 55.53%increase in specific energy absorption,and an 18.05%decrease in peak crushing force compared to traditional multi-celled tubes(TMTs).A theoretical analysis of the specific energy absorption indicates that FMTs outperform TMTs,particularly when the peak crushing force is prominent.This study highlights the innovative and practical potential of FMTs to improve the crashworthiness of thin-walled structures. 展开更多
关键词 BENDING Folded Multi-celled tube Energy absorption Numerical
原文传递
Seismic performance of RC square columns strengthened with self-compacting concrete-filled steel tubes
8
作者 Zhang Zhaoqiang Cao Yang +2 位作者 Sa Yanru Mu Huiyu Li Xiaowei 《Earthquake Engineering and Engineering Vibration》 2025年第3期763-779,共17页
The behavior of reinforced concrete(RC)square columns strengthened with self-compacting concrete(SCC)-filled steel tubes under cyclic loading was experimentally investigated.Tests were carried out on eleven reinforced... The behavior of reinforced concrete(RC)square columns strengthened with self-compacting concrete(SCC)-filled steel tubes under cyclic loading was experimentally investigated.Tests were carried out on eleven reinforced columns and one unreinforced column.The parameters studied for the strengthened columns included axial compression ratio,reinforcement rate,defect rate,strength of SCC,and the section form of a reinforced steel tube.The results show that the steel tube SCC reinforcement method can effectively strengthen RC columns,exert the restraint effect of steel tube,and delay the development of internal concrete cracks.The method can also significantly improve the bearing capacity of RC columns.Regarding ductility,the improvement of the reinforced column is obvious,the deformation resistance of the specimen is enhanced,and the degradation of stiffness and strength is relatively slow,indicating that it has good seismic performance. 展开更多
关键词 steel tube strengthening self-compacting concrete RC column seismic performance
在线阅读 下载PDF
Hydrophobic surface release and energy-level alignment of PTAA enables stable flexible perovskite solar modules
9
作者 Hua Zhong Jianxing Xia +2 位作者 Hao Tian Chuanxiao Xiao Fei Zhang 《Journal of Energy Chemistry》 2025年第10期448-454,共7页
The fabrication of efficient and stable flexible perovskite solar modules(F-PSMs)using poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine](PTAA)remains a significant challenge due to its hydrophobic properties and the mis... The fabrication of efficient and stable flexible perovskite solar modules(F-PSMs)using poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine](PTAA)remains a significant challenge due to its hydrophobic properties and the mismatch in interface energy-level alignment.Here,we introduced[2-(3,6-dimethoxy-9H-carba zol-9-yl)ethyl]phosphonic acid(MeO-2PACz)to modify the PTAA layer,which effectively suppressed surface potential fluctuations and aligned energy levels at the interface of PTAA/perovskite.Additionally,MeO-2PACz enhanced the hydrophilicity of PTAA,facilitating the fabrication of dense,uniform,and pinhole-free perovskite films on large-area flexible substrates.As a result,we achieved an F-PSM with a power conversion efficiency(PCE)of 16.6% and an aperture area of 64 cm^(2),which is the highest reported value among F-PSMs with an active area exceeding 35 cm^(2)based on PTAA.Moreover,the encapsulated module demonstrated outstanding long-term operational stability,retaining 90.2% of its initial efficiency after 1000 bending cycles(5 mm radius),87.2% after 1000 h of continuous illumination,and 80.3% under combined thermal and humid conditions(85℃ and 85% relative humidity),representing one of the most stable F-PSMs reported to date. 展开更多
关键词 FLEXIBLE Perovskite solar modules STABILITY
在线阅读 下载PDF
Dual-template synthesis of CoNi alloy nanoparticles anchored on N-doped carbon nanotubes for efficient oxygen reduction reaction
10
作者 Shengyi Huang Yao Shen +5 位作者 Ang Li Huiling Zhou Yanxin Qiao Aihua Yuan Hu Zhou Shunli Zheng 《International Journal of Minerals,Metallurgy and Materials》 2025年第12期3043-3051,共9页
The fabrication of one-dimensional metal/N-doped carbon materials has shown a promising prospect as efficient electrocata-lysts for oxygen reduction reaction(ORR).Herein,CoNi alloy nanoparticles anchored on N-doped ca... The fabrication of one-dimensional metal/N-doped carbon materials has shown a promising prospect as efficient electrocata-lysts for oxygen reduction reaction(ORR).Herein,CoNi alloy nanoparticles anchored on N-doped carbon nanotubes(CoNi@NCNT)are prepared by a dual-template strategy,using polypyrrole(PPy)tubes and CoNi-based metal-organic framework as the precursors.The as-formed CoNi@NCNT catalyst displays a half-wave potential(0.83 V)as well as good durability under alkaline medium.The excellent electrocatalytic performance is ascribed to a synergistic coupling of hierarchically tubular structure,highly electronic conductivity,and abundantly alloy-type active sites.When the CoNi@NCNT catalyst is applied in zinc-air battery(ZAB),the device displays a stable charge-discharge cycling performance.The present work affords a useful approach to constructing alloy/nitrogen-incorporated carbon-aceous materials as bifunctional electrocatalysts for high-performance ZABs. 展开更多
关键词 ELECTROCATALYSTS CoNi alloy carbon tubes oxygen evolution reaction zinc-air battery
在线阅读 下载PDF
Development of data acquisition system for induction heating equipment of large caliber coated tubes
11
作者 HE Chunyao WEN Hongquan 《Baosteel Technical Research》 2025年第1期41-46,共6页
In the anticorrosive coating line of a welded tube plant, the current status and existing problems of the medium-frequency induction heating equipment were discussed.Partial renovations of the power control cabinet ha... In the anticorrosive coating line of a welded tube plant, the current status and existing problems of the medium-frequency induction heating equipment were discussed.Partial renovations of the power control cabinet have been conducted.Parameters such as the DC current, DC voltage, intermediate frequency power, heating temperature, and the positioning signal at the pipe end were collected.A data acquisition and processing system, which can process data according to user needs and provide convenient data processing functions, has been developed using LabVIEW software.This system has been successfully applied in the coating line for the automatic control of high-power induction heating equipment, production management, and digital steel tube and/or digital delivery. 展开更多
关键词 induction heating data acquisition data processing coating line welded steel tube
在线阅读 下载PDF
Intelligent reconfiguration of production mechanism for anomalous-performance seamless steel tubes via dual optimization of production cycle and operational loss
12
作者 Ao Guo Ting-song Yang +5 位作者 Jian Shao De-sheng Chen Jing Hao Hui-min Wang Su-yue Wang Can-kun Zhang 《Journal of Iron and Steel Research International》 2025年第12期4359-4376,共18页
Seamless steel tubes,owing to their excellent integrity,structural properties,and processability,are widely applied in industries such as petroleum transportation,power and chemical industries,and national defense.How... Seamless steel tubes,owing to their excellent integrity,structural properties,and processability,are widely applied in industries such as petroleum transportation,power and chemical industries,and national defense.However,the stability of product quality in seamless steel tube production is often poor,particularly regarding the mechanical properties of intermediate products,which may not meet the required standards.This results in non-conforming products being unable to smoothly proceed to downstream processes.These issues mainly arise from the compactness of the production process,the characteristics of batch production,and the difficulty in managing order insertion.Consequently,optimizing the production process to minimize the impact of non-conforming products on subsequent processes has become a key challenge in seamless steel tube production.An intelligent reorganization production mechanism is proposed based on the full life cycle of seamless steel tubes,aiming at addressing the scheduling problems of tubes with abnormal performance.The mechanism utilizes a performance anomaly prediction model to detect and forecast potential anomalies in steel tubes,and in conjunction with intelligent scheduling strategies,rearranges the production plan for abnormal tubes.Experimental results demonstrate that the proposed mechanism can effectively improve the detection rate of abnormal tubes,significantly reduce time losses and energy consumption during production,and optimize both production cycles and stability.Specifically,the production cycle was shortened by 52 h,and energy consumption was reduced by approximately 12%.Through the intelligent scheduling model,the production plan was successfully optimized,reducing the production cycle and costs while improving production efficiency.The optimized scheduling scheme saved about 12%in production time,while enhancing the stability of the production plan and capacity utilization. 展开更多
关键词 Seamless steel tube Mechanical property Multi-objective optimization Production scheduling Order insertion
原文传递
Simple Yetter-Drinfeld Modules over a Non-Pointed Hopf Algebra
13
作者 Ruifang YANG Shilin YANG 《Journal of Mathematical Research with Applications》 2025年第6期716-734,共19页
Let D(n)be the finite dimensional non-pointed and non-semisimple Hopf algebra,which is a quotient of a prime Hopf algebras of GK-dimension one for an odd number n>1.In this paper,we investigate the structure of Yet... Let D(n)be the finite dimensional non-pointed and non-semisimple Hopf algebra,which is a quotient of a prime Hopf algebras of GK-dimension one for an odd number n>1.In this paper,we investigate the structure of Yetter-Drinfeld simple modules over D(n)and give iso-classes of them. 展开更多
关键词 Hopf algebra Yetter-Drinfeld module Nichols algebra
原文传递
Wood-derived catalysts for green and stable Fenton-like chemistry:From basic mechanisms to catalytic modules and future inspiration
14
作者 Xiaoyun Lei Hanghang Zhao +2 位作者 Chao Bai Longlong Geng Xing Xu 《Chinese Chemical Letters》 2025年第10期212-225,共14页
Most carbon-based catalysts utilized in Fenton-like systems face challenges such as structural instability,susceptibility to deactivation,and a tendency to disperse during operation.Wood-derived catalysts have garnere... Most carbon-based catalysts utilized in Fenton-like systems face challenges such as structural instability,susceptibility to deactivation,and a tendency to disperse during operation.Wood-derived catalysts have garnered considerable attention due to their well-defined structures,extensive pipeline networks,superior mechanical strength,and adaptability for device customization.However,there remains a paucity of research that systematically summarizes Fenton-like systems based on wood-derived catalysts.In this review,we first summarize the structural designs of wood-derived catalysts based on nano-metal sites and single-atom sites,while also outlining their advantages and limitations applied in Fenton-like systems.Furthermore,we evaluate catalytic modules of wood-derived catalysts for scale-up and continuous Fenton-like systems.Additionally,wood-inspired catalytic materials utilizing commercial textures and their applications in Fenton-like processes are also discussed.This paper aims to comprehensively explore the fundamental mechanisms(e.g.,characteristics of catalytic sites,catalytic performance,and mechanisms)of wood-based catalysts in Fenton-like chemistry,as well as their equipment designs and application scenarios,as well as providing the insights into future developments. 展开更多
关键词 Wood-derive catalysts Nano-metal Fenton-like chemistry Scale-up application Catalytic modules
原文传递
A Two-Stage Wiener Degradation Model-Based Approach for Visual Maintenance of Photovoltaic Modules
15
作者 Jie Lin Hongchi Shen +1 位作者 Tingting Pei Yan Wu 《Energy Engineering》 2025年第6期2449-2463,共15页
This study proposes a novel visual maintenance method for photovoltaic(PV)modules based on a two-stage Wiener degradation model,addressing the limitations of traditional PV maintenance strategies that often result in ... This study proposes a novel visual maintenance method for photovoltaic(PV)modules based on a two-stage Wiener degradation model,addressing the limitations of traditional PV maintenance strategies that often result in insufficient or excessive maintenance.The approach begins by constructing a two-stage Wiener process performance degradation model and a remaining life prediction model under perfect maintenance conditions using historical degradation data of PV modules.This enables accurate determination of the optimal timing for postfailure corrective maintenance.To optimize the maintenance strategy,the study establishes a comprehensive cost model aimed at minimizing the long-term average cost rate.The model considers multiple cost factors,including inspection costs,preventive maintenance costs,restorative maintenance costs,and penalty costs associated with delayed fault detection.Through this optimization framework,the method determines both the optimal maintenance threshold and the ideal timing for predictive maintenance actions.Comparative analysis demonstrates that the twostage Wiener model provides superior fitting performance compared to conventional linear and nonlinear degradation models.When evaluated against traditional maintenance approaches,including Wiener process-based corrective maintenance strategies and static periodic maintenance strategies,the proposed method demonstrates significant advantages in reducing overall operational costs while extending the effective service life of PV components.The method achieves these improvements through effective coordination between reliability optimization and economic benefit maximization,leading to enhanced power generation performance.These results indicate that the proposed approach offers a more balanced and efficient solution for PV system maintenance. 展开更多
关键词 Photovoltaic module remaining life maintenance strategy Wiener modeling
在线阅读 下载PDF
Shock wave behavior and aerodynamic load in maglev-equipped evacuated tubes:Effects of blockage ratio
16
作者 HUANG Zun-di PENG Cheng +5 位作者 CHEN Zheng-wei GUO Zi-jian CHANG Ning KONG Wei-kai GUO Zhan-hao LU Jia-hao 《Journal of Central South University》 2025年第12期4902-4921,共20页
Evacuated tube transportation(ETT)offers a promising high-speed transport solution,but trains operating at supersonic speeds within a sealed tube can induce complex aerodynamic phenomena that impact safety and reliabi... Evacuated tube transportation(ETT)offers a promising high-speed transport solution,but trains operating at supersonic speeds within a sealed tube can induce complex aerodynamic phenomena that impact safety and reliability.This study utilized the Reynolds-averaged Navier-Stokes(RANS)shear stress transport k-ω(SST k-ω)turbulence model for steady-state simulations and the improved delayed detached eddy simulation(IDDES)SST k-ωmodel for unsteady state simulations,both coupled with the advection upstream splitting method(AUSM).Four tunnel cross-sectional areas(49 m^(2),64 m^(2),81 m^(2),and 100 m^(2))with corresponding blockage ratios(β)(0.253,0.192,0.150,0.121)were analyzed to explore shock wave formation and its dependence on blockage ratios,along with surface pressure distribution and aerodynamic loading.Results show that higher blockage ratios increase shock wave intensity,while larger tunnel areas reduce this intensity,improving flow structure and wake effects.Moreover,as the blockage ratio decreases,the total drag coefficient of the entire train decreases linearly.When the blockage ratio decreases from 0.253 to 0.121,the total drag coefficient of the entire train decreases by 46.2%,with the head carriage and tail carriage drag coefficients decreasing by 23.3%and 32.7%,respectively,while the drag coefficient of the middle carriage remains nearly unchanged.The percentage of the total drag coefficient contributed by the head carriage decreases from 51.1%to 40.9%,while the percentage for the tail carriage increases from 47.0%to 56.6%.These findings enhance understanding of ETT fluid dynamics and performance. 展开更多
关键词 maglev train evacuated tube transportation(ETT) blockage ratio shock wave aerodynamic load
在线阅读 下载PDF
Bending Crashworthiness of Thin⁃Walled Square Tubes Partially Filled with Metallic Foams
17
作者 Zhongyou Xie Limin Guo +1 位作者 Cheng Li Jianwen Cai 《Journal of Harbin Institute of Technology(New Series)》 2025年第2期24-37,共14页
Two cross⁃sectional configurations of thin⁃walled square tubes partially filled with lightweight metallic foams are proposed,and termed as double⁃cell configuration partially filled with foam(DC⁃PF)and double⁃tube con... Two cross⁃sectional configurations of thin⁃walled square tubes partially filled with lightweight metallic foams are proposed,and termed as double⁃cell configuration partially filled with foam(DC⁃PF)and double⁃tube configuration partially filled with foam(DT⁃PF),respectively.The bending crashworthiness is investigated based on three⁃point bending tests using finite element ABAQUS/Explicit code.The two key mechanical indicators including Crash Load Efficiency(CLE)and Specific Energy Absorption(SEA)are introduced to evaluate the effect of foams in comparison with empty square tubes and fully filled square tubes.The numerical results show that the two partially filled configurations,especially DT⁃PF,display dramatically excellent bending crashworthiness compared with empty and fully filled square tubes.There exists a foam density threshold,beyond which the CLE of DT⁃PF achieves a maximum constant.In addition,there seems to be another foam density threshold,beyond which the SEA of DT⁃PF gets to the maximum value.It is also shown that the foam density threshold corresponding to the maximum SEA varies with the thickness of thin⁃walled square tubes. 展开更多
关键词 thin⁃walled tube lightweight foam bending crashworthiness energy absorption finite element analysis
在线阅读 下载PDF
Modified Near‑Infrared Annealing Enabled Rapid and Homogeneous Crystallization of Perovskite Films for Efficient Solar Modules
18
作者 Qing Chang Peng He +10 位作者 Haosong Huang Yingchen Peng Xiao Han Yang Shen Jun Yin Zhengjing Zhao Ye Yang Binghui Wu Zhiguo Zhao Jing Li Nanfeng Zheng 《Nano-Micro Letters》 2025年第11期236-250,共15页
Currently,perovskite solar cells have achieved commendable progresses in power conversion efficiency(PCE)and operational stability.However,some conventional laboratory-scale fabrication methods become challenging when... Currently,perovskite solar cells have achieved commendable progresses in power conversion efficiency(PCE)and operational stability.However,some conventional laboratory-scale fabrication methods become challenging when scaling up material syntheses or device production.Particularly,the prolonged high-temperature annealing process for the crystallization of perovskites requires a substantial amount of energy consumption and impact the modules’throughput.Here,we report a modified near-infrared annealing(NIRA)process,which involves the excess PbI_(2)engineered crystallization,efficiently reduces the preparation time for perovskite active layer to within 20 s compared to dozens of min in conventional hot plate annealing(HPA)process.The study showed that the incorporated PbI_(2)promoted the consistent nucleation of the perovskite film,leading to the subsequent rapid and homogeneous crystallization at the NIRA stage.Thus,highly crystalized perovskite film was realized with even better crystallization performance than conventional HPA-based film.Ultimately,efficient perovskite solar modules of 36 and 100 cm^(2)were readily fabricated with the optimal PCEs of 22.03%and 20.18%,respectively.This study demonstrates,for the first time,the successful achievement of homogeneous and high-quality crystallization in large-area perovskite films through rapid NIRA processing.This approach not only significantly reduces energy consumption during production,but also substantially shortens the manufacturing cycle,paving a new path toward the commercial-scale application of perovskite solar modules. 展开更多
关键词 Near-infrared annealing Homogeneous crystallization Blade coating Perovskite solar modules
在线阅读 下载PDF
Weldability evaluation of in-service ethylene cracking furnace tubes after small punch sampling
19
作者 Jie Wang Yang-yan Zheng Xiang Ling 《Journal of Iron and Steel Research International》 2025年第10期3607-3622,共16页
The small punch test technique facilitates the convenient acquisition of the mechanical properties of in-service equipment materials and the assessment of their remaining service life through sampling.However,the weld... The small punch test technique facilitates the convenient acquisition of the mechanical properties of in-service equipment materials and the assessment of their remaining service life through sampling.However,the weldability of components with thin walls after small punch sampling,such as ethylene cracking furnace tubes,requires further investigation.Therefore,the weldability of in-service ethylene cracking furnace tubes following small punch sampling was investigated through nondestructive testing,microstructural characterization,and mechanical testing.Additionally,the impact of small punch sampling size and residual stress on the creep performance of the specimens was studied using an improved ductility exhaustion model.The results indicate that both the surface and interior of the weld repair areas on new furnace tubes and service-exposed furnace tubes after small-punch sampling are defect-free,exhibiting good weld quality.The strength of the specimens after weld repair was higher than that before sampling,whereas toughness decreased.Weld repair following small punch sampling of furnace tubes is both feasible and necessary.Furthermore,a linear relationship was observed between specimen thickness,diameter,and creep fracture time.The residual stress of welding affects the creep performance of the specimen under different stresses. 展开更多
关键词 Ethylene cracking furnace tube WELDABILITY Small punch sampling MICROSTRUCTURE Mechanical test Ductility exhaustion model
原文传递
Instructional Modules for Constructivist Environmental Learning in Science,Technology and Society(STS)Subject
20
作者 Randy M.Ayong 《Journal of Environmental & Earth Sciences》 2025年第4期126-137,共12页
Modules enable students to engage with content at their own pace,fostering autonomy and deeper understanding.The modular approach ensures clarity in presenting objectives,instructions,and concepts,while having illustr... Modules enable students to engage with content at their own pace,fostering autonomy and deeper understanding.The modular approach ensures clarity in presenting objectives,instructions,and concepts,while having illustrations,activities,and assessments could enhance comprehension and retention.This paper was a developmental study on STS module for college students using the ADDIE Model(Analysis,Design,Development,Implementation,and Evaluation).Sampled 673 first-year students from Northwest Samar State University participated in the study,with 299 participating in a test try-out and 374 in the students’performance evaluation.Three expert evaluators with backgrounds in science,English,and psychology,each with over four years of experience,assessed the modules to ensure alignment with the study’s constructivist learning goals and instructional integrity.The findings revealed that both students and experts had rated the instructional module positively,indicating its effectiveness in facilitating learning and completing lessons.Key aspects such as the style of illustrations and written expressions,the usefulness of learning activities,and the guidance provided by illustrations and captions were especially well-received.The module was praised for its clear objectives,understandable instructions,and engaging tasks like trivia and puzzles.Expert evaluations highlighted relevance,simplicity,and balanced emphasis on topics in the module content.Furthermore,students in test group demonstrated significant improvement in performance,with post-test scores notably higher than pre-test scores,confirming the module’s effectiveness in enhancing learning outcomes.Consequently,this paper provides an opportunity to integrate science learning with initiatives aimed at promoting environmental preservation and driving social change. 展开更多
关键词 Instructional module Environmental Topics Higher Education Curriculum Development Environmental Education
在线阅读 下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部