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Weak Co-AB-context for G_(C)-χ-injective Modules
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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
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An RMD-YOLOv11 Approach for Typical Defect Detection of PV Modules
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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
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Remaining Life Prediction Method for Photovoltaic Modules Based on Two-Stage Wiener Process 被引量:1
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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
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A review of encapsulation methods and geometric improvements of perovskite solar cells and modules for mass production and commercialization 被引量:1
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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
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A Two-Stage Wiener Degradation Model-Based Approach for Visual Maintenance of Photovoltaic Modules 被引量:1
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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
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Hydrophobic surface release and energy-level alignment of PTAA enables stable flexible perovskite solar modules
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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
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Simple Yetter-Drinfeld Modules over a Non-Pointed Hopf Algebra
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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
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Wood-derived catalysts for green and stable Fenton-like chemistry:From basic mechanisms to catalytic modules and future inspiration
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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
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Modified Near‑Infrared Annealing Enabled Rapid and Homogeneous Crystallization of Perovskite Films for Efficient Solar Modules
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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
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Instructional Modules for Constructivist Environmental Learning in Science,Technology and Society(STS)Subject
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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
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Additive engineering for colloid stabilization and crystallization control in slot-die coated large-area solar modules
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作者 Xinxin Li Long Zhou +9 位作者 Dazheng Chen Weidong Zhu He Xi Hang Dong Wenming Chai Hui Wang Chunxiang Zhu Jincheng Zhang Yue Hao Chunfu Zhang 《Journal of Energy Chemistry》 2025年第12期935-943,I0020,共10页
Scalable fabrication of homogeneous perovskite films remains crucial for bridging the efficiency gap between lab-scale solar cells and commercial solar modules.To tackle this issue,we introduce NCyano-4-methyl-N-pheny... Scalable fabrication of homogeneous perovskite films remains crucial for bridging the efficiency gap between lab-scale solar cells and commercial solar modules.To tackle this issue,we introduce NCyano-4-methyl-N-phenylbenzenesulfonamide(CMPS) additives into perovskite precursors,enabling slot-die coating of large-area modules under ambient conditions.CMPS suppresses colloidal aggregation and delays crystallization,yielding high-quality uniform films.Small-area devices(0.07 cm^(2) aperture area) incorporating CMPS exhibited a significant efficiency increase from 22.07 % to 24.58 %.Corresponding encapsulated devices maintained 85 % of their initial power conversion efficiency(PCE,average 23.56 %) after 1500 h of continuous maximum power point(MPP) tracking under one-sun illumination at 50-55℃.Furthermore,we demonstrate impressive efficiency of perovskite solar modules,achieving 20.57 %(52 cm^(2) aperture area) for 10 cm × 10 cm mini-modules and 17.02 %(260 cm^(2) aperture area) for 21 cm × 21 cm sub-modules,representing the state-of-the-art performance for solutionprocessed devices at these scales. 展开更多
关键词 Slot-die coating Buried interface defects Multi-point synergistic passivation Perovskite solar modules
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Performance and Degradation Assessment of PV Modules Exposed to Short-Term Outdoor Conditions in Two Distinct US Climatic Zones
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作者 Bouasria Youssef Zaimi Mhammed +1 位作者 ElAinaoui Khadija Assaid El Mahdi 《Energy Engineering》 2025年第10期4195-4223,共29页
Current research focuses on the performance degradation of photovoltaic(PV)modules,examining both crystalline silicon(p-Si and m-Si)and thin-film technologies,including a-Si/μc-Si,HIT,CdTe and CIGS.These modules were... Current research focuses on the performance degradation of photovoltaic(PV)modules,examining both crystalline silicon(p-Si and m-Si)and thin-film technologies,including a-Si/μc-Si,HIT,CdTe and CIGS.These modules were operated outdoors in two distinct climatic zones in the United States(US)over a period of three years.The degradation analysis includes the study of various quantities,such as the decrease in peak power,the reduction in current and voltage,and the variation in the fill factor.The annual degradation rate(DR)of PV modules is obtained by a linear fit of the effective maximum power evolution over time.The results indicate that m-Si and p-Si modules experienced a slight decrease in performance,with DRs of−0.83%and−1.07%,respectively.Subsequently,the HIT module exhibited a DR of−1.75%,while CdTe and CIGS modules demonstrated DRs of−2.03%and−2.45%,respectively.The a-Si/μc-Si module showed the highest DR at−3.26%.Using the Single Diode Model(SDM),we monitored the temporal evolution of physical parameters as well as changes in the shape of the I-V and P-V curves over time.We found that the key points of the I-V curve degrade over time,as do the I-V and P-V characteristics between two days approximately 30 months apart. 展开更多
关键词 PV module crystalline silicon thin-film technologies outdoor test effective maximum power degradation rate single diode model
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Synergistic p-doping and interface passivation of P3HT by oxidized organic small molecules toward efficient and stable perovskite solar modules
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作者 Pin Lv Yuxi Zhang +9 位作者 Wen Liang Tan Junye Pan Yanqing Zhu Jiahui Chen Bingxin Duan Peiran Hou Min Hu Christopher R.Mc Neill Jianfeng Lu Yi-Bing Cheng 《Journal of Energy Chemistry》 2025年第9期477-484,I0013,共9页
Poly(3-hexylthiophene)(P3HT)is one of the most promising hole-transporting materials in the pursuit of efficient and stable perovskite solar cells due to its outstanding stability and low cost.However,the intrinsic lo... Poly(3-hexylthiophene)(P3HT)is one of the most promising hole-transporting materials in the pursuit of efficient and stable perovskite solar cells due to its outstanding stability and low cost.However,the intrinsic low carrier density of P3 HT and poor contact between the P3HT/perovskite interface always lead to a low performance of the solar cell,while conventional chemical doping always makes the films unstable and limits the scalability.In this work,for the first time,we simultaneously enhanced the hole transporting properties of P3HT film and the interface of perovskite by doping it with a judiciously designed oxidized small molecule organic semiconductor.The organic salt not only can promote the lamellar crystallinity of P3HT to obtain better charge transport properties,but also reduce the defects of perovskite.As a result,we achieved champion efficiencies of 23.0%for small-area solar cells and 18.8%for larger-area modules(48.0 cm^(2)).This efficiency is the highest value for P3HT-based perovskite modules.Moreover,the solar cells show excellent operational stability,retaining over 95%of their initial efficiencies after1200 h of continuous operation. 展开更多
关键词 P3HT doping Perovskite solar cells Perovskite solar modules Small molecule organic semiconductor Interface passivation
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吗啉离子液体型催化剂催化合成碳酸甲乙酯
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作者 张卫红 朱颖 +1 位作者 邹凯 刘平 《石油化工》 北大核心 2026年第3期334-340,共7页
以十六烷基三甲基溴化铵、N-(3-(三甲氧基硅基丙基))-N-甲基吗啉氯盐([MMpSi]Cl)和正硅酸四乙酯为原料制备了吗啉离子液体型催化剂MCM-41-x[MMpSi]OH,采用FTIR、TG、N2吸附-脱附、小角XRD、CO_(2)-TPD等方法对MCM-41-x[MMpSi]OH进行表征... 以十六烷基三甲基溴化铵、N-(3-(三甲氧基硅基丙基))-N-甲基吗啉氯盐([MMpSi]Cl)和正硅酸四乙酯为原料制备了吗啉离子液体型催化剂MCM-41-x[MMpSi]OH,采用FTIR、TG、N2吸附-脱附、小角XRD、CO_(2)-TPD等方法对MCM-41-x[MMpSi]OH进行表征,并将其用于乙醇与碳酸二甲酯(DMC)酯交换生成碳酸甲乙酯(EMC)的反应,通过优化反应条件研究了MCM-41-x[MMpSi]OH的催化性能。实验结果表明,MCM-41-x[MMpSi]OH催化剂的碱量随[MMpSi]Cl负载量的增大而增大,[MMpSi]Cl负载量(摩尔分数)为0.075的MCM-41-0.075[MMpSi]OH催化剂碱量适中、催化性能最好,在乙醇与DMC的摩尔比为4∶1、80℃、5 h、催化剂用量1.5%(w)的优化反应条件下,采用该催化剂时EMC收率为65.0%(w)、EMC选择性为93.2%,循环使用10次后催化性能仍保持稳定。 展开更多
关键词 吗啉离子液体 MCM-41 碳酸甲乙酯 酯交换反应
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双频调制转移光谱激光自动稳频方法
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作者 谢建东 郭向阳 +2 位作者 严利平 楼盈天 陈本永 《仪器仪表学报》 北大核心 2026年第1期181-190,共10页
为克服传统单频调制转移光谱方法中误差信号灵敏度不足及激光锁定状态判断困难的问题,提出了一种双频调制转移光谱的双频调制转移光谱(DF-MTS)激光频率自动稳频方法。该方法在泵浦光上施加双频正弦相位调制,解调获得两个误差信号并叠加... 为克服传统单频调制转移光谱方法中误差信号灵敏度不足及激光锁定状态判断困难的问题,提出了一种双频调制转移光谱的双频调制转移光谱(DF-MTS)激光频率自动稳频方法。该方法在泵浦光上施加双频正弦相位调制,解调获得两个误差信号并叠加,构建出一个高灵敏度的双频调制转移误差信号。同时,引入了基于二倍频信号辅助的激光锁定判别策略,利用吸收信号中的二倍频信号以及误差信号的幅值信息,判断激光频率是否与吸收峰对准,实现吸收峰的自动识别与锁定状态的快速判别。进一步在可编程逻辑门阵列(FPGA)全硬件实时信号处理技术的基础上设计了全自动稳频控制模块,具备双频误差信号解调、二倍频信号解调、识别-控制-监测控制模块(ICM)识别与控制监测、扫描控制、比例-积分-微分(PID)闭环控制、快速重锁等功能,当检测到失锁时会快速重新锁定,可实现全自动的稳频控制。开展了理论推导与仿真分析,搭建了激光稳频实验系统,实验结果表明,DF-MTS方法所得的误差信号灵敏度较传统方法提升了20.24%。进一步利用飞秒光频梳进行拍频测量,验证了激光成功锁定于&(85) Rb D2线(F=2→F′=3)吸收峰,锁定后稳频激光与吸收峰理论值间频差的标准差为17 kHz,相对阿伦偏差可达1.09×10^(-11)。自动重锁实验结果表明,系统可实时监测激光的锁定状态,检测到失锁后可在40.192 ms内完成重新锁定,展现出良好的动态响应能力与鲁棒性。 展开更多
关键词 激光稳频 调制转移光谱技术 双频调制 二倍频 自动重锁
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不同管电压联合器官剂量调制技术对脑灌注图像质量及眼晶体辐射剂量的影响研究 被引量:1
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作者 马文涛 张永县 +2 位作者 郭森林 刘云福 康天良 《CT理论与应用研究(中英文)》 2026年第1期102-111,共10页
目的:探讨不同管电压下启用器官剂量调制(ODM)技术在颅脑CT灌注(CTP)中对图像质量及眼晶体辐射剂量的影响。方法:以临床CTP扫描方案为基准,在其他参数相同情况下分别使用5种管电压(70、80、100、120和140 kV)对Catphan模体和一具离体头... 目的:探讨不同管电压下启用器官剂量调制(ODM)技术在颅脑CT灌注(CTP)中对图像质量及眼晶体辐射剂量的影响。方法:以临床CTP扫描方案为基准,在其他参数相同情况下分别使用5种管电压(70、80、100、120和140 kV)对Catphan模体和一具离体头颅标本进行3种管电流调制模式的扫描:不使用剂量调制技术(Manual模式)、使用智能管电流调制技术(Smart mA模式)、使用器官剂量调制技术(ODM模式)。在右眼晶体前方相同位置固定长杆电离室,每组参数重复9次扫描,记录平均眼晶体剂量值(Dav)。对Catphan模体中CTP528高对比分辨力模块进行调制传递函数(MTF)的测量。在头颅标本影像中的基底节层面选取尾状核头、豆状核、丘脑作为信号区,选取侧脑室、内囊前肢、内囊后肢作为对应背景区,测算对比度噪声比(CNR)。分割同层面脑组织测量纹理对比度、纹理相关性、差分方差等3项纹理特征参数。对MTF、CNR的比较采用两因素方差分析,对晶体剂量、图像纹理的比较采用多因素非参数方差分析。结果:MTF在不同管电压间差异具有统计学意义,在80 kV以上时其值与管电压呈正相关,在不同管电流调制模式间差异无统计学意义。各信号区与背景区间的CNR在不同管电压间差异均有统计学意义,其中尾状核头−侧脑室的CNR值在120 kV时最大。后两者的CNR值与管电压呈负相关;三者的CNR值在不同管电流调制模式间差异均无统计学意义。各纹理参数与管电流调制模式无关。不同管电压和管电流调制模式下的Dav值差异均存在统计学意义,在管电压120 kV以下时晶体剂量与管电压呈负相关,各管电压下ODM技术均可降低约20%的晶体剂量。结论:使用80~100 kV进行CTP扫描并启用器官剂量调制(ODM)技术可均衡图像的各参数指标,在保证图像质量前提下降低眼晶体辐射剂量,建议临床推广使用。 展开更多
关键词 颅脑灌注CT 器官剂量调制 眼晶状体 图像质量
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基于改进哈里斯鹰算法的光伏清扫机械臂优化
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作者 唐术锋 于慧 +2 位作者 王鑫 郭晓栋 常宏 《太阳能学报》 北大核心 2026年第2期140-147,共8页
针对现有光伏组件清扫机械臂在常用工作空间性能不高的问题,提出一种改进哈里斯鹰优化算法对机械臂的结构尺寸进行优化,该算法结合正交交叉算子,使得局部搜索能力变得更强。根据实际发电厂光伏组件安装参数,建立常用工作空间的约束指标... 针对现有光伏组件清扫机械臂在常用工作空间性能不高的问题,提出一种改进哈里斯鹰优化算法对机械臂的结构尺寸进行优化,该算法结合正交交叉算子,使得局部搜索能力变得更强。根据实际发电厂光伏组件安装参数,建立常用工作空间的约束指标,并将常用工作空间的全局性能和结构长度两个指标作为目标函数。仿真试验结果表明,改进后的算法寻优更快,针对提出的两个指标分别提高21.27%和8.72%,相同作业环境下,优化后的机械臂到达目标位置所需时间相对于优化前缩短21.7%,机械臂的灵活性提高,清扫光伏组件的效率提升。 展开更多
关键词 光伏组件 机器人 机械臂 光伏组件清扫机器人 哈里斯鹰优化算法 结构优化 移动机器人
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基于气隙磁场调制理论的永磁同步电机偏心故障分析
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作者 丁石川 金岱晨 +3 位作者 杭俊 程明 李亚 孙乐 《中国电机工程学报》 北大核心 2026年第4期1640-1650,I0029,共12页
该文基于气隙磁场调制理论实现了对永磁同步电机发生偏心故障时的电磁性能统一性分析,丰富和发展了气隙磁场调制理论。将偏心故障对气隙的改变抽象成“调制器”,并定义“偏心调制算子”,以体现偏心故障对电机气隙的影响,进而研究偏心故... 该文基于气隙磁场调制理论实现了对永磁同步电机发生偏心故障时的电磁性能统一性分析,丰富和发展了气隙磁场调制理论。将偏心故障对气隙的改变抽象成“调制器”,并定义“偏心调制算子”,以体现偏心故障对电机气隙的影响,进而研究偏心故障对气隙磁场的调制作用,分析偏心故障对永磁同步电机空载反电势、电磁转矩、径向电磁力波、不平衡磁拉力及电感的影响。有限元仿真与实验结果表明,偏心故障产生的谐波对空载反电势几乎无有影响,但会产生转矩脉动,对电机的径向电磁力波和不平衡磁拉力会有严重影响,同时,气隙的变化也会造成电感变化。 展开更多
关键词 永磁同步电机 气隙磁场调制理论 偏心故障 偏心调制算子 电磁性能
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基于振动声调制法的钢-混凝土界面损伤识别
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作者 霍林生 张涛 +1 位作者 赵楠 杨卓栋 《振动.测试与诊断》 北大核心 2026年第1期163-171,223,共10页
针对传统的线性超声理论在钢-混凝土界面损伤检测中存在准确性低的问题,提出一种基于非线性超声调制理论的钢-混凝土界面损伤识别方法。首先,在钢管混凝土内部嵌入智能骨料以激发高频超声信号,同时利用外部电磁激振器施加低频振动,从而... 针对传统的线性超声理论在钢-混凝土界面损伤检测中存在准确性低的问题,提出一种基于非线性超声调制理论的钢-混凝土界面损伤识别方法。首先,在钢管混凝土内部嵌入智能骨料以激发高频超声信号,同时利用外部电磁激振器施加低频振动,从而调制出在频域上具有非线性特征的超声信号;其次,在钢管外壁的3个不同位置粘贴传感器,用于接收并记录经过界面调制的响应信号;然后,利用万能试验机开展加载试验,诱导钢-混凝土界面产生不同程度的黏结失效,并定量分析界面裂缝扩展与损伤指标之间的变化规律;最后,通过对比分析验证该方法的有效性。结果表明:所提出的损伤指标随着裂缝的扩展呈现单调递增趋势,能够比传统的线性超声方法更准确地反映界面的损伤状况,为钢-混凝土组合结构的界面损伤检测提供了新的思路。 展开更多
关键词 非线性超声 振动声调制 调制边频 钢-混凝土界面 压电陶瓷
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计及储能调频能力的高比例新能源电力系统优化调度 被引量:1
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作者 林俐 丁文敏 +2 位作者 唐传伟 马笑寒 赵冬梅 《华北电力大学学报(自然科学版)》 北大核心 2026年第1期1-11,I0001,I0002,共13页
随着可再生能源大量并网,其波动性、间歇性给电网调峰调频带来了困难和挑战,而储能作为优质的调节资源可以缓解日益增长的调峰与频率响应压力。据此,本文分析多源联合系统的惯性响应和一次调频机理,研究电化学储能的频率响应能力,确定... 随着可再生能源大量并网,其波动性、间歇性给电网调峰调频带来了困难和挑战,而储能作为优质的调节资源可以缓解日益增长的调峰与频率响应压力。据此,本文分析多源联合系统的惯性响应和一次调频机理,研究电化学储能的频率响应能力,确定其非调峰阶段的基本调频容量;以最大化利用储能为目标,对电化学储能荷电状态进行分区,提出一种基于SoC的储能调频容量增量划分方法。以净负荷波动最小为目标确定储能调频的时间区间、容量;以系统运行成本最低最大消纳新能源为目标构建计及储能调频能力的高比例新能源电力系统双层优化调度模型;最后,选取改进IEEE-39节点算例系统进行分析,验证所提模型的有效性和可行性。 展开更多
关键词 储能 优化调度 调峰调频 新能源消纳 多源联合
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