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Impact of hormone receptor and HER2 conversions on survival after neoadjuvant chemotherapy in breast cancer patients
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作者 Ran Feng Lihui Pan +2 位作者 Yarong Yao Jinnan Gao Xiaojun Zhang 《Oncology and Translational Medicine》 2025年第2期73-80,共8页
Background:This study assessed the frequency of changes in some key receptor status of tumors after neoadjuvant chemotherapy(NAC)in patients with invasive breast cancer and the prognostic impact of these changes.Metho... Background:This study assessed the frequency of changes in some key receptor status of tumors after neoadjuvant chemotherapy(NAC)in patients with invasive breast cancer and the prognostic impact of these changes.Methods:This study included 300 patients diagnosed with invasive breast cancer who were treated with both NAC and surgery between 2012 and 2021.The hormone receptor(HR)and human epidermal growth factor receptor 2(HER2)levels were measured before and after NAC.The prognostic impact of receptor conversion was also evaluated in patients receiving NAC,by using the Kaplan-Meier method and Cox proportional hazards models as statistical methods.Results:The conversion rate of estrogen receptor–positive(ER^(+))to ER-negative(ER^(-))was similar to that of ER^(-)to ER^(+)(9.2%and10.9%,respectively).The proportion of HR^(-)to HR^(+)was remarkably higher than that of HR^(+)to HR^(-)(14.8%vs 9.2%,respectively).The change from HER2^(+)to HER2^(-)was significantly more frequently than that from HER2^(-)to HER2^(+)(20.3%vs 6%,respectively).Patients with ER and HR status changes from(-)to(+)after NAC had significantly worse recurrence-free survival(RFS)and overall survival(OS)than those in the other 3 groups(ER^(-)to ER^(+):RFS:p=0.002,OS:p<0.001;HR^(-)to HR^(+):RFS:p=0.003,OS:p<0.001).The 4 HER2 conversion subgroups were not significantly associated with RFS or OS.Conclusions:This study demonstrated a discordance in HR status after NAC and identified predictors of conversion.Patients whose HR status switched to positive after NAC had the worst 3-year RFS and OS rates. 展开更多
关键词 Neoadjuvant chemotherapy Breast cancer Receptor conversions DISCORDANCE Prognostic impact
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Established conversions for hybrid entangled states assisted by error-predicted parity-discriminated devices
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作者 Fang-Fang Du Zhi-Guo Fan +2 位作者 Xue-Mei Ren Ming Ma Wen-Yao Liu 《Chinese Physics B》 2025年第1期72-78,共7页
Hybrid entangled states are crucial in quantum physics,offering significant benefits for hybrid quantum communication and quantum computation,and then the conversion of hybrid entangled states is equally critical.This... Hybrid entangled states are crucial in quantum physics,offering significant benefits for hybrid quantum communication and quantum computation,and then the conversion of hybrid entangled states is equally critical.This paper presents two novel schemes,that is,one converts the two-qubit hybrid Knill–Laflamme–Milburn(KLM)entangled state into Bell states and the other one transforms the three-qubit hybrid KLM state into Greenberger–Horne–Zeilinger(GHZ)states assisted by error-predicted and parity-discriminated devices.Importantly,the integration of single photon detectors into the parity-discriminated device enhances predictive capabilities,mitigates potential failures,and facilitates seamless interaction between the nitrogen-vacancy center and photons,so the two protocols operate in an error-predicted way,improving the experimental feasibility.Additionally,our schemes demonstrate robust fidelities(close to 1)and efficiencies,indicating their feasibility with existing technology. 展开更多
关键词 quantum information processing quantum entanglement quantum communication entanglement conversion
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高位崩塌碰撞破碎能量转化机制模型试验研究
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作者 黄健 袁圆 +3 位作者 曾探 周琨 袁镜清 李靖恒 《工程科学与技术》 北大核心 2026年第1期167-180,共14页
崩塌落石灾害作为山区常见的主要地质灾害类型,具有显著的突发性与随机性特征,且运动中的碰撞碎裂过程复杂,能量转化机制不明,易造成人员伤亡和财产损失。本文以落石碰撞碎裂现象为切入点,设计了灰岩相似材料法向碰撞试验,通过精细测量... 崩塌落石灾害作为山区常见的主要地质灾害类型,具有显著的突发性与随机性特征,且运动中的碰撞碎裂过程复杂,能量转化机制不明,易造成人员伤亡和财产损失。本文以落石碰撞碎裂现象为切入点,设计了灰岩相似材料法向碰撞试验,通过精细测量试样碰撞碎裂动力学参数,提取相应的能量大小,重点分析不同初始条件下试样碰撞碎裂过程中的能量转化问题。结果表明:碰撞碎裂过程具有明显的阶段性并存在碎裂程度差异。能量耗散主要包括弹塑性变形能与断裂能,占比可达91.94%;剩余碎裂块体的动能仅占比8.05%;能量转化率与初始总能量成负相关。定义基于弹性应变能的碎裂度量化指标,并对比不同材料试样的法向碰撞试验结果,发现落石碰撞碎裂具有一致性规律;进一步对比斜板碰撞试验,发现撞击角度对试样碎裂度影响较大,并且控制了能量的转化效率。上述结论可提升对崩塌落石灾害撞击碎裂过程中能量转化的认识水平,为治理方案设计提供支撑。 展开更多
关键词 崩塌落石 法向碰撞 能量转化 破碎程度
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高能存储密度n-二十烷/SAT/膨胀石墨复合相变材料性能研究
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作者 李亚静 《无机盐工业》 北大核心 2026年第1期60-66,共7页
太阳能作为清洁能源,在应对能源与环境问题方面极具潜力,但因自身不稳定,其利用效率受限。开发高性能相变(PCM)复合材料对太阳能热存储技术意义重大,能有效解决太阳能供需时空不匹配的难题。旨在制备兼具稳定形态、低过冷度和优秀光热... 太阳能作为清洁能源,在应对能源与环境问题方面极具潜力,但因自身不稳定,其利用效率受限。开发高性能相变(PCM)复合材料对太阳能热存储技术意义重大,能有效解决太阳能供需时空不匹配的难题。旨在制备兼具稳定形态、低过冷度和优秀光热转换性能的多孔PCM,以解决太阳能供需时空不匹配问题。研究采用熔融混合工艺,制备以多孔膨胀石墨(EG)为载体材料、n-二十烷为稳定剂、三水合醋酸钠(SAT)为相变储能介质的复合PCMs。研究结果表明,含3.3%(质量分数)膨胀石墨的复合PCM样品性能优异,其相变焓达266.54 J/g,光热转换效率高达91.14%,在90℃时基本无泄漏,过冷度降至2.50℃。此外,EG虽会对相变焓产生负面影响,但由于SAT的高焓值,复合PCMs的焓值仍保持在225.71~268.30 J/g。综上所述,通过EG和n-二十烷改性SAT能有效降低过冷度,提升光热转换效率,为太阳能的高效存储与利用提供可行方案。 展开更多
关键词 相变材料 太阳能储热 膨胀石墨 三水合醋酸钠 光热转换效率
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废弃煤矿巷道CO_(2)“封存-利用”技术探索及转化效率研究
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作者 来兴平 雷彤 +3 位作者 张楠 胡添龙 介凯 刘旭超 《西安科技大学学报》 北大核心 2026年第1期15-26,共12页
为应对全球二氧化碳减排的需求,探索利用废弃煤矿地下空间实现CO_(2)封存与资源化利用的新路径,以提升其环境与资源效益。提出了包含捕集、封存、转化、分离系统的废弃煤矿巷道CO_(2)“封存-利用”一体化技术,基于几何相似理论与固体氧... 为应对全球二氧化碳减排的需求,探索利用废弃煤矿地下空间实现CO_(2)封存与资源化利用的新路径,以提升其环境与资源效益。提出了包含捕集、封存、转化、分离系统的废弃煤矿巷道CO_(2)“封存-利用”一体化技术,基于几何相似理论与固体氧化物电解池(SOEC)技术构建巷道反应硐室与实验室微型反应腔之间尺度映射关系,形成室内试验-井下应用的参数对应体系;通过开展恒电流共电解试验以及气相色谱对气体成分分析,系统揭示反应温度与CO_(2)/H_(2)O气体比例对CO_(2)转化效率的影响。结果表明:在保持A/V不变的条件下,巷道反应硐室尺寸为2.4 m×6 m×3.6 m,对应有效反应面积为384 m^(2);法拉第效率随着温度的升高呈现出“先下降后升高”的特征,随着CO_(2)/H_(2)O气体比例的增加而降低,CO_(2)转化率随着温度升高而显著提升,随着CO_(2)/H_(2)O气体比例增加而降低,在温度为850℃、气体比例CO_(2)∶H_(2)O=1∶1的共电解条件下,CO_(2)实现最优转化效率,转化率达72.22%,法拉第效率为61.77%。研究为实现废弃煤矿巷道CO_(2)封存与高值化利用提供了理论依据与技术支撑。 展开更多
关键词 废弃煤矿 固体氧化物电解池 CO_(2)/H_(2)O共电解 法拉第效率 CO_(2)转化率 相似理论
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基于拓扑图动力学模型的电力系统故障自动化检测系统
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作者 张锐 《电子设计工程》 2026年第1期59-65,共7页
为了及时对电力系统故障进行修复,设计了基于拓扑图动力学模型的电力系统故障自动化检测系统。所提系统以DSP为核心设计数据采集器,连接电力系统零序电流传感器采集实时电流。通过模数转换模块将电流信号数字化,并由ARM处理器存储和传... 为了及时对电力系统故障进行修复,设计了基于拓扑图动力学模型的电力系统故障自动化检测系统。所提系统以DSP为核心设计数据采集器,连接电力系统零序电流传感器采集实时电流。通过模数转换模块将电流信号数字化,并由ARM处理器存储和传输数据。故障诊断单元利用拓扑动力学模型生成电力系统拓扑图,并基于此建立多种故障检测模型,对输入的电流数据进行分析,识别不同类型的电力系统故障。实验结果表明,所提方法在小型、中型、大型配电网中的故障检测率均不低于90%,远高于其他方法。所提系统具备较为准确的电力系统电流信号模数转换能力,同时可有效生成电力系统拓扑图,并可自动化检测出当前电力系统不同故障类型,能够为电力系统的安全稳定运行提供有力保障。 展开更多
关键词 拓扑图 动力学模型 电力系统 自动化检测 模数转换单元 电流幅值
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Facile synthesis of Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)-Na_(2)Ni_(2)Ti_(6)O_(16)solid solutions for improving photocatalytic CO_(2)reduction
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作者 WANG Jingzhou YAO Chenzhong +2 位作者 ZHANG Xisheng MA Ziwei LI Linfeng 《燃料化学学报(中英文)》 北大核心 2026年第1期15-25,共11页
In this study,a straightforward one-step hydrothermal method was successfully utilized to synthesize the solid solution Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)-Na_(2)Ni_(2)Ti_(6)O_(16)(NNMTO-x),where x denotes the molar perce... In this study,a straightforward one-step hydrothermal method was successfully utilized to synthesize the solid solution Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)-Na_(2)Ni_(2)Ti_(6)O_(16)(NNMTO-x),where x denotes the molar percentage of Na_(2)Ni_(2)Ti_(6)O_(16)(NNTO)within Na_(0.9)Mg_(0.45)Ti_(3.55)O_(8)(NMTO),with x values of 10,20,30,40,and 50.Both XPS(X-ray Photoelectron Spectroscopy)and EDX(Energy Dispersive X-ray Spectroscopy)analyses unequivocally validated the formation of the NNMTO-x solid solutions.It was observed that when x is below 40,the NNMTO-x solid solution retains the structural characteristics of the original NMTO.However,beyond this threshold,significant alterations in crystal morphology were noted,accompanied by a noticeable decline in photocatalytic activity.Notably,the absorption edge of NNMTO-x(x<40)exhibited a shift towards the visible-light spectrum,thereby substantially broadening the absorption range.The findings highlight that NNMTO-30 possesses the most pronounced photocatalytic activity for the reduction of CO_(2).Specifically,after a 6 h irradiation period,the production rates of CO and CH_(4)were recorded at 42.38 and 1.47μmol/g,respectively.This investigation provides pivotal insights that are instrumental in the advancement of highly efficient and stable photocatalysts tailored for CO_(2)reduction processes. 展开更多
关键词 photocatalytic conversion hydrothermal method optical response range solid solution charge separation
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Three-dimensional Patterning Super-Black Silica-Based Nanocomposite Aerogels
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作者 Zhiyang Zhao Romain Civioc +13 位作者 Wei Liu Peiying Hu Mengmeng Li Fuhao Xu Robin Pauer Jiabei Luo Samuel Brunner PawełP.Ziemiański Ilia Sadykov Sandra Galmarini Yong Kong Xiaodong Shen Wim J.Malfait Shanyu Zhao 《Nano-Micro Letters》 2026年第2期1-18,共18页
Aerogels are ultra-lightweight,porous materials defined by a complex network of interconnected pores and nanostructures,which effectively suppress heat transfer,making them exceptional for thermal insulation.Furthermo... Aerogels are ultra-lightweight,porous materials defined by a complex network of interconnected pores and nanostructures,which effectively suppress heat transfer,making them exceptional for thermal insulation.Furthermore,their porous architecture can trap and scatter light via multiple internal reflections,extending the optical path within the material.When combined with suitable light-absorbing materials,this feature significantly enhances light absorption(darkness).To validate this concept,mesoporous silica aerogel particles were incorporated into a resorcinol-formaldehyde(RF)sol,and the silica-to-RF ratio was optimized to achieve uniform carbon compound coatings on the silica pore walls.Notably,increasing silica loading raised the sol viscosity,enabling formulations ideal for direct ink writing processes with excellent shape fidelity for super-black topographical designs.The printed silica-RF green bodies exhibited remarkable mechanical strength and ultra-low thermal conductivity(15.8 m W m^(-1) K^(-1))prior to pyrolysis.Following pyrolysis,the composites maintained structural integrity and printed microcellular geometries while achieving super-black coloration(abs.99.56%in the 280-2500 nm range)and high photothermal conversion efficiency(94.2%).Additionally,these silica-carbon aerogel microcellulars demonstrated stable electrical conductivity and low electrochemical impedance.The synergistic combination of 3D printability and super-black photothermal features makes these composites highly versatile for multifunctional applications,including on-demand thermal management,and efficient solar-driven water production. 展开更多
关键词 Super-black NANOCOMPOSITES AEROGEL 3D printing Photothermal conversion
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Hydrothermal conversion from hydrogarnet to hydroandradite based on alumina recovery from red mud
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作者 Hong-fei WU Xiao-lin PAN +3 位作者 Ji-long LIU Feng QIU Tun HE Hai-yan YU 《Transactions of Nonferrous Metals Society of China》 2026年第1期309-322,共14页
To synergistically recover alumina and alkali from red mud(RM),the structural stability and conversion mechanism of hydroandradite(HA)from hydrogarnet(HG)were investigated via the First-principles,XRF,XRD,PSD and SEM ... To synergistically recover alumina and alkali from red mud(RM),the structural stability and conversion mechanism of hydroandradite(HA)from hydrogarnet(HG)were investigated via the First-principles,XRF,XRD,PSD and SEM methods,and a novel hydrothermal process based on the conversion principle was finally proposed.The crystal structure simulation shows that the HA with varied silicon saturation coefficients is more stable than HG,and the HA with a high iron substitution coefficient is more difficult to be converted from HG.The(110)plane of Fe_(2)O_(3) is easier to combine with HG to form HA,and the binding energy is 81.93 kJ/mol.The effects of raw material ratio,solution concentration and hydrothermal parameters on the conversion from HG to HA were revealed,and the optimal conditions for the alumina recovery were obtained.The recovery efficiencies of alumina and Na_(2)O from the RM are 63.06%and 97.34%,respectively,and the Na_(2)O content in the treated RM is only 0.13%. 展开更多
关键词 HYDROGARNET hydroandradite structural stability hydrothermal conversion red mud
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A Synchronous Strategy to Zn-Iodine Battery by Polycationic Long-Chain Molecules
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作者 Da-Qian Cai Hengyue Xu +2 位作者 Tong Xue Jin-Lin Yang Hong Jin Fan 《Nano-Micro Letters》 2026年第1期80-94,共15页
Aqueous Zn-iodine batteries(ZIBs)face the formidable challenges towards practical implementation,including metal corrosion and rampant dendrite growth on the Zn anode side,and shuttle effect of polyiodide species from... Aqueous Zn-iodine batteries(ZIBs)face the formidable challenges towards practical implementation,including metal corrosion and rampant dendrite growth on the Zn anode side,and shuttle effect of polyiodide species from the cathode side.These challenges lead to poor cycle stability and severe self-discharge.From the fabrication and cost point of view,it is technologically more viable to deploy electrolyte engineering than electrode protection strategies.More importantly,a synchronous method for modulation of both cathode and anode is pivotal,which has been often neglected in prior studies.In this work,cationic poly(allylamine hydrochloride)(Pah^(+))is adopted as a low-cost dual-function electrolyte additive for ZIBs.We elaborate the synchronous effect by Pah^(+)in stabilizing Zn anode and immobilizing polyiodide anions.The fabricated Zn-iodine coin cell with Pah^(+)(ZnI_(2) loading:25 mg cm^(−2))stably cycles 1000 times at 1 C,and a single-layered 3.4 cm^(2) pouch cell(N/P ratio~1.5)with the same mass loading cycles over 300 times with insignificant capacity decay. 展开更多
关键词 Polyiodide shuttle effect Halogen battery Conversion cathode DENDRITES Polycation molecule
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Solar-Driven Redox Reactions with Metal Halide Perovskites Heterogeneous Structures
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作者 Qing Guo Jin‑Dan Zhang +1 位作者 Jian Li Xiyuan Feng 《Nano-Micro Letters》 2026年第2期337-367,共31页
Metal halide perovskites(MHPs)with striking electrical and optical properties have appeared at the forefront of semiconductor materials for photocatalytic redox reactions but still suffer from some intrinsic drawbacks... Metal halide perovskites(MHPs)with striking electrical and optical properties have appeared at the forefront of semiconductor materials for photocatalytic redox reactions but still suffer from some intrinsic drawbacks such as inferior stability,severe charge-carrier recombination,and limited active sites.Heterojunctions have recently been widely constructed to improve light absorption,passivate surface for enhanced stability,and promote charge-carrier dynamics of MHPs.However,little attention has been paid to the review of MHPs-based heterojunctions for photocatalytic redox reactions.Here,recent advances of MHPs-based heterojunctions for photocatalytic redox reactions are highlighted.The structure,synthesis,and photophysical properties of MHPs-based heterojunctions are first introduced,including basic principles,categories(such as Schottky junction,type-I,type-II,Z-scheme,and S-scheme junction),and synthesis strategies.MHPs-based heterojunctions for photocatalytic redox reactions are then reviewed in four categories:H2evolution,CO_(2)reduction,pollutant degradation,and organic synthesis.The challenges and prospects in solar-light-driven redox reactions with MHPs-based heterojunctions in the future are finally discussed. 展开更多
关键词 Metal halide perovskite HETEROJUNCTION Redox reaction Solar-to-chemical conversion
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Design and experimental validation of a low-impact wing locking/release mechanism based on energy conversion strategy
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作者 Yanbing Wang Honghao Yue +5 位作者 Jun Wu Xueting Pan Fei Yang Yong Zhao Jicheng Liu Xue Bai 《Defence Technology(防务技术)》 2026年第1期241-256,共16页
Conventional locking/release mechanisms often face challenges in aircraft wing separation processes,such as excessive impact loads and insufficient synchronization.These may cause structural damage to the airframe or ... Conventional locking/release mechanisms often face challenges in aircraft wing separation processes,such as excessive impact loads and insufficient synchronization.These may cause structural damage to the airframe or attitude instability,seriously compromising mission reliability.To address this engineering challenge,this paper proposes a multi-point low-impact locking/release mechanism based on the mobility model and energy conversion strategy.Through establishing a DOF constraint framework system,this paper systematically analyzes the energy transfer and conversion characteristics during the wing separation process,reveals the generation mechanism of impact loads,and conducts research on low-impact design based on energy conversion strategy.Building on this foundation,a single-point locking/release mechanism employing parallel trapezoidal key shaft structure was designed,which increases frictional contact time and reduces the energy release rate,thereby achieving low-impact characteristics.The mechanism's performance was validated through physical prototype development and systematic functional testing(including unlocking force,synchronization,and impact tests).Experimental results demonstrate:(1)Under 14 kN preload condition,the maximum unlocking force was only 92.54 N,showing a linear relationship with preload that satisfies the"strong-connection/weak-unlock"design requirement;(2)Wing separation was completed within 46 ms,with synchronization time difference among three separation mechanisms stably controlled within 12-14 ms,proving rapid and reliable operation;(3)The unlocking impact acceleration ranged between 26 and 73 g,below the 100 g design limit,confirming the effectiveness of the energy conversion strategy.The proposed low-impact locking/release mechanism design method based on energy conversion strategy resolves the traditional challenges of high impact and synchronization deficiencies.The synergistic optimization mechanism of"structural load reduction and performance improvement"provides a highly reliable technical solution for wing separable mechanisms while offering novel design insights for wing connection/separation systems engineering. 展开更多
关键词 Hypersonic vehicle Energy conversion strategy Low-impact Wing separation Locking/release mechanism
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Asymmetric Side‑Group Engineering of Nonfused Ring Electron Acceptors for High‑Efficiency Thick‑Film Organic Solar Cells
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作者 Dawei Li Nan Wei +11 位作者 Ya‑Nan Chen Xiaodong Wang Xu Han Ziqing Bian Xinyuan Zhang Zhe Zhang Wenkai Zhang Xinjun Xu Cuihong Li Yahui Liu Hao Lu Zhishan Bo 《Nano-Micro Letters》 2026年第3期227-239,共13页
A nonfused ring electron acceptor(NFREA),designated as TT-Ph-C6,has been synthesized with the aim of enhancing the power conversion efficiency(PCE)of organic solar cells(OSCs).By integrating asymmetric phenylalkylamin... A nonfused ring electron acceptor(NFREA),designated as TT-Ph-C6,has been synthesized with the aim of enhancing the power conversion efficiency(PCE)of organic solar cells(OSCs).By integrating asymmetric phenylalkylamino side groups,TT-Ph-C6 demonstrates excellent solubility and its crystal structure exhibits compact packing structures with a three-dimensional molecular stacking network.These structural attributes markedly promote exciton diffusion and charge carrier mobility,particularly advantageous for the fabrication of thick-film devices.TT-Ph-C6-based devices have attained a PCE of 18.01%at a film thickness of 100 nm,and even at a film thickness of 300 nm,the PCE remains at 14.64%,surpassing that of devices based on 2BTh-2F.These remarkable properties position TT-Ph-C6 as a highly promising NFREA material for boosting the efficiency of OSCs. 展开更多
关键词 Organic solar cells Nonfused ring electron acceptors ASYMMETRIC Power conversion efficiency
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“Proton‑Iodine” Regulation of Protonated Polyaniline Catalyst for High‑Performance Electrolytic Zn‑I_(2) Batteries
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作者 Mengyao Liu Kovan Khasraw Abdalla +8 位作者 Meng Xu Xueqian Li Runze Wang Qi Li Xiaoru Zhang Yanan Lv Yueyang Wang Xiaoming Sun Yi Zhao 《Nano-Micro Letters》 2026年第3期196-209,共14页
Low-cost and high-safety aqueous Zn-I_(2) batteries attract extensive attention for large-scale energy storage systems.However,polyiodide shuttling and sluggish iodine conversion reactions lead to inferior rate capabi... Low-cost and high-safety aqueous Zn-I_(2) batteries attract extensive attention for large-scale energy storage systems.However,polyiodide shuttling and sluggish iodine conversion reactions lead to inferior rate capability and severe capacity decay.Herein,a three-dimensional polyaniline is wrapped by carboxylcarbon nanotubes(denoted as C-PANI)which is designed as a catalytic cathode to effectively boost iodine conversion with suppressed polyiodide shuttling,thereby improving Zn-I_(2) batteries.Specifically,carboxyl-carbon nanotubes serve as a proton reservoir for more protonated-NH+=sites in PANI chains,achieving a direct I0/I−reaction for suppressed polyiodide generation and Zn corrosion.Attributing to this“proton-iodine”regulation,catalytic protonated C-PANI strongly fixes electrolytic iodine species and stores proton ions simultaneously through reversible-N=/-NH^(+)-reaction.Therefore,the electrolytic Zn-I_(2) battery with C-PANI cathode exhibits an impressive capacity of 420 mAh g^(−1) and ultra-long lifespan over 40,000 cycles.Additionally,a 60 mAh pouch cell was assembled with excellent cycling stability after 100 cycles,providing new insights into exploring effective organocatalysts for superb Zn-halogen batteries. 展开更多
关键词 Electrolytic Zn-I_(2)battery Proton-iodine regulation Direct I0/I−reaction conversion Limited polyiodide shuttling High performance
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面向移动机器人的多传感器紧耦合导航定位方法
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作者 陈路 谢维斯 +2 位作者 谭杰 陈丽竹 高勇 《电子科技大学学报》 北大核心 2026年第1期109-115,共7页
移动机器人依赖单一传感器往往难以克服光照变化、外部干扰、反射表面影响以及累积误差等问题,限制了环境感知能力和自身位姿测量的精度与可靠性。该文采用一种非线性优化的方法,实现(IMU、红外相机、RGB相机、激光雷达)数据层面紧耦合... 移动机器人依赖单一传感器往往难以克服光照变化、外部干扰、反射表面影响以及累积误差等问题,限制了环境感知能力和自身位姿测量的精度与可靠性。该文采用一种非线性优化的方法,实现(IMU、红外相机、RGB相机、激光雷达)数据层面紧耦合组合定位建图系统IIVL-LM。提出一种基于RGB图像信息的实时照度值转换模型,系统根据不同照度值通过非线性插值法输入视觉SLAM模型中进行实时建图,然后通过动态加权法对红外相机与RGB相机的关键帧特征提取融合。在模拟的室内救援场景数据集下,与多种主流融合定位方法相比,IIVL-LM在照度变化的苛刻条件下尤其是在低照度下性能提升明显,平均RMSE ATE提升了23%~39%(0.006~0.013)。IIVL-LM保证了系统始终会在不少于3个传感器有效的状态下进行,在确保精度的同时对未知开放场景有更强的鲁棒性,尤其对于室内救援这种复杂场景的应用具有一定的价值。 展开更多
关键词 移动机器人 多传感器融合 照度转换 非线性紧耦合 SLAM
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煤化工产业的高质量发展观
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作者 魏贤勇 宗志敏 +22 位作者 樊星 何晓燕 白翔 伊尔夏提·地里夏提 赵炜 倪中海 曹景沛 丛兴顺 赵云鹏 亢玉红 王爱民 高勇 莫文龙 徐美玲 梁静 赵小燕 柳方景 刘中秋 刘光辉 麻志浩 李胜 李莉 李壮 《石油学报(石油加工)》 北大核心 2026年第1期285-298,共14页
高质量发展应以最少的资源(特别是化石资源)消耗和最低的污染排放创造最大经济和社会效益,是中国经济社会长期发展的主旋律。作为中国目前的主要能源,煤炭在为国民经济的发展提供动力的同时也造成严重的环境污染,成为中国二氧化碳、硫... 高质量发展应以最少的资源(特别是化石资源)消耗和最低的污染排放创造最大经济和社会效益,是中国经济社会长期发展的主旋律。作为中国目前的主要能源,煤炭在为国民经济的发展提供动力的同时也造成严重的环境污染,成为中国二氧化碳、硫氧化物和氮氧化物排放的主要来源。煤中有机质富含芳环(特别是缩合芳环)和杂原子,作为洁净能源利用先天不足,但作为获取高值乃至高端化学品的原料利用得天独厚。现有煤化工产业高投入、高污染和低产出的生产模式难以为继,亟待转型。煤作为形成周期超过7000万年的不可再生化石资源,既不应简单焚烧,也不宜在苛刻条件和大量排放污染物的情况下转化成为低值产品。着力发展非化石能源替代以煤为主的化石能源是中国实现碳中和的根本出路。从煤中有机质的组成结构看,煤是获取特效药物和染料与高端功能性材料用的芳香族化合物(特别是缩合芳香族化合物)的重要原料。煤化工产业的高质量发展应遵循少用、精用和巧用原则,大力开发温和条件下定向转化煤中有机质为高端化学品的关键技术,形成煤炭资源高值化利用的产业链,助力国家整体的高质量发展。 展开更多
关键词 高质量发展 煤化工产业 温和条件 定向转化 高端化学品
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重组微小囊担子菌氨肽酶DmpA高效催化生产L-肌肽
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作者 孙晓瑄 张瑞婕 +3 位作者 孙雯 陈凌宇 朱显峰 张保国 《食品工业科技》 北大核心 2026年第1期226-235,共10页
本实验研究了一种来自微小囊担子菌MCA4210(Cystobasidium minutum MCA 4210)的氨肽酶基因dmpA催化合成L-肌肽的能力,构建基因工程菌株,以L-组氨酸和β-丙氨酸甲酯盐酸盐为底物催化合成L-肌肽,旨在提高L-肌肽的合成效率。将Cystobasidiu... 本实验研究了一种来自微小囊担子菌MCA4210(Cystobasidium minutum MCA 4210)的氨肽酶基因dmpA催化合成L-肌肽的能力,构建基因工程菌株,以L-组氨酸和β-丙氨酸甲酯盐酸盐为底物催化合成L-肌肽,旨在提高L-肌肽的合成效率。将Cystobasidium minutum MCA 4210来源的DmpA经密码子优化后在大肠杆菌BL21(DE3)(Escherichia coli BL21(DE3))中异源表达,并通过与麦芽糖结合蛋白(Maltose Binding Protein,MBP)进行融合表达提高目的蛋白可溶性表达和粗酶活性,构建重组菌株BL21(DE3)-MBP-DmpA,对重组菌株进行诱导表达条件和转化条件的探究。结果表明,实验成功将目的基因片段与MBP相连得到重组菌株BL21(DE3)-MBP-DmpA,经诱导条件优化粗酶活达到了145 U;经转化条件优化L-肌肽产量高达55.72 g/L,产率达54.54%。本研究将具有L-肌肽合成功能的Cystobasidium minutum MCA 4210来源的DmpA在大肠杆菌中异源表达,通过添加助溶标签和条件优化实现了L-肌肽的高效生产,所得L-肌肽的产量为目前报道最高,为基因工程菌工业化生产L-肌肽提供了实验基础,具有良好的应用前景。 展开更多
关键词 氨肽酶 DMPA L-肌肽 麦芽糖结合蛋白 异源表达 酶催化转化
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Zr掺杂SAPO-34的氧化物-分子筛双功能催化剂的制备及催化合成气制低碳烯烃性能
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作者 吴焜 郑和平 +2 位作者 梁洪 陈显坤 唐建华 《精细化工》 北大核心 2026年第1期155-163,共9页
通过水热合成法制备了Zr掺杂SAPO-34分子筛(ZrAPSO-xZr),将其与共沉淀法制备的ZnZrOz金属氧化物按质量比1∶1混合,制备了氧化物-分子筛双功能催化剂(ZnZrOz/ZrAPSO-xZr)。采用XRD、SEM、FTIR、BET、NH_(3)-TPD、Py-IR对ZrAPSO-xZr进行... 通过水热合成法制备了Zr掺杂SAPO-34分子筛(ZrAPSO-xZr),将其与共沉淀法制备的ZnZrOz金属氧化物按质量比1∶1混合,制备了氧化物-分子筛双功能催化剂(ZnZrOz/ZrAPSO-xZr)。采用XRD、SEM、FTIR、BET、NH_(3)-TPD、Py-IR对ZrAPSO-xZr进行了表征和测试。基于合成气〔n(H_(2))/n(CO)=2〕制备低碳烯烃工艺(STO),考察了Zr掺杂量〔x,其中n(Al_(2)O_(3))∶n(ZrO_(2))=1.0∶x,下同〕对ZnZrOz/ZrAPSO-xZr催化性能和寿命的影响。结果表明,Zr的掺杂提高了SAPO-34分子筛的比表面积(162.29 m^(2)/g),降低了其Brønsted酸(B酸)位点的密度(0.339μmol/m^(2)),使B酸位点的分布更分散,阻止了积炭阻塞分子筛孔道。ZrAPSO-xZr的最佳Zr掺杂量为0.10,ZrAPSO-0.10Zr的比表面积和B酸位点的密度分别达到441.88 m^(2)/g和0.269μmol/m^(2),其具有更多的酸位点(1.437 mmol/g)和更大的孔径(9.80 nm),这有利于为低碳烯烃提供足够的活性位点和传质空间。在n(H_(2))/n(CO)=2、反应温度400℃、反应压力3 MPa、气体体积空速为3000 mL/(g·h)(以催化剂质量计)的反应条件下,ZnZrOz/ZrAPSO-0.10Zr的最高低碳烯烃选择性为81.31%,反应2400 min时,其选择性(76.65%)稍降低。 展开更多
关键词 双功能催化剂 分子筛改性 SAPO-34 低碳烯烃 合成气转化 催化技术
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南海北部陆坡处沙波对内孤立波极性转换动力响应机制研究
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作者 任伯迁 王振鲁 +4 位作者 梁丙臣 谢波涛 吕英康 齐静静 徐兴雨 《海洋工程》 北大核心 2026年第1期35-48,共14页
南海北部陆坡130~310 m水深区域发育的沙波会在内孤立波的影响下发生迁移演化。基于MITgcm非静压数值模式构建了南海内孤立波数值模型,模拟了内孤立波的传播特征,发现内孤立波在南海北部陆坡区域发生了极性转换,模拟结果表明不同位置处... 南海北部陆坡130~310 m水深区域发育的沙波会在内孤立波的影响下发生迁移演化。基于MITgcm非静压数值模式构建了南海内孤立波数值模型,模拟了内孤立波的传播特征,发现内孤立波在南海北部陆坡区域发生了极性转换,模拟结果表明不同位置处不同极性内孤立波流速剖面的形态特征和海底流速方向存在较大差异。研究区域180 m水深处存在一个地形陡变的坡折,根据实测高精度水深数据,发现坡折以上较浅水域与坡折以下较深水域的沙波迁移方向相反。基于Delft3D数值模型,构建了垂向二维沙波迁移模型,结合内孤立波模型模拟的底层流速,选取研究区域内不同位置的典型沙波断面,分析了内孤立波作用下沙波迁移趋势。研究结果表明内孤立波极性转换是控制研究区域沙波迁移的重要因素,内孤立波沿大陆架传播浅化过程中下凹型内孤立波转变为上凸型内孤立波。下凹型内孤立波的底部流速为SE方向,海底沙波会受到沿陆坡向下的强流影响,导致水深较深海域的沙波向海迁移;上凸型内孤立波的底部流速为NW方向,海底沙波会遭受沿陆坡向上的强流影响,导致水深较浅海域的沙波向岸迁移。 展开更多
关键词 南海北部 沙波迁移 内孤立波 极性转换 MITgcm Delft3D
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