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冷却方式对B1800HS超高强钢热冲压组织性能的影响
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作者 顾艳峰 李晔 +5 位作者 宋燕利 路珏 刘艳雄 秦海 曾蔚 陈志勇 《机械工程材料》 北大核心 2026年第1期31-38,共8页
将B1800HS超高强钢加热至930℃保温5 min以确保完全奥氏体化,空冷至成形温度(750℃)后置于模具中保压2 s,分别空冷、油冷、模冷、水冷至室温(20℃),探究了冷却方式对试验钢组织和性能的影响规律以及钢的强塑性机理。结果表明:空冷、油... 将B1800HS超高强钢加热至930℃保温5 min以确保完全奥氏体化,空冷至成形温度(750℃)后置于模具中保压2 s,分别空冷、油冷、模冷、水冷至室温(20℃),探究了冷却方式对试验钢组织和性能的影响规律以及钢的强塑性机理。结果表明:空冷、油冷、模冷、水冷(冷却速率依次增大)下试样的显微组织分别为铁素体+粒状贝氏体、粒状贝氏体+马氏体、上贝氏体+粒状贝氏体+马氏体、马氏体。增加冷却速率可以显著细化马氏体板条,提高抗拉强度,但塑性损失较为明显;水冷方式下试样的抗拉强度最高,可达1 930 MPa,但断后伸长率仅为5.0%。油冷方式下试样中粒状贝氏体尺寸细小、分布均匀,可以分割并细化马氏体组织,使试验钢塑性和强度达到最佳的平衡;其抗拉强度相比于水冷方式仅略微降低,断后伸长率提高102%,强塑积达到最大,为17 412 MPa·%,综合力学性能最优。 展开更多
关键词 B1800hs超高强钢 冷却方式 力学性能 显微组织 粒状贝氏体
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A carbon sponge supporting a MoS_(2)-Mo_(2)C heterostructure as the Li_(2)S host for high-performance lithium sulfur batteries
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作者 Ji Yuanxiao Zhang Weiye +7 位作者 Xue Jiarui Zhang Jiyuan Ge Yunping Zhu Nan Jiang Ruibin Lei Zhibin Liu Zonghuai Sun Jie 《新型炭材料(中英文)》 北大核心 2026年第1期109-126,共18页
Despite their high theoretical capacity and energy density,lithiumsulfur(Li–S)batteries still face challenges such as soluble lithium polysulfides(LiPSs)shuttling and sluggish redox kinetics.In this work,we used a no... Despite their high theoretical capacity and energy density,lithiumsulfur(Li–S)batteries still face challenges such as soluble lithium polysulfides(LiPSs)shuttling and sluggish redox kinetics.In this work,we used a novel MoS_(2)-Mo_(2)C heterostructure anchored on a carbon sponge(CS)as a Li_(2)S host to solve these problems.A simple hydrothermal process following carbothermal reduction was used to construct the MoS_(2)-Mo_(2)C heterostructure,enabling control of the phases and integration of MoS_(2) and Mo_(2)C.Structural characterization confirmed the coherent interface of the heterostructure with a precise orientation relationship between the two phases and their uniform distribution.An evaluation of the adsorption and catalytic performance of the material showed that it has an exceptional LiPSs adsorption capacity with faster conversion from Li_(2)S_(4) to Li_(2)S_(2).Density functional theory calculations further confirmed these results.As a result,the cathode had a high initial discharge capacity of 693 mAh g^(−1) at 0.2 C and achieved stable cycling at 2 C for 500 cycles with a low decay rate of 0.107%per cycle.The heterostructure design,coupled with the macroporous CS framework,effectively prevented the shuttling and increased sulfur utilization,offering a promising way to produce practical high-energydensity Li–S batteries. 展开更多
关键词 Lithium-sulfur batteries heterostructure Carbon sponge Li_(2)S host Shuttle effect
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HS-SPME-GC-MS对不同品种大樱桃果实香气成分分析
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作者 周一帆 郭志刚 +3 位作者 马新院 谭维军 陶淑芸 韩松凌 《寒旱农业科学》 2026年第3期245-254,共10页
探讨天水地区大樱桃香气成分差异,为甜樱桃优良品种的香味遗传育种、香气合成代谢、分子生物学研究方面提供理论依据。以天水地区主栽的7个大樱桃品种为试材,使用顶空固相微萃取气相色谱质谱联用技术(HS-SPME-GC-MS)鉴定果实中存在的香... 探讨天水地区大樱桃香气成分差异,为甜樱桃优良品种的香味遗传育种、香气合成代谢、分子生物学研究方面提供理论依据。以天水地区主栽的7个大樱桃品种为试材,使用顶空固相微萃取气相色谱质谱联用技术(HS-SPME-GC-MS)鉴定果实中存在的香气物质,应用TIC峰面积归一法测定了各成分的相对含量。结果表明,7个大樱桃品种中共检出77种香气物质,其中布鲁克斯有24种、含香有25种、美早有16种、萨米脱有26种、拉宾斯有35种、斯坦勒有14种、红灯有12种。7个大樱桃品种果实香气物质含量各有差异,其中红灯醇类物质含量最高,为432.4g/kg;斯坦勒酯类物质含量最高,为2.26%;含香醛类物质含量最高,为488.8 g/kg;布鲁克斯酮类物质含量最高,为68.8 g/kg;其他类物质拉宾斯含量最高,为255.8 g/kg。7个大樱桃共有的物质为苯甲醛,被认定为关键香气成分;特有香气物质拉宾斯11种、布鲁克斯10种、萨米脱9种、含香7种、斯坦勒3种、美早2种。 展开更多
关键词 大樱桃 hs-SPME-GC-MS 香气成分 品种
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Atomic-scale characterization of epitaxial Bi(110)/VTe_(2) bilayer heterostructure
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作者 WANG Qiwei LI Shaochun 《物理学进展》 北大核心 2026年第1期13-21,共9页
Interplay between topology and magnetism can give rise to exotic properties in topological materials.Two-dimensional bismuth has been extensively studied owing to its topological states with a strong spin-orbit coupli... Interplay between topology and magnetism can give rise to exotic properties in topological materials.Two-dimensional bismuth has been extensively studied owing to its topological states with a strong spin-orbit coupling,and 1T-VTe_(2)monolayer theoretically predicted to host an intrinsic magnetism as experimentally suggested.In this work,we successfully constructed a vertical heterostructure composed of the two-dimensional Bi(110)monolayer and 1T-VTe_(2)monolayer by using molecular beam epitaxy(MBE).Scanning tunneling microscopy(STM)measurements revealed that the growth of Bi preferably occurs along the step edges of the VTe_(2)monolayer,forming a Bi(110)monolayer on top of the VTe_(2)monolayer next to a peripheral Bi bilayer.The Bi(100)/VTe_(2)heterostructure exhibits a specific lattice registry with a well-defined moiréperiodicity.Scanning tunneling spectroscopy(STS)measurements further unveiled an universal suppression in the local density-of-states at the boundary of the Bi(110)/VTe_(2)bilayer.By examining the atomic structures of Bi(110)boundaries,we found this effect does not originate from the previously proposed atomic reconstruction at the step edge of Bi(110),but is likely related to the magnetic properties of the VTe_(2)monolayer. 展开更多
关键词 Bi/VTe_(2)heterostructure moirépattern edge state molecular beam epitaxy scanning tunneling microscopy
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Interfacial Superconductivity in the Type-Ⅲ Heterostructure SnSe_(2)/PtTe_(2)
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作者 Jun Fan Xiao-Le Qiu +2 位作者 Ben-Chao Gong Kai Liu Zhong-Yi Lu 《Chinese Physics Letters》 2026年第1期248-264,共17页
Interfacial superconductivity(IS)has been a topic of intense interest in condensed matter physics,due to its unique properties and exotic photoelectrical performance.However,there are few reports about IS systems cons... Interfacial superconductivity(IS)has been a topic of intense interest in condensed matter physics,due to its unique properties and exotic photoelectrical performance.However,there are few reports about IS systems consisting of two insulators.Here,motivated by the emergence of an insulator-metal transition in type-Ⅲ heterostructures and the superconductivity in some“special”two-dimensional(2D)semiconductors via electron doping,we predict that the 2D heterostructure SnSe_(2)/PtTe_(2) is a model system for realizing IS by using firstprinciples calculations.Our results show that due to slight but crucial interlayer charge transfer,SnSe_(2)/PtTe_(2) turns to be a type-Ⅲ heterostructure with metallic properties and shows a superconducting transition with the critical temperature(T_(c))of 3.73 K.Similar to the enhanced electron–phonon coupling(EPC)in the electrondoped SnSe_(2) monolayer,the IS in the SnSe_(2)/PtTe_(2) heterostructure mainly originates from the metallized SnSe_(2) layer.Furthermore,we find that its superconductivity is sensitive to tensile lattice strain,forming a domeshaped superconducting phase diagram.Remarkably,at 7%biaxial tensile strain,the superconducting T_(c) can increase more than twofold(8.80 K),resulting from softened acoustic phonons at the𝑀point and enhanced EPC strength.Our study provides a concrete example for realizing IS in type-Ⅲ heterostructures,which waits for future experimental verification. 展开更多
关键词 d heterostructure condensed matter type III heterostructure PtTe interfacial superconductivity SnSe electron dopingwe first principles calculations
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Growth of Ce-doped NiCo-LDHs on tin dioxide-modified nickel foam as oxygen evolution reaction catalyst electrode
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作者 Zhongjie Song Nannan Zhang +3 位作者 Jun Yu Huiyu Sun Zhengying Wu Yukou Du 《Chinese Chemical Letters》 2026年第1期689-695,共7页
Developing catalysts with excellent stability while significantly reducing the overpotential of the oxygen evolution reaction(OER) is crucial for advancing overall water splitting(OWS) systems.In this study,we synthes... Developing catalysts with excellent stability while significantly reducing the overpotential of the oxygen evolution reaction(OER) is crucial for advancing overall water splitting(OWS) systems.In this study,we synthesized the electrode material Ce-NiCo-LDHs@SnO_(2)/NF through a two-step hydrothermal reaction,where Ce-doped NiCo-LDHs are grown on nickel foam modified by a SnO_(2) layer.Ce doping adjusts the internal electronic distribution of Ni Co-LDHs,while the introduction of the SnO_(2) layer enhances electron transfer capability.Together,these factors contribute to the reduction of the OER energy barrier and experimental evidence confirms that the reaction proceeds via the lattice oxygen evolution mechanism(LOM).Consequently,Ce-NiCo-LDHs@SnO_(2)/NF exhibits high level electrochemical performance in OER,requiring only 234 m V overpotential to achieve a current density of 10 m A/cm^(2),with a Tafel slope of just 27.39 m V/dec.When paired with Pt/C/NF,an external potential of only 1.54 V is needed to drive OWS to attain a current density amounting to 10 m A/cm^(2).Furthermore,the catalyst demonstrates stability for 100 h during the OWS stability test.This study underscores the feasibility of enhancing the OER performance through Ce doping and the introduction of a conductive SnO_(2) layer. 展开更多
关键词 Oxygen evolution reaction heterostructure DOPING Conductive layer
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Realization of Polytype Heterostructures via Delicate Structural Transitions from a Doped Mott Insulator
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作者 Yanyan Geng Manyu Wang +9 位作者 Shumin Meng Shuo Mi Chang Li Huiji Hu Jianfeng Guo Rui Xu Fei Pang Wei Ji Weichang Zhou Zhihai Cheng 《Chinese Physics Letters》 2026年第3期118-135,共18页
Transition-metal dichalcogenides hosting multiple competing structural and electronic phases are thus ideal platforms for constructing polytype heterostructures with emergent quantum properties.However,controlling pha... Transition-metal dichalcogenides hosting multiple competing structural and electronic phases are thus ideal platforms for constructing polytype heterostructures with emergent quantum properties.However,controlling phase transitions to form diverse heterostructures inside a single crystal remains challenging.In this study,we realize vertical/lateral polytype heterostructures in a hole-doped Mott insulator via thermal annealing-induced structural transitions.Raman spectroscopy,atomic force microscopy and scanning Kelvin probe force microscopy confirm the coexistence of T-H polytype heterostructures.Atomic-scale scanning tunneling microscopy/spectroscopy measurements reveal the transparent effect in 1H/1T vertical heterostructures,where positive bias voltage induces in a pronounced superposition of the√13×√13 CDW of the 1T-layer on the 1H-layer.By systematically comparing the 1T/1H and 1T/1T interfaces,we demonstrate that the metallic 1H-layer induces a Coulomb screening effect on the 1T-layer,suppressing the formation of CDW domain walls and forming more ordered electronic states.These results clarify the interfacial coupling between distinct quantum many-body phases and establish a controllable pathway for constructing two-dimensional polytype heterostructures with tunable electronic properties. 展开更多
关键词 Raman spectroscopy polytype heterostructures structural electronic phases spectroscopyatomic force microscopy thermal annealing structural transitions emergent quantum propertieshowevercontrolling phase transitions constructing polytype heterostructures
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Halide Perovskite Heterostructures for High-Performance Light-Emitting Diodes
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作者 Yiming Huo Tingwei He +2 位作者 Shaopeng Yang Yuanzhi Jiang Changjiu Sun 《Nano-Micro Letters》 2026年第6期222-252,共31页
Metal halide perovskites have emerged as highly promising candidates for the emissive layer in next-generation light-emitting diodes(LEDs)due to their narrow emission linewidths,high photoluminescence quantum yields,a... Metal halide perovskites have emerged as highly promising candidates for the emissive layer in next-generation light-emitting diodes(LEDs)due to their narrow emission linewidths,high photoluminescence quantum yields,and tunable emission wavelengths.Achieving high-performance perovskite LEDs(Pe LEDs)requires the emissive layer to possess efficient radiative recombination,low defect density,minimal ion mobility,and effective carrier confinement.Perovskite/perovskite heterostructure(PPHS)offers a compelling approach for engineering emissive layers with these desired attributes,owing to their ability to passivate surface defects,tailor bandgaps,and suppress ion migration.Pe LEDs based on PPHS have demonstrated superior performance compared to single-phase devices,particularly in terms of external quantum efficiency and operational stability.This review provides a comprehensive overview of the typical PPHS architectures applied in Pe LEDs,including vertical,lateral,and bulk configurations.We discuss representative fabrication strategies and the associated optoelectronic properties of these heterostructures,highlighting the mechanisms by which they enhance device efficiency and stability.Finally,we explore the remaining challenges and prospects for the application of PPHS in Pe LEDs and other luminescent technologies. 展开更多
关键词 Halide perovskite heterostructure ELECTROLUMINESCENCE Perovskite light-emitting diode
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Nanodot-heterostructure-engineered cathode-electrolyte interphase for stable lithium-rich manganese-based oxide cathodes
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作者 Xu Xue Chenchen Li +5 位作者 Shengnan He Liaona She Fulai Qi Zhijun Wu Mingxia Gao Hongge Pan 《Journal of Energy Chemistry》 2026年第2期136-145,I0005,共11页
High-voltage Li-rich Mn-based oxide(LRMO)cathodes are promising for breaking through the energy density limits of lithium-ion batteries,yet their practical application remains limited by electrochemical performance de... High-voltage Li-rich Mn-based oxide(LRMO)cathodes are promising for breaking through the energy density limits of lithium-ion batteries,yet their practical application remains limited by electrochemical performance degradation caused by unstable cathode-electrolyte interphase(CEI)evolution during longterm cycling.To address this issue,we propose a novel surface modification strategy using La_(0.7)Sr_(0.3)MnO_(3-σ)(LSMO)nanodots,which exhibit high electronic co nductivity and excellent corrosion resistance.These nanodots act as stable anchoring sites,facilitating the formation of a robust CEI on LRMO,The LSMOmodified cathode demonstrates significantly improved anionic redox reversibility,effectively mitigating transition metal migration and lattice oxygen loss.Furthermore,the optimized interfacial electrochemical kinetics ensure sustained rapid Li+diffusion throughout cycling,while the formation of a stable trilayer CEI structure suppresses electrolyte decomposition.Benefiting from these synergistic effects,the LSMO nanodot-engineered LRMO cathode delivers outstanding cycling stability,retaining 97.4%capacity after 300 cycles at 1 C.This work not only highlights the critical role of nanodot heterostructures in stabilizing CEI but also provides a new approach to designing high-voltage cathodes with superior interfacial compatibility and long-term durability. 展开更多
关键词 Lithium-rich cathode Cathode-electrolyte interphase heterostructures Diffusion kinetics High voltage
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基于HS-GC-IMS技术解析不同干燥工艺对西红花挥发性成分的影响
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作者 王嘉习 吴凤云 +7 位作者 张弛 骆紫义 洪丹尧 高爽 栾洁 巴剑波 陆颖洁 韩婷 《分析测试学报》 北大核心 2026年第1期50-60,共11页
该研究通过顶空-气相色谱-离子迁移谱(HS-GC-IMS)技术,对西红花鲜样和不同干燥方法(阴干、加热板干燥、烘箱干燥、真空干燥及冻干)样品中的75个挥发性化合物进行定性和相对定量分析,并构建了西红花挥发性成分的指纹图谱。通过聚焦于西... 该研究通过顶空-气相色谱-离子迁移谱(HS-GC-IMS)技术,对西红花鲜样和不同干燥方法(阴干、加热板干燥、烘箱干燥、真空干燥及冻干)样品中的75个挥发性化合物进行定性和相对定量分析,并构建了西红花挥发性成分的指纹图谱。通过聚焦于西红花不同干燥过程中挥发性成分的动态变化,运用主成分分析、偏最小二乘判别分析和聚类热图对样品进行识别和差异性分析,筛选出27种关键差异化合物,解析不同干燥工艺对西红花中挥发性成分的影响,揭示了不同干燥方法通过不同程度作用于西红花中物理(高温挥发)、化学(光热分解)、生化反应影响西红花中的挥发性成分,造成西红花药材品质的多样性。阴干样本中的挥发性成分种类最丰富,加热板干燥样本中的藏红花醛含量最高(2.91 mg/g),烘箱和真空干燥样本中的酯类和酮类丰度最高,冻干样本中的成分稳定性最高。研究可为未来根据实际应用场景选择不同的干燥方法提供理论指导。 展开更多
关键词 西红花 干燥工艺 挥发性成分 顶空-气相色谱-离子迁移谱 藏红花醛
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Reversible construction of rigid-flexible layered-tunnel heterostructures endowing MnO_(2) cathode with robust zinc ion storage
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作者 Zhuoyun Song Mingjun Cui +7 位作者 Yiguo Zhang Nan Zhang Haotian Yang Kangrui Ren Lang Chen Zong-Lin Liu Ying Xie Ting-Feng Yi 《Journal of Energy Chemistry》 2026年第3期835-847,共13页
MnO_(2) emerges as a promising cathode material for aqueous zinc-ion batteries(AZIBs)due to its high theoretical capacity and ideal working voltage.However,inherent limitations in low electrical conductivity and struc... MnO_(2) emerges as a promising cathode material for aqueous zinc-ion batteries(AZIBs)due to its high theoretical capacity and ideal working voltage.However,inherent limitations in low electrical conductivity and structural instability restrict its widespread application.Herein,we fabricated layered δ-MnO_(2) and introduced Cu and Ce metal ions for structural regulation,thus constructing a δ/a-MnO_(2) heterostructure within the δ-MnO_(2) matrix,forming a heterointerface that simultaneously enhances the electrical conductivity and structural stability of the material.In this system,Cu^(2+)acts as a catalyst,promoting the reduction of high-valent Mn to Mn^(2+)and enabling local two-electron transfer,which significantly increases the discharge specific capacity of MnO_(2).For Ce^(3+),it functions as a structural regulator,inducing the partial transformation of δ-MnO_(2) to a-MnO_(2) and forming the δ/a-MnO_(2) heterostructure.Further supported by density functional theory(DFT)calculations and in-situ characterization results,the heterointerface between a-MnO_(2) andδ-MnO_(2) generates an internal electric field due to the difference in Fermi levels.This not only effectively enhances the electron transfer capability but also significantly improves structural stability.Benefiting from these advantages,the Cu,Ce co-incorporated MnO_(2)(CCMO)cathode delivers a high discharge capacity of 455.4 mAh g^(-1)at 0.2 A g^(-1)and maintains 191.2 mAh g^(-1)specific capacity after 1500 cycles with 95%capacity retention at 2 A g^(-1),which is significantly better than non-doped MnO_(2).This strategy of structural regulation and heterostructure construction using vip ions offers a new approach for developing high-performance Mn-based cathode materials for AZIBs. 展开更多
关键词 Aqueous zinc-ion battery MnO_(2) heterostructure Zinc ions storage
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大语言模型驱动的HS编码智能匹配系统——WTO/TBT-SPS通报数据的多国家产品匹配研究
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作者 孙芳芳 王绍岩 +2 位作者 王泽平 王若溪 卓毓滢 《中国科技信息》 2026年第2期84-86,共3页
1背景。国际贸易一直是刺激世界经济增长的重要动力,国际贸易的国际化和统一化是国际贸易的重要研究课题。目前全球贸易正朝着数字化方向发展,商品分类统一化逐步成为推动国际贸易规则新的重要基石。Verified Market Research发布报告,... 1背景。国际贸易一直是刺激世界经济增长的重要动力,国际贸易的国际化和统一化是国际贸易的重要研究课题。目前全球贸易正朝着数字化方向发展,商品分类统一化逐步成为推动国际贸易规则新的重要基石。Verified Market Research发布报告,全球跨境电商市场规模在2024年突破1.245万亿美元,年平均增长率为18.7%。在国际贸易治理体系当中,世界贸易组织(WTO)建立了技术性贸易措施(TBT)与卫生和植物卫生措施(SPS)通报体系,这两项措施成为国际技术贸易透明化的保障。目前,在全球贸易一体化发展进程中,技术性贸易措施日渐成为主要的非关税贸易壁垒,世界银行指出技术贸易措施问题已经超越了关税而成为影响国际贸易的主要壁垒,在过去技术性贸易措施对全球贸易造成的影响要比关税平均高出5%~10%。据商务部《中国技术性贸易措施年度报告(2023)》显示,我国由于技术性贸易壁垒造成的损失已达800亿美元以上。 展开更多
关键词 WTO 跨境电商 hs编码 技术性贸易壁垒
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Enhancing Heat Transfer in X-ray Tube by van der Waals Heterostructures-based Thermionic Emission
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作者 LI Qian-qian HUANG Sun-chao +8 位作者 CHEN Su-guo WANG Yue SHI Xi-hang ZHANG Xiao-qiu-yan HU Min ZHANG Ping WANG Shao-meng ZHANG Chao GONG Yu-bin 《真空电子技术》 2026年第1期21-27,共7页
Van der Waals(vdW)heterostructures have attracted much attention due to their distinctive optical,electrical,and thermal properties,demonstrating promising potential in areas such as photocatalysis,ultrafast photonics... Van der Waals(vdW)heterostructures have attracted much attention due to their distinctive optical,electrical,and thermal properties,demonstrating promising potential in areas such as photocatalysis,ultrafast photonics,and free electron radiation devices.Particularly,they are promising platforms for studying thermionic emission.It is illustrated that using vdW heterostructure-based thermionic emission can enhance heat transfer in vacuum devices.As a proof of concept,the approach is demonstrated to offer a promising solution for the long-standing overheating issue in X-ray tubes.Specifically,it is shown that the saturated target temperature of a 2000 W X-ray tube can be reduced from around 1200℃ to 490℃.Additionally,it is also demonstrated that by reducing the height of the Schottky barrier formed in the vdW heterostructures,the thermionic cooling performance can be enhanced.The findings pave the way for the development of high-power X-ray tubes. 展开更多
关键词 X-ray tube Heat transfer Thermionic emission Thermionic cooling Van der Waals heterostructures
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Bonding heterostructure mediated“photo-thermo-electric”implant:NIR-Ⅱphotothermal and thermoelectric therapy for bone tumor defects
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作者 Jun Zan Jiachi Zhao +4 位作者 Jie Zeng Qian Yang Hengyun Ye Youwen Yang Cijun Shuai 《Bio-Design and Manufacturing》 2026年第1期165-181,I0030,共18页
Recurrence of solid tumors after surgical resection is a major barrier to tissue regeneration.As an emerging treatment strategy,photo-thermo-electric therapy ablates tumor cells via photothermal effects and generates ... Recurrence of solid tumors after surgical resection is a major barrier to tissue regeneration.As an emerging treatment strategy,photo-thermo-electric therapy ablates tumor cells via photothermal effects and generates reactive oxygen species(ROS)via thermoelectric effects to disrupt heat shock proteins,thereby suppressing their protective function in tumor cells.However,conventional materials suffer from low thermoelectric efficiency and weak tissue penetration ability.In this study,we fabricated iodine-doped bismuth sulfide(I-Bi_(2)S_(3))nanorods with bonding heterostructures to improve thermoelectric performance.The approach employed iodine doping to introduce additional electrons,thereby regulating the band structure of Bi_(2)S_(3)and exploiting the dual low-energy vibration effect of the heterostructures to reduce thermal conductivity.More importantly,controlling the type of heterostructure modulated the bandgap width,thereby expanding the light absorption range to the higher-penetration near-infrared(NIR)-Ⅱregion for deep tissue treatment.The I-Bi_(2)S_(3)nanorods were incorporated into poly-L-lactic acid(PLLA)scaffolds to confer antitumor functionality.According to the results,the bonding heterostructures enhanced the conductivity of Bi_(2)S_(3)and reduced its thermal conductivity,significantly enhancing thermoelectric efficacy.The heterostructures reduced the bandgap of Bi_(2)S_(3)from 1.23 to 0.88 eV,enabling optical absorption in the NIR-Ⅱregion.The ROS tests showed that the PLLA/I-Bi_(2)S_(3)scaffold exhibited good photothermal effects and ROS generation under 1064-nm laser irradiation.The antitumor efficacy of the PLLA/I-Bi_(2)S_(3)scaffold reached 84.6%against MG-63 cells,demonstrating its exceptional potential in cancer treatment. 展开更多
关键词 Antitumor bone scaffolds Photo-thermo-electric therapy Near-infraredⅡwindow Bonding heterostructures Selective laser sintering
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HS-SPME-GC-MS分析香菇牛肉酱的挥发性风味成分
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作者 王磊 杨琪 +2 位作者 刘长姣 刘桐汐 陈宇飞 《中国调味品》 北大核心 2026年第2期244-248,共5页
以香菇牛肉酱为研究对象,采用顶空固相微萃取-气质联用法(HS-SPME-GC-MS)对其挥发性风味成分进行分离和鉴定,通过单因素试验和响应面试验分别考察萃取样品量、萃取温度、萃取时间对挥发性风味成分的影响。结果表明,萃取样品量1.9 g、萃... 以香菇牛肉酱为研究对象,采用顶空固相微萃取-气质联用法(HS-SPME-GC-MS)对其挥发性风味成分进行分离和鉴定,通过单因素试验和响应面试验分别考察萃取样品量、萃取温度、萃取时间对挥发性风味成分的影响。结果表明,萃取样品量1.9 g、萃取温度45℃、萃取时间36 min为较优的萃取条件。在此条件下,鉴定出香菇牛肉酱中挥发性风味成分61种,占总挥发性成分的92.67%,主要包括烃类25种、醇类11种、酯类5种、醛类7种、其他类(醚类、硫化物、苯环类等)13种。该研究结果为香菇牛肉酱风味和品质的调控和精深加工提供了参考。 展开更多
关键词 香菇牛肉酱 hs-SPME GC-MS 挥发性风味成分
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Tandem catalysis over Cu@Co/CoFe-P metal-alloy heterostructure achieving ampere-level nitrate-to-ammonia electrosynthesis
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作者 Laiji Xu Wei Guo +4 位作者 Simeng Yu Zhenlin Mo Jiangzhou Qin Yiwen Chen Baojun Liu 《Journal of Energy Chemistry》 2026年第1期329-338,I0008,共11页
The electrocatalytic reduction of nitrate to ammonia(NO_(3)^(−)RR)offers a sustainable alternative to energy-intensive industrial NH3 synthesis.Tandem catalysis has shown promise in overcoming the multi-step complexit... The electrocatalytic reduction of nitrate to ammonia(NO_(3)^(−)RR)offers a sustainable alternative to energy-intensive industrial NH3 synthesis.Tandem catalysis has shown promise in overcoming the multi-step complexity of NO_(3)^(−)RR,yet challenges remain in optimizing performance and elucidating tandem mechanisms.Herein,we report a Cu@Co/CoFe-P tandem electrocatalyst featuring a phosphorus-doped heterostructure with dual active sites(Cu-P and Co/CoFe-P).This catalyst achieves an exceptional NH_(3)yield of 175.40 mg h^(−1)cm^(−2)and a record-high current density exceeding 2 A cm^(−2),with the electro-synthesized NH3 directly converted into NH4Cl.In situ spectroscopic analysis and density functional theory(DFT)calculations reveal a novel desorption-reactivation tandem mechanism:(1)the Cu-P domain preferentially reduces NO_(3)^(−)to*NO_(2),which desorbs as stable NO_(2)^(−);(2)the Co/CoFe-P domain subsequently reactivates NO_(2)^(−),and converts it efficiently into NH3.Moreover,phosphorus doping enhances*H supply,while Fe alloying with Co promotes NO_(2)^(−)hydrogenation,ensuring an efficient and synchronized tandem pathway for NO_(3)^(−)RR.The proposed*NO_(2)desorption-reactivation mechanism deepens the understanding of NO_(3)^(−)RR tandem process,thereby paving the way for designing more efficient tandem electrocatalysts. 展开更多
关键词 Nitrate reduction to ammonia Tandem catalysis Metal-alloy heterostructure Ampere-level current density Ammonia recovery
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Magnetic-Dielectric Synergy in One-Dimensional Metal Heterostructures for Enhanced Low-Frequency Microwave Absorption
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作者 Feiyue Hu Peigen Zhang +10 位作者 Pei Ding Shuo Zhang Bingbing Fan Ali Saffar Shamshirgar Wei Zheng Wenwen Sun Longzhu Cai Haijiao Xie Qiyue Shao Johanna Rosen ZhengMing Sun 《Nano-Micro Letters》 2026年第5期371-390,共20页
Microwave absorption(MA)materials often face poor synergy between impedance matching and attenuation in the low-frequency range.Balancing permittivity and permeability through magnetic-dielectric synergy is a promisin... Microwave absorption(MA)materials often face poor synergy between impedance matching and attenuation in the low-frequency range.Balancing permittivity and permeability through magnetic-dielectric synergy is a promising strategy to address this issue.To realize the synergy,herein,Sn whiskers with an in situ oxide layer served as substrates for magnetic-loss-active CoNi nanosheet growth,forming a hierarchical CoNi@SnO_(2)@Sn(CNS)heterostructure.The CNS absorber achieves a minimum reflection loss(RL_(min))value of-62.29 dB with an effective absorption bandwidth(EAB)of 2.2 GHz,covering the entire C-band with 70%absorption at only 2.61 mm thickness.The nanosheet design of CoNi enhances magnetic anisotropy to promote natural resonance,while the conductive Sn core and abundant Sn/SnO_(2) and CoNi/SnO_(2) heterointerfaces facilitate conduction loss and dielectric polarization.When composited into a thermoplastic polyurethane(TPU)matrix,the resulting CNS/TPU-2 film(20 wt%CNS)exhibits an RL_(min) value of-61.04 dB and a 2.5 GHz EAB.Its in-plane and through-plane thermal conductivities reach 2.41 and 0.51 W m^(-1) K^(-1),representing 4.1 and 2.6 times those of pure TPU films,respectively,facilitating heat dissipation from protected devices.This work provides valuable insights into magnetic-dielectric synergy for low-frequency MA of 1D metal-based materials,offering promising potential for 5G communications and flexible electronics. 展开更多
关键词 Low frequency microwave absorption Magnetic-dielectric synergy MAX phase CoNi@SnO_(2)@Sn heterostructure Thermal conductivity
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基于HS-SPME-GC-MS技术的6种香型白酒中挥发性化合物差异分析
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作者 胡晓龙 李华 +5 位作者 雷旭东 韩素娜 张俊飞 邓鸣东 黄润娜 王晓毅 《轻工学报》 北大核心 2026年第1期1-15,共15页
【目的】进一步明晰4种基本香型和2种融合香型白酒挥发性化合物特征、关键香气及差异成分。【方法】采用顶空-固相微萃取-气相色谱-质谱联用(HS-SPME-GC-MS)技术、相对气味活度值(ROAV)法及正交偏最小二乘判别分析(OPLS-DA)法,对4种基... 【目的】进一步明晰4种基本香型和2种融合香型白酒挥发性化合物特征、关键香气及差异成分。【方法】采用顶空-固相微萃取-气相色谱-质谱联用(HS-SPME-GC-MS)技术、相对气味活度值(ROAV)法及正交偏最小二乘判别分析(OPLS-DA)法,对4种基本香型和2种融合香型白酒的挥发性化合物分布特征、关键香气成分及重要差异化合物进行分析。【结果】6种香型白酒中共鉴定出207种挥发性化合物,涵盖10个类别,主要为酯类、芳香族类、醇类、烯类、醛类和酮类化合物,且各香型白酒中的挥发性化合物组成差异明显,其中存在于所有香型、单一香型及2~5种香型白酒中的挥发性化合物分别为26种、77种及104种;清香型和米香型白酒中的挥发性化合物种类较少;陶融香型和兼香型白酒在挥发性化合物组成上均与浓香型和酱香型白酒更为相似。此外,己酸乙酯、辛酸乙酯、苯乙酸乙酯等10种挥发性化合物为1种或多种香型白酒的关键香气化合物;己酸乙酯、十四酸乙酯、十六酸乙酯、乙酸乙酯等13种挥发性化合物为区分6种香型白酒的重要差异挥发性化合物。【结论】不同香型白酒挥发性化合物组成存在明显差异,其关键香气化合物与差异化合物均以乙酯类为主,基本香型白酒工艺的科学融合是研制创新香型白酒的重要技术路径。 展开更多
关键词 白酒香型 顶空-固相微萃取-气相色谱-质谱联用技术 挥发性化合物 差异分析
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Ultra-fast and high-responsivity self-powered vis-NIR photodetector via surface charge transfer doping in MoTe_(2)/ReS_(2)heterostructures
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作者 Haozhe Ruan Yongkang Liu +5 位作者 Jianyu Wang Linjiang Xie Yixuan Wang Mengting Dong Zhangting Wu Liang Zheng 《Journal of Semiconductors》 2026年第1期99-106,共8页
The development of optoelectronic technologies demands photodetectors with miniaturization,broadband operation,high sensitivity,and low power consumption.Although 2D van der Waals(vd W)heterostructures are promising c... The development of optoelectronic technologies demands photodetectors with miniaturization,broadband operation,high sensitivity,and low power consumption.Although 2D van der Waals(vd W)heterostructures are promising candidates due to their built-in electric fields,ultrafast photocarrier separation,and tunable bandgaps,defect states limit their performance.Therefore,the modulation of the optoelectronic properties in such heterostructures is imperative.Surface charge transfer doping(SCTD)has emerged as a promising strategy for non-destructive modulation of electronic and optoelectronic characteristics in two-dimensional materials.In this work,we demonstrate the construction of high-performance p-i-n vertical heterojunction photodetectors through SCTD of MoTe_(2)/ReS_(2)heterostructure using p-type F_(4)-TCNQ.Systematic characterization reveals that the interfacial doping process effectively amplifies the built-in electric field,enhancing photogenerated carrier separation efficiency.Compared to the pristine heterojunction device,the doped photodetector exhibits remarkable visible to nearinfrared(635-1064 nm)performance.Particularly under 1064 nm illumination at zero bias,the device achieves a responsivity of 2.86 A/W and specific detectivity of 1.41×10^(12)Jones.Notably,the external quantum efficiency reaches an exceptional value of 334%compared to the initial 11.5%,while maintaining ultrafast response characteristics with rise/fall times of 11.6/15.6μs.This work provides new insights into interface engineering through molecular doping for developing high-performance vd W optoelectronic devices. 展开更多
关键词 MoTe_(2)/ReS_(2)heterostructure broadband photodetector surface charge transfer doping P-I-N
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GC-IMS联合HS-SPME-GC-MS及化学计量学对3种咖啡果皮茶特征风味物质的表征与鉴别
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作者 孟从燕 李建伟 +5 位作者 吴杰 冯浩春 陈伟祥 李治林 徐娟 侯英 《食品工业科技》 北大核心 2026年第8期347-358,I0035-I0044,共22页
为探究不同初加工咖啡果皮茶中特征风味物质的差异,采用气相-离子迁移谱(gas chromatography-ion mobility spectrometry,GC-IMS)技术和顶空-固相微萃取-气相色谱-质谱(headspace solid phase microextraction-gas chromatography-mass ... 为探究不同初加工咖啡果皮茶中特征风味物质的差异,采用气相-离子迁移谱(gas chromatography-ion mobility spectrometry,GC-IMS)技术和顶空-固相微萃取-气相色谱-质谱(headspace solid phase microextraction-gas chromatography-mass spectrometry,HS-SPME-GC-MS)联用技术测定3种不同初加工咖啡果皮茶的挥发性成分,并进一步结合相对气味活性值(relative odor activity value,ROAV)和化学计量学方法探究不同咖啡果皮茶风味品质的差异性。结果表明:采用GC-IMS法共定性出3种果皮茶104种挥发性有机化合物(volatile organic compounds,VOCs),以醇类、酮类、酯类和醛类等香气物质为主。采用HS-SPME-GC-MS法鉴定出55种VOCs,干法处理样品(CX)中共鉴定出45种VOCs,蜜处理样品(FY)48种,湿法处理样品(GT)48种,以酮类、醛类香气物质为主,醇类、酯类香气物质次之。主成分分析(principal component analysis,PCA)和偏最小二乘回归分析(partial least squares-discriminant analysis,PLS-DA)结果表明,不同初加工三种果皮茶在组成成分和含量上均具有一定的差异。CX样品的风味物质主要与丙酸甲酯、2-丁酮、2,3-二氢-3,5-二羟基-6-甲基-4H-吡喃-4-酮和2,4-二羟基-2,5-二甲基-3(2H)-呋喃-3-酮相关联,FY样品主要与(E)-2-癸烯醛、丙酸丁酯、糠醛和5-乙酰氧基甲基-2-呋喃甲醛物质呈现出较强的相关性,与GT样品相关性较强的风味物质则是乙酸己酯、仲辛酮、香叶基丙酮和月桂酸。通过PLS-DA中的变量重要性投影(variable importance in projection,VIP)和ROAV共筛选出(E)-2-癸烯醛、1-己醇、3-甲基丁醛、乙酸丁酯、庚酸乙酯、2-呋喃甲硫醇、2,4-二羟基-2,5-二甲基-3(2H)-呋喃-3-酮7种关键气味标志物。香气轮廓剖析结果表明不同初加工咖啡果皮茶的香气特征存在差异,GT样品呈现出更浓郁的酸香、辛香、坚果香与烤香;FY样品则呈现出最为突出的花香特征;而CX样品则表现出较为浓郁的坚果香与烤香。本研究为咖啡果皮茶初加工工艺过程中原料筛选和风味品质评价提供参考。 展开更多
关键词 咖啡果皮茶 气相离子迁移谱 顶空固相微萃取-气相色谱-质谱联用 挥发性有机化合物
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