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双层单原子催化剂用于促进高活性和选择性电催化硝酸盐还原制氨

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物理化学学报 2024年第6期40卷 60-62页

作者：于镜坤雍雪曹昂卢思宇郑州大学化学学院绿色催化中心郑州450001 Department of Chemistry University of SheffieldSheffieldS37HFUK Department of Physics Technical University of DenmarkKongens Lyngby 2800Denmar

高效、高选择性的单原子催化剂(SACs)在电催化硝酸盐还原制氨过程中具有重要作用。然而,由于中间体、金属活性中心和配位环境之间复杂的竞争性电子相互作用,仍然面临挑战。本研究采用密度泛函理论(DFT)计算,对27种SACs以及双层SACs(BSA... 详细信息

高效、高选择性的单原子催化剂(SACs)在电催化硝酸盐还原制氨过程中具有重要作用。然而,由于中间体、金属活性中心和配位环境之间复杂的竞争性电子相互作用,仍然面临挑战。本研究采用密度泛函理论(DFT)计算,对27种SACs以及双层SACs(BSACs)进行了系统研究,通过轴向d-d轨道杂化提高了从SACs到BSACs的电催化硝酸盐还原反应(NO_(3)RR)的活性和选择性。考虑到可能的O端、N端、NO端和NO二聚体途径,计算结果显示,在单层SACs中,Ti-Pc和V-Pc分别具有优异的极限电位(U_(L)),分别为-0.24和-0.48V。形成能、溶解势以及从头算分子动力学结果表明,在反应条件下,这些催化剂非常稳定。在这些单层TM-Pc中,它们的d带能级和占据数受到d_(xz)/d^(yz)和p_(z)轨道杂化的影响。其轴向d_(z^(2))轨道的可用性通过形成d_(z^(2))-d_(z^(2))相互作用来进一步调整d带和反应性。在此基础上,以Ti-Pc和V-Pc为底物,通过形成轴向d-d轨道杂化来构建BSACs,为调节NO_(3)RR催化性能提供了一种独特的新途径。重要的是,我们发现d带中心(εd)、d_(xz)+d_(yz)轨道的占据数和U_(L)之间存在二维火山关系,用于描述它们的NO_(3)RR催化性能。最佳的BSACs应该同时具备适当的ε_(d)和d_(xz)+d_(yz)占用数。Ti-Mo和Ti-Ta被确定为出色的NO_(3)RR催化剂,其U_(L)均降低至-0.13 V。而d_(z^(2))-d_(z^(2))轨道之间的杂化则增强了双层金属之间的电荷转移和结构稳定性。缺乏相邻的金属位点将导致生成NO_(2)、NO和N_(2)的能垒较高,从而抑制副产物生成。最终,本研究揭示了在SACs和BSACs上对硝酸盐还原进行合理优化的方法,可为改进电催化剂的设计提供指导。

关键词：硝酸盐还原第一性原理计算单原子催化剂双层单原子催化剂轴向轨道杂化

Anion-induced electrolyte chemistry enables high energy density primary battery for ultralow-temperature conditions

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Science China Chemistry 2024年

作者： zi-Hang Xue Hao-Jie Liang Yong-Li Heng Jia-Lin Yang Edison Huixiang ang Hong-Yan Lü Hong Yu Dong-Mei Dai Dai-Huo Liu Chuan-Yu zheng Wei Guo Xing-Long Wu Department of Chemistry Northeast Normal University MOE Key Laboratory for UV Light-Emitting Materials and Technology Northeast Normal University Natural Sciences and Science Education National Institute of Education Nanyang Technological University State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal Materials Northwestern Polytechnical University School of Chemistry and Chemical Engineering Henan Normal University Key Laboratory of Organo-Pharmaceutical Chemistry of Jiangxi Province Gannan Normal University

Lithium/fluorinated-carbon（Li/CFx） primary batteries are widely used in defense and military fields due to their stable discharge plateau, low self-discharge rate, and adaptability across a wide temperature range. However, enhancing their overall energy density and discharge capacity at low temperatures remains a critical challenge. Herein, we report a strategically designed LiBF4-based sulfite/carboxylate electrolyte, where the anion-involved solvation structure significantly enhances electrochemical kinetics by reducing the desolvation barrier. Simultaneously, it introduces a radical reaction mechanism that contributes to additional capacity. As a result, the Li/CFxprimary batteries with this formulated electrolyte deliver a specific capacity of 2,257.15 mAh g-1at 25 °C. More importantly, when operating at -40 °C, the batteries exhibit an exceptionally high discharge capacity of 1,549.4 m Ah g-1and an energy density of 2,868.6 Wh kg-1. Even at -60 °C, the Li/CFxcells achieve a specific capacity of 444.3 mAh g-1and an energy density of 821.8 Wh kg-1at 0.1 C, significantly outperforming previously reported organic-based liquid electrolytes. This work offers a viable strategy for enhancing the specific capacity and energy density of primary batteries in extreme environments, providing valuable insights for future developments.

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基于宽度自编码网络的单分类集成算法

信号处理 2024年第4期40卷 776-788页

作者：施一帆陈宇昂曾焕强杨楷翔华侨大学工学院福建泉州362021 华南理工大学计算机科学与工程学院广东广州510006 计算机软件新技术国家重点实验室江苏南京210023

异常检测是模式识别领域的经典研究,然而在极端类别不平衡场景下,异常样本匮乏,训练数据仅包含正常样本,传统异常检测方法难以适用。因此,单分类算法逐渐受到关注,它只使用目标类样本构建决策边界,实现对非目标类样本的识别。目前单分... 详细信息

异常检测是模式识别领域的经典研究,然而在极端类别不平衡场景下,异常样本匮乏,训练数据仅包含正常样本,传统异常检测方法难以适用。因此,单分类算法逐渐受到关注,它只使用目标类样本构建决策边界,实现对非目标类样本的识别。目前单分类算法已经取得了显著进展,然而也存在一些局限性:(1)原始特征空间容易受噪声特征干扰;(2)单模型的单分类算法难以从多个特征空间学习更全面的决策边界;(3)缺少对先前模型的欠拟合样本进行针对性学习。为了解决这些问题,本文提出了基于宽度自编码网络的单分类集成算法(Ensemble One-class Classification Based on BLS-Autoencoder,EOC-BLSAE)。首先,本文设计了一种单分类宽度自编码网络模型(One-class BLS-Autoencoder,OC-BLSAE),它能高效学习原始特征空间到重构特征空间的非线性映射关系,利用重构误差构建决策边界;接着,本文设计了单分类Boosting策略,通过最小化全局重构损失,迭代学习欠拟合样本,从而多角度构建OC-BLSAE模型,并自适应评估模型的可靠性;最终,加权集成多个OC-BLSAE模型,有效提升整体算法准确性和鲁棒性。在实验中,本文在16个不同规模的单分类任务上进行参数实验、对比实验和消融实验,结果表明所提算法参数选择较为灵活,算法各模块能够相互协同,有效提升单分类任务的准确性和鲁棒性,整体性能超过前沿单分类方法。

关键词：单分类异常检测宽度学习系统集成学习

基于多位移光谱遥感图像的空间引力模型亚像元定位

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哈尔滨工程大学学报 2024年第6期45卷 1179-1186页

作者：王鹏严昂陈永康赵春雷石立新中国测绘科学研究院测绘科学与地球空间信息技术自然资源部重点实验室北京100039 湖南省国土资源规划院自然资源部南方丘陵区自然资源监测监管重点实验室湖南长沙410114 南京航空航天大学电子信息工程学院江苏南京211106 河北省气象科学研究所河北省气象与生态环境重点实验室河北石家庄050022

目前基于多位移光谱遥感图像的亚像元定位方法通常很少考虑点扩散函数效应影响,本文提出了一种基于多位移光谱遥感图像的空间引力模型亚像元定位方法。为了生成粗糙丰度图像,首先对多个多位移光谱遥感图像进行解混;在点扩散函数效应被... 详细信息

目前基于多位移光谱遥感图像的亚像元定位方法通常很少考虑点扩散函数效应影响,本文提出了一种基于多位移光谱遥感图像的空间引力模型亚像元定位方法。为了生成粗糙丰度图像,首先对多个多位移光谱遥感图像进行解混;在点扩散函数效应被考虑的前提下,对粗糙丰度图像实施面积到点的克里插值处理,然后通过理想方波滤波进行滤波,最终获得改进后的粗糙丰度图像;利用空间引力模型对改进后的粗糙丰度图像进行上采样,从而得到上采样丰度图像,再对上采样丰度图像执行整合处理,以生成精细丰度图像;在完成上述所有图像处理步骤后,最终通过应用类别分配方法,将类别标签分发给各个亚像元,以此获得精确的定位结果。在2组实验数据集上的实验结果表明:本文提出的方法比现有的亚像元定位方法获得了更好的定位效果。

关键词：遥感图像高光谱图像亚像元定位点扩散函数空间引力模型多位移光谱遥感图像

Refining constitutive relation by integration of finite element simulations and Gleeble experiments

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Journal of Materials Science & Technology 2019年第6期35卷 1039-1043页

作者： D.J. Yu D.S. Xu H. W ang z.B. zhao G.z. Wei R. Yang College of Sciences Northeastern University Shenyang 110004 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Thermo-mechanical coupled finite element calculations were carried out to simulate the Gleeble compression of the samples of a titanium alloy(Ti60), and the results are analyzed and compared with the actual compression tests conducted on a Gleeble 3800 thermo-mechanical simulator. The changes in temperature, stress and strain distribution in the samples and the source of error on the constitutive relations from Gleeble hot compression test were analyzed in detail. Both simulations and experiments showed that the temperature distribution in the specimen is not uniform during hot compression, resulting in significant deformation inhomogeneity and non-ignorable error in the flow stress strain relation,invalidating the uniform strain assumption commonly assumed when extracting the constitutive relation from Gleeble tests. Based on the finite element simulations with iterative corrections, we propose a scheme to refine the constitutive relations from Gleeble tests.

关键词： Titanium alloy Constitutive relation Finite element Compression Temperature distribution

Gradient Structured Copper by Rotationally Accelerated Shot Peening

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Journal of Materials Science & Technology 2017年第7期33卷 758-761页

作者： X.Wang Y.S.Li Q.z.ang Y.H.zhao Y.T.zhu Nano Structural Materials Center School of Materials Science and Engineering Nanjing University of Science and Technology Nanjing 210094 China School of Mechanical Engineering Nanjing University of Science and Technology Nanjing 210094 China Department of Materials Science and Engineering North Carolina State University Raleigh NC 27695 USA

A new technology-rotationally accelerated shot peening（RASP）, was developed to prepare gradient structured materials. By using centrifugal acceleration principle and large steel balls, the RASP technology can produce much higher impact energy compared to conventional shot peening. As a proof-of-concept demonstration, the RASP was utilized to refine the surface layer in pure copper（Cu） with an average grain size of 85 nm. The grain size increases largely from surface downwards the bulk, forming an800 ？m thick gradient-structured surface layer and consequently a micro-hardness gradient. The difference between the RASP technology and other established techniques in preparing gradient structured materials is discussed. The RASP technology exhibits a promoting future for large-scale manufacturing of gradient materials.

关键词： Microstructure Rotationally accelerated shot peening Gradient structure Hardness Copper

STCF conceptual design report (Volume 1): Physics & detector

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Frontiers of physics 2024年第1期19卷 1-154页

作者： M.Achasov X.C.Ai L.P.An R.Aliberti Q.An X.z.Bai Y.Bai O.Bakina A.Barnyakov V.Blinov V.Bobrovnikov D.Bodrov A.Bogomyagkov A.Bondar I.Boyko z.H.Bu F.M.Cai H.Cai J.J.Cao Q.H.Cao X.Cao z.Cao Q.Chang K.T.Chao D.Y.Chen H.Chen H.X.Chen J.F.Chen K.Chen L.L.Chen P.Chen S.L.Chen S.M.Chen S.Chen S.P.Chen W.Chen X.Chen X.F.Chen X.R.Chen Y.Chen Y.Q.Chen H.Y.Cheng J.Cheng S.Cheng T.G.Cheng J.P.Dai L.Y.Dai X.C.Dai D.Dedovich A.Denig I.Denisenko J.M.Dias D.z.Ding L.Y.Dong W.H.Dong V.Druzhinin D.S.Du Y.J.Du z.G.Du L.M.Duan D.Epifanov Y.L.Fan S.S.Fang z.J.Fang G.Fedotovich C.Q.Feng X.Feng Y.T.Feng J.L.Fu J.Gao Y.N.Gao P.S.Ge C.Q.Geng L.S.Geng A.Gilman L.Gong T.Gong B.Gou W.Gradl J.L.Gu A.Guevara L.C.Gui A.Q.Guo F.K.Guo J.C.Guo J.Guo Y.P.Guo z.H.Guo A.Guskov K.L.Han L.Han M.Han X.Q.Hao J.B.He S.Q.He X.G.He Y.L.He z.B.He z.X.Heng B.L.Hou T.J.Hou Y.R.Hou C.Y.Hu H.M.Hu K.Hu R.J.Hu W.H.Hu X.H.Hu Y.C.Hu J.Hua G.S.Huang J.S.Huang M.Huang Q.Y.Huang W.Q.Huang X.T.Huang X.J.Huang Y.B.Huang Y.S.Huang N.Hüsken V.Ivanov Q.P.Ji J.J.Jia S.Jia z.K.Jia H.B.Jiang J.Jiang S.z.Jiang J.B.Jiao z.Jiao H.J.Jing X.L.Kang X.S.Kang B.C.Ke M.Kenzie A.Khoukaz I.Koop E.Kravchenko A.Kuzmin Y.Lei E.Levichev C.H.Li C.Li D.Y.Li F.Li G.Li G.Li H.B.Li H.Li H.N.Li H.J.Li H.L.Li J.M.Li J.Li L.Li L.Li L.Y.Li N.Li P.R.Li R.H.Li S.Li T.Li W.J.Li X.Li X.H.Li X.Q.Li X.H.Li Y.Li Y.Y.Li z.J.Li H.Liang J.H.Liang Y.T.Liang G.R.Liao L.z.Liao Y.Liao C.X.Lin D.X.Lin X.S.Lin B.J.Liu C.W.Liu D.Liu F.Liu G.M.Liu H.B.Liu J.Liu J.J.Liu J.B.Liu K.Liu K.Y.Liu K.Liu L.Liu Q.Liu S.B.Liu T.Liu X.Liu Y.W.Liu Y.Liu Y.L.Liu z.Q.Liu z.Y.Liu z.W.Liu I.Logashenko Y.Long C.G.Lu J.X.Lu N.Lu Q.F.Lü Y.Lu Y.Lu z.Lu P.Lukin F.J.Luo T.Luo X.F.Luo Y.H.Luo H.J.Lyu X.R.Lyu J.P.Ma P.Ma Y.Ma Y.M.Ma F.Maas S.Malde D.Matvienko z.X.Meng R.Mitchell A.Nefediev Y.Nefedov S.L.Olsen Q.Ouyang P.Pakhlov G.Pakhlova X.Pan Y.Pan E.Passemar Y.P.Pei H.P.Peng L.Peng X.Y.Peng X.J.Peng K.Peters S.Pivovarov E.Pyata B.B.Qi Y.Q.Qi W.B.Qian Y.Qian C.F.Qiao J.J.Qin J.J.Qin L.Q.Qin X.S.Qin T.L.Qiu J.Rademacker C.F.Redmer H.Y.Sang Anhui University Hefei 230039China Beihang University Beijing 100191China Budker Institute of Nuclear Physics Novosibirsk 630090Russia CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China Cavendish Laboratory University of CambridgeJJ Thomson AveCambridge CB30HEUnited Kingdom Central China Normal University Wuhan 430079China Central South University Changsha 410083China China University of Geosciences Wuhan 430074China China University of Mining and Technology Xuzhou 221116China École Polytechnique Fédérale de Lausanne(EPFL) LausanneSwitzerland Fudan University Shanghai 200433China Goethe University Frankfurt D-60325 Frankfurt am MainGermany Guangxi Normal University Guilin 541004China Guangxi Uninversity Nanning 530004China Hangzhou Institute for Advanced Study UCASHangzhou 310024China Hebei Normal University Shijiazhuang 050024China Hebei University Baoding 071002China Hefei University of Technology Hefei 230601China Helmholtz Institute Mainz Staudinger Weg 18D-55099 MainzGermany Henan Normal University Xinxiang 453007China Henan University Kaifeng 475004China High Energy Physics Center Chung-Ang UniversitySeoul 06974Korea Higher School of Economy 11 Pokrovsky Bulvar Moscow 109028Russia Huangshan University Huangshan 245000China Hubei University of Automotive Technology Shiyan 442002China Hunan Normal University Changsha 410081China Hunan University of Science and Technology Xiangtan 411201China Hunan University Changsha 410082China Indiana University BloomingtonIndiana 47405USA Inner Mongolia University Hohhot 010021China Institute of Advanced Science Facilities Shenzhen 518107China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Institute of Physics Academia SinicaTaipeiTaiwan 11529China Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100190China Jilin University Changch

The superτ-charm facility(STCF)is an electron–positron collider proposed by the Chinese particle physics *** is designed to operate in a center-of-mass energy range from 2 to 7 GeV with a peak luminosity of 0.5×10^(35) cm^(–2)·s^(–1) or *** STCF will produce a data sample about a factor of 100 larger than that of the presentτ-charm factory—the BEPCII,providing a unique platform for exploring the asymmetry of matter-antimatter(charge-parity violation),in-depth studies of the internal structure of hadrons and the nature of non-perturbative strong interactions,as well as searching for exotic hadrons and physics beyond the Standard *** STCF project in China is under development with an extensive R&D *** document presents the physics opportunities at the STCF,describes conceptual designs of the STCF detector system,and discusses future plans for detector R&D and physics case studies.

关键词： electron–positron collider tau-charm region high luminosity STCF detector conceptual design

能谱CT碘基值预测局部进展期胃腺癌新辅助化疗疗效

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放射学实践 2024年第1期39卷 77-82页

作者：马千昂黎海亮王艺蒋志强徐淑宁李靖郑州大学附属肿瘤医院(河南省肿瘤医院)医学影像科郑州450008 郑州大学附属肿瘤医院(河南省肿瘤医院)病理科郑州450008 郑州大学附属肿瘤医院(河南省肿瘤医院)普外科郑州450008 郑州大学附属肿瘤医院(河南省肿瘤医院)消化肿瘤内科郑州450008

目的:探讨基线期能谱CT碘基值预测局部进展期胃腺癌新辅助化疗(NAC)后病理学反应的应用价值。方法:2021年1月至2021年12月间,前瞻性对拟行新辅助化疗联合手术治疗的局部进展期胃腺癌患者于治疗前1周内行能谱CT动脉期、静脉期和延迟期三... 详细信息

目的:探讨基线期能谱CT碘基值预测局部进展期胃腺癌新辅助化疗(NAC)后病理学反应的应用价值。方法:2021年1月至2021年12月间,前瞻性对拟行新辅助化疗联合手术治疗的局部进展期胃腺癌患者于治疗前1周内行能谱CT动脉期、静脉期和延迟期三期增强扫描。收集患者临床病理信息,测量增强各期胃癌病灶的碘基值(IC),并除以主动脉碘基值得到标化碘基值(nIC)。根据术后AJCC肿瘤退缩分级(TRG)标准分为病理缓解良好组(TRG=0+1)和病理缓解不良组(TRG=2+3)。比较两组间临床指标和碘基值的差异,采用多因素回归方法筛选胃癌NAC疗效的独立预测因素,采用受试者工作特征曲线和曲线下面积(AUC)评估IC值的预测效能。结果:筛选出符合条件的患者70例,其中男55例,女15例,年龄范围30~71岁,中位年龄59岁。病理缓解良好22例,缓解不良48例。缓解良好组的静脉期标化碘基值(nICVP)、延迟期标化碘基值(nICDP)值低于缓解不良组,差异有统计学意义(t=2.391、2.270,P均z=2.306、2.161、2.228,P均0.684为诊断阈值,其预测病理缓解不良的敏感度、特异度、阳性预测值、阴性预测值分别为75.00%、81.80%、65.58%、87.71%。结论:基线期胃癌病灶nICVP和nICDP能鉴别新辅助化疗后不同病理缓解状态,nICVP和CT报告淋巴结状态是预测新辅助化疗疗效的独立风险因素,联合两者能进一步提高预测效能。

关键词：能谱CT 体层摄影术 X线计算机碘基值胃肿瘤疗效预测新辅助化疗

Precise asymptotics in the law of the logarithm for random fields in Hilbert space

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Journal of zhejiang University-Science A(Applied Physics & Engineering) 2007年第4期8卷 651-659页

作者： FU Ke-ang z.ang Li-xin Department of Mathematics Zhejiang University Hangzhou 310027 China

Consider the positive d-dimensional lattice z^d（d≥2） with partial ordering ≤, let {XK; K∈z＋^d} be i.i.d, random variables taking values in a real separable Hilbert space （H, ｜｜·｜｜） with mean zero and covariance operator ∑ and set partial sums SN =∑K≤nXK,K,N∈z＋^d. Under some moment conditions, we obtain the precise asymptotics of a kind of weighted infinite series for partial sums SN as ε↓ by using the truncation and approximation methods. The results are related to the convergence rates of the law of the logarithm in Hilbert space, and they also extend the results of （Gut and Spataru, 2003）.

关键词： The law of the logarithm Random field Hilbert space. Tail probabilitv. Truncation method