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密度泛函理论软件ABACUS进展及其与深度学习算法的融合及应用

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金属学报 2024年第10期60卷 1405-1417页

作者：陈默涵北京大学工学院应用物理与技术研究中心、高能量密度物理数值模拟教育部重点实验室北京100871 北京科学智能研究院北京100080

基于量子力学基本原理的密度泛函理论(DFT)可以有效预测材料性质,如今它在物理、化学、材料、生物等领域的研究工作中已得到广泛应用。随着对材料领域的深入研究,进一步提升DFT的精度和效率已成为迫切需求,但精度和效率往往不可兼得。... 详细信息

基于量子力学基本原理的密度泛函理论(DFT)可以有效预测材料性质,如今它在物理、化学、材料、生物等领域的研究工作中已得到广泛应用。随着对材料领域的深入研究,进一步提升DFT的精度和效率已成为迫切需求,但精度和效率往往不可兼得。近年来,在AI for Science理念的引领下,基于深度学习的电子结构计算方法迅速发展,有望解决电子结构计算中精度和效率不能两全的困境。然而,只有稳定可靠的DFT软件平台才能保证深入研究和持续推动AI辅助电子结构计算方法的广泛应用,这既充满挑战又蕴含机遇。在此背景下,本文主要从物理模型、深度学习算法和软件开发3方面介绍国产开源DFT软件ABACUS(atomic-orbital based ab-initio computation at UStc,中文名原子算筹)从开发2.2版本(2022年4月发布)到发布3.7版本(2024年7月发布)期间的进展及其与深度学习算法的融合和应用。

关键词： ABACUS 密度泛函理论开源软件深度学习计算材料科学

Signature of the hydrogen-bonded environment of liquid water in X-ray emission spectra from first-principles calculations

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Frontiers of physics 2018年第1期13卷 15-24页

作者： Huaze Shen mohan chen Zhaoru Sun Limei Xu Enge Wang Xifan Wu International Centre for Quantum Materials and School of Physics Peking University Beijing 100871 China Department of Physics Temple University Philadelphia PA 19122 USA Institute for Computational Molecular Science Temple University Philadelphia PA 19122 USA

Based on ab initio molecular dynamics simulations and density functional theory, we performed a systematic theoretical study to elucidate the correlation between the H-bonded environment and X- ray emission spectra of liquid water. The spectra generated from excited water molecules embedded in an intact H-bonded environment yield broader spectral peaks and a larger spectral range than the spectra generated from water molecules in a broken H-bonded environment. Such differences are caused by the local electronic structures on the excited water molecules within the core-hole lifetime that evolve differently through the rearrangement of neighboring water molecules in different H-bonded environments.

关键词： water density functional theory ab initio molecular dynamics X-ray emission spectra,hydrogen bond core hole

Thermal transport by electrons and ions in warm dense aluminum:A combined density functional theory and deep potential study

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Matter and Radiation at Extremes 2021年第2期6卷 17-27页

作者： Qianrui Liu Junyi Li mohan chen CAPT HEDPSCollege of EngineeringPeking UniversityBeijing 100871People’s Republic of China School of Computer Science and Technology Harbin Institute of Technology(Shenzhen)ShenzhenGuangdong 518055People’s Republic of China

We propose an efficient scheme that combines density functional theory(DFT)with deep potentials(DPs),to systematically study convergence issues in the computation of the electronic thermal conductivity of warm dense aluminum(2.7 g/cm^(3)and temperatures ranging from 0.5 eV to 5.0 eV)with respect to the number of k-points,the number of atoms,the broadening parameter,the exchange-correlation functionals,and the ***,we obtain the ionic thermal conductivity using the Green–Kubo method in conjunction with DP molecular dynamics simulations,and we study size effects on the ionic thermal *** work demonstrates that the proposed method is efficient in evaluating both electronic and ionic thermal conductivities of materials.

关键词： materials. functional theory

A Letter to Chinese Women’s Volleyball Team

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疯狂英语（初中天地） 2024年第10期 73-73页

作者：陈沫含闫明(指导) 黑龙江省大庆市林甸县第二中学不详

Dear Chinese Women’s Volleyball Team,When I see you striving on the court,I feel very *** are my super heroes and I’m proud of *** history of the Chinese Women’s Volleyball Team is full of many excellent *** have w... 详细信息

关键词： Volley court excited

Variable Learning-Memory Behavior fromπ-Conjugated Ligand to Ligand-Containing Cobalt(II)Complex

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Chinese Journal of Chemistry 2022年第19期40卷 2296-2304页

作者： cheng Zhang mohan chen Guan Wang Ming Teng Songtao Ling Yanan Wang Zhaojun Su Kun Gao Xinbo Yang Chunlan Ma Yang Li Qichun Zhang Jiangsu Key Laboratory of Micro and Nano Heat Fluid Flow Technology and Energy Application School of Physical Science and TechnologySuzhou University of Science and TechnologySuzhouJiangsu 215009China College of Chemistry Chemical Engineering and Materials ScienceSoochow UniversitySuzhouJiangsu 215123China School of Petrochemical Engineering Changzhou UniversityChangzhouJiangsu 213164China College of Energy Soochow Institute for Energy and Materials InnovationS(SiEMIS)Soochow UniversitySuzhouJiangsu 215006China Department of Materials Science and Engineering City University of Hong KongKowloonHong KongChina Center of Super-Diamond and Advanced Films(COSDAF) City University of HongkongHong Kong SAR999077 China

In the information-explosion era,developing novel algorithms and memristive devices has become a promising concept for next-generation capacity enlargement *** small molecule-based devices displaying superior learning-memory performance have attracted much attention,except for the existence of poor heat-resilience and mediocre *** this paper,a strategy of transforming an organic-type data-storage material to metal complex is proposed to resolve these intrinsic issues.A pristine NDI-derivative(NIPy)and its corresponding Co(II)complex(CoNIPy)are synthesized for the purpose of electrical property *** complex-based memristive device exhibits superior ternary WORM memory performance compared with the binary behavior of NIPy,including>104 s of reading,lower threshold voltage(V_(th)),1:10^(2):10^(5)of OFF/ON1/ON2 current ratio,and long-term stability in heating *** variable learning-memory behavior can be attributed to the enhanced ligand-to-metal charge transfer(LMCT)and improved redox activity after the introduction of central metal atom and coordination *** studies on material innovation and optimal performance are of great importance not only for environmentally-robust memristive devices but also for practical application of a host of organic electronic devices.

关键词： Charge transfer Coordination modes Nitrogen heterocycles Naphthalimide(NDI) Memory devices

Effect of continuous positive airway pressure ventilation on nocturnal ST-segment changes in patients with sleep-disordered breathing

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Journal of Geriatric Cardiology 2007年第2期4卷 101-104页

作者： Wenli Zhang Shiwen Wang Rui chen mohan Liu Lin Wang Lei Gao Caiyi Lu Institute of Geriatric Cardiology Chinese PLA General Hospital Beijing 100853 China Institute of Geriatric Cardiology Chinese PLA General Hospital Beijing 100853 China Institute of Geriatric Cardiology Chinese PLA General Hospital Beijing 100853 China Institute of Geriatric Cardiology Chinese PLA General Hospital Beijing 100853 China Institute of Geriatric Cardiology Chinese PLA General Hospital Beijing 100853 China Institute of Geriatric Cardiology Chinese PLA General Hospital Beijing 100853 China Institute of Geriatric Cardiology Chinese PLA General Hospital Beijing 100853 China

Objective To determine whether sleep-disordered breathing (SDB) may lead to nocturnal myocardial ischemia and whether the severity of this ischemia may be relieved by nasal continuous positive airway pressure (CPAP). Methods Overnight polysomnogram examination and simultaneous 3-channel Holter monitoring were performed on 76 patients with moderate to severe SDB and no history of coronary heart disease. All the cases were treated with CPAP for one night. ST depression was defined as a ST segment decrease of more than 1 mm from baseline and lasting 1 min or more. The total duration (minutes) of ST depression was indexed to the total sleep time (minutes per hour of sleep). Results Twenty-eight patients (37%) showed ST segment depression during their sleep. Before CPAP treatment, the respiratory disturbance index (RDI) and arousal index were significantly higher during periods of ST depression than when ST segments were isoelectric, whereas no significant difference was found in blood oxygen saturation (SaO2). After the CPAP treatment of patients with ST depression, the duration of ST depression was significantly reduced from 36.8±18.9 to 11.4±13.2 min/h (P<0.05). ST depression-related indexes, including RDI, arousal index and the percentage of sleep time spent at SaO2 below 90% (TS90/ TST), were all significantly decreased, with RDI from 63.4±23.8 to 8.1±6.6 /h, arousal index from 51.2±18.9 to 9.6±5.4 /h, and TS90/ TST from 50.6±21.4 to 12.9±14.7% (P<0.05). Conclusion ST-segment depression is rather common in patients with moderate to severe SDB, and CPAP treatment can significantly reduce the duration of ST depression. ST depression in these patients may reflect the myocardial ischemia that really exists and the non-ischemic changes associated with recurrent SDB.

关键词： ST-segment depression myocardial ischemia sleep-disordered breathing continuous positive airway pressure

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复杂信号环境下的GNSS定位星座选择算法

哈尔滨工程大学学报 2011年第1期32卷 85-89页

作者：陈陌寒郑睿王云陈杰中国科学院微电子研究所通信与多媒体SOC研究室北京100029

为了有效减小全球导航卫星系统(GNSS)接收机在复杂信号环境下的定位误差,提出一种定位星座选择算法.该算法利用简化的距离残差平方和作为检验统计量,该检验统计量可以反映单颗卫星的伪距测量误差进而实时反映定位误差的变化.基于该检验... 详细信息

为了有效减小全球导航卫星系统(GNSS)接收机在复杂信号环境下的定位误差,提出一种定位星座选择算法.该算法利用简化的距离残差平方和作为检验统计量,该检验统计量可以反映单颗卫星的伪距测量误差进而实时反映定位误差的变化.基于该检验统计量,提出的定位星座选择算法能够检测出多个错误观测量进而将其去除.测试表明,这种定位星座选择算法可以大幅度减小定位点的错误概率,性能优于传统GDOP(几何精度因子)定位星座选择算法;长时间连续定点定位仿真测试中平均有效性超过80%,动态测试中有效性超过70%.

关键词：全球导航卫星系统复杂信号环境星座选择伪距测量误差载噪比

二元醇共价交联羧基化石墨烯复合膜和正丁醇脱水性能

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化工进展 2022年第7期41卷 3801-3807页

作者：韩光鲁路宽吕杰张永辉陈墨涵郑州轻工业大学材料与化学工程学院河南郑州450001 河南省化工分离过程强化工程技术研究中心河南郑州450001

以二元醇(乙二醇、1,3-丙二醇和1,4-丁二醇)为交联剂,通过抽滤的方式在涂覆盐酸多巴胺的聚醚砜(PES)支撑层上制备了共价交联的羧基化石墨烯/聚醚砜(CG/PES)复合膜。稳定性测试证明盐酸多巴胺的涂覆和二元醇的交联显著提高了分离层和支... 详细信息

以二元醇(乙二醇、1,3-丙二醇和1,4-丁二醇)为交联剂,通过抽滤的方式在涂覆盐酸多巴胺的聚醚砜(PES)支撑层上制备了共价交联的羧基化石墨烯/聚醚砜(CG/PES)复合膜。稳定性测试证明盐酸多巴胺的涂覆和二元醇的交联显著提高了分离层和支撑层以及CG纳米片间的结合力。采用扫描电子显微镜、X射线衍射仪、X射线光电子能谱仪和水接触角测试仪对复合膜的物化性质和微观形貌进行了表征。结果表明,所得复合膜的分离层连续无缺陷,厚度在60~64nm之间。二元醇与CG纳米片上的羧基成功发生反应,将CG纳米片锚固在一起。交联剂的引入没有大幅降低亲水性且实现了对分离层层间距的有效调控,随二元醇分子尺寸增加,所得复合膜的层间距由0.761nm提高到0.778nm。CG/PES复合膜对正丁醇/水混合物具有优良的渗透汽化分离性能。在料液温度为50℃、料液中水的质量分数为10%时,三种交联剂所得复合膜的渗透通量分别达到0.79kg/(m^(2)·h)、0.87kg/(m^(2)·h)和0.96kg/(m^(2)·h),而分离因子比未交联的复合膜高一个数量级。15天的稳定性测试结果表明,所得复合膜分离性能无显著变化,能够满足渗透汽化应用要求。

关键词：膜分离渗透汽化羧基化石墨烯交联正丁醇脱水

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超音速火焰喷涂结晶器铜板Ni60A涂层真空退火研究

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热加工工艺 2015年第6期44卷 132-135页

作者：陈忠张世宏陈默含林玥安徽工业大学材料科学与工程学院安徽马鞍山243002

采用超音速火焰喷涂技术在结晶器铜板表面制备了高硬度、高耐磨性的Ni60A涂层,研究了真空退火对喷涂层显微组织、显微硬度及高温磨损性能的影响。采用金相显微镜、场发射扫描电镜和X衍射仪分析了喷涂层的显微组织、磨痕形貌和相结构,利... 详细信息

采用超音速火焰喷涂技术在结晶器铜板表面制备了高硬度、高耐磨性的Ni60A涂层,研究了真空退火对喷涂层显微组织、显微硬度及高温磨损性能的影响。采用金相显微镜、场发射扫描电镜和X衍射仪分析了喷涂层的显微组织、磨痕形貌和相结构,利用显微硬度计和销盘高温磨损仪检测了喷涂层的硬度和高温耐磨性。结果表明:喷涂层主相为固溶体相γ-(Ni,Fe),此外还有Cr23C6和NixSi相;真空退火后喷涂层显微硬度减小,但涂层组织变得更加致密,涂层500℃高温摩擦系数明显降低,磨损机理均为较轻的黏着磨损。

关键词：超音速火焰喷涂结晶器 Ni60A涂层真空退火组织和性能