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Development, applications and challenges of ReaxFF reactive force field in molecular simulations

You Han, Dandan Jiang, Jinli Zhang, Wei Li, Zhongxue Gan, Junjie Gu

《化学科学与工程前沿(英文)》 2016年 第10卷 第1期   页码 16-38 doi: 10.1007/s11705-015-1545-z

摘要: As an advanced and new technology in molecular simulation fields, ReaxFF reactive force field has been developed and widely applied during the last two decades. ReaxFF bridges the gap between quantum chemistry (QC) and non-reactive empirical force field based molecular simulation methods, and aims to provide a transferable potential which can describe many chemical reactions with bond formation and breaking. This review presents an overview of the development and applications of ReaxFF reactive force field in the fields of reaction processes, biology and materials, including (1) the mechanism studies of organic reactions under extreme conditions (like high temperatures and pressures) related with high-energy materials, hydrocarbons and coals, (2) the structural properties of nanomaterials such as graphene oxides, carbon nanotubes, silicon nanowires and metal nanoparticles, (3) interfacial interactions of solid-solid, solid-liquid and biological/inorganic surfaces, (4) the catalytic mechanisms of many types of metals and metal oxides, and (5) electrochemical mechanisms of fuel cells and lithium batteries. The limitations and challenges of ReaxFF reactive force field are also mentioned in this review, which will shed light on its future applications to a wider range of chemical environments.

关键词: ReaxFF     reaction mechanism     nanomaterials     interfacial interaction     catalyst     fuel cell    

formation mechanisms in the cathode-electrolyte interface layer of lithium manganese oxide batteries from reactiveforce field (ReaxFF) based molecular dynamics

Sahithya REDDIVARI, Christian LASTOSKIE, Ruofei WU, Junliang ZHANG

《能源前沿(英文)》 2017年 第11卷 第3期   页码 365-373 doi: 10.1007/s11708-017-0500-8

摘要: Lithium manganese oxide (LiMn O ) is a principal cathode material for high power and high energy density electrochemical storage on account of its low cost, non-toxicity, and ease of preparation relative to other cathode materials. However, there are well-documented problems with capacity fade of lithium ion batteries containing LiMn O . Experimental observations indicate that the manganese content of the electrolyte increases as an electrochemical cell containing LiMn O ages, suggesting that active material loss by dissolution of divalent manganese from the LiMn O surface is the primary reason for reduced cell life in LiMn O batteries. To improve the retention of manganese in the active material, it is key to understand the reactions that occur at the cathode surface. Although a thin layer of electrolyte decomposition products is known to form at the cathode surface, the speciation and reaction mechanisms of Mn in this interface layer are not yet well understood. To bridge this knowledge gap, reactive force field (ReaxFF) based molecular dynamics was applied to investigate the reactions occurring at the LiMn O cathode surface and the mechanisms that lead to manganese dissolution. The ReaxFFMD simulations reveal that the cathode-electrolyte interface layer is composed of oxidation products of electrolyte solvent molecules including aldehydes, esters, alcohols, polycarbonates, and organic radicals. The oxidation reaction pathways for the electrolyte solvent molecules involve the formation of surface hydroxyl species that react with exposed manganese atoms on the cathode surface. The presence of hydrogen fluoride (HF) induces formation of inorganic metal fluorides and surface hydroxyl species. Reaction products predicted by ReaxFF-based MD are in agreement with experimentally identified cathode-electrolyte interface compounds. An overall cathode-electrolyte interface reaction scheme is proposed based on the molecular simulation results.

关键词: lithium manganese oxide batteries     reactive force field (ReaxFF)     cathode-electrolyte interface layer     molecular dynamics    

styrene-butadiene-styrene copolymer on the aging resistance of asphalt: An atomistic understanding from reactive

《结构与土木工程前沿(英文)》 2021年 第15卷 第5期   页码 1261-1276 doi: 10.1007/s11709-021-0761-5

摘要: To reveal the potential influence of styrene-butadiene-styrene (SBS) polymer modification on the anti-aging performance of asphalt, and its mechanism, we explored the aging characteristics of base asphalt and SBS-modified asphalt by reaction force field (ReaxFF) and classical molecular dynamics simulations. The results illustrate that the SBS asphalt is more susceptible to oxidative aging than the base asphalt under oxygen-deficient conditions due to the presence of unsaturated C=C bonds in the SBS polymer. In the case of sufficient oxygen, the SBS polymer inhibits the oxidation of asphalt by restraining the diffusion of asphalt molecules. Compared with the base asphalt, the SBS asphalt exhibits a higher degree of oxidation at the early stage of pavement service and a lower degree of oxidation in the long run. In addition, SBS polymer degrades into small blocks during aging, thus counteracting the hardening of aged asphalt and partially restoring its low-temperature cracking resistance.

关键词: SBS asphalt     oxidative aging     asphalt hardening     ReaxFF     molecular dynamics    

Validation of polarizable force field parameters for nucleic acids by inter-molecular interactions

Liaoran Cao,Hong Ren,Jing Miao,Wei Guo,Yan Li,Guohui Li

《化学科学与工程前沿(英文)》 2016年 第10卷 第2期   页码 203-212 doi: 10.1007/s11705-016-1572-4

摘要: Modeling structural and thermodynamic properties of nucleic acids has long been a challenge in the development of force fields. Polarizable force fields are a new generation of potential functions to take charge redistribution and induced dipole into account, and have been proved to be reliable to model small molecules, polypeptides and proteins, but their use on nucleic acids is still rather limited. In this article, the interactions between nucleic acids and a small molecule or ion were modeled by AMOEBAbio09, a modern polarizable force field, and conventional non-polarizable AMBER99sb and CHARMM36 force fields. The resulting intermolecular interaction energies were compared with those calculated by ab initio quantum mechanics methods. Although the test is not sufficient to prove the reliability of the polarizable force field, the results at least validate its capability in modeling energetics of static configurations, which is one basic component in force field parameterization.

关键词: nucleic acid     polarizable force field     AMOEBA    

Atomistic understanding of interfacial processing mechanism of silicon in water environment: A ReaxFF

《机械工程前沿(英文)》 2021年 第16卷 第3期   页码 570-579 doi: 10.1007/s11465-021-0642-6

摘要: The interfacial wear between silicon and amorphous silica in water environment is critical in numerous applications. However, the understanding regarding the micro dynamic process is still unclear due to the limitations of apparatus. Herein, reactive force field simulations are utilized to study the interfacial process between silicon and amorphous silica in water environment, exploring the removal and damage mechanism caused by pressure, velocity, and humidity. Moreover, the reasons for high removal rate under high pressure and high velocity are elucidated from an atomic perspective. Simulation results show that the substrate is highly passivated under high humidity, and the passivation layer could alleviate the contact between the abrasive and the substrate, thus reducing the damage and wear. In addition to more Si-O-Si bridge bonds formed between the abrasive and the substrate, new removal pathways such as multibridge bonds and chain removal appear under high pressure, which cause higher removal rate and severer damage. At a higher velocity, the abrasive can induce extended tribochemical reactions and form more interfacial Si-O-Si bridge bonds, hence increasing removal rate. These results reveal the internal cause of the discrepancy in damage and removal rate under different conditions from an atomic level.

关键词: silicon     ReaxFF     molecular dynamics     friction     damage    

论零点振动能与Casimir力

黄志洵

《中国工程科学》 2008年 第10卷 第5期   页码 63-69

摘要:

在真空中放置一对平行的金属板(间距很小),两板会由于一个微弱(可测出)的力而有相互靠近的趋势。这种Casimir效应可用量子理论中的零点能(ZPE)解释。科学家们都认为Casimir力存在,但对其产生的原因却有不同看法。空虚空间是否具有能量,其答案或许将决定宇宙的命运。在自然界和人类实验室中,有许多异常现象可用Casimir效应及挠场理论作出说明。

关键词: 零点能     零点场     真空能     Casimir力     挠场理论    

基于变形力监测数据的残余应力场推断和表征方法

赵智伟, 刘长青, 李迎光, James Gao

《工程(英文)》 2023年 第22卷 第3期   页码 49-59 doi: 10.1016/j.eng.2022.07.018

摘要:

残余应力是材料的基本属性之一,与零件的几何/尺寸稳定性和疲劳寿命直接相关。针对具有高精度要求的大型零件,其残余应力场的准确测量和预测一直是一个挑战。目前的残余应力场测量技术分为基于应变的有损法以及效率和精度较低的无损法。本文提出了一种基于变形力推断残余应力场的无损法。本方法通过能够反映去除材料后不平衡残余应力场整体效应的变形力来推断零件的残余应力场。利用虚功原理建立了变形力与残余应力场之间的力学关系,并引入正则化方法求解残余应力场。为验证方法的有效性,本文进行了理论验证和实际实验验证。实验结果表明,该方法对于大型结构件的残余应力场测量具有可靠的精度和灵活性。在数字化和智能制造的趋势下,该方法的基本原理为利用加工监测数据预测和补偿由残余应力引起的零件加工变形提供了重要参考。

关键词: 残余应力场     精密加工     变形力     反问题     在位测量    

Review: Tip-based vibrational spectroscopy for nanoscale analysis of emerging energy materials

Amun JARZEMBSKI, Cedric SHASKEY, Keunhan PARK

《能源前沿(英文)》 2018年 第12卷 第1期   页码 43-71 doi: 10.1007/s11708-018-0524-8

摘要: Vibrational spectroscopy is one of the key instrumentations that provide non-invasive investigation of structural and chemical composition for both organic and inorganic materials. However, diffraction of light fundamentally limits the spatial resolution of far-field vibrational spectroscopy to roughly half the wavelength. In this article, we thoroughly review the integration of atomic force microscopy (AFM) with vibrational spectroscopy to enable the nanoscale characterization of emerging energy materials, which has not been possible with far-field optical techniques. The discussed methods utilize the AFM tip as a nanoscopic tool to extract spatially resolved electronic or molecular vibrational resonance spectra of a sample illuminated by a visible or infrared (IR) light source. The absorption of light by electrons or individual functional groups within molecules leads to changes in the sample’s thermal response, optical scattering, and atomic force interactions, all of which can be readily probed by an AFM tip. For example, photothermal induced resonance (PTIR) spectroscopy methods measure a sample’s local thermal expansion or temperature rise. Therefore, they use the AFM tip as a thermal detector to directly relate absorbed IR light to the thermal response of a sample. Optical scattering methods based on scanning near-field optical microscopy (SNOM) correlate the spectrum of scattered near-field light with molecular vibrational modes. More recently, photo-induced force microscopy (PiFM) has been developed to measure the change of the optical force gradient due to the light absorption by molecular vibrational resonances using AFM’s superb sensitivity in detecting tip-sample force interactions. Such recent efforts successfully breech the diffraction limit of light to provide nanoscale spatial resolution of vibrational spectroscopy, which will become a critical technique for characterizing novel energy materials.

关键词: vibrational spectroscopy     atomic force microscopy     photo-thermal induced resonance     scanning near-field optical microscopy     tip-enhanced Raman spectroscopy     photo-induced force microscopy     molecular resonances     surface phonon polaritons     energy materials    

Design and optimization of reactive distillation: a review

《化学科学与工程前沿(英文)》 2022年 第16卷 第6期   页码 799-818 doi: 10.1007/s11705-021-2128-9

摘要: Reactive distillation process, a representative process intensification technology, has been widely applied in the chemical industry. However, due to the strong interaction between reaction and separation, the extension of reactive distillation technology is restricted by the difficulties in process analysis and design. To overcome this problem, the design and optimization of reactive distillation have been widely studied and illustrated for plenty of reactive mixtures over the past three decades. These design and optimization methods of the reactive distillation process are classified into three categories: graphical, optimization-based, and evolutionary/heuristic methods. The primary objective of this article is to provide an up-to-date review of the existing design and optimization methods. Desired and output information, advantages and limitations of each method are stated, the modification and development for original methodologies are also reviewed. Perspectives on future research on the design and optimization of reactive distillation method are proposed for further research.

关键词: reactive distillation     process intensification     design method     reactive phase diagram     optimization algorithm    

Passive convergence-permeable reactive barrier (PC-PRB): An effective configuration to enhance hydraulic

《环境科学与工程前沿(英文)》 2022年 第16卷 第12期 doi: 10.1007/s11783-022-1591-y

摘要:

● A novel PRB configuration based on passive convergent flow effect was proposed.

关键词: Passive convergence-permeable reactive barrier (PC-PRB)     Permeable reactive barrier configuration     Numerical simulation     Hydraulic performance evaluation     Sensitivity analysis    

Modeling limit force capacities of high force to volume lead extrusion dampers

《结构与土木工程前沿(英文)》 2021年 第15卷 第3期   页码 609-622 doi: 10.1007/s11709-021-0724-x

摘要: Lead extrusion dampers are supplemental energy-dissipation devices that are used to mitigate seismic structural damage. Small volumetric sizes and high force capacities define high-force-to-volume (HF2V) devices, which can absorb significant response energy without sacrificial damage. However, the design of such devices for specific force capacities has proven difficult based on the complexities of their internal reaction mechanisms, leading to the adoption of empirical approaches. This study developed upper- and lower-bound force capacity estimates from analytical mechanics based on direct and indirect metal extrusion for guiding design. The derived equations are strictly functions of HF2V device geometric parameters, lead material properties, and extrusion mechanics. The upper-bound estimates from direct and indirect extrusion are denoted as (FUB,1, FUB,2) and (FUB,3, FUB,4), respectively, and the lower-bound estimates are denoted as (FLB, FLB,1) based on the combination of extrusion and friction forces. The proposed models were validated by comparing the predicted bounds to experimental force capacity data from 15 experimental HF2V device tests. The experimental device forces all lie above the lower-bound estimates (FLB, FLB,1) and below the upper-bound estimates (FUB,1, FUB,2, FUB,4). Overall, the (FLB, FUB,2) pair provides wider bounds and the (FLB,1, FUB,4/FUB,1) pair provides narrower bounds. The (FLB,1, FUB,1) pair has a mean lower-bound gap of 36%, meaning the lower bound was 74% of the actual device force on average. The mean upper-bound gap was 33%. The bulge area and cylinder diameter of HF2V devices are key parameters affecting device forces. These relatively tight bounds provide useful mechanics-based predictive design guides for ensuring that device forces are within the targeted design range after manufacturing.

关键词: extrusion     lead dampers     upper and lower bound     analytical modelling     limit force    

Review of pantograph and catenary interaction

Weihua ZHANG, Dong ZOU, Mengying TAN, Ning ZHOU, Ruiping LI, Guiming MEI

《机械工程前沿(英文)》 2018年 第13卷 第2期   页码 311-322 doi: 10.1007/s11465-018-0494-x

摘要:

The application of electrified railway directly promotes relevant studies on pantograph-catenary interaction. With the increase of train running speed, the operating conditions for pantograph and catenary have become increasingly complex. This paper reviews the related achievements contributed by groups and institutions around the world. This article specifically focuses on three aspects: The dynamic characteristics of the pantograph and catenary components, the systems’ dynamic properties, and the environmental influences on the pantograph-catenary interaction. In accordance with the existing studies, future research may prioritize the task of identifying the mechanism of contact force variation. This kind of study can be carried out by simplifying the pantograph-catenary interaction into a moving load problem and utilizing the theory of matching mechanical impedance. In addition, developing a computational platform that accommodates environmental interferences and multi-field coupling effects is necessary in order to further explore applications based on fundamental studies.

关键词: electrified railway     pantograph and catenary interaction     contact force variation     moving load problem     mechanical impedance     multi-field    

静电力驱动的悬臂梁微型电场传感器件 Article

韩志飞, 胡军, 李立浧, 何金良

《工程(英文)》 2023年 第24卷 第5期   页码 184-191 doi: 10.1016/j.eng.2022.06.017

摘要:

随着智能电网和能源互联网的发展,大规模实时电压/电场监测成为电力系统的迫切需求,这依赖于先进传感器件的大规模布置。电场测量在电力系统中具有重要意义。一方面,基于电场测量的电压反演可以实现高电压的非接触式测量,替代传统高压互感器,从而减少测量设备绝缘成本和安装难度;另一方面,电场测量还可以被应用于设备故障诊断、雷电预警、电磁环境测量等应用场景。传统的电场测量设备,如场磨等,往往体积大、成本高,无法大规模灵活布置。本文提出了一种静电力驱动的压阻式微型电场传感器。传感器被设计为四悬臂结构,悬臂在静电力的驱动下产生位移和应变,通过压阻材料转化为可测信
号。所提出的传感器具有尺寸小、成本低、功耗低、易于批量生产的优点。同时,该传感器还具有高信噪比、高分辨率及宽电场测量范围的特点。实验结果表明,所提出的传感器具有1.1~1100.0 kV·m−1的线性测量范围、112 V·m−1·Hz−1/2的交流电场分辨率以及496 Hz的截止频率。这一微型电场传感器将在智能电网及能源互联网中具有广泛的应用价值。

关键词: 微型传感器     电气传感器件     微加工工艺     压阻器件    

Preparation of nZVI embedded modified mesoporous carbon for catalytic persulfate to degradation of reactive

《环境科学与工程前沿(英文)》 2021年 第15卷 第5期 doi: 10.1007/s11783-020-1372-4

摘要:

• The MCNZVI is prepared as an interesting material for PS activation.

关键词: MCNZVI     Core-shell structure     Reactive Black 5     Persulfate     Mechanism    

GASEOUS REACTIVE NITROGEN LOSSES FROM ORCHARDS, VEGETABLES AND TEA PLANTATIONS

《农业科学与工程前沿(英文)》 2023年 第10卷 第2期   页码 155-166 doi: 10.15302/J-FASE-2022477

摘要:

● Gaseous N emissions from orchards, vegetables and tea plantations (OVT) are reviewed.

关键词: fruit     greenhouse gas     green development     fertilizer management     climate change    

标题 作者 时间 类型 操作

Development, applications and challenges of ReaxFF reactive force field in molecular simulations

You Han, Dandan Jiang, Jinli Zhang, Wei Li, Zhongxue Gan, Junjie Gu

期刊论文

formation mechanisms in the cathode-electrolyte interface layer of lithium manganese oxide batteries from reactiveforce field (ReaxFF) based molecular dynamics

Sahithya REDDIVARI, Christian LASTOSKIE, Ruofei WU, Junliang ZHANG

期刊论文

styrene-butadiene-styrene copolymer on the aging resistance of asphalt: An atomistic understanding from reactive

期刊论文

Validation of polarizable force field parameters for nucleic acids by inter-molecular interactions

Liaoran Cao,Hong Ren,Jing Miao,Wei Guo,Yan Li,Guohui Li

期刊论文

Atomistic understanding of interfacial processing mechanism of silicon in water environment: A ReaxFF

期刊论文

论零点振动能与Casimir力

黄志洵

期刊论文

基于变形力监测数据的残余应力场推断和表征方法

赵智伟, 刘长青, 李迎光, James Gao

期刊论文

Review: Tip-based vibrational spectroscopy for nanoscale analysis of emerging energy materials

Amun JARZEMBSKI, Cedric SHASKEY, Keunhan PARK

期刊论文

Design and optimization of reactive distillation: a review

期刊论文

Passive convergence-permeable reactive barrier (PC-PRB): An effective configuration to enhance hydraulic

期刊论文

Modeling limit force capacities of high force to volume lead extrusion dampers

期刊论文

Review of pantograph and catenary interaction

Weihua ZHANG, Dong ZOU, Mengying TAN, Ning ZHOU, Ruiping LI, Guiming MEI

期刊论文

静电力驱动的悬臂梁微型电场传感器件

韩志飞, 胡军, 李立浧, 何金良

期刊论文

Preparation of nZVI embedded modified mesoporous carbon for catalytic persulfate to degradation of reactive

期刊论文

GASEOUS REACTIVE NITROGEN LOSSES FROM ORCHARDS, VEGETABLES AND TEA PLANTATIONS

期刊论文