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Photodissociation Exploration for Near-Visible UV Absorption of Molecular Bromine

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Chinese Journal of Chemical Physics 2008年第1期21卷 12-20页

作者： dong-fang Zhang Bing Zhang State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Insti-tute of Physics and Mathematics Chinese Academy of Sciences Wuhan 430071 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

The photodissociation of Br2 was investigated within the near-visible UV absorption band. Based on the potential curves for the ground and low-lying excited states, the optical cross-sections for the discrete transitions of C1^Пu,B^3Пou^＋, A^3П1u←X^1∑g＋ and their total energy absorption spectrum are derived, and the quantum yield of （Br＋Br6＊） channel are determined correspondingly. The one-dimensional Landau-Zener model is used to evaluate the behavior of curve crossing during photodissociation. The results indicate that the influence of nonadiabatic mechanism, which may be caused by the electronic-vibrational interplay between the 13 and C states, is negligibly small for the （Br＋Br^＊） channel. From the Landau-Zener modeling of the observed product recoil parameter β（Br＋Br）, the best-fit value of the coupling matrix elenment or coupling strength between the diabatic B and C state potentials is obtained.

关键词： Photodissociation Time-dependent wave packet Nonadiabatic mechanism Landau-Zener model

Metal-halide perovskites for high-efficiency radiation shielding applications

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Light(Science & Applications) 2023年第1期12卷 8-9页

作者： Qingfeng dong Yanjun fang State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China State Key Laboratory of Silicon Materials and School of Materials Science and Engineering Zhejiang UniversityHangzhou 310027China

The ionizing radiation possesses extremely strong penetration capability,which poses serious risk on the health of the human body and jeopardize *** the authors demonstrate that MAPbl3/epoxy composites prepared by a s... 详细信息

关键词： composites perovskite halide

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高温下HMX热分解反应分子动力学模拟

原子与分子物理学报 2025年第2期42卷 105-110页

作者：陈芳贾方硕陈瑶李天浩郭国琦董羚中北大学化学与化工学院太原030051

本文采用ReaxFF-lg反应分子动力学方法研究了奥克托金(HMX)在六种不同温度下的初始反应热分解过程,验证了ReaxFF-lg势函数对HMX体系的适用性,计算了不同温度下HMX体系势能、总物种演化趋势、初始反应产物以及指前因子和活化能.结果表明,... 详细信息

本文采用ReaxFF-lg反应分子动力学方法研究了奥克托金(HMX)在六种不同温度下的初始反应热分解过程,验证了ReaxFF-lg势函数对HMX体系的适用性,计算了不同温度下HMX体系势能、总物种演化趋势、初始反应产物以及指前因子和活化能.结果表明,HMX热分解过程主要有三种初始分解机理:N-NO_(2)键的断裂,HONO的解离和主环上C-N键的断裂,计算得到的初始分解阶段活化能Ea和指前因子ln(A),与实验值相吻合.

关键词： HMX 反应分子动力学(RMD) ReaxFF-lg 热分解温度

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实时三维超声技术评价左心室心肌致密化不全患者左心房管道及助力泵功能

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生物医学工程与临床 2017年第3期21卷 262-266页

作者：李方方任卫东宋光吴丹刘开薇中国医科大学附属盛京医院超声科辽宁沈阳110004

目的应用实时三维超声技术对左心室心肌致密化不全(LVNC)患者左心房管道功能和助力泵功能进行研究,并探讨其在LVNC诊断的价值。方法选择有典型LVNC超声表现的患者(LVNC组)20例,其中男性7例,女性13例,年龄4~55岁,平均年龄32.8岁。4~16岁3... 详细信息

目的应用实时三维超声技术对左心室心肌致密化不全(LVNC)患者左心房管道功能和助力泵功能进行研究,并探讨其在LVNC诊断的价值。方法选择有典型LVNC超声表现的患者(LVNC组)20例,其中男性7例,女性13例,年龄4~55岁,平均年龄32.8岁。4~16岁3例,17~35岁9例,36~55岁8例。以20例年龄相匹配的健康人作为正常对照组。应用Philips iE33彩色多普勒超声诊断仪,采集二维左心测量值及三维左心心尖四腔切面full-volume图像,应用Qlab软件进行脱机分析。结果二维测量得出LVNC组与正常对照组在室间隔厚度、左心室舒张末内径及左心室收缩功能差异均无统计学意义(P>0.05)。管道功能:LVNC组左心房被动排空容积/体表面积(BSA)、左心房管道容积/BSA及左心房被动排空指数差异无统计学意义(P>0.05),表明LVNC组与正常对照组左心房管道功能无明显差异。助力泵功能:LVNC组左心房主动排空容积/BSA为(8.73±3.92)mL/m^2,明显高于正常对照组[(5.53±2.93)mL/m^2](P<0.01);LVNC组左心房主动排空指数为(51.27±9.68)%,明显高于对照组[(36.25±12.47)%](P<0.01)。结论 LVNC患者左心房助力泵功能增加,间接反映LVNC患者左心室舒张功能减低。应用实时三维超声技术可以对LVNC患者心脏功能进行评估。

关键词：心肌致密化不全实时三维超声左心房管道功能左心房助力泵功能

基于宽波段数据定量反演土壤有机质含量的研究

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湖北农业科学 2017年第18期56卷 3540-3544页

作者：陈旭李明葛芳芳陈东琼王延仓北华航天工业学院计算机与遥感信息技术学院河北廊坊065000 河北省航天遥感信息处理与应用协同创新中心河北廊坊065000

定量分析了北京顺义、通州区土壤高光谱反射特征,利用资源三号、高分一号、高分二号传感器的光谱响应函数,结合高光谱数据生成相应宽波段模拟数据;将土壤光谱数据、拟合宽波段数据分别与实测土壤有机质含量开展相关性分析,提取并筛选敏... 详细信息

定量分析了北京顺义、通州区土壤高光谱反射特征,利用资源三号、高分一号、高分二号传感器的光谱响应函数,结合高光谱数据生成相应宽波段模拟数据;将土壤光谱数据、拟合宽波段数据分别与实测土壤有机质含量开展相关性分析,提取并筛选敏感波段,利用偏最小二乘法建立基于高光谱数据的土壤有机质含量预测模型;依据宽波段模拟数据和实测土壤有机质含量的相关性,提取并筛选敏感波段,建立土壤有机质含量预测模型。结果表明,在基于土壤高光谱数据建立的土壤有机质含量预测模型中,以对数的一阶微分为最优,其R和RMSE分别为0.697和0.195,偏最小二乘法得到的反演土壤有机质含量的模型是可靠的;在基于模拟宽波段构建的土壤有机质含量估测模型中,以高分一号的拟合精度最高,R和RMSE分别为0.334和0.240;受室外不可控因素的影响,模拟宽波段数据在估测北方地区土壤有机质含量方面仍需进一步研究。

关键词：宽波段反射率模拟土壤有机质偏最小二乘

Equilibria and Stability Analysis of Cohen-Grossberg BAM Neural Networks on Time Scale

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Journal of Systems Science & Complexity 2022年第4期35卷 1348-1373页

作者： LIU Mingshuo fang Yong dong Huanhe College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao266590China

This paper considers the Cohen-Grossberg BAM neural networks(CG-BAMNNs) on time scale, which can unify and generalize the continuous and discrete systems. First, the criteria for the existence and uniqueness of the equilibrium of CG-BAMNNs are derived on time scale. Then based on that, the authors give the criteria for the stability and estimation of equilibrium of the CG-BAMNNs on time scale. The method proposed in this paper unifies and generalizes the continuous and discrete CGBAMNNs systems, and is applicable to some other neural network systems on time scale with practical meaning. The effectiveness of the proposed criteria for delayed CG-BAMNNs is demonstrated by numerical simulation.

关键词： Cohen-Grossberg BAM neural networks existence numerical simulation stability uniqueness

A New Method for Solving Nonlinear Partial Differential Equations Based on Liquid Time-Constant Networks

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Journal of Systems Science & Complexity 2024年第2期37卷 480-493页

作者： SUN Jiuyun dong Huanhe fang Yong College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao 266590China

In this paper,physics-informed liquid networks(PILNs)are proposed based on liquid time-constant networks(LTC)for solving nonlinear partial differential equations(PDEs).In this approach,the network state is controlled via ordinary differential equations(ODEs).The significant advantage is that neurons controlled by ODEs are more expressive compared to simple activation *** addition,the PILNs use difference schemes instead of automatic differentiation to construct the residuals of PDEs,which avoid information loss in the neighborhood of sampling *** this method draws on both the traveling wave method and physics-informed neural networks(PINNs),it has a better physical ***,the KdV equation and the nonlinear Schr¨odinger equation are solved to test the generalization ability of the *** the best of the authors’knowledge,this is the first deep learning method that uses ODEs to simulate the numerical solutions of PDEs.

关键词： Nonlinear partial differential equations numerical solutions physics-informed liquid networks physics-informed neural networks

INVESTIGATION OF THE FLOW IN FRACTAL RESERVOIR INCLUDING THE EFFECTS OF QUADRATIC GRADIENT TERM

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Journal of Hydrodynamics 2004年第4期16卷 474-480页

作者： YAOYue-dong LIXiang-fang TONGDeng-ke InstituteofPetroleumandGasEngineering UniversityofPetroleumBeijing102249China DepartmentofAppliedMathematics UniversityofPetroleumDongying257062China

According to the assumption of slightly compressible fluid, the quadraticgradient term in the nonlinear partial differential equations for the traditional well-test model isusually neglected. The linear partial differential equation is thus established. It is known thatneglecting the quadratic gradient term results in errors for long-time well tests. A nonlinear flowmodel for fractal medium is constructed and the quadratic gradient term is considered. The exactsolutions of the fractal reservoir models are obtained by Laplace transform and Weber transform in aconstant-rate and constant-pressure production for an infinitely large system. This paper addressesthe variation of pressure with fluid compressibility coefficient and fractal reservoir *** plots of the typical pressure curves are constructed, and the results can be applied towell-test analysis.

关键词： fractal model nonlinear exact solution typical curve plots well test

Microstructure and phase transformation of Ni_(56)Fe_(x)Ga_(44-x)(15≤x≤20)alloys

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Rare Metals 2024年第11期43卷 6048-6053页

作者： Cui-fang dong Jing-Min Wang Laboratory of Aerospace Materials and Performance(Ministry of Education) School of Materials Science and EngineeringBeihang UniversityBeijing 100191China

Ni_(56)Fe_(x)Ga_(44-x)(15≤x≤20)alloys were studied with the phase structure and magnetic *** martensitic transformation was observed over the whole composition *** martensitic transformation starting temperature(M_(s))increases from 256 K for x=15 to 350 K for x=18 and then decreases from 350 K for x=18 to333 K for x=20 by increasing substitution of Fe for *** austenitic Curie temperature((?))is observed for15≤x≤16 and 18≤x≤20,*** the martensitic Curie temperature(T^(A)_(X))is observed for x=*** 18

关键词： Ni-Fe-Ga Dual-phase Martensitic transformation Magnetic transition