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Quality evaluation and calibration of the SWIM significant wave height product with buoy data

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Acta Oceanologica Sinica 2021年第10期40卷 187-196页

作者： jing Ye Yong Wan Yongshou dai College of Control Science and Engineering China University of PetroleumQingdao 266580China College of Oceanography and Space Informatics China University of PetroleumQingdao 266580China

The significant wave height(SWH)is one of the main parameters that describe wave characteristics and is widely used in wave research *** parameters measured by radar are influenced by the offshore distance and sea *** and calibration are of great significance for radar data *** nadir beam of surface wave investigation and monitoring(SWIM)detects the global-ocean-surface *** determine the product quality of SWIM SWH,this paper carried out time-space matching between SWIM and buoy *** data qualities were evaluated under different offshore distances and sea *** improved calibration method was proposed based on sea state segmentation,which considered the distribution of the point collocation numbers in various sea *** results indicate that(1)the SWIM SWH accuracy at offshore distances greater than 50 km is higher than that at distances less than 50 km,with an root mean squared error(RMSE)of 0.2444 m,scatter index(SI)of 0.1156 and relative error(RE)of 9.97%at distances greater than 50 km and those of 0.4460 m,0.2230 and18.66%at distances less than 50 km.(2)SWIM SWH qualities are better in moderate and rough sea states with RMSEs of 0.2848 m and 0.3169 m but are worse in slight and very rough sea states.(3)The effect of the improved calibration method is superior to the traditional method in each sea state and overall data,and the RMSE of SWIM SWH is reduced from the raw 0.3135 m to 0.2859 m by the traditional method and 0.1982 m by the improved *** influence of spatiotemporal window selection on data quality evaluation was analyzed in this *** paper provides references for SWIM SWH product applications.

关键词： significant wave height SWIM buoy validation calibration

Interaction Between Cytochrome c and the Hapten 2,4-Dinitro- fluorobenzene by Electrospray Ionization Mass Spectrometry

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Chinese Journal of Chemical Physics 2008年第3期21卷 217-220页

作者： Bo Wu Yan-qiu Chu Zhao-yun dai chuan-fan Ding Physical Chemistry Institute Department of Chemistry Fudan University Shanghai 200433 China Infectious Disease Department Huadong Hospital Shanghai 200040 China

Allergic contact dermatitis is a delayed hypersensitivity reaction, which results from skin exposure to low molecular weight chemicals such as haptens. To clarify the pathogenic mechanism, electrospray ionization mass spectrometry （ESI-MS） and hydrogen/deuterium （H/D） exchange, as well as UV spectroscopy, were applied to determine the interaction between the model protein cytochrome c （cyt c） and the hapten 2,4- dinitro-fiuorobenzene （DNFB）. The ESI-MS results demonstrate that the conformation of cyt c can change from native folded state into partially unfolded state with the increase of DNFB. The equilibrium state H/D exchange followed by ESI-MS further confirms the above results. UV spectroscopy indicates that the strong- field coordination between iron of heme （prosthetic group） and His18 or Met80 of cyt c is not obviously affected by the hapten.

关键词： Interaction Cytochrome c 2 4-dinitro-fluorobenzene ESI-MS

AN ADAPTIVE CONTROL STRATEGY FOR PROPER MESH DISTRI-BUTION IN LARGE EDDY SIMULATION

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Journal of Hydrodynamics 2010年第6期22卷 865-870页

作者： ZHANG Bin WANG Tong GU chuan-gang dai Zheng-yuan Key Laboratory for Power Machinery and Engineering of Ministry of Education Shanghai Jiao Tong University Shanghai 200240 China Trane＇s Asia-Pacific Research Center Shanghai 200001 China

The Filtering Grid Scale （FGS） of sub-grid scale models does not match with the theoretical Proper FGS （PFGS） because of the improper mesh. Therefore, proper Large Eddy Simulation （LES） Mesh is very decisive for better results and more economical cost. In this work, the purpose is to provide an adaptive control strategy for proper LES mesh with turbulence theory and CFD methods. A new expression of PFGS is proposed on the basis of -5/3 law of inertial sub-range and the proper mesh of LES can be built directly from the adjustment of RANS mesh. A benchmark of the backward facing step flow at Re = 5147 is provided for application and verification. There are three kinds of mesh sizes, including the RANS mesh, LAM （LES of adaptive-control mesh）, LFM （LES of fine mesh）, employed here. The grid number of LAM is smaller than those of LFM evidently, and the results of LAM are in a good agreement with those of DNS and experiments. It is revealed that the results of LAM are very close to those of LFM. The conclusions provide positive evidences for the novel strategy.

关键词： Large Eddy Simulation (LES) Proper Filtering Grid Scale (PFGS) turbulence -5/3 law adaptive control

THE THIXOTROPY-LOOP BEHAVIORS OF AN LDPE MELT:EXPERIMENT AND SIMPLE ANALYSIS

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Journal of Hydrodynamics 2006年第6期18卷 666-675页

作者： HUANG Shu-xin LU chuan-jing Department of Engineering Mechanics Shanghai Jiaotong University Shanghai 200030 China

The time-dependent viscoelastic behaviors of an Low-Density-Pdyethyene（LDPE）（PE-FSB-23D022） melt were experimentally investigated using two types of thixotropy-loop test i.e., the triangular- and the trapezoidal-loop shear test. The shear strengthening was noted in the thixotropy-loop tests not only at high shear rate but also at low shear rate, and it was found that the dimensionless stress amplitude of shear strengthening at low shear rate is larger than that at high shear rate. Moreover, the shear strengthening is a time-dependent viscoelastic behavior that is observed during the initial stage of shearing, and it cannot be found when the time interval corresponding to the increase in shear rate is sufficiently long, The remarkable shear-weakening phenomenon was noticed at higher shear rate when shearing time is prolonged. Five types of the triangular thixotropy-loop results were marked in terms of the configurations of the stress-rate curves, which indicate the complex features of the time-dependent viscoelasticity. A simple model was used to describe the thixotropy-loop tests, and the fitted results showed good agreement with the experimental results.

关键词： thixotropy-loop test time-dependent viscoelasticity LDPE shear strengthening shear weakening

First-principles calculations of structural,elastic and electronic properties of(TaNb)0.67(HfZrTi)0.33 high-entropy alloy under high pressure

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International Journal of Minerals,Metallurgy and Materials 2020年第10期27卷 1405-1414页

作者： Zhi-sheng Nong Hao-yu Wang jing-chuan Zhu School of Materials Science and Engineering Shenyang Aerospace UniversityShenyang 110136China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

To clarify the effect of pressure on a(TaNb)0.67(HfZrTi)0.33 alloy composed of a solid solution with a single body-centered-cubic crystal structure,we used first-principles calculations to theoretically investigate the structural,elastic,and electronic properties of this alloy at different *** results show that the calculated equilibrium lattice parameters are consistent with the experimental results,and that the normalized structural parameters of lattice constants and volume decrease whereas the total enthalpy differenceΔE and elastic constants increase with increasing ***(TaNb)0.67(HfZrTi)0.33 alloy exhibits mechanical stability at high pressures lower than 400 *** high pressure,the bulk modulus B shows larger values than the shear modulus G,and the alloy exhibits an obvious anisotropic feature at pressures ranging from 30 to 70 *** analysis of the electronic structures reveals that the atomic orbitals are occupied by the electrons change due to the compression of the crystal lattices under the effect of high pressure,which results in a decrease in the total density of states and a wider electron energy *** factor is favorable for zero resistance.

关键词： first-principles calculations elastic property electronic structure density of states high-entropy alloys high pressure

槟榔干燥动力学模型及微观结构、代谢物变化规律研究

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热带作物学报 2025年第1期46卷 222-235页

作者：张晶代佳慧王世萍代文婷康效宁吉建邦胡玉娟海南省农业科学院三亚研究院海南三亚572000 海南省农业科学院农产品加工设计研究所海南海口570100 海口市槟榔加工研究重点实验室海南海口570100

干燥是槟榔加工的第1步,干燥过程直接影响槟榔的品质和货架期。为了明确槟榔热风干燥过程的水分变化、纤维微观结构及代谢物的变化规律,以期对槟榔干燥时间进行精准调控。本研究以槟榔鲜果和槟榔杀青果为研究对象,利用5种模型对不同温... 详细信息

干燥是槟榔加工的第1步,干燥过程直接影响槟榔的品质和货架期。为了明确槟榔热风干燥过程的水分变化、纤维微观结构及代谢物的变化规律,以期对槟榔干燥时间进行精准调控。本研究以槟榔鲜果和槟榔杀青果为研究对象,利用5种模型对不同温度下槟榔热风干燥曲线进行拟合,建立槟榔干燥动力学模型,同时利用扫描电子显微镜、LC-MS等探讨干燥过程中槟榔微观结构、代谢物的变化规律。结果表明:槟榔干燥曲线呈指数下降,干燥速率曲线分为加速和降速2个阶段,温度对干燥速率有显著影响;Page模型对槟榔热风干燥曲线拟合较好,模型决定系数(R^(2))在0.98以上,均方差(mean square deviation,RMSE)在0.02~0.06范围内,模型预测值和真实值差异不显著,可以较好地反映槟榔干燥过程中的水分变化规律。微观结构分析表明,随着干燥时间的增加槟榔纤维层变得致密、紧实,杀青处理导致槟榔纤维结构松散。质构结果表明,随着干燥时间的增加,槟榔硬度和咀嚼度增加,弹性降低。差异代谢物结果显示,干燥过程通过影响氨基酸代谢通路、中心碳代谢通路、亚油酸代谢通路、黄酮类生物合成、苯丙烷类生物合成进而影响有机酸、脂质和类脂分子等发生变化。研究结果为丰富槟榔加工基础研究,以及为槟榔热风干燥时间的选择提供理论依据。

关键词：槟榔干燥动力学模型微观结构代谢物质构

A New Dynamic-Copula Based Correlated Degradation Feature for Remaining Useful Life Prediction

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Chinese Journal of Electronics 2021年第1期30卷 36-44页

作者： LI Juan dai Hongde jing Bo JIAO Xiaoxuan College of Mathematics and Statistics Ludong University School of Basic Sciences for Aviation Naval Aviation University College of Aeronautics Engineering Air Force Engineering University

Feature extraction plays an important role in Remaining useful life(RUL) prediction. Feature extraction mainly depends on the performance degradation signal in the previous study, in which the dynamic correlations among different signals are ignored, and the RUL accuracy is affected. A new dynamic feature based on the correlations of the performance degradation signal is proposed. First, dynamic correlation coefficients are calculated by copula function as the multivariate correlation performance degradation features. Second,the random effect Wiener process is used for RUL prediction based on the new features, and the maximum likelihood estimation is adopted to calculate the unknown parameters of the Wiener process. Finally, the RUL estimation for solder joints under vibration load is carried out compared with the quantile and quantile-Principal component analysis(PCA) mixed feature extraction method. The research results show that the proposed method improved the prediction accuracy of RUL.

关键词： Bayes methods new dynamic-copula based correlated degradation feature vibrations performance degradation signal RUL prediction feature extraction random effect Wiener process RUL accuracy maximum likelihood estimation condition monitoring remaining life assessment multivariate correlation performance degradation features dynamic feature useful life prediction copula function stochastic processes dynamic correlations principal component analysis RUL estimation dynamic correlation coefficients

Review on inorganic-organic S-scheme photocatalysts

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Journal of Materials Science & Technology 2023年第34期165卷 187-218页

作者： jing Wang Zhongliao Wang Kai dai Jinfeng Zhang Key Laboratory of Green and Precise Synthetic Chemistry and Applications Ministry of EducationAnhui Province Key Laboratory of Pollutant Sensitive Materials and Environmental RemediationHuaibei Normal UniversityHuaibeiAnhui 235000China

The inorganic-organic S-scheme heterojunction photocatalyst demonstrates exceptional light absorption capacity,high photogenerated charge separation efficiency,and remarkable redox ability,while also inheriting diverse advantages of both inorganic and organic *** paper provides a comprehensive review of recent advances in photocatalysis in relation to the inorganic-organic S-scheme heterojunction ***,the fundamental aspects and benefits of the S-scheme heterojunction photocatalyst are outlined,followed by a discussion of several synthetic techniques for producing the inorganic-organic S-scheme heterojunction photocatalyst,as well as various advanced characterization methods that can verify the S-scheme heterojunction photocatalyst in both steady-state and transient *** impact of the inorganic-organic S-scheme heterojunction photocatalyst is illustrated with examples in fields such as carbon dioxide reduction,water splitting for hydrogen production,hydrogen peroxide synthesis,nitrogen fixation,organic pollutant degradation,organic transformation,and ***,suggestions are presented for designing the inorganic-organic S-scheme heterojunction photocatalyst and enhancing its photocatalytic ***,the inorganic-organic Sscheme heterojunction photocatalyst has emerged as a prominent and promising technology in the field of photocatalysis.

关键词： Photocatalysis S-scheme Inorganic-organic hybrid Application

Contact Electrification and Adhesion Between Carbon Nanotube and Graphene on Metal Surfaces: Insights from First-principles Study

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Journal of Bionic Engineering 2022年第1期19卷 103-112页

作者： jing Tao Linfeng Wang Jin Li Zhendong dai Jiangsu Provincial Key Laboratory of Bionic Functional Materials College of Mechanical and Electrical EngineeringNanjing University of Aeronautics and AstronauticsNanjing210016China College of Aerospace Engineering Nanjing University of Aeronautics and AstronauticsNanjing210016China

The effect of contact electrification on adhesion has been debated in recent years for gecko and bio-inspired dry adhesion *** understand the fundamentals of this issue for Carbon Nanotube(CNT)dry adhesives,contact electrification and its relationship with adhesion are systematically studied using the first-principles *** transfers from CNT or its special form,graphene,to the metal surface during the contact,and the transferred charge linearly correlates with the work function ***,the adhesion energy is linearly related to the transferred charge for both CNT and *** charge transfers from the flat graphene to metal surfaces than the curved CNT,leading to higher adhesion between graphene and metal *** curved structure of the CNT causes an irregular change of charge at the interface and hinders the charge ***,the curved structure induces electronic localization,which also decreases the interfacial charge *** structure affects contact electrification,and hence adhesion is further demonstrated by the CNT with different deformation when contacting different *** study advances our understanding of contact electrification and its relationship with adhesion at the interface for bio-inspired carbon adhesive materials and sheds light on the control of them for engineering applications.

关键词： Contact electrification Adhesion Bio-inspired adhesive CNT First-principles calculation Interfacial interaction