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An empirical model for high energy density lithium-(ion)batteries with ultra-thick electrodes

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Tungsten 2024年第1期6卷 230-237页

作者： Li-Ming Jin Guang-Guang Xing Nan Qin Yan-Yan Lu Jun-Sheng Zheng Cun-Man Zhang Jim P.Zheng School of Automotive Studies and Clean Energy Automotive Engineering Center Tongji UniversityShanghai 201804China Department of Electrical Engineering University at BuffaloThe State University of New YorkBuffaloNY 14260USA

Increasing the electrode thickness is a significant method to decrease the weight and volume ratio of the inactive components for high energy density of the *** this contribution,we extracted a repeating unit in the configurations and establish the empirical energy density model based on some *** this model,the effects of the electrode thickness on the energy density for lithium-ion batteries(LIBs),lithium metal batteries(LMBs),and anode-free lithium batteries(ALBs)are evaluated quantitively with the current parameters of the *** results demonstrate that the structure evolutions from LIBs,LMBs to ALBs with the reduction of the anode weight contribution,the energy density can be well improved *** the increase of the thickness of the electrode provide another route to furthe r enhance the energydensity by decreasing the weight contribution of inactive materials;meanwhile the effects for ALBs are higher than LMBs and LIBs due to the higher weight ratio of inactive *** empirical energy density model is also applied into the practical system and provide intuitional results to guide the battery design for higher energy density.

关键词： empirical model High energy density Lithium batteries Ultra-thick electrodes

Estimation of pore volumes to breakthrough number in limestone cores by derivation of an empirical model

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Petroleum Research 2021年第3期6卷 264-270页

作者： Sina Lohrasb Radzuan Junin Department of Petroleum Engineering School of Chemical and Energy EngineeringFaculty of EngineeringUniversiti Teknologi MalaysiaUTM81310Johor BahruMalaysia Institute for Oil and Gas Universiti Teknologi Malaysia81310Johor BahruMalaysia

Acidizing in carbonate formations is an inevitable stimulation treatment method for oil and gas *** the limestone,acidizing stimulation makes capillary wormholes to increase fluids flow reservoir pro*** pore volume to breakthrough number is one of the main indexes for recognizing the wormhole ***,finding the pore volume to breakthrough number is one of the main goals in the limestone *** this number is always required for experimental works,which needs time,energy and *** purpose of this research is to develop an empirical method to estimate an acceptable result for this number merely by implementing limestone core and acid properties without any experimental *** order to create a wormhole,an empirical method is developed using the law of conservation of mass considering that the core of limestone as an isolated package and the overall mass is constant in this package in the acidizing ***,to develop the mathematical section,the Damk€ohler number is *** this number must be calculated experimentally,a constant number is created in the model to eliminate the Damkohler *** average accuracy of 92.31%is obtained for the developed empirical model by comparing the results obtained from the other three experimental and numerical *** study conclusively provides a thoroughly empirical method for estimating a high accuracy of the pore volume to breakthrough number by only using known physical properties limestone core and acid.

关键词： Acidizing Pore volumes to breakthrough Limestone Wormhole empirical model

An empirical model for Estimating Stratospheric Ozone Vertical Distributions over China

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Advances in Atmospheric Sciences 2009年第2期26卷 352-358页

作者：杨景梅邱金桓 Key Laboratory of Middle Atmosphere and Global Environment Observation (LAGEO) Institute of Atmospheric PhysicsChinese Academy of Sciences

Based on the Stratospheric Aerosol and Gas Experiment （SAGE） Ⅱ and the Halogen Occultation Experiment （HALOE） ozone profiles and the Total Ozone Mapping Spectrometer （TOMS） total ozone data sets, an empirical model for estimating the vertical distribution of stratospheric ozone over China is proposed. By using this model, the vertical distribution of stratospheric （16-50 km） ozone can be estimated according to latitude, month and total ozone. Comparisons are made between the modeled ozone profiles and the SAGEII/HALOE monthly mean ozone measurements, and the results show that the model calculated ozone concentrations conform well with the SAGEII/HALOE measured values, with the differences being less than 15% between 16 km and 18 km, less than 5% between 19 km and 40 km, and less than 10% between 41 km and 50 kin. Comparisons of the model results with balloon-borne ozonesonde measurements performed in Beijing also show good agreement, within 5%, at altitudes between 19 km and 30 km.

关键词： ozone vertical distribution empirical model

An empirical model for Estimating the Zonal Mean Aerosol Extinction Profiles from SAGE II Measurements

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Atmospheric and Oceanic Science Letters 2014年第6期7卷 553-558页

作者： YANG Jing-Mei ZONG Xue-Mei Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of Sciences

This paper presents an empirical model for estimating the zonal mean aerosol extinction profiles in the stratosphere over 10°-wide latitude bands between 60°S and 60°N, on the basis of Stratospheric Aerosol and Gas Experiment(SAGE) II aerosol extinction measurements at 1.02, 0.525, and 0.452 μm during the volcanically quiescent period between 1998–2004. First, an empirical model is developed for calculating the stratospheric aerosol extinction profiles at 1.02 μm. Then, starting from the 1.02 μm extinction profile and an exponential spectral dependence, an empirical algorithm is developed that allows the aerosol extinction profiles at other wavelengths to be calculated. Comparisons of the model-calculated aerosol extinction profiles at the wavelengths of 1.02, 0.525, and 0.452 μm and the SAGE II measurements show that the model-calculated aerosol extinction coefficients conform well with the SAGE II values, with the relative differences generally being within 15% from 2 km above the tropopause to 40 km. The model-calculated stratospheric aerosol optical depths at the three wavelengths are also in good agreement with the corresponding optical depths derived from the SAGE II measurements, with the relative differences being within 0.9% for all latitude bands. This paper provides a useful tool in simulating zonal mean aerosol extinction profiles, which can be used as representative background stratospheric aerosols in view of atmospheric modeling and remote sensing retrievals.

关键词： aerosol extinction coefficient stratosphere empirical model

Efficient calculation of fluid-induced wall shear stress within tissue engineering scaffolds by an empirical model

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Medicine in Novel Technology and Devices 2023年第2期18卷 267-271页

作者： Husham Ahmed Matthew Bedding-Tyrrell Davide Deganello Zhidao Xia Yi Xiong Feihu Zhao Zienkiewicz Centre for Computational Engineering and Department of Biomedical Engineering Faculty of Science&EngineeringSwansea UniversitySwanseaSA18ENUK Welsh Centre for Printing and Coating Faculty of Science and EngineeringSwansea UniversitySwanseaSA18ENUK Centre for Nanohealth Swansea University Medical School and Faculty of MedicineHealth and Life ScienceSwansea UniversitySwanseaSA35AUUK School of System Design and Intelligent Manufacturing Southern University of Science and TechnologyShenzhen518055China

Mechanical stimulation,such as fluid-induced wall shear stress(WSS),is known that can influence the cellular ***,in some tissue engineering experiments in vitro,mechanical stimulation is applied via bioreactors to the cells in cell culturing to study cell physiology and *** 3D cell culturing,porous scaffolds are used for housing the *** is known that the scaffold porous geometries can influence the scaffold permeability and internal WSS in a bioreactor(such as perfusion bioreactor).To calculate the WSS generated on cells within scaffolds,usually computational fluid dynamics(CFD)simulation is ***,the limitations of the computational method for WSS calculation are:(i)the high time cost of the CFD simulation(in particular for the highly irregular geometries);(ii)accessibility to the CFD model for some cell culturing experimentalists due to the knowledge *** address these limitations,this study aims to develop an empirical model for calculating the WSS based on scaffold *** model can allow the tissue engineers to efficiently calculate the WSS generated within the scaffold and/or determine the bioreactor loading without performing the computational simulations.

关键词： Wall shear stress Permeability empirical model Tissue engineering scaffold Bioreactor

Prediction of salinity intrusion in the sheltered estuary of Terengganu River in Malaysia using 1-D empirical intrusion model

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Acta Oceanologica Sinica 2017年第5期36卷 57-66页

作者： LEE Hin Lee TANGANG Fredolin GISEN Jacqueline Isabella SURATMAN Saim Research Centre for Tropical Climate Change Faculty of Science and TechnologyThe National University of MalaysiaUKM Bangi 43600Malaysia Research Centre for Water Quality and Environment National Hydraulic Research Institute of MalaysiaMinistry of Natural Resources and EnvironmentSeri Kembangan 43300Malaysia Centre for Earth Resources Research and Management Faculty of Civil Engineering and Earth ResourcesThe Universiti Malaysia PahangPahang 26600Malaysia

Generally one dimensional （l-D） empirical salinity intrusion model is limited to natural alluvial estuary. However, this study attempts to investigate its ability to model a sheltered alluvial estuary of the Terengganu River in Malaysia. The constructed breakwater at the mouth of the river shelters the estuary from direct influence of the open sea. The salinity density along the estuary was collected during the wet and dry seasons for scenarios before and after the constructed breakwater. Moreover, the freshwater discharges, tidal elevations and bathymetry data were also measured as model inputs. A good fit was demonstrated between simulated and observed variables, namely salinity distribution and intrusion length for both scenarios. Thus, the results show that 1-D empirical salinity model can be utilized for sheltered estuarine condition at the Terengganu Estuary, but with an appropriate determination of an initial point. Furthermore, it was observed that the salinity intrusion in the study area is largely dependent on the freshwater discharge rather than tidal elevation fluctuations. The scale of the salinity intrusion length in the study area is proportional to the river discharge of the -1/2 power. It was appeared that the two lines of the 1-D empirical salinity model and discharge power based equation fitted well to each other, with the average predicted minimum freshwater discharge of 150 m^3/s is going to be required to maintain acceptable salinity levels during high water slack （HWS） near the water intake station, which is located at 10.63 km from river mouth.

关键词： salinity intrusion sheltered estuary freshwater discharge geometric characteristic empirical model

TIME-IGGCAS model validation:Comparisons with empirical models and observations

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TIME-IGGCAS model validation:Comparisons with empirical mode...

Improved empirical DC I-V model for 4H-SiC MESFETs

中国科学院地质与地球物理研究所2008学术年会

作者： YUE XinAn~(1,2,3),WAN WeiXing~(1+),LIU LiBo~1,NING BaiQi~1,ZHAO BiQiang~1 & ZHANG ManLian~1 1 Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China 2 Wuhan Institute of Physics and Mathematics,Chinese Academy of Sciences,Wuhan 430071,China 3 Graduate University,Chinese Academy of Sciences,Beijing 100049,China

The TIME-IGGCAS(Theoretical Ionospheric model of the Earth in Institute of Geology and Geophysics,Chinese Academy of Sciences) has been developed recently on the basis of previous *** test its validity,we have made comparisons of model results with other typical empirical ionospheric models(IRI, NeQuick-ITUR,and Tltheridge temperature models) and multi-observations(GPS, lonosondes,Topex,DMSP,FORMOSAT,and CHAMP) in this *** conclusions are obtained from our *** modeled electron density and electron and ion temperatures are quantitatively in good agreement with those of empirical models and ***-IGGCAS can model the electron density variations versus several factors such as local time,latitude,and season very well and can reproduce most anomalistic features of ionosphere including equatorial anomaly,winter anomaly,and semiannual *** results imply a good base for the development of ionospheric data assimilation model in the future. TIME-IGGCAS underestimates electron temperature and overestimates ion temperature in comparison with either empirical models or *** model results have relatively large deviations near sunrise time and sunset time and at the low *** results give us a reference to improve the model and enhance its performance in the future.

关键词： ionosphere theoretical model empirical model satellite observation relative deviation

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Science in China(Series F) 2008年第8期51卷 1184-1192页

作者： CAO QuanJun ZHANG YiMen ZHANG YuMing LV HongLiang WANG YueHu TANG XiaoYan GUO Hui Key Lab of Education Ministry for Wide Band-Gap Semiconductor Materials and Devices Microelectronics Institute of Xidian University Xi'an 710071 China

A novel empirical large signal direct current （DC）Ⅰ-Ⅴ model is presented considering the high saturation voltage, high pinch-off voltage, and wide operational range of drain voltage for 4H-SiC MESFETs. A comparison of the presented model with Statz, Materka, Curtice-Cubic, and recently reported 4H-SiC MESFET large signal Ⅰ-Ⅴ models is made through the Levenberg-Marquardt method for fitting in nonlinear regression. The results show that the new model has the advantages of high accuracy, easily making initial value and robustness over other models. The more accurate results are obtained by the improved channel modulation and saturation voltage coefficient when the device is operated in the sub-threshold and near pinch-off region. In addition the new model can be implemented to CAD tools directly, using for design of 4H-SiC MESFET based RF＆MW circuit, particularly MMIC （microwave monolithic integrate circuit）.

关键词： 4H-SiC MESFET DC Ⅰ-Ⅴ characteristics empirical model Levenberg-Marquardt method nonlinear regression

empirical modeling of normal/cyclo-alkanes pyrolysis to produce light olefins

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Chinese Journal of Chemical Engineering 2022年第2期35卷 389-398页

作者： Xu Hou Bochong Chen Zhenzhou Ma Jintao Zhang Yuanhang Ning Donghe Zhang Liu Zhao Enxian Yuan Tingting Cui School of Chemical Engineering Changchun University of TechnologyChangchun 130012China Advanced Institute of Materials Science Changchun University of TechnologyChangchun 130012China School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225009China Department of Chemistry Tsinghua UniversityBeijing 100084China

Due to the complexity of feedstock,it is challenging to build a general model for light olefins *** work was intended to simulate the formation of ethylene,propene and 1,3-butadiene in alkanes pyrolysis by referring the effects of normal/***,the pyrolysis of n-pentane,n-hexane,n-heptane,n-octane,n-nonane,n-decane,cyclohexane,methylcyclohexane,n-hexane and cyclohexane mixtures,and n-heptane and methylcyclohexane mixtures were carried out at 650–800℃,and a particular attention was paid to the measurement of ethylene,propene and 1,***,pseudo-first order kinetics was taken to characterize the pyrolysis process,and the effects of feedstock composition were *** was found that chain length and cyclo-alkane content can be qualitatively and quantitively represented by carbon atom number and pseudo-cyclohexane content,which made a significant difference on light olefins ***,the inverse proportional/quadratic function,linear function and exponential function were proposed to simulate the effects of chain length,cycloalkane content and reaction temperature on light olefins formation,*** the obtained empirical model well reproduced feedstock conversion,ethylene yield and propene yield in normal/cycloalkanes pyrolysis,it exhibited limitations in simulating 1,3-butadiene ***,the accuracy and flexibility of the present model was validated by predicting light olefins formation in the pyrolysis of multiple hydrocarbon *** prediction data well agreed with the experiment data for feedstock conversion,ethylene yield and propene yield,and overall characterized the changing trend of 1,3-butadiene yield along with reaction temperature,indicating that the present model could basically reflect light olefins production in the pyrolysis process even for complex feedstock.

关键词： empirical model Normal-alkane Cyclo-alkane Pyrolysis Light olefins