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Homogenization for Periodic Heterogeneous Materials with Arbitrary Position-Dependent Material Properties

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Communications in Theoretical Physics 2012年第8期58卷 189-194页

作者：徐志杰 energy resource recovery & management Idaho National Laboratory Idaho Falls

We present a rigorous homogenization approach for elcient computation of a class of physical problems in a one-dimensional periodic heterogeneous material. This material is represented by a spatially periodic array of unit cells with a length of More specifically, the method is applied to the diffusion, heat conduction, and wave propagation problems. Heterogeneous materials can have arbitrary position-dependent continuous or discontinuous materials properties （for example heat conductivity） within the unit cell. The final effective model includes both effective properties at the leading order and high-order contributions due to the microscopic heterogeneity. A dimensionless heterogeneity parameter ~ is defined to represent high-order contributions, shown to be in the range of [-1/12, 0], and has a universal expression for all three problems. Both effective properties and heterogeneity parameter 13 are independent oft, the microscopic scale of heterogeneity. The homogenized solution describing macroscopic variations can be obtained from the effective model. Solution with sub-unit-cell accuracy can be constructed based on the homogenized solution and its spatial derivatives. The paper represents a general approach to obtain the effective model for arbitrary periodic heterogeneous materials with position-dependent properties.

关键词： diffusion conduction wave homogenization multi-scale upscaling dispersive

Chemically modified silica gel with 1-{4-[(2-hydroxy-benzylidene)amino]phenyl}ethanone:Synthesis, characterization and application as an efficient and reusable solid phase extractant for selective removal of Zn(Ⅱ) from mycorrhizal treated fly-ash samples

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Journal of Environmental Sciences 2013年第6期25卷 1252-1261页

作者： R.K.Sharma Aditi Puri Anil Kumar Alok Adholeya 2 Green Chemistry Network Centre Department of ChemistryUniversity of Delhi Biotechnology and management of Bioresources Division The Energy and Resource Institute

1-{4-[（2-hydroxy-benzylidene）amino]phenyl}ethanone functionalized silica gel was synthesized and used as a highly efficient, selective and reusable solid phase extractant for separation and preconcentration of trace amount of Zn（II） from environmental matrices. The adsorbent was characterized by fourier transform infrared spectroscopy （FT-IR）, elemental analysis,~3C CPMAS NMR spectroscopy, scanning electron microscopy （SEM）, thermogravimetric analysis （TGA） and BET surface area analysis. The dependence of zinc extraction on various analytical parameters such as pH, type and amount of eluent, sample flow rate and interfering ions were investigated in detail. The material exhibited superior adsorption efficiency for Zn（II） with high metal loading capacity of 1.0 mmol/g under optimum conditions. After adsorption, the recovery （〉 98%） of metal ions was accomplished using 1.0 mol/L HNO3 as an eluent. The sorbent was also regenerated by microwave treatment in milder acidic environment （0.1 mol/L HNO3）. The lower detection limit and preconcentration factor of the present method were found out to be 0.04 ~tg/L and 312.5 respectively. The modified silica surface possessed excellent selectivity for the target analytes and the adsorption/desorption process remained effective for at least ten consecutive cycles. The optimized procedure was successfully implemented for the extraction of Zn（II） from mycorrhizal treated fly ash and pharmaceutical samples with reproducible results.

关键词： solid phase extraction silica gel preconcentration fly-ash zinc

Detecting the Origins of Moisture over Southeast China:Seasonal Variation and Heavy Rainfall

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Advances in Atmospheric Sciences 2016年第3期33卷 319-329页

作者： Xiuzhen LI Wen ZHOU Yongqin David CHEN Department of Geography and resource management The Chinese University of Hong Kong Guy Carpenter Asia–Pacific Climate Impact Centre School of Energy and EnvironmentCity University of Hong Kong Department of Geography and resource management and Institute of EnvironmentEnergy and SustainabilityThe Chinese University of Hong Kong

To examine the ability of the Hybrid Single-Particle Lagrangian Integrated Trajectory （HYSPLIT） model to detect the origins and paths of moisture supplied to Southeast China, trajectories of air particles released over Southeast China were traced backward during 1 April 2012 to 31 March 2013 and three typical regional persistent heavy rainfall events. The HYSPLIT model provides more insightful information than water vapor flux. Analysis of the specific humidity along the trajectories revealed the origins of moisture and their contributions to the moisture supply in Southeast China. In the boreal summer half year, four key moisture transport paths from the eastern Indian Ocean, central Indian Ocean, South China Sea （SCS）, and western North Pacific （WNP） contribute 10%, 20%, 31%, and 16% of the moisture to Southeast China, respectively. In the winter half year, the contributions of the paths from the WNP and North China double. Examination of heavy rainfall events showed that under tropical storm conditions, all moisture transport routines are rotated cyclonically before reaching Southeast China. The invasion of cold air can trigger heavy rainfall in both the summer and winter half years but plays different roles： it does not contribute to the moisture supply but plays a key role in converging and uplifting the moisture in the summer half year, while it supplies a great amount of moisture in the winter half year as it absorbs abundant moisture in crossing the WNE

关键词： moisture origin Southeast China HYSPLIT seasonal variation heavy rainfall

In situ growth of a-few-layered MoS_(2)on CdS nanorod for high efficient photocatalytic H_(2)production

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Frontiers in energy 2021年第3期15卷 752-759页

作者： Wei CHEN Xiang LIU Shaojie WEI Qianqian HENG Binfen WANG Shilong LIU Li GAO Liqun MAO Henan Engineering Research Center of resource and energy recovery from Waste Henan UniversityKaifeng 475004China

An ultrathin MoS_(2)was grown on CdS nanorod by a solid state method using sulfur powder as sulfur source for photocatalytic H_(2)*** characterization result reveals that the ultrathin MoS_(2)nanosheets loaded on CdS has a good contact *** photoelectrochemical result shows that MoS_(2)not only are beneficial for charge separation,but also works as active sites,thus enhancing photocatalytic *** with pure CdS,the photocatalytic activity of MoS_(2)loaded CdS was significantly *** hydrogen evolution rate on m(MoS_(2)):m(CdS)=1:50(m is mass)reaches 542μmol/h,which is 6 times of that on pure CdS(92μmol/h).This work provides a new design for photocatalysts with high photocatalytic activities and provides a deeper understanding of the effect of MoS_(2)on enhancing photocatalytic activity.

关键词： photocatalytic H_(2)production CdS MoS_(2)cocatalyst charge separation

Red mud-based catalysts for the catalytic removal of typical air pollutants: A review

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Journal of Environmental Sciences 2023年第5期127卷 628-640页

作者： Jiawei Chen YaoWang Zhiming Liu State Key Laboratory of Chemical resource Engineering Beijing University of Chemical TechnologyBeijing 100029China Beijing Center for Environmental Pollution Control and resource recovery Beijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of energy Environmental Catalysis Beijing University of Chemical TechnologyBeijing 100029China

Red mud,as a solid waste produced during the alumina production,can cause severe ecoenvironmental pollution and health risks to ***,the resourcing of this type of solid waste is an effective way for the sustainable *** paper reviews the recent progress on red mud-based catalysts for the removal of typical air pollutants,such as the catalytic reduction of nitrogen oxides(NO_(x))by NH_(3)(NH_(3)-SCR)and the catalytic oxidation of CO and volatile organic compounds(VOCs).The factors influencing the catalytic performance and the structure–activity relationship have been *** prospects and directions for the development of such catalysts are also *** review would benefit for the high value-added utilizations of red mud in mitigating atmospheric pollutions.

关键词： Red mud Catalyst NH_(3)-SCR Catalytic oxidation Air pollutants

The Pioneering Works of Professor Duzheng YE on Atmospheric Dispersion,Tibetan Plateau Meteorology,and Air–Sea Interaction

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Advances in Atmospheric Sciences 2017年第10期34卷 1137-1149页

作者： Ngar-Cheung LAU Institute of Environment Energy and Sustainabilityand Department of Geography and Resource ManagementThe Chinese University of Hong KongShatinN.T.Hong Kong

This paper provides an overview of the impacts of the original works of Professor Duzheng YE on a selected set of observational and model studies with which the present author has been associated over the past several decades. The main themes of these works include atmospheric energy dispersion, air–land interactions over the Tibetan Plateau, and El Ni n？orelated air–sea coupling over East *** dispersive behavior of observed atmospheric fluctuations accompanying cold surge events in East Asia is demonstrated. Cold air outbreaks over Korea and southern China are coincident with the successive downstream development of troughs and ridges, with the group velocity of such wave packets being notably faster than the phase propagation speed of individual troughs and ridges. In a more general context, dispersive features are also discernible from lagged teleconnection charts and cross-spectra of observed and model-simulated geopotential height variations on 10–30-day time *** the output from a high-resolution general circulation model, the relative contributions of condensational, sensible, and radiative heating to the atmospheric energy budget over the Tibetan Plateau are documented. The rapid changes of the upper tropospheric Tibetan anticyclone and East Asian mei-yu（＂plum rain＂） precipitation band associated with the development of the Asian monsoon system are *** principal anomalies in sea level pressure, surface wind, precipitation and sea surface temperature over southeastern China and the Philippine Sea region during El Nio events are presented. The contributions of remote El Nio-related forcing and local air–sea interaction to the occurrence of these anomalies are assessed.

关键词： atmospheric dispersion Tibetan Plateau meteorology El Nio

Preliminary Study on the Treatment Efficiency of Pasteurized Lime Thermal Alkaline Hydrolysis for Excess Activated Sludge and Reduction of Tetracycline Resistance Genes

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Journal of Renewable Materials 2023年第10期11卷 3711-3723页

作者： Maoxia Chen Qixuan Zhou Jiayue Zhang Jiaoyang Li Wei Zhang Huan Liu School of New energy Materials and Chemistry Leshan Normal UniversityLeshan614000China South Sichuan Pollution Control and resource recovery Research Center Leshan Normal UniversityLeshan614000China

Thermal alkaline hydrolysis is a common pretreatment method for the utilization of excess activated sludge(EAS).Owing to strict environment laws and need for better energy utilization,new methods were developed in this study to improve the efficiency of pretreatment *** thermal hydrolysis(TH),pasteurized thermal hydrolysis(PTH),and alkaline pasteurized thermal hydrolysis(PTH+CaO and PTH+NaOH)methods were used to treat *** method was compared and analyzed in terms of dissolution in ammonium nitrogen(NH_(4)^(+)-N)and soluble COD(SCOD)in ***,the removal of tetracycline resistance genes(TRGs)and class 1 transposon gene intI1 from EAS was *** NH_(4)^(+)-N and SCOD concentrations in EAS treated by PTH were 1.24 and 2.58 times higher than those of ***,the removal efficiency of total TRGs and intI1 between the groups was *** SCOD concentration of the PTH+NaOH group was 4.37 times higher than that of the PTH group,and the removal efficiency of total TRGs was increased by 9.52%compared with that by *** NH_(4)^(+)-N and SCOD concentrations of the PTH+CaO group could reach 85.04%and 92.14%of the PTH+NaOH group,but the removal efficiency of total TRGs by PTH+CaO was 19.78%lower than that by PTH+***,to reduce the financial cost in actual operation,lime(CaO)can be used instead of a strong alkali(NaOH),and pasteurized steam at 70℃ instead of conventional high-temperature heating to treat *** study provides a reference for the development of alkaline hydrolysis under moderate temperatures along with the removal of TRGs in EAS.

关键词： Excess activated sludge tetracycline resistance genes thermal alkaline hydrolysis lime pasteurized thermal hydrolysis

Thermo-mechanical coupling analysis of APSE using submodels and neural networks

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Journal of Rock Mechanics and Geotechnical Engineering 2013年第1期5卷 32-43页

作者： Sangki Kwon Changsoo Lee Seokwon Jeon Heui-Joo Choi energy resource Department Inha University Korea Atomic energy Research Institute energy resource Department Seoul National University

The ,Aspoe Pillar Stability Experiment （APSE） is an in situ experiment for investigating the spalling mechanism under mechanical and thermal loading conditions in a crystalline rock. In this study, the thermo-mechanical behaviors in the APSE were investigated with three models：（1） a Full model with rough meshes for calculating the influence of tunnel excavation; （2） a Submodel with fine meshes for predicting the thermo-mechanical behavior in the pillar during the borehole drilling, heating, and cool- ing phases; and （3） a Thin model for modeling the effect of slot cutting for de-stressing around the pillar. In order to import the stresses calculated from the Full model to the Submodel and to define the complex thermal boundary conditions, artificial neural networks （NNs） were utilized. From this study, it was pos- sible to conclude that the stepwise approach with the application of NNs was useful for predicting the complex response of the pillar under severe thermo-mechanical loading conditions.

关键词： Sspoe Pillar Stability Experiment (APSE)Artificial neural network (NN)SubmodelThermo-mechanical couplingSpalling

Distribution and temporal variability of the solar resource at a site in south-east Norway

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Frontiers in energy 2016年第4期10卷 375-381页

作者： Muyiwa S. ADARAMOLA Department of Ecology and Natural resource management NorwegianUniversity of Life Sciences As 1430 Norway

Globally, solar energy is expected to play a significant role in the changing face of energy economies in the near future. However, the variability of this resource has been the main barrier for solar energy development in most locations around the world. This paper investigated the distribution and variability of solar radiation using the a 10-year （2006 to 2015） data collected at Sorhs meteor- ological station located at latitude 59° 39＇ N and longitude 10° 47＇E, about 93.3 m above sea level （about 30 km from Oslo）, in south-eastern part of Norway. It is found that on annual basis, the total number of days with a global solar radiation of less than 1 kWh/（m2.d） is 120 days while the total number of days with an expected global solar radiation greater than 3 kWh/（m2.d） is 156 days （42.74%） per year. The potential energy output from a horizontally placed solar collector in these 156 days is approximately 75% of the estimated annual energy output. In addition, it is found that the inter-annual coefficient of variation of the global solar radiation is 4.28%, while that of diffuse radiation is 4.96%.

关键词： coefficient of variation global solar radiation,diffuse ratio albedo PV energy systems