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Mechanical proper ties of lateral transition metal dichalcogenide heterostructures

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Frontiers of physics 2021年第1期16卷 23-29页

作者： Sadegh Imani Yengejeh william Wen Yun Wang Centre for Clean Environment and Energy School of Environment and ScienceGriffith UniversityGold Coast CampusSouthport 4222Australia

Transition metal dichalcogenide(TMD)monolayers attract great attention due to their specific structural,electronic and mechanical *** formation of their lateral heterostructures allows a new degree of flexibility in engineering electronic and optoelectronic ***,the mechanical properties of the lateral heterostructures are rarely *** this study,a comparative investigation on the mechanical characteristics of 1H,IT'and 1H/1T'heterostructure phases of different TMD monolayers including molybdenum disulfide(M0S_(2))molybdenum diselenide(MoSe_(2)),Tungsten disulfide(WS_(2)),and Tungsten diselenide(WSe_(2))was conducted by means of density functional theory(DFT)*** results indicate that the impact of the lateral heterostructures has a relatively weak mechanical strength for all the TMD *** significant correlation bet ween the mechanical properties of the TMD monolayers and their structural phases can be used to tune their stiffness of the *** findings,therefore,suggest a novel strategy to manipulate the mechanical characteristics of TMDs by engineering their structural phases for their practical applications.

关键词： transition metal dichalcogenide lateral heterostructures mechanical properties in-plane stiffness tensor density functional theory

Mercury transportation in soil via using gypsum from flue gas desulfurization unit in coal-fired power plant

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Journal of Environmental Sciences 2013年第9期25卷 1858-1864页

作者： Kelin Wang william Orndorff Yan Cao Weiping Pan Institute for Combustion Science and Environmental Technology Western Kentucky University

The mercury flux in soils was investigated, which were amended by gypsums from flue gas desulphurization （FGD） units of coal- fired power plants. Studies have been carried out in confined greenhouses using FGD gypsum treated soils. Major research focus is uptakes of mercury by plants, and emission of mercury into the atmosphere under varying application rates of FGD gypsum, simulating rainfall irrigations, soils, and plants types. Higher FGD gypsum application rates generally led to higher mercury concentrations in the soils, the increased mercury emissions into the atmosphere, and the increased mercury contents in plants （especially in roots and leaves）. Soil properties and plant species can play important roles in mercury transports. Some plants, such as tall fescue, were able to prevent mercury from atmospheric emission and infiltration in the soil. Mercury concentration in the stem of plants was found to be increased and then leveled off upon increasing FGD gypsum application. However, mercury in roots and leaves was generally increased upon increasing FGD gypsum application rates. Some mercury was likely absorbed by leaves of plants from emitted mercury in the atmosphere.

关键词： flue gas desulphurization gypsums soils mercury emissions mercury uptakes mercury infiltration greenhouse tests

Oil spill detection on the ocean surface using hybrid polarimetric SAR imagery

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Science China Earth Sciences 2016年第2期59卷 249-257页

作者： LI HaiYan PERRIE william ZHOU YuanZe HE YiJun Key Laboratory of Computational Geodynamics Chinese Academy of Sciences College of Earth Sciences University of Chinese Academy of Sciences Fisheries and Oceans Canada Bedford Institute of Oceanography School of Marine Sciences Nanjing University of Information Science and Technology

Hybrid-polarimetric SAR(synthetic aperture radar) is a new SAR mode, with relatively simple architecture, low cost, and wide swath, which will be carried by several Earth-observing systems from now to the near future. Here, we show how the second Stokes parameter of hybrid-polarimetric SAR can be employed to detect oil on the ocean surface using the classic well-known Otsu threshold methodology, in relation to contributions from different polarizations and dampening effects on backscatter intensity, neglecting the specific scattering mechanisms and oil types for an oil-covered surface. The detection methodology is demonstrated to be reliable in three example cases: oil-on-water experiments conducted by the Norwegian Clean Seas Association, natural oil seeps from the Gulf of Mexico, and observations from the Deep Water Horizon oil spill disaster in 2010.

关键词： Oil spill detection Hybrid polarization Compact polarimetric SAR Stokes parameters Otsu threshold

Whole-mine subsidence over tabular deposits and related seismicity

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International Journal of Mining Science and Technology 2017年第1期27卷 171-177页

作者： Pariseau william G. McCarterr Michael K. Department of Mining Engineering University of UtahSalt Lake CityUTUSA

The challenge of estimating mine-wide subsidence and linkages to seismicity over tabular deposits is addressed by a special finite element technique(dual node–dual mesh). Subsidence and mine-induced seismicity begins near the face when caving occurs and propagates to the surface as extraction reaches a critical extent. Thus, the challenge is to obtain details at the face at the meter scale and also at the surface over the whole mine at the kilometer scale. Interactions between old and new sections of a mine are automatically taken into account with this technique. The finite element method is well established technology based on fundamentals of physical laws, kinematics and material laws. With this technique, no empirical ‘‘scaling" or fitting computer output by input data ‘‘adjustment" to mine measurements is necessary. Capability is demonstrated for doing practical whole-mine subsidence analysis from first principles. Mine-induced seismicity is shown to correlate well with face advance and element failure.

关键词： Whole mine subsidence Multi-scale Finite element analysis Mine induced seismicity

Numerical study of electromagnetic scattering from one-dimensional nonlinear fractal sea surface

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Chinese Physics B 2010年第2期19卷 234-239页

作者：谢涛何超 william Perrie 旷海兰邹光辉陈伟 School of Information Engineering Wuhan University of Technology Bedford Institute of Oceanography B2Y 4A2DartmouthNSCanada

In recent years, linear fractal sea surface models have been developed for the sea surface in order to establish an electromagnetic backscattering model. Unfortunately, the sea surface is always nonlinear, particularly at high sea states. We present a nonlinear fractal sea surface model and derive an electromagnetic backscattering model. Using this model, we numerically calculate the normalized radar cross section （NRCS） of a nonlinear sea surface. Comparing the averaged NRCS between linear and nonlinear fractal models, we show that the NRCS of a linear fractal sea surface underestimates the NRCS of the real sea surface, especially for sea states with high fractal dimensions, and for dominant ocean surface gravity waves that are either very short or extremely long.

关键词： fractals nonlinearities sea surface electromagnetic scattering

Global warming potential associated with Irish milk powder production

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Frontiers of Environmental Science & Engineering 2017年第3期11卷 123-130页

作者： william Finnegan Jamie Goggins Aksana Chyzheuskaya Xinmin Zhan College of Engineering and nformatics National University of Ireland Galway H91 HX31 Galway Ireland Ryan Institute for Environmental Marine and Energy Research National University of Ireland Galway H91 DK59 Galway Ireland Centre for Marine and Renewable Energy (MaREI) H91 HX31 Galway Ireland Socio-Economic Marine Research Unit (SEMRU) National University of Ireland Galway H91 WN80 Galway Ireland

Climate change is an ever growing issue and a major concem worldwide. Both producers and processors need to address the issue now by reducing, their carbon footprint. Additionally, if Ireland is to meet their climate and energy targets, as outlined in Food Harvest 2020, which outlines a range ot objectives for the Irish agricultural sector, the efficient use of resources and fuels within the industry will need to be increased. In Ireland, agriculture accounts for 29.2% of the total greenhouse gas powder, is examined in order to estimate the global warming potential （GWP） associated with its manufacture using life cycle assessment. A cradle-to-processing factory gate analysis, which includes raw milk production, raw milk transportation to the processmg tactory, its processing into eacla product and product packaging, is assessed in this study using data collected circa 2013. The factories surveyed processed approximately 24% of the total raw milk processed in the Republic of Ireland in 2013, which was 5.83 billion liter. The average total GWP associated with the manufacture of milk powder is 9.731 kg CO2eq·kg^-1 milk powder, which has a standard deviation of 2.26 kg CO2eq·kg^-1 milk powder, for the life cycle stages analyzed in this study. The most significant contributor to GWP is raw milk production （84%）, followed by dairy processing （14%）, with the remainder of the life cycle stages contributing approximately 2%.

关键词： Dairy Global wanning potential Ireland Life cycle assessment Milk powder Milk production

Arsenic dynamics in the rhizosphere and its sequestration on rice roots as affected by root oxidation

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Journal of Environmental Sciences 2014年第4期26卷 892-899页

作者： Weisong Pan Chuan Wu Shengguo Xue william Hartley Institute of Environmental Engineering School of Metallurgical Science and Engineering Central South University College of Bioscience and Biotechnology Hunan Agricultural University Crop and Environment Sciences Department Harper Adams University

A pot experiment was conducted to investigate the effects of root oxidation on arsenic （As） dynamics in the rhizosphere and As sequestration on rice roots. There were significant differences （P 〈 0.05） in pH values between rhizosphere and non-rhizosphere soils, with pH 5.68-6.16 in the rhizosphere and 6.30-6.37 in non-rhizosphere soils as well as differences in redox potentials （P 〈 0.05）. Percentage arsenite was lower （4%-16%） in rhizosphere soil solutions from rice genotypes with higher radial oxygen loss （ROL） compared with genotypes with lower ROL （P 〈 0.05）. Arsenic concentrations in iron plaque and rice straw were significantly negatively correlated （R = -0.60, P 〈 0.05）. Genotypes with higher ROL （TD71 and Yinjingmanzhau） had significantly （P 〈 0.001） lower total As in rice grains （1.35 and 0.96 mg/kg, respectively） compared with genotypes with lower ROL （IAPAR9, 1.68 mg/kg; Nanyangzhan 2.24 mg/kg） in the As treatment, as well as lower inorganic As （P 〈 0.05）. The present study showed that genotypes with higher ROL could oxidize more arsenite in rhizosphere soils, and induce more Fe plaque formation, which subsequently sequestered more As. This reduced As uptake in aboveground plant tissues and also reduced inorganic As accumulation in rice grains. The study has contributed to further understanding the mechanisms whereby ROL influences As uptake and accumulation in rice.

关键词： arsenic iron plaque rhizosphere radial oxygen loss rice

Granular activated carbons from palm nut shells for gold di-cyanide adsorption

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International Journal of Minerals,Metallurgy and Materials 2013年第2期20卷 172-179页

作者： william K.Buah Paul T.williams Energy Research Institute The University of LeedsLeeds LS2 9JTUnited Kingdom

Granular activated carbons were produced from palm nut shells by physical activation with steam. The proximate analysis of palm nut shells was investigated by thermogravimetric analysis, and the adsorption capacity of the activated carbons, produced as a result of shell pyrolysis at 600℃ followed by steam activation at 900℃ in varying activation times, was evaluated using nitrogen adsorption at 77 K. Applicability of the activated carbons for gold dicyanide adsorption was also investigated. Increasing the activation hold time with the attendant increase in the degree of carbon burn-off results in a progressive increase in the surface area of the activated carbons, reaching a value of 903.1 m2/g after activation for 6 h. The volumes of total pores, mieropores, and mesopores in the activated carbons also increase progressively with the increasing degree of carbon burn-off, resulting from increasing the activation hold time. The gold di-cyanide adsorption of the activated carbons increases with the rise of pore volume of the activated carbons. The gold di-cyanide adsorption of palm nut shell activated carbon obtained after 6-h activation at 900℃ is superior to that of a commercial activated carbon used for gold di-cyanide adsorption.

关键词： activated carbon adsorption gold cyanides processing pyrolysis

Status of semen analysis comment on “A survey on the status of semen analysis in 118 laboratories in China” by Jin-Chun Lu et al. in Asian Journal of Andrology

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Asian Journal of Andrology 2010年第1期12卷 115-117页

作者： Hugh william Gordon Baker Department of Obstetrics and Gynaecology University of Melbourne and Melbourne IVF Reproductive Services TheRoyal Women＇s Hospital Parkville 3052 Victoria Australia

The paper by Lu et al. [1] ＂A survey on the status of semen analysis in 118 laboratories in China＂ provides a major review of the current methods of semen analysis in China's Mainland. It involved a 36-item questionnaire completed by technicians in 118 of a possible 145 potential semen laboratories. Recruitment for the study was via contacts developed at Chinese Andrology meetings and training sessions between 2005 and 2007. It is not stated how comprehensive this strategy would be for accessing all semen laboratories in China. About half the participating laboratories were in general hospitals and the others in hospitals with academic affiliations or family planning institutes.

关键词： no english key word