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Structure modeling of terbium doped strontium-lanthanum borate

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Journal of Rare Earths 2014年第3期32卷 248-253页

作者： A.Shyichuk S.Lis G.Meinrath Department of Rare Earths Faculty of Chemistry Adam Mickiewicz University Radioactivity Environment Remediation (RER) consultants

Terbium doped strontium-lanthanum borate, Sr3La2（BO3）4：Tb （SLB）, was studied by semi-empirical computational ap- proaches using PM6 parametrization and the SPARKLE model for lanthanide（Ⅲ）（Ln（Ⅲ）） cations. The focus of interest was on structural aspects, e.g. the cell parameters and distribution of dopant ions between various sites as a function of dopant concentration. The cell linear dimensions were calculated to decrease linearly with increasing dopant molar concentration. SLB offered two sites for the dopant. Calculations predicted that one of these sites should be preferred by the Tb（Ⅲ） dopant. The optimized cell dimensions as well as the total energies differed for structures with dopant exclusively in site 1 or site 2. Computational predictions were tested against experimental results obtained for SLB synthesized by sol-gel method varying the dopant concentration. The agreement be- tween experimental and computational results was found sufficiently promising to continue the computational studies.

关键词： strontium-lanthanum borate terbium structure calculations rare earths

The effects of adsorptive materials on microbial community composition and PAH degradation at the sediment capewater interface

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international Journal of Sediment Research 2021年第4期36卷 555-565页

作者： Giovanna Pagnozzi Danny D.Reible Kayleigh Millerick Civil Environmental and Construction Engineering Texas Tech University Geosyntec consultants

Capping with layers of inert or adsorptive materials is used to control the release of polycyclic aromatic hydrocarbons(PAH) in sediment but little is known about microbial degradation processes in these materials. A rich native microbial community inhabits the sediment bed, and capping media can influence enrichment and biodegradation activity of benthic microorganisms. The aim of this study was to evaluate the effects of capping media(sand, organoclay, and powdered activated carbon [PAC]) on microbial communities under oxic conditions typical of the capewater interface, where naphthalene degradation(model PAH) is likely to be maximized. Bench scale experiments compared naphthalene concentrations, nahAc biomarker abundance, microbial community composition, and cellular attachment in systems amended with adsorptive and non-adsorptive capping materials. Results indicate that activated carbon promoted and enhanced bioactivity; PAC treatments showed high biodegradation rates,nahAc biomarker levels, and attached biological growth consistent with enrichment of the PAHdegrading genus Pseudomonae. In contrast, sand did not enhance biological activity compared to media-free systems. Naphthalene strongly influenced microbial community composition at the species level in all treatments except organoclay, which promoted biological signatures commonly associated with impeding degradation activity. Data overall suggest that adsorptive capping materials can both promote(PAC) and inhibit(organoclay) bioactivity in the surficial layer of caps, indicating that media selection is critical to the design of bioactive capping systems.

关键词： Sediments Capping Aerobic biodegradation PAH PAC

Proactive reconciliation as a tool for integrating mining and milling operations

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international Journal of Mining Science and Technology 2019年第2期29卷 239-244页

作者： Ana Carolina Chieregati Luiz Eduardo Campos Pignatari Francis Fernand Pitard Homero Delboni Jr Department of Mining and Petroleum Engineering University of Sao Paulo EDEM Engenharia Mineral Francis Pitard Sampling consultants

Historically, reconciliation has been viewed as a quality test of model estimates as well as a powerful tool for detecting and correcting problems in all stages of mine operations from resource estimation to metal production. If used correctly, reconciliation helps to better predict the life of mine(LOM), improves the adherence of production plans to the respective budget, and allows for effective control of the mining and milling processes. However, the accuracy of reconciliation results requires that all input data must be generated in accordance with the principles of sampling correctness. Furthermore, complete reconciliation systems can become extremely complex and must be carefully analyzed in order to provide realistic and helpful conclusions. Based on these concepts, this paper presents a successful proactive reconciliation system applied to a copper and gold mine in Brazil for monitoring and integrating mining and milling operations.

关键词： Reconciliation Prognostication Sampling Gold Copper

3D numerical parametric study of the influence of open-pit mining sequence on existing tunnels

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international Journal of Mining Science and Technology 2017年第3期27卷 459-466页

作者： Beyabanaki Amir Reza Gall Vojtech McMillen Jacobs Associates San Francisco CA 94105 USA Gall Zeidler consultants Ashburn VA 20147 USA

The development of open-pit mines can adversely affect and even damage existing access tunnels. To ensure the safety and serviceability of them, it is essential to know potential adverse effects of the mining sequence on existing tunnels such as displacements of the lining and additional loads on the lining. In this paper, three-dimensional numerical parametric study is performed to explore this complex interaction. This study investigates the effects of different parameters that may affect the tunnel response. These parameters are： excavation sequence method, horizontal/vertical stress ratio, slope angle, and tunnel diameter. This study shows that the mining sequence affects the stability of the tunnels. The open-pit mining activities lead to both higher axial forces in rock bolts and normal forces and bending moments in the lining. The results of the analysis also demonstrate that the mining sequence causes tunnel heave and significant tensile forces in the lining. Based on the study in this paper a better understanding of the interaction between oDen-oit minin~ seouence and tunnels will he ohtained

关键词： Three-dimensionalNumerical parametric studyExisting tunnelOpen-pit mining sequenceModeling

Modeling waves and longshore transport potential in Half Moon Bay,Grays Harbor,Washington,USA

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Acta Oceanologica Sinica 2008年第z1期27卷 46-59页

作者： PHILIP D Osborne Pacific international Engineering PLLC

A local-scale phase-resolving wave transformation model with CGWAVE is established in connection with a regional-scale coupled STWAVE-ADCIRC wave-current model for its application in the Half Moon Bay, Grays *** transformation from offshore to the harbor entrance is simulated by the STWAVE model which includes wave-current *** STWAVE results provide incident wave conditions for the local-scale CGWAVE model at its outer boundary. A simple method is developed to take into account the lateral variation of wave height in constructing the model’s wave boundary *** model was validated for three wave condition cases which yielded good agreement with field *** validated model was applied to predicting nearshore waves in the Half Moon Bay and longshore transport parameters along the wave breaking line for the existing condition and three engineering alternatives. A comparative analysis indicated that storm waves that have a combination of long period and large height are the most destructive to the crenulate shoreline in the Half Moon Bay; both 152 m jetty extension (Alt. 2) and diffraction mound enlargement (Alt. 3) would significantly reduce breaking wave height and longshore transport potential in the southwest corner of Half Moon Bay.

关键词： wave transformation model CGWAVE longshore transport crenulate shoreline

Assessment of the Energy Impact of Using Building Integrated Photovoltaic and Electrochromic Glazing in Office Building in UAE

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Engineering（科研） 2013年第1期5卷 56-61页

作者： Mohammad Katanbafnasab Bassam Abu-Hijleh Faculty of Engineering & IT The British University in Dubai Dubai-UAE KEO international consultants Abu Dhabi-UAE

The aim of this research was to explore the energy benefits and future potential of using Building Integrated Photovoltaic (BIPV) and Electrochromic Glazing (EG) within the climatic conditions of the city of Abu Dhabi. The Integrated Environmental Solutions (IES-VE) energy modeling software was used to assess the energy performance, mainly the reductions in HVAC and lighting, for different configurations and compare that to the base case scenario for south, east, west, and north facing facades. The results showed that the BIPV is most advantageous on the south fa?ade while the EC glazing performs best on the north facing windows. Moreover, the change in sensor location increased the energy savings for both cases, although the change was very marginal compared to the change of the glass properties. Using an automated light control system with dimming for both models, compared against the standard on-off lighting mechanism in the base case, the BIPV proves to have a higher total annual energy saving potential for most orientations, upto 33.5% while dynamic EC was best suited for the North orientation resulting in 7.4% reduction in the total annual energy consumption.

关键词： Renewable energy BIPV EC Glazing office building UAE computer simulation

Estimation of Aleatory Randomness by S_(a)(T_(1))-Based Intensity Measures in Fragility Analysis of Reinforced Concrete Frame Structures

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Computer Modeling in Engineering & Sciences 2022年第1期130卷 73-96页

作者： Yantai Zhang Yongan Shi Baoyin Sun ZhengWang College of Civil Engineering Nanjing Forestry UniversityNanjing210037China Arup international consultants(Shanghai)Co. Ltd.Shanghai200031China College of Civil and Transportation Engineering Hohai UniversityNanjing210098China Power China Huadong Engineering Corporation Limited(HDEC) Hangzhou311122China

Based on the multiple stripes analysis method,an investigation of the estimation of aleatory randomness by S_(a)(T_(1))-based intensity measures(IMs)in the fragility analysis is carried out for two typical low-and mediumrise reinforced concrete(RC)frame structures with 4 and 8 stories,*** sensitivity of the aleatory randomness estimated in fragility curves to various S_(a)(T_(1))-based IMs is analyzed at three damage limit states,i.e.,immediate occupancy,life safety,and collapse *** addition,the effect of characterization methods of bidirectional ground motion intensity on the record-to-record variability is *** is found that the damage limit state of the structure has an important influence on the applicability of the ground motion *** S_(a)(T_(1))-based IMs,considering the effect of softened period,can maintain lower record-to-record variability in the three limit states,and the S_(a)(T_(1))-based IMs,considering the effect of higher modes,do not show their advantage over S_(a)(T_(1)).Furthermore,the optimal multiplier C and exponentαin the dual-parameter ground motion IM are proposed to obtain a lower record-to-record variability in the fragility analysis of different damage limit ***,the improved dual-parameter ground motion IM is applied in the risk assessment of the 8-story frame structure.

关键词： RC frame structure intensity measure fragility analysis record-to-record variability softened period risk assessment

Development and application of traffic accident density estimation models using kernel density estimation

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Journal of Traffic and Transportation Engineering(English Edition) 2016年第3期3卷 262-270页

作者： Seiji Hashimoto Syuji Yoshiki Ryoko Saeki Yasuhiro Mimura Ryosuke Ando Shutaro Nanba Graduate School of Environmental and Life Science Okayama UniversityOkayama 700-0807Japan Department of Civil Engineering Fukuoka UniversityFukuoka 814-0180Japan Fukuyama consultants Co.Ltd. Futeuotea 812-0013Japan international Development consultants Co.Ltd. Aichi 460-0008Japan Toyota Transportation Research Institute Aichi 471-0024Japan

Traffic accident frequency has been decreasing in Japan in recent years. Nevertheless, many accidents still occur on residential roads. Area-wide traffic calming measures including Zone 30, which discourages traffic by setting a speed limit of 30 km/h in residential areas, have been implemented. However, no objective implementation method has been established. Development of a model for traffic accident density estimation explained by GIS data can enable the determination of dangerous areas objectively and easily, indicating where area-wide traffic calming can be implemented preferentially. This study examined the relations between traffic accidents and city characteristics, such as population, road factors, and spatial factors. A model was developed to estimate traffic accident density. Kernel density estimation （KDE） techniques were used to assess the relations efficiently. Besides, 16 models were developed by combining accident locations, accident types, and data types. By using them, the applicability of traffic accident density estimation models was examined. Results obtained using Spearman rank correlation show high coefficients between the predicted number and the actual number. The model can indicate the relative accident risk in cities. Results of this study can be used for objective determination of areas where area-wide traffic calming can be implemented preferentially, even if sufficient traffic accident data are not available.

关键词： Traffic safety Kernel density estimation (KDE) Hotspots Zone 30

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建筑师之眼

设计 2012年第1期25卷 168-169页

作者： Leeble international Art consultants

建筑师本身一定也会有崇拜的大师或者作品，在建筑师的眼中，建筑物是什么样的呢？英国的一个艺术组织international ART consultants举办了一个特别的竞赛“建筑师之眼”（ARCHITECT＇S EYE AWARDS）。

关键词：建筑师建筑物 ART