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In-situ investigation on real-time suspended sediment measurement techniques:Turbidimetry, acoustic attenuation,laser diffraction (LISST) and vibrating tube densimetry

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International Journal of Sediment Research 2018年第1期33卷 3-17页

作者： David Felix Ismail Albayrak Robert Michael boes Laboratory of Hydraulics Hydrology and Glaciology(VAW)ETH Zürich

Real-time measurements of Suspended Sediment mass Concentration（SSC） and Particle Size Distribution（PSD） are of prime importance for the investigation and management of fine-sediment related processes in surface water systems and hydraulic schemes. In a field study at the waterway of the hydropower plant（HPP） Fieschertal in the Swiss Alps, the real-time measurement performance of the following techniques and instruments were assessed based on measurements in the sediment seasons of the years 2013 and 2014:（1） turbidimetry,（2） single-frequency acoustic attenuation using a standard acoustic discharge measurement（ADM） installation,（3） laser diffraction（Laser In-Situ Scattering and Transmissometry, LISST）, and（4） vibrating tube densimetry using a Coriolis Flow and Density Meter（CFDM）.Reference SSCs were obtained from gravimetric analysis of 219 automatically pumped water samples.LISST additionally supplied PSD every minute. The median particle diameter, d50, was usually 15μm and increased occasionally to 100μm. The turbidimeter and the ADM underestimated the SSC when the transported particles were coarser than usual. Such temporary biases resulted from the poor correlation between d50and SSC at this study site. The SSCs from CFDM and LISST were not or less biased by PSD variations. Mainly due to angular and flaky particle shapes, SSC from LISST needed a correction by 79% on average. With the usually prevailing silt particles, an optical path length of 5 mm and no dilution, the SSC measurement range of LISST was limited to about 1.5 g/l. The CFDM allowed measuring higher SSC than the other investigated instruments（e.g. up to 13.5 g/l）. With a periodic offset correction, its relative SSC measurement uncertainty was < 20% for SSC≥ 1.5 g/I. To reliably measure a wide range of SSC with temporarily variable PSD, a combination of instruments is recommended: e.g. a standard LISST, a CFDM,and an automatic water sampler for gravimetric reference measurements.

关键词： Suspended sediment concentration Turbidity Acoustic attenuation Laser diffraction Coriolis flow and density meter Gravimetric analysis

Erosion pattern of artificial gravel deposits

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International Journal of Sediment Research 2018年第1期33卷 57-67页

作者： Fabian Friedl Volker Weitbrecht Robert M.boes Laboratory of Hydraulics Hydrology and Glaciology (VAW)ETH Zurich

Sediment replenishment with artificial gravel deposits is an option to compensate for sediment deficits in rivers and to improve their ecological conditions. Predicting and quantifying the erosion rate of an artificial gravel deposit is important to successfully perform river restoration projects. Laboratory experiments have been done to investigate the influence of various parameters on the erosion pattern of artificial gravel deposits. In the present paper the effects of deposit geometry, bulk density, grain size distribution, and hydraulic load on the erosion process are described. The temporal evolution of the deposit geometry and the corresponding mean erosion rates were studied. The mean erosion rate increases with deposit height, deposit width, and decreasing grain size. Furthermore, no significant impact of the bulk density was observed. Equations to predict the mean erosion rate are proposed. This investigation helps to determine the design frequency of gravel dumping and deposit volumes for restoration projects.

关键词： Artificial gravel deposits Bed load transport Laboratory experiments Sediment replenishment

Biodegradability of leachates from Chinese and German municipal solid waste

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第1期8卷 14-19页

作者： SELIC E. boes N. HERBELL J.D. Waste Management Engineering Department of Mechanical Engineering University of Duisburg-Essen 47057 Duisburg Germany

The quantitative and qualitative composition of Chinese municipal solid waste (MSW) differs significantly from German waste. The focus of this paper is on whether these differences also lead to dissimilar qualities of leachates during storage or landfilling. Leachates ingredients determine the appropriate treatment technique. MSW compositions of the two cities Guilin (China) and Essen (Germany), each with approx. 600 000 inhabitants, are used to simulate Chinese and German MSW types. A sequencing batch reactor (SBR) is used, combining aerobic and anaerobic reaction principles, to test the biodegradability of leachates. Leachates are tested for temperature, pH-value, redox potentials, and oxygen concentration. Chemical oxygen demand (COD) values are determined. Within 8 h, the biodegradation rates for both kinds of leachates are more than 90%. Due to the high organic content of Chinese waste, the degradation rate for Guilin MSW leachate is even higher, up to 97%. The effluent from SBR technique is suitable for direct discharge into bodies of water.

关键词：德国中国生活废物固体废物卫生填埋沥滤液生物降解能力

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A Bayesian framework for adsorption energy prediction on bimetallic alloy catalysts

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npj Computational Materials 2020年第1期6卷 195-205页

作者： Osman Mamun Kirsten T.Winther Jacob R.boes Thomas Bligaard SUNCAT Center for Interface Science and Catalysis Department of Chemical EngineeringStanford UniversityStanfordCA 94305USA SUNCAT Center for Interface Science and Catalysis SLAC National Accelerator Laboratory2575 Sand Hill RoadMenlo ParkCA 94025USA DTU Energy Department of Energy Conversion and StorageAnker Engelunds VejBuilding 3012800 Kgs.LyngbyDenmark

For high-throughput screening of materials for heterogeneous catalysis,scaling relations provides an efficient scheme to estimate the chemisorption energies of hydrogenated species.However,conditioning on a single descriptor ignores the model uncertainty and leads to suboptimal prediction of the chemisorption energy.In this article,we extend the single descriptor linear scaling relation to a multi-descriptor linear regression models to leverage the correlation between adsorption energy of any two pair of adsorbates.With a large dataset,we use Bayesian Information Criteria(BIC)as the model evidence to select the best linear regression model.Furthermore,Gaussian Process Regression(GPR)based on the meaningful convolution of physical properties of the metal-adsorbate complex can be used to predict the baseline residual of the selected model.This integrated Bayesian model selection and Gaussian process regression,dubbed as residual learning,can achieve performance comparable to standard DFT error(0.1 eV)for most adsorbate system.For sparse and small datasets,we propose an ad hoc Bayesian Model Averaging(BMA)approach to make a robust prediction.With this Bayesian framework,we significantly reduce the model uncertainty and improve the prediction accuracy.The possibilities of the framework for high-throughput catalytic materials exploration in a realistic setting is illustrated using large and small sets of both dense and sparse simulated dataset generated from a public database of bimetallic alloys available in ***.

关键词： adsorption scaling bimetallic

电化学排除钢筋混凝土结构氯盐污染的试验研究

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中国公路学报 2003年第3期16卷 44-47页

作者：干伟忠王纪跃 boes A lois 宁波高等专科学校建筑工程系浙江宁波315016 宁波市城市建设设计研究院浙江宁波315010 亚琛应用科技大学土木工程系北威州亚琛52066

针对实际混凝土结构工程,设计了用电化学方法排除氯盐污染的实验室试验;分析了电化学排除氯盐污染的影响因素;提出了实际工程中脱盐技术参数的确定方法以及无损评价方法。

关键词：桥梁工程混凝土结构试验研究氯盐污染除盐电化学

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海砂对混凝土结构中钢筋腐蚀的影响

工程力学 2001年第A2期18卷 25-29页

作者：干伟忠 boes.,A 宁波高等专科学校宁波315016

调查了海砂质量现状和海砂混凝土结构腐蚀破坏实例，通过试验证明了海砂Cl^-对混凝土结构耐久性的影响，并指出现行标准中有关海砂中Cl^-含量的阈值偏松。

关键词：海砂混凝土结构钢筋腐蚀氯离子含量

Direct characterization of a nonlinear photonic circuit’s wave function with laser light

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Light(Science & Applications) 2018年第1期7卷 1082-1086页

作者： Francesco Lenzini Alexander N Poddubny James Titchener Paul Fisher Andreas boes Sachin Kasture Ben Haylock Matteo Villa Arnan Mitchell Alexander S Solntsev Andrey A Sukhorukov Mirko Lobino Centre for Quantum Dynamics Griffith UniversityBrisbaneQLD 4111Australia Nonlinear Physics Centre Research School of Physics and EngineeringAustralian National UniversityCanberraACT 2601Australia ITMO University Saint Petersburg 197101Russia Ioffe Institute Saint Petersburg 194021Russia School of Engineering RMIT UniversityMelbourneVIC 3000Australia School of Mathematical and Physical Sciences University of Technology SydneyUltimoNSW 2007Australia Queensland Micro-and Nanotechnology Centre Griffith UniversityBrisbaneQLD 4111Australia

Integrated photonics is a leading platform for quantum technologies including nonclassical state generation1–4,demonstration of quantum computational complexity5 and secure quantum communications6.As photonic circuits grow in complexity,full quantum tomography becomes impractical,and therefore an efficient method for their characterization7,8 is essential.Here we propose and demonstrate a fast,reliable method for reconstructing the two-photon state produced by an arbitrary quadratically nonlinear optical circuit.By establishing a rigorous correspondence between the generated quantum state and classical sum-frequency generation measurements from laser light,we overcome the limitations of previous approaches for lossy multimode devices9,10.We applied this protocol to a multi-channel nonlinear waveguide network and measured a 99.28±0.31%fidelity between classical and quantum characterization.This technique enables fast and precise evaluation of nonlinear quantum photonic networks,a crucial step towards complex,largescale,device production.

关键词： quantum nonlinear characterization