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Source-specific risk assessment for cadmium in wheat and maize:Towards an enrichment model for China

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Journal of Environmental Sciences 2023年第3期125卷 723-734页

作者： Zhong Zhuang Qiqi Wang Siyu huang Andrea Giovanna NinoSavala Yanan Wan huafen Li andreas h.Schweiger andreas Fangmeier Jürgen Franzaring Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation Key Laboratory of Plant-Soil Interactions of the Ministry of EducationCollege of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China State Key Laboratory of North China Crop Improvement and Regulation Hebei Agricultural UniversityBaoding 071001China Institute of Landscape and Plant Ecology University of Hohenheim70599 StuttgartGermany

Cadmium (Cd) pollution of agricultural soil is of public concern due to its high potential toxicity and *** study aimed to reveal the risk of Cd accumulation in soil and wheat/maize systems,with a specific focus on the source-specific ecological risk,human health risk and Cd enrichment *** this we investigated more than 6100 paired soil and grain samples with 216 datasets including soil Cd contents,soil ph and grain Cd contents of 85 sites from *** results showed that mining activities,sewage irrigation,industrial activities and agricultural practices were the critical factors causing Cd accumulation in wheat and maize cultivated ***,mining activities contributed to a higher Cd accumulation risk in the southwest China and Middle Yellow River regions;sewage irrigation influenced the Cd accumulation in the North China *** addition,the investigated sites were classified into different categories by comparing their soil and grain Cd contents with the Chinese soil screening values and food safety values,*** enrichment models were developed to predict the Cd levels in wheat and maize *** results showed that the models exhibited a good performance for predicting the grain Cd contents among safe and warning sites of wheat (R2=0.61 and 0.72,respectively);while the well-fitted model for maize was prone to the overestimated sites (R2=0.77).This study will provide national viewpoints for the risk assessments and prediction of Cd accumulation in soil and wheat/maize systems.

关键词： Ecological risk Enrichment models Cadmium health risk assessment Pollution sources

Tunable structural colors on display

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Light(Science & Applications) 2022年第6期11卷 1036-1037页

作者： andreas Tittl Chair in hybrid Nanosystems Nanoinstitute MunichFaculty of PhysicsLudwig-Maximilians-Universitat MünchenKoniginstraβe 1080539 MünchenGermany

Structural coloration takes inspiration from the bright hues found in nature to control the reflection and transmission of light from artificially structured *** them with active electrical tuning heralds breakthrough... 详细信息

关键词： materials tuning breakthrough

Geoscience material structures prediction via CALYPSO methodology

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Chinese Physics B 2019年第10期28卷 38-49页

作者： andreas hermann Centre for Science at Extreme Conditions and SUPA School of Physics and Astronomy The University of Edinburgh

Many properties of planets such as their interior structure and thermal evolution depend on the high-pressure properties of their constituent materials. This paper reviews how crystal structure prediction methodology can help shed light on the transformations materials undergo at the extreme conditions inside planets. The discussion focuses on three areas:(i) the propensity of iron to form compounds with volatile elements at planetary core conditions(important to understand the chemical makeup of Earth's inner core),(ii) the chemistry of mixtures of planetary ices(relevant for the mantle regions of giant icy planets), and(iii) examples of mantle minerals. In all cases the abilities and current limitations of crystal structure prediction are discussed across a range of example studies.

关键词： crystal structure prediction core materials planetary ices hydrous minerals

Pressure induced stability: from pneumatic structures to Tensairity~

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Journal of Bionic Engineering 2004年第3期1卷 141-148页

作者： Rolf h. Luchsinger Mauro Pedretti andreas Reinhard Prospective Concepts ag Flughofstrasse 41 8152 Glattbrugg SwitzerlandAirlight Ltd. Via Croce 1 6710 Biasca Switzerland Prospective Concepts ag Flughofstrasse 41 8152 Glattbrugg Switzerland

Structural stabilization by a pressurized fluid is very common in nature, however hardly found in technology. Car tires, hot air balloons, airships and airhouses are among the few technical exceptions, which are stabilized by a compressed medium, typically air. Restricted by simple geometries and a very limited load bearing capacity these pneumatic structures could succeed only in very specialized applications. Nevertheless, prospective concepts ag has systematically investigated pneumatic structures during the last few years. As a major result, it was demonstrated that almost any shape can be made with pneumatic structures and that astonishing structures such as the pneumatic airplane Stingray can be realized even with low air pressure. On top of that, Airlight Ltd. in close collaboration with prospective concepts ag has recently developed the fundamental new structural concept Tensairity. The synergetic combination of an inflated structure with conventional structural elements such as cables and struts yields pneumatic light-weight structures with the load bearing capacity of steel girders. Thus, complex forms and high strength open up many new opportunities for pressure induced stability in technology. An overview of these recent developments is presented and the close relationship of pneumatic structures with biology is outlined.

关键词： pneumatic structures tensairity web technology aviation self-repairing membrane

Plasma optics improving plasma accelerators

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Light(Science & Applications) 2022年第9期11卷 1954-1955页

作者： andreas Dopp Ludwig-Maximilians-Universit?t Munchen GarchingGermany

Plasma accelerators driven by high-power lasers can provide high-energy electron beams on a dramatically smaller scale than conventional radio-frequency ***,the performance of these accelerators is fundamentally limited by the diffraction of the ***-generated plasma waveguides can mitigate this problem and,combined with a controlled injection method for electrons,highlight the potential of novel laser-plasma optics.

关键词： optics Plasma conventional

Achieving single-lobed far-field patterns of broad area laser diode with external cavity feedback

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Chinese Optics Letters 2003年第6期1卷 334-336页

作者：葛剑虹陈军 andreas hermerschmidt h.J.Eichler The State Key Laboratory of Modern Optical Instrumentation Zhejiang University Hangzhou 310027 Optisches Institut Technische Univeisitat Berlin StraBe des 17. Juni 135 10623 Berlin Germany

We demonstrate a technique for single transverse mode operation of high-power broad area laser diode (BAL). In the experiment, the hR mirror is used as an external cavity mirror and the grating is used as a wavelength selective component. By tiling the hR mirror and the grating, the number of transverse modes oscillating in the cavity can be limited and the spectral bandwidth of the laser diode can be reduced. A single-lobed near diffraction-limited laser beam with the beam divergence (FWhM) of 0.43°, the spectral line-width of 0.7 nm and the output power of 350 mW are obtained. With the feedback, the power density of the output laser beam is increased 6 times in comparison with the free running.

关键词： Cavity resonators Diffraction gratings high power lasers Mirrors

Automatic identification of crystal structures and interfaces via artificial-intelligence-based electron microscopy

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npj Computational Materials 2023年第1期9卷 489-499页

作者： andreas Leitherer Byung Chul Yeo Christian h.Liebscher Luca M.Ghiringhelli The NOMAD Laboratory at the Fritz-haber-Institut of the Max-Planck-Gesellschaft and IRIS-Adlershof of the humboldt-Universität zu Berlin BerlinGermany Department of Energy Resources Engineering Pukyong National UniversityBusan 48513Republic of Korea Max-Planck-Institut für Eisenforschung 40237 DüsseldorfGermany Physics Department and IRIS Adlershof Humboldt-Universität zu BerlinBerlinGermany Present address:Department of Materials Science and Engineering Friedrich-Alexander Universität Erlangen-NürnbergErlangenGermany

Characterizing crystal structures and interfaces down to the atomic level is an important step for designing advanced *** electron microscopy routinely achieves atomic resolution and is capable to resolve complex arrangements of atoms with picometer ***,we present AI-STEM,an automatic,artificial-intelligence based method,for accurately identifying key characteristics from atomic-resolution scanning transmission electron microscopy(STEM)images of polycrystalline *** method is based on a Bayesian convolutional neural network(BNN)that is trained only on simulated ***-STEM automatically and accurately identifies crystal structure,lattice orientation,and location of interface regions in synthetic and experimental *** model is trained on cubic and hexagonal crystal structures,yielding classifications and uncertainty estimates,while no explicit information on structural patterns at the interfaces is included during *** work combines principles from probabilistic modeling,deep learning,and information theory,enabling automatic analysis of experimental,atomic-resolution images.

关键词： materials crystal estimates

Numerical micro-texture optimization for lubricated contacts-A critical discussion

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Friction 2022年第11期10卷 1772-1809页

作者： Max MARIAN andreas ALMQVIST andreas ROSENKRANZ Michel FILLON Department of Mechanical and Metallurgical Engineering Pontificia Universidad Católica de ChileSantiago 690411Chile Division of Machine Elements LuleåUniversity of TechnologyLuleåSE-97187Sweden Department of Chemical Engineering Biotechnology and MaterialsFCFMUniversity of ChileSantiago 8370456Chile Institut Pprime CNRSUniversity of PoitiersPoitiers Cedex TSA 4112386073France

Despite numerous experimental and theoretical studies reported in the literature,surface micro-texturing to control friction and wear in lubricated tribo-contacts is still in the trial-and-error *** tribological behaviour and advantageous micro-texture geometries and arrangements largely depend on the contact type and the operating *** scale implementation is hampered by the complexity of numerical *** substantiates the urgent need to numerically design and optimize micro-textures for specific *** these aspects have not been covered by other review articles yet,we aim at summarizing the existing state-of–the art regarding optimization strategies for micro-textures applied in hydrodynamically and elastohydrodynamically lubricated *** analysis demonstrates the great potential of optimization strategies to further tailor micro-textures with the overall aim to reduce friction and wear,thus contributing toward an improved energy efficiency and sustainability.

关键词： micro-texturing hydrodynamics elastohydrodynamics tribo-simulation optimization

SMRs-overview,international developments,safety features and the GRS simulation chain

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Frontiers in Energy 2021年第4期15卷 793-809页

作者： andreas SChAFFRATh andreas WIELENBERG Robert KILGER Armin SEUBERT Gesellschaft für Anlagen-und Reaktorsicherheit gGmbh Boltzmannstrasse 1485748 Garching near MunichGermany

The Gesellschaft für Anlagen-und Reaktorsicherheit(GRS)gGmbh as the main technical support organization for the German Federal Government in nuclear safety has been dealing with small modular reactors(SMRs)for about one decade since SMRs are one interesting option for new builds in most countries worldwide which continue to use nuclear energy for commercial electricity *** four different SMR designs are in operation,four in construction,one is licensed,and further 12 are in a licensing *** this paper,definitions,history,and current developments of SMRs are ***,selected trends of SMR development such as factory fabrication and transport,compactness and modularity,core design,improved core cooling,exclusion of accidents,features for preventing and limiting the impact of severe accidents,economic viability,competitiveness and licensing are *** gaps of the GRS simulation chain programs with a view to applications in nuclear licensing procedures are identified and a strategy for closing these gaps is ***,selected work on the extension and improvement of the simulation chain and first generic test analyses are presented.

关键词： small modular reactors(SMRs) history recent developments safety aspects simulation chain of the Gesellschaft für Anlagen-und Reaktorsicherheit(GRS)