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Transformation Optics Collimating lenses for Multi-Beam Antenna Applications

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Transformation Optics Collimating Lenses for Multi-Beam Ante...

Effect of cylinder wall parameters on the final packing density of mono-disperse spheres subject to three-dimensional vibrations Author links open overlay panel

2011 4th IEEE International Symposium on Microwave,Antenna,Propagation and EMC Technologies for Wireless Communications

作者： Douglas H.werner Jeremiah P.Turpin pingjuan l.werner Department of Electrical Engineering The Pennsylvania State University University Park PA 16802USA

Transformation optics （TO） is a flexible design process for electromagnetic and optical devices with a wide range of applications including cloaking,waveguides,and antenna *** TO designs for antennas have been proposed,such as invisibility-cloaking radomes and collimating lenses;however,these designs all require inhomogeneous and anisotropic material parameters with extreme values that do not promote a practical ***,the choice of transformation is a critical part of the TO design process and determines whether the device can ultimately be *** this paper,we review two transformation designs with simple material parameters for the conversion of radiation from an embedded isotropic source into multiple highly-directive radiating beams.

关键词： anisotropic,antennas beam collimating lenses metamaterials multiple beams transformation optics

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Particuology 2024年第8期91卷 211-225页

作者： Jack R.Grogan Andrei l.Nicuşan Christopher R.K.Windows-Yule School of Chemical Engineering The University of BirminghamEdgbastonBirminghamB152TTUK

Achieving densely packed particles is desirable within the industries of ceramics,pharmaceuticals,defence and additive *** this work,we use the discrete element method(DEM)to determine the effect of wall parameters on the final packing density of mono-disperse spheres subject to 4 varying three-dimensional vibration and fill *** focus specifically on the impact of the container wall parameters on the particles'final packing *** on from the validation of the DEM simulation the particle-wall coefficient of restitution,the particle-wall coefficient of rolling friction and the particle-wall coefficient of sliding friction were varied individually and the effect on the final packing density *** relatively low particle-particle friction glass beads,the effect of these wall properties had no discernible effect on the final packing density *** on from these findings the particle-wall properties were varied at the extreme values of particle-particle coefficient of rolling friction and particle-particle coefficient of sliding *** a particle-particle coefficient of sliding friction=1,increases in particle-wall coefficient of restitution resulted in a minor increase in the final packing density of particles though this was not statistically *** a particle-particle coefficient of sliding friction=1,increases in particle-wall coefficient of rolling friction resulted in a minor decrease in the final packing density of the particles though again not to a degree where the trend can,with complete certainty,be distinguished from the random error across the ***,when the particle-particle coefficient of sliding friction=1,increases in particle-wall coefficient of sliding friction resulted in a significant decrease in the final packing density of *** decrease was attributed to the propagation of force chains throughout the *** significant decrease in final packing density with

关键词： Vibropacking Packing Densification Vibration Discrete element method Friction Wall friction Restitution

landscape of global urban environmental resistome and its association with local socioeconomic and medical status

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Science China(life Sciences) 2024年第6期67卷 1292-1301页

作者： Jun Wu Yige Hu Michael H Perlin David Danko Jun lu Manuela Oliveira Johannes werner Maria M Zambrano Maria A Sierra Olayinka O Osuolale Paweł Łabaj Nicolás Rascovan Nur Hazlin Hazrin-Chong Soojin Jang Haruo Suzuki Marina Nieto-Caballero Bharath Prithiviraj Patrick K H lee Agnieszka Chmielarczyk Anna Różańska Yongxiang Zhao lan Wang Christopher E Mason Tieliu Shi Center for Bioinformatics and Computational Biology and the Institute of Biomedical SciencesSchool of Life SciencesEast China Normal UniversityShanghai 200241China Department of Biology Program on Disease EvolutionUniversity of LouisvilleLouisville 40292USA Weill Cornell Medicine New York 10065USA The Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine New York 10065USA Department of Pulmonary Medicine Shanghai Chest HospitalShanghai Jiao Tong UniversityShanghai 200025China i3S-Instituto de Investiga玢o e Inova玢o em Saúde Universidade do PortoPorto 4050-290Portugal Ipatimup-Instituto de Patologia e Imunologia Molecular da Universidade do Porto Porto 4200-465Portugal Departamento de Biologia Faculdade de CiênciasUniversidade do PortoPorto 4050-290Portugal High Performance and Cloud Computing Group Zentrum für Datenverarbeitung(ZDV)Eberhard Karls University of TübingenW鋍hterstra遝7672074TübingenGermany Corporación Corpogen Research Center Bogotá110311Colombia Applied Environmental Metagenomics and Infectious Diseases Research(AEMIDR) Department of Biological SciencesElizade UniversityIlara-Mokin 340271Nigeria Maopolska Centre of Biotechnology Jagiellonian UniversityKraków 30-005Poland Aix-Marseille Université Mediterranean Institute of OceanologyUniversitéde ToulonCNRSIRDUM 110Marseille 83041France Department of Biological Sciences and Biotechnology Faculty of Science and TechnologyUniversiti Kebangsaan Malaysia43600 UKM BangiSelangor Institut Pasteur Korea Seoul 13488Republic of Korea Faculty of Environment and Information Studies Keio UniversityFujisawaKanagawa 252-0882Japan University of Colorado at Boulder CivilEnvironmental and Architectural DepartmentBoulder 80303USA Brooklyn College of the City University of New York Brooklyn 11210USA School of Energy and Environment City University of Hong KongHong Kong 999077China Department of Microbiology Faculty of MedicineJagiellonian UniversityKraków 30-005Poland Biological Targeting Diagnosis and The

Antimicrobial resistance(AMR)poses a critical threat to global health and development,with environmental factors—particularly in urban areas—contributing significantly to the spread of antibiotic resistance genes(ARGs).However,most research to date has been conducted at a local level,leaving significant gaps in our understanding of the global status of antibiotic resistance in urban *** address this issue,we thoroughly analyzed a total of 86,213 ARGs detected within 4,728 metagenome samples,which were collected by the Meta SUB International Consortium involving diverse urban environments in 60 cities of 27 countries,utilizing a deep-learning based *** findings demonstrated the strong geographical specificity of urban environmental resistome,and their correlation with various local socioeconomic and medical *** also identified distinctive evolutionary patterns of ARG-related biosynthetic gene clusters(BGCs)across different countries,and discovered that the urban environment represents a rich source of novel *** study provides a comprehensive overview of the global urban environmental resistome,and fills a significant gap in our knowledge of large-scale urban antibiotic resistome analysis.

关键词： urban environment metagenome antibiotic resistance resistance diversity biosynthetic gene clusters

Mixers with Microstructured Foils for Chemical Production Purposes

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化工进展 2005年第5期24卷 570-576页

作者： Bernd werner Volker Hessel Patrick lb Institut für Mikrotechnik Mainz GmbH Carl-Zeiss-Straβe 18-20D-55129 Institut für Mikrotechnik Mainz GmbHCarl-Zeiss-Straβe 18-20D-55129 MainzGermanyInstitut für Mikrotechnik Mainz GmbHCarl-Zeiss-Straβe 18-20D-55129 MainzGermany

约翰威立出版公司是世界知名的出版集团,出版、发行许多著名学术、技术期刊和书籍。《化工进展》编辑部从2005年第5期起,与新加坡约翰威立股份有限公司合作,不定期刊登其出版、发行的知名化工期刊的原版文章。欢迎读者提出宝贵意见。

关键词：化工行业 IMM 科研实力微观结构混频器

Effect of Clay Minerals on Transport of Surfactants Dispersed Multiwalled Carbon Nanotubes in Porous Media

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Acta Geologica Sinica(English Edition) 2017年第1期91卷 135-144页

作者： ZHANG Wei ZHANG Fawang HAN Zhantao lü Xiaoli lIN Daohui David werner Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological Sciences Shijiazhuang 050061 China Key laboratory of Groundwater Remediation of Hebei Province and China Geological Survey Shijiazhuang 050061 China Institute of Karst Geology Chinese Academy of Geological Sciences Guilin 541004 China Department of Environmental Science Zhejiang University Hangzhou 310028 China School of Civil Engineering and Geosciences Newcastle University NE1 7RU England U.K

Clay minerals can hinder the transport of various contaminants in soil and aquifer, but how clay minerals affect the transport of nanoparticles in aquifers has not been investigated in depth. In this paper, the transport of surfactants dispersed multi-walled carbon nanotubes（MWCNTs） in welldefined quartz sand and mixtures of quartz sand and clay minerals（kaolinite and montmorillonite） with varying ionic strengths was studied. Sodium dodecyl benzenesulfonate（SDBS） and octyl-phenolethoxylate（TX100） MWCNT suspensions can migrate through quartz sand easily, but the presence of less than 2% w/w clay minerals in quartz sand can significantly hinder the transport of MWCNT suspensions, especially at high ion strength（0.6 m M CaCl2）. The inhibition mechanism of clay minerals for surfactant-dispersed MWCNTs in porous media is the interception of MWCNTs. Kaolinite has stronger inhibition effect for MWCNTs transport than montmorillonite because more kaolinite can be retained in the quartz sand. Adsorption of surfactants by clay minerals does not affect the transport of MWCNTs significantly. This finding is important for the environmental assessment of MWCNT transport risks in soils and aquifers.

关键词： Multi-walled carbon nanotubes clay mineral surfactant colloid transport porous media

Heisenberg, uncertainty, and the scanning tunneling microscope

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Frontiers of physics 2012年第2期7卷 218-222页

作者： werner A. Hofer (1) 1. Department of Physics University of Liverpool L69 3BX Liverpool UK

We show by a statistical analysis of high-resolution scanning tunneling microscopy （STM） exper- iments, that the interpretation of the density of electron charge as a statistical quantity leads to a conflict with the Heisenberg uncertainty principle. Given the precision in these experiments we find that the uncertainty principle would be violated by close to two orders of magnitude, if this interpretation were correct. We are thus forced to conclude that the density of electron charge is a physically real, i.e., in principle precisely measurable quantity.

关键词： scanning tunneling microscope electron charge density functional theory uncertaintyrelations

The clinical rehabilitation of spine and spinal cord disorders: detection and evaluation using SPECT/CT

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Neural Regeneration Research 2014年第8期9卷 795-797页

作者： Max J. Scheyerer Clément M.l.werner Patrick Veit-Haibach Centre for Orthopaedic and Trauma Surgery University Medical CenterJosef-Stelzmann-Str.9CologneGermany Department of Surgery Division of TraumaSurgeryUniversity Hospital ZurichZurichSwitzerland Department of Medical Radiology Division of Nuclear MedicineUniversity Hospital ZurichZurichSwitzerland Department of Medical Radiology Diagnostic and Inverventional Radiolo-gyUniversity Hospital ZurichZurichSwitzerland

Spine-related disorders are caused by several factors including （1） spinal nerve/visceral nerve stimulation by perivertebral aseptic inflammation, （2） spinal nerve/visceral nerve compression by injured periverterbal soft tissue, dislocated perivertebral small joint, and proliferative/degenerative tissue and, （3） secondary damage to the spinal cord, peripheral nerve, vessels and autonomic nerve, which further stimulate nerve root sheath and surround- ing pain-carrying nerve fibers. In many cases, the source of pain cannot be detected by standard image modalities. Particularly in anatomically complex regions like the spine, SPECT/CT can be helpful for some aspects by intro- ducing a metabolical dimension to the classical way of morphology-based diagnostic. The aim of the present review was to give an overview of the adoption of SPECT/CT in a clinical spine-focused setting.

关键词： SPECT The clinical rehabilitation of spine and spinal cord disorders detection and evaluation using SPECT/CT

Three-dimensional Wentzel-Kramers-Brillouin approach for the simulation of scanning tunneling microscopy and spectroscopy

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Frontiers of physics 2014年第6期9卷 711-747页

作者： Krisztian Palotas Gabor Mandi werner A. Hofer Department of Theoretical Physics Budapest University of Technology and Economics and Condensed Matter Research Group of the Hungarian Academy of Sciences Budafoki dt 8. H-1111 Budapest Hungary Department of Theoretical Physics Budapest University of Technology and Economics Budafoki ut 8. H-1111 Budapest Hungary Surface Science Research Centre University of Liverpool L69 3BX Liverpool UK

We review the recently dew, loped three-dinmnsional （3D） atom-superposition approach for simulating scanning tunneling microscopy （STM） and spectroscopy （STS） based on ab initio electronic structure data. In the method, contributions from individual electron tunneling transitions between the tip apex atom and each of the sample surface atoms are summed up assuming tile one-dimensional （1D） Wentzel-Kramers--Brillouin （WKB） approximation in all these transitions. This 3D WKB tun- neling model is extremely suitable to simulate spin-polarized STM and STS on surfaces exhibiting a complex noncollinear magnetic structure, i.e., without a global spin quantization axis, at very low computational cost. The tip electronic structure from first principles can also be incorporated into the model, that is often assumed to be constant in energy in the vast majority of the related literature, which couht lead to a misinterpretation of experimental findings. Using this approach,we highlight some of tile electron tunneling features on a prototype frustrated hexagonal antiferro- magnetic Cr monolayer oil Ag（lll） surface. We obtain useful theoretical insights into tile simulated quantities that is expected to help the correct evaluation of experimental results. By extending the method to incorporate a simple orbital dependent electron tunneling transmission, we reinvestigate the bias voltage- and tip-dependent contrast inversion effect on the W（110） surface. STM images cal- culated using this orbital dependent model agree reasonably well with Tersoff-Hamann and Bardeen results. The computational efficiency of the model is remarkable as the k-point samplings of the surface and tip Brillouin zones do not affect the computational time, in contrast to the Bardeen method. In a certain case we obtain a relative computational time gain of 8500 compared to the Bardeen calculation, without the loss of quality. We discuss the advantages and limitations of tile 3D WKB method, and show further ways

关键词： electron tunneling STM STS WKB tunneling transmission spin polarization metal surfaces contrast inversion

leaching of rare Earth elements from an Illinois basin coal source

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Journal of Rare Earths 2019年第3期37卷 312-321页

作者： X.Yang J.werner R.Q.Honaker Department of Mining Engineering University of Kentucky

The existence of rare earth elements(REEs) in coal sources at elevated concentrations has been the focus of several studies over the past decade. However, limited research has been conducted on methods to recover and refine the REEs. This paper reports the results of a detailed study into the potential of selectively recovering REEs in an Illinois basin coal source by leaching. leaching characteristics are obtained for several segments obtained from a core sample as well as three different reject materials collected at a coal processing plant. Using a 1.2 mol/l sulfuric acid solution at 75 ℃,over 60% REE recovery is achieved from the direct floor and an inner parting material as well as the coal-rich core segments that are pretreated by low-temperature plasma oxidation to obtain access to the microdispersed mineral matter. In the leachable parting material, fluorapatite is detected by XRD analysis,which is one of the more soluble phosphate minerals with a documented association with REEs. For the three plant reject samples, the leaching recovery values obtained for the heavy REEs are higher than those obtained for the light REEs under the standard leaching conditions and when 0.1 mol/l(NH_4)_2SO_4 was used to extract REEs by an ion exchange mechanism. Thermal activation by roasting or chemical activation by pretreatment using 8 mol/l NaOH solution increases the total REE recovery with significantly higher gains obtained for the light REEs. leaching kinetics are relatively fast within the first 2 h and then slow to provide relatively low overall recovery values under the standard test conditions for the coarse and fine reject samples. However, significantly higher recovery values are realized when treating mixed-phase(middling) particles existing within the coarse reject material.

关键词： leaching Coal Thermal activation Chemical activation Rare earth elements