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Separating polydisperse particles using electrostatic precipitators with wire and spiked-wire discharge electrode design

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Particuology 2018年第3期16卷 10-17页

作者： soren Sander Steffen Gawor Udo Fritsching Process Engineering Stiftung Institut ffir Werlcstofftechnik Badgasteiner Strasse 3 28359 Bremen Germany Particles and Process Engineering University of Bremen Bibliothekstrasse 1 28359 Bremen. Germany

Numerical simulations of electrostatic precipitators featuring wire and spiked electrode designs were performed to determine particle behavior and separation efficiency. The applied-voltage mechanism that alters the flow structure of particles through ionic winds and mean electric fields are revealed. Numeri- cal studies throughout the past years have shown these structures for channel and pipe configurations. However, less attention was given to field averaging for the ni,~r-product and electric field. Our study focuses on this averaging and illustrates relevant differences between multidimensional setups concern- ~ng these fields. Turbulence was modeled using the Reynolds-averaged Navier-Stokes equations with a second-order Reynolds-stress-model closure. A high three-dimensionality of the ionic wind-induced turbulence is presented. This leads to an increase in the submicron-particle precipitation rate. The results confirm the dependence of separation efficiency on particle density and permittivity, thereby showing the advantages of spiked wires compared with wire-plate setups used in electrostatic precipitators.

关键词： Electro-hydrodynamic CFD simulation Electrostatic particle precipitation Electrode design Collection efficiency

Dynamic flowsheet simulation of re-entrainment from particle layers formed inside electrostatic precipitators

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Particuology 2020年第6期18卷 41-47页

作者： soren Sander Udo Fritsching Particles and Process Engineering University of BremenBibliothekstrasse 128359 BremenGermany Process Engineering Leibniz-lnstitutfiir Werkstofforientierte Technologien-IWTBadgasteiner Strasse 328359 BremenGermany

Electrostatic precipitators clean away the particulate matter of exhaust gases in manifold industrial *** studies of particle separation in the size range of several 100 nm to 25μm is of particular interest for the prediction of precipitation efficiencies and *** typically cover the transport of particles towards walls of the ***,no model yet covers the possible re-entrainment of particles from layers formed at the walls back into the gas *** study presents the implementation of a new time-resolving model for electrostatic precipitation utilizing a re-entrainment *** data support the results of *** model uses a statistical approach based on properties of the particulate layer forming at the precipitator *** model is used for the analysis of the redispersion of particles in a laboratory-scale electrostatic precipitator(Sander,Gawor,&Fritsching,2018).Results show reduced precipitation efficiencies for particles larger than 5μm as particles have higher kinetic impact energies and lower bounding energy at the layer *** dynamics reveal a steady-state behavior of the separation for CaCO3(limestone,trademark"Ulmer WeissR")while Al2O3(trademark"Pural NFR")precipitation is affected by layer buildup at the walls increasing over several minutes.

关键词： Electrostatic precipitator Flow sheet model Redispersion and re-entrainment Gas cleaning Particle layer

Liver cirrhosis and arterial hypertension

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World Journal of Gastroenterology 2006年第5期12卷 678-685页

作者： Jens H Henriksen soren Moller Department of Clinical Physiology 239University of CopenhagenH:S Hvidovre HospitalCopenhagenDenmark

Characteristic findings in patients with cirrhosis are vasodilatation with low overall systemic vascular resistance, high arterial compliance, increased cardiac output, secondary activation of counter-regulatory systems （renin-angiotensin-aldosterone system, sympathetic nervous system, release of vasopressin）, and resistance to vasopressors. The vasodilatory state is mediated through adrenomedullin, calcitonin generelated peptide, nitric oxide, and other vasodilators, and is most pronounced in the splanchnic area. This constitutes an effective （although relative） counterbalance to increased arterial blood pressure. This review considers the alterations in systemic hemodynamics in patients with cirrhosis in relation to essential hypertension and arterial hypertension of the renal origin. Subjects with arterial hypertension （essential, secondary） may become normotensive during the development of cirrhosis, and arterial hypertension is rarely manifested in patients with cirrhosis, even in cases with renovascular disease and high circulating renin activity. There is much dispute as to the understanding of homoeostatic regulation in cirrhotic patients with manifest arterial hypertension. This most likely includes the combination of vasodilatation and vasoconstriction in parallel.

关键词： Arterial compliance Central vascular filling Chyperdynamic circulation Kidney function, Nitric oxide Blood pressure regulation Renin-angiotensin-aldosterone system Sympathetic nervous system Vasodilatation Vasoconstriction

Product portfolio map:a visual tool for supporting product variant discovery and structuring

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Advances in Manufacturing 2014年第2期2卷 179-191页

作者： soren Ulonska Torgeir Welo Faculty of Engineering Science and Technology Norwegian University of Science and TechnologyTrondheimNorway Department of Engineering Design and Materials Norwegian University of Science and TechnologyTrondheimNorway

A fundamental criterion for reusing and continuously improving knowledge in product development is ensuring that the knowledge is explicit and *** paper is based on the situation of an engineer-to-order（ETO） manufacturing company,where historically grown product variety and related knowledge are diffuse（tacit）.Consequently,several resources are used in（re）developing derivatives of previous products rather than innovating new *** establish a more competitive configure-to-order（CTO） product strategy,product knowledge needs to be revealed,systemized,and structured,and thus made ***,product-specific knowledge and product variants have been analyzed and subsequently mapped at architectural,functional,and physical levels in one unified map and tested in the form of a proof-of-concept（POC）demonstrator with the introduced SME *** result is a product portfolio map that forms a base for defining a systemized,transparent,unified product variant overview,which can be used as a basis for implementing a cross-variant product architecture and supporting knowledge-based approaches.

关键词： Knowledge-based development(KBD) Knowledge discovery Product architecture Product portfolio mapping

Host plant choice in the comma butterfly-larval choosiness may ameliorate effects of indiscriminate oviposition

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Insect Science 2014年第4期21卷 499-506页

作者： Gabriella Gamberale-Stille Lina Soderlind Niklas Janz soren Nylin Department of Zoology Stockholm University 106 92 Stockholm Sweden

In most phytophagous insects, the larval diet strongly affects future fitness and in species that do not feed on plant parts as adults, larval diet is the main source of nitrogen. In many of these insect-host plant systems, the immature larvae are considered to be fully dependent on the choice of the mothers, who, in turn, possess a highly developed host recognition system. This circumstance allows for a potential mother-offspring conflict, resulting in the female maximizing her fecundity at the expense of larval performance on suboptimal hosts. In two experiments, we aimed to investigate this relationship in the polyphagous comma butterfly, Polygonia c-album, by comparing the relative acceptance of low- and medium-ranked hosts between females and neonate larvae both within individuals between life stages, and between mothers and their offspring. The study shows a variation between females in oviposition acceptance of low-ranked hosts, and that the degree of acceptance in the mothers correlates with the probability of acceptance of the same host in the larvae. We also found a negative relationship between stages within individuals as there was a higher acceptance of lower ranked hosts in females who had abandoned said host as a larva. Notably, however, neonate larvae of the comma butterfly did not unconditionally accept to feed from the least favorable host species even when it was the only food source. Our results suggest the possibility that the disadvantages associated with a generalist oviposition strategy can be decreased by larval participation in host plant choice.

关键词： host plant choice insect-host plant interaction mobility oviposition behav-ior parent-offspring conflict specialization

In silico analysis of regulatory networks underlines the role of miR-10b-5p and its target BDNF in huntington’s disease

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Translational Neurodegeneration 2014年第1期3卷 125-129页

作者： soren Müller Molecular BioSciences University of FrankfurtMarie-Curie-Str.960439 Frankfurt a.M.Germany

Non-coding RNAs(ncRNAs)play various roles during central nervous system ***(miRNAs)are a class of ncRNAs that exert their function together with argonaute proteins by post-transcriptional gene silencing of messenger RNAs(mRNAs).Several studies provide evidence for alterations in miRNA expression in patients with neurodegenerative *** these is huntington‘s disease(HD),a dominantly inherited fatal disorder characterized by deregulation of neuronal-specific mRNAs as well as ***,next-generation sequencing(NGS)miRNA profiles from human HD and neurologically normal control brain tissues were *** consistently upregulated miRNAs affect the expression of genes involved in neuronal differentiation,neurite outgrowth,cell death and *** re-analyzed the NGS data publicly available in array express and detected nineteen additional differentially expressed ***,we connected these miRNAs to genes implicated in HD development and network analysis pointed to miRNA-mediated downregulation of twenty-two genes with roles in the pathogenesis as well as treatment of the *** silico prediction and reporter systems prove that levels of BDNF,a central node in the miRNA-mRNA regulatory network,can be post-transcriptionally controlled by upregulated miR-10b-5p and *** BDNF expression is associated with neuronal dysfunction and death in ***,the 3’UTR of CREB1 harbors a predicted binding site for these two ***1 is similarly downregulated in HD and overexpression decreased susceptibility to 3-nitropropionic-induced toxicity in a cell *** contradiction to these observations,it is presumed that miR-10b-5p upregulation in HD exerts a neuroprotective role in response to the mutation in the huntingtin ***,the function of miR-10b-5p and especially its effect on BDNF expression in HD requires further academic research.

关键词： Huntington miRNA Sequencing Post-transcriptional regulation

A laterally sensitive colloidal probe for accurately measuring nanoscale adhesion of textured surfaces

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Nano Research 2019年第2期12卷 389-396页

作者： soren Zimmermann Waldemar Klauser James Mead Shiliang Wang Han Huang Sergej Fatikow Department of Computing Science University of Oldenburg Oldenburg D-26129 Germany School of Mechanical and Mining Engineering The University of Queensland Brisbane 4072 Australia School of Physics and Electronics Central South University Changsha 410083 China

Adhesiion assessment of nanoscale contacts is a critical capability for the development of future nanoelectromechanical systems and nanobiotechnology devices. However, experimental approaches to investigate interactions on micro- and nanostructured surfaces have predominantly been restricted to capturing adhesion force in the normal direction. This provides limited information about the multidimensional nature of surface texture and related interaction mechanisms. Here the design, fabrication, and application of a unique atomic force microscope probe is presented that consists of a focused ion beam-milled cantilever decorated with a colloidal particle. The probe is specifically developed for characterizing textured surfaces with lateral force feedback. Pull-off tests that map the adhesive interaction in microscale cavities are performed to exami ne the capability of the probe. Normal and lateral adhesive forces duri ng nano scale contact are accurately obtai ned and the adhesi on en ergy of the con tact interface is thus determi ned. An in-depth un dersta nding of the effects of surface texture and the correlati on of adhesi on and fricti on is dem on strated. The proposed methodology en ables dedicated in vestigatio ns of in terfacial in teracti on on various norvplanar surfaces. It can be used for un dersta nding the complex in terplay of adhesi on, con tact, and fricti on forces at nano scale, which may facilitate significant advances in challenging research areas such as fibrillar adhesion.

关键词： nanoscale adhesion friction atomic force microscope colloidal probe lateral sensitivity

MEDES AND MINAEANS IN EGYPT-M 247:WHO,WHERE,AND WHEN?

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Journal of Ancient Civilizations 2020年第2期35卷 147-160,267页

作者： soren Lund sorensen Klaus Geus Freie Universitat Berlin

An often-quoted Minaean inscription from Baraqish(ancient Yathill)in Yemen,M 247=RES 3022,referring to"Medes"and"Minaeans"in Egypt,has been dated *** a number of reasons,we opt for a low date,proposing that the inscription refers to events during the second invasion of Egypt by the Seleucid king Antiochus IV in 168 BC in course of the Sixth Syrian *** our view,this establishes a synchronism between the ancient Mediterranean and the Old South Arabian civilisations.

关键词： invasion Egypt ancient

Large-diameter trees and deadwood correspond with belowground ectomycorrhizal fungal richness

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Ecological Processes 2023年第1期12卷 31-45页

作者： Joseph D.Birch James A.Lutz soren Struckman Jessica R.Miesel Justine Karst Department of Plant Soil and Microbial SciencesMichigan State University1066 Bogue StreetEast LansingMI 48824USA Department of Wildland Resources and the Ecology Center Utah State University5230 Old Main HillLoganUT 84322-5230USA Department of Renewable Resources University of Alberta751 General Services BuildingEdmontonAB T6G 2H1Canada

Background: Large-diameter trees have an outsized influence on aboveground forest dynamics, composition, and structure. Although their influence on aboveground processes is well studied, their role in shaping belowground fungal communities is largely unknown. We sought to test if (i) fungal community spatial structure matched aboveground forest structure;(ii) fungal functional guilds exhibited differential associations to aboveground trees, snags, and deadwood;and (iii) that large-diameter trees and snags have a larger influence on fungal community richness than smaller-diameter trees. We used MiSeq sequencing of fungal communities collected from soils in a spatially intensive survey in a portion of Cedar Breaks National Monument, Utah, USA. We used random forest models to explore the spatial structure of fungal communities as they relate to explicitly mapped trees and deadwood distributed across 1.15 ha of a 15.32-ha mapped subalpine forest. Results: We found 6,177 fungal amplicon sequence variants across 117 sequenced samples. Tree diameter, dead-wood presence, and tree species identity explained more than twice as much variation (38.7% vs. 10.4%) for ectomy-corrhizal composition and diversity than for the total or saprotrophic fungal communities. Species identity and dis-tance to the nearest large-diameter tree (≥ 40.2 cm) were better predictors of fungal richness than were the identity and distance to the nearest tree. Soil nutrients, topography, and tree species differentially influenced the composition and diversity of each fungal guild. Locally rare tree species had an outsized influence on fungal community richness. Conclusions: These results highlight that fungal guilds are differentially associated with the location, size, and species of aboveground trees. Large-diameter trees are implicated as drivers of belowground fungal diversity, particularly for ectomycorrhizal fungi.

关键词： Belowground ecology Ectomycorrhizal fungi Pinus flexilis Pinus longaeva Saprotrophic fungi Smithsonian ForestGEO Spatial dynamics Utah Forest Dynamics Plot