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The contribution of small leaks in a baghouse filter to dust emission in the Pm2.s range-A system approach

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Particuology 2017年第1期15卷 40-52页

作者： Oliver Kurtz jorg.meyer Gerhard Kasper Institut for mechanische Verfahrenstechnik und mechanik Karlsruhe Institute of Technology 76131 Karlsruhe Germany Freudenberg Filtration Technologies 69465 WeinheimGermany.

The contribution of leakage in a baghouse filter （defined as a short circuit between the upstream and downstream sides of the filter） to the emission of fine particles is quantified in comparison to other dust emission sources, and the influence of key operating variables on overall system response is analyzed. The study was conducted on a well-maintained pilot-scale filter unit （9 bags of 500 g/m^2 calendered polyester needle felt; total surface area 4.2 m^2） operated in Ap-controlled mode over a range of pulsing intensities, with two types of test dust （one free-flowing and the other cohesive） at inlet concentrations of 10 and 30 g/m^3. Leaks included single holes between 0.5 and 4 mm diameter, intentionally placed in either the plenum plate or one of the filter bags, as well as seamlines from bag confectioning. Emissions were sep- arated by source into a transient contribution due to dust penetration through the filter bags after each cleaning pulse, and a continuous contribution from leaks. This separation was based on a novel method of data processing that relies on time-resolved concentration measurements with a specially calibrated optical particle counter. Tiny leaks on the order of 1 mm generated the same emission level as all the bags combined, and dominated continuous emissions. The equivalent leak cross section （leakage = media emission） was about 1 ppm of the total installed filter surface, independent of upstream dust concentra- tion. Leakage through open seamlines amounted to 75% of media emissions in case of free-flowing test dust. Leakage was restricted to aerodynamic diameters less than ~5 μm （roughly the Pm2.s mass frac- tion）. For comparison, time-averaged mass penetration through conventional needle-felt media ranged from about 10^-5 to 10^-6, depending on cohesiveness of the particle material and pulse cleaning intensity, giving emission levels between about 0.02 and 0.2 mg/m^3 at the reference concentration of 10 R/m^2.

关键词： Air filtration Baghouse Pulse-cleaned filters Leaks Pm2.5 Dust emission

Brain weight predicts yawn duration across domesticated dog breeds

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Current Zoology 2020年第4期66卷 401-405页

作者： Andrew C.Gallup Lea moscatello jorg.J.m.massen Psychology Program Department of Social and Behavioral SciencesSUNY Polytechnic InstituteUticaNY13502USA Department of Psychology SUNY College at OneontaOneontaNY13820USA Animal Ecology Group Department of BiologyUtrecht UniversityPadualaan 8Utrecht CH3584The Netherlands

Previous research shows that yawning enhances intracranial circulation and regulates brain temperature. Consistent with these functional outcomes, yawn duration correlates positively with interspecies variation in brain weight across mammals, with robust relationships documented at both the taxonomic rank of class and the more restricted scale of family (e.g., Felidae). This study provides the first investigation into whether differences in brain weight within a single species, domesticated dogs Canis lupus familiaris, can predict intraspecific variation in yawn duration. measures of yawn duration were obtained from public videos available online and then paired with previously published brain and body weight data of different dog breeds. The final sample consisted of 272 yawns from 198 dogs across 23 breeds. Consistent with recent studies, we find robust correlations between yawn duration and brain weight across breeds. moreover, these correlations remain significant after controlling for differences in body weight across breeds. These findings replicate and extend upon past work in this area and provide further support that yawns evolved to serve an important and large-scale neurophysiologic function.

关键词： brain cooling brain size cortical arousal neuroanatomy

饮食纤维,糖负荷与女性非胰岛素依赖型糖尿病的危险

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美国医学会杂志（中文版） 1997年第5期16卷 213-217页

作者： jorg.,Sm JoAn.,m

目的:前瞻性评价高糖饮食、低纤维摄入与非胰岛素依赖型糖尿病危险的关系。设计:队列研究。背景:在1986年,我们对65173例已除外心血管疾病、癌症及糖尿病的年龄在40-65岁的美国妇女进行了详细的饮食问卷调查,由此计算出她们饮食中全部... 详细信息

目的:前瞻性评价高糖饮食、低纤维摄入与非胰岛素依赖型糖尿病危险的关系。设计:队列研究。背景:在1986年,我们对65173例已除外心血管疾病、癌症及糖尿病的年龄在40-65岁的美国妇女进行了详细的饮食问卷调查,由此计算出她们饮食中全部及特殊饮食纤维来源的通常摄入量、饮食糖指数及糖负荷。主要结果判定:非胰岛素依赖型糖尿病。结果:在6年的随访中,有91 5例观察对象确诊为糖尿病。经年龄、体重指数、吸烟、体育活动、糖尿病家族史、酒和谷类纤维摄入以及总能量摄入校正后,饮食糖指数与糖尿病的危险性呈正相关;最高与最低五分位比较,糖尿病的相对危险性(RR)为1.37(95%可信限[CI]1.09-1.71, P趋势=0.005);糖负荷(总饮食胰岛素需要量的指标)也与糖尿病呈正相关(RR=1.47,95% CI 1.16-1.86, P趋势=0.003);末端五分位比较,谷类纤维摄入与糖尿病的危险呈负相关(RR=0.72, 95%CI为0.58-0.90,P趋势=0. 001);与低糖负荷及高谷类纤维摄入比较,高糖负荷与低谷类纤维摄入同时存在可进一步增加糖尿病的危险性(RR=2.50,95%CI为1.14-5.51)。结论:我们的结果支持高糖负荷及低谷类纤维摄入可增加女性糖尿病危险的假设,提示为了降低糖尿病的发生率,谷类应以最低精炼程度的形式消费。

关键词：饮食纤维素糖负荷女性糖尿病 NIDDm

Colorful Insights： Advances in Imaging Drive Nove 3reakthroughs in Ca^2＋ Signaling

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molecular Plant 2015年第3期8卷 352-355页

作者： Alex Costa jorg.Kudla Dipartimento di Bioacienze Università degli Studi di Milano Via G. Celoria 26 20133 Milan Italy Istituto di Biofisica Consiglio Nazionale delle Ricerche Via G. Celoria 26 20133 Milan Italy Institut für Biologie und Biotechnologie der Pflanzen Universitat Münster Schlossplatz 4 48149 Münster Germany

In plants, Ca^2＋ signals occur in response to both environmental and developmental stimuli. These signals involve increases in [Ca^2＋] in compartments such as the cytoplasm, nucleus, and mitochondria, and can display multiple shapes ranging from sin- gle transients to repetitive Ca^2＋ oscillations. Generation and shaping of stimulus specific [Ca^2＋] signatures depends on Ca^2＋ influxes and effluxes occurring at both the plasma membrane （Pm） and membranes of the different subcellular compartments.

关键词： @@

CFD based extraction column design-Chances and challenges

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Chinese Journal of Chemical Engineering 2016年第2期24卷 259-263页

作者： mark W.Hlawitschka menwer m.Attarakilh Samer S.Alzyod Hans-jorg.Bart Chair of Separation Science and Technology POB 3049TU KaiserslauternKaiserslautern 67653Germany Center for Computational and mathematical modelling(Cm2) TU KaiserslauternKaiserslautern 67653Germany University of Jordan Department of Chemical Engineering11942 AmmanJordan

This paper shows that one-dimensional （I-D） [and three-dimensional （3-D） computational fluid dynamics （CFD）] simulations can replace the state-of-the-art usage of pseudo-homogeneous dispersion or back mixing models. This is based on standardized lab-scale cell experiments for the determination of droplet rise, breakage, coalescence and mass transfer parameters in addition to a limited number of additional mini-plant experiments with original fluids. Alternatively, the hydrodynamic parameters can also be derived using more sophisticated 3- D CFD simulations. Computational 1-D modeling served as a basis to replace pilot-plant experiments in any column geometry. The combination of 3-D CFD simulations with droplet population balance models （DPBm） increased the accuracy of the hydrodynamic simulations and gave information about the local droplet size. The high computational costs can be reduced by open source CFD codes when using a flexible mesh generation. First combined simulations using a three way coupled CFD/DPBm/mass-transfer solver pave the way for a safer design of industrial-sized columns, where no correlations are available.

关键词： CFD DPBm Column design

Assessing the sensitivity of melanoplus frigidus （Orthoptera： Acrididae） to different weather conditions＂ A modeling approach focussing on development times

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Insect Science 2008年第2期15卷 167-178页

作者： Oliver-D. Finch jorg.Loffler Roland Pape Carl-von-Ossietzky University of Oldenburg Fk V Institute of Biology and Environmental-Sciences Terrestrial Ecology D-26111 Oldenburg University of Bonn Department of Geography Meckenheimer AIlee 166 D-53115 Bonn Germany

The temperature and soil moisture conditions as well as vegetation patterns were studied to describe the habitat and to model the life cycle of melanoplusfrigidus, a true alpine grasshopper of the Scandes. In the low alpine belt of the Norwegian Scandes the species colonizes only the warmest microhabitats with maximum soil surface temperatures of 31℃. Vegetation of these habitats consists of shrub-rich heath dominated by Vaccinium myrtillus and Calluna vulgaris. Using continuously measured temperature data, the development times for four different seasons were modeled and related to field observations. The maximum delay of adult molt was estimated to amount to 3 weeks, the delay being determined by the variation in spring temperature conditions between different years. The possibilities of using m. frigidus as an indicator organism of climate change effects on alpine zoo-coenoses of the Scandes are discussed.

关键词： alpine insects climate change indicator life history thermal effective environment

Photonic integrated circuit components based on amorphous silicon-on-insulator technology

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Photonics Research 2016年第3期4卷 126-134页

作者： Timo Lipka Lennart moldenhauer jorg.muller Hoc Khiem Trieu Institute of microsystems Technology Hamburg University of Technology

We present integrated-optic building blocks and functional photonic devices based on amorphous siliconon-insulator technology. Efficient deep-etched fiber-to-chip grating couplers, low-loss single-mode photonic wire waveguides, and compact power splitters are presented. Based on the sub-μm photonic wires, 2 × 2 mach–Zehnder interferometers and add/drop microring resonators(mRRs) with low device footprints and high finesse up to 200 were realized and studied. Compact polarization rotators and splitters with ≥10 d B polarization extinction ratio were fabricated for the polarization management on-chip. The tuning and trimming capabilities of the material platform are demonstrated with efficient microheaters and a permanent device trimming method, which enabled the realization of energy-efficient photonic circuits. Wavelength multiplexers in the form of cascaded filter banks and 4 × 4 routers based on mRR switches are presented. Fabrication imperfections were analyzed and permanently corrected by an accurate laser-trimming method, thus enabling eight-channel multiplexers with record low metrics of sub-m W static power consumption and ≤1°C temperature overhead. The high quality of the functional devices, the high tuning efficiency, and the excellent trimming capabilities demonstrate the potential to realize low-cost, densely integrated, and ultralow-power 3D-stacked photonic circuits on top of CmOS microelectronics.

关键词： Photonic integrated circuit components based on amorphous silicon-on-insulator technology SOI mRR OADm

Alpine Activity Patterns of mitopus morio(Fabricius, 1779) are Induced by Variations in Temperature and Humidity at Different Scales in Central Norway

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Journal of mountain Science 2014年第3期11卷 644-655页

作者： Nils HEIN Roland PAPE Oliver-D. FINCH jorg.LOFFLER Department of C-eography University of Bonn Meckenheimer AUee 166 D-53115 Bonn Germany Achtern Nordpol 8 D-26180 Rastede Germany

Our research addresses questions about how micro-climate affects activity abundance of a common and widespread harvestman in an alpine ecosystem. Activity patterns of the Harvestman mitopus morio(Fabricius, 1779) were studied along different alpine gradients in the central Norwegian Scandes. Within a nested design, we surveyed 18 alpine habitats with pitfall traps and microclimatological equipment along oceanic-continental, two elevational, and(fine-scaled) microtopographic gradients. Sites in the oceanic region of the Scandes showed generally higher abundance of m. morio than sites in the continental region. Furthermore, along the elevational gradient, middle-alpine sites showed higher abundances than low-alpine sites. These general patterns are best explained by higher humidity in the oceanic region and in the middlealpine belt. Focusing at a finer scale, i.e. one elevational level within each region, revealed partly opposing activity patterns within relatively short distances. While in the western middle-alpine belt these patterns were best explained by humidityrelated measures but now with higher activity abundance during drier conditions, in the drier eastern middle-alpine belt heat sums rather than humidity were found to be the best explanatoryvariables for the observed patterns. Hence, our results imply a pronounced different reaction of the two populations towards climatic variables that partly even contradict the previously described general pattern. Regardless whether these differences in activity abundance in m. morio are a form of phenotypic plasticity or adaptation, our findings stress the importance of detailed autecological knowledge combined with fine-scaled climatic measurements when aiming at predictions about possible future ecosystem structures and spatiotemporal phenomena. m. morio proves to be an ideal biogeographic model organism for understanding spatio-temporal responses of alpine ecosystems under modified climatic conditions.

关键词： Climate gradients Opiliones Arctic-alpine ecosystems High mountains Scandinavia

Schottky barrier-based silicon nanowire pH sensor with live sensitivity control

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Nano Research 2014年第2期7卷 263-271页

作者： Felix m. Zorgiebel Sebastian Pregl Lotta Romhildtt jorg.Opitz W. Weber T. mikolajick Larysa Baraban Gianaurelio Cuniberti Institute for materials Science and max Bergmann Center ofBiomaterials TU Dresden 01062 Dresden Germany NamLab GmbH 01187 Dresden Germany Fraunhofer Institute IZFP Dresden 01109 Dresden Germany Institute for Semiconductors and microsystems Technology TU Dresden 01187 Dresden Germany Dresden Germany Center forAdvancing Electronics Dresden TU Dresden 01062 Dresden Germany

We demonstrate a pH sensor based on ultrasensitive nanosize Schottky junctions formed within bottom-up grown dopant-flee arrays of assembled silicon nanowires. A new measurement concept relying on a continuous gate sweep is presented, which allows the straightforward determination of the point of maximum sensitivity of the device and allows sensing experiments to be performed in the optimum regime. Integration of devices into a portable fluidic system and an electrode isolation strategy affords a stable environment and enables long time robust FET sensing measurements in a liquid environment to be carried out. Investigations of the physical and chemical sensitivity of our devices at different pH values and a comparison with theoretical limits are also discussed. We believe that such a combination of nanofabrication and engineering advances makes this Schottky barrier-powered silicon nanowire lab-on-a-chip platform suitable for efficient biodetection and even for more complex biochemical analysis.

关键词： silicon nanowires field effect transistor sub-threshold regime nanosensors pH sensor bottom-up fabrication maximum sensitivity ofsensor