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LIU TUNGSHENG'S PALAEOMAGNETIC LOESS RESEARCH IN SWITZERLAND

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第四纪研究 2009年第5期29卷 847-850页

作者： friedrich Heller Institut für Geophysik ETH-Zentrum CH-8092 Zürich

11月22日是刘东生先生的生日,在先生离开我们的一年多时间里,我们时刻在怀念他。这里我们刊登了刘先生的密友之一、瑞士的Heller教授的短文,怀念与刘先生一起研究黄土磁学的点点滴滴。本文是Heller教授为刘先生的纪念文集撰写的,但因故... 详细信息

11月22日是刘东生先生的生日,在先生离开我们的一年多时间里,我们时刻在怀念他。这里我们刊登了刘先生的密友之一、瑞士的Heller教授的短文,怀念与刘先生一起研究黄土磁学的点点滴滴。本文是Heller教授为刘先生的纪念文集撰写的,但因故未及在文集中刊出。现在本刊补登,除了表示对先生的深切怀念,也表示对Heller教授的感谢和歉意。

关键词：黄土磁学研究刘东

Acoustic and visual adaptations to predation risk: a predator affects communication in vocal female fish

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Current Zoology 2022年第2期68卷 149-157页

作者： Isabelle Pia MAIDITSCH friedrich LADICH Department of Behavioral and Cognitive Biology University of ViennaAlthanstraBe 14Vienna 1090Austria

Predation is an important ecological constraint that influences communication in *** respond to predators by adjusting their visual signaling behavior,but the responses in calling behavior in the presence of a visually detected predator are largely *** hypothesize that fish will reduce visual and acoustic signaling including sound levels and avoid escalating fights in the presence of a *** test this we investigated dyadic contests in female croaking gouramis(Trichopsis vittata,Osphronemidae)in the presence and absence of a predator(Astronotus ocella-tus,Cichlidae)in an adjoining *** behavior in *** consists of lateral(visual)displays,antiparallel circling,and production of croaking sounds and may escalate to frontal *** analyzed the number and duration of lateral display bouts,the number,duration,sound pressure level,and dominant frequency of croaking sounds as well as contest *** number and duration of lateral displays decreased significantly in predator when compared with nopredator *** number of sounds per contest dropped in parallel but no significant changes were observed in sound *** the presence of a predator,dyadic contests were decided or terminated during lateral displays and never escalated to frontal *** gouramis showed approaching behavior toward the predator between lateral *** is the first study supporting the hypothesis that predators reduce visual and acoustic signaling in a vocal *** properties,in contrast,did not *** signaling and the lack of escalating contests reduce the fish's conspicuousness and thus predation threat.

关键词： agonistic interactions antipredator behavior croaking gouramis predator inspection signaling behavior

An Introduction to Plateau's Problem

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数学进展 1990年第1期19卷 25-37页

作者： friedrich Tomi University of Heidelberg Wesf Germany

In this paper, the recent development to Plateau's problem for minimal surfaces of prescribed topological type is given briefly.

关键词：极小曲面黎曼流形 Plateau问题拓扑空间微分几何道格拉斯定理

BUILDINGS AS ACTIVE COMPONENTS FOR GRID STABILITY

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Journal of Green Building 2017年第4期12卷 21-34页

作者： friedrich Sick Ralph Füger HTW Berlin University of Applied Sciences Wilhelminenhofstr.75AD-12459 BerlinGermany

A successful energy transition depends on storage options in order to ensure power supply stability under auctuating generation of a growing share of renewable energies(RE).Battery storage is expensive and raw material intensive and therefore not suitable as a sole *** electricity may easily be converted to heat,which can be stored inexpensively for a short *** such simple Power-to-Heat or P2H solutions,lack of electric power cannot be oset by conventional heat ***,if a building or an urban quarter is heated by means of cogeneration,so-called Combined Heat and Power(CHP),or heat pumps(HP),the operation can be adjusted in such a way,that the building itself,*** massive structure,serves as heat *** generation and consumption is adjusted to the requirements of the grid(reactive power control).For the supply of a Berlin quarter,built in the 1950s and equipped with a district heating network and a CHP plant,the feasibility of the concept could be proved using dynamic building simulation as the analysis *** percent of the total heating consumption may useably be stored and extracted from the building *** absolute numbers:73 MWh/a heat can be buered corresponding to 34 MWh/a balancing *** each square meter of living area,3.7 kWh electrical balancing energy can be buered in the building’s thermal storage *** else is required than a re-programming of heating and possibly cooling *** capital investment is *** insulated and more massive structures could show a proportion of 27%of such shifted heat.

关键词： massive equipped GRID

Investigations on the Flow Field in an Unshrouded Pump Impeller Geometry

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Journal of Thermal Science 2012年第2期21卷 136-144页

作者： Sten Sieber friedrich Frhlig Saban Caglar Martin Gabi Fchgebiet Strmungsmaschinen Karlsruhe Institute of Technology Germany

Transient CFD simulations are performed to investigate the flow behaviour inside an unshrouded pump using the SAS method. Two blade designs are compared at two different tip clearances and the results are validated by measurements. The detected vortex structure is visualized by the normalized helicity, further discussed regarding its development and behaviour and finally implicated to the efficiency of the two different blade designs.

关键词： unshrouded pump tip clearance helicity

Investigation of the Flow in the Impeller Side Clearances of a Centrifugal Pump with Volute Casing

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Journal of Thermal Science 2012年第3期21卷 197-208页

作者： Bjrn-Christian Will friedrich-karl Benra Hans-Josef Dohmen Institute of Energy and Environmental Engineering TurbomachineryUniversity Duisburg-Essen

The paper is concerned with the fluid flow in the impeller side clearances of a centrifugal pump with volute *** flow conditions in these small axial gaps are of significant importance for a number of effects such as disk friction,leakage losses or hydraulic axial thrust to name but a *** the investigated single stage pump,the flow pattern in the volute turns out to be asymmetric even at design flow *** gain a detailed insight into the flow structure,numerical simulations of the complete pump including the impeller side clearances are ***,the hydraulic head and the radial pressure distributions in the impeller side clearances are measured and compared with the numerical *** configurations of the impeller,either with or without balancing holes,are ***,three different operating points,i.e.:design point,part load or overload conditions are *** addition,analytical calculations are accomplished to determine the pressure distri-butions in the impeller side *** accurate boundary conditions are available,the 1D flow models used in this paper can provide reasonable results for the radial static pressure distribution in the impeller side ***,a counter rotating wake region develops in the rear impeller side clearances in absence of balancing holes which severely affects the inflow and outflow conditions of the cavity in circumferential direction.

关键词： Cavity Rotor-Stator Cavities Side Chambers Centrifugal Pump

Use of ionic liquid in leaching process of brass wastes for copper and zinc recovery

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International Journal of Minerals,Metallurgy and Materials 2014年第2期21卷 138-143页

作者： Ayfer kilicarslan Muhlis Nezihi Saridede Srecko Stopic Bernd friedrich Department of Metallurgical and Materials Engineering (Davutpasa Campus) Yildiz Technical University Department of Process Metallurgy and Metal Recycling (IME) RWTH Aachen University

Brass ash from the industrial brass manufacturer in Turkey was leached using the solutions of ionic liquid （IL） 1-butyl-3-methyl-imi-dazolium hydrogen sulfate （[bmim]HSO4） at ambient pressure in the presence of hydrogen peroxide （H2O2） and potassium peroxymonosulfate （oxone） as the oxidants. Parameters affecting leaching efficiency, such as dissolution time, IL concentration, and oxidizing agent addition, were investigated. The results show that [bmim]HSO4 is an efficient IL for the brass ash leaching, providing the dissolution efficiencies of 99%for Zn and 24.82%for Cu at a concentration of 50vol%[bmim]HSO4 in the aqueous solution without any oxidant. However, more than 99%of zinc and 82%of copper are leached by the addition of 50vol%H2O2 to the [bmim]HSO4 solution. Nevertheless, the oxone does not show the promising oxidant behavior in leaching using [bmim]HSO4.

关键词： leaching recovery copper zinc ionic liquids oxidants

Hemispheric Specialization of the Primate Inferior Parietal Lobule

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Neuroscience Bulletin 2022年第3期38卷 334-336页

作者： Sam Vickery Simon B Eickhoff Patrick friedrich Institute of Neuroscience and Medicine Brain&Behaviour(INM-7)Research Centre Jülich52428JülichGermany Institute of Systems Neuroscience Medical FacultyHeinrich-Heine University Düsseldorf40225DüsseldorfGermany

Hemispheric asymmetries can be seen as one of the evolutionary adaptations that allowed the human brain to muster more complex cognitive processes than other *** this vein,the study published by Cheng et al.[1]presents a pivotal investigation of both the regional and connectional asymmetries within the inferior parietal lobule(IPL)in human,chimpanzee,and *** investigating 4 sub-divisions of the IPL across the three species,Cheng and colleagues showed that the macroanatomical and connectional architecture of the IPL became more asymmetric throughout the primate *** macaques show little to no structural asymmetries,chimpanzees display a more asymmetric architecture but with both leftward and rightward asymmetries in various *** contrast,the human IPL displayed the highest number of asymmetries among the three species with a clear tendency towards more *** evolutionary trend towards a more lateralized organization of the IPL may have accompanied an improved command of tool-use,stronger forelimb asymmetries,and the increasing complexity of communicative behavior.

关键词： asymmetric erior allowed

Computer modeling of high-pressure leaching process of nickel laterite by design of experiments and neural networks

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International Journal of Minerals,Metallurgy and Materials 2012年第7期19卷 584-594页

作者： Milovan Milivojevic Srecko Stopic Bernd friedrich Boban Stojanovic Dragoljub Drndarevic Technical and Business College IME Process Metallurgy and Metal Recycling RWTH Aachen University Department of Mathematics and Informatics Faculty of Science University of Kragujevac

Due to the complex chemical composition of nickel ores, the requests for the decrease of production costs, and the increase of nickel extraction in the existing depletion of high-grade sulfide ores around the world, computer modeling of nickel ore leaching process be- came a need and a challenge. In this paper, the design of experiments （DOE） theory was used to determine the optimal experimental design plan matrix based on the D optimality criterion. In the high-pressure sulfuric acid leaching （HPSAL） process for nickel laterite in ＂Rudjinci＂ ore in Serbia, the temperature, the sulfuric acid to ore ratio, the stirring speed, and the leaching time as the predictor variables, and the degree of nickel extraction as the response have been considered. To model the process, the multiple linear regression （MLR） and response surface method （RSM）, together with the two-level and four-factor full factorial central composite design （CCD） plan, were used. The proposed re- gression models have not been proven adequate. Therefore, the artificial neural network （ANN） approach with the same experimental plan was used in order to reduce operational costs, give a better modeling accuracy, and provide a more successful process optimization. The model is based on the multi-layer neural networks with the back-propagation （BP） learning algorithm and the bipolar sigmoid activation function.

关键词： nickel laterite leaching computer simulation design of experiments (DOE) response surface method (RSM) neural networks