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Numerical Modelling of Seismic Site Effects Incorporating Non-linearity and Groundwater Level Changes

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Journal of Earth Science 2010年第6期21卷 931-940页

作者： Dominik Ehret joachim Rohn Dieter Hannich Carlos Grandas Gerhard Huber Department of Applied Geology University of Erlangen-Nuremberg Department of Applied Geology University (TH) of Karlsruhe Institute of Soil and Rock Mechanics University (TH) of Karlsruhe

In the past decades, the necessity for detailed earthquake microzonation studies was recognized worldwide. Therefore, different approaches were established and applied. Unfortunately, the majority of these approaches are not based on pre-existing field data but require extensive seismic measurements and investigations. Furthermore, these approaches incorporate non-linearity inadequately and cannot take groundwater level changes into account. For this purpose, notably numerical models are most suitable. These models require a good knowledge of the local geological conditions （especially of the uppermost unconsolidated units）, information about the geotechnical parameters of these units, and a hydrogeological model of the investigated area. Most of this information can be obtained from geotechnical investigations and surveys that have already been carried out in most densely populated areas. In a case study for Bucharest City, non-linear analyses were performed using software that is based on the visco-hypoplastic constitutive law. The results indicate that groundwater level changes have an important influence on duration and amplitude of ground response and thus should be considered for seismic microzonation studies. This approach ean be used to display site effects and to identify different microzones taking different earthquake magnitudes and groundwater levels into account.

关键词： microzonation site effect visco-hypoplasticity non-linearity Bucharest Romania.

Computer animations of color markings revealthe function of visual threat signals inNeolamprologus pulcher

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Current Zoology 2017年第1期63卷 45-54页

作者： Valentina BALZARINI Michael TABORSKY Fabienne VILLA joachim G. FROMMEN Institute of Ecology and Evolution Behavioral Ecology Division University of Bern Wohlenstrasse 50a 3032Hinterkappelen Switzerland

Visual signals, including changes in coloration and color patterns, are frequently used by animalsto convey information. During contests, body coloration and its changes can be used to assess anopponent＇s state or motivation. Communication of aggressive propensity is particularly importantin group-living animals with a stable dominance hierarchy, as the outcome of aggressive inter-actions determines the social rank of group members. Neolamprologus pulcher is a cooperativelybreeding cichlid showing frequent within-group aggression. Both sexes exhibit two vertical blackstripes on the operculum that vary naturally in shape and darkness. During frontal threat displaysthese patterns are actively exposed to the opponent, suggesting a signaling function. To investi-gate the role of operculum stripes during contests we manipulated their darkness in computeranimated pictures of the fish. We recorded the responses in behavior and stripe darkness of testsubjects to which these animated pictures were presented. Individuals with initially darker stripeswere more aggressive against the animations and showed more operculum threat *** stripes of test subjects became darker after exposure to an animation exhibiting a paleoperculum than after exposure to a dark operculum animation, highlighting the role of the dark-ness of this color pattern in opponent assessment. We conclude that （i） the black stripes on theoperculum of N. pulcherare a reliable signal of aggression and dominance, （ii） these markings playan important role in opponent assessment, and （iii） 2D computer animations are well suited to elicitbiologically meaningful short-term aggressive responses in this widely used model system ofsocial evolution.

关键词： aggression, agonistic behavior, animated pictures, cichlid fish, communication, cooperation, social, threat display.

The feasibility of coating by cooling crystallization on ibuprofen naked tablets

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Frontiers of Chemical Science and Engineering 2017年第2期11卷 211-219页

作者： Fatima Mameri Ouahiba Koutchoukali Mohamed Bouhelassa Anne Hartwig Leila Nemdili joachim Ulrich University Constantine 3 Engineering Faculty of Pharmaceutical Processes 25000 Constantine Algeria Martin Luther University Halle-Wittenberg Center of Engineering Science Thermal Process Engineering D-06099 Halle Germany

Sugar spray coating is a frequently used process in the pharmaceutical industry. However, this process presents the disadvantage to form an amorphous coating around the active ingredient. A crystalline coating formed on the surface of a tablet is highly desirable. Recently, a new process of coating by cooling crystallization has been developed and applied on bisacodyl pastilles obtained by melt crystallization. In this work, we investigated the feasibility of coating by cooling crystallization on ibuprofen ＂naked tablets＂ manufactured by compression. In the first part of this work, the solubility and the metastable zone width have been determined experimentally for the coating solution because they are essential factors for any crystallization process. In the second part, the coating process is investigated on the operating conditions that affect the surface morphology and the crystal growth rate. These experimental conditions include concentration of the coating solution, degree of sub-cooling, agitation speed, retention time, and surface properties of the naked ibuprofen tablets. The results show that naked tablet coating by cooling crystallization is feasible and can be applied in the pharmaceutical industry.

关键词： coating solution crystallization ibuprofen tablets sucrose

Efficiency of sample-based indices for spatial pattern recognition of wild pistachio(Pistacia atlantica) trees in semi-arid woodlands

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Journal of Forestry Research 2016年第3期27卷 583-594页

作者： Yousef Erfanifard joachim Saborowski Kerstin Wiegand Katrin M.Meyer Department of Natural Resources and Environment College of Agriculture Shiraz University Department of Ecosystem Modelling University of Goettingen

The efficiency of sample-based indices proposed to quantify the spatial distribution of trees is influenced by the structure of tree stands, environmental heterogeneity and degree of aggregation. We evaluated 10 commonly used distance-based and 10 density-based indices using two structurally different stands of wild pistachio trees in the Zagros woodlands, Iran, to assess the reliability of each in revealing stand structure in woodlands. All trees were completely stem-mapped in a nearly pure（40 ha） and a mixed（45 ha） stand. First, the inhomogeneous pair correlation function [g（r）] and the Clark-Evans index（CEI） were used as references to reveal the true spatial arrangement of all trees in these stands. The sampled data were then evaluated using the 20 *** was undertaken in a grid based on a square lattice using square plots（30 m 9 30 m） and nearest neighbor distances at the sample points. The g（r） and CEI statistics showed that the wild pistachio trees were aggregated in both stands, although the degree of aggregation was markedly higher in the pure stand. Three distance- and six density-based indices statistically verified that the wild pistachio trees were aggregated in both stands. The distance-based Hines and Hines statistic（ht） and the densitybased standardised Morisita（Ip）, patchiness（IP） and Cassie（CA） indices revealed aggregation of the trees in the two structurally different stands in the Zagros woodlands and the higher clumping in the pure stand, whereas the other indices were not sensitive enough.

关键词： Density-based indices Distance-basedindices Pattern recognition Wild pistachio Woodland

Flash XML applications : use AS2 and AS3 to create photo galleries, menus, and databases

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Condition-dependence and sexual ornamentation： Effects of immune challenges on a highly sexually dimorphic grasshopper

1000年

作者： joachim Bernhard Schnier

来源：畅想之星图书光盘版（南... 评论

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Insect Science 2018年第4期25卷 617-630页

作者： J. Pablo Valverde Hendrik Eggert joachim Kurtz Holger Schielzeth Department of Evolutionary Biology Bielefeld University Bielefeld Germany Institute for Evolution and Biodiversity Westfalische Wilhelms-Universitat Munster Munster Germany and 3 Department of Population Ecology Institute of Ecology Friedrich Schiller University Jena Germany Department of Population Ecology Institute of Ecology Friedrich Schiller University Jena Germany

Sexual ornaments contribute substantially to phenotypic diversity and it is particularly relevant to understand their evolution. Ornaments can assume the function of signals-of-quality that the choosy sex uses to evaluate potential mating partners. Often there are no obvious direct benefits and investment into mate choice is primarily rewarded by beneficial alleles that are inherited to the offspring. Inter-sexual communication via sexual ornaments requires honesty of the sexual signal, yet the question of what maintains honesty remains only partially solved. One solution is that honesty is maintained by trait expression being dependent on individual condition, since condition-dependent trait expression offers an effectively inexhaustible source of genetic variability. Here we test in the highly sexually dimorphic club-legged grasshopper Gomphocerus sibiricus if putative sexual ornaments, in particular the striking front-leg clubs, are more strongly affected by a lipopolysaccharide （LPS） immune challenge than putatively not sexually selected traits. Our results show overall little condition-dependent expression of morphological and song traits, with sexually selected traits exhibiting effects comparable to nonsexually selected traits （with the possible exception of stridulatory file length and syllable-to-pause ratio in advertisement songs）. Interestingly, field observations of individuals of lethally parasitized individuals suggest that a very strong environmental challenge can specifically affect the expression of the front-leg clubs. The presence of 1% of males in natural populations with missing or heavily deformed clubs plus 5% with minor club deformations furthermore indicate that there are risks associated with club development during final ecdysis and this might act as a filter against deleterious alleles.

关键词： Acrididae honest signaling Orthoptera phenotypic plasticity sexualselection

Initial nucleation of amorphous Si–B–C–N ceramics derived from polymer-precursors

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Journal of Materials Science & Technology 2019年第12期35卷 2851-2858页

作者： Ling-yan Li Hui Gu Vesna Srot Peter van Aken joachim Bill Materials Genome Institute School of Materials Science and EngineeringShanghai University99 Shangda RoadShanghai200444China Stuttgart Center for Electron Microscopy Max-Planck-lnstitute for Solid-State ResearchHeisen bergs trasse 370569StuttgartGermany Institute of Materials Science University of StuttgartHeisenbergstrasse 570569StuttgartGermany

Nucleation behavior of amorphous Si–B–C–N ceramics derived from boron-modified polyvinylsilazane procusors was systematically investigated by transmission electron microscopy(TEM) combined with spatially-resolved electron energy-loss spectroscopy(EELS) analysis. The ceramics were pyrolyzed at1000℃ followed by further annealing in N2, and SiC nano-crystallites start to emerge at 1200℃ and dominate at 1500℃. Observed by high-angle annular dark-field imaging, bright and dark clusters were revealed as universal nano-structured features in ceramic matrices before and after nucleation, and the growth of cluster size saturated before reaching 5 nm at 1400℃. EELS analysis demonstrated the gradual development of bonding structures successively into SiC, graphetic BNCxand Si3N4 phases, as well as a constant presence of unexpected oxygen in the matrices. Furthermore, EELS profiling revealed the bright SiC clusters and less bright Si3N4-like clusters at 1200–1400℃. Since the amorphous matrix has already phase separated into SiCN and carbon clusters, another phase separation of SiCN into SiC and Si3N4-like clusters might occur by annealing to accompany their nucleation and growth, albeit one crystallized and another remained in amorphous structure. Hinderance of the cluster growth and further crystallization was owing to the formation of BNCxlayers that developed between SiC and Si3N4-like clusters as well as from the excessive oxygen to form the stable SiO2.

关键词： Precursor derived ceramics Si–B–C–N Nucleation High-angle annular dark-field imaging Electron energy-loss spectroscopy

Stability of the linear chain structure for 12C in covariant density functional theory on a 3D lattice

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Science China(Physics,Mechanics & Astronomy) 2019年第11期62卷 6-13页

作者： ZhengXue Ren ShuangQuan Zhang PengWei Zhao Naoyuki Itagaki joachim AMaruhn Jie Meng State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China Yukawa Institute for Theoretical Physics Kyoto UniversityKyoto 606-8502Japan Institut fur Theoretische Physik Goethe-UniversitatMax-von-Laue-Str.160438 Frankfurt am MainGermany Department of Physics University of StellenboschStellenbosch 7600South Africa

The stability of the linear chain structure of three α clusters for 12C against the bending and fission is investigated in the cranking covariant density functional theory, in which the equation of motion is solved on a 3D lattice with the inverse Hamiltonian and the Fourier spectral methods. Starting from a twisted three α initial configuration, it is found that the linear chain structure is stable when the rotational frequency is within the range of ~2.0-~2.5 MeV. Beyond this range, the final states are not stable against fission. By examining the density distributions and the occupation of single-particle levels, however, these fissions are found to arise from the occupation of unphysical continuum with large angular momenta. To properly remove these unphysical continuum, a damping function for the cranking term is introduced. Eventually, the stable linear chain structure could survive up to the rotational frequency ~3.5 MeV, but the fission still occurs when the rotational frequency approaches ~4.0 MeV.

关键词： covariant density functional theory cranking model 3D lattice space linear chain structure alpha-cluster structure collective rotation 12C

Rationality and Social Responsibility: Essays in Honor of Robyn Mason Dawes (Modern Pioneers in Psychological Science: An Aps-Lea Series) 1 Har/DVD

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