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141.
丹麦Lynetten污水处理厂运行维护与管理 总被引:1,自引:0,他引:1
对丹麦第一大城市污水处理厂--Lynetten污水处理厂的运行、维护和日常管理进行了详细介绍.同时对该污水处理厂的能耗状况、污泥处理工艺以及污水和污泥处理费用进行了总结和分析. 相似文献
142.
Markus Plura Jens Kissing Jens Lenge Dirk Schulz Edgar Voges 《AEUE-International Journal of Electronics and Communications》2002,56(6):361-366
The standard Split-Step algorithm for calculating the signal transmission through optical fibres is significantly accelerated without relevant loss of accuracy by applying IIR filters as well as Fourier transformations for the linear operator. Depending on the system topology, high speed-up factors can be achieved by switching back and forth between time and frequency domain algorithms for the linear operator. Two different IIR filters are applied for calculating linear and parabolic dispersion. The efficiency of this algorithm in combination with an innovative step-size allocation method is evaluated. 相似文献
143.
Jens A. Hauch Pavel Schilinsky Stelios A. Choulis Richard Childers Markus Biele Christoph J. Brabec 《Solar Energy Materials & Solar Cells》2008,92(7):727-731
Flexible organic solar cells and modules based on P3ht:PCBM bulk-heterojunctions were fabricated and their lifetime was investigated under laboratory and outdoor conditions. In the laboratory cells were exposed to 1 sun illumination at 65 °C in order to accelerate the degradation. The outdoor behavior of modules was investigated at the Konarka rooftop testing setup in Lowell, MA (USA). We show that these flexible polymer solar cells have a good light stability, passing 1000 h under accelerated light soaking conditions in the laboratory, and that flexible modules survived over 1 year of outdoor exposure without performance losses. 相似文献
144.
The genomic distance problem in the Hannenhalli–Pevzner (HP) theory is the following: Given two genomes whose chromosomes are linear, calculate the minimum number of translocations, fusions, fissions and inversions that transform one genome into the other. This paper presents a new distance formula based on a simple tree structure that captures all the delicate features of this problem in a unifying way, and a linear time algorithm for computing this distance. 相似文献
145.
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147.
Personality and social relationships were assessed twice across a 4-year period in a general population sample of 489 German young adults. Two kinds of personality–relationship transaction were observed. First, mean-level change in personality toward maturity (e.g., increase in Conscientiousness and decrease in Neuroticism) was moderated by the transition to partnership but was independent of other developmental transitions. Second, individual differences in personality traits predicted social relationships much better than vice versa. Specifically, once initial correlations were controlled for, Extraversion, Shyness, Neuroticism, self-esteem, and Agreeableness predicted change in various qualities of relationships (especially with friends and colleagues), whereas only quality of relationships with preschool children predicted later Extraversion and Neuroticism. Consequences for the transactional view of personality in young adulthood are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
148.
The topic of this paper is minimum cost operative planning of pressurized water supply networks over a finite horizon and
under reliable demand forecast. Since this is a very hard problem, it is desirable to employ sophisticated mathematical algorithms,
which in turn calls for carefully designed models with suitable properties. The paper develops a nonlinear mixed integer model
and a nonlinear programming model with favorable properties for gradient-based optimization methods, based on smooth component
models for the network elements. In combination with further nonlinear programming techniques (Burgschweiger et al. in ZIB
Report ZR-05-31, Zuse Institute Berlin, 2005), practically satisfactory near-optimum solutions even for large networks can be generated in acceptable time using standard
optimization software on a PC workstation. Such an optimization system is in operation at Berliner Wasserbetriebe. 相似文献
149.
Andreas Opitz Bernhard Ecker Julia Wagner Alexander Hinderhofer Frank Schreiber Jochen Manara Jens Pflaum Wolfgang Brütting 《Organic Electronics》2009,10(7):1259-1267
Blends of organic electron and hole conductive materials are widely used for ambipolar charge carrier transport and photovoltaic cells. An obvious choice for donor–acceptor blends are organic semiconducting materials in their hydrogenated and fluorinated form, since they combine potentially suitable electronic properties with structural compatibility of the two constituents. This study focuses on the structural, optical, and electrical properties of blends using hydrogenated copper-phthalocyanine (H16CuPc) in combination with its per-fluorinated version (F16CuPc). Using X-ray scattering, scanning force microscopy and optical absorption measurements we show that mixed crystalline films are obtained by co-evaporation of the two materials. Electrical transport measurements reveal a profound reduction of the current for bipolar charge injection in mixed films. We discuss the formation of self-trapped charge transfer excitons as possible explanation for this unexpected behaviour, which impedes the usability of this system in photovoltaic cells. 相似文献
150.
Application of the Tauc-Lorentz formulation to the interband absorption of optical coating materials
Recent progress in ellipsometry instrumentation permits precise measurement and characterization of optical coating materials in the deep-UV wavelength range. Dielectric coating materials exhibit their first electronic interband transition in this spectral range. The Tauc-Lorentz model is a powerful tool with which to parameterize interband absorption above the band edge. The application of this model for the parameterization of the optical absorption of TiO2, Ta2O5, HfO2, Al2O3, and LaF3 thin-film materials is described. 相似文献