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排序方式: 共有1188条查询结果,搜索用时 390 毫秒
91.
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
92.
Carsten Ochsen 《Papers in Regional Science》2021,100(4):1025-1053
Since the early 1970s, it was argued that shifts from relatively smaller to larger youth cohorts in the labor force raise the unemployment rate. In contrast, using US state-level data, two studies come to a contrary conclusion. I provide a theoretical framework for local labor markets that considers age cohort differences in labor market characteristics. Using a spatial panel data model and US county-level data (2000–2014), the estimates provide strong evidence that aging of the working-age population reduces overall unemployment by almost 1 percentage point. Long-run effects that consider local feedbacks are even larger. 相似文献
93.
Jekaterina Hermane Ilona Bułyszko Dr. Simone Eichner Dr. Florenz Sasse Wera Collisi Prof. Dr. Antti Poso Emilia Schax Dr. Johanna‐Gabriela Walter Prof. Dr. Thomas Scheper Dr. Klaus Kock Prof. Dr. Christian Herrmann Dr. Pooyan Aliuos Prof. Dr. Günter Reuter Priv.‐Doz. Dr. Carsten Zeilinger Prof. Dr. Andreas Kirschning 《Chembiochem : a European journal of chemical biology》2015,16(2):302-311
Streptomyces hygroscopicus is a natural producer of geldanamycin. Mutasynthetic supplementation of an AHBA‐blocked mutant with all possible monofluoro 3‐aminobenzoic acids provided new fluorogeldanamycins. These showed strong antiproliferative activity and inhibitory effects on human heat shock protein Hsp90. Binding to Hsp90 in the low nanomolar range was determined from molecular modelling, AFM analysis and by calorimetric studies. 相似文献
94.
Hannah Baars Julien Engel Lucas Mertens Daniela Meister Carsten Bolm 《Advanced Synthesis \u0026amp; Catalysis》2016,358(14):2293-2299
Carbamoyl fluorides are formed in reactions of hydroxylamines with difluorocarbene generated from sodium bromodifluoroacetate as readily available and non‐toxic carbene precursor. The process shows a high functional group tolerance, and the reaction path has been rationalized by computational calculations.
95.
Gtz Hüsken Stephan Pirskawetz Dietmar Meinel Veronika Babski Hans‐Carsten Kühne 《Bautechnik》2016,93(10):711-716
Methods for analyzing the fracture behavior of high‐strength steel fiber‐reinforced concretes High‐strength and ultra‐high strength fiber‐reinforced concretes are most suitable for applications with extreme mechanical loads. These extreme conditions require a ductile behavior under tensile loading, which is obtained solely by the addition of steel fibers and their working mechanism. Profound know ledge on the working mechanism of the steel fibers is necessary for optimizing this material. Usually, this knowledge is obtained by means of classical measuring techniques of destructive tests. Adopting measuring techniques from non‐destructive material testing helps to analyze and to identify the different stages of the fracture mechanism of high‐strength and ultra‐high strength fiber‐reinforced concretes in detail. The application of different non‐destructive measuring techniques is shown exemplary on tensile tests conducted on an ultra‐high strength fiber‐reinforced concrete and its applicability for analyzing the fracture behavior is discussed. The main focus is on the characterization of the relevant failure modes under tensile loading by the different measuring techniques and the comparison with classical measuring techniques (e. g. extensometer). The tensile tests have been analyzed by optical deformation measurements using digital image correlation (DIC), acoustic emission analysis (AE), and 3D computed tomography (CT). 相似文献
96.
Yanjun Xie Callum A. S. Hill Zefang Xiao Zaihan Jalaludin Holger Militz Carsten Mai 《应用聚合物科学杂志》2010,117(3):1674-1682
The modifying effects of Scots pine (Pinus sylvestris L.) wood with the crosslinking agent glutaraldehyde (GA) on the water vapor sorption kinetics were studied by curve fitting the experimental isotherm sorption data obtained using a Dynamic Vapor Sorption apparatus using the parallel exponential kinetics model (PEK model) and the Hailwood–Horrobin model (H–H model) for the isotherm. Both the H–H model and the PEK model provided good fits to the experimental data. Modification of wood with GA reduced both the time to equilibrium and the equilibrium moisture content (EMC). According to the PEK and H–H models, the reduction in EMC was mainly due to the decrease of moisture content (MC) associated with the slow sorption processes and polylayer water. The fast sorption processes and monolayer water were little affected by GA modification. Compared to the untreated control, the estimated total water absorbed by wood treated to a WPG of 20.9% at 100% RH decreased by 52.2%, by extrapolating the fitted curves derived from the H–H model. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
97.
Low temperature sintering of barium titanate ceramics assisted by addition of lithium fluoride-containing sintering additives 总被引:1,自引:0,他引:1
Hamid Naghib-zadeh Carsten Glitzky Ilona Drfel Torsten Rabe 《Journal of the European Ceramic Society》2010,30(1):81-86
By addition of LiF-containing sintering additives to commercial BaTiO3 powder, more than 98% of the theoretical density was reached at a sintering temperature of 900 °C both on powder compacts and laminates. Dielectric measurements were performed on ceramic samples in the temperature and frequency ranges from −20 °C to 125 °C and from 103 to 106 Hz, respectively. High relative permittivity (r 3160) and low dielectric loss (tan δ 0.014) were measured for tapes of the favoured material. The breakdown strength for tapes with a thickness of about 80 μm is 30 kV/mm. The microprobe analysis showed, that no interfacial reaction between the dielectric layer and the Ag-electrode had occurred.The newly developed barium titanate ceramics completely densifying at 900 °C turned out to be promising for integration of buried capacitors in LTCC multilayers. 相似文献
98.
Julien Bonnamour María Piedrafita Carsten Bolm 《Advanced Synthesis \u0026amp; Catalysis》2010,352(10):1577-1581
Intramolecular C O bond forming reactions of aryl 2‐bromobenzyl ketones lead to benzo[b]furans. The cyclizations can be catalyzed by 10 mol% of iron trichloride (of 98% or of 99.995% purity) or sub‐mol% quantities of copper(II) chloride (of 99.995% purity). 相似文献
99.
Hans‐Jörg Breyholz Dr. Stefan Wagner Dr. Andreas Faust Dr. Burkhard Riemann Prof. Dr. Carsten Höltke Dr. Sven Hermann Dr. Otmar Schober Prof. Dr. Michael Schäfers Prof. Dr. Klaus Kopka Priv.‐Doz. Dr. 《ChemMedChem》2010,5(5):777-789
Matrix metalloproteinases (MMPs) are zinc‐ and calcium‐dependent endopeptidases. Representing a subfamily of the metzincin superfamily, MMPs are involved in the proteolytic degradation of components of the extracellular matrix. Unregulated MMP expression, MMP dysregulation and locally increased MMP activity are common features of various diseases, such as cancer, atherosclerosis, stroke, arthritis, and others. Therefore, activated MMPs are suitable biological targets for the specific visualization of such pathologies, in particular by using radiolabeled MMP inhibitors (MMPIs). The aim of this work was to develop a radiofluorinated molecular probe for noninvasive in vivo imaging for the detection of up‐regulated levels of activated MMPs in the living organism. Fluorinated MMPIs ( 26 , 31 and 38 ) based on the pyrimidine‐2,4,6‐trione lead structure RO 28‐2653 ( 1 ) were synthesized, and their MMP inhibition potency was evaluated in vitro. The radiosynthesis and the in vivo biodistribution of the first 18F‐labeled prototype, MMP‐targeted tracer [18F] 26 , suitable for molecular imaging by means of positron emission tomography (PET) were realized. 相似文献
100.
Kristin Engels Dr. Carsten Beyer Dr. Maria L. Suárez Fernández Frank Bender Michael Gaßel Dr. Gottfried Unden Prof. Dr. Richard J. Marhöfer Dr. Jeremy C. Mottram Prof. Dr. Paul M. Selzer Prof. Dr. 《ChemMedChem》2010,5(8):1259-1271
Apicomplexan parasites encompass several human‐ and animal‐pathogenic protozoans such as Plasmodium falciparum, Toxoplasma gondii, and Eimeria tenella. E. tenella causes coccidiosis, a disease that afflicts chickens, leading to tremendous economic losses to the global poultry industry. The considerable increase in drug resistance makes it necessary to develop new therapeutic strategies against this parasite. Cyclin‐dependent kinases (CDKs) are key molecules in cell‐cycle regulation and are therefore prominent target proteins in parasitic diseases. Bioinformatics analysis revealed four potential CDK‐like proteins, of which one—E. tenella CDK‐related kinase 2 (EtCRK2)—has already been characterized by gene cloning and expression. 1 By using the CDK‐specific inhibitor flavopiridol in EtCRK2 enzyme assays and schizont maturation assays (SMA), we could chemically validate CDK‐like proteins as potential drug targets. An X‐ray crystal structure of human CDK2 (HsCDK2) served as a template to build protein models of EtCRK2 by comparative homology modeling. Structural differences in the ATP binding site between EtCRK2 and HsCDK2, as well as chicken CDK3, were addressed for the optimization of selective ATP‐competitive inhibitors. Virtual screening and “wet‐bench” high‐throughput screening campaigns on large compound libraries resulted in an initial set of hit compounds. These compounds were further analyzed and characterized, leading to a set of four promising lead compounds for development as EtCRK2 inhibitors. 相似文献