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排序方式: 共有1765条查询结果,搜索用时 9 毫秒
71.
Robert C. Pullar Yong Zhang Lifeng Chen Shoufeng Yang Julian R.G. Evans Peter Kr. Petrov Andrei N. Salak Dmitry A. Kiselev Andrei L. Kholkin Victor M. Ferreira Neil McN. Alford 《Journal of the European Ceramic Society》2007,27(16):4437-4443
Applying combinatorial methods to materials science offers the opportunity to accelerate the discovery of more efficient dielectric ceramics. High-throughput methods have the potential to investigate the effects of a wide range of dopants on the dielectric properties, and to optimise existing systems, encouraging the short innovation cycles that the communications technology industry requires. The London University Search Instrument (LUSI) is a fully automated, high-throughput combinatorial robot that has the potential capability to produce large numbers of sintered bulk ceramic samples with varying composition in 1 day, as combinatorial libraries on alumina substrates. Ba1−xSrxTiO3 (BST) libraries were produced by LUSI as a proof-of-principle, with x = 0–1 in steps of 0.1, and fired to 1350 and 1400 °C for 1 h. Part I of this paper described the manufacture and physical characterisation of BST libraries, showing a regular change in composition with x across the libraries. In this second part, the dielectric properties of BST libraries produced by LUSI are assessed at frequencies between 100 Hz and 1 MHz, and at temperatures between 150 and 500 K. Local piezoelectric properties were also characterised by scanning probe microscope (SPM). All measurements showed evidence of a clear functional gradient varying with x across the library, with measured r corresponding to expected values for BST. 相似文献
72.
Performance of a bioreactor with submerged membranes for aerobic treatment of municipal waste water 总被引:23,自引:0,他引:23
Aerobic treatment of municipal waste water in a membrane bioreactor was studied for 535 d. Apart from sampling, sludge was retained completely by a submerged hollow fibre membrane with a pore-size of 0.2 microm. The pilot plant comprised an anoxic zone to enable denitrification. The maximum liquid hold-up of the plant was 3.9 m3. In this study the reactor performance and the stability of the process and the membrane capacity were investigated. A stable flux of 181 m(-2)h(-1) could be realised with a mean transmembrane pressure difference of 0.3bar with air-bubbling and backflushing the membrane and cleaning it in place every two months for one or two hours. For about 140d, a flux of 271 m(-2)h(-1) was achieved, but cleaning became necessary more often. The hydraulic retention time (HRT) varied between 10.4 and 15.6h. Accordingly the volumetric loading rate was between 1.1 and 1.7kg CODm(-3)d(-1). No inoculum was used. The mixed liquor suspended solids (MLSS) concentration gradually increased to 18-20g MLSSl(-1). The feed to microorganism (F/M) ratio varied according to the operation conditions but decreased against a value of 0.07 kg COD kg(-1) MLSSd(-1). Treatment performance was very stable and on a high level. The COD was reduced by 95%. Nitrification was complete and up to 82% of the total nitrogen could be denitrified. 相似文献
73.
V. Hable C. Greubel A. Bergmaier P. Reichart A. Hauptner R. Krücken H. Strickfaden S. Dietzel T. Cremer G.A. Drexler A.A. Friedl G. Dollinger 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2009,267(12-13):2090-2097
We describe a new setup at the ion microprobe SNAKE (Superconducting Nanoscope for Applied nuclear (Kern-) physics Experiments) at the Munich 14 MV Tandem accelerator that facilitates both living cell irradiation with sub micrometer resolution and online optical imaging of the cells before and after irradiation by state of the art phase contrast and fluorescence microscopy. The cells are kept at standard cell growth conditions at 37 °C in cell culture medium. After irradiation it is possible to switch from single ion irradiation conditions to cell observation within 0.5 s. First experiments were performed targeting substructures of a cell nucleus that were tagged by TexasRed labeled nucleotides incorporated in the cellular DNA by 55 MeV single carbon ion irradiation. In addition we show first online sequences of short time kinetics of Mdc1 protein accumulation in the vicinity of double strand breaks after carbon ion irradiation. 相似文献
74.
Stephan W. Reinhold Thomas Scherl Benjamin Stölcker Tobias Bergler Ute Hoffmann Christian Weingart Miriam C. Banas Dmitrij Kollins Martin C. Kammerl Bernd Krüger Bernhard Kaess Bernhard K. Krämer Bernhard Banas 《Lipids》2013,48(2):167-175
Acute transplant rejection is the leading cause of graft loss in the first months after kidney transplantation. Lipoxygenase products mediate pro- and anti-inflammatory actions and thus we aimed to correlate the histological reports of renal transplant biopsies with urinary lipoxygenase products concentrations to evaluate their role as a diagnostic marker. This study included a total of 34 kidney transplant recipients: 17 with an acute transplant rejection and 17 controls. LTE4, LTB4, 12-HETE and 15-HETE concentrations were measured by enzyme immunoassay. Urinary lipoxygenase product concentrations were not significantly changed during an acute allograft rejection. Nevertheless, LTB4 concentrations correlated significantly with the body temperature (P ≤ 0.05) 3 months after transplantation, and 12- and 15-HETE concentrations correlated significantly with renal function (P ≤ 0.05) 2 weeks after transplantation. In conclusion, our data show a correlation for LTB4 with the body temperature 3 months after transplantation and urinary 12- and 15-HETE concentrations correlate positively with elevated serum creatinine concentrations but do not predict acute allograft rejection. 相似文献
75.
v. Pohl R. Trendelenburg Zimmermann E. Brüche S. Nickel Zycha Liese Schulz Graf A. Troche T. Perkitny M. Lüdtke Frey-Wyssling K. Storch Otto Kratky A. v. Wacek Finkbeiner K. Storch Munds Paula Sarten Ernst Tschanter A. Kraus R. Lechner Schaile Thiele W. Küch Kräß Hengerer Kollmann A. Nowak 《Holz als Roh- und Werkstoff》1940,3(4):128-136
Ohne Zusammenfassung 相似文献
76.
Kräß af Ekenstam R. Trendelenburg Zeller Frey-Wyssling M. Wolf G. Becker Liese Thienhaus Graf A. Troche A. v. Wacek O. Kratky M. Lüdtke Gustav G. Klem Schulz K. Storch Müller E. Becker Klauditz K. Nising A. Nowak L. Metz Egner Fessel Thiele Kraemer Lehnartz Kaiser Tiemann B. Thunell 《Holz als Roh- und Werkstoff》1940,3(11):383-393
Ohne Zusammenfassung 相似文献
77.
Ohne Zusammenfassung 相似文献
78.
79.
Loop closing in vision based SLAM applications is a difficult task. Comparing new image data with all previously acquired image data is practically impossible because of the high computational costs. Most approaches therefore compare new data with only a subset of the old data, for example by sampling the data over time or over space by using a position estimate. In this paper, we propose a more natural approach, which dynamically determines a subset of images that best describes the complete image data in the space of all previously seen images. The actual problem of finding such a subset is called the “Connected Dominating Set” (CDS) problem, which is well studied in the field of graph theory. Application on large indoor datasets results in approximately the same map using only 13% of the computational resources with respect to comparing with all previous images. Also, it outperforms other sampling approaches. The proposed method is particularly beneficial for realistic mapping scenarios including moving objects and persons, motion blur and changing light conditions.1 相似文献
80.
Davide Bilò Hans-Joachim Böckenhauer Dennis Komm Richard Královič Tobias Mömke Sebastian Seibert Anna Zych 《Algorithmica》2011,61(2):227-251
A reoptimization problem describes the following scenario: given an instance of an optimization problem together with an optimal
solution for it, we want to find a good solution for a locally modified instance. 相似文献