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排序方式: 共有277条查询结果,搜索用时 31 毫秒
51.
Matías Bejide Patricio Contreras Pia Homm Boris Duran Jos Antonio García-Merino Andreas Rosenkranz Juliano C. Denardin Rodrigo del Río Samuel A. Hevia 《Molecules (Basel, Switzerland)》2020,25(22)
Nickel nanopillar arrays were electrodeposited onto silicon substrates using porous alumina membranes as a template. The characterization of the samples was done by scanning electron microscopy, X-ray diffraction, and alternating force gradient magnetometry. Ni nanostructures were directly grown on Si by galvanostatic and potentiostatic electrodeposition techniques in three remarkable charge transfer configurations. Differences in the growth mechanisms of the nanopillars were observed, depending on the deposition method. A high correlation between the height of the nanopillars and the charge synthesis was observed irrespective of the electrochemical technique. The magnetization measurements demonstrated a main dependence with the height of the nanopillars. The synthesis of Ni nanosystems with a controllable aspect ratio provides an effective way to produce well-ordered networks for wide scientific applications. 相似文献
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José Antonio Carrillo Maria Pia Gualdani Giuseppe Toscani 《Comptes Rendus Mathematique》2004,338(10):815-818
In this Note we make use of mass transportation techniques to give a simple proof of the finite speed of propagation of the solution to the one-dimensional porous medium equation. The result follows by showing that the difference of support of any two solutions corresponding to different compactly supported initial data is a bounded in time function of a suitable Monge–Kantorovich related metric. To cite this article: J.A. Carrillo et al., C. R. Acad. Sci. Paris, Ser. I 338 (2004). 相似文献
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Armstrong TA Bettoni D Bharadwaj V Biino C Borreani G Broemmelsiek D Buzzo A Calabrese R Ceccucci A Cester R Church MD Dalpiaz P Dalpiaz PF Fast JE Ferroni S Ginsburg CM Gollwitzer KE Hahn AA Hasan MA Hsueh SY Lewis RA Luppi E Macr M Majewska A Mandelkern MA Marchetto F Marinelli M Marques JL Marsh W Martini M Masuzawa M Menichetti E Migliori A Mussa R Palestini S Pastrone N Patrignani C Peoples J Pesando L Petrucci F Pia MG Pordes S Rapidis PA Ray RE Reid JD Rinaudo G Rosen JL Santroni A 《Physical review letters》1992,68(10):1468-1471
56.
Finite linear spaces on v points with v–2 mutually intersecting long lines are completely characterized.Dedicated to Professor Giuseppe Tallini on the occasion of his 60th birthday.Work supported by Italian M.P.I. 8nd by GNSAGA of CNR 相似文献
57.
Emanuele Dell’Aglio Susanne Heidi Plattner Maria Pia Sammartino Giovanni Visco Luigi Campanella 《Natural product research》2019,33(7):1026-1033
AbstractResearch in restoration and conservation is directed vs. more sustainable working materials, methods and technologies. Electrophoretic removal, from porous material, of undesired stains due to charged species is theoretically an interesting alternative to chemical cleaning methods, but the lack of specific and comprehensive research work leads to controversial opinions about the efficiency and the needed harmfulness for the treated objects. In this work paper, samples with artificial rust stains were subjected to electrophoretic cleaning treatments in mineral water as electrolyte. Treatments were carried out either in a bath by complete sample immersion between the distanced electrodes or by sample wetting and sandwiching between the electrodes. Evaluation of cleaning efficiency and treatment effects was based on colour change measurements (image analysis of scanned paper samples before and after the treatment and by colorimetric data via spectrophotometric measurements), investigation of morphological changes by SEM observations and folding endurance measurements. 相似文献
58.
Salvatore Passannanti Maria Pia Paternostro Franco Piozzi Giuseppe Savona 《Journal of heterocyclic chemistry》1977,14(1):103-106
The synthesis of several isoearboslyrils is reported, including lorrnyl derivatives at (1-4, like nareiclasie aldehyde (I) and the homologous aldehyde (XV). 相似文献
59.
Bhikhabhai R Sjöberg A Hedkvist L Galin M Liljedahl P Frigård T Pettersson N Nilsson M Sigrell-Simon JA Markeland-Johansson C 《Journal of chromatography. A》2005,1080(1):83-92
A new chromatography system, AKTAxpress (GE Healthcare, Amersham Biosciences, Uppsala, Sweden) has been designed to meet the demand for high-throughput purification of proteins in structural genomics and drug discovery. The system offers a number of automated multistep purification protocols for affinity-tagged proteins. All protocols start with affinity chromatography followed by combinations of desalting, ion exchange chromatography and gel filtration. As an option, tag removal can be included in the purification protocols. Up to 16 proteins can be purified per day and the yield can be as high as 50 mg of each protein at > 90% purity. To highlight the versatility of the system, this paper presents several case studies; purifications of hexahistidine- and glutathione S-transferase-tagged proteins using different protocols, automated on-column tag cleavage and optimization studies for a hexahistidine-tagged kinase. 相似文献
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