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61.
György Csaba Paolo Lugli Markus Becherer Doris Schmitt-Landsiedel Wolfgang Porod 《Journal of Computational Electronics》2008,7(3):454-457
This paper presents a computational study of ion-beam patterned cobalt-platinum multilayers, which could be used for field-coupled
computing. We use micromagnetic simulations to reproduce measured hysteresis curves. This parameterized micromagnetic simulator
then will be used for simulating interacting magnetic dots. We demonstrate how logic gates can be built from such coupled
dots. We also show how electrical wires—placed beneath or above the magnetic dots—can provide a magnetic field, which propagates
the magnetic signals. 相似文献
62.
Franz Ferdinand Reinthaler Gebhard Feierl Herbert Galler Doris Haas Eva Leitner Franz Mascher Angelika Melkes Josefa Posch Ingrid Winter Gernot Zarfel Egon Marth 《Water research》2010,44(6):1981-1985
The aim of this study was to investigate the degree of contamination of sewage sludge with ESBL-producing Escherichia coli strains and the effectiveness of different sewage sludge treatment methods.Monthly sewage sludge samples were collected between January and September 2009 in 5 different sewage treatment plants and tested for the presence of ESBL E. coli. In addition, the number of colony forming units (CFU) of E. coli and coliform bacteria before and after the different sludge treatment methods (aerobic/anaerobic digestion, lime stabilization, and thermal treatment) was investigated.Of the 72 sewage sludge samples investigated, ESBL-positive E. coli were found in 44 (61.1%) sewage sludge samples. The classification of β-lactamase groups was carried out in 15 strains resulting in the detection of 2 different groups (CTX-M and TEM) of bla genes. All 15 of them had a CTX-M gene and 4 of these strains furthermore carried a TEM gene.With regard to the CFU of E. coli and coliform bacteria, thermal treatment and lime stabilization following dehydration sufficiently reduced pathogen concentrations. The plants using merely stabilization and dehydration showed an increase of E. coli and coliform bacteria and thus also an increase in ESBL-producing E. coli. 相似文献
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Element contents in leaves of four plant species (birch, mountain ash, fern and spruce) along anthropogenic and geogenic concentration gradients 总被引:2,自引:0,他引:2
Reimann C Arnoldussen A Boyd R Finne TE Koller F Nordgulen Ø Englmaier P 《The Science of the total environment》2007,377(2-3):416-433
Forty samples each of leaves of birch (Betula pubescens Ehrh.), European mountain ash (Sorbus aucuparia (L.)) and bracken fern (Pteridium aquilinum (L.) Kuhn) as well as spruce needles (Picea abies (L.) Karsten) were collected along a 120 km south-north transect running through Norway's largest city, Oslo. Concentrations of 25 chemical elements (Ag, Au, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, La, Mg, Mn, Mo, Na, Ni, P, Pb, S, Sb, Sr, Ti, and Zn) as well as loss on ignition for the 4 sample materials are reported. The decline of input of sea spray with distance from the coast, geology, pH and anthropogenic contamination all played a role for the observed element concentrations in the leaves. Although growing under exactly the same natural conditions each plant species displayed quite unique uptake characteristics. Plant-species dependency and individual differences in the reaction of the plant leaves to different element sources make the investigated species of very limited value as bioindicators of anthropogenic activities. Anthropogenic contamination influences plant-leaf element content within a limited distance ( approximately 20 km) from the source. 相似文献
66.
Rosa Taurino Elena Fabbri Doris Pospiech Alla Synytska Massimo Messori 《Progress in Organic Coatings》2014
Organic–inorganic hybrid coatings on glass substrates with superhydrophobic properties and with improved scratch resistance were obtained by means of applying a multilayer approach including multiple sol–gel processes. The coatings exhibited a water contact angle (WCA) higher than 150°. Ultraviolet (UV)-curable vinyl ester resins and vinyltriethoxysilane (VTEOS) as coupling agent were employed to increase the adhesion between substrate and the inorganic layers. The surfaces were characterized by means of dynamic contact angle and roughness measurements. Indeed, the occurrence of superhydrophobic behavior was observed. The scratch resistance of the hybrid coatings was tested to evaluate the adhesion of the coatings to the glass substrate. The proposed preparation method for scratch resistant, mechanically stable, superhydrophobic coatings is simple and can be applied on large areas of different kinds of substrates. 相似文献
67.
Berta Esteban-Fernández de Ávila Miguel Angel Lopez-Ramirez Rodolfo Mundaca-Uribe Xiaoli Wei Doris E. Ramírez-Herrera Emil Karshalev Bryan Nguyen Ronnie H. Fang Liangfang Zhang Joseph Wang 《Advanced materials (Deerfield Beach, Fla.)》2020,32(25):2000091
A tubular micromotor with spatially resolved compartments is presented toward efficient site-specific cargo delivery, with a back-end zinc (Zn) propellant engine segment and an upfront cargo-loaded gelatin segment further protected by a pH-responsive cap. The multicompartment micromotors display strong gastric-powered propulsion with tunable lifetime depending on the Zn segment length. Such propulsion significantly enhances the motor distribution and retention in the gastric tissues, by pushing and impinging the front-end cargo segment onto the stomach wall. Once the micromotor penetrates the gastric mucosa (pH ≥ 6.0), its pH-responsive cap dissolves, promoting the autonomous localized cargo release. The fabrication process, physicochemical properties, and propulsion behavior are systematically tested and discussed. Using a mouse model, the multicompartment motors, loaded with a model cargo, demonstrate a homogeneous cargo distribution along with approximately four-fold enhanced retention in the gastric lining compared to monocompartment motors, while showing no apparent toxicity. Therapeutic payloads can also be loaded into the pH-responsive cap, in addition to the gelatin-based compartment, leading to concurrent delivery and sequential release of dual cargos toward combinatorial therapy. Overall, this multicompartment micromotor system provides unique features and advantages that will further advance the development of synthetic micromotors for active transport and localized delivery of biomedical cargos. 相似文献
68.
Harald A. Øye Barry J. Welch 《JOM Journal of the Minerals, Metals and Materials Society》1998,50(2):18-23
There have been tremendous advances in the materials, knowledge, design, and construction of cathodes; however, widelydivergent cell operations and operating conditions present a challenge for selecting the right materials and lining design for good cell life. Cathode wear is frequently becoming the life-determining step, and, although there are questions still to be answered, it is probable that particulate detachment (physical wear) plays an important role in parallel with carbide dissolution. If wear cannot be controlled by smart design and operations, coating technology may offer benefits for extending the life of cathode linings by reducing or eliminating wear. Thus, it would also enable softer graphitic materials to be utilized more readily, and this advantage will become more important if the trend toward higher current density continues. 相似文献
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