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排序方式: 共有1157条查询结果,搜索用时 18 毫秒
21.
Anastasiia N. Andriianova Lyaysan R. Latypova Liliya Ya. Vasilova Sofia V. Kiseleva Vladimir V. Zorin Ildus B. Abdrakhmanov Akhat G. Mustafin 《应用聚合物科学杂志》2021,138(47):51397
This work presents a detailed study on the effect of various functional groups both at the ortho position of the aromatic ring and in the amino group of PANI on the antibacterial properties of polymers against gram-positive (Bacillus subtilis) and gram-negative (Pseudomonas aureofaciens) microorganisms. It was found that incorporation of methyl, methoxy, or pentyl groups into the ortho-position of PANI did not increase the antibacterial activity but in most cases causes a significant decrease in the antibacterial properties of functionally substituted polyanilines. At the same time, PANI derivatives modified by incorporation of pentyl groups into the amino group were found to be more efficient antibacterial compounds against both gram-positive and gram-negative microorganisms than the original polymer. It was also found that N-substituted PANI derivatives manifest not only bactericidal but also bacteriostatic properties toward the test microorganisms. Varying the nature and position of the substituent allowed us to conclude that the synthesis of various N-substituted PANI derivatives with a high degree of doping is the most promising approach to PANI modification for application in bacterial growth inhibition. 相似文献
22.
TAILORING COMPONENT SUFACES for elevatedtemperature operations has been a goal of researchersduring the last century.Process and material selectionare the key factors for this development.In particularlythe latter can be described to have started with thedevelopment of stainless steels.Ni and Co based alloys,the superalloys,attended the increasing technologicaldemands for higher service temperatures(1).Morerecently the higher operating temperatures ofequipments,such as gas turbines,r… 相似文献
23.
KarinGraf AnaSofiaC.M.d'Oliveira 《材料热处理学报》2004,25(5):152-156
Degradation phenomena like wear and corrosion, may have their effects accelerated as components operate at high temperature. The aim of this work is to make an indirect evaluation of the influence of high temperature exposure on wear behavior of Ni coatings. A Ni-Cr-Mo-W alloy, was deposited with Plasma Transferred Arc (PTA) process. An indirect approach based on the Ahrrenius relationship was used to evaluated long time exposures at high temperatures. To simulate longer exposures at lower temperatures, coatings were exposed to higher temperatures for the same time interval. So coatings were soaked in an air furnace at 650℃, 1000℃ and 1200℃. Metal/metal wear behavior was evaluated by pin-on-disc tests. Pins were removed from the coatings by eletrodischarge machining and rubbed against a VC31 quenched and tempered tool steel. Two sets of wear tests were run at 2m/s, for different loads (0.5, 1.0, 2.0 and 3.0Kg) and for different sliding distances (120, 720, 1080, 1440 and 1800m).Coatings characterization was done by scanning electronic microscopy and Vickers microhardness. Results showed as temperature is increased, coatings wear performance is altered,and this is associated with microstructural changes. 相似文献
24.
Konstantinos Makantasis Eftychios Protopapadakis Anastasios Doulamis Nikolaos Doulamis Nikolaos Matsatsinis 《Multimedia Tools and Applications》2016,75(22):15017-15049
Falls have been reported as the leading cause of injury-related visits to emergency departments and the primary etiology of accidental deaths in elderly. Thus, the development of robust home surveillance systems is of great importance. In this article, such a system is presented, which tries to address the fall detection problem through visual cues. The proposed methodology utilizes a fast, real-time background subtraction algorithm, based on motion information in the scene and pixels intensity, capable to operate properly in dynamically changing visual conditions, in order to detect the foreground object. At the same time, it exploits 3D space’s measures, through automatic camera calibration, to increase the robustness of fall detection algorithm which is based on semi-supervised learning approach. The above system uses a single monocular camera and is characterized by minimal computational cost and memory requirements that make it suitable for real-time large scale implementations. 相似文献
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Hybrid TDMA (Time Division Multiple Access) with heuristic traffic shaping (HyTDMA/HTS) is a new collisionless MAC protocol for efficiently managing the traffic of a heavy loaded broadcast LAN. The protocol employs techniques that enable it to perform better than both fixed assignment protocols like TDMA as well as dynamic bandwidth allocation protocols like LTDMA. HyTDMA/HTS can smoothly operate in diverse traffic environments of very high loads and bursty traffic, and it can still maintain maximum shared medium utilization while maintaining low packet delay times. Built into the protocol is also a simple yet effective heuristic mechanism that regulates the traffic of hosts flooding the network with an excessive number of packets larger than the average. 相似文献
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28.
Jürgen Kühling Anastasios Sivridis Mathis Schwuchow Thorben Burghardt 《Datenschutz und Datensicherheit - DuD》2009,33(6):335-342
Zusammenfassung Die Autoren untersuchen das datenschutzrechtliche Vollzugsdefizit im Anwendungsbereich des Telemediengesetzes. Ihr Ergebnis
ist, dass das Ausma? des datenschutzrechtlichen Vollzugsdefizits der von au?en zu überprüfenden datenschutzrechtlichen Pflichten
der Anbieter „erschreckend“ ist. Nur einem ganz geringen Teil der Anbieter gelingt es, sich rechtskonform zu verhalten.
Prof. Dr. Jürgen Kühling Inhaber eines Lehrstuhls für ?ffentliches Recht an der Universit?t Regensburg.
Anastasios Sivridis wissenschaftlicher Mitarbeiter und Doktorand am Lehrstuhl Prof. Kühling.
Mathis Schwuchow studentische Hilfskraft am Lehrstuhl Prof. Kühling.
Thorben Burghardt wissenschaftlicher Mitarbeiter und Doktorand am Lehrstuhl für Systeme der Informationsverwaltung (TH Karlsruhe). 相似文献
29.
Segkouli Sofia Giakoumis Dimitrios Votis Konstantinos Triantafyllidis Andreas Paliokas Ioannis Tzovaras Dimitrios 《Universal Access in the Information Society》2023,22(1):37-49
Universal Access in the Information Society - Pervasive technologies such as Artificial Intelligence, Virtual Reality and the Internet of Things, despite their great potential for improved... 相似文献
30.
Fouto Ana R. Nunes Rita G. Pinto Joana Alves Luísa Calado Sofia Gonçalves Carina Rebolo Margarida Viana-Baptista Miguel Vilela Pedro Figueiredo Patrícia 《Magma (New York, N.Y.)》2022,35(5):779-790
Magnetic Resonance Materials in Physics, Biology and Medicine - Histogram-based metrics extracted from diffusion-tensor imaging (DTI) have been suggested as potential biomarkers for cerebral small... 相似文献