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排序方式: 共有415条查询结果,搜索用时 15 毫秒
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A. N. Nateprov V. Ch. Kravtsov V. Fritsch H. von Löhneysen 《Surface Engineering and Applied Electrochemistry》2011,47(6):540-543
The tetragonal modification (space group P4/nmm, no. 129) of the MnCuAs ternary intermetallic compound has been prepared for the first time. The crystallographic data related
to the structure and the atom positions were determined using the X-ray analysis method for MnCuAs single crystals of the
specified modification. The magnetic properties of the tetragonal phase obtained were studied in the temperature range of
5–300 K. 相似文献
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36.
R J Fritsch H Hoffmann H Klostermeyer 《Zeitschrift für Lebensmittel-Untersuchung und -Forschung》1983,176(5):341-345
The heat-induced formation of lysinoalanine (LAL) was studied in raw skim milk that had been subjected to heat treatments as is usual in milk technology. Preheat treatment of milk at temperatures below 100 degrees C up to 20 min resulted in neglectable LAL amounts below 10 ppm i.p. (i.p.=in the protein) if at all. Tests with an UHT pilot plant showed that there was no proven formation of LAL with direct UHT-treatment at 110-130 degrees C for 10-25 min. In indirect UHT-treated milk vert small LAL amouints up to 50 ppm i.p. were detected only in those milk samples that were treated at temperatures high than 145 degrees C and holding times longer than 10 s. Autoclave sterilization in the range of 110-129 degrees C/10-25 min induced LAL amounts of 110 to 710 ppm i.p.. LAL formation in autoclave sterilized milk was almost directly dependent on heating temperature and time. Pre-treatment at temperatures below 100 degrees C induced no further LAL formation in any sterilization processes subsequent to preheating. In the pH range 6,50-6,90 LAL amounts in autoclave-sterilized milk increased directly with higher pH values at all temperatures. The varying degree of LAL formation with pH value was substantially more noticeable at higher than at lower temperatures. Increasing of lactose concentration caused only an insignificant decrease in LAL formation in autoclave-sterilized milk. 相似文献
37.
Effects of sea surface temperature accuracy on offshore wind resource assessment using a mesoscale model
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Susumu Shimada Teruo Ohsawa Tetsuya Kogaki Gerald Steinfeld Detlev Heinemann 《风能》2015,18(10):1839-1854
Offshore wind simulations were performed with the Weather Research and Forecasting (WRF) model driven by three different sea surface temperature (SST) datasets for Japanese coastal waters to investigate the effect of the SST accuracies on offshore wind simulations. First, the National Centers for Environmental Prediction Final analysis (FNL) (1° × 1° grid resolution) and the Operational Sea Surface Temperature and Sea Ice Analysis (OSTIA) (0.05° × 0.05° grid resolution) datasets were compared with in situ measurements. The results show a decrease in accuracy of these datasets toward the coast from the open ocean. Aiming at an improved accuracy of SST data, we developed a new high‐resolution SST dataset (0.02° × 0.02° grid resolution). The new dataset referred to as MOSST is based on the Moderate Resolution Imaging Spectroradiometer (MODIS) product, provided by the Japan Aerospace Exploration Agency (JAXA). MOSST was confirmed to be more accurate than FNL and OSTIA for the coastal waters. Then, WRF simulations were carried out for 1 year with a 2 km grid resolution and by using the FNL, OSTIA and MOSST datasets. The use of the OSTIA dataset for a WRF simulation was found to improve the accuracy when compared with the FNL dataset, and further improvement was obtained when the MOSST dataset was applied. The sensitivity of wind speed and wind energy density to SST is also discussed. We conclude that the use of an accurate SST is a key factor not only for realistic offshore wind simulations near the surface but also for accurate wind resource assessments at the hub height of wind turbines. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
38.
A Kübler B Kotchoubey T Hinterberger N Ghanayim J Perelmouter M Schauer C Fritsch E Taub N Birbaumer 《Canadian Metallurgical Quarterly》1999,124(2):223-232
A thought translation device (TTD) for brain-computer communication is described. Three patients diagnosed with amyotrophic lateral sclerosis (ALS), with total motor paralysis, were trained for several months. In order to enable such patients to communicate without any motor activity, a technique was developed where subjects learn to control their slow cortical potentials (SCP) in a 2-s rhythm, producing either cortical negativity or positivity according to the task requirement. SCP differences between a baseline interval and an active control interval are transformed into vertical or horizontal cursor movements on a computer screen. Learning SCP self regulation followed an operant-conditioning paradigm with individualized shaping procedures. After prolonged training over more than 100 sessions, all patients achieved self-control, leading to a 70-80% accuracy for two patients. The learned cortical skill enabled the patients to select letters or words in a language-supporting program (LSP) developed for inter-personal communication. The results demonstrate that the fast and stable SCP self-control can be achieved with operant training and without mediation of any muscle activity. The acquired skill allows communication even in total locked-in states. 相似文献
39.
Thomas C. Schmidt Gabriel Hege Matthias Wählisch Hans L. Cycon Mark Palkow Detlev Marpe 《Multimedia Tools and Applications》2011,53(2):349-370
The design of conferencing systems for achieving efficient and flexible communication in a fully distributed, infrastructure-independent
fashion is a promising direction, both in terms of research and practical development. In the particular case of video communication,
the seamless adaptation to heterogeneous mobile devices poses an additional strong challenge to those seeking for interoperable
and easy-to-deploy solutions. In this paper, we make several contributions towards a generic peer-to-peer (P2P) videoconferencing
solution that extends into the mobile realm. We describe the essential building blocks for conference management and media
distribution that are necessary for a distributed conferencing approach. Establishing a distributed SIP conference focus,
participants share the conference according to their individually given capabilities and resources in terms of bandwidth and
processing power rather than in a centralized and fixed way. Overall concepts and SIP-primitives for such an autonomous organization
are presented. Security issues that derive from this decentralized identity management are resolved by so-called Overlay AuthoCast, a novel use of cryptographically generated identifiers. Furthermore, this work is dedicated to the development of a software-based
H.264 video codec implementation and the specific aspects resulting from tuning such a highly resource-intensive software
codec to the given target platform of a standard consumer smartphone. 相似文献
40.
A Abo J Qu MS Cammarano C Dan A Fritsch V Baud B Belisle A Minden 《Canadian Metallurgical Quarterly》1998,17(22):6527-6540
The GTPases Rac and Cdc42Hs control diverse cellular functions. In addition to being mediators of intracellular signaling cascades, they have important roles in cell morphogenesis and mitogenesis. We have identified a novel PAK-related kinase, PAK4, as a new effector molecule for Cdc42Hs. PAK4 interacts only with the activated form of Cdc42Hs through its GTPase-binding domain (GBD). Co-expression of PAK4 and the constitutively active Cdc42HsV12 causes the redistribution of PAK4 to the brefeldin A-sensitive compartment of the Golgi membrane and the subsequent induction of filopodia and actin polymerization. Importantly, the reorganization of the actin cytoskeleton is dependent on PAK4 kinase activity and on its interaction with Cdc42Hs. Thus, unlike other members of the PAK family, PAK4 provides a novel link between Cdc42Hs and the actin cytoskeleton. The cellular locations of PAK4 and Cdc42Hs suggest a role for the Golgi in cell morphogenesis. 相似文献