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排序方式: 共有2423条查询结果,搜索用时 31 毫秒
11.
The design of controlled-resistance loads for domestic induction heating applications using thin non-magnetic conductive layers is described. Thin metallic layers are fabricated using the phase vapour deposition technique. Such layers would enable vessels, the inductive behaviour of which was similar to those fabricated with conventional ferromagnetic bulk materials, to be manufactured. Optimum layer thickness is investigated using an analytical impedance model of the complete induction system 相似文献
12.
Marie Alonso 《印刷技术》2002,(5)
当数码印刷、种类繁多的承印物以及经过改进的覆膜技术为印制精美耐用的户内、户外广告招贴的应用开辟了一条新的道路,建立了一种宽渠道的盈利模式时,宽幅印刷已经走向 相似文献
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ABSTRACT: We evaluated the effect of growth environment on morphology and fatty acid (FA) profiles of 2 strains of C ampylobacter jejuni (ATCC 29428 and 33560) grown under various gaseous conditions. Viable counts were determined by plate count and percentages of coccoid cells. FA profiles were measured by gas chromatography. Plate counts were lowest when cultures were grown in air and highest in CO2 (10%), O2 (5%), and N2 (85%). For 29428, percentages of coccoid cells did not differ among treatments. For 33560, percentages of coccoid cells were greater than for 29428 and varied among treatments (13% to 87%). There were no significant ( P > 0.05) relationships between percentages of coccoid cells and amounts of individual or combinations of FA either between or within strains. 相似文献
16.
Nadia Ben Atti Gema M. Diaz–Toca Henri Lombardi 《Applicable Algebra in Engineering, Communication and Computing》2006,17(1):75-82
We propose a slight modification of the Berlekamp-Massey Algorithm for obtaining the minimal polynomial of a given linearly
recurrent sequence. Such a modification enables to explain it in a simpler way and to adapt it to lazy evaluation.
partially supported by the Galois Theory and Explicit Methods in Arithmetic Project HPRN-CT-2000-00114
partially supported by the European Union funded project RAAG CT-2001-00271 相似文献
17.
Modern computers have enjoyed increasing storage capacity, but the mechanisms that harness this storage power haven't improved proportionally. Whether current desktops have scaled to handle the enormous number of files computers must handle compared to just a few years ago is doubtful at best. Scalability includes not only fault tolerance or performance stability of tools for users to harness this power. The lack of appropriate structures and tools for locating, navigating, relating, and sharing bulky file sets is preventing users from harnessing their PCs' full storage power. Powering desktops with metadata, leading to the semantic desktop, is a promising way to realize this potential. The seMouse approach realizes the promising vision of the semantic desktop. This approach provides seamless integration between file-centered tooling and semantically aware, resource-centered applications. 相似文献
18.
A significant relationship between sex ratio and litter size at birth was observed in the young of guinea-pigs caged singly from 8 weeks of age and during their first pregnancy; a male was present only at or around oestrus. Small litters (1-2 young) had significantly more males than did large litters (4-5 young). Such a relationship was not apparent in animals housed communally, whether young or older or in their second pregnancy. Litters in late pregnancy (day 63) or at delivery were significantly smaller than at mid-pregnancy (day 35). A significant negative relationship was found between litter size and bodymass at birth and to at least 63 days of age. Growth rates during the period of lactation were lower in animals born in large litters. The possible adaptive significance of a plastic relationship between litter size and sex ratio is considered together with the physiological mechanism that might be involved. 相似文献
19.
RM Hendry CV Hanson V Bongertz M Morgado A Duarte J Casseb L Brigido E Sabino R Diaz B Galv?o-Castro 《Canadian Metallurgical Quarterly》1996,91(3):347-348
The influence of noncompetitive (MK-801), competitive (AP-7) and the antagonist of polyamines site of NMDA receptor (arcaine) on the central activity of angiotensin II (A II) was studied. The open field test, conditioning of active avoidance responses (CARs) and passive avoidance situation was used to investigate learning and memory in rats. All used antagonists decreased beneficial action of A II on these processes. 相似文献
20.
EL Romano RF Monta?o B Brito R Apitz J Alonso M Romano S Gebrán A Soyano 《Canadian Metallurgical Quarterly》1997,19(1):15-36
An increasing flow of evidences collected on elementary forms of learning processes in selected animal models evidentiates some mechanisms which can represent the basic cellular principles underlying plastic changes: 1. 5HT and second messengers of nucleotide type (like cAMP) have a pivotal role in the learning process. 2. In almost all short-term learning processes the modifications are subserved by a mechanism of protein phosphorylation. 3. In various animal models the modulation of K+ and Ca2+ channels is the molecular mechanism for learning. Experiments performed in sensory T neuron of the leech indicate that the modulation of Na+/K+ electrogenic pump is one of the fundamental mechanism for learning. 4. In long-term plastic changes, the most important finding is that newly synthesized proteins are formed. 5. In addition to what has been observed in the Aplysia model, where changes in synaptic efficacy represent the basic principles of memory storage, in the leech it has been demonstrated that a molecular machinery present in a single neuron can adapt the activity of the cell to environmental stimuli. 相似文献