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11.
Pezeshki A. Scharf L.L. Azimi-Sadjadi M.R. Yingbo Hua 《Signal Processing, IEEE Transactions on》2005,53(1):121-135
The problem of two-channel constrained least squares (CLS) filtering under various sets of constraints is considered, and a general set of solutions is derived. For each set of constraints, the solution is determined by a coupled (asymmetric) generalized eigenvalue problem. This eigenvalue problem establishes a connection between two-channel CLS filtering and transform methods for resolving channel measurements into canonical or half-canonical coordinates. Based on this connection, a unified framework for reduced-rank Wiener filtering is presented. Then, various representations of reduced-rank Wiener filters in canonical and half-canonical coordinates are introduced. An alternating power method is proposed to recursively compute the canonical coordinate and half-canonical coordinate mappings. A deflation process is introduced to extract the mappings associated with the dominant coordinates. The correctness of the alternating power method is demonstrated on a synthesized data set, and conclusions are drawn. 相似文献
12.
The connected home of the future, in which all consumer appliances in a home are networked together, is close to becoming the connected home of today. This article explores the role of fault diagnosis in such an environment and explains how agent technology may be applied. The article outlines the need for future standards that can maximize the benefit of a shared diagnostic system. 相似文献
13.
Jürgen K. P. Weder Udo Scharf 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1981,172(3):185-189
Summary Fingerprinting (thin-layer electrophoresis/chromatography) after tryptic or chymotryptic digestion of performic acid-oxidized monomeric, dimeric, and oligomeric ribonuclease isolated from heated ribonuclease and monomeric unheated ribonuclease demonstrates one additional peptide in all heated samples. Preparative ion-exchange chromatography of the tryptic digests results in the corresponding number of fractions, 15 and 14, respectively. Amino acid analysis andN-terminal amino acid determination relate most of these peptides to theoretical tryptic peptides, whilst some are formed by further fragmentation due to chymotryptic activity of the commercial TPCK-trypsin used. This is also true of the additional peptide found in heated samples. So no distinct crosslinking peptide could be demonstrated. Only favoured participation of theN-terminal region in crosslinking is indicated. The observed differences between heated and unheated samples must be due to differences in three-dimensional structure leading to differences in susceptibility for proteolytic enzymes. Demonstration of both isopeptides, aspartyllysine and glutamyllysine, in three out of five fractions from digests of ribonuclease dimer, indicating six different isopeptide crosslinks, confirms the assumption of a very unspecific formation of crosslinks during protein heating.
We thank the Deutsche Forschungsgemeinschaft for supporting this work and Mrs. Anneliese Mödl and Mrs. Angelika Langwieser for performing the amino acid analyses 相似文献
Modelluntersuchungen über das Erhitzen von Lebensmittelproteinen —Oligomerisierung von Ribonuclease beim ErhitzenIII. Über die Lokalisierung säurelabiler Brückenpeptide
Zusammenfassung Durch zweidimensionale Dünnschichtelektrophorese/-chromatographie nach tryptischer oder chymotryptischer Spaltung perameisensäureoxidierter monomerer, dimerer und oligomerer Ribonuclease aus erhitzter Ribonuclease sowie monomerer unerhitzter Ribonuclease wurde ein zusätzliches Peptid in allen erhitzten Proben nachgewiesen. Durch präparative Ionenaustauscherchromatographie tryptischer Hydrolysate wurden dementsprechend 15 bzw. 14 Fraktionen erhalten. Durch Aminosäureanalyse und Bestimmung derN-terminalen Aminosäuren konnten die meisten Peptide theoretischen tryptischen Spaltpeptiden zugeordnet werden, während einige durch weitergehende Spaltung aufgrund chymotryptischer Nebenaktivitäten im verwendeten TPCK-Trypsinpräparat gebildet werden. Dies gilt auch für das in erhitzten Proben zusätzlich gefundene Peptid, so daß kein spezifisches Brückenpeptid nachgewiesen werden konnte. Lediglich eine bevorzugte Beteiligung desN-terminalen Bereiches an Quervernetzungsreaktionen ist erkennbar. Die beobachteten Unterschiede zwischen erhitzten und unerhitzten Proben beruhen auf unterschiedlicher räumlicher Anordnung, die zu Unterschieden in der Zugänglichkeit für proteolytische Enzyme führt. In drei von fünf untersuchten Fraktionen tryptisch gespaltener dimerer Ribonuclease konnten jeweils beide Isopeptide, Aspartyl-lysin und Glutamyl-lysin, also insgesamt sechs verschiedene Isopeptidbrücken nachgewiesen werden. Damit wird die Annahme einer sehr unspezifischen Brückenbildung während der Proteinerhitzung bestätigt.
We thank the Deutsche Forschungsgemeinschaft for supporting this work and Mrs. Anneliese Mödl and Mrs. Angelika Langwieser for performing the amino acid analyses 相似文献
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The techniques peculiar to dynamic programming have found a variety of successful applications in the theory and practice of modern control. Successes in the theory and practice of signal and image processing are less numerous and prominent, but they do exist. In this paper, we sound a call for renewed attention to the potential of dynamic programming for solving knotty, nonlinear filtering problems in signal and image processing, and outline successes we have recently enjoyed in nonlinear frequency tracking and random boundary estimation in noisy black and white images. Two classical results, the fast Fourier transform and Levinson's recursion for determining autoregressive parameters, are treated in the context of dynamic programming simply to reinforce the point that many of the algorithms we take for granted, and which were derived without recourse to dynamic programming, can be nicely interpreted as dynamic programming algorithms. 相似文献
17.
Claus Schreiner Sabine Scharf Volkmar Stenzel Albert Rössler 《Journal of Coatings Technology and Research》2017,14(4):809-816
The use of microcapsules containing healing agents, which can serve as source of self-healing for coatings, was investigated. The appropriate self-repairing coatings are designed to be used for heavy-duty corrosion protection or for the protection of moisture-sensitive substrates like wood. Microcapsules based on thermoset resins (urea–formaldehyde and melamine–formaldehyde) which contained components of different chemical natures (resins or inhibitors) were fabricated using emulsion techniques. The subsequent characterization included optical, fluorescence, and electron microscopy as well as adapted microindentation techniques to determine capsule break forces. Different model coatings were formulated making use of varying amounts of healing agent-charged microcapsules. The coated samples were then injured under controlled conditions (by Erichsen cupping in the case of steel, by simulated hail in the case of wood) and then subjected to salt spray testing (natural and accelerated), weathering, or even real-life exposure, always in comparison with a blank. The results obtained demonstrate the superiority of microcapsule-based self-healing coatings compared to classical protection formulations, and appropriate coating systems have in the meantime been successfully brought to the market. 相似文献
18.
W.S. Rubink V. Ageh H. Lide N.A. Ley M.L. Young D.T. Casem E.J. Faierson T.W. Scharf 《Journal of the European Ceramic Society》2021,41(6):3321-3332
Spark plasma sintering (SPS) was employed to consolidate powder specimens consisting of B4C and various B4C-TiB2 compositions. SPS allowed for consolidation of pure B4C, B4C-13 vol.%TiB2, and B4C-23 vol.%TiB2 composites achieving ≥99 % theoretical density without sintering additives, residual phases (e.g., graphite), and excessive grain growth due to long sintering times. Electron and x-ray microscopies determined homogeneous microstructures along with excellent distribution of TiB2 phase in both small and larger-scaled composites. An optimized B4C-23 vol.%TiB2 composite with a targeted low density of ~3.0 g/cm3 exhibited 30–35 % increased hardness, fracture toughness, and flexural bend strength compared to several commercial armor-grade ceramics, with the flexural strength being strain rate insensitive under quasistatic and dynamic loading. Mechanistic studies determined that the improvements are a result of a) no residual graphitic carbon in the composites, b) interfacial microcrack toughening due to thermal expansion coefficient differences placing the B4C matrix in compression and TiB2 phase in tension, and c) TiB2 phase aids in crack deflection thereby increasing the amount of intergranular fracture. Collectively, the addition of TiB2 serves as a toughening and strengthening phase, and scaling of SPS samples show promise for the manufacture of ceramic composites for body armor. 相似文献
19.
Groundwater heads were mapped for the entire State of Mecklenburg-Western Pomerania by applying a Detrended Kriging method based on a numerical geohydraulic model. The general groundwater flow system (trend surface) was represented by a two-dimensional horizontal flow model. Thus deviations of observed groundwater heads from simulated groundwater heads are no longer subject to a regional trend and can be interpolated by means of Ordinary Kriging. Subsequently, the groundwater heads were obtained from the sum of the simulated trend surface and interpolated residuals. Furthermore, the described procedure allowed a plausibility check of observed groundwater heads by comparing them to results of the hydraulic model. If significant deviations were seen, the observation wells could be allocated to different aquifers. The final results are two hydraulically established groundwater head distributions – one for the regional main aquifer and one for the upper aquifer which may differ locally from the main aquifer. 相似文献
20.
Transfusion of whole blood is the most common and successful organ transplantation world wide. It is in use longer than any other transplantation procedure. With the exception of uses in situations of crisis, treatment with whole blood is nowadays obsolete. This is due to enormous progress in preparation technologies. As a result blood from volunteer donors is separated before therapeutic use into its cellular and plasmatic components. The latter may be further processed into subfractions or secondary products. The advantages of this strategy are evident: a) the crude pharmaceutic material blood is used optimally, b) the isolated components may be stored over periods appropriate for their stability be it in a cryopreserved state or after biochemical, immunologic or biological modification, c) the patient receives only the blood components he needs, d) the transfusion of unnecessary fractions of blood is avoided, e) the rate of transfusion-associated adverse events is reduced, f) the physician has a basis for customized hematotherapy. Important implications concern logistics, economy, differentiated therapy and drug safety consideration. This contribution gives an overview on progress made in therapy of hematologic and oncologic patients with blood products and concentrates of coagulation factors. It demonstrates selected aspects of actual interest for optimal hemotherapy. 相似文献