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A comparative analysis of crude protein, crude ash, phosphorus (P), potassium (K) and calcium (Ca) contents of 57 samples of eight common edible mushroom species was made. The most important protein sources were: Marasmius oreades and Lepista nebularis. Species of the Boletaceae formed an intermediate group, while relatively proteinless species were: Armillariella mellea and Cratarellus cornucopioides. The lowest crude protein content was established in Cantharellus cibarius. The ash contents varied more widely. The greatest P contents were measured in Lepista nebularis and Marasmius oreades but most mushrooms contained 6-7 gP/kg. The analysed mushroom samples contained 30-40 gK/kg dry weight and 0,2-0,3 gCa/kg. These analyses are important from the point of view of the nutritional role of mushrooms.  相似文献   
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Surface treatments used in daily manufacturing of parts for the automotive industry are selected to serve functional and decorative requirements achieved of mass production. Increased loads (mechanical, thermal etc.), longer life time, weight reduction, friction reduction, and corrosion resistance are demanded for modern automotive systems. Within the last decade, improved and new deposition techniques were developed in PVD, PECVD, thermochemical heat treatment and thermal spraying. These new treatments are becoming more and more common in powertrain and engine applications. Generating optimized surfaces for different types of substrate materials (e.g. Al‐ alloys, case hardened steels etc.) and geometries (e.g. bores) also impacts the running costs. Due to the new developments within these competing surface treatments, it becomes more and more common to substitute traditional treatment‐substrate‐systems with advanced treatments. Both the application potential and selected examples of different surface treatments will be shown. Aspects of the internal coating of bores inside the engine by plasma spraying, features of the corrosion protection of parts for the powertrain by the IONITOX process and piston ring treatments are discussed in more detail.  相似文献   
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Vetter  R.J. Severance  C. 《Computer》1997,30(11):139-143
The World Wide Web has the potential to revolutionize instruction and increase educational opportunities across corporate, government and educational sectors. Not only will the Web enable distance learning and peer-to-peer connectivity, but it will also enhance student feedback and let instructors understand whether and how long students have studied a particular lesson. It also has the potential to reduce training costs. The authors discuss the creation of an online learning environment considering practical and pedagogical issues  相似文献   
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The behavioral and electrophysiological activity of a mimic [(Z,E)7,9,11-dodecatrienyl formate] of the major sex pheromone component [(Z,E) 9,11,13-tetradecatrienal] of carob moth was assessed. Wind-tunnel bioassays demonstrated that the formate was as effective as natural gland extracts, and significantly more effective than the trienal alone or than the trienal blended with two minor pheromone components, in evoking source contact. Dispensers containing the formate were as effective as trienal-containing blend lures in attracting males when placed at the same dosage in traps in date gardens. Single-cell recordings showed that at least two olfactory neurons, differentiated by spike amplitude, are located in the long trichoid hairs on male carob moth antennae. Dose-response relationships indicated that puffs from cartridges loaded with at least 0.1 g of the formate or of the trienal were necessary to elicit spiking by either the small or the large-spiking cell within a sensillum. Cross-adaptation studies demonstrated that both compounds stimulated the same large-spiking cell. The frequencies of spikes evoked from the large cell when stimulated by emissions from 0.1-g, 1-g, or 10-g cartridges of either the formate or the trienal were not significantly different, suggesting that the formate is an effective mimic of the trienal at the antennal receptor cell level.  相似文献   
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Varshney  U. Vetter  R.J. Kalakota  R. 《Computer》2000,33(10):32-38
Electronic commerce continues to see phenomenal growth, but so far most e-commerce development involves wired infrastructures. The authors believe emerging wireless and mobile networks will provide new avenues for growth, creating new opportunities in mobile commerce. According to the GartnerGroup, a market research firm, by 2004 at least 40 percent of consumer-to-business e-commerce will come from smart phones using the wireless application protocol (WAP). Based on a study by the Wireless Data and Computing Service, a division of Strategy Analytics, the annual mobile commerce market may rise to $200 billion by 2004. The authors provide a mobile commerce framework to illustrate potential applications such as mobile inventory management, product location and search, proactive service management, and mobile entertainment. They also describe the wireless user and networking infrastructure, emerging W3C standards, and the open and global WAP specification  相似文献   
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Global Address Space (GAS) programming models enable a convenient, shared-memory style addressing model. Typically this is realized through one-sided operations that can enable asynchronous communication and data movement. With the size of petascale systems reaching 10,000s of nodes and 100,000s of cores, the underlying runtime systems face critical challenges in (1) scalably managing resources (such as memory for communication buffers), and (2) gracefully handling unpredictable communication patterns and any associated contention. For any solution that addresses these resource scalability challenges, equally important is the need to maintain the performance of GAS programming models. In this paper, we describe a Hierarchical COOperation (HiCOO) architecture for scalable communication in GAS programming models. HiCOO formulates a cooperative communication architecture: with inter-node cooperation amongst multiple nodes (a.k.a multinode) and hierarchical cooperation among multinodes that are arranged in various virtual topologies. We have implemented HiCOO for a popular GAS runtime library, Aggregate Remote Memory Copy Interface (ARMCI). By extensively evaluating different virtual topologies in HiCOO in terms of their impact to memory scalability, network contention, and application performance, we identify MFCG as the most suitable virtual topology. The resulting HiCOO architecture is able to realize scalable resource management and achieve resilience to network contention, while at the same time maintaining or enhancing the performance of scientific applications. In one case, it reduces the total execution time of an NWChem application by 52%.  相似文献   
10.
Flexible barriers are increasingly used for the protection from debris flow in mountainous terrain due to their low cost and environmental impact. However, the development of a numerical tool for the rational design of such structures is still a challenge. In this work, a hybrid computational framework is presented, using a total Lagrangian formulation of the finite element method to represent a flexible barrier. The actions exerted on the structure by a debris flow are obtained from simultaneous simulations of the flow of a fluid‐grain mixture, using two conveniently coupled solvers: the discrete element method governs the motion of the grains, while the free‐surface non‐Newtonian fluid phase is solved using the lattice Boltzmann method. Simulations on realistic geometries show the dependence of the momentum transfer on the barrier on the composition of the debris flow, challenging typical assumptions made during the design process today. In particular, we demonstrate that both grains and fluid contribute in a nonnegligible way to the momentum transfer. Moreover, we show how the flexibility of the barrier reduces its vulnerability to structural collapse, and how the stress is distributed on its fabric, highlighting potential weak points.  相似文献   
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