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981.
How to achieve consistency for 3D city models 总被引:1,自引:1,他引:0
Consistency is a crucial prerequisite for a large number of relevant applications of 3D city models, which have become more
and more important in GIS. Users need efficient and reliable consistency checking tools in order to be able to assess the
suitability of spatial data for their applications. In this paper we provide the theoretical foundations for such tools by
defining an axiomatic characterization of 3D city models. These axioms are effective and efficiently supported by recent spatial
database management systems and methods of Computational Geometry or Computer Graphics. They are equivalent to the topological
concept of the 3D city model presented in this paper, thereby guaranteeing the reliability of the method. Hence, each error
is detected by the axioms, and each violation of the axioms is in fact an error. This property, which is proven formally,
is not guaranteed by existing approaches. The efficiency of the method stems from its locality: in most cases, consistency
checks can safely be restricted to single components, which are defined topologically. We show how a 3D city model can be
decomposed into such components which are either topologically equivalent to a disk, a sphere, or a torus, enabling the modeling
of the terrain, of buildings and other constructions, and of bridges and tunnels, which are handles from a mathematical point
of view. This enables a modular design of the axioms by defining axioms for each topological component and for the aggregation
of the components. Finally, a sound, consistent concept for aggregating features, i.e. semantical objects like buildings or
rooms, to complex features is presented. 相似文献
982.
Gerhard Kramarz von Kohout 《Datenschutz und Datensicherheit - DuD》2016,40(5):315-317
Kann ein Notruf auch bei Stromausfall abgesetzt werden? Müssen schon heute Notrufe aus IP-Netzen ermöglicht werden? Der folgende Artikel diskutiert die zugrunde liegenden Sachverhalte aus rechtlicher und technischer Sicht und gibt Antworten auf die beiden vielfach gestellten Fragen. 相似文献
983.
984.
Microelectronics: Biomimetic Microelectronics for Regenerative Neuronal Cuff Implants (Adv. Mater. 43/2015)
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985.
986.
Harald Mangge Florian Prüller Sieglinde Zelzer Herwig Ain?dhofer Sabine Pailer Petra Kieslinger Johannes Haybaeck Barbara Obermayer-Pietsch Gerhard Cvirn Hans-Jürgen Gruber 《International journal of molecular sciences》2015,16(7):15776-15784
Clotting abnormalities are discussed both in the context with thyroid dysfunctions and obesity caused by a high fat diet. This study aimed to investigate the impact of hypo-, or hyperthyroidism on the endogenous thrombin potential (ETP), a master indicator of clotting activation, on Sprague Dawley rats fed a normal or high fat diet. Female Sprague Dawley rats (n = 66) were grouped into normal diet (ND; n = 30) and high-fat diet (HFD; n = 36) groups and subdivided into controls, hypothyroid and hyperthyroid groups, induced through propylthiouracil or triiodothyronine (T3) treatment, respectively. After 12 weeks of treatment ETP, body weight and food intake were analyzed. Successfully induced thyroid dysfunction was shown by T3 levels, both under normal and high fat diet. Thyroid dysfunction was accompanied by changes in calorie intake and body weight. In detail, compared to euthyroid controls, hypothyroid rats showed significantly increased—and hyperthyroid animals significantly decreased—ETP levels. High fat diet potentiated these effects in both directions. In summary, we are the first to show that hypothyroidism and high fat diet potentiate the thrombotic capacity of the clotting system in Sprague Dawley rats. This effect may be relevant for cardiovascular disease where thyroid function is poorly understood as a pathological contributor in the context of clotting activity and obesogenic nutrition. 相似文献
987.
988.
Wireless Microfluidic Systems for Programmed,Functional Transformation of Transient Electronic Devices
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Chi Hwan Lee Seung‐Kyun Kang Giovanni A. Salvatore Yinji Ma Bong Hoon Kim Yu Jiang Jae Soon Kim Lingqing Yan Dae Seung Wie Anthony Banks Soong Ju Oh Xue Feng Yonggang Huang Gerhard Troester John A. Rogers 《Advanced functional materials》2015,25(32):5100-5106
Electronic systems that enable programmable transformation of functional behaviors by remote control or by autonomous responses to user‐defined circumstances create unusual engineering opportunities, where physical changes in the hardware induce desired changes in operation. This paper presents materials and device architectures for technologies of this type, in which localized microfluidic chemical etching of targeted constituent components in the electronics occurs in a sequential, selective manner. Custom circuits that include reconfigurable radio‐powered thermal actuators with analog amplifiers and square waveform generators illustrate the concepts. 相似文献
989.
Jinhua Wang Herbert Wieser Elke Pawelzik Joachim Weinert Anna J. Keutgen Gerhard A. Wolf 《European Food Research and Technology》2005,220(5-6):552-559
Samples artificially infected by Fusarium culmorum were analyzed to assess the effects of Fusarium infection on the protein quality of winter wheat (Triticum aestivum L.). The Fusarium infection did not noticeably influence either the crude protein content or the water absorption ability of the wheat flour. The protease activity found in the wheat flour was inversely correlated to the sedimentation value. In contrast, it was positively correlated to both the free amino acid content and the degree of infection as expressed in Fusarium protein equivalents (FPE) quantified by an enzyme-linked immunosorbent assay. A distinct reduction in the content of both total glutenin and high molecular weight glutenin subunits was detected in the seriously infected samples (FPE>20 µg g–1). The infection with Fusarium impaired the dough quality and led to a deformed loaf shape. The fungal protease was active over both a wide range of temperatures (from 10 to 100 °C) and a wide range of pH values (from 4.5 to 8.5). The maximum protease activity was displayed at 50 °C in the pH range 6.0–8.0. This property indicates that the protease produced by F. culmorum may impair storage proteins throughout all the processing procedures associated with wheat flour, thereby causing weak dough properties and, consequently, unsatisfactory bread quality. 相似文献
990.
End-sealed 60×60×250?mm3 Pinus radiata pieces were dried at 65/37 °C (dry bulb/wet bulb temperature) and 4 ms-1 air speed to study various drying phenomena above fibre saturation point. While drying, an X-ray computed tomography (CT) scanner captured a cross-cut density image every ten minutes. The density data was used to determine moisture content, rate of moisture loss from the core, wetline (boundary line of the free water region) depth and cross-cut area of the wood pieces. Repeating patterns were observed, which indicated that the cavity-size distribution of the wood pieces dictated fluctuations in the rate of moisture loss from the core and cross-cut area shrinkage during drying in the free water phase. It is hypothesised that, while drying an interconnected capillary network in the free water phase, the largest meniscus penetrates a wood piece through the largest cavities, thus also allowing air into the capillary network. The largest meniscus would always get smaller as it penetrates the wood piece until it is not the largest meniscus in the network anymore. Then the new largest meniscus would start penetrating the capillary network, etc. The largest meniscus would also determine the liquid tension in the capillary network. When the largest meniscus gets small enough, and the liquid tension strong enough, deformation and collapse of the remaining liquid-filled cavities can occur. A large liquid-filled interconnected capillary network would eventually fragment into a number of smaller liquid-filled interconnected networks, at which point a receding wetline could be observed. 相似文献