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991.
S. Kuriyama Y. Yoshida T. Takahashi S. Kumagaya T. Aoki K. Miyauchi 《Journal of Materials Processing Technology》2003,140(1-3):13-18
A code of FEM for an elastic and plastic material has been developed to calculate a residual stress distribution in D-I can by both-sided ironing. It is possible for the code to simulate a forming process of deep drawing from a sheet to a can, an ironing process of both-sided of the can wall, and a deformation of the whole of the can under perfect unloading when the can is removed from an equipment of deep drawing and ironing. From these simulations, quite different and contrary distributions of residual stress are obtained according to mutual positions of dies for the ironing, which are considered to expand the wall of can as an ellipsoidal shape or shrink it to a hyperbolic shape. 相似文献
992.
A qualitative design was used to explore Italo-Canadian beliefs about the cause and treatment/cure of childhood disabilities. A convenience sample of eight second-generation Italo-Canadian mothers of children with moderate to severe disabilities was recruited through a pediatric rehabilitation centre in Southern Ontario. The mothers were interviewed using open-ended questions that served as probes to stimulate their thoughts and feelings. Data analysis proceeded concomitantly with data collection, and consisted of content analysis. Three major categories of traditional causation beliefs were identified: (a) punishment for past wrongdoing, (b) "bad blood" caused by intermarriage or a family curse, and (c) supernatural forces such as mal'occhio (the evil eye). The major category identified for cure of childhood disability was magico-religious healing. These traditional beliefs were described by the mothers to be strongest among first-generation Italo-Canadians, especially grandparents. The mothers themselves expressed their acceptance of some of these beliefs, but only minimal acceptance of or resistance to others. Based on this study, it would be premature to formulate implications for practice; however, several directions for future research are identified. 相似文献
993.
S Nakagawa S Kurata A Yoshida Y Nagase M Moritani M Takemura YC Bae Y Shigenaga 《Canadian Metallurgical Quarterly》1997,389(1):12-33
Previous work suggests that slowly adapting (SA) periodontal afferents have different synaptic arrangements in the principal (Vp) and oral trigeminal nuclei and that the synaptic structure associated with transmitter release may be related directly to bouton size. The present study examined the ultrastructures of SA and fast adapting (FA) vibrissa afferents and their associated unlabeled axonal endings in the cat Vp by using intra-axonal labeling with horseradish peroxidase and a morphometric analysis. All SA and FA afferent boutons contained clear, round, synaptic vesicles. All the FA and most SA boutons were presynaptic to dendrites, but a few SA boutons were axosomatic. Both types of bouton were frequently postsynaptic to unlabeled axonal ending(s) containing pleomorphic, synaptic vesicles (P-ending). The size of labeled boutons was larger in FA than SA afferents, but the size of dendrites postsynaptic to labeled boutons was larger for SA than FA afferents. Large-sized FA and SA boutons made synaptic contacts with small-diameter dendrites. The size of FA and SA boutons was larger than that of their associated P-endings. A morphometric analysis made on the pooled data of SA and FA boutons indicated that apposed surface area, active zone number, total active zone area, vesicle number, and mitochondrial volume were highly correlated in a positive linear manner with labeled bouton volume. These relationships were also applicable to unlabeled P-endings, but the range of each parameter was smaller than that of the labeled boutons. These observations provide evidence that the two functionally distinct types of vibrissa afferent manifest unique differences but share certain structural features in the synaptic organization and that the ultrastructural "size principle" proposed by Pierce and Mendell ([1993] J. Neurosci. 13:4748-4763) for Ia-motoneuron synapses is applicable to the somatosensory system. 相似文献
994.
N Miyazono K Ueno M Nakajo H Nishida H Inoue S Tsuchimochi H Hokotate H Yoshida 《Canadian Metallurgical Quarterly》1996,31(12):755-760
RATIONALE AND OBJECTIVES: The authors compared the embolic effect of radiolucent absolute ethanol (AE) with that of a radiopaque iohexol-ethanol (IES) solution for renal ablation in dogs and for the destruction of human aldosteronomas by the technique of transcatheter arterial embolization (TAE) to test whether IES can be an alternative to AE. METHODS: The embolic agents were infused through a balloon catheter into the renal arteries of 17 dogs (9 infused with 0.3 mL/kg AE; 8 infused with IES). The immediate and parenchyma were compared between the two groups. Transcatheter arterial embolization with IES also was performed in three humans with unilateral aldosteronoma. RESULTS: The IES was visualized faintly under fluoroscopy in all dogs. There were no significant differences in embolic effects between the AE and IES. Three patients with aldosteronoma were treated successfully by TAE with IES. CONCLUSIONS: The IES can be used as a "visible ethanol" to improve the safety and ease of ethanol embolization. 相似文献
995.
Nagata S Tsuneta S Sakao T Yoshida T Hara H Kano R Ishiyama W Murakami K Ohtan M 《Applied optics》1997,36(13):2830-2838
Multilayer mirrors with a system wavelength resolution (lambda/Dlambda) as high as 30-50 are required for the diagnostics of cosmic plasmas with temperatures of 1-20 MK. Such a high wavelength resolution can be realized by increasing the number of layer pairs contributing to the reflectance, by selecting less-absorbing materials for both the reflector and the spacer, and by decreasing the thickness of the reflector. We have fabricated a multilayer mirror tuned to 284 A with a silicon carbide reflector (20% thickness of the layer period) and an aluminum spacer and achieved lambda/Dlambda ~26.8 with a peak reflectivity of ~13.0%. This wavelength resolution is close to the value obtained with a numerical simulation and is considerably higher than the value obtained with the conventional Mo/Si multilayer. 相似文献
996.
The general behavior of two-photon absorption-enhanced refractive-index change in a third-order nonlinear optical medium is briefly described. The nonlinear medium was the solution of a new dye, trans-4-[p-(N-hydroxyethyl-N-methylamino)styryl]-N-methyl pyridinium iodide (ASPI) in dimethyl sulfoxide as the solvent, that was poured into a 20-cm-long quartz hollow fiber of 100-mum internal diameter. This dye solution has a strong two-photon absorption and subsequent upconversion fluorescence emission when excited with 1064-nm laser radiation. When the input peak intensity reached 500-1500-MW/cm(2) levels, obvious changes in beam profiles of the output IR laser beam were observed due to a self-focusing or self-trapping process occurring inside the fiber system. As a result of this process, highly directional frequency-upconverted superradiant lasing output was obtained with a beam size ~5 times smaller than that of a linearly transmitted He-Ne probe laser beam. The demonstrated mechanism can be useful for fiber laser-amplifier and fiber-integrated optics devices. 相似文献
997.
998.
Microsystem Technologies - An optical sensor, such as a light waveguide implemented total analysis system (TAS), is one of the functional components that will be needed to realize a... 相似文献
999.
Rhombic‐Shaped Nanostructures and Mechanical Properties of 2D DNA Origami Constructed with Different Crossover/Nick Designs 下载免费PDF全文
Zhipeng Ma Yunfei Huang Seongsu Park Kentaro Kawai Do‐Nyun Kim Yoshikazu Hirai Toshiyuki Tsuchiya Hirofumi Yamada Osamu Tabata 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(1)
DNA origami methods enable the fabrication of various nanostructures and nanodevices, but their effective use depends on an understanding of their structural and mechanical properties and the effects of basic structural features. Frequency‐modulation atomic force microscopy is introduced to directly characterize, in aqueous solution, the crossover regions of sets of 2D DNA origami based on different crossover/nick designs. Rhombic‐shaped nanostructures formed under the influence of flexible crossovers placed between DNA helices are observed in DNA origami incorporating crossovers every 3, 4, or 6 DNA turns. The bending rigidity of crossovers is determined to be only one‐third of that of the DNA helix, based on interhelical electrostatic forces reported elsewhere, and the measured pitches of the 3‐turn crossover design rhombic‐shaped nanostructures undergoing negligible bending. To evaluate the robustness of their structural integrity, they are intentionally and simultaneously stressed using force‐controlled atomic force microscopy. DNA crossovers are verified to have a stabilizing effect on the structural robustness, while the nicks have an opposite effect. The structural and mechanical properties of DNA origami and the effects of crossovers and nicks revealed in this paper can provide information essential for the design of versatile DNA origami structures that exhibit specified and desirable properties. 相似文献
1000.
Kentaro Yaji Masaki Otomori Takayuki Yamada Kazuhiro Izui Shinji Nishiwaki Olivier Pironneau 《Structural and Multidisciplinary Optimization》2016,54(3):659-672
The aim of this research is to construct a shape optimization method based on the convected level set method, in which the level set function is defined as a truncated smooth function obtained by using a sinus filter based on a hyperbolic tangent function. The local property of the hyperbolic tangent function dramatically reduces the generation of red the error between the specified profile of the hyperbolic tangent function and the level set function that is updated using a time evolution equation. In addition, the small size of the error facilitates the use of convective reinitialization, whose basic idea is that the reinitialization is embedded in the time evolution equation, whereas such treatment is typically conducted in a separate calculation in conventional level set methods. The convected level set method can completely avoid the need for additional calculations when performing reinitialization. The validity and effectiveness of our presented method are tested with a mean compliance minimization problem and a problem for the design of a compliant mechanism. 相似文献