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51.
Since the advent of the World Wide Web, online media archives have changed their audience from a restricted number of professionals and amateurs to the general public. This shift is not without consequences: if, on the one side, it represents an important opportunity for archives to engage in a dialogue with a larger audience, on the other side, it advocates novel forms of access that go beyond the highly specialized models underlying traditional access tools. In this paper, we propose to use 3-D graphics for designing novel tools of exploratory search in cultural heritage archives. Our approach has been deployed as an online virtual environment where the user can navigate the meaning relations over the items in the archive. Targeted at cultural heritage, the application, called Labyrinth 3D, relies on the use of cultural archetypes to inform the conceptualization of the archive and the creation of the virtual environment, with the goal of engaging the user in the exploration of the archive through the creation of personal paths. 相似文献
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Binary boundary maps are obtained by edge detection, then their relative translation is determined by conventional cross-correlation computed by the Fermat transform. Use of boundary maps emphasises edges and sharp discontinuities, while rejecting disturbances related to nonuniform illumination, thus avoiding the costly normalisation step. Use of integer arithmetic allows significant savings in computation 相似文献
54.
Digital image registration using projections 总被引:3,自引:0,他引:3
Alliney S Morandi C 《IEEE transactions on pattern analysis and machine intelligence》1986,(2):222-233
In many application fields (e.g., aerospace and biomedical image processing), one has to deal with a sequence of images whose observation is made difficult by unpredictable relative movements of the camera and the scene. In order to obtain a stable display, the displacement of each image in the sequence with respect to one chosen as a reference must be preliminarily determined. This would usually require two-dimensional algorithms, involving a considerable computational effort. This work discusses a new algorithm for image registration, which requires only one-dimensional Fourier transformations. Preliminary experimental results are reported. 相似文献
55.
A miniature electrostatic element has been designed to selectively apply a 90 degrees phase shift to the unscattered beam in the back focal plane of the objective lens, in order to realize Zernike-type, in-focus phase contrast in an electron microscope. The design involves a cylindrically shaped, biased-voltage electrode, which is surrounded by a concentric grounded electrode. Electrostatic calculations have been used to determine that the fringing fields in the region of the scattered electron beams will cause a negligible phase shift as long as the ratio of electrode length to the transverse feature size is greater than 5:1. Unlike the planar, three-electrode einzel lens originally proposed by Boersch for the same purpose, this new design does not require insulating layers to separate the biased and grounded electrodes, and it can thus be produced by a very simple microfabrication process. Scanning electron microscope images confirm that mechanically robust devices with feature sizes of approximately 1 microm can be easily fabricated. Preliminary experimental images demonstrate that these devices do apply a 90 degrees phase shift between the scattered and unscattered electrons, as expected. 相似文献
56.
U Morandi A Stefani M Golinelli C Ruggiero L Brandi A Chiapponi C Santi R Lodi 《Canadian Metallurgical Quarterly》1997,11(3):432-439
Calcium release from the sarcoplasmic reticulum (SR) depending on depolarization of the transverse tubular membrane (TTM) caused by rapid ionic replacement was measured in skeletal muscle triadic vesicles using a stopped-flow apparatus and Fura-2, a membrane-impermeable Ca2+ indicator. Calcium release was triggered by an increase in the magnitude of depolarization. This Ca2+ release was inhibited by ruthenium red, digoxin and dantrolene, and enhanced by caffeine. Thus, Ca2+ release was found to occur through the SR Ca2+ release channel via TTM depolarization and to be able to cause skeletal muscle contraction. Calcium release curves could be divided into two phases. In contrast to other previous studies, in the fast phase the amount of released Ca2+ increased with an increase in the magnitude of depolarization but the Ca2+ release rate did not; on the other hand, in the slow phase the Ca2+ release rate increased but the amount of Ca2+ did not. Furthermore, the Ca2+ release rate was controlled by the luminal Ca2+ concentration of the SR only in the fast phase. These independent dual kinetics of Ca2+ release were explained by the calsequestrin regulation model. 相似文献
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Use of sourdough fermented wheat germ for enhancing the nutritional, texture and sensory characteristics of the white bread 总被引:3,自引:1,他引:3
Carlo Giuseppe Rizzello Luana Nionelli Rossana Coda Raffaella Di Cagno Marco Gobbetti 《European Food Research and Technology》2010,230(4):645-654
Lactobacillus plantarum LB1 and Lactobacillus rossiae LB5, isolated from wheat germ and selected based on the kinetics of acidification, were used as starters for the manufacture
of sourdough fermented wheat germ. A bread containing sourdough fermented wheat germ as an ingredient (SFWGB) was compared
to breads made with (raw wheat germ bread, RWGB) or without (wheat flour bread, WFB) raw wheat germ. The higher concentration
of free amino acids mainly differentiated SFWGB from WFB and RWGB. The in vitro protein digestibility of WFB was the highest,
even if sourdough fermentation of wheat germ attenuated the difference. Phytase and antioxidant activities of SFWGB were highest.
The specific volume and cell-total areas were also the highest for SFWGB. As determined by texture profile analysis, the values
of hardness, resilience and fracturability of breads containing wheat germ were lower than those found in WFB. The crust lightness
showed a decrease from WFB to SFWGB. As determined by sensory analysis, SFWGB had mainly acid taste and flavour and resulted
more salty. Sourdough fermented wheat germ is an ingredient able to enhance nutritional, texture and sensory properties of
bread. 相似文献
59.
Roberta Papagni Carmen Pellegrino Francesco Di Gennaro Giulia Patti Aurelia Ricciardi Roberta Novara Sergio Cotugno Maria Musso Giacomo Guido Luigi Ronga Stefania Stolfa Davide Fiore Bavaro Federica Romanelli Valentina Totaro Rossana Lattanzio Giuseppina De Iaco Fabrizio Palmieri Annalisa Saracino Gina Gualano 《International journal of molecular sciences》2022,23(7)
Vitamin D plays a crucial role in many infectious diseases, such as tuberculosis (TB), that remains one of the world’s top infectious killers with 1.5 million deaths from TB in 2021. Vitamin D suppresses the replication of Mycobacterium tuberculosis in vitro and showed a promising role in TB management as a result of its connection with oxidative balance. Our review encourages the possible in vivo benefit of a joint administration with other vitamins, such as vitamin A, which share a known antimycobacterial action with vitamin D. However, considering the low incidence of side effects even at high dosages and its low cost, it would be advisable to assess vitamin D level both in patients with active TB and high-risk groups and administer it, at least to reach sufficiency levels. 相似文献
60.