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51.
Fibres are subjected to forces while undergoing drafting in any drafting zone. Various factors, such as fibre bulk, roller setting, roller pressure, draft, fibre length, fineness and friction between fibres, affect the magnitude of this force. It is usually considered that the drafting force in the ring frame is too low to have any consequence as far as fibre breakage is concerned. The present investigation, however, shows a substantial increase in short fibre percentage and reduction in upper quartile length, giving a clear evidence of fibre breakage during drafting process. 相似文献
52.
Polymer dispersed ferroelectric liquid crystal composite films consisting of varying polymer viscosities were prepared by polymerization induced phase separation (PIPS) technique. It was found that polymer viscosity influences the polarization switching and optical responses. A polymer dispersed ferroelectric liquid crystal film of low polymer viscosity shows faster switching, however a higher optical transmission at ~ 70% was observed in a higher polymer viscosity film. 相似文献
53.
Text characters embedded in images represent a rich source of information for content-based indexing and retrieval applications. However, these text characters are difficult to be detected and recognized due to their various sizes, grayscale values, and complex backgrounds. Existing methods cannot handle well those texts with different contrast or embedded in a complex image background. In this paper, a set of sequential algorithms for text extraction and enhancement of image using cellular automata are proposed. The image enhancement includes gray level, contrast manipulation, edge detection, and filtering. First, it applies edge detection and uses a threshold to filter out for low-contrast text and simplify complex background of high-contrast text from binary image. The proposed algorithm is simple and easy to use and requires only a sample texture binary image as an input. It generates textures with perceived quality, better than those proposed by earlier published techniques. The performance of our method is demonstrated by presenting experimental results for a set of text based binary images. The quality of thresholding is assessed using the precision and recall analysis of the resultant text in the binary image. 相似文献
54.
M.K. Raina 《Creativity & Innovation Management》1996,5(3):149-150
With grateful acknowledgement to a prepublication release by Georgia Studies of Creative Behavior (1994). 相似文献
55.
Results obtained on characterization of lanthanum tartrate crystals, grown by the gel method, using chemical analysis, x-ray
and electron diffraction, infra-red and mass spectroscopy are reported. The thermal behaviour is studied using DTA, TGA and
DTG. The decomposition pattern is reported to be typical of a hydrated metal tartrate. Kinetic parameters like order of reaction,
frequency factor and activation energy are evaluated. Contracting cylinder kinetic model is found to be the best fit for the
decomposition processes involved. Magnetic susceptibility measurements indicate the material to be diamagnetic. 相似文献
56.
57.
A theoretical expression has been presented for the prediction of the instantaneous heat transfer coefficient of a condensing two-phase bubble. The modified form of this model predicts very well the available experimental data. Another expression, presented for the total time taken by an evaporating two-phase drop, also gives very good agreement with the available experimental data. 相似文献
58.
59.
The spherulitic, dendritic and single-crystal growth of hydrated lanthanum tartrate by controlled diffusion in silica gels is reported. The influence of growth parameters, e.g. reactant concentrations, gel pH, gel ageing, on the size and nucleation density of crystals has been studied. Operative mechanisms of crystallization, results of growth kinetics and morphology of crystals are discussed. The adsorption property of the gel is found to play a vital role during the crystallization of lanthanum tartrate crystals, Parabolic kinetics, characteristic of a one-dimensional diffusion-controlled process, for single crystals is observed to be obeyed in case of variation of upper reactant concentration. 相似文献
60.
Fernando Soto Miguel Angel Lopez‐Ramirez Itthipon Jeerapan Berta Esteban‐Fernandez de Avila Rupesh Kumar Mishra Xiaolong Lu Ingrid Chai Chuanrui Chen Daniel Kupor Amir Nourhani Joseph Wang 《Advanced functional materials》2019,29(22)
Self‐propelled biohybrid microrobots, employing marine rotifers as their engine, named “rotibot,” are presented and their practical utility and advantages for environmental remediation are demonstrated. Functionalized microbeads are attached electrostatically within the rotifer mouth and aggregated inside their inner lip. The high fluid flow toward the mouth, generated by the strokes of rotifer cilia bands, forces an extremely efficient transport of the contaminated sample over the active surfaces of the functionalized microbeads. The reactive particles confined around the rotifer's lip are thus exposed to a high flow rate of the pollutant solution, resulting in dramatically accelerated decontamination processes, without external mixing or harmful fuels. Theoretical simulations, modeling the greatly enhanced fluid dynamic associated with such built‐in mixing effect, correlate well with the experimental observations. The rotibot thus proves to be an effective, versatile, and robust dynamic microcleaning platform for removing diverse environmental pollutants. Microbeads functionalized with lysozyme and organophosphorus hydrolase enzymes are shown to be extremely useful for enzymatic biodegradation of Escherichia coli and the nerve agent methyl paraoxon, respectively, while ligand (meso‐2,3‐dimercaptosuccinic acid) modified beads are used for removing heavy metal contaminants. Rotifer‐based biohybrid microrobots hold considerable promise as self‐propelling dynamic pumps for diverse large‐scale environmental remediation applications. 相似文献