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排序方式: 共有1463条查询结果,搜索用时 585 毫秒
61.
Fabio LicciardelloPierangelo Frisullo Janine LaverseGiuseppe Muratore Matteo Alessandro Del Nobile 《Journal of food engineering》2012,108(3):453-462
Meringues are characterized by a predominant air phase and their overall quality is intimately related with microstructure. The formation of meringues microstructure relies on the capacity of egg white (EW) proteins to form voluminous and stable foams and it is ultimately related with the chemical properties of proteins and with the addition of ingredients such as sugars, salts, acids and surfactants.The study aimed at assessing the influence of sugar/EW ratio, citric acid and EW type on the microstructural and mechanical properties of meringues. Meringues prepared with different sugar/EW, citric acid level and different EW type were subjected to microstructural analysis by X-ray microtomography and to mechanical assessment by compression tests.Results demonstrate the ability of X-ray microtomography to reconstruct the 3D microstructure of meringues allowing the measurement of porosity, size, shape and distribution of pores. Citric acid, sugar concentration and EW type play a fundamental role on meringues microstructural parameters and mechanical properties. Low sugar/EW ratios as well as increasing citric acid levels increase the air phase and result in a softer texture of meringues. Moreover, low sugar/EW ratios and increasing citric acid in the meringue result in a reduction of pore size and also influence the shape of pores. Meringues microstructural and mechanical properties are affected by the EW quality: fresh and pasteurized EWs and EWs stored at refrigerated temperatures scored the highest structural and mechanical performances, while powdered and frozen EWs and albumens from old eggs showed the worst results. Not only the balance among ingredients but also the choice of raw materials can strongly affect the final quality of meringues. 相似文献
62.
Annalisa Lucera Amalia Conte Matteo Alessandro Del Nobile 《International Journal of Food Science & Technology》2012,47(8):1598-1604
In this work, the influence of packaging mass transport properties on quality loss of fresh‐cut cauliflower mixtures was addressed. The study was organised in two subsequent experimental steps; first, the selection of micro‐perforated packaging films was carried out by monitoring the package headspace gas concentrations of fresh‐cut white, green cauliflower and roman cabbage. Then, the effects of the barrier properties of the selected micro‐perforated film on shelf life of two different fresh‐cut cauliflower mixtures, stored at 4 ± 1 °C, were addressed. Results suggested that, among the investigated films, the micro‐perforated polymeric matrix with the lowest oxygen transmission rate value showed the best performance as it created the optimum headspace gas composition for each cauliflower variety, as well as, for the product mixtures. The appearance of visible moulds was the factor limiting product shelf life that accounted for about 18 days for both the investigated cauliflower mixtures. 相似文献
63.
Eduardo Di Mauro Matteo Camaggi Nils Vandooren Caleb Bayard Jordan De Angelis Alessandro Pezzella Bill Baloukas Richard Silverwood Abdellah Ajji Christian Pellerin Clara Santato 《Polymer International》2019,68(5):984-991
In the human body, the black‐brown biopigment eumelanin blocks harmful ultraviolet (UV) radiation. In the plastics industry, additives are often added to polymers to increase their UV‐absorption properties. We herein report an assessment of the biopigment eumelanin as a nature‐inspired additive for plastics to enhance their UV absorption. Since eumelanin is produced by natural sources and is nontoxic, it is an interesting candidate in the field of sustainable plastic additives. In this work, the eumelanin‐containing films of commercial ethylene–vinyl acetate copolymer, a plastic used for packaging applications, were obtained by melt compounding and compression molding. The biopigment dispersion in the films was improved by means of the melanin free acid treatment. It was observed that eumelanin amounts as low as 0.8 wt% caused an increase of the UV absorption, up to one order of magnitude in the UVA range. We also evaluated the effect of eumelanin on the thermal stability and photostability of the films: the biopigment proved to be double‐edged, working both as UV‐absorption enhancer and photo‐prooxidant, as thermogravimetric analysis and infrared spectroscopy revealed. © 2019 Society of Chemical Industry 相似文献
64.
Matteo Vasirani Sascha Ossowski 《Engineering Applications of Artificial Intelligence》2013,26(3):1185-1197
The near-future penetration of plug-in electric vehicles is expected to be large enough to have a significant impact on the power grid. If PEVs were allowed to charge simultaneously at the maximum power rate, the distribution grid would face serious problems of stability. Therefore, mechanisms are needed to coordinate various PEVs that charge simultaneously. In this paper we propose an allocation mechanism that aims at balancing allocative efficiency and fairness, providing preferential treatment to the PEVs that have a high valuation of the available power, while guaranteeing a fair share of this power to all thePEVs. 相似文献
65.
Juice and by-products from pomegranate to enrich pancake: characterisation and shelf-life evaluation
Anna Lucia Incoronato Annamaria Cedola Amalia Conte Matteo Alessandro Del Nobile 《International Journal of Food Science & Technology》2021,56(6):2886-2894
In this study, a fortified pancake with all parts of pomegranate as juice and by-products, added in the formulation, was designed. The influence of pomegranate addition on nutritional and sensory quality of pancake, as well as on its shelf-life, was assessed. As one would expect, the enrichment significantly improved the pancake polyphenolic content as compared to the control sample. Surprisingly, pomegranate addition did not affect its sensory quality. In fact, the enriched pancake was greatly appreciated from the sensory point of view. Results also suggested that the addition of pomegranate improved the glycemic index (GI). In fact, while a value of GI equal to 100 was obtained for the control sample, a GI of 71 was measured for the fortified sample. In terms of shelf-life, 30 days were obtained for the enriched pancake, whereas the control sample remained acceptable for about 26 days. 相似文献
66.
Matteo Palpacelli Giacomo Palmieri Luca Carbonari David Corinaldi 《Journal of Intelligent and Robotic Systems》2018,91(2):155-163
This paper is focused on the development and validation of an error kinematic model of a mini spherical robot, aimed at its kinematic calibration. The robot is actually a spatial five-bar linkage, provided with two rotational degrees of freedom. A non-overconstrained kinematics is assumed for the robot in order to provide a simple mathematical model and allow a sensitivity analysis of all the involved geometric parameters. A simplified version of the model is proposed. It differs only for the degree of approximation. A comparison between full and reduced models is presented by means of numerical simulations, analyzing their behavior in a significant region of the robot workspace. In order to validate both of them a robot calibration is carried out on a physical prototype of the robot using a vision system, namely a fixed camera in a eye-to-hand configuration. An iterative algorithm aimed at the experimental identification of the geometric data of the robot is used. Some experimental results show the effectiveness of the study. 相似文献
67.
68.
Pedrini Matteo Langella Valentina Battaglia Mario Alberto Zaratin Paola 《Scientometrics》2018,114(3):1227-1250
Scientometrics - In recent year, a growing attention is dedicated to the assessment of research’s social impact. While prior research has often dealt with results of research, the last decade... 相似文献
69.
Yuan Yu Matteo Cagnoni Oana Cojocaru‐Mirdin Matthias Wuttig 《Advanced functional materials》2020,30(8)
Thermoelectric materials have attracted significant research interest in recent decades due to their promising application potential in interconverting heat and electricity. Unfortunately, the strong coupling between the material parameters that determine thermoelectric efficiency, i.e., the Seebeck coefficient, electrical conductivity, and thermal conductivity, complicates the optimization of thermoelectric energy converters. Main‐group chalcogenides provide a rich playground to alleviate the interdependence of these parameters. Interestingly, only a subgroup of octahedrally coordinated chalcogenides possesses good thermoelectric properties. This subgroup is also characterized by other outstanding characteristics suggestive of an exceptional bonding mechanism, which has been coined metavalent bonding. This conclusion is further supported by a map that separates different bonding mechanisms. In this map, all octahedrally coordinated chalcogenides with good performance as thermoelectrics are located in a well‐defined region, implying that the map can be utilized to identify novel thermoelectrics. To unravel the correlation between chemical bonding mechanism and good thermoelectric properties, the consequences of this unusual bonding mechanism on the band structure are analyzed. It is shown that features such as band degeneracy and band anisotropy are typical for this bonding mechanism, as is the low lattice thermal conductivity. This fundamental understanding, in turn, guides the rational materials design for improved thermoelectric performance by tailoring the chemical bonding mechanism. 相似文献
70.