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排序方式: 共有384条查询结果,搜索用时 15 毫秒
41.
Nicolas Terrade Ronan Noël Romain Couillaud Ramón Mira de Orduña 《Food research international (Ottawa, Ont.)》2009,42(3):363-367
Growth and activity of lactic acid bacteria is crucial for the production and quality of grape wines but studying their metabolism is difficult in wines or complex laboratory media because of the undefined substrate pools. This work presents a new chemically defined medium that meets the fastidious nutritional requirements of wine lactic acid bacteria and yields rapid and strong growth. The new medium is composed of 44 constituents and a precise protocol is provided for its preparation. Maximum specific growth rates and growth yields of the wine strains studied were comparable to those obtained in common laboratory media, and the new medium allows for various modifications, such as changing the medium pH to the wine range, addition of L-malic acid or utilization of different carbon sources while maintaining growth of wine lactic acid bacteria. The medium was successfully tested with 22 wine strains of the genera Oenococcus, Lactobacillus and Pediococcus. It is suggested that this chemically defined medium be considered for the investigation of the nutritional requirements and metabolism of wine lactic acid bacteria. 相似文献
42.
43.
Romain Gautier Florian Massuyeau Gabin Galnon Michael Paris 《Advanced materials (Deerfield Beach, Fla.)》2019,31(14)
Hybrid metal halides containing perovskite layers have recently shown great potential for applications in solar cells and light‐emitting diodes. Such compounds exhibit quantum confinement effects leading to tunable optical and electronic properties. Thus, broadband white‐light emission has been observed from diverse metal halides and, owing to high color rendering index, high thermal stability, and low‐temperature solution processability, these materials have attracted interest for application in solid‐state lighting. However, the reported quantum yields for white photoluminescence (PLQY) remain low (i.e., in the range 0.5–9%) and no approach has shown to successfully increase the intensity of this emission. Here, it is demonstrated that the quantum efficiencies of hybrid metal halides can be greatly enhanced if they contain a polymorph of the [PbX4]2? perovskite‐type layers: the [PbX4]2? post‐perovskite‐type chains showing a PLQY of 45%. Different piperazines lead to a hybrid lead halide with either perovskite layers or post‐perovskite chains influencing strongly the presence of self‐trapped states for excitons. It is anticipated that this family of hybrid lead halide materials could enhance all the properties requiring the stabilization of trapped excitons. 相似文献
44.
[4]Helicene–Squalene Fluorescent Nanoassemblies for Specific Targeting of Mitochondria in Live‐Cell Imaging 下载免费PDF全文
Andrej Babič Simon Pascal Romain Duwald Dimitri Moreau Jérôme Lacour Eric Allémann 《Advanced functional materials》2017,27(33)
Ester, amide, and directly linked composites of squalene and cationic diaza [4]helicenes 1 are readily prepared. These lipid‐dye constructs 2 , 3 , and 4 give in aqueous media monodispersed spherical nanoassemblies around 100–130 nm in diameter with excellent stability for several months. Racemic and enantiopure nanoassemblies of compound 2 are fully characterized, including by transmission electron microscope and cryogenic transmission electron microscope imaging that did not reveal higher order supramolecular structures. Investigations of their (chir)optical properties show red absorption maxima ≈600 nm and red fluorescence spanning up to the near‐infrared region, with average Stokes shifts of 1350–1550 cm?1. Live‐cell imaging by confocal microscopy reveals rapid internalization on the minute time scale and organelle‐specific accumulation. Colocalization with MitoTracker in several cancer cell lines demonstrates a specific staining of mitochondria by the [4]helicene–squalene nanoassemblies. To our knowledge, it is the first report of a subcellular targeting by squalene‐based nanoassemblies. 相似文献
45.
This paper presents the abstraction of open consensus and argues for its use as an effective component for building reliable agreement protocols in practical asynchronous systems where processes and links can crash and recover. The specification of open consensus has a decoupled, on‐demand and re‐entrant flavour that make its use very efficient, especially in terms of forced logs, which are known to be major sources of overhead in distributed systems. We illustrate the use of open consensus as a basic building block to develop a modular, yet efficient, total‐order broadcast protocol. Finally, we describe our Java implementation of our open‐consensus abstraction and we convey our efficiency claims through some practical performance measures. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
46.
Denis Lapalme Romain Lemaire Patrice Seers 《International Journal of Hydrogen Energy》2017,42(12):8314-8328
This paper investigates the various techniques used in the literature to calculate the effective Lewis number of two-component (H2/CO and H2/CH4) and three-component fuels (H2/CO/CH4 and H2/CO/CO2) over a wide range of equivalence ratios (0.6 ≤ φ ≤ 1.4) under laminar flame conditions. The most appropriate effective Lewis number formulation is identified through comparison with experimentally extracted Lewis numbers (Le). The paper first identifies the proper methodology to extract the experimental Le from the burned Markstein length of an outwardly propagating flame. Second, the different methodologies for the calculation of the effective Le are presented and compared to experimental results for H2/CH4 and H2/CO mixtures. Based on the experimental results, it is shown that the calculation of the effective Le of mixtures can be divided into a three-step procedure depending on the equivalence ratio: (1) calculation of the Le for each fuel and the oxidizer; (2) use of the Le mixing rule; and (3) assessment of the necessity or not of combining the fuel's and oxidizer's Lewis numbers. The paper shows that, in rich mixtures, the oxidizer Le needs to be taken into account. Lastly, the methodology is validated for H2/CO/CH4 and H2/CO/CO2 fuels. 相似文献
47.
48.
Romain Sainte Beuve Ken R. Morison 《Chemical Engineering and Processing: Process Intensification》2010
A hydrodynamic cavitation system based on a venturi was used to test the effectiveness of cavitation for enhancing the enzymatic hydrolysis of canola oil using lipase from Candida rugosa. Cavitation led to the production of fine oil-in-water and water-in-oil emulsions with the enzyme in the water phase. Using venturi inlet pressures of up to 8 bar, the yield of fatty acids was only about 60% of the maximum possible. In contrast, a simple stirred batch reactor produced over 90% of the maximum possible yield with reaction rates equal to, or better than, those obtained in a cavitating system. It was concluded that cavitation inhibited the reaction in some way and is not effective for intensification of hydrolysis. 相似文献
49.
Romain Fillières Bouchra Benjelloun-Mlayah Michel Delmas 《Journal of the American Oil Chemists' Society》1995,72(4):427-432
High-performance size-exclusion chromatography (HPSEC) was used to evaluate the influence of different variables affecting
the transesterification of rapeseed oil (RSO) with anhydrous ethanol and sodium ethoxide as catalyst. The effect of temperature,
ethanol/RSO molar ratio, catalyst concentration, and time can be interpreted by observing the variations of the reaction medium
composition. HPSEC has made the quantitation of ethyl esters, mono-, di-, and triglycerides and glycerol possible. The best
results for laboratory-scale reactions were obtained at 80°C with a 6:1 molar ratio of EtOH/RSO and 1% of NaOEt by weight
of RSO. 相似文献
50.
Recent planar technologies with 3 metal layers or more challenge current physical design modification capacities using Focused Ion Beam tools. Image visibility on the FIB is drastically reduced, making accurate positioning and milling operations in the area of interest more difficult. Despite the complexity of FIB modifications, however, the demand for circuit modifications continues to increase. We will present a method which brings voltage contrast measurement capabilities to FIB systems. With this method, it is possible to verify the completion of FIB repairs. 相似文献