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21.
Thick plasma sprayed thermal barrier coatings are suitable for thermal and hot corrosion protection of metal components in land-based turbine and diesel engines. In this work, ceria–yttria co-stabilized zirconia coatings were deposited by atmospheric plasma spraying in a mixture of non-transformable tetragonal t′ and cubic c zirconia phases. Free-standing coatings were isothermally annealed at 1315 °C for different times and their crystal structure was studied by XRD. No phase decomposition occurred. Columnar grains grew in the molten splats with increasing annealing time according to a preferential direction and, after 50 h of heat treatment, they were partially replaced by equiaxed grains. Both in-plane and out-of-plane thermal expansion coefficients (CTEs) were measured from coating expansion during heating. The CTE was slightly sensitive to thermal exposure in out-of-plane direction, whereas it kept almost constant in plane direction. The specific heat capacity Cp of annealed coatings, measured by differential scanning calorimetry (DSC), decreased in comparison with as-sprayed coating, due to high-temperature sintering. 相似文献
22.
Aseem Grover Reshma Sinha Divya Jyoti Caterina Faggio 《Microscopy research and technique》2022,85(5):1976-1989
Electron microscope (EM) was developed in 1931 and since then microscopical examination of both the biological and non-biological samples has been revolutionized. Modifications in electron microscopy techniques, such as scanning EM and transmission EM, have widened their applicability in the various sectors such as understanding of drug toxicity, development of mechanism, criminal site investigation, and characterization of the nano-molecule. The present review summarizes its role in important aspects such as toxicity assessment and disease diagnosis in special reference to SARS-COV2. In the biological system, EM studies have elucidated the impact of toxicants at the ultra-structural level in various tissue in conformity to physiological alterations. Thus, EM can be concluded as an important tool in toxicity assessment and disease prognosis. 相似文献
23.
Despite digital 3-D polygon modelling applications providing a common and powerful tool-set for archaeological, architectural and historical visualisation over recent years, the relatively recent developments in high-resolution sculpting software allow for the possibility to create digital outcomes with a degree of surface fidelity not previously obtainable from the more widely used poly-modelling software packages. Such digital sculpting applications are more commonly applied within the video games and TV/motion picture industries, the intention of this paper is to show how such tools and methodologies together with existing scanned data and some historical knowledge can remediate and re-imagine lost sculptural form. The intended research will focus on an examination and partial re-construction of the tomb of Sir John Neville, 3rd Baron Raby located at Durham Cathedral, County Durham UK. 相似文献
24.
Marzia Fontana Author Vitae Caterina Rizzi Author Vitae Author Vitae 《Computer aided design》2005,37(6):609-622
The integration of physics-based models within CAD systems for garment design leads to highly accurate cloth shape results for virtual prototyping and quality evaluation tasks. To this aim, we present a physics-based system for virtual cloth design and simulation expressly conceived for design purposes. This environment should allow the designer to validate her/his style and design option through the analysis of garment virtual prototypes and simulation results in order to reduce the number and role of physical prototypes. Garment shapes are accurately predicted by including material properties and external interactions through a particle-based cloth model embedded in constrained Newtonian dynamics with collision management, extended to complex-shaped assembled and finished garments. Our model is incorporated within a 3D graphical environment, and includes operators monitoring the whole design process of apparel, e.g. panel sewing, button/dart insertion, multi-layered fabric composition, garment finishings, etc. Applications and case studies are considered, with analysis of CAD modelling phases and simulation results concerning several male and female garments. 相似文献
25.
26.
Manes F De Santis F Giannini MA Vazzana C Capogna F Allegrini I 《The Science of the total environment》2003,308(1-3):133-141
An ozone monitoring network was set up using passive samplers and biological mini-stations of two clones of white clover (Trifolium repens L. cv. Regal), NC-R (O(3)-resistant) and NC-S (O(3)-sensitive). This paper reports on a pilot study performed in the period June-October 1999 in the Rome municipal area by using five biomonitoring mini-stations and ozone passive samplers with a new nitrite based design. This combined methodology can be used to obtain information on the biological implications of the injury due to tropospheric ozone. The two techniques can integrate data for the short-medium period and can be placed in different urban and rural sites, proving to be a very useful tool for ozone concentration mapping. 相似文献
27.
Online 3D Shared Spaces (3DSSs) can be regarded as a frontier of the Web 2.0, where users as participants contribute to create a meaningful, engaging experience. Like other complex web applications, the development and evolution
of high-quality 3DSS applications requires methodological support—through models, methods, and principles. Yet, the application
of structured, engineered approaches to this domain is largely unexplored. The purpose of this paper is to contribute to bridging
Web Engineering to the 3DSS world by means of design patterns. We present five patterns that focus on two factors deemed necessary for effective experiences in a 3DSS: Presence (i.e. the feeling of “being there”, typical of “virtual worlds”) and Long-Term Engagement (typical of successful Web 2.0 communities). The patterns presented in the paper distil our large-scale experiences with
3DSSs (that have involved so far over 9,000 youngsters from 3 continents) and are discussed in the light of existing literature. 相似文献
28.
In this paper, different arrangements of Kelvin–Voigt elements are implemented in an admittance matrix model to investigate the transient modeling of water distribution systems. The viscoelastic parameters are calibrated by experimental data acquired during a transient in a branched system of three HDPE pipes at the Water Engineering Laboratory of the University of Perugia, Italy. The dependence of the viscoelastic parameters on the branch characteristic time is investigated. Models with a single set of elements for all branches are compared with models with different sets of elements for each branch. When the same number of parameters is used, the former perform better than the latter. No evident correlation is found between the retardation times of the viscoelastic parameters and the branch characteristic times. The use of two measurement sections instead of one does not modify the calibration results significantly. 相似文献
29.
Isolation of red wine components with anti-adhesion and anti-biofilm activity against Streptococcus mutans 总被引:1,自引:0,他引:1
Maria Daglia Monica Stauder Adele Papetti Caterina Signoretto Giovanni Giusto Pietro Canepari Carla Pruzzo Gabriella Gazzani 《Food chemistry》2010
Red wine is a widely consumed beverage with multiple beneficial effects on human health. In the present paper, the anticaries properties of red wine were studied in vitro and ex vivo. Our in vitro findings shows that dealcoholised red wine, besides exerting antibacterial activity, strongly interferes with Streptococcus mutans adhesion to saliva-coated hydroxyapatite (sHA) beads, promotes its detachment from sHA, and powerfully inhibits in vitro biofilm formation. The main components responsible for such activities were found to be proanthocyanidins. The ability of red wine to inhibit ex vivoS. mutans biofilm formation on the occlusal surface of natural human teeth also was demonstrated. 相似文献
30.
Manuela Lasagna Caterina Caviglia Domenico Antonio De Luca 《Bulletin of Engineering Geology and the Environment》2014,73(2):341-355
The Maggiore Valley well field plays a fundamental role in supplying drinking water to a large territory of the Piedmont (north-western Italy). However, an increasing demand for water has led to the overexploitation of the groundwater resources. This situation has caused a progressive drawdown of the piezometric level (locally, up to 0.8 m/year), a spatial reduction in the artesian zone, localised land subsidence and damage to wells. The main purpose of this study was the development of a groundwater flow model of the area for analysing the aquifer response to various pumping strategies. Initially, the groundwater flow simulation (achieved by the application of the MODFLOW code) was calibrated satisfactorily. Then, the groundwater response to four scenarios was simulated to explore the best option to mitigate the problem. In three of the scenarios, a withdrawal reduction of 110 l/s was simulated, whilst considering various relocation options for extraction within the well field. The fourth scenario simulated a withdrawal reduction of 150 l/s; this option also assumed a supplementary water supply from the Monferrato Aqueduct, located north of the study area. All the simulations provided an increase in the piezometric level; in some instances, up to 30 m. Based on these simulations, the most promising management strategy for the Maggiore Valley well field would seem to be the option using a supplementary feed from the Monferrato Aqueduct. In this instance, the predicted piezometric level rise would be up to 25 m; this option also precludes the need for drilling additional wells. 相似文献