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71.
Carlos A. Montoya Jean-Paul Lallès Stephen Beebe Pascal Leterme 《Food research international (Ottawa, Ont.)》2010,43(2):443-449
This article proposes a new way to improve the protein quality of the common bean (Phaseolus vulgaris). It is based on the natural variability found in the different types of phaseolin, its main storage protein (40–50% of the total protein). Despite the fact that it is deficient in methionine content, phaseolin still represents the main source of that amino acid in the seed. More than 40 genetic variants, differing in subunit number (2–6) and molecular weight (40–54 kDa) have been analyzed. The similarity of the amino acid composition among phaseolins, suggests that a nutritional improvement cannot be expected from that side. Conversely, important variation in phaseolin susceptibility to proteolysis (ranging from 57% to 96% after cooking) has been observed, increasing the theoretical availability of methionine by up to 37%. Therefore, breeding programs based on highly-digestible phaseolin types could lead to the production of beans with higher protein quality. 相似文献
72.
Raphaël Faure Fabrice RossignolClaire Bonhomme Alexandre MaîtreGrégory Etchegoyen Pascal Del GalloDaniel Gary 《Journal of the European Ceramic Society》2011,31(3):303-312
The manufacture and the characterisation of alumina foams as alternative catalysts supports for industrial steam reforming processes are presented here. The possibility of use of alumina foams as catalysts supports in such processes is evaluated by studying their resistance toward mechanical and chemical stresses. The alumina foams produced are characterised owing to their processing parameters (slurry infiltration, sintering temperature, template pore size). Their ability to work in hydrothermal atmosphere is assessed by characterising the evolution of microstructures and mechanical strengths upon aging. Thermodynamic studies of the stability of alumina in industrial steam reforming working conditions are performed and correlated to the experiments to demonstrate the stability of such a system. 相似文献
73.
Mr. Alain Froment Mr. Pascal Gautier Mr. Alexandre Nussbaumer Mr. Alec Griffiths 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2011,6(2):277-281
Some mycotoxins are produced by several Fusarium species during cultivation and are found in wheat and maize grain. Since 2000, Syngenta has organised a large field survey. Agronomic and climatic data and grain samples have been collected for mycotoxin analysis in France and Belgium. The importance of the agroclimatic factors and their interactions on the mycotoxin levels in grain has been estimated. The climate around flowering stage is the major factor for deoxynivalenol (DON) in wheat. The main agronomic criteria are residue management and the variety sensitivity to this mycotoxin. For DON, zearalenone and fumonisins in maize, the climate from flowering stage until harvest is the major factor. Then, according to each mycotoxin, the main agronomic criteria are the harvest condition (date and grain moisture), the corn borer infestation and the variety sensitivity to these mycotoxins. Over the years, the database has been used to define models to predict the mycotoxin risk before harvesting. Grain purchasers enter the required agronomic data via the Syngenta Internet site and define their grain purchasing areas. They also define the flowering period for wheat and corn borer infestation for maize. After calculation which integrates climatic data, the purchasers receive reports with forecasts of mycotoxin levels. Prediction is based on different agro-climatic statistical models specifically configured according to the different regions of production in France and Belgium. This approach is called Qualimètre? and was the first service in France and Belgium to forecast the grain mycotoxin level for wheat in 2004 and maize in 2006. 相似文献
74.
Sébastien Griffon Amélie Nespoulous Jean-Paul Cheylan Pascal Marty Daniel Auclair 《Virtual Reality》2011,15(4):279-294
Although land managers and policy-makers generally have a good experience of what result can be expected from their decisions,
they are often faced with difficulty when trying to communicate the visual impact of a management option to stakeholders,
particularly when the landscape exhibits a high cultural value. Three-dimensional visualization of the landscape is often
used for communicating with the stakeholders. A challenge in participatory methods for integrated assessment and policy planning
is to view future changes in land use, according to scenarios. A 3-D landscape visualization component, SLE (“Seamless Landscape
Explorer”), has been developed, which is launched after a scenario simulation to allow for exploration of landscape changes.
Pressures causing such changes are translated into changes in the spatial configuration of the landscape. The different types
of land-use are visualized thanks to a library of detailed textures, and vegetation can be added. This has been applied to
a study of four scenarios in the French Mediterranean region, which were set up as part of a participatory process for discussing
the planning of the regional peri-urban and agricultural policy, in an area dominated by the typical culturally sensitive
Mediterranean matorral, (“garrigue” shrubland) surrounding the Pic Saint-Loup mountain. Examples of visualization are shown
and discussed here. 相似文献
75.
Ahmed Amine Rekik Florence Azaïs Norbert Dumas Frédérick Mailly Pascal Nouet 《Journal of Electronic Testing》2011,27(3):411-423
This paper presents a behavioral model that can be used to improve the manufacturability of systems based on MEMS convective
sensors. This model permits to handle faults related to process scattering, taking into account not only the electrical and
lateral geometrical parameters but also the influence of the cavity depth. Moreover correlations between conductive and convective
phenomena are included. The model is validated with respect to FEM simulations and a very good agreement is obtained between
the behavioral model and FEM results. The proposed model can then be used in system-level simulations, for instance to evaluate
the impact of process scattering on the performances of the sensing part and/or to investigate different design and calibration
strategies with respect to the system robustness. 相似文献
76.
77.
Edwina Klay Frédéric Diologent Johanne Arnéodo Pascal Dubos Andreas Mortensen 《Intermetallics》2011,19(5):726-737
Seven alloys of the ternary Au-Cu-Pt system, containing 75 or 76.5 wt.% Au with 0–15 wt.% Pt and heat-treated to a fully ordered condition, are examined using in-situ synchrotron radiation to determine transformation temperatures and phases formed, and to investigate mechanisms of ordering and disordering. These experiments are complemented by differential scanning calorimetry. Diffraction data show that the alloys can be separated into three groups according to their stable low-temperature ordered phase(s), namely L10, L12, or the two combined. Platinum increases transformation temperatures in comparison with binary AuCu, two-phase ordered alloys showing the highest transformation temperatures. Details of the evolution of the X-ray diffraction peak structures upon heating and cooling point to significant differences between mechanisms of disordering and ordering: whereas ordering visibly proceeds at significant undercooling by nucleation and growth, disordering appears, from the visible shifts in peak position, to progress in more homogeneous fashion within the alloy. 相似文献
78.
Dries Huygens Dries Roobroeck Lynn Cosyn Francisco Salazar Roberto Godoy Pascal Boeckx 《Nutrient Cycling in Agroecosystems》2011,89(2):175-187
The natural soil N supply in volcanic soils (Andisols) can be a significant source of plant-available N for agro-ecosystems.
Nevertheless, intensive farming systems in south Chile apply high fertilization rates, which lead to high production costs
and involve a risk for adverse ecosystem effects. In order to achieve sustainable land management, a better understanding
of the processes that govern soil N availability and loss, and their external drivers, is required. In this study, we selected
a winter-cropland, a summer crop-winter fallow rotation, and a forest, used as a reference ecosystem. Gross N transformations
(15N isotope dilution) and microbial community structure (phospho-lipid fatty acid analysis) in the topsoil were determined.
Gross N mineralization was about ten times lower in the agro-ecosystems than in the forest, while gross nitrification was
low in all sites. Gross N immobilization equalized or exceeded the gross inorganic N production in all sites. Microbial biomass
was 3–5 times more abundant in the forest than in the agro-ecosystems. A positive relationship between the ratio fungi/bacteria
and total microbial biomass was observed in these Andisols. We suggest that the reduction in fungal biomass induced a lower
extracellular enzyme production and limited soil organic matter depolymerisation in the agro-ecosystems. We conclude that
soil N cycling was unable to provide a significant N input for the croplands, but also the risk for ecosystem N losses was
low, even under fallow soil conditions. Current fertilization practices appropriately anticipated the soil N cycling processes,
but further research should indicate the potential of alternative land management to reduce fertilizer cost. 相似文献
79.
Alla Popova Ghita Geoffroy Marie-France Renou-Gonnord Pascal Faucon Ellis Gartner 《Journal of the American Ceramic Society》2000,83(10):2556-2560
To better understand the mechanism of interaction between hydrating silicate-based cements and polymeric dispersants of the type used as "superplasticizers" in modern construction concretes, two different types of polymeric dispersant were added (at concentrations of 1 and 10 g/L) during the synthesis of calcium silicate hydrate (C-S-H) via the "pozzolanic reaction" in dilute slurries of lime and reactive silica, at Ca/Si ratios in the range of 0.66–1.50. Although both polymers gave degrees of adsorption of >79% in all cases studied, no significant structural modifications of the resulting C-S-H products were observed via X-ray diffraction or 29 Si magic angle spinning–nuclear magnetic resonance. These results differ from recent work in which it was shown that similar types of polymer could intercalate into the interlayers of C-S-H that was made using an alternative process. It is suggested that the process by which the C-S-H is formed may have a strong influence on whether C-S-H can intercalate polymers. This observation is relevant to understanding the fate of such polymers in concrete. 相似文献
80.
This paper presents a robust indirect adaptive controller for a class of robots which have a flexible beam as last link. Since the relation between the joint space and the workspace depends on both the kinematics and the dynamics, a virtual joint space is defined so as to be related kinematically to the workspace. In fact, the transformation is defined from the virtual joint space to the joint and deformation spaces. Since the robot is a non‐minimum‐phase system in the virtual joint space, the transformation is obtained, in‐line by the iterative use of the causal–anticausal approach. Based on that transformation, a robust adaptive controller can be designed to ensure robust and fast convergence of the tracking error in the joint, deformation and virtual joint spaces. The controller thus obtained is simulated for a manipulator having one rigid and one flexible link. The simulation results demonstrate the good performances and the robustness of the system. © 2001 John Wiley & Sons, Inc. 相似文献