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101.
Olfa Bachrouch Jouda Mediouni-Ben Jema Aidi Waness Wissem Thierry Talou Brahim Marzouk Manef Abderraba 《Journal of Stored Products Research》2010,46(4):242-247
This study reports investigations on the chemical constituents and fumigant toxicity of Pistacia lentiscus L. (Anacardiaceae) essential oil against two major stored-date insects, carob moth Ectomyelois ceratoniae Zeller and Mediterranean flour moth Ephestia kuehniella Zeller. Results showed that P. lentiscus essential oil contained terpinene-4-ol (23.32%), α-terpineol (7.12%) and β-caryophyllene (22.62%) as major compounds. Fumigant toxicity tests showed that P. lentiscus oil was more toxic to E. kuehniella (LC50 = 1.84 μl/l, LC95 = 5.14 μl/l) than E. ceratoniae (LC50 = 3.29 μl/l, LC95 = 14.24 μl/l). The fecundity and hatching rate of both insects decreased with increases in concentration or exposure time to the oil. At 136 μl/l air, fecundities and hatching rates were respectively 35 eggs/female and 42.86% for E. ceratoniae and 78 eggs/female and 29.49% for E. kuehniella. 相似文献
102.
Christophe Nguyen Fabienne Froux Sylvie Recous Thierry Morvan Christophe Robin 《Nutrient Cycling in Agroecosystems》2008,80(1):39-47
Repeated fertilisation of crops with manure commonly increases both the amount and the quality of soil organic matter, the
mineralisation of which strongly determines the availability of N to plants. In the rhizosphere, the microbial mineralisation/immobilisation
of N is enhanced due to rhizodeposition (release of organic compounds from roots). In this work, we studied N transformations
during incubation of maize root mucilage in soils that had been previously fertilized with composted pig manure or with ammonium
nitrate for 7 years. Our work revealed mucilage was rapidly mineralised (average half-life of 3 days), inducing a rapid N
immobilisation of 94 mg N g−1 of mucilage C, followed by a slow remineralisation. Fertilisation with manure induced a persistent stimulation of the soil
organic matter mineralisation, leading to an enhanced content of soil inorganic N (+23% in 58 days of incubation). Due to
this stimulation of microbial activity in the soil fertilized with manure, the decrease in inorganic N during the biodegradation
of mucilage lasted a shorter time as compared to the mineral fertilisation. However, the type of fertilisation did not significantly
change the amount of N immobilised. 相似文献
103.
Bernard Charra Guillaume Jean Jean-Marc Hurot Jean-Claude Terrat Thierry Vanel Cyril VoVan Foued Maazoun Charles Chazot 《Hemodialysis international. International Symposium on Home Hemodialysis》2001,5(1):42-50
While nephrologists wait for the ideal, non invasive, inexpensive, precise, and reproducible tool to evaluate extracellular volume (ECV), they need to exert their clinical acumen in the quest of that holy grail, dry weight (DW). Estimation of DW using a clinical approach based on blood pressure (BP) and ECV is feasible and reliable as shown by successful experiences in various dialysis modes over more than three decades. But a need still exists to resolve difficulties associated with accurate assessment of BP (methods and circumstances of measurement, and the confounding effects of antihypertensive drugs) and ECV (evaluation of weight changes unrelated to ECV, lack of specificity and sensitivity of clinical symptoms, lag time, confusion in terminology). An essential point in clinical assessment of DW is that a normal BP is at the same time the target and the crucial index of DW achievement. For this reason, a trialand‐error “probe” process has to be used at intervals to make sure that the dry weight target point is correctly estimated. The various “non clinical” methods proposed for dry weight assessment increase the complexity and the cost of hemodialysis. They are, in the present state of things, more clinical research than practice tools. They do not replace clinical judgment. 相似文献
104.
Jean-José Jacq Thierry Cresson Valérie Burdin Christian Roux 《IEEE transactions on bio-medical engineering》2008,55(5):1620-1633
This paper addresses the problem of the robust registration of multiple observations of the same object. Such a problem typically arises whenever it becomes necessary to recover the trajectory of an evolving object observed through standard 3-D medical imaging techniques. The instances of the tracked object are assumed to be variously truncated, locally subject to morphological evolutions throughout the sequence, and imprinted with significant segmentation errors as well as significant noise perturbations. The algorithm operates through the robust and simultaneous registration of all surface instances of a given object through median consensus. This operation consists of two interwoven processes set up to work in close collaboration. The first one progressively generates a median and implicit shape computed with respect to current estimations of the registration transformations, while the other refines these transformations with respect to the current estimation of their median shape. When compared with standard robust techniques, tests reveal significant improvements, both in robustness and precision. The algorithm is based on widely-used techniques, and proves highly effective while offering great flexibility of utilization. 相似文献
105.
Mechanical Properties of Dry-Pressed Ceramic Green Products: The Effect of the Binder 总被引:3,自引:0,他引:3
Samir Baklouti Thierry Chartier Jean François Baumard 《Journal of the American Ceramic Society》1997,80(8):1992-1996
The strength of alumina green samples prepared by uniaxial pressing of powders spray-dried with two binders such as poly(ethylene glycol) or poly(vinyl alcohol) is discussed in terms of (i) the adhesive properties of the polymer-rich external layer of spray-dried granules and (ii) the mechanical properties of this layer. A transition from intra- to intergranular fracture is observed when the glass transition temperature of the binder increases. The influence of the binder on the defect size distribution in the green products is investigated using the classical Weibull statistics. 相似文献
106.
Thierry Madiès 《The Annals of Regional Science》2008,42(1):225-233
When both vertical and horizontal externalities are at work in a federation, they generally distort levels of taxation in
opposite directions. This article is an extension of the Keen and Kotsogiannis (Am Econ Rev March: 363–370, 2002) model. It
focuses on state tax policy when states provide an industrial public good increasing firms’ marginal productivity rather than
a residential public good intended to households. We find that some results related to whether equilibrium state taxes are
likely to be too high or too low are much more complex when state-provided industrial public goods are considered. First,
we show that in the presence of industrial public goods, a dominant vertical externality may result in state tax rates being
too low (and not too high as it is the case with residential public goods). Second, we find that under certain conditions,
horizontal and vertical externalities may point in the same direction and reinforce each other towards tax rates being too
high or too low. 相似文献
107.
This work deals with relaxed conditions for stability and stabilization of discrete-time Takagi–Sugeno (TS) models. It recalls classical results found in the literature which use quadratic Lyapunov functions leading to very conservative conditions, and various extensions based on piecewise and non-quadratic Lyapunov functions. Afterwards, a new and powerful way to enhance the previous results is depicted. The basic idea is that waiting long enough a stable model will converge towards its equilibrium and, therefore, the Lyapunov functions under consideration are not necessarily decreasing at every sample, but are allowed to decrease every k samples. Whatever it is k >1, the results are proved to include the standard one-sample case. The potential of this approach is shown through several examples in the paper. 相似文献
108.
Alberto Mazzoldi Mario Tesconi Alessandro Tognetti Walter Rocchia Giovanni Vozzi Giovanni Pioggia Arti Ahluwalia Danilo De Rossi 《Materials science & engineering. C, Materials for biological applications》2008,28(7):1057-1064
Carbon nanotube (NT) actuators were fabricated using the micromolding method. In order to prevent the nanotubes from aggregating, they were enclosed in a partially cross-linked polyvinylalcohol–polyallylamine matrix. A unimorph matrix bender in the form of a small multi-layered strip, 5 mm × 15 mm was fabricated. The resulting composite system: NT/PVA, solid polymer electrolyte and metal contact, was characterised using impedance analysis and cyclic voltammetry. Initial measurements on electro-mechanical transduction show a conversion efficiency of 0.2 μm/mV. An electrochemical model of the impedance of the system was then developed, with which the experimental results agree fairly well. 相似文献
109.
Sebastian Hermeth Gabriel Staffelbach Laurent Y.M. Gicquel Vyacheslav Anisimov Cinzia Cirigliano Thierry Poinsot 《Combustion and Flame》2014
Large Eddy Simulations (LES) are used to study a lean swirl-stabilized gas turbine burner where the flow exhibits two stable states. In the first one, the flame is attached to the central bluff body upstream of the central recirculation zone which contains burnt gases. In the second one the flame is detached from the central bluff body downecirculation zone which is filled by cold unburnt gases and dominated by a strong Precessing Vortex Core (PVC). The existence of these two states has an important effect on the dynamic response of the flame (FTF): both gain and phase of the FTF change significantly in the detached case compared to the attached one, suggesting that the stability of the machine to thermoacoustic oscillations will differ, depending on the flame state. Bifurcation diagrams show that the detached flame cannot be brought back to an attached position with an increased fuel flow rate, but it can be re-attached by forcing it at high amplitudes. The attached flame however, behaves inversely: it can be brought back to the detached position by both decreasing or increasing the pilot mass flow rate, but it remains attached at all forcing amplitudes. 相似文献
110.
Bart Van Looy Thierry Martens Koenraad Debackere 《Creativity & Innovation Management》2005,14(3):208-221
Organizing for innovation does not present itself as a straightforward exercise. The complexities entailed when implementing an innovation strategy can be related directly to the multitude of objectives it comprises. Recently, several scholars have advanced the notions of semi‐ or quasi‐structures and ambidextrous organizations to handle these multiple requirements. These organizational forms imply the simultaneous presence of different activities, exhibiting differences in technology and market maturation. As a consequence, financial returns will reflect this diversified resource allocation pattern. Moreover, as higher levels of complexity are being introduced; ambidextrous organizations will encounter additional, organizational, costs. Compared to organizations that focus on the most profitable part of the portfolio, ambidextrous organizations – ceteris paribus – tend to be inferior in terms of financial returns. Within this contribution we explore under which conditions ambidextrous organizations can outperform focused firms; considered a prerequisite for their sustainability. In order to do so, we develop an analytical framework depicting the differential value dynamics, focused and ambidextrous firms can enact. Our findings reveal the relevancy of adopting extended time frames as well as introducing interface management practices aimed at cross‐fertilization. Finally, the synergetic potential of (underlying) technologies comes to the forefront as necessary in order for ambidextrous organizations to become sustainable. 相似文献