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991.
Umberto Tarantino Ida Cariati Chiara Greggi Elena Gasbarra Alberto Belluati Luigi Ciolli Giulio Maccauro Alberto Momoli Simone Ripanti Francesco Falez Maria Luisa Brandi 《International journal of molecular sciences》2021,22(12)
Cigarette smoking has a negative impact on the skeletal system, as it reduces bone mass and increases fracture risk through its direct or indirect effects on bone remodeling. Recent evidence demonstrates that smoking causes an imbalance in bone turnover, making bone vulnerable to osteoporosis and fragility fractures. Moreover, cigarette smoking is known to have deleterious effects on fracture healing, as a positive correlation between the daily number of cigarettes smoked and years of exposure has been shown, even though the underlying mechanisms are not fully understood. It is also well known that smoking causes several medical/surgical complications responsible for longer hospital stays and a consequent increase in the consumption of resources. Smoking cessation is, therefore, highly advisable to prevent the onset of bone metabolic disease. However, even with cessation, some of the consequences appear to continue for decades afterwards. Based on this evidence, the aim of our review was to evaluate the impact of smoking on the skeletal system, especially on bone fractures, and to identify the pathophysiological mechanisms responsible for the impairment of fracture healing. Since smoking is a major public health concern, understanding the association between cigarette smoking and the occurrence of bone disease is necessary in order to identify potential new targets for intervention. 相似文献
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993.
Antonietta Baiano Tommaso Gomes & Francesco Caponio 《International Journal of Food Science & Technology》2005,40(8):829-834
The hydrolytic and oxidative degradation of olive oil and extra‐virgin olive oil, used as covering liquids in canned dried tomatoes, was studied during storage by means of conventional (acidity, peroxide value, p‐anisidine value) and non conventional (polar compounds) analyses. The effects of the addition of spices were also considered. The hydrolysis and oxidation of olive oil increased faster and was higher than that of extra‐virgin olive oil in terms of absolute values but some other indices, such as percentage of oligopolymers and percentage of oxidized triglycerides, increased faster in extra‐virgin olive oil than in olive oil. The antioxidant effect given by a higher concentration of polyphenols in the extra‐virgin olive oil was shown by a reduced amount of secondary oxidation. However, olive oil and extra‐virgin olive oils showed similar behaviour in terms of peroxide formation. 相似文献
994.
Sergio Casciaro Francesco Conversano Stefano Musio Ernesto Casciaro Christian Demitri Alessandro Sannino 《Journal of materials science. Materials in medicine》2009,20(4):983-989
Tissue mimicking phantoms have been widely reported to be an important tool for development, optimisation and performance
testing of ultrasound-based diagnostic techniques. In particular, modern applications of tissue mimicking phantoms often include
characterisation of the nonlinear behaviour of experimental ultrasound contrast agents. In such cases, the tissue-mimicking
materials should be chosen not only based on the values of their density, speed of sound and attenuation coefficient, but
also considering their effect on the appearance of “native harmonics” due to nonlinear distortion of ultrasound signal during
propagation. In a previous paper it was demonstrated that a cellulose-based hydrogel is suitable to simulate nonlinear acoustical
behaviour of liver tissue for thicknesses up to 8 cm. In this paper we present the experimental characterisation of the nonlinear
acoustical behaviour of a different polyethylene glycol diacrylate (PEGDA)-based hydrogel, in order to assess whether and
how it can improve the performances and overcome some limitations of the cellulose-based hydrogel as liver tissue-mimicking
material. Samples of pig liver tissue, cellulose-based hydrogel and PEGDA-based hydrogel were insonified in a through-transmission
set-up, employing 2.25-MHz pulses with different mechanical index (MI) values. Second harmonic and first harmonic amplitudes
were extracted from the spectra of received signals and their difference was then used to compare sample behaviours. Obtained
results show how a new more accurate and combined experimental model of linear and nonlinear acoustical behaviour of liver
tissue is feasible. In fact, a further confirmation of the cellulose-based hydrogel effectiveness to precisely simulate the
liver tissue for penetration depths up to 8 cm was provided, and it was also shown that the employment of the PEGDA-based
hydrogel can extend the range of useful tissue-mimicking material thicknesses up to 11 cm, moreover allowing a considerable
improvement of the time stability and behaviour reliability of the corresponding manufactured phantoms. 相似文献
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999.
Irene M. Caminiti Francesco Noci Desmond J. Morgan Denis A. Cronin James G. Lyng 《Food and Bioproducts Processing》2012,90(3):442-448
A blend of orange and carrot juice was processed by three selected treatments combining pulsed electric fields (PEF) (24 kV/cm, 18 Hz, 93 μs), ultraviolet light (UV) (10.6 J/cm2) or high intensity light pulses (HILP) (3.3 J/cm2), in each case, with manothermosonication (MTS) technology (400 kPa, 35 °C, 1000 W, 20 kHz). Treatment effects on selected physico-chemical and sensory properties of the juice were evaluated. No significant changes were found in non-enzymatic browning (NEBI) or antioxidant activity compared to an untreated control. However, the treatments increased all the Hunter Lab colour values, while total phenolics were significantly decreased. Each combination achieved on average 78% inactivation of pectin methyl esterase (PME). Sensory analysis showed that the colour of the product processed by hurdle combinations was preferred to that of a pasteurised sample (72 °C, 26 s), while the flavour was adversely affected by all of the non-thermal treatments. Panellists did not perceive differences in the odour, sweetness or acidity of the product. Results indicate that, under the current experimental conditions, the application of the selected combinations of non-thermal technologies resulted in a product in which certain quality attributes were somewhat inferior to those of a lightly pasteurised control juice. 相似文献
1000.
There is now extensive interest in reasoning about moving objects. A probabilistic spatio-temporal (PST) knowledge base (KB) contains atomic statements of the form “Object o is/was/will be in region r at time t with probability in the interval [?,u]”. In this paper, we study mechanisms for belief revision in PST KBs. We propose multiple methods for revising PST KBs. These methods involve finding maximally consistent subsets and maximal cardinality consistent subsets. In addition, there may be applications where the user has doubts about the accuracy of the spatial information, or the temporal aspects, or about the ability to recognize objects in such statements. We study belief revision mechanisms that allow changes to the KB in each of these three components. Finally, there may be doubts about the assignment of probabilities in the KB. Allowing changes to the probability of statements in the KB yields another belief revision mechanism. Each of these belief revision methods may be epistemically desirable for some applications, but not for others. We show that some of these approaches cannot satisfy AGM-style axioms for belief revision under certain conditions. We also perform a detailed complexity analysis of each of these approaches. Simply put, all belief revision methods proposed that satisfy AGM-style axioms turn out to be intractable with the exception of the method that revises beliefs by changing the probabilities (minimally) in the KB. We also propose two hybrids of these basic approaches to revision and analyze the complexity of these hybrid methods. 相似文献