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81.
C Hauser-Kronberger GW Hacker K Albegger A Saria WH Muss J Schl?hmicher-Thier O Dietze 《Canadian Metallurgical Quarterly》1994,42(2):89-98
Asymmetry in the face and dentition is a naturally occurring phenomenon. In most cases facial asymmetry can only be detected by comparing homologous parts of the face. The etiology of asymmetry includes: a) Genetic or congenital malformations e.g. hemifacial microsomia and unilateral clefts of the lip and palate; b) Environmental factors, e.g. habits and trauma; c) Functional deviations, e.g. mandibular shifts as a result of tooth interferences. Dental asymmetries and a variety of functional deviations can be treated orthodontically. On the other hand, significant structural facial asymmetries are not easily amenable to orthodontic treatment. These problems may require orthopedic correction during the growth period and/or surgical management at a later point. Patient complaints and desires need to be addressed since they may vary from unrealistic expectations to a lack of concern even in the presence of large deviations. With mild dental, skeletal and soft tissue deviations the advisability of treatment should be carefully considered. 相似文献
82.
Thomas Kubin Praveen Gajawada Peter Bramlage Stefan Hein Benedikt Berge Ayse Cetinkaya Heiko Burger Markus Schnburg Wolfgang Schaper Yeong-Hoon Choi Manfred Richter 《International journal of molecular sciences》2022,23(3)
Oncostatin M (OSM), a member of the interleukin-6 family, functions as a major mediator of cardiomyocyte remodeling under pathological conditions. Its involvement in a variety of human cardiac diseases such as aortic stenosis, myocardial infarction, myocarditis, cardiac sarcoidosis, and various cardiomyopathies make the OSM receptor (OSMR) signaling cascades a promising therapeutic target. However, the development of pharmacological treatment strategies is highly challenging for many reasons. In mouse models of heart disease, OSM elicits opposing effects via activation of the type II receptor complex (OSMR/gp130). Short-term activation of OSMR/gp130 protects the heart after acute injury, whereas chronic activation promotes the development of heart failure. Furthermore, OSM has the ability to integrate signals from unrelated receptors that enhance fetal remodeling (dedifferentiation) of adult cardiomyocytes. Because OSM strongly stimulates the production and secretion of extracellular proteins, it is likely to exert systemic effects, which in turn, could influence cardiac remodeling. Compared with the mouse, the complexity of OSM signaling is even greater in humans because this cytokine also activates the type I leukemia inhibitory factor receptor complex (LIFR/gp130). In this article, we provide an overview of OSM-induced cardiomyocyte remodeling and discuss the consequences of OSMR/gp130 and LIFR/gp130 activation under acute and chronic conditions. 相似文献
83.
Claudia Waldinger Manfred Schneider 《Journal of the American Oil Chemists' Society》1996,73(11):1513-1519
Lipases that display high regioselectivities and broad substrate tolerance were used as catalysts for the efficient esterification
of glycerol under the conditions of irreversible acyl transfer. A variety of unsaturated fatty acids, such as oleic, linoleic,
erucic, ricinolic, hydroxystearic and coriolic acid, were used for this purpose in the form of their vinyl esters. Suitable
biocatalysts were chosen on the basis of systematic screening experiments regarding their regioselectivities (RE) and substrate
tolerances. Distinct differences were found and expressed in numerical RE values as a measure for differences of these biocatalysts
as being specific, selective, and nonspecific. Based on these experiments, a variety of molecules were synthesized on a preparative
scale (>150 mmol) in good yield (ca.85%) and with high regioisomerical purities (>95% RE). 相似文献
84.
Manfred Held 《Propellants, Explosives, Pyrotechnics》1991,16(1):21-26
An analysis of the secondary fragments emerging from a target plate has shown that their mass distribution fits excellently to a formula established earlier by the author. This applies equally well to the secondary fragments of an explosive-formed fragment from a multi-P warhead, to those from the warhead's structural casing. and even to the fragments from the target plate itself, as well as to the sum of all of these 3 types of fragements. The correlation coefficient for the two constant parameters governing this formula (namely, the scaling factor B and the form factor λ) is always better than 0.99, when an optimum total mass Mo is southt and inserted, and when the first, large fragements are not included in the consideration, which means when one or two measured points are negiected. For secondary fragements, the form factor λ in the mass distribution is close to 1/2 = 0.5, whereas for the natural fragments of HE projectiles it is in the order of 2/3. namely, from 0.6 to 0.8. 相似文献
85.
86.
Manfred Held 《Propellants, Explosives, Pyrotechnics》1989,14(4):153-161
All high explosives, at least the ones used in military applications, have a specific minimum detonation radius, Rmin with which the detonation can change its direction through 90° or 180°. It is to be emphasized that this applies not only to thc so-called insensitive high explosives, but the sensitive explosives of course have smaller radii than the insensitive ones. The corner-turning distance, As, determined in the radial test, also corresponds to the minimum radius, Rmin for the detonation wave to invert its direction through 180°. The radial test is a simple method, with regard to both design and analysis, that is suitable for determining the 90°-distance, or the minimum detonation radius, Rmin. 相似文献
87.
Florian Röper Markus Wolfahrt Sandra Schlögl Georg Kucher Gerald Pinter 《应用聚合物科学杂志》2019,136(19):47506
Repair of composite structures and the impact of demanding environmental conditions is a crucial issue for the aircraft industry because of the increasing use of composites in modern aircraft. Consequently, the impact of environmental conditions common for aircraft applications on repair specimens in comparison to nonrepaired specimens is studied. All specimens are produced from a woven carbon fiber-reinforced epoxy-based prepreg. For the repair-specimens, an epoxy-based film adhesive is used for the soft patch repair approach. During the repair process, the surface of the precured prepreg is prepared by a mechanical method (sanding) and an additional chemical functionalization, respectively. Moisture absorption of the repair specimens is independent of the surface preparation method and higher for the repaired than for the nonrepaired specimens. The key influencing environmental conditions for the tensile strength and the failure mode of the repair specimens are elevated temperature testing as well as hot/wet conditioning and conditioning in deionized water. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47506. 相似文献
88.
Christoph Spiegel Manfred Kraut Georg Rabsch Christof Küsters Wolfgang Augustin Stephan Scholl 《化学工程与技术》2019,42(10):2067-2075
The application of highly effective microstructured devices in continuous production and industrial environments is frequently prone to fouling. A new method is presented to characterize fouling in these microstructures. Thermal fouling of aqueous solutions containing whey protein were used as a test system. Different fouling effects could be observed and distinguished. Integral fouling indicators, such as thermal fouling resistance and pressure drop, as conventional criteria for the occurrence of fouling were compared with direct local optical observation. Low thermal fouling resistances could be detected. 相似文献
89.
Zaoli Zhang Wilfried SigleChristoph T. Koch Manfred Rühle 《Journal of the European Ceramic Society》2011,31(9):1835-1840
We report about the dynamic behavior of a nanometer-scale amorphous intergranular film (IGF) in a Si3N4 ceramic by an in situ heating experiment in a high-resolution transmission electron microscopy (HRTEM). During the experiment the IGF gradually vanishes at 820 °C accompanied by the formation of crystal planes within the IGF. The IGF reappears after cooling back to room temperature. The results cannot be explained within the framework of a force balance model. We argue that the dynamic behavior of the IGF in our experiment originates from the open system observed. 相似文献
90.