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991.
电影院设计不但要使立面效果美观大方,各种影音设施齐备完善,而且应为观众提供一个舒适、安全的观赏环境。论文以一具体工程为例,分析了影院建筑的特点,具体阐述了放映厅和放映机房空调和通风系统的确定,以及影厅消防排烟设计上的特点与要点。为读者提供了一种电影院空调通风及排烟系统设计的思路,并指出了设计时区别于其他类型建筑设计的关键点。 相似文献
992.
Organic wrinkle structures are investigated as an internal scattering layer for the fabrication of highly efficient organic light-emitting diodes (OLEDs). The solution-processed wrinkle structures are planarized with a high-index layer, resulting in a reduced surface roughness and optical haze simultaneously. The OLED device including the wrinkle structures achieved external quantum efficiency (EQE) of 24.2%, corresponding to a 1.24 time enhancement with respect to that of a control device having no internal scattering layer. By attaching a micro lens array (MLA) or a half ball lens (HBL) on the external surface of the substrate, the proposed device exhibits an EQE of 30.5% (1.56 time enhancement) and 41.8% (2.14 time enhancement), respectively. Randomness of the distributed wrinkle structures is shown to provide additional benefits of reduced angular spectral distortion and Lambertian-like emission properties. Trans-scale optical simulation combining wave-optics and the geometrical effect are used for the quantitative analysis of the emission characteristics of the device. 相似文献
993.
Melia azedarach L. is a plant with wide use in folk medicine since it contains many bioactive compounds of interest. The present study aimed to extract bioactive compounds from M. azedarach fruits by a sequential process in fixed bed using various solvent mixtures. Extractions were performed at 50 °C and 300 bar in four sequential steps using supercritical CO2 (scCO2), scCO2/ethanol, pure ethanol, and ethanol/water mixture as solvents, respectively. The efficacy of the extraction process was evaluated by extraction yield and kinetics, and analysis of extracts by: (1) thin layer chromatography (TLC), (2) phenolics content, (3) reduction of surface tension of water, (4) gas chromatography (GC–MS), (5) electrospray ionization mass spectrometry (ESI–MS) and (6) antiviral activity. The overall extraction yield reached 45% and TLC analysis showed extracts with different composition. extract obtained from CO2/ethanol mixture (SCEE) exhibited the greatest ability to reduce surface tension of water from 72.4 mN m−1 [1] of pure water to 26.9 mN m−1 of an aqueous solution of 40 g L−1. The highest phenolics contents were observed in both the hydroalcoholic extract and scCO2/ethanolic extract. Volatile oils were not detected in the supercritical extracts by GC–MS. MS analyses identified the fatty acids: linoleic, palmitic and myristic acid in the supercritical extract (SCE), and the phenolics: caffeic acid and malic acid in the other extracts. In addition, SCE and SCEE extracts showed significant inhibition percentage against Herpes Simplex Virus Type 1. The extraction process proposed in the present study produced extracts with significant potential for application in food and pharmaceutical industries. 相似文献
994.
Mary Bergstein 《History of Photography》2017,41(3):217-240
Léopold Szondi invented a projective test using photographs of people with mental pathologies to determine the unconscious, ancestral illnesses (or aptitudes) of his subjects. Szondi’s images were garnered from psychiatric textbooks published around 1900. Such photographs presumably revealed unconscious thoughts, desires, and destinies in the course of a test session. If a patient responded positively to a photo-portrait of a diagnosed ‘hysteric’, for instance, this indicated that the subject herself had unconscious, inherited hysterical traits. Szondi’s reasoning was predicated upon two commonly held fallacies: first that an individual’s physical appearance is the external marker of mental life, and second that photography is a transparent means of revealing true facts. In spite of (or maybe even because of) such problematic assumptions, Szondi’s use of photographs can be located historically in a tradition of reading human character from portraiture. The test was widespread, and was even administered to Adolf Eichmann at the time of his trial in Jerusalem – an ironic cultural development as Szondi himself would have been among the thousands of Jews deported from Hungary directly to Auschwitz by Eichmann had the Szondi family not been rescued by the Kastner train of 1944. 相似文献
995.
996.
This paper exhibits new recursive implementation of the root-MUSIC algorithm in power system applications in order to extract the instantaneous power disturbances, which emanate from the arc furnace. The MUSIC algorithm is selected because it has an outstanding capability to estimate and track the frequencies of all types of distortion such as harmonics and interharmonics. The utilized algorithm has been newly developed so as to recursively track the instantaneous disturbances in the arc furnace current and consequently mitigate them. The suggested development of the recursive root-MUSIC is compared with the ESPRIT in order to prove that the adopted technique outperforms the high-resolution common techniques in a noisy or non-noisy environment. The instantaneous disturbance is formed by an innovative formulation of the recursive notch filter. Moreover, the experimental results are given to prove the practicality of the proposed concepts and techniques. 相似文献
997.
Cardoon (Cynara cardunculus L.) is an important perennial energy plant, which may produce sufficient biomass under reduced inputs. A 4-years field study was conducted in northern Greece and was repeated for three years in central Greece to determine the productivity of two cardoon varieties (‘Bianco Avorio’ and ‘C12’) under different water (irrigated or non-irrigated) and weed control (weedy or weed-free) conditions. In northern Greece, the density of weeds grown with cardoon increased as years went by, but in central Greece decreased. The absence of irrigation and the presence of weeds significantly reduced cardoon dry biomass, seed and oil yields, especially in the first two years of cultivation. In both environments, irrigated with 90 mm cardoon achieved 22–42% and 35–42% greater dry biomass and seed yield, respectively, than achieved the non-irrigated crop. In weedy cardoon, the dry biomass or seed yields reductions were 33–66% or 41–64%, respectively, in central Greece and 21–95% or 8–99%, respectively, in northern Greece. In central Greece cardoon productivity increased as years went by, but in northern Greece decreased. Generally, the cv. C12 was more productive than the cv. Bianco Avorio. Conclusively, the cardoon cv. C12 could provide satisfactory dry biomass, seed and oil yields for energy use in semi-arid Mediterranean fields, without irrigation or weed control inputs, on condition that they have been successfully established the first year. However, cardoon should be irrigated and weeded in order to provide sufficient yields. 相似文献
998.
Sustainable production of second-generation energy crops on marginal land holds a great potential for renewable energy development. Because a vast area of marginal land is located in the arid and semiarid regions of the world, water shortage is the most serious environmental limitation. In this study, we developed a water balance model to address the question of whether Miscanthus energy crops can be sustainably produced in the Loess Plateau of China, a region of more than 60 million hectares particularly abundant in semiarid marginal land. The simulation of 20-year soil water content in bare soil, the winter wheat field, and the Miscanthus field across the Loess Plateau suggested that the long-term production of Miscanthus would not cause water depletion in deep soil. This finding addressed a serious concern that growing high-biomass plants in the Loess Plateau might lead to deep-soil water depletion, which was suggested to be the cause of previous failure of afforestation. Planting Miscanthus was effective in reducing surface runoff and consequently preventing water and soil loss in this heavily eroded region. The model and analyses illustrated where in the Loess Plateau this perennial energy crop could be produced with stable and sufficient yield. 相似文献
999.
《Measurement》2014
Soil moisture content has paramount importance in dictating engineering, agronomic, geological, ecological, biological and hydrological characteristics of the soil mass. Though earlier researchers have employed various techniques of moisture content determination of soils, both in laboratory and in situ conditions, ascertaining the applicability of these techniques to soils of entirely different characteristics and the ‘types of moisture content’, which they can measure, is still a point of debate. As such, a critical review of all the established and emerging soil moisture measurement techniques with respect to their merits and demerits becomes necessary. With this in view, efforts have been made in this paper to critically evaluate all the soil moisture measurement techniques, limitations associated with them and the influence of various soil-specific parameters (viz., mineralogy, salinity, porosity, ambient temperature, presence of the organic matter and matrix structure of the soil) on the measured soil moisture content. This paper also highlights the importance of various innovations based on Micro Electro Mechanical Systems (MEMS) and nano-sensors that are emerging in this context. 相似文献
1000.
《Journal of Visual Communication and Image Representation》2014,25(5):1262-1274
Historical cadastral maps are valuable sources for historians to study social and economic background of changes in land uses or ownerships. In order to conduct large-scale historical research, it is essential to digitize the cadastral maps. As being established in antiquity, however, they suffer from significant noise artifacts attributed to hand-drawn cartography. In this paper, we propose a novel method of extracting land regions automatically in historical cadastral maps. First, we remove grid reference lines based on the density of the black pixel with the help of the jittering. Then, we remove land owner labels by considering morphological and geometrical characteristics of thinned image. We subsequently reconstruct land boundaries. Finally, the land regions of a user’s interest are modeled by their polygonal approximations. Our segmentation results were compared with manually segmented results and showed that the proposed method extracted the land regions accurately for assisting cadastral mapping in historical research. 相似文献