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51.
In this study, flow cytometry was used for assessing and comparing the genome size (GS) and the whole genome base composition (AT/GC ratio) of the saw-toothed grain beetle Oryzaephilus surinamensis (L.). In addition, the presence and frequency of endosymbiotic Wolbachia bacteria was studied. The haploid GS was estimated to lie within the range of 151.5-154 Mbp in O. surinamensis, making it the smallest value of haploid GS known among beetles. Furthermore, it was found that in eight silo pest populations GS was significantly smaller than in eight feral (native) populations obtained from fallen oak acorns. The ability of O. surinamensis to colonize different habitats globally could be connected with an unusually AT-rich (for an invertebrate) genome (AT-base content ranging from 68 to 76%). Native (feral) populations of O. surinamensis appear to have genetically diverged from the storage-pest populations tested. Larvae of pest origin survived better than larvae of native (feral) origin under laboratory conditions, which resembled silo conditions more than natural habitats. 相似文献
52.
Sukhdeep Kaur Sukhleen Bindra Narang Deep Kamal Kaur Randhawa 《Journal of Electronic Materials》2018,47(11):6467-6475
In this paper, the thermoelectric performance of porous armchair graphene nanoribbons under tensile and compressive strain is investigated as a function of pore morphology and temperature. For all the porous structures irrespective of their pore size, the performance improves at a compressive strain of 10%, while for tensile nature, the minimum cut-off strain required for improved thermoelectric figure of merit (ZT) shows an inverse relation with the pore size. In addition, optimal pore shape geometry can yield better performance, even at lower values of strain. Further analysis reveals that tensile strain is not able to improve the performance at low and intermediate temperatures of around 300 K, whereas tensile/compressive strain is effective in enhancing the performance of porous armchair graphene nanoribbons at higher temperatures. Furthermore, the structures are found to be more sensitive to compressive strain than the tensile one since the effect of compressive strain is found to improve ZT more significantly. Our analysis based on Non-Equilibrium Green’s function calculations suggests a possible route for tailoring the functionality of nanomaterials so as to achieve great potentials for thermoelectric applications at various temperatures. 相似文献
53.
Fine-grain MPI (FG-MPI) extends the execution model of MPI to allow for interleaved execution of multiple concurrent MPI processes inside an OS-process. It provides a runtime that is integrated into the MPICH2 middleware and uses light-weight coroutines to implement an MPI-aware scheduler. In this paper we describe the FG-MPI runtime system and discuss the main design issues in its implementation. FG-MPI enables expression of function-level parallelism, which along with a runtime scheduler, can be used to simplify MPI programming and achieve performance without adding complexity to the program. As an example, we use FG-MPI to re-structure a typical use of non-blocking communication and show that the integrated scheduler relieves the programmer from scheduling computation and communication inside the application and brings the performance part outside of the program specification into the runtime. 相似文献
54.
Inspired by an intuitive analogy that exists between the gray level textures and the miscibility in the multiphase fluids,
the aura concept was developed from set theory tools in order to modeling the texture image. The gray level aura matrix (GLAM)
has been then proposed to generalize the gray level cooccurrence matrix (GLCM) which remains very popular in the texture analysis.
The GLAM indicates how much each gray level is present in the neighborhood of each other gray level. The neighborhood is defined
by a structuring element as one used in mathematical morphology. The GLAM is mainly used and studied in synthesis and classification
of textures framework but very few works are devoted to the segmentation. The aim of this paper is to exploit the GLAM for
the segmentation of textured images. Experiments results over synthetic and real images show the efficiency of the GLAM. The
influence of the shape and the size of the structuring element on the segmentation results are also studied. 相似文献
55.
56.
Effect of Operational Parameters on Determination of Oxidative Stability Measured by Rancimat Method
Nilkanth Pawar Akash Purohit Kamal Gandhi R.R.B. Singh 《International Journal of Food Properties》2013,16(9):2082-2088
Operational parameters of Rancimat, including sample weight (3, 6, 9 g), airflow rate (10, 15, 20 L/h) and temperature (110, 120, 130°C) were evaluated to determine their effects on oxidative stability index, temperature coefficient, Q10 number, and shelf life prediction of ghee (anhydrous milk fat). These parameters showed statistically significant effects on the oxidative stability index. It was observed that when the sample weight and airflow rate at a given temperature were at saturated air condition, the oxidative stability indexes showed no significant differences (p < 0). As the temperature increased, oxidative stability index decreased and average coefficient of variation was minimal at 120°C. The conditions under which the ghee sample was saturated with air and had a relatively lower oxidative stability index, was with sample weight of 6 g, temperature at 120°C and an airflow rate of 15 L/h. Temperature coefficient and Q10 number were independent of sample weight and air flow rate, however, they had a significant effect on shelf life prediction of ghee. 相似文献
57.
Kamal J. K. Gandhi Daniel W. Gilmore Robert A. Haack Steven A. Katovich Steven J. Krauth William J. Mattson John C. Zasada Steven J. Seybold 《Journal of chemical ecology》2009,35(12):1384-1410
From 2000 through 2003 we used semiochemical-baited traps in northeastern Minnesota, USA, to assess changes in assemblages
of subcortical forest insects after a catastrophic wind storm in 1999 and subsequent (1999–2000) fuel-reduction activities
(salvage-logging and prescribed-burning). We determined the regional efficacy of fifteen semiochemical blends (pheromones
and kairomones) as attractants for target and non-target subcortical insect species (Coleoptera: Anthribidae, Buprestidae,
Cerambycidae, Cleridae, Cucujidae, Curculionidae, Histeridae, Nemonychidae, Salpingidae, Scolytidae, Tenebrionidae, and Hymenoptera:
Siricidae). During the four summers, we trapped 86,471 subcortical insects (143 species) in baited and unbaited Lindgren funnel
traps, and 500 beetles (44 species) in baited and unbaited pitfall traps. We report 23 new state collection records of subcortical
insects from Minnesota. Trap catches of subcortical insects were greatest in the wind-disturbed areas 2 years after the event,
and declined thereafter. Similar trends were observed for subcortical insects in the burned areas. Both wind-disturbance and
burning increased the subcortical insect species richness and diversity on the landscape. The subcortical insect species compositions
of the salvaged and burned forest areas differed from those of the undisturbed and wind-disturbed areas. Trap catches of subcortical
insects in response to semiochemical treatments also varied with year of sampling and land-area treatment. The greatest diversity
of subcortical beetle species was in traps baited with attractants for the scolytids, Dendroctonus valens [(+)-α-pinene and (−)-β-pinene] and Dryocoetes spp. [exo-brevicomin and (−)-α-pinene], perhaps reflecting the generic nature of the baits. The most distinct species compositions
were collected in response to the woodborer and Dendroctonus simplex baits, whereas the species compositions in traps with the D. valens and Dryocoetes spp. baits, and the unbaited funnel trap were the most similar. The variation in trap catch with time and across landscapes
suggests that the responses of subcortical insects to semiochemicals are more complex than previously appreciated. 相似文献
58.
This study was conducted in the Tafresh area of Iran to assess the dietary patterns, time allocation, and nutritional status of rural women in relation to their participation in mixed farming activities. We selected 75 women from 40 villages by applying a stratified random-sampling technique. Cereals and grains were the major source of energy intake. According to the recommended dietary allowance (RDA) tables of India, the United States, the United Kingdom, and the Food and Agriculture Organization (FAO), the respondents seemed to have no micronutrient and energy deficiencies during the spring season. They spent most of their time and energy on household, animal husbandry, and crop farming activities. According to measurements of body mass index (BMI), the respondents were well nourished. However, despite the high level of BMI, analysis suggested a negative energy balance. Nevertheless, analysis indicated that rural women with negative energy balance spent more time and energy in mixed farming and had a higher level of participation in related activities. Hence, it is evident from the results that the physical contribution of rural women in mixed farming activities has a detrimental effect on their nutritional status, at least during some parts of the year (e.g., spring or summer). Therefore, there is a need to adjust nutritional interventions to improve the sustainability of their food intake and to develop appropriate technologies in mixed farming to alleviate their work burdens. 相似文献
59.
Helen Shipton Doris Fay Michael West Malcolm Patterson Kamal Birdi 《Creativity & Innovation Management》2005,14(2):118-128
There is growing evidence available to suggest that Human Resource Management (HRM) practice is an important predictor of organizational performance. Drawing upon organizational learning perspectives, we argue that HRM systems also have the potential to promote organizational innovation. We present longitudinal data from thirty‐five UK manufacturing organizations to suggest that effective HRM systems – incorporating sophisticated approaches to recruitment and selection, induction, appraisal and training – predict organizational innovation in products and production technology. We further show that organizational innovation is enhanced where there is a supportive learning climate, and inhibited (for innovation in production processes) where there is a link between appraisal and remuneration. 相似文献
60.
AA al-Jafari MA Kamal NH Greig AS Alhomida ER Perry 《Canadian Metallurgical Quarterly》1998,248(1):180-185
The elastic properties of carotid arteries of spontaneously hypertensive rats (SHR) and normotensive controls (Wistar-Kyoto rats [WKY]) were examined in vivo, in situ, and in vitro. The changes of internal diameter were measured with a high-resolution A-mode echo-tracking device simultaneously with the intra-arterial pressure at the carotid. The internal diameter at mean arterial blood pressure (MBP) was substantially smaller in vitro than in vivo in SHR (-33.8%) and WKY (-48.3%). The arterial distensibility was lower in vitro in all arteries compared with in vivo conditions (SHR, -30.1%; WKY, -60.4%; at MBP) despite a reduced incremental elastic modulus in vitro (SHR, -56.9%; WKY, -45.1%; at MBP). However, the in vitro and in vivo measurements show consistent elastic behavior of the carotid arteries between both strains of rats. Carotid arteries from WKY were also examined in situ. Although no significant reduction in internal diameter could be observed in situ, distensibility was dramatically decreased (-87% at MBP). These results emphasize the importance of considering the original vascular geometry when determining elastic properties of arteries. We conclude that experimental conditions are likely to be a critical determinant for the assessment of the mechanical properties of conduit vessels. 相似文献