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41.
Mesh of trees (MOT) is well known for its small diameter, high bisection width, simple decomposability and area universality.
On the other hand, OTIS (Optical Transpose Interconnection System) provides an efficient optoelectronic model for massively
parallel processing system. In this paper, we present OTIS-MOT as a competent candidate for a two-tier architecture that can
take the advantages of both the OTIS and the MOT. We show that an n4-n^{4}_{-} processor OTIS-MOT has diameter 8log n
∗+1 (The base of the logarithm is assumed to be 2 throughout this paper.) and fault diameter 8log n+2 under single node failure. We establish other topological properties such as bisection width, multiple paths and the modularity.
We show that many communication as well as application algorithms can run on this network in comparable time or even faster
than other similar tree-based two-tier architectures. The communication algorithms including row/column-group broadcast and
one-to-all broadcast are shown to require O(log n) time, multicast in O(n
2log n) time and the bit-reverse permutation in O(n) time. Many parallel algorithms for various problems such as finding polynomial zeros, sales forecasting, matrix-vector multiplication
and the DFT computation are proposed to map in O(log n) time. Sorting and prefix computation are also shown to run in O(log n) time. 相似文献
42.
Eva Tvrd Daniel Lovíek Elika Glov Marianna Schwarzov Eva Kov
ikov Simona Kunov Jana
iarovsk Miroslava Ka
niov 《International journal of molecular sciences》2022,23(15)
This study focused on the identification of bacterial profiles of semen in normozoospermic men and their possible involvement in changes to the sperm structural integrity and functional activity. Furthermore, we studied possible fluctuations of selected cytokines, oxidative markers, and antibacterial proteins as a result of bacterial presence in the ejaculate. Sperm motility was assessed with computer-assisted sperm analysis, while sperm apoptosis, necrosis and acrosome integrity were examined with fluorescent methods. Reactive oxygen species (ROS) generation was quantified via luminometry, sperm DNA fragmentation was evaluated using the TUNEL protocol and chromatin-dispersion test, while the JC-1 assay was applied to evaluate the mitochondrial membrane potential. Cytokine levels were quantified with the biochip assay, whilst selected antibacterial proteins were quantified using the ELISA method. The predominant species identified by the matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry were Staphylococcus hominis, Staphylococcus capitis and Micrococcus luteus. The results revealed that the sperm quality decreased proportionally to the increasing bacterial load and occurrence of conditionally pathogenic bacteria, including Enterococcus faecalis, Staphylococcus aureus and Escherichia coli. Antimicrobial susceptibility tests revealed a substantial resistance of randomly selected bacterial strains to ampicillin, vancomycin, tobramycin, and tetracycline. Furthermore, an increased bacterial quantity in semen was accompanied by elevated levels of pro-inflammatory cytokines, including interleukin-1, interleukin-2, interleukin-6, tumor necrosis factor alpha as well as ROS overproduction and lipid peroxidation of the sperm membranes. Our results suggest that semen quality may be notably affected by the bacterial quantity as well as quality. It seems that bacteriospermia may be associated with inflammatory processes, oxidative stress, sperm structural deterioration, and a subsequent risk for the development of subfertility, even in normozoospermic males. 相似文献
43.
Schwab KJ Gibson KE Williams DL Kulbicki KM Lo CP Mihalic JN Breysse PN Curriero FC Geyh AS 《Environmental science & technology》2007,41(7):2401-2406
The city of New Orleans, LA was severely impacted by flooding and wind damage following landfall of Hurricane Katrina in August 2005. The city's drinking water infrastructure was severely compromised and massive amounts of sediment were redeposited throughout the flooded region. Thousands of homes were water-damaged resulting in the rapid growth of mold. In September and October 2005 a convenience sample of selected homes, tap water, surface water, and sediment within New Orleans was assessed for mold contamination, microbial contamination, and heavy metal concentrations. At selected sites, indoor mold spore concentrations were compared to outdoor concentrations. The purpose of this study was to conduct a baseline environmental assessment in an effort to identify public health threats caused by wind and flood damage. Surface waters contained high concentrations of bacterial indicators whereas no bacteria were detected in tap water, even from taps containing no chlorine residual. Sediment samples contained concentrations of lead and arsenic similarto pre-Katrina concentrations. Outdoor total spore (sp) concentrations ranged from >6500 to 84 713 sp/m(3). Indoor concentrations ranged from 6142 to 735 123 sp/m(3). For the 13 locations with matched indoor/ outdoor samples, the mean indoor/outdoor spore ratio was 4.11 (ranging from 0.27 to >11.44). Inside 5 of the 13 homes, total spore counts/m(3) exceeded 100 000, with measurements in the moldiest home exceeding 700 000 sp/ m(3). In conclusion, surface waters had high concentrations of bacterial contamination but no bacterial indicators were present in tap water. Sediment samples did not have appreciable increases in lead or arsenic. Flooded homes, however, contained substantial concentrations of mold which could present a public health exposure route to individuals repopulating and restoring the City of New Orleans. 相似文献
44.
Janaína Teles de Faria Eduardo Basílio de Oliveira Valéria Paula Rodrigues Minim Luis Antonio Minim 《International Journal of Food Properties》2017,20(7):1643-1654
The effects of number of homogenization passes, pH, and NaCl concentration on the formation and stability of oil-in-water emulsions comprising a mixture of a biosurfactant (Quillaja bark saponin) and a globular protein (β-lactoglobulin) were investigated. The emulsions were characterized as to visual appearance, droplet size, droplet surface charge, and rheology. The emulsions obtained by different conditions (4, 6, or 8 passes; pH 7, 8, or 9; and 0, 100, or 200 mmol L?1 of NaCl) were polydisperse, presented relatively small average droplet sizes (z-average < 323 nm) as well as negative droplet charge (between –20 and –79.6 mV) in all evaluated conditions. Regardless of the number of homogenization passes, the emulsions exhibited low apparent viscosity and pseudoplastic behavior with small yield stress. Viscoelastic behavior was also observed, thus the emulsions were characterized as weak gels. Four homogenization passes were enough to obtain small droplets in the evaluated conditions. Droplet size was not significantly affected by NaCl concentration and pH (p > 0.05). On the other hand, the absolute ζ-potential values significantly decreased and increased upon increased NaCl content and pH, respectively. Regardless of the tested conditions, all emulsions had good stability against phase separation and droplet aggregation, since no significant changes in average droplet size were observed throughout storage (p > 0.05). In the presence of NaCl, in which droplet charge significantly decreased, emulsion was also stable. Thus, we can conclude that electrostatic repulsion as well as steric repulsion was responsible for stabilization. 相似文献
45.
Jana Durisova 《皮革科学与工程》2006,16(4):3-6
该文研究内底革的实用性,尤其是用于工作靴的内底。因为该类鞋用于条件恶劣的环境,要求穿着舒适,利于健康。重要的两方面是:环境卫生性能和关于明确的肌肉运动体系的物理性能。人们的脚每天频繁运动,容易失水且使表面硬化,如果鞋内底能解决此问题则是既耗费低又简单的方法。对各种材料的内底进行检测发现能承受最大撞击力的材料是硅内底和胶原填充内底。 相似文献
46.
Francisco J. Callado-Muñoz Jana Hromcová Natalia Utrero-González 《Computational Economics》2014,43(4):497-519
We study the relationship between openness and payment system development. In particular, we analyze how the existence of technology diffusion from a more developed country fosters a transformation of payment choice in a less developed country. We apply our analysis to Mexico. Economic growth in Mexico was not high enough to cause a transformation of payment choice observed in the data after 2001. We argue that the switch towards electronic payments can be attributed to openness and related payment technology spillovers from the US in the context of NAFTA. 相似文献
47.
48.
49.
Joost Santos Sheree Ann Pagsuyoin Jana Latayan 《Clean Technologies and Environmental Policy》2016,18(5):1263-1279
Despite significant progress on meeting global water targets, the lack of access to safe drinking water remains a significant problem in today’s world. Statistics from health agencies indicate that waterborne diseases are among the leading causes of health-related mortalities, particularly in developing nations. This paper examines the performance and applicability of various point-of-use (POU) water treatment alternatives, namely (i) solar disinfection; (ii) boiling of water; (iii) chlorination; (iv) disinfection–flocculation with a natural coagulant (powdered Moringa seeds); (v) filtration with ceramic pots; and (vi) biosand filtration. We evaluated the efficacy of each alternative using a set of criteria based on environmental sustainability, technological performance, financial viability, and social acceptability. We also integrated several multi-criteria decision analysis (MCDA) approaches to determine the most suitable water treatment method for a given community. The analytic hierarchy process (AHP) was implemented to elicit various preference structures and to generate the weights for the criteria. Subsequent ranking of the POU alternatives was then performed using the technique for order preference by similarity to ideal solutions (TOPSIS) method. Sensitivity analysis and visualization charts were developed to evaluate the impact of changes in preference ratings of each alternative with respect to the criteria. A case study was implemented in a rural area in the Philippines to determine the optimal POU alternatives given variations in AHP and TOPSIS input data. The resulting MCDA framework is flexible and can accommodate the inclusion of other alternatives and criteria, and it can also be generalized for other regions and applications. 相似文献
50.
Design optimization of deep groove ball bearings using crowding distance particle swarm optimization
This paper presents a crowding distance particle swarm optimization technique to optimize the design parameters of deep groove ball bearings. The design optimization problem is multi-objective in nature. The considered objectives are maximizing dynamic and static load bearing capacities and minimizing elasto-hydrodynamic film thickness. The technique is applied to bearings used in transmission system of a tractor for the purpose of farming. Pareto optimal solutions are obtained using the proposed technique. The results obtained from the technique are found to be superior compared with NSGA-II and catalogue values. 相似文献