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排序方式: 共有920条查询结果,搜索用时 93 毫秒
1.
W. B. Doriese K. M. Morgan D. A. Bennett E. V. Denison C. P. Fitzgerald J. W. Fowler J. D. Gard J. P. Hays-Wehle G. C. Hilton K. D. Irwin Y. I. Joe J. A. B. Mates G. C. O’Neil C. D. Reintsema N. O. Robbins D. R. Schmidt D. S. Swetz H. Tatsuno L. R. Vale J. N. Ullom 《Journal of Low Temperature Physics》2016,184(1-2):396-396
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N. D’Souza F. Liu S. Irwin A. Brown I. M. Edmonds D. S. Rickerby 《Oxidation of Metals》2016,85(3-4):369-389
Secondary ion mass spectrometry (SIMS) was used to study the near-surface segregation of sulphur during; (a) the thermal processing stages (diffusion annealing after application of Pt bond coat and after secondary ageing following subsequent deposition of the Y2O3-stabilised ZrO2 top coat) and (b) thermal cycling in the Ni-base superalloy, CMSX4. In the thermal processing stages, an increased segregation of sulphur was observed within the upper regions of the Pt bond coat after diffusion annealing, while following secondary ageing, the sulphur segregation in this layer became heterogeneous with discrete pockets of enrichment (?1 ppm) and regions of depletion (?1 ppm). During thermal cycling, partitioning of sulphur occurred to the Pt-enriched γ′ region characterised by the finger-like morphology, while examination of TBC spalled specimens showed significant depletion of sulphur within the substrate in the vicinity of the surface. The reservoir for sulphur-depletion within the substrate was definitively identified as the Pt-enriched γ′ region. A quantitative method for the calculation of sulphur-segregation at the surface in terms of mono-layers is presented. 相似文献
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简·欧文景观设计事务所 《风景园林》2017,24(3):59-65
<正>切尔西街游乐场位于悉尼市内东雷德福区中心地带,是散布在该区域内的一系列小型公园中的一个。这些公园作为城市的公共区域,在某种程度上犹如戏剧中的配角一般并不夺人眼球,却是城市格局中至关重要的一部分,成为强调道路网络的日常活动空间。附近有更大的公园和游乐场,承载更有活力的 相似文献
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Protein misfolding and aggregation have been considered important in understanding many neurodegenerative diseases and recombinant biopharmaceutical production. Various traditional and modern techniques have been utilized to monitor protein aggregation in vitro and in living cells. Fibril formation, morphology and secondary structure content of amyloidogenic proteins in vitro have been monitored by molecular probes, TEM/AFM, and CD/FTIR analyses, respectively. Protein aggregation in living cells has been qualitatively or quantitatively monitored by numerous molecular folding reporters based on either fluorescent protein or enzyme. Aggregation of a target protein is directly correlated to the changes in fluorescence or enzyme activity of the folding reporter fused to the target protein, which allows non-invasive monitoring aggregation of the target protein in living cells. Advances in the techniques used to monitor protein aggregation in vitro and in living cells have greatly facilitated the understanding of the molecular mechanism of amyloidogenic protein aggregation associated with neurodegenerative diseases, optimizing culture conditions to reduce aggregation of biopharmaceuticals expressed in living cells, and screening of small molecule libraries in the search for protein aggregation inhibitors. 相似文献
7.
Rogério A. Saraiva Edinardo F. F. Matias Henrique D. M. Coutinho José G. M. Costa Heloísa Helena F. Souza Cícera Norma Fernandes João B. T. Rocha Irwin R. A. Menezes 《European Journal of Lipid Science and Technology》2011,113(8):967-972
The oil obtained from the Caryocar coriaceum Wittm. (pequi) fruit pulp (C. coriaceum fixed oil – CCFO), rich in fatty acids, has been secularly employed by traditional medicine in the treatment of respiratory affections, skin inflammation, and wounds. These observations encouraged us to investigate the antimicrobial activity of CCFO and to investigate its effect in combination with aminoglycosides. The minimum inhibitory concentration (MIC) of CCFO alone and associated with aminoglycosides against Escherichia coli and Staphylococcus aureus strains were determined using microdilution assay. CCFO alone had a MIC of 512 µg/mL against E. coli and S. aureus resistant strains. Combining the CCFO with aminoglycosides reduced the MIC of aminoglycosides against the resistant strains of E. coli and S. aureus. The results obtained indicate that CCFO displays a significant synergistic antibiotic effect when combined with aminoglycosides, demonstrating that the oil constituents (fatty acids) may act as potentiators of the antibiotic activity of aminoglycosides. These properties make CCFO oil an interesting alternative as a remedy or nutraceutical against multiresistant bacteria, preventing the development of resistance by these microorganisms. Practical applications: This article demonstrates the capacity of the C. coriaceum oil to enhance the antibiotic activity of aminoglycosides. This activity could represent a new way to combat the growing bacterial resistance to antibiotics, an important problem of public health. 相似文献
8.
Cihangir Çelik Kenan ÜnlüVijaykrishnan Narayanan Mary J. Irwin 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,652(1):370-373
Soft errors are transient errors caused due to excess charge carriers induced primarily by external radiations in the semiconductor devices. Soft error phenomena could be used to detect thermal neutrons with a neutron monitoring/detection system by enhancing soft error occurrences in the memory devices. This way, one can convert all semiconductor memory devices into neutron detection systems. Such a device is being developed at The Pennsylvania State University and named Neutron Intercepting Silicon Chip (NISC). The NISC is envisioning a miniature, power efficient, and active/passive operation neutron sensor/detector system. NISC aims to achieve this goal by introducing 10B-enriched Borophosphosilicate Glass (BPSG) insulation layers in the semiconductor memories. In order to model and analyze the NISC, an analysis tool using Geant4 as the transport and tracking engine is developed for the simulation of the charged particle interactions in the semiconductor memory model, named NISC Soft Error Analysis Tool (NISCSAT). A simple model with 10B-enriched layer on top of the lumped silicon region is developed in order to represent the semiconductor memory node. Soft error probability calculations were performed via the NISCSAT with both single node and array configurations to investigate device scaling by using different node dimensions in the model. Mono-energetic, mono-directional thermal and fast neutrons are used as the neutron sources. Soft error contribution due to the BPSG layer is also investigated with different 10B contents and the results are presented in this paper. 相似文献
9.
Lahey Benjamin B.; Rathouz Paul J.; Lee Steve S.; Chronis-Tuscano Andrea; Pelham William E.; Waldman Irwin D.; Cook Edwin H. 《Canadian Metallurgical Quarterly》2011,120(1):33
Mounting evidence suggests that genetic risks for mental disorders often interact with the social environment, but most studies still ignore environmental moderation of genetic influences. The authors tested interactions between maternal parenting and the variable number tandem repeat (VNTR) polymorphism in the 3′ untranslated region of the dopamine transporter gene in the child to increase understanding of gene–environment interactions involving early parenting. Participants were part of a 9-year longitudinal study of 4- to 6-year-old children who met criteria for attention-deficit/hyperactivity disorder (ADHD) and demographically matched controls. Maternal parenting was observed during standard mother–child interactions in Wave 1. The child's conduct disorder (CD) symptoms 5–8 years later were measured using separate structured diagnostic interviews of the mother and youth. Controlling for ADHD symptoms and child disruptive behavior during the mother–child interaction, there was a significant inverse relation between levels of both positive and negative parenting at 4–6 years and the number of later CD symptoms, but primarily among children with 2 copies of the 9-repeat allele of the VNTR. The significant interaction with negative parenting was replicated in parent and youth reports of CD symptoms separately. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
B.T. Wittbrodt A.G. Glover J. Laureto G.C. Anzalone D. Oppliger J.L. Irwin J.M. Pearce 《Mechatronics》2013,23(6):713-726
The recent development of open-source 3-D printers makes scaling of distributed additive-based manufacturing of high-value objects technically feasible and offers the potential for widespread proliferation of mechatronics education and participation. These self-replicating rapid prototypers (RepRaps) can manufacture approximately half of their own parts from sequential fused deposition of polymer feedstocks. RepRaps have been demonstrated for conventional prototyping and engineering, customizing scientific equipment, and appropriate technology-related manufacturing for sustainable development. However, in order for this technology to proliferate like 2-D electronic printers have, it must be economically viable for a typical household. This study reports on the life-cycle economic analysis (LCEA) of RepRap technology for an average US household. A new low-cost RepRap is described and the costs of materials and time to construct it are quantified. The economic costs of a selection of 20 open-source printable designs (representing less than 0.02% of those available), are typical of products that a household might purchase, are quantified for print time, energy, and filament consumption and compared to low and high Internet market prices for similar products without shipping costs. The results show that even making the extremely conservative assumption that the household would only use the printer to make the selected 20 products a year the avoided purchase cost savings would range from about $300 to $2000/year. Assuming the 25 h of necessary printing for the selected products is evenly distributed throughout the year these savings provide a simple payback time for the RepRap in 4 months to 2 years and provide an ROI between >200% and >40%. As both upgrades and the components that are most likely to wear out in the RepRap can be printed and thus the lifetime of the distributing manufacturing can be substantially increased the unavoidable conclusion from this study is that the RepRap is an economically attractive investment for the average US household already. It appears clear that as RepRaps improve in reliability, continue to decline in cost and both the number and assumed utility of open-source designs continues growing exponentially, open-source 3-D printers will become a mass-market mechatronic device. 相似文献