全文获取类型
收费全文 | 162篇 |
免费 | 2篇 |
专业分类
化学工业 | 41篇 |
金属工艺 | 2篇 |
机械仪表 | 2篇 |
建筑科学 | 4篇 |
能源动力 | 11篇 |
轻工业 | 3篇 |
无线电 | 9篇 |
一般工业技术 | 30篇 |
冶金工业 | 29篇 |
自动化技术 | 33篇 |
出版年
2022年 | 2篇 |
2021年 | 3篇 |
2018年 | 2篇 |
2017年 | 2篇 |
2016年 | 7篇 |
2015年 | 4篇 |
2014年 | 2篇 |
2013年 | 8篇 |
2012年 | 4篇 |
2011年 | 11篇 |
2010年 | 3篇 |
2009年 | 5篇 |
2008年 | 6篇 |
2007年 | 4篇 |
2006年 | 5篇 |
2005年 | 8篇 |
2004年 | 4篇 |
2003年 | 2篇 |
2002年 | 4篇 |
2001年 | 2篇 |
2000年 | 2篇 |
1999年 | 3篇 |
1998年 | 8篇 |
1997年 | 9篇 |
1996年 | 8篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 4篇 |
1992年 | 3篇 |
1991年 | 4篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1985年 | 2篇 |
1983年 | 4篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1975年 | 2篇 |
1970年 | 1篇 |
1968年 | 2篇 |
1967年 | 2篇 |
1966年 | 1篇 |
1965年 | 1篇 |
1955年 | 1篇 |
1946年 | 2篇 |
排序方式: 共有164条查询结果,搜索用时 15 毫秒
91.
Multiplex systems are examined in the time and frequency domains for their utility in applications to biological studies. The continuous-wave FM is shown to fit best the requirements of genuine signal reproduction, reasonable construction and reliability. 相似文献
92.
Orna Barash Nir Peled Fred R. Hirsch Hossam Haick 《Small (Weinheim an der Bergstrasse, Germany)》2009,5(22):2618-2624
A highly sensitive and fast‐response array of sensors based on gold nanoparticles, in combination with pattern recognition methods, can distinguish between the odor prints of non‐small‐cell lung cancer and negative controls with 100% accuracy, with no need for preconcentration techniques. Additionally, preliminary results indicate that the same array of sensors might serve as a better tool for understanding the biochemical source of volatile organic compounds that might occur in cancer cells and appear in the exhaled breath, as compared to traditional spectrometry techniques. The reported results provide a launching pad to initiate a bedside tool that might be able to screen for early stages of lung cancer and allow higher cure rates. In addition, such a tool might be used for the immediate diagnosis of fresh (frozen) tissues of lung cancer in operating rooms, where a dichotomic diagnosis is crucial to guide surgeons. 相似文献
93.
A novel approach to the synthesis of a low-cost proton-exchange membrane (PEM) based on the single-step preparation of a functionalized ceramic powder containing surface-anchored sulfonic acid (SASA) and a polymer binder, is presented for the first time. The added value of this technique, compared with earlier work published by our group, is the adoption of a direct, single-step synthesis, as opposed to a multiple-step synthesis. The latter requires an oxidation step, in order to convert the thiol group into a sulfonic group. SASA powders of different compositions have been prepared and characterized by means of Brunaur–Emmet–Teller (BET), thermogravimetric analysis–differential thermal analysis (TGA–DTG), differential scanning calorimeter (DSC), Fourier transformation infrared (FT-IR), nuclear magnetic resonance (NMR), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), scanning electron microscopy (SEM) and electrochemical techniques. The lowest equivalent weight measured for SASA powders is 1281 g equiv.−1. The ionic conductivity of a 100-μm-thick membrane is measured ex situ at room temperature (25 ± 3 °C) and the highest proton conductivity is 48 mS cm−1. The typical pore size, for the SASA powders is less than 10 nm and ranges from 2 to 50 nm for the SASA-based membranes. The membranes are thermally stable up to 250 °C. 相似文献
94.
Pushkar Dolores; Basevitz Paul; Arbuckle Tannis; Nohara-LeClair Michiko; Lapidus Steven; Peled Maya 《Canadian Metallurgical Quarterly》2000,15(2):361
This study investigated social behavior in older adults with varying levels of off-target verbosity (OTV). After screening 455 adults in Phase 1, 198 individuals were selected to participate in both a get-acquainted conversation and an experimental cues situation and to complete social and cognitive measures. Higher OTV participants had lower cognitive inhibitory scores, talked more, were less interested in their partners, and focused more on themselves. Their conversational partners were less satisfied. Age and cognitive functioning were not related to OTV scores or conversational style for low and mid-range participants. Although high-OTV individuals talked less when exposed to social cues signalling boredom, they spoke more relative to other participants. Self-reported social behavior had little relation with OTV and conversational style, but higher OTV individuals were less accurate in judging videotaped social interactions. Gender differences in conversational behavior are also discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
A sorption balance is an instrument used to measure vapor uptake in a sample at controlled temperature and relative humidity. It is most commonly used to determine equilibrium values (sorption isotherms), but is also used for kinetic measurements of transport coefficients. Such measurements can be affected by the external mass transfer resistance in the gas phase around the sample. This paper presents a method to determine the external mass transfer coefficient for a given flow geometry using a water saturated sample, including corrections for temperature changes from evaporative cooling, which is found to have considerable effect on the calculated constant. 相似文献
96.
Analysis of the nucleotide sequence in the 5' flanking region of bacteriophage T4 gene 25 revealed three potential Shine and Dalgarno sequences, SD1, SD2 and SD3, with a spacing of 8, 17 and 27 nucleotides from the initiation codon of this gene, respectively. Results of our experiments in the bacteriophage T7 expression system clearly demonstrate that the SD3 sequence is required for efficient expression of gene 25. We propose the existence of a stem-loop structure that includes SD1 and SD2 sequences and brings the SD3 sequence to a favourable spacing with the initiation codon of gene 25. Since the predicted secondary structure in the translational initiation region of gene 25 is relatively unstable and the SD3 sequence, GAGG, is more typical than the SD1 sequence, GAG, we suggest that this structure could control the level of gene expression. 相似文献
97.
Two Core-Shell, RuCore-PtShell and IrNiCore-PtRuShell, XC72-supported catalyst were synthesized in a two-step deposition process with NaBH4 as reducing agent. The structure and composition of the Core-Shell catalysts were determined by EDS, XPS and XRD. Electrochemical characterization was performed with the use of cyclic voltammetry. Methanol and ethylene glycol oxidation activities of the Core-Shell catalysts (in terms of surface and mass activities) were studied at 80 °C and compared to those of a commercial Pt-Ru alloy catalyst. The surface activity of the alloy based catalyst, in the case of methanol oxidation, was found to be superior as a result of optimized surface Pt:Ru composition. However, the mass activity of the PtRu/IrNi/XC72 was higher than that of the alloy based catalyst by ∼50%. Regarding ethylene glycol oxidation, while the surface activity of the alloy based catalyst was slightly higher than that of the Pt/Ru/XC72 catalyst, the latter showed ∼66% higher activities in terms of A g−1 of Pt. These results show the potential of Core-Shell catalysts for reducing the cost of catalysts for DMFC and DEGFC. 相似文献
98.
99.
100.
Roie Zivan Tomer Parash Liel Cohen Hilla Peled Steven Okamoto 《Autonomous Agents and Multi-Agent Systems》2017,31(5):1165-1207
Distributed Constraint Optimization Problems (DCOPs) are NP-hard and therefore the number of studies that consider incomplete algorithms for solving them is growing. Specifically, the Max-sum algorithm has drawn attention in recent years and has been applied to a number of realistic applications. Unfortunately, in many cases Max-sum does not produce high-quality solutions. More specifically, Max-sum does not converge and explores solutions of low quality when run on problems whose constraint graph representation contains multiple cycles of different sizes. In this paper we advance the state-of-the-art in incomplete algorithms for DCOPs by: (1) proposing a version of the Max-sum algorithm that operates on an alternating directed acyclic graph (Max-sum_AD), which guarantees convergence in linear time; (2) solving a major weakness of Max-sum and Max-sum_AD that causes inconsistent costs/utilities to be propagated and affect the assignment selection, by introducing value propagation to Max-sum_AD (Max-sum_ADVP); and (3) proposing exploration heuristic methods that evidently improve the algorithms performance further. We prove that Max-sum_ADVP converges to monotonically improving states after each change of direction, and that it is guaranteed to converge in pseudo-polynomial time to a stable solution that does not change with further changes of direction. Our empirical study reveals a large improvement in the quality of the solutions produced by Max-sum_ADVP on various benchmarks, compared to the solutions produced by the standard Max-sum algorithm, Bounded Max-sum and Max-sum_AD with no value propagation. It is found to be the best guaranteed convergence inference algorithm for DCOPs. The exploration methods we propose for Max-sum_ADVP improve its performance further. However, anytime results demonstrate that their exploration level is not as efficient as a version of Max-sum, which uses Damping. 相似文献