全文获取类型
收费全文 | 276篇 |
免费 | 16篇 |
专业分类
电工技术 | 15篇 |
化学工业 | 33篇 |
金属工艺 | 12篇 |
机械仪表 | 4篇 |
建筑科学 | 17篇 |
轻工业 | 42篇 |
石油天然气 | 2篇 |
无线电 | 19篇 |
一般工业技术 | 31篇 |
冶金工业 | 104篇 |
自动化技术 | 13篇 |
出版年
2022年 | 4篇 |
2021年 | 2篇 |
2017年 | 6篇 |
2016年 | 10篇 |
2015年 | 7篇 |
2014年 | 4篇 |
2013年 | 7篇 |
2012年 | 15篇 |
2011年 | 12篇 |
2010年 | 9篇 |
2009年 | 8篇 |
2008年 | 8篇 |
2007年 | 7篇 |
2006年 | 9篇 |
2005年 | 8篇 |
2004年 | 6篇 |
2003年 | 5篇 |
2002年 | 3篇 |
2001年 | 5篇 |
2000年 | 4篇 |
1999年 | 13篇 |
1998年 | 23篇 |
1997年 | 16篇 |
1996年 | 9篇 |
1995年 | 11篇 |
1994年 | 8篇 |
1993年 | 7篇 |
1992年 | 1篇 |
1991年 | 3篇 |
1990年 | 1篇 |
1989年 | 3篇 |
1988年 | 3篇 |
1987年 | 5篇 |
1986年 | 5篇 |
1985年 | 2篇 |
1984年 | 4篇 |
1983年 | 4篇 |
1982年 | 2篇 |
1981年 | 3篇 |
1979年 | 3篇 |
1978年 | 2篇 |
1977年 | 7篇 |
1976年 | 5篇 |
1975年 | 2篇 |
1974年 | 2篇 |
1972年 | 2篇 |
1971年 | 1篇 |
1970年 | 2篇 |
1967年 | 1篇 |
1957年 | 1篇 |
排序方式: 共有292条查询结果,搜索用时 15 毫秒
1.
Jianxin Wei Mark R Pickering Michael R Frater John F Arnold John A Boman Wenjun Zeng 《IEEE transactions on image processing》2005,14(8):1033-1042
It is well known that tile-boundary artifacts occur in wavelet-based lossy image coding. However, until now, their cause has not been understood well. In this paper, we show that boundary artifacts are an inescapable consequence of the usual methods used to choose tile size and the type of symmetric extension employed in a wavelet-based image decomposition system. This paper presents a novel method for reducing these tile-boundary artifacts. The method employs odd tile sizes (2N + 1 samples) rather than the conventional even tile sizes (2N samples). It is shown that, for the same bit rate, an image compressed using an odd tile length low-pass first (OTLPF) convention has significantly less boundary artifacts than an image compressed using even tile sizes. The OTLPF convention can also be incorporated into the JPEG 2000 image compression algorithm using extensions defined in Part 2 of this standard. 相似文献
2.
Gathercole Susan E.; Pickering Susan J.; Ambridge Benjamin; Wearing Hannah 《Canadian Metallurgical Quarterly》2004,40(2):177
The structure of working memory and its development across the childhood years were investigated in children 4-15 years of age. The children were given multiple assessments of each component of the A. D. Baddeley and G. Hitch (1974) working memory model. Broadly similar linear functions characterized performance on all measures as a function of age. From 6 years onward, a model consisting of 3 distinct but correlated factors corresponding to the working memory model provided a good fit to the data. The results indicate that the basic modular structure of working memory is present from 6 years of age and possibly earlier, with each component undergoing sizable expansion in functional capacity throughout the early and middle school years to adolescence. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
3.
4.
5.
6.
Favour Felix-Ilemhenbhio George A. E. Pickering Endre Kiss-Toth Jeremy Mark Wilkinson 《International journal of molecular sciences》2022,23(13)
The term heterotopic ossification (HO) describes bone formation in tissues where bone is normally not present. Musculoskeletal trauma induces signalling events that in turn trigger cells, probably of mesenchymal origin, to differentiate into bone. The aetiology of HO includes extremely rare but severe, generalised and fatal monogenic forms of the disease; and as a common complex disorder in response to musculoskeletal, neurological or burn trauma. The resulting bone forms through a combination of endochondral and intramembranous ossification, depending on the aetiology, initiating stimulus and affected tissue. Given the heterogeneity of the disease, many cell types and biological pathways have been studied in efforts to find effective therapeutic strategies for the disorder. Cells of mesenchymal, haematopoietic and neuroectodermal lineages have all been implicated in the pathogenesis of HO, and the emerging dominant signalling pathways are thought to occur through the bone morphogenetic proteins (BMP), mammalian target of rapamycin (mTOR), and retinoic acid receptor pathways. Increased understanding of these disease mechanisms has resulted in the emergence of several novel investigational therapeutic avenues, including palovarotene and other retinoic acid receptor agonists and activin A inhibitors that target both canonical and non-canonical signalling downstream of the BMP type 1 receptor. In this article we aim to illustrate the key cellular and molecular mechanisms involved in the pathogenesis of HO and outline recent advances in emerging molecular therapies to treat and prevent HO that have had early success in the monogenic disease and are currently being explored in the common complex forms of HO. 相似文献
7.
Transient thermography is commonly used for the detection of disbonds in thermal barrier coatings (TBC). As for other NDT techniques, reference test specimens are required for calibration, but unfortunately, real disbonds are very difficult to use because it is difficult to control their size, and large ones tend to spall. Flat bottomed holes are commonly used, but these over-estimate the thermal contrast obtained for a defect of a given diameter. This paper quantifies the differences in thermal response using finite element analysis validated by experiments, and proposes a form of artificial disbond that gives a better representation of the thermal responses seen with real defects. Real disbonds tend to have a non-uniform gap between the disbonded surfaces across the defect, and the effect of this on the thermal response is evaluated using finite element simulations. It is shown that the effect can be compensated for by adjusting the diameter of the calibration defect compared to the real defect. 相似文献
8.
Nicole J. Gaudette Gary J. Pickering 《Critical reviews in food science and nutrition》2013,53(5):464-481
The functional foods sector represents a significant and growing portion of the food industry, yet formulation of these products often involves the use of ingredients that elicit less than desirable oral sensations, including bitterness. Promising new functional ingredients, including polyphenolics, may be more widely and readily employed in the creation of novel functional foods if their aversive bitter taste can be significantly reduced. A number of approaches are used by the industry to improve the taste properties and thus the acceptance of conventional foods that elicit excessive bitterness. This article reviews the most commonly employed techniques, including the use of bitter-modifying additives, which may prove useful for successfully introducing new functional ingredients into this rapidly growing sector. 相似文献
9.
Hemp fibre was treated using a chelator (ethylene diamine tetra methylene phosphonic acid pentasodium salt) and white rot fungi Schizophyllum commune (S.com) with the purpose of improving its interfacial bonding with a polypropylene matrix. Composites were produced by film-stacking long fibre, oriented by carding, with polypropylene (PP) and maleated polypropylene (MAPP) coupling agent. The fibre and composite densities, composite fibre and void contents, as well as fibre and composite tensile strength were analysed. Tensile strength of treated fibre composites was higher than that for untreated fibre composites, despite fibre strength reducing with treatments. This supports that interfacial bonding between hemp and PP was improved by treatment. This trend was also obtained using a modification of the simple “rule of mixtures” model taking account of voids, suggesting that this could be an appropriate means of simply modelling interfacial modification. 相似文献
10.
BS Nielsen TG Banke A Schousboe DS Pickering 《Canadian Metallurgical Quarterly》1998,360(2-3):227-238
Homomeric and heteromeric alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) receptor subunits GluR1o and GluR3o were expressed in Spodoptera frugiperda (Sf9) insect cells. Membranes containing the recombinant receptors showed a doublet of bands of the expected size (99-109 kDa) after western immunoblotting which was shifted to a single band upon deglycosylation. In (R,S)-[3H]AMPA binding experiments, high expression was seen (Bmax = 0.8-3.8 pmol/mg protein) along with high affinity binding to a single site (Kd, nM+/-S.D.): GluR1o, 32.5+/-2.7; GluR3o, 23.7+/-2.4; GluR1o + GluR3o, 18.1+/-2.9. The pharmacological profiles of these receptors resembled that of native rat brain AMPA receptors: AMPA analogues > L-glutamate > quinoxaline-2,3-diones > kainate. In the Xenopus oocyte expression system we had previously shown that the agonist (R,S)-2-amino-3-(3-carboxy-5-methyl-4-isoxazolyl)propionate (ACPA) exhibited an 11-fold selectivity for GluR3o vs. GluR1o. In this study, it was found that ACPA has 3-fold higher affinity at homomeric GluR3o and heteromeric receptors than at homomeric GluR1o, suggesting that its efficacy and/or desensitisation properties are different at GluR1o vs. GluR3o. 相似文献