全文获取类型
收费全文 | 847篇 |
免费 | 58篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 3篇 |
综合类 | 1篇 |
化学工业 | 204篇 |
金属工艺 | 17篇 |
机械仪表 | 21篇 |
建筑科学 | 51篇 |
矿业工程 | 1篇 |
能源动力 | 34篇 |
轻工业 | 61篇 |
水利工程 | 4篇 |
石油天然气 | 1篇 |
无线电 | 89篇 |
一般工业技术 | 157篇 |
冶金工业 | 80篇 |
原子能技术 | 4篇 |
自动化技术 | 178篇 |
出版年
2024年 | 2篇 |
2023年 | 7篇 |
2022年 | 22篇 |
2021年 | 28篇 |
2020年 | 20篇 |
2019年 | 21篇 |
2018年 | 22篇 |
2017年 | 32篇 |
2016年 | 52篇 |
2015年 | 27篇 |
2014年 | 39篇 |
2013年 | 62篇 |
2012年 | 52篇 |
2011年 | 60篇 |
2010年 | 48篇 |
2009年 | 48篇 |
2008年 | 43篇 |
2007年 | 40篇 |
2006年 | 25篇 |
2005年 | 22篇 |
2004年 | 21篇 |
2003年 | 27篇 |
2002年 | 13篇 |
2001年 | 7篇 |
2000年 | 7篇 |
1999年 | 8篇 |
1998年 | 24篇 |
1997年 | 22篇 |
1996年 | 18篇 |
1995年 | 8篇 |
1994年 | 8篇 |
1993年 | 8篇 |
1992年 | 10篇 |
1991年 | 3篇 |
1990年 | 6篇 |
1989年 | 3篇 |
1986年 | 2篇 |
1985年 | 3篇 |
1984年 | 2篇 |
1983年 | 4篇 |
1982年 | 2篇 |
1981年 | 9篇 |
1980年 | 2篇 |
1979年 | 3篇 |
1978年 | 1篇 |
1977年 | 5篇 |
1976年 | 1篇 |
1975年 | 4篇 |
1973年 | 1篇 |
1954年 | 1篇 |
排序方式: 共有906条查询结果,搜索用时 15 毫秒
41.
Xavier Vanhoye Alexandre Janin Amandine Caillaud Antoine Rimbert Fabienne Venet Morgane Gossez Wieneke Dijk Oriane Marmontel Sverine Nony Charlotte Chatelain Christine Durand Pierre Lindenbaum Jennifer Rieusset Bertrand Cariou Philippe Moulin Mathilde Di Filippo 《International journal of molecular sciences》2022,23(8)
Hypobetalipoproteinemia is characterized by LDL-cholesterol and apolipoprotein B (apoB) plasma levels below the fifth percentile for age and sex. Familial hypobetalipoproteinemia (FHBL) is mostly caused by premature termination codons in the APOB gene, a condition associated with fatty liver and steatohepatitis. Nevertheless, many families with a FHBL phenotype carry APOB missense variants of uncertain significance (VUS). We here aimed to develop a proof-of-principle experiment to assess the pathogenicity of VUS using the genome editing of human liver cells. We identified a novel heterozygous APOB-VUS (p.Leu351Arg), in a FHBL family. We generated APOB knock-out (KO) and APOB-p.Leu351Arg knock-in Huh7 cells using CRISPR-Cas9 technology and studied the APOB expression, synthesis and secretion by digital droplet PCR and ELISA quantification. The APOB expression was decreased by 70% in the heterozygous APOB-KO cells and almost abolished in the homozygous-KO cells, with a consistent decrease in apoB production and secretion. The APOB-p.Leu351Arg homozygous cells presented with a 40% decreased APOB expression and undetectable apoB levels in cellular extracts and supernatant. Thus, the p.Leu351Arg affected the apoB secretion, which led us to classify this new variant as likely pathogenic and to set up a hepatic follow-up in this family. Therefore, the functional assessment of APOB-missense variants, using gene-editing technologies, will lead to improvements in the molecular diagnosis of FHBL and the personalized follow-up of these patients. 相似文献
42.
The initial fretting damage in a glass/PMMA contact was investigated by means of experiments and numerical (F.E.M.) simulations. Both micro-crack nucleation at the contact edges and particle detachment were identified on the PMMA's surface. Micro-crack initiation was related to the combination of high tensile stresses and positive hydrostatic pressures which are known to enhance crazing. During the early stages of the fretting tests, the distribution of the detached particles within the contact was correlated to the spatial distribution of the cumulative interfacial energy dissipated by friction. As the number of cycles was increased, it was observed that detached particles moved toward the middle of the contact. On the basis of FEM simulations, this particle displacement within the contact was attributed to the existence of differential micro-displacements during the fretting cycle. 相似文献
43.
Characterization of activated sludge flocs by confocal laser scanning microscopy and image analysis 总被引:7,自引:0,他引:7
Schmid M Thill A Purkhold U Walcher M Bottero JY Ginestet P Nielsen PH Wuertz S Wagner M 《Water research》2003,37(9):2043-2052
In this study we present a new approach to determine volumes, heterogeneity factors, and compositions of the bacterial population of activated sludge flocs by 3D confocal imaging. After staining the fresh flocs with fluorescein-isothiocyanate, 75 stacks of images (containing approx. 3000 flocs) were acquired with a confocal laser scanning microscope. The self-developed macro 3D volume and surface determination for the KS 400 software package combined the images of one stack to a 3D image and calculated the real floc volume and surface. We determined heterogeneity factors like the ratio of real floc surface to the surface of a sphere with the respective volume and the fractal dimension (D(f)). According to their significant influence on floc integrity and quality, we also investigated the chemical composition of flocs and quantified their bacterial population structure by using group-specific rRNA-targeted probes for fluorescence in situ hybridization. By a settling experiment we enriched flocs with poor settling properties and determined the above-mentioned parameters. This approach revealed shifts in floc volume, heterogeneity, and bacterial and chemical composition according to the settling quality of the flocs. 相似文献
44.
Antoine Diguet Maël Le Berre Yong Chen Damien Baigl 《Small (Weinheim an der Bergstrasse, Germany)》2009,5(14):1661-1666
By dragging a phospholipid solution on microstructured silicon surfaces, phospholipid molecules are selectively deposited inside the microstructures to get regular phospholipid multilayer patterns of controlled thickness over a large scale (~cm2). By varying the dragging speed, the thickness of the patterns varies between 28 and 100 nm on average (7 to 25 bilayers). Electroswelling of phospholipid multilayer patterns leads to the formation of giant liposomes of controlled size and narrow size distributions. 相似文献
45.
Antoine B. Rauzy 《Reliability Engineering & System Safety》2011,96(7):785-792
A large attention has been focused on the Dynamic Fault Trees in the past few years. By adding new gates to static (regular) Fault Trees, Dynamic Fault Trees aim to take into account dependencies among events. Merle et al. proposed recently an algebraic framework to give a formal interpretation to these gates.In this article, we extend Merle et al.'s work by adopting a slightly different perspective. We introduce Sequence Algebras that can be seen as Algebras of Basic Events, representing failures of non-repairable components. We show how to interpret Dynamic Fault Trees within this framework. Finally, we propose a new data structure to encode sets of sequences of Basic Events: Sequence Decision Diagrams. Sequence Decision Diagrams are very much inspired from Minato's Zero-Suppressed Binary Decision Diagrams. We show that all operations of Sequence Algebras can be performed on this data structure. 相似文献
46.
Cécile Pagnoux Nicolas Tessier-Doyen Antoine Pringuet Manuella Cerbelaud Pascual Garcia-Perez 《Journal of the European Ceramic Society》2009,29(8):1379-1385
A process of granulation by a colloidal method based on ceramic powder agglomeration makes it possible to produce millimetric spheres with a very homogeneous distribution in terms of shape and size. The starting suspension consists of a mixture of alumina submicrometer particles and silica nanoparticles such as mSiO2/mAl2O3 = 1.1%. Heterocoagulation between the two oxides occurs forming a flocculated network the structure of which can be modified by a shear application. The outer appearance of the spheres is nearly perfect whereas the inner structure exhibits some defects (cracks and porosity). It has been shown that the green spheres are more porous as well as the grains of the starting suspension are less flocculated. During the drying step, the high mobility of these agglomerates increases the overall density on the surface and leads to the formation of a spherical empty cavity in the sphere centre. 相似文献
47.
48.
Antoine Debuigne Marie HurtgenChristophe Detrembleur Christine JérômeChristopher Barner-Kowollik Thomas Junkers 《Progress in Polymer Science》2012,37(7):1004-1030
The current review focuses on the relevance and practical benefit of interpolymer radical coupling methods. The latter are developing rapidly and constitute a perfectly complementary macromolecular engineering toolbox to the controlled radical polymerization techniques (CRP). Indeed, all structures formed by CRP are likely to be prone to radical coupling reactions, which multiply the available synthetic possibilities. Basically, the coupling systems can be divided in two main categories. The first one, including the atom transfer radical coupling (ATRC), silane radical atom abstraction (SRAA) and cobalt-mediated radical coupling (CMRC), relies on the recombination of macroradicals produced from a dormant species. The second one, including atom transfer nitroxide radical coupling (ATNRC), single electron transfer nitroxide radical coupling (SETNRC), enhanced spin capturing polymerization (ESCP) and nitrone/nitroso mediated radical coupling (NMRC), makes use of a radical scavenger in order to promote the conjugation of the polymer chains. More than a compilation of macromolecular engineering achievements, the present review additionally aims to emphasize the particularities, synthetic potential and present limitations of each system. 相似文献
49.
This paper proposes an original numerical method and studies its performance for solving high-frequency scattering problems involving elongated scatterers. The approach is based on coupling a high-order Padé-type non-reflecting boundary condition with plane wave finite element formulations. It is shown that for some numerical examples the approximate solution of suitable accuracy can be obtained using a small number of degrees of freedom. 相似文献
50.