全文获取类型
收费全文 | 429篇 |
免费 | 33篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 7篇 |
化学工业 | 104篇 |
金属工艺 | 13篇 |
机械仪表 | 9篇 |
建筑科学 | 16篇 |
能源动力 | 23篇 |
轻工业 | 66篇 |
水利工程 | 4篇 |
石油天然气 | 1篇 |
无线电 | 14篇 |
一般工业技术 | 68篇 |
冶金工业 | 89篇 |
原子能技术 | 3篇 |
自动化技术 | 47篇 |
出版年
2023年 | 2篇 |
2022年 | 6篇 |
2021年 | 13篇 |
2020年 | 8篇 |
2019年 | 6篇 |
2018年 | 18篇 |
2017年 | 21篇 |
2016年 | 14篇 |
2015年 | 14篇 |
2014年 | 21篇 |
2013年 | 31篇 |
2012年 | 18篇 |
2011年 | 22篇 |
2010年 | 29篇 |
2009年 | 23篇 |
2008年 | 19篇 |
2007年 | 20篇 |
2006年 | 16篇 |
2005年 | 12篇 |
2004年 | 8篇 |
2003年 | 10篇 |
2002年 | 12篇 |
2001年 | 7篇 |
2000年 | 5篇 |
1999年 | 9篇 |
1998年 | 24篇 |
1997年 | 23篇 |
1996年 | 18篇 |
1995年 | 6篇 |
1994年 | 5篇 |
1993年 | 5篇 |
1992年 | 1篇 |
1991年 | 4篇 |
1990年 | 2篇 |
1989年 | 4篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1980年 | 1篇 |
1977年 | 1篇 |
1976年 | 2篇 |
排序方式: 共有464条查询结果,搜索用时 234 毫秒
81.
82.
de Fuentes Jose M. Gonzalez-Manzano Lorena Lopez Javier Peris-Lopez Pedro Choo Kim-Kwang Raymond 《Mobile Networks and Applications》2019,24(3):878-880
Mobile Networks and Applications - 相似文献
83.
Eric C. O’Quinn Jessica L. Bishop Roman Sherrod Joerg Neuefeind Sagrario M. Montemayor Antonio F. Fuentes Maik Lang 《Journal of Materials Science》2018,53(19):13400-13410
Materials that adopt the pyrochlore (A2B2O7) structure show promise for use in a variety of energy-related applications such as immobilization of actinide-rich nuclear waste and oxide fuel cells. Mechanochemical synthesis, a combination of milling and high-temperature treatment, has been successfully applied to fabricate many different pyrochlore compositions. High-resolution neutron total scattering experiments were used to gain fundamental insight into the structural details of milled Er2Ti2O7 pyrochlore and the subsequent evolution under high-temperature treatment. The milling process creates a highly disordered structure in which local atomic ordering is present that is significantly different than the observed long-range behavior. Thermal annealing leads to a complex defect recovery scheme with a gradual local rearrangement from a weberite-type atomic ordering to a pyrochlore phase independent of the sharp long-range crystallization process. Annealing of the milled sample up to 1200 °C does not reproduce the local structure of the same pyrochlore sample prepared by solid-state synthesis. This indicates that despite both samples possessing identical long-range structures, local defects induced by the milling process persist to very high temperatures. These findings provide a direct insight into the mechanochemical synthesis of pyrochlore oxides and help to better elucidate the structural properties of highly disordered complex oxides under extreme conditions from the local atomic arrangement to the macroscale. 相似文献
84.
On the use of British standard 7910 option 1 failure assessment diagram to non‐metallic materials 下载免费PDF全文
J.D. Fuentes S. Cicero F.T. Ibáñez‐Gutiérrez I. Procopio 《Fatigue & Fracture of Engineering Materials & Structures》2018,41(1):146-158
This paper provides a structural integrity assessment methodology for the analysis of non‐metallic materials. The approach uses the British standard 7910 option 1 failure assessment diagram, originally proposed for the fracture‐plastic collapse assessment of metallic materials. The methodology has been applied to 60 fracture specimens, combining 12 different materials and covering polymers, composites, and rocks. The results obtained validate the proposed assessment methodology and demonstrate its safety for the materials analysed here. 相似文献
85.
Lewis Hyland Andy Crabtree Joel Fischer James Colley Carolina Fuentes 《Computer Supported Cooperative Work (CSCW)》2018,27(3-6):917-946
This paper examines ‘the routine shop’ as part of a project that is exploring automation and autonomy in the Internet of Things. In particular we explicate the ‘work’ involved in anticipating need using an ethnomethodological analysis that makes visible the mundane, ‘seen but unnoticed’ methodologies that household members accountably employ to organise list construction and accomplish calculation on the shop floor. We discuss and reflect on the challenges members’ methodologies pose for proactive systems that seek to support domestic grocery shopping, including the challenges of sensing, learning and predicting, and gearing autonomous agents into social practice within the home. 相似文献
86.
Michael C.J. Bradford Mure Te Mahesh V. Konduru Allen Pollack Digna X. Fuentes 《Catalysis Today》2007,123(1-4):23
A multi-step process that employs a Ni-modified mixed alkaline earth metal oxides (AEMO) has been developed for the selective conversion of hydrocarbons to C2H2 and CO. The initial process step is the catalytic decomposition of a gaseous hydrocarbon mixture at an elevated temperature (ca. 800 °C) over Ni/AEMO, generating H2, trace CO, carbon (C), and trace alkaline earth metal carbide (MC2). The Ni/AEMO/C/MC2 material is then heated to consume the remaining carbon, generate more MC2, and evolve CO. Then, Ni/AEMO/MC2 is cooled and reacted with excess H2O at a low temperature (20 < T (°C) < 80) to selectively generate C2H2 and Ni/AEM(OH)2·zH2O. In the final process step, Ni/AEM(OH)2·zH2O is decomposed to yield H2O and Ni/AEMO, which is recycled within the process. The most advanced Ni/AEMO materials developed thus far exhibit intrinsic production capacities exceeding 2000 μmoles of C2H2 per gram of Ni/AEMO per process cycle. 相似文献
87.
Among other special characteristics Shape Memory Alloys (SMAs) have the ability to return to a predetermined shape when heated. In fact, the phase change of an existing element can strongly be influenced by thermal and thermo‐mechanical treatments. Up to now, SMEs have been discovered in various materials, which can generally be classified into noble‐metal based, Cu‐based, Fe‐based, Ni‐Ti‐based alloy systems and non‐metallic SMAs. In this paper a general overview of the Ni‐Ti system and a detailed review over the Ni‐Ti‐Cu system will be given with special regard to the influence of heat treatments upon the phase change behavior. 相似文献
88.
Ana Santos-Gmez Federico Miguez-Cabello Natalia Juli-Palacios Deyanira García-Navas Víctor Soto-Insuga Juan J. García-Peas Patricia Fuentes Salvador Ibez-Mic Laura Cuesta Ramn Cancho Patricia Andreo-Lillo Gema Gutirrez-Aguilar Olga Alonso-Luengo Ignacio Mlaga Antonio Hedrera-Fernndez ngels García-Cazorla David Soto Mireia Olivella Xavier Altafaj 《International journal of molecular sciences》2021,22(23)
Background: GRIN-related disorders (GRD), the so-called grinpathies, is a group of rare encephalopathies caused by mutations affecting GRIN genes (mostly GRIN1, GRIN2A and GRIN2B genes), which encode for the GluN subunit of the N-methyl D-aspartate (NMDA) type ionotropic glutamate receptors. A growing number of functional studies indicate that GRIN-encoded GluN1 subunit disturbances can be dichotomically classified into gain- and loss-of-function, although intermediate complex scenarios are often present. Methods: In this study, we aimed to delineate the structural and functional alterations of GRIN1 disease-associated variants, and their correlations with clinical symptoms in a Spanish cohort of 15 paediatric encephalopathy patients harbouring these variants. Results: Patients harbouring GRIN1 disease-associated variants have been clinically deeply-phenotyped. Further, using computational and in vitro approaches, we identified different critical checkpoints affecting GluN1 biogenesis (protein stability, subunit assembly and surface trafficking) and/or NMDAR biophysical properties, and their association with GRD clinical symptoms. Conclusions: Our findings show a strong correlation between GRIN1 variants-associated structural and functional outcomes. This structural-functional stratification provides relevant insights of genotype-phenotype association, contributing to future precision medicine of GRIN1-related encephalopathies. 相似文献
89.
Sánchez-Ramírez JF Jiménez Pérez JL Cruz Orea A Gutierrez Fuentes R Bautista-Hernández A Pal U 《Journal of nanoscience and nanotechnology》2006,6(3):685-690
Colloidal suspensions of bimetallic Au/Pd nanoparticles were prepared by simultaneous reduction of the metal ions from their corresponding chloride salts with polymer (PVP) stabilizer. Thermal properties of water containing bimetallic nanoparticles with different nominal compositions (Au/Pd = 12/1, 5/1, 1/1, 1/5) were measured using the mode mismatched dual-beam thermal lens technique to determine the effect of particle composition on the thermal diffusivity of the nanofluids. The characteristic time constant of the transient thermal lens was estimated by fitting the experimental data to the theoretical expression for transient thermal lens. The thermal diffusivity of the nanofluids (water, containing Au/Pd bimetallic nanoparticles) is seen to be strongly dependent on the composition of the particles. The maximum diffusivity was achieved for the nanoparticles with highest Au/Pd molar ratio. A possible mechanism for such high thermal diffusivity of the nanofluids with bimetallic particles is given. UV-Vis spectroscopy, TEM and high-resolution electron microscopy (HREM) techniques were used to characterize the Au/Pd bimetallic nanoparticles. 相似文献
90.
Aragón J González R Fuentes G Palin L Croce G Viterbo D 《Journal of materials science. Materials in medicine》2012,23(2):259-270
Coralline calcium-hydroxyapatite and calcium carbonate from Porites Porites coral were added to a polymeric matrix based on polyvinyl acetate (POVIAC?), to obtain a novel bone substitute composite as well as a system for the controlled drug (cephalexin) release. Composite
samples with different compositions were characterized by physical–chemical and mechanical methods. Furthermore, the in vitro
release profile of cephalexin and the kinetic behavior of its release from these composites were analyzed by appropriate mathematical
models. It was shown that there is no chemical interaction between the inorganic filler and the polymer matrix, each conserving
the original properties of the raw materials. The compressive mechanical strength and Young modulus of the composite with
17.5% of POVIAC?, has better mechanical properties than those of cancellous bone. The variation of POVIAC? content can affect the cephalexin release kinetic in the composite. The cephalexin release mechanism from the composites
can be considered as the result of the joint contribution of a prevailing Fickian diffusion and of polymer chain relaxation.
It was also demonstrated that cephalexin is occluded inside the composites and not on their surface. 相似文献