全文获取类型
收费全文 | 381篇 |
免费 | 45篇 |
专业分类
电工技术 | 6篇 |
化学工业 | 155篇 |
金属工艺 | 1篇 |
机械仪表 | 5篇 |
建筑科学 | 5篇 |
能源动力 | 24篇 |
轻工业 | 74篇 |
水利工程 | 2篇 |
无线电 | 25篇 |
一般工业技术 | 39篇 |
冶金工业 | 52篇 |
自动化技术 | 38篇 |
出版年
2024年 | 1篇 |
2023年 | 10篇 |
2022年 | 22篇 |
2021年 | 21篇 |
2020年 | 7篇 |
2019年 | 11篇 |
2018年 | 15篇 |
2017年 | 16篇 |
2016年 | 13篇 |
2015年 | 8篇 |
2014年 | 22篇 |
2013年 | 29篇 |
2012年 | 17篇 |
2011年 | 30篇 |
2010年 | 21篇 |
2009年 | 16篇 |
2008年 | 18篇 |
2007年 | 19篇 |
2006年 | 12篇 |
2005年 | 12篇 |
2004年 | 14篇 |
2003年 | 9篇 |
2002年 | 6篇 |
2001年 | 4篇 |
2000年 | 9篇 |
1999年 | 6篇 |
1998年 | 10篇 |
1997年 | 12篇 |
1996年 | 6篇 |
1995年 | 4篇 |
1994年 | 2篇 |
1993年 | 2篇 |
1992年 | 1篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 3篇 |
1987年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1979年 | 1篇 |
1976年 | 3篇 |
1974年 | 5篇 |
1973年 | 2篇 |
1972年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有426条查询结果,搜索用时 15 毫秒
101.
Danil W. Boukhvalov Raju Edla Anna Cupolillo Vito Fabio Raman Sankar Yanglin Zhu Zhiqiang Mao Jin Hu Piero Torelli Gennaro Chiarello Luca Ottaviano Antonio Politano 《Advanced functional materials》2019,29(18)
Materials exhibiting nodal‐line fermions promise superb impact on technology for the prospect of dissipationless spintronic devices. Among nodal‐line semimetals, the ZrSiX (X = S, Se, Te) class is the most suitable candidate for such applications. However, the surface chemical reactivity of ZrSiS and ZrSiSe has not been explored yet. Here, by combining different surface‐science tools and density functional theory, it is demonstrated that the formation of ZrSiS and ZrSiSe surfaces by cleavage is accompanied by the washing up of the exotic topological bands, giving rise to the nodal line. Moreover, while the ZrSiS has a termination layer with both Zr and S atoms, in the ZrSiSe surface, reconstruction occurs with the appearance of Si surface atoms, which is particularly prone to oxidation. It is demonstrated that the chemical activity of ZrSiX compounds is mostly determined by the interaction of the Si layer with the ZrX sublayer. A suitable encapsulation for ZrSiX should not only preserve their surfaces from interaction with oxidative species, but also provide a saturation of dangling bonds with minimal distortion of the surface. 相似文献
102.
Junfeng Gao Anna Cupolillo Silvia Nappini Federica Bondino Raju Edla Vito Fabio Raman Sankar Yong‐Wei Zhang Gennaro Chiarello Antonio Politano 《Advanced functional materials》2019,29(26)
Cadmium arsenide (Cd3As2) has recently attracted considerable interest for the presence of 3D massless Dirac fermions with ultrahigh mobility and magnetoresistance. However, its surface properties are currently largely unexplored both theoretically and experimentally, due to the very large unit cell and the challenging growth of single‐crystal samples, respectively. Here, by combining ab initio calculations with surface‐science spectroscopic experiments, the presence of a surface reconstruction is unveiled in centimeter‐scale (112)‐oriented Cd3As2 single‐crystal foils produced by the self‐selecting vapor growth. Outermost Cd atoms descend into the As‐sublayer with a subsequent self‐passivation of the dangling bonds with As atoms, forming the triangle lattice previously imaged by scanning tunneling microscopy. Moreover, the oxidation mechanism of this reconstructed surface, dominated by the formation of As? O? Cd bonds, is revealed. Interestingly, it is found that the band structure of the reconstructed surface of Cd3As2 is quite robust against surface oxidation. Both computational and experimental findings point to a successful exploitation in technology of Cd3As2 single crystals. 相似文献
103.
In the last decades, we have witnessed a growing interest toward touchless gestural user interfaces. Among other reasons, this is due to the large availability of different low‐cost gesture acquisition hardware (the so‐called “Kinect‐like devices”). As a consequence, there is a growing need for solutions that allow to easily integrate such devices within actual systems. In this paper, we present KIND‐DAMA, an open and modular middleware that helps in the development of interactive applications based on gestural input. We first review the existing middlewares for gestural data management. Then, we describe the proposed architecture and compare its features against the existing similar solutions we found in the literature. Finally, we present a set of studies and use cases that show the effectiveness of our proposal in some possible real‐world scenarios. 相似文献
104.
Narges Ataollahi Fabrizio Girardi Elisa Cappelletto Keti Vezzù Vito Di Noto Paolo Scardi Emanuela Callone Rosa Di Maggio 《应用聚合物科学杂志》2017,134(44)
Alternating polyketones constitute a very interesting class of polymers, which can be modified for the preparation of functional polymers. The chemical modification of polyketone using 1,2‐diaminopropane was used to prepare a conductive membrane. This paper is focused on the synthesis and structural rearrangements of polyamine for preparing anion‐exchange membranes by the solvent casting technique. According to the Paal‐Knorr mechanism, 1,4‐dicarbonyl of polyketone reacts with 1,2‐diaminopropane to form a pyrrole ring along the polyketone backbone. In addition, the so‐modified polyamines can undergo structural rearrangements to form N‐substituted pyrrole crosslinked with dihydropyridine units. The conversion degree and the N content are quite low. The pathway reactions have been proposed on the basis of 1H‐NMR, ultraviolet–visible, and Fourier transform infrared results. Scanning electron microscopy, differential scanning calorimetry, and X‐ray diffraction techniques were used to study the morphological, thermal, and structural characteristics of the modified polyketone, as well as the correspondoing membrane. The experimental results indicated that the membrane is a potential candidate for energy conversion technology. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45485. 相似文献
105.
Vito Alunno-Rossetti Gerardo Chiocchio Mario Collepardi 《Cement and Concrete Research》1973,3(6):665-676
Samples of C3s, hydrated at room temperature for 0, 2, 4, 8 and 24 hours, were steam cured at 130, 160 and 190°C for 5, 15 and 24 hours, in order to assess the influence of preliminary curing on autoclave hydration. The room temperature curing duration affects the autoclave hydration of C3S, mainly at low temperatures. The types and relative amounts of the obtained products are also markedly affected by the preliminary treatment. 相似文献
106.
Two nanostructured mixed oxide catalysts (the CoCr2O4 spinel and the LiCrO2 delafossite) have been recently developed for diesel soot combustion. The catalysts have been deposited via in situ combustion synthesis over SiC wallflow trap by CTI (Salindres, F). Bench tests proved that, after soot loading, both the developed traps enable
a faster and more complete regeneration at 550 °C than the non-catalysed trap. However, a specific study on the particles
distribution after the SiC trap, carried out via SMPS analysis, showed that secondary nanoparticles (<20 nm) are emitted during
the regeneration promoted by the highly-active CoCr2O4 catalytic trap, as opposed to the LiCrO2-catalysed and the virgin counter parts. This phenomenon has been investigated vs. the regeneration temperature and some sampling
conditions so as to draw preliminary indications on the nature of these undesired particles. 相似文献
107.
Vito Alunno-Rossetti Gerardo Chiocchio Mario Collepardi 《Cement and Concrete Research》1974,4(2):279-288
Pastes of C3S (w/c ratio = 0.5) were steam cured at 25, 40, 60 and 90°C for 1 hour to 30 days. The results obtained have shown that, as the curing temperature rises, the induction period is shortened and the initial rate of hydration of C3S is increased; at longer curings, on the other hand, such hydration rate is considerably lowered. In order to explain the influence of temperature on the hydration reaction a new hypothesis has been proposed, which takes into account the C/S molar ratio as well as the surface properties of the hydrated silicate. 相似文献
108.
In this paper, the dual representation of spatial parametric curves and its properties are studied. In particular, rational curves have a polynomial dual representation, which turns out to be both theoretically and computationally appropriate to tackle the main goal of the paper: spatial rational Pythagorean-hodograph curves (PH curves). The dual representation of a rational PH curve is generated here by a quaternion polynomial which defines the Euler–Rodrigues frame of a curve. Conditions which imply low degree dual form representation are considered in detail. In particular, a linear quaternion polynomial leads to cubic or reparameterized cubic polynomial PH curves. A quadratic quaternion polynomial generates a wider class of rational PH curves, and perhaps the most useful is the ten-parameter family of cubic rational PH curves, determined here in the closed form. 相似文献
109.
Topics in Catalysis - The soot combustion process, promoted by some promising diesel particulate combustion catalysts based on Cs and V oxides (Cs2O, Cs3VO4, Cs4V2O7, Cs2O · V2O5, CsVO3,... 相似文献
110.
Stefania Bandini Andrea Bonomi Giuseppe Vizzari Vito Acconci 《The Journal of supercomputing》2011,57(2):109-120
The term Ambient Intelligence (AmI) refers to electronic environments that are sensitive and responsive to the presence of
people; in this paper, an example of AmI system whose goal is to enhance the experience of pedestrians moving inside the related
physical environment will be presented. The environment is endowed with a set of sensors (to perceive humans or other physical
entities such as dogs, bicycles, etc.), interacting with a set of actuators (lights). The model for the interaction and action
of sensors and actuators is a dissipative multilayered cellular automata, supporting a self-organization of the system as
a response to the presence and movements of people inside it. The paper will introduce the model, as well as the results of
simulations of its application in a concrete case study. 相似文献