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51.
Maria Cristina Righetti Alessia Boggioni Michele Laus Diego Antonioli Katia Sparnacci Luca Boarino 《应用聚合物科学杂志》2013,130(5):3624-3633
Polyethersulphone/polytetrafluoroethylene (PES/PTFE) nanocomposites and composites were prepared by precipitation of PES into a PTFE latex‐containing nanoparticles. Different samples were obtained by varying the relative ratio between PES and PTFE. The complex crystallization process, discussed within the fractionated crystallization frame, allowed to identify and quantify different dispersion degree of the PTFE nanoparticles within the PES matrix. The different samples were thus divided into nanocomposite and composites. The effect of crystalline PTFE domains on the mobility of PES was investigated and discussed. The dynamic‐mechanical behavior was explained in terms of the particle aggregation state. The mechanical properties of the PES/PTFE composites were found to depend on both the dispersion and the concentration of the PTFE nanoparticles. In the glassy state the stiffness of the materials was found to increase with the dispersion degree, resulting higher for the nanocomposite with respect to composites. On the contrary, in the rubbery state the modulus was found proportional to the PTFE nanoparticles concentration, resulting higher in the composites with respect to the nanocomposite. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3624–3633, 2013 相似文献
52.
Routing for disruption tolerant networks: taxonomy and design 总被引:5,自引:0,他引:5
Thrasyvoulos Spyropoulos Rao Naveed Bin Rais Thierry Turletti Katia Obraczka Athanasios Vasilakos 《Wireless Networks》2010,16(8):2349-2370
Communication networks, whether they are wired or wireless, have traditionally been assumed to be connected at least most
of the time. However, emerging applications such as emergency response, special operations, smart environments, VANETs, etc.
coupled with node heterogeneity and volatile links (e.g. due to wireless propagation phenomena and node mobility) will likely
change the typical conditions under which networks operate. In fact, in such scenarios, networks may be mostly disconnected,
i.e., most of the time, end-to-end paths connecting every node pair do not exist. To cope with frequent, long-lived disconnections,
opportunistic routing techniques have been proposed in which, at every hop, a node decides whether it should forward or store-and-carry a message.
Despite a growing number of such proposals, there still exists little consensus on the most suitable routing algorithm(s)
in this context. One of the reasons is the large diversity of emerging wireless applications and networks exhibiting such
“episodic” connectivity. These networks often have very different characteristics and requirements, making it very difficult,
if not impossible, to design a routing solution that fits all. In this paper, we first break up existing routing strategies
into a small number of common and tunable routing modules (e.g. message replication, coding, etc.), and then show how and when a given routing module should be used, depending on the set of network characteristics exhibited by the wireless application. We further attempt to create a taxonomy for intermittently connected networks. We
try to identify generic network characteristics that are relevant to the routing process (e.g., network density, node heterogeneity, mobility patterns) and dissect different
“challenged” wireless networks or applications based on these characteristics. Our goal is to identify a set of useful design guidelines that will enable one to choose an appropriate routing protocol for the application or network in hand. Finally, to demonstrate
the utility of our approach, we take up some case studies of challenged wireless networks, and validate some of our routing
design principles using simulations. 相似文献
53.
54.
Gian Domenico Sorarù Katia Girardini Masaki Narisawa Mattia Biesuz 《Journal of the American Ceramic Society》2021,104(7):3097-3104
In this study the high temperature stability (crystallization and decomposition) of two silicon oxycarbide glasses with a similar amount of free carbon (8.3 vs 9.6 wt%) but different content of Si-C bonds (SiC0.22O1.57 vs SiC0.07O1.86) is presented. The two SiOC glasses are obtained from the same precursor (2 µm methyl-silsesquioxane spheres) via pyrolysis at 1100°C in inert (Ar) or reactive (CO2) atmospheres. Further annealing in Ar flow at temperatures above 1100°C and up to 1500°C is performed and the samples are characterized by Fourier Transformed Infrared Spectroscopy (FT-IR) and X-ray diffraction (XRD). For comparison purposes the same precursor was annealed in air flow to obtain SiO2 and its high temperature evolution is also studied. Results suggest that the onset for the carbothermal reduction is not dependent on the amount of Si-C bonds. Moreover, contrary to what is usually reported in the scientific literature, silica phase present in the SiOC glasses does not show, in the same experimental conditions, superior crystallization resistance compared to pure silica glass. 相似文献
55.
56.
Kelly Pedrozo Ferreira Bruna Cristine de Almeida Laura Gonzalez dos Anjos Glauco Baiocchi Fernando Augusto Soares Rafael Malagoli Rocha Edmund Chada Baracat Andrey Senos Dobroff Katia Candido Carvalho 《International journal of molecular sciences》2021,22(9)
The role and prognostic value of tetraspanins (TSPANs) in vulvar squamous cell carcinoma (VSCC) remain poorly understood. We sought to primarily determine, at both the molecular and tissue level, the expression profile of the TSPANs CD9, CD63, CD81, and CD82 in archived VSCC samples (n = 117) and further investigate their clinical relevance as prognostic markers. Our studies led us to identify CD63 as the most highly expressed TSPAN, at the gene and protein levels. Multicomparison studies also revealed that the expression of CD9 was associated with tumor size, whereas CD63 upregulation was associated with histological diagnosis and vascular invasion. Moreover, low expression of CD81 and CD82 was associated with worse prognosis. To determine the role of TSPANs in VSCC at the cellular level, we assessed the mRNA levels of CD63 and CD82 in established metastatic (SW962) and non-metastatic (SW954) VSCC human cell lines. CD82 was found to be downregulated in SW962 cells, thus supporting its metastasis suppressor role. However, CD63 was significantly upregulated in both cell lines. Silencing of CD63 by siRNA led to a significant decrease in proliferation of both SW954 and SW962. Furthermore, in SW962 particularly, CD63-siRNA also remarkably inhibited cell migration. Altogether, our data suggest that the differential expression of TSPANs represents an important feature for prognosis of VSCC patients and indicates that CD63 and CD82 are likely potential therapeutic targets in VSCC. 相似文献
57.
Carolina Kymie Vasques Nonaka Gabriela Louise Sampaio Luciana de Arago Frana Bruno Raphael Cavalcante Katia Nunes Silva Ricardo Khouri Felipe Guimares Torres Cassio Santana Meira Emanuelle de Souza Santos Carolina Th Macedo Bruno Diaz Paredes Vinicius Pinto Costa Rocha Silvia Regina Rogatto Ricardo Ribeiro dos Santos Bruno Solano de Freitas Souza Milena Botelho Pereira Soares 《International journal of molecular sciences》2021,22(7)
Chagas disease, caused by the parasite Trypanosoma cruzi (T. cruzi), remains a serious public health problem for which there is no effective treatment in the chronic stage. Intense cardiac fibrosis and inflammation are hallmarks of chronic Chagas disease cardiomyopathy (CCC). Previously, we identified upregulation of circulating and cardiac miR-21, a pro-fibrotic microRNA (miRNA), in subjects with CCC. Here, we explored the potential role of miR-21 as a therapeutic target in a model of chronic Chagas disease. PCR array-based 88 microRNA screening was performed in heart samples obtained from C57Bl/6 mice chronically infected with T. cruzi and serum samples collected from CCC patients. MiR-21 was found upregulated in both human and mouse samples, which was corroborated by an in silico analysis of miRNA-mRNA target prediction. In vitro miR-21 functional assays (gain-and loss-of-function) were performed in cardiac fibroblasts, showing upregulation of miR-21 and collagen expression upon transforming growth factor beta 1 (TGFβ1) and T. cruzi stimulation, while miR-21 blockage reduced collagen expression. Finally, treatment of T. cruzi-infected mice with locked nucleic acid (LNA)-anti-miR-21 inhibitor promoted a significant reduction in cardiac fibrosis. Our data suggest that miR-21 is a mediator involved in the pathogenesis of cardiac fibrosis and indicates the pharmacological silencing of miR-21 as a potential therapeutic approach for CCC. 相似文献
58.
Ngambo Mikala Berthier Paul Ammari Nader Dyrda Katia Fernandez Jos M. 《International Journal of Information Security》2021,20(4):621-645
International Journal of Information Security - Cardiac implantable electronic devices (CIED) are vulnerable to radio frequency (RF) cyber-attacks. Besides, CIED communicate with medical equipment... 相似文献
59.
de Moraes Danielle Rodrigues Soares Laene Oliveira de Almeida Guimares Vanessa de Oliveira Katia Ferreira Hernndez-Callejo Luis Vieira Gisele Maria Ribeiro Boloy Ronney Arismel Mancebo 《Clean Technologies and Environmental Policy》2022,24(5):1389-1402
Clean Technologies and Environmental Policy - This paper examines the net environmental impact for the Fuel Cell Electric Vehicle, in special the Solid Oxide Fuel Cell Electric Vehicle (SOFCEV), by... 相似文献
60.
Makris Dimos Kaliakatsos-Papakostas Maximos Karydis Ioannis Kermanidis Katia Lida 《Neural computing & applications》2019,31(6):1793-1804
Neural Computing and Applications - Machine learning has shown a successful component of methods for automatic music composition. Considering music as a sequence of events with multiple complex... 相似文献