全文获取类型
收费全文 | 170篇 |
免费 | 1篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 9篇 |
化学工业 | 17篇 |
金属工艺 | 2篇 |
建筑科学 | 3篇 |
能源动力 | 3篇 |
轻工业 | 9篇 |
水利工程 | 3篇 |
无线电 | 23篇 |
一般工业技术 | 29篇 |
冶金工业 | 36篇 |
原子能技术 | 2篇 |
自动化技术 | 36篇 |
出版年
2023年 | 1篇 |
2022年 | 5篇 |
2021年 | 7篇 |
2019年 | 2篇 |
2017年 | 1篇 |
2016年 | 3篇 |
2015年 | 3篇 |
2014年 | 11篇 |
2013年 | 16篇 |
2012年 | 4篇 |
2011年 | 7篇 |
2010年 | 3篇 |
2009年 | 8篇 |
2008年 | 8篇 |
2007年 | 11篇 |
2006年 | 12篇 |
2005年 | 4篇 |
2004年 | 3篇 |
2003年 | 1篇 |
2002年 | 2篇 |
2001年 | 1篇 |
2000年 | 5篇 |
1999年 | 7篇 |
1998年 | 9篇 |
1997年 | 7篇 |
1996年 | 5篇 |
1995年 | 5篇 |
1994年 | 2篇 |
1993年 | 2篇 |
1992年 | 2篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 3篇 |
1977年 | 1篇 |
1976年 | 2篇 |
1967年 | 1篇 |
1955年 | 1篇 |
排序方式: 共有172条查询结果,搜索用时 31 毫秒
51.
Maria Teresa Montagna Christian Napoli Osvalda De Giglio Roberta Iatta Giovanna Barbuti 《International journal of molecular sciences》2008,9(12):2614-2621
A screening survey of the presence of aflatoxin M1 (AFM1) was carried out on 265 samples of cheese made from cow, buffalo, goat, sheep, sheep-goat milk collected in the Apulia region (Southern Italy). Selected samples included unripened, medium and long-term ripened cheeses. AFM1 was found in 16.6% of the analyzed samples. The highest positive incidence was for medium and long-term ripened cheeses, especially those made from sheep-goat milk, while buffalo cheeses tested consistently negative. Our results show that the level of contamination by AFM1 in dairy products from Apulia Region are lower than in other Italian and European regions. Moreover, it is important to underline that a common European norm concerning the AFM1 threshold limits for dairy products is still lacking. 相似文献
52.
Rosanna Migliore Matteo Scala Anna Napoli Antonino Messina 《Journal of Engineering Mathematics》2013,82(1):187-197
A microscopic master equation describing the dynamics of two qubits coupled via a nonlinear mediator is constructed supposing that the two qubits, as well as the nonlinear mode, interact, each with its own independent bosonic bath. Generally speaking the master equation derived in this way represents a more appropriate tool for studying the dynamics of open quantum systems. Indeed we show that it is more complex than the phenomenological master equation, constructed simply adding ad hoc dissipative terms. 相似文献
53.
54.
Sarah L. Nolin Eleonora Napoli Amanda Flores Randi J. Hagerman Cecilia Giulivi 《International journal of molecular sciences》2021,22(11)
Fifty-five to two hundred CGG repeats (called a premutation, or PM) in the 5′-UTR of the FMR1 gene are generally unstable, often expanding to a full mutation (>200) in one generation through maternal inheritance, leading to fragile X syndrome, a condition associated with autism and other intellectual disabilities. To uncover the early mechanisms of pathogenesis, we performed metabolomics and proteomics on amniotic fluids from PM carriers, pregnant with male fetuses, who had undergone amniocentesis for fragile X prenatal diagnosis. The prenatal metabolic footprint identified mitochondrial deficits, which were further validated by using internal and external cohorts. Deficits in the anaplerosis of the Krebs cycle were noted at the level of serine biosynthesis, which was confirmed by rescuing the mitochondrial dysfunction in the carriers’ umbilical cord fibroblasts using alpha-ketoglutarate precursors. Maternal administration of serine and its precursors has the potential to decrease the risk of developing energy shortages associated with mitochondrial dysfunction and linked comorbidities. 相似文献
55.
In the present paper we propose an extension of the direct-forcing immersed boundary technique, recently developed and employed by Verzicco and co-authors [Fadlun EA, Verzicco R, Orlandi P, Mohd-Yusof J. Combined immersed-boundary finite-difference methods for three-dimensional complex flow simulations. J Comput Phys 2000;161:35–60; Verzicco R, Fatica M, Iaccarino G, Moin P, Khalighi B. Large eddy simulation of a road vehicle with drag-reduction devices. AIAA J 2002;40(12):2447–55; Cristallo A, Verzicco R. Combined immersed boundary/large-eddy-simulations of incompressible three-dimensional complex flows. Flow Turbul Combust 2006;77(1–4):3–26.] and successively improved by Balaras and co-authors [Gilmanov A, Sotiropoulos F, Balaras E. A general reconstruction algorithm for simulating flows with complex 3D immersed boundaries on Cartesian grids. J Comput Phys 2003;191:660–9; Balaras E. Modeling complex boundaries using an external force field on fixed Cartesian grids in large-eddy simulations. Comput Fluids 2004;33:375–404]. We extend the aforementioned technique to curvilinear-coordinate, structured grid, Navier–Stokes solvers. This improved technique allows for more flexibility and efficiency when compared to standard methods in which the technique is coupled with orthogonal-grid solvers. Additional modifications are also proposed with respect to the state-of-art, which allow to deal with general shaped, multiple-body immersed surfaces and to make the interpolation of the velocity field off the body suitable for curvilinear grids. Several tests have been carried out to check the reliability of the proposed technique: first we have considered the three-dimensional Stokes flow around a sphere, and compared the numerical results with the analytical ones. Second we have considered the two-dimensional unsteady flow around a circular cylinder placed between two parallel solid walls and compared the results with those of the database of the Priority Research Program ‘Flow Simulation on High Performance Computers’ of the German Research Association (DFG). Third, we have considered the two-dimensional flow within a S-shaped duct containing an elliptical valve. Finally, we have applied the technique to the study of a practical high-Reynolds number industrial problem.The geometrical configuration of the first two test cases is suited for both Cartesian and curvilinear algorithms. The geometry of the third test case is suited for curvilinear meshes and makes the use of Cartesian grids very inefficient and less accurate than the curvilinear ones. In these cases Cartesian – as well as curvilinear – mesh simulations have been carried out. Finally, the geometry of the high-Reynolds industrial problem is suited for curvilinear grids.The proposed technique has shown to preserve at least the same level of accuracy of its Cartesian counterpart allowing to reduce in a considerable way the computational cost of the simulations. When the geometry is better suited for curvilinear meshes, the reduction of the computational cost is accompanied by an increased accuracy with respect to the Cartesian counterpart.We also propose a simplified direct-forcing, semi-implicit method, allowing reduced computational cost with respect to the literature techniques. We have checked the accuracy of the technique and shown that when the Reynolds number is large enough, the present simplified technique allows the use of time steps much larger than those allowed by the explicit time-advancement scheme, preserving the accuracy of the results. 相似文献
56.
Lisa Cangioli Marco Mancini Marco Napoli Camilla Fagorzi Simone Orlandini Francesca Vaccaro Alessio Mengoni 《International journal of molecular sciences》2022,23(7)
The taxonomic assemblage and functions of the plant bacterial community are strongly influenced by soil and host plant genotype. Crop breeding, especially after the massive use of nitrogen fertilizers which led to varieties responding better to nitrogen fertilization, has implicitly modified the ability of the plant root to recruit an effective bacterial community. Among the priorities for harnessing the plant bacterial community, plant genotype-by-microbiome interactions are stirring attention. Here, we analyzed the effect of plant variety and fertilization on the rhizosphere bacterial community. In particular, we clarified the presence in the bacterial community of a varietal effect of N and P fertilization treatment. 16S rRNA gene amplicon sequence analysis of rhizospheric soil, collected from four wheat varieties grown under four N-P fertilization regimes, and quantification of functional bacterial genes involved in the nitrogen cycle (nifH; amoA; nirK and nosZ) were performed. Results showed that variety played the most important role and that treatments did not affect either bacterial community diversity or bacterial phyla abundance. Variety-specific response of rhizosphere bacterial community was detected, both in relation to taxa (Nitrospira) and metabolic functions. In particular, the changes related to amino acid and aerobic metabolism and abundance of genes involved in the nitrogen cycle (amoA and nosZ), suggested that plant variety may lead to functional changes in the cycling of the plant-assimilable nitrogen. 相似文献
57.
Salvatore La Torre Margherita Napoli Mimmo Parente 《Formal Methods in System Design》2007,31(3):265-279
Visibly pushdown languages are an interesting subclass of deterministic context-free languages that can model nonregular properties
of interest in program analysis. Such class properly contains typical classes of parenthesized languages such as “parenthesis”,
“bracketed”, “balanced” and “input-driven” languages. It is closed under boolean operations and has decidable decision problems
such as emptiness, inclusion and universality. We study the membership problem for visibly pushdown languages, and show that
it can be solved in time linear in both the size of the input grammar and the length of the input word. The algorithm relies
on a reduction to the reachability problem for game graphs. We also discuss the time complexity of the membership problem
for the class of balanced languages which is the largest among those cited above. Besides the intrinsic theoretical interest,
we further motivate our main result showing an application to the validation of XML documents against Schema and Document
Type Definitions (DTDs).
Work partially supported by funds for the research from MIUR 2006, grant “Metodi Formali per la verifica di sistemi chiusi
ed aperti”, Università di Salerno.
A preliminary version of this paper was published in the Proceedings of the 4th International Symposium Automated Technology
for Verification and Analysis (ATVA 2006), Lecture Notes in Computer Science 4218, pp. 96–109, 2006. 相似文献
58.
R. Schwengner H. Schnare S. Frauendorf F. D?nau L. K?ubler H. Prade E. Grosse A. Jungclaus K. P. Lieb C. Lingk S. Skoda J. Eberth G. de Angelis A. Gadea E. Farnea D. R. Napoli C. A. Ur G. Lo Bianco 《Journal of research of the National Institute of Standards and Technology》2000,105(1):133-136
We have studied the isotopes 82Rb45, 83Rb46, and 84Rb47 to search for magnetic rotation which is predicted in the tilted-axis cranking model for a certain mass region around A = 80. Excited states in these nuclei were populated via the reaction 11B + 76Ge with E = 50 MeV at the XTU tandem accelerator of the LNL Legnaro. Based on a γ-coincidence experiment using the spectrometer GASP we have found magnetic dipole bands in each studied nuclide. The regular M1 bands observed in the odd-odd nuclei 82Rb and 84Rb include B(M1)/B(E2) ratios decreasing smoothly with increasing spin in a range of 13− ≤ Jπ ≤ 16−. These bands are interpreted in the tilted-axis cranking model on the basis of four-quasiparticle configurations of the type
. This is the first evidence of magnetic rotation in the A ≈ 80 region. In contrast, the M1 sequences in the odd-even nucleus 83Rb are not regular, and the B(M1)/B(E2) ratios show a pronounced staggering. 相似文献
59.
This paper analyzes the magnetic field analysis generated in a slot-bar, also taking into account the eddy currents, using the finite-elements method and the state-variables approach. After indicating the formulation of the procedure, the Authors mention the resulting possibility of building the equivalent network of the slot-bar, by through the determining the transfer function of the system. 相似文献
60.