全文获取类型
收费全文 | 298篇 |
免费 | 18篇 |
专业分类
电工技术 | 7篇 |
化学工业 | 94篇 |
金属工艺 | 2篇 |
机械仪表 | 7篇 |
建筑科学 | 13篇 |
能源动力 | 8篇 |
轻工业 | 23篇 |
水利工程 | 1篇 |
无线电 | 22篇 |
一般工业技术 | 60篇 |
冶金工业 | 19篇 |
原子能技术 | 2篇 |
自动化技术 | 58篇 |
出版年
2023年 | 8篇 |
2022年 | 19篇 |
2021年 | 24篇 |
2020年 | 5篇 |
2019年 | 14篇 |
2018年 | 13篇 |
2017年 | 4篇 |
2016年 | 10篇 |
2015年 | 8篇 |
2014年 | 10篇 |
2013年 | 19篇 |
2012年 | 15篇 |
2011年 | 20篇 |
2010年 | 15篇 |
2009年 | 15篇 |
2008年 | 14篇 |
2007年 | 12篇 |
2006年 | 6篇 |
2005年 | 5篇 |
2004年 | 3篇 |
2003年 | 2篇 |
2002年 | 6篇 |
2001年 | 6篇 |
2000年 | 3篇 |
1999年 | 8篇 |
1998年 | 7篇 |
1997年 | 5篇 |
1996年 | 6篇 |
1995年 | 3篇 |
1994年 | 2篇 |
1993年 | 5篇 |
1992年 | 3篇 |
1991年 | 6篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1988年 | 3篇 |
1986年 | 1篇 |
1985年 | 4篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1970年 | 1篇 |
排序方式: 共有316条查询结果,搜索用时 15 毫秒
31.
Maurizio Aceto Ornella Abollino Maria Concetta Bruzzoniti Edoardo Mentasti Corrado Sarzanini Mery Malandrino 《Food Additives & Contaminants》2002,19(2):126-133
Metals in wine occur at the mg l 1 level or less and, though not directly related to the taste of the final product, their content should be determined because excess is undesirable, and in some cases prohibited, due to potential toxicity. Lead content in wine, for example, is restricted in several states by legislation to guarantee consumer health protection. Of several methods for metal determination, techniques of atomic spectroscopy are the most sensitive and rapid. Most of the elements present in wine can be determined with these techniques, at concentrations ranging from the mg l -1 to the μg l -1 level. Here, inductively coupled plasma-atomic emission spectrometry (ICP-AES), flame atomic absorption spectrometry (flame-AAS) and graphite furnace-atomic absorption spectrometry (GF-AAS) are compared for their characteristics as employed in metal determination in wine. 相似文献
32.
Valentina Serra Edoardo Fiorillo Francesco Cucca Valeria Orr 《International journal of molecular sciences》2023,24(1)
The use of cryopreserved peripheral blood mononuclear cells is common in biological research. It is widely accepted that primary cells are rendered unusable by several freezing cycles, although this practice might be very helpful when the biological material is valuable and its re-collection is impractical. To determine the extent to which primary cells undergoing repeated freezing cycles are comparable to one another and to fresh samples, we evaluated overall lymphocyte viability, their proliferation and cytokine production capabilities, as well as the levels of 27 cell subtypes in ten human peripheral blood mononuclear cells frozen for five years and repeatedly thawed. As expected, we observed a progressive increase in cell death percentages on three rounds of thawing, but the frequency of the main lymphocyte subsets was stable across the three thawings. Nevertheless, we observed a significant reduction of B cell frequency in frozen samples compared to fresh ones. On repeated thawings and subsequent conventional stimulation, lymphocyte proliferation significantly decreased, and IL-10, IL-6, GM-CSF, IFN-gamma, and IL-8 showed a trend to lower values. 相似文献
33.
Lorenzo Moretti Davide Bizzoca Alessandro Geronimo Francesco Luca Moretti Edoardo Monaco Giuseppe Solarino Biagio Moretti 《International journal of molecular sciences》2022,23(17)
Osteoarthritis (OA) is a joint degenerative disease that most affects old age. The study of proteomics in synovial fluid (SF) has the task of providing additional elements to diagnose and predict the progress of OA. This review aims to identify the most significant biomarkers in the study of OA and to stimulate their routine use. Some of the major components of the ECM, such as proteoglycan aggrecan and decorin, were found considerably reduced in OA. Some biomarkers have proved useful for staging the temporality of OA: Periostin was found to be increased in early OA, while CRTA1 and MMPs were found to be increased in late OA. In its natural attempt at tissue regeneration, Collagen III was found to be increased in early OA while decreased in late OA. Some molecules studied in other areas, such as ZHX3 (oncological marker), LYVE1, and VEGF (lymph and angiogenesis markers), also have been found to be altered in OA. It also has been recorded that alteration of the hormonal pathway, using a dosage of PPAR-γ and RETN, can influence the evolution of OA. IL-1, one of the most investigated biomarkers in OA-SF, is not as reliable as a target of OA in recent studies. The study of biomarkers in SF appears to be, in combination with the clinical and radiological aspects, an additional weapon to address the diagnosis and staging of OA. Therefore, it can guide us more appropriately towards the indication of arthroplasty in patients with OA. 相似文献
34.
35.
Ermanno Barni Piero Savarino Gaetano di Modica Rosarina Carpignano Sisto Sergio Papa Giacomo Giraudo 《Dyes and Pigments》1984,5(1):15-36
Data on a series of 65 azo dyes derived from 4-alkylamido-2-hydroxybenzoic acids are reported. The dyes are suitable for application to polyamide fibres.Many correlations between the nature of substituents and the physical, spectroscopic or tinctorial properties of dyes were established. Correlations between structure and colour of dyed fabrics were also found. 相似文献
36.
A conforming plate bending solution using simple polynomial deflection functions of third-degree inside each triangular element is presented. In order to avoid normal slope discontinuities along the sides of the elements, the plate displacement parameters are subjected to ‘slope continuity conditions’ acting as constraints to the minimum potential energy problem. This is then solved by the classical method of Lagrange introducing multipliers as new auxiliary variables. If a special variational formulation of the problem is used, it can be shown that the Lagrangean multipliers are generalized stress parameters. The suggested solution is therefore basically a ‘mixed’ solution, the unknown variables of the problem being both displacement and stress parameters. Several numerical results are presented. 相似文献
37.
P. Savarino E. Barni G. Viscardi R. Carpignano G Di Modica 《Coloration Technology》1988,104(3):125-130
The dyeing equilibria of a set of monoazo dyes derived from 4-alkylamidosalicylic acids on nylon 6.6 have been studied. A Nemst distribution has been obtained indicating the prevailing mechanism of solution of the dye in the fibre Equilibrium depends on the length of the alkyl chain of the dye and on the concentration of dispersant. The latter affects the equilibrium differently according to the hydrophobicity of the dye. Linear relationships between the chain length and ΔHd? and ΔSd? have been found. 相似文献
38.
Edoardo Guerrini Pierangela Cristiani Stefano Pierpaolo Marcello Trasatti 《International Journal of Hydrogen Energy》2013
One-compartment (membraneless) microbial fuel cells (MFCs) are effective tools to test new bio-technology at a laboratory level. More efforts in MFC design and materials are necessary to move from laboratory tests to real applications. 相似文献
39.
Anna Osello Andrea Acquaviva Chiara Aghemo Laura Blaso Daniele Dalmasso David Erba Giovanni Fracastoro Damien Gondre Marco Jahn Enrico Macii Edoardo Patti Anna Pellegrino Paolo Piumatti Ferry Pramudianto Jerôme Savoyat Maurizio Spirito Riccardo Tomasi Joseph Virgone 《Energy Efficiency》2013,6(4):707-723
In this paper, we report a methodology, developed in the context of Smart Energy Efficient Middleware for Public Spaces European Project, aimed at exploiting ICT monitoring and control services to reduce energy usage and CO2 footprint in existing buildings. The approach does not require significant construction work as it is based on commercial-off-the-shelf devices and, where present, it exploits and integrates existing building management systems with new sensors and actuator networks. To make this possible, the proposed approach leverages upon the following main contributions: (a) to develop an integrated building automation and control system, (b) to implement a middleware for the energy-efficient buildings domain, (c) to provide a multi-dimensional building information modelling-based visualisation, and (d) to raise people’s awareness about energy efficiency. The research approach adopted in the project started with the selection, as case studies, of representative test and reference rooms in modern and historical buildings chosen for having different requirements and constraints in term of sensing and control technologies. Then, according to the features of the selected rooms, the strategies to reduce the energy consumptions were defined, taking into account the potential savings related to lighting, heating, ventilation, and air conditioning (HVAC) systems and other device loads (PC, printers, etc.). The strategies include both the control of building services and devices and the monitoring of environmental conditions and energy consumption. In the paper, the energy savings estimated through simulation, for both HVAC and lighting, are presented to highlight the potential of the designed system. After the implementation of the system in the demonstrator, results will be compared with the monitored data. 相似文献
40.
Edoardo Capuano Teresa Oliviero Martinus A.J.S van Boekel 《Critical reviews in food science and nutrition》2018,58(16):2814-2828
ABSTRACTThe same chemical reaction may be different in terms of its position of the equilibrium (i.e., thermodynamics) and its kinetics when studied in different foods. The diversity in the chemical composition of food and in its structural organization at macro-, meso-, and microscopic levels, that is, the food matrix, is responsible for this difference. In this viewpoint paper, the multiple, and interconnected ways the food matrix can affect chemical reactivity are summarized. Moreover, mechanistic and empirical approaches to explain and predict the effect of food matrix on chemical reactivity are described. Mechanistic models aim to quantify the effect of food matrix based on a detailed understanding of the chemical and physical phenomena occurring in food. Their applicability is limited at the moment to very simple food systems. Empirical modeling based on machine learning combined with data-mining techniques may represent an alternative, useful option to predict the effect of the food matrix on chemical reactivity and to identify chemical and physical properties to be further tested. In such a way the mechanistic understanding of the effect of the food matrix on chemical reactions can be improved. 相似文献