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1.
The 2008 European Microwave Week, which was held 27-31 October 2008 in Amsterdam, The Netherlands, hosted for the first time, a special event dedicated to women in engineering (WIE).  相似文献   
2.
This paper presents the first results of a study aimed at improving the seismic behavior of unreinforced masonry walls by a novel and sustainable application of basalt fibers. Five masonry panels were tested under out-of-plane actions, one of the common way of failure for masonry walls during an earthquake. Three of them were dry-strengthened by using two different techniques (a “lozenge” stitching and a “reticulum” one), while two unreinforced panels were used as reference. Besides, two other bigger masonry walls were dry-reinforced by “lozenge” stitching and vertical ropes and were tested by putting them horizontally and then loaded.

The results indicate the effectiveness of this dry retrofitting system, increasing the performance of masonry wall specimens under out-of-plane actions. Besides, this technique potentially appears fully sustainable, because it is cheap, compatible, reversible, fire, and chemical resistant, it improves but not replaces original materials and, finally, it does not substantially use synthetic adhesives. This last point is very important both for preserving the health of the applicators and in case of fire-load, where synthetic adhesive often fail.  相似文献   

3.
Phenol–formaldehyde resol resins were modified by the addition of silane (3‐aminopropyltriethoxysilane) and the lowering of pH (formic acid). The effects of the modifications on the properties of the resins during storage were studied through comparison with the parent resins and by viscosity measurements, NMR spectroscopy, ultraviolet–visible spectroscopy, and differential scanning calorimetry. Resin coatings on paper were prepared to determine the influence of discoloration of the resin solution on the color of the cured resin. A decrease in the pH of the NaOH‐catalyzed resin solutions lightened the color of the solutions and corresponding coatings, whereas silane additions made the coatings slightly more yellow. The lowering of pH increased the viscosities and decreased the reactivities of the resin solutions compared with the unmodified reference resins during storage. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1933–1941, 2007  相似文献   
4.
The synthesis of phenol–formaldehyde resol resins was carried out in two stages to facilitate the start of a conventional batch process. In the first stage, the starting material solution was preprocessed in a continuous‐flow stirred‐tank reactor with a 5‐min residence time. In the second stage, synthesis was continued in a batch reactor. Samples were analyzed by titrimetric methods, gas chromatography, nuclear magnetic resonance spectroscopy, and differential scanning calorimetry. Most of the starting materials were consumed in the preprocessing reactor, which allowed better control of the reactivity of the prepolymer solution in the second stage. The methylolation and condensation reactions proceeded steadily during the production process in the batch reactor. The results of the study indicated that dividing a conventional one‐stage batch process into two stages could facilitate the control of the initial stages of resol production. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103:371–379, 2007  相似文献   
5.
6.
A cooperative navigation procedure for a team of autonomous underwater vehicles (AUVs) is described and validated on experimental data. The procedure relies on acoustic communication networking among the AUVs and/or fixed acoustic nodes, and it is suitable as a low-cost solution for team navigation. Embedding the acoustic localization measurements in the communication scheme causes delays and sometimes loss of acoustic data, depending on acoustic propagation conditions. Despite this drawback, the results obtained show that on-board localization estimates have an error of the order of few meters, improving the overall navigation performance and leading the system towards long-term autonomy in terms of operating mission time, without the need of periodic resurfacings dedicated to reset the estimation error. The data were collected during the CommsNet ’13 experiment, led by the NATO Science and Technology Organization Center for Maritime Research and Experimentation (CMRE), and the Breaking The Surface ’14 workshop, organized by the University of Zagreb.  相似文献   
7.
This review summarizes reports of recurrent DNA sequence copy number amplifications in human neoplasms detected by comparative genomic hybridization. Some of the chromosomal areas with recurrent DNA copy number amplifications (amplicons) of 1p22-p31, 1p32-p36, 1q, 2p13-p16, 2p23-p25, 2q31-q33, 3q, 5p, 6p12-pter, 7p12-p13, 7q11.2, 7q21-q22, 8p11-p12, 8q, 11q13-q14, 12p, 12q13-q21, 13q14, 13q22-qter, 14q13-q21, 15q24-qter, 17p11.2-p12, 17q12-q21, 17q22-qter, 18q, 19p13.2-pter, 19cen-q13.3, 20p11.2-p12, 20q, Xp11.2-p21, and Xp11-q13 and genes therein are presented in more detail. The paper with more than 150 references and two tables can be accessed from our web site http://www.helsinki.fi/lglvwww/CMG.html. The data will be updated biannually until the year 2001.  相似文献   
8.
Local authorities need timely information on their greenhouse gas (GHG) emissions and their causes, comparison with other municipalities and tools for dissemination of information to the citizens. This paper presents a weekly GHG emission calculation system, CO2-report, which provides such data for citizens and local decision-makers in a timely manner, in contrast to the official emissions statistics, which are available on an annual basis 1–2 years afterwards. In this paper, we present the methodology and three main outputs of CO2-report: (1) weekly GHG emissions; (2) advance annual emissions; and (3) final annual emissions for 2009 with comparison of 64 municipalities in Finland. We explain the reasons for the large variability of annual emissions, from 5 to 13 t CO2-eq/capita, discuss the accuracy of advance and final emission estimates at local level, and show the weekly variability of emissions for three example municipalities with different emission profiles.  相似文献   
9.
Janne Monni  Leila Alvila 《Polymer》2008,49(18):3865-3874
The synthesis and curing of phenol-formaldehyde resol resins were monitored online by Raman spectroscopy. The synthesis of the resins (F/P 2.0, alkalinity 4.5 wt%) was studied at rising temperature (40-90 °C) for 90 min and at constant temperatures (80 °C, 90 °C, 100 °C, and 110 °C) for 120 min. The progress of the curing was investigated isothermally (80 °C, 90 °C, 100 °C, and 110 °C) for 120 min for three resins with different degrees of condensation. The synthesis and curing of the resins were started in the reactor and the advancement of the methylolation and condensation reactions was followed through the window of the reactor in the wave number region of 2000-400 cm−1 with use of a fiber optic probe for the data collection. The Raman spectra of six model compounds (formaldehyde, phenol, 2-hydroxybenzyl alcohol, 4-hydroxybenzyl alcohol, 2-benzylphenol, and 4-benzylphenol) were analyzed to facilitate the interpretation of the spectra of the resins. The consumptions of free phenol and free formaldehyde, as well as the progress of the methylolation and condensation reactions were easily monitored by following the changes in intensity of the characteristic Raman bands. The results for the cured resins obtained by Raman spectroscopy were in good agreement with the structures and residual reactivities studied by CP/MAS 13C NMR spectroscopy and differential scanning calorimetry (DSC), respectively. The results of the study show Raman spectroscopy to be a promising tool for the online monitoring and control of phenol-formaldehyde resol resin synthesis and curing; in addition, Raman spectroscopy offers an effective and fast method for structural study of the solid state resins.  相似文献   
10.
A modular technique originally proposed for waveguide junctions, the multimode equivalent network approach based on the integral equation formulation (IEMEN), is extended to the analysis of multilayer frequency selective surfaces integrated with waveguide array antennas. This technique represents each layer and transition between layers in terms of a generalized impedance or admittance matrix, obtained directly from the solution of an integral equation with reduced kernel. Thanks to the adopted formulation, the integral equation needs to be solved only in a limited set of frequency points. The IEMEN method is validated by comparison with results available in literature.  相似文献   
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