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111.
Analog Integrated Circuits and Signal Processing - Nowadays, there has been an intensive increase in embedded systems complexity. So that optimization and performance development become an...  相似文献   
112.
Networks and Spatial Economics - This paper introduces a clear distinction between interregional and intraregional transportation cost in a mixed New Economic Geography and Urban Economics model...  相似文献   
113.
Allani  Sabri  Yeferny  Taoufik  Chbeir  Richard  Yahia  Sadok Ben 《World Wide Web》2020,23(4):2303-2322
World Wide Web - In the last decade, Vehicular Ad hoc NETworks (VANETs) have attracted researchers, automotive companies and public governments, as a new communication technology to improve the...  相似文献   
114.
Scientometrics - Although the overall analysis of the citations received by Nobel laureates in the scientific background of their Nobel Prize gives an overview of how and when Nobel-awarded...  相似文献   
115.
The Journal of Supercomputing - Cloud computing represents the latest technology that has revolutionized the world of business. It is a promising solution giving companies the possibility of...  相似文献   
116.
Five triterpene alcohols and four 4-monomethylsterols were identified by GC–MS during the ripening of Picholine olive. The quantitative characterisation of these compounds was performed using GC–FID. The results showed that the maximum level of total triterpene alcohols (263.68 mg/100 g oil) was reached at 26th week after the flowering date (WAF) of olive; whilst the highest level of total 4-monomethylsterols (234 mg/100 g oil) was attained at 24th WAF of fruit. The percentage of these two classes represented 20–33% of total phytosterols during olive maturity. 24-Methylene cycloartenol (12–207 mg/100 g oil) and cycloartenol (27–198 mg/100 g oil) were the predominant triterpene alcohols during the ripening of Picholine olive; whereas citrostadienol (30–161 mg/100 g oil) and cycloeucalenol (11–74 mg/100 g oil) were the main 4-monomethylsterol compounds followed by obtusifoliol and gramisterol. β-Amyrin, δ-amyrin and traroxerol were less present in Picholine olive and they accounted for 14% of total triterpene alcohols at complete maturity of fruit. The level of these methylsterols was overwhelmed by the amount of 4-desmethylsterols at each stage of Picholine olive maturity.  相似文献   
117.
BACKGROUND: Characterisation of the essential oils from O. glandulosum collected in three locations of Tunisia, chemical composition and the evaluation of their antioxidant activities were carried out. RESULTS: The essential oils from Origanum vulgare L. subsp. glandulosum (Desf.) Ietswaart collected from three localities of north Tunisia—Krib, Bargou and Nefza—were obtained in yields of 2.5, 3.0 and 4.6% (v/w), respectively. The essential oils were analysed by GC and GC/MS and assayed for their total phenolics content, by the Folin–Ciocalteu method, and antioxidant effectiveness, using the 2,2‐diphenyl‐1‐picrylhydrazil (DPPH) radical scavenging assay. The main components of these essential oils, from Nefza, Bargou and Krib, were p‐cymene (36%, 40% and 46%), thymol (32%, 39% and 18%), γ‐terpinene (24%, 12% and 16%) and carvacrol (2%, 2% and 15%), respectively). The ability to scavenge the DPPH radicals, expressed by IC50, ranged from 59 to 80 mg L?1. The total phenolic content, expressed in gallic acid equivalent (GAE) g kg?1 dry weight, varied from 9.37 to 17.70 g kg?1 dw. CONCLUSIONS: A correlation was identified between the total phenolic content of the essential oils and DPPH radical scavenger capacity. The occurrence of a p‐cymene chemotype of O. glandulosum in the northern region of Tunisia is demonstrated. Copyright © 2010 Society of Chemical Industry  相似文献   
118.
Supported gold nanoparticles were prepared on clay minerals from the smectite and sepiolite–palygorskite groups (particularly montmorillonite and sepiolite) by cation adsorption from the cationic gold precursor Au(en)2Cl3 (en = ethylenediamine). Thermal gravimetric analysis, X-ray diffraction, transmission electron microscopy (TEM), high resolution TEM (HRTEM) and energy dispersive X-ray spectroscopy (EDS) were used to characterize these potential gold catalysts. The results show that the mean diameters of gold particles supported both on sepiolite and on montmorillonite are below 5 nm after calcination at 350–450 °C when the gold loading is lower than 2 wt.%. An increase of the amount of the gold precursor results in agglomeration of gold nanoparticles. An organosilane functionalized sepiolite was also used as support to obtain highly dispersed gold nanoparticles on the modified mineral surfaces, with narrow size distribution and an average size of 2.7 nm.  相似文献   
119.
In this paper, the problem of equalization of linear multi‐input multi‐output (MIMO) channels is addressed. Using an algebraic approach, we propose a unifying formalism for the linear time‐invariant/time‐varying channel equalization problem. A new definition called algebraic equalization is presented. This allows us to derive the necessary and sufficient condition on the existence of equalizer. We describe the received signals in terms of Kalman model. This then provides us with a test of channel equalization, which may be performed formally in terms of ranks of some related matrices. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
120.
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