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61.
Virgin olive oil (VOO) production in Tunisia: The commercial potential of the major olive varieties from the arid Tataouine zone 总被引:1,自引:0,他引:1
The commercial potential of olive oils from three consecutive crop years, derived from the main autochthonous olive varieties Chemlali Tataouine, Fakhari Douirat, Zarrazi Douirat and Dhokar Douirat grown in the arid region of Tataounine (Tunisia) was examined with regards to stability and nutrition aspects. Several characteristics such as fatty acid composition, the extremely high phenol-type antioxidant content, and the low levels of green pigments suggested that these oils, the only fat source for the local people, are of promising composition. Efforts to develop commercial products from these varieties could improve antioxidant intake of the local population. The introduction of Good Manufacturing Practices is a prerequisite so that the quality observed for oils obtained by an Abencor system to be achieved also in real life. This can be feasible through appropriate oleoculture, which is often the only viable agricultural activity in remote arid regions such as Tataouine. 相似文献
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Poly(3‐dodecylthiophene) (P3DDT) and poly(3‐decylthiophene) (P3DT) with high contents of head‐to‐tail linkages (86 and 85%, respectively) were synthesized in high yields by a facile oxidative polymerization with ferric chloride in chloroform at room temperature. We believe that the low concentration and ultraslow addition of monomers to ferric chloride contributed to the high regioregularity. Differential scanning calorimetry thermograms indicated that the formed polymers consisted of crystalline, quasiordered, and disordered phases, which is a common feature of highly regioregular polymers. We prepared conductive fabrics with specific resistance of 30 and 100 Ω/sq by impregnating polyamide fabrics in a chloroform solution of P3DDT and P3DT, respectively. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 2131–2135, 2004 相似文献
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Alexandre Campos Moraes Daniel Benevides da Costa Michel Daoud Yacoub 《Wireless Personal Communications》2012,64(1):3-19
Wireless communications systems in a frequency reuse environment are subject to cochannel interference. In order to improve the system performance, diversity techniques are deployed. Among the practical diversity schemes used, Equal-Gain Combining (EGC) appears as a reasonably simple and effective one. Unfortunately, the exact analysis of the outage probability of EGC receivers is rather intricate for it involves the evaluation of multifold nested integrals. It becomes mathematically intractable with the increase of the number of diversity branches and/or interferers. For example, for N B diversity branches and N I arbitrary independent cochannel interferers, the exact formulation using the convolutional approach requires 2 + N B + (N B × N I ) nested integrals, which, very quickly, and for any practical system, turns out to be mathematically intractable. In this paper, we propose accurate approximate formulations for this problem, whose results are practically indistinguishable from the exact solution. In our model, the system is composed by N B branches and N I interferers so that the desired signals are coherently summed, whereas the interfering signals are incoherently summed at the EGC receiver. Three sets of fading scenarios, namely α-μ , κ-μ, and η-μ, are investigated. The proposed approach is indeed flexible and accommodates a variety of mixed fading scenarios for desired and interfering signals. 相似文献
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Silicon - Based on the density functional theory (DFT), a systematic theoretical investigation on the structural parameters and finite temperature thermo-physical properties of cubic silicon... 相似文献
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Distributed storage systems are commonly used in modern computing. They are highly scalable and offer data replication and fault tolerance. The complexity of those systems makes them difficult to debug using traditional tools. The existing tools are able to evaluate the overall performance of such systems but they do not provide enough information to find the root cause of performance issues. In this article, we propose a tracing‐based performance analysis framework for storage clusters. We use a tracing strategy that reduces the tracing overhead in production systems. The traces collected from the different storage nodes are correlated and used to generate a data model that represents the cluster. Userspace tracing is used to gather data from the storage daemons, while Kernel tracing is used to provide detailed information about operating system internals such as disk queues, network queues and process scheduling. Efficient data structures are used to store the model and to generate metrics and graphical views. Our tool is used in different real world scenarios and is able to investigate interesting performance problems including I/O latencies, data replication and storage nodes failures. 相似文献
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Electronic commerce (E-commerce) is all the rage these days. About 100 million users and at least one million businesses already reachable via the Internet have made it that way. This critical mass compares to the market economy of North America, Japan or Europe. But doing business electronically means shifting critical business processes to open networks. It also means connecting back-end business applications in a secure and flexible way. Is there anything preventing the continued proliferation of this economy? Yes. A software infrastructure that allows all participants to carry out business transactions is still lacking. As a result, specialty market reference architectures are still needed to help identify important players, roles and relationships of the various markets and their participants. These architectures define the major components these participants require to carry out business transactions in that particular market. By defining interfaces and the semantics of the involved services, reference architectures provide patterns for software developers. These patterns help the software developers to implement coherent pacts to the overall electronic market system 相似文献