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排序方式: 共有1545条查询结果,搜索用时 10 毫秒
51.
Emna B. Saafi‐Ben Salah Guido Flamini Amira El Arem Manel Issaoui Samia Dabbou Leila BenYahia Ali Ferchichi Mohamed Hammami Lotfi Achour 《International Journal of Food Science & Technology》2012,47(9):1903-1908
This paper reports a discrimination study based on the physico‐chemical characteristics, fatty acids and profile of volatile compounds of the seeds from seven date palm varieties (Phoenix dactylifera L.) grown in Tunisia. Date seeds contained 10.49–14.76% moisture; 6.28–11.2% fat (on a dry weight basis); 2.67–12.85% protein; 0.91–6.06% reducing sugar; 0.61–2.98% sucrose and 0.97–1.17% ash. Gas liquid chromatography revealed that the oil fraction of the date palm seeds contained eighteen fatty acids, with oleic acid (30.77–42.50%) and lauric acid (18.51–27.48%) as the main unsaturated and saturated ones. Volatile profile showed differences among varieties. In total, forty‐five compounds were identified, mainly alcohols, aldehydes and unsaturated hydrocarbons ones. This study provides evidence that the seeds of date may be a potential source of valuable nutrients with interesting functionality. 相似文献
52.
Present assembly systems are often based on rigid, line-based approaches and are hindered in their reconfiguration capability. Line-less Mobile Assembly Systems (LMAS) are a novel approach for assembly organization. They improve flexibility through mobile resources, permitting spatiotemporal freedom in scheduling and resource assignment. This paper presents a method for a priori assessment of LMAS during the early stages of the assembly system design process. The method applies a modified, extended mean value analysis to a closed queuing network representation of LMAS to estimate performance. The method is validated model analysis and comparison on two use cases indicating plausible model behavior. 相似文献
53.
Transport and storage equipment for wood pellets can in theory be readily improved through simulation approaches like the discrete element method. However, scientific investigations verifying the applicability of the discrete element method in case of non-spherical particles are still limited. The sensitivity of simulations on the size and shape approximation of particles and mixing and segregation behavior are not well studied. These issues are addressed in the current paper. For a model type grate system experimental and numerical investigations of the mixing behavior of wood pellets under different motion patterns are performed. Results indicate that the discrete element method is well capable of representing experimentally obtained results. Altering the representation of the size distribution has impact on the segregation behavior, but does not strongly impact the overall mixing tendencies. 相似文献
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The crushing behaviour of sinter from blast furnace operations is known to depend on its temperature. In order to characterize it, hot sinter was subject to single particle tests in a very basic drop weight tester. Additionally, a laboratory jaw crusher was sacrificed to work the same feed material. As the results regarding net energy input were not consistent, two common rocks were tested in comparison with both the drop weight and the jaw crusher. Although some discrepancies remained, the results with the rocks can basically be considered as consistent. This investigation illustrates some of the difficulties that can arise when established test methods are applied on material with deviant properties. 相似文献
56.
Enhancing the temporal resolution of satellite-based flood extent generation using crowdsourced data for disaster monitoring 总被引:1,自引:0,他引:1
Remote-sensing satellite data are routinely used during disasters for damage assessment and to coordinate relief operations. Although there is a plethora of satellite sensors able to provide actionable data about an event, their temporal resolution is limited by their revisit time, presence of clouds, and errors in the reception of data. These limitations do not allow for an uninterrupted monitoring, which is crucial during disasters and emergencies. This research presents an approach that leverages the increased temporal resolution of crowdsourced data to partially overcome the limitations of satellite data. The proposed approach focuses on the geostatistical analysis of a combined satellite and Twitter data to help delineate the flood extent on a daily basis. The crowdsourced data are used to augment satellite imagery from Advanced Land Imager instrument on Earth Observating One (EO-1) satellite, Landsat 8, WorldView-2, and WorldView-3. The proposed methodology was applied to estimate the daily flood extents in Charleston, South Carolina, caused by the October 2015 North American storm complex. The results of the proposed methodology indicate that the user-generated data can be utilized adequately to both bridge the temporal gaps in the satellite-based observations and also increase the spatial resolution of the flood extents. 相似文献
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Guglielmo Barone Antonello d’Alessandro Guido de Blasio 《Papers in Regional Science》2019,98(5):1893-1902
National policies may have heterogeneous effects at the regional level. When coming to programmes aimed at increasing human capital, worker mobility from poorer to richer regions can reduce the benefits of the policy for the former areas. We focus on Italy and estimate the impact of education on the probability of migrating from a lagging area to a leading one. Endogeneity is addressed by exploiting an increase in the minimum school-leaving age in an instrumental variable framework. We find that one additional year of education increases the probability to migrate by 1.7 percentage points (9% of the average migration rate). 相似文献
59.
Cdric H. G. Neutel Jhana O. Hendrickx Wim Martinet Guido R. Y. De Meyer Pieter-Jan Guns 《International journal of molecular sciences》2020,21(23)
Background: Autophagy is a highly conserved catabolic homeostatic process, crucial for cell survival. It has been shown that autophagy can modulate different cardiovascular pathologies, including vascular calcification (VCN). Objective: To assess how modulation of autophagy, either through induction or inhibition, affects vascular and valvular calcification and to determine the therapeutic applicability of inducing autophagy. Data sources: A systematic review of English language articles using MEDLINE/PubMed, Web of Science (WoS) and the Cochrane library. The search terms included autophagy, autolysosome, mitophagy, endoplasmic reticulum (ER)-phagy, lysosomal, calcification and calcinosis. Study characteristics: Thirty-seven articles were selected based on pre-defined eligibility criteria. Thirty-three studies (89%) studied vascular smooth muscle cell (VSMC) calcification of which 27 (82%) studies investigated autophagy and six (18%) studies lysosomal function in VCN. Four studies (11%) studied aortic valve calcification (AVCN). Thirty-four studies were published in the time period 2015–2020 (92%). Conclusion: There is compelling evidence that both autophagy and lysosomal function are critical regulators of VCN, which opens new perspectives for treatment strategies. However, there are still challenges to overcome, such as the development of more selective pharmacological agents and standardization of methods to measure autophagic flux. 相似文献
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