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51.
Starch and beta-glucan are most abundant carbohydrate polymers available in oat products; however, their simultaneous release during extraction depends on morphological and processing conditions of raw material. The study analyzes the mutual correlation between the sample (oat flakes and bran) and treatment types (microwave heating (MW)—1–5 min; conventional heating (CH)—7 min) on water extract properties focusing on beta-glucan, starch, and glucose content as well as the antioxidant activity of water extracts. The strong negative partial coefficient correlation was found between solids-starch (??0.65) and starch-glucose (??0.89) content as well as DPPH (??0.66) antioxidant activity in oat flakes revealing the high release of glucose to the water phase and its prooxidant activity. For the oat bran, positive and very high partial coefficient was found for both glucose (0.98) and beta-glucan (0.98) content in solids while the mutual interaction between them was highly negative (??0.97), meaning the more beta-glucan, the less glucose in the water phase. 相似文献
52.
This paper investigates the effectiveness and applicability of fusing three wireless positioning algorithms to determine the positions and track nomadic sensor nodes in real environment conditions. We fuse finger printing and atomic multilateration processes to give the system the best feasible region and to ensure that the later does not sway much due to accumulative errors. The extended Kalman filter is then used for refining the estimated position in near real time. The paper further assesses the response speed and the accuracy of estimating the position of the nomadic nodes with a prudent distribution of the processing load. 相似文献
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Cameron Novak Michael Keller Theresa Meza James McKinnies Erik Espinosa Kristie Calhoun 《Fire Technology》2018,54(4):921-941
In the past, some fire investigators have determined the cause of a fire to be electrical in nature based, in part, on the presence of an electrical cord or cable found beneath a furniture leg or a cable wedged tightly under a staple. While fires resulting from these events are possible, the mechanisms that lead to these failures are poorly understood. In this paper, the results of four research projects are presented. The first three projects focused on the creation of a pinched cord failure under various current loads and pressures. In the last project, a typical nonmetallic-sheathed cable was damaged and then installed with an overdriven staple over the damaged location. In all tests, the cords and cables were subjected to current loads varying between 100 and 250% of the rated ampacity. The failure rate of pinched cords was approximately 1%, but required the use of overloaded circuits and pre-existing damage or special orientation of the cord under test. A critical factor worth considering with these failures, which is often not accounted for, is time. These failures may take weeks, months, or years to occur under normal conditions, although some investigators may assume they develop nearly instantaneously. The conditions of the circuit are also important, as the only way a failure developed in these tests was by operating the circuits in excess of their rated parameters. 相似文献
57.
Since the 2007/08 food price crisis there has been a proliferation of multi-stakeholder processes (MSPs) devoted to bringing diverse perspectives together to inform and improve food security policy. While much of the literature highlights the positive contributions to be gained from an opening-up of traditionally state-led processes, there is a strong critique emerging to show that, in many instances, MSPs have de-politicizing effects. In this paper, we scrutinize MSPs in relation to de-politicization. We argue that re-building sustainable and just food systems requires alternative visions that can best be made visible through politicized policy processes. Focusing on three key conditions of politicization, we examine the UN Committee on World Food Security as a MSP where we see a process of politicization playing out through the endorsement of the ‘most-affected’ principle, which is in turn being actively contested by traditionally powerful actors. We conclude that there is a need to implement and reinforce mechanisms that deliberately politicize participation in MSPs, notably by clearly distinguishing between states and other stakeholders, as well as between categories of non-state actors. 相似文献
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Yingying Shi Lijun Luo Yefei Zhang Yu Chen Shan Wang Lingxin Li Yanju Long Fengzhi Jiang 《Journal of Materials Science》2018,53(2):1049-1064
The porous platelet-shaped α-Bi2O3 photocatalyst was successfully synthesized by a novel hydrothermal–calcination method assisted with ethylenediamine and polyvinylpyrrolidone. The physical and chemical properties of α-Bi2O3 photocatalyst were characterized based on XRD, XPS, SEM, TEM, EDS, UV–Vis DRS, and PL techniques. The influence of preparation conditions on the formation of α-Bi2O3 photocatalyst was investigated, and the effect of catalyst dosage and pH value on the EE2 removal rate was also investigated. The synthesized porous platelet-shaped α-Bi2O3 photocatalyst exhibited excellent photocatalytic activity for 17α-ethynylestradiol (EE2), and 97.8% of EE2 was removed after 75 min of visible light irradiation using α-Bi2O3 as photocatalyst. The reaction rate constant over the porous platelet-shaped α-Bi2O3 photocatalyst was 11.6 and 11.4 times of that of traditional α-Bi2O3 and N-TiO2, respectively. The possible photocatalytic mechanism has been discussed on the basis of the theoretical calculation and the experimental results. The porous platelet-shaped α-Bi2O3 was a stable and efficient photocatalyst, proving that it is a promising photocatalyst. 相似文献
59.
Erwin Krauskopf 《Scientometrics》2018,116(3):1805-1815
Researchers continually strive to communicate their findings to peers, hoping to receive recognition for their contribution in a not-so-distant future. The prevailing idea of “publish or perish” becomes imperative when researchers are applying for competitive grants or academic promotions. Choosing a suitable journal has become an important issue as thousands of journals are available. One of the aspects considered by researchers is the journal’s indexation status. Scopus continuously evaluates journals submitted by publishers for indexation, and later, to verify if quality is maintained. During this re-evaluation process, some publication concerns may be raised at journal or publisher level. Consequently, Scopus periodically issues a list of discontinued journals. However, not all journals update their websites in order to inform readers that they have been discontinued. This study shows that 56 journals that were discontinued in 2016 currently affirm on their websites that they are indexed by Scopus. In addition, another 20 journals discontinued in 2016, which do not specifically state that they are indexed by Scopus, include a widget from SCImago that may generate confusion about their current indexing situation. For some journals it seems that the emphasis is placed more on the publishing end of the business than the dissemination of research findings. This study shows that regular updates are among the responsibilities that editorial teams must maintain to ensure the quality and accuracy of the information posted on journal websites. 相似文献
60.
Pooyan Ayar Fernando Moreno-Navarro Miguel Sol-Sánchez Mª Carmen Rubio-Gámez 《Materials and Structures》2018,51(1):25
Recovery capability of bituminous materials plays a significant role in the development of new technologies for extending the service life of asphalt pavements. This capability originates from various phenomena such as thixotropy, cooling, relaxation of hardening, or healing. However, their real effect on mechanical response is not clear. This article aims to investigate how rest periods (RPs) available between traffic loads can contribute to the damage recovery of bituminous materials. For this purpose, different types and durations of RPs were applied during the laboratory evaluation of fatigue resistance of these materials using the University of Granada Fatigue Asphalt Cracking Test method. The results indicate that the addition of RPs to the loading regime could lead to an extension in the fatigue life of bituminous materials. Additionally, an increase in the RP duration showed a positive impact on the resistance of the materials against cyclic loading. Nonetheless, these benefits are not only related to the recovery of lost properties during RPs, but also a growth in the amount of plastic deformations as a result of the applying RPs could delay the appearance of damages (i.e. cracking). Consequently, the bituminous material can tolerate a higher number of load cycles during fatigue test. 相似文献