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The ternary system Bi–Fe–Sb has been investigated using differential thermal analysis (DTA), differential scanning calorimetry (DSC) and electron probe microanalysis (EPMA). Two isoplethic sections were studied: 80 at.% Bi and 30 at.% Sb. An isothermal section of the phase diagram was also studied at 523.15 K. Three invariant reactions were found: two ternary transitory peritectics and one ternary monotectic. No ternary compounds were found. In addition, a thermodynamic assessment was conducted. 相似文献
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Elane S Boa Morte Leticia M Costa Joaquim A Nobrega Maria das Gracas A Korn 《Food Additives & Contaminants》2008,25(5):616-621
The concentrations of major (Ca, K, Mg, Na and P) and trace elements (Al, Cu and Fe) in soy protein formulations sold in Bahia (Brazil) were determined by inductively coupled plasma-optical emission spectrometry (ICP-OES). Liquid and powdered soy protein formulation samples, both whole and light, were digested using a conventional heating program on a hot-plate. The powdered samples were prepared according to the label instructions for human consumption. A 5.0-ml aliquot of the soy protein emulsion was transferred to a borosilicate Erlenmeyer and concentrated nitric and sulfuric acid added. After a digestion time of approximately 50 min, hydrogen peroxide was added and heating continued to give a final volume of approximately 5 ml; the colorless digests were then made up to 15.0 ml with deionised water. Residual acid content was determined by acid-base titration. Good agreement between measured and certified values for all analytes in a non-fat milk powder (NIST SRM 1549) indicated that the method was suitable for major and trace elements determination in soy protein formulations. 相似文献
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Huili Li Yang Tian Nelson Menolli Jr Lei Ye Samantha C. Karunarathna Jesus Perez-Moreno Mohammad Mahmudur Rahman Md Harunur Rashid Pheng Phengsintham Leela Rizal Taiga Kasuya Young Woon Lim Arun Kumar Dutta Abdul Nasir Khalid Le Thanh Huyen Marilen Parungao Balolong Gautam Baruah Sumedha Madawala Naritsada Thongklang Kevin D. Hyde Paul M. Kirk Jianchu Xu Jun Sheng Eric Boa Peter E. Mortimer 《Comprehensive Reviews in Food Science and Food Safety》2021,20(2):1982-2014
Wild mushrooms are a vital source of income and nutrition for many poor communities and of value to recreational foragers. Literature relating to the edibility of mushroom species continues to expand, driven by an increasing demand for wild mushrooms, a wider interest in foraging, and the study of traditional foods. Although numerous case reports have been published on edible mushrooms, doubt and confusion persist regarding which species are safe and suitable to consume. Case reports often differ, and the evidence supporting the stated properties of mushrooms can be incomplete or ambiguous. The need for greater clarity on edible species is further underlined by increases in mushroom-related poisonings. We propose a system for categorizing mushroom species and assigning a final edibility status. Using this system, we reviewed 2,786 mushroom species from 99 countries, accessing 9,783 case reports, from over 1,100 sources. We identified 2,189 edible species, of which 2,006 can be consumed safely, and a further 183 species which required some form of pretreatment prior to safe consumption or were associated with allergic reactions by some. We identified 471 species of uncertain edibility because of missing or incomplete evidence of consumption, and 76 unconfirmed species because of unresolved, differing opinions on edibility and toxicity. This is the most comprehensive list of edible mushrooms available to date, demonstrating the huge number of mushrooms species consumed. Our review highlights the need for further information on uncertain and clash species, and the need to present evidence in a clear, unambiguous, and consistent manner. 相似文献
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泡沫作为一种新的无源干扰手段,对被动毫米波制导武器干扰作用明显。从散射、反射和吸收角度对泡沫干扰机理进行了阐述,对被动毫米波制导武器的探测原理进行了简要介绍。根据被动毫米波制导武器探测目标及泡沫干扰的要求,分别计算了被动毫米波制导武器的遮蔽面密度和泡沫两点间面密度,通过两种面密度的比较,对泡沫的干扰效能进行了分析。 相似文献
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Yonghyun Kim Huiwen Liu Yi Liu Boa Jin Hao Zhang Wenjing Tian Chan Im 《Frontiers of Chemical Science and Engineering》2021,15(1):187-197
Cesium lead halide perovskite(CsPbX3,X=Cl,Br,I)quantum dots(QDs)and their partly Mn2+-substituted QDs(CsPb1–xMnxX3)attract considerable attention owing to their unique photoluminescence(PL)efficiencies.The two types of QDs,having different PL decay dynamics,needed to be further investigated in a form of aggregates to understand their solid-state-induced exciton dynamics in conjunction with their behaviors upon degradation to achieve practical applications of those promising QDs.However,thus far,these QDs have not been sufficiently investigated to obtain deep insights related to the long-term stability of their PL properties as aggregated solid-states.Therefore,in this study,we comparatively examined CsPbX3-and CsPb1–xMnxX3-type QDs stocked for>50 d under dark ambient conditions by using excitation wavelength-dependent PL quantum yield and time-resolved PL spectroscopy.These investigations were performed with powder samples in addition to solutions to determine the influence of the inter-QD interaction of the aged QD aggregates on their radiative decays.It turns out that the Mn2+-substituted QDs exhibited long-lasting PL quantum efficiencies,while the unsubstituted CsPbX3-type QDs exhibited a drastic reduction of their PL efficiencies.And the obtained PL traces were clearly sensitive to the sample status.This is discussed with the possible interaction depending on the size and distance of the QD aggregates. 相似文献
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Elane S. Boa Morte Letícia M. Costa Joaquim A. Nóbrega 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2013,30(5):616-621
The concentrations of major (Ca, K, Mg, Na and P) and trace elements (Al, Cu and Fe) in soy protein formulations sold in Bahia (Brazil) were determined by inductively coupled plasma–optical emission spectrometry (ICP–OES). Liquid and powdered soy protein formulation samples, both whole and light, were digested using a conventional heating program on a hot-plate. The powdered samples were prepared according to the label instructions for human consumption. A 5.0-ml aliquot of the soy protein emulsion was transferred to a borosilicate Erlenmeyer and concentrated nitric and sulfuric acid added. After a digestion time of ~50 min, hydrogen peroxide was added and heating continued to give a final volume of ~5 ml; the colorless digests were then made up to 15.0 ml with deionised water. Residual acid content was determined by acid-base titration. Good agreement between measured and certified values for all analytes in a non-fat milk powder (NIST SRM 1549) indicated that the method was suitable for major and trace elements determination in soy protein formulations. 相似文献
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针对单电磁导向系统参数变化及外部扰动对悬浮气隙高度产生的影响,提出了RBF神经网络自适应滑模控制方法.采用RBF神经网络并利用其学习功能,对直线电梯单电磁悬装置不确定参数进行自适应补偿,取代了常规滑模控制切换部分,并且消除了系统高频抖振现象.通过比例微分并行控制提高了RBF神经网络参数的收敛性,改善了局部极小现象的发生,增强了系统的鲁棒性,并采用Lyapunov稳定性理论证明了系统的稳定性.Matlab仿真显示该方法具有良好的跟踪性和鲁棒性. 相似文献
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A growing number of companies have begun to realise the potential for differentiating their product offerings by integrating services to provide customised solutions. Although there is now an extensive and growing literature on this trend, researchers have only recently begun to consider the pricing structures for such solutions. To address this shortcoming, the present study adopts an exploratory case-based approach to investigate a buyer (drilling contractor) and two suppliers of offshore capital equipment, each of whom provides condition-based maintenance solutions for offshore drilling units in the upstream oil and gas industry. The findings of the study identify a number of underlying mechanisms for solution offerings (i.e. innovativeness, benchmarking alternatives, measurability, replicability and operational risk) that are important considerations in the process of determining appropriate pricing structures based on the buyer’s business model, procurement practices and maintenance strategy vis-à-vis the supplier’s capabilities and the buyer–supplier relationship. The present study contributes to the literature by providing empirical evidence on and insight into the complexity of determining the pricing structure for solution offerings from the perspective of the supplier as well as the buyer. 相似文献