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31.
杨宇迪  程湛  满媛  李景明 《食品科学》2017,38(20):103-111
将葡萄籽超微粉碎并添到曲奇饼干中,探究其对曲奇饼干香气成分及感官品质的影响。采用气相色谱-质谱联用仪分别检测了普通葡萄籽粉、葡萄籽超微粉及添加超微粉前后曲奇饼干的香气成分,并结合偏最小二乘判别分析法研究葡萄籽超微粉对曲奇饼干香气成分的影响。结果显示,超微粉碎后香气物质的种类虽未发生明显的改变,但香气成分的相对含量显著增加。葡萄籽超微粉添加比例为5%时,烘烤香比较浓郁。当添加比例达到10%时,曲奇饼干整体风味较为复杂,包括苦杏仁味、香蕉味、水果味/青草味、面包味以及坚果味。采用9点享乐法感官品评结果可以看出,葡萄籽的添加可以为饼干带来可感知的变化,添加比例为5%时,香气得分最高。葡萄籽超微粉会给曲奇饼干香气带来积极的影响,添加比例在10%以内均可被消费者接受。  相似文献   
32.
The development of microbial fuel cells (MFCs) into a new type of carbon-neutral wastewater treatment technology requires efficient and low-cost oxygen reduction reaction catalysts in air cathodes. The use of raw soybean powder was investigated for synthesizing Fe–N–C ORR catalysts in a sacrificial SiO2 support method. ZnCl2 etching in the synthesis was found to facilitate the formation of hierarchical porous structures of Fe–N–C catalysts. Fe–N–C(1-1) catalyst synthesized with an optimal soybean/ZnCl2 mass ratio of 1:1 exhibited the highest ORR activity in air cathodes. The use of the obtained Fe–N–C(1-1) catalyst enables a maximum power production of ~0.480 mW cm−2 in MFCs, higher than commercial Pt/C (0.438 mW cm−2) with the same catalyst loading of 2 mg cm−2. Long-term MFC operations demonstrated that the Fe–N–C synthesized from raw soybean have high stability and toxic tolerance, indicating that abundant low cost soybean biomass is a potential material for ORR catalyst development in MFC applications.  相似文献   
33.
Soybean oil gums and soapstocks are important by-products that may potentially be contaminated by persistent organic pollutants (POP) such as polycyclic aromatic hydrocarbons (PAH) and phthalic acid esters (PAE), thus lowering the value when using them as starting materials to produce animal feed additives, food industry ingredients, and pharmaceutical products. In the present work, PAH and PAE distributions in these two types of by-products were detected using solvent extraction–solid phase extraction purification coupled with gas chromatography–mass spectrometry. Total PAH and PAE amounts in the soapstocks were significantly higher than those in the gums, thus indicating that neutralization showed much higher removal efficiency than degumming in terms of PAH and PAE eliminations. Meanwhile, the results proved that the concentrations of these two kinds of contaminants in the soybean oil gums and soapstocks were much higher than those in the soybean oils, suggesting that further investigations were needed and that the contents of PAH and PAE in soybean oil refining by-products should be carefully monitored and regulated.  相似文献   
34.
在单因素试验基础上采用响应面分析法优化非洲山毛豆种子凝集素的提取工艺。研究表明:TBS缓冲液为非洲山毛豆种子凝集素的最佳提取溶液;非洲山毛豆种子凝集素提取的优化工艺条件为料液比1:40(g/mL),pH8.0,Nacl浓度0.125mol/L,提取时间16h。  相似文献   
35.
The purpose of the current study is to identify the potential of energy-efficient hydrogen (H2) production from date seeds as biomass via steam gasification process along with heat integration in Gulf countries. A reaction kinetics model has been established for steam gasification with in-situ carbon dioxide (CO2) capture of date seeds using MATLAB software. The kinetics of reactions involved in the gasification process was calculated using the optimization parameters fitting approach. The heat integration model has been developed via mixed integer nonlinear programming (MINLP) in MATLAB. In the parametric study, temperature and steam/biomass ratio considered their impact on syngas composition and energy recovery. Results showed that both variables have a strong positive effect on H2 production and depicted maximum production of 68 mol% at a temperature of 750 °C with steam/biomass ratio of 1.2. Methane (CH4) and CO2 production were low in the product gas, which showed the activity of water gas shift reaction, methanation reaction, and carbonation reaction. Utilization of waste heat via process heat integration within the system reduced system's external heat load. More than 70% of energy recovered, which could be utilized for gasification and steam production. Energy analysis and process heat integration proved a prospective approach for energy-efficient and sustainable hydrogen production from date seeds.  相似文献   
36.
37.
基于多尺度的贝叶斯模型显著性检测   总被引:1,自引:0,他引:1       下载免费PDF全文
针对传统基于贝叶斯模型的显著性检测算法存在准确率不理想的问题,提出了一种基于多尺度的贝叶斯模型显著性检测算法。通过超像素分割算法(SLIC)将原图分割成不同尺度的超像素,根据超像素边界信息得到背景种子,进而通过距离计算和多尺度融合得到背景先验;对原图进行颜色增强,采用Harris算子对增强图进行检测角点求得凸包,融合不同尺度下的超像素得到凸包先验;融合背景先验和凸包先验得到最终先验;利用颜色直方图和凸包计算似然概率;将最终先验和似然概率通过贝叶斯模型计算显著图。在公开数据集MSRA1000、ECSSD上与多种传统算法进行准确率和召回率对比,该算法有更好的表现。  相似文献   
38.
The objectives of this study were to determine the optimal extraction conditions of polyphenols from Syzygium cumini seeds by response surface methodology and investigate their antioxidant activity and inhibition on α-amylase and pancreatic lipase. As results, the optimal extraction conditions in the ultrasonic extraction process which maximised total polyphenols content, minimised the IC50 values of α-amylase and pancreatic lipase were determined as follows: extraction time 60 min, ethanol concentration 63% and solvent/solid ratio 44 mL g−1. The main phenolic compounds in partially purified fraction of Syzygium cumini seeds were catechin, epicatechin, kaempferol, gallic, 5-caffeoylquinic, caffeic and ferulic acids. In addition, the partially purified fraction inhibited 87.66 ± 5.55 and 86.61 ± 3.15% of α-amylase and pancreatic lipase, respectively. The results suggested that Syzygium cumini seeds could be explored as a natural antioxidant and could be used as a source of highly antidiabetic and anti-obesity bioactive compounds.  相似文献   
39.
The present study examined the percentage oil output, energy and mechanical properties of selected bulk oilseeds namely pumpkin, hemp, sesame, milk thistle, cumin and flax by a uniaxial compression process of a maximum load capacity of 500 kN and a preset speed of 5 mm/min. Each sample was measured at 60 mm pressing height with a plunger using the pressing vessel of diameter 60 mm. The results show that milk thistle seeds required the highest force corresponding to the highest stress and energy demand for recovering the oil in both the bulk oilseeds and seedcakes. However, pumpkin seeds produced the maximum residual oil yield of 24.99 ± 0.04%, followed by sesame seeds at 21.29 ± 1.82% and then flax seeds at 22.61 ± 0.31%. The study revealed that higher energy is required to produce the maximum oil yield with minimum residual oil in the seedcake by continuous pressing.  相似文献   
40.
文章报道了一种以不同数量种晶介导合成CeO2多晶纳米颗粒的制备方法,分析以种晶介导球状的CeO2的形成机理。在生长阶段,CeO2粒子通过初级粒子在其表面的沉积来生长,从而降低了粒子的表面能,导致由许多初级粒子组成的次级粒子的形成。加入的一定量的紧密堆积的种晶聚集体优先作为初级粒子的沉积中心来降低它们的表面能,从而减小次级粒子的尺寸、增加其均匀性以及促进这些次级粒子的形成。  相似文献   
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