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51.
Qiang Xia Tao Feng Xiaowei Lou Ying Wang Yangying Sun Daodong Pan Jinxuan Cao 《International Journal of Food Science & Technology》2020,55(2):669-680
As a decisive attribute, flavour could be influenced by HP treatments through multiple physical and chemical pathways within the high pressure (HP)-assisted meat curing process. This investigation aimed to identify the major pathway influencing volatile flavour patterns of two representative vinasse-cured duck (VCD) products with HP treatments (150–300 MPa/15 min), including wet and dry types, by employing headspace fingerprinting as an untargeted approach. Results suggested that HP treatments greatly lowered moisture contents and increased Warner-Bratzler shear force and thiobarbituric acid reactive substances of the cured samples. According to multivariate models, the volatile flavour patterns of the HP-processed VCD could be clearly separated from the unprocessed samples, but the VCD pressurised at different intensities represented similar volatile fingerprinting, which was validated by e-nose analysis. The discriminant analysis (OPLS-DA) model outlined vinasse-derived ethanol, acetic acid, 3-methyl-1-butanol, 2-methyl-1-butanol, phenethyl alcohol and 2-methyl-3-octanone as the major discriminant aromas across the unpressurised and pressurised samples. 相似文献
52.
An Al–Zn–Mg–Cu (Al-7B04) aluminium alloy in two conditions, i.e. with an artificial aging (7B04-AA) temper and with an annealing (7B04-O) temper, was friction-stir processed using water cooling, and the microstructure and the mechanical properties of the stir zone (SZ) were investigated. Compared with the samples subjected to air cooling, the SZs of water-cooled samples were strengthened, and the degree of strengthening depended on the initial base metal temper. For friction-stir-processed material after an 7B04-O temper, the efficiency of strengthening was relatively high due not only to the refinement of grains and strengthening precipitates but also due to the high solution level in the SZ. In contrast, the slight strengthening of friction-stir-processed 7B04-AA resulted solely from grain refinement. 相似文献
53.
Ronen Gottesman Angang Song Igal Levine Maximilian Krause A. T. M. Nazmul Islam Daniel Abou‐Ras Thomas Dittrich Roel van de Krol Abdelkrim Chemseddine 《Advanced functional materials》2020,30(21)
A new method for enhancing the charge separation and photo‐electrochemical stability of CuBi2O4 photoelectrodes by sequentially depositing Bi2O3 and CuO layers on fluorine‐doped tin oxide substrates with pulsed laser deposition (PLD), followed by rapid thermal processing (RTP), resulting in phase‐pure, highly crystalline films after 10 min at 650 °C, is reported. Conventional furnace annealing of similar films for 72 h at 500 °C do not result in phase‐pure CuBi2O4. The combined PLD and RTP approach allow excellent control of the Bi:Cu stoichiometry and results in photoelectrodes with superior electronic properties compared to photoelectrodes fabricated through spray pyrolysis. The low photocurrents of the CuBi2O4 photocathodes fabricated through PLD/RTP in this study are primarily attributed to their low specific surface area, lack of CuO impurities, and limited, slow charge transport in the undoped films. Bare (without protection layers) CuBi2O4 photoelectrodes made with PLD/RTP shows a photocurrent decrease of only 26% after 5 h, which represents the highest stability reported to date for this material. The PLD/RTP fabrication approach offers new possibilities of fabricating complex metal oxides photoelectrodes with a high degree of crystallinity and good electronic properties at higher temperatures than the thermal stability of glass‐based transparent conductive substrates would allow. 相似文献
54.
命名实体识别是自然语言处理中的热点研究方向之一,目的是识别文本中的命名实体并将其归纳到相应的实体类型中。首先阐述了命名实体识别任务的定义、目标和意义,分析提出了命名实体识别的主要难点在于领域命名实体识别局限性、命名实体表述多样性和歧义性、命名实体的复杂性和开放性;然后介绍了命名实体识别研究的发展进程,从最初的规则和字典方法到传统的统计学习方法再到现在的深度学习方法,不断地将新技术应用到命名实体识别研究中以提高性能;接着系统梳理了当下命名实体识别任务中的若干热门研究点,分别是匮乏资源下的命名实体识别、细粒度命名实体识别、嵌套命名实体识别以及命名实体链接;最后针对评判命名实体识别模型的好坏,总结了常用的若干数据集和实验测评指标,并给出了未来的研究建议。 相似文献
55.
56.
《Oil and Energy Trends》2019,44(3):43-47
Values of net oil imports(-)/exports for Austria, Belgium, Denmark, Finland, France, Germany, Italy, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, the United Kingdom, Japan, Canada, the United States and Australia. Updated on a monthly basis. Number of imports for Belgium, France, Germany, Greece, Republic of Ireland, Italy, Netherlands, Portugal, Spain, Sweden, the United Kingdom, and Other EU-15 (EU-15), Norway, Poland, Switzerland, Turkey, and Other Europe (OECD Europe), Canada, Chile, Mexico, and the United States (OECD Western Hemisphere), and Australia, Japan, Republic of Korea, New Zealand, (OECD Asia-Pacific), and Total OECED. Current data for Austria, Belgium, Finland, France, Germany, Greece, Italy, Netherlands, Portugal, Spain, Sweden, the United Kingdom, Other EU-15 (EU-15), Czech Republic, Hungary, Poland, Slovakia, Turkey, and Other Europe (OECD Europe), Canada, Mexico, and the United States (OECD Western Hemisphere), Australia, Japan, Republic of Korea, and New Zealand (OECD Asia-Pacific). Updated on a monthly basis. Current data for principal importers of natural gas and the amount in which they import from United States, Republic of Korea, United Kingdom, France, Japan, Italy, Germany and Spain (Table 19.1). Current data for principal exporters of natural gas and the amount they export to Canada, Trinidad and Tobago, the United States, Netherlands, Norway, Russia, Turkmenistan, Qatar, Algeria, Nigeria, Indonesia, Malaysia and Australia (Table 19.2). Updated on a monthly basis. 相似文献
57.
Yin Bao Lie Tang Matthew W. Breitzman Maria G. Salas Fernandez Patrick S. Schnable 《野外机器人技术杂志》2019,36(2):397-415
Sorghum (Sorghum bicolor) is known as a major feedstock for biofuel production. To improve its biomass yield through genetic research, manually measuring yield component traits (e.g. plant height, stem diameter, leaf angle, leaf area, leaf number, and panicle size) in the field is the current best practice. However, such laborious and time‐consuming tasks have become a bottleneck limiting experiment scale and data acquisition frequency. This paper presents a high‐throughput field‐based robotic phenotyping system which performed side‐view stereo imaging for dense sorghum plants with a wide range of plant heights throughout the growing season. Our study demonstrated the suitability of stereo vision for field‐based three‐dimensional plant phenotyping when recent advances in stereo matching algorithms were incorporated. A robust data processing pipeline was developed to quantify the variations or morphological traits in plant architecture, which included plot‐based plant height, plot‐based plant width, convex hull volume, plant surface area, and stem diameter (semiautomated). These image‐derived measurements were highly repeatable and showed high correlations with the in‐field manual measurements. Meanwhile, manually collecting the same traits required a large amount of manpower and time compared to the robotic system. The results demonstrated that the proposed system could be a promising tool for large‐scale field‐based high‐throughput plant phenotyping of bioenergy crops. 相似文献
58.
《Oil and Energy Trends》2019,44(10):45-49
Values of net oil imports(-)/exports for Austria, Belgium, Denmark, Finland, France, Germany, Italy, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, the United Kingdom, Japan, Canada, the United States and Australia. Updated on a monthly basis. Number of imports for Belgium, France, Germany, Greece, Republic of Ireland, Italy, Netherlands, Portugal, Spain, Sweden, the United Kingdom, and Other EU-15 (EU-15), Norway, Poland, Switzerland, Turkey, and Other Europe (OECD Europe), Canada, Chile, Mexico, and the United States (OECD Western Hemisphere), and Australia, Japan, Republic of Korea, New Zealand, (OECD Asia-Pacific), and Total OECED. Current data for Austria, Belgium, Finland, France, Germany, Greece, Italy, Netherlands, Portugal, Spain, Sweden, the United Kingdom, Other EU-15 (EU-15), Czech Republic, Hungary, Poland, Slovakia, Turkey, and Other Europe (OECD Europe), Canada, Mexico, and the United States (OECD Western Hemisphere), Australia, Japan, Republic of Korea, and New Zealand (OECD Asia-Pacific). Updated on a monthly basis. Current data for principal importers of natural gas and the amount in which they import from United States, Republic of Korea, United Kingdom, France, Japan, Italy, Germany and Spain (Table 19.1). Current data for principal exporters of natural gas and the amount they export to Canada, Trinidad and Tobago, the United States, Netherlands, Norway, Russia, Turkmenistan, Qatar, Algeria, Nigeria, Indonesia, Malaysia and Australia (Table 19.2). Updated on a monthly basis. 相似文献
59.
60.
白云岩与砂岩致密储集体质量的差异性 总被引:2,自引:0,他引:2
白云岩与砂岩致密储集体质量参数为随机分布的连续谱系,孔隙结构、物理参数复杂多变,表征难度较大。基于铸体薄片、压汞、核磁共振、孔隙度和渗透率等测试技术,结合大量天然气勘探开发实际资料,采用统计分析对比方法,重点讨论了储层质量宏观与微观参数特征。结果表明,白云岩与砂岩致密储集体质量参数具有正态分布特征,是一种金字塔数据结构,常规储层比例一般为15%~20%,是砂岩或白云岩致密储层的“甜点”;致密砂岩储层微观孔隙发育,孔、喉连通性较好,分布比较均匀,储层孔、渗关系较好,表现为相对高孔和低渗;白云岩致密储层质量尽管具有孔、喉连通性差和孔、渗关系较差的不利因素,但也具有相对高渗、低束缚水饱和度、低排驱压力及裂缝网络发育等有利因素,天然气渗流能力较好,勘探开发潜力较大。我国发育碳酸盐岩沉积,应加强致密白云岩气藏成藏条件研究与勘探。 相似文献