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Non-destructive study of fruits using grating-based X-ray imaging
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作者 Sheng-Xiang Wang Ren-Fang Hu +5 位作者 Kun Gao Faiz Wali Gui-Bin Zan Da-Jiang Wang Zhi-Yun Pan Shi-Qiang Wei 《Nuclear Science and Techniques》 SCIE CAS CSCD 2017年第2期57-60,共4页
Grating-based X-ray imaging can make use of conventional tube sources to provide absorption, refraction and scattering contrast images from a single set of projection images efficiently. In this paper, a fresh cherry ... Grating-based X-ray imaging can make use of conventional tube sources to provide absorption, refraction and scattering contrast images from a single set of projection images efficiently. In this paper, a fresh cherry tomato and a dried umeboshi are imaged by using X-ray Talbot–Lau interferometer. The seed distribution in the scattering image of the cherry tomato, and the wrinkles of epicarp in the refraction image of the umeboshi, are shown distinctly. The refraction and scattering images provide more information on subtle features than the absorption image. Also, the contrast-to-noise ratio values show distinguishing capacity of the three kinds of imaging techniques. The results confirm that grating-based X-ray imaging is of great potential in non-destructive fruit testing. 展开更多
关键词 non-DESTRUCTIVE TESTING X-ray imaging Talbot–Lau INTERFEROMETER FRUIT TESTING
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光谱技术在果品无损检测中的应用研究进展
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作者 李明 孙小旭 +5 位作者 顾红 李兰 程大伟 王勇健 代占武 陈锦永 《江西农业学报》 CAS 2024年第1期122-128,共7页
介绍了常用的果品无损检测方法,包括电子鼻法、X射线计算机断层成像法、机械方法、磁共振(核磁共振)成像光谱学法、拉曼光谱学法、近红外光谱技术等;重点综述了高光谱成像技术在无损检测水果结构特性、生化成分和安全性等方面的研究进展... 介绍了常用的果品无损检测方法,包括电子鼻法、X射线计算机断层成像法、机械方法、磁共振(核磁共振)成像光谱学法、拉曼光谱学法、近红外光谱技术等;重点综述了高光谱成像技术在无损检测水果结构特性、生化成分和安全性等方面的研究进展,以期为水果品质的无损检测研究提供参考。 展开更多
关键词 水果 品质 高光谱成像技术 无损检测技术
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Comparative Analysis of Climatic Change Trend and Change-Point Analysis for Long-Term Daily Rainfall Annual Maximum Time Series Data in Four Gauging Stations in Niger Delta
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作者 Masi G. Sam Ify L. Nwaogazie +4 位作者 Chiedozie Ikebude Jonathan O. Irokwe Diaa W. El Hourani Ubong J. Inyang Bright Worlu 《Open Journal of Modern Hydrology》 2023年第4期229-245,共17页
The aim of this study is to establish the prevailing conditions of changing climatic trends and change point dates in four selected meteorological stations of Uyo, Benin, Port Harcourt, and Warri in the Niger Delta re... The aim of this study is to establish the prevailing conditions of changing climatic trends and change point dates in four selected meteorological stations of Uyo, Benin, Port Harcourt, and Warri in the Niger Delta region of Nigeria. Using daily or 24-hourly annual maximum series (AMS) data with the Indian Meteorological Department (IMD) and the modified Chowdury Indian Meteorological Department (MCIMD) models were adopted to downscale the time series data. Mann-Kendall (MK) trend and Sen’s Slope Estimator (SSE) test showed a statistically significant trend for Uyo and Benin, while Port Harcourt and Warri showed mild trends. The Sen’s Slope magnitude and variation rate were 21.6, 10.8, 6.00 and 4.4 mm/decade, respectively. The trend change-point analysis showed the initial rainfall change-point dates as 2002, 2005, 1988, and 2000 for Uyo, Benin, Port Harcourt, and Warri, respectively. These prove positive changing climatic conditions for rainfall in the study area. Erosion and flood control facilities analysis and design in the Niger Delta will require the application of Non-stationary IDF modelling. 展开更多
关键词 Rainfall Time Series Data Climate Change Trend Analysis Variation Rate Change Point Dates non-Parametric Statistical Test
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无损检测技术在水果品质安全和真实性的应用研究进展
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作者 肖宏辉 李春霖 +3 位作者 张永志 聂晶 吴振 袁玉伟 《核农学报》 CAS CSCD 2024年第4期736-745,共10页
在水果产量攀升和品质要求不断提高的背景下,对水果的品质、安全和真实性开展快速无损检测的需求日益迫切。本研究概述了光谱学、力学、声学、计算机视觉、电子鼻和电子舌等无损检测技术结合多种化学计量学方法在水果营养功效成分和感... 在水果产量攀升和品质要求不断提高的背景下,对水果的品质、安全和真实性开展快速无损检测的需求日益迫切。本研究概述了光谱学、力学、声学、计算机视觉、电子鼻和电子舌等无损检测技术结合多种化学计量学方法在水果营养功效成分和感官属性品质特征挖掘、农药残留和病害霉变安全性检测以及原产地、品种分类、贮藏时间真实性鉴别研究中的应用。同时,本研究还从生产实际和科学研究两个方面进行了展望,可为水果的质量安全监管和消费者权益保障提供科学依据。 展开更多
关键词 水果 品质评价 安全性 真实性 无损检测
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长江上游近61年来水文干旱演变特征及归因
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作者 李帅 曾凌 +3 位作者 熊斌 曹瑞 龚文婷 朱文丽 《水力发电学报》 CSCD 2024年第2期33-45,共13页
水文干旱受气候变化和人类活动的共同影响,揭示变化环境下水文干旱演变特征及驱动机制,有助于提高防旱抗旱能力。基于长江上游1960—2020年长系列气象水文数据,采用多模型集合模拟重建天然径流并计算标准化径流指数,采用广义可加模型构... 水文干旱受气候变化和人类活动的共同影响,揭示变化环境下水文干旱演变特征及驱动机制,有助于提高防旱抗旱能力。基于长江上游1960—2020年长系列气象水文数据,采用多模型集合模拟重建天然径流并计算标准化径流指数,采用广义可加模型构建时变标准化径流指数,通过指数对比定量区分气候变化和人类活动对水文干旱的影响。结果表明:长江上游水文干旱自然演变总体呈加剧态势,人类活动进一步加剧了旱情;长江上游水文干旱演变驱动因子表现出明显的时空差异,气候变化是金沙江、沱江和乌江流域年尺度水文干旱演变的主导因子,人类活动是岷江、嘉陵江和整个上游流域年尺度水文干旱演变的主导因子,季节尺度主导因子与年尺度并不完全一致。 展开更多
关键词 水文干旱 气候变化 人类活动 集合模拟 非一致性 长江上游
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数字零工非体面工作感知与主动服务行为
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作者 阚卓凡 陈嘉茜 赵曙明 《经济与管理研究》 2024年第4期76-92,共17页
本文基于认知评估理论,通过对460名数字零工的多期追踪调研,重点探讨数字零工非体面工作感知与主动服务行为的关系及内在机制。研究结果表明,非体面工作感知负向影响数字零工的主动服务行为,挑战性评估和工作重塑在非体面工作感知和主... 本文基于认知评估理论,通过对460名数字零工的多期追踪调研,重点探讨数字零工非体面工作感知与主动服务行为的关系及内在机制。研究结果表明,非体面工作感知负向影响数字零工的主动服务行为,挑战性评估和工作重塑在非体面工作感知和主动服务行为之间起链式中介作用;雇佣关系氛围在非体面工作感知和挑战性评估关系中起调节作用,并且通过减弱非体面工作感知对挑战性评估的负向影响,调节挑战性评估和工作重塑在非体面工作感知与主动服务行为之间的链式中介作用。本文的研究结论不仅丰富了非体面工作感知和主动服务行为的相关研究,也可为平台管理者如何推动数字零工展现主动服务行为提供借鉴。 展开更多
关键词 数字零工 非体面工作感知 认知评估 工作重塑 主动服务行为 雇佣关系氛围
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China's INDC and non-fossil energy development 被引量:6
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作者 HE Jian-Kun 《Advances in Climate Change Research》 SCIE CSCD 2015年第3期210-215,共6页
Global climate change promotes the energy system reform. Achieving a high proportion of renewable energy becomes the major countries' energy strategy. As proposed in its Intended Nationally Determined Contribution... Global climate change promotes the energy system reform. Achieving a high proportion of renewable energy becomes the major countries' energy strategy. As proposed in its Intended Nationally Determined Contributions(INDC), China intends to raise the proportion of non-fossil energy in primary energy consumption to about 20% by 2030. That ambitious goal means the non-fossil energy supplies by 2030 will be 7-8 times that of 2005, and the annual increase rate is more than 8% within the 25 years. Besides, the capacity of wind power, solar power, hydropower and nuclear power reaches 400 GW, 350 GW, 450 GW, and 150 GW respectively, and China's non-fossil power capacity is even greater than the U.S.'s total power capacity. In addition, the scale of natural gas increases. Consequently, by 2030, the proportion of coal falls from the current 70% to below 50%, and the CO_2 intensity of energy consumption decreases by 20% compared with the level of 2005, which play important roles in significantly reducing the CO_2 intensity of GDP. Since China has confirmed to achieve the CO_2 emissions peak around 2030,at that time, the newly added energy demand will be satisfied by non-fossil energy, and the consumption of fossil fuel will stop growing. By2030, non-fossil energy accounts for 20%, and the large scale and sound momentum of new and renewable energy industry will support the growth of total energy demand, which plays a key role in CO_2 emissions peaking and beginning to decline, and lays the foundation for establishing a new energy system dominated by new and renewable energy in the second half of the 21 st century as well as finally achieving the CO2zero-emission. 展开更多
关键词 化石能源 中国 可再生能源产业 二氧化碳排放 发电能力 能源消耗 能源需求 太阳能发电
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Beneficial effects of date palm fruits on neurodegenerative diseases
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作者 Musthafa Mohamed Essa Mohammed Akbar Mohammed Abdul Sattar Khan 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第7期1071-1072,共2页
Date palm tree(Phoenix dactylifera L.)is an important crop,which is cultivated in many countries extending from North Africa to the Middle East,including many of the GCC(Gulf Cooperation Council)Countries(Allaith,2008... Date palm tree(Phoenix dactylifera L.)is an important crop,which is cultivated in many countries extending from North Africa to the Middle East,including many of the GCC(Gulf Cooperation Council)Countries(Allaith,2008).Date palm trees have been growing for the last 5,000 years in harshest climatic condition and their fruits have been an excellent 展开更多
关键词 神经退行性疾病 有益作用 棕榈 粮食作物 推广种植 委员会 GCC 椰树
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Hurricane damage assessment for residential construction considering the non-stationarity in hurricane intensity and frequency
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作者 WANG Cao LI Quanwang +2 位作者 PANG Long ZOU Aming ZHANG Long 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第12期110-118,共9页
Natural hazards such as hurricanes may cause extensive economic losses and social disruption for civil structures and infrastructures in coastal areas, implying the importance of understanding the construction perform... Natural hazards such as hurricanes may cause extensive economic losses and social disruption for civil structures and infrastructures in coastal areas, implying the importance of understanding the construction performance subjected to hurricanes and assessing the hurricane damages properly. The intensity and frequency of hurricanes have been reported to change with time due to the potential impact of climate change.In this paper, a probability-based model of hurricane damage assessment for coastal constructions is proposed taking into account the non-stationarity in hurricane intensity and frequency. The nonhomogeneous Poisson process is employed to model the non-stationarity in hurricane occurrence while the non-stationarity in hurricane intensity is reflected by the time-variant statistical parameters(e.g., mean value and/or standard deviation), with which the mean value and variation of the cumulative hurricane damage are evaluated explicitly. The Miami-Dade County, Florida, USA, is chosen to illustrate the hurricane damage assessment method proposed in this paper. The role of non-stationarity in hurricane intensity and occurrence rate due to climate change in hurricane damage is investigated using some representative changing patterns of hurricane parameters. 展开更多
关键词 hurricane DAMAGE assessment intensity frequency non-stationarity CLIMATE change
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On Some Regularities of One-seeded Fruits Evolution
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作者 Tatyana I. Kravtsova 《Journal of Life Sciences》 2015年第11期511-520,共10页
关键词 进化规律 果实 种子 扫描电子显微镜 光学显微镜 形态学基础 组织学 解剖结构
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Determination of Harvest Maturity for Mango (<i>Mangifera indica</i>L.) Fruit by Non-Destructive Criteria
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作者 Moomin Abu Nana Sakyiwa Olympio Joseph Ofei Darko 《Agricultural Sciences》 2021年第10期1103-1118,共16页
Haden, Kent, Palmer, and Keitt mango varieties were studied to establish the relationship of harvest time to 1) seasonal accumulated day-degrees or heat units (<span style="white-space:nowrap;">&#7... Haden, Kent, Palmer, and Keitt mango varieties were studied to establish the relationship of harvest time to 1) seasonal accumulated day-degrees or heat units (<span style="white-space:nowrap;">&#730;</span>C), 2) daily rainfall amount (mm), and 3) physical fruit development attributes in order to fix maturity standards for export and local markets. Randomized Complete Block Design with four replications was used. In each case of Haden, Kent, Palmer, and Keitt varieties, physical fruit development attributes established as standard harvest maturity values were: weight (640 g, 836 g, 837 g, and 1104 g, respectively), length (16.31 cm, 16.19 cm, 21.22 cm, and 19 cm, respectively), width (30.97 cm, 33.47 cm, 30.86 cm, and 35.91 cm, respectively), volume (598 cm<sup>3</sup>, 807 cm<sup>3</sup>, 772 cm<sup>3</sup>, and 959 cm<sup>3</sup>, respectively), density (1.147 g/cm<sup>3</sup>, 1.076 g/cm<sup>3</sup>, 1.084 g/cm<sup>3</sup>, and 1.189 g/cm<sup>3</sup>, respectively), and indentation (0.25 cm, 0.49 cm, and 0.50 cm, respectively). The intensity of grooves around the stylar-scar end of Palmer fruits was studied and used as maturity index. Index values of 0.075 mls, 0.150 mls, 0.425 mls, and 0.116 mls, respectively, for Haden, Kent, Palmer, and Keitt varieties were recorded as latex exuded at harvest since these values tallied with the other physical harvest maturity index values, and also with those of rain fall and temperature values. Temperature, rainfall, and physical characteristics are therefore important non-destructive criteria for fixing maturity index values for mango fruits. 展开更多
关键词 Harvest Maturity Mango Fruit non-DESTRUCTIVE CRITERIA
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Identification of Large Deletion of Ccs Responsible for Non-Red Fruit Color in Pepper (Capsicum annuum) and Development of DNA Marker to Distinguish the Deletion
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作者 Shiho Omori Tsuneo Sasanuma 《American Journal of Plant Sciences》 CAS 2022年第9期1233-1246,共14页
Chili pepper (Capsicum spp.) fruit color is an important agronomical trait. It has been known that a large deletion in the 5' upstream region of the Ccs gene generates non-red fruit color in pepper, but the accura... Chili pepper (Capsicum spp.) fruit color is an important agronomical trait. It has been known that a large deletion in the 5' upstream region of the Ccs gene generates non-red fruit color in pepper, but the accurate size and position of the deletion and whether all the non-red cultivars had the same large deletion or not were unclarified. In this study, to identify the Ccs upstream large deletion, we carried out diagnostic PCR using six forward primers at 300 - 900 bp intervals in the 5' untranslated region of Ccs with a fixed reverse primer for a yellow fruit pepper “Sonia Gold”. Then it was revealed that 4430 bp from -3234 bp position in upstream region to 1196 bp position in exon was deleted in Ccs of “Sonia Gold”. The allele having this deletion was named ccs-del. Probably this allele is substantially the same as ccs-p1 having 4879 bp deletion reported previously. Based on the sequence determined, we developed a PCR marker to distinguish ccs-del. Genotyping of 16 cultivars of C. annuum showed that 14 had ccs-del and the remaining two had another mutant allele ccs-3. This result indicates that ccs-del is the most common allele and widely shared in non-red fruit cultivars in C. annuum. Genotyping of 16 cultivars of C. chinense clarified that one cultivar each possessed ccs-del and ccs-3. These results indicate that major alleles responsible for non-red fruit color in C. annuum were shared across species throughout interspecific introgression. 展开更多
关键词 non-Red Fruit Pepper CCS Identification of Large Deletion ccs-3 Development of DNA Marker
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Fruit-Based Non-Dairy Beverage: A New Approach for Probiotics
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作者 Izabela Alves Gomes Armando Venâncio +1 位作者 Janine Passos Lima Otniel Freitas-Silva 《Advances in Biological Chemistry》 2021年第6期302-330,共29页
<span style="font-family:Verdana;">The growing interest of consumers in using foods that improve health has motivated researchers and the food industry to develop new functional products such as foods ... <span style="font-family:Verdana;">The growing interest of consumers in using foods that improve health has motivated researchers and the food industry to develop new functional products such as foods with probiotics. Probiotic cultures, for example, from lactic acid bacteria and bifidobacteria have been highlighted for their ability to promote balance in the intestinal microbiota as well as other benefits such as anticarcinogenic and antimutagenic effects, reduced plasma cholesterol levels, decreased symptoms of lactose intolerance, and stimulation of the immune </span><span style="font-family:Verdana;">response. Traditionally, probiotics are incorporated into dairy products.</span><span style="font-family:Verdana;"> However, because of the growing number of individuals affected by lactose into</span><span style="font-family:Verdana;">lerance and/or vegans, other food matrices have been studied as potential</span><span style="font-family:Verdana;"> car</span><span style="font-family:Verdana;">riers for these microorganisms. Considering all the facts mentioned above, cereals, legumes, fruits, and vegetables could be potential substrates, where</span><span style="font-family:Verdana;"> probiotic bacteria can be used for the development of non-dairy beverages. This review aimed to highlight the research carried out on 1) probiotic micro-organisms, including the more recent reclassification according to their phylogenetic position, 2) probiotic beverages from non-dairy sources which emerged as an alternative for lactose-intolerant consumers and, 3) the aspects of improving the gut microbiota.</span> 展开更多
关键词 Functional Foods Fruit Juice Lactobacillus non-Dairy Beverages Gut Microbiota
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广西腺枝葡萄‘桂黑珍珠3号’果实品质差异解析
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作者 李洪艳 成果 +7 位作者 吴代东 梁翡翠 张劲 谢林君 谭宗琨 杨鑫 韦志勇 蒙仙 《中外葡萄与葡萄酒》 北大核心 2023年第6期10-17,共8页
以罗城和武鸣生产的腺枝葡萄‘桂黑珍珠3号’为试材,结合两地的气候条件,调查该品种在两地的物候期、果实品质与气候因子的差异。结果显示,葡萄生长季(4—9月)的有效积温、采收前3个月平均温度之和、光照时数3个指标以武鸣较高,浆果成... 以罗城和武鸣生产的腺枝葡萄‘桂黑珍珠3号’为试材,结合两地的气候条件,调查该品种在两地的物候期、果实品质与气候因子的差异。结果显示,葡萄生长季(4—9月)的有效积温、采收前3个月平均温度之和、光照时数3个指标以武鸣较高,浆果成熟月降水量和采收前2个月水热系数以罗城较高;武鸣‘桂黑珍珠3号’各物候期开始时间早于罗城6~17 d;罗城‘桂黑珍珠3号’成熟果实的果粒大、种子多,白藜芦醇和单宁含量指标优于武鸣;另外,罗城成熟期果实中检出的挥发性代谢物种类和含量总体高于武鸣,尤其以芳樟醇和α-松油醇两个具有典型花香类的萜类化合物含量更高。相关分析表明,‘桂黑珍珠3号’果实粒质量除与纵径、横径和芳樟醇含量呈极显著正相关外,还与果实L^(*)和α-松油醇含量呈显著正相关,与a^(*)呈显著负相关;果实籽粒数、籽质量和皮质量与白藜芦醇和单宁含量无显著相关性。综上认为,相对气温低、海拔高是罗城腺枝葡萄‘桂黑珍珠3号’物候期晚、生育期长、酚类及挥发性化合物丰富的主要原因。 展开更多
关键词 腺枝葡萄 桂黑珍珠3号 气候因子 果实品质
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世界贸易组织法视域下的美欧232钢铝协议与中国应对 被引量:1
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作者 胡建国 曾齐玉 《经贸法律评论》 2023年第2期65-85,共21页
2021年10月31日达成的美欧232钢铝协议包括“钢铝关税配额安排”和“全球钢铝贸易安排”两项内容,引发全球关注。该协议可能与WTO规则发生冲突:美国根据“钢铝关税配额安排”给予欧盟钢铝产品的关税配额涉嫌违反GATT核心义务,且很难根... 2021年10月31日达成的美欧232钢铝协议包括“钢铝关税配额安排”和“全球钢铝贸易安排”两项内容,引发全球关注。该协议可能与WTO规则发生冲突:美国根据“钢铝关税配额安排”给予欧盟钢铝产品的关税配额涉嫌违反GATT核心义务,且很难根据其安全例外条款获得正当性;“全球钢铝贸易安排”预想的基于低碳强度标准的钢铝产品进口限制亦涉嫌违反GATT核心义务,很难根据其环保例外条款获得正当性,或者为了获得正当性需要满足第20条(g)项和序言施加的系列条件。钢铝关税配额安排对我国钢铝产品对美出口影响不大,但可能影响232钢铝关税相关WTO争端的解决进程,且消除了美欧结盟遏制中国的一大障碍。中国单独起诉前述钢铝关税配额的意义不大,但仍应通过不同渠道质疑其WTO合法性。全球钢铝贸易安排如全面实施,将会对我国钢铝产品出口产生显著负面影响;连接贸易与气候变化、非市场导向问题的全球钢铝贸易安排很可能只是一个“行业试点”,类似安排有可能复制到其他行业,这会对国际经贸规则演进及我国对外贸易产生深远影响。作为回应,中国应明确反对诸如全球钢铝贸易安排的“小圈子”做法,坚决反对全球钢铝贸易安排中的不合理因素,密切关注全球钢铝贸易安排的谈判和实施进展并质疑其合法性,同时应努力提高国内钢铝生产的清洁度。 展开更多
关键词 美欧232钢铝协议 钢铝关税配额安排 全球钢铝贸易安排 气候变化 非市场导向
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西番莲果皮花色苷对H_(2)O_(2)诱导L02细胞氧化损伤的抑制作用 被引量:3
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作者 张佳辰 丁蕾 +2 位作者 何传波 魏好程 熊何健 《食品安全质量检测学报》 CAS 北大核心 2023年第2期198-207,共10页
目的探究西番莲果皮花色苷(peel of passion fruits anthocyanins,PPFA)对H_(2)O_(2)诱导人正常肝细胞L02氧化损伤的抑制作用。方法采用噻唑蓝[3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide,MTT]法建立H_(2)O_(2)诱导... 目的探究西番莲果皮花色苷(peel of passion fruits anthocyanins,PPFA)对H_(2)O_(2)诱导人正常肝细胞L02氧化损伤的抑制作用。方法采用噻唑蓝[3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide,MTT]法建立H_(2)O_(2)诱导L02细胞氧化损伤的模型,通过测定细胞丙二醛(malondialdehyde,MDA)、乳酸脱氢酶(lactate dehydrogenase,LDH)、超氧化物歧化酶(superoxide dismutase,SOD)、过氧化氢酶(catalase,CAT)和谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-Px)指标,观察PPFA对细胞氧化损伤的抑制作用,结合非靶向代谢组学显著差异代谢物分析,探讨其抗氧化机制。结果PPFA体外清除1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基的半抑制浓度(half maximal inhibitory concentration,IC_(50))值为34.62μg/m L,有一定的羟自由基、超氧阴离子自由基清除能力。细胞实验表明,PPFA能够显著提高H_(2)O_(2)损伤的L02细胞总抗氧化力(P<0.05),并显著降低损伤细胞中MDA生成量和LDH的释放量(P<0.05);与损伤组相比,PPFA各剂量组SOD活性均显著升高(P<0.05),中剂量组CAT与低剂量组GSH-Px的活性显著升高且达空白组水平(P<0.05)。代谢组学分析表明,与损伤组相比,PPFA处理后细胞存在23种显著差异代谢物,涉及到谷胱甘肽代谢、胆汁分泌、铁死亡和脂肪酸生物合成途径。结论PPFA对H_(2)O_(2)诱导L02细胞的氧化损伤有抑制作用,表现出显著的细胞抗氧化活性。 展开更多
关键词 西番莲果皮 花色苷 L02细胞 抗氧化活性 非靶向代谢组学
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‘黑比诺’、‘马瑟兰’和‘北红’葡萄酚类物质差异研究 被引量:2
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作者 李光宗 马军 +1 位作者 雷昊 单守明 《食品与发酵工业》 CAS CSCD 北大核心 2023年第18期125-133,共9页
酚类物质对葡萄和葡萄酒的品质至关重要,以‘黑比诺’、‘马瑟兰’和‘北红’为试材,分别于转色初期、盛期、成熟期和采收期采样,测定果实中总酚、黄烷醇和黄酮醇等指标,并进行主成分分析(principal component analysis,PCA)和正交偏最... 酚类物质对葡萄和葡萄酒的品质至关重要,以‘黑比诺’、‘马瑟兰’和‘北红’为试材,分别于转色初期、盛期、成熟期和采收期采样,测定果实中总酚、黄烷醇和黄酮醇等指标,并进行主成分分析(principal component analysis,PCA)和正交偏最小二乘判别分析(orthogonal partial least squares-discriminant analysis,OPLS-DA)。结果表明,3个品种总酚、总单宁和总花色苷含量因品种特性在成熟过程中呈不同变化趋势;采收时,3个品种中黄烷醇为主要单体酚,‘黑比诺’显著高于‘马瑟兰’和‘北红’,分别高63.97%和66.77%,儿茶素为主要成分;羟基苯甲酸为3个品种中含量第二高类酚,‘北红’显著高于‘黑比诺’和‘马瑟兰’,分别高12.27%和28.31%,主要成分为香草酸;‘马瑟兰’中黄酮醇显著高于‘北红’和‘黑比诺’,是‘北红’和‘黑比诺’的1.91倍和3.13倍;白藜芦醇表现为‘马瑟兰’>‘北红’>‘黑比诺’。对3个品种采收期单体酚含量进行PCA和OPLS-DA,筛选出差异物质主要为黄烷醇类。该研究针对不同品种酚类物质进行分析,为品种选育及酿酒品质提升提供参考。 展开更多
关键词 红色酿酒葡萄 果实品质 酚类物质 非花色苷类酚 品种特性
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基于非平稳GEV模型的黄河源区枯季径流演变特征分析 被引量:2
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作者 江善虎 任明明 +5 位作者 章二子 马明卫 王孟浩 刘亚婷 丁雨 任立良 《河海大学学报(自然科学版)》 CAS CSCD 北大核心 2023年第2期1-7,63,共8页
为剖析气候变化对水文极值非平稳性的影响,采用5 a滑动平均和Mann-Kendall突变检验法对黄河唐乃亥水文站1957—2018年最枯多日平均流量进行非平稳检验;根据Kendall等级相关分析法优选气候指数,以时间和气候指数为协变量构建非平稳广义... 为剖析气候变化对水文极值非平稳性的影响,采用5 a滑动平均和Mann-Kendall突变检验法对黄河唐乃亥水文站1957—2018年最枯多日平均流量进行非平稳检验;根据Kendall等级相关分析法优选气候指数,以时间和气候指数为协变量构建非平稳广义极值分布(generalized extreme value,GEV)模型,并进行参数估计与模型优选,对比平稳与非平稳GEV模型在枯季径流模拟中的应用效果。研究结果表明:黄河源区枯季径流呈现明显的非平稳特征;平稳GEV模型的模拟值偏高,以西太平洋指数为协变量的非平稳GEV模型对极值的拟合效果较好,且能较好地解释极端枯水事件的波动性。 展开更多
关键词 非平稳GEV模型 枯季径流 气候因子 演变特征 黄河源区
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青梅果实成熟期间特征性主香成分的积累分析
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作者 刘敏欣 刘畅 +3 位作者 王鹰翔 杨丽丽 李方坤 李景明 《食品科学》 EI CAS CSCD 北大核心 2023年第14期344-351,共8页
以四川省大邑县大青梅为研究对象,利用顶空-固相微萃取-气相色谱-质谱联用技术和香气活性值分析确定其特征性主香,结合香气前体和气候因子关联分析,探究主香成分在成熟期间的积累规律。结果显示,丁酸乙酯、β-月桂烯、3-甲基-丁酸乙酯... 以四川省大邑县大青梅为研究对象,利用顶空-固相微萃取-气相色谱-质谱联用技术和香气活性值分析确定其特征性主香,结合香气前体和气候因子关联分析,探究主香成分在成熟期间的积累规律。结果显示,丁酸乙酯、β-月桂烯、3-甲基-丁酸乙酯、苯甲醛和壬醛是四川大邑地区大青梅的主要特征香气物质;C_(6)、C_(9)类化合物是其特征性主香成分,C_(6)类香气物质与不饱和脂肪酸前体的相关性较高,且C_(6)和C_(9)类香气物质合成存在正相关。气候显著影响果实成熟期间的香气积累,果实成熟前期降水量是C_(6)类物质含量的关键影响因素,主要影响结合态己烯醇类物质的积累;成熟后期气温对己醇、己酸等游离态物质含量影响较大。研究结果为后续开展青梅精深加工中风味、品质分析,探究气候因素对青梅及其产品的影响,为风味检测实现原料、加工产品的产区判别,积累基础。 展开更多
关键词 青梅 香气 果实成熟 香气前体物质 气候
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脱落酸调控果实成熟的分子及信号转导机制研究进展 被引量:3
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作者 李翠 侯柄竹 《果树学报》 CAS CSCD 北大核心 2023年第5期988-999,共12页
脱落酸(abscisicacid,ABA)作为一种重要的植物激素,不仅涉及许多植物发育过程和逆境胁迫,而且在果实成熟,尤其是非呼吸跃变型果实成熟中发挥关键作用。随着植物中ABA合成、代谢和作用机制的解析及其受体识别和核心信号转导模型的建立,... 脱落酸(abscisicacid,ABA)作为一种重要的植物激素,不仅涉及许多植物发育过程和逆境胁迫,而且在果实成熟,尤其是非呼吸跃变型果实成熟中发挥关键作用。随着植物中ABA合成、代谢和作用机制的解析及其受体识别和核心信号转导模型的建立,极大地推动了ABA在果实成熟和品质形成中的研究。一般来讲,褪绿和着色是果实成熟过程中普遍存在的现象,这一过程涉及了ABA早期信号和多种激素的协同作用并组成了复杂的网络调控机制。总之,ABA是调控果实成熟的核心机制,其中存在着乙烯依赖(呼吸跃变型)和不依赖(非呼吸跃变型)类型。综述了ABA在植物体内的合成、代谢及作用的分子机制,构建了ABA调控果实成熟的分子网络模型,为果实的品质改善和保鲜奠定理论基础。 展开更多
关键词 果实成熟 脱落酸 (非)呼吸跃变型 乙烯 生长素 信号转导
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