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Keemun black tea stems and leaves:comparison of chemical characterization and anti-inflammatory activities
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作者 Mengting Zhu Xiaoqing Rong +5 位作者 Mingchun Wen Piaopiao Long Zongde Jiang Wen Xu Daniel Granato Liang Zhang 《Food Science and Human Wellness》 2025年第4期1546-1556,共11页
This work aims to compare the chemical composition and anti-inflammatory effects on RAW264.7 macrophages of Keemun black tea stems and leaves.A total of 50 volatile compounds were identified in tea stems and leaves,an... This work aims to compare the chemical composition and anti-inflammatory effects on RAW264.7 macrophages of Keemun black tea stems and leaves.A total of 50 volatile compounds were identified in tea stems and leaves,and aldehydes,alcohols,and esters were the main volatile compound categories.There were 11 key volatile compounds,including geraniol,benzeneacetaldehyde,methyl salicylate,linalool,etc.contributed to distinguishing the tea stems from the tea leaves.In the quantitative and liquid chromatography-mass spectrometry(LC-MS)-based metabolomics analysis,higher contents of amino acids,monosaccharides,and quinic acids were found in stems than those in leaves.Inversely,higher contents of tea pigments,flavan-3-ols,gallic acid,purine alkaloids,and flavonol glycosides were present in tea leaves than in stems.LC-MS-based metabolomics also revealed that organic acids were the most critical non-volatile compounds responsible for the differences between tea stems and leaves.Furthermore,tea stems had better inhibiting effects of pro-inflammatory cytokines(interleukin(IL)-1βand IL-6)in lipopolysaccharide-challenged RAW264.7 macrophages than tea leaves,while no significant differences exist between leaves and stems for inhibiting the secretion of tumor necrosis factorα(TNF-α)and NO.In conclusion,our results support using Keemun black tea stems as a novel source of anti-inflammatory compounds. 展开更多
关键词 Black tea stems Volatile compounds Non-volatile compounds Anti-inflammatory activities CYTOKINES
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Characterization of mulberry leaf instant tea and evaluation of its hypolipidemia effect via regulation of intestinal microbiota 被引量:2
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作者 Xiaoyun Han Yunlong Bai +3 位作者 Xiaoxin Feng Baochang Du Baojiang Zheng Qingshen Sun 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1348-1357,共10页
The purpose of this study was to characterize mulberry leaf instant tea(MLIT)powder prepared from the'Longsang No.1'(Morus abla L.cv.Longsang 1)mulberry leaves in Heilongjiang Province(China)and assess its obe... The purpose of this study was to characterize mulberry leaf instant tea(MLIT)powder prepared from the'Longsang No.1'(Morus abla L.cv.Longsang 1)mulberry leaves in Heilongjiang Province(China)and assess its obesity-preventing/relieving effects.A total of 174 compounds including quercetin,chlorogenic acid,1-deoxyecomycin(1-DNJ)related to antihyperlipidemia effects were identified from the MLIT powder.MLIT treatment reversed the Lee's index,fat coefficient,and serum biochemical parameters in both the obesity relieving and obesity preventing mice fed with high-fat diet.In the obesity relieving experiment,the relative abundance of Desulfovibrio in mouse feces decreased after both 0.5%and 1%MLIT treatments.In obesity preventing experiments,mouse with different amount of MLIT treatments showed increased relative abundance of Akkermansia,Bifidobacterium and Lactobacillus,while Deferribacteres,Desulfobacterota decreased.The beneficial bacteria in the intestinal tract of mice treated with MLIT increased.This study proved that MLIT had antihyperlipidemia potential via modulating intestinal microbiota in mice. 展开更多
关键词 Mulberry leaf instant tea Liquid chromatography-mass spectrometry(LC-MS) Antihyperlipidemia Intestinal microbiota
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Risk assessment of oil and gas investment environment in countries along the Belt and Road Initiative 被引量:1
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作者 Bao-Jun Tang Chang-Jing Ji +3 位作者 Yu-Xian Zheng Kang-Ning Liu Yi-Fei Ma Jun-Yu Chen 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1429-1443,共15页
With the implementation of the Belt and Road Initiative, China is deepening its cooperation in oil and gas resources with countries along the Initiative. In order to better mitigate risks and enhance the safety of inv... With the implementation of the Belt and Road Initiative, China is deepening its cooperation in oil and gas resources with countries along the Initiative. In order to better mitigate risks and enhance the safety of investments, it is of significant importance to research the oil and gas investment environment in these countries for China's overseas investment macro-layout. This paper proposes an indicator system including 27 indicators from 6 dimensions. On this basis, game theory models combined with global entropy method and analytic hierarchy process are applied to determine the combined weights, and the TOPSIS-GRA model is utilized to assess the risks of oil and gas investment in 76 countries along the Initiative from 2014 to 2021. Finally, the GM(1,1) model is employed to predict risk values for 2022-2025. In conclusion, oil and gas resources and political factors have the greatest impact on investment environment risk, and 12 countries with greater investment potential are selected through cluster analysis in conjunction with the predicted results. The research findings may provide scientific decisionmaking recommendations for the Chinese government and oil enterprises to strengthen oil and gas investment cooperation with countries along the Belt and Road Initiative. 展开更多
关键词 Belt and road Initiative Oil and Gas Investment Risk assessment
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Antibacterial mechanism of kojic acid and tea polyphenols against Escherichia coli O157:H7 through transcriptomic analysis 被引量:1
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作者 Yilin Lin Ruifei Wang +4 位作者 Xiaoqing Li Keren Agyekumwaa Addo Meimei Fang Yehui Zhang Yigang Yu 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期736-747,共12页
Escherichia coli O157:H7 is one of the major foodborne pathogenic bacterial that cause infectious diseases in humans.The previous found that a combination of kojic acid and tea polyphenols exhibited better activity ag... Escherichia coli O157:H7 is one of the major foodborne pathogenic bacterial that cause infectious diseases in humans.The previous found that a combination of kojic acid and tea polyphenols exhibited better activity against E.coli O157:H7 than using either alone.This study aimed to explore responses underlying the antibacterial mechanisms of kojic acid and tea polyphenols from the gene level.The functional enrichment analysis by comparing kojic acid and tea polyphenols individually or synergistically against E.coli O157:H7 found that acid resistance systems in kojic acid were activated,and the cell membrane and genomic DNA were destructed in the cells,resulting in“oxygen starvation”.The oxidative stress response triggered by tea polyphenols inhibited both sulfur uptake and the synthesis of ATP,which affected the bacteria's life metabolic process.Interestingly,we found that kojic acid combined with tea polyphenols hindered the uptake of iron that played an essential role in the synthesis of DNA,respiration,tricarboxylic acid cycle.The results suggested that the iron uptake pathways may represent a novel approach for kojic acid and tea polyphenols synergistically against E.coli O157:H7 and provided a theoretical basis for bacterial pathogen control in the food industry. 展开更多
关键词 Kojic acid tea polyphenols Antibacterial mechanism Escherichia coli O157:H7 RNA-SEQ
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An Analysis on the Reform of the College English Teaching Based on“The Belt and Road”Initiative
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作者 杨金燕 《海外英语》 2019年第9期251-252,共2页
Under the new normal economy of China,“the Belt and Road ”brings challenges as well as opportunities.It also brings challenges for college English teaching. We should analyze the problems of college English teaching... Under the new normal economy of China,“the Belt and Road ”brings challenges as well as opportunities.It also brings challenges for college English teaching. We should analyze the problems of college English teaching under“the Belt and Road”to deepen the reform of the college English teaching and cultivate more high-quality talents. 展开更多
关键词 “The BELT and road” COLLEGE English teaCHING
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Carbonic anhydrase 2 mediates anti-obesity effects of black tea as thermogenic activator
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作者 Peng Ma Jie Xiao +12 位作者 Biyu Hou Ping He Xinyu Yang Yisa Wang Zijing Wang Tianshu Xu Xiuying Yang Xuan Zhu Shasha Xiang Song Li Guanhua Du Jian Ying Guifen Qiang 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第5期2917-2936,共20页
Obesity is a metabolic disorder due to over-accumulation of adipose tissue and ultimately becomes a“disease”.Brown adipose tissue(BAT)thermogenesis and white adipose tissue(WAT)browning emerge as a potential strateg... Obesity is a metabolic disorder due to over-accumulation of adipose tissue and ultimately becomes a“disease”.Brown adipose tissue(BAT)thermogenesis and white adipose tissue(WAT)browning emerge as a potential strategy of anti-obesity by dissipating energy as heat.However,drugs based on adipose tissue thermogenesis have not been successfully approved yet.In current study,we found that black tea extract(BTE)obtained by patentauthorized manufacturing process prevented body weight gain as novel thermogenic activator with reduction of adiposity,improvement of adipose distribution,and glucose metabolism improvement in diet-induced obesity mice.Mechanismly,anti-obesity effect of BTE depends on promoting BAT thermogenesis and WAT browning with upregulation of uncoupling protein 1(UCP1),especially visceral adipose tissue(VAT)with browning resistance.Specifically,utilizing in silico approach of network pharmacology and molecular docking,we identified carbonic anhydrase 2(CA2)in nitrogen metabolism as anti-obesity target of BTE and further elucidated that protein kinase B(AKT)signaling pathway linked CA2 and UCP1.Meanwhile gut microbiota regulation may prompt the CA2-dependent thermogenesis activation.Our findings demonstrated anti-obesity effect of BTE as thermogenic activator through CA2-mediated BAT thermogenesis and WAT browning via CA2-AKT-UCP1 signaling pathway,which could be developed as promising anti-obesity agent with good safety and efficacy. 展开更多
关键词 OBESITY Black tea THERMOGENESIS BROWNING Adipose tissue
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Junshanyinzhen tea extract prevents obesity by regulating gut microbiota and metabolic endotoxemia in high-fat diet fed rats
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作者 Jian Ouyang Xiuping Li +6 位作者 Changwei Liu Danmin Lu Jie Ouyang Fang Zhou Qi Liu Jianan Huang Zhonghua Liu 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期2036-2047,共12页
Obesity is associated with gut dysbiosis and metabolic endotoxin.Junshanyinzhen tea extract(JSTE)reduced fat accumulation and body weight in obese mice.However,the effects and mechanism of JSTE in preventing obesity w... Obesity is associated with gut dysbiosis and metabolic endotoxin.Junshanyinzhen tea extract(JSTE)reduced fat accumulation and body weight in obese mice.However,the effects and mechanism of JSTE in preventing obesity were unclear.Therefore,we used different doses of JSTE(75,150 and 300 mg/(kg·day))to evaluate the effect on high-fat diet(HFD)-induced rats under 8 weeks of intervention.Here,our results showed that JSTE could significantly reduce body weight gain,blood lipid levels and fat accumulation,improve fatty damage in liver tissue(P<0.05).In addition,JSTE increased the expression of intestinal tight junction proteins(P<0.05),relieved metabolic endotoxemia(P<0.05)and chronic low-grade inflammation in HFD rats.Sequencing of fecal samples showed that JSTE could effectively reverse the microbial diversity and the ratio of Firmicutes to Bacteroidetes to normal levels in HFD-fed rats.Desulfovibrioceae and Erysipelotrichaceae,which are positively related to obesity,were decreased by JSTE intervention(P<0.05).while Bifidobacteriaceae,Bacteroidaceae,Akkermansia,and Clostridium,which are negatively related to obesity,were increased.Together,these results suggested that JSTE might effectively prevent obesity by modulating gut microbiota dysbiosis,intestinal barrier dysfunction,metabolic endotoxemia and chronic low-grade infl ammation in HFD-induced rats. 展开更多
关键词 Junshanyinzhen tea OBESITY Gut microbiota Gut barrier function Metabolic endotoxemia
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The modulatory effect of oolong tea polyphenols on intestinal flora and hypothalamus gene expression in a circadian rhythm disturbance mouse model
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作者 Ruonan Yan Chi-Tang Ho +3 位作者 Yanan Liu Shengnan Zhan Zufang Wu Xin Zhang 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期748-764,共17页
The interaction between host circadian rhythm and gut microbes through the gut-brain axis provides new clues for tea polyphenols to improve host health.Our present research showed that oolong tea polyphenols(OTP)impro... The interaction between host circadian rhythm and gut microbes through the gut-brain axis provides new clues for tea polyphenols to improve host health.Our present research showed that oolong tea polyphenols(OTP)improved the structural disorder of the intestinal flora caused by continuous darkness,thereby modulating the production of metabolites related to pyruvate metabolism,glycolysis/gluconeogenesis,and tryptophan metabolism to alleviate the steady-state imbalance.After fecal microbiota transplantation from the OTP group,the single-cell transcriptomic analysis revealed that OTP significantly increased the number of hypothalamus cell clusters,up-regulated the number of astrocytes and fibroblasts,and enhanced the expression of circadian rhythm genes Cry2,Per3,Bhlhe41,Nr1d1,Nr1d2,Dbp and Rorb in hypothalamic cells.Our results confirmed that OTP can actively improve the intestinal environmental state as well as internal/peripheral circadian rhythm disorders and cognitive impairment,with potential prebiotic functional characteristics to notably contribute to host health. 展开更多
关键词 Gut microbiota Circadian rhythm Oolong tea polyphenols Single-cell sequencing Metabolism
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Utilization of Solid Waste Materials as Roadbed Fillers in Road Construction:a Review
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作者 AN Liang CHEN Wenwu +2 位作者 ZHAO Tianyu LI Lunji WANG Yingchun 《材料导报》 EI CAS CSCD 北大核心 2024年第S02期247-253,共7页
China has a large solid waste stockpile and a low resource utilisation rate,and the utilisation of solid waste resources is of great significance in promoting sustainable social development.In order to further promote... China has a large solid waste stockpile and a low resource utilisation rate,and the utilisation of solid waste resources is of great significance in promoting sustainable social development.In order to further promote the green and efficient development of China's road field,an overview of the current status of the application,research progress,hot frontiers,problems and their countermeasures based on the three aspects of industrial solid wastes,engineering solid wastes and municipal solid wastes in highway engineering was conducted,and the development prospect of the resourceful utilisation of solid waste in highway engineering was outlooked,with a view to promoting the development of China's green roads.Statistics on the stockpile,utilisation and comprehensive utilisation rate of industrial solid wastes in China are presented,and the optimal mixing amount,production process and application technology of industrial solid wastes for road base materials are systematically summarised.Based on the concept of high-value utilisation of solid waste,the mechanical properties,durability,construction technology and quality control standards of engineering solid waste applied in roadbed engineering are summarised,and the difficulties in the application of engineering solid waste in road engineering are summarised.Finally,the feasibility,mechanical properties and environmental characteristics of municipal solid waste domestic waste incinerator slag,waste tyres and plastics applied in road engineering are summarised.This review can provide references and lessons for the design and development of green roads,and promote the innovation and development of greening road engineering. 展开更多
关键词 industrial solid waste engineering solid waste municipal solid waste green road
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Research on the Reform of English Teaching Strategies in Higher Voca⁃ tional Colleges under the Belt and Road Initiative
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作者 晏诗洁 《海外英语》 2020年第13期273-274,共2页
With the development of economic globalization and the implementation of the Belt and Road Economic Development Strategy,China's foreign economic exchanges will become more frequent,and the demand for English prof... With the development of economic globalization and the implementation of the Belt and Road Economic Development Strategy,China's foreign economic exchanges will become more frequent,and the demand for English professionals will also in⁃crease.Judging from the current situation of English teaching in higher vocational education,higher vocational English education in our country cannot meet the needs of social development.It is necessary to proceed from the actual situation.While strengthen⁃ing the education of students'basic knowledge of English,they should also train students'practical application ability and culti⁃vate for the society.More talents are available to meet the needs of social development. 展开更多
关键词 The Belt and road Initiative higher vocational English teaching strategy
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Advancing Internationalization:Actively Pursuing a Shared Vision-An Examination of CPP’s Dynamic Involvement in the Belt and Road Initiative
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作者 Niu Jianing 《China Oil & Gas》 CAS 2024年第3期61-66,共6页
On September 7,2013,President Xi Jinping proposed the significant initiative of jointly building the Silk Road Economic Belt.On October 3,2013,President Xi proposed the major initiative of jointly building the 21st Ce... On September 7,2013,President Xi Jinping proposed the significant initiative of jointly building the Silk Road Economic Belt.On October 3,2013,President Xi proposed the major initiative of jointly building the 21st Century Maritime Silk Road.Since its inception in the autumn of 2013,the Belt and Road initiative,envisioned as a monumental project carrying the mission of the era,has turned a new page in the global development process.Over the past 11 years,China Petroleum Pipeline Engineering Co.,Ltd.(CPP)has thoroughly implemented the strategic deployment of China National Petroleum Corporation(CNPC),actively fulfilled its corporate responsibilities,and embraced high-quality participation in the Belt and Road Initiative as its mission.By fully leveraging its international advantages,CPP has continuously contributed“pipeline strength”to the high-quality joint construction of the Belt and Road. 展开更多
关键词 jointly road thoroughly
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基于语料库的麦卡锡小说The Road 汉译本对比
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作者 王雪利 《英语广场(学术研究)》 2024年第16期11-16,共6页
美国作家麦卡锡的小说The Road描述了一对父子在末日情景下的求生之路,被称为是一部“残酷的诗学”。本文以小说原文和两个中文译本为语料,自建英汉平行语料库,并结合定量分析和定性分析,对比分析两个汉译本的异同及其原因。研究发现,... 美国作家麦卡锡的小说The Road描述了一对父子在末日情景下的求生之路,被称为是一部“残酷的诗学”。本文以小说原文和两个中文译本为语料,自建英汉平行语料库,并结合定量分析和定性分析,对比分析两个汉译本的异同及其原因。研究发现,杨博译本比毛雅芬译本用词更简单、句子更简短、阅读难度更低;两位译者均常用省译法和语序调整法;杨译本倾向于异化翻译策略,采用直译法、增译法等准确传达原文意思,语言表达更为正式;毛译本则遵循归化翻译策略,采用合译法、意译法等增强译文的可读性和文学性。 展开更多
关键词 The road 语料库 翻译
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我国茶产业低碳化发展研究与实践进展 被引量:1
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作者 胡强 唐晏 +4 位作者 朱迪 张优 王志博 陈超 陈富桥 《中国茶叶》 2025年第1期21-28,共8页
“双碳”目标下,我国农业的绿色发展模式转型是实现碳达峰和碳中和目标的必然选择。茶业是农业固碳减排的重要领域之一,探索茶产业低碳化发展是践行国家“双碳”战略的重要抓手。文章从茶叶低碳研究进展、茶叶低碳生产的探索与研究、生... “双碳”目标下,我国农业的绿色发展模式转型是实现碳达峰和碳中和目标的必然选择。茶业是农业固碳减排的重要领域之一,探索茶产业低碳化发展是践行国家“双碳”战略的重要抓手。文章从茶叶低碳研究进展、茶叶低碳生产的探索与研究、生态低碳茶的认证与推广、茶园碳汇研究等方面,总结了我国利用茶园生态系统发挥其碳汇功能和推动茶产业绿色低碳发展的“双碳”研究与实践经验,分析了我国茶产业践行“双碳”战略中存在的不足,进而提出了推进我国茶产业低碳化发展的对策与建议,以期为我国茶产业高质量发展提供支撑与依据。 展开更多
关键词 “双碳”战略 茶产业 生态低碳茶 生态低碳认证 对策建议
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新式茶饮消费者消费行为特征调查与分析 被引量:1
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作者 林梦星 唐晏 +1 位作者 阎鹏翔 陈富桥 《中国茶叶》 2025年第1期37-42,共6页
基于消费调研数据,深入剖析新式茶饮消费者消费行为特征,凝练驱动新式茶饮行业快速发展的营销策略,进而提出新式茶饮对促进传统茶产业创新发展的启示。调研发现,新式茶饮消费者具有产品需求多元化、消费诉求健康化、消费价格理性化、消... 基于消费调研数据,深入剖析新式茶饮消费者消费行为特征,凝练驱动新式茶饮行业快速发展的营销策略,进而提出新式茶饮对促进传统茶产业创新发展的启示。调研发现,新式茶饮消费者具有产品需求多元化、消费诉求健康化、消费价格理性化、消费渠道便捷化的消费行为特征,因此传统茶产业创新发展需立足消费者多元化的产品需求,回应消费者健康化的消费诉求,顺应消费者理性化的消费价格趋势,迎合消费者便捷化的消费渠道偏好,同时提高地理标志与企业品牌融合度。 展开更多
关键词 新式茶饮 消费行为特征 传统茶产业 创新发展 启示
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中国茶叶出口贸易特征、问题及对策分析 被引量:1
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作者 赵青松 郭怡康 《中国茶叶》 2025年第1期29-36,共8页
中国是全球最大的茶叶生产国、消费国和主要出口国。文章基于最新海关数据库HS编码,筛选并汇总绿茶、红茶、乌龙茶、普洱熟茶、黑茶、白茶、其他花茶和茉莉花茶8类产品的出口贸易额和出口量,重点分析中国各类茶叶的出口贸易特征、主要... 中国是全球最大的茶叶生产国、消费国和主要出口国。文章基于最新海关数据库HS编码,筛选并汇总绿茶、红茶、乌龙茶、普洱熟茶、黑茶、白茶、其他花茶和茉莉花茶8类产品的出口贸易额和出口量,重点分析中国各类茶叶的出口贸易特征、主要贸易伙伴和主要出口省份。研究发现,红茶和绿茶占据中国茶叶出口的主要地位,但其出口规模呈现逐年下降趋势,黑茶、茉莉花茶和白茶则出现较快增长,各类茶叶的主要贸易伙伴和出口省份与茶叶自身属性紧密相关。当前中国面临新型贸易壁垒、茶叶标准体系不完善、茶企品牌建设滞后和产业规模大而不精等问题,严重影响中国茶叶出口。针对上述问题,文章提出完善茶叶质量安全标准体系,以促进绿色生产转型升级;加强国际品牌建设,提升中国茶企品牌知名度;推动全产业链数智一体化,持续深化供给侧改革等对策建议。 展开更多
关键词 茶叶 出口 茶类 海关 贸易壁垒
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基于网络凝聚子群分析的万里茶道沿线古村落集群式保护利用研究——以湖北省五峰县为例
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作者 袁磊 雷靛 +1 位作者 刘晗 刘小虎 《新建筑》 2025年第1期99-105,共7页
五峰县作为万里茶道上重要的节点,探索其古村落的集群式保护利用模式,有利于文化线路沿线古村落的保护与利用。文章运用MCR最小阻力模型和网络分析方法,采用“集群—核心村—核心廊道”的逻辑顺利展开研究,探索五峰县古村落的集群分布... 五峰县作为万里茶道上重要的节点,探索其古村落的集群式保护利用模式,有利于文化线路沿线古村落的保护与利用。文章运用MCR最小阻力模型和网络分析方法,采用“集群—核心村—核心廊道”的逻辑顺利展开研究,探索五峰县古村落的集群分布特征。结果显示:(1)五峰县万里茶道与当今的交通布局高度契合;(2)五峰县古村落大多集中分布在西部武陵山脉地区,基本沿古茶道呈现“大分散、小聚集”的线性分布特征;(3)基于五峰县集群网络计算得出4个凝聚子群、6个核心村、1条核心廊道。进而提出“以点带面、连线成片”的综合集群式保护利用策略。 展开更多
关键词 文化线路 万里茶道 传统村落 集中连片 网络分析
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不同施肥处理对老茶园土壤改良及茶叶品质的影响研究
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作者 杜颖颖 林海裕 +5 位作者 张俊 谢思宇 谢细和 高海燕 苏小琴 杨秀芳 《中国茶叶加工》 2025年第1期48-56,共9页
针对老茶园土壤酸化板结现象严重的问题,设置4个不同施肥处理方式,分析研究施肥模式对老茶园土壤以及茶叶品质的影响,筛选出适合严重酸化的老茶园土壤改良方案。结果表明,有机肥、无机肥的配施,和生物炭的施用可将土壤pH值分别提高0.72... 针对老茶园土壤酸化板结现象严重的问题,设置4个不同施肥处理方式,分析研究施肥模式对老茶园土壤以及茶叶品质的影响,筛选出适合严重酸化的老茶园土壤改良方案。结果表明,有机肥、无机肥的配施,和生物炭的施用可将土壤pH值分别提高0.72和0.30。有机肥、无机肥配施对土壤中氮、磷、钾等元素类含量和微生物活性的提升有明显的影响。与对照相比,有机肥和无机肥配施后,两年春茶水浸出物含量提高1.5%和3.05%,茶多酚含量提高0.67%和2.2%,茶氨酸含量提高0.08%和0.32%,施用生物炭和生物炭、有机肥配施对水浸出物、茶氨酸等含量的提升也有较显著影响。感官分析显示,生物炭、有机肥配施对老茶园茶叶品质提升效果最为明显,其次为有机肥和无机肥配施。因此,酸化现象严重的老茶园可选用有机肥和生物炭配施,或者有机肥和无机肥配施的方式。文章为酸化老茶园土壤改良提供了理论依据。 展开更多
关键词 老茶园 土壤 施肥 茶叶品质
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活性炭净化-离子色谱法测定茶水及茶饮料中氟含量及其健康风险评估
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作者 吴梅 陈祝军 +4 位作者 陈蓉 秦园 吴建兵 张珊 王露 《食品安全质量检测学报》 2025年第1期44-52,共9页
目的建立分析纯活性炭净化-离子色谱法检测茶水及茶饮料中氟离子含量的方法,进而研究茶水及茶饮料对人体健康风险。方法将6种茶叶分别以两种方式冲泡进行实验,方式一:按时间梯度冲泡茶叶;方式二:一次投茶,多次加水冲泡茶叶,收集茶水。... 目的建立分析纯活性炭净化-离子色谱法检测茶水及茶饮料中氟离子含量的方法,进而研究茶水及茶饮料对人体健康风险。方法将6种茶叶分别以两种方式冲泡进行实验,方式一:按时间梯度冲泡茶叶;方式二:一次投茶,多次加水冲泡茶叶,收集茶水。茶水及茶饮料,经活性炭净化,0.45μm微孔滤膜过滤,以4.5 mmol/L碳酸钠和0.8 mmol/L碳酸氢钠溶液为淋洗液,经AS23离子色谱柱(4.0 mm×250 mm)分离,离子色谱进行检测。以冲泡方式一获得的最高茶氟溶出量,冲泡方式二获得的总茶氟溶出量以及茶饮料中氟含量分别进行健康风险评估。结果在最佳分析条件下,本法氟离子的检出限为0.016 mg/L;在0.1~5.0 mg/L质量浓度范围内的线性关系良好,相关系数(r^(2))为0.9996;加标回收率94.93%~105.32%;相对标准偏差1.02%~2.13%(n=6)。本方法检测茶叶中氟离子的溶出量,发现茶叶中氟离子的溶出量均随冲泡时间的延长不断增加达到最高值;随冲泡次数的增加,茶叶中氟离子的溶出量先增加,之后下降的趋势逐渐变缓。前2次冲泡氟离子溶出率可达茶氟总溶出量的65%以上。结论该方法灵敏度高,准确性好,操作简单,具有实用价值。以该法检测6种茶叶在两种冲泡方式下获得的茶氟日摄入量以及茶饮料中茶氟日摄入量均符合我国和世界卫生组织推荐的氟日摄入量限值要求;目标危险因素(target hazard quotient,THQ)均小于1,对人体没有显著健康风险。建议减少茶叶浸泡时间,洗茶,选用优质茶叶来科学健康饮茶。 展开更多
关键词 活性炭 离子色谱法 茶水 茶饮料
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基于SIR模型的城市路网拥堵传播分析
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作者 郑长江 周思达 +3 位作者 郑树康 马庚华 张博 戴津雯 《郑州大学学报(工学版)》 CAS 北大核心 2025年第1期51-58,共8页
研究城市道路交通拥堵传播规律对缓解交通拥堵问题有着积极作用,为此建立了基于SIR的城市道路交通拥堵传播模型,用以分析城市道路交通拥堵传播过程。首先,基于城市实际路网构建路网对偶拓扑网络,并依据SIR建立交通拥堵传播模型。其次,... 研究城市道路交通拥堵传播规律对缓解交通拥堵问题有着积极作用,为此建立了基于SIR的城市道路交通拥堵传播模型,用以分析城市道路交通拥堵传播过程。首先,基于城市实际路网构建路网对偶拓扑网络,并依据SIR建立交通拥堵传播模型。其次,结合道路网络的复杂网络特征和道路自身的相关属性,引入随机森林算法计算相关权重,确定拥堵模型中的传播速率等关键参数。最后,以南京市秦淮区某区域路网为例,构建有69个节点,163条连线的城市路网对偶拓扑网络进行仿真实验。结果表明:道路节点度和道路饱和度是影响道路拥堵传播的关键因素,道路节点度的影响相对较小,传播范围增长在5%以内,恢复时间影响在10%左右;道路饱和度的影响相对较大,随着道路饱和度的增长,传播范围增长最大可至40%,恢复时间影响在20%左右。 展开更多
关键词 SIR模型 城市交通 拥堵传播 道路节点度 道路饱和度
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中黄1号加工不同造型黄茶的品质比较
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作者 敖存 师大亮 +3 位作者 牛小军 张霖 郭敏明 赵芸 《浙江农业科学》 2025年第1期160-163,共4页
为了解加工黄茶的适制性,开发不同造型的黄茶产品,提升产业活力。将中黄1号茶树品种鲜叶加工成5种不同造型的黄茶产品,通过感官审评和理化成分测定分析,结果表明,中黄1号具有良好的黄茶适制性,加工卷曲形和朵形黄茶品质更佳,色泽嫩黄鲜... 为了解加工黄茶的适制性,开发不同造型的黄茶产品,提升产业活力。将中黄1号茶树品种鲜叶加工成5种不同造型的黄茶产品,通过感官审评和理化成分测定分析,结果表明,中黄1号具有良好的黄茶适制性,加工卷曲形和朵形黄茶品质更佳,色泽嫩黄鲜润,香气嫩甜,滋味甘醇,带汤香。不同做形工艺对黄茶品质的影响较大,对其理化成分溶出的影响大于对其绝对含量的影响。过长的做形时间会明显增加酯型儿茶素浓度,从而增加苦涩味,降低滋味品质。 展开更多
关键词 做形工艺 黄茶 品质
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