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Postharvest Quality and Physiological Behavior of Sweet Potato (Ipomoea batatas Lam.) Leaf Stalks Under Three Temperatures

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Agricultural Sciences in China 2009年第2期8卷 244-248页

作者： PENG Yan xu yong-quan DUAN Dao-fu MAO Lin-chun Department of Food Science and Nutrition College of Biosystem Engineering and Food Science Zhejiang University Hangzhou 310029 P.R.China Tea Research Institute Chinese Academy of Agricultural Sciences Hangzhou 310008 P.R.China Maize Research Institute Zhejiang Academy of Agricultural Sciences Dongyang 322100 P.R.China

Sweet potato （Ipomoea batatas Lam.） leaf stalks were cut into 20 cm length, and stored at 20, 6, and 2℃. The respiration rate, ethylene production, ascorbic acid, free amino acid, total chlorophyll content, freshness, and shelf life were determined during storage to investigate the effect of storage temperatures on the quality and physiological responses in sweet potato leaf stalks. Wound responses were observed as high respiration rate and ethylene production immediately after cutting. Sweet potato leaf stalks were found to be sensitive to chilling injury manifested as browning and water-soaking on the surface at 2℃. In contrast, sweet potato leaf stalks were susceptible to senescence, exhibited by etiolating and yellowing, at 20℃. Loss in weight and chlorophyll was minimized under low temperatures. High temperatures also caused the accumulation of amino acids with a significant loss of ascorbic acid and chlorophyll. Sweet potato leaf stalks had a storage life of 16 days at 6℃, 8 days at 2℃, and 6 days at 20℃, respectively.

关键词： sweet potato leaf stalks storage quality

Effects of Chemical Components on the Amount of Green Tea Cream

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Agricultural Sciences in China 2011年第6期10卷 969-974页

作者： xu yong-quan CHEN Su-qin SHEN Dan-yu YIN Jun-feng Key Laboratory of Machining and Quality Control of Tea and Beverage Plants Ministry of Agriculture/National Engineering Technology Research Center for Tea Industry/Tea Research Institute Chinese Academy of Agrieultural Sciences Hangzhou 310008 P.R.China Shenzhen ShenbaoHuacheng Foods Co. Ltd Shenzhen 518020 P.P.China Research Institute of Subtropical Forestry Chinese Academy of Forestry Fuyang 311400 P.R. China

The relationship between the amount of tea cream and the chemical components contents in the original green tea infusion was investigated. The results showed that the amounts of tea cream in the green tea infusions obtained from different cultivars and different parts of new shoots were varied. There were many chemical components participating in the formation of green tea cream. However, there were only the contents of caffeine （Y=0.85, P〈0.01） and polyphenols （Y=0.65, P〈0.05） in the original green tea infusion highly correlated with the amount of green tea cream. Stepwise regression analysis of overall chemical components indicated that the contents of caffeine and gallated catechins in the original green tea infusion had a significant effect （P〈0.01） on green tea cream levels. Cream （g L-1）=-172.071＋ 0.129×Ccaffeine＋0.024×Ggallated catechins （R2=0.936）. The amount of green tea cream can be predicted by the contents of gallated catechins and caffeine in the original tea infusion. Principal component analysis also indicated that catechins, minerals, and polysaccharides were the important chemical components in the formation of green tea cream.

关键词： green tea infusion chemical components amount of tea cream

Urea-induced interfacial engineering enabling highly reversible aqueous zinc-ion battery

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Rare Metals 2024年第4期43卷 1599-1609页

作者： Bin-Rui xu quan-An Li yong Liu Guang-Bin Wang Zi-He Zhang Feng-Zhang Ren School of Material Science and Engineering Henan University of Science and TechnologyLuoyang471023China School of Information Engineering Henan University of Science and TechnologyLuoyang471023China Longmen Laboratory Luoyang471023China Provincial and Ministerial Co-Construction of Collaborative Innovation Center for Non-Ferrous Metal New Materials and Advanced Processing Technology Luoyang471023China

Aqueous zinc-ion batteries(AZIBs)have been regarded as prospective rechargeable energy storage devices because of the high theoretical capacity and low redox potential of Zn ***,the uncontrollable formation of dendrites and the water-induced side reactions at the Zn/electrolyte interface,and the poor reversibility under a high current density(>2 mA·cm^(-2))and large area capacity(>2 mAh·cm^(-2))still limit the practical applications of ***,a strategy that can overcome these difficulties is urgently ***,we introduce an environmentally friendly and low-cost additive,namely urea,to the electrolyte of AZIBs to induce uniform Zn deposition and suppress the side *** of the adsorption behavior,electrochemical characterization,and observations of the morphology revealed the interfacial modification induced by urea on the Zn/electrolyte interface,demonstrating its huge potential in ***,the long-term cycling stability(over2100 h)of a Zn/Zn symmetric cell under a high current density of 5 mA·cm^(-2)and a capacity of 5 mAh·cm^(-2)was achieved with a 1 mol·L^(-1)ZnSO_(4)electrolyte with the urea ***,the assembled Zn/NH_4V_4O_(10)full cell with urea exhibited excellent cycling performance and an outstanding average Coulombic efficiency of 99.98%.These results indicate that this is a low-cost and effective additive strategy for realizing highly reversible AZIBs.

关键词： Zn anode Urea additive Interface engineering Dendrite growth Side reaction

A survey on facial image deblurring

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Computational Visual Media 2024年第1期10卷 3-25页

作者： Bingnan Wang Fanjiang xu quan Zheng Institute of Software Chinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China

When a facial image is blurred,it significantly affects high-level vision tasks such as face *** purpose of facial image deblurring is to recover a clear image from a blurry input image,which can improve the recognition accuracy,***,general deblurring methods do not perform well on facial ***,some face deblurring methods have been proposed to improve performance by adding semantic or structural information as specific priors according to the characteristics of the facial *** this paper,we survey and summarize recently published methods for facial image deblurring,most of which are based on deep ***,we provide a brief introduction to the modeling of image ***,we summarize face deblurring methods into two categories:model-based methods and deep learning-based ***,we summarize the datasets,loss functions,and performance evaluation metrics commonly used in the neural network training *** show the performance of classical methods on these datasets and metrics and provide a brief discussion on the differences between model-based and learning-based ***,we discuss the current challenges and possible future research directions.

关键词： facial image deblurring model-based deep learning-based semantic or structural prior

中空纤维膜和陶瓷膜过滤处理对咖啡饮料品质的影响研究

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饮料工业 2024年第3期27卷 1-5页

作者：谢关华林家正吕逸凡龙丹洪鹏许勇泉陈佳恒枫食品科技有限公司浙江杭州311200 中国农业科学院茶叶研究所浙江杭州310008

为比较中空纤维膜和陶瓷膜过滤处理对咖啡饮料品质的影响,本文从理化性质分析、感官审评和挥发性化合物分析的角度对过滤后的咖啡饮料进行了比较分析,结果显示,经膜过滤后,咖啡饮料浊度下降,澄清程度升高,中空纤维膜的过滤效果优于陶瓷... 详细信息

为比较中空纤维膜和陶瓷膜过滤处理对咖啡饮料品质的影响,本文从理化性质分析、感官审评和挥发性化合物分析的角度对过滤后的咖啡饮料进行了比较分析,结果显示,经膜过滤后,咖啡饮料浊度下降,澄清程度升高,中空纤维膜的过滤效果优于陶瓷膜,但陶瓷膜的过滤通量高于中空纤维膜。陶瓷膜过滤后咖啡因的下降比例要高于中空纤维膜过滤,两种处理间存在显著性差异。从感官审评结果来看,中空纤维膜过滤后的咖啡饮料香气饱满,滋味较协调醇厚。运用气相色谱质谱联用技术(gas chromatography-mass spectrometry,GC-MS)对膜过滤后的咖啡饮料进行检测,通过统计分析共筛选出8种挥发性化合物,其含量在不同膜过滤处理的咖啡饮料中存在显著性差异。以检出的挥发性成分为自变量,可对两种膜处理的咖啡样品进行较好的区分。在实际生产应用时,需综合考虑原料品质、产品属性、生产成本等因素来选择最适合的过滤方式。

关键词：中空纤维膜陶瓷膜咖啡饮料过滤方式品质

Mechanism analysis of foam penetration in EPB shield tunnelling with a focus on FER and soil particle size

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Underground Space 2024年第4期17卷 170-187页

作者： He Huang quan Sun Tao xu Wanhuan Zhou State Key Laboratory of Internet of Things for Smart City and Department of Civil and Environmental Engineering University of MacaoMacao 999078China Department of Civil and Environmental Engineering University of MacaoMacao 999078China School of Transportation Southeast UniversityNanjing 210000China

Parameters of foam penetration in earth pressure balance(EPB)shield tunnelling,such as permeability coefficients and penetration distances,significantly impact tunnel face ***,existing studies have faced inaccuracies in analysing these parameters due to imitations in experimental *** study addresses this issue by employing enhanced methods for a more precise analysis of foam *** involving three distinct sand types(coarse,medium,and fine)and three foam expansion ratios(FER)(10,15,and 20)are conducted using a modified model test *** from a novel computer vision-based method,the model test outcomes unveil two distinct foam penetration paths:liquid migration(L_(w))and bubble migration(L_(f)).Three penetration phases-namely,injection,blockage&drainage,and breakage—are identified based on L_(w)and L_(f)*** initial"injection"phase conforms to Darcy’s law and is amenable to mathematical *** foam with FER of 15 has the maximum viscosity and,hence the L_(f)and permeability in the penetration tests with FER of 15 are the lowest in the same *** bubble size distribution of foam with different FER shows minor ***,the characteristics of foam penetration vary due to the distinct particle size distribution(PSD)of different *** penetration creates low-permeability layers in both medium and fine sands due to the larger bubble size of the foam compared to the estimated pore sizes of medium and fine *** the coarse sand results in a different situation due to its large pore *** distinctive characteristics of foam penetration in different sand strata are notably shaped by FER,PSD,and pore size *** insights shed light on the complex interactions during foam penetration at the tunnel face,contributing valuable knowledge to EPB shield tunnelling practices.

关键词： EPB Soil conditioning Foam penetration Permeability Tunnel face

The Essential 2-rank for Classical Groups

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2169-2186页

作者： Jian Bei AN yong xu Department of Mathematics University of AucklandAucklandNew Zealand School of Mathematics and Statistics He’nan University of Science and TechnologyLuoyang 471023P.R.China

Let G be a symplectic or orthogonal group defined over a finite field with odd characteristic and let D≤G be a Sylow *** this paper,we classify the essential 2-subgroups and determine the essential 2-rank of the Frobenius category FD(G).Together with the results of An–Dietrich and Cao–An–Zeng,this completes the work of essential subgroups and essential ranks of classical groups.

关键词： Frobenius category conjugation families essential 2-rank symplectic groups orthogonal groups

Preparation and performance evaluation of the slickwater using novel polymeric drag reducing agent with high temperature and shear resistance ability

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Petroleum Science 2024年第2期21卷 1113-1121页

作者： Ming-Wei Zhao Zhen-Feng Ma Cai-Li Dai WeiWu yong-quan Sun xu-Guang Song Yun-Long Cheng Xiang-Yu Wang National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580ShandongChina Shandong Key Laboratory of Oilfield Chemistry China University of Petroleum(East China)Qingdao266580ShandongChina Sinopec Shengli Oilfield Dongying257001ShandongChina Department of Chemical and Materials Engineering University of AlbertaEdmontonAB T6G 1H9Canada East China Petroleum Bureau of Sinopec Nanjing210011JiangsuChina

Slickwater fracturing fluids are widely used in the development of unconventional oil and gas resources due to the advantages of low cost,low formation damage and high drag reduction ***,their performance is severely affected at high *** reducing agent is the key to determine the drag reducing performance of *** this work,in order to further improve the temperature resistance of slickwater,a temperature-resistant polymeric drag reducing agent(PDRA)was synthesized and used as the basis for preparing the temperature-resistant *** slickwater system was prepared with the compositions of 0.2 wt%PDRA,0.05 wt%drainage aid nonylphenol polyoxyethylene ether phosphate(NPEP)and 0.5 wt%anti-expansion agent polyepichlorohydrindimethylamine(PDM).The drag reduction ability,rheology properties,temperature and shear resistance ability,and core damage property of slickwater were systematically studied and *** contrast to on-site drag reducing agent(DRA)and HPAM,the temperature-resistant slickwater demonstrates enhanced drag reduction efficacy at 90℃,exhibiting superior temperature and shear resistance ***,the drag reduction retention rate for the slickwater achieved an impressive 90.52%after a 30-min shearing ***,the core damage is only 5.53%.We expect that this study can broaden the application of slickwater in high-temperature reservoirs and provide a theoretical basis for field applications.

关键词： Unconventional resources Polymeric drag reducing agent Slickwater High drag reduction rate Temperature resistance

Influence of Heat-setting Temperature on the Microporous Structure and Properties of PP/HDPE Bilayer Microporous Membranes

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Chinese Journal of Polymer Science 2024年第8期42卷 1243-1252页

作者： Jie Xie yong-Shi Wu Jia-Yi Xie Rui-Jie xu Cai-Hong Lei Sai-Nan Song Guang-quan Li An-Ping Huang School of Materials and Energy Guangdong University of TechnologyGuangzhou 510006China Lanzhou Petrochemical Research Center Petrochemical Research InsititutePetroChinaLanzhou 730060China School of Chemistry and Civil Engineering Shaoguan CollegeShaoguan 512005China

Due to the mechanical stability of PP layer,the PP/HDPE double-layer microporous mem brane could be prepared at a higher heat-setting temperatu re than that of PE monolayer *** this work,the effects of heat-setting temperature on the pore structure and properties of PP/HDPE dou ble-layer membrane were *** the increase of heat-setting temperature from 120℃to 130℃,the length of connecting bridge crystal and crystallinity in the PE layer increase due to the melting of thin lamellae and the stability of connecting bridge structure during *** corresponding air permeability,po rosity,wetta bility of liquid electrolyte and mechanical property of the heat-set microporous membrane increase,exhibiting better electrochemical ***,when the heat-setting temperature is further increased to 140℃,higher than the melting point of PE resin,some pores are closed since the lamellae and connecting bridges melt and shrink during heat-setting,resulting in a decrease of air permeability and *** contrast,there is negligible change in the PP layer within the above heat-setting temperature *** study successfully builds the relationship between the stable pore structure and property of microporous membrane during heat-setting,which is helpful to guide the production of high-pe rformance PP/PE/PP lithium batteries separator.

关键词： PP/HDPE bilayer microporous membranes Heat-setting temperature SAXS