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Effects of ultrasonic-assisted extraction on bioactive compounds,volatile flavors and antioxidant activities of vine tea water extracts

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Traditional Medicine Research 2025年第1期10卷 73-81页

作者： Xiao-Long Zhou Wei-jin jiang ji Yu Mao-Jun Yao Yun-Tong Li Hunan Provincial Key Laboratory of Research Resource Mining and High-valued Utilization on Edible&Medicinal PlantCollege of Chemistry and Chemical EngineeringJishou UniversityJishou 416000China Hunan Gaoge Dairy Co. Ltd.Changsha 410000China

Background:Ampelopsis grossedentata,vine tea,which is the tea alternative beverages in *** vine tea processing,a large amount of broken tea is produced,which has low commercial ***:This study investigates the influence of different extraction methods(room temperature water extraction,boiling water extraction,ultrasonic-assisted room temperature water extraction,and ultrasonic-assisted boiling water extraction,referred to as room temperature water extraction(RE),boiling water extraction(BE),ultrasonic assistance at room temperature water extraction(URE),and ultrasonic assistance in boiling water extraction(UBE))on the yield,dihydromyricetin(DMY)content,free amino acid composition,volatile aroma components,and antioxidant properties of vine tea ***:A notable influence of extraction temperature on the yield of vine tea extracts(P<0.05),with BE yielding the highest at 43.13±0.26%,higher than that of RE(34.29±0.81%).Ultrasound-assisted extraction significantly increased the DMY content of the extracts(P<0.05),whereas DMY content in the RE extracts was 59.94±1.70%,that of URE reached 66.14±2.78%.Analysis revealed 17 amino acids,with L-serine and aspartic acid being the most abundant in the extracts,nevertheless ultrasound-assisted extraction reduced total free amino acid *** chromatography-mass spectrometry analysis demonstrated an increase in the diversity and quantity of compounds in the vine tea water extracts obtained through ultrasonic-assisted ***,69 and 68 volatile compounds were found in URE and UBE extracts,which were higher than the number found in RE and BE *** vitro,antioxidant activity assessments revealed varying antioxidant capacities among different extraction methods,with RE exhibiting the highest DPPH scavenging rate,URE leading in ABTS•+free radical scavenging,and BE demonstrating superior ferric ion reducing antioxidant ***:The findings suggest that extraction methods signi

关键词： vine tea dihydromyricetin ultrasonic-assisted extraction volatile aroma components

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Use of additive and pretreatment to control odors in municipal kitchen waste during aerobic composting

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Journal of Environmental Sciences 2015年第11期27卷 83-90页

作者： jing Yuan Qingyuan Yang zhiye Zhang Guoxue Li Wenhai Luo Difang Zhang College of Resources and Environmental Science China Agricultural University School of Civil Mining and Environmental Engineering University of Wollongong

The effects of adding a bulking agent and chemically pretreating municipal kitchen waste before aerobic composting were studied using a laboratory-scale system. The system used20-L reactors and each test lasted 28 days. The objective was to decrease NH3 and H2S emissions during composting. The bulking agent, dry cornstalks, was mixed with the kitchen waste to give a mixture containing 15%（wet weight） bulking agent. A combined treatment was also conducted, in which kitchen waste mixed with the bulking agent was pretreated with ferric chloride（FeC l3）. Less leachate was produced by the composted kitchen waste mixed with bulking agent than by the kitchen waste alone, when the materials had reached the required maturity. The presence of cornstalks also caused less H2 S to be emitted, but had little impact on the amount of NH3 emitted. The FeC l3 was found to act as an effective chemical flocculant,and its presence significantly decreased the amounts of NH3 and H2S emitted. Kitchen waste mixed with cornstalks and treated with FeC l3 emitted 42% less NH3 and 76% less H2 S during composting than did pure kitchen waste.

关键词： Aerobic composting Kitchen waste Pretreatment Ammonia Hydrogen sulfide

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肉苁蓉种子离散元仿真参数标定

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农机化研究 2025年第2期47卷 19-26,53页

作者：白志业蒙贺伟彭慧杰戚江涛李亚萍坎杂石河子大学机械电气工程学院新疆石河子832000

为寻求肉苁蓉种子离散元模型的物料特性参数,采用物理和仿真试验相结合的方法,以不同物性参数组合下肉苁蓉种子休止角为响应值,采用Plackett-Burman试验对参数进行筛选,获取显著性参数,即肉苁蓉种间静摩擦因数、肉苁蓉种间动摩擦因数、... 详细信息

为寻求肉苁蓉种子离散元模型的物料特性参数,采用物理和仿真试验相结合的方法,以不同物性参数组合下肉苁蓉种子休止角为响应值,采用Plackett-Burman试验对参数进行筛选,获取显著性参数,即肉苁蓉种间静摩擦因数、肉苁蓉种间动摩擦因数、肉苁蓉种子-钢板静摩擦因数、肉苁蓉种子-钢板恢复系数。通过Box-Behnken试验建立休止角与显著性参数回归模型并优化,获取接触参数最优值,即肉苁蓉种间静摩擦因数为0.65、肉苁蓉种间动摩擦因数为0.07、肉苁蓉种子-钢板恢复因数为0.54、肉苁蓉种子-钢板静摩擦因数为0.43。通过仿真与物理试验对比验证,得到二者相对误差为2.05%,表明标定参数可为肉苁蓉种子播种机械仿真提供数据依据。

关键词：肉苁蓉种子休止角离散元参数标定播种机械

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认知空间映射及其神经机制

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心理科学进展 2025年第1期33卷 62-76页

作者：吴际李会杰南宁师范大学教育科学学院南宁530001 中国科学院行为科学重点实验室(中国科学院心理研究所) 北京100101 中国科学院大学心理学系北京100049

认知地图不仅可以映射物理空间,还可以支持认知空间映射,形成包括感知空间、情景记忆空间、概念空间和社会空间等在内的跨不同信息领域的地图式表征。认知空间映射的神经机制包括海马体对潜在结构的抽象和概括、支持分布式位置地图的生... 详细信息

认知地图不仅可以映射物理空间,还可以支持认知空间映射,形成包括感知空间、情景记忆空间、概念空间和社会空间等在内的跨不同信息领域的地图式表征。认知空间映射的神经机制包括海马体对潜在结构的抽象和概括、支持分布式位置地图的生成、将信息与背景结构捆绑,以及海马体与其它脑区的协同。未来研究应关注预测性的认知空间地图、海马体对不同精度和层级信息的表征、认知空间映射微观和介观层面的研究空缺以及物理空间和认知空间映射的共同机制和特异性机制等问题。

关键词：认知地图网格细胞位置细胞海马体

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A weighted voltage model predictive control method for a virtual synchronous generator with enhanced parameter robustness

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Protection and Control of Modern Power Systems 2021年第1期6卷 482-492页

作者： Leilei Guo zhiye Xu Nan jin Yanyan Li Wei Wang College of Electric and Information Engineering Zhengzhou University of Light IndustryZhengzhouChina

To address the problem of insufficient system inertia and improve the power quality of grid-connected inverters,and to enhance the stability of the power system,a method to control a virtual synchronous generator(VSG)output voltage based on model predictive control(MPC)is *** of the inductors,capacitors and other components of the VSG can vary as the temperature and current *** the VSG output voltage and power control accuracy using the conventional MPC method may be *** this paper,to improve the parameter robustness of the MPC method,a new weighted predictive capacitor voltage control method is *** detailed theoretical analysis,the principle of the proposed method to reduce the influence of parameter errors on voltage tracking accuracy is ***,the effectiveness and feasibility of the proposed method are verified by experimental tests using the Typhoon control hardware-in-the-loop experimental platform.

关键词： Virtual synchronous generator Model predictive control Optimal voltage vector Parameter error compensation

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Cloning and Characterization of the Microspore Development-Related Gene BcMF2 in Chinese Cabbage Pak-Choi （Brassica campestris L. ssp. chinensis Makino）

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Journal of Integrative Plant Biology 2005年第7期47卷 863-872页

作者： Yong-QinWANG Wan-zhiye jia-ShuCAO Xiao-LinYU XunXIANG GangLU InstituteofVegetableScience ZhejiangUniversityHangzhou310029China／／BeijingAgro-biotechnologyCenterBeijng100089China InstituteofVegetableScience ZhejiangUniversityHangzhou310029China

: For the sake of providing some important information relevant to the study of the molecular mechanism of genic male sterility in plants, gene differential expression in flower buds at different developmental stages, as well as in rosette leaves, florescence leaves, and scapes was analyzed using cDNA amplified fragment length polymorphism (cDNA-AFLP) in the genic male sterile A and fertile B line of Chinese cabbage pak-choi. Following amplification of 125 pairs of primer combinations, 11 differential fragments were obtained, of which eight were from the B line and the other three were from the A line. Of 11 differential fragments, four were verified by Northern hybridization that were expressed preferentially in fertile flower buds. Results of GenBank BLAST showed that one fragment was with unknown function, whereas the other fragments have strong nucleotide sequence similarities with the polygalacturonase (PG) gene, the pectinesterase (PE) gene, and the polygalacturonase inhibitory protein (PGIP4) gene. Only full-length cDNA from the differential fragment BcMF-A18T16-1 was amplified by rapid amplification of cDNA ends (RACE) and Northern analysis showed that this fragment was expressed only in medium and large-sized flower buds of the B line. The full-length cDNA, designated as BcMF2 (Brassica campestris Male Fertile 2), was 1 485 bp long and was composed of a 1 263-bp open reading frame, which had 83% nucleotide similarity to a PG gene from Arabidopsis encoding polygalacturonase. Analysis of the basic structure of the protein revealed that it had one polygalacturonase active site (RVTCGPGHGLSVGS) at 256th site of amino acids and was classified as being a member of family 28 of the glycosyl hydrolases. The role of the BcMF2 gene on microspore development is discussed in the present paper.

关键词： BcMF2 (Brassica campestris Male Fertile 2) gene cDNA amplified fragment length polymorphism Chinese cabbage pak-choi genic male sterility

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集成深度强化学习在股票指数投资组合优化中的应用分析

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计算机科学与探索 2025年第01期19卷 237-244页

作者：冀中张文嘉天津大学电气自动化与信息工程学院天津大学佐治亚理工深圳学院

基于集成深度强化学习的投资组合选择是当前量化金融领域的关键技术之一。然而，目前采用上一窗口阶段最优指标决定下一阶段代理的集成滚动窗口方法存在一定的滞后性。为了有效应对这一不足，提出了双层嵌套集成深度强化学习方法。该方... 详细信息

基于集成深度强化学习的投资组合选择是当前量化金融领域的关键技术之一。然而，目前采用上一窗口阶段最优指标决定下一阶段代理的集成滚动窗口方法存在一定的滞后性。为了有效应对这一不足，提出了双层嵌套集成深度强化学习方法。该方法对三种代理（优势演员-评论员、深度确定性策略梯度和近端策略优化）进行两层嵌套模式，第一层集成通过最优化夏普比率进行阶段模型选择，第二层通过加权投票的方法集成三种深度强化学习算法，从单次训练中收集多个模型快照，在训练期间利用这些模型进行集成预测。分别对上证50投资指数和道琼斯指数及其包含的股票进行了投资组合研究，将持有指数被动策略和均值方差投资组合策略作为基线策略。实验采用了投资组合价值、年化回报率、年化波动率、最大回撤和夏普比率等指标作为对比指标。结果表明，所提出的集成方法在实用性和有效性上表现出较好的性能。

关键词：股票投资组合交易策略深度强化学习双层嵌套集成深度强化学习方法集成学习

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Error Sensitivity Analysis in 10–30-Day Extended Range Forecasting by Using a Nonlinear Cross-Prediction Error Model

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Journal of Meteorological Research 2017年第3期31卷 567-575页

作者： zhiye XIA Lisheng XU Hongbin CHEN Yongqian WANG jinbao LIU Wenlan FENGl college of resources and environment chengdu university of information technologyChengdu 610225 plateau atmosphere and environment key laboratory of sichuan province Chengdu 610225 key laboratory of middle atmosphere and global environment observation institute of atmospheric physicschinese academy of sciencesBeijing 100029

Extended range forecasting of 10-30 days, which lies between medium-term and climate prediction in terms of timescale, plays a significant role in decision-making processes for the prevention and mitigation of disastrous met- eorological events. The sensitivity of initial error, model parameter error, and random error in a nonlinear cross- prediction error （NCPE） model, and their stability in the prediction validity period in 1 0-30-day extended range fore- casting, are analyzed quantitatively. The associated sensitivity of precipitable water, temperature, and geopotential height during cases of heavy rain and hurricane is also discussed. The results are summarized as follows. First, the initial error and random error interact. When the ratio of random error to initial error is small （10＂5-10-2）, minor vari- ation in random error cannot significantly change the dynamic features of a chaotic system, and therefore random er- ror has minimal effect on the prediction. When the ratio is in the range of 10-1-2 （i.e., random error dominates）, at- tention should be paid to the random error instead of only the initial error. When the ratio is around 10 2-10-1, both influences must be considered. Their mutual effects may bring considerable uncertainty to extended range forecast- ing, and de-noising is therefore necessary. Second, in terms of model parameter error, the embedding dimension m should be determined by the factual nonlinear time series. The dynamic features of a chaotic system cannot be depic- ted because of the incomplete structure of the attractor when m is small. When m is large, prediction indicators can vanish because of the scarcity of phase points in phase space. A method for overcoming the cut-off effect （m 〉 4） is proposed. Third, for heavy rains, precipitable water is more sensitive to the prediction validity period than temperat- ure or geopotential height; however, for hurricanes, geopotential height is most sensitive, followed by precipitable water.

关键词： extended range forecasting random error initial error model parameter error sensitivity

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Determination of hydraulic conductivity of fractured rock masses:A case study for a rock cavern project in Singapore

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Journal of Rock Mechanics and Geotechnical Engineering 2015年第2期7卷 178-184页

作者： Zhipeng Xu zhiye Zhao jianping Sun Ming Lu School of Civil and Environmental Engineering Nanyang Technological University Thomson Line Division of Rail Group Land Transport Authority

In order to reduce the risk associated with water seepage in an underground rock cavern project inSingapore, a reliable hydro-geological model should be established based on the in situ investigationdata. The key challenging issue in the hydro-geological model building is how to integrate limitedgeological and hydro-geological data to determine the hydraulic conductivity of the fractured rockmasses. Based on the data obtained from different stages （feasibility investigation stage, constructionstage, and post-construction stage）, suitable models and methods are proposed to determine the hydraulicconductivities at different locations and depths, which will be used at other locations in thefuture. 2015 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. All rights reserved.

关键词： Rock caverns Hydraulic conductivity Fractured rock masses Seepage analysis

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The methane adsorption capacity reduction process of water-bearing shale samples and its influencing factors: one example of Silurian Longmaxi Formation shale from the Southern Sichuan Basin in China

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Journal of Earth Science 2020年

作者： zhiye Gao Shuling Xiong State Key Laboratory of Petroleum Resources and Prospecting， China University of Petroleum Unconventional Petroleum Research Institute， China University of Petroleum

Due to the existence of water content in shale reservoir， it is quite meaningful to clarify the effect of water content on the methane adsorption capacity （MAC） of shale. However， the role of spatial configuration relationship between organic matter （OM） and clay minerals in the MAC reduction process is still unclear. The Silurian Longmaxi Formation shale samples from the Southern Sichuan Basin in China were prepared at five relative humidity （RH） conditions （0%， 16%， 41%， 76%， 99%） and the methane adsorption experiments were conducted on these water-bearing shale samples to clarify the MAC reduction process considering the spatial configuration relationship between clay minerals and OM and establish the empirical model to fit the stages. Total organic carbon （TOC） content and mineral compositions were analyzed and the pore structures of these shale samples were characterized by field-emission scanning electron microscopy （FE-SEM）， N2 adsorption and high-pressure mercury intrusion porosimetry （HPMIP）. The results showed that the MAC reduction of clay minerals in OM occurred at different RH conditions from that of clay minerals outside OM. Furthermore， the amount of MAC reduction of shale samples prepared at the same RH condition was negatively related with clay content， which indicated the protection role of clay minerals for the MAC of water-bearing shale samples. The MAC reduction process was generally divided into three stages for siliceous and clayey shale samples. And the MAC of OM started to decline during stage （1） for calcareous shale sample mainly because water could enter OM pores more smoothly through hydrophobic pathway provided by carbonate minerals than through hydrophilic clay mineral pores. Overall， this study will contribute to improving the evaluation method of shale gas reserve.

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