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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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Dynamic phase-mining optimization in open-pit metal mines

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Transactions of Nonferrous Metals Society of China 2010年第10期20卷 1974-1980页

作者：顾晓薇王青葛舒 college of resource and Civil Engineering Northeastern University

Three important aspects of phase-mining must be optimized:the number of phases,the geometry and location of each phase-pit(including the ultimate pit),and the ore and waste quantities to be mined in each phase.A model is presented,in which a sequence of geologically optimum pits is first generated and then dynamically evaluated to simultaneously optimize the above three aspects,with the objective of maximizing the overall net present *** this model,the dynamic nature of the problem is fully taken into account with respect to both time and space,and is robust in accommodating different pit wall slopes and different bench *** model is applied to a large deposit consisting of 2044 224 blocks and proved to be both efficient and practical.

关键词： open-pit phase-mining dynamic programming optimization

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Preparation of homogeneous ZnO nanoparticles via precipitation-pyrolysis with Zn_5(CO_3)_2(OH)_6 as precursor

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中国有色金属学会会刊：英文版 2006年第5期16卷 1205-1212页

作者：韩跃新丁亚卓印万忠马正先 college of resource and Civil Engineering Northeastern University

ZnO nanoparticles were synthesized via precipitation-pyrolysis (P&P), where the precursor zinc hydroxide carbonate (Zn5(CO3)2(OH)6) was obtained and then pyrolyzed. The results of TEM indicate that pyrolysis temperature is the predominant factor for controlling mean sizes of nanoparticles, ranging from 8 nm to 80 nm. Increasing the pyrolysis temperature enhances the mean size. The results of XRD show that nanoparticles are all of crystalline zincite. The mean size observed by TEM is in agreement with that calculated from the specific surface area(SSA) and the crystalline size calculated from the XRD patterns, indicating that the primary particles are rather uniform in size and have single crystals. The growth behaviors of epitaxy along the C-axis are responsible for the morphology of ZnO changing from sphere to rod-like shape, and then to reticulation. Compared with other synthesis approaches, P&P can get fairly good product with a relatively low cost.

关键词： ZnO 纳米粒子沉淀-高温分解形态 Zn5(CO3)2(OH)6

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Plasma Modification of Activated Carbon Fibers for Adsorption of SO_2

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Plasma Science and Technology 2013年第10期15卷 1047-1052页

作者：车垚周家勇王祖武 college of resource and Environmental Science Wuhan University

Viscose-based activated carbon fibers （VACFs） were treated by a dielectric-barrier discharge plasma under the feed gas of N2. The surface functional groups of VACFs were modified to improve the adsorption and catalysis capacity for SO2. The surface properties of the untreated and plasma-treated VACFs were diagnosed by SEM, BET, FTIR, and XPS, and the adsorption capacities of VACFs for SO2 were also compared and discussed. The results show that after the plasma treatment, the external surface of VACFs was etched and became rougher, while the surface area and the total pore volume decreased. FTIR and XPS revealed that nitrogen atoms were introduced onto the VACFs surface and the distribution of functional groups on the VACFs surface was changed remarkably. The adsorption characteristic of SO2 indicates that the plasmatreated VACFs have better adsorption capacity than the original VACFs due to the nitrogen functional groups and new functional groups formed in modification, which is beneficial to the adsorption of SO2.

关键词： cold plasma surface modification activated carbon fibers adsorption SO2

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Modeling of acute cadmium toxicity in solution to barley root elongation using biotic ligand model theory

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Journal of Environmental Sciences 2016年第4期28卷 112-118页

作者： Xuedong Wang Mingyan Wu Jingxing Ma Xiaolin Chen Luo Hua The Key Lab of resource Environment and GIS College of Resource Environment and TourismCapital Normal University

Protons（H^＋）as well as different major and trace elements may inhibit cadmium（Cd）uptake in aquatic organisms and thus alleviate Cd ***,little is known about such interactions in soil *** this study,the independent effects of the cations calcium（Ca^2＋）,magnesium（Mg^2＋）,potassium（K^＋）,H^＋ and zinc（Zn^2＋）on Cd toxicity were investigated with 5-day long barley root elongation tests in nutrient *** tested concentrations of selected cations and trace metal ions were based on the ranges that occur naturally in soil pore *** toxicity of Cd decreased with increasing activity of Ca^2＋,Mg^2＋,H^＋and Zn^2＋,but not K^＋.Accordingly,conditional binding constants were obtained for the binding of Cd^2＋,Ca^2＋,Mg^2＋,H^＋,and Zn^2＋ with the binding ligand：log K（CdBL）5.19,logK（CaBL）2.87,logK（MgBL）2.98,logK（HBL）5.13 and logK（ZnBL）5.42,***,it was calculated that on average 29% of the biotic ligand sites needed to be occupied by Cd to induce a 50% decrease in root *** the estimated constants,a biotic ligand model was successfully developed to predict the Cd toxicity to barley root elongation as a function of solution *** feasibility and accuracy of its application for predicting Cd toxicity in soils were discussed.

关键词： Cadmium Biotic ligand model (BLM) Toxicity Barley

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Effects of cadium, zinc and lead on soil enzyme activities

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Journal of Environmental Sciences 2006年第6期18卷 1135-1141页

作者： YANG Zhi-xin LIU Shu-qing ZHENG Da-wei FENG Sheng-dong college of resource and Environment China Agricultural University Beijing 100094 China college of resource and Environment Agricultural University of Hebei Baoding 071001 China

Heavy metal （HM） is a major hazard to the soil-plant system. This study investigated the combined effects of cadium （Cd）, zinc （Zn） and lead （Pb） on activities of four enzymes in soil, including calatase, urease, invertase and alkalin phosphatase. HM content in tops of canola and four enzymes activities in soil were analyzed at two months after the metal additions to the soil. Pb was not significantly inhibitory than the other heavy metals for the four enzyme activities and was shown to have a protective role on calatase activity in the combined presence of Cd, Zn and Pb; whereas Cd significantly inhibited the four enzyme activities, and Zn only inhibited urease and calatase activities. The inhibiting effect of Cd and Zn on urease and calatase activities can be intensified significantly by the additions of Zn and Cd. There was a negative synergistic inhibitory effect of Cd and Zn on the two enzymes in the presence of Cd, Zn and Pb. The urease activity was inhibited more by the HM combinations than by the metals alone and reduced approximately 20%--40% of urease activity. The intertase and alkaline phosphatase activities significantly decreased only with the increase of Cd concentration in the soil. It was shown that urease was much more sensitive to HM than the other enzymes. There was a obvious negative correlation between the ionic impulsion of HM in soil, the ionic impulsion of HM in canola plants tops and urease activity. It is concluded that the soil urease activity may be a sensitive tool for assessing additive toxic combination effect on soil biochemical parameters.

关键词： multiple heavy metal pollution canola plants soil enzyme ionic impulsion

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Soil and water conservation practice effects on soil physicochemical properties and crop yield in Ethiopia:review and synthesis

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Ecological Processes 2022年第1期11卷 206-221页

作者： Endale Bekele Jiru Habtamu Temesgen Wegari college of Agriculture and Natural resource Dilla UniversityDillaEthiopia college of Agriculture and Natural resource Bonga UniversityBongaEthiopia

Background:Land degradation is an urgent agenda that requires great effort and resources to *** worsens soil components through disrupting ecological functions and threatens agriculture *** overcome it,different soil and water conservation(SWC)practices have been undertaken in numerous parts of *** paper aims to review the effects of SWC practices on soil physicochemical properties and crop *** were collected from secondary sources via a computer library using various databases based on developed *** collected data were organized,categorized,and analyzed through descriptive *** mean difference of selected soil physicochemical properties obtained from treated and untreated farmland was tested using paired *** influencing crop yield on treated farmland were determined by a multiple linear regression ***:SWC practices influenced the soil physicochemical properties and crop yield either positively or *** mean values of available phosphorus(10.6 ppm,8.7 ppm),total nitrogen(0.5%,0.4%),soil pH(6.0%,5.8%),soil organic matter(4.4%,3.8%),and soil organic carbon(2.2%,1.8%)were on treated and untreated farmland under physical SWC practices,***,the mean values of these variables were higher on treated farmland than untreated farmland under both biological and integrated SWC *** mean value of bulk density was higher on untreated farmland than treated one and statistically significant under all SWC *** juu and stone-faced soil bund constantly increased crop yield,whereas soil bund and stone bund did ***:Proper implementation of SWC technologies through integrating physical and biological measures will boost the effectiveness of the practice in restoring soil physicochemical properties and improving crop ***,government due attention paid for land resources management in Ethiopia,whereby the annual SWC and tree planting campaign und

关键词： Land degradation Soil and water conservation Crop yield Soil physicochemical properties

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3-D numerical investigation of the wall-bounded concentric annulus flow around a cylindrical body with a special array of cylinders

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Journal of Hydrodynamics 2015年第1期27卷 120-130页

作者：张雪兰孙西欢李永业 college of Water resource and Engineering Taiyuan University of Technology Shanxi Conservancy Technical college

Concentric annulus flow around a combinational cylindrical body with a special array of cylinders at five high Reynolds numbers is investigated numerically using Fluent 6.3.26 in this paper. The numerical results show a good agreement with the experimental data in regard to the axial velocity of the flow. This study focuses on the flow structure and the hydrodynamic characteristics based on the velocity distribution, the pressure distribution, streamlines and vectors under I-D, 2-D and 3-D condi- tions. Meanwhile, some global parameters including the pressure coefficient, the drag coefficient and the lift coefficient are analyzed. Numerical results show that the high velocity region and the reverse wake zone with low velocity exist in some spaces due to the disturbance of the cylindrical body. Negative pressures appear in some regions. Neither a wide area vortex nor the vortex shedding appears in the wall-bounded domain. The drag along the axial direction is the main force acting on the cylindrical body in the pipe domain. The annulus flow around the cylindrical body is analyzed to reveal the hydrodynamic characteristics of the complex turbule- nt concentric annulus flow field due to the multi-effects in the pipeline.

关键词： numerical simulation concentric annulus high Reynolds number cylindrical body hydrodynamic characteristics

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Dynamics of Humic Substance-Complexed Copper and Copper Leaching During Composting of Chicken Manure

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Pedosphere 2010年第2期20卷 245-251页

作者： A.S.ALI college of resource and Environment Northwest A & F University

Chicken manure was composted for 110 d to evaluate changes in organic carbon (C) and humic substance-complexed copper (HS-Cu) extracted with water,sodium hydroxide (NaOH),and sodium pyrophosphate and sodium hydroxide mixture (Na 4 P 2 O 7-NaOH).The average HS-Cu content from the Na 4 P 2 O 7-NaOH extraction accounted for 46.8% of the total Cu in the compost,followed by those from the NaOH and water extractions,which accounted for 34.5% and 6% of the total Cu in the compost,***-Na 4 P 2 O 7-extractable HS-Cu increased throughout the composting ***-extractable HS-Cu increased during the first 50 d of composting and then leveled ***-extractable HS-Cu enhanced during the first 21 d and then ***-extractable HS-Cu was not correlated to NaOH-or NaOH-Na 4 P 2 O 7-extractable organic *** average amount of Cu leached from the compost was about 20% of the total Cu in the chicken manure and Cu leaching increased during the first 35 d of composting and then *** of Cu was significantly correlated to the concentrations of HS-Cu extracted with NaOH and water,but was not correlated to the concentration of HS-Cu extracted with NaOH-Na 4 P 2 O ***,NaOH-and water-extractable HS-Cu were relatively labile and NaOH-Na 4 P 2 O 7-extractable HS-Cu was relatively *** process after rapid decomposition could result in low potential of Cu leaching because of formation of more NaOH-Na 4 P 2 O 7-extractable HS-Cu.

关键词： humic substance leaching organic carbon

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Nest site selection of white-naped crane(Grus vipio) at Zhalong National Nature Reserve, Heilongjiang, China

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Journal of Forestry Research 2014年第4期25卷 947-952页

作者： Qing-ming WU Hong-fei ZOU Jian-zhang MA college of Wildlife resource Northeast Forestry University

White-naped crane （Grus vipio） is a globally threatened spe- cies. It is very important to analyze its nest site selection in circum- stances where there are multiple disturbances, and also helpful to accu- mulate valuable information about this threatened species and supply scientific suggestions for conservation and management. We studied nest site selection and the effects of environmental variables on nesting habits of white-naped crane at Zhalong National Nature Reserve, Qiqihar City, Heilongiiang, China, during March-May of 2002-2008. White-naped crane responded and adapted to changes in the quality of the spatial environments of landscape and microhabitat under multiple environ- mental disturbances. Nest site selection included two scales and two choices, namely the choice of nest site habitat type within the macro-habitat scale and nest site micro-habitat selection within the mi- cro-habitat scale. Nest sites were recorded only in reed marshes. The choice of nest site micro-habitat included three basic elements and six factors, namely incubation element （nest parameters factor, incubation temperature factor and incubation humidity factor）, safety element （pro- tection factor and concealment factor）, and food element （water factor）. Water, remnant reed clusters, and fire were major resource management challenges during the breeding period for the white-naped crane in this Reserve.

关键词： factor analysis environmental variable Grus vipio nestsite selection pattern Zhalong Nature Reserve

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