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Online identification and extraction method of regional large-scale adjustable load-aggregation characteristics
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作者 Siwei Li Liang Yue +1 位作者 Xiangyu Kong Chengshan Wang 《Global Energy Interconnection》 EI CSCD 2024年第3期313-323,共11页
This article introduces the concept of load aggregation,which involves a comprehensive analysis of loads to acquire their external characteristics for the purpose of modeling and analyzing power systems.The online ide... This article introduces the concept of load aggregation,which involves a comprehensive analysis of loads to acquire their external characteristics for the purpose of modeling and analyzing power systems.The online identification method is a computer-involved approach for data collection,processing,and system identification,commonly used for adaptive control and prediction.This paper proposes a method for dynamically aggregating large-scale adjustable loads to support high proportions of new energy integration,aiming to study the aggregation characteristics of regional large-scale adjustable loads using online identification techniques and feature extraction methods.The experiment selected 300 central air conditioners as the research subject and analyzed their regulation characteristics,economic efficiency,and comfort.The experimental results show that as the adjustment time of the air conditioner increases from 5 minutes to 35 minutes,the stable adjustment quantity during the adjustment period decreases from 28.46 to 3.57,indicating that air conditioning loads can be controlled over a long period and have better adjustment effects in the short term.Overall,the experimental results of this paper demonstrate that analyzing the aggregation characteristics of regional large-scale adjustable loads using online identification techniques and feature extraction algorithms is effective. 展开更多
关键词 Load aggregation Regional large-scale Online recognition Feature extraction method
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Adenosine cyclic phosphate with ultrasonic-assisted pectinase extraction alleviated allergic reactions in RBL-2H3 through inhibiting the influx of intracellular Ca^(2+) 被引量:1
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作者 Qiao Bai Xiaoping Feng +5 位作者 Yu Wang Chunyu Wu Ye Liu Jiao Sun Tianli Yue Fangyu Long 《Food Science and Human Wellness》 SCIE CSCD 2023年第3期832-841,共10页
Jujube contains abundant cyclic adenosine monophosphate(cAMP)and the ultrasonic-assisted pectinase extraction(UAPE)conditions for obtaining the maximum cAMP yield from jujube were optimized.Orthogonal array design was... Jujube contains abundant cyclic adenosine monophosphate(cAMP)and the ultrasonic-assisted pectinase extraction(UAPE)conditions for obtaining the maximum cAMP yield from jujube were optimized.Orthogonal array design was applied to evaluate the effects of 4 variables by UAPE on cAMP yield.The results showed that the optimal cAMP yield(783.0μg/g)was derived at ratio of liquid to solid 5 mL/g,ratio of pectinase to raw material 1.5%,time 60 min and temperature 40℃.Moreover,the effect of cAMP on the anti-allergic function of action induced by immunoglobulin E(IgE)and its meschanism was investigated through establishing the sensitized cell model in rat basophilic leukemia(RBL-2 H3)cells using dinitrophenylated(DNP)-bovine serum albumin(BSA)-IgE.The results showed that cAMP interfered with sensitized cells,effectively inhibited the occurrence of basophil degranulation in dose dependence,and significantly reduced the activity ofβ-hexosamindase(β-hex),at the optimal concentration of 50μg/mL.The level of anti-inflammatory factor interleukin-10(IL-10)was promoted and the content of pro-inflammatory factor tumor necrosis factor-α(TNF-α)was suppressed by cAMP.In addition,influx of intracellular Ca^(2+) was repressed effectively.Our results demonstrate that jujube cAMP regulated the cytokine balance in the allergy pathway through blocking the influx of extracellular Ca^(2+),with the prevention of allergy symptoms. 展开更多
关键词 ultrasonic-assisted pectinase extraction Cyclic adenosine monophosphate Rat basophilic leukemia cells Ca^(2+)influx Allergy
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DNA extraction of birch leaves by improved CTAB method and optimization of its ISSR system 被引量:10
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作者 PAN hua YANG Chuan-ping WEI Zhi-gang JIANG Jing 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第4期298-300,共3页
The basic method of DNA extraction (CTAB) was improved as the multi-times STE-CTAB extraction method and used to extract the DNA of birch leaved in this experiment. Results showed that the improved method is suitabl... The basic method of DNA extraction (CTAB) was improved as the multi-times STE-CTAB extraction method and used to extract the DNA of birch leaved in this experiment. Results showed that the improved method is suitable not only for genomic DNA extraction of birch but also for that of other plants. The purity of genornic DNA extracted by the.multi-times STE-CTAB extraction method is higher than that by one time STE-CTAB method, and it does not need the process of RNase. The factors of influencing ISSR system were explored based on the genomic DNA of birch extracted by the two methods. The optimal conditions for ISSR system were determined as follows: Mg2+ concentration is 1.5-3.0 mmol·L^-1, dNTP concentration 0.104).25 mmol·L^-1, the quantity of Taq polymerase 0.5-2.0 U, template DNA 30-100 ng, and the concentration of primer is 0.2-0.4 pmmol·L^-1, and the reaction program was as: initial denaturation for 5 min at 94℃, 30 cycles of denaturation for 30 s at 94℃,annealing for 30 s at 51℃, extension for 30 s at 72℃, and a final 7 min extension at 72℃. 展开更多
关键词 BIRCH DNA extraction method ISSR Reaction system
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CTAB-silica Method for DNA Extraction and Purification from Castanea mollissima and Ginkgo biloba 被引量:7
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作者 Shen Yongbao Shi Jisen 《Forestry Studies in China》 CAS 2003年第3期10-12,共3页
A new method CTAB-silica for DNA extraction and purification from the leaves and buds of Castanea mollissima and Ginkgo biloba was tested. The method is based on the silica-based purification protocol developed by Bo... A new method CTAB-silica for DNA extraction and purification from the leaves and buds of Castanea mollissima and Ginkgo biloba was tested. The method is based on the silica-based purification protocol developed by Boom et al. (1990). By modifying the protocol, plant genome DNA could be extracted easily from dormant buds, mature leaves, and other parts of plant. Our results showed that the purified DNA was of high purity and could be analyzed by PCR. Furthermore, this CTAB-silica method took much less time for a successful DNA purification process compared to the traditional methods (CTAB and SDS). By our method, the suitable DNA can be extracted and purified from over 10 plant samples by one person in an hour. 展开更多
关键词 DNA extraction and purification CTAB-silica method Castanea mollissima Ginkgo biloba
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Physicochemical properties and biological activities of polysaccharides from the peel of Dioscorea opposita Thunb.extracted by four different methods 被引量:6
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作者 Zuowei Zhao Li Wang +4 位作者 Yuan Ruan Chunnan Wen Menghuan Ge Yanyan Qian Bingji Ma 《Food Science and Human Wellness》 SCIE CSCD 2023年第1期130-139,共10页
Polysaccharides are the important biologically active components found in the peel of Dioscorea opposita Thunb.(DTTP).The influences of 4 extraction methods,namely hot water extraction(W),acidic extraction(HA),hot-com... Polysaccharides are the important biologically active components found in the peel of Dioscorea opposita Thunb.(DTTP).The influences of 4 extraction methods,namely hot water extraction(W),acidic extraction(HA),hot-compressed water extraction(HCW)and enzyme-assisted extraction(EAE),on the yields,physicochemical properties,hypoglycemic and antioxidant activities of polysaccharides from DTTP were studied and compared.Among these DTTP polysaccharides,DTTP-HA was outstanding in several respects.DTTP-HA was the most water soluble;it had the highest total carbohydrate content(85.08%),the highest uronic acid(13.20%)and the highest thermal stability.DTTP-HA and DTTP-W possessed a triple-helix structure.These 4 kinds of polysaccharides have the same types of monosaccharides,but in different molar percentages.Extraction method had a significant impact on the microstructures of the extracted polysaccharides.DTT-HA exhibited irregular structure with many holes.Among the 4 extracted methods,the DTTP-HA and DTTP-W initially exhibited higher hypoglycemic and antioxidant activities.The better bioactivities of DTTP-HA may be related to the above factors.The findings indicated that acid extraction is an effective method to extract polysaccharides with high biological activities from DTTP. 展开更多
关键词 Dioscorea opposita Thunb peel POLYSACCHARIDES Different extraction methods Physicochemical characteristics Biological activities
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Rib stability: A way forward for safe coal extraction in India 被引量:1
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作者 Singh Satyendra K. Agrawal Harshit Singh Awanindra P. 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第6期1087-1091,共5页
Ensuring rib stability during pillar extraction is of prime importance in bord and pillar(B&P) method of underground coal mining with caving. Rib stability has been assessed here by way of assessing factor of safe... Ensuring rib stability during pillar extraction is of prime importance in bord and pillar(B&P) method of underground coal mining with caving. Rib stability has been assessed here by way of assessing factor of safety(FOS), a ratio of the strength of rib to stress on it. Earlier formulations for rib stability when applied to case studies gave very low FOS value suggesting significant ground control problems, which were contrary to the field observations. This has necessitated the need to revisit the concept of rib stability. The stress coming on the rib is estimated with the use of numerical modeling technique using the FLAC^(3D) software. The methodology of assessing rib-stability with the help of suggested rib-strength formulation has been validated at eight Indian coal mines. The outcome of this study finds relevance and importance in ensuring underground coal liquidation with improved safety and conservation. 展开更多
关键词 RIB stress estimation Rib-strength Rib-stability Numerical modeling Bord & PILLAR method UNDERGROUND COAL extraction
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Peanut proteins:Extraction,modifications,and applications:A comprehensive review 被引量:1
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作者 Song Cui David Julian McClements +7 位作者 Xingfeng Xu Bo Jiao Liyang Zhou Hualu Zhou Liu Xiong Qiang Wang Qingjie Sun Lei Dai 《Grain & Oil Science and Technology》 CAS 2023年第3期135-147,共13页
As naturally sourced proteins,peanut proteins have garnered significant attention from the food industry,owing to their numerous advantages,such as easy extraction,non-pungency,and high bioavailability.Furthermore,pea... As naturally sourced proteins,peanut proteins have garnered significant attention from the food industry,owing to their numerous advantages,such as easy extraction,non-pungency,and high bioavailability.Furthermore,peanut proteins are highly digestible in the gastrointestinal tract and boast a high net protein utilization rate,making them an appealing protein source in food products and a promising alternative to animal protein.In this paper,the recent works on the extraction method,modification method,and application of peanut proteins were reviewed.Both advantages and disadvantages of current extraction and modification were discussed.Recently updated information about peanut protein research was summarized.Based on these,the prospection of peanut proteins research was presented,which may be instructive for future research in this field.Future research is still needed for accessible modification methods to develop the functional properties of peanut proteins. 展开更多
关键词 Peanut protein COMPOSITION extraction methods Modifications Applications Plant-based foods
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A comparison study on structure-function relationship of polysaccharides obtained from sea buckthorn berries using different methods:antioxidant and bile acid-binding capacity 被引量:9
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作者 Qiaoyun Li Zuman Dou +5 位作者 Qingfei Duan Chun Chen Ruihai Liu Yueming Jiang Bao Yang Xiong Fu 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期494-505,共12页
In this study,the structural characters,antioxidant activities and bile acid-binding ability of sea buckthorn polysaccharides(HRPs)obtained by the commonly used hot water(HRP-W),pressurized hot water(HRP-H),ultrasonic... In this study,the structural characters,antioxidant activities and bile acid-binding ability of sea buckthorn polysaccharides(HRPs)obtained by the commonly used hot water(HRP-W),pressurized hot water(HRP-H),ultrasonic(HRP-U),acid(HRP-C)and alkali(HRP-A)assisted extraction methods were investigated.The results demonstrated that extraction methods had significant effects on extraction yield,monosaccharide composition,molecular weight,particle size,triple-helical structure,and surface morphology of HRPs except for the major linkage bands.Thermogravimetric analysis showed that HRP-U with filamentous reticular microstructure exhibited better thermal stability.The HRP-A with the lowest molecular weight and highest arabinose content possessed the best antioxidant activities.Moreover,the rheological analysis indicated that HRPs with higher galacturonic acid content and molecular weight showed higher viscosity and stronger crosslinking network(HRP-C,HRP-W and HRP-U),which exhibited stronger bile acid binding capacity.The present findings provide scientific evidence in the preparation technology of sea buckthorn polysaccharides with good antioxidant and bile acid binding capacity which are related to the structure affected by the extraction methods. 展开更多
关键词 Sea buckthorn extraction method STRUCTURE Rheological properties Antioxidant activity Bile acid binding capacity
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Parameters of Exterior Ballistic Feature Points Extraction in Radar Measurement Data by EMD
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作者 Wanjun Zhang Kailin Wang +2 位作者 Xiaoying Wu Guohui Li Hongtian Liu 《Journal of Beijing Institute of Technology》 EI CAS 2018年第4期503-509,共7页
The problem of measuring exterior ballistic feature points is always difficult to solve and it is essentiale on exterior ballistic measurement.By analysis of radar reflection characteristics and non-stationary echo si... The problem of measuring exterior ballistic feature points is always difficult to solve and it is essentiale on exterior ballistic measurement.By analysis of radar reflection characteristics and non-stationary echo signals of exterior ballistic feature points,the echo data of exterior ballistic feature points is measured by using the continuous wave radar.The parameters of feature points are extracted by the empirical mode decomposition method(EMD)of Hilbert-Huang transform(HHT)spectrum analysis technique.The radar echo signal model and EMD extraction model are established to analyze the exterior ballistic mutation point detection and EMD extraction method of aliasing echo signal.Typical feature point parameters of exterior ballistic in rocket flight tests are carried out and the effectiveness of the method is verified.A new method of measuring the parameters of exterior ballistic feature point is therefore presented. 展开更多
关键词 exterior ballistic characteristic points empirical mode decomposition method(EMD) continuous wave radar information extraction
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Hybrid-PIC/PIC simulations on ion extraction by electric field in laser-induced plasma
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作者 Xiao-Yong Lu Cheng Yuan +1 位作者 Xiao-Zhang Zhang Zhi-Zhong Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第4期316-321,共6页
The processes of electric ion extraction from plasma induced by pulse lasers are simulated by particle-in-cell(PIC)method and hybrid-PIC method.A new calculation scheme named preprocessing hybrid-PIC is presented beca... The processes of electric ion extraction from plasma induced by pulse lasers are simulated by particle-in-cell(PIC)method and hybrid-PIC method.A new calculation scheme named preprocessing hybrid-PIC is presented because neither of the two methods above is omnipotent,especially under the circumstance of high initial plasma density.The new scheme provides credible results with less computational consumption than PIC method in both one-and two-dimensional simulations,except forΠ-type electrode configuration.The simulation results show that the M-type performs best in all electrode configurations in both high-density and low-density plasma conditions. 展开更多
关键词 ion extraction particle-in-cell(PIC)method hybrid-PIC ELECTRODE CONFIGURATION
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Analysis of Influence Factors for FCC Slurry Separation by Mixed Solvent Extraction
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作者 Sun Yudong Zhao Xiaoning +2 位作者 Liu Ziyuan Feng Yi Han Zhongxiang 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2022年第1期111-116,共6页
Daqing FCC slurry was treated using mixed solvent containing N,N-dimethylformamide(extraction solvent)and n-paraffin(stripping-agent).The influence of solvent formulation(ratio of DMF/stripping-agent),temperature,time... Daqing FCC slurry was treated using mixed solvent containing N,N-dimethylformamide(extraction solvent)and n-paraffin(stripping-agent).The influence of solvent formulation(ratio of DMF/stripping-agent),temperature,time and solvent-oil ratio on yield and aromatics content of the extract oil were analyzed by a four-factor and three-level orthogonal experimental design.The polynomial regression models between the extract oil yield and aromatics content with the four factors were established.Response surface analysis showed that solvent formulation,temperature and solvent-oil ratio have significant effects on extraction result and there is an interaction between temperature and solvent-oil ratio on aromatics content,when the FCC slurry is extracted by mixed solvent.However,the extraction time has no significant effect.The optimal conditions for FCC slurry extraction covered:a solvent mixed ratio of 2.3,a temperature of 62.8℃,a solvent-oil ratio of 3.2,and a time of 35 min.The result of verification experiment was in good agreement with the prediction of the model. 展开更多
关键词 solvent formulation FCC slurry extraction response surface method extract oil yield aromatics content
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Comparison of Three Methods in Extracting Coherent Modes from a Doppler Backscatter System
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作者 张小辉 刘阿娣 +7 位作者 周楚 胡健强 王明远 俞昌旋 刘万东 李弘 兰涛 谢锦林 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第12期92-95,共4页
We compare three different methods to extract coherent modes from Doppler backscattering (DBS), which are center of gravity (COG) of the complex amplitude spectrum, spectrum of DBS phase derivative (phase derivat... We compare three different methods to extract coherent modes from Doppler backscattering (DBS), which are center of gravity (COG) of the complex amplitude spectrum, spectrum of DBS phase derivative (phase derivative method), and phase spectrum, respectively. These three methods are all feasible to extract coherent modes, for example, geodesic acoustic mode oscillation. However, there are stilI differences between dealing with high frequency modes (several hundred kHz) and low frequency modes, (several kHz) hiding in DBS signal. There is a significant amount of power at low frequencies in the phase spectrum, which can be removed by using the phase derivative method and COG. High frequency modes are clearer by using the COO and the phase derivative method than the phase spectrum. The spectrum of DBS amplitude does not show the coherent modes detected by using COG, phase derivative method and phase spectrum. When two Doppler shifted peaks exist, coherent modes and their harmonics appear in the spectrum of DBS amplitude, which are introduced by the DBS phase. 展开更多
关键词 DBS Comparison of Three methods in extracting Coherent Modes from a Doppler Backscatter System COG Figure
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基于不同提取物中的花青素智能pH复合膜的研究进展
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作者 赵娅敏 张敏 +5 位作者 张沛春 张斌 齐燕姣 鲜亮 王文芳 陈丽华 《食品与发酵工业》 CAS 北大核心 2025年第1期373-380,共8页
食品包装是食物给人的第一印象,它可以引起或抑制人们的食欲,在提高食物的外观和质量方面发挥着极其重要的作用。如何更好地保护广大消费者免受变质腐烂的食品带来未知疾病的困扰,进一步提高食品质量已成为重要的研究方向。而花青素是... 食品包装是食物给人的第一印象,它可以引起或抑制人们的食欲,在提高食物的外观和质量方面发挥着极其重要的作用。如何更好地保护广大消费者免受变质腐烂的食品带来未知疾病的困扰,进一步提高食品质量已成为重要的研究方向。而花青素是重要的天然水溶性色素,广泛存在于植物中,其属于多酚家族的黄酮类物质,具有良好的pH敏感性。该文综述了近几年研究人员从不同植物中提取出花青素,将其作为指示剂制备智能pH复合膜,通过复合膜颜色的变化以监测肉类、牛奶和果蔬等的新鲜程度方面的最新研究进展,还讨论了花青素的来源、结构和性质,为研究人员探索从不同植物中提取的花青素智能pH指示膜在其他领域中的应用潜力提供一定的思路。 展开更多
关键词 花青素 提取方法 PH敏感性 应用
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不同提取方法对杏仁蛋白结构和功能特性的影响
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作者 李晶晶 罗婷婷 +5 位作者 胡海玥 耿东宇 刘雅萱 王丽娜 杨晨 汪建明 《食品工业科技》 北大核心 2025年第5期72-80,共9页
为提高杏仁蛋白(Almond protein,AP)的利用率,本研究使用等电点沉淀法(Alkaline extraction by isoelectric precipitation,AI)、热碱法(Thermal-alkaline,TA)和盐析法(Salt extraction,SE)提取AP,分别为AIAP、TAAP和SEAP,探究提取方法... 为提高杏仁蛋白(Almond protein,AP)的利用率,本研究使用等电点沉淀法(Alkaline extraction by isoelectric precipitation,AI)、热碱法(Thermal-alkaline,TA)和盐析法(Salt extraction,SE)提取AP,分别为AIAP、TAAP和SEAP,探究提取方法对蛋白质结构和功能特性的影响。结果表明,不同提取方法对AP的结构和功能特性具有显著影响。SEAP的提取率(55.94%)和纯度(88.21%)最高,AIAP的纯度最低(75.06%),TAAP的提取率最低(50.71%)。AIAP表面粗糙且结构疏松,而TAAP和SEAP的结构致密,AIAP的β-折叠含量(44.97%)和表面疏水性高于TAAP和SEAP。相较于TAAP和SEAP,AIAP的持水性和持油性较高。SEAP和TAAP的溶解度显著高于AIAP,且乳化特性和起泡特性较好。本研究为杏仁蛋白在食品工业的应用提供一定的理论参考。 展开更多
关键词 提取方法 杏仁蛋白 结构 功能特性
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水蒸气蒸馏提取肉桂精油工艺及成分的分析
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作者 刘婷 朱慧 +5 位作者 才让东珠 成述儒 罗志皓 易雪娇 张涛 陈欢 《中国粮油学报》 北大核心 2025年第1期149-155,共7页
为提高肉桂精油提取率,本实验选用水蒸气蒸馏法,首先通过单因素实验,研究分析4个因素(蒸馏时间、料液比、浸泡时间、料液中氯化钠的体积分数)对肉桂精油提取率的影响;然后利用响应面设计对肉桂精油提取工艺进行优化;最后借助气相色谱-... 为提高肉桂精油提取率,本实验选用水蒸气蒸馏法,首先通过单因素实验,研究分析4个因素(蒸馏时间、料液比、浸泡时间、料液中氯化钠的体积分数)对肉桂精油提取率的影响;然后利用响应面设计对肉桂精油提取工艺进行优化;最后借助气相色谱-质谱联用技术(GC-MS)对其成分、含量进行测定分析。结果表明:提取率的回归方程相关系数R 2=0.98,方程回归模型极显著(P<0.01),回归模型拟合性较好,肉桂精油最佳提取条件为:蒸馏时间3 h,料液比1∶13,浸泡时间40 min,氯化钠的体积分数3.6%,且在该条件下提取率约为3.30%;最佳工艺提取的肉桂精油共检测出75种成分,占总精油的87.32%,其主要成分为反式肉桂醛。 展开更多
关键词 肉桂精油 水蒸气蒸馏 提取率 响应面设计 成分分析
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超声辅助酶法提取咖啡果皮花青素工艺优化及其体外抗氧化活性评价
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作者 李学玲 李雪 +3 位作者 任四妹 许苑南 郭洁 杨莉 《中国酿造》 北大核心 2025年第2期251-255,共5页
为探究咖啡果皮花青素的提取工艺和体外抗氧化能力,该研究采用超声辅助酶法提取咖啡果皮花青素,通过单因素试验及正交试验对咖啡果皮花青素提取工艺进行优化,并研究其体外抗氧化活性。结果表明,咖啡果皮花青素最佳提取工艺条件为:提取温... 为探究咖啡果皮花青素的提取工艺和体外抗氧化能力,该研究采用超声辅助酶法提取咖啡果皮花青素,通过单因素试验及正交试验对咖啡果皮花青素提取工艺进行优化,并研究其体外抗氧化活性。结果表明,咖啡果皮花青素最佳提取工艺条件为:提取温度60℃、乙醇体积分数60%、果胶酶添加量2%、料液比1∶50(g∶mL)、提取时间40 min。在此优化条件下,咖啡果皮花青素得率达0.274%。体外抗氧化试验结果表明,当样品质量浓度为30μg/mL时,其对DPPH、OH自由基的清除率最佳,分别为91.40%、67.28%,半抑制浓度(IC50)值分别为6.36μg/mL、12.16μg/mL;当样品质量浓度为5μg/mL时,总还原能力最高(吸光度值为0.987)。因此,咖啡果皮花青素具有一定的抗氧化能力。 展开更多
关键词 咖啡果皮 花青素 超声辅助酶法 提取工艺 体外抗氧化活性
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Box-Behnken设计优化鸡腿堇菜总黄酮超声提取工艺及抗氧化活性研究
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作者 张桂娟 李大亮 +5 位作者 吕文博 徐丹鸿 李明涛 宋世杰 曹鑫桐 陈鑫 《食品与发酵科技》 2025年第1期80-87,共8页
考察超声提取温度、乙醇浓度、超声提取功率、料液比、超声提取时间5个因素对鸡腿堇菜总黄酮得率的影响,采用Box-Behnken响应面分析法优化超声波提取鸡腿堇菜总黄酮工艺,并通过DPPH自由基清除能力考察鸡腿堇菜总黄酮提取物的抗氧化活性... 考察超声提取温度、乙醇浓度、超声提取功率、料液比、超声提取时间5个因素对鸡腿堇菜总黄酮得率的影响,采用Box-Behnken响应面分析法优化超声波提取鸡腿堇菜总黄酮工艺,并通过DPPH自由基清除能力考察鸡腿堇菜总黄酮提取物的抗氧化活性。结果表明,鸡腿堇菜总黄酮提取最优工艺为:超声提取温度56℃、乙醇浓度48%、超声提取功率300 W、料液比1∶26 g/mL、超声提取时间60 min,在此条件下鸡腿堇菜总黄酮得率为(2.83±0.02)%,鸡腿堇菜总黄酮提取量为28.35 mg/g;抗氧化试验结果表明鸡腿堇菜总黄酮提取物清除DPPH自由基的IC50值为0.32 mg/mL,清除作用随着质量浓度的增大而升高,当质量浓度为6 mg/mL时清除率可达92.08%,表明鸡腿堇菜总黄酮提取物具有良好的抗氧化活性。研究结果为系统研究及开发鸡腿堇菜植物资源提供理论依据及技术参考。 展开更多
关键词 响应面法 鸡腿堇菜 总黄酮 提取工艺 抗氧化活性
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基于多源遥感数据的遥感影像生态地块划分方法
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作者 李双营 《现代电子技术》 北大核心 2025年第5期142-146,共5页
为资源合理利用、生态保护与修复提供科学依据,文中提出基于多源遥感数据的遥感影像生态地块划分方法,实现了高精度生态地块划分。采用高频调制融合法逐像素融合处理采集的生态环境多源遥感影像;构建新的卷积神经网络(CNN),以融合后的... 为资源合理利用、生态保护与修复提供科学依据,文中提出基于多源遥感数据的遥感影像生态地块划分方法,实现了高精度生态地块划分。采用高频调制融合法逐像素融合处理采集的生态环境多源遥感影像;构建新的卷积神经网络(CNN),以融合后的高光谱影像为输入,通过在CNN中引入分组卷积和残差学习,实现输入高光谱影像多尺度特征提取,经过全连接层和softmax层的处理后,输出生态地块划分结果,并在softmax层中引入多分类Focal loss损失函数,解决生态地块划分结果产生的类别不平衡问题,提升生态地块划分精度。实验证明,该方法能够准确划分生态地块,划分精度平均值达到95.38%。融合后的多源遥感影像光谱扭曲度数值均低于20,可以确保融合影像在光谱信息上的高保真度,提高生态地块划分的准确性。 展开更多
关键词 多源遥感 遥感影像 生态地块 划分方法 高通滤波融合 高光谱影像 融合影像 特征提取
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不同加工工艺对胡柚汁品质的影响研究 被引量:1
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作者 朱奕婷 林杨 +3 位作者 汪丽霞 徐小忠 林倩倩 陈诺 《食品与发酵工业》 CAS 北大核心 2025年第1期297-304,共8页
以常山胡柚为原料,研究胡柚果经过不同取汁方式、不同杀菌工艺等关键果汁加工单元操作前后的胡柚汁品质变化。通过对胡柚汁微生物、酶活、色度、黄酮等多个指标进行测定,分析不同加工工艺对胡柚汁品质的影响。研究表明,带皮取汁能较好... 以常山胡柚为原料,研究胡柚果经过不同取汁方式、不同杀菌工艺等关键果汁加工单元操作前后的胡柚汁品质变化。通过对胡柚汁微生物、酶活、色度、黄酮等多个指标进行测定,分析不同加工工艺对胡柚汁品质的影响。研究表明,带皮取汁能较好保留胡柚皮中总酚、黄酮及抗坏血酸成分,而对胡柚汁pH、可滴定酸和总糖含量无显著影响(P<0.05),可溶性固形物略有增加,果汁亮度下降、黏度上升;去皮去囊衣的胡柚汁营养损失较大,但具有更好的感官品质及总超氧化物歧化酶(superoxide dismutase,SOD)活力。热杀菌会降低胡柚汁中微生物数量、总SOD活力、酸度、可溶性固形物、黄酮及抗坏血酸含量,增加总糖和总酚含量,对果汁整体色度影响显著,且不同杀菌温度对各处理果汁品质的影响差异显著。二次杀菌几乎可以杀灭胡柚汁中所有微生物,但同时会降低总SOD活力、黄酮及抗坏血酸含量,与热杀菌相比,二次杀菌对胡柚汁品质的总体影响较小。 展开更多
关键词 常山胡柚 加工工艺 品质 取汁方式 热杀菌 二次杀菌
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响应面法优化蓝莓酒渣花青素酶法提取工艺 被引量:1
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作者 陈近秋 吉姆·哈迪 +1 位作者 李红雨 曾令文 《中国酿造》 北大核心 2025年第1期206-211,共6页
为了高质化利用蓝莓酒渣,以纤维素酶为对照,选择淀粉酶、果胶酶、酸性蛋白酶、中性蛋白酶为实验组,以无水乙醇为提取溶剂提取蓝莓酒渣中的花青素。采用单因素试验考察提取酶添加量、提取时间、提取温度以及初始pH值对花青素提取量的影响... 为了高质化利用蓝莓酒渣,以纤维素酶为对照,选择淀粉酶、果胶酶、酸性蛋白酶、中性蛋白酶为实验组,以无水乙醇为提取溶剂提取蓝莓酒渣中的花青素。采用单因素试验考察提取酶添加量、提取时间、提取温度以及初始pH值对花青素提取量的影响,并通过响应面试验优化蓝莓酒渣花青素酶法提取工艺。结果表明,酶法提取花青素的最佳工艺条件为淀粉酶添加量0.7%,蓝莓酒渣与无水乙醇料液比为1∶100(g∶m L),提取温度60℃,提取时间为40 min,初始pH值为5。在此优化条件下,花青素提取量为0.68 mg/g,比未优化前提高了20.8%。 展开更多
关键词 蓝莓酒渣 花青素 酶法提取 工艺优化 响应面法
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