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Green evaluation of microwave-assisted leaching process of high titanium slag on life cycle assessment 被引量:4
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作者 陈菓 陈晋 +1 位作者 彭金辉 万润东 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第S1期198-204,共7页
A greenness evaluation index and system of microwave-assisted leaching method were established.The effects of the life cycle assessment variables,such as the resource consumption,environment impact,cost,time and quali... A greenness evaluation index and system of microwave-assisted leaching method were established.The effects of the life cycle assessment variables,such as the resource consumption,environment impact,cost,time and quality,were investigated,and the concept of green degree was applied in the production of synthetic rutile.An analytic hierarchy process was utilized to assess matrix of greenness evaluation.The Gauss-Seidel iterative matrix method was employed to solve the assessment matrix and obtain the weights and membership functions of all evaluation indexes.A fuzzy decision-making method was applied to build the greenness evaluation model,and then the scores of green degree in microwave-assisted leaching process was obtained.The greenness evaluation model was applied to the life cycle assessment of the microwave-assisted leaching process.The results show that the microwave-assisted leaching process has advantages over the conventional ones,with respect to energy-consumption,processing time and environmental protection. 展开更多
关键词 life cycle assessment greenness evaluation microwave-assisted leaching high titanium slag
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Mass-Based Environmental Factor and Energy Assessment of Microwave-Assisted Synthesized Transition Metal Nanostructures
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作者 Victor J. Law 《American Journal of Analytical Chemistry》 CAS 2024年第6期201-218,共18页
This paper describes mass-based energy phase-space projection of microwave-assisted synthesis of transition metals (zinc oxide, palladium, silver, platinum, and gold) nanostructures. The projection uses process energy... This paper describes mass-based energy phase-space projection of microwave-assisted synthesis of transition metals (zinc oxide, palladium, silver, platinum, and gold) nanostructures. The projection uses process energy budget (measured in kJ) on the horizontal axes and process density (measured in kJg−1) on the vertical axes. These two axes allow both mass usage efficiency (Environmental-Factor) and energy efficiency to be evaluated for a range of microwave applicator and metal synthesis. The metrics are allied to the: second, sixth and eleventh principle of the twelve principle of Green Chemistry. This analytical approach to microwave synthesis (widely considered as a useful Green Chemistry energy source) allows a quantified dynamic environmental quotient to be given to renewable plant-based biomass associated with the reduction of the metal precursors. Thus allowing a degree of quantification of claimed “eco-friendly” and “sustainable” synthesis with regard to waste production and energy usage. 展开更多
关键词 microwave-assisted Synthesis Transition Metals Nanostructures Allometry Scaling Power-Law Signature Green Chemistry
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Microwave-assisted Synthesis of Al_(4)SiC_(4) and Its Effect on Properties of MgO-C Refractories
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作者 WANG Li LIU Shijie +7 位作者 WEI Haoyu GUO Yanyan GENG Shangrui YAN Miaoxin QIN Feng GUO Yusen Ma Juanjuan DONG Binbin 《China's Refractories》 CAS 2024年第1期14-17,共4页
Al_(4)SiC_(4) was synthesized from Al powder, silicon carbide, and graphite by microwave sintering, and characterized by XRD and SEM. Then the synthesized material was added to the magnesia carbon refractory brick to ... Al_(4)SiC_(4) was synthesized from Al powder, silicon carbide, and graphite by microwave sintering, and characterized by XRD and SEM. Then the synthesized material was added to the magnesia carbon refractory brick to study its effect on the oxidation resistance, apparent porosity, bulk density, elastic modulus, and modulus of rupture. It is found that Al_(4)SiC_(4) can be synthesized by microwave sintering at 1 300 ℃ and the addition of Al_(4)SiC_(4)-containing material as an antioxidant can enhance the oxidation resistance of the magnesia carbon refractory brick. 展开更多
关键词 microwave-assisted synthesis Al_(4)SiC_(4) MgO-C refractories oxidation resistance
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Dendritic spine degeneration:a primary mechanism in the aging process
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作者 Gonzalo Flores Leonardo Aguilar-Hernández +3 位作者 Fernado García-Dolores Humberto Nicolini Andrea Judith Vázquez-Hernández Hiram Tendilla-Beltrán 《Neural Regeneration Research》 SCIE CAS 2025年第6期1696-1698,共3页
Recent reports suggest that aging is not solely a physiological process in living beings;instead, it should be considered a pathological process or disease(Amorim et al., 2022). Consequently, this process involves a w... Recent reports suggest that aging is not solely a physiological process in living beings;instead, it should be considered a pathological process or disease(Amorim et al., 2022). Consequently, this process involves a wide range of factors, spanning from genetic to environmental factors, and even includes the gut microbiome(GM)(Mayer et al., 2022). All these processes coincide at some point in the inflammatory process, oxidative stress, and apoptosis, at different degrees in various organs and systems that constitute a living organism(Mayer et al., 2022;AguilarHernández et al., 2023). 展开更多
关键词 AGING process STRESS
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Prediction and optimization of flue pressure in sintering process based on SHAP
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作者 Mingyu Wang Jue Tang +2 位作者 Mansheng Chu Quan Shi Zhen Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期346-359,共14页
Sinter is the core raw material for blast furnaces.Flue pressure,which is an important state parameter,affects sinter quality.In this paper,flue pressure prediction and optimization were studied based on the shapley a... Sinter is the core raw material for blast furnaces.Flue pressure,which is an important state parameter,affects sinter quality.In this paper,flue pressure prediction and optimization were studied based on the shapley additive explanation(SHAP)to predict the flue pressure and take targeted adjustment measures.First,the sintering process data were collected and processed.A flue pressure prediction model was then constructed after comparing different feature selection methods and model algorithms using SHAP+extremely random-ized trees(ET).The prediction accuracy of the model within the error range of±0.25 kPa was 92.63%.SHAP analysis was employed to improve the interpretability of the prediction model.The effects of various sintering operation parameters on flue pressure,the relation-ship between the numerical range of key operation parameters and flue pressure,the effect of operation parameter combinations on flue pressure,and the prediction process of the flue pressure prediction model on a single sample were analyzed.A flue pressure optimization module was also constructed and analyzed when the prediction satisfied the judgment conditions.The operating parameter combination was then pushed.The flue pressure was increased by 5.87%during the verification process,achieving a good optimization effect. 展开更多
关键词 sintering process flue pressure shapley additive explanation PREDICTION OPTIMIZATION
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Microwave-Assisted Facile and Rapid Esterification of Amino Acids I: Esterification of L-Leucine from Batch to Flow Processes and Scale-Up
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作者 Ritsuko Nagahata Takashi Nakamura +1 位作者 Yukie Mori Kazuhiko Takeuchi 《Natural Science》 2017年第4期110-122,共13页
We herein report our studies into the effects of microwave irradiation on the solvent-free esterification of L-leucine with alcohols. In the absence of solvent, microwave irradiation accelerated the reaction compared ... We herein report our studies into the effects of microwave irradiation on the solvent-free esterification of L-leucine with alcohols. In the absence of solvent, microwave irradiation accelerated the reaction compared to conventional oil bath heating. Measurement of the dielectric properties under the reaction conditions revealed that the high dielectric loss factor of the reaction mixture containing L-leucine, n-butanol, and a p-toluene sulfonic acid catalyst could be attributed to the acceleration of the reaction. The depth of microwave penetration into the reaction mixture as derived from the in-situ measurement of the dielectric properties was ~13 mm, which suggested that a thinner reaction vessel was favorable for the esterification of L-leucine. In addition to the batch reaction using a desktop microwave reactor, two types of flow reaction were also performed using a desktop tubular reactor and a semi-bench-scale tubular reactor. These flow reactions also exhibited high performances, thus allowing the scale-up of this reaction system for industrial use. 展开更多
关键词 microwave-assisted ESTERIFICATION Microwave Flow Reactor Dielectric Properties Amino Acid ESTER L-LEUCINE
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An Unprecedented Efficiency with Approaching 21%Enabled by Additive‑Assisted Layer‑by‑Layer Processing in Organic Solar Cells
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作者 Shuai Xu Youdi Zhang +6 位作者 Yanna Sun Pei Cheng Zhaoyang Yao Ning Li Long Ye Lijian Zuo Ke Gao 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期372-375,共4页
Recently published in Joule,Feng Liu and colleagues from Shanghai Jiaotong University reported a record-breaking 20.8%power conversion efficiency in organic solar cells(OSCs)with an interpenetrating fibril network act... Recently published in Joule,Feng Liu and colleagues from Shanghai Jiaotong University reported a record-breaking 20.8%power conversion efficiency in organic solar cells(OSCs)with an interpenetrating fibril network active layer morphology,featuring a bulk p-in structure and proper vertical segregation achieved through additive-assisted layer-by-layer deposition.This optimized hierarchical gradient fibrillar morphology and optical management synergistically facilitates exciton diffusion,reduces recombination losses,and enhances light capture capability.This approach not only offers a solution to achieving high-efficiency devices but also demonstrates the potential for commercial applications of OSCs. 展开更多
关键词 Organic solar cells Additive-assisted layer-by-layer processing Three-dimensional fibril morphology Bulk p-i-n structure Optical management
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Optimization of Microwave-assisted Extraction Technology of Polyphenols from Loropetalum chinense(R. Br.) Oliv 被引量:1
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作者 刘秀 黄维 +6 位作者 肖珑 陈靖宇 荣蓉 李瑾 唐彩红 谢鹏 金晨钟 《Agricultural Science & Technology》 CAS 2016年第11期2629-2635,共7页
In order to optimize the microwave-assisted extraction technology of polyphenols from Loropetalum chinense (R. Br.) Oliv., the effects of microwave power, ethanol concentration, solid to liquid ratio and extraction ... In order to optimize the microwave-assisted extraction technology of polyphenols from Loropetalum chinense (R. Br.) Oliv., the effects of microwave power, ethanol concentration, solid to liquid ratio and extraction time on polyphenols extraction rate were investigated. On the basis of single-factor test, a four-factor and three-level orthogonal test was designed by response surface method to establish a mathematical model between the response value and various factors. The results showed that the intensity of effect of different influencing factor on polyphenols ex- traction rate ranked as microwave power's〉solid to liquid ratio's〉extraction time's〉 ethanol concentration's. The optimum microwave-assisted extraction conditions for polyphenols from L. chinense were as follows: extraction power 254 W, ethanol concentration 60%, extraction time 12.5 rain and solid to liquid ratio 1:17. Under the optimum extraction conditions, the extraction rate of polyphenols from L. chinense was 19.17%. 展开更多
关键词 Loropetalum chinense (R. Br.) Oily. Potyphenols microwave-assisted extraction technology Response surface analysis
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Process Simulate软件在自动化生产线安装调试课程中的应用
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作者 骆峰 杨帆 +1 位作者 胡菡 李智 《工业控制计算机》 2024年第12期37-38,41,共3页
针对自动化生产线安装调试课程的实践教学难题提出了使用仿真软件进行虚拟装调的方案。介绍了如何使用Process Simulate软件对自动化生产线进行虚拟装调。实践证明,使用Process Simulate软件能够有效提高自动化生产线安装调试课程的实... 针对自动化生产线安装调试课程的实践教学难题提出了使用仿真软件进行虚拟装调的方案。介绍了如何使用Process Simulate软件对自动化生产线进行虚拟装调。实践证明,使用Process Simulate软件能够有效提高自动化生产线安装调试课程的实践教学效果。 展开更多
关键词 process Simulate软件 自动化生产线 虚拟装调
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基于Arduino与Processing的心率检测计设计研究 被引量:1
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作者 臧红波 华拓 管志岳 《家电维修》 2024年第3期74-76,共3页
随着社会经济的高速发展,人们的物质生活也有了极大的提高,但同时也伴随着各种疾病的到来,身体健康已经成为人们普遍关注的焦点,因此,心率检测仪、血压计、血糖仪等各种家用医疗监测仪器已经逐渐融入日常生活。心脏病是人们难以预防的... 随着社会经济的高速发展,人们的物质生活也有了极大的提高,但同时也伴随着各种疾病的到来,身体健康已经成为人们普遍关注的焦点,因此,心率检测仪、血压计、血糖仪等各种家用医疗监测仪器已经逐渐融入日常生活。心脏病是人们难以预防的突发致命疾病之一,本文介绍的是一款基于Arduino【是基于易用硬件和软件的原型开源平台,包由可编程的电路板(简称微控制器),以及集成开发环境(称为Arduino IDE)的现成软件组成】Processing(开源编程语言,包括编辑器、编译器、展示器)的简易心率检测计系统,其功能实用、操作简单,可以测量心率,当超出正常心率范围时及时预警,是一款便携的实时心率测试仪。 展开更多
关键词 Arduino processing 心率检测计 设计研究
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MICROWAVE-ASSISTED EXTRACTION OF GLYCYRRHIZIC ACID FROM LICORICE ROOT-EFFECT OF THE PROPERTY OF SOLUTION ON EXTRACTION OF GA 被引量:53
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作者 Pan Xuejun and Liu Huizhou (Young Scienctist Laboratory of Separation Science & Engineering, State Key Laboratory of Biochemical Engineering, Instigate of Chemical Metallurgy, Chinese Academy of Sciepces, Beijing 100080) 《化工学报》 EI CAS CSCD 北大核心 2000年第S1期240-243,共4页
The property of extraction solution is an important factor influencing the extraction efficiency. In the present work, the effect of the property of solution on extraction of GA was studied, which including the concen... The property of extraction solution is an important factor influencing the extraction efficiency. In the present work, the effect of the property of solution on extraction of GA was studied, which including the concentration of ethanol, ammonia and cation (M+), pH of extraction solution, different kinds of organic solvent etc. The results show that 50%-60%(v/v) ethanol can reach high percentage extraction of GA. If 1% (v/v) ammonia solution was added into 60%(v/v) ethanol, the percentage extraction can be increased from 2.0% to 2.31%. Without ammonia, 50mmol/L [M+] (M+ = K+, NH4+) was added into 60%(v/v) ethanol, percentage extraction of GA can reach about 2.26%. If pH of solution (60% ethanol) was adjust to pH=4.0, it can reach high percentage extraction. If pH of solution (60% ethanol + 50mmol [M+], pH=6.1) was adjust tO PH=4.0, especially M+ is K+ or NH4+, it can reach almost same extraction efficiency as that of 1% ammonia solution + 60% ethanol, and the operation environment can be greatly improved. 展开更多
关键词 glycyrrhizic acid licorice root microwave-assisted EXTRACTION
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Microwave-assisted extraction of polysaccharides from solanum nigrum 被引量:10
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作者 陈晓青 刘覃 +1 位作者 蒋新宇 曾帆 《Journal of Central South University of Technology》 EI 2005年第5期556-560,共5页
The microwave-assisted method was used to extract polysaccharides from solanum nigrum. The optimum experimental parameters, mechanism of the extraction and the effect of microwave-assisted extraction process on the st... The microwave-assisted method was used to extract polysaccharides from solanum nigrum. The optimum experimental parameters, mechanism of the extraction and the effect of microwave-assisted extraction process on the structures of polysaccharides were investigated. The extract was analyzed by the modified phenol-sulfuric acid method at 490nm. The optimum experimental parameters were obtained by orthogonal experiments as follows: extraction time 15min, microwave radiation power 455W and the process ratio of materials mass to solvent volume 1∶20. The results show that compared with the conventional reflux extraction, the microwave-assisted extraction has a higher yield in shorter time, with no effect on the finally obtained polysaccharides as seen from the FT-IR spectra. The scanning electron microscopy images reveal that the mechanism of the extraction is related to the structural changes of the plant cells in different extracting conditions. 展开更多
关键词 solanum nigrum POLYSACCHARIDES STRUCTURE microwave-assisted extraction
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Microwave-assisted Extraction of Isoflavones from Belamcanda chinensis 被引量:6
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作者 龚盛昭 程江 杨卓如 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第4期556-559,共4页
Microwave-assisted extraction (MAE) of isoflavones from Belamcanda chinensis was studied using ethanol as the solvent. The single factor experiment and the orthogonal method were used to optimize the MAE condition. ... Microwave-assisted extraction (MAE) of isoflavones from Belamcanda chinensis was studied using ethanol as the solvent. The single factor experiment and the orthogonal method were used to optimize the MAE condition. It was concluded that two doses of intermittent microwave power radiation, 300 W each for 4 rain, were needed for extraction. The mass ratio of solvent to material was 8:1 and the alcohol mass fraction was 80%. The extracted liquor was then concentrated under vacuum and degreased with petroleum ether. The yield of total isofiavones was about 8.8% and the contents of tectoridin and iridin were 67.6% and 16.3% respectively. Compared with direct-heating extraction (DHE), MAE may shorten extracting duration, reduce solvent consumption, and improve yield and purity of isoflavones from Belamcanda chinensis. 展开更多
关键词 Belamcanda chinensis ISOFLAVONE microwave-assisted extraction TECTORIDIN iridin
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Low temperature microwave-assisted vs conventional pyrolysis of various biomass feedstocks 被引量:7
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作者 Peter Shuttleworth Vitaliy Budarin +2 位作者 Mark Gronnow James H.Clark Rafael Luque 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2012年第3期270-274,共5页
A comparison between conventional pyrolysis and a novel developed low-temperature microwave-assisted pyrolysis methodology has been performed for the valorisation of a range of biomass feedstocks including waste resid... A comparison between conventional pyrolysis and a novel developed low-temperature microwave-assisted pyrolysis methodology has been performed for the valorisation of a range of biomass feedstocks including waste residues. Microwave pyrolysis was found to efficiently deliver comparable evolution of bio-gases in the system as compared with conventional pyrolysis at significantly reduced temperatures (120-180 ℃vs 250-400 ℃). The gas obtained from microwave-assisted pyrolysis was found to contain CO2, CH4 and CO as major components as well 展开更多
关键词 microwave-assisted pyrolysis biomass valorisation gas production
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Microwave-assisted Extraction of Effective Compounds from Traditional Chinese Herbal Medicine Ciwujia 被引量:4
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作者 王娟 沈平孃 沈永嘉 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第2期231-233,共3页
Microwave-assisted extraction (MAE) for active ingredients in Ciwujia was studied by using ethanol as the extractant. Comparing MAE with conventional methods, the former can save the extracting time and increase the c... Microwave-assisted extraction (MAE) for active ingredients in Ciwujia was studied by using ethanol as the extractant. Comparing MAE with conventional methods, the former can save the extracting time and increase the content of the active ingredients in product. As to the operation in MAE, the continuous radiation process is more convenient for the extraction for traditional Chinese medicine than the intermittent radiation process. Optimized by uniform design, MAE was proved to be an effective and novel process for extracting active ingredients in Ciwujia. The optimized MAE conditions are as follows: the microwave power is 510W, the radiation time 30min, the alcohol concentration at 80%, the ratio of solvent to solid material being 5:1, the soaking time 0.5h, and the herbal particle size is (520±19)μm. 展开更多
关键词 microwave-assisted extraction Ciwujia uniform design SAPONINS ISOFRAXIDIN
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Effect of microwave-assisted acidification on the microstructure of coal:XRD,^(1)H-NMR, and SEM studies 被引量:4
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作者 He Li Wuche Liu +5 位作者 Jiexin Lu Yi Lu Shiliang Shi Zheng Wang Qing Ye Zhenzhen Jia 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2023年第7期919-926,共8页
Microwave heating contributes to coal fracturing and gas desorption. However, problems of low penetration depth, local overheating and fracture closure exist. Coal demineralisation by acids has advantages in coal unbl... Microwave heating contributes to coal fracturing and gas desorption. However, problems of low penetration depth, local overheating and fracture closure exist. Coal demineralisation by acids has advantages in coal unblocking and permeability improvement, while it is difficult for acid to enter microcracks.Microwave-asisted acidification may offer an alternative. In this work, XRD,^(1)H-NMR, and SEM were used to evaluate the effect of microwave-assisted acidification on the microstructure of coal. Results show that kaolinite, calcite, and dolomite can be dissolved by acid. After microwave irradiation, the graphitization of microcrystalline structure of carbon improves. Microwave-assisted acidification erodes minerals in coal and enhances the graphitization degree of microcrystalline structure. Compared to individual microwave irradiation or acidification, the pore volume and pore connectivity can be greatly enhanced by microwave-assisted acidification. The NMR permeability of coal increased by 28.05%. This study demonstrates the potential of microwave-assisted acidification for coalbed methane recovery. 展开更多
关键词 microwave-assisted acidification MICROSTRUCTURE XRD ^(1)H-NMR SEM
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Microwave-assisted Extraction of Rutin and Quercetin from Flos Sophorae 被引量:6
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作者 LIMin-jing YOUJing-yan YAOShuang DINGLan LIUZhong-ying ZHANGHan-qi 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第6期703-706,共4页
Three microwave-assisted extraction(MAE) procedures were studied. The first procedure was household microwave oven dynamic extraction(HMODE). The second procedure was special microwave oven bath extraction(SMOBE). The... Three microwave-assisted extraction(MAE) procedures were studied. The first procedure was household microwave oven dynamic extraction(HMODE). The second procedure was special microwave oven bath extraction(SMOBE). The third procedure was microwave resonant cavity dynamic extraction(MRCDE). The results obtained by the three microwave-assisted extraction procedures were compared with those obtained by using traditional Soxhlet extraction. The results indicate that the MAE not only took a shorter time, but also simplified the procedure, and made the extraction a higher yield. At the same time the results obtained by the three MAE procedures were also compared with each other. 展开更多
关键词 microwave-assisted extraction(MAE) Flavonoid RUTIN QUERCETIN Flos Sophorae
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Optimization of microwave-assisted extraction of bioactive alkaloids from lotus plumule using response surface methodology 被引量:4
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作者 Wei Xiong Xianqiang Chen +3 位作者 Guangping Lv Dejun Hu Jing Zhao Shaoping Li 《Journal of Pharmaceutical Analysis》 CAS 2016年第6期382-388,共7页
In this work,a fast and efficient microwave-assisted extraction(MAE) method was developed to extract main bioactive alkaloids from lotus plumue.To optimize MAE conditions,three main factors were selected using univari... In this work,a fast and efficient microwave-assisted extraction(MAE) method was developed to extract main bioactive alkaloids from lotus plumue.To optimize MAE conditions,three main factors were selected using univariate approach experiments,and then central composite design(CCD).The optimal extraction conditions were as follows:methanol concentration of 65%,microwave power of 200 W,and extraction time of 260 s.A high performance liquid chromatography–diode array detector(HPLC–DAD) method was established to quantitatively analyze these phytochemicals in different lotus plumule samples and in different part of lotus.Chromatographic separation was carried out on an Agilent Zorbax Extend-C_(18) column(4.6 mm×150 mm,3.5 μm).Gradient elution was applied with the mobile phase constituted with 0.1% triethylamine in water(A)and acetonitrile(B):40%-70% B at 0-8 min,70%-100% B at 8–9 min,100% B for 2 min,and then equilibrated with 40% B for 2 min. 展开更多
关键词 LOTUS plumule FUNCTIONAL FOOD microwave-assisted EXTRACTION ALKALOIDS
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Microwave-assisted Micellar Extraction and Determination of Glycyrrhizic Acid and Liquiritin in Licorice Root by HPLC 被引量:4
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作者 孙晨 谢渝春 刘会洲 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第4期474-477,共4页
The feasibility of emploving non-ionic surfactant (Triton X-100) as an alternative and effective solventfor the microwave-assisted extraction of glycyrrhizic acid (GA) and liquiritin (LQ) from licorice root was ... The feasibility of emploving non-ionic surfactant (Triton X-100) as an alternative and effective solventfor the microwave-assisted extraction of glycyrrhizic acid (GA) and liquiritin (LQ) from licorice root was studied.The optimal extraction parameters based on the microwave-assisted micellar extraction technique were determined.Under the optimal conditions, i.e. 5% (by volume) Triton X-100, microwave-assisted extraction for 3--5min at 373K, the percentage extraction of active ingredients reached the highest value. The preconcentration tactor for GA and L'Q (about 13.5) and the extraction efficiency for these two ingredients approached 100% showed the coupling of microwave-assisted extraction and cloud-point extraction could be employed as a new and. effective techniquefor the rapid extraction and preconcentration of pharrnacologically active ingredients from medicinal plants SUCh aslicorice root without disturbing chromatographic analysis. 展开更多
关键词 microwave-assisted micellarextraction cloud-point extraction Triton X-100 glycyrrhizic acid LIQUIRITIN
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Microwave-assisted solvent extraction of castor oil from castor seeds 被引量:4
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作者 Nur Atirah Ibrahim Muhammad Abbas Ahmad Zaini 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第12期2516-2522,共7页
This study was aimed at evaluating the physicochemical properties and oxidation stability of castor oil using microwave-assisted solvent extraction(MAE). MAE was performed using 5% ethanol in hexane as solvent at diff... This study was aimed at evaluating the physicochemical properties and oxidation stability of castor oil using microwave-assisted solvent extraction(MAE). MAE was performed using 5% ethanol in hexane as solvent at different extraction times, power intensities and solvent-to-feed(S/F, ml of solvent to gram of feed) ratios.The process parameters were optimized by statistical approach using historical data design of response surface method(RSM). The oils were characterized for yield, physicochemical properties, dielectric properties and oxidation stability, and comparison was also made with oil extracted using Soxhlet method. Results show that the maximum oil yield of 37% was obtained at 20 min with microwave power intensity of 330 W and S/F ratio of 20. The main fatty acid composition of castor oil is ricinoleic acid. The density, refractive index, dielectric properties and oxidation stability of oils are not affected by the extraction methods and extraction parameters of MAE. However, the MAE-extracted oil is more viscous compared to that by Soxhlet method. With extra caution on oil oxidation, MAE could be a promising solvent extraction method with an 86% less in processing time and a higher yield. 展开更多
关键词 CASTOR SEED CASTOR oil DIELECTRIC properties microwave-assisted SOLVENT extraction OXIDATION stability
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