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Extraction of Cinnamomum longepaniculatum deciduous leaves essential oil using solvent-free microwave extraction: Process optimization and quality evaluation
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作者 Chunlei Wei Chuyun Wan +1 位作者 Fenghong Huang Tingting Guo 《Oil Crop Science》 CSCD 2023年第1期7-15,共9页
The optimal process conditions for solvent-free microwave extraction(SFME)of essential oils from Cinnamomum longepaniculatum deciduous leaves after moisture conditioning were established by response surface methodolog... The optimal process conditions for solvent-free microwave extraction(SFME)of essential oils from Cinnamomum longepaniculatum deciduous leaves after moisture conditioning were established by response surface methodology(RSM).A Box-Behnken design(BBD)was applied to evaluate the effects of three independent variables:moisture content(A:54%–74%),microwave power(B:300–500 W)and microwave time(C:20–40 min),on the extraction yield of essential oil.The compounds of the essential oils obtained by SFME,hydro-distillation and microwaveassisted hydro-distillation(MADE)were identified by gas chromatography-mass spectrometry(GC-MS),and the total lipids of C.longepaniculatum fresh leaves and deciduous leaves were analyzed.The correlation analysis of the response regression model indicated that quadratic polynomial model could be employed to optimize the extraction of essential oil.The optimal extraction condition was A:58%,B:400 W and C:28 min.In the optimal condition,the maximum extraction yield was 4.475 mL/100 g dw and higher than that by MADE.The main compound of the essential oil was eucalyptol(63.54%),and total oxygenated compounds was 78.95%,mainly caused by SFME and the metabolism of endophytic bacteria with decreasing content of phospholipids and fatty acids.Analysis of variance under the extraction condition illustrated high fitness of the model and the success of RSM for optimizing and reflecting the expected process condition.SFME combined with moisture regulation was an effective method for extracting essential oil from C.longepaniculatum deciduous leaves. 展开更多
关键词 Cinnamomum longepaniculatum Deciduous leaves Solvent-free microwave extraction Response surface methodology extraction yield Essential oil
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Study on microwave-assisted extraction of coal 被引量:4
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作者 陈红 逯俊庆 +1 位作者 葛岭梅 李建伟 《Journal of Coal Science & Engineering(China)》 2007年第1期74-78,共5页
The effect of different factors on coal extraction yield-temperature, solvent, coal type and irradiation time were investigated for different China coals under microwave-assisted extraction(MAE). The results show th... The effect of different factors on coal extraction yield-temperature, solvent, coal type and irradiation time were investigated for different China coals under microwave-assisted extraction(MAE). The results show that the optimum temperature for ethanol, acetone and THF are 393,373 and 373 K respectively and the extraction yield of THF is higher than that of other two solvents under MAE. Extraction with several single organic solvents were conducted for the 5 typical China coals-Shenfu, Tongchuan, Panzhihua, Yitai and Huating coal under microwave-assisted extraction and Soxhlet extraction. Results indicat that extraction yield of ethylenediamine, ethanol, acetone, tetrahydrofuran under MAE are all higher than that of Soxhlet extraction and MAE required less time. Tongchuan coal extracts of ethanol and acetone which were extracted by MAE and Soxhlet extraction were analyzed by GC/MS. 展开更多
关键词 MAE COAL extraction yield GC/MS analysis
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A Comparative Study on Hemp(Cannabis sativa)Essential Oil Extraction Using Traditional and Advanced Techniques 被引量:1
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作者 Saima naz Muhammad Asif Hanif +1 位作者 Tariq Mahmood Ansari Jamal Nasar Al-Sabahi 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2017年第1期306-311,共6页
A comparative study of Cannabis sativa(Hemp)essential constituents obtained by using Supercritical Fluid Extraction(SCFE),Steam Distillation(SD)and Hydrodistillation(HD)is presented here.The optimized extraction tempe... A comparative study of Cannabis sativa(Hemp)essential constituents obtained by using Supercritical Fluid Extraction(SCFE),Steam Distillation(SD)and Hydrodistillation(HD)is presented here.The optimized extraction temperatures were 130,110and 50℃for hydrodistillation,steam distillation and supercritical fluid extraction respectively.The essential oil of C.sativa was analyzed by using Gas chromatography mass spectrometry(GC-MS).A total of 33,30and 31components have been identified in HD,SD and SCFE respectively.Yield of essential oil using SCFE(0.039%)was more than HD(0.025%)and SD(0.035%)extraction respectively.The main component of sesquiterpenes obtained by hydrodistillation at 130℃with their percentages included caryophyllene(40.58%),trans-α-bergamotene(5.41%),humulene(10.97%),cis-β-farnesene(8.53%)and monoterpenes includedα-pinene(2.13%),d-limonene(6.46%),p-cymol(0.65%)and cineole(2.58%)respectively.The main component of sesquiterpenes obtained by SD steam distillation at110℃including caryophyllene(38.60%)trans-α-bergamotene(4.22%),humulene(10.26%),cis-β-farnesene(6.67%)and monoterpenes includedα-pinene(3.21%),d-limonene(7.07%),p-cymol(2.59%)and cineole(3.88%)whereas the more percentages of major components were obtained by SCFE at 50℃included caryophyllene(44.31%),trans-α-bergamotene(6.79%),humulene(11.97%)cis-β-farnesene(9.71%)and monoterpenes includedα-pinene(0.45%),d-limonene(2.13%)p-cymol(0.19%)and cineole(1.38%)respectively.We found yield/efficiency,chemical composition,quality of the essential oils by supercritical fluid extraction superior in terms of modern,green,saving energy and a rapid approach as compared to traditional techniques. 展开更多
关键词 Cannabis sativa Essential oil HyDRODISTILLATION Steam distillation Supercritical fluid extraction Temperature PRESSURE yield
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Comparative evaluation of modified neem leaf, neem leaf and woodash extracts on soil fertility improvement, growth and yields of maize (<i>Zea mays</i>L.) and watermelon (<i>Citrullus lanatus</i>) (Sole and Intercrop) 被引量:3
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作者 Emmanuel Ibukunoluwa Moyin-Jesu 《Agricultural Sciences》 2012年第1期90-97,共8页
Two field experiments were carried out at Akure (7oN, 5o101E) in the rainforest zone of Nigeria in 2006 and 2007 to determine the effectiveness of neem leaf, woodash and modified neem leaf extracts as fertilizer sourc... Two field experiments were carried out at Akure (7oN, 5o101E) in the rainforest zone of Nigeria in 2006 and 2007 to determine the effectiveness of neem leaf, woodash and modified neem leaf extracts as fertilizer sources in improving soil fertility, growth and yield of maize (Zea mays L) and watermelon (Citrulus lanatus) sole and intercrop. There were six treatments namely, poultry manure, neem leaf extract (sole), woodash extract, modified neem leaf (neem leaf + woodash), NPK 15-15-15 and a control (no fertilizer nor extract), replicated three times and arranged in a randomized complete block design (RCB). The extracts (neem leaf, wood ash and modified neem leaf) were applied at 1200 litres per hectare each, NPK 15-15-15 at 300 kg/ha and poultry was applied at 6t/ha. The results showed that there were significant increases (P 2O), K, Ca, Mg, Na, O.M, P and N compared to NPK 15-15-15 and neem leaf extract. For instance, modified neem leaf extract increased soil pH (H2O), K, Ca, Mg, Na, O.M, P and N by 12.4%, 32.8%, 25%, 23.7%, 19.32%, 17.24% and 20% respectively compared to neem leaf extract under intercrop plot. The high soil K/Ca, K/Mg and P/Mg ratios in the NPK 15-15-15 fertilizer treatment led to an imbalance in the supply of P, K, Ca and Mg nutrients to maize and watermelon crops. The least values for growth, yield and soil parameters were recorded under the control treatment. In these experiments, modified neem leaf extract (woodash + neem leaf extracts) applied at 1200 litres/ha was the most effective in improving soil fertility, growth and yield of maize and watermelon (sole and intercrop) and could substitute for 6 tons per hectare of poultry manure and 300kg/ha of NPK 15-15-15 fertilizer. 展开更多
关键词 Modified NEEM LEAF NEEM LEAF Wood Ash extracts Maize and WATERMELON (Intercrop and Sole) Land Equivalent Ratio Relative yield Poultry Manure
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稀土Y对TiZrNb中熵合金组织及性能的影响
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作者 耿甜甜 李炳 +3 位作者 范新会 李想 李宗茂 谭本立 《铸造》 CAS 2024年第11期1506-1511,共6页
采用真空感应熔炼铸造的方法制备出TiZrNb、TiZrNbY_(0.25)和TiZrNbY_(0.5)三种中熵合金,研究了稀土元素Y对TiZrNb合金的组织结构、力学性能以及耐蚀性能的影响。结果表明,随着Y含量的增加,合金晶粒组织得到细化,成分更加均匀,但在枝晶... 采用真空感应熔炼铸造的方法制备出TiZrNb、TiZrNbY_(0.25)和TiZrNbY_(0.5)三种中熵合金,研究了稀土元素Y对TiZrNb合金的组织结构、力学性能以及耐蚀性能的影响。结果表明,随着Y含量的增加,合金晶粒组织得到细化,成分更加均匀,但在枝晶间形成了少量的富Y,富Zr及Ti_(4)Nb相。稀土Y的添加,提高了TiZrNb合金的压缩屈服强度,但TiZrNbY_(0.5)合金枝晶间析出较多强度较差的富Y相,其压缩屈服强度低于TiZrNbY_(0.25)合金。此外,Y元素提高了TiZrNb合金的耐蚀性能,TiZrNbY_(0.25)合金在1 mol/L HCl溶液中的腐蚀电流密度仅为4.71×10^(-7)A/cm^(2)。 展开更多
关键词 稀土y 中熵合金 显微组织 屈服强度 耐蚀性能
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PV Solar Yield Applicable Simulator Based on Free Irradiance Data Source:Applied Comprehensive Tool for Solar Engineers
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作者 Ahmed Mohamed Ragab Abdelhalim Abdelnaby Zekry Ashraf Yahia Hassan 《Energy Engineering》 EI 2023年第4期885-909,共25页
Accurate PV system simulators are implemented with expensive software platforms using paid irradiance data.The main purpose of this paper is to develop and validate a PV system simulator,beginning with a solar cell pa... Accurate PV system simulators are implemented with expensive software platforms using paid irradiance data.The main purpose of this paper is to develop and validate a PV system simulator,beginning with a solar cell parameter extraction model,then test and validate long-termIrradiance data using free online source(Typical Meteorological Year TMY in(PVGIS)European website),and finally building full solar generator simulator to run in working real conditions.Comparing results with Accurate Paid PV simulators(which use theMuneer model)showed good accuracy of the proposed simulator.Work flow starts with the Irradiance model’s data processing,then solar cell 5 parameters model data processing(to extract cell parameters),and finally full system simulator.MATLAB coding programs in real working conditions are used for simulation.Results of solar cell parameter extraction show 99.6%to 99.99%matching with data sheet and cell performance under standard test conditions.Systemmodel simulation output shows 8%less yearly generated energy compared to the PVGIS 2022 long-term simulation(hourly basis(one-year time)).This is due to incident energy variations(between the years 2016 and 2022)of 4.02%.The novelty of the algorithm is the methodology,as it tests irradiance data on an hourly basis and validates results for a whole continuous year.Also,the 5-parameter solar cell model is used to be validated in long term analysis,not only STC conditions and could be applied on any PV solar cell.The algorithm and block diagramused are scalable,modular,and interchangeable with similarmodels to be tested.This simulator could test severalmethods andmodels in solar pv technology. 展开更多
关键词 Photovoltaics solar systems solar cell parameters extraction solar simulationmodel irradiancemodels solar yield long term analysis
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Effect of Temperature on Extraction of Castor Oil from Castor Seeds Using Potential Green Solvents
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作者 Zinhle Innocentia Mkhize Peterson Thokozani Ngema Suresh Ramsuroop 《Advances in Chemical Engineering and Science》 2023年第4期301-317,共17页
Extraction of castor oil from castor seeds was investigated using different green solvents which include d-limonene, p-cymene, α-pinene, ethanol, and furfural at the temperature range of (323 - 413) K. The Soxhlet ex... Extraction of castor oil from castor seeds was investigated using different green solvents which include d-limonene, p-cymene, α-pinene, ethanol, and furfural at the temperature range of (323 - 413) K. The Soxhlet extraction method was employed to investigate the effect of temperature at atmospheric pressure. The focus of the study was to investigate a potential green solvent that can produce the high yields compared to the traditional solvent (hexane). The results show that at the average time of 3 hours and 30 minutes, the castor oil yield for green solvents were ranked as furfural (47.13%) > ethanol (45.37%) > p-cymene (39.15%) > d-limonene (39.13%) > α-pinene (38.11%). These castor oil yields were obtained at optimum temperatures for each green solvent. The castor oil yields were compared to the yield of hexane (31.36%) at same average time. The green solvents were recovered by using simple distillation, except furfural which was difficult to be recovered. 展开更多
关键词 Castor Oil yield Soxhlet extraction Green Solvents
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Extraction of Pumpkin Polysaccharide by Complex Enzyme Method and Its Antioxidant Research 被引量:20
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作者 孙婕 尹国友 +2 位作者 陈兰英 Guo-you Lan-ying 《Agricultural Science & Technology》 CAS 2010年第5期34-37,共4页
[Objective] This paper aims to study a new method of extracting pumpkin polysaccharide from pumpkin. Single factor experiments were conducted to examine the effects of extracting time,temperature,the solid-liquid rati... [Objective] This paper aims to study a new method of extracting pumpkin polysaccharide from pumpkin. Single factor experiments were conducted to examine the effects of extracting time,temperature,the solid-liquid ratio and pH value on the extraction yield of polysaccharide from pumpkin. [Method] The best enzyme ratio and extraction conditions for complex enzymes extraction were determined through orthogonal tests. Scavenging ·OH and O-2 activities of pumpkin polysaccharides were also investigated by salicylic acid and improved self-oxidation of o-pheno methods respectively. [Results] The results showed that the biggest extraction yield of polysaccharide from pumpkin can be got when adding 1% cellulose enzyme,1.5% pectinase,1.0% papain and Na2HPO4-citric acid buffer solution (pH was 4.6),and oscillating for 30 min under water at 40 ℃ with the solid-liquid ratio of 1:30. In addition,pumpkin polysaccharides had a strong activity of eliminating ·OH,but very weak activity to scavenge O-2. [Conclusion] This study provided basic data for research and application of Pumpkin polysaccharide. 展开更多
关键词 Complex enzymes method Pumpkin polysaccharide extraction Antioxidant activity
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连梁可更换的Y型偏心支撑组合框架力学性能试验研究
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作者 吴桢灏 庄亮东 黄远 《工程力学》 EI CSCD 北大核心 2024年第3期173-186,共14页
为研究连梁可更换的Y型偏心支撑组合框架(简称“Y型V-EBCF”)的力学性能,设计制作了一榀Y型V-EBCF试件,其中可更换式连梁由低屈服点钢加工并通过高强螺栓与周边构件相连。对Y型V-ECBF试件和拆卸了连梁后的试件分别进行了拟静力试验,分... 为研究连梁可更换的Y型偏心支撑组合框架(简称“Y型V-EBCF”)的力学性能,设计制作了一榀Y型V-EBCF试件,其中可更换式连梁由低屈服点钢加工并通过高强螺栓与周边构件相连。对Y型V-ECBF试件和拆卸了连梁后的试件分别进行了拟静力试验,分析了试件的失效模式、荷载-位移曲线和残余位移角,试验结果表明:在连梁失效前,结构具有稳定的滞回性能和良好的耗能能力;当拆卸失效连梁后,结构在组合框架的不平衡内力下恢复至原位,残余变形角为0.002 rad,小于规范限值(0.005 rad)及最大可更换残余位移角限值(0.0023 rad),且余下试件再加载时的滞回曲线依旧饱满稳定,表明Y型V-ECBF体系具有良好的震后恢复能力;采用现行AISC360-16规范相关公式可以准确计算低屈服点钢连梁的承载力,但超强系数建议取3.0以防止周边构件的破坏;Y型V-ECBF体系的刚度和承载力等于偏心支撑中连梁和组合框架的刚度与承载力之和。此外,Y型V-EBCF中的连梁会引起框架梁跨中承担额外的弯矩,导致跨中混凝土板的开裂,该文给出了计算跨中混凝土板裂缝宽度的公式。 展开更多
关键词 y型偏心支撑组合框架 可更换连梁 低屈服点钢 试验研究 力学性能 设计建议
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Fractional Yield, Extract Composition and Variability from Jordanian Oil Shales 被引量:1
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作者 Hani M. Alnawafleh Feras Y. Fraige +2 位作者 Khalid E. Tarawneh Ibrahim A. Sarairahc Laila A. Al-Khatib 《Journal of Analytical Sciences, Methods and Instrumentation》 2016年第3期51-63,共13页
Surface and subsurface oil shale (OS) rocks in Jordan have potential economic value for the country and still unutilized. This research paper focuses on central and southern OS deposits in Jordan. Brief characterizati... Surface and subsurface oil shale (OS) rocks in Jordan have potential economic value for the country and still unutilized. This research paper focuses on central and southern OS deposits in Jordan. Brief characterization of four OS deposits is presented. Size distribution test and elemental analysis were performed. Shale oil was extracted via three solvation methods: Soxhlet extraction, extraction via mixing and stirring, and lastly super-critical fluid extraction. Major shale oil fractions were obtained from extract fractionation on chromatographic column. The nuclear magnetic resonance spectroscopy technique was used to study qualitatively the fractional composition of OS extract. Results show that all studied OS deposits have quite similar trend in their particle size distribution and their elemental composition. These OS deposits are found to be varying in their solvation behavior, fractional yield, and shale oil composition. Highest yield is obtained from polar solvents. The OS extraction via solvation processes is promising under certain extraction conditions such as super-critical conditions. The solvation variability of Jordanian OS indicates that different extraction techniques suit different OS deposits. Such variability should be considered in any future extraction options. 展开更多
关键词 JORDAN Oil Shale Solvent extraction VARIABILITy Fractional yield
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Structure Reactivity Studies on the Extraction of Rare Earths by Di(2-ethylhexyl)chloroalkyl Phosphonates
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作者 叶伟贞 严金英 《Journal of Rare Earths》 SCIE EI CAS CSCD 1992年第3期179-182,共4页
The extractive separation properties and the extractive regularity of the lanthanide elements by five di(2-ethylhexyl)alkyl phosphonates with various alkyl structure:di(2-ethylhexyl)chloromethyl phosphonate CH_2ClP(O)... The extractive separation properties and the extractive regularity of the lanthanide elements by five di(2-ethylhexyl)alkyl phosphonates with various alkyl structure:di(2-ethylhexyl)chloromethyl phosphonate CH_2ClP(O) (OC_8H_(17)-i)_2(1),di(2-ethylhexyl)β-chloroethyl phosphonate ClCH_2CH_2P(O) (OC_8H_(17)-i)_2 (2),di(2-ethylhexyl)α-chloroethyl phosphonate CH_3CHClP(O)(OC_8H_(17)-i)_2 (3),and corresponding di(2-ethylhexyl)methyl phosphonate CH_3P(O)(OC_8H_(17)-i)_2 (4),di(2-ethylhexyl)ethyl phosphonate C_2H_5P(O) (OC_8H_(17)-i)_2 (5),in nitrate system have been studied.The coordination compounds were prepared. The structure of these extractants and their coordination compounds were further explored by IR and ^(31)P NMR spectra. 展开更多
关键词 RE y extraction IR ^(31)P NMR Di(2-ethylhexyl)chloroalkyl phosphonate
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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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Predicting Mass Transfer Extraction with Steam Flow, Applying Boundary-Layer Concepts
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作者 Jose Antonio Rocha-Uribe Laura Catalina Soto-Armenta +1 位作者 Alfredo Raul Hernandez-Ruiz Jorge Ciro Jimenez-Ocaña 《Journal of Materials Science and Chemical Engineering》 2021年第6期46-58,共13页
Theory and concepts of boundary layer mass transfer is applied to correlate experimental data on extraction of essential oils from vegetable leaves and stems, using steam. From these theory, concepts and experimental ... Theory and concepts of boundary layer mass transfer is applied to correlate experimental data on extraction of essential oils from vegetable leaves and stems, using steam. From these theory, concepts and experimental data with seven systems, two correlations are developed to predict the Sherwood number and mass transfer coefficient as function of Reynolds and Schmidt numbers. From these equations, the molar flux, the amount of solute extracted, and the yield of extraction is predicted. A steam of higher temperature normally improves the mass transfer and the yield. A method to estimate the enhancement for temperature increase is proposed. The correlations developed are applied to a case with industrial size that was no part of the data for correlation generation. Theory may be applied for industrial applications. 展开更多
关键词 Boundary Layer Essential Oil extraction yield Steam Distillation Mass Transfer Coefficient
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Study on Response Surface Methodology Optimization for Extraction Process of Cyclocarya paliurus Extract and Its Blood Sugar-lowering Effect
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作者 Yufeng LI Xiayun LIAO +1 位作者 Gang WANG Lichun ZHAO 《Agricultural Biotechnology》 CAS 2020年第5期127-133,共7页
[Objectives]This study was conducted to discuss the mechanism of the blood sugar-lowering effect of Cyclocarya paliurus extract.[Methods]With C.paliurus leaves as the raw material,the ethyl acetate-butyl acetate micro... [Objectives]This study was conducted to discuss the mechanism of the blood sugar-lowering effect of Cyclocarya paliurus extract.[Methods]With C.paliurus leaves as the raw material,the ethyl acetate-butyl acetate microwave extraction process of C.paliurus was studied.With the yield of C.paliurus extract as an evaluation index,single-factor experiments were carried out on such 6 factors as the dry C.paliurus leaf powder size,solid-to-liquid ratio,extraction time,microwave frequency,microwave power,and microwave extraction time,and the extraction and purification process was further optimized by response surface analysis.The normal mice and the hyperglycemic mice modeled by alloxan were injected with C.paliurus extract to study the blood sugar-lowering effects of different groups of C.paliurus extract.[Results]The optimal process combination for the extraction of C.paliurus leaves was obtained:dry C.paliurus powder size 90-100 mesh,solid-to-liquid ratio 1∶20(g/ml),extraction time 192 min,microwave frequency 2500 MHz,microwave power 490 W,and extraction time 248 s.Under these conditions,the yield of C.paliurus extract reached the maximum,95.10%,reaching 99.83%of the predicted value.The blood sugar-lowering test on mice showed that the C.paliurus extract had a good effect on lowering blood sugar,indicating that C.paliurus extract can improve the free radical scavenging capacity to a certain extent.[Conclusions]This study provides certain reference for the in-depth study of the physiological effects of C.paliurus extract and the comprehensive development and utilization of C.paliurus extract. 展开更多
关键词 Cyclocarya paliurus C.paliurus extract yield Blood sugar lowering Radical scavenging
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Bone Marrow Mononuclear Cell Extraction. Does the Operator Performance Affect Processing Efficacy?
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作者 Jakobsons Eriks Cakstina Inese +9 位作者 Erglis Kristaps Erglis Martins Pirtniece Liene Elina Krumina NarbuteInga Briede Ieva Jegere Sanda Smolova Rita Muiznieks Indrikis Erglis Andrejs 《Journal of Pharmacy and Pharmacology》 2016年第5期192-198,共7页
Different cell populations from bone marrow are used in various clinical trials for cardiac diseases during last decade. Four clinical studies are on going in our institution and enrol patients with cardiac diseases, ... Different cell populations from bone marrow are used in various clinical trials for cardiac diseases during last decade. Four clinical studies are on going in our institution and enrol patients with cardiac diseases, coronary disease and type 2 diabetes, patients with osteoarthritis. Density gradient is used to separate bone marrow mononuclear cells. Cell processing looses are significant. To find out critical control points we analysed processing process and differences in cell yields between operators performing cell extraction. Bone marrow mononuclear cells were isolated using Ficoll density gradient centrifugation. Cells were counted using flow cytometry for mononuclear cell total counts, CD34+ population count and viability analysis. The patients who underwent bone marrow aspiration followed by cell isolation received cell suspension for transplantation. Two cells processing for separate patients were performed at once. Same standard operation procedures were applied. Processing looses between operators performing cell extraction were analysed. Bone marrow samples from eight patients were processed. Mononuclear cells were extracted. Operator performances were compared. Operator A average bone marrow mononuclear cell yield in starting material was 9,97 ± 9,98 %, CD34+ population yield 75,46±79,67%. Operator B average bone marrow mononuclear cell yield in starting material was 24,68 ± 14,8 %, CD34+ population yield 70,42 ±44.84%. Operator A average cell viability in starting material was 45,24 ± 9,55%, after cell processing 42,96 ± 23,66 %. Operator B average cell viability in starting material was 49,85 ± 5,48%, after cell processing 69,52 ± 6,65 %. 展开更多
关键词 Bone marrow mononuclear cells cell yield cell extraction cell count
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Y型智能分采管柱在渤海油田的应用分析
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作者 耿森 范子涛 王志文 《石化技术》 CAS 2024年第2期60-62,共3页
对Y型智能分采管柱的结构和优点进行了介绍,强调了其高效生产调配的优点,极大地节约了生产成本。讨论了Y型智能分采管柱的工艺设计。重点探讨了Y型智能分采管柱在渤海油田M13井的实际应用情况,分析了其带来的显著优势和效果。通过该案... 对Y型智能分采管柱的结构和优点进行了介绍,强调了其高效生产调配的优点,极大地节约了生产成本。讨论了Y型智能分采管柱的工艺设计。重点探讨了Y型智能分采管柱在渤海油田M13井的实际应用情况,分析了其带来的显著优势和效果。通过该案例的研究,充分展示Y型智能分采管柱在海洋石油开采中的价值和潜力。为进一步推广和应用Y型智能分采管柱技术提供了有益的实践经验和参考依据。 展开更多
关键词 电潜泵 y型智能分采管柱 技术应用
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黄晶梨Y形篱壁树形早期产量调查与栽培技术要点
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作者 赵芳 王秀荣 +1 位作者 刘娜 许夕之 《落叶果树》 2024年第4期28-30,共3页
黄晶梨在山东地区表现优良,结果早,能自花授粉结实,丰产。采用Y形树形的黄晶梨幼树调查分析表明,苗木栽植第4年进入盛果期,666.7 m^(2)枝量87293条,其中,长枝、中枝、短枝,分别占总枝量的12.02%、7.74%、80.24%,产量达到3330 kg。介绍... 黄晶梨在山东地区表现优良,结果早,能自花授粉结实,丰产。采用Y形树形的黄晶梨幼树调查分析表明,苗木栽植第4年进入盛果期,666.7 m^(2)枝量87293条,其中,长枝、中枝、短枝,分别占总枝量的12.02%、7.74%、80.24%,产量达到3330 kg。介绍了其栽培技术要点。 展开更多
关键词 黄晶梨 y形树形 枝类构成 产量
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Effects of Peat Extract on Crop Yields
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作者 LuoShengguo LiuShiyong 《Journal of Northeast Agricultural University(English Edition)》 CAS 1998年第2期104-110,共7页
This paper reports the results of plot experiments canducted in 1991~1993 on the effects of a new plant growth regulator Shibide (SBD) on the yields of 4 grain crops, 5 vegetables and 2 cash crops. It also reports th... This paper reports the results of plot experiments canducted in 1991~1993 on the effects of a new plant growth regulator Shibide (SBD) on the yields of 4 grain crops, 5 vegetables and 2 cash crops. It also reports the effect of this product on plant growth vigors such as plant height, leaf width and diameter of plant stem. 展开更多
关键词 Shibide(SBD) peat extract crop yields
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A laboratory modification to testicular sperm preparation technique improves spermatogenic cell yield 被引量:2
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作者 Sinan Ozkavukcu Ebru Ibis +2 位作者 Sule Kizil Suheyla Isbacar Kaan Aydos 《Asian Journal of Andrology》 SCIE CAS CSCD 2014年第6期852-857,共6页
Testicular sperm extraction is a common procedure used to find spermatogenic cells in men with nonobstructive azoospermia. The laboratory processing of biopsied testicular tissues needs to be performed meticulously to... Testicular sperm extraction is a common procedure used to find spermatogenic cells in men with nonobstructive azoospermia. The laboratory processing of biopsied testicular tissues needs to be performed meticulously to acquire a high yield of cells. In this study, the effectiveness of mincing the tissues after testicular biopsy was assessed using histological evaluation, as was the possible adverse effect of residual tissue on the migration of spermatogenic cells during density gradient centrifugation. Our results indicate that testicular residual tissue, when laid on the density gradient medium along with the sperm wash, hinders the spermatogenic cells' forming a pellet during centrifugation, and therefore impairs the intracytoplasmic sperm injection procedure. Whereas the mean number of recovered cells from the sperm wash medium (SWM) with residual tissue is 39.435 ~ 24.849, it was notably higher (60.189 ~ 28.214 cells) in the SWM without minced tissues. The remaining tissue contained no functional seminiferous tubules or spermatogenic cells in histological sections. In conclusion, the remaining residual tissue after mincing biopsied testicular tissue does not add any functional or cellular contribution to spermatogenic cell retrieval; in fact, it may block the cellular elements in the accompanying cell suspension from migrating through the gradient layers to form a pellet during centrifugation and cause loss of spermatogenic cells. 展开更多
关键词 assisted reproductive techniques AZOOSPERMIA gradient density centrifugation sperm yield testicular sperm extraction
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Alkaline extraction characteristics of steelmaking slag batch in NH_4Cl solution under environmental pressure 被引量:2
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作者 张慧宁 徐安军 +1 位作者 贺东风 崔健 《Journal of Central South University》 SCIE EI CAS 2013年第6期1482-1489,共8页
In order to obtain better carbonation effect, extraction behavior of slag batch is necessary to study. Relevant parameters like selective extraction yield were originally discussed. The relationship between selective ... In order to obtain better carbonation effect, extraction behavior of slag batch is necessary to study. Relevant parameters like selective extraction yield were originally discussed. The relationship between selective extraction yield and conversion ratio was systemically focused on. The results show that alkaline earth metal conversion ratio is changed with leaching time and NH4CI concentration by first order exponential, and the maximum conversion for calcium keeps about 68% at 120 min in 0.4 mol/L NH4C1 solution, while leaching temperature and particle size have a linear effect on conversion ratio. Selective extraction yield of calcium is more than 93%, and the value of Mg is less than 5%. Apparent layer bands of silicon and calcium appear in the surface area through morphology detection of slag after leaching, and the case for 38-75 μm slag batch is more obvious than 75 150 μm slag and slag with larger particle size when leaching in 0.4 mol/L NH4Cl solution for 90 rain at 60 ℃. 展开更多
关键词 steel slag alkaline leaching NH4Cl solution selective extraction yield conversion ratio
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