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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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Effects of Ultrasound-Assisted Alkaline Extraction on the Structural and Emulsifying Properties of Chickpea Protein Isolate
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作者 ZHANG Yixue YANG Qing +4 位作者 CHENG Teng ZHENG Ruihan MA Wuchao HE Xiangli LI Ke 《食品科学》 北大核心 2025年第19期236-247,共12页
This study aimed to investigate the effect of ultrasound-assisted alkaline extraction(UAE)(at 20 kHz and different powers of 0,200,300,400,500 and 600 W for 10 min)on the yield,structure and emulsifying properties of ... This study aimed to investigate the effect of ultrasound-assisted alkaline extraction(UAE)(at 20 kHz and different powers of 0,200,300,400,500 and 600 W for 10 min)on the yield,structure and emulsifying properties of chickpea protein isolate(CPI).Compared with the non-ultrasound group,ultrasound treatment at 400 W resulted in the largest increase in CPI yield,and both the particle size and turbidity decreased with increasing ultrasound power from 0 to 400 W.The scanning electron microscope results showed a uniform structural distribution of CPI.Moreover,itsα-helix content increased,β-sheet content decreased,and total sulfhydryl group content and endogenous fluorescence intensity rose,illustrating that UAE changed the secondary and tertiary structure of CPI.At 400 W,the solubility of the emulsion increased to 63.18%,and the best emulsifying properties were obtained;the emulsifying activity index(EAI)and emulsifying stability index(ESI)increased by 85.42%and 46.78%,respectively.Furthermore,the emulsion droplets formed were smaller and more uniform.In conclusion,proper UAE power conditions increased the extraction yield and protein content of CPI,and effectively improved its structure and emulsifying characteristics. 展开更多
关键词 CHICKPEA ULTRASOUND extraction yield protein structure functional properties
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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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超声波-高压咖啡冷萃系统工艺设计与试验
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作者 苏微 翟国栋 +4 位作者 赖庆辉 董文江 张玉凝 阙煜 王晓阳 《农机化研究》 北大核心 2026年第3期202-210,共9页
针对传统冷萃工艺耗时、设备效率不足和冷萃咖啡关键制备工艺不成熟等问题,结合超声波萃取技术和高压萃取技术,设计和开发了一种超声波-高压咖啡冷萃系统和工艺。通过在萃取釜上增设可拆卸超声振动组件,将超声波萃取技术和高压萃取技术... 针对传统冷萃工艺耗时、设备效率不足和冷萃咖啡关键制备工艺不成熟等问题,结合超声波萃取技术和高压萃取技术,设计和开发了一种超声波-高压咖啡冷萃系统和工艺。通过在萃取釜上增设可拆卸超声振动组件,将超声波萃取技术和高压萃取技术在同一个容器中进行,缩短萃取工作时长,提高咖啡冷萃效率。利用单因素试验和混合水平正交试验,对超声波冷萃咖啡进行萃取率检测,确定处理1 kg咖啡粉萃取率的最佳超声参数方案为萃取时间30 min、功率1 800 W、频率20 kHz。在咖啡萃取率最佳超声方案的基础上,进行整机萃取试验,结果表明:萃取率随压力增加和萃取时间延长呈上升趋势,其中10~20 min内增速较好,超过20 min后萃取率超过20%,压力在0.6~0.8 MPa区间内萃取率提升显著,0.8 MPa以上增速趋缓;选用萃取压力和萃取时间作为因素进行均匀设计试验,结果表明:最优压力萃取参数为压力1.2 MPa、压力萃取时间10 min。研究可为咖啡精深加工和高值化产品研发提供理论依据和技术支撑。 展开更多
关键词 冷萃咖啡 超声波萃取 高压萃取 萃取率 混合水平正交试验 均匀设计试验
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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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利尿消炎合剂提取工艺优选
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作者 张飞 高珊 +2 位作者 李卓亚 刘锐锋 赵伟国 《中国药业》 2026年第3期73-76,共4页
目的优化利尿消炎合剂的提取工艺。方法以浸泡时间、加水量、煎煮时间、煎煮次数为考察因素,以盐酸小檗碱转移率和出膏率为综合评价指标,采用L_(9)(3^(4))正交试验法优选利尿消炎合剂的提取工艺,并进行验证。结果最佳提取工艺为加10倍量... 目的优化利尿消炎合剂的提取工艺。方法以浸泡时间、加水量、煎煮时间、煎煮次数为考察因素,以盐酸小檗碱转移率和出膏率为综合评价指标,采用L_(9)(3^(4))正交试验法优选利尿消炎合剂的提取工艺,并进行验证。结果最佳提取工艺为加10倍量水,浸泡1.0 h,煎煮3次,每次1.5 h。按此工艺制备的3批样品中,平均盐酸小檗碱转移率为15.99%,平均出膏率为17.73%。结论优选工艺稳定、合理、可行,可用于利尿消炎合剂的制备。 展开更多
关键词 利尿消炎合剂 L_(9)(3^(4))正交试验法 盐酸小檗碱 转移率 出膏率 提取工艺
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槐豆胶制备工艺优化及其理化性质
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作者 王婷 杨淋 +2 位作者 张璐 张民 李茜 《食品研究与开发》 2026年第1期83-92,共10页
该试验以超高压槐角和未超高压槐角为原料,采用超声辅助复合酶解法水提槐豆胶;通过单因素试验考察提取温度、混合酶添加量、酶解时间、料液比对槐豆胶提取得率的影响,并在单因素试验结果的基础上开展响应面优化试验,利用优化后的条件对... 该试验以超高压槐角和未超高压槐角为原料,采用超声辅助复合酶解法水提槐豆胶;通过单因素试验考察提取温度、混合酶添加量、酶解时间、料液比对槐豆胶提取得率的影响,并在单因素试验结果的基础上开展响应面优化试验,利用优化后的条件对槐豆胶进行分离纯化,得到均一多糖组分;再通过高效液相色谱、低温差示量热扫描仪、刚果红染色法等对槐豆胶的组成、结构及理化特性进行分析。结果表明,最佳提取条件为提取温度90℃、混合酶添加量0.4%、酶解时间1.5 h、料液比1∶20(g/mL)。此时,使用超高压原料提取的槐豆胶提取得率达到(19.30±0.12)%,与未超高压原料相比,槐豆胶提取得率增加6.17%。槐豆胶的组成及结构研究表明,槐豆胶相对分子量为7.60×10^(4)~2.45×10^(6)Da;4个醇沉组分的单糖组成为半乳糖(Gal)、甘露糖(Man)、葡萄糖(Glc)、阿拉伯糖(Ara)、木糖(Xyl)、鼠李糖(Rha),其中Man、Glc和Gal是主要的单糖成分;使用超高压原料提取得到的槐豆胶在持水力、持油力和膨胀力方面相对较高;低温差示量热扫描结果显示槐豆胶有较好的热稳定性;刚果红染色表明槐豆胶的4个组分均不具备三螺旋结构特征。 展开更多
关键词 槐豆胶 制备工艺优化 单因素试验 提取得率 理化性质
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基于Box-Behnken响应面法结合正交试验的达原饮提取工艺优化
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作者 刘菊 金云隆 +3 位作者 孔祥才 高晓洁 张红伟 白明学 《中国现代中药》 2026年第1期158-165,共8页
目的:优化达原饮的提取工艺和灭菌工艺。方法:以加水量、提取时间、提取次数为考察因素,以达原饮中10个有效成分的总含量、浸膏得率为评价指标,通过Box-Behnken响应面法建立模型,优选达原饮的最佳提取工艺并进行验证实验。采用正交试验... 目的:优化达原饮的提取工艺和灭菌工艺。方法:以加水量、提取时间、提取次数为考察因素,以达原饮中10个有效成分的总含量、浸膏得率为评价指标,通过Box-Behnken响应面法建立模型,优选达原饮的最佳提取工艺并进行验证实验。采用正交试验,以灭菌温度、灭菌压力、灭菌时间为考察因素,以灭菌后达原饮中微生物测定结果和10个有效成分的总含量为评价指标,优选达原饮的最佳灭菌工艺。结果:达原饮的最佳提取工艺为加水量10倍、提取时间1.5 h,提取2次;最佳灭菌工艺为灭菌温度100℃、灭菌压力60 kPa、灭菌时间45 min。结论:优选的达原饮提取工艺和灭菌工艺简便易行、稳定性好,为达原饮的产业化生产提供参考。 展开更多
关键词 达原饮 Box-Behnken响应面法 正交试验 浸膏得率 有效含量
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消渴一号方煎煮工艺的实践导向型优化
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作者 郭璐 曾丽雯 +1 位作者 胡玉座 邵旭红 《中国处方药》 2026年第1期29-33,共5页
目的以院内煎煮实践为导向优化院内协定方消渴一号方的煎煮工艺。方法以浸泡时间、加水量、一煎时间、二煎时间为考察因素,以总多糖浓度、浸膏粉得率、得液量为综合评价指标,进行单因素试验,并根据实验结果设计L_(9)(3^(4))正交试验进... 目的以院内煎煮实践为导向优化院内协定方消渴一号方的煎煮工艺。方法以浸泡时间、加水量、一煎时间、二煎时间为考察因素,以总多糖浓度、浸膏粉得率、得液量为综合评价指标,进行单因素试验,并根据实验结果设计L_(9)(3^(4))正交试验进一步优化消渴一号方煎煮工艺。结果经过正交试验及工艺验证试验筛选验证,消渴一号方最佳煎煮条件为浸泡1 h,加水3.3 L,一煎20 min,二煎30min。结论采用紫外分光光度法,应用苯酚及浓硫酸,通过正交试验获得了消渴一号方的最佳煎煮工艺,该工艺条件可在保障汤剂煎煮质量的前提下节约医院时间成本、患者经济成本。 展开更多
关键词 协定方 总多糖浓度 浸膏粉得率 得液量 煎煮工艺
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Alkaline extraction characteristics of steelmaking slag batch in NH_4Cl solution under environmental pressure 被引量:3
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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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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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Extraction of Cinnamomum longepaniculatum deciduous leaves essential oil using solvent-free microwave extraction: Process optimization and quality evaluation 被引量:4
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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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Optimization of Response Surface of Ultrasonic-assisted Extraction of Rizhao Black Tea 被引量:1
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作者 TANG Yu-huan LIANG Qing +2 位作者 ZOU Jia-jia DING Xin DING Li-xiao 《Chinese Food Science》 2012年第3期35-38,共4页
[ Objectivel The aim was to determine the optimal technology for ultrasonic-assisted extraction of black tea was determined. [ Methed] Taking Black Tea as materials, the Box-Behnken response surface design method of t... [ Objectivel The aim was to determine the optimal technology for ultrasonic-assisted extraction of black tea was determined. [ Methed] Taking Black Tea as materials, the Box-Behnken response surface design method of tea polyphenols ultrasonic-assisted extraction process optimi- zation was applied. The regression optimization model of the ethanol volume fraction, ultrasonic time, and ultrasonic temperature, ethyl acetate extract stalling time and tea polyphenols was established. [ Result] The influence of four factors on the black tea polyphenol solvents affecting size was as follows: ultrasonic time 〉 ethanol volume fraction 〉 stalling extraction time 〉 ultrasound temperature. The best extraction process was ultrasonic time 80 min, volume fraction of 88.99% ethanol, extraction time 89.97 min, ultrasonic temperature of 80℃. At the optimized technical parameters, the black tea phenolic extraction yield can be as high as 73.50%. [ Conclusion] The study provided theoretical basis for the development of tea leaves and black tea. 展开更多
关键词 Rizhao black tea Ultrasonic-assisted extraction extraction yield Response surface China
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Metal Extraction Process for High Grade Stibnite of Kharan (Balochistan Pakistan) 被引量:1
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作者 Irfan Hafeez Saqib Nasir +3 位作者 Samreen Zahra Muhammad Aamir Zahid Mahmood Adnan Akram 《Journal of Minerals and Materials Characterization and Engineering》 2017年第1期39-48,共10页
A rapid and simple process has been developed for the recovery of antimony metal from stibnite ore of Kharan area (Balochistan) of Pakistan. The ore was characterized by X-ray diffraction (XRD) technique and found to ... A rapid and simple process has been developed for the recovery of antimony metal from stibnite ore of Kharan area (Balochistan) of Pakistan. The ore was characterized by X-ray diffraction (XRD) technique and found to contain 66% stibnite i.e. antimony sulfide (Sb2S3). The process parameters for the extraction of antimony were optimized on laboratory scale by varying reaction temperature from 900℃ - 1000℃, reaction time from 20 - 80 minutes and flux concentration was varied from 5 - 25 weight percent of the reaction mixture. The metal thus recovered with optimum conditions was evaluated by X-ray fluorescence (XRF) technique and was found to be more than 94% pure. The recovery yield calculated on the basis of stibnite present in the ore was 98.52%. 展开更多
关键词 ANTIMONY STIBNITE extractION RECOVERY yield
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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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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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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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Pressurized Hot Water Extraction of Alkaloids in Goldenseal
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作者 Janes Mokgadi Charlotta Turner Nelson Torto 《American Journal of Analytical Chemistry》 2013年第8期398-403,共6页
A quick, efficient and environmentally beneficial approach for the extraction of alkaloids in goldenseal based on pressurized hot water extraction (PHWE) is presented. PHWE was evaluated following the extraction of hy... A quick, efficient and environmentally beneficial approach for the extraction of alkaloids in goldenseal based on pressurized hot water extraction (PHWE) is presented. PHWE was evaluated following the extraction of hydrastine and berberine which are the two main alkaloids of goldenseal. The effects of temperature and other parameters on extraction yields were monitored by high performance liquid chromatography coupled to diode array detector (HPLC-DAD). The extraction yields were compared to those achieved through reflux and ultrasonic extraction methods. PHWE employed hot water at an optimal temperature of 140℃, a pressure of 50 bars and flow rate of 1 mL.min-1 for extraction experiments conducted in the dynamic mode. Both PHWE and conventional methods achieved comparable extraction yields. Reflux and ultrasonic extractions had procedures that were slower (over 6 h) and employed large quantities (200 mL) of organic solvents. The PHWE method was simple and relatively fast as extraction was achieved in 15 min. At 95% confidence level (n = 3), reflux and ultrasonic methods recorded extraction yields that were not significantly different from that of PHWE. Moreover, PHWE employed a more readily available “green” solvent, (water) to achieve comparable results to those of conventional methods which utilized organic solvents. The percentage relative standard deviations (%RSD) for the extraction yields were less than 3% in all cases indicating the high reproducibility of the method. However, when using PHWE to extract thermally labile analytes like alkaloids, degradation effects also occurred. Increasing the temperatures certainly achieved higher extraction yields but also led to degradation of these thermally labile compounds indicating a necessity for optimization. 展开更多
关键词 SUBCRITICAL Water extractION extractION yieldS DEGRADATION Hydrastine BERBERINE
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Efficacy of aqueous leaf extracts and synthetic insecticide on pod-sucking bugs infestation of cowpea (Vigna unguiculata (L.) Walp) in the Guinea Sa-vanna Region of Nigeria 被引量:1
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作者 Michael M. Degri Duna M. Mailafiya Joshua W. Wabekwa 《Advances in Entomology》 2013年第2期10-14,共5页
Pod-sucking bugs (PSBs) infestation by Ano-plocnemissp./ Riptortussp./Clavigrallasp./Nezaraviridula( Linnaeus) greatly limits cowpea (Vignaunguiculata (L.) Walp) production throughout sub-Saharan Africa. The efficacy ... Pod-sucking bugs (PSBs) infestation by Ano-plocnemissp./ Riptortussp./Clavigrallasp./Nezaraviridula( Linnaeus) greatly limits cowpea (Vignaunguiculata (L.) Walp) production throughout sub-Saharan Africa. The efficacy of aqueous leaf extracts (ALEs) (5 percent weight/volume concentration) of three botanicals and one synthetic insecticide against PSBs infestation was thus evaluated. The botanicals tested include Aza- dirachtaindicaA. Juss, Chromolaenaodorata (L.) and Ricinuscommunis (L.), whilst the synthetic insecticide was Uppercot 500 EC ( Lambda cyhalothrin 30 g + Dimethoate 250 g ). The effects of these treatments on the number of PSBs/ pods/seeds, pod/seed weight and grain yield were assessed during 2008 and 2009 rainy seasons in Bayo, Borno State, Guinea Savanna region, Nigeria. The number of PSBs was lower on crops treated with Uppercot 500 EC (0.00 - 0.31). This was followed by crops treated with the ALEs ofA.indica/C.odorata (0.31 - 1.33) and R.communis (0.72 - 3.72) than the untreated (3.06 - 5.64) ones.The number of pods/pod weight per plant, seeds/seed weight per pod and total grain yield were generally higher on cowpea crops treated with Uppercot 500 EC (26/17 g, 14/19 g and 1618 kg). This was followed bycrops treated with the ALEs of A.indica/C.odorata (23 - 25/14 - 15 g, 12 - 13/15 g and 1268 - 1310 kg) and R.communis( 21/13 g, 11/14 g and 972 kg) than the untreated (16/9 g, 7/10 g and 312 kg) ones. Although Uppercot 500 EC was most effective inprotecting cowpea against PSBs attack, theALEs of A.indica and C.odorata appreciably protected treated crops against infestation, giving relatively high total grain yield. Both botanical scan thus serve as alternatives to synthetic insecticides for managing PSBs attack on cowpea. 展开更多
关键词 COWPEA Pod-Sucking Bugs INFESTATION AQUEOUS Leaf extract SYNTHETIC INSECTICIDE Grain yield
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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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