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Study on Extraction of Polysaccharides from Ganoderma lucidum by Hot Compressed Water and Its Antioxidant Activities(高压热水提取灵芝多糖及对其抗氧化活性的影响) [PDF]

open access: yesShipin kexue jishu xuebao, 2018
With superfine fruiting body powder of Ganoderma lucidum as raw materials, extraction temperature, extraction time, and solid-liquid ratios on the extraction of polysaccharides and the scavenging activity on DPPH radicals were investigated.
CAO Lili(操丽丽)   +6 more
doaj   +1 more source

Optimization of the tannins extraction process from callus in Dimocarpus longan Lour by ultrasound-assisted extraction using response surface methodology(响应面试验优化超声波辅助提取龙眼愈伤组织中单宁的工艺)

open access: yesZhejiang Daxue xuebao. Lixue ban, 2019
为提高龙眼愈伤组织中单宁的提取率,采用超声波辅助浸提法,基于乙醇浓度(A)、超声波功率(B)与提取时间(C) 3 个单因素试验,通过响应面试验优化设计,建立了龙眼愈伤组织单宁提取工艺。研究结果表明,龙眼愈伤组织中单宁的最佳提取条件为乙醇浓度61%、超声波功率140 W,提取时间54 min,提取温度 60 ℃,在此工艺条件下,提取量为7.53 mg · g-1。
LIUShengcai(刘生财)   +4 more
doaj   +1 more source

Study on extraction process of active ingredients with hypouricuria effect from Plantaginis Herba(车前草降血尿酸有效成分提取工艺的研究)

open access: yesZhejiang Daxue xuebao. Lixue ban, 2010
建立小鼠急性高尿酸血症模型,通过灌胃给药考察车前草的降血尿酸作用.采用正交试验设计,以车前草所含大车前苷为指标,考察乙醇浓度、提取时间、提取次数和乙醇用量4种因素对提取结果的影响.大车前苷和血尿酸的含量均用HPLC法测定.结果表明,车前草醇提组的小鼠血清尿酸水平明显低于模型组 ...
QIANYing(钱莺)   +3 more
doaj   +1 more source

低共熔溶剂提取油茶籽壳中原花青素的工艺优化Optimization of extraction of procyanidins from oil-tea camellia seed shell with deep eutectic solvents

open access: yesZhongguo youzhi, 2023
为促进油茶籽副产物的高值化利用,采用低共熔溶剂提取油茶籽壳中的原花青素,通过单因素试验考察了提取溶剂种类、摄取溶剂质量分数、料液比、提取温度和提取时间对原花青素得率的影响,并利用正交试验对油茶籽壳中原花青素提取的工艺条件进行优化。结果表明:低共熔溶剂提取油茶籽壳中原花青素的最优工艺条件为以氯化胆碱-柠檬酸(物质的量比1∶ 1)溶液为提取溶剂、氯化胆碱-柠檬酸溶液质量分数80%、料液比1∶ 25、提取温度80 ℃、提取时间40 min,在此条件下原花青素得率为5.26%。综上 ...
侯黔灵1,范丽美2 HOU Qianling1,FAN Limei2
doaj   +1 more source

分光光度法测定油茶籽油中总三萜含量的 前处理方法研究

open access: yesZhongguo youzhi, 2023
为准确定量油茶籽油中三萜类物质,对分光光度法测定油茶籽油中总三萜含量的样品前处理方法进行研究。通过单因素试验和正交试验考察了乙醇体积分数、提取温度、提取时间和提取次数对油茶籽油中总三萜含量的影响。结果表明:各因素对油茶籽油中总三萜提取的影响程度从大到小依次为乙醇体积分数>提取次数>提取温度=提取时间;油茶籽油中总三萜的最佳提取工艺条件为乙醇体积分数80%、提取温度80 ℃、提取时间40 min、提取次数4次,在此条件下提取测得油茶籽油中总三萜含量为(0.78±0.06)%(以齐墩果酸计)。综上 ...
叶美金1,2,杨玉敏3,冯鸿1,2,姜虹宇1,2,何咨霆1,邱宇帆1 YE Meijin1,2, YANG Yumin3, FENG Hong1,2, JIANG Hongyu1,2, HE Ziting1, QIU Yufan1
doaj   +1 more source

羟基酪醇对滇山茶油氧化稳定性的影响Effect of hydroxytyrosol on oxidative stability of Camellia reticulata seed oil

open access: yesZhongguo youzhi
羟基酪醇为化妆品新原料,为促进其在提高化妆品油脂稳定性、改善气味方面的应用,分别向滇山茶油中添加0.001%、0.005%、0.01%的羟基酪醇(以山茶油质量计),并以相同添加量的合成抗氧化剂叔丁基对苯二酚(TBHQ)作为阳性对照,通过Rancimat法和Schaal烘箱法对其进行加速氧化实验,以氧化稳定性指数(OSI)、过氧化值、酸值、p-茴香胺值以及关键性挥发性气味物质作为考察指标,分析羟基酪醇对滇山茶油氧化稳定性的影响。结果表明:与空白组相比,羟基酪醇添加量为0.005%和0.01 ...
朱金蒙1,2, 邱滟茹1,2, 卞燕南1,2 ZHU Jinmeng1,2, QIU Yanru1,2, BIAN Yannan1,2
doaj   +1 more source

Optimization of Microwave-assisted Extraction Process for Total Flavonoid from Tartary Buckwheat Flour(微波辅助双水相提取苦荞麦粉中黄酮类化合物) [PDF]

open access: yesShipin kexue jishu xuebao, 2014
Flavonoids were extracted from buckwheat powder by the microwave-assisted ethanol-ammonium sulfate aqueous two-phase system. The optimal extraction system of flavonoids from tartary buckwheat powder was determined through single factor experiments and ...
XU Chunming(徐春明)   +4 more
doaj   +1 more source

结合纹理和形态学特征的高分遥感影像建筑物震害信息提取

open access: yesDizhen xuebao, 2019
为提高震害信息获取时效性,对基于我国国产高分遥感影像的建筑物震害信息提取方法进行深入研究,本文以2017年5月11日新疆塔县MS5.5地震为例,利用该地震前后极灾区高分遥感影像,利用结合纹理和形态学特征的方法进行了建筑物震害信息提取,通过变化检测分析获取了极灾区建筑物震害信息,并与基于像元级和基于目标级的信息提取结果进行对比,采用震后无人机影像目视解译结果对本文结果进行了精度验证。结果表明:通过缩减研究区范围可大力提高数据提取精度和速度;运用灰度共生矩阵、二值化、数学形态学等方法对影像进行迭代运算 ...
Jinxiang Li   +4 more
doaj   +1 more source

Human–wildlife conflict and farmland transfer under informal land institutions: Evidence from rural China

open access: yesPeople and Nature, EarlyView.
Abstract Human–wildlife conflict (HWC) affects not only agricultural production but also how farming households adjust access to and use of land. Existing research has focused largely on welfare losses and land‐use responses, while little is known about whether ecological risk is associated with the governance arrangements through which farmland is ...
Xinrui Wang, Xian Liang, Bo Zhai, Yi Xie
wiley   +1 more source

电感耦合等离子体质谱法测定蛋黄卵磷脂中15种金属元素Determination of 15 kinds of metal elements in egg yolk lecithin by inductively coupled plasma mass spectrometry

open access: yesZhongguo youzhi, 2022
蛋黄卵磷脂样品经微波消解,采用电感耦合等离子体质谱法测定样品中15种金属元素含量,对检测条件进行了优化,并进行了方法学考察。结果表明,在射频功率1.55 kW、载气(高纯氩气)流速 1.03 L/min、等离子气体流速15.0 L/min、蠕动泵转速 0.1 r/s、采样深度 10 mm、重复次数 3 次条件下,通过在线加入内标钪(Sc)、锗(Ge)、铟(In)、铼(Re)元素可校正基体效应和干扰,测定汞元素时,加入金元素可降低测定误差;该方法的15 种金属元素线性关系良好,线性相关系数(R)均大于0 ...
陈秋玲,祝芷琦,李咏华,王小妹,梁北梅,温恺嘉,许一靖,曾还雄,林元亨,唐顺之 CHEN Qiuling, ZHU Zhiqi, LI Yonghua,WANG Xiaomei,LIANG Beimei, WEN Kaijia,XU Yijing,ZENG Huanxiong,LIN Yuanheng,TANG Shunzhi
doaj   +1 more source

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