共查询到19条相似文献，搜索用时 265 毫秒
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沙棘籽原花青素提取单因素实验研究 总被引：1，自引：0，他引：1
以沙棘籽为原料，考察了脱脂方式、提取温度、提取时间、乙醇浓度、料液比、提取次数等6个因素对原花青素提取率的影响。结果表明，超临界CO2萃取沙棘籽油后籽渣中原花青素含量要高于溶剂脱脂；从30℃至70℃原花青素提取率随温度升高而降低，但降低幅度不大，从70℃-90℃，提取率又略有升高；原花青素提取率随提取时间、提取次数、料液比的增加而增加，当提取时间、提取次数、料液比增加到一定程度后，原花青素提取率增加的不多或者基本不再增加；乙醇浓度以70％的乙醇溶液提取效果最好。 相似文献
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《西部林业科学》2017,(5)
以地热河谷地区的薏苡仁为研究对象,提取薏苡仁油并进行抗肿瘤活性测定,目的是为提高薏苡仁油的得率,为工业化提取薏苡仁油提供参考。以提取时间(30-50min)、提取温度(40-60℃)、料液比(1︰2.5-1︰4.5m/v)和超声功率(100-140W)为因素,采用L9(34)正交试验优化了最佳工艺,并进一步进行薏苡仁油对肿瘤细胞的抑制活性研究。结果表明,上述4个因素对高良乡薏苡仁油提取率均有一定的影响,提取时间、提取温度、料液比和超声功率对薏苡仁油提取率的贡献率分别是74.47%、16.53%、5.11%和2.83%,并通过直观分析和方差分析,得知薏苡仁油的最佳提取工艺为以无水乙醇为溶剂,料液比1︰2.5m/v、提取温度60℃、提取时间50min、超声功率100W,在此提取条件下薏苡仁油的提取率为7.68±0.12%,采用该提取工艺得到的薏苡仁油对结肠癌细胞(SW480)、人乳腺癌细胞(MCF7)、人肝癌细胞(SMMC7721)、人肺癌细胞(A549)、人早幼粒白血病细胞(HL-60)5种肿瘤细胞的抑制率分别为95.52%、85.02%、91.83%、92.54%、72.89%。该研究结果为将薏苡仁油开发成抗肿瘤保健植物油奠定理论基础。 相似文献
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超声法提取薏苡仁油的工艺研究 总被引：1，自引：0，他引：1
采用超声波法提取薏苡仁油,对其中的影响因素提取溶剂、药材粒径、提取时间、提取温度、料液比等进行系统研究。结果表明：将薏苡仁药材粉碎至粒径60目,按料液比1∶3．5加入无水乙醇为提取溶剂,在60℃温度下提取40 min ,所得提取率最高为11．8％。该提取工艺具有提取时间短,效率高,节省溶剂的特点。 相似文献
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溶剂法萃取漆油的工艺研究 总被引：1，自引：0，他引：1
研究了漆油溶剂萃取法中提取温度、时间和漆籽仁过筛情况等对漆油萃取得率的影响,正交试验得出漆油的较优萃取工艺条件.结果表明:随着提取温度的升高萃取得率增大,但在52～57℃之间增幅较小;随着萃取时间的增加萃取得率增大,超过120min后萃取得率的增加趋势不明显;过0.5 mm筛较优;漆油的较优萃取工艺条件为:过0.5 mm筛,提取温度为57 C,提取时间为120min;该条件下,漆油的萃取得率为26.53%.优选的工艺稳定可行.能为漆油的生产、开发与利用提供试验依据. 相似文献
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为加快对马尾松松花粉多糖的开发利用,探究提取多糖的最佳工艺组合。试验以贵阳成熟马尾松林松花粉为研究对象,采用超声破壁技术及苯酚-硫酸法测定多糖含量,通过探究料液比、提取时间、提取温度、提取次数4个不同因素对马尾松松花粉多糖提取率的影响,并结合单因素和正交试验,得出松花粉多糖的最佳提取条件。结果表明:提取次数对马尾松松花粉多糖提取量的影响最大,其次为料液比和温度,二者对多糖提取量的影响相差不大,提取时间对多糖提取量的影响最小;马尾松松花粉多糖最佳的提取工艺组合为料液比1∶10(g∶m L)、提取时间2.0 h、提取温度85℃、提取3次,提取率为11.246 3 mg/g。因此,通过此工艺组合,可提高松花粉多糖的提取率,对马尾松松花粉的开发利用具有重要意义。 相似文献
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《Forest Ecology and Management》2007,238(1-3):81-91
Empirical relationships to predict the leaching flux of dissolved inorganic nitrogen in forested ecosystems as a function of N-deposition and stand and site characteristics have been derived using an updated version of the UN-ECE/EC intensive monitoring database, including data for the period up to the year 2000. These relationships were validated on an independent database with literature data. For the model development, reliable N budgets were available for 57 forest sites in Europe for a median period of 5 years. Multiple regression analysis showed that the measured N leaching fluxes could be well explained by a number of different empirical relationships. The simplest model included only the N throughfall flux and explained 30% of the variance in observed leaching fluxes. The most complex model showed a positive relationship between N leaching fluxes and N throughfall flux, temperature and the pH of the mineral topsoil and a negative relationship with the C/N ratio of the organic layer. This relationship explained 42% of the observed variance in leaching fluxes.The empirical equations explained 47–64% of the observed variation in leaching flux in an independent validation database. The best relationships were the one that included only N throughfall as a predictor, and a relationship that also included the C/N ratio of the organic layer as a factor to express differences in reaction above or below a critical C/N ratio. The median error was 211 mol/(ha year) for the relationship with N throughfall and 240 mol/(ha year) for the relationship that also included the C/N ratio. The median relative errors were 70 and 50%, respectively, for the two relationships. These large errors are mainly due to a general overestimation of N leaching fluxes at sites with a nitrogen-leaching fraction below 0.3. These are primarily Nordic sites with low total N-deposition levels and mid-latitude sites with relatively high C/N ratios. 相似文献
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为探求不同光照和温度对杉木种子萌发的影响,该研究以杉木(Cunninghamia lanceolata)种子为试验对象,设置红光、蓝光、白光3个光照处理条件,每个光照处理条件设0,5,20μmol/(m2·s)3个光量梯度,并测量了萌发率、萌发指数和发芽势.结果表明:白光5μmol/(m2·s)、红光20μmol/(m... 相似文献
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The soil CO2 evolution rate was measured in a virgin Korean pine forest. The results in June showed that the lowest value of evolution
rate was 220 mg/(m2·h) and appeared at 6:00 a.m. The highest value was 460 mg/(m2·h) at 18:00. The rates of CO2 evolution were related with soil temperature. On the basis of the constructed regression equation and the monthly average
values of temperature, the magnitude of CO2 evolution from Korean pine forest soil was 10.4 t/hm2 during a growing season.
This project was funded by the Opened Research Station of Changbai Mountain Forest Ecosystem, Chinese Academy of Sciences.
Responsible editor: Zhu Hong 相似文献
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根据５ａ定位观测，对尖峰岭热带山地雨林更新林生态系统的水文化学循环规律的数据分析表明，年均降雨量为２６６８．３ｍｍ，其中总径流量占４６．７％，蒸散量５３．３％，冠层截留量１４．０％。Ｎ、Ｐ、Ｋ、Ｃａ、Ｍｇ的年均降雨输入量为７８．４ｋｇ／（ｈｍ２·ａ），总径流输出５６．７ｋｇ／（ｈｍ２·ａ），净积累２１．６ｋｇ／（ｈｍ２·ａ）；Ｓｉ、有机Ｃ、Ａｌ、Ｍｎ的年均降雨输入量为２５．０ｋｇ／（ｈｍ２·ａ），总径流输出为１１２．３ｋｇ／（ｈｍ２·ａ），净损失８７．３ｋｇ／（ｈｍ２·ａ），更新林系统仅处于更新进展过程中，同时证实了冠层对降水化学的淋溶效应，净淋溶系数达４．１１；提出了降雨、林内净降雨、总径流的各水化学物含量与其相应水量的回归模式 相似文献
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根据５ａ定位观测，对尖峰岭热带山地雨林更新林生态系统的水文化学循环规律数据分析表明，年均降雨量为２６６８．３ｍｍ，其中总径流量占４６．７％，蒸散量５３．３％，冠层留量１４．０％。Ｎ、Ｐ、Ｋ、Ｃａ、Ｍｇ的年均降雨输入量为７８．４ｋｇ（ｈｍ＾２．ａ），总径流输出５６．７ｋｇ／（ｈｍ＾２．ａ），净积累２１．６ｋｇ／（ｈｇｍ＾２．ａ），Ｓｉ，有机Ｃ、Ａｌ、Ｍｎ的年均降雨输入量为２５．０ｋｇ（ｈｍ＾２．ａ） 相似文献
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Red pine (Pinus resinosia Ait) and southern pine (Pinus spp.) sapwood blocks were pressure treated with CCA-C at retention of 6.4, 2.0, 1.5 kg?m-3 followed by fixation using 11 post-treatment schedules ranging from 50-70 °C and 5 different relative humidity conditions. The effect of these post-treatment schedules on fixation rate, chemical leachability and decay resistant once were evaluated to better understand the effects of fixation/drying conditions on leachability and biodeterioration. Southern pine blocks fixes slightly slower than red pine. Fixation of CCA at high temperature high humidity, essential initially fixation at high humidity for fixation/drying schedules, resulted in lower leaching of chromium and arsenic elements than high temperature low humidity or initially fixation at the high temperature low humidity conditions. Copper leaching was indicated no significant difference under 11 fixation/drying conditions for both species. Weight losses for southern pine by Chaetomium globosum was lower than red pine by Gloeophyllom trabeum. There were some different capacities of decay resistance for both species under those post treatment conditions. 相似文献
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两种提取红松种子蛋白质的工艺方法比较研究 总被引：1，自引：0，他引：1
为寻找新的植物蛋白资源,研究发现,红松种子中蛋白质含量在13％～20％,具有明显的生理活性,是一种新的具有活性的植物蛋白质资源。以脱脂红松种子粉为原料,比较PBS-NaCl缓冲液盐溶法和NaOH碱溶法提取红松种子蛋白质工艺。分别通过单因素和正交试验,确定最佳的提取工艺：研究了料液比、提取温度、提取时间、溶液浓度对蛋白质提取率的影响,并进行了L9（4^5）的正交试验,并测定了两种工艺得到的红松种子蛋白的等电点。PBS-NaCl缓冲液盐溶法得到的红松种子蛋白等电点pI=3．7,碱溶法提取蛋白的等电点pI=4．0。PBS-NaCl缓冲液盐溶法提取红松种子蛋白质的提取工艺：在温度30℃水浴环境下,以0．12mol／LPBS-NaCl缓冲液盐溶液提取,按1：25的料液比搅拌浸提150min,蛋白提取率达到62．86％。碱溶法提取红松种子蛋白质的最佳工艺参数是以0．0005mol／LNaOH溶液,按1：30料液比,在45℃条件下低速搅拌浸提60min,此时蛋白的提取率为72．07％。结论：从蛋白质提取率的角度考虑,碱溶法优于PBS-NaCl缓冲液盐溶法;从蛋白质稳定性和提取率两方面考虑,PBS-NaCl缓冲液盐溶法优于碱溶法。 相似文献