共查询到10条相似文献，搜索用时 93 毫秒
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采用分段浸取新工艺是黑荆树皮单宁提取的关键技术。即以平转型连续最提为常压段、以水平渗滤（进、出）垂直釜为加压段，经生产考核，其工艺先进、运行可靠、经济合理、操作简便，产品质量稳定。 相似文献
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Chamaedorea palm frond (xate) certification has been broadly promoted throughout Mesoamerica as a means to foster the integration of
forest conservation and economic development. This study examined the feasibility of xate commercialization and certification
at the scale of the extractor livelihood system in an ejido in the Chinantla region of Oaxaca, Mexico. Ethnographic methods
were used to collect livelihood system data. These data were used to develop an ethnographic linear program (ELP) model of
extractor households to analyze the effects of palm frond management and marketing scenarios on their livelihoods. Three necessary
conditions for the feasibility of certification were hypothesized: two related to extractor livelihoods and another related
to market fluidity. Livelihood outcomes supported the notion that resource sustainability and economic development are not
mutually exclusive, and provided support for xate certification as an intervention oriented toward the integration of these
objectives. In contrast, the model revealed an unfavorable discrepancy between xate supply and the level of demand expressed
by an interested buyer. This shortfall represented a substantial obstacle to the feasibility of xate certification in the
community. Low demand fulfillment suggested that xate certification ultimately represents an infeasible strategy for the community,
irrespective of the observed livelihood and conservation benefits. Results highlighted the importance of understanding household
objectives and market context in local decisions to pursue NTFP certification. We suggest that the community’s objectives
would best be served by engaging neighboring communities in a cooperative and controlled effort to augment regional supply. 相似文献
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用挥发油提取器提取马尾松土贡种源松针中挥发油,利用气相色谱-质谱（GC-MS）分析其中的化学成分,采用GC峰面积归一化法定量,并与马尾松普通种源松针油做对比。结果表明,土贡种源和普通种源挥发油得油率分别为0.52％、0.60％,各分出69、75个成分,鉴定其中23个,分别占挥发油总量的92.65％、94.56％,其挥发油主要成分为α-蒎烯（37.673％、46.715％）、莰烯（3.724％、3.015％）、β-蒎烯（14.969％、12.978％）、石竹烯（8.242％、10.212％）,除α-蒎烯含量相差9.042％以外,其他成分含量相差不大。 相似文献
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目的:研究石榴花挥发油的化学成分及β-葡萄糖苷酶对其的增香作用。方法:使用挥发油提取器提取石榴花的挥发油,以GC-MS法进行分析鉴定,用面积归一化法获得各化合物的相对含量。结果:分别从无酶和有酶的石榴花挥发油提取物中确证了42个化合物。证明β-葡萄糖苷酶可以增加石榴花中某些香精成分的相对含量,但也使其中某些成分的相对含量减少。结论:石榴花中的化学成分十分丰富,GC-MS可以对石榴花挥发油进行良好的分离鉴定,同时证明β-葡萄糖苷酶对石榴花的增香作用不显著。 相似文献
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目的:建立夹竹桃花挥发油GC-MS的色谱分离鉴定方法,分析夹竹桃花挥发油的化学成分和对豚鼠离体子宫平滑肌的作用。方法:采用挥发油提取器提取夹竹桃花挥发油,以GC-MS法进行分析鉴定,建立了豚鼠离体子宫模型。结果:分别从无酶和有酶的夹竹桃花挥发油提取物中确证了58和57个化合物,挥发油对豚鼠离体子宫平滑肌有收缩作用。结论:对夹竹桃的挥发油化学成分进行了比较分析结果表明,β-葡萄糖苷酶对夹竹桃花有较弱增香作用,也能增加豚鼠离体子宫平滑肌收缩。 相似文献
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Extracts are important components of fuels.Fatty-extracts with high heating value(HV) are hypothesized by researchers as positively related to the HV of fuels.The Soxhlet extractor is typically used to extract fatty-extracts but it has shortcomings,including long processing time(8–10 h) and the requirement for large amounts of organic solvent.Supercritical extraction is an alternate and useful technique for extraction of natural products.However,published studies rarely discuss the relationship between extracts and HV.In this study,we assessed the supercritical extracts(Su E) of forest fuels in the Great Xing'an Mountains.Our results indicated that the optimum conditions for extraction of Su Es were40–60 mesh,40–50 MPa,45 °C,80 min and a CO_2 flow rate of 1.5–2.0 dm~3/min.The Soxhlet extracts contents and the Su E contents were all related to HV.However,R~2 of the coniferous samples(0.8499) and needle samples(0.9722) demonstrated that the correlation between HV and the Su E content was closer.We conclude that supercritical fatty-extracts provide a useful index of the HV of fuels,especially coniferous fuels.Su E data can be used in fire management,for example to estimate the rate of fire spread or fire intensity. 相似文献