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WAN Mengfei LIU Zhongdong CHEN Yongfu LU Caiyuan LI Kechang WANG Fahe WANG Xiaomei LIU Boxiang 《海洋湖沼学报（英文）》2019,(3):892-897
Octenylsuccinate starch ester,also called pure gum,is non-toxic and odourless modified starch which is widely used in many food fields.This study synthesized pure gum in a reaction kettle using the low molecular weight trehalose and octenyl succinic acid.An orthogonal test was carried out to find how the reaction factors aff ect the synthetization of octenylsuccinic acid polysaccharide ester and to optimize the reaction at single factor level.The optimal products were obtained using 1:2 of octenylsuccinic acid:alginic acid,catalysed by 0.1% p-toluenesulfonic acid catalyst for 1.5h at 200℃ under vacuum conditions.The gained product contains up to 46%of seaweed gel monoesters.The degree of esterification of the polysaccharide is controlled by the use of the small-molecule trehalose.Compared with the traditional methods,our process can reduce raw material cost and improve emulsification stability of pure gum.These all can significantly improve the market competitiveness of pure gum products. 相似文献
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Vegetation sampling is an effective mineral exploration technique in areas of transported cover in the Tanami Gold Province where other techniques have been of limited success. This research tests the ability of plants to show signatures of mineralisation as well as the optimum scale of sampling for first-pass mineral exploration surveys. The semi-arid Tanami Gold Province in northern Australia encompasses nearly 160,000 km2 and is a highly prospective yet under-explored region due to transported cover masking mineralisation. Various dominant plant species were sampled along transects across four sites of Au mineralisation in the Tanami (Larranganni, Hyperion, Coyote and Titania). Snappy gum (Eucalyptus brevifolia) gave a geobotanical (plant distribution) and lithological (S and Zn) signature of an underlying geological structure known to host Au mineralisation at the Coyote Prospect. Soft spinifex (Triodia pungens) provided an Au, As, ± Zn, ± S, and ± Ce expression of buried Au mineralisation at Coyote and Titania. At the Hyperion prospect, mineralisation is located at the contact between granite and dolerite, and biogeochemical signatures from snappy gum and dogwood (Acacia coriacea) show elevated ± Au, Ce, S and Zn that corresponded to the contact. Biogeochemistry is able to determine the location of mineralisation at each site, except at Hyperion where the sample density was too low. It is able to identify underlying substrate differences, however, background knowledge relating to regolith, geology, hydrology and geophysics are important in aiding the interpretation of the elemental data. It was found that having too few samples (at Hyperion) there was insufficient useful information for mineral exploration. Grid coverage of an area (at Titania) provided information on mineralisation and groundwater dispersion plumes; however, in this case a single transect over the same area would have been sufficient for a first-pass mineral exploration survey. 相似文献
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针对寨上金矿区钻探中存在的坍塌、缩径等钻孔护壁难题,在采用多种冲洗液无效的情况下,试验应用了植物胶低固相冲洗液,成功地解决了该矿区钻探钻孔护壁难题。分析了矿区钻探护壁困难的原因,介绍了冲洗液应用技术。 相似文献
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介绍了甘肃文县阳山矿区泡沫冲洗液和HJ-YS系列冲洗液的研制与应用。以42线ZK706孔和51线ZK3002、ZK3016、ZKN3084、ZK0204钻孔为例,首先介绍了泡沫冲洗液在孔壁失稳地层的应用效果;其次介绍了低固相植物胶HJ-YS系列冲洗液对破碎强烈、多溶洞、易漏失、水敏性强、采心困难的复杂地层所具有的良好的润滑减阻和护壁堵漏效果。 相似文献