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张小丽 《广东海洋大学学报》1997,(2)
研究了珍珠加工中前处理方法、作用和效果．在前处理过程中，珍珠内有荧光物质、长碳链饱和脂肪酸（脂）等物溶出。珍珠的颜色不同、前处理工艺方法不同．溶出物质也不同．经过前处理，珍珠的光泽明显增加；漂白速度有所加快。可通过测溶液折射率变化的方法来比较前处理工艺中有机溶剂的处理效果。 相似文献
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The prerequisite for obtaining variations of terrigenous grain-size of marine sediments is how to effectively remove non-terrigenous matters and preserve terrigenous particles synchronously. Combined with observations under biological microscope and scanning electron microscope, a comparative study of biogenic debris removal effect and terrigenous grain-size analysis under different pretreatment condition was performed on core sediments, which were retrieved in the South China Sea during the MD190 cruise. Our new results showed that the main three biogenic particles, namely, organic matter, carbonate, and opal in marine sediments could be removed effectively by 30% H2O2 in a stirring water bath at 60 ℃ for 3 h, 0.5% HCl for 1 h, and 2 mol/L Na2CO3 in a stirring water bath at 85 ℃ for 5 h, in turn. Such pretreatments achieved the goals of biogenic debris removal efficiency and relatively well-preserved terrigenous particles. Prior to selecting an appropriate pretreatment method, this study suggested that the actual effects of biogenic detritus on grain-size results of diverse marine sediment samples should be taken into account. If the laboratory data are ensured to be closer to the natural grain-size distribution of terrigenous particles, the removals of all biogenic debris are not always needed, and the less pretreatment processes the better. For example, opal particles have little effect on terrigenous grain-size distribution when their percentage is lower than 2%. Thus, there is no use to remove them from marine sediments before laboratory grain-size analysis of terrigenous particles. Additionally, ultrasonic is not suggested through the whole process of terrigenous grain-size analysis because the strong energy of ultrasonic can lead to the fragmentation of some fragile terrigenous particles. 相似文献
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为了探讨生物硅对沉积物粒度测量结果的影响, 本文采用两种不同前处理方法对普里兹湾重力柱状样品进行了粒度测试。结果表明, 生物硅对沉积物的平均粒径以及黏土、粉砂、砂组分的影响较小, 而对沉积物的分选、偏态、峰态以及粒度频率分布的影响较显著。结合两组粒度组分相关性分析以及各粒级含量累积减小值, 认为生物硅对沉积物中砂、粉砂、黏土级组分含量的影响逐渐减小, 这也造成未去除生物硅的沉积物粒度测量结果偏粗。另外, 通过对比发现普里兹湾沉积物中生物硅粒径主要分布在<3Φ、5.25Φ—7.25Φ、8.75Φ—9.75Φ的粒径范围。极地研究中, 沉积物粒度结果为重建古环境变化提供重要参考, 本文研究认为在普里兹湾海域沉积物粒度研究中去除生物硅对研究结果有积极作用。 相似文献
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环境样品中有机物分析的前处理技术 总被引：4，自引：0，他引：4
综述了顶空法、吹脱－捕集法、固相萃取、微波萃取、超临界流体萃取技术在环境样品前处理中的应用现状并比较了这种几样品处理方法的优缺点。 相似文献
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前处理方法对北黄海沉积物粒度的影响 总被引：31，自引：1，他引：31
采用不同方法对北黄海底质样品进行了粒度分析前处理，以探讨有机质和碳酸盐对北黄海沉积物粒度的影响。结果表明，去除有机质或碳酸盐后，粗粒沉积物（呈双峰分布）粒度分布的峰态明显变宽，平均粒和戏及粗颗粒（＞32μm）组分含量明显增加；而细粒沉积物的粒度分布发生明显细偏，表现为众数的细化及平均粒径和粗颗粒含量的降低。北黄海底质沉积物的有机碳含量变化与沉积物的平均粒径呈明显的负相关，暗示了浅海沉积物中有机碳的输运和积聚主要是伴随着细颗粒组分发生；而碳酸盐含量同沉积物粒度的关系不甚明确，可能与沉积物物源的关系更为密切。 相似文献
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Arthur Raj Binupriya Muthuswamy Sathishkumar Dhamodaran Kavitha Krishnaswamy Swaminathan Sei‐Eok Yun Sung‐Phil Mun 《洁净——土壤、空气、水》2007,35(2):143-150
Batch biosorption experiments were carried out for the removal of Congo red from aqueous solution using native and pretreated mycelial pellets/biomass of Trametes versicolor. The effect of process parameters such as contact time, dye concentration, and pH on the extent of Congo red biosorption has been investigated. Higher dye concentrations resulted in lower biosorption. Increases in biomass dosage led to increases in the levels of biosorption. Biosorption kinetics and equilibrium data are essential basic requirements to develop an effective and accurate design model for the removal of the dye. A kinetic study showed that the biosorption of the dye on fungal biomass was a gradual process. Pseudo‐first‐order, pseudo‐second‐order, and Bangham's model were used to fit the experimental data. The results of the kinetic studies showed that the second‐order kinetic model fitted well for the present experimental data. Equilibrium isotherms were analyzed by Langmuir, Freundlich, Dubnin‐Radushkevich, and Temkin isotherms. The biosorption equilibrium data obeyed the Langmuir and Temkin isotherms well. Acidic pH was favorable for the biosorption of the dye. Studies on the pH effect and desorption show that chemisorption seems to play a major role in the biosorption process. Among the native and pretreated biomass studied, autoclaved biomass showed a better biosorption capacity. 相似文献
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青海省地磁FHD质子矢量磁力仪观测已投入运行3年有余,为了提高地磁FHD质子磁力仪观测质量,通过对西宁、德令哈、都兰、湟源、大武5个地震台FHD仪动态变化曲线的分析,给出合理的预处理方法与技巧。 相似文献
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