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31.
Elemental carbon was extracted from sediments by chemical oxidation and identified by Raman spectroscopy. The experimental
results indicate that elemental carbon, defined by processing, is a continuum ranging from single crystal graphite to amorphous
carbon. Chemical oxidation is a feasible method to extract elemental carbon from sediments, and when experimental condition
and time are properly controlled, it can remove organic carbon without any loss of elemental carbon. However, due to the differences
in experimental conditions and methods, different results have been obtained. Therefore, we believe that the determination
of standard sample and its concentration as well as the unification of the experimental method are of great importance. Also,
the unification and definition of all these carbon particulates can facilitate transect comparison and further research in
related fields. In profile research, elemental carbon was extracted and determined by using the same method. The elemental
carbon curve tends to change with other climatic proxies, indicating elemental carbon can provide another new proxy for climatic
and environmental changes. Based on the analysis, we deduce that the elemental carbon record has different implications for
climate and environmental changes on different time-scales.
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Translated from Acta Sedimentologica Sinica, 2007, 25(5): 745–752 [译自: 沉积学报] 相似文献
32.
室内平面要素的准确提取与关系恢复是室内模型自动化语义重建的重要基础,本文提出了一种面向复杂三维点云的室内平面要素提取与优化方法。该方法首先利用区域增长和RANSAC平面混合分割方法分割室内点云数据;其次利用室内语义部件的空间位置信息及包围盒和法向量信息,对分割后的平面进行平面要素的精确提取;然后对提取的墙面进行优化,实现共享墙面的合并,解决室内墙面冗余的问题;最后利用门与墙的空间位置信息,恢复门墙关联关系。试验部分采用了两组试验数据：一组是深圳大学某层教学楼的激光点云数据,另一组是国际摄影测量与遥感学会（ISPRS）的标准数据,通过对试验结果进行评估,验证了本文方法的有效性和可靠性。 相似文献
33.
目的：观察芪连结肠宁治疗慢性复发型溃疡性结肠炎脾虚湿蕴证的临床疗效及其对炎症因子的影响。方法：将60 例慢性复发型溃疡性结肠炎脾虚湿蕴证患者采用随机数字表法分为治疗组和对照组,每组各30 例。对照组给予西医常规治疗,并配合饮食指导和心理健康宣教,治疗组在对照组的基础上加服芪连结肠宁汤治疗。治疗8周后比较2组治疗前后中医证候积分、溃疡性结肠炎改良梅奥（Mayo）积分,检测粪便钙卫蛋白（FC）浓度及血清白细胞介素-6（IL-6）、肿瘤坏死因子-α（TNF-α）水平,并观察不良反应。结果：中医证候总有效率治疗组为 93.33%（28/30）,对照组为83.33%（25/30）,2组比较,差异有统计学意义（P<0.05）。治疗后2组中医证候积分、Mayo积分、粪便FC浓度及血清IL-6、TNF-α水平均较治疗前下降,且治疗组下降幅度较对照组大,2组比较,差异均有统计学意义（P<0.05或P<0.01）。结论：芪连结肠宁可有效改善慢性复发型溃疡性结肠炎脾虚湿蕴证的临床症状,控制疾病活动性,降低粪便FC浓度及血清IL-6、TNF-α水平,值得临床推广应用。 相似文献