Spectral Characteristics of Chemically Weathered Sandstones in the Yungang Grottoes,China

ABSTRACT

Many of the sandstones at cultural heritage sites around the world are susceptible to chemical weathering, and long-term monitoring of the chemical weathering would be of great value for heritage conservation and would also provide reference data for environmental protection policies and projects. Reflectance spectroscopy is a potential tool for monitoring sandstone weathering due to its non-destructive characteristics. In this paper, we present the results of an investigation into the reflectance spectra of sandstones at the Yungang Grottoes, China, where the sandstones are variously fresh, calcite-dissolved, or argillitic-altered. We found several spectral absorptions, including those at 490, 675, 900, 1410, 1918, 2205, 2330, 2350, and 2380?nm. The absorptions at 490, 675, and 900?nm are related to hematite cement, while that at 2330?nm is associated with calcite cement. The absorptions at 1410, 2205, 2350, and 2380?nm are induced by the Al–OH vibration of kaolinite, and that at 1918?nm is related to crystal water. The calcite-dissolved sandstones have lower absorption intensities at 2330?nm than fresh sandstones, and the argillitic-altered sandstones have lower absorption intensities at 490, 675, and 900?nm than the fresh sandstones. In the 1st-derivative reflectance plots, the absorption peaks at ～1400?nm shift towards shorter wavelengths with increasing kaolinite contents. The spectral features of the fresh, calcite-dissolved, and argillitic-altered sandstones are all different, and this means they can be distinguished spectroscopically, which demonstrates the usefulness of reflectance spectroscopy for the long-term monitoring of sandstone weathering in the Yungang Grottoes.     

农村土地纠纷案件的实证分析与对策研究

农村土地问题是农村社会矛盾和冲突的总根源,已成为当前影响农村社会稳定和发展的首要问题。文章在对农村土地纠纷深入调研的基础上,分析了农村土地纠纷案件的主要特点和成因,并进一步提出了解决农村土地纠纷的对策。     

说put道“放”———汉英动词词汇化对比一例

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论油画笔触的嬗变与审美特征

笔触作为绘画形式语言,它承载色彩,塑造形象,是展现画家个性、气质、修养、内涵最直接的反映。界定概念和说明笔触在东西方油画艺术领域的发展演变是研究笔触独立审美价值的基础。笔触的审美特征具体表现为风格美、力度美、肌理美和精神美等。通过分析笔触发展嬗变与时代审美,及其艺术发展的自律性特征,研究笔触的价值和意义将促进油画语言的本体回归,兑现出笔触独立的审美内涵。     

略论我国古代政治辞说的艺术技巧

本文以中国传统政治文化的典型史实为题材,借助逻辑学、语言学、写作学、社会学、政治学等理论成果,来总结和论证我国古代政治辞说的艺术技巧.文章从政治辞说的理论根基入手,探讨逻辑论辩在政治辞说中的基础作用,并以古代公文的写作范式为例具体分析政治辞说的写作技巧,以社会禁忌的广泛存在进一步透视在政治辞说运作中容易被忽视的避讳技巧.     

一类具偏差变元的高维周期系统的周期解

探研下面具偏差变元的高维周期系统的周期解的存在性、唯一性、稳定性等问题。这里，是n阶实连续的函数方阵，且，(为常数)。是上的n维连续函数，且对任意的，，r为实参数，利用指数型二分性和不动点方法，推广了文[1]的主要结果。     

由算子定义的解析函数的辐角估计

通过Hadamard卷积定义了算子变换,利用其得到了单位开圆内解析函数类的新子类并研究了新函数类的辐角估计性质.     

浅谈新闻评论中论据的运用艺术

新闻评论中的论据占的比重最大,起到的作用也相当重要,所以要想写好新闻评论就必须研究新闻评论论据的运用艺术,它是打牢新闻评论写作基础的关键。     

The impact of varying argument quality and minority size on influencing the majority and perceptions of the minority

Past minority influence research has found that the number of minority subgroup members and argument quality can affect the likelihood of the minority subgroup being able to influence the majority subgroup. How minority size and argument quality affect minority influence and perceptions of the minority is addressed in this study. Confederates were used to vary argument quality and the size of the minority subgroup while keeping consistency of presenting the minority's side of the issue constant. Groups discussed a topic and measures were used to assess the amount of influence, perceived competence, perceived correctness, and how much the minority was liked. Results indicated that both argument quality and minority size were important when attempting to influence the majority and a large minority can compensate for a minority using weak arguments while a small minority using weak arguments residts in strengthening the majority's initial opinion. The perceptions fostered by the minority were a function of an argument quality by group size interaction.     

A Note from the New Editors

This article develops a multimodal model for how claims and evidence work across linguistic, numeric, and visual modes in the professional writing of environmental scientists. I coded and analyzed two reports (Bacey &; Barry, 2008 Bacey , J. , &; Barry , T. ( 2008 ). A comparison study of the proper use of Hester-Dendy® samplers to achieve maximum diversity and population size of benthic macroinvertebrates Sacramento Valley, California (Report No. EH08-2) . Sarcramento , CA : California Environmental Protection Agency . [Google Scholar]; Levine et al., 2005 Levine , J. , Kim , D. , Goh , K. S. , Ganapathy , C. , Hsu , J. , Feng , H. , &; Lee , P. ( 2005 ). Surface and ground water monitoring of pesticides used in the Red Imported Fire Ant Control Program (Report EH05-02) . Sacramento , CA : California Environmental Protection Agency . [Google Scholar]) written by research scientists working for California's Department of Pesticide Regulation (DPR) by applying concepts from studies of argument, genre, and visual representations in science. The claim-evidence patterns show initial and summative claims as well as warrants being presented in linguistic forms; however, supporting evidence (i.e., data and backing) is found in numeric, visual, and linguistic forms. These findings highlight the need to extend Toulmin's understanding of claim-evidence relationships into a more robust multimodal model.