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中国科学院广州地球化学研究所在大气中萘的单体三元同位素（δ13C，Δ14C 和 δ2H）组成及其源解析取得新进展（图）
中国科学院广州地球化学研究所 大气 萘 单体三元同位素 δ13C Δ14C δ2H 中等挥发性有机物
2020/6/28
中等挥发性有机物（IVOCs）是一类重要的二次有机气溶胶（SOA）前体物，对SOA的贡献率可达30%~60%。萘，因其相对较高的含量和较高的SOA生成潜势，高频次地被选作为研究IVOCs的模型化合物。深入了解大气中萘的排放源组成，可以为进一步理解IVOCs的排放源组成特征提供参考依据，有助于制定针对性的空气污染防治政策。然而，目前大气中萘的排放源组成和相对贡献仍不够明晰。基于有机污染物的单体同位素...
δ18O and δ13C isotope investigation of the Late Glacial and early Holocene biogenic carbonates from the Lake Lednica sediments,western Poland
Stable isotopes δ18O and δ13C Late Glacial Early Holocene western Poland
2009/10/20
Stable isotope composition (δ18O and δ13C) of biogenic carbonates derived from the Lake Lednica sediments at Rybitwy, western Poland, was applied to obtain data on climatic changes during the Late Gla...
Reconstructions of the early and middle Holocene climate and environment based on δ13C and δ18O records in biogenic carbonates;Lake Niepruszewskie,western Poland
Biogenic carbonates Stable carbon and oxygen isotopes Lacustrine sediments palaeoclimate
2009/10/20
Apolinarska, K. 2009. Reconstructions of the early and middle Holocene climate and environment based on δ13C and δ18O records in biogenic carbonates; Lake Niepruszewskie, western Poland. Acta Geologic...
构造煤13C NMR 谱及其结构成分的应力效应
构造煤 应力效应
2009/3/19
运用NMR(CP/MAS+TOSS)方法, 获得了不同类型构造煤的13C NMR高分辨谱. 在此基础上, 进行谱的拟合和峰的解叠, 求出各种碳官能团的相对含量, 并结合Ro, max, XRD和元素分析成果, 进一步研究了不同类型构造煤结构及成分变化的应力效应. 结果表明: Ro, max不仅是反映煤级的重要指标, 而且也是反映构造煤结构应力效应的有效指标. 煤大分子基本结构单元堆砌度Lc以及La...
南京葫芦洞石笋δ13C对冰期气候的复杂响应与诊断
葫芦洞 石笋
2009/2/27
文中重建了南京葫芦洞内距今75~10 ka期间7支石笋δ13C的时间变化序列, δ13C曲线在重叠时段均具有一致性波动形式. 在最后一个冰期/间冰期旋回, δ13C值变化幅度达6‰, 反映了C3/C4植被类型变化对δ13C的主控作用. 然而, 在末次冰期格陵兰冰心记录的DO暖事件时(千年尺度), δ13C与指示降水变化的δ18O呈反相关, 主要反映了快速渗水条件下洞穴岩溶水对土壤CO2溶解量的降低...
重庆芙蓉洞洞穴沉积物δ13C、δ18O特征及意义
重庆芙蓉洞 洞穴沉积物 氧碳稳定同位素 平衡分馏
2010/8/17
利用重庆芙蓉洞内各种新老沉积物的δ13C、δ18O以及对洞穴内的滴水、池水和洞外泉水的长期观测结果，发现芙蓉洞内的次生沉积物中氧同位素变化整体一致，处于稳定温度下(16℃)的平衡分馏状态。而且洞内滴水和池水的氧同位素也相当一致，反映了外界大气降水中氧同位素的年平均状态。芙蓉洞内各种沉积物中碳同位素变化范围很大，从0‰~-11‰均有分布。由于芙蓉洞内各种滴水以及池水中溶解无机碳(DIC)的δ13C变...
选取位于黄土高原中部的甘肃西峰剖面作为研究对象, 分析了该剖面末次间冰期以来土壤有机碳和全岩碳酸盐的碳同位素组成变化. 该剖面的土壤有机碳同位素组成(δ13CSOM)变化范围为−23.8‰~−20.2‰, 间冰期偏高, 冰期偏低. 全岩碳酸盐的碳同位素组成(δ13CTC)变化范围为−8.5‰~−3.6‰, 但总体显示出与δ13CSOM值相反的变化趋势...
采用GasBench-IRMS气体质谱分析技术，实现了碳酸盐岩中碳氧同位素的在线连续分析。优化了色谱柱温、离子源参数等工作条件，排除了空气中N2O的干扰。结果表明，色谱柱柱温为40℃、65℃时，方法线性范围较宽，结果准确可靠。方法用于碳酸盐岩国家一级标准物质中δ^13C和δ^18O的测定，结果与标准值一致。
DOC cycling in a temperate estuary: A mass balance approach using natural 14C and 13C isotopes
DOC cycling temperate estuary A mass balance approach natural 14C 13C isotopes
2014/6/9
We measured dissolved organic carbon (DOC), dissolved inorganic carbon (DIC), and their corresponding del14C and del13C values in order to study the sources and fates of DOC in the York River Estuary ...
浙江煤山长兴阶有机碳δ^13C层序分布特征及古气候意义
沉积有机碳 碳同位素 层序分布
2010/9/14
本文通过对浙江长兴煤山Ｄ剖面长兴阶５６个样品的沉积有机碳碳同位素（δ＾１３Ｃｏｒｇ）分析，讨论了和只有机碳δ＾１３Ｃｏｒｇ在地层层序分布上的特征，及其与海水进退和碳酸盐岩δ＾１３Ｃｃａｒｂ及δ＾１８Ｏｃａｒｂ之间的关系。浙江煤山Ｄ剖面长兴阶δ＾１３Ｃｏｒｇ在地层层序上的分布总体呈现自下而上由重变轻的趋势，同时，δ＾１３Ｃｏｒｇ层序分布与生物演化及δ＾１３Ｃｃａｒｂ和δ＾１８Ｏｃａｒｂ层序分布之间具
Mechanism of CO32- substitution in carbonate-fluorapatite: Evidence from FTIR spectroscopy, 13C NMR, and quantum mechanical calculations---Reply to Nathan
Mechanism CO32- substitution carbonate-fluorapatite Evidence FTIR spectroscopy 13C NMR quantum mechanical calculations---Reply Nathan
2012/4/5
In the critical comment byNathan (1996), the author essentially claims that the samples used in our study (Regnier et al. 1994) werenot very appropriate to dem-onstrate the absence of C03P-. Furthermo...
Mechanism of CO32- substitution in carbonate-fluorapatite: Evidence from FTIR spectroscopy, 13C NMR, and quantum mechanical calculations---Discussion
Mechanism CO32- substitution carbonate-fluorapatite Evidence FTIR spectroscopy 13C NMR quantum mechanical calculations---Discussion
2012/4/5
The carbonate substitution in apatite continues to pro-voke controversies. In a recent paper, Regnier etal. (1994) challenged the existence of the hypothetical C03P- ion in carbonate-fluorapatite (fra...
13C CPMAS Nuclear Magnetic Resonance Study of the Adsorption of 2-Phenethylamine on Clays
Amine reactions with clays Clay acidic sites Solid state NMR
2011/12/1
Abstract: 2-Phenethylamine 13C-enriched in the beta position was adsorbed on four different aluminum-exchanged days: hectorite, Barasym, Laponite RD, and lithium taeniolite. The sites for adsorption w...
Chemisorption of Benzene on Cu-Montmorillonite as Characterized by FTIR and 13C MAS NMR
Benzene chemisorption 13C MAS NMR Cu-montmorillonite FTIR Poly-p-phenylene
2011/12/1
Abstract: Sorption of benzene onto Cu-montmorillonite was characterized by Fourier transform infrared (FTIR) spectroscopy and 13C magic angle spinning nuclear magnetic resonance (MAS NMR). Under anhyd...
Interpretation of Solid State 13C and 29Si Nuclear Magnetic Resonance Spectra of Kaolinite Intercalates
Dimethylsulfoxide Formamide Hydrazine Intercalate Nuclear magnetic resonance Ordering Pyridine-N-oxide
2012/1/13
13C and 29Si nuclear magnetic resonance spectroscopy with magic-angle spinning bas been used to study the short-range ordering and bonding in the structures of intercalates of kaolinite with formamide...