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Quantifying the carbon source of pedogenic calcite veins in weathered limestone:implications for the terrestrial carbon cycle
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作者 Lin Zou Lin Dong +5 位作者 Meng Ning Kangjun Huang Yongbo Peng Shujian Qin Honglin Yuan Bing Shen 《中国地球化学学报:英文版》 EI CAS CSCD 2019年第4期481-496,共16页
The continent is the second largest carbon sink on Earth’s surface.With the diversification of vascular land plants in the late Paleozoic,terrestrial organic carbon burial is represented by massive coal formation,whi... The continent is the second largest carbon sink on Earth’s surface.With the diversification of vascular land plants in the late Paleozoic,terrestrial organic carbon burial is represented by massive coal formation,while the development of soil profiles would account for both organic and inorganic carbon burial.As compared with soil organic carbon,inorganic carbon burial,collectively known as the soil carbonate,would have a greater impact on the long-term carbon cycle.Soil carbonate would have multiple carbon sources,including dissolution of host calcareous rocks,dissolved inorganic carbon from freshwater,and oxidation of organic matter,but the host calcareous rock dissolution would not cause atmospheric CO2drawdown.Thus,to evaluate the potential effect of soil carbonate formation on the atmospheric p CO2level,different carbon sources of soil carbonate should be quantitatively differentiated.In this study,we analyzed the carbon and magnesium isotopes of pedogenic calcite veins developed in a heavily weathered outcrop,consisting of limestone of the early Paleogene Guanzhuang Group in North China.Based on the C and Mg isotope data,we developed a numerical model to quantify the carbon source of calcite veins.The modeling results indicate that4–37 wt%of carbon in these calcite veins was derived from atmospheric CO2.The low contribution from atmospheric CO2might be attributed to the host limestone that might have diluted the atmospheric CO2sink.Nevertheless,taking this value into consideration,it is estimated that soil carbonate formation would lower 1 ppm atmospheric CO2within 2000 years,i.e.,soil carbonate alone would sequester all atmospheric CO2within 1 million years.Finally,our study suggests the C–Mg isotope system might be a better tool in quantifying the carbon source of soil carbonate. 展开更多
关键词 Mg isotope CALCITE VEINS Pedogenic CARBONATE SILICATE WEATHERING CARBONATE WEATHERING
伊拉克BU油田碳酸盐岩储层沉积过程数值模拟 预览
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作者 王鹏飞 霍春亮 +2 位作者 叶小明 刘卫林 徐静 《油气地质与采收率》 CAS CSCD 北大核心 2019年第4期56-61,共6页
综合利用岩心、地震、测井及分析化验等资料,分析BU油田碳酸盐岩沉积环境的控制因素,开展储层沉积过程数值模拟研究,定量表征不同沉积时期储层展布范围及沉积演化规律。研究结果表明,碳酸盐岩储层沉积过程数值模拟的可容空间变化、碳酸... 综合利用岩心、地震、测井及分析化验等资料,分析BU油田碳酸盐岩沉积环境的控制因素,开展储层沉积过程数值模拟研究,定量表征不同沉积时期储层展布范围及沉积演化规律。研究结果表明,碳酸盐岩储层沉积过程数值模拟的可容空间变化、碳酸盐岩产率等环境参数对储层分布范围的影响较大。BU油田Mishirif组MB2^1段纵向上分为Ⅰ—Ⅵ共6个小层,高能沉积带与低能沉积带交替出现,其中高能沉积带岩性主要为颗粒灰岩,在顶部Ⅰ小层较发育,而低能沉积带岩性主要为泥晶灰岩,并有高角度微裂缝发育,在Ⅵ小层底部发育。该研究成果为BU油田底注顶采的注水开发方案提供地质依据,已完成4口井方案实施,恢复了地层压力,缓解了局部压力亏空现象,整体日产油能力提高近19%,达0.94×10^4m^3/d。 展开更多
关键词 碳酸盐岩 沉积过程数值模拟 可容空间 碳酸盐岩产率 BU油田 米桑油田群
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Synthesis of Poly(isosorbide carbonate) via Melt Polycondensation Catalyzed by a KF/MgO Catalyst
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作者 SHEN Xiaolong LIU Shaoying +2 位作者 WANG Qingyin ZHANG Hua WANG Gongying 《高等学校化学研究:英文版》 SCIE CAS CSCD 2019年第4期721-728,共8页
MgO loaded with KF was prepared by using tlie impregnation method and was employed as the catalyst for tlie direct traiisesterification of diphenyl carbonate(DPC) witli isosorbide to synthesize high-molecular-weight p... MgO loaded with KF was prepared by using tlie impregnation method and was employed as the catalyst for tlie direct traiisesterification of diphenyl carbonate(DPC) witli isosorbide to synthesize high-molecular-weight poly(isosorbide carbonate)(PIC). The relationship between physical-chemical properties and catalytic performance for KF/MgO in this melt process was investigated by various characterization techniques. The basic site amount and strength were found to be responsible for this transesterification process, and the medium and strong basic sites tended to promote the polycondensation reaction. 20-KF/Mg0-500 exhibited the best catalytic performance, giving PIC with Mw of 84200 and glass transition temperature(rg) of 173℃ under optimal conditions. Additionally, 20-KF/MgO-500 was found to catalyze the transerification of DPC with isosorbide and other diols to syntliesize the corresponding poly(aliphatic diol-co-isosorbide carbonate)s(PAICs). This excellent activity can be ascribed to the presence of an abundance of basic sites and their specific basic strength on the surface of KF/MgO. 展开更多
关键词 KF/MgO Poly(isosorbide carbonate) DIPHENYL CARBONATE Transesterification Solid base
Synthesis and Properties of Poly(butylene carbonate-co-spirocyclic carbonate)
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作者 ZHU Changliang LIU Shaoying +1 位作者 WANG Qingyin ZHANG Hua 《高等学校化学研究:英文版》 SCIE CAS CSCD 2019年第4期729-734,共6页
Poly(butylene carbonateXPBC) has significantly promising applications as a degradable material in the field of polymers, while its poor thermal performance and low crystallization rate are its main defects. To overcom... Poly(butylene carbonateXPBC) has significantly promising applications as a degradable material in the field of polymers, while its poor thermal performance and low crystallization rate are its main defects. To overcome these shortcomings, a series of poly(butylene carbonate-co-spirocyclic carbonateXPBSC) copolymers were synthesized from diphenyl carbonate, 1,4-butanediol and spiroglycol via two-step polycondensation reactions, using magnesium oxide as a catalyst. Differential scanning calorimetry(DSC) results indicated that the glass transition temperature(Tg) values of PBSC copolymers were enhanced from -19℃ to 56℃ with rising the spiroacetal moiety content. Thermogravimetric analysis(TGA) results showed that the resulting PBSCs have a higher thermal stability than that of poly(butylene carbonate). Wide angle X-ray diflraction(WXRD) patterns were characterized to investigate the crystallization behaviour of PBSCs. Tensile testing demonstrated that copolymerization of spiroacetal moieties into PBC chains imparted PBSC with favourable mechanical performance. Typically, PBSC 30 had a tensile modulus of (1735±430) MPa, a tensile strength of (42±5) MPa and an elongation of 504%±36%. 展开更多
关键词 Poly(butylene carbonate) Spiroglycol DIPHENYL CARBONATE THERMAL PROPERTY
Genesis of lacustrine carbonate breccia and its significance for hydrocarbon exploration in Yingxi region, Qaidam Basin, NW China 预览
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作者 WANG Yanqing LIU Zhanguo +5 位作者 SONG Guangyong ZHANG Yongshu ZHU Chao LI Senming WANG Peng TANG Pengcheng 《石油勘探与开发:英文版》 2019年第1期104-112,共9页
To examine the reservoir type and distribution regularity of high-and stable-yield lacustrine carbonates in the upper Member of Paleogene Xiaganchaigou Formation of Yingxi region and to determine the high-efficiency h... To examine the reservoir type and distribution regularity of high-and stable-yield lacustrine carbonates in the upper Member of Paleogene Xiaganchaigou Formation of Yingxi region and to determine the high-efficiency hydrocarbon exploration direction, the origin and significance of carbonate breccia in this area were investigated based on comprehensive analysis of a large number of well cores, thin sections, rock and mineral testing and log-seismic data. The study reveals that the carbonate breccia has three origins:(1) Sedimentary breccia, formed by the event-related collapse, fragmentation and re-deposition of the early weakly consolidated carbonate rock in the steep slope of underwater paleohighs due to short-term high-energy water body reformation and other geological processes.(2) Diagenetic breccia, with breccia-like structure, formed by deformation or breaking of host rock due to growth of idiomorphic and coarse crystalline gypsum-salt minerals in the weakly consolidated argillaceous carbonate rock of the penecontemporaneous period.(3) Tectonic breccia, can be further divided into fault breccia and interlayer slip breccia according to their occurrence characteristics, both of which are closely related to activity of the Shizigou thrust Fault. With a large number of partially filled pores, vugs and fractures between breccia, the two types of tectonic breccia are high-and stable-yield reservoirs in deep Yingxi region, and may occur extensively under gypsum-salt detachment layers of adjacent areas, so they are the exploration targets in the next step. Sedimentary breccia and diagenetic breccia are of great significance in searching for large-scale carbonate reservoirs. 展开更多
关键词 Qaidam Basin Yingxi REGION LACUSTRINE CARBONATE CARBONATE BRECCIA reservoir origin PALEOGENE
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助剂Cr对Cu/SiO2催化碳酸酯加氢制甲醇性能的影响
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作者 李华博 崔园园 +1 位作者 刘逸心 戴维林 《化学学报》 SCIE CAS CSCD 北大核心 2019年第4期371-378,共8页
碳酸酯催化加氢制甲醇作为二氧化碳定向转化的间接路径具有重要意义.采用蒸氨法合成了一系列助剂铬修饰的Crx-Cu/SiO2 催化剂,系统考察了其对碳酸二乙酯催化加氢性能的影响.研究表明, 3 wt%铬修饰量的催化剂活性最优.在反应温度503 K、... 碳酸酯催化加氢制甲醇作为二氧化碳定向转化的间接路径具有重要意义.采用蒸氨法合成了一系列助剂铬修饰的Crx-Cu/SiO2 催化剂,系统考察了其对碳酸二乙酯催化加氢性能的影响.研究表明, 3 wt%铬修饰量的催化剂活性最优.在反应温度503 K、氢气压力2.5 MPa 及液时空速1.0 h^-1 条件下,碳酸二乙酯的转化率可达99%,目标产物甲醇的收率和时空得率分别为86.2%和5.6 mmolMeOH·gcat^-1·h^-1.采用X 射线粉末衍射(XRD)、N2吸脱附、透射电镜(TEM)、氢气程序升温还原(H2-TPR)、X 射线光电子能谱(XPS)和原位漫反射傅里叶变换红外光谱(In-situ DRIFTS)等手段表征了铬的修饰对催化剂物化性质的影响.结果表明,相较于未修饰的Cu/SiO2催化剂,少量铬修饰所得Crx-Cu/SiO2催化剂表面活性铜物种的分散度显著提高,且由部分铜和铬相互作用形成的亚铬酸铜物相优化了不同价态铜物种的表面分布状况及催化剂对底物的吸附构型,有效提升了其对碳酸二乙酯催化加氢制甲醇的反应性能和稳定性. 展开更多
关键词 Crx-Cu/SiO2 碳酸酯 加氢 分散性 促进效应
Sedimentological sequence and depositional evolutionary model of Lower Triassic carbonate rocks in the South Yellow Sea Basin 预览
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作者 Yu-xi Zhang Jian-wen Chen +1 位作者 Jiang-yu Zhou Yong Yuan 《中国地质(英文)》 2019年第3期301-314,共14页
Based on well logging and seismic data, combined with a comparative analysis of drilling data in the Lower Yangtze region, the sequence stratigraphic framework of the Qinglong Formation was established and divided int... Based on well logging and seismic data, combined with a comparative analysis of drilling data in the Lower Yangtze region, the sequence stratigraphic framework of the Qinglong Formation was established and divided into four third-order sequences. Each sequence is mainly composed of the transgress system tract (TST) and the high-stand system tract (HST). According to the lithology, logging curve and seismic reflection structure, the sedimentary filling characteristics and evolution law for the sequence are analyzed. The results show that each sequence is dominated by a half-cycle decline of sea level, and the rise-fall of sea level controls the distribution and evolution of sedimentary systems within the sequence. During the relative sea-level rise, sedimentation rates slow down and muddy sediments are developed. The characteristics of condensing intervals on the flooding surface are very obvious, and continental shelf and open platform deposition are mainly developed. During the relative decline of sea level, the thickness of sediments increased. The main developments were restricted platform and platform shoal environment, and locally developed evaporation platform environment. 展开更多
关键词 Lower TRIASSIC Sequence STRATIGRAPHY SEA-LEVEL change Carbonate rocks Marine GEOLOGICAL survey engineering Yellow Sea China
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可用于锂硫电池的含氟有机溶剂及其合成研究 预览
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作者 张勇耀 项文勤 +3 位作者 陈明炎 赵卫娟 倪航 高鹏飞 《有机氟工业》 CAS 2019年第2期34-41,共8页
选取了一些可应用于锂硫电池电解液并具有较为优异性能的含氟有机溶剂,并对它们的合成研究进行了综述。
关键词 锂硫电池 含氟溶剂 碳酸酯
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碳酸盐(岩)的稀土元素特征及其古环境指示意义 预览
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作者 赵彦彦 李三忠 +3 位作者 李达 郭玲莉 戴黎明 陶建丽 《大地构造与成矿学》 EI CAS CSCD 北大核心 2019年第1期141-167,共27页
稀土元素主要通过交代碳酸盐矿物的Ca^2+进入碳酸盐格架,所以沉积碳酸盐(岩)的稀土元素特征能够很好的指示沉积流体来源和古环境。常用的稀土元素指标包括稀土元素总量(ΣREE)、稀土元素配分型式、以及La、Ce、Eu、Gd和Y等元素的异常指... 稀土元素主要通过交代碳酸盐矿物的Ca^2+进入碳酸盐格架,所以沉积碳酸盐(岩)的稀土元素特征能够很好的指示沉积流体来源和古环境。常用的稀土元素指标包括稀土元素总量(ΣREE)、稀土元素配分型式、以及La、Ce、Eu、Gd和Y等元素的异常指数。碳酸盐(岩)的稀土元素含量可能受到硅酸盐矿物、Fe-Mn氧化物/氢氧化物和磷酸盐等非碳酸盐组分以及成岩蚀变作用的影响。因此,在分析过程中,我们只有排除这些影响因素,才能用碳酸盐(岩)的稀土元素指标来探讨流体来源和古环境。这要求我们采集新鲜剖面上的样品,并用适当浓度的弱酸进行分步溶样,提取适当的组分,避免样品中的非碳酸盐组分干扰原始沉积组分的稀土元素特征。不同的沉积水体和沉积相下形成的碳酸盐(岩)具有不同的稀土元素特征:从太古宙到全新世的海相碳酸盐(岩)记录了LREE亏损、La正异常和高Y/Ho值的稀土元素特征;海底孔隙水的稀土元素特征则受氧化-还原条件、离子络合形式、孔隙流体来源的制约;热液流体具有LREE富集、Eu正异常的稀土元素特征;河水和湖泊有相对平坦的稀土元素特征。因此,碳酸盐(岩)的稀土元素特征具有重要的古环境指示意义。 展开更多
关键词 碳酸盐岩 稀土元素 古环境 元素异常 流体
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Influence of the biological carbon pump effect on the sources and deposition of organic matter in Fuxian Lake,a deep oligotrophic lake in southwest China
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作者 Haibo He Zaihua Liu +5 位作者 Chongying Chen Yu Wei Qian Bao Hailong Sun Yundi Hu Hao Yan 《中国地球化学学报:英文版》 CSCD 2019年第5期613-626,共14页
Biological carbon pumping(BCP)is a key process in which dissolved inorganic carbon in terrestrial aquatic ecosystems is utilized by aquatic autotrophs for photosynthesis and transformed into autochthonous organic matt... Biological carbon pumping(BCP)is a key process in which dissolved inorganic carbon in terrestrial aquatic ecosystems is utilized by aquatic autotrophs for photosynthesis and transformed into autochthonous organic matter(AOC).However,the mechanisms underlying BCP and the amount of generated AOC deposited effectively,are still poorly understood.Therefore,we conducted a systematic study combining modern hydrochemical monitoring and a sediment trap experiment in Fuxian Lake(Yunnan,SW China),the second-deepest plateau,oligotrophic freshwater lake in China.Temperature,pH,EC(electrical conductivity),DO(dissolved O2),[HCO3^-],[Ca^2+],SIc,partial CO2(pCO2)pressure,and carbon isotopic compositions of HCO3^-(δ^13CDIc)in water from Fuxian Lake all displayed distinct seasonal and vertical variations.This was especially apparent in an inverse correlation between pCO2 and DO,indicating that variations of hydrochemistry in the lake water were mainly controlled by the metabolism of the aquatic phototrophs.Furthermore,the lowest C/N ratios and highestδ^13Corg were recorded in the trap sediments.Analyses of the C/N ratio demonstrated that the proportions of AOC ranged from 30%to 100%of all OC,indicating that AOC was an important contributor to sedimentary organic matter(OC).It was calculated that the AOC flux in Fuxian Lake was 20.43 t C km^-2 in 2017.Therefore,AOC produced by carbonate weathering and aquatic photosynthesis could potentially be a significant carbon sink and may have an important contribution to solving the lack of carbon sinks in the global carbon cycle. 展开更多
关键词 Carbonate weathering Hydrochemical variation BIOLOGICAL CARBON PUMP EFFECT Sediment trap AUTOCHTHONOUS organic CARBON CARBON sink
Geochemistry and sediment in the main stream of the Ca River basin,Vietnam:weathering process,solute-discharge relationships,and reservoir impact
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作者 Ho Thi Phuong Kenji Okubo Md.Azhar Uddin 《中国地球化学学报:英文版》 CSCD 2019年第5期627-641,共15页
In this study,we investigated the chemical composition of dissolved solids in the Ca River basin,North-Central Vietnam.Water samples were collected from August 2017 to July 2018 at three hydrological stations located ... In this study,we investigated the chemical composition of dissolved solids in the Ca River basin,North-Central Vietnam.Water samples were collected from August 2017 to July 2018 at three hydrological stations located in the main stream of the Ca River.Carbonate weathering was found as the dominant process controlling the water chemistry in that area.The average concentrations of dissolved solids generally decreased from upstream to downstream,resulting in low concentrations of the major ions in the downstream basin.Variations in the concentrations of major chemical ions and suspended solids at discharge were also investigated.Major chemical weathering products were found to behave chemostatically with increasing discharges upstream.However,dilution behaviors of solutes were shown in both midstream and downstream.Primary evidence shows that water storage in reservoirs impacts a variety of suspended solids and dissolved solids in the Ca River. 展开更多
关键词 CA River Dissolved SOLIDS GEOCHEMISTRY Carbonate WEATHERING Suspended SOLIDS
Carbonate pore type characterization using a statistical inversion method 预览
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作者 LI Bonan 《世界地质:英文版》 2019年第1期21-28,共8页
For carbonate reservoirs, vertical pore type heterogeneity records regional depositional history. However, from the geophysics point of view, these microscopic characteristics cannot be described with conventional dat... For carbonate reservoirs, vertical pore type heterogeneity records regional depositional history. However, from the geophysics point of view, these microscopic characteristics cannot be described with conventional data-driven approaches. The author presents an upscale rock physics model which includes both modeling and inverting schemes in this study. According to the statistical comparability between lab measurements and well logs, the main idea is to study and utilize inherent statistical features in naturally occurred carbonate rocks. Firstly, using the critical porosity model as rock physical theory, relationships are built between pore structures and elastic responses. Furthermore, in logging data scale, key parameters are estimated through a statistical method, and thus pore types are classified. The methodology is successfully applied in the well YS1. It is believed that this method will be a promising tool on handing pore complexity and inversion uncertainty in carbonate reservoir exploration. 展开更多
关键词 CARBONATE RESERVOIRS rock PHYSICS modeling critical POROSITY BAYESIAN estimation
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重庆綦江藻渡中二叠统沉积微相 预览
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作者 胡凯迪 陈洪德 +2 位作者 徐胜林 董翼昕 冯轲 《成都理工大学学报:自然科学版》 CAS CSCD 北大核心 2019年第3期334-341,共8页
探讨重庆綦江藻渡地区中二叠统沉积微相组合的特征及沉积环境演化。以野外地质剖面和室内薄片鉴定为基础,对藻渡地区中二叠统碳酸盐岩开展系统的岩石颗粒组分、岩石类型和沉积环境分析,并绘制相关图件。根据Dumham的碳酸盐岩沉积结构分... 探讨重庆綦江藻渡地区中二叠统沉积微相组合的特征及沉积环境演化。以野外地质剖面和室内薄片鉴定为基础,对藻渡地区中二叠统碳酸盐岩开展系统的岩石颗粒组分、岩石类型和沉积环境分析,并绘制相关图件。根据Dumham的碳酸盐岩沉积结构分类方案,主要有7种类型:生物碎屑颗粒灰岩、生物碎屑泥粒灰岩、泥灰岩、含生物碎屑泥粒灰岩、有孔虫泥粒灰岩、中-细晶白云岩和生物碎屑粒泥灰岩。研究区在中二叠世一直处于碳酸盐台地环境,发育了陆棚、台地边缘和开阔台地相,在栖霞组早期处于持续海侵过程,而栖霞组晚期经历了海退,到茅口组早期快速上升到最高点,茅口组中期开始下降,在茅口组晚期海平面大幅度快速下降到最低点。 展开更多
关键词 微相 沉积环境 碳酸盐岩 中二叠统 藻渡
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基于Hausdroff分形维数的碳酸盐岩酸蚀蚓孔计算模型 预览
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作者 齐丹 邹洪岚 +1 位作者 丁云宏 张合文 《科学技术与工程》 北大核心 2019年第6期105-109,共5页
在碳酸盐岩基质酸化过程中,一个主要特征是形成蚓孔。欧几里得空间认为蚓孔是无序的、杂乱无章的,采用经典数学的方法模拟难度极大。为了能够对酸蚓孔进行精确的定量分析、优化酸液用量及施工排量,以期获得最优酸化效果,需要建立蚓孔计... 在碳酸盐岩基质酸化过程中,一个主要特征是形成蚓孔。欧几里得空间认为蚓孔是无序的、杂乱无章的,采用经典数学的方法模拟难度极大。为了能够对酸蚓孔进行精确的定量分析、优化酸液用量及施工排量,以期获得最优酸化效果,需要建立蚓孔计算模型。以分形理论为基础,利用分数维描述蚓孔,引入'数盒子'计算法对蚓孔的Hausdroff分形维数进行研究,推导了碳酸盐岩基质酸蚀蚓孔有效作用距离的分形模型,用定量的方法描述不规则的酸蚀蚓孔等效长度。进行了影响参数敏感性分析及现场酸化实例计算,结果表明酸化后表皮系数与计算结果较为一致。对酸化优化设计具有较好的指导意义。 展开更多
关键词 碳酸盐岩 酸化 分形 Hausdroff维数 盒维数 蚓孔 溶蚀孔
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Leaf water potential and gas exchange of eucalypt clonal seedlings to leaf solar protectant 预览
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作者 Talita Miranda Teixeira Xavier Jose Eduardo Macedo Pezzopane +1 位作者 Ricardo Miguel Penchel Jose Ricardo Macedo Pezzopane 《林业研究:英文版》 CAS CSCD 2019年第1期57-64,共8页
This experiment was carried out in acclimatized greenhouses with seedlings of two hybrid clones of Eucalyptus urophylla×Eucalyptus grandis.A sunscreen protector consisting of 62.5%calcium carbonate was sprayed on... This experiment was carried out in acclimatized greenhouses with seedlings of two hybrid clones of Eucalyptus urophylla×Eucalyptus grandis.A sunscreen protector consisting of 62.5%calcium carbonate was sprayed on the seedlings at weekly intervals.Water stress was induced by suspending irrigation until the soil reached 30%available water and water was then replaced so that it returned to field capacity.Gas exchange and leaf water status were measured after 50 days.The experiment was set up in a 4×2 factorial randomized block design in four distinct environments:(1)temperatures less than 21.2℃and vapor pressure deficit of 0.15 kPa;(2)intermediate temperatures of 24.2℃and vapor pressure deficit of 0.69 kPa;(3)high temperatures of 27.0℃and high vapor pressure deficit of 1.4 kPa;and,(4)high temperature of 27.0℃and vapor pressure deficit below 1.10 kPa.Two leaf sun protector treatments were used,with five replications each.High atmospheric demand acted as a stress factor for the seedlings during the initial growth phase.Applications of leaf sunscreen protector provided beneficial effects in maintaining optimum water status and gas exchanges of the plants under water stress. 展开更多
关键词 EUCALYPTUS urophylla×Eucalyptus grandis Calcium CARBONATE Water stress ATMOSPHERIC DEMAND
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氮掺杂碳上单原子锌:CO2固定和转化的高效稳定催化剂 预览
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作者 Xinjiang Cui Xingchao Dai +5 位作者 Annette-Enrica Surkus Kathrin Junge Carsten Kreyenschulte Giovanni Agostini Nils Rockstroh Matthias Beller 《催化学报》 SCIE EI CAS CSCD 北大核心 2019年第11期1679-1685,共7页
环氧化合物与CO2环加成反应是环状碳酸酯合成和CO2利用的一种直接的原子经济方法,目前主要采用均相金属络合物催化此类转化反应.本文报道了一种新型多相Zn基催化剂,它可方便地通过热解活性炭负载的邻菲啰啉络合Zn(OAc)2而得到.详细的结... 环氧化合物与CO2环加成反应是环状碳酸酯合成和CO2利用的一种直接的原子经济方法,目前主要采用均相金属络合物催化此类转化反应.本文报道了一种新型多相Zn基催化剂,它可方便地通过热解活性炭负载的邻菲啰啉络合Zn(OAc)2而得到.详细的结构表征证实该材料中存在单原子Zn活性位.与Zn基纳米粒子催化剂相比,本文制备的单原子Zn催化剂在环氧化物环加成反应中表现出更高的活性和稳定性.采用该优化的催化剂成功地以高产率得到了一系列碳酸酯,该催化剂具有较好的基团容忍性. 展开更多
关键词 多相催化 单原子催化剂 二氧化碳 环加成 碳酸酯
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Thermodynamics of NaHCO3 decomposition during Na2CO3-based CO2 capture
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作者 Sam Toan William O’Dell +5 位作者 Christopher K.Russell Sun Zhao Qinghua Lai Huiping Song Ying Zhao Maohong Fan 《环境科学学报:英文版》 SCIE EI CAS CSCD 2019年第4期74-80,共7页
Amine-basedcarbon-capture technologies have been shown to be energetically expensive and to cause significant environmental and epidemiological impacts due to their volatility.Bicarbonate formation from carbon dioxide... Amine-basedcarbon-capture technologies have been shown to be energetically expensive and to cause significant environmental and epidemiological impacts due to their volatility.Bicarbonate formation from carbon dioxide’s reaction with water has been suggested as an effective alternative for capturing CO2;however,the thermodynamics of this reaction are not well understood.This study experimentally determined the equilibrium constant of sodium bicarbonate(Na HCO3)decomposition to sodium,water,and carbon dioxide;the study also compared the equilibrium constant to theoretical calculations.Using a combination of experimentation and thermodynamic relationships,the unitless equilibrium constants of the forward and reverse reactions were calculated accurately(error<±9%and<±4%,respectively).Equilibrium data were calculated using enthalpy and entropy values of each component of Na HCO3decomposition at temperatures ranging from 25 to 155°C respectively.These results offer more data essential to optimizing Na HCO3use in environmentally friendly nextgeneration CO2-capture technologies. 展开更多
关键词 SODIUM BICARBONATE SODIUM carbonate Gibbs free energy ENTHALPY Entropy
徐州地区碳酸盐岩溶蚀特征及影响因素分析 预览
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作者 武鑫 王艺霖 +2 位作者 黄敬军 潘欢迎 万军伟 《地质科技情报》 CAS CSCD 北大核心 2019年第3期120-126,共7页
徐州地区碳酸盐岩主要赋存于震旦系、寒武系和奥陶系3个地层中。为研究徐州地区碳酸盐岩的溶蚀规律,于2条碳酸盐岩地层剖面上取样44件,在常温常压、相同CO2浓度条件下开展了5,10,15,20,30 d的室内溶蚀试验。试验结果表明,矿物成分和化... 徐州地区碳酸盐岩主要赋存于震旦系、寒武系和奥陶系3个地层中。为研究徐州地区碳酸盐岩的溶蚀规律,于2条碳酸盐岩地层剖面上取样44件,在常温常压、相同CO2浓度条件下开展了5,10,15,20,30 d的室内溶蚀试验。试验结果表明,矿物成分和化学成分是影响碳酸盐岩溶蚀的主要因素,比溶蚀度和比溶解度的总体变化趋势是白云岩<灰岩<膏溶岩,随CaO质量分数的变化呈现正相关关系,随MgO质量分数的变化略呈负相关关系。当酸不溶物质量分数小于30%时,有利于促进碳酸盐岩的溶蚀作用;当酸不溶物质量分数大于30%时,对碳酸盐岩的溶蚀有抑制作用。原生结构以及节理构造也通过改变碳酸盐岩与水的接触面积而影响溶蚀能力,溶蚀作用排序为泥晶>粉晶>细晶>粗晶。当岩石中发育断裂、节理和破碎带时,溶蚀作用首先沿这些脆弱带进行。综合各影响因素分析,徐州地区马家沟组、张夏组、赵圩组、九顶山组溶蚀能力最强;炒米店组、馒头组、张渠组、望山组、魏集组、贾园组溶蚀能力中等;三山子组、倪园组、昌平组溶蚀能力相对较弱。 展开更多
关键词 碳酸盐岩 溶蚀试验 比溶蚀度 比溶解度 影响因素
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复杂碳酸盐岩成像地质解译:以柴达木盆地砂西地区为例 预览
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作者 吴颜雄 赵辉 +4 位作者 杨智 李海鹏 刘乐 刘君林 施奇 《地质科技情报》 CAS CSCD 北大核心 2019年第1期265-269,共5页
柴达木盆地为一高原咸化湖盆,渐新世早期沉积了复杂的碳酸盐岩。砂西地区下干柴沟组岩性包括砂屑灰/云岩、藻灰/云岩、泥晶灰/云岩、泥灰岩、灰质砂岩等。常规测井能较好地区分纯碳酸盐岩,但对于混积型的碳酸盐岩识别难度较大。基于岩... 柴达木盆地为一高原咸化湖盆,渐新世早期沉积了复杂的碳酸盐岩。砂西地区下干柴沟组岩性包括砂屑灰/云岩、藻灰/云岩、泥晶灰/云岩、泥灰岩、灰质砂岩等。常规测井能较好地区分纯碳酸盐岩,但对于混积型的碳酸盐岩识别难度较大。基于岩心刻度成像测井,建立了6种成像测井模式:高阻亮色块状模式、中高阻橙色块状模式、暗色块状模式、黄白相间正弦曲线模式、亮色-明暗相间正弦曲线模式、橙色-明暗相间正弦曲线模式。这6种模式对有效识别下干柴沟组地层岩性有很强的指导作用。 展开更多
关键词 柴达木盆地 砂西地区 碳酸盐岩 成像测井 地质解译
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一种碳酸盐岩气藏地层孔隙压力计算方法 预览
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作者 陶磊 赵越哲 +1 位作者 何岩峰 邓嵩 《常州大学学报:自然科学版》 CAS 2019年第3期88-92,共5页
中国大多数富集油气区发育了碳酸盐岩地层,但碳酸盐岩地层压力复杂多变,计算方法并不成熟。研究提出了一种多元回归模型以计算地层孔隙压力。碳酸盐岩地层声波速度可由岩石骨架和孔隙流体的声波速度加权合成,岩石骨架声波速度的主要影... 中国大多数富集油气区发育了碳酸盐岩地层,但碳酸盐岩地层压力复杂多变,计算方法并不成熟。研究提出了一种多元回归模型以计算地层孔隙压力。碳酸盐岩地层声波速度可由岩石骨架和孔隙流体的声波速度加权合成,岩石骨架声波速度的主要影响因素为骨架密度、垂直有效应力及泥质含量,孔隙流体声波速度的主要影响因素为流体密度、地层孔隙压力及地层温度,通过以上理论建立模型方程,用实测值与计算值回归出模型系数,并进行区域地层孔隙压力预测。以中国西部地区某碳酸盐岩气藏的实测数据为例,对数据进行回归,得出了模型方程,进行了模型结果验证,计算结果与实测值对比分析,误差达到6%以下,符合工程需求,该模型可应用于此区域的地层孔隙压力预测。 展开更多
关键词 碳酸盐岩 气藏 地层压力 多元回归 纵波速度
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