检索结果-南通市图书馆

Effect of temperature on Lu’an bituminous char structure evolution in pyrolysis and combustion

在线全文

学校读者我要写书评

暂无评论

Frontiers in Energy 2021年第1期15卷 14-25页

作者： Yandi ZHANG Yinhe LIU Xiaoli DUAN Yao ZHOU Xiaoqian LIU shijin xu State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong UniversityXi'an 710049China

In the process of pyrolysis and combustion of coal particles, coal structure evolution will be affected by the ash behavior, which will further affect the char reactivity, especially in the ash melting temperature zone. Lu’an bituminous char and ash samples were prepared at the N_(2) and air atmospheres respectively across ash melting temperature. A scanning electron microscope (SEM) was used to observe the morphology of char and ash. The specific surface area (SSA) analyzer and thermogravimetric analyzer were respectively adopted to obtain the pore structure characteristics of the coal chars and combustion parameters. Besides, an X-ray diffractometer (XRD) was applied to investigate the graphitization degree of coal chars prepared at different pyrolysis temperatures. The SEM results indicated that the number density and physical dimension of ash spheres exuded from the char particles both gradually increased with the increasing temperature, thus the coalescence of ash spheres could be observed obviously above 1100℃. Some flocculent materials appeared on the surface of the char particles at 1300℃, and it could be speculated that β-Si_(3)N_(4) was generated in the pyrolysis process under N_(2). The SSA of the chars decreased with the increasing pyrolysis temperature. Inside the char particles, the micropore area and its proportion in the SSA also declined as the pyrolysis temperature increased. Furthermore, the constantly increasing pyrolysis temperature also caused the reactivity of char decrease, which is consistent with the results obtained by XRD. The higher combustion temperature resulted in the lower porosity and more fragments of the ash.

关键词： bituminous char pyrolysis ash structure evolution reactivity

Differentiation and accumulation of fluids in A-type granites: Evidence from accessory mineral study

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2000年第17期45卷 1609-1613页

作者： WANG Rucheng ZHAO Guangtao WANG Dezi LU Jianjun xu shijin Department of Earth Sciences and State Key Laboratory for Mineral Deposits Research Nanjing UniversityNanjing 210093China Department of Ocean Geology Qingdao Ocean UniversityQingdao 266003China

The Laoshan A-type granite is a highly evolved granite body. The study on accessoryminerals indicates that there exist differentiation and accumulation of fluids during the late stage of evolution of the granite. The released fluids are rich in rare-earth elements (REE), high-field-strength elements (HFSE, such as Nb, Ta, Zr, Hf, Th, U, and Y) and volatiles (F, P, CO2, etc.). Owing to the presence of fluid, accessory mineral assemblages have changed during the evolution of A-type granite, and are especially characterized by large amounts of independent REE-Nb-Y-Th minerals present in the late facies. Late-accumulation of fluids may be of the general feature of A-type granites, at least of highly evolved ones.

关键词： accessory minerals fluid A-type granite Laoshan.

Sm-Nd dating and Nd-Sr isotopic characteristics of the Shimian ophiolite suiten,Sichuan Province

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2002年第22期47卷 1897-1901页

作者： SHEN Weizhou xu shijin GAO Jianfeng YANG Zhusheng YANG Qiwen Department of Earth Sciences and State Key Laboratory of Mineral Deposit Research Nanjing UniversityNanjing 210093China Geological Survey Institute Panxi Geological TeamSichuan Bureau of Geology and Mineral Exploration and DevelopmentXichang 615000China

By mcasuring the Sm-Nd and Rb-Sr isotopiccompositions of harzburgite and gabbro from Shimianophiolite suite, we got the whole rock Sm-Nd isochron age of(938 ± 30) Ma (2σ), and the e Nd of 7.6 ± 0.8 (2σ), which showsthat the ophiolite was formed at the Early *** obvious change (0.70209-0.70708) of Isr values of theophiolite is caused by the meteoric hydrothermal *** high εNd values indicate that the primitive magma wasderived from the intense depleted mantle rescrvoir. It is sug-gested that this area was in a back-arc basin environmentduring the Early Neoproterozic.

关键词： Sm-Nd dating Nd-Sr isotopes ophiolite suite back-arc basin Shimian County Sichuan Province.

U-Pb dating of zircon grains from the ore-bearing plagioclase amphibolite in the Dashuigou Te deposit

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1998年第17期43卷 1486-1489页

作者： shijin xu Weizhou Shen Rucheng Wang Jianjun Lu Xiaoming Chen Yuping Lin Nanjing Univ Dept Earth Sci Nanjing 210093 Peoples R China

The Dashuigou Te deposit is a unique independent one found in the world, and hosted in the plagioclase amphibolite. The upper intercept age of single zircon from the amphibolite can be considered to be the crystallization age of the source-rock of the amphibolite (tholeiitic basalt), while the lower intercept is nearly consistent with the time of the tectono-thermal event.

关键词： U-Pb dating single zircon grain plagioclase amphibolite Dashuigou Te deposit.

Material Properties of Marine Hydrogenous Ferromanganese Crust and Its Performance in Desulfurization

在线全文

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 2006年第3期80卷 441-450页

作者： LU Xiancai HOU Qingfeng LIU Xiandong YANG Kan WANG Rucheng LING Hongfei xu shijin State Key Laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing Jiangsu 210093

Marine hydrogenous ferromanganese crust, an important metal resource in the future, has significant potential in various applications as a type of natural nano-structured material. By employing scanning electronic microscopy, nitrogen adsorption-desorption isotherm measurement, Xray fluorescence spectrometer and X-ray diffraction methods, the micro-structure, surface properties and chemical composition of several plate-like ferromanganese crusts sampled from the northwestern Pacific were investigated comprehensively. Although obvious differences were observed from different layers, the crust is a typical porous material with high specific surface area, unique pore structure and abundant transition elements. Furthermore, the performance of natural crust in desulfurization process was preliminarily tested in laboratory experiments. The suffur capacities of the crust are 13.1% and 18.1% at room temperature and 350 ℃, respectively. The crust can be used not only as a metal resource, but also as an environmental material.

关键词： ferromanganese crust pore structure surface property desulfurization

Classification and Source Materials of Continental Crust Transformation Series Granitoids in South China

在线全文

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 1990年第3期64卷 287-298页

作者： Liu Changshi Zhu Jinchu Shen Weizhou xu shijin Department of Earth Sciences, Nanjing University, Nanjing, Jiangsu Jiang Minxi Department of Earth Sciences Nanjing University Nanjing Jiangsu

The granitoids of the continental crust transformation series in South China may be divided into threetypes: (1) synorogenic migmatic and magmatic type. (2) anorogenic continental crust anatexis type, and (3)syncollision type. Based on the results of Sr and Nd isotopic determinations, the source material compositionof the three types of granitoids is calculated with crust-mantle binary mixing simulation. The calculations indi-cate that the granitoids of the first type consist of 78.6-89.7% upper crust endmember materials and15.0-10.3% depleted mantle endmember materials, the granitoids of the second type are composed of 63.7%upper crust endmember materials and 36.3% depleted mantle endmember materials, and those of the third type100% upper crust endmember materials. Hence. the source material composition of the granitoids of all thethree types is dominated by upper crust endmembers.

关键词： Classification and Source Materials of Continental Crust Transformation Series Granitoids in South China Source

在线全文

学校读者我要写书评

暂无评论

有杆抽油系统故障诊断的人工神经网络方法

石油学报 2006年第2期27卷 107-110页

作者：徐芃徐士进尹宏伟南京大学地球科学系江苏南京210093

将人工神经网络用于有杆抽油系统故障的自动识别。对江苏油田的实测示功图数据进行了预处理,利用Matlab6.5进行编程,应用相同的数据对BP神经网络模型和自组织竞争神经网络模型的识别效率进行了对比。结果表明,由自组织竞争神经网络建立... 详细信息

将人工神经网络用于有杆抽油系统故障的自动识别。对江苏油田的实测示功图数据进行了预处理,利用Matlab6.5进行编程,应用相同的数据对BP神经网络模型和自组织竞争神经网络模型的识别效率进行了对比。结果表明,由自组织竞争神经网络建立的模型对测试数据的正确识别率更高,识别效果稳定。因此,将自组织竞争神经网络应用于示功图的自动识别问题对实现有杆抽油系统故障诊断的自动化以及实现真正意义上的数字油田提供了一种有效途径。

关键词：有杆抽油系统故障诊断示功图自动识别 BP神经网络自组织竞争神经网络诊断模型

STUDY ON THE18O DEPLETION IN THE SUZHOU Nb,Ta-BEARING GRANITE

在线全文

学校读者我要写书评

暂无评论

南京大学学报(自然科学) 1997年第2期 152-154页

作者： Wang Rucheng xu shijin Shen Weizhou xu Keqin (Department of Earth Sciences,Nanjing University,210093,Nanjing,PRC) Keywords Oxygen isotope, 18 O depletion, fluid rock interaction, the Suzhou granite

ＳＴＵＤＹＯＮＴＨＥ１８ＯＤＥＰＬＥＴＩＯＮＩＮＴＨＥＳＵＺＨＯＵＮｂ，Ｔａ┐ＢＥＡＲＩＮＧＧＲＡＮＩＴＥＷａｎｇＲｕｃｈｅｎｇＸｕＳｈｉｊｉｎＳｈｅｎＷｅｉｚｈｏｕＸｕＫｅｑｉｎ（ＤｅｐａｒｔｍｅｎｔｏｆＥａｒｔ... 详细信息

ＳＴＵＤＹＯＮＴＨＥ１８ＯＤＥＰＬＥＴＩＯＮＩＮＴＨＥＳＵＺＨＯＵＮｂ，Ｔａ┐ＢＥＡＲＩＮＧＧＲＡＮＩＴＥＷａｎｇＲｕｃｈｅｎｇＸｕＳｈｉｊｉｎＳｈｅｎＷｅｉｚｈｏｕＸｕＫｅｑｉｎ（ＤｅｐａｒｔｍｅｎｔｏｆＥａｒｔｈＳｃｉｅｎｃｅｓ，Ｎａｎｊｉｎｇ...

关键词： Ta Nb,Ta-BEARING SUZHOU ON STUDY THE DEPLETION GRANITE

Yttrium zoning in garnet from the Xihuashan granitic complex and its petrological implications

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2003年第15期48卷 1611-1615页

作者： WANG Rucheng, HU Huan, ZHANG Aicheng, xu shijin & WANG Dezi State Key Laboratory for Mineral Deposits Research, Department of Earth Sciences, Nanjing University, Nanjing 210093, China Correspondance should be addressed to Wang Rucheng (e-mail: rcwang@***) State Key Laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing 210093 China

The Xihuashan granitic complex is characterized by enrichment in rare-earth elements (REE). In particular, the second-stage granite (G-b) is markedly enriched in yttrium, and therefore contains complex associations of Y-bearing minerals. In this granite, garnet displays specific yttrium zoning with an Y-rich core and a 揷lean?rim. Besides minute inclusions of Y-bearing minerals, garnet involves a striking amount of Y and HREE in its central area. It is suggested that enrichment in Y in the garnet core accords with that in the melt as a result of REE magmatic fractionation. However, the 揷lean?rim may be the direct result of accumulation of fluid phases in the magma, which is virtually unfavorable for the entrance of REE in the garnet structure.

关键词：钇石榴石花岗岩岩石学岩浆水热作用