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1.
采用无机盐溶胶-凝胶法制备了颗粒均匀的形态为针状的(Eu2+,Dy3+)SrAl2O4纳米粉体.通过TG-DTA分析和X射线衍射和扫描电镜分析方法,对样品进行了微观结构和表面形态的表征.研究了纳米(Eu2+,Dy3+)SrAl2O4粉体在不同烧结温度下固相反应过程和成相规律.实验结果表明,当样品的烧结温度为500 ℃时是单一的Sr(NO3)2晶相;750 ℃左右生成了Sr3Al2O6,并伴有少量SrAl2O4晶体;1 100 ℃是生成了结晶度良好的针状纳米(Eu2+,Dy3+)SrAl2O4粉体.通过计算,样品粉体晶粒平均为80~100 nm.该晶体粒度随烧结温度升高而逐渐变大.  相似文献   

2.
基于插件技术的GIS应用框架的研究与实现   总被引:13,自引:0,他引:13  
吴亮  杨凌云  尹艳斌 《地球科学》2006,31(5):609-614
为了解决传统GIS软件的行业化、专业化和开发成本较高的问题, 使GIS软件面向大众化、低成本化发展, 构建插件式GIS应用框架平台, 能提供一个具有良好的复用性和灵活的可扩展性平台, 同时为项目实施所面对的特定知识应用领域提供很好支持软件框架具有实际意义.在深入研究“平台+插件”模型的本质与实现机制后, 提出了基于插件技术的GIS应用框架的对象模型、消息机制和层次结构.同时将这一理论成果成功应用到了大型GIS平台---MAPGIS7.0的开发与实践中, 实现了全插件式的GIS应用框架, 使平台功能扩展和GIS的应用开发具有了可行性.   相似文献   

3.
<正>为了能够快速高效地处理稿件,缩短出版周期,《煤田地质与勘探》编辑部开通了自己的网站,并安装了编辑部远程稿件处理系统。从2010年3月开始,作者投稿、专家审稿、编辑办公及读者阅览均在网站在线进行。作者投稿请登录http://mtdz.jourserv.com/网站注册后进行在线投稿(注:请记好自已的用户名和密码,便于查询稿件编辑录用情况)。  相似文献   

4.
息Yang  张明平 《广西地质》2001,14(2):47-51
网络经济已成为新的社会生产力的代表。广西地质矿产勘查开发局应该利用其行业和地域方面的固有优势,积极参与网络经济,以期打开矿业市场。文章提出了建立矿业网站的设想和框架。  相似文献   

5.
王荣宝 《地质与资源》2005,14(2):146-148
地质、矿产、交通、国土、测绘等众多行业都与空间数据密切相关.空间数据基准框架决定了空间数据的准确性、统一性和实用性.本文从国内外发展现状出发,简述了我国目前大地坐标框架存在的问题,论述了建立省域C级GPS网并精化似大地水准面的作用和意义,并提出了建立省域C级GPS网并精化似大地水准面的技术方案和相关问题.  相似文献   

6.
吕小婷  郎宝平 《地质通报》2011,30(9):1473-1478
通过将中国地调局网站与美国地调局网站,在网站的用户、结构、内容、在线技术、信息政策等方面进行对比,分析了中国地调局网站建设中存在的不足,提出了加强网站规划、优化网站结构、建设网站集群、统一网站形象等改进建议,以期对今后网站建设能有一定的帮助.  相似文献   

7.
正《西北地质》独立网站以其清新活泼、美观大方、内容丰富,方便实用为特点。目前,《西北地质》已从2001年起全文上网,很多作者都在访问《西北地质》网站并使用在线投稿。由于《西北地质》具有广泛的学术影响力,因而市场上出现了许多假冒的《西北地质》网站,使一些作者上当受骗,造成了个人损失。因此,《西北地质》特别提醒作者注意,在《西北地质》网站投稿,作者投稿一律请登陆《西北地质》网站(www.xbdz.  相似文献   

8.
董建华  师利君  吴晓磊  王璐 《岩土力学》2023,(11):3141-3150
新型框架通风锚杆是自主研发的一种冻土边坡柔性支挡结构,具有广阔的应用前景。为了探究新型框架通风锚杆的降温效果及力学效应,设计了能够加载、变角度且可同时测得温度、水分、风速及内力的多功能冻土实验箱,并搭建了新型框架通风锚杆支护多年冻土边坡的室内试验,得到了不同时期内边坡温度、水分、风速及支挡结构内力变化规律。试验结果表明:越靠近通风锚杆,土体温度和水分变化越明显,新型通风锚杆能吸收冷量并沿轴向和径向传递和扩散,具有良好的降温效果,并保持冻土边坡的冻结状态。新型通风锚杆内风速变化规律与外界风速变化较为一致,外界风速越大,新型框架通风锚杆降温效果越明显。不同时期内,新型锚杆轴力呈抛物线型变化,冻结期轴力大于融化期,且冻结期框架内力是融化期的2~3倍。研究结果可为新型框架通风锚杆的设计和工程应用提供指导。  相似文献   

9.
《沉积学报》2008,26(4)
《沉积学报》编辑部网站即日起正式开通,网址为:www.cjxb.ac.cn。本网站具编辑部办公管理,作者在线投稿、在线查询,专家远程审稿,过刊浏览等现代化办公管理模式,欢迎大家访问并提出意见和建议。作者投稿请登录www.cjxb.ac.cn注册后进行在线投稿(注:请记好自已的用户名和密码,便  相似文献   

10.
正最近发现,有些不法之徒窃取《吉林地质》杂志刊号、封面等杂志信息,以《吉林地质》杂志网站的名义收录论文。为维护我刊的良好声誉和广大读者的利益,《吉林地质》郑重声明如下:我刊在线投稿网站已经暂时关闭,在新网站投入使用前,现在网络上所有网址均是假冒网站。本刊与其他任何网站无合作关系,请广大作者注意甄别,谨防受骗上当。我刊保留对涉嫌侵权的单位或个人追究法律责任的权利。  相似文献   

11.
The reaction chlorite+dolomite=spinel+ forsterite+calcite+CO2+H2O has been studied with hydrothermal equipment technique in a C-O-H fluid at P fluid=1,000, 2,000 and 3,000 bars and fo2 controlled by NB or QFM buffer. The equilibrium conditions for the reaction has been determined as log K=–57,119/T+95.77+0.9860(P-1)/T(bar,°K). The mineral mixtures had an excess of dolomite. The composition of the chlorite among the reaction products has been analysed and found to have a higher Al/Si ratio than clinochlore.  相似文献   

12.
Hydrothermal experiments with mixtures of synthetic minerals have shown the reversibility of the reaction 5 phlogopite + 6 calcite + 24 quartz = 3 tremolite + 5 K-feldspar + 2 H2O + 6 CO2. In an isobaric T – diagram the equilibrium curve reaches a maximum at = 0,75. The P, T-values for this maximum are: 2 kb-523°; 4 kb-585°; 6 kb-625°; P±5%, T±10° C. These results give a first approximation of the P, T conditions responsible for a similar mineral reaction which has been recorded from natural metamorphic assemblages.

Herrn Prof. H. G. F. Winkler danke ich für anregende Diskussionen, desgleichen Herrn Dr. D. Puhan für wichtige Hinweise und Mitteilung seiner exp. Daten. Herrn Prof. V. Trommsdorff und Herrn P. H. Thompson bin ich für petrographische Angaben zu Dank verpflichtet. Der Aufbau der Hydrothermalanlage und die Finanzierung der laufenden Untersuchungen wurde aus den Mitteln des Fonds zur Förderung der wissenschaftlichen Forschung ermöglicht. Für diese Unterstützung gilt daher mein besonderer Dank.  相似文献   

13.
何涛 《铀矿地质》2002,18(5):318-320
本介绍了用VC++对MAPGIS进行二次开发的方法和基本函数以及软件开发实例。  相似文献   

14.
Six equilibria among quartz, plagioclase, biotite, muscovite, and garnet were empirically calibrated using mineral composition data from 43 samples having the assemblage quartz+muscovite+biotite+garnet+plagioclase+Al2SiO5 (sillimanite or kyanite). Pressures and temperatures in the data set used for calibration were determined through the simultaneous application of garnet-biotite geothermometry and garnet-quartz-plagioclase-Al2SiO5 geobarometry. Thermodynamic expressions for four of the six equilibria incorporate interaction parameters that model non-ideality in the mixing of cations in the octahedral sites of both muscovite and biotite. With pressure chosen as the dependent variable, multiple regression was used to solve for unknowns in the equilibrium thermodynamic expressions. The regressions yielded multiple correlation coefficients ranging from 0.983 to 0.999, with corresponding standard deviations of 338 and 92 bars in the residuals. The standard deviations in the residuals may be explained largely or entirely by the propagation of errors associated with electron microprobe analysis. These equilibria enable the determination of pressures from equilibrium assemblages of quartz+garnet+plagioclase+muscovite+biotite, and give results closely comparable to the experimentally calibrated garnet-quartz-plagioclase-Al2SiO5 geobarometer. Geobarometric applications should be restricted to rocks in which equilibrium constants and compositional variables fall within the same ranges as those used for calibration.  相似文献   

15.
The reaction 2 epidote+2 calcite+3 wollastonite3 grossular-andraditess+ 2 CO2+1 H2O has been explored by hydrothermal experiments at a total fluid pressure of 1000 bars. For a grossular-andraditess of andradite 25 composition, the isobaric univariant curve passes through the points 458°C: XCO2=0.00; 521°C: XCO2=0.026; 523°C: XCO2=0.052; 526°C: 0.088; 528°C: XCO2=0.104. This curve intersects the isobaric univariant curve of the reaction calcite+quartz+[H2O] wollastonite+CO2+[H2O] at the isobaric invariant point around 528°C and XCO2=0.12. At higher values of XCO2, this reaction is replaced by another one, namely: 2 epidote+5 calcite+3 quartz3 grossular-andraditess+5 CO2+ 1 H2O. It is demonstrated that both the reactions do actually take place during the metamorphism of calcareous rocks. The petrologic significance of contrasted sequence of reactions within this system observed by various workers is also discussed.  相似文献   

16.
The equilibrium curve for the reaction 3 dolomite + 1 K-feldspar + 1 H2O=1 phlogopite + 3 calcite + 3 CO2 was determined experimentally at a total gas pressure of 2000 bars using two different methods.
  1. In the first case water alone was added to the reactants. The CO2 component of the gas phase was producted solely by the reaction under favourable P-T conditions. This manner of carrying out the reaction is called the “water method”. With this method sufficient time must be allowed for the gas phase to attain a constant composition (see Fig. 1). Reverse reactions were carried out using reaction products of the forward reaction.
  2. In the second case silver oxalate + water were added to the reactants. Breakdown of the silver oxalate leads to formation of a CO2-H2O gasphase of definite composition. At constant temperature and gas pressure the \(X_{{\text{CO}}_{\text{2}} } \) determines whether the reaction products will be phlogopite + calcite or dolomite + K-feldspar. In this case it is not necessary to wait for equilibrium to be attained. This method is abbreviated the “oxalate method”. Reactants for reverse reactions are not identical with the products of the forward reaction.
At high temperatures the results of the two different methods agree well (see Tables 1 and 2). Equilibrium was attained in one case at 490° C and \(X_{{\text{CO}}_{\text{2}} } \) of approximately 0.77, and in the other case at 520° C and \(X_{{\text{CO}}_{\text{2}} } \) of 0.90. At lower temperatures there are considerable differences in the results. With the water method an \(X_{{\text{CO}}_{\text{2}} } \) of about 0.25 was reached at 450° C. With the oxalate method dolomite K-feldspar and water still react with each other at even higher \(X_{{\text{CO}}_{\text{2}} } \) values. Phlogopite, calcite and CO2 are formed together with metastable talc. There are no criteria to indicate which of the methods is the correct one at lower temperatures and in Fig. 2, therefore, both equilibrium curves are plotted.  相似文献   

17.
Under hydrous conditions the stability field of the assemblage Mg-cordierite+K feldspar+quartz is limited on its low-temperature side by the breakdown of cordierite+K feldspar into muscovite, phlogopite and quartz, whereas the high-temperature limit is given by eutectic melting. The compatibility field of the assemblage ranges from 530° C to 745° C at 1 kbar , from 635 to 725° C at 3 kbars , from 695 to 725° C at 5 kbars and terminates at 5.5 kbars . Most components not considered in the model system will tend to restrict this field even more. However, the condition < P total will increase the range of stable coexistence drastically, making the assemblage common at elevated temperatures from contact metamorphic rocks up to intermediate pressure granulites of appropriate bulk composition.  相似文献   

18.
19.
EPR investigations of yellow-green titanites from four localities showed presence of V4+ and Fe3+. They were investigated at X-band and room temperature. For V4+ the principal values of the g matrix and 51V hyperfine splitting and the directions of their principal axes indicate presence of a VO2+ ion substituting for Ti. Due to a high zero-field splitting only approximate values of the fine structure parameters of Fe3+ could be determined. With directions of their principal axes very similar to those of V4+ this ion must also substitute for Ti. Unusually large linewidths for both ions with little variation for samples from different localities are ascribed to the reported domain structure of titanites and accumulation of impurities in the domain boundaries. While for Fe3+ a small variation of the fine structure parameters explains this broadening, for V4+ a distribution of g-factors equal to its total anisotropy must be responsible whereas the V=0 bond length is remarkably constant. Due to preferential incorporation of impurities in the grain boundaries a contribution of dipolar broadening cannot be excluded.  相似文献   

20.
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