scholarly journals Compositional Variation of Eudialyte-Group Minerals from the Lovozero and Ilímaussaq Complexes and on the Origin of Peralkaline Systems

Minerals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 548
Author(s):  
Lia N. Kogarko ◽  
Troels F. D. Nielsen
Keyword(s):  
Linear Trend ◽  
Major And Trace Elements ◽  
High Tech ◽  
Compositional Variation ◽  
Elemental Distribution ◽  
Magma Chambers ◽  
Eudialyte Group ◽  
System A ◽  
Distribution Of Elements ◽  
World Class

The Lovozero complex, Kola peninsula, Russia and the Ilímaussaq complex in Southwest Greenland are the largest known layered peralkaline intrusive complexes. Both host world-class deposits rich in REE and other high-tech elements. Both complexes expose spectacular layering with horizons rich in eudialyte group minerals (EGM). We present a detailed study of the composition and cryptic variations in cumulus EGM from Lovozero and a comparison with EGM from Ilímaussaq to further our understanding of peralkaline magma chambers processes. The geochemical signatures of Lovozero and Ilímaussaq EGM are distinct. In Lovozero EGMs are clearly enriched in Na + K, Mn, Ti, Sr and poorer Fe compared to EGM from Ilímaussaq, whereas the contents of ΣREE + Y and Cl are comparable. Ilímaussaq EGMs are depleted in Sr and Eu, which points to plagioclase fractionation and an olivine basaltic parent. The absence of negative Sr and Eu anomalies suggest a melanephelinitic parent for Lovozero. In Lovozero the cumulus EGMs shows decrease in Fe/Mn, Ti, Nb, Sr, Ba and all HREE up the magmatic layering, while REE + Y and Cl contents increase. In Lovozero EGM spectra show only a weak enrichment in LREE relative to HREE. The data demonstrates a systematic stratigraphic variation in major and trace elements compositions of liquidus EGM in the Eudialyte Complex, the latest and uppermost part of Lovozero. The distribution of elements follows a broadly linear trend. Despite intersample variations, the absence of abrupt changes in the trends suggests continuous crystallization and accumulation in the magma chamber. The crystallization was controlled by elemental distribution between EGM and coexisting melt during gravitational accumulation of crystals and/or mushes in a closed system. A different pattern is noted in the Ilimaussaq Complex. The elemental trends have variable steepness up the magmatic succession especially in the uppermost zones of the Complex. The differences between the two complexes are suggested to be related dynamics of the crystallization and accumulation processes in the magma chambers, such as arrival of new liquidus phases and redistributions by mush melts.

X-ray mapping without STEM

1994 ◽  
Vol 52 ◽  
pp. 508-509
Author(s):  
Judith M. Brock ◽  
Max T. Otten
Keyword(s):  
Life Science ◽  
Materials Science ◽  
Chemical Elements ◽  
Full Description ◽  
Scanning System ◽  
Elemental Distribution ◽  
X Ray ◽  
Transmission Electron ◽  
Distribution Of Elements ◽  
Made In

A knowledge of the distribution of chemical elements in a specimen is often highly useful. In materials science specimens features such as grain boundaries and precipitates generally force a certain order on mental distribution, so that a single profile away from the boundary or precipitate gives a full description of all relevant data. No such simplicity can be assumed in life science specimens, where elements can occur various combinations and in different concentrations in tissue. In the latter case a two-dimensional elemental-distribution image is required to describe the material adequately. X-ray mapping provides such of the distribution of elements.The big disadvantage of x-ray mapping hitherto has been one requirement: the transmission electron microscope must have the scanning function. In cases where the STEM functionality – to record scanning images using a variety of STEM detectors – is not used, but only x-ray mapping is intended, a significant investment must still be made in the scanning system: electronics that drive the beam, detectors for generating the scanning images, and monitors for displaying and recording the images.

Research and Application on the Research Innovation Ability of the Graduate Student Based on the Fuzzy Neural Network

2014 ◽  
Vol 687-691 ◽  
pp. 2909-2912 ◽  
Author(s):  
Liang Hu ◽  
Gan Lan Yan ◽  
Long Li
Keyword(s):  
Innovation System ◽  
Scientific Research ◽  
Indicator System ◽  
High Tech ◽  
Design Work ◽  
Independent Innovation ◽  
System A ◽  
Evaluation Models ◽  
Fuzzy Neural ◽  
Innovation Ability

During the course of building an innovative country and enhancing the independent innovation capability, universities are the main force and the important source of high-tech innovation. The evaluation on the university's innovation ability, not only may improve university's efficiency and level of scientific research, but also make a significant sense to perfect the china' scientific research innovation system. Based on Referring to the recent research achievements at home and abroad, research and design work was carried out in the following area. Firstly, the multi-university research innovation ability evaluating indicator system is designed in this paper. By the principle of science and justice, through questionnaires, expert opinion and reference to relevant research results. The paper designed the multi-university's research innovation ability evaluating indicator system. A variety of typical evaluation models and methods are studied. Then two evaluation models between PCA-BP and PCA-FNN are taken into comparison. And the results show that the research and application of PCA-FNN is proved to be a new method and made a significant attempt for the university’s evaluation of research innovation ability.

scholarly journals Relative Abundance and Compositional Variation of Silicates, Oxides and Phosphates in the W-Sn-Rich Lodes of the Panasqueira Mine (Portugal): Implications for the Ore-Forming Process

Minerals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 551 ◽  
Author(s):  
António Mateus ◽  
Jorge Figueiras ◽  
Ivo Martins ◽  
Pedro Rodrigues ◽  
Filipe Pinto
Keyword(s):  
Relative Abundance ◽  
Chemical Nature ◽  
Fault Zones ◽  
Compositional Variation ◽  
Early Cambrian ◽  
Forming Process ◽  
Mineral Deposition ◽  
World Class ◽  
Panasqueira Mine ◽  
Opening And Closing

Panasqueira is a world-class W-Sn-Cu lode-type deposit located in Portugal. It consists of a dense swarm of subhorizontal quartz lodes criss-crossed by several ENE–WSW and N–S fault zones, bordering Late Variscan granite and hosted in Late Ediacaran—Early Cambrian metasediments. The relative abundance and compositional variation (assessed with EPMA) of the main silicates, oxides and phosphates forming the quartz lodes and their margins were examined, aiming to explore: (i) mineral and geochemical zonation at the mine scale; and (ii) some conclusions on the chemical nature of prevalent fluid inflows and T-conditions of mineral deposition. Quartz lodes nearby or far from the known greisen-granite cupola display significant differences, reflecting multiple fluid influxes of somewhat distinct composition related to various opening and closing events extending for several My, ranging from an early “oxide–silicate stage” (OSS) to a “main sulfide stage” (MSS), and further on to a post-ore carbonate stage (POCS); however, a rejuvenation event occurred after MSS. The onset of OSS was placed at ca. 299 ± 5 Ma and the rejuvenation event at ca. 292 Ma. The OSS was confined to ≈500 ≤ T ≤ 320 °C, following rutile and tourmaline growth under ≈640 ≤ T ≤ 540 °C (depending on aSiO2). The rejuvenation event (≈440–450 °C) preceded a late chlorite growth (≈250–270 °C) and the progression towards POCS.

scholarly journals Changes in Halogen (F, Cl, Br, and I) and S Ratios in Rock-Forming Minerals as Monitors for Magmatic Differentiation, Volatile-Loss, and Hydrothermal Overprint: The Case for Peralkaline Systems

Minerals ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 995 ◽  
Author(s):  
Hans G.M. Eggenkamp ◽  
Michael A.W. Marks ◽  
Petya Atanasova ◽  
Thomas Wenzel ◽  
Gregor Markl
Keyword(s):  
Mineral Chemistry ◽  
Hydrothermal Systems ◽  
Fluid Loss ◽  
Volatile Components ◽  
Compositional Variation ◽  
Magmatic Differentiation ◽  
Charge Balance ◽  
Rock Interaction ◽  
Eudialyte Group ◽  
Volatile Loss

We determined the halogen (F, Cl, Br, and I) and sulfur (S) concentrations in Cl-rich rock-forming minerals from five peralkaline complexes. We investigated sodalite (N = 42), eudialyte-group minerals (N = 84), and tugtupite (N = 8) from representative rock samples derived from Ilímaussaq (South Greenland), Norra Kärr (Sweden), Tamazeght (Morocco), Lovozero, and Khibina (Russian Federation). Taken together, sodalite and eudialyte-group minerals dominate the Cl and Br budget of the investigated rocks. For F, however, several other phases (e.g., amphibole, fluorite, villiaumite, and minerals of the rinkite group and the apatite supergroup) are additional sinks, and parts of the S may be scavenged in generally rare sulfides. The investigated minerals contain Cl at the wt.% level, F and S concentrations are in the hundreds to thousands of µg/g-range, Br is less common (0.2–200 µg/g) and I is rare (mostly well below 1 µg/g). Normalized to Cl, sodalite prefers Br relative to eudialyte-group minerals, while F is always enriched in the latter. Our data show that both F and S may represent important components in eudialyte-group minerals, sometimes at similar levels as Cl, which normally dominates. Sulfur reveals redox-dependent behavior: Under reduced crystallization conditions, S is more compatible in eudialyte-group minerals (EGM) than in sodalite, which flips to the opposite under water-rich and presumably more oxidized conditions. We investigate the applicability of F/Cl, Br/Cl, and S/Cl ratios in these minerals in peralkaline systems to better understand the interplay of magmatic differentiation, fluid loss and hydrothermal overprint. Similar to apatite in metaluminous systems, fractionation of sodalite, and eudialyte-group minerals in peralkaline magmas leads to decreasing Br/Cl ratios. The data presented in this study bear implications for the mineral chemistry and compositional variation of sodalite and especially EGM in general. Volatile components in EGM that are not normally considered, such as F and S, can reach concentrations of thousands of µg/g. Especially in the case of F, with its low atomic weight, the results obtained in this study indicate that it is very significant for formulae calculations, neutral charge-balance, and similar aspects at such concentration levels. This study demonstrates that halogen contents and ratios are sensitive monitors for a variety of processes in magmatic-hydrothermal systems, including magmatic fractionation, volatile loss, and fluid–rock interaction.

scholarly journals Li-Distribution in Compounds of the Li2O-MgO-Al2O3-SiO2-CaO System—A First Survey

Metals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1633
Author(s):  
Thomas Schirmer ◽  
Hao Qiu ◽  
Haojie Li ◽  
Daniel Goldmann ◽  
Michael Fischlschweiger
Keyword(s):  
Efficient Solutions ◽  
High Tech ◽  
Compound System ◽  
X Ray Diffraction ◽  
Critical Elements ◽  
System A ◽  
Novel Approach ◽  
Li Ion ◽  
Mechanical Separation ◽  
Pyrometallurgical Processing

The recovery of critical elements in recycling processes of complex high-tech products is often limited when applying only mechanical separation methods. A possible route is the pyrometallurgical processing that allows transferring of important critical elements into an alloy melt. Chemical rather ignoble elements will report in slag or dust. Valuable ignoble elements such as lithium should be recovered out of that material stream. A novel approach to accomplish this is enrichment in engineered artificial minerals (EnAM). An application with a high potential for resource efficient solutions is the pyrometallurgical processing of Li ion batteries. Starting from comparatively simple slag compositions such as the Li-Al-Si-Ca-O system, the next level of complexity is reached when adding Mg, derived from slag builders or other sources. Every additional component will change the distribution of Li between the compounds generated in the slag. Investigations with powder X-Ray diffraction (PXRD) and electron probe microanalysis (EPMA) of solidified melt of the five-compound system Li2O-MgO-Al2O3- SiO2-CaO reveal that Li can occur in various compounds from beginning to the end of the crystallization. Among these compounds are Li1−x(Al1−xSix)O2, Li1−xMgy(Al)(Al3/2y+xSi2−x−3/2y)O6, solid solutions of Mg1−(3/2y)Al2+yO4/LiAl5O8 and Ca-alumosilicate (melilite). There are indications of segregation processes of Al-rich and Si(Ca)-rich melts. The experimental results were compared with solidification curves via thermodynamic calculations of the systems MgO-Al2O3 and Li2O-SiO2-Al2O3.

Evaluation on Environmental Planning of Eco-Industrial Park in China

2013 ◽  
Vol 448-453 ◽  
pp. 259-267 ◽  
Author(s):  
Feng Jin ◽  
Li Zhi Xing
Keyword(s):  
Environmental Planning ◽  
Industrial Ecology ◽  
Technological Development ◽  
Local Economy ◽  
Theory And Practice ◽  
High Tech ◽  
Industrial Park ◽  
System A ◽  
Local Sustainability ◽  
Energy And Material Flows

An Eco-industrial Park (EIP) is an industrial park developed according to the theory of industrial ecology, which can significantly reduce industrial pollution and improve regional or local sustainability. On the account of the requirements on energy and material flows connection, the construction and development of EIPs are contingent for effective environmental plannings. China initiated the construction of EIPs during foundation of the previous economic and technological development or high-tech districts in 2001, by classifying EIPs into 3 categories: Integrated Eco-Industrial Park, Sector Eco-Industrial Park and Venous Industry based on Eco-Industrial Park. In each category, EIP contributes significantly to the regional and local economy as well as regional and sustainable development. The environmental planning for EIP is guided by three independent standards and by the HJT 409-2007 guides for the establishment of EIP Planning, which makes regulations on the principles, methods, contents and detailed requirements of the EIP planning. The purpose of this study is to identify the effectiveness of EIP planning in China. This article reviews the theory and practice of EIPs in China and summarizes Chinas environmental planning (EP) system. A case of EIP is presented for qualitative analysis and for the evaluation of the effectiveness of the EIP planning. The results of the evaluation on both the achievements and the processes of plannings goals, from the perspective of environmental carrying capacity (ECC), reveal the challenges of EIP planning in China. Then recommendations are provided on how to improve Chinas EP system for EIP to achieve the desired results.

To What Extent Do the Investment Programs in the Small and Medium Enterprises Sector Comply with the Determinants of National Competitive Advantage?

2018 ◽  
Vol 1 (1) ◽  
pp. 1-5
Author(s):  
K. M. Anwarul Islam ◽  
Orobah Ali Barghouthi
Keyword(s):  
Competitive Advantage ◽  
Small And Medium Enterprises ◽  
High Tech ◽  
Single Individual ◽  
New Markets ◽  
Local Markets ◽  
Private And Public ◽  
World Class ◽  
Palestinian Economy ◽  
Medium Enterprises

The analysis of the researcher was corroborated by the expert opinion.In the interview researcher said that, the base is small and medium enterprises, the Palestinian economy is dominated by small and medium family-owned businesses: more than 85% of all establishments are owned by a single individual. Private and public shareholder companies and partnerships constitute less than 11% of all firms. The first and most important step is to establish governance in SMS & Establishing partnerships in shape of fund of funds, we have 6 funds, 60 million fund for industry, fund for agriculture, fund for microfinance, fund for Gazza, Jerusalem, fund convertible process, is not money wise but convincing the owners to change the way of working is the most impediment.According to Porter, competitive advantage results from the presence of world- class institutions that first create specialized factors and then continually work to upgrade them. Additional steps to be undertaken according to Mustafa, SMEs widen and open new markets and further invest in local markets and sponsor high-tech industries. The analysis of the researcher was corroborated by the expert opinion.In the interview researcher said that, the base is small and medium enterprises, the Palestinian economy is dominated by small and medium family-owned businesses: more than 85% of all establishments are owned by a single individual. Private and public shareholder companies and partnerships constitute less than 11% of all firms. The first and most important step is to establish governance in SMS & Establishing partnerships in shape of fund of funds, we have 6 funds, 60 million fund for industry, fund for agriculture, fund for microfinance, fund for Gazza, Jerusalem, fund convertible process, is not money wise but convincing the owners to change the way of working is the most impediment.According to Porter, competitive advantage results from the presence of world- class institutions that first create specialized factors and then continually work to upgrade them. Additional steps to be undertaken according to Mustafa, SMEs widen and open new markets and further invest in local markets and sponsor high-tech industries. 

Geochemical and scintillometric characterization and correlation of amethyst geode-bearing Paraná lavas from the Quaraí and Los Catalanes districts, Brazil and Uruguay

2010 ◽  
Vol 147 (6) ◽  
pp. 954-970 ◽  
Author(s):  
LÉO A. HARTMANN ◽  
WILSON WILDNER ◽  
LAUREN C. DUARTE ◽  
SANDRO K. DUARTE ◽  
JULIANA PERTILLE ◽  
...  
Keyword(s):  
Volcanic Rocks ◽  
Field Studies ◽  
Major And Trace Elements ◽  
Strong Variation ◽  
Stratigraphic Sequence ◽  
Stratigraphic Framework ◽  
World Class ◽  
Geochemical Studies ◽  
Bottom To Top ◽  
Aa Lava

AbstractGeochemical studies of the six lowermost lava flows of the Cretaceous Serra Geral Formation (Paraná volcanic province) in Quaraí (Brazil) and Artigas (Uruguay) were combined with flow-by-flow field studies of structures and scintillometric profiles to establish a consistent regional stratigraphic framework over at least 100 km. This greatly improves exploration capability for amethyst and agate geodes. A basalt, colada Mata Olho (Alegrete facies, Serra Geral Formation), was the first lava to flow over the ancient Botucatu desert in the region, but an andesite, colada Catalán, overstepped this basalt in many places, perhaps palaeohighs. Four basaltic andesites complete the lava stratigraphy in this formation, adding up to 300 m of lavas. The stratigraphic sequence of contrasting lava compositions is 51.0 wt% SiO2 in the first lava, followed by 57.5, 52.5, 56.0, 53.0 and finally 54.5 wt% SiO2. Overall MgO variation is between 2 and 7 wt%. All lavas in the two districts are low-Ti (<2.0 wt% TiO2) of the Gramado type. The characteristic contents of most major and trace elements (124 rock samples analysed) allow the ready identification of each lava. Contrasting rock chemistry also results in strong variation in scintillometric values (270 points measured in the field and nineteen continuous borehole profiles); from bottom to top of the stratigraphy, the cps values are 49±3.2, 123±10.3, 62±4.7, 94±4.6, ~45 and ~85. Colada Catalán has the structure of aa lava, particularly the contorted igneous banding and autobreccias in the upper and lower crusts. In some places, a 2 m thick, silicified sandstone layer lies on top of some coladas, and silicified sandstone forms breccias with volcanic rocks. Geochemistry of the six lavas indicates complex evolution, involving melting of lithospheric mantle, injection into the crust and assimilation of crust followed by fractional crystallization. This study indicates the possibility of world-class deposits of amethyst geodes on the Brazilian side of the border with Uruguay.

scholarly journals Detection of Macro and Micro Nutrients in Potatoes using Elemental Analysis Techniques

2020 ◽  
Vol 8 (5) ◽  
pp. 1033-1040
Keyword(s):  
Laser Source ◽  
Elemental Distribution ◽  
X Rays ◽  
Breakdown Spectroscopy ◽  
Fresh Potato ◽  
Fundamental Point ◽  
Nist Database ◽  
Distribution Of Elements ◽  
Laser Induced Breakdown ◽  
Scanned Image

The elemental technique used for the detection of macro and micro nutrients in dry potato and fresh potato has been carried out in this research. Two techniques, namely Laser Induced Breakdown Spectroscopy (LIBS) and Scanning Electron Microscope (SEM) with Energy Dispersive Analysis of X-rays (EDAX) have been employed. LIBS provides the spatial distribution of elements in the considered sample, while SEM with EDAX provide a quantitative percentage of elements in the sample. In the first technique, plasma is created in the sample (dry and fresh potato )when photons emitted from the laser source are impinged on the sample. The elemental distribution in plasma is captured using a spectrometer. Then, with the aid of NIST database, the relationship between wavelength and the intensity of the element is determined and the following observations are made by using origin pro tool. The major macro nutrients detected in the sample are nitrogen, calcium, potassium, phosphorus, and magnesium. The micro nutrients, namely sodium and iron are also detected. In the second technique, the samples are pulverized and placed in the sputtering instrument and scanned by SEM. From the scanned image,the macro and micro nutrient present in the sample are determined. The quantity of the element along with atomic percentage is determined. The investigation was extended to potato based food products, namely lays and potato chips. From the experiment, in addition to the macro and micro nutrient, toxic elements, namely lead and indium present in the sample have also determined. The fundamental point of this examination is to serve the cultivation plants to know the elements of the specific plants.

scholarly journals Geopolitical meridians of world-class universities

2019 ◽  
Vol 89 (10) ◽  
pp. 1012-1023
Author(s):  
Evgeny V. Balatsky ◽  
Natalya A. Ekimova
Keyword(s):  
Professional Associations ◽  
The United States ◽  
Global Market ◽  
International Exchange ◽  
High Tech ◽  
Economic Prerequisite ◽  
World Class ◽  
World Class Universities ◽  
Wide Dissemination

This article discusses results from two waves (2017, 2019) of world-class universities identification, thus allowing provision of a geopolitical snapshot of advanced universities global market. Results show that United Europe is becoming a leader, while Asia and the United States positions have worsened. Economic and cultural factors are based on different countries foundations of success in formation of global universities. The quality of the economic prerequisite involves the existence of global high-tech companies in the country; their number and strength determine the number and strength of world-class universities. The quality of the cultural prerequisite involves wide dissemination of the philosophy of cooperation, that is, intensive national and international exchange experience among universities through creation of numerous collaborations, for example, international leagues and unions, regional consortia and groups, and professional associations and alliances.

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