scholarly journals ~25 Ma Ruby Mineralization in the Mogok Stone Tract, Myanmar: New Evidence from SIMS U–Pb Dating of Coexisting Titanite

Minerals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 536
Author(s):  
Di Zhang ◽  
Shun Guo ◽  
Yi Chen ◽  
Qiuli Li ◽  
Xiaoxiao Ling ◽  
...  
Keyword(s):  
Chemical Compositions ◽  
Geochronological Data ◽  
The World ◽  
Different Types ◽  
Geochronological Study ◽  
New Evidence ◽  
Secondary Ion ◽  
The Himalaya ◽  
Representative Samples

Ruby (red corundum) is one of the most prominent colored gemstones in the world. The highest-quality ruby (“pigeon blood” ruby) comes from marbles of the Mogok Stone Tract in central Myanmar. Although Mogok ruby has been exploited since the 6th century AD, the formation time of this gemstone is ambiguous and controversial. In this paper, we describe a mineralogical, geochemical, and geochronological study of ruby and titanite in ruby-bearing marbles obtained from an outcrop in the Mogok Stone Tract, central Myanmar. Petrographic observations have shown that titanite generally occurs in the marble matrix or occurs as inclusions in ruby. These two types of titanite exhibit identical chemical compositions. In situ secondary ion mass spectrometer (SIMS) U–Pb dating of the separated titanite from two representative samples of ruby-bearing marbles yielded lower intercept ages of 25.15 ± 0.24 Ma (MSWD = 0.26) and 25.06 ± 0.22 Ma (MSWD = 0.15), respectively. Because the closure temperature of the U–Pb system in titanite is close to the temperature of ruby growth, the obtained U–Pb ages (~25 Ma) are suggested to represent the timing of the studied ruby formation in Mogok. The acquired ages are in agreement with the timing of post-collisional extension in the Himalaya related to the migration of the eastern Himalayan syntaxis. Combining our dating results with previous geochronological data from the Mogok Stone Tract, we suggest that the formation of the studied ruby is most likely related to the high-temperature metamorphic event in the marbles during the India–Asia collision. Our study not only confirms that texturally constrained titanite could be a precise geochronometer to date the mineralization of different types of ruby, but also provides important geochronological information linking gemstone formation to the India–Asia collision.

scholarly journals Herpetological phylogeographic analyses support a Miocene focal point of Himalayan uplift and biological diversification

2020 ◽  
Author(s):  
Wei Xu ◽  
Wen-Jie Dong ◽  
Ting-Ting Fu ◽  
Wei Gao ◽  
Chen-Qi Lu ◽  
...  
Keyword(s):  
Middle Miocene ◽  
Focal Point ◽  
Himalayan Region ◽  
The World ◽  
Early Paleocene ◽  
The Rich ◽  
Source Of Information ◽  
The Himalaya ◽  
Exact Timing

Abstract The Himalaya are among the youngest and highest mountains in the world, but the exact timing of their uplift and origins of their biodiversity are still in debate. The Himalayan region is a relatively small area but with exceptional diversity and endemism. One common hypothesis to explain the rich montane diversity is uplift-driven diversification–that orogeny creates conditions favoring rapid in situ speciation of resident lineages. We test this hypothesis in the Himalayan region using amphibians and reptiles, two environmental sensitive vertebrate groups. In addition, analysis of diversification of the herpetofauna provides an independent source of information to test competing geological hypotheses of Himalayan orogenesis. We conclude that the origins of the Himalayan herpetofauna date to the early Paleocene, but that diversification of most groups was concentrated in the Miocene. There was an increase in both rates and modes of diversification during the early to middle Miocene, together with regional interchange (dispersal) between the Himalaya and adjacent regions. Our analyses support a recently proposed stepwise geological model of Himalayan uplift beginning in the Paleocene, with a subsequent rapid increase of uplifting during the Miocene, finally give rise to the intensification of the modern South Asia Monsoon.

The Oldest Bryozoans: New Evidence From the Late Tremadocian (Early Ordovician) of East Yangtze Gorges in China

2007 ◽  
Vol 81 (6) ◽  
pp. 1308-1326 ◽  
Author(s):  
Feng-Sheng Xia ◽  
Sen-Gui Zhang ◽  
Zong-Zhe Wang
Keyword(s):  
New Species ◽  
North America ◽  
New Genus ◽  
Early Ordovician ◽  
The World ◽  
New Evidence ◽  
New Bryozoans

Previous reports of Cambrian bryozoans have proved not to be bryozoans. No pre-Ordovician bryozoans have been recognized. The oldest unequivocal bryozoans known from North America, Britain, and Russia are evidently of early Arenigian age. New bryozoans recently collected from the Fenxiang Formation in the Daping and Guanzhuangping sections, situated in the area east of the Yangtze Gorges, are described here, including one new genus, Orbiramus, and six new species, Nekhorosheviella nodulifera, N. semisphaerica, Orbiramus normalis, O. ovalis, O. minus, and Prophyllodictya prisca. These are assigned to the Trepostomida, apart from the last species which belongs to the Cryptostomida. The new bryozoans are from the conodont Paltodus deltifer deltifer Zone of the late Tremadocian age, the first three species possibly being present in the P. deltifer pristinus Subzone at the base. Therefore, they are the oldest bryozoans known from anywhere in the world. Extensive reefs resulting from a major regression in the late Tremadocian were dominated by bryozoans in the upper Fenxiang Formation. The bryozoans lived in a shoal environment and accumulated essentially in situ, showing no signs of significant transportation.

The chemical composition and ruminal disappearance of pistachio by-product

2007 ◽  
Vol 2007 ◽  
pp. 224-224 ◽  
Author(s):  
Atiyeh Bohluli ◽  
Abasali Naserian ◽  
Reza Valizadeh
Keyword(s):  
Chemical Composition ◽  
Dry Matter ◽  
Chemical Compositions ◽  
The World ◽  
Physical And Chemical

Iran is the greatest pistachio producer in the world. A large quantity of pistachio by-product (at least 150,000 tons in DM) is produced from pistachio dehulling process in Iran, annually. The results of some experiments show this by¬product can be used as a feedstuff for ruminants (Shakeri and Fazaeli, 2005; VAhmani et. al., 2005). However, more information about physical and chemical compositions of this by-product is needed. Pistachio by-product is mainly consists of epicarp, peduncle, leaf and a little amount of mesocarp and kernel. The aim of this study was to determine chemical composition and in situ dry matter disappearance of each part of pistachio by-product (Ohadi variety) after 0, 12 and 24 h incubation in the rumen.

Characterization of organic monolayers on individual microparticles using microprobe mass spectrometry

1992 ◽  
Vol 50 (2) ◽  
pp. 1710-1711
Author(s):  
Thomas Fister ◽  
John Chakel ◽  
Robert Odom ◽  
Filippo Radicati di Brozolo ◽  
Richard W. Linton
Keyword(s):  
Mass Spectrometry ◽  
Fossil Fuels ◽  
Secondary Ion Mass Spectrometry ◽  
Chemical Transformations ◽  
Organic Monolayers ◽  
Different Types ◽  
Wet Chemical ◽  
Secondary Ion

Polycyclic organic matter (POM) represents a class of compounds of environmental significance. Many of these compounds have been shown to exhibit mutagenic characteristics. POM is formed during the combustion of fossil fuels such as coal. Emitted particulate matter such as coal flyash contains surface associated POM that undergoes chemical transformations due to photolysis and exposure to gaseous pollutants. Past studies of these compounds on flyash have relied on wet chemical techniques in which POM is extracted from large quantities of flyash and then analyzed by chromatography. This technique is hindered by several problems such as the extensive heterogeneity in flyash composition. Individual flyash particles of different composition will influence POM adsorption and reactivity. Studies of the different types of particles by the wet techniques require that the particles be physically separated (density, size, magnetic properties). Microprobe secondary ion mass spectrometry (SIMS) is a technique that can potentially overcome these obstacles by permitting the in situ analysis of POM on single particle surfaces.

Knowledge and Awareness of Dengue Fever

2018 ◽  
pp. 219-222
Author(s):  
Y. Arockia Suganthi ◽  
Chitra K. ◽  
J. Magelin Mary
Keyword(s):  
Dengue Fever ◽  
Prevention And Control ◽  
Control Measures ◽  
Infection Transmission ◽  
Standard Guideline ◽  
The World ◽  
Different Types ◽  
Prevention And Control Measures ◽  
Dengue Prevention ◽  
And Control

Dengue fever is a painful mosquito-borne infection caused by different types of virus in various localities of the world. There is no particular medicine or vaccine to treat person suffering from dengue fever. Dengue viruses are transmitted by the bite of female Aedes (Ae) mosquitoes. Dengue fever viruses are mainly transmitted by Aedes which can be active in tropical or subtropical climates. Aedes Aegypti is the key step to avoid infection transmission to save millions of people in all over the world. This paper provides a standard guideline in the planning of dengue prevention and control measures. At the same time gives the priorities including clinical management and hospitalized dengue patients have to address essentially.

Pb Electrodeposition in the Presence of Chlorine Ions on Cu(100): An in Situ Optical Reflectivity Difference Study

2003 ◽  
Vol 781 ◽  
Author(s):  
J. Gray ◽  
W. Schwarzacher ◽  
X.D. Zhu
Keyword(s):  
Oblique Incidence ◽  
Opposite Sign ◽  
Bulk Phase ◽  
Phase Layer ◽  
Optical Reflectivity ◽  
Scan Rate ◽  
Different Types ◽  
Chlorine Ions ◽  
High Overpotentials

AbstractWe studied the initial stages of the electrodeposition of Pb in the presence of chlorine ions on Cu(100), using an oblique-incidence optical reflectivity difference (OIRD) technique. The OI-RD results reveal that immediately following the underpotential deposition (UPD) of the first Pb monolayer, two different types of bulk-phase films grow depending upon the magnitude of overpotential and cyclic voltammetry (CV) scan rate. At low overpotentials and/or slow scan rates, we propose that a bulk-phase Pb film grows on top of the UPD monolayer. At high overpotentials and/or fast scan rates, either a PbO, PbCl2, or a rough Pb bulk-phase layer grows on top of the UPD layer such that the reflectivity difference signal from such a film has an opposite sign.

Optics-Free Visualization of Proteins in Single Cells by Time of Flight-Secondary Ion Mass Spectrometry Coupled with Genetically Encoded Chemical Tags

2020 ◽  
Author(s):  
Feifei Jia ◽  
Jie Wang ◽  
Yanyan Zhang ◽  
Qun Luo ◽  
Luyu Qi ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Secondary Ion Mass Spectrometry ◽  
Single Cells ◽  
Time Of Flight ◽  
E Coli ◽  
Tof Sims ◽  
Ion Mass Spectrometry ◽  
Chemical Tags ◽  
Secondary Ion

<p></p><p><i>In situ</i> visualization of proteins of interest at single cell level is attractive in cell biology, molecular biology and biomedicine, which usually involves photon, electron or X-ray based imaging methods. Herein, we report an optics-free strategy that images a specific protein in single cells by time of flight-secondary ion mass spectrometry (ToF-SIMS) following genetic incorporation of fluorine-containing unnatural amino acids as a chemical tag into the protein via genetic code expansion technique. The method was developed and validated by imaging GFP in E. coli and human HeLa cancer cells, and then utilized to visualize the distribution of chemotaxis protein CheA in E. coli cells and the interaction between high mobility group box 1 protein and cisplatin damaged DNA in HeLa cells. The present work highlights the power of ToF-SIMS imaging combined with genetically encoded chemical tags for <i>in situ </i>visualization of proteins of interest as well as the interactions between proteins and drugs or drug damaged DNA in single cells.</p><p></p>

Spectro-mechanical Characterization of Aromaticity and Maturity of Kerogens in Oil Shale at 6 nm Spatial Resolution

2018 ◽  
Author(s):  
Devon Jakob ◽  
Le Wang ◽  
Haomin Wang ◽  
Xiaoji Xu
Keyword(s):  
Spatial Resolution ◽  
Oil Shale ◽  
Infrared Imaging ◽  
Mechanical Characterization ◽  
Optical Diffraction ◽  
Chemical Compositions ◽  
Valuable Insight ◽  
Eagle Ford Shale

<p>In situ measurements of the chemical compositions and mechanical properties of kerogen help understand the formation, transformation, and utilization of organic matter in the oil shale at the nanoscale. However, the optical diffraction limit prevents attainment of nanoscale resolution using conventional spectroscopy and microscopy. Here, we utilize peak force infrared (PFIR) microscopy for multimodal characterization of kerogen in oil shale. The PFIR provides correlative infrared imaging, mechanical mapping, and broadband infrared spectroscopy capability with 6 nm spatial resolution. We observed nanoscale heterogeneity in the chemical composition, aromaticity, and maturity of the kerogens from oil shales from Eagle Ford shale play in Texas. The kerogen aromaticity positively correlates with the local mechanical moduli of the surrounding inorganic matrix, manifesting the Le Chatelier’s principle. In situ spectro-mechanical characterization of oil shale will yield valuable insight for geochemical and geomechanical modeling on the origin and transformation of kerogen in the oil shale.</p>

Platón, Einstein y el triunfo de la imaginatividad cosmológica

1998 ◽  
pp. 87-98
Author(s):  
T. M. Robinson
Keyword(s):  
Dynamic Model ◽  
Striking Similarity ◽  
Empirical World ◽  
The World ◽  
Modern Cosmology ◽  
Different Types ◽  
Physical Objects ◽  
Changing World

This article argues the following five claims: 1. Plato’s description of the origins of cosmos in the Timaeus is not a myth, nor something unlikely: when he called it an eikos mythos or eikos logos, he meant a likely or trustworthy account on this very subject. 2. Among the details in this account, the following are prominent and surprising: a) the world was fashioned in time, in that precise point that was the beginning of time; b) several kinds of duration can be distinguished in cosmology (mainly eternity, sempiternity, perpetuity and time); and c) space is an entity characterized by movement and tension. 3. In the Statesman, Plato repeats much the same thing, adding this time the strange notion that the universe’s circular movement is periodically reversed. 4. In spite of the important differences in detail, there is a striking similarity between Plato’s account of the origins of the world and the explanation adopted by much of modern cosmology. 5. What Plato shares with so many instances of recent thought is here termed “cosmological imaginativity”. A first section of the paper deals exclusively with the Timaeus. Claims 1 and 2a are supported by a revision of the meanings of mythos and logos, followed by brief reference and discussion of the argument at Timaeus 27d, leading to the conclusion that Plato affirms that the ever-changing world has indeed had a beginning in time. Claim 2b describes five different types of duration, corresponding to Forms, the Demiurge, Space, the [empirical] world and its contents, physical objects. The second section is concerned with the myth in the Statesman, discussing it as a parallel and describing its peculiar turn to the Timaeus’ cosmology and cosmogony, a complex spheric and dynamic model. After digressing into some important ideas in modern cosmology, touching especially on affinities of some of Einstein’s ideas with of Plato’s own, the paper closes with a discussion of cosmological imaginativity, oriented to recover and recognize fully Plato’s greatness as a cosmologist.

Effective Altruism

2019 ◽  
Keyword(s):  
Animal Welfare ◽  
Poverty Alleviation ◽  
Future Generations ◽  
Global Poverty ◽  
Global Community ◽  
Helping Others ◽  
The World ◽  
Different Types ◽  
Effective Altruism

The effective altruism movement consists of a growing global community of people who organize significant parts of their lives around two key ideas, represented in its name. Altruism: If we use a significant portion of the resources in our possession—whether money, time, or talents—with a view to helping others, we can improve the world considerably. Effectiveness: When we do put such resources to altruistic use, it is crucial to focus on how much good this or that intervention is reasonably expected to do per unit of resource expended (for example, per dollar donated). While global poverty is a widely used case study in introducing and motivating effective altruism, if the ultimate aim is to do the most good one can with the resources expended, it is far from obvious that global poverty alleviation is highest priority cause area. In addition to ranking possible poverty-alleviation interventions against one another, we can also try to rank interventions aimed at very different types of outcome against one another. This includes, for example, interventions focusing on animal welfare or future generations. The scale and organization of the effective altruism movement encourage careful dialogue on questions that have perhaps long been there, throwing them into new and sharper relief, and giving rise to previously unnoticed questions. In the present volume, the first of its kind, a group of internationally recognized philosophers, economists, and political theorists contribute in-depth explorations of issues that arise once one takes seriously the twin ideas of altruistic commitment and effectiveness.

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