Kerimasite, {Ca3}[Zr2](SiFe3+2)O12 garnet from the Vysoká-Zlatno skarn, Štiavnica stratovolcano, Slovakia

2015 ◽  
Vol 79 (3) ◽  
pp. 715-733 ◽  
Author(s):  
Pavel Uher ◽  
Stanislava Milovská ◽  
Rastislav Milovský ◽  
Peter Koděra ◽  
Peter Bačík ◽  
...  
Keyword(s):  
Raman Spectrum ◽  
Strong Influence ◽  
Upper Triassic ◽  
Formula Unit ◽  
Porphyry Deposit ◽  
Thermal Metamorphism ◽  
Štiavnica Stratovolcano ◽  
Granodiorite Porphyry ◽  
Porphyry Intrusion ◽  
Internal Vibrations

AbstractKerimasite {Ca3}[Zr2](SiFe23+)O12, a rare member of the garnet supergroup, has been identified in association with andradite–grossular and their hydrated analogues, monticellite, perovskite, clintonite, anhydrite, hydroxylellestadite–fluorellestadite, spinel, magnetite, brucite, valeriite and other minerals from a Ca-Mg skarn in the exocontact of a granodiorite porphyry intrusion in Vysoká-Zlatno Cu-Au skarn-porphyry deposit, the Štiavnica stratovolcano, Central Slovakia. Kerimasite forms euhedral-to-anhedral crystals, 2 to 100 μm across with 0.73–1.62 atoms per formula unit (a.p.f.u.) Zr (16.2–33.6 wt.% ZrO2), 0.34–0.66 a.p.f.u. Ti (4.6–9.3 wt.% TiO2), 0.01 to 0.05 a.p.f.u. Hf (0.4–1.7 wt.% HfO2: the largest Hf content reported in kerimasite), and small amounts of Sn, Sc and Nb (≤0.02 a.p.f.u.). Tetrahedral Si (0.99–1.67 a.p.f.u.; 9.8–18.1 wt.% SiO2) is balanced by 0.85–1.26 a.p.f.u. Fe3+ and by 0.46–0.76 a.p.f.u. Al. The crystals commonly show regular, oscillatory concentric zoning or irregular patchy internal textures due to Zr, Ti, Fe, Al and Si variations during growth or partial alteration and dissolution-reprecipitation. The main substitutions in kerimasite are Y(Fe,Sc)3+ + ZSi4+ = Y(Zr,Ti,Hf,Sn)4+ + Z(Fe,Al)3+ and Ti4+ = Zr4+. Associated andradite locally contains irregular Ti- and Zr-rich zones with ≤11 wt.% TiO2 and ≤4.4 wt.% ZrO2. In comparison with common Ca-rich garnets, the micro-Raman spectrum of kerimasite shows that many bands shift towards much lower wavenumbers, either due to Fe3+ substitution on the Z site or to the strong influence of neighbouring octahedrally-coordinated Zr4+ on internal vibrations of tetrahedra that share oxygens. The formation of kerimasite, monticellite, perovskite and other phases indicate a relatively Ca-rich and Si, Al-poor environment, analogous to other known occurrences of Ca-Zr garnets (Ca-rich skarns and xenoliths, carbonatites). Kerimasite and associated skarn minerals originated during contact-thermal metamorphism of Upper Triassic marl slates with limestone, dolomite, anhydrite and gypsum by Miocene granodiorite porphyry at T ≈ 700°C and P ≈ 50–70 MPa.

Triassic sponges (Sphinctozoa) from Hells Canyon, Oregon

1988 ◽  
Vol 62 (03) ◽  
pp. 419-423 ◽  
Author(s):  
Baba Senowbari-Daryan ◽  
George D. Stanley
Keyword(s):  
Endemic Species ◽  
Upper Triassic ◽  
Island Arc ◽  
Tropical Island ◽  
The Family ◽  
Wallowa Terrane ◽  
Unique Condition ◽  
Hells Canyon

Two Upper Triassic sphinctozoan sponges of the family Sebargasiidae were recovered from silicified residues collected in Hells Canyon, Oregon. These sponges areAmblysiphonellacf.A. steinmanni(Haas), known from the Tethys region, andColospongia whalenin. sp., an endemic species. The latter sponge was placed in the superfamily Porata by Seilacher (1962). The presence of well-preserved cribrate plates in this sponge, in addition to pores of the chamber walls, is a unique condition never before reported in any porate sphinctozoans. Aporate counterparts known primarily from the Triassic Alps have similar cribrate plates but lack the pores in the chamber walls. The sponges from Hells Canyon are associated with abundant bivalves and corals of marked Tethyan affinities and come from a displaced terrane known as the Wallowa Terrane. It was a tropical island arc, suspected to have paleogeographic relationships with Wrangellia; however, these sponges have not yet been found in any other Cordilleran terrane.

Effect of strain on ADF-STEM high-resolution images

1991 ◽  
Vol 49 ◽  
pp. 666-667
Author(s):  
M. Kelly ◽  
D.M. Bird
Keyword(s):  
High Resolution ◽  
Strong Influence ◽  
Intensity Variation ◽  
Dark Field ◽  
Atomic Resolution ◽  
Strain Fields ◽  
High Resolution Image ◽  
Annular Dark Field ◽  
High Resolution Images ◽  
Interesting Alternative

It is well known that strain fields can have a strong influence on the details of HREM images. This, for example, can cause problems in the analysis of edge-on interfaces between lattice mismatched materials. An interesting alternative to conventional HREM imaging has recently been advanced by Pennycook and co-workers where the intensity variation in the annular dark field (ADF) detector is monitored as a STEM probe is scanned across the specimen. It is believed that the observed atomic-resolution contrast is correlated with the intensity of the STEM probe at the atomic sites and the way in which this varies as the probe moves from cell to cell. As well as providing a directly interpretable high-resolution image, there are reasons for believing that ADF-STEM images may be less suseptible to strain than conventional HREM. This is because HREM images arise from the interference of several diffracted beams, each of which is governed by all the excited Bloch waves in the crystal.

Grain separation enhanced magnetic coercivity in Pt/Co multilayers.

1993 ◽  
Vol 51 ◽  
pp. 1038-1039 ◽  
Author(s):  
G.A. Bertero ◽  
R. Sinclair
Keyword(s):  
Remanent Magnetization ◽  
Strong Influence ◽  
Uniaxial Anisotropy ◽  
Magnetic Coupling ◽  
Recording Media ◽  
Magnetic Media ◽  
Signal To Noise ◽  
Out Of Plane ◽  
Longitudinal Recording ◽  
The Relationship

Pt/Co multilayers displaying perpendicular (out-of-plane) magnetic anisotropy and 100% perpendicular remanent magnetization are strong candidates as magnetic media for the next generation of magneto-optic recording devices. The magnetic coercivity, Hc, and uniaxial anisotropy energy, Ku, are two important materials parameters, among others, in the quest to achieving higher recording densities with acceptable signal to noise ratios (SNR). The relationship between Ku and Hc in these films is not a simple one since features such as grain boundaries, for example, can have a strong influence on Hc but affect Ku only in a secondary manner. In this regard grain boundary separation provides a way to minimize the grain-to-grain magnetic coupling which is known to result in larger coercivities and improved SNR as has been discussed extensively in the literature for conventional longitudinal recording media.We present here results from the deposition of two Pt/Co/Tb multilayers (A and B) which show significant differences in their coercive fields.

To β or not to β: A first look at the Raman spectrum of pure β-UO3

2020 ◽  
Author(s):  
Brianna Barth ◽  
Spano Tyler ◽  
Jeremiah Gruidl ◽  
Michael Lance ◽  
Roger Kapsimalis ◽  
...  
Keyword(s):  
Raman Spectrum

The Raman spectrum of solid hydrogen

1965 ◽  
Vol 26 (11) ◽  
pp. 615-620 ◽  
Author(s):  
E.J. Allin ◽  
A.H. M ◽  
V. Soots ◽  
H.L. Welsh
Keyword(s):  
Raman Spectrum ◽  
Solid Hydrogen

RAMAN SPECTRUM OF AgGaS2

1975 ◽  
Vol 36 (C3) ◽  
pp. C3-183-C3-184 ◽  
Author(s):  
D. J. LOCKWOOD ◽  
H. MONTGOMERY
Keyword(s):  
Raman Spectrum

GAS PHASE RAMAN SPECTRUM OF TCNQ AND PRESSURE DEPENDENCE OF THE MODES IN CRYSTALS OF TNCQ°

1981 ◽  
Vol 42 (C6) ◽  
pp. C6-323-C6-325
Author(s):  
C. Carlone ◽  
N. K. Hota ◽  
H. J. Stolz ◽  
M. Elbert ◽  
H. Kuzmany ◽  
...  
Keyword(s):  
Raman Spectrum ◽  
Gas Phase ◽  
Pressure Dependence

Modification of MnS inclusion by tellurium in 38MnVS6 micro-alloyed steel

2020 ◽  
Vol 117 (6) ◽  
pp. 615
Author(s):  
Ping Shen ◽  
Lei Zhou ◽  
Qiankun Yang ◽  
Zhiqi Zeng ◽  
Kenan Ai ◽  
...  
Keyword(s):  
Fatigue Life ◽  
Aspect Ratio ◽  
Strong Influence ◽  
Experimental Results ◽  
Alloyed Steel ◽  
Equivalent Diameter ◽  
Small Aspect Ratio ◽  
Steel Quality ◽  
Eds Analysis ◽  
Micro Alloyed Steel

In 38MnVS6 steel, the morphology of sulfide inclusion has a strong influence on the fatigue life and machinability of the steel. In most cases, the MnS inclusions show strip morphology after rolling, which significantly affects the steel quality. Usually, the MnS inclusion with a spherical morphology is the best morphology for the steel quality. In the present work, tellurium was applied to 38MnVS6 micro-alloyed steel to control the MnS inclusion. Trace tellurium was added into 38MnVS6 steel and the effect of Te on the morphology, composition, size and distribution of MnS inclusions were investigated. Experimental results show that with the increase of Te content, the equivalent diameter and the aspect ratio of inclusion decrease strikingly, and the number of inclusions with small aspect ratio increases. The inclusions are dissociated and spherized. The SEM-EDS analysis indicates that the trace Te mainly dissolves in MnS inclusion. Once the MnS is saturated with Te, MnTe starts to generate and wraps MnS. The critical Te/S value for the formation of MnTe in the 38MnV6 steel is determined to be approximately 0.075. With the increase of Te/S ratio, the aspect ratio of MnS inclusion decreases and gradually reaches a constant level. The Te/S value in the 38MnVS6 steel corresponding to the change of aspect ratio from decreasing to constant ranges from 0.096 to 0.255. This is most likely to be caused by the saturation of Te in the MnS inclusion. After adding Te in the steel, rod-like MnS inclusion is modified to small inclusion and the smaller the MnS inclusion, the lower the aspect ratio.

EMOTIONAL INTELLIGENCE DAN PERILAKU KEPEMIMPINAN PENDIDIKAN ISLAM

2018 ◽  
Vol 2 (2) ◽  
pp. 114-128
Author(s):  
Ahmad Fauzi
Keyword(s):  
Emotional Intelligence ◽  
Strong Influence ◽  
Islamic Education ◽  
Theoretical Level ◽  
Level Of Education ◽  
High Position ◽  
Performance Culture ◽  
And Performance ◽  
Emotional Approach ◽  
High Emotional Intelligence

Sociologically, emotional intelligence is an important part of this study to build leadership social behavior in the management of Islamic education, so that it can color the dynamics of leadership so far and can increase individual loyalty in the organization. Therefore, a leader in mobilizing, motivating and inspiring individuals in the organization requires an emotional approach as a model to awaken individuals in improving their performance culture. Thus the role and actions of leadership in various systems of Islamic education are essentially actualization processes of internalization values inherent in his personality, especially regarding (emotional intelligence). At the theoretical level, emotional intelligence is an important part in building ideal leadership. Portrait of emotional intelligence-based leadership can give birth to two leadership models, including: a) emotional intelligence-based leadership is seen as more effective, and has a strong influence on individual loyalty in Islamic education - even high and low emotional intelligence also affects the high and low loyalty and performance culture. b) the emotional intelligence of a leader cannot be measured by the level of education, even someone's degree. Therefore, it does not guarantee that someone who has a high position or has a high title has high emotional intelligence.

Sign in / Sign up

Export Citation Format

Share Document