scholarly journals Comparative Characteristics of Structural-Textural, Mineralogical and Petrochemical Features of Melt Rock Impactites of the Kara Astrobleme. Preliminary Data (Pay-Khoy, Russia)

2021 ◽  
Vol 906 (1) ◽  
pp. 012020
Author(s):  
Alexandr Zubov ◽  
Tatyana Shumilova
Keyword(s):  
High Temperature ◽  
Preliminary Data ◽  
Fundamental Problem ◽  
River Mouth ◽  
Ultrahigh Pressure ◽  
Time Interval ◽  
Impact Melt ◽  
Reported Study ◽  
The Difference ◽  
The Impact

Abstract The Kara astrobleme is one of the largest astroblemes known on land. Its diameter is ~65 km, the age is about 70 million years. The astrobleme is located at the northeastern part of the Pay-Khoy anticlinorium at the Kara River mouth region (Kara Sea coast, Russia). It is a unique object of impact genesis due to the presence of a variety of suevites and melt impactites. Melt rocks are products of the highest degree of impact transformation of target rocks. The diversity of melt rock impactites of the Kara astrobleme and obtaining their complex comparative mineralogical and petrochemical characteristics are important for solving the fundamental problem for studying of the typomorphism of the impactitogenesis products of melt rocks both – the impactites of the Kara astrobleme and other astroblemes in general. In the Kara astrobleme region there are at list two different types of massive melt rocks bodies – a cover melt rock at the Anaroga River (I) studied by previous researchers and an unexplored body of melt rock impactite at the Kara River (II) spatially connected with ultrahigh-pressure high-temperature (UHPHT) glasses just recently discovered. Our preliminary data indicate that the melt rock varieties of the Kara astrobleme have significant differences in texture and structure. The considered melt rocks are mostly composed of a matrix represented by a “mixture” of amorphous and cryptocrystalline masses of predominantly feldspar composition with a subordinate SiO2 content. According to the data of energy dispersive analysis the compositions of the studied melt rocks are similar and have minor deviations within the first percent. The difference in the shape of silicate segregations in melt rocks may indicate that the impact melt could have a high temperature with a shorter time interval for the solidification of melt rock II on the Kara River, in contrast to the massive melt rock I on the Anaroga River, where the impact melt had large volume and, accordingly, was cooled longer at lower temperatures. The data obtained complement the specificity of the Kara melt impactites, which may play a role in complementing the geological model of the Kara astrobleme. The reported study was funded by RFBR, project number 20-35-90065; the analytical equipment has been used at the Center for Collective Use “Geonauka” (IG Komi FRC SC UB RAS, Syktyvkar, Russia); the author expresses his gratitude to Isaenko S.I. for analytical work using Raman spectroscopy; Tropnikov E.M. for help in performing microprobe studies.

scholarly journals Analysis of Impact of Aral Sea Catastrophe on Anomaly Climate Variables and Hydrological Processes

2021 ◽  
pp. 65-74
Author(s):  
T. Berdimbetov ◽  
S. Nietullaeva ◽  
A. Yegizbayeva
Keyword(s):  
Climate Change ◽  
Global Climate ◽  
Aral Sea ◽  
Hydrological Processes ◽  
Time Interval ◽  
Climate Data ◽  
Ambient Temperatures ◽  
The Difference ◽  
Normal Trend ◽  
The Impact

Since 1960, water level began to decline considerably due to anthropogenic impact of the Aral Sea (AS), and it is continued to this day, which has led to dramatic changes in the climate around the AS, including ambient temperatures and sharp increases in evapotranspiration. Although, it isn't possible to see normal trend in this precipitation. Time series analysis of the FTI (First Time Interval 1901-1960) and STI (Second Time Interval, 1960-2015), highlighting climate change around the AS, based on Global Climate Data, suggests that there is a significant negative difference between precipitation and evapotranspiration during the drying of the AS. It is possible to see the logical compatibility of the air temperature and difference between precipitation and evapotranspiration observed around the AS, i.e. the temperature fluctuation trend is positive and contrary to the difference between precipitation and evapotranspiration negative trend, which means that the annual hydrological budget was reduced according to the time scale. In this article, determining the AS as the central point, we analyze the changes in the thermal and hydrological processes observed on the AS, as well as the impact to the environment of anomalous climate change observed on and around the sea like the drying out of the AS.

scholarly journals NMR Spectral Characteristics of Ultrahigh Pressure High Temperature Impact Glasses of the Giant Kara Crater (Pay-Khoy, Russia)

Minerals ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1418
Author(s):  
Vladimir Lyutoev ◽  
Tatyana Shumilova ◽  
Anton Mazur ◽  
Peter Tolstoy
Keyword(s):  
High Pressures ◽  
Spectral Characteristics ◽  
Glass Network ◽  
Mas Nmr ◽  
Ultrahigh Pressure ◽  
Impact Melt ◽  
Partial Melt ◽  
Natural Glass ◽  
Pressure Impact ◽  
The Impact

In this study, we carried out the analysis of the impact melt vein glasses from the Kara impact crater (Russia) in comparison to low-pressure impact melt glasses (tektites) of the Zhamanshin crater (Kazakhstan). 27Al, 23Na, and 29Si MAS NMR spectra of the samples of these glasses were analyzed. The samples of the natural glass contained inclusions of crystalline phases, paramagnetic elements that greatly complicate and distort the NMR signals from the glass phase itself. Taking into account the Mossbauer distribution of Fe in these glasses, the analysis of the spectra of MAS NMR of glass network-former (Si, Al) and potential network-modifiers (Na) of nuclei leads to the conclusion that the Kara impact melt vein glasses are characterized by complete polymerization of (Si,Al)O4 tetrahedral structural units. The NMR features of the glasses are consistent with the vein hypothesis of their formation under conditions of high pressures and temperatures resulting in their fluidity, relatively slow solidification with partial melt differentiation, polymerization, and precipitation of mineral phases as the impact melt cools. The 70 Ma stability of the Kara impact vein glass can be explained by the stabilization of the glass network with primary fine-dispersed pyroxene and coesite precipitates and by the high polymerization level of the impact glass.

Reader expertise and the literary significance of small-scale textual features in prose fiction

2019 ◽  
Vol 9 (1) ◽  
pp. 3-33 ◽  
Author(s):  
Fabio Parente ◽  
Kathy Conklin ◽  
Josephine Guy ◽  
Gareth Carrol ◽  
Rebekah Scott
Keyword(s):  
Eye Tracking ◽  
Attention Allocation ◽  
Small Scale ◽  
Time Interval ◽  
Prose Fiction ◽  
Textual Features ◽  
The Difference ◽  
The Impact ◽  
Effect Experiment ◽  
Difference Effect

Abstract We use eye tracking to investigate the attention readers pay to different textual features to determine their significance in the appreciation of prose fiction. Previous research examined attention allocation to lexical and punctuation variants, and the impact on reading dynamics for the remainder of the text, demonstrating that readers notice both kinds of variants but assign less value to the latter (Carrol, Conklin, Guy, & Scott, 2016). Here, in two experiments, we examine two conditions that may affect attention allocation: We investigate the influence of reader expertise (Experiment 1) and whether performance is influenced by a task-specific “spot-the-difference” effect (Experiment 2). We found that expertise plays little role in readers’ greater sensitivity to lexical rather than punctuation changes, and that the advantage for lexical changes persisted when the time interval between exposures is increased. These results confirm earlier findings: that small-scale features may not possess the creative significance predicated of them by critics and text-editors.

A Novel and Comprehensive Study of Polymeric and Traditional Phosphonate Inhibitors for High-Temperature Scale Control

SPE Journal ◽  
2013 ◽  
Vol 18 (03) ◽  
pp. 575-582 ◽  
Author(s):  
Wei Wang ◽  
Amy T. Kan ◽  
Mason B. Tomson
Keyword(s):  
High Temperature ◽  
Thermal Degradation ◽  
Oil And Gas ◽  
Gas Production ◽  
Oil And Gas Production ◽  
The Difference ◽  
Scale Control ◽  
The Impact ◽  
Thermal Stability Of ◽  
Comprehensive Study

Summary A novel barite-inhibition assay based on the nucleation and inhibition model has been proposed and used to evaluate the thermal stability of phosphonates and polymeric scale inhibitors with regard to their potential application in high-temperature wells. Systematic experiments have been conducted to investigate the time (minutes to days) and temperature (up to 200°C) dependence of inhibitor thermal degradation, the impact of stainless steel and iron on the degradation of inhibitors at high temperatures, and the difference between aging tests with inhibitors in solution and with those inhibitors adsorbed on core materials. The results not only enable a more accurate understanding of the thermal degradation of scale inhibitors but also facilitate the selection and placement of scale inhibitors for high-temperature oil and gas production.

Numerical Simulation of Impact Process of Coal and Gangue

2011 ◽  
Vol 189-193 ◽  
pp. 953-957 ◽  
Author(s):  
Hao Jiang ◽  
Chang Long Du ◽  
Song Yong Liu ◽  
Jia Jia Zhang ◽  
Fei Liu
Keyword(s):  
Material Properties ◽  
Time Course ◽  
Fundamental Problem ◽  
Pressure Variation ◽  
Impact Point ◽  
Impact Process ◽  
Finite Element Software ◽  
Simulation Results ◽  
The Difference ◽  
The Impact

The difference of forcing status between coal and gangue in the process of impact was a fundamental problem in separation of them. In order to finding out forcing status of coal and gangue, the impact process was emulated by finite element software. The variation curves of contact force, the time-course curves of stress and pressure at different locations on material and board hammer were gained. The simulation results showed that for the different material properties, stress and pressure variation of coal were less than gangue, and the impact point in board hammer has the worst forcing status.

scholarly journals Impact-Initiation Sensitivity of High-Temperature PTFE-Al-W Reactive Materials

Crystals ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 30
Author(s):  
Tao Sun ◽  
Yuanfeng Zheng ◽  
Ying Yuan ◽  
Haifu Wang
Keyword(s):  
High Temperature ◽  
Temperature Interval ◽  
High Speed ◽  
Sample Temperature ◽  
Initiation Mechanism ◽  
Reactive Materials ◽  
Impact Initiation ◽  
The Difference ◽  
Sensitivity Changes ◽  
The Impact

Drop-weight tests were conducted to investigate the impact-initiation sensitivity of high-temperature PTFE-Al-W reactive materials. The test results show that the impact-initiation sensitivity of the materials more than doubles with increasing the sample temperature from 25 to 350 °C. Combined with the impact-induced initiation process recorded by high-speed video and the difference between reacted and unreacted residues, the crack-induced initiation mechanism was revealed. The rapid propagation of crack provides a high-temperature and aerobic environment where Al reacts violently to PTFE, which induces the initiation. Moreover, the influence of sample temperature on the sensitivity was discussed and analyzed. The analysis results indicate that the sensitivity shows a temperature interval effect, and 127 and 327 °C are the interval boundaries where the sensitivity changes significantly. The sensitivity may leaps at 127 °C and increases more rapidly in the temperature interval from 127 to 327 °C, but hardly changes after the temperature reaches 327 °C.

Evaluation of the impact of public investment programs on social and economic performance of territories

2019 ◽  
pp. 109-123
Author(s):  
I. E. Limonov ◽  
M. V. Nesena
Keyword(s):  
Bayesian Modeling ◽  
Positive Impact ◽  
Public Investment ◽  
Difference In Differences ◽  
The Public ◽  
Export Activity ◽  
Regional Investment ◽  
The Difference ◽  
The Impact ◽  
Development Institution

The purpose of this study is to evaluate the impact of public investment programs on the socio-economic development of territories. As a case, the federal target programs for the development of regions and investment programs of the financial development institution — Vnesheconombank, designed to solve the problems of regional development are considered. The impact of the public interventions were evaluated by the “difference in differences” method using Bayesian modeling. The results of the evaluation suggest the positive impact of federal target programs on the total factor productivity of regions and on innovation; and that regional investment programs of Vnesheconombank are improving the export activity. All of the investments considered are likely to have contributed to the reduction of unemployment, but their implementation has been accompanied by an increase in social inequality.

The Use of Multimedia and its Impact on Bangladeshi EFL Learners at Tertiary Level

2020 ◽  
Vol 4 (2) ◽  
pp. 150
Author(s):  
Farzana Sharmin Pamela Islam
Keyword(s):  
Language Learning ◽  
Academic Writing ◽  
Teaching And Learning ◽  
English Language ◽  
Capital City ◽  
Tertiary Level ◽  
Language Classroom ◽  
The Difference ◽  
The Government ◽  
The Impact

As 21st century is the era of modern technologies with different aspects, it offers us to make the best use of them. After tape recorder and overhead projector (OHP), multimedia has become an important part of language classroom facilities for its unique and effective application in delivering and learning lesson. Although in many parts of Bangladesh, a South Asian developing country, where English enjoys the status of a foreign language, the use of multimedia in teaching and learning is viewed as a matter of luxury. However, nowadays the usefulness and the necessity of it are well recognized by the academics as well as the government. The study aims to focus on the difference between a traditional classroom void of multimedia and multimedia equipped classrooms at university level by explaining how multimedia support the students with enhanced opportunity to interact with diverse texts that give them more in-depth comprehension of the subject. It also focuses on audio-visual advantage of multimedia on the students’ English language learning. The study has followed a qualitative method to get an in-depth understanding of the impact of using multimedia in an English language classroom at tertiary level. For this purpose, the data have been collected from two different sources. Firstly, from students’ written response to  an open ended question as to their comparative experience of learning  lessons with and without multimedia facilities; and secondly, through  observation of English language classes at a private university of Dhaka, the capital city of Bangladesh. The discussion of the study is limited to  the use of multimedia in English language classroom using cartoons, images and music with a view to enhance students’ skills in academic writing, critical analysis of image and critical appreciation of music. For this purpose, cartoons in English language, images from Google and music from You Tube have got focused discussion in this paper.

Case study: Prediction and field tests of railway noise and effects of a low-height noise barrier

2020 ◽  
Vol 68 (4) ◽  
pp. 303-314
Author(s):  
Yuna Park ◽  
Hyo-In Koh ◽  
University of Science and Technology, Transpo ◽  
University of Science and Technology, Transpo ◽  
University of Science and Technology, Transpo ◽  
...  
Keyword(s):  
High Speed ◽  
Field Tests ◽  
Residential Areas ◽  
Railway Systems ◽  
Railway Noise ◽  
Sound Levels ◽  
Noise Barrier ◽  
The Difference ◽  
Reduction Effect ◽  
The Impact

Railway noise is calculated to predict the impact of new or reconstructed railway tracks on nearby residential areas. The results are used to prepare adequate counter- measures, and the calculation results are directly related to the cost of the action plans. The calculated values were used to produce noise maps for each area of inter- est. The Schall 03 2012 is one of the most frequently used methods for the production of noise maps. The latest version was released in 2012 and uses various input para- meters associated with the latest rail vehicles and track systems in Germany. This version has not been sufficiently used in South Korea, and there is a lack of standard guidelines and a precise manual for Korean railway systems. Thus, it is not clear what input parameters will match specific local cases. This study investigates the modeling procedure for Korean railway systems and the differences between calcu- lated railway sound levels and measured values obtained using the Schall 03 2012 model. Depending on the location of sound receivers, the difference between the cal- culated and measured values was within approximately 4 dB for various train types. In the case of high-speed trains, the value was approximately 7 dB. A noise-reducing measure was also modeled. The noise reduction effect of a low-height noise barrier system was predicted and evaluated for operating railway sites within the frame- work of a national research project in Korea. The comparison of calculated and measured values showed differences within 2.5 dB.

A NEW WELDING MATERIAL FOR REGENERATION IN THE WELDING TECHNOLOGY BASED ON NICKEL. ANALYSIS OF THE COMPOSITION AND PROPERTIES OF DEFORMABLE HEAT-RESISTANT HIGH-CHROMIUM NICKEL-BASED ALLOYS FOR WELDED PARTS. ANALYSIS OF EXISTING FUELLING STATIONS TYPES AND VEHICLES USING HYDROGEN, HYDROGEN PRODUCTION AND STORING METHODS

2019 ◽  
pp. 43-48
Author(s):  
Ben Nengjun ◽  
Zhou Pengfei ◽  
Oleksandr Labartkava ◽  
Mykhailo Samokhin
Keyword(s):  
Rare Earth ◽  
High Temperature ◽  
Nickel Alloys ◽  
Total Content ◽  
Operating Conditions ◽  
High Temperature Strength ◽  
High Chromium ◽  
Salt Corrosion ◽  
Tcp Phases ◽  
The Impact

This work involves an analysis of high-chromium high-temperature deformable wieldable nickel alloys for use in GTE repair assemblies. It is shown that the alloys EP868 (VZh98) and Haynes 230 can be used in welded assemblies with an operating temperature of 800-1100 °C. The alloys Nimonic 81, Nimonic 91, IN 935, IN 939, and Nicrotan 2100 GT also have a high potential for use in welded assemblies. They are characterized by a combination of good weldability, high-temperature strength, and resistance to scaling. There have been conducted studies on high-temperature salt corrosion of model nickel alloys. They allowed establishing the patterns of the impact of base metal alloying with chromium, aluminum, titanium, cobalt, tungsten, molybdenum, niobium, tantalum and rare earth metals on the critical temperature of the start of salt corrosion Tcor and the alloy mass loss. It has been established that alloys with a moderate concentration (13-16%) of chromium can possess satisfactory hightemperature corrosion resistance (HTC resistance) under the operating conditions of ship GTE. The HTC resistance of CrAl-Ti alloys improves upon reaching the ratio Ti/Al ˃ 1. Meanwhile, the ratio Ti/Al ˂ 1 promotes the formation of corrosion products with low protective properties. The positive effect of tantalum on the HTC resistance of alloys is manifested at higher test temperatures than that of titanium, and the total content of molybdenum and tungsten in alloys is limited by the condition 8Mo2 – 2W2 = 89. The presence of refractory elements stabilizes the strengthening phase and prevents formation of the ɳ-phase. However, their excess promotes formation of the embrittling topologically close packed (TCP) phases and boundary carbides of an unfavorable morphology. Based on the studies of the HTC resistance, there has been identified a class of model high-temperature corrosionresistant nickel alloys with a moderate or high chromium content (30%), Ti/Al ˃ 1, and a balanced content of refractory and rare-earth elements.

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