Thermal properties of charged dilaton black hole, energy and momentum in teleparallel equivalent of general relativity     

Gamal G. L. Nashed 《Astrophysics and Space Science》2013,344(1):87-97

Two different charged dilaton black holes in 4-dimension, within teleparallel equivalent of general relativity (TEGR), are derived. These solutions are related through local Lorentz transformation. The total energy of these black holes, using three different methods, the Hamiltonian method, the translational momentum 2-form and the Euclidean continuation method given by Gibbons and Hawking, is calculated. It is shown that the three methods give the same results. The value of energy is shown to depend on the mass M and charge q. The verification of the first law of thermodynamics is proved. Finally, it is shown that if the charge q is vanishing then, the total energy reduced to that of Schwarzschild’s black hole.  相似文献   

Evidence for two episodes of volcanism in the Bigadiç borate basin and tectonic implications for western Turkey     

Fuat Erkül  Cahi&#x;t Helvaci  Hasan Szbi&#x;li&#x;r 《Geological Journal》2005,40(5):545-570

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Integrated geo-microbial and trace metal anomalies for detection of hydrocarbon microseepage in Ahmedabad block of Cambay basin,India     

M. A. Rasheed  P. L. Srinivasa Rao  Annapurna Boruah  Syed Zaheer Hasan  Bougi Mohamoud Mohamed Seddik  Disha Pandey  T. Harinarayana 《Journal of the Geological Society of India》2016,88(4):433-439

The aim of the present work is to define the geo-microbial signatures along with trace metals, and to investigate whether the geo-microbial anomalies have correlation with trace metal anomalies in Ahmedabad block of Cambay basin. The surface geochemical techniques are based on seepage of light hydrocarbon gases from the oil and gas pools to the shallow surface and can bring up near-surface oxidation reduction zones that favor the development of a diverse array of chemical and mineralogical changes. The paper reports the role of hydrocarbon microseepage in surface alterations of trace metal concentrations and hydrocarbon oxidizing bacteria and its interrelationship. For the purpose a total of 90 soil samples are collected in grid pattern of 2 x 2 km interval. The paper reports the chemical alterations associated with trace metals in soils that are related to hydrocarbon microseepages above some of the major oil and gas fields of this petroliferous region. The concentrations of V (0 to149 ppm), Cr (2 to 192 ppm), Cu (4 to 171 ppm), Se (98 to 440 ppm), Zn (56 to 1215 ppm) are obtained. It is observed that the concentrations of trace elements are tremendously increased when they are compared with their normal concentrations in soils. In this study the hydrocarbon oxidizing bacterial counts ranged between 1.0 x 10³ and 1.59 x 10⁶ cfu/g of soil sample respectively. The attempt has made for the first time, which revealed good correlation as both these anomalies are found as apical in relation. Integrated studies between trace elements and hydrocarbon oxidizing bacterial anomalies showed positive correlation with existing oil and gas wells in the study area.  相似文献   

Assessment of backbreak due to blasting operation in open pit mines: a case study     

Ebrahim Ghasemi  Hasan Bakhshandeh Amnieh  Raheb Bagherpour 《Environmental Earth Sciences》2016,75(7):552

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Chemical fractionation,mobility and environmental impacts of heavy metals in greenhouse soils from Çanakkale,Turkey     

Ali Sungur  Mustafa Soylak  Hasan Özcan 《Environmental Earth Sciences》2016,75(4):334

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Comparative study of haematological, serum electrolyte and nonelectrolyte parameters of male and female Persian sturgeon (Acipenser persicus) brood stocks     

ADEL Mil  PALANISAMY Satheesh Kumar  SHAFIEI Shafigh  FAZLI Hasan  ZORRIEHZAHRA Mohammad Jalil 《海洋学报(英文版)》2016,35(8):39-43

Sturgeons are the most important principal market species in the Caspian Sea. In the present study, measurement of blood parameters was carried out with the aim of evaluating the normal value of hematological and serum biochemical parameters of brood stocks Acipenser persicus during spawning season. Blood samples were collected from 36 brood stocks of A. persicus (18 males and 18 females) during the spawning season. Higher value of red blood cells, white blood cells, haemoglobin, haematocrit was observed in male breeders with significant differences between female breeders (p>0.05). Haemoglobin and haematocrit value in this study was within the range of 8.70 to 9.2 g/dL and 29.73% to 30.26%, respectively. The statistically significant differences between mean corpuscular volumes, mean corpuscular haemoglobin, lymphocyte and neutrophil percentages, aspartate aminotransferase, alkaline phosphatase and creatine kinase were observed in the male and female brood stocks. It is concluded from this study, some of the hematological and serum biochemical parameters of male and female A. persicus breeders were significantly varied from each other. In comparative investigation with earlier reports, the values of red blood cells, haemoglobin and haematocrit are highly varied due to age variations of fish. However, further studies are necessary to understand the impact of sexual, age, size, length, and season and habitat variation. Serum biochemical parameters can be used for confirming the maturity of A. persicus and monitoring any changes in the water quality parameters and soil.  相似文献   

Palaeoseismology of the Havran-Balıkesir Fault Zone: evidence for past earthquakes in the strike-slip-dominated contractional deformation along the southern branches of the North Anatolian fault in northwest Turkey     

Hasan Sözbilir  Çağlar Özkaymak  Bora Uzel  Ökmen Sümer  Semih Eski  Çiğdem Tepe 《Geodinamica Acta》2016,28(4):254-272

The Havran-Bal?kesir Fault Zone (HBFZ) is one of the major active structures of the Southern Marmara Region, which has been shaped by the southern branch of North Anatolian fault since the Pliocene. HBFZ is a 10–12 km wide, 120 km long, right-lateral strike-slip fault zone that consists of two ENE-striking main faults, namely, the Havran-Balya and Bal?kesir faults. The 90-km-long Havran-Balya fault exhibits right-stepping en echelon geometry and is made up of (1) Havran, (2) Osmanlar, (3) Turplu and (4) Ovac?k fault segments. On the eastern part, the 70-km-long Bal?kesir fault is divided into two fault segments; (1) Gökçeyaz? and (2) Kepsut. We estimated the long-term slip rate between 3.59 and 3.78 mm/yr using river offset. The Kepsut, Gökçeyaz? and Ovac?k fault segments are capable of generating an earthquake with a moment magnitude of up to 7.2. Detailed palaeoseismological studies show that the HBFZ is responsible for some surface faulting earthquakes with an average recurrence interval of 1000–2000 years during the late Holocene. Considering the fact that there was no evidence of a surface-ruptured earthquake for 2000 years, it can be stated that there is a seismic gap on the Gökçeyaz? fault segment.  相似文献   

GIS-based approach for flood analysis: case study of Keçidere flash flood event (Turkey)     

Isa Curebal  Recep Efe  Hasan Ozdemir  Abdullah Soykan  Süleyman Sönmez 《国际地球制图》2016,31(4):355-366

The purpose of this study is to explain the formation mechanism of the floods which occurred in the Keçidere basin in 2009. In this study, discharge data in between 1981 and 2009, digital elevation model (DEM), satellite images and field works were used as a main data sources. LPT3 was applied to 29-year maximum flow data to produce different flood return periods such as 2, 5, 50, 100, 200, 500 and 1000-year flood. The DEM was created using 1:25,000 topographic contours with Topo to Raster interpolation techniques in geographical information systems (GIS). Land use and some geometric data were digitized using high resolution satellite images for hydraulic modelling purposes. Simulation of the 2009 flash flood event and different return periods flow data was done using one-dimensional hydraulic modelling with HEC-RAS. In the last phase, results obtained from the simulations and field works were compared based on fits statistics and mean absolute error in terms of extent and depth. An analysis of water extent and depth features observed during the highest flow ever measured in the basin revealed that the result overlapped with 500-year inundation extent. Overall, the results of the research indicate that GIS is an effective environment for floodplain mapping and analysis.  相似文献   

Optical and photometric studies of Earth orbiting small space objects     

I. M. Selim  Afaf M. Abd El-Hameed  N. S. Bakhtigaraev  Gamal F. Attia 《Astronomy Reports》2016,60(3):374-388

Variations of light curves for space objects are investigated. Optical observations and photometric measurements for small space debris on highly elliptical orbits (HEO) and geostationary orbits (GEO) are used to determine their orbital parameters. Light curves of small space debris with various area-to-mass ratios and orbital characteristics are discussed. Tracking of some objects shows very rapid brightness variations related to perturbations of the orbital parameters. Changes in brightness and equatorial coordinates of the studied objects are found in observational data. Our results allow improving the accuracy of space debris orbital elements.  相似文献   

Using multiple-accumulator CMACs to improve efficiency of the X part of an input-buffered FX correlator     

Stepan Lapshev  S. M. Rezaul Hasan 《Experimental Astronomy》2017,43(2):177-187

This paper presents the approach of using complex multiplier-accumulators (CMACs) with multiple accumulators to reduce the total number of memory operations in an input-buffered architecture for the X part of an FX correlator. A processing unit of this architecture uses an array of CMACs that are reused for different groups of baselines. The disadvantage of processing correlations in this way is that each input data sample has to be read multiple times from the memory because each input signal is used in many of these baseline groups. While a one-accumulator CMAC cannot switch to a different baseline until it is finished integrating the current one, a multiple-accumulator CMAC can. Thus, the array of multiple-accumulator CMACs can switch between processing different baselines that share some input signals at any moment to reuse the current data in the processing buffers. In this way significant reductions in the number of memory read operations are achieved with only a few accumulators per CMAC. For example, for a large number of input signals three-accumulator CMACs reduce the total number of memory operations by more than a third. Simulated energy measurements of four VLSI designs in a high-performance 28 nm CMOS technology are presented in this paper to demonstrate that using multiple accumulators can also lead to reduced power dissipation of the processing array. Using three accumulators as opposed to one has been found to reduce the overall energy of 8-bit CMACs by 1.4% through the reduction of the switching activity within their circuits, which is in addition to a more than 30% reduction in the memory.  相似文献