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111.
In this paper we present the observations of the eclipsing binary LX Per, which were obtained in 1983. There is a wave-like distortion at outside eclipses with an amplitude ranging from 0.03 to 0.08 mag. The wave-like distortion was removed with a new approach. Then, the light curves were analyzed by the methods of Wood and Nelson, Davis, and Etzel. The absolute parameters of the components were also calculated. The physical parameters of the components indicate that the cooler star has seperated or has been departing from the Main Sequence. 相似文献
112.
Gökhan Göktürkler Çağlayan Balkaya Zülfikar Erhan Ayça Yurdakul 《Environmental Geology》2008,54(6):1283-1290
Near-surface geophysical methods are commonly used to solve a wide class of geological, engineering and environmental problems. In this study, a geoelectrical survey was performed to investigate an alluvial aquifer. The study area is located in the southwest of the Çubukluda? graben, situated in the south of ?zmir, Turkey. The geophysical studies included the electrical resistivity imaging and self-potential (SP) methods. The resistivity data were acquired along eight profiles in the northern part of the study area by a Wenner-Schlumberger electrode configuration and the data processing was achieved by a tomographic inversion technique. The SP data were collected by gradient technique along 16 profiles. Total field values were calculated for each profile by addition of the successive gradient values, then a total field SP map was obtained. The water-saturated zone in the northern part of the study area was clearly revealed by the electrical resistivity imaging and the SP survey yielded useful information on the subsurface fluid movement. 相似文献
113.
114.
Using the archival ROSAT PSPC observations, AB Dor is found to be variable in X-rays. The periodic variations are consistent with previously reported rotational period of 0
d
.514. The average spectrum of AB Dor is best represented with two-temperature Raymond-Smith model with kT values of 0.19±0.07 and 1.17±0.02 keV. The quiescent luminosity of the system is found to be 4.36±0.6×1030 ergs s–1. A flare with a rise time of 350 seconds is detected during which X-ray luminosity rises from 5.8±1.6×1030 to 15.8±4.9×1030 ergs s–1. We conclude that AB Dor is very similar to the active components of RS CVn binaries and other active classes. In view of the wide separation from the binary companion Rst 137B, this activity must be intrinsic to the active star. 相似文献
115.
Cappadocia is essentially covered by nine rhyolitic ignimbrite units, being the products of a multi-phase volcanism of Upper Miocene-Pliocene age. Around Ürgüp and the Kizilirmak River, these ignimbrites constitute a volcanic-sedimentary succession together with lacustrine sediments, called the Ürgüp formation. In the zeolite occurrences of Cappadocia that were found in the lacustrine parts of pyroclastics outcropping around the Tuzköy, Sarihidir, Karain, Çökek, Ibrahim Pasa and Karadag areas, clinoptilolite is the most common mineral and is associated with chabazite, erionite and phillipsite in some areas. A gain of alkaline-earths from the lake water, which is compensated by a loss of alkalis from the glass, took place during the formation of the different zeolite assemblages, which were probably controlled by the composition of the parent glasses. The distribution of erionite confirms its relation with mesothelioma cases in Tuzköy, Sarihidir and Karain villages that are located outside tourist areas. The high incidence of malignant mesothelioma in Karain may be explained by uncontrolled occupational exposure to erionite. The fairy chimneys, canyons and underground cities, which are situated in the unaltered or slightly altered parts of the Kavak, Zelve, Cemilköy, Gördeles and Kizilkaya ignimbrites do not constitute any health risk for the inhabitants or for visitors. 相似文献
116.
117.
N. Güler Dincer M. Oğuzhan Yalçin 《International Journal of Environmental Science and Technology》2016,13(12):2927-2938
Air pollution monitoring networks are the primary tools for measuring, managing and assessing air quality. However, these networks need considerable financial resources due to expensive devices and analyses, as well as such issues as the likely redundancy in the number of samples. The primary objective of this study was to identify possible information and equipment redundancies in Turkish monitoring networks. Thus, it is expected that the results of this study may help reduce air pollution monitoring expenses and increase monitoring efficiency. For this purpose, the Fuzzy C-Means clustering algorithm and time series analyses were used. This study has two novelties. First, this is the first study to be conducted for this purpose in Turkey. Further, Dickey–Fuller test statistics and model parameters have not been used as clustering variables before. Thus, it is expected that both stochastic behavior and concentration levels of PM10 time series will be reflected simultaneously, and similarities among monitoring stations will be better identified. 相似文献
118.
119.
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
120.
Turbidites and their association with past earthquakes in the deep Çınarcık Basin of the Marmara Sea
Two gravity cores (CAG-3 and C-15) from the tectonically active, 1,276-m deep Çınarcık Basin of the Marmara Sea each include three sandy turbiditic mud units (1 mm–2 cm thick) with sharp basal contacts. The high benthic foraminifer content of these units suggests that the sediments were transported by turbidity currents from the upper slope region. These units represent the thin edges of turbidites thickening towards the subsiding north-eastern part of the basin, and contain quartz, detrital calcite, intact shells and shell fragments, smectite, pyrite framboids, muscovite, biotite, epidote and garnet. Their clay fractions are more enriched in smectite than those of adjacent layers. AMS 14C ages (957±43 a.d. and 578±31 a.d.) of two upper and middle turbiditic units in core C15 overlap with the historical İstanbul-Thrace (intensity=10) and İstanbul-Kocaeli (intensity=9) earthquakes of 26 October 986 and 15 August 553, respectively. This overlap, together with sedimentological characteristics, strongly suggests that the turbiditic units are related to the tectono-seismic activity of the North Anatolian Fault. The age of the lowest turbiditic unit in core C-3 was found to be 6,573±87 a b.p. (calendar) by AMS 14 C. In terms of chronostratigraphic relationships and lithological composition, the turbiditic units in core CAG-3 cannot be correlated with those in C15. This can be explained by gravity-controlled sedimentation causing wedging out of turbidites towards the edge of the basin. 相似文献