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141.
Alper Erdem Yılmaz Yeşim Dede Sağsöz Baybars Ali Fil Murat Tolga Yılmaz 《洁净——土壤、空气、水》2023,51(1):2200032
In this study, domestic wastewater was used as the electrolyte. The work was carried out with an up-flow tubular reactor, made of stainless steel that was used as cathode, while the anode electrode material was aluminum and varying values of flow regime (25, 50, 75 and 100 mL/s for continuous system), initial pH value (5, 6, 7 and 7.8) and current intensity (10, 15 and 20 A) were applied. For domestic wastewater with natural pH, the effluent pH was >9 in the batch system, while in the continuous system the pH was 8–8.5. Likewise, while the effluent temperature was up to 60°C in the batch system, it was at most 35°C in the continuous system. However, the energy consumption values in the continuous system were considerably lower compared with the batch system. At a current intensity of 10 A, 80 kWh of energy per unit volume was consumed in the batch system, while it was 50 kWh for the continuous system. The present results show that the batch system can be used for small wastewater streams whereas the continuous system can be used for large wastewater streams for domestic wastewater treatment. 相似文献
142.
Federico M. Ledesma Silvina Van der Molen Pedro J. Barón 《Journal of Sea Research》2010,63(3-4):213-216
The European green crab Carcinus maenas is a widely spread invasive species. Studying the most recently introduced population of the species in the Atlantic coast off Patagonia, it became apparent to us that carapaces (the dorsal cover of the visceral-cavity detaching from the rest of the exoskeleton after ecdysis) accumulated on the intertidal may be used as a valuable complementary material to analyze the size structure of crabs. However, since growth rate (and consequently size at instar) of crabs differs between males and females, finding a method to distinguish crab sex by observation of carapace morphology was necessary to allow the construction of independent size frequency distributions for each sex. In this work, we examined the shape of the carapaces from both sexes of C. maenas, and using Elliptical Fourier Analysis successfully identified sexual dimorphism. Thus, a reliable method to identify sexes by visual observation of the carapace was developed. Based on our results, we discuss the evolutionary significance of carapace form differentiation of both sexes. 相似文献
143.
Ziyad Matalgah H. Kırbıyık R. Civelek N. Kızıloğlu 《Astrophysics and Space Science》2007,310(3-4):189-193
V1162 is a δ-Scuti type variable star for which a rotational velocity of V
sini=46±4 km s−1 has been observed. The star has been modelled according to its observed parameters and oscillation frequencies. The results
obtained by approximating rotation to the first order have been compared with the ones provided by new calculations that include
rotation up to the second order. We found that second order rotation term should be included in frequency calculations for
comparatively high rotation speeds. 相似文献
144.
Emin Demirbağ Hülya Kurt Doğa Düşünür Kerim Sarıkavak Suna Çetin 《Marine Geophysical Researches》2007,28(4):343-353
In this study we made a comparative interpretation of multibeam bathymetric and seismic reflection data with different resolutions
and penetration properties collected in the Central Basin of the Marmara Sea. Our main objectives were (i) to investigate
and compare the active tectonic deformation observed on the sea bottom and within the uppermost sedimentary layers to that
of the deep-seated deformation within the limits of resolution and penetration of the available geophysical data and (ii)
to build a three-dimensional (3D) block diagram of the active tectonic and buried features by means of a sliced mapping technique. In this approach, we produced slice maps of the active and buried structural features at selected depths and then combined
them to form a 3D structural block diagram. Motivation for our work was to produce a 3D structural diagram to derive a more
detailed image of the structural features in the Central Basin where there is no available 3D seismic data. The observations
from the bathymetry and seismic data and developed 3D diagram support the presence of a through-going strike-slip fault that
forms a rotational depression zone against a right-stepping strike-slip faulting causing a pull-apart basin in the Central
Depression zone. 相似文献
145.
The Bekten Fault is 20-km long N55°E trending and oblique-slip fault in the dextral strike-slip fault zone. The fault is extending sub-parallel between Yenice-Gönen and Sar?köy faults, which forms the southern branch of North Anatolian Fault Zone in Southern Marmara Region. Tectonomorphological structures indicative of the recent fault displacements such as elongated ridges and offset creeks observed along the fault. In this study, we investigated palaeoseismic activities of the Bekten Fault by trenching surveys, which were carried out over a topographic saddle. The trench exposed the fault and the trench stratigraphy revealed repeated earthquake surface rupture events which resulted in displacements of late Pleistocene and Holocene deposits. According to radiocarbon ages obtained from samples taken from the event horizons in the stratigraphy, it was determined that at least three earthquakes resulting in surface rupture generated from the Bekten Fault within last ~1300 years. Based on the palaeoseismological data, the Bekten Fault displays non-characteristic earthquake behaviour and has not produced any earthquake associated with surface rupture for about the last 400 years. Additionally, the data will provide information for the role of small fault segments play except for the major structures in strike-slip fault systems. 相似文献
146.
The aim of this study was to do a preliminary assessment of the hydrochemical and microbial groundwater quality of the West
Thrace region. Forty samples of groundwater collected from Edirne (Site 1) to Gelibolu (Site 2) were assessed for their suitability
for human consumption. As3− was non-detectable in all the groundwater and Zn2+, Pb2+, F−, Cu2+, NH4+, Cn− PO43− and Cl− were all below their respective European Union drinking water directive (EU-DWD) and Turkish food codex-drinking water directive
(TFC-DWD). Maximum Acceptable Concentrations (MAC) Ni2+, Pb2+, Cd2+, Mg2+, Mn2+, and Ca2+ levels were detected in upper maximum acceptable concentrations 77.5, 42.5, 35.0, 50.0, 50.0, and 32.5% of the groundwater
samples, respectively. However, in terms of Cr3+, Ni2+ and Pb2+, the differences between groundwaters of Sites 1 and 2 were significant (p < 0.05). Eight water samples (20%) had HPC exceeding the EU and Turkish water directive limit 20 CFU (Colony Forming Unit)/ml
in drinking water and the maximum bacteria count recorded was 44 CFU/ml. Total coliforms, thermotolerant coliforms, E. coli, Enterococcus spp., Salmonella sp., Staphylococcus spp. and P. aeruginosa were detected in 25, 17.5, 15, 47.5, 15, 27.5, and 15% of the groundwater samples, respectively. Furthermore, heavy metals
and trace elements were found after chemical analyzes in most samples. The pollution of groundwater come from a variety of
sources, Meric and Ergene rivers, including land application of agricultural chemicals and organics wastes, infiltration of
irrigation water, septic tanks, and infiltration of effluent from sewage treatment plants, pits, lagoons and ponds used storage. 相似文献
147.
Removal of chromate from wastewater using amine-based-surfactant-modified clinoptilolite 总被引:1,自引:1,他引:0
P. Guzel Y. A. Aydın N. Deveci Aksoy 《International Journal of Environmental Science and Technology》2016,13(5):1277-1288
This study presents the results of chromate adsorption upon organically modified clinoptilolite obtained by the treatment of Bigadic clinoptilolite with surfactants in primary amine structure, namely 1-dodecylamine, 1-hexadecylamine and oleylamine. Natural and organo-clinoptilolites were characterized by X-ray diffraction, thermal gravimetry and Fourier transform infrared spectrometry which proved the integration of amine groups followed by the order oleylamine > 1-hexadecylamine > 1-dodecylamine. Organo-clinoptilolites were tested for their efficacy in chromate removal under base case conditions which implied 100 ppm initial concentration, pH 4.0, 10 g l?1 adsorbent dose and at 298 K. Results showed that amine loading induced chromate removal reaching up to 90 % for oleylamine-modified clinoptilolite. Experimentation was continued to determine the effects of pH, adsorbent dosage and initial concentration on chromate adsorption. Accordingly, maximum removal of 94.0 % was attained with 14 g l?1 of oleylamine-modified clinoptilolite, from Cr(VI) solution of 100 ppm initially at pH 3.0. Langmuir isotherm described the adsorption of chromate on oleylamine-modified clinoptilolite with 96.4 % consistency. Maximum theoretical uptake capacity was calculated as 6.72 mg g?1. Kinetic data were consistent with pseudo-second-order model with the controlling steps being film and pore diffusions. 相似文献
148.
149.
150.
John Douglas Sinan Akkar Gabriele Ameri Pierre-Yves Bard Dino Bindi Julian J. Bommer Sanjay Singh Bora Fabrice Cotton Boumédiène Derras Marcel Hermkes Nicolas Martin Kuehn Lucia Luzi Marco Massa Francesca Pacor Carsten Riggelsen M. Abdullah Sandıkkaya Frank Scherbaum Peter J. Stafford Paola Traversa 《Bulletin of Earthquake Engineering》2014,12(1):341-358
This article presents comparisons among the five ground-motion models described in other articles within this special issue, in terms of data selection criteria, characteristics of the models and predicted peak ground and response spectral accelerations. Comparisons are also made with predictions from the Next Generation Attenuation (NGA) models to which the models presented here have similarities (e.g. a common master database has been used) but also differences (e.g. some models in this issue are nonparametric). As a result of the differing data selection criteria and derivation techniques the predicted median ground motions show considerable differences (up to a factor of two for certain scenarios), particularly for magnitudes and distances close to or beyond the range of the available observations. The predicted influence of style-of-faulting shows much variation among models whereas site amplification factors are more similar, with peak amplification at around 1s. These differences are greater than those among predictions from the NGA models. The models for aleatory variability (sigma), however, are similar and suggest that ground-motion variability from this region is slightly higher than that predicted by the NGA models, based primarily on data from California and Taiwan. 相似文献