Strategies for Successful ANAMMOX Enrichment at Laboratory Scale     

Sinan Uyanik  Ozan K. Bekmezci  Adem Yurtsever 《洁净——土壤、空气、水》2011,39(7):653-657

Studies on anaerobic ammonium oxidation (ANAMMOX) have been increasing due to its advantages over traditional nitrification–denitrification systems. However, long and difficult start‐up periods of ANAMMOX reactors may sometimes be frustrating for researchers dealing with them first time in the lab. Therefore, a guide for starting up ANAMMOX reactors will greatly help them and enhance the use of this technology. Three trials, each has three reactors, have been carried out to reach successful start up in this study. An expected ANAMMOX enrichment could not be achieved in the first and second trials. Under the light of the experiences gained from the unsuccessful ones, the third trial resulted in >95% ammonium removals within 20–50 days. It is possible to startup or to enrich ANAMMOX reactors within 50 days by presented strategy guide.  相似文献   

On‐line Solid Phase Extraction of Copper in Water Samples with Flow Injection Flame Atomic Absorption Spectrometry     

Tülin Çetin  Ahmet Ülgen  Şerife Tokalıoğlu 《洁净——土壤、空气、水》2011,39(3):244-249

An on‐line solid phase extraction method for the preconcentration and determination of Cu(II) by flame atomic absorption spectrometry has been described. The procedure is based on the retention of Cu(II) ions at pH 6.0 on a minicolumn packed with Amberlite XAD‐1180 resin impregnated with chrome azurol S. After preconcentration, Cu(II) ions adsorbed on the impregnated resin were eluted by 1 mol L^?1 HNO₃ solution. Several parameters, such as pH, type of eluent, flow rates of sample and eluent solutions, amount of resin were evaluated. At optimized conditions, for 3.5 min of preconcentration time, the system achieved a detection limit of 1.0 µg L^?1, and a relative standard deviation of 1.2% at 0.2 µg mL^?1 copper. An enrichment factor of 56‐fold was obtained with respect to the copper determination. The proposed method was successfully validated by the analysis of standard reference material (TMDA 54.4 lake water) and recovery studies. The method was applied to the preconcentration of Cu(II) in natural water samples.  相似文献   

On the <Emphasis Type="Italic">P</Emphasis> and <Emphasis Type="Italic">S</Emphasis> Receiver Functions Used for Inverting the One-Dimensional Upper Mantle Shear-Wave Velocities     

Özcan Çakır  Murat Erduran 《Surveys in Geophysics》2011,32(1):71-98

The teleseismic P receiver functions are customarily inverted to attain the seismic velocities beneath a seismic station. Surface wave dispersion data are often added to reduce the effect of the non-uniqueness. The combination of P receiver function and surface wave works well in resolving the structures in the crust and uppermost mantle, but is less effective in characterizing greater (lithosphere and asthenosphere) depths due to the interference from crustal multiples. A solution to this problem is jointly to model teleseismic S receiver functions with surface wave and P receiver functions. This study adopts a fast, one-dimensional (1-D) inversion scheme. To avoid the effect of multidimensional structures away from the seismic station, we eliminate multiples that reverberate between the surface and interfaces below a restriction depth (RD), as well as S-to-P conversions below an inversion depth (ID). P-to-S conversions off the interfaces above the half-space and S-to-P conversions above the ID and multiples above the RD are properly modelled. This approach favours ray paths travelling close to stations and is, therefore, more suitable for 1-D inversions. We perform numerical experiments with and without noise and highlight the advantages of a joint receiver function and surface wave analysis.  相似文献   

An integrated earthquake vulnerability assessment framework for urban areas   总被引：1，自引：1，他引：0  

H. S. B. Duzgun  M. S. Yucemen  H. S. Kalaycioglu  K. Celik  S. Kemec  K. Ertugay  A. Deniz 《Natural Hazards》2011,59(2):917-947

In this paper, an integrated urban earthquake vulnerability assessment framework, which considers vulnerability of urban environment in a holistic manner and performs the vulnerability assessment for the neighborhood scale, is proposed. The main motivation behind this approach is the inability to implement existing vulnerability assessment methodologies for countries like Turkey, where the required data are usually missing or inadequate for the decision-makers in prioritization their limited resources for risk reduction in the administrative units from which they are responsible for. The methodology integrates socio-economical, structural, coastal, ground condition, vulnerabilities (fragilities), as well as accessibility to critical services. The proposed methodology is implemented for Eskisehir, which is one of the metropolitans of Turkey. In the implementation of the proposed framework, geographic information system (GIS) is used. While the overall vulnerabilities obtained for neighborhoods are mapped in GIS, the overall vulnerabilities obtained for buildings are visualized in 3D city model. The main reason behind using different mapping and visualization tools for vulnerabilities is to provide better ways for communicating with decision-makers. The implementation of the proposed vulnerability assessment methodology indicates that an urban area may have different vulnerability patterns in terms of structural, socio-economical, and accessibility to critical services. When such patterns are investigated, effective vulnerability reduction policies can be designed by the decision-makers. The proposed methodology well serves for this purpose.  相似文献   

Investigation of water quality on Gökçekaya dam lake using multivariate statistical analysis,in Eskişehir,Turkey   总被引：1，自引：0，他引：1  

B. S. Akin  T. Atıcı  H. Katircioglu  F. Keskin 《Environmental Earth Sciences》2011,63(6):1251-1261

Gökçekaya Dam is one of the dams located on the Sakarya River (Eski?ehir) in Turkey and is approximately 38 years old. No study regarding to the water quality of the dam lake has been hitherto made. This study aimed at determining the seasonal variations with physical, chemical, and biological parameters of the water quality of the dam lake. Depth-wise water samples were taken from five selected stations, in seasonal periods during 2005–2008, and anlayzed. The quality of water was classified in accordance with the results and taking into consideration many parameters. At the same time, number and type diversities of dissolved heavy metals and algae population were analyzed. Using principal component analysis (PCA) and classification analysis (CA) methods, differences between these parameters and samples from stations have been determined . The analysis showed that Gökçekaya dam lake, formerly an oligotrophic lake, has become a mesotrophic lake. And according to the results thereof the Lake has mezotrophic characteristics due to the sudden changes (including household waste water inflow and opening the Sar?yar dam lake shutters) in certain periods and in some stations. Hierarchical clustering analysis, revealed no significant difference between the measured parameters. And according to the Water Pollution Control Regulations in Turkey (WPCR) Gökçekaya dam lake is in the first class quality in terms of anions, cations, heavy metals, temperature, and pH values. However, the is of first class quality presence of nitrite reduces the water quality in the lake and causes this lake to be classified in the fourth class quality.  相似文献   

Assessment of potential seismic hazard and site effect in Antakya (Hatay Province), SE Turkey     

Semir Över  Aydın Büyüksaraç  Özcan Bekta  Ahmet Filazi 《Environmental Earth Sciences》2011,62(2):313-326

Antakya city is at risk because of strong earthquakes occurring in the area, and different soil conditions that can produce variation of the ground motion amplification. Microzonation of cities provides a basis for site-specific hazard analysis in urban settlements. In particular, seismic microzonation can be provided by means of detailed seismic assessment of the area, including earthquake recordings and geological studies. In this paper, we propose a preliminary microzonation map for the city of Antakya, based on the variation of the dominant periods and shear velocities of the sediments covering the area. The periods are retrieved from microtremor measurements conducted at 69 sites, using the horizontal-to-vertical spectral ratio technique. The results of microtremor analysis were compared with data obtained from refraction microtremor (ReMi) measurements at four profiles crossing the studied area. According to the classification of dominant periods, Antakya city can be divided into five zones, probably prone to different levels of seismic hazard. The shorter natural periods are in inner Antakya and both the sides of Asi River (i.e., northern and southern parts). The eastern and western parts of Antakya have maximum dominant periods. The V _s ³⁰ values were calculated by using the ReMi method along the profiles. Antakya city has V _s ³⁰ values in the range of category C of the national earthquake hazard reduction programme site classification.  相似文献   

Atmospheric and adaptive optics     

Paul?HicksonEmail author 《Astronomy and Astrophysics Review》2014,22(1):76

Atmospheric optics is the study of optical effects induced by the atmosphere on light propagating from distant sources. Of particular concern to astronomers is atmospheric turbulence, which limits the performance of ground-based telescopes. The past two decades have seen remarkable growth in the capabilities and performance of adaptive optics (AO) systems. These opto-mechanical systems actively compensate for the blurring effect of the Earth’s turbulent atmosphere. By sensing, and correcting, wavefront distortion introduced by atmospheric index-of-refraction variations, AO systems can produce images with resolution approaching the diffraction limit of the telescope at near-infrared wavelengths. This review highlights the physical processes and fundamental relations of atmospheric optics that are most relevant to astronomy, and discusses the techniques used to characterize atmospheric turbulence. The fundamentals of AO are then introduced and the many types of advanced AO systems that have been developed are described. The principles of each are outlined, and the performance and limitations are examined. Aspects of photometric and astrometric measurements of AO-corrected images are considered. The paper concludes with a discussion of some of the challenges related to current and future AO systems, particularly those that will equip the next generation of large, ground-based optical and infrared telescopes.  相似文献   

Mantle lithosphere,asthenosphere and transition zone beneath Eastern Anatolia     

Erduran  M.  Oreshin  S.  Vinnik  L.  Çakır  Ö.  Makeyeva  L. 《Journal of Seismology》2022,26(2):265-281

Journal of Seismology - By using P and S wave receiver functions and P and S wave travel time residuals, we have found velocity models for 16 seismograph stations in Eastern Anatolia. Our study is...  相似文献   

Effect of particle characteristics on the evolution of particle size,particle morphology,and fabric of sands loaded under uniaxial compression     

Ganju  Eshan  Kılıç  Mustafa  Prezzi  Monica  Salgado  Rodrigo  Parab  Niranjan  Chen  Wayne 《Acta Geotechnica》2021,16(11):3489-3516

Acta Geotechnica - This paper presents the results and analyses of uniaxial compression experiments performed on three silica sands. The sands have comparable particle-size distributions, but their...  相似文献   

Strange quark matter solutions for Marder’s universe in f(R,T) gravity with Λ     

S. Aygün  C. Aktaṣ  İ. Yılmaz 《Astrophysics and Space Science》2016,361(12):380

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