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The study reports the structural and spectroscopic properties of Nd3+ doped lead metatantalate phosphor series fabricated by conventional solid state method. XRD results of the PbTa2O6 phase confirm the tungsten bronze symmetry and single-phase structure between 0.5 and 10 mol% Nd3+ concentrations. The lead decrease in the structure can be associated with maintaining the charge balance and single phase due to evaporation during sintering. In SEM micrographs, the grains exhibited shapeless morphology, and the grain sizes varied from 0.5 to 7 m. In EDS results, the increase of Ta/Pb ratio in grain surfaces indicated some lead evaporation, as reported in previous studies. The absorption spectrum of PbTa2O6 host peaked around 275-280 nm, and the band gap was found to be 3.7±0.2 eV. The absorptions of Nd3+ doped phophors shifted the high wavelenght or the low band gap, where the band gaps were found between 3.1±0.2 and 3.3±0.2 eV. The PL emissions of the phosphors in near-inrared region were observed with the transitions of 4F3/2→4I9/2 (at 875 nm) and 4F3/2→4I11/2 (at 1060 nm) of Nd3+. The RL emissions or X-ray excited luminescence were monitored with the transitions of 4F3/2→4I9/2 (at 875 nm), 4F3/2→4I11/2 (at 1065 nm) in the infrared region, and the transitions of 2F(2)5/2→4F9/2, 2F(2)5/2→2H(2)11/2, 2F(2)5/2→4G5/2, 2F(2)5/2→4G7/2, 2F(2)5/2→4G9/2 in the visible region corresponding to at around 430, 455, 490, 525, and 570 nm, respectively. PL and RL emissions of the phosphors exhibited the decreasing emission intensity over 5 mol% due to the concentration quenching which may be associated with cross-relaxing mechanism. In the PL and RL spectral profiles, the similarity of splitting levels was attributed to the similarity of the local symmetry of the ligand ions surrounding the Nd3+ ion. The CIE coordinates obtained using RL emissions were found close to the blue region due to visible region transitions.

Trivalent Eu-activated MNb2O6 (M = Sr, Cd, Ni) ceramic phosphors were produced using the molten salt route, which involves a low sintering temperature and provides improved homogeneity. The photoluminescence (PL) and radioluminescence (RL) spectra of phosphors exhibited characteristic Eu3+ emissions with 5F0 → 7Fj transitions, and strong peaks occurred at the 5D0 → 7F2 transition. The PL and RL emissions of SrNb2O6:Eu3+ decreased over 3 mol%, while both emissions for CdNb2O6:Eu3+ and NiNb2O6:Eu3+ increased with increasing Eu3+ concentration. The spectral properties of phosphors were evaluated by determining Judd–Ofelt intensity parameters (Ω2, Ω4) from the PL emission spectrum. The quantum efficiencies (ηQE%) of MNb2O6:Eu3+ (M = Sr, Cd, Ni) phosphors with the highest emission were found as 61.87%, 41.89%, and 11.87% respectively. Bandwidths (σe × Δλeff) and optical gains (σe × τ) of MNb2O6:Eu3+ (M = Sr, Cd, Ni) phosphors with highest emissions were found as follows; 24.182 × 10−28, 28.674 × 10−28, 38.647 × 10−28 cm3 and 20.441 × 10−25, 13.790 × 10−25, 3.987 × 10−25 cm2 s, respectively, corresponding to the 5D0 → 7F2 transition.

In this study, in which the optical and luminescence properties of aventurine, a silicate-based mineral, were examined, the crystal structure of the mineral was examined by XRD analysis, its rheological properties and the elements it contained were determined by SEM-EDX analysis, and its structural properties were examined by FT-IR analysis. In order to determine the luminescence properties, radioluminescence (RL) and thermoluminescence (TL) methods were used and kinetic parameters were calculated. In the measurements taken in bulk and powder form of Aventurine, it was observed that the powder sample had a much better spectrum intensity, it was observed that the emission around 570 nanometers became much more pronounced in the powder sample. On the other hand, similar emissions were detected in both samples, though at different intensities. In TL analysis, it was observed that Aventurine was responsive to both X-ray and ultraviolet radiation at three different doses. While after X-ray irradiation, Aventurine exhibited TL glow curves with peaks at maximum temperatures of 90 oC and 250 oC, under UV irradiation the TL glow curves concentrated in the high-temperature region which is around 300 oC observed. Also; the TL kinetic parameters were reported; activation energy (E), the order of kinetics (b), and frequency factor (s) of the first peak have been determined in detail by using Computerized Glow Curve Deconvolution (CGCD) method.

Trivalent Dy doped TTB (tetragonal tungsten bronze) lead tantalate (PbTa2O6) phosphors were synthesized by the solid-state reaction route. Structural and spectroscopic properties have been carried out by x-ray diffraction (XRD), scanning electron microscopy–energy dispersive spectroscopy (SEM–EDS), photoluminescence (PL) and thermoluminescence (TL) analyses. XRD patterns of samples revealed the presence of TTB symmetry which continued up to 10 mol.%. SEM analysis showed the transformation of grain morphology from the shapeless-rounded to elongate. Strong PL emissions of PbTa2O6:Dy3+ phosphor were monitored at 480.5 nm and 578.5 nm. PL emission increased up to 7 mol.% and then decreased because of the concentration quenching. Decay times decreased with the increase of concentration and the end of the process (10 mol.%) fell to 355 μm. The energy transfer efficiency (ηET) energy transfer rate (W) and quantum efficiency (ηQE) of the whole process were found as 56.25%, 1.581 ms–1, and 20.27%, respectively. The CIE (Commission Internationale de l’Éclairage) coordinates of all phosphors have located close to the standard white light center, also the CIE coordinates (x, y) and CCT (correlated color temperature) value for 7 mol.% phosphor were found as (0.310, 0.295) and 6238 K, respectively. TL emissions of PbTa2O6:Dy3+ phosphor were monitored by four glow peaks in the range between 50°C and 400°C after x-ray irradiation. TL kinetic parameters were determined by the deconvolution of the 5 mol.% sample which has the highest glow curve intensity. © 2020, The Minerals, Metals & Materials Society.

In this work, Dy3+-doped SrNb2O6 phosphors were fabricated by the molten salt process, which avoids high sintering temperatures, prolonged reaction time and poor compositional homogeneity. All samples crystallized to the orthorhombic columbite structure with space group, P21/c, while a rod-like morphology was observed by scanning electron microscopy (SEM). PL (photoluminescence) and RL (radioluminescence) spectra of SrNb2O6:Dy3+ exhibited a strong blue emission peak at 576.0 nm related to 4F9/2 → 6H15/2 transition of Dy. The high RL emission of the 4F9/2 → 6H15/2 (electric dipole) transition upon X-ray-induced excitation led to a decrease in Dy3+ local environmental symmetry. The Judd–Ofelt (J–O) theory was applied to the PL excitation spectra for the calculation of optical data such as Ω2, Ω4, and Ω6 parameters, radiative transition probability (Ar), branching ratios (β, βexp) and stimulated emission cross-section (σe). The quantum efficiencies (ηQE) varied between 35.47 and 31.93%, which are compatible with theoretical quantum efficiencies based on the Einstein relation. The CIE chromaticity coordinates (x, y) and CCT (correlated color temperature) parameter for 3 mol% phosphor were defined (0.385, 0.432) and 4209 K, respectively.

TTB (tetragonal tungsten bronze) crystal structures exhibit very interesting physical properties as well as the superiority of having different cationic sites and allowing doping. In the study, the spectroscopic results of TTB-MTa2O6:Dy3+ (M = Sr, Ba, Pb) phosphors are presented using Judd-Ofelt (JO) intensity parameters. The PL and RL spectra of the phosphors exhibited the characteristic emissions of Dy in the visible and infrared regions. The PL excitation spectra were used to determine JO parameters (omega(2), omega(4), omega(6)). The decreasing trend of omega(2) parameter and PL asymmetry is SrTa2O6:Dy3+ > PbTa2O6:Dy3+ > BaTa2O6:Dy3+, which shows low electronegativity and shifting to the long wavelength of BaTa2O6:Dy3+ supports the low value of the omega(2) parameter and covalence. The PL decay profiles of all the phosphors are double exponential and the fast decreasing of PL decay components of SrTa2O6:Dy3+ is compatible with the concentration quenching after 5 mol%. The decreasing trend of the observed lifetime is in order BaTa2O6:Dy3+ > PbTa2O6:Dy3+ > SrTa2O6:Dy3+, which can be attributed to the defect centers depending on the increase of the covalency.

CdS quantum dots (QDs) which have unique luminescence efficiency were synthesized by two-phase method using oleic acid (OA) as a surfactant. The nanocomposites have been obtained by blended CdS quantum dots with low-density polyethylene (LDPE) in different ratios. Primarily, radioluminescence (RL) properties were investigated as well as their structural (FT-IR, XRD), morphological (TEM, SEM), thermal (TG-DTA) and absorption (UV–Vis) properties of these nanocomposites. The RL peaks of OA-capped CdS QD were observed at 456 nm and 655 nm. As a consequence of the nanocomposites being doped with powder CdS QD, a significant blue shift was observed in the absorption bands. The optical band gap of CdS was calculated as 2.3 eV. The nanocomposites blended with CdS QD, this value increased to 2.7 eV. It has also been observed that nanoparticles cause nanocomposites to have lower melting temperatures.

In this study Sr0.985Al2O4:0.005Eu(2+)/0.01Dy(3+) luminescent materials with long afterglow and high intensity were synthesized by flame spray pyrolysis (FSP) method for the first time. Precursor solution was divided into two separate part. One of the parts was used FSP process, the other one was dried to simulate sol- gel process. Thermal properties and organic content of FSP derived particles and dried gel were compared using DTA-TG and FTIR devices. FSP derived particles were sintered in argon medium at 1200 degrees C. Phase and elemental analysis of the final phosphors were carried out by X-Ray Diffraction (XRD) and X-Ray Photo electron Spectroscopy (XPS) measurements. Scanning electron microscopy (SEM) images were obtained to observe particle morphology. Optical properties of phosphor were determined by Photoluminescence (PL), thermoluminescence (TL) and radioluminescence (RL) measurements. The emission spectra of Sr0.985Al2O4: 0.005Eu(2+)/0.01Dy(3+) were composed by a green band at 525 nm at room temperature when it was excited by 350 nm light, assigned to anomalous luminescence originated by Eu2+ and Dy3+ in the host lattice. There were estimated peaks at around 90, 130, 170 and 200 degrees C under the main glow curve in the sample irradiated by X- ray and He- Ne laser (lambda(exc) = 632 nm). RL spectrum of Sr0.985Al2O4 : 0.005Eu(2+)/0.01Dy(3+) powders have four distinct emission peaks at around 527 nm, 576 nm, 667 nm, 753; nm and a comparatively weak emission band at about 846 nm.

Tb3+/Dy3+ co-doped CaLa2(WO4)4 (CLW: Tb3+/Dy3+) and its derivatives were synthesized by the sol-gel method. The morphology, thermal, structure and luminescent-optical properties the as-prepared light-emitting phosphors were characterized by utilizing scanning electron microscopy (SEM), differential thermal analysis (DTA)-thermogravimetric analysis (TG), X-ray diffraction (XRD) and radioluminescence (RL or X-ray luminescence) - photoluminescence (PL) –thermoluminescence (TL or TSL) - optical absorption spectrometry. The Tb3+ and Dy3+ ions were singly or doubly doped and the results were examined in detail. Moreover, for these phosphors, the energy transfer mechanisms which depend on RL and PL spectra were determined. The samples excited by X-ray demonstrate characteristic luminescence peaks of Dy3+ (422, 480, 575, 663 and 747 nm) and Tb3+ (489, 544, 586, 620, 652 and 675 nm). These emissions are similar for RL and PL measurements. It could be said that the energy transfer efficiency of the host material is perfect for rare-earth ions. The synthesized phosphors exhibit various colors from yellow to blue under UV excitation. The optical band gaps of host CLW, CLW: Tb3+, CLW: Dy3+ and co-doped CLW: Tb3+/Dy3+ were calculated at values 3.83 eV, 3.44 eV, 3.64 eV and 3.52 eV, respectively. From the results obtained, the CaLa2(WO4)4: Tb3+, Dy3+phosphors may be one of the potential candidates for light-emitting diode.

The crystal structure with different cationic sites and the superiority of allowing doping make TTB (tetragonal tungsten bronze) structures very interesting in terms of exhibiting different physical properties. The new spectroscopic and structural results of MTa2O6:Eu3+ (M = Sr, Ba, Pb) phosphors were presented in the study. The incorporation of europium activator into the different cationic (Sr, Ba, Pb) tunnel structures of TTB crystal with TaO6 octahedral exhibited interesting structural and optical properties. The relationship between coordination number and CTB showed that the highly coordinated A and B sites of TTB crystal caused the CTB to shift to low energy or over 300 nm. The spectral properties of TTB-MTa2O6 :Eu3+ (M = Sr, Ba, Pb) phosphors were compared by determining the Judd-Ofelt (JO) intensity parameters from PL emission spectrum. The (decreasing trend of the Omega(2) parameter and asymmetry ratio is SrTa2O6:Eu3+ > BaTa2O6:Eu3+ > PbTa2O6:Eu3+, and the Eu-O bonds of PbTa2O6:Eu3+ compared to other matrices indicated a more ionic character and a relatively high symmetry environment around Eu3+. The deviation of the experimental (beta(exp)) and Judd-Ofelt (beta(cal)) branching ratios for transition D-5(0)-> F-7(2) are well below 10%, indicating good consistency. All the D-5(0) decay profiles of the phosphors are exponential, and slightly reductions occurred in the luminescence lifetimes for SrTa2O6:Eu3+ and BaTa2O6:Eu3+. XRD results of Eu3+ doped SrTa2O6 series of the high-temperature TTB polymorph reported in this study confirmed the single-phase up to 10 mol%. SEM examinations revealed the change of size and shape of SrTa2O6 samples depending on Eu3+ concentration. (C) 2022 Elsevier B.V. All rights reserved.

Trivalent Eu-activated MNb

In this work, Dy3+-doped SrNb2O6 phosphors were fabricated by the molten salt process, which avoids high sintering temperatures, prolonged reaction time and poor compositional homogeneity. All samples crystallized to the orthorhombic columbite structure with space group, P21/c, while a rod-like morphology was observed by scanning electron microscopy (SEM). PL (photoluminescence) and RL (radioluminescence) spectra of SrNb2O6:Dy3+ exhibited a strong blue emission peak at 576.0 nm related to 4F9/2 → 6H15/2 transition of Dy. The high RL emission of the 4F9/2 → 6H15/2 (electric dipole) transition upon X-ray-induced excitation led to a decrease in Dy3+ local environmental symmetry. The Judd-Ofelt (J-O) theory was applied to the PL excitation spectra for the calculation of optical data such as Ω2, Ω4, and Ω6 parameters, radiative transition probability (Ar), branching ratios (β, βexp) and stimulated emission cross-section (σe). The quantum efficiencies (ηQE) varied between 35.47 and 31.93%, which are compatible with theoretical quantum efficiencies based on the Einstein relation. The CIE chromaticity coordinates (x, y) and CCT (correlated color temperature) parameter for 3 mol% phosphor were defined (0.385, 0.432) and 4209 K, respectively.

Nanotechnology has become one of the most popular areas of interdisciplinary research. In the vast majority of nanotechnology applications, polymer-based matrices were used as the dispersing medium of nanoparticles. The combination of polymer–zeolite nanocomposite has the potential to come out with the advantages of polymers and zeolites while coping with the deficiencies of both materials. In this study, the synthesis and properties of low-density polyethylene (LDPE) composites with nanozeolite + Y2O3 are investigated. Polyethylene nanocomposite fibers containing nanozeolite + Y2O3 at 5% by mass using a melt extrusion method were composed in a laboratory type twin screw extruder. The thermal properties of the composite fibers were determined by analysis of both thermal gravimetric and differential thermal spectra. Their structural properties were enlightened by scanning electron microscopy, Fourier transform infrared, and ultraviolet absorption. According to the results of X-ray diffraction tests, the samples contain crystals in semicrystalline and α form. The mechanical properties of LDPE matrices increased with the addition of nanoparticles. In addition, radioluminescence properties of the polymer were also improved after composing with nanozeolite and Y2O3.

The un-doped, Tb3+ and, Dy3+ doped LiMgPO4 phosphors were successfully synthesized by the sol-gel method. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were employed to characterize the light-emitting phosphors. The XRD spectra verify the phase formation of samples. The luminescence properties were analyzed by radioluminescence (RL), photoluminescence (PL), cathodoluminescence (CL) and, thermoluminescence (TL) spectra. Also, the effect of Tb3+, Dy3+ ions in LiMgPO4 was determined on the luminescence intensity in detail. The RL spectrum of un-doped LiMgPO4 consists of two broad emission bands in the 310–450 nm and 575–850 nm range. The maximum intensities of these bands were observed at 360 nm and 655 nm. The emission spectrum of Dy3+ doped LiMgPO4 under X-ray excitation show characteristic emissions of Dy3+ corresponds to 4F9/2→6Hj transitions. In addition to the 5D4→7Fj (j:6–1) transitions of Tb3+ doped LiMgPO4 phosphor, strong emissions derived from 5D3→7Fj (j:6–3) transitions were observed in the blue region. Also, these blue emissions were seen at RL, PL and, CL spectra. The optical absorption spectra were recorded and the energy band gaps were calculated 3.62 eV, 3.30 eV and, 4,01 eV for un-doped, Dy3+ and, Tb3+ doped LiMgPO4 phosphors, respectively. The phosphors irradiated with UV (254 nm) light. The main TL glow peak was observed at 288 °C for the Dy3+ doped phosphor, and the peaks at 198, 283 °C were observed for the Tb3+ doped phosphor. © 2020 Elsevier B.V.

For investigate spectroscopic properties, Eu3+ doped columbite type CdTa2O6 phosphors were synthesized using the solid state reaction method. The synthesized ceramic phosphors were investigated by X-ray diffraction (XRD), scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), photoluminescence (PL), radioluminescence (RL) and thermoluminescence (TL) analyses. CdTa2O6:Eu3+ phosphors exhibited emissions at 591.8 nm and 612.1 nm because of the characteristic band transitions of the Eu3+ ion. Phosphor emission increased with increasing Eu3+ ion dopant up to 1.5 mol%, and then decreased owing to concentration quenching. The decay times decreased with increasing Eu3+ dopant, while they were varied from 711 to 534 μm. The scintillation emissions of Eu3+ doped samples from the UV to near-IR spectral region were monitored by RL measurements. The high RL emission may be attributed to the good scintillation property of phosphor. TL glow curves were monitored for different Eu3+ concentrations in the range of 50 °C to 400 °C at a heating rate of 2 °C s-1, after being irradiated under short-wave UV light (254 nm). © 2018 The Royal Society of Chemistry.

Conventional narratives explain fish migrations in term of requirements (food, mates, habitats, etc.), with adequate temperatures being optional. Here, using the example of a (commercially extinct) stock of Black Sea mackerel (Scomber scombrus), we suggest that seasonal migrations are driven by seasonal temperature cycles. Therein, temperature acts as a constraint determining where the fish can be at any given time, and not a one of several factors which they would consider when choosing between alternative migration routes. Generalizing, we suggest that temperature should generally be an explicit part of hypotheses about the migratory behaviours of marine fishes. For illustration of what may occur when this is not the case, it is suggested that the non-consideration of temperature in a model of North Atlantic mackerel migration may have led, among the researchers concerned, to a sense of complacency with respect to the climate change-induced changes in the phenology of this fish in the North Atlantic, whose distribution and migration are misleadingly seen as “stochastic”., Konvencionalna literatura objašnjava migracije riba u smislu bioloških potreba (hrane; razmnožavanja; staništa; itd.) pri odgovarajućim temperaturama. U ovom radu pomoću primjera (komercijalno nestalih) zaliha crnomorske skuše (Scomber scombrus) navodimo da se sezonske migracije pokreću sezonskim temperaturnim ciklusima. Stoga; temperatura djeluje kao ograničenje određivanja gdje riba može biti u bilo kojem trenutku; a ne kao jedan od nekoliko čimbenika koje bi se razmotrili prilikom odabira između alternativnih putova migracije. Općenito; predlažemo da temperatura uglavnom bude eksplicitan dio hipoteza o migracijskom ponašanju morskih riba. Za ilustraciju onoga što se može dogoditi kada to nije slučaj; predlaže se da nerazmatranje temperature u modelu migracije sjevernoatlantske skuše; prema mišljenju znanstvenika; može dovesti do osjećaja zadovoljnosti s obzirom na promjene klime prouzročene klimatskim promjenama u fenologiji ove ribe u Sjevernom Atlantiku čija se raspodjela i migracija pogrešno smatra kao “stohastička”

In this work, highly luminescent alloyed CdSeS QDs are successfully synthesized by two phase route method by using oleic acid (OA) as a surfactant. OA capped CdSeS QDs prepared in two different synthesis duration were compared in terms of luminescence and optical properties. The nanocomposites blended with CdSeS QDs which have highly luminescent efficiency in different ratios by Low Density Polyethylene (LDPE) and these nanocomposites were mainly investigated radioluminescence (RL) and optical properties (UV/VIS absorption). Structural, morphological, thermal properties of the nanocrystal and nanocomposites were examined using; XRD, FT-IR, TEM, SEM, TG-DTA techniques. OA capped CdSeS and also nanocomposites were showed two RL spectrum peaks in green and red region at around 528 nm and 710 nm respectively. Also, it is seen that the radioluminescence intensity changes linearly with the particle size of the QDs and about 12% size change of quantum dot led to a threefold increase in RL intensity. The luminescence glow curves are in compliance with absorption and fluorescence spectra. The absorption bands showed a significant blue shift for the nanocomposites as compare to powder CdSeS. The optical band gap of the OA capped CdSeS calculated as 1.77 eV. It was observed that the optical band gap of LDPE was decreased by the adding ratio of CdSeS from 3.71 eV to 2.25 eV. © 2017 Elsevier B.V.

The ‘mean temperature of the catch’ (MTC; Cheung et al. 2013, Nature 497: 365-368.) was computed for 59 ichthyoplankton surveys conducted in several regions of the Eastern Mediterranean (off the coasts of Greece and Turkey) and in the Black and Marmara Seas. This covered 162 fish species whose preferred temperatures (PTs) were derived mainly from the data used to derive Aquamaps (see www.aquamaps.org). The (geometric mean) MTCs estimates from these 59 surveys correlated strongly with observed sea surface temperatures (SSTs), once account of the sampling regions was taken. Here, this relationship is quantified using a Type II or ‘functional’ (multiple) regression. Overall, the results suggested that the MTC could be an important descriptor of the taxonomic composition and temperature affinities of ichthyoplankton assemblages.

Tb3+/Eu3+ co-doped SrLa2(MoO4)(4) have been synthesized using the sol-gel process. The as-produced light-emitting phosphors were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), differential thermal analysis (DTA)/thermogravimetric analysis (TG), optical absorption spectra, radioluminescence (RL), and photoluminescence (PL) spectra. The effect of Tb(3+)and Eu(3+)doping concentrations on the RL and PL intensity of host material was analyzed in details. Furthermore, the energy transfer mechanism based on RL spectra were determined of Tb3+/Eu(3+)co-doped SrLa2(MoO4)(4) phosphors. When the samples excited by X-ray, the SrLa2(MoO4)(4) phosphors exhibit characteristic emissions of Tb3+ (489, 544, 586, 620 and 675 nm) and Eu(3+)d (545, 592, 614, 650 and 700 nm). Also, similar emissions are observed in the results of PL spectra, when the samples excited by 488 nm. The host material has excellent energy transfer efficiency for lanthanide ions. In addition, the luminescence spectra indicated that the energy transfer is also effective between from Tb3+ to Eu(3+)and vice versa. The CIE parameters are calculated to characterize the color emission. Under UV excitation, the synthesized materials display different color from green to red. Based on the results, the SrLa2(MoO4)(4:Eu)(3+)(3+)(,Tb) phosphors may be potential candidates for light-emitting diode. (C) 2019 Elsevier B.V. All rights reserved.

ZnO single crystals has been implanted with 400 keV Cu ions at fluences of 2,5 x 1016 ions/cm2 at room temperature. The cathodoluminescence (CL) measurements of pure and Cu implanted samples has been reported at UV-visible range at both room and different temperatures. After the implantation process, the samples were annealed for 1 hour at 1000ºC. The effects of ion implantation and annealing temperature and on the CL signals were researched with the data obtained. The CL spectrum of pure ZnO exhibited two emission bands at 385 nm and 550 nm. There are some changes in the emission bands in the CL spectrum that are thought to be due to the presence of Cu ions. Also it is possible to say that the annealing temperature can strongly influence CL intensity.

In this study, the structural and spectroscopic properties of orthorhombic PbNb2O6 doped with different concentrations of Eu3+ were studied. Interestingly, XRD analysis of undoped PbNb2O6 showed rhombohedral phase while Eu3+ doped structures exhibited an orthorhombic phase at 1250 °C. This difference was also observed in the morphology and composition of grains by SEM-EDS analysis. PL and RL emissions occurred between 550 and 850 nm owing to the 4f–4f transitions of Eu3+. The Judd-Ofelt theory was applied to the experimental data for determination of the Judd-Ofelt parameters (Ω2, Ω4), radiative transition rates (Ar) and radiative lifetimes (τr). TL glow curves were monitored by the peaks of 98 and 250 °C while emission increased up to 6 mol%. TL emission of 6 mol% phosphor depending on X-ray irradiation dose exhibited the highest intensity for 1200 Gy and appeared new peaks. Moreover, the TL emission of phosphor showed a linear relation with X-ray irradiation. The deconvolution peaks of 1200 Gy irradiated samples were determined by the CGCD method. Kinetic data of first peak (98 °C) depending on the dose increase were calculated by the PS method.

ZnO single crystals has been implanted with 400 keV Cu ions at fluences of 2,5 x 1016 ions/cm2 at room temperature. The cathodoluminescence (CL) measurements of pure and Cu implanted samples has been reported at UV-visible range at both room and different temperatures. After the implantation process, the samples were annealed for 1 hour at 1000ºC. The effects of ion implantation and annealing temperature and on the CL signals were researched with the data obtained. The CL spectrum of pure ZnO exhibited two emission bands at 385 nm and 550 nm. There are some changes in the emission bands in the CL spectrum that are thought to be due to the presence of Cu ions. Also it is possible to say that the annealing temperature can strongly influence CL intensity.

The luminescence properties of septarian have been investigated for the first time in this study, which has been the subject of many studies in both geological and geophysical fields. This sediment with a calcium carbonate structure exhibited high luminescence properties with X-ray excitation. The radioluminescence (RL) and thermoluminescence (TL) properties were investigated as well as their structural (FT-IR, XRD), morphological (SEM), thermal (TG-DTA) and absorption (UV-Vis-NIR) properties of this sediment. The broad RL peak of septarian was observed at 640 nm. There was a significant increase in the RL intensities of the sifted samples compared with the bulk sample. The TL glow curves of septarian irradiated with X-rays exhibited intense main TL glow peak having the maximum temperatures at 116 degrees C and about 390 degrees C with a heating rate of 2 degrees C/s. Also; the TL kinetic parameters were reported; activation energy (E), frequency factor (s) and the order of kinetics (b) of the first peak have been determined in detail by using peak shape (PS) and Computerized Glow Curve Deconvolution (CGCD) methods. SEM and EDS analysis were performed for the two different layers of septarian. The light colored side with the amorphous structure of the sample has more impurities (such as Fe, Al, Zr, K) than the crystallized and darker side.

Barium tantalate phosphors activated with different concentrations of Nd3+ ion were synthesized via conventional solid state reaction method. The synthesized ceramic powders were characterized by X–ray diffraction (XRD), scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), laser diode (LD) excited near infrared (NIR) photoluminescence and X-ray induced radioluminescence (RL) analyses. In XRD results, Nd3+ doped BaTa2O6 structure with tetragonal tungsten bronze (TTB) symmetry was observed to continue up to 10 mol%. In the examination of ceramic powders by SEM, grain size decreased with the increasing doping concentration. By using laser diode excited NIR photoluminescence of BaTa2O6:Nd3+ phosphor exhibited characteristic emissions at 877, 1080, and 1376 nm wavelengths due to 4F3/2 → 4I11/2, 4F3/2 → 4I11/2, and 4F3/2 → 4I11/2 band transitions respectively. Scintillation properties of Nd3+ doped samples from UV to near-IR spectral region were carried out by the radioluminescence analysis. NIR and scintillation emissions initially increased by the doping concentration, and then decreased due to concentration quenching effect. © 2018 The American Ceramic Society

In this study, CdSe quantum dots which is highly luminescent were synthesized by two phase method using oleic acid (OA) as a surfactant. New nanocomposites have been obtained by mixing CdSe quantum dots with low-density polyethylene (LDPE) in different ratios. The structural (FT-IR), morphological (TEM, SEM), thermal (TG-DTA) and absorption (UV-VIS) properties of these nanocomposites were investigated as well as their radioluminescence (RL) properties. Radioluminescence peaks at 335 nm, 510 nm and 655 nm for the oleic acid-capped CdSe nanocrystal were observed. As a consequence of the nanocomposites being doped with powder CdSe quantum dot, a significant blue shift was observed in the absorption bands. The optical band gap for CdSe was calculated as 1.82 eV. The nanocomposites blended with CdSe QD, this value increased to 3.23 eV. Bu çalışmada, yüksek parıldar madde olan CdSe kuantum noktalar, yüzey aktif madde olarak oleik asit (OA) kullanılarak çift fazlı yöntemle sentezlenmiştir., CdSe kuantum noktalarının alçak yoğunluklu polietilen (AYPE) ile farklı oranlarda karıştırılmasıyla yeni nanokompozititler elde edildi. Bu nanokompozitlerin yapısal (FT-IR), morfolojik (TEM, SEM), termal (TG-DTA) ve soğurma (UV-VIS) özelliklerinin yanı sıra radyolüminesans (RL) özellikleri araştırıldı. Oleik asit kaplı CdSe nanokristali için 335 nm, 510 nm ve 655 nm'de radyolüminesans pikleri gözlendi. Nanokompozitlerin toz haldeki CdSe kuantum nokta ile katkılandırılması sonucu, soğurma bantlarında önemli derecede mavi bölgeye kayma gözlemlendi. CdSe için optik bant aralığı 1.82 eV olarak hesaplandı. CdSe QD ile katkılandırılmış nanokompozitler için bu değer 3,23 eV'ye yükselmiştir.

The study reveals the thermoluminescence (TL) properties of white and blue chalcedony minerals which this mineral mined two different regions (Edirne and Eskişehir, respectively) of Turkey. With the help of various characterization techniques (such as X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR)), the gem-quality of the samples was tested. The TL glow curves of the samples irradiated with X-rays show intense main TL glow peak having the maximum temperatures at 100 °C and 121 °C with a heating rate of 2 °C/s, respectively. The TL kinetic parameters of the samples are reported here for the first time. Activation energy (E), frequency factor (s) and the order of kinetics (b) of these peaks have been determined in detail by using various heating rates (VHR) and peak shape (PS) methods and verified by Computerized Glow Curve Deconvolution (CGCD). The CGCD method was used to determine the number of peaks associated with the TL glow curves. The values of E calculated with these three methods are a good agreement. © 2018 Elsevier Ltd

This study aims to find out usage of zinc oxide (ZnO) and 2-hydroxy-4-methoxybenzophenone (BP-3) for getting better optical and structural properties of nanocomposites. Polymer nanocomposites were prepared by adding zinc oxide for minimizing UV rays effects of the sun with the particle size of nanometer in different ratios to a low density polyethylene (LDPE). The polymer mixtures were synthesized by mixing nanocomposite samples with BP-3 featuring UV stabilizer. Besides making tensile testing measurements, in order to find out the optical, structural, mechanical and thermal changes, the new polymer nanocomposites were characterized by XRD, TG-DTA spectra, and SEM images. The samples with zinc oxide which show luminescent properties were examined in terms of radioluminescence features. Radioluminescence spectrum showed characteristic peaks of zinc oxide dispersed nanocomposites prepared with LDPE. The intensity of the characteristic peaks at 530 and 390 nm (exciton) increased by increasing rates of nanopowder zinc oxide while adding BP-3 to the composites caused a decrease in intensity of radioluminescence. © 2018, Pleiades Publishing, Ltd.

Bu çalışmada, yüksek parıldarmadde olan CdSe kuantum noktalar, yüzey aktif madde olarak oleik asit (OA)kullanılarak çift fazlı yöntemle sentezlenmiştir., CdSe kuantum noktalarınınalçak yoğunluklu polietilen (AYPE) ile farklı oranlarda karıştırılmasıyla yeninanokompozititler elde edildi. Bu nanokompozitlerin yapısal (FT-IR), morfolojik(TEM, SEM), termal (TG-DTA) ve soğurma (UV-VIS) özelliklerinin yanı sıraradyolüminesans (RL) özellikleri araştırıldı. Oleik asit kaplı CdSenanokristali için 335 nm, 510 nm ve 655 nm'de radyolüminesans pikleri gözlendi.Nanokompozitlerin toz haldeki CdSe kuantum nokta ile katkılandırılması sonucu,soğurma bantlarında önemli derecede mavi bölgeye kayma gözlemlendi. CdSe içinoptik bant aralığı 1.82 eV olarak hesaplandı. CdSe QD ile katkılandırılmış nanokompozitleriçin bu değer 3,23 eV'ye yükselmiştir., In this study, CdSe quantum dots which is highly luminescent weresynthesized by two phase method using oleic acid (OA) as a surfactant. Newnanocomposites have been obtained by mixing CdSe quantum dots with low-densitypolyethylene (LDPE) in different ratios. The structural (FT-IR), morphological(TEM, SEM), thermal (TG-DTA) and absorption (UV-VIS) properties of thesenanocomposites were investigated as well as their radioluminescence (RL) properties.Radioluminescence peaks at 335 nm, 510 nm and 655 nm for the oleic acid-cappedCdSe nanocrystal were observed. As a consequence of the nanocomposites beingdoped with powder CdSe quantum dot, a significant blue shift was observed inthe absorption bands. The optical band gap for CdSe was calculated as 1.82 eV.The nanocomposites blended with CdSe QD, this value increased to 3.23 eV.

Europe has a long tradition of exploiting marine fishes and is promoting marine economic activity through its Blue Growth strategy. This increase in anthropogenic pressure, along with climate change, threatens the biodiversity of fishes and food security. Here, we examine the conservation status of 1,020 species of European marine fishes and identify factors that contribute to their extinction risk. Large fish species (greater than 1.5 m total length) are most at risk; half of these are threatened with extinction, predominantly sharks, rays and sturgeons. This analysis was based on the latest International Union for Conservation of Nature (IUCN) European regional Red List of marine fishes, which was coherent with assessments of the status of fish stocks carried out independently by fisheries management agencies: no species classified by IUCN as threatened were considered sustainable by these agencies. A remarkable geographic divergence in stock status was also evident: in northern Europe, most stocks were not overfished, whereas in the Mediterranean Sea, almost all stocks were overfished. As Europe proceeds with its sustainable Blue Growth agenda, two main issues stand out as needing priority actions in relation to its marine fishes: the conservation of marine fish megafauna and the sustainability of Mediterranean fish stocks. Marine fishes exhibit high biodiversity 1,2 and have been culturally and nutritionally important throughout human history 3 . Europe, in particular, has a well-documented history of exploiting marine fish populations, written records of which commence in the classical works of ancient Greece. Although this historical exploitation has undoubtedly altered populations 4,5 and changed many seascapes 6 , marine defaunation in the region has not been as great as in terrestrial systems 7 . However, the use of ocean space and resources is increasing due to Europe’s Blue Growth strategy 8 , the nutritional requirements of an expanding human population are growing 9,10 and marine ecosystems will experience unusually rapid changes in future due to climate change 11,12 . Consequently there are imminent threats both to European marine biodiversity and fish resources 13 . It is important, therefore, to assess the threats of extinction to fish species and to ensure consistency in the management approach by the various agencies involved. We analysed data on the conservation status of 1,020 species of Europe’s marine fishes from the recent International Union for Conservation of Nature (IUCN) Red List assessments 14 to identify characteristics that make Europe’s fishes most susceptible to extinction risk. We then compared the Red List with 115 fish stock assessments (of 31 species) made by intergovernmental agencies charged with providing advice on the exploitation of commercial fishes. Previous comparisons of this sort applied criteria under various modelling assumptions 15,16, 17 or limited the comparison to biomass reference points 18 .

The calculation of the kinetic parameters of a thermoluminescence material (kinetic order (b), activation energy (E) and frequency factor (s)) by using the thermoluminescence (TL) method is extremely important in determining the kinetic characterization of the materials. Sodium Chloride (NaCl) is an inorganic salt. It is a crystal well known for its luminescent properties, with a simple cubic structure and its band gap is rather large (~ 8.5 eV). In this work, it was reported the TL response of the material in the range of 50– 400 oC and calculated kinetic parameters of sea salt. Two glow peaks were observed at 100 oC and 235 oC in the TL glow curve of sea salt with a heating rate 2 oC/s after X-ray irradiation. The Tm-Tstop method was used to determine the overlapping peaks under the main peak at 100 oC. With the computerized glow curve deconvolution (CGCD) method, the peak analysis was performed. In addition, kinetic parameters were calculated using various heating rates and peak shape. The b = 1.5, E = 0.88 eV and s = 1.7x1011 s-1 values were calculated using the peak shape method The calculation of the kinetic parameters of a thermoluminescence material (kinetic order (b), activation energy (E) and frequency factor (s)) by using the thermoluminescence (TL) method is extremely important in determining the kinetic characterization of the materials. Sodium Chloride (NaCl) is an inorganic salt. It is a crystal well known for its luminescent properties, with a simple cubic structure and its band gap is rather large (~ 8.5 eV). In this work, it was reported the TL response of the material in the range of 50– 400 oC and calculated kinetic parameters of sea salt. Two glow peaks were observed at 100 oC and 235 oC in the TL glow curve of sea salt with a heating rate 2 oC/s after X-ray irradiation. The Tm-Tstop method was used to determine the overlapping peaks under the main peak at 100 oC. With the computerized glow curve deconvolution (CGCD) method, the peak analysis was performed. In addition, kinetic parameters were calculated using various heating rates and peak shape. The b = 1.5, E = 0.88 eV and s = 1.7x1011 s-1 values were calculated using the peak shape method

Nature Ecology & Evolution 1, 0170 (2017); published 26 May 2017; corrected 12 June 2017. In the original version of this Article, the European Commission was mistakenly included as an affiliation for Christos D. Maravelias. His contribution to this work was exclusively completed while at the Hellenic Centre for Marine Research.

The aim of this study is to reconstruct the total historic catch of Bulgarian marine fisheries in their Exclusive Economic Zone for the time period 1950-2013, including unreported landings, discards, recreational and subsistence catches from the ecosystem. The landings data officially reported by Bulgaria to the Food and Agriculture Organization of the United Nations for the Mediterranean and Black Seas (FAO Area 37) were revised in line with all available information. The reconstructed total catch for 1950-2013 was 1.7 times the (adjusted) baseline data reported by Bulgaria to FAO and 1.5 times the unadjusted data as reported by FAO. This study revealed major deficiencies which exist in the officially reported Bulgarian catch data, foremost being the large amount of unreported industrial catches, especially for the last two decades. Furthermore, the exclusion of some fisheries sectors, notably the absence of data on the subsistence and recreational fisheries in reported data are also noteworthy.

This short-term study on commercial discards was carried out in fishing grounds around Gökçeada Island in the northeastern Aegean Sea, a geographic area where fisheries information is rather limited. A total of 28 bottom trawls were performed between 70 and 410 m depth from December 2009 to February 2010. All the samples were collected on board a commercial trawler under commercial fishing conditions. A total of 3143 kg of biomass was caught in 28 valid hauls. Landings accounted for about 67% of the total catch while the remaining 33% was discarded. Fish species comprised 85% of the total catch and their composition could be divided into four main groups related to depth: shallow shelf (70 to 88 m), deep shelf (155 to 180 m), shelf break (196 to 276 m), and upper slope (307 to 410 m). Fish dominated the abundance and biomass of both landings and discards in all bathymetric strata. Echinoderms also accounted for a large proportion of the discards. Mean total catches varied between 78.4 kg/h on the shallow shelf and 38.1 kg/h on the shelf break with no differences in the landing biomass between groups, but with slightly higher discards over the shallow shelf. Taking into account the preliminary nature of the findings, based on a short-term analysis, the minimum mesh size and minimum landing size currently applied in the Turkish bottom trawl fishery are not sufficient to reduce discards and to protect juveniles of commercially important species in the northeastern Aegean Sea. Este estudio a corto plazo sobre los descartes de la flota comercial de arrastre se llevó a cabo en las zonas de pesca alrededor de la isla Gökçeada en el noreste del mar Egeo, una zona geográfica en la que la información sobre las pesquerías es bastante limitada. Se realizaron un total de 28 pescas de arrastre de fondo entre 70 y 410 m de profundidad de diciembre 2009 a febrero de 2010. Todas las muestras se recogieron a bordo de un embarcación de pesca de arrastre siguiendo las mismas condiciones de pesca comercial. Se capturaron un total de 3143 kg de biomasa en 28 lances válidos. Los desembarques comerciales representaron alrededor del 67% de la captura total, mientras que el resto (33%) se descartó. El 85% de la captura total estuvo compuesta por especies de peces. La composición específica se pudo separar en cuatro grupos principales relacionados con la profundidad : la plataforma poco profunda (70 a 88 m), la plataforma profunda (155-180 m), el borde inferior de la plataforma (196 a 276 m) y el talud superior (307-410 m). Los peces dominaron la abundancia y biomasa tanto de los desembarques comerciales como de los descartes en todos los estratos batimétricos. Además los equinodermos también fueron un grupo importante de los descartes. La media de las capturas totales varió entre 78.4 kg/h en la plataforma poco profunda y 38.1 kg/h en el borde de la plataforma, sin diferencias en la biomasa desembarcada entre los dos grupos, pero siendo los descartes ligeramente superiores en la plataforma poco profunda. Teniendo en cuenta el carácter preliminar de los resultados, obtenidos sobre la base de un análisis a corto plazo, el tamaño mínimo de malla de la red y la talla mínima de las especies comerciales aplicada hoy en día en la pesquería de arrastre de fondo de Turquía no son suficientes para reducir los descartes y proteger a los juveniles de las especies de importancia comercial en el Mar Egeo nororiental.

Bu calismada, Ege Universitesi Dis Hekimligi Fakultesi’nden alinan saglikli dis minelerinin termoluminesans (TL) ozellikleri incelenmistir. Dis minesi X isinlari ile uyarilarak farkli isitma hizlarinda (β) (210oC/s) TL spektrumlari alinmistir. 50-400 oC araliginda dis minesi icin yaklasik 210 oC’ de genis bir TL piki oldugu gozlenmistir. 210 oC’ deki pikin isitma hizi ve X isini dozuna bagliligi (doz yanit) incelenmis, ayni zamanda pik sekli ve isitma hizi metodlari kullanilarak dis minesi icin kinetik parametreler hesaplanmistir

Spodumen X-isini, beta ve gama isinlari icin yuksek termoluminesans cevabi veren bir aluminasilikattir. Kimyasal bilesiminden dolayi (LiAlSi 2 O 6 ) notron dozimetri olarak kullanilmaktadir. Bu calismada Afganistan’ dan cikarilan pembe spodumenin optik sogurma ve termoluminesans ozellikleri incelenmistir. Alinan olcumlerde spodumenin yaklasik 301 o C de bir ana termoluminesans (TL) piki gorulmustur. Kinetik parametreleri dort farkli yontemle ( Pik sekli metodu, Farkli isitma hizlari metodu, Baslangic artis metodu ve bilgisayarli isima egrisi cozumleme metodu “CGDC”) hesaplanmistir. XRD ve element analiz sonuclari ornek icerisinde Fe ve Mn basta olmak uzere cesitli safsizliklarin oldugunu gostermistir.

International audience; Understanding the distribution of genetic diversity in the light of past demographic events linked with climatic shifts will help to forecast evolutionary trajectories of ecosystems within the current context of climate change. In this study, mitochondrial sequences and microsatellite loci were analysed using traditional population genetic approaches together with Bayesian dating and the more recent approximate Bayesian computation scenario testing. The genetic structure and demographic history of a commercial fish, the black scorpionfish, Scorpaena porcus, was investigated throughout the Mediterranean and Black Seas. The results suggest that the species recently underwent population expansions, in both seas, likely concomitant with the warming period following the Last Glacial Maximum, 20 000 years ago. A weak contemporaneous genetic differentiation was identified between the Black Sea and the Mediterranean Sea. However, the genetic diversity was similar for populations of the two seas, suggesting a high number of colonizers entered the Black Sea during the interglacial period and/or the presence of a refugial population in the Black Sea during the glacial period. Finally, within seas, an east/west genetic differentiation in the Adriatic seems to prevail, whereas the Black Sea does not show any structured spatial genetic pattern of its population. Overall, these results suggest that the Black Sea is not that isolated from the Mediterranean, and both seas revealed similar evolutionary patterns related to climate change and changes in sea level.

Natural blue-green beryl from Turkey has been investigated using scanning electron microscopy-energy-dispersive spectroscopy (SEM-EDS), X-ray diffraction (XRD) and Cathodoluminescence (CL). Beryl has the chemical formula Be 3 Al 2 Si 6 O 18 and is hexagonal with space group P 6/ mcc . Chemical analyses of the beryl sample utilised inductively coupled plasma-atomic emission spectroscopy (ICP-AES) for major oxides and trace elements. It shows that the beryl sample is rich in Cs (531 ppm) and contains low concentrations of transition-metal ions, in total 2.29 wt.% Fe, 269 ppm Mn, V

The mean trophic level, i.e., the Mean Trophic Index (MTI) and Mean Temperature of the Catch (MTC) were estimated for Turkish waters in the Eastern Mediterranean and the Black Sea based on the reconstructed marine fisheries catches (consisting of N = 88 species and/or higher taxa) of in Turkish waters for the year 1950 to 2010. The MTI decreased in both regions of Turkey, following expectations, but the MTC showed different trends in these two regions. It increased (by 0.48 °C·decade-1), along with the SST in the Eastern Mediterranean, while it fluctuated in the Black Sea. This fluctuating behaviour, however, was similar to the fluctuating tendency of SST in the Black Sea. This suggests that the MTI and MTC can be relied upon as indicators of fisheries impacts on ecosystems, and of the impact of changing temperatures on fisheries, respectively.

The Turkish anchovy catch in the Georgian waters between 2003 and 2009 was estimated as 60,968 tons. Total quota for pelagic fish was declared as 60,000 tons by the Georgian authorities in 2007. Although the anchovy fishing in the Georgian Black Sea by the Turkish fleet started in 1996, there is no information on anchovy fisheries which were made according to the bilateral agreement between Turkish and Georgian companies. In the Black Sea, there are several shared stocks occurring within the exclusive economic zones of the two or more coastal states. These resources need to be sustainable, managed by riparian countries with regional cooperation. An urgent anchovy stock assessment study is needed in order to manage Georgian fisheries in a sustainable manner. It is recommended that fishing in the Abkhazia region also needs to be managed in order to respect sovereignty of the coastal states and international law.

Crise, A. ... et. al.-- 12 pages, 1 figure, 5 tables, PERSEUS project aims to identify the most relevant pressures exerted on the ecosystems of the Southern European Seas (SES), highlighting knowledge and data gaps that endanger the achievement of SES Good Environmental Status (GES) as mandated by the Marine Strategy Framework Directive (MSFD). A complementary approach has been adopted, by a meta-analysis of existing literature on pressure/impact/knowledge gaps summarized in tables related to the MSFD descriptors, discriminating open waters from coastal areas. A comparative assessment of the Initial Assessments (IAs) for five SES countries has been also independently performed. The comparison between meta-analysis results and IAs shows similarities for coastal areas only. Major knowledge gaps have been detected for the biodiversity, marine food web, marine litter and underwater noise descriptors. The meta-analysis also allowed the identification of additional research themes targeting research topics that are requested to the achievement of GES. © 2015 The Authors, This work has been partially funded by the EC FP7 PERSEUS Project (Grant. Agr. 287600)

The Turkish Island of Gokceada is located in the northeastern Aegean Sea. In this preliminary study, six collecting stations, at depths 5–15 were sampled. A total of 76 species were collected by trammel and gill nets (59 species) or by trawls (17 species). At each station and during each season the Shannon‐Weaver Diversity index and Simpson Dominance index were calculated. These indices were compared with their mean values for each station. The similarity among the stations was estimated Sorenson's (1948) formula. Similarity index, stations I and III showed the highest similarity (80%), and stations IV‐VI (44%) and V‐VI (45%) showed the lowest similarity.

Two marine areas (the northern Aegean Sea and southern part of the Sea of Marmara, Turkey) which have different trophic and hydrodynamic characteristics were compared regarding diversities of bacteria, phytoplankton, zooplankton, benthos, fish and cetaceans. During the study period (2006–2007), a total of 27 taxa of aerobic heterotrophic mesophilic bacteria including ten bacterial classes were reported for the first time from both seas. A total of 103 taxa from seven algal classes were determined. Copepod species in the northern Aegean Sea and southern part of the Sea of Marmara were recorded as 44 and 27, respectively. A total of 523 underwater photographs were taken at ten stations and the benthic organism diversity were examined for the first time using the photo-quadrat technique. A total of 72 fish belonging to 36 families, were determined. During the study, a total of 1548 nautical miles of survey effort were conducted for cetacean observation. Living individuals of the Stenella coeruleoalba (striped dolphin) were recorded for the first time. This study is intended to be the first detailed description of the diversity of bacteria, phytoplankton, zooplankton, benthos, fish and cetaceans and comparison of two different marine environments in order to put forth the situation of the ecosystem as it is today.

The demersal fish assemblages of the south-western Sea of Marmara and the north-eastern Aegean Sea were examined in relation to their biogeographical and environmental conditions. Sampling was carried out during bottom trawl surveys conducted during five periods between June 2006 and August 2007. A total of 40 hauls were processed, including 16 in the Sea of Marmara (38–74 m deep) and 24 in the north-eastern Aegean Sea (63–401 m deep). A total of 47,940 individuals, from 91 species and 47 families were collected. Cluster analysis of catch data indicated that there were three assemblages, one in the shelf of the Sea of Marmara and two in the Aegean Sea (200 m depth). The numerical abundance and biomass of fish, mean fish weight, mean species richness, diversity and evenness were compared between these assemblages. Multivariate analysis was used to test differences in environmental conditions between areas, and relationships between species and environmental variables were explored by using redundancy analysis. In addition to bathymetric differences, differences in both diversity and species composition were observed between shelf assemblages in the two nearby areas. The distinct biogeographical, environmental characteristics (depth, dissolved oxygen and temperature) and fishing pressure are discussed as the main factors which could explain the differences detected., Sí

In this study, the presence and description of Scorpaena loppei in the Turkish seas is reported. Two specimens were caught in Mersin-Tasucu Bay on 24 August 2006 by trawl net. The first specimen was 42.8 mm standard length, and the second specimen was 52.3 mm.