Evaluation of trace element contents of some herbal plants and spices retailed in Kayseri,Turkey

The trace element contents of seven kinds of herbal plants and spice samples retailed in local markets in Kayseri-Turkey were determined by flame atomic absorption spectrometry after digestion with HNO₃/H₂O₂ mixture. The concentration ranges for the studied elements were found as 6.0–15.2, 0–32.2, 80.0–324.8, 8.1–386.3, and 13.1–36.2 μg/g for copper, nickel, iron, manganese, and zinc, respectively. The levels of cobalt, lead, and chromium ions in all the investigated samples were found to be below the detection limit of flame atomic absorption spectrometry. The results found in the present work were compared with values in the literature.     

Heavy metal contents of refined and unrefined table salts from Turkey, Egypt and Greece

Trace metal contents of 28 of refined and unrefined table salt samples from Turkey, Egypt and Greece have been determined by flame atomic absorption spectrometry after coprecipitation by dysprosium(III) hydroxide. Copper, nickel, cobalt, manganese, lead and cadmium levels were found in the range of 0.17-0.47, 0.16-1.57, 0.22-0.48, 0.26-4.68, 0.50-1.64 and 0.14-0.30 microg g(-1), respectively. The results found in the presented work were compared with literature values.     

Trace element content in marine algae species from the Black Sea, Turkey

Trace element content of marine algae species collected from the Black Sea coasts were determined by atomic absorption spectroscopy after microwave digestion. Trace element content in marine algae species were 1.70-17.1 microg/g for copper, 3.64-64.8 microg/g for zinc, 9.98-285 microg/g for manganese, 99-3,949 microg/g for iron, 0.50-11.6 microg/g for chromium, 0.27-36.2 microg/g for nickel, 11-694 microg/kg for selenium, 0.50-44.6 microg/kg for cadmium, 1.54-3,969 microg/kg for lead, 1.56-81.9 microg/kg for cobalt. While iron was the highest trace element concentration, cadmium was the lowest in samples. Most of the analyzed samples were edible. The samples are consumed for human diet in several countries.     

Spatial variability of depth and salinity of groundwater under irrigated ustifluvents in the Middle Black Sea Region of Turkey

Information on the potential risk for soil salinity buildup can be very helpful for soil salinity management in irrigated areas. We evaluated the spatial and temporal variability of groundwater salinity (GWS) and groundwater depth (GWD), which are two of the most important indicators of soil salinity, by indicator kriging technique in a large irrigated area in northern Turkey. GWS and GWD were measured on a monthly basis from irrigation season (August 2003) to rainy season (April 2004) at 60 observation wells in the 8,187-ha irrigated area. Five indicator thresholds were used for GWS and GWD. The semivariogram for each of the thresholds for both variables was analyzed then used together with experimental data to interpolate and map the corresponding conditional cumulative distribution functions (CCDF). Risk for soil salinity buildup was greater in the irrigation season compared to that in the rainy season. The greatest risk for soil salinity buildup occurred in the eastern part of the study area, suffering from poor drainage problem due to malfunctioning drainage infrastructure, as indicated by the CCDF of GWS and GWD obtained in both seasons. It was concluded that a combination of mechanical and cultural measures should be taken in high-risk locations to avoid further salinity problems.     

Mineral contents of the head, caudal, central fleshy part, and spinal columns of some fishes

In the experiment, mineral contents of the head, caudal, central fleshy part, and spinal columns of fishes were determined by inductively coupled plasma atomic emission spectrometry. The Ca content of base fleshy part ranged from 1,682 to 5,505 mg/kg. The Ca contents of central fleshy part were found between 104 and 428 mg/kg. This value was found between 5,582 and 7,368 in the spinal column parts. The K content in general ranged from 2,411 (Carassius gibellio) and 4,419 mg/kg (Scomber scombrus). The highest potassium was found on the central fleshy part and ranged between 3,214 and 4,419. The P content was found mostly on the bones and it range between 28,833 and 34,726. The least phosphor amount was found on the central fleshy part. While the Cd content ranges between 0.019 ppm and 0.104 mg/kg, Cr content changed between 1.32 and 4.20 ppm.     

Comparative Investigations on Optimum Polymerization Conditions for the Synthesis of a Sustainable Poly(Lactic Acid)

The development of synthetic biodegradable polymers using solvent free polymerization has a unique potential to be used as sustainable polymers in biomedical applications. The aim of this work was to synthesize and characterize a sustainable class of poly(lactic acid) (PLA) under different operating conditions via direct polycondensation of lactic acid (LA). Several parameters were tested including the absence of solvents and catalysts on the polymerization, in addition to polymerization temperature and time. Polymerization conditions were evaluated using response surface method (RSM) to optimize the impact of temperature, time, and catalyst. Results showed that molecular weight (M_w) of PLA increased with increasing polymerization time. Highest M_w of 28.4 kD with relatively a broad polydispersity 1.9 was achieved at polymerization temperature 170?°C at 24 h in the free solvent polymerization. This led to a relevant inherent viscosity of 0.37 dl/g. FTIR spectra exhibited a disappearance of the characteristic peak of the hydroxyl group in LA at 3482 cm^?1 by increasing the intensity of carbonyl group. The ¹H nuclear magnetic resonance (NMR) exhibited the main chain at 5.22 ppm and the signal of methyl proton at 1.61 ppm as well as a signal at 4.33 and 1.5 assigned to the methane proton next to the terminal hydroxyl group and carboxyl group respectively. Meanwhile, the PLA synthesized with a catalyst [Sn(Oct)₂] in a free solvent demonstrated comparatively high thermal transition properties of glass transition, melting, and crystallinity temperatures of 48, 106, and 158?°C, respectively. These results are of significant interest to further expand the use of PLA in biomedical applications.     

Growth and physiological response of spinach to various lithium concentrations in soil

Environmental Science and Pollution Research - Lithium (Li) exploitation for industrial and domestic use is resulting in a buildup of the element in various environmental components that results in...     

Biogeochemical transformation of greenhouse gas emissions from terrestrial to atmospheric environment and potential feedback to climate forcing

Environmental Science and Pollution Research - Carbon dioxide (CO2) is mainly universal greenhouse gas associated with climate change. However, beyond CO2, some other greenhouse gases (GHGs) like...     

Atmospheric concentrations and phase partitioning of polybrominated diphenyl ethers (PBDEs) in Izmir, Turkey

Atmospheric concentrations of 7 PBDE congeners (BDE-28, -47, -99, -100, -153, -154 and -209) were determined at four sites (i.e. Suburban, Urban 1, Urban 2, Industrial) in Izmir, Turkey and their gas/particle partitioning was investigated. Total PBDE ( summation operator(7)PBDE) concentrations ranged between 11 (Urban 1) and 149pgm(-3) (Industrial) in summer, while in winter, they ranged from 6 (Suburban) to 81pgm(-3) (Industrial). BDE-209 was the dominant congener at all sites, followed by BDE-99 and -47. Investigation of source profiles indicated that the air samples were dominated by congeners of the penta and deca-technical BDE mixtures. The measured PBDE particle fractions were compared to the predictions of the K(OA) (octanol-air partition coefficient)-based equilibrium partitioning model and to the dynamic uptake model developed by others for passive samplers, which was adapted to model gas-particle partitioning in this study. For BDE-28, good agreement was observed between the experimental particle fractions and those predicted by the equilibrium partitioning model. However, this model overestimated the particle fractions of other congeners. The predictions of the dynamic uptake model supported the hypothesis that the unexpectedly high partitioning of BDEs (except BDE-28) to the gas-phase is due to their departure from equilibrium partitioning. When congeners with very large octanol-air partition coefficients (i.e. BDE-100, -99, -154, -153, and -209) are emitted from their sources in the gas-phase, they may remain in that phase for several months before reaching equilibrium with atmospheric particles. This may also have important implications for the transport of atmospheric PBDEs. For example, in addition to particle-bound transport, the gas-phase transport of highly brominated congeners (i.e. BDE-209) may also be important.