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A Pulsed Electrical Field (PEF) reactor was developed to process biological sludge as a pretreatment method prior to anaerobic digestion. This study focuses on the effects of operational parameters such as applied voltage, pH, conductivity, flow-rate, and temperature affecting the treatment of waste active sludge (WAS) by PEF, the simulation of reactor process conditions and anaerobic biodegradation of PEF pretreated sludge. The effects of the sludge conductivity, flow-rate, and temperature on the Soluble Chemical Oxygen Demand (SCOD) of WAS treated by PEF reactor were investigated by using a Box-Wilson statistical experiment design. Simulations of the PEF process conditions were performed to verify experimental results. After PEF optimization study, the PEF operational conditions for maximum SCOD were obtained at 4 mS/cm conductivity, 5 mL/min flow-rate, and 40 degrees C temperature during PEF treatment. The measured and predicted SCOD showed a good consistency (R (2 )= 0.92). After it was pretreated by the PEF, the SCOD, total nitrogen, total phosphorus, polysaccharide and protein contents of WAS increased. However filterability property also decreased. In the anaerobic digestion study, the reactor fed with the PEF pretreated WAS provided 1.70 times higher methane production compared with raw sludge. In addition to this situation, 18% and 19% improvements, respectively, were observed in SCOD and VSS reductions when it was compared with raw sludge in the 23 days of anaerobic operation. Sixteen percent decrease in CST showed that the PEF enhanced the ?lterability of WAS during the anaerobic stabilization.

Biyolojikarıtma çamurları organik madde, azot ve fosfor içeriği yönünden zengin birkaynaktır. Bu nedenle tarımda kullanımı oldukça önemlidir. Magnezyum amonyumfosfat (MAP) çöktürmesi sonucu elde edilen strüvit, endüstriyel hammadde vetarımsal gübre olarak kullanım için uygundur. Arıtma çamurlarından azot vefosfor geri kazanımı için kullanılan yöntemlerin başında asidik şartlarda azotve fosforun sıvı faza geçirilmesi gelmekte ve akabinde MAP çökelmesi ilestrüvit elde edilmesi sağlanmaktadır. Bu yöntem için en büyük sorunasidifikasyon işlemi ile sıvı faza geçen ağır metallarin strüvitebağlanmasıdır. Çalışmamızda yeni bir çamur dezentegrasyon yöntemi darbelielektrik alan (PEF) tekniği ile evsel nitelikteki biyolojik atık çamurdan azotve fosfor geri kazanımı gerçekleştirilmiştir. Çalışma iki aşamadanoluşmaktadır. Birinci aşama; biyolojik atık çamurdaki azot ve fosforun kimyasaleklemeden PEF tekniği ile geri kazanımı. İkinci aşama ise PEF ön arıtımısonrası sıvı fazda elde edilen yüksek azot ve fosfordan MAP çöktürmesi ilestrüvit elde edilmesi şeklindedir. MAP çökeltim testlerinde optimum sıcaklık,pH ve çökelme süresi sırasıyla 20 °C, 9.5 ve 24 saat olarak belirlenmiştir. Eniyi çökelme ve giderim verimi 2.5 ml MgCl2.6H2O (0.015 M)ve 2.5 ml H3PO4 (0.049M) eklenmiş örnekte elde edildi.Çökeltim sonrası TN ve TP giderim verimleri sırasıyla %52 ve %14’tür. Çökeltimsonrası kristal yapılı çökelti oluşumu gözlenmiş ve XRD analizi sonucunda buçökeltinin strüvit olduğu tespit edilmiştir., Sewagesludge is a rich source of organic matter, nitrogen and phosphorus content. Forthis reason, its use in agriculture is very important. Strüvite obtained as aresult of magnesium ammonium phosphate (MAP) settlement is suitable for use asindustrial raw material and agricultural fertilizer. At the beginning of themethods used for the recovery of nitrogen and phosphorus from sludge, nitrogenand phosphorus are introduced into liquid phase under acidic conditions. Thenthe struvite is obtained by MAP precipitation. The biggest problem for this method is the bonding ofheavy metals passing liquid phase by acidification to struvite. In our work, a new sludge disintegration method,pulsed electric field (PEF) technique, has been used to recover nitrogen andphosphorus from the domestic biological waste sludge. The study consists of twophases. In the first stage, nitrogenand phosphorus from biological waste sludge are recovered without the additionof chemical by PEF technique. Inthe second stage, the strüvite is obtained by MAP precipitation from liquidphase with high nitrogen and phosphore content. The optimumtemperature, pH and precipitation time were determined as 20 °C, 9.5 and 24 hours, respectively for the formation of strüvite in the MAP precipitation tests. Thebest precipitate and removal efficiency was obtained to the sample with 2.5 mlof MgCl2.6H2O (0.015 M) and 2.5 ml of H3PO4(0.049M). TN and TP removal efficiencies were obtained as 52% and 14% afterprecipitation. After sedimentation, crystalline precipitate formation wasobserved and XRD analysis revealed that this precipitate was struvite.

In the current work, the effect of the poly(2-aminoethyl methacrylate)-grafted kaolin (PAEMA@KLN) was investigated for the potential removal of U(VI) from aqueous samples. This novel adsorbent prepared for U(VI) removal was characterized by various techniques (Fourier transform infrared spectrometry (FTIR), energy-dispersive x-ray analysis (EDX), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS)). Response surface methodology (RSM) was utilized to optimize and model the removal of U(VI) by PAEMA@KLN from aqueous environments. The effects of different parameters such as pH, U(VI) concentration ( C o ), PAEMA@KLN dosage, and shaking time were optimized by central composite design (CCD) combined with RSM. The optimum points were numerically determined as 5.07 for pH, 35.16 mg/L for C o , 13.73 mg for PAEMA@KLN dosage, and 92.09 min for the shaking time. The maximum removal was obtained at 96.03% under the optimum conditions. The kinetic data was better described by the pseudo-second-order and Weber–Morris models. U(VI) removal onto PAEMA@KLN follows the Langmuir isotherm model. Thermodynamic studies showed that U(VI) removal by PAEMA@KLN was spontaneous and exothermic in nature. The results indicate that PAEMA@KLN is a promising adsorbent for the effective removal of radionuclides like U(VI) from aqueous media.

This study deals with radioactivity and heavy metal distribution and statistical analyses in the Bendimahi River Basin, which is within the Lake Van Closed Basin, Turkey. In order to identify the relationships between measured variables and to categorize soils and sediments collected at 15 sites on Bendimahi River, factor and cluster analysis have been applied. The data set is constituted of 9 radiological and physico–chemical variables, including gross alpha and gross beta activities and Pb, Zn, Cu, Cr, Cd, Co and Mn concentrations. Factor and cluster analysis were used to describe the relationship and similarity among data sets (variables) for the Bendimahi River. The convergence diagnostics such as trace plot and kernel density were applied to determine the convergence criteria to the data sets.

In this study, the performance of modified adsorbents obtained from activated carbon for the adsorption of thorium(IV) ions from aqueous media was investigated. The analytical and spectroscopic methods such as FT-IR, BET, SEM and UV-Vis were used to examine the properties of the modified materials. According to the analysis results, the both adsorbents had large surface areas after modification. Then, temperature, pH, mixing time and solution concentration parameters were observed to determine optimum thorium adsorption conditions on modified materials. The obtained results from the experiments were applied different three kinetic models and adsorption isotherms and thermodynamic parameters were calculated and then all of the results were interpreted. The adsorption process for both adsorption systems was observed to be compatible with the pseudo-second-order kinetic model. The adsorption equilibrium data were best described by the Langmuir model for modified adsorbent with KMnO4 and by the Freundlich model for modified adsorbent with NaOH. Furthermore, the calculated thermodynamic parameters (Delta G degrees, Delta H degrees and Delta S degrees) showed that the both adsorption processes were endothermic and spontaneous. The data show that modified adsorbents can be used as influential and low-cost adsorbents to remove thorium ion. Modified new adsorbents were highly selective for thorium ion in competitive adsorption studies.

The natural gross radioactivity in milk from farms in different locations in Van and in milk purchased from Kahramanmara markets were determined. In the milk samples, natural gross alpha and beta activity concentrations were measured. The evaporation and ashing procedures were applied to the milk samples collected from farms and markets. Nuclear spectroscopic systems containing gas-flow proportional counters were used to measure the gross alpha and beta activity concentrations of the milk samples. The gross radioactivity in milk from markets was generally lower than the gross radioactivity in milk from farms. The annual effective dose resulting from gross radioactivity for adults, children, and infants and excess lifetime cancer risk values were calculated. The highest total annual effective dose (AED) values were 1,105.9mSvy-1 for adults, 6,456.2mSvy-1 for children, and 10,267.0mSvy-1 for infants in milk samples. The excess lifetime cancer risk (ELCR) values from gross alpha and beta activities range from 0.010 to 3.870 in milk samples.

Contamination of agricultural soil is a worldwide problem, with heavy metals being a major part of the concern. Bioenergy crop production is also a profitable phytoremediation strategy using biofuel crops for both utilization and remediation of contaminated soil. To investigate lead (Pb) accumulation and tolerance of three different energy crop cultivars, three-week-old healthy seedlings were grown in Hoagland solution supplemented with five different concentrations of Pb 0, 25, 50, 100, and 150 mg/kg. At the end of 30 days, Pb content and translocation, tolerance index, bioconcentration factor, and growth parameters of the plants were evaluated in the study. Results showed that increasing Pb concentrations did not affected the growth and development of Sunburst (Panicum virgatum L.) and Dincer (Carthamus tinctorius L.) cultivars. The highest Pb contents were also found in roots and shoots of Sunburst and Tarsan-1018 (Helianthus annuus L.) cultivars. Dincer cultivar has a high ability to transfer Pb from root to shoot when compared to others. These results suggest that these cultivars may be good candidates for remediation of Pb-contaminated areas for use in biofuel production.

Many kinds of cosmetic products were analyzed to determine gross radioactivity. In this study, gross alpha/beta radioactivity concentrations in 51 cosmetic samples were determined. The examined cosmetic products consist of blusher, eye shadow, lipstick, nail polish, shampoo, hand cream, cellulite cream, baby powder, soap, and toothpaste. The gross alpha–beta activity concentrations were measured with a nuclear spectroscopic system which contains gas-flow proportional counters. The highest gross alpha/beta activity concentrations were found in eye shadow samples of 1.621Bq g−1 for alpha and 6.471Bq g−1 for beta. The total effective doses due to gross radioactivity for skin were calculated. Although the effective dose of eye shadow samples had the highest value, the effective doses due to gross radioactivity concentrations in this study were found to be lower than the radiological limits given by the authorities.

In this study, a new cationic monomer 2-(3-indol-yl)ethylmethacrylamide (IEMA) derived from tryptamine was synthesized in a single step and characterized by Fourier transform infrared (FTIR), H-1-NMR, and C-13-NMR. Then, one-step preparation of novel poly[2-hydroxyethylmethacrylate-c-2-(3-indol-yl)ethylmethacrylamide], or p(HEMA-c-IEMA), copolymeric hydrogels has been performed successfully with IEMA and 2-hydroxyethylmethacrylate (HEMA) as monomers using free radical aqueous polymerization. The hydrogels were characterized with scanning electron microscopy, FTIR, elemental analysis, thermogravimetric analysis, and texture profile analysis instruments. p(HEMA-c-IEMA) hydrogels were used for swelling, diffusion, drug release, and antibacterial activity studies. The drug-release behavior of the hydrogels was determined as a function of time at 37 degrees C in pH1.2 and 7.2. The swelling and drug-release studies showed that an increased IEMA amount caused a higher increase in swelling and drug-release values. Additionally, zero-order, first-order, and Higuchi equation kinetic models were applied to the drug-release data, and the data fit well in the Higuchi model, and the Peppas power-law model was applied to the release mechanism. Finally, the antibacterial activities of the hydrogels were screened against Gram-positive bacteria (Bacillus cereus and Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli and Salmonella typhimurium). (c) 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45550.

As part of the national survey to evaluate natural radioactivity in the environment, concentration levels of total radioactivity and natural uranium have been analysed in drinking water samples. A survey to study natural radioactivity in drinking waters was carried out in the Van province, East Turkey. Twenty-three samples of drinking water were collected in the Van province and analysed for total α, total β and (238)U activity. The total α and total β activities were counted by using the α/β counter of the multi-detector low background system (PIC MPC-9604), and the (238)U concentrations were determined by inductively coupled plasma-mass spectrometry (Thermo Scientific Element 2). The samples were categorised according to origin: tap, spring or mineral supply. The activity concentrations for total α were found to range from 0.002 to 0.030 Bq L(-1) and for total β from 0.023 to 1.351 Bq L(-1). Uranium concentrations ranging from 0.562 to 14.710 μg L(-1) were observed in drinking waters. Following the World Health Organisation rules, all investigated waters can be used as drinking water.

The gross alpha and gross beta activity concentrations were measured in human tooth taken from 3 to 6 age-groups to 40 and over ones. Accumulated teeth samples are investigated in two groups as under and above 18 years. The gross alpha and beta radioactivity of human tooth samples was measured by using a gas-flow proportional counter (PIC-MPC 9604-alpha/beta counter). In tooth samples, for female age-groups, the obtained results show that the mean gross alpha and gross beta activity concentrations varied between 0.534-0.203 and 0.010-0.453 Bq g(-1), and the same concentrations for male age-groups varied between 0.009-1.168 and 0.071-0.204 Bq g(-1), respectively. (C) 2009 Elsevier Ltd. All rights reserved.

A laboratory scale anaerobic migrating blanket reactor (AMBR) was operated at different HRTs (1–10.38 days) in order to determine the para -nitrophenol ( p -NP) and COD removal kinetic constants. The reactor was fed with 40 mg L −1 p -NP and 3000 mg L −1 glucose-COD. Modified Stover-Kincannon and Grau second-order kinetic models were applied to the experimental data. The predicted p -NP and COD concentrations were calculated using the kinetic constants. It was found that these data were in better agreement with the observed ones in the modified Stover-Kincannon compared to Grau second-order model. The kinetic constants calculated according to Stover-Kincannon model are as follows: the saturation value constant ( K B ) and maximum utilization rate constants ( R max ) were found as 31.55 g COD L −1 day −1 , 29.49 g COD L −1 day −1 for COD removal and 0.428 g p -NP L −1 day −1 , 0.407 g p -NP L −1 day −1 for p -NP removal, respectively ( R 2 = 1). The values of ( a ) and ( b ) were found to be 0.096 day and 1.071 (dimensionless) with high correlation coefficients of R 2 = 0.85 for COD removal. Kinetic constants for specific gas production rate were evaluated using modified Stover-Kincannon, Van der Meer and Heerrtjes and Chen and Hasminoto models. It was shown that Stover-Kincannon model is more appropriate for calculating the effluent COD, p -NP concentrations in AMBR compared to the other models. The maximum specific biogas production rate, G max , and proportionality constant, G B , were found to be 1666.7 mL L −1 day −1 and 2.83 (dimensionless), respectively in modified Stover-Kincannon gas model. The bacteria had low Haldane inhibition constants ( K ID = 14 and 23 mg L −1 ) for p -NP concentrations higher than 40 mg L −1 while the half velocity constant ( K s ) increased from 10 to 60 and 118 mg L −1 with increasing p -NP concentrations from 40 to 85 and 125 mg L −1 .

The levels of heavy metals were determined in the water of Bendimahi River Basin, statistically analysed and compared to natural gross radioactivity concentration. Fifteen samples of water were collected from Bendimahi River and Van Lake for two seasons in 2005. Water samples were analyzed for eight trace elements and concluded together with gross-alpha and gross-beta radioactivity concentrations. Atomic absorption spectrometry (AAS) was used to determine the concentrations of heavy metals in water samples collected from Bendimahi River basin. Correlation analysis was made for radioactivity and heavy metal concentrations and the Pearson correlation coefficients between gross-alpha and gross-beta radioactivity and heavy metal were determined. The concentrations of all metals were found to be higher than WHO, EC, EPA and TSE-266 guidelines for drinking water, except for Zn and Cu. Generally, the heavy metal concentrations in water samples obtained in May and in August were found to be in sequence of Fe>Zn>Pb>Cr>Cu>Mn>Co>Cd and Fe>Zn>Cu>Pb>Cr>Mn>Co>Cd, respectively. The gross-alpha and gross-beta activity concentration varies between 0.063 and 0.782, 0.021 and 0.816 Bq 1(-1) in samples collected in May, and 0.009 and 0.037, 0.081 and 3.116 Bq 1(-1) in samples collected in August.

In this study the anaerobic treatability of p -nitrophenol ( p -NP) was investigated in an anaerobic/aerobic sequential reactor system under increasing organic loadings during operation period of 186 days. Lab-scale anaerobic migrating blanket reactor (AMBR)/completely stirred tank reactor (CSTR) system consisted of effective volumes of 13.5 and 9 L, respectively. Synthetic wastewater was obtained from constant p -NP concentration of 40 mg/L and a glucose concentration giving 3000 mg/L COD as primary substrate. The studies were carried out in continuous mode and the effluent of the AMBR reactor was used as the feed for the CSTR reactor. The AMBR/CSTR reactor system was operated at organic loading rates (OLRs) increasing from 0.31 to 3.25 kg/m 3 day. COD and p -NP removal efficiencies were decreased from 92% to 79% and from 94% to 86%, respectively, when the COD loading rates were increased from 0.31 to 3.25 kg/m 3 day in AMBR. The total COD and p -NP removal efficiencies were 94% and 91% in whole (AMBR/CSTR) reactor system, at a COD loading rate of 3.25 kg/m 3 day, respectively. The total gas and methane gas production increased with increased OLRs. The daily total and methane gas productions were 12.25 and 3.8 L/day at OLR of 3.25 kg/m 3 day, respectively. Methane gas percentage was also found as 31% at this loading rate. In this study, pH, total volatile fatty acid (TVFA) and bicarbonate alkalinity (BA)/total volatile fatty acid (TVFA) ratios variations in the effluent and in the all compartment of the AMBR were suitable for optimal anaerobic treatment at all OLRs. The pH, TVFA and BA/TVFA ratios in the effluent and in all the compartments of the AMBR were obtained between 7.2–7.64, 290–353 mg/L and 0.06–0.13, respectively, at OLR of 3.25 kg/m 3 day. A 79–92% of the p -NP transformed to p -amino phenol ( p -AP) in anaerobic phase. The generation of phenol and ammonia (NH 4 -N) was observed during the anaerobic degradation. A complete mineralization of p -AP ( E = 100%) was found in the aerobic phase. The p -AP, phenol and NH 4 -N were converted to nitrite (NO 2 -N), nitrate (NO 3 -N) and CO 2 as end products in the aerobic step.

The effects of increasing nitrobenzene (NB) concentrations and hydraulic retention time (HRT) on the performance of anaerobic baffled reactor (ABR) and aerobic completely stirred tank reactor (CSTR) were studied. In the first step the NB concentration was increased from 30 to 700 mg/L at constant COD and flowrates. Maximum COD removal efficiencies in ABR varied between 88–92% as NB concentrations increased from 30 to 210 mg/L. After this dose, COD removal efficiency decreased to 85 and 79% at NB concentrations of 550 and 700 mg/L, respectively. Removal efficiencies of NB were nearly 100% for all NB concentrations in ABR reactor effluent. In the second step, COD and NB concentrations were kept constant while HRT decreased from 10.38 days to 1 day. As HRT decreased from 10.38 to 2.5 days the COD removal efficiencies in the anaerobic and anaerobic/aerobic reactor effluents were 92–94% and 97–98%, respectively. As HRT decreased from 2.5 days to 1 day COD removal efficiencies in the anaerobic and anaerobic/aerobic reactor effluents decreased to 83 and 95%, respectively. This study showed that HRT is a more important operation parameter than increasing NB concentration in ABR /CSTR sequential reactor system. Although ABR/CSTR system exhibited good COD and NB removal efficiencies, the lower HRTs slightly decreased the removal efficiencies compared to increasing NB concentration.

In this study, physical and thermodynamic properties of poly(2-phenyl-1,3-dioxolane-4-yl-methyl-methacrylate-co-styrene) (PDMMA-ST) were investigated by using inverse gas chromatography. Two groups of solvents with different chemical natures and polarities were used to obtain information about PDMMA-ST-solvent interactions: alcohols and alkanes. The specific retention volume (V-g(0)), the sorption enthalpy (Delta H-1(S)), sorption free energy (Delta G(1)(S)), sorption entropy (Delta S-1(S)), the weight fraction activity coefficients of solute probes at infinite dilution (Omega(infinity)(1)), and Flory-Huggins interaction parameters (chi(infinity)(12)) between polymer and solvents were determined for the interactions of PDMMA-ST with alcohols and alkanes by inverse gas chromatography in the temperature range of 333-473 K. Also, the solubility parameters of PDMMA-ST at infinite dilution were found by plotting the graph of [(delta(2)(1)/RT) - chi(infinity)(12)/V-1] versus solubility parameters, delta(1), of probes.

In this study, the effect of increasing p-nitrophenol (PNP) concentrations on the performance of anaerobic baffled reactor (ABR) (chemical oxygen demand (COD), removals, volatile fatty acid (VFA), p-aminophenol (PAP) and methane gas productions) was investigated through 240 days. The PNP concentrations were raised to 700 from 10 mg/L corresponding to PNP loading rates of 0.97 and 67.9 g/m(3) day. The PNP and COD removal efficiencies were 99 and 90% at PNP loading rates as high as 33.9 g/m(3) day, respectively, through the acclimation of anaerobic granular sludge. After this loading rate, the removal efficiencies decreased to 79%. The COD removal efficiencies were high in compartment 1 (E = 78-93%) while a small amount of COD removal was achieved in compartments 2 and 3. The PNP removal efficiencies were approximately 90% in all PNP loading rates except for loading rate of 0.97 g/m(3) day. The maximum PNP removal efficiency was measured as 99% at a loading rate of 8.32 g/m(3) day. The optimum PNP loading rate for maximum COD, PNP removals and methane yield was 8.32 g/m(3) day. The total, methane gas productions and methane percentages were approximately 2160-2400 mL/day and 950-1250 mL/day and 44-52% for the PNP loading rates varying between 4.36 and 33.9 g/m(3) day, respectively. For PNP loading rates varying between 33.9 and 67.9 g/m(3) day, the total, methane gas productions and methane percentages were approximately 2160 and 960 mL/day and 44%, respectively. The highest total volatile fatty acid (TVFA) concentrations were found in the first compartment with fluctuated values varied between 50 and 200 mg/L indicating the acidogenesis. p-Aminophenol was found as the main intermediate through anaerobic degradation of PNP which later was broken down to phenol and ammonia. (c) 2005 Elsevier Inc. All rights reserved.

In this study, the anaerobic treatability of p-nitrophenol (p-NP) was investigated in an anaerobic/aerobic sequential reactor system. During the anaerobic stage the target compound is modified via degradation and then the intermediate product is more readily biodegradable by the aerobic phase. Lab-scale anaerobic migrating blanket reactor (AMBR) and a completely stirred tank reactor (CSTR) were used sequentially to investigate the treatability of p-nitrophenol using glucose as primary substrate in continuous fed mode. The COD removal efficiency of synthetic wastewater containing no p-NP was between 90 and 95% after 45 days of the start-up period. The effects of increasing p-NP concentrations on bicarbonate alkalinity, volatile fatty acid accumulation, and methane gas percentage were obtained in AMBR reactor while, NO2-N, NO3-N, NH4-N were monitored as final metabolic products in aerobic CSTR reactor. COD and p-NP removal efficiencies of 94 and 95%, were obtained respectively, in AMBR reactor at a loading rate of 3.85 g p-NP/m(3)/day. The maximum methane production rate and methane percentage (approximately 1000 ml/day and 50%, respectively) was obtained at this loading rate. p-NP was transformed to p-aminophenol (p-AP) in the anaerobic phase. Mineralization of p-AP and phenol was determined in the oxidative aerobic stage. The total p-NP and COD removal efficiencies were found as 96 and 97% at loading rate of 3.85 g p-NP/m(3)/day in whole (anaerobic/aerobic) sequential reactor system, respectively. (c) 2004 Elsevier Ltd. All rights reserved.