In this work, a method for preparing activated carbon based on cherry kernel shell (AC-CKS) was investigated using two consecutive steps: chemical activation with H2SO4 agent and thermal activation in air. For the first time, AC-CKS product is used for the removal of numerous metal ions such Cr(III), Mn(II), Fe(III), Ni(II), Cu(II), Zn(II), and Pb(II) from water solutions. The AC-CKS was characterized using EA, FTIR, SEM, EDX, and XRF techniques. The AC-CKS obtained by heating at 600 degrees C showed products with higher iodine numbers and invariably micro-size pores compared to those obtained by heating at 55 degrees C and 400 degrees C. The adsorption capacity of AC-CKS600 was tested in the removal of previously mentioned metal ions. The essential parameters affecting the removal of metal ions were studied. The results showed maximum adsorption of 99.0% for Cr(III), 91.7% for Fe(III), 62.0% for Cu(II), 59.3% for Pb(II), 42.0% for Zn(II), 28.0% for Ni(II), and 26.9% for Mn(II). The adsorption data of most metal ions fitted well with Langmuir model. The maximum adsorption capacity followed the sequence: Cr(10.75mg/g)>Fe(10.15mg/g)>Cu(7.58mg/g)>Pb(7.36mg/g)>Zn(6.08mg/g)>Ni(2.83g/g)>Mn(2.29 mg/g). The adsorption kinetics was tested for the pseudo-first order and pseudo-second order. The rate constants of adsorption for all studied metal ions were calculated. Good correlation coefficients (R-2>0.9972) were obtained for the pseudo-second-order kinetic model showing that all metal ions uptake processes followed the pseudo-second-order rate expression. Desorption studies showed the quantitative recovery of metal ions in the range of 89.4% for Pb(II) to 94% for Cr(III). According to the adsorption model applied in this work, AC-CKS600 product could be recommended for the removal of Cr(III), Fe(III), Cu(II), Pb(II), and Zn(II) from aqueous solutions.

Several types of apricot kernel cultivated in Syria were used in this study in order to clarify differences in their thermal and chemical properties. Chemical and thermal properties were monitored by FTIR, DSC, TGA techniques. Chemical analysis showed that all types of kernel shells from different sources possessed the same structure. However, the thin brown layer (skin) that covers the kernel had some chemical structure differences in comparison to its shell. The decomposition of the kernel shell showed three steps of degradations at 75, 260 and 450 °C related to the removal of water, degradation of cellulose and lignin, respectively. Additional step was observed at ~ 178 °C in particles smaller than 250 µm related to the removal of incorporated water. The kernel skin showed the same thermal properties in degradation with shifting to lower temperature.

Water from a single natural spring filled in PET has been used to examine the sterilization effect of Gamma and E-Beam irradiation on the chemical and microbial quality of water through 6 months of storage under real consumer conditions. Two strategies were adapted in this work; the first was the sterilization of PET empty bottles at 20 kGy dose which were then filled by UV sterilized water. The second was the sterilization of the PET bottled water at the recommended microbial decontamination dose of 5 kGy. Dibutyl phthalate, diethyl phthalate, and dimethyl phthalate concentrations increased significantly during storage under sunlight exposure in comparison with a dark laboratory storage. Nitrite was only presented in PET bottled water that was sterilized by Gamma irradiation and stored in the dark. 5 kGy dose could be considered good for microbial sterilization of PET bottled water and has less impact on leaching of phthalates compounds than 20 kGy dose. Moreover, it could be an emergent method for water decontamination at an industrial level and consequently improve the public health.

Semi-crystalline polyethylene terephthalate (PET) was aged under the effect of natural UV exposure and outdoor temperature during 670 days. The variation in the mechanical and thermal properties beside to the morphology was tracked by applying different analytical techniques, including scanning electron microscopy, infrared spectroscopy, differential scanning calorimetry and wide angle X-ray diffraction, in addition to tensile strength and hardness measurements. It has been confirmed that the ageing process is the results of physical trend only. The aged PET showed a decrease in both tensile strength and strain with an increase in the degree of crystallinity of aged PET samples during the whole period. These changes in crystallinity were examined by various analysis methods: density, calorimetric and infrared spectroscopy. New peaks in FTIR analysis at 1115 and 1090 cm−1 were characterized and proved that this technique is considered to be an easy tool to track the change in the surface crystallinity of aged PET samples directly. The results of this study showed that an augmentation in the degree of crystallinity of outdoor aged PET samples from 18 to 36 %, accompanied with a decrease in tensile strength from 167.9 to 133.7 MPa. Moreover, a good exponential correlation was found between the degree of crystallinity and the mechanical properties of the aged PET.

Polyethylene terephthalate bottles containing natural spring water were used to study the leaching effect of carbonyl compounds after one year storage under real conditions of exposure. Ultraviolet-B and ultraviolet-A spectra of direct sunlight were acquired during the experiment. Leaching of acetone, acetaldehyde, and formaldehyde reached steady state after 210days of outdoor storage, with the following concentrations: 434 +/- 22, 345 +/- 18, and 94 +/- 5 mu g/L, respectively. The increase due to sunlight exposure in comparison with laboratory storage in the dark was around 10%, 16%, and 36%. The leaching process of all three carbonyl compounds was found to follow the first-order kinetics. Photo-degradation of Polyethylene terephthalate bottles and the appearance of carboxyl end-groups were followed by attenuated total reflectance infrared spectra. After 313days of storage under direct sunlight, new peaks appeared in the regions of 1770-1920 cm(-1) and 1685-1490 cm(-1). Cations, anions, total dissolved solids, pH, and conductivity were also measured during the storage period. Additionally, microbiological measurements as well as statistical analyses were also carefully discussed.

ABSTRACTAttenuated total reflection Fourier transform infrared (ATR‐FTIR) and two‐dimensional correlation (2D‐COS) spectroscopies were utilized to probe the structural changes occurring upon sunlight ageing up to 6 months in air atmosphere of both control and sterilized poly(ethylene terephthalate), (PET) bottles.Two dominant reactions were found; namely oxidation of the carbonyl groups and trans to gauche transformation of the ethylene glycole units. Oxidation manifested itself by the progressive development of a distinct band at 1690 cm−1assigned to the antisymmetric stretching of the carbonyl band in an aromatic carboxylic acid. Sterilizing the bottles by E‐beam or Gamma rays prior to ageing reduced the correlation intensity of the band at 1690 cm−1, and led to the presence of higher molecular weight compounds such as terephthalic acid in stored water. The infrared spectroscopy combined with 2D‐COS provides a powerful tool to investigate chemical and stero‐chemical modification of polymers. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44736.

Potato tubers were irradiated in Co-60 gamma station at different doses in order to investigate the effect of gamma irradiation on acrylamide formation in fried potato strips. Acrylamide content due to the irradiation treatment was reduced by 20-54% compared to a control after frying the irradiated tubers. While apply a blanching process, using warm tap water, to potato strips before frying has decreased acrylamide by 61%. A combination of gamma irradiation and a blanching process, which was applied in this work, showed a maximum decrease in acrylamide formation to reach 78% in fried potatoes.

The effect of two environmental variables, ultraviolet radiation and external air temperature, on polyethylene terephthalate (PET) bottled water was investigated over 100 days. The high pressure liquid chromatography results showed the migration of carbonyl compounds (acetaldehyde, formaldehyde and acetone) from PET bottles into water over 3 months. Storage of PET bottled water enhanced the process of carbonyl compounds migration especially under sunlight. The combination of these two environmental variables caused an increase of 15% in each carbonyl compound compared with storage in the dark at the laboratory. The maximum ambient Ultraviolet-B, Ultraviolet-A and Photo-synthetically Active Radiation intensity at the solar noon were 1.95, 23.0 W/m(2) and 100,000 Lux, respectively.

The effects of phototransformation of dissolved organic matter (DOM) on bacterial growth, production, respiration, growth efficiency, and diversity were investigated during summer in two lagoons and one oligotrophic coastal water samples from the Northwestern Mediterranean Sea, differing widely in DOM and chromophoric DOM concentrations. Exposure of 0.2-μm filtered waters to full sun radiation for 1 d resulted in small changes in optical properties and concentrations of DOM, and no changes in nitrate, nitrite, and phosphate concentrations. After exposure to sunlight or dark (control) treatments, the water samples were inoculated with the original bacterial community. Phototransformation of DOM had contrasting effects on bacterial production and respiration, depending on the water's origin, resulting in an increase of bacterial growth efficiency for the oligotrophic coastal water sample (120%) and a decrease for the lagoon waters (20 to 40%) relative to that observed in dark treatments. We also observed that bacterial growth on DOM irradiated by full sun resulted in changes in community structure of total and metabolically active bacterial cells for the three locations studied when compared to the bacteria growing on un-irradiated DOM, and that changes were mainly caused by phototransformation of DOM by UV radiation for the eutrophic lagoon and the oligotrophic coastal water and by photosynthetically active radiation (PAR) for the mesoeutrophic lagoon. These initial results indicate that phototransformation of DOM significantly alters both bacterial metabolism and community structure in surface water for a variety of coastal ecosystems in the Mediterranean Sea. Further studies will be necessary to elucidate a more detailed appreciation of potential temporal and spatial variations of the effects measured.

Growth experiments on the marine bacterium Vibrio angustum S14 were conducted under four light conditions using a solar simulator: visible light (V), V + ultraviolet A (UV-A), V + UV-A + UV-B radiation, and dark. Growth was inhibited mainly by UV-B and slightly by UV-A. UV-B radiation induced filaments containing multiple genome copies with low cyclobutane pyrimidine dimers. These cells did not show modifications in cellular fatty acid composition in comparison with dark control cultures and decreased in size by division after subsequent incubation in the dark. A large portion of the bacterial population grown under visible light showed an alteration in cellular DNA fluorescence as measured by flow cytometry after SYBR-Green I staining. This alteration was not aggravated by UV-A and was certainly due to a change in DNA topology rather than DNA deterioration because all the cells remained viable and their growth was not impaired. Ecological consequences of these observations are discussed.

The high content in nutrients of freshwater outflows induces highly productive and buoyant plumes spreading over marine waters (MW). As a consequence, the growth of organisms developing in these low-salinity waters (LSW) might be potentially affected by UV-R (280-400 nm). This study investigated the penetration of UV-R and its impact on net community production (NCP) and bacterial protein (B(PROT)S) and DNA (B(DNA)S) synthesis in mesotrophic-LSW formed from the Rhone River and in oligotrophic MW of the Northwestern Mediterranean Sea (Gulf of Lions) in May 2006. High concentrations of chlorophyll a (up to 8 mu g L(-1)) measured in the LSW (< 37.8 psu, 0-10 m) were the main factor influencing the diffuse attenuation coefficients (K(d)) of both UV-R and photosynthetically active radiation (PAR). The mean ratio of the K(d) measured between the LSW and the MW increased with wavelength from 2.4 at 305 nm to 2.9 at 380 nm and 3.1 for PAR indicating more similarity in the UV region. NCP was severely inhibited by UV-R at the surface of the LSW, whereas no effect was measured in the surrounding MW. In contrast, B(PROT)S and B(DNA)S were affected deeper by UV-R in the MW (up to 8 m depth) compared to the LSW where inhibition was only observed at the surface. Differences in response of bacteria in LSW and MW are largely explained by differences in UV-R transparency; however, transplant experiments indicate that bacterial assemblages from the MW were also more sensitive to UV-R than those present in the LSW. We also observed that higher activity of bacteria after nutrient additions increased their sensitivity to UV-R during the day, but favored their recovery during the night incubation period for both LSW and MW. Results suggest that riverine and nutrient inputs may alter the effects of UV-R on microbial activity by attenuating the UV-R penetration and by modifying the physiology of bacteria.