Jessenallison5478

Microalgae have been considered as promising alternative for CO2 fixation and wastewater purification. In our previous work, a hybrid microalgae CO2 fixation concept has been put forward, which initially used carbonate solution absorb CO2, and then provided obtained bicarbonate as nutrition for microalgae growth to avoid the challenge of low CO2 solubility and carbon fixation efficiency in the conventional process. In this work, the proposed hybrid system was further intensified via integrating soybean wastewater nutrition removal with bicarbonate-carbon (NH4HCO3 and KHCO3) conversion. The investigation results indicated that the maximum biomass productivity (0.74 g L-1) and carbon bioconversion efficiency (46.9%) were achieved in low-NH4HCO3 concentration system with pH adjusted to 7. pH adjustment of different bicarbonate systems also enhanced total nitrogen (TN), total phosphorus (TP) and chemical oxygen demand (COD) removal efficiency up to 87.5%, 99.5% and 77.6%, respectively. In addition, maximum neutral lipid (14.4 mg L-1·d-1) and polysaccharide (14.5 mg L-1·d-1) productivities could be obtained in the KHCO3 systems, while higher crude protein productivity (48.1 mg L-1·d-1) was yielded in the NH4HCO3 systems. KY 12420 solubility dmso Exposure to polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) may change leukocyte telomere length (TL) at the end of the DNA sequence. The purpose of this study was to investigate the association between PCBs and OCPs exposure with TL in Tehran adult males. Whole-blood samples were randomly taken from three hundred adult males in population-based cross-section study from October 2016 to November 2017. We studied the serum levels of PCBs, OCPs as well as socio-demographic characteristics of individuals. The quantitative PCR was used to investigate the number of the telomere (T) repeats to the number of a single copy gene. We measured the effect of each PCBs and OCPs congeners on TL using linear regressions adjusted for age, BMI, smoking, and dietary patterns. The median level of the six non-dioxin-likes, five dioxin-likes PCBs three OCPs and TL in the study population were 344.5, 306.0, 45.0 ng/g lipid and 5377.7 ± 573.4 base pairs, respectively. In the adjusted model, the percent difference in the TLs with exposure to Σnon-dioxin-like PCBs, Σdioxin-like PCBs, and OCPs were 1.93 (-0.70 to 5.4), 3.4 (1.8-8.3) and -2.4 (-0.80 to -6.2), respectively. In the fourth quartile compared to the first quartile, the percent difference in the TLs due to Σnon-dioxin-like PCBs, Σdioxin-like PCBs, and OCP exposure were 0.01 (-0.01 to 0.05), 10.3 (2.9-18.1) and -0.20 (-0.10 to -4.5), respectively. Exposures to ndl-PCBs and dl-PCBs (except for PCB28) were related to longer TLs, but OCPs exposure can be related to telomere shortening. Hormesis is an ecotoxicological phenomenon referred to as the biphasic dose-response effect. At a low concentration of toxic substances, a hormetic stimulating effect occurs, while an inhibitory effect occurs at higher concentrations. The phenomenon of hormesis may hinder the interpretation of toxicity test results and lower the actual toxicity of test samples. In this study, a hormesis phenomenon was observed and analysed during toxicity tests of wastewater from constructed wetlands containing two pharmaceutical substances, diclofenac (DCF) and sulfamethoxazole (SMX), against the marine bacteria Aliivibrio fischeri. To eliminate the hormesis phenomenon, a change in the diluent (ISO 11348-32007) to synthetic sea water (ISO 102532006) is proposed. The hormesis phenomenon was observed only during the analysis of wastewater toxicity with the standard toxicity test (with the diluent). The use of synthetic sea water eliminated the hormetic effects because of the presence of additional components in the sea water, such as MgCl2, Na2SO4, CaCl2, KCl, NaHCO3, and H3BO3, which increased the sensitivity of A. fischeri to the pharmaceutical substances. The use of different media in toxicity tests may have significant effects on the toxicity classification of the tested compounds or wastewater. Additionally, the toxicity of tested pharmaceuticals towards A. fischeri was analysed. The IC50 values of DCF were 8.7 ± 1.1 mg L-1 (for diluent) and 13.9 ± 0.9 mg L-1 (for synthetic sea water) whereas those of SMX were 50.5 ± 2.3 and 55.3 ± 1.6 mg L-1, respectively. The surface properties of graphene oxide (GO) have been identified as the key effects on the adsorption of Pb(II) from aqueous solutions in this study. This study reveals the effect of the surface reactivity of GO via Carbon Disulfide (CS2) functionalization for Pb(II) adsorption. After successfully preparing CS2 functionalized GO (GOCS), the specific techniques were applied to investigate Pb(II) adsorption onto GOCS. Results indicated that the new sulfur-containing functional groups incorporated onto GOCS significantly enhanced Pb(II) adsorption capacity on GOCS than that of GO, achieving an improvement of 31% in maximum adsorption capacity increasing from 292.8 to 383.4 mg g-1. The equilibrium adsorption capacity for GOCS was 280.2 mg g-1 having an improvement of 83.2% over that of 152.97 mg g-1 for GO at the same initial concentration of 150 mg L-1 under the optimal pH of 5.7. Moreover, the results of adsorption experiments showed an excellent fit to the Langmuir and Pseudo-Second-Order models indicating the monolayer and chemical adsorption, respectively. The mechanism for Pb(II) adsorption on GOCS was proposed as the coordination, electrostatic interactions, cation-pi interactions, and Lewis acid-base interactions. The regeneration study showed that GOCS had an appreciable reusability for Pb(II) adsorption with the adsorption capacity of 208.92 mg g-1 after five regeneration cycles. In summary, GOCS has been proved to be a novel, useful, and potentially economic adsorbent for the high-efficiency removal of Pb(II) from aqueous solutions. Microplastics (MPs) pollution and its potential environmental risks have drawn increasing concerns in recent years. Among which, microbeads in personal care and cosmetic products has becoming an emerging issue for their abundance as well as the knowledge gaps in their precise environmental behaviors in freshwater. The present study investigated the sorption process of tetrabromobisphenol A (TBBPA), the most widely applied and frequently encountered flame retardant in aquatic environments, on two sources of polyethylene (PE) particles (pristine PE particles and microbeads isolated from personal care and cosmetic products). Significantly enhanced adsorption capacity of microbeads was observed with up to 5-folds higher than the pristine PE particles. The sorption efficiency was also governed by solution pH, especially for the cosmetic-derived microbeads, indicating the strong adsorption of TBBPA on PE was dominated by both hydrophobic and electrostatic interactions. Additionally, combined effects on redox status of zebrafish were evaluated with two environmental relevant concentrations of PE particles (0.5 and 5 mg L-1) using integrated biomarker response (IBR) index through a 14-d exposure. Co-exposure induced significant antioxidative stress than either PE or TBBPA alone when exposed to 0.5 mg L-1 of MPs. After 7-d depuration, the IBR value for combination treatments [TBBPA + PE (L)] was 3-fold compared with that in MP-free groups, indicating the coexistence might exert a prolonged adverse effects on aquatic organisms. These results highlight the probability of risk from microbead pollution in freshwater, where toxic compounds can be adsorbed on microbeads in a considerable amount resulting in potential adverse effects towards aquatic organisms. Microplastics (MPs), the appearance of which has gained considerable interest, can act as vectors to transport other pollutants such as metals into organisms. In this study, the sorption isotherms of three model heavy metals (i.e., Cu2+, Cd2+, and Pb2+) on four virgin plastic particles including chlorinated polyethylene (CPE), PVC, and two polyethylene plastic particles (i.e., LPE and HPE). HPE and LPE were investigated. The results showed that MPs can load high amounts of Pb2+, Cu2+ and Cd2+. The sorption affinity of the three metals to the model MPs followed the sequence of CPE > PVC > HPE > LPE. The adsorption process was affected by the chemical structure and electronegativity of the sorbents, and seemed irrelevant to the crystallinity of MPs. For the three metals, Pb2+ exhibited significantly stronger sorption than did Cu2+ and Cd2+ due to the strong electrostatic interaction. Moreover, pH can significantly affect the sorption of metals on MPs, but ionic strength exerted a relatively slight effect on this process. In brief, the electrostatic interaction played an important role in the sorption of Pb2+ to model MPs. link2 For Cd2+ and Cu2+, sorption was determined by electrostatic interaction together with surface complexation onto the plastic surface. This study indicates that depending on the surface physicochemical properties of MPs the adsorption behavior can vary significantly. Therefore, the adsorption process of metals on MPs should be readily affected by other environmental mediums in the environment. The study provides additional insight into the behavior of MPs as a vector of metals. Nitrogen-containing carbon materials (NCC-x) are promising metal-free catalysts for activation of peroxymonosulfate (PMS) to treat with aqueous organic pollutants. In this study, NCC-x were synthesized via a facile thermal polymerization method using urea and terephthalaldehyde as precursors. link3 This method was derived from the polymerization method of graphitic carbon nitride (g-C3N4) and the reaction between the precursors was based on Schiff base chemistry. Compared with the synthesis of g-C3N4 using urea as the precursor, formation of a melamine ring was inhibited and the cyano groups were produced in NCC-x during the polymerization process. The obtained NCC-x catalysts had high specific surface areas, many graphite-nitrogen active sites, and high degrees of graphitization, thus exhibiting excellent activities for the degradation of bisphenol A via PMS activation. This study introduces a convenient method to obtain a highly efficient nitrogen-containing carbon PMS activator and the results are useful for the development of bisphenol A treatment by PMS activation using carbon-containing materials. Acetamiprid is a neonicotinoid pesticide, which is extensively used on agricultural crops, but has a high toxic effect on beneficial insects and the human body. It is exposed to sunlight irradiation on crops but also in surface waters where it is found at a high level due to its resistance to common water treatments. The aim of the present work was to study the UV-visible photodegradation of acetamiprid, alone and in two marketed mixtures (Polysect Ultra SL® and Roseclear Ultra®). Ten photoproducts were characterized using LC-HR-MS/MS analysis. Photodegradation pathways were proposed based on the chemical structures of photoproducts and kinetic measurements; a matrix effect has been evidenced for commercial mixtures. Most photoproducts exhibit potential developmental toxicity twice higher than that of the parent compound. Regarding potential mutagenicity, all photoproducts are less toxic than acetamiprid. Estimated oral rat LD50 values show that the potential toxicities of photoproducts are similar or lower than that of acetamiprid.