Soil pollution has become a substantial environmental problem which is amplified by overpopulation in different regions. In this review, the state of the art regarding the use of Advanced Oxidation ...Processes (AOPs) for soil remediation is presented. This review aims to provide an outline of recent technologies developed for the decontamination of polluted soils by using AOPs. Depending on the decontamination process, these techniques have been presented in three categories: the Fenton process, sulfate radicals process, and coupled processes. The review presents the achievements of, and includes some reflections on, the status of these emerging technologies, the mechanisms, and influential factors. At the present, more investigation and development actions are still desirable to bring them to real full-scale implementation.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Air overpressure (AOp) is a hazardous effect induced by the blasting method in surface mines. Therefore, it needs to be predicted to reduce the potential risk of damage. The aim of this study is to ...offer an efficient method to predict AOp using a cascaded forward neural network (CFNN) trained by Levenberg–Marquardt (LM) algorithm, called the CFNN-LM model. Additionally, a generalized regression neural network (GRNN) and extreme learning machine (ELM) were employed to demonstrate the accuracy level of the proposed CFNN-LM model. To conduct the CFNN-LM, GRNN, and ELM models, an extensive database, related to four quarry sites in Malaysia, was used including 62 sets of dependent and independent parameters. Next, the performances of the aforementioned models were checked and discussed through statistical criteria and efficient graphical tools. Finally, the results showed the superiority of CFNN-LM (
R
2
= 0.9263 and RMSE = 3.0444) over GRNN (
R
2
= 0.7787 and RMSE = 5.1211) and ELM (
R
2
= 0.6984 and RMSE = 6.2537) models in terms of prediction accuracy. Furthermore, three different regression analysis metrics were used to perform the sensitivity analysis, and according to the obtained results, the maximum charge per delay (
β
= 0.475, SE = 0.115,
t
-test = 4.125) was considered as the most influential feature in modeling the AOp.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
A detailed investigation on photooxidation of linear alkyl benzene (LAB) industrial wastewater is presented in this study. The process analysis was performed by varying four significant independent ...variables including two numerical factors (initial pH (3–11) and initial H2O2 concentration (0–20mM)) and two categorical factors (UV irradiation and ozonation). The experiments were conducted based on a central composite design (CCD) and analyzed using response surface methodology (RSM). To assess the process performance, two parameters viz. TCOD removal efficiency and BOD5/COD were measured throughout the experiments. A maximum reduction in TCOD was 58, 53, 51, and 49%, respectively for UV/H2O2/O3, H2O2/O3, UV/O3 and UV/H2O2 processes at the optimum conditions (initial pH of 7, initial H2O2 concentration of 100mM, and reaction time of 180min). A considerable increase in BOD5/COD ratio was obtained in the combined processes (0.46, 0.51, 0.53, and 0.55 for UV/H2O2, UV/O3, H2O2/O3 and UV/H2O2/O3, respectively) compared to the single oxidant process (0.35). The results showed that mineralization of the LAB industrial wastewater in neutral pH is more favored than in acidic and basic pH. Gas chromatography–mass spectrometry (GC–MS) was applied to show the fate of organic compounds. In conclusion, the photooxidation process (UV/H2O2/O3, H2O2/O3, UV/O3 and UV/H2O2) could be an appropriate pretreatment method prior to a biological treatment process.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
An adverse outcome pathway (AOP) helps to organize existing knowledge on chemical mode of action, starting with a molecular initiating event such as receptor binding, continuing through key events, ...and ending with an adverse outcome such as reproductive impairment. AOPs can help identify knowledge gaps where more research is needed to understand the underlying mechanisms, aid in chemical hazard characterization, and guide the development of new testing approaches that use fewer or no animals. A September 2014 workshop in Bethesda, Maryland considered how the AOP concept could improve regulatory assessments of chemical toxicity. Scientists from 21 countries, representing industry, academia, regulatory agencies, and special interest groups, attended the workshop, titled Adverse Outcome Pathways: From Research to Regulation. Workshop plenary presentations were followed by breakout sessions that considered regulatory acceptance of AOPs and AOP-based tools, criteria for building confidence in an AOP for regulatory use, and requirements to build quantitative AOPs and AOP networks. Discussions during the closing session emphasized a need to increase transparent and inclusive collaboration, especially with disciplines outside of toxicology. Additionally, to increase impact, working groups should be established to systematically prioritize and develop AOPs. Multiple collaborative projects and follow-up activities resulted from the workshop.
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•AOPs provide a framework to link chemical effects on molecular initiating events, cellular changes, and adverse outcomes.•An international workshop was held in September, 2014 at the NIH on the AOP concept and regulatory toxicology.•A diverse group of scientists participated in 3 days of presentations and breakout group discussion.•Conclusions and recommendations from the breakout groups and ongoing activities and collaborations are presented.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Assessing chemical safety is essential to evaluate the potential risks of chemical exposure to human health and the environment. Traditional methods relying on animal testing are being replaced by 3R ...(reduction, refinement, and replacement) principle-based alternatives, mainly depending on
in vitro
test methods and the Adverse Outcome Pathway framework. However, these approaches often focus on the properties of the compound, missing the broader chemical-biological interaction perspective. Currently, the lack of comprehensive molecular characterization of the
in vitro
test system results in limited real-world representation and contextualization of the toxicological effect under study. Leveraging omics data strengthens the understanding of the responses of different biological systems, emphasizing holistic chemical-biological interactions when developing
in vitro
methods. Here, we discuss the relevance of meticulous test system characterization on two safety assessment relevant scenarios and how omics-based, data-driven approaches can improve the future generation of alternative methods.
•Guiding principles are outlined for the development of read-across justifications.•Scientific confidence considerations are discussed for read-across evaluation.•Aspects of these considerations are ...highlighted using 2 case studies.•These complement other frameworks in progress.
Read-across is an alternative approach exploited to address information requirements for risk assessment and for regulatory programmes such as the European Union’s REACH regulation. Whilst read-across approaches are accepted in principle, difficulties still remain in applying them consistently in practice. Recent work within Cefic LRI and ECETOC attempted to summarize the state-of-the-art and identify some of the barriers to broader acceptance of read-across approaches to overcome these. Acceptance is undoubtedly thwarted partly by the lack of a systematic framework to characterize the read-across justification and identify the uncertainties particularly for complex regulatory endpoints such as repeated-dose toxicity or prenatal developmental toxicity. Efforts are underway by the European Chemical’s Agency (ECHA) to develop a Read-Across Assessment Framework (RAAF) and private sector experts have also considered the development of a similar framework. At the same time, mechanistic chemical categories are being proposed which are underpinned by Adverse Outcome Pathways (AOPs). Currently such frameworks are only focusing on discrete organic substances, though the AOP approach could conceivably be applied to evaluate more complex substances such as mixtures. Here we summarize the deliberations of the Cefic LRI read-across team in characterizing scientific confidence in the development and evaluation of read-across.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Accurate and reliable navigation data is a key component in Internet of Things (IoT). High-precision and stable autonomous orientation has attracted considerable attention regarding environments in ...which the global navigation satellite system signal is unreliable. This study proposed a robust orientation method based on the atmospheric polarization mode called weather weighting sparse coding that includes weather classification, sparse coding, and fitting. In comparison with previous studies, the proposed method is effective in restoring the angle-of-polarization image and achieving accurate orientation under complex weather. Specifically, to achieve high-precision orientation in complex weather, a polarization compass was designed, which used the characteristics of the different levels of destruction of atmospheric polarization images under different weather conditions for classification and denoising. The proposed strategy was used to process atmospheric polarization images obtained in complex weather. Experimental results showed that the orientation accuracy was better than 0.31° (root-mean-square error) under conditions of overcast, sandstorms, clear with overexposed areas, and smog with tree-obscured and overexposed areas.
Linear polarizer-based polarimeters that measure the degree of linear polarization (DoLP) and the angle of polarization (AoP) were considered in this study. Variances of DoLP and AoP of the region of ...interest (ROI) to be measured were analyzed using a statistical method. To simplify the calculation, only additive noise and shot noise were considered. Optimized combinations of the polarizers that can minimize the variances of DoLP and AoP were determined by investigating the variances of different polarizer combinations. Several regularities were found when analyzing the data obtained from the optimized combinations. Some variables in the combinations are inversely proportional to the cube or square root of the signal-to-noise ratio of the output signals from sensors without polarizer filtering, and these variables are functions of the DoLP of the ROI to be measured.
•Noises of DoLP and AoP measured by linear polarizer-based polarimeters were modeled by a statistical strategy.•Noises of the DoLP and AoP measured by different linear polarizer angle combinations were analyzed.•The optimized combinations of linear polarizer angles that generate the smallest noise of DoLP and AoP were found.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The presence of natural organic matter (NOM) in drinking water treatment presents many challenges. Integrated treatment processes combining oxidation and biofiltration have been demonstrated to be ...very effective at reducing NOM, specifically biodegradable organics. Laboratory bench-scale experiments were carried out to investigate the effect of oxidation by ozonation or UV/H2O2 on NOM. Specifically the rate of biodegradation was studied by performing bench-scale biodegradation experiments using acclimatized biological activated carbon (BAC). For the source water investigated, oxidation did not preferentially react with the biodegradable or non-biodegradable NOM. In addition, the type or dose of oxidation applied did not affect the observed rate of biodegradation. The rate kinetics for biodegradation were constant for all oxidation conditions investigated. Oxidation prior to biofiltration increased the overall removal of organic matter, but did not affect the rate of biodegradation of NOM.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
•Acceleration between Fe2+/H2O2 and Co2+/oxone in homogeneous advanced oxidation processes has been compared.•Acceleration between Co2+/H2O2 and Fe2+/oxone in homogeneous advanced oxidation processes ...has been compared.•One mechanism step (SO5-+2H2O=3HO+SO42-+H+) is first proposed by our group in this work.
In this work, we have studied the decolouration of 0.10mM methyl orange in the presence of (1) H2O2, (2) oxone, (3) the combination of Fe2+/H2O2, (4) the combination of Co2+/oxone, (5) the combination of Co2+/H2O2, (6) the combination of Fe2+/oxone. Under the experimental conditions, the data show that H2O2 itself cannot oxidize methyl orange, oxone itself can oxidize methyl orange; all combinations can oxidize methyl orange. The acceleration sequence is: Co2+/oxone>oxone>Fe2+/oxone>Fe2+/H2O2>Co2+/H2O2>H2O2 (no effect). The roles of Fe2+ and Co2+ are catalysts, through recycling–catalysis of M2+ (M=Fe, Co) in the combination of M2+/oxidant (M=Fe, Co; oxidant=H2O2, oxone), a great quantity of HO are generated, active HO can attack methyl orange molecules and accelerate the decolouration of methyl orange. The accelerations from the combinations of oxone and different Co2+-salts (CoSO4, CoCl2, Co(NO3)2, CoAc2) are almost the same for the decolouration of the azo dye methyl orange (with one azo bond) or congo red (with two azo bonds).
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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