Development of intelligent sorting system realized with the aid of laser-induced breakdown spectroscopy and hybrid preprocessing algorithm-based radial basis function neural networks for recycling black plastic wastes

Plastic recycling has been the key issue for reducing environmental problems and resolving resource depletion. To improve the recovery rate of plastics, the plastic wastes are correctly identified according to their resin type. However, the identification system, which is able to identify black plastics according to not only the type of black plastics but also the grade of resins correctly, has not been introduced. In this paper, laser-induced breakdown spectroscopy, intelligent algorithms and preprocessing algorithms are used to improve the identification of black plastics such as polypropylene, polystyrene (PS), and acrylonitrile butadiene styrene (ABS). The laser-induced breakdown spectroscopy is capable of obtaining the characteristic spectrum regardless of material’s physical state. To extract the new features which are very valuable to improving learning performance, increasing computational efficiency, and building better generalization models from the obtained spectra through laser-induced breakdown spectroscopy, the hybrid preprocessing algorithm, composed of principal component analysis and independent component analysis, is used. In addition, the intelligent algorithm named the extended radial basis function neural networks inheriting the advantages of fuzzy theory and neural networks is used to identify black plastic samples into several categories with respect to their resins. The proposed identification system, composed of three parts such as laser induced breakdown spectroscopy, hybrid preprocessing algorithms, and an efficient intelligent classification algorithm, is able to show the synergy effect on the black plastic identification problem. From several experimental results, it can be seen that the identification system based on laser-induced breakdown spectroscopy and the intelligent algorithm is used for identification of black plastics by resin type.     

Isolation and identification of potential fungal species for spent engine lubrication oil remediation in Peninsular Malaysia

Improper disposal and spills of spent engine oil into the environment can result in contamination, which eventually affects humans through the food chain. Mycoremediation is an effective and inexpensive alternative to clean up spent engine oil contamination. In recent work, the potential effectiveness of fungi for degrading spent engine oil was confirmed, with the species identified through molecular identification. Fungi that were able to grow in Bushnell Haas Broth supplied with spent engine oil were identified with the potential to utilize spent engine oil as a carbon source. Six species of fungi namely Penicillium simplicissimum, Aspergillus nidulans, Aspergillus niger, Trichoderma longibrachiatum, Aspergillus ustus, and Aspergillus flavus were successfully identified in this study. Over a course of seven days, P. simplicissimum (21.11 percent) was identified as the most effective fungi in degrading spent engine oil, followed by A. nidulans (17.75 percent), A. niger (15.85 percent), T. longibrachiatum (15.12 percent), A. ustus (15.02 percent), and A. flavus (11.80 percent). As these species of fungi were isolated from the natural environment in Peninsular Malaysia, the potential of using these fungi as mycoremediation of spent engine oil was therefore confirmed.     

A meta‐analysis of the antecedents of work–family enrichment

This study meta‐analytically examined theoretically derived antecedents of both directions of work–family enrichment (sometimes labeled facilitation or positive spillover), namely, work–family enrichment and family–work enrichment. Contextual and personal characteristics specific to each domain were examined. Resource‐providing (e.g., social support and work autonomy) and resource‐depleting (e.g., role overload) contextual characteristics were considered. Domain‐specific personal characteristics included the individuals' psychological involvement in each domain, the centrality of each domain, and work engagement. Results based on 767 correlations from 171 independent studies published between 1990 and 2016 indicate that several contextual and personal characteristics have significant relationships with enrichment. Although those associated with work tend to have stronger relationships with work–family enrichment and those associated with family tend to have stronger relationships with family–work enrichment, several antecedent variables have significant relationships with both directions of enrichment. Resource‐providing contextual characteristics tend to have stronger relationships with enrichment than do resource‐depleting characteristics. There was very little evidence of gender being a moderator of relationships between contextual characteristics and enrichment. Lastly, meta‐analytic structural equation modeling provided evidence that a theoretical path model wherein work engagement mediates between several contextual characteristics and enrichment is largely generalizable across populations.     

Effects of carbon nanotube and biochar on bioavailability of Pb,Cu and Sb in multi-metal contaminated soil

This study examined the effects of carbon nanotube and biochar on the bioavailability of Pb, Cu and Sb in the shooting range soils for developing low-cost remediation technology. Commercially available multi-walled carbon nanotube (MWCNT) and biochar pyrolyzed from soybean stover at 300 °C (BC) at 0.5, 1 and 2.5% (w w^?1) were used to remediate the contaminated soil in an incubation experiment. Both DTPA (bioavailable) and TCLP (leaching) extraction procedures were used to compare the metal/loid availability and leaching by the amendments in soil. The addition of BC was more effective in immobilizing mobile Pb and Cu in the soil than that in MWCNT. The BC reduced the concentrations of Pb and Cu in the soil by 17.6 and 16.2%, respectively. However, both MWCNTs and BC increased Sb bioavailability by 1.4-fold and 1.6-fold, respectively, in DTPA extraction, compared to the control. The toxicity characteristic leaching procedure (TCLP) test showed that the leachability of Pb in the soil amended with 2.5% MWCNT was 1.3-fold higher than that the unamended soil, whereas the BC at 2.5% decreased the TCLP-extractable Pb by 19.2%. Precipitation and adsorption via electrostatic and π–π electron donor–acceptor interactions were postulated to be involved in the interactions of Pb and Cu with surfaces of the BC in the amended soils, whereas ion exchange mechanisms might be involved in the immobilization of Cu in the MWCNT-amended soils. The application of BC derived from soybean stover can be a low-cost technology for simultaneously immobilizing bioavailable Pb and Cu in the shooting range soils; however, neither of amendments was effective in Sb immobilization.     

The influences of recycle effect on double-pass V-corrugated solar air heaters

The study of the heat transfer enhancement for the recycling double-pass V-corrugated solar air heaters, which implement the external recycle of flowing air, was investigated experimentally and theoretically. The comparison among different designs of V-corrugated, baffled and fins attached, and flat-plate collectors was made to show the device performance improvement with various operating parameters under the same working dimensions. The recycling double-pass V-corrugated device developed here was proposed in aiming to strengthen the convective heat-transfer coefficient and enlarge the heat transfer area. The error analysis of experimental results deviate by 0.85–2.46% from the theoretical predictions with the fairly good agreement, and both results show that the device performance of the recycling double-pass V-corrugated operation is better than those of the other configurations under various recycle ratios and mass flow rates. The suitable selections were obtained for operating recycling double-pass V-corrugated devices while considering with an economic viewpoint by both the collector efficiency enhancement and the power consumption increment.     

Comparative study of torrefaction of empty fruit bunches and palm kernel shell

Journal of Material Cycles and Waste Management - This paper describes the effect of torrefaction on the characteristics of empty fruit bunches (EFB) and palm kernel shell (PKS). The torrefaction...     

低pH、铝及钙铝比对斜生栅藻(Scenedesmus obliquus)的生理生化影响

为探讨酸沉降对生物早期伤害的机理,研究不同ＰＨ条件下,铝及钙／铝比对斜生栅藻与磷和氮营养代谢有关酶活性的影响,结果表明,铝对酸性磷酶和硝酸还原酶活性有显著抑制作用,当ＰＨ为６．８和５．２,铝２为０．７ｍｇ／Ｌ时,酸性磷酸酶活性仅分别为对照组的４６％和５６％,而硝酸还原酶活性仅为对照组的３７％和３０％当培养基中适当量的钙离子,会一定程度保护藻细胞中这２个酶活性不受低ＰＨ及铝的伤害,钙的缓解作用取决于     

Sustainable Water Resources Management in a Conflict Resolution Framework1

Abstract: A decision support system for sustainable water resources management in a water conflict resolution framework is developed to identify and evaluate a range of acceptable alternatives for the Geum River Basin in Korea and to facilitate strategies that will result in sustainable water resource management. Working with stakeholders in a “shared vision modeling” framework, sustainable management strategies are created to illustrate system tradeoffs as well as long‐term system planning. A multi‐criterion decision‐making (MCDM) approach using subjective scales is utilized to evaluate the complex water resource allocation and management tradeoffs between stakeholders and system objectives. The procedures used in this study include the development of a “shared vision model,” a simulated decision‐making support system (as a tool for sustainable water management strategies associated with water conflicts, management options, and planning criteria), and the application of MCDM techniques for evaluating alternatives provided by the model. The research results demonstrate the utility of the sustainable water resource management model in aid of MCDM techniques in facilitating flexibility during initial stages of alternative identification and evaluation in a basin suffering from severe water conflicts.     

Analysis of gas flow behavior in an annular fluidized-bed reactor for polystyrene waste treatment

The characteristics of bubble properties and the chaotic flow behavior of gas were investigated in an annular fluidized bed (0.102 m in inner diameter and 2 m in height) because the behavior of gas flow in such a reactor is one of the important factors governing reactor operation, reactor performance, and the reaction itself. Pressure fluctuations as a state variable for the analysis of gas flow behavior were measured and analyzed. Bubble properties were determined by adopting the cross-correlation function of pressure fluctuations. The resultant chaotic flow behavior of gas was interpreted by means of chaotic parameters such as the Kolmogorov entropy. It was found that the Kolmogorov entropy could be utilized effectively to explain the nonlinear dynamic behavior of gas-solid flow in the annular fluidized bed. The pierced length and rising velocity of bubbles increased with increasing gas velocity, bed temperature, and particle size of the bed material. The bubble frequency increased with increasing gas velocity and bed temperature, while it decreased with increasing particle size of the bed material. Correlations to predict the bubble properties in annular fluidized-bed reactors were suggested.     

A feasibility study of thermal hydrolysis by-products as barrier layer materials in the final cover system for a landfill

Most sludge has historically been disposed of in landfills and by ocean dumping but, because of its heavy metal content, this will be totally banned in Korea starting in 2012, based on the London Dumping Convention. Therefore, treatment and disposal methods that are environmentally friendlily are urgently required. The recycling of sewage sludge is a good treatment method for solving sludge problems in an environmentally friendly way. In this study, physical and environmental tests were conducted to evaluate the feasibility of using the by-products of thermal hydrolysis of sewage sludge as barrier layer materials in the final cover systems for landfills. In addition, testing methods for freezing-thawing (KS F 2332) and wetting-drying (KS F 2330) cycles were conducted to assess the effects of cold and hot soil climates starting from pavement. These tests yielded positive results for alternative materials for the barrier layer in a final cover system for a landfill.