Coherent array of branched filamentary scales along the wing margin of a small moth

In butterflies and moths, the wing margins are fringed with specialized scales that are typically longer than common scales. In the hindwings of some small moths, the posterior margins are fringed with particularly long filamentary scales. Despite the small size of these moth wings, these scales are much longer than those of large moths and butterflies. In the current study, photography of the tethered flight of a small moth, Phthorimaea operculella, revealed a wide array composed of a large number of long filamentary scales. This array did not become disheveled in flight, maintaining a coherent sheet-like structure during wingbeat. Examination of the morphology of individual scales revealed that each filamentary scale consists of a proximal stalk and distal branches. Moreover, not only long scales but also shorter scales of various lengths were found to coexist in each small section of the wing margin. Scale branches were ubiquitously and densely distributed within the scale array to form a mesh-like architecture similar to a nonwoven fabric. We propose that possible mechanical interactions among branched filamentary scales, mediated by these branches, may contribute to maintaining a coherent sheet-like structure of the scale array during wingbeat.     

Study on integrated management of PCB containing waste and PCB contaminated waste: proposal of new congeners for quantification

In the present study, new congeners were selected for the efficient management of PCB containing waste and PCB contaminated waste, and the applicability of these new indicators was confirmed. As a result, 8 indicator congeners and 4 index peaks which were named “Proposed new method 1” and “Proposed new method 2” were selected. For the assessment of a novel quantitative method, comparative tests using conventional methods were conducted, and the factors for total PCB were calculated for each method. Results from these tests showed that the average values for the factors of CEN/TC19/WG22, DIN 51527, and the test method by the disposal regulation for ocean dumping in Korea were 1.86, 3.47, and 2.52, respectively, while those for the proposed new method 1 and proposed new method 2 were 2.98 and 5.56, respectively. For PCB contaminated waste, the factor was found to be 1.99, 3.42, and 3.02 using the conventional methods, 2.67 using the proposed new method 1, and 5.57 using the proposed new method 2. It is expected that, in accordance with the results of the present study, the management of PCB waste can be integrated, regardless of the type of waste involved.     

Comprehensive modeling of HFC-23 incineration in a CDM incinerator

Considering that a significant part of used refrigerants have to be destroyed in an environmentally friendly manner together with the high global warming potential (GWP) of HFCs (hydrofluorocarbons), the development of a proper incineration method of HFCs becomes one of the viable methods in the refrigeration and air-conditioning industry. To this end, in this study, the development of a comprehensive modeling of CHF₃ (HFC-23 or R-23) incineration is made to assist in the proper design and determination of optimal operating condition of a practical HFCs incinerator, since the refrigerant of CHF₃ is one of typical HFCs. For this, numerical investigation was performed by the development of a predictive model for the thermal destruction of the CHF₃ using CH₄–air flames in an incinerator designed for CDM (clean development mechanism) project. First of all, comparison between calculation and operation data was made to evaluate the program developed in this study. Numerical calculation of CHF₃–CH₄–air flame predicts successfully the operation data of a CDM incinerator such as temperature, CHF₃ destruction rate more than 99.99 % and other species concentrations such as CO and NO at the exit of the incinerator. Further parametric study was performed also in terms of important variables such as excess air, amount of steam and incinerator size. In general, the results obtained appear physically acceptable and give a clear physical insight into the role of the important variables. Further work is strongly recommended for the development of a general turbulent reaction model for the thermal destruction of HFCs, especially for the condition of non-equilibrium turbulent reaction dominance.     

An international comparative study of end-of-life vehicle (ELV) recycling systems

End-of-life vehicles (ELV) have become a global concern as automobiles have become popular worldwide. An international workshop was held to gather data and to discuss 3R policies and ELV recycling systems, their background and present situation, outcomes of related policies and programs, the framework of recycling and waste management, and case studies on related topics in several countries and regions, as well as the essential points of the comparison. Legislative ELV recycling systems are established in the EU, Japan, Korea, and China, while in the US, ELV recycling is managed under existing laws on environmental protection. Since automobile shredding residue (ASR) has a high calorific value and ash content, and includes heavy metals as well as a mass of unclassified fine particles, recycling ASR is considered highly difficult. Countries with a legislative ELV system commonly set a target for recovery rates, with many aiming for more than 95 % recovery. In order to reach this target, higher efficiency in ASR recovery is needed, in addition to material recycling of collectable components and metals. Environmentally friendly design was considered necessary at the planning and manufacturing stages, and the development of recycling systems and techniques in line with these changes are required for sound ELV management.     

Butyltin residues in blue mussels (Mytilus edulis) and arkshells (Scapharca broughtonii) collected from Korean coastal waters

Butyltin compounds (BTs) including tributyltin (TBT) and its degradation products, di- (DBT) and mono-butyltin (MBT), were determined in bivalves such as blue mussels (Mytilus edulis) and arkshells (Scapharca broughtonii) collected from Korean coastal waters. BTs were detected in all the blue mussels and arkshells analyzed. The concentrations of total butyltin (sigmaBTs: MBT + DBT + TBT) in blue mussels and arkshells ranged from 49 to 2500 ng/g and 29 to 87 ng/g wet weight, respectively. Higher concentrations of BTs were found in blue mussels collected from Okpo and Kohyonsong Bays and Jangsengpo Harbor where large shipyards and harbors are located with dry-dock facilities. This suggested that maritime activities nearby the harbors play a major role as the source of BTs. Concentrations of TBT in mussels collected from Korea were one of the highest values reported, suggesting ongoing TBT contamination in Korea. Among BTs, TBT was the predominant compound both in blue mussels and arkshells collected from almost all the sampling locations, indicating the fresh input of TBT in Korean coastal waters. Smaller mussels tended to accumulate BTs at higher concentrations than larger ones, which may be due to higher filtration rate of small mussels and/or contact with surface microlayer in intertidal zones.     

Precipitation of swine and cattle manure phosphorous using limestone dust

The effectiveness of SPS and PULPRO, fine limestone dusts, in precipitating swine and dairy manure phosphorous (P) was determined in the laboratory. Both manures were sieved before being treated with limestone, to reproduce the treatment of mechanically separated manure and to observe the precipitation effect of limestone without that of the large manure solid particles. P precipitation was optimized by varying precipitation conditions (propeller blade speeds, mixing time and limestone levels) and limestone particle size. P precipitation was optimized using a propeller blade mixing speed of 0.3 m s(-1) for at least 5 minutes, using 3% limestone (dry limestone mass over wet manure mass). In terms of particle size, PULPRO 20 (limestone with a particle size of 0.02 mm) produced the most P precipitation and the smallest volume and mass of sludge, as compared to PULPRO 10, PULPRO 3 and SPS (limestone with a particle size of 0.01, 0.003 and 0.3 to 0.003 mm, respectively). For both 9.5% TS (total solids) dairy and 8.8% TS swine manure, mechanical separation followed by limestone precipitation concentrated 90% of manure TS and TP in a sludge volume representing 45% of the initial raw manure mass.     

Cadmium ion sorption onto lignocellulosic biosorbent modified by sulfonation: the origin of sorption capacity improvement

Juniper (Juniperus monosperma), a small-diameter underutilized material, has been studied as a lignocellulosic biosorbent for removing heavy metals from water. In this study, juniper wood was modified by sulfonation to enhance sorption capacity for cadmium in water. The origin of the enhancement was investigated by observing the sorption behaviors and the change in surface functional group concentrations. Cadmium sorption by all juniper wood biosorbents studied was fast and the sorption capacity decreased with decreasing pH, similar to results found for other biosorbents. Sulfonated juniper was found to have at least twice the sorption capacity for cadmium removal from water compared to that of untreated juniper, though the sorption capacity increased with increasing pH. A slight increase in carboxylate content after sulfonation was likely responsible for a small portion of the enhancement. Elemental analysis showed an increase in sulfur content after sulfonation. Diffuse reflectance infrared Fourier transform (DRIFT) spectra showed a decrease in the band at 1660 cm(-1) in the range of carbonyl groups as a result of sulfonation. This indicates that coniferaldehyde groups in the lignin of juniper wood corresponding to this band were substituted into sulfonic acid groups after sulfonation. This interpretation was supported by both the color forming reaction with phloroglucinol-hydrochloric acid and the reaction mechanisms from the acid sulfite pulping process. Consequently, the enhancement of cadmium sorption capacity of juniper wood by sulfonation mainly originated from the production of sulfonic acid groups, which are binding sites for heavy metals.