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Acid gases generated during the thermal treatment of waste are neutralized using devices, such as bag filters coated with slaked lime. However, residual trace organic substances can react with the highly reactive slaked lime. This study investigates the dynamics of organic substances generated in the bag filter when slaked lime is used in the exhaust gas treatment process. The mechanism of aldehyde generation was clarified using head space gas chromatography mass spectrometer (HS-GC/MS). Results indicated that methanol was converted to formaldehyde at a conversion ratio of 0.097% and ethanol was converted to acetaldehyde at a conversion ratio of 0.260%. In addition, when amines used as emulsifiers during slaked lime production persisted in the matrix, acetaldehyde formed at a maximum concentration of 121 mg/m3. The simulation method developed in this study can be used for the initial evaluation of aldehydes unexpectedly produced in an incineration treatment facility.

We report that the thermal stability of self-assembled monolayers (SAMs) of two isocyanide derivatives (1-pentyl isocyanide and benzyl isocyanide) on a gold surface was drastically improved by their preparation at high temperature (373 K). In the case of conventionally prepared isocyanide SAMs, thermal desorption spectroscopy revealed that the isocyanides changed their adsorption states with corresponding increase in binding energy. The results of surface-enhanced Raman scattering spectroscopy measurements also clearly indicated the change in adsorption states at 373 K during heating. Theoretical calculations using density functional theory revealed that there are two stable adsorption states (atop and adatom configurations) and that the calculated vibrational energies are in good agreement with those observed in Raman spectra.

Information on the lifespan of the product is necessary to estimate the amount of its end-of-life (EOL) goods that recycling programs can expect to receive. Policymakers can set priorities for handling the EOLs, such as target collection and recovery levels, based on these estimates. In this study, we conducted a questionnaire survey to obtain information on lifespan distribution of small-size home appliances and then analyzed how this information impacts recycling system design. We found that the distribution estimates have a non-negligible level of uncertainty; accordingly, a recycling system must be designed to take this uncertainty into account.

By using the balance equation between input, output, and net addition to stock, we developed a method to estimate the lifetime distributions for buildings by statistics and some parameters from former studies. Understandable lifetime distributions were obtained from 1987 to 2010 in the type of lifetime distributions for cohort demolished in each year (D-based lifetime distribution), which was based on a hypothesis that demolition would be decided by some reasons at the time of demolition. We found that time-series change of the average lifetime depends on the economic situation, at least in the country where replacement is the dominant method of construction.

In this study, the Weibull parameters (shape parameter and mean lifetime) for lifetime distributions of electronic devices in Vietnam have been estimated based on the previous questionnaire researches by us. The mean lifetimes for four appliances were drastically decreased in seven years and lifetimes in Hanoi and Ho Chi Minh City were almost same, excluding TV. That is, the mean lifetime of TV in Hanoi and Ho Chi Minh City was found to be3.5 years and 7.6 years, respectively. The lifetimes for refrigerator, washing machine and air conditioner were estimated to be 4.2∼4.7 years, 3.9∼4.6 years and 4.7∼5.0 years, respectively.

We report light-transmittable ultrasmooth gold film enabling gap-mode tip-enhanced Raman scattering (TERS) spectroscopy measurements with extremely low background signals. An ultrasmooth Au substrate was fabricated by introducing a wetting layer of germanium (Ge). We also found that high mechanical and chemical stability of the substrate along with flexibility in chemical modification provides versatile platforms for gap-mode TERS measurements in various environments, such as air, water, and organic solvents.