Recent Progress in Plasmonic Hybrid Photocatalysis for CO2 Photoreduction and C-C Coupling Reactions

Plasmonic hybrid nanostructures have been investigated as attractive heterogeneous photocatalysts that can utilize sunlight to produce valuable chemicals. In particular, the efficient photoconversion of CO2 into a stable hydrocarbon with sunlight can be a promising strategy to achieve a sustainable human life on Earth. The next step for hydrocarbons once obtained from CO2 is the carbon-carbon coupling reactions to produce a valuable chemical for energy storage or fine chemicals. For these purposes, plasmonic nanomaterials have been widely investigated as a visible-light-induced photocatalyst to achieve increased efficiency of photochemical reactions with sunlight. In this review, we discuss recent achievements involving plasmonic hybrid photocatalysts that have been investigated for CO and CO2 photoreductions to form multi-carbon products and for C-C coupling reactions, such as the Suzuki-Miyaura coupling reactions

Prevalence of Allergic Diseases among Korean School-age Children: A Nationwide Cross-Sectional Questionnaire Study

The purpose of this study was to investigate the nationwide prevalence of childhood asthma, eczema and other allergic diseases in Korean school-age children (8-11 yr old) and to assess the difference between residential areas. Among 6,279 elementary schools, 427 schools were randomly selected according to residential area (metropolitan, provincial, rural, and industrial area) by the cluster sampling method. Parents of students completed a modified Korean version of a questionnaire formulated by the International Study of Asthma and Allergies in Childhood (ISAAC). Among 50,200 subjects, 31,026 (61.8%) responded, and 30,893 (99.6%) were analyzed. The 12-month prevalence of wheeze, flexural rash, and allergic rhinitis symptoms were 4.8%, 15.3%, and 32.9%, respectively. The prevalence of diagnosis of allergic diseases in boys was higher than that in girls, with the exception of eczema. In both boys and girls, the difference of the prevalence of allergic diseases among industrial, metropolitan and provincial areas was not statistically significant, but the differences between rural area and other areas were significant. Our results support the importance of contextual effect associated with residential area as causative agents of allergic diseases among Korean school-age children

Molecular Structure of Selected Tuber and Root Starches and Effect of Amylopectin Structure on Their Physical Properties

The objectives of this study were to characterize starches isolated from potato, canna, fern, and kudzu, grown in Hangzhou, China, for potential food and nonfood applications and to gain understandings of the structures and properties of tuber and root starches. Potato and canna starches with B-type X-ray patterns had larger proportions of amylopectin (AP) long branch chains (DP g37) than did fern (C-type) and kudzu (CA-type) starches. The analysis of Naegeli dextrins suggested that fern and kudzu starches had more branch points, R-(1,6)-D-glycosidic linkages, located within the double-helical crystalline lamella than did the B-type starches. Dispersed molecular densities of the C- and CA-type APs (11.6-13.5 g/mol/nm3) were significantly larger than those of the B-type APs (1.4-6.1 g/mol/nm3) in dilute solutions. The larger proportion of the long AP branch chains in the B-type starch granules resulted in greater gelatinization enthalpy changes (ΔH). Retrograded kudzu starch, which had the shortest average chain length (DP 25.1), melted at a lower temperature (37.9 °C) than the others. Higher peak viscosities (550-749 RVU at 8%, dsb) of potato starches were attributed to the greater concentrations of phosphate monoesters, longer branch chains, and larger granule sizes compared with other tuber and root starches

Performance Comparison of Spectral Wave Models Based on Different Governing Equations Including Wave Breaking

The performance of three spectral wave models based on different types of governing equations, REF/DIF S, MIKE 21 BW module and SWAN, was compared by using four laboratory and field experimental data. The comparison was focused on accurate prediction of the measured wave height. Characteristics of the three wave models were discussed and their overall predictability of the measured data was evaluated by calculating mean absolute relative errors of wave height. All the numerical models simulated fairly well shoaling and breaking of waves propagating on a plane sloping beach, but the model accuracy was somewhat degenerated in simulating waves propagating over a barred beach. Among the three models, MIKE 21 BW was the most insensitive to the bathymetric change. Combined refraction-diffraction over a shoal without breaking was quite well simulated by the models, especially by REF/DIF S and MIKE 21 BW. When waves break over the shoal, however, all the models failed to reproduce the wave field behind the shoal. The agreement with data in simulating wave diffraction around breakwater was remarkably good for MIKE 21 BW, but very poor for other two models. Except the last simulation, the mean absolute relative errors of wave height from the three models ranged between 3 and 27%