Broken crayon

A 6 year old girl, Ah girl, lives with her four year old sister, Ah Mei and her healthy grandparents in a 4 room HDB flat. Her grandmother tends to be nonchalant and has a mindset of minding one's own business. Her grandmother loves to take afternoon naps and likes watching TV. On the other hand, her grandfather loves watching porn in her uncle’s room. The chauvinistic grandfather brings Ah Girl's male cousin Ah Wah, who is only 2 years older than her into the uncle’s room to watch pornography films together during his weekend stay with the grandparents. On that day itself, Ah Wah performs what he saw on Ah girl. Ah Wah’s mother and grandparents are aware of the situation but yet they chose not to control it, which leads to many undesirable consequences...Bachelor of Fine Art

Graphite oxide- and graphene oxide-supported catalysts for microwave-assisted glucose isomerisation in water

Graphite (G), graphite oxide (GIO), and graphene oxide (GO) were evaluated for the first time as carbonaceous supports to synthesise heterogeneous Lewis acid catalysts, via simple AlCl3 pretreatment followed by one-step thermal modification. The GIO- and GO-supported Al catalysts were active towards catalytic isomerisation of glucose in water as the greenest solvent. The highest fructose yield of 34.6 mol% was achieved under microwave heating at 140 °C for 20 min. The major active sites were characterised as amorphous Al hydroxides (e.g., β-Al(OH)3, γ-Al(OH)3, and γ-AlO(OH)) with octahedral coordination, as revealed by 27Al NMR, XPS, SEM, TEM-EDX, Raman, ESR, and XRD analyses. The transformation of octahedral Al to pentahedral/tetrahedral coordination was observed when the activation temperature increased. Oxygen-containing functional groups on the GIO and GO surfaces, e.g., C-O-C, -OH, and -COOH, contributed to the formation of microwave-absorbing active sites. In contrast, the G-supported catalyst may contain microwave-transparent Al hydroxides, accounting for its low catalytic activity under microwave irradiation. This study elucidates the significance of the surface chemistry of carbonaceous supports in generating active species for a Lewis acid-driven reaction. The revealed intertwined relationships among modification conditions, physicochemical properties, and catalytic performance will be useful for designing effective carbon-supported catalysts for sustainable biorefinery

Microplastics as Pollutants in Agricultural Soils

Microplastics (MPs) as emerging persistent pollutants have been a growing global concern. Although MPs are extensively studied in aquatic systems, their presence and fate in agricultural systems are not fully understood. In the agricultural soils, major causes of MPs pollution include application of biosolids and compost, wastewater irrigation, mulching film, polymer-based fertilizers and pesticides, and atmospheric deposition. The fate and dispersion of MPs in the soil environment are mainly associated with the soil characteristics, cultivation practices, and diversity of soil biota. Although there is emerging pollution of MPs in the soil environment, no standardized detection and quantification techniques are available. This study comprehensively reviews the sources, fate, and dispersion of MPs in the soil environment, discusses the interactions and effects of MPs on soil biota, and highlights the recent advancements in detection and quantification methods of MPs. The prospects for future research include biomagnification potency, cytotoxic effects on human/animals, nonlinear behavior in the soil environment, standardized analytical methods, best management practices, and global policies in the agricultural industry for the sake of sustainable development

Study of glucose isomerisation to fructose over three heterogeneous carbon-based aluminium-impregnated catalysts

Driven by the worldwide demand for sustainable resources and renewable energy, the synthesis of bio-based platform chemicals has attracted broad interest. The isomerisation of glucose to fructose acts as a critical intermediate step among many chemical synthesis routes. In this study, biochar (BC), graphitic oxide (GIO), and graphene oxide (GO) were used as carbon supports to synthesize Al-impregnated heterogeneous catalysts, which were then used for glucose isomerisation under microwave heating in the water at 140 °C. The kinetics model with parameters was used to reveal the interplay of the active sites and compare the activity of the three carbon-based catalysis systems. Catalyst characterisation results showed effective aluminium (Al) impregnation onto the three types of catalysts, and it was found that GIO-Al200 and GO-Al200 showed comparable catalytic activity (fructose yield of 34.3–35.0%) for glucose isomerisation. At the same time, BC-Al200 exhibited slightly lower catalytic activity (fructose yield of 29.4%). The conversion kinetics suggested similar catalytic mechanisms on the three catalysts while BC-Al200 manifested slower kinetics, possibly implying higher activation energy. The fructose selectivity decreased with increasing time due to the formation of side products, yet BC-Al200 resulted in less carbon loss than GIO-Al200 and GO-Al200, probably attributed to its lower catalytic activity and higher pH buffering capacity. A green synthesis route of this study promotes biomass valorisation and makes engineered biochar a promising carbon-based catalyst for sustainable biorefinery

Biorenewable hydrogen production through biomass gasification : A review and future prospects

Hydrogen is recognized as one of the cleanest energy carriers, which can be produced from renewable biomass as a promising feedstock to achieve sustainable bioeconomy. Thermochemical technologies (e.g., gasification and pyrolysis) are the main routes for hydrogen production from biomass. Although biomass gasification, including steam gasification and supercritical water gasification, shows a high potential in field-scale applications, the selectivity and efficiency of hydrogen production need improvement to secure cost-effective industrial applications with high atom economy. This article reviews the two main-stream biomass-to-hydrogen technologies and discusses the significance of operating conditions and considerations in the catalytic system design. Challenges and prospects of hydrogen production via biomass gasification are explored to advise on the critical information gaps that require future investigations