Publications by authors named "R P Kwok"

Using methods of DFT, we investigated the effect of electron withdrawing and electron donating groups on the relative stability of tentative glycosyl donor reaction intermediates. The calculation shows that by changing the stereoelectronic properties of the protecting group, we can influence the stability of the dioxolenium type of intermediates by up to 10 kcal mol, and that by increasing nucleophillicity of the 4--Bz group, the dioxolenium intermediate becomes more stable than a triflate-donor pair. We exploited this mechanism to design galactosyl donors with custom protecting groups on O2 and O4, and investigated the outcome of the reaction with cyclohexanol.

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Photosensitizers (PSs) featuring type I reactive oxygen species (ROS) generation and aggregation-induced emission (AIE) activity offer a promising solution to achieve non-invasive and precise theranostics. However, the reported AIE luminogens (AIEgens) with both AIE characteristic and strong type-I ROS generation are still scarce and the structure-property relationship is still unclear. Herein, an innovative acceptor elongation boosted intersystem crossing (AEBIC) design strategy has been proposed to endow the AIEgen strong type-I ROS producibility.

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The mental health of asylum seekers and refugees (ASRs) is a pressing global concern, with complex trauma histories and environmental stressors contributing to heightened vulnerability. This study investigates the mental health and service utilization patterns of ASRs in Hong Kong, where unique policy landscapes pose additional challenges to this population. A cross-sectional survey was conducted with 100 ASRs in Hong Kong.

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Fe-N-C materials are emerging catalysts for replacing precious platinum in the oxygen reduction reaction (ORR) for renewable energy conversion. However, their potential is hindered by sluggish ORR kinetics, leading to a high overpotential and impeding efficient energy conversion. Using iron phthalocyanine (FePc) as a model catalyst, we elucidate how the local strain can enhance the ORR performance of Fe-N-Cs.

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The two contradictory entities in nature often follow the principle of unity of opposites, leading to optimal overall performance. Particularly, aggregation-induced emission luminogens (AIEgens) with donor-acceptor (D-A) structures exhibit tunable optical properties and versatile functionalities, offering significant potential to revolutionize cancer treatment. However, trapped by low molar absorptivity (ε) owing to the distorted configurations, the ceilings of their photon-harvesting capability and the corresponding phototheranostic performance still fall short.

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