Physical vapor deposited (PVD) molybdenum disulfide (nominal composition MoS2) is employed as a thin film solid lubricant for extreme environments where liquid lubricants are not viable. The tribological properties of MoS2 are highly dependent on morphological attributes such as film thickness, orientation, crystallinity, film density, and stoichiometry. These structural characteristics are controlled by tuning the PVD process parameters, yet undesirable alterations in the structure often occur due to process variations between deposition runs. Nondestructive film diagnostics can enable improved yield and serve as a means of tuning a deposition process, thus enabling quality control and materials exploration. Grazing incidence X-ray diffraction (GIXRD) for MoS2 film characterization provides valuable information about film density and grain orientation (texture). However, the determination of film stoichiometry can only be indirectly inferred via GIXRD. The combination of density and microstructure via GIXRD with chemical composition via grazing incidence X-ray fluorescence (GIXRF) enables the isolation and decoupling of film density, composition, and microstructure and their ultimate impact on film layer thickness, thereby improving coating thickness predictions via X-ray fluorescence. We have augmented an existing GIXRD instrument with an additional X-ray detector for the simultaneous measurement of energy-dispersive X-ray fluorescence spectra during the GIXRD analysis. This combined GIXRD/GIXRF analysis has proven synergetic for correlating chemical composition to the structural aspects of MoS2 films provided by GIXRD. We present the usefulness of the combined diagnostic technique via exemplar MoS2 film samples and provide a discussion regarding data extraction techniques of grazing angle series measurements.

The global outbreak of coronavirus disease 2019 (COVID-19) is greatly threatening the public health in the world. We reconstructed global transmissions and potential demographic expansions of severe acute respiratory syndrome coronavirus 2 based on genomic information. We found that intercontinental transmissions were rare in January and early February but drastically increased since late February. After world-wide implements of travel restrictions, the transmission frequencies decreased to a low level in April. We identified a total of 88 potential demographic expansions over the world based on the star-radiative networks and 75 of them were found in Europe and North America. The expansion numbers peaked in March and quickly dropped since April. These findings are highly concordant with epidemic reports and modelling results and highlight the significance of quarantine validity on the global spread of COVID-19. Our analyses indicate that the travel restrictions and social distancing measures are effective in containing the spread of COVID-19.

Using an interdisciplinary model of financial planning, we investigated the factors contributing to perceived adequacy of retirement savings among Hong Kong workers by replicating a previous study of American and Dutch workers. The model was also tested for age differences in the way in which the variables operated within the model. These questions were examined using data from a phone survey conducted with 999 Hong Kong workers in 2012. We examined three psychological factors (future time orientation, goal clarity and financial knowledge), three social support variables (early learning from parents, spousal support and friend support) and three institutional factors (quality of employer pensions, trust in banks and fund managers, and trust in the government), as well as retirement savings planning activity and perceived retirement savings adequacy. Path analyses were used to test the model for the whole sample and separately for younger (N=437) and older (N=562) workers. Although a few age differences were found in the path analyses, the model was found to be useful in explaining the factors contributing to retirement savings planning and practices. Finally, we discuss how our findings differ from those of prior studies, and we assess their theoretical and practical implications.

Life expectancy has been increasing rapidly in many parts of the world, including Hong Kong. A longer life can be welcome as an opportunity to fulfil as yet unmet aspirations, or to take up new challenges and projects, but it may also be a burden, especially for individuals who are unprepared. A pressing question for longer-life societies is: how may older people live their longer lives to the full positively? This article reports a qualitative study of Hong Kong Chinese people's views about ‘positive ageing’, as expressed and discussed in 15 focus groups of middle-aged and older people. Two themes emerged: first, the participants considered that positive ageing should comprise good health, having a positive life attitude, active engagement with an activity or with society, feeling supported by their families and friends, being financially secure, and living in a place with emotional ties; and secondly, several key factors that enable positive ageing were identified, namely, adopting a healthy lifestyle, thinking positively, promoting family and inter-personal relationships, and building up financial resources. The views of the participants about ‘positive ageing’ are compared with those reported from western studies, and the policy implications are considered.

Single-crystalline, single-c-domain Pb(Zr0.52Ti0.48)O3 nanoislands (truncated-pyramid in shape) with an average height of ∼9 nm and a base length of ∼50 nm were grown on compressive niobium-doped SrTiO3(001) substrates using chemical solution deposition. Cross-sectional highresolution electron microscopy investigations allowed to propose a growth model of the islands, and they proved the existence of edge-type misfit dislocations at the interface.

We have developed two new classes of highly active and thermally stable nonlinear optical (NLO) chromophores based on the use of efficient thiophene conjugating units, a N,N-diphenylamino electron-donating group, and a 1,1′-dicyanovinyl substituted electron-accepting group. We have also developed a facile and generally applicable method to functionalize NLO chromophores onto high temperature polymers to demonstrate both high electro-optic (E-O) coefficients and long-term alignment stability at 100 °C.

The synthesis and first hyperpolarizabilities (β) of various donor-acceptor substituted thiophene containing compounds with extended conjugation are reported. Results indicate that replacing phenyl rings with less aromatic thiophene moieties enhances the second-order hyperpolarizability. Incorporating the acceptor group, N,N' diethylthiobarbituric acid, that can gain aromaticity upon charge-separation has also led to an increase in the nonlinearity. Some of the molecules have been incorporated into poIy (Methyl Methacrylate) and the electro-optic coefficients of these host-guest polymers were Measured.