A new method has been proposed to estimate top heat losses of vertical flat plate liquid/air collectors with double glazing. Empirical relations have been developed for the temperatures of glass covers, thus facilitating the calculation of individual heat transfer coefficients. The values of individual heat transfer coefficients therefore obtained can be used in the proposed analytical equation for the estimation of the top heat loss coefficient of the vertical collector with double glazing. The analytical equation has been developed for collector tilt angle of 60 to 90 degrees, plate temperature of 323 K to 423 K, absorber coating emittance of 0.1 to 0.95, air gap spacing of 20 mm to 50mm between the plate and inner glass cover, air gap spacing of 20 mm to 50mm between glass covers, wind heat transfer coefficient of 5 W/m2K to 30 W/m2K, and ambient temperature of 263K to 313K. The accuracy of the analytical equation has been validated for the said range of variables in comparison to numerical solutions, and the values of the top heat loss coefficient are found to be within 2.5 percent compared to numerical solutions.
COVID-19 has led to abrupt changes in work norms and practices. Despite receding pandemic restrictions, the popularity of remote or hybrid work has not subsided. As employees around the world continue to call for more flexibility and autonomy in the way they work, human resource leaders must continuously consider and evaluate decisions based on ever-changing sentiment, balancing the interests of employees and employers alike. In this perspective article, we review the current state of work in the Southeast Asian region, focusing on Malaysia, Singapore, Indonesia, the Philippines, and Thailand, and present preliminary results from a region-wide mental health assessment that was conducted in late 2022. We argue for the continuation of hybrid work in the region and elaborate on the mental health risks that come with remote working.
This article aims to elucidate governance primarily from the perspective of collaboration and leadership in managing disasters. This article studies the case of Indonesia, a country with frequent and complex nature of disasters, located on the Pacific Ring of Fire to analyze its disaster management system and draw out implications from its experience. The method used is a qualitative comprehensive and systematic review from national and international earthquake occurrences. The finding is that Indonesia is simultaneously carrying out disaster management which is not contradictory but complementary. The importance of collaboration is imposed and recommendations are offered on rectifying collaborative activities’ value. Modern leadership strategies suggest that acquire their power from effective strategies and transformational power rather than standard operating procedures. This paper provides lessons on how to organize earthquake management through aspects of collaboration and leadership effectively. The author suggests optimizing the potential of the community by providing special assistance to increase disaster management efforts.
In this paper, spherical gold nanoparticles (AuNPs), rod-shape AuNPs and triangular AuNPs were synthesized using CTAB as the coating reagent, and their bactericidal properties against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) were studied. By the plate count method and turbidity method, the minimum bactericidal concentrations (MBC) and the minimum bacteriostasis concentrations (MIC) to the two kinds of bacteria were determined. The MIC of rod-shape AuNPs, triangular AuNPs and spherical AuNPs to E. coli were 0.65 μg/mL, 3.71 μg/mL, 21.21 μg/mL, and MBC were 1.30 μg/mL, 11.09 μg/mL, 21.21 μg/mL, respectively. The MIC to S. aureus were 0.26 μg/mL, 0.56 μg/mL, 2.65 μg/mL, while MBC were 0.52 μg/mL, 1.11 μg/mL, 2.65 μg/mL, respectively. The results showed that the bactericidal effect of rod-shape AuNPs on E. coli and S. aureus was higher than that of the other two forms, and the bactericidal effect of three different forms of AuNPs on S. aureus was better than that on E. coli.
Public-Private Partnerships (PPPs) can be an effective way of delivering infrastructure. However, achieving value for money can be difficult if government agencies are not equipped to manage them effectively. Experience from OECD countries shows that the availability of finance is not the main obstacle in delivering infrastructure. Governance—effective decision-making—is the most influential aspect on the quality of an investment, including PPP investments. In 2012, the OECD together with its member countries developed principles to ensure that PPPs deliver value for money transparently and prudently, supported by the right institutional capacities and processes to harness the upside of PPPs without jeopardizing fiscal sustainability. Survey results from OECD countries show that some dimensions of the recommended practices are well applied and past and ongoing reforms show progress. However, other principles have not been well implemented, reflecting the continuing need for improving public governance of PPPs across countries.
The silver nanoparticles (AgNPs) exhibit unique and tunable plasmonic properties. The size and shape of these particles can manipulate their localized surface plasmon resonance (LSPR) property and their response to the local environment. The LSPR property of nanoparticles is exploited by their optical, chemical, and biological sensing. This is an interdisciplinary area that involves chemistry, biology, and materials science. In this paper, a polymer system is used with the optimization technique of blending two polymers. The two polymer composites polystyrene/poly (4-vinylpyridine) (PS/P4VP) (50:50) and (75:25) were used as found suitable by their previous morphological studies. The results of 50, 95, and 50, 150 nm thicknesses of silver nanoparticles deposited on PS/P4VP (50:50) and (75:25) were explored to observe their optical sensitivity. The nature of the polymer composite embedded with silver nanoparticles affects the size of the nanoparticle and its distribution in the matrix. The polymer composites used are found to have a uniform distribution of nanoparticles of various sizes. The optical properties of Ag nanoparticles embedded in suitable polymer composites for the development of the latest plasmonic applications, owing to their unique properties, were explored. The sensing capability of a particular polymer composite is found to depend on the size of the nanoparticle embedded in it. The optimum result has been found for silver nanoparticles of 150 nm thickness deposited on PS/P4VP (75:25).
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