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This study assessed thermal comfort and energy consumption in indoor environments controlled by air or operative temperature. Reading rooms in a library were divided into several zones based on the distribution of operative temperature. Using air temperature of the inner zone in thermostat control yielded the lowest energy consumption but the poorest thermal comfort level. Conversely, using operative temperature of the least favorable exterior zone resulted in higher energy consumption and comfort levels. The suggested optimal control based on switching boundary temperature minimized energy consumption while satisfying the thermal comfort requirement. The switching boundary temperature range on the top floor is 0.7 °C lower than on the middle floor due to the influence of the roof. The thermostat control modes had similar effects on the east and west reading rooms. The switching boundary temperature ranges of north room was 2.0 °C higher than those of the south room. Zoning control using air temperature control in the inner zone and operative temperature control in the exterior zone was recommended as a much simple mode to keep thermal comfort with low energy use. This study provides insights about the use of operative temperature in zoning thermostat control and theoretical guidance for practical implementation. • Control modes based on air/operative temperature of different zones were proposed. • Thermal comfort of reading rooms is ensured when operative temperature control is used. • Switching boundary temperature range is defined and optimized control is recommended. • Optimized control ensures thermal comfort with the lowest increment in energy use. [ABSTRACT FROM AUTHOR]

As the "kidneys of the Earth", wetlands play important roles as biodiversity reservoirs, in water purification, and in flood control. In this study, 2 lytic cold-active bacteriophages, named VW-6S and VW-6B, infecting Pseudomonas fluorescens W-6 cells from the Napahai plateau wetland in China were isolated and characterized. Electron microscopy showed that both VW-6S and VW-6B had an icosahedral head (66.7 and 61.1 nm, respectively) and a long tail (8.3 nm width x 233.3 nm length and 11.1 nm width x 166.7 nm length, respectively). The bacteriophages VW-6S and VW-6B were classified as Siphoviridae and had an approximate genome size of 30-40 kb. The latent and burst periods of VW-6S were 60 and 30 min, whereas those of VW-6B were 30 and 30 min, respectively. The optimal pH values for the bacteriophages VW-6S and VW-6B were 8.0 and 10.0, respectively, and their activity decreased rapidly at temperatures higher than 60 °C. These cold-active bacteriophages provide good materials for further study of cold-adaptation mechanisms and interaction with the host P. fluorescens. [ABSTRACT FROM AUTHOR]

Solution-based perovskite nanoparticles have been intensively studied in the past few years due to their applications in both photovoltaic and optoelectronic devices. Here, based on the common ground between solution-based perovskite and random lasers, we have studied the mirrorless lasing actions in self-assembled perovskite nanoparticles. After synthesis from a solution, discrete lasing peaks have been observed from optically pumped perovskites without any well-defined cavity boundaries. We have demonstrated that the origin of the random lasing emissions is the scattering between the nanostructures in the perovskite microplates. The obtained quality (Q) factors and thresholds of random lasers are around 500 and 60 µJ/cm², respectively. Both values are comparable to the conventional perovskite microdisk lasers with polygon-shaped cavity boundaries. From the corresponding studies on laser spectra and fluorescence microscope images, the lasing actions are considered random lasers that are generated by strong multiple scattering in random gain media. In additional to conventional single-photon excitation, due to the strong nonlinear effects of perovskites, two-photon pumped random lasers have also been demonstrated for the first time. We believe this research will find its potential applications in low-cost coherent light sources and biomedical detection. [ABSTRACT FROM AUTHOR]