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Bacteria-based self-healing concrete has become an effective approach to mitigate microcracks in the concrete structure. However, there are still doubts about when to use vegetative cells or spores of Bacillus sphaericus as a healing agent. Thus, this research aims to give recommendations regarding this choice. Spores and cells were encapsulated into expanded clay aggregate to protect them from the harsh environment of fresh mortar. The viability of cells and spores after encapsulation was investigated. The 28- and 90-day mortar compressive strength was analysed. The healing performance of the resulting mortar samples that were cracked at the age of 28 and 90 days has also been observed. The results show that both cells and spores were still active after encapsulation. The yeast extract added to mortar containing spores decreased the compressive strength of the mortar compared to the reference sample. From the healing performance result, it seems that the spores are more suitable for mitigating microcracks in aged mortar, while cells are more suitable for mitigating early-age cracks in the mortar.

Micro-crack is the start of concrete deterioration and failure, though it does not decrease the bearing capacity in the beginning. In order to prolong the service life of existing concrete structures, it is important to repair the existing micro-cracks before they develop into large cracks, which are much more harmful. Bio-genic CaCO3 from microbially induced carbonate precipitation (MICP) process is proved to be a promising crack repair material due to its environmental friendliness and super compatibility with cementitious matrix. In this study, MICP based repair technology was applied to repair micro-cracks. The influence of crack environment and repair technique on the precipitation of bio-CaCO3 was investigated. Results shown that moderate alkali pH had limited effect on the properties of bio-CaCO3. Bacteria could still induce the CaCO3 precipitation in crack if it was saturated with Ca2+ containing deposition medium. Crack of a width 0.5mm can be fully sealed within 3 days by use of a controlled injection technique.

Thermally activated delayed fluorescent (TADF) and phosphorescent blue organic light‐emitting diodes (OLEDs) have been developed to overcome the relatively low triplet exciton utilization of traditional fluorescent OLEDs. However, broad emission spectra originating from charge transfer process limits the commercial application of such blue OLEDs. Herein, an effective phosphor‐sensitized fluorescent (PSF) OLED device structure was designed. PSF OLED exhibited a maximum blue index (BI) of 508 cd/A/CIEy with CIEy of 0.060, which has been the highest efficiency result reported for PSF deep‐blue OLEDs. Impressively, the sensitized OLEDs maintained blue index of 407 cd/A/CIEy, narrow emission spectra (FWHM = 17 nm) and high color purity (CIEy = 0.046), revealing the attractive technical advantages and commercial application potential. [ABSTRACT FROM AUTHOR]

Thermally activated delayed fluorescent (TADF) and phosphorescent blue organic light‐emitting diodes (OLEDs) have been developed to overcome the relatively low triplet exciton utilization of traditional fluorescent OLEDs. However, broad emission spectra originating from charge transfer process limit the commercial application of such blue OLEDs. Herein, an effective phosphor‐sensitized fluorescent (PSF) OLED device structure was designed. PSF OLED exhibited a maximum blue index (BI) of 508 cd/A/CIEy with CIEy of 0.060, which has been the highest efficiency result reported for PSF deep‐blue OLEDs. A nearly 100% improvement in operational lifetime LT95 (L/L0 = 95%) was achieved successfully by using lower triplet energy (T1) and deuterated host materials. Impressively, the sensitized OLEDs maintained BI of 407 cd/A/CIEy, narrow emission spectra (FWHM = 17 nm), and high color purity (CIEy = 0.046), revealing the attractive technical advantages and commercial application potential. [ABSTRACT FROM AUTHOR]

The traditional Continuously Variable Transmission （CVT） dynamic control strategy takes the maximum engine power as the control target. As CVT efficiency varies greatly under different loads， the maximum engine power cannot guarantee the maximum driving power at the same time. For this， the matrix optimization algorithm is designed to calculate the CVT dynamic speed ratio under different pedal opening and vehicle speed with the maximum driving power as the target. A whole vehicle model is established by using GT-drive software， and the control strategies before and after optimization are simulated and compared. The result indicates that the optimized control strategy can improve the driving power and the maximum vehicle speed to different degrees under each pedal opening.