Wrennbro7752

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A liquid marble (LM) is a droplet coated with microparticles that isolate the liquid interior from its surroundings, making it perfectly non-wetting. This attractive feature allows the LM to perform useful tasks such as coalescence, targeted delivery, and controlled release. The non-wetting characteristic also allows the LM to float on a carrier liquid. see more The growing number of applications in digital microfluidics requires further insights into the fundamental properties of a LM such as its effective surface tension. Although the coating provides the LM with various desirable characteristics, its random construction presents a major obstacle to accurate optical analysis. This paper presents a novel method to measure the effective surface tension of a floating LM using X-ray imaging and curve fitting procedures. X-ray imaging reveals the true LM liquid-air interface hidden by the coating particles. Analysis of this interface showed that the effective surface tension of a LM is not significantly different from that of its liquid content. This indicates that the particle coating might not have significantly altered the behaviour of the liquid interface. We also found that our method is sensitive enough to detect the variations across individual LMs.For quantum dot sensitized solar cells (QDSSCs), modifying conservative polysulfide electrolytes with polymer additives has been proven as an effective method to control charge recombination processes at the TiO2/QDs/electrolyte interface and to accomplish efficient cell devices. In this respect, the polysulfide electrolyte is modified with polymeric and sulfur-rich graphitic carbon nitride (SGCN) to enhance the photovoltaic performance of QDSSCs. For the first time, SGCN is used to passivate surface trap states and act as the steric hindrance between TiO2/QDs/electrolyte interfaces. The QDSSCs fabricated with GCN and SGCN additives exhibited higher efficiencies, especially improved short-circuit current (JSC) and fill factors (FFs) than those of the liquid electrolyte. Cu-In-S sensitized QDSSCs constructed with GCN and SGCN additives exhibited efficiencies of 6.73% and 7.13%, respectively, whereas the liquid electrolytes delivered an efficiency of 6.16%. Additionally, the applicability of SGCN additives in various Cu-based QDSSCs to enhance their photovoltaic performance is further verified using Cu-In-Se QDSSCs. An increase in the conversion efficiencies of QDSSCs with SGCN additives is possibly due to (1) their electron-rich surface which can act as an obstacle for electron-hole recombination, thereby suppressing the back-transfer of photo-induced electrons to the QD/electrolyte interface; (2) SGCN facilitates the reduction of Sn2- to S2- redox couple, thus providing holes towards the QDs/electrolyte more efficiently. Overall, this work provides an innovative and economic additive to modify polysulfide electrolytes, thereby controlling the TiO2/QDs/electrolyte interfaces of QDSSCs.The first nickel-catalyzed oxidative domino Csp3-H/N-H double isocyanide insertion reaction of acetamides with isocyanides has been developed for the synthesis of pyrrolin-2-one derivatives. A wide range of acetamides bearing various functional groups are compatible with this reaction system by utilizing Ni(acac)2 as a catalyst. In this transformation, isocyanide could serve as a C1 connector and insert into the inactive Csp3-H bond, representing an effective way to construct heterocycles.The integration of membranes in microfluidic devices has been extensively exploited for various chemical engineering and bioengineering applications over the past few decades. To augment the applicability of membrane-integrated microfluidic platforms for biomedical and tissue engineering studies, a biologically friendly fabrication process with naturally occurring materials is highly desired. The in situ preparation of membranes involving interfacial reactions between parallel laminar flows in microfluidic networks, known as the flow-assembly technique, is one of the most biocompatible approaches. Membranes of many types with flexible geometries have been successfully assembled inside complex microchannels using this facile and versatile flow-assembly approach. Chitosan is a naturally abundant polysaccharide known for its pronounced biocompatibility, biodegradability, good mechanical stability, ease of modification and processing, and film-forming ability under near-physiological conditions. Chitosan membranes assembled by flows in microfluidics are freestanding, robust, semipermeable, and well-aligned in microstructure, and show high affinity to bioactive reagents and biological components (e.g. biomolecules, nanoparticles, or cells) that provide facile biological functionalization of microdevices. Here, we discuss the recent developments and optimizations in the flow-assembly of chitosan membranes and chitosan-based membranes in microfluidics. Furthermore, we recapitulate the applications of the chitosan membrane-integrated microfluidic platforms dedicated to biology, biochemistry, and drug release fields, and envision the future developments of this important platform with versatile functions.Dual-emitting manganese ion doped LaM1-xAl11-yO19 (M = Mg, Zn) phosphors were prepared by substituting Zn2+/Mg2+ with Mn2+ and replacing Al3+ with Mn4+. The LaM1-xAl11-yO19xMn2+,yMn4+ phosphors show a narrow green emission band of the Mn2+ ions at 514 nm and a red emission band of the Mn4+ ions at 677 nm. In addition, the thermal stability of luminescence shows that the response of Mn2+ and Mn4+ to the temperature is obviously different in LaMAl11O19, implying the potential of the prepared phosphors as optical thermometers. The decay lifetime of Mn4+ was changed with temperature due to the different fluorescence intensity ratios of Mn2+ and Mn4+, and a dual-mode optical temperature-sensing mechanism was studied in the temperature range of -50-200 °C. The maximum relative sensitivities (Sr) are calculated as 3.22 and 3.13% K-1, respectively. The unique optical thermometric features demonstrate the application potential of LaMAl11O19Mn2+,Mn4+ in optical thermometry.