Colloidal Synthesis of MoSe2/WSe2 Heterostructure Nanoflowers via Two-Step Growth

The ability to control the active edge sites of transition metal dichalcogenides (TMDs) is crucial for modulating their chemical activity for various electrochemical applications, including hydrogen evolution reactions. In this study, we demonstrate a colloidal synthetic method to prepare core-shell-like heterostructures composed of MoSe2 and WSe2 via a two-step sequential growth. By overgrowing WSe2 on the surface of preexisting MoSe2 nanosheet edges, MoSe2-core/WSe2-shell heterostructures were successfully obtained. Systematic comparisons of the secondary growth time and sequential order of growth suggest that the low synthetic temperature conditions allow the stable overgrowth of shells rich in WSe2 on top of the core of MoSe2 with low Gibbs formation energy. The electrochemical analysis confirms that the catalytic activity correlates to the core-shell composition variation. Our results propose a new strategy to control the edge site activity of TMD materials prepared by colloidal synthesis, which is applicable to diverse electrochemical applications.

The architecture of phenotypic flexibility within a complex trait: an empirical case study using avian thermogenic performance

ABSTRACTReversible modifications to trait values can allow individuals to match their phenotypes to changing environmental conditions, a phenomenon known as phenotypic flexibility. A system’s capacity for flexibility may be determined by its underlying architecture, and these relationships can have important implications for both organismal adaptation and the evolvability of acclimatization responses. Theory provides two possible alternatives to explain the ways in which lower-level traits respond to environmental challenges and contribute to phenotypic flexibility in complex, whole-organism traits: symmorphosis predicts correspondence between structure and demand across all levels of a physiological system, while the alternative predicts that influence is concentrated in select elements of a physiological network. Here we provide a rich dataset — composed of 20 sub-organismal, physiological traits paired with whole-organism metabolic rates for 106 adult Dark-eyed Juncos (Junco hyemalis) — to explore the mechanistic basis of phenotypic flexibility in complex traits. When exposed to synthetic temperature cues, these individuals have previously been shown to increase their thermogenic capacity (Msum) and enhance their ability to maintain their body temperature in the cold. We show that the relationships among a number of the traits that contribute to Msum varied as the environmental context changed. Moreover, variation in Msum in response to temperature acclimation was correlated with only a handful of subordinate phenotypes. As a result, avian thermogenic flexibility does not appear to be a symmorphotic response. If this is generally true of complex traits, it suggests that simple and reversible modifications can significantly impact whole-organism performance, and thus that the evolution of phenotypic flexibility in a single component part could impart flexibility for the entire system.

Structure modulation of g-C3N4 in TiO2{001}/g-C3N4 hetero-structures for boosting photocatalytic hydrogen evolution

The structure of g-C3N4 in the prepared TiO2{001}/g-C3N4 hetero-structures could be modulated from BCN to CN-NS, CN-NC or CN-QD by tuning the synthetic temperature.

Research on the effects of hydrothermal synthesis conditions on the crystal habit of MIL-121

The investigation of the influence of hydrothermal synthesis conditions such as synthetic temperature, the amount of solvent, addition of additives including sodium hydroxide, lithium chloride and 2-methylimidazole on the morphology and size of MIL-121 was carried out. The experimental results indicated the significant impact of hydrothermal synthesis conditions on the morphologies and sizes of MIL-121 crystals. The synthesis temperature has little effect on the morphology, which is mainly reflected in the change of the aspect ratio, but the effect on the size is significant under low-temperature conditions. Additives have an important influence on the morphology and size of MIL-121. Our study provides a potential for the improvement of MIL-121 adsorption performance.

Preparation and luminescence properties of Li2.06Nb0.18Ti0.76O3:Eu3+ phosphors

New red phosphors with compositions of Li[Formula: see text]Nb[Formula: see text]Ti[Formula: see text]O3: [Formula: see text]Eu[Formula: see text] ([Formula: see text]–4[Formula: see text]wt.%) were prepared by using solid-state reactions. The phase structure and photoluminescence (PL) properties were studied as functions of synthetic temperature and Eu[Formula: see text] concentration. With the increase of synthetic temperature and Eu[Formula: see text] concentration, both the characteristic peaks of the excitation spectra monitored at 612[Formula: see text]nm and emission spectra excited at 396[Formula: see text]nm were remarkably enhanced. The intensity of peaks reaches a maximum when the content of Eu[Formula: see text] increases to [Formula: see text][Formula: see text]wt.% at 950∘C, Chromaticity Coordinate (CIE) of samples superior to the commercial red phosphors Y2O3:Eu[Formula: see text]. The internal quantum efficiency (QE) of Li[Formula: see text]Nb[Formula: see text]Ti[Formula: see text]O3:3[Formula: see text]wt.%Eu[Formula: see text] was 49.5%. These features show promising applications for near-ultraviolet (near-UV) chips-based LEDs.

Temperature-sensitive protein expression in protocells

We engineered a synthetic temperature regulation toolbox to enable protocells to sense and respond to heat, utilizing RNA thermometers.

OSSE for a sustainable marine observing network in the Sea of Marmara

An observing system simulation experiment (OSSE) is presented in the Sea of Marmara. A high-resolution ocean circulation model (FESOM) and an ensemble data assimilation tool (DART) are coupled. The OSSE methodology is used to assess the possible impact of a FerryBox network in the eastern Sea of Marmara. A reference experiment without assimilation is performed. Then, synthetic temperature and salinity observations are assimilated along the track of the ferries in the second experiment. The results suggest that a FerryBox network in the Sea of Marmara has potential to improve the forecasts significantly. The salinity and temperature errors get smaller in the upper layer of the water column. The impact of the assimilation is negligible in the lower layer due to the strong stratification. The circulation in the Sea of Marmara, particularly the Bosphorus outflow, helps to propagate the error reduction towards the western basin where no assimilation is performed. Overall, the proposed FerryBox network can be a good start to designing an optimal sustained marine observing network in the Sea of Marmara for assimilation purposes.