III-nitride heteroepitaxial films approaching bulk-class quality

AlN growth on nano-patterned AlN templat

Comprehensive Study of Volatile Compounds in Two Australian Rosé Wines: Aroma Extract Dilution Analysis (AEDA) of Extracts Prepared Using Solvent-Assisted Flavor Evaporation (SAFE) or Headspace Solid-Phase Extraction (HS-SPE)

Two rosé wines, representing a tropical and a fruity/floral style, were chosen from a previous study for further exploration by aroma extract dilution analysis (AEDA) and quantitative analysis. Volatiles were extracted using either liquid–liquid extraction (LLE) followed by solvent-assisted flavor evaporation (SAFE) or a recently developed dynamic headspace (HS) sampling method utilizing solid-phase extraction (SPE) cartridges. AEDA was conducted using gas chromatography–mass spectrometry/olfactometry (GC-MS/O) and a total of 51 aroma compounds with a flavor dilution (FD) factor ≥3 were detected. Quantitative analysis of 92 volatiles was undertaken in both wines for calculation of odor activity values. The fruity and floral wine style was mostly driven by 2-phenylethanol, β-damascenone, and a range of esters, whereas 3-SHA and several volatile acids were seen as essential for the tropical style. When extraction methods were compared, HS-SPE was as efficient as SAFE for extracting most esters and higher alcohols, which were associated with fruity and floral characters, but it was difficult to capture volatiles with greater polarity or higher boiling point that may still be important to perceived wine aroma

Mutual Tailored Bimetallic Rh–Co Supported on La Modified SiO₂ for Direct Ethanol Synthesis from Syngas

In this work, Rh–Co/La2O3–SiO2 showed excellent selectivity to ethanol for direct ethanol synthesis from syngas. The best catalyst exhibited 42.8% selectivity to ethanol with CO conversion of 12.3% and in 145 h’ running maintained stable at 553 K, 3 MPa and GHSV of 3900 mL (gcat h)−1. The investigate results indicated that the interaction of cobalt denoting electron to rhodium adjusted the amounts of carbon monoxide adsorbed associatively and dissociatively, and maybe created a new active site pair of Rh0/Coδ+ for generating ethanol. Moreover, the mutually doping effect could dilute Co and Rh atoms in Rh–Co nanoparticles (NPs), which effectively suppressed the formation of C2+H and C3+OH, and thus led to the high ethanol selectivity and good anticoking property assisting with the carbon eliminating effect of La2O3. Owing to the high dispersion of Rh–Co NPs, the catalyst showed good activity and high resistance to sintering

Theoretically Evaluating Two-Dimensional Tetragonal Si₂Se₂ and SiSe₂ Nanosheets as Cathode Catalysts for Alkali Metal–O₂ Batteries

Nonaqueous alkali metal (AM)–O2 batteries are promising next-generation energy storage devices due to their outstanding specific capacity and energy density. However, the high charge–discharge overpotential and slow electrochemical reactions limit their development. Highly active cathode catalysts can solve this problem. Based on first-principles calculations, we theoretically explore the application potential of Si2Se2 and SiSe2 nanosheets as potential cathode electrocatalysts. Different electrochemical reduction paths are proposed for understanding the discharge process. For example, for Li–O2 battery, the main products on the electrocatalyst surface are LiO2 and Li2O2, and the charge/discharge overpotential of SiSe2 is less than 0.46 V. The main products are NaO2 and Na2O2 for Na–O2 battery, and the charge/discharge overpotentials are less than 0.73 V. There is only one catalytic product of K–O2 battery, which is KO2. Specially, the charge/discharge overpotential of Si2Se2 is significantly low, only 0.31 V for K–O2 battery. In addition, we found that neither Si2Se2 nor SiSe2 promoted the formation of the side product Li2CO3/Na2CO3 or caused the decomposition of the dimethyl sulfoxide electrolyte, suggesting that Si2Se2 and SiSe2 can effectively improve the reversible cycle life of AM–O2 batteries

N‑Heterocyclic Carbene-Catalyzed Highly Enantioselective Macrolactonization to Access Planar-Chiral Macrocycles

An N-heterocyclic carbene (NHC)-catalyzed atroposelective macrolactonization has been disclosed. This approach affords planar-chiral macrocycles in high yields with excellent enantioselectivities over a broad substrate scope. Controlled experiments suggest that the enantioselectivity might arise from the cation–n interaction between the acyl azolium and the electron-rich moiety in the substrate. This mechanism is supported by density functional theory calculations, which also suggest an important π–π interaction in stabilizing the transition state

Image_6_Topography and structural diversity regulate ecosystem multifunctionality in a subtropical evergreen broad-leaved forest.JPEG

Forest functionality is generally considered a byproduct of forest diversity. Perhaps unsurprisingly, many researchers associate increasing multi-functionality with increasing diversity. Diversity, however, is an often-overused word that may describe a host of features, including the diversity of species, functional trait and structure. Furthermore, variable environmental features (such as topography) influence the interaction between forest plants and their function. Incorporating complex topography (like that associated with tropical and subtropical forests) into estimates of forest functionality is challenging and highly uncertain. In this paper, we applied structural equation models to disentangle the relative importance of topography and different components of what might be considered “plant diversity” to forest multifunctionality using repeated census of a 20-ha subtropical forest plot. We found that multifunctionality was principally influenced by structural diversity more so than either species composition or functional trait diversity. In our SEM model approach, we observed variations in topography could account for about 30% of variation in multifunctionality. Furthermore, variations in topography could indirectly influence forest multifunctionality by changing species composition, functional trait diversity, and structural diversity. Our work highlights the importance of topography and forest structure in regulating subtropical forest multifunctionality on the local scale. This suggests future subtropical forest management should focus on regulating forest structure. Namely, our results suggest land managers must take topography (and the complex interaction between topography and plant diversity) into account in order to build robust and multifunctional forests.</p

Image_2_Topography and structural diversity regulate ecosystem multifunctionality in a subtropical evergreen broad-leaved forest.TIF

Forest functionality is generally considered a byproduct of forest diversity. Perhaps unsurprisingly, many researchers associate increasing multi-functionality with increasing diversity. Diversity, however, is an often-overused word that may describe a host of features, including the diversity of species, functional trait and structure. Furthermore, variable environmental features (such as topography) influence the interaction between forest plants and their function. Incorporating complex topography (like that associated with tropical and subtropical forests) into estimates of forest functionality is challenging and highly uncertain. In this paper, we applied structural equation models to disentangle the relative importance of topography and different components of what might be considered “plant diversity” to forest multifunctionality using repeated census of a 20-ha subtropical forest plot. We found that multifunctionality was principally influenced by structural diversity more so than either species composition or functional trait diversity. In our SEM model approach, we observed variations in topography could account for about 30% of variation in multifunctionality. Furthermore, variations in topography could indirectly influence forest multifunctionality by changing species composition, functional trait diversity, and structural diversity. Our work highlights the importance of topography and forest structure in regulating subtropical forest multifunctionality on the local scale. This suggests future subtropical forest management should focus on regulating forest structure. Namely, our results suggest land managers must take topography (and the complex interaction between topography and plant diversity) into account in order to build robust and multifunctional forests.</p

Image_11_Topography and structural diversity regulate ecosystem multifunctionality in a subtropical evergreen broad-leaved forest.JPEG

Forest functionality is generally considered a byproduct of forest diversity. Perhaps unsurprisingly, many researchers associate increasing multi-functionality with increasing diversity. Diversity, however, is an often-overused word that may describe a host of features, including the diversity of species, functional trait and structure. Furthermore, variable environmental features (such as topography) influence the interaction between forest plants and their function. Incorporating complex topography (like that associated with tropical and subtropical forests) into estimates of forest functionality is challenging and highly uncertain. In this paper, we applied structural equation models to disentangle the relative importance of topography and different components of what might be considered “plant diversity” to forest multifunctionality using repeated census of a 20-ha subtropical forest plot. We found that multifunctionality was principally influenced by structural diversity more so than either species composition or functional trait diversity. In our SEM model approach, we observed variations in topography could account for about 30% of variation in multifunctionality. Furthermore, variations in topography could indirectly influence forest multifunctionality by changing species composition, functional trait diversity, and structural diversity. Our work highlights the importance of topography and forest structure in regulating subtropical forest multifunctionality on the local scale. This suggests future subtropical forest management should focus on regulating forest structure. Namely, our results suggest land managers must take topography (and the complex interaction between topography and plant diversity) into account in order to build robust and multifunctional forests.</p

Image_3_Topography and structural diversity regulate ecosystem multifunctionality in a subtropical evergreen broad-leaved forest.TIF

Forest functionality is generally considered a byproduct of forest diversity. Perhaps unsurprisingly, many researchers associate increasing multi-functionality with increasing diversity. Diversity, however, is an often-overused word that may describe a host of features, including the diversity of species, functional trait and structure. Furthermore, variable environmental features (such as topography) influence the interaction between forest plants and their function. Incorporating complex topography (like that associated with tropical and subtropical forests) into estimates of forest functionality is challenging and highly uncertain. In this paper, we applied structural equation models to disentangle the relative importance of topography and different components of what might be considered “plant diversity” to forest multifunctionality using repeated census of a 20-ha subtropical forest plot. We found that multifunctionality was principally influenced by structural diversity more so than either species composition or functional trait diversity. In our SEM model approach, we observed variations in topography could account for about 30% of variation in multifunctionality. Furthermore, variations in topography could indirectly influence forest multifunctionality by changing species composition, functional trait diversity, and structural diversity. Our work highlights the importance of topography and forest structure in regulating subtropical forest multifunctionality on the local scale. This suggests future subtropical forest management should focus on regulating forest structure. Namely, our results suggest land managers must take topography (and the complex interaction between topography and plant diversity) into account in order to build robust and multifunctional forests.</p