Flexible thermoelectrics is a synergy of flexible electronics and thermoelectric energy conversion. In this work, we fabricated flexible full-inorganic thermoelectric power generation modules based on doped silver chalcogenides.

Abstract. Canopy architecture has been a major target in crop breeding for improved yields. Whether crop architectures in current elite crop cultivars can be modified for increased canopy CO 2 uptake rate (A c ) under elevated atmospheric CO 2 concentrations (C a ) is currently unknown. To study this question, we developed a new model of canopy photosynthesis, which includes three components: (i) a canopy architectural model; (ii) a forward ray tracing algorithm; and (iii) a steadystate biochemical model of C 3 photosynthesis. With this model, we demonstrated that the A c estimated from 'average' canopy light conditions is~25% higher than that from light conditions at individual points in the canopy. We also evaluated theoretically the influence of canopy architectural on A c under current and future C a in rice. Simulation results suggest that to gain an optimal A c for the examined rice cultivar, the stem height, leaf width and leaf angles can be manipulated to enhance canopy photosynthesis. This model provides a framework for designing ideal crop architectures to gain optimal A c under future changing climate conditions. A close linkage between canopy photosynthesis modelling and canopy photosynthesis measurements is required to fully realise the potential of such modelling approaches in guiding crop improvements.

By utilizing the interaction between Cu and CNTs, a record-high zT of 2.4 has been achieved in Cu2Se/CNT hybrid materials.

Thermoelectric materials require an optimum carrier concentration to maximize electrical transport and thus thermoelectric performance. Element-doping and composition off-stoichiometry are the two general and effective approaches to optimize carrier concentrations, which have been successfully applied in almost all semiconductors. In this study, we propose a new strategy coined as bonding energy variation to tune the carrier concentrations in Cu2Se-based liquid-like thermoelectric compounds. By utilizing the different bond features in Cu2Se and Cu2S, alloying S at the Se-sites successfully increases the bonding energy to fix Cu atoms in the crystal lattice to suppress the formation of Cu vacancies, leading to much lowered carrier concentrations toward the optimum value. Combing the lowered electrical and lattice thermal conductivities, and the relatively good carrier mobility caused by the weak alloy scattering potential, ultrahigh zTs are achieved in slightly S doped Cu2Se with a maximum value of 2.0 at 1000 K, 30% higher than that in nominallystoichiometric Cu2Se.The table of contents entry: Beyond element-doping and composition off-stoichiometry, we propose a new strategy coined as bonding energy variation to tune the carrier concentrations in Cu2Se-based liquid-like thermoelectric compounds, leading to a maximum zT value of 2.0 at 1000 K, 30% higher than that in nominally-stoichiometric Cu2Se.

SUMMARYEr71 mutant embryos are nonviable and lack hematopoietic and endothelial lineages. To further define the functional role for ER71 in cell lineage decisions, we generated genetically modified mouse models. We engineered an Er71-EYFP transgenic mouse model by fusing the 3.9 kb Er71 promoter to the EYFP reporter gene. Using FACS and transcriptional profiling, we examined the EYFP + population of cells in Er71 mutant and wild-type littermates. In the absence of ER71, we observed an increase in the number of EYFP-expressing cells, increased expression of the cardiac molecular program and decreased expression of the hematoendothelial program, as compared with wild-type littermate controls. We also generated a novel Er71-Cre transgenic mouse model using the same 3.9 kb Er71 promoter. Genetic fate-mapping studies revealed that the ER71-expressing cells give rise to the hematopoietic and endothelial lineages in the wild-type background. In the absence of ER71, these cell populations contributed to alternative mesodermal lineages, including the cardiac lineage. To extend these analyses, we used an inducible embryonic stem/embryoid body system and observed that ER71 overexpression repressed cardiogenesis. Together, these studies identify ER71 as a critical regulator of mesodermal fate decisions that acts to specify the hematopoietic and endothelial lineages at the expense of cardiac lineages. This enhances our understanding of the mechanisms that govern mesodermal fate decisions early during embryogenesis.

Cu8GeSe6 argyrodite-type compound is a new thermoelectric material which exhibits extremely low lattice thermal conductivity and high thermoelectric performance.

A GeTe-based TE module with a high energy conversion efficiency of 7.8% under ΔT = 500 K is fabricated.

zT = S 2 σT/κ, where S is the Seebeck coefficient, σ is the electrical conductivity, T is the absolute temperature, and κ is the thermal conductivity consisting of the lattice thermal conductivity (κ L ) and carrier thermal conductivity (κ c ). [3] Doping external elements is a routine but effective approach to improve zT because it can tune carrier concentration or band structure to optimize PF (S 2 σ) and introduce point defects to suppress κ L . [4][5][6][7][8] However, the application of this approach highly relies on the kind and solution limit of the external elements in the host lattice. Among the numerous TE materials reported so far, GeTe is a special one because its lattice can accommodate many external elements with relatively large solution limits. Typical dopants are Sb (≈10% at Ge-sites), Bi (≈10% at Ge-sites), Pb (≈10% at Ge-sites), and Mn (>50% at Ge-sites). [9][10][11][12][13][14] Upon introducing these dopants, the κ L of GeTe can be reduced from 3.0 to around 1.0 W m −1 K −1 at 300 K. Moreover, the lattice of GeTe can simultaneously accommodate two or multiple kinds of external elements with distinct atomic mass and radius, such as (Mn, Sb), (Mn, Bi), (Cu, Sb), (In, Sb), (In, Bi), (Cr, Sb), (Ti, Sb), (Pb, Sb), and (Pb, Bi), which can further reduce the κ L to as low as 0.5 W m −1 K −1 . [15][16][17][18][19][20][21][22][23][24][25] Combining the optimized electrical transport properties by these external elements, GeTe-based compounds demonstrate high zTs in the intermediate temperature range. Among the single-doped GeTe-based compounds, Ge 0.9 Sb 0.1 Te and Ge 0.9 Bi 0.06 Te demonstrate zTs above 1.5 at 700 K. [9,10] Among the double-or multiple-doped GeTe-based compounds, Ge 0.89 Sb 0.1 In 0.01 Te, Ge 0.89 Cu 0.06 Sb 0.08 Te, Ge 0.86 Pb 0.1 Bi 0.04 Te, and Ge 0.9 Cd 0.05 Bi 0.05 Te demonstrate high zTs exceeding the level of 2.0. [15][16][17]26] Currently, GeTe-based compounds are among the best TE materials in thermoelectrics.The κ L reduction in doped GeTe-based compounds are mainly caused by the strain field and mass fluctuations introduced by the dopants. Theoretically, κ L is given by [27,28] High-efficiency thermoelectric (TE) technology is determined by the performance of TE materials. Doping is a routine approach in TEs to achieve optimized electrical properties and lowered thermal conductivity. However, how to choose appropriate dopants with desirable solution content to realize high TE figure-of-merit (zT) is very tough work. In this study, via the use of large mass and strain field fluctuations as indicators for low lattice thermal conductivity, the combination of (Mg, Bi) in GeTe is screened as very effective dopants for potentially high zTs. In experiments, a series of (Mg, Bi) co-doped GeTe compounds are prepared and the electrical and thermal transport properties are systematically investigated. Ultralow lattice thermal conductivity, about 0.3 W m −1 K −1 at 600 K, is obtained in Ge 0.9 Mg 0.04 Bi 0.06 Te due to the introduced large mass and strain field fluctuations by (Mg, Bi)...