2 research outputs found
An Optical Trap Combined with Three-Color FRET
We
developed a hybrid technique combining optical tweezers and
single-molecule three-color fluorescence resonance energy transfer
(FRET). In demonstrative experiments, we observed the force-sensitive
correlated motion of three helical arms of a Holliday junction and
identified the independent unfolding/folding dynamics of two DNA hairpins
of the same length. With 3 times the number of observable elements
of single-molecule FRET, this new instrument will enable the measurement
of the complex, multidimensional effects of mechanical forces in various
biomolecular systems, such as RNA and proteins
Extraordinary Off-Stoichiometric Bismuth Telluride for Enhanced n‑Type Thermoelectric Power Factor
Thermoelectrics
directly converts waste heat into electricity and
is considered a promising means of sustainable energy generation.
While most of the recent advances in the enhancement of the thermoelectric
figure of merit (<i>ZT</i>) resulted from a decrease in
lattice thermal conductivity by nanostructuring, there have been very
few attempts to enhance electrical transport properties, i.e., the
power factor. Here we use nanochemistry to stabilize bulk bismuth
telluride (Bi<sub>2</sub>Te<sub>3</sub>) that violates phase equilibrium,
namely, phase-pure n-type K<sub>0.06</sub>Bi<sub>2</sub>Te<sub>3.18</sub>. Incorporated potassium and tellurium in Bi<sub>2</sub>Te<sub>3</sub> far exceed their solubility limit, inducing simultaneous increase
in the electrical conductivity and the Seebeck coefficient along with
decrease in the thermal conductivity. Consequently, a high power factor
of ∼43 μW cm<sup>–1</sup> K<sup>–2</sup> and a high <i>ZT</i> > 1.1 at 323 K are achieved. Our
current synthetic method can be used to produce a new family of materials
with novel physical and chemical characteristics for various applications