Humectants effect on aqueous fluids absorption of γ-irradiated PVA hydrogel followed by freeze thawing

To evaluate the effect of humectants such as glycerol, poly(vinyl alcohol)/glycerol (P/G) hydrogels were prepared by using γ-ray irradiation followed by freeze thawing (FT). The gel fraction ratio (G) and equilibrium swelling ratio (S) of the P/G hydrogels were investigated as functions of glycerol content and FT cycles. Interestingly, G increases while S decreases with increase in glycerol content. This result indicates that even if the glycerol is useful to improve the smoothness and moisture of the hydrogels, further consideration of conditioning the use of glycerol to improve the absorption of exudates from wounds for an advanced wound healing is needed.     

A New Perspective on Li–SO2 Batteries for Rechargeable Systems

Primary Li–SO₂ batteries offer a high energy density in a wide operating temperature range with exceptionally long shelf life and have thus been frequently used in military and aerospace applications. Although these batteries have never been demonstrated as a rechargeable system, herein, we show that the reversible formation of Li₂S₂O₄, the major discharge product of Li–SO₂ battery, is possible with a remarkably smaller charging polarization than that of a Li–O₂ battery without the use of catalysts. The rechargeable Li–SO₂ battery can deliver approximately 5400 mAh g^?1 at 3.1 V, which is slightly higher than the performance of a Li–O₂ battery. In addition, the Li–SO₂ battery can be operated with the aid of a redox mediator, exhibiting an overall polarization of less than 0.3 V, which results in one of the highest energy efficiencies achieved for Li–gas battery systems.     

Rate measurement of D(0)-->K+pi(-)pi(0) and constraints on D(0) -- D(0) mixing

We present an observation and time-integrated rate measurement of the decay D(0)-->K(+)pi(-)pi(0) produced in 9 fb(-1) of e(+)e(-) collisions near the Upsilon(4S) resonance. The signal is inconsistent with an upward fluctuation of the background by 4.9 standard deviations. We measured the time-integrated rate of D(0)-->K(+)pi(-)pi(0) normalized to the rate of D(0)-->K(+)pi(-)pi(0) to be 0.0043(+0.0011)(-0.0010) (stat)+/-0.0007 (syst). This decay can be produced by doubly Cabibbo-suppressed decays or by the D(0) evolving into a D(0) through mixing, followed by a Cabibbo-favored decay to K(+)pi(-)pi(0). We also found the CP asymmetry A = (9(+25)(-22))% be consistent with zero.     

A fast algorithm to sample the number of vertexes and the area of the random convex hull on the unit square

We propose an algorithm to sample the area of the smallest convex hull containing \(n\) sample points uniformly distributed over unit square. To do it, we introduce a new coordinate system for the position of vertexes and re-write joint distribution of the number of vertexes and their locations in the new coordinate system. The proposed algorithm is much faster than existing procedure and has a computational complexity on the order of \(O(T)\) , where \(T\) is the number of vertexes. Using the proposed algorithm, we numerically investigate the asymptotic behavior of functionals of the random convex hull. In addition, we apply it to finding pairs of stocks where the returns are dependent on each other on the New York Stock Exchange.     

Measurement of B(D+-->K(*0)l(+)nu(l))

Using 13.53 fb(-1) of CLEO data, we have measured the ratios of the branching fractions R(+)(e),R(+)(mu) and the combined branching fraction ratio R(+)(l), defined by R(+)(l)=[B(D+-->K(*0)l(+)nu(l))]/[B(D+-->K-pi(+)pi(+))]. We find R(+)(e)=0.74+/-0.04+/-0.05, R(+)(mu)=0.72+/-0.10+/-0.05, and R(+)(l)=0.74+/-0.04+/-0.05, where the first and second errors are statistical and systematic, respectively. The known branching fraction B(D+-->K-pi(+)pi(+)) leads to B(D+-->K(*0)e(+)nu(e))=(6.7+/-0.4+/-0.5+/-0.4)%, B(D+-->K(*0)mu(+)nu(mu))=(6.5+/-0.9+/-0.5+/-0.4)%, and B(D+-->K(*0)l(+)nu(l))=(6.7+/-0.4+/-0.5+/-0.4)%, where the third error is due to the uncertainty in B(D+-->K-pi(+)pi(+)).     

First observation of the decays B(0) --> D(*-)p_p pi+ and B(0) --> D(*-)p_n

We report the first observation of exclusive decays of the type B-->D(*)N_NX, where N is a nucleon. Using a sample of 9.7x10(6)B_B pairs collected with the CLEO detector operating at the Cornell Electron Storage Ring, we measure the branching fractions B(B0-->D(*-)p_p pi(+)) = (6.5(+1.3)(-1.2)+/-1.0)x10(-4) and B(B0-->D(*-)p_n) = (14.5(+3.4)(-3.0)+/-2.7)x10(-4). Antineutrons are identified by their annihilation in the CsI electromagnetic calorimeter.     

Superior Rechargeability and Efficiency of Lithium–Oxygen Batteries: Hierarchical Air Electrode Architecture Combined with a Soluble Catalyst

The lithium–oxygen battery has the potential to deliver extremely high energy densities; however, the practical use of Li‐O₂ batteries has been restricted because of their poor cyclability and low energy efficiency. In this work, we report a novel Li‐O₂ battery with high reversibility and good energy efficiency using a soluble catalyst combined with a hierarchical nanoporous air electrode. Through the porous three‐dimensional network of the air electrode, not only lithium ions and oxygen but also soluble catalysts can be rapidly transported, enabling ultra‐efficient electrode reactions and significantly enhanced catalytic activity. The novel Li‐O₂ battery, combining an ideal air electrode and a soluble catalyst, can deliver a high reversible capacity (1000 mAh g^?1) up to 900 cycles with reduced polarization (about 0.25 V).     

The synthesis and spectral properties of a stimuli-responsive D–π–A charge transfer dye based on indole donor and 2-cyanomethylene-3-cyano-4,5,5-trimethyl-2,5-dihydrofuran acceptor moieties

A particular chromogenic and fluorophoric dye chemosensor was designed and synthesized, which was based on the stimuli-responsive D–π–A charge transfer system. Indole moiety as a donor unit and furan moiety as an acceptor unit were used. This prepared dye sensor showed the selective fluoride ion sensing effects in UV–vis absorption and fluorescence emission properties. Clear absorption changes and highly selective fluorescence quenching effects with fluoride ion were determined. Experimental data and images were collected and supported to provide a better understanding of this particular dye sensor.     

A pot-economical and green synthesis of novel (benzo[d]imidazo[2,1-b]thiazol-3-yl)-2H-chromen-2-one in ethanol–PEG-600 under catalyst-free conditions

A catalyst-free, environmentally benign, and simple one-pot multi-component protocol has been developed for the efficient synthesis of novel (benzo[d]imidazo[2,1-b]thiazol-3-yl)-2H-chromen-2-one derivatives in excellent yields using ethanol-PEG-600. This novel and green protocol have the advantages of shorter reaction times, high conversions, and follow the group-assisted-purification (GAP) chemistry process, which can avoid traditional purifications, chromatography and recrystallization. This is the first report for the synthesis of benzo[d]imidazo[2,1-b]thiazol-3-yl)-2H-chromen-2-one.