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A self-assembled three-dimensional (3D) nanomaterial, blue phase liquid crystal (BPLC), with elastic deformation is the aim of a stimuli-responsive material because it combines the 3D photonic nanostructure and the rubber elasticity of the elastomer network. However, there is still a lack of a flexible approach to preparing BPLC films with high elastic deformation and a low glass-transition temperature. Here, we develop a reproducible and scalable two-step protocol of the thiol-acrylate Michael addition (TAMA)–photopolymerization reaction approach for the preparation of high-performance, low glass-transition temperature, and uniform BPLC films. Linear chain extension occurs through the TAMA reaction, and the cross-link density and molecular weight can be programed by varying the reaction time, resulting in the phase transition from blue phase I to the chiral nematic phase. The cross-linking density, molecular weight, and resulting structure can be frozen by forming an elastic network using photopolymerization. The results show that the increase of elastic deformation by 3 times, shift of the structural color >186 nm, and lowering of the glass-transition temperature to −34.93 °C are successfully achieved. In addition, the BPLC film pattern can sustain repeatable, rapid, and continuous elastic deformation and a uniform structural color change when triggered by multiple stimuli of temperature, stretching, and organic vapor. This work provides new insights into customizable stimuli-responsive 3D photonic nanostructured materials, facilitating their application in sensing, display, and anti-counterfeiting. [ABSTRACT FROM AUTHOR]

A comparison of rate constants measured for an intervalence (IV) compounds with electron-transfer parameters obtained from its optical absorption spectrum is done using resonance Raman analysis. It is suggested that the Zhu-Nakamura preexponential factor provides good consistency for the ESR rate constants using a value, averaged single-mode which closer to those predicted from the resonance Raman spectroscopic data but need slightly higher electronic coupling than [V.sub.Hush].

The Zhu-Nakamura (ZN) formulas were used to treat the nonadiabatic transition in the Marcus inverted electronic transfer reaction and determine the effect of the nuclear tunneling. The adiabatic suppression is reduced by the effect of nuclear tunneling when compared to the case where the Landau-Zener formula is used.

The theoretical studies on electron transfer (ET) rates of a charge localized intervalence radical cation of bis(hydrazine) are reported. The results showed that electron-transfer rates are heavily dependent on the isomer geometries.

The crystal structure of [alpha]-phycoerythrocyanin with its chromophore in the E-configuration is compared with the Z-configuration found in trimeric phycoerythrocyanin (PEC) to reveal the structural bases of the isomerization. The photochemistry in [alpha]-PEC is coupled to two regions, the H4-H5 and H7-H8 loops where large structural changes occur.

The generalized nonadibatic transition-state theory (NA-TST) is applied to analyze the electron transfer with use of the Zhu-Nakamura (ZN) formulas of nonadiabatic transition in the case of fast dielectric relaxation. The results are coincident with the perturbation theory in the weak electronic coupling limit, while in the intermediate to strong electronic coupling regime where the perturbation theory breaks down the present results have agreed well with those from the quantum mechanism flux-flux correlation function within the model of effective one-dimensional mode.

A systematic, theoretical investigation on structure-property correlations in polyfluorenes (PFs) derived from the chain morphology, oligomer length and chemical substituent is presented. The results estimated the energy gaps of the PFs by extrapolations from excitation energies of oligofluorenes up to 21 fluorenone units.

The electronic structure and stability of Be5, Be5(super +1), Be5(super -1) clusters are investigated at the B3LYP, B3PW91, and MP2 levels of theory, along with the 6-311G basis set for neutral and cationic clusters and the 6-311+G basis set for anion clusters. The study identified six Be5, six Be5(super +1), and six Be5(super -1) isomers.

Molecularly imprinted polymers (MIP1 and MIP2) were synthesized using acrylamide as the functional monomer and acetic acid and ethanedioic acid as the template, respectively. Textural properties of MIPs and nonimprinted polymer (NIP) were characterized by an N2 adsorption experiment, thermogravimetric analysis, and Fourier transform infrared spectroscopy. NO2 basic adsorption conditions were set as 40 °C for the temperature, 100 mL/min for the flow rate, and 1000 ppm for the NO2 concentration through fixed-bed breakthrough experiments, and at these conditions, the NO2 adsorption capacity of MIP1, MIP2, and NIP was 0.58, 0.63, and 0.51 mg/g, respectively. The NO2 adsorption performance was nearly unaffected by O2; however, SO2 and CO2 inhibited NO2 adsorption severely. The H2O molecule had fewer negative effects on NO2adsorption because of the large number of hydrophobic groups--(CH2-CH)n--in polymers and the hydrogen bond force between H2O molecules. [ABSTRACT FROM AUTHOR]

A biofunctional polymer-lipid hybrid high-density lipoprotein-mimicking nanoparticle (HNP) loading anti-miR155 was constructed for combined antiatherogenic effects on macrophages. The HNP consisted of an anti-miR155 core condensed by acid-labile polyethylenimine (acid-labile PEI) polymers and a lipid bilayer coat that was decorated with apolipoprotein A-1, termed acid-labile PEI/HNP. The acid-labile PEI was synthesized with low-molecular-weight PEI and glutaraldehyde to reduce the cytotoxicity and facilitate nucleic acids escaping from acidic endolysosomes. The increased silencing efficiency of acid-labile PEI/HNP was ascribed to the clathrin-mediated endocytosis and successful endolysosomal escape. Decreased intracellular reactive oxygen species production and DiI-oxLDL uptake revealed the antioxidant activities of both anti-miR155 and HNP. Cholesterol efflux assay indicated the potential of HNP in reverse cholesterol transport. Collectively, the acid-labile PEI/HNP not only realized the efficacy of anti-miR155 in macrophages but also exerted the antiatherosclerotic biofunction of HNP. [ABSTRACT FROM AUTHOR]

Two new glycoluril diethers have been prepared, bearing strained cyclobutene and cyclobutane rings at the fused junction of the two imidazolidinone rings. The wide angle of the concave face of the cyclobutano derivative enabled the synthesis of cyclobutanocucurbit[5-8]uril, the largest member being the most significant achievement. A limited binding affinity study compared the new substituted family to classical cucurbit[5-8]uril. Surprisingly lower affinities were found, except for cyclobutanocucurbit[6]uril, which was 3.3-fold higher. [ABSTRACT FROM AUTHOR]

Methane dissociation on metal surfaces is of great commercial importance. The dissociation and recombination rate constants of CH4 on Ni(111) are calculated using the quantum instanton approach with the path integral Monte Carlo method. The Ni(111) lattice is treated rigidly, classically, and quantum mechanically to reveal the effects of lattice motion and quantum tunneling. For the dissociation of CH4, the rates have the smallest value on the rigid lattice, while they possess the largest value on the quantum lattice. For instance, at 300 K, the rates on the classical and quantum lattices are 5 and 12 times larger than that on the rigid lattice, respectively. The curve of the Arrhenius plot for the dissociation rates on the rigid lattice demonstrates that the quantum tunneling effect of the ruptured H atom is remarkable, while the nearly invariable dissociation rates at low temperatures on the quantum lattice confirm that the thermally assisted tunneling should be dominant at low temperatures. For the recombination of CH4, the quantum lattice still has rates that are much larger than that of the rigid lattice. For instance, the ratio of the recombination rates on the quantum and rigid lattices is 12 at 300 K. The quantum tunneling effect seems to play a minor role in the recombination rates on the rigid lattice; however, the thermally assisted tunneling is still very significant for the recombination process. [ABSTRACT FROM AUTHOR]

Biodegradable sizing agents from triethanolamine (TEA) modified soy protein could substitute poly(vinyl alcohol)(PVA) sizes for high-speed weaving of polyester and polyester/cotton yarns to substantially decrease environmental pollution and impel sustainability of textile industry. Nonbiodegradable PVA sizes are widely used and mainly contribute to high chemical oxygen demand (COD) in textile effluents. It has not been possible to effectively degrade, reuse or replace PVA sizes sofar. Soy protein with good biodegradability showed potential as warp sizes in our previous studies. However, soy protein sizes lacked film flexibility and adhesion for required high-speed weaving. Additives with multiple hydroxyl groups, nonlinear molecule, and electric charge could physically modify secondary structure of soy protein and lead to about 23.6% and 43.3% improvement in size adhesion and ability of hair coverage comparing to unmodified soy protein. Industrial weaving results showed TEA-soy protein had relative weaving efficiency 3% and 10% higher than PVA and chemically modified starch sizes on polyester/cotton fabrics, and had relative weaving efficiency similar to PVA on polyester fabrics, although with 3- 6% lower add-on. In addition, TEA-soy sizes had a BOD5/COD ratio of 0.44, much higher than 0.03 for PVA, indicating that TEA-soy sizes were easily biodegradable in activated sludge. [ABSTRACT FROM AUTHOR]

An unexpected 2,3-dihydrofuran ring opening process at the C(4)-C(5) bond has been developed. N-Bromosuccinimide and DABCO were used as the electrophilic halogen source and the catalyst, respectively. Mechanistic study indicates that moisture in the solvent might contribute to the reaction. The resulting brominated product could be further oxidized to yield a synthetically valuable 1,2-diketo building block. [ABSTRACT FROM AUTHOR]