Multi-C−C/C−N-Coupled Light-Emitting Aliphatic Terpolymers: N−H-Functionalized Fluorophore Monomers and High-Performance Applications

To circumvent costly fluorescent labeling, five nonconventional, multifunctional, intrinsically fluorescent aliphatic terpolymers ( 1 – 5 ) have been synthesized by C−C/C−N-coupled, solution polymerization of two non-emissive monomers with protrusions of fluorophore monomers generated in situ. These scalable terpolymers were suitable for sensing and high-performance exclusion of Cu^II, logic function, and bioimaging. The structures of the terpolymers, in situ attachment of fluorescent monomers, aggregation-induced enhanced emission, bioimaging ability, and super adsorption were investigated by ¹H and ¹³C NMR, EPR, FTIR, X-ray photoelectron, UV/Vis, and atomic absorption spectroscopy, thermogravimetric analysis, high-resolution transmission electron microscopy, dynamic light scattering, solid-state fluorescence, fluorescence imaging, and fluorescence lifetime measurements, as well as by isotherm, kinetics, and thermodynamic studies. The geometries and electronic structures of the fluorophores and the absorption and emission properties of the terpolymers were examined by DFT, time-dependent DFT, and natural transition orbital analyses. For 1 , 2 , and 5 , the limits of detection were determined to be 1.03×10⁻⁷, 1.65×10⁻⁷, and 1.77×10⁻⁷ m , respectively, and the maximum adsorption capacities are 1575.21, 1433.70, and 1472.21 mg g⁻¹, respectively.     

Cylindrically symmetric inhomogeneous cosmological models with viscous fluid and varying Λ

Cylindrically symmetric non-static cosmological models representing a bulk viscous fluid distribution have been obtained which are inhomogeneous and anisotropic. Without assuming anyadhoc law, we obtain a cosmological constant as a decreasing function of time. Various physical and geometrical features of the models are also discussed.     

Any two irreducible Markov chains of equal entropy are finitarily Kakutani equivalent

We show here that any two finite state irreducible Markov chains of the same entropy are finitarily Kakutani equivalent. By this we mean they are orbit equivalent by an invertible measure preserving mapping that is almost continuous and monotone in time when restricted to some cylinder set. Smorodinsky and Keane have shown that any two irreducible Markov chains of equal entropy and period are finitarily isomorphic. Hence, all that is necessary to obtain our result is to show that for every entropy h > 0 and period p ∈ ℕ there exists two irreducible Markov chains σ ₁, σ ₂ both of entropy h, where (1) σ ₁ is mixing (2) ς ₂ has period p and (3) σ1 and σ ₂ are finitarily Kakutani equivalent.     

On de-globalization in quantum chromodynamics

The recent discovery and resummation of a class of single logarithmic effects (non-global logs), has a significant impact on several QCD observables ranging from the classic Sterman-Weinberg jet definition to currently studied event shapes and rapidity gap observables. The discovery of the above effects overturns, for example, the common wisdom that hadronic energy flow in limited inter-jet regions is dictatedprimarily by the colour flow of the underlying hard partonic subprocess. We discuss some features of non-global logs and the rapid progress being made in estimating and controlling such corrections.     

Pt Dopant: Controlling the Ir Oxidation States toward Efficient and Durable Oxygen Evolution Reaction in Acidic Media

Dissolution of Ir oxides in Ir‐based catalysts, which is closely linked to the catalyst activity and stability toward the oxygen evolution reaction (OER) in acidic media, is a critical unresolved problem in the commercialization of water electrolysis. Doping foreign elements into the Ir oxides can accomplish an optimal combination of Ir oxidation states that is conducive to the leaching‐resistance of active catalytic sites. Here, it is reported that Pt doping into IrO_x‐based nanoframe is beneficial in both terms of activity and stability. The Pt‐doped IrO_x‐based nanoframe achieves the mass activity of 0.644 A mg^?1_Ir+Pt at 1.53 V_RHE, which is 15‐fold higher than that of the commercial IrO₂. During the accelerated durability test, the Ir^IV‐to‐Ir^III ratio of 5 is maintained in the presence of Pt dopant to effectively mitigate the degradation of Ir catalyst, leading to the superb catalyst durability in acidic media.     

Application of directed metalation in synthesis. Part 8: Interesting example of chemoselectivity in the synthesis of thioaurones and hydroxy ketones and a novel anionic ortho-Fries rearrangement used as a tool in the synthesis of thienopyranones and thiafluorenones

Chemoselective synthesis of thioaurones or 3-hydroxy benzo[b]thiophen-2-aryl ketones, 1-hydroxy naphtho[2,1-b]thiophen-2-aryl ketones and chalcones from N,N-diethyl-ortho-methyl sulfanyl aryl amides were described. (Benzo[b]thiophen-2-yl) alkylates and (naphtho[2,1-b]thiophen-2-yl) alkylates undergo a novel anionic ortho-Fries rearrangement leading to (3-hydroxy benzo[b]thiophen-2-yl) and (1-hydroxy naphtho[2,1-b]thiophen-2-yl) alkyl ketones. The hydroxy ketones were used as intermediates in the synthesis of wide range of benzothienopyranones and thiafluorenones.     

Synthesis of 1-trifluoroacetyl-3-dialkylamino-methyl-5-monosubstituted benzimidazoline-2-thiones using trifluoroacetic acid as an acylating agent

1-Trifluoroacetyl-3-dialkylaminomethyl-5-monosubstituted benzimidazoline-2-thiones have been synthesized from p-substituted anilines which were acetylated with trifluoroacetic acid. The trifluoroacetanilides were nitrated, reduced and cyclised with carbon disulphide in the presence of alcoholic potassium hydroxide and finally treated with formaldehyde and suitable secondary amines to afford the Mannich bases. The compounds were characterised by their analytical and spectral (ir, pmr, ¹⁹F and mass) data. The synthesized compounds have been screened for anti-inflammatory and analgesic activity and found to be active.     

Smooth transition from metastability to instability in phase separating protein solutions

For insight into the structure and dynamics of phases emerging upon crossing the metastability/instability boundary we monitor with optical microscopy, in real time and in real space, the generation of a dense liquid phase in high-concentration solutions of the protein lysozyme after temperature quenches into thermodynamically defined metastable and unstable regions. We show with this system, which is a poor fit to mean-field assumptions, that the evolution of the structure factor during nucleation is similar to that during spinodal decomposition and reveals no singularity predicted upon crossing the metastability boundary. We introduce two kinetic definitions of the metastability/instability boundary that yield values within approximately 1.5 K, i.e., the boundary appears as an area rather than a line, which is near and above the thermodynamic prediction. Delay times for the appearance of the new phase in the unstable regime are significant, i.e., new-phase growth is hindered by kinetic barriers. While our results agree with predictions of the non-mean-field theories of phase transformations, the experimentally observed behavior is richer than the one envisioned by theory.