Static Charge Susceptibility in the <Emphasis Type="Italic">t-J-V</Emphasis> Model

We describe the static charge susceptibility and correlation function of the charge density in the twodimensional t-J-V model based on the method of equations of motion for the relaxation functions of the Hubbard operators. We obtain the dependence of the susceptibility and correlation function on the hole concentration and temperature. Charge density waves can develop if the intersite Coulomb interaction is sufficiently strong.     

New fabrication approach to develop a high birefringence photo-crosslinked film based on a sulfur-containing liquid crystalline molecule with large temperature dependence of birefringence

ABSTRACT

We present a new fabrication approach to achieve a high birefringence film by means of photopolymerization based on an alkylthio-containing rod-like liquid crystalline molecule exhibiting large temperature dependence of birefringence. We designed a new reactive mesogen having alkylthio linkages (BPM–S). It was found that BPM–S had a larger increment of birefringence with decreasing temperature, relative to commercially available alkoxy analog LC242. This result could be thought to be due to enhanced intermolecular attractive interaction for an alkylthio mesogen implied by the proximity of laterally neighboring molecules and cybotactic nematic tendency based on wide-angle X-ray measurement. The uniaxially-aligned photo-polymerized film for BPM–S showed higher birefringence than that for LC 242.     

Repdigits as sums of three Pell numbers

In this paper, all base 10 repdigits expressible as sums of three Pell numbers are found.     

Redox-Induced Modulation of Exchange Interaction in a High-Spin Ground-State Diradical/Triradical System

A triplet ground-state diradical molecule, bis(nitronyl nitroxide)-substituted diphenyldihydrophenazine ( 1 ^..), that can be converted into a one-electron oxidized species, 1 ^{… +} , in the quartet ground state has been developed. Surprisingly, these species, 1 ^.. and 1 ^{… +} , can be used under ambient conditions because they are reasonably stable under aerobic conditions, even in solution. The temperature-dependent magnetic susceptibilities reveal that 1 ^.. and 1 ^{… +} are in the triplet state, with a weak exchange interaction (J₁/k_B = +3.1 K) and quartet ground state with a strong exchange interaction (J₂/k_B = +160 K), respectively. The interconversion between the neutral and one-electron oxidized species can be realized through electrochemical reactions. Significantly different absorption bands in the near-IR region newly appeared in the electronic spectra acquired during electrochemical oxidation/reduction.     

A cell-permeable green fluorescent probe for dsDNA

The sensitive and selective detection of nucleic acids is important for basic research and many applied fields. Herein, a novel green DEAB-TO-1 was designed and synthesized. DEAB-TO-1 shows significant fluorescence enhancement (800-fold) when bound to ctDNA and a distinct selectivity for dsDNA over RNA (5.9 times). Moreover, the limit of detection is 0.57 ng/mL. It is live-cell-permeant DNA intecalator, indicating a promising candidate for nucleus-specific imaging and a good counter-stain compatibility with other dyes.     

Usage of deep eutectic solvents for the digestion and ultrasound-assisted liquid phase microextraction of copper in liver samples

In this study, we used deep eutectic solvents for digestion and ultrasound-assisted emulsification liquid phase microextraction (UA-ELPME) of copper in liver samples. Different types of DESs were prepared for digestion and microextraction steps. DESs consisting of lactic acid and choline chloride for the digestion step and DESs consisting of tetrabuthylamonium chloride and decanoic acid for ultrasound-assisted emulsification liquid phase microextraction were used in this method. The liver samples were digested by using DES-based digestion method. After digestion step, Cu(II) ions in aqueous phase were complexed with sodium dimethyl dithiocarbamate (NaDMDTC) and the obtained hydrophobic complex was extracted to tetrabuthylamonium chloride-decanoic acid DES phase. A microsample injection system coupled with flame atomic absorption spectrometer (MS-FAAS) was used in the detection of copper. LOD, LOQ, PF and % RSD were determined as 4.00, 13.2 µg L^??1, 10 and 3.2%, respectively. The proposed microextraction procedure was successfully applied to copper contents of the liver samples.