Carbon nanotubeben cuprous oxide composite based pressure sensors

In this paper, we present the design, the fabrication, and the experimental results of carbon nanotube (CNT) and Cu₂O composite based pressure sensors. The pressed tablets of the CNT-Cu₂O composite are fabricated at a pressure of 353 MPa. The diameters of the multiwalled nanotubes (MWNTs) are between 10 nm and 30 nm. The sizes of the Cu₂O micro particles are in the range of 3-4 μm. The average diameter and the average thickness of the pressed tablets are 10 mm and 4.0 mm, respectively. In order to make low resistance electric contacts, the two sides of the pressed tablet are covered by silver pastes. The direct current resistance of the pressure sensor decreases by 3.3 ×as the pressure increases up to 37 kN/m². The simulation result of the resistance-pressure relationship is in good agreement with the experimental result within a variation of ± 2%.     

An Unusual Diorganotin Bis-carboxylate Structure: catena-{(μ2-2-methyl-3,5-dinitrobenzoato-O,O′)dibutyltin(IV)}

Abstract  

The structure of n-Bu₂Sn(2-methyl-3,5-dinitrobenzoato)₂ (1) presents a rare structural motif for compounds with the general formula R ₂Sn(O₂CR′)₂ which almost exclusively adopt skew-trapezoidal bipyramidal geometries. By contrast, the structure of (1) is polymeric with the polymer backbone comprising eight-membered {SnOCO}₂ rings linked at the pivotal tin atoms. The coordination geometry is octahedral trans-C₂O₄. The relationship between structural motifs for R ₂Sn(O₂CR′)₂ is discussed. Compound (1) crystallizes in the monoclinic space group P2₁/c with a = 5.0114(2) ?, b = 13.7120(5) ?, c = 19.5956(7) ?, β = 91.385(2)o, and Z = 2.     

Single-cell protein analysis of a single mouse embryo by two-dimensional capillary electrophoresis

The characterization of protein expression from a single-cell mouse embryo using two-dimensional capillary electrophoresis (2D-CE) is described. These zygotes were obtained from Hsf1 gene knockout mice. Single zygotes were lysed off-column and proteins were fluorescently labeled using the fluorogenic dye 3-(2-furoyl)quinoline-2-carboxaldehyde (FQ). After injection, analytes were separated first according to molecular weight using capillary sieving electrophoresis (CSE) and then by micellar electrokinetic capillary chromatography (MEKC) to obtain protein expression fingerprints. Analytes were detected in a sheath flow cuvette using laser-induced fluorescence. In a 1-h 2D-CE separation, over 100 components were resolved with a spot capacity of 380.     

Synthesis,crystal structures and catalytic activities of new palladium(II)–bis(oxazoline) complexes

Palladium–bis(oxazoline) complexes (Pd-BOX-A and Pd-BOX-B) were synthesized and characterized by ¹H, ¹³C NMR, IR and elemental analysis. The molecular structures of the complexes were confirmed by single-crystal X-ray analysis. In both cases, the palladium center is coordinated by the nitrogen atoms of the two oxazoline rings and two chloride ligands in a distorted square planar geometry. Despite the fact that the bis(oxazoline) ligand is achiral, the asymmetrical substitution on the phenyl spacer and the rigid backbone of the complex Pd-BOX-A induce inherent chirality and the compound crystallizes as a racemic mixture. Both complexes were found to be highly effective catalysts for Suzuki–Miyaura, Mizoroki–Heck and Sonogashira cross-coupling reactions. They also show excellent catalytic activities toward carbonylative coupling reactions.     

Surface-engineering strategies for g-C3N4 as efficient visible-light photocatalyst

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Mercury(II) cyanide complexes of thioureas and the crystal structure of [(N-methylthiourea)2 Hg(CN)2]

Mercury(II) cyanide complexes of thioureas (Tu), N-methylthiourea (MeTu), and N,N′-dimethylthiourea (DmTu)) have been prepared and characterized by IR and NMR (¹H and ¹³C) spectroscopy, and the crystal structure of one of them was determined by X-ray crystallography. An upfield shift in ¹³C NMR and downfield shifts in ¹H NMR are consistent with the sulfur coordination to mercury(II). The appearance of a band around 2200 cm^?1 in IR and a resonance around 145 ppm in ¹³C NMR indicates the binding of cyanide to mercury(II). The NMR data show that the [(Thione)₂Hg(CN)₂] complexes are stable in solution and undergo no redistribution reactions. In the crystal structure of the title complex, mercury atom is coordinated to two thione sulfur atoms of MeTu and to two cyanide carbon atoms in a distorted tetrahedral mode with the bond angles in the range of 90.2(2)°–169.3(3)°.     

PIKfyve,a Class III PI Kinase,Is the Target of the Small Molecular IL-12/IL-23 Inhibitor Apilimod and a Player in Toll-like Receptor Signaling

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Autler-Townes triplet spectroscopy: An analytical approach

In Ref. [Opt. Commun. 273, 464-472 (2007)] we studied Autler-Townes triplet spectrum. The presented results were not easy to display in readable and transparent form because the operating physical mechanism is hidden by the algebraic complexity. Here we present analytical results in a very simple and interpretable form. These results enable us to get a new insight into the interference mechanism in a quiet clear manner. We have given a new dimension to the problem in calculating the emission spectrum by state vector method. New estimates are given to measure the spectroscopic parameters in analytical fashion. The interference mechanism in the excited three decaying dressed state is effectively explored which splits the single Lorentzian peak to three spectral components due to two dark lines. The width of each spectral component can be narrowed to up to 0.05Γ.     

Multipotent Cholinesterase Inhibitors for the Treatment of Alzheimer’s Disease: Synthesis,Biological Analysis and Molecular Docking Study of Benzimidazole-Based Thiazole Derivatives

Twenty-four analogues of benzimidazole-based thiazoles (1–24) were synthesized and assessed for their in vitro acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitory potential. All analogues were found to exhibit good inhibitory potential against cholinesterase enzymes, having IC₅₀ values in the ranges of 0.10 ± 0.05 to 11.10 ± 0.30 µM (for AChE) and 0.20 ± 0.050 µM to 14.20 ± 0.10 µM (for BuChE) as compared to the standard drug Donepezil (IC₅₀ = 2.16 ± 0.12 and 4.5 ± 0.11 µM, respectively). Among the series, analogues 16 and 21 were found to be the most potent inhibitors of AChE and BuChE enzymes. The number (s), types, electron-donating or -withdrawing effects and position of the substituent(s) on the both phenyl rings B & C were the primary determinants of the structure-activity relationship (SAR). In order to understand how the most active derivatives interact with the amino acids in the active site of the enzyme, molecular docking studies were conducted. The results obtained supported the experimental data. Additionally, the structures of all newly synthesized compounds were elucidated by using several spectroscopic methods like ¹³C-NMR, ¹H-NMR and HR EIMS.     

Analytical substrate flux approximation for the Monod boundary value problem

We present an analytical approximation for the diffusive flux of a substrate into a reactive layer, in which the substrate is degraded according to Monod kinetics. This problem is described by a nonlinear two-point boundary value problem. The approximation is derived based on a Homotopy Analysis Method idea and verified computationally, by comparison against a numerical solution of the problem. The analytical approximation is easy to evaluate and depends only on model parameters.