Compilation of directly measured nuclear spins of ground states and long-lived isomers

A compilation of the nuclear spins of ground and isomeric states measured by direct methods is presented. The first compilation of direct measurements of nuclear spins and moments was published in 1976 (G. H. Fuller, J. Phys. Chem. Ref. Data 5, 835, (1976)) with literature covered up to 1974. To our knowledge, the present work is the first such compilation since then. It is anticipated that the area of direct spin measurement will continue to expand using the state-of-the-art radioactive ion-beam and laser techniques. Literature cutoff date for the present compilation is February 2013. It is intended that the present compilation will be kept updated in a timely manner.     

Synthesis of 3D cubic of Eu3+/Cu2O with clover-like faces nanostructures and their application as an electrochemical sensor for determination of antiretroviral drug nevirapine

In this experiment, an original three-dimensional (3D) cubic of europium (Eu) ³⁺/cuprous oxide (Cu₂O) with clover-like face-centered nanostructures (Eu³⁺/Cu₂O CLFNs) was successfully synthesized to determine nevirapine (C₁₅H₁₄N₄O), using electrochemical methods. The surface morphology of the Ns was correspondingly identified through different techniques, including energy dispersive X-ray spectroscopy (EDX), X-ray powder diffraction (XRD), and scanning electron microscopy (SEM). In this sense, the synergistic influence of the Eu³⁺/Cu₂O CLFNs enhanced the electrocatalytic capability of the electrode via a modified glassy carbon (GC) and raised the active site. Employing various approaches, the modified electrode was then analyzed through cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Moreover, kinetic parameters and electrochemical ones were estimated by means of voltammetric methods. For the determination of nevirapine applying the Eu³⁺/Cu₂O CLFNs/GC electrode (GCE), differential pulse voltammetry (DPV) was further utilized. Under optimized conditions, the range of linear responses was between 0.01 and 750.0 μM with the limit of detection (LOD) of 3.6 nM, whereas the recommended sensor sensitivity was equal to 0.1244 μA/μM. The response time of approximately 3.5 min and the reproducibility (inter- and intra-electrode reproducibility of 2.26% and 1.51%, respectively) were subsequently achieved. It was concluded that sensors have been thus far exploited to determine nevirapine in real samples with favorable outcomes, indicating that electrocatalysis modifier can be assumed as one of appropriate catalysts.     

Fabrication and characterization of exfoliated chitosan–gelatin–montmorillonite nanocomposite nanofibers

Polymeric nanofibers as one of the most known nanotechnology products have huge potential applications in many fields due to their high aspect ratio and porosity, being capable of formation of three-dimensional structures and having great mechanical and biological properties. Chitosan is a natural abundant polymer which has attracted huge interests in biomedical and biological industries due to its biocompatible, biodegradable, and non-toxicity properties. However, electrospinning of chitosan is found to be a great challenge, blending it with other polymers such as gelatin was explored as means to improve the morphological deficiencies of chitosan nanofibers and facilitate its electrospinnability. On the other hand, montmorillonite (MMT) has been attracted great attention due to its remarkable improvement in properties of polymeric composites nanofibers. The main objective of this work was on effect of concretion of gelatin–chitosan blends and MMT on morphology of resulted nanocomposite nanofibers. The x-ray diffraction data demonstrated the exfoliation of MMT layers. The morphology of electrospun chiosan–gelatin–MMT composite nanofibers was characterized using scanning electron microscope (SEM). The miscibility of blend was determined using SEM and Fourier transform infrared spectrometer/attenuated total reflectance.     

Beyond Gold: Spin‐Coated Ti3C2‐Based MXene Photodetectors

2D transition metal carbides, known as MXenes, are transparent when the samples are thin enough. They are also excellent electrical conductors with metal‐like carrier concentrations. Herein, these characteristics are exploited to replace gold (Au) in GaAs photodetectors. By simply spin‐coating transparent Ti₃C₂‐based MXene electrodes from aqueous suspensions onto GaAs patterned with a photoresist and lifted off with acetone, photodetectors that outperform more standard Au electrodes are fabricated. Both the Au‐ and MXene‐based devices show rectifying contacts with comparable Schottky barrier heights and internal electric fields. The latter, however, exhibit significantly higher responsivities and quantum efficiencies, with similar dark currents, hence showing better dynamic range and detectivity, and similar sub‐nanosecond response speeds compared to the Au‐based devices. The simple fabrication process is readily integratable into microelectronic, photonic‐integrated circuits and silicon photonics processes, with a wide range of applications from optical sensing to light detection and ranging and telecommunications.