CVD grown 2D MoS2 layers: A photoluminescence and fluorescence lifetime imaging study

In this letter, we report on the fluorescence lifetime imaging and accompanying photoluminescence properties of a chemical vapour deposition (CVD) grown atomically thin material, MoS₂. µ‐Raman, µ‐photoluminescence (PL) and fluorescence lifetime imaging microscopy (FLIM) are utilized to probe the fluorescence lifetime and photoluminescence properties of individual flakes of MoS₂ films. Usage of these three techniques allows identification of the grown layers, grain boundaries, structural defects and their relative effects on the PL and fluorescence lifetime spectra. Our investigation on individual monolayer flakes reveals a clear increase of the fluorescence lifetime from 0.3 ns to 0.45 ns at the edges with respect to interior region. On the other hand, investigation of the film layer reveals quenching of PL intensity and lifetime at the grain boundaries. These results could be important for applications where the activity of edges is important such as in photocatalytic water splitting. Finally, it has been demonstrated that PL mapping and FLIM are viable techniques for the investigation of the grain‐boundaries.

     

Diverse Reactivity of an Electrophilic Phosphasilene towards Anionic Nucleophiles: Substitution or Metal–Amino Exchange

The reaction of MesLi (Mes=2,4,6‐trimethylphenyl) with the electrophilic phosphasilene R₂(NMe₂)Si‐RSi=PNMe₂ ( 2 , R=Tip=2,4,6‐triisopropylphenyl) cleanly affords R₂(NMe₂)Si‐RSi=PMes and thus provides the first example of a substitution reaction at an unperturbed Si=P bond. In toluene, the reaction of 2 with lithium disilenide, R₂Si=Si(R)Li ( 1 ), apparently proceeds via an initial nucleophilic substitution step as well (as suggested by DFT calculations), but affords a saturated bicyclo[1.1.0]butane analogue as the final product, which was further characterized as its Fe(CO)₄ complex. In contrast, in 1,2‐dimethoxyethane the reaction of 1 with 2 results in an unprecedented metal–amino exchange reaction.     

Electroanalytical Investigation and Simultaneous Determination of Etodolac and Thiocolchicoside at a Non-modified Glassy Carbon Electrode in Anionic Surfactant Media

In this study, a differential pulse voltammetry method was designed for the simultaneous determination of etodolac and thiocolchicoside in a tablet dosage form. This method is a sensitive, costless and reproducible one initially designed for the simultaneous determination of etodolac and thiocolchicoside using bare/unmodified glassy carbon electrode in the presence of sodium dodecyl sulfate. At optimized conditions, the method showed linear responses with etodolac and thiocolchicoside concentration in the range of 1 μM to 80 μM. The limits of detection and quantification were calculated as 0.11 μM and 0.38 μM for etodolac and 0.20 μM and 0.67 μM for thiocolchicoside, respectively.     

Liver schwannoma: findings on MRI

Magnetic resonance imaging features of benign liver schwannoma in a 52-year-old woman are described. An oval shaped, 4.4×3.6×2.9-cm lesion was located in Segment 7 of the right hepatic lobe. The lesion was hypointense on T₁-weighted images and mixed hypo- and hyperintense on T₂-weighted images. On serial contrast-enhanced images, the lesion revealed gradually increasing centrilobular enhancement. The tumor was surgically removed thereafter.     

2‐[(2‐Hydro­xy‐4‐nitro­phenyl)­amino­methyl­ene]­cyclo­hexa‐3,5‐dien‐1(2H)‐one

The title compound, C₁₃H₁₀N₂O₄, adopts the keto–amine tautomeric form and displays an intramolecular N—H⋯O [N⋯O = 2.579 (2) Å] and three intermolecular O—H⋯O [O⋯O = 2.561 (2) Å] and C—H⋯O [C⋯O = 3.274 (2) and 3.318 (2) Å] hydrogen bonds. The keto–amine structure is favoured by through‐mol­ecule conjugation between the hydroxy O atom and imine N atom. The dihedral angle between the planes of the two aromatic rings is 10.79 (4)°.     

Cellulose based electrospun nanofilters: perspectives on tannery effluent waste water treatment

Cellulose - Development of nanofilters with the ability to remove toxic metal ions from effluent wastewater will be of immense help to the leather industry. In this study, fibrous nanofilter (FNF)...     

Hasse–Weil bound for additive cyclic codes

We obtain a bound on the minimum distance of additive cyclic codes via the number of rational points on certain algebraic curves over finite fields. This is an extension of the analogous bound in the case of classical cyclic codes. Our result is the only general bound on such codes aside from Bierbrauer’s BCH bound. We compare our bounds’ performance against the BCH bound for additive cyclic codes in a special case and provide examples where it yields better results.     

Carbon nanoparticle modified screen printed carbon electrode as a disposable electrochemical immunosensor strip for the detection of Japanese encephalitis virus

The authors describe a disposable electrochemical immunosensor strip for the detection of the Japanese encephalitis virus (JEV). The assay is based on the use of a screen printed carbon electrode (SPCE) modified with carbon nanoparticles (CNPs) that were prepared from starch nanoparticles and deposited on the SPCE working electrode whose surface was functionalized with 3-aminopropyl triethoxysilane. Next, antibody of JEV was immobilized on the surfaces of the CNPs. The analytical performance of immunosensor strip was characterized using cyclic voltammetry (with hexacyanoferrate as the redox probe) and electrochemical impedance spectroscopy. The deposition of CNPs enhances the electron transfer kinetics and current intensity of the SPCE by 63% compared to an unmodified SPCE. Under optimized conditions, the calibration plot is linear within the 5–20 ng·mL^?1 JEV concentration range, the limit of detection being 2 ng·mL^?1 (at an S/N ratio of 3), and the assay time is 20 min. This immunosensor strip was successfully applied to the detection of JEV in human serum samples. It represents a cost-effective alternative to conventional diagnostic tests for JEV.

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Graphical abstract A disposable carbon nanoparticles modified screen printed carbon electrode (SPCE) immunosensor strip for Japanese encephalitis virus (JEV) detection is described. A limit of detection of 2 ng·mL^?1 and an assay time of 20 min were achieved.