Λb→Λ(→pπ−)ℓ+ℓ−\Lambda_b\rightarrow \Lambda(\to p \pi^-) \ell^+\ell^- as probe of CP-violating New Physics

We investigate the possible sizes of all the CP-violating asymmetries offered by the angular distribution of rare decay $\Lambda_b\rightarrow \Lambda(\to p \pi^-) \ell^+\ell^-$ in the Standard Model and new physics scenarios motivated by the recent $b\to s \ell^+\ell^-$ anomalies. We work in a model-independent effective theory framework and discuss the sensitivity of CP asymmetries to new ${O}_{9,10}$ operators and their chirality flipped counterparts. We find that the size of many of the CP asymmetries can be at the level of few percent in new physics scenarios consistent with current $b\to s\ell^+\ell^-$ data at level of $1\sigma$. We emphasize that measurements of these CP asymmetries can be used to discriminate different new physics scenarios in $b\to s \ell^+\ell^-$.Comment: 27 pages, 4 captioned figures; v2: fixed typos and added new reference

Carboxyl functionalized graphene oxide based electrochemical sensor for detection of dopamine in presence of ascorbic acid, uric acid and synthetic cerebrospinal fluid

365-369Dopamine is an important neurotransmitter and plays a vital role in the proper functioning of human metabolism. Therefore, fabrication of a sensitive sensor for the detection of dopamine is crucial. The work reports detection of dopamine in presence of interfering ascorbic acid, uric acid, Na+, K+, Ca2+, urea and glucose. The linear range for the detection of dopamine is observed from 1.07×10-4 M to 2.19×10-4 M in presence of 1.00×10-3 M ascorbic acid and 1.00×10-3 M uric acid. The detection limit is estimated to be 1.46×10-8 M

(E)-(4-Methoxyphenyl)-N-(4H-1,2,4-triazol-4-yl) methanimine: Solvent driven single molecule triple fluorescent “on” sensor for Cu2+, Cd2+ and Hg2+

213-217A single molecule, (E)-(4-methoxyphenyl)-N-(4H-1,2,4-triazol-4-yl) methanimine (Metho-tria-imine), can detect Cu2+, Cd2+ or Hg2+ depending on whether the solvent is H2O, CH3CN or C2H5OH respectively by fluorescence “on” mode. The enhancement in fluorescence intensity is found to be ca. 13 times for Cu2+, 70 times for Cd2+ and 57 times for Hg2+. The metal ions - Al3+, Co2+, K+, Li+, Mg2+, Mn2+, Na+, Ni2+, Pb2+, Zn2+ (along with two metal ions out of Cu2+, Cd2+ and Hg2+ for which the sensor is not effective) do not interfere. The plot of absorbance versus metal ion concentration was sigmoidal for Cu2+ and Cd2+ and linear for Hg2+ which indicates formation of dimeric complexes in solution for Cu2+ and Cd2+. DFT studies showed metal-metal bonding in case of Metho-tria-imine forming complexes with Cu2+ and Cd2+ and hence dimeric complexes with highest binding energy for Cu2+ in H2O, Cd2+ in CH3CN, Hg2+ in C2H5OH. The detection limits are found to be 1.9×10-8 M, 7.0×10-7 M and 6.9×10-8 M respectively and Metho-tria-imine is reversible with respect to EDTA2- for all the three metal ion

(E)-(4-Methoxyphenyl)-N-(4H-1,2,4-triazol-4-yl) methanimine: Solvent driven single molecule triple fluorescent “on” sensor for Cu2+, Cd2+ and Hg2+

A single molecule, (E)-(4-methoxyphenyl)-N-(4H-1,2,4-triazol-4-yl) methanimine (Metho-tria-imine), can detect Cu2+, Cd2+ or Hg2+ depending on whether the solvent is H2O, CH3CN or C2H5OH respectively by fluorescence “on” mode. The enhancement in fluorescence intensity is found to be ca. 13 times for Cu2+, 70 times for Cd2+ and 57 times for Hg2+. The metal ions - Al3+, Co2+, K+, Li+, Mg2+, Mn2+, Na+, Ni2+, Pb2+, Zn2+ (along with two metal ions out of Cu2+, Cd2+ and Hg2+ for which the sensor is not effective) do not interfere. The plot of absorbance versus metal ion concentration was sigmoidal for Cu2+ and Cd2+ and linear for Hg2+ which indicates formation of dimeric complexes in solution for Cu2+ and Cd2+. DFT studies showed metal-metal bonding in case of Metho-tria-imine forming complexes with Cu2+ and Cd2+ and hence dimeric complexes with highest binding energy for Cu2+ in H2O, Cd2+ in CH3CN, Hg2+ in C2H5OH. The detection limits are found to be 1.9×10-8 M, 7.0×10-7 M and 6.9×10-8 M respectively and Metho-tria-imine is reversible with respect to EDTA2- for all the three metal ion

New fluorescent chemodosimeter for Cu²⁺ based on Schiff base derived from 1-naphthylamine and 2-chlorobenzaldehyde

1391-1396<span style="letter-spacing:-.2pt;mso-ansi-language: PT-BR" lang="PT-BR">On condensation of 1-naphthylamine with 2-chlorobenzaldehyde, the Schiff base (Z)-N-(2-chlorobenzylidene)naphthalene-1-amine (L) is formed which shows moderate fluorescence. L on interaction with Cu2+ hydrolyses back into fluorescent 1-naphthylamine and hence acts as fluorescent chemodosimeter for Cu2+ by “off-on” mode with an ca. 18 times enhancement in fluorescent intensity (detection limit is 10-5 M). The other hydrolysed product, 2-chlorobenzaldehyde, forms a tris chelate complex with Cu2+, as shown by UV/visible spectroscopy and cyclic voltammetry. The metal ions, Na+, K+, Ca2+, Mn2+, Fe2+, Co2+, Ni2+, Cd2+, Hg2+, Pb2+ and Ag+, do not interfere while in the case of Zn2+, moderate interference is observed. </span

2,7-Diferrocenyl-3,6-diazaocta-2,6-diene: A highly selective dual fluorescent sensor for Zn²⁺and Ag⁺and electrochemical sensor for Zn²⁺

816-8202,7-Diferrocenyl-3,6-diazaocta-2,6-diene (DFDD), obtained by condensation reaction of acetylferrocene and ethylenediamine, exhibits Zn2+ ion-induced enhancement of fluorescence intensity and Ag+ ion-induced quenching of fluorescence intensity. The Zn2+ ion shifts the redox potential of DFDD from +0.660 V ± 0.005 V to + 0.615 ± 0.005 V as observed by cyclic voltammetry and square wave voltammetry. Ca2+, Mg2+, Mn2+, Fe2+, Co2+, Ni2+, Cu2+, Cd2+, Pb2+ and Hg2+ have very little effect on fluorescence intensity of DFDD. These metal ions together with Ag+ ion have no effect on the electrochemistry of DFDD. Both, fluorescence and UV-visible spectroscopic data show a 1:1 interaction between DFDD and Zn2+ with binding constant 75 M -1. The applicability of DFDD as fluorescence sensor for Zn2+ ion has been shown in its estimation in commercial tablets