A series of dinuclear metallacycles of Mn(II), Co(II), Ni(II), Cu(II) and Cd(II) with 1,8-naphthalene dicarboxylic acid (H
2
NDC) with co-ligand such as 2,2′-bipyridine (bpy) or solvent molecules ...have been synthesized in a refluxed condition. One mononuclear Ni(II) complex has also been synthesized following the same synthetic procedure with NDC, bpy and pyridine. Among them two polymorphic structures have been isolated. The single crystal X-ray structures of all the metallacycles have been described along with Hirshfield surface analysis.
Using a solvothermal method, we have synthesized two coordination polymers of Cu(II). One is a 1D polymer {Cu(bpy)(NDC)(H
2
O)·2H
2
O}
n
(
1
, 1D) formed with 1,8-naphthalene dicarboxylic acid (H
2
...NDC) and 2,2′-bipyridine (bpy) as an auxiliary ligand, while the other is a 2D polymer {Cu
3
(TMA) (Imd)
3
·5H
2
O·2DMF}
n
(
2,
2D) formed with trimellitic acid (H
3
TMA) and imidazole (Imd) as an auxiliary ligand. Both coordination polymers
1
and
2
were formed through an in situ hydrolytic ring opening reaction of 1,8-naphthalic anhydride and trimelitic anhydride with bipyridine and imidazole ligands, respectively. The asymmetric unit of polymer
1
contains asymmetric η
1
binding mode (one of the carboxylate) linking distorted square-pyramidal Cu(NDC)(bpy)(H
2
O)
2+
coordination units. The syn-syn-η
1
:η
1
linear polymeric conformation exist in the 1D coordination polymer with adjacent Cu…Cu distance is 6.849 Å. A chain of cyclic tetrameric water clusters is present between the stacked layers of the 3D supramolecular structure. The formation of the 3D supramolecular structure is guided by various weak interactions such as O–H…O, C–H…O, C–H…π and π…π interactions. The coordination polymer
2
forms 3D supramolecular architecture guided by various weak interactions such as O–H…O, C–H…O and N–H…O interactions. The crystal structures of both coordination polymers have been determined using single crystal X-ray diffraction and their structural features are described.
The agricultural waste dumped onto the land is creating an environmental problem. The conversion of those easily available agro‐wastes into value‐added nano reinforcement materials for biopolymers is ...an alternative method of waste utilization and minimization. In the current study, the red banana peduncle (RBP) waste was used as a precursor in the extraction of carboxylated cellulose nanocrystals (CCNCs) by alkalization, acidified chlorination citric acid hydrolysis, as well as the assessment of its reinforcing capability in polyvinyl alcohol. The characterization of the extracted CCNCs is analyzed through electron microscopy, X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FT‐IR), and Thermogravimetric analysis (TGA), respectively. The CCNCs exhibit a rod‐like shape (235 ± 20 nm length and 17.2 ± 6 nm width) with a high crystallinity of 89.7%, a negative zeta potential (−48 mV), and good thermal resistivity against degradation up to 280 °C. Furthermore, the effects of CCNCs integration on the bionanocomposite films' tensile, optical, bio decomposition, and thermal behavior were examined. The bionanocomposite film with improved physical, functional, thermal and bio decomposition characteristics offers the possibility for active packaging applications.
The experimental results on the ratios of branching fractions R(D)=B(Bover ¯→Dτ^{-}νover ¯_{τ})/B(Bover ¯→Dℓ^{-}νover ¯_{ℓ}) and R(D^{*})=B(Bover ¯→D^{*}τ^{-}νover ¯_{τ})/B(Bover ¯→D^{*}ℓ^{-}νover ...¯_{ℓ}), where ℓ denotes an electron or a muon, show a long-standing discrepancy with the standard model predictions, and might hint at a violation of lepton flavor universality. We report a new simultaneous measurement of R(D) and R(D^{*}), based on a data sample containing 772×10^{6} BBover ¯ events recorded at the ϒ(4S) resonance with the Belle detector at the KEKB e^{+}e^{-} collider. In this analysis the tag-side B meson is reconstructed in a semileptonic decay mode and the signal-side τ is reconstructed in a purely leptonic decay. The measured values are R(D)=0.307±0.037±0.016 and R(D^{*})=0.283±0.018±0.014, where the first uncertainties are statistical and the second are systematic. These results are in agreement with the standard model predictions within 0.2, 1.1, and 0.8 standard deviations for R(D), R(D^{*}), and their combination, respectively. This work constitutes the most precise measurements of R(D) and R(D^{*}) performed to date as well as the first result for R(D) based on a semileptonic tagging method.
We report the first observation of the double strange baryon Ξ(1620)0 in its decay to Ξ−π+ via Ξ+c → Ξ−π+π+ decays based on a 980 fb−1 data sample collected with the Belle detector at the KEKB ...asymmetric-energy e+e− collider. The mass and width are measured to be 1610.4 ± 6.0(stat)+6.1−4.2(syst) MeV /c2 and 59.9 ± 4.8(stat)+2.8−7.1(syst) MeV, respectively. We obtain 4.0σ evidence of the Ξ(1690)0 with the same data sample. These results shed light on the structure of hyperon resonances with strangeness S = −2
Two isostructural mononuclear complexes of lanthanides (Ln = La and Pr) constructed from 1,8-naphthalene dicarboxylate (NDC) and 1,10-phenanthroline (Phen) as auxiliary ligand are reported. Both the ...complexes were formed through an in situ hydrolytic ring opening reaction of 1,8-naphthalic anhydride with Phen ligands. 3D supramolecular structures are observed which are guided by different weak interactions. The crystal structures of both the complexes were determined by single crystal X-ray diffraction. The room temperature photoluminescence studies, carried out in the powder state displayed three noticeable peaks from excited (
3
P
J
;
J
= 2, 1, and 0) to ground state (
3
H
4
) at ~464 nm, 497 nm, and 538 nm, respectively, under UV excitation. Temperature dependent dc susceptibility (χ =
M
/
H
) as a function of temperature is investigated where Pr-complex shows antiferromagnetic behaviour. The Hirshfeld surface analysis of the two complexes is also described.
We report the results of a search for the rare, purely leptonic decay B−→μ−ν¯μ performed with a 711 fb−1 data sample that contains 772×106 BB¯ pairs, collected near the ϒ(4S) resonance with the ...Belle detector at the KEKB asymmetric-energy e+e− collider. The signal events are selected based on the presence of a high momentum muon and the topology of the rest of the event showing properties of a generic B-meson decay, as well as the missing energy and momentum being consistent with the hypothesis of a neutrino from the signal decay. We find a 2.4 standard deviation excess above background including systematic uncertainties, which corresponds to a branching fraction of B(B−→μ−ν¯μ)=(6.46±2.22±1.60)×10−7 or a frequentist 90% confidence level interval on the B−→μ−ν¯μ branching fraction of 2.9,10.7×10−7.
Current research issues in the development of efficient analysis models and their efficient numerical implementation for smart piezoelectric laminated structures are discussed in this paper. The ...improved zigzag theories with a layerwise quadratic variation of electric potential have emerged as the best compromise between accuracy and cost for hybrid composite, sandwich and FGM beams and plates. The concept of associating surface potentials to electric nodes and internal potentials to physical nodes is very effective in modeling the equipotential electroded surfaces. Unified formulations for shear and extension mode actuation, and modeling of piezoelectric composite actuators and sensors are discussed. Future challenge lies in developing efficient theories capable of predicting the interlaminar transverse shear stresses in hybrid laminates directly from the constitutive equations.
We report the first observation of the spontaneous polarization of Λ and Λover ¯ hyperons transverse to the production plane in e^{+}e^{-} annihilation, which is attributed to the effect arising from ...a polarizing fragmentation function. For inclusive Λ/Λover ¯ production, we also report results with subtracted feed-down contributions from Σ^{0} and charm. This measurement uses a dataset of 800.4 fb^{-1} collected by the Belle experiment at or near a center-of-mass energy of 10.58 GeV. We observe a significant polarization that rises with the fractional energy carried by the Λ/Λover ¯ hyperon.
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