The alcoholic extract at a concentration of 300 mg/mL showed potent activity on comparing with the standard drug diclofenac sodium.

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An easy and convenient method for the synthesis of cobalt and magnesium ferrite nanoparticles is demonstrated using liquid foams as templates. The foam is formed from an aqueous mixture of an anionic surfactant and the desired metal ions, where the metal ions are electrostatically entrapped by the surfactant at the thin borders between the foam bubbles and their junctions. The hydrolysis is carried out using alkali resulting in the formation of desired nanoparticles, with the foam playing the role of a template. However, in the formation of ferrites with the formula MFe(2)O(4), where the metal ion and iron possess oxidation states of +2 and +3, respectively, forming a foam from a 1:2 mixture of the desired ionic solutions would lead to a foam composition at variance with the original solution mixture because of greater electrostatic binding of ions possessing a greater charge with the surfactant. In our procedure, we circumvent this problem by preparing the foam from a 1:2 mixture of M(2+) and Fe(2+) ions and then utilizing the in situ conversion of Fe(2+) to Fe(3+) under basic conditions inside the foam matrix to get the desired composition of the metal ions with the required oxidation states. The fact that we could prepare both CoFe(2)O(4) and MgFe(2)O(4) particles shows the vast scope of this method for making even multicomponent oxides. The magnetic nanoparticles thus obtained exhibit a good crystalline nature and are characterized by superparamagnetic properties. The magnetic features observed for CoFe(2)O(4) and MgFe(2)O(4) nanoparticles are well in accordance with the expected behaviors, with CoFe(2)O(4) particles showing higher blocking temperatures and larger coercivities. These features can easily be explained by the contribution of Co(2+) sites to the magnetocrystalline anisotropy and the absence of the same from the Mg(2+) ions.

Studies on a large number of compositions among the ferromagnetic self-doped manganites, La1−xMnO3, show that the ferromagnetic Curie temperature increases with x and reaches a maximum value for x = 1/7. Tc remains independent of x for x ≥ 1/7 and the maximum value of the magnetization is obtained for x = 1/8. The presence of a second phase, due to Mn3O4, whose contribution increases with x, is observed in the powder x-ray diffraction patterns for x > 1/8 and the lattice parameters remain independent of x for x > 1/8. The results indicate that the limiting value of x or the extent of self-doping possible in La1−xMnO3 is x = 1/8.

The tellurides Tl(10-x)La(x)Te(6) were synthesized from the elements in stoichiometric ratios at 873 K, followed by slow cooling. These materials are substitution variants of Tl(5)Te(3), crystallizing in space group I4/mcm, with lattice dimensions of a = 8.9220(4) Å, c = 13.156(1) Å, V = 1047.2(1) Å(3), for x = 1 (Z = 2). Increasing the La content occurs with an increase in the unit cell volume and the c axis, but a decrease of the a axis. Tl(5)Te(3) is a metallic compound, while Tl(9)LaTe(6) was calculated to be semiconducting. Correspondingly, the Seebeck coefficient increases with increasing x, while the electrical and thermal conductivity both decrease. The highest thermoelectric figure-of-merit determined thus far is 0.21 at 581 K for cold-pressed Tl(9)LaTe(6).

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BaCu6–xSTe6 and BaCu6–xSe1–yTe6+y were synthesized from the elements at 663 K. These chalcogenides adopt a new structure type, cubic space group Pm$\bar {3}$, with a = 6.9680(2) Å in the case of BaCu5.93SeTe6. Therein, the Cu atoms form cubic clusters, centered by Se atoms, where statistically 2.07 corners are unoccupied. All Te atoms are part of Te22– dumbbells, leading to a charge‐balanced formula when x = 0: Ba2+(Cu+)6Se2–(Te22–)3. While Te atoms can be incorporated on the Se site, no evidence was found for the ability of Se atoms to replace Te in the Te22– pairs. Band structure calculations on different BaCu6SeTe6 models revealed a very small band gap at the Fermi level; all these chalcogenides with x > 0 should thus be p‐doped semiconductors, which we experimentally confirmed for BaCu5.7Se0.6Te6.4.