Substitutional effect of Cr ions on the properties of Mg–Zn ferrite nanoparticles

The effect of Cr³⁺ substitution in Mg–Zn ferrite, with a chemical formula Mg_0.5Zn_0.5Cr_xFe_2−xO₄ (x=0.0–1.0), synthesized by a sol–gel auto-combustion reaction is presented in this paper. The resultant powders were investigated by various techniques, including X-ray diffractometry (XRD), transmission electron microscopy (TEM), infrared spectroscopy (IR), vibrating sample magnetometry (VSM), and DC resistivity. The XRD pattern revealed that the cubic spinel structure is maintained for the all the compositions. The particle sizes measured from XRD and TEM are in good agreement with each other. The cation distribution suggests that Mg²⁺, Cr³⁺ and Fe³⁺ have strong preference towards octahedral B-site. The theoretical lattice constant and experimental lattice constant match each other very well. The IR analysis supports the presently accepted cation distribution. The saturation magnetization decreases linearly with increasing Cr³⁺ content. Curie temperatures are obtained by the Laoria and AC susceptibility techniques. The dc resistivity has been investigated as a function of temperature and composition.     

Study of the reactions e+e− → ρη, ρπ, φπandφη for total energy ranges between 1.4 and 2.18 GeV

The reactions e⁺e^? → ρη, ρπ, φπ and φη have been studied with the magnetic detector DM1 at DCI in the total energy ranges between 1.4 and 2.18 GeV. The ρη signal is clearly seen. Upper limits for ρπ and φη channels as well as for the OZI forbidden φπ channel.     

Molecular Iodine: An Efficient Catalyst for the Synthesis of Tetrahydrobenzo[b]pyrans

An iodine/DMSO system is introduced as an excellent catalyst in three‐component coupling reactions of tetrahydrobenzo[b]pyran synthesis. The reaction proceeds quickly under very mild reaction conditions.     

Cu(acac)2-Catalyzed N-Arylations of Phenylurea with Aryl Boronic Acid

Cu(acac)₂ activates aryl boronic acids for the reaction with NH₂-phenylurea without additional ligand and heating. The procedure is simple, general, ligand-free, milder than the palladium-catalyzed arylation, and avoids the use of toxic phosphine ligands.     

Study of e+e− → KS0K±π∓ in the 1.4–2.18 GeV energy range: A new observation of an isoscalar vector meson: φ′ (1.65 GeV)

First measurements of the e⁺e^? → K_S⁰K^±π^? reaction in the 1.4–2.18 GeV energy range have been performed with the magnetic detector DM1 at the Orsay storage rings DCI. The cross section is rather large. The production is mainly K¹⁰K⁰ which reveals an interference between isovector and isoscalar amplitudes. These results show again the existence of an isoscalar vector at 1.65 GeV shown to be a φ′ meson.     

One‐Pot Three‐Component Synthesis of 2‐Amino Pyrimidines in Aqueous PEG‐400 at Ambient Temperature

Amino pyrimidines have been synthesized by a one‐pot procedure under environmentally friendly reaction conditions at room temperature. The use of aqueous PEG‐400 circumvents the problems associated with the toxic, hazardous organic solvents and oxidizing agents.     

Electrochemical deposition of cadmium selenide films and their properties: a review

This review gives brief information of experimental conditions employed by different researchers for deposition of cadmium selenide (CdSe) thin films. For the films synthesized at room temperature, films should be annealed and etched to increase the solar cell efficiency. A photoelectrochemical study revealed that values of fill factor and efficiency of CdSe thin films deposited on fluorine-doped tin oxide-coated glass substrates exhibited maximum value compared to the film deposited on titanium and stainless steel substrates. This review will be helpful to researchers entering in field to understand basics about the electrodeposition of CdSe and its development towards next-generation photovoltaics.     

Polyethylene glycol mediated one‐pot three‐component synthesis of new 4‐thiazolidinones

An efficient one‐pot three‐component cyclocondensation of 4‐(p‐toulyl sulfonoxy) benzaldehyde, aryl amines, and mercaptoacetic acid in polyethylene glycol 400 (PEG‐400) was conducted to obtain new 2,3‐disubstituted‐4‐thiazolidinones. This route is economical and ecofriendly. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 23:166–170, 2012; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20766     

Synthesis and Crystal Structures of Aluminum,Gallium and Indium Complexes with Chelating Me2Si(NPh)22– Ligands

The reaction of ECl₃ (E = Al, Ga) with two equivalentsof Li₂Me₂Si(NPh)₂ (in diethyl ether/n‐hexane) leads to the formation of bis‐chelate complexes [Li(OEt₂)₃][E{Me₂Si(NPh)₂}₂] (E = Al ( 1 ), Ga ( 2 )). Compounds 1 and 2 crystallize isotypically in the monoclinic system with a = 1136.42(6), b = 3267.9(1), c = 1360.37(8) pm, β = 94.320(7)° for 1 and a = 1140.88(6), b = 3261.7(2), c = 1360.20(8) pm, β = 94.641(7)° for 2 . Both the compounds display a distorted tetrahedral coordination of the central metal atom to give a spirocyclic EN₄Si₂ core. The Al–N bond lengths are in the range of186.5–186.9 pm and for the Ga–N distances values between 192.3and 193.1 pm are observed. Treatment of InCl₃ with three equivalents of Li₂Me₂Si(NPh)₂ yields the tris‐chelate [{Li(OEt₂)}₃In{Me₂Si(NPh₂)}₃] 3 . Compound 3 crystallizes in the trigonal crystal system , space group R$\bar{3}$ c with a = 1852.4(1), and c = 3300.2(2) pm. The central indium atom is coordinated by threeMe₂Si(NPh)₂^2– ligands in a distorted octahedral arrangement withIn–N bond lengths of 230.8 pm.