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A polycrystalline sample of ([Bi.sub.0.5][K.sub.0.5])([Fe.sub.0.5][Nb.sub.0.5])[O.sub.3] was prepared using a mixed oxide at 1000°C. The preliminary structural analysis using X-ray diffraction data of the compound indicates the formation of a single-phase rhombohedral structure similar to that of parent BiFe[O.sub.3]. Microstructural and elemental analysis using a scanning electron micrograph and energy-dispersive X-ray spectroscopy, respectively, were carried out at room temperature with higher magnification exhibiting a uniform distribution of grains and stoichiometry. The appearance of hysteresis loops (P-E) confirms the existence of ferroelectricity of the sample with a high remnant polarization of (2[P.sub.r]) 17.76 µC [cm.sup.-2]. Using impedance spectroscopy, the electrical properties of the material were investigated at a wide range of temperature (25-500°C) and frequencies (1 kHz-1 MHz) suggesting dielectric non-Debye-type relaxation in the material. The nature of the Nyquist plot (Z' ~ Z') shows the dominance of the grain contribution in the impedance. The bulk resistance of the compound decreases with increasing temperature, like that of a semiconductor, which shows a negative temperature coefficient of resistance (NTCR) behavior. The frequency dependence of AC conductivity suggests that that the material obeys Jonscher's power law. Magnetic hysteresis (M-H) loop shows very weak ferromagnetic behavior at room temperature. PACS Nos.: 75.85+t, 61.10.Nz, 77.22.-d, 72.80.Le. Nous preparons un echantillon poly-cristallin de ([Bi.sub.0.5][K.sub.0.5])([Fe.sub.0.5][Nb.sub.0.5])[O.sub.3] par melange d'oxydes a 1000°C. L'analyse preliminaire de structure a l'aide de la diffraction X indique la formation d'une structure rhomboedre a phase unique, similaire a celle du parent BiFe[O.sub.3]. L'analyse micro-structurelle et fondamentale utilisant les techniques SEM et EDAX de micrographie electronique a balayage, a la temperature de la piece et plus haute magnification, montre une distribution uniforme des grains et de la strechiometrie. L'apparition de boucles d'hysterese (P-E) confirme la ferroelectricite de l'echantillon avec une haute polarisation remanente de (2[P.sub.r]) 17.76 µC [cm.sup.-2]. L'utilisation d'une technique de spectroscopie d'impedance permet une etude des proprietes electriques de l'echantillon, sur de larges domaines de temperature (25-500°C) et de frequence (1 kHz-1 MHz), qui suggere une relaxation dielectrique dans le materiel qui n'est pas du type Debye. Le graphique (Z' ~ Z') de Nyquist montre la dominance de la domination du grain dans l'impedance. La resistance en volume de l'echantillon decroit lorsqu'augmente la temperature, de faxon similaire a un semi-conducteur avec un coefficient thermique de resistance negatif. La dependance en frequence de la conductivite ac suggere que le materiel obeit a une loi de puissance de Joncher. La boucle d'hysterese (M-H) est caracteristique d'un tres faible ferromagnetisme a la temperature de la piece. [Traduit par le Redaction], 1. Introduction Multiferroics exhibit multiple ferroic properties (i.e., ferroelectricity and ferromagnetism in a structurally distorted system), which allow mutual control of electric polarization with magnetic field or controlling magnetization by [...]

The traditional medicine of India, Ayurveda, discusses the use of herbals for beauty, which is based on conventional wisdom. An effective and powerful technology in the cosmetics field is herbal cosmetics. There is nothing more ancient than humanity and civilization than the concept of beauty and cosmetics. Therefore, many of them use beauty products which contain herb that order to keep their beauty and youth. Nowadays, organic cosmetics are becoming more accessible to the common people since they are expected to have fewer side effects, as well as an increased level of safety and security. We aim in this study to develop a general-use herbal oil in which a variety of herbs that are readily available to us are utilized and evaluation of the herbal oil formulation was conducted by determining various parameters, such as viscosity, saponification value, pH, etc. [ABSTRACT FROM AUTHOR]

This paper gives an overview of the major research carried out on mathematical modeling for solvent extraction of metals, primarily in the last one decade. The basic theory of solvent extraction as well as, the operational mechanism of various extractors (mixer-settler, column extractors, and liquid membranes) have been described. It discusses different approaches of mathematical modeling for studying solvent extraction of metals, starting from the simple empirical models to more rigorous transport phenomena models. Further, theoretical studies using molecular level modeling techniques such as molecular mechanics (MM), density functional theory, quantum mechanics/MM and Our own N-layered integrated molecular orbital and molecular mechanics (ONIOM) methods implemented for studying metal-ligand complexation have been reviewed. [ABSTRACT FROM AUTHOR]

Edible medicinal plants Curcuma longa, Kaempferia galanga and Zingiber officinale are considered to be suitable for pregnant mother and neonates. Their essential oils are claimed to have therapeutic effects, yet its immunomodulatory activities need to be investigated. To validate the immunomodulatory effect, cord blood monocyte cells (CBMCs) treated with different concentrations of essential oils ranging from 0 to 40 µg/ml. K. galanga oil at 40 µg/ml concentrations upregulated IFN-γ at 49.23 pg/ml, while C. longa oil downregulated the IL-10 at 10.45 pg/ml showing immunostimulant activity on CBMCs. However, Z. officinale oil showed no significant result at any concentration. K. galanga and C. longa oils also showed an increase in lymphocyte proliferation in a dose-dependent manner. The present study was aimed to evaluate the immunomodulatory potentialities of essential oils which will attract the interest of researchers and pharmaceutical industries for clinical studies and other applications in the therapy of diseases related to neonatal infections. [ABSTRACT FROM AUTHOR]

Polyclonal antibodies against Pythium aphanidermatum and Fusarium oxysporum proteins were developed for the detection of rhizome rot in ginger using serological assays. Under optimal experimental conditions, the detection limit of P. aphanidermatum by indirect ELISA was 10 µg/ml with a linear working range from 5 to 100 µg/ml (R2 = 0.994). In case of F. oxysporum, the linear working range was 5-100 µg/ml (R2 = 0.991) and the limit of detection was 25 µg/ml. The developed antibodies showed the highest titer in ELISA at 1:2000 dilutions. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis identified proteins ranging from molecular weights 15-97 kDa and 14-116 kDa of P. aphanidermatum and F. oxysporum isolates, respectively. In Western blot analysis, the developed antisera gave positive reactions against the isolated antigens of the fungi. The antibodies revealed immune-reactive bands of molecular weights 59 and 65 kDa in P. aphanidermatum and 44 and 75 kDa in F. oxysporum. The results suggest that the developed antibodies could be successfully applied for the specific immunodetection of P. aphanidermatum and F. oxysporum at an early stage of rhizome rot disease. [ABSTRACT FROM AUTHOR]