The new quaternary iron arsenide-fluoride SrFeAsF with the tetragonal ZrCuSiAstype structure was synthesized and the crystal structure was determined by X-ray powder diffraction (P4/nmm, a = 399.30(1), c = 895.46(1) pm). SrFeAsF undergoes a structural and magnetic phase transition at 175 K, accompanied by strong anomalies in the specific heat, electrical resistance and magnetic susceptibility. ...

Grindstone Chemistry––a greatly evolved version of Toda"s method of grinding solids together for solvent-free chemical reactions––has been described and its usefulness illustrated by the successful application of this technique to a simplified process for conducting the multi-component Biginelli reaction for the synthesis of physiologically active tetrahydropyrimidinones. ! 2004 Published by El...

“I woke with this marble head in my hands; / It exhausts my elbows and I don’t know where to put it down. / It was falling into the dream as I was coming out of the dream / So our life became one and it will be very diffi cult for it to separate again,” wrote George Seferis about his relationship with art from antiquity (1). Traversing the edges of time has long been the domain of artists and p...

Anaphylaxis is the number one emergency situation in allergy. More than 100 years after its first description, there are still many problems and open questions regarding pathophysiology, diagnosis, treatment, and prevention. Many national and international societies have edited guidelines that give clear recommendations for acute treatment, showing algorithms depending on the severity of the cl...

<sec>The entropy-modulated material has been a hot topic due to its unique design concept and excellent properties. However, previous studies of materials mainly focused on the alloys with simple face-centered cubic, or body-centered hexagonal close-packed structures. In this work, entropy-modulation is introduced into Gd<sub>2</sub>Co<sub>17</sub> based intermetal...

abstract this article tries to look at the jewels of the ancient luristan (nowadays luristan province and some parts of ilam and kermanshah provinces), and to have a survey on this precious art and its typology. these jewels have been gathered by way of many scientific and unscientific excavations at last decades in the ancient sites like: kalmakareh, varkaboud, kalvali, sorkh dom, kamtarlan (k...

one of the important features of achaemenid art is the repetition of almost similar motifs and their consistency during this lengthy era. consequently, a large number of researchers consider the presence of the constant and pre-conceived patterns as necessity for stonecarving, sculptors and metalworkers. apparently, this coordination arising from similar repeated patterns is visible in the acha...

A real-time fluorescent PCR assay using a set of specific primers and a fluorochrome-labelled probe (TaqMan) was developed to quantify the amount of Phytophthora medicaginis DNA in alfalfa plants that were classified as either resistant or susceptible to the pathogen based on visual assessment of disease response. The assay clearly discriminated among three standard check alfalfa populations wi...

The decay of Hf (half life of 9 million years) to W provides a powerful tool to date metal-silicate fractionation in the early solar system. During segregation of metal the siderophile W partitions into the metal phase, whereas the lithophile Hf is preferably incorporated by silicate phases. The formation of iron meteorites during metal-silicate fractionation may have occured during condensatio...

Introduction: The ureilites are an unusual class of carbon-rich, ultramafic, achondritic meteorites, which display both primitive and evolved characteristics. For example, their noble gases (which are carried largely in the diamond phase) display a planetary or fractionated signature, and their O isotopes retain a heterogeneity imparted from the solar nebula [1,2]. Paradoxically, though, the mi...