Fabrication of Yttrium Ferrite Nanoparticles by Solution Combustion Synthesis

The ternary oxide system Y-Fe-O presents fascinating magnetic properties that are sensitive to the crystalline size of particles. There is a major challenge to fabricate these materials in nano-crystalline forms due to particle conglomeration during nucleation and synthesis. In this paper we report the fabrication of nano sized crystalline yttrium ferrite by solution combustion synthesis (SCS) where yttrium and iron nitrates were used as metal precursors with glycine as a fuel. The magnetic properties of the product can be selectively controlled by adjusting the ratio of glycine to metal nitrates. Yttrium ferrite nano-powder was obtained by using three concentration of glycine (3, 6 and 10 wt.%) in the initial exothermic mixture. Increasing glycine content was found to increase the reaction temperature of the system. The structural and magnetic properties of yttrium ferrite before and after annealing at temperature of 1000 °C were investigated by X-ray diffractometry, Differential Scanning Calorimetry (DSC) and cryogenic magnetometry (PPMS, Quantum Design). X-ray diffraction showed that, a broad diffraction peak was found for all samples indicating the amorphous nature of the product. Particle size and product morphology analysis identified that, Nitrate/glycine combustion caused considerable gas evolution, mainly carbon dioxide, N2 and H2O vapor, which caused the synthesized powders to become friable and loosely agglomerated for glycine concentration from 3 wt.% up to 10 wt.%. The study of the magnetic properties of produced materials in a metastable state was performed by measuring dependencies of Magnetization (M) on temperature, and magnetization on magnetic field strength between 5 K and 300 K. Magnetization measurements on temperature zero-fieldcooled and field-cooled show different patterns when the fraction of glycine is increased. The analysis of zero-field-cooled (ZFC), field-cooled (FC) and magnetization curves of annealed samples confirmed that nanoparticles exhibit superparamagnetic behavior. The increasing concentration of glycine leads to an increased blocking temperature

Solution-combustion synthesis and magnetodielectric properties of nanostructured rare earth ferrites

Rare earth ferrites exhibit remarkable magnetodielectric properties that are sensitive to the crystallite size. There is a major challenge to produce these materials in nanoscale due to particles conglomeration during the ferrite nucleation and synthesis. In this paper we report the fabrication of nanostructured particles of rare earth ferrites in the Me-Fe-O system (Me = Y, La, Ce, and Sm) by Solution-Combustion Synthesis (SCS). The yttrium, lanthanum, cerium, samarium and iron nitrates were used as metal precursors and glycine as a fuel. Thermodynamic calculations of Y(NO3)3-2Fe(NO3)3−nC2H5NO2 systems producing Y3Fe5O12 predicted an adiabatic temperature of 2250 K with generating carbon dioxide, nitrogen and water vapor. The considerable gas evolution helps to produce the synthesized powders friable and loosely agglomerated. Adjusting the glycine/metal nitrates ratio can selectively control the crystallite size and magnetodielectric properties of the ferrites. Increasing the glycine content increased the reaction temperature during the SCS and consequently the particle size. Magnetization of zero-field-cooled (ZFC) and field-cooled (FC) ferrites in the temperature range of 1.9–300 K showed different patterns when the fraction of glycine was increased. Analysis of ZFC and FC magnetization curves of annealed samples confirmed that nanoparticles exhibit superparamagnetic behavior. The increasing concentration of glycine leads to escalation of blocking temperature. Reduction of dielectric permittivity (ɛr) toward frequency indicates the relaxation processes in the composites, and the values of ɛr are shifted upward along the operating temperature

Ancient DNA from Mesopotamia suggests distinct Pre-Pottery and Pottery Neolithic migrations into Anatolia

We present the first ancient DNA data from the Pre-Pottery Neolithic of Mesopotamia (Southeastern Turkey and Northern Iraq), Cyprus, and the Northwestern Zagros, along with the first data from Neolithic Armenia. We show that these and neighboring populations were formed through admixture of pre-Neolithic sources related to Anatolian, Caucasus, and Levantine hunter-gatherers, forming a Neolithic continuum of ancestry mirroring the geography of West Asia. By analyzing Pre-Pottery and Pottery Neolithic populations of Anatolia, we show that the former were derived from admixture between Mesopotamian-related and local Epipaleolithic-related sources, but the latter experienced additional Levantine-related gene flow, thus documenting at least two pulses of migration from the Fertile Crescent heartland to the early farmers of Anatolia

The genetic history of the Southern Arc. A bridge between West Asia and Europe

By sequencing 727 ancient individuals from the Southern Arc (Anatolia and its neighbors in Southeastern Europe and West Asia) over 10,000 years, we contextualize its Chalcolithic period and Bronze Age (about 5000 to 1000 BCE), when extensive gene flow entangled it with the Eurasian steppe. Two streams of migration transmitted Caucasus and Anatolian/Levantine ancestry northward, and the Yamnaya pastoralists, formed on the steppe, then spread southward into the Balkans and across the Caucasus into Armenia, where they left numerous patrilineal descendants. Anatolia was transformed by intra-West Asian gene flow, with negligible impact of the later Yamnaya migrations. This contrasts with all other regions where Indo-European languages were spoken, suggesting that the homeland of the IndoAnatolian language family was in West Asia, with only secondary dispersals of non-Anatolian IndoEuropeans from the steppe

A genetic probe into the ancient and medieval history of Southern Europe and West Asia

Literary and archaeological sources have preserved a rich history of Southern Europe and West Asia since the Bronze Age that can be complemented by genetics. Mycenaean period elites in Greece did not differ from the general population and included both people with some steppe ancestry and others, like the Griffin Warrior, without it. Similarly, people in the central area of the Urartian Kingdom around Lake Van lacked the steppe ancestry characteristic of the kingdom's northern provinces. Anatolia exhibited extraordinary continuity down to the Roman and Byzantine periods, with its people serving as the demographic core of much of the Roman Empire, including the city of Rome itself. During medieval times, migrations associated with Slavic and Turkic speakers profoundly affected the region

The genetic history of the Southern Arc: a bridge between West Asia and Europe

By sequencing 727 ancient individuals from the Southern Arc (Anatolia and its neighbors in Southeastern Europe and West Asia) over 10,000 years, we contextualize its Chalcolithic period and Bronze Age (about 5000 to 1000 BCE), when extensive gene flow entangled it with the Eurasian steppe. Two streams of migration transmitted Caucasus and Anatolian/Levantine ancestry northward, and the Yamnaya pastoralists, formed on the steppe, then spread southward into the Balkans and across the Caucasus into Armenia, where they left numerous patrilineal descendants. Anatolia was transformed by intra?West Asian gene flow, with negligible impact of the later Yamnaya migrations. This contrasts with all other regions where Indo-European languages were spoken, suggesting that the homeland of the Indo-Anatolian language family was in West Asia, with only secondary dispersals of non-Anatolian Indo-Europeans from the steppe. Stories about the peopling?and people?of Southern Europe and West Asia have been passed down for thousands of years, and these stories have contributed to our historical understanding of populations. Genomic data provide the opportunity to truly understand these patterns independently from written history. In a trio of papers, Lazaridis et al. examined more than 700 ancient genomes from across this region, the Southern Arc, spanning 11,000 years, from the earliest farming cultures to post-Medieval times (see the Perspective by Arbuckle and Schwandt). On the basis of these results, the authors suggest that earlier reliance on modern phenotypes and ancient writings and artistic depictions provided an inaccurate picture of early Indo-Europeans, and they provide a revised history of the complex migrations and population integrations that shaped these cultures. ?SNV A web of migrations between Anatolia, its neighbors, and the Steppe suggests a West Asian origin of Indo-Anatolian languages

A genetic probe into the ancient and medieval history of Southern Europe and West Asia

Literary and archaeological sources have preserved a rich history of Southern Europe and West Asia since the Bronze Age that can be complemented by genetics. Mycenaean period elites in Greece did not differ from the general population and included both people with some steppe ancestry and others, like the Griffin Warrior, without it. Similarly, people in the central area of the Urartian Kingdom around Lake Van lacked the steppe ancestry characteristic of the kingdom’s northern provinces. Anatolia exhibited extraordinary continuity down to the Roman and Byzantine periods, with its people serving as the demographic core of much of the Roman Empire, including the city of Rome itself. During medieval times, migrations associated with Slavic and Turkic speakers profoundly affected the region

Ancient DNA from Mesopotamia suggests distinct Pre-Pottery and Pottery Neolithic migrations into Anatolia

We present the first ancient DNA data from the Pre-Pottery Neolithic of Mesopotamia (Southeastern Turkey and Northern Iraq), Cyprus, and the Northwestern Zagros, along with the first data from Neolithic Armenia. We show that these and neighboring populations were formed through admixture of pre-Neolithic sources related to Anatolian, Caucasus, and Levantine hunter-gatherers, forming a Neolithic continuum of ancestry mirroring the geography of West Asia. By analyzing Pre-Pottery and Pottery Neolithic populations of Anatolia, we show that the former were derived from admixture between Mesopotamian-related and local Epipaleolithic-related sources, but the latter experienced additional Levantine-related gene flow, thus documenting at least two pulses of migration from the Fertile Crescent heartland to the early farmers of Anatolia