Zener Disaccommodation In Dilute F.C.C. Co-Ti Alloys

The magnetic Dis accommodation, i.e., the time dependence of the low field magnetic permeability, was investigated in cobalt base alloys containing 0-5.1 at.% (0-4.2 wt.%) titanium in the temperature range 400-700°C. A strong temperature dependence of the Dis accommodation observed in the range 430-530°C could be accounted for predominantly by a single first order relaxation process. Analyzing the data in terms of (a) a single exponential relaxation, (b) a lognormal distribution of relaxation times, and (c) a sum of exponential relaxations, it was shown that the relaxation strength varies as the square of the titanium concentration and that the relaxation is characterized by an activation enthalpy of 69 ± 1 kcal/mole and a τ0 of the order of 10-16 sec. The Dis accommodation was attributed to the reorientation of substitutional solute atom (titanium) pairs. From the temperature dependence of the relaxation strength the binding energy of Ti atom pairs was determined to be 0.17 ± 0.08 eV. © 1968

Interstitial Solute Trapping In Irradiated And Quenched Iron

The interaction of interstitial carbon and nitrogen solutes with defects produced by low temperature neutron irradiation and by quenching was studied in high purity and Ferrovac E iron. Magnetic Dis accommodation techniques were applied to determine the interstitial solute content after irradiation and upon annealing. Doses of about 1017 neutrons/cm2 caused the trapping of about 20 ppm (atomic) interstitial solutes at 65 (carbon) and 40°C (nitrogen). Trapping of carbon in a Ferrovac E iron alloy occurred during a fast quench from 880°C. After trapping, the interstitial solutes reappeared in solid solution at 300 (carbon, neutron irradiation), 200 (nitrogen, neutron irradiation), and 620°C (carbon, quenching). Various possibilities for the defect traps were considered and it was concluded that trapping of the interstitial solutes occurred at iron interstitial clusters after neutron irradiation and at vacancy type defects after quenching. Copyright © 1968 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinhei

Ветро-дизельная система электроснабжения поселка

Работа направлена на решение проблемы электроснабжения отдаленных районов. Объектом исследования является гибридная ветро-дизельная система электроснабжения, находящаяся на юге Кемеровской области на высоте 1260 метров. В процессе исследования проводились анализ материалов в открытом доступе, запросы производителям, технико-экономическое сравнение. В результате исследования определен наиболее выгодный вариант. Область применения: энергодефицитные отдаленные районы, наиболее перспективные с точки зрения малой энергетики и обладающие потенциалом ВИЭ, в частности ветропотенциалом. Экономическая эффективность проекта заключается в снижении стоимости электроэнергии в шесть раз.Die Arbeit zielt auf die Losung der Energieversorgung von entlegenen Gebieten. Gegenstand der Studie ist ein Hybrid wind-Diesel-System der Elektrizitatsversorgung, das sich im Suden vom Gebiet Kemerowo auf einer Hohe von 1260 Meter. In der Studie wurden fur die Analyse von Materialien in der offentlichkeit, Anfragen von Herstellern, die technisch-wirtschaftlichen Vergleich. Die Studie ermittelt die Gunstigste Variante. Einsatzbereich: energiedefizite Randgebiete, die vielversprechendsten in Bezug auf niedrige Energie und mit dem Potential der erneuerbaren Energien, insbesondere Energiepotenzial. Die Wirtschaftseffektivitat des Projektes besteht in der Reduzierung der Kosten der Stromerzeugung in sechs mal

Growth and electronic and magnetic structure of iron oxide films on Pt(111)

Ultrathin (111)-oriented polar iron oxide films were grown on a Pt(111) single crystal either by the reactive deposition of iron or oxidation of metallic iron monolayers. These films were characterized using low energy electron diffraction, scanning tunneling microscopy and conversion electron Mossbauer spectroscopy. The reactive deposition of Fe led to the island growth of Fe3O4, in which the electronic and magnetic properties of the bulk material were modulated by superparamagnetic size effects for thicknesses below 2 nm, revealing specific surface and interface features. In contrast, the oxide films with FeO stoichiometry, which could be stabilized as thick as 4 nm under special preparation conditions, had electronic and magnetic properties that were very different from their bulk counterpart, w\"ustite. Unusual long range magnetic order appeared at room temperature for thicknesses between three and ten monolayers, the appearance of which requires severe structural modification from the rock-salt structure.Comment: 17 pages, 6 figures, 50 reference

Adaptive modulations of martensites

Modulated phases occur in numerous functional materials like giant ferroelectrics and magnetic shape memory alloys. To understand the origin of these phases, we review and generalize the concept of adaptive martensite. As a starting point, we investigate the coexistence of austenite, adaptive 14M phase and tetragonal martensite in Ni-Mn-Ga magnetic shape memory alloy epitaxial films. The modulated martensite can be constructed from nanotwinned variants of a tetragonal martensite phase. By combining the concept of adaptive martensite with branching of twin variants, we can explain key features of modulated phases from a microscopic view. This includes phase stability, the sequence of 6M-10M-NM intermartensitic transitions, and magnetocrystalline anisotropy.Comment: 4 pages manuscript, 8 pages supplemen

21. Yüzyıl İçin İstenen/Gerekli Kütüphaneci Becerileri ve Kariyer Planlaması

21. yüzyılın değişen koşullarında kütüphane bir kütüphanecinin eleştirel düşünme ve çözüm bulma, iletişim, takım çalışması ve işbirliği ve yaratıcılık ve yenilikçi olma gibi özelliklere sahip olması gerektiği dikkat çekmektedir. Kütüphanecinin bu yeni koşullara uyum sağlaması son derece büyük bir önem taşımaktadır

The Static and Dynamic Lattice Changes Induced by Hydrogen Adsorption on NiAl(110)

Static and dynamic changes induced by adsorption of atomic hydrogen on the NiAl(110) lattice at 130 K have been examined as a function of adsorbate coverage. Adsorbed hydrogen exists in three distinct phases. At low coverages the hydrogen is itinerant because of quantum tunneling between sites and exhibits no observable vibrational modes. Between 0.4 ML and 0.6 ML, substrate mediated interactions produce an ordered superstructure with c(2x2) symmetry, and at higher coverages, hydrogen exists as a disordered lattice gas. This picture of how hydrogen interacts with NiAl(110) is developed from our data and compared to current theoretical predictions.Comment: 36 pages, including 12 figures, 2 tables and 58 reference