Temperature-Dependent As K-Edge EXAFS Studies of LaFe 1−x Co x AsO (x = 0.0 and 0.11) Single Crystals

Results of magnetization and magnetic susceptibility measurements on undoped and Co-doped FeSi2.5 single crystals are presented. The temperature dependence of the magnetic susceptibility of the Co-doped sample in the range of 5–300 K can be explained by temperature-dependent contributions due to paramagnetic centers and the carriers excited thermally in the extrinsic conductivity region. The values of the paramagnetic Curie temperature and activation energy of the donor levels were estimated. It is also shown that the magnetic susceptibility of Co-doped samples cooled in zero external field and in a field are different. This resembles the properties of spin-glasses and indicates the presence of coupling between magnetic centers.

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The mechanism of work-hardening and slip-band formation

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1957.0163 ◽

1957 ◽

Vol 242 (1229) ◽

pp. 147-159 ◽

Cited By ~ 7

Keyword(s):

Single Crystals ◽

Slip Band ◽

Work Hardening ◽

Stage I ◽

Polycrystalline Materials ◽

Temperature Dependent ◽

Band Formation ◽

Slip Bands ◽

Three Stages ◽

The Difference

A summary is given of some present ideas on the mechanism of work-hardening of single crystals and polycrystalline materials. In particular, the difference is stressed between the three stages of hardening: stage I, or easy glide; stage II, the region of rapid hardening accompanied by short slip lines; and stage III, the region of slow or parabolic hardening which is temperature-dependent and in which long slip bands are formed.

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Temperature-dependent Raman scattering study of tin modified PbZrO3 and PbHfO3 single crystals

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2015.05.093 ◽

2015 ◽

Vol 644 ◽

pp. 854-861 ◽

Cited By ~ 8

Author(s):

I. Jankowska-Sumara ◽

M. Ptak ◽

M. Mączka ◽

A. Majchrowski ◽

T.H. Kim ◽

...

Keyword(s):

Raman Scattering ◽

Single Crystals ◽

Temperature Dependent ◽

Scattering Study

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Temperature-dependent Raman scattering in ferroelectric Bi4−x Nd x Ti3 O12 (x = 0, 0.5, 0.85) single crystals

Journal of Raman Spectroscopy ◽

10.1002/jrs.2376 ◽

2009 ◽

Vol 40 (12) ◽

pp. 2088-2091 ◽

Cited By ~ 37

Author(s):

Kun Liang ◽

Yajun Qi ◽

Chaojing Lu

Keyword(s):

Raman Scattering ◽

Single Crystals ◽

Temperature Dependent

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Temperature dependent photoluminescence studies of ZnSe:I single crystals grown by chemical vapor transport

Pramana ◽

10.1007/bf02847299 ◽

1996 ◽

Vol 47 (2) ◽

pp. 133-143 ◽

Cited By ~ 6

Author(s):

Suruchi Anand ◽

Prabhat Verma ◽

S C Abbi ◽

K P Jain ◽

M J Tafreshi ◽

...

Keyword(s):

Single Crystals ◽

Chemical Vapor ◽

Vapor Transport ◽

Chemical Vapor Transport ◽

Temperature Dependent ◽

Photoluminescence Studies ◽

Temperature Dependent Photoluminescence

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The Temperature-Dependent Ideal Shear Strength of Solid Single Crystals

Journal of Applied Mechanics ◽

10.1115/1.4038884 ◽

2018 ◽

Vol 85 (3) ◽

Cited By ~ 1

Author(s):

Tianbao Cheng ◽

Daining Fang ◽

Yazheng Yang

Keyword(s):

Shear Strength ◽

Theoretical Model ◽

Melting Point ◽

Single Crystals ◽

Elevated Temperatures ◽

Absolute Zero ◽

Temperature Dependent ◽

Temperature Changes ◽

First Time ◽

The Ideal

Knowledge of the ideal shear strength of solid single crystals is of fundamental importance. However, it is very hard to determine this quantity at finite temperatures. In this work, a theoretical model for the temperature-dependent ideal shear strength of solid single crystals is established in the view of energy. To test the drawn model, the ideal shear properties of Al, Cu, and Ni single crystals are calculated and compared with that existing in the literature. The study shows that the ideal shear strength first remains approximately constant and then decreases almost linearly as temperature changes from absolute zero to melting point. As an example of application, the “brittleness parameter” of solids at elevated temperatures is quantitatively characterized for the first time.

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Quaternary intermetallics RE2Pt3Ga4In (RE=Y, Gd-Tm) – intergrowth structures of NdRh2Sn4 and TiNiSi related slabs

Zeitschrift für Kristallographie - Crystalline Materials ◽

10.1515/zkri-2020-0012 ◽

2020 ◽

Vol 235 (4-5) ◽

pp. 117-125

Author(s):

Myroslava Horiacha ◽

Maximilian K. Reimann ◽

Jutta Kösters ◽

Vasyl‘ I. Zaremba ◽

Rainer Pöttgen

Keyword(s):

Single Crystals ◽

High Frequency ◽

Magnetic Moments ◽

Intermetallic Phases ◽

X Ray Diffraction ◽

Temperature Dependent ◽

X Ray ◽

Arc Melting ◽

Intergrowth Structures ◽

A Site

AbstractThe quaternary gallium-rich intermetallic phases RE2Pt3Ga4In with RE = Y and Gd-Tm were synthesized by arc-melting of the elements and subsequent annealing. Small single crystals were obtained by high-frequency annealing of the samples in sealed tantalum ampoules. The polycrystalline samples were characterized through their X-ray powder patterns. The RE2Pt3Ga4In phases crystallize with a site ordering variant of the orthorhombic Y2Rh3Sn5 type, space group Cmc 21. The structures of Gd2Pt3Ga4In, Dy2Pt3Ga4.14In0.86, Er2Pt3Ga4.17In0.83 and Tm2Pt3Ga4.21In0.79 were refined from single-crystal X-ray diffraction data. The single crystals reveal small homogeneity ranges RE2Pt3Ga4±xIn1±x. The striking geometrical structural building units are slightly distorted trigonal prisms around the three crystallographically independent platinum atoms: Pt1@RE4Ga2, Pt2@RE2Ga4 and Pt3@RE2Ga2In2. Based on these prismatic building units, the RE2Pt3Ga4In structures can be described as intergrowth variants of TiNiSi and NdRh2Sn4 related structural slabs. Temperature dependent magnetic susceptibility studies of Gd2Pt3Ga4In and Tb2Pt3Ga4In show Curie-Weiss behavior and the experimental magnetic moments confirm stable trivalent gadolinium respectively terbium. Gd2Pt3Ga4In and Tb2Pt3Ga4In order antiferromagnetically at TN = 15.8(1) and 26.0(1) K. Magnetization curves at 3 K show field-induced spin reorientations.

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