Investigations of Y<inf>2</inf>SiO<inf>5</inf>: Nd¹⁴³ by ESR method

© 2016 Elsevier B.V.Here we present the investigation of Y2SiO5 monocrystals doped by isotopically pure 143Nd3+(0.025%) impurity by X-ray and electron spin resonance methods. The crystal structure parameters of Y2SiO5 monocrystal and microscopic parameters: g-tensors and hyperfine structure parameters of two nonequivalent Nd3+ paramagnetic centers were determined

Investigations of Y<inf>2</inf>SiO<inf>5</inf>: Nd¹⁴³ by ESR method

© 2016 Elsevier B.V.Here we present the investigation of Y2SiO5 monocrystals doped by isotopically pure 143Nd3+(0.025%) impurity by X-ray and electron spin resonance methods. The crystal structure parameters of Y2SiO5 monocrystal and microscopic parameters: g-tensors and hyperfine structure parameters of two nonequivalent Nd3+ paramagnetic centers were determined

ESR Study of Y<inf>2</inf>SiO<inf>5</inf>:Nd¹⁴³ Isotopically Pure Impurity Crystals for Quantum Memory

© 2017, Springer-Verlag Wien.Two Y2SiO5 single crystals doped with 0.001 at.% of the 143Nd3+ ion (sample I containing the only 28Si isotope) and (sample II with the natural abundance of silicon isotopes) were studied using magnetic resonance methods. The spin–spin and spin–lattice relaxation times were measured at 9.7 GHz between 4 and 10 K. It is established that three relaxation processes describe temperature dependences of the spin–lattice relaxation for both crystals. They are one-phonon, two-phonon Raman and two-phonon Orbach–Aminov relaxation processes. It is established that temperature dependence of spin–spin relaxation time differs for different hyperfine components of the electron paramagnetic resonance spectrum of neodymium ions and depends on the kind of the neodymium isotope (143Nd or 145Nd)

Magnetoelectric ordering of BiFeO3 from the perspective of crystal chemistry

In this paper we examine the role of crystal chemistry factors in creating conditions for formation of magnetoelectric ordering in BiFeO3. It is generally accepted that the main reason of the ferroelectric distortion in BiFeO3 is concerned with a stereochemical activity of the Bi lone pair. However, the lone pair is stereochemically active in the paraelectric orthorhombic beta-phase as well. We demonstrate that a crucial role in emerging of phase transitions of the metal-insulator, paraelectric-ferroelectric and magnetic disorder-order types belongs to the change of the degree of the lone pair stereochemical activity - its consecutive increase with the temperature decrease. Using the structural data, we calculated the sign and strength of magnetic couplings in BiFeO3 in the range from 945 C down to 25 C and found the couplings, which undergo the antiferromagnetic-ferromagnetic transition with the temperature decrease and give rise to the antiferromagnetic ordering and its delay in regard to temperature, as compared to the ferroelectric ordering. We discuss the reasons of emerging of the spatially modulated spin structure and its suppression by doping with La3+.Comment: 18 pages, 5 figures, 3 table

Crystal environment of impurity Nd³⁺ion in yttrium and scandium orthosilicate crystals

© 2018 The ESEEM spectroscopy was used to determine positions of the 143Nd3+impurity ions in Y2SiO5single crystal. It is established that neodymium ions substitute yttrium ions in the Y2 positions with seven nearest oxygen ions. Crystal field parameters of 143Nd3+impurity centers in isotopically pure Y228SiO5and Sc228SiO5single crystals were determined using data of CW EPR spectroscopy and the known energy level schemes

Investigations of Y<inf>2</inf>SiO<inf>5</inf>: Nd¹⁴³ by ESR method

© 2016 Elsevier B.V.Here we present the investigation of Y2SiO5 monocrystals doped by isotopically pure 143Nd3+(0.025%) impurity by X-ray and electron spin resonance methods. The crystal structure parameters of Y2SiO5 monocrystal and microscopic parameters: g-tensors and hyperfine structure parameters of two nonequivalent Nd3+ paramagnetic centers were determined

Crystal environment of impurity Nd³⁺ion in yttrium and scandium orthosilicate crystals

© 2018 The ESEEM spectroscopy was used to determine positions of the 143Nd3+impurity ions in Y2SiO5single crystal. It is established that neodymium ions substitute yttrium ions in the Y2 positions with seven nearest oxygen ions. Crystal field parameters of 143Nd3+impurity centers in isotopically pure Y228SiO5and Sc228SiO5single crystals were determined using data of CW EPR spectroscopy and the known energy level schemes

ESR Study of Y<inf>2</inf>SiO<inf>5</inf>:Nd¹⁴³ Isotopically Pure Impurity Crystals for Quantum Memory

© 2017, Springer-Verlag Wien.Two Y2SiO5 single crystals doped with 0.001 at.% of the 143Nd3+ ion (sample I containing the only 28Si isotope) and (sample II with the natural abundance of silicon isotopes) were studied using magnetic resonance methods. The spin–spin and spin–lattice relaxation times were measured at 9.7 GHz between 4 and 10 K. It is established that three relaxation processes describe temperature dependences of the spin–lattice relaxation for both crystals. They are one-phonon, two-phonon Raman and two-phonon Orbach–Aminov relaxation processes. It is established that temperature dependence of spin–spin relaxation time differs for different hyperfine components of the electron paramagnetic resonance spectrum of neodymium ions and depends on the kind of the neodymium isotope (143Nd or 145Nd)

PERENCANAAN JALAN DENGAN PERKERASAN KAKU (RIGID PAVEMENT) DI RUAS JALAN BRIGJEN KATAMSO PERBATASAN METRO-LAMPUNG TENGAH (WATES)

Perkerasan jalan raya adalah merupakan suatu konstruksi yang disusun menjadi satu kesatuan yang kuat yang membentuk perkerasan jalan sebagai sarana maupun prasarana yang menjadi lintasan yang bermanfaat untuk melewatkan lalu lintas (traffic) dari suatu tempat ke tempat lain. Perkerasan jalan ada tiga jenis yaitu Perkerasan Lentur, Perkerasan Kaku dan Pekerasan komposit yaitu kombinasi dari perkerasan lentur dengan perkerasan kaku. Konstruksi perkerasan jalan kaku (Rigid Pavement), yaitu suatu susunan konstruksi perkerasan yang lapisan atasnya menggunakan pelat beton yang terletak diatas lapisan pondasi atau langsung diatas tanah dasar (subgrade). Perencanaan berada di ruas jalan Sukarno-Hata Kelurahan Ganjar Agung Kota Metro. Perencanaan ini meliputi Survei lalu lintas dan mengetahui California Bearing Ratio (CBR) tanah dasar. Tujuan dari perencanaan ini adalah mempelajari dan memahami dalam merencanakan perkerasan kaku (rigid pavement) dengan mengacu pada metode dan peraturan yang ada. Dari hasil perencanaan didapat, Ketebalan struktur perkerasan kaku digunakan 22 cm dengan beton K-350 dengan CBR desain 5,70 %. Tulangan yang digunakan masing – masing sebagai berikut : Tulangan memanjang  16 mm jarak 100 mm, Tulangan melintang  12 mm jarak 250 mm, Dowel (ruji), diameter 1 ¼” (32 mm), panjang 450 mm, jarak 300 mm, Batang Pengikat (tie bar), jarak tie bar   16 – 300, jarak dudukan  12–500 mm.