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Competition Between Cubic And Tetragonal Phasesin All-D-Metal Heusler Alloys, X2-Xmn1+Xv (X= Pd, Ni, Pt, Ag, Au, Ir, Co; X= 1, 0): A New Potential Direction Of The Heusler Family, Yilin Han, Mengxin Wu, Yu Feng, Zhenxiang Cheng, Tingting Lin, Tie Yang, Rabah Khenata, Xiaotian Wang
Competition Between Cubic And Tetragonal Phasesin All-D-Metal Heusler Alloys, X2-Xmn1+Xv (X= Pd, Ni, Pt, Ag, Au, Ir, Co; X= 1, 0): A New Potential Direction Of The Heusler Family, Yilin Han, Mengxin Wu, Yu Feng, Zhenxiang Cheng, Tingting Lin, Tie Yang, Rabah Khenata, Xiaotian Wang
Australian Institute for Innovative Materials - Papers
In this work, a series of all-d-metal Heusler alloys, X 2 - x Mn 1 + x V (X = Pd, Ni, Pt, Ag, Au, Ir, Co; x; = 1, 0), were predicted by first principles. The series can be roughly divided into two categories: XMn 2 V (Mn-rich type) and X 2 MnV (Mn-poor type). Using optimized structural analysis, it is shown that the ground state of these all-d-metal Heusler alloys does not fully meet the site-preference rule for classic full-Heusler alloys. All the Mn-rich type alloys tend to form the L2 1 structure, where the two Mn atoms …
Superior Intrinsic Thermoelectric Performance With Zt Of 1.8 In Single-Crystal And Melt-Quenched Highly Dense Cu2-Xse Bulks, Lanling Zhao, Xiaolin Wang, Ji-Yang Wang, Zhenxiang Cheng, S X. Dou, Jun Wang, L Liu
Superior Intrinsic Thermoelectric Performance With Zt Of 1.8 In Single-Crystal And Melt-Quenched Highly Dense Cu2-Xse Bulks, Lanling Zhao, Xiaolin Wang, Ji-Yang Wang, Zhenxiang Cheng, S X. Dou, Jun Wang, L Liu
Australian Institute for Innovative Materials - Papers
Practical applications of the high temperature thermoelectric materials developed so far are partially obstructed by the costly and complicated fabrication process. In this work, we put forward two additional important properties for thermoelectric materials, high crystal symmetry and congruent melting. We propose that the recently discovered thermoelectric material Cu2-xSe, with figure of merit, zT, over 1.5 at T of ~ 1000 K, should meet these requirements, based on our analysis of its crystal structure and the Cu-Se binary phase diagram. We found that its excellent thermoelectric performance is intrinsic, and less dependent on grain size, while highly dense samples can …
Hydrostatic Piezoelectric Properties Of [011] Poled Pb(Mg 1/3nb2/3)O3-Pbtio3 Single Crystals And 2-2 Lamellar Composites, Lili Li, Shujun Zhang, Zhuo Xu, Xuecang Geng, Fei Wen, Jun Luo, Thomas R. Shrout
Hydrostatic Piezoelectric Properties Of [011] Poled Pb(Mg 1/3nb2/3)O3-Pbtio3 Single Crystals And 2-2 Lamellar Composites, Lili Li, Shujun Zhang, Zhuo Xu, Xuecang Geng, Fei Wen, Jun Luo, Thomas R. Shrout
Australian Institute for Innovative Materials - Papers
The hydrostatic piezoelectric properties of [011] poled Pb(Mg 1/3Nb2/3)O3-PbTiO3 (PMN-PT) crystals and corresponding 2-2 crystal/epoxy composites were investigated. The crystal volume ratio and compositional dependencies of the hydrostatic charge and voltage coefficients (dh and gh) and hydrostatic figure of merit (FOM) dh x gh were determined, where large FOM value of 3.2 pm2/N with high stability as a function of hydrostatic pressure was achieved for rhombohedral crystal composites. In addition, the stress amplification effects of the face-plate and different epoxy matrixes were investigated, with maximum FOM value being on the order of 92 pm2/N, indicating that 2-2 crystal/epoxy composites are …
Thermoelectric Performance Of N-Type (Pbte)0.75(Pbs)0.15(Pbse)0.1 Composites, Sima Aminorroaya Yamini, Heng Wang, Dianta Ginting, David R. G Mitchell, S X. Dou, G. Jeffrey Snyder
Thermoelectric Performance Of N-Type (Pbte)0.75(Pbs)0.15(Pbse)0.1 Composites, Sima Aminorroaya Yamini, Heng Wang, Dianta Ginting, David R. G Mitchell, S X. Dou, G. Jeffrey Snyder
Australian Institute for Innovative Materials - Papers
Lead chalcogenides (PbQ, Q = Te, Se, S) have proved to possess high thermoelectric efficiency for both n-type and p-type compounds. Recent success in tuning of electronic band structure, including manipulating the band gap, multiple bands, or introducing resonant states, has led to a significant improvement in the thermoelectric performance of p-type lead chalcogenides compared to the n-type ones. Here, the n-type quaternary composites of (PbTe)0.75(PbS)0.15(PbSe)0.1 are studied to evaluate the effects of nanostructuring on lattice thermal conductivity, carrier mobility, and effective mass variation. The results are compared with the similar ternary systems of (PbTe)1-x(PbSe)x, (PbSe) 1-x(PbS)x, and (PbS)1-x(PbTe)x. The …
Magnetic Properties And Magnetocaloric Effect In Layered Ndmn 1.9v0.1si2, M F. Md Din, Jianli Wang, R Zeng, Shane Kennedy, S J. Campbell, S X. Dou
Magnetic Properties And Magnetocaloric Effect In Layered Ndmn 1.9v0.1si2, M F. Md Din, Jianli Wang, R Zeng, Shane Kennedy, S J. Campbell, S X. Dou
Australian Institute for Innovative Materials - Papers
The structural and magnetic properties of the compounds NdMn2-xVxSi2 have been studied by x-ray and high resolution neutron powder diffraction, specific heat, dc magnetization, and differential scanning calorimetry measurements over the temperature range 3-450 K. The Curie temperature and Néel temperature of layered NdMn1.9V0.1Si2 are been indicate at TC ~ 24 K and TN ~ 376 K respectively. The giant magnetocaloric effect (GMCE) around TC is found in layered NdMn1.9V0.1Si2 associated with first order magnetic transition from antiferromagnetic [AFil-type] to ferromagnetic [F(Nd)+Fmc]. This behaviorhas been confirmed as contribution of the magnetostructural coupling by using neutron powder diffraction. The magnetic entropy …
Magnetic Transitions And The Magnetocaloric Effect In The Pr 1-Xyxmn2ge2 System, Jianli Wang, S J. Campbell, M F. Md Din, S J. Kennedy, M Hofmann
Magnetic Transitions And The Magnetocaloric Effect In The Pr 1-Xyxmn2ge2 System, Jianli Wang, S J. Campbell, M F. Md Din, S J. Kennedy, M Hofmann
Australian Institute for Innovative Materials - Papers
Layered rare earth compounds in the RMn2X2 series (R = rare-earth; X = Ge, Si) are of interest for potential cooling applications at lower temperatures as they enable the structural and magnetic behavior to be controlled via substitution of R, Mn, and X atoms on the 2a, 4d, and 4e sites respectively. We continue investigations of the Pr1−xYxMn2Ge2 magnetic phase diagram as functions of both composition and Mn-Mn spacing using X-ray and neutron diffraction, magnetization and differential scanning calorimetry measurements. Pr1−xYxMn2Ge2 exhibits an extended region of re-entrant ferromagnetism around x ∼ 0.5 with re-entrant ferromagnetism at inline image for Pr0.5Y0.5Mn2Ge2. …
2-(10′,10′-Dimethyl-3′-Sulfanylidene-4′- Azatricyclo[5.2.1.01,5]Decan-2′-Yl)-10,10-Dimethyl-4- Azatricyclo[5.2.1.01,5]Decane-3-Thione, Ashley Walker, Craig M. Forsyth, Patrick Perlmutter
2-(10′,10′-Dimethyl-3′-Sulfanylidene-4′- Azatricyclo[5.2.1.01,5]Decan-2′-Yl)-10,10-Dimethyl-4- Azatricyclo[5.2.1.01,5]Decane-3-Thione, Ashley Walker, Craig M. Forsyth, Patrick Perlmutter
Australian Institute for Innovative Materials - Papers
The title compound, C28H40N2O2S2, was obtained as a minor product from an anti-aldol reaction between the corresponding N-propionylthiolactam and benzaldehyde. The asymmetric unit contains one half-molecule, which is completed by inversion symmetry. The molecule displays a nearly eclipsed conformation along the central C-C bond with a C-C-C-C- torsion angle of 20.4 (3)°.
1-3 Piezoelectric Composites For High-Temperature Transducer Applications, Lili Li, Shujun Zhang, Zhuo Xu, Fei Wen, Xuecang Geng, Hyeong Jae Lee, Thomas R. Shrout
1-3 Piezoelectric Composites For High-Temperature Transducer Applications, Lili Li, Shujun Zhang, Zhuo Xu, Fei Wen, Xuecang Geng, Hyeong Jae Lee, Thomas R. Shrout
Australian Institute for Innovative Materials - Papers
High-temperature Pb(Zr,Ti)O3/epoxy 1-3 composites were fabricated using the dice and fill method. The epoxy filler was modified with glass spheres in order to improve the thermal reliability of the composites at elevated temperatures. Temperature-dependent dielectric and electromechanical properties of the composites were measured after ageing at 250 °C with different dwelling times. Obvious cracks were observed and the electrodes were damaged in the composite with unmodified epoxy after 200 h, leading to the failure of the composite. In contrast, composites with >12 vol% glass sphere loaded epoxies were found to exhibit minimal electrical property variation after ageing for 500 h, …
Raman Scattering Studies Of Strain Effects In (100) And (311)B Gaas 1-Xbix Epitaxial Layers, J A. Steele, Roger A. Lewis, M Henini, O M. Lemine, A Alkaoud
Raman Scattering Studies Of Strain Effects In (100) And (311)B Gaas 1-Xbix Epitaxial Layers, J A. Steele, Roger A. Lewis, M Henini, O M. Lemine, A Alkaoud
Australian Institute for Innovative Materials - Papers
We report room-temperature Raman studies of strained (100) and (311)B GaAs1-xBix epitaxial layers for x ≤ 0.039. The Raman spectra exhibit a two-mode behavior, as well as disorder-activated GaAs-like phonons. The experimental results show that the GaAs-like LO(Γ) mode experiences a strong composition-dependent redshift as a result of alloying. The peak frequency decreases linearly from the value for pure GaAs (∼293 cm-1) with the alloyed Bi fraction x and the introduced in-plane lattice strain ε, by Δ ω LO = Δ ω alloy-Δ ω strain. X-ray diffraction measurements are used to determine x and ε allowing Δ ω alloy to …
Isomorphism In Two (E)-1-(4-Halophenyl)-N-[1-(4-Methylphenyl)-1h-Imidazol-4-Yl]Methanimines (Halide = Cl, Br), Hanna Skrzypiec, Radoslaw Mazurek, Pawel Wagner, Maciej Kubicki
Isomorphism In Two (E)-1-(4-Halophenyl)-N-[1-(4-Methylphenyl)-1h-Imidazol-4-Yl]Methanimines (Halide = Cl, Br), Hanna Skrzypiec, Radoslaw Mazurek, Pawel Wagner, Maciej Kubicki
Australian Institute for Innovative Materials - Papers
The crystal structures of two imidazole-4-imines, (E)-1-(4-chlorophenyl)-N-[1-(4-methylphenyl)-1H-imidazol-4-yl]methanimine (1, C17H14ClN3), and (E)-1-(4-bromophenyl)-N-[1-(4-methylphenyl)-1H-imidazol-4-yl]methanimine, (2, C17H14BrN3), are isomorphous, the isostructurality index is 99.4 %. Both compounds crystallize in the triclinic space group P-1 with unit cell parameters at 100(1) K as follows: for (1), a = 7.9767(5) Å, b = 10.9517(7) Å, c = 16.6753(12) Å, α = 80.522(6)°, β = 87.046(6)°, γ = 89.207(5)°, and for (2), a = 8.0720(7) Å, b = 10.9334(10) Å, c = 16.8433(13) Å, α = 81.161(7)°, β = 86.605(7)°, γ = 89.505(7)°. The structures contain two symmetry—independent but conformationally similar molecules in the asymmetric unit (Z’ …
5-Methoxy-2-Methyl-4-Nitro-1-Phenyl-1h-Imidazole, Pawel Wagner, Maciej Kubicki
5-Methoxy-2-Methyl-4-Nitro-1-Phenyl-1h-Imidazole, Pawel Wagner, Maciej Kubicki
Australian Institute for Innovative Materials - Papers
The title compound, C11H11N3O3, contains two planar fragments, viz. the imidazole and phenyl rings. These rings are significantly twisted with respect one to another, with a dihedral angle of 63.99 (8)°. The nitro group is almost coplanar with the imidazole plane, while the methoxy group is almost perpendicular to it [the C—C—O—C torsion angle is 65.1 (4)°]. In spite of this, there is a short C(methoxy)—H...O(nitro) contact that might be regarded as an intramolecular hydrogen bond. Weak intermolecular C—H...N(imidazole) and C—H...O(nitro) hydrogen bonds create quite a complicated network that consists of …
2-Methyl-4-Nitro-1-(3-Pyridyl)-1h-Imidazole, Maciej Kubicki, Pawel Wagner
2-Methyl-4-Nitro-1-(3-Pyridyl)-1h-Imidazole, Maciej Kubicki, Pawel Wagner
Australian Institute for Innovative Materials - Papers
The imidazole and pyridine rings in the title compound, C9H8N4O4, are twisted with respect to one another, with a dihedral angle of 48.30 (4)°. The nitro group is almost coplanar with the imidazole plane. The crystal packing involves some weak C—H...N and C—H...O hydrogen bonds, of which the strongest, between the imidazole CH group and a nitro O atom [H...O 2.396 (15) Å], forms a centrosymmetric dimer.
Ring Transformations In The Reactions Of 1,4-Dinitropyrazole With N-Nucleophiles, Rafal Jedrysiak, Marcin Sawicki, Pawel Wagner, Jerzy Suwinski
Ring Transformations In The Reactions Of 1,4-Dinitropyrazole With N-Nucleophiles, Rafal Jedrysiak, Marcin Sawicki, Pawel Wagner, Jerzy Suwinski
Australian Institute for Innovative Materials - Papers
The reactions of 1,4-dinitropyrazole with primary amines, hydrazines, hydroxylamine and amidines were studied. 1,4-Dinitropyrazole in these reactions served as the synthetic equiv. of nitromalonaldehyde. The reaction of dinitropyrazole with primary arylhydrazines proved to be a convenient approach to the synthesis of 1-aryl-4-nitropyrazoles.
2-Methyl-4-Nitro-1-(4-Nitrophenyl)-1h-Imidazole, Pawel Wagner, Maciej Kubicki
2-Methyl-4-Nitro-1-(4-Nitrophenyl)-1h-Imidazole, Pawel Wagner, Maciej Kubicki
Australian Institute for Innovative Materials - Papers
In the title compound, C10H8N4O4, two planar fragments, viz. the imidazole and nitrophenyl rings, are tilted at a dihedral of 57.89 (7)°. The nitro groups are twisted with respect to the neighbouring ring planes; the dihedral angle is 7.0 (3)° for imidazole and 9.68 (8)° for benzene. The crystal structure consists of centrosymmetric dimers generated by C—H...O hydrogen bonds, which are connected by C—H...N hydrogen bonds into rows along the [001] direction. The neighbouring rows are connected via C—H...O interactions into a two-dimensional network in the bc plane.
2-Methoxy-1-Methyl-4-Nitro-1h-Imidazole, Maciej Kubicki, Pawel Wagner
2-Methoxy-1-Methyl-4-Nitro-1h-Imidazole, Maciej Kubicki, Pawel Wagner
Australian Institute for Innovative Materials - Papers
The molecule of the title compound, C5H7N3O3, is approximately planar. The maximum deviation from the least-squares plane calculated for all non-H atoms is 0.054 (2) Å. The dihedral angles between the mean plane of the imidazole ring [planar within 0.0017 (6) Å] and the planes of the nitro and methoxy groups are 2.9 (1) and 1.2 (1)°, respectively. The molecules are held together by weak C—H...N and C—H...O interactions and by van der Waals forces.
1,8,14,20-Tetraoxa-11,23-Dithiatricyclo[21.3.0.09,13]Hexacosa-9,12,21,24-Tetraene, Pawel Wagner, Maciej Kubicki, Mieczyslaw Lapkowski
1,8,14,20-Tetraoxa-11,23-Dithiatricyclo[21.3.0.09,13]Hexacosa-9,12,21,24-Tetraene, Pawel Wagner, Maciej Kubicki, Mieczyslaw Lapkowski
Australian Institute for Innovative Materials - Papers
Crystals of the title compd. are orthorhombic, space group Pbca; Z = 4. Mols. lie on crystallog. centers of inversion, but have approx. C2h mol. symmetry. The parallel thiophene rings are almost exactly planar; the overall conformation of the mol. is chair-like. The mols. have voids that could, in principle, accommodate small guest mols., although in the crystal structure access to these voids is blocked by neighboring mols.
Electrochemical Study Of 1,3-Indandione Derivatives Of Terthiophenes, Mieczyslaw Lapkowski, Sylwia Plewa, Pawel Wagner, David L. Officer
Electrochemical Study Of 1,3-Indandione Derivatives Of Terthiophenes, Mieczyslaw Lapkowski, Sylwia Plewa, Pawel Wagner, David L. Officer
Australian Institute for Innovative Materials - Papers
Properties and behavior of a group of four newly synthesized derivatives of terthiophene and terthienylenvinylene was studied. All four investigated monomers bear a 1,3-indandione substituent at the central thiophene ring and two of them (ThIV, ThIVM) have additional vinyl bonds introduced between the thiophene rings. In addition, ThIM and ThIVM have 5 positions of the two terminal rings blocked with methyl groups. The measurements were done using cyclic voltamperometry (CV) in solutions of 0.1M Bu4NBF4 in CH2Cl2. It was found that ThI and ThIV polymerise easily. CV of ThI reveals a reduction peak …
Spin Singlet Pairing In The Superconducting State Of Naxco02 1.3h2o: Evidence From A 59co Knight Shift In A Single Crystal, Guo-Qing Zheng, Kazuaki Matano, Dapeng Chen, C T. Lin
Spin Singlet Pairing In The Superconducting State Of Naxco02 1.3h2o: Evidence From A 59co Knight Shift In A Single Crystal, Guo-Qing Zheng, Kazuaki Matano, Dapeng Chen, C T. Lin
Australian Institute for Innovative Materials - Papers
We report a 59Co Knight-shift measurement in a single crystal of the cobalt oxide superconductor NaxCoO2∙1.3H2O (Tc=4.25 K). We find that the shift due to the spin susceptibility, Ks, is substantially large and anisotropic, with the spin shift along the a-axis Kas being two times that along the c-axis Kcs. The shift decreases with decreasing temperature (T) down to T≈100 K, then becomes a constant until superconductivity sets in. Both Kas and Kcs decrease below Tc. Our results indicate unambiguously that the electron pairing in the superconducting state is in the spin singlet form.
1-(4-Chlorophenyl)-2-Methyl-4-Nitro-5-(1-Piperidyl)-1h-Imidazole, Maciej Kubicki, Pawel Wagner
1-(4-Chlorophenyl)-2-Methyl-4-Nitro-5-(1-Piperidyl)-1h-Imidazole, Maciej Kubicki, Pawel Wagner
Australian Institute for Innovative Materials - Papers
The only specific interactions that influence the crystal packing of the title compound, C15H17ClN4O2, are weak C-H...N and C-H...Cl hydrogen bonds, even though there is a possibility of, for example, pi-pi stacking or halogen bonding. The dihedral angle between the mean planes of the imidazole and benzene rings is 59.82 (5) degrees . The length of the C-N bond connecting the imidazole and piperidine fragments is correlated with the degree of pyramidalization of the piperidine N atom.
1,4-Bis[(1-Methyl-1-Phenylethyl)Peroxymethyl]Benzene, Nikodem Kuznik, Jan Zawadiak, Angelika Wieckol, Danuta Gilner, Pawel Wagner, Maciej Kubicki
1,4-Bis[(1-Methyl-1-Phenylethyl)Peroxymethyl]Benzene, Nikodem Kuznik, Jan Zawadiak, Angelika Wieckol, Danuta Gilner, Pawel Wagner, Maciej Kubicki
Australian Institute for Innovative Materials - Papers
The title compound, C26H30O4, is one of the first alkyl bis-peroxides to be structurally characterized. The molecule lies on a centre of inversion and therefore the terminal phenyl rings are parallel. Although there are three aromatic rings in the molecule, the C—O—O—C torsion angle of 163.10 (10)° is close to the value found in Me3COOCMe3.
Two 1-Substituted 4-Nitroimidazoles, Maciej Kubicki, Teresa Borowiak, Jerzy Suwinski, Pawel Wagner
Two 1-Substituted 4-Nitroimidazoles, Maciej Kubicki, Teresa Borowiak, Jerzy Suwinski, Pawel Wagner
Australian Institute for Innovative Materials - Papers
Crystalline 4-nitro-1-phenylimidazole, C9H7N3O2, (I), and 4′-nitro-1-phenyl-4,1′-biiimidazole, C12H9N5O2, (II), contain C—H⃛O and C—H⃛N hydrogen bonds, connecting the molecules into infinite chains. The aromatic fragments in both compounds are nearly planar. The dihedral angles between the benzene and imidazole rings are 26.78 (5)° in (I) and 29.36 (8)° in (II).