4,716 research outputs found
Yb9+xCuMg4x (x = 0.034): A Phase Formed by Lanthanoids
No full textAtom order in the crystal structures of Yb2Cu2-xMg (x = 0.17; Mo2FeB2-type; P4/mbm; a = 0.75592(2) nm; c = 0.40282(1) nm) and Yb9 + xCuMg4 - x (x = 0.034; Hf9Mo4B-type; P63/mmc; a = 1.0169(5) nm; c = 1.0290(5) nm) was determined from powder and X-ray single-crystal counter data analyses supported by electron probe microanalyses. Among the group of the so-called κ -phases, Yb9 + xCuMg4 - x is the first representative formed by a lanthanoid element. The structure of this κ -phase can be viewed as a typical network of corner-connected empty Yb6-octahedra, which encompass Yb6Mg6-icosahedra (filled by a mix of Mg/Yb atoms) and Yb6-trigonal prisms centered by Cu atoms to complete the three-dimensional metal framework. From another point of view, the same structure is considered as built from in finite polyicosahedral columns of Yb9Mg4 composition with Cu atoms located in trigonal prismatic interstices, highlighting similarities with other Yb-rich Yb−Cu−Mg phases. Density functional theory (DFT) calculations classify Yb9CuMg4 as a polar intermetallic. Metallic-like behavior is inferred from the Sommerfeld constant, γ = 49.2 mJ/molK2, derived from the electronic density of states, calculated at the Fermi level. DFT integration of the f-density of states indicates almost completely filled f-states, revealing 13.6 and 13.7 electrons in the valence band for Yb1 and Yb2 atoms, respectively, close to the Yb2+ ground state (1S0) for both Yb atoms. Magnetic susceptibility data recorded on the same compound are consistent with a nonmagnetic divalent Yb2+ state. Temperature-dependent heat capacity data display a metallic behavior characterized by a small Sommerfeld constant γ = 64.8 mJ/molK2 and a rather low Debye temperature ΘD = 140 K as typical for soft materials
La2Pd3Ge5 and Nd2Pd3Ge5 Compounds: Chemical Bonding and Physical Properties
No full textThe two La2Pd3Ge5 and Nd2Pd3Ge5 compounds, crystallizing in the oI40-U2Co3Ge5 crystal structure, were targeted for analysis of their chemical bonding and physical properties. The compounds of interest were obtained by arc melting and characterized by differential thermal analysis, scanning electron microscopy, and X-ray diffraction both on powder and on a single crystal (for the La analogue), to ensure the high quality of the samples and accurate crystallographic data. Chemical bonding was studied by analyzing the electronic structure and effective QTAIM charges of La2Pd3Ge5. A significant charge transfer mainly occurs from La to Pd so that Ge species assume tiny negative charges. This result, together with the -(I)COHP analysis, suggests that, in addition to the expected homopolar Ge bonds within zigzag chains, heteropolar interactions between Ge and the surrounding La and Pd occur with multicenter character. Covalent La-Pd interactions increase the complexity of chemical bonding, which could not be adequately described by the simplified, formally obeyed, Zintl-Klemm scheme. Electric resistivity, specific heat, magnetization, and magnetic susceptibility as a function of temperature indicate for both compounds a metallic-like behavior. For Nd2Pd3Ge5, two low-temperature phase transitions are detected, leading to an antiferromagnetic ground state
Joseph Bimeler book order to Peter Kaufmann, February 14, 1845
No full textOrder of two dozen German A.B.C. books (primers) by J.M. Bimeler (by Lewis F. Birk) from Peter Kaufmann.
Led by Joseph Bimeler (sometimes spelled Bäumeler) in 1817, a group of Lutheran separatists left Germany and eventually established the small community of Zoar in Tuscarawas County, Ohio. The group formed the Society of Separatists of Zoar, in which each person donated his or her property to the community as a whole, and in exchange for their work, the society would provide for them. After decades of economic prosperity, the unity of the village declined, and by 1898 the Zoarites disbanded the society.
Peter Kaufmann was a German immigrant and intellectual. He arrived first in Philadelphia, Pennsylvania, in 1820; in 1826 he became professor of languages at the Harmony Society town of Economy, Pennsylvania. In 1827, Kaufmann led the establishment of Teutonia, a utopian community in Columbiana County, Ohio, and published its weekly titled "Teutonia: The Herald of a Better Time." Following this he moved to Canton, Ohio, where he became translator and editor of "Der Vaterlandsfreund und Geist der Zeit" under Solomon Sala. Additionally, Kaufmann wrote a number of books on education, as well as a German almanac. He was also an influential Democrat, counting President Van Buren among his friends, and knew Ralph Waldo Emerson
Composting of aged reed bed biosolids for beneficial reuse: a case study in New Jersey, USA
No full textReed beds with Phragmites australis (common reed) have been utilized to decrease the water, nutrient and volatile solids content of sewage sludge. An efficient disposal/reuse option was sought for reed bed biosolids accumulated over a 15 year period at a wastewater treatment facility in New Jersey, USA. The study facility had 14 reed beds, each with 1000 wet tons capacity, which were full, and so the solids needed to be removed. Because P. australis is considered an invasive species in New Jersey and several other states in the United States, disposal or reuse of solids containing this plant is regulated. Composting was examined as a potential treatment for destroying the plant’s reproductive rhizomes. The high temperatures achieved during composting were also tested to determine if regulatory criteria for pathogen reduction could be met, making the composted product suitable for unrestricted land application. Preliminary studies indicated the sludge had stabilized to the point where self-heating did not occur. Among the carbon amendments tested in the laboratory to stimulate compositing activity, Phragmites above ground biomass was determined to be most suitable. In a field test, Phragmites above ground biomass was mixed with reed bed biosolids at a 1:2 (w/w) ratio. The temperatures achieved resulted in complete mortality of Phragmites rhizomes. In laboratory tests, rhizomes placed in a drying oven at 50ºC for 24 hours, or 55ºC for 12 hours, showed 100% plant mortality. However, under field conditions pile temperatures could not be maintained long enough for the sludge to meet the USEPA 503 biosolids time-temperature pathogen rule requirements for unrestricted land application, even though sample fecal coliform counts did meet regulatory limits.Peer reviewed
DFT simulation of the physical properties of the newly discovered Ti₃Co₅B₂ -type novel borides Mn₃₋ₓ {Rh,Ir}₅B₂ using HPC in addition to X-ray single crystal and TEM data evaluation
No full textBoron has unique chemical properties and with it´s ability of reactions with metals boron yields to a large class of metal borides with high melting points and super hardness [1,2]. Some metal borides are superconductors and there are many borides with extraordinary magnetic properties [3].
While investigating the phase relations in the Mn-{Rh,Ir }-B system we have discovered for both systems a ternary compound, Mn(3−x){Rh,Ir}5B2. The crystal structure of both compounds were determined from X-ray single crystal data to be isotypic with the Ti3Co5B2-type (space group P4/mbm, No. 127). Remarkably, both cases exhibit a significant defect at the Mn 2a sites, which is at the origin of the unit cell.
The absence of a superstructure related to these defects is confirmed by transmission electron microscopy studies, in fact Mn atoms and their corresponding vacancies randomly share the 2a sites in a small unit cell.
The aim of this presentation is to show that we can model this randomly occurring vacancies of Mn atoms in the above mentioned crystallographic positions with large supercell simulations. We initially perform a
full relaxation of the lattice parameters and ionic positions for the unit cell with no vacancies followed by supercell calculations with cells as large as 2 × 2 × 3, which results in a 240 atoms structure. The effect of the Mn vacancies is then simulated by running calculations with some Mn atoms removed from the 2a site (out of 24).
To run simulations on such big supercells we needed the aid of high-performance computing (HPC) and, therefore, did our calculations on the Vienna Scientific Cluster (VSC). We have run several tests with the
Vienna ab-initio simulation package VASP, which we have used for our density functional theory (DFT) approach to find out the optimal adjustments for the parallelism settings. The results of this investigation will be presented here.
References
[1] Steiner, S., Rogl, G., Flansdorfer, H., Noel, H., Gonçalves, A.P., Giester, G., and Rogl, P.F., J. Alloy.
Comp. 811, 151578 (2019).
[2] Steiner, S., Rogl, G., Michor, H., Giester, G., Rogl, P.F., and Gonçalves, A.P., Dalton Trans. 47, 12933
(2018).
[3] Ali, T., Steiner, S., Ritter, C., and Michor, H., J. Alloy. Comp. 716, 251 (2017)
Zechariah 9-14 as the substructure of 1 Peter’s eschatological program
No full textThe principal aim of this study is to discern what has shaped the author of 1 Peter to regard Christian suffering as a necessary (1.6) and to-be-expected (4.12) component of faithful allegiance to Jesus Christ. Most research regarding suffering in 1 Peter has limited the scope of inquiry to two particular aspects—its cause and nature, and the strategies that the author of 1 Peter employs in order to enable his addressees to respond in faithfulness. There remains, however, the need for a comprehensive explanation for the source that has generated 1 Peter’s theology of Christian suffering. If Jesus truly is the Christ, God’s chosen redemptive agent who has come to restore God’s people, then how can it be that Christian suffering is a necessary part of discipleship after his coming, death and resurrection? What led the author of 1 Peter to such a startling conclusion, which seems to runs against the grain of the eschatological hopes and expectations of Jewish restoration ideology?
This thesis analyzes the appropriation of shepherd and fiery trials imagery,
and argues that the author of 1 Peter is dependent upon Zechariah 9-14 for his
theology of Christian suffering. Said in another way, the eschatological program of
Zechariah 9-14, read through the lens of the Gospel, functions as the substructure
for 1 Peter’s eschatology and thus its theology of Christian suffering.
In support of this hypothesis, this study highlights the fact that Zechariah 9-
14 was available and appropriated in early Christianity, in particular in the Passion
Narrative tradition; that the shepherd imagery of 1 Pet 2.25 is best understood
within the milieu of the Passion Narrative tradition, and that it alludes to the
eschatological program of Zechariah 9-14; that the fiery trials imagery found in 1
Peter 1.6-7 and 1 Pet 4.12 is distinct from that which we find in Greco-Roman and OT
wisdom sources, and that it shares exclusive parallels with some unique features of
the eschatological program of Zechariah 9-14; that Zechariah 9-14 offers a more
satisfying explanation for the modification of Isa 11.2 in 1 Pet 4.14, the transition
from 4.12-19 to 5.1-4, why Peter has oriented his letter with the term διασπορά,
and why he has described his addresses as οἶκος τοῦ θεοῦ; and finally that 1 Peter
contains an implicit foundational narrative that shares distinct parallels with the
eschatological program of Zechariah 9-14.
We can conclude that 1 Peter offers a unique vista into the way in which at
least one early Christian witness came to understand and to communicate the fact
that Christian suffering was a necessary feature of faithful allegiance to Jesus Christ
A conversation with Thomas Sowell
No full textIn this episode, host Peter Krogh sits down with Thomas Sowell, the prominent black economist and social commentator. Born in North Carolina, Sowell grew up in Harlem. He received a bachelor's degree from Harvard, a master's degree from Columbia and a PhD from the University of Chicago. In 1980, he became the Rose and Milton Friedman Senior Fellow at Stanford University's Hoover Institution. A prolific author, Sowell frequently provoked controversy with his commentary on race and ethnic conflict. In this interview, Dr. Sowell discusses his latest book, The Economics and Politics of Race: An International Perspective, which examines how different races and ethnicities fare in different societies.Host Peter Krogh sits down with economist and social commentator Thomas Sowell to discuss Sowell's latest book The Economics and Politics of Race
Characterization of Wood Mulch and Leachate/Runoff from Three Wood Recycling Facilities
No full textLarge-scale open storage of wood mulch is common practice at wood recycling facilities. During rain and snow melt, leachate with soluble compounds and suspended particles is released from mulch stockpiles. The objective of this study was to determine the quality of leachate/runoff from wood recycling facilities to evaluate its potential to contaminate receiving waterbodies. Wood mulch (n = 30) and leachate/runoff (n = 26) samples were collected over 1.5 years from three wood recycling facilities in New Jersey, USA. Differences by site were found (p < 0.05) for most of the 21 constituents tested in the solid wood mulch samples. Biochemical oxygen demand (range <20 – 3000 mg/L), chemical oxygen demand (134 - 6000 mg/L) and total suspended solids (69 - 401 mg/L) median concentrations of the leachate/runoff samples were comparable to those of untreated domestic wastewater. Total Kjeldahl N, total P and fecal coliform median values were slightly lower than typical wastewater values. Dose-response studies with leachate/runoff samples using zebrafish (Danio rerio) embryos showed that mortality and developmental defects typically did not occur even at the highest concentration tested, indicating low toxicity, although delayed development did occur. Based on this study, leachate/runoff from wood recycling facilities should not be released to surface waters as it is a potential source of organic contamination and low levels of nutrients. A study in which runoff from a controlled drainage area containing wood mulch of known properties is monitored would allow for better assessment of the potential impact of stormwater runoff from wood recycling facilities.Peer reviewe
Allo-triploid Sphagnum <sup>x</sup>falcatulum: single individuals contain most of the Holantarctic diversity for ancestrally indicative markers
No full textBackground and Aims. Allopolyploids exhibit both different levels and patterns of genetic variation than are typical of diploids. However, scant attention has been given to the partitioning of allelic information and diversity in allopolyploids, particularly that among homeologous monoploid components of the hologenome. Sphagnum ×falcatulum is a double allopolyploid peat moss that spans a considerable portion of the Holantarctic. With monoploid genomes from three ancestral species, this organism exhibits a complex evolutionary history involving serial inter-subgeneric allopolyploidizations.
Methods. Studying populations from three disjunct regions (South Island [New Zealand]; Tierra de Fuego archipelago [Chile, Argentia]; Tasmania [Australia]) we examine genetic information for five highly stable microsatellite markers that differ among the three (ancestral) monoploid genomes. We partition the holoploid information into separate components for individuals within and among single sites and regions, as well as within and among the three monoploid genomes, and then convert those information components into corresponding diversity measures.
Key Results. The majority (76%) of alleles detected across these five markers appear to have been captured by hybridization, but the information within each of the three monoploid genomes varied, suggesting a history of recurrent alloploidization between ancestral species containing different levels of genetic diversity. Information within individuals, equivalent to the information among monoploid genomes (for this dataset), was relatively stable, and represented 83% of the grand total information across the Holantarctic, with both inter-regional and inter-population diversification each accounting for about 5% of the total information.
Conclusions. Sphagnum ×falcatulum appears to have inherited the great majority of its genetic diversity at these markers by reticulation, rather than by subsequent evolutionary radiation. However, some post hybridization genetic diversification has become fixed in at least one regional population. Methodology allowing statistical analysis of any ploidy level is presented.Peer reviewed
Der Wahrheitssucher : su Peter Weiss, Dante e l’utopia
No full textThe contribution outlines the utopian dimension of the work and aesthetics of the German-Jewish-Swedish author Peter Weiss (1916-1982), focusing mainly on his "DC-Projekt", the plan of a political rewriting of Dantes' Divine Comedy for the modern stage (1960s). The contribution contends that the medieval poet, called "the truthsearcher" in the posthumous drama "Inferno", is the key figure of the author's utopian concern in his lifelong alternation of autobiographical, poetical and political issues
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