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Structure of the copper tripodal Schiff base complex {tris[4-(2-thienyl)-3-aza-κN-3-butenyl]amine-κN}copper(I) tetrafluoroborate
The copper Schiff base complex {tris[4-(2-thienyl)-3-
aza-~N-3-butenyl]amine-~N} copper(I) tetrafluoroborate,
[Cu{N(CTHgNS)3 }]+.BF4- (I), crystallizes with the cation
residing in a general position and two disordered tetrafluoroborate
anions residing on twofold axes. The cation
has approximate threefold symmetry and the copper(I)
geometry is distorted trigonal pyramidal with coordination
from the apical tertiary amine N atom and the three
azomethine N atoms but not from the S atoms of the three
thiophene moieties. The principal bond lengths are Cu--
Napical 2.300 (5) ,~ and mean Cu--Nequatorial 1.994 (4) A,,
with a mean Cu-..S contact of 3.270 (2) A
Utopia, The Kingdom of God and Heaven: Utopian, Social Gospel and Gates Ajar Fiction
Utopia, The Kingdom of God and Heaven: Utopian, Social Gospel and Gates Ajar Fictio
Dual Fronts Propagating into an Unstable State
The interface between an unstable state and a stable state usually develops a
single confined front travelling with constant velocity into the unstable
state. Recently, the splitting of such an interface into {\em two} fronts
propagating with {\em different} velocities was observed numerically in a
magnetic system. The intermediate state is unstable and grows linearly in time.
We first establish rigorously the existence of this phenomenon, called ``dual
front,'' for a class of structurally unstable one-component models. Then we use
this insight to explain dual fronts for a generic two-component
reaction-diffusion system, and for the magnetic system.Comment: 19 pages, Postscript, A
Poetry's politics in archaic Greek epic and lyric
In a recent book (Elmer 2013) examining the representation of collective decision making in the Iliad, I have advanced two related claims: first, that the Iliad projects consensus as the ideal outcome of collective deliberation; and second, that the privileging of consensus can be meaningfully correlated with the nature of the poem as the product of an oral tradition.2 The Iliad's politics, I argue, are best understood as a reflection of the dynamics of the tradition out of which the poem as we know it developed. In the course of the present essay, I intend to apply this approach to some of the other texts and traditions that made up the poetic ecology of archaic Greece, in order to illustrate the diversity of this ecology and the contrast between two of its most important "habitats," or contexts for performance: Panhellenic festivals and the symposium. I will examine representative examples from the lyric and elegiac traditions associated with the poets Alcaeus of Mytilene and Theognis of Megara, respectively, and I will cast a concluding glance over the Odyssey, which sketches an illuminating contrast between festival and symposium. I begin, however, by distilling some of the most important claims from my earlier work in order to establish a framework for my discussion.In memoriam John Miles Fole
I. Wind damage to Iowa farm buildings, II. The design of the bent rafter to resist wind loads
Revealing the pure confinement effect in glass-forming liquids by dynamic mechanical analysis
Many molecular glass forming liquids show a shift of the glass transition Tg
to lower temperatures when the liquid is confined into mesoporous host
matrices. Two contrary explanations for this effect are given in literature:
First, confinement induced acceleration of the dynamics of the molecules leads
to an effective downshift of Tg increasing with decreasing pore size. Secondly,
due to thermal mismatch between the liquid and the surrounding host matrix,
negative pressure develops inside the pores with decreasing temperature, which
also shifts Tg to lower temperatures. Here we present novel dynamic mechanical
analysis measurements of the glass forming liquid salol in Vycor and Gelsil
with pore sizes of d = 2.6, 5.0 and 7.5 nm. The dynamic complex elastic
susceptibility data can be consistently described with the assumption of two
relaxation processes inside the pores: A surface induced slowed down relaxation
due to interaction with rough pore interfaces and a second relaxation within
the core of the pores. This core relaxation time is reduced with decreasing
pore size d, leading to a downshift of Tg in perfect agreement with recent DSC
measurements
Tests on Thin-walled Celluloid Cylinders to Determine the Interaction Curves Under Combined Bending, Torsion, and Compression or Tension Loads
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