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61.
Craig F Ferris Tara Stolberg Praveen Kulkarni Murali Murugavel Robert Blanchard D Caroline Blanchard Marcelo Febo Mathew Brevard Neal G Simon 《BMC neuroscience》2008,9(1):111
Background
With the advent of functional magnetic resonance imaging (fMRI) in awake animals it is possible to resolve patterns of neuronal activity across the entire brain with high spatial and temporal resolution. Synchronized changes in neuronal activity across multiple brain areas can be viewed as functional neuroanatomical circuits coordinating the thoughts, memories and emotions for particular behaviors. To this end, fMRI in conscious rats combined with 3D computational analysis was used to identifying the putative distributed neural circuit involved in aggressive motivation and how this circuit is affected by drugs that block aggressive behavior. 相似文献62.
Bogdan Marciniec Mariusz Lewandowski 《Journal of polymer science. Part A, Polymer chemistry》1996,34(8):1443-1445
Acyclic diene polymerization (ADP) of divinyldimethylsilane in the presence of ruthenium RuCl2(PPh3)3 and rhodium [RhCl(cod)]2 catalysts led predominantly to linear silylene-vinylene oligomers (Mn = 1510 and Mw/Mn = 1.19) if the ruthenium catalyst was used or to mixture of cyclic and linear oligomers if rhodium complex was catalyst. © 1996 John Wiley & Sons, Inc. 相似文献
63.
64.
First-principles calculations are presented for the layered perovskite Ca3Mn2O7. The results reveal a rich set of coupled structural, magnetic, and polar domains in which oxygen octahedron rotations induce ferroelectricity, magnetoelectricity, and weak ferromagnetism. The key point is that the rotation distortion is a combination of two nonpolar modes with different symmetries. We use the term "hybrid" improper ferroelectricity to describe this phenomenon and discuss how control over magnetism is achieved through these functional antiferrodistortive octahedron rotations. 相似文献
65.
Llewellyn H. Jones Burton J. Krohn R.Craig Kennedy 《Journal of Molecular Spectroscopy》1978,70(2):288-293
The vibration-rotation spectra of the ν4 fundamental of 12CF4, 13CF4, and 14CF4 have been observed with 0.06 cm?1 resolution. A least squares fit of the data has been used to evaluate the pertinent molecular constants. The band centers are 631.199, 629.285, and 627.348 cm?1 for 12CF4, 13CF4, and 14CF4, respectively. The Coriolis constant ζ4 has been estimated for the three isotopes. 相似文献
66.
We review recent structural studies that we have undertaken aimed at elucidating the fundamental properties of metal-organic
framework materials and their interactions with hydrogen. We have shown that exposing coordinatively unsaturated metal centers
can greatly enhance the hydrogen binding energy and that they result in a significant increase of the surface packing density
of adsorbed hydrogen molecules on materials’ surface. We will review some of the structural aspects of these materials, especially
the adsorbed hydrogen molecule surface packing density in one type of metal-organic framework, MOF-74, which can be packed
even denser than that in solid hydrogen.
相似文献
67.
Madeleine A. Dallaston Dr. Sevan D. Houston Prof. Craig M. Williams 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(52):11966-11970
With the burgeoning interest in cage motifs for bioactive molecule discovery, and the recent disclosure of 1,4-cubane-dicarboxylic acid impact sensitivity, more research into the safety profiles of cage scaffolds is required. Therefore, the impact sensitivity and thermal decomposition behavior of judiciously selected starting materials and synthetic intermediates of cubane, bicyclo[1.1.1]pentane (BCP), and bicyclo[2.2.2]octane (BCO) were evaluated via hammer test and sealed cell differential scanning calorimetry, respectively. Iodo-substituted systems were found to be more impact sensitive, whereas hydroxymethyl substitution led to more rapid thermodecomposition. Cubane was more likely to be impact sensitive with these substituents, followed by BCP, whereas all BCOs were unresponsive. The majority of derivatives were placed substantially above Yoshida thresholds—a computational indicator of sensitivity. 相似文献
68.
The UV absorption spectra of six structurally related derivatives of anisole and veratrole, i.e., anisaldehyde, (E)-anethole, estragole, veratraldehyde, methyleugenol and (E)-methylisoeugenol, were recorded at various concentrations of the anionic surfactants, either sodium lauryl sulfate (SLS) or sodium lauryl ether sulfate (SLES) at T = 298 K. In addition, conductivity and density measurements were made for the SLS and SLES solutions to determine the volumetric properties of the studied surfactants. Next, using the W. Al-Soufi, L. Pińeiro and M. Novo model (APN model) including the pseudo-phase model for micellar solubilization, the values of micelle-water partition coefficients for each perfume-surfactant system were determined. In addition, the relations between the molecular structures of the solute and the head group of the surfactant and the value of the micelle-water partition coefficient as well as the octanol-water one were discussed. 相似文献
69.
We consider the Reynolds Averaged Navier–Stokes (RANS) model of order one (u,p,k) set in R3 which couples the Stokes Problem to the equation for the turbulent kinetic energy by k-dependent eddy viscosities in both equations and a quadratic term in the k -equation. We study the case where the velocity and the pressure satisfy periodic boundary conditions while the turbulent kinetic energy is defined on a cell with Dirichlet boundary conditions. The corresponding eddy viscosity in the fluid equation is extended to R3 by periodicity. Our contribution is to prove that this system has a solution when the eddy viscosities are nondecreasing, smooth, unbounded functions of k, and the eddy viscosity in the fluid equation is a concave function. 相似文献
70.
Let Σn be the symmetric group on n letters. For l ≤ n identify Σl with a subgroup of Σn in the natural way. Let k be an algebraically closed field of characteristic p. This article begins to develop a theory for modules over the centralizer algebras kΣnΣl that is analogous to James's theory of permutation modules, Specht modules, and simple modules over kΣn. We make a conjecture about how to construct all simple kΣnΣl-modules, we develop tools to test the conjecture, and we prove that it is correct for all n when l < p. 相似文献