265 research outputs found
Noise in Genotype Selection Model
We study the steady state properties of a genotype selection model in
presence of correlated Gaussian white noise. The effect of the noise on the
genotype selection model is discussed. It is found that correlated noise can
break the balance of gene selection and induce the phase transition which can
makes us select one type gene haploid from a gene group.Comment: 8 pages, 4 figure
Current Reversals in a inhomogeneous system with asymmetric unbiased fluctuations
We present a study of transport of a Brownian particle moving in periodic
symmetric potential in the presence of asymmetric unbiased fluctuations. The
particle is considered to move in a medium with periodic space dependent
friction. By tuning the parameters of the system, the direction of current
exhibit reversals, both as a function of temperature as well as the amplitude
of rocking force. We found that the mutual interplay between the opposite
driving factors is the necessary term for current reversals.Comment: 9 pages, 7 figure
3-(5-Chloronaphthalene-1-sulfonamido)-2-(2-hydroxyethyl)-4,5,6,7-tetrahydro-2H-pyrazolo[4,3-c]pyridin-5-ium chloride
In the cation of the title compound, C18H20ClN4O3S+·Cl−, the tetrahydropyridinium ring assumes a half-chair conformation. The dihedral angle between the pyrazole ring and the naphthalene ring system is 75.19 (6)°. In the crystal, ions are linked into a three-dimensional network by N—H⋯O, N—H⋯Cl and O—H⋯Cl hydrogen bonds and weak π–π stacking interactions with centroid–centroid distances of 3.608 (2) Å
Bis[4-(2-hydroxybenzylideneamino)benzoato-κO 1]tetrakis(methanol-κO)cadmium
In the title mononuclear complex, [Cd(C14H10NO3)2(CH3OH)4], the Cd2+ cation is situated on an inversion centre. It exhibits a distorted octahedral coordination, defined by two carboxylate O atoms from two monodentate anions and by four O atoms from four methanol molecules. The crystal structure comprises intramolecular O—H⋯O and O—H⋯N, and intermolecular O—H⋯O hydrogen bonds. The latter help to construct a layered structure extending parallel to (100)
5-tert-Butyl 1-ethyl 3-amino-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazole-1,5-dicarboxylate
The asymmetric unit of the title compound, C13H20N4O4, contains two crystallographically independent molecules in which the dihedral angles between the fused pyrrole and pyrazole rings are 5.06 (8) and 1.12 (8)°. In the crystal, molecules are linked by intermolecular N—H⋯O and N—H⋯N hydrogen bonds into chains parallel to the b axis
Poly[[tetrakis(μ-2-anilinobenzoato-κ2 O:O′)tetra-μ1,1,1-azido-tetra-μ1,1-azido-octamethanolhexanickel(II)] methanol hexasolvate]
The crystal structure of the title compound, [Ni6(C13H10NO2)4(N3)8(CH3OH)8]·6CH3OH, consists of a centrosymmetric hexanuclear [NiII
6(C13H10NO2)4(N3)8(CH3OH)8] molecule and six methanol solvent molecules. In the hexanuclear unit, the six octahedrally coordinated NiII atoms are linked by four μ1,1,1-azide and four μ1,1-azide bridges, forming a face-sharing Ni6N8 tetracubane-like unit with four missing corners. The NiII atoms are further bridged by four μ1,2-carboxalate groups. Neighbouring hexanuclear units are connected via N—H⋯O hydrogen-bonding interactions into a three-dimensional structure. Although the H atoms of the methanol OH groups could not be located, O⋯N/O contacts between 2.65 and 2.86 Å suggest that these molecules participate in hydrogen bonding
Dichloridobis[2-(2-furyl)-1-(2-furylmethyl)-1H-benzimidazole-κN 3]cadmium(II)
In the title complex, [CdCl2(C16H12N2O2)2], the CdII ion exhibits site symmetry 2. It shows a distorted tetrahedral coordination defined by two N atoms from symmetry-related 2-(2-furyl)-1-(2-furylmethyl)-1H-benzimidazole ligands and by two symmetry-related Cl atoms. Intramolecular C—H⋯O hydrogen bonds stabilize the molecular configuration. Adjacent molecules are linked through C—H⋯Cl hydrogen bonds into a network structure
catena-Poly[[chloridocadmium(II)]bis{μ-1-[(2-ethyl-1H-imidazol-1-yl)methyl]-1H-benzotriazole}[chloridocadmium(II)]di-μ-chlorido]
In the polymeric title complex, [CdCl2(C12H13N5)]n, the CdII atom is five-coordinated by two N atoms from two bridging 1-[(2-ethyl-1H-imidazol-1-yl)methyl]-1H-benzotriazole (bmei) ligands, two bridging Cl atoms and one terminal Cl atom in a distorted trigonal–bipyramidal geometry. The CdII atoms are connected alternately by the Cl atoms and bmei ligands, leading to a zigzag chain extending parallel to [011]. π–π interactions, with a centroid–centroid distance of 3.3016 (3) Å, help to stabilize the crystal packing
Enormous lithium isotopic variations of abyssal peridotites reveal fast cooling and Melt/Fluid-rock interactions
Author Posting. © American Geophysical Union, 2020. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Solid Earth 125(9),(2020): e2020JB020393, doi:10.1029/2020JB020393.Fast diffusing Li isotopes provide important insights into the “recent” transient events or processes for both modern and ancient times, but questions remain concerning the large Li isotopic variations of mantle peridotites, which greatly hampers their usage as a geochemical tracer. This study investigates in situ Li content and isotopic profiles of the constituent minerals of abyssal peridotites from the Gakkel Ridge and Southwest Indian Ridge. The complicated and large variations of Li isotopic profiles in Clinopyroxene (Cpx) and Orthopyroxene (Opx) indicate Li isotopic disequilibrium at millimeter scale. The negative correlations of a wide range of Li contents (0.5 to 6.5 ppm) and δ7Li values (−10 to +20‰) of olivine, Opx and Cpx grains/relicts, trace element zoning of Cpx, the occurrence of plagioclase, olivine serpentinization along cracks, together with numerical modeling demonstrate the observed Li characteristics to be a manifestation of high‐temperature mineral‐melt Li diffusion during melt impregnation overprinted by low‐temperature mineral‐fluid Li diffusion during dissolution and serpentinization. The preservation of the Li isotopic diffusion profiles requires rapid cooling of 0.3–5°C/year after final‐stage melt impregnation at the Moho boundary, which is consistent with the low temperature at very slow spreadin g ridges caused by conductive cooling. Compared with the well‐studied melt‐rock interaction process, our study indicates that low‐temperature fluid‐rock interaction can induce Li diffusion even in the visibly unaltered mineral relicts of partially altered rocks.This study was financially supported by the National Science Foundation of China (grant no. 41872058) and the U.S. National Science Foundation grant.2021-03-0
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