The evolutionary mechanisms maintaining genetic variation in life span, particularly post-reproductive life span, are poorly understood. We characterized the effects of spontaneous mutations on life span in the rhabditid nematodes Caenorhabditis elegans and C. briggsae and standing genetic variance for life span and correlation of life span with fitness in C. briggsae. Mutations decreased mean ...

Porous graphitic carbon layers encapsulating Ni nanoparticles (Ni@C) were prepared by a facile thermolysis of a Ni-containing metal–organic framework, the structure of which were characterized by power X-ray diffraction (XRD), N2 adsorption–desorption, transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS) in detail. The resulting Ni@C nanocomposites served as highly...

The reaction of NiCl(2)·6H(2)O with sodium 2,2-dicyano-ethene-1,1-dithiol-ate [Na(2)(i-mnt)] in dimethyl sulfoxide produces the title complex, [Ni(C(2)H(6)OS)(6)][Ni(C(4)N(2)S(2))(2)]. There is half each of an [Ni(C(2)H(6)OS)(6)](2-) complex anion and an [Ni{(CH(3))(2)SO}(6)](2+) complex cation in the asymmetric unit. The i-mnt ligand coordinates in a bidentate manner to the Ni atom in the anio...

Carbon spheres and tubes were formed from acetylene decomposition on SBA-15 and Ni-SBA-15 at 650-850 °C. At 650 °C, the decomposed carbons covered the surface of the support, and no carbon spheres and filament materials were formed. Carbon sphere formation occurred at 750 °C-850 °C; with diameters ranging from 0.8 μm-1.1 μm. For Ni-SBA-15, the diameters of the spheres and filaments were 0.8 μm ...

Performance of Ni/Al2O3 catalysts (10 wt.% Ni) in steam reforming of n-butane was investigated in terms of n-butane conversion, selectivity to hydrogen and hydrogen yield. The process was carried out in a fixed-bed tubular reactor at 650 °C and atmospheric pressure. The volumetric flow rates of n-butane and steam were 0.1 mL/min and 0.6 mL/min, respectively. The catalysts were prepared by preci...

In the title compound, [Ni(C(8)H(7)O(3))(C(10)H(8)N(2))]ClO(4), the Ni(II) atom is in a slightly distorted square-planar coordination by two N atoms from the 2,2'-bipyridine (bipy) ligand and two O atoms from the deprotonated 2-formyl-6-methoxy-phenolate (mbd) ligand. The bipy ligand is nearly coplanar with the Ni(II) square plane, the Ni atom being only 0.042 (2) Å from the mean plane, whereas...

The title compound, [Ni(C(18)H(30)FO(2)P(2))(C(3)H(4)N(2))]PF(6), was prepared by halide abstraction with TlPF(6) in the presence of CH(3)CN in CDCl(3) from the respective neutral pincer chlorido analogue followed by addition of pyrazole. The PO-C-OP pincer ligand acts in typical trans-P(2) tridentate fashion to generate a distorted square-planar nickel structure. The Ni-N(pyrazole) distance is...

The title compound, [Ni(C(4)H(13)N(3))(2)][Ni(C(4)N(2)S(2))(2)], has been synthesized by the reaction of Ni(ClO(4))(2)·6H(2)O, diethyl-enetriamine (deta) and Na(2)[Ni(mnt)(2)] [mnt = maleonitrile-dithiol-ate(2-)] in methanol. The structure is composed of a [Ni(deta)(2)](2+) cation and a [Ni(mnt)(2)](2-) anion. The coordination geometry of the Ni(II) ion in the cation is slightly distorted octa-...

In order to examine whether catalyst granular size was a factor for tar removal and syngas composition enhancement, three Ni/char catalysts with 90-100 mesh (Ni/SC), 50-60 mesh (Ni/MC), and 20-30 mesh (Ni/LC) size were prepared with a mechanical mixing method and tested in an updraft gasifier. Reforming parameters investigated were the reaction temperature (650-850C), the Ni loading (5-20% of ...