The effect of solidification behavior on the microstructures and mechanical properties of Ni-Cr-Fe superalloy investment casting is given. Metallographic and image analysis have been used to quantitatively examine the microstructures' evolution. For the parts with the thickness of 3 mm and 24 mm, the volume fraction and maximum equivalent radius of the Laves phase increases from 0.3% to 1.2%, f...

introduction: parent materials as one of the main soil formation factors have a great impact on the concentration of heavy metals in the soil. heavy metals are released to the soil during weathering and pedogenic processes. ultrabasic rocks are known as the potential natural source of heavy metals, especially ni, cr and mn in the soil. average concentrations of ni and cr in the soils are 84 and...

The iron-dependent regulator (IdeR) is a 230-amino acid transcriptional repressor that regulates iron homeostasis, oxidative stress response and virulence in Mycobacterium tuberculosis. The natural ligand for IdeR is Fe(II), but Ni(II), Co(II), Cd(II), Mn(II), and Zn(II) also bind to and activate the protein in vitro. Protein activation by metal is a complex process involving metal-induced fold...

The title compound [Ni(2)(C(6)H(6)O(6)P(2))(2)(C(24)H(16)N(6))(H(2)O)(4)]·2H(2)O or [Ni(2)(tpyprz)(1,3-HO(3)PC(6)H(4)PO(3)H)(2)(H(2)O)(4)]·2H(2)O [tpyprz = tetra-kis-(2-pyrid-yl)pyrazine, C(24)H(16)N(6)] is a binuclear complex with a crystallographic inversion center located at the center of the pyrazine ring. The equivalent nickel(II) sites exhibit a distorted {NiO(3)N(3)} octa-hedral coordina...

High resolution (R = 60 000), high S/N spectra have been obtained for 13 halo stars and 16 disk stars with 5400 <∼ Teff <∼ 6500 K, 4.0 <∼ logg <∼ 4.6 and overlapping metallicities in the range −1.3 <∼ [Fe/H] <∼ −0.5. Equivalent widths of weak Fe i and Fe ii lines are used to determine differential values of Teff and logg. Relative abundances of O, Na, Mg, Si, Ca, Ti, Cr, Fe, Ni, Y andBa are det...

The spatial coherence of a 13.2 nm transient collisional Ni-like Cd soft X-ray laser pumped at 23 degrees grazing incidence was measured in a series of Young's double-slit experiments. We observed pronounced fringe visibility variations associated with microstructures in the beam's intensity profile. The transverse coherence length was measured to be about 1/20 of the beam diameter and did not ...

High-field susceptibility XHF in Fe and Ni (at 4.2, 77, and 300 K) and high-field Mossbauer studies in Fe at 4.2°K are reported and related to the band structure of Fe and Ni and to band models of ferromag­ netism. The Mossbauer effect was employed to measure the change in the hyperfine field H n at the 57Fe nucleus with application of an external field. Assuming H n to be proportional to the b...

Solutions of Rh2(OAc)4 and Et4N[Cp*Ir(CN)3] react to afford crystals of the one-dimensional coordination solid [Et4N[Cp*Ir(CN)3][Rh2(OAc)4]]. This reaction is reversed by coordinating solvents such as MeCN. The structure of the polymer consists of helical anionic chains containing Rh2(OAc)4 units linked via two of the three CN ligands of Cp*Ir(CN)3-. Use of the more Lewis acidic Rh2(O2CCF3)4 in...