The study on temper embrittlement and hydrogen embrittlement of a test block from a 3Cr1Mo1/4V hydrogenation reactor after ten years of service was carried out by small punch test (SPT) at different temperatures. The SPT fracture energy Esp (derived from integrating the load-displacement curve) divided by the maximum load (Fm) of SPT was used to fit the Esp/Fm versus-temperature curve to determ...

A series of tri- and dimetallic metal complexes of pyridine dicarboxamide cryptates are reported in which changes to the base and metal source result in diverse structure types. Addition of strong bases, such as KH or KN(SiMe3)2, followed by divalent metal halides allows direct access to trinuclear complexes in which each metal center is coordinated by a dianionic N,N,N-chelate of each arm. The...

A series of coordination compounds have been prepared with tridentate Schiff base ligands, 2 ethyl-[(hydroxy propyl)]3, 1 (4H) quinazoline4-semicarbazone [EHPQS) and 2-ethyl-[(hydroxy propyl)]3, 1 (4H) quinazoline4-thiosemicarbozone [EHPQT]. The obtained complexes were characterized by molar mass, elemental analysis, infrared spectra, electronic spectra, magnetic susceptibility molar conductanc...

Most studies of the roles of catalytic metal ions in ribozymes have focused on inner-sphere coordination of the divalent metal ions to the substrate or ribozyme. However, divalent metal ions are strongly hydrated in water, and some proteinenzymes, such as Escherichia coli RNase H and exonuclease III, are known to use metal cofactors in their fully hydrated form [Duffy, T. H., and Nowak, T. (198...

is a new fluorescent thymidine mimic composed of 2'-deoxyuridine fused to dimethylaniline. exhibits the same pKa and base pairing characteristics as native thymidine residues, and its fluorescence properties are highly sensitive to nucleobase ionization, base pairing and metal binding.

One of the primary reasons for the development of base metal alloys for dental applications has been the escalating cost of gold throughout the 20th century. In addition to providing lower cost alternatives, these nonprecious alloys were also found to provide better mechanical properties and aesthetics for some oral applications. Additionally, certain base metal alloy systems are preferred beca...

Metal base pairs of Ag(I) cations and 1-methylthymine (1MT) or deprotonated 1-methylthymine (1MT-H) are produced and analyzed by electrospray ionization mass spectrometry (ESI-MS). Mass-selected ions of type [Ag2(1MT)(1MT-H)](+) and [Ag3(1MT-H)2](+) are interrogated by infrared multiple-photon dissociation (IRMPD) in an ion trap in the range of 1200-3700 cm(-1). Supporting spectroscopic data we...

Quantification of infrared (IR) radiation is a convenient, noncontact method for making the base metal temperature measurements needed for on-line feedback controls. However, the problem of interference from the arc is a complicating factor in applying IR temperature sensing to welding. The objective of this research is to implement and test a top-face, noncontact temperature measurement system...

In order to study MIG welding process of aluminum alloy with longitudinal magnetic field, thermal efficiency with longitudinal magnetic field was analyzed, as well as softening behavior of heat-affected zone (HAZ) and base metal were investigated. The results showed that under the action of longitudinal magnetic field, welding current decreased and resultingly total heat input reduced as the ex...