Formation of nickel-thiolate aggregates via reaction with CH2Cl2

Reaction of the mononuclear nickel-thiolate complex [Ni(L-1)(dppe)] with CH2Cl2 affords the novel pentanuclear complex Ni5Cl2(L-1)(4)(dppe)(2)], while [Ni(L-1)(dcpe)] reacts with CH2Cl2 to give the binuclear species [Ni2Cl2(L-2)(dcpe)(2)] in which two L-1 units are linked by a methylene group derived from CH2Cl2.

Microstructure and mechanical properties of low nickel maraging steel

Austenitization with lower temperature and intercritical annealing were introduced in the treatment of a maraging steel with a composition of Fe–12.94Ni–1.61Al–1.01Mo–0.23Nb (wt.%). Scanning electron microscopy was employed to study the microstructure after austenitization at 950 °C and intercritical annealing, followed by aging at 485 and 600 °C. X-ray diffraction (XRD) analysis was applied to evaluate the formation of retained or reverted austenite. Thermodynamic calculation was employed to calculate equilibrium phase mole fractions. Hardness and Charpy impact toughness of the steel were measured. Intercritical annealing treatments did not result in significant increase of hardness either before or after aging. The Charpy impact toughness of the alloy in aged condition was enhanced after austenitization at 950 °C. No austenite was observed in XRD. However, suspected reverted austenite was found after austenitization at 950 °C followed by aging at 600 °C for 4 h. Relationships among heat treatment, microstructure and mechanical properties are discussed.

Effect of Inhibitor Compounds on N-epsilon-(Carboxymethyl)lysine (CML) and N-epsilon-(Carboxyethyl)lysine (CEL) Formation in Model Foods

The possible adverse effects on health of diet-derived advanced glycation endproducts (AGES) and advanced lipoxidation endproducts (ALES) is of current interest. This study had the objective of determining the effects of the addition of AGE/ALE inhibitors and different types of sugar and cooking oil on N-epsilon-(carboxymethyl)lysine (CML) and N-epsilon-(carboxyethyl)lysine (CEL) formation in model foods (sponge cakes). The cake baked using glucose produced the highest level of CML (2.07 +/- 0.24 mmol/mol lysine), whereas the cake baked using fructose produced the highest concentration of CEL (25.1 +/- 0.15 mmol/mol lysine). There were no significant differences between CML concentrations formed in the cakes prepared using different types of cooking oil, but significant differences (P

The comparative solvatochromism of arylazo and heteroarylazo compounds based on N,N-diethyl-m-acetylaminoaniline and N,N-diethyl-m-toluidine

Azobenzene dyes derived from various anilines and aminothiaheterocycles ate-coupled with commercially important N,N-diethyl-m-toluidine (T series) and iv,N-diethyl-m-acetylaminoaniline (A series) are positively solvatochromic. The visible spectra of 16 pairs of derivatives have been measured in up to 22 solvents, and the transition energies related to Kamlet-Taft solvent polarity parameters. In general, A-series dyes are more bathochromic than their T-series counterparts in nonpolar solvents, consistent with colour chemistry tradition, However, in more dipolar solvents the more bathochromic T-series representatives unexpectedly become more bathochromic than their A-series partners. The relative solvatochromic shifts of the A and T series are related to their respective dipole moments, These in turn are distinguished by the effect of the anilide carbonyl group dipole moment, which is antiparallel to, and thus reduces, the dipole moment of the chromogen.

Use of luminescent gold compounds in the design of thin-film oxygen sensors

The use of two gold compounds incorporated into thin plastic films as luminescence quenching oxygen sensors is described. The films are sensitive both to gaseous oxygen and to oxygen dissolved in nonaqueous media such as ethanol. The luminescence quenching of these sensors by oxygen obeys the Stern-Volmer equation and Stern-Volmer constants of 5.35 x 10(-3) and 0.9 x 10(-3) Torr(-1) are found, respectively, for the two dyes in a polystyrene polymer matrix. The sensitivity of the films is strongly influenced by the nature of the polymer matrix, and greatest sensitivity was found in systems based an the polymers polystyrene or cellulose acetate butyrate. Sensitivity was not found to be temperature dependent though raising the temperature hom 15 to 50 degrees C did result in a slight decrease in emission intensity and a hypsochromic shift in the emission wavelength. The rate of response and recovery of the sensors can be increased either by decreasing film thickness or by increasing the operating temperature. The operational and storage stability of these films is generally good though exposure to light should be avoided as one of the dyes tends to undergo photobleaching probably due to a photoinduced ligand substitution reaction.