In this work a study of the influence of cutting speed and feed on different geometric deviations (straightness, parallelism, roundness, and circular run-out) of dry turned UNS A97075 (Al-Zn) cylindrical bars has been carried out. The experimental data have revealed a low sensitivity to change of these deviations with cutting speed and feed, within the range of cutting parameters evaluated. In addition, several parametric models have been developed from the experimental results. These models allow predicting the behavior of these deviations as a function of cutting parameters applied. In order to do this, different parametric models (potential, exponential, and polynomial) have been tested. For all analyzed geometric deviations, the exponential model has shown the best fit to the experimental data.

The Ti6Al4V alloy is included in the group of difficult-to-cut materials. Segmented chips are generated for a wide range of cutting parameters. This kind of chip geometry leads to the periodic variation of machining forces, tool vibrations, and work part-tolerance inaccuracies. Therefore, the analysis of chip morphology and geometry becomes a fundamental machinability criterion. However, few studies propose experimental parametric relationships that allow predicting chip-geometry evolution as a function of cutting parameters. In this work, an experimental analysis of the influence of cutting speed and feed rate on various chip-geometric parameters in dry machining of the Ti6Al4V alloy was carried out. In addition, the chip morphology and chip microstructure were studied. A clear dependence of certain chip-geometric parameters on the cutting parameters studied was found. From the experimental data, several parametric relationships were developed. These relationships were able to predict the evolution of different geometric parameters as a function of cutting speed and feed, within the tested range of values. The differences between the proposed models and the experimental data were also highlighted. These parametric equations allowed quantifying the value of parameters in which the trend was clear.

Interactions of a widely used commercial anionic surfactant, linear alkylbenzene sulfonate, with zein protein, a water insoluble protein, was studied to better understand the effects of the counterion on skin irritation of anionic surfactants. The neutralizing ions used were inorganics: Li+, Na+, K+, Mg2+, and NH4+ and organics: monoethanolamine, diethanolamine, and triethanolamine. According to the results obtained, the influence of counterions of anionic surfactants on zein solubilization is significant; with magnesium counterions showing lower zein solubilization. In aqueous solutions, zein solubilization by anionic surfactant is related to the effect of the counterion on the critical micelle concentration of the surfactant for the inorganic counter‐ions; for the organic counter‐ions, effects of tighter anionic binding in the micelle also contribute to zein solubilization trends.

No abstract

Sulfoxidation of fatty methyl esters with SO 2 , O 2 , and ultraviolet light of appropriate wavelength has led to a synthesis of sodium methyl ester sulfonates known as Φ-MES. The designation of Φ refers to the random positioning of SO 3 in the alkyl chain. This investigation describes for the first time the operating conditions necessary to produce these new anionic surfactants as well as the analytical methods used in their isolation, analysis, identification. Some surface properties are discussed as well. JSD 1, 335-341 (1998). FIG. 1. Infrared spectra of sodium methyl ester sulfonates (Φ-MES, -) and of α-sulfo fatty methyl esters (α-MES, -·-·-) with C16 chain lengths.