Evaluation of blends tincal waste, volcanic tuff, bentonite and fly ash for use as a cement admixture.

The evaluation of blends tincal waste (TW), fly ash (FA), bentonite (BE), volcanic tuff (VT) for use as a cement admixture was investigated. The properties examined include setting time, expansion, water requirement, specific surface and compressive strength of cement mixtures. The results revealed that the early compressive strength decrease with increasing tincal waste, due to tincal waste increasing initial setting time of the cement. The tincal waste and volcanic tuff of cement mixtures increased and there was reduction in compressive strength. The more the tincal waste increased the greater retardation there was initial setting time this may be attributed to containing high amount B2O3 and MgO content. The tincal waste and fly ash increased with expansion increased. Water requirement increased as the Blaine fineness of the cement mixtures increased. The results obtained were compared with standards and five batches were advised as suitable for the standard.

The sorption behavior of a nickel-insolubilized humic acid system in a column arrangement.

The sorption characteristics of insolubilized humic acid (IHA) were investigated for Ni (II) in a column arrangement. The sodium form of the IHA (INaA) was used as a solid phase. Column operations were performed with five steps and all of them were monitored continuously by a flowthrough cell-adapted UV-Vis spectrophotometer. Thus, all solid-phase extraction (SPE) steps were visualized by breakthrough curves and analyses progress were evaluated. However, all calculations and evaluations were focused on the atomic absorption spectrophotometric (AAS) analyses of the solutions collected during the stripping steps. There was a high correlation (r(2), 0.972) between peak area and AAS data of stripping steps. The effect of concentration and pH of the loading solution onto sorption of Ni (II) by INaA was investigated. Sorption characteristics were evaluated by using Freundlich, Langmuir, and Dubinin-Radushkevich (D-R) adsorption isotherms, as well as by Scatchard plot analysis. Multilayer sorption was found to be agreeable for Ni (II). From the D-R isotherm the mean free energy of sorption (E) was calculated (6.65 kJ mol(-1)) and attributed to the multilayer sorption. Finally, the sorption characteristic of the INaA-Ni (II) system was compared with that of the INaA-Cu (II) system, and possible separation of two ions in a binary mixture system is discussed.

Differentiation of benign and malignant cervical lymph nodes: value of B-mode and color Doppler sonography.

OBJECTIVE: To evaluate the efficacy of color Doppler sonography in detecting possible differences in blood flow patterns and B-mode sonographic characteristics between malignant and benign cervical lymph nodes. PATIENTS AND METHODS: During a period of 10 months, the palpable cervical lymph nodes of 39 patients were prospectively evaluated with B-mode and color Doppler sonography. The echogenity, contour, ratio of longitudinal diameter to the transverse diameter and the presence of a hilus were evaluated by B-mode sonography. Capsullary and intranodal arterial flow rates were measured and maximal systolic, end-diastolic, mid-systolic flow velocities with pulsatility, resistivity and acceleration indices were obtained. Final diagnosis was established by excisional biopsy (n:34) and clinical follow-up (n:5). RESULTS: The lymph nodes in 20 cases were malignant and in 19 cases were benign. The B-mode contour characteristics and presence of a hilus in malignant and benign lymph nodes were statistically significant (P < 0.05), but there were no significant differences between the ratio of longitudinal diameter to the transverse diameter (P > 0.05), echogenity (P > 0.05) and the diameters of lymph nodes (P > 0.05). Flow patterns were obtained in 14 malignant (70%) and 10 benign (52.6%) cases. The maximal systolic, end diastolic, mid-systolic flow velocities and pulsatility, resistivity, acceleration indices did not differ statistically (P > 0.05). CONCLUSION: In the differentiations of benign and malignant cervical lymph nodes, the B-mode and color Doppler sonography are limited methods and can not replace biopsy.