Identification of heavy metal origins related to chemical and morphological soil properties using several non-destructive X-ray analytical methods

PubMed: 22722978Soils are complex mixtures of organic, inorganic materials, and metal compounds from anthropogenic sources. In order to identify the pollution sources, their magnitude and development, several X-ray analytical methods were applied in this study. The concentrations of 16 elements were determined in all the soil samples using energy dispersive X-ray fluorescence spectrometry. Soils of unknown origin were observed by scanning electron microscopy equipped with a Si(Li) X-ray detector using Monte Carlo simulation approach. The mineralogical analyses were carried out using X-ray diffraction spectrometry. Due to the correlations between heavy metals and oxide compounds, the samples were analyzed also by electron probe microanalyzer (EPMA) in order to have information about their oxide contents. On the other hand, soil pH and salinity levels were identified owing to their influence between heavy metal and soil-surface chemistry. Moreover, the geoaccumulation index (I geo ) enables the assessment of contamination by comparing current and pre-industrial concentrations. © 2012 Springer Science+Business Media B.V

Changes of surface properties of calcite particles with calcium stearate using conventional experimental design and properties of coated calcite

Calcite is utilized as a filler mineral in the industries such as plastics, rubber, and paint, to gain products with a variety of features. In order to use a calcite ore as a filler, some specific physical and physico-chemical properties are required such as ultra-fine sizes and conversion of hydrophilic to hydrophobic structure. In the present study, for these purposes, surfaces of the ultra-fine calcite powder (d50=2.94 μm) were coated by a mechano-chemical process with calcium stearate [Ca(C17H35COO)2] in a stirred ball mill. The influence of operating parameters such as calcite filling-ratio, ball-filling ratio, operation speed, grinding time and chemical dosage on the active ratio (%) was systematically examined. Then, the properties of modified calcite product were measured and evaluated by contact angle, TGA, DTA, FTIR, and SEM. The results showed that the mechano-chemical technology is very effective for modifying the surface of micronized calcite products using calcium stearate chemical

Change from health center to family physician period in the Turkish health system: A qualitative study

Introduction Health care reforms in Turkey have been implemented resolutely in the last 12 years. The shift from health center (HC) to a family physician (FP) approach is 1 of the basic interventions of these reforms. The goal of the current study is to evaluate opinions of patients, health care workers, and managers, using qualitative methods. Methods In-depth interviews were conducted with patients who received health care services in both the FP and the HC periods, and with health care workers and managers in health care facilities that served in both periods. The interviews were recorded after obtaining permission, and then transcribed. Both health care staff that worked in the 2 periods and the patients that received health care services in the 2 periods reported that FP system was superior to HC system in attention showed by the family physicians, being followed by the same physician, and having confidence in physicians. Results The current FP period is superior to HC in facilities such as patient records, computer, internet, and phone. The strengths of HC period include home visits, environmental health studies, and family planning services. According to health care workers who worked in the 2 periods, HC was superior to FP in team spirit, public service delivery, and surveillance of communicable diseases. Conclusion Public service delivery and environmental health studies and primary care practice in rural areas must be scrutinized in the context of the FP approach