A mixture of silicon carbide nano-particles and nano-whiskers has been synthesized through solid state reduction of silica by graphite employing high energy planetary ball milling for 25 h and subsequent heat treatment at 1300-1700°C in dynamic argon atmosphere. Effects of process conditions on the thermal behavior, phase composition and morphology of the samples were investigated using DTA/TGA, XRD and SEM, technique, respectively. DTA/TGA analysis shows that silicon carbide starts to form at ~ 1250°C. Analysis of the XRD patterns indicates that the phase composition of the sample heat treated at 1300°C for 2 h mainly consists of SiO2 together with small amount of β-SiC. Nano-crystalline silicon carbide phase with a mean crystallite size of 38 nm was found to be dominate phase on heat treatment temperature at ~ 1500°C. Substantial SiO2 was still remained in the above sample. SEM studies reveal that the sample heat treated at 1500°C for 2 h contains nano-particles and nano-whisker of β-SiC with a mean diameter of almost ~ 85 nm. The results obtained were also showed that the characteristics of the synthesized SiC particles strongly depend on the mechanical activation and heat treatment conditions.

The Survey of oral-dental health of elementary ... [21] Effect of a training intervention program ... [22] Utilizing the health promotion model to predict oral ... [23] The effect of oral health education based on health ... [24] The effect of education based on health belief model ... [25] Oral health care based on educational health ... [26] Prediction of dental caries preventive behaviors ... [27] Prediction of oral health in children 3-6 ... [28] Predictors of oral health promotion behaviors ... [29] The Role of Self-Efficacy and Factors Related ... [30] Planning and evaluation of an educational intervention program ... [31] Determinants of oral health behavior among high school students ... AimsOral problems, particularly dental caries, are among prevalent health problems across the world that normally initiate in adolescence. This study aimed to determine oral healthrelated factors based on the health belief model among 10th to 12th-grade students in Kashan.Instrument & Methods This cross-sectional study was conducted on 180 10th to 12th-grade students living in Kashan City, Iran, in 2017-18. Using multistage sampling, students were randomly selected from schools. Then, students completed a valid and reliable researchermade questionnaire. Utilizing independent t-test, logistic regression, ANOVA, and Pearson's correlation coefficient, the collected data were analyzed by SPSS 20. Findings 50.6% of the participants brushed teeth at least once a day, 20% used dental floss once a day, and 8.3% referred to the dentist once every six months. There was a significant positive correlation between perceived self-efficacy and oral health behaviors (r=0.35; p<0.001). In addition, perceived barriers had a significant negative relationship with oral health behaviors (r=-0.30; p<0.001). However, perceived susceptibility, perceived severity, and perceived benefits had no significant correlation with oral health behaviors (p>0.05). Conclusions The health belief model has the necessary effectiveness in promoting oral health behaviors. It is suggested to utilize appropriate plans and educational interventions based on behavioral models and theories to increase self-efficacy and remove barriers to toothbrushing behavior, utilization of dental floss, and improvement of oral health in students.