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Aim: A study was conducted in mid hill region of Jammu district, J&K to analyze the impact lockdown amid covid-19 pandemic on weather parameters so as to define it as a tool to mitigate the pace of climate change. Methodology: Day and night temperature readings were recorded fortnightly during 22nd March to 10th June 2020 from maximum and minimum thermometer, relative humidity from dry and wet bulb thermometers in stevenson screen, rainfall values from ordinary rain gauge, evaporation readings from pan evaporimeter and soil temperature at different depth from soil thermometers. Results: After analyzing the data statistically using “Descriptive statistics” in MS-Excel 2010, it was observed that after the implementation of lockdown and with the beginning of unlock down the change in day temperature was -8.07% from normal mean value, night temperature was -4.44% from normal mean value, rainfall pattern was 30.00% more from normal mean value, Relative Humidity (morning) pattern was 6.94% more from normal mean value, relative humidity (evening) pattern was 20.94% more from normal mean value, evaporation pattern was 7.66% more from normal mean value. The average change in soil temperature in morning at 5 cm, 10 cm and 20 cm depth was -3.46%, -3.84% and -7.23% as compared to year 2019 (22nd March to 10th June 2019) mean value and the change in soil temperature in evening at same depths was -7.69%, -6.31% and -4.14% from year 2019 (22nd March to 10th June 2019). Conclusion: With the variable significant pattern observed in almost all parameters, it can be concluded that lockdown might be an effective tool in mitigating pace of climate change in future.
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OBJECTIVES: This study determined the effect of the air-stream application time and the bonding technique on the dentin bond strength of adhesives with different solvents. Furthermore, the content and volatilization rate of the solvents contained in the adhesives were also evaluated. MATERIALS AND METHODS: Three adhesive systems with different solvents (Stae, SDI, acetone; XP Bond, Dentsply De Trey, butanol; Ambar, FGM, ethanol) were evaluated. The concentrations and evaporation rates of each adhesive were measured using an analytical balance. After acid-etching and rinsing, medium occlusal dentin surfaces of human molars were kept moist (conventional) or were treated with 10% sodium hypochlorite for deproteinization. After applying adhesives over the dentin, slight air-stream was applied for 10, 30 or 60 sec. Composite cylinders were built up and submitted to shear testing. The data were submitted to ANOVA and Tukey's test (alpha = 0.05). RESULTS: Stae showed the highest solvent content and Ambar the lowest. Acetone presented the highest evaporation rate, followed by butanol. Shear bond strengths were significantly affected only by the factors of 'adhesive' and 'bonding technique' (p < 0.05), while the factor 'duration of air-stream' was not significant. Deproteinization of dentin increased the bond strength (p < 0.05). Stae showed the lowest bond strength values (p < 0.05), while no significant difference was observed between XP Bond and Ambar. CONCLUSIONS: Despite the differences in content and evaporation rate of the solvents, the duration of air-stream application did not affect the bond strength to dentin irrespective of the bonding technique.
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Humanos , Acetona , Adhesivos , Recubrimiento Dental Adhesivo , Dentina , Recubrimientos Dentinarios , Diente Molar , Hipoclorito de Sodio , Solventes , VolatilizaciónRESUMEN
AIM: To investigate law of vacuum drying process and provide basic technical supports for drying process and design of drying machine. METHODS: A batch-drying experiment system was used to continuously record the mass and temperature of the drying sample,then the key effective factors and characteristics of different phase of drying process were obtained based on the analysis of the recorded experimental data. RESULTS: The influence of process parameters on evaporation rate varied in different period of drying process. CONCLUSION: In order to improve the efficiency of the integrated drying process,it's necessary to apply appropriate technical methods according to the characteristics of the process.