Oxychlorination of various phenols is finished in 60 minutes with high efficiency and perfect selectivity under microwave irradiation. These reactions adopt copper(II) chloride (CuCl2) as the catalyst and hydrochloric acid as chlorine source instead of expensive and toxic ones. Oxychlorination of phenols substituted with electron donating groups (methyl, methoxyl, isopropyl, etc.) atortho-andmeta-positions is accomplished with higher conversion rates, lower reaction time, and excellent selectivity. A proposed reaction mechanism is deduced; one electron transfers from CuCl2to phenol followed by the formation of tautomeric radical that can be rapidly captured by chlorine atom and converts intopara-substituted product.
Soil-rock mixture is a commonly used geotechnical material used in many construction projects, such as slopes, tunnels, and dams. The shear strength of soil-rock mixture is its key property and is affected by many factors. This study aimed to investigate the shear strength characteristics of soil-rock mixture and the influences of moisture and stone content on shear strength parameters. Soil-rock mixture samples with four different stone and moisture contents were fabricated and tested using a large-scale direct shear test apparatus under four vertical pressures. The results demonstrated that the shear properties of the soil-rock mixture showed significant Mohr Coulomb failure criteria for all stone contents. As the moisture content increased, the shear strength of the soil-rock mixture first increased by 10~18% and then decreased after w = 12% to the residue value. The change in cohesion and internal friction angle of soil-rock mixture with different moisture contents shared a similar trend. For w < 12%, the cohesion and internal friction angle increased with moisture content, and for w > 12%, the two indexes obviously decreased. As the stone content increased from 30% to 60%, the shear strength of the soil-rock mixture increased by 82~174%. The internal friction angle increased linearly with stone content, while the cohesion of the mixture first increased and then decreased after the stone content reached 50%. The results can help in the designation and application of soil-rock mixture.
A variety of thinking skills interventions have been implemented in schools and relative assessments emerged. However, due to inconsistencies of assessment techniques and lack of norms from large-scale samples, it remains problematic to compare the effects of various thinking interventions in general. This study aimed to investigate the current situation of thinking skills of 2096 pupils in 4 th , 5 th , and 6 th grade from six primary schools located in Beijing, Guangzhou, and Xi'an respectively. The "Assessment of Pupils' Thinking Skills (APTS)" measure developed by Burke and Williams (2012) was translated into Chinese and used as the instrument. Results demonstrated that there were significant improvements in the pupils' overall thinking skills from 4 th to 5 th grade and from 5 th to 6 th grade as well. However, the pupils' metacognitive reflection did not improve significantly from 4 th grade to 5 th grade while they increased dramatically from 5 th to 6 th grade. The pupils' definition of thinking skills and application of some thinking skills (i.e., Grouping, Finding Reasons and Conclusions, Decision Making and Problem Solving) showed the same trends as metacognitive reflection. Differentiations in thinking skills development were found when compared among schools. Reasons for these differentiations and implications for teaching thinking in primary schools were discussed.
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