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Spinel ferrites are attaining huge importance in the modern era, due to their incredible properties, which means they are widely used in various fields. Therefore, in this paper a cost-effective and environmentally friendly preparation of Mg0.25Ni0.25Cu0.5−xCoxFe1.97La0.03O4 (x = 0.0, 0.125, 0.25, 0.375, and 0.5) ferrites via the sol–gel auto-combustion method were carried out. How the structural and functional properties varied with the Cu to Co ratio was studied. It was found that the crystallite size (D) was reduced from 47.2 to 27.6 nm as the Co2+ increased from x = 0.0 to 0.5. While the two major absorption bands including the higher frequency band (υ1) and lower frequency band (υ2) lie in the range of 573.80–538.65 cm−1 and 470.37–405.65 cm−1 belong to the spinel matrix. Five active Raman modes were found in the range of wave number 200–800 cm−1 corresponds to the sublattices of the spinel structure. The optical bandgap increased from 0.85 eV to 1.33 eV for x = 0.0 to x = 0.25 and then observed optical band gap was 1.15 eV and 1.46 eV for x = 0.375 to x = 0.5. The resistivity (ρ) was minimum for Co2+ concentration x = 0.25 at low temperature, while at high temperature the resistivity (ρ) was maximum for Co2+ doping x = 0.25. The temperature coefficient of resistance percentage (TCR %) was −2.66%/K at 513 K for x = 0.25, as shown in the graphical abstract. At lower frequencies, the impedance was observed maximum for Co2+ doping x = 0.125 and minimum for x = 0.375. These findings indicate that the as-prepared ferrites are a potential candidate for optoelectrical and bolometric devices. Highlights: Mg0.25Ni0.25Cu0.5−xCoxFe1.97La0.03O4 synthesis via the sol-gel auto-combustion method. The crystallite size was decreased with Co2+ doping. At high temperatures, the resistivity (ρ) was maximum for Co2+ doping x = 0.25. At lower frequency, the impedance was maximum for Co2+ doping x = 0.125. The temperature coefficient of resistance percentage (TCR%) was −2.66%/K at 513 K for x = 0.25. [ABSTRACT FROM AUTHOR]

This comparative study investigated the microstructural, thermophysical, and mechanical properties of tea waste–, sawdust-, and wheat husk–incorporated clay bricks. The bricks were prepared by missing clay with different amounts of organic wastes and firing at 600°C and 1,000°C. A transient plane source technique was used to measure the thermal properties of the fired bricks. The calorific values of the tested organic wastes were measured in the range of 15–17 MJ/kg. The maximum loss on ignition of tea waste–, sawdust-, and wheat husk–incorporated bricks was measured at about 14.94%, 13.75%, and 9.26%, respectively. The tea waste added–bricks exhibited the highest water absorbance, 20.8%–35.7% , among all the tested samples. The specific surface area of the tea waste–, sawdust-, and wheat husk–added bricks was measured at about 146.43, 139.47, and 167.25 m2/g , respectively. Similarly, the pore volume was measured at about 0.192, 0.184, and 0.219 cm3/g , respectively. When compared with a reference brick, the compressive strength decreased by 15%–59% for 2%–8% by weight of tea waste, by 12%–59% for 2%–10% by weight of sawdust, and 31%–69% for 1%–4% by weight of wheat husk in the brick. However, the compressive strength of the waste-added bricks was still in good agreement with Pakistan building code standards. [ABSTRACT FROM AUTHOR]

This article is based on a study, conducted in 2012, to analyze the effect of CPD Framework on teachers' moral development. Directorate of Staff Development (DSD) Lahore launched the 1st Phase of CPD Framework in 2007 for 12 districts of Punjab, Pakistan. The major objectives of the study were (1) to analyze the opinion of head teachers, peer teachers, and students about teachers' moral development as a result of the CPD Framework; (2) to evaluate the differences between teachers of urban and rural areas after participating in the CPD Framework; and (3) to analyze the differences among the districts regarding teachers' moral development. Data were collected from head teachers, peer teachers and students of 344 government boys' primary schools of four selected districts. CRD design and LSD test were used to analyze the data. From the findings of the study it was concluded that the effect of CPD Framework was higher on teachers of urban areas than the teachers of rural areas, the students were more satisfied with their teachers' moral development than the peer teachers and the head teachers, and effect upon the districts was also found varied but it was highly positive. It was recommended that the CPD Framework must be monitored regularly especially in rural areas to minimize the differences between urban and rural locality. [ABSTRACT FROM AUTHOR]