The focus of the research was to find science teachers' philosophy about the nature of science NOS in philosophical perspectives serving in the public sector universities of Pakistan. The descriptive research method was used to investigate the difference in perceptions of the science teachers about NOS on the basis of gender and subject. An online questionnaire was utilized in order to gather data from respondents. Different constructs of NOS were identified to explore. The female teachers had more understandings about NOS than male teachers. The teachers of mathematics were positivists and decontextualized view of NOS. Male teachers were having an inductivist view of NOS. Physics teachers believed in inductivism. The teachers of chemistry were having process and realism view of NOS. Mathematics teachers were found to have contextualized NOS. It is recommended to provide orientation to science teachers in order to build NOS towards concept clarification during the process of the teaching-learning process.

The present study was conducted in order to investigate the efficiency of different advanced oxidation processes both individually and in combination with the biological method for the removal of color and chemical oxygen demand (COD) from wastewater in the pulp and paper industry. Advanced oxidation processes include ozone, Fenton, hydrogen peroxide, and photo-Fenton. Biologically treated wastewater was successively subjected to advanced oxidation processes (AOPs). The optimum conditions for the ozone treatment of raw wastewater were found to be a contact time of 9 min and a pH of 5 at a fixed dose of ozone for a removal efficiency of 41.22% for color and 88.53% for COD. Similar optimum conditions for the ozone treatment of biologically treated wastewater showed a removal efficiency of 46.36% for color and 95.92% for COD. The photo-Fenton process also showed an efficiency comparable to the ozone treatment for both raw wastewater and biologically treated wastewater, resulting in a removal efficiency of 39.85% (color) and 90.13% (COD) for raw wastewater, and of 41.34% (color) and 94.29% (COD) for biologically treated wastewater. Each had a contact time of 12 h. The Fenton oxidation of raw wastewater showed a removal efficiency of more than 26.30% for color and 86.33% for COD. Fenton oxidation, however, showed an efficiency of 26.62% for color and 84.49% for COD removal from biologically treated wastewater. Hydrogen peroxide showed an efficiency of 28.45% for color and 85.13% for COD removal from raw wastewater, and 39.48% for color and 86.53% for COD removal from biologically treated wastewater. The results for the raw wastewater treatments indicated that higher removal efficiencies can be achieved when they are used as pre-treatments. Biological treatment is a cost-effective method but it has less efficiency for color removal. In combination with one of the AOPs, either as a pre- or post-treatment under a controlled time and dose, biological treatment increased the efficiency, making treatment feasible at larger scales.

Scientific attitude towards science education facilitates twenty first century learning and provides a strong foundation for learners academic achievement. Science education at secondary level is placed as a backbone towards higher secondary level. The focus of the present study was to investigate the instructors and learners scientific attitudes towards physics at secondary level. Quantitative data were collected through questionnaires by using survey research from 1000 random sampled respondents i.e. instructors and learners. Multistage stratified sampling technique was applied in the present research and the collected data were analyzed through descriptive and inferential statistics. A low level of learners attitude towards physics was found which reflects in learners academic achievement level in physics. Scientific approach among learners can be promoted through instructors attitudes towards physics at the secondary level, which will be beneficial for the development of Pakistan.