Here the advantages of employing a biorefinery approach in conjunction with optimization techniques were utilized to attain high overall process efficiency. Initially, an alkaline pH-shift process assisted by ultrasonic and its subsequent optimization were employed to maximize the extraction yield and whiteness index of muscle proteins isolated from lanternfish (B. pterotum). The optimal strategy was determined as follows: 6 mL g-1, pH1 (solubilization) 11.5, 310 W, and pH2 (precipitation) 5.8 with desirability of 0.84. Collagen hydrolysate was obtained from the connective tissue-containing sediment residue emerging during pH-shift process. The optimal isolated protein (OIP) was utilized to produce heat-set gels in combination with collagen hydrolysate. Breaking force and deformation of the OIP gel were measured at 123 (g) and 10.12 (mm) respectively. Collagen hydrolysate made breaking force (up to 2% w/w) and deformation (up to 10% w/w) improved and had positive effects on color characteristics (especially whiteness index) as well as water holding capacity. Hence, it can be concluded that the integration of a novel extraction technique such as ultrasonic with pH-shift process followed by optimization, as well as concurrent utilization of muscle and connective tissue proteins through a biorefinery approach; provides a significant advancement towards scaling up the extraction process.

Today, microalgae are considered as an important source for the production of biofuels and pharmaceutical products. However, the lack of an efficient and economical method for dewatering and harvesting their biomass is is an important challenge to achieve this goal. The important issue for choosing the harvesting method are species characteristics, final product value and energy consumption. Therefore, in this study, the effect of flocculation method with pH change technique (range 6 to 11) using sodium hydroxide and hydrogen chloride on harvesting efficiency, and fatty acid content of Dunaliella salina was tested. The results of this study showed that with the addition of sodium hydroxide and increasing the pH from 8. 2 to 9. 8, the flocculation process increased upwards from 18 to 90% and then remained constant until: pH 11. In contrast, increasing hydrogen chloride and creating an acidic environment up to: pH equal to 6 had no effect on clot stimulation. The highest coefficient of biomass concentration was observed in alkaline treatment with pH: equivalent to 9. 8 which was 10 times the initial concentration (at pH equal to 8. 2 the effect of alkaline pH induction technique and the centrifuge technique on the fatty acids content of biomass was tested. In the next stage, the effect of alkaline pH induction technique and the centrifuge technique on the fatty acids content of biomass was tested. The analysis showed that the percentage of lipid and fatty acids of harvested biomass were significantly different from each other. Based on the obtained results, the flocculation method by increasing the pH by 9. 8 is a simple and relatively inexpensive technique with high efficiency and is suitable for harvesting Dunaliella salina microalgae for specific purposes.

The purpose of this work is to investigate the performance of nanofiltration membrane for separation of acid dyes. Nanomembranes have been developed by UV photografting technique. Acrylic acid was used for the modification of polysulfone ultrafiltration membrane that prepared via wet phase inversion method. The modified membrane characteristics were measured and the most suitable nanofiltration membrane was chosen for treatment of dye effluents. It was observed that selected UV-photografted membrane showed acceptable performance both in terms of flux and rejection. Acid dye retention was between 86 and 99.7% and hydraulic permeability was 7.6 L/m2 h bar. It was observed that increase of either dye molecular weight or dye charge leads to improve of dye separation that confirm the effectiveness of sieving and Donnan repulsion mechanism, respectively, in nanofiltration membranes. The influence of pH on the performance of membrane in terms of permeability and dye retention was established. It was found that by changing the pH (3, 6 and 9), membrane surface and dye have different behaviors that influence the final performance of selected nanomembrane. According to results, pH=9 of dye bath provides the best condition for dye separation.

This paper describes the details of synthesizing nano crystalline YBCO superconductor using a sol-gel combustion method and the effect of sol pH and sintering temperature on particle size was investigated. The sintering temperature was chosen 880oC and the samples were annealed at this temperature for 5 hours. The morphology and structure of the nano scale products were characterized by powder X-ray diffraction and scanning electron microscopy. The results showed the samples prepared using the sol with pH of 5 and 7 have mean particle size of 500 and 200 nm, respectively. In order to investigate the effect of sintering temperature on the size of YBCO particles three sets of samples from the sol with pH of 7 were sintered at 800, 880 and 950oC. The results showed the samples sintered at 800, 880 and 950°C have the average particle size of 100, 200 and 400 nm respectively.

In this research, the performance of three chemical compounds (Ferro sulfate, ferric chloride and calcium hypochlorite) and the effect of an increase of TDS on them in sulfide removal have been studied.The results showed that using these three chemical materials, chemical precipitation was a proper method for effluent treatment. With the change of pH from 4 to 9 under the concentration limit of sulfide 0.95-47.05 mg/l and following the study of 97 effluent samples, the highest sulfide removal efficiency of nearly 61.38-66.21% was observed in a pH of 7. Besides, after checking 59 effluent samples, Ferro sulfate with the concentration of 2-100 mg/l under the concentration limit of sulfide 0.95-47.05 mg/l had the highest sulfide removal efficiency of about 55.79-73.94%. Moreover, after studying 62 effluent samples, Ferric chloride with the concentration of 2-100 mg/l under the concentration limit of sulfide 0.95-47.05 mg/l had the sulfide removal efficiency of nearly 67.5-84.2%. Furthermore, Calcium hypochlorite with the concentration 10-500 mg/l under the concentration limit of sulfide (0.95-47.05 mg/l) and with checking 60 effluent samples had the sulfide removal efficiency of about 62.17-80.85%. It can be seen that the ratios of ferric, Ferro and hypochlorite ions to the sulfide ion are 2, 5 and 10, respectively and that Ferric chloride has the highest removal efficiency with less concentration. Finally, the results have shown that the decrease in the removal percentages of Ferro sulfate, Ferric chloride and Calcium hypochlorite by increasing TDS to 1000 mg/l was not significant while with the increase of TDS up to 1500 mg/l, sulfide removal efficiency is considerable.