Passive aeration systems are more economical than active aeration systems and deliver similar performance, but mathematical descriptions of the process are inadequate for use in design or optimization. Therefore, a practical analytical model of airflow development in passively aerated compost was developed. The model relates the physical characteristics and temperature of the compost with the p...

‎the main purpose of this paper is to study the numerical solution of nonlinear volterra integral equations with constant delays, based on the multistep collocation method. these methods for approximating the solution in each subinterval are obtained by fixed number of previous steps and fixed number of collocation points in current and next subintervals. also, we analyze the convergence of the...

Oil pump in diesel engine has significant effect on energy consumption and environment pollution. In this paper, the modeling and simulation of a gear oil pump used in a diesel engine and its fluid flow analysis by a solver has been explained. Also the optimization and redesign of it has been discussed and then the outcomes have been compared with the experimental and previous results. The t...

Salmonella is the most commonly identified foodborne pathogen in produce, meat and poultry. Cattle are known reservoirs of Salmonella and the pathogen excreted in feces ends up in manure flush lagoons. Salmonella enterica survival was monitored in wastewater from on-site holding lagoons equipped or not with circulating aerators at two dairies. All strains had poor survival rates and none prolif...

The composition of the passive layers formed on Zn electrode in naturally aerated and de-aerated 0.1 M KClO4 solution were studied using X-ray hotoelectron spectroscopic measurements (XPS). A correlation between the presence of dissolved O2 and the formation of an interior passive ayer was carried out. Librated Cl− from the perchlorate reduction reaction was detected in its solutions during Zn ...

• Significant correlations between age group and performance for FRs (r=0.55, p<0.001) and PDDs (r=0.56, p<0.001). 2. Truth-Value Judgment Task Methods •Participants: 4yo (18), 5yo (17), 6yo (19), 7yo (11). •Participants were told: “Cookie Monster really likes cookies, but he does NOT like onions.” They were shown pictures of (i) plates of cookies, (ii) onions, or (iii) both cookies and onions....

in the traditional hole drilling method the in-plane stresses are studied in detail and the interlaminar stresses are not taken seriously. the interlaminar stresses on the free edge of composite materials are important and can cause matrix cracking and delamination. inserting holes in composite laminates causes free edges and it can induce interlaminar shear and normal stresses. in this researc...

Activated sludge systems are biological processes greatly used in wastewater treatment plants (WWTPs). These systems are composed of an aerated tank where the biochemical phase occurs and a settler where the physical phase takes place. Solid-liquid separation is one of the most critical steps in activated sludge processes. This stage presents three main objectives: sludge thickening, effluent c...