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The porosity of electrospun nanofibers web is a significant parameter affecting various areas of nanofibers applications. Thus, at first, the effect of most effective parameters, the concentration of polymer solution and flow rate, on the diameter of polyvinyl alcohol nanofibers, as a dissolving component, were investigated. Afterward, the hybrid web of polyamide 6/polyvinyl alcohol (PA/P) was prepared via a two-sided dual-nozzles electrospinning method. The morphology, diameter, pore size of nanofibers web and the effect of dissolving constituent were studied based on images of the scanning electron microscope. To measuring the porosity of nanofibrous webs, three practical and straightforward methods that have been proposed in the literature were utilized. It was observed that when one component was dissolved, the diameter of the resultant web was decreased, and the porosity has been reduced to about 70% based on the best selected method of porosity. Additionally, the average pore size of electrospun PA6 webs has been decreased about 30-58% relative to the original hybrid webs.

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Aims: The arrival of European architects and the return of the Iranians students were the root of modern architecture in Iran. Roofing with truss structures is one of the architectural achievements of this period. In many buildings, and even for covering industrial buildings, trusses were used to cover large spans. The present study tries to address the differences between Iranian and non-Iranian truss structures in industrial heritage buildings.

Methods: The first step of the research is documentation. The second part is based on the field study and structural analysis. Six samples were selected from among from the shared-heritage of Iran and Germany in the late Qajar and beginning Pahlavi era in the Gilan and the Mazandaran provinces. The methodology was set to explain the difference between Iranian and non-Iranian truss structures.

Findings: Among the six selected samples of sloping structures, the two were made with Iranian truss systems and in the four other samples non-Iranian truss systems. The first group is only pretending to be sloping structures but the second group could be categorized as real truss structures.

Conclusion: Investigating the two different groups of sloped roof structures suggests that Iranian truss systems are different from the western truss due to deployment of elements, cut of the wood, joints and distribution of forces. It shows that what we name as Iranian systems of truss structure is only similar in face with the western truss systems; and in statics point of view, those are different obviously.

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Aims: This study aimed to determine the correlation between health-promoting hospitals’ standards and nurses’ caring behaviors.
Instrument & Methods: This correlational study was conducted on 228 nurses working in hospitals affiliated with Birjand University of Medical Sciences in 2021 in Birjand, Iran. The research instruments included the demographic characteristics checklist, the Caring Behavior Inventory, and the World Health Organization’s Health Promotion Standards Adherence Scale.
Findings: There was a significant positive correlation between the total score of health-promoting hospital standards and the total score of nurses’ caring behaviors from the perspective of nurses (p<0.001, r=0.494). Likewise, there was a significant positive correlation between all dimensions of health-promoting hospitals’ standards and all dimensions of nurses’ caring behaviors (p<0.001).
Conclusion: Hospitals enhance nurses’ caring behavior by following health-promoting hospital standards and fostering a positive work environment with improved inter-professional relationships.

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Objectives: The main goal of the research is to introduce tea factories and to recognize their architectural patterns, which are considered to be an exclusive example of industrial architecture in northern Iran. Therefore, the research takes into account 6 components and analyzes 4 selected examples of factories, and separates the architectural pattern of each one.
Methods: This research is based on quantitative-qualitative method, relying on descriptive-analytical strategies and studying the architectural features of tea factories built in Northern Iran, during the Pahlavi period. Historical studies have been done by referring to historical documents or referring to the archives of Iran Tea Organization and Tea Research Institute.
Findings: The analysis of the architecture of tea factories based on 6 components shows the plan, volume, roof structure and type of covering, materials, facade, openings and decorations.  In the 4 examples of tea factories, two are the first Pahlavi examples built by European architects, and in the other two examples from the second Pahlavi period, a combination of modern and traditional architecture is evident in the body of the buildings.
Conclusion: The predominant pattern of tea factories in Iran is an axial plan with a central projection, a sloping roof, row openings and a simple view. It was first performed by German architects in Iran. In the examples of the second side, with the presence of traditional architects and the use of materials such as bricks, the facade was reduced.

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The present study probes the nonlinear free vibrations of viscoelastic polymeric composite plate reinforced by carbon nanotubes. For this purpose, Kelvin-Voigt model is utilized. Moreover, the equations of motion are extracted by the Hamilton principle and taking into account Von Karman nonlinearity. In order to solve and analyze nonlinear free vibrations, the researchers utilized multiple scales method. Thanks to this method, the normal nonlinear frequencies of the system were obtained, and as well, the impact of various factors such as dampness coefficient, material viscosity and carbon nanotubes volume fraction were investigated. Besides, the thickness-dimension ratio of the plate and its impact on the normal frequency was also studied. The findings of the study highlighted that an increase in the ratio of plate’s thickness to its length causes an increase in the normal nonlinear frequency of the plate. Additionally, as the volume fraction of the carbon nanotubes increases, system’s normal nonlinear frequency increases as well. Finally, the impact of different distribution of carbon nanotubes on the normal nonlinear frequency and system’s time response was also probed. As it could be vividly observed, nonlinear frequency for FGO distribution was reported to be further than uniform distribution, but the trend was in reverse for FGX distribution.

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In this study, the drying process of pumpkin thin layers was investigated by cast tape drying (CTD) and convective hot air drying (CHD) methods and the effect of temperature and drying kinetics of the pumpkin was determined along with  the best mathematical model to fit the changes on moisture content to time ratio. At first, Pumpkin slices were prepared with 3, 5 and 7 mm thicknesses. Drying was performed at 75, 85 and 95 (°C) by CTD method and at 55, 65 and 75(°C) by CHT method in triplicate. Based on the kinetic model evaluated by Hii, Law and Cloke, the 7 mm thickness was selected as an optimum thickness in both drying methods. The optimal drying temperature ranges were 55 and 95 (°C) by CHD method and CTD method, respectively. Five mathematical kinetic models were fitted on the experimental data using four criteria including, Determination of Coefficient (R²), Root Mean Square Error (RMSE), Sum of Squares (SSE) and Chi-square (χ²). Also, effective diffusion coefficient (D) and activation energy (Ea) were calculated. The results showed that Hii, Law and Cloke’s model predicted the drying behavior during CTD. Activation energy of 37.5310588kJ/mol and 20.32657 kJ/mol was calculated for CHD and CTD methods respectively. The best mathematical model for drying a thin layer of pumpkin by CTD and CHD method was proposed Hii, Law and Cloke’s model.