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Toner is a crucial dry colorant composite used in printing based on the electrophotographic process. The quality of printed images is greatly influenced by the toner production method and material formulation. Chemically in situ polymerization methods are currently preferred. This paper aims to optimize the characteristics of a composite produced through emulsion polymerization using common raw materials for electrophotographic toner production.

Emulsion polymerization provides the possibility to optimize the physical and color properties of the final products. Response surface methodology (RSM) was used to optimize variables affecting particle size (PS), PS distribution (PSD), glass transition temperature (T_g°C), color properties (ΔE) and monomer conversion. Box–Behnken experimental design with three levels of styrene and butyl acrylate monomer ratios, carbon black pigment and sodium dodecyl sulfate surfactant was used for RSM optimization. Additionally, thermogravimetric analysis and surface morphology of composite particles were examined.

The results indicated that colorants with small PS, narrow PSDs, spherical shape morphology, acceptable thermal and color properties and a high percentage of conversion could be easily prepared by optimization of material parameters in this method. The anticipated outcome of the present inquiry holds promise as a guiding beacon toward the realization of electrographic toner of superior quality and exceptional efficacy, a vital factor for streamlined mass production.

To the best of the authors’ knowledge, for the first time, material parameters were evaluated to determine their impact on the characteristics of emulsion polymerized toner composites.

The purpose of this paper is to conduct life-cycle cost analysis of a short-haul underground freight transportation (UFT) system for the Dallas Fort Worth international airport.

The research approach includes: identifying the cost components of the proposed airport UFT system; estimating life-cycle cost (LCC) of system components using various methods; determining life-cycle cash flows; evaluating the reliability of the results using sensitivity analysis; and assessing the validity of the results using analogues cases.

Although the capital cost of constructing an airport UFT system seems to be the largest cost of such innovative projects, annual costs for running the system are more significant, taking a life-cycle perspective. System administrative cost, tunnel operation and maintenance, and tunnel construction cost are the principle cost components of the UFT system representing approximately 46, 24 and 19 percent of the total LCC, respectively. The shipping cost is estimated to be $4.14 per ton-mile. Although this cost is more than the cost of transporting cargos by trucks, the implementation of UFT systems could be financially justified considering their numerous benefits.

This paper, for the first time, helps capital planners understand the LCC of an airport UFT system with no or limited past experience, and to consider such innovative solutions to address airport congestion issues.

This paper aims to study the natural convection of a nanofluid inside a cavity which contains obstacles using lattice Boltzmann method (LBM). The results have focused mainly on various parameters such as number and aspect ratio of roughness elements and different nanoparticle volume fraction. The isotherms and streamlines are presented to describe the hydrodynamics and thermal behaviors of the nanofluid flow throughout the enclosure.

The methodology of this paper consists of mathematical model, statement of the problem, nanofluid thermophysical properties, lattice Boltzmann method, LBM for fluid flow, LBM for heat transfer, numerical strategy, boundary conditions, Nusselt (Nu) number calculation, code validation and grid independence.

Natural convection heat transfers of a nanofluid inside cavities with and without rough elements have been studied. Lattice Boltzmann technique has been used as numerical approach. The results showed that at higher Rayleigh number (Ra = 10⁶), there are denser streamlines near the left (source) and right wall (sink) which results in better cooling and enhances convective heat rejection to the heat sink. After a distinctive aspect ratio of rough elements (A = 0.1), change in streamline pattern which arises from increasing of aspect ratio does not have an important effect on isotherms. Results indicate that for lower Rayleigh number (Ra = 10³), no variation in average Nu is observed with increasing in number of roughness, while for higher one (Ra = 10⁶) average Nu decreases from N = 0 (smooth cavity) up to N = 4 and then remains constant (N = 6).

Currently, no argumentative and comprehensive extraction can be concluded without fully understanding the role of different arrangement of roughness. Some geometrical parameters such as aspect ratio, number and position of rough elements have been considered. Also, the effect of nanoparticle concentration was studied at different Ra number. Briefly, using LBM, this paper aims to investigate the natural convection of a nanofluid flow on the thermal and hydrodynamics parameters in the presence of rough element with various arrangements.

Sequences of activities in people’s living environments have observable features that depend on subjective and meaningful aspects in their culture and lifestyle. Spatial and temporal sequences of activities are two ways of separating or aggregating activities. The theoretical framework of this study, based on cultural viewpoints, studies the activities, spatial and temporal distances and sequences of activities and their meanings in the dwelling environment. For the purposes of this study, a case study was done in the residential environment of the Qashqai tribe. For this study, a qualitative research method with data gathering techniques such as taking pictures from the environment and activities, drawing residential units’ maps, behaviour settings diagrams and semi-structured laddering interviews was used. Analytical findings were classified as either ‘spatial sequence’ or ‘temporal sequence’ of activities. The Means-End model, representing consequences and meanings of the sequences of activities, was presented in the form of ‘Feature-Consequence-Meaning’ diagrams. The results show that the sequences of activities in ‘Qashqai’ dwelling are influenced by such meanings as ‘social status’ and ‘family privacy’. Other consequences such as ‘desirable conditions of activities occurrence’ form conditions for lifestyle habitus in dwelling. In addition to providing a theoretical framework for the study of the human-environment relationship and the presentation of activity sequence properties, the results emphasize the meaningfulness of spatial and temporal sequences of activities in dwellings.

The aim of this paper is to apply a watery infrared filter for silicon solar cell efficiency enhancement in Kerman province of Iran as a talent region for solar energy production.

With this research, the water is applied as a filter for silicon solar cells in different volumes and thicknesses.

The obtained results showed that using various amounts of water could be a suitable choice for increasing the efficiency of silicon solar cells.

Other wavelength regions just cause the increase in the entropy and decrease in the efficiency. With this research, the water is applied as a filter for silicon solar cell in different volumes and thickness. The obtained results showed that using different thicknesses of water could be suitable choice for increasing the efficiency of silicon solar cell.

Few reports considering drug use among earthquake survivors exist. The present study aims to examine the Bam earthquake's impact on prescribing patterns and drug use among residents five years post‐disaster.

In this study, 297,104 prescriptions, issued by general practitioners in Bam city in 2008, were investigated for drugs/prescriptions, drug name, drug category, using WHO appropriate general practice prescribing indicators.

Mean drugs per prescription was 3.1. Drugs affecting the central nervous system were the most frequently used among Bam residents, representing 25.1 per cent, followed by antimicrobials, respiratory, cardiovascular and gastrointestinal tract drugs. Benzodiazepines were the most frequently used central nervous system drugs (15.8 per cent) followed by narcotic analgesics and tricyclic antidepressants. Penicillins (6.4 per cent) and cephalosporines (2.3 per cent) were the most frequently used antimicrobial drugs.

Results emphasize increased drug use for psychological disturbances and the need for strategies to improve mental health among disaster survivors.

Regarding the renewable energies, the cost of producing electricity and the remaining reserves from fossil fuels in Iran is compared with the same in other countries. Several advantages of renewable energies are studied in the present research with emphasis on solar energy; the Lut desert in Iran is introduced as a high potential for supplying the country’s energy. Various effects of such generation of energy on economy, environment, and public health are also studied.

Management writings in the Middle East region are scarce and scattered. This is due to the lack of doctorate programmes offered by educational institutions, the weak links between academia and the business world, limited formal and informal networks, the lack of status given to the field of management by national bodies and the lack of a publication culture. A bibliography of management‐related writings in the Middle East is presented, which includes other functional areas such as marketing, finance and accounting. It aims to draw the students' attention to a variety of sources. In compiling the bibliography a review of the literature in Arabic, English and Turkish was undertaken, followed by a survey of the top officials of academic institutions offering management/commerce, business administration degree programmes in the region.