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While the fibers in concrete cause soft rupture, the compressive and tensile samples are not ruptured after failure. This is one of the benefits of metallic fibers, especially the sinusoidal and hooked fibers: using these gives residents the opportunity to escape during an earthquake. In addition to positively impacting mechanical properties, metal fibers improve the matrix of concrete, provide ductility and response to impact load, and control crack width and propagation. Fly ash and micro-silica improve the durability and performance of concrete and are effective in protecting the environment: they can, thus, be used to replace cement. In this study, the samples’ compressive and tensile strength was prepared: they were of non-fibrous concrete and concrete containing steel fibers with 6 different percentages (0.4, 0.6, 0.8, 1, 1.2, 1.5). They were also composed of metallic fiber and polypropylene in three different compositions (0.3PP + 0.8SF, 0.4PP + 0.4SF, and 0.15PP + 1.5SF). These were investigated: seismic parameters were extracted after achieving the optimal percentage (the percentage with the highest compressive and tensile strength given economic considerations) under the loading protocol SAC/BD 97.02. This allowed investigation of the curves of hysteresis, energy absorption, lateral displacement, and effects of the use of these fibers. The major properties of pozzolanic materials were considered in the last step of this research: fly ash and microsilica were added to concrete containing metal fibers with the optimum percentage of metallic fibers. These were compared with concrete containing metallic fibers and non-fiber concrete. Thereafter, the appropriate percentage of cement replacement was determined so as to better understand the effect of the use of fly ash and microsilica in preventing the buckling of buckling restrained braces.

Background and Objective: In recent years, management and disposal of municipal solid waste has become a global problem and the most important environmental concern. Anaerobic digestion is a cost-effective solution for treatment of both solid waste and wastewater. The aim of this study was to investigate the positive or negative effects of calcium chloride content in anaerobic digestion process of municipal solid waste and leachate on biogas production. Materials and Methods: Experiments with 8 levels of calcium chloride on co-digestion of municipal solid waste and leachate were investigated in 500 ml digesters under mesophilic conditions in a completely randomized design with three replications. Reactors with a ratio of substrate to inoculum of 2 (on VS basis) were operated and the volume of the biogas was measured daily. Volatile and total solids, carbon/nitrogen of waste, COD, BOD and heavy metals were measured by following APHA. Results: The results of the experiment showed that the pH was decreased with increasing calcium chloride concentration. The highest amount of cumulative biogas production was obtained in CaCl2 of 2 g/L with the highest VS and TS reduction. Higher concentrations of CaCl2 (≥3 g/L) caused a reduction in the degradability of volatile and total solids and, as a result, a decreased performance of the digester. Conclusion: The results clearly confirmed that the addition of calcium chloride was an effective solution to improve biodegradability in co-digestion of the MSW and leachate and consequently to reduce the total and volatile solids and to increase the amount of‌ biogas.

The main objective of this study is to design and construct the new, spouted bed dryer, for food drying sensitive foods specially. For this purpose, firstly a new design of dryer was planned to achieve the maximum efficiency and flexibility for liquids and solids drying. After constructing and initial setup of spouted bed, basic experiments such as investigation of an inert particles motion, pressure drop, energy consumption were conducted and optimal system requirements for two particle size (5.8 & 7.8 mm) were determined. The results indicated that changes in pressure drop in the dryer chamber containing inert particles are followed from the Ergun equation. Energy consumption in this system is variable in the range of 3-8 kW per hour. Also results reveals that the energy consumption of the new design of spouted bed dryer is less than the spray dryer for liquid foods drying.

According to the importance of expanding the use of clean energy, especially solar energy, in this study a solar cooker was designed, built and its performance in terms of the angle of the side mirrors at the same time and working time on the amount of energy absorbed was investigated by response surface methodology (RSM). The total amount of solar radiation as a measure of energy intake and increased water temperature inside the container was taken as an indicator of the amount of energy absorbed. The model on the basis of response surface methodology was used to validate the test and had a good validation (R2=0.89, R2adjusted=0.74 and lack of fit: no significant). Analyzing the results of a mathematical model was obtained for investigation of the effect of the side mirrors angle and time on the performance of the system. The amount of absorbed energy by theory and laboratory has been also compared and the average of error at all tests was 2.75%. Based on this model in the optimal condition, energy absorption was increased by 22.56%. This study was done at Institute of Food Science and Technology located in Mashhad with latitude 54 and 36 degrees and a height of 985 meters above sea level.

A lot of moment resisting steel frames were damaged, after Northridge earthquake. In these building, the usual rigid weld connection didn’t work properly and fielded. In the rigid weld connections, available Shear force in the flanges and lateral torsional buckling are the main reason for weld fracture.Slotted web connections, by improving many weaknesses present in moment connections were introduced by Seismic Structural Design Associates (SSDA), and has been classified as a special moment connection in the American Institute of Steel Construction (AISC), managed to qualify for the Federal Emergency Management Agency (FEMA) regulations.The Slotted Web connection design rationale that sizes the beam slot length, shear plate, and connection weldments, is based upon successful FEMA/AISC ATC-24 protocol test results and extensive inelastic finite element analyses of the beam and column stress and strain distributions. Incorporated in this rationale, which has been accepted by numerous departments of building and safety, are the UBC and AISC Load and Resistance Factor Design (LRFD) Specifications and the 1997 AISC Seismic Design Provisions for Steel Buildings and its supplements. In this connection, the separation of beam flanges removes the shear force from beam flange and it causes to transfer it on beam web. This connection is using moment resisting steel frame structure with proper behaviour and good seismic performance One of disadvantage of this connection is fast buckling of beam flange, to revise this problem in Slotted web connection we add a couple of vertical stiffness up and down the beam flange. Using of these stiffness, not only prevent fast buckling but also increase ductility and seismic performance and when we use these stiffness we will see, the absorbing of energy in hysteric loop will be more than the usual Slotted web connection.

Customer Relationship Management (CRM) is a productive tool for monitoring the customer and recognizing their characteristics, behaviors, and his/her requirements and anticipating his/her reactions in order to establish a long term and strong relation with customer. CRM is a business strategy selecting and managing the most valuable customer relationships. CRM includes different parts and dimensions that covers the whole stages of business from marketing to conclusion of contract, R&D, product/service design, sale and period after that. One of the important tools applied in CRM is Customer Lifetime Value (CLV). CLV allocates a quantitative value to each customer or a specific group and ranks them with this quantity. Different methods have been introduced to calculate this quantitative value. This paper tries to analyze all mentioned methods and presents the weakness and strength of each method. The most weakness of the typical method is not to concentrate on the future value of the customer. In order to rectify the weakness, in this paper an innovative model which combines two methods of RFM (which considers qualitative factors) and ROI (which considers financial factors) has been introduced. The validation of the model has been accomplished based upon real case study of one of the Iranian Insurance Companies.

For structural reliability assessment or risk analysis of aging offshore steel structures, it is essential to have a probabilistic model, which contains specific statistical parameters, and predicts long term corrosion loss as a function of time. The aim of this study is to propose such model for offshore jacket platforms in the Persian Gulf. Field measurements for material loss due to uniform corrosion for submerged members in seawater have been collected and statistically analyzed to identify the probability density distribution function for dispersion and variation of corrosion loss value according to the passage of time. To predict the corrosion loss, two probabilistic models with different approaches and time dependent parameters are suggested, based on the statistical analysis results. For a comparative study, the application of aforementioned models on the reliability analysis of a simple plate structure is investigated. Prediction results, obtained from the proposed probabilistic models, are consistent well with filed measurements.

In the present study, alkali roasting and oxalic acid leaching were used to extract titanium dioxide from ilmenite, and the effect of ethanol and ascorbic acid on the purity and recovery of titanium dioxide was investigated. In this research, ilmenite was alkali roasted with sodium carbonate for 4 hours at 900˚C. Then, the roasted ilmenite was leached with distilled water for 1 hour at room temperature. Finally, leaching with a mixture of 0.47M oxalic acid and different amounts of ascorbic acid and ethanol was performed at 65˚C. The results showed that using ethanol caused an increase in the amount of recovery and ascorbic acid increased the purity of the extracted titanium dioxide; also, the presence of these two factors at the same time simultaneously increased the amount of purity and recovery of the final product. Eventually, by choosing 0.47M oxalic acid, 0.005M ascorbic acid, and 48% ethanol as the appropriate conditions for leaching media and increasing the leaching time and temperature to 16 hours and 80˚C, it was possible to get titanium dioxide purities which were as high as 93.3% and 90.9%, respectively.

Background and Objectives: Cadmium can enter water resources through the industrial wastewater. It could cause intensivly damages to the liver and kidney of humans. Magnetic iron nanoparticles are used to control and eliminate heavy metals from industrial effluents through the mechanisms of adsorption, ion exchange and electrostatic forces. The aim of this study was to evaluate the efficiency of magnetic nanoparticles for adsorption of cadmium. Methods: The magnetite nanoparticles were prepared by co-precipitation method through the addition of bivalent and trivalent iron chloride under alkaline conditions. Characteristics of nanoparticles including particles structure, composition and size were determined using analytical devices such as XRD, SEM, and FT-IR. For optimization of adsorption process of cadmium, some parameters such as pH, contact time, initial concentration of cadmium, nanoparticles concentration, and temperature were studied under different conditions. Results: It was found that 95% of cadmium could be removedAt pH ≥ 5.6, 10 mg/L initial cadmium concentration, a dose of 1 mg synthesized magnetite nanoparticles, 10 minutes contact time, and 200 rpm mixing rate at 25 °C. The isotherm of adsorption follows the Langmuir model (R2 < 0.995). Maximum capacity of cadmium adsorption was found to be 20.41 mg/g. Conclusion: Magnetite nanoparticles exhibit high capability for removal of cadmium. The nanoparticles synthesized could be used at industrial scale because of having the magnetic property, which make them easily recovered from aqueous solution through applying a magnetic field.

Introduction: Organization culture explains the characteristic of any organization. Organization culture includes values, standards and portrays behavior of members of that organization. Considering the pivotal role which is played by human resources and also the cost borne by these human sources, any kind of neglection on part of management can be drastic. Methods: This cross-sectional study included 95 employees of Yazd health care institutions. Data collection was through a questionnaire based on 10 dimensions and 44 indicators about organizational culture in EFQM environment. Results: The situation regarding organizational culture dimensions was not appropriate from viewpoint of EFQM in any of the health care institutions. Conclusions: Spurred by impressive results in other industries, this compelling and logical approach has begun to penetrate the thinking of health care accrediting agencies, business coalitions, private foundations and leading health care organizations. In this case, making some potential situations and using the study results of improvement of organizational culture can develop environmental situations for employee’s promotion and firm growth.