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is one of the most common improved oil recovery method in the world. High residual oil saturation at the end of this method is due to low macroscopic sweep efficiency and viscous fingering. It can be improved by the mobility control during polymer solution injection. In this study, by of silica/ the effect of it on IFT, viscosity, and was investigated. In addition, the performance of in high salinity water was studied by using nano particles. The zeta potential results show that the stability of polymer solution was enhanced in of nano particles in high salinity water condition. Also, the lowest IFT was obtained for contained 1 percent nano silica (18.34 ), and the most tendency to water wet conditions was provided for this concentration. In addition to, 1 percent nano silica/ has the best performance on formation water viscosity and improved the mobility ratio to 1.07, which it can increase the oil recovery.

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Controlled delivery technology of protein/peptide drugs from biodegradable particles has emerged as one of the eminent areas to overcome problems related to macromolecules formulation. The goal of the present study was to develop protein-loaded micro-particles using biodegradable polymer, polycaprolactone (PCL) and hydrogel from beluga cartilage. Bovine serum albumin (BSA) was used as a model for protein/ peptide molecules such as GnRH. The double emulsion (W/O/W) technique was selected as one of the most appropriate methods for preparing a drug delivery system for soluble proteins in water. The first emulsion was prepared using ultrasonic and the mechanical agitator was used for achieving the second emulsion. The hydrogel prepared by enzymatic digestion was used in the first aquatic solution. At the present investigation, three groups were considered as the drug delivery system: G1; (PCL/hydrogel/BSA), G2; (PCL/BSA) and G3; (PCL/Alginate/BSA). Findings showed that the morphology of particles was spherical and non-conglomerated in all groups. The comparison of average particle size among groups was also indicated that the particles.

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Understanding the behavior of concrete at high strain rates loading is a critical issue for theory and applied purposes. The concrete is non-linear, rate-sensitive and pressure-dependent material that will add more difficulties in its modeling at high loading conditions such as impact penetration situations. In the present study, numerical simulation of penetration in a concrete target using an advanced plasticity concrete model is presented using explicit finite element (FE) analysis. A full 3D FE model of impact on unreinforced concrete specimens is carried out. The analysis includes initiation and progressive damage of the composite during impact and penetration Also comparison between some empirical solutions is carried out and their accuracy and precision are checked used experimental solution. Concrete nonlinear behavior was modeled using RHT model which is an advanced plasticity model for concrete at high strain rate loading condition. Two test examples are presented to demonstrate the proposed method. They involve the impact of an ogive-nose projectile on concrete cylinders with variable dimensions. The FEM computational results obtained using RHT plasticity model are very close to the test data, implying that the proposed method will be promising in studies of impact analyses of concrete structures subjected to impact loading. In using RHT model with the default model parameter values, the experimental results cannot be reproduced satisfactorily. Deduced results having good agreement withexperimental ones using suitable calibration of plasticity model parameters value. The RHT plasticity concrete model was developed as an enhancement to the JH concrete model by the introduction of several new features. In this new model, the strain hardening and the third invariant dependence were considered. An independent fracture strength surface was incorporated to allow for a more appropriate modeling of the material softening response. In addition, the concrete hydrostatic tensile strength was made rate dependent. Using a modified parameter setting, the RHT model implemented in AUTODYN hydrocode exhibits a generally excellent behavior. In this paper also, a comprehensive evaluation study of several widely used empirical penetration depth relation is presented. The model formulations are scrutinized and numerical tests are carried out to examine their actual performances subjected to various loading conditions. Comments on the limitations and the appropriate use of these models are given. In addition to penetration depth, damage extension, concrete sapling, scabbing and output velocity of missile and other time dependent structural quantities can captures well. This is in contract with imperial relations that have only penetration depth calculation capability for special conditions. On the other hand investigating of empirical relation shown in addition to their finite application ranges, they haven't good results in majority of cases. Among them, US army corps of engineers'' experimental based relation have better results compared other empirical relations for calculation of penetration depth.

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In the present study, a molecular based scheme has been developed for simulating of surface roughness and cavitation effects on nano- scale flows. In the nano-channel flows, there are some differences on the flow friction between roughness and cavitations which are not well studied. In the presented approach, based on the Molecular Dynamics Simulation (MD), the Lennard-Jones potential is used to modeling the interactions between particles. Each atom of the solid wall is anchored at its lattice site by a harmonic restoring force and its temperature has been controlled by utilizing thermostat.The roughness and cavitation have been implemented on the lower side of channel. To make a comparison between the effect of roughness and cavitation, the same dimension is used for both of them. Obtained results show, those hydrodynamic characteristics of flow and the walls shear stress depends on the roughness and cavitation sizes. The roughness on the bottom wall has more effect than cavity wall on the velocity and density profiles. Also results show that the presence of roughness on the bottom wall respectively increases the shear stress on the bottom wall and decreases its value on the top wall while, the presence of cavitation on the bottom wall has no effect on the top wall and just increase the bottom wall shear stress.

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In this paper, non-equilibrium molecular dynamic simulation has been employed to study the effect of wall interfacial properties and temperature of system on the hydrodynamics and heat transfer of water molecules in a nanochannel. The charges and Lennard-Jones potential are used to modeling the interactions between particles. The external forces are applied to the mass center of every water molecule in the x direction to create its flow and the thermal and hydrodynamics behavior of the water molecules was then analyzed. To construct the wall pore model, two silicon solid surfaces were used and the temperature of system has been controlled by utilizing Nose-Hoover thermostat. The interaction strength 〖(ε〗_(Si-W)) between wall atoms and water's oxegen atoms were adjusted to indicate different surface wettability or wall–fluid interaction. The higher value of 〖(ε〗_(Si-W)) , causes the higher hydrophilic wall interface. The simulation results showed that the interaction strength, (ε_(Si-W)) and temperature of system is important in determining the nanorheology of the nanochannel and flow resistance of the confined water. The drag resistance at the solid–fluid interface will increase with increasing the hydrophilicity of walls 〖(ε〗_(Si-W)). Also the heat dissipation of system will increase, with increasing the drag resistance at the solid–fluid interface, and it results, the heat flux of system will decrease.

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The experience of Northridge and Kobe earthquakes have demonstrated poor behavior of welded beam-column connections due to deficiency of welds. After numerous studies, proper method for welding of connection has been proposed. Yet, the proper procedure and detailing of welding usually do not follow due to insufficient supervision of welding process, therefore deficiency in the connection of a real steel structures is expected. One of the most common moment resisting connections in the steel structures is connection with top and bottom plates which is the subject of study in this paper. Among the possible deficiency in the welds, lack of penetration (LOP) and the lack of fusion (LOF) are two main deficiencies in these connections. In this study, the cyclic behavior of three steel moment resistant connection with LOP deficiency in the weld have been studied by analytical method. The deficiency was considered on the top, bottom and both top and bottom plates and results are compared with the original connection. The connections are selected from three different size (small, medium and large) to evaluate the size effect on the results. The connections are modeled by ABAQUS finite element software. The molding of the initiation and growing of cracks in the connections was conducted by the extended finite element technique (XFEM). In the beginning, to examine the efficiency and accuracy of modeling, an experimental study was used for verification. The hysteretic behavior of specimens was studied under the typical loading protocol of SAC and based on that, the constitutional behavior of connections was developed. The backbone curve of each connection was obtained and the curve of each deficiency was compared with each other and the original connection. Results show that in LOP deficiency, the crack is formed and grow in the welds which ultimately lead to rupture in the welds. In general, the deficiency reduces energy absorption, moment and ductility capacity of connections. The result in different beams size are very close which suggest that the size of the beam has not effect on the reduction of the capacity. To estimate the reduced capacity of connections with deficiency in the real cases, reduction coefficient is introduced and presented for yield and ultimate moment and yield and ultimate rotation. In general, it can be concluded that LOP cause 30% reduction in the yielding and ultimate moment capacity of connections and 20% reduction in the yielding and ultimate rotation of connection. In addition, to study the effect of different deficiencies on the reduction of absorbed energy, the area under the hysteresis curve are calculated and compared. The results indicated that the connection with LOP in both plate have the highest reduction in observed energy which follows by the LOP in top and then bottom plate. This results in addition to the value of reduction in capacity and ductility of connections indicated that LOP in the top plate cause the connection to fail in shorter cycles compare to other cases. Therefore, it is better to have not the LOP in top plate which needs special attention in welding of that plate which usually conducted in the workshop with the least possible of supervision.

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In this research, the effect of nanocomposite films based on PLA-PCL containing TiO₂ nanoparticles (3% by weight) and different levels of BEN (0, 1, 3 and 7% by weight based on polymer) on physicochemical and sensory properties of UF cheese during the 60-day storage at 4°C were determined.  The weight loss percentage, pH, acidity, hardness and peroxide value as well as sensory properties of the cheeses were examined. The results showed that during the storage period, the values of weight loss, acidity, hardness, peroxide value and microbial load of the cheese samples increased, and their pH decreased significantly (p<0.05), and the use of nanocomposite films based on PLA-PCL reinforced with TiO₂ and different levels of BEN could reduce the rate of changes in physicochemical parameters of UF cheese during the storage period compared to the control. A positive and direct relationship was observed between the BEN level and the antioxidant of the films in vitro conditions and in the food model. In terms of sensory properties, cheeses packed in films containing TiO₂ and different levels of BEN were acceptable until the last day of storage. According to the results obtained in this research, it can be concluded that it is possible to maintain the quality and safety and extend the shelf life of UF cheese by using nanocomposite films based on PLA-PCL reinforced with TiO₂ nanoparticles and BEN, and the best results are related to films containing 7% BEN.
 

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Dams are structures whose continuous evaluation is of great importance. Due to their large scale, experimental study of concrete dams is difficult and therefore, the numerical simulation is used in the dynamic analysis of such dams more effectively. Despite the widespread use of concrete, our knowledge on its exact properties and physical behavior under different conditions is still limited, and many assumptions and simplifications are made to study the concrete behavior in most studies. This is especially complicated in mass concrete structures such as concrete dams. The presence of joints in most concrete structures is common and inevitable. Lift joints in dams cause different characteristics in vertical and horizontal planes. In fact, this is a special type of anisotropy that follows axial symmetry with respect to any vertical axis, which means that the mechanical behavior is the same in all horizontal planes. The mechanical behavior in all vertical planes passing through the axis of symmetry is also the same, however, it is different from the behavior of horizontal planes. Since the lift joints are usually ignored in the numerical analyzes of concrete dams, in the present paper, taking into account the orthotropic behavior of concrete, the concreting joints that cause weakness in specific positions and directions of the dam body are included. First, non-linear seismic analyzes were performed using FEAP finite element software, then a Fortran program was coded to predict the time history of displacement. The proposed method draws upon evolutionary algorithms inspired by Darwinian biology, which are increasingly utilized as surrogate models for various analyses. This approach relies on data-driven learning, wherein algorithms, based on training or sample data, generate a mathematical model for making predictions.  The Pine Flat dam was modeled and analyzed under the Taft earthquake loading over a 20 second time interval with 0.02 second time steps. After successful training and learning, the model was compared and tested for other anisotropy ratios. The purpose of developing the program was to reduce the time required for analyzes so that by analyzing the initial seconds of seismic loading, by importing training inputs to the program, a proper prediction of the response process for the rest of the loading time could be obtained. In addition, by training the program for the isotropic and orthotropic modes, time history diagrams could be extracted for other orthotropic modes in different anisotropy ratios. According to the obtained results, the program is acceptably able to predict the graphs in a very short time. In addition, an equation for predicting the displacements in the orthotropic mode is presented. The maximum displacement of the orthotropic analysis was more than the isotropic one, and the use of isotropic material and homogeneous modeling of the dam body caused errors in the results. Therefore, considering the orthotropic properties of concrete can lead to more realistic results. The results reveal that time history plots derived from the implemented program closely resemble those from finite element analyses. The output results are remarkable, given the significantly reduced time required for predictions generated by the implemented program.

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