m. salimi

Polyolefins, including polyethylene and polypropylene, represent one of the most important families of plastic materials, indispensable in modern life. Achieving optimal properties for these materials is essential, and this depends heavily on advancements in catalyst support and polymerization technology. The production of high-performance catalysts plays a crucial role in improving polymer properties. Recent research has focused on using metal chlorides (Lewis acids) in Ziegler-Natta catalysts to enhance catalytic activity and polymer characteristics. This study introduces a novel precipitation method to prepare the MgCl2-based support and investigates the modification of the TiCl4/MgCl2/EtOH/Surfactant catalyst system with AlCl3, ZnCl2 and their combination. The results demonstrate that the combined use of AlCl3 and ZnCl2 significantly outperforms the individual modifiers, with the optimal   ratio of 14 yielding the highest activity (24-26 kg PE/g cat.). Differential scanning calorimetry (DSC) analysis revealed that the thermal properties, including melting temperature (135.7 ℃) and crystallinity (56.5%), remain largely unaffected by the modification. Additionally, gel permeation chromatography (GPC) results showed a significant increase in molecular weight (42 × 104 g/mol) and polydispersity index (22.1). The modifications improved comonomer incorporation and enhanced key polymer properties, such as molecular weight distribution and bulk density, while maintaining comparable morphology to the unmodified system. These findings highlight the potential of tailored catalyst modifications for advancing polyolefin production.

Improving the deviant behavior of employees in organizations has always been of interest. The aim of the current research is to investigate the role of spiritual health and monetary ethics in dealing with the deviant behavior of employees of sports organizations with regard to the mediating role of work ethics.

The research is applied in terms of purpose and descriptive in nature. The statistical population of the research was formed by managers and experts of sports and youth departments of Isfahan province in 1401, out of 1430 people, 750 people using stratified sampling method according to the volume, selection and data using questionnaire. were collected by researchers. Content and construct validity were used to measure validity, and Cronbach's alpha coefficient was used to measure reliability. Confirmatory factor analysis was done in SPSS and the model was confirmed in AMOS.

There is a significant relationship between spiritual health and monetary ethics. A significant relationship can be seen between spiritual health and work ethics. This connection between monetary ethics and work ethics is also observed. Spiritual health, money ethics, and work ethics each have a significant relationship with deviant behavior. Work ethic acts as a mediator between spiritual health and deviant behavior, as well as monetary ethics and deviant behavior.

In order to manage the deviant behavior of employees in sports organizations, it is necessary to pay attention to the variables of spiritual health, money ethics and work ethics and provide the ground for improvement in these organizations.

The current study investigates the two-phase turbulentnanofluid flow insidein a heat exchanger tube equipped with a novel type of conical turbulators having two parallel rows of holes, for first time.The range of Reynolds number was between 4000and20000 under turbulent flow regime and uniform wall temperature condition.Water is considered as the base fluid and TiO2 nanoparticles with volume fractions of0–2.5% are added as the second phase to the base fluid.The effect of number of the conical insert turbulators, number of the holes and volume fraction of the nanoparticles on flow field,average Nusselt number,friction factor and performance evaluation criterion(PEC) have been numerically investigated.The results show that the proposed turbulators create vortices and recirculating currents that have significant effect on heat transfer.As number ofthe turbulators increases,Nusselt number increases obviously.However,the presence of holes also reduces the friction factor andpressure drop that is related to lower resistance in the flow path.In general,the use of perforated conical turbulators improves PEC by creating controlled turbulent flows.Onthe otherhand,the useof added nanoparticles also enhances heat transfer.The presented turbulators increase PEC up to43% compared to the smooth tube,if the parameters are determined properly.The maximum PEC of1.43 is obtained at M=8,N=4 and Re=4100,which shows good performance compared to othertypes of turbulators.

The separation of carbon dioxide is essential for the environment. Using membranes to separate this gas is economical, but the weakness in permeability and mechanical strength has prevented their commercialization. Robeson proved that permeability and selectivity have the opposite relationship and provided an upper limit for pairs of gases. Worth to be mentioned that any membrane placed above this limit could be commercialized. Scientists proposed mixed matrix membranes to overcome this problem. These membranes contain two phases, polymer, and inorganic. This research focuused on membrane technology and aimed to prepare a membrane that has a good performance for CO2 separation and at the same time its cost is economical, so by adding a reasonable price zeolite available in the market named 4A to the Pebax1657 polymer and changing the operating conditions of the process, permeability and Selectivity was measured. Pebax polymer and 4A zeolite were selected as respectively the polymer and mineral phases for membrane fabrication. The fabricated membranes were evaluated by XRD, FT-IR, FE-SEM, BET, EDAX, TGA/DSC, and mechanical strength tests. Finally, the selectivity of CO2 compared to N2, O2, and CH4 improved by 53, 67, and 75%, respectively, and obtained a good position on the Robeson diagram.

The main goal of this research is the modeling and optimization of the ethylene oxychlorination reactor in the Arvand Petrochemical Complex. In this process, the dichloroethane is produced through the oxychlorination of ethylene on CuCl3 supported Al2O3 catalyst. The ethylene oxychlorination reaction occurs in a fluidized bed reactor equipped with a heat exchanger to control operating temperature. In the industrial plant, the oxychlorination and direct chlorination processes are in parallel and produced HCl in the direct chlorination and EDC cracking units fed to the oxychlorination reactor. In this research, the oxychlorination reactor is modeled based on the mass and energy balance equations at steady-state conditions. Due to fluid specifications and flow regime, a two-phase flow regime including bubble and emulsion phases with mass transfer between phases is selected to simulate the reactor. To prove the accuracy and precision of the considered model and assumptions, the simulation results are compared with the plant data. Then, an optimization problem is programmed to maximize the dichloroethane production rate based on the design and operating limitations considering feed temperature, coil temperature, operating pressure, and mass flow rate of hydrogen chloride and oxygen as decision variables. The simulation results show that applying the optimal operating condition on the system increases dichloroethane production from 128.7 to 141.3 mol/s.

Considering the presence of different model parameters and controlling variables, as well as the nonlinear nature of DC to AC inverters; stabilizing the closed-loop system for grid current balancing is a challenging task. To cope with these issues, a novel sliding mode controller is proposed for the current balancing of local loads using grid-connected inverters in this paper. The closed-loop system includes two different controlling loops: a current controller which regulates the output current of grid-connected inverter and a voltage controller which is responsible for DC link voltage regulation. The main features of the proposed nonlinear controller are reactive power compensation, harmonic filtering and three-phase balancing of local nonlinear loads.  The developed controller is designed based on the state-space averaged modelling its stability and robustness are proved analytically using the Lyapunov stability theorem. The accuracy and effectiveness of proposed controlled approach are investigated through the PC-based simulations in MATLAB/Simulink.

Organizational hypocrisy is considered as one of the sources of corruption and also as one of its consequences that overshadows all aspects of the organization. When the complication of hypocrisy arises at the high and strategic level of the organization and is linked to organizational policies, it creates greater and more serious risks and problems. The aim of this study was to design a model for measuring the hypocrisy of organizational policymakers in government organizations. 

This research is among the qualitative and exploratory researches that were done using the data method of Grounded theory. The statistical population of the study was experts (managers of government organizations in Lorestan province) and 24 of them were selected as a sample by snowball method. The research tool was a semi-structured interview that was finally analyzed using open, axial and selective coding methods.

In the open coding section, 176 codes were extracted. In the axial coding section, 62 codes were placed in the form of 12 selected codes, thus forming a conceptual model of the research.   

According to the research results, the causal factors identified in the field of policymakers 'hypocrisy include two spectrums of individual and organizational factors, and the employment conditions that create hypocrisy and the conditions that create hypocrisy are among the underlying factors of policymakers' hypocrisy. On the other hand, the central phenomena in the present study were identified in the form of two axes of organizational hypocrisy and hypocritical behaviors. Hypocrisy coping strategies and the consequences of organizational hypocrisy are also other components of the model.

The rapid spread of COVID-19 has recently become a worldwide health challenge. Coping with the highly contagious outbreak of COVID-19 requires preventive measures and self-care behaviors in the first instance. To this end, the use of techniques and methods of coping, disease prevention as well as management, lifestyle, education and use of health items and providing self-care instructions can prevent further spread of the disease. The aim of this study was to determine the prioritization of self-care indicators in the prevention of Covid-19 in Ardabil province, which is one of the foci of this disease.

This descriptive-field survey was conducted from the beginning of Covid-19 outbreak (March 1998 to January 1999). The sample size consisted of 120 people who were selected using the available snowball sampling method. Data analysis was performed using TOPSIS analysis software and formulation in Excel software based on weighting with entropy algorithm and prioritization with TOPSIS algorithm.

The results of this study showed the Sub-indics of increasing awareness of people about the prevalence of infection with proximity with coefficient (CLi +) of 0.8673, washing hands with soap and water or disinfecting with alcohol-based solution with proximity coefficient (CLi +) of 0.9391, electronicization of most activities Employees' work with a coefficient of closeness (CLi +) of 0.8687, observing a safe distance (1.5 meters) from people who cough and sneeze with a coefficient of closeness (CLi +) of 0.8277, avoiding any gatherings with a coefficient of closeness (CLi +) 0.9276, as the most important indicators among self-care methods in Ardabil province.

This study was a proposed method to assist health care providers in making decisions and selecting the COVID-19 self-care model in Ardabil province

α-Fe2O3 is a stable, cheap, and non-toxic metal oxide with many advantages and different fields of application. Many attempts have been devoted to the synthesis of α-Fe2O3 with different crystal structures and morphologies to obtain the desired properties. In this research, nanostructured α-Fe2O3 were synthesized by a facile solvothermal route. The as-obtained samples are characterized by XRD, FESEM, EDS, FTIR, and BET surface area analysis. The results showed that the as-synthesized hematite consists of nanostructures with the morphology of distorted microspheres with an average diameter in the range of 1 to 1.5 µm each composed of self-assembled nanoparticles with an average size in the range of 10 to 30 nm. The results showed that the hematite nanostructures had a specific surface area of 41.86 m2g-1. The influence of temperature and duration of the solvothermal process as well as, calcination on the structural properties of the α-Fe2O3 samples was investigated. The results reveal that the crystallite size of the samples increases with increasing the temperature and duration of solvothermal treatment. Moreover, calcination leads to an increase in the crystallite size of the samples. The α-Fe2O3 nanostructures with a minimum crystallite size of 13.6 nm were synthesized at 150 °C for 4 h while the largest crystallite size of 75.4 nm was obtained at 180 °C and 8 h with subsequent calcination of the sample at 500 °C for 1 h. The results of the present study can be useful to enhance the properties of α-Fe2O3 nanostructures in various fields of application.

Aspromazine has a sedative effect in animals and is used without any significant effects on domestic animals. Aspromazine in the wildlife has been recommended for reptiles, amphibians and small mammals but is contraindicated for gerbils. The aim of this article was to investigate the possible cause of death in wild gout. Wild gout, about 5 years old, without complying with species-specific transportation standards was transferred to Khorramabad quarantine post (Kaldar-Sefid kooh) without any history of illness. At first the animal has severe symptoms of restlessness, increased number and depth of breathing. In order to sedate the animal 2 mg Aspromazine was administered. After about 15 minutes the animal was died. At the necropsy, complications of trauma in the jaw and eye area, edema and congestion in lung, congestion and hemorrhage in trachea, endocardial hemorrhage, and meningeal hemorrhage were observed. Histopathological evaluations show hyperemia and severe pulmonary hemorrhage, severe infiltration of mononuclear inflammatory cells with mild fibrin leakage in the alveoli. However, the inadequate time from the onset of the disease process to the death has restricted the full incidence of lesions; it seems that the cause of death is hyper acute or capture shock syndrome.

In this paper, a novel approach for regulation of the output current in the grid-connected three-level flying capacitor inverter is presented by using the sliding mode (SM) method. In the proposed method, it is possible to control the active and reactive components of the inverter output current independently, and therefore it can be employed for grid connection of the renewable energy resources or for harmonic and reactive power compensation of the local loads. The designed controller uses an external loop to control the voltage of the inverter DC link and has a constant switching frequency. The stability of the proposed method has also been proved by using the Lyapunov stability theory. The simulation results show that in different operating conditions, the proposed controller has a stable and robust response.

Grid-connected three-level flying capacitor inverter is modeled by using averaged state space technique. Considering nonlinearity of the obtained model, an equivalent SM controller is developed for output current control of the multilevel grid connected inverter. To improve robustness and stability of the system against uncertainty of model parameters, a nonlinear component is added to the equivalent controller.

The proposed controller enjoys very fast dynamic response, so it can be employed in wide ranges of application e.g. reactive compensation and harmonic mitigation modes. In active power filtering operation, it is able to eliminate harmonic components of the grid from 20.61% to 1.34% which is compatible with IEEE and IEC standards.

The stability of the proposed method has also been proved by using the Lyapunov stability theory. The simulation results show that in different operating conditions, the proposed controller has a stable and robust response. 

In Iran, due to population growth and rising costs in the coming years and supply of food needs, there should be solutions for more production, with less waste, so the presence of robots can be justified for more production, reducing waste and reducing current costs. The present study investigates the factors affecting the adoption of automation in agriculture in Ardabil within the framework of the constructive factors of "Technology Acceptance Model" and examining the applicability of this model in the research community.

In the present study, the conceptual model factors include perceived usefulness, perceived ease of use, attitude toward use, and the intention to use, that affect the dependent variable of automation. Six of the first hypotheses of this study are based on the study of the significant relationships between each pair of variables in the framework of the "Technology Acceptance Model", and the applicability of the "Technology Acceptance Model" in the research community is defined in the seventh hypothesis. The method of this research is surveyed and data collection tool is a questionnaire designed based on technology acceptance model (TAM). In this research, the population of 27670 people were investigated that include university staffs-farmers and managers of ministry of agriculture in Ardabil. Using Cochran formula, 380 of them were selected in the form of stratified random sampling as sample size. Validity was confirmed by experts in agricultural management and mechanization, using Cronbach's alpha (0.958). Also, descriptive and inferential statistics were used and data analysis was performed using SPSS20 software.

The findings of this study showed that the technology acceptance model with a final determination coefficient of 635.0 was used in the studied population, which means that the applicability of the model (TAM) was very suitable for agricultural study in Ardabil. The priorities for the effects of the variables of the technology acceptance model for the actual use of automation were perceived ease of use (1.284), perceived usefulness (1.280), intention to use (0.954) and attitude (0.478) respectively.Using the results of modeling, it was also found that the correlation coefficient between individual factors and the perceived usefulness of the application of automation has a strong relationship. The correlation coefficient between the two variables is negative and indicates that with increasing individual factors, the level of perceived usefulness of the use of automation also decreases, and vice versa. However, experience, self-confidence and financial situations, level of education, land area, number of family workforce, have not greatly increased productivity and reduced production costs and helped agricultural activities (understanding the usefulness of technology).The relationship can be considered as the most important factor in holding weak and undesirable classes in creating knowledge, experience and poor self-confidence of the respondents towards accurate agricultural technology. In these classes, the content should be presented in a more specialized and practical way to make them understand the usefulness of precision agricultural technology.According to the results of this study, the organization of workshops and periodic training courses, as well as the introduction of this technology in journals and publications and social media is recommended.

Considering the confirmation of the hypotheses of this research and the priorities obtained for the effects of the structures of the technology acceptance model, it can be concluded that as it is known, the two main constituents of this model, perceived ease of use and perceived usefulness have had a significant impact on the amount of technology used, or, in other words, technology acceptance. The perceived usefulness is the most effective factor in the actual use of automation. In following, perceived ease of use, intention to use, and the attitude was ranked respectively.

In this paper, a novel method for loss reduction and efficiency optimization of the high frequency flyback transformers is proposed based on rearrangement of the windings. According to detailed analysis of the high frequency flyback transformer using FEM technique, a novel and simple approach for its design improvement and loss reduction is introduced. It is shown that leakage flux scattering in core air-gap is one of the main reasons for hot-spot point generation in the windings. So, this problem and its possible solutions are analyzed in more detail. Moreover, FEM analysis is used for investigation of the developed method and rearrangement of the winding structure. In fact, some winding structures for efficiency improvement of the flyback transformer is presented and analyzed. Finally, in order to verify accuracy and effectiveness of the developed approach, simulation and experimental results are presented. Experimental results show 3.3% improvement in total efficiency of the converter and 41.78% loss reduction in the flyback transformer.

The Linear Quadratic (LQ) equation as the most common formula in radiotherapy has a debatable accuracy in modeling high-dose effects. The purpose of this study was to demonstrate bystander response of the Grid treatment in SCC cell line, based on both theoretical calculations and experimental investigations.

The linear quadratic model was used to calculate the equivalent uniform dose (EUD) of a Grid-field with the 10 Gy maximum doses. According to the EUD definition, the identical tumor survival fraction (SF) was expected to obtain from both Grid and open-field single fraction. After observing the difference, the clonogenic and apoptosis assays were exerted to investigate bystander response via medium transfer strategy which was performed from 10Gy-irradiated donors to 1.5Gy-irradiated recipients.

The EUD was equal to 4 Gy and the SF of 4 Gy EUD and 10 Gy Grid-field were 0.1 ± 0.02 and 0.051 ± 0.008, respectively. These findings contradicted the theoretical expectations of their survivals equality. Moreover, the bystander clonogenic cells death enhanced approximately by 2.91 times (statistically significant); highlighting the bystander response role. The apoptotic findings illustrated that the bystander cells experienced an approximately 10% increase and the apoptotic rate confirmed the clonogenic survival result which was less in the EUD than the Grid-field.

Since the SF of the Grid-field was less than the EUD, it revealed the Grid therapeutic advantages plus bystander response manifestation; that was ignored in the LQ equation and may not be demonstrated by sheer theoretical calculations of the modulated-field.

In this research, firstly, a one-dimensional steady state model for a catalytic fixed bed reactor is presented. All mass transfer, heat transfer and momentum equations are considered in this model, applying appropriate assumptions. The results of modeling predict temperature and concentration changes and also pressure drop along the reactor bed length. By applying the modeling, hydrazine catalytic reactor was designed. The design procedure includes thrust and specific impulse and continues with calculation of the bed diameter. Ammonia dissociation and the mass flux were calculated along the length of the bed. Finally, the reactor was designed and tested. In these tests, the maximum reactor temperature was 650 oC, the ammonia dissociation was 59% and the pressure drop was 1.3 bar, presenting a good coherency with the modeling data.

Following the concept of L-limited sets in dual Banach spaces introduced by Salimi and Moshtaghioun, we introduce the concept of almost L-limited sets in dual Banach lattices and then by a class of disjoint limited completely continuous operators on Banach lattices, we characterize Banach lattices in which almost L-limited subsets of their dual, coincide with L–limited sets.

Dried pulps and peels of Ziziphus jujuba fruits are commonly applied as food because of their high nutritional value. It has been widely used in traditional medicine as laxative, tonic, wound healing agent and appetizer. The aim of this study was to evaluate the anti-melanogenic effects of Z. jujuba fruit.

Fruit extracts were obtained by two different extraction methods, percolation (cold extraction) and soxhlet (hot extraction) using methanol 80% as the solvent. The total phenolic and flavonoid contents, DPPH radical scavenging activity and anti-tyrosinase capacity of the MeOH extracts from Z. jujuba fruits were evaluated in vitro. In addition, the effects of fruit extracts on the melanin content and cytotoxicity on human melanoma SKMEL-3 cells were determined after 72 hours.

The amount of total phenolic and flavonoid contents of the cold extract were found higher in comparison to the hot extract. Moreover, the antioxidant (SC50 =1.40 mg/mL) and anti-tyrosinase activities (IC50 = 0.54 mg/mL) of the cold extract were significantly stronger than the hot extract. At the dose of 500 μg/mL, the cold extract showed weaker toxicity to the melanoma cells than the hot extract. Melanin content of the cold extract was reduced to 30% at this concentration, while the hot extract had no inhibitory effect on melanin formation.

The results showed that the percolation method was more suitable for extraction of the (poly) phenolics from Z. jujuba fruits. In addition, the results of tyrosinase activity and melanin content assays suggested that the cold extract of Z. jujuba fruit can be considered as a dermatological whitening agent in skin care products.