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Research subject: Osmosis membrane bioreactor is one of the best industrial wastewater treatment methods. The main advantage of using osmosis process is its operation at low hydraulic pressures which has a better performance in removing pollutants and low energy consumption than other methods                        
Research approach: In this research, Nano porous Titanium dioxide powder with a specific surface area and anatase wall was synthesized through a thermal process using cetyltrimethylammonium bromide (CTAB) as a surfactant directing agent and a pore-creating agent.Ultrafiltration nanocomposite membranes were made using modified titanium dioxide (TiO₂) (MT) and polysulfone (PSf) by phase the inversion method. The morphology and structure of the prepared membranes and nanoparticles were investigated using by atomic fourier transforms infrared spectroscopy(FESEM), X-ray diffraction (XRD) and transmission electron microscopy (TEM). In this research, bovine serum albumin (BSA) was used as simulated wastewater for the feed solution. The fabricated ultrafiltration membranes were tested in osmosis membrane bioreactor (OMBR) system due to lower energy and fouling. 0.6 % solution of poly (sodium 4-styrene sulfonate) was used as an osmotic solution. Comparative separation performance and antifouling properties of both nanocomposites in several analyzes such as water contact angle measurement, pure water flux and filtration of different concentrations of bovine serum albumin solution. BSA and fouling resistance have been investigated


Main results:  TThe results that Due to the addition of MT nanoparticles to the polymer matrix, the hydrophilicity and surface energy of the membrane increased, which led to the improvement of the membrane performance. The membrane containing 1% titanium oxide nanoparticles showed the best result. For example, for feeding with a concentration of 200 ppm, the water flux increased from 20 to 38.5 L/ m² h, and the percentage of returning lethal solution decreased from 19.6 to 30 g/ m² h. The flux recovery in this membrane was 96%, which indicates the antifouling property of the modified nanocomposite membrane.                                                                
              

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On one hand, the skill-based technologies increase productivity and output, reduce inflation and raise income. On the other hand, human skills are essential for implementing, adopting, utilizing physically and practically of modern and imported technologies and serve a complementary role in this respect. In the present paper, an attempt has been made to evaluate the relationship between the domestic research and development capital stock and technology imports with skilled and unskilled workers in Iran from 1971 to 2006. To do this, a translog cost function was estimated with seemingly unrelated regression method. The results indicate that the technology and its spillover are complementary to the skilled labor and substitute for the unskilled worker. In addition, the results illustrate the existence of a complementary relationship between capital and skilled labor and a substitution one with capital and unskilled worker.

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Despite the relative success of different chemical compounds to improve meat tenderness, adverse effects caused by the use of these compounds on the physicochemical and sensory characteristics of meat, have led to restrictions on their use on an industrial scale. Therefore, in order to prevent these undesirable chemical effects, the application of some natural tenderizers has been considered. Natural meat tenderizers, are substances in those fruits and vegetables containing proteolytic enzymes such as cysteine protease, serine protease, metalloprotease and aspartic proteases. In this paper major biochemical changes that have led to meat tenderness, as well as proper plant sources used in tenderizing process have been reviewed.

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Introduction:
According to the models of growth, renewable and non-renewable energy  affect economic growth, but the consumption of renewable energy due to less pollution, contributes to sustainable growth. So, countries strive to create the conditions for the use of renewable energy, such as electricity. By balancing competition in market such as the electricity market, on the micro level surplus of consumer and producer welfare is maximized without government intervention, and the incentive for the private sector to enter the market increases. On the macro level, due to lower prices and increased production, electricity consumption as renewable energy increases and reduces environmental degradation and increases sustainable growth. Over the past decades, in the electricity industry, natural monopoly conditions have been established in the sectors of production, transmission and distribution, and the surplus of consumer and producer welfare has not been maximized, so government intervention was justified. In recent years, due to technological advances and the elimination of natural monopolies, the incentive for the private sector to enter the electricity sector has been strengthened. The purpose of this article is to measure the degree of competition in 9 electricity companies in Iran during the period 2011-2019.

Methodology: 

In order to measure the degree of competition in Iran's electricity industry, two structural approaches, i.e., Entropy coefficient and non-structural Panzar-Rosse were used. 

The entropy measure is used as an alternative to variance, in fact entropy is the inverse measure of concentration, when entropy increases, concentration decreases:
E=i=1nSi.log1Si    ,    0≤E≤log⁡(n)                                                         (1)
Si  is the market share and the value of this index is equal to zero for the monopoly market and increases nonlinearly as the market becomes more competitive.
Measurement of degree of competition by Panzar-Ross method, using the GMM method is as fallows:
LnTRit=α0+α1LnQit+βLLnWLit+βKLnWKit+βELnWEit    (2)  

WLit
  is the labor input price, WKit
  is the capital input price, WEit
  is the energy input price of the power generation company i in the time period t. TRit
  is total revenue, Qit
  is production of the i-th power generation company at time t. In the dynamic specification, the Panzar-Rosse criterion for evaluating the market structure is defined as follows:

PRH=i=13βi1-α1                                                                                                       (3)
If i=13βi=1 , the market is competitive and a decrease (increase) in the price of inputs causes the same decrease (increase) in marginal cost and marginal revenue. If 0<i=13βi<1 , the market has monopolistic competition and is between competition and monopoly.

Results and Discussion:

The calculation of entropy coefficient, which is one of the structural methods in measuring competitiveness, obtained a number equal to 0.215 for the Iranian electricity industry during 2011-2019. Considering that the mentioned number is between zero and one, it shows that the concentration in Iran's electricity industry has decreased during the period under review and this industry has been placed in a state between competitive and monopoly. In other words, the conditions of the electricity industry have moved out of the traditional state and full monopoly, although it still needs to establish arrangements to become more competitive and close to full competition. On the other hand, Panzar-Rosse non-structural method was also estimated and its index was calculated, which obtained a value of 0.253. This amount of Panzar-Rosse non-structural index also confirms the results of the non-structural approach in Iran's electricity industry. Due to the fact that the results of both structural and non-structural approaches in calculating the level of competitiveness in Iran's electricity industry confirm each other, more confidence is created regarding the obtained result.

Conclusion: 

Considering the important and effective role of electricity in other industries of the country, the existence of more competition that leads to a decrease in the price and increase in the production of electricity, from a micro point of view, it has led to an increase in consumer and producer surplus, and from a macro point of view, it has also led to a reduction in environmental pollution. Reducing the exploitation of non-renewable energies and as a result of intergenerational justice and ultimately the realization of sustainable growth and development. Although the results of the calculation of competitiveness indicators indicate that the electricity industry is moving away from the monopoly state and moving towards the competitive state, more efforts should be made in order to increase the degree of competition and achieve complete competition in the country.

 In this way, the country's economic managers and policy makers should increase the number of power plants in Iran's electricity network while removing the existing legal obstacles on the path of restructuring from monopoly to full competition in the country's electricity industry in order to reduce the level of concentration and monopoly in Iran's electricity market. On the other hand, creating a suitable environment for the correct and healthy competition of electricity companies, improving the productivity of production inputs and using the optimal combination of inputs through research and development, as well as short-term and long-term planning to improve the level of production and improve the cost structure, and encouraging and supporting elites and inventors in line with the development of new electricity production plans and technologies such as solar electricity technology can help to make the structure of the electricity industry more competitive.