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A bench scale aerobic sequencing batch reactor (SBR) was evaluated in terms of its potential to treat synthetic dairy wastewater. The 2-l plexiglass bioreactor was supplied with oxygen via a fine bubble air diffuser, fed with synthetic dairy wastewater under various operational conditions. To analyze the process, three significant independent variables — influent chemical oxygen demand (COD), mixed liquor volatile suspended solids (MLVSS), and aeration time — were assessed. Three dependent process and quality parameters (as process responses) were also evaluated: total COD removal efficiency, sludge volume index (SVI) and final pH. The experiments were based on a central composite design (CCD) and analyzed using response surface methodology (RSM). The treatment was limited to the following concentration regimes: COD (1000, 3000 and 5000 mg/l), MLVSS (3000, 5000 and 7000 mg/l) and aeration time (2, 10 and 18 h). Maximum COD removal efficiency (of 96.5%) was obtained for an influent with the following characteristics: CODin: 3000 mg/l, MLVSS 5000 mg/l, and aeration time of 18 h. The study demonstrated the capability of aerobic SBRs for high COD removal from dairy industrial wastewater. Easy operation, low cost, and minimal sludge bulking condition were some of advantages of the SBR system as an option for biological treatment of medium-strength industrial wastewater. The present study provides valuable information about relationships between quality and process parameters for different values of operating variables.

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Prelude: Due to the special characteristics and conditions of Security of the border, deployment of security in such areas is important.any form of insecurity in a border zone can seriously threaten different aspects of security in the country. Deployment of security along the border and in the border zone requires in the first place, investigation, and identification of natural and human-made features within the border zone. identification of natural and geographic features of a border zone is of paramount importance owing to the crucial role played by such bio-foundations in the social life and development of the border zone. They further contribute largely to borderline monitoring, management, and control systems.
Goal: The present research seeks to investigate the states of natural features, including the border stream, topography, and vegetation, in the Iran-Afghanistan border zone in Khorasan Razavi and further evaluates their impact on borderline and border zone security. materials and ways: the required data was extracted from the OLI sensor on the Landsat Satellite(2018), with the data then analyzed using GIS and remote sensing techniques in the ENVI )5.3(.
Conclusion: The findings showed that water scarcity and insufficient depth of Harirood River in most parts of the year set the scene for illegal trafficking of goods and drugs across the border, negatively impacting the border zone security. This further holds true for the seasonal lake of Namakar in the border zone between the two countries. Considering the topography, existing maps indicate that the presence of highlands in the vicinity of the Iran-Afghanistan borderline and extension of particular highlands into the mainland of Afghanistan have negatively influenced the border security.

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China has launched the Silk Road Rehabilitation Project, a "one-way belt project," as a comprehensive regional project. The main goal of this project is to enhance the level of development of the countries between the eastern and western borders of Eurasia by facilitating regional cooperation and developing the infrastructure of the transit countries. The project has two routes: the Silk Road Economic Belt and the 21^st Century Maritime Silk Road. The one-way belt project has various geopolitical, economic, political and commercial dimensions. Areas of non-economic cooperation within the framework of this project include: ensuring the security of trade routes, strengthening counterterrorism cooperation at the regional level, designing mechanisms for resolving disputes over land and sea disputes, developing marine resources, and cooperating in the field of environmental protection and increasing in cultural exchanges. This study using the descriptive- analytic method explains the geopolitical position of Chabahar port in China’s Maritime Silk Road in the 21^st Century.

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Problem design : The present study was conducted with the aim of investigating the relationship between the activity of users in Telegram and Instagram social networks and their political activism in the cities of Tehran as the political-economic capital and Qom as the cultural-religious capital of the country.
Method : This study was carried out using a combined method including library study and survey using a questionnaire tool. The validity of the questionnaire was calculated by the face validity method and its reliability by Cronbach's alpha. The statistical population of this research is all members of Telegram and Instagram social networks over 15 years of age who live in Tehran and Qom, and 768 people were selected as a sample using Cochran's sampling formula and using cluster sampling. were selected
Findings : The results of this research show a significant relationship between the two variables of activity in social networks and political activism of users, and the Spearman statistic at the 95% significance level is 0.24.
Results : Currently and based on the statements of the respondents, users are doing conventional political activism. However, if legal channels are closed for political activism, it can be predicted that unconventional methods of activism such as civil disobedience, protests, strikes, etc. will be used by activists.
 

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Pacts can assist member countries in achieving foreign policy objectives and securing national interests. These pacts have diverse and numerous functions, influenced by geopolitical indicators to varying degrees. Naturally, their impact extends across national, local, regional, and transregional levels. Therefore, this research focuses on examining and analyzing the geopolitical indicators used in power calculations. The functions of pacts can manifest in significant political, security, economic, commercial, cultural, and social dimensions, and they can be applied in regional pacts.
This analytical-descriptive study relies on library resources, documents, articles, and relevant websites for data collection. Additionally, a structured questionnaire was prepared to gather experts' opinions on the analysis of geopolitical indicators for membership in regional pacts. Finally, the collected data underwent analysis using SPSS software and relevant tests. The study also strives to weigh countries' membership in regional pacts based on political, security, economic, commercial, cultural, and social components, and the impact of geopolitical indicators at various levels on the countries' membership process to regional pacts.

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If the technology gap between counties is narrow, the foreign direct investment (FDI) will have a ‎greater impact on total factor productivity (TFP) because of technological spillovers. In this ‎study, regarding the technology gap, the impact of FDI from nine selected OECD countries on ‎TFPs in eight industrial subsectors of Iran is examined using panel threshold model during ‎‎2002-2015. To estimate this model, at first step, a Cobb-Douglas production function was ‎estimated by ARDL approach, and TFPs were calculated. Then, technology gap as ratio of ‎foreign to domestic TFPs were computed. The estimation of panel threshold ‎model ‎indicated that if technology gap between FDI recipients and donors is narrow, the effect ‎of FDI on TFP will be high in industrial subsectors.  In addition, estimating the coefficients of ‎the variables independent of the regime indicated interesting results contrary to the theoretical ‎expectations about the productivity of the industrial sector. The human capital and R&D ‎expenditure had insignificant coefficients. These findings can be can be justified with the low ‎quality of human capital, inadequate expenditure of industrial sector on R&D activities, and ‎economic sanctions which raise the uncertainty and worsen the stagnation. Upgrading human ‎capital in the industrial sector through on-the-job training, or encouraging workers to participate ‎in overseas training courses are recommend to reduce the technological gap and to improve the attraction of FDI.‎

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