Predictions of wet natural gases condensation rates via multi-component and multi-phase simulation of supersonic separators

Seyed Heydar Rajaee Shooshtari,Akbar Shahsavand 한국화학공학회 2014 Korean Journal of Chemical Engineering Vol.31 No.10

Proper correction of water and heavy hydrocarbon dew points of sweet natural gases is essential from vari-ous technical and economical standpoints. Supersonic separators (3S) are proved to be capable of achieving these taskswith maximum reliability and minimal expenses. The majority of the previous articles have focused on the flow behaviorof pure fluids across a 3S unit. Multicomponent fluid flow inside 3S accompanied with condensation phenomenonwill drastically increase the complexity of the simulation process. We tackle this issue by considering a proper com-bination of fundamental governing equations and phase equilibrium calculations to predict various operating conditionsand composition profiles across two multi-component and multi-phase 3S units. Various Iranian sweet gases are usedas real case studies to demonstrate the importance of 3S unit practical applications. Simulation results clearly illustratethe effectiveness of 3S units for faithful dehydration of various natural gases, while successfully controlling its dewpoint, suitable for any practical applications. Conventional HYSYS simulation software is used to validate the simulationresults.

Polymeric membranes for the oxygen enrichment of air in sulfur recovery units: Prevention of catalyst deactivation through BTX reduction

Shooshtari Seyed Heydar Rajaee,Bastani Kiarash,Eslampanah Hamidreza 한국화학공학회 2023 Korean Journal of Chemical Engineering Vol.40 No.12

The modified Claus process is one of the most commonly used methods for hydrogen sulfide conversion into sulfur. However, one of the problems of this unit is the presence of benzene, toluene, and xylene (BTX) compounds at the inlet of the catalytic reactors that can deactivate the catalyst and decrease the efficiency of the sulfur recovery unit. One of the methods of BTX destruction in a furnace is to increase its temperature by increasing the oxygen concentration in the inlet air. In the present work, the application of polymeric membranes for the destruction of BTX was investigated by modeling and simulating a sulfur recovery unit and a membrane unit. The numerical results obtained from the simulations were validated successfully with industrial and experimental data for both sulfur recovery and membrane units. The simulation results for an industrial case study indicate that using five PI carbon membrane units with a total area of 26.82 m2 can increase the concentration of oxygen in the inlet air to a level of 60%. In this condition, the reduction in BTX compounds can also be increased up to 59%. Furthermore, for two-stage membrane configuration, by employing five two-stage membrane units with a total area of 58.3m2, the oxygen concentration increases to 82%, and the reduction in BTX compounds will be 75%.

Effects of Spinal-Z in Patients with Gastroesophageal Cancer

Panahi, Yunes,Saadat, Alireza,Seifi, Maghsoud,Rajaee, Mahdi,Butler, Alexandra E.,Sahebkar, Amirhossein KOREAN PHARMACOPUNCTURE INSTITUTE 2018 Journal of pharmacopuncture Vol.21 No.1

Objective: The purpose of this study was to investigate the efficacy and safety of spinal-Z, derived from Peganum harmala seeds and Dracocephalum Kotschyi Boiss leaves, in patients with esophageal and stomach adenocarcinoma, and squamous cell carcinoma of the esophagus. Methods: Sixty-one patients with malignancies of the upper gastrointestinal tract were randomly assigned to one of two groups (treatment or control) in a double-blind fashion. Six capsules of Spinal-Z were prescribed to the patients with the regimen of 600 mg/m2/day, and placebo to the control group, for six months. Results: There were no significant differences between the two groups with regard to age, sex, duration of cancer, type of cancer and family history of cancer. There were significant differences in abdominal pain, heartburn, constipation and vomiting between the two groups, following spinal-Z therapy. Evaluation of drug side effects showed no difference in cough or other respiratory symptoms, itching, headache or dizziness between the two groups, both before and after treatment. Conclusion: This study indicates that Spinal-Z is safe and efficacious in the management of patients with upper gastrointestinal tract cancers.

Neuroprotective Agents in the Intensive Care Unit -Neuroprotective Agents in ICU -

Panahi, Yunes,Mojtahedzadeh, Mojtaba,Najafi, Atabak,Rajaee, Seyyed Mahdi,Torkaman, Mohammad,Sahebkar, Amirhossein KOREAN PHARMACOPUNCTURE INSTITUTE 2018 Journal of pharmacopuncture Vol.21 No.4

Neuroprotection or prevention of neuronal loss is a complicated molecular process that is mediated by various cellular pathways. Use of different pharmacological agents as neuroprotectants has been reported especially in the last decades. These neuroprotective agents act through inhibition of inflammatory processes and apoptosis, attenuation of oxidative stress and reduction of free radicals. Control of this injurious molecular process is essential to the reduction of neuronal injuries and is associated with improved functional outcomes and recovery of the patients admitted to the intensive care unit. This study reviews neuroprotective agents and their mechanisms of action against central nervous system damages.

Effects of Spinal-Z in Patients with Gastroesophageal Cancer

Yunes Panahi,Alireza Saadat,Maghsoud Seifi,Mahdi Rajaee,Alexandra E. Butler,Amirhossein Sahebkar 대한약침학회 2018 Journal of pharmacopuncture Vol.21 No.1

Objective: The purpose of this study was to investigate the efficacy and safety of spinal-Z, derived from Peganum harmala seeds and Dracocephalum Kotschyi Boiss leaves, in patients with esophageal and stomach adenocarcinoma, and squamous cell carcinoma of the esophagus. Methods: Sixty-one patients with malignancies of the upper gastrointestinal tract were randomly assigned to one of two groups (treatment or control) in a double-blind fashion. Six capsules of Spinal-Z were prescribed to the patients with the regimen of 600 mg/m2/ day, and placebo to the control group, for six months. Results: There were no significant differences between the two groups with regard to age, sex, duration of cancer, type of cancer and family history of cancer. There were significant differences in abdominal pain, heartburn, constipation and vomiting between the two groups, following spinal-Z therapy. Evaluation of drug side effects showed no difference in cough or other respiratory symptoms, itching, headache or dizziness between the two groups, both before and after treatment. Conclusion: This study indicates that Spinal-Z is safe and efficacious in the management of patients with upper gastrointestinal tract cancers.

Modeling of gas permeation through mixed matrix membranes using a comprehensive computational method

Majid Pakizeh,Salman Ofoghi,Seyed Heydar Rajaee Shooshtari 한국화학공학회 2016 Korean Journal of Chemical Engineering Vol.33 No.11

Three different morphologies can occur at the interface of inorganic and polymeric phases in mixed matrix membranes (MMMs). These morphologies are characterized by their different parameters such as partial pore blockage factor (α), polymer chain rigidification factor (β), and thickness of rigidified layer or void region. In this study, the morphology of three MMMs has been evaluated using a comprehensive computational method. The average absolute relative error (%AARE) is used as a criterion for optimizing three various MMM morphological parameters. According to the obtained optimum parameters, it was confirmed that two MMMs of C60/Matrimid and PVAc-Zeolite 4A have pore blockage and polymer chain rigidified defects. The results show that the morphology of ZIF-8/6FDA-DAM can be considered as an ideal morphology. After obtaining the morphological parameters, the permeability of the studied MMMs was predicted based on the modified Maxwell model and good agreement was observed between the calculated value and the experimental data.

Neuroprotective Agents in the Intensive Care Unit -Neuroprotective Agents in ICU -

Yunes Panahi,Mojtaba Mojtahedzadeh,Atabak Najafi,Seyyed Mahdi Rajaee,Mohammad Torkaman,Amirhossein Sahebkar 대한약침학회 2018 Journal of pharmacopuncture Vol.21 No.4

Neuroprotection or prevention of neuronal loss is a complicated molecular process that is mediated by various cellular pathways. Use of different pharmacological agents as neuroprotectants has been reported especially in the last decades. These neuroprotective agents act through inhibition of inflammatory processes and apoptosis, attenuation of oxidative stress and reduction of free radicals. Control of this injurious molecular process is essential to the reduction of neuronal injuries and is associated with improved functional outcomes and recovery of the patients admitted to the intensive care unit. This study reviews neuroprotective agents and their mechanisms of action against central nervous system damages.

Study on resonant electron cyclotron heating by OSXB double mode conversion at the W7-X stellarator

S. Adlparvar,S. Miraboutalebi,S.M. Sadat Kiai,L. Rajaee 한국원자력학회 2018 Nuclear Engineering and Technology Vol.50 No.7

Electromagnetic waves potentially have been used to heat overdense nuclear fusion plasmas through adouble mode conversion from ordinary to slow extraordinary and finally to Electron Bernstein Wave(EBW) modes, OSXB. This scheme is efficient and has not any plasma density limit of electron cyclotronresonance heating due to cut-off layer. The efficiency of conversion depends on the isotropic launchingangles of the microwaves with the plasma parameters. In this article, a two-step mode conversions ofOSXB power transmission efficiency affected by the fast extraordinary (FX) loses at upper hybrid frequencyare studied. In addition, the kinetic (hot) dispersion relation of a overdense plasma in a full waveanalysis of a OSXB in Wendelstein 7X (W7-X) stellarator plasma has been numerically simulated. Theinfluence of plasma dependent parameters such as finite Larmor radius, electron thermal velocity andelectron cyclotron frequency are represented.

Evaluation of Manganese, Boron, Potassium, Calcium and Zinc Effects on Yield and Fruit Quality of Barberry (Berberis vulgaris L.) Plants

Khayyat Mehdi,Mahmoodabadi Mohammad Reza,Khayyat Ali Reza,Rajaee Soheila 한국원예학회 2008 Horticulture, Environment, and Biotechnology Vol.49 No.5

The present research was carried out to investigate the effects of some macro and micronutrients on fruit quality and quantity in barberry (Berberis vulgaris L.) plants. Treatments included manganese (Mn 20 and 40 ㎎ㆍL?¹), potassium (K 1 and 2%), calcium (Ca 2 and 3%), boron (B 1000 and B 2000 ㎎ㆍL?¹), zinc (Zn 300 and 600 ㎎ㆍL?¹) and water (W). The highest and lowest yields were obtained by W and Ca 2%, respectively. Moreover, the highest and lowest fruit numbers resulted from B 2000 ㎎ㆍL?¹ and Ca 2% treatments, respectively. Although high amount of vitamin C was resulted from Ca treatments, high concentration of total acid (TA) and soluble solids concentration (SSC) were found in K treatments. The results of these studies showed that mineral nutrients via spray can alter the yield and quality of barberry fruits.

Phytoplankton in tropical mangrove estuaries: role and interdependency

A.S.M. Saifullah,Abu Hena Mustafa Kamal,Mohd Hanafi Idris,Amy Halimah Rajaee,Md. Khurshid Alam Bhuiyan 한국산림과학회 2016 Forest Science And Technology Vol.12 No.2

Mangrove estuaries are claimed to be productive and important breeding grounds for fishery resources. The role of particulate organic matter (POM), especially derived from decomposed litter detritus, is well documented in mangrove estuaries. However, being a primary producer, phytoplankton may play a significant role, which has not been well discussed, in governing the productivity of mangrove estuaries. Based on relevant published literature, this paper focuses on the role of phytoplankton in mangrove estuaries in the tropical coastal region and their interdependency. Analysis reveals that there are two-way interactions between phytoplankton and mangrove estuaries. The POM enriched water in mangrove estuaries acts as an ideal medium for phytoplankton succession. Simultaneously, diversified phytoplankton assemblages play a significant role in the food web of the estuarine mangrove ecosystem. Biomass and diversity of phytoplankton are influenced by nutrient and environmental parameters in mangrove estuaries and, concurrently, phytoplankton play a significant role in fish diversity and primary production in the same system. This review reveals that the inconsistent relationships between mangroves and coastal production could probably be due to the influence of seasonal changes. This paper unveils the latent potential and role of phytoplankton in tropical mangrove estuaries, which could be a source of thought for future research in this arena.