Solubility of ethylene in N-methyl-2-pyrrolidone: Experimental study and estimation of UNIQUAC activity model parameters

Mohammad Yousefi,Shima Azizi,Seyed Mohsen Peyghambarzadeh,Zoha Azizi 한국화학공학회 2021 Korean Journal of Chemical Engineering Vol.38 No.4

The solubility of ethylene in N-methyl-2-pyrrolidone (NMP) was evaluated at different temperatures, including 278.2, 298.2, and 328.2 K, and different pressures in an experimental pressure decaying setup. The kinetic and equilibrium results were obtained for pure gas absorption. Henry’s law constants were calculated at different temperatures. Eventually, thermodynamic modeling was done using Peng Robinson equation of state (PR-EOS) and UNIQUAC activity coefficient model. The binary interaction parameters, 12, 21, were adjusted and optimized. Regarding the values obtained for binary interaction parameters, it was concluded that this solution has non-ideal behavior. Indeed, because of its low prediction error (3-11%), it was concluded that the correlated thermodynamic model could accurately predict the experimental data.

A systematic investigation of experimental conditions on the particle size and structure of TiO2 nanoparticles synthesized by a sol-gel method

Roohollah Azizi,Sousan Rasouli,Naghi Parvini Ahmadi,Amin Jafari jafar kolaei,Mohammad Azizi 한양대학교 세라믹연구소 2012 Journal of Ceramic Processing Research Vol.13 No.2

TiO2 nanoparticles were prepared by a sol-gel method using TiCl4 as a precursor. The effect of the TiCl4/H2O molar ratio and DBS/ethanol (two important parameters in this process) on the particle size and structure of the samples were studied. The structure and morphology of the nanoparticles were investigated by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. A systematic study was made by using the results of Design-Expert software. The optimum ratio of TiCl4/H2O and DBS/ethanol, to achieve the smallest particle size and the highest rutile content, were studied. Results showed that a lower TiCl4/H2O molar ratio led to smaller nano particles and that this goal is achieved for the lowest TiCl4/H2O molar ratio and intermediate DBS/ethanol values.

A new ternary mixed-matrix membrane (PEBAX/PEG/MgO) to enhance CO2/CH4 and CO2/N2 separation efficiency

Azizi Navid,Jahanmahin Omid,Homayoon Reza,Khajouei Mohammad 한국화학공학회 2023 Korean Journal of Chemical Engineering Vol.40 No.6

Mixed-matrix membranes (MMMs) composed of suitable CO2-philic polymers and fillers can be attractive candidates for CO2/CH4 and CO2/N2 separation due to their high CO2 permeability, good thermochemical stability, low fabrication cost, and fast production process. In this research, a novel ternary MMM was fabricated via the blending of poly (amide 12-b-ethylene oxide) (PEBAX-1074) with polyethylene glycol (PEG-200) and magnesium oxide (MgO) nanoparticles mixture. The effects of various loadings of the fillers on CO2, N2, and CH4 permeability values through the membranes were studied. Permeation of CO2, N2, and CH4 gases through the resultant membranes at pressures of 2, 4, 6, 8, and 10 bar and temperatures of 25, 35, 45, and 55 °C revealed the superiority of the MMMs for CO2/CH4 and CO2/N2 separation in comparison with the pristine membranes. Particularly, at 25 °C and 2 bar, the CO2 permeability, as well as ideal CO2/CH4 and CO2/N2 selectivity of the optimized MMM containing 40 wt% of PEG-200 and 8 wt% of MgO nanoparticles, rose to 210.1 Barrer, 24.9 and 60.9, corresponding to enhancement of around 225%, 23% and 24% of the CO2 permeability and selectivity compared to the neat membrane, respectively. Thus, the fabricated MMM has a satisfying potential to separate CO2 from N2.

Antiglycation and antioxidant activity of four Iranian medical plant extracts

Mohammad Reza Safari,Omid Azizi,Somayeh Sadat Heidary,Nejat Kheiripour,Alireza Pouyandeh Ravan 대한약침학회 2018 Journal of pharmacopuncture Vol.21 No.2

Objective: Diabetes mellitus (DM) is the most common metabolic disorder that defined by chronic hyperglycemia for the deficiency in insulin secretion or resistance. Hyperglycemia could induce non-enzymatic glycation of proteins. It has been suggested that some traditional plants can improve blood glucose and inhibit glycation process. This work evaluates and compares the anti-glycation activities of four Iranian plant extracts in vitro. Methods: The methanolic extract of “Fumaria officinalis, Stachys lavandulifolia, Salvia hydrangea and Rosa Damascene” was prepared in three different concentrations. Phenolic, flavonoids content and antioxidant activity were evaluated. The multistage glycation markers- fructosamines (early stage), protein carbonyls (intermediate stage) and β aggregation of albumin were investigated in the bovine serum albumin (BSA)/ glucose systemt. Results: All plants showed the high potency of scavenging free radicals and glycation inhibition in the following order: Fumaria officinalis> Rosa Damascene> Stachys lavandulifolia > Salvia hydrangea. There was a significant correlation between antioxidant and anti-glycation activity. Also, the antioxidant and anti-glycation capacity of extracts correlated with total phenolic and flavonoids content. Conclusion: Our findings demonstrated that the studied plants are good sources of anti-glycation and antioxidant compounds and, these properties can primarily attributable to phenolics, particularly flavonoids.

Evaluation of Three Support Shapes on Behavior of New Bolted Connection BBCC in Modularized Prefabricated Steel Structures

Alifazl Azizi Naserabad,Mohammad Reza Ghasemi,Naser Shabakhty,Hammed Ghohani Arab 한국강구조학회 2018 International Journal of Steel Structures Vol.18 No.5

Bolted connections are suitable due to high quality prefabrication in the factory and erection in the workplace. Prefabrication and modularization cause high speed of erection and fabrication, high quality and quick return of investment. Their technical hitches transportation can be removed by prefabrication of joints and small fabrication of components. Box-columns are suitable members for bolted structures such as welded steel structures with moment frames in two directions etc., but their continual fabrication in multi-story buildings and performing the internal continuity plate in them will cause some practical dilemmas. The details of the proposal technique introduced here, is to remove such problems from the box columns. Besides, some other advantages include new prefabricated bolted beam-to-column connections referred to BBCC. This connection is a set of plates joined to columns, beams, support, and bolts. For a better understanding of its fabrication and erection techniques, two connection and one structural maquettes are made. The present work aims to study the cyclic behavior of connection numerically. To verify the accuracy of model, a similar tested connection was modelled. Its verifi cation was then made through comparison with test results. The behavior of connection was evaluated for an exterior connection using three diff erent support shapes. The eff ects of support shapes on rigidity, ductility, rotation capacity, maximum strength, four rad rotation strength were compared to those of the AISC seismic provision requirements. It was found that single beams support has all the AISC seismic provision requirements for special moment frames with and without a continuity plate, and box with continuity plate is the best support in the BBCC connection.

Antiglycation and antioxidant activity of four Iranian medical plant extracts

Safari, Mohammad Reza,Azizi, Omid,Heidary, Somayeh Sadat,Kheiripour, Nejat,Ravan, Alireza Pouyandeh KOREAN PHARMACOPUNCTURE INSTITUTE 2018 Journal of pharmacopuncture Vol.21 No.2

Objective: Diabetes mellitus (DM) is the most common metabolic disorder that defined by chronic hyperglycemia for the deficiency in insulin secretion or resistance. Hyperglycemia could induce non-enzymatic glycation of proteins. It has been suggested that some traditional plants can improve blood glucose and inhibit glycation process. This work evaluates and compares the anti-glycation activities of four Iranian plant extracts in vitro. Methods: The methanolic extract of "Fumaria officinalis, Stachys lavandulifolia, Salvia hydrangea and Rosa Damascene" was prepared in three different concentrations. Phenolic, flavonoids content and antioxidant activity were evaluated. The multistage glycation markers- fructosamines (early stage), protein carbonyls (intermediate stage) and ${\beta}$ aggregation of albumin were investigated in the bovine serum albumin (BSA)/ glucose systemt. Results: All plants showed the high potency of scavenging free radicals and glycation inhibition in the following order: Fumaria officinalis> Rosa Damascene> Stachys lavandulifolia > Salvia hydrangea. There was a significant correlation between antioxidant and anti-glycation activity. Also, the antioxidant and anti-glycation capacity of extracts correlated with total phenolic and flavonoids content. Conclusion: Our findings demonstrated that the studied plants are good sources of anti-glycation and antioxidant compounds and, these properties can primarily attributable to phenolics, particularly flavonoids.

The Effects of Nigella sativa Supplementation on Liver Enzymes Levels: a Systematic Review and Meta-analysis of Randomized Controlled Trials

( Neda Azizi ),( Mohammad Reza Amini ),( Kurosh Djafarian ),( Sakineh Shab-bidar ) 한국임상영양학회 2021 Clinical Nutrition Research Vol.10 No.1

The present systematic review and meta-analysis aimed to investigate the effects of Nigella sativa (N. sativa) supplementation on liver enzymes levels including aspartate aminotransferase (AST) and alanine aminotransferase (ALT). Relevant studies, published from inception up to January 2020, were searched through PubMed, Scopus and Google Scholar conducted on randomized controlled trials (RCTs) investigating the effect of N. sativa on serum AST and ALT levels. Meta-analysis was applied using a random-effects model. Eight studies met inclusion criteria (n=281 in the N. sativa and n = 279 in placebo group). This meta-analysis showed that N. sativa supplementation significantly reduced AST level (weighted mean difference [WMD], -8.11 IU/L; 95% confidence interval [CI], -13.6, -2.53; p = 0.004) with significant heterogeneity (I-squared, 95.9%; p < 0.001) while the decrease in ALT level was not statistically significant (WMD, -7.26 IU/L; 95% CI, -15.4, 0.04; p = 0.051) with significant heterogeneity (I-squared, 97.8%; p < 0.001). This meta-analysis suggests that N. sativa supplementation may improve AST levels and ALT levels, however more RCTs with larger sample size are needed to found effects of N. sativa on liver enzymes in patients with non-alcoholic fatty liver disease.

Stability analysis of a parametrically excited functionally graded piezoelectric, MEM system

Saber Azizi,Mohammad-Reza Ghazavi,Siamak Esmaeilzadeh Khadem,Jie Yang,Ghader Rezazadeh 한국물리학회 2012 Current Applied Physics Vol.12 No.2

In this paper the mechanical behavior of a parametrically actuated functionally graded piezoelectric (FGP) clampedeclamped micro-beam is investigated. The micro-beam is supposed to be a composite material with silicon and piezoelectric base. The mechanical properties of the structure, including elasticity modulus, density, and piezoelectricity coefficient are supposed to vary along the height of the micro-beam with an exponential functionality. It is supposed that the FGP clampedeclamped microbeam is actuated with a combination of direct and alternative electric potential difference. Application of DC and AC actuation voltage leads in a constant and a time-varying axial force. The governing differential equation of the motion is derived using Hamiltonian principle and discretized using expansion theorem with the corresponding shape functions of a clampedeclamped beam. The discretized system is governed by Mathieu equation which’s stability is investigated using Floquet theory for single degree of freedom systems and verified using multiple time scales of perturbation technique.

The Accumulation of Al, As, Li, Mg, Mn, S, Si, Ti, and V in the Mussel Mytilus galloprovincialis from the Moroccan Mediterranean Coastal Areas: Trends Pertaining to Seasons and Levels

Ghizlane Azizi,Mostafa Layachi,Mustapha Akodad,Mourad Baghour,Mohammad Ghalit,Elkhadir Gharibi,Hamza Ngadi,Abdelmajid Moumen 한국해양과학기술원 2020 Ocean science journal Vol.55 No.3

The accumulation levels of elements (Al, As, Li, Mg, Mn, S, Si, Ti, and V) in the soft tissue of mussels (Mytilus galloprovincialis), collected monthly in 2016, from Junuary to December, from sampling sites of the mussel farming facilities installed in the coastal areas of Al Hoceima, were investigated. The studied element levels were determined by using Inductively Coupled Plasma - Optical Emission Spectrometry (ICP-OES 720-ES). Descending order of the average element concentrations in soft tissue ofM. galloprovincialiswas S > Mg > Si> Al > Mn > Ti > As >V > Li. Element contents (Al, As, Mg, S and V) in tissue of mussels were significantly different (P < 0.05) between seasons, being highest in winter and lowest in summer. Strong correlations were observed between studied elements and chlorophylla, indicating the importance of food for metal bioaccumulation in mussels in this period of the season. The observed strong correlations for metal levels in tissues of mussels can be explained by their common sources, which are associated with anthropogenic effects. The detected seasonal variations of investigated element concentrations in soft tissues ofM. galloprovincialiscould be attributed to physicochemical parameters such as temperature, salinity, dissolved oxygen, nutrients and food availability, as well as the biological status of the mussel. This study may provide basic information for detecting the current pollution status of investigated elements in Al Hoceima coasts from the Moroccan Mediterranean Sea usingM. galloprovincialisas biological indicators.

Design of a Novel Prefabricated Bolted I-Beam to Box-Column Connection Using Numerical Analysis Under Cyclic Load

Alifazl Azizi Naserabad,Mohammad Reza Ghasemi,Naser Shabakhty,Hamed Ghohani Arab 한국강구조학회 2019 International Journal of Steel Structures Vol.19 No.5

The proposed prefabricated bolted beam-to-column connection (BBCC) has been introduced to remove the problems of continuous/box columns and to show such merits as high-quality factory fabrication, easy transportation/erection/resumption, investment return, prefabrication, and modularization; this paper aims at designing and numerically studying the cyclic behavior of the novel designed connections. To this end, fi rst the technical requirements and the design formulas are presented; three sample connection are designed; a similar connection was modeled, and the numerical and experimental results were compared and validated. Then, three design models were made to study the behavior of the exterior connections under cyclic load. The bases adopted for the model behavior were the AISC seismic provision requirements. The results show that all the AISC specifi c moment frame requirements including the failure mode, rigidity, ductility, moment capacity, rotational capacity, and ultimate rotation were met and the accuracy of design formulas are achieved.