Modelling of batch biomethanation process for maximizing income based on values of consumed and produced gases

Seyed Ali Jafari,Shahriar Osfouri,Reza Azin 한국화학공학회 2020 Korean Journal of Chemical Engineering Vol.37 No.5

Economic estimation of an environmental-friendly biomethanation process based on economic values of consumed and produced gases would be a unique attitude. In this paper, time and space dependent concentration profiles of components involved in a batch process, designed for biomethanation, were predicted through a mass transfer modelling. The reaction terms used in the modeling required bio-kinetic parameters of max, m, kL, YC/L, YX/L, and YP/L which were globally optimized via a predefined algorithm using some experimental data as 0.0987 day1, 0.1374 day1, 1.5422mole m3, 1.3636, 0.0183, 0.0908. Upon model verification, process income was calculated for a long-term scenario under a variety of factors and maximized through response surface methodology. The maximum income achieved was $0.4/m3 bioreactor. A term carbon subsidy was considered in the income equation in order to find a break-even income for subsidy value of $363/ton CO2. Sensitivity analysis revealed that the amount of carbon subsidy directly influenced the selection of low or high levels of some process parameters to make the process profitable. In addition, it was found that pressure and liquid volume were the most important factors to achieve maximum income when $30 and $300/ton CO2 carbon subsidy were allocated to the process, respectively.

Cadmium removal from aqueous solution by brown seaweed, Sargassum angustifolium

Seyed Ali Jafari,Abbas Jamali,Asma Hosseini 한국화학공학회 2015 Korean Journal of Chemical Engineering Vol.32 No.10

Four kinds of indigenous seaweed were employed for assessing their soluble cadmium biosorption performance. Sargassum angustifolium revealed the greatest capacity in the range of equilibrium cadmium concentration lower than 0.5mmol l−1. It was further examined by optimization, equilibrium, kinetic and thermodynamic studies. It was found that1 g l−1 biosorbent at initial pH of 6 and 38 oC revealed the highest Cd2+ uptake. Kinetic studies revealed that the Cd2+ biosorption included a two-stage mechanism with an initial rapid stage during the first 30 min where ion exchange was the dominant mechanism. The process gradually reached equilibrium after 40-50 min of contact where the metal adsorption occurred too low due to the intraparticle diffusion. However, it was not the sole rate-limiting step. The pseudo-second order kinetic model, unlike the pseudo-first order, excellently described the experimental data in the whole range of contact time. The Langmuir isotherm model was more successful in describing the equilibrium data than the Freundlich and D-R models. Using this isotherm model, a relationship was proposed to predict the dose of biosorbent needed for removing specific initial cadmium concentration from aqueous solution or to meet a desire equilibrium cadmium concentration. The spontaneity and endothermicity as well as increasing randomness at the solid/solution interface during the biosorption were revealed by means of the thermodynamic studies.

A microlagal-based carbonaceous sensor for enzymatic determination of glucose in blood serum

Seyed Mostafa Jafari,Saeed Masoum,Seyed Ali Hosseini Tafreshi 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.101 No.-

In the present work, Chlorella vulgaris, a well-known microalga was used as a carbonic precursor, tosynthesis the water-soluble carbon dots (CDs) via hydrothermal method. To improve the properties,acidic carbon dots (ACDs) were also synthesized via ultrasoncation of microalgal biomass after acidichydrolysis (using diluted acidic solution). The aqueous solution of ACDs was used as a sensor for glucosedetermination based on glucose oxidase enzyme (GOx) reaction and fluorescence quenching of ACDs inthe presence of Fe3+ ions under the optimized conditions. The linear range of glucose in the blood serumwas measured from a range of 5 mM to 500 mM with a limit of detection (LOD) 2.84 mM. Additionally, thehydrogen peroxide, as the conventional reactive oxygen species (ROS) was determined based on theFenton reaction. The linear range of H2O2 was obtained from 10 mM to 200 mM with LOD of 975 nM. Inall of these applications, fluorescence quenching of ACDs was followed according to photo-inducedelectron transfer (PET) mechanism in the presence of generated Fe3+ ions by Fenton reaction.

Continuous cadmium removal from aqueous solutions by seaweed in a packed-bed column under consecutive sorption-desorption cycles

Seyed Ali Jafari,Abbas Jamali 한국화학공학회 2016 Korean Journal of Chemical Engineering Vol.33 No.4

Packed-bed column process efficiency for cadmium adsorption from aqueous solution was investigated under different bed heights (2.6 to 7.5 cm) and feed flow rates (15 to 30 ml min−1). The column was filled with brown seaweed, Sargassum angustifolium. Three simplified models, including Bed Depth Service Time, Thomas, and Yoon- Nelson were employed for describing the experimental breakthrough curves as well as achieving design parameters. Bed lifetime was also evaluated in several consecutive sorption-desorption cycles. Cadmium concentration of 0.005mg l−1, as a standard limit for potable water, was considered as the breakthrough concentration. The maximum column performance was achieved 81% at 7.5 cm bed length and flow rate of 15 ml min−1. Indeed, increasing the bed height increased the sorption performance and service time, while increasing the feed flow rate had a negative effect. Maximum sorption capacity value remained almost constant by the bed height changes; however, increase in the feed flow rate slightly decreased it. The modeling results revealed that the Yoon-Nelson model was more accurate than Thomas for describing the experimental breakthrough data, especially at low flow rates. Column service time predictions were surprisingly achieved using the Bed Depth Service Time model even at extrapolations. 20% reduction in column adsorption efficiency was observed at the end of four consecutive sorption-desorption cycles; however, desorption efficiencies were achieved more than 99% in each cycle.

Evaluation of the Effect of Pentoxifylline on Cisplatin-Induced Testicular Toxicity in Rats

Ali Reza Fallahzadeh,Zohreh Rezaei,Hamid Reza Rahimi,Mehrazd Jafari Barmak,Hossein Sadeghi,Sadrollah Mehrabi,Seyed Mohammadreza Rabani,Iraj Ragerdi Kashani,Vahid Barati,Reza Mahmoudi 한국독성학회 2017 Toxicological Research Vol.33 No.3

Chemotherapy is associated with male infertility. Cisplatin (cis-diamminedichloro-platinum (II) (CDDP) as a chemotherapy medication used to treat a number of cancers has been reported to most likely induce testicular toxicity. Administration of antioxidants, such as pentoxifylline (PTX) may reduce some Adverse Drug Reactions (ADRs) of CDDP. Therefore, this study investigated the potentially protective effects of PTX on CDDP-induced testicular toxicity in adult male rats. For this purpose, 42 male rats were randomly divided into 7 groups. The rats were orally pretreated with PTX at the 3 doses of 75, 150, and 300 mg/kg once a day for 14 successive days. On the 14<SUP>th</SUP> day of the study, they were intraperitoneally (IP) administered with a single dose of CDDP (7 mg/kg). Finally, the sperm/testis parameters, serum levels of reproductive hormones, including testosterone, Luteinizing Hormone (LH), and Follicle Stimulating Hormone (FSH) as the pivotal endocrine factors controlling testicular functions, and histopathological changes of testis tissue were examined. Pretreatment with the two doses of 75 and 150 mg/kg PTX indicated significant increases in the sperm count and motility induced by CDDP administration. The right and significantly left testis weights were decreased following the treatment with 300 mg/kg of PTX plus CDDP. However, 75 mg/kg of PTX plus CDDP showed the best near-to-normal histopathological features. The results demonstrated that PTX alone enhanced some parameters, such as the sperm count, while reducing other parameters, including sperm fast motility and germ layer thickness. Furthermore, despite testosterone or LH levels, the mean serum FSH level was significantly augmented by the doses of 75 and 150 mg/kg. It was concluded that PTX administration cannot reduce CDDP-induced testicular toxicity even at high doses (e.g., 300 mg/kg), while it seemed to partially intensify CDDP toxicity effects at a dose of 75 mg/kg. Thus, further research is required in this regard.

Evaluation of zinc finger E-box binding homeobox 1 and transforming growth factor-beta2 expression in bladder cancer tissue in comparison with healthy adjacent tissue

Ali Mahdavinezhad,Reza Yadegarazari,Seyed Habibollah Mousavi-Bahar,Jalal Poorolajal,Mohammad Jafari,Mohammad Ali Amirzargar,Hosein Effatpanah,Massoud Saidijam 대한비뇨의학회 2017 Investigative and Clinical Urology Vol.58 No.2

Purpose: The fifth most common cancer is allocated to bladder cancer (BC) worldwide. Understanding the molecular mechanisms of BC invasion and metastasis to identify target therapeutic strategies will improve disease survival. So the aim of this study was to measure expression rate of zinc finger E-box binding homeobox 1 (ZEB1) and transforming growth factor-beta2 (TGF-β2) mRNA in tissue samples of patients with BC and its healthy adjacent tissue samples and their association with muscle invasion, size and grade of the tumor. Materials and Methods: Tissue samples were collected from 35 newly diagnosed untreated patients with BC from 2013 to 2014. Total RNA was extracted from about 50-mg tissue samples using TRIzol reagent. TAKARA SYBR Premix EX Tag II was applied to determine the rate of mRNA expression by real-time polymerase chain reaction (PCR). To obtain final validation, PCR product of ZEB1 and TGF-β2 were sequenced. STATA 11 software was used to analyze the data. Results: The expression level of ZEB1 in tumor samples was significantly more than of in healthy adjacent tissue samples. Up-regulation of TGF-β2 showed a strong association with muscle invasion (p=0.017). There was also demonstrated a relationship between over expression of ZEB1 with the tumor size (p=0.050). Conclusions: It looks ZEB1 and TGF-β2 had a role in BC patients. In this study ZEB1 expression was higher in BC tissues than that of in healthy control tissues. There was demonstrated a markedly association between overexpression of TGF-β2 and muscle invasion. Therefore, they are supposed to be candidate as potential biomarkers for early detection and progression of BC.

Evaluation of the Effect of Pentoxifylline on Cisplatin-Induced Testicular Toxicity in Rats

Fallahzadeh, Ali Reza,Rezaei, Zohreh,Rahimi, Hamid Reza,Barmak, Mehrazd Jafari,Sadeghi, Hossein,Mehrabi, Sadrollah,Rabani, Seyed Mohammadreza,Kashani, Iraj Ragerdi,Barati, Vahid,Mahmoudi, Reza Korean Society of ToxicologyKorea Environmental Mu 2017 Toxicological Research Vol.33 No.3

Chemotherapy is associated with male infertility. Cisplatin (cis-diamminedichloro-platinum (II) (CDDP) as a chemotherapy medication used to treat a number of cancers has been reported to most likely induce testicular toxicity. Administration of antioxidants, such as pentoxifylline (PTX) may reduce some Adverse Drug Reactions (ADRs) of CDDP. Therefore, this study investigated the potentially protective effects of PTX on CDDP-induced testicular toxicity in adult male rats. For this purpose, 42 male rats were randomly divided into 7 groups. The rats were orally pretreated with PTX at the 3 doses of 75, 150, and 300 mg/kg once a day for 14 successive days. On the $14^{th}$ day of the study, they were intraperitoneally (IP) administered with a single dose of CDDP (7 mg/kg). Finally, the sperm/testis parameters, serum levels of reproductive hormones, including testosterone, Luteinizing Hormone (LH), and Follicle Stimulating Hormone (FSH) as the pivotal endocrine factors controlling testicular functions, and histopathological changes of testis tissue were examined. Pretreatment with the two doses of 75 and 150 mg/kg PTX indicated significant increases in the sperm count and motility induced by CDDP administration. The right and significantly left testis weights were decreased following the treatment with 300 mg/kg of PTX plus CDDP. However, 75 mg/kg of PTX plus CDDP showed the best near-to-normal histopathological features. The results demonstrated that PTX alone enhanced some parameters, such as the sperm count, while reducing other parameters, including sperm fast motility and germ layer thickness. Furthermore, despite testosterone or LH levels, the mean serum FSH level was significantly augmented by the doses of 75 and 150 mg/kg. It was concluded that PTX administration cannot reduce CDDP-induced testicular toxicity even at high doses (e.g., 300 mg/kg), while it seemed to partially intensify CDDP toxicity effects at a dose of 75 mg/kg. Thus, further research is required in this regard.

New laboratory techniques (novel) in making organic-mineral mulch to control wind and water erosion and its use in global scale

Shojaei Saeed,Ardakani Mohammad Ali Hakimzadeh,Sodaiezadeh Hamid,Jafari Mohammad,Afzali Seyed Fakhreddin 대한공간정보학회 2021 Spatial Information Research Vol.29 No.1

In recent decades, wind erosion is increasing across the world as a result of climate change and drought. Therefore, in this study we aim to make mulch with new formulation in order to control wind and water erosion. The materials have been chosen based on their efficiency, availability, and cheapness. Also, cement, gypsum, lime, and blackstrap mixture were selected to make organicmineral mulch. Moreover, we applied response surface method to design and optimize the conditions of the experiment. In this study, we applied central composite design using 10–50 g of gypsum, 12.5–62.5 g of lime, 2.5–12.5 g of blackstrap, and 2.5–12.5 g of cement. The results showed that as all materials cause an increase in the resistance of soil as they are used more, and ultimately they lead to a decrease in erosion except for gypsum which has opposite reaction in high density. Furthermore, in order to reach the minimum wind erosion, a mixture of cement 6.43 g, blackstrap 9.25 g, gypsum 37.26 g, lime 48.92 g was suggested by design-expert software. Based on this experiment, the lowest minimum amount of water erosion was obtained when 5.86 g of blackstrap, 5.13 g of cement, 31.65 g of gypsum, and 46.83 g of lime were applied in the mixture. Analysis of variance showed that data simulation and comparison with real data are highly accurate. (90% accurate) Therefore, the formulation in this study has enough standards to be utilized to control erosion in many regions in the world.

Thermorheological Complexity of a Dynamically Asymmetric Miscible Blend: The Improving Role of Na+-MMT Nanoclay

Mahdi Ghelichi,Nader Taheri Qazvini,Seyed Hassan Jafari,Hossein Ali Khonakdar 한국고분자학회 2013 Macromolecular Research Vol.21 No.4

The influence for the minor amount of sodium montmorillonite (Na+-MMT) nanoclay on the thermorheological complexity of a miscible blend of 20 wt% poly(ethylene oxide) (PEO) in poly(methyl methacrylate)(PMMA) is studied. The dispersion of Na+-MMT in the PEO/PMMA is assessed via X-ray diffraction. The empirical principle of time-temperature superposition is found to be partially restored in the case of blend nanocomposite,whereas it fails for the neat PEO/PMMA blend. The relaxation times of each component are determined from the oscillatory shear rheometry data in the form of a monomeric friction coefficient. The chain dynamics of components is coupled in the presence of hydrophilic nanoclay, which preferentially adsorbs PEO. The self-concentration model of Lodge and McLeish successfully describes the temperature dependence of the PMMA monomeric friction coefficient in both the neat and blend nanocomposite in regards to the temperature range studied.