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Experimental Study of the Effects of Compaction Water Content on Dynamic Properties of Babolsar Sand under Anisotropic Loading
, M.Sc. Thesis Sharif University of Technology ; Jafarzadeh, Fardin (Supervisor)
Abstract
In many of the geotechnical engineering projects, such as construction of embankments and roads, soil is compacted with different water contents. Difference in compaction water content leads to different dynamic behaviors under cyclic loadings like earthquake and traffic. On the other hand, the magnitude and the direction of principal stresses on soil element, affect the dynamic response of the soil. The main objective of this research is to study the effects of compaction water content on dynamic properties of soil in anisotropic loading conditions. Therefore, the dynamic parameters of Babolsar sand, including shear strain amplitude, shear modulus and damping ratio under induced anisotropic...
Processing and properties of nanofibrous bacterial cellulose-containing polymer composites: a review of recent advances for biomedical applications
, Article Polymer Reviews ; Volume 60, Issue 1 , 2020 , Pages 144-170 ; Mahmoodi, A ; Mahmoudi, N ; Zandi, N ; Simchi, A ; Sharif University of Technology
Taylor and Francis Inc
2020
Abstract
Bacterial cellulose (BC) is an extracellular natural polymer produced by many microorganisms and its properties could be tailored via specific fabrication methods and culture conditions. There is a growing interest in BC derived materials due to the main features of BC such as porous fibrous structure, high crystallinity, impressive physico-mechanical properties, and high water content. However, pristine BC lacks some features, limiting its practical use in varied applications. Thus, fabrication of BC composites has been attempted to overcome these constraints. This review article overviews most recent advance in the development of BC composites and their potential in biomedicine including...
Stereolithography 3D bioprinting method for fabrication of human corneal stroma equivalent
, Article Annals of Biomedical Engineering ; Volume 48, Issue 7 , June , 2020 , Pages 1955-1970 ; Abdekhodaie, M. J ; Kumar, H ; Mashayekhan, S ; Baradaran Rafii, A ; Kim, K ; Sharif University of Technology
Springer
2020
Abstract
Abstract: 3D bioprinting technology is a promising approach for corneal stromal tissue regeneration. In this study, gelatin methacrylate (GelMA) mixed with corneal stromal cells was used as a bioink. The visible light-based stereolithography (SLA) 3D bioprinting method was utilized to print the anatomically similar dome-shaped structure of the human corneal stroma. Two different concentrations of GelMA macromer (7.5 and 12.5%) were tested for corneal stroma bioprinting. Due to high macromer concentrations, 12.5% GelMA was stiffer than 7.5% GelMA, which made it easier to handle. In terms of water content and optical transmittance of the bioprinted scaffolds, we observed that scaffold with...
Prediction of CO2 equilibrium moisture content using least squares support vector machines algorithm
, Article Petroleum and Coal ; Volume 58, Issue 1 , 2016 , Pages 27-46 ; 13377027 (ISSN) ; Abdi, J ; Bahadori, M ; Lee, M ; Bahadori, A ; Sharif University of Technology
Slovnaft VURUP a.s
2016
Abstract
The burning of fossil fuels such as gasoline, coal, oil, natural gas in combustion reactions results in the production of carbon dioxide. The phase behavior of the carbon dioxide + water system is complex topic. Unlike methane, CO2 exhibits a minimum in the water content. These minima cannot be predicted by existing methods accurately. In this communication, two mathematical-based procedures have been proposed for accurate computation of CO2 water content for tempe-ratures between 273.15 and 348.15 K and the pressure range between 0.5 and 21 MPa. The first is based on least squares support vector machine (LSSVM) algorithm and the second applies multilayer perceptron (MLP) artificial neural...
Optimizing temperature and introducing new process arrangements for elevating clay's longevity based on the known poisons in the separation process of trace olefins from aromatics
, Article Journal of Chemical Technology and Biotechnology ; Volume 97, Issue 4 , 2022 , Pages 973-983 ; 02682575 (ISSN) ; Farhadi, F ; Akbari Kenari, M ; Ramakrishna, S ; Sharif University of Technology
John Wiley and Sons Ltd
2022
Abstract
BACKGROUND: The clay treatment widely utilized to reduce unsaturated components in aromatic stream has a detrimental effect on catalyst lifetime. Due to the short lifetime of commercial clay, a huge number of studies have been carried out to address this problem over the last decade. This study aims to optimize the temperature for longer serviceability of clay by removal of unsaturated aliphatic components from aromatic streams through the adsorption and catalytic properties of clay. A novel process arrangement is introduced by scheduling the reuse of deactivated clay that is discarded after deactivation. RESULTS: Results showed that the suitable range of temperature for olefin removal is...
Comparison of using formaldehyde and carboxy methyl chitosan in preparation of Fe3O4 superparamagnetic nanoparticles-chitosan hydrogel network: Sorption behavior toward bovine serum albumin
, Article Process Safety and Environmental Protection ; Volume 102 , 2016 , Pages 119-128 ; 09575820 (ISSN) ; Hanifpour, F ; Taheri, R ; Javadian, H ; Ghasemi, M ; Sharif University of Technology
Institution of Chemical Engineers
Abstract
A novel and cost effective method of bio-separation developed recently is magnetic separation technology. In this study, super paramagnetic Fe3O4 nanoparticles are used for separation of bovine serum albumin (BSA) protein from plasma/serum samples at optimized conditions. The synthesis of chitosan hydrogel networks by two variant approaches that involve (1) crosslinking of chitosan with formaldehyde and (2) formation of carboxy methyl chitosan mediated complex, was investigated and the percent of gelation, swelling ratio and equilibrium water content were calculated. The results revealed the formation of better quality hydrogel from the first approach. In step 1, to quantify the BSA...
Evaluation of SMAP/Sentinel 1 high-resolution soil moisture data to detect irrigation over agricultural domain
, Article IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing ; Volume 14 , 2021 , Pages 10733-10747 ; 19391404 (ISSN) ; Abolafia Rosenzweig, R ; Tajrishy, M ; Das, N ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2021
Abstract
Irrigation is not well represented in land surface, hydrological, and climate models. One way to account for irrigation is by assimilating satellite soil moisture data that contains irrigation signal with land surface models. In this study, the irrigation detection ability of SMAP enhanced 9 km and SMAP-Sentinel 1 (SMAP-S1), 3 km and 1 km soil moisture products are evaluated using the first moment (mean) and the second moment (variability) of soil moisture data. The SMAP enhanced 9 km soil moisture product lacks irrigation signals in an irrigated plain south of Urmia Lake, whereas SMAP-S1 products record irrigation signal in soil moisture variability. Despite observing higher variability...
The role of co-solvents in improving the direct transesterification of wet microalgal biomass under supercritical condition
, Article Bioresource Technology ; Volume 193 , October , 2015 , Pages 90-96 ; 09608524 (ISSN) ; Vossoughi, M ; Pazuki, G ; Sharif University of Technology
Elsevier Ltd
2015
Abstract
In this research, direct conversion of wet algal biomass into biodiesel using supercritical methanol was studied. In this process, microalgal lipids simultaneously was extracted and converted to biodiesel under high pressure and temperature conditions without using any catalyst. Several experiments have been performed to optimize the methanol amount and it has been revealed that the best performance was achieved by using methanol/wet biomass ratio of 8:1. The effect of using various co-solvents in increasing the efficiency of the supercritical process was investigated. It has been shown that hexane was the most effective co-solvent and its optimal ratio respect to wet biomass was 6:1. The...
Combination of water head control and axis translation techniques in new unsaturated cyclic simple shear tests
, Article Soil Dynamics and Earthquake Engineering ; Volume 126 , 2019 ; 02677261 (ISSN) ; Jafarzadeh, F ; Sadeghi, H ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
A cyclic simple shear device was modified for testing coarse-grained soils at unsaturated conditions. A combined methodology of controlling suction for the practical range of coarse-grained soil water retention curves was adopted. Water head control method was used to accurately control suction within capillary and transition zones of such soils. The axis translation technique, on the other hand, was employed as a complementary approach to reach higher suction values within residual zone. In order to evaluate the performance of the new setup, independent cyclic tests were carried out at various initial suctions including all key points and zones along the primary drying path. The analyses of...
Enzymatically crosslinked hyaluronic acid microgels as a vehicle for sustained delivery of cationic proteins
, Article European Polymer Journal ; Volume 115 , 2019 , Pages 234-243 ; 00143057 (ISSN) ; Abdekhodaie, M. J ; Mousavi, A ; Zoetebier, B ; Dijkstra, P. J ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
In this study, a novel biodegradable hyaluronic acid (HA) based microgel were prepared via enzymatic crosslinking of tyramine conjugated HA (HA-TA) in an inverse microemulsion. HA-TA microdroplets were crosslinked within a few seconds in the presence of horseradish peroxidase (HRP) and hydrogen peroxide (H 2 O 2 ). The high water content of the polymeric network and the inherent negative charge of the HA-TA microgels provided a suitable platform for encapsulation of cationic proteins like lysozyme and TGF-β1 growth factor. The results demonstrated that lysozyme was released, after an initial burst release, in a suitable sustained manner over a period of four weeks. Both diffusion and...
Magnetic, thermally stable, and superhydrophobic polyurethane sponge: A high efficient adsorbent for separation of the marine oil spill pollution
, Article Chemosphere ; Volume 287 , 2022 ; 00456535 (ISSN) ; Pourjavadi, A ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Herein, we demonstrated a facile method for the fabrication of magnetic and superhydrophobic polyurethane sponge with water contact angle of 159° as an adsorbent for cleanup the marine oil spill pollution. For this aim, a polyurethane sponge was coated with carbon black (CB), hexagonal boron nitride (h-BN)@Fe3O4, and acrylic resin and then characterized by different techniques. Owing to the chemical and thermal stability of h-BN and CB, the modified sponge was stable under corrosive conditions (pH = 1–14 and salt solutions) and at different temperatures (−12 °C–105 °C). In addition to common oils and organic solvents, we also used the real spilled oils containing monoaromatics and...
An improved Kalman filtering approach for the estimation of unsaturated flow parameters by assimilating photographic imaging data
, Article Journal of Hydrology ; Volume 590 , 2020 ; Belfort, B ; Lehmann, F ; Weill, S ; Ataie Ashtiani, B ; Fahs, M ; Sharif University of Technology
Elsevier B.V
2020
Abstract
As a non-invasive method, photographic imaging techniques offer some interesting potentials for characterization of soil moisture content in unsaturated porous media, enabling mapping at very fine resolutions in both space and time. Although less explored, the wealth of soil moisture data provided by photographic imaging is also appealing for the estimation of unsaturated soil hydraulic parameters through inverse modeling. However, imaging data have some unique characteristics, including high susceptibility to noise, which can negatively affect the parameter estimation process. In this study a sequential data assimilation approach is developed to simultaneously update soil moisture content...
Applying ultrasonic fields to separate water contained in medium-gravity crude oil emulsions and determining crude oil adhesion coefficients
, Article Ultrasonics Sonochemistry ; Volume 70 , 2021 ; 13504177 (ISSN) ; Wood, D. A ; Jokar, S. M ; Rahimpour, M. R ; Sharif University of Technology
Elsevier B.V
2021
Abstract
Separating produced water is a key part of production processing for most crude oils. It is required for quality reasons, and to avoid unnecessary transportation costs and prevent pipework corrosion rates caused by soluble salts present in the water. A complicating factor is that water is often present in crude oil in the form of emulsions. Experiments were performed to evaluate the performance of ultrasonic fields in demulsifying crude oil emulsions using novel pipe-form equipment. A horn-type piezoelectric ultrasonic transducer with a frequency of 20 kHz and power ranging from 80 W to 1000 W was used for experimental purposes. The influences of the intensity of ultrasonic fields,...
Green products from herbal medicine wastes by subcritical water treatment
, Article Journal of Hazardous Materials ; Volume 424 , 2022 ; 03043894 (ISSN) ; Tavakoli, O ; Sarkhanpour, R ; Sajadi, S. M ; Zarrintaj, P ; Rabiee, N ; Akhavan, O ; Lima, E. C ; Saeb, M. R ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Herbal medicine wastes (HMWs) are byproducts of medicine factories, which are mainly landfilled for their environmental problems. Only bearing in mind the contamination and concerns caused by the COVID-19 pandemic and environmental emissions, the worth of herbal medicine wastes management and conversion to green products can be understood. In this work, subcritical water treatment was carried out batch-wise in a stainless tube reactor in the pressure range of 0.792–30.0 MPa, varying the temperature (127–327 °C) and time (1–60 min) of extraction. This resulted in new and green material sources, including organic acids, amino acids, and sugars. Amazingly, at very low extraction times (below 5...
Poly (vinyl alcohol)/nano-diamond composite films and hydrogels prepared by gamma ray
, Article Journal of Polymer Engineering ; Volume 38, Issue 9 , 2018 , Pages 857-862 ; 03346447 (ISSN) ; Dadbin, S ; Haddadi, S ; Sharif University of Technology
De Gruyter
2018
Abstract
Poly (vinyl alcohol) and nano-diamond, PVA/ND, hydrogels were prepared and assessed as prosthetic material suitable for replacement of the nucleus pulposus. The hydrogels were prepared by gamma irradiation at various doses (15 kGy, 25 kGy, 35 kGy, 45 kGy) and at various ND concentrations ranging from 0.25 wt.% to 3 wt.%. Extent of gelation, equilibrium water content, and viscoelastic properties of swelled hydrogels at definite water contents were measured and examined as a function of ND concentration as well as gamma dose. According to viscoelastic measurements, the strength of hydrogels increased considerably over that of pure PVA at a low concentration of ND. By increasing irradiation...
Nano-magnetic poly (vinyl alcohol) hydrogels
, Article Advanced Materials Research ; Volume 829 , 2014 , Pages 539-543 ; ISSN: 10226680 ; ISBN: 9783037859070 ; Frounchi, M ; Dadbin, S ; Sharif University of Technology
Abstract
Surface modified magnetic nanoparticles (M-NPs) were synthetized and stabilized in poly (vinylalcohol) solution. The solutions with various magnetic nanoparticles contents were gammairradiated and magnetic poly (vinyl-alcohol) (M-PVA) hydrogels were synthesized. The magnetic hydrogels and also the un-irradiated magnetic poly (vinyl alcohol) nanocomposite films were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), Fourier transform infrared spectroscopy (FTIR) and mechanical measurement. The M-NPs were uniformly dispersed in the polymer matrix due to a strong interaction between the surface-modified M-NPs and polymer matrix....
Characterization of the effect of disturbance on the hydro-mechanical behavior of a highly collapsible loessial soil
, Article Unsaturated Soils: Research and Applications - Proceedings of the 6th International Conference on Unsaturated Soils, UNSAT 2014 ; Vol. 1, issue , 2014 , p. 261-266 ; Khosravi, A ; Ghaizadeh, S ; Garakani, A. A ; Meehan, C. L ; Sharif University of Technology
Abstract
Highly collapsible loessial soils are characterized by an open void structure that can experience significant settlement upon loading. In the field, these partially saturated Aeolian deposits are particularly susceptible to wetting-induced collapse. Due to difficulties in preparing undisturbed specimens from highly collapsible soils, previous studies have generally performed laboratory tests on reconstituted specimens with different water contents and densities, and the effect of disturbance on the initial state of the soil was ignored. Disturbance in highly collapsible soil specimens may significantly affect the natural composition of the soil matrix, the non-homogeneous distribution of...
Disc size markedly influences concentration profiles of intravenously administered solutes in the intervertebral disc: A computational study on glucosamine as a model solute
, Article European Spine Journal ; Vol. 23, issue. 4 , April , 2014 , p. 715-723 ; Shirazi-Adl, A ; Parnianpour, M ; Urban, J. P. G ; Sharif University of Technology
Abstract
Purpose: Tests on animals of different species with large differences in intervertebral disc size are commonly used to investigate the therapeutic efficacy of intravenously injected solutes in the disc. We hypothesize that disc size markedly affects outcome. Methods: Here, using a small non-metabolized molecule, glucosamine (GL) as a model solute, we calculate the influence of disc size on transport of GL into rat, rabbit, dog and human discs for 10 h post intravenous-injection. We used transient finite element models and considered an identical GL supply for all animals. Results: Huge effects of disc size on GL concentration profiles were found. Post-injection GL concentration in the rat...
Experimental investigation of rheological and morphological properties of water in crude oil emulsions stabilized by a lipophilic surfactant
, Article Journal of Dispersion Science and Technology ; Volume 34, Issue 3 , Feb , 2013 , Pages 356-368 ; 01932691 (ISSN) ; Ramazani, S. A. A ; Taghikhani, V ; Ghotbi, C ; Sharif University of Technology
2013
Abstract
Rheological behavior of two crude oils and their surfactant-stabilized emulsions with initial droplet sizes ranging from 0.5 to 75 μm were investigated at various temperatures under steady and dynamic shear testing conditions. In order to evaluate the morphology and Stability of emulsions, microscopic analysis was carried out over three months and average diameter and size distribution of dispersed droplets were determined. The water content and surfactant concentration ranged from 10 to 60% vol/vol and 0.1 to 10% wt/vol, respectively. The results indicated that the rheological properties and the physical structure and stability of emulsions were significantly influenced by the water content...
High temperature synthesis of SAPO-34: applying an L9 taguchi orthogonal design to investigate the effects of experimental parameters
, Article Powder Technology ; Volume 217 , February , 2012 , Pages 223-230 ; 00325910 (ISSN) ; Kazemian, H ; Soltanieh, M ; Hosseinpour, M ; Rohani, S ; Sharif University of Technology
Abstract
SAPO-34 zeolite-like particles were successfully synthesized at high temperature environment. An L9 orthogonal array of the Taguchi method was implemented to investigate the effects of experimental conditions to prepare SAPO-34 with respect to crystallinity of the final product phase. The results showed that the favorable phase crystallinity was improved by increasing the hydrothermal synthesis temperature and organic template content, whereas increasing the water content in synthesis mixture decreased the crystallinity. No significant changes in crystallinity of the final products were observed by increasing the synthesis duration. In addition, zeolite SAPO-5, which was formed as the...