scispace - formally typeset
Search or ask a question
Author

Mohammad Sirousazar

Bio: Mohammad Sirousazar is an academic researcher from Urmia University of Technology. The author has contributed to research in topics: Polyvinyl alcohol & Self-healing hydrogels. The author has an hindex of 18, co-authored 53 publications receiving 1250 citations. Previous affiliations of Mohammad Sirousazar include University of Mohaghegh Ardabili & Tarbiat Modares University.


Papers
More filters
Journal ArticleDOI
TL;DR: In this article, the effect of organoclay quantity on the structural, swelling, physical and mechanical properties of nanocomposite hydrogel wound dressing was investigated and the results showed that the nanocomposition hydrogels could meet the essential requirements for the reasonable wound dressing with some desirable characteristics such as relatively good swelling, appreciated vapour transmission rate, excellent barrierity against microbe penetration and mechanical property.

565 citations

Journal ArticleDOI
TL;DR: In this paper, an account of the experiments on grafting polyacrylamide onto organophilic montmorillonite was given. Butts et al. showed that only the silanol groups on the edge of the clay react with vinyltrichlorosilane.

88 citations

Journal ArticleDOI
TL;DR: In this article, a new configuration of ejectorexpansion transcritical CO2 (TRCC) refrigeration cycle is presented, which uses an internal heat exchanger and intercooler to enhance the performance of the new cycle.
Abstract: In this paper, a new configuration of ejector-expansion transcritical CO2 (TRCC) refrigeration cycle is presented, which uses an internal heat exchanger and intercooler to enhance the performance of the new cycle. The theoretical analysis on the performance characteristics was carried out for the new cycle based on the first and second laws of thermodynamics. It was found that, compared with the conventional transcritical CO2 cycle and ejector-expansion transcritical CO2 cycle, the simulation results show that the coefficient of performance and second law efficiency of the new cycle were increased by about 55.5 and 26%, respectively, under the operating conditions that evaporator temperature is 10°C, gas cooler outlet temperature is 40°C and gas cooler pressure is optimum pressure. It is also concluded that the entrainment ratio for the new ejector-expansion TRCC cycle is on average 35% higher than that of the conventional ejector-expansion TRCC cycle. The analysis results are of significance to provide theoretical basis for design optimization of the transcritical CO2 refrigeration cycle with an ejector-expansion device, internal heat exchanger and intercooler. Copyright © 2007 John Wiley & Sons, Ltd.

66 citations

Journal ArticleDOI
TL;DR: A series of nanocomposite hydrogels based on polyvinyl alcohol containing 0-10 wt % of the organically modified montmorillonite clay were prepared by freezing-thawing cyclic method as discussed by the authors.
Abstract: A series of nanocomposite hydrogels based on polyvinyl alcohol containing 0–10 wt % of the organically modified montmorillonite clay were prepared by freezing-thawing cyclic method. The morphology of the nanocomposite hydrogels was observed by the scanning electron microscopy technique. The structural properties were determined by measuring the network mesh size, crosslinking density, and average molecular weight of polymer chains between crosslinks. The swelling behavior and the effect of swelling medium temperature on the swelling kinetics and characteristics of the nanocomposite hydrogels were also investigated. The results showed that two structural characteristics i.e., network mesh size and average molecular weight of polymer chains between crosslinks have inverse dependence on the clay loading level in the nanocomposite hydrogel, while crosslinking density shows completely direct dependence. Swelling measurements demonstrated a linear relation between the degree of swelling and the square root of immersion time at all swelling medium temperatures. The results indicated that the swelling characteristics of the nanocomposite hydrogels including the equilibrium degree of weight and volume swelling and the equilibrium water content were decreased by increasing the quantity of the clay incorporated into the hydrogel as well as by decreasing the temperature of swelling medium. While, the time required to reach to the equilibrium condition, as another swelling characteristic of the hydrogels, exhibited a completely opposite behavior. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.

61 citations

Journal ArticleDOI
TL;DR: It is shown that the prepared nanocomposite hydrogel is non-toxic and can be used as a biocompatible wound dressing in practical wound management.
Abstract: In the present work, a nanocomposite hydrogel wound dressing was prepared on the basis of poly(vinyl alcohol) using organically-modified montmorillonite as nanoclay by the freezing–thawing cyclic method. In vivo assays were performed to evaluate its performance as an applicable wound dressing on animals. It showed an improved healing process for wounds covered by the prepared nanocomposite hydrogel compared with control wounds covered by sterile gauze. Significant improvements, such as better creation of moist surfaces on the wound with less scar formation, shorter duration of healing operation and better closing of the wound edges with enhanced tensile properties of the healed wound, i.e., tensile strength and elongation-at-break, were observed using the prepared nanocomposite hydrogel in comparison to the sterile gauze. An in vitro cytotoxic assay was also utilized to determine the biocompatibility of the prepared nanocomposite hydrogel. It showed that the prepared nanocomposite hydrogel is non-toxic an...

48 citations


Cited by
More filters
Journal ArticleDOI
TL;DR: In this article, the authors present the past and current efforts with a brief description on the featured properties of hydrogel membranes fabricated from biopolymers and synthetic ones for wound dressing applications.

1,059 citations

Journal ArticleDOI
TL;DR: The development of advanced hydrogel with tunable physiochemical properties is highlighted, with particular emphasis on elastomeric, light‐sensitive, composite, and shape‐memory hydrogels, and a number of potential applications and challenges in the utilization in regenerative medicine are reviewed.
Abstract: Hydrogels are hydrophilic polymer-based materials with high water content and physical characteristics that resemble the native extracellular matrix. Because of their remarkable properties, hydrogel systems are used for a wide range of biomedical applications, such as three-dimensional (3D) matrices for tissue engineering, drug-delivery vehicles, composite biomaterials, and as injectable fillers in minimally invasive surgeries. In addition, the rational design of hydrogels with controlled physical and biological properties can be used to modulate cellular functionality and tissue morphogenesis. Here, the development of advanced hydrogels with tunable physiochemical properties is highlighted, with particular emphasis on elastomeric, light-sensitive, composite, and shape-memory hydrogels. Emerging technologies developed over the past decade to control hydrogel architecture are also discussed and a number of potential applications and challenges in the utilization of hydrogels in regenerative medicine are reviewed. It is anticipated that the continued development of sophisticated hydrogels will result in clinical applications that will improve patient care and quality of life.

1,043 citations

Journal ArticleDOI
TL;DR: In this article, an overview of different types of wounds, effective parameters in wound healing and different wound dressing materials with a special emphasis paid to those prepared by electrospinning is presented.
Abstract: Wound dressings have experienced continuous and significant changes since the ancient times. The development starts with the use of natural materials to simply cover the wounds to the materials of the present time that could be specially made to exhibit various extraordinary functions. The modern bandage materials made of electrospun biopolymers contain various active compounds that are beneficial to the healing of wounds. These materials are fibrous in nature, with the size of fibers segments ranging from tens of nanometers to micrometers. With the right choices of biopolymers used for these fibrous materials, they could enhance the healing of wounds significantly compared with the conventional fibrous dressing materials, such as gauze. These bandages could be made such that they contain bioactive ingredients, such as antimicrobial, antibacterial, and anti-inflammatory agents, which could be released to the wounds enhancing their healing. In an active wound dressing (AWD), the main purpose is to control the biochemical states of a wound in order to aid its healing process. This review provides an overview of different types of wounds, effective parameters in wound healing and different types of wound dressing materials with a special emphasis paid to those prepared by electrospinning. Copyright © 2009 John Wiley & Sons, Ltd.

778 citations

Journal ArticleDOI
TL;DR: In this paper, the authors provide an update on recent developments in heat pump systems, and is intended to be a "one-stop" archive of known practical heat pump solutions.

737 citations