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Open Access Article
1 - Investigation on the physical and morphological properties of the biocomposite manufactured by mixing treated OCC pulp fibers and polypropylene with various molecular weights
Mohammadreza Amiri margavi Mohammad Talaeipour AmirHooman Hemmasi Hemmasi Behzad Bazyar Ismaeil GhasemiIn this study, the effect of the chemical treatment of OCC pulp and polypropylene molecular weight on the physical and morphological properties of cellulosic biocomposite was studied. For this purpose, OCC fibers were treated with acetic anhydride and then mixed with po MoreIn this study, the effect of the chemical treatment of OCC pulp and polypropylene molecular weight on the physical and morphological properties of cellulosic biocomposite was studied. For this purpose, OCC fibers were treated with acetic anhydride and then mixed with polypropylene and the compatibilizing agent (0 and 3%). The ratio of fibers and polymer materials was considered 30 to 70, which was manufactured by the hot-pressing method at 180 °C. The ratio of fibers and polymer materials was considered 30 to 70, which was manufactured by the hot-pressing method at 180 °C. The water absorption, volumetric swelling, and contact angle were measured on each sample according to the ASTM standards. Fourier transform spectroscopy (FTIR) and scanning electron microscopy (SEM) were used to investigate the chemical modification of fibers and the morphology of biocomposites, respectively. The results of the measurements showed that the effect of chemical treatment and polypropylene on contact angle and water absorption was significant and chemical modification of the fibers reduced the water absorption and volumetric swelling. Finally, FTIR analysis showed that hydroxyl groups were decreased and the SEM images indicated the bond between fibers and polypropylene was improved through chemical modification of OCC fibers. Manuscript profile -
Open Access Article
2 - Evaluation of healing effect of clove nanofibers in comparison with poly-caprolactone nanofibers in experimental skin wounds
M. Ashjazadeh, A. Jahandideh, G. Abedi, A. Akbarzadeh, S. Hesaraki,To date, the anti-inflammatory and antimicrobial effect of clove extract has been proven, which makes it one of the treatments that can be used in wound healing. Comparing the healing effect with other healing aids makes clove extract stand out among wound healers. In t MoreTo date, the anti-inflammatory and antimicrobial effect of clove extract has been proven, which makes it one of the treatments that can be used in wound healing. Comparing the healing effect with other healing aids makes clove extract stand out among wound healers. In this study, histopathological examination of clove nanofibers (eugenol) was performed in comparison with polycaprolactone nanofibers in other experimental thicknesses created in rat skin. In 45 adult Wistar rats, a dorsal ulcer induced. They are then randomly divided into three groups of 15 (observed group, eugenol nanofibers and polycaprolactone), then each into five other groups of 5 (fraternity sample groups on days seven, 14, and 21) Divide, collagen, epithelial thickness, scar, leukocytes infiltration, edema, acute hemorrhage and stretch test were evaluated. In the eugenol treatment group, epithelialization and collagen index increased significantly (P <0.05) from days 7 to 21 from the other two budget groups. The results show that clove nanofibers accelerated the healing process in thickened skin function compared to polycaprolactone and the control group. Manuscript profile -
Open Access Article
3 - Comparison of Fracture Strength in Endodontically Treated Teeth Restored with Bulk fill, Bulk Fill Flowable and Conventional Composite with or without Using Ribbon Fibers
Amin Seidy Parvin Mirzakouchaki Leila Pishevar -
Open Access Article
4 - Vibration Analysis of a Magneto Thermo Electrical Nano Fiber Reinforced with Graphene Oxide Powder Under Refined Beam Model
R Selvamani J Rexy F Ebrahimi -
Open Access Article
5 - Thermal and Mechanical Properties of Hybrid Composite Strengthened by Carbon Fibers/Aramid Fibers
F Basati M.H Yas -
Open Access Article
6 - A New Numerical Procedure for Determination of Effective Elastic Constants in Unidirectional Composite Plates
S Daryazadeh L Lvov Gennadiy M Tajdari -
Open Access Article
7 - Normal and Parallel Permeability of Preform Composite Materials used in Liquid Molding Processes: Analytical Solution
M Nazari M.M Shahmardan M Khaksar M Khatib S Mosayebi -
Open Access Article
8 - The Effect of Fiber Breakage on Transient Stress Distribution in a Single-Lap Joint Composite Material
M Shishehsaz S Yaghoubi -
Open Access Article
9 - Investigation on the effect of FMBO nanoparticles on the structure and morphology of composite nanofibers PVDF/FMBO
parisa aliahmadipoor rasool jamshidi gohari Dadkhoda GhazanfariRecent research has shown that long, porous nanofibers are one of the safest nanomaterials due to their controllable production, high specific surface area and continuous matrix structure. In this study, following the previous study of the authors, Structural phases of MoreRecent research has shown that long, porous nanofibers are one of the safest nanomaterials due to their controllable production, high specific surface area and continuous matrix structure. In this study, following the previous study of the authors, Structural phases of nanofibers were synthesized from combination of polyvinylidene fluoride (PVDF) and iron/manganese binary oxide nanoparticles (FMBO) were evaluated. Mineral adsorbents were integrated into polymer matrix in the range of zero to 0.5. The properties of nanofibers according to the structure and surface characteristics using SEM and TEM were determined. In this study, structural phases of PVDF and PVDF/FMBO electrospinning nanofibers were distinguished by examining the FTIR vibration bands and analyzing the XRD characteristics due to the different reports on the analysis of α, β and γ phases according to the measured data. The results of FTIR, specifically by examining bands 762 and 612, 1275 and 1234 cm-1 and its compliance with XRD results and reviewing published research the α, β and γ phases were distinguished, respectively. Manuscript profile -
Open Access Article
10 - Green Synthesis of Biocompatible Nanocomposite Containing Iron Oxide Using the Extract of the Artemisia Plant and Its Application in the Removal of Organophosphorus Toxins from Agricultural Waters
Roya Behrooz Nahid Rastakhiz Dadkhoda Ghazanfari Enayatollah Sheikhhosseini Sayed Ali AhmadiToday, the widespread use of organophosphorus insecticides such as chlorpyrifos in agriculture has caused serious environmental problems, and it seems necessary to provide a solution to eliminating these substances. Iron oxide nanoparticles are one of the types of nanop MoreToday, the widespread use of organophosphorus insecticides such as chlorpyrifos in agriculture has caused serious environmental problems, and it seems necessary to provide a solution to eliminating these substances. Iron oxide nanoparticles are one of the types of nanoparticles that are widely used in the environment due to their good magnetic properties and ability to absorb pollutants. Nanoparticles are prepared in different ways. Recently, the use of green synthesis methods of nanoparticles using plant extracts has attracted the attention of researchers due to its compatibility with the environment. In this research project, the green synthesis of iron oxide nanoparticles in the matrix of polylactic acid nanofibers was prepared with the plant extract of Artemisia as an effective and cheap super absorbent for agricultural water treatment. Then, the effect of this adsorbent in the removal of chlorpyrifos poison and the effect of variables affecting absorption such as contact time, amount of adsorbent, temperature and pH in this process were investigated. Analysis of the structure of the composition showed that iron oxide nanoparticles are well stabilized in polylactic acid nanofibers and the average size of nanoparticles is 29 nanometers. Also, the results of the absorption test by nano adsorbent showed that the maximum amount of absorption to remove chlorpyrifos is done at pH=7 and with an amount of 0.7 grams of adsorbent, and the prepared adsorbent can be reused after 5 times of recycling. Therefore, it can be concluded that due to the presence of iron oxide nanoparticles, the nanocomposite made can increase the absorption capacity of agricultural toxins. Manuscript profile -
Open Access Article
11 - فرآیند تقویت فیلتر تصفیه آب خانگی با نانو ذرات گیاهی
محبوبه شادابی بجند مهداد انکاری استفاده از نانو به عنوان کاهش دهنده آلاینده‎های آب آشامیدنی، به عنوان یکی از راه‎کارهای مدیریتی مطرح گردیده است. یکی از موارد این فناوری در ارتباط با کیفیت آب شرب می‎باشد. از این رو هدف از ارائه این پژوهش استفاده از نانو ذرات گیاهی (گیاه آ More استفاده از نانو به عنوان کاهش دهنده آلاینده‎های آب آشامیدنی، به عنوان یکی از راه‎کارهای مدیریتی مطرح گردیده است. یکی از موارد این فناوری در ارتباط با کیفیت آب شرب می‎باشد. از این رو هدف از ارائه این پژوهش استفاده از نانو ذرات گیاهی (گیاه آلوئه‎ورا) برای تقویت کردن فیلتر تصفیه‎های آب خانگی از جنس الیاف پلی‎پروپیلن است. طی تجزیه و تحلیل بدست آمده بر روی گیاه آلوئه‎ورا به عنوان تقویت کننده فیلتر، نتایج نشان داد که از پارامترهای مرتبط با فیلتر تصفیه آب خانگی که این فیلتر از لحاظ میزان جرم و ضخامت الیاف پلی‎پروپیلنی تقویت شده و میزان فشار حباب، قطر روزنه و قطر میانگین روزنه دارای ضخامت شاخص‎های درونی مناسب می‎باشد. همچنین مقادیر پارامترهای کیفی ( نیترات، نیتریت، سولفات، کلراید، فلوراید، سدیم، پتاسیم، سختی، EC، TDS و کدورت) بعد از خروج از دستگاه تصفیه آب با نانو ذرات گیاهی نسبت به کیفیت آب ورودی به دستگاه تصفیه آب کاهش به سزایی داشته است. در بررسی میزان تاثیرگذاری این فیلتر تقویت شده با گیاه آلوئه‎ورا مشخص گردید که این فیلتر دارای قدرت مناسب در حذف پارامترهای فیزیکی و شیمیایی آب است که میتوان از آن در تصفیه آبهای آلوده مورد استفاده در فرایندهای خانگی و شرب استفاده کرد. Manuscript profile -
Open Access Article
12 - Providing Nanofiber Membrane of Nylon-6 Master-batch, Ag, Chitosan, Rosemary, and Investigating the Anti-oxidant and Antimicrobial effect for Packaging in Food Industries
Farideh HaddadIn the present research, nylon 6-silver (NS)/ Chitosan (CS)/Rosemary master-batch nanofibers was provided in order to be used in packaging food. Morphology and structure of the nanofibers was investigated using the Scanning Electron Microscope (SEM) and Fourier-transfor MoreIn the present research, nylon 6-silver (NS)/ Chitosan (CS)/Rosemary master-batch nanofibers was provided in order to be used in packaging food. Morphology and structure of the nanofibers was investigated using the Scanning Electron Microscope (SEM) and Fourier-transform infrared spectroscopy (FTIR). The antibacterial activity of synthetic nanofibers was evaluated for E. Coli and S. Aureus bacteria. The antioxidant activity of oxidant glucose of glucose oxidase and Rosemary as well as the function of the provided membranes in packaging and maintaining strawberry was investigated. Morphology and diameter of synthetic nanofibers were determined with SEM images. According to the results of the carried out investigations on the deterrent effect of silver on the activity of glucose oxidase of 70/30 NS-CS sample was selected as the optimum for subsequent studies, and based on the results, the highest enzyme activity (79.5%) with 0.05 grams of glucose oxidase was obtained. The antibacterial test of the membranes showed the perfect antibacterial activity of such membranes against the negative and gram-positive and gram-negative bacteria. In addition, the FTIR spectroscopy approved the presence of glucose oxidase, silver, and Rosemary in synthetic membranes. Manuscript profile -
Open Access Article
13 - Effect of voltage and distance in electrospinning of Gelatin
Abolfazl Mozaffari Mazeyar ParvinzadehGelatin is a natural polymer with strong polarity. It has molecular chains connected through strong hydrogen bonds, constituting a 3D macromolecular network. Because of its many merits, such as its biological origin, biodegradability, biocompatibility and commercial ava MoreGelatin is a natural polymer with strong polarity. It has molecular chains connected through strong hydrogen bonds, constituting a 3D macromolecular network. Because of its many merits, such as its biological origin, biodegradability, biocompatibility and commercial availability at relatively low cost, gelatin has been widely used in the pharmaceutical and medical fields. Electrospinning is a simple and versatile technique to generate nano to micrometer fibrous structures which are very similar to the natural febrile extracellular matrix (ECM). Morphology of electrospun fibers depends on solution, device and environmental parameters. Then in this research, we electrospinning 9 samples in different device conditions 3 different voltage (10,12,15 kV) and 3 different distance (distance between nozzle to collector:TCD) (10,15,20 CM). we surveyed FIBERS CHARACTERISTICS in device electrospinning parameter by SEM and FTIR tests that they observed nanofibers in the average standard deviation of them were 10-15% and their range varies also were between 79 to 139. and I also understood by increasing the voltage as well as the TCD, more fibers can be obtained with less beads and more uniformity Manuscript profile -
Open Access Article
14 - Adsorption Isotherm and Kinetic Study of 4- Nitrophenol Removal From Aqueous Solutions onto Carbon Nano Fibers
پروین غربانیNitroaphenol compounds and toxic dyes are considered to be the main pollutants of wastewater of various industries. These synthetic organic compounds are very toxic and one of the most persistent pollutants in the environment. Developing a simple and effective method to MoreNitroaphenol compounds and toxic dyes are considered to be the main pollutants of wastewater of various industries. These synthetic organic compounds are very toxic and one of the most persistent pollutants in the environment. Developing a simple and effective method to remove non-degradable pollutants into non-hazardous products is one of the main challenges in environmental studies. In this research, adsorption capacity removal of 4-nitrophenol (4NP) from aqueous solutions using carbon nanofibers (CNF) was investigated in a batch system by considering the effects of various parameters like contact time, adsorbent dosage, pH and initial concentration. Optimum conditions for (4NP) adsorption were found to be initial pH≈2 , carbon nanofiber (CNF) dose≈ 0.02 g and equilibrium time≈ 80 min. Results show that removal efficiency of the 4NP increased by increasing 4NP concentration and decreased by increasing the CNFs dosage and pH. Based on correlation coefficients, Langmuir gave the best fit for 4NP adsorption onto CNF. Also, the kinetic studies indicate the adsorption of 4NP onto CNF is followed a pseudo- second order kinetic. Manuscript profile -
Open Access Article
15 - Effect of Polypropylene Fibers on Strength and Thermal Resistance of Concrete
Jamal Ahmadi Hossein Aghajanloo -
Open Access Article
16 - Strength Characteristics of Clay Mixtures with Waste Materials in Freeze-Thaw Cycles
Mahya Roustaei Mahmoud Ghazavi -
Open Access Article
17 - Investigation of Mechanical Properties of Lithium-Based Geopolymer Composites Reinforced with Basalt Fibers
R. DavoudianDehkordi A. A Nourbakhsh H MonajatiZadeha -
Open Access Article
18 - Electrospinning Nanofibers Gelatin scaffolds: Nanoanalysis of properties and optimizing the process for tissue engineering functional
mohammad jalili abolfazl mozaffari mazeyar gashti masoud parsania -
Open Access Article
19 - Electrospinning Nanofibers Gelatin scaffolds: Nanoanalysis of properties and optimizing the process for tissue engineering functional
Mohammad Jalili abolfazl mozaffari Mazeyar Gashti Masoud Parsania -
Open Access Article
20 - Effect of Electrical Potential on the Morphology of Polyvinyl Alcohol/ Sodium Alginate Electrospun Nanofibers, Containing Herbal Extracts of Calendula Officinalis for Using in Biomedical Applications
Seyed Rasoul Tahami Nahid Hasanzadeh Nemati Hamid Keshvari Mohammad Taghi Khorasani -
Open Access Article
21 - Predicting Hook -Shaped and Concrete Steel Fibers Adhesion Parameters Using Artificial Neural Networks
amir ebrahim akbari baghal Amir ebrahim akbari bagalGiven the importance of using steel fibers in reinforcement of concrete, in the present study using artificial neural networks to predict the behavior of hook -shaped steel fibers from concrete. Due to the constraint of comprehensive laboratory data, data obtained from MoreGiven the importance of using steel fibers in reinforcement of concrete, in the present study using artificial neural networks to predict the behavior of hook -shaped steel fibers from concrete. Due to the constraint of comprehensive laboratory data, data obtained from limited element analysis has been used as neural network input. The fibers are used to simulate the fiber and the Abacus software. In the limited element model, the interactions between fibers and concrete are simulated using the concept of the transitional area of the common surface whose parameters are obtained using the reversed limited element method and the use of the out -of -the -way experimental test results on a fiber sample. After assessment of the numerical model results with the empirical results, the results were extracted for effective parameters of the fibers and based on them using neural networks. Forecasting of the outburst has been carried out by the Multi-Layer Artificial Neural Networks and the Rear Publishing Algorithm, with Marcoradet-Clberg optimization techniques. The results show that the neural network model presented in this study, due to the ability to use more variables in modeling and more accurate results, is an effective way to predict the fiber's extrusion force. Manuscript profile -
Open Access Article
22 - Strengthening of Simple Prestressed Beams Using Carbon and Glass Reinforcing Polymer Fibers
Seyed Fathollah Sajedi Amin Toolabi ShaykhiIn this study, after evaluating the capability of Abaqus software and ensuring the results, two non-reinforced prestressed beams as reference models and 24 reinforced prestressed beams with carbon and glass reinforcing fibers and application of concrete with strength of MoreIn this study, after evaluating the capability of Abaqus software and ensuring the results, two non-reinforced prestressed beams as reference models and 24 reinforced prestressed beams with carbon and glass reinforcing fibers and application of concrete with strength of 30, 40 and 50 MPa and prestressed cables with diameters of 16, 20 and 22 mm were modeled. After numerical analysis of prestressed concrete beams with and without reinforcing fibers, their bearing capacity was investigated. After numerical analysis of prestressed concrete beams with and without reinforcing fibers, their bearing capacity was investigated. It was concluded that in the simple reinforced concrete and prestressed beams, cracks resulting from tensile damage in the middle cross section of the beams with maximum stress are continuously reduced with a gentle slope towards the supports. In simple reinforced concrete and prestressed beams, the highest stresses were created in the tensile reinforcements at the bottom of the beam and in shear reinforcements, the stress get started in the middle section of the beams and exhibited its maximum in the lower part of the beam section. In addition, in simple prestressed concrete beams, the capacity was increased by raising the number of prestressed tendons from 1 to 2 and 3. The capacity of beams with 3 tendons has increased by 79% and 22% compared to the beams with 1 and 2 tendons, respectively. The bearing capacity of prestressed concrete beams with C50 consumption category were increased by 6% and 5% contrasted to the prestressed concrete beams made of C30 and C40 concrete categories, respectively. By comparing the reinforced models using carbon reinforcement sheets in comparison with the glass type, the bearing capacity of beams containing carbon fibers are enhanced by about 12% (on average) compared to different types of glass fibers. Manuscript profile -
Open Access Article
23 - Simulation and Evaluation of Seismic Performance of Concrete Structures Reinforced with CFRP Fibers Based on Nonlinear Static Analysis
Kamiar mahboubi mohammad saberiMore than a decade, the issue of improving the quality of building engineering knowledge infrastructure is considered as one of the most important cases. Deterioration and loss of columns and decks of bridges, beams, columns, walls of buildings are attributed to some ca MoreMore than a decade, the issue of improving the quality of building engineering knowledge infrastructure is considered as one of the most important cases. Deterioration and loss of columns and decks of bridges, beams, columns, walls of buildings are attributed to some cases such as the age of the structure, environmental destructive factors, weak design or implementation and also change of structures’ usage, and procedures of the old regulations or events such as earthquake. On the other hand, strengthening the location of the implementation of reinforced concrete structures is not usually taken into consideration. Therefore, strengthening the proper location of the structure and increasing the structural strength and reducing the cost of retrofitting have been of great importance to the attention of various researchers. The main purpose of this study is to investigate reinforced concrete structures in various modes of reinforcement of elements using FRP fibers. For this purpose, at first, three concrete structures with 5, 7 and 9 stories were designed according to the 2800 seismic regulations in SAP 2000 software and were subjected to static nonlinear analysis for which overlapping analysis has been carried out with a reverse triangular loading pattern. This structure is reinforced so that it can use the maximum structural capacity and also the columns enter the nonlinear stage after the beams. In the next step, we consider the structure in various ways such as strengthening the entire structure, reinforcing the frames, reinforcing the elements separately, strengthening the external frame of the structure, strengthening the internal frames (structural core), etc., so that through extracting the base cutting, floor drainage, the internal force of the elements and the amount of FRP consumed, we obtain the most optimal method for reinforcing the structure, which provides the functional level of LS safety with reinforcement by FRP. Manuscript profile -
Open Access Article
24 - Investigation of flexural strength of ultra-high performance concrete reinforced with steel fibers using multiscale finite element model
Amir ebrahim akbari bagal Ahmad maleki ramin vafaeipoorThe main purpose of this study is to develop a finite element model to study the effect of steel-shaped fibers on the flexural strength of ultra-high performance fiber concrete. For this purpose, in order to numerically simulate, a multi-scale finite element model was d MoreThe main purpose of this study is to develop a finite element model to study the effect of steel-shaped fibers on the flexural strength of ultra-high performance fiber concrete. For this purpose, in order to numerically simulate, a multi-scale finite element model was developed in which concrete was modeled as a homogeneous and uniform material and steel fibers were randomly distributed inside it. In order to make more realistic assumptions, the area of adhesion between the fibers and the concrete is also considered. After validating the results of finite element model with the results of experimental tests, the effect of parameters such as volume fraction and adhesion of steel fibers on the strength characteristics of flexural strength of ultra-high performance concrete reinforced with fibers has been studied numerically. The results indicate that the effect of using fibers on the amount of energy absorption by fiber reinforced concrete is much greater than its effect on other characteristics of this type of concrete and especially the use of fibers in low fiber volumes has a very significant effect on energy absorption so that for 0.5% of the volume fraction of steel fibers, an increase of about 17 times compared to the sample of super-reinforced concrete without fibers can be resulted Manuscript profile -
Open Access Article
25 - Evaluation of Rheological and Mechanical Properties of Lightweight Concrete Containing Different Percentages of Polypropylene and Zeolite Fibers
Abdolkarim Abbasi Dezfouli Rezbeh AghajaryLightweight concrete is one of the most important and efficient materials in the modern construction industry and has a variety of applications. Proper application of lightweight concrete can have many positive influences on the construction process of concrete structur MoreLightweight concrete is one of the most important and efficient materials in the modern construction industry and has a variety of applications. Proper application of lightweight concrete can have many positive influences on the construction process of concrete structures. The possibility of application in the most geographical regions, utility of natural and cheap materials, high speed, low cost compared to the large volume of operations and its ductility due to the geometric shapes of the design, good performance and very high resistance, resistant to compressive forces and tensile strength, energy absorption and cracking stability are the prominent features of lightweight structural concretes. The main purpose of this research was to investigate the rheological and mechanical properties of the lightweight concrete containing different percentages of zeolite and polypropylene fiber separately. In this research, applying laboratory method, the rheological properties of fresh lightweight concrete (soft concrete) and the mechanical properties of hardened lightweight concrete at the ages of 7 and 28 days have been evaluated. According to ASTMC 39 standard, two samples of lightweight concrete without zeolite and polypropylene at the ages of 7 and 28 days have been prepared and mechanically evaluated. Then, in continuation of preparing of the light concrete samples prepared based on ASTMC 39 standard, three mixing designs with different percentages of polypropylene fibers (0.9, 1 and 1.1%) and 3 mixing designs with different percentages of zeolite (5, 10 and 15%) , at the mentioned ages were examined and compared with the base samples in the laboratory, which resulted in the following findings: Lightweight concrete samples containing zeolite had a higher electrical resistance than lightweight concrete samples containing polypropylene and the highest compressive strength was related to lightweight concrete samples containing 15% zeolite. This is equivalent to 400.75 kg / cm3 at the age of 28 days. Manuscript profile -
Open Access Article
26 - Experimental and numerical evaluation of rheological and mechanical properties of self-compacting concretes containing steel fibers and PET using response surface method (RSM)
hamed basser Taleb Moradi Shaghaghi hasan afshin saleh ahari saeed mirrezaeiIn the modern characteristics of concrete design based on daily needs, the use of recycled materials is an important and basic principle. Therefore, in the present study, PET (Polyethylene Terephthalate) has been substituted for fine aggregates in self-compacting concre MoreIn the modern characteristics of concrete design based on daily needs, the use of recycled materials is an important and basic principle. Therefore, in the present study, PET (Polyethylene Terephthalate) has been substituted for fine aggregates in self-compacting concrete. The aim of this study is to produce and optimize the mechanical and rheological properties of environmentally friendly self-compacting concretes. Input variables in the mixtures include (PET) as a substitute for a percentage of fine aggregates, steel fibers, powder stone as a substitute for a percentage of cement weight, and lubricant as a percentage of powder material weight. The studied responses are slump flow, L-box ratio (H2 / H1), compressive and tensile strengths. Mixing schemes were designed and studied using the Central Composite Design (CCD) method, which is one of the RSM (Response Surface Methodology) methods. The results demonstrated that with increasing PET, the rheological and mechanical properties of the mixtures decreased while the fibers effectively improved the reduction of strengths. Applying mathematical models provided by ANOVA, multi-objective optimizations were performed to maximize compressive strength by the RSM method and an optimal mixing scheme based on experimental results was proposed. Manuscript profile -
Open Access Article
27 - Photocatalytic self-cleaning properties of lanthanum and silver co-doped TiO2 nanocomposite on polymeric fibers
Hadi Fallah Moafi -
Open Access Article
28 - Experimental Study of Modulus of Elasticity, Capillary absorption of water and UPV in Nature-Friendly Concrete Based on Geopolymer Materials
Mohammadhossein Mansourghanaei Morteza Biklaryan Alireza Mardookhpour -
Open Access Article
29 - Experimental and numerical modeling for shear strength of hybrid fiber reinforced concrete beams with stirrups
Mahdi Moradi Mehran Sheikhmohammadi Seyyed Hossein Aletaha -
Open Access Article
30 - Evaluating the Effect of Fiber Addition on Seismic Performance of Segmental Tunnel Lining
Saeed Farokhi Zadeh majid moradi Ata Hojatkashani -
Open Access Article
31 - Performance Characteristics of Carbon-nanofiber Blended Self Compacting Concrete
Sivakumar M V N -
Open Access Article
32 - Preparation of Double-layer Nanofibers Base on Hydrogel, Silver nanoparticles, and Fatty Acid using electrospinning technique
ensieh ghasemian lemraski elaheh khajehali sahar yariToday, electrospinning method is widely used to produce nanofibers based on polymers. Poly (vinyl-alcohol) and chitosan are among the most widely used polymers in biochemistry and medicine, especially in wound healing and tissue engineering. In this project, an attempt MoreToday, electrospinning method is widely used to produce nanofibers based on polymers. Poly (vinyl-alcohol) and chitosan are among the most widely used polymers in biochemistry and medicine, especially in wound healing and tissue engineering. In this project, an attempt has been made to make polymeric materials and silver nanoparticles, nanofibers with protection and antimicrobial capabilities. Electrospinning method for making bilayer nanofibers, top layer containing poly (vinyl alcohol) and chitosan containing silver nanoparticles or silver ions as antimicrobial layer, and bottom layer containing polyvinylpyrrolidone and fatty acid as layer Moisturizes the skin of injured skin. Morphology and structure of nanofibers produced using various methods such as XRD X-ray spectroscopy, FTIR infrared Fourier transform spectroscopy, thermal weighing method or TGA, X-ray energy diffraction spectroscopy (EDAX-EDS), electron microscopy method (SEM), and finally the transmission electron microscopy (TEM) method was examined. The results of the instrumental analysis indicate the production of polymer fibers with a diameter in the range of 200-500 nanometers, which indicates the successful production of nanofibers, and also structural analyzes confirm the presence of silver nanoparticles and silver ions. The results of microbial tests show that nanofibers containing silver ions have a greater antimicrobial effect than silver nanoparticles. Manuscript profile -
Open Access Article
33 - Investigation of the release kinetics of strong optical photosensor Hypericin from Poly (e-caprolacton) nanofibrous mat
محمودرضا سهرابی فائقه پورحجت شهاب شریعتیTransdermal drug delivery systems with controlled release are a useful device for local transfer of pharmaceutical components to the damaged site and healthy layers of the skin. These devices are particularly suitable for wound healing in cases where long-term treatment MoreTransdermal drug delivery systems with controlled release are a useful device for local transfer of pharmaceutical components to the damaged site and healthy layers of the skin. These devices are particularly suitable for wound healing in cases where long-term treatment and frequent wound dressing exchange are needed. In this research, due to the superior feature of nanofibers, high surface to volume ratio, electrospinning technique was used to make dressings, for antimicrobial photodynamic therapy (aPDT), using biocompatible and biodegradable polymers such as poly (Ɛ-caprolactone) (PCL). Optimized conditions (voltage, flow rate nozzle to collector distance rotation) for obtaining nanofibers PCL/Extract (10, 30, 50%V/V) are as follows: Voltage of 12kV for nanofibers PCL and PCL-E50, and 20kV for PCL-E10 and PCL-E30, flow rate of 0.1ml/h for PCL and PCL-E50, and 0.5 ml/h for PCL-E10 and PCL-E30, and distance of 100 mm for all the nanofibers. Manuscript profile -
Open Access Article
34 - Evaluation of Forage Quality in Intercropping of Corn and Cowpea Affected by Foliar Application of Urea and Vermicompost
Ghodratollah Shah Karami farrokh rahimzadehkhoei Masoud Rafiei Bahram Mirshekari Varharam RashidiOne of the most important elements in forage crop production and management is high forage qualitative. In order to evaluation the effect of urea foliar application and vermicompost fertilizer on forage qualitative in corn (Zea mays L.) – cowpea (Vigna unguiculata MoreOne of the most important elements in forage crop production and management is high forage qualitative. In order to evaluation the effect of urea foliar application and vermicompost fertilizer on forage qualitative in corn (Zea mays L.) – cowpea (Vigna unguiculata L.) mix cropping, an experiment was lay out in RCBD as strip- split plot with four replications in Khorramabad temperate region during 2011- 2012. Urea foliar application and control, using vermicompost fertilizer and control, and corn + cowpea mix cropping (sole corn and sole cowpea, and %75:%25, %50: %50, %25: %75, corn:cowpea) were the factors. Urea foliar application and using vermicompost fertilizer had better performance than controls. The lowest pure fibers and the highest ash, pure protein, amount of forage energy, digestible dry matter, and protein yield were achieved from Urea foliar application and using vermicompost fertilizer and %75:%25 and %50: %50, corn:cowpea mix cropping rates. Results showed that foliar application significantly affected forage quality. Manuscript profile -
Open Access Article
35 - The Novel Synthesis Route for 3-Poly (vinylbenzyl)-5,5-Dimethylimidazolidine-2,4-dione Nanofibers and Study of Its Antibacterial Properties
Bozorgmehr Maddah -
Open Access Article
36 - Effect of Hydroxyapatite Nanoparticles on Differentiotion of Mesenchymal Stem Cells into Bone cells in Polycaprolacton/Keratin/Hydroxyapatite Scaffolds
Mahboobeh Mahmoodi Mina Kalantari Marjan MirhajThe human body process can spontaneously repair small bone defects, while large bone defects cannot be repaired without medical interventions. Efforts to eliminate these shortcomings have led to the foundation of bone tissue engineering. In this research, polycaprolacto MoreThe human body process can spontaneously repair small bone defects, while large bone defects cannot be repaired without medical interventions. Efforts to eliminate these shortcomings have led to the foundation of bone tissue engineering. In this research, polycaprolactone/keratin scaffold and Polycaprolactone/keratin/hydroxyapatite scaffold were fabricated using electrospinning method and were evaluated. Then, in order to evaluate the cellular differentiation, adipose tissue-derived mesenchymal stem cells were cultured on scaffolds and the process of differentiation of mesenchymal stem cells into bone cells for 7 and 14 days was investigated by alkaline phosphatase and alizarin red test. Increase of the activity of the enzyme alkaline phosphatase, the presence of the minerals and the red-orange-color extended on the scaffolds containing hydroxyapatite nanoparticles that confirmed the presence of Ca + 2 , demonstrated the differentiation of mesenchymal cells into bone cells. Therefore, the results of this study suggest that the polycaprolactone/keratin/hydroxyapatite scaffold is a suitable substrate for proliferation and differentiation of stem cells for bone tissue engineering. Manuscript profile -
Open Access Article
37 - Fabrication of Nanofibers Core - Shell Oxide by One Step Electrospinning Method
حجت رفیعی پور محمد رضا واعظی اصغر کاظم زادهIn this paper, core - shell nanofibers were synthesized by single stage electrospinning. To achieve on this aim, a coaxial needle was used, and oxides precursor were solved in polyvinyl alcohol (PVA) solution, and injected by separate syringes which connected to one pum MoreIn this paper, core - shell nanofibers were synthesized by single stage electrospinning. To achieve on this aim, a coaxial needle was used, and oxides precursor were solved in polyvinyl alcohol (PVA) solution, and injected by separate syringes which connected to one pump. Calcination was done on synthsised core – shell nanofibers. The morphology and microstructure of nanofibers were examined by field emission scanning electron microscope (FE-SEM), transmission electron microscopy (TEM) and energy-dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). The final structure is ZnO as shell and SnO2 as core. The core diameter and the shell thickness nanofiber from TEM image are approximately 45 nm and 25 nm, respectively. The average diameters of as-electrospun and calcined core - shell nanofibers are about 175 and 79 nm, respectively. Manuscript profile -
Open Access Article
38 - The Effect of Gelatin-aloevera Nanofibers on Collagen I Gene Expression in the Skin of Male Mice after Microneedling
Asadolah Shahrani Maryam Bananej Parvin Mansouri Henghameh Alibeik Nahid NickhahThe skin is prone to mechanical injuries and damage and the skin collagen changes with age. Herbs and aloe vera gel are used experimentally and traditionally in the skin repair and rejuvenation. In this study, the effect of gelatin-aloe vera nanofibers on the expression MoreThe skin is prone to mechanical injuries and damage and the skin collagen changes with age. Herbs and aloe vera gel are used experimentally and traditionally in the skin repair and rejuvenation. In this study, the effect of gelatin-aloe vera nanofibers on the expression of collagen I gene after skin microneedling was investigated in male mice under standard laboratory conditions. Skin microneedling was performed on the backs of the tested mice. Groups were subjected to treatments with saline, aloe vera gel, and gelatin-aloe vera nanofibers for 48 h. The expression of collagen I gene was evaluated through sampling and purification of tissue RNA by Real time PCR method. According to the results, skin injury resulted in a significant reduction in the expression of the collagen I gene in the treatment groups compared to the control group. In comparison, treatment with aloe vera gel and aloe vera/gelatin nanofibers significantly increased gene expression compared to the model group. Furthermore, the existing Glucomannan increased gene expression at the site of injury by passing through pores. Manuscript profile -
Open Access Article
39 - طراحی و بهینه سازی پیچ کامپوزیتی پلی لاکتیک اسید/ شیشه زیست فعال برای کاربرد های ارتوپدی
عماد حسینی انوشه زرگر خرازیConsidering their suitable strength and ability to properly stabilize, metal screws are used to repair bone fractures. پیچ های فلزی به دلیل استحکام مناسب جهت ترمیم شکستگی های استخوان مورد استفاده قرار می گیرند. اما مشکلاتی چون ضریب کشسانی بالای فلزات نسبت به استخوان های MoreConsidering their suitable strength and ability to properly stabilize, metal screws are used to repair bone fractures. پیچ های فلزی به دلیل استحکام مناسب جهت ترمیم شکستگی های استخوان مورد استفاده قرار می گیرند. اما مشکلاتی چون ضریب کشسانی بالای فلزات نسبت به استخوان های بدن که منجر به پدیده پوکی استخوان می گردد و نیز امکان رهایش یون های فلزی در موضعی که می توان منجر به ایجاد عفونت های موضعی یا مشکلات سیستمی شود ،جایگزینی پیچ های غیر فلزی به جای انواع فلزی را در دستور کار محققین قرار داده است. در این مطالعه کامپوزیت متشکل از فاز زمینه پلیمر پلی ال-لاکتیک اسید و فاز تقویت کننده الیاف شیشه زیست فعال جهت طراحی پیچ مد نظر قرار گرفت. ابتدا ضرایب کشسانی در آنالیز میکرو تخمین زده شد سپس به آنالیز ماکرو توسط نرم افزار آباکوس 6.11 برای مدلسازی با وضعیتهای دولایهای تشکیل شده از الیاف تک جهته و رندوم (UD/R) و سه لایه ای متشکل از الیاف تک جهته ،الیاف با زاویه 20± درجه نسبت به اعمال نیرو و الیاف رندوم (UD/±20/R) با درصد های مختلف از ضخامت لایه ها انتقال داده شد. نتایج نشان داد ترکیب کامپوزیت سه لایه با درصد لایه های(25/10/65) دارای مناسب ترین پاسخ مکانیکی می باشد. در این نمونه با درصد لایه های (25/10/65) مدول خمشی 7/22 گیگا پاسکال ،استحکام خمشی 347 مگاپاسکال و ضریب کشسانی در راستای طولی 8/24 گیگا پاسکال تخمین زده شد. که مقداری از ضریب کشسانی استخوان کورتیکال بیشتر است. پیچ کامپوزیتی طراحی شده جهت تثبیت شکستگی ارتوپدی از استحکام لازم برخوردار است و به عنوان کاندیدی جهت جایگزینی پیچ های فلزی قابل استفاده است. Manuscript profile -
Open Access Article
40 - Prediction of Adhesion Parameters of Hook-shaped Steel Fibers and Concrete Using Artificial Neural Networks
Amir ebrahim akbari bagalAs steel fibers are important reinforcement materials in concrete, in this study, the behavior of hook-shaped steel fibers from concrete is predicted through the use of artificial neural networks. In the absence of comprehensive laboratory data, data obtained from finit MoreAs steel fibers are important reinforcement materials in concrete, in this study, the behavior of hook-shaped steel fibers from concrete is predicted through the use of artificial neural networks. In the absence of comprehensive laboratory data, data obtained from finite element analysis was used for modeling. The simulations are carried out using ABAQUS software's finite element method in 3D. Using the concept of the transition zone of the interface, whose parameters were obtained by inverse finite element analysis and experimental tests conducted on a sample of fibers, this model has been developed to simulate the interaction between fibers and concrete. On the basis of the results of the numerical model validated against the experimental results, the effective parameters of the fibers were extracted, and a neural network was then constructed based on the results. A multilayer forward perceptron artificial neural network and back-propagation training algorithm are used to predict pull-out force, with Marquardt-Lonberg optimization applied. The results demonstrate that the neural network model presented in this research is an effective method for predicting the pull-out force of fibers from concrete, in part because it allows the use of more variables in modeling, as well as delivering more accurate results. Manuscript profile -
Open Access Article
41 - Impact of Freezing and Thawing Cycles on Mechanical Performance of Carbon Fiber-Reinforced Cement-Stabilized Sand
M. Nourmohammadi Z. Aghaei M. BayatIn civil engineering, natural soils often lack the strength required for intended loads. Soil improvement techniques, such as using cement and fibers, are employed to bolster mechanical properties for engineering structures. This study evaluates the efficacy of cement-s MoreIn civil engineering, natural soils often lack the strength required for intended loads. Soil improvement techniques, such as using cement and fibers, are employed to bolster mechanical properties for engineering structures. This study evaluates the efficacy of cement-stabilized sand reinforced with carbon fibers under freezing and thawing cycles. Key variables investigated include cement and carbon fiber content, curing periods, and freeze-thaw cycles. Results show significant enhancements in unconfined compressive strength (UCS) with the addition of cement and carbon fibers. For instance, specimens with 10% cement and 2% carbon fiber achieved UCS values of up to 1717 kPa, 1521 kPa, and 1347 kPa under varying freeze-thaw cycles at 28 days. This combination also reduces crack formation by increasing strain at failure points. Specimens with 2% carbon fibers and 10% cement exhibited the highest failure strains under freeze-thaw cycles. However, increasing freeze-thaw cycles led to decreased UCS, although carbon fiber-reinforced specimens showed more resilience. The study highlights the efficacy of combining carbon fibers and cement for reinforcing sandy soil under freeze-thaw conditions. Cement enhances UCS during stabilization, while carbon fibers improve strain at failure, enhancing soil deformability and mitigating failure mechanisms. This research provides insights into optimizing soil stabilization methods for civil engineering projects in challenging environmental conditions. Manuscript profile -
Open Access Article
42 - Synthesis of polymer matrix nanocomposite with carbon fibers and analysis of its strength properties
S.M.M. ShafieiIn polymer-based nanocomposites, carbon nanofibers have been used to improve mechanical properties in various applications. In this research, the tensile properties of carbon nanofibers have been used to create carbon-epoxy nanocomposite and improve the mechanical prope MoreIn polymer-based nanocomposites, carbon nanofibers have been used to improve mechanical properties in various applications. In this research, the tensile properties of carbon nanofibers have been used to create carbon-epoxy nanocomposite and improve the mechanical properties of epoxy nanocomposite, and the effect of the weight percentage of carbon nanofibers on the mechanical properties of epoxy nanocomposite has been investigated. Epoxy with weight percentages of 1.0, 5.0 and 1.5 carbon nanofibers were produced and their mechanical properties were investigated. The results showed that the use of even a small percentage of carbon nanofibers can lead to the improvement of mechanical properties. Manuscript profile
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