Research Paper
Physics and Mechanical Wood
shahrzad omrani ghahjaverstani; amir lashgari; mahran roohnia
Abstract
Non-destructive tests today play a vital role in human life. Non-destructive evaluation technology is widely used in industries, especially wood based industries and wood based products and has led to advances in Strength grading lumber, determine the disadvantages of wooden materials, Inspection of ...
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Non-destructive tests today play a vital role in human life. Non-destructive evaluation technology is widely used in industries, especially wood based industries and wood based products and has led to advances in Strength grading lumber, determine the disadvantages of wooden materials, Inspection of timber and wooden structures. The purpose of this research was to estimate the flexural strength of dynamic tests and compare them with the results of static standard tests in two Forest Pine species (Pinus sylvestris) and Rush (Fagus orientalis). The results of the comparison of the estimation of the modulus of elasticity and the estimated modulus of rupture by a non-destructive free vibration method in a free supported beam with similar results from the static test showed a very good correlation So, according to calculations done by applying a safety coefficient of 18% for beech species and 11% for pine species, a non-destructive vibration test can be substituted by a static destructive standard test for estimating the factors mentioned in these two species.
Research Paper
Management and Economics wood
Ajang Tajdini; Ahmad Reza Eskandari; Shademan Pourmousa
Abstract
In the present study, we have evaluated the behavior of consumers in the decision-making process to purchase domestic and foreign household furniture. In this study, the statistical population was the total number of household wooden furniture customers, of which 385 were selected based on the table ...
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In the present study, we have evaluated the behavior of consumers in the decision-making process to purchase domestic and foreign household furniture. In this study, the statistical population was the total number of household wooden furniture customers, of which 385 were selected based on the table of Krugis-Morgan and by random sampling method. After conducting initial research and studies, considering the issues raised and the importance of the subject and determination of the research objectives, the 5 latent variables have been identified as cultural, preferential, sales, quality and beauty factors as the effective indicators for purchase of wooden household furniture and selection of imported products in comparison with domestic products were designed. To collect inferential data, a researcher made questionnaire and for library data, the study of resources, theses and research articles in this regard were used. Data were analyzed, by SPSS software in the descriptive statistics and by Lisrel software to determine the relationship between variables for structural equations. The results showed that the research model has been fitted in the first-grade and in the structural model. In measurement model, the measurement indices have created some meaningful factor loadings. This issue shows that this model has correctly been determined from theoretical literature and the criteria of this measurement have been recognized correctly. This caused a high validity of the measurements ‘tools. Also, all the mentioned latent variables and its dimensions as the structures of the proposed structural model effect on customer preferences in the decision-making process of foreign and domestic household wooden furniture purchase.
Research Paper
Management and Economics wood
farzad haghighirad; amirreza abtahi; amirmahyar torabi
Abstract
In this paper, barriers to the export of furniture from Iran have been identified and ranked using interpretative structural modeling (ISM). In order to identify the barriers to export, first the research background was investigated and a list of barriers was extracted. Then, with a number of experts ...
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In this paper, barriers to the export of furniture from Iran have been identified and ranked using interpretative structural modeling (ISM). In order to identify the barriers to export, first the research background was investigated and a list of barriers was extracted. Then, with a number of experts in the field of furniture production and sales, in-depth interviews and semi-structured interviews took place. The integration of barriers from theoretical studies and field studies was considered as the final list. In the next step, the relationship between the barriers was investigated pairwise, and the matrix of paired comparisons was completed. based on interpretive structural modeling and final conceptual model, the level of each of the barriers are recognized. Modeling results indicate that Iran's weak political relations with other countries are the main driver of poor export. Secondly, exchange rate fluctuations, lack of supply of raw materials and poor relations with embassies are also among the root causes.
Research Paper
Pulp and paper
ali barzan; hossein resalati; ali ghasemian; ahmadreza saraeyan; ghasem asadpour
Abstract
In this study, the effect of pigment composition on the properties of paper prepared from CMP pulp was studied. There for 3 different pigment combinations (100% calcium carbonate (GCC), 70% calcium carbonate and 30% kaolin clay (70GCC30Clay) and 70% calcium carbonate and 25% gritty and 5% titanium dioxide ...
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In this study, the effect of pigment composition on the properties of paper prepared from CMP pulp was studied. There for 3 different pigment combinations (100% calcium carbonate (GCC), 70% calcium carbonate and 30% kaolin clay (70GCC30Clay) and 70% calcium carbonate and 25% gritty and 5% titanium dioxide (70GCC25Clay5TiO2)) were made with anionic starch, latex and dispersersant and Used for coating. Physical properties included (surface roughness of the paper, Ash content and Apparent density) And the optical properties included (brightness, absorption and diffusion coefficient) and paper resistance characteristics including tensile strength, bursting resistance, tear strength based on standard TAPPI standardized measurements and Using factorial design, analysis of variance was performed and the mean of paper properties was compared with Duncan's test. The purpose of this research is to achieve the best combination for coating the paper with the improvement of physical and optical properties and maintaining resistance properties. By adding clay and dioxide titanium to calcium carbonate, the roughness of the paper surface decreased The highest roughness of the surface of the paper in the diet was observed for the control paper and the lowest was seen in the treatment of 70GCC30Clay surface. Also, the highest degree of brightness is related to 70GCC25Clay5TiO2 treatment. The highest index of tensile strength and burst strength index was related to gypsum treated paper (GCC) and also the highest tear strength index for treated paper at level 2 (70GCC30Clay).
Research Paper
Composite wood products
Mohammad Ghofrani; ali mohamadi
Abstract
This study investigated the comparative tension and compression strength of detachable edge joints in MDF and particle boards. Five pieces of each samples were provides in L shape with the size of 20*20 cm according to D 1761 ASTM. Fittings were applied in three types: cross, hexagonal shape and plastic ...
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This study investigated the comparative tension and compression strength of detachable edge joints in MDF and particle boards. Five pieces of each samples were provides in L shape with the size of 20*20 cm according to D 1761 ASTM. Fittings were applied in three types: cross, hexagonal shape and plastic fitting with 2 types of counter sink and butt screw were used. The results showed that the highest amount of tension strength was in cross shape metal joints and highest compression strength in hexagonal joints. Also the lowest strength of both tension and compression was observed in plastic joints. According to results, the joints with counter sink screws had higher strength than butt screw, and the failure place in this samples was like crevice in the bottom of boards. The data showed that the tension strength of all three fittings were higher than compression strength. The highest bearing of tension stress was in MDF with glue and dowel, counter sink screw and cross shaped fitting and the lowest was in particle boards without dowel, butt screw and plastic strips. The highest bearing of compression stress was in MDF with glue and dowel joint, hexagonal metal strip and counter sink screw, the lowest was seen in particle board without dowel, butt screw, and plastic strip.
Research Paper
Pulp and paper
ali ghasemi chahrdehi; Esmaeil Rasooly Garmaroody; Omid Ramezani; ghasem asadpour
Abstract
The aim of this study was to investigate the effect of storage and bleaching of cotton fiber on stability of optical properties of Bond paper. For this aim, industrial unbleached cotton fiber pulp with freeness 13°SR, in two types of fix and agitating was stored for 3-15 days in room temperature ...
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The aim of this study was to investigate the effect of storage and bleaching of cotton fiber on stability of optical properties of Bond paper. For this aim, industrial unbleached cotton fiber pulp with freeness 13°SR, in two types of fix and agitating was stored for 3-15 days in room temperature and after that bleached with hydrogen peroxide. Then, standard handsheets was made from bleached pulp and after air-dried, aged in UV and thermal methods and measured their optical properties. Results showed that agitated samples have more brightness and whiteness and less yellowness than fixed ones and by increasing of storage time this numbers be much and less, respectively. In case of UV treated samples, the brightness and opacity of fixed samples decreased and agitated ones increased. The brightness of fixed and agitated samples with thermal treatment showed up and dawn trend, respectively. Also, UV and thermal treatments, especially in fixed samples lead to much yellowness and much whiteness in agitated ones. Therefore, agitated storage method better than the fixed one so that before and after bleaching present suitable optical properties. In addition, paper made from agitated storage samples has more desirable characteristics and influence of temperature more than UV in present and longtime.
Research Paper
Physics and anatomy
ali hasanpoor tichi; mojtaba rezanezhad
Abstract
In this study, biometrics, physical and microscopic properties of Ficus carica wood were investigated. Therefore, three healthy Ficus carica trees in Mazandaran province have been selected and cut. Three discs of 5 cm thickness were prepared along the tree (diameter at breast height, 1.9 m height and ...
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In this study, biometrics, physical and microscopic properties of Ficus carica wood were investigated. Therefore, three healthy Ficus carica trees in Mazandaran province have been selected and cut. Three discs of 5 cm thickness were prepared along the tree (diameter at breast height, 1.9 m height and near the crown). In the transverse direction, 2 × 2 × 2 cm test specimens were sequentially taken from the pith to the bark and examined for physical and biometric properties of the fibers. Then the biometric properties of fibers including fiber length, fiber lumen diameter, fiber diameter and cell wall thickness were measured. Physical properties including basic density, oven dry density, longitudinal shrinkage, radial shrinkage and tangential shrinkage were calculated. Microscopic sections of three surfaces (transverse, tangential and radial) of Ficus carica tree was prepared and the anatomical characteristics of the wood of this species were determined precisely and indexed by IAWA. Anatomical studies near the pith and bark of this wood revealed differences. The most important of these differences are the presence of Tyloses in the vessel lumen near the pith and the absence of it in the near bark, homogeneous rays near the bark and heterogeneous rays in the near pith, the mean tangential vessel diameter near larger bark (105 μm) than near pith (70 μm) and wood rays were wider near the bark than near the pith. Also Ficus carica tree was diffuse porous hardwood species, distinct growth ring, Axial parenchyma vasicentric and Banded, Simple perforation plates Intervessel pits alternate and containing prismatic crystals in parenchyma. The results showed that there were significant differences in both the transverse and longitudinal directions of Ficus carica tree in terms of fiber length, fiber lumen diameter, fiber diameter and cell wall thickness. As biometric properties of fibers increased from pith to bark.
Research Paper
Mechanical conversion of wood and wooden fittings
Barat ali Keshtegar; Mehrab Madhoushi; Alimorad Rashidi; mahdi mashkour
Abstract
In this research, the effect of Polyvinyl acetate (PVAc) adhesive reinforced with modified carbon nanofibers (CNF) were studied in three levels (0%, 0.4%, 1.5%) on the strength properties of joints commonly in the furniture industry. Modified carbon nanofibers were used as chemically modified surface ...
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In this research, the effect of Polyvinyl acetate (PVAc) adhesive reinforced with modified carbon nanofibers (CNF) were studied in three levels (0%, 0.4%, 1.5%) on the strength properties of joints commonly in the furniture industry. Modified carbon nanofibers were used as chemically modified surface to improve the dispersion in polymer matrix. The bonding of the test specimens were made using of cut out medium density fiber board (MDF) pieces with desired dimensions and dowel wooden with 6, 8 and 10 mm in diameter, and penetration depth at three levels using polyvinyl acetate adhesive reinforced with modified carbon modified nanofiber. Totally, we have 27 treatments with three replicates. The evaluation of the bending moment capacity of test specimens made with freshly formulated adhesive carried out and the effect of other variables was performed on the joints made under tensile loading at a speed of 3 mm/min. The results showed that increasing the weight percent of carbon nanofibers, the diameter of the wooden dowel and the penetration depth and the moment capacity compared to the control samples was increased by 1.6, 1.5 and 1.3 times, respectively. The 0.4% w/w carbon nanofibers, 10 mm diameter and L3 wooden dowel penetration depth had the greatest effect on the strength of the joints.
Research Paper
Pulp and paper
somayeh heydari; Ahmad Reza Saraeyan; Mohamadreza Dehghani firozabadi; Alireza Shakeri; babak shokri
Abstract
Ethylene vinyl alcohol (EVOH) copolymer is of semi crystalline materials with excellent barrier properties to gases. Also, it has shown outstanding chemical resistance. Despite its low gas permeability, EVOH copolymer displays poor water and water vapor resistance. In this study, Trimethoxymethylsilane ...
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Ethylene vinyl alcohol (EVOH) copolymer is of semi crystalline materials with excellent barrier properties to gases. Also, it has shown outstanding chemical resistance. Despite its low gas permeability, EVOH copolymer displays poor water and water vapor resistance. In this study, Trimethoxymethylsilane (as hydrophobic coating) was deposited by Plasma Enhanced Chemical Vapor (PECVD) method on the coated paper with Ethylene vinyl alcohol in order to improve the paper's barrier properties of moisture transmission. Coating by PECVD method was done in the certain conditions of time 6 min and pressure 300 m Torr. Different treatments were applied for power including 50, 70 and 90W.Then contact angle was measured in order to determined improvement of the paper's barrier properties of moisture transmission . The result showed that papers which were coated with Trimethoxymethylsilane had higher contact angle water 55.7% more than the control. The results revealed that the best condition was obtained by 50 W power. The structural and chemical properties of deposited layer were observed with Fourier Transform infrared spectroscopy- Attenuated Total Reflectance (FTIR-ATR) and Energy Dispersive X-ray Spectroscopy (EDS). The results confirmed bonding of silane on the surface EVOH polymer.
Research Paper
Mechanical conversion of wood and wooden fittings
Morteza Nazerian; Alireza Rezaian; Mohamma Shamsiyan
Abstract
Bending strength of I-joist lightened via two methods of crinkleing and honeycombing using poplar species (Popolus deltoids) and eucalyptus (Eucalyptus spp) was studied. Investigated variables consisted of: a) type of flange, b) configuration of lightened core layer in web and c) thermal-pressure treatment ...
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Bending strength of I-joist lightened via two methods of crinkleing and honeycombing using poplar species (Popolus deltoids) and eucalyptus (Eucalyptus spp) was studied. Investigated variables consisted of: a) type of flange, b) configuration of lightened core layer in web and c) thermal-pressure treatment surface layers of web. Flange type at two levels: 1) LVL from poplar wood and 2) eucalyptus massive wood, configuration of web core layer at two level too: 1) crinkle and 2) honeycomb and type of treatment applied on surface layers of web which were prepared from poplar layies with 3 mm thick at two levels: 1) thrmo-compressed treated and 2) untreated veneers were selected. Mechanical properties of beam consisted of modulus of rapture (MOR) and modulus of elasticity (MOE) were selected and tested as dependent variables. Obtained results were analyzed in full factorial plot, statistically. After determination of results significance results, means of values were classified by Duncan Multiple Range Test (DMRT). Results showed that using LVL from poplar unlike its low density had higher MOR and MOE values compared with eucalyptuse massive wood. Besides, in order to lighten beam, using honeycomb configuration in web core layer gave more strength to beam in comparison with crinkle configuration. Treatment of surface layers of web had not effect on bending strength, statistically.
Research Paper
Pulp and paper
Mohsen Mohammadi Achachlouei; Fahimeh Yousefi
Abstract
Paper is a dominant tool that is traditionally used for recording human knowledge and cultural heritage. Paper as organic material is at risk of biodegradation processes by various microorganisms including fungi, which cause irreversible degradation, color modification and instability of the historical ...
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Paper is a dominant tool that is traditionally used for recording human knowledge and cultural heritage. Paper as organic material is at risk of biodegradation processes by various microorganisms including fungi, which cause irreversible degradation, color modification and instability of the historical papers. Thus, the utilization of appropriate conservation methods and restoration treatments to minimize the adverse effects of fungi on historical papers have received great attention. Recently, Benomyl as an antifungal revealed a significant inhibitory effect on the fungal growth on the historical papers. In this study, the effect of Benomyl on gall ink as a popular and important ink used in cultural heritage was investigated. In a first step of the evaluation, the gall ink was prepared based on the historical recipes and then was implemented on surface on filter paper. The prepared samples were dipped into 100 ppm Benomyl-ethanol solution and aged after drying. The effect of Benomyl on gall ink was evaluated by the pH values of aqueous extracts, CIE Colorimetry, paper strengths, FTIR-ATR spectroscopy and SEM microscopy. Results indicated that the Benomyl in concentration of 100 ppm had no adverse effect on the gall ink and paper surface. However, dipping of paper in the Benomyl-ethanol solution resulted in a significant loss of paper strengths. In order to overcome this problem, it would be necessary to use a suitable solvent or another technique such as spraying for surface application of Benomyl.
Research Paper
Chemical conversion
Milad Poladi; Seyed Hassan Sharifi; Seyed Majid Zabihzadeh; Mostafa Nikkhah Dafchahi
Abstract
Cellulose is the most abundant bio-polymer and also has many potential and applications, Therefore, in order to convert it to solvable cellulose in many commercial solvents, it is necessary to modify the cellulose structure with a variety of methods of derivation. Cellulose derivatives have an increasing ...
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Cellulose is the most abundant bio-polymer and also has many potential and applications, Therefore, in order to convert it to solvable cellulose in many commercial solvents, it is necessary to modify the cellulose structure with a variety of methods of derivation. Cellulose derivatives have an increasing share in the cellulosic products marketing and it is used in various industries such as sanitary, pharmaceutical, food and industrial., Carboxymethyl cellulose is one of the most important commercial cellulose ether derivatives. The purpose of this study was to investigate the conversion of alpha-cellulose derived from the Deltoides pine species into a useful and more valuable product that called Carboxymethyl cellulose. In order to optimize and investigate the interaction of different process variables, response surface methodology (RSM) was used. For modeling the process, important operational parameters such as concentration of NaOH, ratio of Monochloroacetic acid to cellulose, temperature and the time of etherification as independent variables and the degree of substitution of the samples were considered as the desirable response. Analysis of variance and response level were used to create a function between variables and responses, and optimal conversion conditions were determined. The results showed that the best value presented in the optimal condition proposed by software for the degree of substitution was 31 percent for concentration of etherification, 1.09 for the ratio of Monochloroacetic acid to cellulose, 60 °C for the etherification temperature and 157 minutes for the etherification time.
Research Paper
Composite wood products
Fardad Golbabaei; Kamyar Salehi; Reza Hajihassani
Abstract
In this study, the composition of bagasse composite was investigated using different amounts of bagasse particles. Bagasse and cement particles are manufactured at levels (5, 10 and 15%) and percentage of calcium chloride as cement accelerating additive at two levels (3 and 2%) based on cement dry weight. ...
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In this study, the composition of bagasse composite was investigated using different amounts of bagasse particles. Bagasse and cement particles are manufactured at levels (5, 10 and 15%) and percentage of calcium chloride as cement accelerating additive at two levels (3 and 2%) based on cement dry weight. Then, the mixture was poured into a mold measuring 15 8 18 8 8 cm and the excess water was removed from the bottom of the mold and initially weighed 10 kg on the specimens. The specimens were removed from the mold after 48 hours and kept in a glass saturated room at 90% humidity for 14 days and then finally dried in a laboratory environment. The bending strength and physical properties tests were performed on the specimens. The results showed that bagasse particles had a significant effect on bending strength and other physical properties. The bending strength was highest in boards made with 10% bagasse particles.