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Editorial
Management and Economics Wood
Management and Economics wood
Amir Reza Taheri; Abbas Tamjidi; Ajang Tajdini
Abstract
Background and Objectives: Organizations depend on marketing, innovation and learning indicators to increase organizational performance and competitive advantage. By taking advantage of appropriate marketing and innovation capabilities, in addition to profitability and competitive ...
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Background and Objectives: Organizations depend on marketing, innovation and learning indicators to increase organizational performance and competitive advantage. By taking advantage of appropriate marketing and innovation capabilities, in addition to profitability and competitive advantage, product life cycle prolongation and stability in the competition scene are provided for organizations. The rapid changes in production technologies necessitate the strengthening of human resource capabilities for all elements. Organization is necessary. Methodology: The effect of marketing capabilities, innovations, learning of employees on the performance of wooden office furniture companies with the approach of structural equations has been investigated. The statistical population of this research consists of managers and engineers working in wooden office furniture companies located in industrial towns in Tehran and Alborz provinces. Sampling method was classified and Crecy-Morgan table was used to determine the sample size (92 people). Initial effective indicators were selected by studying the available sources and the conceptual model of the research considering the performance of the organization (company) as a dependent variable and marketing, innovation and learning variables as independent variables. The main tool for collecting information for this research was a questionnaire. Correlation and confirmatory factor analysis and structural equation modeling based on partial least squares method were used to investigate the research hypotheses and analyze the structural relationships between variables. Results: The results showed that innovation, marketing and learning capabilities had a positive effect on the performance of wooden furniture companies. In addition, these capabilities complement 96.9% of the changes in the dependent variable of the company's performance. The results of the model quality evaluation index show that marketing capability (strong effect), innovation capability (medium effect), learning capability (weak effect) have the greatest impact on company performance. Finally, the results of this study remind the various companies producing wood furniture industry products that are constantly looking to export their goods that, unlike the somewhat non-competitive domestic market, to compete with other companies in target markets, should try. Due to factors such as marketing, innovation and learning, improve products quality, reduce costs and ultimately increase company performance. Conclusion: The use of appropriate marketing methods, innovative capabilities and increasing human resource capabilities in order to strengthen organizational learning in wooden furniture industry companies will strengthen the performance and position of the mentioned companies.
Research Paper
Pulp and paper
Seyed Mehdi Manzour-olajdad; Omid Ramezani
Abstract
Background and Objectives: Our country has been importing various kinds of wallpaper from different countries for many years. With the increase of foreign exchange problems, the local production of wallpaper and its self-sufficiency has been proposed as a suitable solution. On the other hand, currently, ...
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Background and Objectives: Our country has been importing various kinds of wallpaper from different countries for many years. With the increase of foreign exchange problems, the local production of wallpaper and its self-sufficiency has been proposed as a suitable solution. On the other hand, currently, domestic companies are producing paper from white waste paper, which is not justified for use as printing and writing grades due to many problems. However, many companies in the country are producing white grades from white waste paper, the use of which as a base paper in the production of decorative paper or wall paper has not been scientifically investigated. The purpose of this research is to study and investigate the possibility of producing wall paper from recycled white paper produced in the country.Methodology: The stages of this project were carried out in 6 separate and consecutive phases, which include: 1) determining the quality characteristics of the papers; 2) preparation of coating material formulation with starch as binder; 3) preparation of coating material formulation with latex and starch as binder; 4) coating of papers with the prepared coating formulations ; 5) Coating papers and non-woven fabric (Non-Woven) with polyvinyl chloride (PVC); 6) Application of four-color printing on the selected samples of coated papers. For this purpose, first, samples of papers produced by several Iranian companies were acquired and they were transferred to the laboratory of Biosystems and Bioproducts of Shahid Beheshti University for coating and performing the necessary treatments. In order to perform the mentioned treatment on the paper samples, various chemical substances were used, including calcium carbonate powder, kaolin, titanium oxide, corn starch, latex and PVC powder. With this aim, coating solutions with different percentage of solids were prepared steadily and with trial and error using various combinations of these materials (with a total of 110 and 124 parts). Then, these coated solutions were added on various domestic base papers (mostly recycled). Finally, the image of a flower was printed in four colors on the most desirable coated papers.Results: In determining the quality characteristics of base papers, including measurements of water absorption, ash content, thickness, permeability to air, tensile strength, tear resistance index and burst resistance index, two paper samples produced by two companies of Pardis Paper and Tabriz paper were selected as the best and considering the amount of ash, Tabriz paper was introduced as the base paper more suitable than other local papers. Further, after applying the coating material, coated papers with a relatively favorable appearance and whiteness percentages of about 60 to 85 were obtained, and finally, based on the results, a significant relationship was found between the increase in the solids percentage of the coated solutions and the whiteness percentage of the coated paper. Also, after the printing operation on the selected samples, Rasha Superkraft and Tabriz Kraft papers were introduced as the best samples. Also, the highest quality of printing was reached with PVC on Pars white paper with 16% PVC, on whitetop Rasha with 28% PVC and on non-woven fabric (non-woven fabric) with 28% PVC compared to the weight of the paper.Conclusion: The conclusion of the results of this research are listed below:A) The best solid percentage of coating solution (concentration of the mixture) was 41-46%.b) The best combination of binder and pigment, equal to 100 + 12 + 12 = 124 parts and the ratio of the dry weight of the coating mixture added to the dry weight of the base paper is equal to 12%.c) The highest whiteness obtained by adding calcium carbonate + titanium oxide + starch.t) The most suitable concentration of starch that can be used in the coating solution is 15%.c) The best coating and uniform and good coating appearance was obtained on Rasha Superkraft paper with the formula: kaolin + titanium oxide + latex with a whiteness of 77.7% and on Tabriz kraft paper with the formula: kaolin + titanium oxide + latex, with a whiteness of 71.8%. If higher whiteness is desired, using calcium carbonate instead of kaolin would give a better result.
Research Paper
Physics and Mechanical Wood
Javad Torkaman; Ramin Naghdi
Abstract
Background and purpose: Dynamic methods (non-destructive) work on the basis of creating tension without failure in the samples and save time and costs for evaluating mechanical properties. Knots or the encapsulated branches are the most important factor in the grading of wood. Therefore, the objectives ...
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Background and purpose: Dynamic methods (non-destructive) work on the basis of creating tension without failure in the samples and save time and costs for evaluating mechanical properties. Knots or the encapsulated branches are the most important factor in the grading of wood. Therefore, the objectives of this research are: detection of knots by non-destructive methods, measuring the dynamic modulus of elasticity of beech log using stress waves, and the effect of knot size on the speed of stress waves Subsequently, the value of dynamic modulus of elasticity.Materials and methods: The studied area of Shafarood series 11, which is located in the southern part of the Shafarood watershed, starts at an altitude of 500 meters and continues up to an altitude of 1650 meters. From this area, Five number of beech trees were cut and divided into three equal parts of three meters by transverse cutting, and according to the size of the knots, the properties of density, stress waves velocity Subsequently, the dynamic modulus of elasticity were measured. From the tangential image of the external indicator and the radial image of the internal indicator by using the Digimizer image4 software, the characteristics of each knot such as the diameter and angle of the knot were measured. For non-destructive detection of beech tree knot, ultrasonic tomography, stress wave velocity and CT scan methods were used. In the stress waves velocity method, a Fakopp microsecond timer device was used to measure the time of stress waves velocity. In the radiographic method as well to prepare CT scan images, A digital ground column device with two detectors made in France belonging to a medical clinic was used. To measure the density, 30 cylindrical stems with knots of small, medium and large classes were used, and according to the relationship between density and stress wave velocity, the value of dynamic elasticity modulus was calculated and evaluated. The diameter of the knot along the length of the stem, the density and the dynamic modulus of elasticity of the beech tree stem were measured. To analyze the data at the 95% confidence level, the one-way Anova test was used, and to determine the normality of the data and the homogeneity of the variance, the Kalmograph Smirnov and Leven tests were used. To compare the means, Tukey's test was used by using Spss software.Results: In the detection of beech tree knot with the three mentioned non-destructive methods, the results show the existence of limitations in each method. As the ultrasonic tomography is not able to detect knots inside the beech tree trunk and the stress wave method also does not detect very small knots. The accuracy of the CT scan method in detecting the knot is high, but the cost of its detection is high. According to the growth stages of the beech tree, factors such as growth speed, branch encapsulation speed and natural pruning are different. The origin of the branch is pith of the stem. As a result, the number and size of the created knots are different along the tree. Therefore, most of the small knots are created in the main trunk of the tree. The diameter of the knot has also increased with the increase in the height of the stem. The knot has increased the density. The density results have shown that the samples with large, medium and small knots have significant differences. Considering that the ultrasonic tomography method is based on the reduction of density, it is not able to detect the knot. But in the radiography method, the parts with higher density are seen in light color and the parts with lower density are seen in darker color. The size of the knot is effective on reducing the speed of stress waves and thus reducing the dynamic modulus of elasticity of wood. In comparison with the samples without knots, the samples with small, medium and large knots reduce the modulus of elasticity by 20%, 50% and 70% respectively.Conclusion: in general, among the non-destructive methods, only the CT scan method is able to detect small knots and evaluate the clear wood and defects. In comparison with the control sample (without knots), with increasing the size of the knot, the value of the density increases and the stress wave velocity decreases Subsequently, the dynamic elasticity modulus of the samples decreases.
Research Paper
Wood Modification and Wood Preservation
Yaser Hamzavi; danial harandi; Fathollah Niazi; Seyyed Mohsen Haji Seyyed Javadi
Abstract
Background and objectives: Painting on wood became popular in Iran during the Safavid period and reached its peak during the Zand and Qajar periods. The art of painting and writing inscriptions on wood as one of the unique arrays in Iran has been forgotten and their technical and pathological studies ...
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Background and objectives: Painting on wood became popular in Iran during the Safavid period and reached its peak during the Zand and Qajar periods. The art of painting and writing inscriptions on wood as one of the unique arrays in Iran has been forgotten and their technical and pathological studies will greatly help to preserve and perpetuate such works. Preservation of wood in historical buildings, where color arrays are also applied, is a complex task. The challenge of this work is related to the multiple material characteristics of the work, the type of interventions and the selection of protective chemicals that should be considered in these works. In fact, by fully understanding the work, it is possible to provide a protection solution for it. The purpose of this article is to know the materials, structure and damage of the different layers of the historical headstones of the Taqvi House in Gorgan.Methodology: The wooden lion heads of the Taqvi House in Gorgan, which have written inscriptions along with plant motifs and frames, are the study samples of the current research. The type and amount of the sample was chosen according to the existing uncertainties as well as the test method. In total, four wood samples and four paint samples were prepared. For the technical study of these works, transmission microscope, Dino-Lite plus digital microscope, scanning electron microscope (SEM) equipped with EDS detector were used. Also, under standard laboratory conditions, mushroom cultivation and wood acidity were measured.Results: The black spots in the examination with a digital microscope indicate the presence and growth of biological factors on the surface of wood, which were sampled in a part of them to cultivate and identify the fungi. Initial observations with a digital microscope indicate the destruction of wood components caused by biological factors and the reduction of wood strength and cohesion. In the first investigation, according to the cross-sections of all the samples (three samples), it was found that the samples are broad-leaved woods. The vessels are evenly distributed. In the tangential section, single-celled and multi-celled wood rays can be seen, the width of which reaches about 25 cells. The size of the vessels is almost the same and of a homogeneous and scattered type of vessel. In this sample, two to four vessels are stuck together. The average size of the vessels was measured to be 59 micrometers. Also, the frequency of vessels per square millimeter was calculated to be 130 vessels per millimeter on average. In two samples 2021.G.T.3 and 2021.G.T.8, the vessels are heterogeneous, separated and their cross section is relatively round. Heterogeneous holes and part of the aperture can be seen and some of them are tiled. The diameter of the vessels is specific from spring and summer wood. In the tangential section, single-celled or multi-celled wood rays are observed. In the continuation of the studies, the study samples were examined with a scanning electron microscope with different magnifications. The cell wall in a sample is weakened and is collapsing. Also, the growth of fungi can be clearly seen among the wooden structure. In the other two samples, the cellulosic walls are severely damaged and we see dissociation and rupture between the cellulosic layers.Conclusion:The results of this study showed that the wood used for historical lion heads is beech and mazo wood. Also, fungi such as Aspergillus terius, Alternaria, Aspergillus niger and Cladosporium were identified in the wood structure. In the following, the destruction of the cell wall and the decay of the wood structure were identified. Also, azure blue, syringe red, white flowers, as well as a mixture of carbon black and iron black colors have been used on historical wood as patterns and writings. This study can be very important for the proper preservation of historical wooden works of Gorgan region.
Research Paper
Wood Modification and Wood Preservation
Hamid reza Zarey; Reza Hajihassani; seyedeh masoomeh; Kamyar Salehi
Abstract
Background and Objectives: Wood has some limitations in properties and applications due to its natural nature, which need to be modified. Wood modification is usually done with different aims and methods. One of the wood modification methods is thermal treatments in order to improvement of dimensional ...
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Background and Objectives: Wood has some limitations in properties and applications due to its natural nature, which need to be modified. Wood modification is usually done with different aims and methods. One of the wood modification methods is thermal treatments in order to improvement of dimensional stability and biological resistance. But, it is surely affected on physical and mechanical properties of wood. Wood thermal modification in presence of oxygen causes the oxidation of its chemical structure which leads to decrement of physical and mechanical properties. Therefore, elimination of oxygen in thermal modification can reduce its destructive effects. In current study, the effect of thermo-oil process on the function of white rot fungus has been investigated. Moreover, the effect of this process on engineering properties of birch and pine wood species was evaluated.Methodology: In this study, two wood species of birch (Betula sp.) and pine (Pinus sp.) cut into the desired timbers. Heat treatment of the prepared timbers was carried out in a cylinder which equipped to the pressure and vacuum system. Also, industrial recycled oil was used for heat treatment of the timbers. The temperature and time treatment were considered 195 °C and 5 hours, respectively. At the end of the process, the used oil was drained into the oil storage tank and the timbers were removed from the cylinder after applying vacuum. In order to investigation of biological resistance as well as physical and mechanical properties (water absorption and swelling, density, mass loss, bending strength, compression strength parallel to the grain and impact strength) test specimens were prepared from the treated and control timbers based on the standard. The SPSS software was used for statistical analysis. The results were statistically analyzed based on a One-Way ANOVA method.Results: Results revealed that thermo-oil treatment can reduce the functionality of white rot fungus and also its efficiency on physical and mechanical properties of both wood species. Moreover, the results showed that this process improved the physical properties and reduced the mechanical properties, except compression strength parallel to the grain.Conclusion: Thermo-oil treatment at high temperature causes structural changes of wood and affects its physical and mechanical properties. Also, the structural changes caused by heat treatment can be an effective and inhibiting factor to functionality of white rot fungus on physical and mechanical properties of wood.
Research Paper
Chemical conversion
Ramin Vaysi
Abstract
Background and aim: Every year, large amounts of species adapted to the semi-arid environment of Tehran planted. Meanwhile, planted plane tree (Platanus orientalis) and eldar pine (Pinus Halepensis var. Eldarica) tree in Tehran, in addition to creating a green and lively urban space, can also play a ...
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Background and aim: Every year, large amounts of species adapted to the semi-arid environment of Tehran planted. Meanwhile, planted plane tree (Platanus orientalis) and eldar pine (Pinus Halepensis var. Eldarica) tree in Tehran, in addition to creating a green and lively urban space, can also play a big role in absorbing heavy metals and components in the polluted air of Tehran. This study and it aim was accomplished on identification and comparison of the heavy metals in the wood, bark and leaves of planted plane tree and eldar pine tree by using flame atomic absorption method.Materials and methods: In this study, 20 separate test samples of leaves, wood, and bark of planted elder pine and plane tree were randomly selected from the 4th district of Tehran. According to the TAPPI standard tests, the leaf flour, wood and bark of the samples and their ash percentage were measured. Then with the help of 63% nitric acid and for one hour, the solution containing heavy metal was separated from the ash. In this research, atomic absorption spectrophotometer was used to determine the type and percentage of metal ions absorbed in the wood, bark and leaves of plane tree and eldar pine tree.Results: The results showed that the most ash was found in plane tree bark and the least in plane tree wood. The highest amount of iron ion absorption was found in plane tree leaves, while the lowest amount of iron ion absorption was found in plane tree wood. The amount of iron ion absorption in eldar pine bark is more than its wood and leaves and in oriental plane leaves is more than its wood and bark. The highest amount of potassium ion absorption was observed in eldar pine leaves and the lowest was in eldar pine bark. The amount of potassium ion absorption in eldar pine leaves was higher than its wood and bark, and in plane tree, bark is higher than its wood and leaves. In addition, the absorption of potassium ion is more in plane tree than in eldar pine. The highest amount of copper ion absorption was observed in eldar pine leaves and the lowest amount was observed in plane tree wood. The rate of absorption of copper ions in leaves is higher than the bark and wood of both species. In addition, the absorption of copper ions in eldar pine is more than that of plane tree. The highest amount of lead ion absorption was observed in the bark of eldar pine and the lowest amount was observed in plane tree and eldar pine wood. The amount of lead ion absorption in the bark was more than in the leaves of both species and in eldar pine was more than in plane tree. The highest amount of zinc ion absorption was found in oriental plant leaves and the least in oriental plant wood. The rate of absorption of zinc ions in the bark of eldar pine is more than its leaves and wood and in oriental plant leaves is more than its bark and wood. The highest amount of nickel ion absorption was found in plane tree and elder pine leaves and the lowest in oriental plant wood. The rate of absorption of nickel ions in oriental plant and eldar pine leaves is higher than in their bark and wood. In addition, between the two species, the rate of absorption of nickel ions in eldar pine is higher than that of plane tree.Conclusion: So that, the results showed that the leaves and bark of both species have a great role in the absorption of heavy metal in the air. In addition, the importance of the eldar pine species in absorbing heavy metal such as nickel, zinc, lead, iron and copper is more than the plantain species due to its evergreen nature. Eldar pine and plane tree wood showed the least importance in absorbing heavy metal. While the importance of bark in absorbing lead is the highest. In other words, in urban areas like Tehran, where air pollution is very important, planting eldar pine species seems to be more effective than plane tree.
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