Journal of Wood and Forest Science and Technology
Year:2018 | Volume:25 | Issue:1|Papers Count:12

Background and objectives: One of the common problems in the papermaking process is compounds and unwanted by-products such as pitch, sticky and foreign pollution in paper that each of these materials may come from various sources. The wood as raw material for pulping is an agent of these problems; because wood have contained hydrophobic materials such as wax, lipids, fatty acids, resin acids, hydrocarbons and etc. Pitch is the term that produces in the papermaking process and leads to considerably problems. The main destructive impacts of pitch, including blocking and hang lace to felt dewatering or drying cylinders occur that creates holes in the paper. Nowadays, some of the material to removal these problems on an industrial scale are used. Material and methods: In this study, after obtaining extractive compounds from bleached and unbleached CMP pulp, pulps were treated by 0. 2 units, equivalent of 0. 001 g of esterase enzyme in the water condition (H2O) and consistency of 8% at 50 0C for 45 min with mechanical mixing. Enzyme treatment for the unbleached and bleached pulp was done as separation stage; therefore, the effect of enzyme treatments in pulps using gas chromatography-mass spectrometry (GC/MS) was studied. Results: Generally, results of this study showed that treatment use with ethanol solvent, bleaching process leads to increasing the amount alkanes, 1 and 2 benzene di-carboxylic acid derivatives, alcohols, silica compounds and minor amounts of aldehydes and as well as lower the esters fatty acids, phenolic and ketones derivatives. There is also a trend in the presence of the enzyme except that ketones were not in pulp and fatty acids increased. Increase of silica compounds is due to three combinations of enzymes. In treatment with use of di-chloromethane solvent, bleaching process leads to increase of alkanes, ketones and silica compounds and reducing the fatty acids, esters of fatty acids, 1 and 2 benzene di-carboxylic acid derivatives, alkenes, aldehydes and phenolic derivatives. There is also a trend for the enzymes with the exception of aldehydes, alcohols, phenolic derivatives, ketones and amides not observed in any of the two pulp that of their destruction. In treatment with use of toluene solvent, the impact of bleaching as increasing of halo-alkanes, esters of fatty acids, 1 and 2 benzene di-carboxylic acid derivatives and aldehydes and reducing of alkanes and phenolic derivatives not observed. The use of enzymes in this solvent and in the unbleached pulp, high amounts of 1 and 2 benzene di-carboxylic acid derivatives, aldehydes and alcohols were presence in pulp. Conclusion: According to the results obtained from GC/MS, it can be said that esterase enzyme has good performance relatively compared to solvents. As previously mentioned the deposition of extractives in pulp and paper equipment leads to reduce the run-ability of the papermaking machine, causing a tear in the paper and eventually disability of operations and is involved in major economic losses. Triglycerides wood, especially in the factories that used softwoods as raw material, play an important role in the formation of pitch deposits. Therefore, the use of enzyme systems could have a key role in controlling of pitch.

Background and objectives: Urinary tract infections are one of most common infectious diseases. Urinary tract infections are caused by a group of pathogenic microorganisms such as bacteria Escherichia coli, Staphylococcus and Saprophiticus in the urinary tract. The infection occurs when bacteria enter the system through the urinary tract and reproduce in the bladder. A lot of people come annually for its treatment to clinics and hospitals and too much money is spent to treat these infections. Prevention of incidence of such diseases can avoid paying the high cost of treatment. Use of sanitary paper like toilet paper and sanitary napkins with antimicrobial properties can be a good way to prevent the occurrence these diseases through a continuous removal of germs and create an environment free from germs. Clay as a natural material with a history of use in the treatment of diseases can be a good option for this purpose. Materials and methods: As expected clay because of its negative charge causes to create the antimicrobial properties, in this study, in addition to clay, nanoclay as an antimicrobial agent used in the paper structure. These materials used to form a cover layer in concentrations of 1, 3 and 4 % wt. along with starch as a retention aid. Antimicrobial properties were examined on two Escherichia coli and Bacillus subtilis bacteria. Physical and mechanical properties, as well as optical characteristics (opacity) of the prepared papers, were evaluated. Results: The results showed that the presence of clay and nanoclay could lead to inhibition the growth of both Gram-negative of Escherichia coli and gram-positive of Bacillus subtilis bacteria. At reviews, the antibacterial effect was observed that the performance was better nanoclay compared with clay, and with the increasing the percentage use of these materials, its antibacterial properties increased, especially in nanoclay. It was also observed that the presence of clay and nanoclay increase amount of water absorption of modified paper, as well as caused increased resistance to air in the paper. In the review of the strength properties also observed that the presence of clay and nanoclay improved burst index, while the tear index did not change significantly. Conclusion: The results showed that nanoclay compared with clay because of its smaller dimensions and thus more specific surface area as a hydrophilic material and also containing inhibition properties against living organisms can be introduced as a material with a high application domain in creating antimicrobial properties in the paper and used.

Background and objectives: One of the most widely used wood products applied in wooden buildings as load bearing posts or beams is laminated strand lumber (LSL). Nano-zinc oxide is a chemical that has the potential to be used in the protection of LSL. The use of nano-zincoxide as an additive in LSL may affect its mechanical and physical properties. In this study, the effect of adhesive type (PF and pMDI) and nano-zinc oxide amount (0, 0. 5, 1, 1. 5 % based on strands weigth) on the physical and mechanical properties of LSL was investigated. Materials and methods: For this purpose, lSLs were made from Iranian beech using either a phenol formaldehyde (PF) or a polymeric methylene diphenyl diisocyanat(pMDI) adhesive and four loading levels of nano-zinc oxide. The mechanical and physical properties of the LSLs were then measured according to ASTM-D5456 and modified ASTM-D1037 respectively. Results: The results showed that the interaction between nano-zinc oxide treatment and the adhesive type was significant for MOE and IB while the interaction was not significant for MOR at the alpha level of 5%. Not only did nano-zinc oxide not reduce significantly the mechanical properties of the composites but it also increased partially the studied properties in most cases. Nano-zinc oxide with the lowest loading decreased the thickness swelling and improved the dimensional stability. The higher loadings did not result in any further improvement. Conclusion: In general, it can be concluded that the different levels of nano-zinc oxide can be used in treating laminated strand lumber composites made with PF and pMDI adhesives without having any negative effect on mechanical properties of the composites.

Background and objectives: Nowadays, some attempts are done to use nanoparticles as a preservative for wood. It seems that the using nanoparticles with polymeric materials could improve undesirable properties of wood such as dimensional stability and leaching of nano particles. In this study, physical properties and leach resistance of eastern cottonwood-polymers that treated with copper oxide nanoparticles were studied. Materials and methods: Wood samples with 20×20×20 mm dimensions were papered and then impregnated with polymers and nano copper oxide by full cell method. In this research variable factors were concentration of Polystyrene (40 and 80 percent) and nano copper oxide (0, 0. 4 and 0. 8 percent). After preparing Samples, they were immersed in 100 ml of DI water and their water absorption, volumetric swelling and leach resistance were calculated. Results: Obtained results showed that treated samples had less volume of water absorption and volumetric swelling. For example, the average water absorption and swelling volume after 168 hours immersion in water were 33. 5 and 4. 5 percent respectively for samples that treated by Polystyrene at concentration of 80 percent and nano copper oxide at concentration 8. 0 percent, while these values were 127 and 11. 8 percent respectively for control samples. The rate of leaching copper oxide in the presence of Polystyrene was less than 1% for all the treatments. Conclusion: Treating Wood with nano copper oxide in presence of Polystyrene reduced water absorption and improved dimensional stability. Moreover, these samples had a little rate of copper leaching.

Background and Aim: In recent years, has been increased production volume of polystyrene foams. These foams are applicable in food and packaging industries. Growing environmental concerns have created a need to develop biodegradable materials. Starch is a widely available, renewable, low cost, biodegradable and thermoplast (TPS). For this reason, starch generates a great interest at it is considered as promising alternative to synthetic polymers (as polystyrene). But poor mechanical property is a limited parameter to use this polymer. One of the important ways to reduce this limitation, is the improvement of the thermal and mechanical properties using of nanofiber cellulose as reinforcement of foam. But NFC gel is aqueous and it forms irreversible aggregates when dried. High moisture creates big cells in foaming and effect on foam properties. This subject limit using of NFC (nanofiber cellulose) to prepare polymeric composites. The aim of current research is using NFC (nanofibercellulose) to prepare NFC/TPS nanobiocomposite foam by extrusion mixing for better dispersion of NFC in matrix polymer and investigation on thermal and mechanical properties of foam. Materials and Methods: Granules powder of corn starch, glycerol, NFC gel, and azodicarbonamide have been used to make NFC-TPS nanobiocomposite foam. Glycerol (30 wt %) as plasticizer. NFC (0. 5, 1, 1. 5 wt %) as reinforcing agent and azodicarbonamide (0. 2 wt %) as blowing agent (BA) were used. Raw materials were mixed in a co-rotating two screw extruder. Then TPS/NFC/ BA granule was prepared. Then by using of these granules, nanobiocomposites foams were prepared under hot press (temperature higher than degradation temp of BA). The morphology of the samples studied by FE-SEM. The tests thermogravimetry (TGA), differential scanning calorymetry (DSC), dynamic-mechanical-thermal analysis (DMTA) were done on TPS/NFC nanobiocomposite foams for determination of the thermal and mechanical properties. Findings: FE-SEM images showed, that TPS/ NFC nanobiocomposite foam has higher and smaller pores in comparison TPS foam. This is due to nucleation effect of NFC. TGA showed thermal stability of TPS/NFC nanobiocomposite foam with increasing of NFC. DSC showed transition glass temperature has been increased with increasing of NFC content. The DMTA showed storage modulus and loss modulus increased with increasing of NFC content but tan delta decreased. The reason of this result is formation microcellular foam and reinforcement of the cell wall of foam by NFC. Conclusion: The results of research showed NFC improved thermal and mechanical properties of TPS/NFC foam. TPS/NFC foam had more unique and smaller in comparison of TPS foam.

Background and objectives: The banknote is one of the most important ways to transfer of the many of microbes to human and also human diseases. In this study, the anti-fungal effect of cellulose nanocrystal alone and with chitosan nanofiber on the common paper banknotes have been examined. Materials and Methods: Cellulose nanocrystals have been prepared using acid hydrolysis by H2SO4 from cotton linter. The diameter of the prepared cellulose nanocrystals and chitosan nanofibers was characterized by transmission electron microscopy (TEM). Firstly, the fungal contamination of the banknotes from four centers (bakery, butchery, passenger terminal and hospital) was evaluated. Then, in order to consider the antifungal activity of cellulose nanocrystals and chitosan nanofiber compound, stable emulsions with 1%, 2%, 4% and 6% concentrations have been prepared and then coated to the surface of banknotes using rolling coating method. Results: According to the TEM images, the diameter for cellulose nanocrystals and chitosan nanofiber was 5-20 nm and 45 nm, respectively. It can be concluded that the cellulose nanocrystals have been successfully prepared from cotton linter. The results showed most fungal spices found in banknotes from bakery, butchery, passenger terminal and hospital) are Aspergillus, Aspergillus niger and Penicillium respectively. Anti-fungal examination of paper banknotes covered with cellulose nanocrystals at concentration of 3% shows no significant antifungal activity on Penicillium fungi on paper banknotes from the hospital. In addition, the results also show that adding chitosan nanofiber at 1%, 2% and 4% concentrations have no antifungal effect on the surface of banknotes from bakery, butchery, passenger terminal and hospital, but adding chitosan nanofibers at 6% concentration shows the significant anti-fungal effect. The results show that cellulose nanocrystals had no antifungal effect alone effect alone on the banknote species, but it could improve the antifungal effect, adhesion, and stability of cellulose nanocrystals on the banknote surfaces. Conclusions: This study suggested a new approach to decrease the infection spreads through banknotes.

Background and objectives: Loranthus europeaus Jacq. is a threatening factor in Zagros forests. It is seen on various tree species. This study was conducted to investigate the effect of continental mistletoe (Loranthus europeaus Jacq. ) on carbohydrate, proline and chlorophyll content in Persian Oak (Quercus brantii Lindl. ), Montpellier maple (Acer monspessulanum L. ) and Almond (Amygdalus elaeagnifolia Spach. ) as its common hosts in Ilam forests. Materials and methods: Nine habitats with the mistletoe infested were selected in different forest areas of the Ilam province. From each habitat six infected trees of Quercus brantii, Acer monspessulanum and Amygdalus elaeagnifolia were sampled. These trees were in the same conditions of diameter, height, severity of infectious and aspect conditions. After that, the leaves were collected from healthy and infected branches. From each tree, four mature leaves were individually sampled from below and above the mistletoe clump in the host tree, the leaf of the mistletoe, and the leaf of the healthy branch of the host tree. For measuring the carbohydrate, proline and chlorophyll content, the leaves then transferred to the laboratory. Results: The results showed that the content of chlorophyll a, b and carbohydrate in almond and Persian oak had significant different in the various position including below and above of the mistletoe clump in the host tree, mistletoe leaves and uninfected branch. In addition, the highest levels of chlorophyll a and b were observed in the two mentioned-above tree species. A. monspessulanum species did not show significant difference in terms of proline, chlorophyll and carbohydrate in different sampling parts, but the highest amount of chlorophyll (2. 282 mg/g) and proline (0. 552μ m/g) was determined in L. europeaus. A significant difference was seen between chlorophyll b values of L. europeaus and below the clump, and the highest amount of this feature was in almond. The highest amount of carbohydrate (3. 017 mg/g) in the almond was in the mistletoe clump and tree leaves below it (2. 99 mg/g). In Persian oak, the lowest (2. 159 mg/g) and highest (3. 094 mg/g) amount of carbohydrates was observed in the L. europeaus and oak leaves below the clump, respectively. Furthermore, among the host trees, the leaves in the position above the mistletoe clump showed some differences and Q. brantii and A. monspessulanum had the most and lowest amount of carbo. The proline values were significantly different between mistletoe leaves and leaves of host trees. Highest amount of proline can be attributed to the leaves of the almond tree. Conclusion: The amount of features like proline, carbohydrate and chlorophyll were significantly different in diverse sites as well as in different sample leaves. In other words, it can be said that the hemiparasite mistletoe as a biological stress affects the physiological activity of forest trees, which differs from one species to another.

Background and objectives: Native juniper of Maymars is one of the valuable species in Mountainous forests of Golestan province and is one of the main pillars of natural ecosystems of Iran’ s mountainous forests. At the moment, most of these trees have the hardest biological conditions and they try to be survived. So it is needed to practice finding the protection and propagation ways to keep these plants. Material and methods: To recognize the best season and substrate, and also proper treatment to root the cuttings of Maymars, recent experiment was done with 5 levels of indole butyric acid (0, 1000 ppm, 2000 ppm, 4000 ppm & 8000 ppm) in 4 substrates contained perlite, perlite-cocopite (1: 1), Pumice and rooting substrate (combination of sand, perlite, cocopeat, vermicompost and peat moss) and 4 seasons of the year on Maymars cuttings with length 15 cm. The experiment was done in 3 replications, and each one contained 9 cuttings. The aim of the experiment was finding the best season; substrate and natural treatment to asexual propagate of this plant (cutting). At the end of each season, rooting percentage, root length, root numbers, fresh and dry weights of roots in each substrate and treatment were registered. Results: The result showed that the best season for rooting the Maymars cuttings is spring and the best substrate is perlit cocopeat (1: 1). The best rooting between all treatments was related to level 4000 and 1000 ppm of indole butyric acid in spring with more than 50% rooting. Lowest amount of rooting was related to all treatments of winter with fewer than 2%. Highest number of roots was seen in spring and level of 2000 ppm of indole butyric acid and also in perlit-cocopeat substrates (1: 1) and the fewest one was seen in pumice substrate. Maximum root length was seen in spring and it should be mentioned that between all substrates, the best ones were perlit – cocopeat, perlite and rooting substrate without any significant difference. Highest amount of root fresh and dry weight was resulted in spring. And also highest amount of root fresh weight was found in rooting substrate. On the other hand, the highest amount of root dry weight was seen in pumice substrates as well. Conclusion: So it can be concluded that to propagate Maymars cutting, spring is the best season with the best result of rooting. Also indole butirice acid is effective Plant Growth Regulator to propagate Maymars juniper. The best rooting between all treatments was related to level 4000 and 1000 ppm of indole butyric acid in substrate of perlit cocopeat (1: 1) in spring with more than 50% rooting.

Background and objectives: One of the important factors in planning and decision making for sustainable forest management in the context of sustainable development is assessment stakeholders and their attitudes towards forest sustainability criteria. The seven benchmarks of the Near East process for sustainable management of Iranian forests include: the size of forest resources, biodiversity, forest health and survival, forest resource production functions, forest resource conservation functions, socio-economic functions, and the legal, political and organizational framework. Materials and methods: The purpose of this study was to compare the attitudes of different forest managers in identifying sustainable management indicators in a part of central Zagros forests located in Kuhdasht city in west of Lorestan province. The practitioners included individuals from local communities, executive experts, and university professors who were selected through field studies and bibliographic studies. In this regard, 50 questionnaires were distributed among practitioners. Cronbach's alpha and SPSS16 software were used to determine the reliability of the questionnaires. Likert scale was used to evaluate the responses. Then, the status of the importance of the most important indicator of each criterion, proportional to its relative weight, was obtained from the attitude of three groups of forestry practitioners. Results and Conclusion: The results showed that the reliability of the questionnaire was 0. 729, which is indicative of acceptable reliability. Evaluation of the results of the opinions of the groups for each criterion and its related indicators showed that the two criteria for "protective functions" and "health, happiness and integrity" are the same. Finally, in order to investigate the significant relationship between the attitude of the practitioners, the Chi-I test or binomial test were used which did not show any significant difference between the attitudes of the three groups.

Background and objectives: One of the defense response strategies of trees against drought and pathogens is phenotypic variations of leaf and stomata. Furthermore, a certain mother tree can partly control phenotype of its offspring, and consequently, affect their tolerance to environmental stress. Therefore, in this study the effects of water deficit and bacterial pathogen on leaf and stomatal traits of healthy and dried trees, causing the decline of brant's oak in Kohgilouye and Boyer-Ahmad province, has been investigated. Materials and methods: Seeds of 4 healthy and 4 infected trees were collected from Khaeiz conserved area and planted into pots to assess the effect of the mother tree. After growing of seedlings, bacteria of Brenneria quercinia was inoculated to half of seedlings originated from both healthy and infected mother trees. After 40 days, half of the inoculated and non-inoculated seedlings, treated under water deficit for three weeks and the rest of them received full irrigation. Then, leafs of seedlings were harvested and measured by Image j 1. 43 software. After that, the experiment was performed in a completely random design analyzed, and the treatments were laid out in 2*2*2 (2 levels bacteria, 2 levels irrigation, 2 levels mother trees or genotype) and also the mean comparisons tests were done. Results: Results showed that the effect of bacteria is not significant on any stomata traits, but stomata width and stomata pore width were smaller in seedlings of water deficit treatment than fully irrigate seedlings. Also seedlings of dried trees had smaller stomata width. Water deficit caused to significant decrease of stomata perimeter and leaf width of half-sibling healthy trees, but the number of leaf teeth and vein of half-sibling dried trees were decreased under water deficit treatment that they were not significant for half-sibling healthy trees. The effect of bacteria was not similar on halfsibling of healthy and dried trees, so that perimeter, area and length of stomata and perimeter and base angle of leaf in non-inoculated seedlings of healthy trees were larger but after inoculation stomata area of half-sibling healthy trees were decrease and stomata length increased significantly. Inoculation of bacteria also leads to significant decrease of leaf area in half-sibling dried trees, but it did not have any effect on half-sibling healthy trees. Triple interaction of irrigation, bacteria and mother trees was significant for stomata pore width, as so, seedlings of healthy trees showed smaller stomata pore width under water deficit treatment, but bacteria has not negative effect on it. For seedlings of dried mother trees, these differences were not significant at any treatments, but the size of it was smaller than seedlings of healthy mother trees. Conclusion: Results of this study showed that half-sibling healthy trees have larger leaf and stomata traits. It demonstrated that these seedlings have more abilities to production and photosynthetic capacity. Furthermore, the water deficit had a more negative effect than bacteria on the decline of oak. Also half-sibling of healthy trees under water deficit condition could reduce evaporation with decreasing size of leaf and stomata traits. This decreasing size of stomata was observed under inoculation of bacteria, in contrary the offsprings of drought affected trees exhibited longer stomata than controls that made them more susceptible to water deficit stress and pathogen agent. Also it has been demonstrated that stomata and leaf characteristics can be conducted to identification of drought and bacterial disease resistance genotypes.

Background and objectives: In recent years the increasing population and urban development has caused the increase on recreational demand in natural areas. The Ghalehgol forest is located in Khoramabad country. Due to the geographical location, natural and historical attractions here is one of the important tourism area of Lorestan province. The aim of this study is estimating the recreation value of this region according to visitors' idea and investigation the influencing factors on willingness to pay for visiting the area. Materials and methods: The necessary statistics and information were collected through the completion of questionnaires by visitors that had independent income in spring of 2016. Generally, 252 questionnaires were completed by random sampling. 245 of these questionnaires for further analysis were selected. For this purpose, contingent valuation method was used. To investigate the factors affecting visitor’ s willingness to pay, the logit model was estimated using maximum likelihood. Then the aggregate elasticity and marginal effect analyze was conducted. Results: The results showed that 65% of the visitors are willing to pay for visiting the region. The variables of monthly income, distance of home and proposed price for entrance at the probability level of one percent and the variables of car owner and education at the probability level of five percent have statistically significant effects on the willingness to pay. Aggregate elasticity related to education and monthly income showed that in constancy of other factors, one percent increase in education and monthly income probability of willingness to pay increase 0. 95 percent and 0. 43 percent and for variables distance to home and proposed price decrease 0. 10 percent and 0. 05 percent, respectively. Amounts of marginal effect for variables monthly income and education showed that with the increase of one variable mentioned probability of willingness to pay increase 4. 2 percent and 2. 7 percent and for two variables distance to home and proposed price were leading to a reduction in the probability of willingness to pay for visitors 3. 4 percent and 0. 3 percent, respectively. Marginal effect for car owner variable showed that willingness to pay in car owners 15. 5 percent higher than don’ t it. The whole annual recreational value of the region was estimated 1266. 18 million Rials in 2016. Conclusion: The high amount of recreational value represented the beauty and value of the region's and the importance of this region to the visitors, that reveals the need for attention to the management of tourism industry in this area, to prevent the destruction of these valuable ecosystems and maybe income-generating.

Background and objectives: Some forest management, in addition to direct impact on soil, will also affect indirectly soil physical and chemical properties by changing or degrading vegetation cover. Accordingly, forest reserves are most common protection systems in the Iran forest ecosystems management that can affect physio-chemical properties of soil directly or indirectly. Since there are not enough studies to quantity the effects of this type of protection on soil properties in Iran, therefore, this study was one following aim: the effect of short-term protection management on some chemical properties of the soil in Chamhesar Pear forest reserve in Delfan. Thus assessing the impacts of this type of management on the soil can lead managers to continue the process. Materials and Methods: In addition, sampling of soil in the core and buffer zones of the studied area, a region with similar physiographic characteristics was selected outside the reserve (as control). Soil samples were collected on three transects with 250 m length and north-east to south-west direction with a height difference of 40 meters towards the core and buffer zones. Each transect consists of 3 zones: core, buffer and transition zones. Soil samples were collected at intervals of 20 meters on each transect under the crown of the nearest Pears tree at depth of 10 cm. Overall in the three transects, 36 soil samples were taken. Then the normalization of the data was determined by Kolmogorov-Smirnov test; the comparison of the means and multiple comparison of the means was done respectively using one-way ANOVA and Duncan test. Results: The results showed that there was a significant difference between the amounts of organic carbon, total nitrogen, phosphorus, potassium, electrical conductivity, acidity and magnesium of soil in three zones. The highest amount of organic carbon (9. 57%), nitrogen (0. 25%), phosphorus (4. 32 mg / kg), potassium (57. 33 mg / kg) and electrical conductivity (198. 70 μ s/ m) was measured in the soil of core zone and the highest level of acidity and magnesium of soil was 7. 62 and 8. 56 mg/kg respectively, in the transition zone. In the other words, the amount of carbon, nitrogen, phosphorus, potassium and electrical conductivity of soil had increased and level of acidity and magnesium of soil has decreased from the transition zone to core zone. Conclusion: The results of this study showed that protection management had the positive effect on the chemical properties of soil. In fact, protection has been caused to preventing grazing, increasing vegetation cover and decreasing rate of destruction, as a result a significant effect on some chemical properties of soil.