Pub Date : 2023-08-01DOI: 10.37482/0536-1036-2023-4-120-135
A. Makarenko
An improvement of methods and models for preliminary estimation of the performance of harvesters in timber production intends to support better justification of the use of certain harvester types and technologies for specific natural and production conditions. It is possible to increase the accuracy of calculation models with a more complete and realistic description of the production environment and operational processes. The article presents a modelling of the harvester’s movements across cutting areas for selecting a position with the highest number of accessible trees. The investigational process involved the creation of an algorithm along with a simulation model and the statistical processing of the results. The problem-solving process required consideration of the tree’s distribution within the cutting region. The data arrays, which were necessary for efficiency evaluation in the simulation model and its software implementation, were the following: the distance between the working stands of the machine with the maximum number of available trees, the time of cyclic processing, and the number of trees in the area. The results of the statistical analysis of the data are presented with justification from the theoretical laws of probability distribution. The choice of machine working stands, which considered the arrangement of the trees, was estimated using the productivity per hour index. The index was calculated with a constant distance parameter that is equal to the difference between the maximum and the minimum manipulator’s movement, and it was also calculated for a stand with a maximum number of accessible trees. The calculation function for the index involves random variables that characterize the working conditions of the stand. The index itself is conceded as a random variable. The values for it were found by statistical data processing. A comparison of the values determined a high probability of a significant increase in the productivity of the harvester. At the stand with the maximum number of trees, it is estimated at around 8 % with a standard deviation of 0.199. For citation: Makarenko A.V. Effective Positioning in Cutting Area of a Harvester Using Computer Modelling. Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 4, pp. 120–135. (In Russ.). https://doi.org/10.37482/0536-1036-2023-4-120-135
{"title":"Effective Positioning in Cutting Area of a Harvester Using Computer Modelling","authors":"A. Makarenko","doi":"10.37482/0536-1036-2023-4-120-135","DOIUrl":"https://doi.org/10.37482/0536-1036-2023-4-120-135","url":null,"abstract":"An improvement of methods and models for preliminary estimation of the performance of harvesters in timber production intends to support better justification of the use of certain harvester types and technologies for specific natural and production conditions. It is possible to increase the accuracy of calculation models with a more complete and realistic description of the production environment and operational processes. The article presents a modelling of the harvester’s movements across cutting areas for selecting a position with the highest number of accessible trees. The investigational process involved the creation of an algorithm along with a simulation model and the statistical processing of the results. The problem-solving process required consideration of the tree’s distribution within the cutting region. The data arrays, which were necessary for efficiency evaluation in the simulation model and its software implementation, were the following: the distance between the working stands of the machine with the maximum number of available trees, the time of cyclic processing, and the number of trees in the area. The results of the statistical analysis of the data are presented with justification from the theoretical laws of probability distribution. The choice of machine working stands, which considered the arrangement of the trees, was estimated using the productivity per hour index. The index was calculated with a constant distance parameter that is equal to the difference between the maximum and the minimum manipulator’s movement, and it was also calculated for a stand with a maximum number of accessible trees. The calculation function for the index involves random variables that characterize the working conditions of the stand. The index itself is conceded as a random variable. The values for it were found by statistical data processing. A comparison of the values determined a high probability of a significant increase in the productivity of the harvester. At the stand with the maximum number of trees, it is estimated at around 8 % with a standard deviation of 0.199. For citation: Makarenko A.V. Effective Positioning in Cutting Area of a Harvester Using Computer Modelling. Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 4, pp. 120–135. (In Russ.). https://doi.org/10.37482/0536-1036-2023-4-120-135","PeriodicalId":44136,"journal":{"name":"Lesnoy Zhurnal-Forestry Journal","volume":"68 6 1","pages":""},"PeriodicalIF":0.2,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79313969","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-01DOI: 10.37482/0536-1036-2023-4-155-168
A. Shkuro, V. Glukhikh, K. Usova, D. D. Chirkov, P. Zakharov, A. Vurasko
It is anticipated that the creation of wood-polymer composites (WPC) made of naturally renewable polymers and their derivatives (biocomposites) would have a significant practical use due to the rise in prices for synthetic thermoplastic polymers derived from oil and gas. Furthermore, the necessity to replace synthetic polymers such as polyethylene, polypropylene, polyvinyl chloride, and others as components of composite materials is also associated with environmental hazards caused by their low degradation rate in the natural media (soil, water, and air). A further problem for manufacturers of WPC is the legislative requirement for autonomous neutralisation of production waste. One of the potential materials for practical application in the production of WPC are binders based on plasticised cellulose acetates. Russian and foreign scientists have studied the influence of the degree of acetylation of cellulose acetate on the properties of polymeric materials that do not contain lignocellulose fillers. There is no information found concerning the secondary use of cellulose acetate waste for the production of WPC. This article presents the results of an investigation into the hot pressing of biocomposites with a polymer phase of plasticised cellulose acetates of varying degrees of acetylation and fillers: wood flour and waste acetate photographic film. An experimental and statistical dependence of the effect of the degree of acetylation of cellulose acetate and filler content in the biocomposite on its properties was developed, sufficient to exceed a confidence level of 0.9. The experimental specifications included decomposition in activated soil, water absorption, bending strength, Brinell hardness, etc. Some test results showed that the derived biocomposites have the same level of properties as the reference WPC, which consists of a high-density polyethylene phase with a wood flour content of 50 %. The derived dependencies allow us to predict changes in the properties of biocomposites at different degrees of acetylation of plasticised cellulose acetate and filler content. Moreover, they solve the problem of choosing the optimal chemical combination for WPC for manufacturing a specific product by hot pressing. For citation: Shkuro A.E., Glukhikh V.V., Usova K.A., Chirkov D.D., Zakharov P.S., Vurasko A.V. Deriving Biocomposites of Polymer Phase Plasticised Cellulose Acetates with Varying Degrees of Acetylation. Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 4, pp. 155–168. (In Russ.). https://doi.org/10.37482/0536-1036-2023-4-155-168
{"title":"Deriving Biocomposites of Polymer Phase Plasticised Cellulose Acetates with Varying Degrees of Acetylation","authors":"A. Shkuro, V. Glukhikh, K. Usova, D. D. Chirkov, P. Zakharov, A. Vurasko","doi":"10.37482/0536-1036-2023-4-155-168","DOIUrl":"https://doi.org/10.37482/0536-1036-2023-4-155-168","url":null,"abstract":"It is anticipated that the creation of wood-polymer composites (WPC) made of naturally renewable polymers and their derivatives (biocomposites) would have a significant practical use due to the rise in prices for synthetic thermoplastic polymers derived from oil and gas. Furthermore, the necessity to replace synthetic polymers such as polyethylene, polypropylene, polyvinyl chloride, and others as components of composite materials is also associated with environmental hazards caused by their low degradation rate in the natural media (soil, water, and air). A further problem for manufacturers of WPC is the legislative requirement for autonomous neutralisation of production waste. One of the potential materials for practical application in the production of WPC are binders based on plasticised cellulose acetates. Russian and foreign scientists have studied the influence of the degree of acetylation of cellulose acetate on the properties of polymeric materials that do not contain lignocellulose fillers. There is no information found concerning the secondary use of cellulose acetate waste for the production of WPC. This article presents the results of an investigation into the hot pressing of biocomposites with a polymer phase of plasticised cellulose acetates of varying degrees of acetylation and fillers: wood flour and waste acetate photographic film. An experimental and statistical dependence of the effect of the degree of acetylation of cellulose acetate and filler content in the biocomposite on its properties was developed, sufficient to exceed a confidence level of 0.9. The experimental specifications included decomposition in activated soil, water absorption, bending strength, Brinell hardness, etc. Some test results showed that the derived biocomposites have the same level of properties as the reference WPC, which consists of a high-density polyethylene phase with a wood flour content of 50 %. The derived dependencies allow us to predict changes in the properties of biocomposites at different degrees of acetylation of plasticised cellulose acetate and filler content. Moreover, they solve the problem of choosing the optimal chemical combination for WPC for manufacturing a specific product by hot pressing. For citation: Shkuro A.E., Glukhikh V.V., Usova K.A., Chirkov D.D., Zakharov P.S., Vurasko A.V. Deriving Biocomposites of Polymer Phase Plasticised Cellulose Acetates with Varying Degrees of Acetylation. Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 4, pp. 155–168. (In Russ.). https://doi.org/10.37482/0536-1036-2023-4-155-168","PeriodicalId":44136,"journal":{"name":"Lesnoy Zhurnal-Forestry Journal","volume":"37 1","pages":""},"PeriodicalIF":0.2,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81579924","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-01DOI: 10.37482/0536-1036-2023-4-41-57
L. Isaeva, V. Ershov, G. Urbanavichus, E. Borovichev
The purpose of this study was to investigate the history of growth of the introduced species Pinus sibirica Du Tour and Larix sibirica Ledeb. in the Murmansk region and their state in natural areas of preferential protection. The first finds of Siberian cedar in the Arctic region were recorded in 1911, and Siberian larch in 1925. In the 1930s and 1950s–1960s, these kinds of trees were extensively cultivated in the region. Many cedar and larch growth areas are protected as natural monuments of regional significance. Currently, there are eight natural monuments with Siberian cedar growing on the territory of the Murmansk region and seven natural monuments with Siberian larch. The condition of the trees in the territories under preferential protection and the Lapland State Natural Biosphere Reserve was studied in detail. The invasive species occupy a territory of about 70 ha. It was a complete or random enumeration of the trees and undergrowth with measurements of height and diameter. Siberian cedar ranged in height from 0.02 to 18.00 m, whereas Siberian larch was between 0.01 and 18.00 m. Cedar diameters varied from 0.3 to 31.7 cm, whereas larch diameters ranged from 0.4 to 38.3 cm. It is shown that coniferous introduced species are well acclimatized to the natural conditions of the Arctic, which increases the biodiversity of ecosystems and aesthetic perception. Pinus sibirica Du Tour and Larix sibirica Ledeb. fructify in the conditions of the Kola Arctic region that is a sign of a natural regeneration. It is recommended to monitor the conditions of the plantations on a regular basis in order to provide appropriate care. With the inclusion of plots with the growth of the studied species in natural areas of preferential protection, it is necessary to study their condition, location, accessibility, and targeted application. Evaluation of the effectiveness of existing forest management system will allow a more rational approach to the conservation of valuable cedar and larch tree species in the Arctic region. For citation: Isaeva L.G., Ershov V.V., Urbanavichus G.P., Borovichev E.A. Introduced Species of Cedar and Larch in the Climate Conditions of the Kola Arctic Region. Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 4, pp. . 41–57. (In Russ.). https://doi.org/10.37482/0536-1036-2023-4-41-57
{"title":"Introduced Species of Cedar and Larch in the Climate Conditions of the Kola Arctic Region","authors":"L. Isaeva, V. Ershov, G. Urbanavichus, E. Borovichev","doi":"10.37482/0536-1036-2023-4-41-57","DOIUrl":"https://doi.org/10.37482/0536-1036-2023-4-41-57","url":null,"abstract":"The purpose of this study was to investigate the history of growth of the introduced species Pinus sibirica Du Tour and Larix sibirica Ledeb. in the Murmansk region and their state in natural areas of preferential protection. The first finds of Siberian cedar in the Arctic region were recorded in 1911, and Siberian larch in 1925. In the 1930s and 1950s–1960s, these kinds of trees were extensively cultivated in the region. Many cedar and larch growth areas are protected as natural monuments of regional significance. Currently, there are eight natural monuments with Siberian cedar growing on the territory of the Murmansk region and seven natural monuments with Siberian larch. The condition of the trees in the territories under preferential protection and the Lapland State Natural Biosphere Reserve was studied in detail. The invasive species occupy a territory of about 70 ha. It was a complete or random enumeration of the trees and undergrowth with measurements of height and diameter. Siberian cedar ranged in height from 0.02 to 18.00 m, whereas Siberian larch was between 0.01 and 18.00 m. Cedar diameters varied from 0.3 to 31.7 cm, whereas larch diameters ranged from 0.4 to 38.3 cm. It is shown that coniferous introduced species are well acclimatized to the natural conditions of the Arctic, which increases the biodiversity of ecosystems and aesthetic perception. Pinus sibirica Du Tour and Larix sibirica Ledeb. fructify in the conditions of the Kola Arctic region that is a sign of a natural regeneration. It is recommended to monitor the conditions of the plantations on a regular basis in order to provide appropriate care. With the inclusion of plots with the growth of the studied species in natural areas of preferential protection, it is necessary to study their condition, location, accessibility, and targeted application. Evaluation of the effectiveness of existing forest management system will allow a more rational approach to the conservation of valuable cedar and larch tree species in the Arctic region. For citation: Isaeva L.G., Ershov V.V., Urbanavichus G.P., Borovichev E.A. Introduced Species of Cedar and Larch in the Climate Conditions of the Kola Arctic Region. Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 4, pp. . 41–57. (In Russ.). https://doi.org/10.37482/0536-1036-2023-4-41-57","PeriodicalId":44136,"journal":{"name":"Lesnoy Zhurnal-Forestry Journal","volume":"1 1","pages":""},"PeriodicalIF":0.2,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89637238","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-01DOI: 10.37482/0536-1036-2023-4-105-119
A. Koukhta, O. Maksimova, Veronika V. Kuznetsova
The purpose of this study is a comparative analysis of linear and radial increments of Scots pine (Pinus sylvestris L.) as a response to the growing conditions on the coast of the Kandalaksha Bay of the White Sea, as well as an evaluation of the temperature and precipitation influences of the current and previous growing seasons. These were applied to the conventional methods of measurement and data analysis. The dynamics of growth in height and diameter were employed as indicators of the stands' response to habitant conditions. A statistical analysis of the growth rates was performed, which vary depending on habitat type, as well as an assessment of the connection between biometric indicators of the stands and the amount of precipitation and mean temperature. The significant differences in the series of linear increment increases were found as distinctions between biotopes, but they were absent for the radial increment. Therefore, it is possible to monitor the typical behavior of tree diversity independent of the biotope type using radial growth series. This provides the foundation for a long-term retrospective analysis of environmental impact on the stands by using the annual rings of the trees without taking growing conditions into account. Precipitation was determined to be a limiting factor for radial and linear growth throughout the phenophase of internodal growth and early wood formation. Temperature was identified as a limiting factor for radial development only during the stages of late wood formation and resource accumulation for the following growing season. The high sensitivity of linear increases to climatic conditions was revealed, which makes it useful as a criterion for assessing the state of forest ecosystems over short time periods (up to 30 years). However, this, in turn, dictates the impossibility of forming long-term linear increment series, as for radial growth, which is a significant limitation of this method. The choice of linear or radial growth analysis methods is concluded to be determined by the goals of the intended study, i.e., monitoring forest ecosystems under current climate change conditions or long-term paleoclimate analysis. For citation: Koukhta A.E., Maksimova O.V., Kuznetsova V.V. Influence of Climatic Factors on Scots Pine (Pinus sylvestris L.) Growth on the Coast of the Kandalaksha Bay of the White Sea. Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 4, pp. 105–119. (In Russ.). https://doi.org/10.37482/0536-1036-2023-4-105-119
{"title":"Influence of Climatic Factors on Scots Pine (Pinus sylvestris L.) Growth on the Coast of the Kandalaksha Bay of the White Sea","authors":"A. Koukhta, O. Maksimova, Veronika V. Kuznetsova","doi":"10.37482/0536-1036-2023-4-105-119","DOIUrl":"https://doi.org/10.37482/0536-1036-2023-4-105-119","url":null,"abstract":"The purpose of this study is a comparative analysis of linear and radial increments of Scots pine (Pinus sylvestris L.) as a response to the growing conditions on the coast of the Kandalaksha Bay of the White Sea, as well as an evaluation of the temperature and precipitation influences of the current and previous growing seasons. These were applied to the conventional methods of measurement and data analysis. The dynamics of growth in height and diameter were employed as indicators of the stands' response to habitant conditions. A statistical analysis of the growth rates was performed, which vary depending on habitat type, as well as an assessment of the connection between biometric indicators of the stands and the amount of precipitation and mean temperature. The significant differences in the series of linear increment increases were found as distinctions between biotopes, but they were absent for the radial increment. Therefore, it is possible to monitor the typical behavior of tree diversity independent of the biotope type using radial growth series. This provides the foundation for a long-term retrospective analysis of environmental impact on the stands by using the annual rings of the trees without taking growing conditions into account. Precipitation was determined to be a limiting factor for radial and linear growth throughout the phenophase of internodal growth and early wood formation. Temperature was identified as a limiting factor for radial development only during the stages of late wood formation and resource accumulation for the following growing season. The high sensitivity of linear increases to climatic conditions was revealed, which makes it useful as a criterion for assessing the state of forest ecosystems over short time periods (up to 30 years). However, this, in turn, dictates the impossibility of forming long-term linear increment series, as for radial growth, which is a significant limitation of this method. The choice of linear or radial growth analysis methods is concluded to be determined by the goals of the intended study, i.e., monitoring forest ecosystems under current climate change conditions or long-term paleoclimate analysis. For citation: Koukhta A.E., Maksimova O.V., Kuznetsova V.V. Influence of Climatic Factors on Scots Pine (Pinus sylvestris L.) Growth on the Coast of the Kandalaksha Bay of the White Sea. Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 4, pp. 105–119. (In Russ.). https://doi.org/10.37482/0536-1036-2023-4-105-119","PeriodicalId":44136,"journal":{"name":"Lesnoy Zhurnal-Forestry Journal","volume":"1 1","pages":""},"PeriodicalIF":0.2,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89985412","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-01DOI: 10.37482/0536-1036-2023-4-93-104
V. Ostroshenko, L. Ostroshenko
Scots pine (Pinus sylvestris L.) is a potential introduced plant that can be used for reforestation in the southern part of Primorsky Krai. This plant is valuable for water regulation and mountain strengthening. It is widely used in the national economy. However, the growing area of the stands reduces with logging. It is possible to speed up the regeneration process by applying growth stimulants. The purpose of this study is to investigate the impact of natural (Zircon, Ekopin, Ribav-Extra) and synthetic (Krezatzin, Epin-Extra) growth stimulants on seed germination and biometric parameters of annual and biennial Scots pine seedlings (height, root collar diameter, length of root lobes, and biomass). Before cultivation, the seeds were soaked for 1 hour in a solution of KMnO4 (0.5 %) followed by 20 hours in growth stimulant solutions with concentrations 1.4·10–3 ml/l. The control group was presented with seeds without stimulant treatment. The soil germination was controlled on day 15. It was also determined the effectiveness of the stimulants as root top dressing for annual and biennial seedlings. The concentrations of the solutions were 0.2 and 0.1 ml/l with water as a solvent. The referentce group was seedlings without fertilization. Krezatzin, Ribav-Extra, and Ecopin had a significant impact on seed germination (92.7–94.0 %), exceeding the control group by 5.7–7.2 %. Krezatzin, Ribav-Extra, Zircon and Ecopin were most effective for Scots pine seedlings. In the first year of growth, seedling height increased by 20.3–43.5 %, root collar diameter by 22.2–38.9 %, root lobe length by 23.5–52.9 %. In the second year, these indicators exceeded the control group by 18.4–75.5, 2.9–11.8 and 15.0–36.1 %, respectively. The biomass of biennial seedlings increased by 63.7–185.2 % compared to the control group with the use of these stimulants. The solution concentration of 0.1 ml/l was more effective. The biennial seedlings grown using the stimulants as root top dressing according to biometric indicators meet the requirements of the Reforestation Regulations 2020, significantly exceeding the values specified in them. These seedlings can be used for planting woodlands and landscaping in populated areas. For citation: Ostroshenko V.Yu., Ostroshenko L.Yu. Influence of Growth Stimulants on Seed Germination and Seedlings Growth of Scots Pine (Pinus sylvestris L.). Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 4, pp. 93–104. (In Russ.). https://doi.org/10.37482/0536-1036-2023-4-93-104
{"title":"Influence of Growth Stimulants on Seed Germination and Seedlings Growth of Scots Pine (Pinus sylvestris L.)","authors":"V. Ostroshenko, L. Ostroshenko","doi":"10.37482/0536-1036-2023-4-93-104","DOIUrl":"https://doi.org/10.37482/0536-1036-2023-4-93-104","url":null,"abstract":"Scots pine (Pinus sylvestris L.) is a potential introduced plant that can be used for reforestation in the southern part of Primorsky Krai. This plant is valuable for water regulation and mountain strengthening. It is widely used in the national economy. However, the growing area of the stands reduces with logging. It is possible to speed up the regeneration process by applying growth stimulants. The purpose of this study is to investigate the impact of natural (Zircon, Ekopin, Ribav-Extra) and synthetic (Krezatzin, Epin-Extra) growth stimulants on seed germination and biometric parameters of annual and biennial Scots pine seedlings (height, root collar diameter, length of root lobes, and biomass). Before cultivation, the seeds were soaked for 1 hour in a solution of KMnO4 (0.5 %) followed by 20 hours in growth stimulant solutions with concentrations 1.4·10–3 ml/l. The control group was presented with seeds without stimulant treatment. The soil germination was controlled on day 15. It was also determined the effectiveness of the stimulants as root top dressing for annual and biennial seedlings. The concentrations of the solutions were 0.2 and 0.1 ml/l with water as a solvent. The referentce group was seedlings without fertilization. Krezatzin, Ribav-Extra, and Ecopin had a significant impact on seed germination (92.7–94.0 %), exceeding the control group by 5.7–7.2 %. Krezatzin, Ribav-Extra, Zircon and Ecopin were most effective for Scots pine seedlings. In the first year of growth, seedling height increased by 20.3–43.5 %, root collar diameter by 22.2–38.9 %, root lobe length by 23.5–52.9 %. In the second year, these indicators exceeded the control group by 18.4–75.5, 2.9–11.8 and 15.0–36.1 %, respectively. The biomass of biennial seedlings increased by 63.7–185.2 % compared to the control group with the use of these stimulants. The solution concentration of 0.1 ml/l was more effective. The biennial seedlings grown using the stimulants as root top dressing according to biometric indicators meet the requirements of the Reforestation Regulations 2020, significantly exceeding the values specified in them. These seedlings can be used for planting woodlands and landscaping in populated areas. For citation: Ostroshenko V.Yu., Ostroshenko L.Yu. Influence of Growth Stimulants on Seed Germination and Seedlings Growth of Scots Pine (Pinus sylvestris L.). Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 4, pp. 93–104. (In Russ.). https://doi.org/10.37482/0536-1036-2023-4-93-104","PeriodicalId":44136,"journal":{"name":"Lesnoy Zhurnal-Forestry Journal","volume":"92 1","pages":""},"PeriodicalIF":0.2,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88185888","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-01DOI: 10.37482/0536-1036-2023-4-136-145
Gennadiy F. Prokofiev, Oleg L. Kovalenko
One of the major disadvantages of band saws is their low durability. Breakages during the operation are mostly caused by fractures in notches between the blades of the band as a result of the fatigue phenomenon. The strength of the band saw blades is ensured if the assurance coefficient value is greater than the theoretically determined one. The value of the assurance coefficient of 2 is recommended. A schematic limit-amplitude diagram was used to calculate the durability of band saws. A formula for the estimation of the assurance coefficient was derived. It was used for the calculation of the assurance coefficients of the band saw blades manufactured in accordance with GOST 6532–77, which are applicable in dividing band saw machines. The resulting value of the assurance coefficient was 1.44. The value is extremely low for the band saws because it is much lower than required. Band saw blades should be sharpened regularly to ensure a long and reliable service life. It should be made not only to ensure the required sharpness of the blades but also to remove the defective layers in notches caused by fatigue phenomena. In the article, there are more recommendations for improving the durability of the blades of the band saws. The durability of a new type of band saw with curved aerostatic guides and hard alloy blades was evaluated. Its assurance coefficient was 2.4. Therefore, the machine can be operated reliably for a long time without regular treatment of the notches. Consequently, band saws have low durability due to their increased breakdown rate and low wear resistance. Hence, the costs of their purchase and treatment rise. Therefore, the results presented in the article are practically applicable. For citation: Prokofiev G.F., Kovalenko O.L. Fatigue Strength of Band Saws. Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 4, pp. 136–145. (In Russ.). https://doi.org/10.37482/0536-1036-2023-4-136-145
{"title":"Fatigue Strength of Band Saws","authors":"Gennadiy F. Prokofiev, Oleg L. Kovalenko","doi":"10.37482/0536-1036-2023-4-136-145","DOIUrl":"https://doi.org/10.37482/0536-1036-2023-4-136-145","url":null,"abstract":"One of the major disadvantages of band saws is their low durability. Breakages during the operation are mostly caused by fractures in notches between the blades of the band as a result of the fatigue phenomenon. The strength of the band saw blades is ensured if the assurance coefficient value is greater than the theoretically determined one. The value of the assurance coefficient of 2 is recommended. A schematic limit-amplitude diagram was used to calculate the durability of band saws. A formula for the estimation of the assurance coefficient was derived. It was used for the calculation of the assurance coefficients of the band saw blades manufactured in accordance with GOST 6532–77, which are applicable in dividing band saw machines. The resulting value of the assurance coefficient was 1.44. The value is extremely low for the band saws because it is much lower than required. Band saw blades should be sharpened regularly to ensure a long and reliable service life. It should be made not only to ensure the required sharpness of the blades but also to remove the defective layers in notches caused by fatigue phenomena. In the article, there are more recommendations for improving the durability of the blades of the band saws. The durability of a new type of band saw with curved aerostatic guides and hard alloy blades was evaluated. Its assurance coefficient was 2.4. Therefore, the machine can be operated reliably for a long time without regular treatment of the notches. Consequently, band saws have low durability due to their increased breakdown rate and low wear resistance. Hence, the costs of their purchase and treatment rise. Therefore, the results presented in the article are practically applicable. For citation: Prokofiev G.F., Kovalenko O.L. Fatigue Strength of Band Saws. Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 4, pp. 136–145. (In Russ.). https://doi.org/10.37482/0536-1036-2023-4-136-145","PeriodicalId":44136,"journal":{"name":"Lesnoy Zhurnal-Forestry Journal","volume":"44 1","pages":""},"PeriodicalIF":0.2,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82824900","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-01DOI: 10.37482/0536-1036-2023-4-146-154
V. Melekhov, I. Solovev
The efficiency of a stationary circular saw is determined by the performance and operational reliability of the woodcutting unit. During operation, the circular saw blade is exposed to a variety of complex loads and thermal conditions. The rigidity and stability of the saw blade determine its capacity to resist the perturbing cutting forces. The cutting compound itself is a thin disc made of steel with a hole in the middle that has a serrated cutting edge. It consists of three areas: peripheral, middle, and central. The stability of the saw blade is determined by the middle and peripheral parts. The increase in durability is achieved by plastic deformation to form the strip boundaries of the radial sections. These parts are treated by forging in both national and international practice. Normalization of loads on the blade in case of local mechanical contact with the working body is formed in the strip boundaries of the radial sections through the formation of places with plastic deformation of the metal, which rearrange the loads and place them in the radial direction. At the same time, countertension appears from the adjoining sections, leading to mutual “repulsion” of them and the creation of compressive tension that compensates for the forces of centrifugal acceleration, thermal heating of separate areas of the saw blade, external longitudinal and transverse bending tension that arise during wood processing. The combined interaction of all adjoining sections provides the tension and stability of the saw blade. The creation of the radial sections by forging has some significant disadvantages. Their elimination requires a fundamentally new approach, such as the formation of the residual stress sections in the saw blade by thermal exposure. It creates a normalized residual thermoplastic tension in the saw blade by a short-time (1–2 s) focused thermal influence on the strip boundaries of the radial sections. The results of the conducted research determined the boundaries of the sections for thermal treatment and the temperature range, which ensure the formation of normalized residual thermoplastic tension in the circular saw blade through concentrated pulsed heating of the strip edges of radial sections. For citation: Melekhov V.I., Solovev I.I. Formation of Sectoral Residual Thermoplastic Tension Fields in Circular Saw Blade. Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 4, pp. 146–154. (In Russ.). https://doi.org/10.37482/0536-1036-2023-4-146-154
固定式圆锯的效率取决于木材切割装置的性能和运行可靠性。在运行过程中，圆锯片暴露在各种复杂的负载和热条件下。锯片的刚度和稳定性决定了其抵抗扰动切削力的能力。切割化合物本身是一个薄的圆盘，由钢制成，中间有一个孔，切割边缘呈锯齿状。它由三个区域组成:外围、中部和中心。锯片的稳定性是由中间和外围部件决定的。耐久性的增加是通过塑性变形来形成径向截面的条形边界来实现的。这些零件在国内和国际惯例中都采用锻造处理。在径向截面的条形边界上，通过形成金属塑性变形的地方，使载荷重新排列并置于径向上，从而形成叶片与工作体局部机械接触时载荷的归一化。与此同时，相邻部分出现反张力，导致它们之间的相互“排斥”，并产生压缩张力，以补偿离心加速度的力量，锯片单独区域的热加热，木材加工过程中产生的外部纵向和横向弯曲张力。所有相邻部分的联合相互作用提供了锯片的张力和稳定性。通过锻造制造径向截面有一些明显的缺点。它们的消除需要一种全新的方法，例如通过热暴露在锯片中形成残余应力部分。它通过对径向截面的条形边界的短时间(1-2秒)集中热影响，在锯片中产生归一化残余热塑性张力。研究结果确定了热处理截面的边界和温度范围，通过对径向截面的条形边缘进行集中脉冲加热，保证了圆锯片内形成归一化残余热塑性张力。引证:Melekhov V.I.， Solovev . i .。圆锯片中扇形残余热塑性张力场的形成。俄罗斯林业杂志，2023年第1期。4，第146-154页。(俄国人)。https://doi.org/10.37482/0536-1036-2023-4-146-154
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Pub Date : 2023-08-01DOI: 10.37482/0536-1036-2023-4-202-214
S. Konshakova, N. A. Bulkhov, A. Zaikin, S. Kuznetsov, V. Sivakov
The high level of power supply and technical provision of logging, along with advanced technologies, ensure the enterprise’s competitiveness. The current state of facilities and resources at forestry institutions in the regions is, as a rule, unsatisfactory. Significant engineering and technological backwardness of facilities and resources is due to the specifics of the modern structure of the forest sector. With the purpose of ensuring the production effectiveness of forestry institutions in the regions on the basis of increasing the level of power supply and technical provision for logging, it is necessary to carry out appropriate research. The methods for assessing the forest as an ecosystem are a relevant area of theoretical and applied research. There are 3 basic methods used in world and Russian practice in the assessment of natural resources: comparative, cost, and income. The methodology of cost estimate for natural resources provides a flexible system of indices, which allow assessing natural resources depending on the amount of available information and practical purposes. In terms of spatial economics we propose to develop a pilot project to improve the efficiency of production in the state autonomous forestry institutions of the Republic of Bashkortostan. The project is intended to provide practical guidance on the allocation of 2–3 groups of forestry institutions. We used an expert approach to assess the rating of forestries. Our earlier estimates for forestry enterprises in the Republic of Bashkortostan (state autonomous institutions) were used as the basis for it. The values of quantitative criteria include expert estimates and statistical information from numerous sources, such as reports, handbooks, results of surveys, interviews, etc. The criteria were divided into 2 groups: quantitative (availability of logging equipment, transport accessibility, calculated logging area) and qualitative (state of the logging equipment, repair depot, and management structure). According to the results of the integral assessment, the forestries are divided into 4 groups. Based on the assessment performed, it is advisable to identify the points of growth in the pilot project of modernization the facilities and resources of forestry enterprises. For citation: Konshakova S.A., Bulkhov N.A., Zaikin A.N., Kuznetsov S.G., Sivakov V.V. Assessment of the Development Potential of Forestry Enterprises of the Republic of Bashkortostan. Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 4, pp. 202–214. (In Russ.). https://doi.org/10.37482/0536-1036-2023-4-202-214
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Pub Date : 2023-08-01DOI: 10.37482/0536-1036-2023-4-190-201
Evgeniy М. Tsarev, K. Rukomojnikov, S. Anisimov, Тatyana А. Konyukhova, Аndrey V. Krenev
This article covers concerns about the elimination of low-value deciduous trees by chemical treatment in favour of conifers. Various methods for removing undesirable vegetation are discussed with an indication of their advantages and disadvantages. Central attention is given to the use of arboricides for the treatment of young growth. It is considered that the chemicals must selectively affect the unfavourable plants, avoid any influence on economically valuable species, and be safe for human health and forest fauna. A practically common method of chemical maintenance was investigated, which includes the injection of arboricides into notches on tree trunks. The authors suggest devices confirmed by the patents of the Russian Federation that are suitable for this purpose. The operational principle is the drilling of the notches with the subsequent injection of arboricide. The proposed mechanical treatment increases productivity by decreasing the complexity of the procedure as well as the physical load on the operator during handling and moving of the equipment. The investigational results are compared with the properties of the Cobra apparatus, which was widely used in the Soviet Union and later in the Russian Federation. The research was performed in young stands of Kokshaysky Forest and Shulkinskoe Forestry in the Republic of Mari El. The comparative results of ecological and silvicultural monitoring on coniferous conditions after chemical treatment revealed the higher performance of the proposed device over the Cobra apparatus. The material in this article is recommended to forestry operators as a guide for chemical maintenance, mainly in young stands. For citation: Tsarev E.М., Rukomojnikov K.P., Anisimov S.E., Konyukhova Т.А., Krenev А.V. Improving Chemical Maintenance Techniques in Forest Plantations. Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 4, pp. 190–201. (In Russ.). https://doi.org/10.37482/0536-1036-2023-4-190-201
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Pub Date : 2023-07-07DOI: 10.17073/1609-3577-2023-2-122-136
A. Pashkevich, A. Fedotov, E. N. Poddenezhny, L. Bliznyuk, V. Khovaylo, V. Fedotova, A. A. Kharchanko
The paper studies the thermal, electrical and thermoelectric properties of ZnO–MexOy ceramics with 1 ≤ x, y ≤ 3, where Me = Al, Co, Fe, Ni, Ti. The samples were made on the basis of ceramic sintering technology of powder mixtures of two or more oxides in an open atmosphere with variations in temperature and duration of annealing. Structural and phase studies of ceramics indicate that the addition of powders of MexOy alloying agents to ZnO powder with a wurtzite structure after the synthesis process leads to the release of secondary phases such as Znx(Me)yO4 spinels and a 4-fold increase in the porosity of the resulting ceramics. Studies of thermal conductivity at room temperature indicate the predominance of the lattice contribution. The decrease in thermal conductivity during doping is due to an increase in phonon scattering due to the influence of the following factors: (1) the size factor when replacing zinc ions in the ZnO (wurtzite) crystal lattice with metal ions from the added MexOy oxides; (2) the formation of defects – point, grain boundaries (microstructure grinding); (3) increase in porosity (decrease in density); and (4) formation of additional phase particles (such as spinels Znx(Mе)yO4). The effect of these factors in the substitution of zinc ions with metals (Co, Al, Ti, Ni, Fe) leads to an increase in the thermoelectric Q-factor of ZT by 4 orders of magnitude (due to a decrease in electrical resistivity and thermal conductivity with a relatively small decrease in the coefficient of thermal EMF). The reason for the decrease in electrical resistance is the more uniform redistribution of alloying metal ions in the wurtzite lattice, resulting in an increase in the number of donor centers, formed with an increase in the duration of annealing.
{"title":"Thermal and thermoelectric properties of zinc oxide ceramics alloyed with metals","authors":"A. Pashkevich, A. Fedotov, E. N. Poddenezhny, L. Bliznyuk, V. Khovaylo, V. Fedotova, A. A. Kharchanko","doi":"10.17073/1609-3577-2023-2-122-136","DOIUrl":"https://doi.org/10.17073/1609-3577-2023-2-122-136","url":null,"abstract":"The paper studies the thermal, electrical and thermoelectric properties of ZnO–MexOy ceramics with 1 ≤ x, y ≤ 3, where Me = Al, Co, Fe, Ni, Ti. The samples were made on the basis of ceramic sintering technology of powder mixtures of two or more oxides in an open atmosphere with variations in temperature and duration of annealing. Structural and phase studies of ceramics indicate that the addition of powders of MexOy alloying agents to ZnO powder with a wurtzite structure after the synthesis process leads to the release of secondary phases such as Znx(Me)yO4 spinels and a 4-fold increase in the porosity of the resulting ceramics. Studies of thermal conductivity at room temperature indicate the predominance of the lattice contribution. The decrease in thermal conductivity during doping is due to an increase in phonon scattering due to the influence of the following factors: (1) the size factor when replacing zinc ions in the ZnO (wurtzite) crystal lattice with metal ions from the added MexOy oxides; (2) the formation of defects – point, grain boundaries (microstructure grinding); (3) increase in porosity (decrease in density); and (4) formation of additional phase particles (such as spinels Znx(Mе)yO4). The effect of these factors in the substitution of zinc ions with metals (Co, Al, Ti, Ni, Fe) leads to an increase in the thermoelectric Q-factor of ZT by 4 orders of magnitude (due to a decrease in electrical resistivity and thermal conductivity with a relatively small decrease in the coefficient of thermal EMF). The reason for the decrease in electrical resistance is the more uniform redistribution of alloying metal ions in the wurtzite lattice, resulting in an increase in the number of donor centers, formed with an increase in the duration of annealing.","PeriodicalId":44136,"journal":{"name":"Lesnoy Zhurnal-Forestry Journal","volume":"109 1","pages":""},"PeriodicalIF":0.2,"publicationDate":"2023-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77268566","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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