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The history of the creation of electroadhesive joints 电粘合接头的发明历史
Forestry Bulletin Pub Date : 2023-02-01 DOI: 10.18698/2542-1468-2023-1-107-113
Y. Evdokimov, V. Sulimenko, A. Meshcheryakov, D.V. Russkikh
{"title":"The history of the creation of electroadhesive joints","authors":"Y. Evdokimov, V. Sulimenko, A. Meshcheryakov, D.V. Russkikh","doi":"10.18698/2542-1468-2023-1-107-113","DOIUrl":"https://doi.org/10.18698/2542-1468-2023-1-107-113","url":null,"abstract":"The history of the first electroadhesive joints, their features, physical-chemical and other characteristics are considered. A significant contribution to the development of these directions of science and technology of Soviet (Russian) scientists is shown.","PeriodicalId":12343,"journal":{"name":"Forestry Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77583336","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}
引用次数: 0
Root-closed forest ecosystem formation above forest boundary in Northern Urals mountains 乌拉尔北部山区林界以上根闭林生态系统的形成
Forestry Bulletin Pub Date : 2023-02-01 DOI: 10.18698/2542-1468-2023-1-26-34
N. Tantsyrev, N. Ivanova, I. Petrova
{"title":"Root-closed forest ecosystem formation above forest boundary in Northern Urals mountains","authors":"N. Tantsyrev, N. Ivanova, I. Petrova","doi":"10.18698/2542-1468-2023-1-26-34","DOIUrl":"https://doi.org/10.18698/2542-1468-2023-1-26-34","url":null,"abstract":"The purpose of this work is to determine the length of the root systems of Siberian stone pine undergrowth (Pinus sibirica Du Tour) growing in the mountain tundra of the Northern Urals and to establish regression relationships with its aboveground parameters and age. The studies were carried out in the belt of mountain stony shrub-moss-lichen tundra at an altitude of 1010–1040 m above sea level on the plateau of the «Tri Bugra» mountain massif (59°30ʹ N, 59°15ʹ E). Consideration of environmental conditions and undergrowth of woody plants was carried out on 30 registered plots with a size of 5×5 m. P. sibirica is absolutely dominant (6,0 thousand specimens per ha) in the undergrowth. Its constant almost annual renewal began in the end 60s XX century. It was revealed that under the conditions of mountain tundra, the length of the root systems of all studied age groups of P. sibirica undergrowth exceeds its height by 1,2…1,5 times, and the area of soil nutrition (field of root competition) exceeds the area of projective crown cover by more than 10 times. A statistically significant relationship between the length of roots and the age (R2 = 0,78) of the undergrowth and its height (R2 = 0,92) are established. Regression equations are obtained. At the current rates of climate warming and the growth of P. sibirica trees, the revealed dependences make it possible to predict for the mountain tundra of the Northern Urals mosaic formation of primary underground-closed forest associations (woodlands) with characteristic forest relationships in 20–25 years, and communities with multiple interweaving of root systems in 40–50 years.","PeriodicalId":12343,"journal":{"name":"Forestry Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89484760","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}
引用次数: 0
White сedar growth in the N.V. Tsitsin Main Botanical Garden arboretum of Russian Academy Of Sciences according to dendrochronological analysis 根据树木年代学分析,俄罗斯科学院齐辛主要植物园白桦的生长情况
Forestry Bulletin Pub Date : 2023-02-01 DOI: 10.18698/2542-1468-2023-1-5-16
D. Rumyantsev, S. L. Rysin, A. A. Kozhenkova, P.S. Aleksandrov, N.S. Vorob’eva, A. Epishkov
{"title":"White сedar growth in the N.V. Tsitsin Main Botanical Garden arboretum of Russian Academy Of Sciences according to dendrochronological analysis","authors":"D. Rumyantsev, S. L. Rysin, A. A. Kozhenkova, P.S. Aleksandrov, N.S. Vorob’eva, A. Epishkov","doi":"10.18698/2542-1468-2023-1-5-16","DOIUrl":"https://doi.org/10.18698/2542-1468-2023-1-5-16","url":null,"abstract":"The study materials of the White сedar (Thuja occidentalis L.) radial growth (the width of the annual ring) variability in the N.V. Tsitsin Main Botanical Garden arboretum of the Russian Academy of Sciences are presented. The main patterns of short-term and long-term variability of radial growth are established, the influence peculiarities of meteorological parameters on the growth figures are revealed, a yield table of tree growth by trunk diameter is compiled. Based on the results of dendroclimatic analysis, recommendations for the care of plants are given. The results of dendroclimatic analysis were compared with the results of similar studies of White Cedar growth in the Mytishchi branch of the Bauman Moscow State Technical University arboretum.","PeriodicalId":12343,"journal":{"name":"Forestry Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76054388","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}
引用次数: 0
Hydrophobization of cellulose spathellas obtained from Sosnowsky hogweed stem with solutions of tetrafluoroethylene telomers 四氟乙烯端粒溶液对猪草茎纤维素的疏水性研究
Forestry Bulletin Pub Date : 2023-02-01 DOI: 10.18698/2542-1468-2023-1-95-106
S. A. Baskakov, Y. V. Baskakova, E. N. Kabachkov, G. Kichigina, P. P. Kushch, D. Kiryukhin, S. S. Krasnikova, E. Badamshina, T. A. Soldatenkov, V. N. Vasilets, F. Milovich, Y. Shulga
{"title":"Hydrophobization of cellulose spathellas obtained from Sosnowsky hogweed stem with solutions of tetrafluoroethylene telomers","authors":"S. A. Baskakov, Y. V. Baskakova, E. N. Kabachkov, G. Kichigina, P. P. Kushch, D. Kiryukhin, S. S. Krasnikova, E. Badamshina, T. A. Soldatenkov, V. N. Vasilets, F. Milovich, Y. Shulga","doi":"10.18698/2542-1468-2023-1-95-106","DOIUrl":"https://doi.org/10.18698/2542-1468-2023-1-95-106","url":null,"abstract":"The process of obtaining cellulose from the Sosnowsky hogweed stem and spathellas from this cellulose is described in detail. The task is relevant from the point of view of the use of this weed. The elemental composition and properties of the obtained cellulose samples were studied by elemental analysis, infrared (IR) spectroscopy, X-ray powder diffractometry, differential scanning calorimetry (DSC), and X-ray photoelectron spectroscopy (XPS). The study of IR spectra and X-ray patterns of cellulose made it possible to determine the degree of its crystallinity (65…75 %). The glass transition temperature (105…108 °C) of the samples was estimated from the results of DSC. A comparative analysis of the characteristics of the obtained cellulose with the available literature data was carried out. The treatment of spathellas obtained from cellulose with solutions of radiation-synthesized tetrafluoroethylene (TFE) telomers made it possible to obtain a hydrophobic material with a contact angle exceeding 140°. For hydrophobization, we used TFE telomers synthesized in acetone, the binary solvent Freon 113 + ammonia, and Flutec PP3, which have different terminal groups. It has been established that the interfacial angle of the surface of a cellulose spathella treated with telomers depends both on the composition (end groups) of the telomer and on the initial concentration of TFE at which the synthesis was carried out. The optimal concentration of TFE for the synthesis of telomers in Flutec PP3 has been determined. The presence of a fluoropolymer coating of the spathella, which ensures its hydrophobicity, was confirmed by XPS results.","PeriodicalId":12343,"journal":{"name":"Forestry Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83220719","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}
引用次数: 0
Frequency determination of band saw teeth grinding (regrinding) 带锯片磨(再磨)频率测定
Forestry Bulletin Pub Date : 2023-02-01 DOI: 10.18698/2542-1468-2023-1-134-138
G. Prokof’ev, O. Kovalenko
{"title":"Frequency determination of band saw teeth grinding (regrinding)","authors":"G. Prokof’ev, O. Kovalenko","doi":"10.18698/2542-1468-2023-1-134-138","DOIUrl":"https://doi.org/10.18698/2542-1468-2023-1-134-138","url":null,"abstract":"The advantages and disadvantages of band saws in comparison with other sawmills are considered. The necessity of timely grinding (regrinding) of band saws during their operation is emphasized. A method for calculating the time between regrindings of a band saw is proposed, which ensures the required service life of the saw - the time between regrindings of a band saw is determined taking into account the value of the limited endurance of the saw, determined for a given safety factor; the required quality of the lumber output and the reduction of energy consumption - the time between regrinding of the band saw is determined taking into account the amount of blunting of the band saw teeth, characterized by the radius of curvature of their main cutting edge. It is noted that of the two obtained values of the time between saw regrindings, it is necessary to take the smallest value. It is recommended to use the method proposed in the article when calculating the modes of sawing wood on separating and log band saw machines.","PeriodicalId":12343,"journal":{"name":"Forestry Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76184355","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}
引用次数: 0
Technology development for determining tree species using computer vision 利用计算机视觉确定树种的技术进展
Forestry Bulletin Pub Date : 2023-02-01 DOI: 10.18698/2542-1468-2023-1-60-66
D.Y. Voytov, S. B. Vasil’ev, D. V. Kormilitsyn
{"title":"Technology development for determining tree species using computer vision","authors":"D.Y. Voytov, S. B. Vasil’ev, D. V. Kormilitsyn","doi":"10.18698/2542-1468-2023-1-60-66","DOIUrl":"https://doi.org/10.18698/2542-1468-2023-1-60-66","url":null,"abstract":"A technology has been developed to determine the European white birch (Betula pendula Roth.) species in the photo. The differences of the known neural networks of classifiers with the definition of objects are studied. YOLOv4 was chosen as the most promising for further development of the technology. The mechanism of image markup for the formation of training examples has been studied. The method of marking on the image has been formed. Two different datasets have been formed to retrain the network. An algorithmic increase in the dataset was carried out by transforming images and applying filters. The difference in the results of the classifier is determined. The accuracy when training exclusively on images containing hanging birch was 35 %, the accuracy when training on a dataset containing other trees was 71 %, the accuracy when training on the entire dataset was 75 %. To demonstrate the work, birch trees were identified in photographs taken in the arboretum of the MF Bauman Moscow State Technical University. To improve the technology, additional training is recommended to determine the remaining tree species. The technology can be used for the implementation of taxation of specific tree species; the formation of marked datasets for further development; the primary element in the tree image analysis system, to exclude third-party objects in the original image.","PeriodicalId":12343,"journal":{"name":"Forestry Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84291213","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}
引用次数: 0
Development of filter-sorbing materials for modern gas masks and respirators 现代防毒面具和呼吸器用过滤-吸附材料的研制
Forestry Bulletin Pub Date : 2023-02-01 DOI: 10.18698/2542-1468-2023-1-121-133
M.V. Talipova, A.V. Lyang, N. V. Shcherbak
{"title":"Development of filter-sorbing materials for modern gas masks and respirators","authors":"M.V. Talipova, A.V. Lyang, N. V. Shcherbak","doi":"10.18698/2542-1468-2023-1-121-133","DOIUrl":"https://doi.org/10.18698/2542-1468-2023-1-121-133","url":null,"abstract":"The article focuses on the study of filter-sorbing materials (FSM) for the development of small-sized filters and the formation of a modern filters range for gas masks and respirators. There are various kinds of filters, namely particle filters, consisting of a filter material (FM) with protection from aerosols; gas filters, consisting of coal charge with protection from various concentrations of dangerous gases and vapors and combined filters, including anti-aerosol and gas protection. But in industry, due to the improvement of working conditions at enterprises, personal respiratory protection equipment is needed both from aerosols and from low concentrations of dangerous gases and vapors in the air of the working area. The creation of a new small-sized filter with a single filter-sorbing element with low resistance to air flow during breathing is an actual task. In order to form an assortment of modern filters for gas masks and respirators, we studied FSM in the form of polymer or glass fibers sprayed with carbon particles. An experimental series of studies based on the use of FSMs with adsorbents has been carried out, activated carbon (AC) and various absorbers were obtained by impregnation of AC. It is determined that the impregnation of AC with special additives allows for additional protection from inorganic and acid gases and vapors, from ammonia. Comparative tests of the FSMs were carried out with the analysis of the research results. Optimal FSMs have been determined. The fractional composition of coal particles is determined depending on the method of their application. The sorption properties of the obtained FSMs are determined. In this work, for the first time, the combination of a filter material with AC impregnated with chemical additives in particle filters was tested and evaluated. The effect of a combination of AC and a fibrous semi-finished product on the properties of FSM has been studied.","PeriodicalId":12343,"journal":{"name":"Forestry Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91331366","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}
引用次数: 0
Plant communities ground cover digression of recreational sites in Valday National Park 瓦尔代国家公园休闲场所的植物群落、地被覆盖离场
Forestry Bulletin Pub Date : 2023-02-01 DOI: 10.18698/2542-1468-2023-1-35-44
O.S. Terent’eva, E. Rokhlova, I.G. Khmel’shchikova
{"title":"Plant communities ground cover digression of recreational sites in Valday National Park","authors":"O.S. Terent’eva, E. Rokhlova, I.G. Khmel’shchikova","doi":"10.18698/2542-1468-2023-1-35-44","DOIUrl":"https://doi.org/10.18698/2542-1468-2023-1-35-44","url":null,"abstract":"The article presents the results of a study of the influence of recreational pressure on the ground cover of forest communities in the Valday National Park. The comparison of trial plots with different degrees of recreational pressure in terms of species composition, abundance of species and the ratio of ecological cenotic groups of plants is given. The bioindicator species of recreational digression were identified in the studied areas. The most resistant species of herbaceous plants (anthropotollerants) (Plantago major L., Poa annua L.) were identified on the taste areas. The stages of recreational digression on the tasted areas were determined. The main factors of anthropogenic impact оn the ground cover are presented. The dependence of the species composition of the ground cover on the сrown density was identified. The options of conservation of the ground cover were suggested. The recommendations for the restoration of plant communities of recreational areas with a high stage of digression were given.","PeriodicalId":12343,"journal":{"name":"Forestry Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90806562","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}
引用次数: 0
Application efficiency of «Azorro, KS» fungicide in growing common oak seedlings in open and protected ground 杀菌剂Azorro, KS在开阔保护地普通栎树育苗中的应用效果
Forestry Bulletin Pub Date : 2023-02-01 DOI: 10.18698/2542-1468-2023-1-53-59
I. Taziev, A. Mukhametshina, G. A. Petrova, N.M. Tazmeev
{"title":"Application efficiency of «Azorro, KS» fungicide in growing common oak seedlings in open and protected ground","authors":"I. Taziev, A. Mukhametshina, G. A. Petrova, N.M. Tazmeev","doi":"10.18698/2542-1468-2023-1-53-59","DOIUrl":"https://doi.org/10.18698/2542-1468-2023-1-53-59","url":null,"abstract":"Nowadays the problem of oak forests degradation is topical today in the Republic of Tatarstan, where large woods are formed and are considered to be the most valuable. The area of oak plantations decreases every year due to damage caused by frosts in 1978–1979, therefore, with the oak dying, the areas of aspen, linden and birch plantations increase. The oak forests regeneration is connected with the cultivation of healthy planting material in the nurseries of the region. The article is devoted to the study of the fungicide «Azorro, KS» efficiency in the cultivation of common oak seedlings in open and protected ground conditions. The research was carried out at the experimental site of the Faculty of Forestry and Ecology of the Kazan State Agrarian University. In the course of the research, a phytopathological analysis of acorns was carried out, the degree of infection with pests and diseases, safety by the end of the growing season was determined; biometric indicators of common oak seedlings were measured. The following types of fungi have been found such as Penicillium, Mucor and Rhizopus. The positive effect of the drug used on the growth and development of seedlings in open and protected ground was noted. The highest common oak seedlings were noted in protected ground using a fungicide — 21,0 cm, in open ground the average height was 11,0 cm. The preparation showed its highest efficiency in protected ground — 92 %. High efficiency in the open ground after the third treatment was 90 %. The safety of common oak seedlings by the end of the growing season in protected ground conditions varied from 96,9 to 97,1 %.","PeriodicalId":12343,"journal":{"name":"Forestry Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76667924","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}
引用次数: 0
Chemical and biological degradation of phytogenic protein components 植物性蛋白质成分的化学和生物降解
Forestry Bulletin Pub Date : 2023-02-01 DOI: 10.18698/2542-1468-2023-1-85-94
A. Ivankin
{"title":"Chemical and biological degradation of phytogenic protein components","authors":"A. Ivankin","doi":"10.18698/2542-1468-2023-1-85-94","DOIUrl":"https://doi.org/10.18698/2542-1468-2023-1-85-94","url":null,"abstract":"Proteins in the form of biopolymer compounds are the basic components of all objects of natural origin. Hydrolysis of the protein components of plant materials is the main mechanism of biochemical degradation of biomass in nature. The article presents a comparative analysis of data on the composition of protein-bound and free amino acids of objects of plant and other origin. The purpose of the work was to consider the possibility of transformation of protein systems under the influence of enzymes and chemical reagents, leading to the sequential breakdown of protein macrocomplexes to peptides and further to free amino acids. A method of acid hydrolysis of hard protein raw materials is described, which allows almost completely, with a yield of more than 95 %, to degrade the protein structure at a temperature of 105 °C and a hydromodulus of 1:4 in the presence of a 6M solution of hydrochloric or sulfuric acids for 24 hours. the composition of the resulting acid hydrolysates. The possibility of chemical degradation of protein structures in the presence of weak organic acids such as lactic and citric acids is discussed. It has been shown that the resulting product in this case may contain up to a third of free amino acids, as well as 25...35 % of short peptides. Disadvantages of chemical degradation of protein structures due to the possible racemization of free amino acids released during protein hydrolysis in the presence of strong mineral acids and bases are discussed. The possibilities of biochemical defragmentation of plant proteins under the influence of enzymes are discussed. It has been shown that the enzymatic processing of proteins can be carried out with an efficiency of 65...85 % at low temperatures of 30...50 °C for 4...6 h with an enzyme-substrate ratio of 1:10 to 1:100, depending on the activity of the enzyme type and its hydrolase activity. The article presents a brief overview of the features of obtaining protein hydrolysates and compares the kinetics of protein hydrolysis under the influence of enzyme systems, as well as mineral and organic acids. It is concluded that the chemical and biodegradation of plant protein raw materials is promising for obtaining useful components of nutritional systems.","PeriodicalId":12343,"journal":{"name":"Forestry Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84853476","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}
引用次数: 0
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