Pub Date : 2021-12-23DOI: 10.26614/les-wood.2021.v70n02a07
Luka Goropečnik, Rafael Šenk, Matija Jošt, Katarina Čufar, Jože Kropivšek
Z industrijo 4.0 vstopamo v digitalno dobo, kjer se bodo tudi v lesnopredelovalnih podjetjih bistveno spremenile zahteve po znanjih in kompetencah zaposlenih. To vpliva tudi na izobraževanje na področju lesarstva. Cilj raziskave je bil ugotoviti, kateri načini poučevanja in učenja najbolj motivirajo predstavnike generacij Y in Z, na različnih nivojih izobraževanja (od poklicnega izobraževanja do magistrskega študijskega programa) v lesarstvu, kakšen način izvedbe izobraževanja je zanje najprimernejši in kaj menijo o študiju na daljavo. V ta namen smo izvedli anketiranje s pomočjo družabnih omrežij in e-učilnice. Rezultati so pokazali, da anketirane najbolj motivira okolje, naravnano k razvoju, je varno in stabilno ter delo v delovni skupini, medtem ko si ne želijo tekmovalnega okolja. Med skupinami na različnih ravneh in načinih izobraževanja (redno, vseživljenjsko) nismo opazili večjih razlik v motivacijskih dejavnikih. Sicer pa glavno motivacijo učečih se v lesarstvu ne glede na generacijo predstavljajo notranje spodbude posameznika, medtem ko se zunanje spodbude med generacijami bolj razlikujejo.
{"title":"Motivacija za izobraževanje in usposabljanje generacij Y in Z v lesarstvu","authors":"Luka Goropečnik, Rafael Šenk, Matija Jošt, Katarina Čufar, Jože Kropivšek","doi":"10.26614/les-wood.2021.v70n02a07","DOIUrl":"https://doi.org/10.26614/les-wood.2021.v70n02a07","url":null,"abstract":"Z industrijo 4.0 vstopamo v digitalno dobo, kjer se bodo tudi v lesnopredelovalnih podjetjih bistveno spremenile zahteve po znanjih in kompetencah zaposlenih. To vpliva tudi na izobraževanje na področju lesarstva. Cilj raziskave je bil ugotoviti, kateri načini poučevanja in učenja najbolj motivirajo predstavnike generacij Y in Z, na različnih nivojih izobraževanja (od poklicnega izobraževanja do magistrskega študijskega programa) v lesarstvu, kakšen način izvedbe izobraževanja je zanje najprimernejši in kaj menijo o študiju na daljavo. V ta namen smo izvedli anketiranje s pomočjo družabnih omrežij in e-učilnice. Rezultati so pokazali, da anketirane najbolj motivira okolje, naravnano k razvoju, je varno in stabilno ter delo v delovni skupini, medtem ko si ne želijo tekmovalnega okolja. Med skupinami na različnih ravneh in načinih izobraževanja (redno, vseživljenjsko) nismo opazili večjih razlik v motivacijskih dejavnikih. Sicer pa glavno motivacijo učečih se v lesarstvu ne glede na generacijo predstavljajo notranje spodbude posameznika, medtem ko se zunanje spodbude med generacijami bolj razlikujejo.","PeriodicalId":52851,"journal":{"name":"Les","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45825639","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 : 2021-11-14DOI: 10.26614/les-wood.2021.v70n02a03
Saurav Nepal, R. Wimmer, V. Zelinski
Gross and net calorific value of 13 samples of Eucalyptus nitens wood were determined at HAWK (Hochschule für Angewandte Wissenschaft und Kunst), Göttingen, Germany. Among 13 samples, 12 were thermally modified and one was unmodified. Calorific values of samples were determined by using a bomb calorimeter, and the wood components (cellulose, hemicellulose, lignin, and extractives) already analysed by Wentzel et al. (2019). After determination of the values, samples were statistically analysed by R studio to find the relations among the calorific value, temperature, and wood components. The gross calorific value and net calorific value of the untreated sample of Eucalyptus nitens were found to be 18.83 MJ/kg and 17.48 MJ/kg, and after thermal modification these increased up to 20.24 MJ/kg and 18.84 MJ/kg. Upon statistical analysis, the results for lignin showed a strong correlation with the temperature of thermal treatment and calorific value.
在德国哥廷根HAWK（Hochschule für Angewandte Wissenschaft und Kunst）测定了13个nitens桉树木材样品的总热值和净热值。在13个样品中，12个是热改性的，1个是未改性的。使用炸弹量热计测定样品的热值，Wentzel等人已经分析了木材成分（纤维素、半纤维素、木质素和提取物）。（2019）。在确定这些值后，R studio对样品进行统计分析，以找出热值、温度和木材成分之间的关系。发现未处理的nitens桉树样品的总热值和净热值分别为18.83MJ/kg和17.48MJ/kg，并且在热改性后，这些值增加到20.24MJ/kg和18.84MJ/kg。经过统计分析，木质素的结果与热处理温度和热值有很强的相关性。
{"title":"Analysing the effect of thermal modification on the calorific values of Eucalyptus nitens wood","authors":"Saurav Nepal, R. Wimmer, V. Zelinski","doi":"10.26614/les-wood.2021.v70n02a03","DOIUrl":"https://doi.org/10.26614/les-wood.2021.v70n02a03","url":null,"abstract":"Gross and net calorific value of 13 samples of Eucalyptus nitens wood were determined at HAWK (Hochschule für Angewandte Wissenschaft und Kunst), Göttingen, Germany. Among 13 samples, 12 were thermally modified and one was unmodified. Calorific values of samples were determined by using a bomb calorimeter, and the wood components (cellulose, hemicellulose, lignin, and extractives) already analysed by Wentzel et al. (2019). After determination of the values, samples were statistically analysed by R studio to find the relations among the calorific value, temperature, and wood components. The gross calorific value and net calorific value of the untreated sample of Eucalyptus nitens were found to be 18.83 MJ/kg and 17.48 MJ/kg, and after thermal modification these increased up to 20.24 MJ/kg and 18.84 MJ/kg. Upon statistical analysis, the results for lignin showed a strong correlation with the temperature of thermal treatment and calorific value.","PeriodicalId":52851,"journal":{"name":"Les","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49265106","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 : 2021-11-14DOI: 10.26614/les-wood.2021.v70n02a02
K. A. Afrifah, Enoch Adjei-Mensah
Alstonia boonei, an abundant lesser utilized species within the West African Subregion, was evaluated as an alternative raw material for pulp and paper production. The basic density (BD), fibre characteristics [fibre length (FL), fibre diameter (FD), lumen diameter (LD) and wall thickness (WT)], derived anatomical indices [Flexibility Ratio (FR), Slenderness Ratio (SR), Rigidity Coefficient (RC), Luce’s Shape Factor (LSF), Solids Factor (SF) and Runkel Ratio (RR)] and chemical composition (lignin, holocellulose, 1% NaOH solubility and ash contents) of A. boonei were studied to evaluate variation along the trunk (base, middle and top portions) and ascertain its suitability for pulp and paper production. Significant variations were observed in the density and fibre characteristics along the trunk of the tree. Although the FD was large, the observed adequate FL, thin-wall and large LD implied easy beating of fibres and manufacture of dense, smooth and strong papers. The favourable SF, RR, FR, RC, and LSF values obtained for the fibres would produce papers with suitable burst and tearing strengths and folding endurance. Chemically the lower lignin (< 30%), ash and 1% NaOH solubility and the high holocellulose contents of A. boonei, will generate a higher pulp yield. A. boonei although a low-density species, will be desirable for pulp and paper production.
{"title":"Anatomical and chemical characterization of Alstonia boonei for pulp and paper production","authors":"K. A. Afrifah, Enoch Adjei-Mensah","doi":"10.26614/les-wood.2021.v70n02a02","DOIUrl":"https://doi.org/10.26614/les-wood.2021.v70n02a02","url":null,"abstract":"Alstonia boonei, an abundant lesser utilized species within the West African Subregion, was evaluated as an alternative raw material for pulp and paper production. The basic density (BD), fibre characteristics [fibre length (FL), fibre diameter (FD), lumen diameter (LD) and wall thickness (WT)], derived anatomical indices [Flexibility Ratio (FR), Slenderness Ratio (SR), Rigidity Coefficient (RC), Luce’s Shape Factor (LSF), Solids Factor (SF) and Runkel Ratio (RR)] and chemical composition (lignin, holocellulose, 1% NaOH solubility and ash contents) of A. boonei were studied to evaluate variation along the trunk (base, middle and top portions) and ascertain its suitability for pulp and paper production. Significant variations were observed in the density and fibre characteristics along the trunk of the tree. Although the FD was large, the observed adequate FL, thin-wall and large LD implied easy beating of fibres and manufacture of dense, smooth and strong papers. The favourable SF, RR, FR, RC, and LSF values obtained for the fibres would produce papers with suitable burst and tearing strengths and folding endurance. Chemically the lower lignin (< 30%), ash and 1% NaOH solubility and the high holocellulose contents of A. boonei, will generate a higher pulp yield. A. boonei although a low-density species, will be desirable for pulp and paper production.","PeriodicalId":52851,"journal":{"name":"Les","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43387669","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 : 2021-09-27DOI: 10.26614/les-wood.2021.v70n02a01
Enej Lipovec Zupanc, G. Fajdiga, M. Humar
Wood is considered the leading building material throughout the history of mankind. Wood has several advantages over other construction materials, which also makes it one of the most promising materials of the future. The environmental aspect also plays a major role today, as wood is a natural, renewable resource whose processing is very energy-intensive. Due to its repeated and widespread use in construction, the prediction of mechanical properties and their change over time is also very well known, as the overall safety of all buildings also depends on it. Therefore, we compared the mechanical properties of fresh European larch (Larix decidua) and 400-year-old larch found in the Ruard manor house on the Stara Sava in Jesenice, where the renovation of Upper Sava Museum is currently underway. In order to predict what will happen to the wood in the long term, it is necessary to expose the wood to the same conditions, i.e. to change it with dynamic loads or material fatigue. The effect of aging on flexural strength has not been confirmed. Fatigue results show that old wood withstood about 18 times fewer load cycles than recent larch wood.
{"title":"Comparison of mechanical properties of recent and 400-year-old European larch","authors":"Enej Lipovec Zupanc, G. Fajdiga, M. Humar","doi":"10.26614/les-wood.2021.v70n02a01","DOIUrl":"https://doi.org/10.26614/les-wood.2021.v70n02a01","url":null,"abstract":"Wood is considered the leading building material throughout the history of mankind. Wood has several advantages over other construction materials, which also makes it one of the most promising materials of the future. The environmental aspect also plays a major role today, as wood is a natural, renewable resource whose processing is very energy-intensive. Due to its repeated and widespread use in construction, the prediction of mechanical properties and their change over time is also very well known, as the overall safety of all buildings also depends on it. Therefore, we compared the mechanical properties of fresh European larch (Larix decidua) and 400-year-old larch found in the Ruard manor house on the Stara Sava in Jesenice, where the renovation of Upper Sava Museum is currently underway. In order to predict what will happen to the wood in the long term, it is necessary to expose the wood to the same conditions, i.e. to change it with dynamic loads or material fatigue. The effect of aging on flexural strength has not been confirmed. Fatigue results show that old wood withstood about 18 times fewer load cycles than recent larch wood.","PeriodicalId":52851,"journal":{"name":"Les","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45478600","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 : 2021-06-28DOI: 10.26614/les-wood.2021.v70n01a05
Sergej Medved, E. Tudor, M. Barbu, T. Young
To achieve the zero-waste goal as well as sustainability, the use of the raw materials, especially those from nature, and wood in particular, has to be smart, meaning that the resource has to be used to its full potential. Since wood-based industry is associated with high intensity and the generation of a relatively large amount of residues, those residues should be used for the production of useful products, otherwise they will easily be classified as waste and afterwards used as a source of energy. To present a possible solution for wood residues like wood chips, wood particles and bark, we investigated the possibility of using wood and bark residues as constituents for the production of single layer insulation panel with a target thickness of 40 mm and target density of 0.2 g·cm-3. Thermal conductivity was determined using the steady state principle at three different temperature settings. The average thermal conductivities were determined between 49 mW·m-1·K-1 and 74 mW·m-1·K-1. The highest values were determined at boards made from bark, which also had the highest density (0,291 g·cm-3), while the lowest thermal conductivity was observed for boards made from spruce wood particles.
{"title":"Thermal conductivity of different bio-based insulation materials","authors":"Sergej Medved, E. Tudor, M. Barbu, T. Young","doi":"10.26614/les-wood.2021.v70n01a05","DOIUrl":"https://doi.org/10.26614/les-wood.2021.v70n01a05","url":null,"abstract":"To achieve the zero-waste goal as well as sustainability, the use of the raw materials, especially those from nature, and wood in particular, has to be smart, meaning that the resource has to be used to its full potential. Since wood-based industry is associated with high intensity and the generation of a relatively large amount of residues, those residues should be used for the production of useful products, otherwise they will easily be classified as waste and afterwards used as a source of energy. To present a possible solution for wood residues like wood chips, wood particles and bark, we investigated the possibility of using wood and bark residues as constituents for the production of single layer insulation panel with a target thickness of 40 mm and target density of 0.2 g·cm-3. Thermal conductivity was determined using the steady state principle at three different temperature settings. The average thermal conductivities were determined between 49 mW·m-1·K-1 and 74 mW·m-1·K-1. The highest values were determined at boards made from bark, which also had the highest density (0,291 g·cm-3), while the lowest thermal conductivity was observed for boards made from spruce wood particles.","PeriodicalId":52851,"journal":{"name":"Les","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45707632","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 : 2021-06-25DOI: 10.26614/les-wood.2021.v70n01a10
Marko M. Petrić, Milan Šernek
Prof. dr. Katarina Čufar je v marcu 2021 prejela Jesenkovo nagrado za življenjsko delo, ki je najprestižnejše priznanje Biotehniške fakultete Univerze v Ljubljani. To je tretja nagrada za Katarino Čufar v kratkem času, saj je konec leta 2020 prejela tudi Zlato plaketo Univerze v Ljubljani in Zoisovo priznanje Republike Slovenije za pomembne znanstvenoraziskovalne dosežke in uspešno pedagoško delo.
{"title":"Prof. dr. Katarina Čufar je prejela Jesenkovo nagrado za življenjsko delo","authors":"Marko M. Petrić, Milan Šernek","doi":"10.26614/les-wood.2021.v70n01a10","DOIUrl":"https://doi.org/10.26614/les-wood.2021.v70n01a10","url":null,"abstract":"Prof. dr. Katarina Čufar je v marcu 2021 prejela Jesenkovo nagrado za življenjsko delo, ki je najprestižnejše priznanje Biotehniške fakultete Univerze v Ljubljani. To je tretja nagrada za Katarino Čufar v kratkem času, saj je konec leta 2020 prejela tudi Zlato plaketo Univerze v Ljubljani in Zoisovo priznanje Republike Slovenije za pomembne znanstvenoraziskovalne dosežke in uspešno pedagoško delo.","PeriodicalId":52851,"journal":{"name":"Les","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47997738","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 : 2021-06-25DOI: 10.26614/les-wood.2021.v70n01a08
J. Resnik
{"title":"In memoriam: prof. dr. Jože Kovač (1930–2021)","authors":"J. Resnik","doi":"10.26614/les-wood.2021.v70n01a08","DOIUrl":"https://doi.org/10.26614/les-wood.2021.v70n01a08","url":null,"abstract":"","PeriodicalId":52851,"journal":{"name":"Les","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41703253","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 : 2021-06-25DOI: 10.26614/les-wood.2021.v70n01a07
Tina Drolc
{"title":"Oddelek za lesarstvo sodeluje kot partner v ciljnem raziskovalnem projektu za izboljšanje konkurenčnosti lesa listavcev","authors":"Tina Drolc","doi":"10.26614/les-wood.2021.v70n01a07","DOIUrl":"https://doi.org/10.26614/les-wood.2021.v70n01a07","url":null,"abstract":"","PeriodicalId":52851,"journal":{"name":"Les","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45200414","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 : 2021-06-21DOI: 10.26614/les-wood.2021.v70n01a06
Jožica Gričar, Katarina Čufar, Peter Prislan
Baze podatkov o nastajanju lesa in floema so pomembne za razumevanje vpliva podnebnih sprememb in izrednih vremenskih dogodkov na vrstno sestavo, vitalnost dreves, produkcijo ter kakovost lesa v slovenskih gozdovih. V tem članku predstavljamo najnovejše rezultate o debelinski rasti navadne smreke (Picea abies (L.) Karst.) z dveh rastišč v Sloveniji, na Panški reki (PAN – 400 m n. v.) in Menini planini (MEN – 1200 m n. v.) v letih 2009–2011. Poudarek je bil na sezonski dinamiki nastajanja ranega in kasnega lesa ter ranega in kasnega floema. Ugotovili smo, da rastiščne razmere v veliki meri vplivajo na sezonsko dinamiko nastajanja lesa in floema, kar se odraža v širini in strukturi prirastkov. Na višje ležečem rastišču MEN je bila rastna sezona približno mesec dni krajša (dolga slabe 4 mesece), posledično so bili letni prirastki ožji, in sicer v lesu za 39 % in v floemu za 15 %. Na MEN smo prehod iz ranega v kasni les v povprečju opazili le teden dni kasneje kot na PAN, medtem ko je prehod iz ranega v kasni floem nastopil v poprečju 20 dni kasneje. Informacije o vplivu rastiščnih razmer na debelinsko rast smreke in kakovost lesa so pomembne za vse deležnike v gozdno-lesni verigi, saj so lahko v pomoč pri sprejemanju ustreznih ukrepov upravljanja za prilagoditev spremenjenim razmeram.
{"title":"Nastajanje in struktura lesa in floema pri navadni smreki","authors":"Jožica Gričar, Katarina Čufar, Peter Prislan","doi":"10.26614/les-wood.2021.v70n01a06","DOIUrl":"https://doi.org/10.26614/les-wood.2021.v70n01a06","url":null,"abstract":"Baze podatkov o nastajanju lesa in floema so pomembne za razumevanje vpliva podnebnih sprememb in izrednih vremenskih dogodkov na vrstno sestavo, vitalnost dreves, produkcijo ter kakovost lesa v slovenskih gozdovih. V tem članku predstavljamo najnovejše rezultate o debelinski rasti navadne smreke (Picea abies (L.) Karst.) z dveh rastišč v Sloveniji, na Panški reki (PAN – 400 m n. v.) in Menini planini (MEN – 1200 m n. v.) v letih 2009–2011. Poudarek je bil na sezonski dinamiki nastajanja ranega in kasnega lesa ter ranega in kasnega floema. Ugotovili smo, da rastiščne razmere v veliki meri vplivajo na sezonsko dinamiko nastajanja lesa in floema, kar se odraža v širini in strukturi prirastkov. Na višje ležečem rastišču MEN je bila rastna sezona približno mesec dni krajša (dolga slabe 4 mesece), posledično so bili letni prirastki ožji, in sicer v lesu za 39 % in v floemu za 15 %. Na MEN smo prehod iz ranega v kasni les v povprečju opazili le teden dni kasneje kot na PAN, medtem ko je prehod iz ranega v kasni floem nastopil v poprečju 20 dni kasneje. Informacije o vplivu rastiščnih razmer na debelinsko rast smreke in kakovost lesa so pomembne za vse deležnike v gozdno-lesni verigi, saj so lahko v pomoč pri sprejemanju ustreznih ukrepov upravljanja za prilagoditev spremenjenim razmeram.","PeriodicalId":52851,"journal":{"name":"Les","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49587639","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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