The volume of greenhouse gases （GHGs） emitted during the process from product manufacturing step to the construction process in the life cycle of a wooden school building （two stories; total floor area : 407.2 m 2 ） constructed using cross-laminated timber （CLT） was quantified. GHG emissions were also quantified for school buildings with a reinforced concrete structure （hereafter, “RC structure”） and for those with a steel structure （hereafter, “S structure”）, keeping all other specifications constant. The GHG emissions were then compared between scenarios. The results were as follows. The volume of GHG emissions from the CLT products used to construct the wooden school building using the CLT method, over the life cycle of the building, was 442 kg CO 2 e/m 3 . The volume of GHG emissions for the wooden school building itself was 168 t CO 2 e. And, the volume of GHG emissions for the school buildings with the RC and S structures was 242 t CO 2 e and 206 t CO 2 e, respectively. These results showed that using the CLT construction method to build structures for a school can reduce GHG emissions by approximately 30.6% and 18.5%, respectively, compared to using an RC structure or an S structure. (cid:9487)(cid:9513)(cid:9533)(cid:9531)(cid:9523)(cid:9526)(cid:9512)(cid:9527) : LCCO 2 , GHG emission, wooden school building, CLT method.
木质学校建筑(两层;总建筑面积:407.2平方米)，使用交叉层压木材(CLT)进行了量化。在保持所有其他规格不变的情况下，还量化了钢筋混凝土结构(以下简称“RC结构”)和钢结构(以下简称“S结构”)校舍的温室气体排放。然后比较不同情景下的温室气体排放量。结果如下:使用CLT方法建造木制学校建筑的CLT产品的温室气体排放量，在建筑的生命周期内，为442千克二氧化碳/立方米。木质校舍本身的温室气体排放量为168 t co2 e, RC和S结构校舍的温室气体排放量分别为242 t co2 e和206 t co2 e。这些结果表明，与使用RC结构或S结构相比，使用CLT建造方法为学校建造结构可以分别减少约30.6%和18.5%的温室气体排放。(cid:9487)(cid:9513)(cid:9533)(cid:9531)(cid:9523)(cid:9526)(cid:9512)(cid:9527): LCCO 2，温室气体排放，木制学校建筑，CLT方法。
{"title":"Quantifying the Greenhouse Gas Emissions in the Construction of Wooden School Structures Using the Cross-laminated Timber Construction Method","authors":"Yuki Fuchigami, Kenta Watanabe, T. Nakai","doi":"10.2488/jwrs.66.101","DOIUrl":"https://doi.org/10.2488/jwrs.66.101","url":null,"abstract":"The volume of greenhouse gases （GHGs） emitted during the process from product manufacturing step to the construction process in the life cycle of a wooden school building （two stories; total floor area : 407.2 m 2 ） constructed using cross-laminated timber （CLT） was quantified. GHG emissions were also quantified for school buildings with a reinforced concrete structure （hereafter, “RC structure”） and for those with a steel structure （hereafter, “S structure”）, keeping all other specifications constant. The GHG emissions were then compared between scenarios. The results were as follows. The volume of GHG emissions from the CLT products used to construct the wooden school building using the CLT method, over the life cycle of the building, was 442 kg CO 2 e/m 3 . The volume of GHG emissions for the wooden school building itself was 168 t CO 2 e. And, the volume of GHG emissions for the school buildings with the RC and S structures was 242 t CO 2 e and 206 t CO 2 e, respectively. These results showed that using the CLT construction method to build structures for a school can reduce GHG emissions by approximately 30.6% and 18.5%, respectively, compared to using an RC structure or an S structure. (cid:9487)(cid:9513)(cid:9533)(cid:9531)(cid:9523)(cid:9526)(cid:9512)(cid:9527) : LCCO 2 , GHG emission, wooden school building, CLT method.","PeriodicalId":49800,"journal":{"name":"Mokuzai Gakkaishi","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2020-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43345522","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this research, laboratory sheets made from rice straw bleached chemical pulps were impregnated with a ZnCl2 aqueous solution to prepare high wet-strength paper, and the effects of the concentration of the ZnCl2 solution, impregnation temperature and period, and ethanol washing period were evaluated through single factor tests, The optimal conditions was determined to be 60%, 65 oC, 10 min, and 12 min, respectively. Under these conditions, the dry tensile and dry burst indices of the sheet prepared from the impregnated laboratory sheets doubled, and both the wet indices quadrupled as compared to those from untreated laboratory sheets. There were no significant changes in the cellulose crystal form and crystallinity. However, the paper surface morphology changed significantly.
{"title":"Preparation of High Wet-Strength Paper from Rice Straw Pulp by Treatment with ZnCl2 Aqueous Solution","authors":"Xu Yinchao, Guangfan Jin, Rui Zhai, Chunfeng Zhu, Lijun Wang, Anbo Wu, A. Nakagawa-izumi","doi":"10.2488/jwrs.66.46","DOIUrl":"https://doi.org/10.2488/jwrs.66.46","url":null,"abstract":"In this research, laboratory sheets made from rice straw bleached chemical pulps were impregnated with a ZnCl2 aqueous solution to prepare high wet-strength paper, and the effects of the concentration of the ZnCl2 solution, impregnation temperature and period, and ethanol washing period were evaluated through single factor tests, The optimal conditions was determined to be 60%, 65 oC, 10 min, and 12 min, respectively. Under these conditions, the dry tensile and dry burst indices of the sheet prepared from the impregnated laboratory sheets doubled, and both the wet indices quadrupled as compared to those from untreated laboratory sheets. There were no significant changes in the cellulose crystal form and crystallinity. However, the paper surface morphology changed significantly.","PeriodicalId":49800,"journal":{"name":"Mokuzai Gakkaishi","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2020-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43751381","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
To measure the modulus of rupture （MOR） of particleboard, a method for determining sample size was developed. First, the MOR of a large number of samples was measured. A total of 10000 sample means were calculated by applying Monte Carlo simulations to the measured MORs, and relationships between sample size and sample mean were analyzed. When the sample size was 15, 9605 sample means among the 10000 sample means were within in the 95% confidence interval. As a result, the sample size was set at 15, and the probability of means occurring within the interval was very high, i.e., 96.05%. Next, the 5, 10, 20, and 30% points of the 9605 sample means were calculated, which reached the 95% confidence interval when the sample sizes were 10, 8, 4, and 2, respectively. For example, when the sample size was 2, the probability of means occurring within the interval was relatively high, i.e., 67.55%. Because the general method calculated a sample size of 28, our method could markedly decrease the sample size. (cid:9487)(cid:9513)(cid:9533)(cid:9531)(cid:9523)(cid:9526)(cid:9512)(cid:9527) : particleboard, modulus of rupture, sample size, Monte Carlo simulation, 95% confidence interval.
{"title":"Method for Determining Sample Size to Measure MOR of Particleboard Using Monte Carlo Simulation","authors":"H. Korai, Ken Watanabe","doi":"10.2488/jwrs.66.1","DOIUrl":"https://doi.org/10.2488/jwrs.66.1","url":null,"abstract":"To measure the modulus of rupture （MOR） of particleboard, a method for determining sample size was developed. First, the MOR of a large number of samples was measured. A total of 10000 sample means were calculated by applying Monte Carlo simulations to the measured MORs, and relationships between sample size and sample mean were analyzed. When the sample size was 15, 9605 sample means among the 10000 sample means were within in the 95% confidence interval. As a result, the sample size was set at 15, and the probability of means occurring within the interval was very high, i.e., 96.05%. Next, the 5, 10, 20, and 30% points of the 9605 sample means were calculated, which reached the 95% confidence interval when the sample sizes were 10, 8, 4, and 2, respectively. For example, when the sample size was 2, the probability of means occurring within the interval was relatively high, i.e., 67.55%. Because the general method calculated a sample size of 28, our method could markedly decrease the sample size. (cid:9487)(cid:9513)(cid:9533)(cid:9531)(cid:9523)(cid:9526)(cid:9512)(cid:9527) : particleboard, modulus of rupture, sample size, Monte Carlo simulation, 95% confidence interval.","PeriodicalId":49800,"journal":{"name":"Mokuzai Gakkaishi","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2020-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69067628","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Guangfan Jin, Vu Thang Do, Yunmeng Wu, Kuan-hsuan Lin, Chunfeng Zhu, A. Nakagawa-izumi
{"title":"Chemical Characteristics of Bamboo (Phyllostachys pubescens) Fiber Fractions Produced by a Laboratory Thermomechanical Refiner","authors":"Guangfan Jin, Vu Thang Do, Yunmeng Wu, Kuan-hsuan Lin, Chunfeng Zhu, A. Nakagawa-izumi","doi":"10.2488/jwrs.66.16","DOIUrl":"https://doi.org/10.2488/jwrs.66.16","url":null,"abstract":"","PeriodicalId":49800,"journal":{"name":"Mokuzai Gakkaishi","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2020-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69067638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Marina Totsuka, K. Aoki, Masahiro Inayama, Kimihiko Morita
Partial compressive properties of lateral faces in Cross Laminated Timber （CLT） are important when we calculate the criteria for connections. However, the technical knowledge from studies of compression behavior of lateral faces in CLT is still limited. In this study, we determined partial compressive properties, yield stress, and initial and secondary stiffness for lateral faces when using CLT made of Japanese cedar. There were 24 types of specimens that varied in width of loading plates, location of loading plates, presence or absence of edge bonds or side margins. Results of experiments showed that the width of the applied loading device and of the side margin have a potent influence. It is assumed that the effect of the width of the applied loading device is a size effect. The size margin effect was greater when the width of the loading plates decreased. Specimens with greater than 100 mm side margins can be considered to be of infinite length. The presence of edge bonds contributes to increasing partial compressive strength. On the other hand, the perimeters of the location of the loading plates do not have a potent influence.
{"title":"Partial Compressive Properties of Cross Laminated Timber I.","authors":"Marina Totsuka, K. Aoki, Masahiro Inayama, Kimihiko Morita","doi":"10.2488/jwrs.66.8","DOIUrl":"https://doi.org/10.2488/jwrs.66.8","url":null,"abstract":"Partial compressive properties of lateral faces in Cross Laminated Timber （CLT） are important when we calculate the criteria for connections. However, the technical knowledge from studies of compression behavior of lateral faces in CLT is still limited. In this study, we determined partial compressive properties, yield stress, and initial and secondary stiffness for lateral faces when using CLT made of Japanese cedar. There were 24 types of specimens that varied in width of loading plates, location of loading plates, presence or absence of edge bonds or side margins. Results of experiments showed that the width of the applied loading device and of the side margin have a potent influence. It is assumed that the effect of the width of the applied loading device is a size effect. The size margin effect was greater when the width of the loading plates decreased. Specimens with greater than 100 mm side margins can be considered to be of infinite length. The presence of edge bonds contributes to increasing partial compressive strength. On the other hand, the perimeters of the location of the loading plates do not have a potent influence.","PeriodicalId":49800,"journal":{"name":"Mokuzai Gakkaishi","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2020-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48248907","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study aimed to evaluate the economic impacts of increasing the ratio of domestic timber used in wooden framework for residential construction. We performed two assessments: a simulation in which the ratio of domestic timber utilization in Japanese wooden framework residential industry is increased by 1% above the actual ratio, and a case analysis of the leading housing company, T Home. The findings showed that increasing the ratio of domestic timber not only had an overall economic effect but also affected the earnings of the housing manufacturer in some cases. On the other hand, in the simulation, induced production increased by 4.49 billion yen and the gross value added increased by 2.10 billion yen if the ratio of domestic timber utilization in the Japanese wooden-framework residential construction industry increased by 1% above the actual ratio of 2018. The results of the simulation and the case analysis proved that the economic impact on the forest products industry is larger when wood products are processed in Japan, even if they originate from a foreign country and the economic impact on forestry is larger when lumber rather than either plywood or laminated timber is used.
{"title":"Economic Impacts of Increases in Domestic Timber Utilization in Wooden Framework for Residential Construction","authors":"Soei Kawamura, M. Inoue","doi":"10.2488/jwrs.66.23","DOIUrl":"https://doi.org/10.2488/jwrs.66.23","url":null,"abstract":"This study aimed to evaluate the economic impacts of increasing the ratio of domestic timber used in wooden framework for residential construction. We performed two assessments: a simulation in which the ratio of domestic timber utilization in Japanese wooden framework residential industry is increased by 1% above the actual ratio, and a case analysis of the leading housing company, T Home. The findings showed that increasing the ratio of domestic timber not only had an overall economic effect but also affected the earnings of the housing manufacturer in some cases. On the other hand, in the simulation, induced production increased by 4.49 billion yen and the gross value added increased by 2.10 billion yen if the ratio of domestic timber utilization in the Japanese wooden-framework residential construction industry increased by 1% above the actual ratio of 2018. The results of the simulation and the case analysis proved that the economic impact on the forest products industry is larger when wood products are processed in Japan, even if they originate from a foreign country and the economic impact on forestry is larger when lumber rather than either plywood or laminated timber is used.","PeriodicalId":49800,"journal":{"name":"Mokuzai Gakkaishi","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2020-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44069720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Natsuki Tomita, K. Murata, Masashi Nakamura, H. Akitsu, H. Ohsaki
is a pioneer species that has not been used sufficiently in practical applications even though it is the most abundant wood source in the Hokkaido prefecture. We believe that it has potential as a valuable material for use in baseball bats. Assuming that the critical factor for baseball bats is an impact strength, we elucidated the relationships between slope of grain （(cid:9495)(cid:9523)(cid:9483)） and impact strength or impact fracture energy of dakekanba wood by conducting impact bending tests. Results revealed that the Hankinson equation could be used to calculate these relationships to impact strength because they were similar to those considered in previous studies of impact fracture energy. Cylindrical wood specimens such as bat grips were assessed in the impact bending tests, and dakekanba wood was compared with woods used for commercial bats. After impact strength were corrected based on (cid:9495)(cid:9523)(cid:9483) and density, both strength and fracture energy of dakekanba wood were found to be nearly the same as those of commercial wood species for baseball bats. Prototype bats of dakekanba wood were manufactured and experimentally used by a baseball club at Kyoto University. The prototypes were confirmed to have sufficient durability, as no bats broke during their one-week trial use. On a questionnaire survey, players responded with “good” or “normal” regarding bat feeling, flown distance, etc. after hitting with the prototypes. Our study reveals that dakekanba wood has good potential as a baseball-bat material.
{"title":"Use of Dakekanba Wood for Baseball-bats","authors":"Natsuki Tomita, K. Murata, Masashi Nakamura, H. Akitsu, H. Ohsaki","doi":"10.2488/jwrs.66.39","DOIUrl":"https://doi.org/10.2488/jwrs.66.39","url":null,"abstract":"is a pioneer species that has not been used sufficiently in practical applications even though it is the most abundant wood source in the Hokkaido prefecture. We believe that it has potential as a valuable material for use in baseball bats. Assuming that the critical factor for baseball bats is an impact strength, we elucidated the relationships between slope of grain （(cid:9495)(cid:9523)(cid:9483)） and impact strength or impact fracture energy of dakekanba wood by conducting impact bending tests. Results revealed that the Hankinson equation could be used to calculate these relationships to impact strength because they were similar to those considered in previous studies of impact fracture energy. Cylindrical wood specimens such as bat grips were assessed in the impact bending tests, and dakekanba wood was compared with woods used for commercial bats. After impact strength were corrected based on (cid:9495)(cid:9523)(cid:9483) and density, both strength and fracture energy of dakekanba wood were found to be nearly the same as those of commercial wood species for baseball bats. Prototype bats of dakekanba wood were manufactured and experimentally used by a baseball club at Kyoto University. The prototypes were confirmed to have sufficient durability, as no bats broke during their one-week trial use. On a questionnaire survey, players responded with “good” or “normal” regarding bat feeling, flown distance, etc. after hitting with the prototypes. Our study reveals that dakekanba wood has good potential as a baseball-bat material.","PeriodicalId":49800,"journal":{"name":"Mokuzai Gakkaishi","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2020-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47216642","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The NaOH-urea pretreatment system under mild temperatures was used to modify mechanical pulp properties of wheat straw, and the effects of alkali impregnation time and treatment temperature time were evaluated through single factor tests. The results showed that the optimal conditions were chosen as NaOH and urea concentrations of 5% and 3.5%, impregnation time of 10 min, treatment temperature of 50 ºC and treatment time of 60 min. Compared with the results of the NaOH-pretreated chemi-mechanical pulp production, the refining energy consumption of the mechanical pulp prepared by the NaOH-urea system was decreased by 14%, while screened yield and brightness of the pulp were increased by 1.5% and 4.2% （point） and sheet density, tensile index and burst index were increased by 3.5%, 20% and 17%, respectively.
{"title":"Strength Improvement of Wheat Straw Chemi-mechanical Pulp by the NaOH-urea Pretreatment","authors":"Guangfan Jin, Rui Zhai, Chunfeng Zhu, Xu Yinchao, Lijun Wang, Jianye Wang, A. Nakagawa-izumi","doi":"10.2488/jwrs.65.243","DOIUrl":"https://doi.org/10.2488/jwrs.65.243","url":null,"abstract":"The NaOH-urea pretreatment system under mild temperatures was used to modify mechanical pulp properties of wheat straw, and the effects of alkali impregnation time and treatment temperature time were evaluated through single factor tests. The results showed that the optimal conditions were chosen as NaOH and urea concentrations of 5% and 3.5%, impregnation time of 10 min, treatment temperature of 50 ºC and treatment time of 60 min. Compared with the results of the NaOH-pretreated chemi-mechanical pulp production, the refining energy consumption of the mechanical pulp prepared by the NaOH-urea system was decreased by 14%, while screened yield and brightness of the pulp were increased by 1.5% and 4.2% （point） and sheet density, tensile index and burst index were increased by 3.5%, 20% and 17%, respectively.","PeriodicalId":49800,"journal":{"name":"Mokuzai Gakkaishi","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2019-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43454567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The wood qualities of birch species grown in a plantation in Atsuma, Hokkaido, were investigated. Shirakamba (Japanese white birch ; Betula platyphylla), Udaikamba (Japanese red birch ; Betula maximowicziana) and Dakekamba(Erman’s birch ; Betula ermanii) were used. Disks were cut from the trunk at part of 2 m height above the ground and the ring widths were measured. Bending tests and compression tests were carried out. The initial radial growth of Dakekamba was smaller than that of the other species. Wood density decreased from bark to pith. The closer to the pith, the lower the bending and compression strengths were. There was little change in density or the bending and compression strengths at ground height. The plantation grown birches showed similar strength performance as naturally grown birches.
{"title":"The Timber Properties of Birch Grown in a Plantation in Atsuma, Hokkaido","authors":"H. Ohsaki, S. Murakami, H. Akitsu","doi":"10.2488/jwrs.65.189","DOIUrl":"https://doi.org/10.2488/jwrs.65.189","url":null,"abstract":"The wood qualities of birch species grown in a plantation in Atsuma, Hokkaido, were investigated. Shirakamba (Japanese white birch ; Betula platyphylla), Udaikamba (Japanese red birch ; Betula maximowicziana) and Dakekamba(Erman’s birch ; Betula ermanii) were used. Disks were cut from the trunk at part of 2 m height above the ground and the ring widths were measured. Bending tests and compression tests were carried out. The initial radial growth of Dakekamba was smaller than that of the other species. Wood density decreased from bark to pith. The closer to the pith, the lower the bending and compression strengths were. There was little change in density or the bending and compression strengths at ground height. The plantation grown birches showed similar strength performance as naturally grown birches.","PeriodicalId":49800,"journal":{"name":"Mokuzai Gakkaishi","volume":null,"pages":null},"PeriodicalIF":0.3,"publicationDate":"2019-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46150948","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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