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我国林业科技研究热点迁移——以《林业科学》2000—2024年刊载论文为例
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作者 王艳娜 石红青 +1 位作者 张博文 王媛 《国家林业和草原局管理干部学院学报》 2025年第2期60-68,共9页
以《林业科学》2000—2024年发文为研究对象,利用文献计量指标和CiteSpace知识图谱分析软件,对期刊文章的研究热点和期刊影响力进行分析。结果表明,2000—2024年《林业科学》刊文主要的发文机构是东北林业大学、北京林业大学以及中国林... 以《林业科学》2000—2024年发文为研究对象,利用文献计量指标和CiteSpace知识图谱分析软件,对期刊文章的研究热点和期刊影响力进行分析。结果表明,2000—2024年《林业科学》刊文主要的发文机构是东北林业大学、北京林业大学以及中国林业科学研究院等高校和科研院所,杉木、马尾松、杨树等是《林业科学》刊文的主要关键词。文献计量分析结果表明,《林业科学》发文热点从早期的“单一树种培育”向“生态系统多功能管理”的机理性、系统性、应用性综合研究迁移。分析《林业科学》2000—2024年期刊文章研究热点与变迁,从而探究我国林业科技研究的热点变化趋势,为打造更高水平林业科技期刊提供参考。 展开更多
关键词 《林业科学》 林业科技期刊 学术影响力 影响力分析 林业高质量发展
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Eco-Friendly Particleboards Produced with Banana Tree(Musa paradisiaca)Pseudostem Fibers Bonded with Cassava Starch and Urea-Formaldehyde Adhesives
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作者 Prosper Mensah Rafael Rodolfode Melo +3 位作者 Edgley Alves de Oliveira Paula Alexandre Santos Pimenta Julianade Moura Fernando Rusch 《Journal of Renewable Materials》 2025年第7期1475-1489,共15页
The increase in wood and wood-based products in the construction and furniture sectors has grown exponentially,generating severe environmental and socioeconomic impacts.Particleboard panels have been the main cost-ben... The increase in wood and wood-based products in the construction and furniture sectors has grown exponentially,generating severe environmental and socioeconomic impacts.Particleboard panels have been the main cost-benefit option on the market due to their lightness and lower cost compared to solid wood.However,the synthetic adhesives used in producing traditional particleboard panels cause serious harm to human health.Developing particleboard panels with fibrous waste and natural adhesives could be a sustainable alternative for these sectors.The work aimed to create particleboards with fibrous wastes from the pseudostem of the banana tree(Musa paradisiaca)and different proportions of the natural adhesive cassava starch-CS in replacement of synthetic adhesive urea-formaldehyde-UF.Five experimental groups were manufactured with banana trees and different percentages of UF and CS adhesives,namely(100UF–0%CS),(50%UF–50%CS),(30%UF–70%CS),(10%UF–90%CS)and(0%UF–100%CS).The particleboards had their physical-mechanical properties determined.The apparent density values did not show significant variation between the assessed treatments.Regarding the water absorption and thickness swelling,the best performances were observed for the panels made without the addition of CS(100%UF).For the mechanical properties of static bending strength and Janka hardness,it was identified that adding up to 50%CS did not interfere with the quality of the panels.These analyses show that the particleboard panels produced with wastes of the banana tree bonded with natural CS adhesivemay be an economically viable and environmentally correct alternative,positively strengthening the development of sustainable strategies. 展开更多
关键词 Plant fibers vegetable waste harnessing bioadhesives physical and technological properties sustainable development
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Unraveling key factors that influence and shape fluid flow dynamics in Brazilian salt Lagoon stromatolites: A case study in pre-salt analogues
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作者 Herson Oliveira da Rocha Roseane Marchezi Missagia +5 位作者 Marco Antonio Rodrigues de Ceia Andre Oliveira Martins Rafaella Rocha Baggieri Irineu de Azevedo Lima Neto Victor Hugo Santos Lucas Cesar Oliveira 《Petroleum Science》 2025年第3期1080-1097,共18页
This study analyzes Brazilian stromatolites in Lagoa Salgada,serving as analogs for pre-salt rocks in the Santos and Campos basins.Despite their excellent petrophysical properties,such as high porosity and permeabilit... This study analyzes Brazilian stromatolites in Lagoa Salgada,serving as analogs for pre-salt rocks in the Santos and Campos basins.Despite their excellent petrophysical properties,such as high porosity and permeability,these reservoirs present challenges in fluid flow modeling and simulation.The research investigates various factors influencing the development of carbonate reservoirs,including diagenetic processes employing several techniques,such as microcomputed tomography(micro-CT)and digital rock physics(DRP),to study petrophysical and geological characteristics.Additionally,through numerical simulations,the properties of fluid flow in different microfacies of stromatolites are estimated,with particular emphasis on understanding and highlighting changes in the direction of fluid flow in the three characterized microfacies.These findings offer crucial insights into optimizing oil and gas exploration and production techniques in carbonate reservoirs,providing a comprehensive understanding of the dynamics of fluid transport in porous media,especially in terms of directional changes within stromatolites. 展开更多
关键词 Fluid dynamics in stromatolites Carbonate reservoirs Numerical simulation Pre-salt analogs
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Comparing carbon sequestration efficiency in chemically separated soil organic carbon fractions under long-term fertilization in three major Chinese croplands
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作者 Hu Xu Adnan Mustafa +5 位作者 Lu Zhang Shaomin Huang Hongjun Gao Mohammad Tahsin Karimi Nezhad Nan Sun Minggang Xu 《Journal of Integrative Agriculture》 2025年第7期2841-2856,共16页
The combined application of organic manure and chemical fertilizers is an effective way to enhance soil organic carbon(SOC)sequestration through its influences on organic carbon(OC)input and the stability of SOC fract... The combined application of organic manure and chemical fertilizers is an effective way to enhance soil organic carbon(SOC)sequestration through its influences on organic carbon(OC)input and the stability of SOC fractions.However,there is limited information on the carbon sequestration efficiency(CSE)of chemically separated SOC fractions and its response to OC input under long-term fertilization regimes,especially at different sites.This study used three long-term fertilization experiments in Gongzhuling,Zhengzhou and Qiyang spanning 20 years to compare the stocks and CSE in four different OC fractions(very labile OC,labile OC,less labile OC,and non-labile OC)and their relationships with annual OC input.Three treatments of no fertilization(CK),chemical nitrogen,phosphorous,and potassium fertilizers(NPK),and chemical NPK combined with manure(NPKM)were employed.The results showed that compared with CK,NPKM resulted in enhanced SOC stocks and sequestration rates as well as CSE levels of all fractions irrespective of experimental site.Specifically for the very labile and non-labile OC fractions,NPKM significantly increased the SOC stocks by 43 and 83%,77 and 86%,and 73 and 82%in Gongzhuling,Qiyang,and Zhengzhou relative to CK,respectively.However,the greatest changes in SOC stock relative to the initial value were associated with non-labile OC fractions in Gongzhuling,Zhengzhou,and Qiyang,which reached 6.65,7.16,and 7.35 Mg ha^(-1) under NPKM.Similarly,the highest CSE was noted for non-labile OC fractions under NPKM followed sequentially by the very labile OC,labile OC,and less-labile OC fractions,however a CSE of 8.56%in the non-labile OC fraction for Gongzhuling was higher than the values of 6.10 and 4.61%in Zhengzhou and Qiyang,respectively.In addition,the CSE for the passive pool(very labile+labile OC fractions)was higher than the active pool(less-labile+non-labile OC fractions),with the highest value in Gongzhuling.The redundancy analysis revealed that the CSEs of fractions and pools were negatively influenced by annual OC input,mean annual precipitation and temperature,but positively influenced by the initial SOC and total nitrogen contents.This suggests that differential stability of sequestered OC is further governed by indigenous site characteristics and variable amounts of annual OC input. 展开更多
关键词 long-term field experiment fertilization carbon sequestration efficiency organic carbon stability organic carbon fractionation
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Management of sessile oak(Quercus petraea(Matt.)Liebl.),a major forest species in Europe
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作者 Valeriu‑Norocel Nicolescu Torsten Vor +19 位作者 Robert Brus Martina Đodan Sanja Perić Vilém Podrázský Siniša Andrašev Evgeni Tsavkov Sezgin Ayan Cengiz Yücedağ Pande Trajkov Dana Dina Kolevska Cornelia Buzatu‑Goanță Michal Pástor Vladimír Mačejovský Juraj Modranský Marcin Klisz Wojciech Gil Vasyl Lavnyy Palle Madsen Nicola La Porta Debbie Bartlett 《Journal of Forestry Research》 2025年第5期23-59,共37页
Sessile oak(Quercus petraea(Matt.)Liebl.)is widely distributed across most of Europe particularly the hills and lower mountain ranges,so is considered“the oak of the mountains”.This species grows on a wide variety o... Sessile oak(Quercus petraea(Matt.)Liebl.)is widely distributed across most of Europe particularly the hills and lower mountain ranges,so is considered“the oak of the mountains”.This species grows on a wide variety of soils and at altitudes ranging from sea level to 2200 m,especially in Atlantic and sub-Mediterranean climates,and it is sensitive to low winter temperatures,early and late frosts,as well as high summer temperatures.Sessile oak forms both pure and mixed stands especially with broadleaves such as European beech,European hornbeam,small-leaved lime and Acer spp.These form the understorey of sessile oak stands,promoting the natural shedding of lower branches of the oak and protecting the trunk against epicormic branches.Sessile oak is a long-lived,light-demanding and wind-firm species,owing to its taproot and heart-shaped root system.Its timber,one of the most valuable in Europe,is important for fur-niture-making(both solid wood and veneer),construction,barrels,railway sleepers,and is also used as fuelwood.It is one of the few major tree species in Europe that is regener-ated by seed(naturally or artificially)and by stump shoots in high forest,coppice-with-standards and coppice forests.Sessile oak forests are treated in both regular and irregular systems involving silvicultural techniques such as uniform shelterwood,group shelterwood,irregular shelterwood,irregular high forest,coppice-with-standards and simple coppice.Young naturally regenerated stands are managed by weeding,release cutting and cleaning-respacing,keeping the stands quite dense for good natural pruning.Plantations are based on(1)2-4-year old bare-root or container-grown seedlings produced in nurseries using seeds from genetic resources,seed stands and seed orchards.The density of sessile oak plantations(mostly in rows,but also in clusters)is usually between 4000 and 6000 ind.ha^(−1).Sessile oak silviculture of mature stands includes crown thinning,focus-ing on final crop trees(usually a maximum of 100 ind.ha^(−1))and targeting the production of large-diameter and high quality trees at long rotation ages(mostly over 120 years,sometimes 250-300 years).In different parts of Europe,conversion of simple coppices and coppice-with-standards to high forests is continuing.Even though manage-ment of sessile oak forests is very intensive and expensive,requiring active human intervention,the importance of this species in future European forests will increase in the con-text of climate change due to its high resistance to distur-bance,superior drought tolerance and heat stress resistance. 展开更多
关键词 Sessile oak Ecological requirements Timber VULNERABILITIES MANAGEMENT
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我国林草科技期刊现状与高质量发展路径 被引量:1
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作者 朱安明 刘道平 +3 位作者 周固国 唐玮璐 沈娜娉 石红青 《国家林业和草原局管理干部学院学报》 2024年第1期44-51,共8页
本研究基于量化数据对林草科技期刊本底情况、中英文林草科技期刊学术传播能力进行全面分析,旨在客观反映并总结其在建设发展中存在的核心问题,提出林草科技期刊影响力提升策略。研究发现,林草科技期刊存在整体水平和质量有待提高、体... 本研究基于量化数据对林草科技期刊本底情况、中英文林草科技期刊学术传播能力进行全面分析,旨在客观反映并总结其在建设发展中存在的核心问题,提出林草科技期刊影响力提升策略。研究发现,林草科技期刊存在整体水平和质量有待提高、体制和运行机制亟待改革、办刊条件亟待改善等问题。建议通过强化编辑队伍建设、提高国际化办刊水平、推进数字出版和集群化建设、提升参与智库决策服务能力、提升服务学科能力和探索知识内容科普化传播路径等方式,实现林草科技期刊高质量发展。 展开更多
关键词 林草科技期刊 高质量发展 现状 路径
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Plant growth and metabolism of exotic and native Crotalaria species for mine land rehabilitation in the Amazon 被引量:1
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作者 Hemelyn Soares das Chagas Rafael Silva Guedes +6 位作者 Markus Gastauer Paula Godinho Ribeiro Allan Klynger da Silva Lobato Cecílio Frois Caldeira Fabrício William deÁvila AndréRodrigues dos Reis Silvio Junio Ramos 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期143-154,共12页
Despite its enormous benefits,mining is respon-sible for intense changes to vegetation and soil properties.Thus,after extraction,it is necessary to rehabilitate the mined areas,creating better conditions for the estab... Despite its enormous benefits,mining is respon-sible for intense changes to vegetation and soil properties.Thus,after extraction,it is necessary to rehabilitate the mined areas,creating better conditions for the establishment of plant species which is challenging.This study evaluated mineral and organic fertilization on the growth,and carbon and nitrogen(N)metabolism of two Crotalaria species[Cro-talaria spectabilis(exotic species)and Crotalaria maypu-rensis(native species from Carajás Mineral Province(CMP)]established on a waste pile from an iron mine in CMP.A control(without fertilizer application)and six fertilization mixtures were tested(i=NPK;ii=NPK+micronutrients;iii=NPK+micronutrients+organic compost;iv=PK;v=PK+micronutrients;vi=PK+micronutrients+organic compost).Fertilization contributed to increased growth of both species,and treatments with NPK and micronutrients had the best results(up to 257%cf.controls),while organic fertilization did not show differences.Exotic Crotalaria had a greater number of nodules,higher nodule dry mass,chlorophyll a and b contents and showed free ammonium as the predominant N form,reflecting greater increments in biomass compared to native species.Although having lower growth,the use of this native species in the rehabilitation of mining areas should be considered,mainly because it has good development and meets current government legislation as an opportunity to restore local biodiversity. 展开更多
关键词 Biological nitrogen fixation Mining Nitrogen metabolism Plant nutrition
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Forecasting and trading cryptocurrencies with machine learning under changing market conditions 被引量:23
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作者 Helder Sebastiao Pedro Godinho 《Financial Innovation》 2021年第1期61-90,共30页
This study examines the predictability of three major cryptocurrencies—bitcoin,ethereum,and litecoin—and the profitability of trading strategies devised upon machine learning techniques(e.g.,linear models,random for... This study examines the predictability of three major cryptocurrencies—bitcoin,ethereum,and litecoin—and the profitability of trading strategies devised upon machine learning techniques(e.g.,linear models,random forests,and support vector machines).The models are validated in a period characterized by unprecedented turmoil and tested in a period of bear markets,allowing the assessment of whether the predictions are good even when the market direction changes between the validation and test periods.The classification and regression methods use attributes from trading and network activity for the period from August 15,2015 to March 03,2019,with the test sample beginning on April 13,2018.For the test period,five out of 18 individual models have success rates of less than 50%.The trading strategies are built on model assembling.The ensemble assuming that five models produce identical signals(Ensemble 5)achieves the best performance for ethereum and litecoin,with annualized Sharpe ratios of 80.17%and 91.35%and annualized returns(after proportional round-trip trading costs of 0.5%)of 9.62%and 5.73%,respectively.These positive results support the claim that machine learning provides robust techniques for exploring the predictability of cryptocurrencies and for devising profitable trading strategies in these markets,even under adverse market conditions. 展开更多
关键词 Bitcoin Ethereum Litecoin Machine learning Forecasting TRADING
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Geochemical characteristics and mode of occurrence of trace elements in coal at West Bokaro coalfield 被引量:5
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作者 Sk. Md. Equeenuddin Subhasish Tripathy +1 位作者 Prafuila Kumar Sahoo Amit Ranjan 《International Journal of Coal Science & Technology》 EI 2016年第4期399-406,共8页
The mineralogy and trace element contents in coals from the West Bokaro coalfield, which is the one of the biggest Gondwana coalfields of India, were studied to delineate enrichment of trace elements and their modes o... The mineralogy and trace element contents in coals from the West Bokaro coalfield, which is the one of the biggest Gondwana coalfields of India, were studied to delineate enrichment of trace elements and their modes of occur- rence. Elemental concentrations with reference to their crustal abundances indicated that coals are relatively enriched in As (4.4-15.5 mg/kg), Cd (0.3-3.0 mg/kg), Cu (28.0-68.1 mg/kg) and V (46.6-178.0 mg/kg); depleted in Co (10.8-28.4 mg/ kg), Mn (7.6-483.4 mg/kg), Ni (13.0-31.6 mg/kg), Cr (14.2-85.5 mg/kg) and Zn (5.25-70.4 mg/kg). The concentration of As, Cd, Co, Cu and V were higher than the average values of world and Indian coals. Mineralogical study carried out by X-ray diffraction shows that quartz and kaolinite occur as dominant mineral phases in this coal. Fourier transform infrared spectroscopy pattern suggests organic structures primarily containing aromatic nuclei, aliphatic side chain and some oxygen containing groups. The modes of occurrence of trace elements present in these coals have been determined through statistical approach. Both Cu and Cr are more closely associated with mineral matter, whereas Co is dominantly present with its organic form. The concentrations of Cd, Mn, Ni, Zn, As and V have apparently occur in both organic and inorganic constituents. This study would be helpful to assess the potential environmental impacts during mining and combustion of this coal. 展开更多
关键词 MINERALOGY Organic group Trace elements COAL West Bokaro
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中国科技期刊的发展成就与建设世界一流科技期刊的目标和路径分析 被引量:12
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作者 石红青 《农业图书情报学报》 2021年第7期54-62,共9页
[目的/意义]基于中国科技期刊发展现状及相关研究成果,把握《关于深化改革培育世界一流科技期刊的意见》精神,提出建设世界一流科技期刊的目标和路径,以提升中国科技期刊的世界话语权和影响力。[方法/过程]梳理新中国成立以来中国科技... [目的/意义]基于中国科技期刊发展现状及相关研究成果,把握《关于深化改革培育世界一流科技期刊的意见》精神,提出建设世界一流科技期刊的目标和路径,以提升中国科技期刊的世界话语权和影响力。[方法/过程]梳理新中国成立以来中国科技期刊的发展成就,剖析世界一流科技期刊的特征和内涵,提出建设世界一流科技期刊的具体目标。[结果/结论]要调整科研评价标准,吸引一流论文投稿,要推动科技期刊出版集团化发展,要做精做强中文科技期刊,要加强编辑队伍建设,培养世界一流水平的编辑队伍。 展开更多
关键词 世界一流科技期刊 科研评价标准 期刊联盟 编辑队伍
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Recovery of metals and other beneficial products from coal fly ash: a sustainable approach for fly ash management 被引量:9
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作者 Prafulla Kumar Sahoo Kangjoo Kim +1 位作者 M. A. Powell Sk Md Equeenuddin 《International Journal of Coal Science & Technology》 EI 2016年第3期267-283,共17页
Increasing production and disposal of coal fly ash (CFA) is a matter of serious environment concern. However, CFA contains various beneficial metals and mineral matters whose demand is increasing in the industrializ... Increasing production and disposal of coal fly ash (CFA) is a matter of serious environment concern. However, CFA contains various beneficial metals and mineral matters whose demand is increasing in the industrialized world, while natural supplies are diminishing. Therefore, recovery of these potential resources from CFA can be an alternative way to save mineral resources, as well as to reduce the environmental burden of CFA disposal. There are numerous methods developed for the recovery of beneficial products from CFA. Based on the US patents and journal literatures, the present review describes the recovery status and technologies of major elements such as Al, Si, Fe and Ti, and trace elements such as V, Ga, Ge, Se, Li, Mo, U, Au, Ag, Pt groups and rare earth elements (REEs) and other beneficial products such as magnetic materials, cenospheres, and unburned carbon from CFA. It also highlights the recovery efficiency and drawbacks for their extraction, and suggests future research to develop satisfactory results in terms of selective recovery and purification. 展开更多
关键词 Coal fly ash Beneficial elements RECOVERY Hydrometallurgical methods Extraction efficiency
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Pediatric functional constipation treatment with Bifi dobacterium-containing yogurt:A crossover,double-blind,controlled trial 被引量:26
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作者 Paula VP Guerra Luiza N Lima +5 位作者 Tassia C Souza Vanessa Mazochi Francisco J Penna Andreia M Silva Jacques R Nicoli Elizabet V Guimares 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第34期3916-3921,共6页
AIM: To evaluate the treatment of pediatric functional chronic intestinal constipation (FCIC) with a probiotic goat yogurt. METHODS: A crossover double-blind formula-controlled trial was carried out on 59 students (ag... AIM: To evaluate the treatment of pediatric functional chronic intestinal constipation (FCIC) with a probiotic goat yogurt. METHODS: A crossover double-blind formula-controlled trial was carried out on 59 students (age range: 5-15 years) of a public school in Belo Horizonte, MG, Brazil, presenting a FCIC diagnostic, according to Roma Ⅲ criteria. The students were randomized in two groups to receive a goat yogurt supplemented with 109 colony forming unit/mL Bifidobacterium longum (B.longum) (probiotic) daily or only the yogurt for a period of 5 wk (formula). Afterwards, the groups were intercrossed for another 5 wk. Defecation frequency, stool consistency and abdominal and defecation pain were assessed.RESULTS: Both treatment groups demonstrated improvement in defecation frequency compared to baseline. However, the group treated with probiotic showed most signif icant improvement in the f irst phase of the study. An inversion was observed after crossing over, resulting in a reduction in stool frequency when this group was treated by formula. Probiotic and formula improved stool consistency in the f irst phase of treatment, but the improvement obtained with probiotic was significantly higher (P = 0.03). In the second phase of treatment, the group initially treated with probiotic showed worseningstool consistency when using formula. However, the difference was not signif icant. A signif icant improvement in abdominal pain and defecation pain was observed with both probiotic and formula in the first phase of treatment, but again the improvement was more signif icant for the group treated with B. longum during phase I (P < 0.05). When all data of the crossover study were analyzed, significant differences were observed between probiotic yogurt and yogurt only for defecation frequency (P = 0.012), defecation pain (P = 0.046) and abdominal pain (P = 0.015). 展开更多
关键词 Functional chronic constipation Probiotic Bifi dobacterium longum Yogurt Adolescents Children
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Plant growth and nutrient use efficiency of two native Fabaceae species for mineland revegetation in the eastern Amazon 被引量:1
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作者 Silvio J.Ramos Markus Gastauer +6 位作者 Simone K.Mitre Cecı´lio F.Caldeira Joyce R.Silva Antonio E.Furtini Neto Guilherme Oliveira Pedro W.M.Souza Filho Jose´O.Siqueira 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第6期2287-2293,共7页
The primary challenge of mineland revegetation is the establishment of species able to cope with low availability of nutrients,especially in steep slopes such as of mine pits.We evaluated plant growth response and nut... The primary challenge of mineland revegetation is the establishment of species able to cope with low availability of nutrients,especially in steep slopes such as of mine pits.We evaluated plant growth response and nutrient use efficiency(NUE)of two promising native Fabaceae species(Dioclea apurensis—liana from metalliferous savannas;Bauhinia longipedicellata—tree from Amazon rainforest)from the Caraja´s Mineral Province,eastern Amazon-Brazil.Plants were grown separately in 2-kg pots filled with mining waste.Substrates were fertilized with nitrogen,phosphorus,potassium(NPK),lime,and micronutrients.The results showed increments on growth of both species when nutrients were applied to the mining waste.D.apurensis showed increases in leaf area,plant height,stem diameter,and shoot dry mass production when NPK or NPK?micronutrients were applied,while B.longipedicelata was responsive to application of NPK?lime or NPK?lime?micronutrients.Further,D.apurensis showed higher NUE than B.longipedicelata,especially at the lowest doses of N,P and K.These findings may indicate a substantial advantage of D.apurensis for mineland revegetation,as this species may require lower nutrient inputs,being,therefore,a more sustainable way to revegetate degraded areas. 展开更多
关键词 Fertilizer application Mining soil Tropical forest Nutrient use efficiency
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Slow Pyrolysis of Sugarcane Bagasse for the Production of Char and the Potential of Its By-Product for Wood Protection 被引量:2
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作者 Febrina Dellarose Boer Jérémy Valette +2 位作者 Jean-Michel Commandré Mériem Fournier Marie-France Thévenon 《Journal of Renewable Materials》 SCIE EI 2021年第1期97-117,共21页
Sugarcane bagasse was pyrolyzed using a laboratory fixed bed reactor to produce char and its by-product(pyrolysis liquid).The pyrolysis experiments were carried out using different temperatures(400℃ and 500℃),heatin... Sugarcane bagasse was pyrolyzed using a laboratory fixed bed reactor to produce char and its by-product(pyrolysis liquid).The pyrolysis experiments were carried out using different temperatures(400℃ and 500℃),heating rate(1℃/min and 10℃/min),and holding time(30 min and 60 min).Char was characterized according to its thermal properties,while the pyrolysis liquid was tested for its anti-fungal and anti-termite activities.Pyrolysis temperature and heating rate had a significant influence on the char properties and the yield of char and pyrolysis liquid,where a high-quality char and high yield of pyrolysis liquid can be obtained at a temperature of 500℃ and a heating rate of 10℃/min.The yield of char and pyrolysis liquid was 28.97%and 55.46%,respectively.The principal compounds of pyrolysis liquid were water,acetic acid,glycolaldehyde,1-hydroxy-2-propanone,methanol,formic acid,levoglucosan,furfural,followed by some phenol compounds and guaiacol derivatives.Pyrolysis liquid at a concentration of 0.20%and 0.25%(v/v)caused a 100%inhibition of Coniophora puteana and Trametes versicolor,respectively,when performing inhibition growth tests in Petri dishes.Filter paper treated with 10%of pyrolysis liquid caused 100%of termite mortality,while only 5.65%–7.03%of the treated filter papers consumed by termites at such concentration.Pyrolysis liquid is potentially effective to be used in the formulation of wood protection against fungi and termites. 展开更多
关键词 ANTI-FUNGAL anti-termite biomass CHAR pyrolysis liquid slow pyrolysis sugarcane bagasse VALORIZATION
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Diversity of click beetles in managed nonnative coniferous and native beech stands: Consequences of changes in the structural and species composition of tree stands in Central Europe 被引量:1
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作者 Václav Zumr Oto Nakladal +2 位作者 JiríRemes Tereza Brestovanska Váaclav Zumr 《Forest Ecosystems》 SCIE CSCD 2022年第5期596-605,共10页
The natural composition of forests has undergone significant changes over recent centuries.A closer-to-natural tree species composition has long been perceived as key to a high biodiversity.We investigated the impact ... The natural composition of forests has undergone significant changes over recent centuries.A closer-to-natural tree species composition has long been perceived as key to a high biodiversity.We investigated the impact on communities of click beetles(Elateridae)caused by changes in the tree species composition of spruce monocultures compared to reference sites of recently unmanaged natural beech forests.To collect data,passive interception traps were distributed within managed spruce stands of different age classes and natural beech forests of various developmental stages.The beetle species richness was slightly but not significantly higher in the beech forests.The saproxylic species group was significantly more common in the spruce stands,whereas the group of nonsaproxylic species was significantly more abundant in the beech stands.In the commercial stands,the significantly highest species richness was in the clearings(0–10-year-old stands),and at this forest age class,the vast majority of the beetle species occurred in the spruce stands.In the developmental stages of the natural forest,a slightly higher beetle richness was found at the disintegration stage.The study results suggested that different tree species compositions and stand structures affect the communities of click beetles and substantially change their species composition and thus their response to external influences.Therefore,management of stands using diverse silvicultural systems is recommended for creating diverse ecological niches in forests. 展开更多
关键词 Species richness Forest management Saproxylic beetles Nonsaproxylic beetles Dead wood ELATERIDAE Canopy openness
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桉木浆轻ECF漂白 被引量:1
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作者 Vera Sacon 《国际造纸》 2008年第1期1-4,共4页
VCP是巴西的一家公司,生产各种桉木商品浆和纸产品。VCP采用轻ECF漂白技术,采用较低ClO2用量、氧化合物(H2O2、O2和O3)、苛性钠和热酸的最佳组合进行漂白。热酸段和O3段组合是生产超轻ECF漂白浆的关键。采用含元素氯的漂白程序O(CD)Eop... VCP是巴西的一家公司,生产各种桉木商品浆和纸产品。VCP采用轻ECF漂白技术,采用较低ClO2用量、氧化合物(H2O2、O2和O3)、苛性钠和热酸的最佳组合进行漂白。热酸段和O3段组合是生产超轻ECF漂白浆的关键。采用含元素氯的漂白程序O(CD)EopD生产的漂白浆,其有机氯化物(OCl)含量为300g/t(风干浆)。按规定,标准ECF漂白浆中OCl的含量是200g/t。VCP在其Jacareí工厂有B和C 2条生产线。C生产线采用Oa(Ze)DP漂白程序生产轻ECF漂白浆,其OCl含量为80g/t。B生产线采用OAZDP漂白程序生产超轻ECF漂白浆,其OCl含量低于30g/t。VCP的2条漂白浆生产线废水量大约为8m3/t。ECF、轻ECF和超轻ECF漂白浆机械强度之间没有明显的差异。 展开更多
关键词 ECF漂白 桉木浆 有机氯化物 生产线 CLO2 漂白浆 VCP g/t
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How do altitude and soil properties influence the taxonomic and phylogenetic structure and diversity of Brazilian páramo vegetation? 被引量:5
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作者 Markus GASTAUER Jan THIELE +1 位作者 Stefan POREMBSKI Andreza Viana NERI 《Journal of Mountain Science》 SCIE CSCD 2020年第5期1045-1057,共13页
Altitude and environmental variables such as edaphic properties are considered determinants of species distribution and community composition in mountain ecosystems.Here,we aimed to outline the effects of distinct mou... Altitude and environmental variables such as edaphic properties are considered determinants of species distribution and community composition in mountain ecosystems.Here,we aimed to outline the effects of distinct mountain peaks,altitude and soil properties on community composition,species density,phylogenetic structure and diversity of angiosperm páramo communities from the Serra do Brigadeiro State Park,Minas Gerais,southeastern Brazil.For that,we identified all angiosperm species found in 300 plots(1 m×1 m)from three mountain peaks,measured soil depth and analyzed soil fertility and texture in each plot.To reduce the number of soil variables and species composition,we computed principal coordinates based on soil properties and principal coordinates based on species-plot matrix for each plot.Furthermore,we computed the standard effect sizes of the mean phylogenetic pairwise distance and the mean nearest phylogenetic taxon distance for each plot to investigate differences in the degree of relatedness among coexisting species.We compared differences in response variables between peaks and modelled them in function of altitude and principle components of soil properties using mixed effect models.Species density and phylogenetic diversity differed between peaks,but,contrary to the previous findings,no relationships between species richness or phylogenetic diversity and altitude or soil properties were found,indicating that further investigations are necessary to understand the altitude-biodiversity relationship in Brazilian páramo vegetation.Community composition differed between peaks and depended on altitude,soil properties and interactions between them,indicating that upward shifting of bioclimatic conditions due to climate changes may alter communities of this ecosystem.Phylogenetic structure differed between peaks and was influenced by altitude and soil properties.As phylogenetic clustering increased with altitude,eventual upward movements of species in Brazilian páramo vegetation due to climate change may alter community composition and the degree of relatedness among coexisting species,increasing the risk of species from higher altitudes to disappear.Therefore,conservation priorities arise for higher landscape portions,where these high altitude species may find refuges. 展开更多
关键词 Mountainous ecosystems Altitudebiodiversity relationship High altitude grasslands Phylogenetic diversity Community assemblage Conservation
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Natural enemies depend on remnant habitat size in agricultural landscapes 被引量:1
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作者 Mainara Xavier Jordani erica Hasui Vinicius Xavier da Silva 《Journal of Forestry Research》 CAS CSCD 2015年第2期469-477,共9页
In recent decades,the consequences of habitat fragmentation have been of growing concern,because it is particularly important to understand how fragmentation may affect biodiversity,an ecological service.We tested two... In recent decades,the consequences of habitat fragmentation have been of growing concern,because it is particularly important to understand how fragmentation may affect biodiversity,an ecological service.We tested two hypotheses:(1) that natural fragment size in agricultural landscapes indirectly affects the herbivore through effects on natural predator populations;and(2) predator activity into the crop reduces along the distance from the natural fragment edge.From 2008 and 2009,we conducted our study in seven forest remnants and in surrounding coffee plantations(fragments ranged from 6 to 105 ha,mean 49.28 ± 36.60 ha) in Southern Minas Gerais,Brazil.Birds were sampled by point counts,and insect predation was evaluated by using an artificial insect model(Koh and Menge 2006).Our results suggest that although there were many potential predators(e.g.,wasps,ants,birds,and mammals),birds were the most important taxon unit.The covariance analysis supported the hypothesis that patch size affected the number of larvae predation by overall taxi,but there was no support for a distance effect.These findings suggest that natural enemies’ ecological service(mainly from birds) declined with remnant reduction,which has implications not only for human welfare,but also in strengthening the economic justifications for conserving the remaining natural habitats and biodiversity in agricultural landscapes. 展开更多
关键词 Ecosystem service FRAGMENTATION ISOLATION INSECTIVORE PREDATION
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Piwi like RNA-mediated gene silencing 1 gene as a possible major player in gastric cancer 被引量:1
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作者 Taíssa Araújo Andre Khayat +14 位作者 Luciana Quintana Danielle Calcagno Ronald Mourao Antonio Modesto Juliana Paiva Adhara Lima Fabiano Moreira Edivaldo Oliveira Michel Souza Moneeb Othman Thomas Liehr Eliana Abdelhay Renata Gomes Sidney Santos Paulo Assumpcao 《World Journal of Gastroenterology》 SCIE CAS 2018年第47期5338-5350,共13页
AIM To establish a permanent piwi like RNA-mediated genesilencing 1(PIWIL1) gene knockout in AGP01 gastric cancer cell line using CRISPR-Cas9 system and analyze phenotypic modifications as well as gene expression alte... AIM To establish a permanent piwi like RNA-mediated genesilencing 1(PIWIL1) gene knockout in AGP01 gastric cancer cell line using CRISPR-Cas9 system and analyze phenotypic modifications as well as gene expression alterations.METHODS CRISPR-Cas9 system used was purchased from Dharmacon GE Life Sciences(Lafayette, CO, United States) and permanent knockout was performed according to manufacturer's recommendations. Woundhealing assay was performed to investigate the effect of PIWIL1 knockout on migration capability of cells and Boyden chamber invasion assay was performed to investigate the effect on invasion capability. For the gene expression analysis, a one-color microarray-based gene expression analysis kit(Agilent Technologies, Santa Clara, CA, United States) was used according to the protocol provided by the manufacturer. RESULTS PIWIL1 gene knockout caused a significant decrease in AGP01 migration capacity as well as a significant decrease in cell invasiveness. Moreover, functional analysis based on grouping of all differentially expressed m RNAs identified a total of 35 genes(5 up-regulated and 30 down-regulated) encoding proteins involved in cellular invasion and migration. According to current literature, 9 of these 35 genes(DOCK2, ZNF503, PDE4 D, ABL1, ABL2, LPAR1, SMAD2, WASF3 and DACH1) are possibly related to the mechanisms used by PIWIL1 to promote carcinogenic effects related to migration and invasion, since their functions are consistent with the changes observed(being up-or down-regulated after knockout). CONCLUSION Taken together, these data reinforce the idea that PIWIL1 plays a crucial role in the signaling pathway of gastric cancer, regulating several genes involved in migration and invasion processes; therefore, its use as a therapeutic target may generate promising results in the treatment of gastric cancer. 展开更多
关键词 Gastric cancer Piwi like RNA-mediated gene silencing 1 CRISPR-Cas9 Migration INVASION
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On an Exact Cylindrically Symmetric Solution in a Born-Infeld Type Theory of Gravity 被引量:1
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作者 Tiago de Oliveira Rosa Maria Emilia Xavier Guimarã +1 位作者 es Joaquim Lopes Neto 《Journal of High Energy Physics, Gravitation and Cosmology》 2019年第3期711-718,共8页
In this work, we derive an exact vacuum solution for a cylindrically symmetric metric in an extended gravity theory developed by Novello, De Lorenci and Luciane (hereafter referred to as the NDL theory) which is inspi... In this work, we derive an exact vacuum solution for a cylindrically symmetric metric in an extended gravity theory developed by Novello, De Lorenci and Luciane (hereafter referred to as the NDL theory) which is inspired in the Born-Infeld theory. The main goal of this paper is to nd a cosmic string solution for the NDL theory. However, a careful analysis of the metric shows that it is asymptotically singular and therefore does not represent a cosmic string solution. 展开更多
关键词 Modi ed Theories of GRAVITY TOPOLOGICAL DEFECTS
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