86 research outputs found

    Site-specific management of miscanthus genotypes for combustion and anaerobic digestion:A comparison of energy yields

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    In Europe, the perennial C4 grass miscanthus is currently mainly cultivated for energy generation via combustion. In recent years, anaerobic digestion has been identified as a promising alternative utilization pathway. Anaerobic digestion produces a higher-value intermediate (biogas), which can be upgraded to biomethane, stored in the existing natural gas infrastructure and further utilized as a transport fuel or in combined heat and power plants. However, the upgrading of the solid biomass into gaseous fuel leads to conversion-related energy losses, the level of which depends on the cultivation parameters genotype, location, and harvest date. Thus, site-specific crop management needs to be adapted to the intended utilization pathway. The objectives of this paper are to quantify (i) the impact of genotype, location and harvest date on energy yields of anaerobic digestion and combustion and (ii) the conversion losses of upgrading solid biomass into biogas. For this purpose, five miscanthus genotypes (OPM 3, 6, 9, 11, 14), three cultivation locations (Adana, Moscow, Stuttgart), and up to six harvest dates (August-March) were assessed. Anaerobic digestion yielded, on average, 35% less energy than combustion. Genotype, location, and harvest date all had significant impacts on the energy yield. For both, this is determined by dry matter yield and ash content and additionally by substrate-specific methane yield for anaerobic digestion and moisture content for combustion. Averaged over all locations and genotypes, an early harvest in August led to 25%and a late harvest to 45%conversion losses. However, each utilization option has its own optimal harvest date, determined by biomass yield, biomass quality, and cutting tolerance. By applying an autumn green harvest for anaerobic digestion and a delayed harvest for combustion, the conversion-related energy loss was reduced to an average of 18%. This clearly shows that the delayed harvest required tomaintain biomass quality for combustion is accompanied by high energy losses through yield reduction over winter. The pre-winter harvest applied in the biogas utilization pathway avoids these yield losses and largely compensates for the conversion-related energy losses of anaerobic digestion

    Anacardium plants: Chemical,nutritional composition and biotechnological applications

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    Anacardium plants are native to the American tropical regions, and Anacardium occidentale L. (cashew tree) is the most recognized species of the genus. These species contain rich secondary metabolites in their leaf and shoot powder, fruits and other parts that have shown diverse applications. This review describes the habitat and cultivation of Anacardium species, phytochemical and nutritional composition, and their industrial food applications. Besides, we also discuss the secondary metabolites present in Anacardium plants which display great antioxidant and antimicrobial effects. These make the use of Anacardium species in the food industry an interesting approach to the development of green foods.AK. Jugran acknowledges the partial funding from Uttarakhand council for Biotechnology, Pantnagar, Uttarakhand, India (File No. UCB/R&D Project/2018-311) for this work. M. Martorell would like to thank the support offered by CONICYT PIA/APOYO CCTE AFB170007. N. Martins would like to thank the Portuguese Foundation for Science and Technology (FCT-Portugal) for the Strategic project ref. UID/BIM/04293/2013 and ?NORTE2020 - Northern Regional Operational Program? (NORTE-01-0145-FEDER- 000012)

    Environmental Influences on the Growing Season Duration and Ripening of Diverse Miscanthus Germplasm Grown in Six Countries

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    The development of models to predict yield potential and quality of a Miscanthus crop must consider climatic limitations and the duration of growing season. As a biomass crop, yield and quality are impacted by the timing of plant developmental transitions such as flowering and senescence. Growth models are available for the commercially grown clone Miscanthus x giganteus (Mxg), but breeding programs have been working to expand the germplasm available, including development of interspecies hybrids. The aim of this study was to assess the performance of diverse germplasm beyond the range of environments considered suitable for a Miscanthus crop to be grown. To achieve this, six field sites were planted as part of the EU OPTIMISC project in 2012 in a longitudinal gradient from West to East: Wales?Aberystwyth, Netherlands?Wageningen, Stuttgart?Germany, Ukraine?Potash, Turkey?Adana, and Russia?Moscow. Each field trial contained three replicated plots of the same 15 Miscanthus germplasm types. Through the 2014 growing season, phenotypic traits were measured to determine the timing of developmental stages key to ripening; the tradeoff between growth (yield) and quality (biomass ash and moisture content). The hottest site (Adana) showed an accelerated growing season, with emergence, flowering and senescence occurring before the other sites. However, the highest yields were produced at Potash, where emergence was delayed by frost and the growing season was shortest. Flowering triggers varied with species and only in Mxg was strongly linked to accumulated thermal time. Our results show that a prolonged growing season is not essential to achieve high yields if climatic conditions are favorable and in regions where the growing season is bordered by frost, delaying harvest can improve quality of the harvested biomasspublishersversionPeer reviewe

    Advanced model for the calculation of meshing forces in spur gear planetary transmissions

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    This paper presents a planar spur gear planetary transmission model, describing in great detail aspects such as the geometric definition of geometric overlaps and the contact forces calculation, thus facilitating the reproducibility of results by fellow researchers. The planetary model is based on a mesh model already used by the authors in the study of external gear ordinary transmissions. The model has been improved and extended to allow for the internal meshing simulation, taking into consideration three possible contact scenarios: involute–involute contact, and two types of involute-tip rounding arc contact. The 6 degrees of freedom system solved for a single couple of gears has been expanded to 6 + 3n degrees of freedom for a planetary transmission with n planets. Furthermore, the coupling of deformations through the gear bodies’ flexibility has been also implemented and assessed. A step-by-step integration of the planetary is presented, using two typical configurations, demonstrating the model capability for transmission simulation of a planetary with distinct pressure angles on each mesh. The model is also put to the test with the simulation of the transmission error of a real transmission system, including the effect of different levels of external torque. The model is assessed by means of quasi-static analyses, and the meshing stiffness values are compared with those provided by the literature.The authors would like to acknowledge Project DPI2013-44860 funded by the Spanish Ministry of Science and Technology

    Coupling dynamics of a geared multibody system supported by Elastohydrodynamic lubricated cylindrical joints

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    A comprehensive computational methodology to study the coupling dynamics of a geared multibody system supported by ElastoHydroDynamic (EHD) lubricated cylindrical joints is proposed throughout this work. The geared multibody system is described by using the Absolute-Coordinate-Based (ACB) method that combines the Natural Coordinate Formulation (NCF) describing rigid bodies and the Absolute Nodal Coordinate Formulation (ANCF) characterizing the flexible bodies. Based on the finite-short bearing approach, the EHD lubrication condition for the cylindrical joints supporting the geared system is considered here. The lubrication forces developed at the cylindrical joints are obtained by solving the Reynolds’ equation via the finite difference method. For the evaluation of the normal contact forces of gear pair along the Line Of Action (LOA), the time-varying mesh stiffness, mesh damping and Static Transmission Error (STE) are utilized. The time-varying mesh stiffness is calculated by using the Chaari’s methodology. The forces of sliding friction along the Off-Line-Of-Action (OLOA) are computed by using the Coulomb friction models with a time-varying coefficient of friction under the EHD lubrication condition of gear teeth. Finally, two numerical examples of application are presented to demonstrate and validate the proposed methodology.National Natural Science Foundations of China under Grant 11290151, 11221202 and 11002022, Beijing Higher Education Young Elite Teacher Project under Grant YETP1201

    Aniseed

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    This chapter looks at anise (. Pimpinella anisum L.), an annual plant cultivated for its seeds (fruits) and oil. The chapter opens with a description of the plant followed by an examination of its chemical structure. Cultivation area, crop husbandry, including soil conditions, fertilization and harvesting, and post-harvest processing, including storage, irradiation and heat processing, are discussed together with the application of anise as a pest control agent. The chapter covers the main uses of aniseed in food processing and the plant's functional properties and medicinal applications, before concluding with a look at toxicity and allergy and some quality and regulatory issues. © Woodhead Publishing Limited, 2012

    Determination of yield and quality in marjoram as influenced by development periods [Mercanköşk (Majorana hortensis moench)'de gelişme dönemlerine göre verim ve kalite]

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    Marjoram, naturally grown in Mediterranean region, is a perennial shrub. It is used as spices, and its essential oil has also antimicrobial and antibacterial properties. Marjoram is well-adapted to Çukurova conditions, so, the highest fresh (1077.2 kg/da) and dried herba yields (492.9 kg/da) and essential oil yield (7.77 I/da) were obtained at post-flowering stages. The determined main components of its oil were ?-terpinen, p-cymol and terpineol. The contents of geraniol. p-cymol and cineol were found to be influenced by only development stages while sabinen, myrcen, borneol, terpineol, thymol and carvacrol contents were influenced by both development stages and experiment years

    Research on yield, essential oil, contents and components of mint (Mentha) species in different ecologies [Farkli ekolojilerde nane (Mentha) türlerinin verim ile uçucu yag oran ve bileşenlerinin araştirilmasi]

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    Mint oil demand is met by imports in Turkey. For this reason, this study was conducted to determine yields and essential oil contents and components of different Mentha piperita cultivars (M. piperita Ucrainica, M. piperita Mitcham, M. piperita Bulgaristan 36. M. piperita Multimentha. M. piperita Prilubskaja-I) and Mentha species (M. arvensis var. piperascens (L.), M. aquatics. M. spicata ssp. spicata) in Adana and Pozanti ecological conditions over two years. In Adana, they were harvested twice in the first year and once in the second year. In Pozanti. they were harvested once in both years. The total fresh herbage, dry herbage and dry leaf yields in Adana varied from 512.5-4053.8 kg/da. 116.5-1051.8 kg/da and 34.6-431.1 kg/da, respectively. M. piperita Bulgaristan 36 gave the highest herbage yield. In Pozanti. total yields were lower than those of Adana. fresh and dry herbage and dry leaf yields varied from 115.6-678.1, 57.6-322.5 and 17.0-133.0 kg/da, respectively. Essential oil contents varied between 1.57% and 6.29% and were higher than that of pharmacopoeia because of the high temperature, but only M. arvensis had the highest menthol contents (66.2-72.29%) in both years and locations. The menthol contents of Mentha piperita cultivars varied from 6.23% to 40.47%. The carvone content in oil of M. spicata ssp. spicata ranged from 39.38% to 69.41%

    Effect of some plant growth regulators on fruit thinning in apricots [Kaysilarda bazi büyümeyi düzenleyici maddelerin meyve seyreltmesi üzerine etkileri]

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    This study was carried out during 1995-1996 in Çukurova. In the experiment, Priana and Belliana were used as comparative cultivars. In addition, 12.5, 25, 50 ppm of NAA and 500, 1000, 2000, 4000 ppm of carbaryl and 50% of hand thinning were applied about three weeks after full bloom. The results showed that 50 ppm NAA increased both the thinning rate and the fruit size while 1000 and 2000 ppm of carbaryl had a positive effect on the fruit size and weight without having any effect on thinning. Although the treatments gave better results on the fruit size and weight than the control, their effects on the fruit quality criteria varied depending on the cultivars and the doses of the applications. Hormone analysis showed that the level of the plant growth inhibitors was higher than that of the plant growth promoters in all treatments
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