scholarly journals Long-Term Yield and Quality Performance of Perennial Energy Grasses (Agropyron spp.) on Marginal Land

Agronomy ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 1051
Author(s):  
Carlos S. Ciria ◽  
Ruth Barro ◽  
Marina Sanz ◽  
Pilar Ciria
Keyword(s):  
Point Of View ◽  
Perennial Grasses ◽  
Marginal Land ◽  
Agropyron Elongatum ◽  
Quality Performance ◽  
Yield And Quality ◽  
Use Efficiency ◽  
Rain Use Efficiency ◽  
Energetic Point ◽  
Alkali Elements

The cultivation of perennial grasses is one of the most desirable alternatives as energy feedstock, but it is difficult to achieve competitive yields under Mediterranean marginal conditions. The aim of this study was to assess the performance of three cool-season grasses (Agropyron spp.) from an agronomic and energetic point of view by comparing the dry matter (DM) yields, rain use efficiency, chemical composition, and biomass quality over an eight-year period in Spain under marginal rainfed conditions. The tall wheatgrass (Agropyron elongatum (Host) Beauv.) cultivars, Alkar (4.8 Mg DM·ha−1) and Jose (4.7 Mg DM·ha−1), achieved the highest yields. Productions below 0.5 Mg DM·ha−1 were obtained when rainfall was lower than 150 mm between March and June. The biomass obtained from the tested grasses showed relatively high contents of ash, silicon, and alkali elements. Net calorific values ranged between 16.7 and 18.5 MJ·kg−1 db. Differences in the composition among species and cultivars are not likely to affect their combustion behavior from a practical point of view. The ash content, as well as the concentrations of K, S, Na, and Cl, tended to decrease over the years. The results offered would be very useful for the implementation of this type of crop in marginal land.

scholarly journals Zinc Uptake by Plants as Affected by Fertilization with Zn Sulfate, Phosphorus Availability, and Soil Properties

Agronomy ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 390
Author(s):  
Ramiro Recena ◽  
Ana M. García-López ◽  
Antonio Delgado
Keyword(s):  
Soil Properties ◽  
Zn Deficiency ◽  
Acid Extraction ◽  
P Availability ◽  
Positive Role ◽  
Yield And Quality ◽  
Zn Uptake ◽  
Use Efficiency ◽  
Crystalline Oxides ◽  
Zn Availability

Zinc (Zn) deficiency constrains crop yield and quality, but soil factors influencing Zn availability to plants and reactions of applied Zn fertilizer are not fully understood. This work is aimed at studying Zn availability in soil and the use efficiency of Zn fertilizers by plants as affected by soil properties and particularly by soil available P. We performed a pot experiment involving four consecutive crops fertilized with Zn sulfate using 36 soils. The cumulative Zn uptake and dry matter yield in the four crops increased with increased initial diethylenetriamine pentaacetic acid extraction of Zn (DTPA-Zn) (R2 = 0.75 and R2 = 0.61; p < 0.001). The initial DTPA-Zn increased with increased Olsen P (R2 = 0.41; p < 0.001) and with increased ratio of Fe in poorly crystalline to Fe in crystalline oxides (R2 = 0.58; p < 0.001). DTPA-Zn decreased with increased cumulative Zn uptake, but not in soils with DTPA-Zn < 0.5 mg kg−1. Overall, the available Zn is more relevant in explaining Zn uptake by plants than applied Zn sulfate. However, in Zn-deficient soils, Zn fertilizer explained most of the Zn uptake by crops. Poorly crystalline Fe oxides and P availability exerted a positive role on Zn availability to plants in soil.

scholarly journals Photochemistry of 1-Phenyl-4-Allyl-Tetrazol-5-One: A Theoretical Study Contribution towards Mechanism Elucidation

2021 ◽  
Vol 11 (9) ◽  
pp. 4045
Author(s):  
Amilcar Duque-Prata ◽  
Carlos Serpa ◽  
Pedro J. S. B. Caridade
Keyword(s):  
Density Functional ◽  
Reaction Pathway ◽  
Intramolecular Proton Transfer ◽  
Polarizable Continuum Model ◽  
Uv Spectra ◽  
Point Of View ◽  
Basis Set ◽  
Pathway Evolution ◽  
Photodegradation Mechanism ◽  
Energetic Point

The photodegradation mechanism of 1-phenyl-4-allyl-tetrazol-5-one has been studied using (time-dependent) density functional theory with the M06-HF, B3LYP, and PBE0 functionals and the VDZ basis set. All calculations have been carried out using the polarizable continuum model to simulate the solvent effects of methanol. The reaction pathway evolution on the triplet state has been characterised to validate a previously postulated experimental-based mechanism. The transition states and minimums have been initially located by local scanning in partial constrained optimisation, followed by a fully relaxed search procedure. The UV spectra has shown to be better described with PBE0 functional when compared with the experimental results, having the M06-HF a shift of 40 nm. From the energetic point of view, the postulated mechanism has been validated in this work showing a concerted photoextrusion of the N2 molecule. The intramolecular proton transfer occurs at a later stage of the mechanism after cyclization of the allyl group on a triplet biradical intermediate. The photoproduct observed experimentally, a pyrimidinone, has been characterised. The infrared spectroscopic reaction profile has also been proposed.

scholarly journals Continuous Lighting and High Daily Light Integral Enhance Yield and Quality of Mass-Produced Nasturtium (Tropaeolum majus L.) in Plant Factories

Plants ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1203
Author(s):  
Wenshuo Xu ◽  
Na Lu ◽  
Masao Kikuchi ◽  
Michiko Takagaki
Keyword(s):  
Secondary Metabolites ◽  
Mass Production ◽  
Physiological Stress ◽  
Growth Parameters ◽  
Leaf Production ◽  
High Productivity ◽  
Artificial Lighting ◽  
Yield And Quality ◽  
Use Efficiency ◽  
Tropaeolum Majus

Nasturtium (Tropaeolum majus L.), as a medicinal plant, has a high phenolic content in its leaves and flowers. It is often used in salads as a dietary vegetable. Attracting strong demand, it could be a good candidate crop for a plant factory with artificial lighting (PFAL) that can achieve the mass production of high-quality crops with high productivity by regulating environmental conditions such as light. In this study, two experiments were conducted to investigate the effects of continuous lighting (CL) and different daily light integrals (DLIs) under CL on the growth, secondary metabolites, and light use efficiency (LUE) of nasturtium, all of which are essential in the successful cultivation in PFALs. In Experiment 1, two lighting models, the same DLI of 17.3 mol m-2 d-1 but different light periods (24 and 16 h) with different light intensities (200 and 300 µmol m−2 s−1, respectively), were applied to nasturtium. The results showed that leaf production, secondary metabolites, and LUE were higher under the 24-h CL treatment than under the 16-h non-CL treatment. In Experiment 2, three DLI levels (17.3, 25.9, and 34.6 mol m-2 d-1) under the CL condition were applied. The results showed that the growth parameters were positively correlated with the DLI levels under CL. The lowest DLI had the highest LUE. We conclude that the mass production of nasturtium under CL in PFALs is feasible, and the yield increases as DLI increases from 17.3 to 34.6 mol m-2 d-1 under CL without causing physiological stress on plants.

scholarly journals A Comprehensive Review on Sustainable Industrial Vertical Farming Using Film Farming Technology

2020 ◽  
Vol 10 (1) ◽  
pp. 46
Author(s):  
Zitian Zhang ◽  
Michel Rod ◽  
Farah Hosseinian
Keyword(s):  
Population Growth ◽  
Water Use ◽  
Cost Benefit Analysis ◽  
Arable Land ◽  
Cost Benefit ◽  
Yield Increase ◽  
Vertical Farming ◽  
Yield And Quality ◽  
Use Efficiency ◽  
Global Population

Rapid population growth is expected to lead to the global population reaching 8.9 billion by 2050. In order to sustain such population growth, global food production must grow more than 70% by 2050. Arable land per capita, however, is on the decline. Vertical farming (VF) provides an enterprising solution to these concerns. VF utilizes stacked levels of growing racks and beds to maximize grow space per square foot of land and typically uses hydroponics to reduce water use. Similarly, film farming (FF) is a new agricultural technique developed in Japan for the soilless cultivation of crops while drastically reducing water use. FF has the potential to be integrated into VF systems to improve water use efficiency, and further improve food safety. This, however, relies on the possible improvements in yield and plant quality to increase sales volume and price to offset the added cost of FF. This review illustrates a cost-benefit analysis of a theoretical VF to show the yield increase and price point needed for FF integration to be viable as 27 247 kg (43.57%) and $9.67/kg (26.90%) respectively. This review also shows the benefits to yield and quality is enough for the integration to be viable.

scholarly journals A 6-Components Mechanistic Model of Cutting Actions in Milling

2021 ◽  
Author(s):  
Maël Jeulin ◽  
Olivier Cahuc ◽  
Philippe Darnis ◽  
Raynald Laheurte
Keyword(s):  
Energy Balance ◽  
Experimental Model ◽  
Cutting Forces ◽  
Mechanistic Model ◽  
Cutting Parameters ◽  
Point Of View ◽  
Stress Fields ◽  
Mechanistic Modelling ◽  
Cutting Zone ◽  
Energetic Point

Abstract Most of the cutting models developed in the literature attest only to the presence of cutting forces in the balance of mechanical actions resulting from cutting. However, several studies have highlighted the presence of cutting moments during machining, and particularly 3D cutting in milling. The objective of this paper is to characterise phenomena associated with cutting moments by performing experimental mechanistic modelling in 3D cutting. For this purpose, several modelling factors will be investigated, such as the 3D cutting reference frame, the undeformed chip section, the cutting parameters, the cutting zone, etc. The predictive model of this study proves to be relatively efficient for an experimental model and allows a global prediction of cutting moments in milling. Furthermore, beyond the aspect of stress fields in the workpiece caused by cutting moments, this paper gives perspectives from an energetic point of view for which the share of moments in the energy balance could be substantial for monobloc tools.

scholarly journals YIELD OF PERENNIAL GRASSES AND SOIL FERTILITY OF SOD-PODZOLIC SOIL IN CASE OF LONG-TERM APPLICATION OF MINERAL FERTILIZERS

2021 ◽  
Vol 250 ◽  
pp. 71-77
Author(s):  
A. Yu. Gavrilova ◽  
◽  
A. M. Konova ◽  
Keyword(s):  
Perennial Grasses ◽  
Mineral Fertilizers ◽  
Yield And Quality ◽  
Mobile Forms ◽  
Unit Dose ◽  
Phosphorus And Potassium ◽  
Higher Doses ◽  
Positive Effect

The article considers the effect of increasing doses and various combinations of mineral fertilizers applied to the cover crop on the yield and quality of a mixture of perennial grasses of two - years use, as well as the effect of fertilizers on the agrochemical parameters of sod-podzolic light loamy soil. The objects of the study were Stodolich meadow clover and Leningradskaya 204 meadow timothy grass. The studies were carried out in two crop rotations - with standard and reduced single doses of mineral fertilizers. The research results showed that in the years (VIII rotation) when the unit dose of fertilizers was increased to N20P20K25, the yield of perennial grasses was higher compared to the harvest in the VII rotation. The most appropriate dose in the VII rotation on perennial grasses of the 1st year was N30P30K45, on grasses of the 2nd year - doses of N30P30K45 and N40P40K60. In the VIII rotation, the highest yield of perennial grasses of the 1st year of use was obtained at a dose of N160P160K200 (8.4 t / ha), of grasses of the 2nd year of use at doses of N80P80K100 and N100P100K125 (6.5 t / ha). Positive effect of increasing doses of mineral fertilizers on the content of soil organic matter has been noted. On the contrary, the soil acidity increased from 4.7 to 4.3 units with an increase of mineral doses. Higher doses of fertilizers increased the content of mobile forms of phosphorus and potassium in the soil.

Investigation on the Intake Process for a Theoretical Twin Opposite Piston Compressor Using R744 Refrigerant

2016 ◽  
Vol 823 ◽  
pp. 75-78
Author(s):  
Doru Groza ◽  
Dan Mihai Dogariu
Keyword(s):  
Air Conditioning ◽  
Piston Compressor ◽  
Environmental Issues ◽  
Point Of View ◽  
Vapor Compression ◽  
Household Appliances ◽  
Intake Process ◽  
Vapor Compression Refrigeration ◽  
Energetic Point ◽  
Air Conditioning Systems

This study aims to validate the use of R744 for a resonant twin piston compressor for domestic applications. The vapor-compression refrigeration is the most commonly approached method for cooling household appliances such as refrigerators and air conditioning systems. The R134a refrigerant is one of the most suitable refrigerants from an energetic point of view. R744 (CO2) compressors are less efficient, but the fact that the R134a raises serious environmental issues pushes commercial trend towards the usage of R744 [1]-[3]. Use of R744 in household appliances is currently an open topic and no company has switched yet to the environmental-friendly alternative. In this paper the fill efficiency will be simulated in order to validate if a conventional compressor such as the opposite twin piston compressor is capable of filling with refrigerant when operating at a 50Hz frequency. Such a validation can enable further investigations regarding the replacement of R134a with R744.

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