Classification of edible oils by employing 31P and 1H NMR spectroscopy in combination with multivariate statistical analysis. A proposal for the detection of seed oil adulteration in virgin olive oils   总被引：2，自引：0，他引：2  

Vigli G  Philippidis A  Spyros A  Dais P 《Journal of agricultural and food chemistry》2003,51(19):5715-5722

A combination of (1)H NMR and (31)P NMR spectroscopy and multivariate statistical analysis was used to classify 192 samples from 13 types of vegetable oils, namely, hazelnut, sunflower, corn, soybean, sesame, walnut, rapeseed, almond, palm, groundnut, safflower, coconut, and virgin olive oils from various regions of Greece. 1,2-Diglycerides, 1,3-diglycerides, the ratio of 1,2-diglycerides to total diglycerides, acidity, iodine value, and fatty acid composition determined upon analysis of the respective (1)H NMR and (31)P NMR spectra were selected as variables to establish a classification/prediction model by employing discriminant analysis. This model, obtained from the training set of 128 samples, resulted in a significant discrimination among the different classes of oils, whereas 100% of correct validated assignments for 64 samples were obtained. Different artificial mixtures of olive-hazelnut, olive-corn, olive-sunflower, and olive-soybean oils were prepared and analyzed by (1)H NMR and (31)P NMR spectroscopy. Subsequent discriminant analysis of the data allowed detection of adulteration as low as 5% w/w, provided that fresh virgin olive oil samples were used, as reflected by their high 1,2-diglycerides to total diglycerides ratio (D > or = 0.90).  相似文献   

The profile of the Greek 'XXL' family     

Christoforidis A  Batzios S  Sidiropoulos H  Provatidou M  Cassimos D 《Public health nutrition》2011,14(10):1851-1857

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Soil spatial variability and site-specific fertilization maps in an apple orchard     

K. D. Aggelopoulou  D. Pateras  S. Fountas  T. A. Gemtos  G. D. Nanos 《Precision Agriculture》2011,12(1):118-129

In the present study, the spatial variability of some soil physical and chemical properties in a 0.8 ha apple orchard were studied. Sixty soil samples were taken from two sampling depths: 0–0.3 m and 0.3–0.6 m. The soil samples were analyzed for the following soil properties: soil texture, pH, cation exchange capacity and NO₃–N, NH₄–N, P, K, Na, Ca, Mg, Fe, Zn, Mn, Cu, B and organic matter content. Data analysis indicated that most of the nutrients were at sufficient levels. The site-specific application map for N was created based on the amount of N that was removed from the soil with the yield of the previous year. By applying N site-specifically, 38% of N could be saved compared to uniform application.  相似文献   

Optimizing CNC wood milling operations with the use of genetic algorithms on CAM software     

A. A. Krimpenis  N. A. Fountas  T. Mantziouras 《Wood material science & engineering》2016,11(2):102-115

Main focus of this paper is to introduce an appropriate methodology and create a Genetic Algorithm that optimizes wood milling operations, since wood is one of the primary materials used in both structures and musical instruments building. Mechanical properties of wood were considered in the cutting process modeling on CAM software as far as machining parameter values are concerned. Key machining parameters are explained along with their effect on the final product. The proposed Genetic Algorithm was specifically built for wood milling applications and its operators are examined in detail. The undertaken quality characteristics were minimum machining time and optimal surface quality, thus covering both productivity and quality goals at the same time. As a case study, a novel custom 3D CAD model of an electric guitar body was introduced, on which the proposed optimization methodology was implemented, so as to reveal its efficiency and effectiveness.  相似文献   

Metabolic differentiation of diploid and triploid European sea bass juveniles     

Nathanailides  Cosmas  Klaoudatos  Dimitris  Perdikaris  Costas  Klaoudatos  Spyros  Kolygas  Markos  Athanassopoulou  Fotini 《International Aquatic Research》2019,11(2):199-206

International Aquatic Research - The effects of triploidy were studied on indices of growth and metabolism in juvenile European sea bass. Ploidy affected flesh quality of Dicentrachus labrax, as...  相似文献   

The role of communication and co-operation in the adoption of precision farming   总被引：1，自引：0，他引：1  

T. Kutter  S. Tiemann  R. Siebert  S. Fountas 《Precision Agriculture》2011,12(1):2-17

Research on Precision Farming (PF) relates the adoption of PF primarily to economic incentives as well as farm attributes, whereas social factors are commonly ignored. Therefore, the present study analyses the importance of farmers’ communication and co-operation strategies in the adoption of PF and their relation to farm attributes. Forty-nine qualitative interviews with stakeholders from the agricultural sector were conducted. The survey was based in Germany where most interviews took place and reflected with findings from the Czech Republic, Denmark and Greece. It is revealed that farms differ in their communication strategies depending on farm size. Joint investment in PF was only reported from some regions. It can be assumed that agricultural contractors will be major driving forces behind the adoption of PF over the next 10 years, especially in areas with smaller-sized farms. Agricultural data processing by service providers is seen as a common issue. Concerns regarding potential data misuse, over-regulation and software compatibility were raised.  相似文献   

Kinetics of diglyceride formation and isomerization in virgin olive oils by employing 31P NMR spectroscopy. Formulation of a quantitative measure to assess olive oil storage history     

Spyros A  Philippidis A  Dais P 《Journal of agricultural and food chemistry》2004,52(2):157-164

Diacylglycerol isomers and free acidity were determined for five extra virgin olive oils of different initial acidities by employing a facile (31)P NMR methodology as a function of storage time and storage conditions. The kinetic treatment of the hydrolysis of triacylglycerols (TGs) and the isomerization of 1,2-diacylglycerols (1,2-DGs) to 1,3-diacylglycerols (1,3-DGs) during storage of 18 months at ambient temperature in the dark and light and at 5 degrees C in the dark showed that the isomerization is strongly dependent on the rate of the TGs hydrolysis, the initial free acidity (H(0)) of the virgin olive oil samples, and storage conditions. Although the time-evolution of the diacylglycerols (DGs) depends on the TGs hydrolysis, the ratio D of the concentration of 1,2-DGs to the total amount of DGs was found to be independent of this factor. From the kinetic expression of the ratio D, a quantitative measure was formulated that allows the estimation of the storage time or age of virgin olive oils. Application of this quantitative measure to several olive oil samples of known and unknown storage history resulted in a very good agreement with respect to the actual storage time for up to 10-12 months of storage. For a longer storage period, where the isomerization of DGs is close to its equilibrium state, the calculated age index is only indicative.  相似文献   

Yield prediction in apple orchards based on image processing     

A.?D.?AggelopoulouEmail author  D.?Bochtis  S.?Fountas  K.?C.?Swain  T.?A.?Gemtos  G.?D.?Nanos 《Precision Agriculture》2011,12(3):448-456

It has been suggested that apple ( Malus * domestica Borkh) flowering distribution maps can be used for site-specific management decisions. The objectives of this study were (i) to study the flower density variability in an apple orchard using image analysis and (ii) to model the correlation between flower density as determined from image analysis and fruit yield. The research was carried out in a commercial apple orchard in Central Greece. In April 2007, when the trees were at full bloom, photos of the trees were taken following a systematic uniform random sampling procedure. In September 2007, yield mapping was carried out measuring yield per ten trees and recording the position of the centre of the ten trees. Using this data (the measured yield of the trees and the pictures samples, representing the flower distribution), an image processing-based algorithm was developed that predicts tree yield by analyzing the picture of the tree at full bloom. For the evaluation of the algorithm, a case study scenario is presented where the error of the predicted yield was set at 18%. These results indicated that potential yield could be predicted early in the season from flowering distribution maps and could be used for orchard management during the growing season.  相似文献   

Reuse of drainage water in irrigation with the aid of 0-1 linear programming     

Dimitrios Gotsis  Mike Spiliotis  Spyros Giakoumakis 《Irrigation and Drainage Systems》2011,25(4):385-394

Water management for irrigation in areas with high water scarcity includes not only domestic wastewater treatment but also practices for the reuse of drainage water during the irrigation period. The main problem that concerns the reuse of drainage water for irrigation is the accumulation of salts due to the effluents existing in the soil. In this paper an optimization technique is proposed for the management of drainage water that uses, in combination, a soil-water-plant model (SWAP) and a mixed 0-1 linear programming method. The optimization routine was applied to the irrigation network of Alfeios River in Western Greece, an area that is characterized by high precipitation imbalances between winter and summer months.  相似文献   

Agricultural robots—system analysis and economic feasibility   总被引：1，自引：0，他引：1  

S. M. Pedersen  S. Fountas  H. Have  B. S. Blackmore 《Precision Agriculture》2006,7(4):295-308

This paper focuses on the economic feasibility of applying autonomous robotic vehicles compared to conventional systems in three different applications: robotic weeding in high value crops (particularly sugar beet), crop scouting in cereals and grass cutting on golf courses. The comparison was based on a systems analysis and an individual economic feasibility study for each of the three applications. The results showed that in all three scenarios, the robotic applications are more economically feasible than the conventional systems. The high cost of real time kinematics Global Positioning System (RTK-GPS) and the small capacity of the vehicles are the main parameters that increase the cost of the robotic systems.  相似文献