Search results for "riga"
showing 10 items of 700 documents
CO2 uptake of Opuntia ficus-indica (L.) Mill. whole trees and single cladodes, in relation to plant water status and cladode age
2013
Most of net photosynthesis determinations in Opuntia ficus-indica come from measurements on individual cladodes. However, they have limitations when used to scale up to whole canopy gas exchange, because a large variability of carbon assimilation may occur within the canopy, due to, among others, differences in cladode age and intercepted radiation or individual cladode response to abiotic stresses. The aim of this work was to evaluate the application of open gas exchange chambers, simultaneously applied around the whole canopy, to measure net CO 2 uptake, continuously over a 24 h period, in single Opuntia ficus-indica (L.) Mill. potted trees and in relation with their water status. Net CO2…
Response of vine leaf water potential to quick variation in canopy exposure. Example of canopy opening manipulation of Merlot (<em>Vitis vinife…
2004
<p style="text-align: justify;">Plants are in general subject to rapid fluctuations in the environment, particularly as regards the interception of light and therefore water regime. It is important to know the duration and the amplitude of response of the water regime (first leaf water potential) when light interception changes suddenly under natural conditions. widely planted grape variety in the world) was chosen mainly because it offers convenient possibilities of canopy manipulation, ranging from an open and exposed type architecture, to a closed and shaded configurations simply by moving inside or outside a «foldable Lyre» type trellis. Leaf water potential was measured throughou…
Comparative responses of ‘Gala’ and ‘Fuji’ apple trees to deficit irrigation: Placement versus volume effects
2012
Aims: Climate, soil water potential (SWP), leaf relative water content (RWC), stomatal conductance (gs), fruit and shoot growth, and carbohydrate levels were monitored during the 2008 and 2009 growing seasons to study the responses of 'Gala' and 'Fuji' apple trees to irrigation placement or volume. Methods: Three irrigation treatments were imposed, conventional irrigation (CI), partial root-zone drying (PRD, 50% of CI water on one side of the root-zone, which was alternated periodically), and continuous deficit irrigation (DI, 50% of CI water on both sides of the root-zone). Results: After each irrigation season, DI generated twice the soil water deficit (SWDint) than PRD (average of dry an…
Panormus, Poem by D. Carrigan
2010
USING ROTATING SPRINKLER GUNS IN CENTRE‐PIVOT IRRIGATION SYSTEMS †
2019
The use of centre-pivot irrigation systems has significantly increased in the last few decades, since they are easier and less time-consuming to manage compared to other irrigation systems. Standard high-pressure impact sprinklers, low-pressure spray sprinklers or LEPA (Low Energy Precision Application) systems are usually combined with a centre-pivot irrigation system (CP-SYS). However, when applying waste water or with reclaimed effluents that are extremely dirty, small nozzle sizes that require CP-SYS could get plugged. As an alternative to common centre-pivot irrigation systems, this paper analyses the ‘geometry’ of areas irrigated by rotating sprinkler guns in a centre-pivot irrigation…
Centre-pivot irrigation system design for uniform water application rate
2020
&lt;p&gt;In the last few decades, the use of centre-pivot irrigation systems has significantly increased, since it makes farming easier, is more efficient and less time-consuming compared to the other irrigation systems. Several studies have been focused on the hydraulics of the centre-pivot systems. Standard high-pressure impact sprinklers or low-pressure spray sprinklers or Low Energy Precision Application (LEPA) systems are generally mounted on the pipeline.&lt;/p&gt;&lt;p&gt;To ensure the uniformity of water application, the centre-pivot design requires increasing the flow rates along the lateral, because the sprinklers farther from the pivot move faster, and th…
Effects of irrigation on fruit ripening behavior and metabolic changes in olive
2012
Olive (Olea europaea, cv Leccino) fruits grown under different water regimes were analyzed by metabolomics and specific transcript accumulation analyses. The fruit from non-irrigated (rain-fed) and irrigated trees cultivated under field conditions, with a seasonal water amount equivalent to the calculated crop evapotranspiration (ETc) was compared in the last developmental phase and, in particular, at commercial harvest. Metabolomics (GC-MS) analysis identified several hundred metabolites in ripe mesocarp, 46 of which showed significantly different contents in the rain-fed and irrigated samples. Some compounds involved in primary metabolism (carbohydrates, amino acids, organic acids) and se…
Test of multielement analysis of bone samples using instrumental neutron activation analysis (INAA) and anti-Compton spectrometry
1997
INAA and anti-Compton spectrometry has been employed in the analysis of test bone samples. Validity and accuracy of the method were checked by the use of two biological reference materials procured from the National Institute of Standards and Technology, USA (NIST) and the International Atomic Energy Agency, Austria (IAEA). NIST 1486 Bone Meal (ca. 200–800 mg) and A-11 Milk Powder (ca. 200–600 mg) samples were irradiated in the 100 kW TRIGA Mainz reactor. Concentrations of 13 elements in both biological reference materials have been determined and were found in good agreement with the certified and provisional values.
Determination of gunshot residues by neutron activation analysis
1973
Systematic investigations of gunshot residues, deposited around the bullet hole, have been carried out. The traces were produced by firing on filter papers from distances of 5 to 200 cm using one rifle and three pistols as arms. Antimony, lead and barium were quantitatively determined after irradiating the samples in the nuclear reactor TRIGA Mainz by measurement of gamma-lines of122mSb,122Sb,207mPo and139Ba. The determinations were made purely instrumentally and-where the half lives were long enough-also after chemical separation of the nuclides. The amount of the elements were determined in dependence of the firing distance and of the area around the bullet hole.
Development of “New Silk Road” Northern Branch through Seaport of Riga in Latvia
2014
Abstract The study reveals opportunity to develop the “New Silk Road” Northern branch from North-West China (the People's Republic of China) via seaport of Riga in Latvia to Europe. The methods of the study are the monographic method, the statistical analysis, the expert method and a case study. The study shows that the shortest route for the “New Silk Road” Northern branch is through seaport of Riga (Latvia) which is the shortest way from China to the seaport in the European Union. The existing railway infrastructure can be used from Urumqi (North-Western China) to the seaport of Riga. Transit countries for this route are Kazakhstan and Russia. This route could be beneficial for distributi…