Selection of Peas for Photosynthetic CO 2 Exchange Rate under Field Conditions 1

Crop Science ◽  
1981 ◽  
Vol 21 (4) ◽  
pp. 616-621 ◽  
Author(s):  
J. D. Mahon ◽  
S. L. A. Hobbs
Keyword(s):  
Exchange Rate ◽  
Field Conditions ◽  
Selection Of

scholarly journals Genetic effect in leaf and xylem transcriptome variations among Eucalyptus urophylla x grandis hybrids in field conditions

2018 ◽  
Vol 67 (1) ◽  
pp. 57-65
Author(s):  
Alexandre Vaillant ◽  
Astrid Honvault ◽  
Stéphanie Bocs ◽  
Maryline Summo ◽  
Garel Makouanzi ◽  
...  
Keyword(s):  
Gene Expression ◽  
Variance Components ◽  
Genetic Effect ◽  
Field Conditions ◽  
Eucalyptus Urophylla ◽  
Rna Seq ◽  
Intermediate Phenotypes ◽  
False Discovery ◽  
Hybrid Clones ◽  
Selection Of

Abstract To assess the genetic and environmental components of gene-expression variation among trees we used RNA-seq technology and Eucalyptus urophylla x grandis hybrid clones tested in field conditions. Leaf and xylem transcriptomes of three 20 month old clones differing in terms of growth, repeated in two blocks, were investigated. Transcriptomes were very similar between ramets. The number of expressed genes was significantly (P<0.05) higher in leaf (25,665±634) than in xylem (23,637±1,241). A pairwise clone comparisons approach showed that 4.5 to 14 % of the genes were diffe­rentially expressed (false discovery rate [FDR]<0.05) in leaf and 7.1 to 16 % in xylem. An assessment of among clone variance components revealed significant results in leaf and xylem in 3431 (248) genes (at FDR<0.2) and 160 (3) (at FDR<0.05), respectively. These two complementary approa­ches displayed correlated results. A focus on the phenylpro­panoid, cellulose and xylan pathways revealed a large majo­rity of low expressed genes and a few highly expressed ones, with RPKM values ranging from nearly 0 to 600 in leaf and 10,000 in xylem. Out of the 115 genes of these pathways, 45 showed differential expression for at least one pair of geno­type, five of which displaying also clone variance compo­nents. These preliminary results are promising in evaluating whether gene expression can serve as possible ‘intermediate phenotypes’ that could improve the accuracy of selection of grossly observable traits.

CORROSION INHIBITORS IN OIL AND GAS PRODUCING EQUIPMENT

1972 ◽  
Vol 12 (1) ◽  
pp. 99
Author(s):  
Roy D. Stanphill ◽  
R.W. Gibson
Keyword(s):  
Corrosion Inhibitor ◽  
Corrosion Inhibitors ◽  
Oil And Gas ◽  
Field Conditions ◽  
Screening Tests ◽  
Inhibitor Efficiency ◽  
Organic Corrosion Inhibitor ◽  
The One ◽  
Specific Formulation ◽  
Selection Of

Most internal corrosive conditions found in oil and gas producing equipment can be controlled through the use of corrosion inhibitors. Organic corrosion inhibitor chemistry is now well known and inhibition mechanisms are understood. There are many good inhibitor formulations available today; so many, in fact, that the producer is faced with the problem of selecting the one best suited to his requirements. Many people depend solely on various types of comparative inhibitor efficiency tests in the laboratory to evaluate and select inhibitors for use under field conditions. These tests are important as relative screening tests, but the selection of a carefully planned application program for the specific formulation is equally important.

scholarly journals A comparison of tools and techniques for stabilising UAS imagery for surface flow observations

2021 ◽  
Author(s):  
Robert Ljubičić ◽  
Dariia Strelnikova ◽  
Matthew T. Perks ◽  
Anette Eltner ◽  
Salvador Peña-Haro ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Computational Complexity ◽  
Visual Information ◽  
Rapid Development ◽  
General Purpose ◽  
Surface Flow ◽  
Velocity Estimation ◽  
Field Conditions ◽  
Sensing Applications ◽  
Selection Of

Abstract. While the availability and affordability of unmanned aerial systems (UASs) has led to the rapid development of remote sensing applications in hydrology and hydrometry, uncertainties related to such measurements are still to be quantified and mitigated. Physical instability of the UAS platform inevitably induces motion in the acquired videos and can have a significant impact on the accuracy of camera-based measurements such as velocimetry. A common practice in the data preprocessing stages is the compensation of platform-induced motion by means of digital image stabilisation (DIS) methods, which use the visual information from the captured videos – in the form of physically static features – to first estimate and then to compensate such motion. Most existing stabilisation approaches rely either on in-house built tools based on different algorithms, or on general-purpose commercial software. Intercomparison of different stabilisation tools for UAS remote sensing purposes that could serve as a basis for a selection of a particular tool in given conditions has not been found in the available literature. In this paper we have attempted to summarise and describe several freely available DIS tools applicable to UAS velocimetry purposes. A total of seven tools – six aimed specifically at velocimetry and one general purpose software – were investigated in terms of their (1) stabilisation accuracy in various conditions, (2) robustness, (3) computational complexity, and (4) user experience, using three case study videos with different flight and ground conditions. In attempt to adequately quantify the accuracy of the stabilisation using different tools, we have also presented a comparison metric based on root-mean-squared differences (RMSD) of interframe pixel intensities for selected static features. The most apparent differences between the investigated tools have been found with regards to the method for identifying and selecting static features in videos – manual selection of features or automatic. State-of-the-art methods which rely on automatic selection of features require fewer user-provided parameters and are able to select a significantly higher number of potentially static features (by several orders of magnitude) when compared to the methods which require manual identification of such features. This allows the former to achieve a higher stabilisation accuracy, but manual feature selection methods have demonstrated lower computational complexity and better robustness in complex field conditions. While this paper does not intend to identify the optimal stabilisation tool for UAS-based velocimetry purposes, it does aim to shed a light on implementational details which can help engineers and researchers choose the tool suitable for their needs and specific field conditions. Additionally, the RMSD comparison metric presented in this paper can also be used in order to measure the velocity estimation uncertainty induced by UAS motion.

Replacement of MEG with KHI for Hydrate Control in Subsea Flowline Offshore Myanmar

2021 ◽  
Author(s):  
Jonghyun Kim ◽  
Paolo Scalea ◽  
Chulhwan Hwang ◽  
Jeongmoon Kim
Keyword(s):  
Selection Process ◽  
Field Tests ◽  
Equilibrium Temperature ◽  
Field Application ◽  
Operating Conditions ◽  
Field Conditions ◽  
Gas Industry ◽  
Promising Alternative ◽  
Selection Of

Abstract Objectives/Scope This paper describes the successful replacement of Mono Ethylene Glycol (MEG) by Kinetic Hydrate Inhibitor (KHI) to guarantee flow assurance in the Shwe field subsea production system, offshore Myanmar. It covers the initial difficulties experienced with MEG, specific field conditions, the comprehensive KHI selection process and testing up to field application and operation. Methods, Procedures, Process MEG used for hydrate inhibition in the field's subsea flowline was originally regenerated in the topside facility, however contamination of the MEG with salts from formation water was causing process upsets. The option of installing a reclamation package presented many challenges and, after review of field conditions, the application of a KHI was considered as a promising alternative to MEG. With the engagement of specialist chemical suppliers a broad and challenging series of laboratory, as well as field tests, was carried out to select a suitable product. Finally a dedicated permanent injection skid was installed to guarantee stable KHI delivery and production. Results, Observations, Conclusions The difficulties caused by salt contamination of the MEG system, combined with the intricate field logistics at the remote site offshore Myanmar, entailed a speedy solution. This combined with suitable operating parameters of the field; i.e. low water content, high wellhead flowing temperatures, subcooling within known KHI operating range, ensured KHI was an economical solution. Nevertheless from desktop study to successful field application a series hurdles had to be crossed, including performance and compatibility tests, simulating all the expected Shwe Offshore Platform (SHP) operating conditions: Determination of Hydrate Equilibrium Temperature (HET); Induction Time Autoclave test for the required residence time in the presence of Corrosion Inhibitor (CI); Hot Injection ests at wellhead operating temperature; Thermal stability tests for topsides and condensate disposal system; Umbilical material compatibility tests; Compatibility of KHI with incumbent products (MEG and CI). Testing of a range of products, carried out by specialist chemical supplier, resulted in the selection of a qualified product, followed by a successful field application testing programme. Seven years after its introduction, KHI has helped achieve optimum field uptime and reduced operational costs as well as eased logistics constraints. Novel/Additive Information KHI is not new to the Oil & Gas industry, however information on its selection and application is not widely available. This paper sheds light on the steps to be considered when evaluating KHI as a suitable hydrate inhibitor, as well as the detailed laboratory tests for proper selection of a product. The intent is to help operators who are facing challenges with hydrate inhibition and could revert to KHI as an alternative.

The Real but Limited Influence of Expert Ideas

2009 ◽  
Vol 61 (4) ◽  
pp. 703-730 ◽  
Author(s):  
Johannes Lindvall
Keyword(s):  
Monetary Policy ◽  
Economic Policy ◽  
Exchange Rate ◽  
Strong Influence ◽  
Policy Instruments ◽  
Policy Changes ◽  
Level Of Activity ◽  
Policy Objectives ◽  
The Rich ◽  
Selection Of

A number of influential studies in political science argue that important economic policy changes in the rich democracies since the mid-1970s were caused by the introduction of new economic ideas. This article claims that while experts exert strong influence over the selection of policy instruments, their influence over the formulation of policy objectives is much weaker. In the 1970s, 1980s, and 1990s, the predominance of Keynesianism in Austria and Denmark did not lead Austrian and Danish governments to maintain low unemployment longer than Sweden, where Keynesianism was less strong. But it did lead them to regard fiscal policy as an instrument that can be used to control the level of activity in the economy, while their Swedish counterparts relied instead on exchange rate and monetary policy.

scholarly journals Potential of adjuvants to reduce drift in agricultural spraying

2013 ◽  
Vol 33 (5) ◽  
pp. 986-992 ◽  
Author(s):  
Rone B. de Oliveira ◽  
Ulisses R. Antuniassi ◽  
Alisson A. B. Mota ◽  
Rodolfo G. Chechetto
Keyword(s):  
Wind Tunnel ◽  
Vegetable Oil ◽  
Mineral Oil ◽  
Field Conditions ◽  
Brilliant Blue ◽  
Blue Dye ◽  
Bottom Part ◽  
Wind Tunnel Tests ◽  
Chemical Groups ◽  
Selection Of

The reduction of pesticide spraying drift is still one of the major challenges in Brazilian agriculture. The aim of this study was to evaluate the potential of different adjuvant products, such as surfactants, drift retardants, mineral oil and vegetable oil for reducing drift in agricultural spraying. The experiment consisted of quantifying drift of sprayings of 18 adjuvants dissolved in water under controlled conditions in a wind tunnel. Tests were performed in triplicates with spraying nozzles type Teejet XR8003 VK, pressure of 200kPa and medium drops. Solutions sprayed were marked with Brilliant Blue dye at 0.6% (m v-1). The drift was collected using polyethylene strips transversally fixed along the tunnel at different distances from the nozzle and different heights from the bottom part of the tunnel. Drift deposits were evaluated by spectrophotometry in order to quantify deposits. The adjuvants from chemical groups of mineral oil and drift retardant resulted in lower values of drift in comparison with surfactants and water. The results obtained in laboratory show that the selection of appropriate class and concentration of adjuvants can significantly decrease the risk of drift in agricultural spraying. However, the best results obtained in laboratory should be validated with pesticide under field conditions in the future.

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