Proper water management is a major responsibility of managers of creeping bentgrass grown on putting greens in the hot and humid southern states. The combination of shallow root systems, sand-based root zones, high temperatures, and high evaporative demands frequently results in severe drought stress on bentgrass ( Agrostis palustris Huds.) greens. This study was initiated to determine the effects of irrigation frequency on creeping bentgrass turgor pressure and on the O 2 and CO 2 concentrations in a sand-based root zone mixture. In total, 81 plots, 1.5 × 1.5 m each, were established on a USGA-type root zone mixture and organized into 9 groups of 9 plots each. Each group could be irrigated individually. One plot in each group was planted to either `A-4', `Crenshaw', `Mariner', `L-93', or `Penncross' creeping bentgrass. Irrigation frequency treatments of 1-, 2-, and 4-day replacement of historical PET were imposed on three groups each. After establishment, measurements of the leaf water potential, osmotic potential, soil oxygen concentration, and soil carbon dioxide concentrations were made over a 1- to 2-year period. Bentgrass irrigated every 1 or 2 days had significantly ( P = 0.05) greater turgor pressures at 0600 hr as compared to turf irrigated every 4 days in 1997. No differences were seen in 1998 due to drier environmental conditions. Concentrations of O 2 and CO 2 in the soil air remained in the optimal range for all treatments, indicating that lack of O 2 in the root zone as a result of frequent irrigation may not be the primary cause for reduced rooting depth of bentgrass grown on highly permeable sand-based root zone mixtures.

The culture of creeping bentgrass (Agrostis palustris Huds.) at low mowing heights on putting greens in the hot humid region of the USA presents numerous water management problems. Frequent irrigation of greens to prevent water stress has been credited with producing shallow rooted turf with reduced tolerance to environmental stress. The present study was conducted to determine the relationship between irrigation frequency and turf quality, shoot density, and root length density for five cultivars of creeping bentgrass grown on a sand‐based root zone and maintained to putting green standards. A total of 81 plots, 1.5 by 1.5 m each, were established on a USGA‐type root zone mixture and organized into nine irrigation cells of nine plots each. Each irrigation cell could be irrigated individually. One plot in each irrigation cell was planted to the following bentgrass cultivars: A‐4, Crenshaw, Mariner, L‐93, and Penncross. The remaining four plots in each irrigation cell were also planted with bentgrass but were not a part of this study. Irrigation frequency treatments of 1‐, 2‐, and 4‐d were imposed on three irrigation cells each. After establishment, measurements of turf quality, shoot density and root length density were made over a 2‐yr period. In both years, Crenshaw and L‐93 had the best turf quality. At the end of the study, shoot densities for Crenshaw, L‐93, and A‐4 were 37 to 42% greater than Mariner and Penncross. Because of frequent rainfall events in 1997, there were no significant (P ≤ 0.05) effects of irrigation frequency on shoot density or root length density. However, in 1998, turf was more dependent on irrigation and bentgrass irrigated every 4 d had significantly greater turf quality, shoot density, and root length density than that watered every 1 or 2 d. The data show that even under putting green management conditions, reduced irrigation frequency of bentgrass produces a larger and deeper root system resulting in greater overall plant health, turf quality, and shoot density.

AbstractThis paper describes experiences in structuring software for an aircraft ‘flying laboratory’ used in a variety of scientific experiments in the areas of geophysics, oceanography and advanced navigation. The software is required to operate in a hard real‐time fashion, processing a number of streams of sampled sensor data within the time interval defined by corresponding periodic sampling clocks.The operational software for this system is structured into a number of real‐time periodic processes which are executed under the control of a real‐time kernel developed for this environment. Both the scheduler used in the real‐time kernel and the structuring of the various processes in the system are described in detail. Various other aspects of the system along with experiences gained over a development life cycle are noted.

Chemischer InformationsdienstVolume 5, Issue 6 Physical Organic Chemistry ChemInform Abstract: STRUCTURE OF 2-ALKANONYL RADICALS PART 3, ELECTRON PARAMAGNETIC RESONANCE STUDY OF RADICALS PRODUCED BY X-IRRADIATION OF ALIPHATIC KETONES IN ADAMANTANE D. M. CAMAIONI, D. M. CAMAIONISearch for more papers by this authorH. F. WALTER, H. F. WALTERSearch for more papers by this authorJ. E. JORDAN, J. E. JORDANSearch for more papers by this authorD. W. PRATT, D. W. PRATTSearch for more papers by this author D. M. CAMAIONI, D. M. CAMAIONISearch for more papers by this authorH. F. WALTER, H. F. WALTERSearch for more papers by this authorJ. E. JORDAN, J. E. JORDANSearch for more papers by this authorD. W. PRATT, D. W. PRATTSearch for more papers by this author First published: February 12, 1974 https://doi.org/10.1002/chin.197406059Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume5, Issue6February 12, 1974 RelatedInformation

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTStructure of 2-alkanonyl radicals. III. Electron paramagnetic resonance study of radicals produced by x-irradiation of aliphatic ketones in adamantaneD. M. Camaioni, H. F. Walter, J. E. Jordan, and D. W. PrattCite this: J. Am. Chem. Soc. 1973, 95, 24, 7978–7992Publication Date (Print):November 1, 1973Publication History Published online1 May 2002Published inissue 1 November 1973https://pubs.acs.org/doi/10.1021/ja00805a009https://doi.org/10.1021/ja00805a009research-articleACS PublicationsRequest reuse permissionsArticle Views69Altmetric-Citations39LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTFertilizer Granulation, Effect of Particle Size of Raw Materials on Granulation of FertilizersA. B. Phillips, G. C. Hicks, J. E. Jordan, and T. P. HignettCite this: J. Agric. Food Chem. 1958, 6, 6, 449–453Publication Date (Print):June 1, 1958Publication History Published online1 May 2002Published inissue 1 June 1958https://pubs.acs.org/doi/10.1021/jf60088a002https://doi.org/10.1021/jf60088a002research-articleACS PublicationsRequest reuse permissionsArticle Views103Altmetric-Citations6LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts