Corrosion and performance of dust palliatives : laboratory and field studies

2021 ◽  
Author(s):  
Lulu Edwards ◽  
Charles Weiss ◽  
J. Newman ◽  
Fred Nichols ◽  
L. Coffing ◽  
...  
Keyword(s):  
Field Experiments ◽  
Field Studies ◽  
Field Trials ◽  
Ground Vehicle ◽  
Wind Speeds ◽  
Corrosion Studies ◽  
Air Impingement ◽  
And Performance ◽  
Rotary Wing

This report details laboratory and field experiments on BioPreferred® dust suppressants to assess performance and corrosion characteristics. Numerous bio-based dust suppressant products are marketed, but little data are available to assess performance for dust abatement and corrosion of common metals. A laboratory study used an air impingement device and the Portable In-Situ Wind ERosion Laboratory (PI-SWERL) to simulate wind speeds similar to those in field conditions for rotary wing aircraft. Laboratory corrosion studies used metal coupons imbedded in soil treated with dust palliative. Field trials were conducted using ground vehicle traffic to minimize cost and lower safety concerns while increasing surface wear from repetitive traffic. These studies clearly show that bio-based products demonstrate low corrosion potential with similar dust abatement performance to synthetic-based agents.

scholarly journals Optimizing Sowing Depth of Tef for Irrigated Mediterranean Conditions: From Laboratory to Field Studies

Agronomy ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1983
Author(s):  
Shiran Ben-Zeev ◽  
Shane Kerzner ◽  
Onn Rabinovitz ◽  
Yehoshua Saranga
Keyword(s):  
Field Experiments ◽  
Field Studies ◽  
Field Trials ◽  
Eragrostis Tef ◽  
Sowing Depth ◽  
New Crops ◽  
Different Depths ◽  
Plant Emergence ◽  
Increasing Demand ◽  
Mediterranean Conditions

Developing new crops adapted to arid conditions is a promising approach to meet the increasing demand for food production under expanding aridity. Tef [Eragrostis tef (Zucc.) Trotter] is a C4 cereal crop cultivated mainly in Ethiopia and the Horn of Africa, and known for its high resilience to stressful environments. Due to their tiny size, tef seeds are traditionally sown by broadcasting and lightly covering with soil. Under semiarid Mediterranean conditions, a deeper sowing may guarantee seedling establishment while saving on irrigation water. The objective of this study was, therefore, to determine the effects of sowing depth on tef emergence, development, lodging, and productivity. Tef seeds were sown at different depths in test tubes and pots, and in two field experiments. In tubes and pots, time from sowing to emergence increased about twofold and emergence rate decreased in the deepest sowing (3 cm) treatment compared to controls (0 cm). In the pot and field trials, deep sowing (3 cm) significantly reduced plant height, shoot and root biomass, and lodging. Sowing depths of 1–2 cm allowed successful plant establishment while not exacting penalties on plant emergence or development; hence this range appears to be optimal for sowing irrigated tef.

Fertilization biology of the abalone Haliotis laevigata: laboratory and field studies

1999 ◽  
Vol 56 (9) ◽  
pp. 1668-1678 ◽  
Author(s):  
Russ Babcock ◽  
John Keesing
Keyword(s):  
Field Experiments ◽  
Nearest Neighbor ◽  
Field Studies ◽  
Fertilization Success ◽  
Limiting Factor ◽  
Fertilization Rates ◽  
Abalone Species ◽  
Nearest Neighbor Distances

A combination of laboratory and field experiments with the commercial abalone species Haliotis laevigata showed that fertilization may be a limiting factor in some exploited populations when distances separating spawning individuals are too large. The effects of gamete age, gamete concentration, and gamete contact time in the laboratory were used to model fertilization success in situ and compared with experimental fertilization rates in the field. Highest fertilization rates in vitro (80%) were found for sperm concentrations in the range of 1 × 104 to 1 × 106·mL-1. Fertilization rates of 48 ± 1.7% (95% CI) were measured at separation distances of 2 m and dropped to 2.8 ± 0.7% (95% CI) at 16 m downstream, agreeing closely with rates predicted by the model. Recruitment failures reported for South Australian populations of H. laevigata have occurred when densities fell below ca.0.3 animals·m-2, or mean nearest-neighbor distances between 1 and 2 m. This density corresponds well to critical nearest-neighbor distances for fertilization success. Stocks at higher densities are predicted to have higher fertilization rates (ca.90%) such that fertilization success is not a factor limiting recruitment.

scholarly journals Development of Strategies to Evaluate Brassica oleracea L. Vegetable Crops for Wirestem Caused by Rhizoctonia solani

HortScience ◽  
1996 ◽  
Vol 31 (4) ◽  
pp. 621c-621
Author(s):  
Mark W. Farnham ◽  
Anthony P. Keinath
Keyword(s):  
Rhizoctonia Solani ◽  
Field Experiments ◽  
Effective Means ◽  
Field Studies ◽  
Field Trials ◽  
Alternative Methods ◽  
Environment Interaction ◽  
Vegetable Crops ◽  
Respective Field ◽  
Controlled Environments

Wirestem, caused by Rhizoctonia solani, is a destructive disease of B. oleracea cole crops and is distributed worldwide. Effective means of wirestem control include soil fumigation and soil treatment with pentachloronitrobenzene, which are increasingly expensive and environmentally undesirable. As a consequence, alternative methods of wirestem control are needed. Thus, we conducted controlled-environment and field experiments to develop methodology to study host-plant resistance and possibly biocontrol agents as potential wirestem control alternatives. Seedlings of 12 cultivars (three each of cauliflower, broccoli, cabbage, and collard) at the four- to five-leaf stage were transplanted to trays in a growth room or into field plots and covered with soil infested with R. solani AG-4 sclerotia. Disease progression (percent of plants healthy, diseased, and dead) was observed every 3 days for 2 weeks in the controlled environments and for 3 weeks in field trials. At the end of two studies, plants were dug with roots intact and rated for disease using a 1 to 10 scale. In all trials, percent healthy plants stabilized at about 2 weeks after inoculation. Incidence of wirestem disease varied among experiments ranging from 70% to 100% diseased, dead plants in controlled environments, and from 51% to 88% and 33% 65% in the two respective field studies. Disease rating was always negatively and significantly correlated with percent healthy plants. Although a genotype × environment interaction was observed, some cultivars (i.e., `Snowcone' and `Snowcrown' cauliflowers) were always severely diseased, while others (i.e., `Viking' broccoli and `Blue Max' collard) were consistently among the least diseased.

Assessing the performance of urban BMPs in Scotland

1999 ◽  
Vol 39 (12) ◽  
pp. 123-131 ◽  
Author(s):  
C. Jefferies ◽  
A. Aitken ◽  
N. McLean ◽  
K. Macdonald ◽  
G. McKissock
Keyword(s):  
Best Management Practices ◽  
Urban Areas ◽  
Management Practices ◽  
Field Studies ◽  
Source Control ◽  
Urban Drainage ◽  
Best Management ◽  
Different Depths ◽  
And Performance

Best Management Practices (BMPs) in urban drainage have been promoted in Scotland for a number of years in response to the need to combat pollution arising from diffuse sources in urban areas. This has led to the construction of around one hundred BMP installations using both source and end of pipe control. These are principally in the East of Scotland, and the number is growing rapidly as education and knowledge increases. A programme of investigations into the factors which influence the performance of the systems commenced in 1997. A range of types of BMP are under study including both source control and end of pipe systems. The sites have been divided into groups for which different depths of investigation are being undertaken. The programme involves a number of parallel investigations requiring field studies, data reviews and enquiries to confirm applicability and performance in situ. Many of the factors which influence the selection, installation and operation of a particular system are social, legal and administrative in addition to those which relate to its design and construction. The different strands of the study have been developed to ensure that all influences are identified and evaluated.

scholarly journals Microbubbles as Proxies for Oil Spill Delineation in Field Tests

2021 ◽  
Vol 9 (2) ◽  
pp. 126
Author(s):  
Yaomei Wang ◽  
Worakanok Thanyamanta ◽  
Craig Bulger ◽  
Neil Bose ◽  
Jimin Hwang
Keyword(s):  
Residence Time ◽  
Field Experiments ◽  
Oil Spills ◽  
Autonomous Underwater Vehicles ◽  
Field Tests ◽  
Field Trials ◽  
Bubble Plumes ◽  
Acoustic Methods ◽  
Long Endurance

To overcome the environmental impacts of releasing oil into the ocean for testing acoustic methods in field experiments using autonomous underwater vehicles (AUVs), environmentally friendly gas bubble plumes with low rise velocities are proposed in this research to be used as proxies for oil. An experiment was conducted to test the performance of a centrifugal-type microbubble generator in generating microbubble plumes and their practicability to be used in field experiments. Sizes of bubbles were measured with a Laser In-Situ Scattering and Transmissometry sensor. Residence time of bubble plumes was estimated by using a Ping360 sonar. Results from the experiment showed that a larger number of small bubbles were found in deeper water as larger bubbles rose quickly to the surface without staying in the water column. The residence time of the generated bubble plumes at the depth of 0.5 m was estimated to be over 5 min. The microbubble generator is planned to be applied in future field experiments, as it is effective in producing relatively long-endurance plumes that can be used as potential proxies for oil plumes in field trials of AUVs for delineating oil spills.

Controlling Bamboo (Phyllostachys spp.) with Herbicides

2007 ◽  
Vol 21 (1) ◽  
pp. 80-83 ◽  
Author(s):  
Mark A. Czarnota ◽  
Jeffrey Derr
Keyword(s):  
Field Experiments ◽  
Field Studies ◽  
Field Trials ◽  
Grass Species ◽  
Bamboo Shoot ◽  
Bamboo Species ◽  
Limited Information ◽  
Single Application ◽  
Fresh Weight ◽  
Greenhouse Experiments

Bamboos are grass species that can escape cultivation and invade lawns, landscapes, and other areas. Limited information is available on ways to control invasive bamboo species. Greenhouse and field studies were initiated to determine the level of bamboo control provided by a single application of selected PRE and POST herbicides. Bamboo species included in the study were golden bamboo in greenhouse experiments and red-margined bamboo in field experiments. In greenhouse trials, MSMA, quinclorac, dithiopyr, clethodim, fenoxaprop, and sethoxydim did not control either species. Glyphosate, glufosinate, and fluazifop significantly reduced bamboo-shoot fresh weight, although regrowth occurred after a single application. In field trials, bamboo control with dichlobenil in the 2002 and 2004 experiments was less than 23%. For the study initiated in 2002, glyphosate and imazapyr provided 76% and 98% bamboo control, respectively, at 58 wk after treatment (WAT). By 161 WAT (approximately 3 yr after treatment), bamboo-control ratings were 40% with glyphosate and 85% with imazapyr. For the study initiated in 2004, at 61 WAT, glyphosate and imazapyr provided 46 and 88% control of bamboo, respectively.

Host Plant Recognition and Performance of Klambothrips myopori (Thysanoptera: Phlaeothripidae) Across Myoporum Cultivars in Southern California

2019 ◽  
Vol 112 (4) ◽  
pp. 1645-1650
Author(s):  
Christopher J Shogren ◽  
Timothy D Paine
Keyword(s):  
Host Plants ◽  
Urban Landscape ◽  
Field Studies ◽  
Field Trials ◽  
Suitable Host ◽  
Complete Development ◽  
Plant Recognition ◽  
Commercial Cultivars ◽  
And Performance ◽  
Putah Creek

Abstract Myoporum spp. (Lamiales: Scrophulariaceae) native to Australia and New Zealand have been introduced into North America and have been widely planted as shrubs and ground covers in the California urban landscape. The invasive thrips, Klambothrips myopori Mound and Morris, invaded California in 2005 and feed exclusively on Myoporum. However, some commercial cultivars have suffered extensive damage, whereas others have not. In field studies and laboratory feeding tests of six different potential host species or cultivars, Myoporum laetum and Myoporum ‘Pacificum’ were identified as most suitable host plants of K. myopori. In laboratory trials, K. myopori failed to complete development on M. ‘Clean n Green’ and M. ‘Putah Creek’. Of the six varieties of Myoporum tested, K. myopori damage was only observed on M. laetum and M. ‘Pacificum’. Although K. myopori can successfully colonize and reproduce on several varieties of Myoporum, they demonstrated a preference for M. laetum and M. ‘Pacificum’ in laboratory and field trials.

scholarly journals Project Sagebrush: Revisiting the Value of the Horizontal Plume Spread Parameter σy

2016 ◽  
Vol 55 (6) ◽  
pp. 1305-1322 ◽  
Author(s):  
D. Finn ◽  
K. L. Clawson ◽  
R. M. Eckman ◽  
H. Liu ◽  
E. S. Russell ◽  
...  
Keyword(s):  
Field Experiments ◽  
National Laboratory ◽  
Field Studies ◽  
Tracer Experiment ◽  
Horizontal Wind ◽  
Plume Dispersion ◽  
Atmospheric Conditions ◽  
Stability Class ◽  
Wind Speeds ◽  
Range Of Values

AbstractThe first phase of an atmospheric tracer experiment program, designated Project Sagebrush, was conducted at the Idaho National Laboratory in October 2013. The purpose was to reevaluate the results of classical field experiments in short-range plume dispersion (e.g., Project Prairie Grass) using the newer technologies that are available for measuring both turbulence levels and tracer concentrations. All releases were conducted during the daytime with atmospheric conditions ranging from neutral to unstable. The key finding was that the values of the horizontal plume spread parameter σy tended to be larger, by up to a factor of ~2, than those measured in many previous field studies. The discrepancies tended to increase with downwind distance. The values of the ratio σy/σθ, where σθ is the standard deviation of the horizontal wind direction, also trend near the upper limit or above the range of values determined in earlier studies. There was also evidence to suggest that the value of σy began to be independent of σθ for σθ greater than 18°. It was also found that the commonly accepted range of values for σθ in different stability conditions might be limiting, at best, and might possibly be unrealistically low, especially at night in low wind speeds. The results raise questions about the commonly accepted magnitudes of σy derived from older studies. These values are used in the parameterization and validation of both older stability-class dispersion models as well as newer models that are based on Taylor’s equation and modern PBL theory.

scholarly journals On the Exchange of Momentum over the Open Ocean

2013 ◽  
Vol 43 (8) ◽  
pp. 1589-1610 ◽  
Author(s):  
James B. Edson ◽  
Venkata Jampana ◽  
Robert A. Weller ◽  
Sebastien P. Bigorre ◽  
Albert J. Plueddemann ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Wind Speed ◽  
Field Experiments ◽  
Field Studies ◽  
Wave Age ◽  
Wind Speeds ◽  
Smooth Flow ◽  
Direct Covariance ◽  
Wave Slope ◽  
Using Data

Abstract This study investigates the exchange of momentum between the atmosphere and ocean using data collected from four oceanic field experiments. Direct covariance estimates of momentum fluxes were collected in all four experiments and wind profiles were collected during three of them. The objective of the investigation is to improve parameterizations of the surface roughness and drag coefficient used to estimate the surface stress from bulk formulas. Specifically, the Coupled Ocean–Atmosphere Response Experiment (COARE) 3.0 bulk flux algorithm is refined to create COARE 3.5. Oversea measurements of dimensionless shear are used to investigate the stability function under stable and convective conditions. The behavior of surface roughness is then investigated over a wider range of wind speeds (up to 25 m s−1) and wave conditions than have been available from previous oversea field studies. The wind speed dependence of the Charnock coefficient α in the COARE algorithm is modified to , where m = 0.017 m−1 s and b = −0.005. When combined with a parameterization for smooth flow, this formulation gives better agreement with the stress estimates from all of the field programs at all winds speeds with significant improvement for wind speeds over 13 m s−1. Wave age– and wave slope–dependent parameterizations of the surface roughness are also investigated, but the COARE 3.5 wind speed–dependent formulation matches the observations well without any wave information. The available data provide a simple reason for why wind speed–, wave age–, and wave slope–dependent formulations give similar results—the inverse wave age varies nearly linearly with wind speed in long-fetch conditions for wind speeds up to 25 m s−1.

Shifting Perspective from Design to Business

2011 ◽  
pp. 130-146
Author(s):  
Andreas Nilsson
Keyword(s):  
Mobile Applications ◽  
Customer Relations ◽  
Field Studies ◽  
Field Trials ◽  
Business Value ◽  
System Evaluation ◽  
Research Project ◽  
Business Relation ◽  
Oriented Research

This chapter investigates potential business value based on the results of a design-oriented research project. The objective of the research was to design mobile applications and services that support spectators in situ at a trotting track. Ethnographic field studies have guided the development of the system TrottingPal. The research has conducted system evaluation through two field trials in the authentic setting with target users. By extending the scope to relate also to other stakeholders in this setting, additional benefits from the TrottingPal system are revealed. This chapter suggests that the designed technology targeted at spectators does not offer only a potential business relation between an event organizer and spectators; rather, it offers new channels for customer relations such as sponsorship and strengthens the locality at the track.

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