A major settlement event associated with minor meteorologic and oceanographic fluctuations

1999 ◽  
Vol 77 (10) ◽  
pp. 1657-1662 ◽  
Author(s):  
Toby Balch ◽  
Bruce G Hatcher ◽  
Robert E Scheibling
Keyword(s):  
Physical Environment ◽  
Atmospheric Pressure ◽  
Low Energy ◽  
Pressure Gradients ◽  
Normal Range ◽  
Sea State ◽  
Velocity Wave ◽  
Rapid Temperature ◽  
Time Of Year ◽  
Settlement Event

Settlement of ophiuroids (Ophiopholis aculeata, Ophiura spp.) was measured using artificial collectors at 3-day intervals during their annual 2-week settlement period in July-August 1993 in St. Margaret's Bay, Nova Scotia. Hydrographic (temperature, salinity, current velocity, wave height and period) and meteorologic conditions (atmospheric pressure and wind velocity) were recorded concurrently at the site or at nearby locations. A major settlement pulse occurred over one 3-day period, with declining settlement over the following 6 days. This pulse was associated with a shift in current direction and preceded by rapid temperature and salinity fluctuations. Similar changes in temperature occurred at a second site (4.5 km away), indicating at least bay-scale forcing. This period was characterised by the passage of weak atmospheric pressure gradients and a low-energy sea state. These meteorologic and oceanographic fluctuations were within the normal range for this time of year, indicating that major settlement events can occur at scales of days in association with minor fluctuations in the physical environment.

Microwave Torch Plasmas for Decomposition of Gaseous Pollutants

2004 ◽  
Vol 7 (1) ◽  
Author(s):  
Mariusz Jasiński ◽  
Jerzy Mizeraczyk ◽  
Zenon Zakrzewski
Keyword(s):  
Atmospheric Pressure ◽  
Energy Cost ◽  
Gas Flow ◽  
Coaxial Line ◽  
Low Energy ◽  
Gaseous Pollutants ◽  
Gas Flow Rate ◽  
Torch Discharge ◽  
Volatile Organic ◽  
Moderate Power

AbstractResults of the study of decomposition of volatile organic compounds (VOCs including Freons) in their mixtures with either synthetic air or nitrogen, and nitrogen oxides NOx in their mixtures with N2 or Ar in low (~ 100 W) and moderate-power (200-400 W) microwave torch plasmas at atmospheric pressure are presented. Three types of microwave torch discharge (MTD) generators, i.e. the low-power coaxial-line-based MID, the moderate-power waveguide-based coaxial-line MTD and the moderate-power waveguide-based MTD generators were used. The gas flow rate and microwave power (2.45 GHz) delivered to the discharge were in the range of 1÷3 l/min and 100÷ 400 W, respectively. Concentrations of the processed gaseous pollutants usually were from several up to several tens percent. The energy efficiency of decomposition of several gaseous pollutants reached 1000 g/kWh. It was found that the microwave torch plasmas fully decomposed the pollutants at relatively low energy cost. This suggests that the MTD plasma can be a useful tool for decomposition of highly-concentrated gaseous pollutants.

scholarly journals Impacts of Atmospheric Pressure on the Annual Maximum of Monthly Sea-Levels in the Northeast Asian Marginal Seas

2020 ◽  
Vol 8 (6) ◽  
pp. 425 ◽  
Author(s):  
MyeongHee Han ◽  
Yang-Ki Cho ◽  
Hyoun-Woo Kang ◽  
SungHyun Nam ◽  
Do-Seong Byun ◽  
...  
Keyword(s):  
Sea Level ◽  
Correlation Coefficient ◽  
Atmospheric Pressure ◽  
Northwest Pacific ◽  
Pressure Gradients ◽  
Northwest Pacific Ocean ◽  
Sea Levels ◽  
Marginal Seas ◽  
Pressure Zone ◽  
Northeast Asian

Monthly mean sea-levels have annual maxima in August in the northeast Asian marginal seas (NEAMS). Based on satellite altimetry data, the rising rate of the August NEAMS sea-level (ANS, 4.2 mm∙yr−1) is greater than those of the NEAMS (3.6 mm∙yr−1) and global (3.4 mm∙yr−1) annual mean sea-levels. Thus, the interannual variations of ANS are classified as relatively high (period H) and low (period L) years and have been analysed because of the high risk of sea-level fluctuation to the coastal regions in August. In period H, there are large atmospheric pressure gradients between the high pressure zone in the Kuroshio Extension (KE) and the low pressure zone in the west of Taiwan (WT). In period L, the atmospheric pressure gradients are small between the above-mentioned zones. Large atmospheric pressure gradients induce strong west-northwestward wind stresses and more Ekman transport from the northwest Pacific Ocean into the NEAMS. The correlation coefficient between August NEAMS sea-level index (ANSI), which is the difference of atmospheric pressure anomalies between the KE and the WT, and the August NEAMS sea-level anomaly (ANSA) is 0.73. Although there is a significant correlation (coefficient: 0.64) between ANSA and the East Asian summer monsoon index (EASMI), ANSI might be more useful in estimating the variability of ANSA.

Development and Commercialization of Large Stationary Engines Utilizing Low BTU Fuel Containing H2/CO

2003 ◽  
Author(s):  
E. Toombs ◽  
T. Stowell ◽  
N. Austin ◽  
P. Danyluk
Keyword(s):  
Carbon Monoxide ◽  
Atmospheric Pressure ◽  
Early Experience ◽  
Low Energy ◽  
Gas Composition ◽  
Pyrolysis Process ◽  
Fuel Gas ◽  
Heating Value ◽  
Cabot Corporation ◽  
Development Cycle

In 1996 Cabot Corporation begun development of engines capable of burning the off-gas from a pyrolysis process used to make carbon black. The fuel gas comes off the process at near atmospheric pressure, high temperature, and saturated with water. After de-watering the gas composition was approximately 16–20% Hydrogen, 16–20% Carbon Monoxide, 1–3% Sulfur compounds and the rest Nitrogen and water. Dewatered heating value of the fuel was around 3350–3720 kJ/nm3. Many engine configurations including both spark and oil ignited were evaluated to utilize this low energy fuel. The paper describes the development cycle and the early experience at commercialization at three sites.

IV—Winds, Currents and Sailing Routes

1977 ◽  
Vol 30 (2) ◽  
pp. 182-184
Author(s):  
Charles H. Cotter
Keyword(s):  
Atmospheric Pressure ◽  
Earth’S Rotation ◽  
Pressure Gradients ◽  
Wind System ◽  
Surface Winds ◽  
Close Attention ◽  
Earth's Rotation ◽  
Surface Temperatures ◽  
Considerable Complexity

The pattern of surface winds on an ideal non-rotating uniform Earth would be related to the distribution of surface temperatures. This would lead to atmospheric pressure gradients which, in turn, would produce surface winds. The effect of the Earth's rotation produces the so-called ‘Planetary Wind System’, and the actual pattern of surface winds is often considered to be a modification of this. But many factors influence the global wind system to such an extent that the explanation of any part of the system at any given time is a matter of considerable complexity. Moreover, experience has amply demonstrated that despite the close attention of physicists the accurate forecasting of winds for more than a day or so ahead has not met with hoped-for success.

Effect of Laser Energy and Atmosphere on the Emission Characteristics of Laser-Induced Plasmas

1993 ◽  
Vol 47 (10) ◽  
pp. 1659-1664 ◽  
Author(s):  
Mikio Kuzuya ◽  
Hitoshi Matsumoto ◽  
Hideaki Takechi ◽  
Osamu Mikami
Keyword(s):  
Energy Range ◽  
Atmospheric Pressure ◽  
Laser Energy ◽  
Low Energy ◽  
Emission Characteristics ◽  
Yag Laser ◽  
Background Ratio ◽  
High Laser ◽  
High Laser Energy ◽  
Temporal And Spatial

The effects of laser energy and atmosphere on the emission characteristics of laser-induced plasmas were studied with the use of a Q-switched Nd: YAG laser over a laser energy range of 20 to 95 mJ. Argon, helium, and air were used as surrounding atmospheres, and the pressures were changed from atmospheric pressure to 1 Torr. The experimental results showed that the maximum spectral intensity was obtained in argon at around 200 Torr at a high laser energy of 95 mJ, whereas the line-to-background ratio was maximized in helium at around 40 Torr at a low energy of 20 mJ. The results are discussed briefly on the basis of the temporal and spatial observations of the laser-induced plasmas.

Geomechanical models and ionospheric variations related to strongest earthquakes and weak influence of atmospheric pressure gradients

2007 ◽  
Vol 414 (1) ◽  
pp. 666-669 ◽  
Author(s):  
V. G. Bondur ◽  
I. A. Garagash ◽  
M. B. Gokhberg ◽  
V. M. Lapshin ◽  
Yu. V. Nechaev ◽  
...  
Keyword(s):  
Atmospheric Pressure ◽  
Pressure Gradients ◽  
Weak Influence

Femtosecond laser filamentation with different atmospheric pressure gradients

Optik ◽  
2016 ◽  
Vol 127 (23) ◽  
pp. 11529-11533 ◽  
Author(s):  
Yuze Hu ◽  
Jinsong Nie ◽  
Qing Ye ◽  
Jintian Bian ◽  
Ke Sun ◽  
...  
Keyword(s):  
Femtosecond Laser ◽  
Atmospheric Pressure ◽  
Pressure Gradients ◽  
Laser Filamentation
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