Geomechanics Study In Sabak Field - Investigation Of Casing Restriction And Deformation In Shallow Sand Formation

2013 ◽  
Author(s):  
Aprianto Sitio ◽  
Raihan Raihan ◽  
Marius Tjengdrawira ◽  
Annur Suhadi ◽  
Romi Sagita ◽  
...  
Keyword(s):  
Field Investigation

Weekly Exercise Consistently Reinstates Positive Mood

1998 ◽  
Vol 3 (4) ◽  
pp. 271-280 ◽  
Author(s):  
Hannah Steinberg ◽  
Briony R. Nicholls ◽  
Elizabeth A. Sykes ◽  
N. LeBoutillier ◽  
Nerina Ramlakhan ◽  
...  
Keyword(s):  
Physical Exercise ◽  
Negative Mood ◽  
Real Life ◽  
Positive Mood ◽  
Field Investigation ◽  
Single Bout ◽  
Before And After ◽  
Exercise Class ◽  
Negative Feelings ◽  
Over Time

Mood improvement immediately after a single bout of exercise is well documented, but less is known about successive and longer term effects. In a “real-life” field investigation, four kinds of exercise class (Beginners, Advanced, Body Funk and Callanetics) met once a week for up to 7 weeks. Before and after each class the members assessed how they felt by completing a questionnaire listing equal numbers of “positive” and “negative” mood words. Subjects who had attended at least five times were included in the analysis, which led to groups consisting of 18, 20, 16, and 16 subjects, respectively. All four kinds of exercise significantly increased positive and decreased negative feelings, and this result was surprisingly consistent in successive weeks. However, exercise seemed to have a much greater effect on positive than on negative moods. The favorable moods induced by each class seemed to have worn off by the following week, to be reinstated by the class itself. In the Callanetics class, positive mood also improved significantly over time. The Callanetics class involved “slower,” more demanding exercises, not always done to music. The Callanetics and Advanced classes also showed significantly greater preexercise negative moods in the first three sessions. However, these differences disappeared following exercise. Possibly, these two groups had become more “tolerant” to the mood-enhancing effects of physical exercise; this may be in part have been due to “exercise addiction.”

Production of asari (Manila) clams, Ruditapes philippinarum, during the period of harvest decrease in the 2000s in the Banzu tidal area, Tokyo Bay

2020 ◽  
Vol 33 ◽  
pp. 14
Author(s):  
Mitsuharu Toba ◽  
Jun Kakino ◽  
Kazuo Tada ◽  
Yutaka Kobayashi ◽  
Hideharu Tsuchie
Keyword(s):  
Field Investigation ◽  
Ruditapes Philippinarum ◽  
Management Style ◽  
Seed Stock ◽  
Tokyo Bay ◽  
Yearly Variation ◽  
Culture Area ◽  
Stock Biomass ◽  
Tidal Area ◽  
High Level

In Tokyo Bay, the harvestable quantity of asari (Manila) clams Ruditapes philippinarum has been decreasing since the late 1990s. We conducted a field investigation on clam density in the Banzu culture area from April 1988 to December 2014 and collected records spanning January 1986 to September 2017 from relevant fisheries cooperative associations to clarify the relationship between the temporal variation in stock abundance and the production activities of fishermen. The yearly variation in clam abundance over the study period was marked by larger decreases in the numbers of larger clams. A large quantity of juvenile clams, beyond the biological productivity of the culture area, may have been introduced as seed stock in the late 1980s despite the high level of harvestable stock. The declines in harvested quantity began in the late 1990s and may have been caused by decreases in harvestable stock despite the continuous addition of seed stock clams. The harvested quantity is likely to be significantly dependent upon the wild clam population, even within the culture area, as the harvestable quantity was not correlated with the quantity of seed stock introduced during the study period. These declines in harvested quantity may have resulted from a decreasing number of operating harvesters due to the low level of harvestable stock and consequently reduced profitability. Two findings were emphasized. A certain management style, based on predictions of the contributions of wild and introduced clams to future stock biomass, is essential for economically-feasible culturing. In areas with less harvestable stock, actions should be taken to maintain the incomes of harvesters while avoiding overexploitation, even if the total harvest quantity decreases.

Influence of Flexible Side-Chains on the Breathing Phase Transition of Pillared Layer MOFs: A Force Field Investigation

2020 ◽  
Author(s):  
Julian Keupp ◽  
Johannes P. Dürholt ◽  
Rochus Schmid
Keyword(s):  
First Principles ◽  
Good Accuracy ◽  
Field Investigation ◽  
Square Lattice ◽  
Side Chain ◽  
Second Step ◽  
Side Chains ◽  
Dynamics Simulations ◽  
Complex Phenomena ◽  
Closed Pore

The prototypical pillared layer MOFs, formed by a square lattice of paddle-<br>wheel units and connected by dinitrogen pillars, can undergo a breathing phase<br>transition by a “wine-rack” type motion of the square lattice. We studied this not<br>yet fully understood behavior using an accurate first principles parameterized force<br>field (MOF-FF) for larger nanocrystallites on the example of Zn 2 (bdc) 2 (dabco) [bdc:<br>benzenedicarboxylate, dabco: (1,4-diazabicyclo[2.2.2]octane)] and found clear indi-<br>cations for an interface between a closed and an open pore phase traveling through<br>the system during the phase transformation [Adv. Theory Simul. 2019, 2, 11]. In<br>conventional simulations in small supercells this mechanism is prevented by periodic<br>boundary conditions (PBC), enforcing a synchronous transformation of the entire<br>crystal. Here, we extend this investigation to pillared layer MOFs with flexible<br>side-chains, attached to the linker. Such functionalized (fu-)MOFs are experimen-<br>tally known to have different properties with the side-chains acting as fixed guest<br>molecules. First, in order to extend the parameterization for such flexible groups,<br>1a new parametrization strategy for MOF-FF had to be developed, using a multi-<br>structure force based fit method. The resulting parametrization for a library of<br>fu-MOFs is then validated with respect to a set of reference systems and shows very<br>good accuracy. In the second step, a series of fu-MOFs with increasing side-chain<br>length is studied with respect to the influence of the side-chains on the breathing<br>behavior. For small supercells in PBC a systematic trend of the closed pore volume<br>with the chain length is observed. However, for a nanocrystallite model a distinct<br>interface between a closed and an open pore phase is visible only for the short chain<br>length, whereas for longer chains the interface broadens and a nearly concerted trans-<br>formation is observed. Only by molecular dynamics simulations using accurate force<br>fields such complex phenomena can be studied on a molecular level.

Behaviour of Coli Phages in Oxidation Ponds

1985 ◽  
Vol 17 (10) ◽  
pp. 219-227 ◽  
Author(s):  
T. Omura ◽  
H. K. Shin ◽  
A. Ketratanakul
Keyword(s):  
Laboratory Experiments ◽  
Field Investigation ◽  
Host Cells ◽  
Coliform Bacteria ◽  
Alkaline Ph ◽  
Viral Inactivation ◽  
Effects Of Temperature ◽  
Oxidation Ponds ◽  
Incubation Temperatures ◽  
Inactivation Efficiency

Coliphages are among the most promising indicators of viral inactivation efficiency of wastewater treatment. Therefore, it is important to investigate the behaviour of coliphages in oxidation ponds from the viewpoint of predicting the inactivation of infectious viruses. In this study, numbers of coliphages were measured in oxidation ponds consisting of a series of facultative and maturation ponds. In parallel with this investigation, the effects of temperature and pH on the behaviour of coliphages were examined in the laboratory, employing three species of coliform bacteria as host cells. The field investigation showed that there was positive correlation between counts of coliphages and those of coliform bacteria, and that more than 99% of coliphages were inactivated. The inactivation efficiency of coliphages in the facultative pond was much higher than in the maturation pond. The results of the laboratory experiments indicated that at 30°C more than 99% of the coliform group were destroyed in 7 days of incubation and that coliphages counts increased from 105/100 ml to 107/100 ml with a lag time of 3 days. Greater reduction of the coliform count was obtained at higher incubation temperatures. It was observed that the coliphages possessed greater ability to attack coliform bacteria at acidic rather than alkaline pH.

The Characteristics of Community Wastewater Biological Treatment Processes in Taiwan

1986 ◽  
Vol 18 (7-8) ◽  
pp. 289-296
Author(s):  
C. F. Ouyang ◽  
T. J. Wan
Keyword(s):  
Biological Treatment ◽  
Wastewater Treatment Plants ◽  
Oxygen Demand ◽  
Field Investigation ◽  
Oxidation Ditch ◽  
Trickling Filter ◽  
Rotating Biological Contactor ◽  
Treatment Processes ◽  
Treatment Characteristics ◽  
Sludge Thickening

This study investigated and compared the treatment characteristics of three different kinds of biological wastewater treatment plants (including rotating biological contactor, trickling filter and oxidation ditch) which are currently operated in Taiwan. The field investigation of this study concentrated on the following items: the performance of biological oxygen demand (BOD) and suspended solids (SS) removal; the sludge yield rate of BOD removal; the settleability of sludge solids; the properties of sludge thickening; the power consumption and land area requirement per unit volume of wastewater. Finally, based on the results of the field investigation, a comparison of the treatment characteristics of the three different biological treatment processes was evaluated.

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