Plastic encapsulated semiconductors; field performance vs. laboratory testing

1972 ◽  
Vol 11 (1) ◽  
pp. 14
2021 ◽  
Author(s):  
Lianghao Chen

Soil Cell is a novel Low-Impact Development practice that is suitable for densely developed urban environment. This thesis seeks to gain further understanding of soil cell’s performance in terms of water quality and quality control; and to assess the exfiltration performance of perforated pipe in soil cells by monitoring an active cell. The monitoring result showed that the cell was very effective in treating particulate (90% concentration reduction), metal (91% lead concentration reduction to 53% copper concentration reduction) and phosphorus (74% concentration reduction). The cell was ineffective in treating chloride (1% concentration increase, no statistical significance) and even caused nitrate leaching (65% concentration increase). Field performance of the soil cell indicated that the inflow perforated backed up frequently, restricting the flow into the cell but laboratory testing of the perforated pipes’ hydraulic performance confirms that the pipe has a sufficient capacity to convey the flows of up to 10 L/s.


1969 ◽  
Vol 101 (2) ◽  
pp. 159-163 ◽  
Author(s):  
K. S. McKinlay

AbstractFourteen insecticides were tested by direct contact against second-instar nymphs of a grasshopper, Melanoplus sanguinipes F. Of these, seven were judged to be sufficiently promising to be compared for toxicity and persistence as deposits on wheat seedlings. Comparison with a dieldrin standard showed that Dursban, Dibrom, and malathion were extremely effective by contact but had little persistence on growing wheat. Baygon was extremely effective by contact and showed some persistence. CIBA 9643 and dimethoate were the only two compounds to show persistent effects almost equivalent to dieldrin, and CIBA 9643 was more toxic than dieldrin by direct contact.It was concluded that CIBA 9643 was the only compound, of those tested, which might give grasshopper control equivalent to, or better than, dieldrin or the currently recommended dimethoate.


Author(s):  
Nader Amer ◽  
Norbert Delatte ◽  
Chris Storey

Roller-compacted concrete (RCC) is a durable, economical, low-maintenance material for low-speed, heavy-duty paving applications, including industrial and multimodal pavements. However, it is difficult to prepare laboratory specimens to represent field performance, because RCC is very dry and requires considerable compactive effort to achieve field densities. The gyratory compactor, commonly used to prepare hot-mix asphalt specimens, may be used in preparing specimens for laboratory testing. Materials and mix designs from two industrial paving projects were used to prepare specimens for comparison. Field results indicated that the gyratory compactor produced specimens with mechanical properties consistent with those achieved in the field. Specimens had high strength and consistent density, with low variability. The gyratory compactor may be used to replace other methods presently used for preparing RCC specimens such as the modified Vebe apparatus, the vibrating table, and the vibrating hammer. These methods have limitations that may be overcome with the gyratory compactor because of its consistency and its compatibility with field results. The effects of density and specimen aspect ratio on compressive and splitting tensile strength were investigated. The number of gyrations applied to the specimen may be used to duplicate the desired field density. For the industrial pavements investigated, approximately 60 gyrations accurately replicated field conditions.


Author(s):  
Navneet Garg ◽  
Marshall R. Thompson

Pavement rehabilitation and reconstruction operations have generated large supplies of reclaimed asphalt concrete (RAC). In Illinois crushed RAC generally called recycled asphalt pavement (RAP) supplies are not 100 percent recycled into hot-mix asphalt concrete production. RAP acceptance as a pavement base material has been limited because of the lack of laboratory testing information, information on structural behavior, and field performance data. Limited preliminary laboratory testing and isolated commercial and local road agency paving experience in Illinois indicate that RAP has significant potential as a pavement base. RAP base potential was evaluated by constructing the Lincoln Avenue (Urbana, Illinois) demonstration project during late September and early October 1993. The pavement section is a 305-mm (12-in.) lime-modified, fine-grained subgrade, a 203-mm (8-in.) compacted RAP base, and a 76-mm (3-in.) dense-graded asphalt concrete surface course. The construction, structural response, and performance of the Lincoln Avenue RAP base project were monitored as part of a cooperative study (Illinois Department of Transportation, City of Urbana, and University of Illinois). The accumulated construction, field testing and evaluation, and laboratory testing data and information are summarized. The field construction experience, field control test data, laboratory testing results, falling weight deflectometer results, and Lincoln Avenue performance data indicate that RAP can successfully be used as a conventional flexible pavement base material. The performance of the Lincoln Avenue RAP base pavement (to date) is comparable with that of a crushed stone base.


2021 ◽  
Author(s):  
Lianghao Chen

Soil Cell is a novel Low-Impact Development practice that is suitable for densely developed urban environment. This thesis seeks to gain further understanding of soil cell’s performance in terms of water quality and quality control; and to assess the exfiltration performance of perforated pipe in soil cells by monitoring an active cell. The monitoring result showed that the cell was very effective in treating particulate (90% concentration reduction), metal (91% lead concentration reduction to 53% copper concentration reduction) and phosphorus (74% concentration reduction). The cell was ineffective in treating chloride (1% concentration increase, no statistical significance) and even caused nitrate leaching (65% concentration increase). Field performance of the soil cell indicated that the inflow perforated backed up frequently, restricting the flow into the cell but laboratory testing of the perforated pipes’ hydraulic performance confirms that the pipe has a sufficient capacity to convey the flows of up to 10 L/s.


2001 ◽  
Vol 298 (1-2) ◽  
pp. 95-111 ◽  
Author(s):  
B.P. McGrail ◽  
D.H. Bacon ◽  
J.P. Icenhower ◽  
F.M. Mann ◽  
R.J. Puigh ◽  
...  

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