24,483 research outputs found
Compiled data on the vascular aquatic plant program, 1975 - 1977
The performance of a single cell, facultative sewage lagoon was significantly improved with the introduction of vascular aquatic plants. Water hyacinth (Eichhornia crassipes) was the dominant plant from April to November; duckweed (Lemna spp.) and (Spirodela spp.) flourished from December to March. This 2 ha lagoon received approximately 475 cu m/day of untreated sewage and has a variable COD sub 5 loading rate of 22-30 kg/ha/day. During the first 14 months of operation with aquatic plants, the average influent BOD sub 5 was reduced by 95% from 110 mg/l to an average of 5 mg/l in the effluent. The average influent suspended solids were reduced by 90% from 97 mg/l to 10 mg/l in the effluent. Significant reductions in nitrogen and phosphorus were effected. The monthly kjeldahl nitrogen for influent and effluent averaged 12.0 and 3.4 mg/l, respectively, a reduction of 72%. The total phosphorus was reduced on an average of 56% from 3.7 mg/l influent to 1.6 mg/l effluent
Water hyacinths and alligator weeds for removal of lead and mercury from polluted waters
Removal of lead and mercury by water hyacinths (Eichhornia crassipes) (Mart.) Solms and alligator weeds (Alternanthera philoxeroides) (Mart.) Griesb. was investigated. Water hyacinths demonstrated the ability to remove 0.176 mg of lead and 0.150 mg of mercury per gram of dry plant material from distilled water and river water in a 24-hour period. One acre of water hyacinths is potentially capable of removing 105.6 grams of lead and 90.0 grams of mercury per day. Alligator weeds removed 0.101 mg of lead per gram of dry plant material in a 24-hour period. This same plant also demonstrated the ability to remove a minimum of 0.153 mg of mercury per gram of dry plant material in a six hour period
Nutritional Composition of Water Hyacinths Grown on Domestic Sewage
No abstract availabl
Water Hyacinths for Upgrading Sewage Lagoons to Meet Advanced Wastewater Treatment Standards, Part 1
Water hyacinths, Eichhornia crassipes Mart. Solms, have demonstrated the ability to function as an efficient and inexpensive final filtration system in a secondary domestic sewage lagoon during a three month test period. These plants reduced the suspended solids, biochemical oxygen demanding substances, and other chemical parameters to levels below the standards set by the state pollution control agency. The water hyacinth-covered secondary lagoon utilized in this experiment had a surface area of 0.28 hectare (0.70 acre) with a total capacity of 6.8 million liters (1.5 million gallons), receiving an inflow of 522,100 liters (115,000 gallons) per day from a 1.1 hectare (3.8 acre) aerated primary sewage lagoon. These conditions allowed a retention time of 14 to 21 days depending on the water hyacinth evapotranspiration rates. The desired purity of final sewage effluent can be controlled by the water hyacinth surface area, harvest rate, and the retention time
Energy from aquatic plant wastewater treatment systems
Water hyacinth (Eichhornia crassipes), duckweed (Spirodela sp. and Lemma sp.), water pennywort (Hydrocotyle ranunculoides), and kudzu (Pueraria lobata) were anaerobically fermented using an anaerobic filter technique that reduced the total digestion time from 90 days to an average of 23 days and produced 0.14-0.28 cu m CH4/kg (dry weight) (2.3-4.5 cu ft/lb) from mature filters. The anaerobic filter provided a large surface area for the anaerobic bacteria to establish and maintain an optimum balance of facultative, acid-forming, and methane-producing bacteria. Consequently the efficiency of the process was greatly improved over prior batch fermentations
Water hyacinths and alligator weeds for removal of silver, cobalt, and strontium from polluted waters
Water hyacinths and alligator weeds demonstrated the ability to rapidly remove heavy metals from an aqueous system by root absorption and concentration. Water hyacinths demonstrated the ability to remove 0.439 mg of silver, 0.568 mg of cobalt, and 0.544 mg of strontium in an ionized form per gram of dry plant material in a 24-hour period. Alligator weeds removed a maximum of 0.439 mg of silver, 0.130 mg of cobalt, and 0.161 mg of strontium per gram of dry plant material per day
Perceived Foolishness: How Does the Saltybet Community Construct AI vs AI Spectatorship?
The spectatorship of games has become a topic of growing interest with the parallel rise of esports and livestreaming platforms. Taking Saltybet.com as its primary case study, this paper examines cases where zero-player games played by artificial intelligence-controlled characters are the focus of spectatorship. A discourse analysis identifies trends and themes in the recorded chat transcripts of 15 livestreamed tournaments from Saltybet.com where players bet fake money on the outcome of fighting game matches between AI opponents. Several themes are identified that guide discussion on how spectators discuss AI players as well as their own and the community's behaviour. These insights may be applicable to understanding the broad appeal of the entertainment people derive from AI generally whether they were meant to entertain or not. The discussion explores how the absence of human players and the scale of Saltybet's niche audience contribute to a unique, but foolish space
Revisiting the Cooling Flow Problem in Galaxies, Groups, and Clusters of Galaxies
We present a study of 107 galaxies, groups, and clusters spanning ~3 orders
of magnitude in mass, ~5 orders of magnitude in central galaxy star formation
rate (SFR), ~4 orders of magnitude in the classical cooling rate (dM/dt) of the
intracluster medium (ICM), and ~5 orders of magnitude in the central black hole
accretion rate. For each system in this sample, we measure dM/dt using archival
Chandra X-ray data and acquire the SFR and systematic uncertainty in the SFR by
combining over 330 estimates from dozens of literature sources. With these
data, we estimate the efficiency with which the ICM cools and forms stars,
finding e_cool = SFR/(dM/dt) = 1.4 +/- 0.4% for systems with dM/dt > 30
Msun/yr. For these systems, we measure a slope in the SFR-dM/dt relation
greater than unity, suggesting that the systems with the strongest cool cores
are also cooling more efficiently. We propose that this may be related to, on
average, higher black hole accretion rates in the strongest cool cores, which
could influence the total amount (saturating near the Eddington rate) and
dominant mode (mechanical vs radiative) of feedback. For systems with dM/dt <
30 Msun/yr, we find that the SFR and dM/dt are uncorrelated, and show that this
is consistent with star formation being fueled at a low (but dominant) level by
recycled ISM gas in these systems. We find an intrinsic log-normal scatter in
SFR at fixed dM/dt of 0.52 +/- 0.06 dex, suggesting that cooling is tightly
self-regulated over very long timescales, but can vary dramatically on short
timescales. There is weak evidence that this scatter may be related to the
feedback mechanism, with the scatter being minimized (~0.4 dex) in systems for
which the mechanical feedback power is within a factor of two of the cooling
luminosity.Comment: 16 pages, 10 figures, 6 tables. Submitted to ApJ. Comments welcome
- …