The biodegradation of organic chemical waste using a constructed horizontal reedbed treatment system

The aim of the project was to evaluate the potential for a constructed reedbed (planted with Phragmites australis) to aid in the biodegradation of triethylene glycol (TEG) under normal climatic conditions experienced at the site. The approach taken was to design and construct a series of test beds which could be used in replicated experiments to measure the rate at which TEG solutions of different concentrations were degraded. The effect of the TEG on reeds and the interactions between TEG and physical conditions within the test beds were monitored and in addition, the potential use of two methods which might be used instead of the BOD(_5) method were assessed.Although the temperature range experienced during the series ranged from 2.5 C to18.5 C, TEG was degraded within four days at both high and low temperatures. Theinitial decline in TEG concentrations was rapid and this was thought to be partly due tosome dilution by water but mainly by the action of bacteria within the reedbed.Subsequently, TEG concentration declined more slowly. The TEG concentrations used inthe tests were between 0.1 %v/v and 5.0%v/v with the higher concentrations degradingfaster initially, but the overall degradation rates being similar. The physical conditionswithin the treatment tanks compared to the controls showed that temperature was notaffected, pH was unaffected in the early trials but showed slight changes to aciditytowards the final trials. Conductivity in both control and treatment beds showed similarunexplainable variances until the later treatments when the treatment beds displayed higher values than those found in the control beds. Dissolved oxygen in the treatment beds was lower than in the untreated beds as was expected due to bacterial action. The effect of dosing with TEG on the reeds was to increase the number of shoots per area and Total Kjeldhal Nitrogen (TKN) content after one season with biomass production of the treated beds increasing after two years. The stomatal count on second year plants showed a significant increase in the treated reeds against the untreated ones. A brief investigation of the impact of TEG on micro-organisms within the test beds indicated that some species of bacteria were probably 'tegophilic' i.e. bacteria that flourish in a medium containing TEG and that сіliate protozoa were not adversely affected. Of the two methods examined to replace the BOD(_5) test, the EZBOD® meter was found unsuitable due, it was thought, to the bactericidal properties of the TEG. Trials using a Total Organic Carbon analyser indicated that this rapid method would be a successful supplement and/or replacement to the BOD(_5) method currently used to monitor whether waste water quality meets disposal requirements imposed by the Environment Agency. It was found that the TEG did biodegrade without having any adverse effects on the reeds and that the degradation was a first order reaction. A reaction rate was determined that will enable anybody to determine the requirements of a treatment system to deal with effluent containing TEG

The effect of chine tires on nose gear water-spray characteristics of a twin engine airplane

An experimental investigation was performed to evaluate the effectiveness of nose gear chine tires in eliminating or minimizing the engine spray ingestion problem encountered on several occasions by the Merlin 4, a twin-engine propjet airplane. A study of the photographic and television coverage indicated that under similar test conditions the spray from the chine tires presented less of a potential engine spray ingestion problem than the conventional tires. Neither tire configuration appeared to pose any ingestion problem at aircraft speeds in excess of the hydroplaning speed for each tire, however, significant differences were noted in the spray patterns of the two sets of tires at sub-hydroplaning speeds. At sub-hydroplaning speeds, the conventional tires produced substantial spray above the wing which approached the general area of the engine air inlet at lower test speeds. The chine tires produced two distinct spray plumes at sub-hydroplaning speeds: one low-level plume which presented no apparent threat of ingestion, and one which at most test speeds was observed to be below the wing leading edge and thus displaced from the intakes on the engine nacelle

Combinatorial biomaterials discovery strategy to identify new macromolecular cryoprotectants

Cryoprotective agents (CPAs) are typically solvents or small molecules, but there is a need for innovative CPAs to reduce toxicity and increase cell yield, for the banking and transport of cells. Here we use a photochemical high-throughput discovery platform to identify macromolecular cryoprotectants, as rational design approaches are currently limited by the lack of structure–property relationships. Using liquid handling systems, 120 unique polyampholytes were synthesized using photopolymerization with RAFT agents. Cryopreservation screening identified “hit” polymers and nonlinear trends between composition and function, highlighting the requirement for screening, with polymer aggregation being a key factor. The most active polymers reduced the volume of dimethyl sulfoxide (DMSO) required to cryopreserve a nucleated cell line, demonstrating the potential of this approach to identify materials for cell storage and transport

Targeting in Outer Space: An Exploration of Regime Interactions in the Final Frontier

Space infrastructure is now integral to both civilian life and warfare. Belligerents may find great military advantage in destroying a satellite in orbit, but this could have grave consequences for civilians on earth and create long-lasting space debris. This Article identifies the applicable law by harmonizing international humanitarian law, human rights law, and international space law. The Authors conclude that targeting a satellite in armed conflict will be permissible only as a measure of last resort, not of first response

A comparison between ion characteristics observed by the POLAR and DMSP spacecraft in the high-latitude magnetosphere

We study here the injection and transport of ions in the convection-dominated region of the Earth’s magnetosphere. The total ion counts from the CAMMICE MICS instrument aboard the POLAR spacecraft are used to generate occurrence probability distributions of magnetospheric ion populations. MICS ion spectra are characterised by both the peak in the differential energy flux, and the average energy of ions striking the detector. The former permits a comparison with the Stubbs et al. (2001) survey of He2+ ions of solar wind origin within the magnetosphere. The latter can address the occurrences of various classifications of precipitating particle fluxes observed in the topside ionosphere by DMSP satellites (Newell and Meng, 1992). The peak energy occurrences are consistent with our earlier work, including the dawn-dusk asymmetry with enhanced occurrences on the dawn flank at low energies, switching to the dusk flank at higher energies. The differences in the ion energies observed in these two studies can be explained by drift orbit effects and acceleration processes at the magnetopause, and in the tail current sheet. Near noon at average ion energies of _1 keV, the cusp and open LLBL occur further poleward here than in the Newell and Meng survey, probably due to convectionrelated time-of-flight effects. An important new result is that the pre-noon bias previously observed in the LLBL is most likely due to the component of this population on closed field lines, formed largely by low energy ions drifting earthward from the tail. There is no evidence here of mass and momentum transfer from the solar wind to the LLBL by nonreconnection coupling. At higher energies (_2–20 keV), we observe ions mapping to the auroral oval and can distinguish between the boundary and central plasma sheets. We show that ions at these energies relate to a transition from dawnward to duskward dominated flow, this is evidence of how ion drift orbits in the tail influence the location and behaviour of the plasma populations in the magnetosphere

Charging and Subsequent Dissipation of a Rover Wheel in the Lunar Polar Regions

As a roving vehicle moves along the lunar surface, electric charge will build up through tribo-charging. This charge collected by the roving object will have a dissipative path to either the surface or the ambient plasma, depending upon which path is most conductive. At the lunar terminator region and into nightside regions, the surface is very cold and becomes a very poor conductor. leaving the plasma as the dominant remediating current for dissipation. However, within lunar craters, even plasma currents become substantially reduced which then greatly increases electric 'dissipation times, This work will involve the advancement of the stepping astronaut charge model, by considering the charging and plasma dissipation of a rolling rover wheel, The objective of this work is to determine the nature of charging and discharging for a rover wheel as it rolls along the cold, plasma-starved lunar polar regions. The rotating wheel accumulates charge via contact electrification (tribo-charging) with the lunar regolith. This tribo-charging is dependent on the composition of the objects in contact, with insulators and conductors charging differently. Given the environmental plasma in the region, we then determine the dissipation time for the wheel to bleed off its excess charge into the surrounding plasma. A model of the rover wheel rotating continuously over a surface regolith within a polar crater has been applied. The environmental plasma has been described previously. We define a new tribo-charging term specifically for the rotating system, with charge levels defined as a function of the wheel size, area in contact with the regolith, regolith particle size distribution, as well as the velocity at which the wheel is turning. We recognize that as charged dust accumulates and sticks to the wheel, this behaves effectively as a new current. Hence, the overall charging of the system should no longer vary linearly. and begin to show signs of saturation, We are devising a dust current term to model this charge-limiting effect, and will present the results in discussion

Testing of the LSST's photometric calibration strategy at the CTIO 0.9 meter telescope

The calibration hardware system of the Large Synoptic Survey Telescope (LSST) is designed to measure two quantities: a telescope's instrumental response and atmospheric transmission, both as a function of wavelength. First of all, a "collimated beam projector" is designed to measure the instrumental response function by projecting monochromatic light through a mask and a collimating optic onto the telescope. During the measurement, the light level is monitored with a NIST-traceable photodiode. This method does not suffer from stray light effects or the reflections (known as ghosting) present when using a flat-field screen illumination, which has a systematic source of uncertainty from uncontrolled reflections. It allows for an independent measurement of the throughput of the telescope's optical train as well as each filter's transmission as a function of position on the primary mirror. Second, CALSPEC stars can be used as calibrated light sources to illuminate the atmosphere and measure its transmission. To measure the atmosphere's transfer function, we use the telescope's imager with a Ronchi grating in place of a filter to configure it as a low resolution slitless spectrograph. In this paper, we describe this calibration strategy, focusing on results from a prototype system at the Cerro Tololo Inter-American Observatory (CTIO) 0.9 meter telescope. We compare the instrumental throughput measurements to nominal values measured using a laboratory spectrophotometer, and we describe measurements of the atmosphere made via CALSPEC standard stars during the same run