An index to characterize the spatial distribution of land use within watersheds and implications for river network nutrient removal and export

The spatial distribution of land use and associated nutrient inputs may influence the efficacy of in-stream nutrient removal; however, the effect of source location on N removal and watershed N export has not been quantified. We present the skewness index, a metric to quantify the spatial distribution of land use within watersheds. Using this index and a river network nitrogen removal model, we quantified the effect of varying the location of developed land use within two watersheds on nutrient removal and export. The quantity and location of developed land use as well as runoff affected nitrogen removal and export. Because river network nitrogen removal is bypassed when sources are skewed toward the watershed mouth, varying the location of land use alone can double aquatic nitrogen removal. Nutrient sources skewed toward the distant headwaters maximized in-stream removal which in turn can reduce watershed export

Removal of dimethylsulfide, n-hexane and toluene from waste air in a flat membrane bioreactor under continuous conditions

Dimethylsulfide (DMS), n-hexane and toluene removal from a waste air was carried out by using a flat composite membrane bioreactor under continuous feeding conditions. The composite membrane consisted of a dense polydimethylsiloxane top layer with an average thickness of 1.5 μm supported with a porous polyacrylonitrile layer of 50 μm. The membrane bioreactor (MBR) was operated during 9 months in which several operational conditions were applied. The inlet load of each compound ranged from 0 to 350 g m-3 h-1 and removal efficiencies of 80, 70 and 0 to 30 % were reached for DMS, toluene and hexane respectively. Two different empty bed residence time (EBRT) were applied on the MBR in order to check the influence of the residence time on the reactor performance. In this case, DMS and toluene removal increased with an increasing EBRT, while the removal of hexane remained constant. By increasing the flow rate of the recirculated liquid from 22 l min-1 to 45 l min-1, the total performance of the biofilter decreased. To increase the mass transfer of hexane in order to get a higher removal, an emulsion of water/silicone oil 80/20 V% was used as recirculated medium at the liquid side of the reactor. This caused a decrease in DMS removal while the removal of toluene remained constant. The variation on the hexane removal decreased significantly, so the reactor became more reliable for degrading hexane

The removal of thermally aged films of triacylglycerides by surfactant solutions

Thermal ageing of triacylglycerides (TAG) at high temperatures produces films which resist removal using aqueous surfactant solutions. We used a mass loss method to investigate the removal of thermally aged TAG films from hard surfaces using aqueous solutions of surfactants of different charge types. It was found that cationic surfactants are most effective at high pH, whereas anionics are most effective at low pH and a non-ionic surfactant is most effective at intermediate pH. We showed that the TAG film removal process occurs in several stages. In the first ‘‘lag phase’’ no TAG removal occurs; the surfactant first partitions into the thermally aged film. In the second stage, the TAG film containing surfactant was removed by solubilisation into micelles in the aqueous solution. The effects of pH and surfactant charge on the TAG removal process correlate with the effects of these variables on the extent of surfactant partitioning to the TAG film and on the maximum extent of TAG solubilisation within the micelles. Additionally, we showed how the TAG removal is enhanced by the addition of amphiphilic additives such as alcohols which act as co-surfactants. The study demonstrates that aqueous surfactant solutions provide a viable and more benign alternative to current methods for the removal of thermally aged TAG films

1993 Juvenile Justice and Delinquency Prevention Act Compliance Monitoring Report

The Juvenile Justice and Delinquency Prevention Act (JJDPA) mandates removal of status offenders and nonoffenders from secure detention and correctional facilities, sight and sound separation of juveniles and adults, and removal of juveniles from adult jails and lockups. In Alaska, no instances of a status offender held in secure detention was recorded in 1993, as compared with 485 violations in the baseline year of 1976. 16 separation violations were recorded in 1992, representing a 98% reduction from the 1976 baseline of 824 violations. 59 jail removal violations were projected, representing a 94% reduction from the 1980 baseline and an 25% increase from 1992.Alaska Department of Health and Social Services, Division of Family and Youth ServicesA. General Information / B. Removal of Status Offenders and Nonoffenders from Secure Detention and Correctional Facilities / C. De Minimis Request / D. Progress Made in Achieving Removal of Status Offenders and Nonoffenders from Secure Detention and Correctional Facilities / E. Separation of Juveniles and Adults / F. Removal of Juveniles from Adult Jails and Lockups / G. De Minimis Request: Numerical / H. De Minimis Request: Substantive / APPENDICES / I. Method of Analysis / II. 1993 Violations by Offense Type and Location / III. Common Offense Acronym

Film breakers prevent migration of aqueous potassium hydroxide in fuel cells

Electrolyte film breakers made from polytetrafluoroethylene are installed in the reactant and water vapor removal outlets of each cell and sealed by elastomers. Use of these devices in the water vapor removal cavity outlets prevents loss of KOH solution through film migration during water removal

FY 1996 Juvenile Justice and Delinquency Prevention Act Compliance Monitoring Report

The Juvenile Justice and Delinquency Prevention Act (JJDPA) mandates removal of status offenders and nonoffenders from secure detention and correctional facilities, sight and sound separation of juveniles and adults, and removal of juveniles from adult jails and lockups. In Alaska, 4 instances of a status offender held in secure detention were recorded in FY 1996, compared with 485 violations in the baseline year of CY 1976. 3 separation violations were recorded in FY 1997, representing a 99.6% reduction from the CY 1976 baseline of 824 violations. 44 jail removal violations were projected, representing an 95% reduction from the CY 1980 baseline.Alaska Department of Health and Social Services, Division of Family and Youth ServicesA. General Information / B. Removal of Status Offenders and Nonoffenders from Secure Detention and Correctional Facilities / C. De Minimis Request / D. Progress Made in Achieving Removal of Status Offenders and Nonoffenders from Secure Detention and Correctional Facilities / E. Separation of Juveniles and Adults / F. Removal of Juveniles from Adult Jails and Lockups / G. De Minimis Request: Substantive / APPENDICES / I. Method of Analysis / II. FY96 Violations by Offense Type and Location / III. Common Offense Acronym

Treatability of U.S. Environmental Protection Agency Contaminant Candidate List Viruses: Removal of Coxsackievirus and Echovirus using Enhanced Coagulation

Enhanced coagulation was evaluated for removal efficacy of coxsackievirus and echovirus (Contaminant Candidate List [CCL] enteroviruses), poliovirus, four potential surrogate bacteriophages, and dissolved organic carbon (DOC). Viruses and DOC were effectively removed using enhanced coagulation, with removals generally improving as dose increased and pH decreased. Optimal enhanced coagulation conditions of 40 mg/L FeCl3 and pH between 5 and 6.5 resulted in a maximum removal of 3.0 logs of coxsackievirus B6, 1.75 logs of echovirus 12, 2.5 logs of poliovirus 1, 1.8 logs of fr, 1.3 logs of phi-X174, 0.36 logs of MS2, 0.29 logs of PRD1, and 41% DOC. Bacteriophages fr and phi-X174 appear to be the most representative surrogates for the physical removal of coxsackievirus, while MS2 and PRD1 are more conservative. For echovirus, MS2 and PRD1 appear to be the most appropriate surrogates. The relative removal profiles of the enteroviruses (greatest removal of coxsackievirus followed by poliovirus and then echovirus) suggest that studies of the physical removal of poliovirus may be extended to the CCL enteroviruses. These results contribute to evaluations of the CCL and regulatory status of coxsackievirus and echovirus and aid in building a database of the treatment efficiencies of enteroviruses and their surrogates

General removal lemma

We formulate and prove a general result in spirit of hypergraph removal lemma for measurable functions of several variables.Comment: 5 page