Assessing Biofiltration without Ozonation for Removal of Trihalomethane Precursors in Drinking Water at the Beaver Water District Drinking Water Treatment Plant

Biofiltration without pre-ozonation has the capability to remove natural organic matter (NOM) fractions that serve as precursors of disinfection byproducts (DBPs), which include the four regulated trihalomethanes (THMs) and dichloroacetonitrile (DCAN). Rapid small-scale column tests (RSSCTs) and Pilot Plant filters operated at empty-bed contact times (EBCTs) of 4, 8, and 16 minutes were used to evaluate the performance of nutrient-amended (free ammonia and phosphorus) biofiltration for THM and DCAN precursor removal, as measured using formation potential (FP) tests. NOM surrogates – which include dissolved organic carbon (DOC), specific ultraviolet absorbance (SUVA254) and fluorescence-PARAFAC components – were measured weekly throughout the 30-week study to assess their suitability to track DBP precursor removal. RSSCTs containing DOC-exhausted granular activated carbon (GAC) removed up to 25% of the DOC with removal increasing (=0.01) with EBCT between 4 and 16 mins. During the 11-week period of active nitrification in the RSSCTs, average removals of total THMFP and DCANFP were 21% and 44%, respectively. However, statistically similar removals (=0.01) were observed at 8 and 16 mins EBCT, indicating that EBCTs in excess of 8 mins would not be helpful unless additional pretreatment steps such as pre-ozonation or a higher chlorine dioxide dose were added prior to the biofilters to increase the amount of biodegradable NOM. Relative to the RSSCTs, the Pilot filters achieved higher average removals of DOC, SUVA254, TTHMFP and DCANFP because their GAC media was not exhausted with respect to DOC and thus NOM was sorbed by physical-chemical mechanisms. Weak linear correlations observed between NOM surrogates and TTHMFP (R2 \u3c 0.27) during the active nitrification period in the RSSCTs indicate that these surrogates are not useful for monitoring THM precursor removal in nutrient-enhanced biofilters and therefore DBPFP tests are required to assess biofiltration performance

Network Structure and Design in the Deregulated U.S. Airline Industry: an Argument for Re-Regulation?

This paper develops a model to explain and analyze the evolution of network structure (connectivity)and design (flight frequency, aircraft size, prices) in the post-deregulation U.S. airline industry. We show that legacy carriers choice of Hub-and-Spoke networks and the emergence of low cost carriers (LCCs) operating Point-to-Point networks were optimal choices. We demonstrate that LCCs need not necessarily charge lower prices, and their entry impacted legacy carriers’ prices in all markets, even those where there is no direct competition. We show that in response to entry, legacy carriers optimally lower flight frequency, leading to longer wait times between flights for which passengers are compensated by lower prices; conversely, if the entrant later exits, legacy carriers raise flight frequency and therefore prices, which may erroneously appear to be predatory pricing when in fact it is the consequence of optimal network redesign. Finally, we demonstrate that even though low cost carriers lower prices, total social welfare with competing network structures can also be lowered. In other words, the poor financial performance of legacy carriers is not due to their inefficiency per se but due to an efficient Hub-and-Spoke network undermined by competition from inefficient Point-to-Point networks. We argue that social welfare may have been, and still can be, higher if entry and exit in air passenger travel industry is regulated.Networks, Airlines, Regulation

Quality assurance for the ALICE Monte Carlo procedure

We implement the already existing macro,$ALICE_ROOT/STEER /CheckESD.C that is ran after reconstruction to compute the physics efficiency, as a task that will run on proof framework like CAF. The task was implemented in a C++ class called AliAnalysisTaskCheckESD and it inherits from AliAnalysisTaskSE base class. The function of AliAnalysisTaskCheckESD is to compute the ratio of the number of reconstructed particles to the number of particle generated by the Monte Carlo generator.The class AliAnalysisTaskCheckESD was successfully implemented. It was used during the production for first physics and permitted to discover several problems (missing track in the MUON arm reconstruction, low efficiency in the PHOS detector etc.). The code is committed to the SVN repository and will become standard tool for quality assurance.Comment: 7 pages, 7 figure

High energy routes to reactive intermediates: Computational and experimental studies

We developed microwave flash pyrolysis (MFP), using graphite and other sensitizers to carry out high temperature reactions. Newly developed is a closed vessel MFP method. Studies to date include isomerization of azulene to naphthalene, generation of benzyne, cycloaromatizations, and rearrangements. New thermal sensitizers included silicon carbide, titanium dioxide and diverse metal oxides. Graphite remains the most effective thermal sensitizer. Sealed tube MFP was utilized to investigate the Brown rearrangement of aryl alkynes. CCSD(T)//M05-2X computations have been carried out for both concerted and stepwise mechanisms in dehydro-Diels-Alder reactions of ethene and ethyne with vinylacetylene and 1,3-butadiyne. Concerted transition states for enyne-ene and enyne-yne reactions are ca. 6--7 kcal/mol lower in energy than the stepwise transition states. Diyne-ene and diyne-yne reactions can proceed through a concerted mechanism to give 1,2,3-cyclohexatriene or ortho -benzyne; however the computed energy differences between the concerted and the stepwise transition states are \u3c 2 kcal/mol

Energy Smart Buildings: Potential for Conservation and Efficiency of Energy

Energy is the basic ingredient for economic growth and development [Lorde, et al. (2010)]. Presently demand for energy has significantly increased due to the overall expansion of economic and industrial activity in all important economic sectors e.g. industry, agriculture, and services. In addition to the expansion of economic activity and subsequent increase in energy demand at industrial level, population growth and increased consumption are also adding to the demand for energy [OECD (2011)]. In other words, modern economy has become highly dependent on energy resources. In order to meet the increased energy demand and ensure its sustainable supply, there is a need to have strong and robust plans with all options to consider at various levels

Modelling farmer and consumer preferences for cleaner food production

Agriculture in Pakistan is currently unsustainable due to intensive farming practices – the concentrated use of agricultural inputs, including water and agrochemicals. The widespread use of intensive farming has dire effects on both human health and the natural environment. As such the antidote to these problems would be the adoption of sustainable agriculture. The present research proposes to reduce the use of agrochemicals such as pesticides and fertilisers, and adopt efficient irrigation technology in tomato cultivation in district Khushab Pakistan. Discrete choice experiment (DCE) approach is deployed to study farmer and consumer preferences and their valuation of the proposed changes to facilitate the adoption of sustainable agriculture in tomato cultivation. Questionnaire data is used to investigate farmer and consumer perceptions and understanding of existing farming practices and proposed changes. Findings reveal that majority farmers and consumers are aware of the unfavourable health and environmental impacts of existing farming practices used in tomato cultivation. Empirical analysis of questionnaire data show that farmers who own their farmland and those who have received the training to apply agrochemicals are more likely to have a positive perception of the proposed changes. Likewise, consumers who have more awareness and information about different farming practices and a greater health consciousness are more keen to see the changes in existing farming practices. DCE analysis shows that farmers prefer the reduction in the use of pesticide and fertiliser use, but place a negative value on the adoption of drip irrigation. On the other hand, consumers not only prefer the proposed changes, but their willingness to pay (WTP) to implement the proposed changes is higher than the farmers’ willingness to accept (WTA). This implies that the proposed changes in current farming practices used for tomato cultivation are economically viable, and hence that market-based approaches to control agricultural pollution may be more effective than regulations in Pakistan

Examining the sociocultural impacts of consanguinity and implications for healthcare : a case study of Pakistanis in Luton

A Thesis submitted to the University of Bedfordshire, in partial fulfilment of the requirements for the degree of Doctor of PhilosophyThis thesis aims to understand the sociocultural aspects of the practice of consanguinity and the implications for healthcare. Consanguinity refers to intra-familial marriage and is commonly used to refer to cousin marriage. While consanguinity remains a global phenomenon, in the recent past, it has mostly been associated with non-Western populations, and has become a taboo in Western culture. Consanguinity is linked with negative health outcomes, mostly due to genetic disorders, although the extent of this link remains debatable. In the UK, consanguinity is linked mostly with the Pakistani community, which also have an overrepresentation of children with genetic disorders. In Luton, local health reports have suggested that consanguinity in the large Pakistani community plays a role in increased infant deaths. This makes Luton and the local Pakistani community, ideally placed for understanding the practice of consanguinity and the implications for healthcare. This thesis is conceptually grounded within a constructionist approach to understanding consanguinity with a critical analysis based on theories of discourse and power and knowledge. A qualitative research design was employed using an instrumental case study approach which focused on understanding consanguinity through Luton’s Pakistani community. Three main sample groups were selected, members of the Pakistani community who are not married to their cousins and are defined as lay members in this research, members of the Pakistani community in consanguineous marriages, and local service providers (primary and secondary care)

Effect of an Inclined Magnetic Field on the Flow of Nanofluids in a Tapered Asymmetric Porous Channel with Heat Source/Sink and Chemical Reaction

This article deals with the effect of an inclined magnetic field with heat source/sink on the flow of nanofluids in a tapered asymmetric porous channel. Effect of chemical reaction has been taken into account. The blood is considered as an incompressible electrically conducting viscous fluid. The assumption of low Reynolds number and long wave length approximations has been adopted. Exact solutions for dimensionless axial velocity, concentration and temperature profile are obtained analytically. The obtained results are displayed and discussed in detail with the help of graphs for the variation of different emerging flow parameters