Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 263 for “"alkalinity"”.
-
Automated alkalinity sensing system
… automated benchtop measuring system for total alkalinity, one of the important parameters for monitoring marine carbonate chemistry. This system addresses the need for a low-cost alkalinity sensing system that can be deployed in great numbers to provide the large data sets needed for to measure …
-
Studies of moisture and alkalinity in self-levelling flooring compounds
… This is better provided by an SLC of lower alkalinity.
-
Balancing ammonia and alkalinity for nitrification at Walnut Creek Wastewater Treatment Plant
… process used to treat ammonia, consumes alkalinity, which makes it difficult to properly treat ammonia while still maintaining the pH above the required discharge level of pH 6. Operators have looked to the addition of chemicals to supplement alkalinity; one creative alkalinity source was …
-
Monitoring the Stability of Anaerobic Digestion Using a Novel On-line Bicarbonate Alkalinity Monitor
… species determining pH buffering capacity, or alkalinity. In anaerobic digesters the bicarbonate levels should be within 10 to 50mM to ensure stable operation. Bicarbonate concentration in wastewater treatment processes is routinely measured off-line by titration with standard acid to a set pH …
-
Seasonality of the marine carbonate system in the southern Benguela nutrient stoichiometry, alkalinity production, and CO flux
… the processes driving bulk stoichiometry, alkalinity production on the continental shelf, and the air-sea flux of CO2. Monthly samples were taken along the St. Helena Bay Monitoring Line in the southern Benguela for ten of the months in 2010. Samples were analysed for dissolved inorganic …
-
Theoretical copper sulfate dosing;the effect of alkalinity and humic acid on ionic copper toxicity to algae
… to Virginia freshwater. Concentrations of alkalinity and humic acid were varied to study their effect on percentages of ionic copper available. Long-term (2 weeks) growth-rate studies were performed to study the effect of humic acid on the toxicity of ionic copper to algae. Some protection …
-
Prospective retarders for alkali-activated slag: stability at high alkalinity, effects on setting behavior and strength of paste
Alternate binders are becoming essential to counteract the carbon emissions caused by manufacture of ordinary Portland cements. Geopolymers or alkali-activated systems with precursors as fly ash, slag or metakaolin, or a mixture of these, are possible substitutes. There are several hindrances to …
-
Water Quality Based Design Guidelines for Successive Alkalinity-Producing Systems Used in the Treatment of Acidic Mine Drainage
Successive Alkalinity-Producing Systems (SAPS) have proven to be a viable alternative to chemical treatment for renovating acidic mine drainage (AMD). The lack of water quality based design guidelines, however, is believed to be a cause of the variability of SAPS performance in the field. This …
-
Weak acid/bases and pH control in upflow anaerobic sludge bed reactors
Prior to the investigation into H₂CO₃*alkalinity, each waste (substrate) was studied with respect to its potential for pellet formation. During these feasibility studies, the need emerged for a simple, reliable and accurate method to monitor the H₂CO₃*alkalinity and SCFA concentration in the …
-
Geochemical drivers of Mn removal in drinking water reservoirs under hypolimnetic oxygenation
… geochemical drivers of Mn removal, including pH, alkalinity and the presence of mineral particles. We conducted laboratory experiments and field monitoring at two drinking water reservoirs in southwestern Virginia – Falling Creek Reservoir (FCR) and Carvins Cove Reservoir (CCR). In laboratory …
-
Combined effects of water chemistry, canopy cover, and stream size on benthic macroinvertebrates along a Central Appalachian stream continuum
… to determine if localized variation in alkalinity and canopy cover would modify stream continuum predictions. Localized variation in alkalinity and canopy cover significantly affected macroinvertebrate structure and function and modified stream continuum predictions. Results indicated …
-
Freshwater Endmembers Impacting Carbonate Chemistry in the Mississippi Sound
… on dissolved inorganic carbon (DIC) and total alkalinity (TA) in the Mississippi Sound in order to understand the influence of local rivers that supply alkalinity to the area and buffer against ocean acidification. This area receives large fluxes of freshwater from local rivers, in addition to …
-
Physical and chemical characterization of single atmospheric aerosols: Laboratory studies of interactions of acidic trace gases with sea -salt aerosols, and, Development efforts for an aerosol charging system using a corona discharge
… under a variety of relative humidity and alkalinity conditions was measured. The uptake coefficient varied strongly with changes in relative humidity, time and alkalinity. In addition, oxidation of sulfur dioxide to sulfate in sea-salt aerosols was studied under a variety of alkalinity …
-
Hydrogeological controls of uranium and arsenic mobility in groundwater of the Pine Ridge Reservation, South Dakota
… portions of the Arikaree aquifer. Groundwater alkalinity, sodium, and pH levels increase along flowpaths in the Arikaree aquifer despite rising carbonate mineral saturation indices, indicating that volcanic ash may act as a secondary source of alkalinity in the aquifer. Elevated alkalinity and …
-
Water Quality, Aesthetic, and Corrosion Inhibitor Implications of Newly Installed Cement Mortar Lining Used to Rehabilitate Drinking Water Pipelines
… impacts on disinfectant by-product formation, alkalinity, metal leaching, pH and disinfectant consumption, and odor generation shortly after in-situ installation. The experimental design used a 30-day, coupon immersion procedure that simulated a relined 4-inch diameter pipe located in a …
-
Effects of water chemistry, temperature, gaseous cavitation & phosphate inhibitors on concrete corrosion
… to concrete corrosion control. Under low alkalinity and low pH conditions, considered to be highly aggressive in the literature, we noticed very substantial corrosion of concrete in laboratory experiments. At high pH and high alkalinity conditions, the buildup of scale (e.g., calcium …
-
Evaluation of Zinc Orthophosphate to Control Lead Solder Corrosion in Waters With High Chloride to Sulfate Mass Ratio
… combination of zinc orthophosphate and moderate alkalinity mitigated lead release in testing at two utilities. Either zinc alone or phosphate alone were irrelatively ineffective, but the combination of zinc orthophosphate reduced lead leaching by 54-99% (compared to the control without …
-
Water Quality Variations During Nitrification In Drinking Water Distribution Systems
… oxygen, heterotrophic plate counts (HPCs), pH, alkalinity, and nitrogen species were monitored and found to vary as expected by stoichiometry associated with theoretical biological reactions excepting alkalinity. Nitrification was confirmed in the PDSs. The occurrence in the PDSs was not …
-
Modeling ocean transport and its biogeochemical impacts at global, regional, and sub-meso scales
… through the redistribution of tracers such as alkalinity, nutrients, and carbon. Starting at the large scale in Chapter 2, we use a mesoscale-permitting global ocean model to investigate ocean alkalinity enhancement as a negative emissions technology. We find that local ocean dynamics are …
Page 1 of 14