Cold-climate nitrification on plastic media trickling filters

The accuracy with which cold-climate nitrification performance in structured, plastic media trickling filters can be predicted and the ability to maintain stable operation are governed by the interaction of properties of the wastewater, properties of the media, and mechanical operating parameters;A pilot-scale investigation of cold-climate, separate-stage nitrification in structured, plastic media trickling filters was conducted at the Ames Water Pollution Control Plant (WPCP). Secondary effluent from the existing, overloaded WPCP was treated in the pilot-scale nitrifying biofilter. Pretreatment of the Ames WPCP secondary effluent for reduction of carbonaceous oxygen demand carryover was used in the latter half of the study;Nitrifying biofilter performance was observed for two wastewater application methods, continuous dosing and intermittent dosing, with average hydraulic loading rates ranging from 0.5 to 1.9 l/sq. m (.) s. Two types of cross-flow media were used: (1) 45 degree media with a specific surface area of 98 sq. m/cu. m in the pretreatment trickling filter and (2) 60 degree media with a specific surface area of 138 sq. m/cu. m in the nitrifying biofilter. Nitrification performance was monitored for various bulk liquid chemical oxgyen demand and dissolved oxygen conditions;Dissolved oxygen was shown to be a critical factor in nitrifying biofilter performance. Intermittent dosing and high hydraulic loading rates were shown to be detrimental to cold-climate nitrification performance. Filterable COD was shown to affect nitrification at lower hydraulic loading rates, but not at higher hydraulic loading rates. Transient, partial plugging of the 60 degree cross-flow media was suggested by erratic nitrification performance of individual segments of the nitrifying biofilter media for time periods up to six weeks;Study results were used to improve empirical design curves and to evaluate the implications of process flow schemes and operating parameters. The accuracies of two proposed methods of calculating the effective area of structured, plastic media were evaluated

Hysterics

Hysterics is an eclectic collection of women named and un-named, who find their voices in eleven short stories and six pieces of flash fiction. Hysterics is a fit of fiction, an investigation into the experiences of women, more so the experiences of being a woman. It is the result of pressing on the forehead, of thoughts emerging from forbidden places

Practicing what we preach: Assessing communication center client and staff perspectives of positive communication conferencing practices

Using Mirivel's (2014) Positive Communication Model as a communication center conferencing training framework, both clients and staff were surveyed to determine  to what extent positive communication behaviors were present in communication center client/staff interactions as well as to what extent center staff self-perceptions of positive communication conferencing behaviors align with client perceptions of staff behaviors. Overall, all positive communication behaviors were present in interactions and client and staff perceptions closely aligned. The findings support the use of the Positive Communication Model as a useful framework for training communication center staff on effective conferencing behaviors

Activated Sludge and Other Aerobic Suspended Culture Processes

© 2011 by the authors. A review of the literature published in 2008, 2009 and 2010 relating to activated sludge treatment of wastewater is presented. The review considers information on the topics of modeling and kinetics; process microbiology; nitrogen and phosphorus removal; treatment and effects of xenobiotics; oxygen transfer; and solids separation

Parents' perceptions of their older child's behavior in response to the birth of a sibling

The purpose of this study was to investigate parents' perceptions of their first-born only child's behavior in response to the birth of a second-born sibling. The following major areas were identified for study both before and after the birth of the newborn: (a) parental perceptions of sibling behaviors; (b) parental perceptions of newborn behaviors; and (c) parental perceptions of self behaviors;Subjects were 70 parent couples who were expecting the birth of their second child. The siblings, 32 girls and 38 boys, were 15 to 74 months of age. Questionnaires were completed by the couples during the last trimester of pregnancy and when the newborn was approximately four weeks old;Frequencies and percentages of close-ended items on the two questionnaire sets were calculated. Open-ended responses were grouped. A correlation matrix of all variables was generated. A difference score was calculated for four of the inventories and correlated with other variables. Scattergrams illustrated the responses between mothers and fathers;Significant correlations were found between parents' responses and sibling age and between several factors of parental behaviors and perceived behaviors of the sibling. Parents' expectations and observations of newborn behaviors were related also. Sibling class attendance and perceived behaviors of the sibling after the birth of the newborn were not related. There was a relationship between sibling class attendance and several parental behaviors;The scattergrams indicated strong agreement between mothers and fathers, with generally higher expectations of sibling behaviors before the birth of the newborn than observations after the birth. Mothers showed no pattern for expectations and observations of newborn behaviors, while fathers had higher expectations. Higher parental expectations for newborns correlated positively with desirable newborn behaviors. Parents self-expectations were much higher than self-observations. Three areas of positive sibling behaviors and five areas of negative sibling behaviors were reported in the open-ended questions. This study indicates many variables for further study of the sibling relationship and parent-sibling-newborn interactions.</p

Cold-climate nitrification on plastic media trickling filters

The accuracy with which cold-climate nitrification performance in structured, plastic media trickling filters can be predicted and the ability to maintain stable operation are governed by the interaction of properties of the wastewater, properties of the media, and mechanical operating parameters;A pilot-scale investigation of cold-climate, separate-stage nitrification in structured, plastic media trickling filters was conducted at the Ames Water Pollution Control Plant (WPCP). Secondary effluent from the existing, overloaded WPCP was treated in the pilot-scale nitrifying biofilter. Pretreatment of the Ames WPCP secondary effluent for reduction of carbonaceous oxygen demand carryover was used in the latter half of the study;Nitrifying biofilter performance was observed for two wastewater application methods, continuous dosing and intermittent dosing, with average hydraulic loading rates ranging from 0.5 to 1.9 l/sq. m (.) s. Two types of cross-flow media were used: (1) 45 degree media with a specific surface area of 98 sq. m/cu. m in the pretreatment trickling filter and (2) 60 degree media with a specific surface area of 138 sq. m/cu. m in the nitrifying biofilter. Nitrification performance was monitored for various bulk liquid chemical oxgyen demand and dissolved oxygen conditions;Dissolved oxygen was shown to be a critical factor in nitrifying biofilter performance. Intermittent dosing and high hydraulic loading rates were shown to be detrimental to cold-climate nitrification performance. Filterable COD was shown to affect nitrification at lower hydraulic loading rates, but not at higher hydraulic loading rates. Transient, partial plugging of the 60 degree cross-flow media was suggested by erratic nitrification performance of individual segments of the nitrifying biofilter media for time periods up to six weeks;Study results were used to improve empirical design curves and to evaluate the implications of process flow schemes and operating parameters. The accuracies of two proposed methods of calculating the effective area of structured, plastic media were evaluated.</p

Hysterics

Hysterics is an eclectic collection of women named and un-named, who find their voices in eleven short stories and six pieces of flash fiction. Hysterics is a fit of fiction, an investigation into the experiences of women, more so the experiences of being a woman. It is the result of "pressing on the forehead," of thoughts emerging from forbidden places.</p