title: Settling of Bentonite Particles in Gelatin Solutions for Stickwater Treatment

authors: Shamsuddin, Rashid M.

subjects: Science & Technology

abstract: The settling of calcium and sodium bentonite coated with adsorbed protein from gelatin solutions was investigated across pH 3 to 9. The particle settling or sedimentation was achieved at acidic environment regardless of the amount of protein adsorbed by the particles. The settling is attributed to the formation of “house of cards” structure by bentonite platelets and it is strongly influenced by solution pH. The collapse of this formation resulted in floc formation or particle suspension where no settling can be observed. Few possible settling mechanisms were proposed based on the charge balance and interactions between bentonite platelets and protein molecules in the system. The findings are intended for treatment of gelatin-rich stickwater (meat rendering waste water) using bentonite as low-cost adsorbent. Integrating adsorption and settling into one unit operation has multiple benefits; reducing BOD by removing the proteins and bentonite is directly modified with organics and can be recovered via gravity settling for composite additive application.

text: Settling of Bentonite Particles in Gelatin Solutions for Stickwater Treatment The settling of calcium and sodium bentonite coated with adsorbed protein from gelatin solutions was investigated across pH 3 to 9. The particle settling or sedimentation was achieved at acidic environment regardless of the amount of protein adsorbed by the particles. The settling is attributed to the formation of “house of cards” structure by bentonite platelets and it is strongly influenced by solution pH. The collapse of this formation resulted in floc formation or particle suspension where no settling can be observed. Few possible settling mechanisms were proposed based on the charge balance and interactions between bentonite platelets and protein molecules in the system. The findings are intended for treatment of gelatin-rich stickwater (meat rendering waste water) using bentonite as low-cost adsorbent. Integrating adsorption and settling into one unit operation has multiple benefits; reducing BOD by removing the proteins and bentonite is directly modified with organics and can be recovered via gravity settling for composite additive application.

year: 2016

title: Change in heat capacity for enzyme catalysis determines temperature dependence of enzyme catalyzed ratesnzyme Catalyzed Rates

authors: Hobbs, Joanne K.

abstract: The increase in enzymatic rates with temperature up to an optimum temperature (Topt) is widely attributed to classical Arrhenius behavior, with the decrease in enzymatic rates above Topt ascribed to protein denaturation and/or aggregation. This account persists despite many investigators noting that denaturation is insufficient to explain the decline in enzymatic rates above Topt. Here we show that it is the change in heat capacity associated with enzyme catalysis (ΔC‡p) and its effect on the temperature dependence of ΔG‡ that determines the temperature dependence of enzyme activity. Through mutagenesis, we demonstrate that the Topt of an enzyme is correlated with ΔC‡p and that changes to ΔC‡p are sufficient to change Topt without affecting the catalytic rate. Furthermore, using X-ray crystallography and molecular dynamics simulations we reveal the molecular details underpinning these changes in ΔC‡p. The influence of ΔC‡p on enzymatic rates has implications for the temperature dependence of biological rates from enzymes to ecosystems.

text: Change in heat capacity for enzyme catalysis determines temperature dependence of enzyme catalyzed ratesnzyme Catalyzed Rates The increase in enzymatic rates with temperature up to an optimum temperature (Topt) is widely attributed to classical Arrhenius behavior, with the decrease in enzymatic rates above Topt ascribed to protein denaturation and/or aggregation. This account persists despite many investigators noting that denaturation is insufficient to explain the decline in enzymatic rates above Topt. Here we show that it is the change in heat capacity associated with enzyme catalysis (ΔC‡p) and its effect on the temperature dependence of ΔG‡ that determines the temperature dependence of enzyme activity. Through mutagenesis, we demonstrate that the Topt of an enzyme is correlated with ΔC‡p and that changes to ΔC‡p are sufficient to change Topt without affecting the catalytic rate. Furthermore, using X-ray crystallography and molecular dynamics simulations we reveal the molecular details underpinning these changes in ΔC‡p. The influence of ΔC‡p on enzymatic rates has implications for the temperature dependence of biological rates from enzymes to ecosystems.

year: 2013

title: A life-history analysis of achievement of Māori and Pacific Island students at the Church College of New Zealand

authors: Solomon, Tereapii Elinora

subjects: Church College

abstract: The Church College of New Zealand is a private co-educational secondary school located near Hamilton, New Zealand and is sponsored by the Church of Jesus Christ of Latter-day Saints.  Since its opening in 1958, it has hosted a large population of Polynesian students, in particular Māori.  The questions that this thesis addresses centre on the nature, history and reasons for what seems to be a disproportionately higher level of achievement amongst Māori and Pacific Island students at Church College than in New Zealand more broadly.  Through a life-history approach to research, this thesis provides an overview of the rich history behind the building of the Church College, and highlights the experiences of successful graduates over three particular timeframes - 1951-1969, 1970-1989 and the 1990s.  

A major contributing factor to the success of the students at Church College is an environment where both religious and cultural values of students are reaffirmed and considered normal.  For some students, Church College provided an environment that validated what students were being taught in their own homes.  For others, it provided a refuge from a conflicted home.  With the growing pressures of social problems within the wider community for many Māori and Pacific Island families, the school environment of  the Church College was a key factor in providing stability  and security for some students at the College.

On June 29 2006, an announcement was made by leaders of the Church of Jesus Christ of Latter-day Saints of the phased out closure of Church College beginning in the year 2007 and eventually closing at the end of the year 2009. With Māori and Pacific Island students so under-represented in achievement and participation in education settings in New Zealand, the announcement of the closure provided an opportunity to highlight some of the successes experienced at the Church College of New Zealand.

text: A life-history analysis of achievement of Māori and Pacific Island students at the Church College of New Zealand The Church College of New Zealand is a private co-educational secondary school located near Hamilton, New Zealand and is sponsored by the Church of Jesus Christ of Latter-day Saints.  Since its opening in 1958, it has hosted a large population of Polynesian students, in particular Māori.  The questions that this thesis addresses centre on the nature, history and reasons for what seems to be a disproportionately higher level of achievement amongst Māori and Pacific Island students at Church College than in New Zealand more broadly.  Through a life-history approach to research, this thesis provides an overview of the rich history behind the building of the Church College, and highlights the experiences of successful graduates over three particular timeframes - 1951-1969, 1970-1989 and the 1990s.  

A major contributing factor to the success of the students at Church College is an environment where both religious and cultural values of students are reaffirmed and considered normal.  For some students, Church College provided an environment that validated what students were being taught in their own homes.  For others, it provided a refuge from a conflicted home.  With the growing pressures of social problems within the wider community for many Māori and Pacific Island families, the school environment of  the Church College was a key factor in providing stability  and security for some students at the College.

On June 29 2006, an announcement was made by leaders of the Church of Jesus Christ of Latter-day Saints of the phased out closure of Church College beginning in the year 2007 and eventually closing at the end of the year 2009. With Māori and Pacific Island students so under-represented in achievement and participation in education settings in New Zealand, the announcement of the closure provided an opportunity to highlight some of the successes experienced at the Church College of New Zealand.

year: 2008