title: Chemical and rheological aspects of gel formation in the California Mastitis Test

authors: Whyte, David

subjects: mastitis

abstract: The rheological properties of the CMT gel were analysed. Data are presented to demonstrate that the gel is a non-homogenous, visco-elastic, non-Newtonian fluid with rheopectic, and rheodestructive behaviour. The fundamental chemistry of the CMT is reviewed and a modified theory of gel formation is presented. The implications of the rheological properties and modified theory of gel formation for an automatic sensor are discussed.

text: Chemical and rheological aspects of gel formation in the California Mastitis Test The rheological properties of the CMT gel were analysed. Data are presented to demonstrate that the gel is a non-homogenous, visco-elastic, non-Newtonian fluid with rheopectic, and rheodestructive behaviour. The fundamental chemistry of the CMT is reviewed and a modified theory of gel formation is presented. The implications of the rheological properties and modified theory of gel formation for an automatic sensor are discussed.

year: 2005

title: Using ESI-MS to investigate the organometallic compound Cp₂Ti(SC₆H₄CO₂) and closely related compounds

authors: Song, Kai

subjects: ESI-MS

abstract: This thesis reports investigations on the electrospray ionisation mass spectrometric (ESI-MS) behaviour of some metallocene complexes of titanium and molybdenum. The ESI-MS behaviour of titanocene dichloride (Cp₂TiCl₂) compound, which is has shown of interest as an anticancer agent was investigated. Cp₂TiCl₂ was dissolved in various solvents and spectra were recorded at various capillary exit voltages from 60 V to 250 V. Bis(ethylcyclopentadienyl) dichloridotitanium(IV) was also studied via ESI-MS. Results indicated clearly some main species like [Cp₂TiH]⁺, [Cp₂Ti(OCH₃)]⁺ and [Cp₂Ti(OCH₃)₂+H]⁺ were observed. When the capillary exit voltage was greater than 150 V species containing two Ti centres like [Cp₄Ti₂(OCH₃)₂Cl]⁺, [Cp₄Ti₂(OCH₃)₃Cl+H]⁺ and [(Cp₂Ti(OCH₃)₂+H⁺)₂+Cl]⁻ disappeared and titanocene(III) species [Cp₂Ti(CH₃OH)]⁺ was observed which indicated reduction of titanium(IV) during ESI-MS analysis. Larger ions which contain three or more Ti centres were not observed. 

The main focus of this thesis was to investigate the chemistry and characterisation of the organometallic compound bis(cyclopentadienyl) thiosalicylatotitanium(IV) (Cp₂Ti(tsal) tsal = SC₆H₄CO₂). A further experiment was done to run the spectrum of a mixed solution of Cp₂TiCl₂ and Cp₂Ti(tsal) in CH₃OH to investigate the possibility of the tsal ligand bridging two Cp₂Ti centres. Characterisation of Cp₂Ti(tsal) using ESI mass spectrometry in the presence of added alkali metal salts and the reactivity of Cp₂Ti(tsal) towards soft electrophile was also studied.

At the same time, a new complex bis(ethylcyclopentadienyl) thiosalicylatotitanium(IV) ((EtCp)₂Ti(tsal)) was synthesised and studied by ESI-MS. Comparison of the ESI-MS spectra of Cp₂Ti(tsal) with those of (EtCp)₂Ti(tsal) was used to confirm the identity of some unknown species. This new complex was characterised by elemental analysis, melting point, nuclear magnetic resonance (NMR) and infra-red (IR) spectroscopy.

Finally the molybdocene dichloride (Cp₂MoCl₂) compound was studied by ESI-MS. The closely related compound bis(cyclopentadienyl) thiosalicylatomolybdenum(IV)  (Cp₂Mo(tsal)) was synthesised and characterised by ESI-MS, melting point, NMR and IR spectroscopy. Less species can be observed in the Mo system than in the Ti system. Most species in the Mo system contained a Cl ligand.

text: Using ESI-MS to investigate the organometallic compound Cp₂Ti(SC₆H₄CO₂) and closely related compounds This thesis reports investigations on the electrospray ionisation mass spectrometric (ESI-MS) behaviour of some metallocene complexes of titanium and molybdenum. The ESI-MS behaviour of titanocene dichloride (Cp₂TiCl₂) compound, which is has shown of interest as an anticancer agent was investigated. Cp₂TiCl₂ was dissolved in various solvents and spectra were recorded at various capillary exit voltages from 60 V to 250 V. Bis(ethylcyclopentadienyl) dichloridotitanium(IV) was also studied via ESI-MS. Results indicated clearly some main species like [Cp₂TiH]⁺, [Cp₂Ti(OCH₃)]⁺ and [Cp₂Ti(OCH₃)₂+H]⁺ were observed. When the capillary exit voltage was greater than 150 V species containing two Ti centres like [Cp₄Ti₂(OCH₃)₂Cl]⁺, [Cp₄Ti₂(OCH₃)₃Cl+H]⁺ and [(Cp₂Ti(OCH₃)₂+H⁺)₂+Cl]⁻ disappeared and titanocene(III) species [Cp₂Ti(CH₃OH)]⁺ was observed which indicated reduction of titanium(IV) during ESI-MS analysis. Larger ions which contain three or more Ti centres were not observed. 

The main focus of this thesis was to investigate the chemistry and characterisation of the organometallic compound bis(cyclopentadienyl) thiosalicylatotitanium(IV) (Cp₂Ti(tsal) tsal = SC₆H₄CO₂). A further experiment was done to run the spectrum of a mixed solution of Cp₂TiCl₂ and Cp₂Ti(tsal) in CH₃OH to investigate the possibility of the tsal ligand bridging two Cp₂Ti centres. Characterisation of Cp₂Ti(tsal) using ESI mass spectrometry in the presence of added alkali metal salts and the reactivity of Cp₂Ti(tsal) towards soft electrophile was also studied.

At the same time, a new complex bis(ethylcyclopentadienyl) thiosalicylatotitanium(IV) ((EtCp)₂Ti(tsal)) was synthesised and studied by ESI-MS. Comparison of the ESI-MS spectra of Cp₂Ti(tsal) with those of (EtCp)₂Ti(tsal) was used to confirm the identity of some unknown species. This new complex was characterised by elemental analysis, melting point, nuclear magnetic resonance (NMR) and infra-red (IR) spectroscopy.

Finally the molybdocene dichloride (Cp₂MoCl₂) compound was studied by ESI-MS. The closely related compound bis(cyclopentadienyl) thiosalicylatomolybdenum(IV)  (Cp₂Mo(tsal)) was synthesised and characterised by ESI-MS, melting point, NMR and IR spectroscopy. Less species can be observed in the Mo system than in the Ti system. Most species in the Mo system contained a Cl ligand.

year: 2019

title: Assessment of effects of proposed treated wastewater discharge to the Te Arikiroa Thermal Channel and Sulphur Bay (Lake Rotorua)

authors: Dada, Ayokunle Christopher

abstract: After 2019, irrigation operations at the Land Treatment System (LTS) in the Whakarewarewa Forest are scheduled to cease. A number of options and locations have been considered for the discharge of the treated wastewater when the current discharge consent ceases. Following consultations and technical assessments, the preferred option of Rotorua Lakes Council is to upgrade the existing plant to a full Membrane Bioreactor Plant with the addition of an Ultraviolet Disinfection System (or alternative treatment to achieve an equivalent performance in terms of treated wastewater quality). Under this arrangement, wastewater would be subjected to biological, chemical and physical treatment processes, and the treated wastewater discharged through Te Arikiroa Thermal Channel to Sulphur Bay. Rotorua Lakes Council is thus undertaking an environmental impact assessment study to determine the effects of discharging treated wastewater to the thermal channel and Puarenga Bay (Lake Rotorua), with particular reference to aesthetic, water quality and ecological considerations. These considerations include potential effects related to faecal indicator bacteria, nutrient concentrations, metals, dissolved oxygen, and taonga species (native species of cultural significance).
The assessment focused on:
(i)	The projected treated wastewater characteristics;

(ii)	Existing conditions of the receiving water;

(iii)	The sensitivity of the receiving water and the impact of the proposed discharge on water quality and taonga species (native species of cultural significance) in Te Arikiroa Thermal Channel and Sulphur Bay.

The main techniques used to inform the assessment in this study were:
1) Analysis of historical water quality data, 2011-2014;
2) Collection of additional water quality data at Te Arikiroa Thermal Channel and Sulphur Bay and along a transect to quantify spatial variability (sampling in 2016 and 2017);
3) Mass balance dilution modelling to predict water quality in the Te Arikiroa Thermal Channel and Sulphur Bay (Lake Rotorua), at a site outside of the assumed mixing zone;
4) Lake ecosystem modelling conducted by Abell et al. (2015) to assess effects related to eutrophication;
5) Background review of biological information and field investigations for taonga species at Sulphur Bay and Te Arikiroa Thermal Channel (2017).

text: Assessment of effects of proposed treated wastewater discharge to the Te Arikiroa Thermal Channel and Sulphur Bay (Lake Rotorua) After 2019, irrigation operations at the Land Treatment System (LTS) in the Whakarewarewa Forest are scheduled to cease. A number of options and locations have been considered for the discharge of the treated wastewater when the current discharge consent ceases. Following consultations and technical assessments, the preferred option of Rotorua Lakes Council is to upgrade the existing plant to a full Membrane Bioreactor Plant with the addition of an Ultraviolet Disinfection System (or alternative treatment to achieve an equivalent performance in terms of treated wastewater quality). Under this arrangement, wastewater would be subjected to biological, chemical and physical treatment processes, and the treated wastewater discharged through Te Arikiroa Thermal Channel to Sulphur Bay. Rotorua Lakes Council is thus undertaking an environmental impact assessment study to determine the effects of discharging treated wastewater to the thermal channel and Puarenga Bay (Lake Rotorua), with particular reference to aesthetic, water quality and ecological considerations. These considerations include potential effects related to faecal indicator bacteria, nutrient concentrations, metals, dissolved oxygen, and taonga species (native species of cultural significance).
The assessment focused on:
(i)	The projected treated wastewater characteristics;

(ii)	Existing conditions of the receiving water;

(iii)	The sensitivity of the receiving water and the impact of the proposed discharge on water quality and taonga species (native species of cultural significance) in Te Arikiroa Thermal Channel and Sulphur Bay.

The main techniques used to inform the assessment in this study were:
1) Analysis of historical water quality data, 2011-2014;
2) Collection of additional water quality data at Te Arikiroa Thermal Channel and Sulphur Bay and along a transect to quantify spatial variability (sampling in 2016 and 2017);
3) Mass balance dilution modelling to predict water quality in the Te Arikiroa Thermal Channel and Sulphur Bay (Lake Rotorua), at a site outside of the assumed mixing zone;
4) Lake ecosystem modelling conducted by Abell et al. (2015) to assess effects related to eutrophication;
5) Background review of biological information and field investigations for taonga species at Sulphur Bay and Te Arikiroa Thermal Channel (2017).

year: 2018