title: The prospectors’ claim at Te Aroha

authors: Hart, Philip

abstract: High up the mountain, on the edge of a precipice, the Prospectors’ Claim was at first examined only on the surface, producing some valuable stone. After the goldfield was proclaimed, two tunnels were driven under the supervision of experienced miners, but despite encouraging signs, no reef was struck. Once the first parcel was tested in Thames in early December, the owners realized the value of their ore was less than anticipated, and when a crushing was made in the new Te Aroha battery in 1881 the returns were lower than expected. Consequently, mining ceased, and the ground was abandoned. 
In September 1882 four experienced miners acquired part of the ground as the optimistically named Golden Hill, but after obtaining the usual ‘encouraging’ results their work came to nothing. There was some interest in the ground subsequently, but a lode was never found, and seemingly will never be found.

text: The prospectors’ claim at Te Aroha High up the mountain, on the edge of a precipice, the Prospectors’ Claim was at first examined only on the surface, producing some valuable stone. After the goldfield was proclaimed, two tunnels were driven under the supervision of experienced miners, but despite encouraging signs, no reef was struck. Once the first parcel was tested in Thames in early December, the owners realized the value of their ore was less than anticipated, and when a crushing was made in the new Te Aroha battery in 1881 the returns were lower than expected. Consequently, mining ceased, and the ground was abandoned. 
In September 1882 four experienced miners acquired part of the ground as the optimistically named Golden Hill, but after obtaining the usual ‘encouraging’ results their work came to nothing. There was some interest in the ground subsequently, but a lode was never found, and seemingly will never be found.

year: 2016

title: Hybrid Solid-State Hydrogen Storage Materials

authors: Benge, Kathryn Ruth

subjects: Ammonia Borane

abstract: This thesis investigates the chemistry of ammonia borane (NH₃BH₃) relevant to the development of hydrogen storage systems for vehicular applications.
Because of its high hydrogen content and low molecular weight ammonia borane has the potential to meet stringent gravimetric hydrogen storage targets of >9 wt%. Two of the three moles of H₂ in ammonia borane can be released under relatively mild conditions, with the highest gravimetric yield obtained in the solid-state. However, ammonia borane does not deliver sufficient H₂ at practical temperatures and the products formed upon H₂ loss are not amenable to regeneration back to the parent compound.
The literature synthesis of ammonia borane was modified to facilitate large scale synthesis, and the deuterated analogues ND₃BH₃ and NH₃BD₃ were prepared for the purpose of mechanistic studies.
The effect of lithium amide on the kinetics of dehydrogenation of ammonia borane was assessed by means of solid-state reaction in a series of specific molar ratios. Upon mixing lithium amide and ammonia borane, an exothermic reaction ensued resulting in the formation of a weakly bound adduct with an H₂N...BH₃-NH₃ environment. Thermal decomposition at or above temperatures of 50◦C of this phase was shown to liberate >9 wt% H₂. The mechanism of hydrogen evolution was investigated by means of reacting lithium amide and deuterated ammonia borane isotopologues, followed by analysis of the isotopic composition of evolved gaseous products by mass spectrometry. From these results, an intermolecular multi-step reaction mechanism was proposed, with the rates of the first stage strongly dependent on the concentration of lithium amide present. Compounds exhibiting a BN₃ environment (identi-fied by means of solid-state ¹¹B NMR spectroscopy) were formed during the first stage, and subsequently cross link to form a non-volatile solid. Further heating of this non-volatile solid phase ultimately resulted in the formation of crystalline Li₃BN₂ - identified by means of powder X-ray diffractometry.
This compound has been identified as a potential hydrogen storage material due to its lightweight and theoretically high hydrogen content. It may also be amenable to hydrogen re-absorption.
The LiNH₂/CH₃NH₂BH₃ system was also investigated. Thermal decomposition occurred through the same mechanism described for the LiNH₂/NH₃BH₃ system to theoretically evolve >8 wt% hydrogen. The gases evolved on thermal decomposition were predominantly H₂ with traces of methane detected by mass spectrometry.

text: Hybrid Solid-State Hydrogen Storage Materials This thesis investigates the chemistry of ammonia borane (NH₃BH₃) relevant to the development of hydrogen storage systems for vehicular applications.
Because of its high hydrogen content and low molecular weight ammonia borane has the potential to meet stringent gravimetric hydrogen storage targets of >9 wt%. Two of the three moles of H₂ in ammonia borane can be released under relatively mild conditions, with the highest gravimetric yield obtained in the solid-state. However, ammonia borane does not deliver sufficient H₂ at practical temperatures and the products formed upon H₂ loss are not amenable to regeneration back to the parent compound.
The literature synthesis of ammonia borane was modified to facilitate large scale synthesis, and the deuterated analogues ND₃BH₃ and NH₃BD₃ were prepared for the purpose of mechanistic studies.
The effect of lithium amide on the kinetics of dehydrogenation of ammonia borane was assessed by means of solid-state reaction in a series of specific molar ratios. Upon mixing lithium amide and ammonia borane, an exothermic reaction ensued resulting in the formation of a weakly bound adduct with an H₂N...BH₃-NH₃ environment. Thermal decomposition at or above temperatures of 50◦C of this phase was shown to liberate >9 wt% H₂. The mechanism of hydrogen evolution was investigated by means of reacting lithium amide and deuterated ammonia borane isotopologues, followed by analysis of the isotopic composition of evolved gaseous products by mass spectrometry. From these results, an intermolecular multi-step reaction mechanism was proposed, with the rates of the first stage strongly dependent on the concentration of lithium amide present. Compounds exhibiting a BN₃ environment (identi-fied by means of solid-state ¹¹B NMR spectroscopy) were formed during the first stage, and subsequently cross link to form a non-volatile solid. Further heating of this non-volatile solid phase ultimately resulted in the formation of crystalline Li₃BN₂ - identified by means of powder X-ray diffractometry.
This compound has been identified as a potential hydrogen storage material due to its lightweight and theoretically high hydrogen content. It may also be amenable to hydrogen re-absorption.
The LiNH₂/CH₃NH₂BH₃ system was also investigated. Thermal decomposition occurred through the same mechanism described for the LiNH₂/NH₃BH₃ system to theoretically evolve >8 wt% hydrogen. The gases evolved on thermal decomposition were predominantly H₂ with traces of methane detected by mass spectrometry.

year: 2008

title: The Aroha block from 1880 onwards

authors: Hart, Philip

abstract: With the discovery of gold in 1880 and the pressure to open the land for mining, there was a need to determine the boundaries of the Ngati Rahiri reserves and to subdivide these amongst the owners. As well, terms for paying goldfields revenue had to be negotiated before the goldfield could be opened, and after its opening the claims of Maori with little or no basis for their claims of ownership had to be investigated. Wairakau reserve, outside the goldfield, was not subdivided until mid-1882, and arguments over the ownership of Tui Pa continued well into the twentieth century. 
At first, sales of Crown land found few takers, especially because the farm sections required draining before they could be developed. Ngati Rahiri reserves were designated as being inalienable, but they could be leased for 21 years, as some portions were, at low rates. Very quickly, officials, who feared Maori would become landless, had to fend off requests to remove restrictions on sale made by owners who in some instances lived far from Te Aroha and who all wanted to obtain money from selling land of little use to them. The indebtedness of some owners led to continued pressure to sell, though often the money they received was wasted. With the fading of the goldfield, miners sought land for farms, and were frustrated at the Crown not purchasing the Ngati Rahiri reserves. 
Land was acquired by the Crown to extend the hot springs domain, and after negotiating improved leases in the Te Aroha township the freehold of this settlement was acquired. Some Maori retained their land, which Pakeha accused them of not improving; Maori requests that the government provide training in farming methods were ignored. By the twentieth century most Ngati Rahiri had become landless, but as many examples illustrate, this was commonly because cash-strapped owners insisted on selling their interests for an immediate financial return.

text: The Aroha block from 1880 onwards With the discovery of gold in 1880 and the pressure to open the land for mining, there was a need to determine the boundaries of the Ngati Rahiri reserves and to subdivide these amongst the owners. As well, terms for paying goldfields revenue had to be negotiated before the goldfield could be opened, and after its opening the claims of Maori with little or no basis for their claims of ownership had to be investigated. Wairakau reserve, outside the goldfield, was not subdivided until mid-1882, and arguments over the ownership of Tui Pa continued well into the twentieth century. 
At first, sales of Crown land found few takers, especially because the farm sections required draining before they could be developed. Ngati Rahiri reserves were designated as being inalienable, but they could be leased for 21 years, as some portions were, at low rates. Very quickly, officials, who feared Maori would become landless, had to fend off requests to remove restrictions on sale made by owners who in some instances lived far from Te Aroha and who all wanted to obtain money from selling land of little use to them. The indebtedness of some owners led to continued pressure to sell, though often the money they received was wasted. With the fading of the goldfield, miners sought land for farms, and were frustrated at the Crown not purchasing the Ngati Rahiri reserves. 
Land was acquired by the Crown to extend the hot springs domain, and after negotiating improved leases in the Te Aroha township the freehold of this settlement was acquired. Some Maori retained their land, which Pakeha accused them of not improving; Maori requests that the government provide training in farming methods were ignored. By the twentieth century most Ngati Rahiri had become landless, but as many examples illustrate, this was commonly because cash-strapped owners insisted on selling their interests for an immediate financial return.

year: 2016