title: Program Development and Specification Refinement in the Schema Calculus

authors: Henson, Martin C.

subjects: computer science

abstract: We introduce a framework for program development and specification refinement in the schema calculus of Z. We provide illustrative examples outlining the major design decisions based on an interpretation of operation schemas as sets of programs.

text: Program Development and Specification Refinement in the Schema Calculus We introduce a framework for program development and specification refinement in the schema calculus of Z. We provide illustrative examples outlining the major design decisions based on an interpretation of operation schemas as sets of programs.

year: 2000

title: Dinuclear platinum(II) sulfide–thiolate complexes [Pt₂(μ-S)(μ-SR)(PPh₃)₄]⁺ containing fluorinated substituents and the identification of a SC₆F₅ π interaction in the crystal structure of [Pt₂(μ-S)(μ-SCH₂C₆F₅)(PPh₃)₄]BPh₄•2C₆H₆

authors: Henderson, William

subjects: platinum complexes

abstract: Reactions of the platinum(II) sulfido complex [Pt₂(μ-S)₂(PPh₃)₄] with the alkyl iodides ICH₂CH₂(CF₂)nCF₃ (n = 3, 7) gives good yields of the monoalkylated products [Pt₂(μ-S){μ-SCH₂CH₂(CF₂)nCF₃}(PPh₃)₄]⁺, which were isolated as  PF₆⁺or  BPH₄⁻ salts, and characterised by ESI mass spectrometry, NMR spectroscopy and elemental analysis. The complex [Pt₂(μ-S){μ-SCH₂CH₂(CF₂)nCF₃}(PPh₃)₄]⁺ appears to have normal reactivity for this type of complex, namely reaction with Ph₃PAuCl to give [Pt₂(μ-SAuPPh₃){μ-SCH₂CH₂(CF₂)nCF₃}(PPh₃)₄]₂⁺, and reaction with Me₂SO₄ to give [Pt₂(μ-SMe){μ-SCH₂CH₂(CF₂)nCF₃}(PPh₃)₄]₂⁺. Reaction of [Pt₂(μ-S)₂(PPh₃)₄] with C₆F₅CH₂Br gave [Pt₂(μ-S)(μ-SCH₂C₆F₅)(PPh₃)₄]⁺, isolated as BPh₄⁻ its  salt, and characterised by NMR spectroscopy and a single-crystal X-ray structure determination. The C₆F₅ group lies above the {Pt₂S₂} core of the complex as a result of a SC₆F₅ π interaction, in contrast to the published structure of [Pt₂(μ-S)(μ-SCH₂C₆H₅)(PPh₃)₄]PF₆, where the C₆H₅ group projects away from the {Pt₂S₂} core.

text: Dinuclear platinum(II) sulfide–thiolate complexes [Pt₂(μ-S)(μ-SR)(PPh₃)₄]⁺ containing fluorinated substituents and the identification of a SC₆F₅ π interaction in the crystal structure of [Pt₂(μ-S)(μ-SCH₂C₆F₅)(PPh₃)₄]BPh₄•2C₆H₆ Reactions of the platinum(II) sulfido complex [Pt₂(μ-S)₂(PPh₃)₄] with the alkyl iodides ICH₂CH₂(CF₂)nCF₃ (n = 3, 7) gives good yields of the monoalkylated products [Pt₂(μ-S){μ-SCH₂CH₂(CF₂)nCF₃}(PPh₃)₄]⁺, which were isolated as  PF₆⁺or  BPH₄⁻ salts, and characterised by ESI mass spectrometry, NMR spectroscopy and elemental analysis. The complex [Pt₂(μ-S){μ-SCH₂CH₂(CF₂)nCF₃}(PPh₃)₄]⁺ appears to have normal reactivity for this type of complex, namely reaction with Ph₃PAuCl to give [Pt₂(μ-SAuPPh₃){μ-SCH₂CH₂(CF₂)nCF₃}(PPh₃)₄]₂⁺, and reaction with Me₂SO₄ to give [Pt₂(μ-SMe){μ-SCH₂CH₂(CF₂)nCF₃}(PPh₃)₄]₂⁺. Reaction of [Pt₂(μ-S)₂(PPh₃)₄] with C₆F₅CH₂Br gave [Pt₂(μ-S)(μ-SCH₂C₆F₅)(PPh₃)₄]⁺, isolated as BPh₄⁻ its  salt, and characterised by NMR spectroscopy and a single-crystal X-ray structure determination. The C₆F₅ group lies above the {Pt₂S₂} core of the complex as a result of a SC₆F₅ π interaction, in contrast to the published structure of [Pt₂(μ-S)(μ-SCH₂C₆H₅)(PPh₃)₄]PF₆, where the C₆H₅ group projects away from the {Pt₂S₂} core.

year: 2011

title: The alienation of the Opuatia block: A GIS case study report written for Counting our Tūpuna

authors: Whitehead, Jesse

abstract: This report provides an analysis and visualisation of the fragmentation and alienation of the Opuatia block (Opuatia hereafter), as well as changes in its ownership and geographic structure since 1866.
The three main aims are to quantify the amount of Opuatia remaining in Ngāti Tiipa ownership at the end of each decade, identifying critical moments in time, and highlighting the processes through which Opuatia was alienated and fragmented. These questions are addressed through a bespoke method that was developed to link data from several sources. These include (but are not limited to) historic records of land alienation, held by the Māori Land Court, and geospatial information available through Land Information New Zealand.
The key findings show that approximately 94% of the original Opuatia has been alienated, with only small parcles of land remaining in Ngāti Tiipa ownership. The late 1890s and early 1900s were a criticial period where over 80% of alienations were carried out. The results inidcate that the Crown was a key driver of this process, directly alienating more than 18,000 acres from Opuatia, much of which was taken on a single day in 1896. Individual settlers were responsible for most other alienations, and some of the same names appear several times in the historical record as settler families alienated clusters of land to build up significant stakes in the area. Finally, another result of this report is the method itself, which outlines an approach for tracing a defined block of land through the Native Land Court and linking this information to geospatial datasets.
The limitations of this report include the poor interoperability of key data sources, and the barriers that this presents to other hapū or organisations who may want to replicate this work. A more detailed investigation of archival records is required to examine the specific reasons behind why each parent block, and the subdivisions with them, was alienated from Ngāti Tiipa ownership.

text: The alienation of the Opuatia block: A GIS case study report written for Counting our Tūpuna This report provides an analysis and visualisation of the fragmentation and alienation of the Opuatia block (Opuatia hereafter), as well as changes in its ownership and geographic structure since 1866.
The three main aims are to quantify the amount of Opuatia remaining in Ngāti Tiipa ownership at the end of each decade, identifying critical moments in time, and highlighting the processes through which Opuatia was alienated and fragmented. These questions are addressed through a bespoke method that was developed to link data from several sources. These include (but are not limited to) historic records of land alienation, held by the Māori Land Court, and geospatial information available through Land Information New Zealand.
The key findings show that approximately 94% of the original Opuatia has been alienated, with only small parcles of land remaining in Ngāti Tiipa ownership. The late 1890s and early 1900s were a criticial period where over 80% of alienations were carried out. The results inidcate that the Crown was a key driver of this process, directly alienating more than 18,000 acres from Opuatia, much of which was taken on a single day in 1896. Individual settlers were responsible for most other alienations, and some of the same names appear several times in the historical record as settler families alienated clusters of land to build up significant stakes in the area. Finally, another result of this report is the method itself, which outlines an approach for tracing a defined block of land through the Native Land Court and linking this information to geospatial datasets.
The limitations of this report include the poor interoperability of key data sources, and the barriers that this presents to other hapū or organisations who may want to replicate this work. A more detailed investigation of archival records is required to examine the specific reasons behind why each parent block, and the subdivisions with them, was alienated from Ngāti Tiipa ownership.

year: 2021