title: (Chloromethyl)pentacarbonylmanganese(I): a crystal structure with a non-crystallographic centre of symmetry

authors: Nicholson, Brian K.

subjects: chloromethyl

abstract: There are two molecules in the asymmetric unit of the P2₁/c unit cell of ClCH₂Mn(CO)₅, the first halomethyl complex of manganese to be structurally determined. The molecules are crystallographically independent, despite an apparent local centre of symmetry. The average bond parameters include Mn–Calkyl 2.128(8) Å, C–Cl 1.811(8) Å and Mn–C–Cl 116.4(4)°

text: (Chloromethyl)pentacarbonylmanganese(I): a crystal structure with a non-crystallographic centre of symmetry There are two molecules in the asymmetric unit of the P2₁/c unit cell of ClCH₂Mn(CO)₅, the first halomethyl complex of manganese to be structurally determined. The molecules are crystallographically independent, despite an apparent local centre of symmetry. The average bond parameters include Mn–Calkyl 2.128(8) Å, C–Cl 1.811(8) Å and Mn–C–Cl 116.4(4)°

year: 2008

title: Current singularities at Quasi-separatrix layers and three-dimensional magnetic nulls

authors: Craig, Ian J.D.

subjects: Science & Technology

abstract: The open problem of how singular current structures form in line-tied, three-dimensional magnetic fields is addressed. A Lagrangian magneto-frictional relaxation method is employed to model the field evolution toward the final near-singular state. Our starting point is an exact force-free solution of the governing magnetohydrodynamic equations that is sufficiently general to allow for topological features like magnetic nulls to be inside or outside the computational domain, depending on a simple set of parameters. Quasi-separatrix layers (QSLs) are present in these structures and, together with the magnetic nulls, they significantly influence the accumulation of current. It is shown that perturbations affecting the lateral boundaries of the configuration lead not only to collapse around the magnetic null but also to significant QSL currents. Our results show that once a magnetic null is present, the developing currents are always attracted to that specific location and show a much stronger scaling with resolution than the currents that form along the QSL. In particular, the null-point scalings can be consistent with models of "fast" reconnection. The QSL currents also appear to be unbounded but give rise to weaker singularities, independent of the perturbation amplitude.

text: Current singularities at Quasi-separatrix layers and three-dimensional magnetic nulls The open problem of how singular current structures form in line-tied, three-dimensional magnetic fields is addressed. A Lagrangian magneto-frictional relaxation method is employed to model the field evolution toward the final near-singular state. Our starting point is an exact force-free solution of the governing magnetohydrodynamic equations that is sufficiently general to allow for topological features like magnetic nulls to be inside or outside the computational domain, depending on a simple set of parameters. Quasi-separatrix layers (QSLs) are present in these structures and, together with the magnetic nulls, they significantly influence the accumulation of current. It is shown that perturbations affecting the lateral boundaries of the configuration lead not only to collapse around the magnetic null but also to significant QSL currents. Our results show that once a magnetic null is present, the developing currents are always attracted to that specific location and show a much stronger scaling with resolution than the currents that form along the QSL. In particular, the null-point scalings can be consistent with models of "fast" reconnection. The QSL currents also appear to be unbounded but give rise to weaker singularities, independent of the perturbation amplitude.

year: 2014-11-10

title: Ngā mahi: Kaupapa Māori outcomes and indicators kete

authors: Jefferies, Richard

subjects: New Zealand

abstract: As part of the Planning Under Cooperative Mandates research (PUCM) we developed a kaupapa Māori outcomes and indicators framework. This framework reflects tikanga Māori and Māori values. It also considers issues (including environmental issues) according to those tikanga that particular issues invoke. For example, tikanga brought into play in relation to council treatment and disposal of sewerage include tapu (sacred), and might also impact on the mauri (life-force) of water if treated effluent were to enter waterways.

The intention of our research has been to clarify and define key Māori environmental concepts so that stakeholders (including council staff) will have a terms of reference against which they can compare desired environmental outcomes from different perspectives and be better placed to integrate Māori environmental outcomes into planning processes. The end-point is this Nga Mahi kete report containing tikanga-based worksheets and the guidelines for using them.

text: Ngā mahi: Kaupapa Māori outcomes and indicators kete As part of the Planning Under Cooperative Mandates research (PUCM) we developed a kaupapa Māori outcomes and indicators framework. This framework reflects tikanga Māori and Māori values. It also considers issues (including environmental issues) according to those tikanga that particular issues invoke. For example, tikanga brought into play in relation to council treatment and disposal of sewerage include tapu (sacred), and might also impact on the mauri (life-force) of water if treated effluent were to enter waterways.

The intention of our research has been to clarify and define key Māori environmental concepts so that stakeholders (including council staff) will have a terms of reference against which they can compare desired environmental outcomes from different perspectives and be better placed to integrate Māori environmental outcomes into planning processes. The end-point is this Nga Mahi kete report containing tikanga-based worksheets and the guidelines for using them.

year: 2009-06-30