title: Synthesis and X-ray structures of triphenylphosphine-mercury(II) thiosalicylate complexes: novel aggregation processes

authors: Nicholson, Brian K.

subjects: Mercury

abstract: Reaction of [HgCl2(PPh3)2] with one equivalent of thiosalicylic acid (tsalH2, HSC6H4CO2H) and excess triethylamine, followed by recrystallisation from dichloromethane-diethyl ether gives the compound [Hg2(tsal)2(PPh3)2] (2). This has a bis(S,O)-chelated mercury centre with a nido-trigonal bipyramidal coodination, with the four oxygens of the two carboxylates also coordinated to a Hg(PPh3)2 moiety. When a reduced quantity of pyridine was used as the base a different crystalline product was isolated. This was characterised as [Hg2(tsal)2(PPh3)2][Hg(tsalH)2] (3), which contains the same [Hg2(tsal)2(PPh3)2] moiety found for 2, co-crystallised with a [Hg(tsalH)2]. The two mercury-thiosalicylate species are connected by means of O-H O hydrogen bonding.

text: Synthesis and X-ray structures of triphenylphosphine-mercury(II) thiosalicylate complexes: novel aggregation processes Reaction of [HgCl2(PPh3)2] with one equivalent of thiosalicylic acid (tsalH2, HSC6H4CO2H) and excess triethylamine, followed by recrystallisation from dichloromethane-diethyl ether gives the compound [Hg2(tsal)2(PPh3)2] (2). This has a bis(S,O)-chelated mercury centre with a nido-trigonal bipyramidal coodination, with the four oxygens of the two carboxylates also coordinated to a Hg(PPh3)2 moiety. When a reduced quantity of pyridine was used as the base a different crystalline product was isolated. This was characterised as [Hg2(tsal)2(PPh3)2][Hg(tsalH)2] (3), which contains the same [Hg2(tsal)2(PPh3)2] moiety found for 2, co-crystallised with a [Hg(tsalH)2]. The two mercury-thiosalicylate species are connected by means of O-H O hydrogen bonding.

year: 2002-06-01

title: Hybrid-heating-systems for optimized integration of low-temperature-heat and renewable energy

authors: Schumm, Gregor M.

abstract: The food and beverage industries are significant industrial producers of green-house gas (GHG) emissions. Reductions can be achieved by increased energy efficiency and the use of renewable energy to replace fossil fuel use. The main efficiency method within this industries is the use of low temperature heat (LTH), i.e. below 100 °C. Sources for LTH include heat recovery from process flows, heat rejection from utility operations (i.e. chillers, combined heat and power (CHP), condensing economisers), and renewable energy (i.e. solar thermal). A hybrid heating system (H2S) has been developed that can retrofit steam heater designs for the integration of LTH. Two different systems have been found, for adapting direct and indirect steam heaters, either installing an extra hot water heater or using the indirect hot water loop for the integration. In both systems the existing steam heater remains a part of the system for individual back-up. The set-up and the control algorithm of the H₂S allow installing a 37 % smaller hot water grid than a common design with one central back-up heater. Investigations using a comprehensive model of a whey separation and drying plant showed that implementing a piston engine CHP unit combined with the H₂S reduce the energy costs by 42 % and the GHG emissions by 33 %.

text: Hybrid-heating-systems for optimized integration of low-temperature-heat and renewable energy The food and beverage industries are significant industrial producers of green-house gas (GHG) emissions. Reductions can be achieved by increased energy efficiency and the use of renewable energy to replace fossil fuel use. The main efficiency method within this industries is the use of low temperature heat (LTH), i.e. below 100 °C. Sources for LTH include heat recovery from process flows, heat rejection from utility operations (i.e. chillers, combined heat and power (CHP), condensing economisers), and renewable energy (i.e. solar thermal). A hybrid heating system (H2S) has been developed that can retrofit steam heater designs for the integration of LTH. Two different systems have been found, for adapting direct and indirect steam heaters, either installing an extra hot water heater or using the indirect hot water loop for the integration. In both systems the existing steam heater remains a part of the system for individual back-up. The set-up and the control algorithm of the H₂S allow installing a 37 % smaller hot water grid than a common design with one central back-up heater. Investigations using a comprehensive model of a whey separation and drying plant showed that implementing a piston engine CHP unit combined with the H₂S reduce the energy costs by 42 % and the GHG emissions by 33 %.

year: 2016

title: Transitioning from kōhanga reo to kura

authors: Hohepa, Margie Kahukura

abstract: This is a collaborative cross-sector research project involving a kōhanga reo (Māori immersion early childhood language nest) kura (Māori language immersion school) and university-based researchers. It focuses on tamariki (children) moving from kōhanga reo to kura classrooms and will examine the development of an 'akoranga whakawhiti', a transition programme that will be based at Te Kōhanga Reo o Ngā Kuaka in Hamilton. The over arching research question for this project is: Pēhea rā te āhuatanga me te kounga o ngā whakawhitinga mai i te kōhanga ki te kura mō ngā tamariki, whānau, kaiako me te hāpori? - What do effective transitions from kōhanga reo to kura look like, feel like, and sound like, for tamariki, whānau, kaiako and the community? The project aims to provide important new insights into learning and teaching in Māori-medium settings and into ways of enhancing transitions from Maori-medium early childhood education to Māori medium classrooms.

text: Transitioning from kōhanga reo to kura This is a collaborative cross-sector research project involving a kōhanga reo (Māori immersion early childhood language nest) kura (Māori language immersion school) and university-based researchers. It focuses on tamariki (children) moving from kōhanga reo to kura classrooms and will examine the development of an 'akoranga whakawhiti', a transition programme that will be based at Te Kōhanga Reo o Ngā Kuaka in Hamilton. The over arching research question for this project is: Pēhea rā te āhuatanga me te kounga o ngā whakawhitinga mai i te kōhanga ki te kura mō ngā tamariki, whānau, kaiako me te hāpori? - What do effective transitions from kōhanga reo to kura look like, feel like, and sound like, for tamariki, whānau, kaiako and the community? The project aims to provide important new insights into learning and teaching in Māori-medium settings and into ways of enhancing transitions from Maori-medium early childhood education to Māori medium classrooms.

year: 2014