title: Two complexes containing 19-atom chains linking metal centres

authors: Bruce, Michael I.

subjects: carbon chain

abstract: The first example of a complex containing a C₁₉ chain, {Co₃(μ-dppm)(CO)₇}{μ₃-C(C≡C)₉}{W(CO)₃Cp}, has been prepared in 22% yield from the Pd(0) / Cu(I)-catalysed reaction between I(C≡C)₃I, W{C≡CC≡CAu(PPh₃)}(CO)₃Cp and Co₃{μ₃-C(C≡C)₄Au(PPh₃)}(μ-dppm)(CO)₇. Other products also formed include {Co₃(μ-dppm)(CO)₇}{μ₃-C(C≡C)₆}{W(CO)₃Cp} (32%), {Co₃(μ-dppm)(CO)₇}₂{μ₃:μ₃-C(C≡C)xC} [x = 8 (6%) and 11 (5%)], containing respectively C₁₃, C₁₈ and C₂₄ chains, and {W(CO)₃Cp}₂{μ-(C≡C)x} (x = 4, 7) (traces). A second example of a 19-atom chain is found in Hg{(C≡C)₄C[Co₃(μ-dppm)(CO)₇]}₂, obtained in 24% yield from the reaction between Hg(OAc)₂ and Co₃{μ₃-C(C≡C)₄SiMe₃}(μ-dppm)(CO)₇ in the presence of NaOMe.

text: Two complexes containing 19-atom chains linking metal centres The first example of a complex containing a C₁₉ chain, {Co₃(μ-dppm)(CO)₇}{μ₃-C(C≡C)₉}{W(CO)₃Cp}, has been prepared in 22% yield from the Pd(0) / Cu(I)-catalysed reaction between I(C≡C)₃I, W{C≡CC≡CAu(PPh₃)}(CO)₃Cp and Co₃{μ₃-C(C≡C)₄Au(PPh₃)}(μ-dppm)(CO)₇. Other products also formed include {Co₃(μ-dppm)(CO)₇}{μ₃-C(C≡C)₆}{W(CO)₃Cp} (32%), {Co₃(μ-dppm)(CO)₇}₂{μ₃:μ₃-C(C≡C)xC} [x = 8 (6%) and 11 (5%)], containing respectively C₁₃, C₁₈ and C₂₄ chains, and {W(CO)₃Cp}₂{μ-(C≡C)x} (x = 4, 7) (traces). A second example of a 19-atom chain is found in Hg{(C≡C)₄C[Co₃(μ-dppm)(CO)₇]}₂, obtained in 24% yield from the reaction between Hg(OAc)₂ and Co₃{μ₃-C(C≡C)₄SiMe₃}(μ-dppm)(CO)₇ in the presence of NaOMe.

year: 2009

title: Flexibility Analysis of Heat Exchanger Network Retrofit Designs using Monte Carlo Simulation

authors: Lal, Nathan S.

abstract: The aim of this paper is to use Monte Carlo Simulation (MCS) to conduct an analysis of the flexibility and controllability of retrofitted Heat Exchanger Network (HEN) designs. Historical plant data is often uncertain and variable but is an important tool for understanding the real-time operation of a HEN. MCS uses these uncertainties to give an analysis of the retrofitted HENs, and it can be used in a more detailed analysis of the controllability and flexibility. Using Monte Carlo Simulation, inflexibility has been defined as the probability of a HEN to fail to meet temperature targets within defined tolerances. Inflexibility can be used as a tool to guide the retrofit analysis of a HEN. A retrofit HEN design should improve the flexibility of the network without compromising on the expected energy savings. The proposed method is demonstrated using a four-stream HEN problem. The inflexibility of the network was shown to be improved with bypass control and optimal allocation of retrofit area and the proposed method succeeds in augmenting the retrofit design method so that cost-effective, flexible retrofit HENs can be identified.

text: Flexibility Analysis of Heat Exchanger Network Retrofit Designs using Monte Carlo Simulation The aim of this paper is to use Monte Carlo Simulation (MCS) to conduct an analysis of the flexibility and controllability of retrofitted Heat Exchanger Network (HEN) designs. Historical plant data is often uncertain and variable but is an important tool for understanding the real-time operation of a HEN. MCS uses these uncertainties to give an analysis of the retrofitted HENs, and it can be used in a more detailed analysis of the controllability and flexibility. Using Monte Carlo Simulation, inflexibility has been defined as the probability of a HEN to fail to meet temperature targets within defined tolerances. Inflexibility can be used as a tool to guide the retrofit analysis of a HEN. A retrofit HEN design should improve the flexibility of the network without compromising on the expected energy savings. The proposed method is demonstrated using a four-stream HEN problem. The inflexibility of the network was shown to be improved with bypass control and optimal allocation of retrofit area and the proposed method succeeds in augmenting the retrofit design method so that cost-effective, flexible retrofit HENs can be identified.

year: 2019

title: Ue Waerea

authors: Tuaupiki, Jackie Whetumarama

subjects: Waerea

abstract: Mai i Mōkau ki Tāmaki, Mangatoatoa, Pare-Waikato, Pare-Hauraki, Te Kaokaoroa o Pātetere, ko te whakapono, nā Tāwhaki i piki te poutama ki te tāhuhu matapu, ka riro mai i a ia ngā kete o te wānanga. E kīngia ai, ko te pūtake tērā o te mātauranga Māori. Hei tā Wiri (2001), nā te mātauranga Māori, ko te mātauranga Māori ā-waha. Nāna, ko te waiata. Nā te waiata, ko te karakia. Kei raro i te karakia, ko te takere kaupapa tēnei, ko te waerea. Ko te whāinga o tēnei tuhituhinga, he rangahau i ngā pūtake o te waerea me te āta titiro ki ngā kaupapa kei a ia me tōna kawe i roto i aua kaupapa i ngā wā o mua, ā, nō nāianei hoki. Ko te waerea te pane o ngā karakia Māori ki roto o Tainui, otirā, ki roto i ngētehi o ngā whakaritenga, ā, ka tirohia ngēnei whakaritenga e rere ai te waerea, pēnei i te tomo whare, i te tomo urupā, i te takahi whare, i te whakamānu waka me te maha o ngā mahi a te ao Māori ki roto o Tainui.

text: Ue Waerea Mai i Mōkau ki Tāmaki, Mangatoatoa, Pare-Waikato, Pare-Hauraki, Te Kaokaoroa o Pātetere, ko te whakapono, nā Tāwhaki i piki te poutama ki te tāhuhu matapu, ka riro mai i a ia ngā kete o te wānanga. E kīngia ai, ko te pūtake tērā o te mātauranga Māori. Hei tā Wiri (2001), nā te mātauranga Māori, ko te mātauranga Māori ā-waha. Nāna, ko te waiata. Nā te waiata, ko te karakia. Kei raro i te karakia, ko te takere kaupapa tēnei, ko te waerea. Ko te whāinga o tēnei tuhituhinga, he rangahau i ngā pūtake o te waerea me te āta titiro ki ngā kaupapa kei a ia me tōna kawe i roto i aua kaupapa i ngā wā o mua, ā, nō nāianei hoki. Ko te waerea te pane o ngā karakia Māori ki roto o Tainui, otirā, ki roto i ngētehi o ngā whakaritenga, ā, ka tirohia ngēnei whakaritenga e rere ai te waerea, pēnei i te tomo whare, i te tomo urupā, i te takahi whare, i te whakamānu waka me te maha o ngā mahi a te ao Māori ki roto o Tainui.

year: 2011-04