title: The use of cellulose in bio-derived formulations for 3D/4D printing: A review

authors: Gauss, Christian

abstract: Cellulose is one of the most versatile biopolymers found in nature. Its use is now transitioning from sustainability-focused development to provide technical solutions across a wide range of applications. This review paper describes the use of cellulose as reinforcement in biocomposites and recent related advances in 3D printing technologies, including 4D (responsive/smart) printing and current/future applications. Relevant aspects such as the origin and intrinsic/structural properties of cellulose and cellulose/matrix interaction during processing are discussed. A particular focus is directed to identify opportunities for the development of new cellulose-based composites, formulation requirements for 3D/4D printing, and comprehension of the interplay between rheology, chemistry, and processing. Overall, new materials and technologies based on cellulose have shown promising results for real-life applications, opening new scientific development opportunities and a new generation of sustainable and advanced materials.

text: The use of cellulose in bio-derived formulations for 3D/4D printing: A review Cellulose is one of the most versatile biopolymers found in nature. Its use is now transitioning from sustainability-focused development to provide technical solutions across a wide range of applications. This review paper describes the use of cellulose as reinforcement in biocomposites and recent related advances in 3D printing technologies, including 4D (responsive/smart) printing and current/future applications. Relevant aspects such as the origin and intrinsic/structural properties of cellulose and cellulose/matrix interaction during processing are discussed. A particular focus is directed to identify opportunities for the development of new cellulose-based composites, formulation requirements for 3D/4D printing, and comprehension of the interplay between rheology, chemistry, and processing. Overall, new materials and technologies based on cellulose have shown promising results for real-life applications, opening new scientific development opportunities and a new generation of sustainable and advanced materials.

year: 2021

title: Geology of the western Mamaku Plateau and variations in the Mamaku ignimbrite

authors: Fransen, Pieter J.B.

subjects: Geology

abstract: Pleistocene ignimbrites in the western Mamaku Plateau east of Putaruru consist of the following successively younger formations: (?) Ongatiti Ignimbrite, Ahuroa Ignimbrite, Whakamaru Ignimbrite, Waihou Ignimbrite (new), Waimakariri Ignimbrite (new), Mamaku Ignimbrite. They can be distinguished on the basis of their compositional-, welding-, textural-, and field characteristics. The ignimbrites are separated by unconformities, and intercalated fluvial sedimentary deposits. The three most important units are the Whakamaru, Waimakariri and Mamaku Ignimbrites, which are well exposed and widespread.

The Mamaku Ignimbrite covers a surface area of nearly 4300 km² on the Mamaku Plateau. Corresponding vertical changes in lithology, petrography and physical properties near the Rotorua Caldera define two flow members: a lower Sheet 1, and an upper Sheet 2, each of which is about 60 m thick. The ignimbrite constitutes a simple cooling unit which indicates that Sheet 2 was emplaced shortly after Sheet 1. Only one sheet (? Sheet 1) is evident in the western Mamaku Plateau. Welding zonation near-to-source is characterised by a gradual change from a basal glassy lenticulite zone to a nonwelded top. Smith's (1960b) zonal classification ranks the ignimbrite as being partially welded. This condition suggests that total thickness is not necessarily a major factor in the degree of welding of ignimbrites. 

The phenocryst assemblage of plagioclase, quartz, pyroxene, opaques, hornblende and biotite, is set in a devitrified fine ash matrix, which is an ubiquitous feature of the ignimbrite. Higher modal phenocryst content at the base of each sheet is attributed to compaction. Overall the phenocrysts are uniformly distributed and there is little vertical variation. Seven bulk chemical analyses reveal only minor vertical variations in composition. The near uniform chemical and mineralogical trends suggest nondifferentiation of the source magma. 

Texturally the Mamaku Ignimbrite is a poorly sorted lapilli ash. The grading of fragments like that shown in "the standard ignimbrite flow unit" is absent. However, the presence of a zone of aligned pumice fragments indicates that laminar flow operated during the later stages of deposition. Two major inferred faults in the western Mamaku Plateau define a western horst, a central graben, and an eastern horst. The eastern horst is postulated to be the southern extension of the axial median horst in the Hauraki Depression and of the Hauraki Rift. 

Repeated and extended intervals of erosion followed the emplacement of the ignimbrites. Detritus from the eroding sheets was removed by rivers flowing into the Hauraki Depression. Construction of the Mamaku Plateau has largely taken place since the eruption of the Whakamaru Ignimbrite, c.300,000 years ago, and terminated with the eruption of the Mamaku Ignimbrite, c.l40,000 years ago. Excavation of the long deep valleys in the plateau occurred mainly in the latter 42,000 years.

text: Geology of the western Mamaku Plateau and variations in the Mamaku ignimbrite Pleistocene ignimbrites in the western Mamaku Plateau east of Putaruru consist of the following successively younger formations: (?) Ongatiti Ignimbrite, Ahuroa Ignimbrite, Whakamaru Ignimbrite, Waihou Ignimbrite (new), Waimakariri Ignimbrite (new), Mamaku Ignimbrite. They can be distinguished on the basis of their compositional-, welding-, textural-, and field characteristics. The ignimbrites are separated by unconformities, and intercalated fluvial sedimentary deposits. The three most important units are the Whakamaru, Waimakariri and Mamaku Ignimbrites, which are well exposed and widespread.

The Mamaku Ignimbrite covers a surface area of nearly 4300 km² on the Mamaku Plateau. Corresponding vertical changes in lithology, petrography and physical properties near the Rotorua Caldera define two flow members: a lower Sheet 1, and an upper Sheet 2, each of which is about 60 m thick. The ignimbrite constitutes a simple cooling unit which indicates that Sheet 2 was emplaced shortly after Sheet 1. Only one sheet (? Sheet 1) is evident in the western Mamaku Plateau. Welding zonation near-to-source is characterised by a gradual change from a basal glassy lenticulite zone to a nonwelded top. Smith's (1960b) zonal classification ranks the ignimbrite as being partially welded. This condition suggests that total thickness is not necessarily a major factor in the degree of welding of ignimbrites. 

The phenocryst assemblage of plagioclase, quartz, pyroxene, opaques, hornblende and biotite, is set in a devitrified fine ash matrix, which is an ubiquitous feature of the ignimbrite. Higher modal phenocryst content at the base of each sheet is attributed to compaction. Overall the phenocrysts are uniformly distributed and there is little vertical variation. Seven bulk chemical analyses reveal only minor vertical variations in composition. The near uniform chemical and mineralogical trends suggest nondifferentiation of the source magma. 

Texturally the Mamaku Ignimbrite is a poorly sorted lapilli ash. The grading of fragments like that shown in "the standard ignimbrite flow unit" is absent. However, the presence of a zone of aligned pumice fragments indicates that laminar flow operated during the later stages of deposition. Two major inferred faults in the western Mamaku Plateau define a western horst, a central graben, and an eastern horst. The eastern horst is postulated to be the southern extension of the axial median horst in the Hauraki Depression and of the Hauraki Rift. 

Repeated and extended intervals of erosion followed the emplacement of the ignimbrites. Detritus from the eroding sheets was removed by rivers flowing into the Hauraki Depression. Construction of the Mamaku Plateau has largely taken place since the eruption of the Whakamaru Ignimbrite, c.300,000 years ago, and terminated with the eruption of the Mamaku Ignimbrite, c.l40,000 years ago. Excavation of the long deep valleys in the plateau occurred mainly in the latter 42,000 years.

year: 1982

title: Strategic framing: indigenous culture, identity, and politics

authors: Schoenberger-Orgad, Michèle Anne

subjects: New Zealand

abstract: This article analyses the role played by culture and the strategic communication of culture in the formation and establishment of the Māori Party. As an indigenous grassroots party, which achieved electoral success in the 2005, general election in New Zealand, the Māori Party offers an unusual case of cultural primacy as a political party for indigenous people. The Māori Party campaigned to be the first successful party to give a distinctive voice to Māori in a parliament dominated by Pakeha (New Zealand Europeans).

In examining the Māori Party's formation and campaign as a case study, the article focuses on socio-political conditions, issues of national identity, media changes, and the cultural relations between Māori and Pakeha. It pays particular attention to those that influenced public opinion during the 14 months of election campaigning. It argues that the strategic framing of the Māori Party as a movement giving a distinctive voice for Māori established the foundations for the campaign's success. In conclusion, the significance of the achievements of the Māori Party in the 2008 general election are discussed as evidence of the now distinct and recognized representation of Māori within the New Zealand democratic process.

text: Strategic framing: indigenous culture, identity, and politics This article analyses the role played by culture and the strategic communication of culture in the formation and establishment of the Māori Party. As an indigenous grassroots party, which achieved electoral success in the 2005, general election in New Zealand, the Māori Party offers an unusual case of cultural primacy as a political party for indigenous people. The Māori Party campaigned to be the first successful party to give a distinctive voice to Māori in a parliament dominated by Pakeha (New Zealand Europeans).

In examining the Māori Party's formation and campaign as a case study, the article focuses on socio-political conditions, issues of national identity, media changes, and the cultural relations between Māori and Pakeha. It pays particular attention to those that influenced public opinion during the 14 months of election campaigning. It argues that the strategic framing of the Māori Party as a movement giving a distinctive voice for Māori established the foundations for the campaign's success. In conclusion, the significance of the achievements of the Māori Party in the 2008 general election are discussed as evidence of the now distinct and recognized representation of Māori within the New Zealand democratic process.

year: 2011