title: Development and design of binder systems for titanium metal injection molding: An overview

authors: Wen, Guian

subjects: titanium metal injection molding

abstract: Titanium metal injection molding (Ti-MIM) has been practiced since the late 1980s. Logically, the Ti-MIM practice follows the similar processes developed for the antecedent materials such as stainless steel and ceramics. Although Ti-MIM is a favorite research topic today, the issue of convincing the designers to use Ti injection-molded parts still exists. This is mainly because of the concern about contamination which seems unavoidable during the Ti-MIM process. Much information about the binder formulation, powder requirements, debinding, and sintering is available in the literature. There are several powder vendors and feedstock suppliers. However, most of the binders in the feedstock are proprietarily protected. The disclosed information on the binders used for formulating powder feedstock is very limited, which in turn discourages their adoption by engineering designers. This overview intends to discuss some of major binder systems for Ti-MIM available in the literature. It serves to provide a guideline for the Ti-MIM practitioners to choose a suitable powder feedstock.

text: Development and design of binder systems for titanium metal injection molding: An overview Titanium metal injection molding (Ti-MIM) has been practiced since the late 1980s. Logically, the Ti-MIM practice follows the similar processes developed for the antecedent materials such as stainless steel and ceramics. Although Ti-MIM is a favorite research topic today, the issue of convincing the designers to use Ti injection-molded parts still exists. This is mainly because of the concern about contamination which seems unavoidable during the Ti-MIM process. Much information about the binder formulation, powder requirements, debinding, and sintering is available in the literature. There are several powder vendors and feedstock suppliers. However, most of the binders in the feedstock are proprietarily protected. The disclosed information on the binders used for formulating powder feedstock is very limited, which in turn discourages their adoption by engineering designers. This overview intends to discuss some of major binder systems for Ti-MIM available in the literature. It serves to provide a guideline for the Ti-MIM practitioners to choose a suitable powder feedstock.

year: 2013

title: Tree-climbing capabilities of Norway and ship rats

authors: Foster, Stacey Patricia

subjects: invasive rats

abstract: Norway and ship rats (Rattus norvegicus and Rattus rattus) have invaded many habitats of conservation value worldwide, but Norway rats are widely assumed to be less of a threat to tree-nesting biota than are ship rats because they are less adept at climbing. We tested this assumption by measuring the capabilities of wild-caught captive rats of both species in reaching food rewards above ground, placed at fixed sites of increasingly difficult access. We confirmed that Norway rats were much slower and less agile than ship rats, but could in fact, given enough time, reach the same height above ground, run across the same thin ropes fixed at both ends and climb a real tree. However, they were more easily defeated by obstacles, more dependent on the availability of footholds, more vulnerable to falls, and those of >200 g body weight were significantly less likely to reach food rewards at the unsupported ends of small branches. We conclude that Norway rats seldom forage above ground, not because they cannot climb but because arboreal foraging is more risky and less likely to be rewarding for them.

text: Tree-climbing capabilities of Norway and ship rats Norway and ship rats (Rattus norvegicus and Rattus rattus) have invaded many habitats of conservation value worldwide, but Norway rats are widely assumed to be less of a threat to tree-nesting biota than are ship rats because they are less adept at climbing. We tested this assumption by measuring the capabilities of wild-caught captive rats of both species in reaching food rewards above ground, placed at fixed sites of increasingly difficult access. We confirmed that Norway rats were much slower and less agile than ship rats, but could in fact, given enough time, reach the same height above ground, run across the same thin ropes fixed at both ends and climb a real tree. However, they were more easily defeated by obstacles, more dependent on the availability of footholds, more vulnerable to falls, and those of >200 g body weight were significantly less likely to reach food rewards at the unsupported ends of small branches. We conclude that Norway rats seldom forage above ground, not because they cannot climb but because arboreal foraging is more risky and less likely to be rewarding for them.

year: 2011

title: Identifying fisheries regions in New Zealand: Some conceptual difficulties

authors: Rennie, Hamish Gordon

subjects: Fisheries

abstract: The importance of fisheries to nations is reflected in the production and employment statistics of the country. It is also reflected in socio-cultural symbols (for instance songs, tales), and in socio-political hegemonies.  Just as these may vary from one nation to another, they may also vary from region to region within a nation.  Several nations speak openly in terms of 'fisheries regions' and there have been a number of attempts to identify such regions in the social science literature. An understanding of these regions is seen as step towards defining appropriate policies for the sustainable management of their resources.

In 1986, New Zealand established an innovative fishery management system based on individually transferable quota (ITQ), and subsequently removed the (never-implemented) region-based, fishery management planning structure from the statutes.  These changes might be indicative of a loss of geography, a flattening of the nation's "fishing topography", and might be expected to result in significant changes to the nature and location of fisheries regions.

This paper outlines the changes in the management structure of New Zealand's fisheries. We then attempt a preliminary analysis of fisheries regions in New Zealand as the basis for a "new regional" geography of New Zealand's fisheries. In the process we discuss various criteria for defining fishery regions and present our initial categorisation of New Zealand into those regions. The relationship between these regions and related institutional structures is then discussed. This raises a number of additional questions regarding the concept of a fisheries region, especially in the context of a resurgent indigenous (Maaori) culture, the emergence of new fishing peoples in New Zealand, and the respective size of recreational and commercial fishing sectors.

text: Identifying fisheries regions in New Zealand: Some conceptual difficulties The importance of fisheries to nations is reflected in the production and employment statistics of the country. It is also reflected in socio-cultural symbols (for instance songs, tales), and in socio-political hegemonies.  Just as these may vary from one nation to another, they may also vary from region to region within a nation.  Several nations speak openly in terms of 'fisheries regions' and there have been a number of attempts to identify such regions in the social science literature. An understanding of these regions is seen as step towards defining appropriate policies for the sustainable management of their resources.

In 1986, New Zealand established an innovative fishery management system based on individually transferable quota (ITQ), and subsequently removed the (never-implemented) region-based, fishery management planning structure from the statutes.  These changes might be indicative of a loss of geography, a flattening of the nation's "fishing topography", and might be expected to result in significant changes to the nature and location of fisheries regions.

This paper outlines the changes in the management structure of New Zealand's fisheries. We then attempt a preliminary analysis of fisheries regions in New Zealand as the basis for a "new regional" geography of New Zealand's fisheries. In the process we discuss various criteria for defining fishery regions and present our initial categorisation of New Zealand into those regions. The relationship between these regions and related institutional structures is then discussed. This raises a number of additional questions regarding the concept of a fisheries region, especially in the context of a resurgent indigenous (Maaori) culture, the emergence of new fishing peoples in New Zealand, and the respective size of recreational and commercial fishing sectors.

year: 1998-06-01