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1.

Intention, Goal, Scope, Background

A new paradigm called System-In-a-Package (SIP) is expected to represent the wave of future microsystem packaging and integration. No environmental assessment has been made of manufacturing processes for SIP and the purpose of this paper is to assess the upstream environmental impact of the process used by Chalmers to manufacture an electronic product using the SIP technology.

Objectives

This paper aims at an environmental assessment of a gallium arsenide (GaAs) Monolithic Microwave Integrated Circuit (MMIC) Switch Product based on a so-called SIP concept on a Liquid Crystalline Polymer (LCP) substrate. This study focuses on the identification of environmentally substantial upstream processes from cradle-to-gate for this product.

Methods

This work is based on a life cycle inventory model that has been developed earlier by the authors, and this model is now applied to the system including the straight-line manufacturing processes in the facilities of the Microtechnology Centre (MC2) at Chalmers University of Technology and the manufacturing processes of raw materials in the upstream processes. A main scenario was built in the LCA software EcoLab corresponding to the linear process in MC2 and other manufacturing processes were identified in the upstream which were used to develop the upstream process tree.

Results and Discussion

The spin coating of photoresistant material has the highest environmental impact within the system boundaries and the uncertainty of the results is estimated to be small. The exposure and development as well as deposition stages also give impacts, both for the copper and resistant material deposition. In the manufacturing processes inside MC2, the electricity consumption clearly dominates. The results predominantly reflect energy use, whereas toxicological aspects could not be reliably assessed due to lack of data and reliable methods, and therefore needs separate attention. Nevertheless, a toxicology assessment has been made with the Toxic Potential Indicator (TPI), which, compared to a telephone, showed a relatively large value for the switch. The toxic potential of the switch is higher per mass unit than a digital telephone.

Conclusions

The previously developed LCA data collection model worked well for the SIP product. The electricity consumption for the deposition machine and the solvent consumption in spin coating are the two most important hot spots. For greenhouse warming potential the acetone consumption in the spin coating steps is the most significant contributor, and the copper consumption in the copper deposition step dominates for abiotic resource depletion.

Recommendations and Outlook

It is recommended that the machines in the MC2 process lab used to manufacture the SIP product are studied for a longer period of time as it would make the electricity consumption figures more accurate. More electronic packaging concepts, such as System-on-a-chip (SOC) and multichip modules (MCM), should be evaluated and compared to SIP.
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Intention and Background.  

This paper outlines guidelines for the treatment of energy in LCAs of forest products. The paper is a result of the Cost Action E 9 ‘Life cycle assessment of forestry and forest products’ and reflects the experience of Cost E9 delegates, contributing to Working Group ‘End of life — recycling, disposal and energy generation’.  相似文献   

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This article is a summary of my dissertation in which LCA was applied to food products and production systems. The overall objectives were: (1) to learn more about the feasibility and limitations of LCAs of systems for the production and consumption of foods (food systems); and (2) to generate information on the environmental impact of such systems. Case studies of tomato ketchup and white bread were carried out. The main conclusion is that LCA is very valuable for incorporating environmental aspects in the development of more sustainable food systems. One of the major problems encountered was the great scarcity of environmental data. It was found that there is a need for simplified methods that can be used as a compass to show the direction towards sustainability. Accordingly, the feasibility of combinng the concept of sustainabiliry principles and LCA for product development was examined and discussed. This combination was found to yield a simplified method well suited for screening analysis and product development.  相似文献   

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The International Journal of Life Cycle Assessment - In France, agricultural recycling of organic waste is widespread, but LCIs of organic waste treatments are scarce. This work presents LCIs of...  相似文献   

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Purpose

The purpose of this article is to find a suitable life cycle assessment (LCA) method to quantify the most important environmental burdens caused by construction processes of torrent control structures. To find these environmental burdens, 17 construction projects of the “Austrian Service for Torrent and Avalanche Control” (WLV) were analyzed using the “cradle to gate with options” LCA methodology (CEN, 2013).

Methods

This article explains an LCA methodology for the product stage and the construction process of torrent control structures following existing standards. The iterative approach of LCA methodology (ISO, 2006a) was used to record all important processes of the system and to supplement missing information. The LCA methodology has been developed from existing standards of the construction and product sector. Since the production of some construction materials takes place locally, the generic data, for Austria, was adapted. Wood inherent biogenic carbon and primary energy, used as raw material, are treated as materials inherent properties (CEN, 2014). The contribution of the various processes was reproduced by hotspot.

Results and discussion

Hotspots of the different stages are related to the construction materials used. The emissions and primary energy inputs in the product stage are clearly dominated by concrete and steel. If these two materials are used sparingly, the focus is on machine application and transportation. Depending on the selected scenarios, the smallest share of emissions, in relation to the total result of product and construction stage emitted by transport, is 3% and the maximum share is 69%. The greatest environmental impacts in the construction stage are caused by excavation work and transportation on-site. With an average of 4% in the construction stage, the transport of workers to the construction site cannot be neglected as is done in the building sector.

Conclusions

The conclusion of this study is that existing LCA models can be adapted to protective structures. In contrast to conventional buildings, the construction process and transportation are much more important and cannot be neglected. Shifting the hotspots to these processes requires specific calculation rules for that particular field. There is still a need for research to find a suitable functional unit and to develop a methodology for the use and end of life stage of these structures.

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We report that Brucella abortus and Brucella melitensis agglutinate human (A+ and B+), hamster and rabbit erythrocytes, a heretofore undescribed feature in this genus. This activity was associated with a 29-kDa surface protein (SP29) that bound selectively to these erythrocytes and this binding was inhibited by rabbit anti-SP29 antibodies. Hemagglutination was inhibited by pretreatment of erythrocytes with neuraminidase and by preincubation of B. abortus with chondroitin sulfate, N-acetylneuraminic acid and N-acetylneuramin-lactose.  相似文献   

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The International Journal of Life Cycle Assessment - The objective of this paper is to open a discussion on the implications and challenges of including positive impacts in LCAs of products and to...  相似文献   

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The somatic embryogenic process was investigated using immature and mature zygotic embryos originating from 13 open-pollinated seed families selected for their embryogenic capacity from over 128 seed families of Pinus strobus. In a first step, intact megagametophytes with precotyledonary embryos from these families were placed on modified Litvay medium. Embryogenic tissues (ETs) were obtained for 12 of them, with initiation rates varying from 2.6% to 23%. On average, 14% of the ETs (36/258) formed stable embryogenic cell lines (ECLs) after 4–6 months of subculture. Mature somatic embryos were produced for 30 out of 52 cell lines, and plants were regenerated. Later, initiation of ETs from mature zygotic embryos was also tested for the selected families. ECLs were obtained for five of them, with a maximum initiation rate of 2.7%, and plants were produced for four ECLs. Received: 19 March 1998 / Revision received: 22 May 1998 / Accepted: 5 June 1998  相似文献   

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Background, aim, and scope  

Life cycle assessment (LCA) was initially developed to answer questions about the environmental impact of available products and services, implying that the product system under study was possible to investigate in detail; however, if new products or processes are to be evaluated, several complications occur. So, this paper aims to review the methodological issues that need careful attention when LCA is used for evaluating novel products, processes, or production from an environmental standpoint, as well as to draw some recommendations related to the best approach when dealing with them.  相似文献   

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This very interesting Discussion Forum showed the different points of view of basic science and applied science in practice concerning environmental labeling and the lacking comparability between them. Practitioners and consumers stated the large amount of labels. At this point environmental key-parameter models like the one presented for green electricity could be an option. For LCA-researchers it was clear that environmental labeling ought to be connected to an LCA or a comparable environmental valuation method. ISO offers four types of labels and if every label on the market would be ISO-conform and declared as such, comparisons would be much easier. Practitioners from companies stated that a lot of environmental data about there products gained from LCA or similar methods is available, but that the consumer is not yet interested in this kind of information. But in any case their companies will go on issuing environmental declarations for products, hoping that in the long run consumer’s interest and choice will include environmental performance. The discussion in the panel also showed that social aspects are not preferably integrated in an environmental declaration but separate in a social declaration because the evaluation methods are totally different. In any case, the interest of the consumer in the social circumstances of the production of goods is steadily increasing.  相似文献   

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Reaction mechanisms of polyphenolic antioxidants were studied using electrochemical methods (flow column electrolysis and cyclic voltammetry). In flow column electrolysis, the numbers (ns) of electrons involved in the oxidation of catechols (chlorogenic acid and caffeic acid) became larger than two (i.e. the number of -OH moieties) at pH > 7; the n-values finally reached ca. 4 at pH 10. Other polyphenols including catechin, ellagic acid, and curcumin exhibited higher n-values than the numbers of -OH moieties in the whole pH range studied (4 < pH < 10). Such unusually large n-values for polyphenols were found to correlate to their irreversible behavior in cyclic voltammetry. A digital simulation analysis of the voltammograms of chlorogenic acid clearly showed that the electrode reaction at higher pHs can be elucidated in terms of a quasi-reversible electron transfer followed by a chemical reaction and also suggested that the chemical reaction is of second order to the concentration of chlorogenic acid, i.e. a dimerization reaction. In a similar manner, polyphenolic antioxidants generally undergo certain chemical reactions on the occasion of their oxidation. As a result, some oxidizable, phenolic -OH moieties are reproduced in the polymeric products. The unusually large n-values of polyphenols and thus their higher radical scavenging activities may be ascribed to such reproduction of -OH moieties by oxidative polymerization.  相似文献   

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Mutant cell lines derived from a variety of organisms can be isolated when a sufficient number of clones are screened. We describe techniques which can be used to clone up to 104 cells/h. The construction of a simple multiple pipet is outlined and its operation in conjunction with multitest culture trays and an efficient replicator is described. The techniques permit screening of any cells able to grow clonally in culture.  相似文献   

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