33 research outputs found

    Improved Alternatives for Estimating In-Use Material Stocks

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    Determinations of in-use material stocks are useful for exploring past patterns and future scenarios of materials use, for estimating end-of-life flows of materials, and thereby for guiding policies on recycling and sustainable management of materials. This is especially true when those determinations are conducted for individual products or product groups such as ā€œautomobilesā€ rather than general (and sometimes nebulous) sectors such as ā€œtransportationā€. We propose four alternatives to the existing topā€“down and bottomā€“up methods for estimating in-use material stocks, with the choice depending on the focus of the study and on the available data. We illustrate with aluminum use in automobiles the robustness of and consistencies and differences among these four alternatives and demonstrate that a suitable combination of the four methods permits estimation of the in-use stock of a material contained in all products employing that material, or in-use stocks of different materials contained in a particular product. Therefore, we anticipate the estimation in the future of in-use stocks for many materials in many products or product groups, for many regions, and for longer time periods, by taking advantage of methodologies that fully employ the detailed data sets now becoming available

    Anthropogenic Cycles of the Elements: A Critical Review

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    A cycle is the quantitative characterization of the flows of a specific material into, within, and from a given system. An anthropogenic elemental cycle can be static (for a point in time) or dynamic (over a time interval). The about 350 publications collected for this review contain a total of 1074 individual cycle determinations, 989 static and 85 dynamic, for 59 elements; more than 90% of the publications have appeared since 2000. The cycles are of varying quality and completeness, with about 80% at country- or territory-level, addressing 45 elements, and 5% at global-level, addressing 30 elements. Despite their limitations, cycles have often been successful in revealing otherwise unknown information. Most of the elements for which no cycles exist are radioactively unstable or are used rarely and in small amounts. For a variety of reasons, the anthropogenic cycles of only perhaps a dozen elements are well characterized. For all the others, with cycles limited or nonexistent, our knowledge of types of uses, lifetimes in those uses, international trade, losses to the environment, and rates of recycling is quite limited, thereby making attempts to evaluate resource sustainability particularly problematic

    Inter-Sectoral Bisphenol A (BPA) Flows in the 2012 Chinese Economy

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    Bisphenol A (BPA), a widely used petrochemical compound, has become an emerging global environmental management challenge because its leakage is associated with potential environmental and human health impacts. Until now, available BPA statistics have been limited to the products that directly use BPA. In this study, we delineate direct and indirect BPA flows for the 2012 Chinese economy. We find that construction, production of educational and recreational products, and automobile manufacturing are the most BPA-intensive sectors in terms of total BPA flows (300, 157, and 130 Gg total BPA flows, respectively). The public management and health sectors, however, incur significant indirect BPA flows, defined as embedded and inter-sectoral BPA placed into use, even though direct BPA use by these sectors is limited. By revealing the currently overlooked indirect BPA flows, this study reveals data gaps that are highly relevant to improving the accuracy of estimated BPA flows and losses. The method used herein is transferrable to other emerging and environmentally relevant materials, thereby providing the holistic understanding needed for cities, regions, or nations to design effective policy interventions

    Dynamic Stocks and Flows Analysis of Bisphenol A (BPA) in China: 2000ā€“2014

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    Bisphenol A (BPA), a synthetic organic chemical, is creating a new category of ecological and human health challenges due to unintended leakage. Effectively managing the use and leakage of BPA can benefit from an understanding of the anthropogenic BPA cycles (i.e., the size of BPA flows and stocks). In this work, we provide a dynamic analysis of the anthropogenic BPA cycles in China for 2000ā€“2014. We find that Chinaā€™s BPA consumption has increased 10-fold since 2000, to āˆ¼3 million tonnes/year. With the increasing consumption, Chinaā€™s in-use BPA stock has increased 500-fold to 14.0 million tonnes (i.e., 10.2 kg BPA/capita). It is unclear whether a saturation point has been reached, but in 2004ā€“2014, Chinaā€™s in-use BPA stock has been increasing by 0.8 kg BPA/capita annually. Electronic products are the biggest contributor, responsible for roughly one-third of Chinaā€™s in-use BPA stock. Optical media (DVD/VCD/CDs) is the largest contributor to Chinaā€™s current End-of-Life (EoL) BPA flow, totaling 0.9 million tonnes/year. However, the EoL BPA flow due to e-waste will increase quickly, and will soon become the largest EoL BPA flow. The changing quantities and sources of EoL BPA flows may require a shift in the macroscopic BPA management strategies

    Building the Material Flow Networks of Aluminum in the 2007 U.S. Economy

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    Based on the combination of the U.S. economic input-output table and the stocks and flows framework for characterizing anthropogenic metal cycles, this study presents a methodology for building material flow networks of bulk metals in the U.S. economy and applies it to aluminum. The results, which we term the Inputā€“Output Material Flow Networks (IO-MFNs), achieve a complete picture of aluminum flow in the entire U.S. economy and for any chosen industrial sector (illustrated for the Automobile Manufacturing sector). The results are compared with information from our former study on U.S. aluminum stocks and flows to demonstrate the robustness and value of this new methodology. We find that the IO-MFN approach has the following advantages: (1) it helps to uncover the network of material flows in the manufacturing stage in the life cycle of metals; (2) it provides a method that may be less time-consuming but more complete and accurate in estimating new scrap generation, process loss, domestic final demand, and trade of final products of metals, than existing material flow analysis approaches; and, most importantly, (3) it enables the analysis of the material flows of metals in the U.S. economy from a network perspective, rather than merely that of a life cycle chain

    Building the Material Flow Networks of Aluminum in the 2007 U.S. Economy

    No full text
    Based on the combination of the U.S. economic input-output table and the stocks and flows framework for characterizing anthropogenic metal cycles, this study presents a methodology for building material flow networks of bulk metals in the U.S. economy and applies it to aluminum. The results, which we term the Inputā€“Output Material Flow Networks (IO-MFNs), achieve a complete picture of aluminum flow in the entire U.S. economy and for any chosen industrial sector (illustrated for the Automobile Manufacturing sector). The results are compared with information from our former study on U.S. aluminum stocks and flows to demonstrate the robustness and value of this new methodology. We find that the IO-MFN approach has the following advantages: (1) it helps to uncover the network of material flows in the manufacturing stage in the life cycle of metals; (2) it provides a method that may be less time-consuming but more complete and accurate in estimating new scrap generation, process loss, domestic final demand, and trade of final products of metals, than existing material flow analysis approaches; and, most importantly, (3) it enables the analysis of the material flows of metals in the U.S. economy from a network perspective, rather than merely that of a life cycle chain

    Anthropogenic Cycles of Arsenic in Mainland China: 1990ā€“2010

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    Arsenic (As) is a trace element in the global environment with toxicity to both humans and ecosystem. This study characterizes Chinaā€™s historical anthropogenic arsenic cycles (AACs) from 1990 to 2010. Key findings include the following: (1) the scale of Chinaā€™s AACs grew significantly during the studied period, making China the biggest miner, producer, and user of arsenic today; (2) the majority of arsenic flows into Chinaā€™s anthroposphere are the impurity of domestically mined nonferrous metal ores, which far exceeds domestic intentional demands; (3) China has been a net exporter of arsenic trioxide and arsenic metalloid, thus suffering from the environmental burdens of producing arsenic products for other economies; (4) the growth of arsenic use in China is driven by simultaneous increases in many applications including glass making, wood preservatives, batteries, semiconductors, and alloys, implying the challenge for regulating arsenic uses in multiple applications/industries at the same time; (5) the dissipative arsenic emissions resulting from intentional applications are at the same order of magnitude as atmospheric emissions from coal combustion, and their threats to human and ecosystem health can spread widely and last years to decades. Our results demonstrate that the characterization of AACs is indispensable for developing a complete arsenic emission inventory

    2-DE image of AvastinĀ® is shown providing assignments of identified protein spots.

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    <p>2-DE image of AvastinĀ® is shown providing assignments of identified protein spots.</p

    The modifications verified by HCT and Orbitrap.

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    <p>The modifications verified by HCT and Orbitrap.</p
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