Environmental and economic evaluation of supply loops and their constraints

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Production, use, and fate of all plastics ever made

© The Author(s), 2017. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Science Advances 3 (2017): e1700782, doi:10.1126/sciadv.1700782.Plastics have outgrown most man-made materials and have long been under environmental scrutiny. However, robust global information, particularly about their end-of-life fate, is lacking. By identifying and synthesizing dispersed data on production, use, and end-of-life management of polymer resins, synthetic fibers, and additives, we present the first global analysis of all mass-produced plastics ever manufactured. We estimate that 8300 million metric tons (Mt) as of virgin plastics have been produced to date. As of 2015, approximately 6300 Mt of plastic waste had been generated, around 9% of which had been recycled, 12% was incinerated, and 79% was accumulated in landfills or the natural environment. If current production and waste management trends continue, roughly 12,000 Mt of plastic waste will be in landfills or in the natural environment by 2050.R.G. was supported by the NSF Chemical, Bioengineering, Environmental and Transport Systems grant #1335478

Life Cycle Aware Computing: Reusing Silicon Technology

Despite the high costs associated with processor manufacturing, the typical chip is used for only a fraction of its expected lifetime. Reusing processors would create a food chain of electronic devices that amortizes the energy required to build chips over several computing generations

Coupling GIS and LCA for biodiversity assessments of land use

Geospatial details about land use are necessary to assess its potential impacts on biodiversity. Geographic information systems (GIS) are adept at modeling land use in a spatially explicit manner, while life cycle assessment (LCA) does not conventionally utilize geospatial information. This study presents a proof-of-concept approach for coupling GIS and LCA for biodiversity assessments of land use and applies it to a case study of ethanol production from agricultural crops in California. GIS modeling was used to generate crop production scenarios for corn and sugar beets that met a range of ethanol production targets. The selected study area was a four-county region in the southern San Joaquin Valley of California, USA. The resulting land use maps were translated into maps of habitat types. From these maps, vectors were created that contained the total areas for each habitat type in the study region. These habitat compositions are treated as elementary input flows and used to calculate different biodiversity impact indicators in a second paper (Geyer et al., submitted). Ten ethanol production scenarios were developed with GIS modeling. Current land use is added as baseline scenario. The parcels selected for corn and sugar beet production were generally in different locations. Moreover, corn and sugar beets are classified as different habitat types. Consequently, the scenarios differed in both the habitat types converted and in the habitat types expanded. Importantly, land use increased nonlinearly with increasing ethanol production targets. The GIS modeling for this study used spatial data that are commonly available in most developed countries and only required functions that are provided in virtually any commercial or open-source GIS software package. This study has demonstrated that GIS-based inventory modeling of land use allows important refinements in LCA theory and practice. Using GIS, land use can be modeled as a geospatial and nonlinear function of output. For each spatially explicit process, land use can be expressed within the conventional structure of LCA methodology as a set of elementary input flows of habitat types

Korištenje Lewisovih stanica u istraživanju enzimske kinetike (S)-hidroksinitril liaze u dvofaznom sustavu

(S)-Hydroxynitrile lyase from Hevea brasiliensis (HbHnl) (EC 4.1.2.39) catalyzes the reversible synthesis of chiral cyanohydrins from aldehydes or ketones and HCN. The enzymatic formation of (S)-mandelonitrile (MN) from benzaldehyde (BA) and HCN was studied in two-phase systems of buffer and organic solvents (diisopropyl ether, methyl-t-butyl ether) using a Lewis cell to investigate the interaction between mass transfer and the biocatalytic reaction. The enzymatic reaction rate in the aqueous phase saturated with organic solvents is drastically reduced in comparison to pure buffer due to the increase of the Michaelis-Menten constants of the substrates. Mass transfer of the substrates from the organic to the aqueous phase and mass transfer of the product in the opposite direction could be described by the two-film theory. The formation of (S)-mandelonitrile in the Lewis cell follows an aqueous phase distributed reaction model, which means that the enzymatic reaction takes place in the bulk of the aqueous phase and in the thin film close to the interface and/or directly at the interface. Using the Hatta number it could be shown that the mass transfer of benzaldehyde from the organic to the aqueous phase is enhanced by the biocatalytic reaction of the (S)-hydroxynitrile lyase from Hevea brasiliensis.(S)-hidroksinitril liaza iz Hevea brasiliensis (HbHnl) (EC 4.1.2.39) katalizira reverzibilnu sintezu kiralnih cianohidrina iz aldehida ili ketona i HCN. Enzimska sinteza (S)-mandelonitrila (MN) iz benzaldehida (BA) i HCN ispitivana je u dvofaznim sustavima pufera i organskih otapala (diizopropileter, metil-t-butileter) koristeći Lewisovu stanicu kako bi se istražilo međudjelovanje prijenosa mase i biokatalitičke reakcije. Brzina enzimske reakcije u vodenoj fazi, zasićenoj organskim otapalima, drastično je smanjena u usporedbi s reakcijom u čistom puferu zbog povišenja Michaelis-Mentenove š konstante supstrata. Prijenos mase supstrata iz organske u vodenu fazu te prijenos mase produkta u suprotnom smjeru može se opisati teorijom dvostrukog filma. Stvaranje (S)-mandelonitrila u Lewisovoj stanici slijedi reakcijski model u vodenoj fazi, što znači da se enzimska reakcija provodi uglavnom u vodenoj fazi i u tankom filmu u blizini međufaze odnosno izravno na međufazi. Koristeći Hattin broj moglo se pokazati da je prijenos mase benzaldehida iz organske u vodenu fazu pojačan biokatalitičkom reakcijom (S)-hidroksinitril liaze iz Hevea brasiliensis

Comparison of Three Extraction Methods for 17β-Estradiol in Sand, Bentonite, and Organic-Rich Silt Loam

Extraction is an important procedure for samples that contain soil because other compounds in soil may affect analysis of estrogens. This study was conducted to evaluate three different extraction methods for 17β-estradiol in soil. Sand, bentonite, and organicrich silt loam were spiked with 1 mg kg −1 of 17β-estradiol as a model compound of estrogens. 17β-estradiol and its metabolites, estrone and estriol, were extracted using (i) a modified Bligh and Dyer extraction, (ii) a pressurized fluid extraction, and (iii) a diethyl ether extraction, and measured by liquid chromatography tandem mass spectrometry. There were significant differences in the extraction efficiency for 17β-estradiol among the extraction methods and the soils: the efficiencies ranged from 10% to 97%. Overall, the diethyl ether extraction method had the largest efficiency of 17β-estradiol with 45% and 57% for bentonite and silt loam, respectively. Transformation of 17β-estradiol to estrone and estriol in the different extraction methods was less than 3.6% during the extraction procedures. This study underlined the importance of sample preparation for estrogen analysis in soil samples

The role of an efficient characterization of plant extracts for breeding and the transition from wild collection to controlled cultivation

Die Inkulturnahme noch nicht fest etablierter Heil- und Gewürzpflanzen steht vor folgendem Dilemma: Einerseits ist eine steigende Nachfrage nach Ware aus kontrolliertem, dokumentiertem, überprüfbarem, heimischem Anbau zu verzeichnen und eine Erhöhung der Anbauflächen dieser Arten politisch gewünscht. Andererseits wird die Anbauware im Preis, je nach Versorgungslage, mit dem Preis der Ware aus Wildsammlungen verglichen. Bei vergleichbaren Qualitäten erhält dann in der Regel die preiswertere Wildsammelware den Vorzug im Einkauf. Dies führt dazu, dass eine kontinuierliche Versorgung der Verarbeitungsbetriebe mit Ware aus kontrolliertem Anbau immer wieder zusammenbricht, da die Anbauer sich nicht auf Preise und Abnahme verlassen können. Auswege aus diesem Dilemma bestehen darin, entweder mit dem Anbau zu warten, bis die Wildsammlungen versagen oder das anzubauende Material qualitativ deutlich von der Wildsammelware abzugrenzen. An den Beispielen Echte Arnika (Arnica montana L.) und Russischer Löwenzahn (Taraxacum kok-saghyz L.E.Rodin) wird gezeigt, dass - vom Wildmaterial ausgehend - in den ersten Selektionszyklen enorm große Zuchtfortschritte erzielt werden können; vorausgesetzt die Ziele sind klar definiert und es steht eine ausreichende Analytik-Kapazität zur Verfügung. Eine solche kann beispielweise mittels moderner Kernspinresonanzspektroskopie (NMR) mit entsprechender software-basierter Datenanalyse realisiert werden und wird im Folgenden, im oben genannten Kontext, diskutiert.The cultivation of not yet well-established medicinal and herbal plants faces the following dilemma: On the one hand there is an increasing demand for goods from controlled, documented, verifiable, domestic cultivation and an increase in the acreage of these species is politically desired. On the other hand, the cultivated product is compared in price, depending on the supply situation, with the price of the product from wild collections. Usually, this results in the use of the cheaper wild collected goods. As a result, the continuous supply of raw material from controlled cultivation to the processing plants collapses time and again as growers can not rely on prices and acceptance. The solution to this dilemma is either to wait with the cultivation until the wild collections fail or the quality of the material to be grown is clearly differentiated from the wild collection. Based on two examples, Arnica (Arnica montana L.) and Russian Dandelion (Taraxacum kok-saghyz L.E.Rodin), is demonstated that - starting from the wild material - high breeding progress can be achieved in the first selection cycles. A necessary precondition is, that the goals are clearly defined and that there is sufficient capacity available to analyze output traits and lead ingredients. Such can be realized for example by means of modern nuclear magnetic resonance (NMR) analysis techniques with appropriate software-based data analysis and will be discussed below