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Printed and tablet e-paper newspaper from an environmental perspective - A screening life cycle assessment
DOE Office of Scientific and Technical Information (OSTI.GOV)
Moberg, Asa, E-mail: asa.moberg@infra.kth.s; STFI-Packforsk, PO Box 5604, SE 114 86 Stockholm; KTH, Royal Institute of Technology, Centre for Sustainable Communications, SE 100 44 Stockholm
2010-04-15
Viable alternatives to conventional newspapers, such as electronic papers, e-papers or e-readers, are intended to have many of the qualities of paper, such as reading using reflective light, high resolution, 180 deg. viewing angle. It has been suggested that the environmental impact of e-paper can be lower than for printed and internet-based newspapers. However, in order to find the facts of the matter, a thorough life cycle perspective covering raw material acquisition, production, use and disposal should preferably be used to study the environmental performance of the different products. A screening life cycle assessment was performed to describe the potentialmore » environmental impacts of two product systems; printed on paper and tablet e-paper newspapers. Results show that the most significant phase of the life cycle for both product systems was the production of substrate or platform. Accordingly, key aspects that may affect the resulting environmental performance of newspaper product systems were for the printed newspaper number of readers per copy and number of pages per issue and for the tablet e-paper newspaper lifetime and multi-use of the device. The printed newspaper in general had a higher energy use, higher emissions of gases contributing to climate change and several other impact categories than the tablet e-paper newspaper. It was concluded that tablet e-paper has the potential to decrease the environmental impact of newspaper consumption. However, further studies regarding the environmental impact of production and waste management of electronic devices and internet use, as well as more comprehensive assessment of toxicological impacts are needed. As the data on the electronic devices becomes more comprehensive this may prove to be a major limitation of electronic newspaper systems. Developers are suggested to strive towards minimisation of toxic and rare substances in production.« less
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Drop Impact Dynamics with Sessile Drops and Geometries: Spreading, Jetting, and Fragmentation
NASA Astrophysics Data System (ADS)
Tilger, Christopher F.
The tendency of surface tension to cause small parcels of fluid to form into drops allows convenient packaging, transport, dispersal of liquid phase matter. Liquid drop impacts with solids, liquids, and other drops have realized and additional future applications in biological, manufacturing, heat transfer, and combustion systems. Experiments were conducted to investigate the dynamics of multiple drop collisions, rather than the most-studied phenomenon of single drop impacts. Additional drop impacts were performed on rigid hemispheres representing sessile drops, angled substrates, and into the vertex of two tilted surfaces arranged into a vee shape. A qualitative inspection of drop-sessile drop impacts shows distinct post-impact shapes depending on the offset distance between the drops. At intermediate offset distances, distinct jets issue from the overlap region between the two drops projected areas. These jets are observed to reach their maximum extent at a critical offset distance ratio, epsilon epsilon ˜ 0.75-0.80, with substrate contact angle and W e having a lesser effect. Capillary waves that traverse the sessile drop after collision cause a lower aspect ratio liquid column to emanate from the sessile drop opposite the impact. In order to better understand the jetting phenomenon seen in the offset drop-sessile drop impacts, simpler solid geometries are investigated that elicit a similar behavior. Solid hemispheres do not show the singular jetting observed in the fluidic case, however, a simple vee formed by two intersection planar substrates do jet in a similar fashion to the fluidic case. A geometric model with partnered experiments is developed to describe the bisymmetric spread of an impacting drop on an angled substrate. This geometric model is used to guide a time of arrival based model for various features of the drop impact, which is used to predict jetting in various vee channel experiments.
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Publishing large DNA sequence data in reduced spaces and lasting formats, in paper or PDF.
PubMed
Aguiar, Alexandre Pires
2013-02-04
Scientific publications carry a practical moral duty: they must last. Along that line of thinking, some methods are proposed to allow economically and structurally viable publication of DNA sequence data of any size in printed matter and PDFs. The proposal is primarily aimed at contributing for preserving information for the future, while allowing authors to avoid information splitting and complement storage ex situ, that is, in server machines, outside the publication proper. The technique may also help to solve the impasse between the ICZN Code requirement that a new nomen be associated to diagnostic characters for the taxon vs. the phylogenetic definition of taxa, based on cladograms only: sequence data are characters, and can now be easily and comfortably included in taxonomic publications, with direct textual mention to their diagnostic sections. The compression level achieved allows the inclusion of all wanted DNA or RNA sequences in the same printed matter or PDF publications where the sequences are cited and discussed. Reduced font sizes, invisible fonts, and original 2D black & white and color barcodes are illustrated and briefly discussed. The level of data compression achieved can allow each full page of sequence data, or about 5000 characters, to be precisely coded into a color barcode as small as a square of 1.5 mm. A practical example is provided with Taeniogonalos woodorum Smith (Hymenoptera, Trigonalidae). Free software to generate publishable barcodes from txt or FASTA files is provided at www.systaxon.ufes.br/dna.
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Distilling reliable remedies: Hieronymus Brunschwig's Liber de arte distillandi (1500) between alchemical learning and craft practice.
PubMed
Taape, Tillmann
2014-08-01
Hieronymus Brunschwig's Liber de arte distillandi, written in German and first published in Strasbourg in 1500, was the first printed manual on the distillation of medicinal waters. Although influential among early modern audiences and well known to modern scholars, its intriguing blend of intellectual and practical traditions has thus far received little attention. This paper identifies these strands in Brunschwig's technical instructions and shows how they intertwine in the production of reliable remedies. Exploring the intellectual dimension of Brunschwig's work, I argue that his concept of distillation is shaped by an alchemical understanding of matter, especially by the writings on 'quintessence' of the fourteenth-century alchemist John of Rupescissa. To realise this concept in the workshop, Brunschwig emphasises the central importance of the body and its senses to ensure true craftsmanship. Brunschwig's printed manual was as much a product of skilled artisanal practices as the distilled waters it describes, and I argue that it was shaped by the same concerns about technical precision and reliability.
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Online literature-retrieval systems: how to get started.
PubMed
Tousignaut, D R
1983-02-01
Basic information describing online literature-retrieval systems is presented; the power of online searching is also discussed. The equipment, expense involved, and training necessary to perform online searching efficiently is described. An individual searcher needs only a computer terminal and a telephone; by telephone, the searcher connects with an online vendor's computer at another location. The four major U.S. vendors (Dialog, Bibliographic Retrieval Services, Systems Development Corporation, and the National Library of Medicine) are compared. A step-by-step procedure of logging in and searching is presented. Using the International Pharmaceutical Abstracts database as an example, 17 access points to locating an article via an online system are compared with only two (the subject and author index entry) of a printed service. By searching online, one can search the published literature on a specific topic in a matter of minutes. An online search is very useful when limited information is available or the search question contains a term that is not in a printed index.
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Stable carbon isotope analyses of nanogram quantities of particulate organic carbon (pollen) with laser ablation nano combustion gas chromatography/isotope ratio mass spectrometry
PubMed Central
Sluijs, Appy; Laks, Jelmer J.; Reichart, Gert‐Jan
2016-01-01
Rationale Analyses of stable carbon isotope ratios (δ 13C values) of organic and inorganic matter remains have been instrumental for much of our understanding of present and past environmental and biological processes. Until recently, the analytical window of such analyses has been limited to samples containing at least several μg of carbon. Methods Here we present a setup combining laser ablation, nano combustion gas chromatography and isotope ratio mass spectrometry (LA/nC/GC/IRMS). A deep UV (193 nm) laser is used for optimal fragmentation of organic matter with minimum fractionation effects and an exceptionally small ablation chamber and combustion oven are used to reduce the minimum sample mass requirement compared with previous studies. Results Analyses of the international IAEA CH‐7 polyethylene standard show optimal accuracy, and precision better than 0.5‰, when measuring at least 42 ng C. Application to untreated modern Eucalyptus globulus (C3 plant) and Zea mays (C4 plant) pollen grains shows a ~ 16‰ offset between these species. Within each single Z. mays pollen grain, replicate analyses show almost identical δ 13C values. Conclusions Isotopic offsets between individual pollen grains exceed analytical uncertainties, therefore probably reflecting interspecimen variability of ~0.5–0.9‰. These promising results set the stage for investigating both δ 13C values and natural carbon isotopic variability between single specimens of a single population of all kinds of organic particles yielding tens of nanograms of carbon. © 2016 The Authors. Rapid Communications in Mass Spectrometry Published by John Wiley & Sons Ltd. PMID:27766694
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Carbon stable isotope composition of DNA isolated from an incipient paleosol
NASA Astrophysics Data System (ADS)
Jahren, A. Hope; Kelm, Kellie; Wendland, Beverly; Petersen, Gitte; Seberg, Ole
2006-05-01
We determined the carbon isotope (δ13C) value of double-stranded DNA (dsDNA) isolated from the organic horizons of a Delaware soil that is actively being covered by an encroaching sand dune. The soil belongs to a Nymphaea odorata Ait. (water lily) wetland, and we regard its active acquisition of a thick (˜24 cm) surface mantle to embody the process of paleopedogenesis; therefore, we have termed it an “incipient paleosol.” In this study, we compared the δ13C value of paleosol dsDNA to the bulk δ13C value of N. odorata, as well as to the δ13C value of plants that had colonized the surface mantle. The isotopic offset between paleosol δ13CdsDNA and N. odorata δ13Ctissue was identical to the relationship between δ13CdsDNA and δ13Ctissue for tracheophytes, which we had previously determined. In contrast, the isotopic offset between paleosol δ13CdsDNA and the δ13Ctissue of plants colonizing the surface mantle differed from this relationship by as much as 4‰. Similarly, the δ13C value of bulk paleosol organic matter was extremely heterogeneous and varied across 6‰. All paleosol DNA polymerase chain reaction (PCR) products produced clear, sharp, 350 base-pair (bp) fragments of rbcL, a gene shared by all photosynthetic organisms. These results open the exciting possibility that stable isotope analysis of dsDNA isolated from paleosol organic matter can be used to infer the δ13C value of the plant that dominated the nucleic acid contribution.
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Holocene provenance shift of suspended particulate matter in the Amazon River basin
NASA Astrophysics Data System (ADS)
Höppner, Natalie; Lucassen, Friedrich; Chiessi, Cristiano M.; Sawakuchi, André O.; Kasemann, Simone A.
2018-06-01
The strontium (Sr), neodymium (Nd) and lead (Pb) isotope signatures of suspended particulate matter (SPM) in rivers reflect the radiogenic isotope signatures of the rivers' drainage basin. These signatures are not significantly affected by weathering, transport or depositional cycles, but document the sedimentary contributions of the respective sources. We report new Sr, Nd and Pb isotope ratios and element concentrations of modern SPM from the Brazilian Amazon River basin and document the past evolution of the basin by analyzing radiogenic isotopes of a marine sediment core from the slope off French Guiana archiving the last 40 kyr of Amazon River SPM, and the Holocene section of sediment cores raised between the Amazon River mouth and the slope off French Guiana. The composition of modern SPM confirms two main source areas, the Andes and the cratonic Shield. In the marine sediment core notable changes occurred during the second phase of Heinrich Stadial 1 (i.e. increased proportion of Shield rivers SPM) and during the last deglaciation (i.e. increased proportion of Madeira River SPM) together with elsewhere constant source contributions. Furthermore, we report a prominent offset in Sr and Nd isotopic composition between the average core value (εNd: -11.7 ± 0.9 (2SD), 87Sr/86Sr: 0.7229 ± 0.0016 (2SD)) and the average modern Amazon River SPM signal (εNd: -10.5 ± 0.5 (2SD), 87Sr/86Sr: 0.7213 ± 0.0036 (2SD)). We suggest that a permanent change in the Amazon River basin sediment supply during the late Holocene to a more Andean dominated SPM was responsible for the offset.
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On the laws for the emergence of life from the abiotic matter
NASA Astrophysics Data System (ADS)
Kolb, Vera M.
2012-10-01
In this work we pose a question if the laws for the emergence of life from the abiotic matter can exist even before carbon and the organic compounds were available. Carbon as an element became available via nucleosynthesis in the stars, and various carbon compounds were later made in the interstellar space and on the various objects in space. Is the emergence of life blue-printed as some general law which would then guarantee that life would evolve in the universe, or is it a law which co-evolved with the organic compounds and the environment in which they existed and which may be a subject to chance? This question is of a fundamental importance for astrobiology, which seeks extraterrestrial life without really knowing if it exists. Numerous articles and books have been written on the subject of the inevitability of life in the universe, on the evolution of matter which leads to life, and on the role of chance in the emergence of life. We select from these resources, critically examine them, and provide an inclusive summary, which we believe will be useful to astrobiologists.
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Probing high-redshift clusters with HST/ACS gravitational weak-lensing and Chandra x-ray observations
NASA Astrophysics Data System (ADS)
Jee, Myungkook James
2006-06-01
Clusters of galaxies, the largest gravitationally bound objects in the Universe, are useful tracers of cosmic evolution, and particularly detailed studies of still-forming clusters at high-redshifts can considerably enhance our understanding of the structure formation. We use two powerful methods that have become recently available for the study of these distant clusters: spaced- based gravitational weak-lensing and high-resolution X-ray observations. Detailed analyses of five high-redshift (0.8 < z < 1.3) clusters are presented based on the deep Advanced Camera for Surveys (ACS) and Chandra X-ray images. We show that, when the instrumental characteristics are properly understood, the newly installed ACS on the Hubble Space Telescope (HST) can detect subtle shape distortions of background galaxies down to the limiting magnitudes of the observations, which enables the mapping of the cluster dark matter in unprecedented high-resolution. The cluster masses derived from this HST /ACS weak-lensing study have been compared with those from the re-analyses of the archival Chandra X-ray data. We find that there are interesting offsets between the cluster galaxy, intracluster medium (ICM), and dark matter centroids, and possible scenarios are discussed. If the offset is confirmed to be uniquitous in other clusters, the explanation may necessitate major refinements in our current understanding of the nature of dark matter, as well as the cluster galaxy dynamics. CL0848+4452, the highest-redshift ( z = 1.27) cluster yet detected in weak-lensing, has a significant discrepancy between the weak- lensing and X-ray masses. If this trend is found to be severe and common also for other X-ray weak clusters at redshifts beyond the unity, the conventional X-ray determination of cluster mass functions, often inferred from their immediate X-ray properties such as the X-ray luminosity and temperature via the so-called mass-luminosity (M-L) and mass-temperature (M-T) relations, will become highly unstable in this redshift regime. Therefore, the relatively unbiased weak-lensing measurements of the cluster mass properties can be used to adequately calibrate the scaling relations in future high-redshift cluster investigations.
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Evidence for changes in subsurface circulation in the late Eocene equatorial Pacific from radiolarian-bound nitrogen isotope values
NASA Astrophysics Data System (ADS)
Robinson, Rebecca S.; Moore, Theodore C.; Erhardt, Andrea M.; Scher, Howie D.
2015-07-01
Microfossil-bound organic matter represents an important archive of surface ocean environmental information. Sedimentary nitrogen (N) isotope reconstructions of surface nitrate consumption and nitrogen source changes are made using fossil diatom (autotrophs) and planktic foraminiferal (heterotrophs)-bound organic matter with success. However, because diatoms and planktic foraminifera are poorly preserved and sedimentary organic matter content is near zero during the late Eocene, our ability to examine nutrient dynamics across this important climate transition is limited. Here we present new data exploring the use of N isotope records from radiolarian tests. A comparison of surface ocean nitrate and core top bulk and radiolarian N isotope values (as δ15N) from the equatorial Pacific indicates that radiolarian-N records δ15N variability with fidelity but that a significant offset exists between bulk sedimentary and diatom δ15N values and those measured from radiolarians (~7.1 ± 1.1‰). A downcore profile of radiolarian δ15N values is compared to siliceous microfossil assemblage changes across the Eocene-Oligocene boundary. Average of radiolarian-bound δ15N values is 0.5 ± 2.0‰, which, when corrected using the offset derived from the modern surface samples, suggests that the mean nitrogen isotopic composition of the early Cenozoic eastern Pacific was not significantly different from today. The overall trend, of decreasing δ15N values with decreasing export productivity, is consistent with either a regional decline in pelagic denitrification or a large-scale change in nutrient sources to the eastern equatorial Pacific (EEP), both linked to the cooling climate and changing intermediate water circulation. Decreasing/low δ15N values cooccur with high radiolarian species turnover at ~35.5 and 34 Ma, suggestive of a significant ecological change in the EEP, consistent with cooling and water mass distribution changes. The preliminary results suggest that radiolarian-bound organic nitrogen represents another promising archive and underscores the fact that the different microfossil fractions must be separated to ensure robust results.
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Mineralogical analysis of dust collected from typical recycling line of waste printed circuit boards.
PubMed
Wang, Fangfang; Zhao, Yuemin; Zhang, Tao; Duan, Chenlong; Wang, Lizhang
2015-09-01
As dust is one of the byproducts originating in the mechanical recycling process of waste printed circuit boards such as crushing and separating, from the viewpoints of resource reuse and environmental protection, an effective recycling method to recover valuable materials from this kind of dust is in urgent need. In this paper, detailed mineralogical analysis on the dust collected from a typical recycling line of waste printed circuit boards is investigated by coupling several analytical techniques. The results demonstrate that there are 73.1wt.% organic matters, 4.65wt.% Al, 4.55wt.% Fe, 2.67wt.% Cu and 1.06wt.% Pb in the dust, which reveals the dust is worthy of reuse and harmful to environment. The concentration ratios of Fe, Mn and Zn can reach 12.35, 12.33 and 6.67 respectively by magnetic separation. The yield of dust in each size fraction is nonuniform, while the yield of -0.75mm size fraction is up to 51.15wt.%; as the particle size decreases, the content of liberated metals and magnetic materials increase, and metals are mainly in elemental forms. The F, Cl and Br elements combing to C in the dust would make thermal treatment dangerous to the environment. Based on these results, a flowsheet to recycle the dust is proposed. Copyright © 2015 Elsevier Ltd. All rights reserved.
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A free-form lensing model of A370 revealing stellar mass dominated BCGs, in Hubble Frontier Fields images
NASA Astrophysics Data System (ADS)
Diego, Jose M.; Schmidt, Kasper B.; Broadhurst, Tom; Lam, Daniel; Vega-Ferrero, Jesús; Zheng, Wei; Lee, Slanger; Morishita, Takahiro; Bernstein, Gary; Lim, Jeremy; Silk, Joseph; Ford, Holland
2018-02-01
We derive a free-form mass distribution for the unrelaxed cluster A370 (z = 0.375), using the first release of the Hubble Frontier Fields images (76 orbits) and GLASS spectroscopy. Starting from a reliable set of 10 multiply lensed systems, we produce a free-form lens model that identifies ≈80 multiple images. Good consistency is found between models using independent subsamples of these lensed systems, with detailed agreement for the well-resolved arcs. The mass distribution has two very similar concentrations centred on the two prominent brightest cluster galaxies (or BCGs), with mass profiles that are accurately constrained by a uniquely useful system of long radially lensed images centred on both BCGs. We show that the lensing mass profiles of these BCGs are mainly accounted for by their stellar mass profiles, with a modest contribution from dark matter within r < 100 kpc of each BCG. This conclusion may favour a cooled cluster gas origin for BCGs, rather than via mergers of normal galaxies for which dark matter should dominate over stars. Growth via merging between BCGs is, however, consistent with this finding, so that stars still dominate over dark matter. We do not observe any significant offset between the positions of the peaks of the dark matter distribution and the light distribution.
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Dependencies between soft proofing and prepress production
NASA Astrophysics Data System (ADS)
Tuijn, Chris
2008-01-01
In order to save time and money, more and more printing organizations are investing in on-line customer portals to allow uploading content and giving formal approvals based on soft proofs before the final production process (plate making and printing) can be initiated. The approvals are typically made on soft proofs of pages whereas, obviously, the images used for plate making are so-called imposed flats (a combination of pages rotated in such a way that the printed matter can be obtained after folding and cutting). The main goal of a soft proof of a page is to simulate accurately on a display device how the page will be finally printed. The quality expectations of a soft proof are very high since a formal approval implies contractual obligations from the printing organization. This quality, however, can be influenced by many parameters. By definition, soft proofs will be displayed on a monitor (being a light emitting device), whereas a print on paper can only be seen as the reflection of a light source. As a consequence, monitors can be described by an additive color model whereas printers or presses will be modeled by a subtractive color model. Other differences relate to how the image is generated: presses can only output binary information (ink or no ink) and continuous tones are simulated by using screening techniques whereas, on a monitor, a multi-level signal can generate different shades of a specific color. The differences described above are addressed by many color management systems available on the market today. An upcoming requirement in this area is that people do not only expect the color management software to behave well but also expect this software to validate its behavior. Another range of problems with soft proofs relates to the rendering (converting vector-based page data into bitmaps) and separation process. These can be divided in two classes: spatial issues (related to resolution differences, high-frequency patterns, aliasing problems etc.) and issues related to object layering (overprint and transparency issues). Also when optimizations are carried out for plate reuse across versioned products, many things can go wrong. In this paper, we will categorize the different potential problems occurring with soft proofs and examine in detail how these problems can be avoided. It will turn out that this can only be realized if one knows the details on how the printing plates will be generated in prepress production.
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A correlative imaging based methodology for accurate quantitative assessment of bone formation in additive manufactured implants.
PubMed
Geng, Hua; Todd, Naomi M; Devlin-Mullin, Aine; Poologasundarampillai, Gowsihan; Kim, Taek Bo; Madi, Kamel; Cartmell, Sarah; Mitchell, Christopher A; Jones, Julian R; Lee, Peter D
2016-06-01
A correlative imaging methodology was developed to accurately quantify bone formation in the complex lattice structure of additive manufactured implants. Micro computed tomography (μCT) and histomorphometry were combined, integrating the best features from both, while demonstrating the limitations of each imaging modality. This semi-automatic methodology registered each modality using a coarse graining technique to speed the registration of 2D histology sections to high resolution 3D μCT datasets. Once registered, histomorphometric qualitative and quantitative bone descriptors were directly correlated to 3D quantitative bone descriptors, such as bone ingrowth and bone contact. The correlative imaging allowed the significant volumetric shrinkage of histology sections to be quantified for the first time (~15 %). This technique demonstrated the importance of location of the histological section, demonstrating that up to a 30 % offset can be introduced. The results were used to quantitatively demonstrate the effectiveness of 3D printed titanium lattice implants.
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Electrical Properties of Reactive Liquid Crystal Semiconductors
NASA Astrophysics Data System (ADS)
McCulloch, Iain; Coelle, Michael; Genevicius, Kristijonas; Hamilton, Rick; Heckmeier, Michael; Heeney, Martin; Kreouzis, Theo; Shkunov, Maxim; Zhang, Weimin
2008-01-01
Fabrication of display products by low cost printing technologies such as ink jet, gravure offset lithography and flexography requires solution processable semiconductors for the backplane electronics. The products will typically be of lower performance than polysilicon transistors, but comparable to amorphous silicon. A range of prototypes are under development, including rollable electrophoretic displays, active matrix liquid crystal displays (AMLCD's), and flexible organic light-emitting diode (OLED) displays. Organic semiconductors that offer both electrical performance and stability with respect to storage and operation under ambient conditions are required. This work describes the initial evaluation of reactive mesogen semiconductors, which can polymerise within mesophase temperatures, “freezing in” the order in crosslinked domains. These crosslinked domains offer mechanical stability and are inert to solvent exposure in further processing steps. Reactive mesogens containing conjugated aromatic cores, designed to facilitate charge transport and provide good oxidative stability, were prepared and their liquid crystalline properties evaluated. Both time-of-flight and field effect transistor devices were prepared and their electrical characterisation reported.
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Universal composition-structure-property maps for natural and biomimetic platelet-matrix composites and stacked heterostructures.
PubMed
Sakhavand, Navid; Shahsavari, Rouzbeh
2015-03-16
Many natural and biomimetic platelet-matrix composites--such as nacre, silk, and clay-polymer-exhibit a remarkable balance of strength, toughness and/or stiffness, which call for a universal measure to quantify this outstanding feature given the structure and material characteristics of the constituents. Analogously, there is an urgent need to quantify the mechanics of emerging electronic and photonic systems such as stacked heterostructures. Here we report the development of a unified framework to construct universal composition-structure-property diagrams that decode the interplay between various geometries and inherent material features in both platelet-matrix composites and stacked heterostructures. We study the effects of elastic and elastic-perfectly plastic matrices, overlap offset ratio and the competing mechanisms of platelet versus matrix failures. Validated by several 3D-printed specimens and a wide range of natural and synthetic materials across scales, the proposed universally valid diagrams have important implications for science-based engineering of numerous platelet-matrix composites and stacked heterostructures.
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Policy Development for Biodiversity Offsets: A Review of Offset Frameworks
NASA Astrophysics Data System (ADS)
McKenney, Bruce A.; Kiesecker, Joseph M.
2010-01-01
Biodiversity offsets seek to compensate for residual environmental impacts of planned developments after appropriate steps have been taken to avoid, minimize or restore impacts on site. Offsets are emerging as an increasingly employed mechanism for achieving net environmental benefits, with offset policies being advanced in a wide range of countries (i.e., United States, Australia, Brazil, Colombia, and South Africa). To support policy development for biodiversity offsets, we review a set of major offset policy frameworks—US wetlands mitigation, US conservation banking, EU Natura 2000, Australian offset policies in New South Wales, Victoria, and Western Australia, and Brazilian industrial and forest offsets. We compare how the frameworks define offset policy goals, approach the mitigation process, and address six key issues for implementing offsets: (1) equivalence of project impacts with offset gains; (2) location of the offset relative to the impact site; (3) “additionality” (a new contribution to conservation) and acceptable types of offsets; (4) timing of project impacts versus offset benefits; (5) offset duration and compliance; and (6) “currency” and mitigation replacement ratios. We find substantial policy commonalities that may serve as a sound basis for future development of biodiversity offsets policy. We also identify issues requiring further policy guidance, including how best to: (1) ensure conformance with the mitigation hierarchy; (2) identify the most environmentally preferable offsets within a landscape context; and (3) determine appropriate mitigation replacement ratios.
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Policy development for biodiversity offsets: a review of offset frameworks.
PubMed
McKenney, Bruce A; Kiesecker, Joseph M
2010-01-01
Biodiversity offsets seek to compensate for residual environmental impacts of planned developments after appropriate steps have been taken to avoid, minimize or restore impacts on site. Offsets are emerging as an increasingly employed mechanism for achieving net environmental benefits, with offset policies being advanced in a wide range of countries (i.e., United States, Australia, Brazil, Colombia, and South Africa). To support policy development for biodiversity offsets, we review a set of major offset policy frameworks-US wetlands mitigation, US conservation banking, EU Natura 2000, Australian offset policies in New South Wales, Victoria, and Western Australia, and Brazilian industrial and forest offsets. We compare how the frameworks define offset policy goals, approach the mitigation process, and address six key issues for implementing offsets: (1) equivalence of project impacts with offset gains; (2) location of the offset relative to the impact site; (3) "additionality" (a new contribution to conservation) and acceptable types of offsets; (4) timing of project impacts versus offset benefits; (5) offset duration and compliance; and (6) "currency" and mitigation replacement ratios. We find substantial policy commonalities that may serve as a sound basis for future development of biodiversity offsets policy. We also identify issues requiring further policy guidance, including how best to: (1) ensure conformance with the mitigation hierarchy; (2) identify the most environmentally preferable offsets within a landscape context; and (3) determine appropriate mitigation replacement ratios.
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Differential comparator cirucit
DOEpatents
Hickling, Ronald M.
1996-01-01
A differential comparator circuit for an Analog-to-Digital Converter (ADC) or other application includes a plurality of differential comparators and a plurality of offset voltage generators. Each comparator includes first and second differentially connected transistor pairs having equal and opposite voltage offsets. First and second offset control transistors are connected in series with the transistor pairs respectively. The offset voltage generators generate offset voltages corresponding to reference voltages which are compared with a differential input voltage by the comparators. Each offset voltage is applied to the offset control transistors of at least one comparator to set the overall voltage offset of the comparator to a value corresponding to the respective reference voltage. The number of offset voltage generators required in an ADC application can be reduced by a factor of approximately two by applying the offset voltage from each offset voltage generator to two comparators with opposite logical sense such that positive and negative offset voltages are produced by each offset voltage generator.