bluuebunny/crossref_metadata_2025 huggingface dataset:
Photoluminescence and Visible Diffuse-Reflection Spectroscopic Evidence of Samarium Reduction in Air-Fired Samples of Mixed Samarium: Strontium Tetraborate Precipitates
Authors: Brown Telvin M. , Jeffreys Mareo C. , Pehaire Mario , Stump Nathan A.
Published: March 2013

Photoluminescence and visible diffuse-reflection spectroscopies have provided evidence of the reduction of samarium to the divalent state in samarium-doped strontium borate and pure samarium borate samples. The samples were prepared by the air firing of homogeneous precipitates of divalent strontium and trivalent samarium ions from aqueous solutions with saturated sodium tetraborate. The use of this method in the preparation of divalent lanthanide ions has not been reported previously. Reduced samarium was observed in fired tetraborate precipitates prepared with solutions containing 1, 5, 10, 25, 50, 75, and 90 mole percent samarium versus strontium. Divalent samarium also was identified in fired precipitates of trivalent samarium solutions precipitated with tetraborate. Sm2+ was identified as the primary emitting species in each of the eight compositions. However, diffuse-reflection spectroscopy indicated the presence of trivalent samarium in the studied samples, ranging from minimal for samples prepared with low samarium concentrations to nearly exclusive when pure samarium was studied. Quenching of the characteristic emission associated with the trivalent species is believed to result in the absence of the emission features arising from residual samarium(III) in the products. Although the absence of trivalent samarium emission enhanced the ability of emission spectroscopy to identify small amounts of divalent samarium, indicating that reduction had occurred, it limited the ability of this method to determine the extent of the reduction. Diffuse-reflection spectroscopy's ability to look at both species provided a much better analysis of the extent of samarium reduction.
Structural Differences between Cold- and Melt-Crystallized Poly(trimethylene terephthalate) Samples
Authors: Chen Zhen , Yan Shouke
Published: March 2013

Time-resolved Fourier transform infrared spectroscopy was used to investigate the structural differences between cold- and melt-crystallized poly(trimethylene terephthalate) (PTT) samples. To elucidate the arrangement of different chain segments in the crystalline phase obtained through different crystallization processes, characteristic bands associated with the phenylene rings, the CH2 segments, and the C–O–C segments were followed during the cold and the melt crystallizations. The results show that the alignment of the phenylene rings and the C=O) groups in the PTT crystals produced via cold- and melt-crystallization processes are essentially the same, while the alignment of the CH2 segments depends on the crystallization condition. It was found that the CH2 segments in the melt-crystallized sample were more stable than those in the cold-crystallized sample. This was ascribed to the different crystallization environment. Melt-crystallized PTT chains have higher mobility, and the variation of flexible segments is quicker than that of the rigid segments. However, in cold crystallization, the CH2 segments are restricted by the adjacent environment in the glass state, which weakens their capability of transforming their conformation; this leads to a cooperative change of CH2 segments, phenylene rings, and C=O groups. Therefore, the stability of CH2 segments in crystalline structure is lowered accordingly.
Increasing the Quantitative Credibility of Open-Path Fourier Transform Infrared (FT-IR) Spectroscopic Data, with Focus on Several Properties of the Background Spectrum
Authors: Shao Limin , Wang Wanping , Griffiths Peter R. , Leytem April B.
Published: March 2013

The choice of the type of background spectrum affects the credibility of open-path Fourier transform infrared spectroscopy (OP/FT-IR) data, and consequently, the quality of data analysis. We systematically investigated several properties of the background spectrum. The results show that a short-path background measured with the lowest amplifier gain could significantly reduce noise in the calculated absorbance spectrum, by at least 30% in our case. We demonstrated that by using a short-path background, data analysis is more resistant to interferences such as wavenumber shift or resolution alteration that occurs as a consequence of aging hardware or misalignment. We discussed a systematic error introduced into quantitative analyses by the short-path background and developed a procedure to correct that error. With this correction approach, a short-path background established five years ago was still found to be valid. By incorporating these findings into the protocol for quantitative analysis, we processed the measurements with two OP/FT-IR instruments set up side by side in the vicinity of a large dairy farm, to monitor NH3, CH4, and N2O. The two sets of calculated concentrations showed high agreement with each other. The findings of our investigations are helpful to atmospheric monitoring practitioners of OP/FT-IR spectroscopy and could also be a reference for future amendments to the protocols outlined in the guidelines of the U.S. Environmental Protection Agency, the American Society for Testing and Materials, and the European Committee for Standardization.
Fairy tales and funhouse mirrors: Frameworks of assimilation and conformity in Extreme Makeover, The Swan and What Not To Wear
Authors: Lavigne Carlen
Published: March 2013

Numerous researchers have commented unfavourably on the classist, sexist and assimilationist nature of contemporary American makeover programs; this article examines Extreme Makeover, The Swan, and What Not To Wear in order to identify the narrative paradigms most commonly used to cloak
such conformist pressures in more socially acceptable guises. A close analysis demonstrates how frameworks such as initiation rituals, aesthetic ideals, market values, self-empowerment, and fairy tales ultimately overlap to deflect attention from feminist concerns about larger social issues
and serve to demonstrate how these pervasive cultural ideas have been reworked to serve political and commercial ends.
‘Am I the only one here who sees the alien’: Science in Invader ZIM
Authors: Gil Steven
Published: March 2013

Science Fiction (SF) articulates many of the central issues faced in culture and society and none greater than the role, capacities and implications of scientific knowledge. As a genre it displays a heightened capacity to engage in philosophical debates giving salient insights. Contemporary
scientific knowledge or 'mainstream science' provides the critical grounding on which the extraordinary worlds of SF are naturalized. However, complete adherence to known facts would render SF incapable of facilitating the speculative dimensions in which it revels. To counter-balance this,
marginal science is often engaged as a means to extend the known and explore new possibilities whilst maintaining a noticeable link to scientific rationality. Invader ZIM (Nicktoon Productions 2001-2003, 2006), an animated television (TV) series about an alien's efforts to conquer Earth and
the attempts of a young paranormal enthusiast to stop him, provides a way to articulate this positioning of science.
Negotiating Icelandic spaces in the modern global culture: Arnaldur Indridison’s Reyjkavik murder mysteries
Authors: Strahan Linda
Published: March 2013

Reykjavik police detective Erdendur's tight hold on the customs and culture of Iceland's historic past have frozen him in time. As he solves murders, the chill of death, the Icelandic cold, and the winter in his own heart combine to remind readers of loss that knows no borders. Erlendur
serves as a cautionary tale about standing still, in a blizzard or in life.
Indian movies, brand Australia and the marketing of Australian cosmopolitanism
Authors: Hassam Andrew
Published: March 2013

Indian movies shot overseas have attracted the attention of not only advertising agencies keen to see their clients’ brands appearing on-screen, but also government tourism commissions eyeing India’s growing middle classes as potential visitors. Australian federal and state
governments offer Indian film producers financial incentives to film in Australia, and Australian cities now regularly supply Indian movies with backdrops of upmarket shopping malls, stylish apartments and exclusive restaurants. Yet in helping to project the lifestyle fantasies of India’s
new middle classes, Australian government agencies are supporting an Indian view of Australia. While this image may attract Indian tourists to Australia, it presumes Australia is culturally White and British, and as a result Australian agencies market an Australian cosmopolitanism defined
not in terms of cultural diversity but in terms of the availability of global brands. The absence of cultural diversity in how Australia is branded in Indian movies is at heart a political rather than a marketing issue and one that can be challenged effectively only by holding to account those
who are politically responsible for branding the nation.
An alienated mind dreaming for integration: Constrained cosmopolitanism in Wumingshi’s ‘Modern Literati Novel’
Authors: Xiaoping Wang
Published: March 2013

Mainstream scholarship on Wumingshi – a marginal figure in modern Chinese literary history, but a very popular writer in the 1940s – interprets his writings as ‘neo-romanticism’, ‘late romanticism’ or ‘popular modernism’. This study, through
the practice of political hermeneutics, contends that his works are in fact an example of ‘modern literati fiction’ or ‘fiction of ideas’ – a sort of middlebrow fiction for the popular culture market of modern China.
Ivy fashion, folk music and the Japanese perception of American college culture in the 1960s
Authors: Tachi Mikiko
Published: March 2013

This article examines the popularity of Ivy fashion in Japan in the 1960s to analyse the ways in which Japanese businesses and consumers domesticated American culture. Ivy fashion, together with folk music, represented the idyllic American college life and the affluence of American
society, while at the same time, marked the rapid economic growth of Japan and the youth and optimism of Japanese baby boomers. Businesses that promoted Ivy fashion idealized Ivy League students, identifying them both as the privileged elite Americans as well as the appropriate role models
for young Japanese men. Consumption of Ivy fashion provided young men who lacked role models domestically with a means to define a generational and gender identity by misappropriating American culture.
Turning the gun on America: Cobra and the action film as cultural critique
Authors: Mattes Ari
Published: March 2013

It is widely acknowledged that the action film has been one of Hollywood’s most successful products over the last three decades or so. However, many commentators, both popular and academic, continue to marginalize or dismiss the value of the action film as a critical, socially
conscious, and aesthetically potent artefact. Scholarship that has approached the action film has tended to be based upon readings of gender and political ideology. Aesthetic readings of 1980s action films (the decade when the genre was at its peak), such as Eric Lichtenfeld’s Action
Speaks Louder (2004), have tended to be dismissive of the films as examples of propagandistic, exceedingly patriotic ‘Reaganite entertainments’. It is the intention of this article, through a close analysis of George P. Cosmatos’ 1986 film Cobra, to demonstrate that –
rather than simply a piece of replicatory right-wing propaganda – the 1980s action film (and action cinema in general) challenges the notions of American political identity, patriotism and heroism upon which it is founded, thereby opening the way for a deeper critical understanding of
American cultural and mythical impulses at large.
Modern Arab uprisings and social media: An historical perspective on media and revolution
Authors: Mellen Roger P.
Published: March 2013

Journalists and other observers claim that new social media brought about the wave of current popular uprisings in the Middle East. This article examines – with an historical perspective within the intellectual framework of media ecology – this idea of new media as the cause
of revolution. It concludes that while new media are an important factor behind these recent revolts, they do not cause revolution. Shifts in communication technology have a major influence on the way we interrelate and organize our society. The very structure of the World Wide Web makes control
of information extremely difficult for autocratic governments and is indeed a strong force for popular movements, democratic change and freedom.
Ecological journalism and the role of perception
Authors: Tracy Christine M.
Published: March 2013

Perceptions of the news most often lack critical awareness and are steered by technology away from a more self-reflective consciousness. Is technology the problem or has it exacerbated a general human tendency to seek out ideas that reinforce what we already believe? This analysis uses
media ecology theories and recent cognitive, media and political science research to better understand why it is so hard to foster a collective dialogue despite the development of sophisticated communication technology. Most journalism is not effective in bridging the increasing polarization
of the news and information environment, in part because most audiences are not challenged to question their existing beliefs in a safe, accessible and understandable way; instead, they use facts to confirm their already existing values and knowledge. Viewing news as an ecology, which is integral
to this argument, places responsibility for the quality of news with consumers as well as producers (journalists) and recognizes that both are capable of manipulation. In addition to developing new forms of news, the author calls for a closer look at the perceptual processing of news and information
and a more self-reflective, integral style of both the consumption and production of news – a true ecology.
Why I am not going to teach public speaking online
Authors: Hunt III Arthur W.
Published: March 2013

My reasons for refusing to teach public speaking online include the following: First, the way I currently teach public speaking seems to work very well. Actually, from my understanding of the history of rhetoric it has worked well for thousands of years. The second reason concerns my
vocational calling. My perception of effective teaching involves being with students in real physical space. In other words, I am called to the classroom, not the computer screen. My third reason – not unrelated to the first two – concerns the notion of embodiment. I am persuaded
that embodied teaching, especially with a subject that centers on the use of the body and voice, is superior to disembodied teaching. My reason for not wanting to teach public speaking online would be identical to why I do not think sculpting or tennis should be taught online.
Stealing the moment: The non-narrative fashion films of Ruth Hogben and Gareth Pugh
Authors: Khan Nathalie
Published: March 2013

Fashion films, which take the place of the catwalk show, break with the actual and virtual perception of fashion. The catwalk show’s predominant purpose is to present the clothes on display, to present the material object in time and space. By breaking with this tradition, by
replacing the live event with the projection of a digital film, we alter the experience, as well as the reality of the garment. This article seeks to explore the role and function of non-narrative fashion film in relation to the collaboration between Ruth Hogben and Gareth Pugh. The aim is
to establish an ontological study of the aesthetic nature of non-narrative fashion film.
‘High Fashion Crime Scenes’: Recent trends in fashion imagery, a legacy of film noir
Authors: Cecil Anne
Published: March 2013

Roland Barthes suggested that photographs are, essentially, about death. This article traces the relationship between crime scene photographs of the 1930s and 1940s, the visual aesthetic of film noir and a resurgence of the genre in high fashion photography. From the bruised-eyed runway
models of Comme de Garçons in the 1980s to the preoccupation with death, trauma, alienation and decay in the work and promotions of Vivienne Westwood, John Galliano, Alexander McQueen, Hussein Chalayan and Victor & Rolf throughout the 1990s, this trend has grown stronger in the
new millennium, as seen in campaigns by leading fashion photographers, both in editorial and in advertising for luxury brands. LA photographer Melanie Pullen continues to explore these themes in her ongoing work ‘High Fashion Crime Scenes’. Drawing on Weegee’s Noir explorations
of urban life and films such as Irvin Kershner’s 1978 film, The Eyes of Laura Mars, Pullen uses fashion as a symbol of the deceased’s everyday life, the mundane juxtaposed with the catastrophic. This imagery probes the unions between beauty and brutality, artifice and alienation,
glamour and gore. Drawing on the seminal work of John Berger on photographic advertising in Ways of Seeing (1972), Jennifer L. Pozner’s work within the media, and Caroline Evans’ influential text Fashion at the Edge: Spectacle, Deathliness and Modernity of 2007, this article will
attempt to unravel the relationship between high fashion and violent death within contemporary visual culture.
Tabloid TV in Zambia: A reception study of Lusaka viewers of Muvi TV news
Authors: Wasserman Herman , Mbatha Loisa
Published: March 2013

The tabloid news genre has been chastized for depoliticizing its public by causing cynicism about the democratic process and lowering the standards of rational public discourse. Counter-arguments point to the alternative public sphere offered by popular media such as ‘tabloid
TV’ which is the focus of this study. The ‘tabloid TV’ genre is relatively new in Zambia and in the African context in general. This article sets out to examine the rapid rise in popularity of the Zambian private television station, Muvi TV. It examines Muvi TV’s main
evening news as an example of the ‘tabloid TV’ news genre vis-à-vis the criticisms levelled against tabloidization. The article presents results from a reception study of viewers in the capital city, Lusaka. A three-stage qualitative study was carried out, consisting of
a thematic/content analysis of news bulletins, focus groups and individual, semi-structured interviews. The findings suggest that audiences attach greater credibility to Muvi TV’s news broadcasts than those of the public broadcaster, the Zambia National Broadcasting Corporation (ZNBC).
As such, Muvi TV can be seen to fulfil a political function despite its sensationalized approach.
CONFERENCE REPORT
Authors: Tomaselli Keyan G.
Published: March 2013

BEYOND ENCODING/DECODING: ZOMBIES, WITCHCRAFT AND STAMMERING NORMATIVE THEORY

BEYOND NORMATIVE APPROACHES: EVERYDAY MEDIA CULTURE IN AFRICA, UNIVERSITY OF THE WITWATERSRAND, THE UNIVERSITY OF MICHIGAN AND THE UNIVERSITY OF WESTMINSTER, JOHANNESBURG, SOUTH AFRICA, 27–29 FEBRUARY
2012
The Nigerian press and the challenge of private newspaper ownership: A study of the Nigerian Tribune, 1949–2009
Authors: Adesoji Abimbola Omotayo , Alimi Shina
Published: March 2013

Beyond playing its major role of informing, educating and entertaining, the press in different contexts, cultures and dispensations remains a major propaganda tool, and hence its use and abuse by proprietors, political and government elites, and people of influence in society. The clamour
to establish and sustain a newspaper or a chain of publications becomes understandable even when the challenges are great. Whereas the desire to promote vibrant nationalism, challenge autocracy in different forms, or pursue a cause that the proprietor strongly believes in could be central
to the founding of a newspaper, the use to which it is put – which oftentimes could be the hidden motive for its establishment or a manifestation of the derailment of the original purposes – has provoked interest in probing the motives for newspaper ownership. As the oldest surviving
privately owned newspaper in Nigeria, the Nigerian Tribune (NT) provides a classic example of how newspapers come to serve a common cause while at the same time projecting the personal ambitions and interests of their founders. This article examines the challenges of private newspaper ownership
in Nigeria using the NT as a case study. The article is situated within the context of theories on the political economy of media with emphasis on the propaganda model. It argues that in spite of NT’s contribution to the nationalist struggle and the process of nation-building, the newspaper
was a potent political weapon in the hands of its owner. The use to which it was put by the successor-owner lends further credence to this claim. The article concludes that among other factors, a combination of dynamism and ideologically driven partisanship is needed to sustain newspapers
and improve their effectiveness.
The media and democratic consolidation in Nigeria: An overview of government–media relations, 1999–2009
Authors: Alozieuwa Simeon H. O.
Published: March 2013

Relations between the media and government in Nigeria have historically been conflictual. Nevertheless, the Nigerian media has played important roles in the country’s struggles to free itself from the shackles of colonialism and military rule. A national desire for disengagement
from decades of military dictatorship, however, took away the usually critical edge of the Nigerian media once the democratic dispensation got underway. But as the post-transition euphoria gave way to realism, government and media relapsed into their old animosity. This article argues that
the initial indifference to certain undemocratic tendencies – especially of the Obasanjo administration in the name of not ‘rocking the boat’ of the new-found democracy – did set a new ambience, resulting in government becoming too sensitive to criticism. The article
posits that the initial ambivalence of the media towards the government could have inflicted more harm on the democratic project than good, and was responsible for the manner in which the government responded by the time it regained its critical edge. It contends that the media should at all
times remain faithful to its watchdog role, hereby assisting in strengthening the country’s democracy.
Plattformstrategien für altes und neues Wissen
Authors: Sternitzke Nicolai
Published: March 2013

Digitale Informationsdienstleistungen und elektronische Publikationsangebote sind in den letzten Jahren zum elementaren Bestandteil der wissenschaftlichen Literaturversorgung in der internationalen Bibliothekslandschaft geworden. Durch den technologischen Wandel und die daraus resultierenden Nutzeranforderungen verfolgen auch Archive und museale Einrichtungen zunehmend den Anspruch, ihre einzigartigen Sammlungsbestände und forschungsrelevantes Schrifttum im Sinne des Open Access digital zu veröffentlichen und damit einen zeit- und ortsunabhängigen Online-Zugriff auf die Materialien zu gewährleisten. Dabei spielen Nutzerorientierung, Funktionalität und Effizienz der Digitalisierungs- und Erschließungsprozesse eine ebenso tragende Rolle wie konservatorische Überlegungen zum Schutz und zur Langzeitsicherung des kulturellen Erbes. Die von der Wienbibliothek im Rathaus veranstaltete Fachkonferenz zur Digitalisierung bot zu diesem Themenspektrum facettenreiche Fachvorträge und Projektberichte aus der Anwenderperspektive verschiedener Informationseinrichtungen Österreichs, der Schweiz und Deutschlands, die im Folgenden zusammenfassend dargestellt werden.
A Hands-on Approach to Teaching Protein Translation & Translocation into the ER
Authors: LaBonte Michelle L.
Published: March 2013

The process of protein translation and translocation into the endoplasmic reticulum (ER) can often be challenging for introductory college biology students to visualize. To help them understand how proteins become oriented in the ER membrane, I developed a hands-on activity in which students use Play-Doh to simulate the process of protein insertion into the ER membrane. After completing the hands-on activity, students are better able to solve problems in which they have to predict the membrane orientation of a protein.
Producing & Consuming Processed Foods: A Critical-Thinking Exercise
Authors: Ruane Lauren G. , Ruane Daniel M.
Published: March 2013

The goal of this interdisciplinary activity is to encourage students to think critically about the ethical, environmental, and human health consequences of producing and consuming processed foods.
To Build an Ecosystem: An Introductory Lab for Environmental Science & Biology Students
Authors: Hudon Daniel , Finnerty John R.
Published: March 2013

A hypothesis-driven laboratory is described that introduces students to the complexities of ecosystem function. Students work with live algae, brine shrimp, and sea anemones to test hypotheses regarding the trophic interactions among species, the exchange of nutrients and gases, and the optimal ratio of producers to consumers and predators in enclosed, artificial-seawater ecosystems. In the initial iteration of the activity, multiple ecosystems that differ in their composition of organisms are assembled according to simple recipes by individual students or small lab groups. Two weeks later, the ecosystems are deconstructed, and the students tally the organisms and assess key water-quality measures, including salinity, pH, and ammonia levels. Some sample data and results are presented, as well as tips for successful implementation.
Intragenomic Conflict Between the Two Major Knob Repeats of Maize
Authors: Kanizay Lisa B , Albert Patrice S , Birchler James A , Dawe R Kelly
Published: March 2013

Examples of meiotic drive, the non-Mendelian segregation of a specific genomic region, have been identified in several eukaryotic species. Maize contains the abnormal chromosome 10 (Ab10) drive system that transforms typically inert heterochromatic knobs into centromere-like domains (neocentromeres) that move rapidly poleward along the spindle during meiosis. Knobs can be made of two different tandem repeat sequences (TR-1 and 180-bp repeat), and both repeats have become widespread in Zea species. Here we describe detailed studies of a large knob on chromosome 10 called K10L2. We show that the knob is composed entirely of the TR-1 repeat and is linked to a strong activator of TR-1 neocentromere activity. K10L2 shows weak meiotic drive when paired with N10 but significantly reduces the meiotic drive exhibited by Ab10 (types I or II) in Ab10/K10L2 heterozygotes. These and other data confirm that (1) there are two separate and independent neocentromere activities in maize, (2) that both the TR-1 and knob 180 repeats exhibit meiotic drive (in the presence of other drive genes), and (3) that the two repeats can operate in competition with each other. Our results support the general concept that tandem repeat arrays can engage in arms-race-like struggles and proliferate as an outcome.
Identifying Loci Under Selection Against Gene Flow in Isolation-with-Migration Models
Authors: Sousa Vitor C , Carneiro Miguel , Ferrand Nuno , Hey Jody
Published: March 2013

When divergence occurs in the presence of gene flow, there can arise an interesting dynamic in which selection against gene flow, at sites associated with population-specific adaptations or genetic incompatibilities, can cause net gene flow to vary across the genome. Loci linked to sites under selection may experience reduced gene flow and may experience genetic bottlenecks by the action of nearby selective sweeps. Data from histories such as these may be poorly fitted by conventional neutral model approaches to demographic inference, which treat all loci as equally subject to forces of genetic drift and gene flow. To allow for demographic inference in the face of such histories, as well as the identification of loci affected by selection, we developed an isolation-with-migration model that explicitly provides for variation among genomic regions in migration rates and/or rates of genetic drift. The method allows for loci to fall into any of multiple groups, each characterized by a different set of parameters, thus relaxing the assumption that all loci share the same demography. By grouping loci, the method can be applied to data with multiple loci and still have tractable dimensionality and statistical power. We studied the performance of the method using simulated data, and we applied the method to study the divergence of two subspecies of European rabbits (Oryctolagus cuniculus).
Effects of Genetic Drift and Gene Flow on the Selective Maintenance of Genetic Variation
Authors: Star Bastiaan , Spencer Hamish G
Published: March 2013

Explanations for the genetic variation ubiquitous in natural populations are often classified by the population–genetic processes they emphasize: natural selection or mutation and genetic drift. Here we investigate models that incorporate all three processes in a spatially structured population, using what we call a construction approach, simulating finite populations under selection that are bombarded with a steady stream of novel mutations. As expected, the amount of genetic variation compared to previous models that ignored the stochastic effects of drift was reduced, especially for smaller populations and when spatial structure was most profound. By contrast, however, for higher levels of gene flow and larger population sizes, the amount of genetic variation found after many generations was greater than that in simulations without drift. This increased amount of genetic variation is due to the introduction of slightly deleterious alleles by genetic drift and this process is more efficient when migration load is higher. The incorporation of genetic drift also selects for fitness sets that exhibit allele-frequency equilibria with larger domains of attraction: they are “more stable.” Moreover, the finiteness of populations strongly influences levels of local adaptation, selection strength, and the proportion of allele-frequency vectors that can be distinguished from the neutral expectation.
Improved Switching Response of VO2 Devices Deposited on Silicon Nitride Membranes
Authors: Wang Yan , Muth John F.
Published: March 2013

VO2films were deposited on sapphire, ITO glass and 200 nm thick silicon nitride membranes by Pulsed Laser Deposition (PLD). The electrical and optical properties have been investigated. Joule heating devices fabricated on silicon nitride membranes switches from semiconductor phase to metal phase by applying a constant voltage across two metal contacts. Compared to the devices fabricated on the normal substrates, such as sapphire, silicon or glasses, the switching speed of the devices on membrane is an order of magnitude faster. Decreasing the area and thickness of VO2 on top of thinner membranes allows kHz bandwidth to be achieved.
Magnetic Interactions Study in ZnO Doped with Fe Ions Produced by Thermal Diffusion Processes
Authors: Baca R. , Galván M. , Méndez J. V. , Andraca J. A. , Peña R.
Published: March 2013

Recently, the oxides have received attention and great interest due to their magnetic ordering above of the room temperature by doping a very low amount of transition metal ions, which are very promising for applications such as biosensing, hyperthermia, doped magnetic semiconductors with lower energy losses and rapid response at alternating-magnetic fields. In this work the magnetic interactions on Fe doped ZnO thin-films was studied. Raman spectroscopy allowed the monitoring of iron ions diffusion and demonstrated that symmetry modes are crucial for understanding of the magnetic ordering. X-ray diffraction (XRD) was used to determine the oxidation state of the iron ions and stress into ZnO lattice. MFM confirmed that magnetic moments and magnetic forces on scanned surface depend on magnetic-domain structure formation.
The Use of High Durability Alumino-Borosilicate Glass for the Encapsulation of High Temperature Reactor (HTR) Fuel
Authors: Heath Paul G. , Stennett Martin C. , McGann Owen J. , Hand Russell J. , Hyatt Neil C.
Published: March 2013

The development of suitable waste forms for waste produced by generation IV reactors is of critical concern for future operations. To date no accepted disposal route for Tri-Structural Isotropic (TRISO) High Temperature Reactor (HTR) fuel exists. Alumino-borosilicate glass has been studied for its ability to encapsulate TRISO particle fuels. This glass was selected for its high aqueous durability. Encapsulation was achieved by cold pressing and sintering of glass powders mixed with HTR fuel. Sintering profiles capable of eliminating interconnected porosity in the composites were developed. The chemical compatibility and wetting of the glass matrix with the fuel were analysed along with the aqueous durability of the sintered glass matrix. Composites sintered under a controlled atmosphere produced unfractured monoliths with minimal chemical interaction between the glass and the TRISO particles. The Product Consistency Test (PCT) durability assessment indicated the sintered alumino-borosilicate glass was approximately an order of magnitude more durable than an equivalent R7T7 borosilicate glass. These results suggest sintered alumino-borosilicate glass-TRISO particle composites may provide a potential disposal route for spent TRISO particle fuel.
Compressive Fracture Behavior of Bi-added Ni50Mn28Ga22 Ferromagnetic Shape Memory Alloys
Authors: Tanimura Hirotaka , Tahara Masaki , Inamura Tomonari , Hosoda Hideki
Published: March 2013

In order to develop NiMnGa/polymer composite materials, a production of single-crystal-like NiMnGa particles is important and should be developed for better quality. Although mechanical pulverization is a promising method by utilizing intrinsic intergranular brittleness of NiMnGa polycrystalline ingots, the amount of lattice defects introduced during mechanical crushing needs to be minimized. This must be achieved by enhancement of intergranular brittleness of NiMnGa particles. In this study, the effect of Bi addition on the compressive fracture behavior of polycrystalline Ni50Mn28Ga22 was investigated where Bi was expected to be segregated to the grain boundaries in NiMnGa, similar to Bi segregation to the grain boundaries in Ni. It was found that only intergranular fracture was observed in Ni50Mn28Ga22 polycrystals with 0.3 at.% Bi addition, although a mixture of intergranular and transgranular fracture was observed in Bi-free Ni50Mn28Ga22 polycrystal. Microalloying of Bi into NiMnGa enhances intergranular embrittlement. A number of spherical particles of Bi were confirmed on the fractured surface of Bi-doped NiMnGa polycrystals. The formation of Bi particles is a proof of the grain boundary segregation of Bi in NiMnGa.
Expanded Thermochromic Color Changes in VO2 Thin Film Devices Using Structured Plasmonic Metal Layers
Authors: Wang Yan , Muth John F.
Published: March 2013

We investigate metallic thin films on VO2 and show that the magnitude of the reflected color change in that visible portion of the spectrum as VO2 undergoes the insulating to metallic phase transition can be controlled by changing the type of metal, the thickness of the metal and by patterning the metal at the nano scale. We consider the role of surface plasmas in the metal film and show that in the near infrared, the magnitude of the reflectivity increase for metal coated VO2 films, but decrease for uncoated VO2 thin films. This is explained in the context of Fresnel equations and considering the large change in the imaginary part of the dielectric constant as the VO2 changes state from the insulating to metallic phase.
AN ENZYMATIC METHOD TO OBTAIN A NEW SCAFFOLD FOR ENGINEERING CARTILAGE
Authors: Giraldo Gomez David M. , Villegas Alvarez Fernando , Garciadiego Cazares David , Sotres Vega Avelina , Piña Barba Maria C.
Published: March 2013

The purpose of this study was to achieve a descellularized scaffold from cartilage tissue, which can be used as xenograft for cartilage tissue regeneration.

This work presents the results obtained using one method to wash porcine trachea in order to remove cellular material from the extracellular matrix and to avoid the immune reaction using enzymatic detergent and partial enzymatic degradation with Deoxyribonuclease I (DNase-I), Ethylenediaminetetraacetic Acid (EDTA) and Trypsin. This treatment was qualitatively evaluated by Scanning Electron Microscopy (SEM), and H&E Stain (Histology), and quantitatively evaluated by DNA quantification. The thermal characterization of the descellularized scaffold was carried out using Termogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). The type of collagen obtained from the scaffold was determined through SDS-PAGE electrophoresis. When using Enzymatic Treatment (ET) to wash trachea tissue, it is possible to obtain an acellular xenograft; this procedure has the potential to avoid rejection reactions of the xenograft.
Decontamination of Molten Salt Wastes for Pyrochemical Reprocessing of Nuclear Fuels
Authors: Stennett Martin C. , Hand Matthew L. , Hyatt Neil C.
Published: March 2013

Pyrochemical reprocessing of nuclear fuels, in which electrochemical separation of actinides and fission products is mediated by a molten alkali chloride salt (typically a LiCl-KCl eutectic) is of interest for future nuclear energy cycles. A key challenge in the management of pyrochemical reprocessing wastes is decontamination and recycling of the molten salt medium to remove entrained actinides and radioactive lanthanide fission products. Since pyrochlore oxides are promising candidates for the immobilisation of lanthanides and actinides, we sought to use the “problematic” molten salt to our advantage as a reaction medium for low temperature synthesis of titanate pyrochlores. Through control of reaction time and temperature, we demonstrated the synthesis of lanthanide pyrochlores at temperatures as low as 700 °C in 1 h, compared to 1350 °C in 36 h for conventional solid state synthesis. The importance of this study is in demonstrating the potential feasibility for decontamination of pyrochemical reprocessing wastes by simple addition of TiO2 to form lanthanide and actinide pyrochlores by rapid molten salt assisted reaction at moderate temperature.
Sperm Performance Better on Diamond than on Polystyrene
Authors: Sommer Andrei P. , Zhu Dan , Gagsteiger Friedrich , Fecht Hans-Jörg
Published: March 2013

Recently we postulated that polystyrene Petri dishes become soft when in contact with an aqueous milieu. Specifically, we assumed that the effect is restricted to a superficial nanolayer, a condition presumably favoring the establishment of a stable nanolayer of reactive oxygen species (ROS) at the liquid/solid-interface. Cells are known to be hypersensitive to ROS. Previously we used P19 mouse embryonal carcinoma cells and systematically analyzed their capability to climb different substrates placed vertically into a Petri dish. The worst and best performance was found on polystyrene (Petri dish material) and nanocrystalline diamond, respectively. Polystyrene Petri dishes are today standard in laboratories conducting in vitro fertilization (IVF). Here we proceed and extend the investigation to human spermatozoa and show that their performance (vitality) on polystyrene Petri dishes is low compared to that on diamond Petri dishes. This work may propel further research and inspire the development of a new generation of cell-friendly Petri dishes.
Comparison of multi-crystalline silicon PV modules’ performance under augmented solar irradiation
Authors: Hu Yang , Hollingshead Dave , Hossain Mohammad A. , Schuetz Mark , French Roger
Published: March 2013

In developing photovoltaic (PV) systems with reliable lifetime performances, it is critical to have quantitative knowledge of not just initial properties and performances, but also their performance over the warrantied 25 year lifetime. In 2010, the Science for Energy Technology Workshop, convened by U.S Department of Energy (DOE) Basic Energy Science, prioritized photovoltaic module lifetime and degradation science (L&DS), which serve as the basis for quantitative and mechanistic understanding of lifetime performance. In order to better understand degradation rates and mechanisms of PV systems in the real-world environment, the SDLE SunFarm at Case Western Reserve University has been created, which is a highly instrumented outdoor test facility with 148 PV modules and > 8000 samples on sun for weathering and degradation studies of materials components and systems designed for long-lived energy systems. I-V and power performance of 10 multi-crystalline silicon PV modules from different manufacturers, using baseline and continuous power monitoring and comprehensive weather and solar resource monitoring, to enable time series analysis for insights into performance characteristics and initial degradation.

Five modules from each manufacturer were exposed using mirror augmentation in typical (Cleveland, OH) climatic conditions. The mirror augmentation used geometric concentration factors of 1X, 1.5X and 1.9X of the nominal 1 sun. The effect of mirror augmentation on the modules' performance is reported. A Daystar multi-tracer was used to measure I-V curves of individual modules every 15 minutes while power output under maximum power point tracking was monitored continuously. Monitoring environmental factors (wind speed, wind direction, rainfall, and humidity), solar resource, and module temperatures allow for determination of the effects of these conditions on module power production. Power data was corrected to standard test condition (STC) according to climatic and solar irradiance. Changes in fill factor, short circuit current, open circuit voltage and maximum power are reported for each module. With time series analysis, a better understanding of the module's performance over time and under environmental conditions can be developed.
Transparent Platinum Counter Electrode for Building Integrated Dye-Sensitized Solar Cells
Authors: Iefanova Anastasiia , Baroughi Mahdi Farrokh , Davoux Daren , Gautam Umesh , Dachhepati Dilip , Nepal Jeevan
Published: March 2013

A new type of counter-electrode based on platinum (Pt) nanoclusters has been introduced for semi-transparent dye-sensitized solar cells (DSSCs). This electrode is fabricated using a drop coating method where Pt nanoparticles dispersed in an acetone solvent are applied on a heated indium tin oxide (ITO) coated glass substrate. Scanning Electron Microscope (SEM) and Atomic Force Microscope (AFM) images suggest that the Pt nanoparticles form a nanoporous structure with a large surface area while the distribution of Pt appears to be uniform on the surface of the ITO layer. UV/visible/near infrared transmittance spectroscopy showed that the Pt/ITO/glass electrode is highly transparent with a maximum transparency of 80% at 550 nm.
Laser Scribing of W-textured ZnO Substrates Using Green Laser
Authors: Ishikawa Ryousuke , Wada Hidetoshi , Kurokawa Yasuyoshi , Sichanugrist Porponth , Konagai Makoto
Published: March 2013

Thin-film silicon solar cells have been attracted a lot of intention as low-cost solar cells. One of the most important technologies for improving their performances is light trapping. We have demonstrated the high potential of double-textured zinc oxide (ZnO) thin films used as front transparent conductive oxide (TCO) films due to further enhancement of their light-trapping effects. Although the laser scribing method has already been well established for low-cost thin-film silicon solar cell module manufacturing, laser scribing technique on double-textured ZnO is new and still a challenging issue. In this study, we firstly demonstrated the availability of laser scribing for amorphous silicon (a-Si) solar cells fabricated on double-textured ZnO substrates. It is general to utilize lasers with wavelength of 1.06 μm and 532 nm for scribing of TCO and silicon layer, respectively. Here we attempted to scribe both of TCO and silicon layers using a 532 nm wavelength laser (green laser) for process simplifying.
Growth of SnS van der Waals Epitaxies on Layered Substrates
Authors: Wang S.F. , Fong W.K. , Wang W. , Leung K.K. , Surya C.
Published: March 2013

In this paper we present systematic investigations on the growth of SnS van der Waals epitaxies (vdWEs) on different substrates, including crystalline and layered substrates, by molecular beam epitaxy (MBE). Experimental growth of SnS on conventional 3D substrates, such as GaAs, indicates strong interaction between the SnS layer and the substrate resulting in poor crystallinity in general. Substantial improvement in the film crystallinity can be obtained when the deposition is made on layered substrates, with saturated surface bonds, as observed in SnS films deposited on mica and crystalline substrates with a graphene buffer layer. Crystal size as large as one micron and rocking curve FWHM of 0.118° was observed despite the large lattice mismatches. This represents significant improvement over the reported value of ∼3°. Several symmetric growth orientations are observed for films grown on mica substrates. The results indicate that weak vdW interactions between the saturated bonds of the substrate surface and the SnS unit layer which is an important factor for achieving high quality epitaxy layered materials.
Simulating Constant Current STM Images of the Rutile TiO2 (110) Surface for Applications in Solar Water Splitting
Authors: Sanches F. F. , Mallia G. , Harrison N. M.
Published: March 2013

Solar water splitting has shown promise as a source of environmentally friendly hydrogen fuel. Understanding the interactions between semiconductor surfaces and water is essential to improve conversion efficiencies of water splitting systems. TiO2 has been widely adopted as a reference material and rutile surfaces have been studied experimentally and theoretically. Scanning Tunneling Microscopy (STM) is commonly used to study surfaces, as it probes the atomic and electronic structure of the surface layer. A systematic and transferable method to simulate constant current STM images using local atomic basis set methods is reported. This consists of adding more diffuse p and d functions to the basis sets of surface O and Ti atoms, in order to describe the long range tails of the conduction and valence bands (and, thus, the vacuum above the surface). The rutile TiO2 (110) surface is considered as a case study.
Room Temperature Ferromagnetism and Band Gap Investigations in Mg Doped ZnO RF/DC Sputtered Films
Authors: Mahadeva Sreekanth K. , Quan Zhi-Yong , Fan J. C. , Albargi Hasan B , Gehring Gillian A , Riazanova Anastasia , Belova L. , Rao K. V.
Published: March 2013

Mg@ZnO thin films were prepared by DC/RF magnetron co-sputtering in (N2+O2) ambient conditions using metallic Mg and Zn targets. We present a comprehensive study of the effects of film thickness, variation of O2 content in the working gas and annealing temperature on the structural, optical and magnetic properties. The band gap energy of the films is found to increase from 4.1 to 4.24 eV with the increase of O2 partial pressures from 5 to 20 % in the working gas. The films are found to be ferromagnetic at room temperature and the saturation magnetization increases initially with the film’s thickness reaching a maximum value of 14.6 emu/cm3 and then decreases to finally become diamagnetic beyond 95 nm thickness. Intrinsic strain seems to play an important role in the observed structural and magnetic properties of the Mg@ZnO films. On annealing, the as-obtained ‘mostly amorphous’ films in the temperature range 600 to 800°C become more crystalline and consequently the saturation magnetization values reduce.