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Sample records for gender glasses theoretical

  1. Speaking of Gender Identity: Theoretical Approaches.

    ERIC Educational Resources Information Center

    Freedman, Susan A.

    Various definitions of gender identity have ranged from recognition of one's biological sex to an individual's sense of masculinity or femininity. For the purpose of this paper, which examines some of the theoretical approaches to the subject, gender identity will be defined as "the degree to which individuals are 'aware' of and accept their…

  2. Filling the Glass: Gender Perspectives on Families

    ERIC Educational Resources Information Center

    Ferree, Myra Marx

    2010-01-01

    The challenge feminist scholarship posed to family studies has been largely met through the incorporation of research on gender dynamics within families and intersectional differences among them. Despite growing attention to gender as performance and power in more diverse families, the more difficult work of understanding the dynamics of change…

  3. Filling the Glass: Gender Perspectives on Families

    ERIC Educational Resources Information Center

    Ferree, Myra Marx

    2010-01-01

    The challenge feminist scholarship posed to family studies has been largely met through the incorporation of research on gender dynamics within families and intersectional differences among them. Despite growing attention to gender as performance and power in more diverse families, the more difficult work of understanding the dynamics of change…

  4. Triggering the Gender Schema: A Theoretical Proposition.

    ERIC Educational Resources Information Center

    Freedman, Susan A.

    This paper explores the relationship between the gender schema and sex typing. Drawing on previous research and personal experience, the suggestion is made that the two are distinct and separate, not necessarily co-occurring. It is further suggested that it is possible to activate the gender schema situationally. This will affect women of…

  5. Gender and Physics: a Theoretical Analysis

    NASA Astrophysics Data System (ADS)

    Rolin, Kristina

    This article argues that the objections raised by Koertge (1998), Gross and Levitt (1994), and Weinberg (1996) against feminist scholarship on gender and physics are unwarranted. The objections are that feminist science studies perpetuate gender stereotypes, are irrelevant to the content of physics, or promote epistemic relativism. In the first part of this article I argue that the concept of gender, as it has been developed in feminist theory, is a key to understanding why the first objection is misguided. Instead of reinforcing gender stereotypes, feminist science studies scholars can formulate empirically testable hypotheses regarding local and contested beliefs about gender. In the second part of this article I argue that a social analysis of scientific knowledge is a key to understanding why the second and the third objections are misguided. The concept of gender is relevant for understanding the social practice of physics, and the social practice of physics can be of epistemic importance. Instead of advancing epistemic relativism, feminist science studies scholars can make important contributions to a subfield of philosophy called social epistemology.

  6. Demystifying Gender Differences in Mentoring: Theoretical Perspectives and Challenges for Future Research on Gender and Mentoring

    ERIC Educational Resources Information Center

    Young, Angela M.; Cady, Steven; Foxon, Marguerite J.

    2006-01-01

    Issues of gender and mentoring are explored through several theoretical lenses--similarity-attraction paradigm, power dependence, social exchange, biological, and psychological theories--to provide a more comprehensive view of mentoring from a gender-based perspective. Issues related to gender and mentoring presented in past mentoring research and…

  7. Demystifying Gender Differences in Mentoring: Theoretical Perspectives and Challenges for Future Research on Gender and Mentoring

    ERIC Educational Resources Information Center

    Young, Angela M.; Cady, Steven; Foxon, Marguerite J.

    2006-01-01

    Issues of gender and mentoring are explored through several theoretical lenses--similarity-attraction paradigm, power dependence, social exchange, biological, and psychological theories--to provide a more comprehensive view of mentoring from a gender-based perspective. Issues related to gender and mentoring presented in past mentoring research and…

  8. Gender and Physics: A Theoretical Analysis.

    ERIC Educational Resources Information Center

    Rolin, Kristina

    2001-01-01

    Argues that objections raised by Koertge, Gross and Levitt, and Weinberg against feminist scholarship are unwarranted. The concept of gender, as it has been developed in feminist theory, is key to understanding why the first objection is misguided. Social analysis of scientific knowledge is key to understanding why the second and third objections…

  9. Bending gender, ending gender: theoretical foundations for social work practice with the transgender community.

    PubMed

    Burdge, Barb J

    2007-07-01

    Gender is a ubiquitous social construct that wields power over every individual in our society. The traditional dichotomous gender paradigm is oppressive, especially for transgendered people whose sense of themselves as gendered people is incongruent with the gender they were assigned at birth. Transgendered individuals are targeted for mistreatment when others attempt to enforce conventional gender boundaries. This article discusses gender-based oppression and the resulting psychosocial difficulties experienced by many transgendered individuals. The discussion advances a critical analysis of the dominant gender paradigm using two alternative theoretical perspectives on gender--queer theory and social constructionism. The article argues that the transgender community is an at-risk population and that empowering practice with this population calls on social workers to target society's traditional gender dichotomy for change. An overview of practice implications and research needs is provided.

  10. Theoretical framework for the viscosity equation for strong glasses

    NASA Astrophysics Data System (ADS)

    Dagdug, Leonardo

    2005-04-01

    One of the most important applications of the stochastic matrix method is the evaluation of the probability of forming a ring for B2O3, as a description of the growth process of a solid. In a recent work Dagdug and García-Colín (L. Dagdug and L. S. García-Colín, J. Phys.:Condens. Matter 11, 2193 (1999)) generalized this method for the same substance introducing a probabilistic cut temperature finding a theoretical VFT-like equation for the average relaxation time (or viscosity) of the strong glass forming liquid. To carry out their purpose they take the average relaxation time as inversely proportional to the probability of forming a ring, calculated for a large number of steps of growth. They also use the temperature derivative method to recognize the functional dependence of the relaxation time. Dagdug et. al. (L. Dagdug, L. S. García-Colín and P. Goldstein, Rev. Mex Phys, 2004 (in press)) used the configurational entropy to calculate the isoentropic tempearture for this boron oxide glass using the probability of find boroxol rings and dendrites. With the prediction of the VFT-like equation and the calculation of the isoentropic temperature, in this work, we give a completely theoretical framework to understand the viscosity processes in strong glasses.

  11. Traversing New Theoretical Frames for Intercultural Education: Gender, Intersectionality, Performativity

    ERIC Educational Resources Information Center

    Gregoriou, Zelia

    2013-01-01

    This paper attempts to renegotiate the conceptual and political borders of intercultural education by importing ways of thinking, concepts, aporias and questions relevant to a gendered study of intercultural interactions from theoretical terrains outside the disciplinary borders and discursive limits of intercultural education. A number of…

  12. Theoretical study of production of unique glasses in space

    NASA Technical Reports Server (NTRS)

    Larsen, D. C.

    1974-01-01

    Analytical functional relationships describing homogeneous nucleation and crystallization in various supercooled liquids were developed. The time and temperature dependent relationships of nucleation and crystallization (intrinsic properties) are being used to relate glass forming tendency to extrinsic parameters such as cooling rate through computer simulation. Single oxide systems are being studied initially to aid in developing workable kinetic models and to indicate the primary materials parameters affecting glass formation. The theory and analytical expressions developed for simple systems is then extended to complex oxide systems. A thorough understanding of nucleation and crystallization kinetics of glass forming systems provides a priori knowledge of the ability of a given system to form a glass.

  13. Reducing thermal mismatch stress in anodically bonded silicon-glass wafers: theoretical estimation

    NASA Astrophysics Data System (ADS)

    Sinev, Leonid S.; Ryabov, Vladimir T.

    2017-01-01

    This paper reports the theoretical study and estimations of thermal mismatch stress reduction in anodically bonded silicon-glass stacks by justifiable selection of bonding temperature and glass thickness. This can be done only after prior thorough study of temperature dependence of the linear thermal expansion coefficient of the glass and silicon to be used. We show by analyzing such a dependence of several glass brands that the usual idea of decreasing the bonding process temperature as a solution to the thermal mismatch stress problem can be a failure. Interchanging glass brands during device design is shown to produce very contrasting changes in residual stresses. These results are in good agreement with finite-element modeling. This paper reports there is proportion between glass and silicon wafer thicknesses minimizing thermal mismatch stress at unbonded side of the silicon independently of the bonding or working temperatures chosen.

  14. Genders and sexualities in individuation: theoretical and clinical explorations.

    PubMed

    McKenzie, Susan

    2010-02-01

    Gender assignment, as a key aspect of identity and cultural position, has existed throughout recorded time and across all cultures. An individual's biological sex and particular cultural milieu has a profound effect on their sense of themselves as a gendered being. Sexuality is a more recent marker in identity formation. In the last few decades there has emerged a great deal of interest in the psychology of gender formation, in the interplay of biological sex, culture, brain development, and attachment experiences in the formation of gender identities. Queer theory in its post-modern deconstructionist thinking has suggested that gender is a socially 'constructed' concept having no biological or psychological precursors or realities. Contemporary developmental psychoanalysis is bridging the gap between concepts of gender as purely biological and gender as non-existent. In this paper I explore the emergence of same-sex desire at mid-life, presenting two case histories with extensive dream material. The impact of sexual desire on gender identities is examined through the lenses of culture, dynamic systems theory, neuroscience, and depth psychology. The use of dream analysis as a window into the body/mind movement of gender emergence reflects my sense of gender as a fluidly shifting reality of mind, neither hardwired nor fictional.

  15. Central gender theoretical concepts in health research: the state of the art.

    PubMed

    Hammarström, Anne; Johansson, Klara; Annandale, Ellen; Ahlgren, Christina; Aléx, Lena; Christianson, Monica; Elwér, Sofia; Eriksson, Carola; Fjellman-Wiklund, Anncristine; Gilenstam, Kajsa; Gustafsson, Per E; Harryson, Lisa; Lehti, Arja; Stenberg, Gunilla; Verdonk, Petra

    2014-02-01

    Despite increasing awareness of the importance of gender perspectives in health science, there is conceptual confusion regarding the meaning and the use of central gender theoretical concepts. We argue that it is essential to clarify how central concepts are used within gender theory and how to apply them to health research. We identify six gender theoretical concepts as central and interlinked-but problematic and ambiguous in health science: sex, gender, intersectionality, embodiment, gender equity and gender equality. Our recommendations are that: the concepts sex and gender can benefit from a gender relational theoretical approach (i.e., a focus on social processes and structures) but with additional attention to the interrelations between sex and gender; intersectionality should go beyond additive analyses to study complex intersections between the major factors which potentially influence health and ensure that gendered power relations and social context are included; we need to be aware of the various meanings given to embodiment, which achieve an integration of gender and health and attend to different levels of analyses to varying degrees; and appreciate that gender equality concerns absence of discrimination between women and men while gender equity focuses on women's and men's health needs, whether similar or different. We conclude that there is a constant need to justify and clarify our use of these concepts in order to advance gender theoretical development. Our analysis is an invitation for dialogue but also a call to make more effective use of the knowledge base which has already developed among gender theorists in health sciences in the manner proposed in this paper.

  16. Bending Gender, Ending Gender: Theoretical Foundations for Social Work Practice with the Transgender Community

    ERIC Educational Resources Information Center

    Burdge, Barb J.

    2007-01-01

    Gender is a ubiquitous social construct that wields power over every individual in our society. The traditional dichotomous gender paradigm is oppressive, especially for transgendered people whose sense of themselves as gendered people is incongruent with the gender they were assigned at birth. Transgendered individuals are targeted for…

  17. A theoretical and computational investigation of complex fluids and glasses

    NASA Astrophysics Data System (ADS)

    Lombardo, Thomas G.

    The present dissertation employs molecular simulation and statistical mechanical theories to investigate complex fluids and glasses. The goal is to gain a molecular-level understanding of some of the phenomena present in supercooled liquids, confined water, proteins, glasses, and chiral compounds. The first study examines translational and rotational diffusion in a model of the fragile glass former ortho-terphenyl. The primary objectives are to identify evidence of spatially heterogeneous dynamics and compare how the rates of translation and rotation change relative to one another as the liquid is deeply supercooled. In addition, the breakdown of the Debye model of rotation is analyzed and an alternative formulation of rotational motion is presented. The next study investigates the structure and mechanical properties of glassy water confined between silica-based surfaces with continuously tunable hydrophobicity and hydrophilicity, by computing and analyzing minimum energy and quenched configurations. The maximum sustainable transverse and normal stresses of thin water films are calculated and compared for various confining surfaces. In addition, the mode of mechanical failure is characterized as adhesive or cohesive depending on the strength of interactions between water and the confining surfaces. The third study calculates atomic-level stresses on protein atoms after vitrification. Particular attention is paid to how these stresses change between an equilibrium state at ambient conditions and the quenched or glassy state. The possible effects on protein secondary structure are also analyzed to gauge the ability of theses stresses to disrupt the interactions that stabilize the secondary structure of proteins. The final portion of the dissertation formulates a two-dimensional lattice model to study the equilibrium phase behavior of a ternary mixture composed of two enantiomeric forms of a chiral molecule and a non-chiral liquid solvent. The phase behavior of the

  18. Theoretical issues of gender in the transition from socialist regimes.

    PubMed

    Grapard, U

    1997-09-01

    This article applies a gender perspective to a consideration of the recent economic and political reforms in Eastern and Central Europe. After an introduction and a brief overview of recent empirical studies of the impact of women's economic, political, and social status, the paper explores the difficulties inherent in attempts to create an East-West dialogue on women's interests. The article proposes that these difficulties can be articulated by 1) identifying whether a political regime uses an essentialist (men and women have fundamentally different biological natures) or a social constructionist (most observed differences between men and women are socially created) view to define the nature of women; 2) identifying how these distinct views of gender relations are articulated in the philosophical underpinnings of the two political regimes (the liberal Western system that strictly separates the public and private spheres while assigning different activities for men and women and the socialistic/communistic system that subordinates social reproduction to the sphere of production); and 3) comparing how these views have been articulated in social and institutional arrangements of gender relations in the two regimes. The article then claims that an understanding of the interaction between gender relations, political theory, and social practices in both the West and the East is essential for understanding the problems involved in discussions of the political-economic transition and how it affects men and women.

  19. Theoretical and experimental considerations on the enthalpic relaxation of organic glasses using differential scanning calorimetry.

    PubMed

    Mao, Chen; Chamarthy, Sai Prasanth; Byrn, Stephen R; Pinal, Rodolfo

    2010-01-14

    The enthalpy relaxation of amorphous salicin, used as model organic glass of pharmaceutical relevance, was investigated using a combination of DSC measurements and theoretical simulations. The combined approach makes it possible to discern between the effect of the glass forming properties of the material and the effects of the thermal history and experimental conditions. The approach also facilitates an unambiguous definition of the time scale of the experiment, such that objective comparison among relaxation time and glass transition temperature values can be made. The simulation provides accurate predictions of the DSC profiles obtained under a wide variety of experimental conditions. The effects of annealing time and the heating/cooling rate on the enthalpy recovery were explained by tracking the evolution of relaxation times as a function of temperature and time. The combined experimental and simulation approach also makes it possible to systematically explore the effect of specific glass forming properties, such as fragility and nonexponentiality, on the relaxation and associated thermal behavior of molecular organic glasses of pharmaceutical interest. To fully characterize these materials, it is necessary to go beyond the onset T(g) and include the early stages of the glass transition.

  20. Experimental and theoretical investigation of the elastic moduli of silicate glasses and crystals

    NASA Astrophysics Data System (ADS)

    Philipps, Katharina; Stoffel, Ralf Peter; Dronskowski, Richard; Conradt, Reinhard

    2017-02-01

    A combined quantum-mechanical and thermodynamic approach to the mechanical properties of multicomponent silicate glasses is presented. Quantum chemical calculations based on density-functional theory (DFT) on various silicate systems were performed to explore the crystalline polymorphs existing for a given chemical composition. These calculations reproduced the properties of known polymorphs even in systems with extensive polymorphism, like MgSiO3. Properties resting on the atomic and electronic structure, i.e., molar volumes (densities) and bulk moduli were predicted correctly. The theoretical data (molar equilibrium volumes, bulk moduli) were then used to complement the available experimental data. In a phenomenological evaluation, experimental data of bulk moduli, a macroscopic property resting on phononic structure, were found to linearly scale with the ratios of atomic space demand to actual molar volume in a universal way. Silicates ranging from high-pressure polymorphs to glasses were represented by a single master line. This suggests that above the Debye limit (in practice: above room temperature), the elastic waves probe the short range order coordination polyhedra and their next-neighbor linkage only, while the presence or absence of an extended translational symmetry is irrelevant. As a result, glasses can be treated - with respect to the properties investigated - as commensurable members of polymorphic series. Binary glasses fit the very same line as their one-component end-members, again both in the crystalline and glassy state. Finally, it is shown that the macroscopic properties of multicomponent glasses also are linear superpositions of the properties of their constitutional phases (as determined from phase diagrams or by thermochemical calculations) taken in their respective glassy states. This is verified experimentally for heat capacities and Young’s moduli of industrial glass compositions. It can be concluded, that the combined quantum

  1. Theoretical study of miscibility and glass-forming trends in mixtures of polystyrene spheres

    NASA Technical Reports Server (NTRS)

    Shih, W.-H.; Stroud, D.

    1984-01-01

    A theoretical study of glass-forming trends and miscibility in mixtures of polystyrene spheres (polyballs) of different diameters, suspended in an aqueous solution, is presented. The polyballs are assumed to be charged and to interact via a Debye-Hueckel screened Coulomb potential. The Helmholtz free energy is calculated from a variational principle based on the Gibbs-Bogoliubov inequality, in which a mixture of hard spheres of different diameters is chosen as the reference system. It is found that when the charges of the two types of polyballs are sufficiently different, the variationally determined ratio of hard-sphere diameters differs substantially, leading to packing difficulties characteristic of glass formation. The experimentally observed range of glass formation corresponds to a ratio of hard-sphere diameters of 0.8 or less. Calculations of the free energy as a function of concentration indicate that the liquid polyball mixture is stable against the phase separation, even for widely different polyball charges.

  2. Theoretical study of miscibility and glass-forming trends in mixtures of polystyrene spheres

    NASA Technical Reports Server (NTRS)

    Shih, W.-H.; Stroud, D.

    1984-01-01

    A theoretical study of glass-forming trends and miscibility in mixtures of polystyrene spheres (polyballs) of different diameters, suspended in an aqueous solution, is presented. The polyballs are assumed to be charged and to interact via a Debye-Hueckel screened Coulomb potential. The Helmholtz free energy is calculated from a variational principle based on the Gibbs-Bogoliubov inequality, in which a mixture of hard spheres of different diameters is chosen as the reference system. It is found that when the charges of the two types of polyballs are sufficiently different, the variationally determined ratio of hard-sphere diameters differs substantially, leading to packing difficulties characteristic of glass formation. The experimentally observed range of glass formation corresponds to a ratio of hard-sphere diameters of 0.8 or less. Calculations of the free energy as a function of concentration indicate that the liquid polyball mixture is stable against the phase separation, even for widely different polyball charges.

  3. A theoretical study of the cluster glass-Kondo-magnetic disordered alloys

    NASA Astrophysics Data System (ADS)

    Zimmer, F. M.; Magalhães, S. G.; Coqblin, B.

    2009-10-01

    The physics of disordered alloys, such as typically the well known case of CeNi1-xCux alloys, showing an interplay among the Kondo effect, the spin glass state and a magnetic order, has been studied firstly within an average description like in the Sherrington-Kirkpatrick model. Recently, a theoretical model [S.G. Magalhaes, F.M. Zimmer, P.R. Krebs, B. Coqblin, Phys. Rev. B 74 (2006) 014427] involving a more local description of the intersite interaction has been proposed to describe the phase diagram of CeNi1-xCux. This alloy is an example of the complex interplay between Kondo effect and frustration in which there is in particular the onset of a cluster-glass state. Although the model given in Magalhaes et al. [Phys. Rev. B 74 (2006) 014427] has reproduced the different phases relatively well, it is not able to describe the cluster-glass state. We study here the competition between the Kondo effect and a cluster glass phase within a Kondo-lattice model with an inter-cluster random Gaussian interaction. The inter-cluster term is treated within the cluster mean-field theory for spin glasses [C.M. Sokoulis, Phys. Rev. B 18 (1978) 3757], while, inside the cluster, an exact diagonalisation is performed including inter-site ferromagnetic and intra-site Kondo interactions. The cluster glass order parameters and the Kondo correlation function are obtained for different values of the cluster size, the intra-cluster ferromagnetic coupling and the Kondo intra-site coupling. We obtain that the increase of the Kondo coupling tends clearly to destroy the cluster glass phase.

  4. Gender and Autonomy-Supportive Contexts: Theoretical Perspectives of Self-Determination and Goal Setting

    ERIC Educational Resources Information Center

    Lin, Shinyi; Chen, Yu-Chuan

    2013-01-01

    In integrating theoretical perspectives of self-determination and goal-setting, this study proposes a conceptual model with moderating and mediating effects exploring gender issue in autonomy-supportive learning in higher education as research context. In the proposed model, goal-setting attributes, i.e., individual determinants, social…

  5. On the theoretical determination of the Prigogine-Defay ratio in glass transition.

    PubMed

    Tropin, Timur V; Schmelzer, Jürn W P; Gutzow, Ivan; Schick, Christoph

    2012-03-28

    In a recent analysis [J. W. P. Schmelzer and I. Gutzow, J. Chem. Phys. 125, 184511 (2006)] it was shown for the first time that--in contrast to earlier belief arising from the works of Prigogine and Defay [Chemical Thermodynamics (Longman, London, 1954), Chap. 19; The first French edition of this book was published in 1950] and Davies and Jones [Adv. Phys. 2, 370 (1953); and Proc. R. Soc. London, Ser. A 217, 26 (1953)]--a satisfactory theoretical interpretation of the experimentally observed values of the so-called Prigogine-Defay ratio Π, being a combination of jumps of thermodynamic coefficients at glass transition, can be given employing only one structural order parameter. According to this analysis, this ratio has to be, in full agreement with experimental findings, larger than one (Π > 1). Its particular value depends both on the thermodynamic properties of the system under consideration and on cooling and heating rates. Based on above-mentioned analysis, latter dependence on cooling rates has been studied in detail in another own preceding paper [T. V. Tropin, J. W. P. Schmelzer, and C. Schick, J. Non-Cryst. Solids 357, 1303 (2011)]. In the present analysis, an alternative general method of determination of the Prigogine-Defay ratio is outlined, allowing one to determine this ratio having at ones disposal the generalized equation of state of the glass-forming melts under consideration and, in particular, the knowledge of the equilibrium properties of the melts in the glass transformation range. Employing, as an illustration of the method, a particular model for the description of glass-forming melts, theoretical estimates are given for this ratio being, again, in good agreement with experimental data.

  6. On the theoretical determination of the Prigogine-Defay ratio in glass transition

    NASA Astrophysics Data System (ADS)

    Tropin, Timur V.; Schmelzer, Jürn W. P.; Gutzow, Ivan; Schick, Christoph

    2012-03-01

    In a recent analysis [J. W. P. Schmelzer and I. Gutzow, J. Chem. Phys. 125, 184511 (2006), 10.1063/1.2374894] it was shown for the first time that - in contrast to earlier belief arising from the works of Prigogine and Defay [Chemical Thermodynamics (Longman, London, 1954), Chap. 19; The first French edition of this book was published in 1950] and Davies and Jones [Adv. Phys. 2, 370 (1953), 10.1080/00018735300101252; Davies and Jones Proc. R. Soc. London, Ser. A 217, 26 (1953), 10.1098/rspa.1953.0044] - a satisfactory theoretical interpretation of the experimentally observed values of the so-called Prigogine-Defay ratio Π, being a combination of jumps of thermodynamic coefficients at glass transition, can be given employing only one structural order parameter. According to this analysis, this ratio has to be, in full agreement with experimental findings, larger than one (Π > 1). Its particular value depends both on the thermodynamic properties of the system under consideration and on cooling and heating rates. Based on above-mentioned analysis, latter dependence on cooling rates has been studied in detail in another own preceding paper [T. V. Tropin, J. W. P. Schmelzer, and C. Schick, J. Non-Cryst. Solids 357, 1303 (2011), 10.1016/j.jnoncrysol.2010.12.005]. In the present analysis, an alternative general method of determination of the Prigogine-Defay ratio is outlined, allowing one to determine this ratio having at ones disposal the generalized equation of state of the glass-forming melts under consideration and, in particular, the knowledge of the equilibrium properties of the melts in the glass transformation range. Employing, as an illustration of the method, a particular model for the description of glass-forming melts, theoretical estimates are given for this ratio being, again, in good agreement with experimental data.

  7. Experimental and theoretical study on the driving force and glass flow by laser-induced metal sphere migration in glass

    PubMed Central

    Hidai, Hirofumi; Wada, Jun; Iwamoto, Tatsuki; Matsusaka, Souta; Chiba, Akira; Kishi, Tetsuo; Morita, Noboru

    2016-01-01

    Light is able to remotely move matter. Among various driving forces, laser-induced metal sphere migration in glass has been reported. The temperature on the laser-illuminated side of the sphere was higher than that on the non-illuminated side. This temperature gradient caused non-uniformity in the interfacial tension between the glass and the melted metal as the tension decreased with increasing temperature. In the present study, we investigated laser-induced metal sphere migration in different glasses using thermal flow calculations, considering the temperature dependence of the material parameters. In addition, the velocity of the glass flow generated by the metal sphere migration was measured and compared with thermal flow calculations. The migration velocity of the stainless steel sphere increased with increasing laser power density; the maximum velocity was 104 μm/s in borosilicate glass and 47 μm/s in silica glass. The sphere was heated to more than 2000 K. The temperature gradient of the interfacial tension between the stainless steel sphere and the glass was calculated to be −2.29 × 10−5 N/m/K for borosilicate glass and −2.06 × 10−5 N/m/K for silica glass. Glass flowed in the region 15–30 μm from the surface of the sphere, and the 80-μm sphere migrated in a narrow softened channel. PMID:27934897

  8. A theoretical look at the gender balance of power in the American couple.

    PubMed

    Blumberg, R L; Coleman, M T

    1989-06-01

    Despite the very rich theoretical literature on marital power, recent empirical investigations on this subject have, in general, relied on disappointing measures of power. The empirically testable model developed in this article is an application of Blumberg's general theory of gender stratification to the contemporary American heterosexual couple. In the model, the authors concur with prior studies that identify economic power as the key variable in the power balance within a marital relationship. Their conceptualization of economic power, however, attempts to reflect the extremely complex nature of marital power. Thus, they offer the notion of overall economic power and then suggest that there are a number of discount factors operating at both the macro and micro levels that affect the power balance, resulting in what is termed net economic power. The fully elaborated model is dynamic, taking into account birth cohort differences, stable versus transitional relationships, and cross-class differences.

  9. The Theoretical Intersection of the Looking-Glass-Self and Social Penetration.

    ERIC Educational Resources Information Center

    Hensley, Wayne E.

    This paper focuses on the relationships which exist between the looking-glass-self theory of human behavior of Charles Horton Cooley (published in 1902) and the idea of social penetration of I. Altman and D. Taylor (published in 1973). The paper discusses Cooley's classic metaphor of the looking-glass-self: humans use the verbal and nonverbal…

  10. In search of the glass ceiling: gender and recruitment to management in Norway's state bureaucracy.

    PubMed

    Storvik, Aagoth Elise; Schøne, Pål

    2008-12-01

    There are still fewer female than male managers in Norway's state bureaucracy. This article asks if there are organizational barriers which prevent women from entering these positions. Is there really a glass ceiling, or must one look outside the organizational environment to find an explanation? Is it rather the case that the scarcity of female managers is caused by women's own preferences or their life situations outside work? Or do both contribute to the situation? The study shows that female managers are treated just as well as male managers in central parts of the state bureaucracy. Employers give equal shares of respect and attention to both genders. Female managers are encouraged to apply for the same number of jobs as men and are offered an equal number of jobs as men when they apply; in fact, women are offered more jobs than men, when one controls for the number of job applications. This indicates that organizational barriers are not the problem. The study also shows that there are no differences in work orientation between male and female managers. Female managers are just as ambitious as male managers. Nor do female managers find it more difficult than male managers to combine work and family life. So, how can one explain the low number of female managers? The study shows that one reason can be that female managers apply for management jobs less often than their male colleagues. The cause of this seems to be anticipated discrimination rather than lack of ambition or self-confidence. However, this slows down women's movement into higher management positions in the state bureaucracy.

  11. A National Study of Gender-Based Occupational Segregation in Municipal Bureaucracies: Persistence of Glass Walls?

    ERIC Educational Resources Information Center

    Miller, Will; Kerr, Brinck; Reid, Margaret

    1999-01-01

    Investigates gender-based municipal employment patterns in discrete functional-policy areas. Indicates that even though cities have achieved gender balance in redistributive functions, women are severely underrepresented in distributive and regulatory agencies. (Author)

  12. Theoretical study of population inversion in active doped MIR chalcogenide glass fibre lasers (invited).

    PubMed

    Sujecki, S; Oladeji, A; Phillips, A; Seddon, A B; Benson, T M; Sakr, H; Tang, Z; Barney, E; Furniss, D; Sójka, Ł; Bereś-Pawlik, E; Scholle, K; Lamrini, S; Furberg, P

    We study the mechanism of the population inversion in mid-infrared fibre lasers based on a chalcogenide glass host doped with active lanthanide ions. Three lanthanide dopant ions are considered: terbium, dysprosium and praseodymium. We predict the relevant trivalent ion level populations and gain. The simulation parameters were obtained by fabricating and optically characterising a series of trivalent ion doped chalcogenide glass samples. We also provide simple analytical expressions that aid the design of the cascade lasing process.

  13. Gender.

    ERIC Educational Resources Information Center

    Grauer, Kit

    1996-01-01

    This publication focuses on the theme "Gender." Articles include: (1) "Sex! Violence! Death! Art Education for Boys" (Riita Vira; Finland); (2) "Pedagogy for a Gender Sensitive Art Practice" (Rita Irwin; Canada); (3) "Women's Conscientiousness of Gender in Art and Art Education in Brazil" (Ana Mae Barbosa; Brazil); (4) "Gender Issues in United…

  14. Recognizing the centrality of gender identity and stereotype knowledge in gender development and moving toward theoretical integration: reply to Bandura and Bussey (2004).

    PubMed

    Martin, Carol Lynn; Ruble, Diane N; Szkrybalo, Joel

    2004-09-01

    Most of the critique in the A. Bandura and K. Bussey (see record 2004-18097-001) commentary is a misunderstanding or misrepresentation of the points made by C. L. Martin, D. N. Ruble, and J. Szkrybalo in their 2002 Psychological Bulletin article (see record 2002-18663-003). First, Martin et al. never intended to present a comprehensive theory; instead, it was a review of 2 different cognitive approaches to gender development. Second, there is no time line test that has been failed; instead, gender cognitions may occur earlier than initially believed. Third, Bandura and Bussey dismissed central gender cognitions-gender identity and gender stereotype knowledge-despite considerable evidence in their support. Fourth, Bandura and Bussey never addressed the gaps and ambiguities inherent in their theory that Martin et al. questioned in their earlier article. Finally, Bandura and Bussey's misunderstandings of cognitive theorists' views on socialization agents, sociocultural influences, agency, and motivation created theoretical rifts where none exist. ((c) 2004 APA, all rights reserved)

  15. Theoretical exploration on the magnetic properties of ferromagnetic metallic glass: An Ising model on random recursive lattice

    NASA Astrophysics Data System (ADS)

    Huang, Ran; Zhang, Ling; Chen, Chong; Wu, Chengjie; Yan, Linyin

    2015-07-01

    The ferromagnetic Ising spins are modeled on a recursive lattice constructed from random-angled rhombus units with stochastic configurations, to study the magnetic properties of the bulk Fe-based metallic glass. The integration of spins on the structural glass model well represents the magnetic moments in the glassy metal. The model is exactly solved by the recursive calculation technique. The magnetization of the amorphous Ising spins, i.e. the glassy metallic magnet is investigated by our modeling and calculation on a theoretical base. The results show that the glassy metallic magnets have a lower Curie temperature, weaker magnetization, and higher entropy compared to the regular ferromagnet in crystal form. These findings can be understood with the randomness of the amorphous system, and agree well with other experimental observations.

  16. Theoretical study of production of unique glasses in space. [kinetic relationships describing nucleation and crystallization phenomena

    NASA Technical Reports Server (NTRS)

    Larsen, D. C.; Sievert, J. L.

    1975-01-01

    The potential of producing the glassy form of selected materials in the weightless, containerless nature of space processing is examined through the development of kinetic relationships describing nucleation and crystallization phenomena. Transformation kinetics are applied to a well-characterized system (SiO2), an excellent glass former (B2O3), and a poor glass former (Al2O3) by conventional earth processing methods. Viscosity and entropy of fusion are shown to be the primary materials parameters controlling the glass forming tendency. For multicomponent systems diffusion-controlled kinetics and heterogeneous nucleation effects are considered. An analytical empirical approach is used to analyze the mullite system. Results are consistent with experimentally observed data and indicate the promise of mullite as a future space processing candidate.

  17. A theoretical interpretation of the chemical shift of 29Si NMR peaks in alkali borosilicate glasses

    NASA Astrophysics Data System (ADS)

    Nanba, Tokuro; Nishimura, Mitsunori; Miura, Yoshinari

    2004-12-01

    In 29Si-NMR, it has so far been accepted that the chemical shifts of Q n species (SiO 4 units containing n bridging oxygens) were equivalent between alkali borosilicate and boron-free alkali silicate glasses. In the sodium borosilicate glasses with low sodium content, however, a contradiction was confirmed in the estimation of alkali distribution; 11B NMR suggested that Na ions were entirely distributed to borate groups to form BO 4 units, whereas a -90 ppm component was also observed in 29Si-NMR spectra, which has been attributed to Q 3 species associated with a nonbridging oxygen (NBO). Then, cluster molecular orbital calculations were performed to interpret the -90 ppm component in the borosilicate glasses. It was found that a silicon atom which had two tetrahedral borons (B4) as its second nearest neighbors was similar in atomic charge and Si2p energy to the Q 3 species in boron-free alkali silicates. Unequal distribution of electrons in Si-O-B4 bridging bonds was also found, where much electrons were localized on the Si-O bonds. It was finally concluded that the Si-O-B4 bridges with narrow bond angle were responsible for the -90 ppm 29Si component in the borosilicate glasses. There still remained another interpretation; the Q 3 species were actually present in the glasses, and NBOs in the Q 3 species were derived from the tricluster groups, such as (O 3Si)O(BO 3) 2. In the glasses with low sodium content, however, it was concluded that the tricluster groups were not so abundant to contribute to the -90 ppm component.

  18. Experimental and theoretical studies of the structure of tellurate-borate glasses network.

    PubMed

    Rada, Simona; Culea, Eugen; Neumann, Manfred

    2010-08-01

    The structural properties of the xTeO(2) x (1-x)B(2)O(3) glasses (x = 0.6; 0.7) were investigated by FT-IR spectroscopy. From the analysis of the FTIR spectra, it is reasonable to assume that by the increasing of boron ions content, the tetrahedral [BO(4)] units are gradually replaced by the trigonal [BO(3)] units. The increase in the number of non-bridging oxygen atoms would decrease the connectivity of the glass network and will yield the depolymerization of the borate chains. The molecular structure and vibrational frequencies of the proposed structural models have been studied by exploring the density functional theory (DFT) calculations. The FTIR spectra of the xTeO(2) x (1-x)B(2)O(3) vitreous systems were compared with the calculated spectrum. This procedure allowed us to assign most of the observed IR bands.

  19. Enthalpy Recovery of Polymeric Glasses: Is the Theoretical Limiting Liquid Line Reached?

    NASA Astrophysics Data System (ADS)

    Li, Qingxiu; Simon, Sindee

    2006-03-01

    Glasses are inherently non-equilibrium materials, and consequently, their properties evolve toward equilibrium in a process known as structural recovery or physical aging. Recently, several authors have suggested that the equilibrium liquid line is not reached even when properties have ceased to evolve. In this work, we present measurements of the enthalpy recovery of polystyrene (PS) at temperatures ranging from the vicinity of glass transition temperature to 10 C below Tg (90 C), for aging times up to 200 days. The results are analyzed in the context of the TNM model of structural recovery. In addition, we analyze data in the literature to determine whether enthalpy recovery ceases prior to the material reaching the equilibrium liquid line obtained by extrapolation of the liquid line above Tg. The results suggest that, in fact, the liquid enthalpy line is reached at temperatures below Tg when equilibrium is reached, i.e., when properties cease to evolve.

  20. Theoretical study of the devitrification of the metallic glass Ni80B20

    NASA Astrophysics Data System (ADS)

    Somoza, J. A.; Gallego, L. J.

    2000-02-01

    The devitrification of Ni80B20 metallic glass has recently been investigated experimentally by two different groups with contradictory results. Rojo et al. interpret their data as showing that devitrification occurs in two successive processes separated by a state in which pure amorphous Ni is present. By contrast, Riveiro et al. have suggested that the ``intermediate'' state consists of two crystalline phases. Using a semiempirical treatment which combines classical elasticity theory and Miedema's model for the heat of formation of alloys, we have constructed the free energy diagram for Ni-B. We found that it supports Riveiro et al.'s account of the devitrification of Ni80B20 glass rather than Rojo et al.'s.

  1. Gender Structure and Women's Agency: Toward Greater Theoretical Understanding of Education for Transformation

    ERIC Educational Resources Information Center

    Stromquist, Nelly P.

    2015-01-01

    Under the research radar, and yet highly influential in transformation of practices concerning the social understanding and enactment of gender, are women-led non-governmental organizations (WNGOs). Their continued efforts to reconfigure gender identities and their impact on public policy formation have expanded notions of citizenship and…

  2. Gender Structure and Women's Agency: Toward Greater Theoretical Understanding of Education for Transformation

    ERIC Educational Resources Information Center

    Stromquist, Nelly P.

    2015-01-01

    Under the research radar, and yet highly influential in transformation of practices concerning the social understanding and enactment of gender, are women-led non-governmental organizations (WNGOs). Their continued efforts to reconfigure gender identities and their impact on public policy formation have expanded notions of citizenship and…

  3. Theoretical Perspectives on Gender in Education: The Case of Eastern and Southern Africa

    NASA Astrophysics Data System (ADS)

    Mannathoko, Changu

    1999-11-01

    In recent years, throughout Eastern and Southern Africa, there has been a proliferation of research on gender in education. It is possible to point to a wide variety of publications, courses and programmes planned and organized by universities, national governments, international organizations, non-governmental organizations and the private sector relating to this field. This article examines the feminist and gender theories underpinning all these endeavors. The theories are assessed for their potential capacity to assist in elucidating the complex relationship between gender and development within the region.

  4. Gender-gaps and glass ceilings: A survey of gender-specific publication trends in Psychiatry between 1994 and 2014.

    PubMed

    Süßenbacher, S; Amering, M; Gmeiner, A; Schrank, B

    2017-07-01

    Within academic psychiatry, women are underrepresented in the higher academic ranks. However, basic determinants of women's lack of academic advancement such as publication activity are poorly understood. The present study examines women's publication activity in high-impact psychiatry journals over two decades and reports developments in the numbers of male and female authorship over time and across cultural areas. We conducted a retrospective bibliometric review of all articles published in 2004 and 2014 in three high-ranking general psychiatry journals. Statistical comparisons were made between the two years and with results from a baseline assessment in 1994. The overall percentage of female authors increased from 24.6% in 1994 to 33.2% in 2004 to 38.9% in 2014. Though increases in female authorship were statistically significant for both decades, there was less difference between 2004 and 2014, indicating a possible ceiling effect. Rates of female first authors increased between 1994 and 2014, though to a lesser degree between 2004 and 2014. Numbers of female corresponding authors plateaued between 2004 and 2014. Within Europe, Scandinavia displayed the most balanced gender-wise first author ratios. Western European and Central European countries increased their rates of female first authors substantially between 2004 and 2014. Despite gains in some areas, our study reveals considerable deficits in the diversity of the current academic psychiatric landscape. Ongoing efforts and interventions to enhance the participation of underrepresented groups on institutional, political and editorial levels are necessary to diversify psychiatric research. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  5. Theoretical studies on the electronic structure and properties of complex ceramic crystals and glasses

    SciTech Connect

    Ching, Wai-Yim.

    1991-01-24

    This progress report summarizes the accomplishment of the DOE-support research program at the University of Missouri-Kansas City for the period July 1, 1991--June 30, 1992. This is the second year of a three-year renewal. The major accomplishments for the year are: (a) Initiation of fundamental studies on the electronic properties of C{sub 60} and related crystals; (b) study of electronic structures and optical properties of several important ceramic crystals, especially on AlN, SiO{sub 2} and Al{sub 2}O{sub 3}; (c) first-principles calculation of total energies and structural phase transitions in oxides, nitrides, and borides; (d) theory of magnetism in Nd{sub 2}Fe{sub 14}B permanent magnetic alloy. The major focus for the next year's effort will be on the following areas: (1) Continuation of the fundamental studies on the buckminsterfullerene system with particular emphasis on the alkali-doped superconducting fullerides. (2) Fundamental studies on the structure and properties of Boron and B-related compounds. (3) Basic studies on the structural and electronic properties of metallic glasses with particular emphasis on the magnetic glasses. (4) Further development of the first-principles OLCAO method for applications to super-complex systems.

  6. Up Against the Glass Ceiling: Culture and Gender in the Workplace.

    ERIC Educational Resources Information Center

    Cordeiro, Paula A.

    1997-01-01

    Uses a cultural map exercise to show how culture affects educators' perspectives of gender issues in school administration. Discusses individual cultural identity and the influences of educators' societal/national, regional/linguistic or racial/ethnic, and individual belief cultures. Feminist theory and its premises can help everyone understand…

  7. "The Glass Ceiling Is Kind of a Bummer": Women's Reflections on a Gender Development Course

    ERIC Educational Resources Information Center

    Sharp, Elizabeth A.; SoRelle-Miner, Danielle; Bermudez, Judith M.; Walker, Maria

    2008-01-01

    The purpose of this study was to explore women students' experiences and reactions to a core Human Development and Family Studies (HDFS) class cross-listed with Women's Studies (WS). Using 6 focus groups with 22 women, we found that the course increased "awareness of gender" (Theme A) but was limited partially because of patriarchical beliefs,…

  8. Hour-glass ceilings: Work-hour thresholds, gendered health inequities.

    PubMed

    Dinh, Huong; Strazdins, Lyndall; Welsh, Jennifer

    2017-03-01

    Long workhours erode health, which the setting of maximum weekly hours aims to avert. This 48-h limit, and the evidence base to support it, has evolved from a workforce that was largely male, whose time in the labour force was enabled by women's domestic work and care giving. The gender composition of the workforce has now changed, and many women (as well as some men) combine care-giving with paid work, a change viewed as fundamental for gender equality. However, it raises questions on the suitability of the work time limit and the extent it is protective of health. We estimate workhour-mental health thresholds, testing if they vary for men and women due to gendered workloads and constraints on and off the job. Using six waves of data from a nationally representative sample of Australian adults (24-65 years), surveyed in the Household Income Labour Dynamics of Australia Survey (N = 3828 men; 4062 women), our study uses a longitudinal, simultaneous equation approach to address endogeneity. Averaging over the sample, we find an overall threshold of 39 h per week beyond which mental health declines. Separate curves then estimate thresholds for men and women, by high or low care and domestic time constraints, using stratified and pooled samples. We find gendered workhour-health limits (43.5 for men, 38 for women) which widen further once differences in resources on and off the job are considered. Only when time is 'unencumbered' and similar time constraints and contexts are assumed, do gender gaps narrow and thresholds approximate the 48-h limit. Our study reveals limits to contemporary workhour regulation which may be systematically disadvantaging women's health.

  9. Theoretical Studies of the Spin Hamiltonian Parameters and Local Distortions for Cu2+ in Alkaline Earth Lead Zinc Phosphate Glasses

    NASA Astrophysics Data System (ADS)

    Wang, Bo-Kun; Wu, Shao-Yi; Yuan, Zi-Yi; Liu, Zi-Xuan; Jiang, Shi-Xin; Liu, Zheng; Yao, Zi-Jian; Teng, Bao-Hua; Wu, Ming-He

    2016-08-01

    The spin Hamiltonian parameters and local structures are theoretically studied for Cu2+-doped alkaline earth lead zinc phosphate (RPPZ, R=Mg, Ca, Sr, and Ba) glasses based on the high-order perturbation calculations for a tetragonally elongated octahedral 3d9 cluster. The relative elongation ratios are found to be ρ≈3.2%, 4.4%, 4.6%, and 3.3% for R=Mg, Ca, Sr, and Ba, respectively, because of the Jahn-Teller effect. The whole decreasing crystal-field strength Dq and orbital reduction factor k from Mg to Sr are ascribed to the weakening electrostatic coulombic interactions and the increasing probability of productivity of nonbridge oxygen (and hence increasing Cu2+-O2- electron cloud admixtures) under PbO addition, respectively, with increasing alkali earth ionic radius. The anomalies (the largest Dq and the next highest k among the systems) for R=Ba are attributed to the cross linkage of this large cation in the network. The overall increasing order (Mg≤Baglasses containing copper dopants.

  10. How Welfare States Shape the Gender Pay Gap: A Theoretical and Comparative Analysis

    ERIC Educational Resources Information Center

    Mandel, Hadas; Shalev, Michael

    2009-01-01

    We assess the impact of the welfare state on cross-national variation in the gender wage gap. Earnings inequality between men and women is conceptualized as resulting from their different locations in the class hierarchy, combined with the severity of wage differentials between and within classes. This decomposition contributes to identifying…

  11. Nation-Level Indicators of Gender Equity in Psychological Research: Theoretical and Methodological Issues

    ERIC Educational Resources Information Center

    Hyde, Janet Shibley

    2012-01-01

    Power and inequality are central concepts in feminist theory and practice. Yet, with a few notable exceptions, there is relatively little empirical research on gender and power within feminist psychology. A search of PsycINFO for articles published in "Psychology of Women Quarterly" for the years 2000-2011 yielded only 14 empirical articles with…

  12. Nation-Level Indicators of Gender Equity in Psychological Research: Theoretical and Methodological Issues

    ERIC Educational Resources Information Center

    Hyde, Janet Shibley

    2012-01-01

    Power and inequality are central concepts in feminist theory and practice. Yet, with a few notable exceptions, there is relatively little empirical research on gender and power within feminist psychology. A search of PsycINFO for articles published in "Psychology of Women Quarterly" for the years 2000-2011 yielded only 14 empirical articles with…

  13. How Welfare States Shape the Gender Pay Gap: A Theoretical and Comparative Analysis

    ERIC Educational Resources Information Center

    Mandel, Hadas; Shalev, Michael

    2009-01-01

    We assess the impact of the welfare state on cross-national variation in the gender wage gap. Earnings inequality between men and women is conceptualized as resulting from their different locations in the class hierarchy, combined with the severity of wage differentials between and within classes. This decomposition contributes to identifying…

  14. Delayed solidification of soft glasses: new experiments, and a theoretical challenge.

    PubMed

    Joshi, Yogesh M; Shahin, A; Cates, Michael E

    2012-01-01

    When subjected to large amplitude oscillatory shear stress, aqueous Laponite suspensions show an abrupt solidification transition after a long delay time t(c). We measure the dependence of t(c) on stress amplitude, frequency, and on the age-dependent initial loss modulus. At first sight our observations appear quantitatively consistent with a simple soft-glassy rheology (SGR)-type model, in which barrier crossings by mesoscopic elements are purely strain-induced. For a given strain amplitude gamma0 each element can be classified as fluid or solid according to whether its local yield strain exceeds gamma0. Each cycle, the barrier heights E of yielded elements are reassigned according to a fixed prior distribution rho(E): this fixes the per-cycle probability R(gamma0) of a fluid elements becoming solid. As the fraction of solid elements builds up, gamma0 falls (at constant stress amplitude), so R(gamma0) increases. This positive feedback accounts for the sudden solidification after a long delay. The model thus appears to directly link macroscopic rheology with mesoscopic barrier height statistics: within its precepts, our data point towards a power law for rho(E) rather than the exponential form usually assumed in SGR. However, despite this apparent success, closer investigation shows that the assumptions of the model cannot be reconciled with the extremely large strain amplitudes arising in our experiments. The quantitative explanation of delayed solidification in Laponite therefore remains an open theoretical challenge.

  15. Fractal Dimension of Interfaces in Edwards-Anderson and Long-range Ising Spin Glasses: Determining the Applicability of Different Theoretical Descriptions

    NASA Astrophysics Data System (ADS)

    Wang, Wenlong; Moore, M. A.; Katzgraber, Helmut G.

    2017-09-01

    The fractal dimension of excitations in glassy systems gives information on the critical dimension at which the droplet picture of spin glasses changes to a description based on replica symmetry breaking where the interfaces are space filling. Here, the fractal dimension of domain-wall interfaces is studied using the strong-disorder renormalization group method pioneered by Monthus [Fractals 23, 1550042 (2015), 10.1142/S0218348X15500425] both for the Edwards-Anderson spin-glass model in up to 8 space dimensions, as well as for the one-dimensional long-ranged Ising spin-glass with power-law interactions. Analyzing the fractal dimension of domain walls, we find that replica symmetry is broken in high-enough space dimensions. Because our results for high-dimensional hypercubic lattices are limited by their small size, we have also studied the behavior of the one-dimensional long-range Ising spin-glass with power-law interactions. For the regime where the power of the decay of the spin-spin interactions with their separation distance corresponds to 6 and higher effective space dimensions, we find again the broken replica symmetry result of space filling excitations. This is not the case for smaller effective space dimensions. These results show that the dimensionality of the spin glass determines which theoretical description is appropriate. Our results will also be of relevance to the Gardner transition of structural glasses.

  16. Theoretical study on the composition location of the best glass formers in Cu-Zr amorphous alloys.

    PubMed

    Wang, Da; Zhao, Shi-Jin; Liu, Li-Min

    2015-01-29

    This study combines the molecular dynamics (MD) simulations and first-principles approach to explain the experimental observation that the best glass formers of Cu-Zr bulk metallic glasses (BMGs) have the compositions Cu50Zr50 and Cu64Zr36. These two best glass formers are first calculated to be most abundantly composed of Cu6Zr7 and Cu8Zr5 icosahedral clusters when compared in the compositional range of CuxZr100-x (45 ≤ x ≤ 70), and then these two icosahedral clusters are calculated to have the lowest formation energy among the icosahedral clusters CuxZr13-x (3 ≤ x ≤ 10), as well as possessing some characteristics in electronic structure and chemical hardness. Through understanding the properties of specific icosahedral clusters in metallic glasses, the structural and energetic contribution to the glass-forming ability are systematically discussed.

  17. Becoming Who We Are: A Theoretical Explanation of Gendered Social Structures and Social Networks that Shape Adolescent Interpersonal Aggression

    ERIC Educational Resources Information Center

    Smith, Paige Hall; White, Jacquelyn W.; Moracco, Kathryn E.

    2009-01-01

    A conceptualization of gendered interpersonal aggression that is grounded in the social ecological framework is presented to explicate factors in adolescents' gendered environments that give rise to aggression and victimization. The focus is on gendered social structures and social networks. Our framework for prevention suggests that violence…

  18. Experimental and theoretical study of the laser micro-machining of glass using high-repetition-rate ultrafast laser

    NASA Astrophysics Data System (ADS)

    Yashkir, Yuri; Liu, Qiang

    2006-04-01

    We present a systematic study of the ultrafast laser micro-machining of glass using a Ti:Spp laser with moderate pulse energy (<5 μJ) at a high repetition rate (50 kHz). Optimal conditions were identified for high resolution surface laser etching, and via drilling. Several practical applications were developed: glass templates for micro fluid diffraction devices, phase gratings for excimer laser projection techniques, micro fluid vertical channel-connectors, etc. It is demonstrated that the interaction of ultrafast laser pulses with glass combines several different processes (direct ablation, explosive material ejection, and thermal material modification). A dynamic numerical model was developed for this process. It was successfully used for modelling of laser micro-machining with arbitrary 3D translations of the target.

  19. A theoretical study of the spin glass-Kondo-magnetic disordered alloys in the presence of a random field

    NASA Astrophysics Data System (ADS)

    Magalhaes, S. G.; Zimmer, F. M.; Coqblin, B.

    2012-12-01

    We study here the influence of a random applied magnetic field on the competition between the Kondo effect, the spin glass phase and a ferromagnetic order in disordered cerium systems such as CeNi1-xCux. The model used here takes an intrasite Kondo coupling and an intersite random coupling; both the intersite random coupling and the random magnetic field are described within the Sherrington-Kirkpatrick model and the one-step replica symmetry breaking procedure is also used here. We present phase diagrams giving Temperature versus the Kondo exchange parameter and the random magnetic field makes decrease particularly the importance of the spin glass and ferromagnetic phases.

  20. Theoretical simulation of a polarization splitter based on dual-core soft glass PCF with micron-scale gold wire

    NASA Astrophysics Data System (ADS)

    Liu, Qiang; Li, Shuguang; Wang, Xinyu; Shi, Min

    2016-12-01

    A polarization splitter based on dual-core soft glass photonic crystal fiber (PCF) filled with micron-scale gold wire is proposed. The characteristics of the polarization splitter are studied by changing the structural parameters of the PCF and the diameter of the gold wire with the finite element method (FEM). The simulation results reveal that the coupling length ratio of the soft glass-based PCF is close to 2 and the corresponding curve is more flat than that of the silica-based PCF. The broadband bandwidth is 226 nm in which the extinction ratio is lower than -20 dB by the soft glass-based PCF, i.e., from 1465 nm to 1691 nm which is competitive in the reported polarization splitters, and the bandwidth is just 32 nm by the silica-based PCF. The insertion loss by our polarization splitter is just 0.00248 dB and 0.43 dB at the wavelength of 1.47 μm and 1.55 μm. The birefringence is obviously increased and the coupling length is decreased by filling gold wire into the soft glass-based or the silica-based PCF. Also the birefringence based on the silica-based PCF is much larger than that based on the soft glass-based PCF whether or not the gold wire is introduced. The fabrication tolerance of the polarization splitter is also considered by changing the structural parameters. The polarization splitter possesses broad bandwidth, low insertion loss, simple structure and high fabrication tolerance. Project supported by the National Natural Science Foundation of China (Grant Nos. 61178026, 61475134, and 61505175).

  1. Theoretical and experimental evaluation of double-notch shear strength of G-10CR glass-cloth/epoxy laminates at cryogenic temperatures

    SciTech Connect

    Shindo, Y.; Wang, R.; Horiguchi, K.; Ueda, S.

    1999-07-01

    the cryogenic interlaminar shear behavior of G-10CR glass-cloth/epoxy laminates has been discussed through theoretical and experimental characterizations. The use of the double-notch shear test for measuring the interlaminar shear strength of glass-cloth/epoxy laminates at low temperatures is evaluated first. The interlaminar shear tests were carried out with double-notch shear specimens at room temperature, 77 K and 4 K to evaluate the interlaminar shear strength (ILSS) of G-10CR glass-cloth/epoxy laminates. The double-notch shear specimen was loaded on its ends in compression with a supporting jig to prevent buckling. These tests were conducted in accordance with ASTM D3846-79. The effects of temperature, specimen thickness, and notch separation on the apparent ILSS are shown graphically. Fracture surfaces were examined by scanning electron microscopy (SEM) and optical microscopy to verify the failure mechanisms. A three-dimensional finite element analysis was also performed to investigate the effect of specimen thickness and notch separation on the shear stress distribution in the expected fracture plane. Effective elastic moduli were determined under the assumption of uniform strain inside the representative volume element. The numerical findings are then correlated with the experimental results. The validity of this test technique has been established.

  2. Theoretical Study of Role of Sb in Se_0.85-xTe_0.15Sbx Chalcogenide Glass in Influencing Glass Transition Temperature

    NASA Astrophysics Data System (ADS)

    Maharjan, N. B.; Paudyal, D. D.; Jeong, J.; Scheicher, R. H.; Das, T. P.

    2001-03-01

    The influence of Sb impurity on glass transition temperature (Tg) has recently been studied using Differential Scanning Calorimetry(N. B. Maharjan et al., Phy. Stat. Sol. (a) 178, 663 (2000)). The results indicate that Tg initially increases with Sb concentration (x), reaching a maximum at 0.04, subsequently decreasing till x=0.06 and then becoming constant. Qualitative explanation of this behavior for Tg has been suggested^1 using earlier ideas in the literature regarding the role of Sb in the interaction between chains in the Se_1-xTex system and bond energy strength considerations involving Se-Se and Sb-Se bonds. These ideas are being tested quantitatively using Hartree-Fock Cluster procedures, previously utilized by our group for study(H. S. Cho et al., (to be published); H. S. Cho et al., Hyperfine Interactions 96, 213 (1995)) of nuclear quadrupole interactions including that of ^125Te in Selenium and Tellurium(P. Boolchand et al., Phys. Rev. Lett. 30, 1292 (1973)).

  3. A Theoretical Study of Love Wave Sensors Based on ZnO–Glass Layered Structures for Application to Liquid Environments

    PubMed Central

    Caliendo, Cinzia; Hamidullah, Muhammad

    2016-01-01

    The propagation of surface acoustic Love modes along ZnO/glass-based structures was modeled and analysed with the goal of designing a sensor able to detect changes in the environmental parameters, such as liquid viscosity changes and minute amounts of mass supported in the viscous liquid medium. Love mode propagation was modeled by numerically solving the system of coupled electro-mechanical field equations and Navier–Stokes equations. The phase and group velocities and the attenuation of the acoustic wave propagating along the 30° tilted c-axis ZnO/glass structure contacting a viscous non-conductive liquid were calculated for different ZnO guiding layer thicknesses, added mass thicknesses, and liquid viscosity and density. The three sensor responses, i.e., the wave phase and group velocity, and attenuation changes are calculated for different environmental parameters and related to the sensor velocity and attenuation sensitivities. The resulted sensitivities to liquid viscosity and added mass were optimized by adjusting the ZnO guiding layer thickness corresponding to a sensitivity peak. The present analysis is valuable for the manufacture and application of the ZnO-glass structure Love wave sensors for the detection of liquid properties, such as viscosity, density and mass anchored to the sensor surface. PMID:27918419

  4. A Theoretical Study of Love Wave Sensors Based on ZnO-Glass Layered Structures for Application to Liquid Environments.

    PubMed

    Caliendo, Cinzia; Hamidullah, Muhammad

    2016-12-02

    The propagation of surface acoustic Love modes along ZnO/glass-based structures was modeled and analysed with the goal of designing a sensor able to detect changes in the environmental parameters, such as liquid viscosity changes and minute amounts of mass supported in the viscous liquid medium. Love mode propagation was modeled by numerically solving the system of coupled electro-mechanical field equations and Navier-Stokes equations. The phase and group velocities and the attenuation of the acoustic wave propagating along the 30° tilted c-axis ZnO/glass structure contacting a viscous non-conductive liquid were calculated for different ZnO guiding layer thicknesses, added mass thicknesses, and liquid viscosity and density. The three sensor responses, i.e., the wave phase and group velocity, and attenuation changes are calculated for different environmental parameters and related to the sensor velocity and attenuation sensitivities. The resulted sensitivities to liquid viscosity and added mass were optimized by adjusting the ZnO guiding layer thickness corresponding to a sensitivity peak. The present analysis is valuable for the manufacture and application of the ZnO-glass structure Love wave sensors for the detection of liquid properties, such as viscosity, density and mass anchored to the sensor surface.

  5. [Glass maze in women's leadership].

    PubMed

    Barberá Heredia, Ester; Ramos López, Amparo; Candela Agulló, Carlos

    2011-04-01

    Psychological gender discrimination explanations have changed over the past thirty years, becoming more complex in order to obtain a better understanding of the social reality. At the present moment, one of the most interesting research areas is the one referring to the 'glass maze' phenomenon in women's management careers. The main purpose of this work is to reveal the theoretical evolution in an attempt to explain the leadership study from a gender perspective. The consecutive hypotheses, starting with the labour sexual division idea, are becoming more interactive in order to understand the current labour-social situation. Social psychology has underlined the role of beliefs, observed via gender stereotyped roles, prejudiced attitudes against women, sexist and neo-sexist ideology, or masculine, feminine and androgynous identity development. New psychological interpretations insist on the variability of the gender concept, where gender is sometimes observed through men and women's behaviours, and other times through those behaviour expectations. But gender is mainly observed though the power relations between men and women during social interactions in labour organizations.

  6. Spin-glass behavior of Sn0.9Fe3.1N: An experimental and quantum-theoretical study

    NASA Astrophysics Data System (ADS)

    Scholz, Tanja; Dronskowski, Richard

    2016-05-01

    Based on comprehensive experimental and quantum-theoretical investigations, we identify Sn0.9Fe3.1N as a canonical spin glass and the first ternary iron nitride with a frustrated spin ground state. Sn0.9Fe3.1N is the end member of the solid solution SnxFe4-xN (0 < x ≤ 0.9) derived from ferromagnetic γ'-Fe4N. Within the solid solution, the gradual incorporation of tin is accompanied by a drastic weakening of the ferromagnetic interactions. To explore the dilution of the ferromagnetic coupling, the highly tin-substituted Sn0.9Fe3.1N has been magnetically reinvestigated. DC magnetometry reveals diverging susceptibilities for FC and ZFC measurements at low temperatures and an unsaturated hysteretic loop even at high magnetic fields. The temperature dependence of the real component of the AC susceptibility at different frequencies proves the spin-glass transition with the characteristic parameters Tg = 12.83(6) K, τ* = 10-11.8(2) s, zv = 5.6(1) and ΔTm/(Tm ṡ Δlgω) = 0.015. The time-dependent response of the magnetic spins to the external field has been studied by extracting the distribution function of relaxation times g(τ, T) up to Tg from the complex plane of AC susceptibilities. The weakening of the ferromagnetic coupling by substituting tin into γ'-Fe4N is explained by the Stoner criterion on the basis of electronic structure calculations and a quantum-theoretical bonding analysis.

  7. Spin-glass behavior of Sn{sub 0.9}Fe{sub 3.1}N: An experimental and quantum-theoretical study

    SciTech Connect

    Scholz, Tanja; Dronskowski, Richard

    2016-05-15

    Based on comprehensive experimental and quantum-theoretical investigations, we identify Sn{sub 0.9}Fe{sub 3.1}N as a canonical spin glass and the first ternary iron nitride with a frustrated spin ground state. Sn{sub 0.9}Fe{sub 3.1}N is the end member of the solid solution Sn{sub x}Fe{sub 4−x}N (0 < x ≤ 0.9) derived from ferromagnetic γ′-Fe{sub 4}N. Within the solid solution, the gradual incorporation of tin is accompanied by a drastic weakening of the ferromagnetic interactions. To explore the dilution of the ferromagnetic coupling, the highly tin-substituted Sn{sub 0.9}Fe{sub 3.1}N has been magnetically reinvestigated. DC magnetometry reveals diverging susceptibilities for FC and ZFC measurements at low temperatures and an unsaturated hysteretic loop even at high magnetic fields. The temperature dependence of the real component of the AC susceptibility at different frequencies proves the spin-glass transition with the characteristic parameters T{sub g}  =  12.83(6) K, τ{sup *} = 10{sup −11.8(2)} s, zv = 5.6(1) and ΔT{sub m}/(T{sub m} ⋅ Δlgω) = 0.015. The time-dependent response of the magnetic spins to the external field has been studied by extracting the distribution function of relaxation times g(τ, T) up to T{sub g} from the complex plane of AC susceptibilities. The weakening of the ferromagnetic coupling by substituting tin into γ′-Fe{sub 4}N is explained by the Stoner criterion on the basis of electronic structure calculations and a quantum-theoretical bonding analysis.

  8. An Evaluation of a Theoretical Model Predicting Dieting Behaviors: Tests of Measurement and Structural Invariance across Ethnicity and Gender

    ERIC Educational Resources Information Center

    Boie, Ioana; Lopez, Anna L.; Sass, Daniel A.

    2013-01-01

    This study evaluated a model linking internalization and dieting behaviors in a sample ("n" = 499) of Latina/o and White college students. Analyses revealed that the scales were invariant across ethnic and gender groups and generally supported the invariance of the proposed model across these groups. Analyses also revealed no ethnic mean…

  9. Theoretical prediction of Grüneisen parameter for SiO2.TiO2 bulk metallic glasses

    NASA Astrophysics Data System (ADS)

    Singh, Chandra K.; Pandey, Anjani K.; Pandey, Brijesh K.

    2016-05-01

    The Grüneisen parameter (γ) is very important to decide the limitations for the prediction of thermoelastic properties of bulk metallic glasses. It can be defined in terms of microscopic and macroscopic parameters of the material in which former is based on vibrational frequencies of atoms in the material while later is closely related to its thermodynamic properties. Different formulation and equation of states are used by the pioneer researchers of this field to predict the true sense of Gruneisen parameter for BMG but for SiO2.TiO2 very few and insufficient information is available till now. In the present work we have tested the validity of two different isothermal EOS viz. Poirrior-Tarantola EOS and Usual-Tait EOS to predict the true value of Gruneisen parameter for SiO2.TiO2 as a function of compression. Using different thermodynamic limitations related to the material constraints and analyzing obtained result it is concluded that the Poirrior-Tarantola EOS gives better numeric values of Grüneisen parameter (γ) for SiO2.TiO2 BMG.

  10. Manufacture and experimental and theoretical evaluation of adaptative glass/epoxy composites with embedded shape memory alloy wires

    NASA Astrophysics Data System (ADS)

    Choi, Young-Kuk; Salvia, Michelle

    2001-07-01

    Adaptable hybrid composites are materials into which actuators are embedded in polymer matrix composites. Shape memory alloys (SMA) are amongst the potential candidates for actuators embedded in such composite smart structures. In order to test the influence of the processing conditions on the actuation properties of adaptive hybrid composites, a model system based on a glass epoxy asymmetric laminate composite with prestrained shape memory nitinol-copper wires, was used. When the SMA wires were electrically heated and cooled, undergoing a reversible martensite to austenite transformation, reversible bending of the host composite was observed. The most important deflection of the host composite was obtained for the material, processed with embedded wires in TWSME conditions. Nevertheless, for samples just prestrained for the OWSME, a self-training effect occurred in relation to the reverse polarized austenite to martensite transformation, during cooling after actuation. The experimental results obtained in the conditions of the sample processed with embedded wires in TWSME conditions can be modeled in the frame of recent phenomenological modeling. In spite of some drastic simplifications, the quasi-linear variation of the bending effect with temperature is correctly described using the metallurgical parameters defined from the Clausius-Clapeyron diagrams of this alloy previously determined.

  11. Gender Problems in the Practice of Professional Interpreters Assisting Migrant Women in Australia: A Theoretical Case for Feminist Education.

    PubMed

    Norma, Caroline; Garcia-Caro, Olga

    2016-10-01

    Professional interpreters in Australia have little opportunity to undertake education on issues of violence against women. This article observes a lack of awareness of gender violence-related issues among community interpreters. It then notes examples of gender-related problems arising in the work of interpreters assisting migrant women. It repeats Maree Pardy's call for interpreter education, but diverges from her 1995 work by explicitly recommending this education be informed by feminist principles. It observes that, although community interpreters are key to migrant women accessing social services in Australia, the profession resists calls for specialized education. This resistance occurs in a country that is recognized internationally for its progressive public service interpreting policies. We question why this is the case, and suggest that adherence to a peculiarly superficial notion of "impartiality" dulls the profession's responsiveness to the reality of male violence. We draw on government and non-governmental organization (NGO) reports, as well as interpreting scholarship using a gender lens, to theorize the need for feminist education of professional community interpreters.

  12. Gender Differences in Predictors of Self-Reported Physical Aggression: Exploring Theoretically Relevant Dimensions among Adolescents from Santiago, Chile

    PubMed Central

    Fries, Lauren; Grogan-Kaylor, Andrew; Bares, Cristina; Han, Yoonsun; Delva, Jorge

    2013-01-01

    Research findings remain unclear on whether different factors predict aggression for adolescent men and women. Given that aggression research is rarely conducted with Latin American populations, the current study used multiple imputation and linear regression to assess gender differences in levels and predictors of self-reported physical aggression among a community sample of young (ages 11 through 17) men (n=504) and women (n = 471) from Santiago, Chile. Results revealed that adolescent women reported engaging in higher levels of physical aggression than men. The variables found to be significantly associated with higher levels of reported aggression—younger age, less family involvement, less parental control, less positive relationships with caregivers, having more friends who act out and use substances, having fewer friends committed to learning, presence of dating violence, and more exposure to neighborhood crime—were not moderated by gender, implying that similar factors are related to aggression in adolescent men and women from Chile. Implications for prevention and intervention efforts to address high-risk adolescents and reduce aggression among Chilean youth are discussed. PMID:24392266

  13. Gender Differences in Predictors of Self-Reported Physical Aggression: Exploring Theoretically Relevant Dimensions among Adolescents from Santiago, Chile.

    PubMed

    Fries, Lauren; Grogan-Kaylor, Andrew; Bares, Cristina; Han, Yoonsun; Delva, Jorge

    2013-10-01

    Research findings remain unclear on whether different factors predict aggression for adolescent men and women. Given that aggression research is rarely conducted with Latin American populations, the current study used multiple imputation and linear regression to assess gender differences in levels and predictors of self-reported physical aggression among a community sample of young (ages 11 through 17) men (n=504) and women (n = 471) from Santiago, Chile. Results revealed that adolescent women reported engaging in higher levels of physical aggression than men. The variables found to be significantly associated with higher levels of reported aggression-younger age, less family involvement, less parental control, less positive relationships with caregivers, having more friends who act out and use substances, having fewer friends committed to learning, presence of dating violence, and more exposure to neighborhood crime-were not moderated by gender, implying that similar factors are related to aggression in adolescent men and women from Chile. Implications for prevention and intervention efforts to address high-risk adolescents and reduce aggression among Chilean youth are discussed.

  14. Collective dynamics of glass-forming polymers at intermediate length scales . A synergetic combination of neutron scattering, atomistic simulations and theoretical modelling

    NASA Astrophysics Data System (ADS)

    Colmenero, Juan; Alvarez, Fernando; Arbe, Arantxa

    2015-01-01

    Motivated by the proposition of a new theoretical ansatz [V.N. Novikov, K.S. Schweizer, A.P. Sokolov, J. Chem. Phys. 138, 164508 (2013)], we have revisited the question of the characterization of the collective response of polyisobutylene at intermediate length scales observed by neutron spin echo (NSE) experiments. The model, generalized for sublinear diffusion -as it is the case of glass-forming polymers- has been successfully applied by using the information on the total self-motions available from MD-simulations properly validated by direct comparison with experimental results. From the fits of the coherent NSE data, the collective time at Q → 0 has been extracted that agrees very well with compiled results from different experimental techniques directly accessing such relaxation time. We show that a unique temperature dependence governs both, the Q → 0 and Q →∞ asymptotic characteristic times. The generalized model also gives account for the modulation of the apparent activation energy of the collective times with the static structure factor. It mainly results from changes of the short-range order at inter-molecular length scales.

  15. Theoretical Implications of Gender, Power, and Sexual Scripts for HIV Prevention Programs Aimed at Young, Substance-Using African-American Women.

    PubMed

    Hill, Mandy; Granado, Misha; Stotts, Angela

    2016-12-15

    HIV continues to be a major public health problem for African-American (AA) women, and the burden of new cases to our society is significant because each case is at risk of infecting others. Substance use worsens the risk of HIV transmission to AA women. We provide specific recommendations to move the concept of tailoring HIV prevention interventions for substance users forward by focusing on young, sexually active, substance-using AA women and applying a culturally relevant revision to existing theoretical frameworks to include the Sexual Script Theory and the Theory of Gender and Power. We encourage use of these theories to guide adaptation of interventions to demonstrate efficacy within this hard-to-reach population. Consistent use of theories designed to exploit powerlessness and sexual scripts as barriers to adoption of protective sexual behaviors has potential to permeate sexual and substance use networks among African-Americans. This recommendation is being made because this theoretical framework has not been used in HIV prevention interventions targeting young, sexually active, substance-using AA women.

  16. Gender Beliefs and Embedded Gendered Values in Preschool

    ERIC Educational Resources Information Center

    Emilson, Anette; Folkesson, Anne-Mari; Lindberg, Ingeborg Moqvist

    2016-01-01

    The aim of this study is to explore practitioners' gender beliefs and how gendered values are embedded in Swedish preschool practice. The research question is: What beliefs about gender and the associated values, can be identified in practitioners' talk when they discuss gender issues? The study is informed by Bronwyn Davies' theoretical ideas…

  17. Gender Beliefs and Embedded Gendered Values in Preschool

    ERIC Educational Resources Information Center

    Emilson, Anette; Folkesson, Anne-Mari; Lindberg, Ingeborg Moqvist

    2016-01-01

    The aim of this study is to explore practitioners' gender beliefs and how gendered values are embedded in Swedish preschool practice. The research question is: What beliefs about gender and the associated values, can be identified in practitioners' talk when they discuss gender issues? The study is informed by Bronwyn Davies' theoretical ideas…

  18. Theoretical studies on the electronic structure and properties of complex ceramic crystals and glasses. Annual progress report, July 1, 1991--June 30, 1992

    SciTech Connect

    Ching, Wai-Yim

    1991-01-24

    This progress report summarizes the accomplishment of the DOE-support research program at the University of Missouri-Kansas City for the period July 1, 1991--June 30, 1992. This is the second year of a three-year renewal. The major accomplishments for the year are: (a) Initiation of fundamental studies on the electronic properties of C{sub 60} and related crystals; (b) study of electronic structures and optical properties of several important ceramic crystals, especially on AlN, SiO{sub 2} and Al{sub 2}O{sub 3}; (c) first-principles calculation of total energies and structural phase transitions in oxides, nitrides, and borides; (d) theory of magnetism in Nd{sub 2}Fe{sub 14}B permanent magnetic alloy. The major focus for the next year`s effort will be on the following areas: (1) Continuation of the fundamental studies on the buckminsterfullerene system with particular emphasis on the alkali-doped superconducting fullerides. (2) Fundamental studies on the structure and properties of Boron and B-related compounds. (3) Basic studies on the structural and electronic properties of metallic glasses with particular emphasis on the magnetic glasses. (4) Further development of the first-principles OLCAO method for applications to super-complex systems.

  19. Theoretical Considerations of the Prigogine-Defay Ration with Regard to the Glass-Forming Ability of Drugs from Undercooled Melts

    SciTech Connect

    Wyttenbach, Nicole; Kirchmeyer, Wiebke; Alsenz, Jochem; Kuentz, Martin

    2016-01-26

    Drug behavior in undercooled melts is highly important for pharmaceutics with regard to amorphous solid dispersions, and therefore, categories were recently introduced that differentiate glass formers (GFs) from other drugs that are nonglass formers (nGFs). The present study is based on the assumption that molecular properties relevant for the so-called Prigogine–Defay (PD) ratio would be indicative of a drug’s glass-forming ability. The PD ratio depends in theory on the entropy of fusion and molar volume. Experimental data were gathered from a broad set of pharmaceutical compounds (n = 54) using differential scanning calorimetry. The obtained entropy of fusion and molar volume were indeed found to significantly discriminate GFs from nGFs. In a next step, the entropy of fusion was predicted by different in silico methods. A first group contribution method provided rather unreliable estimates for the entropy of fusion, while an alternative in silico approach seemed more promising for drug categorization. Thus, a significant discrimination model employed molar volume, a so-called effective hydrogen bond number, and effective number of torsional bonds (or torsional units) to categorize GFs and nGFs (p ≤ 0.0000). The results led to new insights into drug vitrification and to practical rules of thumb. The latter may serve as guidance in pharmaceutical profiling and early formulation development with respect to amorphous drug formulations.

  20. Through the Magnifying Glass: A Descriptive Theoretical Analysis of the Possible Impact of the South African Higher Education Policies on Academic Staff and their Job Satisfaction

    ERIC Educational Resources Information Center

    Mapesela, Mabokang; Hay, H. R.

    2005-01-01

    This article provides a descriptive theoretical analysis of the most important higher education policies and initiatives which were developed by the democratically elected government of South Africa after 1994 to transform the South African higher education system. The article sheds light on the rationale for the policies under scrutiny; how they…

  1. Glass sealing

    SciTech Connect

    Brow, R.K.; Kovacic, L.; Chambers, R.S.

    1996-04-01

    Hernetic glass sealing technologies developed for weapons component applications can be utilized for the design and manufacture of fuel cells. Design and processing of of a seal are optimized through an integrated approach based on glass composition research, finite element analysis, and sealing process definition. Glass sealing procedures are selected to accommodate the limits imposed by glass composition and predicted calculations.

  2. Realization of a Zachariasen glass

    NASA Astrophysics Data System (ADS)

    Phillips, J. C.

    1983-07-01

    Recent experimental and theoretical studies of oxide and chalcogenide network glasses have shown that their molecular structure is predominantly that of a frozen liquid of partially polymerized clusters. The formation of continuous random networks is predicted at critical compositions by the topological theory of network glass formation. The predicted compositions are in good agreement with recent data on Sn xGe 1- x(S or Se) 2 ternary chalcogenide glass alloys.

  3. Theoretical calculations of spin-Hamiltonian parameters for the (MoOX5)2- (X=Cl, Br) metallic complexes in solution or frozen-glass

    NASA Astrophysics Data System (ADS)

    Mei, Yang; Zheng, Wen-Chen; Zhang, Lin; Chen, Bo-Wei

    2014-11-01

    The spin-Hamiltonian parameters (g factors g//, g⊥ and hyperfine structure constants A//, A⊥) of the (MoOX5)2- (X=Cl, Br) metallic complexes in solution or frozen-glass are calculated from the high-order perturbation formulas based on the two-mechanism model. In these formulas, the contributions to spin-Hamiltonian parameters due to both the widely-applied crystal-field (CF) mechanism and the charge-transfer (CT) mechanism (which is neglected in CF theory) are taken into account, and the needed CF and CT energy levels are obtained from the optical spectra. The calculated results with two adjustable parameters are in reasonable agreement with the experimental values. The calculations show that (i) the relative importance of CT mechanism in (MoOBr5)2- metallic complexes is larger than that in (MoOCl5)2- ones because of the stronger covalence of Mo5+-Br- combination, and (ii) in both (MoOCl5)2- and (MoOBr5)2- metallic complexes, the contributions to spin-Hamiltonian parameters due to CT mechanism should also be taken into account because of the high valence state of Mo5+ ion.

  4. Theoretical prediction of Grüneisen parameter for SiO{sub 2}.TiO{sub 2} bulk metallic glasses

    SciTech Connect

    Singh, Chandra K.; Pandey, Brijesh K.; Pandey, Anjani K.

    2016-05-23

    The Grüneisen parameter (γ) is very important to decide the limitations for the prediction of thermoelastic properties of bulk metallic glasses. It can be defined in terms of microscopic and macroscopic parameters of the material in which former is based on vibrational frequencies of atoms in the material while later is closely related to its thermodynamic properties. Different formulation and equation of states are used by the pioneer researchers of this field to predict the true sense of Gruneisen parameter for BMG but for SiO{sub 2}.TiO{sub 2} very few and insufficient information is available till now. In the present work we have tested the validity of two different isothermal EOS viz. Poirrior-Tarantola EOS and Usual-Tait EOS to predict the true value of Gruneisen parameter for SiO{sub 2}.TiO{sub 2} as a function of compression. Using different thermodynamic limitations related to the material constraints and analyzing obtained result it is concluded that the Poirrior-Tarantola EOS gives better numeric values of Grüneisen parameter (γ) for SiO{sub 2}.TiO{sub 2} BMG.

  5. An ecofeminist conceptual framework to explore gendered environmental health inequities in urban settings and to inform healthy public policy.

    PubMed

    Chircop, Andrea

    2008-06-01

    This theoretical exploration is an attempt to conceptualize the link between gender and urban environmental health. The proposed ecofeminist framework enables an understanding of the link between the urban physical and social environments and health inequities mediated by gender and socioeconomic status. This framework is proposed as a theoretical magnifying glass to reveal the underlying logic that connects environmental exploitation on the one hand, and gendered health inequities on the other. Ecofeminism has the potential to reveal an inherent, normative conceptual analysis and argumentative justification of western society that permits the oppression of women and the exploitation of the environment. This insight will contribute to a better understanding of the mechanisms underlying gendered environmental health inequities and inform healthy public policy that is supportive of urban environmental health, particularly for low-income mothers.

  6. Covalent Assembled Monolayers of Homo- and Heteroleptic Fe(II)-Terpyridyl Complexes on SiOx and ITO-Coated Glass Substrates: An Experimental and Theoretical Study.

    PubMed

    Mondal, Dr Prakash Chandra; Singh, Vikram; Manna, Arun K; Zharnikov, Michael

    2017-09-14

    Well-defined Fe(II)-terpyridyl monolayers were fabricated on SiOx and conductive ITO-coated glass substrates via covalent bond formation between the metallo-organic complexes and a pre-assembled coupling layer. Three different homo- and heteroleptic complexes with the terminal pyridyl, amine, and phenyl groups were tested. All the films were found to be densely packed, homogeneous, and consisting of upright standing molecules. They exhibited high thermal (up to ~220°C) and temporal (up to 5h at 100°C) stability. The UV-vis spectra of the monolayers showed a pronounced metal-to-ligand charge-transfer bands with a significant red-shift as compared to the solution spectra of the respective metallo-ligands in the case of pendant pyridyl group quaternized with the coupling layer, while the shift was significantly smaller when the coupling layer was bonded to the primary amine (NH2) group of the complex. The cyclic voltammograms of the monolayers showed reversible, one-electron redox behavior and suggested strong electronic coupling between the confined molecules and the underlying substrate. The analysis of the electrochemistry data allowed also to estimate the charge-transfer rate constant between the metal centre and the substrate. Additionally, detailed quantum chemical calculations were performed to support and rationalize the experimentally observed photophysical properties of the Fe(II)-terpyridyl complexes both in solution state and bound to a SiOx-based substrate. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. [Glass ceiling and slippery stairs? Gender inequalities and strategies for change in the Spanish Society of Public Health and Health Services Administration].

    PubMed

    Colomer Revuelta, C; Peiró Pérez, R

    2002-01-01

    In scientific societies, as in other social fields, women's participation in decision making is lower than that of men. We describe the situation in SESPAS (Spanish Society of Public Health and Health Services Administration) where, despite representing a 40% of its members, very few women have been in positions in which decisions are taken or in those of professional recognition. The process of change implemented during recent years and some of the effects of the actions taken are presented. Making the existing inequalities known has generated debate and interest in the intervention. A gender and public health working group was set up. In the last two years more women have been promoted to more senior positions in SESPAS.

  8. Mixed polyanion glass cathodes: Iron phosphate vanadate glasses

    SciTech Connect

    Kercher, Andrew K; Ramey, Joanne Oxendine; Carroll, Kyler J; Kiggans Jr, James O; Veith, Gabriel M; Meisner, Roberta; Boatner, Lynn A; Dudney, Nancy J

    2014-01-01

    Mixed polyanion (MP) glasses have been investigated for use as cathodes in lithium ion batteries. MP glass cathodes are similar in composition to theoretically promising crystalline polyanionic (CP) cathodes (e.g., lithium cobalt phosphate, lithium manganese silicate), but with proper polyanion substitution, they can be designed to overcome the key shortcomings of CP cathodes, such as poor electrical conductivity and irreversible phase changes. Iron phosphate/vanadate glasses were chosen as a first demonstration of the MP glass concept. Polyanion substitution with vanadate was shown to improve the intercalation capacity of an iron phosphate glass from almost zero to full theoretical capacity. In addition, the MP glass cathodes also exhibited an unexpected second high-capacity electrochemical reaction. X-ray absorption near-edge structure (XANES) and x-ray diffraction (XRD) of cathodes from cells having different states of charge suggested that this second electrochemical reaction is a glass-state conversion reaction. With a first demonstration established, MP glass materials utilizing an intercalation and/or glass-state conversion reaction are promising candidates for future high-energy cathode research.

  9. Glass recycling

    SciTech Connect

    Dalmijn, W.L.; Houwelingen, J.A. van

    1995-12-31

    Glass recycling in the Netherlands has grown from 10,000 to 300,000 tonnes per annum. The various advantages and problems of the glass cycle with reference to the state of the art in the Netherlands is given. Special attention is given to new technologies for the automated sorting of cullet with detection systems. In Western Europe the recycling of glass has become a success story. Because of this, the percentage of glass cullet used in glass furnaces has increased. To meet the quality demands of the glass industry, automated sorting for the removal of stones, non-ferrous metals and other impurities had to be developed and incorporated in glass recycling plants. In Holland, Germany and other countries, the amount of glass collected has reached a level that color-sorting becomes necessary to avoid market saturation with mixed cullet. Recently, two systems for color-sorting have been developed and tested for the separation of bottles and cullet in the size range of 20--50 mm. With the increased capacity of the new glass recycling plants, 120,000--200,000 tpy, the quality systems have also to be improved and automated. These quality control systems are based on the automated sorting technology developed earlier for the glass recycling plants. The data obtained are automatically processed and printed. The sampling system and its relation to the theory of Gy will be described. Results of both developments in glass recycling plants will be described.

  10. Glass Artworks

    NASA Technical Reports Server (NTRS)

    1988-01-01

    Several NASA technologies have played part in growth and cost containment of studio glass art, among them a foam type insulation developed to meet a need for lightweight material that would reduce flame spread in aircraft fire. Foam comes in several forms and is widely used by glass artists, chiefly as an insulator for the various types of ovens used in glass working. Another Spinoff is alumina crucibles to contain molten glass. Before alumina crucibles were used, glass tanks were made of firebrick which tended to erode under high temperatures and cause impurities; this not only improved quality but made the process more cost effective. One more NASA technology that found its way into glass art working is a material known as graphite board, a special form of graphite originally developed for rocket motor applications. This graphite is used to exact compound angles and creates molds for poured glass artworks of dramatic design.

  11. Patterns of Gender Development

    PubMed Central

    Martin, Carol Lynn; Ruble, Diane N.

    2013-01-01

    A comprehensive theory of gender development must describe and explain long-term developmental patterning and changes and how gender is experienced in the short term. This review considers multiple views on gender patterning, illustrated with contemporary research. First, because developmental research involves understanding normative patterns of change with age, several theoretically important topics illustrate gender development: how children come to recognize gender distinctions and understand stereotypes, and the emergence of prejudice and sexism. Second, developmental researchers study the stability of individual differences over time, which elucidates developmental processes. We review stability in two domains—sex segregation and activities/interests. Finally, a new approach advances understanding of developmental patterns, based on dynamic systems theory. Dynamic systems theory is a metatheoretical framework for studying stability and change, which developed from the study of complex and nonlinear systems in physics and mathematics. Some major features and examples show how dynamic approaches have been and could be applied in studying gender development. PMID:19575615

  12. Gain saturation in neodymium glasses

    NASA Astrophysics Data System (ADS)

    Brodov, M. E.; Epatko, I. V.; Ivanov, A. V.; Pashinin, P. P.; Serov, R. V.

    1987-12-01

    A theoretical model of gain saturation in Nd glasses is chosen which is based on minimum standard deviation from experimental data. It is shown that the laser-active-medium parameters cannot be determined effectively using this minimization. The possibility of using multipass schemes to choose the theoretical model is assessed.

  13. Glass Research

    NASA Technical Reports Server (NTRS)

    Weinberg, M. C.

    1985-01-01

    Research efforts span three general areas of glass science: glass refining, gel-derived glasses, and nucleation and crystallization of glasses. Gas bubbles which are present in a glass product are defects which may render the glass totally useless for the end application. For example, optical glasses, laser host glasses, and a variety of other specialty glasses must be prepared virtually defect free to be employable. Since a major mechanism of bubble removal, buoyant rise, is virtually inoperative in microgravity, glass fining will be especially difficult in space. On the other hand, the suppression of buoyant rise and the ability to perform containerless melting experiments in space allows the opportunity to carry out several unique bubble experiments in space. Gas bubble dissolution studies may be performed at elevated temperatures for large bubbles with negligible bubble motion. Also, bubble nucleation studies may be performed without the disturbing feature of heterogeneous bubble nucleation at the platinum walls. Ground based research efforts are being performed in support of these potential flight experiments.

  14. GENDERED CHALLENGE, GENDERED RESPONSE

    PubMed Central

    KELLY, ERIN L.; AMMONS, SAMANTHA K.; CHERMACK, KELLY; MOEN, PHYLLIS

    2010-01-01

    This article integrates research on gendered organizations and the work-family interface to investigate an innovative workplace initiative, the Results-Only Work Environment (ROWE), implemented in the corporate headquarters of Best Buy, Inc. While flexible work policies common in other organizations “accommodate” individuals, this initiative attempts a broader and deeper critique of the organizational culture. We address two research questions: How does this initiative attempt to change the masculinized ideal worker norm? And what do women's and men's responses reveal about the persistent ways that gender structures work and family life? Data demonstrate the ideal worker norm is pervasive and powerful, even as employees begin critically examining expectations regarding work time that have historically privileged men. Employees' responses to ROWE are also gendered. Women (especially mothers) are more enthusiastic, while men are more cautious. Ambivalence about and resistance to change is expressed in different ways depending on gender and occupational status. PMID:20625518

  15. Child maltreatment, parent alcohol and drug-related problems, polydrug problems, and parenting practices: a test of gender differences and four theoretical perspectives.

    PubMed

    Locke, Thomas F; Newcomb, Michael

    2004-03-01

    The authors tested how adverse childhood experiences (child maltreatment and parent alcohol- and drug-related problems) and adult polydrug use (as a mediator) predict poor parenting in a community sample (237 mothers and 81 fathers). These relationships were framed within several theoretical perspectives, including observational learning, impaired functioning, self-medication, and parentification-pseudomaturity. Structural models revealed that child maltreatment predicted poor parenting practices among mothers. Parent alcohol- and drug-related problems had an indirect detrimental influence on mothers' parenting and practices through self-drug problems. Among fathers, emotional neglect experienced as a child predicted lack of parental warmth more parental neglect, and sexual abuse experienced as a child predicted a rejecting style of parenting.

  16. Dynamics of Glass Relaxation at Room Temperature

    NASA Astrophysics Data System (ADS)

    Welch, Roger C.; Smith, John R.; Potuzak, Marcel; Guo, Xiaoju; Bowden, Bradley F.; Kiczenski, T. J.; Allan, Douglas C.; King, Ellyn A.; Ellison, Adam J.; Mauro, John C.

    2013-06-01

    The problem of glass relaxation under ambient conditions has intrigued scientists and the general public for centuries, most notably in the legend of flowing cathedral glass windows. Here we report quantitative measurement of glass relaxation at room temperature. We find that Corning® Gorilla® Glass shows measurable and reproducible relaxation at room temperature. Remarkably, this relaxation follows a stretched exponential decay rather than simple exponential relaxation, and the value of the stretching exponent (β=3/7) follows a theoretical prediction made by Phillips for homogeneous glasses.

  17. GLASS FIBER REINFORCED PLASTICS,

    DTIC Science & Technology

    Contents: Fibrous glass fillers Binders used in the glass plastic industry Method of manufacturing glass plastics and glass plastic articles Properties of fiberglass Primary areas for use of glass fibre reinforced plastics

  18. Tempered glass

    SciTech Connect

    Bunnell, L.R.

    1991-11-01

    This document describes a demonstration for making tempered glass using minimal equipment. The demonstration is intended for a typical student of materials science, at the high school level or above. (JL)

  19. Electrochromic Glasses.

    DTIC Science & Technology

    1980-07-31

    composition where nuclear magnetic resonance, infrared and Raman spectra show a possible charge in the coordination of B. All the "borate anamolies " also...34pseudo-spins" in an amorphous matrix behaves in many ways as the elec- tric analogue of a magnetic spin glass system. We developed a model for a...boric oxide is used extensively in borosilicate glasses. An extensive body of literature utilizing nuclear magnetic resonance, infrared and Raman

  20. Gendered Performances during Peer Revision

    ERIC Educational Resources Information Center

    Styslinger, Mary E.

    2008-01-01

    This study explored the ways gender is accomplished in varied social contexts during the peer revision process in a secondary English classroom. Using a post-structural feminist theoretical framework, an analysis of classroom discourse provided a basis for understanding the performance of gender during peer revision, the effects of gender…

  1. Entropy Crises in Glasses and Random Heteropolymers.

    PubMed

    Wolynes, Peter G

    1997-01-01

    The concept of random first order transitions with configurational entropy crises provides a theoretical framework for understanding the glass transition. This paper discusses such transitions in exactly solvable spin glass models and in globular random heteropolymers and their relation to glass transitions in molecular fluids and polymers. The Vogel-Fulcher law is shown to be related to the search time through the energy landscape of an "entropic droplet."

  2. Pinhole Glasses

    NASA Astrophysics Data System (ADS)

    Colicchia, Giuseppe; Hopf, Martin; Wiesner, Hartmut; Zollman, Dean

    2008-01-01

    Eye aberrations are commonly corrected by lenses that restore vision by altering rays before they pass through the cornea. Some modern promoters claim that pinhole glasses are better than conventional lenses in correcting all kinds of refractive defects such as myopia (nearsighted), hyperopia (farsighted), astigmatisms, and presbyopia. Do pinhole glasses really give better vision? Some ways to use this question for motivation in teaching optics have been discussed. For this column we include a series of experiments that students can complete using a model of the eye and demonstrate issues related to pinhole vision correction.

  3. Pinhole Glasses

    ERIC Educational Resources Information Center

    Colicchia, Giuseppe; Hopf, Martin; Wiesner, Hartmut; Zollman, Dean

    2008-01-01

    Eye aberrations are commonly corrected by lenses that restore vision by altering rays before they pass through the cornea. Some modern promoters claim that pinhole glasses are better than conventional lenses in correcting all kinds of refractive defects such as myopia (nearsighted), hyperopia (farsighted), astigmatisms, and presbyopia. Do pinhole…

  4. Pinhole Glasses

    ERIC Educational Resources Information Center

    Colicchia, Giuseppe; Hopf, Martin; Wiesner, Hartmut; Zollman, Dean

    2008-01-01

    Eye aberrations are commonly corrected by lenses that restore vision by altering rays before they pass through the cornea. Some modern promoters claim that pinhole glasses are better than conventional lenses in correcting all kinds of refractive defects such as myopia (nearsighted), hyperopia (farsighted), astigmatisms, and presbyopia. Do pinhole…

  5. Prediction of glass durability as a function of glass composition and test conditions: Thermodynamics and kinetics

    SciTech Connect

    Jantzen, C M

    1988-01-01

    The long-term durability of nuclear waste glasses can be predicted by comparing their performance to natural and ancient glasses. Glass durability is a function of the kinetic and thermodynamic stability of glass in solution. The relationship between the kinetic and thermodynamic aspects of glass durability can be understood when the relative contributions of glass composition and imposed test conditions are delineated. Glass durability has been shown to be a function of the thermodynamic hydration free energy which can be calculated from the glass composition. Hydration thermodynamics also furnishes a quantitative frame of reference to understand how various test parameters affect glass durability. Linear relationships have been determined between the logarithmic extent of hydration and the calculated hydration free energy for several different test geometries. Different test conditions result in different kinetic reactivity parameters such as the exposed glass surface area (SA), the leachant solution volume (V), and the length of time that the glass is in the leachant (t). Leachate concentrations are known to be a function of the kinetic test parameter (SAV)t. The relative durabilities of glasses, including pure silica, obsidians, nuclear waste glasses, medieval window glasses, and frit glasses define a plane in three dimensional ..delta..G/sub hyd/-concentration-(SAV)t space. At constant kinetic conditions, e.g., test geometry and test duration, the three dimensional plane is intersected at constant (SAV)t and the ..delta..G/sub hyd/-concentration plots have similar slopes. The slope represents the natural logarithm of the theoretical slope, (12.303 RT), for the rate of glass dissolution. 53 refs., 4 figs.

  6. Einblicke in "Genderism" im Schulischen Verhalten durch subjektive Reflexivitat (Insights into "Genderism" in School Behavior).

    ERIC Educational Resources Information Center

    Faulstich-Wieland; Guting, Damaris; Ebsen, Silke

    2001-01-01

    Explores gender construction through school interactions. Views gender as a socially produced category by analyzing various theoretical approaches. Develops the genderism of school conduct using two examples from German instruction stating that confusion with sexual orientation arises through the deconstruction of the assumed role and active…

  7. Explaining gender segregation.

    PubMed

    Blackburn, Robert M; Browne, Jude; Brooks, Bradley; Jarman, Jennifer

    2002-12-01

    Occupational gender segregation--the tendency for women and men to work in different occupations--is an important feature of all societies, and particularly the wealthy industrialized ones. To understand this segregation, and to explain its significance, we need to distinguish between vertical segregation entailing inequality and horizontal segregation representing difference without inequality, with overall segregation being the resultant of these components. Three major theoretical approaches to understanding occupational gender segregation are examined: human capital/rational choice, patriarchy, and preference theories. All are found to be inadequate; they tend to confuse overall segregation with its vertical component, and each entails a number of other faults. It is generally assumed or implied that greater empowerment of women would reduce gender segregation. This is the reverse of what actually happens; in countries where the degree of women's empowerment is greater, the level of gender segregation is also greater. An alternative theoretical approach based on processes of social reproduction is shown to be more useful.

  8. Multiple reentrant glass transitions in confined hard-sphere glasses

    NASA Astrophysics Data System (ADS)

    Mandal, Suvendu; Lang, Simon; Gross, Markus; Oettel, Martin; Raabe, Dierk; Franosch, Thomas; Varnik, Fathollah

    2014-07-01

    Glass-forming liquids exhibit a rich phenomenology upon confinement. This is often related to the effects arising from wall-fluid interactions. Here we focus on the interesting limit where the separation of the confining walls becomes of the order of a few particle diameters. For a moderately polydisperse, densely packed hard-sphere fluid confined between two smooth hard walls, we show via event-driven molecular dynamics simulations the emergence of a multiple reentrant glass transition scenario upon a variation of the wall separation. Using thermodynamic relations, this reentrant phenomenon is shown to persist also under constant chemical potential. This allows straightforward experimental investigation and opens the way to a variety of applications in micro- and nanotechnology, where channel dimensions are comparable to the size of the contained particles. The results are in line with theoretical predictions obtained by a combination of density functional theory and the mode-coupling theory of the glass transition.

  9. Gender Imputation

    ERIC Educational Resources Information Center

    National Student Clearinghouse, 2013

    2013-01-01

    In late 2007, the National Student Clearinghouse (NSC) expanded its Enrollment Reporting service to include several additional data elements (commonly referred to as the "A2" or "expanded" data elements). One of these expanded data elements is student gender. Although gender is potentially important to a number of research…

  10. Gender Development

    ERIC Educational Resources Information Center

    Owen Blakemore, Judith E.; Berenbaum, Sheri A.; Liben, Lynn S.

    2008-01-01

    This new text offers a unique developmental focus on gender. Gender development is examined from infancy through adolescence, integrating biological, socialization, and cognitive perspectives. The book's current empirical focus is complemented by a lively and readable style that includes anecdotes about children's everyday experiences. The book's…

  11. Gender Fictions.

    ERIC Educational Resources Information Center

    Lee, Lesley

    1992-01-01

    Reviews and compares "Gender and Mathematics" edited by Leone Burton and Valerie Walkerdine's book "Schoolgirl Fictions" on proposed truths related to gender issues in mathematics. Issues include (1) attention given to boys and girls in mathematics class; (2) the effects of noncompetitive classroom environments; and (3) sex differences in…

  12. Gender Advertisements.

    ERIC Educational Resources Information Center

    Goffman, Erving

    A heavily illustrated discussion of the ways in which men and women are portrayed in advertisements is presented. The three essays which precede the 56 pages of illustrations discuss gender expressions, characteristics of public and private pictures, and gender commercials. The author notes that advertisements do not depict how men and women…

  13. On Gender.

    ERIC Educational Resources Information Center

    Wilson, James Q.

    1993-01-01

    Explores differences between males and females and their manifestation in biology and culture. Cultures differ, not in whether they cope with the socialization of males to invest in child rearing, but in how they deal with this problem. Issues of gender and power and gender and child rearing are discussed. (SLD)

  14. Gender equity.

    PubMed

    Shiva, M

    1999-01-01

    This paper focuses on gender equity. Gender equity is difficult to achieve when there is no economic, social, or political equity. The Gender Development Index evidenced this. There were a lot of instances where women are psychologically traumatized, whether it is through domestic rape, purchased sexual services in the red light area, and seduction or violation of neighbors, relatives, daughter or child. The economic changes linked with globalization and media's influence have worsened women's position. The policy for empowerment of women is an attempt toward ensuring equity. Furthermore, many women and women's organizations are trying to address these inequities; wherein they fight for strong acceptance of women's rights, social, economic, and political rights, as well as equities between gender and within gender.

  15. Data, Methods, and Theoretical Implications

    ERIC Educational Resources Information Center

    Hannagan, Rebecca J.; Schneider, Monica C.; Greenlee, Jill S.

    2012-01-01

    Within the subfields of political psychology and the study of gender, the introduction of new data collection efforts, methodologies, and theoretical approaches are transforming our understandings of these two fields and the places at which they intersect. In this article we present an overview of the research that was presented at a National…

  16. Data, Methods, and Theoretical Implications

    ERIC Educational Resources Information Center

    Hannagan, Rebecca J.; Schneider, Monica C.; Greenlee, Jill S.

    2012-01-01

    Within the subfields of political psychology and the study of gender, the introduction of new data collection efforts, methodologies, and theoretical approaches are transforming our understandings of these two fields and the places at which they intersect. In this article we present an overview of the research that was presented at a National…

  17. GlassForm

    SciTech Connect

    2011-09-16

    GlassForm is a software tool for generating preliminary waste glass formulas for a given waste stream. The software is useful because it reduces the number of verification melts required to develop a suitable additive composition. The software includes property models that calculate glass properties of interest from the chemical composition of the waste glass. The software includes property models for glass viscosity, electrical conductivity, glass transition temperature, and leach resistance as measured by the 7-day product consistency test (PCT).

  18. Characteristic length of glass transition

    NASA Astrophysics Data System (ADS)

    Donth, E.

    1996-03-01

    The characteristic length of the glass transition (ξ _α ) is based on the concept of cooperatively rearranging regions (CRR's) by Adam & Gibbs (1965): ξ _α is the diameter of one CRR. In the theoretical part of the talk a formula is derived how this length can be calculated from calorimetric data of the transformation interval. The approach is based on fluctuations in natural functional subsystems. The corresponding thermodynamics is represented e.g. in a book of the author (E. Donth, Relaxation and Thermodynamics in Polymers. Glass Transition, Akademie-Verlag, Berlin 1992). A typical value for this length is 3 nanometers. In the experimental part several examples are reported to enlarge the experimental evidence for such a length: Squeezing the glass transition in the amorphous layers of partially crystallized PET (C. Schick, Rostock), glass transition of small-molecule glass formers in a series of nanoscaled pores of porous glasses (F. Kremer, Leipzig), comparison with a concentration fluctuation model in homogeneous polymer mixtures (E.W. Fischer, Mainz), and, from our laboratory, backscaling to ξ _α across the main transition from the entanglement spacing in several amorphous polymers such as PVAC, PS, NR, and some polymer networks. Rouse backscaling was possible in the α β splitting region of several poly(n alkyl methacrylates) resulting in small characteristic lengths of order 1 nanometer near the onset of α cooperativity. In a speculative outlook a dynamic density pattern is presented, having a cellular structure with higher density and lower mobility of the cell walls. It will be explained, with the aid of different thermal expansion of wall and clusters, how the clusters within the cells maintain a certain mobility far below the glass temperature.

  19. Impact Strength of Glass and Glass Ceramic

    NASA Astrophysics Data System (ADS)

    Bless, Stephan; Tolman, John

    2009-06-01

    Bar impact tests, using the techniques described elsewhere in this symposium, were used to measure compressive and tensile strengths of borosilicate glass, soda lime glass, and glass ceramic. The glass ceramic was 25% crystalline spinel, furnished by Corning, Inc. There are two measures of compressive strength: the peak stress that can be transmitted in unconfined compression and the steady-state strength. For both glasses, these values were similar, being about 1.8 and 1.5 GPa, respectively. The glass ceramic was almost 50% stronger. Tensile failure in the glass and glass ceramic takes places via surface flaws, and thus tensile strength is an extrinsic---as opposed to intrinsic---property.

  20. Strength of inorganic glass

    SciTech Connect

    Kurkjian, C.R.

    1985-01-01

    This book presents information on the following topics: a look at the history of glass strength; atomistic theory of fracture; surface chemistry in relation to the strength and fracture of silicate glasses; high-speed photographic investigations of the dynamic localized loading of some oxide glasses; a correction for measurements of contact area using Newton's rings; envionmentally enhanced crack growth; fatigue in glass; behavior of flaws in fused silica fibers; fracture toughness of chalcogenide glasses and glass-ceramics; fracture analysis of glass surfaces; and fracture mechanics parameters for glasses - a compilation and correlation.

  1. CRYSTALLIZATION IN MULTICOMPONENT GLASSES

    SciTech Connect

    KRUGER AA; HRMA PR

    2009-10-08

    In glass processing situations involving glass crystallization, various crystalline forms nucleate, grow, and dissolve, typically in a nonuniform temperature field of molten glass subjected to convection. Nuclear waste glasses are remarkable examples of multicomponent vitrified mixtures involving partial crystallization. In the glass melter, crystals form and dissolve during batch-to-glass conversion, melter processing, and product cooling. Crystals often agglomerate and sink, and they may settle at the melter bottom. Within the body of cooling glass, multiple phases crystallize in a non-uniform time-dependent temperature field. Self-organizing periodic distribution (the Liesegnang effect) is common. Various crystallization phenomena that occur in glass making are reviewed.

  2. Orbital glass and spin glass states of 3He-A in aerogel

    NASA Astrophysics Data System (ADS)

    Dmitriev, V. V.; Krasnikhin, D. A.; Mulders, N.; Senin, A. A.; Volovik, G. E.; Yudin, A. N.

    2010-06-01

    Glass states of superfluid A-like phase of 3He in aerogel induced by random orientations of aerogel strands are investigated theoretically and experimentally. In anisotropic aerogel with stretching deformation two glass phases are observed. Both phases represent the anisotropic glass of the orbital ferromagnetic vector Ηthe orbital glass (OG). The phases differ by the spin structure: the spin nematic vector hat d can be either in the ordered spin nematic (SN) state or in the disordered spin-glass (SG) state. The first phase (OG-SN) is formed under conventional cooling from normal 3He. The second phase (OG-SG) is metastable, being obtained by cooling through the superfluid transition temperature, when large enough resonant continuous radio-frequency excitation is applied. NMR signature of different phases allows us to measure the parameter of the global anisotropy of the orbital glass induced by deformation.

  3. IMPACT STRENGTH OF GLASS AND GLASS CERAMIC

    SciTech Connect

    Bless, S.; Tolman, J.

    2009-12-28

    Strength of glass and glass ceramic was measured with a bar impact technique. High-speed movies show regions of tensile and compressive failure. The borosilicate glass had a compressive strength of at least 2.2 GPa, and the glass ceramic at least 4 GPa. However, the BSG was much stronger in tension than GC. In ballistic tests, the BSG was the superior armor.

  4. Diversity, culture and the glass ceiling.

    PubMed

    Wilson, Eleanor

    2014-01-01

    A reference to the term, the glass ceiling, has come to embody more than gender equality among women and men. Today the term embraces the quest of all minorities and their journey towards equality in the workplace. The purpose of this article is to bring attention to the subject of diversity, culture, and the glass ceiling. The article will discuss the history of the glass ceiling and how its broadened meaning is relevant in today's workplace. It will also provide statistics showing how diversity and culture are lacking among the top echelon of today's executives, the barriers faced by minorities as they journey towards executive leadership, and how to overcome these barriers to truly shatter the glass ceiling.

  5. A simple method for tuning the glass transition process in inorganic phosphate glasses

    PubMed Central

    Fulchiron, René; Belyamani, Imane; Otaigbe, Joshua U.; Bounor-Legaré, Véronique

    2015-01-01

    The physical modification of glass transition temperature (Tg) and properties of materials via blending is a common practice in industry and academia and has a large economic advantage. In this context, simple production of hitherto unattainable new inorganic glass blends from already existing glass compositions via blending raises much hope with the potential to provide new glasses with new and improved properties, that cannot be achieved with classical glass synthesis, for a plethora of applications such as computers screens, glass-to-metal seals, and storage materials for nuclear wastes. Here, we demonstrate that blends of the specific glass compositions studied are miscible in all proportions, an unreported phenomenon in hard condensed matter like glass. Interestingly, excellent agreement was found between the obtained data and calculated Tgs from theoretical equations (Supplementary information) for predicting the composition dependence of Tg for miscible blends with weak but significant specific interactions between the blend components. That this blending method is at present not applied to inorganic glasses reflects the fact that water and chemically resistant phosphate glasses with relatively low Tgs have become available only recently. PMID:25666949

  6. A simple method for tuning the glass transition process in inorganic phosphate glasses

    NASA Astrophysics Data System (ADS)

    Fulchiron, René; Belyamani, Imane; Otaigbe, Joshua U.; Bounor-Legaré, Véronique

    2015-02-01

    The physical modification of glass transition temperature (Tg) and properties of materials via blending is a common practice in industry and academia and has a large economic advantage. In this context, simple production of hitherto unattainable new inorganic glass blends from already existing glass compositions via blending raises much hope with the potential to provide new glasses with new and improved properties, that cannot be achieved with classical glass synthesis, for a plethora of applications such as computers screens, glass-to-metal seals, and storage materials for nuclear wastes. Here, we demonstrate that blends of the specific glass compositions studied are miscible in all proportions, an unreported phenomenon in hard condensed matter like glass. Interestingly, excellent agreement was found between the obtained data and calculated Tgs from theoretical equations (Supplementary information) for predicting the composition dependence of Tg for miscible blends with weak but significant specific interactions between the blend components. That this blending method is at present not applied to inorganic glasses reflects the fact that water and chemically resistant phosphate glasses with relatively low Tgs have become available only recently.

  7. Chemical Principles Revisited: The Chemistry of Glass.

    ERIC Educational Resources Information Center

    Kolb, Doris; Kolb, Kenneth E.

    1979-01-01

    Presents a detailed discussion on the chemistry of glass. Topics discussed include: natural glass, early history, modern glass composition, raw materials for glass melting, chemically modified glasses, modern glass forming, glass ceramics, and new developments in glass research. (BT)

  8. Chemical Principles Revisited: The Chemistry of Glass.

    ERIC Educational Resources Information Center

    Kolb, Doris; Kolb, Kenneth E.

    1979-01-01

    Presents a detailed discussion on the chemistry of glass. Topics discussed include: natural glass, early history, modern glass composition, raw materials for glass melting, chemically modified glasses, modern glass forming, glass ceramics, and new developments in glass research. (BT)

  9. Prediction of glass durability as a function of environmental conditions

    SciTech Connect

    Jantzen, C M

    1988-01-01

    A thermodynamic model of glass durability is applied to natural, ancient, and nuclear waste glasses. The durabilities of over 150 different natural and man-made glasses, including actual ancient Roman and Islamic glasses (Jalame ca. 350 AD, Nishapur 10-11th century AD and Gorgon 9-11th century AD), are compared. Glass durability is a function of the thermodynamic hydration free energy, ..delta..G/sub hyd/, which can be calculated from glass composition and solution pH. The durability of the most durable nuclear waste glasses examined was /approximately/10/sup 6/ years. The least durable waste glass formulations were comparable in durability to the most durable simulated medieval window glasses of /approximately/10/sup 3/ years. In this manner, the durability of nuclear waste glasses has been interpolated to be /approximately/10/sup 6/ years and no less than 10/sup 3/ years. Hydration thermodynamics have been shown to be applicable to the dissolution of glass in various natural environments. Groundwater-glass interactions relative to geologic disposal of nuclear waste, hydration rind dating of obsidians, andor other archeological studies can be modeled, e.g., the relative durabilities of six simulated medieval window glasses have been correctly predicted for both laboratory (one month) and burial (5 years) experiments. Effects of solution pH on glass dissolution has been determined experimentally for the 150 different glasses and can be predicted theoretically by hydration thermodynamics. The effects of solution redox on dissolution of glass matrix elements such as SI and B have shown to be minimal. The combined effects of solution pH and Eh have been described and unified by construction of thermodynamically calculated Pourbaix (pH-Eh) diagrams for glass dissolution. The Pourbaix diagrams have been quantified to describe glass dissolution as a function of environmental conditions by use of the data derived from hydration thermodynamics. 56 refs., 7 figs.

  10. Glass breaking strength: The role of surface flaws and treatments

    NASA Technical Reports Server (NTRS)

    Moore, D.

    1985-01-01

    Although the intrinsic strength of silicon dioxide glass is of the order of 10 to the 6th power lb/sq in, the practical strength is roughly two orders of magnitude below this theoretical limit, and depends almost entirely on the surface condition of the glass, that is, the number and size of flaws and the residual surface compression (temper) in the glass. Glass parts always fail in tension when these flaws grow under sustained loading to some critical size. Research associated with glass encapsulated crystalline-Si photovoltaic (PV) modules has greatly expanded our knowledge of glass breaking strength and developed sizeable data base for commercially available glass types. A detailed design algorithm is developed for thickness sizing of rectangular glass plates subject to pressure loads. Additional studies examine the strength of glass under impact loading conditions such as that caused by hail. Although the fundamentals of glass breakage are directly applicable to thin film modules, the fracture strength of typical numerical glass must be replaced with data that reflect the high temperature tin oxide processing, laser scribing, and edge processing peculiar to thin film modules. The fundamentals of glass breakage applicable to thin film modules and preliminary fracture strength data for a variety of 1 ft square glass specimens representing preprocessed and post processed sheets from current amorphous-Si module manufacturers are presented.

  11. Repairing cracked glass

    NASA Technical Reports Server (NTRS)

    Helman, D. D.; Holt, J. W.; Smiser, L. V.

    1979-01-01

    Filing procedure consisting of machined lightweight fused-silica tiles coated with thin-layer of borosilicate glass produces homogeneous seal in thin glass. Procedure is useful in repairing glass envelopes, X-ray tub windows, Dewar flasks, and similar thin glass objects.

  12. Gender and the Curriculum of Adult Education.

    ERIC Educational Resources Information Center

    Blundell, Sue

    1992-01-01

    The perspectives of four feminist discourses (liberal, radical, Marxist, and socialist) analyze the role of adult education curriculum in reinforcing gender relations. The transformation of gender relations requires a combination of radical strategies such as women-centered, women-only methodology and the theoretical framework of the…

  13. Diversity in Literary Response: Revisiting Gender Expectations

    ERIC Educational Resources Information Center

    Brendler, Beth M.

    2014-01-01

    Drawing on and reexamining theories on gender and literacy, derived from research performed between 1974 and 2002, this qualitative study explored the gender assumptions and expectations of Language Arts teachers in a graduate level adolescent literature course at a university in the Midwestern United States. The theoretical framework was…

  14. Inverted glass harp

    NASA Astrophysics Data System (ADS)

    Quinn, Daniel B.; Rosenberg, Brian J.

    2015-08-01

    We present an analytical treatment of the acoustics of liquid-filled wine glasses, or "glass harps." The solution is generalized such that under certain assumptions it reduces to previous glass harp models, but also leads to a proposed musical instrument, the "inverted glass harp," in which an empty glass is submerged in a liquid-filled basin. The versatility of the solution demonstrates that all glass harps are governed by a family of solutions to Laplace's equation around a vibrating disk. Tonal analyses of recordings for a sample glass are offered as confirmation of the scaling predictions.

  15. Chemical constraints on fly ash glass compositions

    SciTech Connect

    John H. Brindle; Michael J. McCarthy

    2006-12-15

    The major oxide content and mineralogy of 75 European fly ashes were examined, and the major element composition of the glass phase was obtained for each. Correlation of compositional trends with the glass content of the ash was explored. Alkali content was deduced to have a major influence on glass formation, and this in turn could be related to the probable chemistry of clay minerals in the source coals. Maximal glass content corresponded to high aluminum content in the glass, and this is in accordance with the theoretical mechanism of formation of aluminosilicate glasses, in which network-modifying oxides are required to promote tetrahedral coordination of aluminum in glass chain structures. Iron oxide was found to substitute for alkali oxides where the latter were deficient, and some indications of preferred eutectic compositions were found. The work suggests that the proportion of the glass phase in the ash can be predicted from the coal mineralogy and that the utility of a given ash for processing into geopolymers or zeolites is determined by its source. 23 refs., 7 figs., 1 tab.

  16. Glass-silicon column

    DOEpatents

    Yu, Conrad M.

    2003-12-30

    A glass-silicon column that can operate in temperature variations between room temperature and about 450.degree. C. The glass-silicon column includes large area glass, such as a thin Corning 7740 boron-silicate glass bonded to a silicon wafer, with an electrode embedded in or mounted on glass of the column, and with a self alignment silicon post/glass hole structure. The glass/silicon components are bonded, for example be anodic bonding. In one embodiment, the column includes two outer layers of silicon each bonded to an inner layer of glass, with an electrode imbedded between the layers of glass, and with at least one self alignment hole and post arrangement. The electrode functions as a column heater, and one glass/silicon component is provided with a number of flow channels adjacent the bonded surfaces.

  17. Glass powder blended cement hydration modelling

    NASA Astrophysics Data System (ADS)

    Saeed, Huda

    The use of waste materials in construction is among the most attractive options to consume these materials without affecting the environment. Glass is among these types of potential waste materials. In this research, waste glass in powder form, i.e. glass powder (GP) is examined for potential use in enhancing the characteristics of concrete on the basis that it is a pozzolanic material. The experimental and the theoretical components of the work are carried out primarily to prove that glass powder belongs to the "family" of the pozzolanic materials. The chemical and physical properties of the hydrated activated glass powder and the hydrated glass powder cement on the microstructure level have been studied experimentally and theoretically. The work presented in this thesis consists of two main phases. The first phase contains experimental investigations of the reaction of glass powder with calcium hydroxide (CH) and water. In addition, it includes experiments that are aimed at determining the consumption of water and CH with time. The reactivity, degree of hydration, and nature of the pore solution of the glass powder-blended cement pastes and the effect of adding different ratios of glass powder on cement hydration is also investigated. The experiments proved that glass powder has a pozzolanic effect on cement hydration; hence it enhances the chemical and physical properties of cement paste. Based on the experimental test results, it is recommended to use a glass powder-to-cement ratio (GP/C) of 10% as an optimum ratio to achieve the best hydration and best properties of the paste. Two different chemical formulas for the produced GP C-S-H gel due to the pure GP and GP-CH pozzolanic reaction hydration are proposed. For the pure GP hydration, the produced GP C-S-H gel has a calcium-to-silica ratio (C/S) of 0.164, water-to-silica ratio (H/S) of 1.3 and sodium/silica ratio (N/S) of 0.18. However, for the GP-CH hydration, the produced GP C-S-H gel has a C/S ratio of 1

  18. How many bubbles in your glass of bubbly?

    PubMed

    Liger-Belair, Gérard

    2014-03-20

    The issue about how many carbon dioxide bubbles are likely to nucleate in a glass of champagne (or bubbly) is of concern for sommeliers, wine journalists, experienced tasters, and any open minded physical chemist wondering about complex phenomena at play in a glass of bubbly. The whole number of bubbles likely to form in a single glass is the result of the fine interplay between dissolved CO2, tiny gas pockets trapped within particles acting as bubble nucleation sites, and ascending bubble dynamics. Based on theoretical models combining ascending bubble dynamics and mass transfer equations, the falsely naı̈ve question of how many bubbles are likely to form per glass is discussed in the present work. A theoretical relationship is derived, which provides the whole number of bubbles likely to form per glass, depending on various parameters of both the wine and the glass itself.

  19. Whither Gender in Urban Health?

    PubMed Central

    Frye, Victoria; Putnam, Sara; O’Campo, Patricia

    2009-01-01

    The past decade has witnessed the rapid expansion of the field of urban health, including the establishment of an international society of urban health and annual conference, the publication of several books and the growing popularity of a peer-reviewed journal on urban health. Relatively absent is an emphasis on the role of gender in urban health, despite scholarly and theoretical work on gender and place by feminist demographers, sociologists, public health researchers and others. This essay examines the treatment of gender within urban health and, drawing on insights from the social sciences, offers suggestions as to how urban health researchers might adopt an intersectional and gendered approach that will advance our understanding of the production of urban health for women and men. PMID:18006358

  20. Experimental verification of the resistance of glass beams

    NASA Astrophysics Data System (ADS)

    Slivanský, M.

    2012-03-01

    Experimental research at the Department of Steel and Timber Structures at SUT in Bratislava focused on the verification of the behavior of modern glass structures. Four types of glass beams were tested - laminated beams made of annealed (ANG) and fully tempered glass (FTG) in interactions with or without steel elements (as reinforcement). The results of the experimental research were also compared with theoretical models using FEM calculations.

  1. Gender Development.

    ERIC Educational Resources Information Center

    Golombok, Susan; Fivush, Robyn

    In spite of the loosening ties between reproductive and social roles, the worlds of men and women and boys and girls, are clearly not the same. There is much more to being female or male than the potential to mother or father a child. Gender development does not simply depend on children's relationship with their parents: it results from a complex…

  2. Gender Development.

    ERIC Educational Resources Information Center

    Golombok, Susan; Fivush, Robyn

    In spite of the loosening ties between reproductive and social roles, the worlds of men and women and boys and girls, are clearly not the same. There is much more to being female or male than the potential to mother or father a child. Gender development does not simply depend on children's relationship with their parents: it results from a complex…

  3. Thermal rejuvenation in metallic glasses

    PubMed Central

    Saida, Junji; Yamada, Rui; Wakeda, Masato; Ogata, Shigenobu

    2017-01-01

    Abstract Structural rejuvenation in metallic glasses by a thermal process (i.e. through recovery annealing) was investigated experimentally and theoretically for various alloy compositions. An increase in the potential energy, a decrease in the density, and a change in the local structure as well as mechanical softening were observed after thermal rejuvenation. Two parameters, one related to the annealing temperature, T a/T g, and the other related to the cooling rate during the recovery annealing process, V c/V i, were proposed to evaluate the rejuvenation phenomena. A rejuvenation map was constructed using these two parameters. Since the thermal history of metallic glasses is reset above 1.2T g, accompanied by a change in the local structure, it is essential that the condition of T a/T g ≥ 1.2 is satisfied during annealing. The glassy structure transforms into a more disordered state with the decomposition of icosahedral short-range order within this temperature range. Therefore, a new glassy structure (rejuvenation) depending on the subsequent quenching rate is generated. Partial rejuvenation also occurs in a Zr55Al10Ni5Cu30 bulk metallic glass when annealing is performed at a low temperature (T a/T g ~ 1.07) followed by rapid cooling. This behavior probably originates from disordering in the weakly bonded (loosely packed) region. This study provides a novel approach to improving the mechanical properties of metallic glasses by controlling their glassy structure. PMID:28458739

  4. The Perfect Glass Paradigm: Disordered Hyperuniform Glasses Down to Absolute Zero.

    PubMed

    Zhang, G; Stillinger, F H; Torquato, S

    2016-11-28

    Rapid cooling of liquids below a certain temperature range can result in a transition to glassy states. The traditional understanding of glasses includes their thermodynamic metastability with respect to crystals. However, here we present specific examples of interactions that eliminate the possibilities of crystalline and quasicrystalline phases, while creating mechanically stable amorphous glasses down to absolute zero temperature. We show that this can be accomplished by introducing a new ideal state of matter called a "perfect glass". A perfect glass represents a soft-interaction analog of the maximally random jammed (MRJ) packings of hard particles. These latter states can be regarded as the epitome of a glass since they are out of equilibrium, maximally disordered, hyperuniform, mechanically rigid with infinite bulk and shear moduli, and can never crystallize due to configuration-space trapping. Our model perfect glass utilizes two-, three-, and four-body soft interactions while simultaneously retaining the salient attributes of the MRJ state. These models constitute a theoretical proof of concept for perfect glasses and broaden our fundamental understanding of glass physics. A novel feature of equilibrium systems of identical particles interacting with the perfect-glass potential at positive temperature is that they have a non-relativistic speed of sound that is infinite.

  5. Picture Wall (Glass Structures)

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Photo shows a subway station in Toronto, Ontario, which is entirely glass-enclosed. The all-glass structure was made possible by a unique glazing concept developed by PPG Industries, Pittsburgh, Pennsylvania, one of the largest U.S. manufacturers of flat glass. In the TVS glazing system, transparent glass "fins" replace conventional vertical support members used to provide support for wind load resistance. For stiffening, silicone sealant bonds the fins to adjacent glass panels. At its glass research center near Pittsburgh, PPG Industries uses the NASTRAN computer program to analyze the stability of enclosures made entirely of glass. The company also uses NASTRAN to simulate stresses on large containers of molten glass and to analyze stress effects of solar heating on flat glass.

  6. Theoretical Issues

    SciTech Connect

    Marc Vanderhaeghen

    2007-04-01

    The theoretical issues in the interpretation of the precision measurements of the nucleon-to-Delta transition by means of electromagnetic probes are highlighted. The results of these measurements are confronted with the state-of-the-art calculations based on chiral effective-field theories (EFT), lattice QCD, large-Nc relations, perturbative QCD, and QCD-inspired models. The link of the nucleon-to-Delta form factors to generalized parton distributions (GPDs) is also discussed.

  7. Reaction cured glass and glass coatings

    NASA Technical Reports Server (NTRS)

    Goldstein, H. E.; Leiser, D. B.; Katvala, V. W. (Inventor)

    1978-01-01

    The invention relates to reaction cured glass and glass coatings prepared by reacting a compound selected from the group consisting of silicon tetraboride, silicon hexaboride, other boron silicides, boron and mixtures with a reactive glass frit composed of a porous high silica borosilicate glass and boron oxide. The glassy composites of the present invention are useful as coatings on low density fibrous porous silica insulations used as heat shields and for articles such as reaction vessels that are subjected to high temperatures with rapid heating and cooling and that require resistance to temperature and repeated thermal shock at temperatures up to about 1482C (2700PF).

  8. Gender Writ Small: Gender Enactments and Gendered Narratives about Lab Organization and Knowledge Transmission in a Biomedical Engineering Research Setting

    NASA Astrophysics Data System (ADS)

    Malone, Kareen Ror; Nersessian, Nancy J.; Newstetter, Wendy

    This article presents qualitative data and offers some innovative theoretical approaches to frame the analysis of gender in science, technology, engineering, and mathematics (STEM) settings. It begins with a theoretical discussion of a discursive approach to gender that captures how gender is lived "on the ground." The authors argue for a less individualistic approach to gender. Data for this research project was gathered from intensive interviews with lab members and ethnographic observations in a biomedical engineering lab. Data analysis relied on a mixed methodology involving qualitative approaches and dialogues with findings from other research traditions. Three themes are highlighted: lab dynamics in relation to issues of critical mass, the division of labor, and knowledge transmission. The data illustrate how gender is created in interactions and is inflected through forms of social organization.

  9. Gender Representations in U.S. Ed.D. Dissertations: A Feminist Content Analysis

    ERIC Educational Resources Information Center

    Nelli, Debora Kay

    2014-01-01

    Educational access, achievement and opportunity for students and educators in U.S. educational institutions is influenced and often limited by gender. Although the U.S. Glass Ceiling Commission reports that the gender equity values, beliefs and commitments of institutional leaders are a key factor in reducing institutional gender inequities (U.S.…

  10. Gender Representations in U.S. Ed.D. Dissertations: A Feminist Content Analysis

    ERIC Educational Resources Information Center

    Nelli, Debora Kay

    2014-01-01

    Educational access, achievement and opportunity for students and educators in U.S. educational institutions is influenced and often limited by gender. Although the U.S. Glass Ceiling Commission reports that the gender equity values, beliefs and commitments of institutional leaders are a key factor in reducing institutional gender inequities (U.S.…

  11. Fracture Behaviour of Glass Columns Experimental Study of Axial Loaded Glass Columns

    NASA Astrophysics Data System (ADS)

    Jakab, A.; Nehme, K.; Nehme, S. G.

    2016-04-01

    Nowadays supporting structures can be transparent due to the development of glass strengthening procedures. The building glass as a versatile building material enables the efforts of the architects due to its transparency. This paper focuses on glass columns in the topic of load-bearing glasses and also on the design and load bearing capacity of fins and stability issues. Laboratory experiments were carried out at the BME, Department of Building Materials and Engineering Geology on the fracture behaviour of centrally compressed glass columns. More than 120 specimens where loaded until fracture. The load and deformations were measured. Based on the experimental results the critical force was determined and with force-deflection diagrams were illustrated the fracture and stability processes. Authors are going to compare the results of the laboratory experiments and theoretical calculations.

  12. Dynamics of Spin Glass and Spin Glass-Like Materials.

    NASA Astrophysics Data System (ADS)

    Luo, Weili

    1990-01-01

    In this dissertation extensive research on the dynamics of both metallic and insulating spin glasses is reported. Aging was found in both metallic and insulating spin glass materials. Aging manifests itself through the waiting time dependence of the relaxation rate. Relaxation at a given age can be described by two regimes: a power law for short times, and a stretched exponential (STE) for long times. In the reentrant spin glass Eu_{0.54}Sr _{0.46}S, both regimes are observed, while in the metallic spin glass only STE is present. The time decay of the TRM, _{rm TRM }(t)_{12}, at a given age, is compared with calculation by De Dominicis et al in the frame work of mean field theory. Excellent agreement between the theoretical calculation and the experimental results suggests that mean field theory can provide a qualitative description of the nature of the spin glass phase. If the measurement time is much longer than the waiting time then the relaxation rate will depend on the total age of the system, t+t_{rm w}, where t_{rm w} is the waiting time. This shows up as a deviation from STE at long times, as was observed. Aging is explained by the existence of the complex landscape of free energy. The influence of aging on dynamics is found to decrease with increasing temperature and increasing field. We interpreted this decrease as a simplification of the free energy landscape while the system gets close to the de Almeida - Thouless (AT) line. In the "frustrated ferromagnetic" phase of Eu _{0.54}Sr_ {0.46}S slow decay of TRM is found as well as aging. A new way to determine the phase diagram from the dynamic point of view is presented.

  13. 6. Looking glass aircraft in the project looking glass historic ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. Looking glass aircraft in the project looking glass historic district. View to north. - Offutt Air Force Base, Looking Glass Airborne Command Post, Looking Glass Avenue between Comstat Drive & Nightwatch Avenue, Offutt Air Force Base, Bellevue, Sarpy County, NE

  14. Theoretical geology

    NASA Astrophysics Data System (ADS)

    Mikeš, Daniel

    2010-05-01

    Theoretical geology Present day geology is mostly empirical of nature. I claim that geology is by nature complex and that the empirical approach is bound to fail. Let's consider the input to be the set of ambient conditions and the output to be the sedimentary rock record. I claim that the output can only be deduced from the input if the relation from input to output be known. The fundamental question is therefore the following: Can one predict the output from the input or can one predict the behaviour of a sedimentary system? If one can, than the empirical/deductive method has changes, if one can't than that method is bound to fail. The fundamental problem to solve is therefore the following: How to predict the behaviour of a sedimentary system? It is interesting to observe that this question is never asked and many a study is conducted by the empirical/deductive method; it seems that the empirical method has been accepted as being appropriate without question. It is, however, easy to argument that a sedimentary system is by nature complex and that several input parameters vary at the same time and that they can create similar output in the rock record. It follows trivially from these first principles that in such a case the deductive solution cannot be unique. At the same time several geological methods depart precisely from the assumption, that one particular variable is the dictator/driver and that the others are constant, even though the data do not support such an assumption. The method of "sequence stratigraphy" is a typical example of such a dogma. It can be easily argued that all the interpretation resulting from a method that is built on uncertain or wrong assumptions is erroneous. Still, this method has survived for many years, nonwithstanding all the critics it has received. This is just one example of the present day geological world and is not unique. Even the alternative methods criticising sequence stratigraphy actually depart from the same

  15. Oxynitride glass fibers

    NASA Technical Reports Server (NTRS)

    Patel, Parimal J.; Messier, Donald R.; Rich, R. E.

    1991-01-01

    Research at the Army Materials Technology Laboratory (AMTL) and elsewhere has shown that many glass properties including elastic modulus, hardness, and corrosion resistance are improved markedly by the substitution of nitrogen for oxygen in the glass structure. Oxynitride glasses, therefore, offer exciting opportunities for making high modulus, high strength fibers. Processes for making oxynitride glasses and fibers of glass compositions similar to commercial oxide glasses, but with considerable enhanced properties, are discussed. We have made glasses with elastic moduli as high as 140 GPa and fibers with moduli of 120 GPa and tensile strengths up to 2900 MPa. AMTL holds a U.S. patent on oxynitride glass fibers, and this presentation discusses a unique process for drawing small diameter oxynitride glass fibers at high drawing rates. Fibers are drawn through a nozzle from molten glass in a molybdenum crucible at 1550 C. The crucible is situated in a furnace chamber in flowing nitrogen, and the fiber is wound in air outside of the chamber, making the process straightforward and commercially feasible. Strengths were considerably improved by improving glass quality to minimize internal defects. Though the fiber strengths were comparable with oxide fibers, work is currently in progress to further improve the elastic modulus and strength of fibers. The high elastic modulus of oxynitride glasses indicate their potential for making fibers with tensile strengths surpassing any oxide glass fibers, and we hope to realize that potential in the near future.

  16. Theoretical Basis for the Design of a DWPF Evacuated Canister

    SciTech Connect

    Routt, K.R.

    2001-09-17

    This report provides the theoretical bases for use of an evacuated canister for draining a glass melter. Design recommendations are also presented to ensure satisfactory performance in future tests of the concept.

  17. Failure in glass

    NASA Technical Reports Server (NTRS)

    Keeton, S. C.

    1972-01-01

    Review of state of the art concerning glass failure mechanisms and fatigue theories discusses brittle fracture in glass, fatigue mechanisms, fatigue behavior, environmental effects on failure rate, and aging.

  18. Glass tube splitting tool

    NASA Technical Reports Server (NTRS)

    Klein, J. A.; Murray, C. D.; Stein, J. A.

    1971-01-01

    Tool accurately splits glass tubing so cuts are aligned 180 deg apart and reassembled tube forms low pressure, gastight enclosure. Device should interest industries using cylindrical closed glass containers.

  19. Theoretical Mathematics

    NASA Astrophysics Data System (ADS)

    Stöltzner, Michael

    Answering to the double-faced influence of string theory on mathematical practice and rigour, the mathematical physicists Arthur Jaffe and Frank Quinn have contemplated the idea that there exists a `theoretical' mathematics (alongside `theoretical' physics) whose basic structures and results still require independent corroboration by mathematical proof. In this paper, I shall take the Jaffe-Quinn debate mainly as a problem of mathematical ontology and analyse it against the backdrop of two philosophical views that are appreciative towards informal mathematical development and conjectural results: Lakatos's methodology of proofs and refutations and John von Neumann's opportunistic reading of Hilbert's axiomatic method. The comparison of both approaches shows that mitigating Lakatos's falsificationism makes his insights about mathematical quasi-ontology more relevant to 20th century mathematics in which new structures are introduced by axiomatisation and not necessarily motivated by informal ancestors. The final section discusses the consequences of string theorists' claim to finality for the theory's mathematical make-up. I argue that ontological reductionism as advocated by particle physicists and the quest for mathematically deeper axioms do not necessarily lead to identical results.

  20. Staging Gender: The Articulation of Tacit Gender Dimensions in Drama Classes in a Swedish Context

    ERIC Educational Resources Information Center

    Lund, Anna

    2013-01-01

    This article engages with gender, performance and embodiment in drama classes in a Swedish context. It presents a case study of how instructors at an academy of dramatic arts integrate theoretical knowledge on gender into their students' creative and pedagogical practice, as well as an analysis of why this approach works. Visualisation of how the…

  1. Basotho Teachers' Constructions of Gender: Implications on Gender Equality in the Schools

    ERIC Educational Resources Information Center

    Morojele, P. J.

    2012-01-01

    This paper gives prominence to rural teachers' own accounts of gender in three co-educational primary schools in Lesotho. The paper employs the social constructionist paradigm as its theoretical framework. Drawing from ethnographic data (observations and informal discussions), it discusses factors that inform teachers' constructions of gender and…

  2. Basotho Teachers' Constructions of Gender: Implications on Gender Equality in the Schools

    ERIC Educational Resources Information Center

    Morojele, P. J.

    2012-01-01

    This paper gives prominence to rural teachers' own accounts of gender in three co-educational primary schools in Lesotho. The paper employs the social constructionist paradigm as its theoretical framework. Drawing from ethnographic data (observations and informal discussions), it discusses factors that inform teachers' constructions of gender and…

  3. Staging Gender: The Articulation of Tacit Gender Dimensions in Drama Classes in a Swedish Context

    ERIC Educational Resources Information Center

    Lund, Anna

    2013-01-01

    This article engages with gender, performance and embodiment in drama classes in a Swedish context. It presents a case study of how instructors at an academy of dramatic arts integrate theoretical knowledge on gender into their students' creative and pedagogical practice, as well as an analysis of why this approach works. Visualisation of how the…

  4. Weakly supervised glasses removal

    NASA Astrophysics Data System (ADS)

    Wang, Zhicheng; Zhou, Yisu; Wen, Lijie

    2015-03-01

    Glasses removal is an important task on face recognition, in this paper, we provide a weakly supervised method to remove eyeglasses from an input face image automatically. We choose sparse coding as face reconstruction method, and optical flow to find exact shape of glasses. We combine the two processes iteratively to remove glasses more accurately. The experimental results reveal that our method works much better than these algorithms alone, and it can remove various glasses to obtain natural looking glassless facial images.

  5. [Gender mainstreaming and nursing].

    PubMed

    Wang, Hsiu-Hung

    2011-12-01

    Gender mainstreaming is one of the most important strategies in promoting global gender equality. The Taiwan government launched policies on gender mainstreaming and gender impact assessment in 2007 in response to strong public and academic advocacy work. With rising awareness of gender issues, nursing professionals in Taiwan should keep pace with global trends and become actively involved in advancing gender-mainstreaming policies. This article shows that nursing professionals should prepare themselves by cultivating gender competence, understanding gender-related regulations, recognizing the importance of gender impact assessment implementation, integrating gender issues into nursing education, conducting gender-related research and participating in decision-making processes that promote gender mainstreaming. Nursing professionals should enhance their knowledge and understanding of gender mainstreaming-related issues and get involved in the gender-related decision-making process in order to enhance gender awareness and women's health and further the professional development of nurses.

  6. Technique for Machining Glass

    NASA Technical Reports Server (NTRS)

    Rice, S. H.

    1982-01-01

    Process for machining glass with conventional carbide tools requires a small quantity of a lubricant for aluminum applied to area of glass to be machined. A carbide tool is then placed against workpiece with light pressure. Tool is raised periodically to clear work of glass dust and particles. Additional lubricant is applied as it is displaced.

  7. Glass in Class

    ERIC Educational Resources Information Center

    Greaves, Neville

    2005-01-01

    Glass is reviewed from fabrication to application, laying emphasis on the wide-ranging physics involved. This begins with liquids and solids and the way in which glasses are defined and can be demonstrated in the classroom. At the atomic level the regular structure of crystals and their irregular counterparts in glasses are explained through…

  8. Glass in Class

    ERIC Educational Resources Information Center

    Greaves, Neville

    2005-01-01

    Glass is reviewed from fabrication to application, laying emphasis on the wide-ranging physics involved. This begins with liquids and solids and the way in which glasses are defined and can be demonstrated in the classroom. At the atomic level the regular structure of crystals and their irregular counterparts in glasses are explained through…

  9. Technique for Machining Glass

    NASA Technical Reports Server (NTRS)

    Rice, S. H.

    1982-01-01

    Process for machining glass with conventional carbide tools requires a small quantity of a lubricant for aluminum applied to area of glass to be machined. A carbide tool is then placed against workpiece with light pressure. Tool is raised periodically to clear work of glass dust and particles. Additional lubricant is applied as it is displaced.

  10. Infrared Transparent Selenide Glasses.

    DTIC Science & Technology

    1997-03-14

    crystalline halides, silica and fluoride glasses, and chalcogenide glasses. Crystalline halides undergo plastic deformation and are hygroscopic...mainly for applications operating at wavelengths less than 3 microns. Silicate and fluoride glasses have been developed as optical fiber amplifiers...activity. Preferred rare earths includes praseodymium, neodymium, erbium, cerium , dysprosium, holmium, thulium, terbium, ytterbium or mixtures of

  11. Apollo 17 ropy glasses

    NASA Technical Reports Server (NTRS)

    Fruland, R. M.; Morris, R. V.; Mckay, D. S.; Clanton, U. S.

    1977-01-01

    Ropy glasses are a major soil component in the Apollo 17 gray soils 74240 and 74260. These particles form a distinct morphological type characterized by a wide range of dynamic shapes with a diagnostic sorted and welded fine-grained debris coating. Apollo 17 ropy glasses show abundant evidence for shock. Shocked lithic and mineral inclusions, lack of any igneous textures, and lechatelierite, all indicate an impact origin. A striking similarity is observed between the lunar ropy glasses and the glass impact bombs (Flaedle) of the Ries Crater in Germany. A highland basaltic composition was observed for the Apollo 17 ropy glasses in contrast to the KREEP composition of ropy glasses from the Apollo 12 and Apollo 14 landing sites. Other workers have presented convincing evidence that ejecta from Tycho reached the Taurus-Littrow Valley, and these ropy glasses may represent Tycho ejecta. However, the close stratigraphic association of the ropy glasses with the greater than 3.5 b.y. old orange glass suggests the ropy glasses may be too old to be Tycho ejecta, which should be only about 100 m.y. old. If this is the case, the ropy glasses represent impact glasses from a very old impact in an unknown highlands source area.

  12. The Perfect Glass Paradigm: Disordered Hyperuniform Glasses Down to Absolute Zero

    NASA Astrophysics Data System (ADS)

    Zhang, G.; Stillinger, F. H.; Torquato, S.

    2016-11-01

    Rapid cooling of liquids below a certain temperature range can result in a transition to glassy states. The traditional understanding of glasses includes their thermodynamic metastability with respect to crystals. However, here we present specific examples of interactions that eliminate the possibilities of crystalline and quasicrystalline phases, while creating mechanically stable amorphous glasses down to absolute zero temperature. We show that this can be accomplished by introducing a new ideal state of matter called a “perfect glass”. A perfect glass represents a soft-interaction analog of the maximally random jammed (MRJ) packings of hard particles. These latter states can be regarded as the epitome of a glass since they are out of equilibrium, maximally disordered, hyperuniform, mechanically rigid with infinite bulk and shear moduli, and can never crystallize due to configuration-space trapping. Our model perfect glass utilizes two-, three-, and four-body soft interactions while simultaneously retaining the salient attributes of the MRJ state. These models constitute a theoretical proof of concept for perfect glasses and broaden our fundamental understanding of glass physics. A novel feature of equilibrium systems of identical particles interacting with the perfect-glass potential at positive temperature is that they have a non-relativistic speed of sound that is infinite.

  13. The Perfect Glass Paradigm: Disordered Hyperuniform Glasses Down to Absolute Zero

    PubMed Central

    Zhang, G.; Stillinger, F. H.; Torquato, S.

    2016-01-01

    Rapid cooling of liquids below a certain temperature range can result in a transition to glassy states. The traditional understanding of glasses includes their thermodynamic metastability with respect to crystals. However, here we present specific examples of interactions that eliminate the possibilities of crystalline and quasicrystalline phases, while creating mechanically stable amorphous glasses down to absolute zero temperature. We show that this can be accomplished by introducing a new ideal state of matter called a “perfect glass”. A perfect glass represents a soft-interaction analog of the maximally random jammed (MRJ) packings of hard particles. These latter states can be regarded as the epitome of a glass since they are out of equilibrium, maximally disordered, hyperuniform, mechanically rigid with infinite bulk and shear moduli, and can never crystallize due to configuration-space trapping. Our model perfect glass utilizes two-, three-, and four-body soft interactions while simultaneously retaining the salient attributes of the MRJ state. These models constitute a theoretical proof of concept for perfect glasses and broaden our fundamental understanding of glass physics. A novel feature of equilibrium systems of identical particles interacting with the perfect-glass potential at positive temperature is that they have a non-relativistic speed of sound that is infinite. PMID:27892452

  14. Is `gender-sensitive education' a useful concept for educational policy?

    NASA Astrophysics Data System (ADS)

    Forde, Christine

    2014-06-01

    This article responds to Astrid Sinnes and Marianne Løken's article `Gendered education in a gendered world: Looking beyond cosmetic solutions to the gender gap in science' by exploring the idea of `gender-sensitive' education and its usefulness in educational policy. It draws on theoretical discussions of the concept of gender and of difference to consider ways in which `gender-sensitive' education might serve the task of promoting equality and justice.

  15. RELATIVISTIC HEAVY ION PHYSICS: A THEORETICAL OVERVIEW.

    SciTech Connect

    KHARZEEV,D.

    2004-03-28

    This is a mini-review of recent theoretical work in the field of relativistic heavy ion physics. The following topics are discussed initial conditions and the Color Glass Condensate; approach to thermalization and the hydrodynamic evolution; hard probes and the properties of the Quark-Gluon Plasma. Some of the unsolved problems and potentially promising directions for future research are listed as well.

  16. Gender Differences in Depressive Symptoms during Adolescence: The Contributions of Weight-Related Concerns and Behaviors

    ERIC Educational Resources Information Center

    Vaughan, Christine A.; Halpern, Carolyn T.

    2010-01-01

    A theoretical model of gender differences in depressive symptoms during adolescence was evaluated using data from Waves I and II of the National Longitudinal Study of Adolescent Health. The theoretical model under examination was primarily informed by the gender-additive model of gender differences in depressive symptoms during adolescence…

  17. Oxynitride glass production procedure

    DOEpatents

    Weidner, Jerry R.; Schuetz, Stanley T.; O'Brien, Michael H.

    1991-01-01

    The invention is a process for the preparation of high quality oxynitride glasses without resorting to high pressures. Nitrogen-containing compounds such as Si.sub.3 N.sub.4 are first encapsulated in a low melting temperature glass. Particles of the encapsulated nitrogen-containing compound are mixed with other oxide glass-formers and melted in an atmosphere of flowing nitrogen and in the presence of buffering gas to form the oxynitride glass. Glasses containing up to 15 at % nitrogen have been prepared by this method.

  18. Radiation coloration resistant glass

    DOEpatents

    Tomozawa, M.; Watson, E.B.; Acocella, J.

    1986-11-04

    A radiation coloration resistant glass is disclosed which is used in a radiation environment sufficient to cause coloration in most forms of glass. The coloration resistant glass includes higher proportions by weight of water and has been found to be extremely resistant to color change when exposed to such radiation levels. The coloration resistant glass is free of cerium oxide and has more than about 0.5% by weight water content. Even when exposed to gamma radiation of more than 10[sup 7] rad, the coloration resistant glass does not lose transparency. 3 figs.

  19. Radiation coloration resistant glass

    DOEpatents

    Tomozawa, Minoru; Watson, E. Bruce; Acocella, John

    1986-01-01

    A radiation coloration resistant glass is disclosed which is used in a radiation environment sufficient to cause coloration in most forms of glass. The coloration resistant glass includes higher proportions by weight of water and has been found to be extremely resistant to color change when exposed to such radiation levels. The coloration resistant glass is free of cerium oxide and has more than about 0.5% by weight water content. Even when exposed to gamma radiation of more than 10.sup.7 rad, the coloration resistant glass does not lose transparency.

  20. Production of Bulk and Fiber Glass in Space

    NASA Technical Reports Server (NTRS)

    Tucker, Dennis S.; Whitaker, Ann F. (Technical Monitor)

    2001-01-01

    The production of bulk glass and fiber glass in space and on the moon and Mars should lead to superior products. Specifically glass plates for windows and optical elements could be produced with theoretical strengths by production in vacuum. Water vapor is known to decrease glass strength by up to two orders of magnitude from theoretical. A low gravity glass plate apparatus prototype has been designed and built which uses centrifugal force to shape the glass and solar energy to melt the glass. Glass fiber could be produced on the moon or Mars from in-situ materials using standard technologies. This material could then be used as reinforcement in composite materials in construction of bases. Also, it has been shown that processing in reduced gravity suppresses crystallization in certain heavy metal fluoride glasses. It is proposed to reprocess optical fiber preforms on the space station and then pull these into optical fiber. It is estimated that the attenuation coefficient should be reduced by two orders of magnitude.

  1. Developing photorefractive glass composites

    NASA Astrophysics Data System (ADS)

    Duignan, Jason P.; Taylor, Lesley L.; Cook, Gary

    2002-01-01

    The production of a transparent photorefractive glass composite would offer a useful alternative to bulk crystal materials. We aim to produce such a material by incorporating single domain photorefractive Fe:LiNbO3 particles into a refractive index matched glass host. This glass host is also required to be chemically compatible with the photorefractive material. This compatibility will ensure that the Fe:LiNbO3 particles added to the host glass will remain in the intended crystalline phase and not simply dissolve in the glass. Due to the high refractive index of the Fe:LiNbO3 (no equals 2.35 532 nm), producing a chemically compatible and refractive index matched glass host is technically challenging. By examining common Tellurite, Bismuthate, and Gallate glasses as a starting point and then developing new and hybrid glasses, we have succeeded in producing a chemically compatible glass host and also a refractive index matched glass host. We have produced preliminary glass composite samples which contain a large amount of Fe:LiNbO3. We are currently able to retain nearly 90% of the incorporated Fe:LiNbO3 in the correct crystalline phase, a substantial improvement over previous work conducted in this area in recent years. In this paper we present our progress and findings in this area.

  2. Application of the hydration thermodynamic model for glass durability under saturated tuff repository conditions

    SciTech Connect

    Ramsey, W.G.; Jantzen, C.M.

    1990-12-31

    The effects of tuff repository groundwater on glass dissolution and surface layer formation was examined utilizing the hydration thermodynamic model. A 28 day MCC-1 monolithic durability test was performed on the following glasses: SiO{sub 2}, obsidian, basalt, medieval window glasses, frit glass, and simulated nuclear waste glass. Silica dissolution was compared with the pH corrected free energy of hydration and shown to have the theoretical slope, ln(1/2.303RT), in agreement with MCC-1 tests using deionized water. X-ray diffraction and scanning electron microscopy identified clays of the saponite family and carbonates, on the glass surfaces leached in tuff groundwater. 31 refs.

  3. Acoustics of glass harmonicas

    NASA Astrophysics Data System (ADS)

    Rossing, Thomas D.

    2004-05-01

    Glass musical instruments are probably as old as glassmaking. At least as early as the 17th century it was discovered that wine glasses, when rubbed with a wet finger, produced a musical tone. A collection of glasses played in this manner is called a glass harp. Another type of glass harmonica, called the armonica by its inventor Benjamin Franklin, employs glass bowls or cups turned by a horizontal axle, so the performer need only touch the rim of the bowls as they rotate to set them into vibration. We discuss the modes of vibration of both types of glass harmonica, and describe the different sounds that are emitted by rubbing, tapping, or bowing them. Rubbing with a wet finger tends to excite only the (2,0) mode and its harmonics through a ``stick-slip'' process, while tapping excites the other modes as well.

  4. Optical Basicity and Nepheline Crystallization in High Alumina Glasses

    SciTech Connect

    Rodriguez, Carmen P.; McCloy, John S.; Schweiger, M. J.; Crum, Jarrod V.; Winschell, Abigail E.

    2011-02-25

    The purpose of this study was to find compositions that increase waste loading of high-alumina wastes beyond what is currently acceptable while avoiding crystallization of nepheline (NaAlSiO4) on slow cooling. Nepheline crystallization has been shown to have a large impact on the chemical durability of high-level waste glasses. It was hypothesized that there would be some composition regions where high-alumina would not result in nepheline crystal production, compositions not currently allowed by the nepheline discriminator. Optical basicity (OB) and the nepheline discriminator (ND) are two ways of describing a given complex glass composition. This report presents the theoretical and experimental basis for these models. They are being studied together in a quadrant system as metrics to explore nepheline crystallization and chemical durability as a function of waste glass composition. These metrics were calculated for glasses with existing data and also for theoretical glasses to explore nepheline formation in Quadrant IV (passes OB metric but fails ND metric), where glasses are presumed to have good chemical durability. Several of these compositions were chosen, and glasses were made to fill poorly represented regions in Quadrant IV. To evaluate nepheline formation and chemical durability of these glasses, quantitative X-ray diffraction (XRD) analysis and the Product Consistency Test were conducted. A large amount of quantitative XRD data is collected here, both from new glasses and from glasses of previous studies that had not previously performed quantitative XRD on the phase assemblage. Appendix A critically discusses a large dataset to be considered for future quantitative studies on nepheline formation in glass. Appendix B provides a theoretical justification for choice of the oxide coefficients used to compute the OB criterion for nepheline formation.

  5. Theoretical geodesy

    NASA Astrophysics Data System (ADS)

    Borkowski, Andrzej; Kosek, Wiesław

    2015-12-01

    The paper presents a summary of research activities concerning theoretical geodesy performed in Poland in the period of 2011-2014. It contains the results of research on new methods of the parameter estimation, a study on robustness properties of the M-estimation, control network and deformation analysis, and geodetic time series analysis. The main achievements in the geodetic parameter estimation involve a new model of the M-estimation with probabilistic models of geodetic observations, a new Shift-Msplit estimation, which allows to estimate a vector of parameter differences and the Shift-Msplit(+) that is a generalisation of Shift-Msplit estimation if the design matrix A of a functional model has not a full column rank. The new algorithms of the coordinates conversion between the Cartesian and geodetic coordinates, both on the rotational and triaxial ellipsoid can be mentioned as a highlights of the research of the last four years. New parameter estimation models developed have been adopted and successfully applied to the control network and deformation analysis. New algorithms based on the wavelet, Fourier and Hilbert transforms were applied to find time-frequency characteristics of geodetic and geophysical time series as well as time-frequency relations between them. Statistical properties of these time series are also presented using different statistical tests as well as 2nd, 3rd and 4th moments about the mean. The new forecasts methods are presented which enable prediction of the considered time series in different frequency bands.

  6. Is "Gender-Sensitive Education" a Useful Concept for Educational Policy?

    ERIC Educational Resources Information Center

    Forde, Christine

    2014-01-01

    This article responds to Astrid Sinnes and Marianne Løken's article "Gendered education in a gendered world: Looking beyond cosmetic solutions to the gender gap in science" by exploring the idea of "gender-sensitive" education and its usefulness in educational policy. It draws on theoretical discussions of the concept of…

  7. Re/Theorising Gender: Female Masculinity and Male Femininity in the Classroom?

    ERIC Educational Resources Information Center

    Francis, Becky

    2010-01-01

    Recent gender theorising has been enlivened by post-structuralist accounts of gender as "disembodied"; the reading of gender performances as distinct from sexed bodies. However, there has been little application of such theoretical positions to empirical analysis in gender and education. This article employs two such positions--that of…

  8. Is "Gender-Sensitive Education" a Useful Concept for Educational Policy?

    ERIC Educational Resources Information Center

    Forde, Christine

    2014-01-01

    This article responds to Astrid Sinnes and Marianne Løken's article "Gendered education in a gendered world: Looking beyond cosmetic solutions to the gender gap in science" by exploring the idea of "gender-sensitive" education and its usefulness in educational policy. It draws on theoretical discussions of the concept of…

  9. Re/Theorising Gender: Female Masculinity and Male Femininity in the Classroom?

    ERIC Educational Resources Information Center

    Francis, Becky

    2010-01-01

    Recent gender theorising has been enlivened by post-structuralist accounts of gender as "disembodied"; the reading of gender performances as distinct from sexed bodies. However, there has been little application of such theoretical positions to empirical analysis in gender and education. This article employs two such positions--that of…

  10. Glass and glass-ceramic photonic systems

    NASA Astrophysics Data System (ADS)

    Zur, Lidia; Thi Ngoc Tran, Lam; Meneghetti, Marcello; Varas, Stefano; Armellini, Cristina; Ristic, Davor; Chiasera, Alessandro; Scotognella, Francesco; Pelli, Stefano; Nunzi Conti, Gualtiero; Boulard, Brigitte; Zonta, Daniele; Dorosz, Dominik; Lukowiak, Anna; Righini, Giancarlo C.; Ramponi, Roberta; Ferrari, Maurizio

    2017-02-01

    The development of optically confined structure is a major topic in both basic and applied physics not solely ICT oriented but also concerning lighting, laser, sensing, energy, environment, biological and medical sciences, and quantum optics. Glasses and glass-ceramics activated by rare earth ions are the bricks of such structures. Glass-ceramics are nanocomposite systems that exhibit specific morphologic, structural and spectroscopic properties allowing developing new physical concepts, for instance the mechanism related to the transparency, as well as novel photonic devices based on the enhancement of the luminescence. The dependence of the final product on the specific parent glass and on the fabrication protocol still remain an important task of the research in material science. Looking to application, the enhanced spectroscopic properties typical of glass ceramic in respect to those of the amorphous structures constitute an important point for the development of integrated optics devices, including optical amplifiers, monolithic waveguide laser, novel sensors, coating of spherical microresonators, and up and down converters. This paper presents some results obtained by our consortium regarding glass-based photonics systems. We will comment the energy transfer mechanism in transparent glass ceramics taking as examples the up and down conversion systems and the role of SnO2 nanocrystals as sensitizers. Coating of spherical resonators by glass ceramics, 1D-Photonic Crystals for luminescence enhancement, laser action and disordered 1-D photonic structures will be also discussed. Finally, RF-Sputtered rare earth doped P2O5- SiO2-Al2O3-Na2O-Er2O3 planar waveguides, will be presented.

  11. Ideology and gender: observers' system justification and targets' gender as interactive predictors of citizenship expectations.

    PubMed

    Chiaburu, Dan S; Harris, T Brad; Smith, Troy A

    2014-01-01

    We integrate system justification and social role theory to explain how observers' system justification and target employees' gender interact to predict observers' expectations of targets' sportsmanship citizenship behaviors. In contrast with social role theory predictions, observers did not expect greater levels of sportsmanship from women compared to men. Yet observers expected more sportsmanship from women (a) when observers were ideologically motivated by gender-specific beliefs (gender-specific system justification; Study 1) and (b) when system justification was cued experimentally (Study 2). A heretofore-unexamined aspect, observers' ideology, modifies their expectations of sportsmanship citizenship across target genders. This has implications for system justification, social role, and organizational citizenship theoretical perspectives.

  12. Gender compatibility, math-gender stereotypes, and self-concepts in math and physics

    NASA Astrophysics Data System (ADS)

    Koul, Ravinder; Lerdpornkulrat, Thanita; Poondej, Chanut

    2016-12-01

    [This paper is part of the Focused Collection on Gender in Physics.] Positive self-assessment of ability in the quantitative domains is considered critical for student participation in science, technology, engineering, and mathematics field studies. The present study investigated associations of gender compatibility (gender typicality and contentedness) and math-gender stereotypes with self-concepts in math and physics. Statistical analysis of survey data was based on a sample of 170 male and female high school science students matched on propensity scores based on age and past GPA scores in math. Results of MANCOVA analyses indicated that the combination of high personal gender compatibility with low endorsement of math-gender stereotypes was associated with low gender differentials in math and physics self-concepts whereas the combination of high personal gender compatibility with high endorsement of math-gender stereotypes was associated with high gender differentials in math and physics self-concepts. These results contribute to the recent theoretical and empirical work on antecedents to the math and physics identities critical to achieving gender equity in STEM fields.

  13. Quantifying the cleanliness of glass capillaries.

    PubMed

    Bowman, C L

    1998-01-01

    I used capillary rise methods to investigate the lumenal surface properties of quartz (fused silica, Amersil T-08), borosilicate (Corning 7800), and high-lead glass (Corning 0010) capillaries commonly used to make patch pipets. I calculated the capillary rise and contact angle for water and methanol from weight measurements. The capillary rise was compared with the theoretical maximum value calculated by assuming each fluid perfectly wetted the lumenal surface of the glass (i.e., zero contact angle, which reflects the absence of surface contamination). For borosilicate, high-lead, and quartz capillaries, the rise for water was substantially less than the theoretical maximum rise. Exposure of the borosilicate, lead, and quartz capillaries to several cleaning methods resulted in substantially better--but not perfect--agreement between the theoretical maximum rise and calculated capillary rise. By contrast, the capillary rise for methanol was almost identical in untreated and cleaned capillaries, but less than its theoretical maximum rise. The residual discrepancy between the observed and theoretical rise for water could not be improved on by trying a variety of cleaning procedures, but some cleaning methods were superior to others. The water solubility of the surface contaminants, deduced from the effectiveness of repeated rinsing, was different for each of the three types of capillaries examined: Corning 7800 > quartz > Corning 0010. A surface film was also detected in quatz tubing with an internal filament. I conclude that these borosilicate, quartz, and high-lead glass capillaries have a film on the lumenal surface, which can be removed using appropriate cleaning methods. The surface contaminants may be unique to each type of capillary and may also be hydrophobic. Two simple methods are presented to quantitate the cleanliness of glass capillary tubing commonly used to make pipets for studies of biological membranes. It is not known if the surface film is of

  14. Metal Halide Optical Glasses.

    DTIC Science & Technology

    1988-01-01

    HEAVY METAL FLUORIDE GLASSES C. T. Moynihan, R. Mossadegh and S. N. Crichton Materials Engineering Department, Rensselaer Polytechnic Institute Troy...and Tesar, A. A., J. Am. Ceram. Soc., 67, p. C-164 (1984). 11. Crichton , S. N., Mossadegh, R., Schroeder, J., and Moynihan, C. T., unpublished data. 12...FLUORIDE GLASSES C. T. Moynihan, S. M. Opalka, R. Mossadegh, S. N. Crichton and A. J. Bruce Center for Glass Science and Technology Materials Engineering

  15. Diamond turning of glass

    SciTech Connect

    Blackley, W.S.; Scattergood, R.O.

    1988-12-01

    A new research initiative will be undertaken to investigate the critical cutting depth concepts for single point diamond turning of brittle, amorphous materials. Inorganic glasses and a brittle, thermoset polymer (organic glass) are the principal candidate materials. Interrupted cutting tests similar to those done in earlier research are Ge and Si crystals will be made to obtain critical depth values as a function of machining parameters. The results will provide systematic data with which to assess machining performance on glasses and amorphous materials

  16. Reversing Glass Wettability

    NASA Technical Reports Server (NTRS)

    Frazier, D. O.; Smith, J. E., Jr.; Kaukler, W. F.

    1985-01-01

    Treatment reverses wettability of glassware: Liquids that normally wet glass no longer do, and those that do not wet glass are made to do so. Useful in research on container effects in nucleation and growth of secondary phase from solution. Treatment consists of spreading 3 percent (by weight) solution of silicone oil in hexane isomers over glass, drying in air, and curing at 300 degrees C in vacuum for one hour.

  17. Fibre glass induced synovitis.

    PubMed Central

    Cleland, L G; Vernon-Roberts, B; Smith, K

    1984-01-01

    Chronic synovitis developed in the dorsal extensor sheath of the hand of a 25-year-old manufacturer of fibre glass reinforced boats and surfboards . Particles found in synovial fluid aspirates were similar in morphology and elemental content to unused fibre glass and particles found in dust from the workshop floor. It was concluded that hard disc grinding required during manufacture resulted in percutaneous implantation of small glass particles, leading to chronic synovitis and effusion. Images PMID:6742919

  18. A Modest Manifesto for Shattering the Glass Ceiling.

    ERIC Educational Resources Information Center

    Meyerson, Debra E.; Fletcher, Joyce K.

    2000-01-01

    Approaches to the glass ceiling--encouraging women to adopt "masculine" attributes, accommodating women's unique needs, or celebrating women's differences--have shortcomings. A fourth approach links equity and effectiveness. "Small wins" recognizes that gender inequity is rooted in cultural patterns and uses small initiatives…

  19. A Modest Manifesto for Shattering the Glass Ceiling.

    ERIC Educational Resources Information Center

    Meyerson, Debra E.; Fletcher, Joyce K.

    2000-01-01

    Approaches to the glass ceiling--encouraging women to adopt "masculine" attributes, accommodating women's unique needs, or celebrating women's differences--have shortcomings. A fourth approach links equity and effectiveness. "Small wins" recognizes that gender inequity is rooted in cultural patterns and uses small initiatives…

  20. Gender and medical careers.

    PubMed

    Riska, Elianne

    2011-03-01

    The concerns about physicians' career advancement tend to be raised in gender terms, because women presently constitute close to and will soon form a majority of the medical students in most western societies. The question is to what extent female and male medical students and residents today make similar or different career and lifestyle choices? Two major mechanisms have been referred to as the reason for gender differences in career paths for physicians. The major theoretical framework tends to be the socialization or sex-role theory and later versions of this explanatory framework. The other mechanism referred to is structural and points to the barriers or the concrete support that women and men experience in making their career decisions. Studies of medical students in the UK and US have shown that women students expected family demands to hamper career plans, while male students were less influenced by family concerns. The importance of role models and mentors in setting the career goals of medical students and residents has recently confirmed early studies of the topic. A number of studies have documented that early negative experiences or lack of encouragement in medical school deter women from choosing surgery as a career. Recent studies suggest that lifestyle choices rather than merely career advancement influence both female and male surgeons' career plans.

  1. Apollo 15 green glasses.

    NASA Technical Reports Server (NTRS)

    Ridley, W. I.; Reid, A. M.; Warner, J. L.; Brown, R. W.

    1973-01-01

    The samples analyzed include 28 spheres, portions of spheres, and angular fragments from soil 15101. Emerald green glasses from other soils are identical to those from 15101. The composition of the green glass is unlike that of any other major lunar glass group. The Fe content is comparable to that in mare basalts, but Ti is much lower. The Mg content is much higher than in most lunar materials analyzed to date, and the Cr content is also high. The low Al content is comparable to that of mare basalt glasses.

  2. Chalcogenide glass microsphere laser.

    PubMed

    Elliott, Gregor R; Murugan, G Senthil; Wilkinson, James S; Zervas, Michalis N; Hewak, Daniel W

    2010-12-06

    Laser action has been demonstrated in chalcogenide glass microsphere. A sub millimeter neodymium-doped gallium lanthanum sulphide glass sphere was pumped at 808 nm with a laser diode and single and multimode laser action demonstrated at wavelengths between 1075 and 1086 nm. The gallium lanthanum sulphide family of glass offer higher thermal stability compared to other chalcogenide glasses, and this, along with an optimized Q-factor for the microcavity allowed laser action to be achieved. When varying the pump power, changes in the output spectrum suggest nonlinear and/or thermal effects have a strong effect on laser action.

  3. Drugstore Reading Glasses

    NASA Astrophysics Data System (ADS)

    Erlichson, Herman

    2006-03-01

    The occasion for this paper was my reading of a paper in the February 2005 issue of TPT. As one gets older the near point of the eye begins to recede.2 This is called presbyopia.3 An alternative to purchasing glasses from an optometrist is to purchase an inexpensive pair of reading glasses in a pharmacy. The pharmacy has these glasses ordered by diopters corresponding to the strength of the lens needed for a particular presbyopic eye. The glasses are, of course, not available for myopic eyes.

  4. Photoprotection: clothing and glass.

    PubMed

    Almutawa, Fahad; Buabbas, Hanan

    2014-07-01

    Ultraviolet (UV) radiation (UVR) has well-known adverse effects on the skin and eyes. Little attention is given to physical means of photoprotection, namely glass, window films, sunglasses, and clothing. In general, all types of glass block UV-B. For UV-A, the degree of transmission depends on the type, thickness, and color of the glass. Adding window films to glass can greatly decrease the transmission of UV-A. Factors that can affect the transmission of UVR through cloth include tightness of weave, thickness, weight, type of fabrics, laundering, hydration, stretch, fabric processing, UV absorbers, color, and fabric-to-skin distance.

  5. Glass--Sand + Imagination

    NASA Astrophysics Data System (ADS)

    Kolb, Kenneth E.; Kolb, Doris K.

    2000-07-01

    Glass is older than recorded history, and yet it is as new as tomorrow! How, when, or where man first learned to make glass is not known, but we do know that the ancient Egyptians were making glass articles as early as 2,600 B.C.E. (The making of glass beads may have begun as much as 3000 years earlier.) They used it to make jewelry and luxury items, such as decorative bowls and perfume bottles, available only to the wealthy.

  6. Reframing the Glass Ceiling as a Socially Constructed Process: Implications for Understanding and Change.

    ERIC Educational Resources Information Center

    Buzzanell, Patrice M.

    1995-01-01

    Argues that traditional definitions of "glass ceiling" perpetuate gender-biased organizational practices and create an illusion of women's opportunity, preventing critical assessment of contemporary organizational practices and of gendered communication. Creates awareness of unjust organizing processes by juxtaposing the ordinary ways of "doing…

  7. Gender, Gender Role, and Body Image.

    ERIC Educational Resources Information Center

    Jackson, Linda A.; And Others

    This study examined the importance of gender and gender role in understanding self-perceptions of body image. Male and female college students (N=166) who differed in gender role as measured by the Bem Sex Role Inventory completed the Body-Self Relations Questionnaire, a new measure of body image containing 140 items which fit a 3 x 3 matrix that…

  8. Determinant factors of gender identity: a commentary.

    PubMed

    Liao, Lih-Mei; Audi, Laura; Magritte, Ellie; Meyer-Bahlburg, Heino F L; Quigley, Charmian A

    2012-12-01

    Paediatric specialists involved in the care of children with disorders of sex development may be expected to provide straightforward answers to questions concerning the "true sex" of a child, reflecting common perceptions of sex/gender as an immutable binary biological reality. This article highlights how much more broad and complex the topic of gender identity and its development is. Many theories have been put forward to advance knowledge of gender identity. Against the breadth and depth of this vast topic, the current overview is inevitably incomplete. It begins by arguing for a more consistent use of 'sex' and 'gender'. It considers in turn three influential theoretical frameworks that lend themselves to empirical research. These are: 1) the role of the brain; 2) the role of socialisation; and 3) multi-dimensional gender development. The article ends by suggesting potentially fruitful questions and areas for future research.

  9. Rare Earth Phosphate Glass and Glass-Ceramic Proton Conductors

    SciTech Connect

    De Jonghe, Lutgard C.; Ray, Hannah L.; Wang, Ruigang

    2008-12-03

    The structure and conductivity of cerium and lanthanum phosphate glasses and glass-ceramics were investigated. The effects of varying the metal to phosphate ratio in the glasses, doping LaP3O9 glasses with Ce, and recrystallization of CeP3O9 glasses, on the glasses' microstructure and total conductivity were investigated using XRD, SEM, and AC impedance techniques. Strong increases in conductivity occurred when the glasses were recrystallized: the conductivity of a cerium metaphosphate glass increased conductivity after recrystallization from 10-7.5 S/cm to 10-6 S/cm at 400oC.

  10. Lanthanoides in Glass and Glass Ceramics

    NASA Astrophysics Data System (ADS)

    Meinhardt, Jürgen; Kilo, Martin; Somorowsky, Ferdinand; Hopp, Werner

    2017-03-01

    Many types of glass contain lanthanoides; among them, special glass for optical applications is the one with the highest content of lanthanoides. The precise determination of the lanthanoides' concentration is performed by inductively coupled plasma-optical emission spectrometry (ICP-OES). However, up to now, there are no established standard processes guaranteeing a uniform approach to the lanthanoide analysis. The knowledge of the lanthanoides' concentrations is necessary on the microscale in some cases, especially if a suitable separation and recycling procedure is to be applied. Here, the analysis is performed by energy-dispersive X-ray (EDX) or wavelength-dispersive X-ray (WDX) analytics in the scanning electron microscope.

  11. Glasses and Contact Lenses

    MedlinePlus

    ... about special eyewear you can wear on the field. With glasses, you'll also want to find out how to clean them properly. And it helps if you have a glasses case and put them in it when you're not wearing them. The last thing you want is to sit on your ...

  12. Glasses and Contact Lenses

    MedlinePlus

    ... Real Lifesaver Kids Talk About: Coaches Glasses and Contact Lenses KidsHealth > For Kids > Glasses and Contact Lenses Print A A A What's in this ... together the way they should. But eyeglasses or contact lenses, also called corrective lenses, can help most ...

  13. Getting Started with Glass

    ERIC Educational Resources Information Center

    White, Heather

    2007-01-01

    The metamorphosis of glass when heated is a magical process to students, yet teachers are often reluctant to try it in class. The biggest challenge in working with glass in the classroom is to simplify procedures just enough to ensure student success while maintaining strict safety practices so no students are injured. Project concepts and safety…

  14. Getting Started with Glass

    ERIC Educational Resources Information Center

    White, Heather

    2007-01-01

    The metamorphosis of glass when heated is a magical process to students, yet teachers are often reluctant to try it in class. The biggest challenge in working with glass in the classroom is to simplify procedures just enough to ensure student success while maintaining strict safety practices so no students are injured. Project concepts and safety…

  15. Two hundred glass injuries.

    PubMed Central

    Bell, D

    1984-01-01

    Two hundred children with glass injuries were investigated; 48 were injured in falls through architectural glass and 87 by broken bottles. Nine children had serious lacerations--7 of which were sustained at home. Radiographs were important in diagnosing retained fragments but prophylactic antibiotics were unnecessary. Many injuries could have been prevented by more stringent safety measures. PMID:6465940

  16. Glass-Ampoule Breaker

    NASA Technical Reports Server (NTRS)

    Christianson, R. C.; Kaushik, Surender M.; Davis, Dennis D.

    1995-01-01

    Device breaks glass ampoule in repeatable manner and retains gaseous content so pressure of gas measured accurately. In addition, protects technician from gaseous contents, which can be hazardous. Broken glass and sample materials easily removed for disposal or analysis. Apparatus developed for use in experiments on compatibility of materials.

  17. Surface Conductive Glass.

    ERIC Educational Resources Information Center

    Tanaka, John; Suib, Steven L.

    1984-01-01

    Discusses the properties of surface-conducting glass and the chemical nature of surface-conducting stannic (tin) oxide. Also provides the procedures necessary for the preparation of surface-conducting stannic oxide films on glass substrates. The experiment is suitable for the advanced inorganic chemistry laboratory. (JN)

  18. Dramatic Stained Glass.

    ERIC Educational Resources Information Center

    Prater, Michael

    2002-01-01

    Describes an art project that is appropriate for students in fifth through twelfth grade in which they create Gothic-style stained-glass windows. Discusses how college students majoring in elementary education created stained-glass windows. Addresses how to adapt this lesson for younger students. (CMK)

  19. Optical and Mechanical Properties of Glass Blown In Vacuo

    NASA Technical Reports Server (NTRS)

    Manning, andrew; Tucker, Dennis; Mooney, Theodore; Herren, Kenneth; Gregory, Don A.

    2006-01-01

    Theoretically, the strength of glass processed in vacuum should be higher due to outgassing of contaminants normally present in the glass, such as bulk water in the form of OH bonds that tends to weaken the glass structure. In this research, small discs of a few types of glass have been subjected to various temperatures for extended periods of time in vacuum. Their strength was then tested using a standard flexure technique, facilitated by a custom-designed test fixture, and the results were compared to glass tested in air using the same fixture. The purpose of the glass blowing investigation was to prove the basic feasibility of a high-level concept for in-space manufacture of optical elements. The central requirement was that the glass bubble had to be blown into a support structure such that the bubble could be handled by manipulation of the structure. The blown bubble attached itself to a mullite ring geometrically and mechanically, as a demonstration in the initial experiments described here, by expanding through and around it. The vacuum system used was custom made, as were most of the components of the system, such as the heating element, the glass and ring support structure, and the gas inlet system that provided the pressure needed to blow the glass.

  20. Optical and Mechanical Properties of Glass Blown In Vacuo

    NASA Technical Reports Server (NTRS)

    Manning, andrew; Tucker, Dennis; Mooney, Theodore; Herren, Kenneth; Gregory, Don A.

    2006-01-01

    Theoretically, the strength of glass processed in vacuum should be higher due to outgassing of contaminants normally present in the glass, such as bulk water in the form of OH bonds that tends to weaken the glass structure. In this research, small discs of a few types of glass have been subjected to various temperatures for extended periods of time in vacuum. Their strength was then tested using a standard flexure technique, facilitated by a custom-designed test fixture, and the results were compared to glass tested in air using the same fixture. The purpose of the glass blowing investigation was to prove the basic feasibility of a high-level concept for in-space manufacture of optical elements. The central requirement was that the glass bubble had to be blown into a support structure such that the bubble could be handled by manipulation of the structure. The blown bubble attached itself to a mullite ring geometrically and mechanically, as a demonstration in the initial experiments described here, by expanding through and around it. The vacuum system used was custom made, as were most of the components of the system, such as the heating element, the glass and ring support structure, and the gas inlet system that provided the pressure needed to blow the glass.

  1. Indium fluoride glass fibers

    NASA Astrophysics Data System (ADS)

    Saad, Mohammed

    2012-03-01

    Fluoride glasses are the only material that transmit light from ultraviolet to mid-infrared and can be drawn into industrial optical fibers. The mechanical and optical properties of new indium fluoride glass fibers have been investigated. Multimode fiber 190 microns, has very high mechanical strength greater than 100 kpsi and optical loss as low as 45 dB/km between 2 and 4 microns. Unlike chalcogenide glass fibers, indium fluoride fiber has a wide transmission window from 0.3 to 5.5 microns without any absorption peak. Indium fluoride glass fibers are the technology of choice for all application requiring transmission up to 5 micron such as infrared contour measure (IRCM) and chemical sensing. Furthermore, Indium fluoride glasses have low phonon energy and can be heavily doped and co-doped whit rare-earth elements. Therefore they are very promising candidates for infrared fiber lasers.

  2. Disorders of sex development and gender identity outcome in adolescence and adulthood: understanding gender identity development and its clinical implications.

    PubMed

    de Vries, Annelou L C; Doreleijers, Theo A H; Cohen-Kettenis, Peggy T

    2007-06-01

    This article reviews studies on gender identity outcome in individuals with disorders of sex development (DSD). It appears that a high percentage of affected individuals suffer from gender dysphoria. However, these figures differ substantially among the various DSD and they never reach 100%. From the studies it also becomes clear that a distinction should be made between gender role behavior and gender identity. Put in a broader theoretical framework, there is now more evidence that biological factors influence the development of gender role behavior than gender identity. Developmental psychology studies add evidence that social and psychological factors play a role as well in gender development. Clinicians should be aware of, but not overestimate the influences of neurobiological factors in gender development.

  3. Think crisis-think female: the glass cliff and contextual variation in the think manager-think male stereotype.

    PubMed

    Ryan, Michelle K; Haslam, S Alexander; Hersby, Mette D; Bongiorno, Renata

    2011-05-01

    The "think manager-think male" (TMTM) association underlies many gender inequalities in the workplace. However, research into the "glass cliff" has demonstrated that the suitability of male and female managers varies as a function of company performance such that in times of poor performance people may "think female" (Ryan & Haslam, 2005, 2007). Three studies examined gender and managerial stereotypes in the context of companies that are doing well or doing badly. Study 1 reproduced TMTM associations for descriptions of managers of successful companies but demonstrated a reversal for managers of unsuccessful companies. Study 2 examined the prescriptive nature of these stereotypes. No TMTM relationship was found for ideal managers of successful companies, but ideal managers of unsuccessful companies were associated with the female stereotype. Study 3 suggested that women may be favored in times of poor performance, not because they are expected to improve the situation, but because they are seen to be good people managers and can take the blame for organizational failure. Together, the studies illustrate the importance of context as a moderator of the TMTM association. Practical and theoretical implications for gender discrimination in the workplace are discussed.

  4. Photoprotection by window glass, automobile glass, and sunglasses.

    PubMed

    Tuchinda, Chanisada; Srivannaboon, Sabong; Lim, Henry W

    2006-05-01

    In daily activity, much time is spent indoors and in vehicles. Although the adverse effect of ultraviolet (UV) radiation is now well recognized and active public education programs on photoprotection have been undertaken, the role of window glass in photoprotection has been rarely addressed. It has been known for some time that window glass filters out UVB and transmits UVA and visible light. Recent developments in the glass industry have resulted in glass that provides broad UV protection without the historically associated loss of visible light transmission. Factors affecting UV-protective properties of glass are glass type, glass color, interleave between glass, and glass coating. In this article, photoprotection by window glass, automobile glass, and sunglasses is reviewed.

  5. Defense HLW Glass Degradation Model

    SciTech Connect

    D. Strachan

    2004-10-20

    The purpose of this report is to document the development of a model for calculating the release rate for radionuclides and other key elements from high-level radioactive waste (HLW) glasses under exposure conditions relevant to the performance of the repository. Several glass compositions are planned for the repository, some of which have yet to be identified (i.e., glasses from Hanford and Idaho National Engineering and Environmental Laboratory). The mechanism for glass dissolution is the same for these glasses and the glasses yet to be developed for the disposal of DOE wastes. All of these glasses will be of a quality consistent with the glasses used to develop this report.

  6. Study of diffusion coefficients of glasses under Zero-G

    NASA Technical Reports Server (NTRS)

    Kinser, D. L.

    1977-01-01

    A diffusion experiment for glasses was formulated, such theoretical and earth bound results as were available were outlined, and the preliminary earth based experimental work in preparation for a weightless experiment was done. The fundamental premise of the work was that diffusion studies of the glass forming ion can be conducted in zero-g environments, and diffusion data obtained from these experiments are unique and valuable because of earth based experimental difficulties.

  7. Assessment of water/glass interactions in waste glass melter operation

    SciTech Connect

    Postma, A.K.; Chapman, C.C.; Buelt, J.L.

    1980-04-01

    A study was made to assess the possibility of a vapor explosion in a liquid-fed glass melter and during off-standard conditions for other vitrification processes. The glass melter considered is one designed for the vitrification of high-level nuclear wastes and is comprised of a ceramic-lined cavity with electrodes for joule heating and processing equipment required to add feed and withdraw glass. Vapor explosions needed to be considered because experience in other industrial processes has shown that violent interactions can occur if a hot liquid is mixed with a cooler, vaporizable liquid. Available experimental evidence and theoretical analyses indicate that destructive glass/water interactions are low probability events, if they are possible at all. Under standard conditions, aspects of liquid-fed melter operation which work against explosive interactions include: (1) the aqueous feed is near its boiling point; (2) the feed contains high concentrations of suspended particles; (3) molten glass has high viscosity (greater than 20 poise); and (4) the glass solidifies before film boiling can collapse. While it was concluded that vapor explosions are not expected in a liquid-fed melter, available information does not allow them to be ruled out altogether. Several precautionary measures which are easily incorporated into melter operation procedures were identified and additional experiments were recommended.

  8. Atomic-Scale Mechanisms of the Glass-Forming Ability in Metallic Glasses

    NASA Astrophysics Data System (ADS)

    Yang, L.; Guo, G. Q.; Chen, L. Y.; Huang, C. L.; Ge, T.; Chen, D.; Liaw, P. K.; Saksl, K.; Ren, Y.; Zeng, Q. S.; LaQua, B.; Chen, F. G.; Jiang, J. Z.

    2012-09-01

    The issue, composition dependence of glass-forming ability (GFA) in metallic glasses (MG), has been investigated by systematic experimental measurements coupled with theoretical calculations in Cu-Zr and Ni-Nb alloy systems. It is found that the atomic-level packing efficiency strongly relates to their GFA. The best GFA is located at the largest difference in the packing efficiency of the solute-centered clusters between the glassy and crystal alloys in both MG systems. This work provides an understanding of GFA from atomic level and will shed light on the development of new MGs with larger critical sizes.

  9. Surface tension driven flow in glass melts and model fluids

    NASA Technical Reports Server (NTRS)

    Mcneil, T. J.; Cole, R.; Subramanian, R. S.

    1982-01-01

    Surface tension driven flow has been investigated analytically and experimentally using an apparatus where a free column of molten glass or model fluids was supported at its top and bottom faces by solid surfaces. The glass used in the experiments was sodium diborate, and the model fluids were silicone oils. In both the model fluid and glass melt experiments, conclusive evidence was obtained to prove that the observed flow was driven primarily by surface tension forces. The experimental observations are in qualitative agreement with predictions from the theoretical model.

  10. Surface tension driven flow in glass melts and model fluids

    NASA Technical Reports Server (NTRS)

    Mcneil, T. J.; Cole, R.; Subramanian, R. S.

    1982-01-01

    Surface tension driven flow has been investigated analytically and experimentally using an apparatus where a free column of molten glass or model fluids was supported at its top and bottom faces by solid surfaces. The glass used in the experiments was sodium diborate, and the model fluids were silicone oils. In both the model fluid and glass melt experiments, conclusive evidence was obtained to prove that the observed flow was driven primarily by surface tension forces. The experimental observations are in qualitative agreement with predictions from the theoretical model.

  11. Shock temperatures in anorthite glass

    SciTech Connect

    Boslough, M.B.; Ahrens, T.J.; Mitchell, A.C.

    1983-01-01

    Temperatures of CaAl2Si2O8 (anorthite glass) shocked to pressures between 48 and 117 GPa were measured in the range from 2500 to 5600 K, using optical pyrometry techniques. The pressure dependence of the shock temperatures deviates significantly from predictions based on a single high pressure phase. At least three phase transitions, at pressures of about 55, 85, and 100 GPa and with transition energies of about 0.5 MJ/kg each (approximately 1.5 MJ/kg total) are required to explain the shock temperature data. The phase transition at 100 GPa can possibly be identified with the stishovite melting transition. Theoretical models of the time dependence of the thermal radiation from the shocked anorthite based on the geometry of the experiment and the absorptive properties of the shocked material yields good agreement with observations, indicating that it is not necessary to invoke intrinsic time dependences to explain the data in many cases.

  12. Shock temperatures in anorthite glass

    NASA Technical Reports Server (NTRS)

    Boslough, M. B.; Ahrens, T. J.; Mitchell, A. C.

    1983-01-01

    Temperatures of CaAl2Si2O8 (anorthite glass) shocked to pressures between 48 and 117 GPa were measured in the range from 2500 to 5600 K, using optical pyrometry techniques. The pressure dependence of the shock temperatures deviates significantly from predictions based on a single high pressure phase. At least three phase transitions, at pressures of about 55, 85, and 100 GPa and with transition energies of about 0.5 MJ/kg each (approximately 1.5 MJ/kg total) are required to explain the shock temperature data. The phase transition at 100 GPa can possibly be identified with the stishovite melting transition. Theoretical models of the time dependence of the thermal radiation from the shocked anorthite based on the geometry of the experiment and the absorptive properties of the shocked material yields good agreement with observations, indicating that it is not necessary to invoke intrinsic time dependences to explain the data in many cases.

  13. Effect of different glasses in glass bonded zeolite

    SciTech Connect

    Lewis, M.A.; Ackerman, J.P.; Verma, S.

    1995-05-01

    A mineral waste form has been developed for chloride waste salt generated during the pyrochemical treatment of spent nuclear fuel. The waste form consists of salt-occluded zeolite powders bound within a glass matrix. The zeolite contains the salt and immobilizes the fission products. The zeolite powders are hot pressed to form a mechanically stable, durable glass bonded zeolite. Further development of glass bonded zeolite as a waste form requires an understanding of the interaction between the glass and the zeolite. Properties of the glass that enhance binding and durability of the glass bonded zeolite need to be identified. Three types of glass, boroaluminosilicate, soda-lime silicate, and high silica glasses, have a range of properties and are now being investigated. Each glass was hot pressed by itself and with an equal amount of zeolite. MCC-1 leach tests were run on both. Soda-lime silicate and high silica glasses did not give a durable glass bonded zeolite. Boroaluminosilicate glasses rich in alkaline earths did bind the zeolite and gave a durable glass bonded zeolite. Scanning electron micrographs suggest that the boroaluminosilicate glasses wetted the zeolite powders better than the other glasses. Development of the glass bonded zeolite as a waste form for chloride waste salt is continuing.

  14. Glass electrolyte composition

    DOEpatents

    Kucera, G.H.; Roche, M.F.

    1985-01-08

    An ionically conductive glass is disclosed for use as electrolyte in a high temperature electrochemical cell, particularly a cell with sodium anode and sulfur cathode. The glass includes the constituents Na/sub 2/O, ZrO/sub 2/, Al/sub 2/O/sub 3/ and SiO/sub 2/ in selected proportions to be a single phase solid solution substantially free of crystalline regions and undissolved constituents. Other advantageous properties are an ionic conductivity in excess of 2 x 10/sup -3/ (ohm-cm)/sup -1/ at 300/sup 0/C and a glass transition temperature in excess of 500/sup 0/C.

  15. Glass electrolyte composition

    DOEpatents

    Kucera, Gene H.; Roche, Michael F.

    1985-01-01

    An ionically conductive glass is disclosed for use as electrolyte in a high temperature electrochemical cell, particularly a cell with sodium anode and sulfur cathode. The glass includes the constituents Na.sub.2 O, ZrO.sub.2, Al.sub.2 O.sub.3 and SiO.sub.2 in selected proportions to be a single phase solid solution substantially free of crystalline regions and undissolved constituents. Other advantageous properties are an ionic conductivity in excess of 2.times.10.sup.-3 (ohm-cm).sup.-1 at 300.degree. C. and a glass transition temperature in excess of 500.degree. C.

  16. Making Theory Relevant: The Gender Attitude and Belief Inventory

    ERIC Educational Resources Information Center

    McCabe, Janice

    2013-01-01

    This article describes and evaluates the Gender Attitude and Belief Inventory (GABI), a teaching tool designed to aid students in (a) realizing how sociological theory links to their personal beliefs and (b) exploring any combination of 11 frequently used theoretical perspectives on gender, including both conservative theories (physiological,…

  17. The Intrapsychics of Gender: A Model of Self-Socialization

    ERIC Educational Resources Information Center

    Tobin, Desiree D.; Menon, Meenakshi; Menon, Madhavi; Spatta, Brooke C.; Hodges, Ernest V. E.; Perry, David G.

    2010-01-01

    This article outlines a model of the structure and the dynamics of gender cognition in childhood. The model incorporates 3 hypotheses featured in different contemporary theories of childhood gender cognition and unites them under a single theoretical framework. Adapted from Greenwald et al. (2002), the model distinguishes three constructs: gender…

  18. Gendered Hegemony and Its Contradictions among Finnish University Physicists

    ERIC Educational Resources Information Center

    Sannino, Annalisa; Vainio, Jenny

    2015-01-01

    This article addresses the issue of gender imbalance in Finnish universities in the domain of physics as a historical and dialectical phenomenon. Drawing from the Gramscian notion of hegemony and the activity-theoretical notion of contradiction, this paper analyses gendered hegemonic and contradictory forces steering physicists' careers. This…

  19. Gendered Hegemony and Its Contradictions among Finnish University Physicists

    ERIC Educational Resources Information Center

    Sannino, Annalisa; Vainio, Jenny

    2015-01-01

    This article addresses the issue of gender imbalance in Finnish universities in the domain of physics as a historical and dialectical phenomenon. Drawing from the Gramscian notion of hegemony and the activity-theoretical notion of contradiction, this paper analyses gendered hegemonic and contradictory forces steering physicists' careers. This…

  20. Making Theory Relevant: The Gender Attitude and Belief Inventory

    ERIC Educational Resources Information Center

    McCabe, Janice

    2013-01-01

    This article describes and evaluates the Gender Attitude and Belief Inventory (GABI), a teaching tool designed to aid students in (a) realizing how sociological theory links to their personal beliefs and (b) exploring any combination of 11 frequently used theoretical perspectives on gender, including both conservative theories (physiological,…

  1. The Intrapsychics of Gender: A Model of Self-Socialization

    ERIC Educational Resources Information Center

    Tobin, Desiree D.; Menon, Meenakshi; Menon, Madhavi; Spatta, Brooke C.; Hodges, Ernest V. E.; Perry, David G.

    2010-01-01

    This article outlines a model of the structure and the dynamics of gender cognition in childhood. The model incorporates 3 hypotheses featured in different contemporary theories of childhood gender cognition and unites them under a single theoretical framework. Adapted from Greenwald et al. (2002), the model distinguishes three constructs: gender…

  2. Breaking Through the Glass Ceiling: Recent Experimental Approaches to Probe the Properties of Supercooled Liquids near the Glass Transition.

    SciTech Connect

    Smith, R. Scott; Kay, Bruce D.

    2012-03-15

    Experimental measurements of the properties supercooled liquids at temperatures near their respective glass transition temperatures, Tg, are requisite for understanding the behavior of glasses and amorphous solids. Unfortunately, many supercooled molecular liquids rapidly crystallize at temperatures far above their Tg making such measurements difficult to nearly impossible. In this perspective we discuss some recent alternative approaches to obtain experimental data in the temperature regime near Tg. These new approaches may yield the additional experimental data necessary to test current theoretical models of the dynamical slowdown that occurs in supercooled liquids approaching the glass transition.

  3. Breaking Through the Glass Ceiling: Recent Experimental Approaches to Probe the Properties of Supercooled Liquids near the Glass Transition.

    PubMed

    Smith, R Scott; Kay, Bruce D

    2012-03-15

    Experimental measurements of the properties of supercooled liquids at temperatures near their glass transition temperatures, Tg, are requisite for understanding the behavior of glasses and amorphous solids. Unfortunately, many supercooled molecular liquids rapidly crystallize at temperatures far above their Tg, making such measurements difficult to nearly impossible. In this Perspective, we discuss some recent alternative approaches to obtain experimental data in the temperature regime near Tg. These new approaches may yield the additional experimental data necessary to test current theoretical models of the dynamical slowdown that occurs in supercooled liquids approaching the glass transition.

  4. Young Children, Gender and the Heterosexual Matrix

    ERIC Educational Resources Information Center

    Paechter, Carrie

    2017-01-01

    In this paper I consider the adult focus of current mainstream gender theory. I relate this to how the concept of the heterosexual matrix originates in a social contract which excludes children from civil society. I argue that this exclusion is problematic both for theoretical reasons and from the perspective of children themselves. I start by…

  5. Gender Inequality in British and German Universities

    ERIC Educational Resources Information Center

    Pritchard, Rosalind

    2007-01-01

    Gender inequality exists within higher education in the UK and Germany. In the UK only 15.3% of professors in pre-and post-1992 universities were women (2003), whilst in Germany only 8.6% attained the highest grade of professorship (2003). The research uses existing data sets combined with theoretical constructs to investigate the reasons for…

  6. Approaches to Gender and Spoken Classroom Discourse

    ERIC Educational Resources Information Center

    Sauntson, Helen

    2012-01-01

    Gender is a hotly debated topic in the field of education. The role that language plays in educational contexts especially in the classroom has long been acknowledged. Innovatively combining approaches in the analysis of classroom discourse, this book offers rich empirical findings as well as being theoretically interesting and valuable. (Contains…

  7. Gender Inequality in Undergraduate Business Schools: The Glass Door Effects

    ERIC Educational Resources Information Center

    Davis, Laura M.; Geyfman, Victoria

    2012-01-01

    This study examined female underrepresentation in business schools among undergraduate students and faculty in a sample of universities in the Pennsylvania State System of Higher Education and compares the findings to other public universities in Pennsylvania. We found that during the 1995-2008 period, when compared with other academic…

  8. Gender Inequality in Undergraduate Business Schools: The Glass Door Effects

    ERIC Educational Resources Information Center

    Davis, Laura M.; Geyfman, Victoria

    2012-01-01

    This study examined female underrepresentation in business schools among undergraduate students and faculty in a sample of universities in the Pennsylvania State System of Higher Education and compares the findings to other public universities in Pennsylvania. We found that during the 1995-2008 period, when compared with other academic…

  9. De-Emphasizing Gender in Talk about Texts: Literature Response, Discussion, and Gender within a Classroom Community of Practice

    ERIC Educational Resources Information Center

    Brendler, Beth Monica

    2012-01-01

    Drawing on and reexamining theories on gender and literacy, derived from research performed between 1974 and 2002, this qualitative study explored the gender assumptions and expectations of 19 preservice and practicing secondary language arts teachers in a graduate level adolescent literature course. The theoretical framework was structured around…

  10. De-Emphasizing Gender in Talk about Texts: Literature Response, Discussion, and Gender within a Classroom Community of Practice

    ERIC Educational Resources Information Center

    Brendler, Beth Monica

    2012-01-01

    Drawing on and reexamining theories on gender and literacy, derived from research performed between 1974 and 2002, this qualitative study explored the gender assumptions and expectations of 19 preservice and practicing secondary language arts teachers in a graduate level adolescent literature course. The theoretical framework was structured around…

  11. Glass for Solar Concentrators

    NASA Technical Reports Server (NTRS)

    Bouquet, F. L.

    1984-01-01

    Report identifies four commercially available glasses as promising reflectors for solar concentrators. Have properties of high reflectance (80 to 96 percent), lower cost than first-surface silver metalization, and resistance to environmental forces.

  12. Glass formation in microgravity

    NASA Technical Reports Server (NTRS)

    Ray, C. S.; Day, D. E.

    1987-01-01

    An account is given of containerless glass-forming experiments conducted aboard the Space Shuttle in 1985, using a single-axis acoustic levitator furnace apparatus. An attempt was made to obtain quantitative evidence for the suppression of heterogeneous nucleation/crystallization in containerless melts under microgravity conditions, as well as to study melt homogenization in the absence of gravity-driven convection and assess the feasibility of laser fusion target glass microsphere preparation with a microgravity apparatus of the present type. A ternary calcia-gallia-silica glass thus obtained indicated a 2-3-fold increase in glass-formation tendency for this material composition in microgravity, by comparison with 1g.

  13. Seeing Glass Contractors Clearly.

    ERIC Educational Resources Information Center

    Deliberato, Jerry

    2003-01-01

    Offers seven tips for finding and working with an effective glass contractor. For example, schools should consider the company's reputation and longevity of service, and whether it has in-house engineering capabilities. (EV)

  14. Glass Stronger than Steel

    DOE R&D Accomplishments Database

    Yarris, Lynn

    2011-03-28

    A new type of damage-tolerant metallic glass, demonstrating a strength and toughness beyond that of steel or any other known material, has been developed and tested by a collaboration of researchers from Berkeley Lab and Caltech.

  15. Super ionic conductive glass

    DOEpatents

    Susman, S.; Volin, K.J.

    Described is an ionically conducting glass for use as a solid electrolyte in a power or secondary cell containing an alkali metal-containing anode and a cathode separated by an alkali metal ion conducting glass having an ionic transference number of unity and the general formula: A/sub 1 + x/D/sub 2-x/3/Si/sub x/P/sub 3 - x/O/sub 12 - 2x/3/, wherein A is a network modifier for the glass and is an alkali metal of the anode, D is an intermediate for the glass and is selected from the class consisting of Zr, Ti, Ge, Al, Sb, Be, and Zn and X is in the range of from 2.25 to 3.0. Of the alkali metals, Na and Li are preferred and of the intermediate, Zr, Ti and Ge are preferred.

  16. Super ionic conductive glass

    DOEpatents

    Susman, Sherman; Volin, Kenneth J.

    1984-01-01

    An ionically conducting glass for use as a solid electrolyte in a power or secondary cell containing an alkali metal-containing anode and a cathode separated by an alkali metal ion conducting glass having an ionic transference number of unity and the general formula: A.sub.1+x D.sub.2-x/3 Si.sub.x P.sub.3-x O.sub.12-2x/3, wherein A is a network modifier for the glass and is an alkali metal of the anode, D is an intermediate for the glass and is selected from the class consisting of Zr, Ti, Ge, Al, Sb, Be, and Zn and X is in the range of from 2.25 to 3.0. Of the alkali metals, Na and Li are preferred and of the intermediate, Zr, Ti and Ge are preferred.

  17. Glass formation in microgravity

    NASA Technical Reports Server (NTRS)

    Ray, C. S.; Day, D. E.

    1987-01-01

    An account is given of containerless glass-forming experiments conducted aboard the Space Shuttle in 1985, using a single-axis acoustic levitator furnace apparatus. An attempt was made to obtain quantitative evidence for the suppression of heterogeneous nucleation/crystallization in containerless melts under microgravity conditions, as well as to study melt homogenization in the absence of gravity-driven convection and assess the feasibility of laser fusion target glass microsphere preparation with a microgravity apparatus of the present type. A ternary calcia-gallia-silica glass thus obtained indicated a 2-3-fold increase in glass-formation tendency for this material composition in microgravity, by comparison with 1g.

  18. Gender, smoking and tobacco reduction and cessation: a scoping review.

    PubMed

    Bottorff, Joan L; Haines-Saah, Rebecca; Kelly, Mary T; Oliffe, John L; Torchalla, Iris; Poole, Nancy; Greaves, Lorraine; Robinson, Carole A; Ensom, Mary H H; Okoli, Chizimuzo T C; Phillips, J Craig

    2014-12-12

    Considerations of how gender-related factors influence smoking first appeared over 20 years ago in the work of critical and feminist scholars. This scholarship highlighted the need to consider the social and cultural context of women's tobacco use and the relationships between smoking and gender inequity. Parallel research on men's smoking and masculinities has only recently emerged with some attention being given to gender influences on men's tobacco use. Since that time, a multidisciplinary literature addressing women and men's tobacco use has spanned the social, psychological and medical sciences. To incorporate these gender-related factors into tobacco reduction and cessation interventions, our research team identified the need to clarify the current theoretical and methodological interpretations of gender within the context of tobacco research. To address this need a scoping review of the published literature was conducted focussing on tobacco reduction and cessation from the perspective of three aspects of gender: gender roles, gender identities, and gender relations. Findings of the review indicate that there is a need for greater clarity on how researchers define and conceptualize gender and its significance for tobacco control. Patterns and anomalies in the literature are described to guide the future development of interventions that are gender-sensitive and gender-specific. Three principles for including gender-related factors in tobacco reduction and cessation interventions were identified: a) the need to build upon solid conceptualizations of gender, b) the importance of including components that comprehensively address gender-related influences, and c) the importance of promoting gender equity and healthy gender norms, roles and relations.

  19. Metallic glass composition

    DOEpatents

    Kroeger, Donald M.; Koch, Carl C.

    1986-01-01

    A metallic glass alloy that is either iron-based or nickel-based or based on a mixture of iron and nickel, containing lesser amounts of elements selected from the group boron, silicon carbon and phosphorous to which is added an amount of a ductility enhancing element selected from the group cerium, lanthanum, praseodymium and neodymium sufficient to increase ductility of the metallic glass upon annealing.

  20. Frangible glass canisters

    NASA Technical Reports Server (NTRS)

    Seifert, R.

    1972-01-01

    The need for a canister that can release its contents without disturbing the contents dynamically is discussed. The solution of this problem by the use of a frangible glass canister is considered. The basic theory applicable to frangible glass and the method of initiating a command flaw are discussed. A brief description of the test program and the results of a flight test are presented.

  1. Glass fiber insulation

    SciTech Connect

    Griffith, E.J.; Ngo, T.M.

    1993-06-29

    A composition for a glass fiber insulation is described comprising a loose mat of glass fibers having at least a portion of the surface coated with a water insoluble, non-hygroscopic, amorphous aluminum phosphate polymer having a molar ratio of Al[sub 2]O[sub 3] to P[sub 2]O[sub 5] of less than 1 and providing a substantial thermal resistance.

  2. Display innovations through glass

    NASA Astrophysics Data System (ADS)

    Hamilton, Lori L.

    2016-03-01

    Prevailing trends in thin, lightweight, high-resolution, and added functionality, such as touch sensing, continue to drive innovation in the display market. While display volumes grow, so do consumers’ need for portability, enhanced optical performance, and mechanical reliability. Technical advancements in glass design and process have enabled display innovations in these areas while supporting industry growth. Opportunities for further innovation remain open for glass manufacturers to drive new applications, enhanced functionality, and increased demand.

  3. Baseline LAW Glass Formulation Testing

    SciTech Connect

    Kruger, Albert A.; Mooers, Cavin; Bazemore, Gina; Pegg, Ian L.; Hight, Kenneth; Lai, Shan Tao; Buechele, Andrew; Rielley, Elizabeth; Gan, Hao; Muller, Isabelle S.; Cecil, Richard

    2013-06-13

    The major objective of the baseline glass formulation work was to develop and select glass formulations that are compliant with contractual and processing requirements for each of the LAW waste streams. Other objectives of the work included preparation and characterization of glasses with respect to the properties of interest, optimization of sulfate loading in the glasses, evaluation of ability to achieve waste loading limits, testing to demonstrate compatibility of glass melts with melter materials of construction, development of glass formulations to support ILAW qualification activities, and identification of glass formulation issues with respect to contract specifications and processing requirements.

  4. Method for making glass nonfogging

    DOEpatents

    Lord, David E.; Carter, Gary W.; Petrini, Richard R.

    1979-01-01

    A method for rendering glass nonfogging (to condensation fog) by sandwiching the glass between two electrodes such that the glass functions as the dielectric of a capacitor, a large alternating current (AC) voltage is applied across the electrodes for a selected time period causing the glass to absorb a charge, and the electrodes are removed. The glass absorbs a charge from the electrodes rendering it nonfogging. The glass surface is undamaged by application of the AC voltage, and normal optical properties are unaffected. This method can be applied to optical surfaces such as lenses, auto windshields, mirrors, etc., wherever condensation fog on glass is a problem.

  5. Lacerations from glass in childhood.

    PubMed Central

    Jackson, R H

    1981-01-01

    A study of 62 glass injuries to children serious enough to warrant admission to hospital showed that 30 were due to architectural glass in doors or windows and 26 of these occurred in houses. Glass bottles caused 12 injuries. Architectural glass produced more serious injuries affecting major arteries, nerves and tendons, and internal viscera. In view of the frequency and severity of architectural glass injuries in houses, safety glass in recommended for all glass doors, French windows, patio doors, and the lower parts of windows. Images FIG 1 FIG 2 FIG 3 PMID:6794836

  6. Effective diffraction gratings via acidic etching of thermally poled glass

    NASA Astrophysics Data System (ADS)

    Kamenskii, A. N.; Reduto, I. V.; Petrikov, V. D.; Lipovskii, A. A.

    2016-12-01

    Relief diffraction gratings are formed via acidic chemical etching of a periodically poled soda-lime glass. The thermal poling under 1000 V DC is performed at 325 °C using a thermally stable glassy-carbon anodic electrode with periodic grooves, the depth of the grooves being of ∼650 nm. Poling-induced modification of the glass results in deepening the glass anodic surface in the regions under the ribs of the anodic electrode due to volume relaxation and in increasing chemical durability of these regions in acidic media comparatively to the virgin glass. Chemical etching of the poled glass in NH4F:8H2O solution allows additional to the thermal poling shaping of the glass surface via faster dissolution of unpoled/less poled glass regions. The morphology of the glass surface before and after the etching is characterized with atomic force and scanning electron microscopy. About 30 min etching provides the formation of ∼0.9 μm in height relief diffraction gratings with the diffraction efficiency close to the theoretically achievable ∼30% for multi-order diffraction. In vivo measuring of the diffraction efficiency in the course of the etching allows precise fabrication of the gratings.

  7. Computational fluid dynamics simulations of a glass melting furnace

    SciTech Connect

    Egelja, A.; Lottes, S. A.

    2000-05-09

    The glass production industry is one of the major users of natural gas in the US, and approximately 75% of the energy produced from natural gas is used in the melting process. Industrial scale glass melting furnaces are large devices, typically 5 or more meters wide, and twice as long. To achieve efficient heat transfer to the glass melt below, the natural gas flame must extend over a large portion of the glass melt. Therefore modern high efficiency burners are not used in these furnaces. The natural gas is injected as a jet, and a jet flame forms in the flow of air entering the furnace. In most current glass furnaces the energy required to melt the batch feed stock is about twice the theoretical requirement. An improved understanding of the heat transfer and two phase flow processes in the glass melt and solid batch mix offers a substantial opportunity for energy savings and consequent emission reductions. The batch coverage form and the heat flux distribution have a strong influence on the glass flow pattern. This flow pattern determines to a significant extent the melting rate and the quality of glass.

  8. Gender-related academic and occupational interests and goals.

    PubMed

    Petersen, Jennifer; Hyde, Janet Shibley

    2014-01-01

    This chapter reviews the theories and empirical evidence concerning whether gender differences in academic and occupational goals and interests exist, and if so, why those differences may be present. Expectancy-value theory, stereotype threat, sociocultural theory, and the gender similarities hypothesis lay the theoretical framework for this chapter. Following a brief review of these theories, we describe the evidence for gender differences in academic ability and occupational interests and goals, using meta-analytic reviews wherever possible. Although there are few gender differences in academic ability, some gender differences in occupational goals and interests persist, particularly in science and mathematics. These gender differences may be due to parental or cultural expectations, changes in developmental trends, stereotypes and discrimination, or gendered-expectations to achieve work-family balance. Overall, the pathways to adult occupations are complex, involving many factors that affect occupational goals, interests, and self-concept.

  9. Social cognitive theory of gender development and differentiation.

    PubMed

    Bussey, K; Bandura, A

    1999-10-01

    Human differentiation on the basis of gender is a fundamental phenomenon that affects virtually every aspect of people's daily lives. This article presents the social cognitive theory of gender role development and functioning. It specifies how gender conceptions are constructed from the complex mix of experiences and how they operate in concert with motivational and self-regulatory mechanisms to guide gender-linked conduct throughout the life course. The theory integrates psychological and sociostructural determinants within a unified conceptual structure. In this theoretical perspective, gender conceptions and roles are the product of a broad network of social influences operating interdependently in a variety of societal subsystems. Human evolution provides bodily structures and biological potentialities that permit a range of possibilities rather than dictate a fixed type of gender differentiation. People contribute to their self-development and bring about social changes that define and structure gender relationships through their agentic actions within the interrelated systems of influence.

  10. Perspective: The glass transition

    NASA Astrophysics Data System (ADS)

    Biroli, Giulio; Garrahan, Juan P.

    2013-03-01

    We provide here a brief perspective on the glass transition field. It is an assessment, written from the point of view of theory, of where the field is and where it seems to be heading. We first give an overview of the main phenomenological characteristics, or "stylised facts," of the glass transition problem, i.e., the central observations that a theory of the physics of glass formation should aim to explain in a unified manner. We describe recent developments, with a particular focus on real space properties, including dynamical heterogeneity and facilitation, the search for underlying spatial or structural correlations, and the relation between the thermal glass transition and athermal jamming. We then discuss briefly how competing theories of the glass transition have adapted and evolved to account for such real space issues. We consider in detail two conceptual and methodological approaches put forward recently, that aim to access the fundamental critical phenomenon underlying the glass transition, be it thermodynamic or dynamic in origin, by means of biasing of ensembles, of configurations in the thermodynamic case, or of trajectories in the dynamic case. We end with a short outlook.

  11. Nature, nurture, and core gender identity.

    PubMed

    Robbins, M

    1996-01-01

    Literature about gender differences and their possible origins, and contemporary psychoanalytic formulations of gender, is reviewed. There is a broad consensus among investigators from different fields, and among psychoanalysts of different theoretical persuasions, that the modal female personality tends to be more sociocentric, and the modal male personality more self-centric. These modal personality differences may be qualitative rather than quantitative. The concept of core gender identity, which articulates the psychological root of these differences, is reexamined in the light of contemporary research into constitutional differences in the organization and activation of the brain, and an interactional model of core gender identity as a dynamic evolving phenomenon over the course of the life cycle is proposed.

  12. Containerless synthesis of interesting glasses

    NASA Technical Reports Server (NTRS)

    Weinberg, Michael C.

    1990-01-01

    One aspect of containerless glass experimentation was thoroughly examined: glass forming ability. It is argued that although containerless processing will abet glass formation, other ground-based methods can do the job better. However, these methods have limitations, such as sample dimensions and concomitant ability to make property measurements. Most importantly, perhaps, is the observation that glass properties are a function of preparation procedure. Thus, it seems as though there still is an argument for use of containerless processing for glass forming.

  13. On the strength of glasses

    PubMed Central

    Wisitsorasak, Apiwat; Wolynes, Peter G.

    2012-01-01

    The remarkable strength of glasses is examined using the random first order transition theory of the glass transition. The theory predicts that strength depends on elastic modulus but also on the configurational energy frozen in when the glass is prepared. The stress catalysis of cooperative rearrangements of the type responsible for the supercooled liquid’s high viscosity account quantitatively for the measured strength of a range of metallic glasses, silica, and a polymer glass. PMID:22988070

  14. Doing gender in sex and sex research.

    PubMed

    Vanwesenbeeck, Ine

    2009-12-01

    Gender is central to sexuality, and vice versa, but there are a number of difficulties with the treatment of gender in sex research. Apparently, it is hard to find a balance between two conflicting needs. First, obviously, it is necessary to make distinctions between women and men, for political as well as research-technical and theoretical reasons. A second requirement, at odds with the first one, is the necessity to understand gender and its relation to sexuality and the body as much more complex than simplistically referring to two sets of individuals. This is all the more necessary when one realizes the possible drawbacks of exaggerating the differences between the sexes (in particular when they are biologically explained), because of stereotyping, stigmatizing, and expectancy confirmatory processes. This essay identifies and discusses 10 difficulties in the treatment of gender in sex research, reflects on their origins, and reviews theory and evidence with the aim to (1) consider the relative strength of gender/sex as an explanatory variable compared to other factors and processes explaining differences between men and women on a number of sexual aspects, (2) inform an understanding of gender and its relation to sexuality as an ongoing, open-ended, multi-determined, situated, interactional process, with the body as a third player, and (3) argue in favor of a nuanced, well-balanced treatment of gender in sex research.

  15. Glass microsphere lubrication

    NASA Technical Reports Server (NTRS)

    Geiger, Michelle; Goode, Henry; Ohanlon, Sean; Pieloch, Stuart; Sorrells, Cindy; Willette, Chris

    1991-01-01

    The harsh lunar environment eliminated the consideration of most lubricants used on earth. Considering that the majority of the surface of the moon consists of sand, the elements that make up this mixture were analyzed. According to previous space missions, a large portion of the moon's surface is made up of fine grained crystalline rock, about 0.02 to 0.05 mm in size. These fine grained particles can be divided into four groups: lunar rock fragments, glasses, agglutinates (rock particles, crystals, or glasses), and fragments of meteorite material (rare). Analysis of the soil obtained from the missions has given chemical compositions of its materials. It is about 53 to 63 percent oxygen, 16 to 22 percent silicon, 10 to 16 percent sulfur, 5 to 9 percent aluminum, and has lesser amounts of magnesium, carbon, and sodium. To be self-supporting, the lubricant must utilize one or more of the above elements. Considering that the element must be easy to extract and readily manipulated, silicon or glass was the most logical choice. Being a ceramic, glass has a high strength and excellent resistance to temperature. The glass would also not contaminate the environment as it comes directly from it. If sand entered a bearing lubricated with grease, the lubricant would eventually fail and the shaft would bind, causing damage to the system. In a bearing lubricated with a solid glass lubricant, sand would be ground up and have little effect on the system. The next issue was what shape to form the glass in. Solid glass spheres was the only logical choice. The strength of the glass and its endurance would be optimal in this form. To behave as an effective lubricant, the diameter of the spheres would have to be very small, on the order of hundreds of microns or less. This would allow smaller clearances between the bearing and the shaft, and less material would be needed. The production of glass microspheres was divided into two parts, production and sorting. Production includes the

  16. DWPF GLASS BEADS AND GLASS FRIT TRANSPORT DEMONSTRATION

    SciTech Connect

    Adamson, D; Bradley Pickenheim, B

    2008-11-24

    DWPF is considering replacing irregularly shaped glass frit with spherical glass beads in the Slurry Mix Evaporator (SME) process to decrease the yield stress of the melter feed (a non-Newtonian Bingham Plastic). Pilot-scale testing was conducted on spherical glass beads and glass frit to determine how well the glass beads would transfer when compared to the glass frit. Process Engineering Development designed and constructed the test apparatus to aid in the understanding and impacts that spherical glass beads may have on the existing DWPF Frit Transfer System. Testing was conducted to determine if the lines would plug with the glass beads and the glass frit slurry and what is required to unplug the lines. The flow loop consisted of vertical and horizontal runs of clear PVC piping, similar in geometry to the existing system. Two different batches of glass slurry were tested: a batch of 50 wt% spherical glass beads and a batch of 50 wt% glass frit in process water. No chemicals such as formic acid was used in slurry, only water and glass formers. The glass beads used for this testing were commercially available borosilicate glass of mesh size -100+200. The glass frit was Frit 418 obtained from DWPF and is nominally -45+200 mesh. The spherical glass beads did not have a negative impact on the frit transfer system. The transferring of the spherical glass beads was much easier than the glass frit. It was difficult to create a plug with glass bead slurry in the pilot transfer system. When a small plug occurred from setting overnight with the spherical glass beads, the plug was easy to displace using only the pump. In the case of creating a man made plug in a vertical line, by filling the line with spherical glass beads and allowing the slurry to settle for days, the plug was easy to remove by using flush water. The glass frit proved to be much more difficult to transfer when compared to the spherical glass beads. The glass frit impacted the transfer system to the point

  17. Workshop I: Gender Studies

    NASA Astrophysics Data System (ADS)

    Hennessey, Eden; Kurup, Anitha; Meza-Montes, Lilia; Shastri, Prajval; Ghose, Shohini

    2015-12-01

    Participants in the Gender Studies workshop of the 5th IUPAP International Conference on Women in Physics discussed the gender question in science practice from a policy perspective, informed by investigations from the social science disciplines. The workshop's three sessions—"Equity and Education: Examining Gender Stigma in Science," "A Comparative Study of Women Scientists and Engineers: Experiences in India and the US," and "Toward Gender Equity Through Policy: Characterizing the Social Impact of Interventions—are summarized, and the resulting recommendations presented.

  18. Gendered Educational and Occupational Choices: Applying the Eccles et al. Model of Achievement-Related Choices

    ERIC Educational Resources Information Center

    Eccles, Jacquelynne

    2011-01-01

    I summarize a theoretical model of the social, cultural, and psychological influences on achievement-related choices and outline how this model can help us understand gendered educational and occupational choices. I argue that both gender differences and individual differences within each gender in educational and occupational choices are linked…

  19. Gender Equity Report.

    ERIC Educational Resources Information Center

    Washington State Higher Education Coordinating Board, Olympia.

    This document reports on the implementation of two bills adopted by the Washington State legislature in 1989 to achieve gender equity in higher education. The gender equity statute prohibits discrimination on the basis of gender against any student, and, in particular, it forbids discrimination in student assistance and services, academic…

  20. Gender and Adolescent Development

    ERIC Educational Resources Information Center

    Perry, David G.; Pauletti, Rachel E.

    2011-01-01

    This article summarizes and critiques recent trends in research and theory on the role of gender in adolescent development. First, gender differences in key areas of adolescent functioning are reviewed. Second, research on 3 constructs that are especially relevant to the investigation of within-gender individual differences in gender…

  1. Gender Differences in Communication.

    ERIC Educational Resources Information Center

    Diedrick, Patricia

    Gender differences in spoken and unspoken emotional expression exist and may be related to gender differences in other realms, particularly in self-esteem. This literature review investigated gender differences in communication, particularly as related to emotional expressiveness, detection of emotional responses, and self-disclosures, in relation…

  2. Gender Effects in Parenting.

    ERIC Educational Resources Information Center

    Copeland, Anne P.; Grossman, Frances K.

    The literature on how parent gender influences responses to children has grown enormously in the past decade; mothers and fathers have been found to differ on many dimensions and to be similar on just as many. Conflicting evidence also exists on how a child's gender affects parenting style. This paper reports some important gender differences in…

  3. Beyond Gender Identity?

    ERIC Educational Resources Information Center

    Rasmussen, Mary Lou

    2009-01-01

    This paper focuses on the continuing significance of gender identity as a category of analysis within the field of gender theory and research in education. I begin by considering contemporary discussions of the limitations of research relating to gender theory and research in education. Following on from this, I explore some contemporary…

  4. The Embryology of Gender

    ERIC Educational Resources Information Center

    Jorge, Juan Carlos

    2010-01-01

    More than 50 years after the appearance of the term "gender" in the clinical setting, we have yet to uncover the mechanisms and factors that lead to gender identity formation. Based on human embryology principles, the scientific reasoning with regard to the sexual differentiation of the body is erroneously applied to gender identity formation. The…

  5. Gender and Higher Education

    ERIC Educational Resources Information Center

    Bank, Barbara J., Ed.

    2011-01-01

    This comprehensive, encyclopedic review explores gender and its impact on American higher education across historical and cultural contexts. Challenging recent claims that gender inequities in U.S. higher education no longer exist, the contributors--leading experts in the field--reveal the many ways in which gender is embedded in the educational…

  6. The Morpheme Gender Effect

    ERIC Educational Resources Information Center

    Meunier, Fanny; Seigneuric, Alix; Spinelli, Elsa

    2008-01-01

    In three experiments we explored the mental representation of morphologically complex words in French. Subjects were asked to perform a gender decision task on morphologically complex words that were of the same gender as their base or not. We found that gender decisions were made more slowly for morphologically complex words made from a base with…

  7. Gender and Science.

    PubMed

    2016-05-10

    We are delighted to expand our Cell Metabolism "Rosie project" to highlight an upcoming LabLinks meeting, "The Gender of Science and the Science of Gender" on May 19th in Cambridge, MA. We present the viewpoints of the speakers and other leaders on the ever-fascinating topic of gender in science. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Gender and Higher Education

    ERIC Educational Resources Information Center

    Bank, Barbara J., Ed.

    2011-01-01

    This comprehensive, encyclopedic review explores gender and its impact on American higher education across historical and cultural contexts. Challenging recent claims that gender inequities in U.S. higher education no longer exist, the contributors--leading experts in the field--reveal the many ways in which gender is embedded in the educational…

  9. Gender and Adolescent Development

    ERIC Educational Resources Information Center

    Perry, David G.; Pauletti, Rachel E.

    2011-01-01

    This article summarizes and critiques recent trends in research and theory on the role of gender in adolescent development. First, gender differences in key areas of adolescent functioning are reviewed. Second, research on 3 constructs that are especially relevant to the investigation of within-gender individual differences in gender…

  10. Schools Achieving Gender Equity.

    ERIC Educational Resources Information Center

    Revis, Emma

    This guide is designed to assist teachers presenting the Schools Achieving Gender Equity (SAGE) curriculum for vocational education students, which was developed to align gender equity concepts with the Kentucky Education Reform Act (KERA). Included in the guide are lesson plans for classes on the following topics: legal issues of gender equity,…

  11. Crystal nucleation in glass-forming alloy and pure metal melts under containerless and vibrationless conditions

    NASA Technical Reports Server (NTRS)

    Turnbull, D.

    1979-01-01

    Crystal nucleation behavior in metallic alloys known to form glasses in melt quenching was characterized and from this characterization the possibility that massive amounts of certain alloys could be slow cooled to the glass state was assessed. Crystal nucleation behavior of pure liquid metals was examined experimentally, under containerless conditions, and theoretically.

  12. Bose glass and Mott glass of quasiparticles in a doped quantum magnet.

    PubMed

    Yu, Rong; Yin, Liang; Sullivan, Neil S; Xia, J S; Huan, Chao; Paduan-Filho, Armando; Oliveira, Nei F; Haas, Stephan; Steppke, Alexander; Miclea, Corneliu F; Weickert, Franziska; Movshovich, Roman; Mun, Eun-Deok; Scott, Brian L; Zapf, Vivien S; Roscilde, Tommaso

    2012-09-20

    The low-temperature states of bosonic fluids exhibit fundamental quantum effects at the macroscopic scale: the best-known examples are Bose-Einstein condensation and superfluidity, which have been tested experimentally in a variety of different systems. When bosons interact, disorder can destroy condensation, leading to a 'Bose glass'. This phase has been very elusive in experiments owing to the absence of any broken symmetry and to the simultaneous absence of a finite energy gap in the spectrum. Here we report the observation of a Bose glass of field-induced magnetic quasiparticles in a doped quantum magnet (bromine-doped dichloro-tetrakis-thiourea-nickel, DTN). The physics of DTN in a magnetic field is equivalent to that of a lattice gas of bosons in the grand canonical ensemble; bromine doping introduces disorder into the hopping and interaction strength of the bosons, leading to their localization into a Bose glass down to zero field, where it becomes an incompressible Mott glass. The transition from the Bose glass (corresponding to a gapless spin liquid) to the Bose-Einstein condensate (corresponding to a magnetically ordered phase) is marked by a universal exponent that governs the scaling of the critical temperature with the applied field, in excellent agreement with theoretical predictions. Our study represents a quantitative experimental account of the universal features of disordered bosons in the grand canonical ensemble.

  13. The effect of liquid-liquid phase separation of glass on the properties and crystallization behavior

    NASA Technical Reports Server (NTRS)

    Li, J. Z.

    1985-01-01

    A theoretical discussion is given of the phase separation mechanism of amorphous materials. This includes nucleus growth, spinoidal decomposition, and nuclei agglomeration and coarsening. Various types of glass are analyzed.

  14. Environmental impact assessment in practice: A gender critique

    SciTech Connect

    Kurian, P.A. |

    1995-06-01

    The author evaluates the extent to which environmental impact assessment (EIA) as conceptualized by EIA systems is a gendered process. Through a discourse analysis of in-depth interviews with bureaucrats, technocrats, and activists involved with the Sardar Sarovar dam project in India, the author examines the practice of EIA in a Third World country. She uses a theoretical framework, informed by a theory of gender, to evaluate the interviews. In practice, EIA is marked by gender biases that ignore the gender-specific nature of impacts. Such biases distort the impact assessment process, making environmental sustainability difficult, if not impossible, to achieve.

  15. Glass matrix armor

    DOEpatents

    Calkins, Noel C.

    1991-01-01

    An armor system which utilizes glass. A plurality of constraint cells are mounted on a surface of a substrate, which is metal armor plate or a similar tough material, such that the cells almost completely cover the surface of the substrate. Each constraint cell has a projectile-receiving wall parallel to the substrate surface and has sides which are perpendicular to and surround the perimeter of the receiving wall. The cells are mounted such that, in one embodiment, the substrate surface serves as a sixth side or closure for each cell. Each cell has inside of it a plate, termed the front plate, which is parallel to and in contact with substantially all of the inside surface of the receiving wall. The balance of each cell is completely filled with a projectile-abrading material consisting of glass and a ceramic material and, in certain embodiments, a polymeric material. The glass may be in monolithic form or particles of ceramic may be dispersed in a glass matrix. The ceramic material may be in monolithic form or may be in the form of particles dispersed in glass or dispersed in said polymer.

  16. Sol-Gel Glasses

    NASA Technical Reports Server (NTRS)

    Mukherjee, S. P.

    1985-01-01

    Multicomponent homogeneous, ultrapure noncrystalline gels/gel derived glasses are promising batch materials for the containerless glass melting experiments in microgravity. Hence, ultrapure, homogeneous gel precursors could be used to: (1) investigate the effect of the container induced nucleation on the glass forming ability of marginally glass forming compositions; and (2) investigate the influence of gravity on the phase separation and coarsening behavior of gel derived glasses in the liquid-liquid immiscibility zone of the nonsilicate systems having a high density phase. The structure and crystallization behavior of gels in the SiO2-GeO2 as a function of gel chemistry and thermal treatment were investigated. As are the chemical principles involved in the distribution of a second network former in silica gel matrix being investigated. The procedures for synthesizing noncrystalline gels/gel-monoliths in the SiO2-GeO2, GeO2-PbO systems were developed. Preliminary investigations on the levitation and thermal treatment of germania silicate gel-monoliths in the Pressure Facility Acoustic Levitator were done.

  17. Microexplosions in tellurite glasses

    NASA Astrophysics Data System (ADS)

    Sundaram, S. K.; Schaffer, C. B.; Mazur, E.

    Femtosecond laser pulses were used to produce localized damage in the bulk and near the surface of baseline, Al2O3-doped and La2O3-doped sodium tellurite glasses. Single or multiple laser pulses were non-linearly absorbed in the focal volume by the glass, leading to permanent changes in the material in the focal volume. These changes were caused by an explosive expansion of the ionized material in the focal volume into the surrounding material, i.e. a microexplosion. The writing of simple structures (periodic array of voxels, as well as lines) was demonstrated. The regions of microexplosion and writing were subsequently characterized using scanning electron microscopy (SEM), energy-dispersive spectrometry (EDS) and atomic force microscopy (AFM). Fingerprints of microexplosions (concentric lines within the region and a concentric ring outside the region), due to the shock wave generated during microexplosions, were evident. In the case of the baseline glass, no chemistry change was observed within the region of the microexplosion. However, Al2O3-doped and La2O3-doped glasses showed depletion of the dopant from the edge to the center of the region of the microexplosions, indicating a chemistry gradient within the regions. Interrogation of the bulk- and laser-treated regions using micro-Raman spectroscopy revealed no structural change due to the microexplosions and writing within these glasses.

  18. Towards modeling gadolinium-lead-borate glasses

    SciTech Connect

    Rada, S.; Ristoiu, T.; Rada, M.; Coroiu, I.; Maties, V.; Culea, E.

    2010-01-15

    Infrared spectra of gadolinium-lead-borate glasses of the xGd{sub 2}O{sub 3}.(100 - x)[3B{sub 2}O{sub 3}.PbO] system, where x = 0, 5, 10, 15, 25, 35 and 50 mol.%, have been recorded to explore the role of content of gadolinium ions behaving as glass modifier. The FTIR spectroscopy data for the xGd{sub 2}O{sub 3}.(1 - x)[3B{sub 2}O{sub 3}.PbO] glasses show the structural role of lead ions as a network-formers and of the gadolinium ions network modifiers. Adding of the rare earth ion up to 35 mol.% into the glass matrix, the IR bands characteristic to the studied glasses become sharper and more pronounced. Structural changes, as recognized by analyzing band shapes of IR spectra, revealed that Gd{sub 2}O{sub 3} causes a change from the continuous borate network to the continuous lead-borate network interconnected through Pb-O-B and B-O-B bridges and the transformation of some tetrahedral [BO{sub 4}] units into trigonal [BO{sub 3}] units. Then, gadolinium ions have affinity towards [BO{sub 3}] structural units which contain non-bridging oxygens necessary for the charge compensation because the more electronegative [BO{sub 3}] structural units were implied in the formation of B-O-Gd bonds and the transformation of glass network into a glass ceramic. We propose a possible structural model of building blocks for the formation of continuous random 3B{sub 2}O{sub 3}.PbO network glass used by density functional theory (DFT) calculations. DFT calculations show that lead atoms occupy three different sites in the proposed model. The first is coordinated with six oxygen atoms forming distorted octahedral geometries. The second lead atom has an octahedral oxygen environment and the five longer Pb-O bonds are considered as participating in the metal coordination scheme. The third lead atom has ionic character. In agreement with the results offered by the experimental FTIR data, the theoretical IR data confirm that our proposed structure is highly possible.

  19. Explicit and implicit assessment of gender roles.

    PubMed

    Fernández, Juan; Quiroga, M Ángeles; Escorial, Sergio; Privado, Jesús

    2014-05-01

    Gender roles have been assessed by explicit measures and, recently, by implicit measures. In the former case, the theoretical assumptions have been questioned by empirical results. To solve this contradiction, we carried out two concatenated studies based on a relatively well-founded theoretical and empirical approach. The first study was designed to obtain a sample of genderized activities of the domestic sphere by means of an explicit assessment. Forty-two raters (22 women and 20 men, balanced on age, sex, and level of education) took part as raters. In the second study, an implicit assessment of gender roles was carried out, focusing on the response time given to the sample activities obtained from the first study. A total of 164 adults (90 women and 74 men, mean age = 43), with experience in living with a partner and balanced on age, sex, and level of education, participated. Taken together, results show that explicit and implicit assessment converge. The current social reality shows that there is still no equity in some gender roles in the domestic sphere. These consistent results show considerable theoretical and empirical robustness, due to the double implicit and explicit assessment.

  20. Gender interactions and success.

    PubMed

    Wiggins, Carla; Peterson, Teri

    2004-01-01

    Does gender by itself, or does gender's interaction with career variables, better explain the difference between women and men's careers in healthcare management? US healthcare managers were surveyed regarding career and personal experiences. Gender was statistically interacted with explanatory variables. Multiple regression with backwards selection systematically removed non-significant variables. All gender interaction variables were non-significant. Much of the literature proposes that work and career factors impact working women differently than working men. We find that while gender alone is a significant predictor of income, it does not significantly interact with other career variables.

  1. Glass strengthening and patterning methods

    SciTech Connect

    Harper, David C; Wereszczak, Andrew A; Duty, Chad E

    2015-01-27

    High intensity plasma-arc heat sources, such as a plasma-arc lamp, are used to irradiate glass, glass ceramics and/or ceramic materials to strengthen the glass. The same high intensity plasma-arc heat source may also be used to form a permanent pattern on the glass surface--the pattern being raised above the glass surface and integral with the glass (formed of the same material) by use of, for example, a screen-printed ink composition having been irradiated by the heat source.

  2. Glass formation - A contemporary view

    NASA Technical Reports Server (NTRS)

    Uhlmann, D. R.

    1983-01-01

    The process of glass formation is discussed from several perspectives. Particular attention is directed to kinetic treatments of glass formation and to the question of how fast a given liquid must be cooled in order to form a glass. Specific consideration is paid to the calculation of critical cooling rates for glass formation, to the effects of nucleating heterogeneities and transients in nucleation on the critical cooling rates, to crystallization on reheating a glass, to the experimental determination of nucleation rates and barriers to crystal nucleation, and to the characteristics of materials which are most conducive to glass formation.

  3. Lattice model of glasses

    NASA Astrophysics Data System (ADS)

    Cellai, Davide; Fima, Andrzej Z.; Lawlor, Aonghus; Dawson, Kenneth A.

    2011-03-01

    Glass-forming liquids have been extensively studied in recent decades, but there is still no theory that fully describes these systems, and the diversity of treatments is in itself a barrier to understanding. Here we introduce a new simple model that (possessing both liquid-crystal and glass transition) unifies different approaches, producing most of the phenomena associated with real glasses, without loss of the simplicity that theorists require. Within the model we calculate energy relaxation, nonexponential slowing phenomena, the Kauzmann temperature, and other classical signatures. Moreover, the model reproduces a subdiffusive exponent observed in experiments of dense systems. The simplicity of the model allows us to identify the microscopic origin of glassification, leaving open the possibility for theorists to make further progress.

  4. Lattice model of glasses.

    PubMed

    Cellai, Davide; Fima, Andrzej Z; Lawlor, Aonghus; Dawson, Kenneth A

    2011-03-21

    Glass-forming liquids have been extensively studied in recent decades, but there is still no theory that fully describes these systems, and the diversity of treatments is in itself a barrier to understanding. Here we introduce a new simple model that (possessing both liquid-crystal and glass transition) unifies different approaches, producing most of the phenomena associated with real glasses, without loss of the simplicity that theorists require. Within the model we calculate energy relaxation, nonexponential slowing phenomena, the Kauzmann temperature, and other classical signatures. Moreover, the model reproduces a subdiffusive exponent observed in experiments of dense systems. The simplicity of the model allows us to identify the microscopic origin of glassification, leaving open the possibility for theorists to make further progress.

  5. Waste glass melting stages

    SciTech Connect

    Anderson, L.D.; Dennis, T.; Elliott, M.L.; Hrma, P.

    1993-04-01

    Three different simulated nuclear waste glass feeds, consisting of dried waste and glass frit, were heat treated for 1 hour in a gradient furnace at temperatures ranging from approximately 600[degrees]C--1000[degrees]C. Simulated melter feeds from the Hanford Waste Vitrification Plant (HWVP), the Defense Waste Processing Facility (DWPF), and Kernforschungszentrum Karlsruhe (KfK) in Germany were used. The samples were thin-sectioned and examined by optical microscopy to investigate the stages of the conversion from feed to glass. Various phenomena were seen, such as frit softening, bubble formation, foaming, bubble motion and removal, convective mixing, and homogenization. Behavior of different feeds was similar, although the degree of gas generation and melt homogenization varied.

  6. Waste glass melting stages

    SciTech Connect

    Anderson, L.D.; Dennis, T.; Elliott, M.L.; Hrma, P.

    1993-04-01

    Three different simulated nuclear waste glass feeds, consisting of dried waste and glass frit, were heat treated for 1 hour in a gradient furnace at temperatures ranging from approximately 600{degrees}C--1000{degrees}C. Simulated melter feeds from the Hanford Waste Vitrification Plant (HWVP), the Defense Waste Processing Facility (DWPF), and Kernforschungszentrum Karlsruhe (KfK) in Germany were used. The samples were thin-sectioned and examined by optical microscopy to investigate the stages of the conversion from feed to glass. Various phenomena were seen, such as frit softening, bubble formation, foaming, bubble motion and removal, convective mixing, and homogenization. Behavior of different feeds was similar, although the degree of gas generation and melt homogenization varied.

  7. Physical Phenomena in Containerless Glass Processing

    NASA Technical Reports Server (NTRS)

    Subramanian, R. S.; Cole, R.

    1985-01-01

    An investigation into the various physical phenomena of importance in the space experiments is under way. Theoretical models of thermocapillary flow in drops, thermal migration of bubbles and droplets, the motion of bubbles inside drops, and the migration of bubbles in rotating liquid bodies are being developed. Experiments were conducted on the migration of bubbles and droplets to the axis of a rotating liquid body, and the rise of bubbles in molten glass. Also, experiments on thermocapillary motion in silicone oils as well as glass melts were performed. Experiments are currently being conducted on the migration of bubbles in a thermal gradient, and on their motion inside unconstrained liquid drops in a rotating liquid.

  8. Gender determination in populus

    SciTech Connect

    McLetchie, D.N.; Tuskan, G.A.

    1994-12-31

    Gender, the expression of maleness or femaleness, in dioecious plants has been associated with changes in morphology, physiology, ecological position, and commercial importance of several species, including members of the Salicaceae family. Various mechanisms have been proposed to explain the expression of gender in Salicaceae, including sex chromosomes, simple Mendelian genes, quantitative genes, environment, and genotype-by-environment interactions. Published reports would favor a genetic basis for gender. The objective of this study was to identify molecular markers associated with gender in a segregating family of hybrid poplars. Bulked segregant analysis and chi-squared analysis were used to test for the occurrence of sex chromosomes, individual loci, and chromosome ratios (i.e., ploidy levels) as the mechanisms for gender determination. Examination of 2488 PCR based RAPD markers from 1219 primers revealed nine polymorphic bands between male and female bulked samples. However, linkage analysis indicated that none of these markers were significantly associated with gender. Chisquared results for difference in male-to-female ratios between diploid and triploid genotypes also revealed no significant differences. These findings suggest gender is not controlled via sex chromosomes, simple Mendelian loci or ratios of autosome to gender-determining loci. It is possible that gender is determined genetically by regions of the genome not sampled by the tested markers or by a complex of loci operating in an additive threshold manner or in an epistatic manner. It is also possible that gender is determined environmentally at an early zygote stage, canalizing gender expression.

  9. Optical glasses and glass ceramics for large optical systems

    NASA Astrophysics Data System (ADS)

    Doehring, Thorsten; Hartmann, Peter; Morian, Hans F.; Jedamzik, Ralf

    2003-02-01

    Schott has delivered blanks for large lenses and prisms since many decades. Glass and glass ceramics objects with dimensions above 300 mm diameter or edge lengths will remain challenges for a glass manufacturer. This holds especially when the quality specifications exceed the standard level significantly. Optical glass blocks of more than half a ton have been produced with outstanding internal quality. Although the manufacturing process is well controlled there are restrictions on the availability of such objects (glass types, long process times e.g.). Implications of the glass production process are presented as a guideline for designers in order to avoid unnecessary time losses. The similarity of the production process of the glass ceramic ZERODUR to that of optical glasses results in high homogeneity with regard to the coefficient of thermal expansion as well as to the optical properties. This qualifies ZERODUR for even higher demanding applications especially when reproducibility in series production is required.

  10. Gender Stereotype Susceptibility

    PubMed Central

    Pavlova, Marina A.; Weber, Susanna; Simoes, Elisabeth; Sokolov, Alexander N.

    2014-01-01

    Gender affects performance on a variety of cognitive tasks, and this impact may stem from socio-cultural factors such as gender stereotyping. Here we systematically manipulated gender stereotype messages on a social cognition task on which no initial gender gap has been documented. The outcome reveals: (i) Stereotyping affects both females and males, with a more pronounced impact on females. Yet an explicit negative message for males elicits a striking paradoxical deterioration in performance of females. (ii) Irrespective of gender and directness of message, valence of stereotype message affects performance: negative messages have stronger influence than positive ones. (iii) Directness of stereotype message differentially impacts performance of females and males: females tend to be stronger affected by implicit than explicit negative messages, whereas in males this relationship is opposite. The data are discussed in the light of neural networks underlying gender stereotyping. The findings provide novel insights into the sources of gender related fluctuations in cognition and behavior. PMID:25517903

  11. Gender stereotype susceptibility.

    PubMed

    Pavlova, Marina A; Weber, Susanna; Simoes, Elisabeth; Sokolov, Alexander N

    2014-01-01

    Gender affects performance on a variety of cognitive tasks, and this impact may stem from socio-cultural factors such as gender stereotyping. Here we systematically manipulated gender stereotype messages on a social cognition task on which no initial gender gap has been documented. The outcome reveals: (i) Stereotyping affects both females and males, with a more pronounced impact on females. Yet an explicit negative message for males elicits a striking paradoxical deterioration in performance of females. (ii) Irrespective of gender and directness of message, valence of stereotype message affects performance: negative messages have stronger influence than positive ones. (iii) Directness of stereotype message differentially impacts performance of females and males: females tend to be stronger affected by implicit than explicit negative messages, whereas in males this relationship is opposite. The data are discussed in the light of neural networks underlying gender stereotyping. The findings provide novel insights into the sources of gender related fluctuations in cognition and behavior.

  12. Real space renormalization group theory of disordered models of glasses.

    PubMed

    Angelini, Maria Chiara; Biroli, Giulio

    2017-03-28

    We develop a real space renormalization group analysis of disordered models of glasses, in particular of the spin models at the origin of the random first-order transition theory. We find three fixed points, respectively, associated with the liquid state, with the critical behavior, and with the glass state. The latter two are zero-temperature ones; this provides a natural explanation of the growth of effective activation energy scale and the concomitant huge increase of relaxation time approaching the glass transition. The lower critical dimension depends on the nature of the interacting degrees of freedom and is higher than three for all models. This does not prevent 3D systems from being glassy. Indeed, we find that their renormalization group flow is affected by the fixed points existing in higher dimension and in consequence is nontrivial. Within our theoretical framework, the glass transition results in an avoided phase transition.

  13. FTIR of binary lead borate glass: Structural investigation

    NASA Astrophysics Data System (ADS)

    Othman, H. A.; Elkholy, H. S.; Hager, I. Z.

    2016-02-01

    The glass samples were prepared according to the following formula: (100-x) B2O3 - x PbO, where x = 20-80 mol% by melt quenching method. The density of the prepared samples was measured and molar volume was calculated. IR spectra were measured for the prepared samples to investigate the glass structure. The IR spectra were deconvoluted using curves of Gaussian shape at approximately the same frequencies. The deconvoluted data were used to study the effect of PbO content on all the structural borate groups. Some structural parameters such as density, packing density, bond length and bond force constant were theoretically calculated and were compared to the obtained experimental results. Deviation between the experimental and theoretically calculated parameters reflects the dual role of PbO content on the network of borate glass.

  14. Crystallization of fluorozirconate glasses

    NASA Technical Reports Server (NTRS)

    Bansal, Narottam P.; Doremus, Robert H.; Bruce, A. J.; Moynihan, C. T.

    1984-01-01

    The crystallization of a number of glasses of the fluorozirconate family has been studied (using powder X-ray diffraction and DSC) as a function of time and temperature of heating. The main crystalline phases were beta BaZrF6 and beta BaZr2F10. Stable and metastble transformations to the low-temperature alpha phases were also investigated. The size of crystallites in fully devitrified glasses was calculated (from line broadening of the X-ray diffraction peaks) to be about 60 nm.

  15. Transient nucleation in glasses

    NASA Technical Reports Server (NTRS)

    Kelton, K. F.

    1991-01-01

    Nucleation rates in condensed systems are frequently not at their steady state values. Such time dependent (or transient) nucleation is most clearly observed in devitrification studies of metallic and silicate glasses. The origin of transient nucleation and its role in the formation and stability of desired phases and microstructures are discussed. Numerical models of nucleation in isothermal and nonisothermal situations, based on the coupled differential equations describing cluster evolution within the classical theory, are presented. The importance of transient nucleation in glass formation and crystallization is discussed.

  16. Training Guidelines: Hand Blowing, Pressing, & Shaping of Glass.

    ERIC Educational Resources Information Center

    Ceramics, Glass, and Mineral Products Industry Training Board, Harrow (England).

    This manual of training guidelines describes the procedure for personnel intake and traces the training process which a worker must go through to become a glass craftsman. A number of charts present the skills and items of knowledge which the individual craftsman must master. Examples are included of theoretical and practical test items to certify…

  17. Characterizing glass frits for slurries

    NASA Technical Reports Server (NTRS)

    Nakano, H. N.

    1979-01-01

    Glass frit can be mixed with consistently reproducible properties even from different batches of glass frit using technique to measure one quantity that determines integrated properties of frit for combination with given liquid.

  18. Containerless processing of fluoride glass

    NASA Technical Reports Server (NTRS)

    Doremus, Robert H.

    1990-01-01

    Ground-based experiments on glass formation, crystallization, surface tension, vaporization, and chemical durability of a zirconium-barium-lanthanum (ZBL) fluoride glass are summarized. In a container large, columnar grains grew out from the container-glass interface during cooling. The main crystalline phase was alpha BaZrF6. A ZBL glass sphere was levitated acoustically during Shuttle flight STS-11. The glass was melted and then cooled while being levitated (containerless). Crystallization in the recovered sample was very fine and mainly beta BaZr2F10, showing the influence of the container on the nucleation and microstructure of crystallization in the glass. Glass formation should be easier for a containerless glass than in a container.

  19. Containerless processing of fluoride glass

    NASA Technical Reports Server (NTRS)

    Doremus, Robert H.

    1990-01-01

    Ground-based experiments on glass formation, crystallization, surface tension, vaporization, and chemical durability of a zirconium-barium-lanthanum (ZBL) fluoride glass are summarized. In a container large, columnar grains grew out from the container-glass interface during cooling. The main crystalline phase was alpha BaZrF6. A ZBL glass sphere was levitated acoustically during Shuttle flight STS-11. The glass was melted and then cooled while being levitated (containerless). Crystallization in the recovered sample was very fine and mainly beta BaZr2F10, showing the influence of the container on the nucleation and microstructure of crystallization in the glass. Glass formation should be easier for a containerless glass than in a container.

  20. Barstow heliostat mirror glass characterization

    NASA Astrophysics Data System (ADS)

    Lind, M. A.; Buckwalter, C. Q.

    1980-09-01

    The technical analysis performed on the special run of low iron float glass for a ten megawatt solar thermal/electric pilot power plant is discussed. The topics that are addressed include the optical properties and the relative durability of the glass. Two optical parameters, solar transmittance and optical flatness, were measured as referenced in the specification and found to be better than the stated tolerances. The average solar transmittance exceeded 0.890 transmittance units. The glass also exhibited optical angular flatness deviations less than + or - 1.0 mrad as required. Both qualitative and quantitative accelerated weathering tests were performed on the glass in order to compare its durability to other soda lime float glass and alternate composition glasses of interest to the solar community. In both the quantitative leaching experiments and the more qualitative room temperature and elevated temperature water vapor exposure experiments the heliostat glass exhibited the same characteristics as the other soda lime silicate float glasses.

  1. Making Highly Pure Glass Rods

    NASA Technical Reports Server (NTRS)

    Naumann, R. J.

    1986-01-01

    Proposed quasi-containerless method for making glass rods or fibers minimizes contact between processing equipment and product. Method allows greater range of product sizes and shapes than achieved in experiments on containerless processing. Molten zone established in polycrystalline rod. Furnace sections separated, and glass rod solidifies between them. Clamp supports solid glass as it grows in length. Pulling clamp rapidly away from melt draws glass fiber. Fiber diameter controlled by adjustment of pulling rate.

  2. Glass and ceramics. [lunar resources

    NASA Technical Reports Server (NTRS)

    Haskin, Larry A.

    1992-01-01

    A variety of glasses and ceramics can be produced from bulk lunar materials or from separated components. Glassy products include sintered regolith, quenched molten basalt, and transparent glass formed from fused plagioclase. No research has been carried out on lunar material or close simulants, so properties are not known in detail; however, common glass technologies such as molding and spinning seem feasible. Possible methods for producing glass and ceramic materials are discussed along with some potential uses of the resulting products.

  3. What Glass Ceiling?

    ERIC Educational Resources Information Center

    Lynch, Michael; Post, Katherine

    1996-01-01

    A recent study drawing on data from the Census Bureau and the Bureau of Labor Statistics suggests that the wage gap between men and women has virtually disappeared, and that the so-called "glass ceiling" results more from age and qualifications than from explicit discrimination. (SLD)

  4. Triad ''Metal - Enamel - Glass''

    NASA Astrophysics Data System (ADS)

    Mukhina, T.; Petrova, S.; Toporova, V.; Fedyaeva, T.

    2014-10-01

    This article shows how to change the color of metal and glass. Both these materials are self-sufficient, but sometimes used together. For example, enameling. In this case, the adhesion between metal substrate and stekloobraznae enamel layer, which was conducted on a stretching and a bend, was tested.

  5. "Stained Glass" Landscape Windows

    ERIC Educational Resources Information Center

    Vannata, Janine

    2008-01-01

    Both adults and children alike marvel at the grand vivid stained-glass windows created by American artist Louis Comfort Tiffany. Today he is commonly recognized as one of America's most influential designers and artists throughout the last nineteenth and early twentieth century. In the lesson described in this article, students created their own…

  6. Glass ceilings of professionalisation.

    PubMed

    Stott, Dawn L

    2016-04-01

    The term glass ceiling is a political term often used to describe an unbreakable barrier that isnot visible with the human eye, but it keeps minorities from rising up i.e. it is a barrier to minoritygroups, in the past (and sometimes still) for women, that stops them from achieving theirtrue potential.

  7. "Stained Glass" Landscape Windows

    ERIC Educational Resources Information Center

    Vannata, Janine

    2008-01-01

    Both adults and children alike marvel at the grand vivid stained-glass windows created by American artist Louis Comfort Tiffany. Today he is commonly recognized as one of America's most influential designers and artists throughout the last nineteenth and early twentieth century. In the lesson described in this article, students created their own…

  8. Shimmering Stained Glass.

    ERIC Educational Resources Information Center

    Simon, Gail Murray

    1998-01-01

    Presents an art lesson for fifth- and sixth-graders where they create a translucent design of colored cellophane on black paper inspired by the stained-glass windows of the Middle Ages and the artwork of Lewis Comfort Tiffany. Enables the students to become crafts people rather than just observers of the past. (CMK)

  9. CADMIUM PHOSPHATE GLASS

    DOEpatents

    Carpenter, H.W.; Johnson, P.D.

    1963-04-01

    A method of preparing a cadmium phosphate glass that comprises providing a mixture of solid inorganic compounds of cadmuim and phosphate having vaporizable components and heating the resulting composition to a temperature of at least 850 un. Concent 85% C is presented. (AEC)

  10. Stained-Glass Pastels

    ERIC Educational Resources Information Center

    Laird, Shirley

    2009-01-01

    The author has always liked the look of stained-glass windows. Usually the designs are simplified and the shapes are easier for younger students to draw. This technique seemed to be the perfect place for her fifth-graders to try their hand at color mixing. The smaller spaces and simple shapes were just what she needed for this group. Her students…

  11. Yesterday's Trash Makes Tomorrow's "Glass"

    ERIC Educational Resources Information Center

    Wayne, Dale

    2010-01-01

    In this article, the author describes a glass art project inspired by Dale Chihuly. This project uses two-liter plastic soda bottles which are cut apart and trimmed. Applying heat using a hair dryer, the plastic curls and takes an uneven blown-glass quality. The "glass" is then painted using acrylic paint. (Contains 2 resources and 1 online…

  12. Keratopathy associated with intracorneal glass

    SciTech Connect

    Mannis, M.J.; Fiori, C.E.; Krachmer, J.H.; Rodrigues, M.M.; Pardos, G.

    1981-05-01

    A progressive nonedematous keratopathy developed in a 36-year-old patient after she was struck in the eye by glass fragments. Biopsy material that was examined by electron microscopy and electron beam microanalysis demonstrated the presence of intracorneal glass fragments, which could not be detected clinically. Retained intracorneal glass, generally thought to be completely inert, can be associated with a chronic keratopathy.

  13. Barstow heliostat mirror glass characterization

    SciTech Connect

    Lind, M.A.; Buckwalter, C.Q.

    1980-09-01

    The technical analysis performed on the special run of low iron float glass procured from the Ford Glass Division for the ten megawatt solar thermal/electric pilot power plant to be constructed at Barstow, California is discussed. The topics that are addressed include the optical properties and the relative durability of the glass. Two optical parameters, solar transmittance and optical flatness, were measured as referenced in the specification and found to be better than the stated tolerances. The average solar transmittance exceeded 0.890 transmittance units. The glass also exhibited optical angular flatness deviations less than +-1.0 mrad as required. Both qualitative and quantitative accelerated weathering tests were performed on the glass in order to compare its durability to other soda lime float glass and alternate composition glasses of interest to the solar community. In both the quantitative leaching experiments and the more qualitative room temperature and elevated temperature water vapor exposure experiments the heliostat glass exhibited the same characteristics as the other soda-lime silicate float glasses. As a final test for mirroring compatability, selected samples of the production run of the glass were sent to four different commercial manufacturers for mirror coating. None of the manufacturers reported any difficulty silvering the glass. Based on the tests performed, the glass meets or exceeds all optical specifications for the Barstow heliostat field.

  14. Yesterday's Trash Makes Tomorrow's "Glass"

    ERIC Educational Resources Information Center

    Wayne, Dale

    2010-01-01

    In this article, the author describes a glass art project inspired by Dale Chihuly. This project uses two-liter plastic soda bottles which are cut apart and trimmed. Applying heat using a hair dryer, the plastic curls and takes an uneven blown-glass quality. The "glass" is then painted using acrylic paint. (Contains 2 resources and 1 online…

  15. Electronic hybridisation implications for the damage-tolerance of thin film metallic glasses

    NASA Astrophysics Data System (ADS)

    Schnabel, Volker; Jaya, B. Nagamani; Köhler, Mathias; Music, Denis; Kirchlechner, Christoph; Dehm, Gerhard; Raabe, Dierk; Schneider, Jochen M.

    2016-11-01

    A paramount challenge in materials science is to design damage-tolerant glasses. Poisson’s ratio is commonly used as a criterion to gauge the brittle-ductile transition in glasses. However, our data, as well as results in the literature, are in conflict with the concept of Poisson’s ratio serving as a universal parameter for fracture energy. Here, we identify the electronic structure fingerprint associated with damage tolerance in thin film metallic glasses. Our correlative theoretical and experimental data reveal that the fraction of bonds stemming from hybridised states compared to the overall bonding can be associated with damage tolerance in thin film metallic glasses.

  16. Electronic hybridisation implications for the damage-tolerance of thin film metallic glasses

    PubMed Central

    Schnabel, Volker; Jaya, B. Nagamani; Köhler, Mathias; Music, Denis; Kirchlechner, Christoph; Dehm, Gerhard; Raabe, Dierk; Schneider, Jochen M.

    2016-01-01

    A paramount challenge in materials science is to design damage-tolerant glasses. Poisson’s ratio is commonly used as a criterion to gauge the brittle-ductile transition in glasses. However, our data, as well as results in the literature, are in conflict with the concept of Poisson’s ratio serving as a universal parameter for fracture energy. Here, we identify the electronic structure fingerprint associated with damage tolerance in thin film metallic glasses. Our correlative theoretical and experimental data reveal that the fraction of bonds stemming from hybridised states compared to the overall bonding can be associated with damage tolerance in thin film metallic glasses. PMID:27819318

  17. Electronic hybridisation implications for the damage-tolerance of thin film metallic glasses.

    PubMed

    Schnabel, Volker; Jaya, B Nagamani; Köhler, Mathias; Music, Denis; Kirchlechner, Christoph; Dehm, Gerhard; Raabe, Dierk; Schneider, Jochen M

    2016-11-07

    A paramount challenge in materials science is to design damage-tolerant glasses. Poisson's ratio is commonly used as a criterion to gauge the brittle-ductile transition in glasses. However, our data, as well as results in the literature, are in conflict with the concept of Poisson's ratio serving as a universal parameter for fracture energy. Here, we identify the electronic structure fingerprint associated with damage tolerance in thin film metallic glasses. Our correlative theoretical and experimental data reveal that the fraction of bonds stemming from hybridised states compared to the overall bonding can be associated with damage tolerance in thin film metallic glasses.

  18. Water's second glass transition.

    PubMed

    Amann-Winkel, Katrin; Gainaru, Catalin; Handle, Philip H; Seidl, Markus; Nelson, Helge; Böhmer, Roland; Loerting, Thomas

    2013-10-29

    The glassy states of water are of common interest as the majority of H2O in space is in the glassy state and especially because a proper description of this phenomenon is considered to be the key to our understanding why liquid water shows exceptional properties, different from all other liquids. The occurrence of water's calorimetric glass transition of low-density amorphous ice at 136 K has been discussed controversially for many years because its calorimetric signature is very feeble. Here, we report that high-density amorphous ice at ambient pressure shows a distinct calorimetric glass transitions at 116 K and present evidence that this second glass transition involves liquid-like translational mobility of water molecules. This "double Tg scenario" is related to the coexistence of two liquid phases. The calorimetric signature of the second glass transition is much less feeble, with a heat capacity increase at Tg,2 about five times as large as at Tg,1. By using broadband-dielectric spectroscopy we resolve loss peaks yielding relaxation times near 100 s at 126 K for low-density amorphous ice and at 110 K for high-density amorphous ice as signatures of these two distinct glass transitions. Temperature-dependent dielectric data and heating-rate-dependent calorimetric data allow us to construct the relaxation map for the two distinct phases of water and to extract fragility indices m = 14 for the low-density and m = 20-25 for the high-density liquid. Thus, low-density liquid is classified as the strongest of all liquids known ("superstrong"), and also high-density liquid is classified as a strong liquid.

  19. [The gender gap in Italian medicine].

    PubMed

    De Simone, Silvia; Podda, Daiana; Lampis, Jessica

    2015-01-28

    This study is collocated in the debate about the gender gap in Medicine giving voice to female physicians who have damaged the "glass ceiling". Our research offers a contribute to the exploration about the motivations of persistence of gender gap in Medicine despite current changes. This study is based on 21 biographical interviews to female physicians who are managers in Italian hospitals. The themes emerged by data analysis concerned the participants 'discrimination experiences in their hierarchical advancement, the evidences of a persistence of horizontal segregation in some medical specializations, the difficult to find a work-life balance and the effects of this difficult on the female physicians' health. Our research confirmed a persistence of gender gap in the medical world, which disadvantages women in their career choices and in their hierarchical advancement and which appears in the form of invisible barriers impregnated of stereotypes and prejudices that are taken for granted by many men and women, especially those who have the power; these barriers make the female doctors 'health more vulnerable to the event of work-related stress. By the dates emerged the necessity of cultural and institutional interventions, actions for deconstruction of gender stereotypes, and the necessity of intervention for a more flexible and functioning work organization that satisfies the female physicians' needs.

  20. Gender similarities and differences.

    PubMed

    Hyde, Janet Shibley

    2014-01-01

    Whether men and women are fundamentally different or similar has been debated for more than a century. This review summarizes major theories designed to explain gender differences: evolutionary theories, cognitive social learning theory, sociocultural theory, and expectancy-value theory. The gender similarities hypothesis raises the possibility of theorizing gender similarities. Statistical methods for the analysis of gender differences and similarities are reviewed, including effect sizes, meta-analysis, taxometric analysis, and equivalence testing. Then, relying mainly on evidence from meta-analyses, gender differences are reviewed in cognitive performance (e.g., math performance), personality and social behaviors (e.g., temperament, emotions, aggression, and leadership), and psychological well-being. The evidence on gender differences in variance is summarized. The final sections explore applications of intersectionality and directions for future research.

  1. Volcanic glass as a natural analog for borosilicate waste glass

    SciTech Connect

    Morgenstein, M.E.; Shettel, D.L.

    1994-12-31

    Obsidian and basaltic glass are opposite end-members of natural volcanic glass compositions. Syngenetic and diagenetic tensile failure in basaltic glass (low silica glass) is pervasive and provides abundant alteration fronts deep into the glass structure. Perlitic fracturing in obsidian (high silica glass) limits the alteration zones to an {open_quotes}onion skin{close_quotes} geometry. Borosilicate waste glass behaves similarly to the natural analog of basaltic glass (sideromelane). During geologic time, established and tensile fracture networks form glass cells (a three-dimensional reticulated pattern) where the production of new fracture surfaces increases through time by geometric progression. This suggests that borosilicate glass monoliths will eventually become rubble. Rates of reaction appear to double for every 12C{degrees} of temperature increase. Published leach rates suggest that the entire inventory of certain radionuclides may be released during the 10,000 year regulatory time period. Steam alteration prior to liquid attack combined with pervasive deep tensile failure behavior may suggest that the glass waste form is not license defensible without a metallic- and/or ceramic-type composite barrier as an overpack.

  2. Potential utilization of glass experiments in space

    NASA Technical Reports Server (NTRS)

    Kreidl, N. J.

    1984-01-01

    Materials processing in space utilizing the microgravity environment is discussed; glass processing in particular is considered. Attention is given to the processing of glass shells, critical cooling rate and novel glasses, gel synthesis of glasses, immiscibility, surface tension, and glass composites. Soviet glass experiments in space are also enumerated.

  3. Social dominance orientation and gender: the moderating role of gender identity.

    PubMed

    Wilson, Marc Stewart; Liu, James H

    2003-06-01

    The aim of this research was to investigate the claim that gender differences in levels of social dominance orientation (SDO; Pratto, Sidanius, Stallworth, & Malle, 1994), a personality variable measuring a general predisposition towards anti-egalitarianism, are essentially invariant (Sidanius & Pratto, 1999). Previous findings have indicated that (regardless of covariate) males display higher levels of SDO than females. Two studies were conducted to test the expectation (derived from social identity theory) that the gender-SDO relationship would be moderated by strength of gender group identification. Both samples (150 non-students and 163 students) completed the full SDO(6) measure, and measures of gender group identification. Consistent with predictions, strength of gender identification was found to moderate the gender-SDO relationship, such that increasing group identification was associated with increasing SDO scores for males, and decreasing SDO for females. This result raises questions concerning the theoretical basis of social dominance theory, and whether gender group membership should be accorded a different status from other 'arbitrary-set' group memberships.

  4. Apollo 12 ropy glasses revisited

    NASA Technical Reports Server (NTRS)

    Wentworth, S. J.; Mckay, D. S.; Lindstrom, D. J.; Basu, A.; Martinez, R. R.; Bogard, D. D.; Garrison, D. H.

    1994-01-01

    We analyzed ropy glasses from Apollo 12 soils 12032 and 12033 by a variety of techniques including SEM/EDX, electron microprobe analysis, INAA, and Ar-39-Ar-40 age dating. The ropy glasses have potassium rare earth elements phosphorous (KREEP)-like compositions different from those of local Apollo 12 mare soils; it is likely that the ropy glasses are of exotic origin. Mixing calculations indicate that the ropy glasses formed from a liquid enriched in KREEP and that the ropy glass liquid also contained a significant amount of mare material. The presence of solar Ar and a trace of regolith-derived glass within the ropy glasses are evidence that the ropy glasses contain a small regolith component. Anorthosite and crystalline breccia (KREEP) clasts occur in some ropy glasses. We also found within these glasses clasts of felsite (fine-grained granitic fragments) very similar in texture and composition to the larger Apollo 12 felsites, which have a Ar-39-Ar-40 degassing age of 800 +/- 15 Ma. Measurements of 39-Ar-40-Ar in 12032 ropy glass indicate that it was degassed at the same time as the large felsite although the ropy glass was not completely degassed. The ropy glasses and felsites, therefore, probably came from the same source. Most early investigators suggested that the Apollo 12 ropy glasses were part of the ejecta deposited at the Apollo 12 site from the Copernicus impact. Our new data reinforce this model. If these ropy glasses are from Copernicus, they provide new clues to the nature of the target material at the Copernicus site, a part of the Moon that has not been sampled directly.

  5. The gender similarities hypothesis.

    PubMed

    Hyde, Janet Shibley

    2005-09-01

    The differences model, which argues that males and females are vastly different psychologically, dominates the popular media. Here, the author advances a very different view, the gender similarities hypothesis, which holds that males and females are similar on most, but not all, psychological variables. Results from a review of 46 meta-analyses support the gender similarities hypothesis. Gender differences can vary substantially in magnitude at different ages and depend on the context in which measurement occurs. Overinflated claims of gender differences carry substantial costs in areas such as the workplace and relationships.

  6. Class and Gender

    ERIC Educational Resources Information Center

    Hart, Mechthild

    2005-01-01

    Everyone is dependent on caring labor. Because women's labor is financially beneficial to global capitalism, gender is inseparable from class, regardless of the specific national or cultural contexts.

  7. Controversies in Gender Diagnoses.

    PubMed

    Drescher, Jack

    2014-03-01

    This article presents the author's thoughts on gender diagnosis controversies during his tenure at the DSM-5 Workgroup on Sexual and Gender Identity Disorders and the ICD-11 Working Group on the Classification of Sexual Disorders and Sexual Health. The work summarizes some of the published conclusions of the DSM-5 and ICD-11 revision processes regarding three particular controversies: (1) stigma versus access to care; (2) the retention of a child gender diagnosis; and (3) the treatment of prepubescent transgender children. Both the DSM and ICD work groups decided that despite the stigma associated with a diagnosis, retaining an adolescent and adult gender diagnosis is necessary to maintain access to care. As for the child gender diagnosis, given the heterogeneity of this clinical population and that gender dysphoria does not persist in most children, a child diagnosis of Gender Dysphoria (DSM) and Gender Incongruence (ICD) should be retained to facilitate ongoing evaluation and management in childhood while acknowledging the uncertainty of the outcome. The treatment of extremely gender variant prepubescent children remains a controversial subject since some underlying assumptions of the treating clinicians are a matter of opinion rather than of empirical data.

  8. How sex became gender.

    PubMed

    Nye, Robert A

    2010-01-01

    This article argues that "sex" which had been commonly assumed in the West to refer to a permanent set of biological and behavioural traits particular to men and women, is gradually being replaced in general usage by "gender." Though feminist theorists attempted to attach a constructivist meaning to gender, a generation of developmental theorists, clinicians and analysts has imbued the term with the determinism and biological qualities formerly ascribed to "sex." The triumph of this materialist conception of gender is not assured, but it threatens our ability to think about gender identity as a historically-constructed category.

  9. From Gender Bias to Gender Awareness in Medical Education

    ERIC Educational Resources Information Center

    Verdonk, Petra; Benschop, Yvonne W. M.; de Haes, Hanneke C. J. M.; Lagro-Janssen, Toine L. M.

    2009-01-01

    Gender is an essential determinant of health and illness. Gender awareness in doctors contributes to equity and equality in health and aims towards better health for men and women. Nevertheless, gender has largely been ignored in medicine. First, it is stated that medicine was "gender blind" by not considering gender whenever relevant. Secondly,…

  10. From Gender Bias to Gender Awareness in Medical Education

    ERIC Educational Resources Information Center

    Verdonk, Petra; Benschop, Yvonne W. M.; de Haes, Hanneke C. J. M.; Lagro-Janssen, Toine L. M.

    2009-01-01

    Gender is an essential determinant of health and illness. Gender awareness in doctors contributes to equity and equality in health and aims towards better health for men and women. Nevertheless, gender has largely been ignored in medicine. First, it is stated that medicine was "gender blind" by not considering gender whenever relevant. Secondly,…

  11. Profiles in garbage glass containers

    SciTech Connect

    Miller, C.

    1997-09-01

    Glass containers are made from sand, limestone, soda ash, cullet (crushed bottles), and various additives, including those used to color brown, green, or blue bottles. Sixty percent of the glass used in the US is clear (flint) and one-fourth is brown (amber). Almost half of the green bottles are imported wind and beer bottles. Other glass products include flat glass such as windows; fiberglass insulation; and glassware. These products use different manufacturing processes and different additives than container glass. This profile covers only container glass. Glass bottles are commonly collected in curb-side programs. Losses due to breakage and the abrasiveness of glass during collection and processing offset their low collection and processing costs. Breakage solutions include installation of interior baffles or nets in the collection trucks, special glass-only truck compartments, and limiting the number of times glass is transferred after collection before final processing. Ten states require deposits on glass bottles for beer and soft drinks and related items.

  12. Copper blue in an ancient glass bead: a XANES study

    NASA Astrophysics Data System (ADS)

    Veiga, J. P.; Figueiredo, M. O.

    2006-06-01

    The blue colour in ancient soda-lime glasses has been attributed to the presence of copper and/or cobalt but the origin of different shades is not yet fully interpreted. As a contribution to this question, a non-destructive X-ray absorption study at [ Cu]K-edge was undertaken on the blue (turquoise) layer from a “Nueva Cadiz” type tubular glass bead dated pre-XVII century where copper is the unique colouring agent. Minerals configuring two distinct blue tonalities due to Cu (2+) in similar square coordination were selected as basic model compounds: azurite, which is a classical navy-blue pigment used in ancient wall paintings over plaster, and chalcanthite, displaying exactly the same turquoise-blue tonality of tubular glass beads manufactured since the Egyptian Antiquity. Theoretical modelling of the XAFS spectra was undertaken using the FEFF code. The IFEFFIT software package was used for fitting the calculated spectra to experimental data. EXAFS results are discussed in view of the crystal structures of copper minerals chosen to model the speciation state and structural situation of that element prevailing in the turquoise-blue archaeological glass. Special attention is focused on the difficulties in theoretical modelling [ Cu]K-XANES spectra of ancient glasses with different colourings.

  13. Fluoride glass: Crystallization, surface tension

    NASA Technical Reports Server (NTRS)

    Doremus, R. H.

    1988-01-01

    Fluoride glass was levitated acoustically in the ACES apparatus on STS-11, and the recovered sample had a different microstructure from samples cooled in a container. Further experiments on levitated samples of fluoride glass are proposed. These include nucleation, crystallization, melting observations, measurement of surface tension of molten glass, and observation of bubbles in the glass. Ground experiments are required on sample preparation, outgassing, and surface reactions. The results should help in the development and evaluation of containerless processing, especially of glass, in the development of a contaminent-free method of measuring surface tensions of melts, in extending knowledge of gas and bubble behavior in fluoride glasses, and in increasing insight into the processing and properties of fluoride glasses.

  14. Production of glass or glass-ceramic to metal seals with the application of pressure

    DOEpatents

    Kelly, Michael D.; Kramer, Daniel P.

    1987-11-10

    In a process for preparing a glass or glass-ceramic to metal seal comprising contacting the glass with the metal and heat-treating the glass and metal under conditions whereby the glass to metal seal is effected and, optionally, the glass is converted to a glass-ceramic, an improvement comprises carrying out the heat-treating step using hot isostatic pressing.

  15. Production of glass or glass-ceramic to metal seals with the application of pressure

    DOEpatents

    Kelly, M.D.; Kramer, D.P.

    1985-01-04

    In a process for preparing a glass or glass-ceramic to metal seal comprising contacting the glass with the metal and heat-treating the glass and metal under conditions whereby the glass to metal seal is effected and, optionally, the glass is converted to a glass-ceramic, an improvement comprises carrying out the heat-treating step using hot isostatic pressing.

  16. Breaking the glass ceiling.

    PubMed

    Lazarus, A

    1997-03-01

    The glass ceiling is a form of organizational bias and discrimination that prevents qualified professionals from achieving positions of top governance and leadership. This article examines glass ceiling barriers that keep physicians from the upper reaches of management. While these factors apply mainly to women and minority physicians in academia, and are attributable to sexual harassment and discrimination, physicians as a class are frequently denied executive management positions. Such denial results from inadequate preparation for a career in health care administration. Important issues in the professional development of physician executives include mentoring, training and education, administrative experience, and cultural and personality factors. All of those must be considered when making the transition from medicine to management.

  17. Gravity Effects on Combustion Synthesis of Glasses

    NASA Technical Reports Server (NTRS)

    Yi, H. C.; Guigne, J. Y.; Moore, J. J.; Robinson, L. A.; Manerbino, A. R.; Schowengerdt, F. D.; Gokoglu, S. (Technical Monitor)

    2000-01-01

    The Combustion Synthesis technique has been used to produce glasses based on B2O3-Al2O3-MgO and CaO-Al2O3. The combustion characteristics of these combustion synthesis reactions using both small cylindrical pellets (SCP) and large spherical pellets (LSP) are presented. Low density pellets (approx. 35% of their theoretical density) were used, which made synthesis of low exothermic combustion reactions possible. Microstructural analysis of reacted samples was carried out to identify the glass-forming compositions. The effects of gravity on the glass formation were studied aboard the KC-135 using SCP samples. Gravity seemed to have such obvious effects on the combustion characteristics that the wave velocity was lower and the Width of the combustion wave was larger under reduced gravity conditions. Samples produced under low gravity also had more enhanced vitrification than those on ground, while some systems also exhibited lower combustion temperatures. It was also found that the container significantly affects both the combustion characteristics and microstructure. Substantially more divitrification occurred at the area which was in contact with the support (container).

  18. Excess Vibrational Modes in Model Glasses

    NASA Astrophysics Data System (ADS)

    Xu, Ning; Wyart, Matthieu; Liu, Andrea; Nagel, Sidney

    2007-03-01

    We performed both theoretical analysis and computer simulations to study the excess low-frequency normal modes (boson peak) for two widely-used model glasses at zero temperature. The onset frequencies for the anomalous modes from the simulations agree very well with predictions from variational calculations based on minimizing the vibrational energy cost of the lowest-frequency anomalous mode. This energy cost originates from the excess interactions per particle over zc, where zc=2d is the minimum number required for mechanical stability in d dimensions. The total z interactions per particle are divided into two classes: z1 ``stiff'' interactions determine the structure of the anomalous mode by adding extra nodes; the remaining z-z1 interactions act as a perturbation and increase the vibrational energy of the mode by increasing the restoring force for displacements. Even though both glasses studied have a high number of interactions per particle, (z1-zc)/zc is always smaller than 0.6, which indicates that the physics of jamming is relevant to the study of the excess normal modes in glasses.

  19. Fluctuations in the Dynamics of Glasses

    SciTech Connect

    Castillo, Horacio E.

    2015-05-06

    This research program addressed the question of the presence of dynamical heterogeneities – strong spatial fluctuations in the dynamics – in glass forming liquids and jamming systems near dynamical arrest, with particular emphasis on aging systems, i.e. systems that are in the (non-equilibrium) glass regime. The main goals proposed for this research were: to perform numerical simulations of atomistic structural glass models to characterize dynamical heterogeneities in out of equilibrium (aging) glassy systems; to test the hypothesis that a certain symmetry (“time reparametrization symmetry”) is present in microscopic models of glassy systems and that this symmetry can explain the main features of dynamical heterogeneities; and to test to what extent these phenomena are universal across different glassy/jamming systems. It was found that: most of the important features of dynamical heterogeneities in the aging regime could be described in terms of simple scaling behaviors; that some of the most basic theoretical models of glassy systems indeed have time reparametrization symmetry; that all tests performed in numerical simulation data were consistent with the predictions from time reparametrization symmetry; and that to a large degree, the main features of dynamical heterogeneities were universal across different glassy systems. Most of the findings that came out of this research have been reported in detail in eight papers in high quality journals, two unpublished but publicly accessible manuscripts, and 27 invited and contributed talks.

  20. Lead-silicate glass optical microbubble resonator

    SciTech Connect

    Wang, Pengfei; Ward, Jonathan; Yang, Yong; Chormaic, Síle Nic; Feng, Xian; Brambilla, Gilberto; Farrell, Gerald

    2015-02-09

    Microbubble whispering gallery resonators have the potential to become key components in a variety of active and passive photonic circuit devices by offering a range of significant functionalities. Here, we report on the fabrication, optical characterization, and theoretical analysis of lead-silicate glass and optical microbubble resonators. Evanescent field coupling to the microbubbles was achieved using a 1 μm diameter, silica microfiber at a wavelength of circa 775 nm. High Q-factor modes were efficiently excited in both single-stem and two-stem, lead-silicate glass, and microbubble resonators, with bubble diameters of 38 μm (single-stem) and 48 μm (two-stem). Whispering gallery mode resonances with Q-factors as high as 2.3 × 10{sup 5} (single-stem) and 7 × 10{sup 6} (two-stem) were observed. By exploiting the high-nonlinearity of the lead-silicate glass, this work will act as a catalyst for studying a range of nonlinear optical effects in microbubbles, such as Raman scattering and four-wave mixing, at low optical powers.

  1. Gel Precursors as Glass and Ceramic Starting Materials for Space Processing Applications Research

    NASA Technical Reports Server (NTRS)

    Downs, R. L.; Miller, W. J.

    1985-01-01

    The crystallization kinetics and glass forming ability of reluctant glass formers is investigated. This could ultimately aid the formation of bulk samples of unique glass compositions outside of normal glass forming regions allowing the optimization of certain properties of the glass. One important aspect of processing in space is the containerless undercooling of molten substances. Theoretically, the extent of undercooling can be greatly enhanced by solidifying in the absence of heterogeneous nucleation resulting from contact with crucibles or molds. Techniques were established for the measurement of crystallization kinetics and critical cooling rates. The glass formation ability and crystallization kinetics of Ga2O-43CaO and several Al2O3-CaO compositions were measured. An apparatus was set up to measure the temperature of spherical samples on a thermocouple at large cooling rates. The time and temperature of nucleation is recorded and the probability of nucleation at various cooling rates can be measured.

  2. Bulk Formation of Metallic Glasses and Amorphous Silicon from the Melt

    NASA Technical Reports Server (NTRS)

    Spaepen, F.

    1985-01-01

    By using metallic glass compositions with a high relative glass transition temperature, such as Pd40Ni40P20, homogeneous nucleation also becomes negligible. Large (5g) masses of this alloys were obtained using a molten B2O3 flux. Presently, bulk glass formation in iron based glasses is being investigated. It is expected that if an undercooling of about 250K can be achieved in a Ge or Si melt, formation of the amorphous semiconductor phase (rather than the crystal) may be kinetically favored. The volumetric behavior of undercooled liquid Ga droplet dispersion is investigated by dilatometry. A theoretical model (both analytical and numerical) was developed for transient nucleation in glass forming melts. The model, originally designed for isothermal conditions, was extended to continuous quenching. It is being applied to glass formation in various metallic and oxide systems. A further refinement will be the inclusion of diffusion controlled interfacial rearrangements governing the growth of the crystal embryos.

  3. Performance of magneto-optical glass in optical current transducer application

    NASA Astrophysics Data System (ADS)

    Shen, Yan; Lu, Yunhe; Liu, Zhao; Yu, Xueliang; Zhang, Guoqing; Yu, Wenbin

    2015-09-01

    First, a theoretical analysis was performed on the effect of temperature on the performance of the sensing element of paramagnetic rare earth-doped magneto-optical glass material that can be used in an optical current transducer application. The effect comprises two aspects: the linear birefringence and the Verdet constant. On this basis, rare earth-doped glass temperature characteristics were studied, and the experimental results indicated that the linear birefringence of rare earth-doped glass increased with increasing temperature, while its magneto-optical sensitivity decreased. Comparative experiments performed for various concentrations of rare earth dopant in the glass revealed that changes in the dopant concentration had no significant effect on the performance of magneto-optical glass. At last, a comparison between rare earth-doped magneto-optical and diamagnetic dense flint glass showed that the sensitivity of the former was six times that of the latter, although the temperature stability of the former was poorer.

  4. Bulk Formation of Metallic Glasses and Amorphous Silicon from the Melt

    NASA Technical Reports Server (NTRS)

    Spaepen, F.

    1985-01-01

    By using metallic glass compositions with a high relative glass transition temperature, such as Pd40Ni40P20, homogeneous nucleation also becomes negligible. Large (5g) masses of this alloys were obtained using a molten B2O3 flux. Presently, bulk glass formation in iron based glasses is being investigated. It is expected that if an undercooling of about 250K can be achieved in a Ge or Si melt, formation of the amorphous semiconductor phase (rather than the crystal) may be kinetically favored. The volumetric behavior of undercooled liquid Ga droplet dispersion is investigated by dilatometry. A theoretical model (both analytical and numerical) was developed for transient nucleation in glass forming melts. The model, originally designed for isothermal conditions, was extended to continuous quenching. It is being applied to glass formation in various metallic and oxide systems. A further refinement will be the inclusion of diffusion controlled interfacial rearrangements governing the growth of the crystal embryos.

  5. Spin Glass Patch Planting

    NASA Technical Reports Server (NTRS)

    Wang, Wenlong; Mandra, Salvatore; Katzgraber, Helmut G.

    2016-01-01

    In this paper, we propose a patch planting method for creating arbitrarily large spin glass instances with known ground states. The scaling of the computational complexity of these instances with various block numbers and sizes is investigated and compared with random instances using population annealing Monte Carlo and the quantum annealing DW2X machine. The method can be useful for benchmarking tests for future generation quantum annealing machines, classical and quantum mechanical optimization algorithms.

  6. PREFACE: Viewing the World through Spin Glasses

    NASA Astrophysics Data System (ADS)

    Coolen, Ton; Nishimori, Hidetoshi; Sourlas, Nicolas; Wong, Michael

    2008-08-01

    This special issue of Journal of Physics A: Mathematical and Theoretical collects papers by speakers and participants of the conference `Viewing the World through Spin Glasses', held in Oxford (UK) on 31 August and 1 September 2007 in honour of Professor David Sherrington. It also includes contributions by many other active researchers in the field of spin glasses and related problems. The theory of spin glasses has a history of more than 30 years and continues to develop within itself as well as into an unexpectedly vast range of interdisciplinary subjects, including neural networks, error-correcting codes, optimization problems and social problems. Most of these amazing developments have their formal basis in the ground-breaking work of David Sherrington with Scott Kirkpatrick, centred on the SK model and the techniques devised to analyse it via the replica method. In this 'classic-of-classics' paper, a theoretical paradigm was suddenly established which became the common tool of analysis for thousands of papers in the following decades. It also led to deep developments in probability theory, through the efforts to understand the enigmatic Parisi solution of the SK model. The work of Professor Sherrington will continue to be an infinite source of our inspiration in many years to come. The purpose of the conference `Viewing the World through Spin Glasses' was to provide an overview of the present status of the fields which Professor Sherrington initiated, on the occasion of his 65th birthday, organized by John Cardy, Juan P Garrahan and the present Guest Editors. The first contribution in this special issue, by Professor Paul Goldbart, reflects his salute delivered at the conference dinner, and conveys its atmosphere very well. The papers that follow, ordered by the date of acceptance, represent the current activities of leading researchers in spin glasses and related fields, and we expect these to serve as milestones for future developments. We thank all the

  7. Polyamorphism in metalic glass.

    SciTech Connect

    Sheng, H. W.; Liu, H. Z.; Cheng, Y. Q.; Wen, J.; Lee, P.L.; Luo, W.K.; Shastri, S.D.; Ma, E.; X-Ray Science Division; Johns Hopkins Univ.; Chinese Academy of Sciences

    2007-03-01

    A metal, or an alloy, can often exist in more than one crystal structure. The face-centered-cubic and body-centered-cubic forms of iron (or steel) are a familiar example of such polymorphism. When metallic materials are made in the amorphous form, is a parallel 'polyamorphism' possible? So far, polyamorphic phase transitions in the glassy state have been observed only in glasses involving directional and open (such as tetrahedral) coordination environments. Here, we report an in situ X-ray diffraction observation of a pressure-induced transition between two distinct amorphous polymorphs in a Ce{sub 55}Al{sub 45} metallic glass. The large density difference observed between the two polyamorphs is attributed to their different electronic and atomic structures, in particular the bond shortening revealed by ab initio modeling of the effects of f-electron delocalization. This discovery offers a new perspective of the amorphous state of metals, and has implications for understanding the structure, evolution and properties of metallic glasses and related liquids. Our work also opens a new avenue towards technologically useful amorphous alloys that are compositionally identical but with different thermodynamic, functional and rheological properties due to different bonding and structural characteristics.

  8. Picritic glasses from Hawaii

    USGS Publications Warehouse

    Clague, D.A.; Weber, W.S.; Dixon, J.E.

    1991-01-01

    ESTIMATES of the MgO content of primary Hawaiian tholeiitic melts range from 8wt% to as high as 25wt% (refs 1, 2). In general, these estimates are derived from analysis of the whole-rock composition of lavas, coupled with the compositions of the most magnesian olivine phenocrysts observed. But the best estimate of magma composition comes from volcanic glass, as it represents the liquid composition at the time of quenching; minimal changes occur during the quenching process. Here we report the discovery of tholeiitic basalt glasses, recovered offshore of Kilauea volcano, that contain up to 15.0 wt% MgO. To our knowledge, these are the most magnesian glasses, and have the highest eruption temperatures (??? 1,316 ??C), yet found. The existence of these picritic (high-MgO) liquids provides constraints on the temperature structure of the upper mantle, magma transport and the material and thermal budgets of the Hawaiian volcanoes. Furthermore, picritic melts are affected little by magma-reservoir processes, and it is therefore relatively straightforward to extrapolate back to the composition of the primary melt and its volatile contents.

  9. Gender in Early Childhood.

    ERIC Educational Resources Information Center

    Yelland, Nicola, Ed.

    The construction of gender is a systematic process that begins at birth and is continually shaped, molded, and reshaped throughout life. This book examines practices with young children with respect to the construction of gender and the expectations of society, schools, and families. The book is organized into two parts. The first part considers…

  10. Gender and Psychological Distress.

    ERIC Educational Resources Information Center

    Cook, Ellen Piel

    1990-01-01

    Contends that, to understand role of gender in psychological problems, counselors need to be aware of gender-socialized individual characteristics, which may affect what psychological problems people develop, associated symptoms, and how people respond to problems. Claims it is important to recognize how broader sociological context presents men…

  11. Gender Equity. IDRA Forum.

    ERIC Educational Resources Information Center

    IDRA Newsletter, 1994

    1994-01-01

    This newsletter contains six articles on issues of gender equity for Chicanas and other women. "Recognizing Chicana Contributions: Cultural History & Gender Equity on the Line" (Mikki Symonds) discusses the invisibility of Mexican Americans in general and of Chicanas in particular in U.S. history books, school curricula, and pop…

  12. Issues of Gender. Symposium.

    ERIC Educational Resources Information Center

    2002

    This symposium is comprised of three papers on issues of gender in human resource development (HRD). "The Impact of Awareness and Action on the Implementation of a Women's Network" (Laura L. Bierema) reports on research to examine how gender consciousness emerges through the formation of in-company networks to promote corporate women's…

  13. Gender, Toys and Learning

    ERIC Educational Resources Information Center

    Francis, Becky

    2010-01-01

    In spite of continuing patterning of curriculum subject preference and choice by gender, there has been little recent attention to the argument developed in the 1970s that children play with different toys according to their gender, and that these provide girls and boys with (different) curriculum-related skills. The article describes a…

  14. Grammatical Gender in Translation

    ERIC Educational Resources Information Center

    Bordag, Denisa; Pechmann, Thomas

    2008-01-01

    In three experiments native speakers of Czech translated bare nouns and gender-marked adjective + noun phrases into German, their second language (L2). In Experiments 1-3 we explored the so-called gender interference effect from first language (L1) as observed in previous picture naming studies (naming latencies were longer when the L1 noun and…

  15. Gender-Friendly Schools

    ERIC Educational Resources Information Center

    King, Kelley; Gurian, Michael; Stevens, Kathy

    2010-01-01

    The authors, who have worked with more than 2,000 schools across the United States in efforts to close gender gaps, describe how gender-related issues consistently intersect and interfere with school improvement efforts. They present statistics showing that schools are now failing boys in more areas than girls, and describe how "the…

  16. The Gender Reality Hypothesis

    ERIC Educational Resources Information Center

    Lippa, Richard A.

    2006-01-01

    Comments on the article by J. S. Hyde (see record 2005-11115-001), in which Hyde reviewed meta-analytic evidence on gender differences and concluded that most psychological gender differences are in the close-to-zero or small range. The current author notes some omissions from Hyde's review, including the findings through other research large…

  17. Gender Roles and Coping.

    ERIC Educational Resources Information Center

    Patterson, Joan M.; McCubbin, Hamilton I.

    1984-01-01

    Examined the relationship of gender-role orientation and specific behavioral coping responses of wives (N=82) experiencing a long-term separation from their military spouses. Results showed that an androgynous gender-role orientation was significantly associated with four of the five coping patterns identified as helpful to wives managing a…

  18. Interrupting Gendered Assessment Practices.

    ERIC Educational Resources Information Center

    Hildebrand, Gaell M.

    This paper is part of the symposium on "Gender and Assessment of Physics in Context: Getting It Right!" It examines ways in which current practices privilege the "masculine" over the "feminine" and presents an agenda for gender inclusive assessment practices. It is argued that physics like other domains of knowledge,…

  19. Gender and Psychological Distress.

    ERIC Educational Resources Information Center

    Cook, Ellen Piel

    1990-01-01

    Contends that, to understand role of gender in psychological problems, counselors need to be aware of gender-socialized individual characteristics, which may affect what psychological problems people develop, associated symptoms, and how people respond to problems. Claims it is important to recognize how broader sociological context presents men…

  20. Gender in Early Childhood.

    ERIC Educational Resources Information Center

    Yelland, Nicola, Ed.

    The construction of gender is a systematic process that begins at birth and is continually shaped, molded, and reshaped throughout life. This book examines practices with young children with respect to the construction of gender and the expectations of society, schools, and families. The book is organized into two parts. The first part considers…

  1. Are Numbers Gendered?

    ERIC Educational Resources Information Center

    Wilkie, James E. B.; Bodenhausen, Galen V.

    2012-01-01

    We examined the possibility that nonsocial, highly generic concepts are gendered. Specifically, we investigated the gender connotations of Arabic numerals. Across several experiments, we show that the number 1 and other odd numbers are associated with masculinity, whereas the number 2 and other even numbers are associated with femininity, in ways…

  2. Gender Inequality at Work.

    ERIC Educational Resources Information Center

    Jacobs, Jerry A., Ed.

    These 14 papers address many dimensions of gender inequality at work. The empirical studies include examinations of original surveys, secondary analyses of large data sets, and historical reports assaying the significance of personal, family, and structural factors with regard to gender in the workplace. An introduction (Jacobs) sketches how sex…

  3. Gender and Peer Response

    ERIC Educational Resources Information Center

    Tomlinson, Elizabeth

    2009-01-01

    This case study examines written peer response materials generated by small groups with varying gender compositions. Based on those observations, the author offers several pedagogical implications. She suggests that groups' gender make-up often does influence written feedback provided by group members during peer response sessions. By better…

  4. Are Numbers Gendered?

    ERIC Educational Resources Information Center

    Wilkie, James E. B.; Bodenhausen, Galen V.

    2012-01-01

    We examined the possibility that nonsocial, highly generic concepts are gendered. Specifically, we investigated the gender connotations of Arabic numerals. Across several experiments, we show that the number 1 and other odd numbers are associated with masculinity, whereas the number 2 and other even numbers are associated with femininity, in ways…

  5. Grammatical Gender in Translation

    ERIC Educational Resources Information Center

    Bordag, Denisa; Pechmann, Thomas

    2008-01-01

    In three experiments native speakers of Czech translated bare nouns and gender-marked adjective + noun phrases into German, their second language (L2). In Experiments 1-3 we explored the so-called gender interference effect from first language (L1) as observed in previous picture naming studies (naming latencies were longer when the L1 noun and…

  6. Gender, Toys and Learning

    ERIC Educational Resources Information Center

    Francis, Becky

    2010-01-01

    In spite of continuing patterning of curriculum subject preference and choice by gender, there has been little recent attention to the argument developed in the 1970s that children play with different toys according to their gender, and that these provide girls and boys with (different) curriculum-related skills. The article describes a…

  7. Gender-Friendly Schools

    ERIC Educational Resources Information Center

    King, Kelley; Gurian, Michael; Stevens, Kathy

    2010-01-01

    The authors, who have worked with more than 2,000 schools across the United States in efforts to close gender gaps, describe how gender-related issues consistently intersect and interfere with school improvement efforts. They present statistics showing that schools are now failing boys in more areas than girls, and describe how "the…

  8. Gender and the JRME.

    ERIC Educational Resources Information Center

    Fennema, Elizabeth; Hart, Laurie E.

    1994-01-01

    Addresses two questions: (1) How has gender and mathematics been treated in the "Journal for Research in Mathematics Education" (JRME), and how does that record fit into the broader societal concern with gender and mathematics? (2) What kinds of studies should be published in the future to achieve equity for females in mathematics? (31…

  9. Method of Estimating Continuous Cooling Transformation Curves of Glasses

    NASA Technical Reports Server (NTRS)

    Zhu, Dongmei; Zhou, Wancheng; Ray, Chandra S.; Day, Delbert E.

    2006-01-01

    A method is proposed for estimating the critical cooling rate and continuous cooling transformation (CCT) curve from isothermal TTT data of glasses. The critical cooling rates and CCT curves for a group of lithium disilicate glasses containing different amounts of Pt as nucleating agent estimated through this method are compared with the experimentally measured values. By analysis of the experimental and calculated data of the lithium disilicate glasses, a simple relationship between the crystallized amount in the glasses during continuous cooling, X, and the temperature of undercooling, (Delta)T, was found to be X = AR(sup-4)exp(B (Delta)T), where (Delta)T is the temperature difference between the theoretical melting point of the glass composition and the temperature in discussion, R is the cooling rate, and A and B are constants. The relation between the amount of crystallisation during continuous cooling and isothermal hold can be expressed as (X(sub cT)/X(sub iT) = (4/B)(sup 4) (Delta)T(sup -4), where X(sub cT) stands for the crystallised amount in a glass during continuous cooling for a time t when the temperature comes to T, and X(sub iT) is the crystallised amount during isothermal hold at temperature T for a time t.

  10. Temperature dependent evolution of dynamic heterogeneity in metallic glass

    NASA Astrophysics Data System (ADS)

    Luo, P.; Li, M. X.; Jiang, H. Y.; Wen, P.; Bai, H. Y.; Wang, W. H.

    2017-04-01

    Substantial efforts in theoretical and experimental studies have demonstrated that the dynamics in supercooled liquids is spatially heterogeneous. However, a complete description concerning the dynamic heterogeneity evolution from liquid to rigid glass is still lacking. Here, by a combining study of the dynamic and static mechanical responses, we quantify the characterization of dynamic heterogeneity and its temperature evolution spanning an unprecedented broad temperature range in metallic glass. We show that the dynamic heterogeneity persists from the warm liquid state into the rigid glassy state and becomes progressively pronounced with cooling, accompanied by increasing breadth of the relaxation rate dispersion.

  11. Gender dysphoria and children.

    PubMed

    Nicholson, Chance; McGuinness, Teena M

    2014-08-01

    The age at which gender dysphoria can be diagnosed with enough certainty to justify medical intervention is controversial. The aim of this article is to explore current literature as it relates to the gender reassignment process and diagnostic indicators supporting an appropriate age for intervention. The timing of diagnosis and treatment of gender dysphoria remains the center of debate between the long-term effects of early intervention versus delay of treatment. Limited research is available on gender dysphoria treatment protocols for children. However, preliminary studies suggest that early intervention improves the quality of life in individuals who are transgender. Ongoing research suggests that it may be possible to confirm gender dysphoria at an earlier age.

  12. Mixed polyanion glass cathodes: Glass-state conversion reactions

    DOE PAGES

    Kercher, Andrew K.; Kolopus, James A.; Carroll, Kyler; ...

    2015-01-01

    Mixed polyanion (MP) glasses can undergo glass-state conversion (GSC) reactions to provide an alternate class of high-capacity cathode materials. GSC reactions have been demonstrated in phosphate/vanadate glasses with Ag, Co, Cu, Fe, and Ni cations. These MP glasses provided high capacity and good high power performance, but suffer from moderate voltages, large voltage hysteresis, and significant capacity fade with cycling. Details of the GSC reaction have been revealed by x-ray absorption spectroscopy, electron microscopy, and energy dispersive x-ray spectroscopy of ex situ cathodes at key states of charge. Using the Open Quantum Materials Database (OQMD), a computational thermodynamic model hasmore » been developed to predict the near-equilibrium voltages of glass-state conversion reactions in MP glasses.« less

  13. Laser Glass Frit Sealing for Encapsulation of Vacuum Insulation Glasses

    NASA Astrophysics Data System (ADS)

    Kind, H.; Gehlen, E.; Aden, M.; Olowinsky, A.; Gillner, A.

    Laser glass frit sealing is a joining method predestined in electronics for the sealing of engineered materials housings in dimensions of some 1 mm2 to several 10 mm2. The application field ranges from encapsulation of display panels to sensor housings. Laser glass frit sealing enables a hermetical closure excluding humidity and gas penetration. But the seam quality is also interesting for other applications requiring a hermetical sealing. One application is the encapsulation of vacuum insulation glass. The gap between two panes must be evacuated for reducing the thermal conductivity. Only an efficient encapsulating technique ensures durable tight joints of two panes for years. Laser glass frit sealing is an alternative joining method even though the material properties of soda lime glass like sensitivity to thermal stresses are much higher as known from engineered materials. An adapted thermal management of the process is necessary to prevent the thermal stresses within the pane to achieve crack free and tight glass frit seams.

  14. Mixed polyanion glass cathodes: Glass-state conversion reactions

    SciTech Connect

    Kercher, Andrew K.; Kolopus, James A.; Carroll, Kyler; Unocic, Raymond R.; Kirklin, S.; Wolverton, C.; Stooksbury, Shelby L.; Boatner, Lynn A.; Dudney, Nancy J.

    2015-01-01

    Mixed polyanion (MP) glasses can undergo glass-state conversion (GSC) reactions to provide an alternate class of high-capacity cathode materials. GSC reactions have been demonstrated in phosphate/vanadate glasses with Ag, Co, Cu, Fe, and Ni cations. These MP glasses provided high capacity and good high power performance, but suffer from moderate voltages, large voltage hysteresis, and significant capacity fade with cycling. Details of the GSC reaction have been revealed by x-ray absorption spectroscopy, electron microscopy, and energy dispersive x-ray spectroscopy of ex situ cathodes at key states of charge. Using the Open Quantum Materials Database (OQMD), a computational thermodynamic model has been developed to predict the near-equilibrium voltages of glass-state conversion reactions in MP glasses.

  15. Impact resistance of bar glasses.

    PubMed

    Shepherd, J P; Huggett, R H; Kidner, G

    1993-12-01

    Bar glasses are often used as weapons in interpersonal violence. Violence often erupts spontaneously and assailants use objects close to hand as weapons. After an initial national Accident and Emergency Department study to identify glass designs most often implicated in interpersonal violence, the impact resistance of 1-pint beer glasses was tested in a materials laboratory with a Zwick 5102 pendulum impact tester. Both straight-sided (nonik) glasses (annealed and tempered) and handled tankards (annealed) were tested to destruction. The impact resistance of new glasses was compared with that of glasses subjected to wear. The mean impact resistance of new annealed noniks did not differ significantly although new glasses were significantly more resistant than worn glasses (p < 0.01). It was not possible to break any of the tempered glasses with the pendulum used (maximum impact energy, 4 J). When noniks had been scratched at the rim to mimic wear, tempered glasses also had the highest impact resistance (p < 0.01) whereas the mean resistance of the annealed noniks was not significantly different. When tempered glasses failed during testing, they all disintegrated into relatively harmless cubes of glass, particularly the thicker bases of glasses. In contrast, annealed designs fractured leaving sharp shards although the thicker bases remained intact. The mean impact resistance of new annealed noniks was 0.5 J, of worn annealed noniks 0.08 J, of tempered new noniks > 4 J, of worn tempered noniks 0.18 J, and of tankards, 1.7 J.(ABSTRACT TRUNCATED AT 250 WORDS)

  16. Bioactive glass in tissue engineering

    PubMed Central

    Rahaman, Mohamed N.; Day, Delbert E.; Bal, B. Sonny; Fu, Qiang; Jung, Steven B.; Bonewald, Lynda F.; Tomsia, Antoni P.

    2011-01-01

    This review focuses on recent advances in the development and use of bioactive glass for tissue engineering applications. Despite its inherent brittleness, bioactive glass has several appealing characteristics as a scaffold material for bone tissue engineering. New bioactive glasses based on borate and borosilicate compositions have shown the ability to enhance new bone formation when compared to silicate bioactive glass. Borate-based bioactive glasses also have controllable degradation rates, so the degradation of the bioactive glass implant can be more closely matched to the rate of new bone formation. Bioactive glasses can be doped with trace quantities of elements such as Cu, Zn and Sr, which are known to be beneficial for healthy bone growth. In addition to the new bioactive glasses, recent advances in biomaterials processing have resulted in the creation of scaffold architectures with a range of mechanical properties suitable for the substitution of loaded as well as non-loaded bone. While bioactive glass has been extensively investigated for bone repair, there has been relatively little research on the application of bioactive glass to the repair of soft tissues. However, recent work has shown the ability of bioactive glass to promote angiogenesis, which is critical to numerous applications in tissue regeneration, such as neovascularization for bone regeneration and the healing of soft tissue wounds. Bioactive glass has also been shown to enhance neocartilage formation during in vitro culture of chondrocyte-seeded hydrogels, and to serve as a subchondral substrate for tissue-engineered osteochondral constructs. Methods used to manipulate the structure and performance of bioactive glass in these tissue engineering applications are analyzed. PMID:21421084

  17. Analytical Plan for Roman Glasses

    SciTech Connect

    Strachan, Denis M.; Buck, Edgar C.; Mueller, Karl T.; Schwantes, Jon M.; Olszta, Matthew J.; Thevuthasan, Suntharampillai; Heeren, Ronald M.

    2011-01-01

    Roman glasses that have been in the sea or underground for about 1800 years can serve as the independent “experiment” that is needed for validation of codes and models that are used in performance assessment. Two sets of Roman-era glasses have been obtained for this purpose. One set comes from the sunken vessel the Iulia Felix; the second from recently excavated glasses from a Roman villa in Aquileia, Italy. The specimens contain glass artifacts and attached sediment or soil. In the case of the Iulia Felix glasses quite a lot of analytical work has been completed at the University of Padova, but from an archaeological perspective. The glasses from Aquileia have not been so carefully analyzed, but they are similar to other Roman glasses. Both glass and sediment or soil need to be analyzed and are the subject of this analytical plan. The glasses need to be analyzed with the goal of validating the model used to describe glass dissolution. The sediment and soil need to be analyzed to determine the profile of elements released from the glass. This latter need represents a significant analytical challenge because of the trace quantities that need to be analyzed. Both pieces of information will yield important information useful in the validation of the glass dissolution model and the chemical transport code(s) used to determine the migration of elements once released from the glass. In this plan, we outline the analytical techniques that should be useful in obtaining the needed information and suggest a useful starting point for this analytical effort.

  18. Exposure assessment in epidemiology: does gender matter?

    PubMed

    Kennedy, Susan M; Koehoorn, Mieke

    2003-12-01

    The pathway from potential hazards in the work environment to the measurement or estimation of personal exposure for epidemiologic studies comprises many steps, each of which can be influenced by factors that may or may not differ by gender. This article explores this pathway to address the question, "Should the potential for gender differences be taken into account in the activity of exposure assessment for epidemiologic studies?" Evidence from previously published studies and data from the investigators' own research were examined to explore whether or not several theoretical sources of gender 'bias' in exposure assessment have been found in actual studies. Sources of bias examined included: differences in job tasks despite same job titles; differences in delivered exposure due to differences in protective equipment, body size, or other relationships to exposure sources; and differences in estimated exposure arising from study methods or design. Evidence was found for gender differences (and thus potential bias) from all these sources, at least in some studies. We conclude that the answer to the question posed, "Does gender matter, in exposure assessment for epidemiology?" is a qualified 'yes,' but that the magnitude and direction of the potential bias cannot be predicted, a priori. Am. J. Ind. Med. 44:576-583, 2003. Copyright 2003 Wiley-Liss, Inc.

  19. Gender conflict and worldview defence.

    PubMed

    Fritsche, Immo; Jonas, Eva

    2005-12-01

    Applying social identity and terror management theory assumptions to gender conflict we predicted that mortality salience (MS) would lead to an increase in pro-women attitudes in women and a decrease in these attitudes in men. After a MS versus control manipulation, 32 female and 24 male university students evaluated (fictitious) courses in psychology dealing with and supporting the promotion of women. In accordance with our prediction the results showed a significant interaction between sex and MS, indicating that men and women differed in their judgment only under MS but not in the control condition. Whereas men reacted with an increased negative evaluation of the pro-women courses following MS, women on the other hand showed an increased positive evaluation of the courses. Theoretical and practical implications are discussed.

  20. Doing Gender in Management Education.

    ERIC Educational Resources Information Center

    Marshall, Judi

    1999-01-01

    Explores teaching gender to management students, mainly those working toward Masters in Business Administration degrees. Introduces a gender awareness approach and illustrates it with two examples of "doing" gender using multiple associations of that term. (SLD)

  1. Gender nonconforming youth: current perspectives.

    PubMed

    Ehrensaft, Diane

    2017-01-01

    Beginning with a case vignette, a discussion follows of the reformulation of theories of gender development taking into consideration the recent upsurge of gender nonconforming and transgender youth presenting for gender services and also in the culture at large. The three predominant models of pediatric gender care are reviewed and critiqued, along with a presentation of the recently developed interdisciplinary model of gender care optimal in the treatment of gender nonconforming youth seeking either puberty blockers or cross-sex hormones.

  2. "Don't Be Such a Baby!" Competence and Age as Intersectional Co-Markers on Children's Gender

    ERIC Educational Resources Information Center

    Hellman, Anette; Heikkilä, Mia; Sundhall, Jeanette

    2014-01-01

    The aim of this paper is to show how norms about age intersect with gender and thus create social positions about incompetent and competent children. The paper also analyzes the relationship between gender, incompetence, and notions of "the baby." The theoretical framework uses concepts taken from gender theory (Butler, "Gender…

  3. Dominant toughening mechanisms in barium aluminosilicate (BAS) glass-ceramics

    NASA Astrophysics Data System (ADS)

    Griggs, Jason Alan

    The purpose of this study was to develop a barium aluminosilicate (BAS) glass-ceramic with improved strength and fracture toughness by controlling the morphology of the constituent phases through a series of thermal crystallization treatments. The specific objectives of this study were to (1) determine which toughening mechanisms are active in the BAS system, (2) provide quantitative estimates of the relative contributions of those mechanisms, and (3) identify the processing conditions that correspond to a glass-ceramic with optimal fracture toughness. The BAS system was chosen for this study because of its potential applications in CAD-CAM production of dental prostheses. It is concluded that load sharing and crack deflection are the only major sources of toughening in the BAS system. Theoretical predictions for toughening increases due to load sharing and crack deflection are insufficient to account for 100% of the increases observed. The excess increase in fracture toughness is produced by thermal mismatch between and crystal and glass phases. The strength and fracture toughness of BAS glass-ceramics are shown to increase with increasing crystal growth time over the entire range of treatments studied. The strength and fracture toughness increased from 63 ± 8 MPa and 0.89 ± 0.05 MPa*msp{1/2}, respectively for BAS glass to 141 ± 8 MPa and 1.87 ± 0.07 MPa*msp{1/2} respectively for a glass-ceramic treated for 256 h at 975sp°C. Fracture toughness was also shown to increase with increasing mean crystal size. A non-stoichiometric glass composition results in thermal compatibility between the glass and crystal phases, eliminating the weakening at large crystal sizes that can be associated with a spontaneous microcracking mechanism.

  4. High-Entropy Metallic Glasses

    NASA Astrophysics Data System (ADS)

    Wang, W. H.

    2014-10-01

    The high-entropy alloys are defined as solid-solution alloys containing five or more than five principal elements in equal or near-equal atomic percent. The concept of high mixing entropy introduces a new way for developing advanced metallic materials with unique physical and mechanical properties that cannot be achieved by the conventional microalloying approach based on only a single base element. The metallic glass (MG) is the metallic alloy rapidly quenched from the liquid state, and at room temperature it still shows an amorphous liquid-like structure. Bulk MGs represent a particular class of amorphous alloys usually with three or more than three components but based on a single principal element such as Zr, Cu, Ce, and Fe. These materials are very attractive for applications because of their excellent mechanical properties such as ultrahigh (near theoretical) strength, wear resistance, and hardness, and physical properties such as soft magnetic properties. In this article, we review the formation and properties of a series of high-mixing-entropy bulk MGs based on multiple major elements. It is found that the strategy and route for development of the high-entropy alloys can be applied to the development of the MGs with excellent glass-forming ability. The high-mixing-entropy bulk MGs are then loosely defined as metallic glassy alloys containing five or more than five elements in equal or near-equal atomic percent, which have relatively high mixing entropy compared with the conventional MGs based on a single principal element. The formation mechanism, especially the role of the mixing entropy in the formation of the high-entropy MGs, is discussed. The unique physical, mechanical, chemical, and biomedical properties of the high-entropy MGs in comparison with the conventional metallic alloys are introduced. We show that the high-mixing-entropy MGs, along the formation idea and strategy of the high-entropy alloys and based on multiple major elements, might provide

  5. A framework to analyse gender bias in epidemiological research.

    PubMed

    Ruiz-Cantero, María Teresa; Vives-Cases, Carmen; Artazcoz, Lucía; Delgado, Ana; García Calvente, Maria Mar; Miqueo, Consuelo; Montero, Isabel; Ortiz, Rocío; Ronda, Elena; Ruiz, Isabel; Valls, Carme

    2007-12-01

    The design and analysis of research may cause systematic gender dependent errors to be produced in results because of gender insensitivity or androcentrism. Gender bias in research could be defined as a systematically erroneous gender dependent approach related to social construct, which incorrectly regards women and men as similar/different. Most gender bias can be found in the context of discovery (development of hypotheses), but it has also been found in the context of justification (methodological process), which must be improved. In fact, one of the main effects of gender bias in research is partial or incorrect knowledge in the results, which are systematically different from the real values. This paper discusses some forms of conceptual and methodological bias that may affect women's health. It proposes a framework to analyse gender bias in the design and analysis of research carried out on women's and men's health problems, and on specific women's health issues. Using examples, the framework aims to show the different theoretical perspectives in a social or clinical research context where forms of selection, measurement and confounding bias are produced as a result of gender insensitivity. Finally, this paper underlines the importance of re-examining results so that they may be reinterpreted to produce new gender based knowledge.

  6. Occupational therapists' perceptions of gender - a focus group study.

    PubMed

    Liedberg, Gunilla M; Björk, Mathilda; Hensing, Gunnel

    2010-10-01

    Women and men are shaped over the courses of their lives by culture, society and human interaction according to the gender system. Cultural influences on individuals' social roles and environment are described in occupational therapy literature, but not specifically from a gender perspective. The purpose of this qualitative study was to explore how a sample of occupational therapists perceives the 'gender' concept. Four focus group interviews with 17 occupational therapists were conducted. The opening question was: 'How do you reflect on the encounter with a client depending on whether it is a man or a woman?' The transcribed interviews were analysed and two main themes emerged: 'the concept of gender is tacit in occupational therapy' and 'client encounters'. The occupational therapists expressed limited theoretical knowledge of 'gender'. Furthermore, the occupational therapists seemed to be 'doing gender' in their encounters with the clients. For example, in their assessment of the client, they focussed their questions on different spheres: with female clients, on the household and family; with male clients, on their paid work. This study demonstrated that occupational therapists were unaware of the possibility that they were 'doing gender' in their encounters with clients. There is a need to increase occupational therapists' awareness of their own behaviour of 'doing gender'. Furthermore, there is a need to investigate whether gendered perceptions will shorten or lengthen a rehabilitation period and affect the chosen interventions, and in the end, the outcome for the clients. © 2010 The Authors. Australian Occupational Therapy Journal © 2010 Australian Association of Occupational Therapists.

  7. A framework to analyse gender bias in epidemiological research

    PubMed Central

    Ruiz‐Cantero, María Teresa; Vives‐Cases, Carmen; Artazcoz, Lucía; Delgado, Ana; del Mar García Calvente, Maria; Miqueo, Consuelo; Montero, Isabel; Ortiz, Rocío; Ronda, Elena; Ruiz, Isabel; Valls, Carme

    2007-01-01

    The design and analysis of research may cause systematic gender dependent errors to be produced in results because of gender insensitivity or androcentrism. Gender bias in research could be defined as a systematically erroneous gender dependent approach related to social construct, which incorrectly regards women and men as similar/different. Most gender bias can be found in the context of discovery (development of hypotheses), but it has also been found in the context of justification (methodological process), which must be improved. In fact, one of the main effects of gender bias in research is partial or incorrect knowledge in the results, which are systematically different from the real values. This paper discusses some forms of conceptual and methodological bias that may affect women's health. It proposes a framework to analyse gender bias in the design and analysis of research carried out on women's and men's health problems, and on specific women's health issues. Using examples, the framework aims to show the different theoretical perspectives in a social or clinical research context where forms of selection, measurement and confounding bias are produced as a result of gender insensitivity. Finally, this paper underlines the importance of re‐examining results so that they may be reinterpreted to produce new gender based knowledge. PMID:18000118

  8. Managing gender diversity in healthcare: getting it right.

    PubMed

    Vanderbroeck, Paul; Wasserfallen, Jean-Blaise

    2017-02-06

    Purpose Diversity, notably gender diversity, is growing in health care, both at the level of teams and the level of organizations. This paper aims to describe the challenges for team leaders and leaders of organizations to manage this diversity. The authors believe that more could be done to help leaders master these challenges in a way that makes diverse teams and organizations more productive. Design/methodology/approach Drawing on previously published research, using gender diversity as an example, the paper first describes how diversity can both have a positive and a negative influence on team productivity. Next, it describes the challenge of gender diversity at an organizational level, using Switzerland as an example. Findings The first part of the paper espouses the causes of gender diversity, undoes some of the myths surrounding diversity and presents a model for effective management of diversity in teams. The second part looks at gender diversity at an organizational level. Drawing from sources inside and outside healthcare, the effects of the "leaking pipeline", "glass wall" and "glass ceiling" that prevent health-care organizations from leveraging the potential of female talent are discussed. Practical implications The authors propose a model developed for intercultural teamwork as a framework for leveraging gender diversity for better team productivity. Proposals are offered to health-care organizations on how they can tip the gender balance at senior levels into their favor, so as to get the maximum benefit from the available talent. Originality/value Applying the "how to" ideas and recommendations from this general review will help leaders of health-care organizations gain a better return on investment from their talent development as well as to increase the productivity of their workforce by a better use of diverse talent.

  9. Fracture mechanics of cellular glass

    NASA Technical Reports Server (NTRS)

    Zwissler, J. G.; Adams, M. A.

    1981-01-01

    The fracture mechanics of cellular glasses (for the structural substrate of mirrored glass for solr concentrator reflecting panels) are discussed. Commercial and developmental cellular glasses were tested and analyzed using standard testing techniques and models developed from linear fracture mechanics. Two models describing the fracture behavior of these materials were developed. Slow crack growth behavior in cellular glass was found to be more complex than that encountered in dense glasses or ceramics. The crack velocity was found to be strongly dependent upon water vapor transport to the tip of the moving crack. The existence of a static fatigue limit was not conclusively established, however, it is speculated that slow crack growth behavior in Region 1 may be slower, by orders of magnitude, than that found in dense glasses.

  10. Waste product profile: Glass containers

    SciTech Connect

    Miller, C.

    1995-09-01

    In 1992, Waste Age initiated the Waste Product Profile series -- brief, factual listings of the solid waste management characteristics of materials in the solid waste stream. This popular series of profiles high-lighted a product, explained how it fit into integrated waste management systems, and provided current data on recycling and markets for the product. Glass containers are made from sand, limestone, soda ash, cullet (crushed bottles), and various additives, including those used to produce green, brown, and blue glass. Other glass products include flat glass, such as windows, and fiberglass products, such as insulation and glassware. These products are manufactured using different processes and different additives than container glass. This profile covers only glass containers.

  11. Relaxation Pathways in Metallic Glasses

    NASA Astrophysics Data System (ADS)

    Gallino, Isabella; Busch, Ralf

    2017-09-01

    At temperatures below the glass transition temperature, physical properties of metallic glasses, such as density, viscosity, electrical resistivity or enthalpy, slowly evolve with time. This is the process of physical aging that occurs among all types of glasses and leads to structural changes at the microscopic level. Even though the relaxation pathways are ruled by thermodynamics as the glass attempts to re-attain thermodynamic equilibrium, they are steered by sluggish kinetics at the microscopic level. Understanding the structural and dynamic pathways of the relaxing glassy state is still one of the grand challenges in materials physics. We review some of the recent experimental advances made in understanding the nature of the relaxation phenomenon in metallic glasses and its implications to the macroscopic and microscopic properties changes of the relaxing glass.

  12. Gender training: creating change.

    PubMed

    Craun-selka, P

    1997-01-01

    Over the last 20 years, the Centre for Development and Population Activities (CEDPA) has developed a training program concerning gender policies and practices; it includes a curriculum, "Gender and Development," and a handbook, "Gender Equity: Concepts and Tools for Development." Gender training focuses on increasing individual awareness of gender issues and incorporating gender practices in programs. CEDPA has expanded its programs to include projects promoting increased decision-making power for women regarding their own lives. Family planning and reproductive health projects now include programs designed to increase "women's literacy, credit and income-generation opportunities, and participation in civil society and the political process." Projects address reproductive and human rights, land distribution, economic expansion, credit and savings, and violence against women. Youth programs focus on the changing nature of gender roles, the equal rights of women and girls, and the shared responsibility and mutual respect of the sexes. In the Better Life Options projects, youth of both sexes attend family life and sex education programs. The curriculum "Choose a Future" provides life skills training for young women; a version for young men will be provided in the future. Including men (community health workers and supervisors, educators, trainers, leaders, fathers, and husbands) in the CEDPA programs is essential for the empowerment of women.

  13. Complementing Gender Analysis Methods.

    PubMed

    Kumar, Anant

    2016-01-01

    The existing gender analysis frameworks start with a premise that men and women are equal and should be treated equally. These frameworks give emphasis on equal distribution of resources between men and women and believe that this will bring equality which is not always true. Despite equal distribution of resources, women tend to suffer and experience discrimination in many areas of their lives such as the power to control resources within social relationships, and the need for emotional security and reproductive rights within interpersonal relationships. These frameworks believe that patriarchy as an institution plays an important role in women's oppression, exploitation, and it is a barrier in their empowerment and rights. Thus, some think that by ensuring equal distribution of resources and empowering women economically, institutions like patriarchy can be challenged. These frameworks are based on proposed equality principle which puts men and women in competing roles. Thus, the real equality will never be achieved. Contrary to the existing gender analysis frameworks, the Complementing Gender Analysis framework proposed by the author provides a new approach toward gender analysis which not only recognizes the role of economic empowerment and equal distribution of resources but suggests to incorporate the concept and role of social capital, equity, and doing gender in gender analysis which is based on perceived equity principle, putting men and women in complementing roles that may lead to equality. In this article the author reviews the mainstream gender theories in development from the viewpoint of the complementary roles of gender. This alternative view is argued based on existing literature and an anecdote of observations made by the author. While criticizing the equality theory, the author offers equity theory in resolving the gender conflict by using the concept of social and psychological capital.

  14. Is the gap more than gender? A longitudinal analysis of gender, gender role orientation, and earnings.

    PubMed

    Judge, Timothy A; Livingston, Beth A

    2008-09-01

    This study investigated the relationships among gender, gender role orientation (i.e., attitudes toward the gendered separation of roles at work and at home), and earnings. A multilevel model was conceptualized in which gender role orientation and earnings were within-individual variables that fluctuate over time (although predictors of between-individual differences in gender role orientation were also considered). Results indicated that whereas traditional gender role orientation was positively related to earnings, gender significantly predicted the slope of this relationship: Traditional gender role orientation was strongly positively associated with earnings for men; it was slightly negatively associated with earnings for women. Occupational segregation partly explained these gender differences. Overall, the results suggest that although gender role attitudes are becoming less traditional for men and for women, traditional gender role orientation continues to exacerbate the gender wage gap.

  15. Gender differences in stories of everyday Internet use.

    PubMed

    Dickerson, Suzanne Steffan

    2003-01-01

    This study is a secondary analysis of data collected from four web-based focus groups of nurses and computer scientists who were frequent Internet users. Our aim in this secondary study was to examine gender differences and shared practices in the interpretation of narratives when using this technology. We found that women have different values than men when using the Internet. We can use this information to inform nurses of the gender values that are reflected in Internet usage to increase their understanding of the potential gender stereotyping practices that occur on a medium that is theoretically bias-free.

  16. Gender and violence against people with severe mental illness.

    PubMed

    Khalifeh, Hind; Dean, Kimberlie

    2010-01-01

    Men and women with severe mental illness (SMI) are at significantly increased risk of violent victimisation, but the gender pattern for this has not been systematically examined. In the general population, men are at higher risk of overall and physical victimisation, whilst women are at increased risk of domestic and sexual violence. We re-examined published victimisation studies from a gender perspective, and found that, compared to the general population, women with SMI are at greater excess risk than men, leading to a narrowing in the 'gender gap'. We discuss theoretical explanations for this and implications for prevention and research.

  17. Gender-Blind Sexism and Rape Myth Acceptance.

    PubMed

    Stoll, Laurie Cooper; Lilley, Terry Glenn; Pinter, Kelly

    2017-01-01

    The purpose of this article is to explore whether gender-blind sexism, as an extension of Bonilla-Silva's racialized social system theory, is an appropriate theoretical framework for understanding the creation and continued prevalence of rape myth acceptance. Specifically, we hypothesize that individuals who hold attitudes consistent with the frames of gender-blind sexism are more likely to accept common rape myths. Data for this article come from an online survey administered to the entire undergraduate student body at a large Midwestern institution (N = 1,401). Regression analysis showed strong support for the effects of gender-blind sexism on rape myth acceptance. © The Author(s) 2016.

  18. Space processing of chalcogenide glass

    NASA Technical Reports Server (NTRS)

    Larsen, D. C.; Ali, M. I.

    1977-01-01

    The manner in which the weightless, containerless nature of in-space processing can be successfully utilized to improve the quality of infrared transmitting chalcogenide glasses is determined. The technique of space processing chalcogenide glass was developed, and the process and equipment necessary to do so was defined. Earthbound processing experiments with As2S3 and G28Sb12Se60 glasses were experimented with. Incorporated into these experiments is the use of an acoustic levitation device.

  19. Microsheet Glass In Solar Concentrators

    NASA Technical Reports Server (NTRS)

    Richter, Scott W.

    1993-01-01

    Microsheet glass used as highly protective covering material for developmental concentrating reflectors for solar power systems. Together with other materials, possible to fabricate lightweight, highly reflective, accurate, and long-lived concentrators. Desirable properties include durability and smoothness. Glass not affected by ultraviolet radiation, and not degraded by atomic oxygen, found in low orbits around Earth. Though concentrators intended for use in outer space, noteworthy that terrestrial concentrator fabricated with glass sheet 0.7 mm thick.

  20. PLZT capacitor on glass substrate

    DOEpatents

    Fairchild, Manuel Ray; Taylor, Ralph S.; Berlin, Carl W.; Wong, Celine Wk; Ma, Beihai; Balachandran, Uthamalingam

    2016-03-29

    A lead-lanthanum-zirconium-titanate (PLZT) capacitor on a substrate formed of glass. The first metallization layer is deposited on a top side of the substrate to form a first electrode. The dielectric layer of PLZT is deposited over the first metallization layer. The second metallization layer deposited over the dielectric layer to form a second electrode. The glass substrate is advantageous as glass is compatible with an annealing process used to form the capacitor.

  1. PLZT capacitor on glass substrate

    DOEpatents

    Fairchild, M. Ray; Taylor, Ralph S.; Berlin, Carl W.; Wong, Celine W. K.; Ma, Beihai; Balachandran, Uthamalingam

    2016-01-05

    A lead-lanthanum-zirconium-titanate (PLZT) capacitor on a substrate formed of glass. The first metallization layer is deposited on a top side of the substrate to form a first electrode. The dielectric layer of PLZT is deposited over the first metallization layer. The second metallization layer deposited over the dielectric layer to form a second electrode. The glass substrate is advantageous as glass is compatible with an annealing process used to form the capacitor.

  2. Amplification With Chalcogenide Glass Fiber

    DTIC Science & Technology

    2001-07-12

    34AMPLIFICATION WITH CHALCOGENIDE GLASS FIBER" request for release for publication. REF: (a) NRL Instruction 5510.40C (b) Chapter 6, ONRINST 5870.1C...Serial Number: Patent Application Navy Case Number: 82,848 AMPLIFICATION WITH CFfALCOGENTDE GLASS FIBER Field of the Invention: This invention...pertains to the use of a low phonon energy chalcogenide glass waveguide in conjunction with stimulated Raman scattering to amplify an optical signal

  3. Israeli Kindergarten Children's Gender Constancy for Others' Counter-Stereotypic Toy Play and Appearance: The Role of Sibling Gender and Relative Age

    ERIC Educational Resources Information Center

    Karniol, Rachel

    2009-01-01

    To test divergent theoretical predictions as to the impact of having a younger or older, same-sex sibling or opposite-sex sibling on other gender constancy, Israeli kindergarten children in two-child families responded to a gender constancy task in which a male and female picture target engaged in counter-stereotypic toy play and adopted…

  4. Israeli Kindergarten Children's Gender Constancy for Others' Counter-Stereotypic Toy Play and Appearance: The Role of Sibling Gender and Relative Age

    ERIC Educational Resources Information Center

    Karniol, Rachel

    2009-01-01

    To test divergent theoretical predictions as to the impact of having a younger or older, same-sex sibling or opposite-sex sibling on other gender constancy, Israeli kindergarten children in two-child families responded to a gender constancy task in which a male and female picture target engaged in counter-stereotypic toy play and adopted…

  5. You Can't Get There from Here: Working Women and the Glass Ceiling.

    ERIC Educational Resources Information Center

    Business and Professional Women's Foundation, Washington, DC.

    Over the past two decades women and minorities have made unprecedented strides into the work force, yet discrimination due to gender and race is still a problem. The dearth of women in management is due to the "glass ceiling" phenomenon--the organizational, attitudinal, and societal barriers that effectively keep women and minorities…

  6. Are polymers standard glass-forming systems? The role of intramolecular barriers on the glass-transition phenomena of glass-forming polymers

    NASA Astrophysics Data System (ADS)

    Colmenero, J.

    2015-03-01

    Traditionally, polymer melts have been considered archetypal glass-formers. This has been mainly due to the fact that these systems can easily be obtained as glasses by cooling from the melt, even at low cooling rates. However, the macromolecules, i.e. the structural units of polymer systems in general, are rather different from the standard molecules. They are long objects (‘chains’) made by repetition of a given chemical motif (monomer) and have intra-macromolecular barriers that limit their flexibility. The influence of these properties on, for instance, the glass-transition temperature of polymers, is a topic that has been widely studied by the polymer community almost from the early times of polymer science. However, in the framework of the glass-community, the relevant influence of intra-macromolecular barriers and chain connectivity on glass-transition phenomena of polymers has started to be recognized only recently. The aim of this review is to give an overview and to critically revise the results reported on this topic over the last years. From these results, it seems to be evident that there are two different mechanisms involved in the dynamic arrest in glass-forming polymers: (i) the intermolecular packing effects, which dominate the dynamic arrest of low molecular weight glass-forming systems; and (ii) the effect of intra-macromolecular barriers combined with chain connectivity. It has also been shown that the mode coupling theory (MCT) is a suitable theoretical framework to discuss these questions. The values found for polymers for the central MCT parameter—the so-called λ-exponent—are of the order of 0.9, clearly higher than the standard values (λ ≈ 0.7) found in systems where the dynamic arrest is mainly driven by packing effects (‘standard’ glass-formers). Within the MCT, this is a signature of the presence of two competing mechanisms of dynamic arrest, as it has been observed in short-ranged attractive colloids or two component

  7. POLYESTER GLASS PLASTICS FOR SHIPBUILDING,

    DTIC Science & Technology

    POLYESTER PLASTICS , SHIP HULLS), (*SHIP HULLS, POLYESTER PLASTICS ), GLASS TEXTILES, REINFORCING MATERIALS, SHIP STRUCTURAL COMPONENTS, COMPOSITE MATERIALS, PROCESSING, CHEMISTRY, HANDBOOKS, BINDERS, USSR

  8. THERMAL STABILITY OF GLASS PLASTICS.

    DTIC Science & Technology

    COMPOSITE MATERIALS, THERMAL STABILITY), (* GLASS TEXTILES, THERMAL STABILITY), (*LAMINATED PLASTICS , THERMAL STABILITY), HEATING, COOLING, MECHANICAL PROPERTIES, FATIGUE(MECHANICS), FLEXURAL STRENGTH, THERMAL STRESSES, USSR

  9. Crystallization of copper metaphosphate glass

    NASA Technical Reports Server (NTRS)

    Bae, Byeong-Soo; Weinberg, Michael C.

    1993-01-01

    The effect of the valence state of copper in copper metaphosphate glass on the crystallization behavior and glass transition temperature has been investigated. The crystallization of copper metaphosphate is initiated from the surface and its main crystalline phase is copper metaphosphate (Cu(PO)3),independent of the (Cu sup 2+)/(Cu(total)). However, the crystal morphology, the relative crystallization rates, and their temperature dependences are affected by the (Cu sup 2+)/(Cu (total)) ratio in the glass. On the other hand, the totally oxidized glass crystallizes from all over the surface. The relative crystallization rate of the reduced glass to the totally oxidized glass is large at low temperature, but small at high temperature. The glass transition temperature of the glass increases as the (Cu sup 2+)/(Cu(total)) ratio is raised. It is also found that the atmosphere used during heat treatment does not influence the crystallization of the reduced glass, except for the formation of a very thin CuO surface layer when heated in air.

  10. Glass corrosion in natural environment

    NASA Technical Reports Server (NTRS)

    Thorpe, Arthur N.

    1989-01-01

    A series of studies of the effects of solutes which appear in natural aqueous environments, specifically Mg and Al, under controlled conditions, permit characterization of the retardation of silicate glass leaching in water containing such solutes. In the case of Mg the interaction with the glass appears to consist of exchange with alkali ions present in the glass to a depth of several microns. The effect of Al can be observed at much lower levels, indicating that the mechanism in the case of Al involves irreversible formation of aluminosilicate species at the glass surface.

  11. Crystallization of copper metaphosphate glass

    NASA Technical Reports Server (NTRS)

    Bae, Byeong-Soo; Weinberg, Michael C.

    1993-01-01

    The effect of the valence state of copper in copper metaphosphate glass on the crystallization behavior and glass transition temperature has been investigated. The crystallization of copper metaphosphate is initiated from the surface and its main crystalline phase is copper metaphosphate (Cu(PO)3),independent of the (Cu sup 2+)/(Cu(total)). However, the crystal morphology, the relative crystallization rates, and their temperature dependences are affected by the (Cu sup 2+)/(Cu (total)) ratio in the glass. On the other hand, the totally oxidized glass crystallizes from all over the surface. The relative crystallization rate of the reduced glass to the totally oxidized glass is large at low temperature, but small at high temperature. The glass transition temperature of the glass increases as the (Cu sup 2+)/(Cu(total)) ratio is raised. It is also found that the atmosphere used during heat treatment does not influence the crystallization of the reduced glass, except for the formation of a very thin CuO surface layer when heated in air.

  12. Glass corrosion in natural environments

    NASA Technical Reports Server (NTRS)

    Thorpe, Arthur N.; Barkatt, Aaron

    1992-01-01

    Experiments carried out during the progress period are summarized. Experiments carried out involving glass samples exposed to solutions of Tris have shown the appearance of 'spikes' upon monitoring glass dissolution as a function of time. The periodic 'spikes' observed in Tris-based media were interpreted in terms of cracking due to excessive stress in the surface region of the glass. Studies of the interactions of silicate glasses with metal ions in buffered media were extended to systems containing Al. Caps buffer was used to establish the pH. The procedures used are described and the results are given. Preliminary studies were initiated as to the feasibility of adding a slowly dissolving solid compound of the additive to the glass-water system to maintain a supply of dissolved additive. It appears that several magnesium compounds have a suitable combination of solubility and affinity towards silicate glass surfaces to have a pronounced retarding effect on the extraction of uranium from the glass. These preliminary findings raise the possibility that introducing a magnesium source into geologic repositories for nuclear waste glass in the form of a sparingly soluble Mg-based backfill material may cause a substantial reduction in the extent of long-term glass corrosion. The studies described also provide mechanistic understanding of the roles of various metal solutes in the leachant. Such understanding forms the basis for developing long-term predictions of nuclear waste glass durability under repository conditions. From what is known about natural highly reduced glasses such as tektites, it is clear that iron is dissolved as ferrous iron with little or no ferric iron. The reducing conditions were high enough to cause metallic iron to exsolve out of the glass in the form of submicroscopic spherules. As the nuclear waste glass is much less reduced, a study was initiated on other natural glasses in addition to the nuclear waste glass. Extensive measurements were

  13. [The production of optical glass in France and the experiences of Ruggiero Boscovich for the production of lead glass (Part One)].

    PubMed

    Proverbio, Edoardo

    The experiences that in 1758 led John Dollond to create the first achromatic telescope highlighted the serious difficulties related to the production of lenses with a correction for chromatic aberration. These difficulties were due to the lack of suitable tools for measuring the refraction index and for verifying the curvatures of the lenses of such optical instruments. To this was added what was perhaps the greatest difficulty: i.e., that of acquiring the kinds of glass, the so-called "common" (crown) glass and "lead" (flint) glass, of which the lenses had to be made. If the theoretical works of Alexis Clairaut, of Samuel Klingenstierna, and of Ruggiero Boscovich furnished the theoretical basis for producing such lenses, and subsequently--after Boscovich's discovery of the role of the eyepieces--for creating also achromatic eyepieces, the greatest challenge from the practical point of view was that of the availability of the flint glass. In this first part of the article there is then a study of the numerous attempts and directions pursued by Clairaut and his valid collaborators--Anthéaulme, George father and son, Charles François de l'Etang, and Claude Siméon Passemant--in order to find common glass and lead glass, and to produce the first achromatic lenses and binoculars in France. An analysis follows of the experiences conducted by Boscovich, first in Vienna, and then in Milan and Venice-Murano, addressed to the production of flint glass.

  14. Halide laser glasses

    SciTech Connect

    Weber, M.J.

    1982-01-14

    Energy storage and energy extraction are of prime importance for efficient laser action and are affected by the line strengths and linewidths of optical transitions, excited-state lifetimes, nonradiative decay processes, spectroscopic inhomogeneities, nonlinear refractive index, and damage threshold. These properties are all host dependent. To illustrate this, the spectroscopic properties of Nd/sup 3 +/ have been measured in numerous oxide, oxyhalide, and halide glasses. A table summarizes the reported ranges of stimulated emission cross sections, peak wavelengths, linewidths, and radiative lifetimes associated with the /sup 4/F/sub 3/2/ ..-->.. /sup 4/I/sub 11/2/ lasing transition.

  15. Military Specification, Glass, Optical

    DTIC Science & Technology

    1986-12-05

    PPP-B-621 Visual-spring scale ASTM D3951 Visual 12 MIL-G-174B A - Pin hole aperture B - Movable cross slit D - Diffusion screen LI...for level A except that the barrier bag is omitted. 5.1.3 Commercial. Unless otherwise specified, requirements shall be in accordance with ASTM D3951 ...conforming to PPP-B-636, style optional, special requirements. 5.2.4 Commercial. Preserved glass shall be packed in accordance with ASTM D3951 . 5.3

  16. Glass rupture disk

    DOEpatents

    Glass, S. Jill; Nicolaysen, Scott D.; Beauchamp, Edwin K.

    2002-01-01

    A frangible rupture disk and mounting apparatus for use in blocking fluid flow, generally in a fluid conducting conduit such as a well casing, a well tubing string or other conduits within subterranean boreholes. The disk can also be utilized in above-surface pipes or tanks where temporary and controllable fluid blockage is required. The frangible rupture disk is made from a pre-stressed glass with controllable rupture properties wherein the strength distribution has a standard deviation less than approximately 5% from the mean strength. The frangible rupture disk has controllable operating pressures and rupture pressures.

  17. Solarization of heliostat glasses

    NASA Astrophysics Data System (ADS)

    Vitko, J., Jr.; Shelby, J. E.

    1980-09-01

    A solar-induced decrease in Fe(2+) absorption was observed in heliostat glasses from the solar furnace at Odeillo, France. This decrease occurs throughout the sample and is of sufficient magnitude to result in an increase of 2.5% in solar transmittance in a period of nine years. Optical and ESR studies did not detect a corresponding increase in Fe(3+) concentration. The effect of these results on a microscopic model for the observed solarization is discussed. Solar simulation studies produced changes of magnitude and sign similar to those observed in the field exposed samples, and offer attractive means for screening samples for solarization tendencies.

  18. Compositional threshold for Nuclear Waste Glass Durability

    SciTech Connect

    Kruger, Albert A.; Farooqi, Rahmatullah; Hrma, Pavel R.

    2013-04-24

    Within the composition space of glasses, a distinct threshold appears to exist that separates "good" glasses, i.e., those which are sufficiently durable, from "bad" glasses of a low durability. The objective of our research is to clarify the origin of this threshold by exploring the relationship between glass composition, glass structure and chemical durability around the threshold region.

  19. Method for heating a glass sheet

    DOEpatents

    Boaz, Premakaran Tucker

    1998-01-01

    A method for heating a glass sheet includes the steps of heating a glass sheet to a first predetermined temperature and applying microwave energy to the glass sheet to heat the glass sheet to at least a second predetermined temperature to allow the glass sheet to be formed.

  20. Method for heating a glass sheet

    DOEpatents

    Boaz, P.T.

    1998-07-21

    A method for heating a glass sheet includes the steps of heating a glass sheet to a first predetermined temperature and applying microwave energy to the glass sheet to heat the glass sheet to at least a second predetermined temperature to allow the glass sheet to be formed. 5 figs.

  1. Barium-borate-flyash glasses: As radiation shielding materials

    NASA Astrophysics Data System (ADS)

    Singh, Sukhpal; Kumar, Ashok; Singh, Devinder; Thind, Kulwant Singh; Mudahar, Gurmel S.

    2008-01-01

    The attenuation coefficients of barium-borate-flyash glasses have been measured for γ-ray photon energies of 356, 662, 1173 and 1332 keV using narrow beam transmission geometry. The photon beam was highly collimated and overall scatter acceptance angle was less than 3°. Our results have an uncertainty of less than 3%. These coefficients were then used to obtain the values of mean free path (mfp), effective atomic number and electron density. Good agreements have been observed between experimental and theoretical values of these parameters. From the studies of the obtained results it is reported here that from the shielding point of view the barium-borate-flyash glasses are better shields to γ-radiations in comparison to the standard radiation shielding concretes and also to the ordinary barium-borate glasses.

  2. The Spin Glass-Kondo Competition in Disordered Cerium Systems

    NASA Astrophysics Data System (ADS)

    Magalhaes, S. G.; Zimmer, F.; Coqblin, B.

    2013-10-01

    We discuss the competition between the Kondo effect, the spin glass state and a magnetic order observed in disordered Cerium systems. We present firstly the experimental situation of disordered alloys such as CeNi1 - xCux and then the different theoretical approaches based on the Kondo lattice model, with different descriptions of the intersite exchange interaction for the spin glass. After the gaussian approach of the Sherrington-Kirkpatrick model, we discuss the Mattis and the van Hemmen models. Then, we present simple cluster calculations in order to describe the percolative evolution of the clusters from the cluster spin glass to the inhomogeneous ferromagnetic order recently observed in CeNi1 - xCux disordered alloys and finally we discuss the effect of random and transverse magnetic field.

  3. Echoes of the Glass Transition in Athermal Soft Spheres

    NASA Astrophysics Data System (ADS)

    Morse, Peter K.; Corwin, Eric I.

    2017-09-01

    Recent theoretical advances have led to the creation of a unified phase diagram for the thermal glass and athermal jamming transitions. This diagram makes clear that, while related, the mode-coupling—or dynamic—glass transition is distinct from the jamming transition, occurring at a finite temperature and significantly lower density than the jamming transition. Nonetheless, we demonstrate a prejamming transition in athermal frictionless spheres which occurs at the same density as the mode-coupling transition and is marked by percolating clusters of locally rigid particles. At this density in both the thermal and athermal systems, individual motions of an extensive number of particles become constrained, such that only collective motion is possible. This transition, which is well below jamming, exactly matches the definition of collective behavior at the dynamical transition of glasses. Thus, we reveal that the genesis of rigidity in both thermal and athermal systems is governed by the same underlying topological transition in their shared configuration space.

  4. Luminescence quenching of Dy3+ ions in lead bismuthate glasses

    NASA Astrophysics Data System (ADS)

    Pisarski, Wojciech A.; Pisarska, Joanna; Lisiecki, Radosław; Dominiak-Dzik, Grażyna; Ryba-Romanowski, Witold

    2012-04-01

    Luminescence of lead bismuthate glasses PbO-Bi2O3-Ga2O3 containing Dy3+ ions has been studied. Two overlapping luminescence bands corresponding to 3P1-1S0 transition of Bi3+ and 4F9/2 -6H13/2 transition of Dy3+ were detected under 480 nm excitation. Comparison of luminescence features for the system under study to those reported for dysprosium-doped lead borate glass PbO-B2O3-Ga2O3 indicates that the luminescence of Dy3+ is efficiently quenched by Bi3+ ions. Analysis of luminescence dynamics implies that the excitation energy transfer from Dy3+ to Bi3+ is nonradiative. The theoretical calculations using Inokuti-Hirayama model confirm strong luminescence of Dy3+ ions in lead bismuthate glasses.

  5. Specific heat anomaly in relaxor ferroelectrics and dipolar glasses

    NASA Astrophysics Data System (ADS)

    Kutnjak, Z.; Pirc, R.

    2017-03-01

    The temperature and electric field dependence of the specific heat of relaxor ferroelectrics and dipolar glasses is investigated by means of a Landau-type theoretical model. It is shown that the dipolar specific heat, which is due to the randomly interacting polar nanoregions in relaxors and electric dipoles in dipolar glasses, is negative in a temperature region below the permittivity maximum. Also, it follows that for sufficiently low values of the field, where the induced polarization shows a quasi linear field dependence, the dipolar specific heat is proportional to the second temperature derivative of the dielectric polarization. This quantity can be extracted from the experimental temperature profile of the polarization, thus enabling an indirect experimental estimate of the negative specific heat, which is demonstrated for a set of representative relaxor and dipolar glass systems.

  6. Critical droplet theory explains the glass formability of aqueous solutions.

    PubMed

    Warkentin, Matthew; Sethna, James P; Thorne, Robert E

    2013-01-04

    When pure water is cooled at ~10(6) K / s, it forms an amorphous solid (glass) instead of the more familiar crystalline phase. The presence of solutes can reduce this required (or "critical") cooling rate by orders of magnitude. Here, we present critical cooling rates for a variety of solutes as a function of concentration and a theoretical framework for understanding these rates. For all solutes tested, the critical cooling rate is an exponential function of concentration. The exponential's characteristic concentration for each solute correlates with the solute's Stokes radius. A modification of critical droplet theory relates the characteristic concentration to the solute radius and the critical nucleation radius of ice in pure water. This simple theory of ice nucleation and glass formability in aqueous solutions has consequences for general glass-forming systems, and in cryobiology, cloud physics, and climate modeling.

  7. Examination of glass-silicon and glass-glass bonding techniques for microfluidic systems

    SciTech Connect

    Raley, N.F.; Davidson, J.C.; Balch, J.W.

    1995-10-23

    We report here on the results of experiments concerning particular bonding processes potentially useful for ultimate miniaturization of microfluidic systems. Direct anodic bonding of continuous thin pyrex glass of 250 {mu}m thickness to silicon substrates gives multiple, large voids in the glass. Etchback of thick glass of 1200 {mu}m thickness bonded to silicon substrates gives thin continuous glass layers of 189 {mu}m thickness without voids over areas of 5 cm {times} 12 cm. Glass was also successfully bonded to glass by thermal bonding at 800{degrees}C over a 5 cm {times} 7 cm area. Anticipated applications include microfabricated DNA sequencing, flow injection analysis, and liquid and gas chromatography microinstruments.

  8. Gender Attribution and Gender Agreement in French Williams Syndrome

    ERIC Educational Resources Information Center

    Boloh, Yves; Ibernon, Laure; Royer, Stephanie; Escudier, Frederique; Danillon, Aurelia

    2009-01-01

    Previous studies on grammatical gender in French individuals with Williams syndrome (WS) have led to conflicting findings and interpretations regarding keys abilities--gender attribution and gender agreement. New production data from a larger SW sample (N = 24) showed that gender attribution scores in SW participants exactly mirrored those of…

  9. Gender Attribution and Gender Agreement in French Williams Syndrome

    ERIC Educational Resources Information Center

    Boloh, Yves; Ibernon, Laure; Royer, Stephanie; Escudier, Frederique; Danillon, Aurelia

    2009-01-01

    Previous studies on grammatical gender in French individuals with Williams syndrome (WS) have led to conflicting findings and interpretations regarding keys abilities--gender attribution and gender agreement. New production data from a larger SW sample (N = 24) showed that gender attribution scores in SW participants exactly mirrored those of…

  10. Grammatical Gender vs. Natural Gender in French Williams Syndrome

    ERIC Educational Resources Information Center

    Ibernon, Laure; Boloh, Yves

    2010-01-01

    This article reports grammatical gender attribution scores in French Williams participants (N = 28, mean chronological age = 15.1) in an experiment similar to the classic one from Karmiloff-Smith (1979) where grammatical gender was pitted against natural gender. WS participants massively opted for the masculine gender as the default one, just as…

  11. POROUS WALL, HOLLOW GLASS MICROSPHERES

    SciTech Connect

    Sexton, W.

    2012-06-30

    Hollow Glass Microspheres (HGM) is not a new technology. All one has to do is go to the internet and Google{trademark} HGM. Anyone can buy HGM and they have a wide variety of uses. HGM are usually between 1 to 100 microns in diameter, although their size can range from 100 nanometers to 5 millimeters in diameter. HGM are used as lightweight filler in composite materials such as syntactic foam and lightweight concrete. In 1968 a patent was issued to W. Beck of the 3M{trademark} Company for 'Glass Bubbles Prepared by Reheating Solid Glass Particles'. In 1983 P. Howell was issued a patent for 'Glass Bubbles of Increased Collapse Strength' and in 1988 H. Marshall was issued a patent for 'Glass Microbubbles'. Now Google{trademark}, Porous Wall, Hollow Glass Microspheres (PW-HGMs), the key words here are Porous Wall. Almost every article has its beginning with the research done at the Savannah River National Laboratory (SRNL). The Savannah River Site (SRS) where SRNL is located has a long and successful history of working with hydrogen and its isotopes for national security, energy, waste management and environmental remediation applications. This includes more than 30 years of experience developing, processing, and implementing special ceramics, including glasses for a variety of Department of Energy (DOE) missions. In the case of glasses, SRS and SRNL have been involved in both the science and engineering of vitreous or glass based systems. As a part of this glass experience and expertise, SRNL has developed a number of niches in the glass arena, one of which is the development of porous glass systems for a variety of applications. These porous glass systems include sol gel glasses, which include both xerogels and aerogels, as well as phase separated glass compositions, that can be subsequently treated to produce another unique type of porosity within the glass forms. The porous glasses can increase the surface area compared to 'normal glasses of a 1 to 2 order of

  12. Analyzing the glass ceiling effect among radiologic technologists.

    PubMed

    Belinsky, Susan B; Blagg, James D

    2011-01-01

    The literature has suggested that advancement within politics, academia and the health professions is influenced by gender. Purpose The authors conducted a survey to determine whether advancement was equal by gender in the radiologic science disciplines of nuclear medicine technology, radiation therapy and radiography. The survey was mailed to 900 subjects, 300 from each discipline. The discipline groups were further stratified by initial year of American Registry of Radiologic Technology certification; the authors selected 100 subjects from each discipline who initially were certified in 1978, 100 in 1988 and 100 in 1998. Approximately 33% of those selected responded. The findings of the study provided no evidence that men are promoted differentially than women. Women perceived that men were paid more for the same work. It appears that gender bias is pervasive outside of promotion decisions and, indeed, that some illegal actions (eg, sexual harassment, inappropriate gender-related interview questions) take place in radiologic science clinical settings. It is hoped that this study will set a baseline for future research on whether there is a glass ceiling effect in radiologic clinical practice and stimulate discussion of the importance of equal opportunity regardless of gender.

  13. Evidence that gendered wording in job advertisements exists and sustains gender inequality.

    PubMed

    Gaucher, Danielle; Friesen, Justin; Kay, Aaron C

    2011-07-01

    Social dominance theory (Sidanius & Pratto, 1999) contends that institutional-level mechanisms exist that reinforce and perpetuate existing group-based inequalities, but very few such mechanisms have been empirically demonstrated. We propose that gendered wording (i.e., masculine- and feminine-themed words, such as those associated with gender stereotypes) may be a heretofore unacknowledged, institutional-level mechanism of inequality maintenance. Employing both archival and experimental analyses, the present research demonstrates that gendered wording commonly employed in job recruitment materials can maintain gender inequality in traditionally male-dominated occupations. Studies 1 and 2 demonstrated the existence of subtle but systematic wording differences within a randomly sampled set of job advertisements. Results indicated that job advertisements for male-dominated areas employed greater masculine wording (i.e., words associated with male stereotypes, such as leader, competitive, dominant) than advertisements within female-dominated areas. No difference in the presence of feminine wording (i.e., words associated with female stereotypes, such as support, understand, interpersonal) emerged across male- and female-dominated areas. Next, the consequences of highly masculine wording were tested across 3 experimental studies. When job advertisements were constructed to include more masculine than feminine wording, participants perceived more men within these occupations (Study 3), and importantly, women found these jobs less appealing (Studies 4 and 5). Results confirmed that perceptions of belongingness (but not perceived skills) mediated the effect of gendered wording on job appeal (Study 5). The function of gendered wording in maintaining traditional gender divisions, implications for gender parity, and theoretical models of inequality are discussed. PsycINFO Database Record (c) 2011 APA, all rights reserved.

  14. Gender Disparities in Osteoporosis

    PubMed Central

    Alswat, Khaled A.

    2017-01-01

    Osteoporosis is a growing health concern worldwide and its complications are as prevalent as other common chronic disease complications such as hypertension and diabetes. In this review, we will discuss the role of gender in osteoporosis, especially related to peak bone mass and maturation, rate of annual bone loss, screening, prevalence of osteoporosis and its related fractures, mortality after osteoporosis-related fracture, fracture risk predication using different technologies and the impact of gender on osteoporosis management. PMID:28392857

  15. Quinary metallic glass alloys

    DOEpatents

    Lin, X.; Johnson, W.L.

    1998-04-07

    At least quinary alloys form metallic glass upon cooling below the glass transition temperature at a rate less than 10{sup 3}K/s. Such alloys comprise zirconium and/or hafnium in the range of 45 to 65 atomic percent, titanium and/or niobium in the range of 4 to 7.5 atomic percent, and aluminum and/or zinc in the range of 5 to 15 atomic percent. The balance of the alloy compositions comprise copper, iron, and cobalt and/or nickel. The composition is constrained such that the atomic percentage of iron is less than 10 percent. Further, the ratio of copper to nickel and/or cobalt is in the range of from 1:2 to 2:1. The alloy composition formula is: (Zr,Hf){sub a}(Al,Zn){sub b}(Ti,Nb){sub c}(Cu{sub x}Fe{sub y}(Ni,Co){sub z}){sub d} wherein the constraints upon the formula are: a ranges from 45 to 65 atomic percent, b ranges from 5 to 15 atomic percent, c ranges from 4 to 7.5 atomic percent, d comprises the balance, d{hor_ellipsis}y is less than 10 atomic percent, and x/z ranges from 0.5 to 2.

  16. Quinary metallic glass alloys

    DOEpatents

    Lin, Xianghong; Johnson, William L.

    1998-01-01

    At least quinary alloys form metallic glass upon cooling below the glass transition temperature at a rate less than 10.sup.3 K/s. Such alloys comprise zirconium and/or hafnium in the range of 45 to 65 atomic percent, titanium and/or niobium in the range of 4 to 7.5 atomic percent, and aluminum and/or zinc in the range of 5 to 15 atomic percent. The balance of the alloy compositions comprise copper, iron, and cobalt and/or nickel. The composition is constrained such that the atomic percentage of iron is less than 10 percent. Further, the ratio of copper to nickel and/or cobalt is in the range of from 1:2 to 2:1. The alloy composition formula is: (Zr,Hf).sub.a (Al,Zn).sub.b (Ti,Nb).sub.c (Cu.sub.x Fe.sub.y (Ni,Co).sub.z).sub.d wherein the constraints upon the formula are: a ranges from 45 to 65 atomic percent, b ranges from 5 to 15 atomic percent, c ranges from 4 to 7.5 atomic percent, d comprises the balance, d.multidot.y is less than 10 atomic percent, and x/z ranges from 0.5 to 2.

  17. Spheroidization of glass powders for glass ionomer cements.

    PubMed

    Gu, Y W; Yap, A U J; Cheang, P; Kumar, R

    2004-08-01

    Commercial angular glass powders were spheroidized using both the flame spraying and inductively coupled radio frequency plasma spraying techniques. Spherical powders with different particle size distributions were obtained after spheroidization. The effects of spherical glass powders on the mechanical properties of glass ionomer cements (GICs) were investigated. Results showed that the particle size distribution of the glass powders had a significant influence on the mechanical properties of GICs. Powders with a bimodal particle size distribution ensured a high packing density of glass ionomer cements, giving relatively high mechanical properties of GICs. GICs prepared by flame-spheroidized powders showed low strength values due to the loss of fine particles during flame spraying, leading to a low packing density and few metal ions reacting with polyacrylic acid to form cross-linking. GICs prepared by the nano-sized powders showed low strength because of the low bulk density of the nano-sized powders and hence low powder/liquid ratio of GICs.

  18. Mechanical failure and glass transition in metallic glasses

    SciTech Connect

    Egami, Takeshi

    2011-01-01

    The current majority view on the phenomenon of mechanical failure in metallic glasses appears to be that it is caused by the activity of some structural defects, such as free-volumes or shear transformation zones, and the concentration of such defects is small, only of the order of 1%. However, the recent results compel us to revise this view. Through molecular dynamics simulation it has been shown that mechanical failure is the stress-induced glass transition. According to our theory the concentration of the liquid-like sites (defects) is well over 20% at the glass transition. We suggest that the defect concentration in metallic glasses is actually very high, and percolation of such defects causes atomic avalanche and mechanical failure. In this article we discuss the glass transition, mechanical failure and viscosity from such a point of view.

  19. Gender dysphoria in childhood.

    PubMed

    Ristori, Jiska; Steensma, Thomas D

    2016-01-01

    Gender dysphoria (GD) in childhood is a complex phenomenon characterized by clinically significant distress due to the incongruence between assigned gender at birth and experienced gender. The clinical presentation of children who present with gender identity issues can be highly variable; the psychosexual development and future psychosexual outcome can be unclear, and consensus about the best clinical practice is currently under debate. In this paper a clinical picture is provided of children who are referred to gender identity clinics. The clinical criteria are described including what is known about the prevalence of childhood GD. In addition, an overview is presented of the literature on the psychological functioning of children with GD, the current knowledge on the psychosexual development and factors associated with the persistence of GD, and explanatory models for psychopathology in children with GD together with other co-existing problems that are characteristic for children referred for their gender. In light of this, currently used treatment and counselling approaches are summarized and discussed, including the integration of the literature detailed above.

  20. Signature of a Type-A Glass Transition and Intrinsic Confinement Effects in a Binary Glass-Forming System

    NASA Astrophysics Data System (ADS)

    Blochowicz, Thomas; Schramm, Sebastian; Lusceac, Sorin; Vogel, Michael; Stühn, Bernd; Gutfreund, Philipp; Frick, Bernhard

    2012-07-01

    We study dynamically highly asymmetric binary mixtures comprised of small methyl tetrahydrofuran (MTHF) molecules and polystyrene. Combined use of dielectric spectroscopy, H2 nuclear magnetic resonance, incoherent quasielastic neutron scattering, and depolarized dynamic light scattering allows us to selectively probe the dynamics of the components in a broad dynamic range. It turns out that the mixtures exhibit two glass transitions in a wide concentration range although being fully miscible on a macroscopic scale. In between both glass transition temperatures, the dynamics of the small molecules show strong confinement effects, e.g., a crossover from Vogel-Fulcher to Arrhenius behavior of the time constants. Moreover, the dynamical behavior of small molecules close to the slow matrix is consistent with mode coupling theory predictions for a type-A glass transition, which was expected from recent theoretical and simulation studies in comparable systems.

  1. Gender equality and gender differences: parenting, habitus, and embodiment (the 2008 Porter lecture).

    PubMed

    Doucet, Andrea

    2009-05-01

    Drawing on a four-year research project on Canadian primary caregiving fathers, as well two recent projects on the first year of parenting, this article highlights several theoretical and substantive issues in the study of gender equality and gender differences in parenting. First, I call for shifts from a focus on domestic tasks toward domestic and community-based responsibilities. Second, I argue that the political terrain underpinning the study of mothering and fathering calls for clarity on how researchers interpret the constant interplay between equality and differences. Third, while there has been some change over time, parental responsibilities remain gendered because they are deeply rooted in habitus and embodiment across specific spatial and temporal contexts.

  2. Gender Asymmetries in Today's Russia

    ERIC Educational Resources Information Center

    Rimashevskaia, N. M.

    2011-01-01

    There can be no doubt that gender attitudes and the gender stereotypes formed on their basis have a deep-rooted social character. This stems unequivocally from the parallels of development of social processes and gender models. The ideology of gender began to flourish in Russia along with perestroika, an ideology that in the past quarter-century…

  3. Feminism, Budgeting and Gender Justice

    ERIC Educational Resources Information Center

    Misra, S. N.; Ghadai, Sanjaya Kumar

    2017-01-01

    The Fourth Conference on Women at Beijing (1995) underlined the importance of gender mainstreaming; spurring India to provide for separate Gender Budgeting in 2005-06. The Constitution tries to make fine balance between right to equality and positive discrimination for promoting gender justice in India. Yet high levels of Gender Inequality Index…

  4. Gendered Language in Interactive Discourse

    ERIC Educational Resources Information Center

    Hussey, Karen A.; Katz, Albert N.; Leith, Scott A.

    2015-01-01

    Over two studies, we examined the nature of gendered language in interactive discourse. In the first study, we analyzed gendered language from a chat corpus to see whether tokens of gendered language proposed in the gender-as-culture hypothesis (Maltz and Borker in "Language and social identity." Cambridge University Press, Cambridge, pp…

  5. Gendered Language in Interactive Discourse

    ERIC Educational Resources Information Center

    Hussey, Karen A.; Katz, Albert N.; Leith, Scott A.

    2015-01-01

    Over two studies, we examined the nature of gendered language in interactive discourse. In the first study, we analyzed gendered language from a chat corpus to see whether tokens of gendered language proposed in the gender-as-culture hypothesis (Maltz and Borker in "Language and social identity." Cambridge University Press, Cambridge, pp…

  6. Glasses in the D'Orbigny Angrite

    NASA Astrophysics Data System (ADS)

    Varela, M. E.; Kurat, G.; Brandstätter, F.; Bonnin-Mosbah, M.; Metrich, N.

    2001-03-01

    The D'Orbigny angrite contains abundant glasses, a phase which has not been previously reported from any other angrite. Glasses fill in part open druses and intersticial spaces between major silicates, or occur as glass inclusions in olivine.

  7. Scaling for hard-sphere colloidal glasses near jamming

    NASA Astrophysics Data System (ADS)

    Zargar, Rojman; DeGiuli, Eric; Bonn, Daniel

    2016-12-01

    Hard-sphere colloids are model systems in which to study the glass transition and universal properties of amorphous solids. Using covariance matrix analysis to determine the vibrational modes, we experimentally measure here the scaling behavior of the density of states, shear modulus, and mean-squared displacement (MSD) in a hard-sphere colloidal glass. Scaling the frequency with the boson-peak frequency, we find that the density of states at different volume fractions all collapse on a single master curve, which obeys a power law in terms of the scaled frequency. Below the boson peak, the exponent is consistent with theoretical results obtained by real-space and phase-space approaches to understanding amorphous solids. We find that the shear modulus and the MSD are nearly inversely proportional, and show a singular power-law dependence on the distance from random close packing. Our results are in very good agreement with the theoretical predictions.

  8. An automated pipette puller for fabrication of glass micropipettes.

    PubMed

    Tamizhanban, R; Sreejith, K R; Jayanth, G R

    2014-05-01

    Glass micropipettes are versatile probing tools for performing micro- and nano-manipulation tasks. This paper presents the design and development of an automated pipette puller system for fabrication of glass micropipettes. The pipette puller employs a new strategy for fabrication of micropipettes that enables achieving independent control of their taper, tip diameter, and bend-angle, and also facilitates theoretical derivation of simple, approximate relationships between the pipette shape and the pulling parameters. Subsequently, the design and fabrication of the pipette puller is described, which include that of the pipette heating system, the mechanical motion stages, and the control electronics of the pipette puller. The fabricated pipette puller is experimentally evaluated to demonstrate control of the taper, tip diameter, and the bend-angle of the micropipette. Further, the dependence of the taper and tip diameter on the pulling parameters is evaluated and is shown to be in alignment with the proposed theoretical relationships.

  9. An automated pipette puller for fabrication of glass micropipettes

    NASA Astrophysics Data System (ADS)

    Tamizhanban, R.; Sreejith, K. R.; Jayanth, G. R.

    2014-05-01

    Glass micropipettes are versatile probing tools for performing micro- and nano-manipulation tasks. This paper presents the design and development of an automated pipette puller system for fabrication of glass micropipettes. The pipette puller employs a new strategy for fabrication of micropipettes that enables achieving independent control of their taper, tip diameter, and bend-angle, and also facilitates theoretical derivation of simple, approximate relationships between the pipette shape and the pulling parameters. Subsequently, the design and fabrication of the pipette puller is described, which include that of the pipette heating system, the mechanical motion stages, and the control electronics of the pipette puller. The fabricated pipette puller is experimentally evaluated to demonstrate control of the taper, tip diameter, and the bend-angle of the micropipette. Further, the dependence of the taper and tip diameter on the pulling parameters is evaluated and is shown to be in alignment with the proposed theoretical relationships.

  10. Degradable borate glass polyalkenoate cements.

    PubMed

    Shen, L; Coughlan, A; Towler, M; Hall, M

    2014-04-01

    Glass polyalkenoate cements (GPCs) containing aluminum-free borate glasses having the general composition Ag2O-Na2O-CaO-SrO-ZnO-TiO2-B2O3 were evaluated in this work. An initial screening study of sixteen compositions was used to identify regions of glass formation and cement compositions with promising rheological properties. The results of the screening study were used to develop four model borate glass compositions for further study. A second round of rheological experiments was used to identify a preferred GPC formulation for each model glass composition. The model borate glasses containing higher levels of TiO2 (7.5 mol %) tended to have longer working times and shorter setting times. Dissolution behavior of the four model GPC formulations was evaluated by measuring ion release profiles as a function of time. All four GPC formulations showed evidence of incongruent dissolution behavior when considering the relative release profiles of sodium and boron, although the exact dissolution profile of the glass was presumably obscured by the polymeric cement matrix. Compression testing was undertaken to evaluate cement strength over time during immersion in water. The cements containing the borate glass with 7.5 mol % TiO2 had the highest initial compressive strength, ranging between 20 and 30 MPa. No beneficial aging effect was observed-instead, the strength of all four model GPC formulations was found to degrade with time.

  11. Training Guidelines: Glass Furnace Operators.

    ERIC Educational Resources Information Center

    Ceramics, Glass, and Mineral Products Industry Training Board, Harrow (England).

    Technological development in the glass industry is constantly directed towards producing high quality glass at low operating costs. Particularly, changes have taken place in melting methods which mean that the modern furnace operator has greater responsibilities than any of his predecessors. The complexity of control systems, melting rates, tank…

  12. Space processing of chalcogenide glass

    NASA Technical Reports Server (NTRS)

    Firestone, R. F.; Schramm, S. W.

    1978-01-01

    A program was conducted to develop the technique of space processing for chalcogenide glass, and to define the process and equipment necessary. In the course of this program, successful long term levitation of objects in a 1-g environment was achieved. Glass beads 4 mm diameter were containerless melted and fused together.

  13. Making a Better Beer Glass.

    ERIC Educational Resources Information Center

    Hoffer, Alan R.

    1982-01-01

    A class activity is detailed in which alternative designs for glasses are examined. The goal is to design a glass which is built tilted, so that beer can be poured in without creating a foam problem. The activity is viewed as one leading to interesting questions. (MP)

  14. Holder for rotating glass body

    DOEpatents

    Kolleck, Floyd W.

    1978-04-04

    A device is provided for holding and centering a rotating glass body such as a rod or tube. The device includes a tubular tip holder which may be held in a lathe chuck. The device can utilize a variety of centering tips each adapted for a particular configuration, such as a glass O-ring joint or semi-ball joint.

  15. Method of determining glass durability

    DOEpatents

    Jantzen, C.M.; Pickett, J.B.; Brown, K.G.; Edwards, T.B.

    1998-12-08

    A process is described for determining one or more leachate concentrations of one or more components of a glass composition in an aqueous solution of the glass composition by identifying the components of the glass composition, including associated oxides, determining a preliminary glass dissolution estimator, {Delta}G{sub p}, based upon the free energies of hydration for the component reactant species, determining an accelerated glass dissolution function, {Delta}G{sub a}, based upon the free energy associated with weak acid dissociation, {Delta}G{sub a}{sup WA}, and accelerated matrix dissolution at high pH, {Delta}G{sub a}{sup SB} associated with solution strong base formation, and determining a final hydration free energy, {Delta}G{sub f}. This final hydration free energy is then used to determine leachate concentrations for elements of interest using a regression analysis and the formula log{sub 10}(N C{sub i}(g/L))=a{sub i} + b{sub i}{Delta}G{sub f}. The present invention also includes a method to determine whether a particular glass to be produced will be homogeneous or phase separated. The present invention is also directed to methods of monitoring and controlling processes for making glass using these determinations to modify the feedstock materials until a desired glass durability and homogeneity is obtained. 4 figs.

  16. Method of determining glass durability

    DOEpatents

    Jantzen, Carol Maryanne; Pickett, John Butler; Brown, Kevin George; Edwards, Thomas Barry

    1998-01-01

    A process for determining one or more leachate concentrations of one or more components of a glass composition in an aqueous solution of the glass composition by identifying the components of the glass composition, including associated oxides, determining a preliminary glass dissolution estimator, .DELTA.G.sub.p, based upon the free energies of hydration for the component reactant species, determining an accelerated glass dissolution function, .DELTA.G.sub.a, based upon the free energy associated with weak acid dissociation, .DELTA.G.sub.a.sup.WA, and accelerated matrix dissolution at high pH, .DELTA.G.sub.a.sup.SB associated with solution strong base formation, and determining a final hydration free energy, .DELTA.G.sub.f. This final hydration free energy is then used to determine leachate concentrations for elements of interest using a regression analysis and the formula log.sub.10 (N C.sub.i (g/L))=a.sub.i +b.sub.i .DELTA.G.sub.f. The present invention also includes a method to determine whether a particular glass to be produced will be homogeneous or phase separated. The present invention is also directed to methods of monitoring and controlling processes for making glass using these determinations to modify the feedstock materials until a desired glass durability and homogeneity is obtained.

  17. Refractory Glass Seals for SOFC

    SciTech Connect

    Chou, Y. S.; Stevenson, Jeffry W.

    2011-07-01

    One of the critical challenges facing planar solid oxide fuel cell (SOFC) technology is the need for reliable sealing technology. Seals must exhibit long-term stability and mechanical integrity in the high temperature SOFC environment during normal and transient operation. Several different approaches for sealing SOFC stacks are under development, including glass or glass-ceramic seals, metallic brazes, and compressive seals. Among glass seals, rigid glass-ceramics, self-healing glass, and composite glass approaches have been investigated under the SECA Core Technology Program. The U.S. Department of Energy's Pacific Northwest National Laboratory (PNNL) has developed the refractory glass approach in light of the fact that higher sealing temperatures (e.g., 930-1000 degrees C) may enhance the ultimate in-service bulk strength and electrical conductivity of contact materials, as well as the bonding strength between contact materials and adjacent SOFC components, such as interconnect coatings and electrodes. This report summarizes the thermal, chemical, mechanical, and electrical properties of the refractory sealing glass.

  18. International Congress on Glass XII

    SciTech Connect

    Doremus, R H; LaCourse, W C; Mackenzie, J D; Varner, J R; Wolf, W W

    1980-01-01

    A total of 158 papers are included under nine headings: structure and glass formation; optical properties; electrical and magnetic properties; mechanical properties and relaxation; mass transport; chemical durability and surfaces; nucleation; crystallization; and glass ceramics; processing; and automatic controls. Separate abstracts were prepared for eight papers; four of the remaining papers had been processed previously for the data base. (DLC)

  19. Consensus theoretic classification methods

    NASA Technical Reports Server (NTRS)

    Benediktsson, Jon A.; Swain, Philip H.

    1992-01-01

    Consensus theory is adopted as a means of classifying geographic data from multiple sources. The foundations and usefulness of different consensus theoretic methods are discussed in conjunction with pattern recognition. Weight selections for different data sources are considered and modeling of non-Gaussian data is investigated. The application of consensus theory in pattern recognition is tested on two data sets: 1) multisource remote sensing and geographic data and 2) very-high-dimensional remote sensing data. The results obtained using consensus theoretic methods are found to compare favorably with those obtained using well-known pattern recognition methods. The consensus theoretic methods can be applied in cases where the Gaussian maximum likelihood method cannot. Also, the consensus theoretic methods are computationally less demanding than the Gaussian maximum likelihood method and provide a means for weighting data sources differently.

  20. A New Theoretical Psychology?

    ERIC Educational Resources Information Center

    Longuet-Higgins, H. C.

    1982-01-01

    It is suggested that the study of artificial intelligence can provide ways of thinking about the human mind that are potentially valuable in formulating cognitive theories. Theoretical psychology is proposed as an appropriate classification for this branch of theory. (MSE)

  1. Phase separation of cesium from lead borosilicate glass by heat treatment under a reducing atmosphere.

    PubMed

    Xu, Zhanglian; Okada, Takashi; Nishimura, Fumihiro; Yonezawa, Susumu

    2016-11-05

    A phase-separation technique for removing sodium from glass using a heat-treatment method under a reducing atmosphere was previously developed for sodium recovery from waste glass. In this study, this technique was applied to cesium-containing lead borosilicate glass to concentrate the cesium in phase-separated sodium-rich materials for efficient cesium extraction. The theoretical phase-separation temperature of the sodium-rich phase was simulated by thermodynamic equilibrium calculations and was predicted to occur below 700°C for lead borosilicate glass. Experimentally, a simulated lead borosilicate glass was melted at 1000°C and subsequently annealed below 700°C under a CO-containing reducing atmosphere. The phase separation of cesium was found to occur with sodium enrichment on the glass surface that was in contact with the gas phase, promoting cesium extraction from the treated glass using water. The cesium extraction efficiency was affected by the surface area of the treated glass that was in contact with water, and under the examined conditions, the cesium extraction efficiency was up to 66%. Phase separation using reductive heat treatment, combined with a water leaching technique, is suggested to be effective for extracting cesium incorporated in borosilicate glass waste.

  2. Mixed alkali effect in glasses containing MnO{sub 2}

    SciTech Connect

    Reddy, M. Sudhakara; Rajiv, Asha; Veeranna Gowda, V. C.; Chakradhar, R. P. S.; Reddy, C. Narayana

    2013-02-05

    Glass systems of the composition xLi{sub 2}O-(25-x)K{sub 2}O-70(0.4ZnO+0.6P{sub 2}O{sub 5})+5MnO{sub 2} (x = 4,8,12,16 and 20 mol %) have been prepared by melt quenching technique. The thermal and mechanical properties of the glasses have been evaluated as a function of mixed alkali content. Glass transition temperature and Vickers's hardness of the glasses show a pronounced deviation from linearity at 12 mol%Li{sub 2}O. Theoretically estimated elastic moduli of the glasses show small positive deviations from linearity. MAE in these properties has been attributed to the localized changes in the glass network. The absorption spectra of Mn{sup 2+} ions in these glasses showed strong broad absorption band at 514 nm corresponding to the transition {sup 6}A{sub 1g}(S){yields}{sup 4}T{sub 1g}(G), characteristic of manganese ions in octahedral symmetry. The fundamental absorption edge in UV region is used to study the optical transitions and electronic band structure. From UV absorption edge, optical band gap energies have been evaluated. Band gap energies of the glasses have exhibited MAE and shows minimum value for 12 mol%Li{sub 2}O glass.

  3. Information Theoretic Causal Coordination

    DTIC Science & Technology

    2013-09-12

    his 1969 paper, Clive Granger , British economist and Nobel laureate, proposed a statistical def- inition of causality between stochastic processes. It...showed that the directed infor- mation, an information theoretic quantity, quantifies Granger causality . We also explored a more pessimistic setup...Final Technical Report Project Title: Information Theoretic Causal Coordination AFOSR Award Number: AF FA9550-10-1-0345 Reporting Period: July 15

  4. Theoretical and computational chemistry.

    PubMed

    Meuwly, Markus

    2010-01-01

    Computer-based and theoretical approaches to chemical problems can provide atomistic understanding of complex processes at the molecular level. Examples ranging from rates of ligand-binding reactions in proteins to structural and energetic investigations of diastereomers relevant to organo-catalysis are discussed in the following. They highlight the range of application of theoretical and computational methods to current questions in chemical research.

  5. Glass-An Environmental Protector

    SciTech Connect

    MARRA, JAMES

    2004-11-01

    From asbestos abatement to lead paint removal to nuclear waste stabilization and even to heavy metal removal using microorganisms, glass has great potential as a solution to many environmental problems. The ability to accommodate an array of chemical elements within the glass structure has facilitated the use of glass as a medium for the stabilization of numerous hazardous substances. The resulting glasses have proven to be durable enough for direct land disposal. In many cases, the stabilized forms have been deemed suitable for re-use in other applications. As recycling and hazardous material treatment become even more important in the global materials cycle, it is a certainty that glass will assume a prominent role.

  6. Relaxation in quantum glasses

    NASA Astrophysics Data System (ADS)

    Ancona Torres, Carlos E.

    The Ising model in transverse field provides the simplest description of a quantum glass. I study two systems that are realizations of the Ising model in transverse field, LiHoxY1-- xF4 and Rb1-- x(NH4)xH2PO 4. In the spin glass LiHoxY1-- xF4, applying a magnetic field Ht transverse to the Ising direction introduces tunneling between the bare Ising eigenstates. In addition, the coupling between the transverse dipolar interaction and the transverse field introduces entanglement or tunable random fields depending on the concentration. By comparing the classical and quantum transitions in LiHo0.198Y0.802F4 and LiHo 0.167Y0.833F4, I characterize the crossover from random field dominated behavior in the 19.8% sample to entanglement dominated behavior in the 16.7% sample. The quantum transition in the 19.8% sample is dominated by the limit on its correlation length caused by the random fields, while the dominant effect in the 16.7% sample is the enhanced tunneling rate introduced by entanglement. The proton glass Rb1--x(NH 4)xH2PO4 relaxes through tunneling of protons in the hydrogen bonds of the crystal, yielding an effective Ising model in transverse field. Since this field cannot be tuned directly, I combine bulk dielectric susceptibility measurements with neutron Compton scattering measurements of the local tunneling potential in two different concentrations, x = 35% and 72%. I find that tunneling drives the fastest relaxation processes at temperatures as high as 20 K and explicitly calculate the tunneling rate from the tunneling potential of the hydrogen bond. Moreover, the structural mechanism for the glassy relaxation allows a real-space picture of the relaxation dynamics to be correlated to the free energy description of aging. I find that the glassy relaxation is driven by the sequential diffusion of defects called Takagi configurations with a classical to quantum crossover in the relaxation at 3 K. I relate the relaxation rate to the quantum action of tunneling

  7. From Christmas Ornament to Glass Electrode

    NASA Astrophysics Data System (ADS)

    da Rocha, Rogério T.; Gutz, Ivano G. R.; Do Lago, Claudimir L.

    1995-12-01

    In potentiometric techniques, pH measurements require a costly and fragile accessory: the glass electrode. A glass electrode is difficult to make because the wall of the sensing glass bulb must be very thin, and glass of special composition is required. Although the glass bulb may be made by a skilled glazier, we choose a more impressive and simple way. The glass bulb can be made from a Christmas-tree ornamental ball.

  8. Third order nonlinear optical properties of bismuth zinc borate glasses

    SciTech Connect

    Shanmugavelu, B.; Ravi Kanth Kumar, V. V.; Kuladeep, R.; Narayana Rao, D.

    2013-12-28

    Third order nonlinear optical characterization of bismuth zinc borate glasses are reported here using different laser pulse durations. Bismuth zinc borate glasses with compositions xBi{sub 2}O{sub 3}-30ZnO-(70-x) B{sub 2}O{sub 3} (where x = 30, 35, 40, and 45 mol. %) have been prepared by melt quenching method. These glasses were characterized by Raman, UV-Vis absorption, and Z scan measurements. Raman and UV-Vis spectroscopic results indicate that non-bridging oxygens increase with increase of bismuth content in the glass. Nonlinear absorption and refraction behavior in the nanosecond (ns), picosecond (ps), and femtosecond (fs) time domains were studied in detail. Strong reverse saturable absorption due to dominant two-photon absorption (TPA) was observed with both ps and fs excitations. In the case of ns pulse excitations, TPA and free-carrier absorption processes contribute for the nonlinear absorption. Two-photon absorption coefficient (β) and the absorption cross section due to free carriers (σ{sub e}) are estimated by theoretical fit of the open aperture Z-scan measurements and found to be dependent on the amount of bismuth oxide in the glass composition. In both ns and fs regimes the sign and magnitude of the third order nonlinearity are evaluated, and the optical limiting characteristics are also reported.

  9. Direct laser writing of nonlinear properties in photosensitive glass

    NASA Astrophysics Data System (ADS)

    Papon, Gautier; Choi, Jiyeon; Bellec, Matthieu; Royon, Arnaud; Bourhis, Kevin; Canioni, Lionel; Cardinal, Thierry

    2011-03-01

    A 1030 nm pulsed femtosecond laser has been use to induce modifications in silver containing glass namely femto-photo luminescent glass (FPL) and Photo-thermo refractive glass (PTR). The 5W 10Mhz laser is focused at a depth of 200 μm in the glass using a 0,52 NA objective. The output polarization of the laser is TM. The tailoring of the number of pulses, pulse energy and repetition rate is achieve by acousto-optic filtering. The interaction resulted in the creation of stable pipe-shaped silver clusters forming bellow refraction-limit 3D structures. Those nano-structures exhibit non-linear properties such as SHG and THG as well as fluorescence. Due to multiphoton absorption, free electrons are created in the central part of the beam, enabling the reduction of Ag+ silver ions into Ag0 and subsequently AgmX+. The cumulated thermal effect of the pulses weakens the glass matrix allowing the diffusion of the AgmX+. The ion concentration gradient creates a buried electric field enabling non-linear properties. Influences of polarization, dose and fluence on the nonlinear properties are investigated. Our explanation of the causes of SHG and THG are validated by the accordance between the theory and the measurement. Comparisons between theoretic model and our results showing accordance in the limits of out 2D model are demonstrated using different incoming polarizations.

  10. Modelling the sulfate capacity of simulated radioactive waste borosilicate glasses

    SciTech Connect

    Bingham, Paul A.; Vaishnav, Shuchi; Forder, Sue D.; Scrimshire, Alex; Jaganathan, Balaasaran; Rohini, Jijy; Marra, James C.; Fox, Kevin M.; Pierce, Eric M.; Workman, Phyllis; Vienna, John D.

    2016-11-10

    In this paper, the capacity of simulated high-level radioactive waste borosilicate glasses to incorporate sulfate has been studied as a function of glass composition. Combined Raman, 57Fe Mössbauer and literature evidence supports the attribution of coordination numbers and oxidation states of constituent cations for the purposes of modelling, and results confirm the validity of correlating sulfate incorporation in multicomponent borosilicate radioactive waste glasses with different models. A strong compositional dependency is observed and this can be described by an inverse linear relationship between incorporated sulfate (mol% SO42-) and total cation field strength index of the glass, Σ(z/a2), with a high goodness-of-fit (R2 ≈ 0.950). Similar relationships are also obtained if theoretical optical basicity, Λth (R2 ≈ 0.930) or non-bridging oxygen per tetrahedron ratio, NBO/T (R2 ≈ 0.919), are used. Finally, results support the application of these models, and in particular Σ(z/a2), as predictive tools to aid the development of new glass compositions with enhanced sulfate capacities.

  11. Manganese modified structural and optical properties of bismuth silicate glasses

    NASA Astrophysics Data System (ADS)

    Dult, Meenakshi; Kundu, R. S.; Berwal, Neelam; Punia, R.; Kishore, N.

    2015-06-01

    Glass system with compositions xMnO2-(60-x) Bi2O3-40SiO2 have been synthesized by standard melt quench technique. X-ray diffraction patterns confirm the amorphous nature of as-prepared glass samples. The values of density have been measured and molar volume determined is found to decrease with increase in MnO2 content. Theoretical calculations of crystalline volume (Vc) have also been made. The glass transition temperature (Tg) determined using differential scanning calorimetry (DSC) is observed to increase with increase in MnO2 content. The structural analysis has been carried out using FTIR and Raman spectroscopy. In the present glass system, MnO2 acts as network modifier and exists in MnO6 structural units. Bismuth acts both as network former with BiO3 pyramidal units as well as network modifier with BiO6 octahedral units in the present glass system. SiO2 exists in form of SiO4 tetrahedral structural units with two non-bridging oxygens (NBO's). The optical band gap energy (Eg) has been estimated from Tauc's plot for direct transitions, it decreases with increase in manganese content.

  12. Modelling the sulfate capacity of simulated radioactive waste borosilicate glasses

    DOE PAGES

    Bingham, Paul A.; Vaishnav, Shuchi; Forder, Sue D.; ...

    2016-11-10

    In this paper, the capacity of simulated high-level radioactive waste borosilicate glasses to incorporate sulfate has been studied as a function of glass composition. Combined Raman, 57Fe Mössbauer and literature evidence supports the attribution of coordination numbers and oxidation states of constituent cations for the purposes of modelling, and results confirm the validity of correlating sulfate incorporation in multicomponent borosilicate radioactive waste glasses with different models. A strong compositional dependency is observed and this can be described by an inverse linear relationship between incorporated sulfate (mol% SO42-) and total cation field strength index of the glass, Σ(z/a2), with a highmore » goodness-of-fit (R2 ≈ 0.950). Similar relationships are also obtained if theoretical optical basicity, Λth (R2 ≈ 0.930) or non-bridging oxygen per tetrahedron ratio, NBO/T (R2 ≈ 0.919), are used. Finally, results support the application of these models, and in particular Σ(z/a2), as predictive tools to aid the development of new glass compositions with enhanced sulfate capacities.« less

  13. Replica symmetry breaking in cold atoms and spin glasses

    NASA Astrophysics Data System (ADS)

    Rotondo, P.; Tesio, E.; Caracciolo, S.

    2015-01-01

    We consider a system composed by N atoms trapped within a multimode cavity, whose theoretical description is captured by a disordered multimode Dicke model. We show that in the resonant, zero-field limit the system exactly realizes the Sherrington-Kirkpatrick model. Upon a redefinition of the temperature, the same dynamics is realized in the dispersive, strong-field limit. This regime also gives access to spin-glass observables which can be used to detect replica symmetry breaking.

  14. Glass Ceramic Formulation Data Package

    SciTech Connect

    Crum, Jarrod V.; Rodriguez, Carmen P.; McCloy, John S.; Vienna, John D.; Chung, Chul-Woo

    2012-06-17

    A glass ceramic waste form is being developed for treatment of secondary waste streams generated by aqueous reprocessing of commercial used nuclear fuel (Crum et al. 2012b). The waste stream contains a mixture of transition metals, alkali, alkaline earths, and lanthanides, several of which exceed the solubility limits of a single phase borosilicate glass (Crum et al. 2009; Caurant et al. 2007). A multi-phase glass ceramic waste form allows incorporation of insoluble components of the waste by designed crystallization into durable heat tolerant phases. The glass ceramic formulation and processing targets the formation of the following three stable crystalline phases: (1) powellite (XMoO4) where X can be (Ca, Sr, Ba, and/or Ln), (2) oxyapatite Yx,Z(10-x)Si6O26 where Y is alkaline earth, Z is Ln, and (3) lanthanide borosilicate (Ln5BSi2O13). These three phases incorporate the waste components that are above the solubility limit of a single-phase borosilicate glass. The glass ceramic is designed to be a single phase melt, just like a borosilicate glass, and then crystallize upon slow cooling to form the targeted phases. The slow cooling schedule is based on the centerline cooling profile of a 2 foot diameter canister such as the Hanford High-Level Waste canister. Up to this point, crucible testing has been used for glass ceramic development, with cold crucible induction melter (CCIM) targeted as the ultimate processing technology for the waste form. Idaho National Laboratory (INL) will conduct a scaled CCIM test in FY2012 with a glass ceramic to demonstrate the processing behavior. This Data Package documents the laboratory studies of the glass ceramic composition to support the CCIM test. Pacific Northwest National Laboratory (PNNL) measured melt viscosity, electrical conductivity, and crystallization behavior upon cooling to identify a processing window (temperature range) for melter operation and cooling profiles necessary to crystallize the targeted phases in the

  15. A visual analysis of gender bias in contemporary anatomy textbooks.

    PubMed

    Parker, Rhiannon; Larkin, Theresa; Cockburn, Jon

    2017-05-01

    Empirical research has linked gender bias in medical education with negative attitudes and behaviors in healthcare providers. Yet it has been more than 20 years since research has considered the degree to which women and men are equally represented in anatomy textbooks. Furthermore, previous research has not explored beyond quantity of representation to also examine visual gender stereotypes and, in light of theoretical advancements in the area of intersectional research, the relationship between representations of gender and representations of ethnicity, body type, health, and age. This study aimed to determine the existence and representation of gender bias in the major anatomy textbooks used at Australian Medical Schools. A systematic visual content analysis was conducted on 6044 images in which sex/gender could be identified, sourced from 17 major anatomy textbooks published from 2008 to 2013. Further content analysis was performed on the 521 narrative images, which represent an unfolding story, found within the same textbooks. Results indicate that the representation of gender in images from anatomy textbooks remain predominantly male except within sex-specific sections. Further, other forms of bias were found to exist in: the visualization of stereotypical gendered emotions, roles and settings; the lack of ethnic, age, and body type diversity; and in the almost complete adherence to a sex/gender binary. Despite increased attention to gender issues in medicine, the visual representation of gender in medical curricula continues to be biased. The biased construction of gender in anatomy textbooks designed for medical education provides future healthcare providers with inadequate and unrealistic information about patients.

  16. Race and Gender in Immigration: A Continuing Saga with Different Encryptions

    ERIC Educational Resources Information Center

    Joaquin, Edward; Johnson-Bailey, Juanita

    2015-01-01

    The authors examine the U.S. contemporary immigrant and transnational migration phenomena and the historical immigrant experience using a postcolonial theoretical framework. In this chapter, the issues of race and gender and current political positions are discussed.

  17. Race and Gender in Immigration: A Continuing Saga with Different Encryptions

    ERIC Educational Resources Information Center

    Joaquin, Edward; Johnson-Bailey, Juanita

    2015-01-01

    The authors examine the U.S. contemporary immigrant and transnational migration phenomena and the historical immigrant experience using a postcolonial theoretical framework. In this chapter, the issues of race and gender and current political positions are discussed.

  18. Energetics of glass fragmentation: Experiments on synthetic and natural glasses

    NASA Astrophysics Data System (ADS)

    Kolzenburg, S.; Russell, J. K.; Kennedy, L. A.

    2013-11-01

    Natural silicate glasses are an essential component of many volcanic rock types including coherent and pyroclastic rocks; they span a wide range of compositions, occur in diverse environments, and form under a variety of pressure-temperature conditions. In subsurface volcanic environments (e.g., conduits and feeders), melts intersect the thermodynamically defined glass transition temperature to form glasses at elevated confining pressures and under differential stresses. We present a series of room temperature experiments designed to explore the fundamental mechanical and fragmentation behavior of natural (obsidian) and synthetic glasses (Pyrex™) under confining pressures of 0.1-100 MPa. In each experiment, glass cores are driven to brittle failure under compressive triaxial stress. Analysis of the load-displacement response curves is used to quantify the storage of energy in samples prior to failure, the (brittle) release of elastic energy at failure, and the residual energy stored in the post-failure material. We then establish a relationship between the energy density within the sample at failure and the grain-size distributions (D-values) of the experimental products. The relationship between D-values and energy density for compressive fragmentation is significantly different from relationships established by previous workers for decompressive fragmentation. Compressive fragmentation is found to have lower fragmentation efficiency than fragmentation through decompression (i.e., a smaller change in D-value with increasing energy density). We further show that the stress storage capacity of natural glasses can be enhanced (approaching synthetic glasses) through heat treatment.

  19. Database and Interim Glass Property Models for Hanford HLW Glasses

    SciTech Connect

    Hrma, Pavel R.; Piepel, Gregory F.; Vienna, John D.; Cooley, Scott K.; Kim, Dong-Sang; Russell, Renee L.

    2001-07-24

    The purpose of this report is to provide a methodology for an increase in the efficiency and a decrease in the cost of vitrifying high-level waste (HLW) by optimizing HLW glass formulation. This methodology consists in collecting and generating a database of glass properties that determine HLW glass processability and acceptability and relating these properties to glass composition. The report explains how the property-composition models are developed, fitted to data, used for glass formulation optimization, and continuously updated in response to changes in HLW composition estimates and changes in glass processing technology. Further, the report reviews the glass property-composition literature data and presents their preliminary critical evaluation and screening. Finally the report provides interim property-composition models for melt viscosity, for liquidus temperature (with spinel and zircon primary crystalline phases), and for the product consistency test normalized releases of B, Na, and Li. Models were fitted to a subset of the screened database deemed most relevant for the current HLW composition region.

  20. LUBRICATING AND SIZING AGENT FOR GLASS FIBER,

    DTIC Science & Technology

    GLASS TEXTILES, SURFACE PROPERTIES), (*LUBRICANTS, GLASS TEXTILES), FIBERS , POLYVINYL ALCOHOL, STEARATES, CHROMIUM COMPOUNDS, ALUMINUM COMPOUNDS, MIXTURES, LACTATES, TITANIUM COMPOUNDS, MECHANICAL PROPERTIES, USSR