bluuebunny/crossref_metadata_2025 huggingface dataset:
Virtual Material Characterization of 3D Orthogonal Woven Composite Materials by Large-scale Computing
Authors: Lee Chang Sung , Chung Soon Wan , Shin Heon , Kim Seung Jo
Published: May 2005

In this paper, the virtual material characterization of three dimensional (3D) orthogonal woven composite materials is investigated by large-scale finite element analyses to predict the elastic properties. To numerically model the complex geometry of 3D orthogonal woven composites, a unit structure including the stuffer yarns, filler yarns, weaver yarns, and the resin region is generated based on direct numerical simulation (DNS) and the unit structures with the same pattern are assembled into an orthogonal woven composite structure composed of several millions of degrees of freedom. The influence of the geometrical irregularities, such as the inconsistent tow spacing and the waviness of the filler yarn, on the mechanical properties are also discussed by separately generating the yarns and the resin. From the numerical examples, it is shown that the pattern of tow distribution affects the shear modulus, and the direct modeling of the wavy yarns can produce more accurate stiffness knockdown. It is also emphasized that large-scale numerical analyses can be one of the methodologies sufficient for the material characterization of the orthogonal woven composites and can be more applicable in the realistic structure subject to complex loading compared to the unit cell approach.
Torsional Behavior of a Wood-based Composite Beam
Authors: Francescato P. , Pastor J. , Enab T.
Published: May 2005

Currently, wood has been undergoing a renewal process in the form of wood-based composite materials. Kerto® (FinnForest), one such wood-based composite material, is a laminated veneer lumber (LVL) obtained by unwinding spruce trees. To obtain the balanced moduli in torsion hGJi of such materials, two finite element method (FEM) Fortran approaches (in displacement and stress) have been proposed for these laminate composites, under the Saint Venant assumption. In addition to the hGJi, the torsion center position and highly precise solution fields in displacement and stress are obtained. Moreover, the performance of the proposed methods make it possible to take into account the effect of adhesive film. In order to validate both the approaches, we finally compare their results with the experimental values obtained from the torsion tests on specimens taken directly from the Kerto® panels, and with ANSYS modeling of the whole beam.
Utopia or Utopias in the Gaps: From the Political to the ‘Domestic’
Authors: Maffesoli Michel
Published: May 2005

We all face the requirement to put our knowledge in perspective. If there be an intellectual questioning it is because there is in fact already a questioning of societal values, a popular concern, a lived recognition of Paul Valéry's accurate but simple phrase: ‘We civilizations know that we are mortal.’ I think that questioning of the two great indicators of modern civilization in the tradition known as ‘Judeo-Christian’ - or, as I prefer, ‘semitico-western-modern’, to rightly include what was a cultural exception in the Semitic world - requires, over and above critical thought, radical thinking, thinking that goes to the roots.
For a Feeling Humanism: The Political Emergence of the Emotions
Authors: Sodré Muniz
Published: May 2005

Al mêsr is the name for Egypt in Arabic. This word, which also means ‘earth’, comes from the same root as the word al massêer meaning ‘destiny’. I think it is interesting to mention this play on words when approaching the possibilities for a new humanism, for we know that all discourse and perception spring from a nucleus of identity. Out of it and towards it speakers and listeners are positioned. Pascal described this nucleus as an ordre du cœur (order of the heart), quite possibly following Parmenides, whose ‘intrepid heart’, atremes etor, evoked a propensity to run the emotional risks presented by opposition, ambivalence and the unsayable in what is being spoken.
For an Enlargement of Human Rights
Authors: Yacoub Joseph
Published: May 2005

Given the excessive moralization of human rights and their universal ideologization, which has led to unfortunate consequences such as erasure of cultural differences and standardization, given the right, and even the duty, to intervene (the right of the strongest), and the craze for ‘democracy’ despite the will of peoples, the time has come to undertake an academic analysis of the founding texts in order to make them intelligible, in spite of the fact that human rights have become a bible. Even the revealed word of the Bible is scrutinized by exegetical analysis, historical criticism and hermeneutics, which have not stopped it surviving. It should be the same for human rights.
A Life Not Worth Living?
Authors: Paterson Craig
Published: May 2005

The work of Dan Brock and Helga Kuhse is typical of the current stream of thought rejecting the validity of sanctity of life appeals to instill objective inviolable worth in human life regardless of the quality of life of the patient. The context of a person’s life is supremely important. In their systems life can have high value, yet the value of life can be outweighed by the force of other disvalues. The notion of quality of life has increasingly come to signify the measurement of the worth of a person’s life itself. Having a life equals personal life. Any objectivity to life resides in ‘personal’, ‘biographical’, or ‘creative’ life, not mere biological life. Personal life represents the minimal threshold for any objective worth.

In responding to this challenge, John Finnis has argued extensively that life is an intrinsic good - a basic human good. Following from our grasp of human life as a basic incommensurable good, it cannot be practically reasonable both to affirm that (a) ‘human life is a basic human good’, and (b) that ‘human life qua human life can be intentionally acted against to its destruction’. Yet, if the good of human life can be considered self-evident, the self-evidence of the basic human good qua good does not mean that dialectical reasoning cannot be engaged in to indirectly support the practical reasonableness of respecting the good of human life in the deliberative choices that persons make concerning their actions. It is to the use of such dialectical reasoning, supportive of the status of human life as such a basic human good, that the article is primarily concerned to draw out and articulate.
Criminalizing War: Criminology as Ceasefire
Authors: Ruggiero Vincenzo
Published: May 2005

This article attempts to argue that the notion of ‘war as value’ has enjoyed unmerited longevity, and that a sociological-criminological analysis of war may today lead to its unconditional criminalization. Before presenting the criminalization argument, however, a brief analysis of how mainstream criminology has failed to address war and of the recent development of a new criminology of war is provided. Functionalism, labelling, conflict theory, abolitionism, ideas around corporate and state crime, as well as social disadvantage, in the form of international relative deprivation, are discussed with a view to determining whether within criminology itself pacifist resources can be found.
Matrix Crack Detection in Thin-walled Composite Beam using Genetic Fuzzy System
Authors: Pawar Prashant M. , Ganguli Ranjan
Published: May 2005

Since thin-walled composite structures are widely used in structural engineering, damage in such structures is an important issue of research. Matrix cracking is a principal cause of failure in composites. In the present study, a composite matrix cracking model is implemented in a thin-walled hollow circular cantilever beam using an effective stiffness approach. Such structures are used to model connecting shafts and helicopter tail boom, for example, because of their high stiffness-to-weight ratios and excellent crashworthiness characteristics. The effect of variation in crack density on the fundamental frequency, for various combinations of 1/2 m =90n s composite is studied. Using these change in frequencies due to matrix cracking, a genetic fuzzy system for crack density and crack location detection is generated. The genetic fuzzy system combines the uncertainty representation characteristics of fuzzy logic with the learning ability of genetic algorithm. It is observed that the success rate of the genetic fuzzy system in the presence of noise is dependent on crack density (level of damage), number of 90 plies, angle of constraining layer (), and noise level. It is found that the genetic fuzzy system shows excellent damage detection and isolation performance, and is robust to presence of noise in data.
Dynamic Characteristics of ER Fluid-filled Composite Plate using Multielectrode Configuration
Authors: Cho Ki-Dae , Lee In , Han Jae-Hung
Published: May 2005

In this research, a smart structure with multielectrode configuration has been proposed, which contains electrorheological (ER) fluid. Multielectrode configuration gives the structure a capability to change its modal characteristics effectively. The proposed configuration also provides the effective vibration control performance with reduced power consumption in the smart structures. A finite element model has been developed for the analysis of a smart composite plate under fully and partially applied electric fields. The numerical results of the composite plate with ER fluid have been compared with the experimental results. The performance and energy consumption of the control system have been experimentally investigated for various applied areas of electric field by applying a semi-active control law to the vibrating composite plate.
Dynamic Performance of a Disk-type Magnetorheological Fluid Damper under AC Excitation
Authors: Zhu Changsheng
Published: May 2005

It is shown that the dynamic behavior of a disk-type magnetorheological (MR) fluid damper based on shear mode operation for rotational machinery can be controlled by the application of an external DC magnetic field produced by a low-voltage electromagnetic coil and that the disk-type MR fluid damper can effectively attenuate the rotor vibration. In this article, the dynamic behavior of the disk-type MR fluid damper for attenuating rotor vibration under AC sinusoidal magnetic fields is experimentally studied on a flexible rotor. It is shown that as the frequency of AC sinusoidal magnetic field increases, the capability of the disk-type MR fluid damper to attenuate rotor vibration significantly reduces. There is a maximum frequency of AC sinusoidal magnetic field for a given magnetic field strength, and a minimum strength of AC sinusoidal magnetic field for a given frequency of AC sinusoidal magnetic field to realize the MR effect. When the frequency of AC sinusoidal magnetic field is over the maximum frequency or the applied strength of AC sinusoidal magnetic field is less than the minimum strength of AC sinusoidal magnetic field, the MR activity almost completely disappears and the dynamic behavior of the disk-type MR fluid dampers under AC magnetic field is the same as that without magnetic field. Since the AC sinusoidal magnetic field applied in the disk-type MR fluid damper results in the amplitude-modulated phenomenon in the rotor motion, it is better to use the DC magnetic field than to use the AC sinusoidal magnetic field to control the dynamic behavior of the disk-type MR fluid dampers in the rotor vibration control of view.
Character, virtue and physical education
Authors: Jones Carwyn
Published: May 2005

In this article I argue that until the full complexity of the psychology of moral personality, moral action, and moral learning is recognized, the prospect of physical education, and team sports in particular, being utilized for moral and social development is slim. Similarly a recognition of the multifarious, heterogeneous and context specific account of moral goodness must also be embraced. Once we move away from the dominant reductive account of moral action and moral goodness, a more realistic and appropriate account of moral pedagogy and the moral educator can emerge. The potential of physical education lessons, and the physical education teacher to contribute to the cultivation of moral characters, good habits and decent players, can then be evaluated more carefully.
The peasant and his body
Authors: Bourdieu Pierre
Published: May 2005

Based on a study of his childhood village of Béarn in southwestern France in the 1960s combining social history, statistics, and ethnography, the author shows how economic and social standing influence the rising rates of bachelorhood in a peasant society based on primogeniture through the mediation of the embodied consciousness that men acquire of this standing. The scene of a local ball on the margins of which bachelors gather serves to highlight and dissect the cultural clash between country and city and the resulting devaluation of the young men from the hamlet as urban categories of judgment penetrate the rural world. Because their upbringing and social position lead them to be sensitive to ‘ tenue’ (appearance, clothing, bearing, conduct) as well as open to the ideals of the town, young women assimilate the cultural patterns issued from the city more quickly than the men, which condemns the latter to be gauged against yardsticks that make them worthless in the eyes of potential marriage partners. As the peasant internalizes in turn the devalued image that others form of him through the prism of urban categories, he comes to perceive his own body as an ‘em-peasanted’ body, burdened with the traces of the activities and attitudes associated with agricultural life. The wretched consciousness that he gains of his body leads him to break solidarity with it and to adopt an introverted attitude that amplifies the shyness and gaucheness produced by social relations marked by the extreme segregation of the sexes and the repression of the sharing of emotions.
The limitations of whiteness and the boundaries of Englishness
Authors: Hickman Mary J. , Morgan Sarah , Walter Bronwen , Bradley Joseph
Published: May 2005

The focus of this article is the second-generation Irish in England. It is based on data collected as part of the Irish 2 project, which examined processes of identity formation amongst the second-generation Irish population in England and Scotland. The article examines and maps identifications and positionings of second-generation Irish people and discusses how two hegemonic domains - Ireland and England - intersect in the lives of the children of Irish-born parents, with material and psychological consequences. Their positionings in multiethnic Britain are compared with those of ‘visible’ minority ethnic groups, and their narratives of belonging and non-belonging are analysed in terms of the limitations of whiteness and the boundaries of Englishness.
Rawls’s political ontology
Authors: Pettit Philip
Published: May 2005

The background thesis is that an implicit ontology of the people and the relation between the people and the state often shapes how we think in normative terms about politics. This article attempts to defend that thesis in relation to Rawls. The argument is that the rejection of an image of the people as a group agent connects with his objection to utilitarianism and the rejection of an image of the people as a mere aggregate connects with his objection to libertarianism. Rawls, it is argued, holds by an in-between picture and it is this that explains many of his most distinctive commitments.
The limits of John Rawls’s pluralism
Authors: Mouffe Chantal
Published: May 2005

This article brings to the fore the shortcomings of the type of pluralism advocated by John Rawls both in Political Liberalism and in The Law of Peoples. It is argued that by postulating that the discrimination between what is and what is not legitimate is dictated by rationality and morality, Rawls’s approach forecloses recognition of the properly political moment. Exclusions are presented as being justified by reason and the antagonistic dimension of politics is not acknowledged. This article also takes issue with Rawls’s ‘realistic utopia’, asserting that despite the reference to ‘decent’ hierarchical societies, it amounts to a universalization of the western liberal model.
‘Forty acres and a mule’ for women: Rawls and feminism
Authors: Okin Susan Moller
Published: May 2005

This article assesses the development of Rawls’s thinking in response to a generation of feminist critique. Two principle criticisms are sustainable throughout his work: first, that the family, as a basic institution of society, must be subject to the principles of justice if its members are to be free and equal members of society; and, second, that without such social and political equality, justice as fairness is as meaningful to women as the unrealized promise of ‘Forty acres and a mule’ was to the newly freed slaves.
Young Service Users as Co-researchers
Authors: McLaughlin Hugh
Published: May 2005

This article explores some of the methodological challenges in working with young service users as co-researchers. The issues and concerns are highlighted using the national evaluation of the NSPCC’s Young People’s Centres as the vehicle for the discussion. In particular the article highlights the ethical issues and practical difficulties of this approach, demonstrating how these might be addressed. This article is offered as a contribution to the debate as to how best to involve young service users in research.
What’s the Point of It All?
Authors: Cupitt Don
Published: May 2005

In the modern period the decline of traditional dogmatic religious belief has led to a remarkable return of the great questions of life that so worried the first speculative thinkers 2500 years ago. As a result, the first priority for modern religious enquirers is not ‘what must I do to be saved?’, but ‘what’s the point of it all?’ Why does anything at all exist?
Does Monarchy Matter?
Authors: Starkey David
Published: May 2005

The constitutional history of America, France and Britain, as well as monolithic organizations past and present, shows that human beings cleave to single rule - that we tend to develop quasi-royal dynasties, from Livia and Augustus to Bill and Hilary Clinton. Monarchy is not quaint; it is universal. Nevertheless, it is most surprising that there is still a monarchy in Britain. This essay asks, ‘Does the monarchy matter... to the British?’ and answers ‘Yes: it did by its presence and does still by its absence’. Its abolition would involve reconstructing both the Constitution and a British sense of identity.
Rational polynomial representation of ribonucleotide reductase activity
Authors: Radivoyevitch Tomas , Kashlan Ossama B , Cooperman Barry S
Published: May 2005

Background

Recent data suggest that ribonucleotide reductase (RNR) exists not only as a heterodimer R12R22 of R12 and R22 homodimers, but also as tetramers R14R24 and hexamers R16R26. Recent data also suggest that ATP binds the R1 subunit at a previously undescribed hexamerization site, in addition to its binding to previously described dimerization and tetramerization sites. Thus, the current view is that R1 has four NDP substrate binding possibilities, four dimerization site binding possibilities (dATP, ATP, dGTP, or dTTP), two tetramerization site binding possibilities (dATP or ATP), and one hexamerization site binding possibility (ATP), in addition to possibilities of unbound site states. This large number of internal R1 states implies an even larger number of quaternary states. A mathematical model of RNR activity which explicitly represents the states of R1 currently exists, but it is complicated in several ways: (1) it includes up to six-fold nested sums; (2) it uses different mathematical structures under different substrate-modulator conditions; and (3) it requires root solutions of high order polynomials to determine R1 proportions in mono-, di-, tetra- and hexamer states and thus RNR activity as a function of modulator and total R1 concentrations.

Results

We present four (one for each NDP) rational polynomial models of RNR activity as a function of substrate and reaction rate modifier concentrations. The new models avoid the complications of the earlier model without compromising curve fits to recent data.

Conclusion

Compared to the earlier model of recent data, the new rational polynomial models are simpler, adequately fitting, and likely better suited for biochemical network simulations.
PKC translocation and ERK1/2 activation in compensated right ventricular hypertrophy secondary to chronic emphysema.
Authors: Avelar Erick , Jalili Thunder , Dong Li , Arvizo Joel , Hu Ping , Litwin Sheldon E , Mattson John P
Published: May 2005

Background

Right ventricular hypertrophy (RVH) is an important complication of chronic lung disease. However, the signal transduction pathways involved as well as the physiological changes to the right ventricle have not been investigated. Emphysema was produced in male, Syrian Golden hamsters by intra-tracheal instillation of 250 IU/kg elastase (Emp, n = 17). Saline treated animals served as controls (Con, n = 15).

Results

Nine months later, Emp hamsters had 75% greater lung volume, and evidence of RVH at the gross and myocyte level (RV:tibia length Emp 6.84 ± 1.18 vs. Con 5.14 ± 1.11 mg/mm; myocyte cross sectional area Emp 3737 vs. Con 2695 μm2), but not left ventricular hypertrophy. Serial echocardiographic analysis from baseline to nine months after induction of emphysema revealed increasing right ventricular internal dimension and decreased pulmonary artery acceleration time only in Emp hamsters. There was an increase in translocation of PKC βI and PKC ε from cytosolic to membranous cell fractions in RV of Emp hamsters. Phosphorylation of PKC ε was unchanged. Translocation of PKC α and βII were unchanged. Emp animals had a 22% increase in phospho-ERK 1/2, but no change in levels of total ERK 1/2 compared to Con.

Conclusion

These data suggest that PKC βI, ε and ERK 1/2 may play a role in mediating compensated RVH secondary to emphysema and may have clinical relevance in the pathogenesis of RVH.
Retraction Note: Inactivation of MAP kinase signalling in Myc Transformed Cells and Rescue by LiCl inhibition of GSK3
Authors: Al-Assar Osama , Crouch Dorothy H
Published: May 2005

The corresponding author submitted this article [1] to Molecular Cancer on the assumption that the co-author had agreed to the submission. Since this is not the case, the authors are retracting the article. The corresponding author is deeply sorry for any inconvenience this may have caused to the editorial and publishing staff. An apology is also extended to the readers.
Development of Innovative Three-Way Catalysts Containing Ceria–Zirconia Solid Solutions with High Oxygen Storage/Release Capacity
Authors: Sugiura Masahiro , Ozawa Masakuni , Suda Akihiko , Suzuki Tadashi , Kanazawa Takaaki
Published: May 2005

Innovative three-way catalysts containing ceria–zirconia solid solutions (CZ) with a ZrO2 content ranging from 5 to 75 mol% were developed. Such catalysts have very high oxygen storage/release capacity (OSC). The OSC of catalysts containing first-generation CZ was found to increase linearly with the amount of zirconia dissolved in the solid solution in the 0–20 mol% ZrO2 range. The thermal stability of the catalyst containing first-generation CZ was higher than that containing ceria. Second-generation CZ with greater OSC than first-generation CZ was developed by a homogeneous coprecipitation process, followed by heat-treatment below 1000 °C, enabling dissolution of zirconia into ceria up to 75 mol% zirconia as estimated by XRD. Third-generation CZ, CZ-doped alumina (ACZ), was developed by homogeneous coprecipitation based on the “diffusion barrier concept”. The OSC of ACZ was 23 times larger than that of pure ceria. The NOx emission over the catalyst containing ACZ was reduced by about a factor of five compared with that containing pure ceria. Toyota Motor Corp. has put three-way catalysts containing first-, second-, and third-generation CZ into practical use globally.
Theoretical Study of the Formation of a Benzene Cobalt Complex from Cobaltacyclopentadiene and Acetylene
Authors: Dahy AbdelRahman A , Suresh Cherumuttathu H , Koga Nobuaki
Published: May 2005

With the B3LYP theoretical method, the reaction of cobaltacyclopentadiene complex with acetylene in singlet and triplet states leading to benzene cobalt complex was studied in detail. In the most favorable path in the singlet state, an acetylene molecule attacks cobaltacyclopentadiene from the side, where the vacant d orbital extends over, so that [4 + 2] cycloaddition gives a η4-benzene complex without any activation energy, called the collapse mechanism. The reaction in the triplet state passes through a single transition state with an activation barrier of 14.1 kcal/mol, leading to the η6-benzene complex. The reactant of cobaltacyclopentadiene and the product of the benzene complex in the triplet state are more stable than those in the singlet state, whereas a substantial activation energy is required in the triplet state, suggesting that the spin may change during the reaction. Calculations of the crossing points between the singlet and triplet states showed that in the most favorable reaction path, the spin changes to the singlet state before passing through the triplet transition state, and that the collapse mechanism in the singlet state is followed. The energy required to lead to the crossing point for this spin change was calculated to be 7.0 kcal/mol, which is lower than the activation barrier.
One-Dimensional Coordination Polymers from the Self-Assembly of Copper(II) Carboxylates and 4,4′-Dithiobis(pyridine)
Authors: Horikoshi Ryo , Mikuriya Masahiro
Published: May 2005

A twisted ligand, 4,4′-dithiobis(pyridine), 4pds, was reacted with copper(II) carboxylates to synthesize one-dimensional coordination polymers: [Cu4(CH3COO)6(μ3-OH)2(4pds)2]n (1), [Cu(CH3COO)2(4pds)·6H2O]n (2), [{Cu2(C6H5COO)4}2(4pds)2]n (3), and [{Cu2[CH3(CH2)4COO]4}2(4pds)2]n (4). The crystal structure of 1 reveals a repeated rhomboid structure in which the Cu4(CH3COO)6(OH)2 core is linked by two 4pds ligands. The 4 : 2 (Cu : 4pds) stoichiometry of 1 transforms into the 1 : 1 (Cu : 4pds) one of 2 in aqueous solution. Compound 2 has a porous honeycomb-like structure, which is occupied by carboxylate ions and water molecules. Compounds 3 and 4 are zigzag chains consisting of alternate linking of the Cu2(RCOO)4 unit and 4pds ligand. The variable-temperature magnetic susceptibility data of 1 and 3 are consistent with the net antiferromagnetic interaction within the tetranuclear or dinuclear core.
Synthesis, Structure, and DNA Binding Studies of Copper(II) Complexes of Terpyridine Derivatives
Authors: Uma V , Vaidyanathan V G , Nair Balachandran Unni
Published: May 2005

Two copper(II) complexes, Cu(ttpy)22+1 and Cu(Brphtpy)22+2, were synthesized and characterized for their DNA binding and cleaving ability. The crystal structure of complex 1 reveals an axially compressed six-coordinate geometry around Cu(II). In spite of having an axially compressed geometry, the polycrystalline EPR spectrum of complex 1 at 298 K shows g|| > g⊥, indicating a dx2−y2 ground state for the Cu(II) complex. Both complexes 1 and 2 bind to CT DNA intercalatively with moderate binding strength (Kb = (8.4 ± 0.2) × 103 and (10.9 ± 0.2) × 104 M−1 (1 M = mol dm−3) respectively). Both of these complexes cleave plasmid DNA efficiently in the presence of peroxide.
Vigulariol, a New Metabolite from the Sea Pen Vigularia juncea
Authors: Su Jui-Hsin , Huang Ho-Cheng , Chao Chih-Hua , Yan Liang-Yu , Wu Yang-Chang , Wu Chin-Chung , Sheu Jyh-Horng
Published: May 2005

A new eunicellin-type diterpenoid, vigulariol (1), has been isolated from the sea pen Vigularia juncea. Metabolite 1 has been obtained previously as a side product from a chemical reaction; however, it was isolated for the first time from natural resources. Also, this study established the full structure of 1 and afforded the detailed assignments of 1H and 13C NMR spectral data.
Phase Separation of Gold Microcrystals in Glass with an Electric Field
Authors: Wang Guoliang , Liang Kaiming , Liu Wei , Zhou Feng , Shao Hua , Hu Anmin
Published: May 2005

Based on static electromagnetics theory and thermodynamics theory, a new model is proposed to describe the phase separation from the glass doped with metal particles in a static electric field. This model is proved by a heat-treatment experiment of boracic silicate glass doped with gold. The results indicate that the externally applied electric field promotes the phase separation of the glass and leads to a different size of the droplet phase just as this new model has predicted.
In Situ Study of Deformation Mechanisms in Sputtered Free-Standing Nanocrystalline Nickel Films
Authors: Mitra R. , Chiou A. , Weertman J.R.
Published: May 2005

Nickel films of 1.5–10-μm thickness, produced by dc magnetron sputtering and with disperse grain size distributions peaking in the 30–60-nm range, were subject to in situ tensile straining in a transmission electron microscope. The deformation was stopped frequently, while keeping the load applied, for transmission electron microscopy observation of the internal structure. Contrast changes occurred in many of the grains between strain increments. Ample evidence was seen of dislocation activity, which appears to be the major mechanism for deformation of the samples. Dislocations were seen in grains as small as 20 nm. Parallel arrays of roughly equally spaced dislocations were observed, spaced about 5–10-nm apart. Intergranular nanovoids were found to form and grow with accompanying strain relief in neighboring grains. The results of the current study are generally consistent with previous in situ investigations and contribute to the understanding of deformation mechanisms in free-standing thin films, which may differ somewhat from those in bulk nanocrystalline materials or in films attached to a substrate.
Friction and Scratch Resistance of Polymer Liquid Crystals: Effects of Magnetic Field Orientation
Authors: Brostow Witold , Jaklewicz Magdalena
Published: May 2005

We have studied PET/0.6 PHB, an alternating copolymer in which PET is poly(ethylene terephthalate) and PHB is p-hydroxybenzoic acid with the mole fraction of 0.6 PHB. It is a longitudinal polymer liquid crystal (PLC) with the LC sequences in the main chain and oriented along the chain backbone. Material not subjected to the magnetic field, specimens oriented along and perpendicularly to the flux of the magnetic field, were investigated. Static friction, dynamic friction, scratch penetration depth, and healing of the material were determined. Static and dynamic friction parameters for oriented samples have significant higher values for oriented samples. The best scratch resistance is found for the sample aligned along the magnetic field. The results are explained in terms of morphology revealed by scanning electron microscopy and phase structures.
Enhanced Polarization Switching Characteristics of Pb(Zr0.5Ti0.5)O3–Pt Nanocomposite Thin Films
Authors: Cheng Cheng-Wei , Tseng Yuan-Chieh , Wu Tai-Bor , Chou Li-Jen
Published: May 2005

The effect of nanoscale Pt particles embedded in ferroelectric matrix on the polarization switching characteristics of Pb(Zr0.5Ti0.5)O3(PZT) thin films of low thickness was investigated. Two different nanocomposite structures of PZT-Pt thin films were fabricated for the study. The first one incorporated a single layer of Pt nano-particles embedded in the PZT film, which was formed by annealing an ultrathin Pt layer that had been inserted into the middle of the deposited PZT. The other one had Pt nano-particles embedded uniformly and coherently in the lattice of the PZT matrix, which was generated by annealing the cosputtered films of PZT and Pt. The electric field applied on the films can be locally intensified near the embedded Pt particles, which markedly enhances the polarization switching characteristic of the above PZT-Pt nanocomposite films. Accordingly, a satisfactorily higher remanent polarization was obtained than exhibited by normal PZT films, but the coercive field was only slightly higher. However, adding an excess of Pt made the nanocomposite films too leaky to exhibit the enhancement. Moreover, the nanocomposite PZT-Pt films in the capacitor configuration of Pt/LaNiO3/PZT-Pt/LaNiO3/Pt also exhibited highly reliable polarization retention and fatigue resistance.
Influence of Tricalcium Aluminate Phase on In Vitro Biocompatibility and Bioactivity of Calcium Aluminate Bone Cement
Authors: Oh S.H. , Finones R. , Jin S. , Choi S.Y. , Kim K.N.
Published: May 2005

The influence of tricalcium aluminate (3CaO·Al2O3) phase doping on in vitro biocompatibility and bioactivity of calcium aluminate (CaO·Al2O3) based bone cement has been investigated. It is demonstrated that the presence of approximately 25% tricalcium aluminate in the bone cement remarkably improves the bioactivity, yet still retains desirable mechanical strength and biocompatibility. An intermediary compound layer such as Ca3Al2(OH)12 was formed on the surface of the doped sample onto which hydroxyapatite (HAp) began to form soon, after only 2 days of immersion in a simulated body fluid solution. This is about seven-fold acceleration in the HAp formation over undoped calcium aluminate cement on which it took approximately15 days to nucleate the HAp phase. The depth of the HAp-containing layer after60 days of soaking was as much as 85 μm, about an order of magnitude more than the undoped calcium aluminate cement. The dramatically accelerated nucleation and growth of hydroxyapatite caused by the presence of tricalcium aluminate is attributed to the occurrence of intermediate layer materials such as Ca3Al2(OH)12, which most likely acts as the nuclei for HAp formation. This doped bone cement can be useful for injectable orthopedic applications, as the setting time for hardening has also been significantly reduced (by a factor of at least 4) to a practical regime of tens of minutes.
Characterization of CeO2 Fine Particles Prepared by the Homogeneous Precipitation Method with a Mixed Solutionof Ethylene Glycol and Polyethylene Glycol
Authors: Uekawa Naofumi , Ueta Masayuki , Wu Yong Jun , Kakegawa Kazuyuki
Published: May 2005

Cerium oxide (CeO2) nanoparticles were obtained by heating a polyethylene glycol (PEG) solution of cerium nitrate hydrate [Ce(NO3)3 6H2O] at 383 K for 3 h. When the PEG, whose molecular weight was 20,000, was used for the preparation, the monodispersed CeO2, whose particle size was about 102 nm, was obtained. When the mixture of PEG20,000 and ethylene glycol (EG) was used to prepare the PEG solution of cerium nitrate hydrate, the average particle size increased from 102 nm to 660 nm with an increase in the EG content of the solution. The pore structure in the obtained CeO2 particles also depended on the weight ratio between EG and PEG20,000.
Morphology and Electrical Properties of Pure and Ti-Doped Gas-Sensitive Ga2O3 Film Prepared by Rheotaxial Growth and Thermal Oxidation
Authors: Chen Chin-Cheng , Chen Chiu-Chen
Published: May 2005

An n-type Ga2O3 semiconductor thin film was prepared by rheotaxial growth and thermal oxidation (RGTO) method on SiO2 and Al2O3 substrates. Multilayer growth technique was used to control grain size. The morphology and the electrical properties of the Ga and Ga2O3 films were measured as functions of thickness, temperature, and Ti dopant concentration. Measurements of the sensitivity, the response time, and the recovery time of the Ga2O3 films in response to ethanol and CO were carried out.The results showed that the grain size of Ga film increased with thickness, and a balls-on-ball type morphology was produced as the film exceeded 3000 Å. Ga2O3 nanowires were created when Ga films were oxidized under impure O2 atmosphere. Ga2O3 films had an optimum sensing temperature increasing from 625 °C for a5012 Å film to 675 °C for a 5.6-μm film. The films prepared by multilayer growth technique had smaller grain size, but the sensitivity remained unchanged. The films deposited on SiO2 substrate had a sensitivity higher by 28% than that on Al2O3. Doping of 0.28 at.% Ti enhanced nanowires growth, raised sensitivity by 6%, shortened response time from 40 to 30 s, but prolonged recovery time from 92 to130 s. Formation of nanowires resulted in an increase of sensitivity up to 50%.Doping of 2.18 at.% Ti led to the formation of nanoribbons with a sensitivity lowerby 8% and a recovery time shortened from 130 to 72 s. The RGTO method was shown to produce Ga2O3 gas-sensitive thin film with good reproducibility.
Deposition and Characterization of Diamond-Like Carbon Thin Films by Electro-Deposition Technique Using Organic Liquid
Authors: Ray S.C. , Bose B. , Chiou J.W. , Tsai H.M. , Jan J.C. , Kumar Krishna , Pong W.F. , DasGupta D. , Fanchini G. , Tagliaferro A.
Published: May 2005

Diamond-like carbon films were synthesized by electro-deposition technique from an organic liquid (a solution of alpha- and beta-pinenes in n-hexane) on silicon substrate at room temperature and at room pressure. The x-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectra, Raman spectra, photoluminescence (PL), and x-ray absorption near edge structure (XANES) spectra analysis were used to study the properties of the diamond-like carbon (as-deposited and annealed) films. The XRD measurement indicated that the film contains some diamond-crystalline phases whereas Raman spectra did not show any prominent diamond-like peak. PL intensity as higher for the as-deposited film and decreased with high-temperature vacuum annealing. FTIR spectra showed the presence of sp3 hybridization C–H bonds and their intensity decreases at higher annealing temperature. C and O K-edge XANES spectra showed that π* (sp2) intensity significantly decreases when the annealing temperature is 600 °C.
Mullite Precursor Synthesis in Aqueous Conditions: Dependence of Mullite Crystallization and Grain Size and Morphology on Solution pH and Precursor Salt
Authors: Lee Jae-Ean , Kim Jae-Won , Lee Je-Hyun , Jung Yeon-Gil , Paik Ungyu
Published: May 2005

The synthesis behavior of mullite in an aqueous system was investigated. Two kinds of aluminosilicate precursor sols were prepared by the dissolution of two kinds of salt (aluminum chloride hexahydrate, AlCl3·6H2O, and aluminum sulfate with 14–18 molecules of water, Al2[SO4]3·14–18H2O) into the mixture of colloidal silica sol. The effects of the solution pH, which was controlled by addition of ammonium hydroxide (NH4OH), and the type of aluminum salt on the mullite crystallization and the grain size and morphology in the sintered materials are discussed in this paper. It has been discovered that in an aqueous system, the mullitization temperature strongly depends on the solubility and decomposition temperature of the aluminum salt used and that the pH of the initial sol impacts the grain size and morphology of mullite, in addition to the homogeneity of mixture. Mullite is synthesized at 850 °C without resorting to the addition of an organic additive or nonaqueous solvent.
Characteristics of Alumina Diffusion Barrier Films on Hastelloy
Authors: Usov I. , Arendt P. , Stan L. , R. DePaula , Wang H. , Foltyn S. , Dowden P.
Published: May 2005

The diffusion behavior of elements constituting Hastelloy C-276 (C, Si, Mn, Co, W, Fe, Cr, Mo, and Ni) in alumina films was investigated using secondary ion mass spectroscopy. The films were deposited by ion-beam-assisted deposition and annealed in vacuum over a temperature range of 500–1000 °C. Characterization of film microstructure was performed using transmission electron microscopy and selected area diffraction analyses. The films were predominantly amorphous with alumina nanocrystallites nonuniformly dispersed throughout the volume both before and after annealing. A relatively wide interface region between the Hastelloy substrate and alumina film was formed in the as-deposited sample due to ion beam mixing. No diffusion of any of the substrate elements was observed after annealing, except for Mn, Cr, and Ni. The impurity depth distributions consisted of two components, which differed by several orders of magnitude with respect to diffusion coefficient and solubility. Activation energies and temperature dependencies of the diffusion coefficients were determined, and a diffusion mechanism was discussed.
Synthesis and Characterization of Synthetic F-Mica Containing Glass-Ceramics in the System SiO2·Al2O3·B2O3·CaO·MgO·Li2O·(K,Na)2O·F
Authors: Tulyaganov D.U. , Agathopoulos S. , Fernandes H.R. , Ferreira J.M.F.
Published: May 2005

Ions of Li, Na, K, and B were incorporated in Ca-mica, CaMg3Al2Si2O10F2. The crystallization process and the properties of the resulting glass-ceramics were experimentally determined, and the role of the anions and cations is discussed. According to the results, Li, K, and Na ions strongly affected the formation of the crystalline phases. Until 900 °C, pargasite and F-cannilloite amphiboles and KLi-mica were predominately crystallized. The two amphiboles are dissociated, yielding stable forsterite at 900 °C and Ca-mica and spinel at 950 °C. KLi-mica showed remarkable stability and growth within the investigated temperature range, until 1000 °C. The optimum crystallization temperature for the investigated glass-ceramics is between800 °C and 900 °C. The produced glass-ceramics exhibited capability for easy bulk crystallization, high whiteness, translucency, and mechanical and chemical properties suitable for several applications.
Effects of Conversion Parameters on the Transport Properties of YBCO Films in the BaF2 Ex Situ Process
Authors: Yoo J. , Leonard K.J. , Lee D.F. , Hsu H.S. , Heatherly L. , List F.A. , Rutter N.A. , Goyal A. , Paranthaman M. , Kroeger D.M.
Published: May 2005

The effects of conversion parameters on transport properties of YBa2Cu3O7-δ (YBCO) films on rolling assisted biaxially textured substrates (RABiTS) in the BaF2 ex situ process were investigated for total pressures Ptotal between 0.1 and 1.3 atm, water vapor pressures PH2O between approximately 7 and 70 Torr and processing temperatures TS between 700 and 790 °C. For this study, a 0.3-μm-thick Y–BaF2–Cu–O precursor film was deposited on a 1-cm-wide Ni=3 at.% W RABiTS with a buffer layer architecture of CeO2/YSZ/Y2O3/Ni deposited in single passes in various reel-to-reel systems for each layer. Under the conditions of Ptotal = 0.1 atm, TS = 740 °C and PO2 approximately 150 mTorr, JC > 2 MA/cm2 was obtained at 77 K and self field for PH2O ≤ 20 Torr. At higher PH2O (=70 Torr), however, the maximum attainable JC decreased. In addition, the JC at these higher PH2O dropped rapidly with increased dwell time. The highest JC, 2.5 MA/cm2, was achieved at 730 °C with Ptotal = 0.1 atm and PH2O approximately 7 Torr. Finally, the variation of IC with wet conversion time was performed at each processing temperature.
Comments on “Synthesis and structural characterization of rutile SnO2 nanocrystals” by Z. Chen, J.K.L. Lai, C.H. Shek, and H. Chen [J. Mater. Res. 18, 1289 (2003)]
Authors: Dolbec R. , El Khakani M.A. , Serventi A.M. , Saint-Jacques R.G.
Published: May 2005

The nanostructure, stoichiometry and sensing performance of SnO2 films grown by pulsed laser deposition (PLD) have been shown to be highly sensitive to the deposition conditions. In particular, PLD deposition under vacuum is known to produce films that are composed of both a polycrystalline SnO2 phase and an amorphous SnO phase, for deposition temperatures in the 20–600 °C range. The presence of such an amorphous SnO phase in the films greatly limits their practical use as gas-sensing devices.
Kinetic nature of hard magnetic Nd50Al15Fe15Co20 bulk metallic glass with distinct glass transition
Authors: Xia L. , Tang M.B. , Xu H. , Pan M.X. , Zhao D.Q. , Wang W.H. , Dong Y.D.
Published: May 2005

A hard magnetic Nd50Al15Fe15Co20 bulk metallic glass (BMG) was prepared in the shape of a rod up to 3 mm in diameter by suction casting. The glass transition and crystallization behaviors as well as their kinetic nature have been studied. In contrast to the previously reported hard magnetic Nd–Al–Fe–Co BMGs, Nd50Al15Fe15Co20 as-cast rod exhibits a distinct glass transition and multistep crystallization behaviors in the differential scanning calorimetry traces and lower coercivity. The BMG provides an ideal model for the investigation of glass transition and crystallization of hard magnetic Nd–Al–Fe–Co glass-forming alloys.
A sample preparation method for four point bend adhesion studies
Authors: Cui Zhenjiang , Ngo Sure , Dixit Girish
Published: May 2005

A method to prepare samples for four point bend testing is reported in this paper. The traditional method of sample preparation involves time-consuming steps of sawing with a diamond saw followed by polishing with fine grit to remove the roughness of the sidewall. The new method uses cleaving along the 〈100〉 crystallographic direction, which renders smooth surfaces and eliminates the polishing steps. Load–displacement curves comparing polished versus cleaved samples show that the new technique provides improved results. Elimination of fracture-inducing defects is the primary benefit of this method, which also leads to data with tighter distributions.
Polyol-mediated preparation of disklike (ZnSe)2·EN precursor and its conversion to ZnSe crystals with quasi-network structure
Authors: Shen Guozhen , Chen Di , Tang Kaibin , Qian Yitai
Published: May 2005

In this paper, we reported the rapid synthesis of disklike (ZnSe)2·EN precursor via a simple and convenient polyol method. Annealing the precursor in argon stream at 500 °C resulted in the formation of ZnSe crystals with unique quasi-network structure. The obtained samples were characterized by powder x-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy, infrared absorbance spectra, and thermogravimetric analysis. The influence of PEG200 on the final products in the system was also discussed.
Microstructural evolution in lead-free solder alloys: Part I. Cast Sn–Ag–Cu eutectic
Authors: Allen Sarah L. , Notis Michael R. , Chromik Richard R. , Vinci Richard P.
Published: May 2005

Coarsening of the ternary eutectic in cast Sn–Ag–Cu lead-free solder alloys was investigated. The process was found to follow r3 ∝ t kinetics where r is the rod radius of the dispersed phase and t is time. The effective activation energy for the process is 69 ± 5 kJmol-1. The two types of intermetallic rods, Cu6Sn5 and Ag3Sn, in the eutectic structure coarsen at different rates, with each having a different rate-controlling mechanism. The overall coarsening kinetics for the Sn–Ag–Cu ternary eutectic is significantly slower than that found for the Pb-Sn eutectic, which has implications for long-term reliability of Sn–Ag–Cu solder joints.
Microstructural evolution in lead-free solder alloys: Part II. Directionally solidified Sn-Ag-Cu, Sn-Cu and Sn-Ag
Authors: Allen Sarah L. , Notis Michael R. , Chromik Richard R. , Vinci Richard P. , Lewis Daniel J. , Schaefer Robert
Published: May 2005

The tin–silver–copper eutectic is a three-phase eutectic consisting of Ag3Sn plates and Cu6Sn5rods in a (Sn) matrix. It was thought that the two phases would coarsen independently. Directionally solidified ternary eutectic and binary eutectic samples were isothermally annealed. Coarsening of the Cu6Sn5rods in the binary and ternary eutectics had activation energies of 73 ± 3 and 82 ± 4 kJmol-1, respectively. This indicates volume copper diffusion is the rate controlling mechanism in both. The Ag3Sn plates break down and then coarsen. The activation energies for the plate breakdown process were 35 ± 3 and 38 ± 3 kJmol-1for the binary and ternary samples respectively. This indicates that tin diffusion along the Ag3Sn/(Sn) interfaces is the most likely the rate-controlling mechanism. The rate-controlling mechanisms for Cu6Sn5coarsening and Ag3Sn plate breakdown are the same in the ternary and binary systems, indicating that the phases evolve microstructurally independently of one another in the ternary eutectic.