bluuebunny/crossref_metadata_2025_split huggingface dataset:
The efficiency of electrokinetic pumping at a condition of maximum work
Authors: Griffiths Stewart K. , Nilson Robert H. 
Published: January 2005

AbstractNumerical methods are employed to examine the work, electric power input, and efficiency of electrokinetic pumps at a condition corresponding to maximum pump work. These analyses employ the full Poisson‐Boltzmann equations and account for both convective and conductive electric currents, including surface conductance. We find that efficiencies at this condition of maximum work depend on three dimensionless parameters, the normalized zeta potential, normalized Debye layer thickness, and a fluid property termed the Levine number indicating the nominal ratio of convective to conductive electric currents. Efficiencies at maximum work exhibit a maximum for an optimum Debye layer thickness when the zeta potential and Levine number are fixed. This maximum efficiency increases with the square of the zeta potential when the zeta potential is small, but reaches a plateau as the zeta potential becomes large. The maximum efficiency in this latter regime is thus independent of the zeta potential and depends only on the Levine number. Simple analytical expressions describing this maximum efficiency in terms of the Levine number are provided. Geometries of a circular tube and planar channel are examined.
A triple‐injection method for microchip electrophoresis
Authors: Tabuchi Mari , Baba Yoshinobu 
Published: January 2005

AbstractWe report here a novel triple injection method for microchip electrophoresis (µ‐CE) that results in a higher intensity of DNA peaks. This new method includes a triple‐repeated process of a combination of a sample loading voltage and a separation voltage in each interval, namely (loading time) + (separation time) + (loading time) + (separation time) + (loading time), prior to electrophoretic separation. All these injections were electrokinetically controlled by a software. Although the usual sample injection, which included the process of one 60 s electrokinetically application, was limited by the amount of sample, peaks of 40% higher intensity were obtained using the new method within half of the conventional injection time compared to the conventional method. Maximum peak intensity was successfully achieved with integration of the intensities of the triple‐repeated peaks by adjusting the application period of the separation voltage. Repetition of the sample loading voltage for an adjusted period with a further adjusted period of separation voltage in each interval may be an effective method for injection of samples that results in peaks with higher intensity.
System zones in capillary zone electrophoresis: Moving boundaries caused by freely migrating hydrogen ions
Authors: Beckers Jozef L. , Boček Petr 
Published: January 2005

AbstractWe demonstrate that system zones (SZs) can be expected in background electrolytes (BGEs) with a low buffer capacity. The mobilities of this type of SZ (mSZ) could be determined by calculations both based on a mathematical model and by a simulation program. The values of mSZ are increasing for decreasing buffer capacities and lower concentrations of the BGEs. For completely unbuffered BGEs with a pH below 7, the mSZ reached values up to 350×10−9 m2V−1s−1. This value indicates that the existence of this type of SZ originates from migrating hydrogen ions. Although both the mathematical model and simulation program do not consider the influence of the pH of the sample solution, experiments have shown that the pH of the sample solution is also very important. The lower the pH of the sample solution, the larger the mSZ in a specific BGE for cationic SZs. Using completely unbuffered BGEs the hydrogen ions present in the original sample start to migrate freely through the capillary tube with the mobility of a single hydrogen ion and cause stepwise disturbances in the base line of the detector trace. It is remarkable that this type of SZ appears not to affect the electromigration dispersion (EMD) in a strong way and so far only dips could be obtained experimentally.
Large‐volume stacking in capillary electrophoresis using pH hysteresis of the electroosmotic flow in a bare fused‐silica capillary
Authors: Han Ji Hye , Chun Man‐Seog , Riaz Asif , Chung Doo Soo 
Published: January 2005

AbstractFor large‐volume stacking with the electroosmotic flow pump (LVSEP) in capillary electrophoresis of anionic analytes it is required that the electroosmotic mobility (EOM) should be smaller than the magnitudes of the effective mobilities of the analytes. When a fused‐silica capillary is treated with an acidic solution, the silanoate group on the silica surface is neutralized to silanol and the EOM is suppressed. Due to the slow deprotonation equilibrium of the silanol group at an intermediate pH, this reduced EOM can be retained during a number of electrophoresis runs. Using a bare fused‐silica capillary preconditioned with 0.01 M HCl, successful LVSEP at pH 6.0 was achieved for weakly acidic compounds with two orders of magnitude enhancements in the concentration sensitivity. The repeatability in migration times of ten analytes stacked by LVSEP in a single day was excellent with the relative standard deviation (RSD) less than 1% (n = 6). The day‐to‐day repeatability was also excellent with RSD less than 3% (n = 3×6) when the capillary was preconditioned each day.
Performance evaluation of shear links and orthotropic bridge deck panels for the new San Francisco–Oakland Bay Bridge
Authors: Uang Chia‐Ming , Seible Frieder , McDaniel Cole , Chou Chung‐Che 
Published: January 2005

AbstractThis paper presents results from testing and the associated analytical studies of steel shear links and orthotropic bridge decks to support the design of the new East Span for the San Francisco–Oakland Bay Bridge. Cyclic testing of full‐scale built‐up links showed that the specimens were able to reach an inelastic rotation more than twice that which would be produced from a 1500‐year Safety Evaluation Earthquake event. Nevertheless, brittle fracture occurred before the inelastic design rotation capacity, as specified in the AISC Seismic Provisions, was developed. Based on a parametric study, a modification to the welding details was proposed, which proved to be effective in preventing this type of fracture in a subsequent testing program. Monotonic testing of two reduced‐scale orthotropic bridge deck panels, one stiffened with closed ribs and another one with open ribs, also showed that these specimens could develop a compression capacity greater than that which would be produced by the design earthquake. The post‐buckling behavior was associated with the buckling direction and the type of ribs. Copyright © 2005 John Wiley & Sons, Ltd.
Vibrational computations beyond the harmonic approximation: Performances of the B3LYP density functional for semirigid molecules
Authors: Carbonniere Philippe , Lucca Tecla , Pouchan Claude , Rega Nadia , Barone Vincenzo 
Published: January 2005

AbstractThe performances of the B3LYP density functional in the computation of harmonic and anharmonic frequencies were tested using 14 standard basis sets of double and triple zeta quality for a set of semirigid molecules containing from 4 to 12 atoms. The quality of the results is assessed by comparison with the most reliable computations available in the literature. The study reveals that the relatively cheap 6‐31+G(d,p) basis set performs a very good job for harmonic frequency calculations and that B3LYP anharmonicities are in close agreement with the reference values irrespective of the basis set used. On these grounds “hybrid force fields” are proposed to achieve the best compromise between computer time and quality of the results. © 2005 Wiley Periodicals, Inc. J Comput Chem 26: 384–388, 2005
The Influence of the Rubber Carboxyl Functionality on the Processability and Properties of Solid Rubber Modified Epoxy Mixtures
Authors: Dispenza Clelia , Spadaro Giuseppe , McGrail Patrick T. 
Published: January 2005

AbstractSummary: A high molecular weight, carboxyl functionalised solid rubber was added to an epoxy resin‐aromatic amino system developed for autoclave curing of honeycomb core composite structures. The achievement of an optimal balance of viscous flow and viscoelasticity of the resin, by controlling the nature and extent of cross‐linking of the functionalised rubber, was proposed as a route to void‐free honeycomb skins. The aim of the present investigation is to understand how the concentration of carboxylic groups of the rubber, prereacted with one of the epoxy monomers, affects the matrix resin flow properties. The concentration of carboxyl groups was changed by reacting them with a monofunctional epoxy resin. Dynamic shear viscosity profiles varying frequency, temperature and as function of time during isothermal cure have been determined for blends with differently functionalised rubbers. Carbon fibre wettability and laminate consolidation quality have been evaluated, making composite samples according to conventional prepregging and autoclave curing processes, through electron microscopy of fracture surfaces from transverse flexural strength tests.Loss factor and storage modulus from dynamic‐mechanical torsion analysis for PWE0 blend. Loss factor and storage modulus for Nipol 1072 are reported for comparison.magnified imageLoss factor and storage modulus from dynamic‐mechanical torsion analysis for PWE0 blend. Loss factor and storage modulus for Nipol 1072 are reported for comparison.
Expandable Graphite Systems for Phosphorus‐Containing Unsaturated Polyester, 2
Authors: Shih Yeng‐Fong 
Published: January 2005

AbstractSummary: A series of flame‐retardant‐containing unsaturated polyesters have been developed. The flame retardants include expandable graphite (EG) and phosphorous‐containing materials (ammonium polyphosphate (APP) and triphenyl phosphate (TPP)). The flame‐retardant properties of these samples were investigated by thermogravimetric analysis (TGA), limiting oxygen index (LOI), and UL‐94 tests. Moreover, the kinetic parameters of these flame‐retardant‐containing unsaturated polyesters were calculated by the Coats and Redfern method, the Ozawa method, and temperature modulated thermogravimetric analysis (MTGA). The differences and relationship among different analytical methodologies were investigated. Pyrolysis gas chromatography mass spectrometry (Py/GC/MS) was also used to investigate the pyrolysis products of the samples.Activation energy vs. conversion curves for various samples (Ozawa method).magnified imageActivation energy vs. conversion curves for various samples (Ozawa method).
Re‐Plasticization by Confinement During Annealing Induced Phase Separation in Polycarbonate/Phthalate Plasticized Films
Authors: Tuteja Bindu , Khan Ferdous , Sundararajan Pudupadi 
Published: January 2005

AbstractSummary: It is common practice during the analysis using optical microscopy to place the sample on a microscope slide and cover it with a cover slide or another microscope slide. The sample is thus sandwiched or “confined” between two glass surfaces. Such a set up is used in all disciplines of science to study the changes in the structure and morphology of materials caused by annealing and other processes in situ. We describe a case of annealing induced phase separation in polycarbonate plasticized with diphenyl terephthalate and diphenyl isophthalate, which unexpectedly showed a significant difference between the confined configuration as defined above and the “unconfined” state. This was traced to the large depression of the melting point of the plasticizer in the polymer. When annealing was performed with the composite film confined between two glass slides, with the temperatures used here, the phase‐separated small molecule melts and re‐plasticizes the polymer. As a result, there was no increase (recovery) of the Tg of the polymer with annealing temperature. Such a confinement (or overcoating) could be a route to maintaining the Tg of the composite in multi‐layer devices, even if phase separation occurs during the operation of the device. However, when the covering glass slide was not used, sublimation of the plasticizer occurred, and the normal Tg recovery was seen. This is also the first reported case of re‐plasticization of the polymer upon annealing in such a confined state. We also note significant differences in the phase separation behaviour of the terephthalate and isophthalate configurations.Optical micrographs of films annealed at 130 °C for 2 h: left: DPTP/BPAPC: 10/90, confined; right: DPTP/BPAPC: 10/90, unconfined.magnified imageOptical micrographs of films annealed at 130 °C for 2 h: left: DPTP/BPAPC: 10/90, confined; right: DPTP/BPAPC: 10/90, unconfined.
Directly Fabricating Monolayer Nanoparticles on a Polymer Surface by UV‐Induced MMA/DVB Microemulsion Graft Polymerization
Authors: Wang Yongxin , Zhong Wenbin , Jiang Nan , Yang Wantai 
Published: January 2005

AbstractSummary: A sequential two‐step method was successfully used for the photografting of methyl methacrylate/1,2‐divinylbenzene (MMA/DVB) microemulsion onto the surface of a poly(propylene) (PP) film. Atomic force microscopy (AFM) images showed that nanoparticles with a cross‐section diameter of 60 nm were directly grafted onto the substrate's surface. Environment scanning electron microscope (ESEM) images proved that the particles formed just a single layer on the surface. The dormant groups on the nanoparticles' surface were a potential factor in the evolution of single layer into multilayer nanoparticles.The surface morphology of a PP film after being grafted with a MMA/DVB microemulsion. Nanoparticles (about 60 nm in size) are clearly tethered onto the substrate's surface with just one layer.imageThe surface morphology of a PP film after being grafted with a MMA/DVB microemulsion. Nanoparticles (about 60 nm in size) are clearly tethered onto the substrate's surface with just one layer.
Myocytes positive for in situ markers for DNA breaks in human hearts which are hypertrophic, but neither failed nor dilated: a manifestation of cardiac hypertrophy rather than failure
Authors: Koda Masahiko , Takemura Genzou , Kanoh Motoo , Hayakawa Kenji , Kawase Yukinori , Maruyama Rumi , Li Yiwen , Minatoguchi Shinya , Fujiwara Takako , Fujiwara Hisayoshi 
Published: January 2005

AbstractThe significance of DNA breaks reported in failing hearts is controversial, although they may suggest myocyte apoptosis and may thus be responsible for the progression of heart failure. This study attempted to check the validity of the in situ markers for DNA breaks for detecting myocyte death and to evaluate separately two factors, failure or hypertrophy, crucial for DNA breaks in pathological human hearts. In the autopsy study, myocytes showed positivity for in situ nick end‐labelling (TUNEL) and of Taq and Pfu polymerase‐based in situ ligation assays not only in dilated cardiomyopathy (DCM, n = 9) with failure, but also in hypertrophic cardiomyopathy (HCM, n = 8) and hypertensive heart disease (HHD, n = 4) without failure. There was a significant correlation between each in situ marker and heart weight. The incidence of TUNEL‐positive myocytes always exceeded that seen in in situ ligation assays. In addition, there were significant correlations between the in situ markers and the expression of the proliferating cell nuclear antigen (PCNA) and of the spliceosome component of 35 kD (SC‐35). Similarly, in the left ventricular biopsy study using 23 DCM, 21 HCM, 11 HHD, and 13 non‐hypertrophic hearts, the incidence of the in situ markers showed significant correlations with the left ventricular mass index and myocyte size, but not with cardiac function and dilatation. Positivity of myocytes for in situ markers for DNA breaks, such as TUNEL and in situ ligation assays, may be an epiphenomenon accompanying cardiac hypertrophy, but not myocyte death in pathological human hearts. Copyright © 2003 John Wiley & Sons, Ltd.
Risk and protective factors for poor school adjustment in lesbian, gay, and bisexual (LGB) high school youth: Variable and person‐centered analyses
Authors: Murdock Tamera B. , Bolch Megan B. 
Published: January 2005

AbstractThis study examined the relations between school climate and school adjustment among 101 lesbian, gay, and bisexual (LGB) high school students and the moderating influence of social support on those relations. Students completed surveys to assess three aspects of the school climate (the school's exclusion/inclusion of LGB people, personal victimization in school for being LGB, and social support from teachers) as well as social support from family and close friends. Criterion variables were GPA, school belonging, and discipline problems. School climate variables explained significant amounts of variance in all criterion variables, after controlling for prior GPA, and there were no moderating effects of parent or friend support. Cluster analyses revealed one small group (n= 14) of highly vulnerable youth who were the least adjusted, most victimized, and least supported. Implications for teachers, counselors, and future research are discussed. © 2005 Wiley Periodicals, Inc. Psychol Schs 42: 159–172, 2005.
Synthesis and photochromic reaction of 1,2‐diphenylperfluorocyclopentenes
Authors: Takeshita Michinori , Ogawa Miwa , Miyata Keisuke , Yamato Takehiko 
Published: January 2005

AbstractThe synthesis and photochromic reaction of 1,2‐diphenylperfluorocyclopentenes are reported. Upon UV irradiation, hexane solutions of 1,2‐diphenylperfluorocyclopentenes afforded red solution of dihydrophenanthrenes, which gradually give the initial 1,2‐diphenylperfluorocyclopentenes at room temperature thermally or under irradiation with visible light. The activation energies for the thermal isomerization of the dihydrophenanthrenes are estimated. Copyright © 2003 John Wiley & Sons, Ltd.
Efficient room temperature continuous‐wave operation of an Yb3+:Sc2O3crystal laser at 1041.6 and 1094.6 nm
Authors: Liu J. , Rico M. , Griebner U. , Petrov V. , Peters V. , Petermann K. , Huber G. 
Published: January 2005

AbstractAn Yb‐doped Sc2O3crystal grown by the heat exchanger method provided extremely high pump (62.2%) and slope (72.7%) efficiencies in a continuous‐wave (cw) laser operating either at 1041.6 or 1094.6 nm depending on the output coupling. Maximum powers of 1.55 and 1.35 W, respectively, were achieved by Ti:sapphire laser pumping without special cooling. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Local characteristics of the electronic structure of MgO: LCAO and plane‐wave calculations
Authors: Evarestov R. A. , Smirnov V. P. , Tupitsyn I. I. , Usvyat D. E. 
Published: January 2005

AbstractLinear combinations of atomic orbitals and plane‐wave calculations of the electronic structure of the ionic crystal MgO were performed. Local characteristics of the electronic structure of this crystal are obtained using the traditional approaches and the method based on Wannier‐type atomic orbitals (WTAOs). It is demonstrated that the results of the conventional methods for chemical bonding analysis in MgO are contradictory and unreasonable. On the contrary, the results of the WTAO method for both types of the basis correctly exhibit the ionic nature of chemical bonding in this crystal. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
The Stark effect in atomic Rydberg states through a quantum defect approach
Authors: Menéndez J. M. , Martín I. , Velasco A. M. 
Published: January 2005

AbstractA basis set of quantum defect orbitals (QDOs) has been adopted for the diagonalization of the Hamiltonian matrix of nonhydrogenic atoms in the presence of an external electric field, so that the Stark structure of the Rydberg states has been possible to determine. The presently obtained Stark maps are in excellent agreement with those resulting from theory and experiment, as reported in the literature for a few representative atoms. The adequacy of the Stark quantum defect orbital (SQDO) procedure for accurately dealing with properties related to the Stark effect in atoms is suggested. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Catch-Up and Competitiveness in China: The Case of Large Firms in the Oil Industry. By Jin Zhang. [London and New York: RoutledgeCurzon, 2004. xx +230 pp. $114.95. ISBN 0-415-33321-0.]
Authors: Downs Erica S. 
Published: January 2005

Jin Zhang's study of the oil industry examines the challenges China faces in its efforts to create indigenous firms capable of competing with the world's leading companies. The task of catching up with the international oil giants is daunting for China's oil firms not only because the global oil business is one with a high cost of entry in terms of experience (the top companies have been around the longest), but also because, as Zhang observes, they are chasing a moving target. The international oil industry of today is fundamentally different from that of the 1980s and early 1990s when the Chinese government embarked on its tortuous path to reform China's oil sector. The mergers that occurred between the world's major oil companies in the late 1990s created a smaller group of much larger companies at the apex of the international oil industry, greatly expanding the gap between these companies and China's aspiring giants. Furthermore, many state-owned firms have disappeared from the ranks of the world's leading oil companies, a development that runs counter to China's strategy of catapulting its “national champions” into this peer group.Zhang illustrates the magnitude of these challenges facing China's aspiring oil giants through her systematic comparison of BP and Shell with PetroChina and Sinopec, the partially-privatized subsidiaries of the state-owned China National Petroleum and Natural Gas Group Company (CNPC) and Sinopec Group respectively, on a number of key business and organizational criteria. At first glance, the lead these “super majors” have over the Chinese companies in terms of business capabilities such as financial performance, technological prowess and the quality of their reserve portfolios, is more striking than the advantage the super majors have in organizational capabilities such as structure and leadership. Indeed, the organizational structures of PetroChina and Sinopec resemble those of BP and Shell. Zhang notes, however, that beneath these superficial similarities lie two critical differences between the Chinese companies and the super majors, differences that arguably constitute the greatest obstacle to the Chinese oil companies “catching up” with the super majors.
A molecular marker of leaf rust resistance gene Lr37 in wheat
Authors: Li-Rong Zhang , Da-Qing Xu , Wen-Xiang Yang , Da-Qun Liu 
Published: January 2005

AbstractInter-simple sequence repeat (ISSR) analysis was carried out in Thatcher, 20 near-isogenic lines (NILs) containing respectively different genes conferring resistance against wheat leaf rust (Puccinia recondite f.sp. tritici), three materials carrying Lr37 and three materials without Lr37. All of the 100 ISSR primers showed clear amplification products. Two of them amplified the polymorphic DNA bands in the NILs, Thatcher and Lr37/6*Thatcher. The polymorphic bands were named UBC812-1200 and UBC848-700, respectively. The three materials with and without Lr37 were detected in tests using the two primers UBC812 and UBC848. Results also showed that only band UBC812-1200 was amplified in all resistant and absent in all susceptible materials. This suggests that UBC812-1200 marker is linked to the resistance gene Lr37. The genetic linkage of the polymorphic marker with Lr37 was tested using a segregating F2 population (128 plants) derived from a cross between the leaf rust-resistant Lr37/6*Thatcher and the susceptible cultivar Thatcher. The ISSR marker UBC812-1200 showed co-segregation to the Lr37 resistance gene. It could be used in molecular marker-assisted selection in a wheat breeding programme for leaf rust resistance.