bluuebunny/crossref_metadata_2025_split huggingface dataset:
On a current mechanism in Ta2O5 thin films
Authors: Pipinys Povilas , Rimeika Alfonsas 
Published: August 2008

Abstract
Electrical conduction in the temperature range of 120–370 K has been studied in sandwiched structures of Al/Ta2O5/Si. The tantalum oxide films were prepared by evaporation of tantalum on a p-Si crystal substrate, followed by oxidation at a temperature of 600°C. The temperature-dependent current-voltage (I–V) characteristics are explained on the basis of a phonon-assisted tunnelling model. The same explanation is given for I–V data measured on Ta2O5 films by other investigators. From the comparison of experimental data with theory the density of states in the interface layer is derived and the electron-phonon interaction constant is assessed.
The magnetic field dependence of the deformation potential materials in the square well confinement potential
Authors: Sug Joung , Lee Su , Kim Jong 
Published: August 2008

Abstract
We study the optical Quantum Transition Line Shapes (QTLS) which show the absorption power and the Quantum Transition Line Widths (QTLW) of electron-deformation potential phonon interacting systems. In order to analyze the quantum transition, we compare the magnetic field dependencies of the QTLWand the QTLS on two transition processes, namely the intra-Landau level transition process and the inter-Landau level transition process. We apply the Quantum Transport theory (QTR) to the system in the confinement of electrons by square well confinement potential. We use the projected Liouville equation method with Equilibrium Average Projection Scheme (EAPS).
Electronic properties of austenite and martensite Fe-9%Mn alloys
Authors: Uçgun Ercan , Ocak Hamza 
Published: August 2008

Abstract
We calculate the electronic properties of austenite and martensite Fe-9%Mn alloys using the self consistent full-potential linearized-plane-wave method under the generalized gradient approximation full lattice relaxation. By minimizing total-energy, the lattice constants in their ground states were determined. We discuss the total energy dependence of the volume, and density of states (DOS).
One-pot synthesis of xanthene derivatives under solvent-free conditions
Authors: Dabiri Minoo , Azimi Seyyedeh , Bazgir Ayoob 
Published: August 2008

AbstractOne-pot synthesis of aryl-14H-dibenzo[a,j]xanthene and 1,8-dioxo-octahydroxanthene derivatives using montmorillonite K10 as reusable eco-friendly catalyst under solvent-free conditions is described.
Long-term operation of a domestic wastewater treatment plant with membrane filtration
Authors: Dančová Lucia , Bodík Igor , Blšťáková Andrea , Jakubčová Zuzana , Drtil Miloslav 
Published: August 2008

AbstractPossibilities of membrane technology and the use of membrane processes in wastewater treatment were investigated. The main focus was the monitoring of the starting phase of a domestic wastewater treatment plant. Experimental part of the study was realized at the municipal wastewater treatment plant (WWTP) Devínska Nová Ves — Bratislava during the period from February 2005 to September 2006. The system was stable without any external chemical treatment of the membrane modules and the permeate quality was very high. Observed decrease of COD and BOD5 values ranged between 91 % and 98 %. The process of nitrification was very successful considering its high efficiency (> 95 %).
Synthesis and biological activity of a cyclic hexapeptide from Dianthus superbus
Authors: Dahiya Rajiv 
Published: August 2008

AbstractPlant-originated cyclopolypeptide (XIII) was synthesized by coupling of dipeptide Boc-l-asn(bzh)-l-phe-OH and tetrapeptide gly-l-leu-l-ala-l-tyr-OMe followed by cyclization of a linear hexapeptide segment. Structure elucidation of XIII was done on basis of detailed spectral analysis including FTIR, 1H NMR, 13C NMR, FAB MS and elemental analysis. From the results of pharmacological screening, it was concluded that XIII possesses high cytotoxic activity against DLA and EAC cell lines with CTC50 values of 15.1 μM and 18.6 μM, and potent antimicrobial activity against pathogenic fungi C. albicans with MIC of 6 μg mL−1. Moreover, XIII possesses moderate anthelmintic activity against earthworms M. konkanensis, P. corethruses, and Eudrilus sp. at 2 mg mL−1 dose level.
Infrared spectra of Hoffmann-T d-type benzene clathrates
Authors: Aytekin Meryem , Şenyel Mustafa 
Published: August 2008

AbstractSix new title compounds in the form of Cd(cyclobutylamine)2M′(CN)4 · 2G (M′ = Cd or Hg; G = benzene, 1,2-dichlorobenzene, or 1,3-dichlorobenzene) have been prepared in powder form. Their spectral data were found to be consistent with the structure of the Hofmann-T d-type clathrates.
Synthesis of silsesquioxane nanocomposites
Authors: Smrtka Ondřej , Jančář Josef 
Published: August 2008

AbstractIn order to investigate the effect of presence of well defined nano-sized inorganic particles on the molecular mobility a conformation statistics of polymer chains, well defined polystyrene (PS) and poly(methyl methacrylate) (PMMA) macromolecules containing polyhedral oligomeric silsesquioxanes nanoparticles (POSS) were synthesized by copper-mediated atom transfer radical polymerization (ATRP). Two approaches were used for the synthesis — the first involves POSS as the initiator of ATRP; the second way considers an addition of POSS to the polymer (prepared by ATRP) with an appropriate functional group. Kinetics of polymerization was determined using common analytical methods and it was compared to the polymerizations initiated by low-molecular weight initiators, regarding the polymerization rate, initiation efficiency and polydispersity of the polymer. Efficiency of the initiation with POSS-containing initiators was low, causing remnants of inseparable free POSS in polymer. The second approach bypassed these disadvantages —POSS is connected to the polymer through a pending allyl group using the very efficient hydrosilylation reaction.
Structural and electronic effects involving pyridine rings in 4-methylpyridine Cu4OX6L4 complexes. I. Vibrational spectra of Cu4OBrnCl(6−n)(4-Mepy)4 complexes
Authors: Ondrejovič Gregor , Koman Marian , Kotočová Adela 
Published: August 2008

AbstractGaussian analysis of bands between 500 cm−1 and 600 cm−1 attributed to the $$ \tilde \nu $$ as (Cu4O) stretching vibration of the tetrahedral Cu4O core in Cu4OBrnCl(6−n)(4-Mepy)4 (n = 0–6) complexes showed two bands, symmetry reduction of the T 2 mode of vibration towards the A 1 and E modes and vibrational coupling with an R-sensitive in-plane pyridine ring bending. The Cu-O bond is considered as vibrationally coupled with the Cu-N bond and the pyridine ring through the donor-acceptor vibrational coupling and the corresponding equilibrium charge distribution. The linear correlation between $$ \tilde \nu $$ as(Cu4O) and the number of bromides in Cu4OBrnCl(6−n)(4-Mepy)4 complexes was used for the estimation of partial charges on the 4-Mepy ligands which were positive for the prevailing donors and negative for the prevailing acceptors thus evoking a π-back bonding between the Cu(II) atoms and the 4-Mepy ligands. Correlations involving selected bond lengths and bond angles in the molecular structure of the Cu4OCl6(4-Mepy)4 complex with four symmetrically independent molecules present in the unit cell indicate a symmetry reduction of the T 2 mode of vibration and the π-back bonding between the Cu(II) atoms and the 4-Mepy ligands.
Copper(II) and cobalt(II) hydroxypyridinecarboxylates: Synthesis, crystal structures, spectral and magnetic properties
Authors: Miklovič Jozef , Segľa Peter , Mikloš Dušan , Titiš Ján , Herchel Radovan , Melník Milan 
Published: August 2008

AbstractSynthesis and characterization of six copper(II) and cobalt(II) octahedral complexes [M(6-OHpic)2(H2O)2] (6-OHpic is 6-hydroxypicolinato), [M(2-OHnic)2(H2O)2] (2-OHnic is 2-hydroxynicotinato), [Cu(6-OHnic)2(H2O)2] (6-OHnic is 6-hydroxynicotinato) as well as [Co(H2O)6](6-OHnic)2 are reported. Their characterization was carried out using elemental analysis, infrared, and magnetic measurements. Based on IR spectra, N,O-coordination of 6-OHpic (via the oxygen atom of the carboxyl group and the nitrogen atom of the pyridine ring), O,O-asymmetrically chelating coordination of the carboxyl groups as well as ionic coordination of 6-OHnic and chelating O,O-coordination (through the oxygen atom of the carboxyl group and the oxygen atom of the amide group) of keto(amide) tautomer of 2-OHnic were supposed. Moreover, crystal structures of 2-OHnicH and the complex [Co(2-OHnic)2(H2O)2]) were determined by X-ray single crystal structure analysis. The system of hydrogen bonds predominantly stabilizes the keto(amide) tautomer of both 2-hydroxynicotinic acid and 2-OHnic anion in the cobalt(II) complex. Intermolecular hydrogen bonds (between the oxygen atom of the amide group and the hydrogen atom of the NH group) interconnect two neighbouring molecules of 2-OHnicH forming dimers. Cobalt(II) in complex [Co(2-OHnic)2(H2O)2] has nearly a regular compressed tetragonal bipyramidal arrangement.
Computer-aided process design of affinity membrane adsorbers: a case study on antibodies capturing
Authors: Beijeren Peter , Kreis Peter , Hoffmann Achim , Mutter Martina , Sommerfeld Sven , Bäcker Werner , Górak Andrzej 
Published: August 2008

AbstractDesign of affinity membrane adsorbers for the purification of biomolecules requires a consideration of loading, washing, and elution. Modelling and simulation of membrane adsorbers in literature is, however, strongly focused on the loading step. Therefore, in this work, a complete process model which takes all the different steps into account was developed. Breakthrough experiments in which human IgG was captured onto and eluted from Sartobind Protein A downscale modules were used for model validation and for estimation of the required model parameters. The experimentally observed breakthrough curves were independent of the applied flow rate and from these results linear correlations between lumped kinetic parameters and linear velocity were determined. During elution, desorption was best described by an irreversible reaction of first order in H+ concentration. Applicability of the developed model to computer-aided design was illustrated through a process analysis study in which the influence of the amount of loaded protein per cycle on the process yield and productivity was investigated.
Improvement of paper strength via surface application of sugar beet pectin
Authors: Gigac Juraj , Fišerová Mária , Rosenberg Michal 
Published: August 2008

AbstractThe influence of surface-applied original and enzymatically-modified sugar beet pectin on strength properties of fluting, coating base paper, and core board was investigated. The effect was compared with the application of commercial strength-increasing agents. With increasing the polymer uptake, measured strength of paper increased. Original sugar beet pectin increased the strength properties of papers, at the same uptake of polymer, to a higher extent than oxidised potato starch or modified grain flour, while the effect of enzymatically-modified sugar beet pectin was the lowest. For the same increase of paper strength, a several times higher uptake of enzymatically-modified sugar beet pectin was required when compared with the original pectin, oxidised potato starch, or modified grain flour.
Pentanuclear heterobimetallic 3d-4f complexes of Ln2M3-type — structure and magnetism
Authors: Siebold Matthias , Korabik Maria , Schilde Uwe , Mrozinski Jerzy , Strauch Peter 
Published: August 2008

AbstractFrom a series of pentanuclear, heterobimetallic complexes of the general composition [{Ln(H2O)n}2{Ni(dto)2}3] · xH2O, four complexes (Ln = Gd(III) with n = 4; Ln = Dy(III), Ho(III), or Er(III), with n = 5; x = 9–12; dto = 1,2-dithiooxalate) were studied due to their large magnetic moments (up to 14.65 B.M.). The magnetic properties of these complete series were measured at room temperature and the temperature dependent magnetic properties of the complexes Gd2Ni3, Dy2Ni3, Ho2Ni3, and Er2Ni3 were studied at room temperature down to 1.8 K. Whereas the intramolecular metal-metal distances were rather long (Ni1-Ni2: 11.0–11.5 Å; Ln-Ni: 6.0–6.3 Å), relatively short intermolecular metal-metal distances (Ni1-Ni2′: 3.5 Å; Er-Er′: 6.0 Å) were found in the crystal lattice, giving rise to weak intermolecular metal-metal interactions. These weak spin interactions were also supported by the EPR spectrum of a powdered sample of the diamagnetically undiluted Gd2Ni3 complex.
Solution properties of iron(III) complexes with 5-fluorosalicylic acid — spectra, speciation, and redox stability
Authors: Šípoš Rastislav , Šima Jozef , Tarapčík Pavol , Gyurcsik Béla 
Published: August 2008

AbstractIron(III)-5-fluorosalicylic acid systems were investigated in water by pH potentiometry combined with UV-VIS spectrophotometry. The data revealed that stable aquated mono-, bis-, and tris(5-fluorosalicylato) iron(III) complexes are formed together with their monohydroxo and dihydroxo analogues. The stability constants of all present iron(III) species were calculated. Based on pH and the metal: ligand ratio dependent distribution of the species, electronic absorption spectra of the complexes in the visible region were obtained. Redox stability was monitored as an ability to undergo both spontaneous and photoinduced reduction of iron(III) to iron(II). Complexes do not undergo any redox changes when in dark neither in methanol nor in water. While aqueous solutions of complexes are stable under the influence of incident visible radiation, steady-state irradiation of the methanolic systems by visible light led to photoreduction of iron(III) to iron(II), the quantum yield of iron(II) photoformation was determined.
Reaction of lead ions with hydroxylapatite granules
Authors: Hadioui Madjid , Sharrock Patrick , Mecherri Mohamed-Oimar , Brumas Véronique , Fiallo Marina 
Published: August 2008

AbstractIn the effort to improve the performance of hydroxylapatite (HA) in removing lead ions from aqueous solutions, millimeter-sized granules with 50 % porosity were synthesized. Such HA particles, after drying at 100°C, or heating at 800°C or 1100°C, exhibited the specific surface areas of 50 m2 g−1, 25 m2 g−1, and 5 m2 g−1, respectively. It was found that heavy metal sorption capacity of HAs can be related to their surface area. Non-calcined granules were difficult to handle and easy to crush. Hardened granules showed heavy metal absorption on their outer surfaces. Absorption capacity of sintered HA particles towards lead was lower but adsorbed lead ions were spread inside the porous structure of HA granules more evenly. Under flow conditions, lead ions were captured by HA at a rate of 0.5 mg g−1 min−1. Small lead phosphate aggregates were released from the HA sorbent together with calcium ions. Size of the aggregates depended on the lead concentration and ranged from 1–50 μm in diameter; the aggregates could be removed by ultrafiltration. Results show that porous hardened HA granules can be used as an efficient phosphate source for the immobilization of lead ions from aqueous media. Organic ligands tend to interfere with the water purification procedure.
Water Pollution Risk
Authors: El‐Shaarawi Abdel H. 
Published: August 2008

AbstractWater pollution risk is concerned with assessing the impact of existing and future hazards that are associated with the beneficial uses of water. The focus of this article is on risks to human health due to exposure to water pollution. Some important statistical issues involved in the management of risk are discussed based on two pollution types: persistent toxic substances and microbiological contamination.
Gender, precarious work, and chronic diseases in South Korea
Authors: Kim Il‐Ho , Khang Young‐Ho , Muntaner Carles , Chun Heeran , Cho Sung‐Il 
Published: August 2008

AbstractObjectiveIn view of the growing number of nonstandard workers in South Korea, this study examined whether nonstandard workers reported poorer health compared to standard workers and assessed whether there were gender differences in the association between employment status and chronic health outcomes.MethodData were taken from a representative‐weighted sample of 1,563 men and 1,045 women aged 20–64, from the 2001 National Health and Nutrition Examination Survey. Nonstandard employment included part‐time work, temporary work, and day labor. Self‐rated health and self‐reported chronic disease conditions were used as health measures.Main ResultsNonstandard employment was significantly associated with higher risk of self‐rated health and chronic conditions after adjusting for socioeconomic position (education, occupational class, and income) and health behaviors (cigarette smoking, alcohol consumption, regular exercise, and health examinations). However, the pattern in the relation between nonstandard work and specific health problems greatly differed by gender. Among men, nonstandard work arrangements were significantly associated with musculoskeletal disorders (OR 1.97, 95% CI 1.24–3.19) and liver disease (OR 2.83, 95% CI 1.27–6.32). Among women, nonstandard employment was related to mental disorders (OR 3.25, 95% CI 1.40–7.56).ConclusionThe findings clearly indicate the need for further study of the observed associations, particularly prospective and analytical studies. Am. J. Ind. Med. 51:748–757, 2008. Published 2008 Wiley‐Liss, Inc.
Exploring the potential of video technologies for collaboration in emergency medical care: Part I. Information sharing
Authors: Sonnenwald Diane H. , Söderholm Hanna M. , Manning James E. , Cairns Bruce , Welch Greg , Fuchs Henry 
Published: August 2008

AbstractWe are investigating the potential of 3D telepresence, or televideo, technology to support collaboration among geographically separated medical personnel in trauma emergency care situations. 3D telepresence technology has the potential to provide richer visual information than current 2D videoconferencing techniques. This may be of benefit in diagnosing and treating patients in emergency situations where specialized medical expertise is not locally available. The 3D telepresence technology does not yet exist, and there is a need to understand its potential before resources are spent on its development and deployment. This poses a complex challenge. How can we evaluate the potential impact of a technology within complex, dynamic work contexts when the technology does not yet exist? To address this challenge, we conducted an experiment with a posttest, between‐subjects design that takes the medical situation and context into account. In the experiment, we simulated an emergency medical situation involving practicing paramedics and physicians, collaborating remotely via two conditions: with today's 2D videoconferencing and a 3D telepresence proxy. In this article, we examine information sharing between the attending paramedic and collaborating physician. Postquestionnaire data illustrate that the information provided by the physician was perceived to be more useful by the paramedic in the 3D proxy condition than in the 2D condition; however, data pertaining to the quality of interaction and trust between the collaborating physician and paramedic show mixed results. Postinterview data help explain these results.
Exploring the potential of video technologies for collaboration in emergency medical care: Part II. Task performance
Authors: Söderholm Hanna M. , Sonnenwald Diane H. , Manning James E. , Cairns Bruce , Welch Greg , Fuchs Henry 
Published: August 2008

AbstractWe conducted an experiment with a posttest, between‐subjects design to evaluate the potential of emerging 3D telepresence technology to support collaboration in emergency health care. 3D telepresence technology has the potential to provide richer visual information than do current 2D video conferencing techniques. This may be of benefit in diagnosing and treating patients in emergency situations where specialized medical expertise is not locally available. The experimental design and results concerning information behavior are presented in the article “Exploring the Potential of Video Technologies for Collaboration in Emergency Medical Care: Part I. Information Sharing” (Sonnenwald et al., this issue). In this article, we explore paramedics' task performance during the experiment as they diagnosed and treated a trauma victim while working alone or in collaboration with a physician via 2D videoconferencing or via a 3D proxy. Analysis of paramedics' task performance shows that paramedics working with a physician via a 3D proxy performed the fewest harmful interventions and showed the least variation in task performance time. Paramedics in the 3D proxy condition also reported the highest levels of self‐efficacy. Interview data confirm these statistical results. Overall, the results indicate that 3D telepresence technology has the potential to improve paramedics' performance of complex medical tasks and improve emergency trauma health care if designed and implemented appropriately.
Robust tracking problem for continuous time stochastic uncertain systems
Authors: Yoon Myung‐Gon , Ugrinovskii Valery A. 
Published: August 2008

AbstractWe propose a finite‐horizon robust minimax tracking controller design method for time‐varying continuous time stochastic uncertain systems. The uncertainty in the system is characterized by a set of probability measures under which stochastic noises, driving the system, are defined. A minimax optimal tracking controller is derived from the solution of a risk‐sensitive linear quadratic Gaussian control problem. Also a numerical example is presented to illustrate the characteristics of proposed tracking controller. Copyright © 2008 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Sliding‐mode control of a three‐degrees‐of‐freedom nanopositioner
Authors: Shen Jing‐Chung , Jywe Wen‐Yuh , Liu Chien‐Hung , Jian Yu‐Te , Yang Jeffrey 
Published: August 2008

AbstractThis paper presents the sliding‐mode control of a three‐degrees‐of‐freedom nanopositioner (Z, θx, θy). This nanopositioner is actuated by piezoelectric actuators. Capacitive gap sensors are used for position feedback. In order to design the feedback controller, the open‐loop characteristics of this nanopositioner are investigated. Based on the results of the investigation, each pair of piezoelectric actuators and corresponding gap sensors is treated as an independent system and modeled as a first‐order linear model coupled with hysteresis. When the model is identified and the hysteresis nonlinearity is linearized, a linear system model with uncertainty is used to design the controller. When designing the controller, the sliding‐mode disturbance (uncertainty) estimation and compensation scheme is used. The structure of the proposed controller is similar to that of a proportional integral derivative controller. Thus, it can be easily implemented. Experimental results show that 3‐nm tracking resolution can be obtained. Copyright © 2008 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society