bluuebunny/crossref_metadata_2025_split huggingface dataset:
Selective Hydrogenation of 1‐Butene Rich Cuts: the Impact of the Intraparticle Diffusion Limitations on the Selectivity
Authors: Bressa S.P. , Alves J.A. , Martínez O.M. , Barreto G.F. 
Published: July 2003

AbstractThe impact of intraparticle diffusion limitations on the selectivity of an industrial reactor for selective hydrogenation of 1‐butyne and 1,3‐butadiene contained in 1‐butene rich cuts was evaluated. To this end, a simple model of a trickle‐bed reactor was employed and actual process operating conditions were chosen. A kinetic model was chosen whose parameters correspond to a commercial catalyst. These parameters were calculated from experiments conducted under industrial operating conditions. The complex diffusion and reaction phenomena occurring inside catalyst pellets placed at different depths of the reactor are comprehensively described. 1‐Butene losses in the range 20–30 %, which are usual in commercial plants, were predicted. It was concluded that the operating pressure is crucial for enhancing process selectivity.
The Droplet Population Balance Model – Estimation of Breakage and Coalescence
Authors: Simon M. , Schmidt S.A. , Bart H.‐J. 
Published: July 2003

AbstractA droplet population balance model is employed in order to describe the hydrodynamic behavior of solvent extraction columns. This model describes the axial change of local column holdup and local droplet size distributions due to the basic phenomena, like droplet rising, axial dispersion, droplet breakage and coalescence. In order to reduce experimental efforts, single and swarm droplet experiments in small lab‐scale devices were performed. For this, a rotating disc contactor (RDC) with one compartment and a Venturi tube were used to investigate droplet breakage and droplet coalescence. In case of breakage the experiments were made for different droplet sizes at different rotor speeds for the EFCE system toluene/water, whereas the investigations of the coalescence phenomena depending on droplet size and holdup were done with the EFCE system n‐butylacetate/water.
Metallobiliverdin Radicals—DFT Studies
Authors: Szterenberg Ludmiła , Latos‐Grażyński Lechosław , Wojaczyński Jacek 
Published: July 2003

AbstractSeveral aspects of the molecular and electronic structure of biliverdin derivatives have been studied using density functional theory (DFT). The calculations have been performed for complexes of trianion (BvO2)3− and dianion [BvO(OH)]2−, derived from two tautomeric forms of biliverdin, BvO2H3 and [BvO(OH)]H2, with redox innocent metal ions: lithium(I), zinc(II), and gallium(III). One‐electron‐oxidized and ‐reduced forms of each complex (cation and anion radicals) have been also considered. The molecular structures of all species investigated are characterized by a helical arrangement of tetrapyrrolic ligands with the metal ion lying in the plane formed by the two central pyrrole rings. The spin density distribution in four types of metallobiliverdin radicals—[(BvO2.)Mn+]n‐2, [{BvO(OH).}Mn+]n‐1 (cation radicals), [(BvO2.)Mn+]n‐4, [{BvO(OH).}Mn+]n‐3 (anion radicals)—has been investigated. In general, the absolute values of spin density on meso carbon atoms were larger than for the β‐carbon atoms. Sign alteration of spin density has been found for meso positions, and also for the β‐carbon atoms of at least two pyrrole rings. The calculated spin density maps accounted for the essential NMR spectroscopic features of iron biliverdin derivatives, including the considerable isotropic shifts detected for the meso resonances and shift alteration at the meso and β‐positions.
Cover Picture: Role of Temperature in Controlling Performance of Photorefractive Organic Glasses (ChemPhysChem 7/2003)
Authors: Ostroverkhova Oksana , He Meng , Twieg Robert J. , Moerner W. E. 
Published: July 2003

AbstractThe cover picture shows the underlying mechanism and one of the applications of the photorefractive effect, which produces a spatial modulation of the refractive index of a material under nonuniform illumination. As illustrated on the right side, the photorefractive effect begins with light and dark fringes produced by intersecting laser beams, which, in the presence of an applied electric field E0, produce charge separation. The mobile charges (primarily holes) move and eventually trap in dark regions, leading to a space–charge electric field (green). This field produces a refractive index change, that is, a hologram that can diffract light. A key feature of the effect is that it leads to asymmetric energy transfer between the two beams incident on the material. An application of this effect is image amplification, which is demonstrated on the top left side of the picture where the image of the number 5, carried by a weak beam, is amplified in the presence of a strong beam. Among the best photorefractive materials developed thus far are organic, amorphous glasses, the properties of which depend critically on the glass transition temperature (Tg) and photoconductivity (σph), as well as polarizability anisotropy (Δα) and hyperpolarizability (β) of the molecules. The picture shows the structure of the photoconductive, nonlinear optical chromophore DCDHF‐6 that forms a high‐performance low‐molecular weight photorefractive glass. The detailed properties of several photorefractive glasses containing DCDHF derivatives are described in the article by Ostroverkhova et al. on page 732.
The Electrochemically Initiated Reaction of Sulfide with N,N‐Diethyl‐p‐phenylenediamine in Dimethylformamide. Part II: Implications for Sensing Strategies
Authors: Giovanelli Debora , Lawrence Nathan S. , Klymenko Oleksiy V. , Jiang Li , Jones Timothy G. J. , Compton Richard G. 
Published: July 2003

AbstractThe electrochemically initiated reaction of p‐phenylenediamines with sulfide in aqueous media is well documented. We now report the adaptation of this chemistry into nonaqueous media. This is critically appraised as a means of detecting sulfide. The electrochemically initiated reaction of N,N‐diethyl‐p‐phenylenediamine with sulfide is shown at both macro‐ and platinum microdisk electrodes with quantitative detection of sulfide produced by means of the enhanced currents observed upon its addition. The linear detection range for sulfide is dependent on the concentration of N,N‐diethyl‐p‐phenylenediamine present with a linear range from 28–3290 μM and a limit of detection of 22 μM achievable. This represents a large increase compared to that found previously in aqueous media and offers the prospect of more ready applications in high temperature systems.
Electrochemical Quartz Crystal Impedance Study of Glucose Oxidation on a Nickel Hydroxide Modified Au Electrode in Alkaline Solution
Authors: Xiang CanHui , Xie QingJi , Yao Shouzhuo 
Published: July 2003

AbstractThe electrochemical quartz crystal impedance (EQCI) technique has been applied to investigate glucose oxidation on bare and Ni(OH)2‐modified Au electrodes in 0.2 mol L−1 KOH aqueous solution. The EQCI responses suggest different contributions of H+‐release and OH−‐incorporation reactions of the Ni(OH)2‐film redox process in 0.2 mol L−1 aqueous KOH at different potentials. Glucose adsorption on the Ni(OH)2‐modified Au electrode was studied. A mechanism for potential cyclic redox process of glucose at Ni(OH)2‐modified Au electrode is suggested, mainly based on a comparative EQCI analysis with direct glucose oxidation on bare gold and glucose ad‐/desorption on Ni(OH)2 film.
Quantitative capillary zone electrophoresis of inorganic anions
Authors: Paull Brett , King Marion 
Published: July 2003

AbstractDespite the availability of commercial capillary electrophoresis systems for over ten years, where quantitative analysis is required, capillary zone electrophoresis (CZE) has often failed to replace ion chromatography as the method of choice for a large number of analytes, not least inorganic anions. To investigate the reasons for this apparent failing, a review is presented of work that has been carried out to‐date involving the quantitative application of CZE to the determination of inorganic anions in industrial and environmental samples. This review summarizes work both investigating and improving the quantitative aspects of the CZE of inorganic anions. A complete survey of how CZE has been applied to the determination of inorganic anions in real samples is given, including what, if any, analytical performance parameters were investigated and quoted, and if quality assurance data and validation methods were briefly considered, thoroughly investigated or simply ignored.
Capillary electrophoresis determinations of trace concentrations of inorganic ions in large excess of chloride: Soft modelling using artificial neural networks for optimisation of electrolyte composition
Authors: Muzikárcaron; Martin , Havel Josef , Macka Miroslav 
Published: July 2003

AbstractIn this work, using a combination of experimental design (ED) and artificial neural networks (ANN), the composition of a triethanolamine‐buffered chromate electrolyte was optimised for determination of sulphate anions in the presence of high chloride excess. The optimal electrolyte, allowing a baseline‐resolved separation of sulphate from chloride present in a 1500 multiple excess in less than 170 s, consists of 10 mmol/L CrO3, 2 mmol/L hexamethonium hydroxide, 10% methanol, and triethanolamine added to adjust the pH to 8.0. The method is suitable to a wide concentration range of chloride (4–1757 mg/L) and sulphate (4–590 mg/L) with linear calibration plots (R2 = 0.9937–0.9999). Relative standard deviations are less than 2.0% for both anions for migration times and peak areas. The detection limits (hydrodynamic injection of 1 s) were 0.6 mg/L for sulphate and 0.5 mg/L for chloride. The method was successfully applied to determination of sulphate in mineral waters containing a high chloride concentration and to determination of sulphate traces in an anticancer drug injection preparation containing a physiological level of chloride. It was shown that α‐cyclodextrin as an electrolyte additive has a significant potential for further increasing the separation selectivity for inorganic anions.
Tailoring the separation selectivity of metal complexes and organometallic compounds resolved by capillary electrophoresis using auxiliary separation processes
Authors: Boyce Mary C. , Haddad Paul R. 
Published: July 2003

AbstractThe use of auxiliary separation mechanisms to manipulate the separation selectivity of metal complexes and organometallic species is reviewed. Auxiliary separation mechanisms included in the review are micellar electrokinetic capillary chromatography, ion‐pairing and ion‐exchange electrokinetic chromatography. This paper discusses how these secondary mechanisms can be effectively employed to tailor separation selectivity.
Analysis of inorganic and small organic ions with the capillary electrophoresis microchip
Authors: Willauer Heather D. , Collins Greg E. 
Published: July 2003

AbstractCapillary electrophoresis microchip devices are receiving considerable attention due to their versatility, portability, and sample handling capabilities. This article is a comprehensive review of the analysis of inorganic and small, charged organic species on microchip platforms. The application of conductivity, amperometry, laser‐induced fluorescence, absorbance, and chemiluminescence detection methods are discussed. The potential utilization of these devices for miniaturized analytical systems is described.
Enhancement of detection sensitivity for indirect photometric detection of anions and cations in capillary electrophoresis
Authors: Johns Cameron , Macka Miroslav , Haddad Paul R. 
Published: July 2003

AbstractThis review focuses on the indirect photometric detection of anions and cations by capillary electrophoresis. Special emphasis has been placed on the sensitivity of the technique and approaches taken to enhance detection limits. Theoretical considerations and requirements have been discussed, including buffering, detection sensitivity, separation of cations, and detector linearity. A series of tables detailing highly absorbing probes and the conditions of their use for indirect photometric detection are included.
The importance of capillary electrophoresis, capillary electrochromatography, and ion chromatography in separations of inorganic ions
Authors: Pacáková Věra , Coufal Pavel , Štulík Karel , Gaš Bohuslav 
Published: July 2003

AbstractThe importance of capillary electrophoresis (CE), capillary electrochromatography (CEC), and ion chromatography (IC) in inorganic ion analyses is outlined. Methods for improving the reliability of the CE measurements are briefly described. Selectivity optimization in CE analyses of inorganic cations and anions is discussed. Using the Peakmaster program, CE system peaks (system zones, eigenmobilites) and some important CE parameters, such as effective mobilities, electromigration dispersion, indirect UV, and direct conductivity signals, are predicted and compared with experimental analyses.
Tumor‐inhibiting platinum(II) complexes with aminoalcohol ligands: Comparison of the mode of action by capillary electrophoresis and electrospray ionization‐mass spectrometry
Authors: Hartinger Christian G. , Schluga Petra , Galanski Mathea Sophia , Baumgartner Christian , Timerbaev Andrei R. , Keppler Bernhard K. 
Published: July 2003

AbstractCapillary electrophoresis (CE) was used as an assay for studying the interaction of (SP‐4‐2)‐bis[(R)‐(–)‐2‐aminobutanol)dichloroplatinum(II) (1) and (SP‐4‐2)bis(4‐aminobutanol)dichloroplatinum(II) (2) with guanosine 5'‐monophosphate (GMP). CE kinetic measurements carried out at two physiological pH levels indicated that upon increasing the pH, 1 showed an appreciable change in binding behavior, with the rate of binding increased for more than 10 times as expressed by apparent half‐life values of GMP (6.1 and 62.2 h at pH 6.0 and 7.4, respectively). The rate of GMP binding for 2 remained comparatively less affected by pH (half‐lives of 8.5 and 10.6 h, respectively). Regardless of the nature of platinum complex and pH, the reaction with GMP tends to be decelerated at increased chloride concentrations in solution, this effect being particularly pronounced when changing from 4 mM (intracellular level) to 100 mM (extracellular level). The kinetic differences of platinum complexes were characterized in terms of the respective GMP‐adducts structure, independently identified by means of off‐line electrospray ionization‐mass spectrometry. Also addressed was the interpretation of binding behavior as based on the structural features of the intact complexes, namely differing inclination to intramolecular chelation.
Capillary electrophoresis for short‐chain organic acids and inorganic anions in different samples
Authors: Galli Verónica , García Antonia , Saavedra Luis , Barbas Coral 
Published: July 2003

AbstractThis review article is a comprehensive survey of capillary electrophoresis methods developed for the measurement of short‐chain organic acids and inorganic anions in a wide variety of matrices, such as food and beverages, environmental, industry, and other applications, as well as clinical applications in body fluids such as urine, plasma or cerebrospinal fluid. Details of sample pretreatment and of electrophoretic conditions have been collected in tables, arranged by the type of matrix. Strategies employed for method development for the analysis of these compounds by capillary electrophoresis in real samples are discussed.
Biodegradation of the Water‐Soluble Gasoline Components in a Novel Hybrid Bioreactor
Authors: Goméz‐De‐Jesús A. , Lara‐Rodríguez Á. , Santoyo‐Tepole F. , Juárez‐Ramírez C. , Cristiani‐Urbina E. , Ruiz‐Ordaz N. , Galíndez Mayer J. 
Published: July 2003

AbstractA novel hybrid bioreactor was designed to remove volatile organic compounds from water contaminated with water‐soluble gasoline components, and the performance of this new bioreactor was investigated. It was composed of two biotrickling filter sections and one biofilter section. The liquid phase pollutants were removed by a mixed culture in the biotrickling filter sections and the gas phase pollutants stripped by air injection in the biofilter section. The specific rates of chemical oxygen demand (COD) removal obtained in the reactor were directly proportional to the pollutant‐loading rate. A stable operation of the hybrid bioreactor was attained for long periods of time. The bioreactor had the potential to simultaneously treat a complex mixture of volatile organic compounds, e.g., those present in the water‐soluble fraction of gasoline, as well as the capacity to readily adapt to changing operational conditions, such as an increased contaminant loading, and variations in the airflow rate.
Cognitive therapy for chronic depression
Authors: Riso Lawrence P. , Newman Cory F. 
Published: July 2003

AbstractRecent literature indicates that there are important clinical differences between chronic and non‐chronic depression. This article considers the implications of these differences when conducting cognitive therapy (CT) with chronically depressed patients. CT with chronic patients requires a greater emphasis on combating hopelessness, helplessness, and perfectionism, addressing early life‐adverse experiences, and modifying maladaptive schemas. In addition, the effectiveness of CT may be enhanced by focusing on patients' poor social skills, ineffective reasoning skills, and their depressive identity. The case example presented illustrates CT with a chronically depressed patient. © 2003 Wiley Periodicals, Inc. J Clin Psychol/In Session.
Family therapy and chronic depression
Authors: Keitner Gabor I. , Archambault Richard , Ryan Christine E. , Miller Ivan W. 
Published: July 2003

AbstractIndividuals with chronic depression report significant problems in multiple areas of their family functioning, suggesting the importance of combining family therapy with psychotherapy and pharmacotherapy in the treatment of their depression. We describe a model of family functioning (the McMaster model) and therapy (the Problem‐Centered Systems Therapy of the Family) and its application in the treatment of a young woman with chronic depression. The key elements of the family treatment are a comprehensive assessment of the family, a systematic progression through defined treatment stages, an open, collaborative stance with the family, and a focus on the family's responsibility for change. Family therapy can aid the amelioration of depressive symptoms and improve the ability of family members to deal more effectively with the depression as well as a wider range of problems. © 2003 Wiley Periodicals, Inc. J Clin Psychol/In Session.
Effectiveness of psychotherapy and combination treatment for chronic depression
Authors: Arnow Bruce A. , Constantino Michael J. 
Published: July 2003

AbstractAlthough considerable research has been conducted on the efficacy of psychotherapy for depression, with and without medication, relatively few studies have focused on chronic forms of depression. Approximately 20% of individuals with depression experience episodes that last for two years or longer. We review the controlled research on the effectiveness of treatments separately for dysthymia and chronic major depression, focusing on the practical implications of the research for clinicians. In trials conducted with dysthymics, medication has been superior to psychotherapy, with limited evidence that combined treatment has advantages over medication or psychotherapy alone. In chronic major depression, combined treatment has demonstrated significant superiority over medication or psychotherapy alone. Possible explanations for the discrepant findings among dysthymics and those with chronic major depression are discussed. © 2003 Wiley Periodicals, Inc. J Clin Psychol/In Session.
Genetic characterisation of a hantavirus isolated from a laboratory‐acquired infection
Authors: Shi Xiaohong , McCaughey Conall , Elliott Richard M. 
Published: July 2003

AbstractSeoul (SEO) viruses belong to the Hantavirus genus (family Bunyaviridae), cause the moderate form of haemorrhagic fever with renal syndrome, and have been associated with laboratory‐acquired infections in many countries. To investigate the pedigree of an isolate, designated IR461, which was obtained from a laboratory‐acquired infection in a UK research institute, we determined the nucleotide sequences of the small (S) and medium (M) genome segments. In addition, we determined the sequences of the S segments of two Chinese isolates (R22 and L99) and an American isolate (Tchoupitoulas [TCH]). The S segments range within 1769–1785 nucleotides in length and showed identities of >88% in nucleotide sequence and 97% in amino acid sequence to those of published S segment sequences. The M RNA segment of IR461 is 3651 nucleotides long and shows >84% identity at the nucleotide level and >98% at the amino acid level to the M segments of other SEO viruses. These data confirm that SEO viruses show the least diversity within the Hantavirus genus. Phylogenetic analyses of the sequences showed geographic clustering of the Chinese SEO viruses, and that IR461 was more closely related to SEO viruses isolated in the New World than to those from the Far East. J. Med. Virol. 71:105–109, 2003. © 2003 Wiley‐Liss, Inc.
Differential patterns of human cytomegalovirus gene expression in various T‐cell lines carrying human T‐cell leukemia‐lymphoma virus type I: Role of tax‐activated cellular transcription factors
Authors: Beck Zoltán , Bácsi Attila , Liu Xiangdong , Ebbesen Peter , Andirkó István , Csoma Eszter , Kónya József , Nagy Etelka , Tóth Ferenc D. 
Published: July 2003

AbstractReplication of human cytomegalovirus (HCMV) was investigated in various T‐cell lines expressing the tax gene product of human T‐cell leukemia‐lymphoma virus type I (HTLV‐I). Differential patterns of HCMV replication were found in HTLV‐I‐carrying cell lines. HCMV gene expression was restricted to the immediate‐early genes in MT‐2 and MT‐4 cells, whereas full replication cycle of the virus was observed in C8166‐45 cells. Productive HCMV infection induced a cytopathic effect resulting in the lysis of infected cells. The results of electrophoretic mobility shift assay (EMSA) showed high levels of NF‐κB‐, CREB/ATF‐1‐, and SRF‐specific DNA binding activity in all Tax‐positive cell lines. In contrast, SP1 activity could be detected only in C8166‐45 cells. Using an inducible system (Jurkat cell line JPX‐9), a dramatic increase in NF‐κB, CREB/ATF‐1, SRF, and SP1 binding activity, as well as productive HCMV infection, were observed upon Tax expression. Overexpression of SP1 in MT‐2 and MT‐4 cells converted HCMV infection from an abortive to a productive one. These data suggest that the stimulatory effect of Tax protein on HCMV in T cells is accomplished through at least five host‐related transcription factor pathways. The results of this study provide possible mechanisms whereby HCMV infections might imply suppression of adult T‐cell leukemia. J. Med. Virol. 71:94–104, 2003. © 2003 Wiley‐Liss, Inc.