bluuebunny/crossref_metadata_2025_split huggingface dataset:
Data Quality of PAH Determinations in Environmental Monitoring
Authors: Borsella Elisabetta , di Filippo Patrizia , Riccardi Carmela , Spicaglia Sergio , Cecinato Angelo 
Published: September 2004

AbstractThe sources of uncertainty affecting measurements of pollutants include sample collection, handling and stocking, and analytical procedure. With regard to chemical analysis, MS detection offers a series of advantages for resolving complex mixtures and identify and quantify analytes present at very small extents. Nevertheless, it presents some problems of reproducibility, which can affect the quality of quantitative data. PAH represent keycompounds among atmospheric pollutants and are usually evaluated by means of dedicated methods comprising MS detection. Based upon the above considerations, an analytical method has been standardized, suitable for determining PAH in atmospheric aerosols and diesel particulate exhausts. To test the procedure, both diesel particulate and urban aerosol NIST reference materials (SRM—2975 and SRM—1649A, respectively) have been processed and the results have been compared with certified and/or literature data. The results obtained are shortly discussed.
Determination of Phenolic Acids in Olive Oil by Capillary Electrophoresis
Authors: Buiarelli Francesca , di Berardino Sonia , Coccioli Franco , Jasionowska Renata , Russo Mario Vincenzo 
Published: September 2004

AbstractA CZE method for the separation and quantitation of phenolic acids (cinnamic, syringic, p—coumaric, vanillic, caffeic, 3, 4—dihydroxyphenylacetic, protocatechuic), extracted from extra virgin olive oil, was developed. The sample preparation involved the LLE and SPE extraction methods. CE separation was performed in a fused silica capillary of I. D. = 50μm using as a BGE 40 mM borate buffer at pH = 9.2. The separation voltage was 18kV with corresponding current of 2728 μA. Detection was accomplished with UV—detector at λ = 200nm. The proposed method was fully validated. A good repeatability of migration time (RSD% ranged from 0.81 to 1.63) and of corrected peak area ( RSD% from 2.89 to 5.77) was obtained. The linearity of detector response in the range from 5 to 50 ppm was checked, obtaining the correlation coefficient R2 values in the range: 0.9919—0.9997. Some phenolic acids in real oil samples were detected and quantified with the proposed method.
Remote Sensing Measurements for Evaluation of Air Quality in an Urban Area
Authors: Avino Pasquale , Brocco Domenico , Lepore Luca , Russo Mario V. , Ventrone Ida 
Published: September 2004

AbstractThe Differential Optical Absorption Spectrometry (DOAS) is a remotesensing technique finding greater consents in these last years. The analytical principle of the DOAS system is based on the light absorption in the near—UV and Vis regions of those pollutants with fine vibrational structures such as SO2, NO2, O3, nitrous acid, formaldehyde, benzene, toluene, etc. The relationship among the adsorbed light intensity and the xompound concentrations is ruled by the Lambert—Beer's law. The DOAS analysis allows to study and to interpretate the complex mechanisms of the formation and transformation of the pollutants and particularly of those of secondary origin. In this paper we have reported and discussed the behaviors of NO2, O3, HNO2, formaldehyde, benzene and toluene measured by this system during the 2000—2003 period in the Rome area (an area highly influenced by anthropogenic sources) and in Pietracupa (Molise) area (considered as remote site). The results show how the DOAS system highlight very well the secondary pollution evolution; this, described by the profiles of NO2 and O3 being at the same time products and precursors of the photochemical smog, is not influenced by the emission flow intensity and consequently assumes homogeneous values in the whole urban area.
Paper Chromatographic and Paper Elettrophoretic Study of the Solution Chemistry of Tc—99m—Methylendiphosphonate and of Tc—99m—Dimercaptosuccinate for Improving the Tumouraffinity of Tc—99—m During Scintigraphic Imaging of Cancer
Authors: Shukla Shyama Kant , Atzei Giampiero , Sedda Antioco Franco , Rossi Gabriele , Cipriani Cesidio 
Published: September 2004

AbstractIn order to find the conditions under which Tc—99m—methylenediphosphonate (Tc—99m—MDP) and Tc—99m (V)�dimercaptosuccinate (Tc—99m (V)�DMSA) may become tumourseeking agents, leaving healthy organs free from the radionuclide uptake, the solution chemistry of these radiopharmaceuticals was studied by paper chromatography and paper electrophoresis in distilled water, in physiological saline, in NAHCO3, and ascorbic acid solutions. Both radiopharmaceuticals are anionic in the radiopharmaceutical solution but get easily hydrolysed to form cationic Tc—99m species which concentrates in healthy bone and in some bone metastases. Tc—99m (V)�DMSA being more stable remains long in the blood pool giving undesirable presence of the radionuclide in lung, heart and kidneys, in addition to its reduced uptake in bone metastases and in some primaries. We are trying to eliminate these drawbacks of healthy organ uptake of Tc—99m (V)�DMSA not only to get a clean scintigraphic image of the tumour with this radiopharmaceutical but to extend its formulation, thus obtained, to prepare radiopharmaceutical with Re—188, which is the higher homologue of Tc—99m, for systemic therapy of cancer. Essentially similar solution chemistry of both radiopharmaceuticals suggests that like Tc—99m—MDP, technetium—99m—dimercaptosuccinate is also a complex of tetravalent Tc—99m and not of pentavalent Tc—99m as so far supposed to be.
Characterization of dynamics of gas–liquid flows in rectangular bubble columns
Authors: Buwa Vivek V. , Ranade Vivek V. 
Published: September 2004

AbstractGas–liquid flow in bubble columns is inherently unsteady. The unsteady fluid dynamics influences mixing and other transport processes occurring in bubble column reactors. In this work, we have characterized dynamics of gas–liquid flows in rectangular bubble columns using wall pressure and voidage fluctuations. The low‐frequency oscillations caused by meandering bubble plume were characterized using the plume oscillation period. Experiments were carried out to study the influence of superficial gas velocity, sparger configuration, and liquid height‐to‐width (H/W) ratio on the low‐frequency oscillations. The dimensional analysis based on analogy between buoyancy‐driven thermal and bubbly flows was carried out to relate low‐frequency oscillations to various design and operating parameters. This analysis was able to correlate present as well as previously published experimental data. We have further demonstrated the importance of establishing such a quantitative relationship for validation of computational fluid dynamics (CFD)–based models by carrying out CFD simulations of gas–liquid flow in rectangular bubble columns. The importance of bubble‐scale information obtained using conductivity probes in validating Eulerian–Lagrangian models is also demonstrated. © 2004 American Institute of Chemical Engineers AIChE J, 50: 2394–2407, 2004
A comparative adsorption study of copper on various industrial solid wastes
Authors: Agrawal Archana , Sahu K. K. , Pandey B. D. 
Published: September 2004

AbstractThe adsorption behavior of Cu on three solid waste materials—sea nodule residue (SNR), fly ash (FA), and red mud (RM)—was investigated. The effects of various parameters, such as pH of the feed solution, contact time, temperature, adsorbate and adsorbent concentration, and particle size of the adsorbent, were studied for optimization of the process parameters. Adsorption of copper increased with increasing time, temperature, pH, and adsorbate concentration, and decreased with increasing initial copper concentration. The equilibrium data fit well with the Langmuir and Freundlich isotherms in the case of SNR, but not on RM and FA, because there was no appreciable effect of temperature on the metal removal on these two adsorbents. The adsorption of copper on SNR followed first‐order kinetics involving the surface complex formation mechanism on the charged surface. Under the optimized conditions the adsorption capacity for copper was found to be 19.65 mg/g of SNR, 1.98 mg/g of FA, and 2.28 mg/g of RM. Thus the adsorption capacity of SNR was found to be more than that of activated carbon, thus making it suitable for the treatment of industrial effluents to reduce the level of copper within the permissible limits for its land disposal (3 mg/L) according to ISI guidelines. © 2004 American Institute of Chemical Engineers AIChE J 50: 2430–2438, 2004
NOx storage and reduction with propylene on Pt/BaO/alumina
Authors: Muncrief Rachel L. , Kabin Karen S. , Harold Michael P. 
Published: September 2004

AbstractAn experimental study was carried out of periodically operated NOx (NO + NO2) storage and reduction on a model Pt/BaO/Al2O3 catalyst powder. The effect of the reductant (propylene) injection policy on time‐averaged NOx conversion was evaluated in terms of feed composition and temperature, reductant pulse duration, and overall cycle time. Conditions giving time‐averaged NOx conversions exceeding 90% were identified. The reductant‐to‐oxidant ratio during the injection and the total cycle time are both found to be critical factors to achieve high conversion. The time‐averaged conversion is bounded above and below by the steady‐state conversions obtained with feeds having the same compositions as that during the rich and lean part of the cycle, respectively. For a fixed supply of propylene, short pulses of high concentration are much more effective than longer pulses of reduced concentration. The NOx conversion achieves a maximum value at an intermediate overall cycle time when the propylene pulse of fixed duty fraction is net reducing. High conversions are sustained over a wide temperature window (200–400°C). A simple storage–reduction cycle is proposed that elucidates the main findings in the study. The key factor for high NOx conversion is the temporal production of oxygen‐deficient conditions coupled with high catalyst temperatures, both resulting from the intermittent catalytic oxidation of propylene. © 2004 American Institute of Chemical Engineers AIChE J, 50: 2526–2540, 2004
Improved PCA process for the production of nano‐ and microparticles of polymers
Authors: Pérez Y. , Wubbolts F. E. , Witkamp G. J. , Jansens P. J. , de Loos Th.W. 
Published: September 2004

AbstractThe system dextran‐DMSO‐CO2 has been chosen as a model system to study the fundamentals of the precipitation of biodegradable polymers, using the precipitation with a compressed antisolvent (PCA) process. At conditions of completely miscibility between the organic solvent (DMSO) and CO2, it is proposed that the formation of droplets in the system is not the consequence of atomization of the DMSO solution, but rather the result of the occurrence of a liquid‐liquid phase split when the DMSO‐solution and CO2 are intimately mixed. Penetration of CO2 into the droplets and stripping of DMSO induces the solidification of these droplets. A new device was designed to separate the three steps involved in the process: mixing of CO2 and solution, liquid‐ liquid phase split, and stripping of the solvent. This new device eliminates agglomeration of particles, and yields reproducible results. The particle size can be easily manipulated over a size range from several nanometers to tenths of microns by changes in the operating conditions. The influence of these operating conditions (pressure, temperature, polymer concentration, and solution/CO2 composition ratio) on particle morphology has been studied. © 2004 American Institute of Chemical Engineers AIChE J, 50: 2408–2417, 2004
Asphaltene precipitation in crude oils: Theory and experiments
Authors: Buenrostro‐Gonzalez Eduardo , Lira‐Galeana Carlos , Gil‐Villegas Alejandro , Wu Jianzhong 
Published: September 2004

AbstractThe precipitation of asphaltenes in two Mexican crude oils was measured using a combination of high‐pressure isothermal expansion and atmospheric titration with n‐alkanes. Experiments were carried out from the live‐ and tank‐oil type of samples of the same crude oils. For the oils investigated, compositional data, precipitation phase diagrams, and bubble point pressures are reported. A theoretical study for these systems was performed using the statistical association fluid theory for potentials of variable range (SAFT‐VR) equation of state (EOS) in the framework of the McMillan–Mayer theory. By matching a single titration curve or two precipitation onset points with this EOS, a good prediction of asphaltene precipitation over wide temperature, pressure, and composition intervals is obtained. © 2004 American Institute of Chemical Engineers AIChE J, 50: 2552–2570, 2004
A systemic approach for pellet reactor modeling: Application to water treatment
Authors: Montastruc L. , Azzaro‐Pantel C. , Pibouleau L. , Domenech S. 
Published: September 2004

AbstractThe development is reported of a model for a fluidized‐bed process for phosphate precipitation and removal from wastewater. The general framework of this study involves a two‐step procedure. The first modeling level was previously presented elsewhere and leads to the development of a thermodynamic model for the computation of phosphate conversion for the Ca–PO4–H2O system. The second step of the modeling procedure is the core of this report and computes the reactor efficiency from the identification of the so‐called pellet reactor model as a reactor network involving a combination of elementary systems representing basic ideal flow patterns (perfect mixed flow, plug flow, and so on). For solving the involved mixed‐integer quadratic programming (MIQP) problem, a hybrid procedure based on simulated annealing (SA) and quadratic programming (QP) is implemented. The SA generates reactor network structures deduced from a superstructure and for each one, a QP is carried out. The goal is to find not only the most appropriate model, but also the simplest one (in terms of the smallest possible number of elementary units). Thus the objective function is augmented with an outer penalty quadratic function representing the number of elementary units. The methodology was first validated on an example previously treated with a classical MINLP method involving a limited number of variables. The main interest of the approach proposed here is that it can handle large‐size problems with a limited exploration of the search space and can be consequently extended to combinatorial problems. A comparison with experimental results obtained in the pilot unit designed for this study shows the efficiency of the systemic approach. © 2004 American Institute of Chemical Engineers AIChE J, 50: 2514–2525, 2004
Self‐organization kinetics of mesoporous nanostructured particles
Authors: Gradoń Leon , Janeczko Stanislaw , Abdullah Mikrajuddin , Iskandar Ferry , Okuyama Kikuo 
Published: September 2004

AbstractSpray drying a mixture of silica and polystyrene latex (PSL) colloids above the decomposition temperature of PSL results in the formation of porous silica particles. By appropriate selection of the experimental conditions, such as the use of a tubular temperature, the weight fraction of colloids, and the flow rate of carrier gas, the resulting silica particles contain organized pores with a hexagonal close‐packing arrangement. The process by which organized mesoporous silica particles are formed by the spray‐drying method was examined using elementary laws of topology. Although a direct test using experimental data was not performed, at least qualitatively, the existence of a “stationary state” at which organized mesoporous particles can be produced with hexagonal close packing could be defined. Deviation from this stationary state results in the formation of unorganized pores as well as a deformed particle shape, rather than spherical ones. © 2004 American Institute of Chemical Engineers AIChE J, 50: 2583–2593, 2004
A new neocentromere locus on chromosome 13 resulting in mosaic tetrasomy for distal 13q and an asymmetric phenotype
Authors: Barwell Julian , Mazzaschi Roberto , Bint Sue , Ogilvie Caroline Mackie , Elmslie Frances 
Published: September 2004

AbstractAn 8‐year‐old girl was referred to the Genetics Centre with mild developmental delay, mild dysmorphic features, and a head circumference on the 98th centile. She was noted to have large irregular ear lobes, torticollis, and mild hemihypertrophy. Karyotype analysis of cultured peripheral lymphocytes and skin fibroblasts revealed the presence of a symmetrical supernumerary marker chromosome in 13% of cells from both tissue types. Further analysis showed that this marker chromosome originated from the distal region of chromosome 13 and contained no centromeric α‐satellite DNA. The marker chromosome was not found in blood from the parents. This case represents a novel symmetrical structure with a previously unreported neocentromere locus, leading to an unusual phenotype. Similar cases of individuals with a chromosome 13 with a neocentromere have been reported. They are reviewed and compared with the current case. The importance of scanning metaphases for abnormalities in individuals presenting with asymmetry is emphasized. © 2004 Wiley‐Liss, Inc.
Eyelid myxoma in Carney complex without PRKAR1A allelic loss
Authors: Tsilou Ekaterini T. , Chan Chi‐Chao , Sandrini Fabiano , Rubin Benjamin I. , Shen De Fen , Carney J. Aidan , Kaiser‐Kupfer Muriel , Stratakis Constantine A. 
Published: September 2004

AbstractEyelid nodules were investigated in a patient with Carney complex who was heterozygous for the most commonly known PRKAR1A‐inactivating mutation, c.578delTG. Immunohistochemical studies confirmed the diagnosis of myxoma. Loss of heterozygosity was not present, suggesting that haploinsufficiency alone was responsible for tumorigenesis of this eyelid lesion. Published 2004 Wiley‐Liss, Inc.
The natural history, including orofacial features of three patients with Ehlers–Danlos syndrome, dermatosparaxis type (EDS type VIIC)
Authors: Malfait Fransiska , De Coster Peter , Hausser Ingrid , van Essen Anthonie J. , Franck Peter , Colige Alain , Nusgens Betty , Martens Luc , De Paepe Anne 
Published: September 2004

AbstractEhlers–Danlos syndrome (EDS) dermatosparaxis type (type VIIC) and the related disease of cattle dermatosparaxis, are recessively inherited connective tissue disorders, caused by a deficient activity of procollagen I N‐proteinase, the enzyme that excises the N‐terminal propeptide in procollagen type I, type II, and type III. Although well documented in cattle, to date only seven human cases have been recorded, most of them aged under 2 years. We document the natural history of three patients with EDS dermatosparaxis type, two of whom have been reported before the age of 2 years, and one new patient. The phenotype of the patients, and especially the facial resemblance, is striking, making this a clinically recognizable condition. The most consistent anomalies during the first years of life are premature rupture of the membranes, extreme skin fragility and easy bruising, large fontanels, blue sclerae, puffy eyelids, micrognathia, umbilical hernia, and short fingers. Joint hypermobility becomes more important with age. The children are at risk for rupture of internal organs due to soft tissue fragility, as is illustrated by different internal events in two of the three patients described here. Orofacial features include micrognathia, a frontal open bite, and gingival hyperplasia with varying degrees of hyperkeratosis. The deciduous dentition shows abnormal morphology of the molars, obliteration of the tooth pulp, and severe enamel attrition. The permanent dentition shows agenesis and microdontia of several teeth. Tooth discoloration, dysplastic roots, and tooth pulp obliteration are present in a restricted number of permanent teeth. © 2004 Wiley‐Liss, Inc.
Detection of an interstitial deletion of 2q21‐22 by high resolution comparative genomic hybridization in a child with multiple congenital anomalies and an apparent balanced translocation
Authors: Shanske A.L. , Edelmann L. , Kardon N.B. , Gosset P. , Levy B. 
Published: September 2004

AbstractVarious molecular cytogenetic techniques are currently available to accurately characterize chromosome rearrangements in patients with multiple congenital anomalies. Among these is comparative genomic hybridization (CGH) whose main advantage is the ability to perform a whole genome scan without prior knowledge of the underlying chromosome abnormality. It has been used mostly in the area of cancer cytogenetics, but its role in clinical genetics is now expanding to even include preimplantation genetic diagnosis. We have used this method to reveal an interstitial deletion in a patient with multiple anomalies, who had for years been thought to have a de novo balanced translocation involving chromosomes 1 and 2. A review of published reports suggests that there is significant phenotypic and genetic heterogeneity in the small group of patients including our own with interstitial deletions of 2q21‐q22. © 2004 Wiley‐Liss, Inc.
Classical West “syndrome” phenotype with a subtelomeric 4p trisomy
Authors: Gérard‐Blanluet Marion , Romana S. , Munier C. , Le Lorc'h M. , Kanafani S. , Sinico M. , Touboul C. , Levaillant J.M. , Haddad B. , Lopez N. , Lelong F. , de Villemeur T. Billette , Verloes A. , Borghi E. 
Published: September 2004

AbstractWe report a girl with mild mental retardation with onset of infantile spasms at age of 9 months. Treatment with a short course of adrenocorticotropic hormone (ACTH) was successful. Initially, a diagnosis of idiopathic West syndrome, with good neurological outcome and disappearance of epilepsy after treatment, was made. Conventional karyotype was normal. Reinvestigations were done at age 8 years, because of a new pregnancy. Karyotyping of both parents was done because of mild dysmorphic features in the proband, and to eliminate other causes than early age epilepsy as the etiology of her mental retardation. Parental karyotypes showed a balanced paternal translocation (4p;17q) resulting in partial 4p trisomy, without significant 17q monosomy in the proband. Chromosomal abnormalities usually lead to a severe West syndrome with poor prognosis of neurological outcome (persistent severe epilepsy, mental retardation, and behavioral disturbances). The presence of an undetected cytogenetic anomaly in our proband with transient hypsarythmia is unusual and led us to propose systematic telomeric screening in apparently “idiopathic” West syndrome patients with mild mental retardation and subtle dysmorphic features. © 2004 Wiley‐Liss, Inc.