bluuebunny/crossref_metadata_2025_split huggingface dataset:
Identifying Reservoir Fluids by Wavelet Transform of Well Logs
Authors: Yue Wenzheng , Tao Guo , Liu Zhengwu 
Published: October 2006

Summary
The wavelet-transform (WT) method has been applied to logs to extract reservoir-fluid information. In addition to the time (depth)/frequency analysis generally performed by the wavelet method, we also have performed energy spectral analysis for time/frequency-domain signals by the WT method. We have further developed a new method to identify reservoir fluid by setting up a correlation between the energy spectra and reservoir fluid. We have processed 42 models from an oil field in China using this method and have subsequently applied these rules to interpret reservoir layers. It is found that identifications by use of this method are in very good agreement with the results of well tests.

Introduction
An important log-analysis application is determining reservoir-fluid properties. It is common practice to calculate the water and oil saturations of reservoir formations by use of electrical logs. With the development of well-logging technology, a number of methods have been developed for reservoir-fluid typing with well logs (Hou 2002; Geng et al. 1983; Dahlberg and Ference 1984). A recent report has also described reservoir-fluid typing by the T2 differential spectrum from nuclear-magnetic-resonance (NMR) logs (Coates et al. 2001). However, because of the interference from vugs, fractures, clay content, and mud-filtrate invasion, the reservoir-fluid information contained in well logs is often concealed. The reliability of these log interpretations is thus limited in many cases. Therefore, it is desirable to find a more reliable and consistent way of reservoir-fluid typing with well logs. In this paper, we present a new method using the WT for fluid typing with well logs.
The WT technique was developed with the localization idea from Gabor's short-time Fourier analysis and has been expanded further. Wavelets provide the ability to perform local analysis (i.e., analyze a small portion of a larger signal) (Daubechies 1992).This localized analysis represents the next logical step: a windowing technique with variable-sized regions. Wavelet analysis allows the use of long time intervals, where more-precise low-frequency information is wanted, and shorter intervals, where high-frequency information is needed. Wavelet analysis is capable of revealing aspects of data that other signal-analysis techniques miss: aspects such as trends, breakdown points, discontinuities in higher derivatives, and self-similarity. In well-logging-data processing, wavelet analysis has been used to identify formation boundaries, estimate reservoir parameters, and increase vertical resolution (Lu and Horne 2000; Panda et al. 1996; Jiao et al. 1999; Barchiesi and Gharbi 1999). For data interpretation, however, the identification of hydrocarbon-bearing zones by wavelet analysis is still under investigation. In this study, we have developed a technique of wavelet-energy-spectrum analysis (WESA) to identify reservoir-fluid types. We have applied this technique to field-data interpretation and have achieved very good results.
Condensate Bank Characterization from Well Test Data and Fluid PVT Properties
Authors: Bozorgzadeh Manijeh , Gringarten Alain C. 
Published: October 2006

Summary
Published well-test analyses in gas/condensate reservoirs in which the pressure has dropped below the dewpoint are usually based on a two- or three-region radial composite well-test interpretation model to represent condensate dropout around the wellbore and initial gas in place away from the well. Gas/condensate-specific results from well-test analysis are the mobility and storativity ratios between the regions and the condensate-bank radius. For a given region, however, well-test analysis cannot uncouple the storativity ratio from the region radius, and the storativity ratio must be estimated independently to obtain the correct bank radius. In most cases, the storativity ratio is calculated incorrectly, which explains why condensate bank radii from well-test analysis often differ greatly from those obtained by numerical compositional simulation.
In this study, a new method is introduced to estimate the storativity ratios between the different zones from buildup data when the saturation profile does not change during the buildup. Application of the method is illustrated with the analysis of a transient-pressure test in a gas/condensate field in the North Sea. The analysis uses single-phase pseudo pressures and two- and three-zone radial composite well-test interpretation models to yield the condensate-bank radius. The calculated condensate-bank radius is validated by verifying analytical well-test analyses with compositional simulations that include capillary number and inertia effects.

Introduction and Background
When the bottomhole flowing pressure falls below the dewpoint in a gas/condensate reservoir, retrograde condensation occurs, and a bank of condensate builds up around the producing well. This process creates concentric zones with different liquid saturations around the well (Fevang and Whitson 1996; Kniazeff and Nvaille 1965; Economides et al. 1987). The zone away from the well, where the reservoir pressure is still above the dewpoint, contains the original gas. The condensate bank around the wellbore contains two phases, reservoir gas and liquid condensate, and has a reduced gas mobility, except in the immediate vicinity of the well at high production rates, where the relative permeability to gas is greater than in the bank because of capillary number effects (Danesh et al. 1994; Boom et al. 1995; Henderson et al. 1998; Mott et al. 1999).
RuO4-mediated oxidation of N-benzylated tertiary amines. 3. Behavior of 1,4-dibenzylpiperazine and its oxygenated derivatives
Authors: Petride Horia , Drăghici Constantin , Florea Cristina , Petride Aurica 
Published: October 2006

Abstract
1,4-Dibenzylpiperazine (1),-2-piperazinone (7),-2,6-piperazinedione (9), and 1-benzoyl-4-benzylpiperazine (30) were oxidized by RuO4 (generated in situ) by attack at their endocyclic and exocyclic (i.e., benzylic) aminic N-α-C-H bonds to afford various oxygenated derivatives, including acyclic diformamides, benzaldehyde, and benzoic acid. The reaction outcome was complicated by (i) the hydrolysis of diformamides, occurred during the work-up, and (ii) the reaction of benzaldehyde with the hydrolysis-derived amines giving imidazolidines and/or Schiff bases. Benzoic acid resulted from benzaldehyde only. Compounds 7, 30, and 1-benzylpiperazine, but not 9, were transiently formed during the oxidation of 1. In the same reaction conditions, 1,4-dibenzyl-2,3-(or 2,5)-piperazinedione, 1,4-dibenzyl-2,3,6-piperazinetrione, 4-benzyol-1-benzyl-2-piperazinone, and 1,4-dibenzoylpiperazine were inert. The proposed oxidation mechanism involves the formation of endocyclic and exocyclic iminium cations, as well as of cyclic enamines. The latter intermediates probably result by base-induced deprotonation of the iminium cations, provided an N
+−β-proton is available. In the case of 1, the cations were trapped with NaCN as the corresponding α-aminonitriles. The statistically corrected regioselectivity (endocyclic/exocyclic) of the RuO4-induced oxidation reaction of 1, 7, and 30 was 1.2–1.3.
Spectroscopic methods of studying enzyme action in wool fibre
Authors: Fogorasi Magdalena , Heine Elisabeth 
Published: October 2006

Abstract
Enzymes may be used to develop an environmentally friendly alternative to the conventional polluting technologies in textile finishing. The action of the unlabeled and fluorescent labeled proteolytic enzymes subtilisin and trypsin on wool was examined. Scanning electron micrographs and a diffusion study, based on fluorescence microscopy, localized the enzymatic attack on the fiber. A kinetic study was carried out by monitoring the amino acid content of the treatment liquor.
Enzymatic action is not confined to the fiber surface. To limit attack to the surface and reduce wool damage new treatment methods such as enzyme immobilization onto a solid carrier must be investigated.
Synthesis of Hexagonal‐Phase NaYF4:Yb,Er and NaYF4:Yb,Tm Nanocrystals with Efficient Up‐Conversion Fluorescence
Authors: Yi G. S. , Chow G. M. 
Published: October 2006

AbstractIR‐to‐visible up‐conversion fluorescent nanocrystals of hexagonal‐phase NaYF4:20 %Yb,2 %Er and NaYF4:20 %Yb,2 %Tm have been synthesized by decomposition of multiprecursors of CF3COONa, (CF3COO)3Y, (CF3COO)3Yb, and (CF3COO)3Er/(CF3COO)3Tm in oleylamine at 330 °C. The average particle size is 10.5 ± 0.7 nm (from random measurements of 200 particles from five transmission electron microscopy images) and 11.1 ± 1.3 nm (from dynamic‐light‐scattering measurements). The up‐conversion fluorescence intensity of the hexagonal nanocrystals in this work is much higher than that of other cubic‐phase NaYF4:Yb,Er nanocrystals, including the ones in this work (by a factor of 7.5). Mechanisms for nucleation and growth of the hexagonal‐phase nanoparticles are proposed. These nanocrystals are easily dispersed in organic solvents, producing a transparent colloidal solution. The hydrophobic surfaces of the particles are made hydrophilic using a bipolar surfactant. These nanoparticles and their dispersions in various media have potential applications in optical nanodevices and bioprobes.
Hydrate plug dissociation
Authors: Davies S. R. , Selim M. S. , Sloan E. D. , Bollavaram P. , Peters D. J. 
Published: October 2006

AbstractIt was shown that flowline hydrate plugs dissociate radially not horizontally; this has significant implications for the remediation of a hydrate blockage, a major flow assurance problem. Over a decade of measurements has enabled models to estimate the dissociation time for hydrate plugs in flowlines, using radial heat transfer with two moving boundaries. Three different plug dissociation scenarios were modeled: single‐sided depressurization, two‐sided depressurization, and dissociation by radial electrical heating. The models were able to replicate the experimental observations with no fitted parameters. Structure I hydrate was found to dissociate faster than structure II; this was attributed to the different latent heats between the structures. These results indicate that hydrate dissociation in these systems is limited by heat transfer. © 2006 American Institute of Chemical Engineers AIChE J, 2006
Processing of polypropylene–clay nanocomposites: Single‐screw extrusion with in‐line supercritical carbon dioxide feed versus twin‐screw extrusion
Authors: Treece Mark A. , Oberhauser James P. 
Published: October 2006

AbstractThis work investigates two different melt‐blending strategies for preparing compatibilized polypropylene‐clay nanocomposites, specifically: (1) conventional twin‐screw extrusion, and (2) single‐screw extrusion capable of direct supercritical carbon dioxide (scCO2) feed to the extruder barrel. Proportional amounts (3 : 1) of maleic anhydride functionalized polypropylene compatibilizer and organically modified montmorillonite clay at clay loadings of 1, 3, and 5 wt % are melt‐blended with a polypropylene homopolymer using the two approaches. The basal spacing, degree of exfoliation, and dispersion of organoclay is assessed using X‐ray diffraction, transmission electron microscopy, and rheology. In terms of the latter, both steady shear and small‐amplitude oscillatory shear provide information about the apparent yield stress and solid‐like terminal behavior respectively. Finally, nanoindentation is performed to determine the room temperature modulus of each melt‐blended nanocomposite. The results reveal unequivocally that the high shear of the twin‐screw process is vastly superior to the single‐screw with in‐line scCO2 addition in generating well‐exfoliated, percolated polypropylene‐clay nanocomposites. It is likely that increased contact time between clay and scCO2 is necessary for scCO2 to positively affect exfoliation. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 884–892, 2007
Isothermal decomposition behavior and dynamic mechanical properties of in situ‐reinforcing elastomer composites based on thermoplastic elastomers and thermotropic liquid crystalline polymer
Authors: Saikrasun Sunan , Amornsakchai Taweechai 
Published: October 2006

AbstractIn situ‐reinforcing composites based on two elastomer matrices very different in melt viscosity, styrene–(ethylene butylene)–styrene triblock copolymer (Kraton G1650), and styrene–(ethylene propylene) diblock copolymer (Kraton G1701), and a thermotropic liquid crystalline polymer (TLCP), Rodrun LC3000, were prepared using a twin‐screw extruder. The isothermal decomposition behavior and dynamic mechanical properties of the extruded strands were investigated by means of thermogravimetry (TG) and dynamic mechanical analysis (DMA), respectively. No significant change in the shape of TG curves for the neat matrices and their LC3000‐containing blends was observed under isothermal heating in nitrogen. In air, G1650 and G1701 showed a single weight‐loss stage and rapid decomposition whereas their blends with 30 wt % LC3000 showed different profiles of weight loss depending on isothermal temperatures. The calculated kinetic parameters indicated that the thermal stability of the polymers is much higher in nitrogen than in air and suggested an enhancement of thermal resistance of the elastomer matrices by addition of TLCP. DMA results showed a great enhancement in dynamic moduli for the blend with 10 wt % LC3000 when compared with the neat matrix. The tan δ peaks corresponding to the elastic and hard phases in both matrices mostly shifted to the lower temperature with LC3000 loading. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 917–927, 2007
Preparation and characterization of new photoactive polyamides containing 4‐(4‐dimethylaminophenyl)urazole units
Authors: Mallakpour Shadpour , Rafiee Zahra 
Published: October 2006

Abstract4‐(4‐dimethylaminophenyl)‐1,2,4‐triazolidine‐3,5‐dione (DAPTD) was prepared from 4‐dimethylaminobenzoic acid in five steps. The compound DAPTD was reacted with excess acetyl chloride in N,N‐dimethylacetamide (DMAc) solution and gave 1,2‐bisacetyl‐4‐[4‐(dimethylaminophenyl)]‐1,2,4‐triazolidine‐3,5‐dione as a model compound. Solution polycondensation reactions of monomer with succinyl chloride (SucC), suberoyl chloride (SubC), and sebacoyl chloride (SebC) were performed under conventional solution polymerization techniques in the presence of triethylamine and pyridine as a catalyst in N‐methylpyrrolidone (NMP) and led to the formation of novel aliphatic polyamides. These novel polyamides have inherent viscosities in the range of 0.09–0.21 dL/g in N,N‐dimethylformamide (DMF) at 25°C. Fluorimetric studies of the model compound as well as polymers were performed. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 947–954, 2007
Affinity adsorption of recombinant human interferon‐α on monosize dye‐affinity beads
Authors: Altıntaş Evrim B. , Denizli Adil 
Published: October 2006

AbstractMonosize, nonporous poly(glycidyl methacrylate) [poly(GMA)] beads were prepared by dispersion polymerization. Cibacron Blue F3GA was covalently attached onto the poly(GMA) beads for adsorption of recombinant interferon‐α (rHuIFN‐α). Monosize poly(GMA) beads were characterized by scanning electron microscopy. Dye‐carrying beads (1.73 mmol/g) were used in the adsorption–elution studies. The effect of initial concentration of rHuIFN‐α, pH, ionic strength, and temperature on the adsorption efficiency was studied in a batch system. Nonspecific adsorption of rHuIFN‐α on the beads was 0.78 mg/g. Dye attachment significantly increased the rHuIFN‐α adsorption up to 181.7 mg/g. Equilibrium adsorption of rHuIFN‐α onto the dye‐carrying beads increased with increasing temperature. Negative change in free energy (ΔG0 < 0) indicated that the adsorption was a thermodynamically favorable process. ΔS and ΔH values were 146.1 J/mol K and −37.39 kJ/mol, respectively. Significant amount of the adsorbed rHuIFN‐α (up to 97.2%) was eluted in the elution medium containing 1.0M NaCl in 1 h. To determine the effects of adsorption conditions on possible conformational changes of rHuIFN‐α structure, fluorescence spectrophotometry was employed. We concluded that dye‐affinity beads can be applied for rHuIFN‐α adsorption without causing any significant conformational changes. Repeated adsorption–elution processes showed that these beads are suitable for rHuIFN‐α adsorption. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 975–981, 2007
Functionalization of psyllium with methacrylic acid through grafting and network formation for use of polymers in water treatment
Authors: Kumar Kiran , Verma Monika 
Published: October 2006

AbstractThe psyllium husk, a natural polysaccharide, was modified to develop novel green polymeric materials for use in wastewater treatment technologies. Graft copolymers and three‐dimensional interpenetrating networks (IPNs) of psyllium (Psy) and methacrylic acid (MAAc) were prepared using ammonium persulphate (APS) as initiator. Network formation was carried out using N,N‐methylenebisacrylamide (N,N‐MBAAm) as crosslinker. The hydrogels, thus formed, were characterized using scanning electron microscopy (SEM), FTIR spectroscopy, and thermogravimetric analysis (TGA) to derive the structure–property correlation. Swellability of these hydrogels was analyzed in distilled water and aqueous NaCl solution as a function of time, temperature, pH, and [NaCl]. Flocculation efficiency of graft polymers was analyzed against aqueous kaolin suspension of known concentration as a function of settling time, temperature, amount of polymer, and pH. Novel polymeric materials were also used for the treatment of total hardness in tap water. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 1025–1034, 2007
Aberrant branch of the superior laryngeal artery passing through the thyroid foramen
Authors: Liu Jia‐Lin , Liang Chuan‐Yu , Xiang Tao , Wang Fan , Wang Li‐Hong , Liu Si‐Xi , Yang Hui‐Jun 
Published: October 2006

AbstractThe above article, published online on 27 October 2006 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the journal Editor‐in‐Chief, R. Shane Tubbs, and Wiley Periodicals, Inc. The retraction has been agreed due to overlap with an article published in the Chinese Journal of Otorhinolaryngology Head and Neck Surgery (Liu et al., 2005).
A portrait of Aristotle as an anatomist: Historical article
Authors: Crivellato Enrico , Ribatti Domenico 
Published: October 2006

AbstractAristotle is principally known as a theoretical philosopher and logician but he was also an eminent natural scientist. In particular, he should be considered probably the first anatomist in the modern sense of this term and the originator of anatomy as a special branch of knowledge. Although it seems certain that he did not perform dissections of human adult cadavers, he examined human fetal material and, above all, made systematic analysis of animal bodies. His contribution to comparative anatomy, as well as to human anatomy, was enormous. He founded the anatomical discipline on precise descriptive and scientific ground. He also coined a series of technical terms, which are still in use in the modern nomenclature. His observational skill was astounding. Although many of his physiological concepts turned out to be wrong, still his structural description of organs and body parts was often first‐rank. The present study will chiefly focus on Aristotle's anatomical work and will provide only essential mention of his complex physiological and philosophical doctrine. The main purpose of this article is indeed to offer to today's anatomists a systematic account of the extraordinary achievements of this great pioneer of our discipline. Clin. Anat. 20:477–485, 2007. © 2006 Wiley‐Liss, Inc.
Branches of the petrous and cavernous segments of the internal carotid artery
Authors: Tubbs R. Shane , Hansasuta Ake , Loukas Marios , Louis Jr Robert G. , Shoja Mohammadali M. , Salter E. George , Oakes W. Jerry 
Published: October 2006

AbstractMicrosurgical approaches to the skull base require a thorough knowledge of the microvasculature of this region. Interestingly, most standard texts of anatomy do not mention the branches of the internal carotid artery as it travels through the temporal bone and cavernous sinus. Although small and with often conflicting descriptions, these arterial branches may be of significance when contributing to the vascular supply of such pathological entities as meningiomas and vascular malformations. Furthermore, multiple anastomoses exist between these branches and branches of the external carotid artery, thus providing a potentially important collateral circulation between these two systems and thus retrograde flow needed to maintain the patency of the distal internal carotid artery (ICA) when this vessel is obstructed proximally. We review the literature regarding these branches of the internal carotid artery and their clinical significance. Clin. Anat. 20:596–601, 2007. © 2006 Wiley‐Liss, Inc.
Anatomical investigations and their ethical dilemmas
Authors: Jones D. Gareth 
Published: October 2006

AbstractThe multi‐faceted nature of modern anatomy comes as a surprise to many, especially when confronted by such seemingly different topics as cadavers and human embryo research. However, even these disparate facets of anatomy are linked by common underlying ethical considerations. This article traces historical views of anatomy and places them alongside the more contemporary dimensions of whole‐body plastination, use of human material obtained under unethical circumstances, and human embryo research. These dimensions introduce issues of respect, human dignity, consent, scientific integrity, and societal expectations. Clin. Anat. 20:338–343, 2007. © 2006 Wiley‐Liss, Inc.
Cryoprotection with L‐ and meso‐Trehalose: Stereochemical Implications
Authors: Seo Seung‐Kee , McClintock Michael L. , Wei Alexander 
Published: October 2006

AbstractTwo unnatural stereoisomers of α,α‐trehalose (L‐ and meso‐trehalose) were synthesized and evaluated as cryoprotectants in order to determine the functional consequences of relative or absolute stereochemistry on their physicochemical properties. Adherent yeast cell cultures were frozen in 10 % solutions of D‐, L‐, and meso‐trehalose for periods of 7–28 days, then evaluated by a MTT viability assay. D‐ and L‐trehalose were equally effective in maintaining high rates of cell survival, thus demonstrating the absence of chiral discrimination at the carbohydrate–lipid interface, whereas meso‐trehalose was inferior in cryoprotection efficacy. Differential scanning calorimetry revealed a difference in the glass transition temperatures (Tg) of D‐ and meso‐trehalose of nearly 75 °C. This can be attributed to differences in conformational behavior, as portrayed by torsional energy maps for rotation about the glycosidic bonds of D‐ and meso‐trehalose. We conclude that the biostabilizing properties of α,α‐trehalose depend on relative stereochemical factors, but are independent of absolute stereochemical configuration.
Anforderungen an Werkstoffe und Werkstoffoberflächen bezüglich Reinigbarkeit und Beständigkeit
Authors: Bobe U. , Wildbrett G. 
Published: October 2006

AbstractFür die Produktion von Lebensmitteln und Pharmazeutika spielt die Auswahl des richtigen Werkstoffes für den Anlagenbau eine wichtige Rolle. Die Frage, wie die produktberührende Oberfläche den Produktionsablauf beeinflusst, ist von zentraler Bedeutung. Dabei wird von den Oberflächen häufig gefordert, dass sie durch ihre Reinigbarkeit und Korrosionsbeständigkeit eine nachhaltig sichere, störungsfreie und kostengünstigere Produktion gewährleisten. Dieser Beitrag zeigt, wie der aktuelle Stand der Forschung hinsichtlich der Auswirkungen der Werkstoffoberflächen auf die Reinigbarkeit ist. Des Weiteren werden Ursachen für mögliche Korrosionsschäden an nichtrostenden Edelstählen einschließlich der Möglichkeiten zur Schadensverhütung sowie der Einsatzbereich von EPDM als elastomeres Dichtungsmaterial behandelt.