bluuebunny/crossref_metadata_2025_split huggingface dataset:
High-Resolution 3D VSP Processing - An Example from the Middle East
Authors: Chavarria J. Andres , Paulsson Bjorn , Goertz Alexander , Karrenbach Martin , Mueller Klaus , Marmash Samer , Al-Baloushi Mariam , Soroka William 
Published: November 2008

Abstract
The 3D VSP method is being increasingly employed as a tool to produce high-resolution images for detailed reservoir characterization and to address reservoir challenges. These challenges include thin layer reservoirs, thief zones and stratigraphic features that affect recovery. The main challenges in processing VSP datasets are twofold: First to ensure that the high frequency and better vector fidelity is being used and carried through to the final image. This requires special care and appropriately adapted processing techniques to the smaller scale and high frequency contained in the VSP data. Second, is dealing with the unique geometry of a 3D VSP, which has laterally varying fold coverage and aperture that has to be accounted for in order to minimize any footprint on the final image.
In this project VSP processing advances have been made using data from the largest 3D VSP recorded to date, which was acquired in an Abu Dhabi oil field. Different types of static corrections were tested and optimized to recover the high frequencies required for optimum event delineation. A combination of static corrections that takes full advantage of the 3D VSP geometry and includes surface seismic data results that helped achieve optimal coherency of events. A careful analysis of the irregular fold geometry resulted in good target imaging using a detailed illumination analysis. Such an analysis aids in the correct treatment of the high resolution events and helps to interpret their character along the area illuminated. This analysis provides critical information about the velocity model and the corresponding kinematics. The ability of VSP's to recover high frequencies is demonstrated in this processing flow, by showing the difference in resolution between new high resolution surface seismic and the final 3D VSP image.
Green’s function for an electron model with a plane wave
Authors: Ould Lahoucine Hassen , Chetouani Lyazid 
Published: November 2008

Abstract
The Green function for a Dirac particle subject to a plane wave field is constructed according to the path integral approach and the Barut’s electron model. Then it is exactly determined after having fixed a matrix U chosen so that the equations of motion are those of a free particle, and by using the properties of the plane wave and also with some shifts.
Development of a Medical-text Parsing Algorithm Based on Character Adjacent Probability Distribution for Japanese Radiology Reports
Authors: Terae S. , Uesugi M. , Ogasawara K. , Sakurai T. , Nishimoto N. 
Published: November 2008

Summary

Objectives:
The objectives of this study were to investigate the transitional probability distribution of medical term boundaries between characters and to develop a parsing algorithm specifically for medical texts.

Methods:
Medical terms in Japanese computed tomography (CT) reports were identified using the ChaSen morphological analysis system. MeSH-based medical terms (51,385 entries), obtained from the metathesaurus in the Unified Medical Language System (UMLS, 2005AA), were added as a medical dictionary for ChaSen. A radiographer corrected the set of results containing 300 parsed CT reports. In addition, two radiologists checked the medical term parsing of 200 CT sentences.

Results:
We obtained modified inter-annotator agreement scores for the text corrected by the radiologists. We retrieved the transitional probability as the conditional probability of a uni-gram, bi-gram, and tri-gram. The highest transitional probability P(Ci | Ci - 2*Ci - 1) was 1.00. For an example of anatomical location, the term “pulmonary hilum” was parsed as a tri-gram.

Conclusions:
Retrieval of transitional probability will improve the accuracy of parsing compound medical terms.
Modification of polysulfone membranes via surface‐initiated atom transfer radical polymerization and their antifouling properties
Authors: Li Liang , Yan Guoping , Wu Jiangyu 
Published: November 2008

AbstractSurface‐initiated atom transfer radical polymerization (ATRP) was used to tailor the functionality of polysulfone (PSF) membranes. A simple one‐step method for the chloromethylation of PSF under mild conditions was used to introduce surface benzyl chloride groups as active ATRP initiators. Covalently tethered hydrophilic polymer brushes of poly(ethylene glycol)monomethacrylate and 2‐hydroxyethyl methacrylate and their block copolymer brushes were prepared via surface‐initiated ATRP from the chloromethylated PSF surfaces. A kinetic study revealed that the chain growth from the membranes was consistent with a controlled process. X‐ray photoelectron spectroscopy was used to characterize the surface‐modified membrane after each modification stage. Protein adsorption experiments revealed substantial antifouling properties of the grafted PSF membranes in comparison with the those of the pristine PSF surface. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Copolymerization of ethylene and cyclopentene with the Phillips CrOx/SiO2 catalyst in the presence of an aluminum alkyl cocatalyst
Authors: Xia Wei , Tonosaki Kiwamu , Taniike Toshiaki , Terano Minoru , Fujitani Tadahiro , Liu Boping 
Published: November 2008

AbstractThe Phillips CrOx/SiO2 catalyst is an important industrial catalyst for ethylene polymerization. However, understanding of the state of active sites and chain propagation mechanisms concerning the Phillips catalyst is still waiting for conclusive evidence. In this work, the Phillips CrOx/SiO2 catalyst, having been calcined, was used for investigating the copolymerization of ethylene and cyclopentene in the presence of triethylaluminum as a cocatalyst for the first time. The microstructures of the polymers were investigated with 13C‐NMR and gel permeation chromatography methods. Because of the absence of internal double bond (CC) in the copolymer main chain, the ring‐opening metathesis polymerization of cyclopentene was excluded during the copolymerization stage of ethylene and cyclopentene. Also, the 1,2‐insertion and 1,3‐insertion of cyclopentene into the polyethylene main chain were confirmed. This evidence strongly implies that CrC species may not be the active sites for chain propagation; instead, the CrC active site model under the Cossee–Arlman chain propagation mechanism may be responsible for the chain propagation during the normal polymerization period. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Effects of pH and temperature on the sorption of sodium dodecyl sulfate by cellulose acetate/polyaniline blend membranes
Authors: Pereira R. F. P. , Cerqueira D. A. , Valente A. J. M. , Polishchuk A. Y. , Burrows H. D. , Lobo V. M. M. 
Published: November 2008

AbstractCellulose acetate/polyaniline (PANi) blends show a selective response to the presence of sodium dodecyl sulfate (SDS). Such detection can be monitored by visible absorption spectroscopy. In this article, we show how this is dependent on the pH and temperature. At pH 2, the redshift of the maximum absorbance wavelength of blend films is essentially dependent on hydrochloric acid; however, at pH 3, this effect clearly decreases, and at pH values between 4 and 6, the alteration of the blend color depends only on SDS. The selective detection of SDS is faster with a higher percentage of PANi in the blend. At 25°C, the mechanism of sorption is essentially Fickian for short times, but this changes at higher temperatures, and at temperatures of 40°C and higher, the sorption kinetics show an initial time lag in which no visible response from the blend to SDS is detected. The response rate of blends to SDS detection increases with the temperature and PANi content. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Facile synthesis of functional silica/polymer composite materials and hydrophilic hollow polymer microspheres
Authors: Liu Guangyu , Zhang Han , Yang Xinlin , Wang Yongmei 
Published: November 2008

AbstractMonodisperse functional silica/polymer core‐shell composite materials with silica as core and hydrophilic polymer with various functional groups, such as amide, carboxylic acid, hydroxyl, and pyridyl group, as shell were facilely prepared by a two‐stage reaction, in which the silica core with diameter of 179 nm was synthesized in the first‐stage reaction according to the Stöber method. The functional polymer shell was then encapsulated onto the silica core by distillation–precipitation copolymerization of N,N′‐methylenebisacrylamide (MBAAm) as crosslinker and hydrophilic comonomers with different functional groups, including N‐isopropylacrylamide, methacrylic acid, 2‐hydroxyethyl methacrylate, and 4‐vinylpyridine, in neat acetonitrile with 2,2′‐azobisisobutyronitrile as initiator. The encapsulation of the functional polymer shell onto the silica core particles was driven by the hydrogen‐bonding interaction between the hydroxyl group on the surface of silica core and the amide unit of MBAAm crosslinker as well as the functional groups of the comonomers during the distillation–precipitation polymerization without modification of the silica surface in absence of any stabilizer or surfactant. The shell thickness of the composite can be controlled by MBAAm fraction in the monomer feed during the polymerization. Hydrophilic hollow polymer microspheres with various functional groups, including amide, carboxylic acid, hydroxyl, and pyridyl, were further developed after selective removal of silica core with hydrofluoric acid. The functional core‐shell silica/polymer composites and the corresponding functional hollow microspheres were characterized with transmission electron microscopy, Fourier transform infrared spectra, and dynamic light scattering. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Modification of the molar anionic charge density of acetone–formaldehyde–sulfite dispersant to improve adsorption behavior and effectiveness in the presence of CaAMPS®‐co‐NNDMA cement fluid loss polymer
Authors: Plank Johann , Dugonjić‐Bilić Fatima , Lummer Nils Recalde 
Published: November 2008

AbstractSulfonated aldol polycondensates were synthesized from acetone, formaldehyde, and different amounts of sodium sulfite, resulting in polymers with varying degrees of sulfonation (DS). The anionic charge amount of these macromolecules measured by polyelectrolyte titration decreased with lower DS. The effectiveness of the acetone–formaldehyde–sulfite (AFS) polycondensates as cement dispersant was found to depend on the amount of polymer adsorbed on cement. AFS adsorption decreases with lower DS. Interaction and compatibility between AFS and CaAMPS®‐co‐NNDMA fluid loss additive was studied by formulating binary additive systems composed of one of the modified AFS polymers and CaAMPS‐co‐NNDMA. At high DS, AFS adsorbs strongly and prevents CaAMPS‐co‐NNDMA from adsorbing in sufficient amounts on the cement surface. The result is poor fluid loss control of the cement slurry. AFS polymers with lower DS, however, allow simultaneous adsorption of both polymers in sufficient quantities to provide good fluid loss control and low rheology at the same time. Thus, effectiveness of both additives was retained. Obviously, effectiveness of such multi‐admixture systems depends on the adjustment of the adsorption behavior of the individual components relative to each other. Molar anionic charge density of the polymers was found to be a major parameter influencing their relative adsorption behavior. The AFS polymer with DS = 0.2 possesses a molar anionic charge density comparable to CaAMPS‐co‐NNDMA. Thus, when admixtures with similar molar anionic charge densities are used, the performance of one component is not negatively influenced by the other. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Polymeric Salphen‐phthalocyanine dinuclear metal complexes for activation of molecular oxygen
Authors: Wang Rong‐Min , Hao Er‐Xia , Shen Guo‐Rui , He Yu‐Feng , Lei Zi‐Qiang 
Published: November 2008

AbstractThe polymeric Salphen Schiff base‐phthalocyanine Co‐Cu dinuclear metal complex (PSalphenCo‐PcCu) was designed and synthesized through interfacial condensation polymerization. The new sheet polymeric dinuclear metal complex has been characterized by IR spectra, UV‐visible spectra, scanning electron microscopy with energy dispersive X‐ray analysis and thermogravimetry analysis. Its catalytic activity for activation of molecular oxygen was investigated by using cumene as substrate without any additive in mild condition. The aerobic oxidation of cumene catalyzed by PSalphenCo‐PcCu proved to be a simple and efficient method for obtaining cumene hydroperoxide in a high selectivity. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
A new approach for detecting scientific specialties from raw cocitation networks
Authors: Wallace Matthew L. , Gingras Yves , Duhon Russell 
Published: November 2008

AbstractWe use a technique recently developed by V. Blondel, J.‐L. Guillaume, R. Lambiotte, and E. Lefebvre (2008) to detect scientific specialties from author cocitation networks. This algorithm has distinct advantages over most previous methods used to obtain cocitation “clusters” since it avoids the use of similarity measures, relies entirely on the topology of the weighted network, and can be applied to relatively large networks. Most importantly, it requires no subjective interpretation of the cocitation data or of the communities found. Using two examples, we show that the resulting specialties are the smallest coherent “groups” of researchers (within a hierarchy of cluster sizes) and can thus be identified unambiguously. Furthermore, we confirm that these communities are indeed representative of what we know about the structure of a given scientific discipline and that as specialties, they can be accurately characterized by a few keywords (from the publication titles). We argue that this robust and efficient algorithm is particularly well‐suited to cocitation networks and that the results generated can be of great use to researchers studying various facets of the structure and evolution of science.
Net energy: still a (mostly) irrelevant, misleading and dangerous metric
Authors: Dale Bruce E. 
Published: November 2008

AbstractClassical net energy analysis does not define “net energy” as Dr. Pimentel has defined it. Classical net energy analysis has limited value. Dr. Pimentel's use of net energy to attack biofuels is irrelevant, misleading and even dangerous in a world struggling to find alternatives to petroleum. © 2008 Society of Chemical Industry and John Wiley & Sons, Ltd
Response to Dr. Poldy's questions in this issue
Authors: Dale Bruce E. 
Published: November 2008

Abstract Some have written to this journal to take issue with my characterization of net energy as an irrelevant and misleading metric for fuel performance. We welcome open discussion of controversial issues related to biofuels in this journal and so have invited Dr. Franz Poldy (CSIRO Sustainable Ecosystems, Australia) to write a defense of net energy and critique of my earlier article. Since I am the Editor in Chief, I get to have the last word, and have briefly responded to Dr. Poldy's article. It is apparent that Dr. Poldy uses a different definition of net energy than does Dr. Pimentel. We invite the readers to consider the arguments and make up their own minds.© 2008 Society of Chemical Industry and John Wiley & Sons, Ltd
Mechanism of cellulase reaction on pure cellulosic substrates
Authors: Gupta Rajesh , Lee Y.Y. 
Published: November 2008

AbstractCellulase reaction mechanism was investigated with the use of following pure cellulosic substrates: Microcrystalline cellulose (Avicel), α‐cellulose (Sigma), filter paper, cotton, and non‐crystalline cellulose (NCC). NCC is amorphous cellulose prepared in our laboratory by treatment with concentrated sulfuric acid. When hydrolyzed with cellulase, NCC produces significant amount of cello‐oligosaccharides (COS) as reaction intermediates along with glucose and cellobiose. The COS produced by cellulase were categorized into two different moieties based upon their degree of polymerization (DP): low DP (less than 7) COS (LD‐COS) and high DP COS (HD‐COS). Endo‐glucanase (Endo‐G) reacts rapidly on the NCC reducing its DP to 30–60, after which the Endo‐G reaction with NCC ceases. HD‐COS is produced from NCC by the action of Endo‐G, whereas LD‐COS is produced by exo‐glucanase (Exo‐G). β‐Glucosidase (β‐G) hydrolyzes LD‐COS to produce cellobiose, but it does not hydrolyze HD‐COS. DP of NCC affects the action of Exo‐G in such a way that the overall yield is high for high DP NCC. This is in line with previous findings that substrate‐recognition by Exo‐G requires binding on β‐glucan chain with DP of 10 for the hydrolysis to take place. The individual cellulose chain residues within solid having DP less than 10 therefore remain unreacted. The percentage of the unreacted portion would be lower for high DP NCC, which results high overall conversion. The surface area and the number of reactive sites on the substrate facilitate adsorption of enzyme therefore the initial rate of the hydrolysis. The overall extent of conversion of cellulose, however, is controlled primarily by its inherent characteristics such as DP and crystallinity. Biotechnol. Bioeng. 2009;102: 1570–1581. © 2008 Wiley Periodicals, Inc.
Small molecule clearance in ultrafiltration/diafiltration in relation to protein interactions: Study of citrate binding to a Fab
Authors: Harinarayan C. , Skidmore K. , Kao Y. , Zydney A.L. , van Reis R. 
Published: November 2008

AbstractUltrafiltration/diafiltration (UFDF) is commonly utilized in the purification of recombinant proteins to concentrate and buffer exchange the product. It is often the final step in the purification process, placing the protein in its final formulation and clearing small molecules introduced in upstream purification steps. This article presents a case study of reduced small molecule clearance in ultrafiltration/diafiltration of an antigen‐binding fragment of a monoclonal antibody. Citrate, a commonly utilized small molecule in downstream processes, is shown to have reduced clearance due to specific interactions with the protein product. The study presents process solutions and utilizes a simple model to characterize clearance of small molecules which exhibit interactions with product protein. Biotechnol. Bioeng. 2009;102: 1718–1722. © 2008 Wiley Periodicals, Inc.
Metabolic control analysis of an enzymatic biofuel cell
Authors: Glykys Doris J. , Banta Scott 
Published: November 2008

AbstractMetabolic control analysis (MCA) is an analytical technique that aims to quantify the distribution of control that enzymes exhibit over the steady‐state fluxes through a metabolic network. In an enzymatic biofuel cell, the flux of interest is the electrical current generated by the system. Regardless of transport limitations and other constraints, kinetic limitations can become potential bottlenecks in the operation of a biofuel cell. We have used an indirect approach to MCA to investigate a common osmium‐mediated glucose oxidase/laccase enzymatic biofuel cell. The results of the analysis show that the control of the electron flux strongly depends on the total mediator concentrations and the extent of polarization of the individual electrodes. The effect of varying oxygen concentrations is also examined, as oxygen is required for the cathode, but it participates in a non‐productive reaction at the anode. Under normal operating conditions the electrodes will be highly polarized and will both contain high mediator concentrations. This configuration will result in a dominant FCC at the anode, and the conditions that are needed for balanced flux control between the anode and cathode are explored. As increasingly complex bioelectrocatalytic systems and architectures are envisioned, MCA will be a valuable framework to facilitate their design and subsequent operation. Biotechnol. Bioeng. 2009;102: 1624–1635. © 2008 Wiley Periodicals, Inc.
Identification of the limitations on recombinant gene expression in CHO cell lines with varying luciferase production rates
Authors: Mead Emma J. , Chiverton Lesley M. , Smales C. Mark , von der Haar Tobias 
Published: November 2008

AbstractMammalian cell lines are currently employed as one of the main cellular factories for the expression of recombinant protein‐based drugs. The establishment of high‐producing cell lines typically begins with a heterogeneous starter population of cells, from which the highest producing cells are selected via empirical approaches. This approach is time consuming, and is likely to encounter natural upper limits imposed by the inherent biology of the cell lines in question. In an attempt to understand both the nature of the variability in populations of cells transfected with recombinant protein encoding DNA and the natural mechanisms of productivity limitation, we developed protocols for the detailed investigation of gene expression pathways in such cell lines. This novel approach was then applied to a set of clonal CHOK1 cell lines producing recombinant luciferase with varying productivities. Our results show that the initial limitation in these cell lines is at the transcriptional level, however in the highest producing cell line post‐translational mechanisms affecting both protein turnover and protein folding become severely limiting. The implications for the development of strategies to engineer cells for enhanced recombinant protein production levels are discussed. Biotechnol. Bioeng. 2009;102: 1593–1602. © 2008 Wiley Periodicals, Inc.
Co‐Metal‐Free Enantioselective Conjugate Addition Reactions of Zinc Reagents
Authors: Ay Sefer , Nieger Martin , Bräse Stefan 
Published: November 2008

AbstractAsymmetric conjugate addition of diethylzinc to cinnamaldehyde in a co‐metal‐free fashion by using N,O‐ligands with planar and central chirality is described. Different modulations of the ligand structure, including several combinations of the chiral units, indicate that a [2.2]paracyclophane backbone is essential for the activity and the enantioselectivity of the generated active catalyst. By using the optimized ligand, an isolated yield of 90 % was obtained with up to 99 % ee.
Potential of different techniques of preferential crystallization for enantioseparation of racemic compound forming systems
Authors: Polenske Daniel , Lorenz Heike , Seidel‐Morgenstern Andreas 
Published: November 2008

AbstractRecently the feasibility of preferential crystallization for enantioseparation of racemic compound forming systems has been demonstrated (Lorenz et al., Application of preferential crystallization to resolve racemic compounds in a hybrid process. Chirality 2006;18:828–840; Polenske et al., Separation of the propranolol hydrochloride enantiomers by preferential crystallization: thermodynamic basis and experimental verification. Cryst Growth Des 2007;7:1628–1634). Here, the development and the potential of an efficient separation process operated via two different techniques of preferential crystallization are studied: (1) seeded isothermal preferential crystallization and (2) auto‐seeded polythermal preferential crystallization. Both techniques were investigated in the batch and in the cyclic operation mode. On the example of mandelic acid as a typical racemic compound forming system, it is demonstrated that a cyclic auto‐seeded polythermal process is feasible and significantly more efficient than the seeded isothermal one. Chirality, 2009. © 2008 Wiley‐Liss, Inc.