bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of Synthetic Polyanions on 3T3-L1 Fibroblast Proliferation Stimulated by Fibroblast Growth Factors
Authors: Hatanaka Kenichi , Ohtsuki Takashi , Kunou Megumi 
Published: April 2006

Abstract
Effects of synthetic polyanions on the mitogenic activity of fibroblast growth factors were investigated. Poly(vinylsulfonate) contributed to potentiate the activity of the acidic fibroblast growth factor, while the carboxyl group was quite effective for basic fibroblast growth factor.
A Total Synthesis of (±)-Sativene via High-Pressure Diels-Alder Route
Authors: Hatsui Toshihide , Hashiguchi Tomokazu , Takeshita Hitoshi 
Published: April 2006

Abstract
Sativene, a metabolite of Helminthosporium sativum or Abies magnifica, was synthesized in the racemic form from 2,3-dimethyl-1,3-cyclohexadiene and methyl coumalate via an inversely-electron-demanded high-pressure Diels-Alder reaction in five steps.
Simultaneous Multielement Analysis of Rock Samples by Inductively Coupled Plasma Mass Spectrometry Using Discrete Microsampling Technique
Authors: Fujimori Eiji , Sawatari Hideyuki , Hirose Akio , Haraguchi Hiroki 
Published: April 2006

Abstract
Simultaneous multielement analysis of geological standard rock samples (JG-1 and JB-2) has been successfully performed by inductively coupled plasma mass spectrometry using a discrete microsampling technique. In this technique only 100 μl sample solution was used for simultaneous determination of 5–10 elements in solution.
Characterization of High Valent Iron Porphyrin in Catalytic Reaction by Iron(III) Tetrapentafluorophenylporphyrin
Authors: Fujii Hiroshi 
Published: April 2006

Abstract
High valent species formed from iron(III) meso-tetra-(pentafluorophenyl)porphyrin was first prepared in dichloromethane and characterized by low-temperature UV-vis absorption spectra, proton NMR and ESR. These measurements showed the formation of oxo iron(IV) porphyrin π-cation radical, not iron(V) porphyrin.
27Al NMR Study of Coordination States of Aluminum-tri-sec-butoxide Dissolved in Diacetone Alcohol
Authors: Tadanaga Kiyoharu , Minami Tsutomu , Tohge Noboru 
Published: April 2006

Abstract
27Al NMR spectra of aluminum-tri-sec-butoxide (Al(O-sec-Bu)3) dissolved in several molar ratios of diacetone alcohol were measured. The spectrum of Al(O-sec-Bu)3 dissolved in diacetone alcohol showed the formation of five-coordinated structural units from original four-coordinated ones. This structural change revealed that diacetone alcohol chemically modified the Al-alkoxide and reduced the reactivity of the alkoxide.
Conjugated Molecular System of Photochromism and Electrochromism. Photoelectrochemical Behavior of Nitrospirobenzopyran at Low Temperature
Authors: Zhi Jin-Fang , Baba Ryo , Hashimoto Kazuhito , Fujishima Akira 
Published: April 2006

Abstract
1,3,3-trimethyl-6-nitrospiro(2H-1-benzopyran-2,2′-indoline) in DMF at −42 °C was found to constitute a new “three state” photoelectrochemical molecular system. This behavior is attributed to having a common species produced from either photoinduced open-ring or closed-ring isomers by electron transfer, namely, a radical anion of the closed-ring by reduction and an open-ring isomer by oxidation.
New Method for the Preparation of Alkoxycarbene Complexes of Chromium, Molybdenum, and Tungsten Using Sulfonium Salts
Authors: Nakamura Takako , Matsuyama Haruo , Iyoda Masahiko 
Published: April 2006

Abstract
Alkylation of tetramethylammonium acylate complexes of chromium, molybdenum, and tungsten with alkyldiphenylsulfonium salts readily proceeds under mild conditions to afford alkoxycarbene complexes containing a variety of functional groups in good yields.
Formation of Dithioacetals by Treatment of Sulfoxides Carrying α-Hydrogens with Magnesium Amides
Authors: Kobayashi Kazuhiro , Kawakita Masataka , Mannami Tohru , Morikawa Osamu , Konishi Hisatoshi 
Published: April 2006

Abstract
Sulfoxides carrying α-hydrogens were allowed to react with magnesium amides generated in situ by the treatment of ethylmagnesium bromide with secondary amines such as 2,2,6,6-tetramethylpiperidine or diisopropylamine in diethyl ether to give the corresponding dithioacetals in moderate to good yields.
Isomerization of the (Z)-Enyne Unit to the (E)-Enyne Unit. Conversion of Laureatin to (E)-Isolaureatin
Authors: Ishihara Jun , Kanoh Naoki , Fukuzawa Akio , Murai Akio 
Published: April 2006

Abstract
The (Z)-enyne compound bearing the acetylene part protected with dicobalt octacarbonyl, derived from laureatin, was reacted with trifluoromethanesulfonic acid to afford exclusively the corresponding (E)-derivative related to (E)-isolaureatin.
Chiral Lattice-Controlled Asymmetric Photoisomerization of (2-Cyanoethyl)cobaloximes in the Solid State
Authors: Ohgo Yoshiaki , Arai Yoshifusa , Hagiwara Mieko , Takeuchi Seiji , Kogo Hidenori , Sekine Akiko , Uekusa Hidehiro , Ohashi Yuji 
Published: April 2006

Abstract
Solid-state asymmetric photoisomerization of 2-cyanoethylcobaloxime complexes occurred to afford optically active 1-cyanoethylcobaloxime complexes with moderate to high enantioselectivities (∼82%ee). The X-ray crystal structure analysis of (R)-2-phenylglycinol-coordinated complex revealed that the 2-cyanoethyl group is forced to take a chiral conformation by chiral crystal lattice. The enantioselection mechanism is also discussed based on the X-ray results.
Atomic Force Microscopy of Glass Surface Modified with Silane Coupling Agent Containing Fluorocarbon Chain
Authors: Yoshino Norio 
Published: April 2006

Abstract
Atomic force microscopic (AFM) data of glass surface modified with silane coupling agent containing fluorocarbon chain, (1H,1H,2H,2H-henicosafluorododecyl)trimethoxysilane, were obtained. Fluorocarbon chains on the modified glass surface were found to stand close together. Double- or triple-layer of the silane on the modified surface was observed mainly near the border between modified- and unmodified-area.
Fulgenates. A New Class of Fulgide-Related Thermally Irreversible Photochromic System
Authors: Yokoyama Yasushi , Sugiyama Kazuhiro , Yamada Shintaro , Takimoto Hitoshi , Kurita Yukio 
Published: April 2006

Abstract
Thermally irreversible photochromic properties of indolylfulgenates, i.e. 2-alkylidene-3-[1-(1,2-dimethyl-3-indolyl)alkylidene]succinate esters were examined. A large indolylalkylidene group reduced the relative ratio of the colored species at the photostationary state of UV irradiation. Introduction of an adamantylidene group increased the bleaching quantum yield. The absorption maximum wavelengths of the colorless and colored species were shorter than those of the corresponding indolylfulgide.
Synthesis and Properties of 1,2:5,6-Bis(ethylenedithio)pyracylene
Authors: Tani Hiroyuki , Masumoto Kazunori , Azuma Nagao , Ono Noboru 
Published: April 2006

Abstract
A novel π-donor, 1,2:5,6-bis(ethylenedithio)pyracylene (2), was prepared by dithioacetalization of 1,5-pyracenedione with 1,2-ethanedithiol followed by ring expansion on treatment with tellurium tetrachloride. 2 showed two reversible low oxidation potentials by cyclic voltammetry. Single crystal X-ray analysis of 2 revealed unique three dimensional donor networks.
Brodioside B, a Novel (20R,22S)-Spirostanol Tetrasaccharide from Brodiaea californica Tubers
Authors: Nakamura Osamu , Mimaki Yoshihiro , Sashida Yutaka , Nikaido Tamotsu , Ohmoto Taichi 
Published: April 2006

Abstract
A novel (20R,22S)-spirostanol tetrasaccharide, named brodioside B, was isolated from Brodiaea californica together with a new (25S)-ruscogenin tetrasaccharide, named brodioside A. Their structures were determined by extensive 2D NMR analysis and hydrolysis. Brodiosides A and B were active as a cyclic AMP phosphodiesterase inhibitor.
Correlation between Regiospecific Dioxygen Incorporation into 2,6-Di-tert-butylphenols and Their Redox Potential
Authors: Nishinaga Akira , Yano Masafumi , Kuwashige Tomoyoshi , Maruyama Kazushige , Mashino Takahiro 
Published: April 2006

Abstract
The position of O2 incorporation into 2,6-di-tert-butylphenols in the presence of Co(salpr) is correlated to redox potential Eo (mV) of phenolate anion/phenoxy radical couple: Eo &gt; −645, ortho position; Eo &lt; −650, para position. No phenoxy radical intermediate is involved for the oxygenation of the phenolate anion with Eo &gt; −645 Å mV.
The Formation of 1,4-Quinones by Oxovanadium(IV)-Complexes Catalyzed Aerobic Oxygenation of Fused Aromatic Compounds
Authors: Takai Toshihiro , Hata Eiichiro , Mukaiyama Teruaki 
Published: April 2006

Abstract
In the presence of a catalytic amount of oxovanadium(IV) complexes coordinated with 1,3-diketone ligands, fused aromatic compounds such as naphthalenes and naphthol derivatives are smoothly oxygenated into the corresponding 1,4-naphthoquinones by combined use of molecular oxygen and crotonaldehyde under an atmospheric pressure.
Flocculation of Egg-Phosphatidylcholine Liposomes under Drift Flow Brought on Gravity
Authors: Matsumura Hideo 
Published: April 2006

Abstract
Flocculation behavior of large egg-phosphatidylcholine liposomes caused by Ca2+ under the influence of gravitational force due to the density difference between liposomes and medium has been studied. The greater the difference in density, the more closely packed are the structures or the flocs obtained.
An Efficient Epoxidation with Molecular Oxygen Catalyzed by Iron Complex of Multidentate N-Heterocyclic Podand Ligand. Additive Effect of 4-Ethoxycarbonyl-3-methyl-2-cyclohexen-1-one
Authors: Moriuchi Toshiyuki , Hirao Toshikazu , Ohshiro Yoshiki , Ikeda Isao 
Published: April 2006

Abstract
Coexistence of 4-ethoxycarbonyl-3-methyl-2-cyclohexen-1-one facilitated the epoxidation reaction of styrenes with molecular oxygen catalyzed by FeCl2 and the multidentate N-heterocyclic podand ligand, N,N′-bis{2-(4-imidazolyl)ethyl}-2,6-pyridinedicarboxamide.
A New Family of Liquid Crystals with Low Melting Points. 4-(trans-4-Alkylcyclohexyl)-alkylbenzenes
Authors: Sugita Nami , Araya Kotaro 
Published: April 2006

Abstract
Four homologues of 4-(trans-4-alkylcyclohexyl)-alkylbenzene were prepared and their liquid crystal properties were investigated. These homologues comprise an interesting and useful family of nematic liquid crystals with melting points below 0 °C. Eutectic mixture of these four compounds gave a stable nematic phase at temperatures between −22.8 and −50.2 °C.
Antioxidants, Supplements, and Parkinson's Disease
Authors: Weber Cynthia A , Ernst Michael E 
Published: April 2006

Objective: To review the use of antioxidants and other supplements for the prevention and treatment of Parkinson's disease (PD). Data Sources: Biomedical literature was accessed through MEDLINE (1996–June 2005); key search terms included Parkinson's disease, coenzyme Q10 (CoQ10), antioxidants, supplements, and glutathione. Pertinent references cited in those articles were also evaluated for inclusion in this review. Data Synthesis: Three main antioxidants or supplements have been studied for use in the prevention or treatment of PD: tocopherol, CoQ10, and glutathione. These agents have been studied because of their potential to alter the course of 2 common theories of PD pathogenesis: free radical generation and mitochondrial complex-1 deficiency. The literature search revealed 3 large clinical studies of tocopherol (2 observational, 1 prospective randomized), 4 trials of CoQ10, and 1 study of glutathione. With the exception of the large observational studies with tocopherol and one study of CoQ10 that enrolled 80 patients, each of the other studies retrieved included fewer than 30 patients and were conducted for 3 months or less. Antioxident supplementation, in particular tocopherol, did not appear to alter the course of PD. However, in 2 of the studies of CoQ10 and in the study of glutathione, a small but statistically significant improvement in PD symptoms was observed. Conclusions: At present, antioxidants and supplements appear to have a limited role in the prevention or treatment of PD. Of those reviewed here, CoQ10 appears to provide some minor treatment benefits. More study is necessary to determine whether CoQ10 has a significant role as primary or adjunctive therapy in PD.
Decline-Curve Analysis Considering Nonlaminar Flow in Dual-Porosity Systems
Authors: Rodríguez-Román J. , Camacho-Velázquez R. 
Published: April 2006

Summary
Most of the theoretical work on decline-curve analysis with non-laminar flow in the reservoir considers either a dry gas or liquid flow in a homogeneous system. The purpose of this work is to analyze decline curves considering the non-Darcy flow effect in the reservoir for a slightly-compressible-liquid flow in dual-porosity systems at constant wellbore pressure.
The transient and boundary-dominated flow periods are examined by means of computer results generated with a finite-difference simulator. Analytical expressions of velocity and wellbore rate are presented for the first time in this paper. These equations contain the laminar-flow solution as a particular case. A method is proposed to identify the presence of inertial effects by plotting d[log(q)]/d[log(t)] against log(t).
The method for area calculation under laminar conditions produces a good approximation for a reservoir under nonlaminar flow. However, the presence of inertial effects distorts the shape of decline curves, resulting in erroneous estimates of wellbore and reservoir parameters by type-curve analysis with laminar decline curves.
The utility of the methodology presented in this work is illustrated with synthetic examples.
Correlations for Hydrocarbon-Gas Viscosity and Gas Density—Validation and Correlation of Behavior Using a Large-Scale Database
Authors: Londono F. E. , Archer R. A. , Blasingame T. A. 
Published: April 2006

Summary
The focus of this work is on the behavior of hydrocarbon-gas viscosity and gas density. The viscosity of hydrocarbon gases is a function of pressure, temperature, density, and molecular weight, while the gas density is a function of pressure, temperature, and molecular weight. This work presents new approaches for the prediction of gas viscosity and gas density for hydrocarbon gases over practical ranges of pressure, temperature, and composition. These correlations can be used for any hydrocarbon-gas production or transportation operations.
In this work, we created a large database of measured gas viscosity and gas density. This database was used to evaluate existing models for gas viscosity and gas density. We also provide new models for gas density and gas viscosity, as well as optimization of existing models, using our new database.
The objectives of this research are as follows:
To create a large-scale database of measured gas-viscosity and gas-density data. This database will contain all the information necessary to establish the applicability of various models for gas density and gas viscosity over a wide range of pressures and temperatures. To evaluate a number of existing models for gas viscosity and gas density. To develop new models for gas viscosity and gas density using our research database; these models are proposed and validated.
For this study, we created a large database from existing sources available in the literature. The properties in our database include composition, viscosity, density, temperature, pressure, pseudoreduced properties, and the gas compressibility factor. We use this database to evaluate the applicability of existing models used to determine hydrocarbon-gas viscosity and hydrocarbon-gas density (or, more specifically, the gas z-factor). Finally, we developed new models and calculation approaches to estimate the hydrocarbon-gas viscosity, and we also provide an optimization of the existing equations of state (EOS) typically used for for the calculation of the gas z-factor.
Crude-Oil Emulsions: A State-Of-The-Art Review
Authors: Kokal Sunil 
Published: April 2006

Summary
The formation of emulsions during oil production is a costly problem, both in terms of chemicals used and production lost. This paper discusses production and operational problems related to crude-oil emulsions and presents a review that will be useful for practicing engineers.
The first part of this paper presents why emulsions form during oil production, the types of emulsions encountered, and new methods for characterizing them. Crude-oil emulsions are stabilized by rigid interfacial films that form a "skin" on water droplets and prevent the droplets from coalescing. The stability of these interfacial films, and hence, the stability of the emulsions, depends on a number of factors, including the heavy material in the crude oil (e.g., asphaltenes, resins, and waxes), solids (e.g., clays, scales, and corrosion products), temperature, droplet size and droplet-size distribution, pH, and oil and brine composition. The effects of these factors on emulsion stability are reviewed within this paper.
The second part of this paper presents methods to tackle crude-oil emulsions. The focus is on the destabilization of emulsions and the demulsification process. Emulsions are destabilized by increasing temperature and residence time, removal of solids, and controlling emulsifiers. The mechanisms involved in demulsification (e.g., flocculation, aggregation, sedimentation, creaming, and coalescence) are discussed in terms of the stability of the interfacial films. The methods involved in demulsification—including thermal, mechanical, electrical, and chemical are also presented. Experience and economics determine which methods are used, and to what degree, for emulsion treatment.
Finally, a section on field applications also is included that should be useful for the practicing engineer who deals with emulsions either regularly or on a limited basis. Herein the field-emulsion treatment program is discussed, and more importantly, methods to prevent emulsion problems are highlighted. Recommendations are made for reducing and optimizing demulsifier dosage and controlling emulsion problems.
New Friction Factor Correlations of Non-Newtonian Fluid Flow in Coiled Tubing
Authors: Zhou Y. , Shah S. N. 
Published: April 2006

Summary
This paper presents a complete set of friction-factor correlations for both Newtonian and non-Newtonian fluids in laminar and turbulent flow in coiled tubing. The friction-factor correlation for non-Newtonian fluids in laminar flow is based on theoretical analysis and numerical solutions of the flow equations of a power-law-model fluid in curved pipes. The empirical correlation for non-Newtonian fluids in turbulent flow is based on full-scale experiments of polymeric-fluid systems in various 1-, 11/2-, and 23/8-in. coiled-tubing reels. To consider the effect of pipe roughness in coiled tubing, a modified correlation is proposed by combining the Srinivasan et al. correlation (Srinivasan et al. 1970) for smooth, curved pipe and the Chen correlation (Chen 1979) for rough, straight pipe. Examples are given to illustrate the applications and accuracies of the newly developed correlations.
A Circulating-Foam Loop for Evaluating Foam at Conditions of Use
Authors: Hutchins Richard D. , Miller Matthew J. 
Published: April 2006

Summary
Foam stability is an important parameter for foam fracturing. Bench-top testing is useful for screening but does not address the necessary conditions of temperature, pressure, pH [particularly with carbon dioxide (CO2) systems], and dynamic-flow conditions that can have unexpected influence on the foam's performance.
A laboratory apparatus has been constructed for measuring the rheology of circulating-foam fluids to 400°F and 3,000 psi. The apparatus is equipped with a circulation pump, view cells, foam generator, mass flowmeter, and piping for loading a foam of the desired quality using either nitrogen (N2) or CO2. The foam rheometer is intended for evaluation of foam stability with time and comparison of various foam formulations for application in foam fracturing.
The foam loop was designed to mimic shear rates found in a fracture or reservoir, which are typically 200 s−1 or less. The rheology is measured by monitoring the pressure drop across a 20-ft length of ¼-in. tubing maintained at temperature in an oven. Flow rate is continuously adjusted, to ensure a constant shear rate in the tubing, by the software using continuous mass-flowmeter input.
Results relating to CO2 and N2 foams are discussed with emphasis on foam persistence, bubble size and population, and the rheological behavior with time. Temperature, pressure, and additives affect both foam texture and foam stability. The adoption of a standard technique patterned after this work for evaluating foam rheology could impact the use and development of foam fluids in the future.
Binary Corrosion Inhibitors Offer Improved Corrosion Control
Authors: Zaid Gene H. , Sanders Donald W. 
Published: April 2006

Summary
An improvement has been made in anticorrosion chemicals for oilfield use. A binary corrosion inhibitor that combines an epoxy resin and an amine curing agent has been patented and field proven. The proper application of this unique combination of chemicals forms a bond with the oxide film present on downhole metal surfaces. The result is a corrosion-inhibitor barrier that is more tenacious than conventional polar-filming amines, reducing application frequency and labor costs and, even more important, downhole failures. The binary corrosion inhibitor is also an improvement over, and is more versatile than, other epoxy-amine products.
Determination of Gas-Diffusion and Interface-Mass-Transfer Coefficients for Quiescent Reservoir Liquids
Authors: Civan Faruk , Rasmussen Maurice L. 
Published: April 2006

Summary
A physically and mathematically rigorous transient-state equilibrium diffusion model is applied for simultaneous determination of the gas-diffusion and interface-mass-transfer coefficients from pressure decline by dissolution of gas in quiescent liquids involving petroleum reservoirs. The short-and long-time analytical solutions of this model are reformulated to enable direct determination of the best-estimate values of these parameters by regression of experimental data. Typical experimental data are then analyzed by means of the present improved methods, and the values obtained are compared with the re-ported values. The present methodology is proven practical and yields unique and accurate parameter values.