bluuebunny/crossref_metadata_2025_split huggingface dataset:
Theoretical ab initio study of ranitidine
Authors: Martins Jão B. L. , Perez Marco A. , Silva Carlos H. T. P. , Taft C. A. , Arissawa M. , Longo Elson , Mello P. C. , Stamato Fulvia M. L. G. , Tostes J. G. R. 
Published: October 2002

AbstractThe presence of a heterocyclic ring containing a basic center linked via a methylene chain to a substituted guanidine or thiourea polar side chain, such as found in the H2‐antagonist metiamide, which has an imidazole heterocyclic ring, has often been identified as one of the requirements for H2‐antagonist activity. In ranitidine, on the other hand, the imidazole ring is substituted for a furan ring, yielding a more active biological H2 antagonist. In this work, we have used the ab initio Hartree–Fock (HF) and second‐order Møller–Plesset (MP2) methods in order to investigate the open and folded ranitidine conformations, of the type observed in metiamide. Five basis sets (3‐21G, 3‐21+G**, 6‐31G, 6‐31+G**, and 6‐31+G**) were used in order to obtain fully optimized geometric parameters that indicated good agreement with the experimental crystallographic data. We have also investigated in this work the effects of solvents in both ranitidine and metiamide. Monocationic ranitidine was also investigated. All our results, indicate that, as in metiamide, the folded conformation is also preferred. We have investigated Mulliken and natural bond order (NBO) charge distributions, electrostatic and hydrogen bond effects on stabilizing the conformations and discussed the interactions of ranitidine with the biological receptor. © 2002 John Wiley & Sons, Inc. Int J Quantum Chem, 2002
A rapid and efficient mass spectrometric method for the analysis of explosives
Authors: Evans C. S. , Sleeman R. , Luke J. , Keely B. J. 
Published: October 2002

AbstractThe high explosives trinitrotoluene, nitroglycerine, pentaerythritol tetranitrate and hexahydro‐1,3,5‐trinitro‐1,3,5‐triazine are efficiently ionised under negative ion atmospheric pressure chemical ionisation (APCI) conditions. The limit of detection is improved, in some cases by several orders of magnitude, by complexation with chlorine demonstrating this to be a highly suitable method for enhancing the detection capabilities for explosives. The spectra produced from introduction of the analytes in a liquid matrix, with and without chlorine present, contain a number of ions that arise through secondary processes including breakdown and adduct formation. Sample introduction into an APCI source in air, via a heated‐plate inlet with a supplementary feed of dichloromethane, produces improved response for the chloride adducts of the analytes and minimises their decomposition during analysis. The tandem mass spectra produced from the chloride adducts are simple. Optimisation of the trapping parameters of the ion trap detector enhances selected transitions, yields highly reproducible spectra and improves the limits of detection for MS/MS analysis. Copyright © 2002 John Wiley & Sons, Ltd.
On the detailed mechanisms of collision‐induced dissociation experiments performed by electrospray ion trap
Authors: Catinella Silvia , Pelizzi Nicola , Barboso Silvia , Favretto Donata , Seraglia Roberta , Traldi Pietro 
Published: October 2002

AbstractThe product ion spectra obtained by electrospray ionization (ESI) ion trap instruments exhibit a higher number of fragment ions than those achieved by other ion‐trap‐based systems, indicating the presence of more effective energy deposition mechanisms. This behavior can be attributed to several different reasons, among which different initial internal energy of the precursor ions, pre‐activation due to collisions taking place outside the trap, different target gas mixtures inside the trap, and different ion trap geometry were considered. Data obtained from experiments using a triple quadrupole instrument, CI‐ion trap, and ESI‐ion trap have been compared. The results so achieved seem to indicate that the presence inside the trap of neutral molecules of the solvent employed for the ESI process have a relevant role, promoting high energy deposition in the colliding ions. Copyright © 2002 John Wiley & Sons, Ltd.
Rapid analysis of intact phospholipids from whole bacterial cells by matrix‐assisted laser desorption/ionization mass spectrometry combined with on‐probe sample pretreatment
Authors: Ishida Yasuyuki , Madonna Angelo J. , Rees Jon C. , Meetani Mohammed A. , Voorhees Kent J. 
Published: October 2002

AbstractMatrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOFMS), utilizing an on‐probe sample pretreatment, was applied to the rapid and direct detection of intact phospholipids from whole bacterial cells. The sample preparation procedure involved depositing growing bacterial colonies from culture dishes directly onto the MALDI probe followed by treatment of the sample spot with a 3 µL aliquot of an aqueous 0.05 M solution of sodium iodide prior to the addition of a 2,5‐dihydroxybenzoic acid (DHB) matrix solution (ca. 8 mg dissolved in 70% acetonitrile/30% H2O containing 0.1% of trifluoroacetic acid). The MALDI spectra obtained from whole bacteria cells showed a series of ions generated from bacterial phospholipids, such as phosphatidylethanol‐amines (PEs) and phosphatidylglycerols (PGs), which were clearly observed as well‐resolved peaks. The ranges of the observed total carbon numbers in two acyl groups for PEs and PGs (30–36 and 33–36, respectively) were in good agreement with those reported previously. Furthermore, the distinct discrimination of four species of the Enterobacteriaceae family cultured identically was achieved by using principal components analysis (PCA) conducted on the relative peak intensities of phospholipids observed from the MALDI spectra. Copyright © 2002 John Wiley & Sons, Ltd.
Selected ion flow tube studies of the reactions of H3O+, NO+ and O2+ with the anaesthetic gases halothane, isoflurane and sevoflurane
Authors: Wang Tianshu , Smith David , Španěl Patrik 
Published: October 2002

AbstractWe have carried out a study of the reactions of H3O+, NO+ and O2+, the commonly used precursor ions for selected ion flow tube mass spectrometry (SIFT‐MS), with three anaesthetic gases, halothane, isoflurane and sevoflurane. The motivation for this study was to provide the necessary kinetic data that would allow the quantification of these anaesthetic gases in operating theatre air and in the breath of theatre staff and post‐operative patients. A clear negative result from these experiments is that NO+, although undergoing the simplest chemistry, is unsuitable for this SIFT‐MS application. However, although the ion chemistry of H3O+ and O2+ with these compounds is very complex, there being several product ions in each reaction, many of which react rapidly with water molecules, monitor ions have been identified for all three anaesthetic gases when using H3O+ and O2+ as precursor ions. The detailed ion chemistry is discussed and the specific monitor ions are indicated. Hence, the feasibility of on‐line breath monitoring is demonstrated by simple examples. These studies have opened the way to measurements in the clinical environment. Copyright © 2002 John Wiley & Sons, Ltd.
Visualizing reductive dechlorination in support of intrinsic bioremediation using multivariate plots and GIS
Authors: Seagren Eric A. , Clarke Raymond , Johnson Mark 
Published: October 2002

AbstractDemonstrating intrinsic bioremediation requires not only that the right types of evidence be gathered, but
also that those data be analyzed at an appropriate level of detail and presented in a manner that clearly
illustrates the key trends to the target audience. The goal of this study was to develop one type of multivariate
pattern diagram, the pie diagram, for clearly and efficiently presenting data demonstrating the occurrence of
reductive dechlorination at sites contaminated by chlorinated ethenes. The pie diagrams were created using
normalized ethenes molar concentrations to estimate and illustrate the changes in the concentrations of
contaminants and metabolic intermediates that could be attributed to biodegradative processes. Spatial
pie‐diagram maps illustrating the normalized chlorinated‐ethenes data were produced using
geographic information system (GIS) software. Application of this visualization tool is demonstrated
using an example data set and is compared with a conventional x‐y graph of the data. The trends elucidated
on the basis of the pie diagrams, coupled with additional site evidence of natural attenuation (e.g.,
electron donor and acceptor data), are shown to provide a consistent interpretation of the site data. ©
2002 Wiley Periodicals, Inc.
Evaluation of a soil‐amendment process demonstration for reducing the bioavailability of lead
Authors: Barth Edwin F. , Evans Mark 
Published: October 2002

AbstractThe U.S. Environmental Protection Agency (EPA) evaluated an in‐situ application of a
soil‐amendment process at a residential site that was contaminated with lead. The goal of the evaluation
was to determine if the soil‐amendment process resulted in lower concentrations of bioavailable lead in the
contaminated soils. The relative bioavailability of lead (bioaccessible lead) was measured by an in
vitro test procedure that uses a highly acidic extraction procedure to simulate human digestive processes. The
soil‐amendment demonstration showed that the 11.2 percent mean reduction in bioavailable lead concentration
between untreated and treated soils was not statistically different. © 2002 Wiley Periodicals, Inc.
Reducing salinity and organic contaminants in the Pearl Harbor dredged material using soil amendments and plants
Authors: Hue N. V. , Campbell S. , Li Q. X. , Lee C. R. , Fong J. 
Published: October 2002

AbstractPhytoremediation is an emerging technique that can be used to economically remediate sites contaminated with
trace elements and/or man‐made organic contaminants. This technique was used on Pearl Harbor (Oahu,
Hawaii) dredged material (PHDM) containing polycyclic aromatic hydrocarbons (PAHs) and
some heavy metals. The dredged material was first amended with a high‐calcium soil (Waialua
Mollisol) and a biosolids‐based compost at different proportions to yield varying salinity levels. A
mixture that yielded an electrical conductivity (EC, a measure of salinity) of the saturated paste
extract of 15 to 20 dS/m was identified and used to evaluate the salt tolerance of five plant species. Relative
germination and one‐month‐old biomass indicated that common bermuda grass (Cynodon
dactylon), seashore paspalum (Paspalum vaginatum), beach pea
(Vigna marina), and cow pea (Vigna unguiculata) can produce
at least 40 percent of biomass of the control at an EC of approximately 18 dS/m, suggesting the four plants are
relatively salt tolerant. In contrast, Desmodium intortum either did not germinate or died within
two weeks after germination at the same salinity level. A subsequent greenhouse experiment, using mixtures of the
PHDM (0 or 25 percent dry weight), organic amendments (10 percent leucaena green manure or
biosolids‐based compost), and a Mollisol (65 or 90 percent dry weight) in 6‐liter pots
containing 4 kilograms of material yielded the following results: (1) A combination of transplanted
seashore paspalum, seeded bermuda grass, and seeded beach pea was effective in taking up sodium (Na),
thereby reducing salinity and making the medium more amenable to diversified microbes and plants, which may be
effective PAH degraders; (2) total PAH concentration was reduced by about 30 percent after three
months of active plant growth, but degradation of individual PAH members varied significantly, however;
(3) leguminous green manure, as a soil amendment, was more effective than compost for use in bio‐
and/or phytoremediations; and (4) soil amendments, when applicable, could supplement living
plants in reducing organic contaminants, such as PAHs. © 2002 Wiley Periodicals, Inc.
Construction of a permeable reactive barrier in a residential neighborhood
Authors: Richards Peter 
Published: October 2002

AbstractIn June 2001, the Massachusetts Department of Environmental Protection (DEP) installed a permeable
reactive barrier (PRB) within a roadway in Needham, Massachusetts, to treat a plume of chlorinated
solvents migrating toward two public water‐supply wells located in the adjacent town of Wellesley,
Massachusetts. The solvents originated from an electronics manufacturer located approximately 2,300 feet upgradient
of the roadway and 5,200 feet upgradient of the public supply wells. Chlorinated solvents, primarily trichloroethene
(TCE), had migrated past the roadway to within 300 feet of the public supply wells. Two contaminant
transport models prepared by the DEP's design contractor and the EPA indicated that the plume would reach the
well field if no response actions were taken. To mitigate the future impact to the municipal well field, the DEP
decided to install a PRB composed of zero‐valent granular iron across the path of the plume along Central
Avenue in Needham. Though several dozen PRBs have been installed at sites worldwide and the technology is no longer
considered innovative, the application of the technology in a roadway that receives 17,000 vehicles per day within a
residential neighborhood is unique and presented difficulties not typically associated with PRB installations. The
Needham PRB was also one of the first zero‐valent iron PRBs installed using the slurry trench method to treat
chlorinated compounds. © 2002 Wiley Periodicals, Inc.
Biofiltration of airstreams contaminated with MTBE
Authors: Singh Harvinder , Sanders Dee Ann , Veenstra John N. 
Published: October 2002

AbstractThe treatment of groundwater contaminated with low concentrations of methyl tertiary butyl ether
(MTBE) is of nationwide concern. Many treatment techniques include removing MTBE vapors from
groundwater, resulting in airstreams that require treatment. One method used for air‐phase MTBE
treatment is biofiltration. In a biofilter, the vapors pass through a reactor that contains
MTBE‐biodegrading organisms attached to a porous media. This article reports the results of a
biofiltration study to treat air contaminated with MTBE at concentrations of 0.2 to 0.33 mg/l,
concentrations frequently encountered in the field. The results indicate that MTBE removal at these low
concentrations is not as efficient as removals seen at higher concentrations. Activated carbon was shown to be
a superior biofiltration medium, compared with media that do not adsorb MTBE vapors. Activated carbon was
especially helpful in treatment shock loads of MTBE. © 2002 Wiley Periodicals, Inc.
Vibration and stability control of robotic manipulator systems consisting of a thin‐walled beam and a spinning tip rotor
Authors: Song Ohseop , Librescu Liviu , Kwon Hyuck‐Dong 
Published: October 2002

AbstractVibration and stability feedback control of a robotic manipulator modeled as a cantilevered

thin‐walled beam carrying a spinning rotor at its tip is investigated. The control is achieved via

incorporation of adaptive capabilities that are provided by a system of piezoactuators, bonded or embedded into

the host structure. Based on converse piezoelectric effect, the piezoactuators produce a localized strain field

in response to an applied voltage, and as a result, an adaptive change of vibrational and stability response

characteristics is obtained. A feedback control law relating the piezoelectrically induced bending moments at

the beam tip with the appropriately selected kinematical response quantities is used, and the beneficial effects

of this control methodology upon the closed‐loop eigenvibration characteristics and stability boundaries

are highlighted. The cantilevered structure modeled as a thin‐walled beam, and built from a composite

material, encompasses non‐classical features, such as anisotropy, transverse shear, and secondary

warping, and in this context, a special ply‐angle configuration inducing a structural coupling between

flapping‐lagging and transverse shear is implemented. It is also shown that the directionality property

of the material of the host structure used in conjunction with piezoelectric strain actuation capability, yields

a dramatic enhancement of both the vibrational and stability behavior of the considered structural system.

© 2002 Wiley Periodicals, Inc.
Adsorption of polysulphide sealants onto organosilane‐coated aluminium and aluminium substrates
Authors: Rattana Acharawan , Abel Marie‐Laure , Church Simon , Watts John F. 
Published: October 2002

AbstractStudy of the adsorption of polysulphide sealants with oxidized aluminium and oxidized aluminium treated with an organosilane adhesion promoter, γ‐glycidoxypropyltrimethoxysilane (GPS), was achieved using XPS and time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS). The kinetics and thermodynamics of adsorption have been investigated. The kinetics of adsorption were investigated to establish an exposure equilibrium time for the adsorption of polysulphide sealants onto both surfaces. Specimens were treated with polysulphide sealant solutions in toluene and different treatment times ranging from 30 s to 30 min. It was found that a 20 min treatment time allows the adsorption equilibrium of polysulphide sealants on both substrates to be reached. The thermodynamics of adsorption were studied as follows: all substrates have been treated with solutions of polysulphide sealants in toluene in a range of seven concentrations. Thermodynamic studies were carried out by the construction of adsorption isotherms. It was found that the polysulphide sealants adsorbed more on GPS‐treated surfaces; on both surfaces, competition was observed between components present in the sealant formulation. The high‐resolution C 1s XPS spectra were also peak fitted to account for the functional groups known to be present in the sealants and identified from ToF‐SIMS data. Copyright © 2002 John Wiley & Sons, Ltd.
Role of salts on BSA adsorption on stainless steel in aqueous solutions. I. FT‐IRRAS and XPS characterization
Authors: Pradier C. M. , Costa D. , Rubio C. , Compère C. , Marcus P. 
Published: October 2002

AbstractThe understanding of protein interaction with metal surfaces has become a key question for the use of materials in medicine, in the food industry or in marine environment in connection with the process of biofouling. However, the role of the various salts present in natural seawater has never been systematically investigated. In the present work, we studied the adsorption of a protein, bovine serum albumin (BSA), on stainless‐steel surfaces in artificial seawater and in aqueous solutions containing NaCl, NaCl + CaCl2 and NaCl + MgCl2, the total concentration of salts being identical to that of the natural seawater (36 g l−1); the BSA concentration was fixed at 20 mg l−1. After rinsing and drying, the surface was analysed by Fourier transform infrared reflection–adsorption spectroscopy (FT‐IRRAS) and x‐ray photoelectron spectroscopy (XPS). After immersion in aqueous solutions containing NaCl or NaCl + CaCl2 and rinsing in saline solutions, the amount of adsorbed BSA is small. It increases by almost one order of magnitude if the immersion is performed in NaCl + MgCl2 aqueous solution; after 24 h of immersion it reaches a saturation value very close to that attained in natural seawater. At saturation of the stainless‐steel surface by the protein, the XPS metal signals were still detected, suggesting that the protein layer is heterogeneous, leaving patches of the surface almost uncovered. The amount of adsorbed BSA is reduced by almost one order of magnitude when the samples are rinsed in pure, demineralized water due to the dissolution of Mg2+ cations and the elimination of loosely adsorbed proteins. The presence of Mg2+ cations within the BSA layer is confirmed by angle‐resolved XPS analyses. Copyright © 2002 John Wiley & Sons, Ltd.
XPS study of oxides formed on nickel‐base alloys in high‐temperature and high‐pressure water
Authors: Machet A. , Galtayries A. , Marcus P. , Combrade P. , Jolivet P. , Scott P. 
Published: October 2002

AbstractThe aim of this work is to characterize the oxidation behaviour of different nickel‐base alloys exposed to high‐temperature and high‐pressure water for short oxidation times. The behaviour of Alloy 600 (74% Ni, 16% Cr, 9% Fe), Alloy 690 (60% Ni, 30% Cr, 9% Fe) and Alloy 800 (47% Fe, 32% Ni, 21% Cr) exposed to simulated, pressurised water reactor primary water at 325°C has been compared. From the combination of chemical and structural data obtained by XPS, nuclear reaction analysis and scanning electron microscopy, the chemical composition and the morphology of the oxide formed on the surfaces have been determined. All alloys present a duplex oxide layer composed of Fe‐rich crystals in the external layer and an inner Cr‐rich layer that is compact and continuous. The oxide thicknesses were 4–20 nm for Alloy 600 exposed for 0–400 h, 4–40 nm for Alloy 690 exposed for 0–400 h and 4–150 nm for Alloy 800 exposed for 0 to 150 h. The kinetics of oxidation of these samples most probably fit a logarithmic growth equation. Copyright © 2002 John Wiley & Sons, Ltd.
Study of KTiOPO4 surface by x‐ray photoelectron spectroscopy and reflection high‐energy electron diffraction
Authors: Atuchin V. V. , Kesler V. G. , Maklakova N. Yu. , Pokrovsky L. D. , Semenenko V. N. 
Published: October 2002

AbstractStructural and electronic properties of the as‐grown (011) crystal face and the mechanically polished (001) surface of potassium titanyl phosphate (KTiOPO4 or KTP) have been investigated by core‐level x‐ray photoelectron spectroscopy and reflection high‐energy electron diffraction (RHEED). With XPS analysis the original element binding energies, Auger parameters for K 2p3/2 and P 2p core levels, relative element contents and valence band structure have been determined for both crystal cuts. A great depletion of O, K and P in the (011) face with respect to the (001) surface was discovered on comparison of element peak areas. The Ti 2p3/2 peak areas were virtually the same for both cuts investigated. The relative element contents at the (001) surface were very close to the formal composition of KTiOPO4, so it is optimal to use the polished (001) KTP surface cleaned by ion bombardment and the Ti 2p3/2 core level as standards for determination of the chemical composition of doped crystal surfaces. Copyright © 2002 John Wiley & Sons, Ltd.
Effect of sulphur on the formation of graphite at the surface of carburized iron
Authors: Moszyński D. , Grabke H. J. , Schneider A. 
Published: October 2002

AbstractThe effect of sulphur on the formation of graphite at the surface of carburized iron and the decomposition of cementite were studied by Auger electron spectroscopy (AES). Graphite growth was observed on the iron surface covered with various amounts of sulphur. On the surface with a sulphur coverage of ∼40% a graphite layer was already formed at 400°C. Sulphur islands present on the surface were not influenced by the growing graphite. If the iron surface was saturated with sulphur, graphite growth started only at temperatures of >550°C. In this case, a graphite layer was formed on top of the adsorbed sulphur atoms. The nucleation sites for graphite formation may be grain boundaries, phase boundaries and other crystal defects or vacancies in the sulphur layer.The decomposition of cementite on the sample surface was also studied following the increase of the graphite peak. Coverage of the surface with sulphur led to a substantial decrease of the decomposition rate of cementite. A linear decrease of the rate of cementite decomposition with increasing sulphur concentration on the surface was found. When the cementite surface was saturated with sulphur, the formation of graphite was almost stopped, but even then a slow graphite growth could be observed. Copyright © 2002 John Wiley & Sons, Ltd.