bluuebunny/crossref_metadata_2025_split huggingface dataset:
Novel natural ligands for Drosophila olfactory receptor neurones
Authors: Stensmyr Marcus C. , Giordano Elena , Balloi Annalisa , Angioy Anna-Maria , Hansson Bill S. 
Published: January 2003

SUMMARY
Due to its well-defined genome, the fruitfly Drosophila melanogaster has become a very important model organism in olfactory research. Despite all the research invested, few natural odour ligands have been identified. By using a combined gas chromatographic—single receptor neurone recording technique (GC—SC), we set out to identify active odour molecules in head space-collected volatiles from preferred food sources, i.e. different overripe or rotting fruit. In total, we performed 101 GC—SC experiments on 85 contacted sensilla. Using GC—mass spectrometry, we identified 24 active compounds. Synthetic samples of these compounds were used to establish dose—response curves for several of the receptor neurone types encountered. The response patterns of individual neurones were repeatable, and neurones were found to reside in stereotyped pairs. In total,we identified eight distinct sensillum types based on response profiles of 12 olfactory receptor neurone types. In most recordings, a single GC peak would produce a strong response, whereas a few other, often chemically related,compounds would produce weaker responses. The GC—SC recordings revealed that the olfactory receptor neurones investigated were often selective and could be divided into distinct functional types with discrete characteristics. Dose—response investigations revealed very low response thresholds to the tested compounds. Six of the novel ligands were also tested for their behavioural effect in a T-maze set up. Of these, five elicited attraction and one elicited repulsion.
Cracking under fretting fatigue: Damage prediction under multiaxial fatigue
Authors: Dubourg M-C , Berthier Y , Vincent L 
Published: January 2003

Fretting is one of the plagues of modern industry. It occurs whenever a junction between components is subjected to cyclic sliding, with small relative displacements at the interface of the contacting surfaces. Further cyclic bulk stresses may be superimposed on to one or both components. The investigation of fretting wear and fretting fatigue started in the early 1970s. It is responsible for premature fatigue failures and often limits the life of a component. Crack initiation and growth under fretting contact conditions have been investigated. The fretting map concepts allow the first degradation responses of the material—no degradation, cracking and wear—to be related to a fretting regime with its corresponding local contact conditions during fretting tests. The fretting fatigue prediction models have been developed and compared to experiments conducted either on metallic or photoelastic materials. A special emphasis has been directed towards crack nucleation and early growth during stage I, the stage I-stage II transition and stage II crack growth (crack initiation sites, orientation, growth path, formation of a branch, growth mechanism). The analysis of the different stages that comprise the crack lifetime has been carried out in order to understand the effects of diverse parameters that are thought to influence the fretting damage.
Riveted single lap joints Part 2: Fatigue life prediction
Authors: Fung C-P , Smart J 
Published: January 2003

Fatigue lives of snap and countersunk riveted single lap joints with either one-row or two- rows of rivets have been predicted with fatigue laws using either local total strain range or effective stress obtained from finite element analyses and data obtained from fatigue testing of plates with holes. The finite element models of the joints were subjected to an alternating cyclic load; plasticity and nonlinear geometry are considered. The failures have also been metallurgically examined and gave evidence of fretting damage. It was found that all the data points lie within a narrow band using the strain-life law although the band is wider when using the effective stress-life law, but it is impossible to predict the fatigue life from one kind of specimen to another using the conventional stress-life law.
Catalytic and Stereoselective Glycosylation with Disarmed Glycosyl Fluoride by Using a Combination of Stannous(II) Chloride (SnCl2) and Silver Tetrakis(pentafluorophenyl)borate [AgB(C6F5)4] as a Catalyst
Authors: Mukaiyama Teruaki , Maeshima Hisashi , Jona Hideki 
Published: January 2003

Abstract
A catalytic and stereoselective glycosylation of various glycosyl acceptors with disarmed glycosyl fluorides is successfully carried out by using a combination of stannous(II) chloride (SnCl2) and silver tetrakis(pentafluorophenyl)borate [AgB(C6F5)4] as a catalyst in the coexistence of MS5A in toluene and the corresponding 1,2-trans di- or trisaccharides were obtained in high yields.
Hydrogen-Bonded Lyotropic Liquid Crystals of Folic Acids: Responses to Environment by Exhibiting Different Complex Patterns
Authors: Kanie Kiyoshi , Yasuda Takayasu , Nishii Masayuki , Ujiie Seiji , Kato Takashi 
Published: January 2003

Abstract
Lipophilic folic acid derivatives exhibit lyotropic liquid-crystalline states in organic solvents. The change of the mesophases from lamellar to columnar is induced by the change of specific hydrogen bonding patterns from ribbon to disk with the increase of hydrophobic environment.
Novel Preparation of Vanadyl Pyrophosphate for Selective Oxidation of n-Butane Utilizing Intercalation and Exfoliation
Authors: Hiyoshi Norihito , Yamamoto Naoki , Okuhara Toshio 
Published: January 2003

Abstract
Intercalation–exfoliation of VOPO4·2H2O crystallites (20 µm in size) in 2-butanol, followed by reduction with 2-butanol, brought about thin layers of precursor, VOHPO4·0.5H2O, with size of about 2 µm. The obtained vanadyl pyrophosphate (27 m2 g−1) and the corresponding SiO2 composite were highly active and selective for selective oxidation of n-butane.
Ionic Conductivity and NMR Self-Diffusion in Poly(macromonomer)s of Vinylbenzyl Poly(ethylene oxide)s
Authors: Tsukahara Yasuhisa , Hashimoto Kazuhiko , Kaeriyama Kyoji , Niwa Arei , Mehta Mary Anne , Fujinami Tatsuo , Hayamizu Kikuko 
Published: January 2003

Abstract
Ionic conductivity and NMR self-diffusion in the complex of poly(macromonomer)s of VB–PEO doped with the lithium salt Li(CF3SO2)2N were investigated. Ionic conductivity was enhanced by the multibranched structure of the poly(macromonomer). The NMR spin–lattice relaxation times showed that the hopping motion of the Li ions were correlated with PEO chain motion. NMR self-diffusion data showed evidence of the multi-site diffusion of anions in the complex at near room temperature.
Sensitivity analysis of the climate of a chaotic ocean circulation model
Authors: Lea Daniel J. , Haine Thomas W. N. , Allen Myles R. , Hansen James A. 
Published: January 2003

AbstractWe explore sensitivity analyses of ocean circulation models by comparing the adjoint and direct‐perturbation methods. We study the sensitivity of time‐averaged inter‐gyre vorticity transport to the imposed wind‐stress curl in an eddy‐permitting reduced‐gravity ocean model of a double gyre. Two regimes exist: a non‐chaotic regime for low wind‐stress curl, and a chaotic regime for stronger wind forcing. Direct‐perturbation methods are found to converge, with increasing integration time, to a stable ‘climate’ sensitivity in both the chaotic and non‐chaotic regimes. The adjoint method converges in the non‐chaotic regime but diverges in the chaotic regime. The divergence of adjoint sensitivity in the chaotic regime is directly related to the chaotic divergence of solution trajectories through phase‐space. Thus, standard adjoint sensitivity methods cannot be used to estimate climate sensitivity in chaotic ocean circulation models. An alternative method using an ensemble of adjoint calculations is explored. This is found to give estimates of the climate sensitivity of the time‐mean vorticity transport with O(25%) error or less for integration times ranging from one month to one year. The ensemble‐adjoint method is particularly useful when one wishes to produce a map of sensitivities (for example, the sensitivity of the advective vorticity transport to wind stress at every point in the domain) as direct sensitivity calculations for each point in the map are avoided. However, an ensemble‐adjoint of the variance of the vorticity transport to wind‐stress curl fails to estimate the climate sensitivity. We conclude that the most reliable method of determining the climate sensitivity is the direct‐perturbation method, but ensemble‐adjoint techniques may be of use in some problems. Copyright © 2002 Royal Meteorological Society.
Preliminary studies on the variational assimilation of cloud–radiation observations
Authors: Janiskov'a Marta , Mahfouf Jean‐françOis , Morcrette Jean‐jacques 
Published: January 2003

AbstractA linearized cloud scheme and a radiation scheme including cloud effects have been developed at the ECMWF to assimilate cloud properties in the framework of the 4D‐Var system. To investigate the potential of those schemes to modify the model temperature, humidity and cloud profiles to produce a better match to the observed radiation fluxes, 1D‐Var experiments have been carried out first with simulated observations and then using data from the Atmospheric Radiation Measurement programme. The assimilation experiments with simulated observations show that it is possible to reduce or increase the cloud cover when using the 1D‐Var approach to improve the fit of the model to the observed radiative fluxes. However, there is also a potential danger of adjusting the model state to the observed fluxes with resulting temperature and humidity profiles very different from the true ones. The assimilation of real observations demonstrates the capability of 1D‐Var to improve the analysis of temperature and specific humidity. Some weaknesses have also been identified, such as the problem of triggering clouds and the need, in some situations, for other observations to complement the surface ones. Copyright © 2002 Royal Meteorological Society.
Analysis of the numerics of physics–dynamics coupling
Authors: Staniforth Andrew , Wood Nigel , Côté Jean 
Published: January 2003

AbstractA methodology for analysing the numerical properties of schemes for coupling physics parametrizations to a dynamical core is presented. As an example of its application, the methodology is used to study four coupling schemes (‘explicit’, ‘implicit’, ‘split‐implicit’ and ‘symmetrized split‐implicit’) in the context of a semi‐implicit semi‐Lagrangian dynamical core. Each coupling scheme is assessed in terms of its numerical stability and of the accuracy of both its transient and steady‐state responses. Additionally, the occurrence of spurious, computational resonance is analysed and discussed. It is found that in this respect all four schemes behave similarly. In particular, in the absence of any damping mechanism to control resonance, the time‐step restriction needed to avoid spurious resonance is twice as restrictive for time‐dependent forcing as for stationary forcing. © Crown Copyright, 2002.
Characterization of acrylamide polymers for enhanced oil recovery
Authors: Sabhapondit Anupom , Borthakur Arun , Haque Inamul 
Published: January 2003

AbstractFour different copolymers, of acrylamide and acrylic acid, acrylamide and 2‐acrylamido‐2‐methyl propane sulfonic acid, N,N‐dimethylacrylamide and acrylic acid, and N,N‐dimethylacrylamide and 2‐acrylamido‐2‐methyl propane sulfonic acid (sodium salts), were prepared. The copolymers were characterized by their intrinsic viscosities and monomer ratios and with IR, 1H‐NMR, and X‐ray diffraction (XRD) spectroscopy. No crystallinity was observed by differential thermal analysis, and this was well supported by XRD. All the polymers showed low decomposition temperatures. A number of decomposition temperatures were observed in differential thermogravimetry thermograms because of the elimination of gases such as CO2, SO2, CO, and NH3. The replacement of the acrylate group with a sulfonate group produced polymers that were more compatible with brine, whereas the replacement of acrylamide with a more hydrophobic group such as N,N‐dimethylacrylamide produced a more shear‐resistant polymer. A N,N‐dimethylacrylamide‐co‐sodium‐2‐acrylamido‐2‐methyl propane sulfonate copolymer was better with respect to thermal stability when the polymer solution was aged at 120°C for a period of 1 month. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1869–1878, 2003
Styrene miniemulsion polymerization stabilized by carboxylated polyurethane. I. Stability and polymerization
Authors: Yu Zhang‐Qing , Lee Doug‐Youn , Cheong In‐Woo , Shin Jin‐Sup , Park Young‐Jun , Kim Jung Hyun 
Published: January 2003

AbstractStability of the styrene miniemulsion costabilized by carboxylated polyurethane resins was investigated. The shelf life and the droplet size were measured. The results show that styrene miniemulsion costabilized by carboxylated polyurethane can be prepared although it is not as efficient as is hexadecane. The shelf life of the miniemulsion is influenced by the amount of the polyurethane and sodium dodecyl sulfate. The alkaline condition and the smaller molecular weight of the polyurethane are in favor of the stability of the miniemulsion. The polymerization results show that the hydrophility of the particle or droplet surface plays an important role in the process of the nucleation and polymerization. Homogeneous nucleation and droplet nucleation coexist in these systems. Nucleation lasts to 40–60% conversion of the monomer in the acid medium, but it continues until the end of the polymerization in the alkaline medium. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1933–1940, 2003
Styrene miniemulsion polymerization stabilized by carboxylated polyurethane. II. Kinetics
Authors: Yu Zhang‐Qing , Lee Doug‐Youn , Cheong In‐Woo , Shin Jin‐Sup , Park Young‐Jun , Kim Jung‐Hyun 
Published: January 2003

AbstractA styrene miniemulsion was prepared using carboxylated polyurethane as the sole costabilizer and sodium dodecyl sulfate as the surfactant. The effects of the amount of carboxylated polyurethane, the amount of the initiator and surfactant, the presence of a water‐phase inhibitor (sodium nitrite), and the reaction temperature on the kinetics of the miniemulsion polymerization were investigated. The evolution of the particle size during the polymerization was measured. The results show that the polymerization rate was proportional to the 0.21 power of the surfactant concentration and the 0.30 power of azobisisobutyronitrile. The droplet nucleation and homogeneous nucleation were found to be coexistent in the polymerization. The hydrophility of the particle surface plays a key role in the nucleation of the particle and, therefore, has an important effect on the kinetics of the polymerization. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1941–1947, 2003
Peroxydiphosphate–metal ion–cellulose thiocarbonate redox system‐induced graft copolymerization of vinyl monomers onto cotton fabric
Authors: Zahran M. K. , Mahmoud R. I. 
Published: January 2003

AbstractThe grafting of methacrylic acid (MAA) and other vinyl monomers onto cotton cellulose in fabric form was investigated in an aqueous medium with a potassium peroxydiphosphate–metal ion–cellulose thiocarbonate redox initiation system. The graft copolymerization reaction was influenced by peroxydiphosphate (PP) concentration, the pH of the reaction medium, monomer concentration, the duration and temperature of polymerization, the nature of vinyl monomers, and the nature and concentration of metallic ions (activators). On the basis of a detailed investigation of these factors, the optimal conditions for the grafting of MAA onto cotton fabric with the said redox system were as follows: [Fe2+] = 0.1 mmol/L, [PP] = 2 mmol/L, [MAA] = 4%, pH‐2, grafting time = 2 h, grafting temperature = 70°C, and material/liquor ratio = 1 : 50. Under these optimal conditions, the graft yields of different monomers were in the following sequence: MAA ≫ acrylonitrile > acrylic acid > methyl acrylate > methyl methacrylate. The unmodified cellulosic fabric (the control) had no ability to be grafted with MAA with the PP–Fe2+redox system. The percentage of grafting onto the thiocarbonated cellulosic fabric was more greatly enhanced in the presence of iron salts than in their absence. This held true when the lowest concentrations of these salts were used separately. A suitable mechanism for the grafting processes is suggested, in accordance with the experimental results. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1879–1889, 2003
Effect of diluents on the decomposition behavior of vinyl ester resin
Authors: Agrawal S. , Mishra A. , Rai J.S.P. 
Published: January 2003

AbstractAn acidic vinyl ester resin (∼6 mg KOH per gram of solid) was prepared by reacting a bisphenol‐A‐based epoxy resin with acrylic acid in the presence of tributylamine. The acrylated epoxy resin thus obtained was characterized by Fourier transform infrared spectroscopy. Five samples of vinyl ester resin containing styrene and methyl methacrylate (MMA) in the weight ratios 40:0, 30:10, 20:20, 10:30, and 0:40 were prepared at 30°C. These samples were cured, using 2 phr benzoyl peroxide, at 90 ± 2 °C for 1 h. The decomposition behavior of all the samples was studied by thermogravimetric analysis (TGA) at 10°C min−1. The TG and dynamic thermogravimetry (DTG) thermograms showed single‐step degradation in the individual cases of styrene and MMA, whereas a two‐step degradation process was observed when styrene was mixed with MMA in any proportion. For all the samples, the order of the reaction was one for the first step. This value was calculated with the Coats and Redfern equation in accordance with the best‐fit analysis and further confirmed by linear regression analysis. From this value of reaction order (n), the activation energy (E) and pre‐exponential factor (Z) were calculated, and the validity of the data was checked by statistical analysis. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1952–1956, 2003
Mechanical properties of polyethylene mixtures crystallized under high pressure
Authors: Nakafuku Chitoshi , Nishimura Keiko 
Published: January 2003

AbstractThe mechanical properties of a medium molecular weight polyethylene (MMW‐PE) and an ultrahigh molecular weight PE (UHMW‐PE) binary mixture with different weight fractions crystallized from the melt at 0.1 and 450 MPa were studied. The tensile modulus, yield stress, and strain were obtained as a function of the weight fractions in the PE mixtures at 25 and 85°C. The tensile modulus in the sample crystallized at 0.1 MPa decreased from 1.5 GPa of pure MMW‐PE to about 0.4 GPa of pure UHMW‐PE with the UHMW‐PE content but it did not decrease with the UHMW‐PE in the sample crystallized at 450 MPa in testing at 25°C. A decreasing rate of the storage modulus E′ of UHMW‐PE in a dynamic measurement for the sample crystallized at 0.1 MPa with the temperature is larger than that of the sample crystallized at 450 MPa. These experimental facts are interpreted in relation to the molecular motion and crystallinity of the sample. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1962–1968, 2003
Characterization of coil coatings by thermal analysis
Authors: Korhonen M. , Starck P. , Löfgren B. 
Published: January 2003

AbstractThe interrelationship between the network formation process and performance properties makes cure process studies critically important in the coil‐coating industry. The objective of this work was to introduce thermal analysis into the evaluation of curing of uncured samples and in studies of the glass‐transition temperatures of cured samples. Thermal analysis, dynamic mechanical analysis (DMA), and differential scanning calorimetry (DSC) were used to characterize gelation and curing of three types of samples: paints, coated sheets, and free films. In addition to the generally used three‐point‐bending and extension geometries, a cup‐and‐plate geometry also was used in analyzing gelation and curing of liquid samples. These thermal analyses are suited to the purpose of characterizing coil coatings. A correlation between PMT (peak metal temperature) and measured Tg (glass‐transition temperature) was found, as well as effectively distinguishing different curing conditions. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 2016–2022, 2003
Nanostructure of EVA/organoclay nanocomposites: Effects of kinds of organoclays and grafting of maleic anhydride onto EVA
Authors: Li Xiucuo , Ha Chang‐Sik 
Published: January 2003

AbstractNanostructure of poly(ethylene‐co‐vinyl acetate)/organically modified montmorillonite (MMT; EVA/organoclay) nanocomposites prepared by melt intercalation process was investigated using X‐ray diffraction (XRD) and transmission electron microscopy (TEM). Three kinds of organoclays were used to see their influences on the nanostructure of the EVA hybrids. The effects of the polar interactions between the polymer and the silicate layers of organoclays were also investigated by grafting maleic anhydride onto EVA. It was found that the strong polar interactions between the polymer and the silicate layers of organoclays are critical to the formation of polymer‐layered silicate nanocomposites. The results also showed that increasing the mixing temperature was unfavorable to improve the dispersion of organoclays in the EVA matrix. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1901–1909, 2003
Ru(salen)‐catalyzed asymmetric sulfimidation and subsequent [2,3]sigmatropic rearrangement
Authors: Murakami Masakazu , Uchida Tatsuya , Saito Bunnai , Katsuki Tsutomu 
Published: January 2003

Abstract(OC)Ru(salen) 1 was found to catalyze sulfimidation of alkyl aryl sulfides in the presence of arylsulfonyl azide with high enantioselectivity, up to 99% ee. When the substrates were allylic sulfides, the resulting sulfimides underwent [2,3]sigmatropic rearrangement to give the corresponding N‐allyl toluenesulsulfonamides with greater than 80% ee. Chirality 15:116–123, 2003. © 2003 Wiley‐Liss, Inc.
Stereocontrolled synthesis of 1‐acetylen‐2,3‐di‐o‐benzyl‐tetrahydrofurans, 1,4‐anhydro‐arabinitol, and α,β‐dihydroxy‐γ‐alkyl‐butyrolactones
Authors: Díaz David D. , Ramírez Miguel A. , Ceñal J. Pedro , Saad J. Roberto , Tonn Carlos E. , Martín Victor S. 
Published: January 2003

AbstractThis article describes a concise and efficient synthesis of 1‐acetylen‐2,3‐di‐O‐benzyl‐tetrahydrofurans from tartaric acid esters using as the key step the stereocontrolled cyclization of Co2(CO)6‐complexed propargylic diols. This molecule led to enantiomerically pure 1,4‐anhydro‐arabinitol and α,β‐dihydroxy‐γ‐alkyl‐butyrolactones. In the latter case, the critical methylene oxidation at the oxygen vicinal position was performed by RuO4. Chirality 15:148–155, 2003. © 2003 Wiley‐Liss, Inc.
NetBuild: transparent cross‐platform access to computational software libraries
Authors: Moore Keith , Dongarra Jack 
Published: January 2003

AbstractNetBuild is a suite of tools which automate the process of selecting, locating, downloading, configuring, and installing computational software libraries from over the Internet, and which aid in the construction and cataloging of such libraries. Unlike many other tools, NetBuild is designed to work across a wide variety of computing platforms, and perform fine‐grained matching to find the most suitable version of a library for a given target platform. We describe the architecture of NetBuild and its initial implementation. Copyright © 2002 John Wiley & Sons, Ltd.