bluuebunny/crossref_metadata_2025_split huggingface dataset:
Coastal deformation between the Versilia and the Garigliano plains (Italy) since the last interglacial stage
Authors: Nisi Marco F. , Antonioli Fabrizio , Pra Giuseppe Dai , Leoni Gabriele , Silenzi Sergio 
Published: December 2003

AbstractThe opening of the north‐central Tyrrhenian Sea is the result of the Cretaceous–Paleogene alpine collision, which triggered a series of regional uplift, subsidence and transcurrent tectonic mechanisms along the coastal Tyrrhenian sectors of peninsular Italy. These tectonic processes, in conjunction with the effects of glacio‐ and hydro‐isostasy during the Quaternary, produced substantial crustal responses that, in some cases, reached metres in extent. In the study of coastal neotectonics, geomorphological markers of the last interglacial maximum, corresponding to marine isotope stage 5.5, are generally used to quantify the magnitude of the vertical crustal displacements that have occurred since 125 kyr. Through altimetrical, palaeoenvironmental and chronological reinterpretation of the most significant works published since 1913, combined with an additional set of data reported here, a detailed reconstruction of the shoreline displacements evident along 500 km of coast between northern Tuscany and southern Latium is presented. The reconstruction was carried out by quantifying the vertical movement since the last interglacial period and by identifying the tectonic behaviour of different coastal sectors. This has been done by carefully choosing the eustatic marker, among those available at each study site, in order to minimize the margin of error associated with the measurements. Copyright © 2003 John Wiley & Sons, Ltd.
Non‐linear intermolecular polarization and collision‐inducedν3Raman transition by gaseous CO2in mixture with argon
Authors: Rachet F. , Chrysos M. , Kouzov A. 
Published: December 2003

AbstractExperimental collision‐induced CO2–Ar wavenumber‐resolved depolarized absolute‐unit Raman differential scattering cross‐sections,I∥, were recorded for the first time for the ν3band of carbon dioxide. By means of a novel diagrammatic technique (briefly presented), we managed to calculate the irreducible parts (r= 0, 2) of the incremental collision‐induced polarizability tensor$\Delta \hat{\alpha}^{(r)}$and to interpret the zeroth‐ and second‐order spectral moments extracted from the experiment. As was borne out from our calculations,$\Delta \hat{\alpha}^{(r)}$contains a non‐linear term never considered in any of the previous studies. The effect is produced by the second‐order non‐linear polarization of one of the colliding partners, which is polarized by the incident electromagnetic field and by the CO2dipole field oscillating at the ν3frequency. Because of the large value of the ν3transition dipole moment, the impact of the new term was found to be crucial. Copyright © 2003 John Wiley & Sons, Ltd.
J‐aggregation visualized with two‐photon‐resonant third‐harmonic generation
Authors: Akimov D. A. , Ivanov A. A. , Alfimov M. V. , Grabchak E. P. , Shtykova A. A. , Petrov A. N. , Podshivalov A. A. , Zheltikov A. M. 
Published: December 2003

AbstractThird‐harmonic generation (THG) with a two‐photon‐absorption (TPA) type resonance was used to monitor the J‐aggregation of ethyl thiacarbocyanine in aqueous solution. Correlations between TPA‐resonant THG and two‐photon‐excited photoluminescence are revealed, indicating the significance of excited states for non‐linear‐optical processes in J‐aggregating solutions. Similar to Raman resonances in coherent anti‐Stokes Raman scattering, TPA resonances in THG allow THG enhancement to be effectively decoupled from the growth of radiation losses. Copyright © 2003 John Wiley & Sons, Ltd.
Determination of temperatures and fuel/air ratios in an ethene–air flame by dual‐pump CARS
Authors: Beyrau F. , Seeger T. , Malarski A. , Leipertz A. 
Published: December 2003

AbstractThe simultaneous determination of temperature and ethene, oxygen and nitrogen concentrations is demonstrated using the dual‐pump coherent anti‐Stokes Raman spectroscopy (CARS) technique. Temperature and relative N2/O2 concentrations were calculated from contour fitting against theoretically calculated spectra, while relative N2/C2H4 concentrations were obtained from the integrated intensity ratio, calibrated in a heated gas cell. Detailed measurements were performed in a partially premixed ethene–air co‐flowing jet flame established on a slot burner. As the two vibrational Raman modes ν2 (1623 cm−1) and ν3 (1342 cm−1) of ethene are in close vicinity of the oxygen Raman transition at 1556 cm−1, either the ν2 or the ν3 transition can be excited together with O2 using a single narrowband–broadband laser combination. Both possibilities are discussed. Additionally, nitrogen is probed for thermometry with the same broadband laser but another narrowband laser in a dual‐pump CARS approach. Copyright © 2003 John Wiley & Sons, Ltd.
Femtosecond time‐resolved two‐photon absorption resonant four‐wave mixing in three‐dimensional spiropyran–PMMA samples
Authors: Konorov S. O. , Sidorov‐Biryukov D. A. , Bugar I. , Chorvat D. , Chorvat D. , Zheltikov A. M. 
Published: December 2003

AbstractThe potential of four‐wave mixing with two‐photon absorption resonances for time‐resolved studies of ultrafast processes triggering photochromic transformations in three‐dimensional spiropyran–poly(methyl methacrylate) samples is demonstrated. Our experimental approach involves using 100 fs pulses of 800 nm fundamental radiation of a Ti:sapphire laser as a two‐photon absorption resonant pump and 130 fs frequency‐tunable pulses of an optical parametric amplifier as a time‐delayed probe. The use of two‐photon resonances allows strong one‐photon absorption, typical of conventional pump–probe experiments, to be avoided, giving access to any point inside a 3D photochromic sample. Copyright © 2003 John Wiley & Sons, Ltd.
Temperature measurement in gas mixtures by femtosecond Raman‐induced polarization spectroscopy
Authors: Tran H. , Lavorel B. , Faucher O. , Saint‐Loup R. , Joubert P. 
Published: December 2003

AbstractThe potential of femtosecond Raman‐induced polarization spectroscopy (RIPS) for the simultaneous determination of temperature and concentrations was investigated. These measurements were related to the rotational time response of the molecular gas mixture, which was measured as a function of the pump–probe time delay. The change of the polarizability anisotropy with respect to the vibrational levels was taken into account. The results of temperature measurements in pure CO2 showed good agreement with the values obtained by a thermocouple. The RIPS technique was also applied to a CO2–N2 gas mixture to determine simultaneously temperatures and concentrations at temperatures up to 600 K. The accuracy and the feasibility of the method applied to highest temperatures are discussed. Copyright © 2003 John Wiley & Sons, Ltd.
Rotational time‐domain CARS in H2: departure from statistically independent collisional dephasing model
Authors: Arakcheev V. G. , Jakovlev D. V. , Morozov V. B. , Olenin A. N. , Tunkin V. G. 
Published: December 2003

AbstractTime‐domain CARS was applied to study dephasing of H2 S0(0) and S0(1) rotational transitions in the density range from 0.004 to several amagat at 296 and 80 K. Dephasing of the S0(0) transition in pure H2 corresponds satisfactorily to the theoretical model of statistically independent collisional perturbations of translational and rotational molecular motions. Experimental dephasing curves of the S0(1) transition in pure H2 in the density region of the Dicke effect manifestation are steeper than the theoretical curves calculated on the basis of the statistically independent dephasing model. This departure is especially noticeable at liquid nitrogen temperature. At the same time, dephasing curves of the S0(1) transition in He as a buffer gas measured at room temperature demonstrate fairly good coincidence with the theoretical model. The departure of the experimental dephasing curves of the S0(1) transition in pure H2 from the statistically independent model can be mainly attributed to resonance collisions. Copyright © 2003 John Wiley & Sons, Ltd.
Density evolution of the picosecond time‐domain CARS responses from carbon dioxide gas
Authors: Morozov V. , Mochalov S. , Olenin A. , Tunkin V. , Kouzov A. 
Published: December 2003

AbstractResults of a joint experimental and theoretical study of CARS transients produced by picosecond two‐color pumping of the CO2 Q‐branch at 1285 cm−1 are reported. The coherence decay patterns recorded in a wide dynamic range (3–8 decades) and in a broad gas density interval (ρ = 0.02–20 amagat) made it possible to track different channels of collision‐induced relaxation. The undertaken signal simulations account for the finite pump–probe pulse durations and also for the collision‐perturbed Doppler effect, vibrational dephasing and collisional mixing of rotational states. The last effect was tackled by applying the quantum fast‐collision model of rotational relaxation. Our recent data on the other Fermi‐dyad component at 1388 cm−1 were also simulated in the same way to derive a set of optimized relaxation rate parameters. New features revealed at low densities are ascribed to interference between the velocity and rotational relaxation channels. Copyright © 2003 John Wiley & Sons, Ltd.
Temperature measurements in combustion—not only with CARS: a look back at one aspect of the European CARS Workshop
Authors: Stricker W. , Lückerath R. , Meier U. , Meier W. 
Published: December 2003

AbstractTemperature is perhaps the most important quantity in combustion research and technology. The potential and state of the art of various laser‐based diagnostics used for the determination of temperature in laboratory flames and practical combustion devices are discussed and illustrated with a few representative examples from our laboratory. The emphasis is on coherent anti‐Stokes Raman scattering (CARS), the main topic of the European CARS Workshop in the past. As a result, CARS is today the most matured and proven technique for technical applications. In addition to CARS, however, linear laser spectroscopic methods also deliver valuable and supplementary information on temperature in combustion. Copyright © 2003 John Wiley & Sons, Ltd.
Relationships between volatile production, fruit quality and sensory evaluation of Fuji apples stored in different atmospheres by means of multivariate analysis
Authors: Echeverría G , Fuentes MT , Graell J , López ML 
Published: December 2003

AbstractAroma compounds, quality parameters and sensory characteristics of Fuji apples were analysed after 3, 5 and 7 months of storage at 1 °C in normal air (AIR; 210 l m−3 O2/0.3 l m−3 CO2) and in controlled atmospheres with O2/CO2 ratios of 10 l m−3/10 l m−3 (ULO1), 10 l m−3/20 l m−3 (ULO2) and 30 l m−3/20 l m−3 (SCA). After storage the apples were kept at 20 °C for 1, 5 and 10 days. The components that contributed most to the characteristic aroma of Fuji apples were ethyl 2‐methylbutanoate, 2‐methylbutyl acetate and hexyl acetate. The highest aroma compound production was found in ULO1 fruits after 5 months of cold storage and 1 day of shelf‐life. After 3 and 5 months of storage, ULO1 fruits showed the highest firmness after both 1 day and 10 days at 20 °C. After 7 months of storage plus 1 day at 20 °C, ULO2 fruits showed higher titratable acidity and soluble solid content; fruit firmness was also maintained throughout the shelf‐life period. Generally, background and superficial colour were not influenced by storage conditions. A statistically significant correlation was found between aroma compounds, quality parameters and sensory evaluation. Copyright © 2003 Society of Chemical Industry
Selected functional properties of waxy corn and potato starches after illumination with linearly polarised visible light
Authors: Fiedorowicz Maciej , Chaczatrian Gohar 
Published: December 2003

AbstractAqueous suspensions (30%) of waxy corn and potato starches were illuminated for 5–50 h with linearly polarised visible light (λ > 500 nm). Molecular weights (M̄w) and radii of gyration (R̄g) of the amylopectin and amylose fractions of illuminated waxy corn starch, and the amylopectin, intermediate, and amylose fractions of illuminated potato starch were measured by high‐performance size exclusion chromatography coupled with multiangle laser light scattering and refractive index detection. The weight‐average molecular weight (M̄w) and radius of gyration (R̄g) of the amylopectin fraction of native waxy corn starch were 14.45 × 107 and 161.1 nm respectively. After 15 h of illumination a decrease in M̄w (5.80 × 107) and R̄g (117.6 nm) was observed. Illumination for 25 h, led to an increase in M̄w (7.60 × 107) and R̄g (134.0 nm). Further illumination, up to 50 h resulted in a slight decrease in M̄w (6.74 × 107). The molecular weight and radius of gyration of the amylopectin fraction of native potato starch were 21.30 × 107 and 207 nm respectively. Illumination for 15 h led to a decrease in M̄w (14.87 × 107) and R̄g (141.5 nm), followed by an increase in both values after 25 h (18.97 × 107, 146.6 nm) and 50 h (19.69 × 107, 207.1 nm) of illumination. Illumination influenced the swelling power, solubility, susceptibility to α‐amylolysis and X‐ray diffractogram of the starches. A varying increase in the solubility passed through a minimum after 25 h of illumination. The X‐ray diffraction pattern and susceptibility to enzymatic hydrolysis of waxy corn starch did not change, but in potato starch a gradual, illumination time‐dependent increase in the amylolysis rate took place. This effect could result from the reduction in crystallinity of the starch as indicated by the X‐ray diffraction pattern. Copyright © 2003 Society of Chemical Industry
Screening and distinction of coffee brews based on headspace solid phase microextraction/gas chromatography/principal component analysis
Authors: Rocha Sílvia , Maeztu Laura , Barros António , Cid Concepción , Coimbra Manuel A 
Published: December 2003

AbstractThe volatile profiles of espresso and plunger (cafetière) coffees prepared from (1) an 80:20 (w/w) blend of natural roasted Robusta and Arabica (Robusta Natural blend), (2) a 40:40:20 (w/w/w) blend of Robusta Natural blend, Robusta torrefacto roast (850 g kg−1 Robusta, 150 g kg−1 sugar) and (3) natural roasted pure Arabica were established by headspace solid phase microextraction (SPME) after selection of the fibre coating (polyacrylate or polydimethylsiloxane) and the temperature and time of extraction. For the analysis of furans and indoles the polyacrylate coating proved to be more suitable; however, for the overall characterisation of the volatile composition of espresso and plunger coffees the polydimethylsiloxane coating was chosen. SPME/gas chromatography (GC)/mass spectrometry (MS) analyses allowed the identification of 37 compounds: four aldehydes, two ketones, 11 furans, 10 pyrazines, two pyridines, three phenolic compounds, two indoles, one lactone, one ester and one benzothiazine. The volatile composition was related more to the botanical variety (Arabica or Robusta) than to the method of preparation of the brew (espresso or plunger). Furthermore, use of the variability provided solely by the GC peak areas and respective retention times, combined with principal component analysis (PCA), yielded the information necessary for discrimination. The combined technique of headspace SPME/GC/PCA, as an alternative to conventional techniques based on GC/MS, is proposed as a lower‐cost, fast and reliable technique for the screening and distinction of coffee brews. Copyright © 2003 Society of Chemical Industry
Synthesis and Solid State Properties of Novel Fluorescent Polyester Star Polymers
Authors: Klok Harm‐Anton , Becker Stefan , Schuch Falk , Pakula Tadeusz , Müllen Klaus 
Published: December 2003

AbstractTwo novel tetra‐ and hexahydroxy functionalized perylene chromophores have been used as initiators for the Sn(oct)2 catalyzed ring‐opening polymerization of different lactones. The arms of the resulting star polymers were comprised of either crystallizable poly(L‐lactide) or poly(ε‐caprolactone) arms or of amorphous poly[γ‐(tert‐amyl)‐ε‐caprolactone] chains. The star polymers were investigated by differential scanning calorimetry, X‐ray scattering and dynamic mechanical and optical spectroscopy. Whereas the thermal properties of the poly(ε‐caprolactone) stars were barely affected by the star topology, crystallization of the poly(L‐lactide) stars was strongly hindered by the star‐shaped architecture. Interestingly, for the amorphous poly[γ‐(tert‐amyl)‐ε‐caprolactone] stars a decrease in Tg with increasing chain length was found, reflecting the declining influence of the rigid perylene core on segmental mobility with increasing arm length. While the solid state and solution optical properties of high molar mass polyester stars were identical, the excitation and fluorescence emission spectra of spin‐coated films of the low molecular weight polymers revealed a red shift, pointing towards perylene – perylene interactions in these samples. The optical spectroscopy experiments suggested that arm length, rather than the number of arms, is the most important parameter determining encapsulation and preventing aggregation of the perylene core moieties in the solid state.magnified image
Hydrophilic Poly(ether‐ester)s and Poly(ether‐ester‐amide)s Derived from Poly(ε‐caprolactone) and COCl Terminated PEG Macromers
Authors: Crisci Leonilda , Volpe Claudio Della , Maglio Giovanni , Nese Giuseppe , Palumbo Rosario , Rachiero Giovanni P. , Vignola Maria C. 
Published: December 2003

AbstractA series of poly(ε‐caprolactone) (PCL)‐based multiblock poly(ether‐ester)s (PEE)s and poly(ether‐ester‐amide)s (PEEA)s were obtained from α,ω‐dihydroxy‐PCL ($\overline M _{\rm n}$ = 2–4 kDa) and COCl di‐terminated poly(ethylene oxide) (PEO) macromers (MAC) of different length ($\overline M _{\rm n}$ = 150, 300, 600, 1 000 Da). 4,7,10‐Trioxa‐1,13‐tridecanediamine was used in the synthesis of PEEAs. Bulk polycondensation processes were accomplished by one step (PEE) and two step (PEEA) procedures. PEEAs with PCL/MAC/Trioxy molar ratios 1:2:1 and 1:3:2 were investigated. The multiblock copolymer architecture was proved by 1H NMR and size exclusion chromatography (SEC) techniques. Unimodal molecular weight (MW) distributions and $\overline M _{\rm n}$ values in the range of 13.3–21.0 kDa (PEE) and 8.1–12.8 kDa (PEEA) were found. Crystalline PCL‐type phases were identified for both PEEAs and PEEs by X‐ray diffraction. The thermal transitions were investigated by differential scanning calorimetry (DSC). The Tm values (49.9–53.4 °C) reflect those of the PCL component while the Tg of PEEAs (−45 to −52 °C) are higher than those of the PEEs (−58 to −61 °C) or the macromers. The equilibrium water uptakes range from 1.0 to 18.4 wt.‐% (PEE) and from 4.4 to 8.8 wt.‐% (PEEA) depending on both the composition and length of the ethylene oxide sequences. A dependence of surface homogeneity on copolymer composition was found for PEEs by dynamic contact angle measurements.The preparation of PEEAs and PEEs.magnified imageThe preparation of PEEAs and PEEs.
Laccase‐catalyzed Synthesis and Antioxidant Property of Poly(catechin)
Authors: Kurisawa Motoichi , Chung Joo Eun , Uyama Hiroshi , Kobayashi Shiro 
Published: December 2003

AbstractCatechin was oxidatively polymerized by laccase in a mixture of a polar organic solvent and buffer to give a new class of flavonoid polymers. Myceliophthora laccase showed high catalytic activity for the polymerization. Using a mixed solvent of acetone and pH 5 acetate buffer efficiently produced the polymer. Under the selected conditions, DMF‐soluble polymers were obtained in good yields. Effects of reaction parameters on the yield, solubility, and molecular weight of the polymer have been systematically investigated. A radical species was detected in the polymer by ESR spectroscopy. The polymers showed greatly amplified superoxide scavenging activity and xanthine oxidase inhibitory activity compared with monomeric catechin.Superoxide scavenging activity of poly(catechin)s, n = 3. ○: catechin, □: poly(catechin).magnified imageSuperoxide scavenging activity of poly(catechin)s, n = 3. ○: catechin, □: poly(catechin).
Synthesis and Characterization of β‐Cyclodextrin Based Functional Monomers and its Copolymers with N‐isopropylacrylamide
Authors: Liu Yu‐Yang , Fan Xiao‐Dong , Gao Lei 
Published: December 2003

AbstractTwo novel monovinyl β‐cyclodextrin (β‐CD) monomers are synthesized. Their chemical compositions are characterized by means of element analysis, NMR and FT‐IR spectroscopy. The results show that the synthesis techniques used are convenient and efficient. Using N‐isopropylacrylamide as a comonomer, two novel linear copolymers can also be synthesized.Synthesis route of monovinyl β‐CD monomers.magnified imageSynthesis route of monovinyl β‐CD monomers.
2‐[(1‐Imidazolyl)formyloxy]ethyl Methacrylate as Selective Methacryloylating Agent: Kinetics of Reaction with Model Alcohols and Amines
Authors: Ranucci Elisabetta , Grigolini Michela , Ferruti Paolo 
Published: December 2003

AbstractThe kinetics of the coupling reactions of 2‐[(1‐imidazolyl)formyloxy]ethyl methacrylate (HEMA‐Im) with model primary and secondary alcohols and amines have been investigated both in the absence and in the presence of imidazole and triethylamine as catalysts. In the absence of added catalysts, alcohols either reacted very sluggishly or did not react at all with HEMA‐Im, but amines reacted completely in relatively short times. In the presence of catalysts, both primary and secondary alcohols underwent coupling reactions with HEMA‐Im, the former about ten times faster than the latter. Imidazole was a more effective catalyst than triethylamine. HEMA‐Im's ability to discriminate between amino and hydroxyl groups was tested with 4‐amino‐1‐butanol: the 1H NMR analysis of the reaction product confirmed 100% selectivity towards the amino group. It was therefore concluded that HEMA‐Im is a highly selective methacryloylating agent, with a synthetic potential for preparing multifunctional monomers and polymers.Reaction curves for HEMA‐Im with EtOH and PriOH at 37 °C in the presence of imidazole (HEM5 and HEM6) and triethylamine (HEM7 and HEM8).magnified imageReaction curves for HEMA‐Im with EtOH and PriOH at 37 °C in the presence of imidazole (HEM5 and HEM6) and triethylamine (HEM7 and HEM8).
Linear Terpyridine‐Ruthenium(II) Poly(ethylene glycol) Coordination Polymers
Authors: Hofmeier Harald , Schmatloch Stefan , Wouters Daan , Schubert Ulrich S. 
Published: December 2003

AbstractIn the present contribution, we synthesized linear coordination polymers based on oligo(ethylene glycol)s as well as poly(ethylene glycol)s and terpyridine ruthenium(II) complexes. The reaction conditions, e.g., solvent, concentration, were varied to obtain well‐soluble, high molecular weight polymers. The resulting compounds were characterized by UV‐vis and NMR spectroscopy. The viscosity of the materials was also investigated with and without salt addition. Finally, the polymers were characterized with DSC and AFM. AFM revealed a lamellar morphology.
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Synthesis and Dielectric Study of New Liquid‐crystalline Polysiloxanes Presenting a Thioether Spacer
Authors: Gilles Paul‐Philippe , Milano Jean‐Claude , Vernet Jean‐Louis 
Published: December 2003

AbstractThree new cyanobiphenyl polysiloxanes presenting long thioether spacers have been carried out. This type of spacer leads to very stable liquid‐crystalline polymers at room temperature and remove the crystallinity phenomenon. Dielectric analysis results show that the thioether spacer brings much more molecular flexibility to the system.Example of an “interdigitated” structure observed by X‐ray analysis.magnified imageExample of an “interdigitated” structure observed by X‐ray analysis.