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Highlights: [•] Black glaze ceramics from Pompeii were studied using several analytical techniques. [•] XRF and XRD were used to determine the chemical and mineralogical bulk composition. [•] SEM/EDS and Raman microscopy were used to characterize the black glazes. [•] Technological changes are suggested in the pottery production over the 4th–1st centuries BC. [ABSTRACT FROM AUTHOR]

Abstract: Raman microscopy has been used to identify the pigments decorating three valuable items owned by the Worshipful Company of Barbers (established in 1308 in London), one being a large leather screen dating to before 1712, the other two being illuminated title pages of books of ordinances of the Company dating to 1605 and 1658. Pigments which could not be fully characterised by this technique (particularly the green paints) have also been subject to XRF or SEM–EDX analysis. The combined analytical approach has shown that the pigments identified on all three items are typical of those in use as artists’ pigments in the 17th C and include azurite, indigo, vermilion, red lead, pink and yellow lakes, verdigris, lead white, calcite (and chalk), gypsum, carbon-based black, and gold and silver leaf. However in the case of the screen alone, restoration in the 1980s has been carried out with different pigments – haematite, phthalocyanine green, rutile, and a mixture of azurite, malachite and barium sulfate. This work constitutes the first in-depth study of painted leatherwork and demonstrates that the palette used for this purpose is similar to that used on other works of art of the same date. It has also allowed the original colour schemes of the decorations to be determined where pigment degradation has occurred. The combined analysis has also provided a more complete understanding of the materials used for, or on, objects to which access is limited. [Copyright &y& Elsevier]

Abstract: Scanning electron microscopy/energy dispersive X-ray analysis has earlier shown that the white background layer (slip) on painted pottery sherds (Yangshao culture, Henan, China, 4200 BC) is composed of kaolinitic clay containing titanium in the assumed form of TiO2 at just 1wt%. The same samples of white slip have now been studied by Raman microscopy, revealing bands characteristic of anatase, but none from the majority species, the matrix of kaolinitic clay. These results highlight the extraordinarily intense Raman scattering from even trace amounts of anatase and thus the need to recognise that, although the colours of archaeological artefacts are almost always determined by the nature of the matrix, the Raman spectrum may be determined by a highly scattering trace component such as anatase. The significance of anatase as a potential date-marker pigment on works of art and archaeological artefacts is discussed. [Copyright &y& Elsevier]

Abstract: The purpose of this study was to investigate the combined effect of the incorporation of vegetable products in diet and temperature on enzymatic pathways for high unsaturated fatty acids (HUFA) desaturation in sea bass larvae. Four replicated groups were fed a low (LH; 0.8% EPA+DHA) or a high (HH; 2.2% EPA+DHA) n-3 HUFA microparticulated diet from mouth opening, six days post-hatching and were reared at 16 or 22 °C. The four experimental conditions (LH16, HH16, LH22 and HH22) were tested for 45 days. At the end of the experiment, body weight, total length and biomass were affected by temperature (P <0.001), while biomass as well as fresh body weight was also influenced by diet (P <0.05 and P <0.001 respectively). This always lead to the same ranking of experimental conditions: HH22>LH22>HH16>LH16. The larval skeletal development was more advanced in 22 °C-groups than in 16 °C-ones (P <0.001), while it was not affected by diet. Amylase and trypsin pancreatic secretions did not vary between d-25 and d-45, indicating that pancreatic maturation was achieved at d-25. Low temperature combined with low dietary HUFA delayed intestinal maturation (P <0.001), while low temperature combined with high HUFA diet allowed larvae compensating for the initial intestinal maturation retardation. Lipase gene expression was down-regulated in HH16 group at d-25 (P <0.05) and in the two 16 °C-groups at d-45 (P <0.001), while lipase enzymatic activity was similar in all groups. This suggested the presence of a post-transcriptional regulation of this gene. PPAR α and PPAR β were not affected neither by temperature, nor by diet, suggesting that lipid metabolism was not significantly affected by a lowering in dietary n-3 HUFA when isolipidic diets were used. A higher DHA content was found in larvae than in their diets (×2 for LH; ×1.5 for HH) but the DHA content in PL of d-45 LH larvae was lower than the initial one, which revealed a HUFA deficiency in this group. Delta 6-desaturase (Δ6D) gene expression was significantly up-regulated by HUFA deprived diet (P <0.05) whatever the temperature was. This was supported by the increase in 18:3n-6 in LH larvae (P <0.001), which indicated a desaturation from 18:2n-6 by the Δ6D. This study clearly showed that larvae were able to adapt to an n-3 deprived diet by a stimulation of enzymatic pathways for HUFA desaturation, and that this adaptation was not affected by temperature. [Copyright &y& Elsevier]

Abstract: The enormous strides that have been made at the Arts/Science interface by the meticulous application of Raman microscopy to the study of artwork and archaeological artefacts are outlined. Important recent case studies are presented to illustrate the power of the technique to answer key questions of great art historical, conservational, cultural, restorational, archaeological and scientific interest. [Copyright &y& Elsevier]

Abstract: Six ninth-century stucco fragments from Samarra, Iraq, and now part of the Victoria and Albert Museum collections, were analysed non-destructively and in situ in the Museum by Raman microscopy in order to determine the identities of the pigments thereon. Carbon black, haematite, gypsum, indigo, lazurite, lead white, orpiment, pararealgar, red lead, vermilion and the As4S4 χ-phase were detected. The detection of several arsenic-containing pigments (orpiment, pararealgar and the As4S4 χ-phase), known to be poisonous and carcinogenic, has prompted strict health and safety protocols to be used when the objects are handled by museum staff or displayed in the galleries. This scientific study is the first to be carried out on any of the Samarra finds. [Copyright &y& Elsevier]

Abstract: A quantitative approach is presented to evaluate fatty acid incorporation in fish. Fatty acid composition of European sea bass juvenile was studied during an experiment using 6 isoproteic (54%) and isolipidic (18%) diets containing 0.23, 0.56, 0.72, 0.86, 1.01 and 1.86% DM n-3 highly unsaturated fatty acids (n-3 HUFA). Whole body fatty acid compositions were studied at the beginning and after 52 and 81 days feeding, fatty acid profiles evolved during time under dietary influences. Incorporations of individual fatty acids into total lipids were calculated as increases in individual fatty acids as percentages of the increase in total fatty acids during growth, on a per animal basis. Relative incorporations (RI) so defined generated similar profiles for the two periods for each dietary treatment, consistent with fatty acids being incorporated in a stable way during the experiment. For most fatty acids, linear regressions could be drawn between RIs in whole fish and % of fatty acids in dietary lipid. RIs for DHA, EPA and AA demonstrated these HUFAs were incorporated in the fish in lower proportion that diet contents, in this experiment. Fractional retentions (FRs) of individual fatty acids were also calculated by dividing the quantities of given fatty acids present in lipid accumulated by the fish by the quantities of corresponding fatty acids ingested in the diet. Lipogenic activity was evidenced by 16:0 and 18:0 having FRs greater than unity. FR values greater than unity for 18:3n-6 and 20:3n-6, and 18:4n-3 in diets containing low levels of HUFA demonstrated some bioconversion capacity from 18:2n-6 and 18:3n-3 precursors, respectively. FRs for n-3 HUFA were negative in fish fed 0.2% n-3 HUFA. In other treatments FRs of n-3 HUFA were 0.5 to 0.6, lower than other dietary fatty acids as linoleic (0.75) or linolenic (0.70) acids. Results indicated a basal loss of DHA estimated around 14 μg g−1 ABW d−1 during the experiment. We conclude that dietary requirements of HUFA by marine fish comprise not only quantities required for production of polar lipids during growth, but also quantities required to replace losses probably induced by the active roles of HUFA. The results also indicate that RI and FR transformations are useful tools for better understanding fatty acid incorporations in juvenile fish. [Copyright &y& Elsevier]

Abstract: The effects of essential fatty acid deficiency and temperature on the fatty acid profiles of polar lipids (PL) and neutral lipids (NL) from various tissues (muscle, liver, gills, eyes and brain) of European sea bass juveniles were compared in a two factorial design. Fish (60 g) were held for 84 days at 22 or 29 °C (upper limit for growth) and fed either at a lower or a higher level than n −3 HUFA minimal requirement for growth (0.4% and 2.2% n −3 HUFA dry matter for diets LD and HD, respectively). Essential fatty acid deficiency had a major influence on fatty acids in NL fraction of all tissues, a more moderate influence on PL of muscle, liver and gills, while a low and very low diet influence was observed on eyes and brain PL fatty acid content, respectively. DHA and EPA content in brain PL as well as DHA in eyes PL were not affected by diet. DHA contents were similar in gill PL of 22-HD, 29-HD and 22-LD but was reduced in 29-LD fish. Most of brain PL fatty acids displayed a significant effect of temperature (at 29 °C; 18:0, 18:1n −9 contents were higher, and 20:5n −3, 22:6n −3, 20:4n −6 contents were lower than at 22 °C). Temperature had more influence on PL than on NL fatty acid content, except in liver. A lipogenic activity seemed to occur, both 16:0 and 18:0 were high particularly in liver NL and dependent on temperature (higher at 29 than at 22 °C). An enhanced 18:3n −6 content in fish fed on the deficient HUFA diet indicated a desaturation activity, mainly in liver NL and gill PL, with higher arachidonic acid content in PL of gills than other tissues. Muscle fatty acid profiles in NL and PL were more similar to those of whole body than other tissues, however total lipid content then PL:NL ratio differed. This study shown that beside known characteristics of each tissue in term of PL fatty acid content, each tissue have also characteristics in term of response to temperature and dietary deficiency influence. Among then, neural tissue displayed the highest capacity to regulate DHA content in PL, preserving functionality despite HUFA deficiency. [Copyright &y& Elsevier]

Abstract: The Raman spectrum of natural PbS has been shown to exhibit features related to the IR-active (Raman forbidden) LO phonons and to allowed scattering by two phonons. In order to confirm the vibrational nature of these features, and their peculiar temperature dependence, we compare here the spectra obtained for natural samples (i.e. mineral as well as synthetic with the natural isotopic abundance) with those measured for crystals prepared from highly enriched 34S. The observed isotopic shifts confirm the vibrational nature of the structures mentioned above. We have also measured the spectra of synthetic samples of PbS annealed at several different pressures of sulphur. Because of their non-stoichiometric sulphur content they have carrier concentrations (either electrons or holes) in the 1×1017–3×1018 carriers/cm3 range (as determined from their IR reflection spectra). The measured spectra, as well as their temperature dependence, do not depend on the bulk carrier concentration, a fact that must result from surface pinning of the Fermi level within the fundamental energy gap. We finally discuss the apparent paradox of why the IR spectra reveal coupled LO-phonon–plasmon modes whereas the Raman spectra exhibit the bare LO-phonons. [Copyright &y& Elsevier]

Improvements in the instrumentation for dispersive and interferometric Fourier transform (FT) Raman microscopy have overcome many of the earlier limitations of these techniques, thus opening the way for their widespread and routine utilisation in archaeometry laboratories. The use of Raman spectroscopy for identifying and studying archaeological materials has flourished in recent years, but the resulting articles have seldom been published in the archaeology literature, thus limiting their impact on the field. Therefore, this article covers concisely the theory and instrumentation of Raman microscopy and then comprehensively reviews the many applications of this technique in archaeometric research. The significant advances made in archaeological science through the use of Raman microscopy are highlighted, but many areas requiring further research, such as the generation of more extensive and reliable spectral libraries and the surmounting of obstacles in the analysis of certain classes of historical materials, are also revealed. [Copyright &y& Elsevier]

Five Greek icons, made between the 15th and 18th centuries and now belonging to the Victoria and Albert Museum collections, were analysed by energy-dispersive X-ray fluorescence (EDXRF), optical microscopy and Raman microscopy in order to determine the stratigraphy of the artworks and the identity of the pigments used. Together with common pigments, such as red lake, vermilion, red lead, red iron oxide, orpiment, yellow ochre, lead white, chalk, gypsum, anhydrite, Prussian blue, indigo and a copper-containing green, a few unusual materials were identified, specifically pararealgar (a yellow arsenic sulphide, As4S4), its precursor the χ-phase, and lead tin yellow type II (PbSn1−xSixO3). Attention is drawn to the complementarity of the techniques used for the pigment identifications. [Copyright &y& Elsevier]

Recent advances have led to the development of inert diets for first-feeding marine fish larvae. The purpose of the present study was to evaluate fatty acid (FA) incorporation into larva using practical-type and semipurified diets as first food for larvae. Experimental microparticulate diets were fed to gilthead sea bream larvae, right from the mouth opening to day 21 post hatching. Five basal diets were compared, using fish meal or casein as main protein sources, and fish protein concentrate or casein hydrolysates and algae powder (Schizochytrium). Diets contained soybean lecithin to provide polar lipids and this also provided a high linoleic acid (18:2n-6) content. n-3 HUFA (1.5–1.7% DM) were mainly in dietary neutral lipids, with a part in polar lipids in diets containing fish meal or fish hydrolysates. Fatty acid incorporation was studied by analysing FA content of larvae at the beginning and at the end of the trial.A semipurified diet (casein+Schizochytrium powder) led to the best mean survival rate of 25% at day 21. While length increments were low, basal diets containing fish meal gave higher growth in size than casein-based diets. Whole body total fatty acid content differed between treatments and was higher in larvae fed casein-based diets than in those fed fish meal-based diets. As a result, fatty acid profiles shown showed various differences between treatments but not clearly related to dietary fatty acids. No clear sign of desaturation nor elongation of fatty acids was observed; the presence of 22:5n-6 (from Schizochytrium) into some diets did not seem to induce retroconversion to 20:4n-6 by larva. Fatty acid profiles incorporated into larvae were compared to those of diets in order to display common tendencies: the incorporation of n-6 fatty acids was higher than their relative proportion in the diets, even for 18:2n-6 despite high dietary supply; incorporation of 20:4n-6 was two- to fourfold higher than the proportion in diets (irrespective of the level of 22:5n-6). Among saturated FA, high stearate but low myristate incorporation was observed. Taking into account the high level of n-3 HUFA in the larvae before first feeding, n-3 long-chain PUFA were not selectively incorporated into larvae during feeding, with a negative tendency for EPA, and variable incorporation of DHA between treatments. [Copyright &y& Elsevier]

The fatty acid (FA) content of fish is generally said to reflect fatty acid composition of the diet. In fact, incorporation of FA into tissues is modulated by various metabolic factors, and final composition will depend upon the initial FA content, cumulative intake of dietary fatty acids, growth rate and duration. Analysis of time course of changes in FA composition should be easier with animals having different initial FA profiles, which are subsequently fed a diet with the same FA composition.Data from two studies, one with brown trout and another with turbot were used. Fish were first fed with diets containing one of three different oils (soybean oil (SO), linseed oil (LO) and fish oil (FO)), and subsequently fed the same fish oil-based diet (washout period). If we suppose a model fish having the same initial composition as those fed vegetable oil and which incorporate fatty acid in the same way as the control fish always fed fish oil, we may compute a model of dilution of initial fatty acid content with increasing growth and absolute fat deposition. Experimental data can be compared with a reference fatty acid profile given by this model for the same fatty acid increase.Application of the model to experimental data shows that while muscle neutral lipid (NL) FAs roughly follow this dilution model, those of muscle polar lipids (PL) undergo much faster changes than model values based on increase of total polar lipid quantities. Among observed differences between the model and experimental values, DHA is of particular interest as this fatty acid displays lower change rates (significant in turbot neutral lipids) than expected in contrast to other fatty acids. [Copyright &y& Elsevier]

Identifies the materials used in the construction of Vinland Map and Tartar Relation by Raman microprobe spectrometry. Raman spectra of the blank areas of parchment; Utilization of Renishaw System 100 in analyzing the map and manuscript; Identification of anatase in the yellow lines of the manuscript.

The Raman and infrared spectra of solid K212C2O4 · H2O are reported together with, for the first time, the corresponding Raman and infrared spectra of solid K213C2O4 · H2O. Raman spectra of aqueous solutions of both isotopomers are also reported. In the solid state the oxalate anion is planar with D2h symmetry in this salt, whereas in aqueous solution the Raman spectra of the anion are best interpreted on the basis of D2d symmetry. The Raman spectra of solid (NH4)212C2O4 · H2O and (NH4)213C2O4 · H2O, in which the oxalate anion is twisted from planarity by 28° about the CC bond, have also been recorded. Several reassignments have been made. The harmonic force field for the oxalate anion in the D2h, D2 and D2d geometries has been determined in part, and approximate values of key valence force constants determined. All the observed band wavenumbers and 12C/13C isotopic shifts are well reproduced by the force fields. The potential energy distribution of the totally symmetric normal modes of planar oxalate indicates that each mode consists of extensively mixed symmetry corrdinates and that the labels previously used for the bands seen here at 475 and 879 cm−1 would better be described as ν(CC) and δs(CO2), respectively, putting them in the same wavenumber order as ν(NN) and δs(NO2) for the isoelectronic and isostructural molecule N2O4. The stretching force constants of N2O4 and planar C2O42− are established to be in the order fNNfCO, consistent with the known relative bond lengths. [ABSTRACT FROM AUTHOR]

Pigment identification on manuscripts, paintings, ceramics and papyri is critical in finding solutions to problems of restoration, conservation, dating and authentication in the art world. The techniques (molecular and elemental) used for these purposes are reviewed and compared, particular attention being given to Raman microscopy and laser-induced breakdown spectroscopy. These give excellent results in respect of reproducibility, sensitivity, non-destructiveness, immunity to interference from adjacent materials, and depth-profile analysis. New advances in optics provide powerful and long needed links for Arts- and Science-based projects. To cite this article: R.J.H. Clark, C. R. Chimie 5 (2002) 7–20 [Copyright &y& Elsevier]

Traces the origin, use and history of ancient dyes indigo, woad and Tyrian Purple. Emphasis on the chemistry of the production and syntheses of the dyes; Production of natural indigo from the leaves of Indigofera tinctoria by fermentation; Manufacture of synthetic indigo; Rediscovery of the Tyrian Purple by William Cole of Bristol in 1684.

Elaborates on the contentions made on the subject of human assortative mating and questions Rushton's assertions on the subject.

Examines the influence of personality on quality of marriage using causal modeling on a sample of 94 couples who had completed a quality of marriage scale and the revised short form of the Eysenck Personality Questionnaire. Negative influence of spouse's neuroticism; Strongest causal influence.

Looks at the use of analytical chemistry techniques to identify pigments on historical artifacts. Background on the study of Raman microscopy; Details on procedures of the technique; History of the technique.

Reports on nuclear magnetic resonance (NMR) spectra results for [NMe4]2Se5 and [NME4]2Se6 selenide complexes. Isotropic chemical shifts; Single-crystal X-ray structure determinations.

Investigates by 77Se solid-state NMP spectroscopy the properties of [M(Se4)2]2- anions [Me4N]+ (M = Zn, Cd, Hg) and [Et4N]+ (M = Cd, Hg). Differences between the 77Se isotropic chemical shifts observed for the [Et4N] and [Me4N]+ complexes.

Highlights: [•] Raman spectra of historical anatase samples synthesised by the Kronos-Titan NV Company. [•] Raman spectroscopy identified the difference between products of 1923 and 1968. [•] Barium sulfate is detected only in early anatase samples. [•] The results could be used in dating artwork. [Copyright &y& Elsevier]

Probes the reversible and irreversible redox processes displayed by (Re2(NCS)10)3- using voltammetric and in situ spectroelectrochemical techniques. Infrared and ultraviolet/visible spectroscopic data; Single scan infrared spectra of (Re2(NCS)10)z- complexes.

Abstract: The palette of four Persian manuscripts of the 16th and 17th centuries were established by Raman microscopy to include lazurite, red lead, vermilion, orpiment, a carbon-based black, lead white, malachite, haematite, indigo, carmine and pararealgar. The first five pigments were identified on all four manuscripts, as previously found for other Islamic manuscripts of this period. The findings were compared with information available in treatises on Persian painting techniques. Red lead, although identified on all of the manuscripts analysed in this study as the main red pigment, is seldom mentioned in the literature. Two unusual pigments were also identified: the intermediate phase between realgar and pararealgar in the manuscript Timur namah, and carmine in the manuscript Shah namah. Although the established palette comprises few pigments, it was found that the illuminations were enhanced by the use of pigment mixtures, the components of which could be identified by Raman microscopy. [Copyright &y& Elsevier]

Mixed-valence compounds were recognized by chemists more than a century ago for their unusual colours and stoichiometries, but it was just 40 years ago that two seminal articles brought together the then available evidence. These articles laid the foundations for understanding the physical properties of such compounds and how the latter correlate with molecular and crystal structures. This introduction to a discussion meeting briefly surveys the history of mixed valence and sets in context contributions to the discussion describing current work in the field. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this study was to check if it is possible to influence sea bass juvenile metabolism by a conditioning of larvae from day 6 post hatching to day 45 to a low or a high HUFA compound diet (LH, 0.8% EPA+DHA and HH, 2.2% EPA+DHA) when reared at 16 or 22 °C. Following a 3-month intermediate period (at 19 °C using a commercial diet), the adaptability of the 4 initial larval groups to a HUFA experimental deprived diet (0.5% EPA+DHA) were tested at 19 °C in a 60 day-experiment (d-151–211). The four experimental duplicated conditions were ex-LH16 and ex-HH16 for the 2 groups previously reared at 16 °C (initial weight, 7.3±0.5 g) and ex-LH22 and ex-HH22 for the 2 groups previously reared at 22 °C (initial weight, 11.1±0.5 g). Survival was maximal and there was a 1.6–2 fold increase in mass during the experiment. Growth was similar in the 4 experimental groups: NS difference in growth curve slopes (P =0.7). At the end of the experiment (d-211), whole body fat levels were in the same range in all groups (13–15% WW). The fatty acid (FA) composition in polar lipids (PL) and total lipids (TL) were significantly affected by initial weight related to larvae conditioning, which can be mainly attributed to a dilution effect (impact of initial FA content on final FA content versus relative mass increase during the course of the experiment). Conversely to this trend, DHA content in PL was higher in the ex-LH groups than in the ex-HH groups whatever thermal conditioning of larvae was. This indicated that ex-LH groups had a better capacity to adapt to a deficient HUFA diet than ex-HH fish. The relative expression of the delta-6 desaturase (Δ6D) was significantly higher in ex-LH than in ex-HH groups (P <0.001) between d-151 and d-181, which suggested that Δ6D transcription in ex-LH groups was positively modulated by the HUFA-deprived diet. This stimulation of the first step of the desaturation/elongation pathway could allow synthesizing FA needed to compensate low dietary HUFA supply. This study shows for the first time that it seems possible to influence juvenile fish metabolism by a nutritional conditioning during the larval stage. [Copyright &y& Elsevier]

Abstract: The pigments identified on four beautiful icons painted by Constantin Ieromonachou during the late 17th century in churches of the medieval city of Voskopoja (Moschopolis) in south-east Albania have been identified. The analysis was carried out to establish whether the same pigments were used on all the icons and whether this information could form a basis for future restorations. Total reflection X-ray fluorescence (TXRF) and Raman microscopy (RM) were both used to identify the pigments and the combination of techniques minimised the number and amount of samples which needed to be taken from each icon for the analyses. The main pigments identified were white lead, carbon black, indigo, gold, red ochre, red lead, ochre, gypsum, vermilion and a copper-based green. [Copyright &y& Elsevier]

The compounds [([sup t]BuCO[sub 2])[sub 3]M[sub 2](µ-O[sub 2]CC[sub 6]F[sub 4]CO[sub 2])M[sub 2](O[sub 2]C[sup t]Bu)[sub 3]], M[sub 4]PFT, where M = Mo or W, are shown by model fitting of the powder X-ray diffraction data to have an infinite "twisted" structure involving M···O intermolecular interactions in the solid state. The dihedral angle between the M[sub 2] units of each molecule is 54°. Electronic structure calculations employing density functional theory (Gaussian 98 and ADF2000.01, gradient corrected and time dependent) on the model compounds (HCO[sub 2])[sub 3]M[sub 2](µ-O[sub 2]CC[sub 6]F[sub 4]CO[sub 2])M[sub 2](O[sub 2]CH)[sub 3], where M = Mo or W, reveal that in the gas phase the model compounds adopt planar D[sub 2h] ground-state structures wherein M[sub 2] δ to bridge π[sup *] back-bonding is maximized. The calculations predict relatively small HOMO-LUMO gaps of 1.53 eV for M = Mo and 1.22 eV for M = W for this planar structure and that, when the "conjugation" is removed by rotation of the plane of the C[sub 6]F[sub 4] ring to become orthogonal to the M[sub 4] plane, this energy gap is nearly doubled to 2.57 eV for M = Mo and 2.18 eV for M = W. The Raman and resonance Raman spectra of solid M[sub 4]PFT and of Mo[sub 4]PFT in THF solution are dominated by bands assigned to the bridging perfluoroterephthalate (pft) group. The intensities of certain Raman bands of solid W[sub 4]PFT are strongly enhanced on changing the excitation line from 476.5 nm (off resonance) to 676.5 nm, which is on resonance with the W[sub 2] δ → CO[sub 2] (pft) π[sup *] transition at ca. 650 nm. The resonance enhanced bands are δ[sub s](CO[sub 2]) (pft) at 518 cm[sup -1] and its first overtone at 1035 cm[sup -1], consistent with the structural change to W[sub 4]PFT expected on excitation from the ground to this π[sup *] excited state. The electronic transitions for solid Mo[sub 4]PFT (lowest at 410 nm)... [ABSTRACT FROM AUTHOR]

The compounds [(BuCO[sub 2])[sub 3]M[sub 2](μ-O[sub 2]CC[sub 6]F[sub 4]CO[sub 2])M[sub 2](O[sub 2]CBu)[sub 3]], M[sub 4]PFT, where M = Mo or W, are shown by model fitting of the powder X-ray diffraction data to have an infinite "twisted" structure involving M...O intermolecular interactions in the solid state. The dihedral angle between the M[sub 2] units of each molecule is 54°. Electronic structure calculations employing density functional theory (Gaussian 98 and ADF2000.01, gradient corrected and time dependent) on the model compounds (HCO[sub 2])[sub 3]M[sub 2](μ-O[sub 2]CC[sub 6]F[sub 4]CO[sub 2])M[sub 2](O[sub 2]CH)[sub 3], where M = Mo or W, reveal that in the gas phase the model compounds adopt planar D[sub 2]h ground-state structures wherein M[sub 2] δ to bridge π[sup *] back-bonding is maximized. The calculations predict relatively small HOMO LUMO gaps of 1.53 eV for M = Mo and 1.22 eV for M = W for this planar structure and that, when the "conjugation" is removed by rotation of the plane of the C[sub 6]F[sub 4] ring to become orthogonal to the M[sub 4] plane, this energy gap is nearly doubled to 2.57 eV for M = Mo and 2.18 eV for M = W. The Raman and resonance Raman spectra of solid M[sub 4]PFT and of Mo[sub 4]PFT in THF solution are dominated by bands assigned to the bridging perfluoroterephthalate (pft) group. The intensities of certain Raman bands of solid W[sub 4]PFT are strongly enhanced on changing the excitation line from 476.5 nm (off resonance) to 676.5 nm, which is on resonance with the W[sub 2] δ → CO[sub 2] (pft) π[sup *] transition at ca. 650 nm. The resonance enhanced bands are δ[sub s](CO[sub 2]) (pft) at 518 cm [sup -1] and its first overtone at 1035 cm[sup -1], consistent with the structural change to W4PFT expected on excitation from the ground to this π[sup *] excited state. The electronic transitions for solid Mo[sub 4]PFT (lowest at 410 nm) were not accessible with the available... [ABSTRACT FROM AUTHOR]

Examines the complexes of dimolybdenum and ditungsten supported by pivalate ligands. Analysis on the powder X-ray diffraction of the complexes; Spectra of the isotopomers; Transitions dominating the visible region of the electronic spectra.

Abstract: TiO2 doped with various loadings of nitrogen was prepared by nitridation of a nano-TiO2 powder in an ammonia/argon atmosphere at a range of temperatures from 400 to 1100°C. The nano-TiO2 starting powder was produced in a continuous hydrothermal flow synthesis (CHFS) process involving reaction between a flow of supercritical water and an aqueous solution of a titanium salt. The structures of the resulting nanocatalysts were investigated using powder X-ray diffraction (XRD) and Raman spectroscopy. Products ranging from N-doped anatase TiO2 to phase-pure titanium nitride (TiN) were obtained depending on post-synthesis heat-treatment temperature. The results suggest that TiN started forming when the TiO2 was heat-treated at 800°C, and that pure phase TiN was obtained at 1000°C after 5h nitridation. The amounts and nature of the Ti, O and N at the surface were determined by X-ray photoelectron spectroscopy (XPS). A shift of the band-gap to lower energy and increasing absorption in the visible light region, were observed by increasing the heat-treatment temperature from 400 to 700°C. [Copyright &y& Elsevier]

Abstract: Nanosized TiO2 powder of high surface area was prepared from an aqueous solution of titanium(IV) bis(ammonium lactato) dihydroxide using a continuous hydrothermal flow synthesis (CHFS) reactor which uses superheated water at 400°C and 24.1MPa as a crystallizing medium. Freeze-dried nano-TiO2 was heat-treated in air over a range of temperatures and then the resulting powders were characterized using X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), BET surface area measurement, and Raman spectroscopy. The particle size of the ‘as-prepared’ TiO2 made using CHFS was ca. 4.8nm (by HR-TEM), and grew with increasing heat-treatment temperature. It was found that the onset of the anatase–rutile transition of heat-treated nano-TiO2 in air occurred at 500°C and reached 100% rutile at 900°C. The Raman band (E g) at ∼150cm−1 of anatase (nano-TiO2) softens as the particle size increases with heat-treatment temperature (up to 600°C). The photocatalytic activity of the TiO2 powders for the decolourisation of methylene blue dye was assessed. The effects of nano-TiO2 anatase-rutile phase composition, crystallinity, and crystallite size on the catalytic activity were investigated. [Copyright &y& Elsevier]

Abstract: Triplicate groups of European sea bass juveniles (60 g) were fed for 84 days two experimental diets containing either vegetable or marine oil (0.4 and 2.2% n−3 highly unsaturated fatty acid [n−3 HUFA] dry matter in LD and HD, respectively) and held at 22 or 29 °C (LD-22, LD-29, HD-22 and HD-29 groups). Significant differences in mass gain between the two diets and temperatures were observed from day 28 onwards, and on day 84, weight was 18% higher in the HD-29 group than in the LD-22 group (the highest and lowest values, respectively). Over the 84-day period, SGR was significantly affected both by temperatures and diets (P=6×10−4 and 2×10−4 respectively), averaging 1.01 and 1.07 in the HD-22 and HD-29 groups compared to 0.92 and 1.0 in the LD-22 and LD-29 groups. Differences in growth rate between the experimental conditions were mainly explained by differences in feed intake (FI). FI was more affected by temperature than by diets (in fish fed HD, it was 1.7% day−1 at 29 °C and 1.4% day−1 at 22 °C, and 1.7% day−1 and 1.3% day−1, respectively, with LD). Feed conversion ratio (FCR) was significantly affected by temperature and diets; days 0–84 FCR was on HD and LD 1.6 and 1.7 at 29 °C and 1.4–1.5 at 22 °C. Considering growth and feeding parameters, no interaction between dietary concentration in n−3 HUFA and temperatures were observed. In acclimated fish, MO2 on routine metabolism was the highest at HD-29 (396 mg O2 kg−1 h−1) as it was dependent on FI. There was no major difference in fish whole body composition, and protein retention was more affected by temperature than by diets. Diets and temperature affected polar lipid fatty acid content, without interaction; n−3 HUFAs were lower at 29 °C than at 22 °C. Fatty acids of total and neutral lipids (NL) were mainly affected by dietary fatty acids, while some low but significant influences of temperature were observed. Interactions between the two studied factors concerned particularly n−3 HUFAs content, lower at 29 than at 22 °C only in fish fed vegetable oil (LD). This study demonstrated that in high-quality sea bass juveniles, a 3-month deficiency in dietary n−3 HUFA did not drastically impair fish capacity to adapt to a high temperature, 29 °C. [Copyright &y& Elsevier]

Raman and infrared microscopy have been used to characterise the black pigments on prehistoric Southwest American black-on-white pottery. Conclusive spectroscopic evidence for the use of carbon-based paints on these sherds has been provided using the Raman technique. Maghaemite (γ-Fe2O3) and magnetite (Fe3O4), found alternatively or mixed with a carbonaceous pigment, were also identified on some sherds. Infrared measurements indicated that little, if any, organic material from biogenic precursors of the black pigment or from pigment binding agents remained in the paints. These spectroscopic results were obtained rapidly and non-destructively on unprepared samples, and the resulting data complement, and in some instances correct, paint type conclusions drawn from studies involving techniques such as XRD, SEM-EDX, and XPS. [Copyright &y& Elsevier]

A detailed investigation of iron oxide inclusions in a 19th century Russian platinum coin is presented. Such coins represent the products of the first industrial-scale purification of platinum metal. The processed metal is far from pure, however, and two types of iron oxide inclusions are identified by electron microprobe and Raman microscopy. The results show that the inclusions mainly consist of magnetite and haematite. The Raman band of magnetite at 668 cm−1 was found to shift to about 680 cm−1 with an increase in the average oxidation state of the iron. It is concluded that the iron oxides are formed during the heating of the platinum metal powder in the manufacturing process. [Copyright &y& Elsevier]

Reports on the crystal structure and physical properties of a conducting molecular charge-transfer salt where the cavity is occupied only by CH[sub 2]Cl[sub 2]. Thermal ellipsoids and atom labeling of beta''-(BEDT-TTF)[sub 4][(H[sub 3]O)Cr(C[sub 2]O[sub 4])[sub 3]]CH[sub 2]Cl[sub 2] compound; Representation of the docking of the BEDT-TTF with the [(H[sub 3]OCr(C[sub 2]O[sub 4])[sub 3]] layer.

Four-year-old pollackPollachius pollachiusL., previously fed on dry pellets since their juvenile stage, were divided into three experimental groups two months prior their first spawning season. They were fed a commercial broodstock pellet enriched with 6% added oils, either:(1) capelin oil(control),(2) capelin oil plus arachidonic acid, or(3) DHA rich tuna oil. Spawning performance was determined in each group and egg lipids were analysed. During the vitellogenic period, the estradiol levels in plasma increased with oocyte enlargement, indicating that captivity and pelleted feed did not affect reproductive capacity. Females from each group spawned spontaneously between February and May. Egg production per kg of female was highest in the control group. Fertilization rate was highest(39%) in the group fed on diet enhanced in DHA. Lipid content in eggs reached 16% of dry mass, containing mainly phospholipids(75%). Egg fatty acid profiles showed few differences between dietary treatments. There was no significant difference in the concentration of Docosahexaenoic acid(22:6n − 3) between groups. Arachidonic acid(20:4n − 6) was lower in neutral and polar lipids of eggs from the control group than in the other groups. Tuna oil diet induced the highest DHA/EPA ratio in eggs and seemed to provide sufficient arachidonic acid for pollack broodstock. Egg fatty acid profiles are compared with 6 year-old pollack broodstock fed on fish, and with other cultured and wild fish species. [ABSTRACT FROM AUTHOR]