bluuebunny/crossref_metadata_2025_split huggingface dataset:
Accurate‐mass identification of chlorinated and brominated products of 4‐nonylphenol, nonylphenol dimers, and other endocrine disrupters
Authors: Thurman E. Michael 
Published: September 2006

AbstractLC/ToF‐MS was used to identify new chlorination and bromination products of 4‐nonylphenol (4‐NP), such as 4‐NPBr2, 4‐NPBrCl, 4‐NP dimer (2 isomers), 4‐NPCl dimer (2 isomers), 4‐NPBr dimer, and a series of methoxy bromo and chloro 4‐NPs from a laboratory study of nonylphenol chlorination. The identification procedure used the exact mass, exact mass of the isotope cluster, and their relative intensities, at an average mass accuracy of ∼1 ppm. The products were produced by a simulated study of industrial cleaning procedures where 4‐NP, nonylphenol ethoxylate (NPEO‐1 and 2), and nonylphenol carboxylate (NPEC‐1) were in contact with sodium hypochlorite solutions (with and without bromide) of various strengths (possible environmental scenarios) at neutral pH. The formation of the products was measured as a function of chlorine concentration, and it was found that 4‐NP was the most reactive, producing 4‐NPCl, 4‐NPCl2, 4‐NP (dimers), and the 4‐NPCl (dimers). In the presence of bromide ions, a mixture results with products of 4‐NPBr2, 4‐NPCl, 4‐NPCl2, 4‐NPBrCl, 4‐NPBr, and a 4‐NPBr dimer. Less reactive to halogenation was NPEO, which formed only the monochloro and monobromo products, and the least reactive was NPEC. A simple stereochemical model is used to explain halogenation reactivity for the family of 4‐NPs and NPEOs at neutral pH. The presence of halogenated 4‐NP dimers (bromo and chloro diphenyl ethers) is discussed as a possible source of new endocrine disrupters. Copyright © 2006 John Wiley & Sons, Ltd.
Prehistoric Anasazi ceramics studied by micro‐Raman spectroscopy
Authors: Striova Jana , Lofrumento Cristiana , Zoppi Angela , Castellucci Emilio Mario 
Published: September 2006

AbstractIn this project, micro‐Raman (µ‐Raman) spectroscopy has been used as a means to investigate the pigments employed in decoration of Anasazi pottery. Analysis of Raman spectra revealed the presence of organic‐ (amorphous carbon), iron‐ and/or manganese‐based pigments in line with the known pictorial materials used by Anasazi people. The results were also complemented by studies employing a scanning electron microscope equipped with a microanalysis energy dispersive X‐ray detection (SEM/EDX) system, which proved helpful mainly while identifying the manganese‐based minerals (i.e. pyrolusite). Knowledge of the pigments augments our understanding of the materials favored by the different production centers and of the artistic skills of ceramic producers. Copyright © 2006 John Wiley & Sons, Ltd.
Optimum acquisition of Raman spectra in pigment analysis with IR laser diode and pulsed UV irradiation
Authors: López‐Gil Alejandro , Ruiz‐Moreno Sergio , Miralles Judith 
Published: September 2006

AbstractFluorescence, due to the binding media, is the main problem that one encounters in the molecular analysis of artistic pigments using Raman spectroscopy. With the object of minimizing this problem, we propose the use of a semiconductor IR laser in Raman spectral acquisition and the application of local irradiation with a pulsed UV laser on the analysis zone. The Raman analysis with an IR source shows advantages compared to that with visible lasers, such as the reduction of fluorescence and its shot noise, although a price has to be paid in the form of the small intensity of the obtained spectra with the same acquisition time. Also, in this paper we demonstrate that controlled levels of pulsed UV radiation over the analyzed painting (pigment + binding media) can improve even more the Raman spectral quality obtained with the IR laser, which leads us to conclude that the local use of a pulsed UV laser, prior to Raman analysis with the IR source, can bring optimum quality results in pigment identification. The spectral quality of these experimental results for different pigments has been measured by calculating in each case the signal‐to‐noise ratio (SNR) of the corresponding spectra. From a quantitative point of view, in some practical cases (chromium yellow and ultramarine blue) an SNR improvement of 16 dB is achieved when pulsed UV irradiation and IR laser Raman analysis are used instead of a simple Raman analysis with a visible laser. Copyright © 2006 John Wiley & Sons, Ltd.
Experimental confirmation by Raman spectroscopy of a PbSnSb triple oxide yellow pigment in sixteenth‐century Italian pottery
Authors: Sandalinas C. , Ruiz‐Moreno S. , López‐Gil A. , Miralles J. 
Published: September 2006

AbstractThe sixteenth and seventeenth‐century Venetian manuscripts on glassmaking contain a number of recipes on yellow pigment production, later named ‘anime’, based on PbSn and/or PbSb oxides. Since antiquity, these oxides have been employed intermittently as opacifying and colouring agents to obtain coloured glasses, enamels and pigments.In 1998, different laboratories provided evidence of the existence of a ‘non‐standardized’ yellow pigment (PbSnSb triple oxide) very close in composition and structure to both the PbSn type II (silicoestannate) and PbSb (antimonate) oxides. This PbSnSb yellow pigment was identified by SEM‐EDX in seventeenth‐century Italian paintings.In previous studies, the authors of the present work have investigated with Raman spectroscopy the presence of PbSnSb oxide (pyrochlore structure) in some Italian paintings of the seventeenth century, using as standard a synthesized pyrochloric triple oxide (Pb2SnSbO6.5).In this paper, we provide evidence for the first molecular identification with Raman spectroscopy of said pigment in Italian pottery from the sixteenth century. We have identified this pigment in two pieces of decorated pottery: a ‘plate’ manufactured in Casteldurante and attributed to Andrea Negroponte style (c 1550), and a Venetian ‘albarello’ (pharmacy jar) attributed to Domenego (c 1570–1580). We have synthesized the reference compound in accordance with the theoretical formula of the pyrochloric triple oxide (Pb2SnSbO6.5). The Raman spectra obtained with this material provided molecular information identical to the yellow pigment measured in the two Italian ceramics. To conclude, the experimental results presented here indicate one simple fact: Pb–Sn–Sb triple oxide yellow pigment has been used during the sixteenth and seventeenth centuries without distinction both in Italian ceramics and paintings. Copyright © 2006 John Wiley & Sons, Ltd.
Raman spectroscopy investigations of the weathering alteration of a predazzite marble mouflon of the Indus Valley Culture
Authors: Twilley John 
Published: September 2006

AbstractA recumbent ram carved in the style of Mohenjo Daro was examined by a variety of scientific methods in order to clarify questions regarding its condition and the possible recarving of certain details. Testing consisted of microstructural and compositional analysis of the stone and mineral accretions found on it utilizing the complementary methods of Raman spectroscopy, scanning electron microscopy/X‐ray spectrometry, Fourier‐transform infrared spectroscopy and optical petrography. The case demonstrates both the strengths and weaknesses of Raman spectroscopy, and argues for the need for an integrated analytical approach. Significant deviations from the nominal Raman emission wavenumbers were found for both the primary minerals and their weathering products. Consistent differences in Raman spectra between primary and secondary forms of calcite allowed their differentiation in the weathering zone. Exceptionally clear phases led to occasional difficulties in the analysis of petrographic sections due to the excitation of Raman emission from grains below, or adjacent to, the grain of interest. The ram, previously misidentified as a sandstone, was found to have been carved from a marble‐like stone of mixed mineral composition known as predazzite. Despite a deceptively simple appearance, the ram possesses abundant evidence of natural alteration of the carved surface. This alteration takes several forms, including transformation of brucite into hydromagnesite by hydration and carbonation; the loss, by dissolution, of hydromagnesite from the subsurface with resulting void formation; the replacement of subsurface hydromagnesite by void‐filling aragonite or calcite; and the formation of calcite incrustations atop parts of the stone surface. Surface pores produced by weathering create the appearance of sandstone or porous limestone, rock types that are quite different from the much rarer predazzite. The identification of similar artworks as sandstone or limestone should be viewed with skepticism, as published identifications are often not the result of actual mineralogical study. New avenues of archaeometric research, including the determination of the geological source of the stone, should be possible for sculptures of this type on the basis of the fact that predazzites are relatively rare and limited in geological extent. If multiple quarry sites exist in the Indus Valley region, they should be amenable to differentiation by techniques that have proven successful for marbles of the Mediterranean, such as electron paramagnetic resonance spectroscopy, grain size analysis, and carbonate stable isotope analysis. Copyright © 2006 John Wiley & Sons, Ltd.
Raman microscopic investigation of paint samples from the Rosalila building, Copan, Honduras
Authors: Goodall Rosemary A. , Hall Jay , Viel Rene , Ricardo Agurcia F. , Edwards Howell G. M. , Fredericks Peter M. 
Published: September 2006

AbstractMicro‐Raman spectroscopy was applied to the study of multiple layered wall paints from the Rosalila temple, Copan, Honduras, which dates to the Middle Classic period (A.D. 520 to 655). Samples of red, green and grey paint and a thick white overcoating were analysed. The paint pigments have been identified as hematite, celadonite or green earth and a combined carbon/mica mixture. By combining Raman spectroscopy with micro‐ATR infrared spectroscopy and environmental scanning electron microscopy (ESEM), a detailed study has been made of the materials and processes used to make the stucco and paints. The use of green earth as a green pigment on Maya buildings has not been reported before. The combination of carbon and muscovite mica to create a reflective paint is also a novel finding. Copyright © 2006 John Wiley & Sons, Ltd.
On the Raman spectrum of Maya blue
Authors: Sánchez del Río Manuel , Picquart Michel , Haro‐Poniatowski Emmanuel , van Elslande Elsa , Hugo Uc Victor 
Published: September 2006

AbstractMaya blue is a marvelous pigment with extraordinary properties. It was invented by the Maya around VII–VIII century and used by many Mesoamerican peoples in prehispanic times. It is made by encapsulating natural indigo into an inorganic clay matrix of palygorskite. The palygorskite–indigo mixture becomes acid‐resistant when a moderate thermal treatment is applied. The chemical reasons of the unusual stability of the pigment and the exact mechanism of interaction between the indigo and the clay are not well understood. We present a Raman study of different preparations of Maya blue and other mixtures of indigo with other inorganic materials. We found that the unheated mixture of indigo with palygorskite presents the same Raman spectrum as Maya blue, indicating that the differences with respect to the indigo spectrum are not due to the interaction produced during the thermal treatment, which makes the mixture acid‐resistant. Moreover, indigo mixed with other clays, like sepiolite or montmorillonite, presents a Raman spectrum very similar to that of Maya blue. Some chemical mechanisms that could explain these spectra, and the suitability of Raman spectroscopy for identifying Maya blue are discussed. Copyright © 2006 John Wiley & Sons, Ltd.
Non‐destructive micro‐Raman and X‐ray fluorescence spectroscopy on pre‐Eyckian works of art—verification with the results obtained by destructive methods
Authors: Fremout Wim , Saverwyns Steven , Peters Famke , Deneffe Dominique 
Published: September 2006

AbstractThe applicability of non‐destructive techniques such as micro‐X‐ray fluorescence spectroscopy, which reveals atomic composition, and fibre‐coupled micro‐Raman spectroscopy, which reveals molecular information, is explored on three pre‐Eyckian works of art: a small shrine of Saint Ursula, two small panels depicting the Saints Arnulf, Godeleva, Livinus and Margaret and the relic holder with fragment of the veil of the Holy Virgin. The results are consistent with those obtained by destructive means—optical microscopy (OM), SEM‐EDX and micro‐Raman spectroscopy on embedded stratigraphic samples. In the case of multilayered paint, however, the results of the non‐destructive techniques are difficult to interpret and much information about the original layers is lost. In those cases, non‐destructive methods need to be supplemented by a limited number of stratigraphic samples, while the former—when well considered—limit the number of samples needed for a broad study. Copyright © 2006 John Wiley & Sons, Ltd.
Raman spectroscopy in art and archaeology
Authors: Bellot‐Gurlet Ludovic , Pagès‐Camagna Sandrine , Coupry Claude 
Published: September 2006

AbstractThis paper gives a short overview of the Special Issue on Raman Spectroscopy in Art and Archaeology, with the papers collected after the ‘3rd International Conference on the Application of Raman Spectroscopy in Art and Archaeology’ held at the University Pierre et Marie Curie‐Paris 6, Paris, France, from 31 August to 3 September, 2005. The contributions present an extended view of the work in the field, from technical developments and special analytical procedures to various applications. Copyright © 2006 John Wiley & Sons, Ltd.
Leaching of aluminium from utensils during cooking of food
Authors: Semwal Anil D , Padmashree A , Khan Mohammed A , Sharma Gopal K , Bawa Amrinder S 
Published: September 2006

AbstractThe use of aluminium utensils for cooking provides an important route for aluminium metal to enter foods. Leaching of aluminium from utensils made of aluminium, indalium (alloy of aluminium), stainless steel and hard anodised aluminium was studied under different conditions of pH and boiling time. Low pH was found to enhance leaching of aluminium from the utensils. The leaching was found to be the highest during first‐time preparation (new utensils) of all the foods as compared with second‐and third‐time preparations using the same utensils. Leaching of aluminium during the preparation of various traditional Indian foods was found to be negligible in hard anodised aluminium utensils, indicating the advantage of using such vessels for food preparation over simple aluminium and indalium utensils. Cereals contribute a smaller amount of aluminium to the total daily intake than legumes. Copyright © 2006 Society of Chemical Industry
Drying temperature, endogenous antioxidants and capsaicinoids affect carotenoid stability in paprika (red pepper spice)
Authors: Daood Hussein G , Kapitány József , Biacs Péter , Albrecht Katalin 
Published: September 2006

AbstractThe major carotenoids and carotenoid esters in Capsicum annuum L. during thermal dehydration of pepper and storage of the ground product (paprika) were examined with special focus on the role of endogenous antioxidants such as vitamins E and C and capsaicinoids, the pungent materials in hot spice red pepper. A high‐performance liquid chromatographic (HPLC) method was developed to achieve excellent separation and accurate detection of different carotenoid classes including free xanthophylls, monoesters, carotenes and di‐esters. The newly developed method included gradient elution on a reversed‐phase column with increasing proportions of isopropanol. The results indicated that presence of capsaicinoids in pungent pepper had a favourable effect on the stability of carotenoids during thermal drying. Among various di‐esters those of lutein and zeaxanthine, as well as the mono‐ester of β‐cryptoxanthin were more stable than those of capsorubin and capsanthin, pointing to the possible role of epoxide and carbonyl groups in the susceptibility of carotenoids. An Arrhenius plot for degradation of carotenoids, tocopherols and ascorbic acid as a function of drying temperature showed linear relationships for all components, with ascorbic acid being the most sensitive. During storage in a refrigerator for 3 months the paprika showed high degradation of all the examined carotenoids particularly in samples prepared from pods dried at high temperatures (90 and 100 °C). An exception was for β‐cryptoxanthin mono‐ester and violaxanthin di‐esters in a non‐pungent variety. The amounts of these carotenoids lost during storage were slightly affected by the change in drying temperature. Strong correlation was found between retention of colour in stored paprika and the initial content of ascorbic acid, but not with that of tocopherols or capsaicinoids. Copyright © 2006 Society of Chemical Industry
Effect of cold‐shock treatment on chilling injury in mango (Mangifera indica L. cv. ‘Wacheng’) fruit
Authors: Zhao Zhilei , Jiang Weibo , Cao Jiankang , Zhao Yumei , Gu Yuhong 
Published: September 2006

AbstractTo investigate how cold shock may affect chilling injury in mango fruit (Mangifera indica L. cv. ‘Wacheng’), the fruit were treated for 3, 4 or 5 h at 0 °C, or treated for 8, 10 or 12 h at 4 °C, respectively, then transferred to 20 °C for 20 h prior to being stored at 2 °C, 85–95% RH. The chilling injury index of mango treated at 0 °C for 4 h was 59.7% lower than that of the control fruit directly stored at 2 °C, 85–95% RH. Some attributes were assayed in the fruit treated at 0 °C for 4 h. Ion leakage of the cold‐shock fruit at 0 °C for 4 h was 16% or 10% lower than that of the control on day 9 or day 12 of storage, respectively. Malondialdehyde content of the cold‐shocked fruit was 70% or 50% lower than that of the control on day 6 or day 12 of storage at 2 °C, respectively. Activities of catalase, ascorbate peroxidase, and contents of glutathione and phenolic compounds in the fruit during storage were all markedly enhanced by the cold‐shock treatment, whereas activities of superoxide dismutase, glutathione reductase and content of ascorbic acid in the mango were slightly influenced by the cold‐shock treatment. These results suggest that cold‐shock treatment may hold promise as an alternative approach to reduce chilling injury in mango fruit during cold storage. Copyright © 2006 Society of Chemical Industry
The influence of malolactic fermentation and Oenococcus oeni strain on glycosidic aroma precursors and related volatile compounds of red wine
Authors: Ugliano Maurizio , Moio Luigi 
Published: September 2006

AbstractFree and glycosidically bound volatile compounds of red wine were measured after malolactic fermentation (MLF) with four different commercial starter cultures of Oenococcus oeni. MLF resulted in a significant decrease in the concentration of total glycosides, expressed as phenol‐free glycosyl glucose. Gas chromatographic analyses of wine enzyme hydrolysates showed that the extent of hydrolysis of glycosides during MLF was dependent on both bacterial strain and chemical structure of the substrate. The highest decrease was observed for glycosidic precursors of primary terpene alcohols. Glycoside‐related aroma compounds such as linalool, farnesol, and β‐damascenone were increased after MLF with all the bacterial strains tested. Two of the strains were also able to release significant amounts of vinylphenols during MLF. Copyright © 2006 Society of Chemical Industry
Determination of acrylamide content of food products in Korea
Authors: Koh Bong‐Kyung 
Published: September 2006

AbstractAcrylamide (AA) contents of commercial market‐purchased foods and of traditional home‐cooked Korean foods were investigated. The effect of cooking method on AA amount in potatoes was also studied. AA contents of roasted barley and corn ranged from 116 to 449 µg kg−1 and of chips ranged from 12 to 3241 µg kg−1, representing a very high variation in AA contents among tested samples. Lower levels of AA were found in wheat flour chips compared to potato chips. AA contents of ramen noodles were below 37 µg kg−1, whether they contained potato starch or not. The AA contents of Korean home‐cooked oil fried foods increased in the following order: yakwa < whole deep‐fried sea tangle < ground and deep‐fried lotus root < ground and pan‐fried lotus root < French fries < ground and pan‐fried potato. Lotus root and garlic also had the potential to produce AA during cooking. Pre‐treatment such as grinding, boiling, freezing and thawing increased the AA formation in oil‐fried potato. Temperature was more influential than time on AA formation during deep‐oil frying. Removing water‐soluble fractions reduced AA content of cooked potatoes. Copyright © 2006 Society of Chemical Industry
Rainfall temporal variability and erosivity in subhumid and humid zones of southern Nigeria
Authors: Salako F. K. 
Published: September 2006

AbstractSoil erosion by water is a major cause of land degradation in the tropics. Its quantitative assessment requires evaluation of factors such as rainfall variability and erosivity. Therefore, pluviograph data from 1977 to 1999 for the subhumid (Ibadan) and humid forest (Port‐Harcourt) zones of southern Nigeria were analysed to determine the temporal and spatial variability of rainfall erosivity. Analyses were carried out generally at 15‐minute intervals to obtain rainfall amount, duration, intensity and kinetic energy. Descriptive statistics and t‐tests were used for data analyses. Rainfall intensities between 100 and 150 mm h−1 occurred every year. Rainfall intensities were higher in the subhumid (SH) than humid forest (HF) zone whereas the kinetic energy of rainfall was higher in the HF than the SH zone. Thus, the high erosivity in the SH was mainly due to high intensities whereas it was mainly due to high amounts in the HF zone. In both zones, 42 per cent of the years exceeded long‐term annual average of erosivity. The mean annual EI30 was 11 107 MJ mm ha−1 h−1 in the SH zone and 17 988 MJ mm ha−1 h−1 for the HF zone. Rainfall erosivity indices (E and EI30) correlated significantly with rainfall amount, with 86–99 per cent of variations in daily erosivity explained, and 55–99 per cent of variations in annual erosivity explained by rainfall amount. Spatial and temporal variations were not only influenced by rainfall characteristics but also by inherent differences in rainfall erosivity indices. The data presented are required in the prevention or control of land degradation as well as in the development of watersheds, particularly in the tropics. Copyright © 2006 John Wiley & Sons, Ltd.
Electroactive Copolymers with Oligoanilines in the Main Chain via Oxidative Coupling Polymerization
Authors: Chao Danming , Cui Lili , Li Zhicheng , Lu Xiaofeng , Mao Hui , Zhang Wanjin , Wei Yen 
Published: September 2006

AbstractSummary: By oxidative coupling polymerization of the macromonomer of oligoaniline and p‐phenylenediamine, we have prepared an electroactive copolymer, exhibiting an exciting molecular structure, and interesting spectroscopic and electrochemical properties. The polymerization characteristics and structure of the copolymer were systematically studied by gel permeation chromatography (GPC), Fourier‐transform infrared (FTIR) spectroscopy, 1H NMR spectroscopy and X‐ray powder diffraction (XRD). UV‐vis spectra were used to monitor the chemical oxidation process of the reduced copolymer. The electrochemical activity of the copolymer was tested in 1.0 M H2SO4 aqueous solution. Three redox peaks were shown, which is different to that for polyaniline. The thermal properties of the copolymer were also evaluated, by thermogravimetric analysis (TGA); the electrical conductivity is about 5.53 × 10−5 Scm−1 at room temperature, upon a preliminarily, proton‐doped experiment.Synthesis of the copolymer.magnified imageSynthesis of the copolymer.