bluuebunny/crossref_metadata_2025_split huggingface dataset:
Raman scattering of nanoporous semiconductors
Authors: Irmer Gert 
Published: April 2007

AbstractThe application of Raman scattering for characterizing porous semiconductors is reviewed. For structural units of only a few nanometers in size, as observed in por‐Si or por‐Ge, phonon confinement effects appear that can be used for size determinations. In polar porous semiconductors, surface‐related phonons (Fröhlich modes) between the TO and LO phonons appear. These surface phonons couple with the plasmons of free charge carriers in the porous medium. Examples are given of porous layers on III–V semiconductors in which Raman scattering is used to study charge carrier depletion. For theoretical treatment, the effective medium theory is used, taking into account the morphology with parallel pores or nanocolumns with radii down to a few tens of nanometers. Copyright © 2007 John Wiley & Sons, Ltd.
Rapid polymer blend imaging with quantitative broadband multiplex CARS microscopy
Authors: von Vacano Bernhard , Meyer Lars , Motzkus Marcus 
Published: April 2007

AbstractBroadband multiplex coherent anti‐Stokes Raman scattering (MCARS) microscopy allows the rapid chemical mapping and molecular imaging of untreated material samples with three‐dimensional sectioning capabilities. It can be realized with a single laser in a simple and robust setup using supercontinuum generation in a microstructured fiber. The successful implementation of a MCARS microscope is discussed in detail, its parameters are characterized, and applications are shown for the identification and mapping of polymer blends. An evolutionary fitting routine is presented, which allows a fully quantitative analysis of the MCARS information resulting in high‐contrast chemical maps. The established setup enables reliable day‐to‐day operation as a valuable tool for rapid material characterization. Copyright © 2007 John Wiley & Sons, Ltd.
New approach to single‐shot CARS thermometry of high‐pressure, high‐temperature hydrocarbon flames
Authors: Fabelinsky V. I. , Smirnov V. V. , Stel'makh O. M. , Vereschagin K. A. , Vereschagin A. K. , Clauss W. , Oschwald M. 
Published: April 2007

AbstractWe demonstrate the feasibility of a proposed new approach to CARS thermometry with simultaneous measurements of the intensities of the hydrogen Q‐branch lines and their linewidths during a single laser shot by means of a spectrograph combined with an interferometer having orthogonal directions of dispersions. This allows correct temperature evaluation that takes into account the directly measured linewidths. The experiments were carried out in a H2:N2 = 1:10 mixture in a heated cell at a temperature of 1050 K. The values of the gas mixture temperature, which were defined from dual‐broad band (DBB) CARS spectra with linewidth corrections in a pressure range of 2–9 MPa, coincide with thermocouple measurements within ∼2%, while without such a correction, the discrepancies increase up to 5%. The proposed approach can be applied to CARS temperature measurements in investigations of H2 and hydrocarbon combustions without the necessity of species concentration measurements and not requiring the knowledge of line‐broadening coefficients. Copyright © 2007 John Wiley & Sons, Ltd.
Adiabatic climbing of vibrational ladders using Raman transitions with chirped pump lasers: effect of higher electronic surfaces and control of the shapes of vibrational wave packets
Authors: Tchitchekova Deyana S. , Chelkowski Szczepan , Bandrauk André D. 
Published: April 2007

AbstractUsing numerical solutions of the time‐dependent Schrödinger equation for the H2 molecule in intense laser fields we calculate the vibrational excitation induced by the Raman chirped adiabatic process (RCAP). We show that adding several higher electronic surfaces to a simple two‐surface model improves the efficiency of the ladder‐climbing process at intensities below the adiabaticity threshold. Furthermore, we show that although using photon energies close to the one‐photon electronic transition frequency allows the use of lower pump and Stokes intensities, in general, this leads to more population transfer to the upper electronic surfaces accompanied by a loss of selectivity in the vibrational excitation on the ground‐state surface. By contrast, considerable dissociation yields can be achieved when higher energy photons are used. We also investigate the structure of time‐dependant vibrational wave packets prepared by RCAP. We find that at specific times the wave packet is very well localised at large inter‐nuclear separations at which ionisation occurs with a probability 3 orders of magnitude larger than at the equilibrium separation. Copyright © 2007 John Wiley & Sons, Ltd.
Self‐assembled monolayers of mercaptosuccinic acid monolayers on silver and gold surfaces designed for protein binding. Part II: vibrational spectroscopy studies on cytochrome c immobilization
Authors: Królikowska Agata , Bukowska Jolanta 
Published: April 2007

AbstractAn attempt has been made for using MSA‐modified electrodes as linkage monolayers for electrostatic and covalent binding of cytochrome c (Cc). For MSA monolayers grown from an aqueous solution on Ag, attachment of Cc in its native state is proved in the case of covalent bonding. Electrostatic immobilization of Cc at pH 7 results in presence of at least some amount of Fe2+ high‐spin configuration and/or Fe3+ oxidation state. Native protein Fe2+ low‐spin state of Cc is observed after applying a negative potential to the Ag electrode. The influence of the solvent used for the preparation of the MSA monolayer and thiol surface coverage of the Ag surface was studied. It was shown that the key factor to obtain the native structure of Cc is the successful blocking of the metal surface by the MSA linking layer. IRRAS measurements of MSA on monocrystalline gold (111) at neutral pH confirm the successful electrostatic Cc immobilization, which preserves the Fe2+ oxidation state of the chromophore on this substrate. Copyright © 2007 John Wiley & Sons, Ltd.
Vibrational spectroscopic study of budesonide
Authors: Ali H. R. H. , Edwards H. G. M. , Kendrick J. , Munshi T. , Scowen I. J. 
Published: April 2007

AbstractThe Raman spectrum of budesonide is reported for the first time, and molecular assignments are proposed on the basis of ab initio BLYP DFT calculations with a 6‐31 G* basis set and vibrational wavenumbers predicted on a quasi‐harmonic approximation. Comparison with previously published infrared data has explained several spectral features, and the relative band intensities in the CO and CC stretching regions are interpreted. The results from this study provide data that can be used for the preparative process monitoring of budesonide, an important steroidal pharmaceutical in various dosage forms, and its interaction with excipients and other components. Copyright © 2007 John Wiley & Sons, Ltd.
Isoflavone profiles, phenol content, and antioxidant activity of soybean seeds as influenced by cultivar and growing location in Ohio
Authors: Riedl Ken M , Lee Jae Hwan , Renita Marjory , St Martin Steven K , Schwartz Steven J , Vodovotz Yael 
Published: April 2007

AbstractIsoflavone levels and isoflavone chemical composition in soybeans vary between planting locations although the exact factors which control isoflavone biosynthesis are unclear. We compared levels of 12 isoflavones in soybean seeds of six cultivars grown in four different locations in Ohio in 2002 as determined by high‐performance liquid chromatography. Antioxidant activity contained in plant‐based foods can improve food oxidative stability and phenolics and isoflavones have proven active in food systems. Radical scavenging activity was assessed using the 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical. Total phenolics (TPCs) were determined by using Folin–Ciocalteu reagent. Total isoflavones (TIs) varied five‐fold (1573–7710 nmol g−1) between seeds from the various location–cultivar combinations. One location (Wooster, Ohio) produced seeds containing half the isoflavones as the other locations tested apparently due to poor growing conditions. The cultivars could be divided into two groups based on TI, one having approximately 50% more isoflavones. Surprisingly, across the entire data set, with increasing TI, the proportion of isoflavones accounted for by the daidzein family increased due primarily to malonyl daidzin. DPPH scavenging did not differ significantly by location or cultivar (P > 0.05) and did not correlate with TPC or TI. Profiling soybean isoflavones could help elucidate how isoflavone biosynthesis is regulated and lead to better disease resistance of soybean crops and soy foods with greater health benefits. Copyright © 2007 Society of Chemical Industry
Physicochemical properties of cassava, potato and jicama starches oxidised with organic acids
Authors: Martínez‐Bustos Fernando , Amaya‐Llano Silvia Lorena , Carbajal‐Arteaga J Antonio , Chang Yoon Kil , Zazueta‐Morales José de J 
Published: April 2007

AbstractThe oxidising effects of organic (acetic, citric and lactic) acids on the physicochemical properties of starches from cassava, potato and jicama were investigated. Cassava starch oxidised with lactic and citric acids had the highest carbonyl contents (5.43 and 5.84 g kg−1 respectively), while oxidised potato starch had the highest carboxyl contents. Oxidised jicama starch showed the lowest carbonyl and carboxyl contents. Oxidation increased the maximum viscosity of cassava starch (from 426.61 to 670.11 relative viscosity units (RVU)) and jicama starch (from 160.17 to 561.50 RVU) but decreased that of potato starch (from 669.44 to 206.92 RVU). When carbonyl and carboxyl groups were incorporated into jicama starch granules, the resistance of these granules to stirring at constant temperature (holding) increased, as did their final and retrogradation viscosities. However, the behaviour of oxidised cassava and potato starches, as indicated by a Rapid Visco Analyser, was different. The highest values of endotherm enlargement were found for native and oxidised jicama starch, while the lowest values were found for native and oxidised cassava starch. Native and oxidised potato starch had the highest enthalpy values (14.30–18.30 J g−1), while jicama starch had the lowest (9.50–11.9 J g−1). The high intrinsic viscosity of native potato starch was attributed to B‐type starch with a longer‐than‐average amylopectin chain length and a lower degree of crystallinity. Oxidised granules showed little erosion in the form of grooves; on the contrary, oxidation left the grains with a very smooth surface. Copyright © 2007 Society of Chemical Industry
Diminution of quinolizidine alkaloids, oligosaccharides and phenolic compounds from two species of Lupinus and soybean seeds by the effect of Rhizopus oligosporus
Authors: Jiménez‐Martínez Cristian , Hernández‐Sánchez Humberto , Dávila‐Ortiz Gloria 
Published: April 2007

AbstractLupinus, like Glycine max (soybean), is an ancient leguminous plant. It has been used as a food by people living around the Mediterranean Sea and in the Andean Highlands. This legume contains quinolizidine alkaloids (Qas), oligosaccharides (OGS) and phenolic compounds (PC). The objective of this study was to evaluate the effect of the growth of Rhizopus oligosporus on the levels of Qas, OGS and PC from L. mutabilis, L. campestris and G. max through tempeh elaboration. The results showed that the soaking and cooking processes of legume seeds diminished the Qas content of L. mutabilis and L. campestris by 50%, and after 48 h of fermentation these compounds decreased by more than 90% in total. OGS diminished by more than 90% in the lupin seeds. The PC content of the three seed species subjected to these processes increased their absorbance value, probably due to the enzymatic action of a fungal tannase. These results suggested that the L. mutabilis, L. campestris and G. max fermentation with R. oligosporus is an efficient method for diminishing antinutritional factors and for obtaining a product with optimal nutritional value. Copyright © 2007 Society of Chemical Industry
Phosphorus characterization in feces from broiler chicks fed low‐phytate barley diets
Authors: Leytem April B , Thacker Phil A , Turner Benjamin L 
Published: April 2007

AbstractThe inclusion of low phytate grains in poultry diets can reduce the phosphorus (P) content of poultry feces, but their influence on fecal P composition is not well established. To assess this, 100 male broiler chicks (21 days old) were fed dietary treatments based on either a wild‐type barley or one of three low phytate mutant barleys with 59, 62 and 99% reductions in phytate P, compared with the normal barley diet. The birds were housed in raised‐floor battery cages with mesh grate floors above fecal collection trays with five birds per pen and five pens per treatment. The birds were fed for 9 days and feces were collected twice a day during the last 2 days of the experiment. Total P concentrations were 14–24% lower in feces from birds fed low phytate barley diets compared with those fed the normal barley diet. Phosphorus digestibility increased (P < 0.05) as phytate in the barley diet decreased. Phosphate was the major P fraction in the feces (69–75% extracted P) regardless of the type of barley fed. Phytate constituted only 3–12% of the P in the feces, indicating its hydrolysis in the bird. Overall, these results suggest that feeding low‐phytate barley diets can reduce P concentrations in poultry feces without causing significant changes in P composition. Copyright © 2007 Society of Chemical Industry
Brachypodium: a new monocot model plant system emerges
Authors: Garvin David F 
Published: April 2007

AbstractThe small grass species Brachypodium distachyon (purple false brome) is potentially an ideal model plant system for grass crop research. To realise this potential, a range of genetic and genomic resources have been developed in a very short period of time, and more still are in the pipeline. David Garvin explains how these resources will establish B. distachyon as the newest model plant system and will fill a long‐empty void in genomics resources for grass crop improvement. Copyright © 2007 Society of Chemical Industry
Flavour and aroma of fresh basil are affected by temperature
Authors: Chang Xianmin , Alderson Peter G , Hollowood Tracey A , Hewson Louise , Wright Carles J 
Published: April 2007

AbstractSweet basil (Ocimum basilicum L.) plants at the three‐leaf‐pair growth stage were grown in controlled environment rooms at 15 and 25 °C for 2 weeks. Analysis of volatiles from blended leaves by gas chromatography/mass spectrometry showed that the plants grown at 25 °C contained significantly more volatile oils than those grown at 15 °C. The total volatile oil content in fresh leaves was enhanced by 70%. Temperature also affected the composition of volatile oils. At 25 °C there was an accumulation of eugenol, which contributes to the characteristic taste of basil. Although there was no effect on the relative contents of linalool and 1,8‐cineole, the absolute contents in fresh leaves were significantly different. Sensory analysis showed that 18 out of 21 trained sensory panellists perceived different intensities of volatile oils in fresh basil leaves from the two sources of plants. In addition, a simple consumer preference test conducted with basil users showed a significant preference for the stronger intensity (41 out of 64 consumers). Copyright © 2007 Society of Chemical Industry
Nutritional value of diets containing graded levels of wheat distillers grains with solubles fed to broiler chicks
Authors: Thacker Philip A , Widyaratne Gemunu P 
Published: April 2007

AbstractThis feeding trial was conducted to determine the effects of graded levels of wheat distillers dried grains with solubles (DDGS) on nutrient digestibility and performance when fed to broiler chicks. A total of 125, day‐old, male broiler chicks (52.8 ± 0.6 g) were fed wheat/soybean meal‐based diets containing 0, 5, 10, 15 or 20% wheat DDGS. There were five birds per pen and five replicate pens per treatment. Digestibility coefficients for dry matter (P = 0.001), energy (P = 0.001) and phosphorus (P = 0.001) declined in a linear manner with increasing levels of wheat DDGS in the diet. Despite the lower digestibility of nutrients in diets containing wheat DDGS, there were no significant differences in weight gain (P = 0.721), feed intake (P = 0.748) or feed conversion (P = 0.766) due to the incorporation of wheat DDGS in the diet, although weight gain and feed conversion showed a tendency to decline at the highest inclusion level (20%) in the diet. The overall results of this study indicate that wheat DDGS can be successfully incorporated into diets fed to broiler chicks. Potential detrimental factors contained in wheat DDGS, including a low energy and low lysine content, can be compensated for in diet formulation. Therefore, when the price of alternative feed ingredients dictates, wheat DDGS can be incorporated into diets at levels as high as 15% without detrimental effects on broiler performance. Copyright © 2007 Society of Chemical Industry
Preparative isolation and purification of flavone compounds from Sophora japonica L. by high‐speed counter‐current chromatography combined with macroporous resin column separation
Authors: Sun Ailing , Sun Qinghua , Liu Renmin 
Published: April 2007

AbstractHigh‐speed counter‐current chromatography combined with macroporous resin column separation was applied to the isolation and purification of genistein‐7,4′‐di‐O‐β‐D‐glucoside (I), genistein‐7‐O‐β‐D‐glucopyranoside‐4′‐O‐[(α‐L‐rhamnopyransoyl)‐(1‐2)‐β‐D‐glucopyranoside] (II), kaempferol‐3‐O‐β‐D‐sophoroside(III), quercetin‐3‐O‐β‐L‐ramnopyranosyl‐(1–6)‐β‐D‐glucopyranoside (IV), genistein‐4′‐β‐L‐rhamnopyransoyl‐(1–2)‐α‐D‐glucopyranoside (V), and kaempferol‐3‐O‐β‐L‐ramnopyranosyl‐(1–6)‐β‐D‐glucopyranoside (VI) from the Chinese medicinal herb Sophora japonica L. The crude extracts from the pericarps of Sophora japonica L. were pre‐separated on a D‐101 macroporous resin column and divided into two parts as sample 1 and sample 2. An 80‐mg portion of sample 1 was separated by using n‐butanol‐acetic acid (1%) (5:5, v/v) as the two‐phase solvent system and yielded 30.1 mg of compound I, 23.3 mg of compound II. A 120‐mg portion of sample 2 was separated by using ethyl acetate‐n‐butanol‐acetic acid (1%) (5:0.8:5, v/v) as the two‐phase solvent system and yielded 5.5 mg of compound III, 31.7 mg of compound IV, 37.4 mg of compound V, and 6.2 mg of compound VI. The purities of compounds I, II, III, IV, V, and VI were 98.7, 98.2, 97.8, 98.5, 99.3, and 98.9%, respectively, as determined by HPLC. The chemical structures of these components were identified by 1H‐NMR and 13C‐NMR.
Potential sources of background contaminants in solid phase extraction and microextraction
Authors: Stiles Robert , Yang Ill , Lippincott Robert Lee , Murphy Eileen , Buckley Brian 
Published: April 2007

AbstractA study to identify the sources of background contamination from SPE, using a C‐18 sorbent, and solid‐phase microextraction (SPME), using a 70 μm carbowax/divinylbenzene (CW/DVB) fiber, was carried out. To determine the source of contamination, each material used in the procedure was isolated and examined for their contribution. The solid‐phase column components examined were: sorbent material and frits, column housings and each solvent used to elute analytes off the column. The components examined in the SPME procedure were: SPME fiber, SPME vials, water (HPLC grade), and salt (sodium chloride) used to increase the ionic strength. The majority of the background contaminants from SPE were found to be from the SPE sorbent material and frits. The class of contaminants extracted during a blank extraction were phthalates and other plasticizers used during the manufacturing process. All had blank levels corresponding to measured concentrations below 2 ng/mL, except for undecane, which had a concentration of 5.4 ng/mL. The most prevalent contaminants in the SPME blank procedure are 1,9‐nonanediol, a mixture of phthalates and highly bis‐substituted phenols. All the concentrations were below 2 ng/mL, with the exception of bis (2‐ethylhexyl) phthalate, which had concentrations ranging from 5 to 20 ng/mL.
Miniaturized asymmetrical flow field‐flow fractionation: Application to biological vesicles
Authors: Oh Sunok , Kang Dukjin , Ahn Sung‐Min , Simpson Richard J. , Lee Bong‐Hee , Moon Myeong Hee 
Published: April 2007

AbstractAsymmetrical flow field‐flow fractionation (AFlFFF) has been carried out in a miniaturized channel by reducing the channel dimensions. Performance of the miniaturized AFlFFF (mAFlFFF) channel was evaluated with standard proteins and polystyrene latex spheres from nanometer to micrometer size. By reducing the channel dimension, proteins or particulate materials can be separated within a few minutes without a significant loss in resolution. The mAFlFFF channel was applied for the separation of exosomes harvested from immortalized human mesenchymal stem cell line. It shows a potential to fractionate exosome vesicles according to sizes which can be useful for proteomic studies in relation to immunotherapeutic applications.
Determination of (E)‐10‐hydroxy‐2‐decenoic acid content in pure royal jelly: A comparison between a new CZE method and HPLC
Authors: Ferioli Federico , Marcazzan Gian Luigi , Caboni Maria Fiorenza 
Published: April 2007

AbstractA new CZE method was developed and compared with HPLC for the determination of (E)‐10‐hydroxy‐2‐decenoic acid (10‐HDA) in royal jelly (RJ) samples of different geographical origin. The results obtained with the CZE method were highly correlated with those of HPLC (p <0.01). Under optimized conditions, CZE employed minimal amounts of 50 mM tetraborate buffer as BGE, without the addition of organic solvents, EOF or pH modifiers. The CZE method showed a wide linear response range (0.006–0.808 mg 10‐HDA/mL), a good sensitivity (LOD and LOQ were 0.002 and 0.004 mg/mL, respectively) and a satisfactory instrumental repeatability with respect to migration time and peak area (RSD% less than 1.0 and 2.0% on migration time for intra‐ and interday assay, respectively and less than 2.0 and for 4.0% on peak area for intra‐ and interday assay, respectively). The 10‐HDA content in RJ ranged from 0.8 to 3.2 g/100 g of RJ and a significant difference (p <0.05) was found between the Italian and extra‐European average values: 2.5 and 1.6 g/100 g of RJ, respectively, according to the CZE data. The possibility of application of CZE for routine analyses on RJ and RJ based products to verify their authenticity is highlighted here.
Preparation and chiral recognition ability of crosslinked beads of polysaccharide derivatives
Authors: Ikai Tomoyuki , Yamamoto Chiyo , Kamigaito Masami , Okamoto Yoshio 
Published: April 2007

AbstractThe spherical beads consisting of cellulose 3,5‐dimethylphenylcarbamate with partial hydroxyl groups were prepared to be used as chiral packing materials (CPMs) for HPLC. The beads were obtained without using macroporous silica gel, which is usually used as the support of the CPMs based on the polysaccharide derivatives. After the crosslinking in the bead with diisocyanates, such as 4,4′‐diphenylmethane diisocyanate (MDI), 4,4′‐dibenzyl diisocyanate (DBDI), tolylene‐2,4‐diisocyanate (TDI), and m‐xylylene diisocyanate (XDI), the obtained beads were packed into an HPLC column. As the content of the hydroxyl groups of the cellulose derivatives decreased, the obtained CPM exhibited a higher chiral recognition ability. The beads possessed a higher loading capacity than the CPM prepared by coating the cellulose derivative on silica gel. The crosslinked beads could be used with the eluent containing chloroform. The amylose derivative beads were also prepared as a CPM for chiral HPLC.