bluuebunny/crossref_metadata_2025 huggingface dataset:
Ozone variability and halogen oxidation within the Arctic and sub-Arctic springtime boundary layer
Authors: Gilman J. B. , Burkhart J. F. , Lerner B. M. , Williams E. J. , Kuster W. C. , Goldan P. D. , Murphy P. C. , Warneke C. , Fowler C. , Montzka S. A. , Miller B. R. , Miller L. , Oltmans S. J. , Ryerson T. B. , Cooper O. R. , Stohl A. , de Gouw J. A.
Published: November 2010

Abstract. The influence of halogen oxidation on the variabilities of ozone (O3) and volatile organic compounds (VOCs) within the Arctic and sub-Arctic atmospheric boundary layer was investigated using field measurements from multiple campaigns conducted in March and April 2008 as part of the POLARCAT project. For the ship-based measurements, a high degree of correlation (r = 0.98 for 544 data points collected north of 68° N) was observed between the acetylene to benzene ratio, used as a marker for chlorine and bromine oxidation, and O3 signifying the vast influence of halogen oxidation throughout the ice-free regions of the North Atlantic. Concurrent airborne and ground-based measurements in the Alaskan Arctic substantiated this correlation and were used to demonstrate that halogen oxidation influenced O3 variability throughout the Arctic boundary layer during these springtime studies. Measurements aboard the R/V Knorr in the North Atlantic and Arctic Oceans provided a unique view of the transport of O3-poor air masses from the Arctic Basin to latitudes as far south as 52° N. FLEXPART, a Lagrangian transport model, was used to quantitatively determine the exposure of air masses encountered by the ship to first-year ice (FYI), multi-year ice (MYI), and total ICE (FYI+MYI). O3 anti-correlated with the modeled total ICE tracer (r = −0.86) indicating that up to 73% of the O3 variability measured in the Arctic marine boundary layer could be related to sea ice exposure.
Global retrieval of ATSR cloud parameters and evaluation (GRAPE): dataset assessment
Authors: Sayer A. M. , Poulsen C. A. , Arnold C. , Campmany E. , Dean S. , Ewen G. B. L. , Grainger R. G. , Lawrence B. N. , Siddans R. , Thomas G. E. , Watts P. D.
Published: November 2010

Abstract. The Along-Track Scanning Radiometers (ATSRs) provide a long time-series of measurements suitable for the retrieval of cloud properties. This work evaluates the freely-available Global Retrieval of ATSR Cloud Parameters and Evaluation (GRAPE) dataset (version 3) created from the ATSR-2 (1995–2003) and Advanced ATSR (AATSR; 2002 onwards) records. Users are recommended to consider only retrievals flagged as high-quality, where there is a good consistency between the measurements and the retrieved state (corresponding to about 60% of converged retrievals over sea, and more than 80% over land). Cloud properties are found to be generally free of any significant spurious trends relating to satellite zenith angle. Estimates of the random error on retrieved cloud properties are suggested to be generally appropriate for optically-thick clouds, and up to a factor of two too small for optically-thin cases. The correspondence between ATSR-2 and AATSR cloud properties is high, but a relative calibration difference between the sensors of order 5–10% at 660 nm and 870 nm limits the potential of the current version of the dataset for trend analysis. As ATSR-2 is thought to have the better absolute calibration, the discussion focusses on this portion of the record. Cloud-top heights from GRAPE compare well to ground-based data at four sites, particularly for shallow clouds. Clouds forming in boundary-layer inversions are typically around 1 km too high in GRAPE due to poorly-resolved inversions in the modelled temperature profiles used. Global cloud fields are compared to satellite products derived from the Moderate Resolution Imaging Spectroradiometer (MODIS), Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) measurements, and a climatology of liquid water content derived from satellite microwave radiometers. In all cases the main reasons for differences are linked to differing sensitivity to, and treatment of, multi-layer cloud systems. The correlation coefficient between GRAPE and the two MODIS products considered is generally high (greater than 0.7 for most cloud properties), except for liquid and ice cloud effective radius, which also show biases between the datasets. For liquid clouds, part of the difference is linked to choice of wavelengths used in the retrieval. Total cloud cover is slightly lower in GRAPE (0.64) than the CALIOP dataset (0.66). GRAPE underestimates liquid cloud water path relative to microwave radiometers by up to 100 g m−2 near the Equator and overestimates by around 50 g m−2 in the storm tracks. Finally, potential future improvements to the algorithm are outlined.
Global distribution of sea salt aerosols: new constraints from in situ and remote sensing observations
Authors: Jaeglé L. , Quinn P. K. , Bates T. , Alexander B. , Lin J.-T.
Published: November 2010

Abstract. We combine in situ measurements of sea salt aerosols (SSA) from open ocean cruises and ground-based stations together with aerosol optical depth (AOD) observations from MODIS and AERONET, and the GEOS-Chem global chemical transport model to provide new constraints on SSA emissions over the world's oceans. We find that the GEOS-Chem model using the Gong (2003) SSA source function overestimates cruise observations of coarse mode SSA mass concentrations by factors of 2–3 at high wind speeds over the cold waters of the Southern Ocean and North Atlantic. Furthermore, the model systematically underestimates SSA over the warm tropical waters of the Central Pacific, Atlantic, and Indian Oceans. This pattern is confirmed by SSA measurements from a global network of 15 island and coastal stations. The model discrepancy at high wind speeds (>6 m s−1) has a clear dependence on sea surface temperature (SST). We use the cruise observations to derive an empirical SSA source function depending on both wind speed and SST. Implementing this new source function in GEOS-Chem results in improved agreement with in situ observations, with a decrease in the model bias from +64% to +33% for the cruises and from +32% to −5% for the ground-based sites. We also show that the wind speed-SST source function significantly improves agreement with MODIS and AERONET AOD, and provides an explanation for the high AOD observed over the tropical oceans. With the wind speed-SST formulation, global SSA emissions show a small decrease from 5212 Mg/year to 4545 Mg/yr, while the SSA burden decreases from 9.1 to 8.5 mg/m2. The spatial distribution of SSA, however, is greatly affected, with the SSA burden increasing by 50% in the tropics and decreasing by 40% at mid- and high-latitudes. Our results imply a stronger than expected halogen source from SSA in the tropical marine boundary layer. They also imply stronger radiative forcing of SSA in the tropics and a larger response of SSA emissions to climate change than previously believed.
Estimating the atmospheric boundary layer height over sloped, forested terrain from surface spectral analysis during BEARPEX
Authors: Choi W. , Faloona I. C. , McKay M. , Goldstein A. H. , Baker B.
Published: November 2010

Abstract. In this study the atmospheric boundary layer (ABL) height (zi) over complex, forested terrain is estimated based on the power spectra and the integral length scale of horizontal winds obtained from a three-axis sonic anemometer during the BEARPEX (Biosphere Effects on Aerosol and Photochemistry) Experiment. The zi values estimated with this technique showed very good agreement with observations obtained from balloon tether sonde (2007) and rawinsonde (2009) measurements under unstable conditions (z/L < 0) at the coniferous forest in the California Sierra Nevada. The behavior of the nocturnal boundary layer height (h) and power spectra of lateral winds and temperature under stable conditions (z/L > 0) is also presented. The nocturnal boundary layer height is found to be fairly well predicted by a recent interpolation formula proposed by Zilitinkevich et al. (2007), although it was observed to only vary from 60–80 m during the experiment. Finally, significant directional wind shear was observed during both day and night with winds backing from the prevailing west-southwesterlies in the ABL (anabatic cross-valley circulation) to consistent southerlies in a layer ~1 km thick just above the ABL before veering to the prevailing westerlies further aloft. We show that this is consistent with the forcing of a thermal wind driven by the regional temperature gradient directed due east in the lower troposphere.
Effect of permafrost thawing on the organic carbon and trace element colloidal speciation and microbial activity in thermokarst lakes of Western Siberia
Authors: Pokrovsky O. S. , Shirokova L. S. , Kirpotin S. N. , Audry S. , Viers J. , Dupre B.
Published: November 2010

Abstract. In order to understand the mechanisms of carbon mobilization and biodegradation during permafrost thawing and to establish the link between the organic carbon (OC), and other chemical and microbiological parameters in forming thermokarstic (thaw) lakes, we studied biogeochemistry of OC and trace elements (TE) in a chronosequence of small lakes that are being formed due to permafrost thawing in the northern part of Western Siberia. About 20 lakes and small ponds of various sizes and ages were sampled for dissolved and colloidal organic carbon and metals and culturable heterotrophic bacterial cell number. We observed a sequence of ecosystem stages corresponding to the evolution from peat thawing and palsa degradation due to permafrost subsidence in small ponds to large, km – size lakes subject to drainage and, finally, the khasyrey (drained lake) formation. There is a systematic evolution of both total dissolved and colloidal concentration of OC and TE in the lake water along the chronosequence of lake development that may be directly linked to microbial mineralization of dissolved organic matter and liberation of the mineral part (Fe, Al, TE) from organo-mineral colloids. In this chronosequence of lake development, we observe a clear decrease of the relative proportion of <1 kDa (1 kDa~1 nm) OC concentration along with concentration of total dissolved (<0.45 μm) OC. This is accompanied by an increase of the small size organic ligands (probably autochtonous exometabolites produced by the phytoplankton) and a concomitant decrease of the proportion of large-size organic (humic) complexes having allochtonous (soil) origin. This evolution may be due to the activity of heterotrophic bacterioplancton that uses allochtonous organic matter and dissolved nutrients originated from the peat lixiviation. Most insoluble TE demonstrate a systematic decrease of concentration during filtration (5 μm, 0.45 μm) exhibiting a similar pattern among different samples. At the same time, there is an increase of the relative proportion of large size particles over <1 kDa fraction for most insoluble elements along the chronosequence of lake evolution. TE are likely to be bound to colloidal OC but also coprecipitated with the mineral (Fe, Al) part of colloids. Upon progressive consumption of dissolved OC by heterotrophic bacteria, there is a liberation of Fe, Al, and insoluble TE in the water column that may be subjected to coagulation in the form of particles or large-size mineral colloids.
Convex and concave types of second baroclinic mode internal solitary waves
Authors: Yang Y. J. , Fang Y. C. , Tang T. Y. , Ramp S. R.
Published: November 2010

Abstract. Two types of second baroclinic mode (mode-2) internal solitary waves (ISWs) were found on the continental slope of the northern South China Sea. The convex waveform displaced the thermal structure upward in the upper layer and downward in the lower layer, causing a bulge in the thermocline. The concave waveform did the opposite, causing a constriction. A few concave waves were observed in the South China Sea, marking the first documentation of such waves. On the basis of the Korteweg-de Vries (K-dV) equation, an analytical three-layer ocean model was used to study the characteristics of the two mode-2 ISW types. The analytical solution was primarily a function of the thickness of each layer and the density difference between the layers. Middle-layer thickness plays a key role in the resulting mode-2 ISW. A convex wave was generated when the middle-layer thickness was relatively thinner than the upper and lower layers, whereas only a concave wave could be produced when the middle-layer thickness was greater than half the water depth. In accordance with the K-dV equation, a positive and negative quadratic nonlinearity coefficient, α2, which is primarily dominated by the middle-layer thickness, resulted in convex and concave waves, respectively. The analytical solution showed that the wave propagation of a convex (concave) wave has the same direction as the current velocity in the middle (upper or lower) layer. Analysis of the three-layer ocean model properly reproduced the characteristics of the observed mode-2 ISWs in the South China Sea and provided a criterion for the existence of convex or concave waves. Concave waves were seldom seen because of the rarity of a stratified ocean with a thick middle layer. This analytical result agreed well with the observations.
Modeling the Effect of Heating Rate on Recrystallization Texture Evolution in AA3103
Authors: Schäfer Carmen , Mohles Volker , Gottstein Günter
Published: November 2010

The advanced 3D cellular automata model CORe was utilized to model recrystallization texture development, i.e., under the impact of a change of the solute concentration and the size and volume fraction of precipitates. For consideration of the changes in microchemistry, the model was sequentially coupled to the precipitation model ClaNG. A decrease in the average stored dislocation density within the deformed grains owing to recovery was also taken into account. The model was applied to the prediction of recrystallization texture during annealing with various heating rates, which influence the constitution of the material. The simulation results were compared to texture measurements.
The Effect of Intermediate Annealing on Texture Banding in Aluminum Alloy 6016
Authors: Bennett Tricia A. , Sidor Jurij , Petrov Roumen H. , Kestens Leo A. I.
Published: November 2010

The roping phenomenon was investigated in two alloys of 6016 aluminum. In one case the material (GR) is more resistant to roping. In the other (BR), the material is less resistant to roping. Roping lines are therefore more pronounced in the BR material compared to the GR case. One significant difference between the processing of these materials is that the GR material underwent intermediate annealing (IA); the BR material did not. Through‐process characterization of the BR and GR materials by electron backscatter diffraction (EBSD) revealed that the IA step transformed the texture of the GR material compared to the BR case, where the evolution was typical of Al alloys. It was found that the IA step set the stage for the ensuing differences in texture evolution, spatial distribution of {1 0 0} ⟨0 0 1〉 Cube grains and ultimately, the different roping behaviors exhibited by the BR and GR materials.
Influence of Crystallography on Shear‐Band Formation in FCC Metals
Authors: Jasieński Zdzistaw , Piątkowski Andrzej
Published: November 2010

The localization of plastic deformation in the form of macroscopic shear bands (MSBs) is a typical phenomenon in FCC metals at large strains. To confirm the hypothesis of the crystallographic character of an MSB (the occurrence of shear inside an MSB along the {111} slip and twinning phases), the microstructure, local orientation and misorientation inside a single band are examined. A study of the texture and microstructure evolution after a change of deformation path in channel‐die‐compressed (1 1 2)[1 1 −1] planes single crystals of copper confirms the influence of the single‐crystal orientation of on MSB formation. The specific coplanar configuration of two active slip systems favors MSB development.
Spark Plasma Sintered Hydroxyapatite/Multiwalled Carbon Nanotube Composites With Preferred Crystal Orientation
Authors: Zhu Jiangtao , Tjong Sie Chin , Li Xiao‐Qiang
Published: November 2010

Hydroxyapatite (HA) and its nanocomposites reinforced with low loading levels of multiwalled carbon nanotubes (MWNTs) are prepared by spark plasma sintering process. The structure, morphology, and hardness of sintered HA and MWNT/HA nanocomposites are characterized by means of X‐ray diffraction (XRD), scanning electron microscopy and nanoindentation techniques. XRD results show that the orientation of crystallographic planes of sintered HA are highly related to the applied pressure direction. The perpendicular section of sintered MWNT/HA nanocomposites shows predominantly oriented HA a‐and b‐planes while the parallel section displays a dominant c‐plane orientation. The hardness of MWNT/HA nanocomposites improves considerably with increasing MWNT content.
Fuel Cells: Structure‐Morphology‐Property Relationships of Non‐Perfluorinated Proton‐Conducting Membranes (Adv. Mater. 42/2010)
Authors: Peckham Timothy J. , Holdcroft Steven
Published: November 2010

A fundamental understanding of structure‐morphology‐property relationships of proton exchange membranes (PEMs) is crucial in order to improve the cost, performance, and durability of PEM fuel cells (PEMFCs). In this context, there has been an explosion over the past five years in the volume of research carried out in the area of non‐perfluorinated, proton‐conducting polymer membranes, with a particular emphasis on exploiting phase behavior associated with block and graft copolymers. This progress report highlights a selection of interesting studies in the area that have appeared since 2005, which illustrate the effects of factors such as acid and water contents and morphology upon proton conduction. It concludes with an outlook on future directions.
Viscous quark‐gluon plasma in the early universe
Authors: Tawfik A. , Wahba M. , Mansour H. , Harko T.
Published: November 2010

In the present work a study is given for the evolution of a flat, isotropic and homogeneous Universe, which is filled with a causal bulk viscous cosmological fluid. We describe the viscous properties by an ultra‐relativistic equation of state, and bulk viscosity coefficient obtained from recent lattice QCD calculations. The basic equation for the Hubble parameter is derived by using the energy equation obtained from the assumption of the covariant conservation of the energy‐momentum tensor of the matter in the Universe. By assuming a power law dependence of the bulk viscosity coefficient, temperature and relaxation time on the energy density, we derive the evolution equation for the Hubble function. By using the equations of state from recent lattice QCD simulations and heavy‐ion collisions we obtain an approximate solution of the field equations. In this treatment for the viscous cosmology, no evidence for singularity is observed. For example, both the Hubble parameter and the scale factor are finite at t = 0, where t is the comoving time. Furthermore, their time evolution essentially differs from the one associated with non‐viscous and ideal gas. Also it is noticed that the thermodynamic quantities, like temperature, energy density and bulk pressure remain finite. Particular solutions are also considered in order to prove that the free parameter in this model does qualitatively influence the final results.
The scientific road of Manuel Cardona: a bibliometric analysis
Authors: Romero A.H. , Kremer R.K. , Marx W.
Published: November 2010

We present a detailed bibliometric analysis of the scientific contributions of Manuel Cardona, who represents an interesting example of a renowned scientist with a long and fruitful career. His publications provide an appropriate basis to apply various bibliometric techniques to measure the impact of his scientific achievements. For this purpose, we have taken into account his full publication record, the institutions of all his coauthors, the journals where his papers have been published, and the citations of his papers as a measure of their impact. We have analyzed in more detail some of his most important publications, which appeared as journal papers and book contributions. Additionally, we have broken down the complete ensemble of the citing papers with respect to the countries of authors, the journals, and the subject areas. The analysis performed in this study also makes use of the Hirsch index as one of the most recognized bibliometric indicators which has rapidly captured the field of research evaluation. Finally, we have established the citation historiogram based on the most highly‐cited papers to visualize their citation network.
Enacting national concerns: Anglo‐British accounts of the 2002 Royal Golden Jubilee
Authors: Stevenson Clifford , Abell Jackie
Published: November 2010

Although the study of national identity in social psychology has examined the various ways in which the national group is ‘imagined’, little attention has been paid to the many collective national commemorations, celebrations and rituals of state assumed to unite the nation. This is surprising given the number of celebrations and commemorations which fill the calendars of modern nations throughout the world and which are assumed by social scientists to play some part in the reproduction of the national community. Taking the British Royal Golden Jubilee celebrations of 2002, the present study examines how understandings of Anglo‐British national identity are manifest in conversational interviews during and after these events. In line with previous examinations of Anglo‐Britishness, our respondents typically resisted imagining the national community as a homogenous whole and distanced themselves from depictions of the Jubilee as a nationalistic event. Support for the Jubilee was contingent upon the event being apolitical and inclusive. We suggest that such collective national events could potentially facilitate ways of imagining the national community in terms of diversity and inclusivity rather than homogeneity and exclusivity. Copyright © 2010 John Wiley & Sons, Ltd.
Stories as indicators of practical knowledge: Analysing project workers' talk from a study of participation in a youth inclusion programme
Authors: Nolas Sevasti‐Melissa
Published: November 2010

The paper deals with the issue of practical knowledge for enabling participation. Participation as a strategy for change is widespread in community, health and human service contexts. Research to date has focused on the mechanisms of beneficiaries' participation (e.g. identity, empowerment, activity, gender, space). However, participation as an engagement strategy is action oriented and requires high levels of interaction between those creating the conditions for participation and those participating. These conditions need to be continuously adjusted and outcomes are often unpredictable. This process of ‘working with’ is often dealt with as a technical issue and captured in metaphorical language. Less emphasis has been given to the type of knowledge modalities that might be necessary in order to enable participation. Drawing on an ethnographic case study of participation in a youth inclusion programme the paper explores the role of stories as potential indicators of practical knowledge. The paper argues that enabling young people's participation requires intuition and imagination, patience and perseverance, and judgement for acting under uncertainty. It concludes that stories only partially fulfil their potential as indicators of such knowledge modalities. Copyright © 2010 John Wiley & Sons, Ltd.
Feature sensitive deformation for triangular mesh models
Authors: He Jun , Zhang Caiming , Wei Yu , Li Weitao
Published: November 2010

Shape deformation is a useful tool for shape modeling and animation in computer graphics. In this paper, we propose a novel surface deformation method based on a feature sensitive (FS) metric. Firstly, taking unit normal vectors into account, we derive a FS Laplacian operator, which is more sensitive to featured regions of mesh models than existing operators. Secondly, we use the 1‐ring tetrahedron in the dual mesh, a volumetric structure, to encode geometric details. To preserve the shape of the tetrahedron, we introduce linear tetrahedron constraints minimizing both the distortion of the base triangle and the change of the corresponding height. These ensure that geometric details are accurately preserved during deformation. The time complexity of our new method is similar to that of existing linear Laplacian methods. Examples are included to show that our FS deformation method better preserves mesh details, especially features, than existing Laplacian methods. Copyright © 2010 John Wiley & Sons, Ltd.
Application of ESI and MALDI‐TOF MS for triacylglycerols analysis in edible oils
Authors: Cozzolino Rosaria , De Giulio Beatrice
Published: November 2010

Triacylglycerols (TAG) are the most important group of compounds present in vegetable oils. These biomolecules, determining the physical, chemical and nutritional properties of the oils, are considered to be good fingerprints for quality and authenticity control. Therefore, TAGs characterization is a very important task in edible oil field, which has been undertaken by different analytical methods.

The analysis of vegetable oils is still dominated by classic determinations, which are however laborious and time‐consuming and cannot be used routinely. More recently, advances in MS instrumentations coupled with online separation techniques and data processing have contributed to great expansion of MS in oil study, allowing the development of innovative analytical approaches that exhibit higher sensitivity, accuracy and rapidity in vegetable oils investigations.

In the present contribution, a review of the most relevant applications of novel mass spectrometric techniques, such as ESI and MALDI, both alone and hyphenated with HPLC, used for analysis of the complex TAGs mixture of edible oils is illustrated.
Metal‐catalysed isotopic exchange labelling: 30 years of experience in pharmaceutical R&D
Authors: Allen Paul H. , Hickey Michael J. , Kingston Lee P. , Wilkinson David J.
Published: November 2010

Metal‐catalysed exchange has been used extensively in the laboratories of AstraZeneca plc at R&D Charnwood to label a variety of molecules of pharmaceutical interest with the isotopes of deuterium and tritium. Despite early prejudices against the use of tritiated compounds, particularly in ADME studies, the development of directed isotopic exchange techniques has enabled timely and economic support for many pharmaceutical projects. Copyright © 2010 John Wiley & Sons, Ltd.
Efficient syntheses of 13C‐ and 14C‐labelled 5‐benzyl and 5‐indolylmethyl L‐hydantoins
Authors: Patching Simon G.
Published: November 2010

Robust and straightforward methods are described for the first syntheses of highly pure 13C‐ and 14C‐labelled L‐5‐benzylhydantoin (L‐BH) and L‐5‐indolylmethylhydantoin (L‐IMH) by cyclizing the amino acids L‐phenylalanine and L‐tryptophan, respectively, with potassium cyanate. [3‐13C]‐L‐phenylalanine was used to prepare [6‐13C]‐L‐BH and [indole‐2‐13C]‐L‐tryptophan was used to prepare [indole‐2‐13C]‐L‐IMH, which we required for solid‐state NMR experiments with a hydantoin transport protein. The successful incorporation and integrity of the 13C labels was confirmed by solution‐state NMR spectroscopy. [14C]Potassium cyanate was used to prepare [2‐14C]‐L‐BH and [2‐14C]‐L‐IMH, which we required for transport assays with the protein. Copyright © 2010 John Wiley & Sons, Ltd.
N‐heterocyclic carbenes as ligands in palladium‐mediated [11C]radiolabelling of [11C]amides for positron emission tomography
Authors: Jennings Lucy E. , Kealey Steven , Miller Philip W. , Gee Antony D. , Long Nicholas J.
Published: November 2010

A model palladium‐mediated carbonylation reaction synthesizing N‐benzylbenzamide from iodobenzene and benzylamine was used to investigate the potential of four N‐heterocyclic carbenes (N,N′‐bis(diisopropylphenyl)‐4,5‐dihydroimidazolinium chloride (I), N,N′‐bis(1‐mesityl)‐4,5‐dihydroimidazolinium chloride (II), N,N′‐bis(1‐mesityl)imidazolium chloride (III) and N,N′‐bis(1‐adamantyl)imidazolium chloride (IV)) to act as supporting ligands in combination with Pd2(dba)3. Their activities were compared with other Pd‐diphosphine complexes after reaction times of 10 and 120 min. Pd2(dba)3 and III were the best performing after 10 min reaction (20%) and was used to synthesize radiolabelled [11C]N‐benzylbenzamide in good radiochemical yield (55%) and excellent radiochemical purity (99%). A Cu(Tp*) complex was used to trap the typically unreactive and insoluble [11C]CO which was then released and reacted via the Pd‐mediated carbonylation process. Potentially useful side products [11C]N,N′‐dibenzylurea and [11C]benzoic acid were also observed. Increased amounts of [11C]N,N′‐dibenzylurea were yielded when PdCl2 was the Pd precursor. Reduced yields of [11C]benzoic acid and therefore improved RCP were seen for III/Pd2(dba)3 over commonly used dppp/Pd2(dba)3 making it more favourable in this case. Copyright © 2010 John Wiley & Sons, Ltd.
Colour‐based assessment of atmospheric corrosion products, namely of flash rust, on steel
Authors: Momber A.
Published: November 2010

The paper reviews the utilization of colour analyses for the assessment and rating of atmospheric corrosion products, whereas particular attention is spent to flash rusting. The background of flash rust formation is discussed first, along with a brief review about the composition of flash rust. The fundamentals of the HSV colour model, which is selected as a simple suitable model, are introduced. Finally, the author discusses the utilization of the suggested approach for the evaluation of steel substrate cleanliness and rust assessment.
Guideline for an assessment of electrochemical noise measurement devices
Authors: Ritter S. , Huet F. , Cottis R. A.
Published: November 2010

Pro‐active ageing management is becoming more and more important for the economical and safe operation of industrial plants. A key element for a pro‐active ageing management approach is to apply in situ corrosion monitoring. The electrochemical noise (EN) technique is an example of a promising method, especially for monitoring localised corrosion phenomena. Currently, research work on the EN technique is carried out in several laboratories worldwide for different kind of industrial applications but also for the investigation of corrosion mechanisms. A prerequisite for performing serious research on the EN measurement technique is a careful evaluation of the measuring system, even if commercially available EN measurement instruments are used. Therefore, testing on well‐defined dummy cells should always be a preliminary step to assess the baseline noise of the EN measurement equipment and to ensure data validity. For this purpose a guideline has been developed by the European Cooperative Group on Corrosion Monitoring of Nuclear Materials (ECG‐COMON 1) as an outcome from round‐robin testing on EN. The current guideline describes a simple procedure for the performance and evaluation of EN measurement equipment using dummy cells.
An economic view of food deserts in the united states
Authors: Bitler Marianne , Haider Steven J.
Published: November 2010

Considerable policy and academic attention has been focused on the topic of food deserts. We consider this topic from an economic perspective. First, we consider how the components of a standard economic analysis apply to the study of food deserts. Second, using this economic lens, we revisit the empirical literature on food deserts to assess the progress that has been made regarding whether food deserts are problematic in the U.S. Overall, despite several studies documenting the existence of food deserts in local areas, shortcomings in available data have not allowed researchers to convincingly document the presence or absence of food deserts on a national scale, and virtually no research has provided insight as to why food deserts might exist. © 2010 by the Association for Public Policy Analysis and Management.
Chemometric Evaluation of the Anti‐cancer Pro‐drug Podophyllotoxin and Potential Therapeutic Analogues in Juniperus and Podophyllum Species
Authors: Kusari Souvik , Zühlke Sebastian , Spiteller Michael
Published: November 2010

Introduction – Podophyllotoxin, deoxypodophyllotoxin, demethylpodophyllotoxin and podophyllotoxone are four therapeutically potent secondary metabolites. There is a dearth of information on the holistic analysis of their distribution pattern in both phylogenetic and ecological contexts.

Objectives – To analyse the continuum of the above metabolites in Juniperus and Podophyllum species collected from natural populations in Himalayan environments and the botanical gardens of Rombergpark and Haltern (Germany) using multi‐component LC‐ESI‐MS/MS, coupled with statistically relevant chemometric assessment.

Methodology – We evaluated the individual and holistic metabolite profiles and chemometrically correlated the phytochemical loads between various species (infraspecific), organic and aqueous extracts, and populations of the same species from different locations, different species from same location, different species from different locations and infrageneric populations from same and different locations.

Results – Multivariate analysis revealed Juniperus x‐media Pfitzeriana as a suitable alternative to Podophyllum hexandrum for commercial exploitation. A significant positive correlation of podophyllotoxone with both podophyllotoxin and demethylpodophyllotoxin, and a negative correlation of podophyllotoxin with both deoxypodophyllotoxin and demethylpodophyllotoxin (infraspecific among Podophyllum), were observed by Kruskal's multidimensional scaling and corroborated by principal component analysis, indicating probable similarity and/or difference between the biosynthetic pathways, and synergistic and/or antagonistic principles, respectively. Finally, linear discriminant analysis and hierarchical agglomerative cluster analysis revealed considerable infrageneric and infraspecific variability in secondary compound spectra and load of the different populations under study.

Conclusion – Such holistic studies of plants and their therapeutic metabolites ought to assist in selecting plants, geographical areas and environmental conditions for bioprospecting and global‐scale phytochemical and phylogenetic diversity studies in the future. Copyright © 2010 John Wiley & Sons, Ltd.
Structure Characterization and Identification Steroidal Saponins from Ophiopogon Japonicus Ker‐Gawler (Liliaceae) by High‐Performance Liquid Chromatography with Ion Trap Mass Spectrometry
Authors: Wang Yongyi , Xu Jinzhong , Qu Haibin
Published: November 2010

Introduction – Steroidal saponins are the main active constituents in Ophiopogon japonicus Ker‐Gawler (Liliaceae). However, because of their high polarity, non‐chromophores and low content in plants, steroidal saponins are difficult to be isolated from O. japonicus by conventional phytochemical methods.

Objective – To develop a sensitive and rapid approach towards the structural analysis of steroidal saponins using HPLC/ESI‐MSn.

Methodology – The fragmentation behaviors of six known steroidal saponins in negative ESI‐MSn were used to deduce their mass spectral fragmentation mechanisms. By using HPLC/ESI‐MSn, the important structural information on aglycone types, sugar types and saccharide sequences can be obtained.

Results – According to the HPLC retention behaviour, the molecular structural characteristics provided by multistage mass spectrometry spectra and the literature, a total of 8 steroidal saponins were tentatively identified or characterized in O. japonicus rapidly. Conclusion – This work has shown that HPLC‐ESI‐MSn may be used as an effective and rapid method for the characterization and identification of steroidal saponins from O. japonicus. Copyright © 2010 John Wiley & Sons, Ltd.
Optimization of ultrasonic‐stimulated solvent extraction of sinigrin from Indian mustard seed (Brassica JunceaL.) using response surface methodology
Authors: Wang Tianxin , Liang Hao , Yuan Qipeng
Published: November 2010

Introduction – Sinigrin, a major glucosinolate present in Indian mustard (Brassica junceaL.) seeds as the precursor of the anticancer compound allyl isothiocyanate, shows a wide range of biological activities. It's necessary to optimize the extraction methods and conditions, in order to improve the extraction productivity and save raw material.

Objective – To systemically investigate and optimize the most important factors affected the productivity of sinigrin in the process of extraction using response surface methodology.

Methodology – The ranges of three main factors including the ethanol concentration, extraction time and extraction temperature were selected by the one‐factor‐at‐a‐time method. The conditions of ultrasonic‐stimulated extraction of sinigrin from defatted Indian mustard seed powder were optimized by Box‐Behnken design to obtain the maximum productivity.

Result – The predicted productivity (3.81%) was obtained using 57% ethanol concentration at 81°C for 60 min, with the coefficient of the model R2> 0.96 (n = 17). The actual productivity (3.84 ± 0.02%) of sinigrin under the optimized condition was increased by 70.67% compared with the result of conventional extraction. Meanwhile, HPLC, UV and IR were applied to examine if there is a difference between the ultrasonic‐stimulated solvent extraction and conventional extraction, and the improvement of productivity of sinigrin depended on the destruction of cell wall caused by the elimination of outer pectinous material was explained by SEM and composition content analysis.

Conclusion – The ultrasonic‐stimulated solvent extraction was suggested to be a promising method to improve the productivity of sinigrin. And the results demonstrated that sinigrin productivity may be related to pectinous materials existed in the seeds. Copyright © 2010 John Wiley & Sons, Ltd.
Determination and pharmacokinetic study of chiisanogenin in rat plasma by ultra performance liquid chromatography‐tandem mass spectrometry
Authors: Yang Chunjuan , Yu Kai , Song Yang , Qin Feng , Li Famei
Published: November 2010

Introduction – Chiisanogenin existing in many Acanthopanax species has been reported to possess anti‐inflammatory, antibacterial and antiplatelet aggregatory activities.

Objective – To develop and validate a rapid and sensitive ultra performance liquid chromatography‐tandem mass spectrometry method for the determination of chiisanogenin in rat plasma and to investigate its pharmacokinetics after oral administration of chiisanogenin or the extract of Acanthopanax sessiliflorus fruits.

Methodology – The sample pretreatment involved a one‐step extraction of 0.2 mL plasma with diethyl ether. Acetaminophen was used as the internal standard. The separation was carried out on an ACQUITY UPLC™ BEH C18 column with a mobile phase of acetonitrile‐5 mM ammonium acetate (90:10, v/v) at a flow rate of 0.2 mL/min. The detection was performed on a triple quadrupole tandem mass spectrometer by multiple reaction monitoring (MRM) mode via electrospray ionization (ESI) source.

Results – A high sample throughput was achieved with an analysis time of 1.1 min per sample. The calibration curve was linear (r2 ≥ 0.99) over the concentration range of 5–500 ng/mL with a lower limit of quantification (LLOQ) of 5 ng/mL. The intra‐day and inter‐day precision (relative standard deviation, R.S.D.) values were below 11% and the accuracy (relative error, R.E.) was within 8% at all three quality control (QC) levels.

Conclusion – The method was successfully applied to the pharmacokinetic study of chiisanogenin in rat after oral administration of chiisanogenin and the extract of Acanthopanax sessiliflorus fruits. Other constituents in the extract affected the pharmacokinetic behavior of chiisanogenin. Copyright © 2010 John Wiley & Sons, Ltd.
Simultaneous determination of five characteristic stilbene glycosides in root bark of Morus albus L. (Cortex Mori) using high‐performance liquid chromatography
Authors: Piao Shu‐juan , Chen Li‐xia , Kang Ning , Qiu Feng
Published: November 2010

Introduction – Cortex Mori, one of the well‐known traditional Chinese herbal medicines, is derived from the root bark of Morus alba L. according to the China Pharmacopeia. Stilbene glycosides are the main components isolated from aqueous extracts of Morus alba and their content varies depending on where Cortex Mori was collected. We have established a qualitative and quantitative method based on the bioactive stilbene glycosides for control of the quality of Cortex Mori from different sources.

Objective – To develop a high‐performance liquid chromatography coupled with ultraviolet absorption detection for simultaneous quantitative determination of five major characteristic stilbene glycosides in 34 samples of the root bark of Morus alba L. (Cortex Mori) from different sources.

Methodology – The analysis was performed on an ODS column using methanol‐water‐acetic acid (18: 82: 0.1, v/v/v) as the mobile phase and the peaks were monitored at 320 nm.

Results – All calibration curves showed good linearity (r ≥ 0.9991) within test ranges. This method showed good repeatability for the quantification of these five components in Cortex Mori with intra‐ and inter‐day standard deviations less than 2.19% and 1.45%, respectively.

Conclusion – The validated method was successfully applied to quantify the five investigated components, including a pair of cis‐trans‐isomers 1 and 2 and a pair of isomers 4 and 5 in 34 samples of Cortex Mori from different sources. Copyright © 2010 John Wiley & Sons, Ltd.
GC‐MS Analysis of Headspace and Liquid Extracts for Metabolomic Differentiation of Citrus Huanglongbing and Zinc Deficiency in Leaves of ‘Valencia’ Sweet Orange from Commercial Groves
Authors: Cevallos‐Cevallos Juan Manuel , García‐Torres Rosalía , Etxeberria Edgardo , Reyes‐De‐Corcuera José Ignacio
Published: November 2010

Introduction – Citrus Huanglongbing (HLB) is considered the most destructive citrus disease worldwide. Symptoms‐based detection of HLB is difficult due to similarities with zinc deficiency.

Objective – To find metabolic differences between leaves from HLB‐infected, zinc‐deficient, and healthy ‘Valencia’ orange trees by using GC‐MS based metabolomics.

Methodology – Analysis based on GC‐MS methods for untargeted metabolite analysis of citrus leaves was developed and optimized. Sample extracts from healthy, zinc deficient, or HLB‐infected sweet orange leaves were submitted to headspace solid phase micro‐extraction (SPME) and derivatization treatments prior to GC‐MS analysis.

Results – Principal components analysis achieved correct classification of all the derivatized liquid extracts. Analysis of variance revealed 6 possible biomarkers for HLB, of which 5 were identified as proline, β‐elemene, (‐)trans‐ caryophyllene, and α‐humulene. Significant (P < 0.05) differences in oxo‐butanedioic acid, arabitol, and neo‐inositol were exclusively detected in samples from plants with zinc deficiency. Levels of isocaryophyllen, α‐selinene, β‐selinene, and fructose were significantly (P < 0.05) different in healthy leaves only.

Conclusion – Results suggest the potential of using identified HLB biomarkers for rapid differentiation of HLB from zinc deficiency. Copyright © 2010 John Wiley & Sons, Ltd.
Qualitative Analysis and Simultaneous Quantification of Phenolic Compounds in the Aerial Parts of Salvia miltiorrhiza by HPLC‐DAD and ESI/MSn
Authors: Chen Hong , Zhang Qin , Wang Xiaoming , Yang Jie , Wang Qiang
Published: November 2010

Introduction – The increasing demands of roots and rhizomes of Salvia miltiorrhiza almost exhausted the wild Salvia sources in China. However, the content and composition of phenolic acids in the aerial parts of the plant and their potential to be used as a substitute has not been explored.

Objective – To evaluate the potential of the aerial parts of Salvia miltiorrhiza as new natural sources of phenolic acids.

Methodology – HPLC coupled with diode array detection (DAD) and electrospray ionization multistage mass spectrometry (ESI/MSn) has been used for qualitative and quantitative analysis of phenolic compounds.

Results – A total of 38 phenolic compounds were identified or tentatively characterized. A quantitative HPLC‐DAD method allowing the simultaneously quantification of six phenolic acids was optimized and validated for linearity, precision, accuracy, and limits of detection and quantification. Calibration curves showed good linear regression (r2
> 0.9991) within test ranges; the recoveries ranged between 95.64 and 101.67% and the RSDs were less than 3.01%.

Conclusion – The developed methods have been proved to be effective for the identification and quantification of phenolic acids in S. miltiorrhiza. The results obtained suggest that the aerial parts of the plant could be used as an alternative source of sage phenolics. Copyright © 2010 John Wiley & Sons, Ltd.
Comparison of Friction Stir and Gas Tungsten Arc Weldments of Modified 12 wt.% Cr Ferritic Stainless Steel
Authors: Lakshminarayanan A.K. , Balasubramanian V.
Published: November 2010

This paper presents the comparative evaluation of microstructural features and mechanical properties of a friction stir welded (solid‐state) and gas tungsten arc welded (fusion weld) 409 M grade ferritic stainless steel joints. Optical microscopy, microhardness, transverse tensile and impact tests were performed. The coarser ferrite grains in the base material are changed to very fine grains consisting of a duplex structure of ferrite and martensite due to the rapid cooling rate and high strain induced by severe plastic deformation caused by frictional stirring. On the other hand, grain growth was observed in the fusion zone as well as heat affected zone of the gas tungsten arc welded joint resulting in deterioration of mechanical properties.
Oxidation Resistance of α‐Al2O3 infiltrated Open Porous Cellular Iron
Authors: Hajas D.E. , Jiang Y. , Angel S. , Schulze S.L. , Bleck W. , Schneider J.M.
Published: November 2010

Open porous cellular iron exhibits low oxidation resistance which is limiting their use for application at room and elevated temperatures. Here we deposit α‐Al2O3 by Chemical Vapor Infiltration (CVI) to enhance oxidation resistance. The oxidation resistance before and after CVI is investigated by thermo gravimetrical analysis (TGA). The reaction products, surface morphologies and cross sections are investigated by X‐ray diffraction, chemical analysis and electron microscopy. α‐Al2O3 infiltrated cellular iron samples exhibit up to 6 orders of magnitude lower oxidation rate at an oxidation temperature of 600 °C, compared to the unprotected cellular iron. In addition, the infiltrated sample shows good resistance during thermal cycling up to this temperature.