bluuebunny/crossref_metadata_2025 huggingface dataset:
The analytical chemistry laboratory at the geophysics institute, Unam, Mexico
Authors: Armienta M A
Published: November 2013

The purpose of this work is to describe the stages, difficulties, and methodology in the establishment of a chemical laboratory for the analyses of geological materials (rocks and groundwaters) at the Geophysics Institute (UNAM, Mexico). Starting from a basic
laboratory substructure consisting basically of one colorimeter, one potentiometer, glassware, reagents, and one furnace, the objective was to implement a laboratory capable of obtaining good quality analyses with minimum expense. The results had to be adequate for use in the study of rock
geochemistry, hydrogeochemistry, and quality of groundwaters. The project is being developed in two stages. The first one is directed towards the quantification of major oxides in rocks and physicochemical parameters in waters. For that purpose, wet methods were developed using the existing
equipment as well as one flame photometer, ion selective electrodes, and one oven. The methodology was based mainly on the "rapid methods" of rock analyses described by Riley (1958), and on the "Standard Methods for the Examination of Water and Wastewater" from APHA. For rock analysis, special
attention was paid to the decomposition procedure to avoid losses of elements, and in the silica and alumina measurement, to achieving good precipitation. A simple device for the FeO determination was developed. The methodology was tested with international standard rock samples. For water analysis,
modifications were carried out mainly in the alkalinity and sulfate determinations. Alkalinity was measured by volumetry using a mixture of bromcresol green and methyl orange as an indicator and heating the sample to expel the CO2 at the end of titration. Sulphates were determined by a modified
turbidimetric technique consisting of weighing exactly the BaCl2 for a better control of the turbidity. The accuracy of the methodology was proven by analysis of the standard mineral water sample of the US EPA. The second stage in the development of the laboratory has consisted of the establishment
of techniques for the quantification of metallic contaminants in waters and trace elements in rocks. These analyses are actually in development using an atomic absorption spectrophotometer and a polarograph recently acquired by the laboratory.
Sampling and data evaluation of 13 rock samples for internal quality control
Authors: Backman C , Liukkonen J
Published: November 2013

The Chemistry Laboratory of the Geological Survey of Finland (GSF) is responsible for the analytical services of the institute. The laboratory also serves customers outside the GSF. Analytical techniques include ICP, XRF, and AAS. For quality assurance purposes,
the laboratory uses internationally certified reference samples, and for several decades has also used its own reference materials. Recently, a project was launched with the purpose of widening the choice of our reference materials and improving the reliability of results through reference to data
from several laboratories. The rock samples selected as reference material are listed in Table 1. Samples of about 300 kg each were collected from homogeneous outcrops and each sample was crushed. About 50 kg of the sample was ground to powder, mixed, and packed into canisters and bottles. These
were distributed to eight laboratories in the Nordic countries. During the project, six more participants joined in. The mean value and coefficient of variation for the results from each laboratory were calculated. Each mean value was then treated as an analytical value, and values of central
interest, such as the median, Gastwirth median, and dominant cluster (DC) mode, were calculated. Graphical presentation was made by means of cumulative frequency diagrams. For elements with more than about ten analytical values, the central values tend to be close together for normally distributed
populations. The DC mode is then proposed as the recommended value. The major components are well represented, but fewer useful analytical values were submitted for trace elements. The reference sample project has provided the laboratory with reference material for the future. Data collection is
still taking place to increase the accuracy of the proposed values for the trace elements. It is emphasized, however, that the purpose of the project is to supplement international reference samples, not to replace them.
Rare-earth element analysis of iron-formation reference samples by inductively coupled plasma mass spectrometry (ICP-MS)
Authors: Balaram V
Published: November 2013

The currently available iron-formation reference samples, namely FER-1, FER-2, FER-3, and FER-4 from CCRMP, and IF-G from GIT-IWG are poorly characterized with respect to the rare-earth element (REE) concentrations. Certified data are not available for the
majority of the REEs. An attempt is made to provide complete REE data on the above five reference samples using ICP-MS. The analytical procedures for the determination of all REEs (La to Lu) in these samples by ICP-MS are described. 115In is used as an internal standard to correct for any drift in
the signal. The operating parameters of the instrument (VG PlasmaQuad) are presented. The matrix and other problems associated with the determination and the accuracies and precisions obtained are discussed. The data obtained are compared with available data in the literature and are found to
compare favourably with the published data. Concentration values have been suggested in cases where certified data are not available.
Determination of Pt, Pd, Rh, and Ru in rocks by NiS fire-assay followed by GF-AAS: instrumental drifts, interferences, and reliability
Authors: Boisvert R , Bergeron M , Turcotte J
Published: November 2013

PGEs (platinum group elements: platinum, palladium, rhodium, ruthenium, iridium, osmium) are commonly determined by nickel sulphide (NiS) fire-assay followed by neutron activation analysis. However, this approach meets serious difficulties with certain types of
rock samples, particularly those rich in As, Sb, and Au, since these elements yield high dead times during counting. In order to avoid these problems we have used NiS fire-assay coupled to graphite furnace atomic absorption spectrometry (GF-AAS) for the measurement of Pt, Pd, Rh, and Ru in rocks. We
have examined: a) furnace operating conditions, b) choice of suitable solvent for analysis, c) possible interferences during GF-AAS analysis, and d) the reliability of the method through measurement of standard reference material SARM-7. Of these four parameters, the possibility of interferences was
primarily investigated. Although numerous analytical procedures have been described in the literature dealing with PGE measurements by NiS fire-assay followed by GF-AAS, very few studies have been conducted on possible interferences between the precious metals themselves as well as those caused by
elements present in the analytical solution (particularly Ni and Fe) and this at PGE concentrations in the order of a few parts per billion. Results indicate that in order to obtain reliable results for Pt, Pd, Rh, and Ru, the furnace must be calibrated using solutions in which Ni concentrations are
similar to those of the samples under analysis. This requires that Ni concentrations in samples be previously measured by flame AAS.
X-ray spectrometric analysis of five Chinese reference samples (GSR 1-5)
Authors: Govil P K
Published: November 2013

Ten major oxides and some selected trace elements: Zr, Y, Sr, Rb, Ba, V, Cr, Ni, Co, Zn, Cu, and Nb have been determined in five Chinese reference samples of granite GSR-1, andesite GSR-2, basalt GSR-3, sandstone GSR-4, and shale GSR-5 using a Philips PW 1400 XRF
spectrometer having an on-line computer and software to correct for matrix effects. Few data are available in the literature on these Chinese standard samples and therefore, an attempt is made to provide usable values. Fused beads using a mixture of lithium tetraborate, lithium metaborate, and
lanthanum oxide in the ratio of 6:3:1 were prepared to determine major oxides. Pressed pellets with the backing of boric acid were used to determine trace elements. The sample pellets were prepared in triplicate and were analyzed ten times for major, minor, and trace elements. XRF data were obtained
with reference to the calibration curves prepared by using a large suite of international reference rock standards. Data on five Chinese standards are reported in this paper along with XRF methodology used for the analysis. The values obtained are in good agreement with the values reported by Xie
and colleagues, the originators of the samples. The exception is for TiO2 in major oxides where values are lower in almost all the standards.
Comparison of the determination of Te by hydride generation ICP-MS and QT-AAS
Authors: Hall G E M , De Silva K N , Gauthier G , MacLaurin A I , Pelchat J C
Published: November 2013

The determination of Te, along with other hydride-forming elements (As, Sb, Se, Bi), has traditionally been carried out at the Geological Survey of Canada by quartz tube atomic absorption spectrometry (QT-AAS). Samples are decomposed by an aqua regia leach or by
the more `total' HF-HClO4-HNO3 digestion in a sealed test-tube. The analytes are separated from possible interferences such as Cu and Ni by precipitation with La(OH)3 and resolubilization in 4M HCl. However, `mutual' interferences in the gas phase, from As especially, remain and degrade the low
level detection of Te. For example, the presence of 1000 ppb in solution of As(V), Se(IV), and Bi(III) suppress the AA signal of 50 ppb Te by 17%, 40%, and 22%, respectively. This presents a major obstacle in ultra-trace analysis for Te in geological materials since its natural abundance
is by far the lowest in this suite of elements (cf. the approximate abundance of Te at 1 ppb in igneous rocks with 2 ppm for As). Arsenic can be preferentially volatilized by evaporation in the presence of Br2/H2SO4 and Se can be reduced to the noninterfering elemental state with KI; however, these
procedures add complexity, time, and room for error in the sample preparation scheme. The work presented here summarizes the preliminary investigation into the capabilities of hydride generation/ICP-MS in the low level detection of Te. This will eventually encompass the determination of all five
hydride-forming elements by ICP-MS following phase-specific or total decompostion procedures.
The present and future of arc source emission spectrometry in China
Authors: Shen R
Published: November 2013

The advantages of arc source emission spectrometry (AS-ES) are discussed in this paper and the intrinsic weakness of AS-ES and limitations of the arc source are reviewed. Some possible approaches for further development of AS-ES by means of theoretical study,
method development, and instrument innovation, etc. are also discussed. The principle characteristic of AS-ES is its high flexibility. This is due to the fractional distillation effect, by which elements of interest in the arc source can be selectively vaporized. The spectrum intensity to background
ratio would be greatly increased by this method; coupled with proper excitation conditions, the detection limits of easily vaporized elements and refractory elements would be effectively lowered, the matrix effect and spectrum interferences could also be minimized. For geological powdered samples,
the detection limits of such easily vaporized elements as Ag, As, Au, B, Bi, Cd, Cu, Ga, Ge, Hg, In, Li, Pb, Rb, Sb, Sn, Te, Tl, Zn, and such refractory elements as Ce, Hf, La, Mo, Nb, Sc, Ta, Th, Ti, V, W, Y, Zr are lower or equal to that of geochemical background values. Therefore, this method is
superior to those such as ICP-ES, AAS, XRF, etc. with the exceptions of As and Hg. The detection limits of those elements with intermediate vaporization temperatures, such as Ba, Be, Co, Cr, Mn, Ni, Sr, and Yb are essentially equal to the methods mentioned above. It should be pointed out that the
stability of the arc discharge itself could be matched to various modern emission sources, but the analytical precision is mainly dependent upon the homogeneity of material to be analyzed entering the source. Therefore, it is still possible to obtain high analytical precision by selecting the proper
analytical conditions. For example, the relative standard deviation (RSD) could be as good as 2% for the major elements in silicate rocks, soils, and refractory metal minerals; for trace elements, an RSD of about 5% is not difficult to achieve. Since AS-ES is capable of determining nearly 40
elements simultaneously, including some important `indicator' elements for geochemical exploration, it should play an important role in analyzing samples collected in large regional reconnaissance programs. Matrix matching should be employed in the selection of calibration standards and accuracy
improved by internal standardization. Currently, studies to improve analysis by AS-ES should focus on: the creation of a stable arc plasma; understanding the functional mechanism of buffer and carrier distillation, and the diffusion mechanism of elements in the electrode; further perfecting some
analytical methods which have already proven its usefulness; exploring the possibility of using multi-internal standardization weighted-compensation method and single-internal standardization coefficient compensation methods; and speeding up the development of computers in acquiring and processing
signals.
Is there an alternative to fire assay for the determination of platinum group elements?
Authors: Totland M , Jarvis I , Jarvis K
Published: November 2013

The platinum group elements (PGEs) Pt, Pd, Ru, Rh, Os, and Ir are found in nature heterogeneously distributed at ultratrace levels. They are, however, of major economic importance, being used as catalysts in the petroleum and chemical industries, as a raw
material in the manufacture of electronic components and jewellery, and as a form of investment. Levels of a few þgþg-1 may be economic to recover, and consequently determinations of sub-ngþg-1 levels are required for geological studies. Recent developments in analytical instrumentation, such as
graphite furnace-atomic absorption spectroscopy, inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and ICP-mass spectroscopy (ICP-MS), have encouraged a reassessment of methods for PGE determination. To analyze at the ultratrace levels present in natural materials, however, usually
requires a preconcentration and/or separation step before final analysis. Traditionally, fire assay has been used to concentrate PGEs in ores, collecting the noble metals in a lead, copper, or nickel sulphide button. This technique requires specialized equipment, large amounts of analytical
reagents, and special procedures to avoid loss of volatile Os and Ru compounds. Additionally, analytical results are highly dependent on the assay conditions. Tellurium collection has also been used to separate and collect the PGEs, although this procedure is lengthy and isotope dilution is
necessary to correct for incomplete co-precipitation. An alternative to Te collection is ion-exchange chromatography. The PGEs readily form anionic chloro-complexes enabling two approaches to ion exchange: (1) an anionic resin can be used and PGE species trapped on the resin, to be subsequently
eluted and analyzed; or (2) a cationic resin can be used to remove the matrix elements, thereby allowing the analysis of concentrated solutions of PGEs. This paper will present results from our research programme which aims to develop simplified procedures for the determination of the PGEs. A
two-step dissolution will be discussed which combines a quick acid attack in sealed microwave vessels, followed by lithium borate fusion of the refractory minerals. Results for two types of ion-exchange resins will be presented (anionic resin, Dowex 1-X8, and cationic resin, Dowex 50W-X8), based on
data obtained by ICP-AES and ICP-MS. Procedures will be evaluated using a range of PGE certified reference materials from South Africa (SARM-7) and Canada (PTA-1, PTC-1, PTM-1, and SU-1a).
Analytical requirements in international geochemical mapping
Authors: Xie X
Published: November 2013

The history of the development of geochemical exploration has been closely connected with the progress of geoanalysis techniques and instrumentation. The application of spectrographic methods and the development of sensitive colorimetric methods in analyzing
geological materials provided the necessary background for the birth of this new exploration method. The use of atomic absorption spectometry highlighted local and semi-regional scale geochemical exploration in the whole world. Regional and national geochemical mapping became established only when
automatic instruments with multielement analysis capability became available (e.g., the XRF spectrometer, the ICP emission spectrometer, and the neutron activation facility). International geochemical mapping is the inevitable outcome in the trend of development of geochemical exploration. But its
analytical requirements possess some marked differences with its earlier stages due to its international or global nature. ELEMENTS DETERMINED: Elements determined in existing regional or national geochemical mapping projects have been highly diversified. They should be unified in the International
Mapping Program (IGCP 259), but flexibility must be allowed. To solve this problem, the elements will be grouped into six packages and analysis can be made in sequence in these packages according the facility and capability of different laboratories. DETECTION LIMITS: Detection limits of trace and
ultratrace elements should be lowered below their crustal abundance in order to make the geochemical maps of these elements much more informative than before. A proposed list of detection limits is given. ACCURACY: Accuracy is the long-time neglected item in geochemical exploration analysis, because
the exploration geochemist has been mainly interested in looking for the relative contrast of anomalous values with background values. But in International Geochemical Mapping, the interlaboratory bias must be reduced to a minimum to make the data globally comparable. This could be done by
developing unified procedures for selecting optimum methods, and for routine monitoring of the data quality. Primary and secondary standard samples have to be prepared and used in these procedures.
The Analytical Chemistry Laboratory at the Geophysics Institute, UNAM, Mexico
Authors: Armienta M A , Juárez F , Aguayo A
Published: November 2013

The establishment of a chemical laboratory for the analyses of geological materials (rocks and groundwaters) at the Geophysics Institute (UNAM, Mexico) is described. The objective was to establish a laboratory capable of obtaining good quality analyses with
minimum expense. The results had to be adequate to use in the study of rock geochemistry, hydrogeochemistry, and quality of groundwaters. The project is being developed in two stages. The first is to design methods for the quantification of major element oxides in rocks and physicochemical
parameters in waters. For that purpose, wet methods were developed. The second stage in the development of the laboratory has consisted of the establishment of a technique for the quantification of metallic contaminants in waters and trace elements in rocks. These analyses are in development using
an atomic absorption spectrophotometer and a polarograph recently acquired by the laboratory.
A rapid field method for the determination of gold in rocks and soils
Authors: Lu Y
Published: November 2013

Extraction of Au is performed at room temperature using a mixture of thiourea, sulphuric acid, hydrogen peroxide, and ammonium fluoride. Polyurethane foam loaded with active charcoal is used to separate Au from solution. After ashing and extraction of Au into
buffer solution, 0.05 mL of TMK (Thio Micher's ketone) is added and the Au is extracted into a small organic solvent drop for analysis by colorimetry. The method is rapid, simple, and sensitive. The range of determination of Au is from 1 ppb to 10 ppm. Forty determinations can be made in one working
day.
Rapid separation of the rare-earth elements from some matrix interferences prior to analysis by neutron activation
Authors: Robertson R , Burgess D D
Published: November 2013

A simple procedure for pre-irradiation treatment of samples in the determination of rare-earth elements by neutron activation analysis (NAA) is described. Matrix elements are extracted from samples at room temperature using a mixture of hydrofluoric, nitric, and
hydrochloric acids. The remaining solids are retained for NAA. Manganese, uranium, iron, and tantalum are removed effectively while other elements including sodium are partially removed. Thorium is not extracted. The treatment reduces interferences and improves detection
limits.
The present and future of arc source emission spectrometry (AS-ES) in China
Authors: Shen R
Published: November 2013

Detection limits, analytical precision, and accuracy of "old" arc source emission spectrometry (AS-ES) are reviewed and compared with some modern spectrochemical methods. While emphasizing the strong points of AS-ES and its unique capabilities for some analytical
tasks, the inherent weak points and limitations are also pointed out. Some basic approaches towards further development of AS-ES, outlined in this paper, should result in establishing its continuing role in both routine and research-oriented analysis.
Effective porosity of shale samples from the Beaufort-Mackenzie Basin, northern Canada
Authors: Issler D R , Katsube T J
Published: November 2013

Porosity (þ) was determined for 41 shale core samples from 9 petroleum exploration wells in the Beaufort-Mackenzie Basin of northern Canada using the helium porosimetry technique. The samples span a broad depth range (1-4.9 km) and were obtained from regions
which experienced significantly different sedimentation rates during their burial/compaction history. These porosity (þ) values show good agreement with previous measurements (mercury porosimetry method) on a subset of the same samples, and support the suggestion that both helium and water penetrate
pores smaller than 3 nm in diameter. The observed trend of decreasing þ with depth is drastically reduced or reversed in zones of excess pore pressure at depths greater than 2.4-3.4 km. The laboratory-based þ measurements compare favourably with porosity values predicted from sonic logs and verify
the correlation that exists between undercompaction, excess pore pressure, and high sedimentation rate, as inferred from well log analysis.
The distribution of cadmium in a horizon soils in the prairies of Canada and adjoining United States
Authors: Garrett R G
Published: November 2013

Data for Cd determined in the < 2 mm fraction of 1273 Ap horizon soils collected in 1992 across 850 000 km2 of the Canadian Prairies and immediately adjoining United States are presented. Sampling was undertaken using a 7-level stratified random
sampling design whose largest stratum was 80x80 km and included a level for the estimation of analytical variability. Cadmium was determined by flame AAS after dissolution of a 1 g sample with a HF-HClO4-HNO3 acid mixture, the detection limit was 0.2 ppm. The data range is <0.2-3.8 ppm
Cd, with an arithmetic mean of 0.28 ppm and a median of 0.3 ppm. An Analysis of Variance indicates that > 96% of the variability is at scales < 20x20 km. However, there is a small (4%) but significant component of regional variation between the 80x80 km cell means, the
range of which is < 0.2-0.73 ppm. It is concluded that the soils cannot be treated as a spatially homogeneous unit and that geological factors are influencing their composition.
The effects of prolonged oral administration of the disinfectant calcium hypochlorite in Nigerian commercial cockerels
Authors: Iji Temitayo O. , Oyagbemi Ademola A. , Azeez Odunayo I.
Published: November 2013

This study was designed to investigate the effects of prolonged oral administration of calcium hypochlorite in the drinking water of commercial cockerels. It was carried out in order to ascertain probable toxicity associated with prolonged exposure to calcium hypochlorite. Thirty-two healthy birds were used; they were grouped into four groups of eight. Group 1, which served as the control, received 10 mL/kg body weight of physiological saline. Groups 2, 3 and 4 received 0.0375 g, 0.375 g and 0.75 g of calcium hypochlorite per 10 litres of drinking water for six weeks respectively. Six weeks after the administration of calcium hypochlorite, blood was collected from the jugular vein to assess liver function, lipid profiles and for markers of oxidative stress. The results revealed a significant (p 0.05) increase in alanine aminotransferase activity in a dose-dependent manner when compared with the control. Also, there was a significant (p 0.05) increase in aspartate aminotransferase and alkaline phosphatase activity. Similarly, there was a significant (p 0.05) increase in total cholesterol, triglycerides, high-density lipoprotein and low-density lipoprotein levels compared with the control. There was a significant increase in malondialdehyde and hydrogen peroxide generation with a concomitant significant (p 0.05) decrease in serum glutathione level in a dose-dependent manner when compared with the control. In this study, calcium hypochloriteinduced hepatic damage via oxidative stress and decrease in antioxidant defense system was found. Therefore, prolonged exposure of chickens to calcium hypochlorite is potentially harmful.
Chemo-enzymatic Synthesis of Propionyl-ester-linked Taxol-monosaccharide Conjugate and its Drug Delivery System Using Hybrid-Bio-nanocapsules Targeting Brain Glioma Cells
Authors: Hamada Hiroki , Shimoda Kei , Seno Masaharu
Published: November 2013

Taxol is recognized as one of the most potent anticancer agents used in the treatment of breast and ovarian cancers, which are common cancers in women. To overcome its shortcomings, that is, its low water-solubility that reduces drug loading capacity of DDS carriers when incorporating taxol, chemo-enzymatic synthesis of ester-linked taxol-glucose conjugate, i.e., 7-propionyltaxol 2′- O-α-D-glucoside, as a water soluble taxol prodrug was achieved by using a-glucosidase as a glucosylation catalyst. The water-solubility of 7-propionyltaxol 2′- O-α-D-glucoside (25 mM) was 63 fold higher than that of taxol (0.4 mM). The pre-S1 peptide which displays on the surface of bio-nanocapsules, which are nanoparticles composed of the hepatitis B virus surface antigen, was replaced with the antibody affinity motif of protein A. Conjugation of such bio-nanocapsules with anti-human epidermal growth factor receptor antibody gave hybrid bio-nanocapsules. The hybrid bio-nanocapsules were effective for delivering 7-propionyltaxol 2′- O-α-D-glucoside to human brain glioma cells. 7-Propionyltaxol 2′- O-α-D-glucoside was effectively hydrolyzed to give taxol in 95% by human glioma cells. The drug loading capacity of hybrid bio-nanocapsules incorporating 7-propionyltaxol 2′- O-α-D-glucoside was 120 times higher than that incorporating taxol itself.
Values of Twisted Tensor L-functions of Automorphic Forms Over Imaginary Quadratic Fields
Authors: Lanphier Dominic , Skogman Howard , Ochiai Hiroyuki
Published: November 2013

Let K be a complex quadratic extension of and let denote the adeles of K. We find special values at all of the critical points of twisted tensor L-functions attached to cohomological cuspforms on GL2() and establish Galois equivariance of the values. To investigate the values, we determine the archimedean factors of a class of integral representations of these L–functions, thus proving a conjecture due to Ghate. We also investigate analytic properties of these L–functions, such as their functional equations.
The Sandwich Denture—A Novel Way to reduce Ridge Resorption
Authors: Bansal Siddharth , Aras Meena
Published: November 2013

Many edentulous patients with severely resorbed ridge complain of loss of retention and discomfort with the use of conventional complete dentures. Basic principles of retention, stability and support are lost in these patients as overlying mucosa is thin and nonresilient. This article describes a case report of a 52-year-old completely edentulous female patient with severely resorbed mandibular ridge where a novel technique was used by sandwiching a layer of permanent soft resilient liner (Molloplast-B) between the denture teeth and denture base to reduce traumatic impact of masticatory forces on residual ridges and thereby reducing the residual ridge resorption. The resilient layer acts as a ‘shock absorber’ or ‘stress distributor’.

How to cite this article

Bansal S, Aras M, Chitre V. The Sandwich Denture—A Novel Way to reduce Ridge Resorption. Int J Prosthodont Restor Dent 2013;3(2):68-71.
Unemployment Benefits and Financial Leverage in an Agent Based Macroeconomic Model
Authors: Riccetti Luca , Russo Alberto , Gallegati Mauro
Published: November 2013

This paper is aimed at investigating the effects of government intervention through unemployment benefits on macroeconomic dynamics in an agent based decentralized matching framework. The major result is that the presence of such a public intervention in the economy stabilizes the aggregate demand and the financial conditions of the system at the cost of a modest increase of both the inflation rate and the ratio between public deficit and nominal GDP. The successful action of the public sector is sustained by the central bank which is committed to buy outstanding government securities.
The evolution of shipping emissions and the costs of regulation changes in the northern EU area
Authors: Johansson L. , Jalkanen J.-P. , Kalli J. , Kukkonen J.
Published: November 2013

Abstract. An extensive inventory of marine exhaust emissions is presented in the northern European emission control area (ECA) in 2009 and 2011. The emissions of SOx, NOx, CO2, CO and PM2.5 were evaluated using the Ship Traffic Emission Assessment Model (STEAM). We have combined the information on individual vessel characteristics and position reports generated by the automatic identification system (AIS). The emission limitations from 2009 to 2011 have had a significant impact on reducing the emissions of both SOx and PM2.5. The predicted emissions of SOx originated from IMO (International Maritime Organization)-registered marine traffic have been reduced by 29%, from 320 kt to 231 kt, in the ECA from 2009 to 2011. The corresponding predicted reduction of PM2.5 emissions was 17%, from 72 kt to 61 kt. The highest CO2 and PM2.5 emissions in 2011 were located in the vicinity of the coast of the Netherlands, in the English Channel, near the south-eastern UK and along the busiest shipping lines in the Danish Straits and the Baltic Sea. The changes of emissions and the financial costs caused by various regulative actions since 2005 were also evaluated, based on the increased direct fuel costs. We also simulated the effects and direct costs associated with the forthcoming switch to low-sulfur distillate fuels in 2015. According to the projections for the future, there will be a reduction of 87% in SOx emissions and a reduction of 48% in PM2.5 emissions in 2015, compared with the corresponding shipping emissions in 2011 in the ECA. The corresponding relative increase in fuel costs for all IMO-registered shipping varied between 13% and 69%, depending on the development of the prices of fuels and the use of the sulfur scrubber equipment.
Quantifying aerosol mixing state with entropy and diversity measures
Authors: Riemer N. , West M.
Published: November 2013

Abstract. This paper presents the first quantitative metric for aerosol population mixing state, defined as the distribution of per-particle chemical species composition. This new metric, the mixing state index χ, is an affine ratio of the average per-particle species diversity Dα and the bulk population species diversity Dγ, both of which are based on information-theoretic entropy measures. The mixing state index χ enables the first rigorous definition of the spectrum of mixing states from so-called external mixture to internal mixture, which is significant for aerosol climate impacts, including aerosol optical properties and cloud condensation nuclei activity. We illustrate the usefulness of this new mixing state framework with model results from the stochastic particle-resolved model PartMC-MOSAIC. These results demonstrate how the mixing state metrics evolve with time for several archetypal cases, each of which isolates a specific process such as coagulation, emission, or condensation. Further, we present an analysis of the mixing state evolution for a complex urban plume case, for which these processes occur simultaneously. We additionally derive theoretical properties of the mixing state index and present a family of generalized mixing state indexes that vary in the importance assigned to low-mass-fraction species.
Comparison of inorganic nitrogen uptake dynamics following snowmelt and at peak biomass in subalpine grasslands
Authors: Legay N. , Grassein F. , Robson T. M. , Personeni E. , Bataillé M.-P. , Lavorel S. , Clément J.-C.
Published: November 2013

Abstract. Subalpine grasslands are highly seasonal environments and likely subject to strong variability in nitrogen (N) dynamics. Plants and microbes typically compete for N acquisition during the growing season and particularly at plant peak biomass. During snowmelt, plants could potentially benefit from a decrease in competition by microbes, leading to greater plant N uptake associated with active growth and freeze-thaw cycles restricting microbial growth. In managed subalpine grasslands, we expect these interactions to be influenced by recent changes in agricultural land use, and associated modifications in plant and microbial communities. At several subalpine grasslands in the French Alps, we added pulses of 15N to the soil at the end of snowmelt, allowing us to compare the dynamics of inorganic N uptake in plants and microbes during this period with that previously reported at the peak biomass in July. In all grasslands, while specific shoot N translocation (per g of biomass) of dissolved inorganic nitrogen (DIN) was two to five times greater at snowmelt than at peak biomass, specific microbial DIN uptakes were similar between the two sampling dates. On an area basis, plant communities took more DIN than microbial communities at the end of snowmelt when aboveground plant biomasses were at least two times lower than at peak biomass. Consequently, inorganic N partitioning after snowmelt switches in favor of plant communities, allowing them to support their growing capacities at this period of the year. Seasonal differences in microbial and plant inorganic N-related dynamics were also affected by past (terraced vs. unterraced) rather than current (mown vs. unmown) land use. In terraced grasslands, microbial biomass N remained similar across seasons, whereas in unterraced grasslands, microbial biomass N was higher and microbial C : N lower at the end of snowmelt as compared to peak biomass. Further investigations on microbial community composition and their organic N uptake dynamics are required to better understand the decrease in microbial DIN uptake.
Methane production correlates positively with methanogens, sulfate-reducing bacteria and pore water acetate at an estuarine brackish-marsh landscape scale
Authors: Tong C. , She C. X. , Jin Y. F. , Yang P. , Huang J. F.
Published: November 2013

Abstract. Methane production is influenced by the abundance of methanogens and the availability of terminal substrates. Sulfate-reducing bacteria (SRB) also play an important role in the anaerobic decomposition of organic matter. However, the relationships between methane production and methanogen populations, pore water terminal substrates in estuarine brackish marshes are poorly characterized, and even to our knowledge, no published research has explored the relationship between methane production rate and abundance of SRB and pore water dimethyl sulfide (DMS) concentration. We investigated methane production rate, abundances of methanogens and SRB, concentrations of pore water terminal substrates and electron acceptors at a brackish marsh landscape dominated by Phragmites australis, Cyperus malaccensis and Spatina alterniflora marshes zones in the Min River estuary. The average rates of methane production at a soil depth of 30 cm in the three marsh zones were 0.142, 0.058 and 0.067 μg g−1 d−1, respectively. The abundance of both methanogens and SRB in the soil of the P. australis marsh with highest soil organic carbon content was higher than in the C. malaccensis and S. alterniflora marshes. The abundance of methanogens and SRB in the three soil layers was statistically indistinguishable. Mean pore water DMS concentrations at a soil depth of 30 cm under the S. alterniflora marsh were higher than those in the C. malaccensis and P. australis marshes. Methane production rate increased with the abundance of both methanogens and SRB across three marsh zones together at the landscape scale, and also increased with the concentration of pore water acetate, but did not correlate with concentrations of pore water DMS and dissolved CO2. Our results suggest that, provided that substrates are available in ample supply, methanogens can continue to produce methane regardless of whether SRB are prevalent in estuarine brackish marshes.
Paleo Agulhas rings enter the subtropical gyre during the penultimate deglaciation
Authors: Scussolini P. , van Sebille E. , Durgadoo J. V.
Published: November 2013

Abstract. A maximum in the strength of Agulhas leakage has been registered at the interface between the Indian and South Atlantic oceans during glacial Termination II (T-II). This presumably transported the salt and heat necessary for maintaining the Atlantic circulation at rates similar to the present day. However, it was never shown whether these waters were effectively incorporated into the South Atlantic gyre, or whether they retroflected into the Indian and/or Southern oceans. To resolve this question, we investigate the presence of paleo Agulhas rings from a sediment core on the central Walvis Ridge, almost 1800 km farther into the Atlantic Basin than previously studied. Analysis of a 60 yr data set from the global-nested INALT01 model allows us to relate density perturbations at the depth of the thermocline to the passage of individual rings over the core site. Using this relation from the numerical model as the basis for a proxy, we generate a time series of variability of individual Globorotalia truncatulinoides δ18O. We reveal high levels of pycnocline depth variability at the site, suggesting enhanced numbers of Agulhas rings moving into the South Atlantic Gyre around T-II. Our record closely follows the published quantifications of Agulhas leakage from the east of the Cape Basin, and thus shows that Indian Ocean waters entered the South Atlantic circulation. This provides crucial support for the view of a prominent role of the Agulhas leakage in the shift from a glacial to an interglacial mode of the Atlantic circulation.
The IRHUM (Isotopic Reconstruction of Human Migration) database – bioavailable strontium isotope ratios for geochemical fingerprinting in France
Authors: Willmes M. , McMorrow L. , Kinsley L. , Armstrong R. , Aubert M. , Eggins S. , Falguères C. , Maureille B. , Moffat I. , Grün R.
Published: November 2013

Abstract. Strontium isotope ratios (87Sr/86Sr) are a key geochemical tracer used in a wide range of fields including archaeology, ecology, food and forensic sciences. These applications are based on the principle that the Sr isotopic ratios of natural materials reflect the sources of strontium available during their formation. A major constraint for current studies is the lack of robust reference maps to evaluate the source of strontium isotope ratios measured in the samples. Here we provide a new dataset of bioavailable Sr isotope ratios for the major geologic units of France, based on plant and soil samples (Pangaea data repository doi:10.1594/PANGAEA.819142). The IRHUM (Isotopic Reconstruction of Human Migration) database is a web platform to access, explore and map our dataset. The database provides the spatial context and metadata for each sample, allowing the user to evaluate the suitability of the sample for their specific study. In addition, it allows users to upload and share their own datasets and data products, which will enhance collaboration across the different research fields. This article describes the sampling and analytical methods used to generate the dataset and how to use and access of the dataset through the IRHUM database. Any interpretation of the isotope dataset is outside the scope of this publication.
An assessment of landslide distribution in the Faifa area, Saudi Arabia, using remote sensing and GIS techniques
Authors: Alharbi T. , Sultan M. , Sefry S. , El Kadiri R. , Ahmed M. , Chase R. , Milewski A. , Abdullah M. A. , Emil M. , Chounaird K.
Published: November 2013

Abstract. An integrated approach was adopted over Faifa Mountain and its surroundings, Saudi Arabia, to identify landslide types, distribution, and controlling factors, and to generate landslide hazard maps (HMs). Given the inaccessibility of the area, we relied on remote sensing observations and GIS-based applications to enable spatial analysis of data and extrapolation of limited field observations. HMs were generated depicting debris flows within ephemeral valleys and on sparsely vegetated slopes (Type I), and landslides caused by failure along fracture planes (Type II). Type I HMs were generated applying linear relationships between Normalized Difference Vegetation Index (NDVI) and slope values and threshold slope values (ephemeral valleys: 30°; overland flows: 40.9°) that were both extracted over known debris flow locations. For Type II HMs, landslides were predicted if fracture planes had strike values similar (within 20°) to those of the slope face strike and dip angles exceeding the friction, but not slope angles. Comparisons between predicted and observed debris flows yielded success rates of 82% (ephemeral valleys) and 75% (overland flows); unverified predictions are interpreted as future locations of debris flows. Our approach could serve as a replicable model for many areas worldwide, where field measurements are difficult to obtain and/or are cost prohibitive.
Use of phytoremediation and biochar to remediate heavy metal polluted soils: a review
Authors: Paz-Ferreiro J. , Lu H. , Fu S. , Méndez A. , Gascó G.
Published: November 2013

Abstract. Anthropogenic activities are resulting in an increase on the use and extraction of heavy metals. Heavy metals cannot be degraded and hence accumulate in the environment having the potential to contaminate the food chain. This pollution threatens soil quality, plant survival and human health. The remediation of heavy metals deserves attention, but it is impaired by the cost of these processes. Phytoremediation and biochar are two sound environmental technologies which could be at the forefront to mitigate soil pollution. This review provides an overview of the current state of knowledge phytoremediation and biochar application to remediate heavy metal contaminated soils, discussing the advantages and disadvantages of both individual approaches. Research to date has attempted only in a limited number of occasions to combine both techniques, however we discuss the potential advantages of combining both remediation techniques and the potential mechanisms involved in the interaction between phytoremediators and biochar. We identified specific research needs to ensure a sustainable use of phytoremediation and biochar as remediation tools.
General Inquisitors and the Portuguese Crown in the Seventeenth Century: Between Political Service and the Defense of the Faith (1578–1705)
Authors: López-Salazar Ana Isabel
Published: November 2013

The Inquisition was established in Portugal in 1536. From the beginning, the pope authorized the Portuguese king to choose the General Inquisitor, who was granted authority by the pope to pursue and punish crimes of heresy. This article investigates the Portuguese General Inquisitors during the seventeenth century in order to establish their social background, politics, ecclesiastical careers, and links with the Crown. The aim is to discover the relationships they had with the Crown and to understand how far they managed to preserve the autonomy of the Inquisition in relation to the Crown and the Holy See.
Impact of Surf Breaks on Home Prices in Santa Cruz, CA
Authors: Scorse Jason , Reynolds Frank , Sackett Amanda
Published: November 2013

The growing field of ‘surfonomics' attempts to document surfing's economic contribution to local and regional communities, as well as the consumer surplus that surf breaks provide to millions of surfers. To date, no research has examined the extent to which the value of surf breaks is capitalized into home prices. This study uses the hedonic price method with data from three distinct beach-adjacent neighbourhoods in Santa Cruz, CA, USA, to estimate whether proximity to surf breaks leads to higher home values. The authors find that, after controlling for proximity to the beach, ocean views, the specific characteristics of the homes and neighbourhood effects, proximity to surf breaks is a statistically significant contributor to overall home value. A home that is right next to a surf break is valued on average at approximately US$106,000 more than an equivalent home a mile away.
Chemical Compositions and Nutritional Properties of Popcorn-Based Complementary Foods Supplemented With Moringa oleifera Leaves Flour
Authors: Steve Ijarotimi Oluwole , Babatunde Oluwalana Isaac
Published: November 2013

Cereal gruel is the common complementary foods in developing countries, and it is usually low in energy and protein; hence, responsible for increase in protein-energy malnutrition among underprivileged weaning aged children. Several locally available food materials have been tested in combination for infant food formulations however; popcorn and Moringa oleifera leaves combination have not been used. After blanching and fermentation processing, popcorn and moringa leaves were milled into flour and blended to obtain, blanched popcorn-moringa leaves (BPM) (65% popcorn and 35% moringa leaves flour) and fermented popcorn-moringa leaves (FPM) (65% popcorn and 35% moringa leaves flour). Products were analyzed for chemical composition, functional properties and bioassay using standard methods. Protein content of FPM (21.27 ± 0.20 g/100 g) and BPM (15.99 ± 0.14 g/100 g) were higher than Cerelac (15.75 ± 0.01 g/100 g) and ‘Ogi’ (6.52 ± 0.31 g/100 g); while energy values of FPM (393.94 ± 0.39 kcal) and BPM (389.69 ± 1.40 Kcal) were lower than ‘Ogi’ (418.08 ± 0.47 kcal) and Cerelac (431.58 ± 0.01 kcal). Mineral contents of BPM were higher in zinc, iron, potassium, sodium and phosphorous, while FPM sample was higher in copper, calcium and magnesium, and were lower than Cerelac. Oxalate, phytate and trypsin inhibitor in FPM were lower than BPM. Biological value and protein efficiency ratio of FPM were higher than BPM and ‘Ogi’, but lower than Cerelac. The albino rats fed with the FPM had higher growth rate when compared with those rats fed with BPM sample and ‘Ogi’, but lower than those fed with Cerelac. Nutrient composition and nutritional profile of popcorn-moringa leaves based complementary foods could be used as substitutes for local complementary foods, which are low in protein and energy.
Preparation of 1,2,5,6,9,10-Hexaalkoxyhexahelicenes
Authors: Schwertel Manfred , Hillmann Sabine , Meier Herbert
Published: November 2013

1,2,5,6,9,10-Hexaalkoxyhexahelicenes 3 represent [3]star compounds with a helical core. A multistep synthetic concept for 3 is discussed, in which the final step 16→3 is a twofold oxidative photocyclization. The linearly conjugated compounds 16 contain stilbene and vinylnaphthalene units