bluuebunny/crossref_metadata_2025_split huggingface dataset:
Design of Simultaneous Enhanced Oil Recovery and Carbon Dioxide Storage With Potential Application to Offshore Trinidad
Authors: Sobers Lorraine E. , Blunt Martin J. , LaForce Tara C. 
Published: February 2013

Summary
We developed an injection strategy to recover moderately heavy oil and store carbon dioxide (CO2) simultaneously. Our compositional simulations are founded on pressure/volume/temperature- (PVT-) matched properties of oil found in an unconsolidated deltaic sandstone deposit in the Gulf of Paria, offshore Trinidad. In this region, oil density ranges between 940 and 1010 kg/m3 (9 to 18°API). We use countercurrent injection of gas and water to improve reservoir sweep and trap CO2 simultaneously; water is injected in the upper portion of the reservoir, and gas is injected in the lower portion. The two water-injection rates investigated, 100 and 200 m3/d, correspond to the water-gravity numbers 6.3 to 3.1 for our reservoir properties. We applied this injection strategy using vertical producers with two injection configurations: single vertical injector and a pair of horizontal parallel laterals in a simplified representation of the unconsolidated Forest sand found offshore Trinidad. Twelve simulation runs were conducted, varying injection-gas composition for miscible- and immiscible-gas drives, water-injection rate, and injection-well orientation. Our results show that water-over-gas injection can realize oil recoveries ranging from 17 to 30%. In each instance, more than 50% of injected CO2 remained in the reservoir, with less than 15% of the retained CO2 in the mobile phase.
Electrical transport properties of poly(aniline-co-p-phenylenediamine) and its composites with incorporated silver particles
Authors: Moucka Robert , Mrlik Miroslav , Ilcikova Marketa , Spitalsky Zdenko , Kazantseva Natalia , Bober Patrycja , Stejskal Jaroslav 
Published: February 2013

AbstractStatistical copolymers of aniline and p-phenylenediamine, poly(aniline-co-p-phenylenediamine)s, were synthesised by oxidative polymerisation using various oxidants, ammonium peroxydisulphate or silver nitrate. Depending on the choice of oxidant, copolymers or composites with silver particles were obtained. Different molar concentrations of p-phenylenediamine in the reaction mixture provided materials of different conductivities. The influence of both the copolymer composition and the presence of discrete silver particles on the electric and dielectric properties of the system was studied. The results showed a decrease in the conductivity of copolymers and their composites with the silver content compared with the content of standard polyaniline salt. The reduction in conductivity was described in terms of the decreased density of hopping centres due to defects in the copolymer structure. The dielectric relaxations observed were described in terms of their activation energies and were linked to the corresponding conduction mechanism.
Anti-oxidative properties of bi-1,2,4-triazine bisulphides
Authors: Piszcz Paweł , Głód Bronisław 
Published: February 2013

AbstractThe anti-oxidative properties of bitriazines (BTs) were evaluated using HPLC and cyclic voltammetry. In the first case, a RP-HPLC assay was made, using a fluorescence detector, hydroxyl radicals generated in Fenton reaction, and terephthalic acid as a spin trap. The measurements were performed using aqueous or methanolic solutions. It was found that when the BTs were dissolved in water they were antioxidants, while dissolved in methanol they were pro-oxidants. Their different physicochemical properties in both solvents were confirmed by voltammetric, chromatographic as well as spectrophotometric measurements.
A New HPLC Method with Fluorescence Detection for the Determination of Memantine in Human Plasma
Authors: Tekkeli Serife Evrim Kepekci , Toker Sidika Erturk 
Published: February 2013

Abstract
A sensitive and selective HPLC method with fluorometric detection was developed for the determination of memantine in human plasma and applied to a pharmacokinetic study. Memantine was precolumn derivatized with 9-fluorenylmethyl chloroformate, and the fluorescent derivative was separated on an RP C18 column using a mobile phase composed of acetonitrile–10 mM orthophosphoric acid containing 1 mL/L triethylamine with gradient elution. The method was based on the measurement of the derivative using fluorescence detection at 310 nm with excitation at 260 nm. The calibration curve was linear over the range 1.0–50.0 ng/mL. LOD and LOQ were found to be 0.3 and 1.0 ng/mL, respectively. Intraday and interday RSD values were less than 3.39%.
Determination of Volatile Organic Compounds in Air by GC/MS: Italian Proficiency Tests
Authors: Formenton Gianni , Bassetto Anna , De Lorenzo Roberta 
Published: February 2013

Abstract
Three national proficiency scheme rounds on the analysis of volatile organic compounds (VOCs) in air have been organized; the first between April and June 2007, the second between May and July 2008, and the third between April and June 2010. A group of about 10 Italian laboratories used the U.S. Environmental Protection Agency Method TO-15 for the determination of VOCs in air collected in canisters. A canister containing a VOC mixture, prepared by dynamic dilution from certified reference materials, was shipped to each participating laboratory; VOC concentrations were between 2 and 50 parts per billion by volume. Homogeneity of the samples prepared was tested and considered adequate according to ISO 13528:2005(E); stability was also checked. The canisters were analyzed by the laboratories within 30 days by GC/MS. The data were analyzed by robust statistics. Good accordance among laboratory results was obtained.
Determination of pKa Values of Some Antipsychotic Drugs by HPLC—Correlations with the Kamlet and Taft Solvatochromic Parameters and HPLC Analysis in Dosage Forms
Authors: Sanli Senem , Kmese Ediha , Altun Yuksel 
Published: February 2013

Abstract
In this study, ionization constant (pKa) values were determined by using the dependence of the retention factor on the pH of the mobile phase for four ionizable drugs, namely, risperidone (RI), clozapine (CL), olanzapine (OL), and sertindole (SE). The effect of the mobile phase composition on the pKa was studied by measuring the pKa at different acetonitrile–water mixtures in an HPLC-UV method. To explain the variation of the pKa values obtained over the whole composition range studied, the quasi-lattice quasi-chemical theory of preferential solvation was applied. The pKa values of drugs were correlated with the Kamlet and Taft solvatochromic parameters. Kamlet and Taft's general equation was reduced to two terms by using combined factor analysis and target factor analysis in these mixtures: the independent term and the hydrogen-bond donating ability α. The HPLC-UV method was successfully applied for the determination of RI, OL, and SE in pharmaceutical dosage forms. CL was chosen as an internal standard. Additionally, the repeatability, reproducibility, selectivity, precision, and accuracy of the method in all media were investigated and calculated.
Establishment and Validation of an HPLC Quantification Method for Quality Control of Semen Oroxyli
Authors: Yang Xiaorong , Miao Jianhua , Ma Xiaojun , Xiao Peigen 
Published: February 2013

Abstract
Semen Oroxyli is a medicinal plant widely used in traditional Chinese medicine. In this study, an improved and comprehensive analytical method suitable for QC of Semen Oroxyli was optimized and fully validated according to International Conference on Harmonization guidelines in terms of linearity, precision, and accuracy. With this method, four flavonoids in Semen Oroxyli plant material were simultaneously quantitatively analyzed for the first time. The sample treatment procedure and HPLC conditions were investigated and optimized. HPLC separation was carried out on a C18 column; the detection wavelength was set at 280 nm. The mobile phase was a two-phase system consisting of water, acetic acid, and acetonitrile using a linear gradient. The RSDs within levels and between levels, as well as within and between days, were less than the acceptance limit of 5% for the tested analytes. The mean recoveries of the four marker constituents were, respectively, 99.60, 101.8, 98.84, and 102.9%, with no significant difference from 100%. The validation data showed the developed method was suitable for the QC of the Semen Oroxyli plant material and products thereof.
Determination of Ginsenoside Content in Panax ginseng C.A. Meyer and Panax quinquefolius L. Root Materials and Finished Products by High-Performance Liquid Chromatography with Ultraviolet Absorbance Detection: Interlaboratory Study
Authors: Brown Paula N , Yu Ronan ,   Collaborators:, Cain T , Huie G , Jin C D , Kababick J N , Leong G , LeVanseler K , Lunetta S , Ma Y C , Reif K , Schaneberg B , Shevchuk C , Smith R , Sullivan D , Wijewickreme N , Windust A 
Published: February 2013

Abstract
An interlaboratory study was conducted on an HPLC method with UV absorbance detection, previously validated using AOAC single-laboratory validation guidelines, for the determination of the six major ginsenosides (Rg1, Re, Rb1, Rc, Rb2, and Rd) in Panax ginseng C. A. Meyer and Panax quinquefolius L. root materials, extracts, and finished products. Fourteen participating laboratories analyzed five test materials (P. ginseng whole root, P. ginseng powdered extract, P. quinquefolius whole root, P. quinquefolius powdered extract, and P. ginseng powdered extract spiked in a matrix blank) as blind duplicates, and two test materials (P. ginseng powdered whole root tablet and P. quinquefolius powdered extract hard-filled capsule) as single samples. Due to the variability of the ginsenosides (low level concentration of Rb2 in P. quinquefolius raw materials and in P. ginseng spiked matrix blanks, and the possibility of incomplete hydrolysis of the finished products during processing), it was deemed more applicable to analyze total ginsenosides rather than individual ones. Outliers were evaluated and omitted using the Cochran's test and single and double Grubbs' tests. The reproducibility RSD (RSDR) for the blind duplicate samples ranged from 4.38 to 5.39%, with reproducibility Horwitz Ratio (HorRatR) values ranging from 1.5 to 1.9. For the single replicate samples, the data sets were evaluated solely by their repeatability HorRat (HorRatr), which were 2.9 and 3.5 for the capsule and tablet samples, respectively. Based on these results, the method is recommended for AOAC Official First Action for the determination of total ginsenosides in P. ginseng and P. quinquefolius root materials and powdered extracts.
Synthesis of Chiral Amino Acid Anilides by Ligand‐Free Copper‐Catalyzed Selective N‐Arylation of Amino Acid Amides
Authors: Dong Junyu , Wang Yan , Xiang Qinjie , Lv Xirui , Weng Wen , Zeng Qingle 
Published: February 2013

AbstractAn atom‐economic, practical and cost‐effective protocol for synthesis of chiral amino acid anilides via ligand‐free copper‐catalyzed selective CN cross coupling of chiral amino acid amides and aryl halides, hetereoaryl halides and a vinyl bromide has been developed. No racemization occurred during the CN coupling. A plausible mechanism is proposed.
Recent Advances in Asymmetric Organocatalytic Construction of 3,3′‐Spirocyclic Oxindoles
Authors: Hong Liang , Wang Rui 
Published: February 2013

AbstractThe asymmetric organocatalysis is definitely one of the most powerful and versatile tools for the rapid construction of various spirocyclic oxindoles. In the past few years, a number of successful strategies based on organocatalysis have been developed for the construction of 3,3′‐spirocyclic oxindoles in high yields and excellent enantioselectivities under mild conditions. In this review, recent advances in this area are summarized and classified according to the spiro ring fused at the 3‐position of the oxindole core.
High‐Selective Tramadol Sensor Based on Modified Molecularly Imprinted PolymerCarbon Paste Electrode with Multiwalled Carbon Nanotubes
Authors: Soleimani Majid , Afshar Majid Ghahraman , Shafaat Atefeh , Crespo Gastón A. 
Published: February 2013

AbstractWe report here a novel carbon paste electrode (CPE) which is able to quantitatively sense tramadol under physiological conditions without sample preparation step. The selectivity of CPE is modified by applying molecularly imprinted polymer (MIP) technology. Multiwalled carbon nanotubes (MWCNTs) are incorporated in the structure of CPE to improve the conductivity and the ion‐to‐electron transduction. The electrode shows a wide dynamic linear range for tramadol from 10−7 to 10−3 M. The observed limit of detection and % RSD are 5×10−7 M and 1.8 %, respectively. Finally, the proposed method is applied to determine tramadol in urine and medicinal tablets.
Dissolution in a variably confined carbonate platform: effects of allogenic runoff, hydraulic damming of groundwater inputs, and surface–groundwater exchange at the basin scale
Authors: Gulley J. , Martin J. , Spellman P. , Moore P. , Screaton E. 
Published: February 2013

ABSTRACTIn variably confined carbonate platforms, impermeable confining units collect rainfall over large areas and deliver runoff to rivers or conduits in unconfined portions of platforms. Runoff can increase river stage or conduit heads in unconfined portions of platforms faster than local infiltration of rainfall can increase groundwater heads, causing hydraulic gradients between rivers, conduits and the aquifer to reverse. Gradient reversals cause flood waters to flow from rivers and conduits into the aquifer where they can dissolve limestone. Previous work on impacts of gradient reversals on dissolution has primarily emphasized individual caves and little research has been conducted at basin scales. To address this gap in knowledge, we used legacy data to assess how a gradient of aquifer confinement across the Suwannee River Basin, north‐central Florida affected locations, magnitudes and processes of dissolution during 2005–2007, a period with extreme ranges of discharge. During intense rain events, runoff from the confining unit increased river stage above groundwater heads in unconfined portions of the platform, hydraulically damming inputs of groundwater along a 200 km reach of river. Hydraulic damming allowed allogenic runoff with SICAL < −4 to fill the entire river channel and flow into the aquifer via reversing springs. Storage of runoff in the aquifer decreased peak river discharges downstream and contributed to dissolution within the aquifer. Temporary storage of allogenic runoff in karst aquifers represents hyporheic exchange at a scale that is larger than found in streams flowing over non‐karst aquifers because conduits in karst aquifers extend the area available for exchange beyond river beds deep into aquifers. Post‐depositional porosity in variably confined carbonate platforms should thus be enhanced along rivers that originate on confining units. This distribution should be considered in models of porosity distribution used to manage water and hydrocarbon resources in carbonate rocks. Copyright © 2013 John Wiley & Sons, Ltd.
Seismic stratigraphic evidence for glacial expanse during glacial maxima in the Yakutat Bay Region, Gulf of Alaska
Authors: Elmore Christopher R. , Gulick Sean P. S. , Willems Bryce , Powell Ross 
Published: February 2013

AbstractModern shelf bathymetry bordering the Gulf of Alaska exhibits shelf‐crossing sea valleys that suggest focused pathways for ice flow during glacial conditions. Using an integrated seismic data set between the present Yakutat and Alsek Sea Valleys, we investigate the glacial stratigraphic record in order to improve our understanding of the regional glacial system during maximum glacial conditions. Our investigations reveal four glacial unconformities, of which, the latter two are overlain by sediment packages hundreds of meters thick. We suggest that these unconformities are indicative of ice advance phases during the Little Ice Age (LIA), the Last Glacial Maxima (LGM), and two pre‐LGM advances with glacial retreat sequences preserved from the youngest two. The advances were dominated by ice expanse from the Malaspina Glacial system and Alsek River districts rather than the Hubbard Glacial system and only show distinctive morainal bank development near the shelf edge and near the mouth of, or within, modern bays, fjords, or river valleys. This observation strongly supports rapid and continuous retreat from glacial maxima conditions during climatic warming. All, except the inferred LIA sequence, transgress the shelf and exhibit concentrated erosion in overdeepened troughs, analogous to cross‐shelf troughs similar to those observed on other high‐latitude glaciated shelves. The two Alaskan troughs discussed here may be end‐member examples of high‐sediment flux systems due to the temperate glacial setting combined with an actively exhuming orogen.
Remotely triggered micro‐earthquakes in the Larderello‐Travale Geothermal Field (Italy) following the 2012 May 20, Mw 5.9 Po‐plain earthquake
Authors: Saccorotti G. , Piccinini D. , Mazzarini F. , Zupo M. 
Published: February 2013

AbstractWe report observations of remotely triggered earthquakes at the Larderello‐Travale Geothermal Field (Italy), following the Mw = 5.9 Po‐Plain earthquake on 20 May 2012. Four distinct triggered events are recognized within a short (~25 s) time interval accompanying the sweeping of ~10s Rayleigh waves. Triggered sources are clustered at depths in between 4 km and 6 km. The magnitude and distance of the mainshock agree well with the triggering threshold previously proposed for The Geysers, California. For three out of four earthquakes, the Rayleigh wave dynamic stresses are mostly associated with extensional vertical (szz) and shear (sxz) components, which range up to 5 KPa. Once considering the structural setting of the area, the most likely triggering mechanism involves the rupture of normal faults which are kept close to failure by high‐pressure crustal fluids.
Production, Purification and Partial Characterization of Four Lipases from a Thermophile Isolated from Deception Island
Authors: Muñoz Patricio A. , Correa‐Llantén Daniela N. , Blamey Jenny M. 
Published: February 2013

AbstractFour lipases were purified from ID17, a thermophilic bacterium belonging to Geobacillus genus isolated from Deception Island, Antarctica. Lipase activity was detected by opacity test and p‐nitrophenyl laurate methods. Lipase production was better in a medium containing tryptone as the carbon and nitrogen source, without non‐ionic detergents and pH 7.5. Proteins were ultrafiltered from supernatant and separated using anion exchange and size exclusion chromatography resulting in four distinct fractions with lipase activity (called Lip1–4). Purified lipases showed an optimal pH at 9.0, 9.5, 10.0 and 8.0 and temperature at 65, 70, 75 and 80 °C for Lip1–4, respectively. Lip1 and Lip2 showed higher activity using p‐nitrophenol decanoate as substrate, whereas Lip3 and Lip4 prefer p‐nitrophenol laurate. Based on their molecular weight Lip1 and Lip2 are trimeric and pentameric proteins, respectively, whereas Lip3 and Lip4 are monomeric proteins. Lip1 was exceptionally thermostable maintaining 70 % of its activity after incubating it at 70 °C for 8 h. Based on their characteristics, the four lipases obtained from ID17 are good candidates to understand the mechanisms of lipase stability and to be used in different types of industrial applications.
Auditory habituation in the fetus and neonate: an fMEG study
Authors: Muenssinger Jana , Matuz Tamara , Schleger Franziska , Kiefer‐Schmidt Isabelle , Goelz Rangmar , Wacker‐Gussmann Annette , Birbaumer Niels , Preissl Hubert 
Published: February 2013

AbstractHabituation – the most basic form of learning – is used to evaluate central nervous system (CNS) maturation and to detect abnormalities in fetal brain development. In the current study, habituation, stimulus specificity and dishabituation of auditory evoked responses were measured in fetuses and newborns using fetal magnetoencephalography (fMEG). An auditory habituation paradigm consisting of 100 trains of five 500 Hz tones, one 750 Hz tone (dishabituator) and two more 500 Hz tones, respectively, were presented to 41 fetuses (gestational age 30–39 weeks) and 22 newborns or babies (age 6–89 days). A response decrement between the first and fifth tones (habituation), an increment between the fifth tone and the dishabituator (stimulus specificity) and an increment between the fifth (last tone before the dishabituator) and seventh tones (first tone after the dishabituator) (dishabituation) were expected. Fetuses showed weak responses to the first tone. However, a significant response decrement between the second and fifth tones (habituation) and a significant increment between the fifth tone and the dishabituator (stimulus specificity) were found. No significant difference was found for dishabituation nor was a developmental trend found at the group level. From the neonatal data, significant values for stimulus specificity were found. Sensory fatigue or adaptation was ruled out as a reason for the response decrement due to the strong reactions to the dishabituator. Taken together, the current study used fMEG to directly show fetal habituation and provides evidence of fetal learning in the last trimester of pregnancy.
Target Article with Commentaries: Developmental niche construction
Authors: Flynn Emma G. , Laland Kevin N. , Kendal Rachel L. , Kendal Jeremy R. 
Published: February 2013

AbstractNiche construction is the modification of components of the environment through an organism's activities. Humans modify their environments mainly through ontogenetic and cultural processes, and it is this reliance on learning, plasticity and culture that lends human niche construction a special potency. In this paper we aim to facilitate discussion between researchers interested in niche construction and those interested in human cognitive development by highlighting some of the related processes. We discuss the transmission of culturally relevant information, how the human mind is a symbol‐generating and artefact‐devising system, and how these processes are bi‐directional, with infants and children both being directed, and directing, their own development. We reflect on these in the light of four approaches: natural pedagogy, activity theory, distributed cognition and situated learning. Throughout, we highlight pertinent examples in non‐humans that parallel or further explicate the processes discussed. Finally we offer three future directions; two involving the use of new techniques in the realms of neuroscience and modelling, and the third suggesting exploration of changes in the effects of niche construction across the lifespan.