bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analysis of succinylacetone, as a Girard T derivative, in urine and dried bloodspots by flow injection electrospray ionization tandem mass spectrometry
Authors: Johnson David W. , Gerace Rosemarie , Ranieri Enzo , Trinh Minh‐Uyen , Fingerhut Ralph 
Published: November 2006

AbstractFlow injection electrospray ionization tandem mass spectrometric methods for succinylacetone (SA) in 250 µL urine, using d5‐SA as internal standard, and in 3 mm dried bloodspots, using 13C4‐SA as internal standard, are described. Selectivity and sensitivity of analysis is achieved by the use of a mono‐Girard T derivative. Measured SA infant urine normal range (n = 20) is 0.013–0.27 µmol/mmol creatinine. Measured SA newborn bloodspot normal range (n = 152) is 0–0.30 µmol/L. Bloodspots from children with hepatorenal tyrosinemia type 1, and kept at room temperature for up to 7 years, afforded SA concentrations of 0.9–5.7 µmol/L. Copyright © 2006 John Wiley & Sons, Ltd.
A novel method for the study of the biophysical interface in soils using nano‐scale secondary ion mass spectrometry
Authors: Herrmann Anke M. , Clode Peta L. , Fletcher Ian R. , Nunan Naoise , Stockdale Elizabeth A. , O'Donnell Anthony G. , Murphy Daniel V. 
Published: November 2006

AbstractThe spatial location of microorganisms and their activity within the soil matrix have major impacts on biological processes such as nutrient cycling. However, characterizing the biophysical interface in soils is hampered by a lack of techniques at relevant scales. A novel method for studying the distribution of microorganisms that have incorporated isotopically labelled substrate (‘active’ microorganisms) in relation to the soil microbial habitat is provided by nano‐scale secondary ion mass spectrometry (NanoSIMS). Pseudomonas fluorescens are ubiquitous in soil and were therefore used as a model for ‘active’ microorganisms in soil. Batch cultures (NCTC 10038) were grown in a minimal salt medium containing 15N‐ammonium sulphate (15/14N ratio of 1.174), added to quartz‐based white sand or soil (coarse textured sand), embedded in Araldite 502 resin and sectioned for NanoSIMS analysis. The 15N‐enriched P. fluorescens could be identified within the soil structure, demonstrating that the NanoSIMS technique enables the study of spatial location of microbial activity in relation to the heterogeneous soil matrix. This technique is complementary to the existing techniques of digital imaging analysis of soil thin sections and scanning electron microscopy. Together with advanced computer‐aided tomography of soils and mathematical modelling of soil heterogeneity, NanoSIMS may be a powerful tool for studying physical and biological interactions, thereby furthering our understanding of the biophysical interface in soils. Copyright © 2006 John Wiley & Sons, Ltd.
Anxiety among university students during the SARS epidemic in Hong Kong
Authors: Wong Tze Wai , Gao Yang , Tam Wilson Wai San 
Published: November 2006

AbstractA questionnaire survey was conducted during the Severe Acute Respiratory Syndrome (SARS) epidemic to assess the anxiety level and the perceived sources of stress among students from two universities where the outbreak occurred in the teaching hospital of one of the universities. The anxiety level caused by SARS in medical students at the teaching hospital was higher than in non‐medical students in the same university and lowest in students of the other university situated 20km away from the affected hospital. Copyright © 2006 John Wiley & Sons, Ltd.
Stress in New Zealand farmers
Authors: Firth H.M. , Williams S.M. , Herbison G.P. , McGee R.O. 
Published: November 2006

AbstractThis was a cross‐sectional study of stress in a stratified, random sample of New Zealand farmers (n = 1015). Data were obtained on farming‐specific environmental stressors, demographics and farm information. The stressor questionnaire grouped questions into seven sections; policy and procedures, finance, time pressures, hazards in farming, unpredictable factors in farming, geographical isolation, and community issues. The response rate was 60 per cent of farms. The most stressful events were ‘increased work load at peak times’, ‘dealing with workers’ compensation', ‘bad weather’, and ‘complying with health and safety legislation’. There were differences between men and women regarding stress experienced. Factor analysis found that the proposed model of farm‐specific stressors fitted the data moderately well. Age, being separated or divorced, being a deer farmer, the farm not making a profit in the last year, and supervising staff were independently associated with higher stress. The study highlights certain stressful factors that may be alleviated by action by farmer and government organizations as well as rural communities, including matters to do with staffing and health and safety, and financial and community support. Copyright © 2006 John Wiley & Sons, Ltd.
A qualitative study of self‐perceived effects of mindfulness‐based stress reduction (MBSR) in a psychosocial oncology setting
Authors: Mackenzie Michael J. , Carlson Linda E. , Munoz Marleny , Speca Michael 
Published: November 2006

AbstractQuantitative research has shown Mindfulness‐based Stress Reduction (MBSR) programmes can reduce mood disturbance, improve quality of life, and decrease stress symptoms of cancer patients. However, the range of subjective effects experienced by programme participants has not been clearly described. Nine cancer patients who had participated in an 8‐week MBSR programme through the Tom Baker Cancer Centre's Department of Psychosocial Resources, and who continued to attend weekly drop‐in MBSR sessions were interviewed for this study. Qualitative research was conducted using grounded theory analysis. Data from semi‐structured interviews and a focus group were analysed using QSR N6 software to identify themes concerning the effects patients experienced by adding meditation to their lives. Five major themes emerged from the data: (1) opening to change; (2) self‐control; (3) shared experience; (4) personal growth; (5) spirituality. This information was used to develop specific theory concerning mechanisms whereby MBSR effects change for cancer patients. These understandings may be used to refine and further develop MBSR programmes to better assist patients during cancer diagnosis, treatment and recovery. Copyright © 2006 John Wiley & Sons, Ltd.
Polymorphic transformation of 1,3‐distearoyl‐sn‐2‐linoleoyl‐glycerol
Authors: Takeuchi M. , Ueno A. , Yano J. , Floter E. , Sato K. 
Published: November 2006

AbstractPolymorphic transformation behavior of sub‐α1, sub‐α2, α, and γ in 1,3‐distearoyl‐sn‐2‐linoleoyl‐glycerol (SLS) has been studied with X‐ray diffraction, differential scanning caloremetry, and Fourier‐transform infrared spectroscopy. Synchrotron radiation X‐ray beam was employed to observe rapid transformation processes from the sub‐α and α forms to the γ form. The chain length structures were double in sub‐α1, sub‐α2, and α, whereas γ was of triple chain‐length structure. The subcell packing was pseudohexagonal for the two sub‐α forms, hexagonal for the α form, and parallel type for the γ form. In comparison with 1,3‐distearoyl‐sn‐2‐oleoyl‐glycerol (SOS), the occurrence behavior of sub‐α, α, and γ of SLS was the same as that of SOS. However, the absence of β′ and β was unique for SLS. The chain‐chain interactions between the linoleoyl moieties may stabilize the γ form, prohibiting the transformation into β′ and β forms. The presence of two cis double bonds may cause this stabilization, revealing the disordered chain conformation of the unsaturated chains.
Kinetics of palm oil transesterification in a batch reactor
Authors: Darnoko D. , Cheryan Munir 
Published: November 2006

AbstractMethyl esters were produced by transesterification of palm oil with methanol in the presence of a catalyst (KOH). The rate of transesterification in a batch reactor increased with temperature up to 60°C. Higher temperatures did not reduce the time to reach maximal conversion. The conversion of triglycerides (TG), diglycerides (DG), and monoglycerides (MG) appeared to be second order up to 30 min of reaction time. Reaction rate constants for TG, DG, and MG hydrolysis reactions were 0.018–0.191 (wt%·min)−1, and were higher at higher temperatures and higher for the MG reaction than for TG hydrolysis. Activation energies were 14.7, 14.2, and 6.4 kcal/mol for the TG, DG, and MG hydrolysis reactions, respectively. The optimal catalyst concentration was 1% KOH.
A kinetic study of phospholipid extraction by degumming process in sunflower seed oil
Authors: Pan L. G. , Campana A. , Toms M. C. , n M. C. A. 
Published: November 2006

AbstractDuring the refining process of vegetable oils (degumming), phospholipids are eliminated by thermal treatment with water (hydratable phospholipids, HP) and other degumming agents such as phosphoric acid, citric acid, or acid mixtures (nonhydratable phospholipids, NHP). Samples of pressed crude sunflower oils were degummed with water and acids, and the corresponding pellets (gums) and supernatant oils were obtained by centrifugation. During the water degumming process, a decrease of more than 98% in the phosphatidylcholine (PC) content was achieved in 5 min; phosphatidylethanolamine (PE) was the most difficult compound to be removed. Phosphatidylserine, phosphatidic acid, and phosphatidylinositol (PI) presented an intermediate behavior. The optimal contact time for quantitative extraction of the most important HP (PC, PI, and PE) in crude sunflower oils was 35 min. For acid treatments, a rapid elimination of the residual levels of PC was registered (5 min); the optimal contact times for the quantitative removal of the NHP were 35 min for phosphoric acid und acid mixture, and 25 min for citric acid. Taking into account that PE was the most difficult component to be removed, its level could be used as a monitor to evaluate the efficiency of the degumming process.
The development of nonchromium catalyst for fatty alcohol production
Authors: Hattori Yasuyuki , Yamamoto Katsutoshi , Kaita Jun , Matsuda Morio , Yamada Shuichi 
Published: November 2006

AbstractFatty alcohols are obtained by hydrogenation of fatty acid methyl esters derived from coconut oil and palm kernel oil. Cu−Cr has been widely used as a hydrogenation catalyst. We have developed a new environment‐friendly catalyst that could substitute for the conventional Cu−Cr catalyst, preventing the release of toxic hexavalent Cr. Here we report the development of Cr‐free, Cu−Fe−Al oxide catalyst. We found that iron has a strong promoting effect nearly equivalent to that of Cr and that the addition of Al significantly improved the reuse property (durability) through a study of trivalent metal addition to Cu. Powder X‐ray diffraction analysis of the used catalyst revealed that the Al addition suppressed the transformation of the CuFe2O4 component (Cu−Fe spinel) to α‐Fe. It was concluded that the stabilization of CuFe2O4 during reduction improved the catalyst durability. A plant‐scale experiment confirmed that the Cu−Fe−Al oxide catalyst performs as well as the conventional Cu−Cr catalyst.
Low‐temperature phase behavior of vegetable oil/co‐solvent blends as alternative diesel fuel
Authors: Dunn R. O. , Bagby M. O. 
Published: November 2006

AbstractVegetable oils (triacylglycerols) have many characteristics that make them attractive candidates as renewable alternative fuels for compression‐ignition (diesel) engines. Unfortunately, vegetable oils are too viscous to be compatible with modern direct‐injection diesel fuel systems and engines. Co‐solvent blending is a simple and flexible technology that reduces viscosity by mixing the oil with low molecular weight alcohol. A co‐solvent (A), consisting, of surfactant plus an amphiphilic compound, is added to solubilize otherwise nearly immiscible oil‐alcohol mixtures into a single‐layer (isotropic) solution. This work examines low‐temperature phase behavior of two soybean oil (SBO)/methanol mixtures solubilized by A=unsaturated long‐chain (C18) fatty alcohol/medium‐chain alkanol (n‐butanol and 2‐octanol), one SBO/methanol mixture solubilized by A=triethylammonium linoleate/2‐octanol, and one SBO/95 wt% ethanol (E95) mixture solubilized by n‐butanol. The E95‐blend was further blended in 1∶1 (vol/vol) mixtures with No. 2 diesel fuel. Two types of anisotropic phase behavior were observed; formation of a cloudy layer of solid crystals suspended in bulk solution (Type 1) and formation of two immiscible liquid layers (Type II). The type of phase separation in a given solution was influenced by phase separation temperature (Tϕ) relative to the crystallization characteristics of compounds in the SBO and fatty alcohol or amine constituents present in solution. Solutions with relatively low Tϕ values experienced crystallization of small solid particles favoring Type 1 separations. Conversely, solutions with Tϕ sufficient to avert crystallization of high melting point compounds favored Type II separations where Tϕ=critical solution temperature (Tcritical). Increasing the A/oil (SBO or No. 2 diesel/SBO mixture) mass ratio decreased Tϕ while increasing the mass fraction of alcohol (methanol or E95) increased Tϕ. This work shows that vegetable oil/A‐based blends can be formulated with cold flow properties superior with respect to cloud point and comparable with respect to kinematic viscosity (v) of methyl soyate (biodiesel), either neat or blended with petroleum middle distillates.
Characterization of triglycerides isolated from jojoba oil
Authors: Van Boven M. , Holser R. A. , Cokelaere M. , Decuypere E. , Govaerts C. , Lemey J. 
Published: November 2006

AbstractTriglyceride compounds isolated from jojoba seed oil by column chromatography were composed predominantly of C18′ C20′ C22′ and C24 n−9 fatty acids with minor amounts of saturated C16. Chain length and double‐bond positions were determined by gas‐liquid chromatography and gas‐liquid chromatography‐mass spectrometry of the corresponding methyl ester and picolinyl ester derivatives. Triglyceride structures were analyzed directly by ion trap mass spectrometry. The analysis of minor compounds, can provide highly specific information about the identity of an oil.
Determining the blend level of mixtures of biodiesel with conventional diesel fuel by fiber‐optic near‐infrared spectroscopy and 1H nuclear magnetic resonance spectroscopy
Authors: Knothe Gerhard 
Published: November 2006

AbstractBiodiesel, defined as the alkyl esters (usually methyl esters) of vegetable oils, is miscible with conventional diesel fuel at all blend levels. Until the present time, no rapid and reliable analytical method has existed for determining the blend level of biodiesel in conventional diesel fuel. In the present work, near‐infrared (NIR) and nuclear magnetic resonance (NMR) spectroscopies were used to determine the blend level of biodiesel in conventional diesel fuel. Several regions in the NIR region (around 6005 cm−1 and 4800–4600 cm−1) are suitable for this purpose. The method is rapid and easy to use, and does not require any hardware changes when using the same instrument for monitoring the biodiesel‐producing transesterification reaction and determining biodiesel fuel quality. In 1H NMR spectroscopy, the integration values of the peaks of the methyl ester moiety and the aliphatic hydrocarbon protons in biodiesel and conventional diesel fuel were used for determining blend levels. The results of NIR and NMR blend level determinations are in good agreement.
Encapsulation of sea buckthorn kernel oil in modified starches
Authors: Partanen Riitta , Yoshii Hidefumi , Kallio Heikki , Yang Baoru , Forssell Pirkko 
Published: November 2006

AbstractEncapsulation of CO2‐extracted sea buckthorn kernel oil and the stability of the products were investigated. Maltodextrin and an emulsifying starch derivative were used for encapsulation by spray drying. Both shell materials significantly increased the storage stability of sea buckthorn kernel oil, even though in maltodextrin capsules 10% of the total oil was extractable from the surface of the capsule. The cornstarch sodiium octenyl succinate derivative capsules contained essentially no surface oil. After 9 wk storage at controlled conditions (20°C, RH 50%), PV of the unencapsulated oil was above 90 meq/kg, whereas in the encapsulated oils, the PV was still around 20 meq/kg. The PV of the encapsulated oil was dependent on the storage conditions. A small increase in temperature (from 20 to 25–30°C) and a significant increase in humidity (from RH 50 to RH 50–70%) decreased the stability of capsules. This was associated with the physical state of the microcapsule matrix and may be linked with glass transition of the wall polymers.
Influence of operating variables on yield and quality parameters of olive husk oil extracted with supercritical carbon dioxide
Authors: de Lucas A. , Rincón J. , Gracia I. 
Published: November 2006

AbstractSupercritical fluid extraction is a viable alternative process for extracting oil from olive husk, a residue obtained in the olive oil production. We analyzed the effects of pressure (P) (100–300 bar), temperature (T) (40–60°C), solvent flow (1–1.5 L/min), and particle size (D) (0.30–0.55 mm) on extraction yield, and three oil‐quality parameters: acidity (OA), PV, and phosphorus content (PC). A response surface methodology based on the statistical analysis of the experimental data permitted us to obtain mathematical expressions relating the operational variables and parameters studied. At the best extraction condition of the experimental range analyzed (P=300 bar, T=60°C, D=0.30 mm, and solvent flow=1.25 L/min at standard conditions), the oil yield was 80% (w/w) with respect to hexane extraction, whereas the quality parameters OA, PV, and PC were 14% (w/w), 8 meq/kg, and 2.3·10−3% (w/w), respectively. These results were compared to those obtained by hexane Soxhlet extraction. The quality of the supercritical extract was superior, requiring only simple refining. This advantage may result in improved economics of the supercritical process in relation to the conventional extraction with hexane.
Oil fractionation as a preliminary step in the characterization of vegetable oils by high‐resolution 13C NMR spectroscopy
Authors: Zamora Rosario , Gómez Gemma , Dobarganes M. Carmen , Hidalgo Francisco J. 
Published: November 2006

AbstractOne hundred nine oil samples were separated chromatographically to obtain oil fractions with a decreased TAG content but with enhanced levels of the minor components that define oil genuineness and quality. The oils, which included virgin olive oils from different cultivars and regions of Europe and north Africa and refined olive, “lampante” olive, refined olive pomace, hazelnut, rapeseed, high‐oleic sunflower, corn, grapeseed, soybean, and sunflower oils, were fractionated on a silica gel column with hexane/diethyl ether as the mobile phase eluent. The method was highly reproducible, and the fraction obtained contained about 15% unmodified TAG and 85% polar compounds, which included polymeric TAG, oxidized TAG, DAG, MAG, and FFA, in addition to other minor polar components of the oils. The presence of these compounds, in an enriched fraction, should provide information about the thermal, oxidative, and hydrolytic alterations of the oils, as well as many compounds of interest in determining oil genuineness. The results indicate that these fractions can provide more information than the original oils for NMR or other spectroscopic studies used in the determination of oil quality.
Evolution of short‐chain glycerol‐bound compounds during thermoxidation of FAME and monoacid TAG
Authors: Berdeaux Olivier , Velasco Joaquín , Márquez‐Ruiz Glorida , Dobarganes Carmen 
Published: November 2006

AbstractMethyl heptanoate and octanoate, methyl 8‐oxooctanoate and 9‐oxononanoate, and dimethyl suberate and azelate were quantitated in model systems of FAME, i.e., methyl oleate and linoleate, and monoacid TAG, i.e., triolein and trilinolein, heated at 180°C for 5, 10, and 15h. Polar compounds, ranging from 20.2 to 53.2% in TAG systems, were also quantitated as a reference for the level of degradation of the samples analyzed. Base‐catalyzed techniques were used for methylation as they did not modify the structure of the compounds of interest. The maximum amounts of short‐chain FAME and of aldehydic FAME obtained were of the same order (3–4 mg/g sample in methyl linoleate and trilinolein heated for 15 h). After a second methylation step with diazomethane, amounts of dimethyl suberate and azelate were also quantitated. The total amounts of dimethyl esters in TAG model systems ranged from 1.07 to 3.35 mg/g of heated sample and were similar to those found for total aldehydic FAME (from 1.03 to 3.15 mg/g of heated sample), suggesting that oxidation of the aldehydic acyl group to an acid acyl group was a major reaction.
Solid lubricant formulations containing starch‐soybean oil composites
Authors: Biresaw G. , Erhan S. M. 
Published: November 2006

AbstractStarch‐oil composites comprising purified foodgrade corn starch (PFGS) and soybean oil (SBO) were investigated as potential ingredients for water‐based solid lubricant formulations. Current solid lubricants are almost exclusively petroleumbased and are used for protecting sheet metal and/or as sheet metal forming lubricants. Starch‐oil composites are preferred ingredients for formulating solid lubricants because they are based on renewable and abundantly available raw materials and also have superior environmental and health characteristics. Steel sheets coated with the PFGS‐SBO containing solid lubricant were evaluated for boundary coefficient of friction (COF) and wear properties using ball‐on‐flat test geometry. The COF was highly dependent on the SBO to PFGS ratio in the composite. In the absence of SBO, the COF was high (≈0.8) and decreased sharply with increasing SBO content to a minimum value of 0.07. Wear evaluation showed no scratches or lubricant transfer on the ball. There were also no wear tracks observed on the flat sheet before or after the solid lubricant was washed off. It was concluded that waterbased solid lubricants formulated with the PFGS‐SBO starch‐oil composite have acceptable friction and wear properties and should be evaluated further for use in sheet metal forming.
Fractionation and enrichment of CLA isomers by selective esterification with Candida rugosa lipase
Authors: Nagao Toshihiro , Shimada Yuji , Yamauchi‐Sato Yoshie , Yamamoto Takaya , Kasai Masaaki , Tsutsumi Kentaro , Sugihara Akio , Tominaga Yoshio 
Published: November 2006

AbstractA commercial product of CLA contains almost equal amounts of cis‐9,trans‐11 (c9,t11)‐CLA and trans‐10,cis‐12 (t10,c12)‐CLA. We attempted to enrich the two isomers by a two‐step selective esterification using Candida rugosa lipase that acted on c9,t11‐CLA more strongly than on t10,c12‐CLA. An FFA mixture containing CLA isomers was esterified with an equimolar amount of lauryl alcohol in a mixture of 20% water and the lipase. When the esterification of total FA reached 50%, two isomers were fractionated in a good yield: t10,c12‐CLA was enriched in FFA, and c9,t11‐CLA was recovered in lauryl esters. The FFA were esterified again to enrich t10,c12‐CLA. At 27.3% esterification of total FA, the t10,c12‐CLA content in FFA increased to 64.8 wt% with 89.3% recovery: The ratio of the content of t10,c12‐CLA to that of two isomers was 95.9%. Lauryl esters obtained by the single esterification were employed for enrichment of c9,t11‐CLA. After the esters were hydrolyzed, the resulting FFA were esterified again with lauryl alcohol. At 62.0% esterification of total FA, the c9,t11‐CLA content in lauryl esters increased to 73.3 wt% with 79.4% recovery: The ratio of the content of c9,t11‐CLA to that of two isomers was 95.6%. In a 600‐g‐scale purification, molecular distillation was effective in separating the reaction mixture into lauryl alcohol, FFA, and lauryl ester fractions.