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Summary

Although conventional solid phase extraction (SPE) is an applicable routine method for extraction of different analytes from various matrices, it requires more time and volume of solvent and sample rather than other routine laboratory extraction methods. In this study, a rapid and simplified sample preparation method based on SPE was studied by eliminating some steps, such as conditioning and washing, for extraction of diosmin, eriocitrin, narirutin, naringin, and hesperidin in orange, tangerine, and lime juice samples. The separation of these flavonoids was achieved by using a C8 column with a mobile phase comprised of water-acetonitrile-acetic acid (78:21:1, v/v/v) at a flow rate of 0.85 mL min−1 and UV detection at 280 nm. To examine the applicability of this method, effective parameters such as type of adsorbent, type and volume of elution solvent, ionic strength, and pH of the sample were studied and applied to the comparison between the conventional SPE and the simplified method. The best recoveries were obtained, using the proposed method, with a small volume of citrus fruit juice (0.5 mL), silica gel (0.5 g) as adsorbent, and 3 mL of methanol as elution solvent. Limits of detection, limits of quantification, intra-day and inter-day precision of the method for the analytes were 0.0244–0.0587 μg mL−1, 0.0739–0.178 μg mL−1, 2.5–3.1%, and 3.1–4.8%, respectively.

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Acta Chromatographica
Authors: Liyi Li, Liming Hu, Bingbao Chen, Yanwen Dong, Zixia Lin, Zhiyi Wang, Congcong Wen, Xianqin Wang, and Shuanghu Wang

In this study, we developed a urine metabolomic method by gas chromatography–mass spectrometry (GC–MS) combination with biomedical results to evaluate the effect of activated carbon on methomyl poisoning rats. The rats were divided into four groups, methomyl group, two activated carbon treatment group, and control group. According to the biochemical results, it indicated that activated carbon treated rats could cause liver and kidney function changes. According to the urine metabolomics results, activated carbon treatment group (10 min) and activated carbon treatment group (30 min) could be distinguished from methomyl group, and activated carbon treatment group (10 min) could be separated from activated carbon treatment group (30 min) rats, which indicated that the treatment of rats by activated carbon in different time had a different effect. The results indicate that metabolomic method by GC–MS may be useful to elucidate activated carbon treated on methomyl poisoning rats.

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Acta Chromatographica
Authors: Yonghui Shen, Deru Meng, Feifei Chen, Hui Jiang, Liming Hu, Yunfang Zhou, and Miaomiao Zhang

Abstract

Sarecycline is a narrow-spectrum antibiotic for the treatment of acne, which is a chronic inflammatory disease of the hair follicle sebaceous glands. In the study, UPLC-MS/MS was used to establish a rapid and accurate analytical method. The sarecycline was determined with poziotinib as internal standard (IS) in rat plasma. An ACQUITY UPLC HSS T3 column (2.1 × 100 mm, 1.8 μm) could performe chromatographic separation with the mobile phase (methanol: water of 0.1% formic acid) with gradient elution. The ions of target fragment were m/z 488.19→410.14 for sarecycline and m/z 492.06→354.55 for poziotinib, which could quantify the electrospray ionization of positive multiple reaction monitoring (MRM) mode. The linear calibration curve of the concentration range was 1–1,000 ng/mL for sarecycline with a lower limit of quantification (LLOQ) of 1 ng/mL. The mean recovery was between 82.46 and 95.85% for sarecycline and poziotinib in rat plasma. RSD for precision of inter-day and intra-day were between 3.24 and 13.36%, and the accuracy ranged from 105.26 to 109.75%. The developed and validated method was perfectly used in the pharmacokinetic study and bioavailability of sarecycline after intravenous and oral administration in rats.

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. Among the three types of expansive cements classified the ASTM C845-04 standard [ 8 ] the high-calcium aluminate cement based one was the subject of our previous studies [ 9 , 10 ]. Our efforts focused previously on the synthesis of anhydrite–lime

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Abstract

Fly ash-based geopolymer fine aggregate is a potential replacement material for the natural river sand as it has similar physicochemical properties. This paper reports the experimental investigation of a study conducted using this fine aggregate in concrete with a focus on the properties of fresh and hardened concrete. The geopolymer fine aggregate was developed by air curing process and oven curing method. The oven curing method yielded relatively better mechanical properties in concrete specimens. The oven curing results in better behavior at later age also. Laboratory tests were conducted to ascertain the fresh concrete density, slump value, hardened concrete density, compressive strength, tensile strength, and flexural strength of the concrete specimens. The microstructure of the concrete specimens was analyzed using scanning electron microscope which indicated the agglomeration of the fly ash particles with few voids demonstrating the higher water adsorption capacity of the same. The unreacted particles noted in the microstructure later tend to merge with the lime obtained from the hydration of cement so as to develop improved later age mechanical strength. The results on mechanical properties of the concrete indicate much similar results to that of the concrete developed with the normal river sand, which confirms that the geopolymer sand is an ideal replacement choice for natural river sand.

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. [4] Gomes M. , Gonçalves T. , Faria P. ( 2016 ), Hydric behavior of earth materials and the effects of their stabilization with cement or lime: Study on repair

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. [8] Gomes M. , Gonçalves T. , Faria P. ( 2016 ), Hydric behavior of earth materials and the effects of their stabilization with cement or lime: Study on repair

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Empire: Work on the Danube Limes in Austria, Slovakia, Hungary, Romania and Bulgaria . In: Breeze , D. J . – Jilek , S . (eds): Frontiers of the Roman Empire: The European Dimension of a World Heritage Site . Edinburgh , 75 – 78 . Firnigl Anett

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A talaj elektromos vezetőképessége és a termőhelyi zónák talajtulajdonságai közötti összefüggések

Correlations between soil conductivity and soil properties of crop management zones

Agrokémia és Talajtan
Authors: Kocsis Mihály, Menyhárt László, Benő András És, and hermann Tamás

Vizsgálatunk célja az volt, hogy egy Somogyban elhelyezkedő, dombvidéki mintaterület szántóin elemezzük a mért talaj-vezetőképesség (EC) értékek és lehatárolt termőhelyi (művelési) zónák talajtulajdonságai közötti összefüggéseket. A vizsgált szántóterületek löszön kialakult, típusos Ramann-féle barna erdőtalajon és karbonátos csernozjom barna erdőtalajon helyezkednek el. Feltalajuk döntően vályog és agyagos vályog fizikai féleségű. A talaj vezetőképességét 50 és 100 cm-es talajmélységben mértük.

A mintaterület talajadatait térinformatikai állományba foglaltuk, az adatok rendezését és azok összekapcsolását az ESRI ArcGIS 10.0 programmal végeztük el. A táblák heterogenitását mutató laboratóriumi talajvizsgálatok eredményeit a mért EC értékekkel összevetettük, amelyhez az IBM SPSS Statistics 20 szoftver segítségével stepwise-típusú lineáris regressziót alkalmaztunk. A regressziókat a talajvizsgálatok csoportosításával megegyezően: alap („a” eset), bővített („b” eset) és teljeskörű („c”eset) alapján futtattuk le. A számításoknál az „a” eset a talajtulajdonságokat meghatározó fontosabb talajparaméterek (kötöttség, humusz- és mésztartalom, kémhatás), a „b” eset az alap talajparamétereket és a makro tápanyagok (NPK ellátottságot), valamint a „c” eset az előző kettőt és mikro tápanyagok (Mg2+, Na+, Zn2+, Cu2+, Mn2+, SO4 2–, Fe2+ + Fe3+) körét jelenti.

A különböző csoportosításban elvégzett elemzések során arra voltunk kíváncsiak, hogy a vizsgálati talajparaméterek körének változtatásával szorosabb kapcsolatokat találunk-e a mért átlagos EC értékek és a talajtulajdonságok között. Az eredményeink által kaphatunk-e olyan kellő pontosságú és megbízhatóságú becslőmodellt, amely a talajok térbeli heterogenitását megmutatja az EC értékek alapján, így a módszer nagyban meggyorsíthatja és leegyszerűsítheti a „hagyományos” talajvizsgálatokhoz képest a termőhelyi zónák elkülönítését.

A vizsgálati eredményeink alapján elmondható, hogy mindhárom regressziós csoportosítás esetén a tengerszint feletti magasság csökkenésével arányosan nő a talaj-vezetőképesség, illetve az EC értékek növekedésével nő a talajok kötöttsége, amellyel együtt növekszik az agyagtartalom is. Ez a folyamat 100 cm-es talajmélységben a nagyobb víztartalom miatt erőteljesebben jelentkezik, mint az 50 cm-es talajmélységben. A termőhelyi zónák termékenységi viszonyait az elsődleges talajtulajdonságokon, illetve a makro és a mikro tápanyag-ellátottságokon kívül a domborzati viszonyok is módosíthatják. A talajellenállás mérése bárki számára elérhető, gyors és egyszerű módszer. A laboratóriumi talajvizsgálatokat kiegészítve alkalmas arra, hogy a precíziós növénytermesztésben segítséget nyújtson a termőhelyi zónák lehatárolásában.

Our aim was to analyse the relationships between the measured soil electrical conductivity (EC) and the soil properties of different delimited production (tillage) zones in a hillside sample area situated in Somogy county. The examined arable lands are situated in typical Ramann-type brown forest soil and chernozem-brown forest soil mostly with loam and clay loam formed on loess. For the investigations, two soil resistance values (measured at 50 cm and 100 cm depth) were used.

Soil data of the sample area were incorporated into a GIS file, the ordering and connection of the data was performed by ESRI ArcGIS 10.0 program. The results of the soil laboratory tests (which show soil heterogeneity) were correlated to the measured EC-values with stepwise linear regression using IBM SPSS Statistics 20 software. The regression were run in line with the alignment of soil investigations: basic (case „a”), extended (case „b”) and completed (case „c”). By the calculations, case „a” means the group of the most important soil parameters which are determinative soil characteristics (upper limit of plasticity or KA, humus-, lime content, pH), case „b” means the previous one plus the group of macronutrients (NPK-content), while case „c” means case „b” plus the group of micronutrients (Mg2+, Na+, Zn2+, Cu2+, Mn2+, SO4 2–, Fe2+ + Fe3+).

With the analyses made in different alignments our aim was to determine whether with the changing of examined soil parameters there will be tighter relationships between the measured EC-values and soil properties. Further aim was to examine whether it is possible to make a properly accurate and reliable estimation model, which can show the real soil circumstances (spatial heterogeneity of soils) based on EC-values, since this method can accelerate and simplify the separation of productivity zones compared to the conventional soil examinations.

Based on the results it can be concluded that in case of all the three regression groups the electrical conductivity increases proportionally with the decreasing of elevation. Besides, with the increasing of EC-values the KA – and with it, the clay content also – increases. This process develops in a more significant way in the depth of 100 cm than in 50 cm because of the higher water content. Besides the primary soil characteristics and the amount of macro- and micronutrients, the fertility conditions of the production zones can be affected by the geographical circumstances as well. The measurement of soil resistance is a fast, easy and generally available method, which is suitable – with the completion of laboratory examinations – for giving assistance to delineate the production zones in the precision crop production.

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the European medical science. [Avicenna „Kánon”-ja és az európai orvostudomány.] Ponticulus Hungaricus, 2013, 17 (10). Available from: http://members.iif.hu/visontay/ponticulus/rovatok/limes

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