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. Experimental part Materials PET and PC were supplied by Mossi & Ghisolfi Group and GE Plastics South America, respectively. The PET’s melt flow rate (33.0 g/10 min) and density (1.39 g cm −3 ) were determined according to American

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Abstract  

Several chromatographic methods have been used for determining the radiochemical purity of99mTc-phytate. Good separation of99mTc-phytate from radiochemical impurities was performed using gel column chromatography packed with Sephadex G-10. Reduced99mTc-complexes and99mTc-phytate were not separated by paper and thin layer chromatography.

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The scope of NDP can be expanded by measuring (via time-of-flight) the kinetic energies of the recoils emitted from (n,p) or (n,) reactions. When they occur inside a solid, the energies of the emerging recoils reveal depth from which they originated. The Recoil Nucleus Time-of-Flight NDP (RN-TOF-NDP) technique can reveal the depth distribution of some isotopes (e.g.,10B,210Bi) with a resolution of a few Å. Furthermore, it is possible to detect atomic and molecular species ejected at the surface site where the recoil emerges from the solid. This paper discusses the methodology for RN-TOF-NDP and its applications including surface analysis based on atomic and molecular ions codesorbed with the recoils.

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A simple, rapid, and sensitive high-performance thin-layer chromatographic method has been developed and validated for analysis of residues of imidacloprid, fenitrothion, and parathion in Chinese cabbage. The sample was extracted by sonication in an ultrasonic water bath with acetone-petroleum ether, 5:3 ( v / v ), and the extract was directly applied, as bands, to glass-backed silica gel 60F 254 HPTLC plates. The plates were developed with hexane-acetone, 7 + 3 ( v / v ), in an unsaturated glass twin-trough Camag chamber. Evaluation of the developed HPTLC plates was performed densitometrically with a Camag TLC Scanner 3 controlled by an external PC running Wincats software (Version 1.1.2). The results indicated that the detection limits of imidacloprid ( R F = 0.10), fenitrothion ( R F = 0.59), and parathion ( R F = 0.70) were 5.0 × 10 −9 g, 2.0 × 10 −8 g, 1.0 × 10 −8 g, respectively. Recoveries of the pesticides from Chinese cabbage by use of this analytical method were 80.04–85.22%, and RSD were 4.18–13.15%. The precision and accuracy of the method were generally fit for analysis of pesticide residues in Chinese cabbage.

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Abstract  

Studies were initiated to investigate the effect of the delivery mode of45Ca ions through guinea pig skin in vivo. Direct current (DC), pulsating current (PC) and a Bernard current form, the “courtes periodes” current profile (CP) were applied with the same current density (0.16 mA/cm2) and for the same duration (30 minutes). The45Ca ions were delivered from a Ca-bentonite patch radiolabeled with45Ca (a natural mineral clay rich in calcium, 50 mgCa/g). The total quantity of applied bentonite was 1.5g×10 days=15g.45Ca was counted in different biological samples of the animals. The delivery of45Ca ions into the body (systemic effect) is the highest when CP current is applied (6.87±0.95·10−12g/samples). The local effect appears to be more effective in case of DC current mode (5.89±0.12·10−12g/0.5g bone). Total calcium measurements proved that the result of transdermal radiocalcium delivery is not only an ion exchange process at the surface of the bone but a deposition of calcium ions into the hydroxiapatite matrix (the net calcium introduction, which represent the difference between the total calcium into the treated bone and total calcium into untreated bone varied from 15.52±2.42·10−3g/0.5g bone to 44.30±3.50·10−3g/0.5g bone). The results suggest that iontophoresis could be used to accumulate calcium into different target tissues using the appropriate current system.

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Sample mass/mg Water/mg Water mmol/g 10 −2 n -butanol/mg n -butanol/mmol/g 10 −2 Toluene/mg Toluene/mmol/g

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Enterobacteriaceae /g m : <0.3, M : <10 Moulds /g <10 Yeasts

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(PP4) produced by PKN Orlen (Poland) were used in this study. They were characterised by the following MFR indices: 2.4–3.2 g/10 min for Malen F-401, 11–16 g/10 min for Malen P S-702, 25 g/10 min Moplen HP-548R and 50 g/10 min for Moplen HP-648T

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Super saturation ratio S = C / C * 303 K 308 K r */m (Δ G *)/10 −15 kJ

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A szerzok laboratóriumi talajérleléses kísérletet állítottak be meszes Duna öntéstalajon különbözo elemi kén dózisok (0,1 g; 1,0 g; 2,5 g; 5,0 g; illetve 10 g/tenyészedény, azaz 50, 500, 1250, 2500 és 5000 kg ha-1) talajbeli oxidációjának vizsgálata céljából mutrágyázatlan, illetve NPK-mutrágyázott körülmények között. A 84 napos inkubációs periódus elteltével a talajok pH(H2O),pH(KCl) értékeit, valamint a talajokban mérheto, vízoldható szulfátion-koncentrációt elemezték. Az eredményeket varianciaanalízis és regressziószámítás segítségével értékelték.  Az elvégzett vizsgálatok alapján megállapították, hogy a mutrágyázatlan talajok különbözo elemi kén adagok hatására kialakult pH-értékei szignifikáns különbséget nem mutattak, míg a mutrágyázott kezelések esetén az emelkedo kéndózisok hatására bekövetkezo pH-csökkenés 0,1 %-os szignifikancia szinten általánosnak bizonyult. A talajok felveheto szulfátion-koncentrációja vélhetoen a kezelések, valamint a talajok mikrobiális tevékenységének hatására minden esetben nott. Az elemi kén adagok, valamint a talajok mért szulfátion-koncentrációinak 0,1 %-os szignifikancia szinten érvényesülo összefüggései azonban a talaj pH-értékeinek alakulásával bizonyítható kapcsolatot nem mutattak. A látszólagos ellentmondás hátterében számos biológiai, fizikai és kémiai tényezo állhat, melyek meghatározása a kapott összefüggések tisztázása szempontjából további vizsgálatok szükségességét veti fel.

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