HPTLC determination of apigenin in some Iranian liquid products ofMatricaria chamomillaL.

2006 ◽  
Vol 19 (111) ◽  
pp. 383-385 ◽  
Author(s):  
Nazli Nader ◽  
Somayeh Esmaeili ◽  
Farzaneh Naghibi ◽  
Mahmoud Mosaddegh
Keyword(s):  
2012 ◽  
Vol 260-261 ◽  
pp. 593-597
Author(s):  
Veronika Sassmanová ◽  
Zuzana Poláčková ◽  
Jaroslav Frantík ◽  
Stanislav Honus ◽  
Dagmar Juchelková

The article deals with the identification of a chemical structure of pyrolysis liquid occurring by the thermal degradation of tyre debris within the temperature interval from 500°C to 650°C and the temperature increase steps of 50°C in individual experiments and with the use of analytical methods GC/MS, FT-IR and the elementary analysis. The measured FT-IR spectra indicate the representation of functional groups included in measured samples. They could be used for the determination of basic chemical properties. There were changes in the chemical composition monitored as well as the creation of functional groups in the pyrolysis liquid on the basis of FT-IR spectra and GS/MS outcomes.


1983 ◽  
Vol 281 ◽  
pp. 101-108 ◽  
Author(s):  
F.P. Di Sanzo ◽  
J.L. Lane ◽  
P.M. Bergquist ◽  
S.A. Mooney ◽  
B.G. Wu

Author(s):  
G.M. Koloskova ◽  
V.Yu. Koloskov

Purpose: The aim of the represented study was to model the impact of temperature gradient on content of polymer ampoule during its forming. Design/methodology/approach: The model of polymer ampoules forming is built in SolidWorks software on the basis of finite element method. Using the developed model the study of temperature condition changes is carried out. Numerical modelling was carried out for two types of polymer packaging materials – polypropylene and polyvinylchloride – in similar conditions. Findings: During polymer ampoule forming the highest temperature of liquid is obtained at the bottom of it. The most effective packaging method is to form the ampoule from polypropylene by means of aluminium die. Investigation results have shown that the highest obtained liquid temperature has linear dependence from initial one. Linear coefficients of heating were evaluated for polypropylene (equal to 0.72) and polyvinylchloride (equal to 0.58). Practical implications: Decrease of initial liquid temperature value gives an opportunity to expand the range of products allowed to be packed in polymer ampoules in represented method. Safe conditions for packaging of liquid products in polymer ampoules are formulated, The results of the study may be used to improve the quality of liquid products packaging in polymer ampoules. Originality/value: For the first time the model was developed for determination of liquid heating degree during its packaging in polymer ampoules. The calculations of the temperature distribution are represented for polypropylene and polyvinylchloride ampoules forming by means of aluminium and ceramic dies. The results of the study may be of interest to specialists in the field of polymer packaging manufacturing for food or pharmaceutical industry.


2004 ◽  
Vol 87 (6) ◽  
pp. 1297-1304 ◽  
Author(s):  
Jeanne I Rader ◽  
Carol M Weaver ◽  
Mary W Trucksess

Abstract AOAC Official Method 999.14 is applicable for the determination of choline in milk and infant formulas. To date, its use has not been extended beyond these matrixes. We modified Official Method 999.14 and applied it to the determination of choline in a range of choline-containing dietary supplements. Dietary supplement tablets, capsules, wafers, softgels, liquid products, and drink powders were included. We found that the standard curve could be extended to cover a wider range of choline concentrations and defined a procedure for the use of Norit for samples in which the vitamin C content was high enough to interfere with the analysis. Recoveries of choline added to infant formula powders and to representative dietary supplement tablets, capsules, powdered drink mix, and wafer products were 85–114%. The use of Norit during the procedure did not affect the recovery of choline added to infant formula powders or to dietary supplements. An alkaline digestion was included for use with a product containing lecithin as the sole source of choline.


2014 ◽  
Vol 1004-1005 ◽  
pp. 1133-1136
Author(s):  
Ling Zhong ◽  
Jia Mei Jin ◽  
Cheng Cai Zeng ◽  
Yu Wen Yu ◽  
Dong Zhang

The determination of EG content in the liquid products of PET hydrolysis process under microwave irradiation at 170°C 180°C and 190°C was measured by Gas chromatography. The chromatographic column was quartz capillary chromatographic column the carrier gas was nitrogen hydrogen flame ionization detector FID. The result indicated that the concentration curves of EG didn’t follow a dynamic process which suggested that PET hydrolysis under microwave was not a continuous process dynamics.


2014 ◽  
Vol 97 (3) ◽  
pp. 721-730 ◽  
Author(s):  
Richard T Lamar ◽  
Daniel C Olk ◽  
Lawrence Mayhew ◽  
Paul R Bloom

Abstract Increased use of humic substances in agriculture has generated intense interest among producers, consumers, and regulators for an accurate and reliable method to quantify humic acid (HA) and fulvic acid (FA) in raw ores and products. Here we present a thoroughly validated method, the new standardized method for determination of HA and FA contents in raw humate ores and in solid and liquid products produced from them. The methods used for preparation of HA and FA were adapted according to the guidelines of the International Humic Substances Society involving alkaline extraction followed by acidification to separate HA from the fulvic fraction. This is followed by separation of FA from the fulvic fraction by adsorption on a nonionic macroporous acrylic ester resin at acid pH. It differs from previous methods in that it determines HA and FA concentrations gravimetrically on an ash-free basis. Critical steps in the method, e.g., initial test portion mass, test portion to extract volume ratio, extraction time, and acidification of alkaline extract, were optimized for maximum and consistent recovery of HA and FA. The method detection limits for HA and FA were 4.62 and 4.8 mg/L, respectively. The method quantitation limits for HA and FA were 14.7 and 15.3 mg/L, respectively.


1977 ◽  
Vol 60 (4) ◽  
pp. 799-804
Author(s):  
David M Takahashi

Abstract A previously developed high pressure liquid chromatographic (HPLC) method was evaluated by an extensive recovery study of aflatoxins from wines and other liquid products. The HPLC column and the preliminary cleanup procedures were both modified for this study. Four aflatoxins (B1, B2, G1, and G2) were recovered at 80–116% from 28 samples of various liquid commodities spiked at the 1 μg/L (1 ppb) level. The detection limit of the proposed method for wines and fruit juices was about 0.02 ppb. A total of 53 samples were analyzed for aflatoxins during this study.


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