scholarly journals Stainless-Steel Column for Robust, High-Temperature Microchip Gas Chromatography

2018 ◽  
Vol 91 (1) ◽  
pp. 792-796 ◽  
Author(s):  
Abhijit Ghosh ◽  
Austin R. Foster ◽  
Jacob C. Johnson ◽  
Carlos R. Vilorio ◽  
Luke T. Tolley ◽  
...  
2011 ◽  
Vol 2011 ◽  
pp. 1-6 ◽  
Author(s):  
F. Q. Yang ◽  
H. K. Wang ◽  
H. Chen ◽  
J. D. Chen ◽  
Z. N. Xia

A preparative gas chromatography (pGC) method was developed for the separation of volatile components from the methanol extract ofCurcumarhizome. The compounds were separated on a stainless steel column packed with 10% OV-101 (3 m × 6 mm, i.d.), and then, the effluent was split into two gas flows. One percent of the effluent passed to the flame ionization detector (FID) for detection and the remaining 99% were directed to the fraction collector. Five volatile compounds were collected from the methanol extract ofCurcumarhizome (5 g/mL) after 83 single injections (20 uL) with the yield of 5.1–46.2 mg. Furthermore, the structures of the obtained compounds were identified asβ-elemene, curzerene, curzerenone, curcumenol, and curcumenone by MS and NMR spectra, respectively.


2016 ◽  
Vol 139 (1) ◽  
Author(s):  
Byeongnam Jo ◽  
Koji Okamoto

This study aims to investigate the creep buckling behavior of a stainless steel column under axial compressive loading at extremely high temperatures. Creep buckling failure time of a slender column with a rectangular cross section was experimentally measured under three different temperature conditions, namely, 800, 900, and 1000 °C. At each temperature, axial compressive loads with magnitudes ranging between 15% and 80% of the buckling loads were applied to the top of the column, and the creep buckling failure time was measured to examine its relationship with the compressive load. The stainless steel column was found to fail within a relatively short time compared to that of creep deformation under tensile loading. An increase in the temperature of the column was found to accelerate creep buckling failure. The in-plane and out-of-plane column displacements, which respectively, corresponded to the axial and lateral displacements, were monitored during the entire experiment. The creep buckling behavior of the column was also visualized by a high-speed camera. Based on the Larson–Miller parameters (LMP) determined from the experimental results, an empirical correlation for predicting the creep buckling failure time was developed. Another empirical correlation for predicting the creep buckling failure time based on the lateral deflection rate was also derived.


1964 ◽  
Vol 45 (4_Suppl) ◽  
pp. S71-S80 ◽  
Author(s):  
John T. France ◽  
Neal L. McNiven ◽  
Ralph I. Dorfman

ABSTRACT A convenient, sensitive and reproducible method for the determination of androsterone, aetiocholanolone and dehydroepiandrosterone, as their trimethylsilyl ether derivatives, has been described. The conditions include: 3.3 % XE-60 on Anakrom ABS (90-100 mesh), 6 ft. × 3.8 mm i. d. stainless steel column, 225° column temperature, 327° vaporizer temperature, nitrogen pressure 11.0 p. s. i. (34 ml/min flow). The % variation between duplicate samples for androsterone, aetiocholanolone and dehydroepiandrosterone respectively was 1.5, 4.5 and 1.8 at the 0.3 μg level. Quantitation at the 0.05 μg level appears possible.


1974 ◽  
Vol 57 (3) ◽  
pp. 560-562
Author(s):  
Martin J Stutsman

Abstract Chloroform in toothpastes is determined by gas-liquid chromatography of the vapors in the headspace over a diluted sample, using an electron capture detector. The method is sensitive to small amounts of chloroform and avoids the injection of materials deleterious to the column. The 12' × 1/8" od stainless steel column is packed with acid-washed Gas-Chrom R coated with 2 0% Carbowax 20M. Recoveries of chloroform added to toothpastes range from 95 to 104%.


2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Amit Kumar De ◽  
Partha Pratim Chowdhury ◽  
Shyamaprasad Chattapadhyay

Quantitative estimation of resorcinol from marketed pharmaceutical formulation has been reported in this study. Resorcinol as a pharmaceutical ingredient has a broad spectrum of application but its application is limited due to its toxic side effects. Method for the accurate estimation of resorcinol is therefore essential. In the current study we have developed a chromatographic technique for its estimation from a marketed hair tonic meant for the treatment of several dermatological diseases of the scalp. A stainless steel column 25 cm in length and 4 mm internal diameter packed with octadecylsilane (5 µm) was used for this purpose. The mobile phase was a mixture of phosphate buffer of pH 2.8 and acetonitrile. The flow rate was 0.6 mL·min−1 and the detection wavelength was 280 nm. The method was found to be linear between concentration range 10.28 µg·mL−1 to 71.96 µg·mL−1 with r2 value 0.999. The accuracy of the method and the intraday and interday precession study presents the applicability of the method for the estimation of resorcinol from any pharmaceutical and cosmetic product containing resorcinol.


2019 ◽  
Vol 9 (7) ◽  
pp. 1509 ◽  
Author(s):  
Ola Svahn ◽  
Erland Björklund

Two green chemistry extraction systems, an in-house stainless-steel column Pressurized Hot Water Extraction system (PHWE) and a commercially available Espresso machine were applied for analysing 23 active pharmaceutical ingredients (APIs) in sewage sludge. Final analysis was performed on UPLC-MS/MS using two different chromatographic methods: acid and basic. When analysing all 23 APIs in sewage sludge both extraction methods showed good repeatability. The PHWE method allowed for a more complete extraction of APIs that were more tightly bound to the matrix, as exemplified by much higher concentrations of e.g., ketoconazole, citalopram and ciprofloxacin. In total, 19 out of 23 investigated APIs were quantified in sewage sludge, and with a few exceptions the PHWE method was more exhaustive. Mean absolute recoveries of 7 spiked labelled APIs were lower for the PHWE method than the Espresso method. Under acid chromatographic conditions mean recoveries were 16% and 24%, respectively, but increased to 24% and 37% under basic conditions. The difference between the PHWE method and the Espresso method might be interpreted as the Espresso method giving higher extraction efficiency; however, TIC scans of extracts revealed a much higher matrix co-extraction for the PHWE method. Attempts were made to correlate occurrence of compounds in sewage sludge with chemical properties of the 23 APIs and there are strong indications that both the number of aromatic rings and the presence of a positive charge is important for the sorption processes to sewage sludge.


2012 ◽  
Vol 235 (5) ◽  
pp. 853-859 ◽  
Author(s):  
Andrea Carrara Geöcze ◽  
Evelyn de Souza Oliveira ◽  
Katalin Carrara Geöcze ◽  
Raquel Mendonça Alvarenga ◽  
Marcus H. Canuto ◽  
...  

The Analyst ◽  
2019 ◽  
Vol 144 (21) ◽  
pp. 6327-6333 ◽  
Author(s):  
Wanwan Ma ◽  
Yena An ◽  
Kyung Ho Row

A protein-based molecularly imprinted monolithic column was synthesized based on ionic liquids (ILs) and deep eutectic solvents (DESs) in a stainless steel column (50 mm × 4.6 mm id).


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