A direct resistive-heating fast temperature programming device for fast gas chromatography was designed and evaluated. A stainless-steel (SS) capillary column acted both as a separation column and as a heating element. A fast temperature controller with the deviation derivative proportional-integral-derivative (DDPID) control algorithm, which was suitable for ramp control using ramp-to-setpoint function, was used to facilitate the fast pulse heating. The SS resistive-heating column can generate linear temperature ramps up to 10 degrees C/s and can re-equilibrium from 250 degrees C down to 50 degrees C within 30s. With n-alkanes as the test analytes, the relative standard deviations (RSDs) of retention time were between 0.19 and 0.59% and the RSDs of their peak areas were less than 4% for all but one. The results indicated that this technique could be used for both qualitative and quantitative analysis. Phenolic and nitroaromatic compounds were also analyzed by using the SS resistive-heated system. The combination of a short narrow-bore SS column and rapid heating rates provides sufficient separation efficiency for relatively simple mixtures at drastically reduced analysis time. The total analysis time including equilibration time was less than 2 min for all test mixtures in this study.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.chroma.2007.08.063 | DOI Listing |
Ann Med
December 2025
Department of Laboratory Medicine, The Women's Hospital of Zhejiang University School of Medicine, Hangzhou, China.
Objective: The process of glycolysis from blood collection to centrifugation impacts the diagnosis of gestational diabetes mellitus (GDM). However, the specific characteristics of the working environment in China and its influence on GDM diagnosis still need to be clarified.
Methods: Firstly, 15 pregnant women were recruited, and six specimens were collected from each in a fasting state.
Nucleic Acids Res
January 2025
Department of Physics, 845 W Taylor St, University of Illinois Chicago, Chicago, IL 60607, USA.
Altered DNA dynamics at lesion sites are implicated in how DNA repair proteins sense damage within genomic DNA. Using laser temperature-jump (T-jump) spectroscopy combined with cytosine-analog Förster Resonance Energy Transfer (FRET) probes that sense local DNA conformations, we measured the intrinsic dynamics of DNA containing 3 base-pair mismatches recognized in vitro by Rad4 (yeast ortholog of XPC). Rad4/XPC recognizes diverse lesions from environmental mutagens and initiates nucleotide excision repair.
View Article and Find Full Text PDFFASEB J
January 2025
Department of Radiology, C.J. Gorter MRI Center, Leiden University Medical Center, Leiden, The Netherlands.
Brown adipose tissue (BAT) is a metabolically highly active tissue that dissipates energy stored within its intracellular triglyceride droplets as heat. Others have previously utilized MRI to show that the fat fraction of human supraclavicular BAT (scBAT) decreases upon cold exposure, compared with baseline (i.e.
View Article and Find Full Text PDFSensors (Basel)
January 2025
Laboratory of Sensors/Actuators and Energy Harvesting, National Institute for Research and Development in Electrical Engineering ICPE-CA, 030138 Bucharest, Romania.
The use of hydrogen as fuel presents many safety challenges due to its flammability and explosive nature, combined with its lack of color, taste, and odor. The purpose of this paper is to present an electrochemical sensor that can achieve rapid and accurate detection of hydrogen leakage. This paper presents both the component elements of the sensor, like sensing material, sensing element, and signal conditioning, as well as the electronic protection and signaling module of the critical concentrations of H.
View Article and Find Full Text PDFSensors (Basel)
January 2025
Department of Electrical and Electronics Engineering, Faculty of Engineering, Karadeniz Technical University, Trabzon 61080, Türkiye.
Electric heaters are widely used owing to their portability, fast heating, single-focus heating, and energy efficiency advantages. Manufacturers provide customers with information on the power consumption and energy efficiency classes of heaters but do not provide any information on heating patterns. Knowing the heating pattern enables users to select the correct heater, which has a significant effect on comfort, health, energy efficiency, industrial process performance, plant growth, and climate change.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!