A soil-column gas chromatography approach was developed to simulate the mass transfer process of hydrocarbons between gas and soil during thermally enhanced soil vapor extraction (T-SVE). Four kinds of hydrocarbons-methylbenzene, n-hexane, n-decane, and n-tetradecane-were flowed by nitrogen gas. The retention factor k' and the tailing factor T f were calculated to reflect the desorption velocities of fast and slow desorption fractions, respectively. The results clearly indicated two different mechanisms on the thermal desorption behaviors of fast and slow desorption fractions. The desorption velocity of fast desorption fraction was an exponential function of the reciprocal of soil absolute temperature and inversely correlated with hydrocarbon's boiling point, whereas the desorption velocity of slow desorption fraction was an inverse proportional function of soil absolute temperature, and inversely proportional to the log K OW value of the hydrocarbons. The higher activation energy of adsorption was found on loamy soil with higher organic content. The increase of carrier gas flow rate led to a reduction in the apparent activation energy of adsorption of slow desorption fraction, and thus desorption efficiency was significantly enhanced. The obtained results are of practical interest for the design of high-efficiency T-SVE system and may be used to predict the remediation time.
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http://dx.doi.org/10.1007/s11356-015-5255-3 | DOI Listing |
J Clin Microbiol
January 2025
Department of Mycobacteriology, Leprosy Research Center, National Institute of Infectious Diseases, Higashimurayama, Tokyo, Japan.
, a slow-growing nontuberculous mycobacterium, causes Buruli ulcer, a neglected tropical disease. Distinguishing from related species, including , poses challenges with respect to making accurate identifications. In this study, we developed a rapid and simple identification method based on mycobacterial lipid profiles and used matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) to analyze the lipid profiles of ( = 35) and ( = 19) isolates.
View Article and Find Full Text PDFJ Mass Spectrom
February 2025
Center for Bioinformatics and Computational Biology, University of Delaware, Newark, Delaware, USA.
The development of a real-time system for characterizing individual biomolecule-containing aerosol particles presents a transformative opportunity to monitor respiratory conditions, including infections and lung diseases. Existing molecular assay technologies, although effective, rely on costly reagents, are relatively slow, and face challenges in multiplexing, limiting their use for real-time applications. To overcome these challenges, we developed digitalMALDI, a laser-based mass spectrometry system designed for single-particle characterization.
View Article and Find Full Text PDFInt J Pharm
January 2025
School of Pharmacy, Guilin Medical University, Guilin, Guangxi 541199, China. Electronic address:
Alprazolam (Alp), a triazolobenzodiazepine, is widely prescribed for the treatment of sleep disorders, anxiety, and panic disorder. While oral administration remains the standard route, its slow onset of action has prompted interest in intranasal delivery as an alternative, offers the potential for direct drug delivery to the brain. This study aims to develop a fast-acting intranasal formulation of Alp (Alp-nd).
View Article and Find Full Text PDFPlants (Basel)
December 2024
Institut für Angewandte Wissenschaft, Ausbau 5, 18258 Rukieten, Germany.
Phosphate (P) is the plant macronutrient with, by far, the lowest solubility in soil. In soils with low P availability, the soil solution concentrations are low, often below 2 [µmol P/L]. Under these conditions, the diffusive P flux, the dominant P transport mechanism to plant roots, is severely restricted.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
The College of Forestry, Beijing Forestry University, 100083, Beijing, PR China. Electronic address:
This study aims to address the challenge of detoxifying ginkgolic acid and transform it from waste into a valuable resource. By using pseudo-template molecular imprinting technology to chemically modify polysaccharide materials, we developed a polysaccharide-based molecular imprinted material (MMCC-CD/CS-MIP) for the targeted separation and controlled release of ginkgolic acid. Under optimal conditions, MMCC-CD/CS-MIP demonstrated excellent adsorption performance (Q = 47.
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