The method comprises the screening of two groups of anabolic compounds, the stilbenes and several steroids. All compounds, inclusive their metabolites when possible, for which gas chromatography-mass spectrometry (GC-MS) currently is the preferred analytical technique, are included. Two different derivatives are prepared. One group, including the stilbenes, is detected as HFB derivative (Method 1), the second group is detected as TMS derivative (Method 2). The method is used to perform a qualitative and semi-quantitative analysis of a minimum package of anabolic steroids to be included in National Residue Control Plans based on Council Directive 96/23 and complies with the current Minimum Required Performance Limits. The method has been validated according to Commission Decision 2002/657/EC. The CCalpha and CCbeta values are based on the detection of the most abundant ion. Results of validation experiments are presented. The method is flexible and due to the non-specific sample clean-up more and new anabolic compounds can be easily added in order to new monitoring requirements.
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http://dx.doi.org/10.1016/j.aca.2006.11.056 | DOI Listing |
Micromachines (Basel)
November 2024
School of Mechanical Engineering, Shandong University of Technology, Zibo 255049, China.
The assembly and position adjustment of micro-components have wide applications in micro-electromechanical systems, wafer packaging and biomedicine. However, current single-finger microgrippers only allow for the pickup and release of micro-components. In the present study, a three-finger capillary microgripper was developed to pick up, release and adjust the position of micro-components.
View Article and Find Full Text PDFJ Mol Model
January 2025
School of Chemistry & Chemical Engineering, Linyi University, Linyi, 276000, China.
Context: In this work, a comparative study on the catalytic conversion of 5-hydroxymethyl furfural (HMF) to 2,5-bis(hydroxymethyl)furan (BHMF) on precious Pd(111) and nonprecious Cu(111) was systematically performed. On the basis of the calculated activation energy (E) and reaction energy (E), the optimal energy path for the hydrogenation of HMF (F-CHO) into BHMF (F-CHOH) on Pd(111) is as follows: F-CHO + 2H → F-CHOH + H → F-CHOH; the minimum reaction path on Cu(111) is F-CHO + 2H → F-CHO + H → F-CHOH. On Cu(111), the formation of F-CHOH from F-CHO hydrogenation is the rate-determining step because it has the highest reaction energy barrier and the smallest rate constant.
View Article and Find Full Text PDFFront Public Health
January 2025
Department of Human Nutrition, College of Medicine and Health Sciences, Debre Markos University, Debre Markos, Ethiopia.
Background: Developmental delay is a group of disorders that cause common deficits of adaptive and intellectual function in children. It happens when a child fails to achieve one aspect of developmental skills. Limited information is available regarding the prevalence of developmental delay among children aged 12-59 months in the study area.
View Article and Find Full Text PDFPLoS One
January 2025
Department of Electrical Power and Machines Engineering, Higher Institute of Engineering (HIE), El-Shorouk Academy, El-Shorouk City, Egypt.
Enhancing the performance of 5ph-IPMSM control plays a crucial role in advancing various innovative applications such as electric vehicles. This paper proposes a new reinforcement learning (RL) control algorithm based twin-delayed deep deterministic policy gradient (TD3) algorithm to tune two cascaded PI controllers in a five-phase interior permanent magnet synchronous motor (5ph-IPMSM) drive system based model predictive control (MPC). The main purpose of the control methodology is to optimize the 5ph-IPMSM speed response either in constant torque region or constant power region.
View Article and Find Full Text PDFJ Mol Model
January 2025
Department of Theoretical Chemistry, Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387, Krakow, Poland.
Context: The analysis of the changes in the electronic structure along intrinsic reaction coordinate (IRC) paths for model reactions: (i) ethylene + butadiene cycloaddition, (ii) prototype SN2 reaction Cl + CH3Cl, (iii) HCN/CNH isomerization assisted by water, (iv) CO + HF → C(O)HF was performed, in terms of changes in the deformation density (Δr) and the deformation of MEP (ΔMEP). The main goal was to further examine the utility of the ΔMEP as a descriptor of chemical bonding, and to compare the pictures resulting from Δr and ΔMEP. Both approaches clearly show that the main changes in the electronic structure occur in the TS region.
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