We have developed a new inlet system for a gas sample isotope ratio mass spectrometer (IRMS). It is based on the well-known open split design from the gas chromatography/mass spectrometry (GC/MS) system due to its simplicity. The advantages over the conventional double inlet system with the metal bellows design include an improved reproducibility mainly due to a highly controllable pressure and temperature adjustment, a markedly lowered memory effect due to an uninterrupted gas flow through the ion source which limits adsorption/desorption processes on surfaces, and a single inlet capillary circumventing problems of asymmetrical behavior of sample and reference inlet paths. Furthermore, sample consumption is of the same order as for conventional measurements (i.e. about 0.4 mmol per hour), of which however only 2 &mgr;mol/h is used for the actual isotope ratio determination since the major gas amount acts as a gas flow seal against the atmosphere, corresponding to a 100-200 fold overkill. This may be improved in future systems. Copyright 2000 John Wiley & Sons, Ltd.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1002/1097-0231(20000830)14:16<1543::AID-RCM62>3.0.CO;2-H | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Physical Isolation Strategy in Multi-Layer Self-Nanoemulsifying Pellets: Improving Dissolution and Drug Loading Efficiency of Ramipril.
J Pharm Sci
January 2025
Department of Pharmaceutics, College of Pharmacy, King Saud University, POBOX-2457, Riyadh 11451, Kingdom of Saudi Arabia; Kayyali Chair for Pharmaceutical Industries, Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh 11451, Kingdom of Saudi Arabia. Electronic address:
Background And Purpose: Liquid self-nanoemulsifying drug delivery systems (SNEDDS) face challenges related to stability, handling, and storage. In particular, lipophilic and unstable drugs, such as ramipril (RMP) and thymoquinone (THQ), face challenges in oral administration due to poor aqueous solubility and chemical instability. This study aimed to develop and optimize multi-layer self-nanoemulsifying pellets (ML-SNEP) to enhance the stability and dissolution of ramipril (RMP) and thymoquinone (THQ).
View Article and Find Full Text PDFDynamic fluidic manipulation in microfluidic chips with dead-end channels through spinning: the Spinochip technology for hematocrit measurement, white blood cell counting and plasma separation.
Lab Chip
January 2025
Department of Biotechnology and Bioengineering, Izmir Institute of Technology, Izmir 35430, Turkiye.
Centrifugation is crucial for size and density-based sample separation, but low-volume or delicate samples suffer from loss and impurity issues during repeated spins. We introduce the "Spinochip", a novel microfluidic system utilizing centrifugal forces for efficient filling of dead-end microfluidic channels. The Spinochip enables versatile fluid manipulation with a single reservoir for both inlet and outlet functions.
View Article and Find Full Text PDFComputational Fluid Dynamics as a Digital Tool for Enhancing Safety Uptake in Advanced Manufacturing Environments Within a Safe-by-Design Strategy.
Materials (Basel)
January 2025
Innovation in Research & Engineering Solutions (IRES), 1000 Brussels, Belgium.
In modern manufacturing environments, pollution management is critical as exposure to harmful substances can cause serious health issues. This study presents a two-stage computational fluid dynamic (CFD) model to estimate the distribution of pollutants in indoor production spaces. In the first stage, the Reynolds-averaged Navier-Stokes (RANS) method was used to simulate airflow and temperature.
View Article and Find Full Text PDFEnhanced ensemble learning-based uncertainty and sensitivity analysis of ventilation rate in a novel radiative cooling building.
Heliyon
January 2025
Department of Energy System Engineering, Faculty of Mechanical Engineering, K.N. Toosi University of Technology, No. 15, Pardis St., Molasadra Ave., Vanak Sq., Tehran, Iran.
The rising global demand for air conditioning systems, driven by increasing temperatures and urbanization, has led to higher energy consumption and greenhouse gas emissions. HVAC systems, particularly AC, account for nearly half of building energy use, highlighting the need for efficient cooling solutions. Passive cooling, especially radiative cooling, offers potential to reduce cooling loads and improve energy efficiency.
View Article and Find Full Text PDFModelling the long-term dynamics and inhibitory effects of crude glycerol impurities in a methanogenic and sulfidogenic UASB bioreactor.
Water Res
January 2025
Department of Civil and Environmental Engineering, University of Florence, Via di S. Marta, 3, 50139, Firenze, Italy.
The performance of Upflow Anaerobic Sludge Blanket (UASB) bioreactors treating sulfate (SO) -rich effluents depends on multiple factors, including microbial interactions and operational conditions. The high complexity of these systems necessitates the use of mathematical modelling tools to better understand the process and predict the long-term impacts of various operational variables. In this work, a mathematical model describing the long-term operation of a sulfate-fed 2.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!