Séminaires vidéo

Cement Clinkers are an intermediate product in the production of Portland Cement, one of the key ingredients in the manufacturing of concrete. Microscopic examination and analysis of Clinkers is a Quality Assurance process that assesses the nature and quality of Clinker constituents. This Webinar will discuss the process of sample preparation, microscopic examination, and the assessment of Cement Clinkers.

Determination of carbon and nitrogen in construction materials plays an important role in maintaining quality and durability of these products. This webinar will focus on this application using both the LECO CN928 and the C832. Data will be presented from a wide range of materials used in the construction industry. | Presented by Fred Schultz, Applications Chemist

Thermogravimetric analysis (TGA) is a widely used technique for Moisture or Loss on Ignition (LOI) determination in various materials. This webinar will explore enhancements in the method technique to characterize mass loss in specified materials using LECO TGA instruments. The methods discussed will include Split Loss in Cement, LOI in Combustion Residues following ASTM D7348, LOI in Flue Gas Desulfurization Solids following ASTM D8339 and Moisture and LOI in Hydrated Lime. | Presented by Jeffery Gast, Lead Analytical Chemist

This webinar will review the application of the LECO SC832 family for the determination of sulfur and carbon in a wide variety of construction materials. Sample types covered in this presentation include cement, fly ash and ore materials. In addition, the basic operating principles will be covered as well as software features that can be used to simplify the analysis and reporting of results. | Presented by Lloyd Allen, Ph.D., Director Technical Services Laboratory

Improved sensitivity and group-type selectivity makes GC×GC ideal for MOSH/MOAH separations - saturated species can be separated from the unsaturated or aromatic ones. Hans-Gerd Janssen, University of Wageningen, Netherlands.

Utilizing Gas Chromatography-Olfactometry (GC-O) can help identify active odor compounds in complex mixtures. But, what happens if GC-O does not identify a compound, but an off-flavor or malodor is still present?

Dave Coulston discusses what benefits can be derived from the different weld examinations and how best to prepare welds for such analyses, as well as typical weld measurements and examples of automated hardness testing of welds.

The American Welding Society (AWS) method A4.4M:2001 (R2006) “Standard Procedures for Determination of Moisture Content of Welding Fluxes and Welding Electrode Flux Coatings” outlines the appropriate methodology for sample preparation and analysis for this application. Moisture content in the flux can be correlated to the hydrogen content in the weld metal, and to varying degrees, the potential for hydrogen embrittlement. Clearly, determination of moisture content in welding flux is necessary to understand the quality of the final weld. Join us to learn how the LECO RC612 can be utilized to quantify the moisture present in welding flux samples, as outlined by AWS A4.4:2001 (R2006). Adam Darling, Analytical Chemist, LECO Corporation

Precise measurement of carbon in carburized steel can be challenging due to changing concentrations throughout the hardened case of a sample. Glow discharge spectroscopy (GDS) offers a repeatable ability to measure carbon in a region spatially discrete from organic carbon on the near surface and in the base material. The presentation includes comparisons to other measurements, relationships to microhardness measurements, and characterization of the materials with GDS compositional depth profiles and bulk analyses. Andrew Storey, Field Sales Specialist, LECO Corporation

Many steel components can benefit from surface hardening, which improves wear resistance while maintaining a part’s toughness. Surface hardening can be accomplished by nitriding, induction hardening, or even shot peening; but carburizing remains the most viable choice for many applications. In this webinar, Dave Coulston explains what carburizing is, how it is accomplished, and then describes the important chemical, metallurgical and mechanical property results of a carburizing treatment. This is followed by metallographic preparation of carburized steel and microscopic evaluation of the carburized layer.

The Czech Agriculture and Food Inspection Authority has been using GCxGC-TOFMS for the analysis of pesticide residues in food of plant origin since 2005. Radim Stepan will talk about the advances in the instruments and the analyses they have used for pesticide residue analysis in cooperation with the University of Chemistry and Technology Prague.

The current analytical method for the quantitative determination of Mineral Oil Saturated Hydrocarbons (MOSH) and Mineral Oil Aromatic Hydrocarbons (MOAH) is LC-GC-FID, but the chromaticagraphic profile obtained is too often just a hump of unresolved substances. However, GCxGC-TOFMS/FID is the most promising solution to characterize MOSH and MOAH in detail and to detect markers that can help identify and act on the source of contamination. Giorgia Purcaro [University of Liege] will introduce the challenges of MOSH/MOAH analysis and talk about what adding a GCxGC-TOFMS analysis to your process can do for your results.

Combustion techniques for determining nitrogen/protein in foods is gaining popularity due to shorter analysis times, ease of operation, and improved safety characteristics, but it is limited by the amount of sample an instrument is capable of analyzing at one time. Low-level nitrogen samples present a challenge to analyze due to sample characteristics and method limitations. Lloyd Allen, from LECO, will be discussing how to optimize methods for low-level nitrogen determination with combustion instruments.

One of the most common moisture determination methods is a manual mass loss on drying using an air oven following the AOAC Moisture in Meat Method (950.46). Lloyd Allen will talk about how an automated thermogravimetric moisture instrument, such as the TGM800, meets the AOAC Official Method's requirements for sample mass, oven temperature, and air flow requirements while also reducing operator and analysis times, improving precision and workflow efficiency.

The AOAC Official Method (925.10) Solids (Total) and Moisture in Flour utilizes a manual, air oven, loss-on-drying technique that is widely used in the food industry. AOAC Official Method (923.03) Ash in Flour also utilizes a manual, air oven, loss-on-drying technique. Learn from Jeffery Gast how an automated thermogravimetric moisture determination instrument like the TGA801 can follow both of the AOAC Official Methods' requirements for oven temperature and airflow while also reducing operator and analysis times, improving workflow efficiency.

Lorne Fell [LECO] provides an update on LECO Separation Science instruments and equipment. Jean-François Focant [University of Liège] presents "Multiclass GCxGC Method for Cannabis Products", discussing how GCxGC can be utilized to study cannabis strains for CBD content.

Rob Synovec [University of Washington] discusses discovery-based analysis and its application into gas chromatography, and the development of ChromaTOF® Tile, a tile-based fisher ratio analysis tool. [Synovec presentation begins at 14:00]

Liz Humston-Fulmer [LECO] utilized GCxGC TOF-MS technologies to understand the chemical composition of CBD-infused beverages. Originally presented 26 March 2020.

Dave Alonso explores GCxGC TOFMS analysis of cannabis samples for understanding of terpene and cannabinoids among cannabis cultivars.

LECO Applications Chemist, Liz Humston-Fulmer, discusses the Retention Index functionality of ChromaTOF GC-MS data analysis software. This webinar was part of the LECO 2020 GCxGC Symposium.