slide10.jpg
Filter

What is Coal?

Published Date

Coal is a combustible sedimentary rock composed mostly of carbon and hydrocarbons. It is a natural resource that is used to produce energy, both in the form of heat and electricity, but it is a non renewable resource.

The energy in coal comes from the energy stored by decayed matter. Over time, millions of years, dead plant matter is covered by layers of water and dirt that traps this energy. The heat and pressure from the top layers, undergoing chemical and physical changes, transforms these remains into coal. Coal is a complex resource and can vary in composition even within the same deposit. Each type or ranking level of coal has different energy outputs, generally as a result of increased pressurization, heat, and time. The main coal categories are, low-rank (lignite), low-rank (sub-bituminous), medium-rank (bituminous) and high-rank (anthracite).

Rebranding our Corporate Identity

Published Date

Why a new corporate identity for UIS?

For many years the analytical services of UIS stood out in the market in terms of quality, price and turn-around time. In the last 2 years or so our staff had to concentrate on handling large projects for major players in the coal mining industry and we have done extremely well in terms of turn-around time and quality.

This has also resulted in the procurement of several new instruments and the development and adoption of new methods, mainly ISO methods, but also the expansion into analytical fields, which previously formed only a minor part of our daily work. This expansion has lead to the following major reasons for the change of our corporate identity:

  1. portray a new image of our company, especially a positive first impression
  2. build a preference for our company
  3. educate our customers on who we are and keep us in the top of our customers' minds

The Cause of Sampling Errors

Published Date

Be sure a representative analytical sample is analysed by the laboratory.
Sampling errors arise both in the initial sample taking (the owner) and by reducing this bulk to a small representative sub-sample (the laboratory analyst) for analysis.
The taking of the original sample is usually not under the analyst’s control, but taking of a representative sub-sample certainly is, and it is important not to introduce unnecessary errors at this point.

Sample Preparation - Fusion Bead

Published Date

The Key to Analyses - Sample Preparation:
Sample preparation is by far the most important step in any analytical technique. The quality of the sample preparation will affect the ability to yield accurate data from the instrument. X-ray fluorescence is not immune to this crucial step, despite the ability to correct for standard counting errors, instrument variation errors, operational errors, and matrix effects.   Therefore selection of the correct sample preparation technique will depend on the goals of accuracy and precision the analyst needs or wishes to attain.

Ceramic Building Materials

Published Date

Common bricks are made from a variety of clays where clays are defined as hydrous aluminum silicates ordinarily containing impurities such as potassium, sodium, calcium, magnesium or iron.
A fireclay brick would have a plasticity of 24-26% with shrinkage after firing within 6-8%. From a chemical perspective, the Fe2O3 content is ideally less than 25%.

Pesticides by the QuEChERS Method

Published Date

We are proud to announce our successful completion of the R & D phase in pesticide analysis and are now ready to analyse your water, soil, food, fruit and vegetable samples.
PROBLEMS ASSOCIATED WITH PESTICIDES
About 60 years ago, when DDT and other organochlorine pesticides became popular in agriculture, they were considered a safe and effective way to get rid of pests. But over the years, more and more problems associated with the use of pesticides have shown up. Major problems include:
Health risks
Environmental hazards
Loss of biodiversity
Wildlife deaths
Animal and livestock deaths
Interference with natural pest control
Resistance among pests
Unwanted imports
Obsolete and unusable stocks
Residues in food
Water pollution
High input costs
TOXICITY FOR NON-TARGET ORGANISMS
Because pesticides are poisonous they will not only kill target organisms, but also impose a risk on:
The users of the pesticides
Farmers and their family members run the highest risks. They can easily come in contact with the pesticides, for example when mixing the chemicals or when applying them to the crop. 
The consumers of farm products.
The pesticides that were sprayed on the crop can leave behind residues that will be eaten by the consumers.
The environment.
Pesticides will not only reach the target organisms but will also kill other organisms (e.g. beneficial insects, birds, earthworms, fish) in or around the crop fields, causing loss of biodiversity, deaths of wild life, and death of farm animals. Soil, air and water bodies can easily be contaminated with these poisonous chemicals. The unavoidable destruction of beneficial insects and spiders interferes with natural pest control.
SOLVING THE PROBLEMS
UIS-AS envisage to assist government regulators, policy makers, farmers, NGOs, development and environment organisations, trade unions, consumers, journalists and the public to help solve pesticides problems, by offering an analytical service. This service will provide useful information in order to:
Eliminate the hazards of pesticides
Reduce dependence on pesticides and prevent the unnecessary use thereof
Increase the sustainable and ecological  alternatives to chemical pest control
UIS-AS uses the QuEChERS method that was developed by Anastassiades et. al. The method is designed to be:
Quick (a single technician can prepare 10 GC ready extracts in under an hour)
Easy (multiple transfers and manipulations of the sample are eliminated)
Cheap (the cost of materials is low)
Effective (gives good recoveries of a wide range of pesticides)
Rugged (the method can be repeatably performed after simple training)
Safe (our laboratory solvent usage for pesticide analysis is reduced by 90%+)
The method is suitable for the analysis of many products, for example maize, corn, fruit, vegetables, honey, spices, dried fruit, etc. The laboratory can also analyze for pesticides in environmental samples such as groundwater, surface water, soil and atmospheric air.

Forensic Arson Analyses: ASTM E1618

Published Date

FIRE DEBRIS (ARSON) ANALYSES NOW OFFERED BY UIS-AS
An important, and indeed the most well known, role of the forensic scientist is helping the courts to prove the existence of a crime. A critical requirement in arson analysis is that the results are definitive and legally defensible, for this reason it is crucial that the analytical techniques employed are extremely sensitive.
Despite developments in science with regards to new technology and methods, it is becoming increasingly difficult to satisfy these accelerative and stringent prerequisites. In this endeavor, the forensic scientist must focus on the following three important levels of the forensic examination process:
The chain of custody
The quality-assurance control, and
The interpretation of evidence.
Chain of custody
Debris is collected at the scene by the arson investigator and submitted to the lab for chemical analysis. The purpose of the chain of custody is to protect the integrity of the sample throughout.  Laboratory personnel must therefore also adhere to and respect the procedures of the chain while samples are in their charge. Unless the chain of custody is maintained, even though the most sophisticated analytical tools and state-of-the-art methods were employed in analyzing samples, the results will not be representative of the evidence as found at the crime scene and as such results cannot be reported with certainty. The smallest lack of professionalism might break the chain of custody and lead to the non-admission of the evidence into court or, in the worst case scenario, a contamination of the evidence and/or loss of the pertinent element/s.
Quality-assurance control
The forensic scientist must be fully aware of the quality control of his/her work. In this case quality is defined as the validity of the procedure used, and the way it was applied. There have recently been many new advances in technology and analysis methods. With such diversity now available to the forensic scientist, it follows that there is a greater chance of choosing the wrong or a less efficient technique than a few decades ago. The extraction procedures are a good example of the many different options available in the field of fire debris analysis. There are several techniques to choose from, e.g. passive headspace concentration, active headspace, solvent distillation, solvent extraction, solid phase micro extraction, etc., each of them presenting advantages and drawbacks. Additionally, multiple parameters can be changed for each of them (adsorbent and heating process, desorption process and solvent used, etc.). It is therefore important for the forensic scientist to ensure that valid procedures and methods are used as well as properly applied. This will strongly contribute to an improvement in the quality of work done by an arson laboratory.
Interpretation of the evidence.
After extraction, the sample is subjected to a GC-MS chromatographic analysis and examination of the resultant chromatogram using ion profiling methods. A forensic scientist not only has to perform analyses but also understand and interpret the results obtained. Analytical techniques are constantly evolving with superior sophistication offering improved limits of detection. The advantage; it’s now possible to analyze smaller more complicated samples than it was decades ago. The disadvantage; it’s more challenging to interpret the results.
For example; the use of GC-MS or even GC-MS/MS now supports the detection of very weak traces of gasoline, this was undetectable 10 or 20 years ago. A recent case of a house fire, suspected as arson, revealed traces of gasoline on floor samples. The presence of gasoline strongly supported the hypothesis of arson. Further analyses showed however that the gasoline contained lead and as such, it suggested the fuel had been there for a very long time and not related to the fire.
Another example is the now known interference of pyrolysis products released by burning substrates in the ignitable liquid residues (ILR) identification.
These two examples show how important it is for the forensic scientist to question him/her self about the worth of the results.
At UIS-AS we follow the ASTM E1618 procedure and additionally use GC-MS/MS in conjunction with GC-MS. Together with the information found in the GC-MS analysis, GC-MS/MS results is a second “confirmation” analysis and can clarify complex or trace responses seen in the GC/MS analysis. GC-MS/MS is a technique with ultra specificity which can eliminate pyrolysate interferences still prevalent in the GC-MS trace. The analysis of the fire debris using sophisticated techniques, enable us to provide an exact and irrefutable result, which can be presented as evidence in Court.

The Presence of Higher Order Reflections in WDXRF Spectra

Published Date

The fundamental principal of WDXRF (wavelength dispersive x-ray fluorescence) involves the radiation of a sample leading to the emission of fluorescent X-Ray radiation (from the sample) ofdiscrete wavelengths. The polychromatic secondary x-rays originating from the sample are diffracted by an analyzing crystal in all directions. By selecting the relevant Bragg angle each individual wavelength (spectral line of an element) is measured by the detection system. As each characteristic line of an element in the periodic table has a discrete wavelength, it therefore has a discrete Bragg angle and thus it is possible to determine the composition of the sample according to the Bragg angles.

Proficiency Testing

Published Date

As a SANAS accredited laboratory, adhering to a quality assurance system is imperative. In addition to stringent internal quality control checks, and the use of certified reference standards, the regular participation in proficiency testing schemes provides verification of the analytical competence of a laboratory.

Copyright © 2017 UIS Analytical Services. All Rights Reserved.
Joomla! is Free Software released under the GNU General Public License.
Joomla 1.6 Templates designed by Joomla Hosting Reviews