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10 Benefits of Real-Time Particle Size Analysis

If you’re looking for optimal performance in the particle size analysis process, then real-time or ‘on-line’ particle size analysis methods, such as laser diffraction, are the way to go. There are several applications for real-time particle size analysis, including sticky-wet concentrated slurries, liquid emulsions, and dry particulate streams. With the use of automated on-line analysis, the frequency of measurement increases significantly, enabling a reliable and efficient data stream to be delivered.

Benefits of real-time particle size analysis

There are several benefits that can occur as a result of utilising real-time particle size analysers, outline below.

1. Increased return of investment (ROI)

These online instruments have been shown to be extremely sturdy and capable of providing 24/7 operation with only a small amount of upkeep. You can achieve visible ROI within six to 12 months of operation, with both product quality and plant capacity enhanced by automatic real-time measurement.

2. Lower energy

While milling operations are generally quite energy-intensive, consumption has been shown to see an exponential increase as particle size becomes smaller. Quality control failure can occur as a result of under-milling, while over-grinding can result in too much energy being used. With real-time particle size analysis you will see minimal energy use to create products that meet specifications.

3. Real-time control

From metal powders to pharmaceuticals, particle size is a key performance parameter in a lot of particulate products. Real time particle size analysis, therefore, makes a lot of sense. The on-line systems are capable of measuring up to four particle size distributions per second.

4. Troubleshooting

By utilising continuous measurement, you’ll be able to see the outcome of every variable in real time, which makes troubleshooting a lot easier than viewing these variables with the disadvantage of occasional off-line analysis methods.

5. Increased efficiency

Using off-line analysis to examine process parameters and their effects can be time consuming. With real-time particle size analysis, you’ll be able to evaluate these situations in minutes instead of hours. Causal links become clear at a much quicker rate than normal.

6. More intelligent process development

Since the acquisition of knowledge is the main role of process development, real-time measurement has obvious advantages. Potential problems can be detected at an early stage, speeding up the knowledge gathering process.

7. Quicker product changeover

Since, during changeover, you’ll want to get to the set point as fast as the plant dynamics will allow, on-line systems are definitely the way forward. Waiting on lab results to ascertain whether or not it’s safe to switch to the in-spec collection silo is no longer necessary; instead, you’re fed this information in real time.

8. Immediate upset detection

In general, offline analysis is done on an hourly basis (at most). As a result, any upsets may not be detected for an hour at best and response to upsets may take even longer – enough time to spoil a batch. On-line analysis allows upsets to be detected immediately.

9. Higher sensitivity to quality

Real-time data is sensitive to changing conditions, allowing for tighter process control. Off-line data, on the other hand, is usually an average taken from composite samples, which lacks the sensitivity necessary to spot out-of-spec samples.

10. Reduced operator risk

Occupational health and safety problems can arise during the sample extraction process, especially when materials are highly toxic or volatile. The use of a real-time particle size analyser eliminates this risk.

Find the right product to get the benefits

ATA Scientific offers scientific instruments suited to many scientific endeavours, including real-time particle size analysers. Browse our range of particle science products today to find what you need.

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A Guide to Understanding Laser Diffraction Principles + Theory

Laser diffraction has emerged as one of the most important and effective techniques in the world of particle size analysis thanks to its fast, non-destructive properties, its suitability for a broad range of particle sizes, and its ability to be fully automated. As a technique that measures particle size distribution for both wet and dry dispersions, it offers many advantages, including a high level of precision, fast response, high potential for the repetition of results, and a wide measurable particle diameter range.

The Role of Laser Diffraction in Particle Analysis

Over the last twenty years, laser diffraction has, to a large extent, replaced traditional methods of particle size analysis, such as sieving and sedimentation (a previously common practice for granular material).

Recognised for its capacity to reproduce results and size range spanning five orders of magnitude, laser diffraction has emerged as the technique of choice throughout the pharmaceutical industry where examining particle size is crucial in determining the performance of a product or process.

One example of this is the efficacy of ‘semisolid’ drugs, that are often used in ointments, creams, gels or lotions. Semisolid drugs have some of the properties of solids and some of the properties of liquids, so understanding the size of the particles they contain is crucial in knowing how each particular product should be delivered to the human body.

The scope for automation means modern particle size analysis can often be a matter of loading the sample and hitting a button, which is an exciting prospect for pharmaceutical companies looking to scale their research.

How Does Laser Diffraction Work

Laser diffraction is grounded in the relationship between light and surfaces (in our case particles). When light and surfaces interact, it results in either solely or a mix of refraction, reflection, absorption or diffraction. The latter offers the greatest scope for accurate particle size analysis assuming the diffraction system contains the following:

  • A laser – This is necessary as a source of intense and coherent light that’s of a defined wavelength.
  • A sample presentation system – This ensures that the material being tested successfully travels through the laser beam as a stream of particles that have a known state of dispersion and can be reproduced.
  • Detectors – Specialised detectors (typically an array of photo-sensitive silicon diodes) are applied to measure the light pattern produced across a range of angles.

Laser diffraction is what is known as a ‘cloud’ or ‘ensemble’ technique meaning it offers a result for the entire sample, as opposed to providing information for individual particles. Ensemble techniques use a broadened beam of laser light which scatters the light on to a specialised lens to offer a greater collection. During a laser diffraction experiment, particles are illuminated in a collimated laser beam – producing a scattered pattern of light – allowing scientists to deduce particle size and shape.

As a general rule, the bigger particles will bring about a high intensity of scattering at low angles to the beam and the smaller particles, on the other hand, create a low-intensity signal at far wider angles. These angular scattering patterns are measured with various specially-designed detectors and particle size distribution is determined from the resulting data.

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Laser Diffraction Models

Laser diffraction relies on optical models to help scientists understand data produced. The Mie scattering theory and the Fraunhofer diffraction approximation are two key theories used to calculate the type of light intensity distribution patterns produced by particles of various sizes.

Fraunhofer Theory

In the late 1970s, when laser diffraction systems were first introduced, limited computing power made it difficult, and impractical, to rigorously apply Mie theory. The Fraunhofer approximation of the Mie theory was a much easier model to use and was therefore widely adopted at this stage. It provides a simpler approach by additionally assuming that:

  • The particle size must be relatively large. It is recommended that 10x the laser wavelength is the minimum for this approximation.
  • The particles being measured are opaque discs.
  • Light is scattered only at narrow angles.
  • Particles of all sizes scatter light with the same efficiency.
  • The refractive index difference between the particle and the surrounding medium is infinite.

Mie Scattering Theory

Mie theory uses the refractive index difference between the particle and the dispersing medium to predict the intensity of the scattered light. It also describes how the absorption characteristics of the particle affect the amount of light which is transmitted through the particle and either absorbed or refracted. This capability to account for the impact of light refraction within the particle is especially important for particles of less than 50µm in diameter and/or those that are transparent.

Mie theory is based on the following assumptions:

  • The particles being measured are spherical.
  • The suspension is diluted, so that light is scattered by one particle and detected before it interacts with other particles.
  • The optical properties of the particles and the medium surrounding them are known.
  • The particles are homogeneous.

Choosing the Right Scientific Solution

Advances in computing power allow modern laser diffraction-based particle analysers to fully exploit the description of light scattering developed by Mie 100 years ago. The examples included here demonstrate how the ability of Mie theory to correctly predict the effect of particle transparency and changes in scattering efficiency make it superior to the Fraunhofer approximation, particularly for particles less than 50µm in diameter. ISO13320 recognises these benefits, concluding that the Mie theory provides an appropriate optical model across the full laser diffraction measurement range.

Modern measurement systems enable easier access to the powerful capabilities of the Mie theory through the inclusion of, for example, a database of refractive indices. These systems provide the greatest accuracy for the widest possible range of materials.

The Mastersizer range of laser diffraction particle size analysers set the standard for delivering rapid, accurate particle size distributions for both wet and dry dispersions.

Find Your Particle Size Analysis Solution

The team at ATA Scientific are experienced leaders in the scientific instruments industry, specialising in particle size analysis. Contact a member of the ATA Scientific team to find the right solution for your needs today.

7 Reasons Particle Size Analysis is Essential

An examination of the various industries that use particle size analysis during the manufacturing or production stage reveals that the process is used for a similar reason: quite simply, to control the amount of chemical reactions that occur when the product is being used. In this article, we’ll take a look at seven of the most crucial properties that are affected by particle size in various manufacturing scenarios.

1. Rate of reactions

When it comes to solids, the surface area of the particle is critical in determining the rate of chemical reaction. Chemical reactions are far more likely to occur in fine particles than otherwise. A great example of an industry reliant on this principle is the cement industry, which must deliver the appropriate reaction rate in order to achieve the desired product.

2. Potential to dissolve

The effect of particle size on dissolution rate is similar to the influence of particle size on the reaction rate. By creating finer particles and therefore increasing surface area, the physical barriers to dissolution are weakened, making the process occur much more quickly. Put simply, finer particles are more likely to dissolve quicker. The pharmaceutical industry knows the importance of this, as the speed of dissolution has direct effects on bioavailability and, therefore, the effectiveness of any given drug.

3. Packing density

The efficiency with which particles pack together is crucial to many industries as well. As a rule, large particles are going to pack more poorly than small particles. By decreasing the particle size, packing density is improved and voidage (unoccupied volume) is reduced. This is particularly important in production of metals through mould filling, as unoccupied volume can create a significantly flawed product.

4. Sedimentation

Suspension “stability” is most easily achieved buy avoidance of sedimentation (ie. the tendency of particles in suspension to settle out of the fluid). In order to ensure stability, the gravitational pull exerted on particles must be balanced with the “up-thrust” of the fluid. Unstable suspensions can wreak havoc in the food industry, for example, where consistency is essential to product perception.

5. Effectiveness of drug delivery by inhalation

In order to maintain the integrity of air supply in the body, our respiratory systems are incredibly efficient at filtering out particles above a certain size. This stops these particles from entering and damaging the lungs. Orally or nasally inhaled drug manufacturers must ensure the product is capable of penetrating the lungs; conversely, cleaning product manufacturers may need to provide extra controls in order to prevent inhalation if particles are of a dangerous size.

6. Product appearance

The principle behind the particle size analysis technique of laser diffraction is that particles will scatter light in different ways depending on their size. In some industries, however, this principle is important not just for analysis but also for end product — paint manufacturers, for example, must achieve desirable light scattering effects in order to define parameters such as hue, tint, transparency, gloss and so forth.

7. Texture

Overall, the size of particles can have direct correlation with a customer’s perception of a product and, therefore, the reputation of a manufacturing company. This is particularly true in the case of food products in which particle size can impact the enjoyment of the product; take coffee, for example, with which particle size affects the flavours released in the brewing process.

Particle size analysis instruments

There are a range of instruments available that will help you to undertake particle size analysis, many of which ATA Scientific have in their product range. Contact ATA Scientific today to for a free consultation.

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10 Applications for Particle Size Analysis

10 Applications for Particle Size Analysis

Particle size analysis involves using methods such as laser diffraction to measure the size of particles within a sample. By measuring and controlling particle size, manufacturers are able to deliver higher quality products. Here we look at 10 industries or products that have benefited from the application of particle size analysis.

1. Asthma puffers

For asthma sufferers, inhalers can help relieve respiratory discomfort on a day-to-day basis, and may even be the difference between life and death.

Studies have shown that asthma sufferers don’t always use their puffers according to directions, and the effectiveness of an inhaler can vary between users. In fact there are several factors that determine the efficacy of a puffer, including;

  • Construction of the device
  • Particle size of the drug
  • Technique of the user
  • Respiratory flow of the user

It is near impossible to ensure that asthma sufferers always chose the right puffer or consistently use the correct technique. Particle size, however, is one factor that manufacturers can control to ensure that asthma medication is delivered as efficiently as possible. Particle size analysis plays a key role in developing aerosols for effective delivery into the asthma sufferer’s lungs.

2. Inks

From pens, to computer printers, to professional book and screen printing – ink applications are wide ranging. Ink is essentially a fluid used to mark solids and there is low tolerance for error when it comes to the manufacturing quality of ink.

Particle size in pen ink relates largely to pigments which can affect:

  • Viscosity of the ink
  • Colour
  • Stability of the ink

Through careful analysis, manufacturers can gain control over the performance of fundamental ink properties, resulting in a better overall product and manufacturing process.

3. Cement

In cement manufacturing, there are two key areas where laser diffraction particle size analysis can have a material impact:

  • Controlling manufacturing costs
  • Increasing performance

Prior to the wide availability of particle size analysis equipment, common methods included the use of sieve and air permeability tests. While these methods are still in use, laser diffraction through particle size analysis is faster, cheaper and easier to use and automate.

When particle size in cement manufacturing plays such an important role in both price and performance, it’s no wonder particle size analysis is so widely used in this industry.

4. Road safety

The effectiveness of reflective surfaces used in road safety measures is dependent on the particulate size and distribution of reflective material.

Glass beads are typically used as the reflective surface. The reduction of impurities and promotion of desirable particle distribution can aid manufacturers in the production of glass beads that:

  • Reflect over greater distances
  • Reflect more uniformly
  • Last longer

Given the importance of providing clearly visible and reflective markings on long stretches of road and highway, accurate testing using particle size analysis is vital to ensure consistency and improvement.

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5. Ceramics

Ceramics are most commonly produced from powders. The size and distribution of particles within these powders has significant effects on both the function and manufacturing of ceramic products. Depending on the function of the ceramic, particle size analysis can aid in:

  • Densification
  • Transport
  • Mechanical properties

A single gram of ceramic powder can have billions of particles, with a total surface area of several square meters. Particle size analysis allows an understanding of both particle distribution and percentage of impurities within the powder. Using laser diffraction, the appraisal process is much faster and easier to accomplish than with a manual sieve.

6. Semisolid pharmaceuticals

In general terms, semisolids possess properties of both liquids and solids. In pharmaceuticals, semisolids are used for specific applications or in situations where the delivery of the drug is critical for patients who can’t accept traditional delivery types.

Example of semisolid pharmaceuticals include:

  • Ointments
  • Gels
  • Lotions
  • Creams

Because medicine is critical to our health and wellbeing, there is little room for error. With the help of particle size analysis, pharmacists and manufacturers can gain more accuracy in drug design and quality control, benefiting both patients and companies.

7. Cosmetics

The beauty industry is heavily reliant on semisolid products such as powders and creams. Particle size is a key factor in the consistency of these materials and laser diffraction can benefit analysis and development of a variety of cosmetic products.

  • Generally, moisturisers are oil in water emulsions, the formulation of which requires knowledge of both the particle size distribution of the oil dispersal and the zeta potential, which is the charge on the surface of the droplets.
  • Lipstick colour is related to the use and selection of pigments. Particle size affects the colour and effect of the product. Larger particles, for example, create sparkle and other lustre effects, while small particles typically create a ‘silky’ finish.
  • The particle size and distribution of foundations and other facial powders can affect the stability of the product, as well as appearance and capacity to provide sun protection through the use of light scattering components like zinc oxide.

When it comes to the highly competitive cosmetics industry, most manufacturers strive for perfection. Particle size analysis is therefore an indispensable tool in research and development of cosmetic products.

8. Soils and sediments

From farming and agriculture to building, construction, conservation and mining – soil and sediment are critical materials in a range of high value industries.

Soil and sediment can be classified into categories, most commonly:

  • Sand
  • Silt
  • Clay

Each type exhibits different qualities and varying levels of stability, water retention, aeration and drainage. Across all industries that require knowledge of soil properties, laser diffraction particle analysis can offer insight into the distribution of particulate types and the potential risks and benefits of given soil samples.

9. Food and drink

Size and distribution of particles in food and drink products can affect the taste, texture, appearance and stability of the product.

For example, coffee beans need to be ground into fine particulates after roasting and before brewing. Optimal levels of particulate size will depend on the type of bean, desired flavour and method of brewing. For coffee roasters, control over particle size is therefore extremely important for consumer experience.

Chocolate is another product that can benefit from laser diffraction. ‘Mouth feel’, which describes the optimal creaminess of eating chocolate, is a key factor in delivering a superior consumer experience. As chocolate is primarily a combination of milk solids and cocoa powder, particle size analysis can help chocolate producers manipulate their production process to maximise customer satisfaction.

10. Plastics

Plastics and polymers invariably benefit from particle size analysis. Polystyrene, for example, has particle sizes ranging from 20 nanometers to 1000 microns.

In most plastic manufacturing processes, the starting material is a pellet or powder. These feeder materials must meet a number of criteria, including:

  • Melting point
  • Flexural strength
  • Compressive strength
  • Impact resistance
  • Chemical resistance
  • Density
  • Tensile strength
  • Chemical composition

Each of these criteria are greatly affected by the particle size distribution of the pellets or powder. Particle size analysis can also improve transport and packaging processes – pellets and powders are easier to ship than heated slurries.

The benefits of particle size analysis

By using laser diffraction to measure particle size, this technique allows analysis of particle behaviour and consistency in a range of products. Understanding particle size gives manufacturers the information and control needed to ensure delivery of high quality products across a variety of industries.

If you’re in an industry that relies on particle size analysis, you’ll benefit from investing in quality instruments to measure particle size. ATA Scientific offers a range of products perfect for this application, so browse our product range today.

Basic Principles of Particle Size Analysis

What is particle size analysis?

Particle size analysis is used to characterise the size distribution of particles in a given sample. Particle size analysis can be applied to solid materials, suspensions, emulsions and even aerosols. There are many different methods employed to measure particle size. Some particle sizing methods can be used for a wide range of samples, but some can only be used for specific applications. It is quite important to select the most suitable method for different samples as different methods can produce quite different results for the same material.

Who uses particle size analysis?

Particle size analysis is a very important test and is used for quality control in many different industries. In just about every industry where milling or grinding is used, particle size is a critical factor in determining the efficiency of manufacturing processes and performance of the final product. Some industries and product types where particle sizing is used includes:

  • Pharmaceuticals
  • Building materials
  • Paints and coatings
  • Food and beverages
  • Aerosols

Equivalent sphere theory

One basic problem in particle size analysis is characterizing particles using just one number. Most particle sizing techniques aim report particle size distributions on a two dimensional graph (ie. particle size on the x-axis and quantity of material on the y-axis). However, the difficulty with this is that there is only one shape that can be described by a single unique number, and that is the sphere. Only a sphere measures the same across every dimension. If we say we have a 100 micron sphere, this describes it exactly. We cannot say the same for a cube, where the 100 micron may describe the length of one edge, or even a diagonal transect.

For this reason, all particle sizing techniques measure a one dimensional property of a particle and relate this to the size of an “equivalent sphere”. One example is to measure the surface area of a particle and then report the size of sphere which has the same surface area. Probably the most common method is to measure the “volume” of each particle in a sample and report the size of a sphere which has the same volume as the particles being measured (this is what is done in Laser Diffraction methods).

Particle Sizing by laser diffraction

Laser diffraction has become one of the most commonly used particle sizing methods, especially for particles in the range of 0.5 to 1000 microns. It works on the principle that when a beam of light (a laser) is scattered by a group of particles, the angle of light scattering is inversely proportional to particle size (ie. the smaller the particle size, the larger the angle of light scattering). Laser diffraction has become very popular because it can be applied to many different sample types, including dry powders, suspensions, emulsions and even aerosols. It is also a very fast, reliable and reproducible technique and can measure over a very wide size range.

Other methods

There are many other methods for analysing particle size, other than laser diffraction. Sieving is one of the oldest particle sizing methods and is still widely used for relatively large particles (ie. > 1mm). When measuring very small particles (ie. < 0.5um), Dynamic Light Scattering is by far the easiest methods to use. And if you need to measure morphological properties of particles, (ie. shape as well as size), then image analysis methods are the only way to gain the extra information.

Contact ATA Scientific today for a free consultation.

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Factors Affecting Reaction Rate in Chemical Kinetics

Chemical kinetics or reaction kinetics is the study of rates of chemical processes. The study of chemical kinetics includes investigations on how different experimental conditions can influence the speed of chemical reactions and produce information about the reaction’s mechanism and transition states. It also includes the construction of mathematical models that can describe the characteristics of a chemical reaction.

Factors affecting reaction rate

Chemical kinetics deals with the experimental determination of reaction rates from which rate laws and rate constants are derived. In order for a reaction to occur, a collision must take place. This collision has to be of proper orientation and have sufficient energy to break the necessary bonds.

There are several factors that influence the rates of chemical reactions. For instance, the particle size distribution of a material, which can be deduced using a particle size analyser, will affect the reactivity of solids participating in chemical reactions. The following are other factors:

Nature of reactants

Reaction rate variation is dependant on which substances are reacting. Fast reactions include acid reactions, the formation of salts and ion exchange. Reactions tend to be slow when covalent bond formation takes place between the molecules and when large molecules are formed.

Physical state

The physical state, i.e. solid, liquid or gas, of a reactant is also an important factor of the rate of change. When reactants are in the same phase, thermal motion brings them into contact. If they are in different phases, the reaction is limited to the interface between reactants and reactions can only occur at their area of contact. Vigorous shaking and stirring may be needed to complete the reaction.

Concentration

According to the collision theory of chemical reactions, concentration is an important factor because molecules must collide in order to react with each other. When the concentration of the reactants increases, the frequency of the molecules colliding increases, striking each other more frequently. Increasing the amount of one of more reactants causes the collusions to happen more often, increasing the rate of reaction.

Temperature

Molecules at a higher temperature have more thermal energy and collision frequency is greater at higher temperatures.

Catalysts

Catalysts are substances used to facilitate reactions but remain chemically unchanged afterwards. The rate of reaction is increased when the catalyst provides a different reaction mechanism to occur with lower activation energy.

Pressure

When the pressure is increased in a gaseous reaction, the number of collisions between reactants will also rise, increasing the rate of reaction.

Instruments that can be used for studying reaction rate

Stopped-flow

A stopped-flow instrument is a mixing device that is most frequently used to study rapid kinetics. Small volumes of solution are rapidly driven from syringes into a high efficiency mixer to initiate a fast reaction. These reactions are usually recorded by spectroscopic techniques such as UV absorbance, fluorescence or circular dichroism. The most commonly used detection method is fluorescence spectroscopy because of its high sensitivity.

Stopped flow instruments can be equipped with up to four syringes, one for the sample and two or three syringes for double or sequential mixing of reagents.

Rapid kinetics fluorescence

This is another instrument designed specifically for the detection of rapid kinetics. Combined with the Bio-Logic stopped-flow quenched-flow equipment, it makes a very powerful kinetics analysis system, one with high sensitivity and very efficient data acquisition. The Spectrometer can be configured to measure reactions by UV absorbance plus fluorescence or two different fluorescence wavelengths.

Find the best instrument

ATA Scientific offers a range of products that can assist you with your scientific endeavours, large or small. For information and advice on which product will suit your specific needs, contact ATA Scientific today.

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Methods of Measuring Molecular Shape, Weight and Size

Who wants to measure molecules?

The answer is a surprisingly broad range of people and companies. Molecular weight and size is most often used in identification of proteins, and in characterisation of polymers.

Molecular Weight is commonly measured in industries such as::

  • Pharmaceutical industry
  • Biotech research
  • Medical analysis
  • The food industry
  • Petroleum and polymer industries

Measurement methods for molecules

Molecules are not simple shapes – unlike the fairly compliant, mathematically-uncomplicated atom, which is spherical, molecules are difficult to define as a simple shape. Hence, two measurements have become industry standards – the radius of gyration and the hydrodynamic radius – and analytical instruments are geared towards obtaining these.

Radius of gyration

Scientific instruments can be used to identify the centre of mass and dimensions of a molecule; this is its radius of gyration. It is measured directly using static light scattering; however this method has limitations at sizes lower than 10-15nm, and also for large molecules like polysaccharides. Viscometers are the tool which is most often used for determining radius of gyration, using the Flory-Fox equation.

Hydrodynamic radius

This is a behavioural property of a substance – a measurement of size based on how it moves, which means that it is much more useful in industrial or practical settings.

Size exclusion chromatography

Size exclusion chromatography is the method by which scientists determine the molecular size (not the weight!), of a particular substance.  Molecules are separated in columns packed with porous substances, which might include glass beads, polystyrene gels, silica gel, etc. Larger molecules elute more quickly through the columns, since the molecules cannot fit into as many spaces.    A concentration detector is placed at the bottom of the GPC columns to determine the amount of material of each size fraction. In traditional SEC/GPC systems, operators need to pass known standards through the columns before the sample.  By creating a calibration curve of size versus elution time, particle size of unknown samples can be calculated.

In more recent times, addition of other detection techniques such as Static Light Scattering and the Intrinsic Viscosity detector provide direct measurement of molecular weight and size so that traditional calibration techniques are not required.

Gel permeation chromatography

SEC is also commonly referred to by other names. When an aqueous solution is used to carry the sample through the column, the technique is often called “Gel Filtration Chromatography”, and the name “Gel Permeation Chromatography” is often used when solvents are used to carry the substance in question through the packed columns.

Get the right instrument

Using the right method to measure molecules is very important, just as using the right instrument for measuring molecules is essential too. ATA Scientific offers a range of scientific instruments, including the Malvern Omnisec – Advanced Multi-Detection SEC/GPC, that can assist you in undertaking your measurements, so contact us today to find the instrument you need.

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5 Fascinating Careers in Industrial Science

Careers in industrial science continue to expand with positions opening up in both government and private institutions, especially in the area of research and manufacturing. Graduates can choose from a range of careers in agricultural and biological sciences, the information and technology sector, food and pharmaceutical companies, as well as mining and mineral exploration.

With the unparalleled expansion of scientific knowledge, industrial scientists have the opportunity of working at the leading edge of scientific developments no matter whether they have a leaning towards biology, chemistry or physics.

There will be a career path in industrial science in a variety of fields, and this article looks at five fascinating careers to consider.

1. Industrial Microbiology

If you have a penchant to work in a multidisciplinary scientific environment, then industrial microbiology or biotechnology could interest you. Processes and production problems often take scientists in a variety of directions which means that an industrial microbiologist has to be adaptable across such fields as bioengineering, biochemistry and molecular biology. Career pathways can lead you into fields such as antibiotics and vaccines as well as many other healthcare products and even food and beverages which are produced by microbial activity, for instance, cheeses, yoghurts.

2. Environmental Engineering

Environmental engineering suits graduates who are concerned about the man-made environment and issues relating to water quality, waste disposal, air quality and dealing with contaminated land. Today, research into the prevention of pollution is supported by government and private agencies alike and graduates can expect to work with mechanisms of sustainability in either private companies or government research facilities.

3. Chemical Engineering

Chemical engineering provides a practical link between the theory of science and manufacturing. Industrial scientists with a preference for working in this area will be involved in designing of equipment and development of large chemical manufacturing processes in a variety of industries including photography and photographic equipment, manufacturing chemicals and health care products

4. Academic Research

Most academic careers in the area of industrial science will attract high achieving practitioners looking to develop their research and, naturally, to teach within universities. Professorial appointments are highly regarded and provide satisfying careers for experienced scientists. Although opportunities are limited, with the expansion in industrial scientific jobs as a whole, academic posts are becoming more frequently advertised.

5. Nanotechnology

Within the emerging realm of nanotechnology, jobs are being created across a diverse range of activities. From creating cosmetics and researching the nature of matter, to medical diagnostics and developing better batteries are just a few opportunities that provide blossoming careers for industrial scientists. It is safe to say there is a revolution in manufacturing and in production of new materials. The new ways in which these are made is largely under the direction of a highly qualified industrial scientist. You could find yourself working for a sports equipment company or the army. The choices are almost endless.

Industrial Science Growth

The outlook for employment in the area of industrial science is rapidly increasing. Government predictions of job growth show that this growth will continue for at least the next three years unabated. Even in times of slower employment growth, it is apparent that many companies will continue to research and develop new products requiring industrial science expertise.

Your future

Regardless of the field chosen, most people working in industrial science will gain first hand experience with cutting edge analytical measurement techniques. Measurement technologies such as Laser Diffraction, Dynamic Light Scattering, Spectroscopy, HPLC and Rheology are widely used in industrial science jobs. With the help of these cutting-edge technologies supplied by ATA Scientific, people around the world are expanding development of exciting new products that will shape our future world.

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Comparing SEM & TEM – Understanding the Pros and Cons

While Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) both encompass means of electron imagery, there are some key differences between the two. Firstly, the detailed, three-dimensional and topographical imaging, and the versatile information this provides, is a big reason why SEM is so effective. On the other hand, TEM uses energetic electrons to provide morphologic, compositional and crystallographic two-dimensional information on samples.

In this article, we look at SEM imagery and its wide array of uses, as compared to another means of imaging, TEM.

What is SEM Imagery

SEM scans a focused electron beam over a surface to create an image that can be used to obtain information about the surface topography and composition. It works to produce images by scanning the sample with a high energy beam of electrons. As the electrons interact with the sample, they then produce secondary electrons, backscattered electrons and characteristic X-rays.

What are the Benefits and Disadvantages of SEM

There are a range of benefits associated with using SEM. However, depending on the information required or the type of sample, there are some disadvantages to this method of imaging as well. Before deciding on SEM, the sample type and information required should be the top consideration.

Pros

The power of SEM cannot be underestimated. The process by which the focused beam of electrons creates a magnified image is so advanced that the magnification is anywhere between 10 and 1,000,000 times. As such, it is a key tool for basic research, as well as quality control and failure analysis.

The Phenom Pharos Desktop Scanning Electron Microscope is an affordable desktop SEM that uses a Field Emission Gun (FEG) source commonly only found in larger, more expensive SEM systems housed in Microscopy centers in major Universities. Designed for ease of use, the Phenom Pharos is superfast, enabling imaging in less than 30 seconds after sample loading, and it delivers crisp, high resolution imaging (<3nm) with elemental analysis.

SEM allows for the examination of samples such as metals, alloys and ceramics, as well as polymers and biological materials. It’s practical for sample imaging needed for forensic investigations, biological sciences, soil and rock sampling, and medical science.

In short, if the aim of sample imaging is to examine a relatively large area for surface details and composition, SEM is ideal.

Cons

Due to the nature of the technique and the way it processes samples, a disadvantage of SEM is the fact that it cannot image wet samples as they may be damaged by the vacuum required during operation.

An SEM is also limited when used to image non-conductive samples and colour images, or when used to take measurements involving height. Coating your sample (sputter coating) with an additional thin layer (~10 nm) of a conductive material, such as gold, silver, platinum or chromium, can help remove charging effects and produce better quality images. However, the drawback of sputter coating is it removes the atomic number-contrast and elemental composition analysis.

What is TEM Imagery

TEM is a very powerful tool for material science. A high energy beam of electrons is shone through a very thin sample where the interactions between the electrons and the atoms can be observed. Additionally, chemical analysis can also be performed. The high resolution allows for the analysis of quality, shape and size as well as density.

TEM uses electrons instead of light to reveal the finest details of internal structures, even down to individual atoms.

What are the Benefits and Disadvantages of TEM

TEM offers the most powerful magnification and as such has a wide range of applications that all help to provide information on both element and compound structure. However, despite the advantages of magnification and versatility, there are some disadvantages that need to be taken into account.

Pros

TEM offers powerful magnification with the potential of over one million times, or more. As such, this type of detailed imaging is useful for a variety of fields, from science, to education and industrial uses. The highly detailed images provide valuable insight into elemental and compound structure, lending to providing information on surface features, shape, size and structure.

In short, TEM offers valuable information on the inner structure of the sample, so it’s ideal for individuals looking to gain information pertaining to internal structure.

Cons

TEM is a very large and quite expensive piece of electron microscopy machinery. Due to the complexity of the item, special training is required not only to operate the product, but also to be able to accurately analyse the data that the sample imaging provides.

Moving aside from operating the product, there’s some laborious work involved in preparing a sample for analysis. Firstly, the nature of the sample needs to be taken into consideration. Specifically, will the sample be able to withstand the vacuum chamber? The sample needs to be sliced thin enough for electrons to pass through, but also be able to withstand the process of analysis.

Additionally, sample analysis is limited to materials that are electron transparent.

Let ATA Scientific Find Your Next SEM Solution

When it comes to choosing between SEM and TEM, one technique isn’t better than the other – it comes down to the analysis required. Looking for internal details of small samples, TEM is useful. Need to determine surface information, SEM is best. For more information regarding Scanning Electron Microscopes and Transmission Electron Microscopy contact us today at ATA Scientific.

Measuring Surface & Interfacial Tension

At a basic level, surface and interfacial tension have a lot of similarities. In their simplest form, they are both effects which are based on liquids. While we may observe these effects in everyday life in the shape of droplets or soap bubbles, interfacial tension and surface tension are two different phenomenons.

Surface tension is defined to a single liquid surface, whereas interfacial tension involves two liquids that don’t mix together. The differences don’t end there, though, as both surface and interfacial tension require different means to measure the tension appropriately and effectively.

What is Surface Tension

The phenomenon called surface tension is the property at the surface of a liquid that causes it to behave like a plastic sheet. Essentially, the cohesive forces between liquid molecules are responsible for what we know to be called surface tension. The molecules at the surface don’t have similar neighbouring atoms all around, so they cohere stronger to those directly associated with them on the surface.

How Surface Tension is Measured

A traditional measurement of surface tension is the du Noüy ring method.

However, surface tension can also be measured using the Wilhelmy plate method, which is a simple and accurate form of tensiometer. This type of measurement relies on the interaction between the platinum plate and the surface of the liquid.

In this method, the position of the probe relative to the surface is significant. As the surface comes into contact with the probe, the instrument will detect this by the change in force that it experiences. Subsequently, the height at which this occurs and zero depth of immersion is registered. The plate is then wetted to a set depth, and when it is returned to the zero depth of immersion the force is registered and used to calculate the surface tension.

Products like the Attension Theta Flex are used as an optical tensiometer to characterise surface properties.

What is Interfacial Tension

Interfacial tension can be described as the force that keeps the surface of one liquid from interfering with the surface of another liquid. It’s a measurement of the cohesive or excess energy present at an interface arising from an imbalance of forces. This happens when two different phases, like gas and liquid, come into contact with each other, resulting in the molecules at the interface experiencing a force imbalance.

This type of imbalance leads to a buildup of free energy at the interface. This excess energy is commonly referred to as surface free energy and can exist at any type of interface. However, if it exists at the interface of two immiscible liquids, the measurement is one of interfacial tension.

How Interfacial Tension is Measured

Interfacial measurements can be done through the optical tensiometer by pendant drop shape analysis. The shape of the drop hanging on the needle is determined by a balance of forces, which include the surface tension of the liquid. Then the interfacial tension can be related to the drop shape by the equation.

Interfacial tension can also be measured by a force tensiometer. This instrument measures the forces exerted on the probe which is positioned at the liquid/gas interface. The probe is connected to a sensitive balance and interested liquid interface is brought into contact with the probe. Subsequently, the force measured by the balance as the probe interacts with the surface of the liquid can be used to calculate the tension.

The Difference Between the Two

Both interfacial tension and surface tension are effects based on liquids. Additionally, both effects take place due to the unbalanced intermolecular forces between liquid or solutions molecules. However, while the location of the effects are the same, there are differences between the two.

Firstly, surface tension is defined as the force parallel to the surface, perpendicular to a unit length line drawn on the surface. Essentially, it relates to the property of the liquid in contact with gas phase. Comparatively, interfacial tension is defined only to immiscible liquids as it applies to the interface of the two liquids.

Due to the differences in where they occur, both surface tension and interfacial surface have means of measurement that suit each. Specifically, the Wilhelmy Plate is thought to work better with high surface tension liquids, whereas a rod or pendant drop method of measurement is more suitable for working out interfacial tension where the amount of liquid involved is limited.

Another difference is the vast impact of pressure and temperature on surface tension. Surface tension decreases almost quite linearly with temperature. Therefore, when the temperature increases, the molecular thermal activity increases causing the cohesive interaction to decrease. Pressure is another external factor that has an affect on surface tension.

How ATA Scientific Can Help You Determine Surface Tension

When determining surface tension, perhaps the best options are the du Noüy ring or Wilhelmy plate method, while optical or force tensiometres work best for interfacial tension measurements. For more information regarding surface and interfacial tension and measurement practices, contact us today at ATA Scientific.