Sandra Wassink
Cover Image

This weekend it’s the Easter Weekend! It’s the top selling season if you look at chocolate gifts. If you have a look in the supermarket now, you will find chocolate eggs, easter bunnies and bonbons in many variations. In our office we also have a large bowl filled with colourful chocolate eggs already, delicious!

And if we talk about various flavours of chocolate, that’s part were flow instruments come into the picture.

Chocolate confectionery industry

I would like to share my findings within the growing chocolate confectionery industry and the trends in using flavours. Who else can do this better than a woman you should think, as 75% of the women report that they indulge in chocolate, against 68% of the men.

Chocolate… a growing worldwide market of $100 billion once started with a simple choice between Milk, Dark or White chocolate. Nowadays the choice in variations is huge due to flavourings.

Chocolate as a seasonal gift is still very popular. Around the holidays we tend to buy more chocolate. The top selling season for chocolate is not Valentine’s Day, as you might think, but Easter. Besides treating yourself with chocolate, there is an emotional aspect. Chocolate can have a positive effect on your mood, especially with young adults. A popular reason for the increasing sales. The majority of the chocolate buyers are looking for options with mix-ins as opposed to the conventional unflavoured varieties.

Chocolate production

Flavour and textures

The global chocolate market has seen considerable innovation in flavour and texture. New product development continues to be imaginative, with more exploration of flavours and textures in addition to the traditional sweetness. However, the consumer base tends to be rather traditional as the most popular flavours still are Hazelnut, Caramel and Almond.

Older consumers tend to have a lower engagement with chocolate. The lack of interest reflects their desire to eat healthy. To regain this group of adult customers, companies have turned to tactics such as using alcohol flavours, organic ingredients, and premium positioning such as dark chocolate with Limoncello or chocolates filled with sweet liqueur.

Coriolis flow meter dosing block

Healthy lifestyle

It may come as a surprise, but a healthy lifestyle, which is one of the major trends worldwide, is also responsible for a substantial growth of the chocolate market and that’s not without reason. Chocolate, specifically dark chocolate with more than 85% cocoa, can offer beneficial health benefits. This results in labels mentioning:

  • Rich in fiber, iron, magnesium, copper, manganese and other minerals
  • Powerful source of antioxidants
  • Protective against cardiovascular disease

The growing awareness of the health benefits of dark chocolate is one of the reasons why consumption of chocolate is increasing. With the rising popularity of dark chocolate, the sales for other variations are also going up. People are seeking other ‘healthy’ variations, such as sugar-free, gluten-free, kosher or fair trade chocolate. Due to these ethical claims, the industry has seen an enormous growth in variations.

In order to enhance a healthy image for chocolate, functional ingredients such as fibers, proteins, micronutrients, quick energy (guarana extracts), green tea extract, or chia seeds are more and more often added to the chocolate.

Cocoa

The increasing demand for chocolate also has its downside. About 3 million tons of cocoa beans are consumed annually of which more than 70% are produced by four West African countries: Ivory Coast, Ghana, Nigeria and Cameroon. Cocoa is a delicate crop and trees planted a quarter century ago have hit their production peak and the land they grown on are not as fertile as it once was. A large rehabilitation of land and trees is necessary to prevent the loss of crop production. Also climate changes are taking their toll.

This results in high costs for raw materials and unstable economic conditions in cocoa-producing nations. To prevent a supply shortage, a number of well-known chocolate producing companies have decided to invest in rehabilitation of the land and trees to make sure that cocoa will be available in the future. This happens in a time that developing countries such as China, India, and Russia expect to increase their chocolate sales volume by 30%.

Mass Flow Meters in your production process

Due to the enormous growth of chocolate variations, using flavours and functional ingredients, mass flow meters and controllers find their way into the confectionery industry. Coriolis flow meters in combination with a pump are an ideal solution for dosing flavours and functional ingredients. Using the Coriolis instruments for additive dosing means less downtime between batches, traceability of ingredients, and higher product consistency and quality.

Watch our video about an additive dosing solution for the confectionery market.

Download our brochure (Ultra) low flow Coriolis competence for the confectionery industry.

Rob ten Haaft
Cover Image

If we want to live healthy lives, we need to know the nature and content of undesirable chemical elements in our environment. If a municipal council wants to clean up a piece of land to develop a new suburb, it needs to know whether heavy metals or toxic substances such as arsenic remain in the soil from the previous use of the land. Likewise, the managers of drinking water sources, surface water bodies and fishing areas need to know about the quality of their water, to determine whether it contains excessive levels of undesirable substances that will have to be removed. And in order for air quality to be considered good, the trace element content in the solid particles floating in the air must not be too high.

Outside of the environmental field, there are other places where it is helpful to be able to identify and quantify the elements that are present – such as establishing the concentration of metal in lubricating oil to determine how quickly an engine will wear out, or the concentration of fertilisers in agricultural soil to determine whether additional fertiliser is required. Flow meters and regulators also play a major role here. As an industry specialist in the analytical market, allow me to explain how it all works.

Inductively Coupled Plasma – Atomic Emission Spectrometry, ICP-AES

As you can see, there are many applications in which it is useful to know what chemical elements are present and in what quantities. ICP-AES is a good analytical technique for measuring the nature and concentration of elements in solids, liquids and gases. This acronym stands for Inductively Coupled Plasma – Atomic Emission Spectrometry. Due to its high accuracy – up to the ppb (parts per billion) range – ICP-AES is particularly well suited to analysing trace elements, i.e. very low concentrations. This technique is excellent for detecting metals (such as mercury) and metalloids (such as arsenic), and dozens of elements can be analysed simultaneously. But what is behind this technique – and how does the careful delivery of gases play a role?

Controlled supply of argon gas through a flow controller

The short version: The ICP-AES method of elemental analysis uses an inductively coupled plasma to produce excited atoms and ions of the elements in the sample to be measured, whose characteristic spectrum is measured using atomic emission spectrometry (AES) as they return to their ground state. The intensity of the lines in the spectrum is directly proportional to the concentration of the elements in the sample.

The ICP-AES equipment can only analyse samples in liquid form. That’s not really a problem for water, but things get a bit tricky with soil samples and other solid substances. To unlock the chemical elements, you have to dissolve the sample in a strong acid: aqua regia, a mixture of hydrochloric acid and nitric acid. A peristaltic pump sucks the sample liquid out of a storage vessel and transports it to the nebuliser, which turns the liquid into an aerosol form or mist. To accurately regulate the concentration of the mist – and to dilute it if necessary – a flow of argon gas is supplied to the nebuliser, with the assistance of a flow controller. The mist then enters the reactor chamber, where it collides with the plasma that is already in the chamber.

If you supply a gas with sufficient energy – by passing a high electrical voltage through the gas using a coil – then some of the gas atoms release electrons. In addition to the original gas particles, you now have a mixture of negative electrons and positively-charged ions. This ‘ionised gas mixture’ of charged particles is called a plasma; plasma is considered to be the fourth state in which matter can exist, in addition to the solid, liquid and gaseous states. With ICP, argon gas forms the basis for the plasma, and this gas must be supplied with great precision, using flow controllers. The plasma has a very high temperature of around 7000 degrees Celsius. Because the plasma must have the correct composition at all times, a precise and continuous flow of argon gas is important. And to protect the outside world from this high temperature, a cooling gas (often but not always argon) is channelled around the outside of the reactor.

Regulating the mist

When the mist with the chemical elements to be measured collides with the plasma, these elements are also converted into plasma. The elements absorb so much energy that they enter an excited state. Elements don’t like to be in an excited state, so they try to return to their ground state at a lower energy level. During this transition, the elements emit radiation that is characteristic of each element. This radiation is measured by a spectrometer, and the intensity of the measured radiation is directly proportional to the amount of the element in question in the sample. Since each element has its own characteristic set of wavelengths of the emitted radiation, you can use this technique to identify multiple elements at the same time. And if you have a calibration curve for the elements concerned, or if you entered an internal standard into the nebuliser earlier in the process, then you can also quantify these amounts.

Spectrometer, ICP-AES or ICP-OES

The spectrometer within the AES part is a combination of mirrors, prisms, bars, monochromators/polychromators and detectors, which guide and ultimately measure the emitted radiation. To prevent any disruption to this process – such as the absorption of radiation by gases containing oxygen – the area where these optical objects are located is continuously flushed with nitrogen. This gas flow does not have to be very precise, but it does have to be highly reproducible. The use of flow controllers is essential to ensure this reproducibility. Incidentally, you may come across the term ICP-OES (optical emission spectrometry), which is an alternate name for ICP-AES (atomic emission spectrometry). These are two different names for the same technology.

ICP-MS

Image description

ICP-MS is a similar technique for elemental analysis; the biggest difference is that the method of detection is not optical. The charged particles from the plasma enter a mass spectrometer (MS); here, they are separated on the basis of their mass-to-charge ratio, and the relative ratio of each of these charged particles is recorded. ICP-AES is performed at atmospheric pressure, but ICP-MS requires a vacuum. The detection limit for ICP-MS is lower than for ICP-AES.

In an environmental analysis, you can look not only at the total quantity of an element in a sample, but also at whether the element occurs in its free form or as a component of a chemical compound. By way of illustration: inorganic arsenic compounds are often more toxic than their counterparts in organic compounds. You can use ICP-AES and ICP-MS to distinguish between different forms of elements, a process known as ‘speciation’. However, this requires the different forms to be separated from each other before the ICP process, for example through ion exchange chromatography (IC). For this reason, the IC/ICP combination is very common.

Mass flow meters and flow controllers for ICP-AES

Image description

When ICP was first invented, the gases were added manually. When ICP became automated gas regulation was automated too, and mass flow meters were introduced. Mass flow meters and flow controllers are devices used in ICP-AES to supply inert gases. If you have good gas regulation, the entire system is more accurate and more stable, enabling lower detection limits. Which is helpful, given the increasingly strict quality and environmental standards.

Bronkhorst supplies flow meters for the analytical market; our customers include a number of large suppliers of analytical equipment. These customers are often supplied with specific ‘manifold’ solutions. In these solutions multiple functionalities are integrated into a single body, custom built for the customer. Compact instruments with small footprints are becoming more and more important in laboratories where space is increasingly restricted.

Read the application story “Controlled supply of gases in Inductively Coupled Plasma (ICP-AES) for environmental analysis”.

Dion Oudejans
Cover Image

Semiconductor chip technology is enhancing our lives in many ways. Emerged from semiconductor technology, MEMS chip technology is also present in devices around you in the form of sensors. Think of your smartphone that captures your voice and senses the smartphone position, orientation and movement by means of Micro Electro Mechanical Systems (MEMS). Adding those features is barely impacting the physical dimensions of a smartphone: it still fits in your hand and pocket.

This blog is about instrument miniaturization by MEMS chip technology and the benefits of miniaturized gas flow instruments for application in the field of gas chromatography. As a MEMS Product Manager at Bronkhorst High-Tech, I can see the benefits of miniaturization by MEMS technology in such applications.

Image description

IQ+ FLOW solution based on MEMS modules

Miniaturization by MEMS chip technology

Further miniaturization is achieved by combining MEMS modules in customer specific flow solutions.

Miniaturization

In a laboratory environment, it is advantageous to work with desktop-sized equipment. Advantages of increasing functionalities in table top equipment are: reduced space requirements, enhanced ease of operation and often reduced cost of ownership.

Gas chromatography equipment is a good example of a concentration of functionalities on a small footprint. Many types of gas composition and vapour composition can be analysed with high accuracy and for very low concentration levels. Additionally, there is a certain degree of automation involved. This is all within arm’s reach of a laboratory analyst.

Gas chromatography

The goal of gas chromatography analysis is to identify and measure the concentration of gas components in an analytical gas sample. Within the gas chromatograph (see picture 3), there is often a need for gas flow or pressure control. The picture shows a gas flow controller for the carrier gas stream (red) and a pressure controller for the split flow stream (yellow).

Image description

The principle of gas chromatography involves a controlled carrier gas stream that passes an injector, column and detector. A sample gas is injected for a short period of time, creating a gas sample plug. The gas sample plug is separated into gas components across the column, which become visible as peaks during detection.

Picture 4 shows an example of a gas chromatography output.

Image description

Headspace sampling

Let’s zoom in on dynamic headspace sampling that is used in combination with gas chromatographys. Headspace sampling refers to the gas space in a chromatography vial containing a liquid sample. The liquid sample is a solvent, containing material to be analysed. E.g. volatile organic compounds in environmental samples, alcohols in blood, residual solvents in pharmaceutical products, plastics, flavor compounds in beverages and food, coffee, fragrances in perfumes and cosmetics.

This is explained in picture 5. Dynamic headspace sampling is performed by purging the gas space and the adsorbent. The adsorbent collects the sample gas. After transport, the adsorbent is purged again to release the sample gas into a gas chromatograph.

Image description

Where a gas flow controller comes into play is at purging the headspace with a constant Helium or Nitrogen flow for a pre-determined period of time at a specified temperature between 10 - 200 °C. The gas flow, containing the headspace sample gas, passes an adsorbent that collects the headspace sample gas.

The adsorbent is usually made of Tenax TA material. Now, the adsorbent is transported to the inlet of a gas chromatograph. While the adsorbent is heated between 20 - 350°C, a controlled Helium or Nitrogen gas flow passes the adsorbent to release the headspace sample gas into the inlet of the gas chromatograph. The gas chromatograph does its job to analyse the sample. Different signal peaks in time show the different components and their concentration.

IQ+FLOW gas flow meters and pressure controllers

For flow instruments, a number of specifications are important in headspace sampling and gas chromatography in general. The IQ+FLOW product line addresses these specifications with small instrument size, fast response, good repeatability, low power, low cost of ownership and the excellent support that you can expect from Bronkhorst.

Read more about the IQ+FLOW chip based product line

For more information about gas chromatography in combination with IQ+FLOW flow and pressure meters and controller have a look at our application note ‘Gas Chromatography'.

Image description

The future of MEMS technology

Bronkhorst is committed to look ahead and find applications that can be enhanced with MEMS chip technology. Feel free to contact us for questions. We will keep you informed!

Read more about MEMS technology in our blog 'Miniaturization to the extreme: micro-coriolis mass flow sensor'

Ferdinand Luimes
Cover Image

A Coriolis mass flow meter is known as a very accurate instrument and it has many benefits compared to other measuring devices. However, every measuring principle has its challenges, as also the Coriolis principle. It can be a real challenge using Coriolis instruments in low flow applications in the heavy industry where you may have to deal with all kinds of vibrations. In this blog I would like to share my experiences with you regarding this topic.

The Coriolis principle

Coriolis mass flow meters offer many benefits above other measuring devices. First of all Coriolis flow instruments measure direct mass flow. This is an important feature for the industry as it eliminates inaccuracies caused by the physical properties of the fluid. Besides this benefit, Coriolis instruments are very accurate, have a high repeatability, have no moving mechanical parts and have a high dynamic range, etc.

Read more about the importance of mass flow measurement and the relevance of Coriolis technology in a previous blog.

Do vibrations influence the measuring accuracy of a Coriolis mass flow meter?

In industrial applications, all kinds of vibrations with different amplitudes are very common. A Coriolis meter measures a mass flow using a vibrating sensor tube, which fluctuation gets intentionally out of phase when the fluid flows through. As explained in the video [link] at the end of this article.

This measurement technique is somewhat sensitive to unwanted vibrations with a frequency close to the resonance frequency of the sensor tube (this depends on the sensor tube design, e.g. 360 Hz) or a higher harmonic of this frequency (see picture below).

resonance

The likelihood of the occurrence of these unwanted vibrations is higher in an industrial environment. Coriolis flow meter manufacturers do their utmost to reduce the influence of vibrations on the measured value by use of common technical solutions, such as using:

  • higher driving frequencies
  • dual sensor tubes
  • different sensor shapes
  • mass intertia (e.g. mass blocks)
  • passive and active vibration compensation
  • pigtails

So yes, vibrations can influence the measuring accuracy of your Coriolis flow meter, but only if the vibrations have a frequency close to the resonance frequency. What can you do about this? This depends on the kind of vibration.

What kinds of vibrations do exist?

In an industry zone frequencies can be generated by:

  • environmentally related vibration sources (such as: truck, rail transportation, industry activities)
  • building-based vibration sources (mechanical and electrical installations, like air conditioning) or
  • usage-based vibration sources (installed equipment and machines, e.g. pumps, conveyor belts).

These vibrations travel through a medium like the floor, in the air, through pipes or the fluid itself. If these vibrations disturb the Coriolis frequency, the measured flow could be incorrect in some extent.

To minimise the effects of vibration it is useful to identify these sources. Sometimes, it is possible to move the flow meter just a little bit, turn it (Coriolis flow meters are in most cases less sensitive to vibrations if the meter is rotated 90 degrees), make use of a big(ger) mass block, use flexible tubes or U-bend metal tubes or use suspension alternatives.

How could you check the performance of a Coriolis flow meter?

A well performing flow meter and controller will give the best process result. Therefore, it is advisable to test a Coriolis flow meter in your application if you expect heavy industrial vibrations before you trust it to the full extent. Be careful when filtering the measuring signal. In some cases it makes sense (e.g. when a quick response isn’t required), but if you want to test the performance of a flow meter, filtering could blur your judgement.

Coriolis dosing block

If in specific circumstances the Coriolis flow meter isn’t performing the way it should, the operator will see a shift in the process output – for example in an application dosing colour to a detergent it can result in differences in product colour by incorrect dosing and/or unexpected measuring signal behaviour. In these cases it makes sense to check the raw measuring signal (without filters!), because it will give you a good insight in the performance of the flow meter. Ask your flow meter manufacturer how to switch off all signal filtering.

Standards regarding vibrations

Remarkably, the influence of external vibrations is not clearly defined in a standard for Coriolis flow meters. Several standards are written about vibrations, but none in respect to measuring accuracy in relation to vibrations. However, two useful standards in relation to vibration are:

  • IEC60068-2, Environmental testing for electronic equipment regarding safety
  • MIL STD 810, Environmental engineering considerations regarding shock, transport and use

As a user of Coriolis flow meters it is important to understand your application, especially about potential external vibration sources. As low flow Coriolis specialist we work together with knowledge partners like the University of Twente and TNO (a Dutch organization for applied scientific research) to get a continuous improved understanding of this topic.

With in-house test facilities we are able to do special vibration tests. Together with the experience we gained from customer applications and custom made solutions, we are always aiming for improving our Coriolis flow meters to give our customers the best performance they need.

Watch our video explaining the Coriolis principle

Learn more about the Coriolis measuring principle

Read more about the importance of mass flow measurement and the relevance of Coriolis technology in a previous blog.

Check out our success story using Coriolis mass flow controllers for odorisation of our natural gas.

Jos Abbing
Cover Image

Industrial low flow applications have to cope with a wide variety of environmental and process conditions, but what does this mean when we talk about ‘industrial’? Knowledge about the specific application and low flow fluidics will help a lot to prevent slipping.

We often refer to ‘uncontrolled macro-environments’ for equipment, when we talk about ‘outdoors’. However, it can also be a room or factory without (local) climate control in which equipment is experiencing comparable temperature and humidity variations as outdoors.

What is important in low flow applications and what kind of challenges do you encounter? Let me share my ideas in this blog.

What is IP-rating?

I experienced that IP-rating is not always interpreted correctly. Having the highest possible IP-rating is often mistaken with having an ‘industrial-device’. But what does the IP-rating actually indicate? The first digit of an IP-rating only refers to dust ingress protection and the second digit refers to the liquid ingress protection.

Therefore, a higher IP-rating does not always mean that the instrument is better and more suitable for your application. Hence, it can even make things much worse in practice. A reason for this is that even the tightest IP-rated constructions may breathe in and out, caused by internal and external temperature variations. This can lead to internal condensation, especially in high humidity environments, if no further precautions are taken.

The importance of dedicated low flow equipment

Not surprisingly, things are often a lot smaller in low flow applications. The other side of this coin is that common process and environmental disturbances have a proportional larger impact on these low flow applications compared to traditional ‘normal’-flow applications.

In general, an industrial flow instrument, like a flow meter, needs to be suitable to a lot of external influences, such as resistance to corrosion and impact or pressure ratings. These requirements often lead to selecting more standard industrial flow meters instead of specialised low flow instruments. This is not always the best solution for the required low flow ranges and can lead to unsatisfactory results.

Image description

What we want to achieve is to have rigid flow measurement and control, suitable for the application during the economic lifetime of the installation. Therefore, it would be best to select the best flow instrument fit for purpose. In case of low flow applications I therefore recommend to use dedicated low flow equipment. These flow meters are designed and tested for these kinds of applications. Our industrial low flow mass flow meters and controllers can be equipped with integrated control valves or dedicated pumps, especially designed for low flow purpose. Stable control characteristics are combined with signal-to-noise ratio plus being proportionally less sensitive for disturbances. Bronkhorst industrial low flow instruments We gladly support you in process and environmental equipment selections including system design aspects, starting with selecting the most suitable measuring and control principles. Our flow meter product portfolio contains laboratory-style and light-industrial flow meters to heavy-duty IEC-Ex/ATEX-rated industrial versions (…having a “high” IP-rating as well).

Image description

Drive your low flow control reliable and safely!

Our product manager for liquid technologies, Ferdinand Luimes, explains how to deal with vibrations using Coriolis mass flow meters

Visit us at the Hannover Messe (April 1-5, Hall 11, booth A50)) and have a sneak preview at our new industrial Coriolis flow meter.

Dr. Roland Snijder (HMC)
Cover Image

This week we have a guest blog from Dr. Roland Snijder, Medical Physicist Resident at Haaglanden Medisch Centrum (NL). To obtain his PhD degree at the Utrecht University, Roland worked as a researcher on the multi-infusion project at the department of Medical Technology & Clinical Physics of University Medical Center Utrecht (UMC Utrecht). His research focused on investigating physical causes of dosing errors in multi-infusion systems. In this research flow characteristics of multi-infusion setups were investigated using Bronkhorst Coriolis flow meters. In this blog Roland explains more about his research.

What is infusion?

Most patients admitted to the hospital are treated with medication (pharmaceuticals). Especially in critical care, a substantial amount of patients require intravenous therapy. Intravenous therapy means that a solution of pharmaceuticals are administered directly into the veins. The process of administering pharmaceuticals directly into the veins is called infusion and is done using a vascular access device (e.g. a catheter), which is inserted into the vein.

The importance of an accurate flow

Often patients in critical care, most notably young and premature patients, suffer from conditions that require the intravenous administration of very potent and short acting pharmaceuticals. These pharmaceuticals typically require a very accurate administration where deviations in flow- and thus dosing-rate can easily result in dosing errors. For this reason, infusion or syringe pumps are used.

On top of this, vascular access to the patient is typically limited and therefore many infusion pumps have to co-administer through one catheter (multi-infusion), making the entire pharmaceutical delivery process complex and hard to predict. Because dosing errors are common in clinical practice, it was clear that more research was required. Many of the results of this research can be found in the PhD-thesis: “Physical Causes of Dosing Errors in Patients Receiving Multi-Infusion Therapy”.

multi-infusion setup in clinical practice Fig 1. Example of a multi-infusion setup in clinical practice.

Flow measurement with Coriolis flow meter

We conducted a large amount of measurements to learn more about the flow characteristics of multi-infusion setups. These measurements were conducted using Bronkhorst Coriolis flow meters (series mini CORI-FLOW. These flow meters allowed us to measure the flow rate of infusion pumps very accurately, precisely and independent of the density of the solution being measured (although most of the solutions were similar to water).

The flow meters were also chosen because of the suitability for very low flow rates, infusion flow rates may be as low as 0.1 ml/h. Ultimately it is, of course, the dose rate or mass flow rate of the pharmaceutical administered to the patient that is important.

To measure this we used an absorption spectrophotometric setup, which enabled us to measure the concentration of a substance in a solution, i.e. a pharmaceutical or pharmaceutical-analogue. To convert density (e.g. µg/l) to a mass flow rate (e.g. µg/h), the cumulative flow rate (e.g. ml/h) of the infusion setup has to be measured as well.

mini CORI-FLOW mass flow meter

First we used a precision balance for this but later in the research project we used the mini CORI-FLOW flow meter. The data from the precision balance was rather noisy, whereas the flow meter provided very clean data, which improved our measurements substantially.

However, one point of caution that has to considered is that flow meters do produce a pressure drop resulting in intrinsic flow resistance. The implications of this and how the measurement setup relates to a clinical situation is thoroughly explained in the PhD-thesis.

The research concluded that a wide variety of infusion components all had a particular, usually significant influence and, importantly, medical personnel is usually not aware of the implications this has for infusion therapy. Awareness of the underlying mechanisms of these effects through education and technical innovation were recommended. The Coriolis flow meters from Bronkhorst proved to be very suitable for gaining insight in the different mechanisms of infusion pump system failure.

Further reading: R.A. Snijder - Physical causes of dosing errors in patients receiving multi-infusion therapy (ISBN: 978-94-028-0382-2)

About the author:

Dr. R. A. (Roland) Snijder (1985) is Medical Physicist Resident at Haaglanden Medisch Centrum (NL). He obtained a master’s degree in Biomedical Engineering at the University of Groningen with a specialization curriculum in the area of medical physics (medical instrumentation and imaging). In his master thesis, conducted at the University Medical Center Groningen, he investigated the effects of using computed tomography (CT) for lung cancer screening. After finishing his master thesis in 2012, Roland went on to pursue a PhD degree at the department of Medical Technology and Clinical Physics of University Medical Center Utrecht (UMC Utrecht).

Dr. Roland Snijder Dr. Roland Snijder (HMC)

Want to learn more about calibration of infusion pumps? Read the blog of Marcel Katerberg, explaining the calibration techniques to improve infusion pump performance.