Kulim Kht Latex Surface Tension Test using Wilhelmy Plate

Kulim Kht Langmuir Blodgett Analyze nanoparticle monolayers

 KSV NIMA Langmuir-Blodgett systems:  
 Analyze nanoparticle monolayers at the air/water interface
‒ How do nanoparticles interact with each other or
 with other analytes such as proteins, lipids, etc…
 ‒ Do they assemble, aggregate, cluster, etc…
- Nanoparticle interactions with model lipid monolayers
‒ Drug delivery and encapsulation
 ‒ Nanotoxicology
‒ Enzyme activity
‒ Controlled and automated nanoparticle deposition on solid substrates
 • Form well-organized, mono- or multilayer films
‒ Enable formation of graphene layers on solid substrates
 • Graphene is an attractive material for its unique electron transport
 properties and for applications that require high layer integrity
‒ Metals and semiconductors
 • Metal nanoparticles, metal oxides, carbon nanotubes, quantum dots
‒ Interactions of deposited model lipid monolayers with nanoparticles
- The LB system is used for nanoparticle deposition to make solar panels.
- LB enables very controlled deposition of particles
 which improves the efficiency of solar panel energy production.
- In solar panels, many types are formed via a nanoparticle
 formation, aggregation, deposition process that has to be
carefully timed to prevent over-aggregation/clumping.
 LB enables precise control of deposition.

www.ksvnima.com

Kulim KHT Critical Micelle Concentration UMT

 Critical Micelle Concentration Experiments

 Theory of Critical Micelle Concentration Experiments

 Definition

Certain molecules can be classified according to their affinity towards polar and non-polar solutes. An affinity towards polar substances such as water is said to be hydrophilic, conversely an affinity towards non-polar substances such as hydrocarbons is said to be hydrophobic. A molecule may be either completely hydrophobic or hydrophilic, or it could have portions that are hydrophilic and portions that are hydrophobic. Such a molecule is said to be amphiphilic.

Amphiphilic molecules are very interesting, especially in the way they interact with water. The behavior can be considered to be similar to that of a magnet- the two ends of the molecule have opposite polarity and the water has the same polarity as one of the ends. The end with the same polarity as water is repelled away from the water (hydrophobic) and the end with the opposite polarity is attracted towards the water (hydrophilic). Two optional configurations exist, surfactants and micelles.  

This type of arrangement occurs at the boundary between any polar or non-polar liquid and air, if a non-polar liquid is used then the hydrophobic portion points downwards and the hydrophilic portion points upwards. The presence of these molecules at the surface disrupts the cohesive energy of the surface and thus lowers the surface tension. Such molecules are called surfactants, short for surface active molecules.

The other possible arrangement is with a cluster of molecules forming a ball within the liquid, known as a micelle. In the case of a polar liquid such as water the hydrophilic portions make up the exterior of the ball and the hydrophobic portions make up the interior.

In a non-polar liquid the arrangement would be such that the hydrophilic portions are pointed towards the center of the molecule and the hydrophobic portions are pointed away from the center. The formation of micelles is less favored than surfactants, which allows the investigation of amphiphiles through comparing surface tension with the concentration 

Kulim KHT Data Receiver Collection via PC

Kulim KHT Cortest HPHT Autoclave Inhibitor Testing

Traditional HPHT Autoclave designs have been enhanced by the introduction of real-time corrosion measurement instruments and probes, to accurately reproduce the multiphase flowing field conditions of operating pipelines and industrial environments.

Corrosion Measurement

- Early Practices

Shear Stress Measurement

- Effect of Velocity on Corrosion

- Laminar Flow Studies

Corrosion Modeling

- Multiphase Studies Accelerated

Pipeline Integrity

Automated Inhibitor Injection (A.I.I.)

- “Feedback” Chemical Pump Control

Key Words:     Corrosion monitoring, new, rapid technique, LPR, ER, field trial results, corrosion rate measurement, corrosion probe, high velocity, corrosion inhibitor, chemical inhibitor, high shear, flow loop, multiphase, jet impingement, rotating cylinder electrode, oilfield, pipeline, pipeline integrity, rotating cylinder autoclave, system’s design, wet gas

INTRODUCTION

This paper is intended to update the knowledgeable reader, as well as inform the uninitiated with a basic overview of modern corrosion testing laboratory equipment and field instrumentation. It is only intended as a starting point and is in no way to be construed as comprehensive.

Perusing Internet advertising is not a substitute for rigorous investigation of corrosion measurement equipment suppliers. Manufacturers must also be involved in day to day scientific corrosion studies, as well as R&D toward new products and faster results.

A catalog “bomb” may allow an end user results found similar to those in 1939, but today’s competitive global marketplace for produced finished products requires real-time corrosion monitoring and control, all the way from the geological formation up to and past the point of custody transfer.

Corrosion Measurement

For many decades’ production and pipeline operators used simple corrosion coupons as an intermittent corrosion weight loss measurement. NACE, ASTM and others made exhaustive attempts to upgrade the method, Conducting Corrosion Coupon Tests in Plant Equipment, ASTM G4-84 originating (A224-39) in 1939.

Additional test methods were developed by NACE and others, as example TM01-77-96, Laboratory Testing of Metals for Resistance to Sulfide Stress Corrosion Cracking in H2S Environments. The standard addressed “the testing of metals for resistance to cracking failure under combined action of tensile stress and corrosion in aqueous environments containing Hydrogen Sulfide (H₂S)”.

Shear Stress Measurement

The 1995 NACE Publication 5A195 State Of-The-Art on Controlled Flow Laboratory Corrosion Tests was a “compilation of experimental techniques intended to provide the most up to date information available at the time on evaluating the effect of velocity on corrosion”, called Shear Stress. Included in NACE #5A195 (but not limited to) were the contents:

-          Interpretation of Lab Measurements

-          Philosophy Behind Experimental Design

-          Experimental Systems

-          References

-          Appendix B Governing Equations:

-          Rotating Disk

-          Rotating Cylinder

-          Impingement Jet

-          Flow-Loop System

In 1996 NACE Publication #1D196 Laboratory Test Methods for Evaluating Oilfield Corrosion Inhibitors, coupled the above NACE #5A195 with the effects of chemical inhibitor applications under multiphase flow controlled test equipment for lab simulations.

During recent decades, ER/LPR became viable techniques adapted from lab studies and applied in the form of probes and instruments developed for long-term field studies.

Modern electronic components and high speed data acquisition evolution allowed a more rapid response corrosion rate measurement to be made in real time. Trade named MICROCOR*, the new probe/instrument system could be used to make measurements not only in electrolytic, but in non-conductive gas environments as well. The rapid response/Microcor Systems have been readily accepted by the corrosion community as touted in NACE Papers 1997 #288 A Critical Comparison of Corrosion Monitoring Techniques in Industrial Applications, and later in NACE 2000 #00090 Field Trial Results of a New Rapid Corrosion Monitoring System. 

Corrosion  Modeling

Multiphase Flow Regimes Simulation studies became more important around the 1960’s and evolved (1980s to 1990s) into modern laboratory test equipment assemblies. As example, Corrosion in Multiphase Systems Center (Ohio University) and Multiphase Interactive Systems & Technologies, Inc., Orlando, Florida, built full-scale loops and tilt-up sections were brought on-line around 1993. NACE 2000 Paper #00070 Corrosion Inhibition of Wet Gas Pipelines Under High Gas & Liquid Velocities is a good representative case study of the use of such systems as supported through consulting contracts, which were client sponsored by global operators and producers.

Recently several Universities and industry corrosion laboratories have built large scale Multiphase Flow Loops. As example, NACE 2002 Paper No. 02502 The Design & Development of a Large Scale, Multiphase Flow Loop for the Study of Corrosion in Sour Gas Environments and the 9^th Middle East Corrosion Conference proceeding’s papers, including Modeling the Effects of Multiphase Flow on Corrosion in Oil & Gas Production by Prof. P. Jepson, bring focus to the necessity of state-of-the-art laboratory testing equipment and components to make fast and reliable decisions and predictions about corrosion control in multiphase operations.

Pipeline Integrity

Another paper presented by CC Technologies titled “Engineering Challenge of Pipeline Integrity Management” emphasizes the importance of 1. Preserve Pipeline Infrastructure and 2. Pipeline Integrity Management Program. In the CCT summary is the key statement, “to maximize the cost benefit, pipeline integrity management programs must be established that optimize monitoring and inspection on specific pipeline conditions, which are integrated into risk models.”

An interesting reference work from CCT, sponsored by U.S. D.O.T./FHA should also be consulted, which can be easily accessed on the Internet at www.corrosioncost.com. The 733 page compendium, Corrosion Cost and Preventative Strategies in the United States presents a partial view of the global expense due to corrosion, as well as other associated expenses which are not direct corrosion costs, but instead management/measurement and remediation long term higher costs. 

NACE 2000 Paper #00068 Oilfield Corrosion Inhibitor Under Extremely High Shear Conditions by Nalco/Exxon Energy Chemicals emphasizes the importance of “high shear conditions, which must be carefully modeled in lab simulations using a new Jet Impingement test technique supported by a flow loop for accurate experimental control.

With the above developments came faster and easier development and evaluation of anti-corrosion inhibitor chemicals and drag reducing agents. Other lab test methods, such as Rotating Cylinder Electrode (RCE) as found in example NACE 2002 Papers #02286 Corrosion Inhibitor Film Life Studies Using RCE Flow-Through Test and #02497 Reproducibility in Rotating Cylinder Autoclave Testing of Corrosion Inhibitors also make important points about accurate modeling and simulation of field application operating conditions.

Automated Inhibitor Injection

Complimenting the high shear and impingement measurements, new Automated Inhibitor Injection (A.I.I.) systems are in operation since 1998 using the rapid response (Microcor) corrosion rate output signal to determine and control the optimum inhibitor chemical dose rate using variable flow rate inhibitor chemical injection pumps. 

CONCLUSION

Cost of corrosion and its associated long terms costs can be significantly reduced with properly configured laboratory HPHT simulation systems, in combination with the newest state-of-the-art A.I.I. skid installations. The initial cost of these systems is quite small compared to the potential savings in material assets, non-productive downtime, the global environment and personnel safety.

Kulim Kht TENSIOMETER CMC

What is critical micelle concentration (CMC)?

Generally speaking surfactants are molecules that contain two different parts: a hydrophilic head group and a hydrophobic tail. Each part of a surfactant has very different solubility properties. This causes the molecule to have limited solubility in any solvent and they tend to accumulate at the interface between two phases or form micelles. The most common examples of surfactants are soaps, which are usually sodium or potassium salts of organic fatty acids, such as oleic, palmitic or stearic acid.

Kulim Kht UM Seminar

“Q-Sense Copenhagen-concept Seminars 20th of March”

As mentioned in the last newsletter, we will continue with the Copenhagen Concept Seminars. Next one up is Q-Sense User Seminar Day at University of Malaya, Kuala Lumpur, Malaysia, together with our distribution partner Kulim Hi Tech on March 20. Gabriel Ohlsson, application scientist, will give lectures on QCM-D in terms of technology, applications and modeling. Dr. Che Hui Xin from Chemical Engineering USM, Nibong Tebal, will speak as invited lecturer about his research. Internal contact for more information: Gabriel Ohlsson.

Kulim Kht UM important to measure contact angles and surface tensions

This application note provides a brief introduction why it is important to measure contact angles and surface tensions of different surfaces and liquids. Additionally, a brief comparison to other surface characterization techniques is given. Finally, a list of application areas and industries where these properties are of importance with short example will be presented. More about what contact angle and surface tension are and how they can be measured can be found in the other application notes AN #101- AN #106.
Why measure contact angle and surface tension?
The large influence of surface chemistry has only recently been acknowledged in many industrial fields. In order to meet the challenges of the increased competition and the challenges of the feature in improving our quality of life and protecting our environment, the development of new surface-engineered materials and products are the focus of many fields of today´s scientific research. The precise characterization and knowledge of the properties of surface engineered materials and liquids are of utmost importance in the development of new, better performing products with improved qualities. The knowledge of the surface properties of raw materials and how to manipulate these properties of the material to fit a certain application has become a key role this process.  
Measurement of contact angles and surface tensions provides a better understanding of the interactions between solids and liquids or liquids/liquids. These interactions play a key role in understanding adhesion, material wettability, biocompatibility, lubricity of solid surfaces as well as the wetting, washability, spreading and adsorption of liquids. Contact angle and surface tension measurements provide the information needed for development and modification of liquids and solid surfaces using today´s sophisticated surface engineering techniques. Hence, almost any solid or liquid surface can be modified to fit an application.
How come contact angle and surface tension are so important ?
Molecules inside (bulk) a liquid/solid are in every direction affected by equal attraction forces, whereas the molecules at the surface lack a neighbor towards the air phase and therefore they have larger attraction forces towards the liquid/solid than air (see figure below). This leads to a situation where the interface has excess free energy. This excess free energy is characteristic for any liquid or solid. For liquids a spontaneous contraction of the surface will take place due to this free energy and the Surface Tension of a liquid is a direct measure of it. In the case of solids a contraction is hardly ever seen, but still this free energy is present at the interface of a solid. However, now it is called Surface Free Energy (instead of Surface Tension as for liquids) and can be accessed by measuring the contact angle of a series known liquids placed on the solid surface. The dimension of Surface Tension and Surface Free Energy is mN/m.
www.attension.com

Kulim Kht ACM Cyclic Voltammetry UTM

 Cyclic Voltammetry 

Cyclic sweeps are used to measure corrosion that proceeds at about the same rate all over the metals surface (uniform) and corrosion at discrete sites on the surface e.g. pitting crevice and stress corrosion cracking (localised). A typical experiment comprises of an electrochemical cell containing the electrolyte a reference electrode a platinum auxiliary and a working electrode of the metal under test. The instrument is connected RE to reference electrode AE to the platinum and WE1 to the working electrode. This applies to the Gill AC the Gill 8 and 12 the Field Machine and the manual potentiostat. A sweep is programmed into the sequencer say -1000 mV to +1000 mV @ 20 mV/min and the test started. The results can be interpreted in the Analysis package. To measure uniform corrosion the method of Tafel extrapolation is used the Tafel slope being the slope of the straight line portion of the semi-logarithmic polarisation curve. To determine the degree of localised corrosion the amount of hysteresis between the positive going sweep and the negative going sweep is calculated.

 At large perturbations away from Ecorr the reaction measured becomes almost totally oxidised (when going positive) or almost totally reduced (when going negative). The equations that describe the reactions at large overpotentials can be simplified to a linear relationship i.e. Anodic overpotential = ba.log(iapp/icorr) Cathodic overpotential = (-bc.log(iapp/icorr)). This allows an extrapolation of iapp from either the anodic or cathodic Tafel region to the open circuit potential and hence to obtain the corrosion current

Kulim Kht ACM AC Impedance/EIS UTM

AC Impedance
The Gill AC; Gill 8; Gill 12 and the Field Machine are all used for this test. A typical experiment sweeps from 10 kHz to 0.01 Hz with a 10 mV perturbation around the rest potential. The usual result is an nyquist impedance plot of half a semi-circle: the high frequency part giving the solution resistance and the width of the semi-circle giving the corrosion rate in the same manner as LPR. The analysis of this data is performed by circle fitting in the analysis software. One useful benefit of AC is the ability to measure the solution resistance at high frequency. This allows any instrument that incorporates AC to perform automatic IR compensation during DC tests.
At each frequency a sine wave is generated and fed into the potentiostat. This wave is then imposed on the cell and its potential and current flow measured. The measured values of current and voltage are compared for amplitude and phase and an impedance calculated. This is repeated for the rest of the frequencies and a plot generated. The standard starting point with AC impedance is the basic Randles circuit.

An alternate name for AC impedance is Electrochemical Impedance Spectroscopy (EIS). 

Kulim Kht Surface Free Energy

Determination of the surface energy of materials by using contact angle measurements 
What is surface free energy?

 Let's take a piece of a material and try to divide it into two parts. To accomplish this task, some energy needs to be spent in order to overcome interatomic forces holding the parts together. If the separation of the parts is carried out so gently that no deformation is induced in the bulk material, the energy spent can be associated with the excess energy of the two new interfaces formed. In theory, assuming that the above action can be reverted, the same amount of energy should be regained upon putting the two parts back together. In real systems, the splitting up a material into smaller parts always induces stresses and deformations in each of the parts formed, and therefore some energy is dissipated as heat and some is stored as elastic deformation. As a consequence, the accurate experimental determination of surface energy is only possible for isotropic liquids, in which bulk stresses quickly relax and the excess surface energy coincides with the surface tension. For solids, the true value of the surface energy cannot be measured. When applied to solids, the term "surface energy" acquires a totally different meaning and can be viewed as an "adhesive" parameter characterizing the affinity of the surface to other materials. The higher the surface energy of a solid, the more energy is gained upon bringing this surface into contact with other materials. Interfacial interactions play a key role in all multicomponent materials irrespectively of the number and type of their components or their actual structure. Recognition of the role of the main factors influencing interfacial adhesion and proper surface modification may lead to significant progress in many fields of research and development, as well as in related technologies [1].

Why measure surface free energy?  Ability to measure the surface energy of various materials is essential for ensuring compatibility between the given base material and the top coating one wishes to apply onto it or other materials one wishes to attach to it. The most straight-forward applications include matching a paint to a substrate or matching an adhesive formulation to the materials one expects to be glued together.  In many industrial applications, special tools are used for modifying the surface energy of various materials at will. Thus, to promote adhesion, the surface can be "activated" by plasma treatment or chemical etching, whereby its energy is increased, or on the contrary, it can be passivated by lubrication, silylation, or hydrogenation (see Figure 1). For instance, to ensure good adhesion of printing ink to polyethylene or plastic film, such as used in the production of packaging bags, the surface of the film is plasma-treated prior to printing. The same method can be used to enhance the adhesion of the polyethylene-polypropylene laminate applied to the surface of paperboard, which is an essential operation in the paperboard converting technology, or the adhesion and endurance of a teflon layer on the surface of kitchen items. Dewaxing a metallic surface is needed prior to lacquering to ensure good adhesion of lacquer to metal. Waxing a car does not only adds glance but also reduces the adhesion of dirt to the lacquer. And after teflon-based waxes have become available on the market, care needs to be taken that a paraffin-based wax not be applied over a teflon-based one, while doing it the other way around would work fine.

Kulim Kht Bionavis SPR Real-time analysis of DNA

Real-time analysis of DNA hybridization with SAMP-SPR yields high specificity, improved signal-to-noise ratio, and a significantly cleaner sensorgram.

Background Experimental
Surface plasmon resonance (SPR) is a well-established technique for the monitoring of biomolecular interactions. SPR has been frequently used for the real-time analysis of hybridization of DNA and RNA oligonucleotides. One challenge in this context is that SPR is a non-specific detection method, i.e. any substance that adsorbs onto the sensor surface is detected. For example, SPR analysis does not indicate which strands in a mixture of oligos hybridize with an immobilized DNA strand on the chip surface. This is in sharp contrast to the high specificity of fluorescence- based analysis, where only the labelled oligo is detected.

Multi-Parametric SPR (MP-SPR) is a novel method utilizing the same physical principles as SPR, where not only the SPR peak minimum shift, but also other parameters from the optical signal are measured as a function of time.

In this Application Note we demonstrate how real-time SAMP-SPR analysis of DNA hybridization with MP-SPR using oligos labelled with Episentec™ dyes results in a specificity comparable to that of fluorescence analysis. Also the sensitivity sensitivity improved and disturbing signals are reduced, resulting in a better signal to noise ratio.

Hybridization of both unlabelled (native) and Episentec dye-labelled 25-mer DNA oligonucleotides (Episentec, www.episentec.com) were performed. Firstly, biotin-BSA conju- gate was spontaneously adsorbed onto a clean gold sensor chip followed by binding of avidin. A 25-mer DNA oligo with a spacer coupled to a biotin entity was then bound to the avidin. Subse- quently, a number of samples containing either native DNA, or DNA labelled with Episentec dye B10, were injected and hybrid- ized. Denaturation was performed with 25 mM sodium hydroxide. All experiments were performed using BioNavis Multi-Parametric SPR Navi™ 200. Enhanced sensorgrams were calculated in accordance with methods implemented in the EpiGrammer™ software.
www.bionavis.co