Europium Dibenzoylmethide Triethylammonium Research Articles

Mechanical Characterization of EuD4TEA‐ and ZnS:Mn‐Enhanced Composites

AbstractTriboluminescent (TL) materials are assessed as components in structural health monitoring (SHM) systems within polymer composites. Processing must be addressed due to particle characteristics such as density, morphology, and chemical makeup, all of which can affect polymer curing dynamics and thermo‐mechanical properties. This study considers key processing parameters during incorporation of TL compounds into various polymers. The TL materials chosen for this study are zinc sulfide manganese (ZnS:Mn) and europium dibenzoylmethide triethylammonium (EuD4TEA). These crystals are dispersed within the liquid phase of polyvinyl ester (VE), polydimethylsiloxane (PDMS), and Dymax 9663 ultraviolet‐curable (UV‐curing) resins. Incorporation of the europium compound apparently slows the cure process, particularly in the UV‐curing resin, while the zinc compound had a minimal effect on curing. Tensile testing shows a decrease in tensile modulus due to incorporation of TL crystals. Incorporation of the europium compound caused a 20–53% decrease in modulus; incorporation of the zinc compound caused a 7–66% decrease in modulus. Experimental results are used to create a multi‐scale model using Digimat. Discrepancies in the found values may be due to sample quality (e.g. presence of voids in experimental samples).

Incorporating strongly triboluminescent europium dibenzoylmethide triethylammonium into simple polymers

As mankind continues to extend technological boundaries, sensors must be improved in order to keep pace. The current problem that engineers and scientists face is how to actively monitor structures for damage. One possible method is to embed a triboluminescent material into a composite structure. Nearby sensors would monitor these structures for structural failure or impacts. This paper reports on recently completed research that incorporated the strongly triboluminescent europium dibenzoylmethide triethylammonium (europium tetrakis) into a selection of polymers, such as poly(methyl methacrylate). Additional work was completed to determine if europium tetrakis could be mixed with Cytoseal 60 and 280 to form a durable triboluminescent polymer for small-area sensors. Using a custom-built drop tower, the triboluminescent light yield and decay times was measured for the newly created triboluminescent polymers. In this paper, we have studied the effects of increasing poly(methyl methacrylate) (PMMA) concentration on the triboluminescent properties of europium dibenzoylmethide triethylammonium (EuD4TEA). The research shows that the amount of PMMA could be increased such that the EuD4TEA PMMA polymer could be sensitive to selective minimum energies. Thus, a functional triboluminescent polymer was successfully obtained for the first time.

Effects Of Crystallite Grain Size On The Triboluminescent Emmision For EuD4TEA

One of the brightest tested triboluminescent materials is europium dibenzoylmethide triethylammonium (EuD4TEA). In 2011, the authors discovered that synthesizing EuD4TEA using europium nitrate instead of chloride significantly increased the triboluminescence yield. In 2012, the authors discovered that anhydrous ethanol is not the best solvent to be used for synthesizing EuD4TEA. The less expensive acetone increases the triboluminescence and makes the synthesis much easier. However, no study has ever been done on how increasing the crystal size of EuD4TEA changes its triboluminescence. This paper reports the effect of increasing crystal size on the triboluminescence of EuD4TEA. The results indicate that acetone can be used to successfully control the grain size of EuD4TEA and thus increase the amount of triboluminescence emitted. The normalized TL yield is seen to be directly proportional to the square of the average grain size. The fluorescence decay time remains unchanged with an average value of 534.5 ± 7.3 µs, with no change in the emission properties of EuD4TEA. Copyright © 2013 VBRI press.

Triboluminescent Properties of Dysprosium Doped Europium Dibenzoylmethide Triethylammonium

The ability of an object to emit light upon fracture is known as triboluminescence (TL). While no complete theory on TL exists, its applications are limitless. One such use of TL is for detecting damage on aircraft or Lunar habitats. In order to make these sensors more effective, the TL must be bright. Europium dibenzoylmethide triethylammonium (EuD4TEA) is one of the brightest known materials. In 2010, the authors began investigating the use of dopants to increase the TL even further. Thus far they have been successful in increasing the TL of EuD4TEA by nearly 200%. This paper explores the effects of doping EuD4TEA with dysprosium. In addition, the effects of this addition on the decay time and the emission spectra are also reported.

Luminescent properties of lanthanide dibenzoylmethide triethylammonium compounds

Triboluminescence (TL) is defined as the emission of cold light based on mechanical action. In 1999, Sage and Geddes used this property to design a sensor capable of discerning the location of impacts. By coating a structure with various triboluminescent materials, impacts to structures could be monitored with simple light detectors. However, the intensity of most materials is very low. Of the thousands of known triboluminescent materials, only a few can emit enough light to be seen in daylight. One of these materials is europium dibenzoylmethide triethylammonium (EuD4TEA). This material shows 206% of the TL yield compared to the more commonly known manganese-doped zinc sulfide. Due to the high TL yield of EuD4TEA, exploration of the lanthanide series compounds was attempted for different emission wavelengths. This will help to monitor the locations of impacts on structures. This paper will investigate the TL yields, TL decay times, and the spectra of various lanthanide dibenzoylmethide triethylammonium compounds.

Review of Triboluminescence Impact Research at Projectile Speeds of 1 m/s to 6 km/s

Over the last decade, research has been conducted to investigate the use of triboluminescence (TL) as the active element for impact sensors. TL is defined as the emission of light produced by mechanical action. For the last decade, the authors has obtained extensive experience in characterizing TL and has successfully measured it during impacts with speeds of 1 m/s to about 5.6km/s. For the most part, zinc sulfide and europium dibenzoylmethide triethylammonium (europium tetrakis) compounds have been used as sample materials, since both emit strong TL. Recent ballistic results also show there is a ~1nm shift in the triboluminescent peak wavelength between the high speed 30 caliber and low speed 9mm projectiles augmented with ZnS:Mn powder. In fact, the 9mm peak wavelength for triboluminescence is similar to what was found in earlier measurements. More significantly, collected results also show that the triboluminescent emission yield for ZnS:Mn appeared to be a function of speed for collisions up to 6km/s using a two-stage light gas gun. These research programs expanded the knowledge base for using TL as the active element for sensors to detect high-speed impacts.

Effects of added uranium on the triboluminescent properties of europium dibenzoylmethide triethylammonium

The ability of a material to emit light upon fracture is known as triboluminescence. One of the few materials that emits triboluminescence in daylight is europium dibenzoylmethide triethylammonium (EuD4TEA). It has been shown that this material is 106% brighter than ZnS:Mn when excited by low speed impacts. In 2011, the authors of this paper found that replacing the traditional europium chloride with europium nitrate and changing the carrier solvent could both significantly affect the triboluminescent emission yield. While these changes provided a significant increase in yield, the emission was still not sufficient to be observed in bright daylight. In order to enhance the effect, a series of materials were added to the EuD4TEA to study the effects of “doping” on the triboluminescence yield. Results from this research showed that doping from a small number of materials, such as uranyl acetate, increased emission yield. This paper discusses the research that was completed on effects of the addition of uranyl acetate to EuD4TEA could increase the triboluminmescent emission yield. Results show that the added uranium does indeed increase emission yield when it is first synthesized. However, radiation emitted by the uranium also was found to damage the doped EuD4TEA, thus reducing the emitted triboluminescence over a period of time.

Measuring the Process Variability in Triboluminescence Emission Yield for EuD4TEA

Europium dibenzoylmethide triethylammonium (EuD4TEA) is one of the brightest known triboluminescent materials. Emission from EuD4TEA can be seen in daylight and has been found to be more than twice as bright compared to inorganic ZnS compounds. Using a custom-built drop tower, the triboluminescent emission yield for five batches of EuD4TEA was measured. Results show that the measurement variance for the drop tower is less than 9 pct. In addition, no statistically significant batch-to-batch variations in the triboluminescent emission yield were observed for the synthesized EuD4TEA. It can be inferred that the measurement uncertainty for the triboluminescent emission yield between batches is, at most, on the order of a few percent.

Optimizing the Synthesis of Europium Dibenzoylmethide Triethylammonium

not Available.

Innovative triboluminescence study of multivitamin doped europium tetrakis

AbstractAs the Space Shuttle program ends, NASA is developing the next generation of space vehicles. These new concept designs will require new and innovative structural health monitoring capabilities. One way to solve this problem is with smart impact sensors that use triboluminescent materials. In 2011, the authors reported an 82% increase in the triboluminescence yield of europium dibenzoylmethide triethylammonium (EuD4TEA) by changing the starting material. It has been shown that introduction of dopants tends to enhance the triboluminescent light yield. Here we report the successful synthesis of a multivitamin doped europium tetrakis which appears to be spherical in shape. Inductively Coupled Plasma – Optical Emission Spectroscopy analysis showed the presence of 3.6% calcium, 0.62% magnesium, 0.1% iron, 0.01% copper and manganese. This new product has no shift in the triboluminescent or photoluminescent emission peaks, but only a change in the intensity. In addition, the doped EuD4TEA powder statistically emits more triboluminescence while having the same decay time. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Synthesis and characterization of highly triboluminescent doped europium tetrakis compounds

One of the most intriguing properties involving crystals is their ability to emit light when fractured. While this property was discovered over 200 years ago, no one has ever been able to come up with a complete theory that can predict the physical principles associated with triboluminescence. However, this has not stopped scientists from coming up with various uses for these materials. One such application is to use these materials as the active element for smart impact sensors that can warn of catastrophic impacts. If these sensors are to become a reality however, the material must emit a bright light when fractured. One of the brightest triboluminescent materials found thus far is europium dibenzoylmethide triethylammonium (EuD4TEA). This material was discovered by Hurt in 1966 and is bright enough to be seen in daylight. In 2011, the authors discovered that synthesizing EuD4TEA using europium nitrate instead of chloride significantly increased the triboluminescence yield and made the synthesis much easier and more consistent. However, to date, there are few investigations into the effects of dopants on the triboluminescence of EuD4TEA. This paper reports the investigation of the effects of various dopants on: (1) The triboluminescent light yield, (2) Crystal size and structure, (3) Synthesis time, and (4) Prompt decay time. Results show that inclusion of dopants during synthesis increases the triboluminescence emission of EuD4TEA by 55%, significantly reduces the synthesis time, and controls the decay time. All of these properties can be useful for constructing the first prototype of a customized impact sensor.

Comparison of the triboluminescent yield and decay time for europium dibenzoylmethide triethylammonium synthesized using different solvents

Europium dibenzoylmethide triethylammonium (EuD4TEA) is one of the brightest known triboluminescent (TL) materials. First synthesized in 1966, emission from EuD4TEA is bright enough to be seen in daylight. In this paper we report the synthesis of Eu(III) tetrakis compounds using different solvents, and their influence on the appearance, TL yield, and decay time. The physical appearance of Eu compounds changed with the solvent type. Further, the solvents influenced the time for nucleation and completion of the reaction. TL measurements show that Eu tetrakis compounds derived from acetone solvent had the largest emission, while the smallest emission with the shortest decay time was obtained for the product from chloroform solvent. Photoluminescent emission spectra for the compounds from different solvents show the 5D0 → 7F1, 5D0 → 7F2 and 5D0 → 7F3 peaks which are consistent with previously reported results for EuD4TEA. However the intensity of the 5D0 → 7F2 transition shows the 613.5 nm is larger than the 611.7 nm for the products from 1-butanol and methylene chloride. Eu compound from 1-butanol shows a more intense 616.5 nm and 624.2 nm peaks, of which the later peak is almost merged into the background for Eu compounds obtained from the other solvents.

Comparison of the triboluminescent properties for europium tetrakis and ZnS:Mn powders

In 2006, some authors determined that the triboluminescence (TL) of manganese-doped zinc sulfide (ZnS:Mn) increases with increasing impact velocity. In 2011, the authors discovered a method of synthesizing europium dibenzoylmethide triethylammonium (EuD4TEA) that produced TL 106% greater than ZnS:Mn. In fact, this material is bright enough to be seen in daylight. This paper investigates the effects of increasing impact energy on the TL of EuD4TEA and various grain sizes of ZnS:Mn using a drop tower. The low energy results indicate that increasing impact energy can increase the triboluminescent light yield for impact energies up to 1.4 J, the upper limit of the drop tower. The minimum activation energies required for each material are also explored. In addition, the effects of the increasing impact energy on the triboluminescent decay time are also investigated. The details of the experimental setup, synthesis of EuD4TEA, and results are discussed in this paper.

Triboluminescent materials for smart sensors

Since the beginning of 21st Century, scientists and engineers have been investigating triboluminescent materials for use in smart impact sensors. One of the brightest triboluminescent materials found thus far is europium dibenzoylmethide triethylammonium (EuD4TEA). This material was discovered by Hurt in 1966 and is bright enough to be seen in daylight. Through innovative design of the material synthesis steps and by exchanging europium chloride for europium nitrate, the triboluminescent emission was increased by over 80%. In addition, the material yield was increased, as chloride washing is not required. Here, we discuss the new synthesis process, triboluminescent results, and future applications of EuD4TEA phosphors.

Performance of high-speed ball bearings with jet-oil lubrication : R. J. Matt and R. J. Giannotti, Lubrication Eng., 22 (8) (1966) 316–326; 12 figs., 3 tables, 4 refs.

One of the most intriguing properties involving crystals is their ability to emit light when fractured. While this property was discovered over 200 years ago, no one has ever been able to come up with a complete theory that can predict the physical principles associated with triboluminescence. However, this has not stopped scientists from coming up with various uses for these materials. One such application is to use these materials as the active element for smart impact sensors that can warn of catastrophic impacts. If these sensors are to become a reality however, the material must emit a bright light when fractured. One of the brightest triboluminescent materials found thus far is europium dibenzoylmethide triethylammonium (EuD4TEA). This material was discovered by Hurt in 1966 and is bright enough to be seen in daylight. In 2011, the authors discovered that synthesizing EuD4TEA using europium nitrate instead of chloride significantly increased the triboluminescence yield and made the synthesis much easier and more consistent. However, to date, there are few investigations into the effects of dopants on the triboluminescence of EuD4TEA. This paper reports the investigation of the effects of various dopants on: (1) The triboluminescent light yield, (2) Crystal size and structure, (3) Synthesis time, and (4) Prompt decay time. Results show that inclusion of dopants during synthesis increases the triboluminescence emission of EuD4TEA by 55%, significantly reduces the synthesis time, and controls the decay time. All of these properties can be useful for constructing the first prototype of a customized impact sensor.

New lubricants for the heat-resistant alloys : R. W. Roberts and R. S. Owens, General Electric Rept. No. 66-C-22I, 1966, 26 pp., 7 figs., 9 tables, 10 refs.

The ability of a material to emit light upon fracture is known as triboluminescence. One of the few materials that emits triboluminescence in daylight is europium dibenzoylmethide triethylammonium (EuD4TEA). It has been shown that this material is 106% brighter than ZnS:Mn when excited by low speed impacts. In 2011, the authors of this paper found that replacing the traditional europium chloride with europium nitrate and changing the carrier solvent could both significantly affect the triboluminescent emission yield. While these changes provided a significant increase in yield, the emission was still not sufficient to be observed in bright daylight. In order to enhance the effect, a series of materials were added to the EuD4TEA to study the effects of “doping” on the triboluminescence yield. Results from this research showed that doping from a small number of materials, such as uranyl acetate, increased emission yield. This paper discusses the research that was completed on effects of the addition of uranyl acetate to EuD4TEA could increase the triboluminmescent emission yield. Results show that the added uranium does indeed increase emission yield when it is first synthesized. However, radiation emitted by the uranium also was found to damage the doped EuD4TEA, thus reducing the emitted triboluminescence over a period of time.