Name: experimental procedure for laboratory studies of in situ burning : flammability and burning efficiency of crude oil
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The authors would like to thank the Danish Council for Independent research for funding the project (Grant DDF - 1335-00282). COWIfonden funded the construction of the Crude Oil Flammability Apparatus and the gas analyzer, including the duct insert. Maersk Oil and Statoil provided the crude oils that were used for the representative results. None of the sponsors have been involved in the protocol or the results of this paper. The authors would also like to thank Ulises Rojas Alva for assistance with constructing the modified cone sample holder.

This protocol makes use of two different experimental setups that are used in steps 4-8, as shown in the accompanying schematics. The first setup is the Crude Oil Flammability Apparatus (COFA) (Figure 1 and Figure 4), which is a 1.0 &#215; 1.0 &#215; 0.50 m3 metal water basin designed to conduct small scale in situ burning of crude oil experiments, as shown for example in Van Gelderen, Brogaard, et al.22</su...

<ol>
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The two weathering methods discussed in this paper are a relatively simple approximation of the weathering processes that a spilled oil on water is subjected to17. Other, more sophisticated weathering methods can also be used to provide weathered crude oil samples, such as the circulating flume described by Brandvik and Faksness35. The advantage of the presented methods is that they require simple equipment and can be easily conducted in a laboratory environment. The result...

In situ burning of spilled crude oil on water is a marine oil spill response method that removes the spilled oil from the water surface by burning it and converting it to soot and gaseous combustion products. This response method was successfully applied during the Exxon Valdez1 and Deepwater Horizon2 oil spills and is regularly mentioned as a potential oil spill response method for the Arctic3,4,5,6. Two of the key parameters that determine whether in situ burning of oil will be successful as a spill response method are the flammability and the burning efficiency of the oil. The first parameter, flammability, describes how easily a fuel can be ignited and can lead to flame spreading over the fuel surface to result in a fully developed fire. The second parameter, burning efficiency, expresses the amount of the oil (in wt%) that is effectively removed from the water surface by the fire. It is thus relevant to understand the flammability and the expected burning efficiency of different crude oils under in situ burning conditions.
The ignition of oil slicks on water for in situ burning purposes is commonly addressed as a practical problem, with qualitative discussions on ignition systems5,7,8,9. The practical approach to the ignition of spilled oil as a binary problem, and labelling oils either &#34;ignitable&#34; or &#34;not ignitable&#34; (e.g. Brandvik, Fritt-Rasmussen, et al.10) is, however, incorrect from a fundamental point of view. In theory, any fuel can be ignited given an appropriate ignition source. It is therefore relevant to quantify the ignition requirements for a wide range of different crude oil types to better understand the properties of a crude oil that would label it as &#34;not ignitable&#34;. For this purpose, the developed method can be used to study the ignition delay time of an oil as a function of the incident heat flux, the critical heat flux of the oil and its thermal inertia, i.e. how difficult it is to heat up the oil.
In a previous study, we postulated that the main parameter that governs the burning efficiency is the heat feedback to the fuel surface11, which is a function of the pool diameter. The theory explains the apparent pool size dependency of the burning efficiency based on laboratory studies reporting low burning efficiencies (32-80%)8,12,13 and large scale studies (pool diameter &#8805;2 m) reporting high burning efficiencies (90-99%)14,15,16. The method discussed herein was designed to test the proposed theory. By subjecting small scale laboratory experiments to a constant external heat flux, the higher heat feedback for large scale pool fires can be simulated under controlled laboratory conditions. As such, the developed method allows studying the burning efficiency effectively as a function of the diameter by varying the external heat flux.
In addition to an external heat flux to simulate the larger scale of in situ burning operations, the experimental setups feature cooling of the oil slick by a cold-water flow, simulating the cooling effect of the sea current. The discussed method is furthermore compatible with both fresh and weathered crude oils. The weathering of crude oil describes the physical and chemical process that affect a crude oil once it is spilled on water, such as losses of its volatile components and mixing with water to form water-in-oil emulsions (e.g., AMAP17). Evaporation and emulsification are two of the main weathering processes that affect the flammability of crude oils18 and protocols for simulating these weathering processes are therefore included in the discussed method.
Herein, we present a novel laboratory method that determines the flammability and burning efficiency of crude oil under conditions that simulate in situ burning operations on sea. Previous studies on the flammability and burning efficiency of crude oils featured both comparable and different methods. The flammability of fresh and weathered crude oils as a function of an external heat flux was studied on water19 and under Arctic temperatures20. Burning efficiency studies typically focus on different types of fresh and weathered crude oils and environmental conditions at a fixed scale (e.g., Fritt-Rasmussen, et al.8 Bech, Sveum, et al.21). A recent study on the burning of crude oils contained by chemical herders is, to the knowledge of the authors, the first to study the burning efficiency for small, intermediate, and large scale experiments under similar conditions13. Large scale experiments are, however, not readily available for parametric studies due to the extensive amount of time and resources required for conducting such experiments. The main advantage of the presented method over the previously mentioned studies is that it allows for simultaneously studying both the flammability and burning efficiency of crude oil under semi-realistic conditions. The combination of studying these two parameters for crude oils as a function of both different oil types and the (simulated) pool diameter through easily repeatable experiments was previously unfeasible in practice.

<table border="0" cellpadding="0" cellspacing="0" width="943">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:208px;">DUC Crude Oil</td>
			<td style="width:139px;">Maersk</td>
			<td style="width:132px;">N/A</td>
			<td style="width:464px;">Light crude oil with r = 0.853 g/ml and h = 6.750 mPa*s.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:208px;">Grane Crude Oil</td>
			<td style="width:139px;">Statoil</td>
			<td style="width:132px;">N/A</td>
			<td style="width:464px;">Heavy crude oil with r = 0.925 g/ml and h = 133.6 mPa*s.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:208px;">SVM 3000 Stabinger Viscometer</td>
			<td style="width:139px;">Anton Paar</td>
			<td style="width:132px;">C18IP007EN-P</td>
			<td style="width:464px;">Viscosity and density meter for the fresh and weathered crude oils.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:208px;">Laboshake RO500</td>
			<td style="width:139px;">Gerhardt</td>
			<td style="width:132px;">11-0002</td>
			<td style="width:464px;">Rotary shaking table for emulsifying water and oil mixtures.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:208px;">Jebao Wave Maker RW-4</td>
			<td style="width:139px;">Jebao</td>
			<td style="width:132px;">N/A</td>
			<td style="width:464px;">Propeller (flow of 500-4000 L/h) used in the COFA setup to generate a current.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:208px;">Aquabee UP 3000</td>
			<td style="width:139px;">Aquabee</td>
			<td style="width:132px;">UP 3000</td>
			<td style="width:464px;">Aquarium pump for cooling of heat flux gauge.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:208px;">Adventurer Precision Electronic Balance</td>
			<td style="width:139px;">OHAUS</td>
			<td style="width:132px;">AX5205</td>
			<td style="width:464px;">Load scale used to weigh the oil for the COFA experiments and in the custom-made cone sample holder for the cone setup.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:208px;">3M Oil Sorbent Pads</td>
			<td style="width:139px;">VWR</td>
			<td>MMMAHP156</td>
			<td style="width:464px;">Hydrophobic absorption pads used to collect oil residues to determine the burning efficiency of the fire.</td>
		</tr>
		<tr height="66">
			<td height="66" style="height:66px;width:208px;">Mass Loss Calorimeter</td>
			<td style="width:139px;">Fire Testing Technology (FTT)</td>
			<td style="width:132px;">B11325-650-1-1608</td>
			<td style="width:464px;">A custom-made, circular holder was used for the testing of crude oil rather than the standard square sample holder. Includes a heat flux gauge with a range up to 100 kW/m2.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:208px;">34972A Data Acquisition / Data Logger Switch Unit</td>
			<td>RS Components Ltd.</td>
			<td style="width:132px;">702-7958</td>
			<td style="width:464px;">Produced by Keysight Technologies. Operated by Keysight benchLink data logger 3 software and equipped with a 20-channel multiplexer.</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:208px;">Keysight Technologies 34901A 20-channel multiplexer</td>
			<td>RS Components Ltd.</td>
			<td style="width:132px;">702-7939</td>
			<td style="width:464px;">Produced by Keysight Technologies.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;">Bellows-Sealed Valve</td>
			<td style="width:139px;">Swagelok</td>
			<td style="width:132px;">SS-1GS6MM</td>
			<td style="width:464px;">Toggle valve to open/close the water in- and outlet of the custom-made cone sample holder for the cone setup.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:208px;">Kronos 50 Peristaltic Pump</td>
			<td style="width:139px;">SEKO</td>
			<td style="width:132px;">KRFM0210M6000</td>
			<td style="width:464px;">Peristaltic pump used to cool the custom-made cone sample holder for the cone setup.</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:208px;">ARCTIC A28 Refrigerated Circulater</td>
			<td style="width:139px;">ThermoFisher Scientific</td>
			<td>152-5281</td>
			<td style="width:464px;">Water cooling reservoir used to cool the cooling water that flows through the custom-made cone sample holder for the cone setup. Includes a SC 100 Immersion Circulator controller.</td>
		</tr>
		<tr height="46">
			<td height="46" style="height:46px;width:208px;">Gas Analysis Instrumentation Console with Duct Insert</td>
			<td style="width:139px;">Fire Testing Technology (FTT)</td>
			<td style="width:132px;">B11328-650-1-1609</td>
			<td style="width:464px;">Gas analyzer for O2, CO2 and CO. Uses a 34972A Data Acquisition / Data Logger Switch Unit.</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:208px;">Ceramic &#38; Stainless Steel 2.5mm Electrode</td>
			<td style="width:139px;">Fire Testing Technology (FTT)</td>
			<td style="width:132px;">M015-4</td>
			<td style="width:464px;">Spark igniter from the Mass Loss Calorimeter. Used in the COFA setup to measure the surface temperature upon ignition.</td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:208px;">Infrared Emitter-Module M110/348</td>
			<td style="width:139px;">Heraeus</td>
			<td style="width:132px;">80046199</td>
			<td style="width:464px;">Original Infrared heaters on which the new design with a water-cooled holder for the heating elements was based. Includes two short wave twin tube emitters (09751751). Operated by a type CB1x25 P power controller.</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:208px;">Power Controller Heratron&#160;</td>
			<td style="width:139px;">Heraeus</td>
			<td style="width:132px;">80055836</td>
			<td style="width:464px;">Type CB1x25 P power controller for the infrared heaters.</td>
		</tr>
	</tbody>
</table>

experimental procedure for laboratory studies of in situ burning : flammability and burning efficiency of crude oil

A new method for the simultaneous study of the flammability and burning efficiency of fresh and weathered crude oil through two experimental laboratory setups is presented. The experiments are easily repeatable compared to operational scale experiments (pool diameter &#8805;2 m), while still featuring quite realistic in situ burning conditions of crude oil on water. Experimental conditions include a flowing water sub-layer that cools the oil slick and an external heat flux (up to 50 kW/m2) that simulates the higher heat feedback to the fuel surface in operational scale crude oil pool fires. These conditions enable a controlled laboratory study of the burning efficiency of crude oil pool fires that are equivalent to operational scale experiments. The method also provides quantitative data on the requirements for igniting crude oils in terms of the critical heat flux, ignition delay time as a function of the incident heat flux, the surface temperature upon ignition, and the thermal inertia. This type of data can be used to determine the required strength and duration of an ignition source to ignite a certain type of fresh or weathered crude oil. The main limitation of the method is that the cooling effect of the flowing water sub-layer on the burning crude oil as a function of the external heat flux has not been fully quantified. Experimental results clearly showed that the flowing water sub-layer does improve how representative this setup is of in situ burning conditions, but to what extent this representation is accurate is currently uncertain. The method nevertheless features the most realistic in situ burning laboratory conditions currently available for simultaneously studying the flammability and burning efficiency of crude oil on water.

Figure 5 shows the evaporation curve of a light crude oil that was evaporated over multiple days to a loss of 30 wt% using the method described in step 2. The figure clearly shows that after the first day (19 h) of evaporative weathering, the evaporation rate is reduced significantly, which allows for pauses as mentioned in the protocol.
Figure 6 shows the ignition dela...

Watch this Scientific Journal Video about Experimental Procedure for Laboratory Studies of In Situ Burning : Flammability and Burning Efficiency of Crude Oil at JoVE.com

Experimental Procedure for Laboratory Studies of In Situ Burning : Flammability and Burning Efficiency of Crude Oil

Here, we present a protocol to simultaneously study the flammability and burning efficiency of fresh and weathered crude oil under conditions that simulate in situ burning operations on the sea.

Experimental Procedure for Laboratory Studies of In Situ Burning : Flammability and Burning Efficiency of Crude Oil

A new method for the simultaneous study of the flammability and burning efficiency of fresh and weathered crude oil through two experimental laboratory ...

The overall goal of this experimental procedure is to quantify and improve the understanding of the ignition requirements and the resulting burning efficiency of crude oil spilled on water for oil spill response purposes. This protocol can help answer key questions for the in situ burning of crude oil spills, such as the strength and the exposure time needed for the ignition source. The main advantage of these laboratory experiments is that the flammability and the burning efficiency of crude oils can be studied simultaneously under conditions that represent operational-scale crude oil fires.Begin preparing oil samples for the experiments. Use this plastic container for the weathering process. It has holes drilled into its lid.There is also a hole in its side to accommodate a plastic tube connected to an O-ring with holes. Set up the container to bubble air through several liters of fresh crude oil. During the weathering process, monitor the oil's weight to know the weight percentage loss over time.Stop when the desired value is achieved, which can take several days. Emulsification of crude oil requires a rotary shaking table. First, vigorously shake 900 milliliters of the desired crude oil and water mixture for one to two minutes.Then place the bottle on the rotary shaking table to stir at room temperature. The Crude Oil Flammability Apparatus or COFA is under an exhaust hood. It is a metal water basin with an inlet and drain.For the test, prepare a glass cylinder. It should be five centimeters high and about 16 centimeters in diameter. Mount the cylinder on a stand and place the stand and cylinder in the center of the basin.Proceed by filling the basin with fresh water. Stop when the water is one centimeter below the edge of the glass cylinder. Mount a propeller on the basin wall to directly face the glass cylinder and adjust its height.Set its height and speed so the waves generated are barely observable in the water inside the cylinder. Turn off the propeller and prepare the oil. Pour the oil carefully on the water surface inside the glass cylinder.Next, slowly add water to the basin and stop when the surface of the oil slick is one to two millimeters below the edge of the cylinder. Start the propeller and prepare to time the burning. Use a butane hand torch to ignite the crude oil.Record the time from ignition until extinction. When the fire has extinguished, use hydrophobic absorption pads to collect the remaining oil. Shake any collected water off before weighing the pads to determine the burning efficiency.Have a different setup ready under a hood to study flammability. Use a cone heater equipped with shutters and a spark igniter. This heater also features a custom-made sample holder.This schematic highlights the features when the two are put together. The cone heater sits 23 millimeters above an oil slick which is in a metal holder. Valves regulate cooling water that flows below the oil.This schematic provides a sense of the elements beyond the heater and sample holder. There is a control unit for the cone temperature and the spark igniter. The complete water system is revealed, as is the presence of a gas analyzer that samples the exhaust gases.Start by heating the cone so there is a heat flux of three to 50 kilowatts per square meter at the oil surface. Also, cool the reservoir to a previously-determined temperature. When all is ready, connect the water tubes to the sample holder and get water flowing through the system.Shake the sample holder to remove trapped air. When the cone and sample holder temperatures stabilize, stop the pump. Close the valves on both sides of the sample holder, then disconnect the tubes.Take the sample holder to a load scale and tare the scale. Add oil at room temperature to the sample holder equivalent to a 10-millimeter slick thickness. When done, reconnect the sample holder, open the valves, and restart the water flow.After starting data acquisition, carefully place the sample holder under the cone. Prepare two stopwatches and move the spark igniter over the sample. Next, open the cone shutters and start the first stopwatch.When the oil ignites, stop the first stopwatch and start the second, then move the igniter into its neutral position. Wait for the fire to extinguish to stop the second stopwatch. Close the shutters and stop the data acquisition.Next, stop the water flow in the sample holder, close the valves, and disconnect the tubes. Place the sample holder on a tared scale and register its weight with burn residue. Clean the holder with a volatile, non-polar solvent.Weigh it again to determine the residue weight and thus the burning efficiency. Return to the COFA. Place a glass cylinder on a stand in the center of the apparatus.Next, put two water-cooled infrared heaters on adjustable footings into position on either side of the cylinder. Position them one to five centimeters from the cylinder's outer edge. Fill the Crude Oil Flammability Apparatus with water.The water level should be one centimeter below the edge of the glass cylinder. Place a propeller facing the cylinder at the previously-determined height. Now, prepare thermocouples for the cylinder.Mount three one-millimeter thick K-Type thermocouples on a frame, suspend this frame over the cylinder. Orient the frame so the thermocouples are along the radius, one to two millimeters below the cylinder edge. Slowly add water to the basin and check that the water touches each thermocouple at the same time as a test of their placement.To continue, drain the water so its level is again one centimeter below the edge of the cylinder. Ensure a spark igniter can easily move between a neutral position and the cylinder center. Start it in the neutral position.Pour crude oil equivalent to a five-millimeter thick slick onto the water inside the glass cylinder. Add water until the oil just comes into contact with the thermocouples. Move the spark igniter into position above the oil.Start data acquisition and a stopwatch simultaneously. Turn on the exhaust hood, the propeller, and the spark igniter. Turn on the infrared heaters at their predetermined power.Upon ignition of the oil, stop the stopwatch. Turn off the igniter and move it to its neutral position. Stop data acquisition and turn off the heaters and the propeller.Then, remove the thermocouples and extinguish the fire using a non-combustible cover. These data are for the ignition delay time as a function of the incident heat flux from the cone. There is data for fresh heavy crude oil and heavy crude oil that has undergone evaporation.The vertical asymptotes show the critical heat fluxes. This plot is of the heat release rate as a function of time for fresh light crude oil. It has a regular heat release rate profile.Compare this with data for an emulsified light crude oil which had a boilover at the end of the burn. Note the scales are different. Here is the burning efficiency as a function of the incident heat flux for two oil types, fresh light crude and evaporated heavy crude.The data were obtained with the cone setup. Data from the setup also allows a plot of the burning rate for the two oil types. This is an example of the surface temperature as a function of time from two thermocouples in the Crude Oil Flammability Apparatus.The spike indicates the moment of ignition. After watching this video, you should have a good understanding of how to study the flammability and burning efficiency of crude oils under conditions that simulate operational-scale crude oil fires on water. Once mastered, the various experimental procedures can be performed in 20 to 60 minutes per experiment if they are performed properly.While attempting this procedure, it's important to remember that, although the experimental setups are designed to simulate operational-scale conditions, the experiments are still conducted in a controlled laboratory environment and therefore the results should be interpreted accordingly. Following this procedure, other parameters that influence the problem such as wind and waves can be added to the experimental setups to further improve the representativeness of these experiments compared to real in situ burning operations. Don't forget that working with fire and crude oil can be extremely hazardous and precautions, such as personal protection items, a proper exhaust hood, and the safeguarding of combustible materials, should always be taken while performing this procedure.

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In-situ Tapering of Chalcogenide Fiber for Mid-infrared Supercontinuum Generation

Supercontinuum generation (SCG) in a tapered chalcogenide fiber is desirable for broadening mid-infrared (or mid-IR, roughly the 2-20 &mu;m wavelength range) frequency combs1, 2 for applications such as molecular fingerprinting, 3 trace gas detection, 4 laser-driven particle acceleration, 5 and x-ray production via high harmonic generation. 6 Achieving efficient SCG in a tapered optical fiber requires precise control of the group velocity dispersion (GVD) and the temporal properties of the optical pulses at the beginning of the fiber, 7 which depend strongly on the geometry of the taper. 8 Due to variations in the tapering setup and procedure for successive SCG experiments-such as fiber length, tapering environment temperature, or power coupled into the fiber, in-situ spectral monitoring of the SCG is necessary to optimize the output spectrum for a single experiment.
	In-situ fiber tapering for SCG consists of coupling the pump source through the fiber to be tapered to a spectral measurement device. The fiber is then tapered while the spectral measurement signal is observed in real-time. When the signal reaches its peak, the tapering is stopped. The in-situ tapering procedure allows for generation of a stable, octave-spanning, mid-IR frequency comb from the sub harmonic of a commercially available near-IR frequency comb. 9 This method lowers cost due to the reduction in time and materials required to fabricate an optimal taper with a waist length of only 2 mm.
	The in-situ tapering technique can be extended to optimizing microstructured optical fiber (MOF) for SCG10 or tuning of the passband of MOFs, 11 optimizing tapered fiber pairs for fused fiber couplers12 and wavelength division multiplexers (WDMs), 13 or modifying dispersion compensation for compression or stretching of optical pulses.14-16

In-situ Tapering of Chalcogenide Fiber for Mid-infrared Supercontinuum Generation

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Supercontinuum  generation (SCG) in a tapered chalcogenide fiber is desirable for broadening mid-infrared  (or mid-IR, roughly the 2-20 &mu;m wavelength ...

Laboratory Drop Towers for the Experimental Simulation of Dust-aggregate Collisions in the Early Solar System

For the purpose of investigating the evolution of dust aggregates in the early Solar System, we developed two vacuum drop towers in which fragile dust aggregates with sizes up to ~10 cm and porosities up to 70% can be collided. One of the drop towers is primarily used for very low impact speeds down to below 0.01 m/sec and makes use of a double release mechanism. Collisions are recorded in stereo-view by two high-speed cameras, which fall along the glass vacuum tube in the center-of-mass frame of the two dust aggregates. The other free-fall tower makes use of an electromagnetic accelerator that is capable of gently accelerating dust aggregates to up to 5 m/sec. In combination with the release of another dust aggregate to free fall, collision speeds up to ~10 m/sec can be achieved. Here, two fixed high-speed cameras record the collision events. In both drop towers, the dust aggregates are in free fall during the collision so that they are weightless and match the conditions in the early Solar System.

We present a technique to achieve low-velocity to intermediate-velocity collisions between fragile dust aggregates in the laboratory. For this purpose, two vacuum drop-tower setups have been developed that allow collision velocities between &#60;0.01 and ~10 m/sec. The collision events are recorded by high-speed imaging.

For the purpose of investigating the evolution of dust aggregates in the early Solar System, we developed two vacuum drop towers in which fragile dust ...

SSVEP-based Experimental Procedure for Brain-Robot Interaction with Humanoid Robots

Brain-Robot Interaction (BRI), which provides an innovative communication pathway between human and a robotic device via brain signals, is prospective in helping the disabled in their daily lives. The overall goal of our method is to establish an SSVEP-based experimental procedure by integrating multiple software programs, such as OpenViBE, Choregraph, and Central software as well as user developed programs written in C++ and MATLAB, to enable the study of brain-robot interaction with humanoid robots.
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The overall goal of this method is to establish an SSVEP-based experimental procedure by integrating multiple software programs to enable the study of brain-robot interaction with humanoid robots, which is prospective in assisting the sick and elderly as well as performing unsanitary or dangerous jobs.

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Printing Fabrication of Bulk Heterojunction Solar Cells and In Situ Morphology Characterization

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Printing Fabrication of Bulk Heterojunction Solar Cells and In Situ Morphology Characterization

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Experimental Methodology for Estimation of Local Heat Fluxes and Burning Rates in Steady Laminar Boundary Layer Diffusion Flames

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We describe the use of micro-thermocouples to estimate local temperature gradients in steady laminar boundary layer diffusion flames. By extension of the Reynolds Analogy, local temperature gradients can be further used to estimate the local mass burning rates and heat fluxes in such flames with high accuracy.

Modeling the realistic burning behavior of condensed-phase fuels has remained out of reach, in part because of an inability to resolve the complex ...

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The authors present a method for fabricating stable white-light-emitting electrochemical cells utilizing emission from exciplexes formed between a blue-emitting fluorene polymer and aromatic amines.

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In Situ Visualization of the Phase Behavior of Oil Samples Under Refinery Process Conditions

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To help address production issues in refineries caused by the fouling of process units and lines, we have developed a setup as well as a method to ...

A Novel Method for In Situ Electromechanical Characterization of Nanoscale Specimens

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A Novel Method for In Situ Electromechanical Characterization of Nanoscale Specimens

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Indoor Experimental Assessment of the Efficiency and Irradiance Spot of the Achromatic Doublet on Glass ADG Fresnel Lens for Concentrating Photovoltaics

The achromatic doublet on glass (ADG) Fresnel lens makes use of two materials with differing dispersion to reduce chromatic aberration and increase attainable concentration. In this paper, a protocol for the complete characterization of the ADG Fresnel lens is presented.