M. S. P., D. G., D. V., and B. K. acknowledge support of the Biological and bioinspired structures for multispectral surveillance, funded by NATO SPS (NATO Science for Peace and Security) 2019-2022. B. K., D. V., B. B., D. G., and M. S. P. acknowledge funding provided bythe Institute of Physics Belgrade, through the institutional funding bythe Ministry of Education, Science, and Technological Development of theRepublic of Serbia. Additionally, B. K. acknowledges support from F R S - FNRS. M. P. acknowledges support from the Ministry of Education, Science and Technological Development of the Republic of Serbia, Contract number 451-03-9/2021-14/200026. S. R. M. was supported by a BEWARE Fellowship of the Walloon Region (Convention n&#176;2110034), as a postdoctoral researcher. T. V. acknowledges financial support from the Hercules Foundation. D.V., M.S.P., D.G., M.P., B.B., and B.K. acknowledge the support of the Office of Naval Research Global through the Research Grant N62902-22-1-2024.&#160;This study was conducted in partial fulfillment of the requirements for the PhD degree of Marina Simovi&#263; Pavlovi&#263; at the University of Belgrade, Faculty of Mechanical Engineering.

1. Precharacterization
<ol>
	<li>Perform a full precharacterization of the sample.
	<ol>
		<li>Perform all experiments on dry specimens purchased from a commercial source. Store the samples in the laboratory, in a dry and dark place, at room temperature.</li>
		<li>Prior to holographic measurements, perform a complete sample characterization by scanning electronic microscope (SEM), linear optical spectroscopy, and nonlinear optical microscopy (NOM)10 (Figure 1).</li>
		<li>In addition to the optical properties of samples measured by linear techniques, gather supplementary information with higher intensity laser beams that allow characterization of their nonlinear optical properties.</li>
		<li>Use the corresponding nonlinear optical susceptibilities to quantify the nonlinear optical response and form the basis of nonlinear optical techniques such as nondestructive multiphoton excitation fluorescence and second harmonic generation (SHG), which are used to characterize various biological samples.</li>
		<li>For the nonlinear chemical phenomena occurring in the oscillating BR reaction, carry out the study of interferometric monitoring of the in situ phase transition from state I to state II with the following concentrations of reactants: [CH2(COOH)2]0 = 0.0789 mol dm-3, [MnSO4]0 = 0.0075 mol dm-3, [HClO4]0 = 0.03 mol dm-3, [KIO3]0 = 0.0752 mol dm-3, and [H2O2]0 = 1.269 mol dm-3 (0 after the bracket stands for the initial concentration at the beginning of the process). Make the total volume used for the BR reaction equal to 2.5 mL. 
		NOTE: The concentration values used here are equal to the ones in the study by Pagnacco et al.8, but with reaction volume divided by 10.</li>
	</ol>
	</li>
	<li>Prepare the sample for the experiment.
	<ol>
		<li>Use wings of the Queen of Spain fritillary butterfly, I. lathonia, for this experiment. Place the wing on a hard surface and make a section with a 10 mm diameter cutter. Place the sample in the sample box, which can be any container with a lid.</li>
	</ol>
	</li>
</ol>
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/63676/63676fig01.jpg" /> 
Figure 1: Wavy cross-section of butterfly wing scale. The cross-section was recorded on a nonlinear optical scanning microscope (A,B). A SEM observation (C) of a wing of the Queen of Spain fritillary butterfly, I. lathonia,&#160;was also done. This figure has been modified from14. <a href="https://www.jove.com/files/ftp_upload/63676/63676fig01large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
2. Experimental setup
<ol>
	<li>Holographic setup 
	NOTE: The holographic interferometry measurements were performed with a tailor-made optical setup (Figure 2).
	<ol>
		<li>Adjust the laboratory temperature to be 23 &#176;C &#177; 0.2 &#176;C. Turn the laser on. Use a laser (details given in the Table of Materials) with an excitation wavelength of 532 nm for these holographic observations.</li>
		<li>Check the alignment of the optical elements (Figure 2). First, check that setup is made according to the scheme in Figure 2.</li>
		<li>Align the laser beam perfectly with the concave mirror M. Check and adjust the position of the optical beam expander (L).</li>
		<li>Determine the beam part that impinges on sample S and ensure that it forms a reflex beam O. Check if the rest of the beam is collected on a spherical mirror CM, to be used to generate the reference beam R. Check if the detector C is placed within the interference zone of the two specified beams. 
		NOTE: A complementary metal oxide semiconductor (CMOS) sensor is used as detector.</li>
		<li>Set up the cameras according to the instructions for the camera used. Set up an optical/photographic camera for the holographic experiment as shown in Figure 2 (C is the camera; details given in the Table of Materials). Set up a second optical/photographic camera to view visible changes in BR reaction and a thermal camera with a thermal resolution of 50 mK and a focal length of 13 mm above the optical table. 
		NOTE: The camera used in the holographic experiment does not use an objective lens; the light directly impinges on the chip.</li>
	</ol>
	</li>
	<li>Prepare the sample into holographic setup.
	<ol>
		<li>Prepare the wing sample as in step 1.2.1. Place the prepared sample on a round metal support with a diameter of 15 mm. The support has three existing holes for the screws to which the metal ring holding the sample is attached.</li>
		<li>Attach the ring to the support. Place the attached sample in the part of the sample mount located on the optical table.</li>
		<li>Prepare the sample for chemical reaction monitoring. On the optical table, in the intended place, place a support with a flat adhesive surface on which the cuvette/vessel will be placed.</li>
		<li>Prepare the reagent used to initialize the reaction as in step 1.1.5. Fill the reactants into the cuvette, and mix in cuvette in the following order of volumes and concentrations: 0.7 mL of 0.2817 mol dm-3 CH2(COOH)2; 0.5 mL of 0.0375 mol dm-3 MnSO4; 0.5 mL of 0.15 mol dm-3 HClO4; 0.5 mL of 0.376 mol dm-3 KIO3 ; and 0.3 mL of 10.575 mol dm-3 H2O2.</li>
		<li>Ensure that the total volume in the cuvette is 2.5 mL, and place it on the support in the setup.</li>
		<li>Set up additional instruments if needed. For monitoring the photophoretic effect, use an additional laser (details given in Table of Materials) for local heating.</li>
	</ol>
	</li>
</ol>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/63676/63676fig02.jpg" /> 
Figure 2: The holographic setup. The figure shows how the various components are arranged for the holographic experiment. Abbreviations: L1 = laser at 532 nm, L = biconvex lens, A = aperture, M = a flat mirror used to deflect the laser beam, CM = concave mirror, C = CMOS camera, S = butterfly wing section, R = reference beam, O = object beam. <a href="https://www.jove.com/files/ftp_upload/63676/63676fig02large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
3. Setup of the software used
NOTE: Home-built C++ software based on Fresnel approximation11 is used to analyze data from holographic experiments. The software developed for the presented study can be found at .12 The details of software cannot be published at the moment; however, additional information will be provided on request. Fresnel approximation is extremely useful in digital holography since it focuses on different surfaces and zooms in on the area of the first diffraction order, which contains complete information about the recorded scene.
<ol>
	<li>Turn on the computer and run the software. 
	NOTE: The step for running the software depends on the software itself. There is no commercial software for this purpose.</li>
</ol>
4. Perform the experiment
<ol>
	<li>Switch off the external lights. Carry out the whole experiment in a dark room.</li>
	<li>Synchronize the cameras by using a chosen interval. For this experiment, start the holographic camera after 60 s, and the two other cameras immediately after it, using either a software or manually.</li>
	<li>Press the recording buttons and define in the software when the recording starts.</li>
	<li>Induce dynamical changes in the system of interest. The method of initiation depends on the type of sample; in the case of photophoretic effect, externally heat the sample by using the available lasers: 450 nm, 532 nm, 660 nm, 980 nm. In the case of the BR reaction, start the reaction by mixing the chemical reactants. Observe the holographic experiment.</li>
	<li>Set the photographic and thermal camera to follow the whole experiment and determine the moment of the end of the holographic recording from the optical and thermal measurements.</li>
	<li>Pronounce the end of the process. The end of the recording is preprogrammed, according to the estimated duration of the process. For the BR reaction, use solidification as the end of the reaction. In the case of the photophoretic effect, there is no such specific moment. In any case, this step emphasizes the importance of triple recording.</li>
</ol>
5. Acquisition of results12
<ol>
	<li>Save the results. Precisely sort the files as a function of time for reconstructing holograms and deeper data analysis. 
	NOTE: In this step, the data is transferred from the camera used for holography to the computer (hard disk) in folders named after the shooting dates. Use copy/paste and rename buttons.</li>
	<li>Check the probe hologram for appropriate settings. In this way, the best settings are selected on the first hologram by looking at it, and then used for the reconstruction of all holograms.
	<ol>
		<li>Choose one hologram by clicking on one of them from the folder you previously made (step 5.1) and make a reconstruction by clicking on the Reconstruct button.</li>
		<li>Change the settings to achieve the best image and make the reconstruction again. Options for adjusting parameters such as sampling, offset, and Fresnel distance will appear on the screen (software menu). Repeat these steps until the best settings are defined.</li>
		<li>Perform the reconstructions. Choose all the holograms by clicking the Open File button and choosing all files. Apply the desired parameters for numerical reconstruction of holograms; they remain unchanged after the step 5.2.1, so do not perform any action this time.</li>
		<li>Carry out the reconstructions using the Reconstruct button, and the interferograms by inserting the file names in the start with/end with field and then by clicking the button Batch. The interferograms appear in the previously made folder (in step 5.1). 
		NOTE: After recording a series of holograms in time, the first hologram represents an unperturbed state, while the action of an external force causes subsequent holograms. It is necessary to reconstruct the holograms using shifted Fresnel transform13.</li>
		<li>Obtain the interferograms by subtraction (in terms of complex numbers) of a particular hologram in time with the first hologram obtained. 
		NOTE: This protocol allows observing the effect of the force on the object. The change in the interference pattern as a function of time is a consequence of deformation or displacement that occurs within the system during the measurement. These changes are used to monitor the system&#39;s dynamics at the nanoscale.</li>
	</ol>
	</li>
</ol>
6. Analyses of the results
<ol>
	<li>Perform a visual analysis as the first quality control step of the process. In this step, look for visible changes in interference pattern and try to match the changes in the interference pattern with results obtained by optical and thermal measurements.</li>
	<li>Perform a cross-examination of all recordings. In this second phase of the analysis, thoroughly analyze the images visually from both the optical and thermal cameras with the holographic reconstructions in order to reveal dynamics at the nanoscale. In this way, the reaction moment is seen simultaneously in holographic, thermal, and photographic images.</li>
	<li>Make a graphical representation of results based on numerical/software analysis and present them in the form of graphs (1D, 2D, or 3D), charts, histograms etc. After a complete analysis of results, draw conclusions and anticipate further research based on this.</li>
</ol>

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The authors declare no conflict of interests.

In the presented biophotonic study, it is shown that a novel holographic method can be used to detect minimal morphological displacement or deformation caused by low-level thermal radiation.
The most critical step in holographic measurement with biological samples is the preparation step. The preparation of the sample (cutting/gluing to match the size of the holder) depends on the sample&#39;s mechanical properties, and it is not possible to have a standard protocol for this step.
<p class...

To fully understand and notice all the unique phenomena in the nanoworld, it is crucial to employ techniques that are capable of revealing all details regarding structures and dynamics at the nanoscale. On this account, the unique combination of linear and nonlinear methods, combined with the power of holography to reveal the system&#39;s dynamics at the nanoscale are presented.
The described holographic technique can be viewed as the triple rec method (rec is the abbreviation for recording), since at a given time the signal is simultaneously recorded by a photographic camera, a thermal camera, and an interferometer. Linear and nonlinear optical spectroscopy and holography are well-known techniques, the fundamental principles of which are extensively described in the literature1,2.
To cut a long story short, holographic interferometry allows the comparison of wavefronts recorded at different moments in time to characterize the dynamics of the system. It was previously used to measure vibrational dynamics3,4. The power of holography as the simplest interferometry method is based on its ability to detect the smallest displacement within the system. First, we exploited holography to observe and reveal the photophoretic effect5 (i.e., the displacement of deformation of a nanostructure due to a light-induced thermal gradient), in different biological structures. For a true presentation of the method, representative samples were selected from a number of tested biological specimens6. Wings of the Queen of Spain fritillary butterfly, Issoria lathonia (Linnaeus, 1758; I. lathonia), were used in the framework of this study.
After having successfully demonstrated the occurrence of photophoresis at the nanoscale in biological tissues, a similar protocol was applied to monitor the spontaneous symmetry breaking process7 caused by a phase transition in an oscillatory chemical reaction. In this part, the phase transition from a low concentration of iodide and iodine (called state I) to a high concentration of iodide and iodine with solid iodine formation (defined as state II) that occurs in a chemically nonlinear BR reaction was studied8,9. Here, we reported for the first time a holographic approach that allows studying such a phase transition and spontaneous symmetry breaking dynamics at the nanoscale occurring in condensed systems.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Active Vibration Isolation, Four Optical Table Supports</td>
			<td>Thorlabs</td>
			<td>PTR502</td>
			<td>High Load Capacity: 2,500 kg, Height 600 mm</td>
		</tr>
		<tr>
			<td>Cuvette</td>
			<td></td>
			<td></td>
			<td>Standard glass cuvette</td>
		</tr>
		<tr>
			<td>Holographic camera (optical camera for holography)</td>
			<td>Cannon</td>
			<td>EOS 50D</td>
			<td>Sensor Size 22.3 x 14.9 mm; Pixel pitch 4.69 &#181;m; Max. resolution 4752 x 3168; JPEG file format</td>
		</tr>
		<tr>
			<td>Hydrogen peroxide, H2O2</td>
			<td>Merck (Darmstadt, Germany)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Laser</td>
			<td>Laser Quantum</td>
			<td>Torus 532 laser</td>
			<td>Wavelength 532 nm; Power 390 mW; Coherence length 10 m</td>
		</tr>
		<tr>
			<td>LED lasers</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Malonic acid, C3H4O4</td>
			<td>Acr<img alt="Equation 10" src="/files/ftp_upload/63676/63676eq10.png" />s Organics (Geel, Belgium)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Manganese sulphate,&#160; MnSO4</td>
			<td>Fluka (Buchs, Switzerlend)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Nonlinear optical microscope</td>
			<td>IPB</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Optical accessories</td>
			<td>Thorlab</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Optical spectroscope</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Optical table</td>
			<td>Thorlabs</td>
			<td>TOP450II PTR52509</td>
			<td>dimensions 2000*1250*310 mm</td>
		</tr>
		<tr>
			<td>Perchloric acid, HClO4</td>
			<td>Merck (Darmstadt, Germany)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Potassium iodate, KIO3</td>
			<td>Merck (Darmstadt, Germany)</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Software</td>
			<td></td>
			<td></td>
			<td>Home-build software made by one of the authors: Dusan Grujic. This software was conducted in partial fulfillment of the requirements for the PhD deegree of D.G.</td>
		</tr>
		<tr>
			<td>Thermal camera</td>
			<td>Flir</td>
			<td>A65</td>
			<td>640x512 pixel; Thermal resolution 50 mK</td>
		</tr>
		<tr>
			<td>Video camera</td>
			<td>Nikon</td>
			<td>1v3</td>
			<td>18.4 Mpixel; 60 fps</td>
		</tr>
	</tbody>
</table>

uncovering hidden dynamics of natural photonic structures using holographic imaging

In this method, the potential of optics and holography to uncover hidden details of a natural system's dynamical response at the nanoscale is exploited. In the first part, the optical and holographic studies of natural photonic structures are presented as well as conditions for the appearance of the photophoretic effect, namely, the displacement or deformation of a nanostructure due to a light-induced thermal gradient, at the nanoscale. This effect is revealed by real-time digital holographic interferometry monitoring the deformation of scales covering the wings of insects induced by temperature. The link between geometry and nanocorrugation that leads to the emergence of the photophoretic effect is experimentally demonstrated and confirmed. In the second part, it is shown how holography can be potentially used to uncover hidden details in the chemical system with nonlinear dynamics, such as the phase transition phenomenon that occurs in complex oscillatory Briggs-Rauscher (BR) reaction. The presented potential of holography at the nanoscale could open enormous possibilities for controlling and molding the photophoretic effect and pattern formation for various applications such as particle trapping and levitation, including the movement of unburnt hydrocarbons in the atmosphere and separation of different aerosols, decomposition of microplastics and fractionation of particles in general, and assessment of temperature and thermal conductivity of micron-size fuel particles.

A photophoretic effect was induced and monitored in a first experiment on the wing of a Morpho menelaus butterfly5. The effect was initiated by the action of LED lasers of different wavelengths (450 nm, 532 nm, 660 nm, and 980 nm). Here, the wings from an I. lathonia butterfly14 were used. After the recording procedure, the hologram image was reconstructed.
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Uncovering Hidden Dynamics of Natural Photonic Structures Using Holographic Imaging

The paper is primarily focused on the combined power of optical (linear and nonlinear) and holographic methods used to reveal phenomena at the nanoscale. The results obtained from the biophotonic and oscillatory chemical reactions' studies are given as representative examples, highlighting holography's ability to reveal dynamics at a nanoscale.

In this method, the potential of optics and holography to uncover hidden details of a natural system's dynamical response at the nanoscale is exploited. ...

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Chemistry

2.5K Views.  University of Belgrade. The paper is primarily focused on the combined power of optical (linear and nonlinear) and holographic methods used to reveal phenomena at the nanoscale. The results obtained from the biophotonic and oscillatory chemical reactions' studies are given as representative examples, highlighting holography's ability to reveal dynamics at a nanoscale.

Video: Uncovering Hidden Dynamics of Natural Photonic Structures Using Holographic Imaging

Analyzing Protein Dynamics Using Hydrogen Exchange Mass Spectrometry

All cellular processes depend on the functionality of proteins. Although the functionality of a given protein is the direct consequence of its unique amino acid sequence, it is only realized by the folding of the polypeptide chain into a single defined three-dimensional arrangement or more commonly into an ensemble of interconverting conformations. Investigating the connection between protein conformation and its function is therefore essential for a complete understanding of how proteins are able to fulfill their great variety of tasks. One possibility to study conformational changes a protein undergoes while progressing through its functional cycle is hydrogen-1H/2H-exchange in combination with high-resolution mass spectrometry (HX-MS). HX-MS is a versatile and robust method that adds a new dimension to structural information obtained by e.g. crystallography. It is used to study protein folding and unfolding, binding of small molecule ligands, protein-protein interactions, conformational changes linked to enzyme catalysis, and allostery. In addition, HX-MS is often used when the amount of protein is very limited or crystallization of the protein is not feasible. Here we provide a general protocol for studying protein dynamics with HX-MS and describe as an example how to reveal the interaction interface of two proteins in a complex. &#160;&#160;

Protein conformation and dynamics are key to understanding the relationship between protein structure and function. Hydrogen exchange coupled with high-resolution mass spectrometry is a versatile method to study the conformational dynamics of proteins as well as characterizing protein-ligand and protein-protein interactions, including contact interfaces and allosteric effects.

All cellular processes depend on the functionality of proteins. Although the functionality of a given protein is the direct consequence of its unique ...

Formation of Ordered Biomolecular Structures by the Self-assembly of Short Peptides

In nature, complex functional structures are formed by the self-assembly of biomolecules under mild conditions. Understanding the forces that control self-assembly and mimicking this process in vitro will bring about major advances in the areas of materials science and nanotechnology. Among the available biological building blocks, peptides have several advantages as they present substantial diversity, their synthesis in large scale is straightforward, and they can easily be modified with biological and chemical entities1,2. Several classes of designed peptides such as cyclic peptides, amphiphile peptides and peptide-conjugates self-assemble into ordered structures in solution. Homoaromatic dipeptides, are a class of short self-assembled peptides that contain all the molecular information needed to form ordered structures such as nanotubes, spheres and fibrils3-8. A large variety of these peptides is commercially available.
This paper presents a procedure that leads to the formation of ordered structures by the self-assembly of homoaromatic peptides. The protocol requires only commercial reagents and basic laboratory equipment. In addition, the paper describes some of the methods available for the characterization of peptide-based assemblies. These methods include electron and atomic force microscopy and Fourier-Transform Infrared Spectroscopy (FT-IR). Moreover, the manuscript demonstrates the blending of peptides (coassembly) and the formation of a &#34;beads on a string&#34;-like structure by this process.9 The protocols presented here can be adapted to other classes of peptides or biological building blocks and can potentially lead to the discovery of new peptide-based structures and to better control of their assembly.

This paper describes the formation of highly ordered peptide-based structures by the spontaneous process of self-assembly. The method utilizes commercially available peptides and common lab equipment. This technique can be applied to a large variety of peptides and may lead to the discovery of new peptide-based assemblies.

In nature, complex functional structures are formed by the self-assembly of biomolecules under mild conditions. Understanding the forces that control ...

Highly Stable, Functional Hairy Nanoparticles and Biopolymers from Wood Fibers: Towards Sustainable Nanotechnology

Nanoparticles, as one of the key materials in nanotechnology and nanomedicine, have gained significant importance during the past decade. While metal-based nanoparticles are associated with synthetic and environmental hassles, cellulose introduces a green, sustainable alternative for nanoparticle synthesis. Here, we present the chemical synthesis and separation procedures to produce new classes of hairy nanoparticles (bearing both amorphous and crystalline regions) and biopolymers based on wood fibers. Through periodate oxidation of soft wood pulp, the glucose ring of cellulose is opened at the C2-C3 bond to form 2,3-dialdehyde groups. Further heating of the partially oxidized fibers (e.g., T = 80 &#176;C) results in three products, namely fibrous oxidized cellulose, sterically stabilized nanocrystalline cellulose (SNCC), and dissolved dialdehyde modified cellulose (DAMC), which are well separated by intermittent centrifugation and co-solvent addition. The partially oxidized fibers (without heating) were used as a highly reactive intermediate to react with chlorite for converting almost all aldehyde to carboxyl groups. Co-solvent precipitation and centrifugation resulted in electrosterically stabilized nanocrystalline cellulose (ENCC) and dicarboxylated cellulose (DCC). The aldehyde content of SNCC and consequently surface charge of ENCC (carboxyl content) were precisely controlled by controlling the periodate oxidation reaction time, resulting in highly stable nanoparticles bearing more than 7 mmol functional groups per gram of nanoparticles (e.g., as compared to conventional NCC bearing &#60;&#60; 1 mmol functional group/g). Atomic force microscopy (AFM), transmission electron microscopy (TEM), and scanning electron microscopy (SEM) attested to the rod-like morphology. Conductometric titration, Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), dynamic light scattering (DLS), electrokinetic-sonic-amplitude (ESA) and acoustic attenuation spectroscopy shed light on the superior properties of these nanomaterials.

Synthesis schemes to prepare highly stable wood fiber-based hairy nanoparticles and functional cellulose-based biopolymers have been detailed.

Nanoparticles, as one of the key materials in nanotechnology and nanomedicine, have gained significant importance during the past decade. While ...

Laboratory Production of Biofuels and Biochemicals from a Rapeseed Oil through Catalytic Cracking Conversion

The work is based on a reported study which investigates the processability of canola oil (bio-feed) in the presence of bitumen-derived heavy gas oil (HGO) for production of transportation fuels through a fluid catalytic cracking (FCC) route. Cracking experiments are performed with a fully automated reaction unit at a fixed weight hourly space velocity (WHSV) of 8 hr-1, 490-530 &#176;C, and catalyst/oil ratios of 4-12 g/g. When a feed is in contact with catalyst in the fluid-bed reactor, cracking takes place generating gaseous, liquid, and solid products. The vapor produced is condensed and collected in a liquid receiver at -15 &#176;C. The non-condensable effluent is first directed to a vessel and is sent, after homogenization, to an on-line gas chromatograph (GC) for refinery gas analysis. The coke deposited on the catalyst is determined in situ by burning the spent catalyst in air at high temperatures. Levels of CO2 are measured quantitatively via an infrared (IR) cell, and are converted to coke yield. Liquid samples in the receivers are analyzed by GC for simulated distillation to determine the amounts in different boiling ranges, i.e., IBP-221 &#176;C (gasoline), 221-343 &#176;C (light cycle oil), and 343 &#176;C+ (heavy cycle oil). Cracking of a feed containing canola oil generates water, which appears at the bottom of a liquid receiver and on its inner wall. Recovery of water on the wall is achieved through washing with methanol followed by Karl Fischer titration for water content. Basic results reported include conversion (the portion of the feed converted to gas and liquid product with a boiling point below 221 &#176;C, coke, and water, if present) and yields of dry gas (H2-C2's, CO, and CO2), liquefied petroleum gas (C3-C4), gasoline, light cycle oil, heavy cycle oil, coke, and water, if present.

This paper presents an experimental method to produce biofuels and biochemicals from canola oil mixed with a fossil-based feed in the presence of a catalyst at mild temperatures. Gaseous, liquid, and solid products from a reaction unit are quantified and characterized. Conversion and individual product yields are calculated and reported.

The work is based on a reported study which investigates the processability of canola oil (bio-feed) in the presence of bitumen-derived heavy gas oil ...

Fabrication and Testing of Photonic Thermometers

In recent years, a push for developing novel silicon photonic devices for telecommunications has generated a vast knowledge base that is now being leveraged for developing sophisticated photonic sensors. Silicon photonic sensors seek to exploit the strong confinement of light in nano-waveguides to transduce changes in physical state to changes in resonance frequency. In the case of thermometry, the thermo-optic coefficient, i.e., changes in refractive index due to temperature, causes the resonant frequency of the photonic device such as a Bragg grating to drift with temperature. We are developing a suite of photonic devices that leverage recent advances in telecom compatible light sources to fabricate cost-effective photonic temperature sensors, which can be deployed in a wide variety of settings ranging from controlled laboratory conditions, to the noisy environment of a factory floor or a residence. In this manuscript, we detail our protocol for the fabrication and testing of photonic thermometers.

We describe the process of fabrication and testing of photonic thermometers.

In recent years, a push for developing novel silicon photonic devices for telecommunications has generated a vast knowledge base that is now being ...

Aerosol-assisted Chemical Vapor Deposition of Metal Oxide Structures: Zinc Oxide Rods

Whilst columnar zinc oxide (ZnO) structures in the form of rods or wires have been synthesized previously by different liquid- or vapor-phase routes, their high cost production and/or incompatibility with microfabrication technologies, due to the use of pre-deposited catalyst-seeds and/or high processing temperatures exceeding 900 &#176;C, represent a drawback for a widespread use of these methods. Here, however, we report the synthesis of ZnO rods via a non-catalyzed vapor-solid mechanism enabled by using an aerosol-assisted chemical vapor deposition (CVD) method at 400 &#176;C with zinc chloride (ZnCl2) as the precursor and ethanol as the carrier solvent. This method provides both single-step formation of ZnO rods and the possibility of their direct integration with various substrate types, including silicon, silicon-based micromachined platforms, quartz, or high heat resistant polymers. This potentially facilitates the use of this method at a large-scale, due to its compatibility with state-of-the-art microfabrication processes for device manufacture. This report also describes the properties of these structures (e.g., morphology, crystalline phase, optical band gap, chemical composition, electrical resistance) and validates its gas sensing functionality towards carbon monoxide.

Columnar zinc oxide structures in the form of rods are synthesized via aerosol-assisted chemical vapor deposition without the use of pre-deposited catalyst-seed particles. This method is scalable and compatible with various substrates based on either silicon, quartz or polymers.

Whilst columnar zinc oxide (ZnO) structures in the form of rods or wires have been synthesized previously by different liquid- or vapor-phase routes, ...

Minimum Burning Pressures of Water-based Emulsion Explosives

This manuscript describes a protocol to measure the minimum pressure required for sustained burning of water-based emulsion explosives. Pumping water-based emulsion explosives for blasting applications can be very hazardous, as demonstrated by a number of pump accidents around the globe in the last decades, including some that resulted in fatalities. In Canada, the recognition of this hazard has led to the development of pumping guidelines that were endorsed by both the explosives industry and the Explosive Regulatory Division of the Canadian government. In these guidelines, it was noted that the minimum burning pressures (MBP) measured in a laboratory would provide a good guide to characterize the behaviour of these products in pumping systems. The same guidelines also call for the design of pump systems that prevent, whenever possible, pressures from exceeding the MBP of the product being pumped. At the time of publication of these guidelines, a methodology existed for measuring such MBP values but it had never been validated to measure the MBP of ammonium nitrate water-based emulsions (AWEs). AWEs are now used much more widely than any other water-based explosives and precursors in on-site bulk loading operations.
The Canadian Explosives Research Laboratory (CanmetCERL) has been conducting research over the last ten years to develop a validated testing protocol to measure and interpret representative MBP values for AWEs. The test, as it is performed today, will be described and the critical components will be justified by reference to recent published data. Results of MBP measurements, for a range of AWE products, will be presented. Inclusion of the MBP test in the test standards for the authorization of high explosives in Canada will also be discussed.

We present an apparatus based on hot-wire ignition in a pressurized enclosure and an associated methodology to measure the minimum pressure required to induce sustained combustion in water-based emulsion explosives. This method improves product characterization to allow one to use them more safely during pumping and mixing operations.

This manuscript describes a protocol to measure the minimum pressure required for sustained burning of water-based emulsion explosives. Pumping ...

Novel Techniques for Observing Structural Dynamics of Photoresponsive Liquid Crystals

We discuss in this article the experimental measurements of the molecules in liquid crystal (LC) phase using the time-resolved infrared (IR) vibrational spectroscopy and time-resolved electron diffraction. Liquid crystal phase is an important state of matter that exists between the solid and liquid phases and it is common in natural systems as well as in organic electronics. Liquid crystals are orientationally ordered but loosely packed, and therefore, the internal conformations and alignments of the molecular components of LCs can be modified by external stimuli. Although advanced time-resolved diffraction techniques have revealed picosecond-scale molecular dynamics of single crystals and polycrystals, direct observations of packing structures and ultrafast dynamics of soft materials have been hampered by blurry diffraction patterns. Here, we report time-resolved IR vibrational spectroscopy and electron diffractometry to acquire ultrafast snapshots of a columnar LC material bearing a photoactive core moiety. Differential-detection analyses of the combination of time-resolved IR vibrational spectroscopy and electron diffraction are powerful tools for characterizing structures and photoinduced dynamics of soft materials.

Here, we present the protocols of differential-detection analyses of time-resolved infrared vibrational spectroscopy and electron diffraction which enable observations of the deformations of local structures around photoexcited molecules in a columnar liquid crystal, giving an atomic perspective on the relationship between the structure and the dynamics of this photoactive material.

We discuss in this article the experimental measurements of the molecules in liquid crystal (LC) phase using the time-resolved infrared (IR) vibrational ...

Employing Pressurized Hot Water Extraction (PHWE) to Explore Natural Products Chemistry in the Undergraduate Laboratory

A recently developed pressurized hot water extraction (PHWE) method which utilizes an unmodified household espresso machine to facilitate natural products research has also found applications as an effective teaching tool. Specifically, this technique has been used to introduce second- and third-year undergraduates to aspects of natural products chemistry in the laboratory. In this report, two experiments are presented: the PHWE of eugenol and acetyleugenol from cloves and the PHWE of seselin and (+)-epoxysuberosin from the endemic Australian plant species Correa reflexa. By employing PHWE in these experiments, the crude clove extract, enriched in eugenol and acetyleugenol, was obtained in 4-9% w/w from cloves by second-year undergraduates and seselin and (+)-epoxysuberosin were isolated in yields of up to 1.1% w/w and 0.9% w/w from C. reflexa by third-year students. The former exercise was developed as a replacement for the traditional steam distillation experiment providing an introduction to extraction and separation techniques, while the latter activity featured guided-inquiry teaching methods in an effort to simulate natural products bioprospecting. This primarily derives from the rapid nature of this PHWE technique relative to traditional extraction methods that are often incompatible with the time constraints associated with undergraduate laboratory experiments. This rapid and practical PHWE method can be used to efficiently isolate various classes of organic molecules from a range of plant species. The complementary nature of this technique relative to more traditional methods has also been demonstrated previously.

Employing Pressurized Hot Water Extraction PHWE to Explore Natural Products Chemistry in the Undergraduate Laboratory

Here, we employ a pressurized hot water extraction (PHWE) method, which utilizes an unmodified household espresso machine to introduce undergraduates to natural products chemistry in the laboratory. Two experiments are presented: PHWE of eugenol and acetyleugenol from cloves and PHWE of seselin and (+)-epoxysuberosin from the Australian plant Correa reflexa.

A recently developed pressurized hot water extraction (PHWE) method which utilizes an unmodified household espresso machine to facilitate natural products ...

DNA Origami-Mediated Substrate Nanopatterning of Inorganic Structures for Sensing Applications

Structural DNA nanotechnology provides a viable route for building from the bottom-up using DNA as construction material. The most common DNA nanofabrication technique is called DNA origami, and it allows high-throughput synthesis of accurate and highly versatile structures with nanometer-level precision. Here, it is shown how the spatial information of DNA origami can be transferred to metallic nanostructures by combining the bottom-up DNA origami with the conventionally used top-down lithography approaches. This allows fabrication of billions of tiny nanostructures in one step onto selected substrates. The method is demonstrated using bowtie DNA origami to create metallic bowtie-shaped antenna structures on silicon nitride or sapphire substrates. The method relies on the selective growth of a silicon oxide layer on top of the origami deposition substrate, thus resulting in a patterning mask for following lithographic steps. These nanostructure-equipped surfaces can be further used as molecular sensors (e.g., surface-enhanced Raman spectroscopy (SERS)) and in various other optical applications at the visible wavelength range owing to the small feature sizes (sub-10 nm). The technique can be extended to other materials through methodological modifications; therefore, the resulting optically active surfaces may find use in development of metamaterials and metasurfaces.

Here, we describe a protocol to create discrete and accurate inorganic nanostructures on substrates using DNA origami shapes as guiding templates. The method is demonstrated by creating plasmonic gold bowtie-shaped antennas on a transparent substrate (sapphire).