The authors wish to thank the Defence Science and Technology Laboratory for funding the published work.

<ol>
	<li>Esparza, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Blast+measurements+and+equivalency+for+spherical+charges+at+small+scaled+distances.">Blast measurements and equivalency for spherical charges at small scaled distances.</a> Int. J. Impact Eng. 4 (1), 23-40 (1986).</li><li>Kingery, C. N., Bulmash, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=ARBRL-TR-02555.">ARBRL-TR-02555.</a> Airblast parameters from TNT spherical air burst and hemispherical surface burst. , (1984).</li><li>Hyde, D. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Conventional weapons program (ConWep). , (1991).</li><li>Randers-Pehrson, G., Bannister, K. 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M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+response+of+small+scale+rigid+targets+to+shallow+buried+explosive+detonations.">The response of small scale rigid targets to shallow buried explosive detonations.</a> Int. J. Impact Eng. 38 (11), 882-891 (2011).</li><li>Ehrgott, J. Q., Rhett, R. G., Akers, S. A., Rickman, D. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Design+and+fabrication+of+an+impulse+measurement+device+to+quantify+the+blast+environment+from+a+near-surface+detonation+in+soil.">Design and fabrication of an impulse measurement device to quantify the blast environment from a near-surface detonation in soil.</a> Experimental Techniques. 35 (3), 51-62 (2011).</li><li>Pope, D. J., Tyas, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+hydrocode+modelling+techniques+to+predict+loading+parameters+from+free+air+hemispherical+explosive+charges.">Use of hydrocode modelling techniques to predict loading parameters from free air hemispherical explosive charges.</a> , (2002).</li><li>Clarke, S. D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Repeatability+of+buried+charge+testing.">Repeatability of buried charge testing.</a> , (2014).</li><li>Clarke, S. D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+large+scale+experimental+approach+to+the+measurement+of+spatially+and+temporally+localised+loading+from+the+detonation+of+shallow-buried+explosives.">A large scale experimental approach to the measurement of spatially and temporally localised loading from the detonation of shallow-buried explosives.</a> Meas Sci Technol. 26, 015001 (2015).</li><li>Hopkinson, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Method+of+Measuring+the+Pressure+Produced+in+the+Detonation+of+High+Explosives+or+by+the+Impact+of+Bullets.">A Method of Measuring the Pressure Produced in the Detonation of High Explosives or by the Impact of Bullets.</a> Philos. Trans. R. Soc. (London) A. 213, 437-456 (1914).</li><li>Rigby, S. E., Tyas, A., Fay, S. D., Clarke, S. D., Warren, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Validation+of+semi-empirical+blast+pressure+predictions+for+far+field+explosions+-+is+there+inherent+variability+in+blast+wave+parameters?.">Validation of semi-empirical blast pressure predictions for far field explosions - is there inherent variability in blast wave parameters?.</a> , (2014).</li><li>Rigby, S. E., Tyas, A., Bennett, T., Clarke, S. D., Fay, S. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+negative+phase+of+the+blast+load.">The negative phase of the blast load.</a> Int. J. of Protective Structures. 5 (1), 1-20 (2014).</li><li>Rigby, S. E., Fay, S. D., Tyas, A., Warren, J. A., Clarke, S. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Angle+of+incidence+effects+on+far-field+positive+and+negative+phase+blast+parameters.">Angle of incidence effects on far-field positive and negative phase blast parameters.</a> Int. J. of Protective Structures. 6 (1), 23-42 (2015).</li><li>Tyas, A., Warren, J., Bennett, T., Fay, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Prediction+of+clearing+effects+in+far-field+blast+loading+of+finite+targets.">Prediction of clearing effects in far-field blast loading of finite targets.</a> Shock Waves. 21 (2), 111-119 (2011).</li><li>Tyas, A., Watson, A. 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The authors have nothing to disclose.

Utilizando el protocolo descrito anteriormente, los autores han demostrado que es posible obtener mediciones de alta fidelidad de la carga altamente variando de una carga explosiva, utilizando una matriz de barras de presión de Hopkinson. El uso de la rutina de interpolación esbozó las historias de tiempo de presión discretos se puede transformar en un frente de choque continua que se puede utilizar directamente como la función de carga en el modelado numérico o como datos de validación para la salida de tales mo...

La caracterización de la salida de cargas explosivas tiene muchos beneficios, tanto militares (defensa contra enterrado artefactos explosivos improvisados ​​en zonas de conflicto actuales) y civiles (el diseño de componentes estructurales). En los últimos tiempos este tema ha sido objeto de considerable atención. Gran parte del conocimiento adquirido ha dirigido a la cuantificación de la salida de cargos para permitir el diseño de estructuras de protección más eficaces. El principal problema aquí es que si las mediciones realizadas no son de alta fidelidad a continuación, los mecanismos de transferencia de carga en estos eventos explosivos siguen sin estar claros. Esto a su vez conduce a problemas de validación de modelos numéricos que dependen de estas medidas para la validación. El término de campo cercano se utiliza para describir explosiones con distancias a escala, Z, menos de ~ 1 m / kg 1/3, donde Z = R / W 1/3, R es la distancia desde el centro del explosivo, y W se expresa la masa de la cargacomo una masa equivalente de TNT. En este régimen de la carga se caracteriza típicamente por extremadamente alta magnitud, temporal cargas no uniformes altamente espacial y. Instrumentos robustos, por lo tanto se requiere para medir las presiones extremas asociadas con la carga de campo cercano. A distancias en escala Z &lt;0,4 m / kg 1/3, mediciones directas de los parámetros hornos son inexistentes o muy pocos 1 y los datos predictivos semi-empíricos para esta gama se basa casi por completo en estudios paramétricos. Esto implica el uso de las predicciones semi-empíricas dadas por Kingery y Bulmash 2, que está fuera del alcance previsto del autor. Mientras que las herramientas basadas en estas predicciones 3,4 permiten excelentes estimaciones de primer orden de carga que no captan plenamente la mecánica de los eventos de campo cercano, que son el foco de la investigación actual. Mediciones de campo próximo hornos tienen en los últimos tiempos se centró en la cuantificación de la output de cargas enterradas. Las metodologías empleadas varían de evaluar la deformación causada a un objetivo estructural 5-7 para la medición directa de impulso mundial 8-13. Estos métodos proporcionan información valiosa para la validación de diseños de protectores del sistema, pero no son capaces de investigar a fondo los mecanismos de transferencia de carga. Se pueden realizar pruebas tanto a escala de laboratorio (1/10 escala completa), o por lo cerca de la escala completa (&gt; 1/4), con razones prácticas como el control de profundidad de enterramiento o asegurando que no forma inherente del frente de choque se genera por la uso de detonadores en lugar de cargas desnudos 14. Con cargas enterradas las condiciones del suelo tienen que ser muy controlado para garantizar la repetibilidad de la prueba 15. Independiente de la si la carga se coloca en el aire libre o está enterrado, el problema más fundamental en la medición de la explosión resultante es asegurar la validez de las mediciones realizadas por el deplo instrumentaciónyed. En el aparato de prueba diseñada 16 una placa de destino &#39;rígida&#39; fijo se utiliza para proteger las barras de presión de Hopkinson 17 (HPBs), mientras que al mismo tiempo asegurar que los extremos de las barras sólo pueden registrar las presiones plenamente reflejadas. Los autores han demostrado previamente que la medición de la presión reflejada desde un objetivo rígido es más preciso y repetible de incidente, o mediciones &#39;de campo libre&#39; 18-20. La geometría de esta placa es tal que cualquier alivio de la presión generada en la limpieza o el flujo alrededor del borde 21 de destino sería insignificante. Este nuevo aparato de prueba se ha construido a escala 1/4. En este control estricto escala sobre las condiciones de enterramiento y los explosivos se puede asegurar, con el tamaño de la carga a gran escala de 5 kg reducido para 78 g, a una profundidad de enterramiento de 25 mm.

<table border="0" cellpadding="0" cellspacing="0" width="573">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Load Cell</td>
			<td style="width:71px;">RDP</td>
			<td style="width:119px;">RSL0960</td>
			<td style="width:167px;">This is only indicative, the exact load cell should be able to resolve the required loading</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Steel target plate / HPBs</td>
			<td style="width:71px;">Garratts&#160;</td>
			<td style="width:119px;">N/A</td>
			<td>Fabricated to order</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Strain gauge</td>
			<td style="width:71px;">Kyowa</td>
			<td>KSP-2-120-E4</td>
			<td>To use with steel HPBs</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Cyanoacrylate</td>
			<td style="width:71px;">Kyowa</td>
			<td>CC-33-A</td>
			<td>Check with manufacturer depending on mar material to be used</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Digital Oscilloscope</td>
			<td style="width:71px;">TiePie</td>
			<td>HS4 16-bit Handyscopes&#160;</td>
			<td>6 used in parallel in current testing</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Leighton Buzzard sand</td>
			<td style="width:71px;">Garside sands</td>
			<td style="width:119px;">Garside 14/25</td>
			<td>Uniform silica sand&#160;</td>
		</tr>
	</tbody>
</table>

blast quantification using hopkinson pressure bars

De campo cercano medición de la carga explosiva presenta un problema para muchos tipos de sensores, ya que deben soportar ambientes muy agresivos y ser capaz de medir presiones de hasta varios cientos de megapascales. En este sentido, la simplicidad de la barra de presión de Hopkinson tiene una gran ventaja en que, si bien al final de medición de la barra de Hopkinson puede aguantar y se expone a condiciones duras, el indicador de tensión montado en la barra puede ser colocada a cierta distancia. Esto permite que las carcasas protectoras para ser utilizados que proteger el medidor de deformación, pero no interfiere con la adquisición de medición. El uso de una matriz de barras de presión permite que los historiales de tiempo de presión en puntos conocidos discretos a medir. En este artículo también describe la rutina de interpolación utilizado para derivar las historias de tiempo de presión en los lugares de la ONU-instrumentado en el plano de interés. Actualmente la técnica se ha utilizado para medir la carga de explosivos de gran potencia en el aire libre y enterrados superficialmente en distintos tipos de suelo.

Un marco de reacción efectiva rígida debe ser proporcionada. En la prueba de la corriente de un impulso impartido total de varios cientos de Newton-segundos necesita ser resistido con una desviación mínima. Una ilustración de la trama de reacción rígida utilizada se da en la Figura 1. En cada cuadro de una placa de acero de 50 mm aceptora se ha echado en la base de las vigas transversales. Mientras que no se requiere de forma explícita, esto permite una fácil fi...

Watch this Scientific Journal Video about Blast Quantification Using Hopkinson Pressure Bars at JoVE.com

Blast Quantification Using Hopkinson Pressure Bars

This protocol details the use of Hopkinson pressure bars to measure reflected blast loading from near-field explosive events. It is capable of interpolating a pressure-time history at any point on a reflective boundary and as such can be used to fully characterize the spatial and temporal variations in loading produced.

Explosión Cuantificación Utilizando listones de presión de Hopkinson

Near-field blast load measurement presents an issue to many sensor types as they must endure very aggressive environments and be able to measure pressures ...

blast-quantification-using-hopkinson-pressure-bars

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Strength of Concrete

SCIENTISTS IN ACTION

8.9K vistas.  University of Sheffield. This protocol details the use of Hopkinson pressure bars to measure reflected blast loading from near-field explosive events. It is capable of interpolating a pressure-time history at any point on a reflective boundary and as such can be used to fully characterize the spatial and temporal variations in loading produced.

Video: Blast Quantification Using Hopkinson Pressure Bars

Synthesis and Microdiffraction at Extreme Pressures and Temperatures

High pressure compounds and polymorphs are investigated for a broad range of purposes such as determine structures and processes of deep planetary interiors, design materials with novel properties, understand the mechanical behavior of materials exposed to very high stresses as in explosions or impacts. Synthesis and structural analysis of materials at extreme conditions of pressure and temperature entails remarkable technical challenges. In the laser heated diamond anvil cell (LH-DAC), very high pressure is generated between the tips of two opposing diamond anvils forced against each other; focused infrared laser beams, shined through the diamonds, allow to reach very high temperatures on samples absorbing the laser radiation. When the LH-DAC is installed in a synchrotron beamline that provides extremely brilliant x-ray radiation, the structure of materials under extreme conditions can be probed in situ. LH-DAC samples, although very small, can show highly variable grain size, phase and chemical composition. In order to obtain the high resolution structural analysis and the most comprehensive characterization of a sample, we collect diffraction data in 2D grids and combine powder, single crystal and multigrain diffraction techniques. Representative results obtained in the synthesis of a new iron oxide, Fe4O5 1 will be shown.

The laser heated diamond anvil cell combined with synchrotron micro-diffraction techniques allows researchers to explore the nature and properties of new phases of matter at extreme pressure and temperature (PT) conditions. Heterogeneous samples can be characterized in situ under high pressure by 2D mapping and combined powder, single-crystal and multigrain diffraction approaches.

Síntesis y microdifracción a presiones y temperaturas extremas

High pressure compounds and polymorphs are investigated for a broad range of purposes such as determine structures and processes of deep planetary ...

Investigación

Ingeniería

How to Ignite an Atmospheric Pressure Microwave Plasma Torch without Any Additional Igniters

This movie shows how an atmospheric pressure plasma torch can be ignited by microwave power with no additional igniters. After ignition of the plasma, a stable and continuous operation of the plasma is possible and the plasma torch can be used for many different applications. On one hand, the hot (3,600 K gas temperature) plasma can be used for chemical processes and on the other hand the cold afterglow (temperatures down to almost RT) can be applied for surface processes. For example chemical syntheses are interesting volume processes. Here the microwave plasma torch can be used for the decomposition of waste gases which are harmful and contribute to the global warming but are needed as etching gases in growing industry sectors like the semiconductor branch. Another application is the dissociation of CO2. Surplus electrical energy from renewable energy sources can be used to dissociate CO2 to CO and O2. The CO can be further processed to gaseous or liquid higher hydrocarbons thereby providing chemical storage of the energy, synthetic fuels or platform chemicals for the chemical industry. Applications of the afterglow of the plasma torch are the treatment of surfaces to increase the adhesion of lacquer, glue or paint, and the sterilization or decontamination of different kind of surfaces. The movie will explain how to ignite the plasma solely by microwave power without any additional igniters, e.g., electric sparks. The microwave plasma torch is based on a combination of two resonators &#8212; a coaxial one which provides the ignition of the plasma and a cylindrical one which guarantees a continuous and stable operation of the plasma after ignition. The plasma can be operated in a long microwave transparent tube for volume processes or shaped by orifices for surface treatment purposes.

This movie shows how an atmospheric plasma torch can be ignited by microwaves with no additional igniters and provides a stable and continuous plasma operation suitable for plenty of applications.

Cómo Encender una presión atmosférica de microondas de la antorcha de plasma sin ningún Encendedores adicionales

This movie shows how an atmospheric pressure plasma torch can be ignited by microwave power with no additional igniters. After ignition of the plasma, a ...

The Measurement of Unsteady Surface Pressure Using a Remote Microphone Probe

Microphones are widely applied to measure pressure fluctuations at the walls of solid bodies immersed in turbulent flows. Turbulent motions with various characteristic length scales can result in pressure fluctuations over a wide frequency range. This property of turbulence requires sensing devices to have sufficient sensitivity over a wide range of frequencies. Furthermore, the small characteristic length scales of turbulent structures require small sensing areas and the ability to place the sensors in very close proximity to each other. The complex geometries of the solid bodies, often including large surface curvatures or discontinuities, require the probe to have the ability to be set up in very limited spaces. The development of a remote microphone probe, which is inexpensive, consistent, and repeatable, is described in the present communication. It allows for the measurement of pressure fluctuations with high spatial resolution and dynamic response over a wide range of frequencies. The probe is small enough to be placed within the interior of typical wind tunnel models. The remote microphone probe includes a small, rigid, and hollow tube that penetrates the model surface to form the sensing area. This tube is connected to a standard microphone, at some distance away from the surface, using a "T" junction. An experimental method is introduced to determine the dynamic response of the remote microphone probe. In addition, an analytical method for determining the dynamic response is described. The analytical method can be applied in the design stage to determine the dimensions and properties of the RMP components.

Here, we present a protocol to measure, with high spatial resolution, the unsteady surface pressure in turbulent flows. This method demonstrates the construction of a remote microphone probe (RMP) and the determination of its frequency-dependent, complex transfer function. An analytical determination of the dynamic response is presented and validated.

La medición de la presión en superficie inestable con una pinza de micrófono remoto

Microphones are widely applied to measure pressure fluctuations at the walls of solid bodies immersed in turbulent flows. Turbulent motions with various ...

An Atmospheric Pressure Plasma Setup to Investigate the Reactive Species Formation

Non-thermal atmospheric pressure (&#39;cold&#39;) plasmas have received increased attention in recent years due to their significant biomedical potential. The reactions of cold plasma with the surrounding atmosphere yield a variety of reactive species, which can define its effectiveness. While efficient development of cold plasma therapy requires kinetic models, model benchmarking needs empirical data. Experimental studies of the source of reactive species detected in aqueous solutions exposed to plasma are still scarce. Biomedical plasma is often operated with He or Ar feed gas, and a specific interest lies in investigation of the reactive species generated by plasma with various gas admixtures (O2, N2, air, H2O vapor, etc.) Such investigations are very complex due to difficulties in controlling the ambient atmosphere in contact with the plasma effluent. In this work, we addressed common issues of &#39;high&#39; voltage kHz frequency driven plasma jet experimental studies. A reactor was developed allowing the exclusion of ambient atmosphere from the plasma-liquid system. The system thus comprised the feed gas with admixtures and the components of the liquid sample. This controlled atmosphere allowed the investigation of the source of the reactive oxygen species induced in aqueous solutions by He-water vapor plasma. The use of isotopically labelled water allowed distinguishing between the species originating in the gas phase and those formed in the liquid. The plasma equipment was contained inside a Faraday cage to eliminate possible influence of any external field. The setup is versatile and can aid in further understanding the cold plasma-liquid interactions chemistry.

An experimental setup was created for the helium-operated kHz frequency plasma jet. The setup includes a cage for the plasma power supply and jet and an in-house built reactor to monitor plasma-induced reactive species without the interference of the ambient atmosphere.

Una instalación de plasma a presión atmosférica para investigar la formación de especies reactivas

Non-thermal atmospheric pressure (&#39;cold&#39;) plasmas have received increased attention in recent years due to their significant biomedical potential. ...

Two-way Valorization of Blast Furnace Slag: Synthesis of Precipitated Calcium Carbonate and Zeolitic Heavy Metal Adsorbent

The aim of this work is to present a zero-waste process for storing CO2 in a stable and benign mineral form while producing zeolitic minerals with sufficient heavy metal adsorption capacity. To this end, blast furnace slag, a residue from iron-making, is utilized as the starting material. Calcium is selectively extracted from the slag by leaching with acetic acid (2 M CH3COOH) as the extraction agent. The filtered leachate is subsequently physico-chemically purified and then carbonated to form precipitated calcium carbonate (PCC) of high purity (&lt;2 wt% non-calcium impurities, according to ICP-MS analysis). Sodium hydroxide is added to neutralize the regenerated acetate. The morphological properties of the resulting calcitic PCC are tuned for its potential application as a filler in papermaking. In parallel, the residual solids from the extraction stage are subjected to hydrothermal conversion in a caustic solution (2 M NaOH) that leads to the predominant formation of a particular zeolitic mineral phase (detected by XRD), namely analcime (NaAlSi2O6&#8729;H2O). Based on its ability to adsorb Ni2+, as reported from batch adsorption experiments and ICP-OES analysis, this product can potentially be used in wastewater treatment or for environmental remediation applications.

A protocol for the parallel production of precipitated calcium carbonate and zeolitic material from blast furnace slag via mineral carbonation and alkaline hydrothermal conversion, respectively, is presented. The performance of the zeolitic material towards nickel adsorption is tested.

Dos vías de valorización de escoria de alto horno: Síntesis de carbonato de calcio precipitado y zeolíticos adsorbente de metales pesados

The aim of this work is to present a zero-waste process for storing CO2 in a stable and benign mineral form while producing zeolitic minerals with ...

Precision Milling of Carbon Nanotube Forests Using Low Pressure Scanning Electron Microscopy

A nanoscale fabrication technique appropriate for milling carbon nanotube (CNT) forests is described. The technique utilizes an environmental scanning electron microscope (ESEM) operating with a low pressure water vapor ambient. In this technique, a portion of the electron beam interacts with the water vapor in the vicinity of the CNT sample, dissociating the water molecules into hydroxyl radicals and other species by radiolysis. The remainder of the electron beam interacts with the CNT forest sample, making it susceptible to oxidation from the chemical products of radiolysis. This technique may be used to trim a selected region of an individual CNT, or it may be used to remove hundreds of cubic microns of material by adjusting ESEM parameters. The machining resolution is similar to the imaging resolution of the ESEM itself. The technique produces only small quantities of carbon residue along the boundaries of the cutting zone, with minimal effect on the native structural morphology of the CNT forest.

Low pressure scanning electron microscopy in a water vapor ambient is used to machine nanoscale to microscale features in carbon nanotube forests.

Fresado de precisión de nanotubos de carbono de los bosques El uso de baja presión de barrido Microscopía Electrónica

A nanoscale fabrication technique appropriate for milling carbon nanotube (CNT) forests is described. The technique utilizes an environmental scanning ...

Atmospheric Pressure Fabrication of Large-Sized Single-Layer Rectangular SnSe Flakes

Tin selenide (SnSe) belongs to the family of layered metal chalcogenide materials with a buckled structure like phosphorene, and has shown potential for applications in two-dimensional nanoelectronics devices. Although many methods to synthesize SnSe nanocrystals have been developed, a simple way to fabricate large-sized single-layer SnSe flakes remains a great challenge. Herein, we show the experimental method to directly grow large-sized single-layer rectangular SnSe flakes on commonly used SiO2/Si insulating substrates using a straightforward two-step fabrication method in an atmospheric pressure quartz tube furnace system. The single-layer rectangular SnSe flakes with an average thickness of ~6.8 &#197; and lateral dimensions of about 30 &#181;m &#215; 50 &#181;m were fabricated by a combination of vapor transport deposition technique and nitrogen etching route. We characterized the morphology, microstructure, and electrical properties of the rectangular SnSe flakes and obtained excellent crystallinity and good electronic properties. This article about the two-step fabrication method can help researchers grow other similar two-dimensional, large-sized, single-layer materials using an atmospheric pressure system.

A protocol is presented demonstrating a two-step fabrication technique to grow large-sized single-layer rectangular shaped SnSe flakes on low-cost SiO2/Si dielectrics wafers in an atmospheric pressure quartz tube furnace system.

Presión atmosférica fabricación de escamas de gran tamaño SnSe Rectangular de una sola capa

Tin selenide (SnSe) belongs to the family of layered metal chalcogenide materials with a buckled structure like phosphorene, and has shown potential for ...

Applicability Analysis of Assessment Methods for Morphological Parameters of Corroded Steel Bars

The irregular and uneven residual sections along the length of a corroded steel bar substantially change its mechanical properties and significantly dominate the safety and performance of an existing concrete structure. As a result, it is important to measure the geometry and amount of corrosion of a steel bar in a structure properly to assess the residual bearing capacity and service life of the structure. This paper introduces and compares five different methods for measuring the geometry and amount of corrosion of a steel bar. A single 500 mm long and 14 mm diameter steel bar is the specimen that is subjected to accelerated corrosion in this protocol. Its morphology and the amount of corrosion were carefully measured before and after using mass loss measurements, a Vernier caliper, drainage measurements, 3D scanning, and X-ray micro-computed tomography (XCT). The applicability and suitability of these different methods were then evaluated. The results show that the Vernier caliper is the best choice for measuring the morphology of a non-corroded bar, while 3D scanning is the most suitable for quantifying the morphology of a corroded bar.

This paper measures the geometry and the amount of corrosion of a steel bar using different methods: mass loss, calipers, drainage measurements, 3D scanning, and X-ray micro-computed tomography (XCT).

Análisis de la aplicabilidad de los métodos de evaluación de parámetros morfológicos de las barras de acero corroído

The irregular and uneven residual sections along the length of a corroded steel bar substantially change its mechanical properties and significantly ...

Using Flexible Gold-Titanium Reaction Cells to Simulate Pressure-Dependent Microbial Activity in the Context of Subsurface Biomining

Laboratory studies investigating subsurface microbial processes, such as metal leaching in deep ore deposits (biomining), share common and challenging obstacles, including the special environmental conditions that need to be replicated, e.g., high pressure and in some cases acidic solutions. The former requires an experimental setup suitable for pressurization up to 100 bar, while the latter demands a fluid container with high chemical resistance against corrosion and unwanted chemical reactions with the container wall. To meet these conditions for an application in the field of in situ biomining, a special flexible gold-titanium reaction cell inside a rocking high-pressure reactor was used in this study. The described system allowed simulation of in situ biomining through sulfur-driven microbial iron reduction in an anoxic, pressure-controlled, highly chemically inert experimental environment. The flexible gold-titanium reaction cell can accommodate up to 100 mL of sample solution, which can be sampled at any given time point while the system maintains the desired pressure. Experiments can be performed on timescales ranging from hours to months. Assembling the high-pressure reactor system is fairly time consuming. Nevertheless, when complex and challenging (microbiological) processes occurring in the earth&#39;s deep subsurface in chemically aggressive fluids have to be investigated in the laboratory, the advantages of this system outweigh the disadvantages. The results found that even at high pressure the microbial consortium is active, but at significantly lower metabolic rates.

This protocol describes microbial experiments under elevated pressures to study in situ biomining processes. The experimental approach employs a rocking high-pressure reactor equipped with a gold-titanium reaction cell containing a microbial culture in an acidic, iron-rich medium.

Uso de células flexibles de reacción de oro y titanio para simular la actividad microbiana dependiente de la presión en el contexto de la bioextracción subsuperficial

Laboratory studies investigating subsurface microbial processes, such as metal leaching in deep ore deposits (biomining), share common and challenging ...

Treating Surfaces with a Cold Atmospheric Pressure Plasma using the COST-Jet

In recent years, non-thermal atmospheric pressure plasmas have been used extensively for surface treatments, in particular, due to their potential in biological applications. However, the scientific results often suffer from reproducibility problems due to unreliable plasma conditions as well as complex treatment procedures. To address this issue and provide a stable and reproducible plasma source, the COST-Jet reference source was developed.
In this work, we propose a detailed protocol to perform reliable and reproducible surface treatments using the COST reference microplasma jet (COST-Jet). Common issues and pitfalls are discussed, as well as the peculiarities of the COST-Jet compared to other devices and its advantageous remote character. A detailed description of both solid and liquid surface treatment is provided. The described methods are versatile and can be adapted for other types of atmospheric pressure plasma devices.

This protocol is presented to characterize the setup, handling, and application of the COST-Jet for the treatment of diverse surfaces such as solids and liquids.

Tratamiento de superficies con un plasma de presión atmosférica fría utilizando el COST-Jet

In recent years, non-thermal atmospheric pressure plasmas have been used extensively for surface treatments, in particular, due to their potential in ...