Los autores agradecen al Sr. JO Hornkohl para el interés y el debate sobre el cálculo de los puntos fuertes de la línea molecular diatómicas. Este trabajo está apoyado en parte por el Centro de Aplicaciones Láser de la Universidad de Tennessee Space Institute.

1. Configuración del sistema óptico <ol><li> Coloque un divisor de haz a la salida del láser, permitiendo que la luz de longitud de onda 1.064 nm pase a través y para reflejar todos los demás radiaciones láser transitoria en un vertedero de haz. </li><li> Coloque un detector de fotodiodo PIN de alta velocidad para grabar una parte de la radiación láser reflejada por el divisor de haz. Conectar este detector al osciloscopio con cable coaxial para supervisar el pulso óptico con respecto a la activación por el generador de funciones y la ocurrencia de la conmutación Q en el Nd: YAG dispositivo. </li><li> Alinear tres espejos reflectantes de IR para posicionar el haz paralelo a la hendidura del espectrómetro. </li><li> Coloque una lente por encima de la etapa de traslación para enfocar el haz con el fin de generar óptica desglose de plasma paralelo a la hendidura del espectrómetro. Alinear dos lentes de cuarzo para el propósito de obtención de imágenes del plasma en la ranura. Las dos lentes de enfoque óptima coincide con el diseño del espectrómetro, es decir, el objetivo final tiene un apertura para realizar af # idéntica a la f # de elementos ópticos internos del espectrómetro. </li><li> Para mediciones por encima de 380 nm, la posición de un corte en el filtro entre las dos lentes con el propósito de bloquear la radiación por debajo de 380 nm. El corte en el filtro suprime las posibles contribuciones de UV (debido a la segunda orden de rejilla) a los espectros medidos. </li></ol> 2. Configuración de Adquisición de Datos <ol><li> Conectar un generador de funciones de forma de onda que proporciona una onda triangular a 50 Hz a una hecha a la medida circuito de división por cinco para obtener 10 Hz. El analizador óptico multicanal (OMA) se hace funcionar a 50 Hz y las lámparas de flash de láser de Nd: YAG se sincrónicamente funcionar a 10 Hz. Uno puede utilizar un ICCD en lugar de la OMA, que opera de forma síncrona a la tasa de la radiación de láser pulsado también. </li><li> Conecte una de las salidas del circuito a la medida de división por cinco a un generador de retardo digital. Utilice una salida para sincronizar el Nd: YAG lámparas de flash y otro de salida para control de los factores desencadenantes del intensificador de red de diodos lineal y un analizador óptico multicanal. Una vez más, en lugar de la matriz de diodos lineal intensificado y OMA se puede utilizar un ICCD. </li><li> Transmitir la salida de disparo ajustable del dispositivo láser a un osciloscopio y a un generador de impulsos. El osciloscopio se puede utilizar para controlar cuando la radiación de láser pulsado estará disponible para la generación de rotura óptica o ablación con láser. </li><li> Conectar la salida de alta tensión del generador de impulsos digital a la matriz de diodos lineal intensificado. </li><li> Conectar la otra salida del generador de impulsos para el osciloscopio. </li><li> Conecte la salida de red de diodos lineal intensificado a la OMA. </li></ol> 3. Sincronización y Medición <ol><li> Ajuste el generador de funciones de forma de onda a la salida de un pulso triangular que funciona a 50 ± 1 Hz. Este generador de funciones proporciona la frecuencia maestra. Un hecho a la medida del circuito de división por cinco y un generador de retardo digital se utilizan para accomisariar sincronización. </li><li> Inicie el sistema de enfriamiento de agua y fuente de alimentación para el dispositivo láser. Activar láser. </li><li> Determinar el tiempo para la radiación láser para viajar desde la abertura de salida del láser Nd: YAG a la zona en frente de la hendidura espectrómetro como sigue: Medir la distancia de la trayectoria de la luz y calcular el tiempo de tránsito utilizando la velocidad de la luz. Cuenta para este tiempo de tránsito en el establecimiento del tiempo de retardo de puerta en el siguiente paso. </li><li> En el generador de impulsos digitales, establezca la anchura de la puerta para la medición y el tiempo de retardo de la descomposición óptica o la ablación con láser de pulso, y usar el osciloscopio para monitorear el tiempo de retardo. El tiempo de retardo se determinará cuánto tiempo se debe esperar para la recopilación de datos después de producirse una avería. La anchura de la puerta determina el tiempo que la matriz de diodos está expuesto a la radiación de plasma. </li><li> Generar rotura óptica en el aire y / o colocar una muestra en la etapa de traslación de tal forma que se producirá la ablación. Imagen de la microplasma en la ranura espectrómetro. </li><li> Comience mediciones y datos de registro con la matriz intensificado lineal de diodos y un analizador óptico multicanal (o con un ICCD). </li></ol> 4. Calibración de longitud de onda <ol><li> Espectros Registro de las lámparas estándar de calibración: neón, mercurio y lámparas de hidrógeno. Utilice el dispositivo experimental con lámparas de poner en el lugar donde se generó plasma. </li><li> El uso de las longitudes de onda conocidas de las lámparas, realizar un ajuste lineal o cúbica para obtener la correspondencia de píxeles de longitud de onda. El propósito de una calibración precisa es para corregir las no linealidades que se asocian generalmente con la medición de los espectros. </li><li> Repita calibraciones para H, C 2, CN, y TiO regiones espectrales de interés. </li></ol> 5. Calibración Intensidad <ol><li> Encienda una lámpara de tungsteno de calibración y esperar a que se caliente. </li><li> Utilice un pirómetro óptico para medir la temperatura de la lámpara activo. </li><li> Utilice el dispositivo experimental para rEcord el espectro de la lámpara activo. </li><li> Calcular una curva de cuerpo negro a partir de la ley de radiación de Plank usando la temperatura medida como parámetro de entrada. </li><li> Ajustar la curva calculada con el espectro de la lámpara activo. Determinar los factores por los cuales las intensidades registradas de la curva calculada. Aplique esos factores para corregir espectros registrados para la longitud de onda dependiente sensibilidad del detector. </li><li> Repita esto para cada región se utilizó el espectrómetro. </li></ol> 6. Transferencia de datos <ol><li> Para preparar el medio para la transferencia de archivos. </li><li> Para cada medición de datos, grabar en el medio. </li><li> Tome este medio y cargar los archivos en él a un equipo de trabajo. </li></ol> 7. Preparación de Archivos <ol><li> Para cada archivo, lo revisará en secciones, una que contiene datos grabados, y los demás que especifican la longitud de onda de arranque y cambio de media longitud de onda por punto de datos. </li><li> Utilice estas secciones para crear un nuevo archivo para que coincidalongitudes de onda con los datos registrados. </li></ol> 8. Análisis molecular diatómico <ol><li> Seleccione el archivo de la longitud de onda y el archivo de la fuerza de línea correspondiente. </li><li> Seleccionar el desplazamiento de la línea de base. <ol><li> Establecer si el desplazamiento es constante, lineal o cuadrática. </li><li> Establecer los coeficientes correspondientes a valores fijos o variables. </li></ol></li><li> Ajuste la resolución y la temperatura, los cuales pueden ser fijos o variada. </li><li> Establecer la tolerancia de ajuste para los espectros sintética para estar en forma para los espectros medidos. </li><li> Montar la calculada para los espectros experimentales utilizando un algoritmo Nelder-Mead. </li><li> El uso de los mejores parámetros de ajuste de los espectros calculado para cada medición, inferir los parámetros de microplasma observados en los diferentes retardos de tiempo y anchos de puerta utilizadas. </li></ol>

<ol>
	<li>Miziolek, A. W., Palleschi, V., Schechter, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Laser Induced Breakdown Spectroscopy. , (2006).</li><li>Cremers, D. E., Radziemski, L. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Handbook of laser-induced Breakdown Spectroscopy. , (2006).</li><li>Singh, J. P., Thakur, S. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Laser Induced Breakdown Spectroscopy. , (2007).</li><li>Hahn, D. W., Omenetto, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Laser-induced+breakdown+spectroscopy+(LIBS),+Part+I:+review+of+basic+diagnostics+and+plasma-particle+iterations:+still-challenging+issues+within+the+analytical+plasma+community.">Laser-induced breakdown spectroscopy (LIBS), Part I: review of basic diagnostics and plasma-particle iterations: still-challenging issues within the analytical plasma community.</a> Appl. Spectrosc. 64, (2010).</li><li>Hahn, D. W., Omenetto, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Laser-induced+breakdown+spectroscopy+(LIBS),+Part+II:+review+of+instrumental+and+methodological+approaches+to+material+analysis+and+applications+to+different+fields.">Laser-induced breakdown spectroscopy (LIBS), Part II: review of instrumental and methodological approaches to material analysis and applications to different fields.</a> Appl. Spectrosc. 66, 347 (2012).</li><li>Parigger, C. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Atomic+and+molecular+emissions+in+laser-induced+breakdown+spectroscopy.">Atomic and molecular emissions in laser-induced breakdown spectroscopy.</a> Spectrochim. Acta Part B. 79, 4-16 (2013).</li><li>Konjevi&#263;, N., Lesage, A., Fuhr, J. R., Wiese, W. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Experimental+Stark+widths+and+shifts+for+spectral+lines+of+neutral+and+ionized+atoms.">Experimental Stark widths and shifts for spectral lines of neutral and ionized atoms.</a> J. Phys. Chem. Ref. Data. 31, 819-927 (2002).</li><li>Oks, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stark+broadening+of+hydrogen+and+hydrogen-like+spectral+lines+in+plasmas:+the+physical+insight.">Stark broadening of hydrogen and hydrogen-like spectral lines in plasmas: the physical insight.</a> Alpha Science Int. , (2006).</li><li>Parigger, C. G., Dackman, M., Hornkohl, J. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Time-resolved+spectroscopy+measurements+of+hydrogen-alpha,+-beta,+and+-gamma+emissions.">Time-resolved spectroscopy measurements of hydrogen-alpha, -beta, and -gamma emissions.</a> Appl. Opt. 47, (2008).</li><li>Parigger, C. G., Oks, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hydrogen+Balmer+series+spectroscopy+in+laser-induced+breakdown+plasmas.">Hydrogen Balmer series spectroscopy in laser-induced breakdown plasmas.</a> Int. Rev. Atom. Mol. Phys. 1, 13-23 (2010).</li><li>Lucena, A. D., Tobaria, L. M., Laserna, J. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=New+challenges+and+insights+in+the+detection+and+spectral+identification+of+organic+explosives+by+laser+induced+breakdown+spectroscopy.">New challenges and insights in the detection and spectral identification of organic explosives by laser induced breakdown spectroscopy.</a> Spectrochim. Acta Part B. 66 (1), 12-20 (2011).</li><li>Swafford, L. D., Parigger, C. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Measurement+of+hydrogen+Balmer+Series+lines+following+laser-induced+optical+breakdown+in+laboratory+air.">Measurement of hydrogen Balmer Series lines following laser-induced optical breakdown in laboratory air.</a> Accepted, Int. Rev. Atom. Mol. Phys. 4 (1), (2013).</li><li>Hornkohl, J. O., Nemes, L., Parigger, C. G., Nemes, L., Irle, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spectroscopy+of+Carbon+Containing+Diatomic+Molecules.">Spectroscopy of Carbon Containing Diatomic Molecules.</a> Spectroscopy, Dynamics and Molecular Theory of Carbon Plasmas and Vapor. , 113-165 (2011).</li><li>Parigger, C., Hornkohl, J. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diatomic+molecular+spectroscopy+with+standard+and+anomalous+commutators.">Diatomic molecular spectroscopy with standard and anomalous commutators.</a> Int. Rev. Atom. Mol. Phys. 1, 25-43 (2010).</li><li>Parigger, C. G., Hornkohl, J. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Computation+of+AlO+emission+spectra.">Computation of AlO emission spectra.</a> Spectrochim. Acta Part A. 81, 404-411 (2011).</li><li>Hermann, J., Peronne, A., Dutouquet, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Analysis+of+the+TiO-&#947;+System+for+temperature+measurements+in+laser-induced+plasma.">Analysis of the TiO-&#947; System for temperature measurements in laser-induced plasma.</a> J. Phys. B: At. Mol. Opt. Phys. 34, 153-164 (2001).</li><li>Woods, A. C., Parigger, C. G., Hornkohl, J. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Measurements+and+analysis+of+titanium+monoxide+spectra+in+laser-induced+plasma.">Measurements and analysis of titanium monoxide spectra in laser-induced plasma.</a> Opt. Lett. 37, 5139-5141 (2012).</li><li>Witte, M. J., Parigger, C. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Measurement+and+analysis+of+carbon+Swan+spectra+following+laser-induced+optical+breakdown+in+air.">Measurement and analysis of carbon Swan spectra following laser-induced optical breakdown in air.</a> Accepted, Int. Rev. Atom. Mol. Phys. 4 (1), (2013).</li><li>Surmick, D. M., Parigger, C. G., Woods, A. C., Donaldson, A. B., Height, J. L., Gill, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Analysis+of+emission+Spectra+of+Aluminum+Monoxide+in+a+Solid+Propellant+Flame.">Analysis of emission Spectra of Aluminum Monoxide in a Solid Propellant Flame.</a> Int. Rev. Atom. Mol. Phys. 3 (2), 2-137 (2012).</li><li>Woods, A. C., Parigger, C. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Time-resolved+Temperature+Inferences+Utilizing+the+TiO+A3&#966;&#8594;X3&#916;+Band+in+Laser-induced+Plasma.">Time-resolved Temperature Inferences Utilizing the TiO A3&#966;&#8594;X3&#916; Band in Laser-induced Plasma.</a> Int. Rev. Atom. Mol. Phys. 3 (2), 103-111 (2012).</li></ol>

Todos los autores declaran que no tienen intereses financieros en competencia.

La resolución temporal protocolo de medición y resultados representativos se discuten más aquí. Es importante sincronizar los pulsos de láser, generados a una tasa de 10 Hz, con la frecuencia de funcionamiento de 50 Hz de la matriz intensificado lineal de diodo y OMA (o ICCD). Además, la sincronización exacta de pulsos de láser y la apertura de la puerta de la matriz intensificado lineal de diodo (o alternativamente ICCD) es esencial. El generador de ondas, se indica en el esquema experimental, se utiliza para s...

Espectroscopia de ruptura inducida por láser (LIBS) Técnicas de 1-5 tienen aplicaciones en 6-12 atómica y estudios moleculares de plasma 13-20 generada con radiación láser. Espectroscopia resuelta en el tiempo es esencial para la determinación de las características transitorias del plasma. La temperatura y la densidad de electrones, por nombrar sólo dos parámetros del plasma, se pueden medir proporcionado un modelo teórico razonable de la descomposición de plasma está disponible. La separación de la radiación de electrones libres de emisiones atómicas y moleculares nos permite explorar con precisión los fenómenos transitorios. Al centrarse en una ventana temporal específica, se puede &quot;congelar&quot; la decadencia de plasma y así obtener huellas espectroscópicas precisos. LIBS tiene una variedad de aplicaciones y, recientemente, el interés en LIBS-diagnóstico muestra un aumento considerable cuando se mide por el número de investigadores que publican en el campo. Pico-y femtosegundos generada microplasma es de cursointerés de la investigación, sin embargo, los arreglos experimentales históricamente LIBS utiliza radiación láser de nanosegundos. La figura 1 muestra un dispositivo experimental típico para la espectroscopia descomposición inducida por láser. Para este protocolo, la energía desglose funcional para el haz inicial es del orden de 75 mJ pulso, en la longitud de onda infrarroja de 1064 nm. Esta energía de pulso se puede ajustar según sea necesario. . El plasma se dispersa por el espectrómetro y se mide con un array lineal de diodo intensificado y OMA o, alternativamente, reflejado en un 2-dimensional dispositivo de carga acoplada intensificada (ICCD) La Figura 2 ilustra el diagrama de temporización para los experimentos de tiempo-resuelto: la sincronización de pulsos radiación láser con lectura, disparador de pulsos láser, fuego láser, y el retardo de puerta abierta. Espectroscopía con resolución temporal exitosa requiere varios procedimientos de calibración. Estos procedimientos incluyen la calibración de longitud de onda, de vueltacorrección de suelo, y lo más importante, la corrección de la sensibilidad del detector. Sensibilidad datos corregidos son importantes para la comparación de espectros medidos y modelados. Para un aumento de la relación señal a ruido, se registran múltiples eventos de degradación inducida por láser.

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			<td height="80" style="height:80px;width:216px;">Custom Box</td>
			<td style="width:71px;">UTSI</td>
			<td style="width:119px;">None</td>
			<td style="width:167px;">Signal divider and conditioner. An oscilloscope can be used in place of this</td>
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			<td height="20" style="height:20px;width:216px;"></td>
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			<td height="80" style="height:80px;width:216px;">Four Channel Digital Delay/Pulse Generator</td>
			<td style="width:71px;">Stanford Research Systems, Inc.</td>
			<td style="width:119px;">Model DG535</td>
			<td style="width:167px;">Companies: Tequipment, diyAudio</td>
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			<td height="100" style="height:100px;width:216px;">Four Channel Color Digital Phosphor Oscilloscope</td>
			<td style="width:71px;">Tektronix</td>
			<td style="width:119px;">TDS 3054</td>
			<td style="width:167px;">500 MHz - 5 GS/sec, Companies: Amazon, Tektronix, Fluke, Agilent Technologies, Pico Technology</td>
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			<td height="60" style="height:60px;width:216px;">Wavetek FG3C Function Generator</td>
			<td style="width:71px;">Wavetek</td>
			<td style="width:119px;">FG3C</td>
			<td style="width:167px;">Companies: Tequipment, Stanford Research Systems, BK Precision</td>
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			<td height="100" style="height:100px;width:216px;">Nd:YAG Laser</td>
			<td style="width:71px;">Quanta-Ray</td>
			<td style="width:119px;">DCR-2A(10) PS</td>
			<td style="width:167px;">Laser radiation, Class IV.&#160; Companies: Lambda Photometrics, Continuum, Ellipse, Newport</td>
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			<td height="80" style="height:80px;width:216px;">Si Biased Detector</td>
			<td style="width:71px;">Thorlabs</td>
			<td style="width:119px;">DET10A/M</td>
			<td style="width:167px;">200-1,100 nm, with ND10A reflective filter. Companies: Canberra, Edmund Optics</td>
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			<td style="width:71px;">Thorlabs</td>
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			<td style="width:167px;">Companies: Edmund Optics, Newport</td>
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			<td height="60" style="height:60px;width:216px;">2 in Fused Silica Plano-Convex lens, uncoated</td>
			<td style="width:71px;">Newport</td>
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			<td style="width:167px;">Convex lens, f/4.&#160; Companies: Edmund Optics, Thorlabs</td>
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			<td height="20" style="height:20px;width:216px;"></td>
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		</tr>
		<tr height="100">
			<td height="100" style="height:100px;width:216px;">Spectrograph</td>
			<td style="width:71px;">Instruments S.A. division Jobin-Yvon</td>
			<td style="width:119px;">HR 640</td>
			<td style="width:167px;">Companies: Andor, Newport, Horiba</td>
		</tr>
		<tr height="100">
			<td height="100" style="height:100px;width:216px;">Manual and electronic controller for Spectrograph</td>
			<td style="width:71px;">Instruments S.A. division Jobin-Yvon</td>
			<td style="width:119px;">Model 980028</td>
			<td style="width:167px;">Manual and electronic controller for Spectrograph</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Mega 4000</td>
			<td style="width:71px;">Mega</td>
			<td style="width:119px;">Model 129709</td>
			<td style="width:167px;">Computer interface for Spectrograph</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Gateway 2000 Crystal Scan 1024 monitor</td>
			<td style="width:71px;">Gateway</td>
			<td style="width:119px;">PMV14AC</td>
			<td style="width:167px;">Monitor for computer interface</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:216px;"></td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="80">
			<td height="80" style="height:80px;width:216px;">20 MHz Oscilloscope</td>
			<td style="width:71px;">BK Precision</td>
			<td style="width:119px;">Model 2125</td>
			<td style="width:167px;">Companies: Amazon, Tektronix, Fluke, Agilent Technologies, Pico Technology</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:216px;"></td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="100">
			<td height="100" style="height:100px;width:216px;">6040 Universal Pulse Generator</td>
			<td style="width:71px;">Berkeley Nucleonics Corporation</td>
			<td style="width:119px;">Model 6040</td>
			<td style="width:167px;">Companies: Agilent Technologies, Tektronix, Quantum Composers</td>
		</tr>
		<tr height="100">
			<td height="100" style="height:100px;width:216px;">Separate component to 6040 Universal Pulse Generator</td>
			<td style="width:71px;">Berkeley Nucleonics Corporation</td>
			<td style="width:119px;">Model 202 H</td>
			<td style="width:167px;">Separate component to 6040 Universal Pulse Generator</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:216px;"></td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="80">
			<td height="80" style="height:80px;width:216px;">ICCD Camera</td>
			<td style="width:71px;">EG&#38;G Parc</td>
			<td style="width:119px;">Model 46113</td>
			<td style="width:167px;">Companies: Andor, Standford Computer Optics, LaVision, Hamamatsu</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;width:216px;"></td>
			<td style="width:71px;"></td>
			<td style="width:119px;"></td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="100">
			<td height="100" style="height:100px;width:216px;">OMA III</td>
			<td style="width:71px;">EG&#38;G Parc</td>
			<td style="width:119px;">Model 1460</td>
			<td style="width:167px;">Spectral data acquisition and analysis. Unit discontinued, replaced by software installed on computers.</td>
		</tr>
	</tbody>
</table>

measurement and analysis of atomic hydrogen and diatomic molecular alo, c2, cn, and tio spectra following laser-induced optical breakdown

En este trabajo, presentamos las mediciones con resolución temporal de los espectros atómicos y diatómico siguientes rotura óptica inducida por láser. Se utiliza un arreglo típico LIBS. Aquí operamos un láser de Nd: YAG a una frecuencia de 10 Hz a la longitud de onda fundamental de 1064 nm. Los 14 ns pulsos con anenergy de 190 mJ / pulso están enfocados a un tamaño de 50 micras lugar para generar un plasma de rotura óptica o ablación con láser en el aire. El microplasma se forma la imagen sobre la rendija de entrada de un espectrómetro de 0.6 m, y los espectros se registran usando un 1,800 surcos / mm rejilla de una matriz de diodos lineal intensificado y analizador óptico multicanal (OMA) o un ICCD. De interés son las líneas atómicas ampliado-Stark de la serie de Balmer de hidrógeno para inferir la densidad de electrones. También en detalles sobre las mediciones de temperatura de los espectros de emisión diatómica de monóxido de aluminio (ALO), carbono (C 2), de cianógeno (CN), y monóxido de titanio (TiO $). Los procedimientos experimentales incluyen wavelength y calibraciones de sensibilidad. Análisis de los espectros molecular grabado se lleva a cabo por el ajuste de los datos con resistencias a la línea tabulados. Por otra parte, las simulaciones de tipo Monte-Carlo se realizan para estimar los márgenes de error. Mediciones Tiempo de resolver son esenciales para el plasma transitoria comúnmente encontrado en LIBS.

LIBS utiliza la radiación de láser pulsado para ionizar suficientemente una muestra para formar el plasma. Desglose inducida por láser de sustancias gaseosas creará de plasma que está centrado sobre la región focal del haz de excitación, mientras que la ablación con láser en superficies sólidas producirá de plasma sobre la superficie de la muestra. El plasma se genera por enfocar la radiación óptica en el orden de 100 GW / cm 2 de pulsos de nanosegundos de degradación. Para producir la ablación...

Watch this Scientific Journal Video about Measurement and Analysis of Atomic Hydrogen and Diatomic Molecular AlO, C2, CN, and TiO Spectra Following Laser-induced Optical Breakdown at JoVE.com

Measurement and Analysis of Atomic Hydrogen and Diatomic Molecular AlO, C2, CN, and TiO Spectra Following Laser-induced Optical Breakdown

Especies moleculares atómicas y diatómicas Tiempo de resolver se miden usando LIBS. Los espectros se recogieron en varios retardos de tiempo después de la generación de plasma de rotura óptica con Nd: la radiación láser YAG y se analizan para inferir la densidad electrónica y la temperatura.

Medición y Análisis de hidrógeno atómico y molecular diatómico AlO, C<sub&gt; 2</sub&gt;, CN, y el TiO Spectra siguiente desglose óptica inducida por láser

In this work, we present time-resolved measurements of atomic and diatomic spectra following laser-induced optical breakdown. A typical LIBS arrangement ...

measurement-analysis-atomic-hydrogen-diatomic-molecular-alo-c2-cn-tio

Research

JoVE Journal

Engineering

Measurement and Analysis of Atomic Hydrogen and Diatomic Molecular AlO, C2, CN, and TiO Spectra Following Laser-induced Optical Breakdown

14.1K vistas.  University of Tennessee Space Institute.  Especies moleculares atómicas y diatómicas Tiempo de resolver se miden usando LIBS. Los espectros se recogieron en varios retardos de tiempo después de la generación de plasma de rotura óptica con Nd: la radiación láser YAG y se analizan para inferir la densidad electrónica y la temperatura. 

Video: Measurement and Analysis of Atomic Hydrogen and Diatomic Molecular AlO, C2, CN, and TiO Spectra Following Laser-induced Optical Breakdown

Construction and Testing of Coin Cells of Lithium Ion Batteries

Rechargeable lithium ion batteries have wide applications in electronics, where customers always demand more capacity and longer lifetime. Lithium ion batteries have also been considered to be used in electric and hybrid vehicles1 or even electrical grid stabilization systems2. All these applications simulate a dramatic increase in the research and development of battery materials3-7, including new materials3,8, doping9, nanostructuring10-13, coatings or surface modifications14-17 and novel binders18. Consequently, an increasing number of physicists, chemists and materials scientists have recently ventured into this area. Coin cells are widely used in research laboratories to test new battery materials; even for the research and development that target large-scale and high-power applications, small coin cells are often used to test the capacities and rate capabilities of new materials in the initial stage. 
 In 2010, we started a National Science Foundation (NSF) sponsored research project to investigate the surface adsorption and disordering in battery materials (grant no. DMR-1006515). In the initial stage of this project, we have struggled to learn the techniques of assembling and testing coin cells, which cannot be achieved without numerous help of other researchers in other universities (through frequent calls, email exchanges and two site visits). Thus, we feel that it is beneficial to document, by both text and video, a protocol of assembling and testing a coin cell, which will help other new researchers in this field. This effort represents the "Broader Impact" activities of our NSF project, and it will also help to educate and inspire students.
In this video article, we document a protocol to assemble a CR2032 coin cell with a LiCoO2 working electrode, a Li counter electrode, and (the mostly commonly used) polyvinylidene fluoride (PVDF) binder. To ensure new learners to readily repeat the protocol, we keep the protocol as specific and explicit as we can. However, it is important to note that in specific research and development work, many parameters adopted here can be varied. First, one can make coin cells of different sizes and test the working electrode against a counter electrode other than Li. Second, the amounts of C black and binder added into the working electrodes are often varied to suit the particular purpose of research; for example, large amounts of C black or even inert powder were added to the working electrode to test the "intrinsic" performance of cathode materials14. Third, better binders (other than PVDF) have also developed and used18. Finally, other types of electrolytes (instead of LiPF6) can also be used; in fact, certain high-voltage electrode materials will require the uses of special electrolytes7.

A protocol to construct and test coin cells of lithium ion batteries is described. The specific procedures of making a working electrode, preparing a counter electrode, assembling a cell inside a glovebox and testing the cell are presented.

Construcción y verificación de las células de la moneda de baterías de ion de litio

Rechargeable lithium ion batteries have wide applications in electronics, where customers always demand more capacity and longer lifetime.  Lithium ion ...

Investigación

Ingeniería

Laser-induced Breakdown Spectroscopy: A New Approach for Nanoparticle's Mapping and Quantification in Organ Tissue

Emission spectroscopy of laser-induced plasma was applied to elemental analysis of biological samples. Laser-induced breakdown spectroscopy (LIBS) performed on thin sections of rodent tissues: kidneys and tumor, allows the detection of inorganic elements such as (i) Na, Ca, Cu, Mg, P, and Fe, naturally present in the body and (ii) Si and Gd, detected after the injection of gadolinium-based nanoparticles. The animals were euthanized 1&#160;to 24 hr&#160;after intravenous injection of particles. A two-dimensional scan of the sample, performed using a motorized micrometric 3D-stage, allowed the infrared laser beam exploring the surface with a lateral resolution less than 100 &#956;m. Quantitative chemical images of Gd element inside the organ were obtained with sub-mM sensitivity. LIBS offers a simple and robust method to study the distribution of inorganic materials without any specific labeling. Moreover, the compatibility of the setup with standard optical microscopy emphasizes its potential to provide multiple images of the same biological tissue with different types of response:&#160;elemental, molecular, or cellular.

Laser-induced Breakdown Spectroscopy: A New Approach for Nanoparticle&#039;s Mapping and Quantification in Organ Tissue

Laser-induced breakdown spectroscopy performed on thin organ and tumor tissue successfully detected natural elements and artificially injected gadolinium (Gd), issued from Gd-based nanoparticles. Images of chemical elements reached a resolution of 100 &#956;m and quantitative sub-mM sensitivity. The compatibility of the setup with standard optical microscopy emphasizes its potential to provide multiple images of a same biological tissue.

Inducida por láser Breakdown Spectroscopy: un nuevo enfoque para el mapeo y cuantificación de nanopartículas en tejidos de órganos

Emission spectroscopy of laser-induced plasma was applied to elemental analysis of biological samples. Laser-induced breakdown spectroscopy (LIBS) ...

Quantification of Hydrogen Concentrations in Surface and Interface Layers and Bulk Materials through Depth Profiling with Nuclear Reaction Analysis

Nuclear reaction analysis (NRA) via the resonant 1H(15N,&#945;&#947;)12C reaction is a highly effective method of depth profiling that quantitatively and non-destructively reveals the hydrogen density distribution at surfaces, at interfaces, and in the volume of solid materials with high depth resolution. The technique applies a 15N ion beam of 6.385 MeV provided by an electrostatic accelerator and specifically detects the 1H isotope in depths up to about 2 &#956;m from the target surface. Surface H coverages are measured with a sensitivity in the order of ~1013 cm-2 (~1% of a typical atomic monolayer density) and H volume concentrations with a detection limit of ~1018 cm-3 (~100 at. ppm). The near-surface depth resolution is 2-5 nm for surface-normal 15N ion incidence onto the target and can be enhanced to values below 1 nm for very flat targets by adopting a surface-grazing incidence geometry. The method is versatile and readily applied to any high vacuum compatible homogeneous material with a smooth surface (no pores). Electrically conductive targets usually tolerate the ion beam irradiation with negligible degradation. Hydrogen quantitation and correct depth analysis require knowledge of the elementary composition (besides hydrogen) and mass density of the target material. Especially in combination with ultra-high vacuum methods for in-situ target preparation and characterization, 1H(15N,&#945;&#947;)12C NRA is ideally suited for hydrogen analysis at atomically controlled surfaces and nanostructured interfaces. We exemplarily demonstrate here the application of 15N NRA at the MALT Tandem accelerator facility of the University of Tokyo to (1) quantitatively measure the surface coverage and the bulk concentration of hydrogen in the near-surface region of a H2 exposed Pd(110) single crystal, and (2) to determine the depth location and layer density of hydrogen near the interfaces of thin SiO2 films on Si(100).

We illustrate the application of 1H(15N,&#945;&#947;)12C resonant nuclear reaction analysis (NRA) to quantitatively evaluate the density of hydrogen atoms on the surface, in the volume, and at an interfacial layer of solid materials. The near-surface hydrogen depth profiling of a Pd(110) single crystal and of SiO2/Si(100) stacks is described.

La cuantificación de las concentraciones de hidrógeno en superficies e interfaces de capas y materiales a granel a través de perfiles de profundidad con el análisis de Reacción nuclear

Nuclear reaction analysis (NRA) via the resonant 1H(15N,&#945;&#947;)12C reaction is a highly effective method of depth profiling that quantitatively and ...

Laser-induced Forward Transfer of Ag Nanopaste

Over the past decade, there has been much development of non-lithographic methods1-3 for printing metallic inks or other functional materials. Many of these processes such as inkjet3 and laser-induced forward transfer (LIFT)4 have become increasingly popular as interest in printable electronics and maskless patterning has grown. These additive manufacturing processes are inexpensive, environmentally friendly, and well suited for rapid prototyping, when compared to more traditional semiconductor processing techniques. While most direct-write processes are confined to two-dimensional structures and cannot handle materials with high viscosity (particularly inkjet), LIFT can transcend both constraints if performed properly. Congruent transfer of three dimensional pixels (called voxels), also referred to as laser decal transfer (LDT)5-9, has recently been demonstrated with the LIFT technique using highly viscous Ag nanopastes to fabricate freestanding interconnects, complex voxel shapes, and high-aspect-ratio structures. In this paper, we demonstrate a simple yet versatile process for fabricating a variety of micro- and macroscale Ag structures. Structures include simple shapes for patterning electrical contacts, bridging and cantilever structures, high-aspect-ratio structures, and single-shot, large area transfers using a commercial digital micromirror device (DMD) chip.

We demonstrate the use of the Laser-induced forward transfer technique (LIFT) for the printing of high-viscosity Ag paste. This technique offers a simple, low temperature, robust process for non-lithographically printing microscale 2D and 3D structures.

Transferencia Forward inducida por láser de Ag nanopasta

Over the past decade, there has been much development of non-lithographic methods1-3 for printing metallic inks or other functional materials. Many of ...

Optical Trap Loading of Dielectric Microparticles In Air

We demonstrate a method to trap a selected dielectric microparticle in air using radiation pressure from a single-beam gradient optical trap. Randomly scattered dielectric microparticles adhered to a glass substrate are momentarily detached using ultrasonic vibrations generated by a piezoelectric transducer (PZT). Then, the optical beam focused on a selected particle lifts it up to the optical trap while the vibrationally excited microparticles fall back to the substrate. A particle may be trapped at the nominal focus of the trapping beam or at a position above the focus (referred to here as the levitation position) where gravity provides the restoring force. After the measurement, the trapped particle can be placed at a desired position on the substrate in a controlled manner. 
In this protocol, an experimental procedure for selective optical trap loading in air is outlined. First, the experimental setup is briefly introduced. Second, the design and fabrication of a PZT holder and a sample enclosure are illustrated in detail. The optical trap loading of a selected microparticle is then demonstrated with step-by-step instructions including sample preparation, launching into the trap, and use of electrostatic force to excite particle motion in the trap and measure charge. Finally, we present recorded particle trajectories of Brownian and ballistic motions of a trapped microparticle in air. These trajectories can be used to measure stiffness or to verify optical alignment through time domain and frequency domain analysis. Selective trap loading enables optical tweezers to track a particle and its changes over repeated trap loadings in a reversible manner, thereby enabling studies of particle-surface interaction.

A protocol for launching and stably trapping selected dielectric microparticles in air is presented.

Cargando óptica Trampa de micropartículas en dieléctrica del aire

We demonstrate a method to trap a selected dielectric microparticle in air using radiation pressure from a single-beam gradient optical trap. Randomly ...

In Situ High Pressure Hydrogen Tribological Testing of Common Polymer Materials Used in the Hydrogen Delivery Infrastructure

High pressure hydrogen gas is known to adversely affect metallic components of compressors, valves, hoses, and actuators. However, relatively little is known about the effects of high pressure hydrogen on the polymer sealing and barrier materials also found within these components. More study is required in order to determine the compatibility of common polymer materials found in the components of the hydrogen fuel delivery infrastructure with high pressure hydrogen. As a result, it is important to consider the changes in physical properties such as friction and wear in situ while the polymer is exposed to high pressure hydrogen. In this protocol, we present a method for testing the friction and wear properties of ethylene propylene diene monomer (EPDM) elastomer samples in a 28 MPa high pressure hydrogen environment using a custom-built in situ pin-on-flat linear reciprocating tribometer. Representative results from this testing are presented which indicate that the coefficient of friction between the EPDM sample coupon and steel counter surface is increased in high pressure hydrogen as compared to the coefficient of friction similarly measured in ambient air.

In Situ High Pressure Hydrogen Tribological Testing of Common Polymer Materials Used in the Hydrogen Delivery Infrastructure

A test methodology for quantifying tribological properties of polymers used in hydrogen infrastructure service is demonstrated and characteristic results for a common elastomer are discussed.

In Situ Tribológicas de polímeros comunes utilizados en la infraestructura de suministro de hidrógeno de hidrógeno de alta presión

High pressure hydrogen gas is known to adversely affect metallic components of compressors, valves, hoses, and actuators. However, relatively little is ...

Atomic Layer Deposition of Vanadium Dioxide and a Temperature-dependent Optical Model

Vanadium dioxide is a material that has a reversible metal-insulator phase change near 68 &#176;C. To grow VO2 on a wide variety of substrates, with wafer-scale uniformity and angstrom level control of thickness, the method of atomic-layer deposition was chosen. This ALD process enables high-quality, low-temperature (&#8804;150 &#176;C) growth of ultrathin films (100-1000 &#197;) of VO2. For this demonstration, the VO2 films were grown on sapphire substrates. This low temperature growth technique produces mostly amorphous VO2 films. A subsequent anneal in an ultra-high vacuum chamber with a pressure of 7x10-4 Pa of ultra-high purity (99.999%) oxygen produced oriented, polycrystalline VO2 films. The crystallinity, phase, and strain of the VO2 were determined by Raman spectroscopy and X-ray diffraction, while the stoichiometry and impurity levels were determined by X-ray photoelectron spectroscopy, and finally the morphology was determined by atomic force microscopy. These data demonstrate the high-quality of the films grown by this technique. A model was created to fit to the data for VO2 in its metallic and insulating phases in the near infrared spectral region. The permittivity and refractive index of the ALD VO2 agreed well with the other fabrication methods in its insulating phase, but showed a difference in its metallic state. Finally, the analysis of the films&#39; optical properties enabled the creation of a wavelength- and temperature-dependent model of the complex optical refractive index for developing VO2 as a tunable refractive index material.

Thin films (100-1000 &#197;) of vanadium dioxide (VO2) were created by atomic-layer deposition (ALD) on sapphire substrates. Following this, the optical properties were characterized through the metal-insulator transition of VO2. From the measured optical properties, a model was created to describe the tunable refractive index of VO2.

Deposición de capa atómica de dióxido de vanadio y un modelo óptico dependiente de la temperatura

Vanadium dioxide is a material that has a reversible metal-insulator phase change near 68 &#176;C. To grow VO2 on a wide variety of substrates, with ...

Quantitative Analysis of Vacuum Induction Melting by Laser-induced Breakdown Spectroscopy

Vacuum induction melting is a popular method for refining high purity metal and alloys. Traditionally, standard process control in metallurgy involves several steps, include drawing samples, cooling, cutting, transport to the laboratory, and analysis. The whole analysis process requires more than 30 minutes, which hinders on-line process control. Laser-induced breakdown spectroscopy is an excellent on-line analysis method that can satisfy the requirements of vacuum induction melting because it is fast and noncontact and does not require sample preparation. The experimental facility uses a lamp-pumped Q-switched laser to ablate melted liquid steel with an output energy of 80 mJ, a frequency of 5 Hz, a FWHM pulse width of 20 ns, and a working wavelength of 1,064 nm. A multi-channel linear charge coupled device (CCD) spectrometer is used to measure the emission spectrum in real time, with a spectral range from 190 to 600 nm and a resolution of 0.06 nm at a wavelength of 200 nm. The protocol includes several steps: standard alloy sample preparation and an ingredient test, smelting of standard samples and determination of the laser breakdown spectrum, and construction of the elements concentration quantitative analysis curve of each element. To realize the concentration analysis of unknown samples, the spectrum of a sample also needs to be measured and disposed with the same process. The composition of all main elements in the melted alloy can be quantitatively analyzed with an internal standard method. The calibration curve shows that the limit of detection of most metal elements ranges from 20-250 ppm. The concentration of elements, such as Ti, Mo, Nb, V, and Cu, can be lower than 100 ppm, and the concentrations of Cr, Al, Co, Fe, Mn, C, and Si range from 100-200 ppm. The R2 of some calibration curves can exceed 0.94.

During vacuum induction melting, laser-induced breakdown spectroscopy is used to perform real-time quantitative analysis of the main-ingredient elements of a molten alloy.

Análisis cuantitativo de fusión por inducción de vacío mediante espectroscopía de ruptura inducida por láser

Vacuum induction melting is a popular method for refining high purity metal and alloys. Traditionally, standard process control in metallurgy involves ...

Method Development for Contactless Resonant Cavity Dielectric Spectroscopic Studies of Cellulosic Paper

The current analytical techniques for characterizing printing and graphic arts substrates are largely ex situ and destructive. This limits the amount of data that can be obtained from an individual sample and renders it difficult to produce statistically relevant data for unique and rare materials. Resonant cavity dielectric spectroscopy is a non-destructive, contactless technique which can simultaneously interrogate both sides of a sheeted material and provide measurements which are suitable for statistical interpretations. This offers analysts the ability to quickly discriminate between sheeted materials based on composition and storage history. In this methodology article, we demonstrate how contactless resonant cavity dielectric spectroscopy may be used to differentiate between paper analytes of varying fiber species compositions, to determine the relative age of the paper, and to detect and quantify the amount of post-consumer waste (PCW) recycled fiber content in manufactured office paper.

A protocol for the non-destructive analysis of the fiber content and relative age of paper.

Desarrollo del método para estudios espectroscópicos dieléctricos de cavidad resonante sin contacto de papel celulósico

The current analytical techniques for characterizing printing and graphic arts substrates are largely ex situ and destructive. This limits the amount of ...

Measurement of Chladni Mode Shapes with an Optical Lever Method

Quantitatively determining the Chladni pattern of an elastic plate is of great interest in both physical science and engineering applications. In this paper, a method of measuring mode shapes of a vibrating plate based on an optical lever method is proposed. Three circular acrylic plates were employed in the measurement under different center harmonic excitations. Different from a traditional method, only an ordinary laser pen and a light screen made of ground glass are employed in this novel approach. The approach is as follows: the laser pen projects a beam to the vibrating plate perpendicularly, and then the beam is reflected to the light screen in the distance, on which a line segment made of the reflected spot is formed. Due to the principle of vision persistence, the light spot could be read as a bright straight line. The relationship between the slope of the mode shape, length of the light spot and the distance of the vibrating plate and the light screen can be obtained with algebraic operations. Then the mode shape can be determined by integrating the slope distribution with suitable boundary conditions. The full-field mode shapes of Chladni plate could also be determined further in such a simple way.

A simple method of measuring the Chladni mode shape on an elastic plate by the principle of an optical lever is proposed.

Medición de formas de modo Chladni con un método de palanca óptica

Quantitatively determining the Chladni pattern of an elastic plate is of great interest in both physical science and engineering applications. In this ...