Os autores agradecem o Sr. JO Hornkohl para o interesse e discussão sobre computação de diatômicas pontos fortes da linha molecular. Este trabalho é em parte apoiada pelo Centro de Aplicações de Laser da Universidade de Tennessee Space Institute.

1. Configuração do sistema óptico <ol><li> Coloque um divisor de feixe na saída do laser, permitindo que a luz de comprimento de onda 1064 nm a passar através e para reflectir todos os outros tipos de radiação laser de transiente num depósito de feixe. </li><li> Coloque um detector de fotodiodo PIN de alta velocidade para gravar uma parte da radiação laser refletido fora do divisor de feixe. Ligue o detector para o osciloscópio com cabo coaxial para controlar o impulso óptico em relação ao disparo do gerador de função e ocorrência de Q-na comutação de Nd: YAG laser dispositivo. </li><li> Alinhe três IR espelhos refletores para posicionar o feixe paralelo à fenda do espectrômetro. </li><li> Posicionar uma lente acima etapa de translação para concentrar o feixe, de modo a gerar plasma óptico repartição paralela à fenda espectrómetro. Alinhar duas lentes de quartzo com a finalidade de imagiologia do plasma para a fenda. As duas lentes de focagem optimamente combinar com o design espectrómetro, significando o final da lente tem um apertura para realizar AF # idêntico ao f # da óptica internos do espectrômetro. </li><li> Para as medições acima de 380 nm, uma posição de corte de filtro entre as duas lentes com o propósito de bloquear a radiação abaixo de 380 nm. O corte no filtro suprime possíveis contribuições UV (devido a 2 ª ordem de ralar) para o espectro medido. </li></ol> 2. Instalação de Aquisição de Dados <ol><li> Conecte um gerador de função em forma de onda proporcionando uma onda triangular a 50 Hz para um costume construído divisão por cinco circuito obter 10 Hz. O analisador multicanal óptico (OMA) é operado a 50 Hz e as lâmpadas de flash do laser Nd: YAG são sincronicamente operado a 10 Hz. Pode-se utilizar uma ICCD em lugar da OMA, operando de forma síncrona à taxa da radiação laser pulsado bem. </li><li> Conecte uma das saídas do circuito personalizado construído divisão por cinco a um gerador de atraso digital. Use uma saída para sincronizar o Nd: YAG lâmpadas de flash e outra saída para control os gatilhos de intensificador de arranjo de diodos linear e analisador multicanal óptico. Mais uma vez, em vez do sistema de díodos linear intensificada e OMA pode-se utilizar um ICCD. </li><li> Relé da saída de disparo ajustável do dispositivo a laser para um osciloscópio e um gerador de pulsos. O osciloscópio será utilizado para monitorizar quando a radiação laser pulsado estarão disponíveis para a geração de desagregação óptico ou ablação a laser. </li><li> Ligar a saída de alta voltagem do gerador de impulsos digital para o arranjo de diodos linear intensificada. </li><li> Ligar a outra saída do gerador de impulsos para o osciloscópio. </li><li> Ligue a saída de arranjo de diodos linear intensificada para a OMA. </li></ol> 3. Sincronização e Mensuração <ol><li> Ajuste o gerador de função em forma de onda de saída de um pulso triângulo operando a 50 ± 1 Hz. Este gerador de função apresenta a frequência mestre. Um costume construído circuito de divisão por cinco e um gerador de atraso digital são usados ​​para accurador de sincronização. </li><li> Iniciado sistema de resfriamento de água e fornecimento de energia para o dispositivo a laser. Ative laser. </li><li> Determine o tempo de radiação laser para viajar a partir da abertura de saída do laser Nd: YAG para a área em frente da fenda espectrómetro como se segue: Medir a distância do percurso de luz e calcular o tempo de trânsito através do aumento de velocidade-de luz. Conta para isso o tempo de trânsito na definição do tempo de atraso no portão próximo passo. </li><li> No gerador de pulso digital, definir a largura portão para a medição eo tempo de atraso da quebra pulso óptico ou ablação a laser, e utilizar o osciloscópio para monitorar o tempo de atraso. O tempo de atraso vai determinar o tempo de espera para a coleta de dados após o colapso ocorre. A largura da porta determina o tempo que o arranjo de diodos é exposto a radiação de plasma. </li><li> Gerar desagregação óptico no ar e / ou colocar uma amostra sobre a fase de translação de modo a que irá ocorrer a ablação. Imagem da microplasma na fenda espectrómetro. </li><li> Comece medições e dados de registro com a matriz intensificou linear diodo e analisador multicanal óptico (ou com um ICCD). </li></ol> 4. Calibração de comprimento de onda <ol><li> Espectros Registro de lâmpadas padrão de calibração: néon, mercúrio e lâmpadas de hidrogênio. Use o arranjo experimental com lâmpadas colocadas no local onde foi gerado plasma. </li><li> Usando os comprimentos de onda conhecidos de lâmpadas, realizar um ajuste linear ou cúbica para obter a correspondência de pixel-comprimento de onda. O propósito de uma calibração precisa é corrigir para não-linearidades que são normalmente associados com a medição de espectros. </li><li> Repita calibrações para H, C 2, CN, e TiO regiões espectrais de interesse. </li></ol> 5. Calibração Intensidade <ol><li> Ligue uma lâmpada de calibração de tungstênio e esperar por ele para se aquecer. </li><li> Use um pirômetro óptico para medir a temperatura da lâmpada ativa. </li><li> Use o arranjo experimental para rECORD o espectro da lâmpada activo. </li><li> Calcule uma curva de corpo negro de lei de radiação de Plank usando a temperatura medida como um parâmetro de entrada. </li><li> Ajustar a curva calculada para o espectro da lâmpada ativa. Determinar os fatores pelos quais as intensidades gravados a partir da curva calculada. Aplicar esses fatores para corrigir espectros gravada para a sensibilidade dependente do comprimento de onda do detector. </li><li> Repita esse procedimento para cada região do espectrômetro foi usado. </li></ol> 6. Transferência de Dados <ol><li> Prepare meio de transferências de arquivos. </li><li> Para cada medição de dados, gravá-la para o meio. </li><li> Tome este meio e fazer o upload dos arquivos nele a um computador de trabalho. </li></ol> 7. Preparação de Arquivos <ol><li> Para cada arquivo, analisá-lo em seções, uma contendo dados gravados, e os outros, especificando o comprimento de onda inicial e mudança de comprimento de onda média por ponto de dados. </li><li> Use estas seções para criar um novo arquivo para combinarcomprimentos de onda com dados gravados. </li></ol> 8. Análise Molecular Diatomic <ol><li> Selecione o arquivo de comprimento de onda e correspondente arquivo de resistência da linha. </li><li> Selecione o deslocamento da linha de base. <ol><li> Defina se o deslocamento é constante, linear, ou quadrática. </li><li> Defina os coeficientes correspondentes a valores fixos ou variáveis. </li></ol></li><li> Definir a resolução e temperatura, os quais podem ser fixos ou variado. </li><li> Defina a tolerância de ajuste para os espectros sintéticos para estar apto para o espectro medido. </li><li> Coloque a computado para os espectros experimental utilizando um algoritmo Nelder-Mead. </li><li> Utilizando os melhores parâmetros de ajuste dos espectros calculado para cada medição, inferir os parâmetros Microplasma observados nos vários atrasos e larguras de portas usadas. </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 os autores declaram que não têm interesses financeiros concorrentes.

O tempo resolveu protocolo de medição e resultados representativos são discutidos aqui. É importante sincronizar os pulsos de laser, gerada a uma velocidade de 10 Hz, com a frequência de funcionamento de 50 Hz de matriz linear intensificada diodo e OMA (ou ICCD). Além disso, o tempo exato de pulsos de laser e de abertura do portão da matriz intensificou linear diodo (ou, alternativamente, ICCD) é essencial. O gerador de onda, indicada no esquema experimental, é utilizado para sincronizar os pulsos de laser de d...

Espectroscopia de decomposição induzida por laser (LIBS) técnicas 1-5 têm aplicações em atômica 6-12 e estudos moleculares de plasma 13-20 gerado com a radiação laser. Espectroscopia resolvida no tempo é essencial para a determinação das características transientes do plasma. A temperatura ea densidade de elétrons, para citar apenas dois parâmetros do plasma, pode ser medido, desde um modelo teórico razoável da repartição plasma está disponível. Separação de radiação de elétrons livres de emissões atômicas e moleculares nos permite explorar de forma precisa fenômenos transitórios. Ao se concentrar em uma janela temporal, específico, pode-se &quot;congelar&quot; decadência plasma e assim obter as impressões digitais espectroscópicas precisos. LIBS tem uma variedade de aplicações e, recentemente, o interesse em LIBS-diagnóstico mostra um aumento considerável quando medido pelo número de investigadores publicação no campo. Pico e femtosegundo gerado microplasma é de contínuointeresse de pesquisa, no entanto, os arranjos LIBS historicamente experimentais utilizam radiação laser nanossegundo. A Figura 1 mostra um arranjo experimental típico para espectroscopia de decomposição induzida por laser. Para este protocolo, a energia de quebra funcional para o feixe inicial é da ordem de 75 mJ de pulso, no comprimento de onda infravermelho de 1.064 nm. Esta energia de pulso pode ser ajustada conforme necessário. . Plasma é disperso pelo espectrómetro e medido com uma matriz linear intensificada diodo e OMA ou, alternativamente, trabalhada sobre um dispositivo 2-dimensional Charge Coupled Intensificado (ICCD) A Figura 2 ilustra o diagrama de temporização para experiências resolvida no tempo: a sincronização de impulsos radiação laser com leitura, gatilho pulso de laser, fogo laser, e demora portão aberto. Espectroscopia resolvida no tempo bem sucedida requer vários procedimentos de calibração. Estes procedimentos incluem calibração de comprimento de onda, de voltacorrecção do solo e, mais importante, a correcção de sensibilidade do detector. Sensibilidade corrigir dados são importantes para a comparação dos espectros medidos e modelado. Para um aumento da razão sinal-para-ruído, múltiplos acontecimentos de degradação induzida por laser são gravadas.

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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>
		</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>
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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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		<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>
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		<tr height="100">
			<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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		<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>
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		<tr height="60">
			<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>
		</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>
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		<tr height="100">
			<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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		<tr height="20">
			<td height="20" style="height:20px;width:216px;"></td>
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			<td style="width:119px;"></td>
			<td style="width:167px;"></td>
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		<tr height="80">
			<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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		<tr height="20">
			<td height="20" style="height:20px;width:216px;"></td>
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			<td height="40" style="height:40px;width:216px;">Nd:YAG Laser Line Mirror, 1,064 nm</td>
			<td style="width:71px;">Thorlabs</td>
			<td style="width:119px;">NB1-K13</td>
			<td style="width:167px;">Companies: Edmund Optics, Newport</td>
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			<td height="20" style="height:20px;width:216px;"></td>
			<td style="width:71px;"></td>
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			<td height="40" style="height:40px;width:216px;">1 in Fused Silica Bi-Convex Lens, uncoated</td>
			<td style="width:71px;">Newport</td>
			<td style="width:119px;">SBX031</td>
			<td style="width:167px;">Companies: Edmund Optics, Thorlabs</td>
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		<tr height="20">
			<td height="20" style="height:20px;width:216px;"></td>
			<td style="width:71px;"></td>
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		<tr height="60">
			<td height="60" style="height:60px;width:216px;">2 in Fused Silica Plano-Convex lens, uncoated</td>
			<td style="width:71px;">Newport</td>
			<td style="width:119px;">SPX049</td>
			<td style="width:167px;">Convex lens, f/4.&#160; Companies: Edmund Optics, Thorlabs</td>
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		<tr height="20">
			<td height="20" style="height:20px;width:216px;"></td>
			<td style="width:71px;"></td>
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		<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

Neste trabalho, apresentamos medidas resolvidas em tempo de espectros atômicos e diatômico seguinte composição óptica induzida por laser. Um arranjo típico de LIBS é usado. Aqui vamos operar um laser Nd: YAG com uma frequência de 10 Hz no comprimento de onda fundamental de 1.064 nm. Os 14 nsec pulsos com anenergy de 190 mJ / pulso estão focados para um tamanho 50 mM local para gerar um plasma de quebra óptico ou ablação a laser no ar. O microplasma é fotografada na fenda de entrada de um 0,6 m espectrômetro, e espectros são gravadas utilizando um 1800 ranhuras / mm ralar um arranjo de diodos linear intensificada e analisador multicanal óptico (OMA) ou um ICCD. De interesse são linhas atômicas Stark-ampliaram da série Balmer de hidrogênio para inferir a densidade de elétrons. Também elaborar medições de temperatura a partir de espectros de emissão de monóxido de alumínio diatômico (AlO), carbono (C 2), cianogênio (CN), e monóxido de titânio (TiO). Os procedimentos experimentais incluem wavelength e calibrações de sensibilidade. A análise dos espectros molecular gravado é conseguido pelo ajuste dos dados com resistências de linha tabelados. Além disso, simulações de Monte-Carlo tipo são realizadas para estimar as margens de erro. Medições resolvida no tempo são essenciais para o plasma transitória comumente encontrado em LIBS.

LIBS utiliza radiação laser pulsado para ionizar suficientemente para formar uma amostra de plasma. Repartição induzida por laser de substâncias gasosas vai criar plasma que está centrada sobre a região focal do feixe de excitação, enquanto a ablação a laser em superfícies sólidas produzirá plasma acima da superfície da amostra. O plasma é gerado por focagem da radiação óptica na ordem de 100 GW / cm 2, por pulsos de degradação nanossegundo. Para produzir plasma de ablação a laser, tipi...

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

Espécies moleculares e atômicas diatómicas resolvida no tempo são medidos utilizando LIBS. Os espectros são coletados em vários atrasos após a geração de plasma quebra óptico com Nd: YAG laser de radiação e são analisados ​​para inferir densidade de elétrons e temperatura.

Medição e Análise de hidrogênio atômico e Diatomic AlO Molecular, C<sub&gt; 2</sub&gt;, CN, e TiO Spectra Following induzida por laser Breakdown Optical

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 visualizações.  University of Tennessee Space Institute.  Espécies moleculares e atômicas diatómicas resolvida no tempo são medidos utilizando LIBS. Os espectros são coletados em vários atrasos após a geração de plasma quebra óptico com Nd: YAG laser de radiação e são analisados ​​para inferir densidade de elétrons e temperatura. 

Vídeo: 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.

Construção e Teste de Pilhas da moeda de baterias de lítio

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

Engenharia

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 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.

Induzida por laser Breakdown Spectroscopy: Uma Nova Abordagem para Mapeamento e Quantificação de nanopartículas em Organ Tissue

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.

Quantificação de concentrações de hidrogénio nas camadas superficiais e interface e materiais a granel através de perfis de profundidade com Análise reação 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.

Transferência Atacante induzida por laser 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.

Armadilha óptica carregamento de dielétrico micropartículas no ar

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

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.

Deposição de camada atômica de dióxido de vanádio e um modelo ótico de temperatura-dependente

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.

Análise quantitativa de indução a vácuo de fusão por espectroscopia de degradação induzida por laser

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

Cutting Procedures, Tensile Testing, and Ageing of Flexible Unidirectional Composite Laminates

Many body armor designs incorporate unidirectional (UD) laminates. UD laminates are constructed of thin (&#60;0.05 mm) layers of high-performance yarns, where the yarns in each layer are oriented parallel to each other and held in place using binder resins and thin polymer films. The armor is constructed by stacking the unidirectional layers in different orientations. To date, only very preliminary work has been performed to characterize the ageing of the binder resins used in unidirectional laminates and the effects on their performance. For example, during the development of the conditioning protocol used in the National Institute of Justice Standard-0101.06, UD laminates showed visual signs of delamination and reductions in V50, which is the velocity at which half of the projectiles are expected to perforate the armor, after ageing. A better understanding of the material property changes in UD laminates is necessary to comprehend the long-term performance of armors constructed from these materials. There are no current standards recommended for mechanically interrogating unidirectional (UD) laminate materials. This study explores methods and best practices for accurately testing the mechanical properties of these materials and proposes a new test methodology for these materials. Best practices for ageing these materials are also described.

The goal of the study was to develop protocols to prepare consistent specimens for accurate mechanical testing of high-strength aramid or ultra-high-molar-mass polyethylene-based flexible unidirectional composite laminate materials and to describe protocols for performing artificial ageing on these materials.

Procedimentos de corte, testes de tração e envelhecimento de laminados unidirecionais flexíveis compósitos

Many body armor designs incorporate unidirectional (UD) laminates. UD laminates are constructed of thin (&#60;0.05 mm) layers of high-performance yarns, ...

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.

Desenvolvimento de método para estudos espectroscópicos dielétricos de cavidade ressonante sem contato de papel Celulóico

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

Hydrogen Charging of Aluminum using Friction in Water

A new method of hydrogen charging of aluminum was developed by means of a friction in water (FW) procedure. This procedure can easily introduce high amounts of hydrogen into aluminum based on the chemical reaction between water and non-oxide coated aluminum.

In order to introduce high amounts of hydrogen in aluminum and aluminum alloys, a new method of hydrogen charging was developed, called the friction in water procedure.

Carregamento de hidrogênio de alumínio usando atrito na água

A new method of hydrogen charging of aluminum was developed by means of a friction in water (FW) procedure. This procedure can easily introduce high ...

Medição e Análise de hidrogênio atômico e Diatomic AlO Molecular, C

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