Ringraziamo il gruppo H.O.G presso la Arizona State University per lo sviluppo della metodologia iniziale di questi esperimenti idrotermali, e in particolare, ringraziamo I. Gould, Shock E., L. Williams, C. Gordana, H. Hartnett, K. Fecteau, K. Robinson e C. Bockisch, per loro orientamento e assistenza disponibile. Yang Z. e X. Fu erano finanziate da fondi di avvio da Oakland University a z Yang.

1. preparare il campione per esperimento idrotermale
<ol><li>Scegliere le dimensioni dei tubi di vetro quarzo o silice, per esempio, 2 mm diametro interno (ID) x 6 mm di diametro esterno (OD) o 6 mm ID x 12 mm OD anche e determinare la quantità di composti organici e minerali da utilizzare. In questo lavoro, gli importi di nitrobenzene e magnetite (Fe3O4) per caricare nel tubo di silice (ad es., 2 mm ID x 6 mm OD) sono 3,0 µ l e 13,9 mg, rispettivamente. Nota: I tubi di grande diametro consentono più facile caricamento dei materiali ma richiedono maggiori sforzi di tenuta del tubo.</li>
	<li>Tagliare il tubo di vetro pulito silice in piccoli pezzi con ~ 30 cm di lunghezza utilizzando un tagliatubi. Tenuta un'estremità del tubo chiuso utilizzando una torcia ossidrogeno con una testa di fiamma appropriato. Attenzione: Seguire le procedure di sicurezza per l'utilizzo della torcia ossidrogeno.</li>
	<li>Pesare la quantità predeterminata di partenza composto organico su un 0.1 mg-scala dell'equilibrio (se è solido) e trasferirlo nel tubo di vetro di silice utilizzando una carta di pesatura. Se il composto è liquido (ad es., nitrobenzene in questo caso), utilizzare una siringa di microlitro (ad es. 10 µ l) per trasferirlo nel tubo di silice. Aggiungere i minerali pesati nel tubo di silice mediante una pipetta Pasteur e quindi aggiungere acqua deionizzata e deossigenato (ad es., 0,3 mL). MΩ·cm uso 18,2 acqua deionizzata e si deoxygenate di sonicazione.</li>
	<li>Collegare il tubo di silice per una linea del vuoto (ID ~ 1 cm) con una valvola chiusa. Immergere il tubo in un pallone Dewar riempito con azoto liquido per ~ 3 min fino a quando le sostanze organiche e l'acqua sono completamente congelati. Attenzione: Seguire le procedure di sicurezza per il trasferimento e l'utilizzo di azoto liquido.</li>
	<li>Quando il tubo rimane immerso in azoto liquido, aprire la valvola del vuoto e rimuovere l'aria dallo spazio di testa del tubo. Nota: Questo processo dovrebbe durare fino a quando la pressione scende sotto 100 mtorr sul manometro della pompa del vuoto.</li>
	<li>Spegnere la valvola, rimuovere la provetta dall'azoto liquido e lasciare che il tubo caldo fino a temperatura ambiente. Picchiettare delicatamente il fondo della provetta per rilasciare le bolle d'aria rimanente dalla soluzione per spazio di testa.</li>
	<li>Ripetere il ciclo Disgelo-pompa sopra per altre due volte e tenere il tubo in azoto liquido prima di sigillare l'altra estremità del tubo. Chiudere la linea del vuoto e utilizzare la fiamma ossidrica per rendere l'intero tubo chiuso. Nota: Quando il tubo viene sottoposto a esperimenti idrotermali, diminuirà il volume dello spazio di testa del tubo a causa dell'espansione di acqua liquida. Ad esempio, la densità dell'acqua riduce circa il 30% da temperatura ambiente a 300 ° C. Calcolare e lasciare abbastanza volume di spazio di testa quando il tubo di tenuta.</li>
</ol>2. impostare l'esperimento idrotermale
<ol><li>Dopo i passaggi di sigillamento, mettere il tubo di silice in un piccolo tubo d'acciaio (~ 30 cm di lunghezza e 1,5 cm di diametro) con tappi a vite allentate, al fine di evitare danni da qualsiasi pressione edificio o guasto del tubo all'interno del tubo.</li>
	<li>Collocare il tubo in un forno o forno ben controllato di temperatura e calore fino alla temperatura desiderata (ad es., 150 ° C in questo lavoro). Utilizzare una termocoppia all'interno del forno per monitorare la temperatura attraverso la reazione idrotermale.</li>
	<li>Appena il tempo di reazione è raggiunta (ad es., 2 h in questo lavoro), placare il tubo di silice mettendo rapidamente il tubo in acqua e ghiaccio. Nota: Il processo di spegnimento dura meno di 1 min raffreddare a temperatura ambiente, che evita potenziali reazioni retrograde.</li>
</ol>3. analizzare il campione dopo l'esperimento
<ol><li>Aprire il tubo di silice utilizzando una taglierina per tubi e trasferire rapidamente tutti i prodotti (ad es., ~0.3 mL in tubo di silice) in un flaconcino di vetro da 10 mL utilizzando una pipetta Pasteur.</li>
	<li>Estrarre i prodotti biologici con 3 mL di diclorometano (DCM) soluzione contenente dodecano 8,8 mM come standard interno per gas cromatografia (GC). Tappo il flacone e agitare per passa per 2 min e vortice per 1 min. Nota: Ciò contribuisce a facilitare l'estrazione dei prodotti biologici nella fase organica. Inoltre, sciacquare le pareti conferente dispensare e all'interno del tubo di silice con DCM per garantire il recupero di prodotti. Per campioni con alto contenuto minerale, Sonicare li nella soluzione DCM per migliore estrazione.</li>
	<li>Consentire le particelle minerali di stabilirsi nella soluzione di estrazione (cioè, DCM con dodecano) per 5 min, uso una pipetta di Pasteur attentamente trasferire ~ 1 mL del campione dallo strato DCM (cioè, lo strato inferiore) in un flaconcino di GC.</li>
	<li>Analizzare la distribuzione di prodotti biologici mediante GC con una colonna di poli-capillare (per esempio, 5% diphenyl/95% dimetilsiloxano) e un rivelatore a ionizzazione di fiamma. Impostare il forno GC con un programma per iniziare a 50 ° C e tenere premuto per 8 min, aumentare a 10 ° C/min fino a 220 ° C e tenere premuto per 10 min, aumentare a 20 ° C/min a 300 ° C e tenere premuto per 5 min, impostare la temperatura iniettore a 300 ° C. Nota: Il programma di GC dovuto essere cambiate in base al tipo di composti organici analizzato.</li>
	<li>Costruire le curve di taratura GC tracciando il rapporto tra area del picco dell'analita per lo standard interno contro la concentrazione dell'analita.</li>
	<li>Calcolare la conversione di reazione basata sulle concentrazioni di materiale organico di partenza prima e dopo la reazione, cioè, conversione % = ([iniziale] – [finale]) ⁄ [iniziale] × 100%. Utilizzare le conversioni per determinare se il minerale facilita o rallenta le trasformazioni organiche idrotermale.</li>
</ol>

<ol>
	<li>Yang, Z., Gould, I. R., Williams, L. B., Hartnett, H. E., Shock, E. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+iron-containing+minerals+on+hydrothermal+reactions+of+ketones.">Effects of iron-containing minerals on hydrothermal reactions of ketones.</a> Geochimica et Cosmochimica Acta. 223, 107-126 (2018).</li><li>Seewald, J. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Organic-inorganic+interactions+in+petroleum-producing+sedimentary+basins.">Organic-inorganic interactions in petroleum-producing sedimentary basins.</a> Nature. 426 (6964), 327-333 (2003).</li><li>Sogin, M. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microbial+diversity+in+the+deep+sea+and+the+underexplored+"rare+biosphere".">Microbial diversity in the deep sea and the underexplored "rare biosphere".</a> Proceedings of the National Academy of Sciences. 103 (32), 12115 (2006).</li><li>McCollom, T. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Laboratory+Simulations+of+Abiotic+Hydrocarbon+Formation+in+Earth's+Deep+Subsurface.">Laboratory Simulations of Abiotic Hydrocarbon Formation in Earth's Deep Subsurface.</a> Reviews in Mineralogy and Geochemistry. 75 (1), 467-494 (2013).</li><li>Foustoukos, D. I., Seyfried, W. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hydrocarbons+in+Hydrothermal+Vent+Fluids:+The+Role+of+Chromium-Bearing+Catalysts.">Hydrocarbons in Hydrothermal Vent Fluids: The Role of Chromium-Bearing Catalysts.</a> Science. 304 (5673), 1002 (2004).</li><li>Bell, J. L. S., Palmer, D. A., Pittman, E. D., Lewan, M. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=10.1007/978-3-642-78356-2_9.">10.1007/978-3-642-78356-2_9.</a> Organic Acids in Geological Processes. , 226-269 (1994).</li><li>Palmer, D. A., Drummond, S. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thermal+decarboxylation+of+acetate.+Part+I.+The+kinetics+and+mechanism+of+reaction+in+aqueous+solution.">Thermal decarboxylation of acetate. Part I. The kinetics and mechanism of reaction in aqueous solution.</a> Geochimica et Cosmochimica Acta. 50 (5), 813-823 (1986).</li><li>Yang, Z., Gould, I. R., Williams, L. B., Hartnett, H. E., Shock, E. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+central+role+of+ketones+in+reversible+and+irreversible+hydrothermal+organic+functional+group+transformations.">The central role of ketones in reversible and irreversible hydrothermal organic functional group transformations.</a> Geochimica et Cosmochimica Acta. 98, 48-65 (2012).</li><li>McCollom, T. M., Ritter, G., Simoneit, B. R. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lipid+Synthesis+Under+Hydrothermal+Conditions+by+Fischer-+Tropsch-Type+Reactions.">Lipid Synthesis Under Hydrothermal Conditions by Fischer- Tropsch-Type Reactions.</a> Origins of life and evolution of the biosphere. 29 (2), 153-166 (1999).</li><li>Bell, J. L. S., Palmer, D. A., Barnes, H. L., Drummond, S. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thermal+decomposition+of+acetate:+III.+Catalysis+by+mineral+surfaces.">Thermal decomposition of acetate: III. Catalysis by mineral surfaces.</a> Geochimica et Cosmochimica Acta. 58 (19), 4155-4177 (1994).</li><li>Yang, Z., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hydrothermal+Photochemistry+as+a+Mechanistic+Tool+in+Organic+Geochemistry:+The+Chemistry+of+Dibenzyl+Ketone.">Hydrothermal Photochemistry as a Mechanistic Tool in Organic Geochemistry: The Chemistry of Dibenzyl Ketone.</a> The Journal of Organic Chemistry. 79 (17), 7861-7871 (2014).</li><li>Yang, Z., Hartnett, H. E., Shock, E. L., Gould, I. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Organic+Oxidations+Using+Geomimicry.">Organic Oxidations Using Geomimicry.</a> The Journal of Organic Chemistry. 80 (24), 12159-12165 (2015).</li><li>Venturi, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mineral-assisted+production+of+benzene+under+hydrothermal+conditions:+Insights+from+experimental+studies+on+C6+cyclic+hydrocarbons.">Mineral-assisted production of benzene under hydrothermal conditions: Insights from experimental studies on C6 cyclic hydrocarbons.</a> Journal of Volcanology and Geothermal Research. 346, 21-27 (2017).</li><li>Lemke, K. H., Rosenbauer, R. J., Bird, D. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Peptide+Synthesis+in+Early+Earth+Hydrothermal+Systems.">Peptide Synthesis in Early Earth Hydrothermal Systems.</a> Astrobiology. 9 (2), 141-146 (2009).</li><li>Byrappa, K., Yoshimura, M. <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 Hydrothermal Technology. , (2001).</li><li>Johnson, J. W., Oelkers, E. H., Helgeson, H. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=SUPCRT92:+A+software+package+for+calculating+the+standard+molal+thermodynamic+properties+of+minerals,+gases,+aqueous+species,+and+reactions+from+1+to+5000+bar+and+0+to+1000&#176;C.">SUPCRT92: A software package for calculating the standard molal thermodynamic properties of minerals, gases, aqueous species, and reactions from 1 to 5000 bar and 0 to 1000&#176;C.</a> Computers &amp; Geosciences. 18 (7), 899-947 (1992).</li></ol>

Gli autori non hanno nulla a rivelare.

In questo studio, abbiamo utilizzato il nitrobenzene con minerale magnetite come esempio per dimostrare come valutare minerali effetti sulle reazioni organiche idrotermale. Anche se gli esperimenti vengono eseguiti in tubi di vetro di silice, risultati altamente riproducibili sono osservati negli esperimenti magnetite, vale a dire, 30.3 ± 1,4% nella conversione di nitrobenzene, che suggerisce l'efficacia e l'affidabilità di questo protocollo di idrotermale. Negli esperimenti no-minerale, la conversione di nitr...

Ambienti idrotermali (cioè, mezzi acquosi ad elevate temperature e pressioni) sono onnipresenti sulla terra. La chimica idrotermale di composti organici gioca un ruolo essenziale in una vasta gamma di impostazioni geochimiche, come organici bacini sedimentari, serbatoi di petrolio e la biosfera profonda1,2,3. Le trasformazioni di carbonio organico in sistemi idrotermali si verificano non solo in puro mezzo acquoso ma anche con materiali inorganici disciolti o solidi, quali minerali abbondanti a terra. Minerali sono stati trovati per drammaticamente e selettivamente influenza la reattività idrotermale di vari composti organici,1,4,5 ma come identificare gli effetti minerali in complessi sistemi idrotermali rimane ancora una sfida. L'obiettivo di questo studio è quello di fornire un protocollo sperimentale relativamente semplice per studiare minerali effetti sulle reazioni organiche idrotermale.
Gli studi di laboratorio delle reazioni idrotermali utilizzano tradizionalmente robusti reattori che sono fatti di oro, titanio o in acciaio inox6,7,8,9. Ad esempio, sacchi d'oro o le capsule sono stati favorevolmente utilizzati, perché l'oro è flessibile, e permette la pressione del campione deve essere comandato da pressurizzazione dell'acqua esternamente, che evita la generazione di una fase di vapore all'interno del campione. Tuttavia, questi reattori sono costosi e potrebbero essere associati con potenziali effetti catalitici metallo10. Quindi, è assolutamente necessario trovare un metodo alternativo con basso costo ma di alta affidabilità per questi esperimenti idrotermali.
Negli ultimi anni, provette di vetro al quarzo o silice fusa sono state applicate più frequentemente al idrotermale esperimenti11,12,13. Rispetto al prezioso oro o titanio, vetro di quarzo o silice è notevolmente più economico, ma anche il materiale forte. Ancora più importante, tubi al quarzo hanno indicato gli effetti catalitici poco e può essere come inerte come l'oro per le reazioni idrotermali11,14. In questo protocollo, descriviamo un metodo generale per lo svolgimento di esperimenti organico-minerale idrotermali su piccola scala in tubi di silice con pareti spesse. Vi presentiamo un esperimento di esempio utilizzando un composto di modello (cioè, nitrobenzene) in presenza/assenza di un minerale di ossido di ferro (cioè, magnetite) in una soluzione idrotermale di 150 ° C, al fine di mostrare l'effetto minerale, anche per dimostrare la efficacia di questo metodo.

<table>
	<tbody>
		<tr>
			<td>Chemicals:</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Dichloromethane</td>
			<td>VWR</td>
			<td>BDH23373.400</td>
			<td></td>
		</tr>
		<tr>
			<td>Dodecane</td>
			<td>Sigma-Aldrich</td>
			<td>297879</td>
			<td></td>
		</tr>
		<tr>
			<td>Nitrobenzene</td>
			<td>Sigma-Aldrich</td>
			<td>252379</td>
			<td></td>
		</tr>
		<tr>
			<td>Fe2O3</td>
			<td>Sigma-Aldrich</td>
			<td>310050</td>
			<td></td>
		</tr>
		<tr>
			<td>Fe3O4</td>
			<td>Sigma-Aldrich</td>
			<td>637106</td>
			<td></td>
		</tr>
		<tr>
			<td>Supplies:</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Silica tube</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Vacuum pump</td>
			<td>WELCH</td>
			<td>2546B-01</td>
			<td></td>
		</tr>
		<tr>
			<td>Vacuum line</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Oven</td>
			<td>Hewlett Packard</td>
			<td>5890</td>
			<td></td>
		</tr>
		<tr>
			<td>Thermocouple</td>
			<td>BENETECH</td>
			<td>GM1312</td>
			<td></td>
		</tr>
		<tr>
			<td>Gas chromatography</td>
			<td>Agilent</td>
			<td>7820A</td>
			<td></td>
		</tr>
	</tbody>
</table>

an experimental protocol for studying mineral effects on organic hydrothermal transformations

Organico-minerale interazioni ampiamente si verificano in ambienti idrotermali, quali sorgenti termali, geyser sulla terra e le sorgenti idrotermali nell'oceano profondo. Ruoli dei minerali sono fondamentali in molti processi geochimici organici idrotermali. Tradizionale metodologia idrotermale, che include l'utilizzo di reattori in acciaio inox, titanio, platino o oro, è associata solitamente con il costo elevato o effetti catalitici metallici indesiderati. Recentemente, c'è una crescente tendenza per utilizzando i tubi di quarzo o silice fusa vetro convenienti e inerti negli esperimenti idrotermali. Qui, forniamo un protocollo per compiere esperimenti idrotermali in organico-minerale in tubi di silice, e descriviamo i passi essenziali nella preparazione dei campioni, messa a punto sperimentale, separazione di prodotti e analisi quantitativa. Inoltre dimostriamo un esperimento utilizzando un composto organico di modello, nitrobenzene, per mostrare l'effetto di un minerale contenente ferro, magnetite, sulla sua degradazione sotto una determinata condizione idrotermale. Questa tecnica può essere applicata per studiare complessi organo-minerali idrotermali interazioni in un sistema di laboratorio relativamente semplici.

Per illustrare come utilizzare questo approccio per studiare le interazioni organico-minerale idrotermale, un semplice esperimento utilizzando un composto di modello, nitrobenzene, è stata condotta con minerale magnetite (Fe3O4) in una condizione idrotermale di 150 ° C e 5 bar per 2 h. Per visualizzare l'effetto minerale, un esperimento di nitrobenzene senza minerale inoltre è stato effettuato nella stessa circostanza idrotermale. Come mostrato in <strong class="x...

Watch this Scientific Journal Video about An Experimental Protocol for Studying Mineral Effects on Organic Hydrothermal Transformations at JoVE.com

An Experimental Protocol for Studying Mineral Effects on Organic Hydrothermal Transformations

Terra-abbondanti minerali svolgono i ruoli importanti nei sistemi idrotermali naturali. Qui, descriviamo un metodo affidabile e conveniente per l'indagine sperimentale delle interazioni organico-minerale in condizioni idrotermali.

Un protocollo sperimentale per lo studio di minerali effetti sulle trasformazioni organiche idrotermale

Organic-mineral interactions are widely occurring in hydrothermal environments, such as hot springs, geysers on land, and the hydrothermal vents in the ...

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5.6K Views.  Oakland University. Terra-abbondanti minerali svolgono i ruoli importanti nei sistemi idrotermali naturali. Qui, descriviamo un metodo affidabile e conveniente per l'indagine sperimentale delle interazioni organico-minerale in condizioni idrotermali.

Video: An Experimental Protocol for Studying Mineral Effects on Organic Hydrothermal Transformations

Experimental Protocol for Manipulating Plant-induced Soil Heterogeneity

Coexistence theory has often treated environmental heterogeneity as being independent of the community composition; however biotic feedbacks such as plant-soil feedbacks (PSF) have large effects on plant performance, and create environmental heterogeneity that depends on the community composition. Understanding the importance of PSF for plant community assembly necessitates understanding of the role of heterogeneity in PSF, in addition to mean PSF effects. Here, we describe a protocol for manipulating plant-induced soil heterogeneity. Two example experiments are presented: (1) a field experiment with a 6-patch grid of soils to measure plant population responses and (2) a greenhouse experiment with 2-patch soils to measure individual plant responses. Soils can be collected from the zone of root influence (soils from the rhizosphere and directly adjacent to the rhizosphere) of plants in the field from conspecific and heterospecific plant species. Replicate collections are used to avoid pseudoreplicating soil samples. These soils are then placed into separate patches for heterogeneous treatments or mixed for a homogenized treatment. Care should be taken to ensure that heterogeneous and homogenized treatments experience the same degree of soil disturbance. Plants can then be placed in these soil treatments to determine the effect of plant-induced soil heterogeneity on plant performance. We demonstrate that plant-induced heterogeneity results in different outcomes than predicted by traditional coexistence models, perhaps because of the dynamic nature of these feedbacks. Theory that incorporates environmental heterogeneity influenced by the assembling community and additional empirical work is needed to determine when heterogeneity intrinsic to the assembling community will result in different assembly outcomes compared with heterogeneity extrinsic to the community composition.

Understanding the role of environmental heterogeneity in species coexistence has typically focused on types of heterogeneity that are extrinsic to the community&#8217;s species composition. We provide novel detailed methods for creating soil heterogeneity treatments using soils subject to plant-soil feedback conditioning, or heterogeneity intrinsic to the community composition.

Protocollo sperimentale per eterogeneità del terreno manipolazione Plant-indotta

Coexistence theory has often treated environmental heterogeneity as being independent of the community composition; however biotic feedbacks such as ...

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Evaluation of Integrated Anaerobic Digestion and Hydrothermal Carbonization for Bioenergy Production

Lignocellulosic biomass is one of the most abundant yet underutilized renewable energy resources. Both anaerobic digestion (AD) and hydrothermal carbonization (HTC) are promising technologies for bioenergy production from biomass in terms of biogas and HTC biochar, respectively. In this study, the combination of AD and HTC is proposed to increase overall bioenergy production. Wheat straw was anaerobically digested in a novel upflow anaerobic solid state reactor (UASS) in both mesophilic (37 &#176;C) and thermophilic (55 &#176;C) conditions. Wet digested from thermophilic AD was hydrothermally carbonized at 230 &#176;C for 6 hr for HTC biochar production. At thermophilic temperature, the UASS system yields an average of 165 LCH4/kgVS&#160;(VS: volatile solids) and 121 L CH4/kgVS&#160;at mesophilic AD over the continuous operation of 200 days. Meanwhile, 43.4 g of HTC biochar with 29.6 MJ/kgdry_biochar was obtained from HTC of 1 kg digestate (dry basis) from mesophilic AD. The combination of AD and HTC, in this particular set of experiment yield 13.2 MJ of energy per 1 kg of dry wheat straw, which is at least 20% higher than HTC alone and 60.2% higher than AD only.

A novel Upflow Anaerobic Solid State (UASS) reactor was used for biogas production from fibrous feedstock. Digestate from UASS reactor was hydrothermally carbonized into HTC biochar in a pressurized batch reactor. The integration of the two bioenergy concepts was applied in this study to increase overall bioenergy production.

Valutazione della gestione integrata digestione anaerobica e carbonizzazione idrotermale per Bioenergy Production

Lignocellulosic biomass is one of the most abundant yet underutilized renewable energy resources. Both anaerobic digestion (AD) and hydrothermal ...

Exploring the Effects of Atmospheric Forcings on Evaporation: Experimental Integration of the Atmospheric Boundary Layer and Shallow Subsurface

Evaporation is directly influenced by the interactions between the atmosphere, land surface and soil subsurface. This work aims to experimentally study evaporation under various surface boundary conditions to improve our current understanding and characterization of this multiphase phenomenon as well as to validate numerical heat and mass transfer theories that couple Navier-Stokes flow in the atmosphere and Darcian flow in the porous media. Experimental data were collected using a unique soil tank apparatus interfaced with a small climate controlled wind tunnel. The experimental apparatus was instrumented with a suite of state of the art sensor technologies for the continuous and autonomous collection of soil moisture, soil thermal properties, soil and air temperature, relative humidity, and wind speed. This experimental apparatus can be used to generate data under well controlled boundary conditions, allowing for better control and gathering of accurate data at scales of interest not feasible in the field. Induced airflow at several distinct wind speeds over the soil surface resulted in unique behavior of heat and mass transfer during the different evaporative stages.

A protocol for the design and construction of a soil tank interfaced to a small climate controlled wind tunnel to study the effects of atmospheric forcings on evaporation is presented. Both the soil tank and wind tunnel are instrumented with sensor technologies for the continuous in situ measurement of environmental conditions.

Esplorare gli effetti dell&#39;inquinamento atmosferico forcing per evaporazione: Integrazione sperimentale dello strato atmosferica Boundary e Subsurface Shallow

Evaporation is directly influenced by the interactions between the atmosphere, land surface and soil subsurface. This work aims to experimentally study ...

Experimental Protocol for Detecting Cyanobacteria in Liquid and Solid Samples with an Antibody Microarray Chip

Global warming and eutrophication make some aquatic ecosystems behave as true bioreactors that trigger rapid and massive cyanobacterial growth; this has relevant health and economic consequences. Many cyanobacterial strains are toxin producers, and only a few cells are necessary to induce irreparable damage to the environment. Therefore, water-body authorities and administrations require rapid and efficient early-warning systems providing reliable data to support their preventive or curative decisions. This manuscript reports an experimental protocol for the in-field detection of toxin-producing cyanobacterial strains by using an antibody microarray chip with 17 antibodies (Abs) with taxonomic resolution (CYANOCHIP). Here, a multiplex fluorescent sandwich microarray immunoassay (FSMI) for the simultaneous monitoring of 17 cyanobacterial strains frequently found blooming in freshwater ecosystems, some of them toxin producers, is described. A microarray with multiple identical replicates (up to 24) of the CYANOCHIP was printed onto a single microscope slide to simultaneously test a similar number of samples. Liquid samples can be tested either by direct incubation with the antibodies (Abs) or after cell concentration by filtration through a 1- to 3-&#956;m filter. Solid samples, such as sediments and ground rocks, are first homogenized and dispersed by a hand-held ultrasonicator in an incubation buffer. They are then filtered (5 - 20 &#956;m) to remove the coarse material, and the filtrate is incubated with Abs. Immunoreactions are revealed by a final incubation with a mixture of the 17 fluorescence-labeled Abs and are read by a portable fluorescence detector. The whole process takes around 3 h, most of it corresponding to two 1-h periods of incubation. The output is an image, where bright spots correspond to the positive detection of cyanobacterial markers.

Experimental Protocol for Detecting Cyanobacteria in Liquid and Solid Samples with an Antibody Microarray Chip

The presence of cyanobacterial toxins in fresh water reservoirs for human consumption is a major concern for water management authorities. To evaluate the risk of water contamination, this article describes an protocol for the in-field detection of cyanobacterial strains in liquid and solid samples by using an antibody microarray chip.

Protocollo sperimentale per il rilevamento<em&gt; cianobatteri</em&gt; In campioni liquidi e solidi con un anticorpo Microarray chip

Global warming and eutrophication make some aquatic ecosystems behave as true bioreactors that trigger rapid and massive cyanobacterial growth; this has ...

Protocol for Microplastics Sampling on the Sea Surface and Sample Analysis

Microplastic pollution in the marine environment is a scientific topic that has received increasing attention over the last decade. The majority of scientific publications address microplastic pollution of the sea surface. The protocol below describes the methodology for sampling, sample preparation, separation and chemical identification of microplastic particles. A manta net fixed on an &#187;A frame&#171; attached to the side of the vessel was used for sampling. Microplastic particles caught in the cod end of the net were separated from samples by visual identification and use of stereomicroscopes. Particles were analyzed for their size using an image analysis program and for their chemical structure using ATR-FTIR and micro FTIR spectroscopy. The described protocol is in line with recommendations for microplastics monitoring published by the Marine Strategy Framework Directive (MSFD) Technical Subgroup on Marine Litter. This written protocol with video guide will support the work of researchers that deal with microplastics monitoring all over the world.

The protocol below describes the methodology for: microplastics sampling on the sea surface, separation of microplastic and chemical identification of particles. This protocol is in line with the recommendations for microplastics monitoring published by the MSFD Technical Subgroup on Marine Litter.

Protocollo per microplastiche campionamento sulla superficie del mare e Analisi dei campioni

Microplastic pollution in the marine environment is a scientific topic that has received increasing attention over the last decade. The majority of ...

Protocol for Assessing the Relative Effects of Environment and Genetics on Antler and Body Growth for a Long-lived Cervid

Cervid phenotype can be placed into one of two categories: efficiency, which promotes survival over extravagant morphometric growth, and luxury, which promotes growth of large weaponry and body size. Populations of the same species display each phenotype depending on environmental conditions. Although antler and body size of male white-tailed deer (Odocoileus virginianus) varies by physiographic region in Mississippi, USA and is strongly correlated with regional variation in nutritional quality, the effects of population-level genetics from native stocks and previous re-stocking efforts cannot be disregarded. This protocol describes how we designed a controlled study, where other factors that influence phenotype, such as age and nutrition, are controlled. We brought wild-caught pregnant females and six-month-old fawns from three distinct physiographic regions in Mississippi, USA to the Mississippi State University Rusty Dawkins Memorial Deer Unit. Deer from the same region were bred to produce a second generation of offspring, allowing us to assess generational responses and maternal effects. All deer ate the same high-quality (20% crude protein deer pellet) diet ad libitum. We uniquely marked each neonate and recorded body mass, hind foot, and total body length. Each subsequent fall, we sedated individuals via remote injection and sampled the same morphometrics plus antlers of adults. We found that all morphometrics increased in size from first to second generation, with full compensation of antler size (regional variation no longer present) and partial compensation of body mass (some evidence of regional variation) evident in the second generation. Second generation males that originated from our poorest quality soil region displayed about a 40% increase in antler size and about a 25% increase in body mass when compared to their wild harvested counterparts. Our results suggest phenotypic variation of wild male white-tailed deer in Mississippi are more related to differences in nutritional quality than population-level genetics.

Phenotypic differences among cervid populations may be related to population-level genetics or nutrition; discerning which is difficult in the wild. This protocol describes how we designed a controlled study where nutritional variation was eliminated. We found that phenotypic variation of male white-tailed deer was more limited by nutrition than genetics.

Protocollo per la valutazione degli effetti relativi di ambiente e genetica sulla Antler e la crescita del corpo per un cervide longevo

Cervid phenotype can be placed into one of two categories: efficiency, which promotes survival over extravagant morphometric growth, and luxury, which ...

Experimental Column Setup for Studying Anaerobic Biogeochemical Interactions Between Iron (Oxy)Hydroxides, Trace Elements, and Bacteria

Fate and speciation of trace elements (TEs), such as arsenic (As) and mercury (Hg), in aquifers are closely related to physio-chemical conditions, such as redox potential (Eh) and pH, but also to microbial activities that can play a direct or indirect role on speciation and/or mobility. Indeed, some bacteria can directly oxidize As(III) to As(V) or reduce As(V) to As(III). Likewise, bacteria are strongly involved in Hg cycling, either through its methylation, forming the neurotoxin monomethyl mercury, or through its reduction to elemental Hg&#176;. The fates of both As and Hg are also strongly linked to soil or aquifer composition; indeed, As and Hg can bind to organic compounds or (oxy)hydroxides, which will influence their mobility. In turn, bacterial activities such as iron (oxy)hydroxide reduction or organic matter mineralization can indirectly influence As and Hg sequestration. The presence of sulfate/sulfide can also strongly impact these particular elements through the formation of complexes such as thio-arsenates with As or metacinnabar with Hg.
Consequently, many important questions have been raised on the fate and speciation of As and Hg in the environment and how to limit their toxicity. However, due to their reactivity towards aquifer components, it is difficult to clearly dissociate the biogeochemical processes that occur and their different impacts on the fate of these TE.
To do so, we developed an original, experimental, column setup that mimics an aquifer with As- or Hg-iron-oxide rich areas versus iron depleted areas, enabling a better understanding of TE biogeochemistry in anoxic conditions. The following protocol gives step by step instructions for the column set-up either for As or Hg, as well as an example with As under iron and sulfate reducing conditions.

Experimental Column Setup for Studying Anaerobic Biogeochemical Interactions Between Iron OxyHydroxides, Trace Elements, and Bacteria

Fate and speciation of arsenic and mercury in aquifers are closely related to physio-chemical conditions and microbial activity. Here, we present an original experimental column setup that mimics an aquifer and enables a better understanding of trace element biogeochemistry in anoxic conditions. Two examples are presented, combining geochemical and microbiological approaches.

Installazione colonna sperimentale per lo studio anaerobici biogeochimici interazioni tra batteri, oligoelementi e idrossidi di ferro (ossi)

Fate and speciation of trace elements (TEs), such as arsenic (As) and mercury (Hg), in aquifers are closely related to physio-chemical conditions, such as ...

Collection and Extraction of Occupational Air Samples for Analysis of Fungal DNA

Traditional methods of identifying fungal exposures in occupational environments, such as culture and microscopy-based approaches, have several limitations that have resulted in the exclusion of many species. Advances in the field over the last two decades have led occupational health researchers to turn to molecular-based approaches for identifying fungal hazards. These methods have resulted in the detection of many species within indoor and occupational environments that have not been detected using traditional methods. This protocol details an approach for determining fungal diversity within air samples through genomic DNA extraction, amplification, sequencing, and taxonomic identification of fungal internal transcribed spacer (ITS) regions. ITS sequencing results in the detection of many fungal species that are either not detected or difficult to identify to species level using culture or microscopy. While these methods do not provide quantitative measures of fungal burden, they offer a new approach to hazard identification and can be used to determine overall species richness and diversity within an occupational environment.

Determining the fungal diversity within an environment is a method utilized in occupational health studies to identify health hazards. This protocol describes DNA extraction from occupational air samples for amplification and sequencing of fungal ITS regions. This approach detects many fungal species that can be overlooked by traditional assessment methods.

Raccolta e l'estrazione di campioni d'aria professionale per l'analisi del DNA fungoso

Traditional methods of identifying fungal exposures in occupational environments, such as culture and microscopy-based approaches, have several ...

Experimental Protocol for Detecting Mitochondrial Function in Hepatocytes Exposed to Organochlorine Pesticides

This paper presents detailed methods on detecting hepatic mitochondrial function for a better understanding the cause of metabolic disorders caused by environmental organochlorine pesticides (OCPs) in hepatocytes. HepG2 cells were exposed to &#946;-hexachlorocyclohexane (&#946;-HCH) for 24 h at an equivalent dose of internal exposure in general population. Ultrastructure in hepatocytes was examined by transmission electron microscopy (TEM) to show the damage of mitochondria. Mitochondrial function was further evaluated by mitochondrial fluorescence intensity, adenosine 5'-triphosphate (ATP) levels, oxygen consumption rate (OCR) and mitochondrial membrane potential (MMP) in HepG2 cells incubated with &#946;-HCH. The mitochondria fluorescence intensity after stained by mitochondrial green fluorescent probe was observed with a fluorescence microscopy. The luciferin-luciferase reaction was used to determine ATP levels. The MMP was detected by the cationic dye JC-1 and analyzed under flow cytometry. OCR was measured with an extracellular flux analyzer. In summary, these protocols were used in detecting mitochondrial function in hepatocytes with to investigate mitochondria damages.

Understanding the influence of environmental organochlorine pesticides (OCPs) on mitochondrial function in hepatocytes is important in exploring the mechanism of OCPs causing metabolic disorders. This paper presents detailed methods on detecting hepatic mitochondrial function.

Protocollo sperimentale per il rilevamento della funzione mitocondriale negli eparitociti esposti ai pesticidi organoclorina

This paper presents detailed methods on detecting hepatic mitochondrial function for a better understanding the cause of metabolic disorders caused by ...

The Hawaii Protocol for Scientific Monitoring of Coffee Berry Borer: a Model for Coffee Agroecosystems Worldwide

Coffee berry borer (CBB) is the most devastating insect pest for coffee crops worldwide. We developed a scientific monitoring protocol that is aimed at capturing and quantifying the dynamics and impact of this invasive insect pest as well as the development of its host plant across a heterogeneous landscape. The cornerstone of this comprehensive monitoring system is timely georeferenced data collection on CBB movement, coffee berry infestation, mortality by the fungus Beauveria bassiana, and coffee plant phenology via a mobile electronic data recording application. This electronic data collection system allows field records to be georeferenced through built-in global positioning systems, and is backed by a network of weather stations and records of farm management practices. Comprehensive monitoring of CBB and host plant dynamics is an essential part of an area-wide project in Hawaii to aggregate landscape-level data for research to improve management practices. Coffee agroecosystems in other parts of the world that experience highly variable environmental and socioeconomic factors will also benefit from implementing this protocol, in that it will drive the development of customized integrated pest management (IPM) to manage CBB populations.

Comprehensive monitoring of coffee berry borer and host plant dynamics is essential for aggregating landscape-level data to improve management of this invasive pest. Here, we present a protocol for scientific monitoring of coffee berry borer movement, infestation, mortality, coffee plant phenology, weather, and farm management via a mobile electronic data recording application.

Il protocollo di Hawaii per monitoraggio scientifico di Coffee Berry Borer: un modello per caffè agroecosistemi in tutto il mondo

Coffee berry borer (CBB) is the most devastating insect pest for coffee crops worldwide. We developed a scientific monitoring protocol that is aimed at ...