Name: chemical gardens as flow-through reactors simulating natural hydrothermal systems
Uploaded: 2015-11-18T14:00:00.000+00:00
Duration: 12 min 55 s
Description: Watch this Scientific Journal Video about Chemical Gardens as Flow-through Reactors Simulating Natural Hydrothermal Systems at JoVE.com

This research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. We acknowledge the support by the NASA Astrobiology Institute (Icy Worlds). L.M.B. is supported by the NAI through the NASA Postdoctoral Program, administered by Oak Ridge Associated Universities through a contract with NASA. J.E.N. was supported through a US Department of Education PR/Award #: P031C110019 administered through Citrus College. We acknowledge useful discussions with members of the NAI Thermodynamics, Disequilibrium, and Evolution Focus Group and the Blue Marble Space Institute of Science.

1.安全注意事项<ol><li>使用个人防护装备（实验室外套，护目镜，丁腈手套，合适的鞋），以防止对化学品泄漏或受伤。使用注射器和针头，并注意不要穿刺手套。实验安装过程中要小心通过与首先进行注射，以检查是否有泄漏的装置，双蒸H 2 O（DDH 2 O的），并检查反应瓶上的立场的稳定性，添加化学品前。 </li><li>进行这项实验与任何化学花园配方，但我们用来模拟深海通风口反应物之一是一种有害化学品，硫化钠;因此，做整个实验在通风橱内，以防止曝光。 <ol><li>仅打开在通风柜瓶子的硫化钠和放置通风橱用于称重硫化物内的平衡。始终保持含硫化物的解决方案通风柜内，因为它们释放出有毒的硫化氢气体，同时还保持硫化物Ë液体，锐器，以及固体废弃物的容器在通风橱。感兴趣的另一种反应物为Fe（II）Cl 2中•4H 2 O，从而氧化在暴露于空气中，所以要小心，以保持溶液缺氧和生长的化学花园下缺氧顶空（例如，N 2或Ar），总是在通风橱或手套箱。 </li></ol></li></ol> 2.设置注射实验<ol><li>通过切断底部1厘米的100毫升的透明玻璃的压顶血清瓶（20毫米卷边密封闭合型），用玻璃切割器，使得，倒立时，容器是向大气开放创建玻璃"注射瓶"。由于这是可重复使用的，清洁的1 M盐酸酸浴O / N小瓶，然后一个新的实验之前，DDH 2 O的冲洗干净。 </li><li>制备注射瓶（ 图1）。 <ol><li>收集一门20毫米隔20 mm铝卷边密封，以及0.5〜10微升塑料吸管尖。为16G注射器NEedle，小心刺穿隔膜的中心孔，然后取出并丢弃在适当的锐器废物容器的针。 </li><li>插入枪头进针孔，进入橡胶隔膜将面临小瓶的卷曲顶部内侧的侧面。通过隔膜推枪头，以便它戳出的另一侧。 </li><li>卷曲密封与枪头隔膜到注入容器，使防水密封。当密封，进一步推枪头通过隔膜，以便它向外部伸出。 </li><li>贴上1/16"内径清晰灵活的抗化学腐蚀油管枪头（管道长度应达到从注射小瓶注射泵）;向上滑动的防水密封。 注意:这将是喷射管，通过用为16G针的注射器从另一端送入。 </li><li>检查是否有泄漏:将10毫升注射器填充DDH 2 O的用为16G针头插入管的另一端（平滑的管滑动直到针，小心不要刺破管的壁上）。慢慢注入使得DDH 2 O的向上移动管并进入反应容器的底部。确保注射器/管，管件/提示和压密封件防水。 </li></ol></li><li>夹紧在支架上在通风橱中注射小瓶，从而使注射将饲料从小瓶的底部。 注:多个小瓶可设置在一次和由单独的注射器同时加入。 </li><li>设置的电极，用于测量膜电位跨越的化学花园壁。始终使用其领先的"内幕"，哪些是"外面"的化学花园相同的约定。 <ol><li>切割绝缘电线（例如，铜），其从内部反应容器到达到万用表或数据记录器的引线的长度。离开松弛一点点的电线定位。 </li><li>条〜3个毫米的连线裸露在那个将位于反应小瓶内部的端部。在将要连接到万用表引线，条约1cm电线的另一端​​。 </li><li>固定导线以衡量整个化工园区膜电位。用于电线，将里面去的化学花园:将其插入枪头从中流体将送入容器的开口。 </li><li>推线中轻轻以确保与注射溶液接触，却远没有那么它将堵塞喷射流。对于外界线:位置，以便它会在与溶液储存器但不与化学花园沉淀接触。 </li><li>带或以其他方式固定导线，使它们可以在注入小瓶内部的实验（图2）期间不会移动。 </li><li>附加的导线的另一端​​部到万用表，并固定导线，使这些端部也不会在整个实验移动。 </li></ol></li><li>设置N 2 </子&gt;输气管线，将每个送入注射瓶之一。 <ol><li>分割从在 N 2源气体进料成几个管，使得存在一个N 2进料每次注射小瓶中。 </li><li>将每个N 2管，使其供给到注射小瓶中的一个的顶部空间。 </li></ol></li></ol> 3.准备化工园成长解决方案<ol><li>制备贮存溶液，加入100毫升每个实验。注意:在这个例子中，使用75毫米的 Fe 2+和25mM的Fe 3+作为沉淀阳离子（ 表1）。 <ol><li>由第一鼓泡DDH 2 O的以 N 2气体为每100毫升〜15分钟创建缺氧的解决方案。 </li><li>称取并添加的FeCl 2•4H 2 O和的FeCl 3•6H 2 O，轻轻搅拌，以溶解（未大力以便不引入氧气）。 </li><li>试剂溶解后，立即resum铁2+ /铁E光冒泡3+ 以 N 2气体解决方案，同时注射准备。 </li></ol></li><li>选择任何两个在表1所示的主注射溶液，并准备各10ml的。填有10毫升注射器到7 ml的标记与每个解的（一个针筒每个溶液）。更换针头帽，备用。 </li><li>备将20毫升二次注射溶液（硫化钠-小心）。 表 1中所示填充两个10 ml的注射器到7 ml的标记用此溶液，更换针帽，备用。始终保持在通风柜含硫化物溶液和注射器。 </li><li>笔芯的双蒸水从步骤2.2.5 2 O注射器;这些将被用于冲洗注入管。 </li></ol> 4.启动主注入<ol><li>使用所需的数据记录器的膜电位测量。衡量一个分隔符每个实验的潜力E通道，并设置扫描速率，得到的数据点的期望的量（例如，对于一个2小时注射，记录电位，每30秒就足够了）。 </li><li>固定在通风橱可编程注射泵主喷射注射器。 </li><li>使用废物烧杯赶上滴，并设置在注射器泵以很快的速度注入，直到注射器既开始滴入烧杯中。然后停止喷射（为了确保这两个注射器开始注入以完全相同的电平）。 </li><li>重新编程注射泵以每小时2毫升注入（用于校准所使用的注射器的类型），但不打的开始。 </li><li>插入DDH 2 O的注射器进入两个塑料注射管，并注入使水填充透明管最多在其进入主储存器的孔。将注射器在支架上，上述的注射小瓶中。 </li><li>倾将100ml 的 Fe 2+ / Fe的3+储液进EA的CH小瓶。 </li><li>根据需要，以保持在实验缺氧用于注射的持续时间调节N 2气行的流动。 </li><li>小心覆盖气密密封容器小瓶（例如，使用封口膜;不阻碍透过玻璃的视图）和插入的N 2进料到每个小瓶中（图3）。 </li><li>带上DDH 2 O的注射器（在管道仍插）跌旁边初次注射针筒。小心地将注塑管关闭DDH 2 O的注射器针头，并立即将其直接传送到主注射器针头之一。 （小心不要刺破管的壁上。） </li><li>开始注射，并开始记录膜电位。 </li></ol> 5.启动二次注入: <ol><li> 3小时后击中停止注射泵，一旦化工园区结构已经形成（6毫升被注射后）（Figu重新4），不断地产生一个膜电位（图5）。 </li><li>小心地取出从注射泵的主注射针筒（但保持其连接到该管道使结构没有干扰）;设置它们在支架上在上面的小瓶中的流体的水平，以使流体不能回流到注射器。 </li><li>固定二次注入硫化物注射器在注射器泵，并重复步骤4.3和4.4。 </li><li>删除辅助注射器1在从注射泵一个时间，和，同时保持上述在小瓶中的流体的水平的注射器，重复步骤4.9，传送管路从主注射器到辅助注射器（图6）。警惕，从储存器到注射器中的流体压力不会引起流体回流到注射器，因为这可能崩溃的化学花园。 </li><li>当传输完成后，小心地固定二级注射器日Ë注射泵。 </li><li>重新计划的注射泵注入以每小时2毫升，并打开始继续注射用新的注射液。 </li><li>安全地处理主喷射注射器。 </li></ol> 6.结束实验<ol><li>首先停止注射泵，然后停止录音的膜电位和保存数据。 </li><li>关闭N 2流量和删除线和封口膜从注射血管。 </li><li>如果需要的话，样品贮存溶液或沉淀进行进一步的分析。要仔细清除水库的解决方案，而不是打扰沉淀，用25毫升吸管仔细移液器关闭储液在几个等份，并丢弃浪费烧杯中的解决方案。 </li><li>松开注入容器一次一个，并将溶液倒入在通风橱浪费转印烧杯中。使用DDH 2 O的冲洗出沉淀物件。 </li><li>来回取下注射器米注射器泵，并且从管中提取它们，让多余的注入流体流失到废物转移烧杯中。清空注射器进入废物烧杯中，并在保持在通风橱硫化物尖锐件容器处置注射器。 </li><li>取下实验瓶的管子和一个固体废物袋进行处置。解卷曲密封和处置隔，印章，枪头。 </li><li>冲洗出来的玻璃实验瓶中，浸泡在1 M盐酸酸浴O / N。 （注意-玻璃器皿一直在与硫化钠接触会释放出有毒的硫化氢气体时，放置在酸性保持酸浴的通风橱内。） </li></ol>

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A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+hydrothermally+precipitated+catalytic+iron+sulphide+membrane+as+a+first+step+toward+life.">A hydrothermally precipitated catalytic iron sulphide membrane as a first step toward life.</a> J. Mol. Evol. 39 (3), 231-243 (1994).</li><li>Barge, L. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pyrophosphate+Synthesis+in+Iron+Mineral+Films+and+Membranes+Simulating+Prebiotic+Submarine+Hydrothermal+Systems.">Pyrophosphate Synthesis in Iron Mineral Films and Membranes Simulating Prebiotic Submarine Hydrothermal Systems.</a> Geochim. Cosmochim. Ac. 128, 1-12 (2014).</li><li>McGlynn, S. E., Kanik, I., Russell, M. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Peptide+and+RNA+contributions+to+iron-sulphur+chemical+gardens+as+life's+first+inorganic+compartments,+catalysts,+capacitors+and+condensors.">Peptide and RNA contributions to iron-sulphur chemical gardens as life's first inorganic compartments, catalysts, capacitors and condensors.</a> Philos. T. R. Soc. S-A. 370, 3007-3022 (2012).</li><li>Cartwright, J. H. E., Escribano, B., Sainz-D&#237;az, C. I., Stocieck, L. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chemical-Garden+Formation,+Morphology,+and+Composition.+II.+Chemical+Gardens+in+Microgravity.">Chemical-Garden Formation, Morphology, and Composition. II. Chemical Gardens in Microgravity.</a> Langmuir. 27, 3294-3300 (2011).</li><li>Thouvenel-Romans, S., Steinbock, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Oscillatory+Growth+of+Silica+Tubes+in+Chemical+Gardens.">Oscillatory Growth of Silica Tubes in Chemical Gardens.</a> J. Am. Chem. Soc. 125, 4338-4341 (2003).</li><li>Batista, B. C., Cruz, P., Steinbock, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=From+Hydrodynamic+Plumes+to+Chemical+Gardens:+The+Concentration-Dependent+Onset+of+Tube+Formation.">From Hydrodynamic Plumes to Chemical Gardens: The Concentration-Dependent Onset of Tube Formation.</a> Langmuir. 30, 9123-9129 (2014).</li><li>Herschy, B., 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=An+origin-of-life+reactor+to+simulate+alkaline+hydrothermal+vents.">An origin-of-life reactor to simulate alkaline hydrothermal vents.</a> J. Mol. Evol. 79, 213-227 (2014).</li><li>Yamaguchi, A., Yamamoto, M., Takai, K., Ishii, T., Hashimoto, K., Nakamura, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electrochemical+CO2+Reduction+by+Ni-containing+Iron+Sulfides:+How+Is+CO2+Electrochemically+Reduced+at+Bisulfide-Bearing+Deep-sea+Hydrothermal+Precipitates?.">Electrochemical CO2 Reduction by Ni-containing Iron Sulfides: How Is CO2 Electrochemically Reduced at Bisulfide-Bearing Deep-sea Hydrothermal Precipitates?.</a> Electrochim. Acta. 141, 311-318 (2014).</li><li>Hansen, H. C. B., Guldberg, S., Erbs, M., Koch, C. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Kinetics+of+nitrate+reduction+by+green+rusts&#8212;effects+of+interlayer+anion+and+Fe+(II):+Fe+(III)+ratio.">Kinetics of nitrate reduction by green rusts&#8212;effects of interlayer anion and Fe (II): Fe (III) ratio.</a> Appl. Clay Sci. 18 (1), 81-91 (2001).</li><li>Trolard, F., Bourri&#233;, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fougerite+a+natural+layered+double+hydroxide+in+gley+soil:+habitus,+structure,+and+some+properties.">Fougerite a natural layered double hydroxide in gley soil: habitus, structure, and some properties.</a> Clay Minerals in Nature - Their Characterization, Modification and Application. , (2012).</li><li>van Oss, C. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Specifically+Impermeable+Precipitate+Membranes.">Specifically Impermeable Precipitate Membranes.</a> Surface and Colloid Science. , 115-144 (1984).</li><li>Baaske, P., 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=Extreme+accumulation+of+nucleotides+in+simulated+hydrothermal+pore+systems.">Extreme accumulation of nucleotides in simulated hydrothermal pore systems.</a> P. Natl. Acad. Sci. USA. 104, 9346-9351 (2007).</li></ol>

The authors declare that they have no competing financial interests.

通过注射方法的化学花园结构的形成可以通过连接包含产生沉淀反应离子任何两个解决方案来实现。有许多可能的反应系统，将产生的沉淀物的结构并发现反应离子和浓度的权利配方以生长所需结构是试验和错误的问题。注射溶液的流速由一个可编程注射器泵控制，这也可以实验之间变化，以模拟在自然系统中的流体流动的速率不同。化学园林结构取决于很多因素，包括组合物和流量，并且它是?...

"化学花园"是自组装开发无机沉淀物，其中对比化学物质的两种流体交互1,2。这些自组装的无机结构已经超过一个世纪的部分原因是由于他们的仿生外观的科学兴趣的主题，许多实验和理论研究已经进行，以了解化学园林系统3的各种复杂问题和可能的功能。化学园林自然的例子包括矿物"烟囱"的沉淀，围绕热水泉和冷泉增长，有人认为，这些可以提供合理的环境中生活出现4。为了发展一个化工园区模拟自然的热液喷口烟囱，水库的解决方案应该代表一个模拟的海洋成分和注射液应代表热液流体送入大海。这种O型的多功能性˚F实验不同的反应系统可以模拟几乎任何提议的海洋/热液流体化学，包括对早期地球或其它星球上的环境。在早期地球，海洋本来缺氧，酸性（pH值5-6），并且将含有溶解大气 CO 2和Fe 2+，以及铁III，镍离子， 锰离子，编号3-和NO 2 - 。此海水和超基洋壳之间的化学反应会产生含有氢和甲烷的碱性热液，在某些情况下硫化物（HS - ）4-8。形成在早期地球碱性通气环境烟囱可由此包含亚铁/铁羟基氧化物和铁/镍硫化物，并且已经提出，这些矿物质可能起到特定的催化和原酶功能朝向利用地球化学氧化还原/ pH梯度来驱动Metaboli游戏的出现SM 5。同样，在其他世界如可承办（或已托管）水/岩界面 - 例如早期的火星，木星的卫星木卫二，或土星的卫星土卫二 - 有可能是水/岩的化学能产生碱性发泄的环境能够驾驶生命起源前化学甚至提供可居住龛现存生命5,9-11。 经典的化学园实验涉及晶种的金属盐，例如，四水合氯化亚铁的FeCl 2•4H 2 O，浸没在含有反应性的阴离子， 如硅酸钠或"水玻璃"的溶液。金属盐溶解，创建包含的 Fe 2+的酸性溶液，随着更多的碱性溶液接口（含硅酸盐阴离子和OH - ）和被形成的无机膜的沉淀。在渗透压的膜膨​​胀，破裂，然后重新沉淀的t是新的流体界面。这个过程一直重复，直到晶体溶解，从而产生一个垂直取向的，自组织的沉淀结构具有复杂的形态在宏观和微观尺度。此沉淀过程导致横跨无机化学花园膜化学反衬解决方案的持续分离，带电物质穿过膜的差产生了膜电位12-14中 。化学花园结构是复杂的，表现出组分梯度从内部到外部13,15-19，和该结构的壁保持对比解决方案之间的分离很长时间，同时保持稍微渗透到离子。除了是一个理想的实验中用于教育目的（因为它们是简单，使课堂演示，并能教育学生的化学反应和自组织），化工园有科学意义的自我assemb交涉LY在动态，远离平衡系统，涉及可导致生产性的和有用的材料20,21的方法。 化学园林在实验室也可以通过注射方法进行培养，其中含有一种离子沉淀的溶液缓慢注入到包含所述共沉淀离子（或离子）的第二溶液。这导致类似于晶体生长实验化学花园结构的形成，不同之处在于该系统的性能和沉淀可更好地控制。注射方法有几个显著优点。它允许一个使用沉淀或结合物种的任何组合，以形成化学花园; 即多个沉淀离子可以结合到一个解决方案，和/或其它非沉淀组分可以被包括在任溶液，以吸附与沉淀物/反应。在化学产生的膜电位花园系统可以在注射实验来测定，如果一个电极结合到结构的内部，因此能够使系统的电化学研究。注射实验提供通过改变喷射率或总注射体积喂注射溶液成的化学园的内部受控的时间框架中的能力;因此，可以通过不同的解决方案依次饲料和使用沉淀的结构为陷阱或反应器中。结合，这些技术允许实验室模拟，可以在一个海底热液通风口都发生在一个天然化学花园系统的复杂过程，包括来自海洋之间许多同时沉淀反应形成的烟囱和泄流体（例如，制备金属硫化物，氢氧化物和/或碳酸盐和硅酸盐）5,22。这些技术也可以应用到任何化学花园反应体系，以允许形成新类型的的材料， 例如，分层管或管与吸附的反应性物质20,23。 我们这里详细的示例实验，其中包括两种化学花园，铁2+含结构在缺氧环境中的同步增长。在这个实验中，我们引入多磷酸盐和/或氨基酸的痕量到初始注射溶液，观察它们对结构的影响。的化工园区初步形成后，我们再切换注射液引入硫化物作为二次沉淀阴离子。膜电位的测定是在整个实验自动进行。本协议描述如何运行两个实验，在使用双注射泵一次;示所需的数据此过程的多次运行。相对较高的流量，在我们的实验中使用的水库和反应物浓度低pH值的目的是形成大烟囱沉淀在时间SC麦芽啤酒适合一天的实验室实验。然而，流体的流速在天然热水泉可以更加分散和（在早期地球系统 ，例如，Fe和S）沉淀物的浓度可能是震级低 4的命令;因此，结构化的沉淀物会形成较长的时间尺度和通风口可以活跃多年24,25几万。

<table><tbody><tr><td>Syringe Pump</td><td>Fisher</td><td>14-831-3</td><td>Dual or multiple channel, depending on desired number of simultaneous experiments</td></tr><tr><td>Ferrous chloride tetrahydrate</td><td>Fisher</td><td>I90500</td><td>Ferrous Chloride Tetrahydrate (Crystalline/Certified)</td></tr><tr><td>Ferric chloride hexahydrate</td><td>Fisher</td><td>I88-100</td><td>Ferric&amp;nbsp;Chloride&amp;nbsp;Hexahydrate&amp;nbsp;(Lumps/Certified ACS)</td></tr><tr><td>Sodium hydroxide</td><td>Sigma-Aldrich</td><td>S5881</td><td>reagent grade, &amp;ge;98%, pellets (anhydrous)</td></tr><tr><td>Sodium sulfide nonahydrate</td><td>Fisher</td><td>S425212</td><td>Sodium Sulfide Nonahydrate (Crystalline/Certified ACS). Store at -20&amp;nbsp;&amp;#176;C. Only open in a glove box or fume hood. Releases toxic H&lt;sub&gt;2&lt;/sub&gt;S gas; all sulfide-containing solutions must be kept in a glove box or fume hood.</td></tr><tr><td>Potassium pyrophosphate</td><td>Sigma-Aldrich</td><td>&lt;a href=&quot;http://www.sigmaaldrich.com/catalog/product/aldrich/322431?lang=en&amp;amp;region=US&quot;&gt;322431&lt;/a&gt;</td><td>97%</td></tr><tr><td>L-Alanine</td><td>Sigma-Aldrich</td><td>&lt;a href=&quot;http://www.sigmaaldrich.com/catalog/product/sigma/a7627?lang=en&amp;amp;region=US&quot;&gt;A7627&lt;/a&gt;</td><td></td></tr><tr><td>Syringes (10&amp;nbsp;cc)</td><td>Fisher</td><td>14-823-16E</td><td>BD&amp;trade; Syringe with Luer-Lok Tips (Without Needle)</td></tr><tr><td>Syringe needles (16&amp;nbsp;gauge)</td><td>Fisher</td><td>14-826-18B</td><td>BD&amp;trade; General Use and PrecisionGlide Hypodermic Needles, 16&amp;nbsp;G x 1.5 in. (38&amp;nbsp;mm)</td></tr><tr><td>Tubing</td><td>Cole Parmer</td><td>EW-06407-71</td><td>Tygon Lab Tubing, Non-DEHP, 1/16&quot; ID x 1/8&quot; OD</td></tr><tr><td>Aluminum seals</td><td>Fisher</td><td>0337523C</td><td>Thermo Scientific&amp;trade; National&amp;trade; Headspace 20&amp;nbsp;mm Crimp Seals</td></tr><tr><td>Gray butyl stoppers</td><td>Fisher</td><td>0337522AA</td><td>Thermo Scientific&amp;trade; National&amp;trade; 20&amp;nbsp;mm Septa for Headspace Vials</td></tr><tr><td>Serum bottles</td><td>Sigma-Aldrich</td><td>33110-U</td><td>Vials, crimp top, serum bottle, size 100 ml, clear glass, O.D. &amp;times; H 51.7 mm &amp;times; 94.5 mm. For these experiments, the bottom of the serum bottle should be cut off.</td></tr><tr><td>Pipette tips</td><td>VWR</td><td>53511-682</td><td>pipette tips 0.5-10 &amp;#956;l</td></tr><tr><td>Wire</td><td>McMaster-Carr</td><td>8073K661</td><td>Solid Single-Conductor Wire, UL 1007/1569, 20 AWG, 300 VAC</td></tr></tbody></table>

chemical gardens as flow-through reactors simulating natural hydrothermal systems

Here we report experimental simulations of hydrothermal chimney growth using injection chemical garden methods. The versatility of this type of experiment allows for testing of various proposed ocean / hydrothermal fluid chemistries that could have driven reactions toward the origin of life in environments on the early Earth, early Mars, or even other worlds such as the icy moons of the outer planets. We show experiments that include growth of chemical garden structures under anoxic conditions simulating the early Earth, inclusion of trace components of phosphates / organics in the injection solution to incorporate them into the structure, a switch of the injection solution to introduce a secondary precipitating anion, and the measurement of membrane potentials generated by chemical gardens. Using this method, self-assembling chemical garden structures were formed that mimic the natural chimneys precipitated at submarine hydrothermal springs, and these precipitates can be used successfully as flow-through reactors by feeding through multiple successive &#8220;hydrothermal&#8221; injections.

一旦注射溶液开始送入贮存溶液，化学花园沉淀开始形成在流体界面和该结构继续生长在注射（ 图4-7）的过程。在这里报导的实验中，第一次注射是氢氧化钠（其可以被修改以包括L-丙氨酸和/或焦磷酸），和贮存溶液是1:铁3+ /的 Fe 2+的3混合物，得到的混合-redox态氢氧化铁沉淀。化学花园通常表现出双色形态-一些作品沉淀的是深绿色（表示可能的混合氢氧化合物）等片呈橙（...

Watch this Scientific Journal Video about Chemical Gardens as Flow-through Reactors Simulating Natural Hydrothermal Systems at JoVE.com

Chemical Gardens as Flow-through Reactors Simulating Natural Hydrothermal Systems

We describe chemical garden formation via injection experiments that allow for laboratory simulations of natural chemical garden systems that form at submarine hydrothermal vents.

化工园为直通式反应器模拟自然热液系统

Here we report experimental simulations of hydrothermal chimney growth using injection chemical garden methods. The versatility of this type of experiment ...

chemical-gardens-as-flow-through-reactors-simulating-natural

Universidad San Sebastian

Research

JoVE Journal

Chemistry

14.4K 次观看.  California Institute of Technology. We describe chemical garden formation via injection experiments that allow for laboratory simulations of natural chemical garden systems that form at submarine hydrothermal vents.

视频: Chemical Gardens as Flow-through Reactors Simulating Natural Hydrothermal Systems

Millifluidics for Chemical Synthesis and Time-resolved Mechanistic Studies

Procedures utilizing millifluidic devices for chemical synthesis and time-resolved mechanistic studies are described by taking three examples. In the first, synthesis of ultra-small copper nanoclusters is described. The second example provides their utility for investigating time resolved kinetics of chemical reactions by analyzing gold nanoparticle formation using in situ X-ray absorption spectroscopy. The final example demonstrates continuous flow catalysis of reactions inside millifluidic channel coated with nanostructured catalyst.

Millifluidic devices are utilized for controlled synthesis of nanomaterials, time-resolved analysis of reaction mechanisms and continuous flow catalysis.

Millifluidics的化学合成和时间分辨机理研究

Procedures utilizing millifluidic devices for chemical synthesis and time-resolved mechanistic studies are described by taking three examples. In the ...

科研

生物工程

Continuous Flow Chemistry: Reaction of Diphenyldiazomethane with p-Nitrobenzoic Acid

Continuous flow technology has been identified as instrumental for its environmental and economic advantages leveraging superior mixing, heat transfer and cost savings through the &#34;scaling out&#34; strategy as opposed to the traditional &#34;scaling up&#34;. Herein, we report the reaction of diphenyldiazomethane with p-nitrobenzoic acid in both batch and flow modes. To effectively transfer the reaction from batch to flow mode, it is essential to first conduct the reaction in batch. As a consequence, the reaction of diphenyldiazomethane was first studied in batch as a function of temperature, reaction time, and concentration to obtain kinetic information and process parameters. The glass flow reactor set-up is described and combines two types of reaction modules with &#34;mixing&#34; and &#34;linear&#34; microstructures. Finally, the reaction of diphenyldiazomethane with p-nitrobenzoic acid was successfully conducted in the flow reactor, with up to 95% conversion of the diphenyldiazomethane in 11 min. This proof of concept reaction aims to provide insight for scientists to consider flow technology&#39;s competitiveness, sustainability, and versatility in their research.

Continuous Flow Chemistry: Reaction of Diphenyldiazomethane with p-Nitrobenzoic Acid

Flow chemistry carries environmental and economic advantages by leveraging superior mixing, heat transfer and cost benefits. Herein, we provide a blueprint to transfer chemical processes from batch to flow mode. The reaction of diphenyldiazomethane (DDM) with p-nitrobenzoic acid, conducted in batch and flow, was chosen for proof of concept.

连续流动化学: Diphenyldiazomethane 与p硝基苯甲酸的反应

Continuous flow technology has been identified as instrumental for its environmental and economic advantages leveraging superior mixing, heat transfer and ...

化学

Utilization of Stop-flow Micro-tubing Reactors for the Development of Organic Transformations

A new reaction screening technology for organic synthesis was recently demonstrated by combining elements from both continuous micro-flow and conventional batch reactors, coined stop-flow micro-tubing (SFMT) reactors. In SFMT, chemical reactions that require high pressure can be screened in parallel through a safer and convenient way. Cross-contamination, which is a common problem in reaction screening for continuous flow reactors, is avoided in SFMT. Moreover, the commercially available light-permeable micro-tubing can be incorporated into SFMT, serving as an excellent choice for light-mediated reactions due to a more effective uniform light exposure, compared to batch reactors. Overall, the SFMT reactor system is similar to continuous flow reactors and more superior than batch reactors for reactions that incorporate gas reagents and/or require light-illumination, which enables a simple but highly efficient reaction screening system. Furthermore, any successfully developed reaction in the SFMT reactor system can be conveniently translated to continuous-flow synthesis for large scale production.

A protocol for organic reaction screening using stop-flow micro-tubing (SFMT) reactors employing gaseous reactants and/or visible-light mediated reactions is presented.

停止流动微管反应器在有机转化发展中的应用

A new reaction screening technology for organic synthesis was recently demonstrated by combining elements from both continuous micro-flow and conventional ...

Microalgae Cultivation and Biomass Quantification in a Bench-Scale Photobioreactor with Corrosive Flue Gases

Photobioreactors are illuminated cultivation systems for experiments on phototrophic microorganisms. These systems provide a sterile environment for microalgal cultivation with temperature, pH, and gas composition and flow rate control. At bench-scale, photobioreactors are advantageous to researchers studying microalgal properties, productivity, and growth optimization. At industrial scales, photobioreactors can maintain product purity and improve production efficiency. The video describes the preparation and use of a bench-scale photobioreactor for microalgal cultivation, including the safe use of corrosive gas inputs, and details relevant biomass measurements and biomass productivity calculations. Specifically, the video illustrates microalgal culture storage and preparation for inoculation, photobioreactor assembly and sterilization, biomass concentration measurements, and a logistic model for microalgal biomass productivity with rate calculations including maximum and overall biomass productivities. Additionally, since there is growing interest in experiments to cultivate microalgae using simulated or real waste gas emissions, the video will cover the photobioreactor equipment adaptations necessary to work with corrosive gases and discuss safe sampling in such scenarios.

Bench-scale, axenic cultivation facilitates microalgal characterization and productivity optimization before subsequent process scale-up. Photobioreactors provide the necessary control for reliable and reproducible microalgal experiments and can be adapted to safely cultivate microalgae with the corrosive gases (CO2, SO2, NO2) from municipal or industrial combustion emissions.

具有腐蚀性烟气的台式光生物反应器中的微藻培养和生物量定量

Photobioreactors are illuminated cultivation systems for experiments on phototrophic microorganisms. These systems provide a sterile environment for ...

环境科学

Coupling Carbon Capture from a Power Plant with Semi-automated Open Raceway Ponds for Microalgae Cultivation

In the United States, 35% of the total carbon dioxide (CO2) emissions come from the electrical power industry, of which 30% represent natural gas electricity generation. Microalgae can biofix CO2 10 to 15 times faster than plants and convert algal biomass to products of interest, such as biofuels. Thus, this study presents a protocol that demonstrates the potential synergies of microalgae cultivation with a natural gas power plant situated in the southwestern United States in a hot semi-arid climate. State-of-the-art technologies are used to enhance carbon capture and utilization via the green algal species Chlorella sorokiniana, which can be further processed into biofuel. We describe a protocol involving a semi-automated open raceway pond and discuss the results of its performance when it was tested at the Tucson Electric Power plant, in Tucson, Arizona. Flue gas was used as the main carbon source to control pH, and Chlorella sorokiniana was cultivated. An optimized medium was used to grow the algae. The amount of CO2 added to the system as a function of time was closely monitored. Additionally, other physicochemical factors affecting algal growth rate, biomass productivity, and carbon fixation were monitored, including optical density, dissolved oxygen (DO), electroconductivity (EC), and air and pond temperatures. The results indicate that a microalgae yield of up to 0.385 g/L ash-free dry weight is attainable, with a lipid content of 24%. Leveraging synergistic opportunities between CO2 emitters and algal farmers can provide the resources required to increase carbon capture while supporting the sustainable production of algal biofuels and bioproducts.

A protocol is described to utilize the carbon dioxide in natural gas power plant flue gas to cultivate microalgae in open raceway ponds. Flue gas injection is controlled with a pH sensor, and microalgae growth is monitored with real time measurements of optical density.

将发电厂的碳捕获与半自动开放式管道池相结合，用于微藻养殖

In the United States, 35% of the total carbon dioxide (CO2) emissions come from the electrical power industry, of which 30% represent natural gas ...

Simulation of Early Earth Hydrothermal Chimneys in a Thermal Gradient Environment

Deep sea hydrothermal vents are self-organizing precipitates generated from geochemical disequilibria and have been proposed as a possible setting for the emergence of life. The growth of hydrothermal chimneys in a thermal gradient environment within an early Earth vent system was successfully simulated by using different hydrothermal simulants, such as sodium sulfide, which were injected into an early Earth ocean simulant containing dissolved ferrous iron. Moreover, an apparatus was developed to sufficiently cool the ocean simulant to near 0 &#176;C in a condenser vessel immersed in a cold water bath while injecting a sulfide solution at hot to room temperatures, effectively creating an artificial chimney structure in a temperature gradient environment over a period of a few hours. Such experiments with different chemistries and variable temperature&#160;gradients resulted in a variety of morphologies in the chimney structure. The use of ocean and hydrothermal fluid simulants at room temperature resulted in vertical chimneys, whereas the combination of a hot hydrothermal fluid and cold ocean simulant inhibited the formation of robust chimney structures. The customizable 3D printed condenser created for this study acts as a jacketed reaction vessel that can be easily modified and used by different researchers. It will allow the careful control of injection rate and chemical composition of vent and ocean simulants, which should help accurately simulate prebiotic reactions in chimney systems with thermal gradients similar to those of natural systems.

The goal of this protocol is to form simulated hydrothermal chimneys via chemical garden injection experiments and introduce a thermal gradient across the inorganic precipitate membrane, using a 3D printable condenser that can be reproduced for educational purposes.

热梯度环境中早期地球热液烟囱的模拟

Deep sea hydrothermal vents are self-organizing precipitates generated from geochemical disequilibria and have been proposed as a possible setting for the ...

A Novel Bioreactor for High Density Cultivation of Diverse Microbial Communities

A novel reactor design, coined a high density bioreactor (HDBR), is presented for the cultivation and study of high density microbial communities. Past studies have evaluated the performance of the reactor for the removal of COD1 and nitrogen species2-4 by heterotrophic and chemoautotrophic bacteria, respectively. The HDBR design eliminates the requirement for external flocculation/sedimentation processes while still yielding effluent containing low suspended solids. In this study, the HDBR is applied as a photobioreactor (PBR) in order to characterize the nitrogen removal characteristics of an algae-based photosynthetic microbial community. As previously reported for this HDBR design, a stable biomass zone was established with a clear delineation between the biologically active portion of the reactor and the recycling reactor fluid, which resulted in a low suspended solid effluent. The algal community in the HDBR was observed to remove 18.4% of total nitrogen species in the influent. Varying NH4+ and NO3- concentrations in the feed did not have an effect on NH4+ removal (n=44, p=0.993 and n=44, p=0.610 respectively) while NH4+ feed concentration was found to be negatively related with NO3- removal (n=44, p=0.000) and NO3- feed concentration was found to be positively correlated with NO3- removal (n=44, p=0.000). Consistent removal of NH4+, combined with the accumulation of oxidized nitrogen species at high NH4+ fluxes indicates the presence of ammonia- and nitrite-oxidizing bacteria within the microbial community.

A novel reactor design, coined a high density bioreactor (HDBR), is presented for the cultivation and study of high density microbial communities. Here, the HDBR is successfully applied in a photobioreactor (PBR) configuration for the study of nitrogen metabolism by a mixed high density algal community.

一种新型生物反应器为不同的微生物群落的高密度栽培

A novel reactor design, coined a high density bioreactor (HDBR), is presented for the cultivation and study of high density microbial communities. Past ...

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

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

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

使用柔性金钛反应细胞在地下生物采矿环境中模拟压力依赖微生物活性

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

工程学

Mesocosm-Scale Constructed Wetland Design for Wastewater Treatment

Oil sands process-affected water (OSPW), a by-product of bitumen extraction through surface mining in Alberta, Canada, contains various constituents of concern, including naphthenic acid fraction compounds (NAFCs). These organic compounds are particularly worrisome due to their toxicity and persistence in the environment. Constructed wetland treatment systems (CWTS) use plants and their associated microbes to attenuate contaminants in wastewater. Field-scale CWTS have been presented as a potential large-scale treatment option for OSPW, specifically for degrading NAFCs. To optimize the use of CWTS for large-scale treatment of NAFCs in OSPW, it is essential to deepen our understanding of various design parameters and explore ways to enhance efficacy.
Mesocosm-scale experiments serve as a valuable intermediary, bridging the gap between complex field trials and controlled laboratory settings. Mesocosms provide a controlled, replicable environment to study the effects of various parameters such as substrate, plant species, temperature, and retention time while incorporating ecological complexities in their design. Published and previous work has shown that this method is successful in evaluating the impacts of different parameters on the efficacy of CWTS to attenuate NAFCs in OSPW. This protocol outlines the design and setup of a surface flow wetland mesocosm, along with the experimental approach for treating NAFCs in OSPW. This method can be adapted to treat other wastewaters across diverse geographical locations.

Constructed wetland treatment systems have been used for decades to treat wastewater, but their application to treat oil sands process-affected waters is relatively new. To explore this potential, a surface flow mesocosm design and experimental methods are outlined. This approach aims to enhance our understanding of key design parameters and improve treatment efficacy.

用于废水处理的中宇宙尺度人工湿地设计

Oil sands process-affected water (OSPW), a by-product of bitumen extraction through surface mining in Alberta, Canada, contains various constituents of ...

Window on a Microworld: Simple Microfluidic Systems for Studying Microbial Transport in Porous Media

Microbial growth and transport in porous media have important implications for the quality of groundwater and surface water, the recycling of nutrients in the environment, as well as directly for the transmission of pathogens to drinking water supplies. Natural porous media is composed of an intricate physical topology, varied surface chemistries, dynamic gradients of nutrients and electron acceptors, and a patchy distribution of microbes. These features vary substantially over a length scale of microns, making the results of macro-scale investigations of microbial transport difficult to interpret, and the validation of mechanistic models challenging. Here we demonstrate how simple microfluidic devices can be used to visualize microbial interactions with micro-structured habitats, to identify key processes influencing the observed phenomena, and to systematically validate predictive models. Simple, easy-to-use flow cells were constructed out of the transparent, biocompatible and oxygen-permeable material poly(dimethyl siloxane). Standard methods of photolithography were used to make micro-structured masters, and replica molding was used to cast micro-structured flow cells from the masters. The physical design of the flow cell chamber is adaptable to the experimental requirements: microchannels can vary from simple linear connections to complex topologies with feature sizes as small as 2 &mu;m. Our modular EcoChip flow cell array features dozens of identical chambers and flow control by a gravity-driven flow module. We demonstrate that through use of EcoChip devices, physical structures and pressure heads can be held constant or varied systematically while the influence of surface chemistry, fluid properties, or the characteristics of the microbial population is investigated. Through transport experiments using a non-pathogenic, green fluorescent protein-expressing Vibrio bacterial strain, we illustrate the importance of habitat structure, flow conditions, and inoculums size on fundamental transport phenomena, and with real-time particle-scale observations, demonstrate that microfluidics offer a compelling view of a hidden world.

Microfluidic devices can be used to visualize complex natural processes in real time and at the appropriate physical scales. We have developed a simple microfluidic device that mimics key features of natural porous media for studying growth and transport of bacteria in the subsurface.

窗口上的一个微观世界：简单的微流体系统为研究多孔介质中的微生物运输

Microbial growth and transport in porous media have important implications for the quality of groundwater and surface water, the recycling of nutrients in ...