The authors are grateful for the financial support provided by Instituto Polit&#233;cnico Nacional grants 20120110, 20130399 and 20140239 SIP and also by Instituto de Ciencia y Tecnolog&#237;a del Distrito Federal Mexico (PICS 08-79, ICYT-DF, 2009-2012). Thanks also to CONACYT &#8211; Mexico for the graduate scholarship (225806) awarded to Selene Montserrat Garc&#237;a-Solares and for the financial support provided by grant 82627.

<img alt="图1" src="/files/ftp_upload/52956/52956fig1highres.jpg" width="450" /> 图1.方案协议的步骤。 <a href="https://www.jove.com/files/ftp_upload/52956/52956fig1large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> 1.收集海洋沉积物对污泥的形成<ol><li>确定一个平易近人海底区域或者靠近热液喷口（由于硫化物的存在下，这可能表明较高的硫酸盐还原活性），或者一个区域，其中的有机物质碎片是可检测的。 </li><li>对于这项工作的目的，需要约3或4千克沉积物和漏水关样品。是在暗塑料袋样品。无需进行制冷。 </li><li>一旦在实验室中，保持与样品袋在冰箱，如果他们不打算立即使用。对于这项工作，桑普的目的LES可在冰箱几个星期或几个月使用它们之前。 </li><li>取沉积物样品（即1或2公斤）的很大一部分，并使用适当的筛目（0.2厘米）从沉积物中的大碎片含碳材料可被发现或一些岩石可能存在消除。 注意：在这种情况下0.20厘米直径（在0.0767）的网眼被用于，但它可以根据样品中的颗粒的尺寸是不同的尺寸。 <ol><li>传递沉积物通过网后，混合选择，以促进该部分是均匀的部分。 </li><li>取分离更小的样品（即，2至3克）通过以下的标准方法11，以确定挥发性悬浮固体（VSS）的内容。 注： 参见图2步骤1.2至1.4。 </li></ol></li></ol><img alt="图2" src="/files/ftp_upload/52956/52956fig2.jpg" /> 图2.照片中的沉积物样品。（一）沉积物样品刚过上当受骗。（B）沉积物样品通过网格后。（C）样品采取称重之前，挥发性悬浮固体（VSS）的决心。在培养皿中不需要进行消毒。 <a href="https://www.jove.com/files/ftp_upload/52956/52956fig2large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> 2.生物反应器设置<ol><li>对于这项工作的目的，使用的UASB反应器中的玻璃带3 L的总工作容积或者，使用1或2升容积玻璃反应器中。 </li><li>基于所述沉积物的VSS含量计算沉降物的数量被用作接种物，得到5克的VSS在1升</li><li>考虑到，如果沉积物计算后的量太大时，生物反应器的再约25％至30％的体积应当由沉积物代替占据。 <ol><li>记录，因为它的VSS内容将改变时，微生物群落富集的生物反应器。需要在VSS含量为硫酸盐的计算降低生物反应器中的活性。 </li></ol></li><li>确保生物反应器中的基础培养基和缓冲溶液的最终浓度是类似于所报告的格雷罗哈斯等 。 （2014）12。 <ol><li>确保沉积物，基本培养基，缓冲溶液和挥发性脂肪酸的最终体积是等于反应器中的最终工作体积。基础培养基配方12含有适当浓度的痕量金属和维生素溶液。 </li><li>制备基础培养基和缓冲液的储备溶液在适当的浓度为反应器所用的工作体积（即，2，3或4倍比报道的步骤2.4更浓缩的），以确保当它被稀释，它是在报告的格雷罗-巴拉哈斯等的浓度。 （2014年）12）。 注意：储备溶液的基础培养基是总是必要的，然而，缓冲溶液时，才需要在启动时。它没有必要在此时间后添加缓冲溶液。 </li><li>制备的挥发性脂肪酸的原液：在2.5乙酸盐，丙酸盐和丁酸盐：1：1比例的COD。考虑到为计算的乙酸钠包括在基础培养基。在反应器中的最终的COD浓度必须2.7克/升。 注意：准备这个解决方案在通风橱中。穿腈手套和护目镜此溶液的制备。考虑到硫酸与挥发性脂肪酸的反应， 示于图3的化学计量。 </li><li>制备的硫酸钠在适当浓度的储备溶液（ 用 Na 2 SO 4），可提供到反应器中的4000毫克/升的硫酸根离子（SO 4 2-）的终浓度。可替代地，包括第硫酸盐在基础培养基所需的，而不是只要由一个储液加入其作为最终硫酸盐电子量（SO 4 2-）的浓度是合适的。 </li></ol></li><li>放置在反应器中与基础培养基的一部分混合，沉积物，以确保它们到达反应器的底部。 <ol><li>添加与挥发性脂肪酸溶液和硫酸溶液混合的基础培养基和缓冲溶液的其余部分。确保的挥发性脂肪酸的溶液倒入液体。注意：进行这个步骤在通风橱中。 </li><li>设置的连接和该反应器的管道，以再循环泵。设定再循环流速为60毫升/分钟。在34°C在设定温度室的生物反应器。定期检查温度变化小（ 即 34±1.7°C） </li><li>设置连接到气体位移列。 注： 参见图4的步骤2.1至2.5。 </li> &lt;/ OL&gt; </li></ol><img alt="图3" src="/files/ftp_upload/52956/52956fig3highres.jpg" width="600" /> 图3.化学计量硫酸盐还原VFA（乙酸，丙酸和丁酸）的。 <a href="https://www.jove.com/files/ftp_upload/52956/52956fig3large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图4" src="/files/ftp_upload/52956/52956fig4highres.jpg" width="400" /> 图4. UASB反应器。（A）初始时间。（B）连续政权在300天的运行中。 <a href="https://www.jove.com/files/ftp_upload/52956/52956fig4large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> 3.操作反应器的促进Sulfidogenesis微生物和生长注意：允许用于接种物消​​耗购买Volatile脂肪酸和硫酸。为了这个目的，等待一个星期进行为硫酸盐，硫化物和COD消耗首次分析。 <ol><li>后孵育1周采取的5至7毫升液体的样品进行分析，化学需氧量，硫酸盐和硫化物含量和pH下述标准方法11,13。 <ol><li>通过以下亚甲蓝方法13分析硫化物在液体分光光度计（在670纳米的波长（λ））。 <ol><li>放置5毫升乙酸锌溶液（2％w / w的）在25毫升容量瓶中，加迅速加入200μl样品到醋酸锌溶液。 </li><li>加入2.5毫升N，N-二甲基对苯二胺草酸（DMP）溶液（0.2％w / w的20％ 的 H 2 SO 4）和125微升铁（III）硫酸铵溶液（10％重量/的瓦特在2％的H 2 SO 4）并完成与蒸馏水25毫升的容量瓶中。等待30分钟的反应发生，时间在其中蓝色颜色是稳定的。13。 注：等待至少15分钟，但不超过60分钟，以测试样品中的分光光度计。进行在分光光度计蓝色最终溶液的读数。 </li></ol></li><li>根据标准方法11分析干燥。这里，通过使用比浊法量化硫酸硫酸钡。 <ol><li>放置5毫升的调理溶液（盐酸盐酸1：1）在25毫升容量瓶中，加入1毫升先前离心样品（在11320×g）中，完成将25ml量瓶中，用蒸馏水和加1克氯化钡。 </li><li>混合在一涡旋1分钟的溶液中。等待4分钟的硫酸钡，以形成与读取在分光光度计的样品在420纳米11一个波长（λ）。 </li></ol></li><li>根据标准方法分析11的COD。或者，使用COD Determina的化套件。 <ol><li>在此之前的COD测定，彻底离心样品（在11320 XG）除去剩余的硫化物，可能会干扰测定。如果需要的话，离心两次：第一次立即服用样品和第二时间之后等待6或8小时，然后进行分析的COD。 </li><li>加2ml样品与COD测定试剂盒的反应小瓶中，密封该小瓶并均化通过温和搅拌该混合物。制备一个空白加入2毫升蒸馏水至另一个反应瓶中并均化混合物。 </li><li>放置在消化反应器中的小瓶，在150℃进行2小时。取出小瓶，让他们在黑暗中冷却下来。采取在分光光度计小瓶的读数在620纳米的波长。 </li></ol></li><li>获得从气体置换柱的气体体积。 </li></ol></li><li>最多等待另一个5到7天，直到硫酸的消耗。硫酸和COD必须在被消耗前pproximately 85％至90％，开始一个新的补料分批。 </li><li>一旦硫酸（和COD）的消耗，完全重复步骤2.4。供应新鲜培养基和营养物的新为每批次。 </li><li>重复步骤3.1和3.2。在这一点上每批次之间应该7天和10天持续。 </li><li>当3〜4批已全部完成，重复步骤2.4，但会增加COD浓度为4克/升。 </li><li>重复步骤3.1和3.2的步骤。 <ol><li>重复步骤3.3，但增加的COD浓度，以6克/升。 </li><li>重复3.6和3.6.1逐渐增加COD浓度，直到它为10克/升。 注意：请呈现硫酸浓度（mg / L）与时间（d）该曲线图。 </li></ol></li><li>当硫酸盐消耗量是80％以上，不到24小时，出现这种情况的一个多星期，开关在反应器的操作，以连续模式。对于连续模式中设置的水力停留时间（HRT），在24小时，并保持硫酸盐浓度在4克/升和COD的以10克/升。 注：随着时间的推移硫酸盐消费量应 速度更快。 </li></ol> 4.硫酸盐还原活性测试<ol><li>在此之前，测试确保连续制度下，生物反应器呈现在硫酸盐浓度剩余小于10％的变化。 </li><li>在任何给定的一天后，其中HRT周期和行为的步骤2.4停止反应器。对于步2.4.3用10克/升的COD浓度。 </li><li>一旦在生物反应器被供给，需要5到7 ml的样品的液体和化学需氧量，硫酸盐，硫化物（步骤3.1）和pH每小时执行分析。记录产生的气体量。 </li><li>计算硫酸根据文献14还原活性。 <img alt="式（1）" src="/files/ftp_upload/52956/52956eq1.jpg" /></li></ol> SRA =硫酸盐还原活性（毫克COD-H 2 S）/ gVSS量* D 米H 2 </em&gt; S =硫化物浓度单位为mg COD-H 2 S VSS =挥发性悬浮固体浓度 T =时间（D或小时） <ol start="5"><li>作出这样的显示硫酸盐消耗量与硫化物浓度的百分比随时间以mg / L对应的图形。使该显示的COD消耗随时间的百分比的曲线图。制作，显示随着时间的推移pH值变化的曲线图。 </li></ol> 5，三氯乙烯（TCE）还原试验<ol start="1"><li>在此之前，测试确保生物反应器正在连续制度下，并提出在硫酸盐浓度剩余小于10％的变化。不启动此测试如果硫酸盐还原生物反应器中低于90％。 </li><li>制备的三氯乙烯考虑到在生物反应器的液相中该化合物的最终浓度必须为300微米的储备液（TCE）。考虑partitioniNG使用Henry&#39;s法因次常数（H&#39;）的TCE在34°C的化合物的顶空。 H&#39;at 34℃，TCE为0.4722。 <img alt="公式（2）" src="/files/ftp_upload/52956/52956eq2.jpg" /> 注意：准备这个解决方案在通风柜和戴手套和护目镜。 <ol><li>例如，对于一个5000微米原液，计算如下： <img alt="公式3" src="/files/ftp_upload/52956/52956eq3.jpg" /> TCE气相浓度=（0.4722）*（5000）= 2139微米。包括这个浓度，因为这一数额TCE将是在顶空原液的制备。 然后，在原液中的液体（水），实际的TCE的浓度将是：5000 + 2139 = 7139μM。 TCE密度=1.43克/毫升。转换7139微米为mg，然后通过使用三氯乙烯的密度计算的TCE为原液的体积。 注：的TCE原液米浓度唉低于5000微米， 即 3000或1000微米，这取决于如何将该溶液的体积太大，根据其液相体积可以被传递至生物反应器。 </li></ol></li><li>制备标准曲线，在气相色谱仪的三氯乙烯， 顺 -1,2-二氯乙烯， 反式 -1,2-二氯乙烯，氯乙烯和乙烯。通过以下在5.2的三氯乙烯原液描述的相同方法制备的顺式 -1,2-二氯乙烯，反式-1,2-二氯乙烯的标准曲线从这些化合物的贮备液。通过从标准（气瓶）稀释每种气体的浓度制备氯乙烯和乙烯的标准曲线。 <ol><li>制备这些化合物的标准曲线的范围内的20至300微米。使用报告格雷罗-巴拉哈斯等人的方法 。 （2011）15，用于这些化合物在气相色谱仪的分析。 注意：这些准备站在通风柜ARD解决方案，并戴上手套和护目镜。 </li></ol></li><li>在任何给定的一天后，其中HRT周期和行为的步骤2.4停止反应器。对于步2.4.3用10克/升的COD浓度。 </li><li>一旦在生物反应器被供给，直接添加到三氯乙烯中的液体从在5.2制备的原液的生物反应器，生物反应器中的液相中的最终的TCE浓度必须为300μm。水力停留时间设定为12小时。 <ol><li>在一个HRT周期结束取液（500〜1000微升）和行为分析的COD，硫酸盐和硫化物的样品（步骤3.1.1，3.1.2和3.1.3）。取的顶部空间（100〜250微升）的样品，并进行分析，三氯乙烯，顺-1,2-二氯乙烯， 反式 -1,2-二氯乙烯，氯乙烯和乙烯在气相色谱仪。 </li></ol></li><li>重复步骤2.4。对于步2.4.3用10克/升的COD浓度。 </li><li>不要重复任何TCE还原试验，直到生物反应器中呈现超过900硫酸盐0％减少和较少的10％的变化两者，硫酸盐还原和硫酸中剩余的生物反应器。 </li><li>重复5.4，5.5和5.6两三次以上。 </li><li>取沉积物样品（0.5克）只需经过TCE减少测试完成后进行鉴定微生物。经过2或3 TCE减少测试执行此操作。 </li></ol> 6.硫酸盐还原TCE实验后还原活性测试<ol start="1"><li>完全重复步骤4。 </li></ol> 7.鉴定微生物<ol><li>取各得到大约0.5g污泥样品，并按照标准方法进行12总RNA提取。 </li><li>扩增16S rRNA基因用反转录，并进行聚合酶链反应（RT-PCR）扩增一个步骤12。 </li><li>设计引物扩增或作为初始的方法使用那些在文学11建议。按照amplif在文学12 ication程序建议。 </li><li>构建的16S rRNA库。 PCR扩增子可以通过使用克隆杰11被克隆。通常情况下，从各板（各菌落代表一个PCR产物）10个菌落可以克隆。根据在文献12提出的程序制备的质粒DNA进行测序。 </li><li>进行片段的测序。根据在文献中12建议的程序重新扩增大约1400 bp的对PCR外部产物与先前描述的方案进行PCR扩增（步骤7.4）和克隆。隔离来自大肠杆菌的质粒大肠杆菌菌落如文献12建议。不要进行部分程序进行测序应用M13通用引物12。 </li><li>进行序列分析。通过使用Clustal X对齐的核苷酸序列，并在文本编辑器中手动调整。执行NCBI databas的BLAST搜索即（http://www.ncbi.nlm.nih.gov/BLAST/Blast.cgi）12。 </li><li>得到的核苷酸序列的登录号。沉积下的对应登录号（即，JQ713915eJQ713925从扩增子序列）12确定在EMBL核苷酸序列数据库（根银行/ EMBL / DDBJ） ​​克隆的核苷酸序列。 </li></ol>

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H., Inagaki, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dehalogenation+activities+and+distribution+of+reductive+dehalogenase+homologous+genes+in+marine+subsurface+sediments.">Dehalogenation activities and distribution of reductive dehalogenase homologous genes in marine subsurface sediments.</a> Applied and Environmental Microbiology. 75 (21), 6905-6909 (2009).</li><li>U.S. Environmental Protection Agency. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=List+of+priority+pollutants.">List of priority pollutants.</a> Clean Water Methods. , (2014).</li><li>Ozdemir, C., Dursun, S., Karatas, M., Sen, N., Sahinkaya, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Removal+of+trichloroethylene+(TCE)+in+upFlow+anaerobic+sludge+blanket+reactors+(UASB).">Removal of trichloroethylene (TCE) in upFlow anaerobic sludge blanket reactors (UASB).</a> Biotechnology and Biotechnological Equipment. 21 (1), 107-112 (2007).</li><li>Zhang, Y., Wang, X., Hu, M., Li, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+hydraulic+retention+time+(HRT)+on+the+biodegradation+of+trichloroethylene+wastewater+and+anaerobic+bacterial+community+in+the+UASB+reactor.">Effect of hydraulic retention time (HRT) on the biodegradation of trichloroethylene wastewater and anaerobic bacterial community in the UASB reactor.</a> Applied Microbiology and Biotechnology. 99, 1977-1987 (2015).</li><li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Standard Methods for the Examination of Water and Wastewater. , (1998).</li><li>Guerrero-Barajas, C., 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=Enhanced+sulfate+reduction+and+trichloroethylene+(TCE)+biodegradation+in+a+UASB+reactor+operated+with+sludge+developed+from+hydrothermal+vents+sediments:+process+and+microbial+ecology.">Enhanced sulfate reduction and trichloroethylene (TCE) biodegradation in a UASB reactor operated with sludge developed from hydrothermal vents sediments: process and microbial ecology.</a> International Biodeterioration and Biodegradation. 94, 182-191 (2014).</li><li>Tr&#252;per, H. G., Schlegel, H. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sulphur+metabolism+in+Thiorhodaceae+I.+Quantitative+measurements+on+growing+cells+of+Chromatium+okenii.">Sulphur metabolism in Thiorhodaceae I. Quantitative measurements on growing cells of Chromatium okenii.</a> Antoine van Leeuwenhoek. 30, 225-238 (1964).</li><li>Gallegos-Garc&#237;a, M. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Biological processes of sulfate reduction in biofilms for metals precipitation [Ph D thesis]. , (2009).</li><li>Guerrero-Barajas, C., Garibay-Orijel, C., Rosas-Rocha, L. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sulfate+reduction+and+trichloroethylene+biodegradation+by+a+marine+microbial+community+from+hydrothermal+vents+sediments.">Sulfate reduction and trichloroethylene biodegradation by a marine microbial community from hydrothermal vents sediments.</a> International Biodeterioration and Biodegradation. 65, 116-123 (2011).</li></ol>

The authors Selene Montserrat Garc&#237;a-Solares, Claudio Garibay-Orijel and Claudia Guerrero Barajas submitted (as inventors) in 2012 the application to obtain a patent entitled: &#8220;Process for the anaerobic treatment of industrial wastewater with high content of sulfate and chlorinated compounds&#8221;. This submission has been approved to the stage of the formatting. The submission has Instituto Polit&#233;cnico Nacional as the rights owner.

有sulfidogenesis的环境生物技术多个应用程序，硫酸盐还原细菌的代谢的最常用的应用程序在财团与发酵菌是在废水处理中的一个。 UASB反应器是主要的设计方法，以工业废水处理与硫酸盐高浓度之间。在这项工作中，我们提出了一个协议，以获得从海洋沉积物sulfidogenic污泥的UASB反应器。在协议中的关键步骤，以从海洋沉积物获得sulfidogenic污泥是：（1）促进沉积物样品的的同源被放置在反应器中，?...

一对环境生物技术的最重要的贡献是生物反应器，其中使用（接种物）的污泥能够硫酸盐还原条件下进行的设计。硫酸盐还原（SR）允许含有除同时除去COD，重金属和有机污染物，这一事实使SR中的污泥1的期望特性的高浓度硫酸的废水流的治疗。废水污染硫酸的一些例子来自制革，造纸，医药，化工等制造行业1。然而，大多数的文献是指sulfidogenic污泥时产甲烷颗粒污泥已适应sulfidogenesis 2。这种适应是通过操纵COD / SO 4 2-比在生物反应器和添加的化学品，以抑制在污泥2,3甲烷通常达到。除了长的时间是m唉要求sulfidogenic颗粒的形成中，甲烷和硫酸盐还原和污泥的高浓度硫化物的公差之间的竞争，是一些主要问题，如果是从适应获得在生物反应器中使用的sulfidogenic污泥可能出现主要产甲烷污泥硫酸盐还原条件。在这项工作中，我们描述的方法在上流式厌氧污泥床反应器（UASB），以获得从热液喷口沉积物（蓬美达，纳亚里特，墨西哥）主要为sulfidogenic污泥，然后我们评估它的硫酸盐还原活性随着时间的推移，进行了一个实验以评估其对还原脱氯的应用。被选择的沉积物的位置，因为它已被报道，在该网站有形成硫化物由于通过微生物群落栖息该特定地方4呈现的硫酸盐还原活性。 有SEVER人的优势获得沉积物这sulfidogenic污泥在适应产甲烷颗粒污泥sulfidogenesis。其中的一些优点是：（1）这是没有必要以形成颗粒的生物反应器进行操作，（2）将污泥容忍较高浓度硫化物的相比更为UASB与适于甲烷污泥操作，和（3）有用即使乙酸的用量为包含在培养基中以促进污泥的形成挥发性脂肪酸的混合物甲烷为基片没有竞争。 此步骤，以促进sulfidogenesis因为海洋沉积物有各种各样，如硫酸盐还原菌，发酵菌和细菌脱卤，只是仅举几例5,6微生物的天然泳池。财团从海洋沉积物开发利用这一协议的类型可能会出现在硫酸盐还原，因此，高的工作效率<html> ulfate还原活性随着时间的推移和更高的耐受性硫化物的浓度比报告为有毒的产甲烷菌和硫酸盐还原菌更高。另一方面，它很可能是该脱卤能力由以下此处协议提议的，但它可以取决于原始微生物群落也示于沉积物。这种假设是基于这样还原脱氯可以通过呼吸或共代谢发生的事实完成的，这两个条件，可能会在海洋微生物群落7得到提升。沉积物以获得污泥的培养物通过使用乙酸盐，丙酸盐和丁酸盐的混合物作为底物，因为这些挥发性脂肪酸所使用的几株硫酸盐还原细菌的进行。这些酸也经常发现在海洋沉积物碳化合物的种类，根据在文献中关于碳质材料在海沉积物5,6-若干报告。 内容“&gt;最后，一些被发现在地下水和其他水体，世界各地的最有毒化合物是氯化溶剂，如三氯乙烯（TCE）或全氯乙烯（PCE）。这些化合物是有毒的，不仅对人，而是还对微生物，特别是三氯乙烯，这仍然是在美国被认为是优先的污染物由环境保护局8。在这项工作中，我们提出，是在一个实验，其中sulfidogenic污泥减少TCE浓度的其能力进行测试系列报道的甲烷条件下，9,10含氯化合物生物降解性。值得一提的是，大多数的含氯化合物的生物降解研究已经甲烷条件9,10下进行的。我们认为，实验TCE在该协议提出的是一个的污泥的潜在应用很好的例子。该实验的目的是到e计价污泥的三氯乙烯和对硫酸盐还原活性的三氯乙烯效果的耐受性。考虑到最上氯化化合物的生物降解研究的是甲烷条件下进行的，该协议建议一个油泥的产生可以被用来同时：（1）除去硫酸，（2）除去COD和（3）除去氯化合物。进一步的步骤可以是评价对同时除去三氯乙烯和重金属的污泥（除了硫酸盐和COD），这是不能被甲烷条件下评价两个条件。

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>trichloroethylene&#160;</td>
			<td>sigma Aldrich</td>
			<td align="right">251402</td>
			<td></td>
		</tr>
		<tr>
			<td>cis- 1,2 dichlorotehylene</td>
			<td>sigma Aldrich</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>trans-1,2 dichloroethylene</td>
			<td>sigma Aldrich</td>
			<td>D-62209</td>
			<td></td>
		</tr>
		<tr>
			<td>vinyl chloride scotty standard</td>
			<td>supelco</td>
			<td></td>
			<td>1000 ppm v/v in nitrogen</td>
		</tr>
		<tr>
			<td>ethene scotty standard</td>
			<td>supelco</td>
			<td></td>
			<td>99% purity</td>
		</tr>
		<tr>
			<td>pump</td>
			<td>Masterflex</td>
			<td></td>
			<td>Model 7553-75</td>
		</tr>
		<tr>
			<td>spectrophotometer</td>
			<td>any</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>microcentrifuge</td>
			<td>any</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>gas tight syringes&#160;</td>
			<td>any</td>
			<td></td>
			<td>100 and 200 microliters</td>
		</tr>
		<tr>
			<td>UASB glass reactor</td>
			<td>any</td>
			<td></td>
			<td>under design</td>
		</tr>
		<tr>
			<td>gas chromatograph&#160;</td>
			<td>any</td>
			<td></td>
			<td>FID detector</td>
		</tr>
		<tr>
			<td>capillary column SPB-624</td>
			<td>supelco</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>pH meter</td>
			<td>any</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>viton tubing</td>
			<td>Masterflex</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>basal medium reagents</td>
			<td>any</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>trace metals reagents</td>
			<td>any</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>vitamins solution reagents</td>
			<td>any</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>sodium sulfate</td>
			<td>any</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>volatile fatty acids</td>
			<td>any</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>COD determination kit</td>
			<td>HACH</td>
			<td></td>
			<td>range 0-15000 mg/L</td>
		</tr>
		<tr>
			<td>TOPO-TA cloning kit pCR&#174;4.0&#160;</td>
			<td>Invitrogen, US</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>S.N.A.P. TM Miniprep Kit&#160;</td>
			<td>Invitrogen, UK</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Pure link TM Quick Plasmid Miniprep kit</td>
			<td>Invitrogen</td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

development of sulfidogenic sludge from marine sediments and trichloroethylene reduction in an upflow anaerobic sludge blanket reactor

The importance of microbial sulfate reduction relies on the various applications that it offers in environmental biotechnology. Engineered sulfate reduction is used in industrial wastewater treatment to remove large concentrations of sulfate along with the chemical oxygen demand (COD) and heavy metals. The most common approach to the process is with anaerobic bioreactors in which sulfidogenic sludge is obtained through adaptation of predominantly methanogenic granular sludge to sulfidogenesis. This process may take a long time and does not always eliminate the competition for substrate due to the presence of methanogens in the sludge. In this work, we propose a novel approach to obtain sulfidogenic sludge in which hydrothermal vents sediments are the original source of microorganisms. The microbial community developed in the presence of sulfate and volatile fatty acids is wide enough to sustain sulfate reduction over a long period of time without exhibiting inhibition due to sulfide. 
This protocol describes the procedure to generate the sludge from the sediments in an upflow anaerobic sludge blanket (UASB) type of reactor. Furthermore, the protocol presents the procedure to demonstrate the capability of the sludge to remove by reductive dechlorination a model of a highly toxic organic pollutant such as trichloroethylene (TCE). The protocol is divided in three stages: (1) the formation of the sludge and the determination of its sulfate reducing activity in the UASB, (2) the experiment to remove the TCE by the sludge, and (3) the identification of microorganisms in the sludge after the TCE reduction. Although in this case the sediments were taken from a site located in Mexico, the generation of a sulfidogenic sludge by using this procedure may work if a different source of sediments is taken since marine sediments are a natural pool of microorganisms that may be enriched in sulfate reducing bacteria.

的生物反应器中硫酸盐还原的典型行为示于图5。注意到，在硫酸操作减少第一周将是缓慢的是很重要的。然而慢，硫酸随时间的90％以上的消耗表明接种物正在开发的微生物群落能够减少干燥并因此，富含硫酸盐还原菌。图中的不同时期表明，硫酸盐还原反应增加其速度随时间。在开始时，批料用了20天的硫酸将减少（期间I）中，那么它的降低率正在增加，这需要大约10?...

Watch this Scientific Journal Video about Development of Sulfidogenic Sludge from Marine Sediments and Trichloroethylene Reduction in an Upflow Anaerobic Sludge Blanket Reactor at JoVE.com

Development of Sulfidogenic Sludge from Marine Sediments and Trichloroethylene Reduction in an Upflow Anaerobic Sludge Blanket Reactor

Microbial sulfate reduction is a process of great importance in environmental biotechnology. The success of the sulfidogenic reactors depends among other factors on the microbial composition of the sludge. Here, we present a protocol to develop sulfidogenic sludge from hydrothermal vents sediments in a UASB reactor for reductive dechlorination purposes.

Sulfidogenic污泥海洋沉积物和三氯乙烯减少在上流式厌氧污泥床反应器开发

The importance of microbial sulfate reduction relies on the various applications that it offers in environmental biotechnology. Engineered sulfate ...

development-sulfidogenic-sludge-from-marine-sediments

Research

JoVE Journal

Environment

9.6K 次观看.  Instituto Politécnico Nacional. Microbial sulfate reduction is a process of great importance in environmental biotechnology. The success of the sulfidogenic reactors depends among other factors on the microbial composition of the sludge. Here, we present a protocol to develop sulfidogenic sludge from hydrothermal vents sediments in a UASB reactor for reductive dechlorination purposes.

视频: Development of Sulfidogenic Sludge from Marine Sediments and Trichloroethylene Reduction in an Upflow Anaerobic Sludge Blanket Reactor

A Fish-feeding Laboratory Bioassay to Assess the Antipredatory Activity of Secondary Metabolites from the Tissues of Marine Organisms

Marine chemical ecology is a young discipline, having emerged from the collaboration of natural products chemists and marine ecologists in the 1980s with the goal of examining the ecological functions of secondary metabolites from the tissues of marine organisms. The result has been a progression of protocols that have increasingly refined the ecological relevance of the experimental approach. Here we present the most up-to-date version of a fish-feeding laboratory bioassay that enables investigators to assess the antipredatory activity of secondary metabolites from the tissues of marine organisms. Organic metabolites of all polarities are exhaustively extracted from the tissue of the target organism and reconstituted at natural concentrations in a nutritionally appropriate food matrix. Experimental food pellets are presented to a generalist predator in laboratory feeding assays to assess the antipredatory activity of the extract. The procedure described herein uses the bluehead, Thalassoma bifasciatum, to test the palatability of Caribbean marine invertebrates; however, the design may be readily adapted to other systems. Results obtained using this laboratory assay are an important prelude to field experiments that rely on the feeding responses of a full complement of potential predators. Additionally, this bioassay can be used to direct the isolation of feeding-deterrent metabolites through bioassay-guided fractionation. This feeding bioassay has advanced our understanding of the factors that control the distribution and abundance of marine invertebrates on Caribbean coral reefs and may inform investigations in diverse fields of inquiry, including pharmacology, biotechnology, and evolutionary ecology.

This bioassay employs a model predatory fish to assess the presence of feeding-deterrent metabolites from organic extracts of the tissues of marine organisms at natural concentrations using a nutritionally comparable food matrix.

了鱼喂食实验室生物测定，从海洋生物的组织评估次生代谢产物的Antipredatory活动

Marine chemical ecology is a young discipline, having emerged from the collaboration of natural products chemists and marine ecologists in the 1980s with ...

科研

环境科学

VacuSIP, an Improved InEx Method for In Situ Measurement of Particulate and Dissolved Compounds Processed by Active Suspension Feeders

Benthic suspension feeders play essential roles in the functioning of marine ecosystems. By filtering large volumes of water, removing plankton and detritus, and excreting particulate and dissolved compounds, they serve as important agents for benthic-pelagic coupling. Accurately measuring the compounds removed and excreted by suspension feeders (such as sponges, ascidians, polychaetes, bivalves) is crucial for the study of their physiology, metabolism, and feeding ecology, and is fundamental to determine the ecological relevance of the nutrient fluxes mediated by these organisms. However, the assessment of the rate by which suspension feeders process particulate and dissolved compounds in nature is restricted by the limitations of the currently available methodologies. Our goal was to develop a simple, reliable, and non-intrusive method that would allow clean and controlled water sampling from a specific point, such as the excurrent aperture of benthic suspension feeders, in situ. Our method allows simultaneous sampling of inhaled and exhaled water of the studied organism by using minute tubes installed on a custom-built manipulator device and carefully positioned inside the exhalant orifice of the sampled organism. Piercing a septum on the collecting vessel with a syringe needle attached to the distal end of each tube allows the external pressure to slowly force the sampled water into the vessel through the sampling tube. The slow and controlled sampling rate allows integrating the inherent patchiness in the water while ensuring contamination free sampling. We provide recommendations for the most suitable filtering devices, collection vessel, and storing procedures for the analyses of different particulate and dissolved compounds. The VacuSIP system offers a reliable method for the quantification of undisturbed suspension feeder metabolism in natural conditions that is cheap and easy to learn and apply to assess the physiology and functional role of filter feeders in different ecosystems.

VacuSIP, an Improved InEx Method for In Situ Measurement of Particulate and Dissolved Compounds Processed by Active Suspension Feeders

We introduce the VacuSIP, a simple, non-intrusive, and reliable method for clean and accurate point sampling of water. The system was developed and evaluated for the simultaneous collection of the water inhaled and exhaled by benthic suspension feeders in situ, to cleanly measure removal and excretion of particulate and dissolved compounds.

VacuSIP，对改进的方法INEX<em&gt;原位</em&gt;颗粒物与测量溶解的化合物加工后主动悬挂给料机

Benthic suspension feeders play essential roles in the functioning of marine ecosystems. By filtering large volumes of water, removing plankton and ...

Extraction of Structural Extracellular Polymeric Substances from Aerobic Granular Sludge

To evaluate and develop methodologies for the extraction of gel-forming extracellular polymeric substances (EPS), EPS from aerobic granular sludge (AGS) was extracted using six different methods (centrifugation, sonication, ethylenediaminetetraacetic acid (EDTA), formamide with sodium hydroxide (NaOH), formaldehyde with NaOH and sodium carbonate (Na2CO3) with heat and constant mixing). AGS was collected from a pilot wastewater treatment reactor. The ionic gel-forming property of the extracted EPS of the six different extraction methods was tested with calcium ions (Ca2+). From the six extraction methods used, only the Na2CO3 extraction could solubilize the hydrogel matrix of AGS. The alginate-like extracellular polymers (ALE) recovered with this method formed ionic gel beads with Ca2+. The Ca2+-ALE beads were stable in EDTA, formamide with NaOH and formaldehyde with NaOH, indicating that ALE are one part of the structural polymers in EPS. It is recommended to use an extraction method that combines physical and chemical treatment to solubilize AGS and extract structural EPS.

The protocol provides a methodology to solubilize aerobic granular sludge in order to extract alginate-like extracellular polymers (ALE).

从好氧颗粒污泥结构胞外聚合物的提取

To evaluate and develop methodologies for the extraction of gel-forming extracellular polymeric substances (EPS), EPS from aerobic granular sludge (AGS) ...

A Flow-through Exposure System for Evaluating Suspended Sediments Effects on Aquatic Life

This paper describes the Fish Larvae and Egg Exposure System (FLEES). The flow-through exposure system is used to investigate the effects of suspended sediment on various aquatic species and life stages in the laboratory by using pumps and automating delivery of sediment and water to simulate suspension of sediment. FLEES data are used to develop exposure-response curves between the effects on aquatic organisms and suspended sediment concentrations at the desired exposure duration. The effects data are used to evaluate management practices used to reduce the interactions between aquatic organisms and anthropogenic causes of suspended sediments. The FLEES is capable of generating total suspended solids (TSS) concentrations as low as 30 to as high as 800 mg/L, making this system an ideal choice for evaluating the effects of TSS resulting from many activities including simulating low ambient levels of TSS to evaluating sources of suspended sediments from dredging operations, vessel traffic, freshets, and storms.

A robust and flexible flow-through exposure system designed to maintain sediment in suspension is presented. The system is used to investigate the effects of suspended sediment on various aquatic species and life stages in the laboratory.

对水生生命值评价悬浮泥沙影响的流通系统曝光

This paper describes the Fish Larvae and Egg Exposure System (FLEES). The flow-through exposure system is used to investigate the effects of suspended ...

Preparation of Authigenic Pyrite from Methane-bearing Sediments for In Situ Sulfur Isotope Analysis Using SIMS

Different sulfur isotope compositions of authigenic pyrite typically result from the sulfate-driven anaerobic oxidation of methane (SO4-AOM) and organiclastic sulfate reduction (OSR) in marine sediments. However, unravelling the complex pyritization sequence is a challenge because of the coexistence of different sequentially formed pyrite phases. This manuscript describes a sample preparation procedure that enables the use of secondary ion mass spectroscopy (SIMS) to obtain in situ &#948;34S values of various pyrite generations. This allows researchers to constrain how SO4-AOM affects pyritization in methane-bearing sediments. SIMS analysis revealed an extreme range in &#948;34S values, spanning from -41.6 to +114.8&#8240;, which is much wider than the range of &#948;34S values obtained by the traditional bulk sulfur isotope analysis of the same samples. Pyrite in the shallow sediment mainly consists of 34S-depleted framboids, suggesting early diagenetic formation by OSR. Deeper in the sediment, more pyrite occurs as overgrowths and euhedral crystals, which display much higher SIMS &#948;34S values than the framboids. Such 34S-enriched pyrite is related to enhanced SO4-AOM at the sulfate-methane transition zone, postdating OSR. High-resolution in situ SIMS sulfur isotope analyses allow for the reconstruction of the pyritization processes, which cannot be resolved by bulk sulfur isotope analysis.

Preparation of Authigenic Pyrite from Methane-bearing Sediments for In Situ Sulfur Isotope Analysis Using SIMS

Analyses of the sulfur isotopic composition (&#948;34S) of pyrite from methane-bearing sediments have typically focused on bulk samples. Here, we applied secondary ion mass spectroscopy to analyze the &#948;34S values of various pyrite generations to understand the diagenetic history of pyritization.

原位含甲烷沉积物中自黄铁矿的制备及应用模拟器硫同位素分析

Different sulfur isotope compositions of authigenic pyrite typically result from the sulfate-driven anaerobic oxidation of methane (SO4-AOM) and ...

Development of New Methods for Quantifying Fish Density Using Underwater Stereo-video Tools

The use of video camera systems in ecological studies of fish continues to gain traction as a viable, non-extractive method of measuring fish lengths and estimating fish abundance. We developed and implemented a rotating stereo-video camera tool that covers a full 360 degrees of sampling, which maximizes sampling effort compared to stationary camera tools. A variety of studies have detailed the ability of static, stereo-camera systems to obtain highly accurate and precise measurements of fish; the focus here was on the development of methodological approaches to quantify fish density using rotating camera systems. The first approach was to develop a modification of the metric MaxN, which typically is a conservative count of the minimum number of fish observed on a given camera survey. We redefine MaxN to be the maximum number of fish observed in any given rotation of the camera system. When precautions are taken to avoid double counting, this method for MaxN may more accurately reflect true abundance than that obtained from a fixed camera. Secondly, because stereo-video allows fish to be mapped in three-dimensional space, precise estimates of the distance-from-camera can be obtained for each fish. By using the 95% percentile of the observed distance from camera to establish species-specific areas surveyed, we account for differences in detectability among species while avoiding diluting density estimates by using the maximum distance a species was observed. Accounting for this range of detectability is critical to accurately estimate fish abundances. This methodology will facilitate the integration of rotating stereo-video tools in both applied science and management contexts.

We describe a new method for counting fishes, and estimating relative abundance (MaxN) and fish density using rotating stereo-video camera systems. We also demonstrate how to use distance from camera (Z distance) to estimate species-specific detectability.

利用水下立体视频工具量化鱼类密度的新方法研究进展

The use of video camera systems in ecological studies of fish continues to gain traction as a viable, non-extractive method of measuring fish lengths and ...

An Ultra-clean Multilayer Apparatus for Collecting Size Fractionated Marine Plankton and Suspended Particles

The distributions of many trace elements in the ocean are strongly associated with the growth, death, and re-mineralization of marine plankton and those of suspended/sinking particles. Here, we present an all plastic (Polypropylene and Polycarbonate), multi-layer filtration system for collection of suspended particulate matter (SPM) at sea. This ultra-clean sampling device has been designed and developed specifically for trace element studies. Meticulous selection of all non-metallic materials and utilization of an in-line flow-through procedure minimizes any possible metal contamination during sampling. This system has been successfully tested and tweaked for determining trace metals (e.g., Fe, Al, Mn, Cd, Cu, Ni) on particles of varying size in coastal and open ocean waters. Results from the South China Sea at the South East Asia Time-Series (SEATS) station indicate that diurnal variations and spatial distribution of plankton in the euphotic zone can be easily resolved and recognized. Chemical analysis of size-fractionated particles in surface waters of the Taiwan Strait suggests that the larger particles (&#62;153 &#181;m) were mostly biologically derived, while the smaller particles (10 - 63 &#181;m) were mostly composed of inorganic matter. Apart from Cd, the concentrations of metals (Fe, Al, Mn, Cu, Ni) decreased with increasing size.

Plankton and suspended particles play a major role in the biogeochemical cycles in the ocean. Here, we provide an ultra-clean, low stress method for the collection of various sizes of particles and plankton at sea with the capability of handling large volumes of seawater.

海洋浮游生物和悬浮颗粒的超洁净多层采集装置

The distributions of many trace elements in the ocean are strongly associated with the growth, death, and re-mineralization of marine plankton and those ...

In Situ Hybridization Techniques for Paraffin-Embedded Adult Coral Samples

Corals are important ocean invertebrates that are critical for overall ocean health as well as human health. However, due to human impacts such as rising ocean temperatures and ocean acidification, corals are increasingly under threat. To tackle these challenges, advances in cell and molecular biology have proven to be crucial for diagnosing the health of corals. Modifying some of the techniques commonly used in human medicine could greatly improve researchers&#39; ability to treat and save corals. To address this, a protocol for in situ hybridization used primarily in human medicine and evolutionary developmental biology has been adapted for use in adult corals under stress.
The purpose of this method is to visualize the spatial expression of an RNA probe in adult coral tissue that has been embedded in paraffin and sectioned onto glass slides. This method focuses on removal of the paraffin and rehydration of the sample, pretreatment of the sample to ensure permeability of the sample, pre-hybridization incubation, hybridization of the RNA probe, and visualization of the RNA probe. This is a powerful method when using non-model organisms to discover where specific genes are expressed, and the protocol can be easily adapted for other non-model organisms. However, the method is limited in that it is primarily qualitative, because expression intensity can vary depending on the amount of time used during the visualization step and the concentration of the probe. Furthermore, patience is required, as this protocol can take up to 5 days (and in many cases, longer) depending on the probe being used. Finally, non-specific background staining is common, but this limitation can be overcome.

In Situ Hybridization Techniques for Paraffin-Embedded Adult Coral Samples

The goal of this protocol is to perform in situ hybridization on adult coral samples that have been embedded in paraffin and sectioned onto glass slides. This is a qualitative method used to visualize the spatial expression of an RNA anti-sense probe in paraffin-embedded tissues.

就地石蜡镶嵌成人珊瑚样品的杂交技术

Corals are important ocean invertebrates that are critical for overall ocean health as well as human health. However, due to human impacts such as rising ...

An Anaerobic Biosensor Assay for the Detection of Mercury and Cadmium

Mercury (Hg) bioavailability to microbes is a key step to toxic Hg biomagnification in food webs. Cadmium (Cd) transformations and bioavailability to bacteria control the amount that will accumulate in staple food crops. The bioavailability of these metals is dependent on their speciation in solution, but more particularly under anoxic conditions where Hg is methylated to toxic monomethylmercury (MeHg) and Cd persists in the rhizosphere. Whole-cell microbial biosensors give a quantifiable signal when a metal enters the cytosol and therefore are useful tools to assess metal bioavailability. Unfortunately, most biosensing efforts have so far been constrained to oxic environments due to the limited ability of existing reporter proteins to function in the absence of oxygen. In this study, we present our effort to develop and optimize a whole-cell biosensor assay capable of functioning anaerobically that can detect metals under anoxic condition in quasi-real time and within hours. We describe how the biosensor can help assess how chemical variables relevant to the environmental cycling of metals affect their bioavailability. The following protocol includes methods to (1) prepare Hg and Cd standards under anoxic conditions, (2) prepare the biosensor in the absence of oxygen, (3) design and execute an experiment to determine how a series of variable affects Hg or Cd bioavailability, and (4) to quantify and interpret biosensor data. We show the linear ranges of the biosensors and provide examples showing the method's ability to distinguish between metal bioavailability and toxicity by utilizing both metal-inducible and constitutive strains.

Here, we present a protocol to use an anaerobic whole-cell microbial biosensor to evaluate how different environmental variables affect the bioavailability of Hg and Cd to bacteria in anoxic environments.

一种用于检测汞和镉的厌氧生物传感器检测方法

Mercury (Hg) bioavailability to microbes is a key step to toxic Hg biomagnification in food webs. Cadmium (Cd) transformations and bioavailability to ...

Measuring the Shape and Size of Activated Sludge Particles Immobilized in Agar with an Open Source Software Pipeline

Experimental bioreactors, such as those treating wastewater, contain particles whose size and shape are important parameters. For example, the size and shape of activated sludge flocs can indicate the conditions at the microscale, and also directly affect how well the sludge settles in a clarifier.
Particle size and shape are both misleadingly &#39;simple&#39; measurements. Many subtle issues, often unaddressed in informal protocols, can arise when sampling, imaging, and analyzing particles. Sampling methods may be biased or not provide enough statistical power. The samples themselves may be poorly preserved or undergo alteration during immobilization. Images may not be of sufficient quality; overlapping particles, depth of field, magnification level, and various noise can all produce poor results. Poorly specified analysis can introduce bias, such as that produced by manual image thresholding and segmentation.
Affordability and throughput are desirable alongside reproducibility. An affordable, high throughput method can enable more frequent particle measurement, producing many images containing thousands of particles. A method that uses inexpensive reagents, a common dissecting microscope, and freely-available open source analysis software allows repeatable, accessible, reproducible, and partially-automated experimental results. Further, the product of such a method can be well-formatted, well-defined, and easily understood by data analysis software, easing both within-lab analyses and data sharing between labs.
We present a protocol that details the steps needed to produce such a product, including: sampling, sample preparation and immobilization in agar, digital image acquisition, digital image analysis, and examples of experiment-specific figure generation from the analysis results. We have also included an open-source data analysis pipeline to support this protocol.

The size and shape of particles in activated sludge are important parameters that are measured using varying methods. Inaccuracies arise from non-representative sampling, suboptimal images, and subjective analysis parameters. To minimize these errors and ease measurement, we present a protocol specifying every step, including an open source software pipeline.

利用开源软件管道测量琼脂中固定活性污泥颗粒的形状和大小

Experimental bioreactors, such as those treating wastewater, contain particles whose size and shape are important parameters. For example, the size and ...