This work was supported by the BOF grant for SG from Ghent University. AL is supported by the Rutgers University NSF Fuels-IGERT. SA is supported by the European Union Framework Programme 7 project &#8220;ProEthanol 2G.&#8221; SA and KR are supported by Ghent University Multidisciplinary Research Partnership (MRP)&#8212;Biotechnology for a sustainable economy (01 MRA 510W). JD is supported by an IOF Advanced grant (F2012/IOF-Advanced/094). KR is supported by by the ERC Starter Grant &#8220;Electrotalk&#8221;. The authors thank Tim Lacoere for designing the TOC art figure, Robin Declerck for building the strip and absorption columns and Kun Guo for providing the inoculum source.

1.装配反应堆和连接剥离和吸收单位<ol><li>收集所有必要的材料打造的电抗器:电极，框架和橡胶（见材料清单）。精心切割的所有部分相同的尺寸，以避免泄漏，而装配反应器。 </li><li>在反应堆舱钻孔，以适应公对公连接器。钻一个附加孔中的反应器隔室中的一个的一侧的中部，以适应参考电极。 </li><li>准备1 MH 2 SO 4一只股票的吸收塔。增加必要该浓度以适应氨高负荷。 </li><li>确保该膜是根据制造商的说明进行预处理。预处理碳毡电极由3分钟浸泡在2毫米CTAB（清洁剂）。冲洗毡用软化水8中的碳。稳定的阳极电化学实验不需要公关etreatment。 </li><li>根据反应器类型堆叠，以便在不同的反应器中的部分。对于生物反应器:有机玻璃终板，橡胶，不锈钢集流器，预处理石墨毡，有机玻璃反应器室中，橡胶，阳离子交换膜，橡胶垫片材料，不锈钢网电极，橡胶，有机玻璃反应器室中，橡胶，有机玻璃端板</li><li>堆反应堆部件的电化学电池如下:有机玻璃终板，橡胶，通过终板IROX阳极，有机玻璃反应堆舱，橡胶垫片，橡胶，阳离子交换膜，橡胶垫片材料，不锈钢网状电极，橡胶，有机玻璃反应器隔间，橡胶，有机玻璃终板。 </li><li>使用特氟隆密封的反应器中的连接端口。放置在同一隔室作为工作电极的参考电极:在生物电化学电池中，在电化学电池的情况下的阴极或阳极的情况下的阳极。 </li><li>用坚果和螺栓，关闭反应器。拧紧在相对侧上的螺栓，以均衡的压力。不要使用工具来关闭反应器手指拧紧就足以保证一个完全密封反应堆。 </li><li>填在反应器的水，以测试如果反应器是无泄漏。如果出现渗漏，检查螺栓是否拧紧不足或者反应器的部分之一，而移动的装配器。如果没有检测到泄漏，从反应器排空水。 </li><li>添加拉西环同时在带材和吸收柱到中途填充列。 </li><li>校准所有的泵的流速。连接的进料和再循环泵至反应器和空气泵向所述汽提和吸收单元（ 图1）。最小化管道尽可能的长度。 </li><li>用250ml的1 MH 2 SO 4的填充吸收塔，它应覆盖拉西环。确保空气流以及混合的酸当泵被接通。增加或<html>降低酸的基础上，汽提塔设计和空气泵容量的体积。 </li></ol><img alt="图1" src="/files/ftp_upload/52405/52405fig1.jpg" /> 图1.反应堆设置了生物电化学系统，使铵提取。这里介绍的系统工作在连续模式。实线表示液体流动，虚线代表气流。 <a href="https://www.jove.com/files/ftp_upload/52405/52405fig1large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图2" src="/files/ftp_upload/52405/52405fig2.jpg" /> 图2.反应器设置的生物电化学系统，使铵提取。这里介绍的系统工作在连续模式。实线表示液流，虚线表示气体的流动。ww.jove.com/files/ftp_upload/52405/52405fig2large.jpg"目标="_空白"&gt;点击此处查看该图的放大版本。 <img alt="图3" src="/files/ftp_upload/52405/52405fig3.jpg" /> 的有机玻璃反应堆帧图3.设计。每个反应器由两个端板的反应器和2的反应器室中。所有部件的厚度为2厘米。关于其他材料的大小细节，可以在材料列表中找到。 <a href="https://www.jove.com/files/ftp_upload/52405/52405fig3large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> 2.生物阳极驱动提取<ol><li>准备媒体。 <ol><li>如表1 9中描述制备的阳极液用于生物反应器，增加铵浓度在培养基中以模仿的富氮废气流。 </li><li>要存储MEDI嗯在使用前，高压灭菌的培养基，以确保碳源不通过污染耗尽。根据表1制备的维生素和痕量元素和高压灭菌和冷却介质后添加。 </li><li>通过用氮气吹扫至少30分钟以除去氧气冲洗介质。要做到这一点，插入一个管子或针入培养基并打开氮气流。 </li><li>制备导电溶液作为阴极电解液。在这种情况下，使用0.1 M氯化钠，以允许苛性生产。 </li></ol></li></ol><table border="0" cellpadding="0" cellspacing="0"><tbody><tr><td> 部件 </td><td> 量 </td><td></td><td></td></tr><tr><td>的Na 2 HPO 4 </td><td> 6克/升</td><td></td><td></td></tr><tr><td> KH 2 PO 4 </td><td> 3g / L的</td><td></td><td></td></tr><tr><td>氯化钠</td><td> 0.5克/ L的</td><td></td><td></td></tr><tr><td> 氯化铵 </td><td> 0.5克/ L的</td><td></td><td></td></tr><tr><td>硫酸镁4·7H 2 O </td><td> 0.1克/ L的</td><td></td><td></td></tr><tr><td>氯化钙2·2H 2 O解决方案（14.6克/ L） </td><td> 1毫升</td><td></td><td></td></tr><tr><td>醋酸钠</td><td>为2g / L（用于起动） </td><td></td><td></td></tr><tr><td>微量元素</td><td> 1毫升</td><td></td><td></td></tr><tr><td>维生素解决方案</td><td> 1毫升</td><td></td><td></td></tr><tr><td> 微量元素（1000倍） </td><td> 克/升 </td><td> 维生素（1000倍） </td><td> 克/升 </td></tr><tr><td> 氯化钴</td><td> 0.1 </td><td>生物素</td><td> 0.004 </td></tr><tr><td>娜2的MoO 4·2H 2 O </td><td> 0.01 </td><td>叶酸</td><td> 0。004 </td></tr><tr><td> H 3 BO 3 </td><td> 0.01 </td><td>盐酸吡哆醇</td><td> 0.02 </td></tr><tr><td> 2毫克氯2·6H 2 O </td><td> 3 </td><td>核黄素</td><td> 0.01 </td></tr><tr><td> 氯化锌 </td><td> 0.1 </td><td>盐酸硫胺素</td><td> 0.01 </td></tr><tr><td>氯化钙2·2H 2 O </td><td> 0.1 </td><td>烟酸</td><td> 0.01 </td></tr><tr><td>氯化钠</td><td> 1 </td><td> DL泛酸钙</td><td> 0.01 </td></tr><tr><td>三乙酸</td><td> 1.5 </td><td>维生素B12 </td><td> 0.0002 </td></tr><tr><td>氯化铝3·6H 2 O </td><td> 0.01 </td><td> 对氨基苯甲酸</td><td> 0.01 </td></tr><tr><td> 氯化铜</td><td> 0.01 </td><td>硫辛酸（硫辛酸）酸</td><td> 0.01 </td></tr><tr><td>三氯化铁2 </td><td> 0.1 </tD&gt; <td> 肌醇 </td><td> 0.01 </td></tr><tr><td>氯化锰2·2H 2 O </td><td> 0.5 </td><td>氯化胆碱</td><td> 0.01 </td></tr><tr><td>调整用KOH​​ pH值6.5 </td><td></td><td>烟酰胺</td><td> 0.01 </td></tr><tr><td></td><td></td><td>盐酸吡哆醛</td><td> 0.01 </td></tr><tr><td></td><td></td><td>抗坏血酸钠</td><td> 0.01 </td></tr></tbody></table> 用于生物阳极驱动铵提取表1阳极电解液组合物。 <ol start="2"><li>生物反应器的接种 注:工作在无菌条件下没有必要为这种生物反应器，作为混合培养接种体使用，反应器中的条件将选择的特定电活性生物。 <ol><li>准备接种。对于这种生物反应器，从积极的生物反应器厌氧包括发酵罐准备废水30ml的混合液，生物阳极，厌氧消化和/或原废水。收集在注射器中混合。 </li><li>连接填充有N 2的阳极液瓶的气体袋，以保持该压力，同时不允许氧气进入稳定。与阳极电解液的体积混合的接种物源（这里，将100ml的阳极液30毫升接种源的）由排空与接种注射器到培养基瓶中。一定要得到填补了阳极室所必需的量。 </li><li>使用注射器，同时填充在阳极和阴极隔室各自的解决方案。连接填充有N 2的阳极液瓶的气体袋，以使阳极液溶液可以通过取样口，而不会引入氧气被除去。关闭样品端口传输之间的水龙头。 注:与同事一起执行此步骤，以确保这两个反应堆舱同时填补。 </li><li>当两个反应堆舱都装满，开启再循环泵以大约6升/小时的再循环率。 </li><li>与三个电极连接的恒电位线，使用阳极作为工作电极。定位在所述阳极室中的参比电极。 </li><li>开关上使用恒电位软件的电位在计时模式。选择-200毫伏相对于Ag / AgCl电极的一个固定的阳极电位。 </li></ol></li><li>运行的连续反应器中进行氨提取 注意:作为生物膜的发展，目前将与乙酸盐的消耗产生的。乙耗尽的结果，电流将下降（参见结果部分， 图3）。 <ol><li>改变到连续进料，打开进料泵用于阳极和阴极。泵的转速决定了水力停留时间（HRT）。这里，操作的反应器中，在6小时的停留时间。 </li><li>开关上的带材和吸收单元的空气泵。再循环的空气在一个封闭的循环中，或循环中的开环使用的环境空气中。空气流动的配置会影响吸收效率。 </li><li>刷新每周介质三次。准备中的步骤描述新鲜的阳极和阴极2.1.1-2.1.4。 </li><li>在这些步骤之后，附加填充有N 2到闭合进料瓶的气体包，停止供给泵，把一个夹具上进水线路，开关新旧瓶和最后去除夹具和重新启动泵。 </li><li>每次进给刷新，取5毫升的阳极电解液和阴极电解液电导率，pH值，酯含量和铵浓度的测量的流出物和进水的液体样品。 </li><li>当改变进料，也取3mL的样品吸收塔监测pH值，并为TAN分析。当pH接近4，用新鲜的1M硫酸溶液代替吸收性，以确保高的吸收效率。 </li><li>由于目前会先增加，然后达到一个平台，测量王牌在阳极液流入和流出泰特内容，以确保此不会引起碳的限制:乙酸盐浓度低于100毫克/升的阳极电解液流出物表明碳的限制。增加的醋酸浓度的进料在这种情况下（ 表2）中。 </li><li>如果当前的稳定不是由醋酸引起的限制，逐渐增加氨的浓度在饲料中，并等待当前的稳定化，以便评估萃取效率（ 见表3）。 注:由于铵浓度增加，氨的毒性和高的导电性将挑战生物膜和电流最终将下降作为结果。 </li></ol></li></ol><table border="0" cellpadding="0" cellspacing="0"><tbody><tr><td> 时间 </td><td> 乙酸钠的量添加到阳极进料（克/升） </td></tr><tr><td>日0 - 35天</td><td> 2 </td></tr><tr><tD&gt; 35日 - 37日</td><td> 3 </td></tr><tr><td> 37日 - 51日</td><td> 4 </td></tr><tr><td> 51日 - 61日</td><td>五</td></tr></tbody></table> 乙酸钠中的阳极液用于生物阳极从动铵提取表2浓度的影响。 <table border="0" cellpadding="0" cellspacing="0"><tbody><tr><td> 时间 </td><td> 的NH 4 HCO 3的量添加到阳极进料（克/升） </td><td> 相 </td></tr><tr><td>日0 - 16天</td><td> 2.26 </td><td>我</td></tr><tr><td> 16日 - 26日</td><td> 4.5 </td><td> II </td></tr><tr><td> 26日 - 33日</td><td> 9 </td><td> III </td></tr><tr><td> 33日 - 40日</td><td> 14.1 </td><td> IV </td></tr><tr><td> 40日 - 47日</td><td> 20 </td><td> V </td></tr><tr&gt; <td> 47日 - 54日</td><td> 25.4 </td><td> VI </td></tr><tr><td> 54日 - 63日</td><td> 31 </td><td>七</td></tr></tbody></table> 表铵在阳极电解液为生物阳极从动铵提取3浓度的影响。各相上指示的电流密度曲线图（ 图2）。 3.电化学提取<ol><li>准备媒体<ol><li>根据表4 4制备合成废水流作为阳极液。添加硫酸铵，以达到1，3或5克N- / L的终浓度。 </li><li>制备用于阴极电解液的0.1M NaCl溶液。 </li></ol></li></ol><table border="0" cellpadding="0" cellspacing="0"><tbody><tr><td> 部件 </td><td> 量 </td></tr><tr><td>娜2 HPO 4·2H 2 O </td><td> 1.03克/ L的</td></tr><tr><td> KH 2 PO 4 </td><td> 0.58克/ L的</td></tr><tr><td>硫酸镁4·7H 2 O </td><td> 0.1克/ L的</td></tr><tr><td>氯化钙2·2H 2 O </td><td> 0.02克/ L的</td></tr><tr><td> （NH 4）2 SO 4的</td><td>根据不同的实验，得到1/3/5克N / L终浓度</td></tr></tbody></table> 电化学铵提取4表4.阳极液组成。 <ol start="2"><li>运行的连续反应器中进行氨提取<ol><li>在进给泵切换到填充在反应器隔室。为了加快该过程暂时增加泵速率。 </li><li>降低泵的转速，以获得6小时的停留时间，一旦该反应器被充满。开关上的再循环泵以6L / hr的速度。取进水（5毫升）中的样品。 注:周期性地测量的流量在整个实验以确保它不会发生变化。 </li><li>启动带和吸收单元。这个单元的操作是一样的生物反应器。 </li><li>接通使用电位软件恒电位在计时电位模式。首先应用大约为0.5 A /平方米的较低的电流密度，以极化膜和测定氮通量由于扩散独自。 </li><li>当系统已被极化为24小时，应用所必需的实验的电流密度。测试不同的电流密度，一般可达10 A /平方米至50​​ A /平方米。采取在阳极和阴极流出物，和吸收塔样品增加电流密度之前。 注:经过3次HRT，反应器应该接近稳定状态。 </li><li>一旦反应器已达到稳定状态时，至少需要3个样品上的时间过程。取从阳极和阴极流出物，以及吸收塔（每次5毫升）中的样品。写下取样量，日期和时间。 </li><li>取决于阳极进水的稳定性，取一个新的阳极流入样品如果必要的。这是必要的，当实际废水被使用。 </li><li>改变测试条件，如施加的电流密度和TAN的浓度。每次更改后，让反应器取样之前稳定至少3 HRTS。 </li><li>当吸收塔的pH接近4，用新鲜的1M硫酸溶液代替吸收性。 </li></ol></li></ol> 4.样品分析<ol><li>测量pH值和样品的电导率的同一天，采样，以减少由于挥发性氨的损失的不准确。利用适当校准的pH值和电导率的探针测量pH值和电导率。 </li><li>如果样品不立即测量，存储样本TAN分析（两个反应器）和脂肪酸分析（生物反应器），在4℃。从生物反应器阳极污水和进水通过0.45微米的过滤器过滤样本重新移动量，并帮助保护脂肪酸。填充所有样品管在轮圈，以便最小化的NH 3的损失。 </li><li>通过标准的水蒸气蒸馏法或用于测量TAN 10的任何其他可靠的方法测量氮气作为TAN。 </li><li>测量脂肪酸如乙酸通过任何可靠的方法，例如离子色谱法或气相色谱11。 </li></ol> 5.数据分析和计算<ol><li>从软件出口的恒电位仪的数据文件，并将其导入到电子表格程序。计算每小时平均值电化学变量以减小的数据点的数量，并绘制它们时平滑曲线。 </li><li>收集在一个数据文件中的所有测量数据（pH值，铵，VFA）进行计算。该计算结果部分讨论。 </li><li>由生物反应器计算当前的生产。这是最好的表示为电流密度，其计算方法如下（式1，12）: <img alt="式（1）" fo:content-width="1in" src="/files/ftp_upload/52405/52405eq1.jpg" width="100" />式（1） 其中j为电流密度，我的绝对电流，电极的投影表面积。在某些软件，它能够具有这种由实验开始前进入阳极表面积自动计算。 </li><li>计算与铵提取参数<ol><li>计算氮通量。正常化氮气通量（克N /平方米/天），以在膜表面面积，然后表示为电流密度（I N）。使用此值来计算的CE（式2，3和4）: <img alt="公式2" fo:content-width="2in" src="/files/ftp_upload/52405/52405eq2.jpg" width="200" />公式2 其中C 的，在 （克N / L）和C 的，输出 （克N / L）的所测量的铵浓度进出阳极室，分别。 Q（L / D）是所述阳极的流量及A（米2）是膜表面面积（等于投射阳极和阴极表面积）。 </li><li>目前氮通量电流密度（I N，A /平方米）: <img alt="公式3" fo:content-width="1.5in" src="/files/ftp_upload/52405/52405eq3.jpg" width="150" />公式3 其中，z NH +（ - ）为NH 4 +的电荷，F是法拉第常数（96485℃/摩尔）和M氮的分子量（14克/摩尔）。 </li><li>计算出电流效率（CE，％），为: <img alt="公式4" fo:content-width="1.5in" src="/files/ftp_upload/52405/52405eq4.jpg" width="150" />公式4 在我的应用 （A /平方米）是应用（电化学提取）或测量（生物电化学提取）的电流密度。 </li><li>计算理论的氮通量。计算最大理论氮通量（J·N，最大，克N /平方米/天）对于给定的施加电流和膜表面积（式5）为: <img alt="公式5" fo:content-width="3in" src="/files/ftp_upload/52405/52405eq5.jpg" width="300" />公式5 </li><li>计算脱氮效率（RE，％）。参阅铵是从阳极电解液作为去除效率去除的百分比。从阳极进水和出水TAN浓度（式6）计算。 <img alt="方程6" fo:content-width="2in" src="/files/ftp_upload/52405/52405eq6.jpg" width="200" />方程6 </li><li>计算出最大理论脱氮效率（RE 最大 ，％），用于一个给定的进水TAN负荷和施加的电流（等式7）: <img alt="公式7" fo:content-width="2in" src="/files/ftp_upload/52405/52405eq7.jpg" width="200" />公式7 其中J N，应用 （克的N-米-2 D - 1）是所施加的电流密度表示为氮气通量。 </li></ol></li><li>计算气/液比为（式8）: <img alt="方程8" fo:content-width="2in" src="/files/ftp_upload/52405/52405eq8.jpg" width="200" />方程8 </li><li>计算吸收塔的最大容量。从理论上的最大氮通量ĴNmax时 ，在进水的TAN浓度（摩尔/升），操作吨，膜表面区域A内的时间，和吸收Ⅴ的体积计算的最大理论N加载到吸收塔（方程9）: <img alt="公式9" fo:content-width="2.5in" src="/files/ftp_upload/52405/52405eq9.jpg" width="250" />公式9 </li><li>计算汽提效率SE（％）（方程10）: <img alt="10式" fo:content-width="3in" src="/files/ftp_upload/52405/52405eq10.jpg" width="300" />60; 10式</li><li>计算能量输入为铵提取通过阳离子交换膜（E N，表示为千瓦时/千克氮）（式11）: <img alt="11式" fo:content-width="2in" src="/files/ftp_upload/52405/52405eq11.jpg" width="200" /> 11式 与阳极和阴极之间的ΔV所测量的电位差。在生物反应器的情况下，ΔV计算为平均为采样周期，对电化学反应器取出的平均值在整个运行。 </li></ol>

<ol>
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(82), e50800 (2013).</li><li>Ping, Q., Cohen, B., Dosoretz, C., He, Z. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Long-term+investigation+of+fouling+of+cation+and+anion+exchange+membranes+in+microbial+desalination+cells.">Long-term investigation of fouling of cation and anion exchange membranes in microbial desalination cells.</a> Desalination. 325, 48-55 (2013).</li><li>Guerin, T., Mondido, M., McClenn, B., Peasley, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Application+of+resazurin+for+estimating+abundance+of+contaminant-degrading+micro-organisms.">Application of resazurin for estimating abundance of contaminant-degrading micro-organisms.</a> Letters in Applied Microbiology. 32 (5), 340-345 (2001).</li></ol>

The authors have nothing to disclose.

这份手稿提供了必要的工具，以建立一个生物电化学和回收硫酸铵电化学电池。在结果部分提出了计算系统性能的评价提供参数。生物和电化学系统在设置和功能相似。两个系统之间的主要区别是一个固定的电流，电化学电池相对于一个固定的阳极电势的生物电化学设置的选择。固定电流对非生物的设置是必要的，以驱动电极反应，并允许还允许在本体阶段的处理的调节，从而导致稳态条件。为?...

回收的废水收益的重要性有价值的产品作为宝贵的资源变得稀缺和治疗没有恢复只占成本。废水中含有既节能又可以恢复营养物，和营养恢复可以帮助以关闭生产循环1。恢复通过厌氧消化的能量是一个成熟的过程中，而营养物的回收是不常见的。回收从液体废物流如尿液和粪便的营养物质已被广泛地研究， 例如 ，通过生产鸟粪石和氨2,3的直接汽提的。但是，需要进行化学加成是这些过程4的缺点。这里，我们提出了一种用于阳离子营养素从废物流，包括钾和铵的回收。这些营养成分的阳离子形式允许恢复使用离子选择性膜在电化学系统中。在这种情况下，electrochemic人系统由一个阳极室（其中，氧化发生）的，一个阴极室（其中，减少发生）和离子选择性膜分离的隔室中。一电压跨细胞施加以产生电流从阳极到阴极。该电压可以通过外部电源来驱动水氧化和还原反应来产生。可选择地，阳极氧化， 例如 ，有机物，可以通过电细菌，需要较少的功率催化。以闭合电路并保持电荷平衡，带电物质，必须在电极之间迁移产生的每个电子。从阳极室到跨阳离子交换膜（CEM）阴极室铵传输因此可补偿电子4,5的通量。 这里提出的技术不仅能消除从废物流铵，而且还可以复苏。总氨氮（TAN）中都存在，阿蒙的平衡鎓（NH + 4）和氨（NH 3），并且是依赖于pH和温度6。 NH 4 +是丰富地，由于高TAN浓度及近中性的pH值，在阳极室与该带正电荷的物质可以因此通过在CEM当前被驱入阴极室提供。电流驱动的水在阴极处还原，导致生产氢氧离子和氢气。的TAN平衡转移至接近100％的NH 3，由于高PH值，在阴极室（&gt; 10.0）。 NH 3是可以经由空气流通很容易地传送从汽提单元到吸收塔那里被捕获并集中在酸溶液中的气体。 这种技术具有的N-富状粪便流厌氧消化过程中减少铵毒性的潜力，从而增加从这些废物流能量回收，同时恢复营养素4。铵电化学和生物电化学提取，也可作为具有高TAN含量废物流的营养恢复技术应用，如尿液，从而避免对营养物的去除费用在污水处理厂7。 这里介绍的协议可以作为许多不同的电化学和生物电化学实验的基础，因为我们使用了模块化反应器中。不同类型的电极，膜和框架的厚度可以组合为在下面的协议说明。该协议的主要目的是提供一种用于电化学铵回收和生物电化学铵回收使用的电解池比较的装置。该系统中的提取效率，电源输入和再现性方面进行了评价。

<table border="0" cellpadding="0" cellspacing="0" width="876">
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Name of Material/ Equipment</td>
			<td style="width:192px;">Company</td>
			<td style="width:301px;">Catalog Number</td>
			<td style="width:167px;">Comments/Description</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Carbon Felt 3.18 mm Thick&#160;</td>
			<td style="width:192px;">Alfa Aesar</td>
			<td style="width:301px;">ALFA43199</td>
			<td>Used as bioanode, 110 mm x 110 mm</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Ti electrode coated with Ir MMO&#160;</td>
			<td style="width:192px;">Magneto Special Anodes (The Netherlands)</td>
			<td style="width:301px;"></td>
			<td>Used as stable anode for electrochemical tests</td>
		</tr>
		<tr height="73">
			<td height="73" style="height:74px;width:216px;">Stainless steel mesh</td>
			<td style="width:192px;">Solana (Belgium)</td>
			<td style="width:301px;">RVS 554/64: material AISI 316L, mesh width: 564 micron, wire thickness: 140 micron, mesh number: 36,6</td>
			<td>Used as cathode, 110 mm x 110 mm</td>
		</tr>
		<tr height="24">
			<td height="24" style="height:24px;width:216px;">Stainless steel plate</td>
			<td style="width:192px;">Solana (Belgium)</td>
			<td style="width:301px;">inox 304 sheet, thickness: 0,5mm</td>
			<td>Used as current collector for the bioanode</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Ag/AgCl Reference Electrode</td>
			<td style="width:192px;">Bio-Logic (France)</td>
			<td style="width:301px;">A-012167 RE-1B</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Potentiostat (VSP Multipotentiostat)&#160;</td>
			<td style="width:192px;">Bio-Logic (France)</td>
			<td style="width:301px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">EC Lab</td>
			<td style="width:192px;">Bio-Logic (France)</td>
			<td style="width:301px;"></td>
			<td>software for performing electrochemistry measurements</td>
		</tr>
		<tr height="44">
			<td height="44" style="height:44px;width:216px;">Cation Exchange Membrane</td>
			<td style="width:192px;">Membranes International (USA)</td>
			<td style="width:301px;">Ultrex CMI-7000</td>
			<td>Pretreated according to the manufacturers&#39; instructions</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Turbulence Promotor mesh</td>
			<td style="width:192px;">ElectroCell Europe A/S (Tarm, Denmark)</td>
			<td style="width:301px;">EPC20432-PP-2</td>
			<td>spacer material, 110 mm x 110 mm</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Connectors</td>
			<td style="width:192px;">Serto</td>
			<td style="width:301px;">1,281,161,120</td>
			<td>Other sizes possible, dependant on tubing type and size of holes in frames</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Strip and absorption column</td>
			<td style="width:192px;"></td>
			<td style="width:301px;"></td>
			<td>In house design</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Tubing</td>
			<td style="width:192px;">Masterflex</td>
			<td style="width:301px;">HV-06404-16</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Gas bag</td>
			<td style="width:192px;">Keika Ventures</td>
			<td style="width:301px;"></td>
			<td>Kynar gas bag with Roberts valve</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:216px;">Rashig Rings</td>
			<td style="width:192px;">Glasatelier Saillart (Belgium)</td>
			<td style="width:301px;">Raschig rings 4 x 4 mm</td>
			<td>Put inside the strip and absorption column to improve the air/liquid contact. Available with many suppliers</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Rubber sheet</td>
			<td style="width:192px;"></td>
			<td style="width:301px;"></td>
			<td>Cut to fit on the perspex frames</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Perspex reactor frames</td>
			<td style="width:192px;">Vlaeminck, Beernem</td>
			<td style="width:301px;"></td>
			<td>In-house design, see tab &#34;reactor frames&#34; in this file</td>
		</tr>
	</tbody>
</table>

electrochemically and bioelectrochemically induced ammonium recovery

Streams such as urine and manure can contain high levels of ammonium, which could be recovered for reuse in agriculture or chemistry. The extraction of ammonium from an ammonium-rich stream is demonstrated using an electrochemical and a bioelectrochemical system. Both systems are controlled by a potentiostat to either fix the current (for the electrochemical cell) or fix the potential of the working electrode (for the bioelectrochemical cell). In the bioelectrochemical cell, electroactive bacteria catalyze the anodic reaction, whereas in the electrochemical cell the potentiostat applies a higher voltage to produce a current. The current and consequent restoration of the charge balance across the cell allow the transport of cations, such as ammonium, across a cation exchange membrane from the anolyte to the catholyte. The high pH of the catholyte leads to formation of ammonia, which can be stripped from the medium and captured in an acid solution, thus enabling the recovery of a valuable nutrient. The flux of ammonium across the membrane is characterized at different anolyte ammonium concentrations and currents for both the abiotic and biotic reactor systems. Both systems are compared based on current and removal efficiencies for ammonium, as well as the energy input required to drive ammonium transfer across the cation exchange membrane. Finally, a comparative analysis considering key aspects such as reliability, electrode cost, and rate is made.
This video article and protocol provide the necessary information to conduct electrochemical and bioelectrochemical ammonia recovery experiments. The reactor setup for the two cases is explained, as well as the reactor operation. We elaborate on data analysis for both reactor types and on the advantages and disadvantages of bioelectrochemical and electrochemical systems.

计时从生物反应器的效果 的计时结果，根据公式1计算出的，显示出一个典型的曲线图，用于连续反应器（ 图4）。在实验开始时，阳极和阴极在再循环模式进行操作。这允许生物膜发展和目前生产的发作。经过5天的运行中，电流密度达到最大值，然后在当前生产的降低。这是一个指示，该生物膜缺少一个碳/电子源（ 例如 ，乙酸酯），以产?...

Watch this Scientific Journal Video about Electrochemically and Bioelectrochemically Induced Ammonium Recovery at JoVE.com

Electrochemically and Bioelectrochemically Induced Ammonium Recovery

We demonstrate the extraction of ammonium from an ammonium-rich stream using an electrochemical and a bioelectrochemical system. The reactor setup, operation and data analysis are discussed.

电化学和Bioelectrochemically诱导铵恢复

Streams such as urine and manure can contain high levels of ammonium, which could be recovered for reuse in agriculture or chemistry. The extraction of ...

electrochemically-and-bioelectrochemically-induced-ammonium-recovery

Research

Education

JoVE Journal

JoVE Core

Chemistry

Chemical Equilibrium

SCIENTISTS IN ACTION

12.6K 次观看.  Ghent University. We demonstrate the extraction of ammonium from an ammonium-rich stream using an electrochemical and a bioelectrochemical system. The reactor setup, operation and data analysis are discussed. 

视频: Electrochemically and Bioelectrochemically Induced Ammonium Recovery

Dependence of Laser-induced Breakdown Spectroscopy Results on Pulse Energies and Timing Parameters Using Soil Simulants

The dependence of some LIBS detection capabilities on lower pulse energies (&lt;100 mJ) and timing parameters were examined using synthetic silicate samples. These samples were used as simulants for soil and contained minor and trace elements commonly found in soil at a wide range of concentrations. For this study, over 100 calibration curves were prepared using different pulse energies and timing parameters; detection limits and sensitivities were determined from the calibration curves. Plasma temperatures were also measured using Boltzmann plots for the various energies and the timing parameters tested. The electron density of the plasma was calculated using the full-width half maximum (FWHM) of the hydrogen line at 656.5 nm over the energies tested. Overall, the results indicate that the use of lower pulse energies and non-gated detection do not seriously compromise the analytical results. These results are very relevant to the design of field- and person-portable LIBS instruments.

LIBS detection capabilities on soil simulants were tested using a range of pulse energies and timing parameters. Calibration curves were used to determine detection limits and sensitivities for different parameters. Generally, the results showed that there was not a significant reduction in detection capabilities using lower pulse energies and non-gated detection.

对脉冲能量和时序参数使用土壤仿制品激光诱导击穿光谱结果依赖

The  dependence of some LIBS detection capabilities on lower pulse energies (&lt;100  mJ) and timing parameters were examined using synthetic silicate ...

科研

化学

Split-and-pool Synthesis and Characterization of Peptide Tertiary Amide Library

Peptidomimetics are great sources of protein ligands. The oligomeric nature of these compounds enables us to access large synthetic libraries on solid phase by using combinatorial chemistry. One of the most well studied classes of peptidomimetics is peptoids. Peptoids are easy to synthesize and have been shown to be proteolysis-resistant and cell-permeable. Over the past decade, many useful protein ligands have been identified through screening of peptoid libraries. However, most of the ligands identified from peptoid libraries do not display high affinity, with rare exceptions. This may be due, in part, to the lack of chiral centers and conformational constraints in peptoid molecules. Recently, we described a new synthetic route to access peptide tertiary amides (PTAs). PTAs are a superfamily of peptidomimetics that include but are not limited to peptides, peptoids and N-methylated peptides. With side chains on both &#945;-carbon and main chain nitrogen atoms, the conformation of these molecules are greatly constrained by sterical hindrance and allylic 1,3 strain. (Figure 1) Our study suggests that these PTA molecules are highly structured in solution and can be used to identify protein ligands. We believe that these molecules can be a future source of high-affinity protein ligands. Here we describe the synthetic method combining the power of both split-and-pool and sub-monomer strategies to synthesize a sample one-bead one-compound (OBOC) library of PTAs.

Peptide tertiary amides (PTAs) are a superfamily of peptidomimetics that include but are not limited to peptides, peptoids and N-methylated peptides. Here we describe a synthetic method which combines&#160;both split-and-pool and sub-monomer strategies to synthesize a one-bead one-compound library of PTAs.

分裂和池合成及肽叔酰胺图书馆表征

Peptidomimetics are great sources of protein ligands. The oligomeric nature of these compounds enables us to access large synthetic libraries on solid ...

Preparation of Mica and Silicon Substrates for DNA Origami Analysis and Experimentation

The designed nature and controlled, one-pot synthesis of DNA origami provides exciting opportunities in many fields, particularly nanoelectronics. Many of these applications require interaction with and adhesion of DNA nanostructures to a substrate. Due to its atomically flat and easily cleaned nature, mica has been the substrate of choice for DNA origami experiments. However, the practical applications of mica are relatively limited compared to those of semiconductor substrates. For this reason, a straightforward, stable, and repeatable process for DNA origami adhesion on derivatized silicon oxide is presented here. To promote the adhesion of DNA nanostructures to silicon oxide surface, a self-assembled monolayer of 3-aminopropyltriethoxysilane (APTES) is deposited from an aqueous solution that is compatible with many photoresists. The substrate must be cleaned of all organic and metal contaminants using Radio Corporation of America (RCA) cleaning processes and the native oxide layer must be etched to ensure a flat, functionalizable surface. Cleanrooms are equipped with facilities for silicon cleaning, however many components of DNA origami buffers and solutions are often not allowed in them due to contamination concerns. This manuscript describes the set-up and protocol for in-lab, small-scale silicon cleaning for researchers who do not have access to a cleanroom or would like to incorporate processes that could cause contamination of a cleanroom CMOS clean bench. Additionally, variables for regulating coverage are discussed and how to recognize and avoid common sample preparation problems is described.

Reproducible cleaning processes for substrates used in DNA origami research are described, including bench-top RCA cleaning and derivatization of silicon oxide. Protocols for surface preparation, DNA origami deposition, drying parameters, and simple experimental set-ups are illustrated.

对于DNA折纸分析和实验准备云母和硅衬底

The designed nature and controlled, one-pot synthesis of DNA origami provides exciting opportunities in many fields, particularly nanoelectronics. Many of ...

Preparation and Characterization of Individual and Multi-drug Loaded Physically Entrapped Polymeric Micelles

Amphiphilic block copolymers like polyethyleneglycol-block-polylactic acid (PEG-b-PLA) can self-assemble into micelles above their critical micellar concentration forming hydrophobic cores surrounded by hydrophilic shells in aqueous environments. The core of these micelles can be utilized to load hydrophobic, poorly water soluble drugs like docetaxel (DTX) and everolimus (EVR). Systematic characterization of the micelle structure and drug loading capabilities are important before in vitro and in vivo studies can be conducted. The goal of the protocol described herein is to provide the necessary characterization steps to achieve standardized micellar products. DTX and EVR have intrinsic solubilities of 1.9 and 9.6 &#181;g/ml respectively Preparation of these micelles can be achieved through solvent casting which increases the aqueous solubility of DTX and EVR to 1.86 and 1.85 mg/ml, respectively. Drug stability in micelles evaluated at room temperature over 48 hr indicates that 97% or more of the drugs are retained in solution. Micelle size was assessed using dynamic light scattering and indicated that the size of these micelles was below 50 nm and depended on the molecular weight of the polymer. Drug release from the micelles was assessed using dialysis under sink conditions at pH 7.4 at 37 oC over 48 hr. Curve fitting results indicate that drug release is driven by a first order process indicating that it is diffusion driven.

The goal of this protocol is to describe the preparation and characterization of physically entrapped, poorly water soluble drugs in micellar drug delivery systems composed of amphiphilic block copolymers.

制备及个体表征和多载药物理截留聚合物胶束

Amphiphilic block copolymers like polyethyleneglycol-block-polylactic acid (PEG-b-PLA) can self-assemble into micelles above their critical micellar ...

Unraveling Entropic Rate Acceleration Induced by Solvent Dynamics in Membrane Enzymes

Enzyme catalysis evolved in an aqueous environment. The influence of solvent dynamics on catalysis is, however, currently poorly understood and usually neglected. The study of water dynamics in enzymes and the associated thermodynamical consequences is highly complex and has involved computer simulations, nuclear magnetic resonance (NMR) experiments, and calorimetry. Water tunnels that connect the active site with the surrounding solvent are key to solvent displacement and dynamics. The protocol herein allows for the engineering of these motifs for water transport, which affects specificity, activity and thermodynamics. By providing a biophysical framework founded on theory and experiments, the method presented herein can be used by researchers without previous expertise in computer modeling or biophysical chemistry. The method will advance our understanding of enzyme catalysis on the molecular level by measuring the enthalpic and entropic changes associated with catalysis by enzyme variants with obstructed water tunnels. The protocol can be used for the study of membrane-bound enzymes and other complex systems. This will enhance our understanding of the importance of solvent reorganization in catalysis as well as provide new catalytic strategies in protein design and engineering.

Channels for the transportation of water molecules in enzymes influence active site solvation and catalysis. Herein we present a protocol for the engineering of these additional catalytic motifs based on in silico computer modeling and experiments. This will enhance our understanding of the influence of solvent dynamics on enzyme catalysis.

揭开熵率的加速溶剂动力学的膜酶诱导

Enzyme catalysis evolved in an aqueous environment. The influence of solvent dynamics on catalysis is, however, currently poorly understood and usually ...

Synthesis, Characterization, and Functionalization of Hybrid Au/CdS and Au/ZnS Core/Shell Nanoparticles

Plasmonic nanoparticles are an attractive material for light harvesting applications due to their easily modified surface, high surface area and large extinction coefficients which can be tuned across the visible spectrum. Research into the plasmonic enhancement of optical transitions has become popular, due to the possibility of altering and in some cases improving photo-absorption or emission properties of nearby chromophores such as molecular dyes or quantum dots. The electric field of the plasmon can couple with the excitation dipole of a chromophore, perturbing the electronic states involved in the transition and leading to increased absorption and emission rates. These enhancements can also be negated at close distances by energy transfer mechanism, making the spatial arrangement of the two species critical. Ultimately, enhancement of light harvesting efficiency in plasmonic solar cells could lead to thinner and, therefore, lower cost devices. The development of hybrid core/shell particles could offer a solution to this issue. The addition of a dielectric spacer between a gold nanoparticles and a chromophore is the proposed method to control the exciton plasmon coupling strength and thereby balance losses with the plasmonic gains. A detailed procedure for the coating of gold nanoparticles with CdS and ZnS semiconductor shells is presented. The nanoparticles show high uniformity with size control in both the core gold particles and shell species allowing for a more accurate investigation into the plasmonic enhancement of external chromophores.

The synthesis of uniform gold nanoparticles coated with semiconductor shells of CdS or ZnS is performed. The semiconductor coating is conducted by first depositing a silver sulfide shell and exchanging the silver cations for zinc or cadmium cations.

合成，表征和混合金/硫化镉和Au / ZnS核/壳纳米颗粒功能化

Plasmonic nanoparticles are an attractive material for light harvesting applications due to their easily modified surface, high surface area and large ...

Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates

Functions of clusters in nano or sub-nano scale significantly depend on not only kinds of their components but also arrangements, or symmetry, of their components. Therefore, the arrangements in the clusters have been precisely characterized, especially for metal complexes. Contrary to this, characterizations of molecular arrangements in supramolecular clusters composed of organic molecules are limited to a few cases. This is because construction of the supramolecular clusters, especially obtaining a series of the supramolecular clusters, is difficult due to low stability of non-covalent bonds compare to covalent bonds. From this viewpoint, utilization of organic salts is one of the most useful strategies. A series of the supramolecules could be constructed by combinations of a specific organic molecule with various counter ions. Especially, primary ammonium carboxylates are suitable as typical examples of supramolecules because various kinds of carboxylic acids and primary amines are commercially available, and it is easy to change their combinations. Previously, it was demonstrated that primary ammonium triphenylacetates using various kinds of primary amines specifically construct supramolecular clusters, which are composed of four ammoniums and four triphenylacetates assembled by charge-assisted hydrogen bonds, in crystals obtained from non-polar solvents. This study demonstrates an application of the specific construction of the supramolecular clusters as a strategy to conduct systematical symmetric study for clarification of correlations between molecular arrangements in supramolecules and kinds and numbers of their components. In the same way with binary salts composed of triphenylacetates and one kind of primary ammoniums, ternary organic salts composed of triphenylacetates and two kinds of ammoniums construct the supramolecular clusters, affording a series of the supramolecular clusters with various kinds and numbers of the components.

This article describes construction of a series of hydrogen-bonding supramolecular clusters in crystals using primary ammonium triphenylacetates, which are recrystallized from non-polar solvents. This selective construction of the supramolecular clusters leads to effective systematical symmetric studies about a correlation between the supramolecular clusters and their components.

建筑和超分子集群与二元或三元铵Triphenylacetates一系列的体制性对称研究

Functions of clusters in nano or sub-nano scale significantly depend on not only kinds of their components but also arrangements, or symmetry, of their ...

Green and Low-cost Production of Thermally Stable and Carboxylated Cellulose Nanocrystals and Nanofibrils Using Highly Recyclable Dicarboxylic Acids

Here we demonstrate potentially low cost and green productions of high thermally stable and carboxylated cellulose nanocrystals (CNCs) and nanofibrils (CNF) from bleached eucalyptus pulp (BEP) and unbleached mixed hardwood kraft pulp (UMHP) fibers using highly recyclable dicarboxylic solid acids. Typical operating conditions were acid concentrations of 50 - 70 wt% at 100 &#176;C for 60 min and 120 &#176;C (no boiling at atmospheric pressure) for 120 min, for BEP and UMHP, respectively. The resultant CNCs have a higher thermal degradation temperature than their corresponding feed fibers and carboxylic acid group content from 0.2 - 0.4 mmol/g. The low strength (high pKa of 1.0 - 3.0) of organic acids also resulted in CNCs with both longer lengths of approximately 239 - 336 nm and higher crystallinity than CNCs produced using mineral acids. Cellulose loss to sugar was minimal. Fibrous cellulosic solid residue (FCSR) from the dicarboxylic acid hydrolysis was used to produce carboxylated CNFs through subsequent mechanical fibrillation with low energy input.

Here we demonstrate a novel method for green and sustainable productions of highly thermally stable and carboxylated cellulose nanocrystals (CNC) and nanofibrils (CNF) using highly recyclable solid dicarboxylic acids.

热稳定和羧基化纤维素纳米晶和纳米原纤维使用高度可回收的二元羧酸绿色和低成本生产

Here we demonstrate potentially low cost and green productions of high thermally stable and carboxylated cellulose nanocrystals (CNCs) and nanofibrils ...

Probing the Structure and Dynamics of Interfacial Water with Scanning Tunneling Microscopy and Spectroscopy

Water/solid interfaces are ubiquitous and play a key role in many environmental, biophysical, and technological processes. Resolving the internal structure and probing the hydrogen-bond (H-bond) dynamics of the water molecules adsorbed on solid surfaces are fundamental issues of water science, which remains a great challenge owing to the light mass and small size of hydrogen. Scanning tunneling microscopy (STM) is a promising tool for attacking these problems, thanks to its capabilities of sub-&#197;ngstr&#246;m spatial resolution, single-bond vibrational sensitivity, and atomic/molecular manipulation. The designed experimental system consists of a Cl-terminated tip and a sample fabricated by dosing water molecules in situ onto the Au(111)-supported NaCl(001) surfaces. The insulating NaCl films electronically decouple the water from the metal substrates, so the intrinsic frontier orbitals of water molecules are preserved. The Cl-tip facilitates the manipulation of the single water molecules, as well as gating the orbitals of water to the proximity of Fermi level (EF) via tip-water coupling. This paper outlines the detailed methods of submolecular resolution imaging, molecular/atomic manipulation, and single-bond vibrational spectroscopy of interfacial water. These studies open up a new route for investigating the H-bonded systems at the atomic scale.

Here, we present a protocol to investigate the structure and dynamics of interfacial water at the atomic scale, in terms of submolecular resolution imaging, molecular manipulation, and single-bond vibrational spectroscopy.

用扫描隧穿显微镜和光谱法探讨界面水的结构和动力学

Water/solid interfaces are ubiquitous and play a key role in many environmental, biophysical, and technological processes. Resolving the internal ...

Constructing Thioether/Vinyl Sulfide-tethered Helical Peptides Via Photo-induced Thiol-ene/yne Hydrothiolation

Here, we describe a detailed protocol for the preparation of thioether-tethered peptides using on-resin intramolecular/intermolecular thiol-ene hydrothiolation. In addition, this protocol describes the preparation of vinyl-sulfide-tethered peptides using in-solution intramolecular thiol-yne hydrothiolation between amino acids that possess alkene/alkyne side chains and cysteine residues at i, i+4 positions. Linear peptides were synthesized using a standard Fmoc-based solid-phase peptide synthesis (SPPS). Thiol-ene hydrothiolation is carried out using either an intramolecular thio-ene reaction or an intermolecular thio-ene reaction, depending on the peptide length. In this research, an intramolecular thio-ene reaction is carried out in the case of shorter peptides using on-resin deprotection of the trityl groups of cysteine residues following the complete synthesis of the linear peptide. The resin is then set to UV irradiation using photoinitiator 4-methoxyacetophenone (MAP) and 2-hydroxy-1-[4-(2-hydroxyethoxy)-phenyl]-2-methyl-1-propanone (MMP). The intermolecular thiol-ene reaction is carried out by dissolving Fmoc-Cys-OH in an N,N-dimethylformamide (DMF) solvent. This is then reacted with the peptide using the alkene-bearing residue on resin. After that, the macrolactamization is carried out using benzotriazole-1-yl-oxytripyrrolidinophosphonium hexafluorophosphate (PyBop), 1-hydroxybenzotriazole (HoBt), and 4-Methylmorpholine (NMM) as activation reagents on the resin. Following the macrolactamization, the peptide synthesis is continued using standard SPPS. In the case of the thio-yne hydrothiolation, the linear peptide is cleaved from the resin, dried, and subsequently dissolved in degassed DMF. This is then irradiated using UV light with photoinitiator 2,2-dimethoxy-2-phenylacetophenone (DMPA). Following the reaction, DMF is evaporated and the crude residue is precipitated and purified using high-performance liquid chromatography (HPLC). These methods could function to simplify the generation of thioether-tethered cyclic peptides due to the use of the thio-ene/yne click chemistry that possesses superior functional group tolerance and good yield. The introduction of thioether bonds into peptides takes advantage of the nucleophilic nature of cysteine residues and is redox-inert relative to disulfide bonds.

We present a protocol for the construction of thioether/vinyl sulfide-tethered helical peptides using photo-induced thiol-ene/thiol-yne hydrothiolation.