这项工作是由自然科学和加拿大的设备，发现和Discovery Accelerator资助工程研究理事会授予JMBNRB支持确认来自卡内基研究所的华盛顿博士后奖学金计划的支持。斯蒂芬Elardo还之前与活塞缸机在地球物理实验室拍摄感谢他的帮助。

1）制备原料的<ol><li>合成玄武岩 注意：玄武组合物用作原料更解聚的组合物的硅酸盐，虽然越来越多的相关一个岩浆海洋的情况下，是很难或不可能以猝灭到玻璃在活塞缸和多砧实验。 <ol><li>称量组分氧化物或碳酸盐（Ca和Na）的粉末的所需量，除铁，并加入到玛瑙研钵（参见实施例中的表1）。一个铁的混合物无重〜4克应广泛的实验套件提供足够的原料。 </li><li>加乙醇至玛瑙研钵，直到粉末被淹没然后研磨为用玛瑙乳棒均匀化两者的组合物和谷物的混合物的尺寸至少为2小时。 注意：同质地面起始组合物可以通过用扫描型电子麦克风检查粉末混合物的压制丸粒进行检查roscope配备用于通过能量色散X射线光谱组成分析。 </li><li>一旦彻底均质化，将砂浆下250W的热灯，在约20厘米的距离。后的粉末混合物是干的，这可能需要20-60分钟，将其转移到任何一个氧化铝或莫来石（一种铝硅酸盐）坩埚中。 </li><li>到decarbonate该混合物，放置与粉状混合物的坩埚成箱式炉在RT和递减至1273ķ超过3-5小时的过程中。在炉中在1273 KO / N离开混合物。 </li><li>从盒子中取出炉内的脱羧混合物并使其冷却至室温。一旦冷却，称重并作为FeO的两种或Fe 2 O 3粉末（ 见表1）添加铁的混合物。变化的FeO的比例的Fe 2 O 3的同时保持总Fe含量相同允许样品的决赛 F O 2的改变。访问更多还原条件下，并在所有实验中，调查P吨，还添加〜0.5-2.0重量％的Si的混合物。一旦铁（±Si）的已被添加，通过下乙醇再次磨削用玛瑙研钵和研杵重新匀化该混合物。 </li><li>干热灯下的均质混合物，然后将其转移到一个壳管形瓶中。贮存于干燥器直到准备装载样品胶囊。 </li></ol></li><li>金属相：重，锇，铱，钌实验<ol><li>为实验目的是调查重，锇，铱或钌，制备3:1重量比（6：1为钌，考虑到在原子质量的差别）Au和感兴趣的HSE的混合物，用高纯度的金属粉末。称重〜500毫克的混合物应广泛的实验套件提供足够的原料。 </li><li>转移混合物放入石墨坩埚并盖上石墨盖。然后将覆盖的坩埚成箱式炉中以1473 K中〜5分钟的温度。一旦从炉中取出，离开坩埚盖就位，直到组件具有COO导致至RT。 注意：锇在空气中加热可能导致形成的有毒化合物，四氧化锇。锇金属也是已知的皮肤有刺激性，见MSDS为CAS＃7440-04-2。 注意：此过程熔化的金（熔点〜1337 K），但不伴随HSE，导致形成一个金属凸边，其中所关注的HSE由Au的外皮包围。 </li><li>除去从石墨坩埚内的金属凸边，并用剃刀刀片将其分成小块，其中测量〜1mm的其最长尺寸。一旦切断，将珠串成一个外壳小瓶，存放在干燥器中。 </li></ol></li><li>金属相：铂实验 注意：实验来调查的Pt，不能使用的Au涂覆珠技术由于Pt和Au中的高温下的完全混溶进行（&gt; 2042钾养分0.1兆帕32）。这排除了样品的几何形状，由此铂在物理上与硅酸盐熔体在实验中通过果皮分离非盟。 <ol><li> 1重量比，使总的〜500毫克混合物：调匀铂和铱的金属粉末的1。接下来，添加〜20毫克的金属Fe粉，使铁包括〜4％（重量）总混合物的。 </li><li>带的清洁钻头坯料（或者，也可以代替一个钻头坯件的被使用的钻头的柄）到工作台的边缘，以便〜3个毫米的桌面突出。定位的石英玻璃管，具有〜2-3毫米的内直径和〜4-6毫米的外径，到钻坯件的突出端。 </li><li>将PtIrFe混合成玻璃管插入另一个上面钻空。两个钻坯的直径应比石英玻璃管的内径不大于0.1毫米。冷压通过用手推动钻坯一起的金属混合物（ 图2）。 注意：在寒冷的压制步骤用力过大可能会导致石英玻璃破碎）。 </li><li>把冷压粉末，仍然石英玻璃管内，放进氧化铝坩埚中并悬浮在气体混合垂​​直管炉的凉爽部。增加炉温至1673 K和使用CO-CO 2气体的混合物，设置炉˚FO 2的值接近该铁方铁矿缓冲器。 注意：在环境压力和1673 K时，铁-方铁矿缓冲器对应于1.93×10 -10 A F O 2帕33。混合比，温度和 f O 2 CO CO 2之间的关系可以在参考34中找到。为在1673 K时铁方铁矿缓冲器使用的气体混合物，其包含22.25％（体积）的CO 2和77.75％（体积）CO。 <ol><li>一旦所期望的温度和 f O 2的均达到，降低氧化铝坩埚，以便它驻留在炉热点和离开O / N为粉饼退火。 </li></ol></li><li>卸下crucIBLE并压制粉末从气 - 混合炉并让它们先冷却。如果二氧化硅玻璃管仍然完好，使用一个钻头坯料推退火粉末出管道。采用钢丝钳，打破退火粉末成片足够小以适合选择用于实验样品胶囊内。 </li><li>直到需要的传送在干燥器的金属件外壳小瓶和存储。 </li></ol></li><li>金属相：多砧实验<ol><li>进行实验，以确定的适度并稍微亲铁元素的分区，混合的合成的玄武岩粉末与铁金属粉末比例相等。 注：铁的某些部分可以被添加作为Fe-Si合金，通常使硅包含&lt;8％（重量）的金属部分。这将确保实验˚FO 2仍然很低。 </li><li>添加所选择的微量元素作为金属氧化物粉末的玄武岩加金属混合物。通过均质克原料下乙醇inding用玛瑙研钵和研杵。正在研究加入将取决于元件上微量元素的确切量，然而，名义浓度的几千ppm至2％（重量）是典型的10,35。 </li><li>一旦均质化，干粉状原料在热灯下，直到需要在干燥器将其传送到一个​​壳管形瓶中，然后存储。 </li></ol></li></ol> 2.准备装配组件<ol><li>活塞缸 注意：活塞缸组件包括被支撑在利用可压碎氧化镁件的石墨电阻加热器的热点石墨胶囊。氧化铝铠装热电偶位于轴向穿过该组件的上部在样品的顶部，以监测温度。炉然后通过的BaCO 3细胞同时作为压力介质和热绝缘体36包围。装配尺寸在提供图3A。在表2中提供用于实验及其来源例如材料的列表。 <ol><li>机的石墨胶囊，石墨的端塞和氧化镁支撑件所需的尺寸与中心车床，用高纯度石墨和氧化镁棒或管分别作为原料（ 图3A）。 注意：对于实验，调查重，Os和Ir，HSE -铁合金可代替石墨作为胶囊材料29,30。 </li><li>超声处理在乙醇石墨胶囊〜1分钟，在室温，然后干燥下以相同的方式加热灯的指示为粉状的原料。一旦干燥，在干燥器或烘干炉，直到所需要的胶囊传送至壳小瓶中并存储。 </li><li>将氧化镁支撑件在任一氧化铝或莫来石坩锅和退火在1573 K的一箱式炉中在至少8小时。退火之后，使片冷却，然后存储在干燥炉中保持在〜393 K. </li><li>为了使碳酸钡细胞，第一混合的BaCO 3粉末和使用的复印墨粉在99：1的比例（重量）。最少需要的7.4克混合物的一个实验。涂层了适当大小的钢模具以任一石墨系干润滑剂或PTFE基脱模剂（ 表2）的内部部分（ 见图3A为的的BaCO 3套筒尺寸）。 </li><li>冷压3.7克使用钢模具和液压机〜250兆帕的混合物。离开在压力将混合物减压之前1分钟。这将产生一个套筒为17毫米的高度。两个袖子都需要每个组件。 注意：上面描述的和在一些以前的研究29中所用的2-细胞排列- 31可被取代为一个单一的BaCO 3细胞提供一个适当大小的模具可用。 </li><li>一旦从除去死，驱动断复制调色剂通过从室温加热套筒923ķ在几个小时的过程中在箱式炉，然后保持在该温度约30分钟。注意到橙色的颜色变化从黑色一次复制调色剂已被删除。存储袖子退火烤箱维持在393〜K的干燥</li></ol></li><li>多砧 注意：多砧组件包括被使用的可压碎的MgO或Al 2 O 3填料件定位在一圆柱形石墨电阻加热器的热点的示例胶囊。加热器由或烧结或浇注陶瓷八面体，作为两个压力介质和热绝缘体包围。热电偶可位于任一轴向或横向，这取决于该组件的设计。有无数的大小和组件的设计用于多砧实验中，根据所需的目的和 P - T条件图4显示一个如sembly设计以前使用的3.6和7.7的GPA 35进行金属硅酸盐分区实验。 <ol><li>所示为活塞筒实验制备由高纯度管石墨胶囊和可压碎氧化镁或氧化锆套筒以相同的方式。所需的尺寸是在图4A中提供。 </li><li>使从硬烧结氧化铝棒的长度的氧化铝塞。使用菱形文件的得分棒的地方是被破碎，然后将其卡在杆用手所需的长度（ 见图4A为尺寸）。使用文件删除所造成的破坏杆的任何毛刺。通过在RT超声波处理乙醇清洁插头。 </li><li>制备八面体，使用MgO的浇注料2部分陶瓷18毫米八面体边缘长度（OEL）（ 见表2）和适当大小的模具中。该模具包括一个夹具持有8截短的​​立方体，其厚度等于期望第分离片Ë预成型垫片37。 <ol><li>对于八面体与18毫米OEL，采用立方体与11毫米截断边长（TEL）和片材的3毫米厚。使用铝或PVC多维数据集和片材。组装模具，润滑油会接触可浇注陶瓷硅脂所有部分。留一个立方体未组装，以提供入口点用于陶瓷混合物。 </li><li>结合的粉末陶瓷和液体活化剂在一个100：30的重量比充分混合。将混合物倒入模具中，以确保有空气没有聚积口袋。插入其余立方体，并允许该混合物至少2小时进行设置。每个八面体需要〜15克陶瓷的混合物。 </li></ol></li><li>一旦设定，从模具中取出的八面体，在干燥炉中在393 10k，则退火在箱式炉为〜2小时脱水为约1天，在1,273-1,373ķ。 </li><li>允许八面体冷却至室温空气中，然后钻7.3毫米直径的孔中的说明图4B以容纳绝缘套管，石墨加热器及剩余样本组件。 </li><li>储存在干燥炉中在〜393ķ直到准备组装的实验。 </li></ol></li></ol> 3.装配组件的<ol><li>活塞缸实验大会<ol><li>通过首先插入HSE轴承金属再加入合成玄武岩粉末直到胶囊填充加载石墨样品胶囊。使用的重力稳定装置在实验过程中最小化的机会翻转并且旨在防止金属相的分散体通过机械作用。 </li><li>将少量的干的MgO粉末（典型地&lt;50毫克）在设计成保持样本胶囊的空腔的底部。这个变平钻洞时创建的锥面，进而降低了样本期间压缩剪切力，可能会破裂胶囊。 </li><li>组装所有以前疯狂如图3B E组分。 </li><li>包裹的一块30微米厚的铅箔的组件周围，在所述较低的BaCO 3套筒的外露端折叠箔的小（〜1.5毫米）部分。插入装配 ​​成12.7毫米孔碳化钨压力容器，以及一个底座插栓（上）和钢端片（下）， 如图3A所示 。 注：最终加载活塞缸设备具有两个液压油缸。桥跨在下部柱塞允许碳化钨活塞将压力施加到样品的底部。上压头固定在上侧试料表面的位置，并施加最终负载到压力容器，使额外的支持以碳化钨芯38。 图3C示出在多伦多大学的活塞气缸装置与地方的桥梁。摩擦校正-9％被施加到帐户标称样品压力之间的差的ð所经历的样品39。 </li><li>定位的液压缸之间的桥梁，压力容器及底板。下一步使用4孔硬烧结氧化铝管具有1.6毫米的外径为C型热电偶。在氧化铝管应切断足够长，以允许〜1-2毫米的管子从顶部板的上表面突出。 </li><li>订阅两个导线的组合物（ 见表2）通过在管相邻的孔，通过180度转动的端部和将其固定在相对 ​​的孔，以使导线交叉。插入热电偶穿过顶板和进入组件，以使结是样品的正上方。绝缘采用柔性聚四氟乙烯管热电偶导线的剩余部分，​​留露底10-20毫米的部分。 </li><li>将任何所需的金属衬垫中的顶板和上压头之间的地方。在组装过程中，位置的Mylar片材的上方的压力容器之间的大会和上压头的顶部。这些片电隔离从装置的其余部分样品加热电路。 </li></ol></li><li>多砧实验大会<ol><li>使使用4孔硬烧结氧化铝管通过在管相邻的孔馈送，导线，通过180°旋转的端部，并把它们固定在相对的孔的C型热电偶。绝缘导线的其余部分与氧化铝管的长度短（约20毫米），然后特氟隆绝缘材料，在端留下裸露导线的10-20毫米的部分。 </li><li>插入锆套筒和石墨加热器成八面体，再切槽， 如图4B所示。将热电偶插入八面体的顶部和氧化铝覆盖臂定位到凹槽。使用氧化锆水泥（ 见表2），以填补围绕热电偶空隙空间并晾干。 </li><li>为了分离热电偶乔在从石墨胶囊，从八面体的基部添加氧化镁粉末，直到露出导线都包括在内。小于50毫克的粉末通常足以包围所述露出的线。为确保氧化镁粉紧密堆积，使用钻坯平息的散粉。 </li><li>加载石墨胶囊与先前制备的样品材料，并放置到从开口侧的八面体。插入氧化铝塞完成八面体的组装。 </li><li>上4了WC立方体（ 表2）使用聚乙酸乙烯酯粘合轻木，一个在每个相邻的立方体的截头拐角的3个面的短的长度。每个轻木片应该测量〜4.4毫米在高度和宽度由〜9.0毫米长度，对于图4中所示的八面体大小。在每个面，在所述截短的边缘相对的象限定位轻木碎片。 </li><li>组装4立方体的形成方形平面视图，2和2没有wooden个连接。东方截断边缘面对广场的中心。 </li><li>定位八面体在立方体的中心，因此，它是支持的截断边缘。接角热电偶武器，使他们从广场对面的角落出现（ 图5A） </li><li>将剩余的立方体WC进入位置，形成与八面体为中心的立方体，以确保与木制件的附加立方体之上剩下那些没有木垫片立方体。 </li><li>胶方片厚度为0.5mm的G10片（见表2），以用氰丙烯酸酯类粘合剂的组装立方体的每个面528。对于32 mm水柱的立方体，用G10表测量〜55毫米×55毫米。两了WC立方体具有截短了接触电阻加热器，从而形成电加热回路的一部分。为此接触这些立方体片材，切割2窄（&lt;1毫米宽）， 如图5B所示，并把一块铜箔使得狭缝我T公司提供一个点的第一和第二阶段的铁砧之间的接触。 注意：多砧装置利用包含在保持环内砧块的一个2级系统。第一阶段砧包括形成一个中心立方空腔6可拆卸楔子。这个腔容纳8碳化钨的立方体，被截断的角落（第二阶段砧）围绕陶瓷八面体40。因此，通过液压机施加到第一级砧垂直定向力被传递到所述八面体的方式，其导致样品的准静水压缩。在压头和试样的压力油压力之间的关系可以被校准为这里描述使用由41所概述的程序18毫米的OEL铸造八面体组件。 </li><li>切2片0.076毫米厚的聚酯薄膜用干燥的PTFE润滑剂在图6和外衣它们显示的尺寸。 <ol><li>预切割片材进的位置的一个锁紧环（在基地直边），然后插入下置的1次-工 ​​段砧，其本身被备份与0.076毫米厚的聚酯薄膜和涂有聚四氟乙烯的润滑油（ 图5B）。下部集砧块可留在运行之间的地方。将组装好的立方体进入下集第一阶段铁砧和连接热电偶武器平衡热电偶导线的退出压力模块。 </li><li>定位第二预切割聚酯薄膜片到保持环（直边顶端）和插入的1次-工 ​​段砧，这应该是聚酯薄膜的支持和润滑中相同的方式下组上部集。该布置产生了润滑麦拉到第1次-工 ​​段的砧座和保持环相比单聚酯薄膜片布置37，其减少柱塞推力的损失摩擦由〜30％之间的聚酯薄膜接触。 注意：厚度和聚酯薄膜片的尺寸将取决于吨所使用的压力模块的准确，他设计的。上文和图6中所述的尺寸在使用中的地球物理实验室，华盛顿卡内基研究所。 </li></ol></li></ol></li></ol> 4.运行实验<ol><li>一旦样品被带到所需的压力，热，在100 K / min的速率，直到所需的驻留温度为止。在加热过程中，油在样品柱塞可能需要以保持恒定的油压进行调整。 </li><li>的停留时间后，通过切断电源，炉猝灭样品。一旦该装置已冷却至室温，慢慢地解压缩的样本。 </li></ol> 5.运行产品分析<ol><li>对于活塞缸实验，提取实验成品使用液压油缸的压力容器。有一对重型刀具去除组件，以释放石墨胶囊（外侧部分活塞CYLINDER），或炉含有样品囊和支撑件（多砧）。 </li><li>安装在环氧树脂样品（典型地，以形成25.4毫米直径的冰球）（ 图7A）。使用320到600号粒度的碳化硅纸，研磨到样品，以暴露猝灭硅酸盐熔体和金属相。使用抛光或者氧化铝或金刚石悬浮液以减少磨粒尺寸范围从15〜0.3微米的暴露的表面。 </li><li>通过电子探针微量分析仪（EPMA）碳涂层的抛光样品42的表面和分析金属和硅酸盐运行产品的主要元件组合物。使用散焦（10微米）的光束直径为硅酸盐分析，以避免碱元素迁移远离电子束。用于与上述协议生成先前取样表征分析条件和标准可以在参考文献中找到29 - 31,35 注意：对于实验investigatËMSE和SSE分区，EPMA也可能被证明适合示踪元素的分析，提供它们存在足够的浓度。 </li><li>以下几大因素分析，除去碳涂层采用0.3微米的氧化铝颗粒。使用激光烧蚀电感耦合等离子体质谱（LA-ICPMS），以确定在运行产品的微量元素的含量。的介绍，通过采样LA-ICPMS分析，请参见参考文献43。 注意：对于钙和镍的以前的HSE溶解度研究同位素已成功地被用作内部标准，以减少数据，同时使用玻璃和硫化物的参考材料分别29,30。所有分析前应先单程消融，随后冲洗消融细胞为至少60秒。这保证了可能源于抛光实验运行的产品不影响结果的任何表面污染。 </li></ol>

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利用这里所概述的协议执行包含无实验的结果先前已经比较了在引用29（锇，铱，金），30（重，金）和31（Pt）的文献数据。铂是最有启发性的展示出包容，自由运行，产品的实用性。在低˚FO 2的运行实验，厄特尔等人 48分配夹杂到稳定原点，因此限制数据还原到的时间分辨的LA-ICPMS谱最低计数每秒的区域。这种方法可以减少夹杂物测得的硅?...

地面积被认为已经发生一系列星子之间的碰撞与球粒陨石主体组成，终止于一个巨大的冲击相认为负责对月球的形成1,2。在原土通过影响和短命的同位素衰变热足以引起广泛熔融和岩浆海洋或通过密集的富铁金属熔体可能下降池塘的形成。一旦到达岩浆海洋的基础上，金属熔体遇到流变边界，失速，并进行最后的金属-硅酸盐平衡之前通过固体地幔最终降到生长芯2。金属和硅酸盐阶段为金属熔体之间的进一步化学通讯穿过地幔的固体部分被认为是排除由于大尺寸的金属底辟3快速下降。地球的该初级分化成金属芯和硅酸盐MANT6 -乐是由两个地球物理和地球化学观测4今天透露。解释这些观测以一个岩浆海基，得到合理的条件为金属硅酸盐平衡，但是，需要的实验结果的一个适当的数据库。 原始上地幔（PUM）是一个假设的水库，包括核心的形成硅酸盐残留物，因此，其组成反映微量元素中的金属硅酸盐平衡的行为。微量元素在其地球化学亲和力的基础上芯偏析分布式金属和硅酸盐熔体之间。一个元件偏爱的金属相的大小可通过金属 - 硅酸盐的分配系数进行说明<img alt="式（1）" src="/files/ftp_upload/52725/52725eq1.jpg" /><img alt="公式（2）" src="/files/ftp_upload/52725/52725eq2.jpg" /> （1） 哪里<img alt="公式3" src="/files/ftp_upload/52725/52725eq3.jpg" />和<img alt="公式4" src="/files/ftp_upload/52725/52725eq4.jpg" />表示元素的浓度i的金属和硅酸盐熔体分别。值<img alt="公式5" src="/files/ftp_upload/52725/52725eq5.jpg" /> &gt; 1表明亲铁元素（铁爱好）的行为和那些&lt;1亲石（岩爱好）的行为。该亲铁元素的PUM组成秀估计相对枯竭，以7球粒陨石，通常被认为是代表地球的整体组合物6,8。这枯竭的原因是亲铁元素的由核心封存，并为难治性元素的幅度应该直接反映的价值观<img alt="公式5" src="/files/ftp_upload/52725/52725eq5.jpg" /> 。因此，实验室的实验试图确定的值<img alt="公式5" src="/files/ftp_upload/52725/52725eq5.jpg" />过岭NGE的压力（P），温度（T）和氧逸度（六O 2）是相关的，从一个岩浆海洋底层金属偏析的条件。这些实验的结果随后可用于描绘的p区- 笔- ˚FO 2的空间是与多个亲铁元素的PUM丰兼容（ 例如 ，9 - 11）。 高压力和相关的一个岩浆海洋场景温度可以重新创建在使用一个活塞 - 气缸或多砧按实验室。活塞 - 缸体装置提供访问到中等压力（〜为2GPa）和高温（〜2573 K）的条件下，但使大体积样品和各种胶囊材料可以很容易地使用。快速冷却速率也允许的范围内的硅酸盐熔体组合物的骤冷至其玻璃，从而简化了运行的产品的质地解释。多砧装置通常采用小体积的样品，但用合适的组件设计可以实现压力高达〜27帕和温度〜3000 K的使用这些方法允许对数据分区为多个的适度并稍微亲铁元素为聚集在大范围的对 - T 的条件。根据这些数据的PUM组合物的预测表明金属 - 硅酸盐平衡分别发生在平均压力和温度条件下在过量的〜29帕和3000 K，但确切的值是模型依赖性。为了解释某些氧化还原敏感元件的PUM丰度（ 例如，钒，铬）的F 的 O 2也被认为从下通过共现有铁和方铁矿强加〜4到2个对数单位积期间演进（FeO的）在相当于PT条件（铁方铁矿缓冲区）12。 虽然m的PUM丰任何亲铁元素可以在一个深岩浆海洋基座上占由金属硅酸盐平衡，它已被证明很难评估，如果这种情况也适用于最高度亲铁元素（HSE元件）。的HSE元件的铁金属通过低压力（P〜0.1兆帕）和温度（T &lt;1673 K）的实验表明极端亲和力表明所述硅酸盐地球应强烈缺乏这些元素。的HSE含量为PUM的估计，然而，仅指示一个中等耗尽相对于球粒（ 图1）。一个常用假定解决了明显的超额HSE是，地球经历了后期增生核心，形成13球粒陨石后续材料。这晚吸积物质会夹杂着PUM和提升HSE浓度，但对更丰富的元素的影响可以忽略。可替代地，已经提出，HSE元件的极亲铁性质箭头低磷 </em&gt; - T 的实验并没有坚持到在核心14,15形成目前高PT条件。为了验证这些假设，实验必须进行，以确定在适当的条件下HSE元件的溶解度和金属硅酸盐的分区。淬火运行产品的然而，许多以往的研究硅酸盐部分的污染，具有复杂的运行产品分析和遮蔽了真正的分配系数的金属和硅酸盐熔体之间的HSE元件。 在分区实验中的HSE元件存在于适当的自然浓度水平，这些元素对于铁金属的极端偏好阻止他们的测量硅酸盐熔体。为了解决这个问题，溶解度的测量是在该硅酸盐熔体饱和的兴趣和价值的HSE <img alt="公式5" src="/files/ftp_upload/52725/52725eq5.jpg" />使用鲍里索夫等的计算形式主义[16]。淬火硅酸盐运行的产品在还原条件下进行的HSE溶解度实验，然而，往往是由分散的HSE±铁的证据显示污染内含物17。尽管存在这些夹杂物在低˚F澳近无处不2实验含铂，铱，锇，铼和钌，（ 例如 ，18 - 27），有在其质地介绍研究之间显着变化;比较例如引用22和26。虽然已经证明，包含物可以形成，它们在实验28的运行条件稳定期，这并不排除夹杂物的生成，因为样品是骤冷。不确定周边夹杂物的起源使分析结果的处理困难，并导致歧义以上HSE元件的真实的溶解度降低硅酸盐融化。纳入无运行产品须评估该研究采用了能够产生准确的溶解浓度HSE的分析方法。在抑制在还原条件下金属夹杂物的形成相当大的进展已经被证明在使用活塞-气缸装置，其中，所述样本设计是从以 ​​前的研究条中，在任一的Au或Si的起始原料29实验- 31。加入Au或单体Si的起始原料分别改变实验样品的几何形状或 f O 2的演化。这些方法的目的是通过改变HSE的扩散与还原样品的定时来抑制金属夹杂物形成，并在Bennett 等 31进行了讨论。不像以前的一些尝试清理夹杂物，如机械辅助平衡和离心活塞缸的硅酸盐熔体，本协议可以无需专门appar实施的ATU并适合于高PT实验。 详细描述这里是一个活塞-缸基础的方法来确定在高温（&gt; 1873 K）为2GPa和一个 f O 2的类似的重新，锇，铱，钌，Pt和Au中的硅酸盐熔体中的溶解度铁方铁矿缓冲器。一个类似的实验设计中的应用也可能证明是成功的HSE实验在其它压力，提供所需要的相位关系，润湿性和动力学关系坚持到选定条件。然而，现有的数据，还不足以预测我们的样本设计是否会成功，在对应于深部岩浆海洋的压力。还概述是用来确定中度和轻微亲铁元素元（MSE和SSE分别）使用多砧装置划分的一般方法。扩展纳入无数据集HSE元件到高压很可能采用类似的多砧方法。火车醚，这些程序提供来约束核心偏析的条件都与地面积的阶段的装置。

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>G10 Epoxy/Fiberglass Sheet</td>
			<td>Accurate plastics, Inc.</td>
			<td>GEES.020N.3648</td>
			<td></td>
		</tr>
		<tr>
			<td>Powdered starting materials- -Oxides, metals, carbonates</td>
			<td>Alfa Aesar</td>
			<td>Specific to desired experiment</td>
			<td></td>
		</tr>
		<tr>
			<td>Castable 2-part MgO ceramic</td>
			<td>Aremco</td>
			<td>Ceramcast - 584</td>
			<td></td>
		</tr>
		<tr>
			<td>PTFE Dry Lubricant</td>
			<td>Camie-Campbell</td>
			<td>2000 TFE-Coat</td>
			<td></td>
		</tr>
		<tr>
			<td>Graphite resistance heaters</td>
			<td>Carbone of America (Now owned by Mersen USA)</td>
			<td>Custom Order</td>
			<td></td>
		</tr>
		<tr>
			<td>Barium Carbonate</td>
			<td>Chemical Products Corporation</td>
			<td>Custom Order</td>
			<td>Calcined free-flowing (CFF) grade</td>
		</tr>
		<tr>
			<td>C-Type Thermocouple Wire (W26%Re, W5%Re)</td>
			<td>Concept Alloys</td>
			<td>N/A</td>
			<td>~0.25 mm diameter is suitable for most experiments</td>
		</tr>
		<tr>
			<td>Zirconia Cement</td>
			<td>Cotronics; Resbond 940 2-part cement</td>
			<td>N/A</td>
			<td>Use 100 parts powder for every 25 to 28 parts activator</td>
		</tr>
		<tr>
			<td>Polyvinyl Acetate (PVA) Glue</td>
			<td>e.g Bostik</td>
			<td>N/A</td>
			<td>Often sold as &#39;white glue&#39;</td>
		</tr>
		<tr>
			<td>Cyanoacrylate Glue</td>
			<td>e.g Krazy Glue/Loctite</td>
			<td>N/A</td>
			<td></td>
		</tr>
		<tr>
			<td>Piston cylinder pressure vessel and WC piston</td>
			<td>Hi-Quality Carbide Tooling Inc.</td>
			<td>Custom Order</td>
			<td></td>
		</tr>
		<tr>
			<td>Silica Glass Tubing</td>
			<td>Quartz Plus</td>
			<td>Custom Order</td>
			<td></td>
		</tr>
		<tr>
			<td>Crushable ZrO2 tubes</td>
			<td>Saint-Gobain</td>
			<td>Custom Order</td>
			<td></td>
		</tr>
		<tr>
			<td>Crushable MgO rods and tubes</td>
			<td>Saint-Gobain</td>
			<td>Custom Order</td>
			<td></td>
		</tr>
		<tr>
			<td>WC cubes for multi-anvil experiments</td>
			<td>Tungaloy</td>
			<td>Custom Order</td>
			<td>Cubes are grade-F WC alloy</td>
		</tr>
		<tr>
			<td>Single hole alumina tube for multi-anvil thermocouple</td>
			<td>Vesuvius McDanel</td>
			<td>AXS071730-04-06</td>
			<td></td>
		</tr>
		<tr>
			<td>4-hole alumina tube for piston cylinder thermocouple</td>
			<td>Vesuvius McDanel</td>
			<td>AXF1159--07-12&#160;</td>
			<td></td>
		</tr>
		<tr>
			<td>4-hole alumina tube for multi-anvil thermocouple</td>
			<td>Vesuvius McDanel</td>
			<td>AXF1159-04-06</td>
			<td></td>
		</tr>
	</tbody>
</table>

metal-silicate partitioning at high pressure and temperature: experimental methods and a protocol to suppress highly siderophile element inclusions

Estimates of the primitive upper mantle (PUM) composition reveal a depletion in many of the siderophile (iron-loving) elements, thought to result from their extraction to the core during terrestrial accretion. Experiments to investigate the partitioning of these elements between metal and silicate melts suggest that the PUM composition is best matched if metal-silicate equilibrium occurred at high pressures and temperatures, in a deep magma ocean environment. The behavior of the most highly siderophile elements (HSEs) during this process however, has remained enigmatic. Silicate run-products from HSE solubility experiments are commonly contaminated by dispersed metal inclusions that hinder the measurement of element concentrations in the melt. The resulting uncertainty over the true solubility and metal-silicate partitioning of these elements has made it difficult to predict their expected depletion in PUM. Recently, several studies have employed changes to the experimental design used for high pressure and temperature solubility experiments in order to suppress the formation of metal inclusions. The addition of Au (Re, Os, Ir, Ru experiments) or elemental Si (Pt experiments) to the sample acts to alter either the geometry or rate of sample reduction respectively, in order to avoid transient metal oversaturation of the silicate melt. This contribution outlines procedures for using the piston-cylinder and multi-anvil apparatus to conduct solubility and metal-silicate partitioning experiments respectively. A protocol is also described for the synthesis of uncontaminated run-products from HSE solubility experiments in which the oxygen fugacity is similar to that during terrestrial core-formation. Time-resolved LA-ICP-MS spectra are presented as evidence for the absence of metal-inclusions in run-products from earlier studies, and also confirm that the technique may be extended to investigate Ru. Examples are also given of how these data may be applied.

下面的实施例和讨论集中在实验确定的HSE溶解度硅酸盐熔点低˚FO 2。有关如何从多砧实验MSE和SSE分区的数据可以被用来限制在 P全面例子- 笔- ˚F澳芯金属偏析2的条件下，读者可参考的引用10 - 11 图7B-D显示背从典型的实验运行的产品散射电子图像。在包含Au的实验中，硅酸盐熔体之间的润湿性，金熔体和固体的HSE（再，锇，铱，钌）决定了?...

Watch this Scientific Journal Video about Metal-silicate Partitioning at High Pressure and Temperature: Experimental Methods and a Protocol to Suppress Highly Siderophile Element Inclusions at JoVE.co

Metal-silicate Partitioning at High Pressure and Temperature: Experimental Methods and a Protocol to Suppress Highly Siderophile Element Inclusions

We present a procedure to determine the metal-silicate partitioning of siderophile elements, emphasizing techniques that suppress the formation of metal inclusions in experiments for the noble metals. The results of these experiments are used to demonstrate the effect of core-formation on the highly siderophile element composition of the mantle.

金属硅酸盐分区在高压和高温：实验方法和协议，以抑制高亲铁元素元素夹杂物

Estimates of the primitive upper mantle (PUM) composition reveal a depletion in many of the siderophile (iron-loving) elements, thought to result from ...

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12.4K 次观看.  University of Toronto. We present a procedure to determine the metal-silicate partitioning of siderophile elements, emphasizing techniques that suppress the formation of metal inclusions in experiments for the noble metals. The results of these experiments are used to demonstrate the effect of core-formation on the highly siderophile element composition of the mantle.

视频: Metal-silicate Partitioning at High Pressure and Temperature: Experimental Methods and a Protocol to Suppress Highly Siderophile Element Inclusions

High-pressure Sapphire Cell for Phase Equilibria Measurements of CO2/Organic/Water Systems

The high pressure sapphire cell apparatus was constructed to visually determine the composition of multiphase systems without physical sampling. Specifically, the sapphire cell enables visual data collection from multiple loadings to solve a set of material balances to precisely determine phase composition. Ternary phase diagrams can then be established to determine the proportion of each component in each phase at a given condition. In principle, any ternary system can be studied although ternary systems (gas-liquid-liquid) are the specific examples discussed herein. For instance, the ternary THF-Water-CO2 system was studied at 25 and 40&#160;&#176;C and is described herein. Of key importance, this technique does not require sampling. Circumventing the possible disturbance of the system equilibrium upon sampling, inherent measurement errors, and technical difficulties of physically sampling under pressure is a significant benefit of this technique. Perhaps as important, the sapphire cell also enables the direct visual observation of the phase behavior. In fact, as the CO2 pressure is increased, the homogeneous THF-Water solution phase splits at about 2 MPa. With this technique, it was possible to easily and clearly observe the cloud point and determine the composition of the newly formed phases as a function of pressure.
The data acquired with the sapphire cell technique can be used for many applications. In our case, we measured swelling and composition for tunable solvents, like gas-expanded liquids, gas-expanded ionic liquids and Organic Aqueous Tunable Systems (OATS)1-4. For the latest system, OATS, the high-pressure sapphire cell enabled the study of (1) phase behavior as a function of pressure and temperature, (2) composition of each phase (gas-liquid-liquid) as a function of pressure and temperature and (3) catalyst partitioning in the two liquid phases as a function of pressure and composition. Finally, the sapphire cell is an especially effective tool to gather accurate and reproducible measurements in a timely fashion.

High-pressure Sapphire Cell for Phase Equilibria Measurements of CO2/Organic/Water Systems

The high pressure sapphire cell apparatus is a unique tool to study, without sampling, phase behavior under a wide range of pressures. Using a cathetometer, very precise volume measurements can be recorded to measure liquid expansion and phase composition. Thus, this synthetic method enables the study of (1) phase equilibria of multi-component mixtures and (2) the partition behavior of catalyst or model compounds as a function of pressure.

高压蓝宝石细胞对CO的相平衡测量<sub&gt; 2</sub&gt; /有机/水系统

The high pressure sapphire cell apparatus was constructed to visually determine the composition of multiphase systems without physical sampling. ...

科研

化学

Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization

We demonstrate a method for high-throughput catalyst screening using a parallel pressure reactor starting from the initial synthesis of a nickel &#945;-diimine ethylene polymerization catalyst. Initial polymerizations with the catalyst lead to optimized reaction conditions, including catalyst concentration, ethylene pressure and reaction time. Using gas-uptake data for these reactions, a procedure to calculate the initial rate of propagation (kp) is presented. Using the optimized conditions, the ability of the nickel &#945;-diimine polymerization catalyst to undergo chain transfer with diethylzinc (ZnEt2) during ethylene polymerization was investigated. A procedure to assess the ability of the catalyst to undergo chain transfer (from molecular weight and 13C NMR data), calculate the degree of chain transfer, and calculate chain transfer rates (ke) is presented.

A protocol for the high-throughput analysis of polymerization catalyst, chain transfer polymerizations, polyethylene characterization, and reaction kinetic analysis is presented.

乙烯聚合中使用并联电抗器的压力和链转移聚合的动力学分析

We demonstrate a method for high-throughput catalyst screening using a parallel pressure reactor starting from the initial synthesis of a nickel ...

Preparation of Carbon Nanosheets at Room Temperature

Amphiphilic molecules equipped with a reactive, carbon-rich "oligoyne" segment consisting of conjugated carbon-carbon triple bonds self-assemble into defined aggregates in aqueous media and at the air-water interface. In the aggregated state, the oligoynes can then be carbonized under mild conditions while preserving the morphology and the embedded chemical functionalization. This novel approach provides direct access to functionalized carbon nanomaterials. In this article, we present a synthetic approach that allows us to prepare hexayne carboxylate amphiphiles as carbon-rich siblings of typical fatty acid esters through a series of repeated bromination and Negishi-type cross-coupling reactions. The obtained compounds are designed to self-assemble into monolayers at the air-water interface, and we show how this can be achieved in a Langmuir trough. Thus, compression of the molecules at the air-water interface triggers the film formation and leads to a densely packed layer of the molecules. The complete carbonization of the films at the air-water interface is then accomplished by cross-linking of the hexayne layer at room temperature, using UV irradiation as a mild external stimulus. The changes in the layer during this process can be monitored with the help of infrared reflection-absorption spectroscopy and Brewster angle microscopy. Moreover, a transfer of the carbonized films onto solid substrates by the Langmuir-Blodgett technique has enabled us to prove that they were carbon nanosheets with lateral dimensions on the order of centimeters.

We present the synthesis of an amphiphilic hexayne and its use in the preparation of carbon nanosheets at the air-water interface from a self-assembled monolayer of these reactive, carbon-rich molecular precursors.

碳纳米片在室温下准备

Amphiphilic molecules equipped with a reactive, carbon-rich "oligoyne" segment consisting of conjugated carbon-carbon triple bonds self-assemble into ...

Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives

Molecules bearing trifluoromethoxy (OCF3) group often show desired pharmacological and biological properties. However, facile synthesis of trifluoromethoxylated aromatic compounds remains a formidable challenge in organic synthesis. Conventional approaches often suffer from poor substrate scope, or require use of highly toxic, difficult-to-handle, and/or thermally labile reagents. Herein, we report a user-friendly protocol for the synthesis of methyl 4-acetamido-3-(trifluoromethoxy)benzoate using 1-trifluoromethyl-1,2-benziodoxol-3(1H)-one (Togni reagent II). Treating methyl 4-(N-hydroxyacetamido)benzoate (1a) with Togni reagent II in the presence of a catalytic amount of cesium carbonate (Cs2CO3) in chloroform at RT afforded methyl 4-(N-(trifluoromethoxy)acetamido)benzoate (2a). This intermediate was then converted to the final product methyl 4-acetamido-3-(trifluoromethoxy)benzoate (3a) in nitromethane at 120 &#176;C. This procedure is general and can be applied to the synthesis of a broad spectrum of ortho-trifluoromethoxylated aniline derivatives, which could serve as useful synthetic building blocks for the discovery and development of new pharmaceuticals, agrochemicals, and functional materials.

Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives

An operationally simple procedure for the synthesis of ortho-trifluoromethoxylated aniline derivatives via a two-step sequence of O-trifluoromethylation of N-aryl-N-hydroxyacetamide followed by thermally induced intramolecular OCF3-migration is reported.

协议的合成<em&gt;邻</em&gt; -trifluoromethoxylated苯胺类化合物

Molecules bearing trifluoromethoxy (OCF3) group often show desired pharmacological and biological properties. However, facile synthesis of ...

Rapid High-throughput Species Identification of Botanical Material Using Direct Analysis in Real Time High Resolution Mass Spectrometry

We demonstrate that direct analysis in real time-high resolution mass spectrometry can be used to produce mass spectral profiles of botanical material, and that these chemical fingerprints can be used for plant species identification. The mass spectral data can be acquired rapidly and in a high throughput manner without the need for sample extraction, derivatization or pH adjustment steps. The use of this technique bypasses challenges presented by more conventional techniques including lengthy chromatography analysis times and resource intensive methods. The high throughput capabilities of the direct analysis in real time-high resolution mass spectrometry protocol, coupled with multivariate statistical analysis processing of the data, provide not only class characterization of plants, but also yield species and varietal information. Here, the technique is demonstrated with two psychoactive plant products, Mitragyna speciosa (Kratom) and Datura (Jimsonweed), which were subjected to direct analysis in real time-high resolution mass spectrometry followed by statistical analysis processing of the mass spectral data. The application of these tools in tandem enabled the plant materials to be rapidly identified at the level of variety and species.

A method for species identification of botanical material by direct analysis in real time-high resolution mass spectrometry and multivariate statistical analysis is presented.

植物材料的快速高通量物种鉴定实时高分辨质谱法直接分析

We demonstrate that direct analysis in real time-high resolution mass spectrometry can be used to produce mass spectral profiles of botanical material, ...

High Pressure Single Crystal Diffraction at PX^2

In this report we describe detailed procedures for carrying out single crystal X-ray diffraction experiments with a diamond anvil cell (DAC) at the GSECARS 13-BM-C beamline at the Advanced Photon Source. The DAC program at 13-BM-C is part of the Partnership for Extreme Xtallography (PX^2) project. BX-90 type DACs with conical-type diamond anvils and backing plates are recommended for these experiments. The sample chamber should be loaded with noble gas to maintain a hydrostatic pressure environment. The sample is aligned to the rotation center of the diffraction goniometer. The MARCCD area detector is calibrated with a powder diffraction pattern from LaB6. The sample diffraction peaks are analyzed with the ATREX software program, and are then indexed with the RSV software program. RSV is used to refine the UB matrix of the single crystal, and with this information and the peak prediction function, more diffraction peaks can be located. Representative single crystal diffraction data from an omphacite (Ca0.51Na0.48)(Mg0.44Al0.44Fe2+0.14Fe3+0.02)Si2O6 sample were collected. Analysis of the data gave a monoclinic lattice with P2/n space group at 0.35 GPa, and the lattice parameters were found to be: a = 9.496 &#177;0.006 &#197;, b = 8.761 &#177;0.004 &#197;, c = 5.248 &#177;0.001 &#197;, &#946; = 105.06 &#177;0.03&#186;, &#945; = &#947; = 90&#186;.

In this report, we describe detailed procedures for carrying out single crystal X-ray diffraction experiments with a diamond anvil cell at the GSECARS 13-BM-C beamline at the Advanced Photon Source. ATREX and RSV programs are used to analyze the data.

高压单晶衍射PX ^ 2

In this report we describe detailed procedures for carrying out single crystal X-ray diffraction experiments with a diamond anvil cell (DAC) at the ...

Non-equilibrium Microwave Plasma for Efficient High Temperature Chemistry

A flowing microwave plasma based methodology for converting electric energy into internal and/or translational modes of stable molecules with the purpose of efficiently driving non-equilibrium chemistry is discussed. The advantage of a flowing plasma reactor is that continuous chemical processes can be driven with the flexibility of startup times in the seconds timescale. The plasma approach is generically suitable for conversion/activation of stable molecules such as CO2, N2 and CH4. Here the reduction of CO2 to CO is used as a model system: the complementary diagnostics illustrate how a baseline thermodynamic equilibrium conversion can be exceeded by the intrinsic non-equilibrium from high vibrational excitation. Laser (Rayleigh) scattering is used to measure the reactor temperature and Fourier Transform Infrared Spectroscopy (FTIR) to characterize in situ internal (vibrational) excitation as well as the effluent composition to monitor conversion and selectivity.

This article describes a flowing microwave reactor that is used to drive efficient non-equilibrium chemistry for the application of conversion/activation of stable molecules such as CO2, N2 and CH4. The goal of the procedure described here is to measure the in situ gas temperature and gas conversion.

用于高效高温化学的非平衡微波等离子体

A flowing microwave plasma based methodology for converting electric energy into internal and/or translational modes of stable molecules with the purpose ...

A Straightforward Method for Glucosinolate Extraction and Analysis with High-pressure Liquid Chromatography (HPLC)

Glucosinolates are a well-studied and highly diverse class of natural plant compounds. They play important roles in plant resistance, rapeseed oil quality, food flavoring, and human health. The biological activity of glucosinolates is released upon tissue damage, when they are mixed with the enzyme myrosinase. This results in the formation of pungent and toxic breakdown products, such as isothiocyanates and nitriles. Currently, more than 130 structurally different glucosinolates have been identified. The chemical structure of the glucosinolate is an important determinant of the product that is formed, which in turn determines its biological activity. The latter may range from detrimental (e.g., progoitrin) to beneficial (e.g., glucoraphanin). Each glucosinolate-containing plant species has its own specific glucosinolate profile. For this reason, it is important to correctly identify and reliably quantify the different glucosinolates present in brassicaceous leaf, seed, and root crops or, for ecological studies, in their wild relatives. Here, we present a well-validated, targeted, and robust method to analyze glucosinolate profiles in a wide range of plant species and plant organs. Intact glucosinolates are extracted from ground plant materials with a methanol-water mixture at high temperatures to disable myrosinase activity. Thereafter, the resulting extract is brought onto an ion-exchange column for purification. After sulfatase treatment, the desulfoglucosinolates are eluted with water and the eluate is freeze-dried. The residue is taken up in an exact volume of water, which is analyzed by high-pressure liquid chromatography (HPLC) with a photodiode array (PDA) or ultraviolet (UV) detector. Detection and quantification are achieved by conducting comparisons of the retention times and UV spectra of commercial reference standards. The concentrations are calculated based on a sinigrin reference curve and well-established response factors. The advantages and disadvantages of this straightforward method, when compared to faster and more technologically advanced methods, are discussed here.

A Straightforward Method for Glucosinolate Extraction and Analysis with High-pressure Liquid Chromatography HPLC

Here, we describe in great detail an established and robust protocol for the extraction of glucosinolates from ground plant materials. After an on-column sulfatase treatment of the extracts, the desulfoglucosinolates are eluted and analyzed by high-pressure liquid chromatography.

简捷方法对硫甙的提取与分析用高压液相色谱法（HPLC）

Glucosinolates are a well-studied and highly diverse class of natural plant compounds. They play important roles in plant resistance, rapeseed oil ...

A Convenient Method for Extraction and Analysis with High-Pressure Liquid Chromatography of Catecholamine Neurotransmitters and Their Metabolites

The extraction and analysis of catecholamine neurotransmitters in biological fluids is of great importance in assessing nervous system function and related diseases, but their precise measurement is still a challenge. Many protocols have been described for neurotransmitter measurement by a variety of instruments, including high-pressure liquid chromatography (HPLC). However, there are shortcomings, such as complicated operation or hard-to-detect multiple targets, which cannot be avoided, and presently, the dominant analysis technique is still HPLC coupled with sensitive electrochemical or fluorimetric detection, due to its high sensitivity and good selectivity. Here, a detailed protocol is described for the pretreatment and detection of catecholamines with high pressure liquid chromatography with electrochemical detection (HPLC-ECD) in real urine samples of infants, using electrospun composite nanofibers composed of polymeric crown ether with polystyrene as adsorbent, also known as the packed-fiber solid phase extraction (PFSPE) method. We show how urine samples can be easily precleaned by a nanofiber-packed solid phase column, and how the analytes in the sample can be rapidly enriched, desorbed, and detected on an ECD system. PFSPE greatly simplifies the pretreatment procedures for biological samples, allowing for decreased time, expense, and reduction of the loss of targets. 
Overall, this work illustrates a simple and convenient protocol for solid-phase extraction coupled to an HPLC-ECD system for simultaneous determination of three monoamine neurotransmitters (norepinephrine (NE), epinephrine (E), dopamine (DA)) and two of their metabolites (3-methoxy-4-hydroxyphenylglycol (MHPG) and 3,4-dihydroxy-phenylacetic acid (DOPAC)) in infants' urine. The established protocol was applied to assess the differences of urinary catecholamines and their metabolites between high-risk infants with perinatal brain damage and healthy controls. Comparative analysis revealed a significant difference in urinary MHPG between the two groups, indicating that the catecholamine metabolites may be an important candidate marker for early diagnosis of cases at risk for brain damage in infants.

We present a convenient solid-phase extraction coupled to high-pressure liquid chromatography (HPLC) with electrochemical detection (ECD) for simultaneous determination of three monoamine neurotransmitters and two of their metabolites in infants' urine. We also identify the metabolite MHPG as a potential biomarker for the early diagnosis of brain damage for infants.

用高压液相色谱法提取和分析儿茶酚胺神经递质及其代谢物的简便方法

The extraction and analysis of catecholamine neurotransmitters in biological fluids is of great importance in assessing nervous system function and ...

Experimental Methods for Efficient Solar Hydrogen Production in Microgravity Environment

Long-term space flights and cis-lunar research platforms require a sustainable and light life-support hardware which can be reliably employed outside the Earth's atmosphere. So-called 'solar fuel' devices, currently developed for terrestrial applications in the quest for realizing a sustainable energy economy on Earth, provide promising alternative systems to existing air-revitalization units employed on the International Space Station (ISS) through photoelectrochemical water-splitting and hydrogen production. One obstacle for water (photo-) electrolysis in reduced gravity environments is the absence of buoyancy and the consequential, hindered gas bubble release from the electrode surface. This causes the formation of gas bubble froth layers in proximity to the electrode surface, leading to an increase in ohmic resistance and cell-efficiency loss due to reduced mass transfer of substrates and products to and from the electrode. Recently, we have demonstrated efficient solar hydrogen production in microgravity environment, using an integrated semiconductor-electrocatalyst system with p-type indium phosphide as the light-absorber and a rhodium electrocatalyst. By nanostructuring the electrocatalyst using shadow nanosphere lithography and thereby creating catalytic 'hot spots' on the photoelectrode surface, we could overcome gas bubble coalescence and mass transfer limitations and demonstrated efficient hydrogen production at high current densities in reduced gravitation. Here, the experimental details are described for the preparations of these nanostructured devices and further on, the procedure for their testing in microgravity environment, realized at the Bremen Drop Tower during 9.3 s of free fall.

Efficient solar-hydrogen production has recently been realized on functionalized semiconductor-electrocatalyst systems in a photoelectrochemical half-cell in microgravity environment at the Bremen Drop Tower. Here, we report the experimental procedures for manufacturing the semiconductor-electrocatalyst device, details of the experimental set-up in the drop capsule and the experimental sequence during free fall.

微重力环境下高效太阳能氢气生产的实验方法

Long-term space flights and cis-lunar research platforms require a sustainable and light life-support hardware which can be reliably employed outside the ...