我们感谢亚利桑那州立大学的 H.O.G. 小组制定了这些热液实验的初步方法, 特别是感谢我. 古尔德、e. 休克、l. 威廉斯、c. Glein、h. Hartnett、k. 费克图、鲁滨逊和 c. Bockisch, 他们指导和帮助。从奥克兰大学到 z 杨的创业基金资助了他和 x。

1. 制备热液试验样品
<ol><li>选择石英或石英玻璃管的尺寸,如2 毫米内径 (ID) x 6 毫米外径 (外径) 或6毫米 x 12 毫米外径, 并确定使用的有机化合物和矿物质的数量。在这项工作中, 硝基苯和磁铁矿的数量 (Fe3O4) 加载到二氧化硅管 (如2 毫米 ID x 6 毫米外径) 分别为3.0 µL 和13.9 毫克。 注: 大口径管允许材料更容易加载, 但需要更多的管道密封工作。</li>
	<li>用管子切割机将干净的石英玻璃管切成30厘米长的小块。密封的一端的管关闭使用氢氧焰火炬与适当的火焰头。 注意事项: 遵循使用氢氧焰火炬的安全程序。</li>
	<li>在0.1 毫克天平上 (如果它是实心的) 将起始有机化合物的预定量称重, 并使用称重纸将其转移到二氧化硅玻璃管中。如果化合物是液体 (例如, 硝基苯在这种情况下), 使用微升注射器 (例如, 10 µL) 把它转移到小二氧化硅管。通过巴斯德吸管将称重矿物加入硅胶管, 然后加入去离子和脱氧水 (如0.3 毫升)。用 18.2 MΩ·cm 去离子水, deoxygenate 超声波。</li>
	<li>用闭式阀门将硅胶管连接至真空线 (〜1厘米的 ID)。将管子浸入装满液氮的杜瓦瓶中, 浸泡3分钟, 直到有机物和水完全结冰。 注意事项: 按照安全规程转移和使用液氮。</li>
	<li>当管子停留在液氮中时, 打开真空阀, 从管子顶部卸下空气。 注: 此过程应持续到真空泵压力表上的压力降至 100 mtorr 以下。</li>
	<li>关掉阀门, 从液氮中取出管子, 让管子预热到室温。轻轻地敲击管子底部, 将剩余的气泡从溶液中释放到顶空。</li>
	<li>重复上述冷冻泵-解冻循环两次, 并保持管在液氮前密封的另一端的管。关闭真空线, 使用氢氧焰火焰, 使整个管关闭。 注: 当管道进行热液实验时, 由于液态水的膨胀, 管的顶空体积会降低。例如, 水的密度减少约30% 从室温到300摄氏度。在封管时计算并留下足够的顶空容积。</li>
</ol>2. 建立热液实验
<ol><li>密封步骤后, 将硅胶管放入小钢管 (长度为30厘米, 直径为1.5 厘米), 用松散的螺钉盖, 以防止管道内任何压力建筑物或管道损坏。</li>
	<li>把管子放在一个井温控制的炉子或烤箱里, 加热到所需的温度 (例如, 150 摄氏度)。在烤箱内使用热电偶, 通过热液反应来监测温度。</li>
	<li>当反应时间到达 (例如,在这工作中的2小时), 快速地把管子放进冰水浴中, 使硅管淬火。 注: 淬火过程需不到1分钟冷却至室温, 避免潜在的逆行反应。</li>
</ol>3. 实验后分析样品
<ol><li>使用管刀打开硅胶管, 并迅速将所有产品 (例如, 小二氧化硅管中的0.3 毫升) 转换成10毫升的玻璃瓶, 使用巴斯德吸管。</li>
	<li>用3毫升二氯甲烷 (DCM) 溶液提取有机产物, 其中含有8.8 毫米烷基作为气相色谱 (GC) 的内部标准。把瓶子盖上, 用手摇动2分钟, 然后将它旋转1分钟。 注: 这有助于促进有机产物的萃取进入有机相中。同时, 用 DCM 冲洗硅胶管的转移吸管和内壁, 确保产品的回收。对于含矿物质含量较高的样品, 油脂实验在 DCM 溶液中进行比较, 以更好地提取。</li>
	<li>允许矿物颗粒在萃取液中安定下来 (即, DCM 与烷基) 为5分钟. 使用巴斯德吸管小心地将1毫升的样品从 DCM 层 (即底部层) 转移到 GC 瓶中。</li>
	<li>用聚毛细管柱 (如5% diphenyl/95%dimethylsiloxane) 和火焰电离探测器对有机产物的分布进行分析。设置 GC 烤箱与程序开始在50°c 和举行8分钟, 增加10°c/分钟到220°c 和举行10分钟, 增加20°c/分钟300°c 和举行5分钟. 将喷油器温度设置为300摄氏度。 注: GC 程序需要根据所分析的有机化合物类型进行更改。</li>
	<li>通过将分析物的峰值面积比与所分析物的浓度进行绘制, 建立 GC 校准曲线。</li>
	<li>根据反应前后起始有机物的浓度计算反应转化,即conversion% = ([初始]-[最终]) ⁄ [初始] ×100%。使用转换来确定矿物是否有利于或减慢热液有机转换。</li>
</ol>

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作者没有什么可透露的。

本研究以硝基苯为矿物磁铁矿为例, 说明如何评价矿物对热液有机反应的影响。虽然在小型石英玻璃管中进行了实验, 但在磁铁矿实验中观察到了高重现性的结果,即30.3 1.4% 的硝基苯转化, 表明了该热液协议。在无矿物实验中, 硝基苯的转化率为 5.2, 为 2.1%, 表现出的重现性比矿物试验低。在无矿物实验中, 相对较高的不确定性可能是由于起始材料的低转换, 考虑到小管中所用样品的µL (或 mg)。?...

水热环境 (即高温和高压下的水介质) 在地球上无处不在。有机化合物的热液化学在多种地球化学环境中起着重要作用, 如有机沉积盆地、油气藏和深生物圈1、2、3。热液系统中的有机碳转化不仅发生在纯净的水介质中, 而且还与溶解或固体无机材料 (如富含地球的矿物) 相结合。矿物被发现对各种有机化合物的水热反应性有显著的选择性影响,1、4、5 , 但如何识别复杂的热液体系中的矿物效应仍然是一个挑战。本研究的目的是为研究矿物对热液有机反应的影响提供一个相对简单的实验协议。
水热反应的实验室研究传统上使用的是由金, 钛, 或不锈钢6,7,8,9制成的坚固的反应堆。例如, 金袋或胶囊已经得到了良好的使用, 因为黄金是灵活的, 它允许样品压力由外部加压水控制, 从而避免在样品内产生汽相。然而, 这些反应堆是昂贵的, 可能会与潜在的金属催化效应10。因此, 为这些热液实验寻找一种成本低但可靠性高的替代方法势在必行。
近年来, 石英或熔融石英玻璃的反应管越来越多地应用于水热实验11,12,13。与贵重的金或钛相比, 石英或二氧化硅玻璃的价格要便宜得多, 而且材料也很结实。更重要的是, 石英管显示的催化效果很少, 并且可以像金一样惰性的热液反应11,14。在本协议中, 我们描述了在厚壁石英管中进行小规模热液有机矿物实验的一般方法。我们提出一个例子实验使用模型化合物 (即硝基苯) 在存在/没有铁氧化物矿物 (即磁铁矿) 在150°c 热液溶液, 为了显示矿物作用, 并且证明此方法的有效性。

<table><tbody><tr><td>&lt;strong&gt;Chemicals:&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>Dichloromethane</td><td>VWR</td><td>BDH23373.400</td><td></td></tr><tr><td>Dodecane</td><td>Sigma-Aldrich</td><td>297879</td><td></td></tr><tr><td>Nitrobenzene</td><td>Sigma-Aldrich</td><td>252379</td><td></td></tr><tr><td>Fe&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt;</td><td>Sigma-Aldrich</td><td>310050</td><td></td></tr><tr><td>Fe&lt;sub&gt;3&lt;/sub&gt;O&lt;sub&gt;4&lt;/sub&gt;</td><td>Sigma-Aldrich</td><td>637106</td><td></td></tr><tr><td>&lt;strong&gt;Supplies:&lt;/strong&gt;</td><td></td><td></td><td></td></tr><tr><td>Silica tube</td><td></td><td></td><td></td></tr><tr><td>Vacuum pump</td><td>WELCH</td><td>2546B-01</td><td></td></tr><tr><td>Vacuum line</td><td></td><td></td><td></td></tr><tr><td>Oven</td><td>Hewlett Packard</td><td>5890</td><td></td></tr><tr><td>Thermocouple</td><td>BENETECH</td><td>GM1312</td><td></td></tr><tr><td>Gas chromatography</td><td>Agilent</td><td>7820A</td><td></td></tr></tbody></table>

an experimental protocol for studying mineral effects on organic hydrothermal transformations

有机-矿物相互作用在热液环境中广泛发生, 如温泉、陆地间歇泉和深海热液喷口。矿物在许多热液有机地球化学过程中的作用是至关重要的。传统的热液方法, 包括使用由金、钛、铂或不锈钢制成的反应堆, 通常与高成本或不想要的金属催化效应有关。近年来, 在水热实验中使用经济高效、惰性石英或熔融二氧化硅玻璃管的趋势越来越大。在此, 我们提供了一种在石英管中进行有机矿物热液实验的协议, 并描述了样品制备、实验装置、产品分离和定量分析的基本步骤。我们还演示了一个实验使用的一个模型有机化合物, 硝基苯, 以显示的影响, 含铁矿物, 磁铁矿, 对其降解在特定的水热条件下。该技术可应用于比较简单的实验室系统中复杂的有机矿物热液相互作用的研究。

为了演示如何使用这种方法来研究热液有机矿物相互作用, 一个简单的实验使用了一个模型化合物, 硝基苯, 用矿物磁铁矿 (Fe3O4) 在热液条件150°c 和52小时的酒吧。为了显示矿物效应, 在同一热液条件下, 还进行了无矿物硝基苯的实验。如图 1a所示, 在热液实验之前, 两个硅胶管是按照协议进行的。没有矿物的密封管是明确的, 与磁铁矿?...

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

An Experimental Protocol for Studying Mineral Effects on Organic Hydrothermal Transformations

地球丰富的矿物在天然热液系统中起着重要的作用。本文介绍了水热条件下有机矿物相互作用实验研究的一种可靠、经济有效的方法。

研究矿物对有机热液转化影响的实验协议

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

an-experimental-protocol-for-studying-mineral-effects-on-organic

Research

JoVE Journal

Environment

5.6K 次观看.  Oakland University. 地球丰富的矿物在天然热液系统中起着重要的作用。本文介绍了水热条件下有机矿物相互作用实验研究的一种可靠、经济有效的方法。

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

Experimental Protocol for Manipulating Plant-induced Soil Heterogeneity

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

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

用于操纵植物诱导土壤异质性的实验协议

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

科研

环境科学

Laboratory Simulation of an Iron(II)-rich Precambrian Marine Upwelling System to Explore the Growth of Photosynthetic Bacteria

A conventional concept for the deposition of some Precambrian Banded Iron Formations (BIF) proceeds on the assumption that ferrous iron [Fe(II)] upwelling from hydrothermal sources in the Precambrian ocean was oxidized by molecular oxygen [O2] produced by cyanobacteria. The oldest BIFs, deposited prior to the Great Oxidation Event (GOE) at about 2.4 billion years (Gy) ago, could have formed by direct oxidation of Fe(II) by anoxygenic photoferrotrophs under anoxic conditions. As a method for testing the geochemical and mineralogical patterns that develop under different biological scenarios, we designed a 40 cm long vertical flow-through column to simulate an anoxic Fe(II)-rich marine upwelling system representative of an ancient ocean on a lab scale. The cylinder was packed with a porous glass bead matrix to stabilize the geochemical gradients, and liquid samples for iron quantification could be taken throughout the water column. Dissolved oxygen was detected non-invasively via optodes from the outside. Results from biotic experiments that involved upwelling fluxes of Fe(II) from the bottom, a distinct light gradient from top, and cyanobacteria present in the water column, show clear evidence for the formation of Fe(III) mineral precipitates and development of a chemocline between Fe(II) and O2. This column allows us to test hypotheses for the formation of the BIFs by culturing cyanobacteria (and in the future photoferrotrophs) under simulated marine Precambrian conditions. Furthermore we hypothesize that our column concept allows for the simulation of various chemical and physical environments &#8212; including shallow marine or lacustrine sediments.

Laboratory Simulation of an IronII-rich Precambrian Marine Upwelling System to Explore the Growth of Photosynthetic Bacteria

We simulated a Precambrian ferruginous marine upwelling system in a lab-scale vertical flow-through column. The goal was to understand how geochemical profiles of O2 and Fe(II) evolve as cyanobacteria produce O2. The results show the establishment of a chemocline due to Fe(II) oxidation by photosynthetically produced O2.

一个铁（II）的实验室模拟的前寒武纪富海洋上升流系统探索光合细菌生长

A conventional concept for the deposition of some Precambrian Banded Iron Formations (BIF) proceeds on the assumption that ferrous iron [Fe(II)] upwelling ...

Soil Lysimeter Excavation for Coupled Hydrological, Geochemical, and Microbiological Investigations

Studying co-evolution of hydrological and biogeochemical processes in the subsurface of natural landscapes can enhance the understanding of coupled Earth-system processes. Such knowledge is imperative in improving predictions of hydro-biogeochemical cycles, especially under climate change scenarios. We present an experimental method, designed to capture sub-surface heterogeneity of an initially homogeneous soil system. This method is based on destructive sampling of a soil lysimeter designed to simulate a small-scale hillslope. A weighing lysimeter of one cubic meter capacity was divided into sections (voxels) and was excavated layer-by-layer, with sub samples being collected from each voxel. The excavation procedure was aimed at detecting the incipient heterogeneity of the system by focusing on the spatial assessment of hydrological, geochemical, and microbiological properties of the soil. Representative results of a few physicochemical variables tested show the development of heterogeneity. Additional work to test interactions between hydrological, geochemical, and microbiological signatures is planned to interpret the observed patterns. Our study also demonstrates the possibility of carrying out similar excavations in order to observe and quantify different aspects of soil-development under varying environmental conditions and scale.

This study presents an excavation method for investigating subsurface hydrological, geochemical, and microbiological heterogeneity of a soil lysimeter. The lysimeter simulates an artificial hillslope which was initially under homogeneous condition and had been subjected to approximately 5,000 mm of water over eight cycles of irrigation in an 18-month period.

土壤蒸渗仪开挖加之水文，地球化学和微生物调查

Studying co-evolution of hydrological and biogeochemical processes in the subsurface of natural landscapes can enhance the understanding of coupled ...

Chemical Gardens as Flow-through Reactors Simulating Natural Hydrothermal Systems

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

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

化工园为直通式反应器模拟自然热液系统

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

化学

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

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

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

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

用于研究铁 (氧) 氢氧化物、微量元素和细菌之间厌氧生物地球化学相互作用的实验柱装置

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

Simulation of Early Earth Hydrothermal Chimneys in a Thermal Gradient Environment

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

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

热梯度环境中早期地球热液烟囱的模拟

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

Bioprospecting of Extremophilic Microorganisms to Address Environmental Pollution

Geothermal springs are rich in various metal ions due to the interaction between rock and water that takes place in the deep aquifer. Moreover, due to seasonality variation in pH and temperature, fluctuation in element composition is periodically observed within these extreme environments, influencing the environmental microbial communities. Extremophilic microorganisms that thrive in volcanic thermal vents have developed resistance mechanisms to handle several metal ions present in the environment, thus taking part to complex metal biogeochemical cycles. Moreover, extremophiles and their products have found an extensive foothold in the market, and this holds true especially for their enzymes. In this context, their characterization is functional to the development of biosystems and bioprocesses for environmental monitoring and bioremediation. To date, the isolation and cultivation under laboratory conditions of extremophilic microorganisms still represent a bottleneck for fully exploiting their biotechnological potential. This work describes a streamlined protocol for the isolation of thermophilic microorganisms from hot springs as well as their genotypical and phenotypical identification through the following steps: (1) Sampling of microorganisms from geothermal sites ("Pisciarelli", a volcanic area of Campi Flegrei in Naples, Italy); (2) Isolation of heavy metal resistant microorganisms; (3) Identification of microbial isolates; (4) Phenotypical characterization of the isolates. The methodologies described in this work might be generally applied also for the isolation of microorganisms from other extreme environments.

The isolation of heavy metal-resistant microbes from geothermal springs is a hot topic for the development of bioremediation and environmental monitoring biosystems. This study provides a methodological approach for isolating and identifying heavy metal tolerant bacteria from hot springs.

极端微生物的生物勘探以解决环境污染问题

Geothermal springs are rich in various metal ions due to the interaction between rock and water that takes place in the deep aquifer. Moreover, due to ...

Transformation of Organic Household Leftovers into a Peat Substitute

A two-step procedure is described for the synthesis of a carbon material with a similar composition and properties as peat. The produced hydrochar is made suitable for agricultural applications by removing plant growing inhibitory substances. Wet household waste such as fruit peel, coffee grounds, inedible vegetable parts, or wet lignocellulosic material in general, are treated in presence of water at 215 &#x00B0;C and 21 bar in an autoclave, i.e., by hydrothermal carbonization. All these leftovers have a considerable water content of up to 90 weight % (wt%). Adding water extends the procedure to drier materials such as nutshells or even garden prunings and compostable polymers, i.e., the plastic bag for collection of the leftovers.
Usually, the resulting carbon material, called hydrochar, produces a negative effect on plant growth when added to soil. It is supposed that this effect is caused by adsorbed phytotoxic compounds. A simple post-treatment under inert atmosphere (absence of oxygen) at 275 &#x00B0;C removes these substances. Therefore, the raw hydrochar is placed on a glass frit of a vertical tubular quartz reactor. A nitrogen gas flow is applied in down-flow direction. The tube is heated to the desired temperature by means of a heating mantle for up to one hour.
The success of the thermal treatment is easily quantified by thermogravimetry (TG), carried out in air. A weight loss is determined when the temperature of 275 &#x00B0;C is reached, since volatile content is desorbed. Its amount is reduced in the final material, in comparison to the untreated hydrochar.
The two-step treatment converts household leftovers, including compostable bags employed for their collection, into a carbon material that may serve as plant growth promoter and, at the same time, as a carbon sink for climate change mitigation.

A protocol for hydrothermal carbonization of vegetable food waste in an autoclave is presented, with subsequent dry thermal treatment at 275 &#x00B0;C in a continuous flow reactor desorbing volatile organic substances. The aim is to produce a carbon material suitable as soil amendment product or substrate component.

将有机家庭剩剩食品转化为泥炭替代品

A two-step procedure is described for the synthesis of a carbon material with a similar composition and properties as peat. The produced hydrochar is made ...

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

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

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

使用柔性金钛反应细胞在地下生物采矿环境中模拟压力依赖微生物活性

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

工程学

基于膦酸盐的 MOF 的合成和发现：一种溶热方法

Discovery and Synthesis Optimization of Isoreticular Al(III) Phosphonate-Based Metal-Organic Framework Compounds Using High-Throughput Methods

High-throughput (HT) methods are an important tool for the fast and efficient screening of synthesis parameters and the discovery of new materials. This manuscript describes the synthesis of metal-organic frameworks (MOFs) from solution using an HT reactor system, resulting in the discovery of various phosphonate-based MOFs of the composition [Al2H12-x(PMP)3]Clx&#8729;6H2O (H4PMP = N,N &#39;-piperazine bis(methylenephosphonic acid)) for x = 4, 6, denoted as Al-CAU-60-xHCl, containing trivalent aluminum ions. This was accomplished under solvothermal reaction conditions by systematically screening the impact of the molar ratio of the linker to the metal and the pH of the reaction mixture on the product formation. The protocol for the HT investigation includes six steps: a) synthesis planning (DOE = design of&#160;experiment) within the HT methodology, b) dosing and working with in-house developed HT reactors, c) solvothermal synthesis, d) synthesis workup using in-house developed filtration blocks, e) characterization by HT powder X-ray diffraction, and f) evaluation of the data. The HT methodology was first used to study the influence of acidity on the product formation, leading to the discovery of Al-CAU-60&#8729;xHCl (x = 4 or 6).

作者聚焦：加速微孔材料化学的发现 

The targeted synthesis of new metal-organic frameworks (MOFs) is difficult, and their discovery depends on the knowledge and creativity of the chemist. High-throughput methods allow complex synthetic parameter fields to be explored quickly and efficiently, accelerating the process of finding crystalline compounds and identifying synthetic and structural trends.

基于高通量方法的等网状Al（III）膦酸盐基金属有机骨架化合物的发现与合成优化

High-throughput (HT) methods are an important tool for the fast and efficient screening of synthesis parameters and the discovery of new materials. This ...