我々 はこれらの熱水合成実験の初期の方法論を開発するためアリゾナ州立大学の hog でグループを感謝し、特に、i. グールド、E. ショック、・ ウィリアムス、C. Glein、h. ハートネット、k. Fecteau、・ ロビンソンと C. Bockisch に感謝のガイダンスと参考に支援。Z のヤンと X. Fu Z のヤンにオークランド大学からスタートアップ資金によって資金を供給されました。

1. 熱水実験用サンプルを準備します。
<ol><li>水晶や石英ガラス管、例えば、 2 mm 内径 (ID) x 6 mm 外径 (OD) または ID x 12 が mm 外径 6 mm のサイズを選択し、有機物と使用する鉱物の量を定めます。この作品でニトロ ベンゼンと (例えば、 2 mm ID x 6 mm 外径) 石英管にロードする磁鉄鉱 (Fe3O4) の量は 3.0 μ L 13.9 mg それぞれです。 注: 大口径管材料の容易にロードするが管のシーリングのより多くの努力を必要とします。</li>
	<li>~ 30 cm と小さな断片にきれいな石英ガラス管をチューブ カッターを使用して長さにカットします。酸水素トーチを用いた適切な炎頭を閉じた管の一方の端をシールします。 注意: 酸水素のトーチを使用するため安全手順に従います。</li>
	<li>0.1 mg スケール (固体の場合) のバランスをとるし、秤量紙を用いた石英ガラス管に転送の開始の有機化合物の所定量の重量を量る。場合は、化合物は、液体 (例えば、この場合ニトロ ベンゼン)、小さな石英管にそれを転送する 1 マイクロリットル注射器 (例えば10 μ L) を使用します。パスツール ピペットで石英管に重量を量られた鉱物を追加し、脱・脱酸素水 (例えば、0.3 mL) を追加します。18.2 MΩ·cm 脱イオン水を使用し、超音波処理による deoxygenate。</li>
	<li>閉鎖弁付け真空ライン (~ 1 cm ID) に石英管を接続します。有機物と水が完全に冷凍されるまで 〜 3 分間液体窒素で満たされたデュワー フラスコで管を浸します。 注意: 転送し、液体窒素を使用するため安全手順に従います。</li>
	<li>チューブを液体窒素に浸漬に、ままとき真空バルブを開き、チューブのヘッドから空気を除去します。 注: このプロセスは、圧力が真空ポンプの圧力ゲージの 100 mtorr を下回るまで続くはず。</li>
	<li>バルブをオフ、液体窒素からチューブを削除し、室温まで温チューブ。ヘッド スペースに解決策から残りの空気の泡を解放する管の底を軽くたたきます。</li>
	<li>さらに 2 回の上記の凍結-融解性ポンプのサイクルを繰り返し、チューブのもう一方の端を密封する前に液体窒素でチューブを維持します。真空ラインを閉じ、閉じた全体の管を作る酸水素火炎を使用します。 注: チューブは、熱水実験を受け、液体の水膨張管のヘッド スペース台数が減少します。水の密度が 300 ° c 程度室温から約 30% を削減できるなど、計算し、管を密封した場合十分なヘッド ボリュームを残します。</li>
</ol>2. 熱水実験を設定します。
<ol><li>シールの手順後我慢シリカ チューブ小さなスチール パイプ (~ 30 cm の長さと直径 1.5 cm) に緩いねじキャップ、任意の圧力建物または管内管障害による損傷を防ぐために。</li>
	<li>よく恒温炉やオーブンでパイプを置き、所望の温度 (例えば、この仕事で 150 ° C) まで加熱します。水熱反応により温度を監視するのに炉内熱電対を使用します。</li>
	<li>(例えば、この作品で 2 h) 反応時間に達すると、すぐに、すばやく氷水風呂にパイプを置くことによって石英管を癒します。 注: 焼入プロセスは潜在的な逆行性反応を避け室温に冷却する 1 分未満かかります。</li>
</ol>3. 実験の後、サンプルを分析します。
<ol><li>チューブ カッターを使用して石英管を開き、パスツール ピペットを使用して 10 mL バイアルにすべての製品 (例えば、小さな石英管で ~0.3 mL) をすばやく転送します。</li>
	<li>ガスクロマトグラフィー (GC) 用内部標準として 8.8 mM ドデカンを含む 3 mL ジクロロ メタン (DCM) ソリューションとオーガニック製品を抽出します。キャップ バイアルとそれで手 2 分の渦 1 分間振る。 注: これはオーガニック有機相への抽出を容易にするのに役立ちます。また、製品の回復を確実に DCM の石英管の転送ピペットと内側の壁をすすいでください。ミネラル含量の高いサンプルより良い抽出の DCM ソリューションでそれらを超音波照射します。</li>
	<li>5 分使用して慎重に GC バイアルに DCM の層 (すなわち底層) から 〜 1 mL のサンプルを転送するパスツール ピペットの抽出液 (すなわちドデカンと DCM) に定住する鉱物粒子を許可します。</li>
	<li>ポリ毛細管カラム (例えば5 %diphenyl/95% ジメチルシロキサン) と炎イオン化検出器の GC を用いた有機製品の流通を分析します。50 ° c を開始、8 分間保持、220 ° C まで 10 ° C/分で増加し 10 分間保持、300 ° C まで 20 ° C/分で増加、300 ° C に 5 分セット インジェクター温度を保持するプログラムを GC オーブンを設定します。 注: を変更するために必要な GC プログラムは有機化合物の分析対象の種類に基づいています。</li>
	<li>GC 検を構築するには、試料の濃度と内部標準試料のピーク面積比をプロットします。</li>
	<li>前に、と後の反応、すなわち変換 % 有機原料の濃度に基づく反応換算 = ([初版]-[最終]) ⁄ [初期] × 100%。変換を使用すると、ミネラルを容易にまたは熱水有機変換が遅くかどうかを確認します。</li>
</ol>

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著者が明らかに何もありません。

本研究で我々 ニトロ ベンゼン ミネラル磁鉄鉱として使用例熱水有機反応における鉱物の影響を評価するのに方法をデモンストレーションします。小さな石英ガラス管で、実験を行い、再現性の高い結果がマグネタイトの実験、すなわち30.3 ± 1.4% ニトロ ベンゼンの変換、有効性と信頼性のあるこれを示唆しているので観察、熱水のプロトコル。なし鉱物の実験でニトロ ベンゼンの変?...

熱水環境 (すなわち、高温高圧の水溶液) 地球上至るところでされます。有機化合物の水熱化学は、有機堆積盆地、石油タンク、地下生物圏1,2,3などの地球化学的設定の広い範囲で重要な役割を果たしています。熱水系における有機炭素変換だけでなく地球豊富なミネラルなど溶存または固体の無機材料、でも純粋な水溶液で発生します。劇的に、選択的に影響を与える各種の有機化合物の水熱反応性鉱物が発見されているが、1,4、5複雑な熱水系におけるミネラルの効果を識別する方法課題として残っています。本研究の目的は、熱水有機反応に及ぼす鉱物を研究するための比較的簡単な実験プロトコルを提供することです。
水熱反応の実験的研究は伝統的にゴールド、チタンまたはステンレス鋼6,7,8,9から成っている堅牢な原子炉を使用します。たとえば、金の袋またはカプセル使用されている好意的、金は柔軟性ができ、サンプルの圧力、外部から水を加圧によって制御するサンプル中の気相の生成を避けますため。ただし、これらの原子炉は高価であり、潜在的な金属の触媒効果10と関連付けることができます。したがって、これらの熱水実験用低コスト、高い信頼性と別の方法を見つけることが不可欠です。
近年、水晶や石英ガラス製反応管は熱水実験11,12,13に多く適用されています。貴重な金やチタンと比較して、水晶や石英ガラスはまた強い材料がかなり安いです。もっと重大に、石英管ほとんどの触媒効果を示しているし、不活性にすることができます水熱反応11,14金として。このプロトコルではシリカの厚肉管の小規模の熱水有機鉱物実験を行うための一般的方法をについて説明します。デモンストレーションとしてミネラル効果を示すために 150 ° C の熱水溶液中の鉄酸化物鉱物 (すなわち磁鉄鉱) の有無でモデル化合物 (すなわち、ニトロ ベンゼン) を用いた例実験を提案する、このメソッドの有効性。

<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

土地、および深海の熱水噴出孔に間欠泉、温泉などの熱水環境下での有機・無機相互作用が広く行われます。ミネラルの役割は、多くの熱水の有機地球化学的プロセスで重要です。ゴールド、チタン、プラチナ、またはステンレス スチール製の原子炉を使用して含まれています、伝統的な熱水方法論は高コストまたは好ましくない金属触媒効果に通常関連付けられます。最近では、熱水実験で費用対効果や不活性の水晶や石英ガラス管を使用して成長傾向があります。ここでは、我々 は石英管内有機鉱物の熱水合成実験を遂行するためプロトコルを提供し、試料、実験装置、製品の分離と定量分析に不可欠な手順について述べる。モデル有機化合物、ニトロ ベンゼンを使用して特定の熱水条件下での分解に鉄を含む鉱物、マグネタイトの効果を表示する実験を紹介します。この手法は、比較的簡単な実験室システムにおける複雑な有機鉱物熱水相互作用に適用できます。

このアプローチを使用して熱水の有機・無機相互作用モデル化合物を用いた簡単な実験を研究する方法を示すためには、ニトロ ベンゼン、ミネラル磁鉄鉱 (Fe3O4) 150 ° C と 5 の水熱条件で行った2 h のバー。ミネラルの効果を見る、ミネラルなしのニトロ ベンゼンの実験も同じ熱水条件下で実施しました。図 1 aのように、2 つのシ...

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-豊富なミネラルは、天然の熱水系における重要な役割を果たします。ここでは、我々 は熱水条件下での有機・無機相互作用の実験的調査のため信頼性が高く、コスト効果の高い方法をについて説明します。

有機水熱変換のミネラル効果を研究するための実験プロトコル

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

Universidad San Sebastian

Research

JoVE Journal

Environment

5.6K ビュー.  Oakland University. 地球-豊富なミネラルは、天然の熱水系における重要な役割を果たします。ここでは、我々 は熱水条件下での有機・無機相互作用の実験的調査のため信頼性が高く、コスト効果の高い方法をについて説明します。

ビデオ: 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.

の操作植物に誘導される土壌の不均一性のための実験プロトコール

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

環境学

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.

光合成細菌の増殖を探検する鉄（II）リッチ先カンブリア時代マリン湧昇システムの実験室でのシミュレーション

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.

結合水文学、地球化学、および微生物学的調査のための土壌ライシメータ発掘

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.

ケミカル・ガーデンフロースルーリアクターのシミュレーション自然熱水系など

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.

(オキシ) 鉄の水酸化物、微量元素、細菌の嫌気性生物地球化学的相互作用を研究するため実験的列の設定

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.

熱勾配環境における初期の地球熱水煙突のシミュレーション

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.

環境汚染に対処するための極限環境微生物のバイオプロスペクティング

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.

有機家庭の残り物を泥炭代替品に変える

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.

フレキシブル金チタン反応細胞を用いて、地下バイオマイニングのコンテキストにおける圧力依存微生物活性をシミュレート

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

工学

ホスホネート基幹細胞の合成と発見:ソルボサーマルアプローチ

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).

著者スポットライト:微多孔質材料化学における発見の加速 

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.

ハイスループット法を用いた等網状Al(III)ホスホネート系金属有機骨格化合物の発見と合成最適化

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