Bu çalışma JMBNRB verilir Doğa Bilimleri ve Kanada Ekipmanları, Discovery ve Discovery Hızlandırıcı Hibe Mühendislik Araştırma Konseyi tarafından desteklenen, Washington post-doktora burs programı Carnegie Institution destek kabul eder. Stephen Elardo ayrıca Jeofizik Lab&#39;de piston-silindir pres ile filme önce yaptığı yardım için teşekkür edilir.

Yazarlar ifşa hiçbir şey yok.

Burada özetlenen protokoller kullanılarak gerçekleştirilen içerme serbest deneylerin sonuçları, daha önce referans 29 (Os, Ir, Au), 30 (Re, Au) ve 31 (Pt) içinde literatür verileri ile karşılaştırılmıştır. Pt eklenmesi ücretsiz çalışma ürünlerin yararlılığını gösteren en öğreticidir. Düşük f O 2 çalıştırmak deneyler için, Ertel ve ark. 48 stabil bir kökeni kapanımlar atanan ve bu nedenle zamana bağımlı Y...

Karasal toplanma ay oluşumu 1,2 sorumlu düşündüm dev darbe aşamasında sonlanan bir chondritic toplu bileşimi ile gezegenciklere arasındaki çarpışmaların bir dizi olarak meydana geldiği düşünülmektedir. Darbelere tarafından proto-toprak ve kısa ömürlü izotopların çürüme ısıtma geniş erimesini ve magma okyanus veya Fe zengin metalik erir alçalma olabilir yoğun geçtiği göletlerin oluşmasına neden yeterli oldu. Magma okyanus tabanına ulaşarak üzerine, metalik erir bir reolojik sınır, durak karşılaşırsanız, ve sonunda büyüyen çekirdek 2 katı manto ile azalan önce son metal silikat denge tabi. Metalik eriyik olarak metal ve silikat fazlar arasındaki başka kimyasal haberleşme mantonun katı kısmı, büyüklüğü ve metal diyapirlerin 3 hızlı iniş engellemediği düşünülmektedir erişir. Metalik çekirdek ve silikat mant içine Dünya&#39;nın bu birincil farklılaşması6 - le hem jeofizik ve jeokimyasal gözlemler 4 bugün ortaya çıkar. Bir magma okyanus dibinde metal silikat denge için makul şartlar elde etmek için bu gözlemleri yorumlama Ancak, deney sonuçlarının uygun bir veritabanı gerektirir. İlkel üst manto (PUM) çekirdek oluşumunun silikat kalıntısı içeren bir varsayımsal rezervuar ve onun kompozisyonu bu nedenle metal silikat denge sırasında eser elementlerin davranışı yansıtmaktadır. İz elementler kendi jeokimyasal yakınlık temelinde çekirdek ayrımı esnasında metal ve silikat erir arasında dağıtılır. Metal faz için bir elemanlar tercih büyüklüğü metal silikat bölünme katsayısı ile tanımlanabilir <img alt="Denklem 1" src="/files/ftp_upload/52725/52725eq1.jpg" /><img alt="Denklem 2" src="/files/ftp_upload/52725/52725eq2.jpg" /> (1) Nerede <img alt="Denklem 3" src="/files/ftp_upload/52725/52725eq3.jpg" /> ve <img alt="Denklem 4" src="/files/ftp_upload/52725/52725eq4.jpg" /> Metal ve silikat, sırasıyla erime elemanının konsantrasyonunu ifade etmektedir. Değerleri <img alt="Denklem 5" src="/files/ftp_upload/52725/52725eq5.jpg" /> &gt; 1 siderophile (demir-seven) davranış ve bu &lt;1 litofil elementler (kaya seven) davranışı gösterir. Elemanları siderophile PUM kompozisyon gösterisi tahminleri genellikle Dünya&#39;nın toplu kompozisyon 6,8 temsilcisi olarak kabul Chondrites 7, göreli olarak tükenmiş. Bu tükenmesi çekirdek tarafından siderophile elemanlarının haciz nedeniyle ve refrakter elemanları kendi büyüklüğü doğrudan değerlerini yansıtmalıdır <img alt="Denklem 5" src="/files/ftp_upload/52725/52725eq5.jpg" /> . Laboratuvar deneyleri, bu nedenle değerlerini belirlemek için aramak <img alt="Denklem 5" src="/files/ftp_upload/52725/52725eq5.jpg" /> Bir ra üzerindebasınç (P), sıcaklık (T) ve oksijen fugasitesi (f O 2) magma okyanus tabanı metal ayrımı ile ilgili olan koşulların NGE. T - - Bu deneylerin sonuçları, o zaman P bölgelerini tanımlamak için kullanılabilir F O birden siderophile elemanlarının PUM bolluk ile uyumlu olan 2 alanı (örneğin, 9-11). yüksek basınç ve magma okyanus senaryoya uygun sıcaklıklar bir piston-silindir veya çok örs basın kullanılarak laboratuvarda yeniden olabilir. piston-silindir aparatı, orta basınç altında (~ 2 GPa) ve yüksek sıcaklık (~ 2573 K) koşulları erişim sağlar, ancak büyük örnek hacimleri ve kolay bir şekilde kullanılmak üzere, kapsül, çeşitli malzemeleri sağlar. hızlı bir soğutma hızı, aynı zamanda bu şekilde çalışma ürünlerin yapı yorumlanmasını kolaylaştırmak bir cam silikat eriyen bileşimlerin bir dizi su verme izin verir.Çok örs cihaz genellikle küçük örnek hacimleri istihdam ancak uygun montaj tasarımları ile baskıları için ~ 27 GPa ve ~ 3.000 K. sıcaklıkları bu yöntemlerin kullanılması orta çoğu için bölümleme verilerini izin ve hafif elementler olmak siderophile vardır elde edebilirsiniz T koşulları - P geniş bir ürün yelpazesi üzerinde toplandı. Bu verilere dayanarak, PVM bileşimin tahminler kesin değerler modele bağlı olmasına rağmen metal silikat denge, sırasıyla, ~ fazla ortalama basınç ve sıcaklık koşulları altında 29 GPa ve 3000 K meydana göstermektedir. (Örneğin, V, Cr,) 2, birlikte mevcut olan demir ve wüstite dayattığı aşağıda ~ 4-2 log birimi toplanmanın boyunca gelişmeye düşünülmektedir fO (bazı redoks duyarlı elemanların PUM bolluk FeO ortaya koymak üzere ) eşdeğeri PT koşullarında (demir-wüstite tampon) 12. Her ne kadar m PUM bolluğuHerhangi siderophile elemanları derin magma okyanus dibinde metal silikat denge ile açıklanabilir, bu durumun aynı zamanda en çok siderophile elemanlar (HSEs) için geçerli olup olmadığını değerlendirmek zor olduğu kanıtlanmıştır. Alçak basınç (P ~ 0.1 MPa) ve sıcaklık (T &lt;1,673 K) deneylerle gösterilen demir-metal için HSEs aşırı afinite silikat dünya kuvvetle bu unsurları tükenmiş olması gerektiğini göstermektedir. PUM HSE içeriğine tahminleri Bununla birlikte, (Şekil 1), kondrite yalnızca orta derecede bir tükenme göreli göstermektedir. Belirgin SEÇ aşırı Yaygın oturtulması çözüm Toprak çekirdek oluşumu 13 sonra chondritic malzemenin geç birikimini deneyimli olmasıdır. Bu geç • eklenir malzeme PUM ile karıştırılır ve SEÇ konsantrasyonları yükselmiş ancak daha bol unsurları üzerinde ihmal edilebilir bir etkiye sahip olurdu. Seçenek olarak ise, bu HSEs son derece siderophile doğası düşük basınç ile gösterilen ileri sürülmüştür </em&gt; - T deneyleri çekirdek oluşumu 14,15 sırasında mevcut yüksek YT şartlarına kalıcı değil. Bu hipotezi test etmek için, deneyler, uygun koşullarda HSEs çözünürlüğünün ve metal silikat ayırımını saptamak üzere gerçekleştirilmelidir. Ancak birçok önceki çalışmalarda söndürüldü çalışma ürünlerin silikat bölümünün kirlenmesi, çalışma ürün analizi komplike ve metal ve silikat ergiyiklerin arasındaki HSEs için de geçerlidir bölüm katsayıları gizlenmiş etti. HSEs doğasına uygun konsantrasyon düzeylerinde mevcut bölümleme deneylerde, Fe-metal, bu elemanların uç tercih silikat eriyik kendi ölçüm önler. Bu sorunu aşmak için, çözünürlük ölçümleri ilgi ve değerleri HSE hangi silikat eriyik doymuş çekilmiş <img alt="Denklem 5" src="/files/ftp_upload/52725/52725eq5.jpg" /> Borisov ve arkadaşları formalizmini kullanılarak hesaplanırark. 16. Indirgeyici koşullar gerçekleştirilmiştir SEÇ çözünürlük deneylerden Söndürülmüş silikat çalışma ürünleri, bununla birlikte, genellikle dağınık SEÇ ± Fe kirlenme kanıt görüntüler 17 inklüzyonlarını azaltır. Düşük f O bu kapanım yakın ubiquity rağmen Pt, Ir, Os, Re ve Ru içeren 2 deneyler (örneğin, 18-27), bunların dokusal sunum çalışmalar arasında önemli değişkenlik vardır; örnek 22 ve 26 başvuran için karşılaştırın. Bu inklüzyonlar bir deney 28 çalıştırma koşullarında stabil fazlı olan oluşturabilen olduğu gösterilmiş olmakla birlikte, Örnek söndürülür gibi bu inklüzyonların oluşumunu engellemez. Kapanım kökeni çevreleyen belirsizlik analitik sonuçların tedavisi zorlaştırır ve azaltılmış silikat erir içinde HSEs gerçek çözünürlüğü üzerinde belirsizliğe yol açtı. Kaynaştırma serbest çalışma ürünler değerlendirmek için gerekli olanhangi çalışmalar doğru çözünmüş HSE konsantrasyonlarını veren analitik bir yaklaşım benimsemiştir. 31 - indirgeyici koşullar metal-kapanım oluşumunu bastırmada kayda değer bir ilerleme şimdi örnek tasarım başlangıç ​​malzemeleri 29 Au veya Si ya da eklenmesi ile daha önceki çalışmalardan elde edilen tadil edilmiş olan bir piston-silindir düzeneği, kullanan deneylerde gösterilmiştir. Başlangıç ​​malzemelere Au veya element Si ilavesi sırasıyla deney numune geometrisi ya da f O 2 evrimi değiştirir. Bu yöntemler in difüzyon numune redüksiyon karşısında SEÇ zamanlamasının değiştirilmesiyle metal dahil oluşumunu bastırmak için tasarlanmıştır, ve Bennett ve ark., 31 tartışılmıştır. Böyle mekanik destekli dengeleme ve santrifüj piston-silindir olarak kapanım, silikat eriyiği temizlemek için önceki bazı girişimleri aksine, mevcut protokol uzman appar olmadan uygulanabilirATUS ve yüksek PT deneyler için de uygundur. Burada ayrıntılı olarak tarif edilen yüksek sıcaklıkta (&gt; 1873 K), 2 GPa ve benzer bir f, O 2 silikat eriyik Re, Os, ir, Ru, Pt ve Au çözünürlüğünü belirlemek için bir piston-silindir-tabanlı bir yaklaşımdır demir wüstite tamponu. Benzer bir deneysel tasarım uygulaması da, gerekli faz ilişkilerini sağlayan özelliklere ıslatma, diğer basınçta SEÇ deneylerinde başarılı ispat edebilir ve kinetik ilişkiler seçilen koşullara devam etmektedir. Ancak mevcut veriler, bizim örnek tasarımı derin magma okyanus gelen baskılara başarılı olup olmayacağını tahmin etmek yeterli değildir. Ayrıca özetlenen orta ve hafif siderophile elemanı (MSE ve SSE sırasıyla) çok örs cihaz kullanarak bölümleme belirlemek için kullanılan genel bir yaklaşımdır. Yüksek basınç HSEs için eklenmesi ücretsiz veri kümesi Uzatma benzer multi-örs yöntemleri kullanılması muhtemeldir. Giysieter, bu prosedürler çekirdek ayrışma koşulları ve karasal accretion aşamaları hem sınırlamak için bir araç sağlar.

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			<td>G10 Epoxy/Fiberglass Sheet</td>
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			<td>Powdered starting materials- -Oxides, metals, carbonates</td>
			<td>Alfa Aesar</td>
			<td>Specific to desired experiment</td>
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			<td>Castable 2-part MgO ceramic</td>
			<td>Aremco</td>
			<td>Ceramcast - 584</td>
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			<td>Concept Alloys</td>
			<td>N/A</td>
			<td>~0.25 mm diameter is suitable for most experiments</td>
		</tr>
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			<td>Zirconia Cement</td>
			<td>Cotronics; Resbond 940 2-part cement</td>
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			<td>e.g Krazy Glue/Loctite</td>
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			<td>4-hole alumina tube for multi-anvil thermocouple</td>
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</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.

silikat düşük f O 2 erir deneyler aşağıdaki örnekler ve tartışma odağı SEÇ çözünürlüğünü belirlemek için. T - - Çok örs deneylerden elde MSE ve SSE bölümleme veri P sınırlamak için nasıl kullanılabileceğini kapsamlı örnekler için f O çekirdek metal ayrıştırma 2 koşulları, okuyucu başvuruları 9 anılır -. 11 Şekil 7B-D geri görüntüler Tipik deneysel çalışma ürünlerden dağı...

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.

Deneysel Yöntemlerle ve yüksek Siderophile Eleman kapsama alınan terimler bastır için Protokolün: Yüksek Basınç ve Sıcaklık metal-silikat bölümleme

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

metal-silicate-partitioning-at-high-pressure-temperature-experimental

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12.4K Görüntüleme.  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.

Video: 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.

CO Faz Dengeleri Ölçümleri için yüksek basınçlı Safir Hücre<sub&gt; 2</sub&gt; / / Organik Su Sistemleri

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

Kimya

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.

Paralel Basınç Reaktörleri ve Zincir Transferi Polimerizasyon bir Kinetik Analizi Etilen Polimerizasyonlar

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.

Oda sıcaklığında karbon Nanosheets hazırlanması

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.

Sentezi İçin Protokol<em&gt; Ortho</em&gt; -trifluoromethoxylated Anilin türevleri

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.

Gerçek Zamanlı Yüksek Çözünürlüklü Kütle Spektrometresi Doğrudan Analizi Kullanılarak Botanik Malzeme Hızlı Yüksek verim Türler Kimlik

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.

Yüksek Basınçlı PX de Tek Kristal Kırınımı ^ 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.

Verimli Yüksek Sıcaklık Kimyası İçin Denge Dışı Mikrodalga Plazma

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.

Yüksek basınçlı Sıvı Kromatografi ile Glukosinolat Ekstraksiyon ve Analiz A Basit Yöntemi (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.

Ayıklama ve çözümleme katekoiamin nörotransmitter ve onların metabolitleri yüksek basınçlı sıvı Kromatografi ile uygun bir yöntem

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.

Mikroyerçekimi Ortamında Verimli Güneş HidrojenI Üretimi Için Deneysel Yöntemler

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