وأيد هذا العمل من قبل العلوم الطبيعية والهندسة مجلس البحوث كندا المعدات، ديسكفري وديسكفري مسرع المنح المقدمة للJMBNRB يعترف بدعم من مؤسسة كارنيجي في برنامج زمالة ما بعد الدكتوراه واشنطن. وشكر ستيفن Elardo أيضا لمساعدته قبل التصوير مع الصحافة مكبس الاسطوانة في مختبر للفيزياء الأرضية.

المؤلفين ليس لديهم ما يكشف.

وقد سبق مقارنة نتائج التجارب الحرة إدراج تنفيذها باستخدام البروتوكولات المذكورة هنا مع بيانات الأدب في المراجع 29 (OS، عير، والاتحاد الافريقي)، 30 (إعادة والاتحاد الافريقي) و 31 (حزب العمال). حزب العمال هو الأكثر المفيد في إثبات جدوى المنتجات المدى خالي?...

ويعتقد أن تراكم الأرضية وقعت على شكل سلسلة من التصادمات بين الكويكبات مع تكوين الجزء الأكبر chondritic، تنتهي في مرحلة تأثير العملاقة يعتقد أنها المسؤولة عن تكوين القمر 1،2. وكانت التدفئة من بروتو الأرض عن طريق الآثار واضمحلال النظائر قصيرة الأجل كافية للتسبب ذوبان واسع وتشكيل محيط الصهارة أو البرك التي من خلالها كثيفة يذوب المعدنية الحديد الغنية يمكن أن تنزل. عند الوصول إلى قاعدة محيط الصهارة، يذوب المعدنية تصادف الانسيابية الحدود، المماطلة، وتخضع النهائي توازن المعادن سيليكات قبل تنازلي نهاية المطاف من خلال عباءة صلبة حتى النخاع المتزايد 2. الاتصالات الكيميائية مزيد من بين المعدن ومراحل السيليكات كما تذوب معدنية تقطع يعتقد أن الجزء الصلب من عباءة أن يمنع ذلك بسبب الحجم الكبير والنسب السريع لdiapirs المعادن 3. هذا التمايز الأساسي من الأرض إلى نواة معدنية وMANT سيليكاتوكشفت جنيه اليوم الملاحظات الجيوفيزيائية والجيوكيميائية كلا 4-6. تفسير هذه الملاحظات أن تحقق شروط معقولة للتوازن المعادن سيليكات في قاعدة محيط الصهارة، ومع ذلك، يتطلب وجود قاعدة بيانات مناسبة من النتائج التجريبية. عباءة العليا البدائية (PUM) هي خزان افتراضية تتألف من بقايا السيليكات من تشكيل الأساسي، وبالتالي يعكس تكوينه سلوك العناصر النزرة خلال توازن المعادن سيليكات. يتم توزيع العناصر النزرة بين المعدن وسيليكات يذوب خلال فصل الأساسية على أساس قرابتهم الجيوكيميائية. حجم تفضيل العناصر للمرحلة معدن يمكن وصفها من قبل معامل تفريق معدن سيليكات <img alt="المعادلة 1" src="/files/ftp_upload/52725/52725eq1.jpg" /><img alt="المعادلة 2" src="/files/ftp_upload/52725/52725eq2.jpg" /> (1) أين <img alt="المعادلة 3" src="/files/ftp_upload/52725/52725eq3.jpg" /> و <img alt="المعادلة 4" src="/files/ftp_upload/52725/52725eq4.jpg" /> دلالة على تركيز العنصر الأول في المعادن وسيليكات تذوب على التوالي. قيم <img alt="المعادلة 5" src="/files/ftp_upload/52725/52725eq5.jpg" /> &gt; 1 تشير siderophile السلوك (المحبة الحديد) وهذه &lt;1 lithophile (المحبة الصخور) السلوك. تنضب تقديرات المعرض تكوين PUM أن siderophile عناصر نسبة إلى chondrites 7، والذي يعتبر عادة ممثلا من تكوين الأرض السائبة 6،8. ومن المقرر أن عزل العناصر siderophile التي كتبها جوهر هذا الاستنزاف، وعناصر صهر حجمها ينبغي أن تعكس قيم مباشرة <img alt="المعادلة 5" src="/files/ftp_upload/52725/52725eq5.jpg" /> . لذا تسعى التجارب المعملية لتحديد قيم <img alt="المعادلة 5" src="/files/ftp_upload/52725/52725eq5.jpg" /> أكثر من رانجى من الضغط (P)، ودرجة الحرارة (T) وسرعة الزوال الأكسجين (و O 2) الشروط التي لها صلة العزل المعادن من قاعدة محيط الصهارة. ومن ثم يمكن استخدام نتائج هذه التجارب لتحديد مناطق P - T - و O 2 المساحة التي تتوافق مع وفرة PUM من عناصر siderophile متعددة (على سبيل المثال، 9-11). الضغوط العالية ودرجات الحرارة ذات الصلة لسيناريو محيط الصهارة يمكن صوغه في المختبر باستخدام مكبس اسطوانة أو اضغط متعدد سندان. يوفر جهاز مكبس الاسطوانة الوصول إلى ضغط معتدل (~ 2 جيد جدا) ودرجة حرارة عالية (~ 2573 K) الظروف، ولكن يمكن أحجام عينة كبيرة ومتنوعة من المواد كبسولة ليتم استخدامها بسهولة. يسمح معدل التبريد السريع أيضا تبريد مجموعة من المؤلفات ذوبان سيليكات إلى الزجاج، وبالتالي تبسيط تفسير التكوينية للمنتجات التشغيل.جهاز متعدد سندان عادة توظف أحجام عينات صغيرة ولكن مع تصاميم التجمع مناسبة يمكن تحقيق ضغوط تصل إلى ~ 27 جيغا ودرجات الحرارة ~ 3000 K. استخدام هذه الأساليب قد سمح البيانات التقسيم للعديد من متوسطة وطفيفة siderophile العناصر لتكون تجمع أكثر من مجموعة واسعة من P - شروط T. وتشير التوقعات لتكوين PUM بناء على هذه البيانات حدث توازن المعادن سيليكات بمتوسط ​​ظروف الضغط والحرارة التي تتجاوز 29 ~ برنامج العمل العالمي وK 3000 على التوالي، على الرغم من أن القيم هي بالضبط نموذج التابعة. من أجل تفسير وفرة PUM من العناصر الحساسة الأكسدة معينة (على سبيل المثال، V، CR) و في O 2 ويعتقد أيضا أن تتطور خلال تراكم من ~ 4-2 وحدات سجل أقل من ذلك الذي تفرضه الحديد تتعايش وwüstite (فيو ) في ظروف PT أي ما يعادل (المخزن المؤقت الحديد wüstite) 12. على الرغم من وفرة PUM من ميمكن أن يعزى أي عناصر siderophile عليها توازن المعادن سيليكات في القاعدة من الصهارة أعماق المحيطات، فقد ثبت أنه من الصعب تقييم ما إذا كان ينطبق هذا الوضع أيضا إلى أكثر siderophile غاية العناصر (HSEs). تقارب الشديد في HSEs للحديد والمعادن المشار إليها بواسطة الضغط المنخفض (P ~ 0.1 ميجا باسكال) ودرجة الحرارة (T &lt;1673 K) التجارب تشير إلى أن تستنفد بقوة الأرض سيليكات في هذه العناصر. تقديرات محتوى HSE لPUM، ومع ذلك، تشير فقط استنزاف قريب معتدلة إلى كوندريت (الشكل 1). حل افترض عادة إلى فائض الصحة والسلامة واضحا هو أن الأرض شهدت أواخر تراكم من المواد chondritic اللاحقة لتشكيل النواة 13. ان هذه المواد في وقت متأخر من يتراكم ومختلطة مع PUM ورفع تركيزات HSE ولكن كان له تأثير يذكر على عناصر أكثر وفرة. بدلا من ذلك، فقد قيل أن طبيعة siderophile للغاية من HSEs أشارت بانخفاض P </em&gt; - تجارب T لا تزال قائمة للشروط PT الحالية المرتفعة خلال النوى تشكيل 14،15. من أجل اختبار هذه الفرضيات، يجب أن تتم التجارب لتحديد ذوبان والمعادن سيليكات تقسيم HSEs في الظروف المناسبة. تلوث الجزء سيليكات منتجات التشغيل مروي في العديد من الدراسات السابقة ومع ذلك، فقد تعقدت تحليل التشغيل المنتج وتحجب معاملات التقسيم الحقيقية لHSEs بين المعدن ويذوب السيليكات. في تجارب التقسيم حيث هي موجودة في مستويات التركيز المناسبة لطبيعة HSEs، وتفضيل الشديد من هذه العناصر للالحديد معدن يمنع قياسها في ذوبان سيليكات. للتحايل على هذه المشكلة، يتم إجراء قياسات الذوبان التي تشبع ذوبان سيليكات في HSE المصالح والقيم <img alt="المعادلة 5" src="/files/ftp_upload/52725/52725eq5.jpg" /> يتم حسابها باستخدام الشكلية من بوريسوف وآخرونآل 16. سيليكات مروي المنتجات التشغيل من HSE التجارب الذوبان أجريت في الحد من الظروف، ولكن في كثير من الأحيان عرض الأدلة على التلوث فرقت HSE ± الحديد الادراج 17. على الرغم من كل مكان القريب من هذه الادراج في منخفض و O 2 التجارب التي تحتوي على حزب العمال، عير، ونظام التشغيل، وإعادة رو، (على سبيل المثال، 18-27)، هناك تفاوتا ملحوظا بين الدراسات في عرضها التكوينية. مقارنة على سبيل المثال يحيل الى 22 و 26. وإن كان قد ثبت أن شوائب يمكن أن تشكل والتي هي مرحلة مستقرة في المدى شروط تجربة 28، وهذا لا يمنع تشكيل الادراج كما هو مروي العينة. الغموض الذي يلف أصل الادراج يجعل العلاج من النتائج التحليلية صعبة، وأدى إلى غموض على الذوبان الحقيقي للHSEs في خفض سيليكات يذوب. مطلوبة منتجات المدى خالية من إدراج لتقييموقد اعتمد التي دراسات نهج تحليلي يمكن أن ينتج تركيزات HSE المنحل دقيقة. وقد تم الآن أظهرت تقدما كبيرا في قمع تشكيل المعادن الادراج في ظروف الحد في التجارب باستخدام جهاز مكبس الاسطوانة، التي تم تعديل تصميم عينة من الدراسات السابقة عن طريق إما الاتحاد الافريقي أو سي إلى المواد الأولية 29-31. إضافة الاتحاد الافريقي أو عنصري سي إلى المواد الأولية يغير تطور عينة الهندسة أو و O 2 التجربة على التوالي. وتهدف هذه الأساليب لقمع تشكيل إدراج المعدن عن طريق تغيير توقيت HSE في نشر مقابل الحد من العينة، ويتم مناقشتها في بينيت وآخرون. 31. وخلافا لبعض المحاولات السابقة لتطهير ذوبان سيليكات من شوائب، مثل موازنة بمساعدة ميكانيكيا والطرد المركزي مكبس الاسطوانة، لا يمكن تنفيذ هذا البروتوكول دون appar المتخصصةatus وغير مناسبة لإجراء التجارب PT عالية. وصفت بالتفصيل هنا هو النهج القائم على مكبس الاسطوانة لتحديد ذوبان رد، ونظام التشغيل، عير، رو، وحزب العمال والاتحاد الافريقي في ذوبان سيليكات في درجة حرارة عالية (&gt; 1873 K)، 2 جيغا وو لO 2 مماثلة لتلك التي المخزن المؤقت الحديد wüstite. تطبيق التصميم التجريبي مماثل قد يكون ناجحا أيضا في تجارب HSE في الضغوط الأخرى، وتوفير العلاقات المرحلة المطلوبة، ترطيب خصائص وتستمر العلاقات الحركية للشروط المختار. ومع ذلك البيانات الموجودة، غير كافية لتوقع ما إذا كان تصميم عينة لدينا وسوف يكون ناجحا في الضغوط المقابلة لالصهارة أعماق المحيطات. أوجز أيضا هو نهج عام يستخدم لتحديد عنصر siderophile متوسطة وطفيفة (MSE وSSE على التوالي) التقسيم باستخدام جهاز متعدد سندان. تمديد بيانات خالية من إدراج لHSEs إلى ارتفاع ضغط ومن المرجح أن استخدام وسائل متعددة سندان-مماثلة. أكسيالأثير، وتوفر هذه الإجراءات وسيلة لتقييد كل الشروط من النوى العزل ومراحل التنامي الأرضية.

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	<tbody>
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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>
			<td></td>
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			<td>Castable 2-part MgO ceramic</td>
			<td>Aremco</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>
		<tr>
			<td>Zirconia Cement</td>
			<td>Cotronics; Resbond 940 2-part cement</td>
			<td>N/A</td>
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			<td>e.g Bostik</td>
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			<td>Often sold as &#39;white glue&#39;</td>
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			<td>e.g Krazy Glue/Loctite</td>
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			<td>Piston cylinder pressure vessel and WC piston</td>
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			<td>Single hole alumina tube for multi-anvil thermocouple</td>
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			<td>4-hole alumina tube for piston cylinder thermocouple</td>
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			<td>AXF1159--07-12&#160;</td>
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			<td>4-hole alumina tube for multi-anvil thermocouple</td>
			<td>Vesuvius McDanel</td>
			<td>AXF1159-04-06</td>
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	</tbody>
</table>

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

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

الأمثلة التالية والتركيز على مناقشة التجارب لتحديد HSE الذوبان في سيليكات يذوب في f منخفضة O 2. للحصول على أمثلة شاملة عن كيفية يمكن استخدام MSE والبيانات تقسيم SSE من تجارب متعددة السندان لتقييد P - T - و O 2 ظروف المعادن الأساسية العزل، وعلى ال...

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.

تقسيم المعادن سيليكات في ارتفاع الضغط ودرجة الحرارة: الطرق التجريبية وبروتوكول قمع بشدة Siderophile العنصر الادراج

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

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12.4K Views.  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.

ارتفاع ضغط سيل الياقوت للمرحلة التوازنات قياسات CO<sub&gt; 2</sub&gt; / العضوية / أنظمة المياه

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

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.

Polymerizations الإثيلين عن طريق المفاعلات الضغط الموازية وتحليل الحركية من سلسلة البلمرة نقل

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.

إعداد Nanosheets الكربون في درجة حرارة الغرفة

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.

بروتوكول لتوليف<em&gt; أورثو</em&gt; مشتقات الانيلين -trifluoromethoxylated

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.

سريع سرعة عالية الإنتاجية الأنواع النباتية تحديد المواد عن طريق تحليل المباشر في الوقت الحقيقي عالية الدقة قياس الطيف الكتلي

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.

ارتفاع الضغط واحد كريستال حيود في مقصف ^ 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.

عدم التوازن الميكروويف الميكروويف للكفاءة عالية درجة الحرارة الكيمياء

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.

ومن الطرق المباشرة لGlucosinolate استخراج وتحليل مع الضغط العالي اللوني السائل (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.

طريقة مريحة لاستخراج وتحليل مع اللوني السائل عالي الضغط الكاتيكولامينات العصبية وعلى نواتج الأيض

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.

الأساليب التجريبية لإنتاج الهيدروجين الفعال بالطاقة الشمسية في بيئة الجاذبية الصغريه

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