这项工作得到了作者 YL 的启动基金和加州州立大学萨克拉门托分校的教学法增强奖 （PEA） 的支持。

1、油源及制备
<ol><li>将 2.0 mL HPLC 级甲醇加入 15 mL 离心管中。 注意:甲醇是一种高度易燃的液体。吞咽、与皮肤接触或吸入有毒，会对眼睛造成伤害。确保在使用甲醇时穿戴个人防护设备 （PPE），并在通风橱中使用。</li>
	<li>向离心管中加入一粒 KOH （~0.10 g），并使用超声波清洁器 （40 kHz） 溶解 KOH 固体，只需打开超声波。 注意:吞咽 KOH 是有害的。它会导致严重的皮肤灼伤、眼睛损伤和严重的眼睛损伤。确保在使用这种物质时穿戴个人防护装备。 注意: 为获得最佳结果，请将离心管放入装满水的烧杯中，然后将烧杯放入超声波浴中。这种浸没式配置保证了反应混合物彻底暴露在超声波照射下，从而最大限度地提高其有效性。</li>
</ol>2. 酯交换工艺
<ol><li>将 8.0 mL 特级初榨橄榄油加入离心管中。</li>
	<li>盖上离心管盖子并盖紧，用力摇晃离心管，使油和甲醇钾溶液混合。 注意: 摇晃离心管时，请保持离心机盖紧。</li>
	<li>松开盖子，将离心管放入超声波浴中。打开超声波浴1分钟。</li>
	<li>第一个 1 分钟后，拧紧离心机盖，再次剧烈摇晃离心管。</li>
	<li>松开盖子，将反应混合物放入超声波浴中再放置14分钟。</li>
	<li>将反应混合物转移到分液漏斗中，并排空底部甘油层。</li>
	<li>用 15 mL 饱和 NaCl 溶液洗涤顶层 3 次，以洗去酯中多余的甲醇和残留的催化剂。用 pH 试纸测试，确保最终洗涤的 pH 值为中性。</li>
	<li>将顶部生物柴油层转移到干燥、干净的小瓶中，向小瓶中加入无水 Na2SO4，涡旋混合物，让混合物静置约 15 分钟，直到生物柴油澄清。使用透明生物柴油产品进行表征。</li>
</ol>3. 生物柴油的表征
<ol><li>傅里叶变换红外 （FT-IR） 分析<ol><li>记录 FT-IR 光谱，范围为 4000-400 cm-1。通过以 4 cm-1 的分辨率共加 16 个扫描来测量每个样品。通过在每次样品扫描前采集新鲜空气光谱来执行背景减法。这是为了确保准确的基线校正和最小的样品污染。在每个新样品之前，使用甲醇清洁 ATR 板，然后用无绒湿巾擦干。</li>
	</ol></li>
	<li>质子核磁共振 （1H NMR） 分析<ol><li>要分析生物柴油产品的化学成分，请在室温下在 500 MHz NMR 波谱仪上记录生物柴油和特级初榨橄榄油的核磁共振 （NMR） 波谱。利用高分辨率 5 mm 双梯度探针，通过将 50 mg 样品溶解在含有 0.05% 四甲基硅烷 （TMS） 的 0.7 mL 氘代氯仿 （CDCl3） 中作为内标来制备每个样品。使用 TOPSPIN 程序采集 1H NMR 谱图，进行 16 次扫描，并以 0.0 ppm 的 TMS 标准为参考。 注意:CDCl3 如果吞咽是有害的，如果吸入是有毒的。它会引起皮肤刺激和严重的眼睛刺激。使用这种物质时，请穿戴个人防护装备。</li>
	</ol></li>
	<li>粘度分析<ol><li>准备两个 5.75 英寸玻璃巴斯德移液器和一个移液器泵。</li>
		<li>用笔在每个移液器上做两个标记。顶部标记在移液器主体上，第二个标记位于窄柄上，距尖端约 2 厘米。</li>
		<li>使用移液器泵将特级初榨橄榄油填充到移液器中，弯月面位于顶部标记处。</li>
		<li>取下移液器泵并启动秒表。当特级初榨橄榄油达到较低标记时停止秒表。</li>
		<li>重复步骤3.3.3和3.3.4，使用生物柴油产品而不是特级初榨橄榄油。</li>
		<li>通过定时通过玻璃移液管来确定生物柴油与特级初榨橄榄油的相对粘度。 相对粘度=（油时间）/（生物柴油时间）。</li>
	</ol></li>
	<li>可燃性测试<ol><li>将一根长约 2 厘米的棉绳浸入生物柴油中，将另一根棉绳浸入特级初榨橄榄油中。确保管柱与相应的液体完全饱和。将涂有涂层的棉绳放在铝箔上。</li>
		<li>在指定的实验室区域，远离易燃溶剂，评估点燃每根棉线的难易程度，并观察产生的火焰的质量。确定一根棉绳是否比另一根棉绳更容易点燃。评估哪种液体具有卓越的芯吸能力，哪种液体能保持更强的燃烧。</li>
	</ol></li>
</ol>

通过超声辅助植物油酯交换合成生物柴油

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作者没有什么可透露的。

在该演示中，阐明了一种超声波辅助方法，用于碱催化生产生物柴油，以实现最佳功效。为获得最佳结果，应将离心管放入装满水的烧杯内，然后将烧杯放入超声波浴中。这种浸没式配置保证了反应混合物彻底暴露于超声波处理中，从而最大限度地提高其有效性。如果需要，也可以使用离心架来替换超声波浴内的烧杯，这可以进一步降低超声波的噪音。
正确的溶剂选择是通?...

生物柴油源自常见的植物性油脂，是一种减轻对石油依赖的可持续解决方案1。这种可再生替代品展示了减少温室气体排放，特别是二氧化碳，同时依赖于可持续资源。此外，与石油柴油相比，生物柴油具有明显的优势，其特点是不含硫成分、无毒和可生物降解性。作为传统化石燃料的替代品，生物柴油通过减少我们对不可再生化石燃料的依赖并减轻气候变化的不利影响，符合联合国 （UN） 的净零政策。生物柴油为满足当前的能源需求提供了一条充满希望的途径，使其成为更绿色未来的有力选择2.
用于生物柴油生产的主要方法涉及酯交换反应，这是一种化学过程，其中油脂中的甘油三酯在高温条件下在催化剂存在下与醇（通常是甲醇或乙醇）发生反应1,2,3,4。该反应产生脂肪酸烷基酯，这是生物柴油的主要成分。各种类型的植物油是生物柴油生产的主要原料，包括食用油5（例如，特级初榨橄榄油和玉米油）和非食用油 6,7,8（例如，刺山柑籽油），以及废油9。甲醇最常用于这种酯交换过程，因为它是一种相对便宜的醇。此外，一系列催化剂（如硫酸、磷酸、氢氧化钾、氢氧化钠）或酶（如脂肪酶）可用于加速酯交换过程1,2,3,4。传统上，反应混合物在回流下长时间加热，通常为 30 分钟或更长时间。加热不如超声波加热节能，同时也存在安全风险5.因此，需要一种更安全、更快、更节能的酯交换工艺。
超声波辐照是热、光和电等传统能源的优质替代品，这主要是由于声空化现象10。这种现象的特征是气泡的形成、膨胀和剧烈崩溃，产生温度达到约 5000 K、压力为 1000 个大气压的局部热点。这种极端条件，加上快速的加热和冷却速率（超过 1010 K/s），为在室温下有效发生各种化学反应提供了必要的能量，包括那些以前认为通过传统方法无法达到的反应10。超声波辅助合成在各个研究领域迅速普及。值得注意的是，人们对有机合成和固态材料中的超声波辅助合成的兴趣是由其环保性质、能源效率和环境条件下缩短的反应时间推动的 5,11,12,13,14,15,16 .本文介绍了一种快速有效的技术，用于使用碱性催化剂对植物油进行安全的超声辅助酯交换反应，从而在短时间内产生纯生物柴油产品。虽然特级初榨橄榄油是本研究中的演示培养基，但必须注意的是，超声波方法适用于一系列植物油5,17。

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Chloroform-d</td>
			<td>Fisher Scientific</td>
			<td>865-49-6</td>
			<td>&#8226; Harmful if swallowed. 
			&#8226; Causes skin irritation. 
			&#8226; Causes serious eye irritation. 
			&#8226; Toxic if inhaled. 
			&#8226; Suspected of causing cancer. 
			&#8226; Suspected of damaging fertility or the unborn child. 
			&#8226; Causes damage to organs through prolonged or repeated exposure</td>
		</tr>
		<tr>
			<td>Heated Ultrasonic Baths, Digital, Branson Ultrasonic</td>
			<td>Branson&#160;</td>
			<td>89375-492</td>
			<td></td>
		</tr>
		<tr>
			<td>Methanol</td>
			<td>Fisher Scientific Company</td>
			<td>67-56-1</td>
			<td>Highly flammable liquid and vapor. Toxic if swallowed, in contact with skin or if inhaled. Causes damage to organs (Eyes).</td>
		</tr>
		<tr>
			<td>Potassium hydroxide&#160;</td>
			<td>Fisher Scientific Company</td>
			<td>1310-58-3</td>
			<td>May be corrosive to metals. Harmful if swallowed. Causes severe skin burns and eye damage. Causes serious eye damage</td>
		</tr>
		<tr>
			<td>Sodium chloride</td>
			<td>Sigma-Aldrich</td>
			<td>7647-14-5</td>
			<td>Not hazardous</td>
		</tr>
		<tr>
			<td>Vegetable oils</td>
			<td></td>
			<td></td>
			<td>A commonly consumed food with a long history of safe use in pesticides.&#160;</td>
		</tr>
	</tbody>
</table>

ultrasonic-assisted preparation of biodiesel products from vegetable oils

本研究利用植物油作为可持续的原料，提出了一种用于生物柴油合成的超声波辅助酯交换的创新方法。这种碱性催化的程序利用超声波作为有效的能量输入，促进了特级初榨橄榄油快速转化为生物柴油。在本演示中，反应在环境条件下的超声波浴中运行15分钟，需要1:6的特级初榨橄榄油与甲醇的摩尔比和最少量的KOH作为催化剂。还报道了生物柴油的理化性质。该方法强调了超声波辅助酯交换的显著优势，可显著减少反应和分离时间，实现近乎完美的纯度 （~100%）、高产量和可忽略不计的废物产生。重要的是，这些好处是在优先考虑安全和环境可持续性的框架内实现的。这些令人信服的发现强调了这种方法在将植物油转化为生物柴油方面的有效性，使其成为研究和实际应用的可行选择。

在此演示中，由 KOH 催化的特级初榨橄榄油和甲醇的酯交换反应在室温下在超声波浴中生产生物柴油（图 1）5。离心管中的起始材料显示反应物是不混溶的，并分为两层，如图 2A 所示。上层是甲醇和KOH的混合物，而下层则由特级初榨橄榄油组成。为了促进均质化，建议在对离心管进行超声搅拌之前对反应物进行短暂的预混合。
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Read this Scientific Article Protocol about Author Spotlight: Employing Green-Chemistry Principles for Safe and Sustainable Synthesis of Biodiesels at JoVE.com

作者聚焦:采用绿色化学原则安全可持续地合成生物柴油

本文介绍了一种使用碱性催化剂对植物油进行安全的超声辅助酯交换方法。该方法对于制备纯生物柴油产品具有快速有效的效果。

超声辅助制备植物油生物柴油产品

Utilizing vegetable oil as a sustainable feedstock, this study presents an innovative approach to ultrasonic-assisted transesterification for biodiesel ...

我们的研究引入了一种环保且安全的方法，通过超声波辅助酯交换反应生产生物柴油。我们正试图回答如何运用绿色化学原理并利用超声波能量来促进反应。我们目前正在使用超声波技术来增强反应的可持续性，遵循绿色化学的原则。我们开发了一种安全、快速和高效的方法，用于从植物油合成高纯度生物柴油。该方法在常温和常压下合成生物柴油，比传统的加热方式更节能、更安全。此外，生物柴油产品的纯度接近100%

ultrasonic-assisted-preparation-biodiesel-products-from-vegetable

Research

JoVE Journal

Chemistry

Ultrasonic-Assisted Preparation of Biodiesel Products from Vegetable Oils

879 次观看.  California State University, Sacramento. 我们的研究引入了一种环保且安全的方法，通过超声波辅助酯交换反应生产生物柴油。我们正试图回答如何运用绿色化学原理并利用超声波能量来促进反应。我们目前正在使用超声波技术来增强反应的可持续性，遵循绿色化学的原则。我们开发了一种安全、快速和高效的方法，用于从植物油合成高纯度生物柴油。该方法在常温和常压下合成生物柴油，比传统的加热方式?...

视频: 作者聚焦:采用绿色化学原则安全可持续地合成生物柴油

A Direct, Early Stage Guanidinylation Protocol for the Synthesis of Complex Aminoguanidine-containing Natural Products

The guanidine functional group, displayed most prominently in the amino acid arginine, one of the fundamental building blocks of life, is an important structural element found in many complex natural products and pharmaceuticals. Owing to the continual discovery of new guanidine-containing natural products and designed small molecules, rapid and efficient guanidinylation methods are of keen interest to synthetic and medicinal organic chemists. Because the nucleophilicity and basicity of guanidines can affect subsequent chemical transformations, traditional, indirect guanidinylation is typically pursued. Indirect methods commonly employ multiple protection steps involving a latent amine precursor, such as an azide, phthalimide, or carbamate. By circumventing these circuitous methods and employing a direct guanidinylation reaction early in the synthetic sequence, it was possible to forge the linear terminal guanidine containing backbone of clavatadine A to realize a short and streamlined synthesis of this potent factor XIa inhibitor. In practice, guanidine hydrochloride is elaborated with a carefully constructed protecting array that is optimized to survive the synthetic steps to come. In the preparation of clavatadine A, direct guanidinylation of a commercially available diamine eliminated two unnecessary steps from its synthesis. Coupled with the wide variety of known guanidine protecting groups, direct guanidinylation evinces a succinct and efficient practicality inherent to methods that find a home in a synthetic chemist&#39;s toolbox.

Here, we present a protocol for direct, early stage guanidinylation that enables rapid total synthesis of aminoguanidine-containing small organic molecules. An advanced synthetic intermediate used in the synthesis of a blood coagulation factor XIa inhibitor was prepared using this protocol.

一个直接的，早期胍基协议的复杂含氨基胍，天然产物合成

The guanidine functional group, displayed most prominently in the amino acid arginine, one of the fundamental building blocks of life, is an important ...

科研

化学

X-ray Powder Diffraction in Conservation Science: Towards Routine Crystal Structure Determination of Corrosion Products on Heritage Art Objects

The crystal structure determination and refinement process of corrosion products on historic art objects using laboratory high-resolution X-ray powder diffraction (XRPD) is presented in detail via two case studies.
The first material under investigation was sodium copper formate hydroxide oxide hydrate, Cu4Na4O(HCOO)8(OH)2&#8729;4H2O (sample 1) which forms on soda glass/copper alloy composite historic objects (e.g., enamels) in museum collections, exposed to formaldehyde and formic acid emitted from wooden storage cabinets, adhesives, etc. This degradation phenomenon has recently been characterized as &#34;glass induced metal corrosion&#34;.
For the second case study, thecotrichite, Ca3(CH3COO)3Cl(NO3)2&#8729;6H2O (sample 2), was chosen, which is an efflorescent salt forming needlelike crystallites on tiles and limestone objects which are stored in wooden cabinets and display cases. In this case, the wood acts as source for acetic acid which reacts with soluble chloride and nitrate salts from the artifact or its environment.
The knowledge of the geometrical structure helps conservation science to better understand production and decay reactions and to allow for full quantitative analysis in the frequent case of mixtures.

Modern high resolution X-ray powder diffraction (XRPD) in the laboratory is used as an efficient tool to determine crystal structures of long-known corrosion products on historic objects.

X射线粉末衍射在保护科学:迈向文物艺术品腐蚀产物的常规晶体结构测定

The crystal structure determination and refinement process of corrosion products on historic art objects using laboratory high-resolution X-ray powder ...

Preparation of Biopolymer Aerogels Using Green Solvents

Although the first reports on aerogels made by Kistler1 in the 1930s dealt with aerogels from both inorganic oxides (silica and others) and biopolymers (gelatin, agar, cellulose), only recently have biomasses been recognized as an abundant source of chemically diverse macromolecules for functional aerogel materials. Biopolymer aerogels (pectin, alginate, chitosan, cellulose, etc.) exhibit both specific inheritable functions of starting biopolymers and distinctive features of aerogels (80-99% porosity and specific surface up to 800 m2/g). This synergy of properties makes biopolymer aerogels promising candidates for a wide gamut of applications such as thermal insulation, tissue engineering and regenerative medicine, drug delivery systems, functional foods, catalysts, adsorbents and sensors. This work demonstrates the use of pressurized carbon dioxide (5 MPa) for the ionic cross linking of amidated pectin into hydrogels. Initially a biopolymer/salt dispersion is prepared in water. Under pressurized CO2 conditions, the pH of the biopolymer solution is lowered to 3 which releases the crosslinking cations from the salt to bind with the biopolymer yielding hydrogels. Solvent exchange to ethanol and further supercritical CO2 drying (10 - 12 MPa) yield aerogels. Obtained aerogels are ultra-porous with low density (as low as 0.02 g/cm3), high specific surface area (350 - 500 m2/g) and pore volume (3 - 7 cm3/g for pore sizes less than 150 nm).

A new way for the production of biopolymer-based aerogels by carbon dioxide (CO2) induced gelation is shown. The technique utilizes pressurized carbon dioxide (5 MPa) for the production of biopolymer hydrogels and supercritical CO2 (12 MPa) to convert gels into aerogels. The only solvents needed besides CO2 are water and ethanol.

生物聚合物气凝胶制备使用绿色溶剂

Although the first reports on aerogels made by Kistler1 in the 1930s dealt with aerogels from both inorganic oxides (silica and others) and biopolymers ...

Green and Low-cost Production of Thermally Stable and Carboxylated Cellulose Nanocrystals and Nanofibrils Using Highly Recyclable Dicarboxylic Acids

Here we demonstrate potentially low cost and green productions of high thermally stable and carboxylated cellulose nanocrystals (CNCs) and nanofibrils (CNF) from bleached eucalyptus pulp (BEP) and unbleached mixed hardwood kraft pulp (UMHP) fibers using highly recyclable dicarboxylic solid acids. Typical operating conditions were acid concentrations of 50 - 70 wt% at 100 &#176;C for 60 min and 120 &#176;C (no boiling at atmospheric pressure) for 120 min, for BEP and UMHP, respectively. The resultant CNCs have a higher thermal degradation temperature than their corresponding feed fibers and carboxylic acid group content from 0.2 - 0.4 mmol/g. The low strength (high pKa of 1.0 - 3.0) of organic acids also resulted in CNCs with both longer lengths of approximately 239 - 336 nm and higher crystallinity than CNCs produced using mineral acids. Cellulose loss to sugar was minimal. Fibrous cellulosic solid residue (FCSR) from the dicarboxylic acid hydrolysis was used to produce carboxylated CNFs through subsequent mechanical fibrillation with low energy input.

Here we demonstrate a novel method for green and sustainable productions of highly thermally stable and carboxylated cellulose nanocrystals (CNC) and nanofibrils (CNF) using highly recyclable solid dicarboxylic acids.

热稳定和羧基化纤维素纳米晶和纳米原纤维使用高度可回收的二元羧酸绿色和低成本生产

Here we demonstrate potentially low cost and green productions of high thermally stable and carboxylated cellulose nanocrystals (CNCs) and nanofibrils ...

Determination of Carbonyl Functional Groups in Bio-oils by Potentiometric Titration: The Faix Method

Carbonyl compounds present in bio-oils are known to be responsible for bio-oil property changes upon storage and during upgrading. Specifically, carbonyls cause an increase in viscosity (often referred to as &#39;aging&#39;) during storage of bio-oils. As such, carbonyl content has previously been used as a method of tracking bio-oil aging and condensation reactions with less variability than viscosity measurements. Additionally, carbonyls are also responsible for coke formation in bio-oil upgrading processes. Given the importance of carbonyls in bio-oils, accurate analytical methods for their quantification are very important for the bio-oil community. Potentiometric titration methods based on carbonyl oximation have long been used for the determination of carbonyl content in pyrolysis bio-oils. Here, we present a modification of the traditional carbonyl oximation procedures that results in less reaction time, smaller sample size, higher precision, and more accurate carbonyl determinations. While traditional carbonyl oximation methods occur at room temperature, the Faix method presented here occurs at an elevated temperature of 80 &#176;C.

Here we present a potentiometric titration technique for accurately quantifying carbonyl compounds in pyrolysis bio-oils.

该Faix方法:生物油羰基官能团通过电位滴定法测定

Carbonyl compounds present in bio-oils are known to be responsible for bio-oil property changes upon storage and during upgrading. Specifically, carbonyls ...

Application and Methodology of the Non-destructive 19F Time-domain NMR Technique to Measure the Content in Fluorine-containing Drug Products

Here, we describe a protocol developed by our group that uses low-field fluorine-19 (19F) time-domain (TD) nuclear magnetic resonance (NMR) to measure the average content of fluorinated drugs in their formulated drug product forms: tablets or capsules. This method is specific to fluorinated drugs because it detects only the content of fluorine, avoiding interference from the excipients that lack fluorine. The advantages of measuring the active content of fluorinated drugs using low-field 19F TD-NMR versus high-field 19F solid-state (SS) NMR are the simplicity of the method; the low cost; and the non-destructive nature of the technique, with all samples recoverable in intact forms (e.g., powders, tablets, and capsules), making this technique affordable for any laboratory.
We have tested the method with three fluorinated drug products available on the market - cinacalcet, lansoprazole, and ciprofloxacin - with doses ranging from 15 to 500 mg. The results of the analyses, measured by low-field 19F TD-NMR, supported the reported label claims for the average drug content.
Based on the simplicity and reproducibility of the analysis, we envision this methodology being implemented in any laboratory, including manufacturing plants, as a process analytical technology (PAT) tool in the pharmaceutical industry.

Application and Methodology of the Non-destructive 19F Time-domain NMR Technique to Measure the Content in Fluorine-containing Drug Products

A simple and non-destructive technique that measures the average content of drug substances in formulated drug products containing fluorine using low-field fluorine-19 (19F) time-domain (TD) nuclear magnetic resonance (NMR) is presented here. The technique can be applied to the development and manufacturing of drugs in the pharmaceutical industry.

应用程序和非破坏性19F 时间域核磁共振技术的方法来衡量中含氟药物产品的内容

Here, we describe a protocol developed by our group that uses low-field fluorine-19 (19F) time-domain (TD) nuclear magnetic resonance (NMR) to measure the ...

Preparation of N-(2-alkoxyvinyl)sulfonamides from N-tosyl-1,2,3-triazoles and Subsequent Conversion to Substituted Phthalans and Phenethylamines

Decomposition of N-tosyl-1,2,3-triazoles with rhodium(II) acetate dimer in the presence of alcohols forms synthetically versatile N-(2-alkoxyvinyl)sulfonamides, which react under a variety of conditions to afford useful N- and O-containing compounds. Acid-catalyzed addition of alcohols or thiols to N-(2-alkoxyvinyl)sulfonamide-containing phthalans provides access to ketals and thioketals, respectively. Selective reduction of the vinyl group in N-(2-alkoxyvinyl)sulfonamide-containing phthalans via hydrogenation yields the corresponding phthalan in good yield, whereas reduction with sodium bis(2-methoxyethoxy)aluminumhydride generates a ring-opened phenethylamine analogue. Because the N-(2-alkoxyvinyl)sulfonamide functional group is synthetically versatile, but often hydrolytically unstable, this protocol emphasizes key techniques in preparing, handling, and reacting these pivotal substrates in several useful transformations.

Preparation of N-2-alkoxyvinylsulfonamides from N-tosyl-1,2,3-triazoles and Subsequent Conversion to Substituted Phthalans and Phenethylamines

Representative experimental procedures for the synthesis of N-(2-alkoxyvinyl)sulfonamides and subsequent conversion to phthalan and phenethylamine derivatives are presented in detail.

准备n-(2-alkoxyvinyl) 磺胺从n-tosyl-1,2,3-triazoles 和随后转换为取代 Phthalans 和 Phenethylamines

Decomposition of N-tosyl-1,2,3-triazoles with rhodium(II) acetate dimer in the presence of alcohols forms synthetically versatile ...

Preparation of Hollow Polystyrene Particles and Microcapsules by Radical Polymerization of Janus Droplets Consisting of Hydrocarbon and Fluorocarbon Oils

In this article, we have demonstrated a method for producing hollow particles and microcapsules using oil droplets consisting of hydrocarbon oil (styrene) and fluorocarbon oil (perfluoro-n-octane, PFO) in aqueous surfactant (sodium dodecylsulfate, SDS) solutions. Since fluorocarbon oils are immiscible with hydrocarbon oils, the two oils are separated. Emulsions are prepared by stirring styrene/PFO/aqueous SDS solution mixtures at 80 &#176;C. The type of emulsions and the morphology of droplets in the emulsions are observed by light microscope and scanning confocal fluorescence microscope. It is found that oil droplets with Janus-type morphologies consisting of mutually immiscible styrene and PFO are formed in aqueous SDS solutions. Polystyrene particles are fabricated by radical polymerization of the ternary mixtures of styrene/PFO/aqueous SDS solution at 80 &#176;C. The morphologies of the polystyrene are confirmed by scanning electron microscopy and scanning transmission electron microscopy observations. These observations show the preparation of hollow polystyrene particles with a single hole on the surface. To our knowledge, this method is a novel strategy using the immiscibility of hydrocarbon and fluorocarbon oils. The hollow particles can also be applied to the preparation of microcapsules.

A protocol for the fabrication of hollow polymer particles and microcapsules by radical polymerization using emulsions consisting of styrene, perfluoro-n-octane, and aqueous SDS (sodium dodecylsulfate) solution is presented.

由烃类和氟碳油组成的同液滴的自由基聚合制备空心聚苯乙烯颗粒和微胶囊

In this article, we have demonstrated a method for producing hollow particles and microcapsules using oil droplets consisting of hydrocarbon oil (styrene) ...

Employing Pressurized Hot Water Extraction (PHWE) to Explore Natural Products Chemistry in the Undergraduate Laboratory

A recently developed pressurized hot water extraction (PHWE) method which utilizes an unmodified household espresso machine to facilitate natural products research has also found applications as an effective teaching tool. Specifically, this technique has been used to introduce second- and third-year undergraduates to aspects of natural products chemistry in the laboratory. In this report, two experiments are presented: the PHWE of eugenol and acetyleugenol from cloves and the PHWE of seselin and (+)-epoxysuberosin from the endemic Australian plant species Correa reflexa. By employing PHWE in these experiments, the crude clove extract, enriched in eugenol and acetyleugenol, was obtained in 4-9% w/w from cloves by second-year undergraduates and seselin and (+)-epoxysuberosin were isolated in yields of up to 1.1% w/w and 0.9% w/w from C. reflexa by third-year students. The former exercise was developed as a replacement for the traditional steam distillation experiment providing an introduction to extraction and separation techniques, while the latter activity featured guided-inquiry teaching methods in an effort to simulate natural products bioprospecting. This primarily derives from the rapid nature of this PHWE technique relative to traditional extraction methods that are often incompatible with the time constraints associated with undergraduate laboratory experiments. This rapid and practical PHWE method can be used to efficiently isolate various classes of organic molecules from a range of plant species. The complementary nature of this technique relative to more traditional methods has also been demonstrated previously.

Employing Pressurized Hot Water Extraction PHWE to Explore Natural Products Chemistry in the Undergraduate Laboratory

Here, we employ a pressurized hot water extraction (PHWE) method, which utilizes an unmodified household espresso machine to introduce undergraduates to natural products chemistry in the laboratory. Two experiments are presented: PHWE of eugenol and acetyleugenol from cloves and PHWE of seselin and (+)-epoxysuberosin from the Australian plant Correa reflexa.

利用加压热水提取 (phwe) 在本科实验室中探索天然产物化学

A recently developed pressurized hot water extraction (PHWE) method which utilizes an unmodified household espresso machine to facilitate natural products ...

A Two-Step Pyrolysis-Gas Chromatography Method with Mass Spectrometric Detection for Identification of Tattoo Ink Ingredients and Counterfeit Products

Tattoo inks are complex mixtures of ingredients. Each of them possesses different chemical properties which have to be addressed upon chemical analysis. In this method for two-step pyrolysis online coupled to gas chromatography mass spectrometry (py-GC-MS) volatile compounds are analyzed during a first desorption run. In the second run, the same dried sample is pyrolyzed for analysis of non-volatile compounds such as pigments and polymers. These can be identified by their specific decomposition patterns. Additionally, this method can be used to differentiate original from counterfeit inks. Easy screening methods for data evaluation using the average mass spectra and self-made pyrolysis libraries are applied to speed up substance identification. Using specialized evaluation software for pyrolysis GS-MS data, a fast and reliable comparison of the full chromatogram can be achieved. Since GC-MS is used as separation technique, the method is limited to volatile substances upon desorption and after pyrolysis of the sample. The method can be applied for quick substance screening in market control surveys since it requires no sample preparation steps.

This method for two-step pyrolysis online coupled to gas chromatography with mass spectrometric detection and data evaluation protocol can be used for multi-component analysis of tattoo inks and discrimination of counterfeit products.

一种用于检测纹身油墨成分和假冒产品的两步热解-气相色谱法

Tattoo inks are complex mixtures of ingredients. Each of them possesses different chemical properties which have to be addressed upon chemical analysis. ...