这项研究是财政上MH21研究联盟甲烷水合物资源日本经济，贸易和工业部国家甲烷水合物开发计划的支持。笔者想感谢T.前川和S.转到他们与实验的援助。 经许可后转载自数字（村冈，M.，Susuki，N.，山口，H.，辻，T.，山本，Y.，能源燃料，29（3），2015年，1345年至1351年，2015年，DOI: 10.1021 / ef502350n）。版权所有（2015）美国化学学会。

注:请查阅所有相关的材料安全数据表作为本研究采用高压可燃甲烷气体和大型高压容器。戴上头盔，护目镜和防护靴。如果温度控制系统停止，在容器内的压力与氢离解增加而增加。为了防止发生意外，强烈建议使用安全阀系统自动甲烷气体释放到大气中。安全阀系统可以在没有电源供给工作。 1.沙-水-甲烷气体样品9的制备<ol><li>放置高压容器上的振动台上。 </li><li>倾1.5升纯水中水瓶，4000克二氧化硅砂在砂瓶中。准确称取沙子和水的群众在沙和水的瓶子，分别。 </li><li>倒入1升纯水中的高压容器从水瓶2,110 cm 3的内部容积直到水填满半内部容器。 </li><li>打开振动台振动整个容器。设置振动速度和电源以分别为50赫兹和220瓦，。施加振动，直到步骤1.5的完成。通过振动容器移除在容器的底部的漏极线及烧结金属过滤器的残留空气。 </li><li>倾从砂瓶子进入容器3300克硅砂在约1g秒的恒定速率-1使用而整个容器被振动，以确保均匀的填料的水表面附近保持的漏斗。 </li><li>停止振动时水到达容器的边缘。 </li><li>放置一个环作为在容器上，以防止水溢出的边缘暂时壁。 </li><li>在50赫兹和220 W.再次振动该容器</li><li>当沙到达容器（高度140毫米）的边缘，关闭振动。 </li><li>删除使用次临时墙，孔隙水Ë排水管线。倒入孔隙水回水瓶。 </li><li>在50赫兹和300瓦1秒钟一次或两次振动容器包装的沙子，如果需要添加更多的沙子。 </li><li>称取沙子和水的群众在沙和水瓶。计算沙子和水团从沙子和水的瓶子质量差异的船只。在这个实验中，沙子和水的容器中的群众分别3385克和823.6克。的水在容器内的质量被表示为W 总 。 </li><li>覆盖高压容器用不锈钢盖，拧紧对角线相对的对的螺栓序列。 </li><li>从振动台移动至高压容器，以用于实验中的表。 </li><li>覆盖高压容器与热绝缘体，用于控制温度。 </li><li>高压管道和冷却水流线连接到高压容器中。 </li&gt; <li>开的输入和输出的气体管线的阀。在800毫升分钟-1的速度，直至没有过量的水排放入大气压力下的陷阱通风10升甲烷。砂放电被固定在容器的底部的烧结金属过滤器防止。残留的水保留在砂表面上因为亲水硅砂吸附的水分子。 </li><li>权衡的水的质量在陷阱，W 陷阱 ，以确定容器中的气体体积。确定的残留水，W 资源利用公式群众，在血管W¯¯RES = W 总 - 含 陷阱 。在这种情况下，W 水库以及w 阱分别360.6克和463.0克。 </li><li> V 砂 / V 细胞 ，其中V 沙 T的音量-使用公式Ѱ= 1确定样品的孔隙率由砂质量与砂密度（ 即 ，ρS =2630公斤米-3），和V 细胞的比率来确定他沙是在容器的内部容积。样品的孔隙率Ѱ为0.39。 </li><li>关闭输出天然气管线的阀门。注入甲烷，以增加甲烷的孔隙压力在容器到约1210兆帕，在室温（ 即 31.6℃）。 </li><li>关闭输入气体管线的阀。 </li><li>开始使用数据记录器在实验过程中记录在容器内的压力和温度。数据采样的时间间隔为5秒。总的实验时间约为3000分钟。 </li></ol> 2. MH合成和热性能"过冷样品9测量<ol><li>打开冷却器用于通过循环冷却剂从室温容器冷却至2.0℃。让我们从冷却器T中的冷却液循环Ó容器的底部，从那里到容器的盖子，并最后返回到冷却器。在容器中的温度变化率约为0.001℃，秒-1。 </li><li>设置使用TPS分析软件测量参数。设置传感器类型传感器设计＃7577。设置的输出功率W 0至30毫瓦和测量时间为5秒。请注意，如果传感器类型或样品条件改变相应参数应该改变。设置参数以从1℃的提高温度至1.5℃。 </li><li>计算过冷，ΔTSUP，用下面的方程式的程度: SUPΔT= T EQ（P） - T的。 （3） Ť 当量 （P）为MH的平衡温度为压力P的函数Ť 当量 （P）的是使用CSMGem软件1进行计算。0; P和T是通过使用压力和温度计，分别测量该容器中的压力和温度。 </li><li>使用TPS分析器后ΔTSUP大于2℃同时测量热导率，热扩散率，和体积比热。 </li><li>切换连接到每个测量后的热性能分析器TPS的探针。开关实验9在TPS探头和手动分析仪之间的电缆。连接图显示在图中的S2参考9。每个传感器的切换顺序是否定的。 6→2→7→5→1→9→4→3→8→6 ...。该序列是根据在传感器之间的距离，这是设置尽可能防止影响测量的余热。收集数据每3-5分钟。 </li><li>重复测量，直到＆＃916;吨燮 达到200°再次℃。在该实验中，ΔŤSUP最初随着时间而增加。后ΔTSUP达到最大值，因为压力带MH的形成减小ΔTSUP逐渐减小到0℃。检查，如果ΔTSUP是之前使用等式3在TPS测量大于2℃。 </li><li>确保该温度分布不受MH熔化。如果氢在测量过程中熔化时，温度不会增加，因为氢的熔化是吸热反应。在测量过程中检查的温度分布，并在结果部分进行了讨论。 </li><li>使用TPS技术，所有的温度分布的数据进行热性能"分析。 </li></ol> 3.样品9,11的饱和度变化的计算注意:饱和为氢，水和气体的样品作为时间t的函数的程度使用的气体的状态方程来计算。所使用的计算的细节和方程先前所述11。 <ol><li>计算出的甲烷气体体积V 气体 ， 叔在时间t <img alt="公式4" src="/files/ftp_upload/53956/53956eq4.jpg" /> 其中Q是气体的容器中的初始体积V MH，叔- 1是氢的在时刻t的体积- 1，和R VHW是水和MH的体积比。 <img alt="公式5" src="/files/ftp_upload/53956/53956eq5.jpg" /> 在公式5 中，n是MH的水合数（〜6），ρMH，ρ 水分别对应于氢和水的密度，以及w MH和w的 水表示氢和水，r的分子质量espectively。 </li><li>计算量ΔM 吨 （摩尔）MH的从T形成- 1到T <img alt="公式6" src="/files/ftp_upload/53956/53956eq6.jpg" /> 其中，R是气体常数，P为甲烷气体的压力，和Z 吨 （T 气体 ，T，P 的气体 ，t）是甲烷的在时刻t的压缩系数。我们9和坂本等 11所使用的本尼迪克特-韦布-鲁宾（BWR）方程，Lee和凯斯勒改性，计算ž 牛逼 12，13。对于这个计算，公式（3-7.1） - 7参考13 - BWR的13式和李-凯斯勒常数（3-7.4）在表3中。 </li><li>计算体积变化ΔV MH， <suB&gt;从T MH的笔- 1到T <img alt="公式7" src="/files/ftp_upload/53956/53956eq7.jpg" /> 其中P 小号 是101325 Pa的基准压力，T s是273.15 K时的基准温度中，Z s是在P点S中的压缩系数和T 秒 （ŽS〜1）和V CH 4是在甲烷气体体积的比率MH的单位体积[米3米-3。使用的165.99为V CH4值[米3米-3。 </li><li>计算体积V MH， 叔 MH的在时间t <img alt="式（8）" src="/files/ftp_upload/53956/53956eq8.jpg" /></li><li>计算水中v 水在压力容器的体积， 叔在时间t <img alt="公式9" src="/files/ftp_upload/53956/53956eq9.jpg" /&gt; 其中V 水，1是水的初始体积。 </li><li>重复使用公式计算。 4-9在时间t = 2，3，...，以确定在水，甲烷，和MH 11的饱和的变化。初始条件为t = 1， 即 ，V 气体 ，1 = Q。 t时刻的P和T是从数据日志9服用。计算结果示于下面的部分。 </li></ol>

<ol>
	<li>Sloan, E. D., Koh, C. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Clathrate Hydrates of Natural Gases, 3rd ed. , (2007).</li><li>Hatzikiriakos, S. G., Englezos, P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+relationship+between+global+warming+and+methane+gas+hydrates+in+the+earth.">The relationship between global warming and methane gas hydrates in the earth.</a> Chem. Eng. Sci. 48 (23), 3963-3969 (1993).</li><li>Yamamoto, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Overview+and+introduction:+pressure+core-sampling+and+analyses+in+the+2012-2013+MH21+offshore+test+of+gas+production+from+methane+hydrates+in+the+eastern+Nankai+Trough.">Overview and introduction: pressure core-sampling and analyses in the 2012-2013 MH21 offshore test of gas production from methane hydrates in the eastern Nankai Trough.</a> Mar. Petrol. Geol. 66 (Pt 2), 296 (2015).</li><li>Fujii, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Geological+setting+and+characterization+of+a+methane+hydrate+reservoir+distributed+at+the+first+offshore+production+test+site+on+the+Daini-Atsumi+Knoll+in+the+eastern+Nankai+Trough,+Japan.">Geological setting and characterization of a methane hydrate reservoir distributed at the first offshore production test site on the Daini-Atsumi Knoll in the eastern Nankai Trough, Japan.</a> Mar. Petrol. Geol. 66 (Pt 2), 310 (2015).</li><li>Mao, W. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hydrogen+clusters+in+clathrate+hydrate.">Hydrogen clusters in clathrate hydrate.</a> Science. 297 (5590), 2247-2249 (2002).</li><li>Lee, S., Liang, L., Riestenberg, D., West, O. R., Tsouris, C., Adams, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=CO2+hydrate+composite+for+ocean+carbon+sequestration.">CO2 hydrate composite for ocean carbon sequestration.</a> Environ. Sci. Technol. 37 (16), 3701-3708 (2003).</li><li>Muromachi, S., Ohmura, R., Takeya, S., Mori, H. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Clathrate+Hydrates+for+Ozone+Preservation.">Clathrate Hydrates for Ozone Preservation.</a> J. Phys. Chem. B. 114, 11430-11435 (2010).</li><li>Waite, W. F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Physical+properties+of+hydrate-bearing+sediments.">Physical properties of hydrate-bearing sediments.</a> Rev. Geophys. 47 (4), (2009).</li><li>Muraoka, M., Susuki, N., Yamaguchi, H., Tsuji, T., Yamamoto, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thermal+properties+of+a+supercooled+synthetic+sand-water-gas-methane+hydrate+sample.">Thermal properties of a supercooled synthetic sand-water-gas-methane hydrate sample.</a> Energy Fuels. 29 (3), 1345-1351 (2015).</li><li>Gustafsson, S. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transient+plane+source+techniques+for+thermal+conductivity+and+thermal+diffusivity+measurements+of+solid+materials.">Transient plane source techniques for thermal conductivity and thermal diffusivity measurements of solid materials.</a> Rev. Sci. Instrum. 62 (3), 797-804 (1991).</li><li>Sakamoto, Y., Haneda, H., Kawamura, T., Aoki, K., Komai, T., Yamaguchi, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Experimental+Study+on+a+New+Enhanced+Gas+Recovery+Method+by+Nitrogen+Injection+from+a+Methane+Hydrate+Reservoir.">Experimental Study on a New Enhanced Gas Recovery Method by Nitrogen Injection from a Methane Hydrate Reservoir.</a> J. MMIJ. 123 (8), 386-393 (2007).</li><li>Lee, B. I., Kesler, M. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+generalized+thermodynamic+correlation+based+on+three-parameter+corresponding+states.">A generalized thermodynamic correlation based on three-parameter corresponding states.</a> AIChE J. 21 (3), 510-527 (1975).</li><li>Reid, R. C., Prausnitz, J. M., Poling, B. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Chapter+3,+Unit+3,+7.">Chapter 3, Unit 3, 7.</a> The properties of gases and liquids. , 47-49 (1987).</li><li>Anderson, G. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Enthalpy+of+dissociation+and+hydration+number+of+methane+hydrate+from+the+Clapeyron+equation.">Enthalpy of dissociation and hydration number of methane hydrate from the Clapeyron equation.</a> J. Chem. Thermodyn. 36 (12), 1119-1127 (2004).</li><li>Waite, W. F., deMartin, B. J., Kirby, S. H., Pinkston, J., Ruppel, C. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thermal+conductivity+measurements+in+porous+mixtures+of+methane+hydrate+and+quartz+sand.">Thermal conductivity measurements in porous mixtures of methane hydrate and quartz sand.</a> Geophys. Res. Lett. 29 (24), 82-1-82-4 (2002).</li><li>Kumar, P., Turner, D., Sloan, E. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thermal+diffusivity+measurements+of+porous+methane+hydrate+and+hydrate-sediment+mixtures.">Thermal diffusivity measurements of porous methane hydrate and hydrate-sediment mixtures.</a> J. Geophys. Res. 109 (B1), (2004).</li><li>Huang, D., Fan, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Measuring+and+modeling+thermal+conductivity+of+gas+hydrate-bearing+sand.">Measuring and modeling thermal conductivity of gas hydrate-bearing sand.</a> J. Geophys. Res. 110 (B1), (2005).</li></ol>

The authors have nothing to disclose.

估计MH的测量形成热的影响。 MH的形成热量从中文变化率的产品估计， 如图3b和形成H = 52.9千焦摩尔-1 MH 14的焓。因此，最高温度变化是0.00081℃，秒-1。这是比5秒的时间间隔期间1℃，1.5℃之间的TPS传感器的温度上升ΔTÇ低得多。详细的估计和讨论二段描述。 4参考9。 以下是至关重要的协议的步?...

天然气水合物是包含含有在轿厢1客体分子氢键的水分子的笼形结构的结晶化合物。在海底和永久冻土地区的甲烷水合物（MHS）的大量非常有趣的未来能源资源，但可能会影响到全球的气候条件2。 2013年3月，日本石油，天然气和金属国家公司进行了世界上第一个海上生产测试，使用了"减压法"3,4东部南海海槽自然承载MH沉积物中提取气体。 气体水合物可以存储气体，例如甲烷1，氢5，CO 2 1,6，和臭氧7。因此，甲烷和氢气水合物研究作为势能储存和运输介质。为了减少二氧化碳释放到大气中，CO 2 seques 2排放使用二氧化碳在深海沉积物2水合物tration进行了研究6。臭氧是目前在水净化和食品杀菌使用。臭氧保鲜技术的研究已进行了，因为它是化学上不稳定7。在水合物的臭氧浓度是在臭氧化水或冰7比要高得多。 为了开发天然含MH沉积物和基于水合物技术的天然气产量，就必须了解天然气水合物的热性能。然而，气体水合物含沉积物的热性质数据和模型研究很少8。 的"减压方法"可用于通过减少低于水合物稳定的孔隙压力以解离氢的沉积物孔隙空间。在这个过程中，沉淀物的孔隙空间的分量，从水和氢水，氢，和气体发生变化。热性能"测量后者条件是困难的，因为氢的熔化热可能会影响测量结果。为了解决这个问题，村冈等在氢形成9进行热性质"测量在过冷的条件。 与此视频协议中，我们解释过冷合成砂水煤气氢样品的测定方法。 图1示出用于测量人工甲烷水合物轴承沉积物的热性能的实验装置。安装是如图参考9相同。该系统主要包括一高压容器中，压力和温度的控制，以及测量系统的热性能。高压容器用140毫米的内径为140毫米的高度由圆柱形不锈钢的;其与死体积除去内部容积是2110厘米3，而其压力限制为15兆帕。该transie<html> nt的平面源（TPS）技术被用于测量热性能10。九与2.001毫米个人半径TPS探头放入容器内。九个探针9的布局示于图2中的参考9。在TPS探针被连接到热性能&#39;分析器用电缆和在实验过程中手动切换。在TPS传感器，连接图，和设置在容器的细节示于图S1中 ，图2和的支持信息3中参考9。 <img alt="图1" src="/files/ftp_upload/53956/53956fig1.jpg" /> 图1:该实验装置用于测量所述人工甲烷水合物轴承沉积物的热性能的数字是从参考9修改。3956fig1large.jpg"目标="_空白"&gt;点击此处查看该图的放大版本。 使用了TPS方法测量每个样品的热性能。该方法的原则在参照图10进行说明。在该方法中，依赖于时间的温度上升，ΔTAVE，是<img alt="式（1）" src="/files/ftp_upload/53956/53956eq1.jpg" />哪里<img alt="公式（2）" src="/files/ftp_upload/53956/53956eq2.jpg" />在等式1中，W 0是来自传感器的输出功率，r是传感器探头的半径，λ是样品的热导率，α为热扩散率，t是从电源供给开始的时间到传感器探头。D（τ）是一个无量纲时间相关的功能。τ </青霉&gt;由（αT/ R）1/2给出。在等式2中，m是TPS探针的同心环的数量和I 0是一个修正贝塞尔函数。样品的热导率，热扩散率和比热同时由施加到作为电源被供给到传感器探头的温度上升反演分析确定。

<table border="0" cellpadding="0" cellspacing="0" width="1353">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:444px;">TPS thermal probe, Hot disk sensor</td>
			<td style="width:251px;">Hot Disk AB Co., Sweden</td>
			<td style="width:267px;">#7577</td>
			<td style="width:392px;">Kapton sensor type, sensor radius 2.001 mm</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:444px;">Hot disk thermal properties analyzer</td>
			<td>Hot Disk AB Co., Sweden</td>
			<td style="width:267px;">TPS 2500&#160;</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:444px;">Toyoura standard silica sand</td>
			<td style="width:251px;">Toyoura Keiseki Kogyo Co., Ltd., Japan</td>
			<td style="width:267px;">N/A</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:444px;">Methane gas ,99.9999%</td>
			<td style="width:251px;">Tokyo Gas Chemicals Co., Ltd., Japan</td>
			<td style="width:267px;">N/A</td>
			<td>Grade 6N, Volume 47L, Charging pressure 14.7MPa</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:444px;">Water Purification System,Elix Advantage 3&#160;</td>
			<td style="width:251px;">Merck Millipore., U.S.</td>
			<td style="width:267px;">N/A</td>
			<td>5 M&#937; cm (at 25&#176;C) resistivity</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:444px;">Vibrating table, Vivratory packer</td>
			<td style="width:251px;">Sinfonia Technology Co. Ltd., Japan</td>
			<td style="width:267px;">VGP-60</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:444px;">Chiller, Thermostatic Bath Circulator&#160;</td>
			<td style="width:251px;">THOMAS KAGAKU Co., Ltd., Japan</td>
			<td style="width:267px;">TRL-40SP</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:444px;">Coorant, Aurora brine</td>
			<td style="width:251px;">Tokyo Fine Chemical Co.,Ltd., Japan</td>
			<td style="width:267px;">N/A</td>
			<td>ethylene glycol 71wt%</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:444px;">Temparature gage</td>
			<td style="width:251px;">Nitto Kouatsu., Japan</td>
			<td style="width:267px;">N/A</td>
			<td>Pt 100, sheath-type platinum resistance temperature detector</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:444px;">Pressure gage</td>
			<td style="width:251px;">Kyowa Electronic Instruments., Japan</td>
			<td style="width:267px;">PG-200 KU</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:444px;">Data logger</td>
			<td style="width:251px;">KEYENCE., Japan</td>
			<td style="width:267px;">NR-500</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:444px;">Mass flow controller</td>
			<td style="width:251px;">OVAL Co., Japan</td>
			<td style="width:267px;">F-221S-A-11-11A</td>
			<td>Maximum flow 2000 Nml/M, maximum design pressure 19.6 MPa</td>
		</tr>
	</tbody>
</table>

protocol for measuring the thermal properties of a supercooled synthetic sand-water-gas-methane hydrate sample

Methane hydrates (MHs) are present in large amounts in the ocean floor and permafrost regions. Methane and hydrogen hydrates are being studied as future energy resources and energy storage media. To develop a method for gas production from natural MH-bearing sediments and hydrate-based technologies, it is imperative to understand the thermal properties of gas hydrates.
The thermal properties' measurements of samples comprising sand, water, methane, and MH are difficult because the melting heat of MH may affect the measurements. To solve this problem, we performed thermal properties' measurements at supercooled conditions during MH formation. The measurement protocol, calculation method of the saturation change, and tips for thermal constants' analysis of the sample using transient plane source techniques are described here.
The effect of the formation heat of MH on measurement is very small because the gas hydrate formation rate is very slow. This measurement method can be applied to the thermal properties of the gas hydrate-water-guest gas system, which contains hydrogen, CO2, and ozone hydrates, because the characteristic low formation rate of gas hydrate is not unique to MH. The key point of this method is the low rate of phase transition of the target material. Hence, this method may be applied to other materials having low phase-transition rates.

图2a示出了不受MH熔化。ΔTc是温度的变化，由于热常数&#39;测量的温度分布; 图2b示出了由氢熔化影响的温度分布。在图2b的配置文件不能通过方程1和2进行分析，因为这些方程通过假设稳定样品条件的。 图3a示出的压力，温度，和在容器中作为时间的函数过冷却...

Watch this Scientific Journal Video about Protocol for Measuring the Thermal Properties of a Supercooled Synthetic Sand-water-gas-methane Hydrate Sample at JoVE.com

Protocol for Measuring the Thermal Properties of a Supercooled Synthetic Sand-water-gas-methane Hydrate Sample

We present a protocol for measuring the thermal properties of synthetic hydrate-bearing sediment samples comprising sand, water, methane, and methane hydrate.

协议测量过冷的合成砂水 - 气 - 甲烷水合物样品的热性能

Methane hydrates (MHs) are present in large amounts in the ocean floor and permafrost regions. Methane and hydrogen hydrates are being studied as future ...

protocol-for-measuring-thermal-properties-supercooled-synthetic-sand

Research

JoVE Journal

Environment

8.8K 次观看.  National Institute of Advanced Industrial Science and Technology (AIST). We present a protocol for measuring the thermal properties of synthetic hydrate-bearing sediment samples comprising sand, water, methane, and methane hydrate.

视频: Protocol for Measuring the Thermal Properties of a Supercooled Synthetic Sand-water-gas-methane Hydrate Sample

Optimized Negative Staining: a High-throughput Protocol for Examining Small and Asymmetric Protein Structure by Electron Microscopy

Structural determination of proteins is rather challenging for proteins with molecular masses between 40 - 200 kDa. Considering that more than half of natural proteins have a molecular mass between 40 - 200 kDa1,2, a robust and high-throughput method with a nanometer resolution capability is needed. Negative staining (NS) electron microscopy (EM) is an easy, rapid, and qualitative approach which has frequently been used in research laboratories to examine protein structure and protein-protein interactions. Unfortunately, conventional NS protocols often generate structural artifacts on proteins, especially with lipoproteins that usually form presenting rouleaux artifacts. By using images of lipoproteins from cryo-electron microscopy (cryo-EM) as a standard, the key parameters in NS specimen preparation conditions were recently screened and reported as the optimized NS protocol (OpNS), a modified conventional NS protocol 3 . Artifacts like rouleaux can be greatly limited by OpNS, additionally providing high contrast along with reasonably high&#8208;resolution (near 1 nm) images of small and asymmetric proteins. These high-resolution and high contrast images are even favorable for an individual protein (a single object, no average) 3D reconstruction, such as a 160 kDa antibody, through the method of electron tomography4,5. Moreover, OpNS can be a high&#8208;throughput tool to examine hundreds of samples of small proteins. For example, the previously published mechanism of 53 kDa cholesteryl ester transfer protein (CETP) involved the screening and imaging of hundreds of samples 6. Considering cryo-EM rarely successfully images proteins less than 200 kDa has yet to publish any study involving screening over one hundred sample conditions, it is fair to call OpNS a high-throughput method for studying small proteins. Hopefully the OpNS protocol presented here can be a useful tool to push the boundaries of EM and accelerate EM studies into small protein structure, dynamics and mechanisms.

More than half of proteins are small proteins (molecular mass &#60;200 kDa) that are challenging for both electron microscope imaging and three-dimensional reconstructions. Optimized negative staining is a robust and high-throughput protocol to obtain high contrast and relatively high resolution (~1 nm) images of small asymmetric proteins or complexes under different physiological conditions.

优化负染:通过电子显微镜检查小和不对称蛋白结构的高通量协议

Structural determination of proteins is rather challenging for proteins with molecular masses between 40 - 200 kDa. Considering that more than half of ...

科研

环境科学

Transient Gene Expression in Tobacco using Gibson Assembly and the Gene Gun

In order to target a single protein to multiple subcellular organelles, plants typically duplicate the relevant genes, and express each gene separately using complex regulatory strategies including differential promoters and/or signal sequences. Metabolic engineers and synthetic biologists interested in targeting enzymes to a particular organelle are faced with a challenge: For a protein that is to be localized to more than one organelle, the engineer must clone the same gene multiple times. This work presents a solution to this strategy: harnessing alternative splicing of mRNA. This technology takes advantage of established chloroplast and peroxisome targeting sequences and combines them into a single mRNA that is alternatively spliced. Some splice variants are sent to the chloroplast, some to the peroxisome, and some to the cytosol. Here the system is designed for multiple-organelle targeting with alternative splicing. In this work, GFP was expected to be expressed in the chloroplast, cytosol, and peroxisome by a series of rationally designed 5&#8217; mRNA tags. These tags have the potential to reduce the amount of cloning required when heterologous genes need to be expressed in multiple subcellular organelles. The constructs were designed in previous work11, and were cloned using Gibson assembly, a ligation independent cloning method that does not require restriction enzymes. The resultant plasmids were introduced into Nicotiana benthamiana epidermal leaf cells with a modified Gene Gun protocol. Finally, transformed leaves were observed with confocal microscopy.

This work describes a novel method for selectively targeting subcellular organelles in plants, assayed using the BioRad Gene Gun.

使用吉布森大会和基因枪烟草中瞬时基因表达

In order to target a single protein to multiple subcellular organelles, plants typically duplicate the relevant genes, and express each gene separately ...

Experimental Protocol for Manipulating Plant-induced Soil Heterogeneity

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

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

用于操纵植物诱导土壤异质性的实验协议

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

An Optimized Enrichment Technique for the Isolation of Arthrobacter Bacteriophage Species from Soil Sample Isolates

Bacteriophage isolation from environmental samples has been performed for decades using principles set forth by pioneers in microbiology. The isolation of phages infecting Arthrobacter hosts has been limited, perhaps due to the low success rate of many previous isolation techniques, resulting in an underrepresented group of Arthrobacter phages available for study. The enrichment technique described here, unlike many others, uses a filtered extract free of contaminating bacteria as the base for indicator bacteria growth, Arthrobactersp. KY3901, specifically. By first removing soil bacteria the target phages are not hindered by competition with native soil bacteria present in initial soil samples. This enrichment method has resulted in dozens of unique phages from several different soil types and even produced different types of phages from the same enriched soil sample isolate. The use of this procedure can be expanded to most nutrient rich aerobic media for the isolation of phages in a vast diversity of interesting host bacteria.

An Optimized Enrichment Technique for the Isolation of Arthrobacter Bacteriophage Species from Soil Sample Isolates

We present an enrichment protocol for the isolation of bacteriophages infecting bacteria in the Arthrobacter genus. This enrichment protocol produces fast and reproducible results for the isolation and amplification of Arthrobacter phages from soil isolates.

一种优化富集技术的隔离<em&gt;节杆菌</em&gt;噬菌体种从土壤样品隔离

Bacteriophage isolation from environmental samples has been performed for decades using principles set forth by pioneers in microbiology. The isolation of ...

A New Application of the Electrical Penetration Graph (EPG) for Acquiring and Measuring Electrical Signals in Phloem Sieve Elements

Electrophysiological properties of cells are often studied in vitro, after dissociating them from their native environments. However, the study of electrical transmission between distant cells in an organism requires in vivo, artifact-free recordings of cells embedded within their native environment. The transmission of electrical signals from wounded to unwounded areas in a plant has since long piqued the interest of botanists. The phloem, the living part of the plant vasculature that is spread throughout the plant, has been postulated as a major tissue in electrical transmission in plants. The lack of suitable electrophysiological methods poses many challenges for the study of the electrical properties of the phloem cells in vivo. Here we present a novel approach for intracellular electrophysiology of sieve elements (SEs) that uses living aphids, or other phloem-feeding hemipteran insects, integrated in the electrical penetration graph (EPG) circuit. The versatility, robustness, and accuracy of this method made it possible to record and study in detail the wound-induced electrical signals in SEs of central veins of the model plant Arabidopsis thaliana1. Here we show that EPG-electrodes can be easily implemented for intracellular electrophysiological recordings of SEs in marginal veins, as well as to study the capacity of SEs to respond with electrical signals to several external stimuli. The EPG approach applied to intracellular electrophysiology of SEs can be implemented to a wide variety of plant species, in a large number of plant/insect combinations, and for many research aims.

A New Application of the Electrical Penetration Graph EPG for Acquiring and Measuring Electrical Signals in Phloem Sieve Elements

Electrical Penetration Graph (EPG) is a well-established technique for studying the feeding behavior of stylet-bearing insects. Here we show a new application of EPG as a non-invasive tool for the acquisition of intracellular electrophysiology recordings of sieve elements (SEs), the cells that form the phloem vasculature in plants.

在电气贯穿图（EPG）的韧皮部筛分子获取和测量电信号中的新应用

Electrophysiological properties of cells are often studied in vitro, after dissociating them from their native environments. However, the study of ...

A Protocol for Collecting and Constructing Soil Core Lysimeters

Leaching of nutrients from land applied fertilizers and manure used in agriculture can lead to accelerated eutrophication of surface water. Because the landscape has complex and varied soil morphology, an accompanying disparity in flow paths for leachate through the soil macropore and matrix structure is present. The rate of flow through these paths is further affected by antecedent soil moisture. Lysimeters are used to quantify flow rate, volume of water and concentration of nutrients leaching downward through soils. While many lysimeter designs exist, accurately determining the volume of water and mass balance of nutrients is best accomplished with bounded lysimeters that leave the natural soil structure intact. 
Here we present a detailed method for the extraction and construction of soil core lysimeters equipped with soil moisture sensors at 5 cm and 25 cm depths. Lysimeters from four different Coastal Plain soils (Bojac, Evesboro, Quindocqua and Sassafras) were collected on the Delmarva Peninsula and moved to an indoor climate controlled facility. Soils were irrigated once weekly with the equivalent of 2 cm of rainfall to draw down soil nitrate-N concentrations. At the end of the draw down period, poultry litter was applied (162 kg TN ha-1) and leaching was resumed for an additional five weeks. Total recovery of applied irrigation water varied from 71% to 85%. Nitrate-N concentration varied over the course of the study from an average of 27.1 mg L-1 before litter application to 40.3 mg L-1 following litter application. While greatest flux of nutrients was measured in soils dominated by coarse sand (Sassafras) the greatest immediate flux occurred from the finest textured soil with pronounced macropore development (Quindocqua).

A detailed method for extraction and assembly of intact soil core lysimeters and their use for study of leachate and associated loss of nutrients from surface applied poultry litter is demonstrated.

一种用于收集和构建土芯协议测渗计

Leaching of nutrients from land applied fertilizers and manure used in agriculture can lead to accelerated eutrophication of surface water. Because the ...

Protocol for Microplastics Sampling on the Sea Surface and Sample Analysis

Microplastic pollution in the marine environment is a scientific topic that has received increasing attention over the last decade. The majority of scientific publications address microplastic pollution of the sea surface. The protocol below describes the methodology for sampling, sample preparation, separation and chemical identification of microplastic particles. A manta net fixed on an &#187;A frame&#171; attached to the side of the vessel was used for sampling. Microplastic particles caught in the cod end of the net were separated from samples by visual identification and use of stereomicroscopes. Particles were analyzed for their size using an image analysis program and for their chemical structure using ATR-FTIR and micro FTIR spectroscopy. The described protocol is in line with recommendations for microplastics monitoring published by the Marine Strategy Framework Directive (MSFD) Technical Subgroup on Marine Litter. This written protocol with video guide will support the work of researchers that deal with microplastics monitoring all over the world.

The protocol below describes the methodology for: microplastics sampling on the sea surface, separation of microplastic and chemical identification of particles. This protocol is in line with the recommendations for microplastics monitoring published by the MSFD Technical Subgroup on Marine Litter.

协议塑料微粒采样的海面和样品分析

Microplastic pollution in the marine environment is a scientific topic that has received increasing attention over the last decade. The majority of ...

Thermal Scanning Conductometry (TSC) as a General Method for Studying and Controlling the Phase Behavior of Conductive Physical Gels

The thermal scanning conductometry protocol is a new approach in studying ionic gels based on low molecular weight gelators. The method is designed to follow the dynamically changing state of the ionogels, and to deliver more information and details about the subtle change of conductive properties with an increase or decrease in the temperature. Moreover, the method allows the performance of long term (i.e. days, weeks) measurements at a constant temperature to investigate the stability and durability of the system and the aging effects. The main advantage of the TSC method over classical conductometry is the ability to perform measurements during the gelation process, which was impossible with the classical method due to temperature stabilization, which usually takes a long time before the individual measurement. It is a well-known fact that to obtain the physical gel phase, the cooling stage must be fast; moreover, depending on the cooling rate, different microstructures can be achieved. The TSC method can be performed with any cooling/heating rate that can be assured by the external temperature system. In our case, we can achieve linear temperature change rates between 0.1 and approximately 10 &#176;C/min. The thermal scanning conductometry is designed to work in cycles, continuously changing between heating and cooling stages. Such an approach allows study of the reproducibility of the thermally reversible gel-sol phase transition. Moreover, it allows the performance of different experimental protocols on the same sample, which can be refreshed to initial state (if necessary) without removal from the measuring cell. Therefore, the measurements can be performed faster, in a more efficient way, and with much higher reproducibility and accuracy. Additionally, the TSC method can be also used as a tool to manufacture the ionogels with targeted properties, like microstructure, with an instant characterization of conductive properties.

Thermal Scanning Conductometry TSC as a General Method for Studying and Controlling the Phase Behavior of Conductive Physical Gels

The kinetics of the cooling process defines the properties of ionic gels based on low molecular weight gelators. This manuscript describes the usage of thermal scanning conductometry (TSC), which obtains full control over the gelation process, along with in situ measurements of the samples' temperature and conductivity.

热扫描电导 (TSC) 作为研究和控制导电物理凝胶相行为的一般方法

The thermal scanning conductometry protocol is a new approach in studying ionic gels based on low molecular weight gelators. The method is designed to ...

The Hawaii Protocol for Scientific Monitoring of Coffee Berry Borer: a Model for Coffee Agroecosystems Worldwide

Coffee berry borer (CBB) is the most devastating insect pest for coffee crops worldwide. We developed a scientific monitoring protocol that is aimed at capturing and quantifying the dynamics and impact of this invasive insect pest as well as the development of its host plant across a heterogeneous landscape. The cornerstone of this comprehensive monitoring system is timely georeferenced data collection on CBB movement, coffee berry infestation, mortality by the fungus Beauveria bassiana, and coffee plant phenology via a mobile electronic data recording application. This electronic data collection system allows field records to be georeferenced through built-in global positioning systems, and is backed by a network of weather stations and records of farm management practices. Comprehensive monitoring of CBB and host plant dynamics is an essential part of an area-wide project in Hawaii to aggregate landscape-level data for research to improve management practices. Coffee agroecosystems in other parts of the world that experience highly variable environmental and socioeconomic factors will also benefit from implementing this protocol, in that it will drive the development of customized integrated pest management (IPM) to manage CBB populations.

Comprehensive monitoring of coffee berry borer and host plant dynamics is essential for aggregating landscape-level data to improve management of this invasive pest. Here, we present a protocol for scientific monitoring of coffee berry borer movement, infestation, mortality, coffee plant phenology, weather, and farm management via a mobile electronic data recording application.

夏威夷咖啡莓科学监测协议: 全球咖啡农田模型

Coffee berry borer (CBB) is the most devastating insect pest for coffee crops worldwide. We developed a scientific monitoring protocol that is aimed at ...

High-throughput, Microscale Protocol for the Analysis of Processing Parameters and Nutritional Qualities in Maize (Zea mays L.)

Maize is an important grain crop in the United States and worldwide. However, maize grain must be processed prior to human consumption. Furthermore, whole grain composition and processing characteristics vary among maize hybrids and can impact the quality of the final processed product. Therefore, in order to produce healthier processed food products from maize, it is necessary to know how to optimize processing parameters for particular sets of germplasm to account for these differences in grain composition and processing characteristics. This includes a better understanding of how current processing techniques impact the nutritional quality of the final processed food product. Here, we describe a microscale protocol that both simulates the processing pipeline to produce cornflakes from large flaking grits and allows for the processing of multiple grain samples simultaneously. The flaking grits, the intermediate processed products, or final processed product, as well as the corn grain itself, can be analyzed for nutritional content as part of a high-throughput analytical pipeline. This procedure was developed specifically for incorporation into a maize breeding research program, and it can be modified for other grain crops. We provide an example of the analysis of insoluble-bound ferulic acid and p-coumaric acid content in maize. Samples were taken at five different processing stages. We demonstrate that sampling can take place at multiple stages during microscale processing, that the processing technique can be utilized in the context of a specialized maize breeding program, and that, in our example, most of the nutritional content was lost during food product processing.

High-throughput, Microscale Protocol for the Analysis of Processing Parameters and Nutritional Qualities in Maize Zea mays L.

Here, we present a microscale protocol for processing grain samples and for incorporating this microscale approach into a high-throughput analytical pipeline. This is a higher throughput adaptation of currently available protocols.

玉米加工参数和营养品质分析的高通量、微尺度协议 (玉蜀黍)

Maize is an important grain crop in the United States and worldwide. However, maize grain must be processed prior to human consumption. Furthermore, whole ...