Thermal-Conductivity-Enhancing Copper-Plated Expanded Graphite/Paraffin Composite for Highly Stable Phase-Change Materials

Paraffin (PA)/expanded graphite (EG) is an important composite phase change material with low cost, high heat storage, good thermal conductivity and cycling stability. Its thermal conductivity needs to be further improved for application in the thermal management system of power lithium-ion batteries. In this paper, copper plated expanded graphite (CPEG) with 3D porous structure was prepared by electroless copper plating method, which was used as thermal conductivity enhancing material to replace part of EG in PA/EG composite materials. For the optimized phase change material composed of 80 %PA-14 %EG-6 %CPEG, the copper content is very low (0.768 wt %), but its thermal conductivity can be significantly improved without loss of latent heat and thermal cycling stability. Its thermal conductivity is increased from 11 times to 16.5 times that of paraffin while compared with the copper-free composite material (80 %PA-20 %EG). The PA/EG/CPEG composite material exhibits good temperature control effect on power lithium-ion batteries.     

石蜡微胶囊的制备

针对太阳能利用以及一些蓄热场合,通过示差扫描量热法（DSC）选取了合适的石蜡,以脲醛树脂为囊壁,采用原位聚合法制备了石蜡一脲醛树脂微胶囊,拟将此微胶囊添加到上述应用场合的传热流体中,提高传热流体的热容。实验结果表明,乳化剂OP更适合于熔点60℃石蜡微胶囊的制备。     

Determination of the upper limits, benchmarks, and critical properties for gas separations using stabilized room temperature ionic liquid membranes (SILMs) for the purpose of guiding future research

The literature reports that supported ionic liquid membranes (SILMs) outperform standard polymers for the separations of CO₂/N₂ and CO₂/CH₄, even under continuous flow mixed gas conditions. Before the expenditure of more resources to develop new room temperature ionic liquids (RTILs) and SILMs, it is time to consider what benchmarks for SILM performance exist and if upper limits could be projected based on the physical chemistry of RTILs. At this juncture, we should ask if the current research efforts are properly focused based on the successes and failures in the literature. We summarize literature data, along with adding new data, on the SILM permeabilities and selectivities for the following gas pairs: CO₂/N₂, CO₂/CH₄, O₂/N₂, ethylene/ethane, propylene/propane, 1-butene/butane, and 1,3-butadiene/butane. The analysis predicts a maximum CO₂-permeability for SILMs and an upper bound for permeability selectivity vs. CO₂-permeability with respect to the CO₂/N₂ and CO₂/CH₄ separations. Also summarized are the representative successes and failures for improving the separation performance of SILMs via functionalization and facilitated transport in the context of the CO₂/N₂, CO₂/CH₄, and olefin/paraffin separations. In the context of the CO₂-separations, the analysis recommends a number of future research foci including research into SILMs cast from RTILs with smaller molar volumes. In the context of olefin/paraffin separations, the preliminary data is encouraging when considering the use of facilitated transport via silver carriers. Since RTIL-solvent/solvent interactions dominate in terminating the overall SILM performance, past attempts at enhancing solute/solvent interactions via the addition of functional groups to the RTILs have not produced SILMs with better separation performance compared to the unfunctionalized RTILs. Future research into functionalized RTILs needs to consider the changes to the dominant solvent/solvent interactions and not just the solute/solvent interactions.     

Influence of chlorinated paraffin/titanium additives on burning and radiance performances of Magnesium/Teflon/Viton(MTV) foil-type composition

The influence of chlorinated paraffin/titanium (C₂₄H₂₉Cl₂₁/Ti) additives on burning and radiance performances of Magnesium/Teflon/Viton™ (MTV) foil-type was investigated via a high-speed camera, high-temperature differential thermobalance, far-infrared thermal imager and Fourier Transform Infrared (FTIR) remote-sensing spectrometer. We found that the burning temperature, radiance brightness, radiance area and radiance intensity after addition of C₂₄H₂₉Cl₂₁/Ti are improved by 124–196 °C (8–13%), 300–475 W·m⁻²·sr⁻¹ (12–19%), 943–1422 mm² (67–101%) and 3.17–4.99 W·sr⁻¹ (88–138%), respectively, and are maximized at the addition ratio of 10%. The substances formed by adding C₂₄H₂₉Cl₂₁/Ti could improve the middle and far infrared radiation.     

低温高活性熔铁催化剂上的超临界相费托合成反应

在固定床反应器中超临界相条件下研究了熔铁催化剂上的费托合成反应,发现在超临界介质中反应物和产物更容易扩散,较好地抑制了催化剂表面非活性碳的沉积,从而提高了费托合成反应中的CO转化率和烯烃选择性,增加了链增长因子,降低了甲烷选择性.同时,考察了超临界介质、反应温度、压力、H2/CO比和空速等条件对费托合成反应的影响.结果表明,C5-8正构烷烃在催化剂活性温度下都是适宜的超临界介质.当温度和压力都在介质的临界点以上时,介质表现出较好的传质与传热性能,可改善费托合成反应性能.     

Thermodynamic interpretation of three-parametric equation: Part II. The relative rate of reaction

The way of practical using of three-parametric equation transformed into linear relation between relative rate of decomposition and temperature was presented, basing on thermal decomposition of chemically defined and other compounds. Further possibilities of interpretation of that relation were presented. The meaning of slope (a ₂) was laid down, particularly with connection to thermodynamic considerations. This revised version was published online in July 2006 with corrections to the Cover Date.     

固体石蜡碳糊硅钼酸电极的研制及应用

将固体石蜡作粘合剂的碳糊电极在１０＾－４ｍｏｌ／Ｌ硅钼杂多酸溶液中活化后，其表面形成了杂多酸薄膜。电极对浓度为２．０×１０＾－５￣１．０×１０＾－２ｍｏｌ／Ｌ范围的硅钼杂多酸有所斯特响应；斜率为２９．０ｍＶ，从而可间接测定硅。该电极选择性、稳定性较好，响应快，已用于矿泉水样中偏硅酸含量测定。     

柴油对流动改进剂感受性差异的原因表征与分析

柴油对低温流动改进剂具有较高的选择性。流动改进剂对不同的炼油厂、不同原油以及不同的加工工艺炼制的柴油的感受性和降冷滤效果截然不同。主要是由柴油的化学组成决定。一般认为，柴油中正构烷烃的摩尔分数和分布是影响其低温流动改进剂使用效果的主要因素。正构烷烃摩尔分数越低，碳数分布越广，添加低温流动改进剂效果越好；此外，柴油中所含的单环芳烃是高碳数烷烃的优良溶剂，其摩尔分数越高，柴油低温蜡析出量越少，加低温流动改进剂效果越好。     

微胶囊化石蜡的制备和热性能

微胶囊化石蜡的制备和热性能;微胶囊;原位聚合法;相变材料;差示扫描量热法