NO emission characteristics in counterflow diffusion flame of blended fuel of H2/CO2/Ar

Flame structure and NO emission characteristics in counterflow diffusion flame of blended fuel of H₂/CO₂/Ar have been numerically simulated with detailed chemistry. The combination of H₂, CO₂ and Ar as fuel is selected to clearly display the contribution of hydrocarbon products to flame structure and NO emission characteristics due to the breakdown of CO₂. A radiative heat loss term is involved to correctly describe the flame dynamics especially at low strain rates. The detailed chemistry adopts the reaction mechanism of GRI 2.11, which consists of 49 species and 279 elementary reactions. All mechanisms including thermal, NO₂, N₂O and Fenimore are taken into account to separately evaluate the effects of CO₂ addition on NO emission characteristics. The increase of added CO₂ quantity causes flame temperature to fall since at high strain rates a diluent effect is prevailing and at low strain rates the breakdown of CO₂ produces relatively populous hydrocarbon products and thus the existence of hydrocarbon products inhibits chain branching. It is also found that the contribution of NO production by N₂O and NO₂ mechanisms are negligible and that thermal mechanism is concentrated on only the reaction zone. As strain rate and CO₂ quantity increase, NO production is remarkably augmented. Copyright © 2002 John Wiley & Sons, Ltd.     

Kinetics of droplet growth in liquid—liquid phase separation of polymer—diluent systems: experimental results

Liquid—liquid thermally induced phase separation of the polymer—diluent system isotactic poly(propylene)—diphenyl ether was studied under an optical microscope. It was found that as the system phase separated, droplets of a diluent-rich phase formed within a polymer-rich matrix. These droplets grew in size and decreased in number by a process known as coarsening. The scaling exponent relating droplet diameter and time was determined. The scaling exponent was found to be a strong function of the droplet phase volume fraction, and this strong dependence on volume fraction was relatively insensitive to temperature. The influence of the ratio of interfacial tension between the phases and the viscosity of the matrix phase was less significant on the growth rate of the droplets.     

环氧稀释剂十二烷基缩水甘油醚的合成

对稀释剂十二烷基缩水甘油醚的合成及影响产品质量的因素进行了研究,并以十二、十四混醇为原料进行了对比试验。     

Effect of reactive diluents on properties of unsaturated polyester/montmorillonite nanocomposites

Unsaturated polyester (UP)/montmorillonite (MMT) nanocomposite was prepared by using hydroxypropylacrylate (HPA) as a reactive diluent instead of conventional styrene monomer and the effect of polarity of reactive diluent on properties of nanocomposite was investigated. X‐ray and mechanical test data indicated that mixing for an extended period of time is essential to enhance the physical properties of nanocomposites in the UP/Cloisite 6A system. This was attributed to the high polarity of HPA that may disturb the preintercalation of UP resin into the galleries of MMT. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 238–242, 2004     

假紫罗兰酮环化工艺条件探讨

讨论了假紫罗兰酮酸化环合制备紫罗兰酮不同工艺条件对产品收率和组成的影响,结合有关文献重点探讨了作为维生素A工业合成原料的β-紫罗兰酮合成工艺条件的改进和优化,尤其是硫酸有机稀释剂(溶剂)的应用。     

The Effect of Organic Diluent on the Extraction of Eu(III) by HEH[EHP]

ABSTRACT

Because there are fewer tools available to probe the interactions therein, the effect of the fundamental chemistry of the organic diluent on solvent extraction equilibria has been under-characterized relative to the aqueous. As a result, diluents for solvent extraction are often selected for an application not for their utility as a medium for reaction, but for other (often equally) important reasons (like low flammability). To begin to improve this imbalance in the science, twenty different diluents have been used in a study of the extraction of radiotracer ^152/154Eu³⁺ from dilute nitric acid solutions using the extractant 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (HEH[EHP]). To increase the utility of the study and to honor the memory of Professor Jan Rydberg, this investigation was conducted by a cadre of comparatively inexperienced separation scientists (who are as a result no longer inexperienced separation scientists) as a radioanalytical chemistry and solvent extraction educational exercise. Slope analysis was used to determine the apparent stoichiometry of the extracted metal complex. The results discussed in the following indicate that, while the pH dependence exhibits the expected three H⁺ exchanged per metal ion extracted, the extractant dependence suggests that the number of protonated extractant molecules in the extracted complex changes with the organic diluent. The experimentally observed “extractant dependency” ranges from 2.5 to 3.0 dimer equivalent molecules per extracted metal ion. Ironically, in the diluents exhibiting the highest apparent M:(HA)₃ stoichiometry, HEH[EHP] extracts Eu³⁺ less efficiently. Europium luminescence spectroscopy was used to probe for changes in the first coordination sphere of the complex in different diluents. A model and conceptual framework for understanding these observations is described.     

SHS法制备AlN粉体的研究

以Al，N2为合成原料，AlN为稀释剂，4F为燃烧调节剂，NH采用SHSSelf-propagating High-temperature Synthesis）摘要以（法合成AlN粉体，实验系统地研究了稀释剂含量、燃烧调节剂含量、N2压力等因素对AlN合成率和粒径的影响。结果表明：在稀释剂AlN外加量为40%，燃烧调节剂NH4F外加量为5%，N2压力为8MPa条件下，AlN合成率为100%，粉体的平均粒径小于2μm。采用XRD、SEM、XDC等检测手段对粉体的物相组成和形貌进行表征，揭示了粉体性能与工艺因素之间的关系。     

复配型环氧树脂地层灌浆材料的研制

针对内蒙古某煤矿巷道岩石遇水粉化的实际问题，研制了一种新型的复配型环氧树脂作为地层灌浆材料，考察了固化剂、稀释剂、填料等对抗压强度的影响且进行了优化配比。结果表明，研制的灌浆材料抗压强度大于2MPa，固化时间在2h以内，固化后遇水强度有所增加，能较好地解决该矿岩石遇水粉化的突出问题。当酚醛胺与低分子聚酰胺比例为2：1时，固化效果较好；选用糠醛丙酮作稀释剂，当其用量大约为环氧树脂的l0％时，对凝固时间影响不大且可降低浆液的粘度，提高浆液的可灌性；当细砂、水泥、乳化环氧树脂的比例为1．5：1：1时抗压强度最大。     

Influence of a long‐side‐chain‐containing reactive diluent on the structure and mechanical properties of UV‐cured films

The dimethacrylate reactive diluent (HEMA‐DDSA), a long‐side‐chain‐containing reactive diluent, was prepared by reacting 2‐dodecen‐1‐ylsuccinic anhydride with two equivalents of hydroxyethyl methacrylate. Its structure was characterized by IR and ¹H NMR spectroscopy. This new diluent was added into the formulation of UV‐curable epoxy acrylate networks. Results show that the formulation with the addition of HEMA‐DDSA has massively reduced viscosity and shows several attractive properties of epoxy acrylate oligomers. The mechanical resistance of the films is dramatically enhanced with the incorporation of long alkyl groups derived from HEMA‐DDSA, the plastic deformation zone expands, thus decreasing the inner stress of the polymer structure. Moreover, the cured coatings have a higher glass transition temperature as the percentage of HEMA‐DDSA is increased up to 5 wt%. Due to the excellent integrated performance of the polymeric films, HEMA‐DDSA proved to be an effective reactive diluent, which is of potential interest for applications in high performance materials. © 2016 Society of Chemical Industry     

高压下H2/CO稀释剂对乙烷/空气层流扩散火焰中碳烟形成的影响

采用CoFlame程序模拟研究了高压下H₂/CO稀释剂对乙烷/空气层流扩散火焰中碳烟形成的影响。结果表明:H₂和CO添加之后,火焰温度均略有增加,且碳烟体积分数随着H₂/CO稀释比的增加而降低。H₂的添加使得碳烟表面生长区域的H自由基浓度增加,减少了初始碳烟颗粒成核及表面生长的活性位点数,导致脱氢加乙炔(HACA)反应中氢提取速率减缓以及碳烟颗粒表面生长速率减缓。CO的添加使得苯(A1)和芘(A4)摩尔分数减少,减缓了碳烟成核速率,导致碳烟的生成受到抑制。