Hydrogen production by glycerol steam reforming with in situ hydrogen separation: A thermodynamic investigation

Thermodynamic features of hydrogen production by glycerol steam reforming with in situ hydrogen extraction have been studied with the method of Gibbs free energy minimization. The effects of pressure (1–5 atm), temperature (600–1000 K), water to glycerol ratio (WGR, 3–12) and fraction of H₂ removal (f, 0–1) on the reforming reactions and carbon formation were investigated. The results suggest separation of hydrogen in situ can substantially enhance hydrogen production from glycerol steam reforming, as 7 mol (stoichiometric value) of hydrogen can be obtained even at 600 K due to the hydrogen extraction. It is demonstrated that atmospheric pressure and a WGR of 9 are suitable for hydrogen production and the optimum temperature for glycerol steam reforming with in situ hydrogen removal is between 825 and 875 K, 100 K lower than that achieved typically without hydrogen separation. Furthermore, the detrimental influence of increasing pressure in terms of hydrogen production becomes marginal above 800 K with a high fraction of H₂ removal (i.e., f = 0.99). High temperature and WGR are favorable to inhibit carbon production.     

滋味物质间相互作用的研究进展

人类的味觉提供了有关食品质量及其组成的必要信息。人类可鉴别出食物的5 种基本味觉,即甜、咸、酸、苦和鲜味,但食物是多种滋味化合物组成的混合体系,因此滋味物质间相互作用是不可避免的。滋味物质间的相互作用发生在3 个层面,即化合物混合时的化学反应、一种物质对另一种物质滋味受体的影响、混合物质在大脑中的综合感知。其中研究较多的是滋味物质在第二层面上的相互作用。二元、三元及多元滋味物质之间的关系是复杂的：当滋味化合物低强度/浓度混合时呈现增强效应;中等强度/浓度往往呈现加和作用;高强度/浓度混合时常呈现抑制作用。另外,滋味感知受很多因素的影响,如温度、pH值、黏度、硬度、受试者生理状况等。滋味物质间相互作用的研究主要聚焦在饮料滋味改良、药品苦味掩盖和口腔护理产品开发等具有广阔研究前景。     

Secondary organic aerosol formation from the photooxidation of p- and o-xylene

The formation of secondary organic aerosol (SOA) from the photooxidation of xylene isomers (m-, p-, and o-xylenes) has been extensively investigated. The dependence of SOA aerosol formation on the structure of xylene isomers in the presence of NO was confirmed. Generally, SOA formation of p-xylene was less than that of m- and o-xylenes. This discrepancy varies significantly with initial NOx levels. In a NOx-free environment, the difference of aerosol formation between o- and p-xylenes becomes insignificant. Several chemical pathways for the SOA dependence on structure and NOx are explored, with the experimental findings indicating that organic peroxides may be a major key to explaining SOA formation from aromatic hydrocarbons.     

CT引导下 １２５ I放射性粒子植入治疗肝癌门静脉癌栓的疗效评价

目的探讨CT引导下 １２５ I放射性粒子植入联合肝动脉化疗栓塞术（TACE）治疗肝癌合并门静脉癌栓（PVTT）的疗效。方法回顾性分析原发性肝癌合并PVTT患者５８例,A组（２６例）行TACE结合CT引导下 １２５ I放射性粒子植入局部放射治疗;B组（３２例）单纯行TACE。对比两组疗效。结果A组１、２年生存率分别为４２．３％、２３．０％,平均生存期１５．５个月,完全缓解（CR）３例,部分缓解（PR）９例,总有效率（CR＋PR）为４６．２％（１２／２６）。B组１、２年生存率分别为２１．９％、６．３％,平均生存期７．５个月CR２例,PR６例,CR＋PR为２５．０％（８／３２）。A组的生存率及总有效率显著高于B组（P＜０．０５）。结论TACE联合CT引导下 １２５ I放射性粒子植入治疗肝癌门脉癌栓能明显提高其疗效,并具有创伤少,并发症少等优点。     

薄煤层采煤机摇臂减速器的可靠性研究

以薄煤层采煤机摇臂减速器为例,进行了基于ANSYS/PDS模块的三维动态齿轮齿根弯曲强度可靠性分析。研究了在不同工况下,齿根应力、安全系数和可靠性三者之间的关系。通过与MATLAB数值计算结果对比,验证了有限元法求解可靠度的准确性。通过对齿轮灵敏度的分析,确定了影响齿轮可靠度的主要因素,为进一步对齿轮优化设计提供参考。     

环82 区长8 酸敏储层前置酸压裂技术研究与应用

随着油田滚动勘探开发的不断深入,长庆陇东油田长8储层部分区块物性变差,采用常规加砂压裂工艺,单井产量偏低,需要探索新的工艺以提高单井产量。针对长庆陇东油田长8储层特点,室内开发了一套适应于长8酸敏储层的前置酸酸液体系,与目前体系比较,改进后前置酸酸液体系对研究区岩屑溶蚀率提高了35.4%,对胍胶压裂液的破胶液黏度降低了42.1%,岩心伤害率降低了67.9%,体现了较好的储层适应性。通过PT软件模拟提出了前置酸压裂工艺中的前置酸酸液用量强度、施工排量、关井时间。经现场32口井试验,长8酸敏储层前置酸压裂改造技术在环82区试油日产油量提高了20.4%,取得了较好的增产效果。     

CO2 recovery from flue gas by PSA process using activated carbon

An experimental study was performed for the recovery of CO₂ from flue gas of the electric power plant by pressure swing adsorption process. Activated carbon was used as an adsorbent. The equilibrium adsorption isotherms of pure component and breakthrough curves of their mixture (CO₂ : N₂ : O₂=17 : 79 : 4 vol%) were measured. Pressure equalization step and product purge step were added to basic 4-step PSA for the recovery of strong adsorbates. Through investigation of the effects of each step and total feed rate, highly concentrated CO₂ could be obtained by increasing the adsorption time, product purge time, and evacuation time simultaneously with full pressure-equalization. Based on the basic results, the 3-bed, 8-step PSA cycle with the pressure equalization and product purge step was organized. Maximum product purity of CO₂ was 99.8% and recovery was 34%.     

高温蒸煮法与微波法处理玉米芯制备低聚木糖比较

通过对高温蒸煮法和微波法处理玉米芯制备低聚木糖的比较，碍出：高温蒸煮法产物复杂，玉米芯经稀酸浸泡后再高温蒸煮，木聚糖提取率和水解液中还原糖含量均较高，但产物主要是单糖；微波法产物较单一，玉米芯经稀碱液浸泡后再微波处理，木聚糖提取率和水解液中还原糖含量均高，且其主要成分是木二糖，糠醛含量少。比较2种预处理方法，微波处理玉米芯制备低聚木糖更理想。     

正丁基硫醇-正辛烷体系等压气液相平衡研究

利用双循环气液平衡釜测定了101.3 kPa下正丁基硫醇-正辛烷体系的气液平衡数据,并运用该实验结果,进一步获得组分的液相活度系数。实验数据经Herrington方法检验符合热力学一致性。用UNIQUAC热力学模型对该实验数据进行处理,计算结果与实验值的平均绝对偏差为0.050 5。