Renewable hydrogen production from steam reforming of glycerol (SRG) over ceria-modified γ-alumina supported Ni catalyst

Excess crude glycerol derived as a by-product from biodiesel industry prompts the need to valorise glycerol to value-added chemicals. In this context, catalytic steam reforming of glycerol (SRG) was proposed as a promising and sustainable alternative for producing renewable hydrogen (H₂). Herein, the development of nickel (Ni) supported on ceria-modified mesoporous γ-alumina (γ-Al₂O₃) catalysts and their applications in catalytic SRG (at 550–750 °C, atmospheric pressure and weight hourly space velocity, WHSV, of 44,122 ml·g⁻¹·h⁻¹ (STP)) is presented. Properties of the developed catalysts were characterised using many techniques. The findings show that ceria modification improved Ni dispersion on γ-Al₂O₃ catalyst support with highly active small Ni particles, which led to a remarkable catalytic performance with the total glycerol conversion (ca. 99%), glycerol conversion into gaseous products (ca. 77%) and H₂ yield (ca. 62%). The formation rate for H₂ production (14.4 × 10⁻⁵ mol·s⁻¹·g⁻¹, TOF (H₂) = 3412 s⁻¹) was significantly improved with the Ni@12Ce-Al₂O₃ catalyst, representing nearly a 2-fold increase compared with that of the conventional Ni@Al₂O₃ catalyst. In addition, the developed catalyst also exhibited comparatively high stability (for 12 h) and coke resistance ability.     

硼中子俘获治疗加速器ECR质子源电磁场仿真设计

电子回旋共振(ECR)质子源具有可给流强高、亮度高、可靠性高、使用频率高、易维护、小型化等优点,因而被硼中子俘获治疗(BNCT)装置的直线加速器所采用。本文利用CST软件对2.45 GHz ECR质子源进行优化设计。优化后ECR质子源的等离子体发生器腔体的尺寸为101.12 mm×45.00 mm,给出了脊波导耦合器的最优尺寸参数,使等离子体发生器腔体内电场强度提高为普通波导的4.5倍。通过Opera-3D对ECR质子源的引出电极结构进行了仿真计算,并给出了优化参数。另外,初步设计了质子源的线圈磁铁系统,优化了磁场分布。本文结果为质子源的研制提供了数据。     

CPAM的分子质量和电荷密度对热磨机械浆中DCS絮聚的影响

研究了热磨机械浆中,不同分子质量、不同电荷密度的阳离子聚丙烯酰胺（CPAM）对溶解和胶体物质（DCS）的影响。阴离子物质DCS来源于机械浆,能与阳离子聚合物反应。实验结果表明,相对分子质量为900万、电荷密度为3.2mmol/g的CPAM能与抽出物发生最有效的絮聚,CPAM对抽出物中的甘油三酯和甾基酯的作用效果最大,并且随着CPAM的添加,水样中负电荷密度减小。这些结果与添加CPAM后抽出物浓度减小密切相关。     

发芽糙米乳酸菌饮料的研制

以发芽糙米和鲜牛奶为主原料,经乳酸发酵后、调配成乳酸菌饮料。通过试验确定发芽糙米酶解最佳条件:即酶的添加量为7μg/g,酶解时间为50min,酶解温度为90℃。混合液最佳发酵条件为:发芽糙米浆∶牛奶为1∶2,接种量为6%,发酵温度45℃,发酵时间4.5h。选用复合稳定剂进行试验:即0.2%羧甲基纤维素钠(CMC-Na)和0.3%海藻酸丙二醇酯(PGA)。发芽糙米乳酸菌饮料的最佳条件为:发芽糙米混合发酵乳用量为50%,白砂糖为11%,柠檬酸为0.4%,感官评分为89分,γ-氨基丁酸含量为1.57mg/(100ml)。     

Leriche综合征血管腔内治疗效果分析

【摘要】 目的 评价血管腔内治疗Leriche综合征的效果。方法 收集2010年9月至2014年10月收治的57例Leriche综合征患者临床资料,对经皮腔内血管成形术（PTA）治疗结果进行分析。结果 57例患者（65条患肢）中接受单纯PTA术2例,导管接触溶栓（CDT）后PTA结合支架植入5例,PTA结合支架植入50例,共植入支架97枚,技术成功率100%。踝-肱指数（ABI）由术前平均0.42±0.22改善至术后平均0.83±0.15,差异有显著统计学意义（P＜0.01）。平均随访（9.8±2.8）个月,6、12个月一期通畅率分别为95.4％、90.7％,二期通畅率为96.4%。所有患者术后下肢缺血症状均得到改善。围手术期发生髂动脉球囊扩张破裂2例,肱动脉穿刺点假性动脉瘤1例,穿刺点血肿3例,脑梗死2例,心肌梗死1例。对比剂肾病1例,最终并发多脏器功能障碍综合征死亡,围手术期死亡率1.75%。1例二期处理后3个月出现支架内再闭塞,予人工血管旁路移植术。结论 PTA术治疗Leriche综合征安全可靠,并发症少,围手术期死亡率低,近期通畅率可。

     

纯生物质纤维素气凝胶的制备及其阻燃性能

为有效推进纺织领域资源循环利用、增强绿色低碳循环发展,以废棉纱为原料制备再生纤维素气凝胶,并在水相环境驱动下,将浸提自废弃农林作物的生物质茶多酚沉积于该气凝胶表面,开发纯生物质节能保温用阻燃纤维素气凝胶(BTCA),并分别采用极限氧指数仪、热重分析、热重红外联用仪、拉曼光谱等分析了BTCA的热稳定性、热分解气固相产物及...     

Liquid‐phase catalytic thermal cleavage of thiocarbonylthio end‐groups for polymers synthesized by RAFT polymerization: Influences of different solvents

Catalytic thermal cleavage of thiocarbonylthio end‐groups for RAFT synthesized polymers is usually accompanied by other side reactions such as chain‐scission and crosslinking. Occurrence of these side reactions depends on polymers, end‐groups, and oxidation–reduction property of reaction media in a liquid phase. Herein, well‐defined hydrophilic poly(4‐vinylpridine) (P4VP) and hydrophobic polystyrene (PS) are synthesized via a controlled RAFT polymerization in the presence of S‐1‐Dodecyl‐S′‐(R,R′‐dimethyl‐R″‐acetic acid) trithiocarbonates (DDMAT). Then their thiocarbonylthio end‐groups are cleaved through catalytic thermolysis in a liquid phase. Under the catalysis of Cu(0), all S‐containing groups can be removed at 165 °C in 3 h. To study the effect of solvent on thermolysis and microstructure of polymer, nitrobenzene of oxidation property and diethylene glycol of reduction property are chosen as solvents. Because of oxidizing property of nitrobenzene, Z groups of RAFT agent are eliminated at the same time that thiocarbonylthio end‐groups are removed. Therefore crosslinking among multipolymer chains occurs. While diethylene glycol is used as a solvent, no crosslinking occurs. Diethylene glycol is superior to nitrobenzene for synthesis of well‐defined polymer without S‐containing groups. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43992.     

节能减排背景下的机组组合模型和算法研究

在节能减排背景下对机组组合目标函数进行了调整,采用排放价格因子将系统总能耗最小和总排放最小的多目标问题转化为单目标问题,利于全网开展机组组合和经济调度.将多时段的机组组合问题在时间上解耦,转化为单小时的子问题,并采用基于内点法的混合整数规划法求解子问题.通过两个算例验证了算法和模型的有效性.     

煤粉料仓通气下料流动行为

在可视化有机玻璃料仓系统上对煤粉下料过程及其特性进行了实验研究。研究表明,煤粉介质粒径小、比表面积大,属于黏附性非自由流动粉体,下料流动困难;料仓通气技术可以显著改善煤粉流动性从而促进料仓下料,但过量通气反而会抑制煤粉下料。通过分析下料过程中料仓壁面的压力信号,揭示了料仓压力分布特性,分析了超侧压现象并定义了压力转换面。实验发现,通气可以在一定程度内减小超侧压幅度,扩大煤粉流化疏松区域,提升转换面高度。此外,研究还发现通气下料过程中存在气体穿透现象,穿透临界高度随通气量的增加而提高,并且穿透后煤粉下料流率降低。     

聚砜、复合增韧剂改性酚醛模塑料的耐油性研究

通过采用聚砜、复合增韧剂对酚醛模塑料的界面进行改性，成功地制得了一种耐油型酚醛模塑料。分别在200℃和170℃的滑油中浸24h和100h，测其力学性能和电绝缘性能，除垂直纤维方向的压缩强度外，各项性能保持率均达95％以上。采用SEM等手段对改性模塑料进行研究和分析，并同国外同类材料进行比较分析，发现聚砜、复合增韧剂改性酚醛模塑料具有优异的力学性能、电绝缘性能和耐滑油性能，是国防用理想材料。