摘要：A series of catalysts consisting of three‐dimensionally ordered macroporous(3DOM)x‐CeO2/Al2O3‐supported Au nanoparticles(x=2,10,20,and40wt%)were successfully synthesized using a reduction‐deposition *** catalysts were characterized using scanning electron microscopy,the Brunauer‐Emmett‐Teller method,X‐ray diffraction,transmission electron microscopy,ultraviolet‐visible spectroscopy,and temperature‐programmed reduction by *** nanoparticles of mean particle size5nm were well dispersed and supported on the inner walls of uniform ***3DOM structure improved the contact efficiency between soot and the *** Al‐Ce‐O solid solution was formed in the multilayer support,i.e.,x‐CeO2/Al2O3,by the incorporation of Al3+ions into the CeO2lattice,which resulted in the creation of extrinsic oxygen *** interactions between the metal(Au)and the support(Ce)increased the amount of active oxygen species,and this promoted soot *** catalytic performance in soot combustion was evaluated using a temperature‐programmed oxidation *** presence of CeO2nanolayers in the3DOM Au/x‐CeO2/Al2O3catalysts clearly improved the catalytic activities in soot *** the prepared catalysts,3DOM Au/20%CeO2/Al2O3showed high catalytic activity and stability in diesel soot oxidation.

摘要：Au/3DOM（three-dimensionally ordered macroporous） Al2O3 and Au/CeO2/3DOM Al2O3 were prepared using a reduction-deposition method and characterized using scanning electron microscopy,N2 adsorption-desorption,X-ray diffraction,transmission electron microscopy,ultraviolet-visible spectroscopy,temperature-programmed hydrogen reduction,and X-ray photoelectron *** nanoparticles of similar sizes were well dispersed and supported on the inner walls of uniform *** norminal Au loading is 2%.Al-Ce-O solid solution in CeO2/3DOM Al2O3 catalysts can be formed due to the incorporation of Al^3＋ ions into the ceria lattice,which causes the creation of extrinsic oxygen *** extrinsic oxygen vacancies improved the oxygen-transport *** strong metal-support interactions between Au and CeO2 increased the amount of active oxygen on the Au nanoparticle surfaces,and this promoted soot *** activities of the Au-based catalysts were higher than those of the supports（Al2O3 or CeO2/3DOM Al2O3） at low ***/CeO2/3DOM Al2O3 had the highest catalytic activity for soot combustion,with T（10）,T（50）,and T（90） values of 273,364,and 412℃,respectively.

摘要：A series of K-doped Mn0.5Ce0.5Oδ （K-MCO） catalysts with three-dimensionally ordered macroporous （3DOM） structure and different K loadings were successfully synthesized using simple methods. These catalysts exhibited well-defined 3DOM nanostructure, which consisted of extensive interconnecting networks of spherical voids. The effects of the calcination temperature and calcination time on the morphological characteristics and crystalline forms of the catalysts were systematically studied. The catalysts showed high catalytic activity for the combustion of soot. 3DOM 20% K-MCO-4h catalyst, in particular, showed the highest catalytic activity of all of the catalysts studied （e.g., Ts0 = 331 ~C and Smco2 = 95.3%）. The occurrence of structural and synergistic effects among the K, Mn, and Ce atoms in the catalysts was favorable for enhancing their catalytic activity towards the combustion of diesel soot. Furthermore, the temperatures required for the complete combustion of the soot （〈400 ℃） were well within the exhaust temperature range （175-400 ℃）, which means that the accumulated soot can be removed under the conditions of the diesel exhaust gas. These catalysts could therefore be used in numerous practical applications because they are easy to synthesize, exhibit high catalytic activity, and can be made from low cost materials.

摘要：采用感官分析方法—时间-强度法(time intensity,TI)和定量描述分析法(quantitative descriptive analysis,QDA),结合HPLC,对8种不同产区的花椒油的麻感特征及麻味物质进行了测定。TI结果展示了花椒油的时间动态特性,ZAO1样品具备最高的麻感强度(intensity of maximum,I_(max))和曲线下面积(area under the curve,AUC)。I_(max)与AUC之间呈现出较好的正相关性。QDA结果揭示了不同产区花椒油的麻感属性差异,其中麻木感、振动感、垂涎感在ZAO1样品中表现突出,而在ZBO4样品中表现最弱;灼热感在ZAO2样品中表达最为强烈。HPLC测定结果显示,不同产区的花椒油的麻味物质组成及含量存在显著性差异。进一步偏最小二乘回归(partial least squares regression,PLSR)分析表明,羟基-α-山椒素(hydroxy-α-sanshool,HαSS)是影响麻木感、振动感和垂涎感的关键物质。此外,麻木感、振动感和垂涎感之间呈现出较好的正相关性。该结果初步揭示了花椒油中麻感特征差异及其与麻味物质的关联性,为我国花椒油的品质监控提供实验数据和理论基础。

摘要：硅铝基材料因其孔道结构多样、孔径大小易调、比表面积较大、易于通过负载活性金属及嫁接有机官能团等特点,具有调变反应活性及选择性等优势,广泛用作各种工艺过程的催化剂材料。其中,具有较大孔径的有序孔材料对催化反应活性中心位点的分布和反应物、中间物及产物的传质扩散有着重要的影响。本文综述了近年来有序孔材料合成中不同扩孔剂的添加对其孔道结构及物化性质的影响,从化学扩孔,如微孔材料的酸碱后处理;物理扩孔,如在介孔材料合成中添加极性与非极性扩孔剂等方法入手,总结了扩孔剂的作用机理及其对材料性质影响,并对未来利用扩孔剂合成有序孔材料进行了展望,为特种催化剂材料后续的设计及优化改性等提供了信息及方向。

摘要：目的：研究碱性磷酸酶（alkaline phosphatase, ALP）试剂开瓶后的稳定性，为实验室合理购买试剂包规格提供依据。方法：采用同步测量设计方案，首先选择5个试剂盒，分别记为S0、S1、S2、S3、S4，第1天上午8点启用试剂S4进行ALP常规检测，未用完试剂盖紧盖，置2-8℃保存备用；第2天、第3天、第4天上午相同时间、相同方式启用S3、S2、S1；第5天启用试剂S0；在仪器上按试剂说明书设置5个相同参数的ALP检测通道，记为ALP0、ALP1、ALP2、ALP3、ALP4，对应试剂为S0、S1、S2、S3、S4；在荷兰威图Selectra-E全自动生化仪上用校准品（中生北控生物科技有限公司）校准各个通道；测量样品并进行结果比较分析。结果：试剂 S3、S4与试剂 S0测量样品结果比较差异有统计学意义（P〈0.01），试剂S1、S2与试剂S0测量样品结果比较差异无统计学意义（P〉0.05）。结论：ALP试剂开瓶后48 h内是稳定的，实验室应根据用量选择合适包装规格的试剂包。

摘要：环境保护意识的大幅度提升促使车用燃料质量标准日益严格,为实现汽油和柴油中硫含量不断降低的目标,迫切需要研发超深度脱硫技术。目前加氢脱硫技术是大规模工业化应用的关键技术,其核心是高效催化剂的研制。介绍了FCC汽油及柴油中所含各类硫化物的加氢脱硫反应路径,主要讨论了其中难以脱除的噻吩类、苯并噻吩类、二苯并噻吩类和4,6-二甲基二苯并噻吩类硫化物在各类催化剂上的反应机理,为超低硫清洁油品加氢脱硫催化剂的设计提供理论指导。

摘要：重质油分子结构复杂、尺寸较大且容易聚集形成缔合体,致使在加氢及催化裂化催化剂孔道内存在明显的扩散阻力,显著阻碍了反应物分子与催化剂孔道内部活性位的接触,导致反应速率与转化率明显低于轻质原料。因此,研究重油分子在催化剂孔道内扩散受阻情况可以为催化剂的设计优化提供信息与指导。尽管借助仪器或膜材料能获得溶质分子的扩散性能,但与反应条件下扩散规律差别较大,因此在实际反应体系下获得重油分子在催化剂孔道中的扩散传质具有重要的现实意义。综述采用反应动力学手段获得扩散传质数据并建立受限因子关联模型及其影响因素的研究进展,从反应物选择、反应条件及催化剂等因素的优化角度对重油分子受阻扩散研究进行展望。

摘要：针对无人直升机航迹控制要求,提出一种基于线性变参数(LPV)控制理论的无人直升机一体化式飞行控制律设计方法,通过速度、侧滑角、高度和偏航角控制通道的显模型跟踪控制,实现无人直升机航迹控制。建立了无人直升机高阶非线性动力学模型,模型中考虑了旋翼桨叶挥舞和摆振运动、旋翼动态入流、机体运动之间的运动耦合,用于检验直升机高阶运动特性对控制律性能和闭环系统稳定性的影响。由于无人直升机的非线性动力学模型是典型的周期性系统,基于简谐平衡方法进行无人直升机的配平和模型线性化计算,在速度包线内得到用于控制律设计的无人直升机LPV模型,通过凸函数优化方法求解LPV控制律的参数。基于典型直升机机动,采用数值仿真方法对LPV控制律在传感器噪声影响下的控制性能进行检验,仿真结果表明:LPV控制律在速度包线内具有良好的控制性能和鲁棒性,无人直升机闭环系统在机动飞行中满足给定的性能要求。

摘要：通过建立三维地基与路基模型,对交通荷载作用下风积沙换填地基与风积沙低路基动力响应进行了数值计算,分析了竖向位移、应力沿深度变化的规律以及动力响应的滞后效应,得到了动力时程曲线,确定了路基动力响应影响深度约为1.9 m。