Study on Bimetallic Active Center Catalysts and Kinetics of Ruthenium Catalysts for Ammonia Synthesis

合成氨工业是最重要的化学工业之一，世界各国都致力于合成氨工业的发展。钌催化剂由于其高的催化活性及温和的反应条件被誉为“第二代氨合成催化剂”。1992年，以活性碳为载体的钌催化剂在加拿大Ocelot合成氨厂首次实现工业化。但是，在氨合成反应条件下，钌金属容易使活性碳载体发生甲烷化，导致催化剂活性的降低，限制了钌催化剂的大规模工业应用。氧化镁载体是碱性氧化物，且具有很高的比表面积及稳定性。因此，也作为钌基氨合成催化剂的载体受到广泛研究，但是氧化镁负载的钌催化剂的氨合成活性远低于活性碳负载的钌催化剂。因此，制备具有高氨合成活性及稳定性的钌催化剂是合成氨工业的研究重点。但由于钌催化剂成本昂贵、碳载体易...Ammonia synthesis is one of the most important chemical industries in the world, every countries have paid great efforts to develop ammonia synthesis industry. Ruthenium-based catalyst has been named as "The second-generation catalyst for ammonia synthesis", because it has high catalytic activity for ammonia synthesis and can be operated in mild conditions. In 1992, carbon supported ruthenium cata...学位：理学硕士院系专业：化学化工学院化学系_物理化学(含化学物理)学号：20032510

The Development of a High Resolution ESI-QTOFMS Coupled with Three Sect Quadrupoles

报道了实验室研制的电喷雾离子源 ,具有射频四极杆接口的高分辨飞行时间质谱 (ESI- QQQ- TOFMS)仪器。该仪器具有以下特点 :在离子调制区使用三组四极杆 ,有效地减少离子束的空间分散和能量分散 ;采用正负双脉冲推斥和离子垂直引入方式 ;经过优化设计的二级有网反射器 ;新颖的 MCP安装方法。经初步调试 ,该仪器的分辨本领已优于 1 0 ,0 0 0 ,质量测定精度优于 1 0× 1 0 - 6 。该仪器于 2 0 0 2年 6月通过了国家教育部科技成果鉴定 [鉴字 [教 2 0 0 2 ]第 0 0 8号 ],其主要性能指标已经达到了国际先进水平An high resolution ESI QQQ TOFMS coupled with three sect quadrupoles is reported.The home made instrument in the laboratory has a number of features. It can be used as tandem MS (MS/MS) owing to three sect quadrupoles used in the ion modulation part; the TOFMS analyzer adopted positive negative double extrusion pulse and orthogonal injection way; two grade ion reflector with grids designed by computer simulation, and new micro channel plate (MCP) mounting method. This instrument has already been in working condition after preliminary adjustment, and the resolution over 10,000 was achieved.国家自然科学基金资助项目 (专项 H-2 992 70 0 2和重点 2 92 45 110 ) ;; 教育部现代分析科学重点实验室开放课

Drag reduction using riblets downstream of a high Reynolds number inclined forward step flow

Micro-riblet is an efficient passive method for controlling turbulent boundary layers, with the potential to reduce frictional drag. In various applications within the transportation industry, flow separation is a prevalent flow phenomenon. However, the precise drag reduction performance of riblets in the presence of flow separation remains unclear. To address this, an inclined forward step model is proposed to investigate the interaction between riblet and upstream flow separation. The large eddy simulation (LES) method is applied to simulate the flow over geometries with different step angles and riblet positions. The results show riblets still reduce wall frictional resistance when subjected to the upstream flow separation. Remarkably, as the angle of the step increases from 0 degrees to 30 degrees, the drag reduction experiences an increment from 9.5% to 12.6%. From a turbulence statistics standpoint, riblets act to suppress the Reynold stress in the near-wall region and dampen ejection motions, thus weakening momentum exchange. Quadrant analysis reveals that with the augmentation of flow separation, the Q2 motion within the flow field intensifies, subsequently enhancing the riblet-induced drag reduction. Moreover, the position of the rib lets has a significant impact on the pressure drag. Riblets close to the point of separation enhance flow separation, altering the surface pressure distribution and thus increasing the resistance. The results reveal that when the riblets are positioned approximately 160 riblet heights away from the step, their effect on the upstream flow separation becomes negligible. The precise performance of riblets under complex flow conditions is important for their practical engineering application

1978～2008年中国湿地类型变化

分别基于美国陆地卫星(Landsat MSS/TM/ETM+)和中巴资源卫星(CBERS-02B)影像数据,以人工目视解译为主,完成了中国1978～2008年4期(基准年分别为1978,1990,2000和2008年)湿地遥感制图,并进行了大量的室内外验证.在此基础上,对我国湿地现状及近30年来湿地变化进行了初步分析,得到以下主要结论:(ⅰ)截止2008年,中国湿地面积约为324097km2,其中以内陆沼泽(35%)和湖泊湿地(26%)为主.(ⅱ)1978～2008年,中国湿地面积减少了约33%,而人工湿地增加了约122%.过去30年里湿地减少的速度大幅降低,由最初5523km2/a(1978～1990年)降为831km2/a(2000～2008年).(ⅲ)减少的自然湿地(包括滨海湿地和内陆湿地),其类型变化由湿地向非湿地转化的比例逐渐降低.初期(1978～1990年)几乎全部(98%)转换为非湿地;在1990～2000年间减少的自然湿地约有86%转化为非湿地,而在2000～2008年,这一比例下降为77%.(ⅳ)气候变化和农业活动是中国湿地变化的主要驱动因素,湿地变化在中国分为三大不同特征区域,即西部三省/自治区(西藏、新疆和青海)、北部两省/自治区(黑龙江和内蒙古)和其他省市区.其中西部区域尤其是青藏高原,湿地变化的驱动因子以气候增温为主;新疆湿地由于气候增温和农业活动共同作用造成变化不大.北部省/自治区的湿地变化则主要由农业活动引起;而其他省市区的湿地变化几乎完全受控于人类的农业经济活动

Study of New Kubicek Model for Cardiac Stroke Volum

针对传统的Kubicek模型在心脏每搏输出量(SV)理论推导和实际测量中存在一定的缺陷,根据心脏血流动力学原理,提出了一种新型Kubicek模型及其阻抗和导纳等效电路图,并依据该新型模型推导出基于阻抗法和导纳法测量SV的计算公式,指出依据旧模型进行的阻抗法测量产生偏差的重要原因是忽略了血液电导率(ρ)的变化.通过对新模型中两种测量方法的比较,进一步从理论上验证了导纳法具有更高测量精度.这些结论对今后的应用研究及相关仪器的开发具有一定的参考价值.Using the old Kubicek model to deduct the formulas of cardiac stroke volume(SV) and to measure the parameter,we found that there were some disadvantages.Based on the theory of heart hemodynamics,a new kind of Kubicek model and its equivalent circuit diagrams of impedance and admittance were proposed in this paper.Using the new model,the formulas of cardiac stroke volume(SV) based on the methods of impedance and admittance were worked out.The paper showed that the important cause of the measurement error of impedance method,which was based on the old Kubicek model,was in neglecting the change of the conductance(ρ) of blood.Furthermore,we validated that,compared to the method of impedance in theory,the method of admittance had higher accuracy for measuring the cardiac stroke volume(SV).These conclusions have reference value for the future research and exploitation of relative instrument.福建省教育厅科研基金(JB06160)资

Supported Catalysts with Ru-M (M=Fe,Co,Ni,Mo) Bimetallic Active Centers for Ammonia Synthesis

[中文摘要]研究了钾促进的双金属中心Ru-M(M=Fe,Co,Ni,Mo)氨合成催化剂.结果表明,Ru-Co催化剂活性最高,Ru和Co含量均为2%的Ru-Co催化剂具有最好的应用价值,其催化活性与Ru和Co含量均为4%的催化剂相近.此外,还对以镁铝尖晶石、氧化镁和镁铝复合氧化物等不同氧化物为载体的Ru-Co双金属中心催化剂进行了对比研究.结果表明,以高温煅烧制得的氧化镁作载体的催化剂活性最高.[英文摘要]Supported Ru-M (M=Fe, Co, Ni, Mo) bimetallic active center catalysts with a potassium promoter for the ammonia synthesis were studied. The results show that the activity of the Ru-Co catalyst is the highest, and the activity of Ru-Mo is the lowest. When the Ru loading decreases by half (from 4% to 2%), the Ru-Co catalyst with a Co loading of 2% is the most valuable and exhibits an activity almost the same as the catalyst with 4%Ru and 4%Co. The Ru-Co catalysts with Ru and Co loadings of 2% supported on Mg-Al complex oxide,MgAl2O4 spinel, and MgO were also studied, and the catalyst supportedon MgO calcined at 600 ℃ has the highest activity.国家自然科学基金(20273053,20023001和29933040)；国家重点基础研究发展计划(973计划)(001CB108906)；福建省自然科学基金(E0310001)资助项目

树轮记录的吕梁山北部过去175年来帕尔默干旱指数变化

利用采自吕梁山北部地区的油松样本,建立了过去175年来的树轮宽度年表。相关分析表明:标准年表(STD)与当年5— 6月的帕尔默干旱指数(Palmer drought severity index,PDSI)相关性最好,相关系数为0.687(n= 50,p<0.001)。因此,采用树轮宽度标准年表(STD)序列重建了1829— 2003年5— 6月的PDSI序列,重建方程的方差解释量达到47.16%。重建序列发现9个偏湿时段,分别为1833— 1836年、1845— 1851年、1857— 1863年、1869— 1874年、1882— 1887年、1896— 1899年、 1932— 1939年、1949— 1965年、1975— 1985年;10个偏干时段,分别为1829— 1832年、1837— 1844年、1852— 1856年、1864— 1868年、1875— 1881年、1888— 1895年、1900— 1931年、1940— 1948年、 1966— 1974年、1986— 2003年。同时发现20世纪20年代的严重干旱事件以及20世纪末气候干旱化加重的趋势。空间相关结果显示:重建的PDSI代表了周边大范围的干旱变化,同时,与基于历史文献的干湿指数(DWI)显著相关(p<0.002),说明无论是空间还是时间尺度上,重建结果都可以代表吕梁山周边大范围的干旱变化。此外,重建序列与不同定义的东亚夏季风指数都显著相关(p<0.02),说明东亚夏季风对研究区的干湿变化具有调制作用。多窗谱分析表明重建序列存在2— 7年、12年、13.6年、 19.2年、21.6年、26.1年的周期变化,这些周期变化可能与ENSO、太阳活动有关

Studies on preparation and property of Ru-based ammonia synthesis catalyst supported on mixed oxide

[英文文摘]The Mg,Al,Alkaline-earth mixed oxides were synthesized by co-precipitation of two mixed solutions and then loaded with Ru to get the Ru-based catalyst.X-ray diffraction,CO_2-adsorption,N_2 physical-adsorption and SEM were introduced to characterize the phase,basicity,area,and configuration of the surface of the mixed oxide.The ammonia synthesis experiment was carried out under the fluxin of 3H_2/1N_2,with the velocity 2100 mL/h and pressure 0.2 MPa.The activity test shows that the catalyst supported on mixed oxide has farmore betteractivity than those supported on single oxide. It can be concluded from the resultof the characterization and activity test that the activityof the catalystwasmainly affected by the basicityof the surface rather than the surface areas.国家自然科学基金资助项目(20273053,20023001和29933040)；973项目(001CB108906)；福建省自然科学基金资助项目(E0310001)

两例先天性无痛症患者的心理生理特点研究 Ⅰ.情绪特点

本工作研究两例先天性无痛症患者的心理特点,主要是其情绪特点,以探讨疼痛和情绪的关系,并借以检验疼痛学说的意义。例一,女,10岁,智力略低于正常,艾森克少年儿童人格问卷表评定人格正常。与身体损伤有关的恐惧感明显缺乏,但与社会和教育影响有联系的恐惧感却甚于正常儿童。情绪急躁,易发作暴发性脾气而不能控制。在突然刺激(强光、强铃声)下的反应和正常儿童相近。例二,男,13岁,智力明显落后,人格评定正常,各种恐惧感均明显缺乏。情绪经常呈明显欣快状态。突然刺激下有口语惊吓和动作反应但无相应的面部表情和植物性神经系统的变化。两例均有无目的的多动作表现。看来疼痛和情绪有某种关系,但本结果并不能证实疼痛的情绪学说。</p

两例先天性无痛症患者的心理生理特点研究 Ⅱ.对致痛性强刺激的知觉和反应

本工作对两例先天性无痛症患者对于致痛性强刺激的知觉和反应进行了研究(例1女,10岁,例2男,13岁)。对照组为20例正常儿童,性别和年龄均与患儿相匹配。 结果:1),生活中痛:两例患儿均无(包括痛感觉和痛反应)。2)实验性痛:①痛感觉:两例患儿均无; ②&ldquo;痛&rdquo;反应:例1有&ldquo;痛&rdquo;反应(脉搏和呼吸的变化以及行为反应明显,大致与正常儿童相似)。例2无&ldquo;痛&rdquo;反应(脉搏和呼吸的变化轻微,无行为反应,与正常儿童不同)。 由结果看来,先天性无痛症患者似乎可分为两种类型:不完全型(如同例1)和完全型(如同例2)。存在有&ldquo;痛&rdquo;反应而无痛感觉的无痛症患者。 本工作结果从另一侧面为痛的两成分学说提供了依据。</p