介孔Ni基催化剂上乙烷氧化脱氢制乙烯

以十二烷基硫酸钠为模板剂,尿素为沉淀剂制备了介孔氧化镍,并将该方法成功拓展至介孔NiMgO催化剂的合成.考察了这两种催化剂以及采用溶胶-凝胶法制备的纳米氧化镍催化剂对乙烷氧化脱氢反应的催化性能.结果表明,介孔氧化镍较纳米氧化镍在相同乙烷转化率条件下乙烯选择性更高,且前者反应温区大为扩展,因而乙烯收率更高.介孔氧化镍经Mg调变后,其催化性能进一步提高,在450oC,C2H6:O2:N2=1:1:4和GHSV=18000ml/(g·h)条件下,介孔NiMgO催化剂上乙烷转化率和乙烯收率分别为56.6%和30.1%,其乙烯收率远高于纳米氧化镍(15.9%)和介孔氧化镍(22.5%)

介孔Ni基催化剂上乙烷氧化脱氢制乙烯

以十二烷基硫酸钠为模板剂,尿素为沉淀剂制备了介孔氧化镍,并将该方法成功拓展至介孔NiMgO催化剂的合成.考察了这两种催化剂以及采用溶胶-凝胶法制备的纳米氧化镍催化剂对乙烷氧化脱氢反应的催化性能.结果表明,介孔氧化镍较纳米氧化镍在相同乙烷转化率条件下乙烯选择性更高,且前者反应温区大为扩展,因而乙烯收率更高.介孔氧化镍经Mg调变后,其催化性能进一步提高,在450oC,C2H6:O2:N2=1:1:4和GHSV=18000ml/(g·h)条件下,介孔NiMgO催化剂上乙烷转化率和乙烯收率分别为56.6%和30.1%,其乙烯收率远高于纳米氧化镍(15.9%)和介孔氧化镍(22.5%)

Relationship between BMI,WHR and brachial arterial vasodilation function of middle-aged patients with impaired glucose tolerance

探讨体重指数(bMI)、腰臀比(WHr)与中年糖耐量减低(IgT)者血管内皮功能的关系。行标准75g口服葡萄糖耐量试验(75gOgTT),诊断为IgT者101例,年龄在45-59岁。对研究对象检测bMI、WHr、肱动脉血流介导的内皮依赖性血管舒张功能(以△dIA-P%表示)、硝酸甘油介导的非内皮依赖性血管舒张功能(以△dIA-n%表示)、C-型利钠肽(CnP)、内皮素-1(ET-1)、OgTT2H血糖、空腹血糖及胰岛素,计算胰岛素抵抗指数(HOMA-Ir),并进行统计学分析。bMI、WHr与空腹血糖、Og-TT2H血糖、空腹胰岛素、HOMA-Ir、ET-1、CnP、△dIA-P%具有相关性,而且bMI与△dIA-n%具有相关性。bMI正常、超重与肥胖三组比较,正常组与肥胖组之间ET-1、CnP、△dIA-P%、△dIA-n%、空腹血糖、OgTT2H血糖、空腹胰岛素和HOMA-Ir均具有显著性差异,而超重组与肥胖组之间ET-1、空腹血糖、OgTT2H血糖、空腹胰岛素、HOMA-Ir具有显著性差异。WHr正常与异常二组比较,空腹血糖、OgTT2H血糖、空腹胰岛素、HOMA-Ir、ET-1、CnP、△dIA-P%具有显著性差异。中年IgT者血管内皮功能、糖代谢及胰岛素敏感性受体脂含量、体脂分布的影响,bMI、WHr与血管内皮功能障碍、胰岛素抵抗、糖代谢异常之间存在相关性,而且二者与胰岛素抵抗、糖代谢异常的相关性较血管内皮功能障碍的相关性大,腹型肥胖是胰岛素抵抗的重要相关因素。The purpose of this study was to discuss the relationship between MI,WHR and vascular endothelium function of middle-aged patients with impaired glucose tolerance.101 persons diagnose4d as IGT,aged between 45-59 were detected on BMI,WHR,△Dia-P%,△Dia-N%,CNP,ET-1,OGTT2h glucose,fasting blood glucose and insulin after taking 75gOGTT.HOMA-IR was caculated and statistics was analyzed.The result showed that BMI and WHR had relationship with BMI,WHR,△Dia-P%,ET-1,OGTT2h glucose,fasting blood glucose,fasting insulin,CNP and HOMA-IR,and BMI had relationship whith △Dia-N%.Compared with those of the overweight group and obesity group,ET-1,CNP,△Dia-P%,△Dia-N%,fasting blood glucose,OGTT2h glucose,fasting insulin and HOMA-IR were different between the normal group and the obesity group.ET-1,fasting blood glucose,OGTT2h glucose,fasting insulin and HOMA-IR were significantly different between overweight group and obesity group.The comparison of fasting blood glucose,OGTT2h glucose,fasing insulin,HOMA-IR,ET-1,CNP and △Dia-P% were different between normal WHR and abnormal WHR.It was concluded that the percentage of body fat and distribution of body fat influenced vascular endothelium function,glucose metabolism and insulin sensitivity of middle-aged patients with impaired glucose tolerance.BMI and WHR were related to vascular endothelium dysfunction,insulin resistance,abnormal glucose metabolism.福建省自然科学基金资助项目(X0850028/2008J0272

乙烷氧化脱氢制乙烯纳米Sm_2O_3催化剂的研究

采用XRD,TEM,BET,CO2 TPD,O2 TPD和催化剂性能评价等方法对溶胶 凝胶法制备的纳米Sm2O3的物相、颗粒度、比表面、碱性、吸附活化氧物种的能力和催化剂的ODE性能进行了表征和评价,并与常规Sm2O3进行了比较.实验结果表明,纳米Sm2O3催化剂具有较佳的低温ODE反应性能,在500～600℃的温度范围内,纳米Sm2O3的乙烷转化率和乙烯选择性均优于常规Sm2O3,其原因主要与纳米催化剂体系具有较大比表面,较多的表面缺陷位,较弱的碱性和不同于常规催化剂体系的物相结构并因此更有利于吸附和活化氧物种等因素有关.采用高温原位显微Raman光谱对纳米Sm2O3上ODE反应活性氧物种的表征结果表明,O22-是Sm2O3催化剂上ODE反应的活性氧物种

~(18)O isotopic study of photo-induced formation of peroxide species on cubic Nd_2O_3

采用原位显微rAMAn光谱和18O同位素示踪技术,以325 nM激光为激发光源,对立方nd2O3上过氧物种的光诱导生成过程进行了详细表征,进一步证实过氧源于分子氧对晶格氧的氧化反应.结果还表明,325 nM激光在室温下即可诱导过氧的生成,在实验条件下,生成的过氧物种可与nd2O3的晶格氧发生快速的氧交换反应,位于nd2O3体相的晶格氧也可迁移至样品表层进而参与过氧的生成.325 nM激光照射有助于促进晶格氧的迁移以及晶格氧与分子氧之间的氧交换反应.Photo‐induced formation of peroxide species on cubic Nd2O3 was studied by in situ microprobe Raman spectroscopy using 18O as a tracer and a 325‐nm laser as an excitation source.The results confirmed that the peroxide ions were formed through photooxidation of the lattice oxygen species in neodymium sesquioxide by molecular oxygen species.Under UV excitation(λ = 325 nm), the reaction between O2 and O2- could take place at room temperature.A fast oxygen exchange between the peroxide ions and the lattice oxygen species in Nd2O3 took place under the experimental condi‐tions studied.Also, bulk lattice oxygen species in Nd2O3 could migrate to the surface layer and par‐ticipate in the formation of peroxide ions.The migration of lattice oxygen species and the oxygen exchange between lattice oxygen and peroxide ions were promoted by UV laser irradiation.supportedbytheNationalBasicResearchProgramofChina(973Program;2010CB732303); theNationalNaturalScienceFoundationofChina(21173173;21033006;21373169); theProgramforChangjiangScholarsandInnovativeResearchTeaminUniversity(IRT1036)~

In situ Time-resolved FTIR and Raman Characterizations of the Partial Oxidation of Methane to Synthesis Gas over Ir/SiO_2 Catalyst

[中文文摘]采用原位时间分辨红外光谱和原位显微Raman光谱技术对Ir/SiO2 上甲烷部分氧化 (POM)制合成气反应的初级产物和反应条件下催化剂表面物种进行了跟踪考察 ,实验结果表明 ,在H2 预还原的新鲜Ir/SiO2 表面 ,CO是V(CH4)∶V(O2 )∶V(Ar) =2∶1∶45混合气反应的初级产物 ,因而甲烷的直接氧化过程是CO生成的主要途径 ;而在稳态反应条件下 ,CO生成的途径可能主要来自CO2 和H2 O与催化剂表面积碳物种 (CHx)和 /或CH4的反应 .催化剂上生成的积碳可能是导致稳态条件下Ir/SiO2 上POM反应机理不同于H2 预还原的新鲜催化剂的主要原因。[英文文摘]In situ time-resolved FTIR and in situ microprobe Raman spectroscopies were used to follow the primary products as well as the surface and gas phase species formed during the reaction of partial oxidation of methane (POM) to synthesis gas over Ir/SiO 2 catalyst. The results suggested that direct oxidation of CH 4 to CO is the dominant pathway of POM reaction over the freshly reduced Ir/SiO 2 catalyst, while the dominant schemes of CO formation over the catalyst under the steady state reaction condition are probably via the reactions of CO2 and H2O with the deposited carbon species (CHx) and/ or CH4 . The mechanistic difference between the POMto synthesis gas over freshly reduced Ir/ SiO2 catalyst and the catalyst under the steady state reaction may have resulted from the formation of significant amount of deposited carbon species in the latter system.国家重点基础研究发展规划 (No.G1999022408); 国家自然科学基金(No.20021002)资助项目

C/SiC表面SiC涂层氧化的显微CT无损检测与分析

对C/SiC复合材料表面SiC涂层在1300℃干氧和湿氧环境中退火处理60 h,利用显微CT技术对高温氧化后的SiC涂层进行无损检测。通过重构SiC涂层不同深度的氧化形貌,并利用SEM、EDS和XRD进行辅助验证,得到沿SiC涂层表面和厚度方向的氧化形貌。结果表明:显微CT能有效地检测氧化后SiC涂层中存在的氧化产物SiO2及其氧化深度,其在表面及深度方向均呈非均匀分布;在干氧环境中SiC涂层的氧化面积沿着涂层的深度方向呈减少趋势,而在湿氧环境中SiC涂层的氧化面积沿着涂层的深度方向呈先增加后递减的趋势,验证了C/SiC复合材料表面SiC涂层在干氧和湿氧中不同的氧化机制

The Research on Citizen Satisfaction Towards Guangxi Government Affairs Service——From the Perspective of the Masses to Handle Affairs

广西政务服务"十二五"规划的实施已经结束,对在此期间所取得的成就及存在的问题进行总结十分有必要。通过对到政务服务中心办事的群众进行问卷调查、收集数据,运用SPSS21.0分析软件对所得数据进行分析,得出政务中心窗口人员工作态度、政务信息公开情况、政务网站建设、规章制度与办事群众的满意度息息相关的结论。在此基础上提出完善政务服务体系建设、提高工作人员素质、建立多规合一政务服务平台等完善路径,以推动广西政务服务工作的发展以及服务型政府的建设。Even though Guangxi government affairs service of the ＂12th five- year＂plan has come to an end,it is very necessary to summarize the achievements and the problems in this period. Based on a questionnaire to the masses who come to deal with affairs in the government service center,we collected and used SPSS21. 0 software to analyze the data. Through the analysis,we got the result that there is strong correlation between the masses’ satisfaction and the following factors such as working attitude of government staff,the situation of government information publicity,the website construction and the rule establishment of government service center. Based upon the result,we put forward several recommendations： consummating service system construction,improving staff quality and establishing a service unity platform of multi- rule to promote the development of the Guangxi government affairs service and the construction of a service- oriented government.国家自然科学基金(T1263009)； 广西民族大学研究生教育创新计划(gxun-chxs201528)； 硕士研究生普通田野调查项目(gxun-sdc201522