Application of kaolin in the synthesis of Y zeolite and dimethyl ether

高岭土是一种以高岭石和埃洛石为主要成分的粘土类集合体矿物原料，应用范围涉及工业部门的许多领域，在催化中也有着广泛的应用。通过TEM、SEM、XRD和IR等表征手段，分析结果表明，龙岩高岭土产品主要成分为高岭石，埃洛石次之，不同种类的产品还有不同量的水云母、石英等。 高岭土在催化中最重要也是最普遍的应用是作为FCC（FluidCatalyticCracking）催化剂的原料。原位晶化合成的分子筛裂化催化剂因其优异的催化性能广泛应用于石油炼制领域。本文以龙岩高岭土为原料，采用原位晶化法合成用于FCC催化剂的Y型分子筛。通过高岭土原料的选择、高岭土微粒前处理温度的控制、初始投料比例和晶化时间的调节...Kaolin is a kind of mineral clay mainly composed of kaolinite and halloysite. Its application involves a lot of industrial areas. Catalysis industry is one of them. By use of TEM、SEM、XRD and IR, we found that the main component in Longyan Kaolin was kaolinite; halloysite took the second place. There were still some quartaz and hydromica in Longyan kaolin. One of the most important applications...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：20012507

磁固相萃取-液相色谱法测定环境水样中有机紫外防晒剂

采用自制的聚离子液体功能化磁性材料有效富集有机紫外防晒剂,并与高效液相色谱-二极管阵列检测器(HPLC-DAD)联用,建立了环境水样中痕量有机紫外防晒剂的检测方法。研究系统考察了解吸溶剂、吸附和解吸时间、样品pH值、离子强度等因素对萃取性能的影响。在最佳萃取条件下,水杨酸辛酯的线性范围为0.5～200.0μg/L,其他有机紫外防晒剂的线性范围为0.2～200.0μg/L; 6种目标物的检出限(LOD,S/N=3)和定量限(LOQ,S/N=10)分别为0.009～0.13μg/L和0.031～0.43μg/L。所建方法成功用于实际环境水样中有机紫外防晒剂的测定,不同加标水平下目标物的加标回收率为71.4%～120%,相对标准偏差均低于10%。研究表明,所建方法具有操作简便、萃取速度快、灵敏度高和环境友好等特点,可用于环境水样中有机紫外防晒剂的检测

Helix-shaped Carbon Nanotubes

[中文文摘]用含铈的催化剂(Ce/Fe,Ce/Co和Ce/Ni)催化裂解CH4合成了螺旋形碳纳米管,而用不含铈的催化剂(Mg/Fe,Mg/Co和Mg/Ni)制备的碳纳米管没有出现螺旋形.结果表明,催化剂中的Ce对螺旋形碳纳米管的生成起了重要作用.[英文文摘]By using Ce/Fe, Ce/Co and Ce/Ni catalysts, carbon nanotubes were synthesized in high yield from decomposition of CH4. TEM results show that a fraction of the tubes are helixshape compared with the products synthesized with Mg/Fe, Mg/Co and Mg/Ni catalysts, which are more or less twisted. The results indicate that Ce plays an important role in the formation of helixshaped carbon nanotubes.国家自然科学基金(29773037,29933040,20023001); 福建省自然科学基金(9910001)资助项目

Validity and Reliability of the Chinese Version of the Early Signs Scale of Schizophrenia

信教还是不信教?这是一个决策问题。行为决策的两类基本理论模型(分析式系统和启发式系统)都尝试着对这个问题进行解释。期望价值理论(属于分析式系统)产生于对&quot;帕斯卡的赌注&quot;的分析;齐当别抉择模型(属于启发式系统)被用于解释为什么&quot;骆驼穿过针的眼,比财主进神的国还容易&quot;。这两类模型用决策科学的语言,将信不信宗教问题简化为可证伪的选择问题。其审题的不同视角,反映了期望家族理论与启发式家族理论之间的碰撞。</p

The Factors of Preparation of Carbon Nanotubes by Catalytic Decomposition of Methane

以柠檬酸法制备的Fe MgO、Co MgO和Ni MgO为催化剂 ,CH4 为碳源气 ,H2 为还原气 ,在 873、973和 10 73K制备出碳纳米管 ,通过TEM和拉曼光谱表征 ,讨论了催化剂、制备温度、反应时间等因素对碳纳米管形貌、产率和内部结构的影响 .结果表明 :不同的催化剂在相同的温度下制备的碳纳米管的形态和内部结构有很大的差异 .其中Fe MgO催化剂制备的碳纳米管管径粗 ,且大小不均匀 ,而Ni MgO催化剂制备的碳纳米管管径较细、较均匀 .碳纳米管的产率随着裂解温度的变化而改变 .Fe MgO催化剂制备碳纳米管的产率随制备温度的升高而提高 ,而Ni MgO催化剂制备碳纳米管的产率随制备温度的升高而降低 .Fe MgO催化剂制备碳纳米管 ,在10 73K甚至更高的制备温度才能达到其最高产率 .Co MgO催化剂制备碳纳米管的产率在 973K左右产率较高 ,而用Ni MgO催化剂制备碳纳米管 ,则在 873K甚至更低的制备温度就能达到最高产率 .反应时间与碳纳米管的产率不成正比 ,有一最佳反应时间 ,如Ni MgO催化剂的最佳反应时间为 2h .Using Fe MgO?Co MgO and Ni MgO catalysts preparated by citric acid method, carbon nanotubes (CNTs) were synthesized from decomposition of methane at 873 K, 973 K and 1013 K, respectively, and were characterized by TEM and Raman spectra. The effects of catalysts, preparation temperature and reaction time on the shape, yield and inter-structure of carbon nanotubes were discussed. TEM results and Raman spectra show that the shapes and inter structures of carbon nanotubes produced on different catalysts at the same temperature are quite different. Carbon nanotubes synthesized on Fe MgO incline to be rods, with very thick wall, and the diameter varied greatly from 10 nm to 80 nm. However, the diameter of carbon nanotubes produced on Co MgO is about 35 nm, and about 20 nm on Ni MgO. As can see from the Raman spectra, the G peaks of carbon nanotubes produced on the three catalysts shift slightly, which indicate the difference of the inter structure of nanotubes. The experiments show that the yield of carbon nanotubes varied with decomposition temperature. Using Fe MgO catalysts, yield of carbon nanotubes grows with the decomposition temperature. However, using Ni MgO catalysts, the yield drops when the temperature increases. The reaction temperature with the largest yield of carbon nanotubes is higher than 1013 K on Fe MgO catalysts, about 973 K on Co MgO catalysts, and lower than 873 K on Ni MgO catalysts, respectively. The results also show that the yield of carbon nanotubes does not increase with the decomposition time. There is a saturation time of the carbon nanotube growth. The carbon nanotubes do not grow any more when the saturation time reaches. For example, on Ni MgO catalysts, the carbon nanotubes stop growing after decomposition of CH 4 for 2 h.国家自然科学基金 (2 97730 37,2 99330 40 ,2 0 0 2 30 0 1);; 福建省自然科学基金 (E9910 0 0 1,E0 0 10 0 0 6 )~

The factors of preparation of carbon nanotubes by catalytic decomposition of methane

Using Fe-MgO, Co-MgO and Ni-MgO catalysts preparated by citric acid method, carbon nanotubes (CNTs) were synthesized from decomposition of methane at 873 K, 973 K and 1013 K, respectively, and were characterized by TEM and Raman spectra. The effects of catalysts, preparation temperature and reaction time on the shape, yield and inter - structure of carbon nanotubes were discussed. TEM results and Raman spectra show that the shapes and inter-structures of carbon nanotubes produced on different catalysts at the same temperature are quite different. Carbon nanotubes synthesized on Fe-MgO incline to be rods, with very thick wall, and the diameter varied greatly from 10 nm to 80 nm. However, the diameter of carbon nanotubes produced on Co-MgO is about 35 nm, and about 20 nm on Ni-MgO. As can see from the Raman spectra, the G peaks of carbon nanotubes produced on the three catalysts shift slightly, which indicate the difference of the inter-structure of nanotubes. The experiments show that the yield of carbon nanotubes varied with decomposition temperature. Using Fe-MgO catalysts, yield of carbon nanotubes grows with the decomposition temperature. However, using Ni-MgO catalysts, the yield drops when the temperature increases. The reaction temperature with the largest yield of carbon nanotubes is higher than 1013 K on Fe-MgO catalysts, about 973 K on Co-MgO catalysts, and lower than 873 K on Ni-MgO catalysts, respectively. The results also show that the yield of carbon nanotubes does not increase with the decomposition time. There is a saturation time of the carbon nanotube growth. The carbon nanotubes do not grow any more when the saturation time reaches. For example, on Ni-MgO catalysts, the carbon nanotubes stop growing after decomposition of CH4 for 2 h

A Study on Catalytic Synthesis of DME from Methanol by Kaolin

[中文文摘]比较研究了高岭土的结构特征,采用常压微型反应装置评价了高岭土作为催化甲醇制二甲醚催化剂的活性,并对高岭土进行了酸处理改性研究.结果表明,高岭土中高结晶度的高岭石有利于催化甲醇脱水制二甲醚,酸处理改性能提高高岭土的催化活性.[英文文摘]The structure and acid treatment of the kaolin were studied and compared and their catalytic activity for DME synthesis from methanol was evaluated by using a normal pressure micro-reactor.Here we compare the catalytic activity of two different kinds of kaolin. DME conversions under the condition of (0.1 MPa) and 320℃ over them are 43% and 69.3% separately.The two kinds of kaolin are characterized by the method of TEM,SEM and XRD.The results showed that kaolinite with high crystalization in kaolin may be favorable to the reaction of dehydration of methanol into DME. To im2 prove the catalytic activityof kaolin ,we treat oneof the kaolinwith sulfuric acid.DMEconversionover kaolin treatedwith acid can be improved from 43% to 82.3%.But DME conversion falls when kaolin is treated with more acid.Because when kaolin is treated by too much acid ,the numberof strong acid sites growswhile the numberof weak acid sitesfalls; and strong acid sites are requiredfor the dehydration of methanol to olefins while the weak acid sites are active for ether formation. The results showthat acid treatment of kaolin can improve the catalytic activityof kaolin while too much acid is not favorable to the reaction of dehydration of methanol into DME by resulting in more subsidiary reactions.福建省科技攻关计划重大项目(2002H013)资助

新疆人口地域系统理论与方法体系研究

新疆人口地域系统的理论和方法体系研究是横向和纵向两方面项目资助完成的综合性研究,一方面是和新疆有关厅局委、地州等合作的横向项目,具体包括：受新疆人口和计划生育委员会委托完成的“新疆人口发展战略研究”、“新疆人口发展功能区研究”,自治区建设厅委托的“新疆小城镇发展战略研究”;自治区发改委委托的“小城镇经济发展战略研究”子专题“小城镇人口预测及其承载力研究”以及地州、县级、乡等城镇体系规划、村镇体系规划、新农村建设规划等都涉及到区域人口发展的项目。另一方面是纵向的中国科学院知识创新工程重点项目专题“城市化空间形态的资源环境效应研究”、中国科学院“西部之光”人才培养计划项目“天山北坡绿洲城镇化进程中..

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel