固定床一步法合成二甲醚的催化剂研究

通过共沉淀浸渍法,制备出合成气一步法制二甲醚的具有甲醇合成功能和甲醇脱水功能的双功能催化剂,加入助剂硼酸对其进行改性,并在固定床连续反应器内进行实验。确定了含硼量对催化剂催化效果的影响,含硼量增大,转化率。选择性呈先增大后减小的趋势,含硼0.5％的催化剂效果最佳。对温度、压力、空速和氢碳摩尔比等反应条件的考察结果显示,当温度280℃、压力4．0MPa,空速1500h^-1、氢碳摩尔比1．5时,催化剂具的活性和洗择性达到最好,CO转化率为66．8％,DME的选择性为50．7％,DME的收率为33．9％。     

CO2加氢合成二甲醚的适宜工艺条件

采用甲醇合成催化剂C207和分子筛HZSM-5混合制得CO2加氢合成二甲醚双功能催化剂，并在微型固定床反应装置上进行了活性评价。考察了反应温度、压力、氢碳摩尔比、空速等工艺条件对催化反应的影响。结果表明，温度对催化剂活性影响显著，适当提高温度有利于提高反应速率，适宜的温度操作范围260～270℃，增加压力，提高氢碳摩尔比有利于提高CO2转化率、二甲醚收率；适宜的空速范围1500～3000h^-1。     

合成气制备工艺和二甲醚合成工艺的集成

在固定床反应器中,用3种典型的天然气造气工艺制备的合成气制备二甲醚,考察了温度、压力、空速等反应条件对催化剂性能的影响．实验结果表明,由于合成气一步法合成二甲醚是一个体积减小的反应,随着压力的增加,CO转化率增加;随着空速的增加,CO转化率降低;随着温度的升高,CO转化率先增加,达到一定值后,逐渐开始下降．分别用丹麦Topscpe甲醇合成催化剂和国产甲醇合成催化剂制备了DME合成催化剂,对其性能进行比较发现,前者具有较好的低温催化性能．用CH4-Air-H2O-CO2转化工艺制备的合成气,即含氮合成气合成二甲醚在适当增加压力的条件下,可取得较高的CO单程转化率和二甲醚回收率,且天然气的消耗量较少．     

化学液相沉积法改性ZSM-5沸石上的甲苯择形歧化反应:Ⅱ水蒸气处理与反应条件的影响

采用水蒸气对化学液相沉积硅改性HZSM-5催化剂进行了处理,考察了250～500 ℃时水热处理温度对催化剂在甲苯择形歧化反应中的催化活性和对二甲苯选择性的影响.实验结果表明,300～350 ℃时的水热处理效果较好,甲苯转化率和对二甲苯选择性分别达到23.5%和96.5%.在高对位选择性的催化剂上,详细考察了反应温度、反应压力、氢气与甲苯进料比和甲苯进料速率对甲苯转化率、对二甲苯选择性和收率的影响.实验结果表明,高压、较低温度、低液相空速有利于提高对二甲苯的收率,在反应温度420 ℃、压力2.5 MPa、甲苯的质量空速为1.5 h-1、氢烃摩尔比为2～3的条件下,甲苯转化率为25.8%,选择性为94.1%,对二甲苯收率为10.5%.     

Pd／γ-Al2O3催化剂合成甲基异丁基酮

采用等体积浸渍法制备了Pd/γ-Al2O3催化剂,用于丙酮一步法常压气相加氢制甲基异丁基酮.通过X射线衍射仪(XRD)及比表面积测定仪(BET)表征催化剂.考察了反应温度、氢酮摩尔比和催化剂中Pd含量等工艺条件对转化率和选择性的影响.经筛选,制备的0.5%Pd/γAl2O3催化剂,在反应温度为180℃、H2与丙酮的摩尔比为1.7∶1.0、进料液相空速为3.8h-1的条件下,效果最佳.丙酮转化率达28.0%,MIBK选择性达59.0%.     

加压条件下两段法天然气催化氧化制合成气催化剂的改进

以α-Al2O3为载体，在加压条件下，采用初湿浸渍法制备了镧助Ni／α-Al2O3部分氧化-重整催化剂和负载型钙钛矿型LCFM／α-Al2O3燃烧催化剂，考察了反应温度、压力、CH4与氧配比等因素对两段法甲烷催化氧化制合成气性能的影响。结果表明，在两段法催化氧化制合成气工艺中采用LCFM／α-Al2O3燃烧催化剂和镧助Ni／α-Al2O3部分氧化／重整催化剂，能够消除反应热点，降低反应的危险性。当温度为1000℃及体系压力为2MPa时，甲烷转化率约为85％，CO和H2的选择性接近90％，与热力学平衡值十分接近；增加原料气中的氧含量，可以提高甲烷的转化率，但CO和H2选择性随之降低。     

水溶性铑-膦络合物催化1-丁烯氢甲酰化反应研究

研究了在以水溶性铑膦络合物RhCl(CO)(TPPTS)2为催化剂的两相体系中，反应温度、压力、膦铑比、催化剂浓度、CO／H2分压比、底物浓度等对1-丁烯氢甲酰化反应的活性和区域选择性的影响．结果表明，RhCl(CO)(TPPTS)2对水／有机两相催化体系1-丁烯氢甲酰化反应表现出良好的活性和区域选择性，在100℃，2．5MPa，[TPPTS]／[Rh]=25时，生成戊醛的TOF高达2500h^-1，生成正戊醛的选择性达到87．5％．     

环氧乙烷吸收溶液合成碳酸乙烯酯管式反应工艺条件

在自行建立的管式反应器上,采用实验室开发的NY-2催化剂,以环氧乙烷(EO)吸收溶液和CO2为原料,进行合成碳酸乙烯酯(EC)连续过程研究.考察液空速、吸收溶液中EC与乙二醇(EG)摩尔比、EC与EO摩尔比、水含量、催化剂用量、反应压力和温度对反应的影响.通过实验研究,确定了较佳的连续反应条件:反应温度为(125±5)℃、反应压力为(3.5±0.5)MPa、催化剂质量分数不小于2%、吸收溶液中水的质量分数少于1.2%、EC与EO摩尔比为5、EG质量分数小于30%、空速小于0.67 h-1.在此条件下,EO的转化率大于98%,EC的选择性大于80%.     

Ru/TiO2催化剂上的催化湿式氧化处理H-酸废水反应性能研究

考察了反应温度、反应压力、反应气量、空速以及贵金属担载量等因素对Ru／TiO2催化剂催化湿式氧化法处理H—酸废水处理效果的影响．此外还利用X—荧光光谱(XFD)和X—射线粉末衍射(XRD)等表征手段研究了催化剂TiO2载体的杂质含量和晶型．结果表明：随着催化剂上活性组分担载量的增加，催化剂的催化活性逐步提高．在温度为240℃、压力为6．0MPa、空速为2．5h^-1、气量为150mL／min的反应条件下，经过担载量为ω(Ru)＝3％的Ru／TiO2催化剂的催化湿式氧化处理，模型废水中的COD去除率可达到99．8％．     

生物质合成气一步法合成二甲醚CuZnFeZr/HZSM-5催化剂的研究

以玉米秸秆热解气化所产生的生物质合成气为原料,研究了一系列催化剂的催化性能,其中优选出的CuZnFeZr/HZSM-5催化剂显示了较高的原料气CO转化率以及目标产物二甲醚的选择性.同时系统研究了温度、压力、空速等反应条件对于该反应的影响.通过实验优化得到适合该催化剂的反应条件为:反应温度260～270℃、反应压力约3.0 MPa,合成气空速为1500 h-1.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Jane Eyre——A Feminist In The 19th Century

In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-