利用低温等离子体技术脱除甲醛的研究

利用低温等离子体技术对脱除甲醛进行实验研究.设计了介质阻挡放电和电晕放电反应器,并分别加以高频交流高压和交直流叠加高压.比较了在不同工作参数下甲醛的脱除效果.实验结果表明,用介质阻挡放电脱除甲醛的脱除率及能量效率都比电晕放电的高,在低体积分数(10-5下)其脱除率可达99%以上,在高体积分数(2×10-4左右)其脱除率可达90%以上.这说明在甲醛体积分数相对于室内空气甲醛含量超标100倍内时,可利用介质阻挡放电脱除甲醛.     

等离子体引发CeO_2低温活性协同脱除空气中甲醛

为考察放电电压、甲醛初始体积分数和水体积分数对空气中甲醛脱除率的影响,选取催化剂MnO2、CeO2、TiO2分别与等离子体结合,在标准大气压、40℃条件下进行脱除甲醛实验。结果表明:空气中甲醛的体积分数为2.01×10-4、水的体积分数为1.0%、空速为13 650 h-1、放电电压为18 kV时,CeO2与等离子体结合的甲醛脱除率达98.5%;在相同条件下,单纯等离子体和单纯CeO2催化氧化(不放电)对甲醛的脱除率分别为62.5%和8.0%。等离子体与催化剂在脱除空气中甲醛的过程中产生了显著的协同作用。该研究为脱除空气中甲醛提供了理论参考。     

反应器参数对低温等离子体脱除NO的影响研究

设计并制作了实验用同轴圆柱介质阻挡放电反应器,研究了N2/NO体系下NO脱除效率随单双介质层、介质材料、放电间隙等反应器结构参数的变化情况;同时探讨了NO脱除过程中还原和氧化两种反应途径。结果表明：单介质反应器NO的脱除率和NO2的生成率要高于双介质反应器,但当供电电压较高时,双介质反应器的脱除效果较好;与石英双介质反应器比较可知,内外介质组成分别为陶瓷和石英的反应器对NO的脱除效果较好;放电间隙为1．5mm的反应器比3．5mm的NO脱除率高,特别是电压较低时,脱除优势更明显,但不利于NO2的生成。     

放电等离子体驱动下甲醛的光催化降解

采用介质阻挡放电等离子体结合TiO2光催化剂降解甲醛气体,在不同的放电电压下考察了催化剂载体、焙烧温度以及过渡金属离子掺杂对甲醛降解效果的影响.结果表明:TiO2/γ-Al2O3光催化剂的填充能显著提高甲醛的降解率和产物的选择性;甲醛降解率随放电电压的升高而增大,随焙烧温度的升高而下降,当焙烧温度为400℃、放电电压为...     

气液固三相放电反应器中等离子体化学过程增强

采用动态快速扫描UV-V is吸收光谱,研究了双向窄脉冲电源引发的等离子体化学反应器中,固体填料对气、液、固三相放电脱除废水中靛蓝二磺酸钠(ind igo carm ine,IDS)的影响.实验结果表明:固体填料的填充对气液两相放电反应器中的等离子体化学过程具有明显的增强作用;增强的程度由填料的特性决定,相同条件下,填充介质球填料时的处理效果好于填充导体填料时的,而且玻璃球介质填料又优于陶瓷填料;填充介质球的等离子体反应器中IDS的脱色为一级反应.     

介质阻挡放电脱除气态环己酮的研究

利用介质阻挡放电反应器进行了脱除挥发性有机物废气——环己酮的研究.通过改变极间电压,所加频率等条件,考察这些因素对环己酮脱除率的影响.通过研究发现:环己酮的脱除率随着极间电压,所加频率的升高而增加.当环己酮初始浓度为100 mL/m3,极间电压9 000 V时,环己酮的脱除率达到92.7%,证明介质阻挡放电对于流动态中的环己酮有很好的脱除效果.同时通过对反应过程中发射光谱的观察,对介质阻挡放电等离子体脱除环己酮的机理进行了初步的探讨.     

用FDTD法计算部分介质填充波导的截止频率

给出用时域有限差分（FDTD）方法计算电磁场问题的差分格式，详细介绍了FDTD法分析介质填充波导截止频率的计算过程。实例计算了空心矩形波导的截止频率，并与理论值进行比较；计算了填充部分介质时矩形波导和双脊波导的截止频率，获得了三脊波导的归一化截止频率谱图，给出填充不同介质时各主模式的截止频率。     

典型阴离子对纳米二氧化钛在载铁石英砂 多孔介质中迁移行为的影响

以纳米二氧化钛为研究对象,考察系列环境相关条件下(不同pH、离子类型与离子强度)纳米二氧化钛在载铁石英砂多孔介质中的迁移规律。结果表明,纳米二氧化钛在NaCl,NaNO_3和Na_2SO_4 3种溶液中的穿透曲线和滞留曲线没有显著差异,但与其他溶液相比,在NaH_2PO_4溶液中的穿透曲线和滞留曲线分别有明显的升高和降低;磷酸根离子会促进纳米二氧化钛在载铁石英砂多孔介质中的迁移行为。机理探究发现,由于PO_4~(3-)会被吸附至纳米二氧化钛和载铁石英砂多孔介质的表面上,增大纳米二氧化钛和多孔介质的表面Zeta电位,导致纳米二氧化钛与介质表面之间静电斥力的增加,从而加大纳米二氧化钛被吸附于多孔介质表面位点的难度,减少沉积;同时,纳米二氧化钛Zeta电位的增加会减少纳米二氧化钛颗粒间的碰撞团聚,导致其水力学粒径变小,从而促进其迁移行为。此外,PO_4~(3-)会与纳米二氧化钛竞争多孔介质表面的吸附位点,导致纳米二氧化钛可沉积位点的减少,增加迁移能力。     

沿面型介质阻挡放电氧化NO的试验研究

针对空间型介质阻挡放电脱除NO效率低、能耗高的问题,试验采用螺旋形沿面介质阻挡放电反应器,研究其氧化NO的影响因素,并对反应产物分布和能耗进行了分析.研究结果表明:当O_2体积分数很低或者为0时,NO主要通过还原途径转化为N_2;随着O_2体积分数的增加,NO通过氧化转化的途径逐渐占主导地位,总体的NO脱除率逐渐下降,NO_2生成率逐渐上升;NO入口体积分数的增大和停留时间的减少都会使NO脱除率降低,同时NO入口体积分数的变化对NO_2生成率的影响程度显著大于停留时间.NO在放电中的主要产物为N_2,NO_2和N_2O.当O_2体积分数为6%时,螺旋形沿面介质阻挡放电能量收益值为6.16g/(kW·h).     

竹炭负载二氧化钛光催化降解甲醛的研究

采用溶胶-凝胶法制备TiO2溶胶,以浸渍-过滤法将TiO2负载于颗粒竹炭的表面,制成竹炭负载二氧化钛的复合型光催化剂TiO2/BC,并对甲醛进行催化降解.结果表明:紫外光照射下TiO2/BC催化剂对甲醛有催化降解活性,光照3 h甲醛降解率达45.6%,负载次数以3次为佳;太阳光照射下甲醛降解率比日光灯照射下的高,紫外光照射下甲醛的降解率最高;当紫外灯强度达到一定值后,再增加照射强度并不能有效提高降解率.     

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-