电沉积纳米ZnO薄膜

在硝酸锌溶液中电沉积ZnO，通过正交试验方法研究槽液浓度、pH值以及电流密度对纳米ZnO薄膜电沉积的作用。用XRD分析了纳米ZnO的组织、结构与成分，SEM获得了纳米ZnO的表面形貌。     

16×10.7 Gb/s 1 600 km普通单模光纤环路传输研究

利用双折射光纤环设计了可调功率均衡滤波器,实现了16路16×10.7 Gb/s NRZ码、超过1 600 km常规单模光纤(SMF)的系统传输及性能测试,信道误码率均小于3×10-5(FEC纠错前).数值仿真并实验研究了对单环长度240 km、损耗超过80 dB的环路16路10.7 Gb/s波分复用(WDM)系统传输的优化.传输7圈后,功率均衡器降低了信道功率不平坦度超过5 dBm.     

溶剂对环氧乙烷催化水合制乙二醇的影响

研究了NY催化剂催化环氧乙烷水合制乙二醇(EG)过程中,溶剂、催化剂添加量和水与环氧乙烷的摩尔比(简称水比)对EG选择性的影响。实验结果表明,以丙三醇作为溶剂使催化剂进行循环,能提高EG的选择性,效果好于以生成的EG作为溶剂循环催化剂。催化剂添加量、水比和溶剂添加量对EG选择性具有较大影响,其中溶剂添加量对EG选择性的影响最显著。在低水比(1.0~4.0)条件下,EG质量分数小于30%、催化剂质量分数大于7.2%时,EG选择性稳定在95.63%~97.92%,平均值为96.80%,此结果对于进一步降低EG合成工艺的能耗具有指导意义。     

Mixed oxide supported hydrodesulfurization catalysts—a review

Support effects form important aspect of hydrodesulfurization (HDS) studies and mixed oxide supports received maximum attention in the last two decades. This review will focus attention on studies on mixed oxide supported Mo and W catalysts. For convenience of discussion, these are divided into Al₂O₃ containing mixed oxide supports, TiO₂ containing mixed oxide supports, ZrO₂ containing mixed oxide supports and other mixed oxide supports containing all the rest. TiO₂ containing mixed oxides received maximum attention, especially TiO₂–Al₂O₃ supported catalysts. A brief discussion about their prospects for application to ultradeep desulfurization is also included. An overview of the available literature with emphasis on research carried out in our laboratory form the contents of this publication.     

聚丙烯酰胺/氧化石墨纳米复合材料的研究

氧化石墨具有良好的层状结构，其层间具有丰富的官能团，能与有机聚合物形成插层纳米复合材料进而改善材料的性能．采用层离吸收-原位聚合法制备了聚丙烯酰胺／氧化石墨纳米复合材料，并采用XRD、HREM及DSC等对其结构和性能进行了表征。结果表明，聚丙烯酰胺与氧化石墨两者之间存在着较强的相互作用，材料的玻璃化转变温度得到提高，层离吸收-原位聚合法是获得聚丙烯酰胺／氧化石墨层纳米复合材料的有效途径，聚丙烯酰胺在氧化石墨中存在着多种排列方式，不同层间距(1．6nm和2．8nm)的聚丙烯酰胺／氧化石墨纳米复合结构同时存在。     

盐浓度对交联聚合物线团形态的影响

用核孔膜过滤法 (过滤体积对过滤时间作图 )、动态光散射法 (DLS)和扫描电镜法 (SEM )研究了交联反应前后盐 (NaCl)浓度变化对低浓度HPAM与AlCit形成的交联聚合物溶液 (LPS)中交联聚合物线团 (LPC)形态的影响。所用HPAM相对分子质量 1.1× 10 7～ 1.4× 10 7,LPS中HPAM与Al的质量比 2 0∶1,HPAM浓度 0 .1或 0 .2 g/L ,交联反应温度 40℃ ,时间 7天。实验结果表明 :①LPC的平均水力半径Rh(DLS测定值 )随交联反应时盐浓度的增大先减小后增大 ,盐浓度由 0 .5 g/L增加到 2 g/L时Rh 由 45 0nm迅速减小到 2 5 0nm ,盐浓度增加到 2 0 g/L时Rh达到最小值 16 0nm ,此后随盐浓度的继续增加Rh 有所增大 ;盐浓度 0 .5和 2 .0 g/L时Rh 的SEM测定值分别为45 0和 2 5 0nm ,与DLS结果一致。②交联反应完成后改变LPS的盐浓度 ,也可改变LPC的Rh 值 ,但改变幅度较小 ;盐浓度 0 .5 g/L时形成的LPS ,当盐浓度增加至 2 g/L时 ,Rh 值由 45 0nm减小至 35 9nm ,大于盐浓度 2 g/L时形成的LPS的Rh 值 (2 46nm) ;盐浓度 2 g/L时形成的LPS ,当盐浓度减少至 0 .5 g/L时 ,Rh 值由 2 46nm增大至32 6nm ,小于盐浓度 0 .5g/L时形成的LPS的Rh 值 (4 5 0nm)。用盐浓度改变引起LPC水化层厚度改变 ,线团收缩或舒张解释盐浓度改变时Rh 测定值的     

高速光通信系统中的色散问题及其补偿研究

当光纤通信系统单信道速度升级到40Gbit/s及以上时，色度色散（CD）和偏振模色散（PMD）已经成为严重影响系统性能的主要因素。本文主要从补偿的必要性、关键技术、主要方法和解决方案等方面分别对CD和PMD及其补偿进行了较详细的研究。     

Microstructure-Property Correlation in AI_4C_3 Dispersion Strengthened Al Composite

The microstructure and tensile properties of Al_4C_3 dispersion strengthened Al composite fabricatedby reaction milling technique were investigated.It is indicated that the rod-like Al_4C_3 dispersoidshaving a diameter of 0.02-0.03 μm and a length of 0.1-0.3μm are formed by reaction of C with Al,and uniformly distributed in the Al matrix.The interface between Al_4C_3 and Al is clean and theinterfacial bonding is good.The matrix consists of the subgrains which have the size of 0.3-0.4μm,and most of the Al_4C_3 dispersoids are distributed on the subgrain boundaries.The 11 vol.-%Al_4C_3/Al composite exhibits an UTS (ultimate tensile strength) of 400 MPa and anelongation-to-failure of 8.0%.     

仿生矿化的研究Ⅰ．文石型碳酸钙的合成

在聚乙二醇（ＰＥＯ）存在下，ＣａＣｌ２和Ｎａ２ＣＯ３反应生成了类似红鲍鱼壳的含有ＰＥＯ的碳酸钙──高聚物复合材料。Ｘ－衍射和电镜照片显示，它有两种微观结构：外层为文石型和方解石型结构，内层为针状文石型结构。热重分析表明，该材料中含有３％左右ＰＥＯ。结果说明，聚合物对碳酸钙晶核的形成和晶体的生长有很大影响，并对其形成机理进行了初步探讨。     

Nitric oxide reduction and carbon monoxide oxidation over carbon-supported copper-chromium catalysts

Carbon supported copper-chromium catalysts are shown to be very active for both the reduction of nitric oxide with carbon monoxide and the oxidation of carbon monoxide with oxygen. Mixed copper-chromium oxide active phases have good activity in the simultaneous removal of nitric oxide and carbon monoxide from exhaust gases. The influence of several catalyst variables has been investigated. The activity per volume of catalyst increases with increasing loading, while the intrinsic activity shows a maximum around C/M=100−50. An optimum catalyst for nitric oxide reduction and carbon monoxide oxidation has a copper/chromium ratio of 2/1. The apparent activation energy for the carbon monoxide oxidation over carbon supported copper-chromium catalysts is 77 kJ/mol, suggesting that the Cu---O bond rupture is the rate-limiting process. The reduction of nitric oxide takes place at higher temperatures. Since all catalysts have a low selectivity for molecular nitrogen formation at lower temperatures, the dissociation of nitric oxide is probably rate determining, resulting in a slightly reduced catalyst system. In an excess of carbon monoxide the reaction is first-order in nitric oxide and zero-order in carbon monoxide. Moisture inhibits the reaction by reversible competitive adsorption, whereas carbon dioxide does not. Oxygen completely inhibits the reduction of nitric oxide due to the more rapid reoxidation of the catalytic sites compared to nitric oxide. Therefore, the reduction of nitric oxide takes place only when all oxygen has been converted and, hence, is shifted to higher temperatures. As a possible consequence, the production of nitrous oxide is reduced. Nitric oxide and molecular oxygen react preferentially with carbon monoxide, so, in an excess of oxidizing component, gasification of the carbon support occurs at higher temperatures after carbon monoxide has been completely consumed.