氧浓度对调节NOx氧化度协同CABR法脱硝性能及菌群结构的影响

针对调节NO _x 氧化度协同化学吸收-生物还原法在不同氧气体积分数下的NO _x 去除性能及微生物群落结构的动态变化,研究了氧气体积分数对该体系的影响机制。结果表明,调节模拟烟气中NO _x 氧化度为50%时,烟气中包含的氧气体积分数在0~8%的范围内,化学吸收-生物还原（CABR）体系的脱硝效率稳定在99%以上;当氧气体积分数达到10%时,系统脱硝效率仍可超过94%。EPS含量检测显示,氧体积分数从0增加至5%,导致LB-EPS中PN/PS值由1.72上升到2.18,TB-EPS中PN/PS值从1.21降至0.706。高通量测序结果表明,不同氧气体积分数下微生物的优势菌门均为Proteobacteria,其相对丰度达到55.0%~85.7%,它是典型的具有好氧反硝化能力的菌门,这保证了该系统脱硝性能的稳定。综上所述,氧体积分数对调节NO _x 氧化度协同CABR集成系统的脱硝效果影响较小,为烟气中NO _x 的去除提供了新的思路。     

H2在MoxSy团簇上吸附解离的尺寸效应研究

浆态床加氢工艺可以处理不同来源的劣质重油、渣油,氢气的活化是重油加氢处理过程中发生的主要反应之一。钼基催化剂的分散性是影响重油加氢活性的关键因素。构建了Mo₇S₁₅、Mo₁₂S₂₆、Mo₁₈S₃₉、Mo₂₅S₅₄和Mo₃₃S₇₁团簇,利用密度泛函理论研究了团簇自身的稳定性、活性以及H₂在不同尺寸团簇上的吸附与解离过程。结果发现,在目前所建立的团簇中,其尺寸越小,结合能越低,最高占据分子轨道-最低未占分子轨道(HOMO-LUMO)能隙值越小,团簇稳定性越弱,活性越强。H₂在簇上的稳定吸附位点为边缘位点。随团簇尺寸增大,吸附能分别为-64.25、-34.60、-34.14、-7.20、-6.82 kJ/mol,吸附能绝对值减小,氢气分子与团簇的相互作用减弱,并且解离能逐渐增大,分别为13.76、33.14、53.64、60.75、64.47 kJ/mol。目前的结果表明,团簇尺寸越小,氢气的吸附解离越容易,显示出更高的活性。     

Static and dynamic corrosion behavior of SnO2-doped AZS slip cast refractory in SLS glass

The corrosion behavior of a tin IV oxide-doped AZS-refractory, subject to static and dynamic corrosion testing at 1370˚C in soda-lime-silica glass, was studied considering the effect of the microstructural features on corrosion. The refractory was synthesized by slip cast methods through reaction sintering of alumina and zircon raw materials using SnO₂ as a sintering agent. SnO₂ had a considerable influence in the enhanced alumina/zircon reaction sintering and the subsequently evolved microstructures of an interlocked Zr_(1-x)Sn_(x)O₂ solid solution reinforced alumina-mullite composite. The process kinetics of the refractory corrosion followed reasonably well the predicted dependence on the square root of angular velocity under forced convection corrosion. Glass chemical corrosion and erosion of the refractory, under static and dynamic glass conditions, respectively, revealed the Zr_(1-x)Sn_(x)O₂ solid solution-rich mullite matrix as providing the most corrosion resistance and glass compatibility.     

Ca1-3x/2Al2Si2O8:xEu3+荧光粉的发光和光温传感特性

为了探究稀土离子掺杂铝硅酸盐的光温特性,本文采用燃烧合成法制备了系列荧光粉材料Ca_1-3x/2Al₂Si₂O₈:xEu³⁺。X射线衍射结果表明掺杂Eu³⁺离子不会改变基质CaAl₂Si₂O₈的晶体结构。荧光光谱结果表明该荧光粉在近紫外光区域具有较强吸收,当被波长为393 nm的近紫外光激发后,其最大特征发射峰为611 nm,且Eu³⁺离子的最佳掺杂浓度为0.05。利用上升时间测温法研究了CaAl₂Si₂O₈:Eu³⁺荧光粉的光温传感特性,结果表明:随着Eu³⁺掺杂浓度的增加,上升时间单调递减,但当掺杂掺杂超过0.100时就会发生淬灭。Ca_0.985Al₂Si₂O₈:0.01Eu³⁺的相对灵敏度随温度的升高先增大后减小,并在520 K时达到最大值（0.024 K^-1）。上述研究表明该荧光粉具备优异的温度传感性能,在测温领域具有广泛的应用前景。     

The effects of crystallization condition on the microstructure and thermal stability of istactic polypropylene nucleated by β‐form nucleating agent

This article deals with the crystallization behaviors of original (prepared in a torque rheometer), DSC crystallization and mold crystallization (quenching and slow nonisothermal crystallization) of isotactic polypropylene (iPP) mixed with β‐form nucleating agent. The microstructure and thermal stability of these samples were investigated. The wide angle X‐ray diffraction (WAXD) results indicate that fast cooling is favorable for β‐form iPP formation. With slower cooling rate and higher concentration of nucleating agent, the lamellar thickness and stability of crystal0s were enhanced. Polarized optical microscopy (POM) and scanning electron microscopy (SEM) both showed that rapid crystallized samples gave rise to tiny spherulites, whereas under slow crystallization condition, nucleated samples could be fully developed in the form of dendritic or transcrystalline structures, depending on the nucleating agent concentration. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Role of La2O3 in Pd-Supported Catalysts for Methanol Decomposition

Systems of Pd supported on various La₂O₃-modified -Al₂O₃ and CeO₂–Al₂O₃ catalysts were tested for catalytic methanol decomposition and characterized by means of XRD, BET, TPR, H₂-chemisorption and CO–FTIR. The addition of lanthanum significantly improved the selectivity of CO and H₂ for all the catalysts but showed a different influence on the catalytic activity in two systems. Methanol conversion decreased on La₂O₃-modified Pd/-Al₂O₃ catalysts, in line with the reduction of Pd dispersion, while the addition of La₂O₃ improved the dispersion of Pd and reinforced Pd–CeO₂ interaction for La₂O₃-modified Pd/CeO₂–Al₂O₃ catalysts, which resulted in a high production rate of CO and H₂. Thus, a synergistic effect between CeO₂ and La₂O₃ was observed on -Al₂O₃-supported Pd catalyst for methanol decomposition.     

Thermoelectric characterization of NaxMx/2Ti1−x/2O2 (M=Co, Ni and Fe) polycrystalline materials

Layered -titanate materials, Na_xM_x/2Ti_1−x/2O₂ (M=Co, Ni and Fe, x=0.2–0.4), were synthesized by flux reactions, and electrical properties of polycrystalline products were measured at 300–800 °C. After sintering at 1250 °C in Ar, all products show n-type thermoelectric behavior. The values of both d.c. conductivity and Seebeck coefficient of polycrystalline Na_0.4Ni_0.2Ti_0.8O₂ were ca. 7×10³ S/m and ca. −193 μV/K around 700 °C, respectively. The measured thermal conductivity of layered -titanate materials has lower value than conductive oxide materials. It was ca. 1.5 Wm⁻¹ K⁻¹ at 800 °C. The estimated thermoelectric figure-of-merit, Z, of Na_0.4Ni_0.2Ti_0.8O₂ and Na_0.4Co_0.2Ti_0.8O₂ was about 1.9×10⁻⁴ and 1.2×10⁻⁴ K⁻¹ around 700 °C, respectively.     

叔醋乳液的研制

以叔碳酸乙烯酯（VeoVa）为醋酸乙烯酯的共聚单体,聚乙烯醇为保护胶体,过硫酸铵（APS）为引发剂,当用SDS和OP-10为复合乳化剂,单体配比VeoVa：VAc为2：8,引发剂量为0．7％时,合成出的叔醋乳液吸水率最小;当用反应型乳化剂DNS-86,用量为3g时,其他配比不变,合成出的叔醋乳液吸水率最小。     

ZnxCd(1-x)S薄膜的制备及其光电性质的研究

用化学池沉积法制备了不同锌含量的 Znx Cd( 1 -x) S薄膜 ,并阐述了不同锌含量对薄膜性能的影响及其原因。通过 X射线衍射、扫描电镜、光谱透过率等测试方法表明 ,在 0 .4相似文献   

聚合物反胶团萃取氨基酸的研究

利用德国BASF公司生产的Pluronic型和PluronicR型两类嵌段聚合物制备聚合反应胶团萃取氨基酸（L－苯丙氨酸和L－异亮氨酸）， 聚合物反胶团对氨基酸的萃取平衡特性，实验表明，聚合物反胶团对氨基酸的萃取平衡时间与纯有机溶剂的物理萃取相比差别很小，溶质在反胶团外壳部分与其内部水池间的平衡分配系数K都普遍较大，另外，当氨基酸水溶液的PH值接近等电点时，反胶团萃取达到最佳效果。通过理论分析得到如下推断，聚合物反胶团对两亲性氨基酸的增溶主要在基外壳部分，很可能是包裹在聚氧丙烯外壳内或缠绕在聚氧丙烯链之间，亲油作用和氢键作用是聚合物反胶团萃取的主要推动力。