新型的α-二亚胺Ni(Ⅱ)配合物的合成及催化乙烯聚合研究

设计并合成了一种新型的含有大体积基团phenyl的α-二亚胺配体1a及其Ni(Ⅱ)配合物1b,采用NMR谱、XPS对其进行了表征。研究了聚合条件如Al/Ni摩尔比、聚合反应温度及配体结构等因素对催化剂活性的影响。在反应温度为5℃,Al/Ni摩尔比为800时,该催化体系催化乙烯聚合的活性最高,可达5.57×106g PE/(molNi·h·bar),所得聚乙烯具有较高的支化度,最高可达136 branches/1000C。采用1H NMR、DSC、GPC、TG分别对聚合物进行了表征。     

Ti-6.5Al-3.5Mo-1.5Zr-0.3Si合金中α′相和α″相的组织演变与力学性能

对Ti-6.5Al-3.5Mo-1.5Zr-0.3Si合金进行固溶时效处理,随后使用光学显微镜、扫描电镜、XRD衍射仪、拉伸试验以及冲击性能试验,分析固溶时效对合金中α′相和α″相的组织演变与力学性能的影响。结果表明,固溶处理后的微观组织中发生初生α相尺寸变小并趋于等轴化,尺寸较小的初生α相发生溶解并消失,其β转变组织变得不明显,经时效后的微观组织中析出大量α_s相,β转变组织更加明显。经固溶处理后,组织均由α+α′+α″相构成,经时效处理后,组织由α相和β相构成。合金经固溶处理后,其抗拉强度为1336 MPa,屈服强度为1070 MPa,断后伸长率为6%,断面收缩率为22%,冲击吸收能量为16 J。经时效处理后,强度随时效温度升高而升高,塑性趋势与之相反,其冲击性能几乎没有变化。合金经固溶处理后的拉伸与冲击断口微观形貌均由韧窝构成,为典型的韧性断裂。经时效处理后,拉伸和冲击断口的微观形貌有明显的高低起伏,随着时效温度的升高,韧窝的尺寸和数量减少,并出现撕裂棱以及空洞,断裂类型有向脆性断裂转变的趋势,但仍以韧性断裂为主。     

9α-氟-6α-甲基氢化泼尼松的合成研究

以6α-甲基氢化泼尼松为起始原料,经酯化、脱水、溴化、环合、二次酯化、加成6步反应合成了目标化合物9α-氟-6α-甲基氢化泼尼松,总收率13%。该合成路线反应步骤较少,反应条件温和,操作简单,对工业生产具有较好的参考价值。     

α-萘氧乙酸的合成研究

根据Williamson原理,在碱性条件下以α-萘酚、氯乙酸等为原料制得了α-萘氧乙酸。其结构经熔点（m.p.）、红外光谱（IR）、元素分析等手段得以确认。反应过程考察了各种条件对产率的影响。     

Synthesis of imidazo[2,1-b]thiazoles through the reaction of thiohydantoins and α-bromoketones

Imidazo-fused heterocycles are used as anticancer agents. In this study, some novel imidazo[2,1-b]thiazoles were synthesized from thiohydantoins and α-bromoketones in good yields. This method has the advantages of simple operation, high yields, and mild reaction conditions and uses less toxic and low-cost chemical reagents.     

高性能电瓷材料配方的研究

为了满足生产550kV/20kN以上棒形产品的要求,对高性能电瓷材料配方进行了研究,在配方中添加α-Al2O3,可提高电瓷材料强度;添加碱土金属元素化合物,可起到强熔剂与“压碱效应”的作用。研制出的等静压电瓷材料具有较低的烧成温度和良好的机、电、热性能;瓷弯曲强度184MPa、瓷上釉弯曲强度230MPa、电气强度32kV/mm、冷热急变性200K。     

Removal of bisphenol A and 17α-ethinyl estradiol from landfill leachate using single-walled carbon nanotubes

In this study, the adsorption of bisphenol A (BPA) and 17α-ethinyl estradiol (EE2) from landfill leachate onto single-walled carbon nanotubes (SWCNTs) was investigated. Different leachate solutions were prepared by altering the pH, ionic strength, and dissolved organic carbon (DOC) in the solutions to mimic the varying water conditions that occur in leachate during the various stages of waste decomposition. The youngest and oldest leachate solutions contained varying DOC and background chemistry and were represented by leachate Type A (pH = 5.0; DOC = 2500 mg/L; conductivity = 12,500 μS/cm; [Ca²⁺] = 1200 mg/L; [Mg²⁺] = 470 mg/L) and Type E (pH = 7.5; DOC = 250 mg/L; conductivity = 3250 μS/cm; [Ca²⁺] = 60 mg/L; [Mg²⁺] = 180 mg/L). These solutions were subsequently combined in different ratios to produce intermediate solutions, labeled B-D, to replicate time-dependent changes in leachate composition. Overall, a larger fraction of EE2 was removed as compared to BPA, consistent with its higher log K_OW value. The total removal of BPA and EE2 decreased in older leachate solutions, with the adsorptive capacity of SWCNTs decreasing in the order of leachate Type A > Type B > Type C > Type D > Type E. An increase in the pH from 3.5 to 11 decreased the adsorption of BPA by 22% in young leachate and by 10% in old leachate. The changes in pH did not affect the adsorption of EE2 in the young leachate, but did reduce adsorption by 32% in the old leachate. Adjusting the ionic strength using Na⁺ did not significantly impact adsorption, while increasing the concentration of Ca²⁺ resulted in a 12% increase in the adsorption of BPA and a 19% increase in the adsorption of EE2. DOC was revealed to be the most influential parameter in this study. In the presence of hydrophilic DOC, represented by glucose in this study, adsorption of the endocrine disrupting compounds (EDCs) onto the SWCNTs was not affected. In the absence of SWCNTs, hydrophobic DOC (i.e., humic acid) adsorbed 15-20% of BPA and EE2. However, when the humic acid and SWCNTs were both present, the overall adsorptive capacity of the SWCNTs was reduced. Hydrophobic (π-π electron donor-acceptor) interactions between the EDCs and the constituents in the leachate, as well as interactions between the SWCNTs and the EDCs, are proposed as potential adsorption mechanisms for BPA and EE2 onto SWCNTs.     

负载型铜在萘的α-硝基化反应中的催化性能

目前工业上合成 α-硝基萘仍然采用传统的混酸硝化法,然而该方法存在区域选择性不高、官能团耐受性差、产生过量酸性废液以及后处理费用高等诸多局限性,导致环境污染以及生产成本的提高,不符合绿色化学的理念。鉴于 α-硝基萘的应用前景,本文通过浸渍-焙烧-还原等步骤设计合成一系列负载型铜催化剂,实现了萘向 α-硝基萘的高效、经济、绿色的催化转化。其中,以ZSM-5等为载体合成的催化剂Cu/ZSM-5催化效果最好,以较高的分离产率（高达95%）和优异的区域选择性[(α-∶β-)>(98∶2)]得到了目标产物α-硝基萘,而且在重复使用4次后依然保持较高的催化活性和结构稳定性。     

局部磨损对α型旋风分离器内流场及分离性能的影响

以α型旋风分离器为研究对象,基于欧拉-拉格朗日方法,采用雷诺应力模型（RSM）、颗粒离散相模型（DPM）、E/CRC磨损方程对分离器内流场与磨损特性进行数值模拟。通过分析速度矢量、切向速度、颗粒运动轨迹等参数的分布规律,研究了局部磨损对设备内流场及分离性能的影响。结果表明,α型旋风分离器入口正对壁面磨损最为严重,最大磨损率约为1.4×10^-5kg/(m²·s)。磨损引起壁面几何结构的改变,导致气流方向发生偏转,不利于主流的稳定与固体颗粒的分离。随局部磨损的加剧,排气管下口短路流急剧增大,从而导致排气管下口以下区域流体流量减少,外涡切向速度降低;细颗粒的逃逸现象更加明显,粗颗粒运动轨迹趋于重合,更易形成高浓度灰环加剧壁面磨损。与未磨损时相比,局部磨损厚度50mm时,3μm粒径颗粒的分离效率由74.38%降低至54.97%,分割粒径d₅₀由0.73μm增大至2.36μm;设备压降降低了约15.41%。     

三元复合烧结助剂Er2O3-Mg2Si-Yb2O3对氮化硅陶瓷性能的影响

以Er₂O₃-Mg₂Si-Yb₂O₃为三元复合烧结助剂,制备了力学性能优异的高导热氮化硅陶瓷,研究了Er₂O₃-Mg₂Si-Yb₂O₃体系对氮化硅陶瓷致密化、微观结构、力学性能、热导率的影响。研究表明,当添加5%(质量分数,下同)Er₂O₃+2%Mg₂Si+4%Yb₂O₃烧结助剂时,烧结助剂对氮化硅陶瓷致密度与晶界相含量的平衡效果最佳,此时氮化硅陶瓷具有最佳性能:抗弯强度为765 MPa,断裂韧性为7.2 MPa·m^1/2,热导率为67 W/(m·K)。在烧结过程中,只添加5%Er₂O₃+2%Mg₂Si的烧结助剂产生的液相量少且黏度高,不能使氮化硅陶瓷完成致密化;此外,当添加的Yb₂O₃含量超过4%时,烧结助剂产生大量的晶界相,降低了氮化硅陶瓷的性能。