B酸离子液体催化棉籽油酯交换制备生物柴油

制备了5种对水稳定性好、带—SO3H官能团的磺酸类B酸离子液体,并以它们作催化剂进行了棉籽油酯交换反应制备生物柴油的研究。实验结果表明,这些磺酸类B酸离子液体的催化活性高,它们的催化活性与含氮官能团的种类和碳链长度有关,其中,吡啶丁烷磺酸硫酸氢盐离子液体的催化活性最高。考察了吡啶丁烷磺酸硫酸氢盐离子液体的用量、醇与油摩尔比、反应温度对酯交换反应的影响及离子液体的稳定性,实验结果表明,在反应温度170℃、n(甲醇)∶n(棉籽油)∶n(离子液体)=12∶1∶0.057、反应时间5h的条件下,产物中脂肪酸甲酯的质量分数可达92.0%,且离子液体的稳定性好,可循环使用。     

STUDY ON A CATALYTIC DISTILLATION COLUMN WITH A NOVEL INTERNAL

A novel internal for holding a catalyst in a catalytic distillation column was studied and its feasibility was verified by a model reaction, which is the alkylation of benzene with propylene over Hβ zeolite catalyst. The novel internal enlarges the void of the catalyst bed and provides the gas and liquid flow channels. It was proved that the catalytic distillation column with the novel internal has such advantages as simple structure, low operating cost, convenience for loading and unloading catalyst, and large catalyst loading fraction. It was found that the operational capability of the column with the novel internal whose volume fraction is about 30% is similar to that of a column filled with catalysts mixed with Cannon rings whose volume fraction is about 80%. It was also found that compared with the fixed-bed bubble reactor, the selectivity of cumene and the conversion of benzene are significantly improved in the CD (Catalytic Distillation) column with the internal.     

一步法合成二亚磷酸三(2,2'-联苯酚)酯

以三氯化磷和2,2'-联苯酚为原料,一步法合成了二亚磷酸三(2,2'-联苯酚)酯,通过质谱及核磁共振等方法对产品进行了表征,证实产品为目标化合物且纯度很高。考察了三乙胺用量、溶剂种类、反应时间以及反应温度等因素对产品收率的影响。最佳反应条件为:以氯仿为溶剂,n(三氯化磷)∶n(2,2'-联苯酚)∶n(三乙胺)=1∶1.5∶3.5,25℃下反应15 h。在此条件下制得的产品为白色晶体,收率为89.7%。对可能发生的副反应进行了探讨,当反应程度过低时,会生成含氯的副产物;而当反应过于剧烈时,生成三亚磷酸酯等副产物的几率增大。     

无人机高分辨率航拍影像在水土保持中的应用

采用无人机遥感测量和全方位航拍,可以短时、高效、清晰、准确把握工程各项水土保持措施实施情况和水土流失防治效果,同时通过使用无人机等先进技术可以快速、准确地获得区域土壤侵蚀及其防治状况,并且可以全面调查弃渣场等重要水土保持设施的措施布设、运行情况,排查周边是否存在敏感性制约因素,分析是否存在水土流失安全隐患等,为水土保持宏观规划和制定防治政策提供决策依据。结合工作经验通过介绍无人机影像处理、数据矢量化以及无人机在水土工作中的应用,对水土保持工作具有一定的实践指导作用。     

High‐Performance Fluorescent Organic Light‐Emitting Diodes Utilizing an Asymmetric Anthracene Derivative as an Electron‐Transporting Material

Fluorescent organic light‐emitting diodes with thermally activated delayed fluorescent sensitizers (TSF‐OLEDs) have aroused wide attention, the power efficiencies of which, however, are limited by the mutual exclusion of high electron‐transport mobility and large triplet energy of electron‐transporting materials (ETMs). Here, an asymmetric anthracene derivative with electronic properties manipulated by different side groups is developed as an ETM to promote TSF‐OLED performances. Multiple intermolecular interactions are observed, leading to a kind of “cable‐like packing” in the crystal and favoring the simultaneous realization of high electron‐transporting mobility and good exciton‐confinement ability, albeit the low triplet energy of the ETM. The optimized TSF‐OLEDs exhibit a record‐high maximum external quantum efficiency/power efficiency of 24.6%/76.0 lm W^?1, which remain 23.8%/69.0 lm W^?1 at a high luminance of even 5000 cd m^?2 with an extremely low operation voltage of 3.14 V. This work opens a new paradigm for designing ETMs and also paves the way toward practical application of TSF‐OLEDs.     

共沉淀法制备Al（OH）3-Y（OH）3/ZrB2复合粉体的热力学形成条件研究

由于ZrB2的独特晶体结构,使其兼有金属和陶瓷的许多优异的物理和化学性能,因此在许多领域得到广泛应用。本文利用共沉淀法制备A1(OH)3-Y(OH)3/ZrB2复合粉体,并研究其形成热力学条件。经过热力学计算并用实验验证得出:ZrB2悬浮液的pH值必须大于8.3,才符合Al3+与Y3+共沉淀所需热力学条件;当ZrB2悬浮液的pH值为9时,A1(OH)3-Y(OH)3/ZrB2复合粉体的壳-核结构最好。在溶液浓度较低的情况下,可以获得具有理想壳-核结构的A1(OH)3-Y(OH)3/ZrB2复合粉体,即c(Al3+)=0.017mol/L,c(Y3+)=0.010mol/L,分别接近于Al(NO3)3和Y(NO3)3浓度的热力学条件计算拟定值,即:0.012 60mol/L和0.007 56mol/L。     

粉末高温合金中夹杂物特性及与不同成型工艺的关系

全面研究了FGH95粉末高温合金原始粉末和粉末处理过程中夹杂物的性质(成分、分类和形貌),分析了其数量和来源,研究了夹杂物在不同成型工艺下的变形特征,讨论了解决夹杂物问题的方法.     

高铁不同刚度桩-网复合地基工作性状差异

结合沪宁城际铁路CFG桩网复合地基试验段和京沪高铁砂桩网复合地基昆山试验段,在现场试验断面埋置土压力盒、沉降计和孔隙水压计等监测仪器,获取地基沉降、桩和桩间土压力、孔隙水压等监测数据,对比分析CFG桩与砂桩网在高速铁路地基工作性状及工后沉降控制效果中的差异。分析结果表明:CFG桩网和砂桩网联合堆载预压均可满足高速铁路无砟轨道工后沉降控制要求,CFG桩网复合地基沉降总量与沉降速率均小于砂桩网复合地基,且收敛速度快;受桩刚度差异的影响,CFG桩网复合地基与砂桩网复合地基桩土应力规律存在较大差异,前者桩土应力比随着路堤填筑加载而增大,最终趋于稳定,后者桩土应力比随荷载增加先增大后减小,再增大,呈波浪形变化;CFG桩网地基超孔压消散速率远小于砂桩桩网地基的超孔压消散速率;在施工工期较短的情况下,与砂桩网复合地基相比,CFG桩网复合地基处理技术的工后沉降控制效果更优。     

基于加权颜色分层和纹理单元的图像检索算法

针对仅使用单一颜色或纹理特征并不能达到较好的图像检索效果的问题,提出了一种结合颜色和纹理特征的图像检索算法。首先,颜色微观部分利用颜色直方图,刻画每种颜色的像素占整个图像的比例;然后,宏观部分应用颜色熵和位平面熵分别对图像处理,其中位平面熵取特征较明显的前4层,并对每层的位平面熵加权;最后,根据定义的五种基本纹理结构基元中各像素点的颜色值和角度值,结合颜色特征,实现图像检索。实验结果表明,加权位平面熵和不加权位平面熵比较,在Corel-1000数据集上平均查准率和平均查全率分别提高10.01个百分点和1.2个百分点。结合颜色和纹理特征的图像检索算法与仅表现纹理特征的结构元素描述(SED)方法相比,在Corel-10000数据集上平均查准率和平均查全率分别提高4.3个百分点和2.1个百分点,有效地提高了图像检索效果。     

酸性染料低温毛皮染色研究

通过酸性黑１０Ｂ染毛皮，采用低温染色技术，即氨水－纯碱法，尿素－亚硫酸氢钠法等，使染色温度有明显降低，从而表明酸性染料低温染色技术用于毛皮上是可行。