木质素基二氧化硅复合纳米颗粒的制备及在高密度聚乙烯中的应用

针对目前木质素基SiO₂复合纳米颗粒聚集严重及木质素负载量低,难以应用的现状,以碱木质素为主要原料,先通过磷酸化改性制备磷酸化碱木质素,再利用酸析共沉法将1.2份磷酸化碱木质素与1份纳米SiO₂(均为质量份)复合制备了木质素-SiO₂复合纳米颗粒,并探究复合颗粒对高密度聚乙烯(HDPE)力学性能的影响。FT-IR、XPS、TEM、TG和静态接触角测试结果表明,木质素主要以氢键作用与SiO₂结合;与原料二氧化硅相比,复合颗粒的粒径从25 nm增加到40 nm,聚集程度明显减弱;复合纳米颗粒中木质素占47%(质量分数);表面的疏水性增强,有利于复合颗粒在高密度聚乙烯中均匀分散,显著提高了HDPE的拉伸强度。与碱木质素/HDPE复合材料相比,木质素-SiO₂复合纳米颗粒/HDPE复合材料的拉伸强度和断裂拉伸率分别提高了48.68%和73.57%。     

三芳基锗取代丙酸与乙氧基三氧杂氮杂硅杂三环[3,3,3,0~(15)]十一碳烷的反应

用 β-三芳基锗 -α(β) -取代丙酸与 1 -乙氧基 -2 ,8,9-三氧杂 -5 -氮杂 -1 -硅杂三环 [3 ,3 ,3 ,0 1 5]十一碳烷反应 ,合成了 1 2种含硅锗的双金属有机化合物。利用IR、NMR和MS表征了化合物的结构和裂解机制。生物活性测定表明 ,其杀菌活性具有一定的选择性     

Mn掺杂的ZnS纳米棒的制备及其高分子发光薄膜研究

本文利用溶剂热法制备了Mn掺杂的ZnS纳米线。探讨了Mn的掺杂量(5%,10%,15%)对ZnS纳米棒的尺寸、结构以及发光性能的影响,并且将所得到的纳米棒应用于聚合物环氧树脂(EP)中,制备了具有发光效应的高分子/纳米棒薄膜。X射线衍射(XRD)、扫描电镜(SEM)、能量色散光谱(EDS)进行纳米棒的形貌和组成进行了分析。荧光分析ZnS:Mn以及EP/ZnS:Mn发光性质。将ZnS:Mn纳米棒分散到环氧树脂中,在同一激发波长391 nm下,分散在EP/ZnS:Mn比ZnS:Mn纳米棒的荧光强度低,且发射波长发声蓝移。     

井口平台避让自升式钻井船分析

以渤海某井口平台为例,对自升式钻井船在井口平台上的避让进行了分析。根据拟定钻井船的参数,以及作业水深、井口平台设计参数等,对钻井船就位、避让进行了放样。并在发生碰撞时,提出了解决碰撞的方案,以最小的设计改动满足了避让钻井船的要求。     

煤制烯烃企业全厂能量系统优化策略及应用

为了实现煤制烯烃企业全厂能量系统优化,提出了煤制烯烃企业全厂能量系统基于单元、子系统和全局划分的渐进协同优化策略,包括全厂用能状况分析、工艺装置用能及换热网络优化、低品位热回收和优化利用、全厂蒸汽动力系统优化等步骤。应用上述优化策略,对某60万t/a煤制烯烃企业全厂能量系统优化进行研究,得到全厂各单元能耗分布,提出了甲醇合成和甲醇制烯烃单元换热网络优化、全厂蒸汽动力系统降低蒸汽减温减压量及低品位热合理匹配利用等节能方案,理论上可以提高全厂系统能效3%以上,年节约标煤10万t以上,投资回收期小于1 a。     

实践教学在发酵工程课程中的应用

发酵工程是生物工程、生物技术、食品工程等专业的一门重要专业课程。文章主要探讨了如何在发酵工程课程中,将理论教学和实践教学内容相结合、实践教学内容的实现模式,以及教学效果的评估等内容。通过在发酵工程课程强化实践教学的应用,激发了学生的学习兴趣,提高了教学质量。     

木质素磺酸钠在TiO2/水界面的吸附特性

木质素磺酸钠在固体表面的吸附特性决定了其应用性能,利用红外和紫外分光光度仪,采用剩余质量分数法研究了温度、pH值、无机盐和氢键破坏剂脲对木质素磺酸钠在TiO₂/水界面吸附动力学和等温吸附性能的影响,初步探讨了其在固液界面的吸附作用机理。结果表明,该吸附为单层多点式吸附,随着温度升高和pH值减小,木质素磺酸钠在TiO₂/水界面的吸附速率常数和饱和吸附量均增大,而离子强度的增大和脲的加入却使吸附速率常数减小;木质素磺酸钠在TiO₂/水界面的吸附驱动力为静电、疏水和氢键作用,疏水作用力可显著增加其吸附量。     

Phase Transfer Catalysis with Quaternary Ammonium Type Gemini Surfactants: <Emphasis Type="Italic">O</Emphasis>-Alkylation of Isovanillin

In this paper, O-alkylation of isovanillin with unusual phase transfer catalysts alkandiyl-α,ω-bis(dimethylalkylammonium bromide) dimeric surfactants (also known as gemini surfactants) is described. Some dimeric surfactants with simple hydrophobic alkyl chains and others with hydrophobic alkyl chains containing ester functionalities with different lengths were synthesized and characterized in our laboratory. The alkylation of isovanillin with alkyl halide was successively carried out in the presence of potassium carbonate and a phase transfer catalyst in tetrahydrofuran. The same reactions were also performed with both the traditional phase transfer catalyst tetrabutylammonium bromide and without any catalyst. The results were compared with those of dimeric surfactants. Consequently, it was expressed that alkandiyl-α,ω-bis(dimethylalkylammonium bromide) dimeric surfactants successively exhibit the character of phase transfer catalysts through environmentally friendly procedures under mild conditions. The most significant feature of this work is that dimeric surfactants have been determined to act as phase transfer agents.     

Photocrosslinked biobased phase change material for thermal energy storage

A series of novel photocrosslinked biobased shape‐stabilized phase change materials (PCMs) based on octadecanol, eicosanol and docosanol have been prepared by UV technique for the purpose of thermal energy storage applications. Epoxidized soybean oil was reacted with acrylic acid to form acrylated soybean oil (ASO). The structure and composition, cross‐section morphology, thermal stability performances and phase change behaviors of ASO and UV‐cured PCMs were examined by using Attenuated total reflection fourier transform infrared spectroscopy, thermogravimetric analysis system (TGA), scanning electron microscopy, and differential scanning calorimetry. The results indicate that the UV‐cured biobased PCMs possess perfect phase change properties and a suitable working temperature range. The heating process phase change enthalpy is measured between 30 and 68 J/g, and the freezing process phase change enthalpy is found between 18 and 70 J/g. The decomposition of UV‐cured PCMs started at 260 °C and reached a maximum of 430 °C. All the biobased UV‐cured PCMs improved latent heat storage capacity in comparison with the pristine ASO sample. With the obtained results we conclude that, these materials promise a great potential in thermal energy storage applications. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43757.