L-Proline as an efficient and reusable promoter for the synthesis of coumarins in ionic liquid

The effect of L-proline as a promoter on the condensation reaction of salicylaldehyde or its derivatives with ethyl acetoacetate in neutral ionic liquid [emim]BF4 was studied. All reactions were carried out under mild reaction conditions and achieved high yields. Moreover, the ionic liquid containing L-proline could be recycled and reused for several times without noticeably decreasing in productivity. The results show that the L-proline-[emim]BF4 system has a potential in contribution to the development of environmentally friendly and inexpensive processes in organic syntheses.     

Lithium secondary batteries using an asymmetric sulfonium-based room temperature ionic liquid as a potential electrolyte

A new asymmetric sulfonium-based ionic liquid, 1-butyldimethylsulfonium bis（trifluoromethylsulfonyl） imide （S114TFSI）, was developed as electrolyte material for lithium secondary battery. Its cathodic potential was a little more positive against the Li/Li＋, so vinylene carbonate （VC） was added into the LiTFSI/S114TFSI ionic liquid electrolyte to ensure the formation of a solid electrolyte interface （SEI）, which effectively prevented the decomposition of the electrolyte. The properties of the Li/LiMn2O4 cell containing S114TFSI-based electrolyte were studied and the cycle performances were compared to those with a conventional organic electrolyte （1 mol/L LiPF6/DMC：EC=1：1（w/w）） at room temperature. Electrochemical impedance spectroscopy （EIS） and X-ray diffraction （XRD） were conducted to analyze the mechanisms affecting the cell performances at different temperatures. The lithium secondary bat- tery system, using the above ionic liquid electrolyte material, shows good cycle performances and good safety at room temperature, and is worthwhile to further investigate so as to find out the potential application.     

钢基底上预镀中间层沉积金刚石膜

利用表面预镀中间层在４５号钢上化学气相沉积（ＣＶＤ）得到了金刚石膜。钢基底表面金刚石涂层具有许多潜在应用价值，但直接在钢上沉积生长金刚石面临长的形核期，铁原子的触媒作用和热膨胀不匹配等严重问题。文中采用钢基底表面预镀中间层的方法，阻止碳向基底中扩散，增强膜基结合和抑制ＳＰ２杂化碳的沉积。分别研究了直接在钢基底上、表面预镀铜膜和表面预镀硅膜钢基底上热丝法沉积金刚石膜的工艺特点。通过ＳＥＭ、Ｒａｍａｎ谱和划痕法检验表明，钢基底表面预镀硅膜作为中间层，是一种在钢上沉积金刚石膜的有效方法。     

Nanoscale electropolishing of high-purity nickel with an ionic liquid

High purity(99.9% composition) nickel metal specimens were used in electropolishing treatments with an acid-free ionic liquid electrolyte prepared from quaternary ammonium salts as a green polishing solution. Voltammetry and chronoamperometry tests were conducted to determine the optimum conditions for electrochemical polishing. Atomic force microscopy(AFM) revealed nanoscale effectiveness of each polishing treatment. Atomic force microscopy provided an overall observation of the material interface between the treated and unpolished regions. Surface morphology comparisons summarized electrochemical polishing efficiency by providing root-mean-square roughness averages before and after electrochemical polishing to reveal a mirror finish six times smoother than the same nickel metal surface prior to electropolishing. This transition manifested in a marked change in root-mean-squared roughness from 112.58 nm to 18.64 nm and producing a smooth mirror finish. Finally, the mechanism of the ionic liquid during electropolishing revealed decomposition of choline in the form of a transient choline radical by acceptance of an electron from the nickel-working electrode to decompose to trimethylamine and ethanol.     

Raman光谱对离子液体及其可支撑离子液体膜的表征

利用Raman及其表面增强Raman光谱对不同阴离子的3种丁基咪唑离子液体及其负载膜的结构进行测定分析表征.结果表明:3种离子液体其[C4mim]+阳离子结构非常相近,受不同阴离子的影响较小.在室温常压下阳离子[C4mim]+同时存在偏移和扭转两种同分异构体.相比于亲水性支撑离子液体膜,疏水性PVDF可支撑离子液体膜的普通Raman难以测定,采用以银溶胶作为表面增强活性基底的表面增强Raman与亲水性可支撑离子液体膜的普通Raman,以及纯离子液体的普通Raman高度一致,充分显示出表面增强Raman光谱对支撑离子液体膜结构表征的适用性及优越性,为今后在离子液体膜方面的Raman研究开启了新的方向.     

Characteristic mechanical properties and complex ordered structures in metal films on liquid substrates

It is well known that the nature of the substrate plays a significant role in the growth mechanism, micro- structure, surface morphology and physical property of thin film systems. Because the metal film systems de- posited on solid substrates generally p…     

硫酸氢根吡啶催化制备乙酸正丁酯的酯化反应精馏过程模拟

采用离子液体硫酸氢根吡啶（[Hpy][HSO4]）作为催化剂,对乙酸和正丁醇在反应精馏塔中进行酯化反应生成乙酸正丁酯的过程进行模拟研究。在缺乏实验数据的情况下,使用真实溶剂似导体屏蔽模型(COSMO-RS)方法预测了离子液体与其他物质的汽液相平衡,得到了离子液体与反应体系的二元交互参数。基于共沸精馏概念设计了带有分相器的反应精馏塔,实现了离子液体的循环利用。分析了反应精馏塔总塔板数、进料模式、进料塔板位置、再沸器热值和塔板持液量对于产品质量和乙酸转化率的影响,结果表明,当反应精馏塔塔板总数为28,反应物从第4块塔板同时进料,离子液体从第2块塔板进料,且塔板持液量为0.05m3时,乙酸正丁酯纯度和乙酸转化率均可达99.9%。     

离子液体-有机液体混合体系中制备NiO电致变色薄膜的结构和性能

采用电化学沉积方法在NiCl_2、离子液体和有机液体(DMF)混合体系中制备出结构和性能优异的NiO电致变色薄膜。采用SEM、XRD、紫外-可见分光光度仪、电化学工作站对薄膜的形貌、物相、光学及电化学等方面进行了研究。通过对沉积电位和时间的控制,实现了对薄膜厚度和微结构的控制。结果表明,在室温下,在沉积电位为3.0 V,沉积时间30 s的条件下,所得到的NiO薄膜具有最佳光学性能,其消/着色态透光率差值达到52.7%。在沉积电位3.9 V,沉积时间20 s条件下,薄膜具有最快的响应时间(t_b/t_c=0.32 s/0.30 s)。     

多库酯类离子液体作为基础油添加剂对镁合金的润滑性能研究

目的 将5种多库酯类离子液体作为非极性基础油液体石蜡(LP)和极性基础油聚乙二醇(PEG400)的添加剂,研究其作为钢/镁合金摩擦副润滑剂的摩擦学性能,并分析润滑作用机理.方法采用离子交换法合成离子液体添加剂,并利用SRV-V微动振动摩擦磨损试验机、三维表面轮廓仪考察其摩擦学性能,采用X射线光电子能谱仪、扫描电子显微镜和石英晶体微天平对润滑作用机制进行探究.结果 5种多库酯类离子液体作为添加剂具有良好的减摩抗磨性能;添加量为1% 可以有效改善基础油LP的摩擦学性能,而离子液体作为基础油PEG400添加剂在3% 含量可以起到一定的减摩抗磨效果;XPS结果表明在摩擦过程中润滑剂与镁合金表面发生了摩擦化学反应,形成了MgO ,Mg3 (PO4 )2和MgSO4等物质的摩擦化学反应膜.结论 多库酯类离子液体作为非极性基础油LP和极性基础油PEG400的添加剂,均可以改善其对钢/镁合金摩擦副的润滑性能,且物理吸附膜和摩擦化学反应膜共同决定了其润滑性能.     

Biomorphic analysis as a basis for paleoenvironmental reconstruction

A definition for biomorphic analysis is suggested. The objects of analysis - biomorphs (phytoliths, sponge spicules) - are characterized with respect to their diagnostic features and methods of data interpretation. The possibility of to include studies into the general system of paleoenvironmental and palaeosols interpretations from biomorphic analysis is substantiated with concrete examples.     

表面自由基链转移反应制备润湿性可控聚合离子液体薄膜

采用分子自组装技术在羟基化的单晶硅表面制备了3-巯丙基三甲氧基硅烷单分子层,然后以偶氮二异丁腈为引发剂,通过表面自由基链转移反应在基底表面引发了离子液体单体1-烯丙基-3-甲基咪唑氯化物([AMIM]Cl)的原位聚合,通过直接离子交换法改变了薄膜表面的对阴离子.用X射线光电子能谱仪(XPS)分析了聚合物薄膜表面典型元素的化学状态,用原子力显微镜(AFM)观察了薄膜的表面形貌,用椭圆偏光仪测量了薄膜的厚度,并用接触角仪对薄膜表面的静态水接触角进行了测量.结果表明,聚合离子液体薄膜成功接枝到了硅片表面,通过对离子的交换实现了薄膜表面润湿性的可控转变.     

泡沫陶瓷过滤片通过金属液能力的模拟研究

借助于水模拟的方法，研究了浇注压头、泡沫陶瓷过滤片的有效面积、厚　　　度及结构参数对金属液通过能力的影响。提出型内过滤流量系数ｃ及流量公　　　　式Ｑ＝Ｆ浇·（μ＋ｃ）过滤流量系数反映了滤片结构及冶因素。　　　　对滤片通过能力的影响。在有效过滤时间内，用无渣水模拟体系代替有渣模　　　拟体系是一种简便可行的试验研究方法。     

铝箔腐蚀中咪唑衍生物离子液体的缓蚀作用研究

文章采用自制的咪唑衍生物离子液体为缓蚀剂,结合典型生产工艺,研究了合成缓蚀剂在铝箔腐蚀中的作用.实验结果表明,温度、硫酸浓度和离子液体浓度对铝箔腐蚀有重要的影响.随硫酸浓度加大,腐蚀速率存在先减小后加大的现象,表面稀硫酸对该缓蚀剂有协同增强效应,离子液体浓度较小时,缓蚀效率变化明显.高温时离子液体缓蚀剂仍呈现出良好的缓蚀性能,离子液体在铝箔上吸附符合Langmuir公式, 文中对腐蚀作用机制进行了探讨,分析结果与实验测量值相吻合.     

Force optimization of ionic polymer metal composite actuators by an orthogonal array method

Ionic polymer metal composites (IPMCs), a new kind of electro-active polymer, can be used for micro robotic actuators, artificial muscles and dynamic sensors. However, IPMC actuators have the major drawbacks of a low generative blocking force and dependence on a humid environment, which limit their further application. Multiple process parameters for the fabrication of IPMCs were optimized to produce a maximum blocking force; the parameters included reducing agent concentration, platinum salt concentration in the initial compositing process, and tetraethyl orthosilicate (TEOS) content. An orthogonal array method was designed and a series of fabrication experiments were carried out to identify the optimum process parameters. The results show that the platinum salt concentration in the initial compositing process plays the most significant role in improving the blocking force of IPMCs, the TEOS content plays an important role, and the reducing agent concentration has no apparent effect on the blocking force. In the optimized conditions, the IPMC actuator exhibited maximum blocking force of 50 mN, and the corresponding displacement was 14 mm. Compared with normal conditions, the blocking force improved 2.4-fold without sacrificing the displacement, and the effective air-operating life was prolonged 5.8-fold for the blocking force and 5-fold for the displacement. This study lays a solid foundation for further applications of IPMCs.     

Electrodeposition of Al from a 1-butylpyrrolidine-AlCl3 ionic liquid

The addition of 1-butylpyrrolidine to AlCl_3 results in the formation of an electrolyte that is suited to Al deposition.The feasibility of electrodepositing Al from the synthesized electrolyte was investigated.Several compositions of AlCl_3 and 1-butylpyrrolidine were prepared for this purpose.These mixtures show a different phase behavior at various compositions of AlCl_3 and 1-butylpyrrolidine.IR,Raman and NMR spectroscopy were employed to characterize the synthesized liquids.Among the prepared compositions,1:1.2 mol ratio of 1-butylpyrrolidine:AlCl_3 and the upper phase of 1:1.3 mol ratio of 1-butylpyrrolidine:AlCl_3 were found to be suitable for Al electrodeposition at room temperature(RT).Uniform and thick( mm thick) layers of Al were obtained on copper at RT.Al deposition occured from the cationic species of AlCl_3 xLty(where x r 2,y ? 1–2,and L ? 1-butylpyrrolidine) in this electrolyte.This behavior is contrary to the well investigated classic AlCl_3 based ionic liquids,where the deposition of Al occurs mainly from anionic Al2 Cl 7ions.     

以离子液体为模板剂合成Cr-MCM-41及其催化性能

制备离子液体1-十六烷基-3-甲基咪唑四氟硼酸盐([C16mim]BF4),并以此为模板剂合成掺杂Cr的介孔分子筛Cr-MCM-41。采用X线衍射仪(XRD)、N2吸附-脱附仪、透射电子显微镜(TEM)和傅里叶红外光谱仪(FT-IR)对Cr-MCM-41进行表征,并将Cr-MCM-41应用于H2O2氧化乙苯反应中,考察其催化性能。结果表明:合成的分子筛具有介孔结构,随着Cr掺入量的增加出现Cr2O3晶相。当反应温度为60℃、乙苯0.04 mol、H2O20.12mol、Cr-MCM-41-2 0.1 g,反应时间10 h,乙苯转化率达12.40%,选择性达100%。     

磺酸型双核离子液体催化合成聚丁二酸丁二醇酯

采用四步法合成一种新型功能化双核磺酸类咪唑离子液体,并考察其在催化丁二酸与丁二醇缩聚合成聚丁二酸丁二醇酯(PBS)的性能。用红外光谱仪(FT-IR)和核磁共振仪(1H NMR)对双核离子液体催化剂及PBS进行表征,考察催化剂用量、反应时间、反应温度对PBS黏均相对分子质量的影响。结果表明:当m(催化剂)∶m(丁二酸)=1∶40,反应温度230℃,反应5 h,PBS的黏均相对分子质量达到最高值8.1×104,熔点为113～119℃。