Synthesis of ［EMIM］Br-AlCl3 ionic liquid

采用N-甲基咪唑、溴乙烷、AlCl₃常规回流法以及微波法合成离子液体,研究［EMIM］Br中间体的产率;采用量子化学方法计算离子液体结构,明确合成反应的机理;通过紫外光谱和红外光谱表征［EMIM］Br-AlCl₃离子液体的结构;测试离子液体的密度、电导率等性质。结果表明：常规回流法以N-甲基咪唑和溴乙烷为原料,在70℃温度下反应5 h,反应产率为87.9%;微波法反应时间1000 s,产率为94.2%;40℃下密度为1.46 g·cm^-3,电导率为21 S·m^-1;用DFT B3LYP 量子化学计算方法研究离子液体的构型,离子液体的合成反应遵循SN2反应机理;紫外光谱和红外光谱表征了［EMIM］Br和AlCl₃/［EMIM］Br离子液体的结构。     

山楂叶中两个新黄酮

从山楂叶中分得２个新黄酮化合物,经过理化性质和光谱分析鉴定,命名为：Ｐｉｎｎａｔｉｆｉｄａ Ｃ和Ｐｉｎｎａｔｉｆｉｄａ Ｄ。     

蒙药鹅绒藤扫描电镜的观察研究

目的：为蒙药鹅绒藤药材鉴定研究提供地上部分表面的微形态依据。方法：采用扫描电子显微镜技术进行观察研究。结果：鹅绒藤叶片上下表皮、内外果皮、种子背腹面和花粉块的微形态各异。结论：为鹅绒藤药材微形态鉴定和生物学研究提供参考依据。     

Gallium bismuth halide GaBi-X2 (X = I,Br, Cl) monolayers with distorted hexagonal framework: Novel room-temperature quantum spin Hall insulators

Quantum spin Hall (QSH) insulators with a large topologically nontrivial bulk gap are crucial for future applications of the QSH effect.Among these,group Ⅲ-Ⅴ monolayers and their halides,which have a chair structure (regular hexagonal framework),have been widely studied.Using first-principles calculations,we formulate a new structure model for the functionalized group Ⅲ-Ⅴ monolayers,which consist of rectangular GaBi-X2 (X =I,Br,Cl) monolayers with a distorted hexagonal framework (DHF).These structures have a far lower energy than the GaBi-X2 monolayers with a chair structure.Remarkably,the DHF GaBi-X2 monolayers are all QSH insulators,which exhibit sizeable nontrivial band gaps ranging from 0.17 to 0.39 eV.The band gaps can be widely tuned by applying different spin-orbit coupling strengths,resulting in a distorted Dirac cone.     

溴系棉用阻燃剂的研究

本文合成了一系列溴系阻燃剂,探讨了溴系阻燃剂的阻燃机理;通过对结构相似的溴化物在棉纤维上阻燃效能的测定研究了溴含量对阻燃性的影响;用热分析方法从理论上分析了溴化物结构对其阻燃性能的决定作用;测定了溴-磷、溴-锑的协同效应;同时对阻燃剂TM—DABT的耐洗性及对染色的影响作了初步探讨。     

Europium and Acetate Co‐doping Strategy for Developing Stable and Efficient CsPbI2Br Perovskite Solar Cells

All‐inorganic perovskite solar cells have developed rapidly in the last two years due to their excellent thermal and light stability. However, low efficiency and moisture instability limit their future commercial application. The mixed‐halide inorganic CsPbI₂Br perovskite with a suitable bandgap offers a good balance between phase stability and light harvesting. However, high defect density and low carrier lifetime in CsPbI₂Br perovskites limit the open‐circuit voltage (V_oc < 1.2 V), short‐circuit current density (J_sc < 15 mA cm^?2), and fill factor (FF < 75%) of CsPbI₂Br perovskite solar cells, resulting in an efficiency below 14%. For the first time, a CsPbI₂Br perovskite is doped by Eu(Ac)₃ to obtain a high‐quality inorganic perovskite film with a low defect density and long carrier lifetime. A high efficiency of 15.25% (average efficiency of 14.88%), a respectable V_oc of 1.25 V, a reasonable J_sc of 15.44 mA cm^?2, and a high FF of 79.00% are realized for CsPbI₂Br solar cells. Moreover, the CsPbI₂Br solar cells with Eu(Ac)₃ doping demonstrate excellent air stability and maintain more than 80% of their initial power conversion efficiency (PCE) values after aging in air (relative humidity: 35–40%) for 30 days.     

Physico-chemical properties of WO3/TiO2 systems employed for 4-nitrophenol photodegradation in aqueous medium

A series of polycrystalline WO_x/TiO₂ samples were prepared by means of a conventional impregnation method. The samples were characterized by means of X-ray diffraction, Vis-UV diffuse reflectance and Raman spectroscopies, nitrogen adsorption at 77 K for determining specific surface areas and surface texture, scanning electron microscopy, and FT-IR monitoring of pyridine adsorption for measuring the surface acidity. Catalytic activity of the samples has been assessed by carrying out as a ``probe'' reaction the photodegradation of 4- nitrophenol in aqueous medium. The results obtained indicate that incorporation of tungsten on titania leads to formation of different surface species, depending on the tungsten loading. Tungsta microcrystals were detected by X-ray diffraction when the nominal molar W/Ti ratio reached a value of 8.0%. FT-IR investigation indicated that the presence of tungsten induces formation of Brønsted and Lewis surface acid sites. The photoactivity results confirm the beneficial effect of tungsten in TiO₂ for 4-nitrophenol photodegradation in aqueous medium. The reaction rates are higher than those reported in literature for another set of samples and maximum photoactivity was achieved for a sample containing 1.96 moles of W per 100 moles of Ti.     

Brφnsted酸性功能离子液体催化合成抗氧剂330

以吡啶和丁烷-1,4-磺酸内酯为原料,制备了4种B rφnsted酸性功能离子液体,并用于抗氧剂330:1,3,5-三甲基-2,4,6-三(3,5-二叔丁基-4-羟基苄基)苯的催化合成。系统考察了催化剂用量、反应温度、反应时间、催化剂重复使用对收率的影响。结果表明,在0℃,以CH2C l2为辅助溶剂,n([N-C4H8SO3HPyrid ine](HSO4-)∶n(1,3,5-三甲基苯)∶n(3,5-二叔丁基-4-羟基苄甲醚)=1∶3∶10,反应3 h,收率可达89.6%。     

室温离子液体的制备及物化性能研究

合成了[bm im]B r和[bm im]BF4室温离子液体,考察了其在不同溶剂中的溶解性能及导电性能,同时对离子液体在不同溶剂中的紫外吸收进行了测定。结果表明,离子液体在水、乙醇、乙酸、丙酮中可以较好的溶解,而在乙醚、苯、正己烷中不溶解;离子液体的电导率随浓度的增大和温度的升高而增大,在不同的溶剂中的电导率K不同,而且相差很大,其顺序为K(水作溶剂)>K(乙醇作溶剂)>K(乙酸作溶剂)。溶剂的极性对离子液体的紫外吸收影响较大,最大吸收波长的顺序为:λm ax(水为溶剂)<λm ax(乙醇为溶剂)<λm ax(乙酸为溶剂)。