钼磷酸铵及钼磷酸掺杂的聚合物电解质

以聚氧乙烯(PEO)为基质,掺杂适量的钼磷酸铵或钼磷酸,制备出PEO-(NH₄)₃PMo12O₄₀及PEO-H₃PMo12O₄₀质子导电聚合物电解质膜,测定了其电导率.讨论了加入(NH₄)₃PMo12O₄₀及H₃PMo12O₄₀对PEO构型及Keggin阴离子的影响,分析了PEO-(NH₄)₃PMo12O₄₀及PEO-H₃PMo12O₄₀复合膜质子电导提高的原因.其中PEO-(NH₄)₃PMo12O₄₀质子导电聚合物电解质复合膜的室温电导率最高可达1.4×10_-3S/cm.     

双帽Keggin型杂多阴离子[PM12O40(VO)2]n-(M=Mo,n=5; M=V,n=9)的离散变分方法研究

使用密度泛函理论的离散变分方法(DFT-DVM)研究了双帽Keggin型杂多阴离子[PM₁₂O₄₀(VO)₂]^n--(M=Mo,n=5; M=V,n=9),即[PMo₁₂O₄₀(VO)₂]^5- (a)和[PV₁₂O₄₀(VO)₂]^9- (b)的电子结构,讨论了双帽的形成对Keggin型杂多阴离子的电子结构和催化性质的影响,并与其Keggin型杂多阴离子(PM₁₂O₄₀)_n-(M=Mo,n=3; M=V,n=15)的计算结果进行了对比分析,计算结果表明,双帽的形成对Keggin型杂多阴离子的电子结构产生了很大的影响,因而它们在催化活性上可能会表现出较大的差异.     

微波液相法一步合成H3PW12O40/Bi2WO6光催化剂及其脱氮性能

采用微波液相法一步合成了固载型H₃PW₁₂O₄₀/Bi₂WO₆光催化剂. 通过紫外-可见漫反射光谱(UV-Vis)、 场发射扫描电子显微镜(SEM)、 表面积及孔隙度(BET)测定、 氨气程序升温脱附(NH₃-TPD)、 吡啶吸附红外光谱(Py-FTIR)和X射线衍射(XRD)对所合成催化剂的结构和性质进行了考察, 并以吡啶浓度为15 mg/g的模拟油对光催化剂的脱氮效果进行评价. 结果表明, 与传统浸渍固载法相比, 微波液相一步法不仅能高效合成H₃PW₁₂O₄₀/Bi₂WO₆光催化剂, 且所合成的催化剂能被低能量的光激发. 固载H₃PW₁₂O₄₀不但能提高Bi₂WO₆纳米颗粒的表面酸量, 还能通过改变Bi₂WO₆前驱液的酸强度来调控催化剂形貌. 在H₃PW₁₂O₄₀固载量为15%(质量分数), 微波功率为800 W, 反应时间为90 min条件下得到的H₃PW₁₂O₄₀/Bi₂WO₆的光催化脱氮活性最高, 在催化剂与模拟油质量比为1/300, 500 W氙灯光照60 min的最佳光催化反应条件下, 模拟油脱氮率达到92.63%.     

PEO-12-钨磷酸掺杂的质子导电聚合物电解质膜

以聚氧乙烯(PEO)为基质,在其中掺杂适量的钨磷酸,制备PEO-H3PW12O40质子导电聚合物电解质膜.XRD及IR测试表明体系中Keggin阴离子与PEO链相互作用形成新的化合物;Keggin阴离子的存在有利于水合质子的形成.PEO-H3PW12O40复合膜的电导率室温最高可达4.0×10-3S·cm-1.     

PW/SBA-15负载型催化剂的性能研究

合成、表征了一系列SBA-15负载H₃PW₁₂O₄₀(PW)催化剂.负载量高达60%以上时,XRD仍未检测到催化剂上有PW晶相峰.负载后PW保持其Keggin结构,但与载体之间存在较强的相互作用.通过改变PW负载量可调变催化剂的酸性,制得适用于中强酸和弱酸性催化反应的介孔固体酸催化剂.     

An efficient and mild carboxylation of multiwall carbon nanotubes using H2O2 in the presence of heteropolyacid

A clean,fast,and facile oxidation of multiwalled carbon nanotubes（MWCNTs） by H₂O₂/heteropolyacid(H₃PW₁₂O₄₀) gave highly carboxylated MWCNTs under mild conditions,at a conveniently accessible temperature.After an easy workup,the product was characterized by SEM,XRD,and FT-IR.     

PEO-12-钨磷酸质子导电聚合物电解质膜

以聚氧乙烯(PEO)为基质, 在其中掺杂适量的钨磷酸, 制备PEO-H₃PW₁₂O₄₀质子导电聚合物电解质膜. XRD及IR测试表明体系中Keggin阴离子与PEO链相互作用形成新的化合物; Keggin阴离子的存在有利于水合质子的形成. PEO-H₃PW₁₂O₄₀复合膜的电导率室温最高可达4.0×10^－3 S•cm^－1.     

trz-Cl-Cu-PMo12的合成、 表征及催化氧化碘离子性能

以H₃PMo₁₂O₄₀为前驱体, 采用水热法使1,2,4-三氮唑-3-甲酸进行原位脱羧后, 合成了1,2,4-三氮唑修饰的Keggin型多金属氧酸盐基金属-有机框架化合物(trz-Cl-Cu-PMo₁₂), 并通过X射线单晶衍射、 红外光谱(IR)、 热重分析(TG)、 X射线衍射(XRD)、 扫描电子显微镜(SEM)及元素分析等手段对其进行了表征. X射线单晶衍射及元素分析表明, 该晶体化合物的结构式为[Cu₆Cl_0.5(C₂H₂N₃)₄][PMo₁₂O₄₀][Cu₆Cl_0.5(C₂H₂N₃)₄], 且由1个经典的 Keggin 型[PMo₁₂O₄₀]^3-和2个[Cu₆Cl_0.5(C₂H₂N₃)₄]^1.5+以近似中心对称的方式构成, 各组分之间通过超分子作用形成一维(1D)~三维(3D)结构. 催化性能研究结果表明, 该非均相催化剂在催化过氧化氢氧化碘离子为碘单质的反应中, 经4 min 35 s到达终点时, 反应速率高达1.42×10^-5 mol·L^-1· s^-1, 碘单质生成速率提高了约551倍. 催化剂重复使用8次, 转化率仍然高达99.6%, 表现出优异的催化活性, 且具有良好的可重复性.     

氨基醇杂多酸类离子液体催化环酮的Baeyer-Villiger氧化反应

合成了一系列氨基醇杂多酸类离子液体, 并将其用于催化环酮的Baeyer-Villiger氧化反应. 以2-庚基环戊酮为模板底物, H₂O₂为氧化剂, 探究了此类氨基醇杂多酸类离子液体的催化活性, 筛选出催化活性最高的催化剂为[Pro-ps]H₂PW₁₂O₄₀, 最佳反应条件: n(2-庚基环戊酮)∶n(催化剂)∶n(H₂O₂)=1∶0.03∶4, 反应温度40 ℃, 反应时间8 h, 无溶剂. 在最佳条件下, 2-庚基环戊酮的转化率为98.19%, 产物δ-十二内酯的选择性可达82.84%. 水相中的离子液体[Pro-ps]H₂PW₁₂O₄₀经干燥后可以重复使用. 经过5次循环使用后催化活性未见明显下降. [Pro-ps]H₂PW₁₂O₄₀还可用于催化其它多种环酮的Baeyer-Villiger氧化反应, 结果表明, 该催化剂具有良好的重复使用性和底物普适性.     

一种基于2,6-双(1,2,4-三唑-1-基)吡啶的新型多酸基无机-有机杂化材料的合成、结构与质子导电性能研究

采用水热法合成了一种新型多酸基无机-有机杂化材料{[Co(btp)(Hbtp)(H₂O)₃](PW₁₂O₄₀)·3H₂O}_n(1),并对化合物1进行了结构测定。X射线单晶衍射结果显示，Co(Ⅱ)离子通过btp配体连接形成一维链，[PW₁₂O₄₀]^3-游离于相邻一维链相互交叉形成的孔隙中，从而扩展成三维结构。热重分析表明化合物1具有良好的热稳定性。此外，还对化合物1的质子导电性能进行了研究。结果表明，化合物1在358 K和98%RH条件下的质子电导率为6×10^-5 S·cm^-1。     

以PEO为基质的离子及质子导电聚合物电解质

本文以PEO-LiClO₄为基质,在其中加入适量的纳米氧化锌及氧化锡,制备PEO-LiClO₄-ZnO及PEO-LiClO₄-SnO₂离子导电聚合物电解质膜,测定了复合电解质膜的电导率,并探讨了纳米粒子与PEO链的相互作用,提出复合电解质膜的电导率提高的主要影响因素。本文还合成以PEO为基质的PEO-12-钨硅酸质子导电聚合物电解质膜,讨论12-钨硅酸的加入对PEO的构型及Keggin离子的影响并分析PEO-12-钨硅     

缩氨基硫脲衍生物受体的合成及阴离子识别研究

利用简便的方法设计合成了三种缩氨基硫脲衍生物受体分子. 利用紫外-可见吸收光谱及¹H NMR考察了其与 F^－, Cl^－, Br^－, I^－, CH₃COO^－, C₃H₇COO^－, ClO₄^－, NO₃^－等阴离子的作用. 结果表明, 该类受体分子与阴离子形成氢键配合物, 加入F^－, CH₃COO^－, C₃H₇COO^－时, 溶液颜色由无色转变为黄色, 而加入其它阴离子则无变化, 从而实现对这三种阴离子的裸眼检测. 通过计算可知, 同种受体分子对此三种阴离子的作用为F^－＞C₃H₇COO^－＞CH₃COO^－. 随着苯环上取代基的变化, 此三种受体分子对三种阴离子的作用呈现出有规律的变化, 即o-F取代的受体分子对阴离子的识别作用大于其它两种受体分子, 且主客体间形成1∶1的配合物. ¹H NMR滴定及质子溶剂效应为受体分子与阴离子间的氢键作用本质提供了直接依据.     

H2 Formation on Cosmic Grain Siliceous Surfaces Grafted with Fe+: A Silsesquioxanes‐Based Computational Model

Cosmic siliceous dust grains are involved in the synthesis of H₂ in the inter‐stellar medium. In this work, the dust grain siliceous surface is represented by a hydrogen Fe‐metalla‐silsesquioxane model of general formula: [Fe(H₇Si₇O_12?n)(OH)_n]⁺ (n=0,1,2) where Fe⁺ behaves like a single‐site heterogeneous catalyst grafted on a siliceous surface synthesizing H₂ from H. A computational analysis is performed using two levels of theory (B3LYP‐D3BJ and MP2‐F12) to quantify the thermodynamic driving force of the reaction: [Fe‐T7H₇]⁺+4H→[Fe‐T7H₇(OH)₂]⁺+H₂. The general outcomes are: 1) H₂ synthesis is thermodynamically strongly favored; 2) Fe‐H / Fe‐H₂ barrier‐less formation potential; 3) chemisorbed H‐Fe leads to facile H₂ synthesis at 20≤T≤100 K; 4) relative spin energetics and thermodynamic quantities between the B3LYP‐D3BJ and MP2‐F12 levels of theory are in qualitative agreement. The metalla‐silsesquioxane model shows how Fe⁺ fixed on a siliceous surface can potentially catalyze H₂ formation in space.     

基于去保护机理的新型H2O2荧光探针的制备及应用

合成的3',6'-对戊酰硼荧光素是一种基于去保护机理的高灵敏H₂O₂荧光增强化合物, 能灵敏地检测出样品中H₂O₂的含量. 用IR, ¹H NMR 对该探针的结构进行了表征, 并且讨论了反应时间、溶剂、碱对探针合成的影响. 研究了探针的最佳响应时间, 结果表明检测过程中反应的最佳时间为3 min. 该探针在2.3×10^－12～2.0×10^－8 mol/L H₂O₂溶液范围内呈荧光增强趋势, 检测下限为2.3×10^－12 mol/L. 此探针重现性良好, 在血清中检测H₂O₂的回收率在93.9%～102.2%之间, 结果令人满意, 具有一定的实用价值.     

Vibrational-state-selected ion—molecule reaction cross sections at thermal energies

A method designed to measure relative ion—molecule reaction rates at thermal collision energies for selected reactant ion vibrational states is described. Relative reaction rates are determined for the three endothermic reactions: H₂⁺ (υ)(He,H)HeH⁺, H₂⁺ (υ)(Ne,H)NeH⁺, D₂⁺(υ)(Ne, D)NeD⁺, and for the two exothermic reactions H₂⁺ (υ)(H₂, H)H₃⁺, D₂⁺(υ)(D₂, D)D₃⁺, whereby data are evaluated for υ = 0–8 for H₂⁺ and for υ = 0–12 in the case of D₂⁺. The results are analyzed in terms of a modified statistical model designed for reactions that go through a collision complex. It is found that all data can be satisfactorily described within this model.     

Conformational Transformations of (C12H25NH3+)(Pyridinesulfonate) in the Solid State

The phase‐transition behaviors, crystal structures, and dielectric properties of four kinds of simple 1:1 organic salts of (C₁₂H₂₅NH₃⁺)(benzenesulfonate) and (C₁₂H₂₅NH₃⁺)(pyridine sulfonates) were examined from the viewpoint of intermolecular hydrogen‐bonding interactions and dynamic conformational transformation in molecular assemblies. Crystals of (C₁₂H₂₅NH₃⁺)(benzenesulfonate) and (C₁₂H₂₅NH₃⁺)(3‐pyridinesulfonate) were isostructural and solid–solid and solid–liquid‐crystal smectic A (SmA) phase transitions were observed. These two crystals formed rodlike cation–anion assemblies. However, the two salts, (C₁₂H₂₅NH₃⁺)(2‐pyridinesulfonate) and (C₁₂H₂₅NH₃⁺)(4‐pyridinesulfonate), formed largely bent L ‐shaped cation–anion conformations. Interesting conformational transformations from rodlike to L ‐shaped assemblies were observed in (C₁₂H₂₅NH₃⁺)(2‐pyridinesulfonate) and (C₁₂H₂₅NH₃⁺)(3‐pyridinesulfonate).     

正离子Gemini表面活性剂/负离子聚电解质相互作用的研究

摘要 采用荧光探针法和电导法研究了正离子偶联表面活性剂(C₁₂H₂₅(CH₃)₂N-(CH₂)₆-N(CH₃)₂C₁₂H₂₅•2Br) (12-6-12• 2Br^－)和带相反电荷聚电解质聚丙烯酸钠(NaPA)的相互作用, 结果表明: 由于静电相互作用, 12-6-12•2Br^－和NaPA之间可以形成类胶束或复合物. 对比十二烷基三甲基溴化铵(DTMAB)与NaPA复配体系的荧光光谱, 发现偶联表面活性剂与NaPA的相互作用强于传统表面活性剂. 此外, 还研究了盐和醇对偶联表面活性剂/聚丙烯酸钠的复配体系微极性的影响, 发现盐和醇对表面活性剂在聚电解质上形成类胶束和复合物的溶解都有一定的促进作用.     

The reactions of some interstellar ions with benzene,cyclopropane and cyclohexane

The reactions of the cyclic molecules C₆H₆ (benzene), c-C₃H₆ (cyclopropane) and c-C₆H₁₂ (cyclohexane) with ArH⁺ (ArD⁺), H₃⁺, N₂H⁺, CH₅⁺, HCO⁺, OCSH⁺, C₂H₃⁺, CS₂H⁺ and H₃O⁺ have been studied at 300 K using a SIFT apparatus. All the reactions except those of C₂H₃⁺ proceed via proton transfer and all are fast except the H₃O⁺ and CS₂H⁺ reactions with c-C₆H₁₂ which are endothermic and which establish that the proton affinity of c-C₆H₁₂ is 160 ± 1 kcal mol⁻¹, which is considerably lower than the published value. In the c-C₃H₆ and the c-C₆H₁₂ reactions multiple products are observed and hence “breakdown curves” for the protonated molecules are constructed and the appearance energies of the various ion products are consistent with available thermochemical data. The reactions of C₂H₃⁺ with these cyclic molecules are atypical within this series of reactions in that they appear to proceed largely via hydride ion transfer. The implications of the results of this study to interstellar chemistry are alluded to.     

新型四酰胺杯[4]氮杂冠醚的合成及对阴离子的光化学传感性质研究

合成了一类新型四酰胺杯[4]氮杂冠醚(5a, 5b), 用紫外和荧光光谱研究了主体与阴离子客体之间的识别性能. 主体分子5a或5b加入到对硝基酚氧阴离子的CHCl₃溶液中, 主客体间形成超分子复合物使得客体阴离子423 nm处吸光度降低且溶液从黄色变为无色. 受体5a, 5b与p-NO₂C₆H₄O^－, F^－, 相互作用, 荧光光谱发生变化, 并且对于p-NO₂C₆H₄O^－具有较好的选择性识别能力, 其荧光光谱强度改变强弱的顺序为p-NO₂C₆H₄O^－＞F^－＞H₂PO₄^－>>Cl^－, Br^－, I^－. 荧光光谱滴定的结果经非线性拟合, 结果表明主客体间形成1∶1络合物.     

Ab initio study of the formation of C3H3+ from the reaction of CH3+ with acetylene

Ab initio molecular orbital theory has been used to study the mechanism of the formation of C₃H₃⁺ from the reaction of CH₃⁺ with acetylene. The highest level geometry optimizations and frequencies were computed at MP2-FC/6-31G**; single point energies of all the critical structures were computed to the MP4-FC/6-31G**//MP2-FC/6-31G** theory level. One of the three alternative transition structures leading to the formation of C₃H₃⁺ gives the cyclopropenyl cation and the other two the propargyl cation. The proportions of C₃H₂D⁺ and C₃HD₂⁺ obtained when CD₃⁺ reacts with acetylene, and the composite nature of the metastable peak observed for the [C₃H₅]⁺→[C₃H₃]⁺ + H₂ fragmentation are explained by assuming a different degree of deuterium scrambling depending on the energy of the system. © 1996 by John Wiley & Sons, Inc.