荧光性多孔芳香骨架材料的简便制备 及在硝基爆炸物检测中的应用

报道了一种简便的制备高荧光性多孔有机聚合物材料的方法, 即以1,3,6,8-四溴芘(TBrPy)与硼酸类单体为构筑基元, 通过Suzuki偶联反应制备多孔芳香骨架材料LNUs. 利用傅里叶变换红外光谱、 热重分析、 氮气吸附、 固体紫外光谱和荧光光谱等分析方法对其结构与性能进行了系统表征. 分析结果表明, 该类多孔芳香骨架材料具有良好的热化学稳定性和较大的比表面积, 所得材料优异的荧光性能使其非常适合用于硝基爆炸物的选择性检测. 多孔芳香骨架材料LNUs在苯、 溴苯、 苯胺、 甲苯、 氯苯和苯酚等分子存在下, 荧光强度基本不变, 而在加入硝基苯、 对硝基苯酚和对硝基氯苯后, 荧光几乎完全猝灭, 说明该类材料对硝基苯、 对硝基苯酚和对硝基氯苯显示出专一的检测性能. 根据这一特性, 利用LNUs材料制备了一种新型便携式纸传感器, 其可以简便快速实时检测硝基爆炸物, 并在痕量检测方面展现出良好的应用前景.     

含萘基团的锆金属有机骨架材料对水中硝基芳烃爆炸物的荧光检测性能

采用分子构筑块策略设计合成了一个含萘基的直线型有机羧酸配体4,4′-(9,10-naphthalenediyl)bis-benzoic acid(H₂NDBA), 以构筑特定的骨架结构. 利用调节剂法, 通过八水合氯氧化锆与有机配体H₂NDBA的溶剂热反应, 合成了具有预期fcu拓扑结构的[Zr₆(μ₃-O)₄(μ₃-OH)₄(NDBA)₆]·7DMF·4H₂O(JLU?MOF100). 该MOF材料具有高孔隙率和良好的水稳定性. 得益于有机配体中的萘基团, JLU?MOF100具有优异的荧光性质, 基于荧光猝灭效应, 在水中对硝基芳烃爆炸物展现出良好的荧光检测性能.     

新型掺杂多孔芳香骨架材料的储氢性能模拟

基于PAF-301分子模型通过Li掺杂或B取代等模式设计了几种新型多孔芳香骨架(PAFs)材料,采用量子力学和分子力学方法对新材料的储氢性能进行研究.由量子力学计算得到了不同分子片段与H2之间的结合能,并结合DDEC方法计算了各分子片段的原子电荷分布.利用巨正则蒙特卡洛(GCMC)模拟方法计算了77和298 K下H2在不同PAFs材料中的吸附平衡性质.结果表明,H2直接与苯环的结合能较低,但掺杂Li原子能够提高H2与六元环的结合能,同时Li原子体现出较高的正电性质,B原子取代苯环中的两个C原子后,使得原有C原子电负性增强;77 K下PAF-301Li具有最高的储氢性能,而PAF-C4B2H4-Li2-Si和PAF-C4B2H4-Li2-Ge体现出较好的常温储氢性能,各种材料的常温储氢性能远低于其低温储氢性能.通过77 K下H2在PAFs材料中的等位能面分布和吸附平衡质心密度分布对H2在PAFs材料中的优先吸附位置进行分析,发现在PAF-301和PAF-301Li骨架中,由于中心能量较低的等位能区域范围较宽,H2在其中存在四个明显的吸附高密度分布区域,而其它三种PAFs晶胞中心能量较低的等位能区域范围较窄,使得H2在其中只存在两个明显的吸附高密度分布区域.     

磷酸基多孔芳香骨架材料用于提取铀离子

采用联苯为建筑基元，合成了价格低廉、操作简便、易于工业化的多孔芳香骨架材料PAF-45.通过后修饰方法，制备了带有磷酸基团的多孔芳香材料（PAF-45-PG）.通过FTIR（傅里叶变换红外光谱），TGA（热重分析），PXRD（多晶粉末X射线衍射），SEM（扫描电子显微镜），TEM（透射电子显微镜）以及N₂吸附实验，对PAF-45-PG的结构及孔道性质进行了系统的表征.由于骨架中引入了磷酸基团，PAF-45-PG具有优良的铀离子吸附性能，在pH=6的条件下可以达到100 mg·g^-1.另外，该材料成本低廉，具有可观的工业化前景，为多孔材料在能源方面的应用提供了广阔前景.     

定向合成高效捕获CO2的新型多孔芳香材料

通过简单的离子热法,以四（4-氰基联苯基）硅烷作为四面体基块,将其与无水氯化锌在充满氩气气氛的手套箱中充分研磨后密封,分别以400和550 ℃的反应温度合成了新型多孔芳香骨架材料（PAF-51）,得到PAF-51-1（400 ℃条件下）与PAF-51-2（550 ℃条件下）的比表面积分别为720和557 m²·g^-1 （BET）.与CH₄和N₂对比,该材料对CO₂具有极好的选择性吸附能力. 273 K条件下,CO₂/N₂分离指数最高可达52.2,CO₂/CH₄分离指数也达到10.3,这一性质极有可能使得PAF-51成为捕获CO₂理想材料,并对再生能源具有潜在的应用.     

嵌入配位不饱和金属位对多孔芳香骨架材料储氢性能的影响

基于密度泛函理论(DFT)和巨正则蒙特卡洛(GCMC)模拟方法,系统地研究了引入配位不饱和金属位(CUS)对PAF-30n (n = 1–4)材料储氢性能影响的规律。结果表明,77 K下PAF-302MgO₂_PBE100的最大过量质量储氢量达到7.97% (w);77 K、10 MPa下100%醇镁功能化改性PAF-302和PAF-303的绝对储氢量分别达到9.9% (w) (65.9 g∙L^-1)和15.0% (w) (50.5 g∙L^-1),分别超过美国能源部(DOE)标准80% (64.8%)和173% (26.3%),均超过在相同条件下目前储氢性能最佳的NU-1101 (9.1% (w), 46.6 g∙L^-1)。即使在243 K、10 MPa下,其绝对质量和绝对体积储氢量也能分别达到5.13% (w)和34.19 g∙L^-1,占DOE质量与体积储氢标准的93.3%和85.5%,是目前为止常温储氢性能较为均衡的多孔材料之一。结合等量吸附热(Q_st)、径向分布函数(RDF)和质心几率密度分布(MCPD)方法进一步分析,发现有机链长度增加导致孔隙率增加和体积比表面积减小,是引起多孔材料绝对质量和绝对体积储氢量此消彼长的根本原因。另外,引入CUS能提高PAFs材料对H₂分子亲和力,显著增强其体积储氢量。     

一例Eu-MOF材料的构筑及对Fe3+与硝基芳香族爆炸物的荧光检测性能

金属阳离子和硝基芳香族爆炸物的大量排放对环境和人体健康造成了严重威胁,对它们的高效检测具有重要的研究意义和挑战性,金属-有机骨架(MOFs)是一类新型的荧光传感检测材料.本文采用溶剂热法合成了一例具有fcu拓扑结构的Eu-MOF材料,[(CH₃)₂NH₂]₂[Eu₆(μ₃-OH)₈(EDDC)₆]·8DMA·3MeOH·6H₂O[JLU-MOF128,H₂EDDC=(E)-4,4′-(乙烯-1,2-取代基)二苯甲酸],并通过单晶X射线衍射、粉末X射线衍射、X射线光电子能谱、红外光谱、元素分析和热重分析对其结构及组成进行了表征.结果表明,由于荧光配体H₂EDDC的引入,JLU-MOF128表现出显著的荧光性能,在DMF溶液中对Fe³⁺、2,4,6-三硝基苯酚(TNP)和2,4-二硝基苯酚(2,4-DNP)具有较好的检测效果,K<...     

爆炸物检测用荧光聚合物材料

作为荧光传感材料,荧光聚合物不仅具有传感单元多、荧光亮度高、光稳定性好等特点,而且方便制备荧光传感薄膜,易于实现器件化,在爆炸物荧光检测中得到了广泛的研究与应用。近年来,随着荧光聚合物从传统的线型结构向支化和多孔网络结构的拓展,以及各种功能单元的引入,大量的新型荧光聚合物有效地提升了爆炸物检测的灵敏度、选择性和响应速度等性能。本综述从线型聚合物、支化聚合物、多孔聚合物三类体系出发,总结和评述了用于爆炸物荧光检测的线型共轭与非共轭聚合物、树枝状分子与超支化聚合物、无定形与结晶型多孔聚合物等典型体系的分子结构设计策略、功能特点以及传感性能,并展望了荧光聚合物未来在爆炸物检测应用中所面临的机遇和挑战。     

定向合成带电荷多孔芳香骨架材料用于碘单质的捕获和释放

采用四(4-碘苯基)硼化锂作为四面体基块, 以1,4-苯二硼酸和4,4'-联苯二硼酸作为桥联基团, 通过Suzuki偶联反应成功制备了两种带电荷多孔芳香骨架材料PAF-21和PAF-22. 实验结果证明PAFs具有优异的热稳定性和化学稳定性, 同时材料特有的带电荷芳香骨架导致它们对碘单质具有非常高的亲和力以及吸附能力. 1 g的PAF-21和PAF-22可以分别吸附大约1.52和1.96 g的碘单质. 此外, PAF-21和PAF-22在富集碘单质的过程中可以循环使用. 这类材料非常适合作为新型固体吸附剂用于捕获放射性碘单质.     

荧光传感方法检测爆炸物的研究进展

爆炸物检测是当前国际安全中迫切关注的问题之一。在过去的几十年中,大量的荧光传感材料用于荧光传感检测气态、液态和固态爆炸物见诸于报道。近年来,为了实现爆炸物的快速响应、高灵敏和高选择性的检测,研究工作者大力开发了各种新型荧光材料。这篇综述总结了近年来用于爆炸物检测的先进荧光材料,详尽、系统、重点地介绍了共轭聚合物、荧光小分子、超分子体系、具有聚集诱导发光效应的活性材料及静电纺丝纳米材料等各种荧光材料在爆炸物检测中的应用,展望了荧光传感方法在爆炸物检测领域的应用前景。     

Catalytic hydrogenation of aromatic nitro compounds by non-noble metal complexes of chitosan

Silica-supported mono-metal (such as Ni, Cu) complexes and mixed metal (such as Cu/Zn, Cu/Cr) complexes of chitosan have been prepared. It is found that these non-noble metal complexes could be used as efficient catalysts for the hydrogenation of aromatic nitro compounds. The effects of type of metal, reaction temperature and pressure, solvent, nitrogen/metal molar ratio in the complex catalysts on the yields from nitrobenzene to aniline have been examined. It was also found that catalysts are active for the catalytic hydrogenation of other aromatic nitro compounds such as 2-nitroanisole, 2-nitroaniline, 2-nitrotoluene and 1-chloro-4-nitrobenzene.     

活性炭负载氢氧化氧铋催化水合肼还原芳香族硝基化合物

采用浸渍法制备了BiO(OH)/C催化剂。催化剂的XRD谱表明,当催化剂中BiO(OH)的质量分数小于10%时,BiO(OH)在活性炭中高度分散。反应温度为75 ℃时,催化剂重复使用7次仍保持较高活性。在5 mL乙醇中以0.05 g 10%（质量分数）BiO(OH)/C,1 mmol芳香族硝基化合物和2 mmol水合肼于75 ℃反应一定的时间,所得芳胺的收率为88%～99%。     

Some peculiarities of the effect of molecular structure on the activation energy of radical gas-phase decay of aromatic nitro compounds

The relation of parameters of geometric and electronic structures to the activation energies of the radical gas-phase decomposition of nitro compounds is shown. A sufficiently simple and precise method for calculation of the activation energy is suggested.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2118–2122, December, 1994.     

The nitro aromatic compounds detection by triazole carboxylic acid and its complex with the fluorescent property

The 5-methyl-1-(4-nitrophenyl)-1H-1, 2, 3-triazole-4-carboxylic acid (1) was synthesized by an improved method. By using the compound 1 as ligand, a new complex [Cu(L)₂][Cu(L)₂(H₂O)₂] (2) was prepared firstly under hydrothermal condition. Both 1 and 2 were all used as exclusive fluorescence sensor for 2, 4, 6-trinitrophenol (TNP) for the first time. The fluorescence exploration demonstrated that they exhibit highly selective and sensitive (K_SV = 393685 M^?1 and K_SV = 213269 M^?1, respectively) sensing to TNP from other nitro aromatic compounds (NACs) with high quenching efficiency QP value of 96.76% and 93.37%, as well as low detection limit (0.68 μM and 0.37 μM, respectively). It means that complex 2 had higher selectivity due to the less interference by 4-NT and 2-NP compared with 1. Moreover, the fluorescence quenching phenomenon of sensor 1 with TNP was analyzed by density functional theory (DFT).     

Application of Cu(Hdmg)2 as a simple and cost‐effective catalyst for the convenient one‐pot reductive acetylation of aromatic nitro compounds

In this article, we have developed a novel and simple one‐pot reductive acetylation of aromatic nitro compounds with sodium borohydride (NaBH₄) in ethyl acetate (EtOAc) under reflux conditions in the presence of the bis(dimethylglyoximato)copper(II) complex [Cu(Hdmg)₂] as an efficient and cost‐effective copper‐containing catalyst. Notably, using the above‐mentioned one‐pot reaction, the corresponding acetamide derivatives were obtained in high to excellent yields.     

多孔芳香骨架吸附剂-固相萃取-高效液相色谱法同时测定辣椒粉中4种偶氮类染料

建立了固相萃取-高效液相色谱同时测定辣椒粉中对位红、酸性橙Ⅱ、苏丹红Ⅰ和苏丹红Ⅱ 4种偶氮染料的方法。以多孔芳香骨架-6（PAF-6）材料作为固相萃取吸附剂，考察并获得了影响自制固相萃取柱的萃取效率和吸附容量等主要因素。在优化条件下，4种目标分析物的检出限（LOD）为1.5~7.0 μg/L（信噪比S/N=3），定量限（LOQ）为5.0~22.1 μg/L（S/N=10），加标回收率为76.5%~89.8%，相对标准偏差（RSD）均不大于5.3%（n=6）。此外，基于量子化学计算，考察了PAF-6与目标分析物之间的相互作用机制，结果表明，目标分析物可以稳定地吸附在PAF-6分子上。该方法准确可靠，具有良好的回收率和较高的灵敏度，可用于辣椒粉中4种偶氮类染料的检测。     

interaction of nitro compounds with radicals: a quantum chemical study

Photoreduction of nitro compounds is accompanied by formation of various radical products that can react with the starting nitro compound, thus causing deviation of the decomposition kinetics from the first-order kinetics with respect to the nitro compound. The results of quantum chemical modeling of the reactions of nitro compounds with radicals and the pathways of further transformations of radical adducts formed in the reactions are presented. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 202–206, February, 2006.     

Water stability of zeolite imidazolate framework 8 and application to porous membrane-protected micro-solid-phase extraction of polycyclic aromatic hydrocarbons from environmental water samples

Zeolite imidazolate framework 8 (ZIF-8) has permanent porosity, high surface area, hydrophobic property, open metal sites and remarkable water stability. These novel properties characterize the material as being different from other moisture sensitive metal-organic frameworks and endow ZIF-8 with the potential to extract trace analytes from environmental water samples. In the present study, ZIF-8 was synthesized and used as a sorbent for micro-solid-phase extraction of 6 polycyclic aromatic hydrocarbons (PAHs) from environmental water samples for the first time. Parameters influencing the extraction efficiency such as desorption time, extraction time, desorption solvent and salt concentration were investigated. Environmental water samples collected from a local lake were processed using this novel μ-SPE procedure. ZIF-8 proved to be a very efficient extraction sorbent for the extraction of trace analytes from water samples. The limits of detection from gas chromatography-mass spectrometric analysis of PAHs were 0.002-0.012 ng/ml. The linear ranges were 0.1-50 or 0.5-50 ng/ml. The relative standard deviations for five replicates of the extractions were in the range of 2.1-8.5%.     

Polyethyleneimine‐modified porous aromatic framework and silane coupling agent grafted graphene oxide composite materials for determination of phenolic acids in Chinese Wolfberry drink by HPLC

A simple method for the determination of phenolic acids in Chinese Wolfberry drink based on polyethyleneimine modified porous aromatic framework and graphene oxide composite sorbent for pipette‐tip solid‐phase extraction was developed. Porous aromatic framework and raphene oxide composite materials were grafted by silane coupling agent (3‐Chloropropyl)‐trimethoxysilane. The modified materials were characterized by five kinds of characterization. Experimental results showed that the prepared p‐phenylenediamine, cyanuric chloride, and graphene oxide composite material had a loose structure combined with the framework which improved hydrophobicity, and polyethyleneimine to increase the selectivity with the targets. The parameters of the pipette‐tip solid‐phase extraction procedure including the amount of sorbents, volumes and types of washing solvents and elution solvents were optimized to achieve optimal extraction efficiency. Good linearity of best material was achieved in the range of 0.1–400 µg/mL with correlation coefficient of chlorogenic acid (0.9994), caffeic acid (0.9997), and ferulic acid (0.9998). Recoveries between 93.5 and 102.3% were obtained at three spiked levels with relative standard deviation ≤3.1%. The proposed method was successfully applied for the determination of phenolic acids in Chinese Wolfberry drink sample.     

New Sm (III) and Nd (III) complexes: Synthesis,structural characterization and fluorescent sensing of nitro‐aromatic compounds

In this work, four new Nd (III) and Sm (III) complexes of two pentadendate ligands (L¹ and L²) were prepared and their molecular structures were determined by single crystal X‐ray diffraction studies. X‐ray analysis showed that the Nd (III) and Sm (III) complexes of L¹ sits on a twofold crystallographic axis while the complexes of L² does not show crystallographically imposed symmetry. Absorption and photoluminescence properties of the complexes were studied both in the solid state and DMF solutions. The fluorescence sensing of nitro‐aromatic compounds [nitrobenzene (NB), 4‐nitrophenol (NP), 2,4‐dinitrophenol (DNP) and 2,4,6‐trinitrophenol (TNP)] were studied by photoluminescence spectroscopy. All four complexes showed better sensitivity towards nitrophenol (NP) with low LOD values.