一种杂环磺化聚芳醚腈酮质子交换膜材料的合成及表征

用含二氮杂萘酮结构类双酚DHPZ,3,3′-二磺酸钠基-4,4′-二氟二苯酮,2,6-二氯苯腈以及4,4′-二氟二苯酮,通过缩合共聚合反应合成了一系列不同磺化度、高分子量的磺化聚芳醚腈酮.聚合物特性粘数为0·58~2·0dL/g.用红外光谱(FT-IR),核磁共振谱(1H-NMR)表征了聚合物结构.用差示扫描量热仪(DSC)和热重分析仪(TGA)研究了聚合物的耐热性能,研究表明其玻璃化温度(Tg)可达352℃,5%热失重温度大于500℃.以N-甲基吡咯烷酮为溶剂,溶液浇铸法制备了聚合物膜,并测定了膜的溶胀率以及质子交换能力.结果表明,与Nafion膜相比,磺化聚芳醚腈酮膜在相同的质子交换能力条件下,溶胀率显著降低.     

The elements of Flatland: Hartree-Fock atomic ground states in two dimensions for Z = 1–24

The Hartree–Fock problem in two dimensions (2D) has been solved for 1 ≤ Z ≤ 24 using a Gaussian basis and assuming r^?1 Coulomb interactions. The order of occupation of the one-electron states is like in the 3D case. The 1s shell is found to be particularly small and strongly bound, making the 2D hydrogen a “superhalogen” and the 2D He a “superinert gas.” In contrast to 3D, 4s¹3d² and 4s²3d³ configurations are preferred for the 2D “Sc” and “Cu,” respectively. The six first 2D atoms have stronger and the later ones weaker valence-bonding energies than do their 3D analogs. It is noted that the 2D Dirac energy expression for a hydrogenlike atom for m_j = l + 1/2 agrees with the 3D Klein–Gordon one.     

大孔树脂吸附和分离密蒙花黄色素

本文研究了用大孔树脂吸附和分离密蒙花黄色素，比较了四种树脂对密蒙花黄色素的吸附。选用经x—5作吸附剂，洗脱剂用60％乙醇，产品质量较传统法好，提取率达8％，x－5树脂非常稳定，使用15次后其吸附率仅降低4．95％。     

Synthesis and electronic energy‐level regulation of imide‐fused poly(thienylene vinylene) derivatives

A series of novel poly(thienylene vinylene) derivatives (PTVs), P20‐P24 , with imide substituents were designed and synthesized by palladium‐catalyzed Stille coupling polymerization, wherein the imide substituent density was decreased gradually, which allowed us to explicitly study the effect of electron‐deficient substituent on the optical, electrochemical, and photovoltaic properties of the PTVs. All of the four polymers showed broad absorption bands with optical bandgaps between1.66 and 1.78 eV. By reducing density of electron‐deficient imide group, the LUMO energy levels of the polymers could be tuned gradually from ?3.75 to ?3.43 eV, with HOMO levels upshifted from ?5.64 to ?5.16 eV. Bulk heterojunction solar cells with the polymers as donor and PC₇₁BM as acceptor demonstrated very different excitons dissociation behavior. With decreasing the imide‐fused unit density, the open‐circuit voltage (V_OC) values in the devices decreased from 0.78 to 0.62 V, whereas the short‐circuit currents (J_SC) increased from 0 to 2.26 mA cm^?2 and then decreased to 1.01 mA cm^?2. By adjusting the electron‐withdrawing imide substituent density, power conversion efficiency of the PTVs‐based solar cells can be increased to four times, reached 0.86%. To the best of our knowledge, this is the first systematic study of the relationship between molecular energy level and photovoltaic properties of PTVs. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 4975–4982     

Rapid analysis of Saposhnikovia divaricate decoction metabolism in rats by UHPLC–Q-TOFMS and multivariate statistical analysis

Saposhnikovia divaricata is a commonly used traditional Chinese medicine in treating various diseases such as pyrexia, rheumatism and headache. So far, there have been few reports on the metabolism of orally administered Saposhnikovia divaricate decoction (SDD), hindering further study on its bioactive components and their pharmacological characteristics. In the present study, ultra-performance liquid chromatography–quadrupole time-of-flight mass spectrometry (UHPLC–Q-TOFMS) was used coupled with principal component analysis (PCA) and partial least squared discriminant analysis (PLS-DA) to rapidly discover and identify the metabolites of SDD. According to the result of PLS-DA, a total of 139 ions of interest including 87 positive ions and 52 negative ions were extracted as SDD-related xenobiotics in urine. Finally, 12 and 65 compounds were identified as absorbed parent components and metabolites of SDD, respectively. Among them, 40 new metabolites were reported for the first time. Our results suggested that hydrolysis, hydroxylation, glucuronidation and sulfation are the major metabolic pathways of chromones, while hydroxylation, hydrogenation and sulfation are the main metabolic pathways of coumarins. This study is the first to explore the absorption and metabolism of SDD using UHPLC–Q-TOFMS, with results providing a basis for further study of its pharmacokinetics and discovery of its bioactive components.     

Structure and stability of AuXe n Z (n = 1–3, Z = −1, 0, +1) clusters

We have explored the structures and stabilities of AuXe _n ^Z (n = 1–3, Z = ?1, 0, +1) cluster series at CCSD(T) theoretical level. The electron affinities and ionization potentials are correlated to the HOMO–LUMO gaps. The role of the interaction was investigated using the natural bond orbital analysis.     

含二氮杂萘酮结构磺化聚酰亚胺共聚物的合成及其膜性能研究

将磺化二胺单体4,4′-二(4-氨基苯氧基)联苯-3,3′-二磺酸(BAPBDS),含二氮杂萘酮结构的二胺1,2-二氢-2-(4-氨基苯基)-4-[4-(4-氨基苯氧基)-苯基]-二氮杂萘-1-酮(DHPZDA)和1,4,5,8-萘四甲酸二酐(NTDA)进行缩合聚合反应,通过改变磺化二胺单体BAPBDS的含量,合成了一系列不同磺化度的聚酰亚胺(SPIs).采用FT-IR,1H-NMR表征了聚合物的结构,热重分析仪(TGA)研究了聚合物的耐热稳定性.以间甲酚为溶剂,通过溶液浇铸法成膜研究了该系列聚合物膜的性能.结果表明,与其它磺化聚酰亚胺相比,该系列磺化聚酰亚胺的溶解性以及在高温下(80℃)水解稳定性有较大提高.     

Synthesis,characterization, and antibacterial activities of some rare Earth metal complexes of pipemidic acid

Eight new solid complexes of pipemidic acid (PPA) with trichlorizated rare earth metals LaCl(3), CeCl(3), PrCl(3), NdCl(3), SmCl(3), TbCl(3), DyCl(3), and YCl(3) have been synthesized. The complexes were characterized by elemental analyses, IR, NMR, and molar conductance measurements. The general formulas of the complexes are [M(PPA)(4)]Cl(3) (M=Ce(III), Pr(III), Nd(III), Sm(III), Tb(III), Dy(III), Y(III)), and [La(PPA)(4)Cl]Cl(2). At the same time, the antibacterial activities of PPA and four of its complexes were tested. The results show that PPA and its complexes all have inhibitory action against bacteria of Escherichia coli, Bacillus subtilis, Streptococcus pneumoniae, and Pseudomonas aeruginosa but not Staphylococcus aureus. We compared their antibacterial activities and found that the antibacterial activity of [La(PPA)(4)Cl]Cl(2) against S. pneumoniae is much stronger than that of PPA and the other complexes.     

Ab initio study on the reaction mechanism of ozone with bromine atom

Ab initio calculations of the potential energy surface (PES) for the Br+O₃ reaction have been performed using the MP2, CCSD(T), and QCISD(T) methods with 6‐31G(d), 6‐311G(d), and 6‐311+G(3df). The reaction begins with a transition state (TS) when the Br atom attacks a terminal oxygen of ozone, producing an intermediate, the bromine trioxide (M), which immediately dissociates to BrO+O₂. The geometry optimizations of the reactants, products, and intermediate and transition states are carried out at the MP2/6‐31G(d) level. The reaction potential barrier is 3.09 kcal/mol at the CCSD(T)/6‐311+G(3df)//MP2 level, which shows that the bromine atom trends intensively to react with the ozone. The comparison of the Br+O₃ reaction with the F+O₃ and Cl+O₃ reactions indicates that the reactions of ozone with the halogen atoms have the similar reaction mechanism. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2007     

Novel electroactive and photoactive molecular materials based on conjugated donor-acceptor structures for optoelectronic device applications

Four donor-acceptor functionalized molecular materials with symmetrical structures have been synthesized and investigated for their use in optoelectronic applications. These pi-conjugated molecules consist of one electron-donating moiety, for instance, carbazole, triphenylamine, or phenothiazine at the center, and two acceptors at each side. Introduction of different donor moieties decreases the band gaps allowing a fine-tuning of the optical and electrical properties. These materials exhibit multifunctional properties, such as a red light-emitting behavior and a large photovoltaic effect. Red organic light-emitting diodes were fabricated in a facile nondoping configuration based on these materials. Saturated red-emission is observed with a CIE of x = 0.64 and y = 0.33, and an external quantum efficiency of 0.19%. In addition, our first observation of photovoltaic response in the pi-conjugated molecule with donor-acceptor-donor structure is reported. The organic single-component photovoltaic cells were fabricated and characterized. Their open-circuit voltage and short-circuit current density are 1.1 V and 0.07 mA cm(-2), respectively. The photovoltaic effect corresponds to the absorption characteristics of the compound and depends on the nature of the electron-donating group.