New cyano-substituted copolymers containing biphenylenevinylene and bithienylenevinylene units: synthesis,optical, and electrochemical properties

Two new cyano-substituted copolymers containing biphenylenevinylene and bithienylenevinylene moieties (DCN-PPV and DCN-PTV) were synthesized by a stille condensation reaction with Pd(PPh₃)₄ as catalyst. Their structures were confirmed by ¹H NMR, IR spectroscopy, and elemental analysis. The thermal, optical, and electrochemical properties of the polymers were investigated. The results show that the polymers possess high thermal decomposition temperature and reversible n-doping/dedoping processes. In addition, DCN-PTV has higher electron affinity with a low LUMO energy level of −3.84 eV and a relatively broader absorption band covering 300–780 nm, indicating that DCN-PTV could be a potential n-type conjugated polymer in optoelectronic devices.     

一种新型含卟啉的环金属化有机配体的设计、合成与性质

采用Aldol、Adler缩合、Michael加成、Vils-meier和Knoevenagel等反应合成一种新型的D-π-A型的含C∧N∧N结构的环金属化有机配体：反式-4-[2-（5,10,15,20-四苯基卟啉基）乙烯基]-N-{4-[（2-苯基-6-吡啶基）吡啶]苯甲基}吡啶溴盐（简写为TPPB）。用核磁共振氢谱、碳谱和电喷雾质谱等手段对其结构进行了表征,初步研究了该化合物的紫外-可见光谱、荧光光谱、电化学和热稳定性。结果表明目标化合物有较好的溶解性和荧光性质,为寻找新的发光材料进行了有益的探索。     

Castor oil-based polyurethane coatings containing benzyl triethanol ammonium chloride: synthesis,characterization, and biological properties

In the present work, benzyl triethanol ammonium chloride (BTEAC) was employed as a reactive bactericidal additive for preparing of polyurethane coatings. In this regard, castor oil as a renewable resource-based polyol, polyethylene glycol (PEG1000), and BTEAC were reacted with toluene diisocyanate. Physical, mechanical, and thermal characteristics as well as biocompatibility and antibacterial properties of polyurethanes were evaluated. The prepared polyurethanes showed two-phase structure with soft and hard segments glass transition temperature transitions in the range of 18–70 and 85–153 °C, respectively. Initial modulus and tensile strength were improved for coatings with higher BTEAC content, while elongation at break and thermal stability were decreased. Hydrophilicity of coatings was increased for polyurethanes based on higher content of BTEAC and PEG1000. Polyurethanes with higher BTEAC content showed better cytocompatibility for mouse L929 fibroblast cells. Moreover, coatings with higher hydrophilicity and BTEAC content displayed superior antibacterial activity against both Escherichia coli and Staphylococcus aureus bacteria.     

Fabrication and characterization of poly(ferric chloride)-polyamine flocculant and its application to the decolorization of reactive dyes

By combining polyferric chloride (PFC) and poly(epichlorohydrin-dimethylamine) [P(ECH-DAM)], the development, characterization, and application of PFC-P(ECH-DAM) was conducted in this paper. The novel reagents were characterized by means of several typical properties and morphological analysis. The flocculation performance and subsequent mechanism were also examined for the coagulation treatment of reactive dye suspensions. Experimental results showed that the composite PFC-P(ECH-DAM) exhibited promoted characteristics, such as increased efficient polymeric speciation concentration, improved zeta potential, and enhanced flocculation performance. The morphological analysis verified the amorphous molecular structure of PFC-P(ECH-DAM) with a relatively dense branch network and sheet-like structure adhesion to each other. Increase of cationic P(ECH-DAM) proportion resulted in gradual reduction of Fe_a/Fe_b content, increase of Fe_c concentration, and improvement of zeta potential in PFC-P(ECH-DAM). The positive charge in P(ECH-DAM) and PFC-P(ECH-DAM) exhibited a decreasing tendency with increase of amine group content in cross-linker molecule. The increase of P(ECH-DAM)/Fe mass ratio and amine group of cross-linker in PFC-P(ECH-DAM) favored the destabilization of dye molecules due to their disturbance on zeta potential, Fe polymerization degree, molecular weight, and flocculation mechanism of the composite reagent.     

Highly fluorescent dendrimers containing stilbene, and 4-styrylstilbene with resorcinarene cores: synthesis and optical properties

Dendron conjugated branches of stilbene and 4-styrylstilbene groups have been attached to resor-cinarene cores. A noticeable effect in solution for all dendrimers was observed in the fluorescence quantum yield. The optical properties do not change with concentration in solution. The optical properties of thin films are identical to those of the solutions indicating the absence of intermolecular interactions. The dendrimers were characterized by 1H, 13C NMR, FTIR, UV-Vis, fluorescence spectroscopy, MALDI-TOF or FAB+ mass spectrometry, and elemental analysis.     

Study on synthesis and properties of hydroxyapatite nanorods and its complex containing biopolymer

Regular hydroxyapatite nanorods were synthesized using polyethylene glycol as chemical additive and determined by Fourier transform infrared spectrometer, X-ray diffraction and transmission electron microscope. The results showed that irregular quadrate polyethylene glycol/hydroxyapatite complex had formed in the aqueous solution, then hydroxyapatite nanorods with the diameter of about 10–15 nm and the length of 30–50 nm were obtained after calcining. The optimum calcining temperature was 500 °C. Nucleation and growth mechanism of the hydroxyapatite nanorods was illustrated. In addition, the stability of the HAP nanorod in the aqueous suspended solution was also considered. The addition of dispersant such as sodium chloride, kalium chloride and sodium dodecyl sulfonate was helpful for the stability of suspended hydroxyapatite nanorod and the mechanism was discussed. Dextran/hydroxyapatite complex with homogeneous size distribution was synthesized, and significant improvements in the mechanical properties were obtained for sintered specimens of the dextran/hydroxyapatite complex in comparison to pure HAP.     

The synthesis and optical properties of fluorescent quinoxalines and of electrospun fibers containing fluorescent quinoxaline

Heterocyclic fluorophores are useful materials in the search for new biologically active compounds and diagnostic methods. We have been interested in the chemistry of nitrogen-containing heterocyclic molecules for many years. Quinoxaline is a representative fluorophore. We have reported on several quinoxalines in recent years. Quinoxaline can easily change its absorption and emission wavelength by oxidation with the proton base in the nitrogen of the quinoxaline ring. In this study, we designed and synthesized several 2,3-distyrylquinoxaline and thieno[3,4-b]quinoxaline derivatives, Each with different electron-donating capabilities. The designed quinoxalines were substituted for the dodecyloxy groups on the benzene ring and stillbene groups were attached by knoevenagel reaction or Hornor-Wadsworth-Emmons (HWE) reaction on the 2,3-positions of the pyrazine ring. They amplified the electron donating capability of the quinoxaline structure. Thus, the weak base property of nitrogen in the heterocyclic ring was increased, especially in a protonic condition. The property in an acidic condition was revealed by fluorescence quenching. However, fluorescent spectral change was observed, especially when the N,N-dimethylamino group was attached to the stillbene group. These properties were also observed in electrospun fibers containing those synthesized compounds. Electrospun fibers contained quinoxaline colorants are expected to have various applications in chemosensors.     

New blue phosphorescent iridium complexes containing phenylpyridine and triazole ligands: synthesis and luminescence studies

The synthesis and luminescence of iridium(III) complexes containing new phenylpyridine (C(see test for symbol)N) ligands, 4-Me-4'-F-ppy, 4-Me-4'-CF3-ppy and 4-OMe-4'-CF3-ppy, were studied. These ligands were designed for development of the blue light-emitting iridium complexes by introducing the electron-withdrawing group (F, CF3) and the electron-donating group (Me, OMe) at the para positions of the phenyl and pyridine ligand rings, respectively. As an ancillary ligand, trzl-CMe3 was employed where trzl-CMe3 represents 2-(5-tert-butyl-2H-1,2,4-triazol-3-yl)pyridine. The resulting iridium complexes, Ir(4-Me-4'-F-ppy)2(trzl-CMe3), Ir(4-OMe-4'-CF3-ppy)2 (trzl-CMe3) and Ir(4-Me-4'-CF3-ppy)2(trzl-CMe3) exhibited the blue emission at 472, 484 and 494 nm in CH2Cl2 solution, respectively. Ir(4-Me-4'-F-ppy)2(trzl-CMe3) showed the most hypsochromic shift in photoluminescence (PL) among the complexes prepared herein. In the electroluminescence (EL) spectra, Ir(4-Me-4'-F-ppy)2(trzl-CMe3) and Ir(4-Me-4'-CF3-ppy)2(trzI-CMe3) exhibited the luminescence peak at 437 nm and 496 nm, respectively. In the aspect of blue emission color purity, Ir(4-Me-4'-F-ppy)2(trzl-CMe3) had the CIE coordinates of (0.176, 0.143), very close to the saturated standard blue emission.     

含咔唑PPV类超支化聚合物的合成及性能

以CpCo（CO）2为催化剂在紫外光照射的条件下，以3，6-二[（4-乙炔基）苯乙烯基]-N-辛基-咔唑双炔和1-辛炔作为单体，通过[2＋2＋2]环三聚反应合成了含咔唑PPV类超支化聚合物。采用红外光谱、核磁共振谱、热失重分析、紫外吸收光谱、荧光光谱、循环伏安法等方法对聚合物进行结构表征与性能测试，所得到的聚合物都溶于普通的有机溶剂（比如四氢呋喃、二氯甲烷、氯仿、甲苯等）。这类聚合物都表现出优异的热稳定性，它们的起始分解温度在378℃以上，在800℃时，聚合物的残余碳化率高达63％；荧光光谱显示，在光激发的条件下，聚合物在二氯甲烷溶液中发射蓝光，其荧光量子效率高达80％，电化学分析表明聚合物具有较好的空穴传输能力。     

Optical properties of aluminophosphate glasses containing silver, tin, and dysprosium

The spectroscopic properties of a Dy³⁺-doped aluminophosphate glass containing silver and tin were reported. Different oxidation and aggregation states of silver were obtained by varying silver concentration and glass thermal history. The addition of silver and tin at the lowest concentration studied results in Dy³⁺ ions emission under nonresonant UV excitation in connection with the appearance of an excitation band around 270 nm, which is associated to isolated Ag⁺ ions and twofold-coordinated Sn centers. The increase in silver and tin concentration leads to a broadening of aforementioned band and to the presence of charged silver dimers as evidenced by the appearance of an excitation band around 330 nm. The data indicated that light absorption might take place at ionic silver species and twofold-coordinated Sn centers, followed by energy transfer to Dy³⁺ ions. After heat treatment, ionic silver species were reduced to atomic Ag by tin with the subsequent formation of Ag nanoparticles (NPs) inside the dielectric host. A quenching effect in Dy³⁺ ions luminescence was shown with the presence of the Ag NPs, most notably for excitation of ⁶H_15/2 → ⁴F_9/2, ⁴I_15/2, ⁴G_11/2 transitions, which were in resonance with the dipole absorption mode of the particles. The silver NPs were believed to provide radiationless pathways for excitation energy loss in Dy³⁺ ions.     

Graphene-based materials: synthesis, characterization, properties, and applications

Graphene, a two-dimensional, single-layer sheet of sp(2) hybridized carbon atoms, has attracted tremendous attention and research interest, owing to its exceptional physical properties, such as high electronic conductivity, good thermal stability, and excellent mechanical strength. Other forms of graphene-related materials, including graphene oxide, reduced graphene oxide, and exfoliated graphite, have been reliably produced in large scale. The promising properties together with the ease of processibility and functionalization make graphene-based materials ideal candidates for incorporation into a variety of functional materials. Importantly, graphene and its derivatives have been explored in a wide range of applications, such as electronic and photonic devices, clean energy, and sensors. In this review, after a general introduction to graphene and its derivatives, the synthesis, characterization, properties, and applications of graphene-based materials are discussed.     

New polymer mortars containing polymeric wastes. Part 1. Microstructure and mechanical properties

Recycling industrial wastes as filler components and/or aggregates in polymer mortars makes these materials very interesting from an ecological and safety point of view. In addition, the resulting materials have useful physical and mechanical properties. Four recycled fillers (powdered rubbers, tyre rubbers, micronized tyre fibers and milled electrical cable wastes) have been used to formulate new polymer mortars. The comparison of their mechanical properties and microstructures with those of a plain polymer mortar indicates that the presence of recycled waste affects the physical–mechanical behavior (compressive and flexural strengths, microstructure). The use of silane coupling agents has been also considered and its effect in leading to more compact materials is reported and discussed.     

Rapid and eco-friendly synthesis of NiO/ZnO nanocomposite and its application in decolorization of dye

In this work NiO/ZnO nanocomposite was synthesized via simple, rapid and eco-friendly microwave-assisted method. Prepared NiO/ZnO nanocomposite was characterized by X-ray diffraction pattern, scanning electron microscopy, transmission electron microscopy, UV–Visible absorption spectroscopy and Fourier transform infrared spectroscopy. Vibrating sample magnetometer analysis showed the ferromagnetic behavior of nanocomposite. In the following, prepared nanocomposite was used for photodegradation of methylene blue and rhodamin B under ultraviolet light irradiation. The results showed that nanocomposite has excellent photocatalyst performance.     

新型噁二唑电子传输材料的分子设计合成、结构与性能关系研究

随着有机电致发光器件(OELD)的发展,有机电子传输材料研究逐渐引起人们广泛兴趣.制备了3种不同长共轭结构的新型2,5-二芳基-1,3,4-噁二唑类衍生物(4a～4c),以FTIR、1HNMR、TGA、C-V、UV-vis、FL对化合物的结构与性能进行了表征和研究.结果显示,噁二唑类衍生物分子结构对其热稳定性和分子的能级结构明显产生影响,分子中π电子共轭程度提高可有效地提高电子亲和势,分子极性和分子共轭度提高均有利于提高噁二唑衍生物(4c)的热稳定性.     

Hydrothermal synthesis,characterization and properties of SnS nanoflowers

Novel tin (II) sulfide (SnS) nanoflowers were successfully synthesized via a simple thioglycollic acid (TGA)-assisted hydrothermal process at 250 °C. X-ray diffraction, scanning electron microscopy and energy-dispersive spectrometry were employed to characterize the structure, morphology and chemical composition of the product, the results of which reveal that the product is composed of well crystallized orthorhombic SnS nanoflowers. The band gaps were obtained by analyzing UV-vis absorption spectrum; herein, the direct and indirect optical band gaps are 1.53 and 1.43 eV, respectively. Furthermore, we discussed critical factors (e.g., TGA, SnCl₂/Na₂S mol ratio of the reactants, hydrothermal temperature, and sulfur source) for hydrothermal formation of the SnS nanoflowers.     

碳量子点的合成、性质及其应用

碳量子点(CQDs,C-dots or CDs)是一种新型的碳纳米材料,尺寸在10nm以下,具有良好的水溶性、化学惰性、低毒性、易于功能化和抗光漂白性、光稳定性等优异性能,是碳纳米家族中的一颗闪亮的明星。自从2006年[1]报道了碳量子点(CQDs)明亮多彩的发光现象后,世界各地的研究小组开始对CQDs进行了深入的研究。最近几年的研究报道了各种方法制备的CQDs在生物医学、光催化、光电子、传感等领域中都有重要的应用价值。这篇综述主要总结了关于CQDs的最近的发展,介绍了CQDs的合成方法、表面修饰、掺杂、发光机理、光电性质以及在生物医学、光催化、光电子、传感等领域的应用。     

Thermodynamic properties of antiferromagnetic superconductors containing nonmagnetic,magnetic, and spin-orbit impurities

Effects of all types of impurities (nonmagnetic, magnetic, and spin-orbit) on an antiferromagnetic superconductor (AFSC) have been investigated by studying the transition temperatureT _c and the specific heat jump. We have assumed a one-dimensional electron band. The impurity scattering is treated within the self-consistent Born approximation. We find that: (a) the molecular fieldH _Q and the magnetic impurities depress superconductivity of AFSC and their pair-breaking effect is additive; (b) the effect of spin-orbit impurities is the same as that of nonmagnetic impurities—these enhance superconductivity by screening the molecular field; and (c) in the extreme dirty limit, the AFSC is described in terms of an effective pair-breaking parameter given by 1/_eff=1/₂+H _Q ² where 1/=1/₁+2/3_so(1/₁, 1/₂, and 1/_so, respectively, are the scattering rates from nonmagnetic, magnetic and spin-orbit impurities).