Cellulose, the abundant and cost-ineffective resource, is considered to be a perfect alternative for the alleviation of energy crisis and environmental pollution. However, most processes for the treatment of cellulose are ri r currently as it is insoluble in water and conventional organic solvents due to its strong intra and inter-molecular hydrogen bonds, where the phase problem hampers its utilization widely. Here, we built a novel and efficient cooperative ionic liquid pairs system for the low temperature catalytic conversion of cellulose, which was constructed through the combination of an acidic ionic liquid catalyst and a cellulose soluble ionic liquid solvent. The catalytic decomposition behavior of microcrystal cellulose in this vi rous catalytic system was studied intensively by thermogravimetry (TG). Results show that the decomposition temperature of cellulose decreases greatly in all cooperative ionic liquid pairs, cellulose dissolved in ionic liquid solvents can be in situ catalytic decomposed by acidic ionic liquids. Furthermore, the decomposition temperature is dependent on the acidic strength of the ionic liquid catalysts, stronger acidity results in a lower decomposition temperature of the cellulose. Moreover, we found that cellulose can be decomposed at lower temperature when the ionic liquid with higher solubility of cellulose is used.

Generally speaking, the highest symmetry of a Möbius cyclacene molecule is C₂ group based on the point group theory. We here investigated two isomers of cyclacene that were composed of 18 benzene units, i.e., a hoop-like Hückel [18]-cyclacene (HC-[18]) and a Möbius strip-like Möbius[18]- cyclacene (MC-[18]). We found that in addition to being described by C₂ point group transformation, the molecular symmetry of Möbius cyclacene may also be characterized by the so-called torus screw rotation (TSR) symmetrical transformation, which is a symmetry operation of the torus group introduced here. The torus ortho nal curvilinear coordinates were also introduced to express the TSR transformation. Furthermore, both the symmetry adapted atom set and the atomic orbital set that refers to the TSR transformation are discussed. Because the TSR symmetry has cyclic group characteristics, we can establish the irreducible representations and related characteristics for this cyclic group. In addition, for these cyclacenes the irreducible representation of their molecular orbitals (MOs) may be pure while their corresponding symmetry adaptive linear combination of atomic orbital (SALC-AO) components can be numerous.

The preparation, characteristics and electrochemical performances of the sulfur-based cathode materials in lithium/sulfur batteries are reviewed in this paper. The elemental sulfur cathode material is briefly introduced. The structural designs, preparation processes, reaction mechanisms, and charge/discharge properties of organic sulfide, sulfur-porous carbon and sulfur-polymer composites as cathode materials are systematically discussed and problems associated with these materials are also analyzed. In addition, the research and application of lithium sulfides as cathode materials are also outlined. Finally, the further development of sulfur-based cathode materials and the commercialization of lithium/sulfur batteries are discussed.

We review the history, fabrication procedures, and mechanisms of TiO₂ nanotubes prepared by the anodic oxidation of titanium. The influence of various preparation factors, such as electrolytes, pH value, voltage, bath temperature, and post treatment, on the structure and morphology of the TiO₂ nanotubes are discussed. This review also summarizes the application of TiO₂ nanotubes to dye-sensitized solar cells, quantum dot solar cells, and bulk heterojunction solar cells. A perspective on the future development of TiO₂ nanotubes and their applications is tentatively discussed.

Static light scattering measurements on a microemulsion of sodium bis(2-ethylhexyl) sulfosuccinate (AOT)/water/toluene with a water to AOT molar ratio of 12 at a series of temperatures and droplet concentrations were carried out to obtain their molecular weights, aggregation number, radius, and the second Virial coefficient of the droplets at various temperatures and concentrations. The dependence of the second Virial coefficient on the temperature was used to obtain the enthalpy and entropy of the interaction between the droplets, which were -4.03×10⁴ J·mol^-1 and -139.8 J·mol^-1·K^-1, respectively. These values indicate that the energy of surfactant penetration between the droplets in the AOT/water/toluene microemulsion system is negative and the penetration is driven by enthalpy.

We studied the enthalpy relaxation dynamics of amorphous D-sorbitol by differential scanning calorimetry (DSC). A series of specific heat capacities (C_p(T)) for D-sorbitol were measured upon heating of 10 K·min^-1. The samples were subjected to thermal treatment involving isothermal annealing with different annealing time (t_a). A new phenomenological model by Gómez Ribelles (the GR model) of enthalpy relaxation based on the evolution of configurational entropy was used to simulate the experimental data to verify the applicability of the GR model to small molecular glass. The results indicated that a single set of GR model parameters only reproduced the corresponding experimental C_p(T) curve of D-sorbitol fairly well. It failed to find a set of GR model parameters as the material constant independent of the thermal history. In contrast with other phenomenological models, some parameters of the GR model remained unchanged. The model parameter sets obtained under longer annealing time show better predictive ability. In contrast to the continuous cooling process for D-sorbitol, the ratio between the mean value of the limit state parameter (δ) and the increment of specific heat capacity at T_g (ΔC_p(T_g)) apparently increases, but the increase is less than that of polymers. The results brought into question if the metastable limit state introduced by the GR model applied to small molecular glass systems.

Using Fourier transform near infrared (FT-NIR) spectroscopy, the characteristics and phase change mechanism of the phase change process for PMMA-SiO₂@PCM microcapsules were explored. We investigated changes in the microstructure of the microcapsules as well. The results show that the melting of paraffin molecules in the microcapsules is a process wherein the －CH₂ symmetric stretching vibration gradually increases and the asymmetric stretching vibration changes randomly. During the paraffin phase change process, the change in absorbance intensity is only half that of the shell materials. Additionally, NIR spectroscopy was used to analyze the core-shell structure and to monitor the phase change process for the microcapsules. The application of NIR spectroscopy to study the phase change process for microcapsule phase change materials has scientific significance and is of value to study the phase change mechanism for the determination of the most efficient phase change materials.

The solvent viscosity dependence of the photophysical and photochemical properties of tetra(tert-butylphenoxy)phthalocyaninato zinc(II) (ZnTBPPc) is presented. The fluorescence quantum yields (Φ_F) and Stern-Volmer′s constant (K_SV) for ZnTBPPc fluorescence quenching by benzoquinone in all the solutions followed a semi-empirical law that depends only on the solvent viscosity. Φ_F values vary between 0.08 in tetrahydrofuran (THF) and 0.14 in dimethylsulphoxide (DMSO). Triplet quantum yields (Φ_T) and lifetimes (τ_T) also exhibit clear solvent viscosity dependence with the values being higher in the most viscous solvents. The interaction of the ZnTBPPc triplet state with oxygen was found to be diffusion- controlled, but higher rate constants were observed in low-viscosity solvents like THF and toluene. Absolute values of singlet oxygen quantum yields (Φ_Δ) were determined, and the values are comparable in all the solvents, which is attributed to the proximity of the ZnTBPPc triplet energies in different solvents.

In this study, we found regular behavior, from a statistical point of view, in the intensities of rotational spectra for several organic and inorganic molecules at room temperature. Non-linear molecules, for which a common intensity behavior was derived, were especially interesting. We provided theoretical support for the obtained results based on the Boltzmann distribution. Boltzmann power laws were used to reproduce the statistical behavior of the intensities from the spectra of linear and non-linear molecules. We only used statistical arguments and no specific details of any molecule were used. Therefore, these results are applicable to a large class of atoms and molecules and the model is valid when considering similar conditions to those used in this study.

In this work, atmospheric cracking equipment was used to study the distribution of the main gas products of n-decane pyrolysis including hydrogen, methane, and ethylene between 973-1123 K and at different residence time of 0.5-2 s. The detailed mechanism for n-decane pyrolysis, which was composed of 1072 steps and 281 species, was automatically generated by the ReaxGen program that was developed in our laboratory. We thus carried out kinetic modeling and the results were compared with experimental observations. Using sensitivity analysis we identified the main reaction steps, the alkyl rearrangement and the β-cleavage reactions, which mostly influence the distributions of hydrogen, methane, and ethylene at atmospheric pressure and 973 K with a residence time of 1 s.

The adsorption behaviors of O and O₂ on charged and neutral Au₁₉ and Au₂₀ clusters were systematically investigated by density functional theory (DFT) with Dmol³ program. Our results indicate that the adsorption energies of O on the hollow sites of Au₁₉ are higher than those on Au₂₀; while those on the side-bridge sites of the Au₁₉ and Au₂₀ clusters are similar. For negatively charged clusters, the adsorption energies of O and O₂ are higher than those for neutral and positive clusters. The O―O bond lengths of the adsorbed O₂ on the Au₁₉ and Au₂₀ clusters with different charges show a similar trend to the adsorption energy, that is, the O―O bond lengths on Au₁₉^- are longer than those on the Au₁₉ and Au₁₉⁺ clusters. Population analysis shows that more electrons transfer to the adsorbed O and O₂ from the Au₁₉^- and Au-20 clusters, which indicates stronger interactions compared with the neutral or positive clusters. Charge density difference (CDD) analysis for O₂ on the Au₁₉ and Au₂₀ clusters suggests that electrons of the Au₁₉ and Au₂₀ clusters transfer to the π^* orbital of O₂, upon which the O―O bonds are activated. The dissociation reaction barrier of O₂ on Au₁₉^- is 1.33 eV, which is lower than those on Au₁₉ (1.86 eV) and Au₁₉⁺ (2.27 eV).

First-principles calculations based on density functional theory (DFT) and the periodical slab model were used to study the adsorption and dissociation of methanol on the perfect FeS₂(100) surface. The adsorption energy and the geometric parameters on the different adsorption sites showed that the Fe site was the most favorable adsorption site and O atoms were found to bind to Fe atoms. After adsorption, the C―O and O―H bonds of methanol were elongated and the vibrational stretch frequency was red shifted. The calculation results proved that methanol was prone to decomposition resulting in methoxy groups and hydrogen. We calculated the adsorption behavior of these methoxy groups and hydrogen on the FeS₂(100) surface and found that the Fe sites were also the most favorable adsorption sites. A possible decomposition pathway was investigated using transition state searching methods: first the O―H bond of methanol was decomposed producing the intermediate methoxy group and subsequently the C―H bond of the methoxy group was broken resulting in final products of formaldehyde and hydrogen.

We investigated the double-bond isomerization reaction of 1-hexene to cis-2-hexene on the surface of ZSM-5 zeolite using density functional theory with a 54T cluster model simulating the local structures of zeolite materials. We found that the double-bond isomerization proceeded by a mechanism that did not involve the bifunctional (acid-base) nature of the zeolite active sites but exclusively involved the Brønsted acid sites. According to this mechanism, 1-hexene is the first physically adsorbed onto the zeolite acid site resulting in the formation of a π-complex, and then the acidic proton of the zeolite transfers to a carbon atom of the double bond of the physisorbed 1-hexene. The other carbon atom of the double bond of the physisorbed 1-hexene bonds with the Brønsted host oxygen and yields a stable alkoxy intermediate. Thereafter, the Brønsted host oxygen abstracts a hydrogen atom from the C₆H₁₃ fragment and the C―O bond of the alkoxy intermediate is broken, which restores the zeolite active site and yields physisorbed cis-2-hexene. The proposed reaction pathway competes with the bifunctional pathway. The rate- determining step is the decomposition of the alkoxy intermediate with an activation energy of 134. 64 kJ·mol^-1. The calculated apparent activation energy for the isomerization reaction is 59. 37 kJ·mol^-1, which is in od agreement with the reported experimental value. These results well explain the energetic aspects during the double-bond isomerization and extend the understanding of the nature of zeolite active sites.

The geometries of ground and excited states of a series of ruthenium complexes [Ru(iph)(L)₂]²⁺(L=cpy (1), mpy (2), npy (3); iph=2,9-di(1-methyl-2-imidazole)-1,10-phenanthroline, cpy=4-cyano pyridine, mpy=4-methyl pyridine, npy=4-N-methyl pyridine) were optimized by the Becke′s three-parameter functional and the Lee-Yang-Parr (B3LYP) functional and unrestricted B3LYP methods, respectively. Time- dependent density functional theory (TD-DFT) method at the B3LYP level together with the polarized continuum model (PCM) were used to obtain their absorption and phosphorescent emission spectra in acetone media based on their optimized ground and excited-state geometries. The results revealed that the optimized structural parameters agreed well with the corresponding experimental results. The highest occupied molecular orbitals were localized mainly on the d orbital of the metal and the π orbital of the iph ligand for 1 and 2, and the npy ligand for 3, while the lowest unoccupied molecular orbitals were mainly composed of π^* orbital of the iph ligand. Therefore, the lowest-lying absorptions and emissions were assigned to the metal to ligand charge transfer (MLCT)/intra-ligand charge transfer (ILCT) transition for 1 and 2, and the ligand to ligand charge transfer (LLCT) transition for 3. The lowest-lying absorptions are at 509 nm (1), 527 nm (2), and 563 nm (3) and the phosphorescence emissions at 683 nm (1), 852 nm (2), and 757 nm (3). The calculation results show that the absorption and emission transition characteristics and the phosphorescence color can be changed by altering the π electron-donating ability of the L ligand.

The geometric structures and stabilities of small Zr_mOn (1≤m≤5, 1≤n≤2m) clusters were studied using density functional theory (DFT) calculations with the Perdew-Wang exchange correlation functional and the generalized gradient approximation (GGA). The lowest energy structures of all these clusters were obtained by the sequential oxidation of the small “core” zirconium clusters. In general, the O atoms prefer the bridge sites along the Zr_m skeleton. The ground-state structures of the (ZrO₂)₃ and (ZrO₂)₅ clusters are consistent with coordination number rules and bonding regularity. The fragmentation channels and fragmentation energies of the small zirconium oxide clusters were discussed. We found that the Zr_mO_2m-1 clusters (not including Zr₄O₇) had the largest fragmentation energy among the clusters with the same number of zirconium atoms.

Based on the density of the general theory, the structures of ziqzag graphene nanoribbons (ZGNRs) (N=17, N is the number of carbon chain) with nanoholes are optimized and then get the transport property of the electrons in these systems with different holes through the calculation. The results show that the conductance is not only related to the quantum confinement effect, but also confined by the symmetry of the hole and the configuration of the dia nal symmetry is larger than the longitudinal symmetry′s in the presence of a single-hole. In the case of two holes, the conduction of the system is advanced with the growth of the distance between the two holes because of the coupling effect. At the same time, we can get some quantum phenomenon which can be explained by the model of one- dimensional double barrier.

A fundamental electrochemical study of Si in Na₃AlF₆-LiF melts and electrowinning and electrorefining in a small-scale laboratory cell was conducted. Cyclic voltammograms showed that the reduction of Si proceeds by two successive electron transfers and the presence of the Si(II) species in the melt was confirmed. Galvanostatic electrolysis showed that the deposited silicon crystal does not form any dense or massive layer at the graphite cathode as other metals do, but it is generally dispersed in the deposit around the cathode. The co-deposition of Al and Si is possible when the reduction potentials are more negative than -1.8 V versus Pt. The purity of the deposited Si was higher than 99.9%. This study demonstrates the feasibility of very pure Si production by electrochemical methods.

The recurrent potential pulse (RPP) technique is an alternative and effective technique for redox stability measurement. We investigated the electrochemical redox stability of polypyrrole (ppy) films doped with sodium p-toluenesulfonate by RPP technique in this study. The reduction charge (Q_red) and the ratio of reduction and oxidation charges (Q_red/Q_ox) obtained from the switching potentials in aqueous solutions of H₂SO₄, Na₂SO₄, and NaOH were calculated to describe the reversibility of ppy at the applied potential windows. We found that the irreversible overoxidation strongly depended on the pH value of the supporting electrolytes and on the switching potentials. The onset of the overoxidation potential is 0.8 V in H₂SO₄ solution while it is only 0.5 V in Na₂SO₄ solution. In NaOH solution, overoxidation occurs at any potential indicating that the existence of OH^- ions is directly responsible for overoxidation.

Nano TiO₂ films were applied to the surface of stainless steel (SS) by sol-gel and hydrothermal crystallization using Ti(O(CH₂)₃CH₃)₄ as a precursor. The properties of the TiO₂ films were determined by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), and Auger electron spectroscopy (AES). The corrosion performance of the TiO₂ films was evaluated by electrochemical impedance spectroscopy (EIS) and polarization measurements. Anatase TiO₂ films prepared by hydrothermal crystallization at 170 °C showed similar crystallization to those prepared by conventional calcination at 450 °C. The TiO₂ prepared by the two methods were, however, obviously different from the surface structure and the material prepared by hydrothermal crystallization showed better anticorrosion performance in 3.5% (w) NaCl solution compared with the material prepared by calcination.

We produced a group of surfactin isoforms using Bacillus subtilis HSO121. The micellization activity properties such as surface and interfacial tensions, micropolarity, micelle size distribution and morphology of this group of surfactin micellar solutions were investigated by surface and interfacial tension, fluorescence, dynamic light-scattering (DLS), and freeze-fracture transmission electron microscopy (FF-TEM) measurements. With an increase in the chain length, we found that the surface and interfacial activities of the surfactins increased and the surfactins tended to form larger micelle aggregates.

The effects of charge number, diameter, surface charge density as well as concentration of macroions on the structure of a polyelectrolyte/surfactants complex were investigated using coarse- grained molecular dynamics simulation. We found that the macroions that had the same charge as the polyelectrolyte had no obvious effect on the structure of the polyelectrolyte/surfactants complex. However, the macroions with opposite charge to the polyelectrolyte can induce the release of surfactant from the polyelectrolyte and even lead to the complete disassembly of the polyelectrolyte/surfactants complex and the formation of a macroion/polyelectrolyte complex. The induction effect increases with an increase in charge number. For microions with the same charge number, smaller microions were found to cause desorption of the surfactant more easily. However the opposite effect was found for the diameter at a fixed charge density. The concentration of macroions also affects the structure of the complex greatly and the surfactants that are released from the polyelectrolyte increase with the macroion concentration and finally a macroion/polyelectrolyte complex with reversed charges is formed.

A novel efficient photoscatalytic system Eosin Y/Pt/SiO₂ for photocatalytic reduction of water to hydrogen under visible light irradiation was constructed. The effects of parameters, such as the surface physical property of SiO₂ (i.e., specific surface area), method of mixing Eosin Y and SiO₂, and light intensity on catalyst properties for hydrogen evolution were investigated systemically. With increase of SiO₂ specific surface area, the rate of hydrogen evolution increased. Either over high or low intensive irradiation is detrimental to obtain high quantum efficiency for hydrogen evolution. Compared to the Eosin Y adsorbed on SiO₂ by an impregnation method, the composite system in which Eosin Y mixed with SiO₂ physically in situ displayed higher rate and superior stability of hydrogen evolution.

Fluorine-modified nanosized TiO₂ (F-TiO₂) was prepared by a facile precipitation-fluorination- reflux method. Characterizations of transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and diffuse reflectance spectroscopy (DRS) were carried out to investigate various properties of the as-prepared F-TiO₂ powder. We found that the F-TiO₂ particles were small (5-8 nm) and ellipsoidal in shape. The presence of fluorine not only suppressed the formation of a brookite phase, but also improved the crystallinity of the anatase phase. The fluorine atoms were mainly distributed on the surface of TiO₂, and existed in both forms of chemical-adsorption and interstitial-doping. Compared to pure titania, the fluorine-modified TiO₂ powder showed a much higher methyl orange (MO) degradation efficiency under UV light and under visible light. Through the experiments of alkaline washing and heat treatment, we found that the increased MO degradation rate under visible light irradiation was caused by the enhanced self- degradation of the dye over the surface-modified TiO₂.

A series of alumina supports stabilized by alkaline earth metals and zirconia were prepared by the peptizing method. Pd-Rh close-coupled catalysts supported on modified alumina were prepared by the impregnation method. The supports were characterized by low temperature nitrogen adsorption-desorption method, X-ray diffraction (XRD), and NH3-temperature programmed desorption (NH3-TPD). For the catalysts, H₂-temperature programmed reduction (H₂-TPR) and X-ray photoelectron spectroscopy (XPS) were carried out. We also carried out catalytic activity tests for C₃H₈ conversion. Results show that the addition of alkaline earth metals increases the surface area of the supports and the surface area of Sr-Zr-Al reaches 164 m²·g^-1 after calcination at 1000 °C for 5 h. The introduction of alkaline earth metals into the ZrO₂-Al₂O₃ supports also improves their catalytic activity toward propane oxidation and the activities of the Pd-Rh catalysts containing alkaline earth metals are higher than that of the catalyst prepared with a ZrO₂-Al₂O₃ support.

A series of CuO-Ce_0.6Zr_0.4O₂ catalysts with different contents (0-25%, w) of CuO were prepared by microwave heating decomposition and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), N₂ adsorption-desorption (BET), and temperature-programmed reduction with hydrogen (H₂-TPR). The activities of the catalysts for CO oxidation were evaluated using a microreactor-gas chromatograph system. The results show that the CuO-Ce_0.6Zr_0.4O₂ catalyst exhibits the best catalytic activity for CO oxidation at a CuO content of 15%. Three copper species are present in the catalysts, i.e., highly dispersed, small and large CuO particles. The highly dispersed and small CuO particles are responsible for the promotion of catalytic activity while the large CuO particles inhibit catalytic activity.

A novel rare earth double perovskite-type catalyst (La₂CoAlO₆) was prepared by the sol-gel method using citric acid as complex agent. The catalyst was characterized by X-ray powder diffraction (XRD), H₂-temperature-programmed reduction (H₂-TPR), specific surface area (BET), scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy, and magnetic property measurement. This catalyst was evaluated for methane combustion. The results showed that a single-phase rare earth double perovskite oxide La₂CoAlO₆ could be formed by calcination at 1100 °C for 3 h. La₂CoAlO₆ gives od catalytic activity for methane combustion. It has a light-off temperature (T₁₀) of 434.1 °C and a total conversion temperature (T₉₀) of 657.4 °C. Compared with the single rare earth perovskite-type oxides LaCoO₃ and LaAlO₃, the T₁₀ decreased by 56.5 and 138.2 °C, and T₉₀ decreased by 84.6 and 108.9 °C, respectively. The FT-IR results indicate that all the synthesized oxides possess perovskite-type structures. Furthermore, the La₂CoAlO₆ samples showed excellent catalytic activity for methane combustion, which could be related to the decrease in reduction temperature that was observed in the H₂-TPR experiments. This was probably because of the increased oxygen mobility that was promoted by the presence of aluminum. In addition, the rare earth double perovskite-type oxide La₂CoAlO₆ has a platelet morphology and is resistant to sintering. We also found that the double perovskite oxide La₂CoAlO₆ had special magnetic properties.

Cu(I)Y zeolites with different degrees of ion exchange were prepared by solid state ion exchange (SSIE) and liquid phase ion exchange (LPIE). The surface acidity of the Cu(I)Y zeolite was characterized by adsorbed pyridine infrared spectroscopy (Py-IR) and the adsorbents desulfurization capabilities were evaluated by a fixed-bed adsorption experiment. We observed that after modification using different ion exchange methods the Cu(I)Y zeolites retained the structure of the Y zeolite completely. The amount of exchanged Cu⁺ and the surface acidity including the Brönsted (B) acid content and the Lewis (L) acid content greatly affected the adsorption desulfurization process. After SSIE and with an increased degree of ion exchange the B acid gradually transformed to the L acid as a result of an improvement in the adsorption capacity. The results revealed that decreasing B acid content might be the essiential reason for the evidently improved adsorption desulfurization activity for the Cu(I)Y zeolites prepared by different ion exchange methods.

The adsorption performance of nanoporous carbon (NC) and ethylenediamine-modified nanoporous carbon (NC-EDA) toward Hg²⁺ ions was investigated in an aqueous solution. The NC material exhibited a relatively high adsorption capacity for Hg²⁺ ions, and the adsorption capacity was improved significantly by ethylenediamine modification. After thermal-treatment at 873 K, the adsorption capacity of the NC-EDA material was still relatively high. Based on various characterization results, we propose that the presence of abundant functional groups (i.e., －COOH, －OH) on the surface of the NC materials is beneficial for the introduction of a large number of amino functional groups resulting in the presence of abundant basic N-containing species on the surface of the NC materials. These basic species can interact with mercury ions and thus significantly improve the adsorption capacity of the carbon material.

Poly(phenylenevinylene) (PPV) is one of the most efficient electroluminescent conjugated polymers and has the potential to be commercialized as important components in full-color flat panel displays. Here, we report an alternative synthetic route to the commercially available PPV derivative Super Yellow PPV (SY PPV) using 2-bromo-1,4-xylylene diacetate as a novel starting material. The intermediates, monomers, and the polymer were fully characterized by nuclear magnetic resonance (NMR) and elemental analysis. The SY PPV film shows an absorption maximum at 434 nm and an absorption onset at 510 nm with an optical bandgap of ca 2.44 eV. The photoluminescent and electroluminescent maximum of SY PPV are around 516 and 552 nm, respectively. The SY PPV obtained via this new synthetic route exhibits improved electroluminescent properties, a turn on voltage of over 2.4 V, a luminance maximum exceeding 49000 cd·m^-2, and a maximum luminous efficiency (LE) of 21 cd·A^-1 compared with the SY PPV prepared by the traditional route (16-18 cd·A^-1).

α(β)-tetra-(methoxy-phenoxy)-zinc phthalocyanine are synthesized by employing 3(4)- nitrobenzene-1,2-dicarbonitrile as precursors. They are characterized by spectrum methods and elemental analysis. The UV-Vis spectrum, photoluminescence spectra of spin-coated film and solid pellet are compared. The electroluminescent devices are fabricated by using spin coating. The results indicate that the fluorescence of solid phthalocyanine has a red-shift of more than 145 nm compared to that in solution. The fluorescences are broader in solid state than that in solution. The fluorescence of β-substituted phthalcyanines has a more red-shift than α-substituted phthalcyanines. The electroluminescent spectra around 856 and 862 nm are consisted with the photoluminescence spectra of spin-coated film. The shorter inter-molecule space leads to the large red-shift of the fluorescence.

Sr_1.99MgSi₂O₇:Eu_0.01 samples were prepared in four steps under air, a reducing atmosphere, air again, and a reducing atmosphere again. The samples prepared in air showed both Eu²⁺ and Eu³⁺ em- ission while the samples prepared in a reducing atmosphere showed Eu²⁺ emission with a long afterglow and two thermoluminescence (TL) bands. However, only one TL band was observed for the sample prepared directly in the reducing atmosphere. Hole traps were created during the synthesis in air and were preserved during the reducing synthesis. These hole traps are different from the electron traps created by a reducing atmosphere. The hole traps and the electron traps result in two TL bands.

We prepared PAM/ZnO micro-nano arrays on indium tin oxide (ITO) conductive films based on poly(ethylene terephthalate) (PET) substrates (PET/ITO) by a low cost and low temperature chemical solution approach. The morphology and crystal structure of the nanorod arrays were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results show that the ordered arrays of the ZnO and PAM/ZnO arrays grew vertically on the substrates and revealed that the nanorods grew along the [0001] direction of the ZnO crystallites. SEM images showed that most of the ZnO arrays had an average diameter of 150 nm and their typical length was about 3 μm. The optical properties of the ZnO and PAM/ZnO micro-nano arrays were characterized by photoluminescence at room temperature. The growth mechanism of the PAM/ZnO arrays and their possible application in flexible optoelectronic devices are discussed. Defect peaks of the blue peak at 457 nm and the green peak at 530 nm were observed in the photoluminescence (PL) spectrum of the ZnO micro-nano arrays in the absence of PAM. The blue and green emissions are attributed to electron transitions from the extended state Zn_i to the valance band and from the conduction band to antisite oxygen (O_Zn), respectively. The PAM/ZnO arrays only had a UV peak at 400 nm, and this was caused by electron transitions from the interstitial Zn (Zn_i) to the valance band. Flexible PAM/ZnO devices with od diode characteristics are suitable for flexible optoelectronic applications.

A strategy combining structure alignment and comparation, target cluster, and invert-docking screening were undertaken to detect the potential bioactivities of several isomalabaricane triterpenoids that were extracted from sponge. The prediction results revealed that the chemicals underwent myocardial ischemia treatment and had antineoplastic bioactivities. Enzymatic bioassays showed that epidermal growth factor receptor (EGFR), focal adhesion kinase (FAK), insulin-like growth factor 1 receptor (IGF1-R), c-Src kinase, and vascular endothelial growth factor receptor 2 (VEGF-R2) were potential targets for these compounds. They had IC₅₀ values ranging from 0.41 g·m^-3 (0.41 μg·mL^-1) to 9.8 g·m^-3 (9.8 μg·mL^-1), which is meaningful for the use of these marine natural products as leads for further modifications to new agents. Ligand-target binding mode with these compounds were undertaken and indicated that the four studied chemicals bound well with the targets.

This study developed a mutual recognition of the proteins based on molecular classification, data mining strategies and the statistical clustering method, which was applied to study and classify clusters of coenzyme-A (CoA) binding proteins with their binding patterns extracted by using Pocket1.0 program. Several strategies have been evaluated for the accuracy of the system analysis and the two-step clustering method has been shown to be the best. The results revealed that the known CoA binding proteins can be clustered into three groups by using this approach. The designed classification coefficient was used effectively to identify the critical features for classification. The results show that both hydrogen bonds and hydrophobic interactions are important in all three clusters and that quite a few important residues related to biological activities are involved in the formation of hydrogen bonds. The classification of these interactions and the discovery of the characteristics and differences between the three clusters will have some utility for the design of specific a nists and anta nists.

Transparent conductive Al-doped ZnO (AZO) and Si-codoped AZO (AZO:Si) films were deposited on square quartz substrates by radio frequency (RF) magnetron sputtering. The effect of distance between the substrate and target (D_st) and the effect of co-doping Si on the electrical and optical properties of the AZO films were systematically investigated. The resistivity, carrier concentration, and mobility were found to be strongly dependent on the D_st values. With a decrease in D_st, the carrier concentration and mobility increased significantly, which resulted in improved conductivity. The lowest resistivity of 4.94×10^-4 Ω·cm was obtained at a D_st of 4.5 cm, and this was associated with a carrier concentration of 3.75×10²⁰ cm^-3 and a mobility of 33.7 cm²·V^-1·s^-1. X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) spectroscopy, and grain boundary scattering models were used to analyze the relationship between the carrier concentration and the mobility at different deposition (D_st) values. Transmittance spectra showed an average transmittance of >93% in the visible-near infrared range for all the samples and a blue shift of the absorption edge with a decrease in D_st. AZO:Si films had high-conductance and high-transmittance optical properties compared with AZO films, and they had better resistivity stability than the AZO films when exposed to a hot and damp atmosphere, which is practically meaningful.

PbS semiconductor quantum dots with different particle sizes were successfully prepared by the colloidal chemistry method according to the theory of fast nucleation at high temperature and slow growth at low temperature. Sodium sulfide was used as a sulfur precursor because it is odorless and is less noxious, which allows it to be classified as a green precursor. Oleic acid was used as a stabilizing agent to control the particle growth and it thus assisted in the formation of monodisperse PbS quantum dots. The crystalline structures, morphology, and particle size of the quantum dots were characterized by powder X-ray diffraction and high-resolution transmission electron microscopy. The quantum size effect of the PbS nanoparticles was analyzed by visible near-infrared (Vis-NIR) absorption spectroscopy. The mean size of the PbS quantum dots increased with a decrease in the concentration of oleic acid. A possible growth mechanism for the PbS nanoparticles was also discussed.

Three-dimensional (3D) ld nanoflowers of 60-80 nm in diameter were successfully synthesized using polyvinyl pyrrolidone (PVP) as both a protecting agent and a reducing agent in alkaline aqueous solutions. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) images revealed that many antennae of 10-15 nm existed on their surfaces. X-ray diffraction (XRD) pattern suggested face-centered cubic (fcc) structures for these ld nanoflowers. The selected area electron diffraction (SAED) pattern of a single ld nanoflower indicated polycrystal characteristics. We found that there were three key stages in the growth of the ld nanoflowers: primary nanocrystals agglomerated to form multipod-like nanoparticles, and then the multipod-like nanoparticles aggregated into loose flower-like nanoparticles that ultimately grew into compact ld nanoflowers through Ostwald ripening. During the synthesis of ld nanoflowers, the molar ratios of PVP/HAuCl₄ at fixed HAuCl₄ and NaOH concentrations mostly influenced the morphologies of the final products. Therefore, a proper molar ratio of PVP/HAuCl₄ and a suitable NaOH concentration were essential for the synthesis of typical ld nanoflowers with controlled sizes and antenna architectures.

We prepared large-area, vertically aligned Sn₂S₃ one-dimensional nanostructure arrays using tin and sulfur powder as reactants on a lead-plated silicon substrate by chemical vapor deposition (CVD). Scanning electron microscopy (SEM) showed that these Sn₂S₃ nanowires had diameters around 100 nm and lengths of several microns. X-ray diffraction (XRD) results indicated that the obtained Sn₂S₃ nanowires were composed of an orthorhombic phase with very od crystallinity, and grow in the [002] direction. Ultraviolet-visible (UV-Vis) diffuse reflectance spectroscopy revealed that they are direct-bandgap semiconductors with a bandgap of 2.0 eV. The growth of Sn₂S₃ nanowires is verned by the vapor-solid (V-S) growth mechanism, and the Pb atoms present in the lattice as substitutional atoms instead of on the tips of nanowires as catalyst particles.

BaTiO₃-BaFe₁₂O₁₉ core-shell structure particles were obtained using the homogeneous coprecipitation method. The effects of temperature, molar ratio of urea to metal ions (R), and BaTiO₃ concentration on the morphology and structure of the core-shell particles were investigated. The mechanism of formation for the BaTiO₃-BaFe₁₂O₁₉ core-shell structure particles and their magnetic property were also discussed. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) were used to characterize the morphology and structure of the BaTiO₃-BaFe₁₂O₁₉ precursor core-shell structure particles and the BaTiO₃-BaFe₁₂O₁₉ core-shell structure particles. A vibrating sample magnetometer (VSM) was used to characterize the magnetic property. The results indicated that the obtained sample possessed an integrated and smooth shell of about 10 nm in size and the metal ions precipitated completely after homogeneous coprecipitation when the sample was synthesized under the following conditions: 100 °C, R=180, and a BaTiO₃ concentration of 2.5 g·L^-1. A large amount of free particle impurities appeared if the temperature and R value were too high. The shell thickness of the BaTiO₃-BaFe₁₂O₁₉ precursor core-shell structure particles tended to decrease as the BaTiO₃ concentration increased. The BaFe₁₂O₁₉ phase in the shell began to form when the calcination temperature reached 900 °C. The mechanism of formation included the formation of BaFe₂O₄ by the reaction of crystalline α-Fe₂O₃ and BaCO₃ initially, and this was followed by the reaction of BaFe₂O₄ and α-Fe₂O₃ to form the final BaFe₁₂O₁₉. As the temperature increased to 1000 °C, a complete BaFe₁₂O₁₉ shell was obtained. The saturation magnetization and coercivity of the BaTiO₃-BaFe₁₂O₁₉ core-shell structure particles increased and decreased from 16.5 to 39.5 A·m²·kg^-1 and from 340 to 316 kA·m^-1, respectively, as the calcination temperature increased from 900 to 1000 °C.

Fe₃O₄ nanoparticle-graphene oxide (M ) composites were prepared by chemically binding carboxylic acid-modified Fe₃O₄ nanoparticles to polyethylenimine-functionalized graphene oxide ( ). The structure, morphology, and magnetic properties of the composites were characterized by transmission electron microscopy (TEM), atomic force microscopy (AFM), X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA), and vibrating sample magnetometry (VSM). The results show that the Fe₃O₄ nanoparticle content in the M composites can be easily controlled by changing the ratio of Fe₃O₄ nanoparticles to in the reaction mixture. The M composites obtained are superparamagnetic with high saturation magnetization, which can potentially be applied in magnetic targeted drug delivery, gene transport, magnetic resonance imaging, bioseparation, and magnetic guided removal of aromatic contaminants in waste water and in other fields.

Polyacrylamide (PAAm) hydrogels with very high mechanical strength were prepared using radiation-peroxidized micelles that were formed by surfactant molecules as initiating and crosslinking centers. PAAm/Fe₃O₄ nanocomposite hydrogels were obtained by introducing Fe₃O₄ nanoparticles into PAAm hydrogels through an in situ chemical co-precipitation method. Scanning electron microscopy (SEM) investigations showed that the nanoparticles were homogeneously distributed and the particles were about 30 nm in size. X-ray diffraction (XRD) analysis showed that the obtained nanoparticles were spinel Fe₃O₄. The PAAm/Fe₃O₄ nanocomposite hydrogels showed superparamagnetism. The ferrogels also had od mechanical properties, the elongation at break of some gels could be as high as 1200% and the maximum tensile strength was about 0.10 MPa, and they exhibited very od shape recoverability.