The isothermal gas-liquid phase boundary lines and critical curve were determined for the water+methane system. Experiments were performed in a high-pressure volume-variable autoclave with a sapphire window and magnetic stirring. The temperature range was from 433.0 to 633.0 K and pressure from 30.00 to 300.00 MPa. Henry coefficients of dilute methane solutions were determined; the results show that these coefficients decrease with increasing temperature in the range from 433.0 to 603.0 K. The equilibrium gas-liquid ratios, partial molar solution enthalpy, and partial molar solution entropy were also calculated. The results show that the difference in the cohesive energy density between methane and water is very large.

The performance of density functional theory (DFT) with and without dispersion energy correction for describing van der Waals (vdW) systems is evaluated by calculating the crystal structure, lattice energy, and elastic properties of solid methane. The results obtained from DFT with different exchange-correlation functionals (including some hybrid functionals) and from DFT with dispersion energy correction (DFT-D) methods are compared with experimental values. Although the DFT-D methods typically perform better than the standard and hybrid DFT functionals, some of them overcorrect the vdW interaction in solid methane. Thus, one must be cautious when using DFT-D methods.

Nicotinic acid and isonicotinic acid were utilized to react with Co(NO₃)₂ in N,N'- dimethylformamide (DMF) in solvothermal conditions respectively, and resulted in three new coordination polymers: [Co₂(μ₂-H₂O)(nicotinic acid)₄·(DMF)] (1), [Co₂(isonicotinic acid)₄·(DMF)] (2), and [Co(isonicotinic acid)₂·(DMF)] (3). Single crystal X-ray diffraction (XRD) and elemental analysis were performed to obtain structural information on these compounds. Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), and N₂ isotherm analysis were utilized to investigate the pore stability of the three compounds. The above experiments reveal that compound 1 has a diamond-like topology, and the one-dimensional (1D) channels in compound 1 are stable after the removal of DMF molecules. Compounds 2 and 3 were synthesized at 100 and 160 °C by the coordination of isonicotinic acid with Co(II), respectively. The coordination modes of isonicotinic acid to Co(II) are completely different in the two compounds, which lead to two different crystal structures. The 1D channels in compounds 2 and 3 were not stable after the removal of DMF molecules.

We study the ion associations in magnesium nitrate solution by Raman spectroscopy. Utilizing the excess spectra and peak decomposition, we analyze the －OH stretching and NO₃^- symmetric stretching regions. Analysis of the －OH stretching region demonstrates that the amount of water molecules in the first hydration shell of the anion follows a linear relationship in the low concentration range (<2.3 mol·kg^-1), but deviates from this linear relationship at high concentrations (>2.3 mol·kg^-1). The contact ion-pairs at high concentration result in the nonlinear variation. In the NO₃^- symmetric stretching region, the contact ion-pairs and solvent separated ion pairs exist in the Mg(NO₃)₂ concentration region of 0.23-4.86 mol·kg^-1. From a global fitting of the Raman spectra over the whole concentration region, we deduce that the concentration of ion pairs varies. When the Mg(NO₃)₂ concentration is below 2.3 mol·kg^-1, the relative amounts of all ion-pairs increase with the concentration. However, above this concentration, the relative amount of contact ion pairs increases sharply, and solvent separated ion pairs either decrease or increase in their slower rate, until the Mg(NO₃)₂ concentration is 3.5 mol·kg^-1, and above this concentration the relative amount of one kind of solvent separated ion-pair does not change.

The photoreaction mechanism of L-valine optical isomerization was studied by the density functional theory (DFT) and ab initio molecular orbital theory. The geometric parameters of reactant, product, intermediates, and transition states on the reaction paths in S₀ and T₁ states were optimized at the level of B3LYP and MP2 methods and 6-311++G(d, p) basis sets and the reaction energy barriers were obtained by the same methods. The equilibrium geometries on the S₁ state of valine were also optimized by the method of time dependent density functional theory (TD-DFT) with B3LYP/6-311++G(d, p) level. Through the analysis of each stationary point geometric feature on the reaction path, the photoreaction mechanisms of L-valine optical isomerization were proposed in which the whole reaction was accomplished through hydrogen transfer with the help of carbonyl O or amino N atom in excited state. Furthermore the effect of solvent on the reaction mechanism of isomers was discussed by the method of polarizable continuum model (PCM) of self consistent reaction field theory.

Ab initio calculation was performed on the model peptide compound alanine dipeptide. The population of the secondary structures and the corresponding potential energies of alanine dipeptide were investigated. Normal mode analysis was performed on the amide vibrational modes, which are known to be quite sensitive to the molecular structure, and the correlation between the vibrational feature and the molecular structure was then revealed. The results show that alanine dipeptide has a minimum potential energy when the backbone dihedral is positioned at Φ/Ψ =-80°/80° , which can be denoted as a C_7eq conformation. It is also possible to form the secondary structures with β sheet, PP_II, C₅, and C₇ conformations for their low potential energies. The vibrational parameters of the 3N-6 vibrational motions were obtained through normal mode analysis. The amide vibrational modes were then assigned by the potential energy distribution analysis. The amide-I mode, mostly consisting of backbone C＝O stretching, was introduced for the prediction of the secondary structure of alanine dipeptide. The correlation between the amide-I vibrational parameters and the molecular structures is then demonstrated. Thus is a new way for the prediction of structural features of peptide and protein systems at the chemical bond level.

A series of chiral anatase (101) nanotubes (NT), which we refer to as (n,0), (0,m), and (n,m), can be formed by rolling up two-dimensional periodic anatase TiO₂ (101) single layer sheets. Optimized parameters of the atomic and electronic structures of these nanotubes have been calculated using a tight-binding density functional theory method (DFTB). Their band gaps (E_g) and strain energies (E_s) have been analyzed as functions of NT diameter. Except for (6,0), the strain energy and the band gap of all the nanotubes of various chirality decrease as the diameter increases. We also find that the strain energy increases first and then decreases rather than varying monotonically with almost constant band gap when n/m ranges from zero to infinitely large.

Recent studies have demonstrated that a simple ketone [acetone, (CH₃)₂C＝O)] reacts with the Si(100) surface in a [2+2] C＝O cycloaddition or by α-H cleavage to form Si―C and/or Si―O σ-bonds. To understand the reactivity of carbonyl compounds bearing different substitutes, the [2 + 2] C＝O cycloaddition and α-H cleavage of carbonyl compounds CH₃COR (R=CH₃, H, C₂H₅, C₆H₅) on Si(100) surface have been investigated using density functional theory at the B3LYP/6-311 ++ G(d,p)//6-31G(d) level. Our calculation results reveal that: (1) both cycloaddition and α-H cleavage corresponds to very low energy barriers (lower than 25 kJ·mol^-1), and the energy barrier for cycloaddition is slightly higher than α-H cleavage; (2) the substituents on the carbonyl compound [CH₃COR] has only a minor influence on the energy barrier; (3) the α-H cleavage reactions are thermodynamically and kinetically more favorable than cycloadditions; (4) for the α-H cleavage of butanone, reactions at C1 and C3 positions are competitive. These findings suggest that the reactions of ketone derivatives with Si(100) surface will generate multiple products.

The structures and hydrogen storage properties of two stable B₁₂Sc₄ and B₁₂Ti₄ clusters have been investigated using ab initio calculations. No metal atom clustering occurs in the clusters. The B₁₂Sc₄ hosts 12 H₂ to achieve 7.25% (mass fraction) hydrogen storage capacity with an average binding energy (ABE) of -10.4 kJ·mol^-1 per H₂, while the B₁₂Ti₄ can only host 8 H₂ (4.78%, mass fraction) with a higher ABE (-50.2 kJ·mol^-1 per H₂). High hydrogen pressure is needed for B₁₂Sc₄ to hold 12 H₂, even at 77 K. Electronic structure analysis indicates that the Kubas interaction in the B₁₂Ti₄-nH₂ complex is much stronger than that in the B₁₂Sc₄-nH₂ complex.

Based on spin-polarized density functional theory and generalized gradient approximation (DFT-GGA) calculations, the coverage-dependent adsorption of X bimetallic clusters (X=Pt-Au, Au-Au) on the (3 × 2) TiO₂(110) surface has been investigated utilizing periodic supercell models in the absence of oxygen vacancy sites. Only the ground-state structures corresponding to the given coverage patterns (θ= 1/6-1 ML) for X clusters are discussed in this work. The unambiguous results reveal that the adsorption energies increase with coverage up to 1/2 ML and then decrease except for when saturated coverage is reached. According to the interaction with X clusters, it is more feasible at all coverage levels to create a monolayer film of Pt-Au bimetallic clusters on the TiO₂(110) surface than it is to create a monolayer of Au- Au clusters, even though the adsorption energy of the Pt-Au/TiO₂ adsorption system is smaller in comparison with that of the Au-Au/TiO₂ system. Importantly, especially for the half and saturated coverages, there is a broadening of X peaks overlapping with the TiO₂ state ranging from -3.0 eV to the Fermi level, suggesting a strong interaction between the surface and bimetallic cluster. Also of particular interest is the adsorptive mechanism where the X-TiO₂ interaction is the main driving force at the initial stage of the adsorption process, whereas the X-X interaction controls the process as the coverage increases.

A periodic interaction model was proposed for the copper-iron layered double hydroxides, Cu₃Fe-LDHs-yH₂O(y=0-2). Based on density functional theory, the geometry of Cu₃Fe-LDHs-yH₂O was optimized using the CASTEP program. The distribution of NO₃^- and H₂O in the interlayer and the supermolecular interaction between host and guest was investigated by analyzing the geometric parameters, hydrogen-bonding, charge populations and stepwise hydration energy. Results showed that when NO₃^- and H₂O were inserted into the layers of Cu₃Fe-LDHs, there was strong supramolecular interaction between the host layer and the guest, including hydrogen-bonding and electrostatic interaction. Hydrogen-bonding was superior to the electrostatic interaction in the hydration process. The strength of hydrogen bonding was Layer-Anion(L-A) type hydrogen bonding＞Anion-Water(A-W) type hydrogen bonding＞L-A type hydrogen bonding＞Layer-Water(L-W) hydrogen bonding＞ Water-Water(W-W) type hydrogen bonding. In Cu₃Fe-LDHs-yH₂O, the interlayer distance decreased slightly and then increased significantly with an increase in the number of interlayer water molecules. The Cu-O octahedral forms were stretched gradually, because the Jahn-Teller effect of Cu²⁺ increased. The absolute value for the hydration energy decreased gradually with an increase in the number of water molecules. This suggested that the hydration of Cu₃Fe-LDHs reached a definite saturation state. The geometry parameters of Cu₃Fe-LDHs-1H₂O is close to the ideal hexa nal, the metal distortion of layer is the weakest and the stability is the strongest, interlayer distance matchs with the experimental value, so the Cu₃Fe-LDHs-1H₂O is a stable configuration.

Using plane wave pseudopotential methods based on density functional theory, the unit cell volumes, the electronic densities of states, the bond orders, the charge populations, and the formation enthalpies of Mg_2-xAl_xNiH₄ (x=0, 0.125, 0.25) alloys were calculated. By analyzing atom bonding and structural stability, the effects of partially substituting Al for Mg on the structure and hydrogen storage property of the alloys and their hydrides were investigated. It was shown that the unit cell volume of the Mg₂Ni alloy decreases with the increase of Al content; the decreased unit cell volume hinders the incorporation of hydrogen atoms, thus reducing the hydrogen storage capacity. For Mg_2-xAl_xNiH₄ (x=0, 0.125, 0.25) hydrides, the Mg-H and Al-H interactions are much weaker than the Ni-H interaction. However, the Ni-H interaction is weakened and the hydride enthalpy of formation decreases with increased Al content. Although the stability of the hydride structure is weakened, hydrogen desorption kinetics for the Mg₂Ni hydride can be improved with the partial substitution of Al for Mg.

The electronic structures and absorption spectra of indoline dyes containing different donors (ID1-ID3) were investigated by density functional theory (DFT) and time-dependent DFT, at the B3LYP and PBE1PBE levels, respectively. The effects of the donor moieties on the molecular structures, absorption spectra, and photovoltaic performance have been compared. The results indicate the increase in the number of phenyl groups in the donor decreases the highest occupied molecular orbital-the lowest unoccupied molecular orbital (HOMO-LUMO) energy gap and red-shifts the absorption band. This is related to the increased conjugation from ID1 to ID2 and ID3. The absorption spectra and LUMO energy level act as two criteria for the photovoltaic performance of a dye by determining the light harvesting efficiency and charge injection process, respectively. Considering the above two factors' contribution to the performance of a photovoltaic cell, ID3 with a long absorption band and high extinction coefficient, as well as a favorable LUMO energy level has been confirmed theoretically to be the best dye of ID1-ID3, which is consistent with experiment results.

The gas-phase reactions of YS⁺ (¹Σ⁺, ³Φ) with an S-transfer reagent (COS), YS⁺+COS→YS₂⁺+CO, were studied using density functional theory at the B3LYP/6-311+G* level. Four parallel reaction pathways were identified on both the ground- and excited-state surfaces. The mechanisms and the geometrical change trends on the different surfaces are quite different, except in the case of one reaction channel. The experimentally observed endothermic feature of the formation of YS₂⁺ can be attributed to three reaction paths, A, B, and C, with calculation barriers of 28.3, 140.5, and 120.2 kJ mol^-1, respectively, on the ground singlet surface. Our calculation results show that the title reactions have no two-state reactivity and the exothermic feature of the YS₂⁺ cross-section observed in the experiments is attributed to reaction of the residual excited-state of YS⁺ in the reactants.

Highly stable Li(Ni_1/3Co_1/3Mn_1/3)_1-xZn_xO₂ (x=0, 0.02, 0.05) cathode materials doped with Zn are synthesized by solid-state reactions with co-precipitated precursors. Cyclic voltammetry (CV) curves reveal that the potential difference between oxidation and reduction decreases to 0.09 V, and from electrochemical impedance spectra (EIS) curves, the impedance of LiNi_1/3Co_1/3Mn_1/3O₂ cathode materials is reduced from 266 to 102 Ω. The diffusion coefficients of Li⁺ ions in intercalation processes increase from 1.20×10^-11 to 2.54×10^-11 cm²·s^-1. Li(Ni_1/3Co_1/3Mn_1/3)_0.98Zn_0.02O₂ is stable at 0.3C (constant charge/discharge) at a high cut-off potential of 4.6 V vs Li/Li⁺. It has a second discharge capacity of 176.2 mAh·g^-1 at 0.3C and 142 mAh·g^-1 at 3C, and keep almost no decay after 100 cycles at room temperature. Furthermore, its average capacity loss per cycle at 55 °C is 0.20%, which is lower compared with 0.54% for LiNi_1/3Co_1/3Mn_1/3O₂ and 0.38% for Li(Ni_1/3Co_1/3Mn_1/3)_0.95Zn_0.05O₂ after 100 cycles. The improved electrochemical stability of Zn-doped LiNi_1/3Co_1/3Mn_1/3O₂ is attributed to the reduced electrode polarization and impedance values, and an increased Li+ ion diffusion coefficient.

Potato starch, as an extensive biomass with natural globular structure, had been used to prepare microporous carbon microspheres by the promoting effect of H₃PO₄ on the pyrolysis of starch and the activation of KOH. Pore structure of samples was characterized by nitrogen adsorption/desorption at 77 K, and the results showed that micropores were the major component in samples. The micropore structure of samples was believed that it would afford enough accessible surfaces for capacitive storage. After the observation using scanning electron microscopy (SEM), it could be seen that the globular shape of starch was completely remained in the following carbonization and activation procedures, which was believed that H₃PO₄ played an important role in the process. The following Fourier Transform Infrared Spectrometer (FT-IR) characterization confirmed that the acceleration effect of H₃PO₄ on starch pyrolysis. The results of electrochemical measurement in 6 mol·L^-1 KOH electrolyte showed that the product had excellent capacitive performances. Its specific capacitance was as high as 363.6 F·g^-1 at a current density of 50 mA·g^-1. And it exhibited excellent rate capability, which manifested that the cyclic voltammetry (CV) curve still remained rectangular and highly symmetric shape even when the scan rate reached as high as 300 mV·s^-1.All the results demonstrate that the potato starch-based microporous carbon is a promising electrode material for high performance electrochemical capacitors.

We investigate the electrodeposition of gallium metallic precursor on gallium and Cu/In substrates from acidic aqueous solutions. The effect of the supporting electrolyte and the solution pH value for the electrodeposition of Ga is investigated by cyclic voltammetry. During Ga electrodeposition, gallium gradually diffuses into the film, and reacts with CuIn alloy to produce CuGae₂ at the Cu/In interface. We use triethanolamine to protect the Cu/In and Ga films from being oxidized, and thus this improves the current efficiency of Ga-electrodeposition. The Cu-In-Ga films are annealed in an Se atmosphere to produce In_1-xGa_xSee₂(CIGS) thin films with high quality, and the efficiency of the solar cell prepared using these films is 9.42%.

The corrosion behavior of reinforcing steel in simulated concrete pore solutions with and without corrosion inhibitors was studied by electrochemical techniques and scanning electron microscopy (SEM). A combined inhibitive effect of sodium D-gluconate, Na₂MoO₄ and thiourea on restraining the corrosion of reinforcing steel immersed in the solution was observed. This result showed that there was a synergetic effect among the three agents in corrosion prevention. After adding the compound inhibitor (750 mg·L^-1 sodium D-gluconate, 250 mg·L^-1 Na₂MoO₄, 500 mg·L^-1 thiourea) into the simulated concrete pore solution containing 3.5% (w) NaCl, the inhibition efficiency of the compound inhibitor was 94.5%. According to the Hard and soft acids and bases (HSAB) theory, the compound inhibitor worked by forming a protective film on the steel surface.

A Mg-Al layered double hydroxide (LDH) was prepared from Mg(NO₃)₂·6H₂O and Al((NO₃)₃· 9H₂O by a constant-pH co-precipitation method at room temperature. PdCl2₄^- was successfully introduced into the gallery space of the Mg-Al-LDH via an ion exchange process, and then reduced by hydrazine to produce LDH-supported palladium (LDH-Pd⁰) nanomaterials. The sample was characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), and X-ray photoelectron spectroscopy (XPS). It was found that palladium nanoparticles were well dispersed on the LDH surface. The LDH-Pd⁰ nanomaterial was immobilized on a glassy carbon electrode (GCE) to oxidize hydrazine in a phosphate buffer solution (PBS, pH 7.0) using cyclic voltammetry (CV). The modified electrode exhibited excellent electrocatalytic activity and thus could be used to determine the concentration of hydrazine. This was verified by examining the amperometric response at a working potential of -0.1 V, where it was found that the anodic peak current of the modified electrodes was linear with hydrazine concentration in the range of 1.0×10^-5-2.0×10^-4 mol·L^-1. The detection limit was 9.5×10^-7 mol·L^-1 at a signal-to-noise ratio of 3. The electrochemically effective surface areas were determined by chrono-coulometry (CC) to be 0.02089, 0.02762, and 0.02496 cm² for GCE, LDH-Pd⁰/GCE, and LDH/GCE, respectively. The irreversible oxidation of hydrazine on the modified electrode is diffusion controlled with the participation of four electrons and four protons.

The effect of doping M (M = Mn,Y) into ceria-zirconia solid solutions on the activity of MnO_x/Ce_0.50-zZr_0.50-zM_2zO_y/Al₂O₃ for catalytic combustion of ethyl acetate has been investigated. It is found that doping of Mn increases greatly the oxygen storage capacity (OSC) of the oxygen-storage materials (OSMs); doping of Y decreases obviously the reduction temperature of catalysts; the doping of Mn and Y combines the advantages of doping of Mn and Y. MnO_x/Ce_0.40Zr_0.40Mn_0.10Y_0.10O_y/ Al₂O₃ has the best catalytic performance. The complete conversion temperature of ethyl acetate over the catalyst is 513K and the temperature range between T_10% and T_100% is the smallest. This catalyst can be applied to abatement of ethyl acetate under conditions of wider range of inert concentration and higher gas hourly space velocity (GHSV). Results of H₂-temperature-programmed reduction(H₂-TPR)and X-ray diffraction (XRD) analyses show that MnO_x/Ce_0.40Zr_0.40Mn_0.10Y_0.10O_y/Al₂O₃ has lower reduction temperature and larger peak area. Mn and Y enter the lattice of ceria-zirconia solid solutions, which improves the textural properties and greatly promotes the MnO_x dispersion on the support surface.

Combining co-precipitation-gelation, mechanical mixing and impregnation methods, a series of catalysts of FeK-M/γ-Al₂O₃(M=Cd or Cu) have been attained. The catalysts were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), N₂ physisorption, X-ray diffraction (XRD) and temperature-programmed reduction of hydrogen (H₂-TPR). The hydrogenation of carbon dioxide over these catalysts was also investigated in a fixed bed. Given a reaction time of 100 h, CO₂ conversion over a 15%Fe/10%K/γ-Al₂O₃ catalyst reached 51.3 %, with a selectivity towards C₂₊ of 62.6 % at 3 MPa, 673 K, a space velocity of 3600 h-1 and at a molar ratio of H₂/CO₂ of 3. At the lower Fe content of 2.5%, the selectivity towards C₂₊ was still greater than 60.0%. Increasing the potassium content from 0% to 10%, increased the selectivity towards C₂-C₄⁼ and the molar ratio of C₂-C₄⁼ /C₂-C₄⁰ increased to 3.6. The addition of Cd and Cu improved the reduction and catalytic activities. Specifically, Cu improved the molar ratio of C₂-C₄⁼ /C₂-C₄⁰ from 3.6 to 5.4, and the Cd increased the selectivity of C₅₊ by 12%.

Nickel multiwalled carbon nanotubes (Ni/MWCNT) and lanthanum-promoted Ni/MWCNT were successfully synthesized by impregnation. Methanation of carbon dioxide was used as a probe to evaluate their catalytic performance. N₂-BET, temperature programmed reduction (TPR), X-ray powder diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) were used to study the advantageous effects of La on the structure, surface composition, reduction properties and reaction performance of Ni/MWCNT. It was found that La-promoted Ni/MWCNT catalysts showed better catalytic activity for the reaction than the un-promoted. The addition of La to Ni/MWCNT improves the concentration and dispersion of the active NiO component on the catalyst surface, thus weakening the interaction between support and NiO species, which in turn improves the electron density at the NiO species. As a consequence, the adsorption of reactants was enhanced and the activity improved. Moreover, the sequence in which La was added was also studied in this work. Ni-La/MWCNT, in which La was impregnated onto the MWCNT first, shows better catalytic performance than La-Ni/MWCNT, where the Ni was impregnated first.

A series of core-shell bifunctional catalysts [CuO-ZnO-Al₂O₃]/[HZSM-5] for one-step synthesis of dimethyl ether from CO₂ hydrogenation were prepared by a hydrothermal synthesis method, and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). The catalyst has a core-shell structure with an integral and compact shell of HZSM-5 coated on the surface of a pre-shaped CuO-ZnO-Al₂O₃ pellet. The crystallite size and thickness of the zeolite shell can be controlled by the crystallization time. Compared with the mechanically mixed catalyst, the core-shell catalyst shows much higher selectivity for dimethyl ether synthesis from CO₂ + H₂. The core-shell catalyst with a crystallization time of 3 d shows the best catalytic performance, with a CO₂ conversion of 38.9% and a dimethyl ether selectivity of 77.0%.

Copper-iron modified bimodal support (M) with different mass fractions of Cu and Fe elements were prepared by an ultrasonic impregnation method. The catalytic performance for higher alcohol syntheses (HAS) was investigated in a fixed-bed flow reactor. Several techniques, including N₂ physical adsorption, temperature-programmed reduction/desorption of hydrogen, (H₂-TPR/TPD) and X-ray diffraction (XRD) were used to characterize the catalysts. The results indicated that the bimodal pore support was formed by the addition of small-pore silica sol into the macroporous silica gel. Increased amounts of small pore silica sol caused a decrease in pore size in the bimodal carrier. An increase in the Fe/Cu molar ratio facilitated the dispersion of CuO, promoted the reduction of CuO and Fe₂O₃ on the surface layers, and enhanced the interaction between the copper and iron species as well as the bimodal support inside the large pores. The copper was well-dispersed on the catalyst and the amount of iron carbides formed was high in catalysts with a high Fe/Cu molar ratio. Increasing the Fe/Cu mass ratio promoted the catalytic activity and thus facilitated the synthesis of higher alcohols. When the Fe/Cu molar ratio was increased to 30/20, the CO conversion and the yield of higher alcohols increased to 46% and 0.21 g·mL^-1·h^-1, respectively. At the same time, the mass ratio of C₂₊OH/CH₃OH reached 1.96.

One dimensional titanate nanotubes modified with copper nanospheres were synthesized through a facile one-step hydrothermal process. Transmission electron microscope (TEM), X-ray diffraction (XRD), and energy dispersive spectrometry (EDS) were used to monitor the changes in the morphology and phases during the hydrothermal process. The diameter of the Cu-TiO₂ composite nanotubes was 10-15 nm and their lengths were ca 100 nm, the dimension of the covered Cu nanoparticles was about 5 nm. Brunauer-Emmett-Teller (BET) tests revealed the specific surface area of the Cu-TiO₂ composite nanotubes to be 154.67 m²·g^-1. The formation process and mechanism of the composite nanotubes were surveyed by adjusting the hydrothermal duration and titanium precursor. The results revealed that an amorphous titanium precursor is essential for the successful formation of this unique topography and phase composition. Anti-Ostwald ripening, a decrease in the dimensions of the copper nanospheres with hydrothermal time, was observed in the TEM images, which is of benefit to helps keep the particles on the nanoscale. The UV-Vis spectrum of the as-prepared material exhibits a strong absorption at 350-800 nm in the visible band compared with commercial TiO₂ nanopowders. The plasmonic absorption of metallic copper particles between 550 and 600 nm is seen in the UV-Vis spectrum. Schottky barriers between copper-TiO₂ interfaces make this kind of material a potential agent in speeding up electron transport rates and slowing recombination rates. Photocatalytic experiments demonstrated this unique Cu-TiO₂ composite nanotube material has a high photocatalytic activity under visible-light irradiation.

Lanthanum-doped bismuth titanate (Bi_3.25La_0.75Ti₃O₁₂, BLT) nanowires were synthesized by a one-step hydrothermal process and their optical and photocatalytic properties were investigated. Their crystal structure and microstructures were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), and high-resolution transmission electron microscopy (HRTEM). The BLT nanowires obtained are single-phase with an average diameter of 25 nm. The room temperature photoluminescence (PL) spectrum reveals two visible emission peaks at 400 and 596 nm, which are assigned to excitonic and surface-defect emissions, respectively. The UV-visible diffuse reflectance spectrum (UV-Vis DRS) reveals that the band gap of BLT nanowires is 2.07 eV. The prepared BLT nanowires are stable and exhibit higher photocatalytic activities in the degradation of methyl orange (MO) under visible light irradiation (λ >420 nm) compared with commercial P25 TiO₂, traditional N-doped TiO₂ (N-TiO₂), and pure bismuth titanate (Bi₄Ti₃O₁₂, BIT). The high photocatalytic performance of BLT photocatalysts is attributed to the strong visible light absorption and the recombination restraint of the e^-/h⁺ pairs resulting from the presence of La³⁺ ions.

BiOI-sensitized nano-anatase (TiO₂ (A)) photocatalysts were prepared by a deposition method at room temperature, and characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and photoluminescence (PL), and UV-Vis diffuse reflectance spectra (UV-Vis DRS). The photocatalytic activities were evaluated by photo-degradation experiments of rhodamine B. With increasing BiOI content, the absorption intensity of BiOI/TiO₂ (A) increases in the 370-630 nm region and the absorption band edge redshifts. The UV and visible light photocatalytic activities increase, reaching a maximum when the Bi/Ti molar ratio is 1.7% . The 1.7% BiOI/TiO₂ (A) catalyst exhibits much higher visible-light photoactivity than P25, and its UV-light photoactivity is slightly higher than that of P25. The UV and visible light photocatalytic activities of BiOI/TiO₂ (A) with similar BiOI content are lower than those of BiOI/P25 catalysts. Compared with TiO₂ (A), 1.7% BiOI/TiO₂ (A) shows higher UV and visible light photoactivities. This is attributed to the strong absorption in the 370-630 nm region, the redshift of the absorption band edge, and the effective transfer of the photogenerated electrons and holes, which reduces the recombination of electron-hole pairs.

Two novel bis(1,8-naphthalimides) (3 and 5) containing triazine spacers have been synthesized from 1,8-naphthalic anhydride and cyanuric chloride. The photophysical properties of 3 and 5 have been investigated by UV-Vis absorption and fluorescence spectroscopy. As with N-butyl-1, 8-naphthalimide in polar dichloromethane, chloroform or methanol, the fluorescence spectra of 3 and 5 exhibit a short-wavelength emission band (λ<400 nm) typically observed for 1,8-naphthalimide derivatives, and a broad and red-shifted intramolecular excimer emission band (λ>450 nm). In addition, owing to the specific conformational isomerism, the emission intensity of 3 is significantly quenched by intramolecular electron transfer. In the apolar solvent methyl cyclohexane, the strong hydrogen-bonding interactions between triazine linkers drive monomeric 5 aggregation that is responsible for intermolecular excimer emission. In toluene, both 3 and 5 do not display strong excimer emission. Instead, exciplex formation of toluene with naphthalimide moieties in 3 or 5 is observed. Finally, the excited-state properties of solid films of 3 and 5 have excimer emission around 465 and 469 nm, respectively.

Three star-burst conjugated oli mers based on triphenylamine (TPA), fluorene and spiro (fluorene-9,9'-xanthene) (SFX) have been synthesized via the Sonogashira cross-coupling reaction. These well-defined oli mers possess high decomposition temperatures (T_d) at 417, 439, and 425 °C, respectively. Differential scanning calorimetry (DSC) demonstrates two oli mers which incorporate the SFX unit, TPA-SFX and TPA-SFXCz, possess higher glass transition temperatures (T_g) at 141 and 127 ° C, respectively, compared with 101 °C for TPA-F. The investigation of their optical properties shows TPA-SFX and TPA-SFXCz exhibit a single blue emission in film with emission peaks at 434 and 442 nm, respectively, whereas TPA-F shows a broad double-peak emission located at 424 and 455 nm, which implies the nonplanar TPA and spiro SFX moieties can effectively restrict the formation of aggregates or excimers. Electrochemical investigations show that these oli mers have relatively high HOMO levels at around -5.4 eV due to incorporation of the electron-rich TPA core. Electroluminescence (EL) devices with a configuration of ITO (indium tin oxide)/PEDOT:PSS (poly(3,4-ethylenedioxythiophene): poly (styrenesulfonate))/ oli mer/TPBI (1,3,5-tris(1-phenyl-1H -benzimidazol-2-yl)benzene)/LiF/Al were constructed using these oli mers as the emitter by spin-coating, with TPBI as the electron-transporting and hole-blocking layer. The device using TPA-SFX as the emitting layer exhibits bright blue emission with the maximum brightness and maximum current efficiency of 2680 cd·A^-2 and 0.35 cd·A^-1, and CIE color coordination of (0.17, 0.13).

The properties of the liquid ordered (L_o) phase of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC)/stigmasterol liposomes were investigated using synchrotron small-angle and wide-angle X-ray diffraction techniques. The lamellar repeat distance of the L_o phase, derived from small-angle X-ray scattering experiments, changes slightly with sterol concentration and temperature. While the d-spacings of the acyl chains, evaluated from wide-angle X-ray scattering data, show a much broader range than those of the gel and liquid-crystal phases, varying from 0.422 to 0.460 nm when the temperature increases from 30 to 52 °C. The electron density profiles show that the bilayer thickness and the water-layer thickness of the liquid-ordered phase are larger than that of the liquid-crystal phase, and the bilayer thickness of the liquid-ordered phase decreases with increasing temperature. The results of this study are of help in understanding the phase state and the ordered structure of biomembranes.