The microscopic local environmental structure of Cu2+ ions in copper chloride solutions was investigated by X-ray absorption fine structure (EXAFS) spectroscopy. The effects of salt concentration and freeze-thaw (FT) treatment on the first coordination shell of Cu2+ were analyzed by examining the Cu K edge EXAFS spectra of CuCl2 aqueous solutions before and after FT treatment at various concentrations. The EXAFS results show that Cu2+ has 3.0-4.3 oxygen nearest neighbors with Cu—O bond length of 0.192 -0.198 nm in the first coordination shell. These structural properties can be ascribed to the Jahn-Teller effect. We found differences in the microscopic local structure of Cu2+ for various concentrations in CuCl2 aqueous solutions.With an increase in the salt concentration, the coordination number of Cu2+ decreases and the Cu—O bond length increases in the first coordination shell. The influence of FT treatment on the microscopic local environmental structure of Cu2+ was determined fromthe fitting results of the structural parameters. The coordination number of Cu2+ in its first coordination shell and the degree of thermal disorder increase when the FT treatment is operated in CuCl2 aqueous solutions.

Clean air at high temperature and velocity is used as the oxidant during fuel combustion in a hypersonic scramjet. In ground tests, however, the high-temperature air produced by combustion heating contains H2O and CO2 as contaminants. In this study, the influence of H2O and CO2 in air upon the equilibrium temperature and pressure, and the ignition delay time for ethylene combustion were investigated by a kinetics simulation method using a plug flow reactor. Different initial temperatures, pressures, and equivalence ratios were studied. We find that the presence of H2O promotes combustion whereas CO2 inhibits combustion. Both H2O and CO2 result in a decrease of the equilibrium temperature and pressure during ethylene combustion, and CO2 has a comparatively larger influence than H2O. The simulated result was used to interpret the experimental phenomena.

The electroreduction of cinnamonitrile in MeCN solution was studied using cyclic voltammetry, with two reduction peaks at -1.46 and -2.0 V. Linear, cyclic hydrodimers, and 3-phenyl pentanedinitrile were synthesized at the first peak, while additional saturated hydro product was synthesized at the second peak. The reduction mechanism was proposed based on the experimental and cyclic voltammogram simulation results. Linear and cyclic hydrodimers were synthesized by a radical-radical (RR) route while a saturated hydro product was obtained via an electrochemical-electrochemical-chemical-chemical (EECC) process. 3-Phenyl pentanedinitrile was synthesized by the reaction of cinnamonitrile with the conjugate base of MeCN. Finally, the dynamic constants were calculated using cyclic voltammogramsimulation. Result indicated that the rate constant of the RRreaction was found to be 104 L·mol-1·s-1, and the rate constant of the second electron transfer reaction was 0.3 cm·s -1, while the rate constant of the subsequent proton reaction was 105 s-1.

Ball milling in combination with heat treatment was used to prepare sulfur-based composite cathode materials incorporating multi-walled carbon nanotubes (MCNTs) for Li-S battery. The structure and morphology of the as-prepared cathode materials were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The effect of MCNT content and binder type on the capacity, cyclability and self-discharge behavior of a sulfur-based cathode were systematically investigated. Results show that the appropriate amount of MCNTs is 5%-8% (w, mass fraction) and the use of β-cyclodextrin as a water-soluble binder to fabricate the cathode results in the best electrochemical performance. When the Li-S battery was half charged at room temperature, there was almost no self-discharge during storage for 30 d. The charging capacity was 687.7 mAh·g-1 during the 1st cycle and 623.8 mAh·g-1 during the 100th cycle for the cathode at a current rate of 0.1C. Therefore, 90.7%of the capacity was retained.

Electroactive composite films of carbon nanotubes/polyaniline/nickel hexacyanoferrate (CNTs/PANI/NiHCF) were synthesized on platinum substrates modified with CNTs by a one-step co-polymerization using cyclic voltammetry. The composite films were characterized by Fourier transforminfrared spectroscopy (FT-IR), energy dispersive X-ray spectroscopy (EDS), and scanning electron microscopy (SEM). Cyclic voltammetry (CV), galvanostatic charge/discharge, and electrochemical impedance spectroscope (EIS) methods were used to study the cycling stability and the electrochemical capacitive performance of the CNTs/PANI/NiHCF films. Results showed that three-dimensional porous network composite films with uniform distributions of PANI and NiHCF nanoparticles on the CNTs were formed by this new method. The specific capacitance of the inorganic-organic hybrid films were 262.28 F·g-1 with a specific energy of 29.51 Wh·kg-1 at a current density of 2 mA·cm-2. The specific power was 10228.61 W·kg-1 at a current density of 10 mA·cm-2. Meanwhile, CNTs/PANI/NiHCF films showed a capacity decay of only 19.92% after 2000 charge/discharge cycles and had a coulombic efficiency of over 99%. Therefore, the composite films exhibit outstanding power performance, fast dynamics of charge transport and are excellent materials for use in supercapacitors.

N-doped TiO2 films were prepared on indium tin oxide(ITO) conducting glass by dc-reactive magnetron sputtering using a Ti target in an O2/N2/Ar mixture gas in combination with heat-treatment at 300-500 ℃. The microstructure, optical and photoelectrochemical properties of the as-formed filmswere characterized byX-ray diffraction (XRD), X-ray photoelectron spectroscopy(XPS), scanning electron microscopy(SEM) and UV-Vis transmittance spectrum. Highly porous NiO was deposited onto the N-doped TiO2 layer by chemical bath deposition to obtain ITO/TiO2-xNx/NiO bilayer thin films and they exhibited excellent and noticeable photoelectrochromism. The TiO2-xNx film annealed at 400 ℃ showed the highest photocurrent response. The color of films changed from colorless to brown and the transmittance varied from 79.0% to 12.6% at 500 nmafter 1 h of irradiation.

To investigate the hydration of proteins in magnetized water, pure water was treated with a static magnetic field (MF) over different effective treatment time (teff). Viscosimetry and oxygen nuclear magnetic resonance (17O-NMR) spectra were recorded. The hydration properties of β-lactoglobulin (β-Lg) in magnetized water were examined by differential scanning calorimetry (DSC) and NMR. By increasing teff, the internal energy of the water decreased and the concentration of“hydrogen-bonded”water increased. This result indicates that MF treatment promotes the formation of water clusters, which can be attributed to an increase in hydrogen bonding. For the β-Lg solution prepared in magnetized water, the mobility of water molecules around the β-Lg surface did not change significantly with an increase in teff but the quantity of non-freezable bound water increased. This suggests that β-Lg hydration is related to the formation of water clusters, which depends on the hydrogen-bonding structure of water and can be varied by MF treatment.

The structures and properties of lecithin/amino acid/H2O micelle and liposome systems were studied using electrical capacitance. The critical micellar concentration and the liposome formation concentration of lecithin can be obtained from the relation of system capacitance with lecithin's concentration. With an increase in lecithin concentration, the capacitance increases and lecithin aggregates from the micelles to liposomes. With the increase of amino acids, the radii of the micelles and liposomes increase but the capacitance decreases. Amino acids can promote micelle and liposome formation as well as decrease the critical micellar concentration and the formation concentration. The sequence of amino acid influence on the capacitance is as follows: histidine>tryptophan>>glycine.

We investigated the micelles, reverse micelles, and microemulsions formed by three kinds of tetradecyl aryl sulfonates synthesized in our laboratory under different conditions using surface tension, iodine spectrometry, water solubilization, and phase diagram methods. The influences of molecular structure, solvents, inorganic saltss and short chain alcohols on these molecular organized assemblies were discussed. Results show that aqueous solutions or mixed polar solvents (EG-water) are unfavorable for micelle formation but that reverse micelle formation in non-polar solvents (n-heptane) is favorable when the branching coefficients of the lipophilic group in the tetradecyl aryl sulfonate molecules increase. A decrease in solvent polarity causes the surfactant solution to transform from a micellar solution to a monomer solution and then to a reverse micellar solution. Upon addition of inorganic salts or short chain alcohols, micelle formation is favored in aqueous solutions. Together with higher counter-ion valence states or alcohol alkyl carbon atoms, micelle formation increases even further. As the concentration of inorganic salt increases, the surfactant/n-butanol/n-octane/NaCl/ water microemulsion systems transform from Winsor I to Winsor III and then to Winsor II at specific temperatures.

A series of amphiphilic polymers were synthesized by the statistical polymerization of 2-(acrylamido)-dodecanesulfonic acid (AMC12S) with 2-(acrylamido)-2-methylpropanesulfonic acid (AMPS) and they contained a high mole fraction of AMC12S (X=0.1, 0.3, 0.5). The aggregation behaviors of the polymers and their interactions with three nonionic surfactants HO(CH2CH2O)10C12H25 (C12E10), HO(CH2CH2O)20C12H25 (C12E20), and HO(CH2CH2O)40C12H25 (C12E40) in aqueous solutions were investigated by steady-state fluorescence and quasi-elastic light scattering measurements. The effect of X on the association performance and the influence of the surfactant's hydrophilic group length on these interactionswere also investigated. The critical aggregationconcentration(CAC) of the polymerwas found to significantly decrease with increasing X. The CAC of the polymer with X=0.5 is as low as 0.0039 g·L-1. The hydrodynamic sizes of the aggregates (Rh) are larger than 26 nm and increase with an increase in polymer concentration, indicating that the polymeric molecules exhibit a strong tendency for interpolymer association, leading to the formation of multimolecular aggregates. When X increases, both Rh and its tendency to increase decrease, suggesting that the aggregates become more compact. The interaction between surfactant and polymer is very strong and the polymer aggregates begin to collapse when the surfactant concentration reaches the critical micelle concentration (CMC) in the mixed solutions and mixed aggregates form. The destructive ability of the surfactant increases as the length of the hydrophilic group increases. The Rh value of the mixed aggregates formed by C12E40 and the polymer with X=0.5 is 6.8 nm, which is consistent with the Rh value of the C12E40 aggregates.

A series of Ce1-xFexO2 mixed oxides with different Ce/Fe molar ratios were prepared via hydrothermal method. The effect of Fe content on structure and porperty of the prepared catalysts were characterized by powder X-ray diffraction (XRD), BETspecific surface area, Raman spectroscopy, and H2 temperature-programmed reduction (H2-TPR) techniques. The performance of the catalysts for soot oxidation was evaluated by temperature-programmed oxidation (TPO). Results showed that Fe3+ did not readily dissolve into the ceria lattice and some Fe2O3 highly dispersed on the surface of ceria. Both the formation of Ce-Fe solid solution created sites (oxygen vacancies) for absorbing and activating oxygen, and the presence of surface Fe2O3 strongly improved the aging resistance of the catalysts. With well dispersed surface Fe2O3 and the largest dopant content, the Ce0.8Fe0.2O2 catalyst had the lowest Ti (262 ℃, ignition temperature of soot oxidation) and Tp (314 ℃, temperature of maximumevolution of CO2). Even after aging for long periods at high temperature, the Ti and Tp values for Ce0.8Fe0.2O2 were still relatively low, at 292 and 392 ℃, respectively, indicating high thermal stability.

A series of modified nanosized HZSM-5 zeolites were prepared by hydrothermal treatment at different temperatures and characterized by the adsorption and desorption of N2, X-ray diffraction (XRD), Al solid state magic angle spinning nuclear magnetic resonance (27Al MAS NMR), temperature-programmed desorption of ammonia (NH3-TPD), and Fourier transforminfrared (FT-IR) spectroscopy of adsorbed pyridine techniques. The conversion of methanol to propene was tested using a continuous flow fixed-bed microreactor at atmospheric pressure, 500 ℃, and a methanol weight hourly space velocity (WHSV) of 1.0 h-1. Results showed that after the appropriate hydrothermal treatment, some of Al was removed from the framework of zeolite and extracted out of the zeolite channels after treatment with an aqueous solution of citric acid. This led to a decrease in the strength and amount of acidic sites and an increase in the volume and diameter of the pores. As a result, propene selectivity and the reaction time continued to maintain the total conversion of methanol (i.e., life time of catalyst) increased significantly to 38.9%and 160 h from 30.1%and 75 h over the parent nanosized HZSM-5 zeolite. However, severe hydrothermal treatment decreased the acidity remarkably and the strongly acidic sites were almost totally destroyed, resulting in a remarkable decrease both in propene selectivity and catalyst stability.

Novel Cu-Co/SiO2 catalysts were prepared by conventional impregnation methods with the assistance of glow discharge plasma technology. Compared with a conventional calcined sample, the plasma remarkably improved the specific surface area of the catalyst and increased the concentration of active cobalt species on the catalyst's surface. The reducibility of the cobalt was effectively improved as well. Catalytic test results showed that comparison to the conventional 673 K calcined sample, the CO hydrogenation activity of the two plasma enhanced samples (one treated only by plasma and the other assisted by plasma followed by calcination) increased by 30.46% and 65.30%, respectively. Their time space yields of higher alcohols also increased by 58.22% and 76.11%, respectively, under 5.0 MPa, 6000 h-1, 563 K and a H2 /CO volume ratio of 1.6.

A thermodynamic analysis of the partial oxidation of methane (POM) in coke oven gas (COG) was carried out. The optimized conditions were CH4/O2 molar ratios of 1.7-2.1 and reaction temperatures of 825-900 ℃. We obtained CH4 conversions of 91.0%-99.9%, H2 selectivity of 87.0%-93.4%, and CO selectivity of 100%-107% at 1.01×105 Pa. The effect of H2 in the COG on the performance of POM was also investigated between 825 and 900 ℃. The optimized volume ratio of steam addition was 2%-4% and the molar ratio of CH4/O2 was 2 at 1.01×105 Pa and 825-900 ℃. A maximum conversion rate of 98.6%was achieved for CH4 using COG, while the maximum selectivities of H2 and CO were 96.4% and 107%, respectively. The amount of hydrogen obtained after reforming was doubled despite a thermal consumption of only 2.94 J·mol -1 for the COG. The performance of a NiO/M solid solution catalyst packed on a BaCo0.7Fe0.2Nb0.1O3-啄(BCFNO) membrane reactor was also investigated for the POMin COG. The reforming process was successfully performed. At 875 ℃, 95% CH4 conversion, 80.5% H2 selectivity, and 106% CO selectivity at an oxygen permeation flux of 16.3 mL·cm-2·min -1 were achieved. The results for POM reforming in COG on the membrane reactor were consistent with the thermodynamic analysis. The NiO/M solid solution catalyst, therefore, has od activity and is suitable for application in hydrogen production.

The crosslinking copolymerization of 2-hydroxyethyl methacrylate (HEMA) and N-vinylpyrrolidone (NVP) was performed using the inverse suspension polymerization method resulting in crosslinked HEMA/NVP microspheres. Subsequently, the graft polymerization of methacrylic acid (MAA) was conducted using the“grafting from”method and the grafted PMAA-HEMA/NVP microspheres were obtained. The adsorption property and adsorption mechanism of the grafted microspheres were investigated in depth using lysozyme (LYZ) as a basic protein model. The zeta potential of the grafted microspheres was determined. Several factors that affected the adsorption property of the system such as the pH of the medium, the grafting degree of the microspheres and the ionic strength were examined. Experimental results indicate that in a wide pH range, the zeta potential of the grafted PMAA-HEMA/NVP microspheres has a large negative value. Therefore, a high density of negative charge is present on the surfaces of the grafted microspheres. The strong electrostatic interaction results in which the grafted PMAA-HEMA/NVP microspheres exhibit very strong adsorption ability toward lysozyme. The adsorption capacity of the grafted microspheres for lysozyme initially increases and then decreases as the pH increases and a maximumadsorption (90 mg·g-1) is found at pH=9, which is close to the isoelectric point of lysozyme. The ionic strength affects the adsorption property of the grafted microspheres greatly. As pH<9, the adsorption capacity of lysozyme decreases as the NaCl concentration increases, whereas as pH>9, the adsorption capacity of lysozyme increases as the NaCl concentration increases.

We studied the isothermal adsorption of naphthalene on a viscose-based activated carbon fiber (VACF) in aqueous solution. The adsorption experimental data were fitted to adsorption equations such as the Langmuir, Freundlich, Dubinin-Radushkevitch(D-R), Dubinin-Astalov(D-A), Langmuir-Freundlich(L-F), and Redlich-Peterson (R-P) equations. The effects of temperature, pH, and pre-loaded copper ions on the VACF on the adsorption of naphthalene were investigated. The fitting results show that the micropore volume filling theory fits better than the single-layer adsorption theory for naphthalene adsorption onto VACF. The adsorption of naphthalene occurs spontaneously between 20 and 40 ℃. The adsorption capacity of VACF for naphthalene decreases significantly above 30 ℃. A new mechanism is proposed to explain why the adsorption capacity increases significantly in lower pH aqueous solutions. The reduction of naphthalene takes place on the VACF with pre-loaded copper ions.

Copper (II) oxide nanoparticles were incorporated into the pore systemof mesoporous carbon CMK-3 by a facile method, forming the composite Cu/CMK-3. Cu/CMK-3 was characterized by powder X-ray diffraction, nitrogen physisorption, and transmission electron microscopy. Results showed that Cu/CMK-3 preserved the ordered mesoporous structure of CMK-3 and copper (II) oxide was dispersed within the CMK-3 channels as small nanoparticles. CMK-3 still had a large surface area after copper (II) oxide was incorporated. The adsorption and catalytic dry oxidation ability of Cu/CMK-3 for phenol was determined. The adsorption and recycle results indicate that Cu/CMK-3 adsorbs aqueous phenol well because of its large surface area. Most of the phenol adsorbed on CMK-3 was catalytically dry-oxidized at relatively low temperature. We demonstrate that Cu/CMK-3 can be used as a sorbent-catalyst for aqueous phenol. After seven cycles, Cu/CMK-3 retained a substantial fraction of its adsorption ability for phenol. A combined thermogravimetry-mass spectroscopy (TG-MS) instrument was used to investigate the catalytic activity and ignition behavior of Cu/CMK-3. Results show that CuO is the active component during the catalytic dry oxidization of phenol. The adsorbed phenol is catalytically dry-oxidized into carbon dioxide and water at the relatively low temperature of about 180 ℃, where no phenol desorption or CMK-3 ignition occurred.

Zeolite MeLTL with a micro-mesoporous composite pore structure was synthesized by using nanocrystal clusters of zeolite L prepared by the crystallization nurturing method as a precursor and [3-(trimethoxysilyl)propyl] hexadecyldimethylammonium chloride (TPHAC) as the organic mesopore directing surfactant. Several techniques including X-ray diffraction (XRD), nitrogen adsorption-desorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM), 27Al magic angle spinning nuclear magnetic resonance (27Al MAS NMR), and Fourier transform infrared spectroscopy of pyridine adsorption (Py-FTIR) were used to characterize the samples. Results show that zeolite MeLTL is formed by the self-assembly of zeolite L nanocrystals, and it has bimodal pore distributions with a stepwise mesoporous structure and the microporous structure of zeolite L. The BET surface area and the pore volume increased significantly and were 611 m2·g-1 and 0.696 cm3·g-1, respectively. Zeolite MeLTL was composed of zeolite L units and this was responsible for the adequate surface acid amount and acid strength. As a result, the pore diffusion ability and the catalytic performance of zeolite MeLTL are enhanced by the improvement in textural properties. For diesel hydrodesulfurization, the catalyst introduced zeolite MeLTL gave better hydrodesulfurization activity compared to the catalysts introduced zeolite L or Al-MCM-41 or used bare γ-Al2O3 as a support. The sulfur content of diesel oil after hydrotreatment was 9.3 μg·g-1 and the desulfurization rate was 99.3%.

The Pt-loading properties of ordered mesoporous carbon (OMC) synthesized with assistance of MClx (M=Pd, Fe, Cr; x=2, 3, 3) were investigated. X-ray diffraction (XRD) and transmission electron microscope (TEM) show that the ordered structure is well-preserved after the introduction of PdCl2. Because of the pyrolysis of organic carbon the OMC-PdCl2 is mainly present in the formof metallic Pd and is homogenously embedded into the scaffold of the OMC. A binary catalyst comprised of metallic Pd and microwave-reduced Pt nanoparticles was also generated. Electrochemical hydrogen absorption-desorption tests reveal that Pt/OMC-MClx possesses excellent catalytic performance and has an electrochemical active surface area (SEA) being as 2-4 times as that of Pt/OMC. Pt/OMC-PdCl2 has the highest SEA of 120.2 m2·g-1 followed by Pt/OMC-CrCl3 and then Pt/OMC-FeCl3. After a long-term cyclic voltammetric test, Pt/OMC-MClx still exhibits excellent catalytic stability and relatively higher catalytic activity as evidenced by a 22%-40% decrease in catalytic activity after one hundred cycles. This work will open up a most promising application in catalysis.

Highly efficient red organic light emitting diodes with a p-type structure were fabricated. The luminance, current density, and efficiency were improved compared to those of the control device. We obtained the p-type structure by doping the strong electron-withdrawing material 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquino-dimethane (F4-TCNQ) into the hole-injection layer of 4,4',4''-tris(3-methyl-phenylphenylamino)-tri-phenylamine (m-MTDATA). This p-type structure was further applied to white organic light emitting diodes (WOLEDs). The white emission of the WOLEDs consists of red, green, and blue components emitted fromthe Ir(DBQ)2(acac), Ir(ppy)2(acac), and FIrpic doped 1,3-bis(carbazol-9-yl)benzene (mCP) layers, respectively. The emission intensity of the different colors can be adjusted by changing the doping concentrations and the thickness of the corresponding layer. After optimizing the emission intensity of every emitting layer, the maximum current efficiency, power efficiency, and luminance of the device were found to be 19.3 cd·A-1, 12.1 lm·W-1, and 31770 cd·m-2, respectively. The Commission Internationale De L'Eclairage (CIE) coordinates of the device were stable and remained in the white region when the driving voltage increased from 5 to 11 V.

Co-adsorption with molecules that strongly adsorb on metallic surfaces is beneficial in improving the surface-enhanced Raman spectroscopy (SERS) detection sensitivity of some weakly adsorbed molecules or ions. In this paper, the co-adsorption of four deoxyribonucleic acid (DNA) bases: adenine, guanine, cytosine, and thymine with ClO-4 was studied. Factors like adsorption ability, applied potentials, and coexisting anions were examined to illustrate how they affect co-adsorption. We found that the four DNA bases in their protonated forms could co-adsorb with ClO-4. Among them, thymine with the weakest adsorption ability on Au showed the weakest co-adsorption ability with ClO-4. In addition, repulsion from both negative potentials and reduced SERS enhancements of Au substrates at relatively positive potentials led to a decrease in the SERS intensity of ClO-4. Moreover, anions such as Cl-, NO-3 , and SO2-4 were shown to influence the co-adsorption of ClO-4 with adenine based on a dynamic and reversible competitive co-adsorption process. The above results are very helpful in optimizing the SERS detection sensitivity of weakly adsorbed ions or molecules via the co-adsorption method.

Transient photovoltaic and surface photoacoustic techniques were used to investigate the separation and recombination processes of photogenerated charge carriers and the mechanism of energy conversion for mesoporous La-doped nano-TiO2. Results indicate that two defect states with different photovoltage characteristics have a short diffusion distance and a fast recombination velocity for the electron hole pair; and that doped lanthanum increases the contribution of bulk defects to the photovoltaic effect, but inhibits the main bandgap charge separation to a certain extent. Additionally, we show that both the mechanism of separation and recombination of the main bandgap electron hole pair and the intensity of the lattice vibration resulting from the non-radioactive transition are highly dependent on the type of template. These experimental results confirm that an obvious energy balance relationship exists between transient photovoltaics and surface photoacoustic phenomena.

The structures of β-octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (β-HMX) and its complexes with the pyrolysis products (NO2, OH, OH-) of ammonium perchlorate (AP) were optimized at the B3LYP/6-31g(d) level of density functional theory (DFT). We obtained bond dissociation energies for N—NO2 in β-HMX and its complexes. We found that the geometrical configurations of HMX in the complexes with NO2 and OH were similar to the β-HMX structure but that the intrinsic symmetry decreases. The configurations of the OH- complexes are different and the original Ci symmetry is lost. Results further indicate that NO2 can easily capture a H from methylene on the HMX ring, which changes the initial pyrolysis channel of HMX. The influence of OH is negligible. The N—NO2 bond dissociation energies of OH- complexes decrease by about 200 kJ·mol-1 in comparison with that of β-HMX, which indicates that OH- can clearly promote the initial pyrolysis of β-HMX. The existence of NO2 and OH- can decrease the decomposition temperature of HMX greatly.

Density functional theory with the generalized gradient approximation was used to determine the geometries, energies, transition states, and vibrational frequencies of the [AlCl]n(n=1-10) clusters that form during the production of aluminum by the carbothermic reduction-disproportionation reaction. The ground state and trends observed during the formation of [AlCl]n were confirmed. Results indicate that the ground state geometric configurations of the [AlCl]n(n=1-10) clusters are frameworks of [Al]n bound to n Cl atoms and they have excellent geometric symmetry. Activation energies obtained from transition state calculations indicate that the activation energy of the reverse process is always higher than that of the forward process. This means that AlCl tends to form [AlCl]n. Our results can help in the understanding of this aluminumproduction mechanismduring the carbothermic reduction-disproportionation reaction.

The structural and dynamic properties of anionic surfactant at the water/n-alkane (nonane, decane, and undecane) interface were investigated by the molecular dynamics simulation. The model anionic surfactant contained a benzene sulfonate group attached to the 4th carbon in the hexadecane backbone and was denoted as 4-C16. We analyzed the interfacial properties (density profile, interfacial tension, and radial distribution function) of the n-alkane-surfactant-water systems in different oil phases and under special inorganic salinity conditions. The simulation results indicate that a well-defined interface exists between the n-alkane and water phases in the equilibrated model systems. The interfacial tensions of the n-alkane-surfactant-water systems show little change when sodium chloride is added to the solutions. We find that a change in the trans-form fraction of the dihedral in 4-C16 is related to a subtle change in the interfacial tension at the water/n-alkane interface. Clearly, the structure of the surfactant at the interface plays an important role in reducing the interfacial tension. In addition, we also find that the polar head group of the surfactant molecules with sodiumions and water molecules under stronger interactions.

Single-electron lithium bond complexes CH3…Li—CH3(I), H3CH2C…Li—CH3(II), (H3C)2HC…Li—CH3 (III), and (H3C)3C…Li—CH3(IV) were investigated at the B3LYP/6-311++G(d,p) and MP2/6-311++G(d,p) levels of density functional theory. Results showed that the single-electron lithium bond strength of the complexes H3CH2C…Li—CH3(II), (H3C)2HC…Li—CH3(III), and (H3C)3C…Li—CH3(IV) increased in the following order: II (-26.7 kJ·mol-1)<III(-30.2 kJ·mol-1)<IV(-32.8 kJ·mol-1). By comparison to the monomer Li—CH3, the vibrational frequencies of Li—CH3 in complexes II, III, and IV were abnormally blue-shifted by 15.1, 18.9, and 20.5 cm-1, respectively. The Li—CH3 bond was also elongated. The number of CH3 in electron donors was more, the single-electron interactions were stronger. As the H atom in the electron acceptor LiH was replaced with CH3, the interaction strength weakened. Additionally, we studied the characteristics of these complexes by nature bond orbital (NBO) and atom in molecules (AIM) methods.

Several ab initio methods were employed to investigate the structures and electronic properties of PdO0,±1, PdH0,±1, and PdOH. Two states (3∏and 3∑-) with similar energies were found for PdO. Energetically, the 3∏ state is more favored compared to the 3∑- state. At the coupled-cluster method with single and double excitations (CCSD) level of theory, the 3∑- state is 0.286 eV higher in total energy than the 3∏state. Based on the favored structures, we calculated the adiabatic ionization energies (AIE) and electronic affinities (AEA) of the PdO and PdH molecules. Our calculated values of AIE and AEA are in od agreement with the available experimental values. Geometry optimization result showed the ground state of PdOH to be a non-linear Pd—OH (2A') structure with Cs symmetry. In addition, we obtained two metastable structures Pd—OH (2A'') and O—Pd—H (2A''). We optimized the transition state connecting these two metastable states and calculated the corresponding energy barrier.

We investigated the spin-forbidden reaction mechanism of CO2 cleavage, activated by W+ in gas phase, using density functional theory (DFT, UB3LYP) with the relativistic effective core potential (ECP) of basis sets (SDD) for Wand the 6-311+G(3d) basis set forCand O. The calculation results showthatW+ initially closes to CO2 on the sextet surface, then the products, WO+ and CO, exit the channel on the quartet surface. The process involves an intersystem crossing (ISC) from the sextet to the quartet state. We obtained a minimum energy crossing point (MECP) using the al rithm in Harvey method. The large spin-orbital coupling (SOC) constant (494.95 cm-1) calculated shows that the spin-forbidden reaction takes place easily. Furthermore, the overall exothermicity is 122.33 kJ·mol-1.

The structures of eight kinds of rhodamine compounds, substituted by different alkyls at different positions, were optimized using the density functional theory (DFT) at the B3LYP level. On the basis of these optimized structures, the influence of the substituting group on the electronic structures and spectral properties as well as frontier molecular orbitals of rhodamine were analyzed using the singlet configuration interaction (CIS) method and time dependent density functional theory (TD-DFT). Results indicate that the frontier molecular orbitals are mainly distributed in the xanthene ring of rhodamine when only one H atom of the two N-ends in the rhodamine molecule is substituted by alkyls. The distribution of the highest occupied molecular orbital (HOMO) is the greatest in the main conjugate ring and the difference in the distribution ratio between the HOMO and the the lowest unoccupied molecular orbital LUMO) is small. When the four H atoms of the two N-ends in the rhodamine molecules are substituted by methyl, the bandgap is found to be the narrowest and the red shift in the gas maximum absorption wavelength is the largest. When the four H atoms of the two N-ends in rhodamine molecules are substituted by ethyl, the gas fluorescence maximum emission wavelength is the longest.

The geometric and electronic properties of AumPdn (m+n≤6) binary clusters were investigated at the UBP86/LANL2DZ and UB3LYP/def2-TZVP levels of theory. Structural features, binding energies, vertical ionization potentials, vertical electron affinities, charge transfer, and binding characteristics were determined for each Au-Pd binary cluster. For the five-and six-atom Au-Pd binary clusters, except for the mono-substituted mixed clusters (AunPd and AuPdn, n=5 or 6), the palladium atoms combined to form a Pdcore and the ld atoms were located around the Pdcore to produce the PdcoreAushell structure. The highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO), vertical ionization potentials (VIP), vertical electron affinities (VEA), Fermi levels, and chemical hardness of the AumPd and AumPd2 clusters are similar to those of the pure ld clusters, indicating an odd-even oscillation. The electronic properties of the mixed clusters, such as the HOMO, LUMO, VIP, VEA, Fermi levels, and chemical hardness, are proportional to the spatial structure and the Au/Pd atomic ratio of the mixed clusters. A very large electronic charge transfer from Pd to Au was found for the binary clusters, indicating a bonding interaction between Au and Pd atoms in the mixed cluster. The electronic properties of the Au-Pd binary clusters reveal that the reactivity of the Au-Pd binary clusters toward small molecules, such as O2, H2, and CO, is higher than that of the pure ld clusters.

The generalized gradient approximation (GGA) method based on density functional theory (DFT) was used to analyze the structural stability and electronic properties of the unconventional carbon halogen fullerenes C56X10(X=F, Cl, Br, I). The investigation of structural stability indicates that the evolution of energy gaps, the reactive heat (△E), the maximal vibration frequencies, and the minimal vibration frequencies of C56X10(X=F, Cl, Br, I) all decrease with an increase in the atomic number of X. This indicates that the stabilities should decrease from C56F10 to C56I10. C56F10 is the most stable molecule among the four molecules and we predict that it can be isolated and synthesized because of the successful isolation of C56Cl10. From the analysis of the frontier orbitals of C56 and C56X10(X=F, Cl, Br, I), the C atoms are located at the abutting penta n sites and both the hexa n-hexa n-penta n vertex functions are the most active sites on C56 and this is suitable for halogen atom attachment. Our calculations also show that the electronegativity of C56X10(X=F, Cl, Br, I) cluster molecules decrease with an increase in the atomic number of X. However, the electronegativity of the C—X fragment in the molecules is affected by its location.

The molecular structures and antioxidant activities of a novel flavonoid-type compound (lespedezaflavonone) from Lespedeza virgata were studied using density functional theory (DFT) with the B3LYP exchange correlation functional. The optimized geometries of neutral, radical cation, radical, and anion forms of lespedezaflavonone were obtained. Ring A was found to be responsible for the high activity of the flavonoids by an analysis of the character of the frontier molecular orbital, which was consistent with what was observed experimentally. Furthermore, it was noteworthy that ring A' was firstly found to be the important part for the potent antioxidant activity of lespedezaflavonone. To quantify the antioxidant activities, we determined the adiabatic ionization potential (IP, 509.0, 432.2 kJ·mol-1 for the neutral and anion forms, respectively), the homolytic O—H bond dissociation enthalpy (BDE, 347.3 kJ·mol-1) for lespedezaflavonone, the adiabatic electron affinity (EA, -620.6 kJ·mol-1) and the H-atom affinity (HA, -487.5 kJ·mol-1) for hydroxyl radical in aqueous solution. Our theoretical analysis shows that H-atomtransfer, stepwise electron-transfer-proton-transfer, and sequential proton-loss-electron-transfer mechanisms for lespedezaflavonone to scavenge hydroxyl radical may occur thermodynamically in parallel, while the last process is the most favorable. These findings are helpful for further study on the design of novel efficient flavonoid-type antioxidants, the structure-activity relationship and the antioxidant mechanismof flavonoid-type compounds.

Hormone-sensitive lipase (HSL) is known as the key rate-limiting enzyme responsible for regulating free fatty acids (FFAs) metabolismin adipose tissue. Recently, HSLhas been found to be useful in the treatment of diabetes so the discovery of new HSL inhibitors (HSLIs) is of interest. Methods for the prediction of HSLIs are highly desired to facilitate the design of novel diabetes therapeutic agents because limited knowledge exists concerning the mechanism and three dimensional (3D) structure of hormone-sensitive lipase. We have explored several machine learning methods (support vectormachines (SVM), k-nearest neighbor (k-NN), and C4.5 decision tree (C4.5 DT)) to predict desirable HSLIs from a comprehensive set of known HSLIs and non-HSLIs. Our prediction system was tested using 252 compounds (123 HSLIs and 129 non-HSLIs) and these are significantly more diverse in chemical structure than those in other studies. The recursive feature elimination selection method was used to improve the prediction accuracy and to select the molecular descriptors responsible for distinguishing HSLIs and non-HSLIs. Prediction accuracies were 85.7%-90.5% for HSLIs, 63.2%-68.4% for non-HSLIs, and 75.0%-80.0% for all structures based on three kinds of machine learning methods using an independent validation set. SVMgave the best total accuracy of 80.0% for all the structures. This work suggests that machine learning methods such as SVM are useful to predict the potential HSLIs among unknown sets of compounds and to characterize the molecular descriptors associated with HSLIs.

The Na+-G-quadruplex complex is a polarized system and the mobility of Na+ during its formation or decomposition is still unclear. The atombond electronegativity equalization method at the σπ level fused into molecular mechanics (ABEEMσπ/MM) model clearly defines the lone-pair electron, σ bond and π bond sites in addition to the atomic sites. The partial charge fluctuation is calculated in accordance with a change in the molecular environment and so this method should account well for the polarization effect. In this paper, we discuss some properties for the Na+-G-tetrad complex including its geometry, charge distribution, and binding energy according to the ABEEMσπ/MM method. We also investigate these properties for the Na+-G-tetrad complex using the ab initio method at the MP2/6-31G(d,p) level. The ABEEMσπ/MM results are in od agreement with the ab initio results. The presence of Na+ changes the hydrogen bonds in the G-tetrad. By comparing the binding energy of the systemfor every Na+ mobile path, we predict that the most probable path is that three Na+ ions move away individually from the G-quadruplex along the α orientation. This study lays a solid foundation for the dynamic simulation of ion exchange channels in a G-quadruplex using the ABEEMσπ/MM model.

The vibrational bioresonance (VBR) and its control in a calciumion oscillation systemunder the influence of low-frequency and high-frequency signals were studied. Results show that calcium ion oscillations consist of two peaks (VBR) under the influence of a low-frequency signal and that the amplitude increases under the influence of a high-frequency signal. The weak signal with lower frequency and higher amplitude is more likely to be amplified during VBR. Close to the Hopf bifurcation point (small control parameter threshold), VBR is weak and the maximum amplitude of the high-frequency signal gradually shifts to higher values. The feedback mechanism plays an important role in the amplification and suppression of VBR during the formation of calcium waves in cells. A positive feedback mechanism, therefore, enhances the VBR while a negative feedback mechanism decreases the VBR. Furthermore, when noise is introduced into the system, the stochastic resonance (SR) suppresses the VBR and influences the number of vibrational resonance (VR) peaks. A critical level of noise exists for different resonant behaviors and when the noise intensity is below a critical level VBR occurs, while above the critical level a single VR peak appears.

A cholesterol modified fullerene (CHL-C60) was synthesized using the Bingel-Hirsch reaction and was characterized by nuclear magnetic resonance (NMR), mass spectra (MS), elemental analysis (EA). Results of UV-Vis spectrumand fluorescence spectrumindicate that CHL-C60 forms an inclusion complex with γ-cyclodextrin (γ-CD) due to the strong interaction between γ-cyclodextrin and the steroid ring. The water solubility of CHL-C60 is enhanced significantly. CHL-C60 can dissociate from cyclodextrin and subsequently bind to human serum albumin (HSA) and bovine serum albumin (BSA) with association constants of 5.73×104 and 7.05×104 L·moL-1, respectively. The efficiency of desoxyribonucleic acid (DNA) photocleavage for CHL-C60/γ-CD is as high as 60.5% under anaerobic conditions, which is caused by photoinduced electron transfer frompBR322 plasmid DNA to CHL-C60.

TiO2 thin films were patterned froman aqueous solution containing Ti(SO4)2 by chemical bath deposition and electrochemical deposition methods. Two titanium precursors were prepared, a titanium sulfate solution (pH=1.0) and a peroxotitanium sulfate solution (pH=1.6), and these solutions were stabilized by sulfuric acid and hydrogen peroxide, respectively. Pre-patterned self-assembled monolayers (SAMs) were micro-contact printed on silicon substrates and were then immersed in the chemical bath for deposition to obtain the ordered TiO2 patterns. The inorganic ligands affect the solution stability and the crystallinity of the TiO2 films. The aqueous acidity affected the quality of the patterned films. A peroxotitanium sulfate solution was also used for patterning on the conductive glass of indium tin oxide by electrodeposition. The photoresist was ready for deposition after spin-coating, exposure, and development. Finally, clear patterns with a height of 200 nmwere fabricated by controlling the cathode potential.

Based on the catalytic property of palladium, GaN nanowires were fabricated by ammoniating Pd:Ga2O3 thin films at 950 ℃, which were deposited onto a Si(111) substrate by radio frequency (RF) magnetron sputtering. Scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM), and high-resolution transmission electron microscopy (HRTEM) were used to characterize the structure, morphology, and composition of the samples. Results reveal that the nanowires are single-crystal GaN with a hexa nal wurtzite structure and they have diameters ranging from 20 to 60 nm with lengths of up to several tens of micrometers. Moreover, most of the GaN nanowires have a smooth surface without any impurities and are of high crystal quality. The optical properties of the samples were measured by photoluminescence spectroscopy and three emission bands with peaks at 361.1, 388.6, and 426.3 nm were observed. Additionally, the bandgap UV light emission has a weak blue shift compared to the bulk GaN. We briefly discuss the growth mechanismof the GaN nanowires.

CdS nanorods were successfully synthesized by pyrolysis using trioctylphosphine (TOP) as a coordinating solvent. For this pyrolysis, cadmium acetate dihydrate and sulfur powder were used as the cadmium source and sulfur source, respectively. The structure, morphology, and optical properties of the prepared samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), ultraviolet-visible (UV-Vis) spectroscopy, photoluminescence (PL), Fourier transform infrared (FTIR) spectroscopy, and nuclear magnetic resonance (NMR) 31P spectroscopy. The effects of different molar ratios of Cd-to-S and the reaction concentrations on the morphology and size of the CdS nanostructures were investigated. The results indicated that the wurtzite CdS nanorods, with a typical diameter of 4.5 nm and a length of up to 28.0 nm, had a preferential [001] growth direction and displayed a quantum confinement effect. We also proposed a possible formation mechanismfor the CdS nanocrystals based on the experimental results.

The hybrid mesoporous materials, PW11/SBA-15, were synthesized using tetraethoxysilane (TEOS) and lacunary polyoxometalate Na7PW11O39 (PW11) by a co-condensation approach in the presence of triblock copolymer EO20PO70EO20 (P123) as a template. The resultant materials were characterized by infrared (IR) spectroscopy, UV-Vis diffuse reflectance spectroscopy (UV-Vis/DRS), powder X-ray diffraction (XRD), N2 adsorption-desorption, and transmission electronmicroscopy (TEM). Results show that the Keggin units are retained perfectly and grafted onto the pore walls of the mesoporous silica by covalent linkage, and an ordered hexa nal packing of channels with homogeneous pore diameters is obtained in the materials. The prehydrolysis time of TEOS influences the construction of the ordered mesostructure significantly. The long-range ordered mesophase increases as the prehydrolysis time increases because of the salt-out effect of PW11, which is associated with solubility of the polyoxometalate precursors.

Manganese oxides show huge structural flexibility and appear in various crystallographic polymorphs. Hence, morphological and phase control of desired manganese oxide nanostructures could enable their properties to be tuned with a greater versatility, and endow them with potential applications. Herein, we report a simple hydrothermal route for the synthesis of various MnO2 nanostructures using Mn3O4 powder as raw material. The obtained products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Results show that in H2SO4 solution, urchin-like γ-MnO2 nanostructures and single-crystal β-MnO2 nanorods are obtained at 80 and 180 ℃, respectively. In addition, MnOOH nanowires were obtained in a dilute acid solution. The influence of synthetic parameters including temperature, acidity, and reaction time are discussed. The γ-MnO2 intermediate might play an important role in the formation of nanorods. The evolution of phases and morphologies in the reaction process suggested the anisotropic crystal growth for the formation of nanostructures under acidic conditions.

Ordered mesoporous MgZnO was synthesized using mesoporous carbon CMK-3 as hard template and Mg(NO3)2·6H2Oaswell as Zn(NO3)2·6H2Oas precursors forM and ZnO, respectively. The morphology and mesoporous structure of the as-prepared MgZnO were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and N2 adsorption-desorption. The results demonstrate that MgZnO has a highly ordered mesoporous structure as well as crystalline pore walls. The average pore size is about 4.0 nm and the BET surface area is about 114.5 m2·g-1. Additionally, wide angle XRD results indicate that a solid solution of M and ZnO is formed. As a semiconductor material, mesoporous MgZnO has potential application in optical devices.