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Detecting the underlying performance of hydrated electrons and hydroxyl radicals in the cationic water cluster can greatly help to understand the inter reaction mechanism in the liquid water and aqueous solutions. Based on our previous (H2O)10+ research, we have paid attention to more problems of larger cationic clusters in this work, including the existence of hemibonded type, long-range correction functions, and hydrogen-bonded site analyses. The lower-energy structures of the cationic water cluster (H2O)12+ have been comprehensively explored, and more experienced functions are introduced to check the ground state and vibration spectrum. Unlike the configuration regularity of neutral (H2O)12 clusters and small cationic water clusters, those new-found structures for (H2O)12+ are inclined to adopt three dimension (3D) cage-like structures and the H2O-OH2 structure appears in the higher energy isomer. The calculation reveals that the lowest stable isomer is the 3D cage structure W14 predicted at MP2 level, which has not been reported yet. In the thermal simulation, structure transition from the cage-like to the ring-like occurs at T > ≈256 K, and the two dimension (2D) ring-like structure occupies a dominant position at high temperature range. The infrared spectra explain that the difference of the spectra between the 2D net structures and 3D cage-structures is mainly caused by the weight fluctuation of single acceptor-single donor (AD), double acceptor-single donor (AAD), and single acceptor-double donor (ADD) sites in these isomers. This further gives a similarity relation between (H2O)12+ and H+(H2O)12 clusters in the shape of the network and spectral characteristics. By molecular orbitals and topological analysis, we find that the lone pair orbital on hydroxyl radical dominates the reactivity and stability of cationic system. The present research may be helpful for exploring the evolution law of the larger cationic water clusters in the future.

A novel organic/inorganic hybrid which consisted of N,N-diphenyl-4-(2,2':6′,2″-tepyridin-4-yl)aniline (abbreviated as TPPA) and CdS nanoparticles (NPs) had been prepared through interfacial coordination effect according to soft-hard-acid-base principle. The interfacial coupling coordination was analyzed by XRD, far-IR, FT-IR and HRTEM, which resulted in changeable morphology and tunable linear/nonlinear optical properties. Upon interfacial coordination, the hybrid showed a red-shifted (55 nm) UV–vis absorption band, weakened single photon fluorescence emission (84% decrease), and enhanced two-photon absorption cross-section (13 folds). Due to excellent two-photon absorbing character, the hybrid had good application in the field of optical power limiting with 43 W⋅cm−2 limiting threshold. The regulation mechanism of optical properties was thoroughly discussed upon single crystal structure of the interfacial coordination complex and quantum calculation, as well as the growing mechanism of the hybrid.

Raspberry subcultured tissue seedlings were used as test materials for the effect of different concentrations of graphene on the growth of raspberry seedlings and the development of adventitious roots. The graphene was characterized by a laser particle size analyzer, STEM, TEM, XPS and Raman spectroscopy. A root analysis system and SEM were used to systematically characterize the seedling height, root length, root specific surface area, number of branches, number of root tips and root micromorphology, thus determining the optimum concentration of graphene for the growth of raspberry tissue culture seedlings. The results showed that with increasing graphene concentration, the seedling height, root length, root tip number and root specific surface area of the seedlings all showed a trend of first increasing and then decreasing. The optimum concentration of graphene was 2 mg·L-1, the seedling height of tissue culture seedlings was 1.46 times that of the control group, and the root length, specific surface area, number of root tips and their bifurcation number were about twice that of the control group.

The FJCA series jet flotation cells, which have the independent intellectual property rights of China, are different from the conventional mechanical-agitation flotation cells. Therefore, the magnification practice of the FJCA series jet flotation cells shall not simply copy from the conventional approach of the mechanical-agitation flotation cells. Instead, new magnification principles for the jet flotation cells need to be developed. Three principles of the magnification of the FJCA series jet flotation cells are introduced in this article: 1. the similarity of the fluid dynamics and kinetics of the coal slurry; 2. the similarity of the geometries of the aeration agitator; 3. the similarity of the boundary parameters of the flowing velocity of the slurry. The first principle, which employs the circulation flowrate per unit volume as the base parameter of the similarity of fluid dynamics and kinetics, is considered as the most critical one for the magnification of the FJCA series jet flotation cells.

Several studies have suggested that sodium intake may affect blood pressure (BP), proteinuria, and intrarenal transforming growth factor-β1 (TGF-β1) production in patients and animal models with chronic kidney disease (CKD). The Chinese population has a high prevalence of CKD and is well known for consuming salty foods. This study will investigate the role of dietary sodium intake on BP control among non-dialysis Chinese CKD patients.A cross-sectional study was carried out in a cohort of 176 non-dialysis hypertensive CKD patients to investigate their sodium intake and its effect on BP control by measuring 24-h urine sodium excretion (24-h UNa). A total of 20 patients with immunoglobulin A nephropathy (IgAN) participated in a 7-day sodium restriction study (100 mmol/day). Their changes in BP, proteinuria, and urinary TGF-β1 excretion were subsequently analyzed. Another 23 IgAN patients without salt restriction were included as controls.The average 24-h UNa of the study cohort was 149.0 ± 66.4 mmol/day. Only 31.8% patients had a 24-h UNa less than 100 mmol/day. The OR for each 17 mmol increment in 24-h UNa (salt 1 g/day) for BP130/80 mmHg was 1.26 (95% CI 1.10-1.44, P = 0.001). The sodium restriction group achieved significantly more reduction in SBP (-11.1 mmHg vs. -5.0 mmHg, P = 0.022), DBP (-9.4 mmHg vs. -2.1 mmHg, P = 0.009), and urine protein excretion [-465 (-855 to -340) mg/day vs. -150 (-570 to 40) mg/day, P = 0.024]. A positive correlation was observed between the change of 24-h UNa and the change of SBP (r = 0.450, P = 0.047) in the sodium restriction group. The change of 24-h UNa was also correlated with the 24-h TGF-β1 excretion (r = 0.558, P = 0.011) in these patients.Dietary sodium intake restriction should be monitored and intensified in the treatment of Chinese CKD patients.

As one of the main disasters in mine explosion, gas explosion is a chain chemical fast-reaction. Combustion chain reaction is inhibited by gas explosion suppression technique, which controls the explosive development and reduces the damage of explosion artificially. Based on the experimental research, the study compared and analysed the type K and S condensed aerosol's impact on the explosive limits of methane concentration and the critical oxygen concentration of methane explosion. The results show that with the increase of aerosol concentration, the methane explosion limits is decreased. Different concentrations or types of aerosol have different effects on methane explosion. When the concentration of S aerosol is 315 mg/L, the methane won’t explode. On the same of aerosol concentration, S aerosol has a better explosion suppression effect than K.

In this article, the influence of reaction conditions on the aromatization over nano-HZSM-5 zeolite catalyst was investigated. The experimental results showed that nano-HZSM-5 catalyst has the best aromatization properties under the optimal conditions: reaction temperature 430°C, reaction pressure 0.3 MPa, and liquid hourly space velocity 1 h−1. At the optimal operational conditions, the conversion of olefins in the feedstock was 76.15%. Aromatics yield and the content of olefins, content of aromatics, and content of isoparaffins in liquid product were up to 84.98%, 12.11%, 39.58%, and 35.23%, respectively.

The etherification experiment for FCC light gasoline on transition metals modified Hβ zeolite was studied in a fixed-bed reactor. The effect of preparation condition of catalyst on the catalyst's activity, stability, and the effect of reaction temperature, methanol/tert-olefin molar ratio, and liquid hour space velocity on the etherification reaction were discussed. The experimental results showed that the different metals modified Hβ zeolite had different etherification performances. And the conversion of tertiary carbon-olefins of the molybdenum modified Hβ zeolite, which was loaded 3%, was higher 6.0% than the Hβ zeolite. The optimal reaction conditions were temperature 70–80°C, liquid hour space velocity 1.0 h−1 and methanol/tert-olefin molar ratio 1.05. The modified Hβ zeolite catalysts possessed favorable prospect for its higher stability.

In this work, a new approach for TMPyP [5,10,15,20-tetrakis (1-methylpyridinium-4-yl) porphyrin] and TMAPP [5,10,15,20-tetrakis (N,N,N-trimethyl-anilinium-4-yl) porphyrin] intercalation into α-phase of zirconium hydrogen phosphate (α-ZrP) was described: porphyrins were inserted through exchanging pre-intercalated alkylamine. Pre-intercalated n-butylamine (BA) could form either a mobile monolayer or a stable bilayer in α-ZrP. The exchange speed between porphyrins and BA in mobile monolayer is obviously faster than that in stable bilayer. Therefore mobility of spacers is one important intercalation factor. In addition, we investigated the interlayer state of TMPyP by XRD, visible spectrum, fluorescence spectrum and molecular modeling. The results collectively revealed that the porphyrin was orderly arranged with their planes inclined to the host lamella and was presented as monomer instead of aggregation in the gallery of α-ZrP.

Reaction of anhydrous YbCl3 with 2 equiv. of sodium 2,4,6-tri-tert-butylphenoxide (ArONa, Ar=C6H2-t-Bu3-2,4,6) and 2 equiv. of potassium diphenyl amide in THF afforded the first bis(aryloxo) amido-lanthanide complex of (ArO)2Yb(NPh2)2K(THF)4 (1). In 1, the ytterbium and potassium were bridged via diphenyl amido ligands. The ytterbium metal center was coordinated to two oxygen atoms of aryloxide ligands and two nitrogen atoms of diphenyl amido ligands in a conventional distorted tetrahedral fashion, while the potassium interacted in η2-fashion with two phenyl rings of the diphenyl amido ligands besides four THF molecules. 1 displayed moderate catalytic activities for the polymerization of methyl methacrylate and acrylonitrile.

A catalyst is provided for the selective hydrogenation of dienes from fluid catalytic cracking gasoline. There are a small quantity of dienes in fluid catalytic cracking gasoline which can deteriorate the quality of fluid catalytic cracking gasoline, as well as make its further process inconvenient. These dienes must be reduced as impurity. In this paper, the nickel supported on alumina selective hydrogenation catalysts modified with magnesium promoter are prepared by impregnation method. The fluid catalytic cracking gasoline (

In this paper, the FCC gasoline (75∼120○C fraction) is investigated and studied on the HZSM-5 type zerolite catalysts modified with zinc nitrate and ammonium dihydrogen phosphate which are prepared by impregnation method. The results show that Znx–HZSM-5 type zerolite catalysts have a high initial reactivity of aromatization but a rapid deactivation. Compared to Znx–HZSM-5 type zerolite catalysts, the Znx–Py–HZSM-5 type zerolite catalysts not only have more stable reactivity of aromatization but a property of isomerization. The Zn (2%)–P(4%)–HZSM-5 has the best performance among them. Also, the reaction operational conditions are observed and studied on the Zn (2%)–P (4%)–HZSM-5 type zerolite catalyst. The results are that the optimal reaction temperature is 430○C, the liquid hours space velocity (LHSV) is 1 hr−1 and the reaction pressure is 0.1Mpa.

The intermolecular interaction potential for methane–argon complex is calculated by local density approximation (LDA) approaches. The calculated potential has a minimum when the intermolecular distance of methane–argon complex is 6.75 a.u.; the corresponding depth of the potential is 0.0163eV which has good agreement with experimental data. We also have made a nonlinear fitting of our results for the Lennard-Jones (12-6) potential function and obtain that V(R) = 143794365.332/R12−3032.093/R6 (R in a.u. and V(R) in eV).

Composite absorbent (CAds-AC-15) mainly used activated carbon and CaCl2 as the resources for adsorption refrigeration were prepared by the mixed method, and the content of activated carbon in CAds-AC-15 was 15%. Adsorption isotherms of ammonia on CAds-AC-15 were determined by positive gravimetric method. Adsorption - desorption cycle performance and cooling characteristics of CAds-AC-15-ammonia working pair was evaluated by self-made adsorption - desorption measuring device. Experimental results show that the equilibrium capacity of ammonia on the CAds-AC-15 is up to 1.136kg/kgads at 30?, which is 5% lower than that of CaCl2. With the conditions of adsorption temperature 30?, ammonia evaporation pressure 0.25 MPa, desorption temperature 300?, the performance of CAds-AC-15- ammonia working pair is stable after repetitious adsorption-desorption cycles, adsorption capacity of ammonia on the CAds-AC-15 and its cyclic adsorption capacity is 0.55~0.65 kg/kg and 0.2~0.25 kg/kg, respectively. The cooling capacity is up to 328.38kJ/kgads, which is twice as high as CaCl2 - ammonia working pair.

National Natural Science Foundation of China [40976050]; National Public Benefit (Ocean) Research Foundation of China [201105013]; Grand Research Foundation of Fujian Province [2011YZ0001-1]

Effects of high pressure (6 GPa) on the solid state phase transformation kinetic parameters of aluminum bronze during the cooling process are investigated, based on the measurement and calculation of its solid state phase transformation temperature, duration and activation energy and the observation of its microstructures. The results show that high pressure treatment can reduce the solid phase transformation temperature and activation energy in the cooling process and can shorten the phase transformation duration, which is favorable when forming fine-grained aluminum bronze.

The characteristic of microscopic plasticity associated with collapse of helium bubble and void in single-crystal aluminum under the same shock loading strength has been investigated by molecular dynamics (MD) simulations. The results show that both the helium bubble and the void collapse through the emission of shear dislocation loops, while prismatic dislocation loops are never observed in the simulations. The preferential dislocation nucleation sites are similar for the helium bubbles and the voids, but the number of dislocations emitted from the helium bubble outnumbers that from the voids, and the dislocation loops emitted from the helium bubbles move faster than that from the voids. Meanwhile, it is more difficult to emit dislocation loops from the leading side (the side which the shock hits first) of both the helium bubbles and the voids than from the trailing side. By analysing the resolved shear stress along the slip plane, we found that the internal pressure of the helium bubbles increase the resolved shear stress and make the dislocation emission from the helium bubbles much easier than from the voids. The curvature change from the leading side to the trailing side produced by the shock modifies the critical shear stress for dislocation nucleation, which explains the difference in the plasticity between the leading side and the tailing side of both the helium bubbles and the voids. The result will contribute to a better understanding of the microscopic mechanism through which irradiation damages affect the dynamic properties of metals.

We have investigated the phase transition, the structural and the thermodynamic properties of AlAs in three crystallographic structures, i.e. B3 （zinc blende）, B1 （rocksalt）, and B8 （nickel arsenide）, at high pressures by using the full-potential linearized muffin-tin orbital scheme in the framework of density functional theory. By taking the common tangent to the energy-volume curves of B3-B8 and B3-B1 structures, we obtain a pressure of about 5.44 GPa for the transition from B3 to B8 and forecast a transition pressure of about 6.46 GPa for the transition from B3 to B1. We have also investigated the structural properties of B8 under high pressures, the results show that c/a ratio keeps nearly constant （～0.2% fluctuation） when V/V0≈0.7—1.05; c/a ratio increases linearly with the value of V/V0 decreasing when V/V0≈0.4—0.7. The relation between relative volume V/V0 and pressure P is obtained by fitting equation of state （EOS）, and the EOS of B8 accords well with measurements. Finally according to quasi-harmonic Debye model the dependences of bulk module B on pressure P and heat capacity CV on temperature T under different pressures are successfully obtained.

The elastic properties of helium-bubble embedded aluminum have been investigated by molecular dynamics simulation. First, the interaction potentials between aluminum and helium atoms are parametrized with the help of first-principle method. Secondly, we studied the influence of helium bubble on the elastic properties of aluminum from the following two aspects: the size of helium bubble (the diameters being 16, 20, 25, 30 and 3.5nm, respectively) and the internal pressure of helium bubble (the ratios of the number of helium atoms to the vacancies being about 5%, 15%, 45% and 85%, respectively). The results show that the elastic constants c11, c12 and c44 decrease with increasing diameter of helium bubble, however, for a fixed size they are almost independent of the internal pressure of helium bubble. Using the elastic composite system model, the influence of the size and internal pressure of helium bubble on aluminum is explained qualitatively based on the analytical results and is consistent with our calculated results.

The preparation of silicon nanoporous pillar array (Si-NPA) and Fe3O 4 coated Si-NPA (Fe3O4/Si-NPA) is presented. The morphologies and microstructures of the two kinds of thin films were characterized and their corresponding capacit ive humidity sensing properties investigated. It was shown that both Si-NPA and Fe3O4/Si-NPA are typical micron/nanometer structural compo site systems. When the relative humidity increased from 11% to 95%, the capacitances reached 1500% and 5500% of their initial values measured with 100 Hz signal frequency, and 800% and 12000% measured with 1000 Hz signal frequency, for Si-NPA and Fe3O4/S i-NPA, respectively. At the same time, both of the two thin films exhibited quic k response speed, the response times in the humidity-increment and humidity-decr ement processes were determined to be 15 s and 5 s for Si-NPA, and 20 s and 15 s for Fe3O4/Si-NPA, respectively. These excellent humidity sensing properties of Si-NPA and Fe3O4/Si-NPA are explained based on thei r corresponding morph ological and structural properties. Our experiments strongly indicated that Si-N PA is an ideal thin film both for direct humidity sensing and as a substrate for growing composite humidity sensing materials.