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Simultaneous removal of SO2, NOx and Hg0 using O3 and corn stalk bio-charcoal (CR)/coconut shell activated carbon (CS) was compared in a fixed bed. The effects of temperature, adsorption time and ratio of O3/NO on the removal efficiency of NO, Hg0 and SO2 by CR/CS were studied, and the CR and CS was characterized and analyzed. The results indicated that the oxidation rate of NO and Hg0 increased with the increase of O3/NO ratio, while the oxidation rate of SO2 first increased and then decreased slightly. The increase of temperature inhibits the oxidation of NO but promotes the oxidation of Hg0 and SO2. At 140°C and O3/NO ratio was 1.4, the oxidation rate of NO, Hg0 and SO2 is 99%, 78.6% and 3.5%, respectively. As O3/NO ratio increased from 0.4 to 1.4, the removal efficiency of CR for NOx increased from 4.6% to 93%, and CS increases from 4.5% to 79%. CR and CS can reduce part of NO2 and increase NO concentration at the outlet. NOx adsorption performance on CR is relatively better, while those of Hg0 and SO2 on CS are relatively stronger. CS has stronger physical adsorption capacity than CR. The relative content of oxygen-containing functional groups C-O and C=O on the surface of CR is higher than that of CS, while its relative content of COOH and O=C-O is lower.

AD730TM is a novel superalloy developed for the hot section part in aero engine and gas turbine machinery with enhanced performance. The material is characterized by its excellent high temperature properties for being an alloy possible to manufacture by cast and wrought process compared to other superalloys in the same class such as Inconel718. The material with higher temperature capability means potentially increased energy efficiency as well as less emission in the new engine design. However, there is lack of information on machinability of the material, especially achievable surface quality under high speed machining. Machining process is commonly employed in the manufacturing of hot section part, such as turbine disc, to obtain the final surface quality and tolerance. Surface quality produced by the machining processes is one of the crucial factors to determine the functional performance and correspondent fatigue life time of the parts. The paper will present the results of surface characterization of the part produced by high speed turning with CBN tool. A series machining tests were conducted in the study. Surface morphology on machined samples were investigated with a scanning electron microscope to assess the surface damages and other surface defects induced by the machining processes. 3D surface topology was also analyzed with an Infinite-focus-variant microscope to correlate with machining condition. In addition, effect of tool wear and cutting parameters, such as cutting speed, will also be discussed in the paper. (Less)

The “thermal effect” of the green roof system on the pollutant dilution process would be analyzed in this research. Different arrangement schemes (on the rooftop, windward side and leeward side) of the green roof system would alter the thermal buoyancy distribution in the street canyon, thus change the overall flow field and pollutant dilution condition Computational Fluid Dynamics (CFD) technique along with the Renormalization Group (RNG) k-e turbulence model has been adopted for the simulation work. Cases without the green roof system are assumed to be uniformly heated and are prepared for benchmark comparisons. Six aspect ratios (H/W) and ten ranks of unstable thermal stratifications (Rb) are selected to consider the influence of street canyon morphology and thermal buoyancy. Results demonstrate that the lateral deployment of green roof system performs better than the rooftop deployment and the situations without green roof system. In the windward cooling cases, a single vortex is formed in the canyon center and dramatically reduces the pollutant retention time τ when H/W > 1, while in the leeward cooling cases, a “free airflow” region is formed in all the tested aspect ratios expect for H/W = 0.5. The rooftop deployment scheme has negative effects, not just decaying ventilation performance, but also delaying pollutant dispersion period. Present research could benefit the rational design of the green roof system in the urban building clusters, and further enhance its cooling capacity for the built energy conservation.

This study reports on the synthesis, X-ray structure, magnetic properties, and computational studies of the complex [Mn3O(mhaep)3(MeOH)3](ClO4) (1), where the ligand H2mhaep is a 2-N,N-[methyl(2-hydroxymethyl)aminoethyl]phenol moiety. Compound 1 crystallizes in the trigonal space group P 3 - . The most significant structural characteristic is that the Jahn-Teller axes of the MnIII ions tilt to an angle of 47.6°. Calculations using the ORCA program, combined with irreducible representation methods indicate that, the leading terms of the molecular zero-field splitting (zfs), D and E terms, are largely quenched. The conclusion was confirmed by reduced magnetization measurements, which indicate that the magnitude of the D term is very limited. All of the magnetic data and the computational calculations point to a conclusion that compound 1 is ferromagnetically coupled with a total molecular spin of S = 6.

Broadcast is an important operation in Cognitive Radio Networks (CRNs). How to achieve broadcast in an energy-efficient way is important since users in CRNs are usually battery-powered. Existing single-channel broadcast mechanisms are not suitable for CRNs because multiple channels can be used in a CRN. Most existing multi-channel broadcast schemes rely on a common control channel (CCC) to support broadcast. However, finding such a CCC in a CRN is difficult because an unlicensed user's available channels are changed over time and space. In this paper, we focus on an environment where no broadcast structure or CCC is established in advance while a node is equipped with one CR transceiver and does not aware of the locations and distances to other nodes. We have defined the one-hop Minimum Multichannel Set Cover (MMSC) problem and the multi-hop Minimum Cost Broadcast (MCB) problem in such an environment. Both problems are NP-hard and we have proposed a heuristic solution, the Energy-Efficient Broadcast (EEB) protocol, to solve them. Considering the uncertain primary user occupancy issue, the EEB protocol features a distributed solution that uses only local information. Simulation results verify that EEB effectively reduces energy consumption and achieves high packet delivery ratio.

Drug-drug interactions have become a serious problem in the clinic, since plant-based medicines are extensively used. The present study investigated the effects of Ziziphus jujuba fruit (ZJ) extract on the pharmacokinetics of phenacetin, a typical substrate of a cytochrome P450 enzyme CYP 1A2, in rats. The rats were pretreated with the water extract (1.0 g · kg(-1)) or the ethanolic extract (3.6 g · kg(-1)) of ZJ for 10 days, and the pharmacokinetics of phenacetin was investigated after intravenous administration. In an in vitro assay, acetaminophen formation in the hepatic microsomes of ZJ-treated rats was investigated to assess CYP1A2 activity. Our results demonstrated that the treatment with the water and ethanolic extracts of ZJ decreased the plasma concentration of phenacetin and increased the plasma concentration of acetaminophen, resulting in a 43.2% and 15.5% reduction in the AUC0-120 of phenacetin, respectively, and a 53.2% and 64.9% increase in the AUC0-120 of acetaminophen, respectively after intravenous administration. The water or ethanolic extract of ZJ significantly increased the clearance of phenacetin and acetaminophen formation in hepatic microsomes. In conclusion, ZJ extracts displayed effects on the pharmacokinetics of phenacetin and increased the CYP1A2 activity in rats. Therefore, precaution on drug-drug interactions should be taken when ZJ is co-administered with drugs metabolized by CYP1A2, which may result in decreased concentrations of these drugs.

The reaction of 1,2,4-benzenetricarboxylic acid (H3btc), as a ligand, under pH-controlled hydrothermal conditions with nickel salts leads to the formation of a coordination polymer of {CsNi3(OH)(H2O)3[C6H3(CO2)3]2·3H2O}n (1). The subunit of compound 1 contains a hydroxide- and carboxylate-bridged trinickel clusters that are linked by an unsymmetrical organic carboxylate spacer to form a chiral three-dimensional anionic framework, in which cesium cations and guest water molecules are located in one-dimensional channels. The presence of a hydroxide ion serves both as a deprotonation agent and a cation source during the hydrothermal reaction, thus permitting the extent of deprotonation of the unsymmetrical ligand H3btc to be controlled, which is essential for the successful formation of compound 1. The magnetic properties of compound 1 were analyzed. Both dc and ac magnetic susceptibility as well as reduced magnetization measurements confirmed the spin-frustration nature of 1.

This paper is devoted to give the connections between Carleson measures for Besov-Sobolev spaces B-p(sigma)(B) and p-Carleson measure in the unit ball of Cm. As applications, we characterize the Riemann-Stieltjes operators and multipliers acting on B-p(sigma)(B) spaces by means of Carleson measures for B-p(sigma)(B).

In this paper, a simple two-step approach for redox protein immobilization was introduced. Firstly, alkynyl-terminated film was formed on electrode surface by electrochemical reduction of 4-ethylnylphenyl (4-EP) diazonium compound. Then, horseradish peroxidase (HRP) modified with azido group was covalently immobilized onto the electrografted film via click reaction. Reflection absorption infrared (RAIR) spectroscopy and electrochemical methods were used to characterize the modification process. The results indicate that HRP retains its native structure and shows fast direct electron transfer. Moreover, the immobilized HRP shows excellent electrocatalytic reduction activity toward H(2)O(2) with a linear range of 5.0×10(-6) to 9.3×10(-4) mol L(-1).

This paper is devoted to characterizing the Riemann-Stieltjes operators and pointwise multipliers acting on Mobius invariant spaces Q(p), which unify BMOA and Bloch space in the scale of p. The boundedness and compactness of these operators on Q(p) spaces are determined by means of an embedding theorem, i.e. Q(p) spaces boundedly embedded in the non-isotropic tent type spaces T-q(infinity). (C) 2010 Elsevier Inc. All rights reserved.

A simple and versatile method based on noncovalent supramolecular attachment and layer-by-layer (LBL) assembly is proposed to prepare nanostructured hybrid conducting polymer. The negatively charged poly(sodium 4-styrenesulfonate) (PSS) wrapped multiwalled carbon nanotubes (MWCNTs) is doped with cationic polyaniline (PANI) nanofibers via LBL assembly, and a well-defined PANI/MWCNTs composite was obtained. The LBL assembly process is characterized by scanning electron microscopy, energy dispersive spectrometry and electrochemical methods. It was found that PSS wrapped MWCNTs inside the multilayer film can dope nanostructured PANI effectively and shift its electroactivity to a neutral pH environment. Moreover, the conducting composites show amperometric response for hydrogen peroxide with a linear range of 2.0 × 10 −7 –1.0 × 10 −3 mol L −1 .

In this paper, a simple, facile and general strategy was proposed for the covalent biofunctionalization of Au surface with hemoglobin (Hb). Structurally well-defined azide-terminated organic self-assembled monolayers (SAMs) were formed on Au surface from a mixture solution of azidoundecanethiol and dilute thiol. 4-Pentynoic acid was used as a bifunctional linker to immobilized Hb via a selective, reliable, robust click reaction and a widely used carbodiimide reaction. The surface modification was characterized by reflectance absorption infrared (RAIR) spectroscopy, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The experimental data indicate that the proposed methodology is a highly versatile strategy for quantitative, stable and covalent attachment of biomacromolecules onto solid interface. The Hb functionalized Au electrode shows a pair of well-defined and quasi-reversible peaks at about -0.210 V (vs. SCE) in 0.1 mol/L pH 5.0 buffers, which stands for the reduction and oxidation of Hb Fe(III)/Fe(II) redox couple. The electron transfer rate constant (k(s)) was estimated to be 0.78 s(-1). The maximal surface coverage (Gamma) of the immobilized Hb was 8.3 x 10(-12) mol cm(-2), indicating the formation of a monolayer. Moreover, the biocatalytic activity of the Hb biofunctonalized electrode was investigated and an excellent electrocatalytic reduction toward O(2) and H(2)O(2) was observed.

In this paper, we described a simple and facile method for the covalent functionalization of Au surface with nitrophenyl group via stepwise strategy. Structurally well-defined azide-terminated organic self-assembled monolayers (SAMs) were formed on Au surface from a commercially available mixture solution of azidoundecanethiol and dilute thiol. Subsequent, derivatization of the azide-terminated monolayers was conducted in aqueous environments with ethynyl nitrobenzene via a selective, reliable, robust click reaction. By this way, the nitrophenyl group was covalently and quantitatively grafted on Au surface, which was confirmed by Raman Spectrometry and electrochemical methods. These results demonstrated the efficiency of using click chemistry in assembling covalently linked nanostructures. Keywords: Click reaction, Covalent grafting, Self-assembled monolayers, Nitrophenyl group, Azidoundecanethiol

Axially substituted tin phthalocyanines, namely dichloride-tetra-(α-pentyloxy) tin (IV) phthalocyanine 2, dihydroxy-tetra-(α-pentyloxy) tin (IV) phthalocyanine 3 and its dimmer di-μ-oxo- tetra-(α-pentyloxy) tin(IV) phthalocyanine 4 were synthesized. The catalytic effect of H2O-free CaCl2 in quinoline was used for condensation of dihydroxy tin phthalocyanine 3 to the cofacially array dimmer 4. Their structures were characterized by UV–vis, IR, elemental analysis, MS, as well as 1HNMR spectroscopy.

In this paper, the pointwise multipliers M ( D τ , Q p ) and M ( D τ , Q p , 0 ) are characterized in the unit ball of C n for the values of τ , p in the three cases: (i) τ n , n − 1 n p ⩽ 1 , (ii) τ = n , n − 1 n p ⩽ 1 , and (iii) τ > n , n − 1 n p ⩽ 1 . In particular, the multiplier spaces M ( D τ , BMOA ) and M ( D τ , VMOA ) are discussed correspondingly for all τ, and the sharp embeddings of M ( D n , BMOA ) and M ( D n , VMOA ) in α-Bloch spaces are shown, respectively.

A novel anthraquinone phthalocyanine Al(Ⅲ) 4 and Co(Ⅱ) 5 were synthesized and characterized by elemental analysis, IR, UV/ vis, 1H NMR, HPLC and MS. The photophysical properties of the two metal complexes were studied and compared by fluorescence spectrum method.

Polymer-supported phosphine ligand 3b derived from ferrocene was prepared, and applied in palladium-catalyzed Suzuki–Miyaura reactions. A range of aryl bromides can couple with phenylboronic acid to obtain corresponding biaryls in excellent yields. The recycling of the polymer-bound catalyst was tested without adding palladium.

Ag+-doped ZnS nanocrystals surface-capped with thiourea (expressed as ZnS: Ag/thiourea) were synthesized through sol-gel method with thiourea as a surface modifier and characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), X-ray fluorescence spectrum (XRF), infrared spectrum (IR), UV-Vis absorption spectrum(UV-Vis), and photoluminescence spectrum (PL). The results show that Ag+ ions are doped in ZnS nanocrys-tals, and the sulfur atoms in thiourea molecules coordinate with metal ions on the surface of the nanocrystals. The spherical ZnS: Ag/thiourea nanocrystals with an average diameter of 5 nm have good fluorescent characteristics, and therefore have great potential for use in molecular assembly and novel luminescence materials.