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The heterojunction of ZnO was deposited on hydrogenated TiO2 nanotube arrays (H–TiO2) by atomic layer deposition (ALD) with various cycles. The ZnO was uniformly wrapped with the H–TiO2 samples and the thickness could be accurately controlled by the cycle numbers of ALD. The higher growth rate ~2.7 A/cycle was obtained due to the surface amorphous layer, compared with the air-treated samples (A-TiO2), ~2.3 A/cycle. When the cycle numbers increased to 200, nanowire arrays appeared. Interestingly, the absorption in the visible light region improved more significantly when ALD ZnO was employed for the H–TiO2 rather than the A-TiO2 samples. The H–TiO2 samples with 42 nm of ALD ZnO exhibited enhanced photoelectrochemical water splitting performances, compared with the A-TiO2 with 42 nm of ALD ZnO. This was related to the higher degree of the electronic band bending and improved photo-response in the UV and visible light region, resulting from the oxygen vacancies.

Tumor denervation limits cancer growth, but the mechanisms behind this are unknown. We find that malignant melanoma cells interact with pain-initiating nociceptor neurons by increasing neurite outgrowth, responsiveness to noxious ligands and neuropeptide release. In turn, nociceptor-produced neuropeptides increase exhaustion of cytotoxic T cells (PD1+Lag3+Tim3+INFγ-), limiting their capacity to eliminate melanoma cells. Genetic TRPV1 or NaV1.8 lineage ablation, local pharmacological silencing as well as blockade of vesicle release from tumor-innervating nociceptors enhance tumor-infiltrating leukocyte (TIL) numbers and increase survival of mice subject to orthotropic melanoma inoculation, blunting tumor growth and TIL exhaustion. We conclude that reducing neuropeptide release from tumor-innervating nociceptors, by eliminating their immunomodulatory action on cytotoxic CD8 T cell, may be a useful therapeutic intervention to boost immune surveillance.

Ni nanoparticles were deposited on to black TiO2 nanowire arrays by atomic layer deposition (ALD) using Ni(dmap)2 (dmp = dimethylamino-2-propoxide) as precursors. The size of the Ni nanoparticles was well controlled by the number of ALD cycles. The growth rate of the nanoparticles on the black TiO2 nanowire arrays was 0.5 A/cycle, which was comparable with that on the pristine samples, even though a surface amorphous layer was formed. When the Ni ALD was applied to the pristine and black TiO2 nanowire arrays, both samples exhibited an enhanced absorption in the visible light range. Interestingly, the maximum absorption was observed for the black TiO2 nanowire arrays due to the higher polarization that induced the stronger surface plasmon resonance (SPR) of the Ni nanoparticles. The wavelength of the absorption red shifted from 440 to 500 nm when the cycle number increased from 25 to 100. The highest intensity of the absorption was obtained for 50 cycles of Ni ALD. This was attributed to the inter-particle interaction related to the size and loading density of the Ni nanoparticles. 50 cycles of Ni ALD on the black TiO2 nanowire arrays exhibited the most effective photoresponse in the visible light range, resulting in a higher carrier concentration. As a consequence, a superior photoelectrochemical water splitting property was obtained.

The effects of sodium content and hydrogenation of TiO2 nanotubes on their photocatalytic activity were investigated. TiO2 nanotubes with different contents of sodium were prepared by an alkaline reflux method, followed by washing with different concentrations of acid. When a hydrogen thermal treatment was applied to the nanotubes, the white nanotubes with and without sodium would transform into blue polyhedral and light yellow chain-like structures, respectively. UV–vis absorption spectra indicated that a higher absorption in the visible light range was obtained for the blue polyhedral structure. Interestingly, an amorphous surface layer and Ti3+ species appeared and became more pronounced when the sodium was removed completely. This led to the formation of a defect energy band belt, which not only narrowed the band gap but lowered the rate of recombination of photo electrons and holes. As a consequence, a higher rate of photocatalytic decomposition of methanol for hydrogen evolution under visible light illumination were obtained.

We used force-field based grand-canonical Monte Carlo simulation method and density functional theory to study adsorption characteristics of carbon dioxide (CO2) molecules in a metal-organic framework (MOF) compound, [Zn(bdc)(dpds)]n. The studied MOF include a metal ion (Zn(II)), an anion organic linker (dianion of benzene dicarboxylicacid, bdc2−) and a neutral organic linker (4,4′-dipyridyldisulfide, dpds). Results from calculated adsorption isotherms and enthalpies of adsorption agree with the experimental data. The interactions between the adsorbed CO2 and the organic linkers were examined in simulations. Calculated results show available absorption sites are surrounded by two dpds ligands in which an S-S bond as an N-N′ spacer connect two pyridines. In contrast, the bdc2− ligand does not give a significant contribution to the substantial adsorption amount even though it contains the carboxylate group that provides available bonding site to CO2.

The voltage fade on lithium-rich layered oxides could be alleviated by substitution of Mn and Ni for Cr. A series of Cr substituted lithium-rich layered oxides, (Li1.2Mn0.6-xNi0.2-xCr2xO2, x = 0, 0.03, 0.065, and 0.1) was prepared by the ethylenediaminetetraacetic acid (EDTA) sol-gel method. For x = 0.03, the reduced voltage fade and a superior capacity retention were obtained, leading to a higher specific energy. When x increased to 0.1, the sample exhibited a comparable voltage fade behavior with the pristine Ni-Mn oxide. The alleviation of the voltage fade was attributed to the suppression of the phase transformation from layer to spinel structures. The reason for this was due to both the reduction of the oxygen loss from the lattice and a decreased content of Mn3+ at the first charge. Because of the combined effect of these two factors, the conversion of layered oxides to spinel was suppressed, resulting in the alleviation of the voltage fade.

Due to the development of femtocell technologies, indoor LTE/LTE-A signal quality can be significantly improved. However, since femtocells and macrocell are deployed into a coexisted heterogeneous network, handoff from macrocell to femtocell turns out to be one of the major design issues to achieve better user experience provided by femtocells. In general, the macrocell user equipment (MUE) selects a handoff target femtocell base station (FBS) in the handoff procedure solely based on the received signal strength indicator (RSSI), signal to interference plus noise ratio (SINR), or signal to noise ratio (SNR). Although this approach is very simple and easy to implement, it can result in load imbalance among FBSs. Hence, this paper proposes a novel game-based handoff mechanism that combines the modified Dutch Auction (MDA) and stochastic election process (SEP) to jointly take the uplink and downlink signal qualities and load balance of the handoff candidate FBSs into consideration when selecting handoff target FBS. Besides, in order to speed up the execution of the handoff mechanism and reduce the percentage of handoff failures, the Fast SEP and Go Back B are further developed, respectively. Simulation results confirm that the proposed MDA+Fast SEP+Go Back B handoff mechanism provides better load balance, faster handoff and higher percentage of successful handoffs.

Lotus leaves are pretreated by exposure to hydrochloric acid (HCl) by several methods, including mild (PHT), hydrothermal (HHT), and mild and hydrothermal (PHHT) treatments, and subsequently pyrolyzed to yield hard carbon materials. The hydrothermal pretreatment produces the most substantial impact on the microstructures, surface compositions, and electrochemical performances of the resulting hard carbons. Materials prepared by the HHT pretreatment exhibit carbon microspheres with the largest graphene interlayer spacing, lowest quantities of oxygen functional groups, and no observable inorganic impurities. Moreover, such materials exhibit initial coulombic efficiencies and discharge capacities of 66% and 250 mA h g−1, respectively, at 0.2 C rate and after 100 cycles, which are significantly higher than those of non-treated hard carbons (53% and 162 mA hg−1). Surprisingly, the HHT pretreated materials show a maximum discharge capacity of 58 mA h g−1 at a current density of 20 C, while the non-treated materials show no detectable discharge capacity. The superior charging rates of the HHT-treated materials originate from surface properties that facilitate rapid charging processes. Specifically, these capabilities arise from a less reactive surface and larger pore volume that reduce the resistance of the solid electrolyte interphase (SEI) and enhance the diffusivity of sodium ions.

In this study, divinylbenzene (DVB) was used as the cross-linker to prepare alkyl methacrylate (AlMA) monoliths for incorporating π-π interactions between the aromatic analytes and AlMA-DVB monolithic stationary phases in capillary LC analysis. Various AlMA/DVB ratios were investigated to prepare a series of 30% AlMA-DVB monolithic stationary phases in fused-silica capillaries (250-μm i.d.). The physical properties (such as porosity, permeability, and column efficiency) of the synthesized AlMA-DVB monolithic columns were investigated for characterization. Isocratic elution of phenol derivatives was first employed to evaluate the suitability of the prepared AlMA-DVB columns for small molecule separation. The run-to-run (0.16-1.20%, RSD; n = 3) and column-to-column (0.26-2.95%, RSD; n = 3) repeatabilities on retention times were also examined using the selected AlMA-DVB monolithic columns. The π-π interactions between the aromatic ring and the DVB-based stationary phase offered better recognition on polar analytes with aromatic moieties, which resulted in better separation resolution of aromatic analytes on the AlMA-DVB monolithic columns. In order to demonstrate the capability of potential environmental and/or food safety applications, eight phenylurea herbicides with single benzene ring and seven sulfonamide antibiotics with polyaromatic moieties were analyzed using the selected AlMA-DVB monolithic columns.

TiO2 film was coated on acid-treated and pristine multiwall carbon nanotubes (CNTs) with different thicknesses by atomic layer deposition at 100 °C to form a CNT/TiO2 core-shell structure. The relationship between oxygen-containing functional groups on the surface of CNTs and growth rate of TiO2 film was studied. The saturation growth rate of TiO2 was 0.55 A/cycle for acid-treated CNTs with sufficient durations of pulse time for the precursors of TiCl4 and H2O. The as-prepared TiO2 film was amorphous, and the anatase and rutile phases of TiO2 were obtained by heating to 300 °C and 800 °C, respectively. The shell thickness of anatase TiO2 on CNTs was a key factor to determine the efficiency of methylene blue (MB) degradation. The thickness of 22 nm exhibited the best efficiency of MB degradation due to lower electron-hole recombination rate and higher amount of hydroxyl group generated on the surface of TiO2 after UV irradiation.

We show that in layered oxides that are employed as cathodes in lithium-ion batteries, the cation layers can order on different {111}NaCl planes within a single particle, which makes the lithium layer discontinuous across a particle. The findings challenge previous assertions that lithium undergoes 2-D diffusion in layered oxides and the data provide new insights into the decrease in rate capabilities for some layered oxides. Therefore, it is critically important to understand how these discontinuities form and how the loss of 2-D diffusion impacts the overall performance of the layered oxide cathode materials. Employing X-ray diffraction (XRD) and aberration-corrected scanning transmission electron microscopy (STEM), we find that as the material transitions from a disordered to an ordered state, it forms four orientation variants corresponding to the four {111}NaCl planes. This transition is not intrinsic to all layered oxides and appears to be more strongly affected by nickel. Furthermore, with energy dispersive spectroscopy (EDS), we show that there is an increase in the nickel concentration at the interface between each orientation variant. This reduces the rate of lithium diffusion, negatively affects the rate capability, and could be contributing to the overall capacity fade.

The surfaces of the lithium-rich layered oxide cathodes (Li1.2Mn0.6Ni0.2O2, LLO) were modified with nanolaminated ZnO–TiO2 ultra-thin films (1.7 ± 0.4 nm) by atomic layer deposition (ALD) with various coating sequences. The layered oxide cathodes were coated with (I) ALD TiO2, followed by ZnO (P@T@Z), (II) ALD ZnO, followed by TiO2 (P@Z@T), and (III) ALD TiO2, followed by ZnO and TiO2 (P@T@Z@T). Among the nanolaminated coatings, a uniform coating was only obtained for the P@Z@T samples due to the outer layer-like growth of ALD TiO2. Surprisingly, the P@Z@T samples exhibited superior electrochemical performances and thermal stabilities to the other samples. The samples possessed a higher initial specific discharge capacity of 123 mAh g−1 at 1 C, and a capacity retention of 97% after 80 charge-discharge cycles, in comparison with the pristine samples, which were 100 mAh g−1 and 68%, respectively. When the current density increased to 5 and 10 C rate, the samples possessed the specific discharge capacities of 134 and 103 mAh g−1, but the capacities were absent for the pristine samples. The samples charging at 4.8 V withstood a higher decomposition temperature of 267 °C and a lower heat release of 62.4 J/g compared to the pristine samples, 260 °C with 253.6 J/g. The enhanced rate capability and cyclability of the P@Z@T samples were related to the decreased resistance from 1894 to 847 Ωcm−2 and less side reactions. This was due to the uniform surface and complete protection of the nanolaminated film.

Surface microstructures of porous carbon (PC) derived from waste tea leaves were manipulated by using ZnCl2, KOH and H3PO4 as activating agents. The PCs with various surface microstructures were used as hosts for sulfur, and their electrochemical performances were investigated systematically. The KOH activated carbon exhibited not only a maximum specific surface area, 2287.3 m2g−1 but also a broadened pore size distribution, 2.60 to 3.87 nm, as well as a large pore volume, 1.273 cm3g−1, leading to a high sulfur content, 71 wt%. Interestingly, the KOH activated carbon‑sulfur composite (CS) exhibited superior electrochemical performances. The initial discharge capacity under 0.1C, 1350 mA h g−1 was obtained. After 100 cycles under 0.2C, the capacity of 750 mA h g−1 was maintained. When the current density increased to a 1C the capacity of 728 mA h g−1 was reached, but only capacities of 360 mA h g−1 and 264 mAhg−1 were reached, respectively, for the ZnCl2-and H3PO4-CS samples. The improved electrochemical performances were due to the lowest resistance of charge transfer from the SEI layer (Rs) and the interfacial electrons (Rct). Both reduced resistances were attributed to the microstructural features that suppress the polysulfide dissolution.

Dye-sensitized solar cell (DSSC) is appealing to renewable energy communities because of its attractive features of low cost, facile assembly and short energy payback time. Nevertheless, the commonly used platinum as the counter electrode (CE) encounters great difficulties in its scarcity and noble nature. Herein, we demonstrate a promising and facile route to attain an earth-abundant, high-conductivity Pt-free flexible CE with the controllable catalytic activity via the atomic layer deposition (ALD) of ZnO as the nanoscale sacrificial template. Our result reveals the electrocatalytic activity of carbon cloth as a function of surface morphology can be successfully tailored by the ALD cycle. It can be ascribed to the interplay of ZnO and carbon during carbothermic reduction, offering the synergetic effects of the defects and oxygen doping on the carbon cloth surface as the enhanced catalytic sites for the regeneration of triiodide into iodide. As a proof of concept, the DSSC using the activated carbon cloth via ALD is enabled to deliver a boosted conversion efficiency by 79%, as compared with that using pristine carbon cloth. Such a promising route can open up a perspective for reaching an earth-abundant, high-conductivity carbon-based flexible CE with the superior catalytic activity for the photoelectrochemical cells.

The integration of WiMAX networks and multi-protocol label switching (MPLS) networks, called WiMPLS networks, is the trend for nomadic Internet access in the fourth generation (4G) wireless networks. The base station (BS) in such heterogeneous networks will play the role of bridge and router between the IEEE 802.16 subscriber stations (SSs) and MPLS networks. However, there is no such integrated solution so far and the switching efficiency of the BS should be considered as well. This paper, therefore, adopts a cross-layer fashion (from network layer to MAC layer) to design the end-to-end label switching protocol (ELSP) for filling this gap. ELSP provides the mechanism of end-to-end (SS-to-SS) and layer 2 switching transfer for switching performance enhancement by assigning the SS with the MPLS labels (M-labels). The M-label can be carried by the IEEE 802.16e extended subheader within the MAC protocol data unit (MPDU), which is fully compliant with the IEEE 802.16e standard. The security issue caused by M-label usage is also concerned and solved in this paper. This paper also reveals an extra advantage that the switching delay of the BS achieved by ELSP can be as low as hardware-accelerated IP lookup mechanism, e.g., ternary content addressable memory (TCAM). Simulation results show that ELSP efficiently improves the end-to-end transfer delay as well as the throughput for WiMPLS heterogeneous networks.

Platinum nanoparticles as a catalyst for proton-exchange-membrane fuel cells (PEMFCs) were grown on nitric acid-treated multiwalled carbon nanotubes by atomic layer deposition (ALD) at 250 °C. Formation of uniform and well-distributed Pt nanoparticles was achieved. The size and number of Pt nanoparticles could be controlled by the ALD cycle number. The PEMFC test shows that for the membrane electrode assembly made of both anode- and cathode-deposited Pt (0.019 and 0.044 mg cm −2 , respectively) after 100 cycles of ALD has 11 times higher specific power density than that made of commercial E-Tek electrodes containing 0.5 mg cm −2 of Pt.

In this paper, the methods based on Lyapunov stability theorem to study the stability and switching law design for the T–S fuzzy switched systems with state-driven switching method are presented. Furthermore, these methods can be applied to cases when all individual systems are unstable. The PDC is employed to design fuzzy controllers from the T–S fuzzy models. The stabilization analysis is reduced to a problem of finding a common Lyapunov function for a set of linear matrix inequalities. Finally, a numerical example and an illustrative example based on the chemical process example are given to show the merits of the proposed approach, respectively.

Streptococcal pyrogenic exotoxin B (SPE B) is a cysteine protease expressed by Streptococcus pyogenes. The D9N, G163S, G163S/A172S, and G239D mutant proteins were expressed to study the effect of the allelic variants on their protease activity. In contrast to other mutants, the G239D mutant was ∼12-fold less active. The Gly-239 residue is located within the C-terminal S230-G239 region, which cannot be observed in the x-ray structure. The three-dimensional structure and backbone dynamics of the 28-kDa mature SPE B (mSPE B) were determined. Unlike the x-ray structure of the 40-kDa zymogen SPE B (proSPE B), we observed the interactions between the C-terminal loop and the active site residues in mSPE B. The structural differences between mSPE B and proSPE B were the conformation of the C-terminal loop and the orientation of the catalytic His-195 residue, suggesting that activation and inactivation of SPE B is involved in the His-195 side-chain rotation. Dynamics analysis of mSPE B and the mSPE B/inhibitor complexes showed that the catalytic and C-terminal loops were the most flexible regions with low order parameter values of 0.5 to 0.8 and exhibited the motion on the ps/ns timescale. These findings suggest that the flexible C-terminal loop of SPE B may play an important role in controlling the substrate binding, resulting in its broad substrate specificity.

Under some rank condition, a new version of bounded real lemma, which is expressed in terms of an admissible solution of a generalized discrete-time algebraic Riccati equation (GDARE) rather than inequality, is presented for linear discrete-time descriptor systems. When a linear discrete-time descriptor system is admissible, with the H∞-norm of its transfer matrix less than a prescribed positive number γ, a constructive procedure is also given to obtain an admissible solution of the above-mentioned GDARE.

A series of coordination polymers, [M(C 5 O 5 )(dpe)] (M = Mn 1 , Fe 2 , Cd 3 and Co 4 ; dpe = 1,2-bis(4-pyridyl)ethane) with a 2D metal–organic framework (MOF) has been synthesized and characterized by single-crystal X-ray diffraction studies. Structural determination reveals that compounds 1 – 4 are isostructural and possess a 2D brick-wall-like layered framework with a rectangle grid as the basic building unit through the connectivity of metal ions with μ 3 -, μ 4 -croconates and anti -dpe ligands. Two 2D layers are then cross-linkaged by gauche -dpe ligands to complete a 2D bi-layered MOF and then extended to a 3D supramolecular architecture through π–π and C–H⋯O interactions between the croconate and pyridyl rings of dpe, which exhibit high thermo-stability and keep their crystalline forms up to 350 °C. The magnetic exchange coupling between the metal centers for compounds 1 , 2 and 4 was analyzed and based on the Curie–Weiss expression and a binuclear magnetic model. The negative values of the Weiss constant and the magnetic exchange coupling constant indicate the antiferromagnetic nature between the metal ions via the bridges of bis-bidentate adjacent μ 3 -croconate ligands.

Intra and intermolecular interactions of heptasulfur imide (S7NH) are investigated in terms of topological properties analyses, such analyses are applied to both experimental (multipole model) and theoretically calculated (DFT and PDFT calculations) charge densities of the isolated molecule and of the crystal. The same analyses are also applied to a multipole model density obtained from theoretically (PDFT) derived structural amplitudes. The covalent bond character of S–N, N–H and S–S bonds are well described in terms of density, rb, and total energy density, Hb, at the bond critical point rc, though it is clear that the S–S bonds are weaker shared interactions than those of N–H and S–N bonds. Lone pair electron regions of sulfur and nitrogen atoms are revealed as the local charge concentration site from the Laplacian of charge density. The even weaker intermolecular interactions are well characterized; these include the N–H/S hydrogen bonding, N/S binding interactions and S/S binding interactions. All these intermolecular binding interactions are closed-shell interactions. The Laplacian of charge density demonstrates a directional intermolecular binding interaction. The corresponding intermolecular binding energies are derived by MP2/6-311CG(d,p) calculations. Atomic graph of each atom of the molecule is described in detail by the vertices, edges and faces of the polyhedron around the nucleus to illustrate such directional interactions. q 2004 Elsevier Ltd. All rights reserved.

A new mixed-ligands metal-coordination polymer, [Cd(C4O4)(bipy)(H2O)2] (1), (bipy=4,4′-bipyridine), was synthesized under hydrothermal condition and characterized by X-ray diffraction method. A three-dimensional interpenetrating network with one-dimensional channels intercalating water molecules undergoes a reversible hydration-dehydration process upon a cooling-heating cycles associated with distinct color change and structural variation.

Two coordination polymers with the formula of [M 2 (DPA) 2 (C 4 O 4 )(C 2 O 4 )] ∞ (M=Cu 1 , Zn 2 ; DPA=dipyridylamine) were synthesized under hydrothermal conditions. Both complexes are crystallized in triclinic system, space group P 1 with the cell parameters: a=8.3078(3) A , b=9.1192(3) A , c=9.2316(3) A , α=115.164(1)°, β=94.283(1)°, γ=103.559(1)°, V=603.17(4) A 3 , Z=2 for complex 1 and a=8.5348(2) A , b=9.0451(2) A , c=9.0862(3) A , α=114.305(1)°, β=100.493(1)°, γ=97.318(1)°, V=612.34(2) A 3 , Z=2 for complex 2 , respectively. X-ray single-crystal structural determinations reveal that these two complexes are both composed of one-dimensional zigzag chains built up via the [M(DPA)] 2+ fragments and alternately bridged bidentate μ 1,3 -C 4 O 4 2− , tetradentate C 2 O 4 2− ligands. The coordination environments of the M(II) centers adopt a slightly distorted trigonal bipyramid bonded with two N atoms of DPA, one O atom of squatate and two O atoms of oxalates. The intrachains N–H⋯O and C–H⋯O hydrogen bonds play an important role on the additional stabilization in constructing the open frameworks.

The metal string complexes with di!erent metal ions and various lengths have been successfully synthesized and structurally characterized. The crystal and molecular structure of nonanickel complex [Ni 9 (l 9 -(peptea) 4 Cl 2 ] which is the longest metal string at this moment will be reported. Crystal data for [Ni 9 (l 9 -(peptea) 4 Cl 2 ](C 2 H 4 Cl 2 ) 10 : Space group, monoclinic C 2/c, a"27.0453(6), b"42.6678(5), c"37.4268(6) As , b"109.539(1)3

The synthesis, electronic structure and X-ray crystal analysis of [Pt(TPrPc)] (H2TPrPc = 2,7,12,17-tetrapropylporphycene) and described. The structure of [Pt(TPrPc)] is similar to that of its NiII analogue except for the increase in the distance between the two bipyrrole moieties.