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A new type of explosive ink formulation that can be quickly cured was prepared with unsaturated polyester as binder, styrene as active monomer, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide as photoinitiator, and hexanitrohexaazaisowurtzitane (CL-20) as the main explosive. Then the explosive ink direct writing technology was used to charge the micro-sized energetic devices, the curing mechanism of the explosive ink was discussed, and the microstructure, safety performance and explosive transfer performance of the explosive ink molded samples were tested and analyzed. Results indicate that the composite material has a fast curing molding speed, its hardness can reach 2H within 8 min. The crystal form of CL-20 in the molded sample is still e type. The CL-20 based UV-curing explosive ink formulation has good compatibility, its apparent activation energy is increased by about 3.5 kJ/mol. The composite presents a significant reduction in impact sensitivity and its characteristic drop height can reach 39.8 cm, which is about 3 times higher than the raw material. When the line width of charge is 1.0 mm, the critical thickness of the explosion can reach 0.015 mm, and the explosion velocity is 7129 m/s when the charge density is 1.612 g/cm3.

As a kind of rare materials, nano-silver has broad application prospects in the fields of catalysis, medical treatment, new energy and so on. However, there are few reports on the systematic research of nano-silver in ceramic glazes. In this work, different color ceramic glazes were produced by tuning the nano-silver content and optimizing the firing process. The crystalline phase composition, micro-morphology and elemental distribution of fired glazes were analyzed and discussed in depth. The elemental composition and distribution of the samples were studied. The surface of the glazes with varying Ag contents fired under the reducing atmosphere exhibited blue-white. And the blue color is attributable to Rayleigh scattering that may arise because the phase-separation structures existed in glazes. Interestingly, the color of the ceramic glazes with varying Ag contents changed to golden-yellow when the ceramic glazes were fired under the air atmosphere. Golden-yellow color of the samples fired under the air atmosphere is mainly attributable to the silver nano-particles, though Ag+ may be existed in the glazes.

The promoting effect of metal oxides to Pt catalysts toward methanol oxidation reaction (MOR) has attracted widespread attention in recent years. In this communication, we report the promoting effect of MoO3 to Pt catalyst by rationally designing and tuning the nanostructure of the catalysts. MoO3 nanorods are firstly synthesized through hydrothermal method and used as the substrate for the deposition of polyaniline (PANI) layer. The PANI-MoO3 composite nanostructures are then used as the support for Pt catalyst. Depending on the preparation method of Pt nanoparticles, the nanostructure can be PANI nanotube supported Pt (Pt/PANI) through etching MoO3 nanorods with NaBH4 and PANI-MoO3 composite nanorods supported Pt (Pt/PANI-MoO3). The catalytic properties of the two catalysts toward MOR are investigated. Results show that the current of methanol oxidation on Pt/PANI-MoO3 catalyst is comparable to that on Pt/PANI, while the peak potential of MOR on the former is lowered by 180 mV as compared with the latter, suggesting a much higher catalytic activity of Pt/PANI-MoO3. The presence of MoO3 may be responsible for the improvement of the catalytic properties through the co-synergistic effects of PANI and MoO3.

A Faraday isolator based on magnetically biased graphene is proposed and analyzed. The isolator consists of two rectangular waveguides, two circular-rectangular transitions and a circular cylindrical waveguide loaded multiple graphene sheets, with a static magnetic field which parallel to the signal transmission direction biased. The principles of the isolator have been investigated using the mode-matching technique. The isolation is calculated by the signal flow diagram combined with the transmission matrix method. The theoretical results show that its isolation is more than 30 dB in the working frequency (1.8 GHz–2.2 GHz). The isolation can be tuned by varying the chemical potential or varying the magnetic field. The novel isolator has a simple structure and a wider bandwidth compared to the conventional Faraday isolator. Simultaneously the transmission direction of the isolator can be changed easily by changing the direction of the magnetic field.

Pt-Ir/IrO2-PtO2 composite with an overlapping structure as oxygen-electrode catalyst has been prepared by doping Ir into Pt, doping Pt into IrO2, and then making the two layers combined with each other. This structure helps achieve positive interior modification on Pt and IrO2 and active coupling effect between PtIr ~ PtIrO2 layers. Electrochemical analyses show that Pt-Ir/IrO2-PtO2 possesses 81.4% higher ORR activity and 45.5% higher OER activity than Pt/IrO2 catalyst. Pt-Ir/IrO2-PtO2 especially exhibits remarkable ORR and OER durabilities in life tests, which are attributed to the stable overlapping structure.

In order to solve the problem of low sample forming efficiency and uncontrollable crystal type in inkjet printing, a formula of explosive ink suitable for micro-spraying is designed by using hexanitrohexaazaisowurtzitane (CL-20) as the main explosive, the compound of polyazide glycidyl ether and ethyl cellulose as the bonding system, ethyl acetate as the solvent, and the refined e-CL-20 as the seed crystal in this paper. The optimal process conditions were determined, and under the optimal process conditions, the explosive ink is written on an aluminum substrate or a glass substrate by micro-spraying direct writing technology, and CL-20 based energetic thin film forming samples are characterized. The results show that the CL-20 crystal form in the sample is e type and the molding effect is good. The optimum process conditions are as follows: the nozzle has an air pressure of 0.02 MPa, the height is 40 mm, the spraying rate is 0.4 ml min−1, and the substrate temperature is 50°C. The explosive particles in the energetic thin films are spherical. The particle size is about 10 µm, and the particle size distribution is relatively uniform. The density of the composite is 1.567 g cm−3, and the molding density can reach 80.2% of the theoretical density. The activation energy is 242.07 kJ mol−1. The characteristic drop height H50 is 38.5 cm. When the charge width is 0.8 mm, the critical size of the detonation is 0.8 × 0.03 mm2. The detonation wave formed after the shaped sample is detonated in a small groove with a cross-sectional dimension of 1.0 × 1.0 mm2 can successfully pass through multiple continuous 90° charging corners.

Filter characteristics of a planar Mach–Zehnder interferometer (MZI) structure composed of periodically thin corrugated metal films were studied here. From theoretical simulation, spoof surface plasmon polaritons can propagate along the periodically thin corrugated metal films in microwave frequency, which can be excited by a coplanar waveguide. When the two arms of the MZI have the same length with the angle between them being 60°, the MZI structure has a very wide bandwidth with 8.6 GHz. By changing the length of one of the interference arms, a novel low-pass filter based on the planar MZI structure with two notched frequencies was proposed. The proposed planar structure can find potential applications in developing surface wave devices in integrated microwave circuits and systems.

A core–shell nanostructure (Pt–PdAg/C–D) with dealloyed PdAg nanoparticles (PdAg/C–D) as the core and a Pt monolayer as the shell is prepared and employed as an electrocatalyst toward oxygen reduction reaction (ORR). Compared with its counterpart alloyed PdAg core-Pt monolayer shell catalyst (Pt–PdAg/C), the Pt–PdAg/C–D catalyst shows significantly higher catalytic activities for ORR. The half wave potential (E1/2) on Pt–PdAg/C–D is located at −0.17 V, which is comparable to that on the commercial Pt/C catalyst and ca. 30 mV more positive than that on Pt–PdAg/C. The MSA of Pt in Pt–PdAg/C–D is 171.8 A gPd+Pt−1, which is 3.2 and 2.4 times higher than those of Pt–PdAg/C and commercial Pt/C catalysts, respectively. The Pt monolayer shell on the surface of the nanoparticles would induce much higher utilization of Pt atoms, and the dealloying process would result in a nanostructured PdAg core with a rough surface and a Pt shell with a numbers of low-coordinated atoms. It is concluded that the change in the electronic and geometric structure of Pt in the Pt–PdAg/C–D catalyst may contribute to the increase in catalytic performance for ORR.

In the present work, we report the syntheses of IrO2 nanoparticles with SBA-15 template (s-IrO2), and s-IrO2 supported Pt nanocomposite (Pt/s-IrO2) as bifunctional oxygen catalyst. Physical characterizations including X-ray diffraction and transmission electron microscopy demonstrate that s-IrO2 catalyst has excellent uniformity and regularity in particle shape and much ordered distribution in geometric space, and Pt/s-IrO2 catalyst shows a uniform Pt dispersion on the surface of the s-IrO2 particles. Electrochemical analyses prove that s-IrO2 catalyst possesses superior OER activity at operating potentials; and that Pt/s-IrO2 catalyst, in comparison to Pt/commercial IrO2, has higher ESA value and ORR catalytic performance with a mechanism of four-electron pathway and a high ORR efficiency. And as a bifunctional oxygen catalyst, Pt/s-IrO2 also exhibits more remarkable OER performance than the commercial one. The s-IrO2 nanoparticles will be a promising active component (for OER), and suitable for Pt support (for ORR).

Graphene has many novel properties such as the ability of guiding plasmonic wave at terahertz (THz) frequencies, chemical potential shift as the carrier density changed. Since carrier density of graphene can be modified by bias voltage, the coupling coefficients or propagation loss of graphene plasmon can be modulated easily. A compact wideband terahertz modulator is proposed to modulate and guide plasmonic waves. The surface plasmon polariton (SPP) propagation and the modulation depth in the graphene biased structure are numerically investigated. The proposed THz plasmonic modulator has a wide working band about 1 THz and its modulation depth reaches about 76% at the frequency of 8 THz, which have potential application in THz communication.

Parallel coupled filter based on spoof surface plasmon polaritons is presented in this letter. Designed on a thin dielectric substrate, the ultrathin metallic structure is composed of rectangle drilled hole metal strip. A planar spoof SPPs parallel coupled resonator has been integrated into the drilled hole metallic strip to produce narrow. We simulate the parallel coupled filter in microwave frequency band. The simulate results show that the filter has two narrow pass-band, the equivalent relative bandwidth (6.8%), the central frequency (5.9 GHz), the insertion loss is above −3dB in the passband from 5.7 to 6.1 GHz, and the equivalent relative bandwidth (2.3%), the central frequency (17.1GHz), the insertion loss is above −3dB in the passband from 16.9 to 17.3GHz. Due to planar structures proposed here, it is easy to integrate in the microwave integrated systems, which can play an important role in the microwave communication circuit and system.

A microwave power divider based on spoof surface plasmon polaritons was presented here. The proposed divider was composed of two different sizes of periodic circular hole array metal strips on a substrate with relative dielectric constant of 3.3, loss angle of 0.003 and thickness of 0.76 mm. Compared to rectangular hole and rectangular groove, the dispersion curve of circular hole was more deviated from the light line and the cut-off frequency was lowest. The simulated results show the S21 and S31 of the power divider are equal and about 3dB with the cut-off frequency of 10.8 GHz which means the input power is divided into two outports equally. According to the planar structure, the proposed divider has some significant advantages such as high confinement, adjustability and easy integration which can play an important role in the microwave communication circuits and systems.

Although organic light-emitting devices have been commercialized as flat panel displays since 1997, only singlet excitons were emitted. Full use of singlet and triplet excitons, electrophosphorescence, has attracted increasing attentions after the premier work made by Forrest, Thompson, and co-workers. In fact, red electrophosphorescent dye has already been used in sub-display of commercial mobile phones since 2003. Highly efficient green phosphorescent dye is now undergoing of commercialization. Very recently, blue phosphorescence approaching the theoretical efficiency has also been achieved, which may overcome the final obstacle against the commercialization of full color display and white light sources from phosphorescent materials. Combining light out-coupling structures with highly efficient phosphors (shown in the table-of-contents image), white emission with an efficiency matching that of fluorescent tubes (90 lm/W) has now been realized. It is possible to tune the color to the true white region by changing to a deep blue emitter and corresponding wide gap host and transporting material for the blue phosphor. In this article, recent progresses in red, green, blue, and white electrophosphorescent materials for OLEDs are reviewed, with special emphasis on blue electrophosphorescent materials.

The feed rate, specific mechanical energy (SME), and product properties of rice extruded with soybean oil, cellulose, and SiO 2 were investigated using a co-rotating twin-screw extruder. A reduction in both feed rate and SME were observed with increase in soybean oil levels. Decreases in feed rate were observed with increase in cellulose levels up to 8% and SiO 2 levels up to 2%. Decreases in SME were also observed with increase in cellulose levels up to 8% and SiO 2 levels up to 4%. Moreover, decreases in both feed rate and SME could be observed a synergistic effect as 3% soybean oil co-added cellulose or SiO 2 . Added cellulose and SiO 2 increased water solubility index (WSI) of extrudates. Microstructure of cellulose and SiO 2 added extrudates showed a fine and friable texture of extrudate with thinner cell walls and more cell numbers. Increasing the levels of cellulose and SiO 2 could decrease moisture content (MC), cross-sectional expansion (CE), and specific volume (SV) but increase longitudinal expansion (LE) of extrudates. Shear force (SF) of extrudates increased with increase in cellulose and SiO 2 levels but all of them were lower than extrudate without any additive. The microstructure of 3% soybean oil co-added extrudates could not improve further but could be increase in WSI and CE as well as decrease in MC, LE, SV, and SF.

Using capacitance measurement and Mott-Schottky analysis, the semiconducting properties of passive films formed on chromium within the passive potential range under different conditions were investigated. The study reveals a p-type behavior of the passive layers. Two semiconductive parameters, i.e., the acceptor density (N-A) and the flatband potential (E-FB), which are mainly related to composition and surface charges of the passive films, have been measured. The effect of film formation potential, passivation time, pH and composition of solutions on the parameters are discussed. N-A increases either with lowering film formation potentials or with prolonging passivation times. This is attributed to the transformation of a less hydrated oxide film into a more hydrated form. The changes of E-FB are discussed as a function of adsorptive anions and pH values of electrolyte solution. (C) 2002 Elsevier Science Ltd. All rights reserved.

In situ scanning tunneling microscopy was employed to study the pretreatment method of Fe(110) surface and the adlayer structure of o-aminothiophenol (OATP) formed on it in 0.1 M NaClO4. A preparation method consisting of chemical etching and electrochemical annealing steps was primarily determined, which can consistently give atomically flat terraces on Fe(110) surface. This way of preparation could open up new perspectives for the investigations of surface structural properties on Fe that were normally not accessible because of easy oxidation and contamination outside ultrahigh vacuum. For the first time, the atomic resolution Fe(110) surface and the molecular resolution adlayer on it were imaged in solution. OATP molecules adsorbed on the Fe(110) surface and formed well-ordered p(2×2) structures with a coverage of 0.25.

Broadband circular and linear polarization conversions have been proposed in the paper by using thin birefringent reflective metasurfaces, which are composed of two orthogonal I-shaped structures placed on the top of a printed circuit broad with grounded plane on the bottom. We show that the metasurface manipulates the reflective phases of two orthogonal linearly-polarized waves independently by changing the dimensions of I-shaped structure. Hence, the polarization states of a linearly-polarized incident wave with normal incidence can be manipulated as desired after reflected by the anisotropic metasurface. Two polarization conversions have been presented by using such thin birefringent reflective metasurfaces: from linearly-polarized wave to circularly-polarized wave, and from linearly-polarized wave to cross-polarized wave. The metasurfaces work at microwave frequency, and the axial ratio better than 1dB is achieved within fractional bandwidth of 15% for circular polarization. Numerical and experiment results demonstrate good polarization conversions in a broad frequency band, which have excellent agreements with the theoretical calculations.

A high triplet energy (ET = 3.2 eV) electron transporting/hole blocking (ET/HB) material, 1,2,4,5-tetra(3-pyrid-3-yl-phenyl)benzene (TemPPB) with a super twisted structure and high thermal stability has been synthesized. An external quantum efficiency (EQE) of 19.6% was achieved by using TemPPB as the ET/HB material in a blue electrophosphorescent device, much higher than the EQE of 12.5% for the device using the conventional ET material, 3-(4-biphenyl)-4-phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole (TAZ). In addition, the weak ET property of TemPPB resulting from its super twisted structure can be enhanced via n-type doping with LiF. An EQE of 24.5% was achieved by combining n-type doping and a double-emission layer. This shows an alternative way to design ET/HB materials with high ET and improved thermal stability for blue electrophosphorescent devices.

Anodic oxygen evolution reaction on titanium oxide film and its affect on the surface and bulk properties of the film is an important subject in the Ti-based studies and applications. In this work, the behavior of oxygen evolution and some other related electrode processes occurring at anodically grown TiO 2 films on titanium were investigated within a relatively wide potential range by electrochemical measurements in 1 M perchloric acid solution. For the formation of the oxide film, three potential regions (two passive regions and the film breakdown region) were selected. The changes both in surface properties (mainly caused by oxygen evolution) and in bulk properties (mainly caused by increased potential) were taken into account for the observed different oxygen evolution behavior. The origin of a cathodic current peak at -0.2 V revealed in cyclic voltammograms was attributed to the reduction of the oxygen atoms adsorbed/absorbed at the oxide film surface, which were generated during anodic oxygen evolution. The flatband potential for the anodically formed titanium oxide films in 1.0 M HClO 4 was estimated as -0.2 V. With the semiconducting energy band structure models constructed for the Ti/oxide film/1 M HClO 4 electrode system, both the different behavior for anodic oxygen evolution on the titanium oxide films formed at different potentials and the electron transfer processes for the electrochemical reactions observed in this work were further interpreted.