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The continuous liquid interface production (CLIP) process has dramatically improved the fabrication speed of 3D printing technology, which makes it possible for Stereolithography to be used for direct manufacturing of functional parts. The effect of the CLIP process is significant owing to the skillful application of the photopolymerization inhibition effect of oxygen; therefore, the mass transfer behavior of the oxygen across the substrate is the key factor affecting the thickness and stability of the inhibition zone. In this paper, a low-cost scheme for a constrained substrate with good oxygen permeability that is made of PDMS membrane has been proposed, and the paper focuses on the effect of PDMS membrane and microscopic pore characteristics on the oxygen mass transfer behavior in the substrate. Based on the calculation result of the oxygen-diffusion coefficient in the PDMS membrane through molecular dynamics simulation, the influencing factors and laws of oxygen permeability of substrate are numerically studied using COMSOL software. The substrates with oxygen permeability that was measured based on the constructed experiment device were fabricated. The results show that the PDMS membrane possesses good oxygen content and the diffusion coefficient of the content in the PDMS film is 4.018 ×10−5 cm2/s. The thickness of the PDMS film and the area ratio and diameter of the micro-pores in the supporting glass substrate affect the oxygen permeability. Reducing the thickness of the PDMS film, increasing the pore-area ratio, and reducing the micro-pore diameter facilitate the oxygen permeability improvement under the premise of meeting the strength requirements. The research results can provide process improvement direction and theoretical basis for the preparation of constrained substrates.

In this study, an ultra-miniaturized low-profile angularly-stable frequency selective surface (FSS) based on 2.5-dimension convoluted interwoven element is designed. The dimension of FSS element is 0.014λ0 × 0.014λ0, where the λ0 represents the free-space wavelength of resonance frequency. The thickness is only 0.0015λ0. When the FSS is illuminated by electromagnetic wave, the frequency selective properties perform stable under different incident angles up to 85° for both TE and TM polarization. For better understanding, the operation mechanism, the design procedure, distribution of surface current, and equivalent circuit are presented. A prototype of proposed FSS is fabricated, the measurement results prove the validity of simulated ones. To further improve the performance, using the same design procedure, the size and thickness of designed FSS have been reduced to 0.0053λ0 × 0.0053λ0 and 0.00061λ0, respectively. Since the resonance frequency of proposed FSS is adjustable at any desired frequency, an ultra-miniaturized low-profile angularly-stable FSS for GSM 900 band has been designed. The designed FSS can be applied in GSM shielding effectively.

A triple band-notched ultra-wideband (UWB) monopole antenna etching novel folded resonator on the radiating patch, ground and between the feeding-line, is presented in this paper. The tri-rejection bands are 5.1–6.1 GHz, 7.6–8.8 GHz and 10.1–10.8 GHz which have covered bands of WLAN and ITU 8 GHz. To analyze the principle of proposed antenna, the simulation of parametric study and distribution of surface current are carried out. The size of antenna is 32 mm×19 mm×1 mm. And the test results are in good agreement with the simulation, which indicate that the antenna is promising for UWB system.

Based on 2.5-dimensional (2.5-D) structure, a novel compact dual-band frequency selective surface for GSM shielding is proposed in this letter. The unit cell geometry is designed by knitting double square-loop elements in 2.5-D which realizes the compact dual band-stop characteristics successfully. The size of proposed 2.5-D frequency selective surfaces (FSS) cell is only 0.072 λ0, where λ0 corresponds to free-space wavelength of the lower resonance frequency. The 2.5-D FSS is modeled and simulated by Microwave CST STUDIO SUITE. The simulation result shows that the FSS offers band-stop response at 900 and 1790 MHz with shielding effectiveness of 41.9 dB and 49.2 dB, respectively. Furthermore, the 2.5-D FSS performs a good angle-stability under both TE and TM polarizations. Hence, the designed 2.5-D FSS can be used for GSM shielding effectively. A prototype of proposed 2.5-D FSS is fabricated. The measurement result proves the satisfactory consistency with the simulation results.

Few burn dressings can self-regulate the optimal humidity levels that are required for wound healing, while also providing good anti-adhesive properties to prevent damage that can occur when wound dressings are changed. Consequently, a water-soluble carboxymethylcellulose sodium/sodium alginate/chitosan (CMC-Na/SA/CS) composite hydrogel has been developed as a potential burn wound dressing, with orthogonal testing revealing an optimal ratio of CMC-Na, SA, and CS as 2, 3, and 1 wt % for hydrogel preparation, respectively. The resultant hydrogel has been formulated into composite wound dressings that were then used for the treatment of deep second degree burn wounds in Sprague-Dawley (SD) rats. Analysis of the physical properties of this dressing revealed that it exhibits good water vapor permeability properties that promote the healing of deep second-degree burn wounds. The pro-healing mechanism of the dressing has been investigated Vascular endothelial growth factor (VEGF) expression was upregulated and basic fibroblast growth factor (bFGF) expression was downregulated in the early periods of wound healing, with upregulation of bFGF then occurring at a later stage of wound healing. At the same time, the wound dressing decreased the levels of tumor necrosis factor-α and interleukin-6, thus validating its beneficial effect on the wound healing process at a biomolecular level. In conclusion, this new hydrogel dressing was shown to exhibit excellent self-regulatory and anti-adhesive properties that synergistically promote the healing of burn wounds in rats, thus providing promising results that may have clinical applications. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 107B: 1471-1482, 2019.

Al2O3-SiCw (SiC whisker) powders were plasma sprayed on carbon steel under the electrostatic field. Effect of voltage on the microstructure and mechanical properties of the coatings was investigated. The erosion resistance was measured on the rotating disk erosion tester. The micro hardness and fracture toughness were obtained by the indentation method. It is found that the phase composition is unchanged for the coatings deposited in the presence or absence of electrostatic field while the grain size of coatings varies with the voltage. The porosity of coatings increases with the voltage slightly at first, and then a decrement tendency can be found. The erosion weight loss shows the similar trends with the porosity under the influence of voltage. The fracture toughness is the lowest when the voltage is 10 kV, and it is the highest for coatings deposited under no electrostatic field. The measurement of hardness yields the similar results though the voltage is different. The deflection behaviour of whiskers under the electrostatic field affects the deposition of molten powder and then the microstructure and properties of plasma sprayed coatings.

A novel single-layer dual-band miniaturized frequency selective surface (FSS) based on fractal structures is proposed and analyzed in this paper. A prototype with enough dimensions is fabricated and measured in anechoic chamber, and the measured results provide good agreement with the simulated. The simulations and measurements indicate that the dual-band FSS with bandstop selectivity center at 3.95 GHz and 7.10 GHz, and the whole dimension of the proposed FSS cell is only 7×7 mm2, amount to 0.092λ0×0.092λ0, that λ0 is free space wavelength at first resonant frequency. In addition, the center frequencies have scarcely any changes for different polarizations and incidences. What’s more, dual-band mechanism is analyzed clearly and it provides a new way to design novel miniaturized FSS structures.

A frequency selective surface (FSS) with polarization rotation which provides a quasi- elliptic bandpass response is presented in this paper. Based on substrate integrated waveguide cavity (SIWC), 90 degrees polarization rotation is obtained when electromagnetic wave passes through the frequency selective surface at specially appointed polarization in a range of 16.28-16.70 GHz. Moreover, TM120/TM210 dual-mode configuration appears in the cavity within the passband. The design has been proved with high stability to electromagnetic wave of different incident angles. And the measured results in anechoic chamber provide good agreement with those from commercial software simulations.

A wideband frequency selective surface (FSS) with a sharp band edge is proposed. The periodic cell includes a mushroom-like cavity and four L-type slots etched on the top and bottom conductor claddings of the cavity. The measured results show that the proposed FSS operates at X band with a 12.5% bandwidth (7.85-8.90 GHz), in which the insertion loss is less than 3 dB. Comparing with the FSSs based on substrate integrated waveguide cavity, the proposed FSS not only realizes high selectivity, but also realizes a 55.8% reduction in cell size.

The discovery of highly efficient photocatalysts for water splitting remains a challenge of high importance. Here, we report a series of novel organic conjugated polymers (OCPs) that contain complexed non‐noble metals for photocatalytic hydrogen evolution. The conjugated chromophore polymers were synthesized by a Heck coupling between ferrocene and phenantholine derivatives, which absorb broadly, even up to the near‐IR region. The photocatalyst performances were investigated for hydrogen evolution by using Fe3(CO)12 as a water reduction catalyst. H2 evolution rates up to 212.4 μmol h−1, with an apparent quantum yield of 10.3 % at 380 nm, were obtained with a photocatalyst polymer based on alternating ferrocene and 4,7‐bisphenyl‐1,10‐phenanthroline units. The high activity is likely due to favorable electron transfer and coordination of Fe3(CO)12 with phenanthroline in the supramolecular OCPs.

Ni doped amorphous mesoporous titaniasilica with Ti/Si mass ratio of 0.8 (NiTiO2SiO2) was synthesized, and this material was characterized by a combination of various physicochemical techniques, such as N2 physisorption, diffuse reflectance UVvis, X-ray diffraction, and FT-IR. Interestingly, and some of this material showed sphere shape.

Polycrystalline CdZnTe (CZT) films were grown by close-spaced sublimation method. The CdZnTe films were prepared on fluorine doped tin oxide (FTO) glass substrates at various argon (Ar) pressures from 200 Pa to 700 Pa. A comparative study of the films at different pressures was obtained by X-ray diffraction (XRD), scanning electron microscope (SEM) and Energy dispersive spectrometer (EDS) respectively. The XRD studies revealed that CdZnTe films had a preferential orientation along the (111) phase except the one at 500 pa. EDS analysis indicated that the increasing of Ar pressure decreased Zn content.

This study evaluated the feasibility of the mixed material as matrix of eco-toilet and the temporal change of pH value, T-N, T-P, T-K, organic matter and total reduction rate of dry weight in the compost. The mixed material of beanstalk and sawdust with a volume ratio of 1:1 can be used as reaction matrix of on-site composting-type eco-toilet to improve the microbial treatment of human feces. The human feces and urine could be composted to organic fertilizer rich in elements N, P and K. Change of pH in the toilet was divided two phases: changing phase (7.1-8.8) and stable phase (8.4-8.5). T-N, T-P and T-K contents increased with gradual input of feces and urine. Organic matter content decreased from 82.8% to 71.7% and the total reduction rate of dry weight increased gradually from 62.9% to 92.2%. Compost produced in the toilet could be used as organic fertilizer with the optimal concentration ratios for different plants.

A novel single-layer dual-band frequency selective surface (FSS) with miniaturized periodic element is proposed and analyzed. Using two symmetric patterns of metallic fractal lines printed on single layer, FSS centered at 4.05 GHz and 5.30 GHz is designed. The simulated results from CST Microwave Solver indicate that the whole dimension of the proposed FSS element is only 7×7mm2, amount to 0.094λ0 × 0.094λ0, where λ0 stands for free space wavelength at first resonant band. Besides, the center frequencies of two bands have scarcely any changes for different polarizations and incidences. The design of the FSS gets a well balance between miniaturization and dual-band. The measured results are in good agreement with the simulated.

The use of 5-guanosine monophosphate (GMP) with Sr(2+) ions to form G-quadruplex bundles as supramolecular templates for the preparation of hierarchical mesoporous silica nanotube materials is reported here, and some mesopores with a diameter of 4-22 nm were obtained. Furthermore, some mesopore channels which run perpendicularly to the center axis of the tube and penetrate right through the outer wall of the nanotubes were achieved by removing the templates. Besides, porous hollow silica spheres were obtained by changing some of the reaction conditions during the process of preparation. Their structures are stable even after high temperature calcination. A formation mechanism was proposed and discussed, and their structures were characterized using a number of means including X-ray diffraction, IR spectra, N2 adsorption-desorption isotherms, scanning electron microscopy (SEM) and transmission electron microscopy (TEM).

Hybrid photovoltaic concepts based on a nanoscale combination of organic and inorganic semiconductors are promising way to enhance the cost efficiency of solar cells through a better use of the solar spectrum, a higher ratio of interface-to-volume, and the flexible processability of polymers. In this work, two types of thin film solar cells have been developed. In both types of solar cells, poly-N-vinylcarbazole (PVK) is used as electron donor, cadmium sulfide (CdS) and titanium dioxide (TiO2) nanocrystals are used as electron acceptors, respectively. Since TiO2 has a wide band gap and can only absorb UV light, in the second type of solar cell, ruthenium dye is used as photo-sensitizer. The preliminary results of photoconductive and photovoltaic characteristics of these two inorganic-organic composites are presented.

After the invention of mesoporous material, the chiral mesoporous materials had been regarded as a hot research issue. Inspired by the chiral phenomenon, in this investigation, we presented several aspect of chiral mesoporous material from its first appearance, especially stated the template that could be used to prepare chiral mesoporous material, including chiral template and achiral template, besides, the different mechanisms and several distinguished scientists’ works were introduced, and some application of these material were introduced such as catalyst, HPLC stationary phases and many other fields.

CdS films were prepared by R.F. magnetron sputtering method. The effects of vapor CdCl2treatment on the properties of CdS films were studied. The vapor CdCl2thermal treatment at different temperature was employed in a CSS device, using CdCl2powder as evaporant. The structural and optical properties of CdS films were investigated by x-ray diffraction (XRD), PL spectra, and transmittance spectra, respectively. The results revealed that the CdS films had a structure of hexagonal wurtzite with a preferential orientation of the (002) plane. A better crystal quality and larger grain size, which are good for the solar cell application, were observed in the CdS samples annealed with CdCl2Subscript text.

Biofouling on underwater engineered structures, especially on ship hulls, results in increased operational and maintenance costs. Fouling is not only of an ecological interest, but it is also important from applied and commercial perspectives. With the development of society, widely used Tributyltin compounds (TBT) for biofouling control have been prohibited worldwide at the end of 2008. The need to develop new environment friendly antifouling agents has been highlighted. Herein we report on the synthesis and characterization of a novel cross-linkable copolymer containing a HMBA side chain. The paper is mainly focused on the synthesis of novel resin and its antifouling performance. Apart from use of acrylate monomer, the two other important monomers γ-methacryloxypropyltrimethoxysilane (HD-70) and N-(4-Hydroxy-3-Methoxy-Benzyl) acrylanine (HMBA) were selected to construct low surface energy materials. Finally, the antifouling properties of resins were carried through by the colonization of benthic diatoms (Nitzschia flosterium) and ocean plates of an offshore platform. Experimental results indicated the novel resins containing a HMBA side chain possessing better antifouling properties than a standard polydimethyl siloxane (PDMS) coating in the Qingdao ocean.

This study aims to investigate the changing of operational parameters and waste reducing rate, as well as the possibility of using produced composts as organic fertilizer in an on-site composting-type eco-toilet filled with mixed materials of beanstalk and sawdust as reaction matrix. During the 23-week period, change of pH was divided into three phases: acid phase (6.63-7.00), alkaline phase (9.00-9.71) and stable phase (8.10-9.00). With continuous input of feces and urine, total nitrogen, total phosphorus and total potassium contents was increased to reach 4.3%, 1.06% and 2.03%, respectively. Organic matter content decreased from 95.6% to 76.2% and the total reduction rate of dry weight increased gradually from 46.93% to 92.29%. The composts could be used as organic fertilizer at suitable concentrations. The suitable concentration for cucumber, cabbage and rape growth was obtained to be at compost ratios of 1:15-1:30, 1:15-1:20 and 1:25-1:40, respectively. Microbial utilization efficiency of human feces and urine could be improved when the mixed material of beanstalk and sawdust was used as reaction matrix in an on-sit composting-type eco-toilet. The mixed materials with beanstalk and sawdust at a volume ratio of 1:1 was found to be efficient to transform human feces and urine into organic fertilizer rich in the elements of N, P and K.

Giant magnetoresistance was found in DC magnetron sputtering Fe/ITO multilayers. The magnetic properties, electrical properties and magnetoresistance were investigated. A critical temperature is found around 50 K where the temperature dependence of resistivity and magnetoresistance ratio exhibit an abruptly change. The temperature dependence of resistance is found to obey Mott's 1/4 law for low temperature. The max magnetoresistance ratio of 2.0% and 6.7% is found at room temperature and 12.5 K, respectively. The increase of magnetoresistance ratio at low temperature is due to the decrease of spin-mixing effect.

Co–Al 2 O 3 granular films with a narrow distribution in cluster size of Co clusters embedded in Al 2 O 3 matrix were prepared by sequential deposition based on self-organized growth. Resistivity dependence of giant magnetoresistance (GMR) was studied. The GMR takes a maximum of 5.2% at room temperature and 9.4% at 13 K and 5700 Gs when the resistivity of the sample is 4×10 5 –7×10 5 μΩ cm. The temperature dependence of resistivities and GMR were discussed especially. A temperature dependence of conductance ρ∼ exp[ T 1 /( T + T 0 )] was found, which indicates the dominant conduction mechanism is fluctuation-induced tunneling. A linear relationship of GMR versus T was observed, GMR= a – kT , in applied magnetic field 5700 Gs. The remarkable character of temperature dependence of GMR should be due to the special microstructure that the clusters are monodispersed in the films.

Advancing the state-of-the-art 16nm technology reported last year, an enhanced 16nm CMOS technology featuring the second generation FinFET transistors and advanced Cu/low-k interconnect is presented. Core devices are re-optimized to provide additional 15% speed boost or 30% power reduction. Device overdrive capability is also extended by 70mV through reliability enhancement. Superior 128Mb High Density (HD) SRAM Vccmin capability of 450mV is achieved with variability reduction for the first time. Metal capacitance reduction by ∼9% is realized with advanced interconnect scheme to enable dynamic power saving.

A mutually pumped phase conjugator with a novel photorefractive crystal of copper-doped potassium sodium strontium barium niobate is reported, in which both incoherent beams are incident upon the negative c face and they travel in geometric paths similar to the outline of two arches. The maximum reflectivity attains 21%. The tolerance of the output to both incident angles and positions is assessed. No apparent cross talk is observed. A cross-readout mechanism is also used to explain phase-conjugate reflectivity production. It is verified that the configuration can be realized easily for a crystal with two longer a sides.

A mutually pumped phase conjugator is demonstrated with a novel photorefractive crystal of copper-doped potassium sodium strontium barium niobate, in which the beams travel in a geometric path similar to the outline of a sickle. The maximum reflectivity is up to 168%. Faster response times are measured and are also simulated as a function of incident beam power ratio. Four available input geometries are found. The phase conjugation signals exist wide range of angular and positional alignment. No apparent cross talk is observed. The faster build-up process of phase conjugation beams is tentatively explained.

Mesoporous Ce/SiO2/TiO2 sample with amourphous framework and micropherical-like structure were prepared via a solvothermal treatment employing mango peels as template, and the catalyst was characterized by a combination of various physicochemical techniques, such as N2 physisorption, diffuse reflectance UV–vis, X-ray diffraction and FT-IR. The photocatalytic activities of the samples were tested by the Photodegradation of dyes under solar light irradiation. The results of dye decomposition experiment indicate that the as-synthesized sample could efficiently degrade gentian(97%) and Rhdamine B(80%) under sun light.

A 32 nm gate-first high-k/metal-gate technology is demonstrated with the strongest performance reported to date to the best of our knowledge. Drive currents of 1340/940 muA/mum (n/p) are achieved at Ioff=100 nA/mum, Vdd=1 V, 30 nm physical gate length and 130 nm gate pitch. This technology also provides a high-Vt solution for high-performance low-power applications with its high drive currents of 1020/700 muA/mum (n/p) at total Ioff ~1 nA/mum @ Vdd = 1V. Low sub-threshold leakage was achieved while successfully containing Iboff and Igoff well below 1 nA/um. Ultra high density 0.15 um2 SRAM cell is fabricated by high NA 193 nm immersion lithography. Functional 2 Mb SRAM test-chip in 32 nm design rule has been demonstrated with a controllable manufacturing window.

With SnCl4·5H2O and graphene oxide as raw materials and aqueous solution of ethanol as the solvent, we have prepared SnO2 quantum dots (diameter about 3-5 nm)/graphene nanocomposites using a facile hydrothermal method in one step, and solved the reunion of quantum dots successfully. The visible-light-driven photocatalytic efficiency of SnO2 quantum dots depends to a great extent on their dispersity. Because of the large-sized two-dimensional surface, the graphene sheet could behave as a solid support for quantum dots through interfacial interaction to avoid particle aggregation. Composites of SnO2 quantum dot/graphene show a great photocatalytic performance in visible light, and the morphology and structure of the product are characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), Fourier transform infrared Spectrometer (FT-IR) and other techniques. The optical properties are investigated by using UV-visible (UV-vis) absorption spectrum. Additionally, the photocatalytic activity of the product is measured by the degradation of rhodamine-B dye solution in visible light. Results show that the preparation of samples with high catalytic activity in visible light, the shift in the optical response of composites may produce a positive effect on the improvement of photocatalytic efficiency in UV to visible spectral range Moreover, owing to its special π-conjugation structure, large specific surface area as well as high conductivity, graphene can enhance the photocatalytic activity. Compared with the pure SnO2, pure graphene catalytic performance is greatly improved in visible light, its excellent photocatalytic activity is due to the combination of strong absorption and effective separation of photogenerated carriers in the samples. Finally, the formation mechanism of the composite and its photocatalytic mechanism are studied.

Successful integration of high performance Cu dual damascene interconnects (DDIs) using a low-k etch stop (LES, oxygen-doped carbide, k/spl sim/3.0) and a porous low-k IMD (OSG, k/spl sim/2.5) has been demonstrated for the first time. The Cu DDIs with the LES not only revealed excellent resistance to stress induced voiding (SIV) but also exhibited 21% better interconnect RC delay, 100% higher via-EM endurance, 100 times lower line-line leakage at 125/spl deg/C, and 5% faster device operation speed as compared to the DDIs with a currently used etch stop (CES, oxygen-doped carbide, k/spl sim/4.5).

Eight level Cu/CVD low-k (k

Photo-physical properties of iridium complexes bis(1-(2',4'-difluorobiphenyl -4-yl)isoquinoline)iridium(III)(5-(4-(bis(4-methoxyphenyl)amino)phenyl)picolinic acid) used as phosphorescent dopant in polymer light-emitting devices with a blend ofpoly(9,9-dioctylfluorene) and 2-tert-butyl-phenyl-5-biphenyl-1,3,4-oxadiazole as a host matrix are investigated. The iridium complex exhibits distinct UV-vis absorption bands around 300–450 nm and intense red photoluminescent emissions peaked at around 618 nm in dichloromethane. The devices display a maximum external quantum efficiency of 4.8% and luminous efficiency of 3.1 cd·A−1 at current density of 3.2 mA·cm−2 with a dominant red emission peak around 620 nm and a shoulder around 660 nm. At 100 mA·cm−2, the devices still display a maximum external quantum efficiency as high as 3.9%.

The influence of phonon distribution on the frequency upconverted fluorescence emission is studied with laser spectroscopy in different matrices and at different ambient temperatures. The spectrum of phonon energy can be adjusted by varying the content of SiO2 in the oxyfluoride glass and glass ceramics, which affects the upconverted fluorescence emission of doped ions. Since the phonon energy depends on the sample temperature, the variation of the temperature can also influence the population rate of 3H4 level in Tm3+ doped low-phonon-energy LaF3 crystal, resulting in a change of the fluorescence upconversion.

By using MgO and MgF2 as high and low refractive index materials respectively and adapting metal-induced filter structures and transparent silicon gum as adhesive agent, 2200-2600 AA ultra-violet interference filters with good transmittance and stability.

The absorption spectra of Nd3+ in pure anhydrous neodymium chloride crystals and in anhydrous praseodymium chloride crystals (containing 0.1% NdCl3) have been examined systematically examined. The structures of the groups of their absorption lines are found to be similar to those of Nd3+ in NdCl3 crystals diluted by LaCl3 (containing 2% NaCl3 in LaCl3), except for a shift of the spectrum towards the long wave side. The shifts (relative to the ground state) of these corresponding sub-levels are proportional to the length of unit cell of the single crystals.