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The FBG sensors, embedded in triangle region of composite T-stiffened panels, were used to monitor the strain change during curing process and quasi-static compression real-timely. The results show that the compression load of stiffened panels with the FBG sensor embedded along the stiffener is the same as that without the FBG sensor. The FBG sensor embedded in the triangular area of the stiffened panels can effectively monitor during the curing process, and it can also be used to monitor the temperature and strain changes real-timely after curing process. In the quasi-static compression process, the strain curve measured by the FBG sensor is the same as the force-displacement curve. The FBG sensors can monitor accurately the damage such as lamination and cracking in the stiffened panels without affecting the property of the stiffened panels.

A full scale water-cooled Passive Residual Heat Removal System was designed and built for a 2 MW Molten Salt Reactor. In the process of heating the water tank, the heat transfer characteristics of the condenser in the system had an important impact on the temperature distribution and the development of thermal stratification in the water tank. Therefore, the heat transfer characteristics of the condenser at single-phase natural convection stage need to be experimentally researched and theoretically analyzed. Aiming at the condenser in the system, a series of experiments were carried out. Considering the influence of tube bundle effect on natural convection heat transfer, a set of theories using hydraulic diameter as characteristic length were put forward and applied to analyze the experimental results, which indicated the good agreement with the previous correlations consequently. This study can provide theoretical feasibility and experimental reference for the design of commercial molten salt reactor system in the future.

Fibrin- associated diffuse large B cell lymphoma (FA-DLBCL) is a rare entity, often incidental finding, categorized under “diffuse large B cell lymphoma associated with chronic inflammation (DLBCL-CI)“ in 2017 World Health Organization (WHO) classification of tumors of hematopoietic and lymphoid tissues. Here we report a 48-year-old male with FA-DLBCL who experienced recurrence within one year from initial presentation. The patient had a history of an abdominal aortic aneurism and underwent an endovascular aneurysm repair (EVAR) in 2013. Later in 2019, he was found by CT aortogram to have endoleak of the aneurysm repair. He underwent an open abdominal aortic aneurysm repair with explant of the endovascular stent. The explanted graft was sent to pathology and was found on gross examination to have ample adherent tissue. On microscopic examination this tissue was composed of abundant fibrinous material with several foci of large pleomorphic lymphocytes with enlarged round to polyhedral nuclei, prominent nucleoli, open chromatin, and scanty cytoplasm. Necrosis was also seen in a largest focus of tumor infiltrate. By immunohistochemistry, the atypical, large lymphocytes expressed CD20 and MUM-1; and positive for EBV, by Epstein-Barr virus (EBV) in situ hybridization (EBER-ISH). Together, the diagnosis for FA-DLBCL was made. Further work up by PET scan showed no active disease. The patient re-presented 10 months later with right lower extremity ischemia due to the vascular graft thrombosis. The thrombectomy specimen showed identical findings of his initial FA- DLBCL. Here we discuss the clinicopathologic findings of this entity and the importance of clinical follow up.

A new mineral species of the pyrochlore supergroup, oxynatromicrolite (IMA2013-063), (Na,Ca,U)2Ta2O6O, was found in the No. 309 rare-metal granitic pegmatite vein, Guanpo, Lushi county, Henan Province, China, which is characterized by tantalum at theB site and oxygen at the Y site and is Na dominant at the A site. The mineral occurs as strongly metamict, and mostly euhedral octahedral crystals up to 0.05–0.20 mm across. The measured density of an unheated sample is 6.580(4) g cm–3, and the calculatedone is 6.506 g cm–3. Optically, the mineral is isotropic, with an index of refraction 1.999(5) and a reflectance of 11.88% (470 nm). When heated to 1000°C for 4 hours in N2, the mineral recrystallizes in the cubic system, with space group Fd3mand with unit-cell parameters similar those of other pyrochlore supergroup species: a = 10.420(6) Å, V = 1131.4(2) Å3. Electron microprobe analyses revealed the following composition of the mineral (in wt.%): Na2O 5.41, CaO 4.56, UO214.60, La2O3 0.16, Ce2O3 0.11, Nd2O3 0.13, PbO 0.62, Ta2O5 61.52, Nb2O5 8.21, Sb2O5 0.23, TiO2 0.05, SiO2 0.56, SnO2 0.29, F1.04, H2O 1.50 (calculated to correspond to 0.47 H2O pfu), F≡O –0.44, sum = 98.53%, which corresponds to the empirical formula (Na0.99Ca0.46U0.31Pb0.02La0.01H2O0.21)∑2.00(Ta1.58Nb0.35Si0.05Sn0.01Sb0.01)∑2.00O6 (O0.43F0.31H2O0.26)∑1.00, represented by the simplified formula (Na,Ca,U)2(Ta,Nb)2O6(O,F).Oxynatromicrolite crystallized during the late-stage of formation for the No. 309 pegmatite dyke and is associated with quartz, albite, potassium feldspar, muscovite, kaolinite, tantalite-Mn, stibiotantalite, pollucite, spodumene, montebrasite, Hf-rich zircon, a red tourmaline, polylithionite,trilithionite, luanshiweiite-2M1 (IMA2011-102) and a hydrated derivative of oxynatromicrolite.

Using persistent experiment method, combined with Gleeble,hardness analysis, SEM, EDS, TEM and other analytical methods, the hot deformation, stress rupture and precipitation behavior of TP310HCbN heat resistance steel was analysed at 650℃ and 700℃, the results show that:the change of the hardness is not obviously under two different stress rupture temperature; with stress rupture time prolongs, TP310HCbN heat-resistant steel intragranular precipitates from granular into rod-shaped, and presence of wormlike NbCrN rich precipitates and dislocation interactions; Taiyuan Iron and Steel production of TP310HCbN heat-resistant steel at 650/700℃-100000h extrapolation lasting strength meet the standard requirements.

We propose and experimentally demonstrate a frequency reconfigurable antenna using ferrite loaded half-mode substrate integrated waveguide (SIW). The antenna design is based on a SIW cavity with an embedded ferrite slab, which causes the resonant frequency of the cavity tunable under bias magnetic field. The antenna features omni-direction radiation and small size. A prototype antenna is designed and fabricated. The measurements show the tunable frequency bandwidth is over 11% covering frequencies 5.04–5.62 GHz in low bias magnetic field region, and 5% covering 4.28–4.5 GHz in high bias magnetic field region. The measurement is in good agreement with simulations. The gain of antenna is all over 1.6 dBi, and the frequency reconfiguration does not affect the radiation pattern of the antenna, providing a preferable feature for frequency reconfigurable antenna. This type of antenna may be a good candidate for practical applications such as base stations and satellites. © 2017 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:1365–1371, 2017

We prepare the sandwich-like carbon nanotubes/carbon nanoparticles film/vertically aligned carbon nanotubes on silicon substrate (CNTs/CNPs/VACNTs/silicon) by pyrolysis of FePC at 880 °C. The field emission properties of the CNTs/CNPs/VACNTs/silicon are investigated. The lower turn-on electric field of 0.78 V / μ m at a current density of 20 μ A / c m 2 , lower threshold electric field of 1 V / μ m at a current density of 1 m A / c m 2 and good emission current stability are observed. The unique structure not only provides large field enhancement factor but also strongly reduces the field-screening effect. The above results make CNTs/CNPs/VACNTs/silicon an effective field emitter.

Split-ring resonator (SRR) has a narrow absorption response to the incident waves. To broaden the absorption bandwidth, we designed a 3-D structure to place the SRRs of different sizes vertically as a pyramids so that they can resonance in different frequency. Further, we strengthen the absorption effect by loading resistors in the SRRs. The influences of the SRRs' size and coupling effects between SRRs are discussed. So designed low-frequency absorber features broadband absorption, lower profile and small size. The −10dB bandwidth cover frequency range of 1.8–3.7GHz at relative bandwidth 69%. At the highest working frequency of the absorption bandwidth, the electric thickness is less than 0.3 and side length of the unit cell less than 0.25.

We present a novel absorber based on a periodic array of parallel-plate waveguide. With the assistance of a layer of lumped circuit that consists resistors, capacitors on top the parallel-plate waveguide, the absorber designed working at microwave L, and S band performs high absorption in a broadband frequency range. The reflectivity of −10dB covers the frequencies 1.4–5.5 GHz with relative absorption bandwidth about 120% in single polarization mode. An equivalent circuit model is proposed to analyze the broadband absorption performance and to be used for a parametric analysis. Further, the absorber is designed working in dual polarization modes for which the absorption bandwidth covers 1.9–4.7 GHz. The absorber features lower profile with thickness of 1/10 of the wavelength at the lowest operating frequency.

Phase unwrapping (PU) is a difficult task commonly found in applications involving interferometric synthetic aperture radar (InSAR), magnetic resonance imaging (MRI) and optical surface profile measurements; all of which involve mathematically ill-posed problems. Conventional algorithms exhibit strong shortcomings in PU when phase discontinuity flaws exist. To simulate these situations, we are custom-designed test data with a phase discontinuity flaw. This simulated data is a 3D Gaussian distribution with an arc-shaped notch as a phase flaw. PU is carried out by Bayesian inference and MRF (Markov Random Field) modeling. A graph cut algorithm is employed for optimization with respect to energy minimization. Three other conventional algorithms are also employed and their PU performance is compared. The results show the good performance and effectiveness of the Bayesian MRF modeling method. These experimental results are important references for phase unwrapping problems when phase discontinuities exist.

Notice of Violation of IEEE Publication Principles "A Thin Broadband Microwave Absorber with Hexagonal Resistive Frequency Selective Surface" by Feifei Li, Chao Meng, Fan-guang Meng, Digang Fan, Ping Chen, and Rui-xin Wu in the IEEE Antennas and Wireless Propagation Letters (Early Access) April 2018 After careful and considered review of the content and authorship of this paper by a duly constituted expert committee, this paper has been found to be in violation of IEEE’s Publication Principles. This paper contains significant portions of work presented in the paper cited below. The original work was translated and copied without attribution (including appropriate references to the original author(s) and/or paper title) and without permission. "Design of a Wide‐band Metamaterial Absorber Based on Resistance Films" by Gu Chao, Qu Shao‐Bo, Pei Zhi‐Bin, Xu Zhuo, Lin Bao‐Qin, Zhou Hang, Bai Pen, Gu Wei, Peng Wei‐Dong, and Ma Hua in Acta Physica Sinica, Vol 60, No. 8, August 2011 We realized a thin, broadband absorber based on resistive frequency selective surface (FSS). By introducing a design parameter, p-factor, we successfully designed a microwave absorber, whose reflectivity below -10dB covers 6.4-24.9 GHz. The thickness of the absorber is only 0.087-L at the lowest operating frequency. We show that broadband absorption can be achieved by carefully balancing susceptances of resistive FSS and other parts of the absorber. Furthermore, we find that lossless dielectric slabs with lower dielectric constant are the best choices for broadband absorber. Experimentally, the samples were fabricated by using silk-screen printing technique and their absorbing performance was measured. Experimental results are in good agreement with simulated ones. Our work provides a method to realize broadband absorber in a simple way, which may be used for the absorbers working in THz, infrared or even optical band.

The morphology of nanoporous Si pillar arrays (Si-NPA) prepared by hydrothermal etching was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high-resolution TEM (HRTEM). The results reveal that Si-NPA has a silicon micro/nanometer composite structure, which makes it an ideal template. Si-NPA-based Cu nanocomposite systems (Cu/Si-NPA) were obtained by immersing Si-NPA in 0.01 M CuCl2 for 1, 5, 10 or 30 min at room temperature. Time-dependent morphological changes and the elemental composition of Cu/Si-NPA were analyzed by SEM, X-ray diffraction (XRD) and X-ray energy-dispersive spectroscopy (EDS). The number and the average size of Cu nanoparticles increased with the immersion time. Besides, Cu/Si-NPA inherited the morphological characteristics of Si-NPA. The results indicate that the morphological evolution of Cu/Si-NPA can be explained by the existence of microscopic electrochemical cells.

Copper/silicon nanocomposite system (Cu/Si-NPA) is prepared by immersion plating Cu nanoparticles on silicon nanoporous pillar array (Si-NPA). The Cu/Si-NPA samples are heated under nitrogen for 2 h at elevated temperatures of 400 °C, 600 °C, and 800 °C. The morphological changes of Cu nanoparticles before and after heat treatments are characterized by SEM. The crystallinity and the average size of Cu nanoparticles before and after heat treatments are studied by XRD. The results show that two possible mechanisms, Ostwald ripening, and particle migration and coalescence, are believed to be responsible for the ripening of annealed Cu nanoparticles at different annealing temperatures.

Three kinds of electron-blocking layer(EBL) AlGaN based LED were compared numerically.They are conventional AlGaN EBL,AlGaN-GaN-AlGaN(AGA) and gradual Al composition AlGaN-GaN-AlGaN(GAGA) EBL.Their porfermance were analyzed involved carrier concentration in the active region,energy band diagram,electrostatic field and internal quantum efficiency(IQE).The results indicate that the LED with an GAGA EBL exhibits a better hole injection efficiency,a more peaceable efficiency droop,a lower electron leakage,and a smaller electrostatic field than the LED with a conventional AlGaN EBL or with an AGA EBL.

On cathode glass faceplate the new integral type cold cathode was developed.The printed silver slurry was sintered to form the silver bottom electrode.The thin-layer bottom electrode paste including a great deal of carbon nanotube was prepared,and was screen-printed on the silver bottom electrode surface.The ordinary carbon nanotube paste was fabricated on the baked thin-layer bottom electrode paste.The two types of pastes were simultaneous sintered in the sintering furnace with the protection of high purity argon atmosphere.The sintered thin-layer bottom electrode would combine with the silver bottom electrode,which the carbon nanotube layer was covered on its surface.In one cathode pixel there were two carbon nanotube field emitters.Due to the spare carbon nanotube field emitter,the service life of field emission display could be prolonged greatly.Using thin-layer bottom electrode as interface layer between the silver bottom electrode and the carbon nanotube layer,the adhesion property of carbon nanotube was improved and the reliable ohmic contact had also been confirmed.With carbon nanotube as cathode material,the integral type cold cathode field emission display was fabricated,which exhibited good luminescence image quality and better field emission characteristics.Comparing with the ordinary carbon nanotube cathode field emission display,the turn-on electric-field could be reduced from 2.11 V/μm to 1.68 V/μm,the maximum field emission current could be enhanced from 905.7 μA to 1 866.2 μA,and the field emission current fluctuation at 367 μA would not exceed 4.5%.The integral type cold cathode field emission display has subsequently been operated for more than 10 days with stable luminance brightness.

With screen-printing technique,a novel carbon nanotube(CNT) cathode preparation method was developed.Using double-walled CNT as primary material,the mixing CNT paste was fabricated,in which the minute Ag particles were included.On the mixing CNT paste printed on the conducting electrode surface,the common CNT paste was prepared.The baked CNT pastes were sintered simultaneously in the chain sintering furnace to remove the organic solvent,and the second-printing type CNT cathode was formed after the proper overvoltage post-treatment process was conducted.With the fabricated second-printing type CNT cathode,the field emission characteristics could be improved significantly.The triode second-printing CNT cathode field emission display was fabricated,which exhibited higher luminous brightness and better luminescence image brightness uniformity.Comparing with the common CNT cathode field emission display,the turn-on electric field could be reduced from 2.15 V/μm to 1.75 V/μm and the maximum field emission current would be enhanced from 735.8 μA to 1 588.5 μA.The developed preparation method of CNT cathode possessed considerable potential for practical applications and the fabrication cost was low.

Rear packaging face-plate was fabricated with the cut soda lime flat panel glass.With high effective screen-printing technique,the semicircle-group cathode-grid structure was developed on the rear packaging face-plate surface.The sintered silver slurry layer was used to form the double long-bar electrodes of the conducting electrode group in the semicircle-group cathode-grid structure,and the insulation layer was fabricated using the solidified insulation slurry.On the long-bar electrodes surface,the carbon nanotube cathodes with double semicircle shape were prepared,which was used to emit lots of electrons.The grid was fixed on carbon nanotube cathode of the rear packaging face-plate,and the grid substrate was adopted to separate the grid and the cathode.From the measure results,with the fabricated semicircle-group cathode-grid structure,the capacity effect between the cathode and the grid would be further reduced,the electron emission ability of carbon nanotube cathode could be improved,and the operation flexibility of whole field emission display prototype was also enhanced.Using carbon nanotube as cathode material,the triode structure small-sized field emission display prototype was fabricated,which possessed good field emission characteristics,high luminescence brightness and better luminescence image uniformity.The turn-on electric-field of fabricated triode field emission display prototype was approximate 2.12 V/μm,and the total fabrication cost was low.

Diamond film and diamond /Ti film were synthesized by microwave plasma chemical vapor deposition (MWPCVD) method on Si (100). Comparative studies on field emission properties of diamond and diamond /Ti films.The results show that diamond /Ti film has demonstrated large emission currents at much lower threshold voltages. Field emission current density increases rapidly with the increase of electric field and reaches to 1400μA/cm2 at 25 V/μm.

The conducting chains in printed CNT film were considered as (MI)iV or (MI)i-1MV configuration. The transport and field emission of electrons in printed CNT film can be considered as tunneling conduction. The transmission coefficient of an insulator barrier surrounding a CNT was calculated via quantum mechanical principle. When an electric field is applied to CNTs, the barrier of residual was considered as a group of rectangular potential barriers. The total transmission coefficient for a residual-covered emitter during emitting was solved numerically from the product of the two transmission coefficient for the potential barriers of residual and the vacuum level.

High density、uniform particles diamond films were synthesized by microwave plasma chemical vapor deposition (MWPCVD) method on Si (100). In order to improve field emission properties of thin films, sputtering the metal Ti、Al、Mo、Ni on the diamond surface respectively，and compared the kinds of diamond/metal composite film of field emission performance. The results show that the field emission properties of diamond / metal Ti composite thin film are better. The possible mechanism will be discussed in this study.

We have reanalyzed reaction cross sections of 16N on 12C target. The nucleon density distribution of 16N, especially surface density distribution, was extracted using the modified Glauber model. On the basis of dilute surface densities, the discussion of 15N(n, ��)16N reaction was performed within the framework of the direct capture reaction mechanism. The calculations agreed quite well with the experimental data., 5 pages, 3 figures. arXiv admin note: text overlap with arXiv:0810.3867 by other authors

A novel energetic cuprous azide complex with the formula of [Cu2(dmpyz)(N3)2] n (1) (dmpyz: 2,5-dimethylpyrazine) has been synthesized through hydrothermal method by utilizing the reducibility of H3PO3 and structurally characterized by X-ray single crystal diffraction method. Single crystal X-ray diffraction analysis reveals complex (1) featuring a two-dimensional layer structure constructed from copper(I) atoms bridged by azide anion and further connected by pyrazine ligand to form a 3D network. The result of catalysis research reveals it can promote the burning rate of main component of rocket propellants.

An energetic cuprous azide complex, [Cu2(2apyz)(N3)2] n (1) (2apyz = 2-aminopyrazine), has been synthesized through hydrothermal method by utilizing the reducibility of H3PO3 and structurally characterized by single-crystal X-ray diffraction. Complex 1 has a 2-D layer structure constructed from copper(I) bridged by azide and pyrazine. Catalysis research shows 1 can promote the burning rate of the main component of rocket propellant.

A coordination polymer, [Co(2-mpac)2(4,4′-bpy)·(4,4′-bpy)] n (2-mpac: 5-methyl-2-pyrazinecarboxylic acid; 4,4′-bpy: 4,4′-bipyridine), has been synthesized through hydrothermal synthesis and structurally characterized by X-ray single crystal diffraction. Single crystal X-ray diffraction analysis reveals a 3-D network featuring a 1-D tunnel filled with 4,4′-bpy molecules. Elemental analysis, IR, thermogravimetric analysis, and magnetic properties are presented.

In order to realize preferable white light-emitting diodes with high color rendering index and optimized luminous efficiency,white InGaN/GaN multi-quantum-well dual-wavelength light-emitting diodes(LEDs) were grown on(0001)-oriented sapphire substrates by metal-organic chemical vapor deposition(MOCVD).Photoluminescence and electroluminescence properties of dual-wavelength LEDs with different In content were also studied.The experimental results indicated that In component plays a critical role on stability for electroluminescence spectrum and luminous efficiency of the dual-wavelength LED structures.In addition,YAG∶Ce phosphor-converted white light emission with high color rendering index was achieved using dual-blue emitting active regions.

The measurement of parity-violating (PV) observables in few-nucleon system can shed light on our current understanding of the weak interaction between nucleons. Theoretical models describe the nucleon-nucleon weak interaction at low energies use a series of undetermined parameters. Two parity violating measurements have been considered: the capture of polarized slow neutrons on hydrogen ( + p ? d + ?) at Los Alamos National Laboratory for first phase and Oka Ridge National Laboratory for second phase and the helicity dependence of the deuteron photodisintegration cross section using circularly polarized photons ( + d ? n + p) at Shanghai Institute of Applied Physics. The goal of both experiments is to constraint the weak meson-nucleon couplings to a precision of 1 ? 10?8. The introduction of both experiments is presented.

We theoretically and experimentally studied a transmitting-absorbing material that had transmission window within the absorption band. The material had a sandwich structure comprised of a resistive metasurface, a dielectric substrate and a metallic slot frequency-selective surface (FSS). The material showed lower reflectivity in a wide frequency range; the -10 dB absorbing bandwidth could be over 76% (64% in experiments). Meanwhile in the middle of the range the transmittance up to -1.7 dB was observed at about 10 GHz where slot FSS had good transparency. We showed the lower reflectivity of our material was mainly due to the absorption of incident radiation energy except for the transparent window where the radiation energy passed through the materials. The transmitting window could be adjusted by changing the geometry parameters of slot FSS. Our material had the advantages of thin thickness, small size of unit cell, convenient fabrication and easy to extend to other frequency bands. This kind of transmitting-absorbing material provided a new way for the applications, such as light harvesting, sensing and radome materials.

Utilizing Co(2-mpac)2(H2O)2 as molecular building block, a coordination polymer, [Co2(2-mpac)4(4,4′-bpy) · 2H2O] n (1) (2-mpac = 5-methyl-2-pyrazinecarboxylic acid; 4,4′-bpy = 4,4′-bipyridine), was synthesized and structurally characterized by X-ray single crystal diffraction. Elemental analysis, infrared, and magnetism are presented. Variable temperature magnetic susceptibility measurements exhibit weak antiferromagnetic interaction between Co centers in 1.

The astrophysical reaction rate of 12C(?, ?)16O plays a key role in massive star evolution. However, this reaction rate and its uncertainties have not been well determined yet, especially at T9 = 0.2. The existing results even disagree with each other to a certain extent. In this paper, the E1, E2 and total (E1+E2) 12C(?, ?)16O reaction rates are calculated in the temperature range from T9 = 0.3 to 2 according to all the available cross section data. A new analytic expression of the 12C(?, ?)16O reaction rate is brought forward based on the reaction mechanism. In this expression, each part embodies the underlying physics of the reaction. Unlike previous works, some physical parameters are chosen from experimental results directly, instead of all the parameters obtained from fitting. These parameters in the new expression, with their 3? fit errors, are obtained from fit to our calculated reaction rate from T9 = 0.3 to 2. Using the fit results, the analytic expression of 12C(?, ?)16O reaction rate is extrapolated down to T9 = 0.05 based on the underlying physics. The 12C(?, ?)16O reaction rate at T9 = 0.2 is (8.78 ? 1.52) ? 1015 cm's?1 mol?1. Some comparisons and discussions about our new 12C(?, ?)16O reaction rate are presented, and the contributions of the reaction rate correspond to the different part of reaction mechanism are given. The agreements of the reaction rate below T9 = 2 between our results and previous works indicate that our results are reliable, and they could be included in the astrophysical reaction rate network. Furthermore, we believe our method to investigate the 12C(?, ?)16O reaction rate is reasonable, and this method can also be employed to study the reaction rate of other astrophysical reactions. Finally, a new constraint of the supernovae production factor of some isotopes are illustrated according to our 12C(?, ?)16O reaction rates.

The influence of Si doping on the photoluminescence (PL) properties of (Al"0"."3Ga"0"."7)"0"."5In"0"."5P/Ga"0"."5In"0"."5P multiple-quantum-wells (MQWs) was studied. For the samples without p-type layers, the PL peak wavelength from (Al"0"."3Ga"0"."7)"0"."5In"0"."5P/Ga"0"."5In"0"."5P MQWs did not vary when Si was doped in MQWs, the PL peak intensity did not change obviously and the PL FWHM broadened. We consider that Si doping results in worse interface quality of (Al"0"."3Ga"0"."7)"0"."5In"0"."5P/Ga"0"."5In"0"."5P MQWs. However, for the full light-emitting diode (LED) structure samples, the PL intensity of MQWs obviously increased when Si was doped in MQWs. The PL intensity from MQWs with Si-doped barriers was about 13 times stronger than that of undoped MQWs. The PL intensity from MQWs with Si-doped barriers and wells was strong as 28 times as that of undoped MQWs. The reasons are discussed.

Four kinds of different post-treatment methods or conditions, including low residue adhesive tape treatment, high residue adhesive tape treatment, plasma exposure treatment and mechanical crushing and blowing treatment, were applied to screen-printed carbon nanotube (CNT) films to improve their field emission ability. The effects and results of these methods or conditions on field emission characteristics of printed CNT films were compared in some aspects such as I-V curves, luminescent images and annealing treatment and so on.

The carbon nanotubes (CNTs) film was fabricated successfully on 5 cm × 5 cm borosilicate glass substrate by using capacitive coupled radio frequency plasma-enhanced infrared thermal chemical vapor deposition equipment (CC-RF-PE-IT-CVD). The substrate temperature was 580 °C. Inborn Fe(OH) 3 sol was used as catalyst during the growth. Observation by scanning electron microscope indicated CNTs nearly uniformly distributed on the substrate. The measurement results of field emission characteristics at three stochastic-selective zones indicated that the turn-on field of electron emission for the sample was around 2.1 V μm −1 , and emission current density was larger than 400 μA cm −2 at 6 V μm −1 . Similar effective work function and field enhancement factor for the three different zones exhibited that the sample possesses good emission uniformity. Therefore, the cathode is suitable for FEDs.

Pure cubic phase barium titanate nanoparticles with an average diameter of about 20 nm have been synthesized via a one-step sol-precipitation route at water bath (about 80 °C) for 5 h without surfactant and any post-treatment. Based on the observation of transmission electron microscopy and high-resolution electron microscopy images, the as-synthesized BaTiO3 nanoparticles exhibit the nature of single-crystal and agglomerate-free. The formation of the single-crystal BaTiO3 nanoparticles resulted from a diffusion mechanism of Ba2+ ions into the gel at strong alkaline condition.

Fabricated artificial opal templates and low pressure metal-organic chemical-vapor deposition have been used to infill the voids within opals and optimized the growth parameters. Scanning electron microscopy images, X-ray diffraction and reflection spectra results show that the InP is homogeneously distributed inside the opals, with high crystalline quality. The filling ratios of InP in the voids is about 12.8% and the photonic band gap is shifted to higher wavelength as a result of the high contrast of dielectric constants when InP is introduced which are in agreement with theoretical calculations.

Co-passivated porous silicon (CPS) was prepared by stain etching. CPS samples prepared at different etching stages have different morphologies. All these morphologies are significantly different from those of conventional porous silicon (PS) etched in none cobalt-etching solution. The experimental results indicate that Co atoms only exist in a very thin layer on CPS surface, where Co atoms are well-distributed and Co atoms have hardly diffused into the substrate. Compared with the formation mechanism of conventional PS, there are two routes to generate holes in the formation of CPS, and there is NO 2 gas evolved from etching solution in a certain condition during the etching.

AlGaInP/GaInP multiple quantum well structures were grown by low-pressure MOCVD on n-GaAs substrates. The influence of Si-doping to the characteristics of AlGaInP/GaInP multiple quantum wells was studied. The PL intensity from MQW with Si-doped barriers is about 13 times stronger than that of undoped MQW. The PL intensity from MQW with Si-doped barriers and wells is strong as 28 times as that of undoped MQW.