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In order to solve the problem of thermal conductivity test of large-size diamond, the ϕ100 mm sample holder of vertical mode and In-Plane mode was designed for the NETZSCH LFA467 HyperFlash instrument. The test results of the ϕ100 mm sample holder are proved to be credible from both principle and test results. From the theoretical analysis, it is concluded that the change of sample boundary conditions brought by the new sample holder has little effect on the test results. The thermal conductivity test results of the ϕ100 mm sample holder in the In-Plane mode are 6. 5% higher than that of the standard sample holder, and the thermal conductivity test results of the ϕ100 mm sample holder in the vertical mode are 3. 6% higher than that of the standard sample holder. The test results are still within the acceptable range. The ϕ100 mm sample holder designed in this paper can test ϕ100 mm samples at most, which helps to protect the integrity of samples. In this paper, the non-destructive testing of thermal conductivity of large-size diamond by laser flash method is realized. [ABSTRACT FROM AUTHOR]

Interplay between the outer steel tubes and the core concrete provides an important guarantee for the superior performance of concrete-filled steel tube (CFST) columns compared to that of reinforced concrete columns. In order to optimize the construction of the large-size non-studded CFST columns in an on-going practical project, the strain distributions in the column under construction were measured and tracked, and the law of the strain distributions of the column under construction is revealed. The study finds that the plane section assumption was not applicable to the strain distributions of the column. Nonlinear variations in the strain levels were observed under bi-directional bending of the column. The absence of studs inside the steel tube significantly weakened the interplay of the outer steel tube and the core concrete by means of a significant slip between the concrete and the steel tube at the column corners. The concrete and the steel tube tended to be stressed and deformed independently. Practical suggestions are given for the design and construction of this type of column. The study results are expected to lay a basic and valuable foundation for in-depth investigations on the mechanical behavior of large-size non-studded concrete-filled steel tube columns under construction. [ABSTRACT FROM AUTHOR]

Interplay between the outer steel tubes and the core concrete provides an important guarantee for the superior performance of concrete-filled steel tube (CFST) columns compared to that of reinforced concrete columns. In order to optimize the construction of the large-size non-studded CFST columns in an on-going practical project, the strain distributions in the column under construction were measured and tracked, and the law of the strain distributions of the column under construction is revealed. The study finds that the plane section assumption was not applicable to the strain distributions of the column. Nonlinear variations in the strain levels were observed under bi-directional bending of the column. The absence of studs inside the steel tube significantly weakened the interplay of the outer steel tube and the core concrete by means of a significant slip between the concrete and the steel tube at the column corners. The concrete and the steel tube tended to be stressed and deformed independently. Practical suggestions are given for the design and construction of this type of column. The study results are expected to lay a basic and valuable foundation for in-depth investigations on the mechanical behavior of large-size non-studded concrete-filled steel tube columns under construction.

The intramuscular subtype of nodular fasciitis (NF) is rare with lesions normally not more than 2 cm in size and characterized by pseudosarcomatous morphology. We report a case of a 27-year-old man with a large-size intramuscular NF. The patient came for treatment complaining of an increasingly enlarged mass in the left upper arm for 4 months. Magnetic resonance imaging (MRI) confirmed the presence of a well-defined tumor measuring 5 cm within the outer edge of the middle humerus. Microscopically, the neoplasm was rich in fibroblasts and myofibroblasts in an interlaced pattern with high mitotic index and evident multinuclear giant cells. Erythrocyte extravasation was easily seen in the stroma. The tumor border was infiltrative. Immunohistochemically, the tumor cells were positive for smooth muscle actin (SMA) and negative for cytokeratin, desmin, H-Caldesmon, CD34, S100, ALK, and β-catenin. Fibrosarcoma was highly suspected by histopathological and immunohistochemical examination. Molecular detection demonstrated evidence of ubiquitin-specific peptidase 6 (USP6) gene rearrangement in this tumor. Based on the findings, the tumor was diagnosed as intramuscular NF. At 56 months after the initial surgery, the patient had recovered with no evidence of recurrence or metastasis. Large-size intramuscular NF is very rare and easily overdiagnosed as malignant tumor due to its obvious pseudosarcomatoid pathological features. USP6 gene rearrangement detection can effectively avoid this major misdiagnosis.

Abstract In past decades, Ni-based catalytic materials and electrodes have been intensively explored as low-cost hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) catalysts for water splitting. With increasing demands for Ni worldwide, simplifying the fabrication process, increasing Ni recycling, and reducing waste are tangible sustainability goals. Here, binder-free, heteroatom-free, and recyclable Ni-based bifunctional catalytic electrodes were fabricated via a one-step quick electrodeposition method. Typically, active Ni nanodot (NiND) clusters are electrodeposited on Ni foam (NF) in Ni(NO3)2 acetonitrile solution. After drying in air, NiO/NiND composites are obtained, leading to a binder-free and heteroatom-free NiO/NiNDs@NF catalytic electrode. The electrode shows high efficiency and long-term stability for catalyzing hydrogen and oxygen evolution reactions at low overpotentials (10 η HER = 119 mV and 50 η OER = 360 mV) and can promote water catalysis at 1.70 V@10 mA cm−2. More importantly, the recovery of raw materials (NF and Ni(NO3)2) is quite easy because of the solubility of NiO/NiNDs composites in acid solution for recycling the electrodes. Additionally, a large-sized (S ~ 70 cm2) NiO/NiNDs@NF catalytic electrode with high durability has also been constructed. This method provides a simple and fast technology to construct high-performance, low-cost, and environmentally friendly Ni-based bifunctional electrocatalytic electrodes for water splitting.

Large-size, organic light-emitting device (OLED) panels based on highly reliable gate driver circuits integrated using InGaZnO thin-film transistors (TFTs) were fabricated to achieve ultra-high image density (UHD). These large-size OLED panels were driven by using a novel gate driver circuit not only for displaying images but also for sensing TFT characteristics for external compensation. Regardless of the negative threshold voltage of the TFTs, the proposed gate driver circuit in OLED panels functioned precisely, resulting from a decrease in the leakage current. The falling time of the circuit is approximately 1.6 μs, which is fast enough to drive UHD OLED displays at 120 Hz. 120 Hz is most commonly used as the operating voltage because images consisting of 12 frames per second can be quickly shown on the display panel without any image sticking. The reliability tests showed that the lifetime of the proposed integrated gate driver is at least 1 × 105 h.

Abstract An ionic wind pump is an energy-saving device that can produce a volume flow when electrodes are applied with high voltage. Compared to the traditional methods, ionic wind pumps possess the advantages of low energy consumption, no moving parts, compact structure and flexible design. In this study, a large-size ionic wind pump, consisting of many single regular hexagonal needle-ring ionic wind generators, was developed as the preliminary model. However, its experimental performance was not as good as our expectations. In order to improve this preliminary model, a simulation method was used to investigate the configuration factors of the single ionic wind pump. In the optimized model, mesh gap is 6 mm, eccentricity is 0.26, section area is 238.44 mm2 and needle electrode number is 3. In subsequent experiments, the final optimized large-size ionic wind pump showed a great promotion in velocity, and the maximum average velocity of the optimized pump was higher than the preliminary model by 13.3%. Our numerical simulation and experiment results have practical significance in designing ionic wind pumps. Highlights • A 3D numerical model is established for large size ionic wind pump. • Influences of multi-parameter on the performance of ionic wind pump are investigated by numerical and experimental method. • Optimized large-size ionic wind pump showed a great promotion in velocity. [ABSTRACT FROM AUTHOR]

Abstract Large-size ultrathin g-C 3 N 4 nanosheets have attracted extensive attention for their peculiar properties and promising practical application. Temporarily, g-C 3 N 4 nanosheets are mostly obtained through thermal oxidation etching of bulk g-C 3 N 4 which generally introduces defects including oxygen doping impurities. Here, we construct high-quality g-C 3 N 4 nanosheets with thickness of about 2 nm and large lateral size up to 4 µm by hydrogen atom etching of bulk g-C 3 N 4. The as constructed large-size ultrathin g-C 3 N 4 nanosheets exhibit an enhanced photoluminescence with a quantum yield about two times that of the bulk g-C 3 N 4. This work employs a facile method to prepare large-size g-C 3 N 4 , providing great guidance to the synthesis of other materials with similar structure. [ABSTRACT FROM AUTHOR]

Two-dimensional layered transition metal dichalcogenides (TMDCs) are highly promising in field-effect-transistors (EFTs), photodetectors, flexible devices, but the limitation of uncontrollable size and number of layers is a huge challenge for the development of these devices. Although some breakthroughs like wafer-level MoS 2 have been achieved on specific substrates such as copper foil or sapphire using advanced chemical vapor deposition, electrical and optoelectronic testing requires the transfer of material from these substrates to SiO 2 /Si substrates. In this paper, we developed a face-to-face confined space CVD scheme for the preparation of centimeter-level MoS 2 thin films on amorphous SiO 2 /Si substrate. In contrast to traditional confined-space CVD scheme where the MoO 3 powder is often piled like a small hill in the small quartz boat, The MoO 3 powder is evenly spread in the small quartz boat, facing directly up to the growing substrate with a "face-to-face" growth mode. Therefore, the nucleation centers are uniformly distributed on the growing substrate, finally resulting in a uniform and clean continuous film originating from the coalescence of numerous MoS 2 domains grown up from these nucleation centers. The layer number can be well controlled by adjusting growing parameters like growing temperature, gas flow rate and growth time. Our facile but robust face-to-face growth strategy may be a great supplementary to the wafer-level growth of 2D TMDCs. • We developed a face-to-face confined space CVD method. • We achieved centimeter-level MoS 2 films by this method. • The resultant films are uniform, continuous and clean. • The layer number can be well controlled. [ABSTRACT FROM AUTHOR]

The full-image based kernel estimation strategy is usually susceptible by the smooth and fine-scale background regions impacting and it is time-consuming for large-size image deblurring. Since not all the pixels in the blurred image are informative and it is frequent to restore human-interested objects in the foreground rather than background, we propose a novel concept “SalientPatch” to denote informative regions for better blur kernel estimation without user guidance by computing three cues (objectness probability, structure richness and local contrast). Although these cues are not new, it is innovative to integrate and complement each other in motion blur restoration. Experiments demonstrate that our SalientPatch-based deblurring algorithm can significantly speed up the kernel estimation and guarantee high-quality recovery for large-size blurry images as well. [ABSTRACT FROM AUTHOR]

A large-size, bipolar-stacked and high-safety solid-state lithium battery with integrated electrolyte and cathode is fabricated conveniently via solvent-free UV-cure. Firstly, a series of new solid polymer electrolytes are synthesized through UV-cure, and exhibit a maximum conductivity of 1.29 × 10 −4  S cm −1 (60 °C), a wide electrochemical window (0–5.1 V) and excellent compatibility with Li. Secondly, solid-state LiFePO 4 /Li cell with integrated electrolyte and electrode is fabricated and delivers a high capacity of 113.3 mAh g −1 after the 100 th cycle, and the capacity retention is 90.2%. The outstanding cell performance is ascribed to the integrated electrolyte/cathode design which is beneficial for the interfacial impedance decreasing. Finally, a 5 cm × 8 cm size battery with integrated electrolyte/cathode is assembled conveniently, and it presents the 80.55% retention of discharge capacity at the 200 th cycle and high-safety. It can be well work under the conditions of bending, cutting, on the fire and even after nail penetration. Remarkably, the bipolar-stacked battery is also fabricated, and the open circuit voltage is as high as 6.33 V. Consequently, this work develops a series of new solid polymer electrolytes and proposes an advanced cell construction design for solid-state lithium batteries which is very suitable for the large-scale preparation. [ABSTRACT FROM AUTHOR]

We present a novel OLED display panel with high‐reliability integrated gate driver circuit using IGZO TFTs. Our gate driver circuit can drive a large‐sized OLED display not only for displaying images but also for sensing TFT characteristics for external compensation. It functions correctly even when the threshold voltage of TFTs is negative by reducing leakage currents. We have achieved a life time longer than 60,000 hours in a reliability test and successfully applied it to 55‐inch UHD, 65‐inch UHD and 55‐inch FHD OLED displays, which improves cost‐competitiveness of OLED displays against LCDs. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel PCD@BNNSs composite with high dispersibility was constructed. • The large-size PCD@BNNSs showed long-range ordered arrangement feature in the coating. • The PCD@BNNSs endowed the epoxy coatings with an outstanding long-term anticorrosion property. • The superior anticorrosion performance benefited from synergistic effect of barrier and passivation of PCD@BNNSs. Large-size ultrathin 2D nanosheets show huge advantages in improving the barrier and anticorrosion properties of organic coatings. However, the irreversible agglomeration of large-size nanosheets has become a key scientific issue restricting their practical applications. Herein the in situ phosphorus-doped carbon dots (PCDs) are synthesized and decorated on large-size boron nitride nanosheets (BNNSs) matrix, to empower excellent dispersion of BNNSs (stable for a few weeks) and superlative nanosheet-matrix bonding with matrix. When served as the functional fillers for epoxy (EP) coatings, the resultant PCD@BNNS/EP composite coating shows greatly enhanced corrosion resistance due to the long-range ordered self-alignment of large-size PCD@BNNSs and strong interfacial bind with coating matrix. Typically, after 5 weeks of exposure in 3.5 wt% NaCl (aq) , the coating resistance of the PCD@BNNS/EP composite coating maintained 6.3 × 109 O cm2, 2 ∼ 3 orders of magnitude higher than those of unmodified BNNS/EP composite (8.0 × 107 O cm2) and blank (4.2 × 106 O cm2) coatings, revealing exceptional long-term anticorrosion performance. The anticorrosion mechanism was unlocked in detail by the chemical reactions at the coating-metal interfaces, owing to the arrested incursion of aggressive species through the multi-effect synergies of superior shielding property and passivation function by the intercalated large-size and self-aligned PCD@BNNSs. Our work introduces a unique binary hybrid material system to construct high-performance coatings for future marine and aviation protection. [ABSTRACT FROM AUTHOR]

To investigate the flow field characteristics of large-size plant protection unmanned helicopter hedgehopping，the numerical simulations were conducted,and the full-size physical model of the large-size helicopter was established. The three-dimensional flow field of large-size unmanned helicopter hedgehopping was simulated by SST k-ω turbulent flow model. The results show that the downwash flow field is relatively disorder under the fuselage because of the obstruction of fuselage.The distribution characteristics of downwash are generally consistent at the same nozzle location of different height，however the distribution characteristics of downwash are quite different for the same flight altitude at different nozzle location. The vertical velocity is increased with latter decreasing along the direction of rotor at the spray boom location，and the maximum velocity is obtained near the x/R value of 0.8. The width of plant canopy velocity is increased with the decreasing of flying height，and the better fly height of H is 4 m. The boom of UAV should be installed in the area with z from -1.50 to -2.00 m and x from -0.50 to 0.50 m. [ABSTRACT FROM AUTHOR]

Herein, vertical-geometry Pt/(010) β-Ga 2 O 3 Schottky barrier diodes (SBDs) with various large areas (2.25 × 10−2, 4 × 10−2 to 6.25 × 10−2 cm2) were fabricated on (010) orientation β-Ga 2 O 3 substrates. The electrical properties of different area diodes and the uniformity of diodes with the same area were analyzed. The rectifying ratio of all diodes was determined to be larger than 108 at the bias of ±2 V. The current-voltage (I–V) characteristics of SBD with an area of 2.25 × 10−2 cm2 were investigated in detail from 300 to 450 K. The parameters of the diodes show a strong dependence on temperature, including ideality factor (n), on-resistance (R on), turn-on voltage (V on), and the Schottky barrier (Φ b). The results indicate that a dominant inhomogeneous Schottky barrier exists at the Pt/β-Ga 2 O 3 interface. Such large-area devices exhibit that the value of n is close to 1 and the value of Φ b was 1.09 eV at zero bias. In addition, the V on remains low and the stability remains good even after the tests at 450 K. These results indicate that we have successfully fabricated large-area SBDs with excellent performances. This work may contribute to further understanding of the performance of β-Ga 2 O 3 diodes in large areas and harsh environments. • Large-area vertical SBD have been fabricated, exhibiting the extremely high rectifying ratio of 108. • Such large-area devices exhibit an ideal factor of 1.09, which is quite close to 1. • The devices with the large size possess good robustness at high temperature. [ABSTRACT FROM AUTHOR]

Conducting polymers (CPs) are commonly explored in electrochromic devices (ECDs) because of their designable compound structure, rich color, fast switching speed, flexibility and high coloration efficiency. However, the preparation of large-size nanostructured electrochromic polymer (ECP) films is still a great challenge. Herein, we present a facile and efficient strategy to construct neat large-size nanostructured ECP films without molecular design. Polyterthiophene (PTTh), poly(3,4-ethylenedioxythiophene) (PEDOT) and poly(2,2′-bithiophene) (PBTh) are selected as the model polymers due to their good EC behaviors. The PTTh hollow microspheres, PEDOT and PBTh nanoparticles (NPs) were prepared by in situ chemical oxidative polymerization without templates, and then were made into stable dispersions, which were processed into films by spray-coating method. The obtained films were further assembled into the ECDs. We investigated the structure, morphology and electrochemical properties of PTTh, PEDOT and PBTh films, and EC performance of corresponding ECDs. The results indicate that the uniform and loose PTTh film possesses 3D porous structure composed of many hollow microspheres, while the PEDOT and PBTh films consist of many NPs. These films exhibit good electrochemical performance. The ECD based on PEDOT film achieves an optical contrast of 29%, coloration efficiency of 217 cm2/C, and its coloration time and bleaching time are 3.48 and 0.09 s, respectively. This study suggests that in situ chemical oxidative polymerization preparation of ECP microspheres or NPs might be a facile strategy for fabricating neat large-size ECP films, and its preparation process is easily conducted, showing great potential applications in conducting polymer-based ECDs. The PTTh hollow microspheres, PEDOT and PBTh NPs were prepared by in situ chemical oxidative polymerization without templates, and then were made into stable dispersions, which were processed into films by spray-coating method. A larger device (active area: 10 × 8.5 cm2) based on PEDOT/ITO was assembled. The device can undergo reversible color changes under an applied voltage of ±3.0 V within 4 s, and displays a uniform colour switch. This work provides a simple and efficient strategy for fabricating the large-size conducting polymer-based ECDs. [Display omitted] •A facile and efficient strategy was proposed to construct neat large-size ECP films without molecular design. •The obtained ECP films composed of many hollow microspheres or nanoparticles possessed good electrochemical performance. •The larger ECD (active area: 10 × 8.5 cm2) based on PEDOT/ITO was assembled, displaying a uniform colour switch within 4 s. •The relationship of microstructure and surface morphology of ECP films to their EC properties was revealed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Large-size and flexible transparent bamboo (TB) was developed. • The "alkali pretreatment-crosslinking-delignification" strategy proposed. • Flexible TB possessed higher tensile strength (78.5 MPa) than all reported flexible transparent wood. • TB exhibited excellent optical, mechanical, and thermal properties. Transparent wood (TW) has received extensive attention recently because of its excellent optical, mechanical, and thermal properties. However, the long growth cycle of timber and forbidden deforestation regulation limit the large-scale application. Bamboo has a much shorter growth cycle than wood, but its high density and lack of lateral cell tissues make it challenging to produce transparent products. Meanwhile, fabrication of large-size transparent bamboo (TB) remains a huge challenge because of the inherent features of irregular, hollow cylindrical shape with nodes, and big culm taper. In this work, the "alkali pretreatment-crosslinking-delignification" strategy was developed to fabricate the scalable, large-size, and flexible TB from the building block of sliced bamboo veneer (SBV). The optical transmittance and haze of the TB with a thickness of 1.0 mm were approximately 80 % and 72 %, respectively, and possessed the light modulation capability. The fabricated TB exhibited flexibility, and the tensile strength was 78.5 MPa, which was higher than all reported flexible TW. Besides, the TB exhibited a low thermal conductivity of 0.35 W m−1 k−1, which had an outstanding thermal insulation and indoor temperature regulation performance. More importantly, this study demonstrated the feasibility of successful preparation of large-size TB, which can promote its large-scale and industrial application. The TB with excellent overall performance holds great potential in engineering applications, especially for energy-efficient windows, light-tunable devices, flexible transparent materials, etc. [ABSTRACT FROM AUTHOR]

High thermoelectric performance of mechanically robust p-type Bi2Te3-based materials prepared by melt spinning (MS) combined with plasma-activated sintering (PAS) method can be obtained with small, laboratory grown samples. However, large-size samples are required for commercial applications. Here, large-size p-type Bi2Te3-based ingots with 30, 40, and 60 mm in diameter are produced by MS-PAS, and the influence of temperature distribution during the sintering process on the composition and thermoelectric properties is systematically studied for the first time. Room-temperature scanning Seebeck Microprobe results show that the large-size ingot is inhomogeneous, induced by ellipsoidal-shape-distributed temperature field during the sintering process, which is verified by finite-element analysis. Although some temperature differences are unavoidable in the sintering process, homogeneity and mechanical properties of ingots can be improved by appropriately extending the sintering time and design of graphite die. Samples cut from ingots attain the peak ZT value of 1.15 at 373 K, about 17% enhancement over commercial zone-melted samples. Moreover, the compressive and bending strengths are improved by several times as well. It is important to ascertain that large-size p-type Bi2Te3-based thermoelectric materials with high thermoelectric performance can be fabricated by MS-PAS. [ABSTRACT FROM AUTHOR]

2D SnS2 nanosheets have been attracting intensive attention as one potential candidate for the modern electronic and/or optoelectronic fields. However, the controllable large-size growth of ultrathin SnS2 nanosheets still remains a great challenge and the photodetectors based on SnS2 nanosheets suffer from low responsivity, thus hindering their further applications so far. Herein, an improved chemical vapor deposition route is provided to synthesize large-size SnS2 nanosheets, the side length of which can surpass 150 μm. Then, ultrathin SnS2 nanosheet-based phototransistors are fabricated, which achieve high photoresponsivities up to 261 A W−1 (with a fast rising time of 20 ms and a falling time of 16 ms) in air and 722 A W−1 in vacuum, respectively. Furthermore, the effects of back-gate voltage and air adsorbates on the optoelectronic properties of the SnS2 nanosheet have been systematically investigated. In addition, a high-performance flexible photodetector based on SnS2 nanosheet is also fabricated with a high responsivity of 34.6 A W−1. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (Ag NPs) enjoy a reputation as an ultrasensitive substrate for surface-enhanced Raman spectroscopy (SERS). However, large-scale synthesis of Ag NPs in a controlled manner is a challenging task for a long period of time. Here, we reported a simple seed-mediated method to synthesize Ag NPs with controllable sizes from 50 to 300 nm, which were characterized by scanning electron microscopy (SEM) and UV-Vis spectroscopy. SERS spectra of Rhodamine 6G (R6G) from the as-prepared Ag NPs substrates indicate that the enhancement capability of Ag NPs varies with different excitation wavelengths. The Ag NPs with average sizes of ~150, ~175, and ~225 nm show the highest SERS activities for 532, 633, and 785-nm excitation, respectively. Significantly, 150-nm Ag NPs exhibit an enhancement factor exceeding 108 for pyridine (Py) molecules in electrochemical SERS (EC-SERS) measurements. Furthermore, finite-difference time-domain (FDTD) calculation is employed to explain the size-dependent SERS activity. Finally, the potential of the as-prepared SERS substrates is demonstrated with the detection of malachite green. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

We have employed a one-step (direct etching) metal-assisted chemical etching (MACE) technique to grow large-area Si nanostructures with smoother surface morphology and much less porous Si (PS) defects than those under the two-step (depositing and etching) MACE. A 17.63%-efficiency of the nano/ microstructures (N/M-Strus) based multicrystalline Si (mc-Si) solar cells has firstly surpassed that (17.45%) of traditional-micro-textured one with a standard solar wafer size of 156×156 mm 2 . The key to success lies in the reduction of electrical loss by removing PS defects and employing shorter one-step-MACE-smoothened N/M-Strus, together with the optical gain from the combined antireflection of mc-Si N/M-Strus and SiN x :H thin films. The present work opens a way to the mass production of high efficient Si nanostructures based solar cells with a less-process-step and lower-cost approach. [ABSTRACT FROM AUTHOR]

Luminescent solar concentrators (LSCs) offer an attractive approach to combine spectral and spatial concentration of both direct and diffuse light without the expensive tracking system. In this study, different size glass laminated luminescent solar concentrators (GL-LSCs) of 7.8 × 7.8 cm 2 , 15.6 × 15.6 cm 2 , 31.2 × 31.2 cm 2 and 61 × 122 cm 2 were fabricated by using fluorescent dyes Lumogen Red 305 and Yellow 083, ultra-white glass and commercial mono-crystalline silicon solar cells. With the size increase, the output power of the GL-LSCs increases, but the power conversion efficiency (PCE) decreases rapidly due to the transport losses and re-absorption of luminescent materials. As a result, a series of GL-LSCs with bottom-mounted PV cells were fabricated to enhance the PCE. The relationship between the area of luminescent waveguide and the gain of the bottom-mounted PV cells was investigated for the optimization of the GL-LSCs performance. Among them, a highest gain of 1.38 in power over the bare PV cells was obtained with PV cell coverage of 4.54%. A highest PCE of 2.28% was achieved with PV cell coverage of 11.32%. It was found that the design with PV cell coverage of 9.07% have the lowest cost of $ 1.25/W P with a PCE of 2.02% and a gain of 1.27. [ABSTRACT FROM AUTHOR]

In the background of polar research robot equipment, this paper presents a kind of control system of large-size spherical robot, and resolves the problems of balance and motion control of spherical robot by fuzzy control algorithm. Through comparison among different control methods, we took one practical and feasible way. On the basis of balance problem, we proposed a relative control strategy. Especially on the problem of the deflection of minor axis, we analyzed it and further designed a specialized fuzzy controller to control the deflection of this robot, this helped to solve the uncontrollable problem of the robot. The algorithm easily suffers from environmental influence, for this reason, we proposed a kind of optimization algorithm based on reference model by correcting coefficient. It can make the algorithm adapt environment automatically when the landform remain unchanged and implement control of the robot by amending the parameter of fuzzy algorithm's output. Finally, we implemented a motion control experiment for our self-design robot. The experimental data showed the validity and practicability. [ABSTRACT FROM AUTHOR]

High-efficiency blue phosphorescence devices with external quantum efficiencies above 25% are developed using a new bipolar host material, diphenyl(10-phenyl-10 H-spiro[acridine-9,9′-fluoren]-2′-yl)phosphine oxide (POSTF), which is constructed in orthogonal molecular structure with a spiro-coree. The separation of bipolarity from effective spiro-fluorene-triphenylamine (STF) structure is elucidated and its versatility in device is evaluated by two kinds of sky-blue phosphors. Noticeably, large-size white light-emitting panel (150 mm × 150 mm) is fabricated with max power efficiency of 75.9 l m W−1 using this new host. [ABSTRACT FROM AUTHOR]

Here, we propose a facile strategy to realize all-solution-processed highly efficient full-color-enabling white emitting quantum dot light-emitting diodes (QLEDs) at ambient conditions by using low-cost blade coating technique, which was also compatible with the roll to roll fabrication process for large size production. Firstly, by using red quantum dots (QDs) as the representative to optimize the QDs films by blade coating, the QDs films exhibit excellent morphology and well-ordered self-assembly structure. Then, the trichromatic white QLEDs based on mixed red, green and blue quantum dots were obtained with Commission Internationale De I'Eclairage (CIE) coordinates ranging from (0.42, 0.41) to (0.31, 0.33) within the white region of CIE 1931 when driving voltage vary from 5 v to 8 v. The device enjoys excellent optoelectronic performance including a maximum luminance of 11,465 cd/m2, a maximum current efficiency (η A) of 9.2 cd/A and an external quantum efficiency (EQE) of 3.7%. In addition, 3 × 8 cm2 white QLEDs with bright and homogenous light emission fabricated by blade coating are demonstrated. Our strategy for fabricating large-area white QLEDs indicate promising applications in the low-cost solid-state lighting and flat-panel displays. Image 1 • The QDs films exhibit excellent morphology and well-ordered self-assembly structure by blade coating. • The trichromatic white QLEDs were obtained with a maximum luminance of 11,465 cd/m2, η A of 9.2 cd/A and EQE of 3.7%. • 3×8 cm2 white QLEDs with bright and homogenous light emission fabricated are demonstrated. [ABSTRACT FROM AUTHOR]

• A green and eco-friendly technical route of two-dimensional nanosheets was proposed. • The conversion from natural graphite to few-layer graphene is ~100%. • No water-washing and effluent-treatment are involved during the exfoliation process. • The graphene paper behaves excellent electrical conductivity to 7.36 × 105 S/m. • The 4-um-thick-graphene paper exhibits a record-high EMI SE value to 61 dB. Eco-friendly exfoliation of two-dimensional nanosheets from their layered bulks is very attracting but still remains a big challenge. Here, we report a novel preparation route of two-dimensional nanosheets through soaking the bulk layered material in the C 2 H 4 O 3 -based chemical exfoliation system followed by microwave irradiation. This route has demonstrated the effective exfoliation of two-dimensional nanosheets (graphene nanosheets, BNNS and MoS 2 NS) from their layered bulks in a green and eco-friendly way. The average layer-number of the obtained graphene nanosheets, BNNS and MoS 2 NS is 4, 6 and 5, respectively, behaving a few-layer feature. Interestingly, when the graphene paper is prepared from the exfoliated graphene nanosheets by simple vacuum filtration and mechanical pressing, its average electrical conductivity is up to 7.36 × 105 S/m and the EMI SE value reaches to 61 dB, both among the highest for the graphene papers reported previously. Since there exists no serious fragmentation of layered materials during the whole exfoliation, the present exfoliation strategy is more competent in preparing the large-sized two-dimensional nanosheets over those conventional green routes. [ABSTRACT FROM AUTHOR]

The gradient microstructure and deformation mechanisms of an as-cast 6 mm-diameter ZrCuAl metallic alloy are investigated using optical microscope (OM), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The metallic alloy with gradient microstructure in both phase constituent and grain size from surface to core is prepared based on a fast cooling technique. The quasi-static mechanical property of the alloy is studied and it is found that a good combination of strength-ductility, as well as low Young's modulus and high fracture strength of the alloy are achieved due to the suppression of the strain localization. Combined study of SEM and TEM on deformation mechanisms shows that the gradient microstructure with martensitic transformations, twinnings and dislocations contributes to the enhanced mechanical properties of the large-size metallic alloy. [ABSTRACT FROM AUTHOR]