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The performance of a solar-assisted DX-PVT heat pump (direct expansion photovoltaic-thermal) is intimately relevant to the system configuration. Inappropriate system configuration will undermine the system performance. This work assessed the effect of the equipment area of PVT modules on the PVT heat pump system driven by novel direct-expansion roll-bond PVT modules, and aimed to propose optimal system configuration. An analytical model was developed for the PVT heat pump system and validated by the experimental results. Simulations were conducted to reveal the effect of A / V t h , a proposed parameter to describe the system configuration, namely the ratio of the modules' area to the theoretical displacement of the compressor. The results showed that the larger A / V t h lead to higher COP but lower HGF (heat gain factor). With A / V t h increasing from 0.768 to 2.303 m2 h/m3, the COP increases by 61.3% (from 3.1 to 5.0) but the HGF decreases by 39.6% (from 0.91 to 0.55). Higher levels of solar irradiation strengthens the positive effect of the increasing A / V t h on thermodynamics performance and weakens the negative effect of that on the heat collection performance. The enhancement in COP is 42.8%/70.9% with A / V t h increasing from 0.768 to 2.303 m2 h/m3 when solar irradiation is 500 W/m2/800 W/m2, while the decrease in HGF is 49.2%/39.2%, respectively. A configuration optimization was also conducted to balance the thermodynamics and heat collection performance. The A / V t h varying from 1.535 to 1.919 m2 h/m3 was suggested as the optimized configuration when solar irradiation is 500 W/m2. After optimization, the IPLV and HGF can exceed that of air-source heat pump and flat-plate collectors by 40%, showing considerable performance advantages. [ABSTRACT FROM AUTHOR]

The mass transfer and related electrochemical reactions in the catalytic layer (CL) are crucial for the performance of high-temperature polymer electrolyte membrane fuel cells (HT-PEMFCs), but there is a lack of understanding of the optimal phosphoric acid content and Pt/C catalyst loading in the CL. In this work, we investigate the influences of Pt/C catalyst numbers (N Pt/C) and phosphoric acid film thickness (δ PA) on mass transfer and electrochemical reactions of the cathode CL using a pore-scale model (300 × 300 × 300 nm3). The results reveal that larger N Pt/C and δ PA can impede oxygen diffusion, while lower N Pt/C and δ PA lead to fewer reaction active sites and lower conductivity, both of which result in lower current density. Therefore, the balance of three-phase transport is extremely important for CL. There is a 3D volcanic relationship between current density, Pt/C catalysts, and phosphoric acid film. At N Pt/C = 200 (7407 per μm3) and δ PA = 4 nm (the volume fractions of 37.22 % and 17.87 %), the highest current density can be achieved at a potential of 0.5 V (vs. RHE), which increased with the decrease of potential. This work is valuable for understanding the optimizing the microstructure and three-phase transport pathway of the CL to improve the performance of HT-PEMFCs. • Catalyst layer is reconstructed numerically in a HT-PEMFCs with a pore-scale model. • The influence of Pt/C catalyst number and phosphoric acid film thickness is studied. • The balance between the three phases of the transmission pathway is very important. • A 3D volcano-shaped relationship is obtained to describe the current density, N Pt/C and δ PA. [ABSTRACT FROM AUTHOR]

The industry widely uses WC coatings to protect vital machine parts, including industrial gas turbines, ball valves, and aircraft landing gear shafts. To enhance the comprehensive performance of WC-10Co cemented carbide coatings, this study added VC and Cr 3 C 2 grain inhibitors to refine the WC particles. Two novel powder compositions, S1 (WC-10Co-2Cr 3 C 2 -2VC) and S2 (WC-10Co-2VC-2Cr) were developed using the spray granulation method, alongside a commercial WC-10Co-4Cr powder as a control. These coatings were applied to 316 stainless steel substrates using the HVOF technique and subjected to XRD, SEM, hardness, friction, and electrochemical analysis. The microstructures, phase compositions, and various properties of WC-10Co-2Cr 3 C 2 -2VC and WC-10Co-2VC-2Cr coatings were systematically investigated. The results indicate a significant reduction in decarburization and porosity in S1 and S2 coatings compared to the commercial WC-10Co-4Cr coatings. VC and Cr 3 C 2 suppressed the Ostwald ripening phenomenon, leading to smaller WC particle sizes in S1 and S2 coatings. In terms of performance, WC-10Co-2Cr 3 C 2 -2VC exhibited the highest hardness and superior wear resistance, while the WC-10Co-2VC-2Cr coating displayed the lowest corrosion rate in a 5 wt% H 2 SO 4 solution at 25 °C, all while maintaining excellent mechanical properties. This study opens potential directions for the creation of high-performance WC-based coatings. • VC and Cr 3 C 2 suppressed the Ostwald ripening phenomenon, leading to smaller WC particle sizes. • WC-10Co-2Cr 3 C 2 -2VC exhibited the highest hardness and superior wear resistance. • WC-10Co-2VC-2Cr coating displayed the lowest corrosion rate in a 5 wt% H 2 SO 4 solution at 25 °C. [ABSTRACT FROM AUTHOR]

Semiconducting single-walled carbon nanotube (s-SWCNT) films require high-quality preparation and optimization for use in carbon-based electronic devices. Tremendous progress has been made in s-SWCNTs sorting technology with conjugated polymers to obtain high-purity s-SWCNT films. However, one drawback of this technology is residual polymer wrapping on s-SWCNT surfaces. These residual polymers have poor conductivity, impeding the charge transport between the nanotube-electrode and the nanotube-nanotube. To address this issue, a rapid annealing and cooling method was developed for cleaning the s-SWCNT films, which can thoroughly remove the wrapped polymers from the surfaces of s-SWCNTs, effectively reducing the contact resistance between the nanotube-metal electrode and the nanotube-nanotube. Our results show that thin-film transistors made of cleaned s-SWCNTs exhibited improved performance when compared with pristine s-SWCNT films rinsed with an organic solvent. The contact resistance between the s-SWCNTs and the electrode was reduced by 700%, while the on–state current density of the CNT-TFTs increased by nearly 600%. These results thus demonstrated the effectiveness of our developed method for removing polymers from the surfaces of s-SWCNTs, which is essential for the further development of carbon nanotube electronic devices and circuits. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • An ETSC with inner concentrating by reflective coating was proposed and fabricated. • The best coating angle was 180° and efficiency increased with eccentric distance. • The thermal efficiency of the novel inner concentrating ETSC was increased by 10%. • The heat loss coefficient of the ETSC-IC was decreased by 27% to 48%. Evacuated tube solar collector (ETSC) is widely used for domestic and industrial applications. Using reflective coating in an ETSC to realize concentration is a method to heighten the thermal efficiency due to solar irradiation could be reflected by the coating on the lower half of the outer glass tube and concentrated to the eccentric inner absorber. In this paper, an evacuated tube solar collector with inner concentrating (ETSC-IC) by reflective coating was proposed and fabricated. A series of experimental tests of the ETSC-IC was conducted to investigate the thermal performance. In addition, the mathematical model of the novel collector with inner concentrating was developed, and the structural parameters of the inner reflective concentrating evacuated tube, including the coating angel and the eccentric distance, have been analyzed. The optical and thermal analysis revealed that the best coating angle of the evacuated tube was 180°, and the thermal performance of the ETSC-IC enhanced with the increase of the eccentric distance under the best coating angle. The thermal efficiency of the ETSC-IC could reach 0.65 to 0.72 on the condition that the solar irradiation was around 950 W/m2 and the temperature of inlet water varied between 45 °C and 70 °C, and the ambient temperature was 31.2 °C. The thermal efficiency of the ETSC-IC was improved by approximately 10% compared with the conventional evacuated tube due to the enhanced irradiation concentrating and the reduction of heat loss caused by the coating on the outer glass tube. [ABSTRACT FROM AUTHOR]

The explosion characteristics of diethyl ether-Al mixtures under different ambient pressure (57.4–101.3 kPa), temperature (263–333 K), and relative humidity (48.3–90%) were investigated in a 20 L explosion vessel. The explosion pressures and lower flammability mass concentration limits of diethyl ether-Al mixture under different ambient conditions were obtained after a series of experiments. The components of explosion exhaust gas and the morphologies of solid residues were examined by a gas detector and a scanning electron microscope, respectively. The results showed that the ambient pressure had a greater influence on the explosion pressure of diethyl ether-Al mixtures than ambient temperature and relative humidity, while the ambient temperature had a greater influence on the lower flammability mass concentration limit than ambient pressure and relative humidity. The explosion exhaust gases were mainly composed of CO and CO 2 with a small amount of NO and NO 2 , and the solid residues were mainly composed of Al 2 O 3 and unreacted Al. The effect mechanism of different ambient conditions on the explosion of diethyl ether-Al mixture was discussed based on these results. [ABSTRACT FROM AUTHOR]

Borehole heat exchanger (BHE) is a promising method for extracting heat from the deep geothermal energy which has been widely used for residential heating in high latitude areas. The solar assisted photovoltaic/thermal (PV/T) heat pump could convert solar energy into useful heat efficiently, and could be further used to heat water from the BHE to a higher temperature level. In this paper, a residential heating system using BHE coupled with solar assisted PV/T heat pump is therefore proposed with further performance analysis. The simulation results show that a larger mass flow rate could increase the BHE's heat extract capacity but also increase the flow resistance and pump power under nominal conditions. The circulating water would not extract heat from rock-soil if the inlet temperature exceeds 48.5 °C when mass flow rate is 12 kg/s. Furthermore, the maximum water temperature from this hybrid system could reach 40.8 °C while the solar fraction is 67.5% when the area of PV/T module is 1000 m2, solar irradiation is 600 W/m2 and depth of the BHE is 2500 m. In the meantime, the heating COP of this hybrid system could reach 7.4 and the system could operate independently without power input from electrical grid. • A hybrid residential heating system using borehole heat exchanger coupled with solar assisted PV/T heat pump is proposed. • The structure and operating parameters of this hybrid system have been analyzed. • The heating COP of this hybrid system could reach 7.4, while the solar fraction is 67.5%. • The maximum thermal effect radius of a 2500 m borehole heat exchanger is within 8 m. • Higher mass flow rate and inlet temperature lead to lower heating COP and temperature difference between outlet and inlet. [ABSTRACT FROM AUTHOR]

• The efficiency factor of direct expansion PVT module is derived and validated. • Proposed a novel design method for PVT module employing roll-bond evaporator. • Parameter analysis is conducted to evaluate the thermal performance of four different channel patterns. • Hexagon and rectangle types have better temperature uniformity while grid and linear types have lower pressure loss. Direct expansion solar assisted PVT (photovoltaic/thermal) heat pump is a combination of PVT technology and heat pump technology, which can improve the comprehensive conversion efficiency of solar energy, and it is suitable for solar heating applications. In this paper, the efficiency factor of direct expansion PVT module employing roll-bond panel has been theoretically derived, modified, and validated by experimental results. Moreover, the efficiency factor could be used to design, evaluate, and optimize the thermal performance of direct expansion solar assisted heat pump systems. In addition, parameter analysis of four evaporator unit types has been conducted, and the recommendation values of each parameter have also been presented. The simulation results show that the roll-bond evaporator (fluid channel width: 10 mm) with hexagon and rectangle patterns have better temperature distribution uniformity than grid and linear types, and their temperature differences are both 0.038 °C while their dimensionless pressure losses are 0.109 and 0.230, respectively. To specifically design different kinds of PVT collector/evaporator or direct expansion evaporators, a novel design method for roll-bond evaporator is proposed, and a combination of hexagon and grid types is recommended for PVT module. Moreover, the recommendation fluid channel width of the roll-bond panel is 8 mm to 13 mm while the scaling ratio is 0.8 to 1.2. The modified efficiency factors are 0.521, 0.564, 0.549, and 0.342 of hexagon, grid, rectangle, and linear types when the fluid channel width is 10 mm, respectively. [ABSTRACT FROM AUTHOR]

Haemophilia is a blood clotting disorder known as 'Christmas disease' caused when the blood has defect with the clotting factor(s). Bleeding leads various issues, such as chronic pain, arthritis and a serious complication during the surgery. Identifying this disease is mandatory to take the necessary treatment and maintains the normal clotting. It has been proved that the level of factor IX (FIX) is lesser with haemophilia patient and the attempt here is focused to quantify FIX level by interdigitated electrode (IDE) sensor. Single-walled carbon nanotube (SWCNT) was utilized to modify IDE sensing surface. On this surface, dual probing was evaluated with aptamer and antibody to bring the possible advantages. The detection limit with antibody was found to be 1 pM, while aptamer shows 100 fM. Further, a fine-tuning was attempted with sandwich pattern of aptamer-FIX-antibody and antibody-FIX-aptamer and compared. Specific elevation of detection with 10 folds was noticed and displayed the detection at 100 f. in both sandwich patterns. In addition, FIX was detected in the diluted human serum by aptamer-FIX-antibody sandwich, it was found that FIX detected from the dilution factor 1:640. A novel demonstration is with higher discrimination against other clotting factors, XI and VII. [ABSTRACT FROM AUTHOR]

• A solar PV/T heat pump is proposed for residential heating in high latitude area. • Design of build-in PCM heat storage unit is proposed and simulated. • The overall efficiency of this solar PV/T heat pump system can reach above 75%. PV/T (photovoltaic/thermal) technology is a combination of PV module (photovoltaic utilization) and collector (photothermal utilization), which can improve the comprehensive utilization efficiency of solar energy and has a broad application prospect. In this paper, PV/T module is coupled with heat pump evaporator to form a direct-expansion solar PV/T heat pump which is suitable for heat application in high latitude area. To achieve stable residential heating, a solar PV/T heat pump system coupled with build-in PCM (phase change material) heat storage is therefore proposed and simulated. Meanwhile, the mathematical model of solar PV/T heat pump coupled with build-in PCM heat storage system is established and verified. The simulation results show that the temperature of underfloor heating which using build-in PCM heat storage can reach 22–31 °C after 39 h when the circulating water is 40 °C. Moreover, the heating COP (Coefficient of Performance) increases with the increase of solar radiation, ambient temperature and area of PV/T collector, and decrease of wind speed, respectively. A 20 m2 PV/T panel module can output 21.4% of the electricity to power grid when the solar radiation intensity is 600 W/m2 and meet the heat demand of a 100 m2 room while maintain the operation of the system. Meanwhile, the heating COP can reach 5.79 which is 70% higher than the conventional air conditioning system and the electrical, thermal, overall efficiencies are 17.77%, 55.76% and 75.49%, respectively. [ABSTRACT FROM AUTHOR]

During pressurized thermal shock (PTS) transient, the surface crack near the inlet nozzle region of a reactor pressure vessel (RPV) may propagate constantly and even through the thickness of base wall. The temperature dependent material properties are introduced to evaluate the thickness effects of base wall and inlet pipe on the integrity of the structure. By means of elastic and elastic-plastic fracture analysis, the different ultimate internal pressure values related to nil-ductility reference temperature for various base wall thicknesses are compared. It is confirmed that the elastic-plastic fracture analysis is more applicable for relatively low nil-ductility reference temperatures. It is also found that the results obtained by the XFEM are in good agreement with those obtained by the traditional K-T method in case of brittle initiation. Then the thickness effects of inlet pipe on the structural integrity are emphatically analyzed. Also, the effect of crack sizes on the bearing capacity of the nozzle region is demonstrated by crack propagation paths and damage degrees. To avoid brittle fracture, the allowable inlet pipe thicknesses corresponding to various crack sizes in a wide range of reference temperatures are obtained. The proposed method has a good ability to predict the integrity of the RPV structure through the analysis, comparison and mutual verification of different finite element meshes. • A 3-D finite element model is established for the beltline around the inlet nozzles of reactor pressure vessels. • The XFEM are used to simulate the crack propagation for different thicknesses of base wall and inlet pipe under pressurized thermal shock. • By comparing the results of elastic and elastic-plastic fracture analysis, the law of ductile-brittle transition is summarized. [ABSTRACT FROM AUTHOR]

Color correction across multiple images for consistency is a challenging problem in image mosaicking. To facilitate the global color optimization, existing methods mainly use less flexible correction models, e.g., linear or gamma function, which often struggle to cover the practically existing color discrepancy. In this paper, we present a novel color consistency correction method that models the color remapping function with a parameterized spline curve for each image. Thanks to the flexible model representation, on the one hand, our method has the capability to handle very challenging cases, i.e. hundreds of images with drastic color discrepancy; On the other, some important image properties, e.g., image gradient, contrast, and dynamic range, can be effective formulated with model parameters. Thus, the visual quality of individual images, along with the global color consistency, are comprehensively considered in our specifically designed cost function, which is solved in a closed form via convex quadratic programming. In addition, considering the possibly existing alteration objects within inter-image overlaps, we also propose an functional change detection algorithm with gradient and color features utilized, which guarantees the accuracy of the extracted color correspondences. We have tested the proposed approach on several challenging dataset of diverse genres, which shows that our method substantially outperforms state-of-the-art methods in both visual quality and quantitative metrics. [ABSTRACT FROM AUTHOR]

Here we propose to employ electron beam surface melting (EBSM) to refine microstructural length scale and obtain suited microstructure morphology of Nb-Si based alloys. As characterized by scanning transmission electron microscopy (STEM) and atom probe tomography (APT), nano-lamellar eutectics are created in Nb-20Si (at.%) alloys upon EBSM. Theoretical analysis based on the competitive growth models demonstrates the preferred formation of Nb solid solution (Nbss)/Nb 3 Si eutectics under selected processing parameters. The large cooling rate during EBSM, higher than 8 × 104 K/s, promotes the formation of the nano-scale eutectics. Compared to the initial coarse eutectics by arc melting, simultaneous enhancement of hardness and fracture toughness is enabled owing to the controlled microstructural length scale and morphology. Display Omitted • Nano-lamellar eutectics are created by electron beam surface melting. • Theoretical analysis based on the competitive growth models is performed. • Simultaneous enhancement of hardness and fracture toughness is achieved. [ABSTRACT FROM AUTHOR]

[Display omitted] Reducing the usage of Sc element, as well as improving the thermal stability of nano-precipitate L1 2 –Al 3 Sc are critical in expanding the application field of Al–Sc based alloys. Previous experiments showed that the impurity Si plays a leading role in accelerating the precipitation and strengthening the thermal stability of Al–Sc-Zr alloy, but the micro mechanism of these effects are not be given at atomic and electron scale. Herein, we performed a first-principles calculations to focus on the segregation behaviors of Si and Zr at Al (0 0 1)/L1 2 -Al 3 Sc (0 0 1) interface. The results show that the ahead segregated Si atom, which prefers to occupy the Al site of Al 3 Sc precipitate side, contributes to induce Zr substituting the Sc atom that is the nearest neighbor of Si rather than the Sc site in Al matrix side. A quantitative calculation suggests that the reduction of Sc usage can at least reach 12 % as the concentration of added Si in Al bulk is about 0.06 %. [ABSTRACT FROM AUTHOR]

Abstract Automatic crack detection from images of various scenes is a useful and challenging task in practice. In this paper, we propose a deep hierarchical convolutional neural network (CNN), called as DeepCrack, to predict pixel-wise crack segmentation in an end-to-end method. DeepCrack consists of the extended Fully Convolutional Networks (FCN) and the Deeply-Supervised Nets (DSN). During the training, the elaborately designed model learns and aggregates multi-scale and multi-level features from the low convolutional layers to the high-level convolutional layers, which is different from the standard approaches of only using the last convolutional layer. DSN provides integrated direct supervision for features of each convolutional stage. We apply both guided filtering and Conditional Random Fields (CRFs) methods to refine the final prediction results. A benchmark dataset consisting of 537 images with manual annotation maps are built to verify the effectiveness of our proposed method. Our method achieved state-of-the-art performances on the proposed dataset (mean I/U of 85.9, best F-score of 86.5, and 0.1 s per image). [ABSTRACT FROM AUTHOR]

Abstract The performance of tungsten heavy alloys (WHAs) is related to the characteristic of matrix/W interfaces, which depends directly on the wettability of the matrix materials on W. This work designs a novel WHA that selects an AlCrFeNiV-system high entropy alloy (HEA) as matrix based on its wetting behavior on polycrystalline W. The wetting experiments show that this W/HEA system exhibits low contact angles at the temperatures for liquid phase sintering (LPS), and dissolutive wetting with a moderate W solubility in the HEA. This favorable wetting behavior benefits the densification process during LPS, leading to clean matrix/W interfaces with high bonding strength and hence a high ultimate tensile strength of 1132 MPa in the resulting W/HEA composite. These results indicate that the AlCrFeNiV-system HEA is a promising matrix material for WHAs. Graphical abstract Image 1 Highlights • A novel tungsten heavy alloy using high entropy alloy as matrix (W/HEA composite) is prepared by liquid phase sintering. • Dissolutive wetting of W by HEA melt with low contact angles is investigated. • W/HEA composite has fine W particle size of 13.15 μm and strong interfacial bonding. • W/HEA composite has a high yield strength of 705 MPa and high ultimate tensile strength of 1132 MPa. [ABSTRACT FROM AUTHOR]

Abstract We report the significant effect of Ti substitution on GFA and mechanical properties of Ni-free Zr-based BMGs. A series of Zr 65-x Ti x Cu 17.5 Fe 10 Al 7.5 (x = 0, 2, 4, 6, 8) bulk alloys were fabricated by the injection copper-mold casting method, and new Zr 65-x Ti x Cu 17.5 Fe 10 Al 7.5 BMGs with Ti content of 2–6 at.% were developed. Both the GFA and mechanical properties of the Zr 65-x Ti x Cu 17.5 Fe 10 Al 7.5 alloys are significantly enhanced with the increase of Ti content up to 4 at.%. The as-prepared quinary Zr 61 Ti 4 Cu 17.5 Fe 10 Al 7.5 BMG shows the largest supercooled liquid region width of 86 K, compressive fracture strength of 1915 MPa and compressive plasticity of 11.4%, which are much higher than 38 K, 1745 MPa and 3.0% of the pristine Zr 65 Cu 17.5 Fe 10 Al 7.5 BMG. Highlights • New Ni-free quinary Zr-Ti-Cu-Al-Fe BMGs have been prepared. • The GFA and mechanical properties are significantly enhanced by Ti substitution for Zr. • The Zr 61 Ti 4 Cu 17.5 Fe 10 Al 7.5 BMG exhibits a supercooled liquid region width of 86 K and a compressive plasticity of 11.4%. [ABSTRACT FROM AUTHOR]

Abstract The Ti 44.5 Ni 44.5 Nb 9 Co 2 alloys with different cold rolling ratios were annealed at 650 °C to investigate the influence of cold rolling ratio on the microstructure and recovery properties. The change in cold rolling ratio remarkably affected the distribution of β -Nb phase and the density of dislocations and precipitates. The density of dislocations increased with the increase of cold rolling ratio, which facilitated preferential nucleation and growth of Ti 2 Co precipitates. Meanwhile, high density of dislocations and precipitates retarded the recovery and recrystallization process. Owing to the strengthening effect of dislocations and nanoscale precipitates, the 40% cold rolled Ti 44.5 Ni 44.5 Nb 9 Co 2 alloy annealed at 650 °C after 16% pre-strain exhibited 25% enhancement in the total recovery strain and over 50% improvement for the recovery stress compared to the typical Ti-Ni-Nb alloys. Graphical abstract Image 1 Highlights • Prior cold rolled deformation plays important role on the microstructure of alloy. • High-density precipitates and dislocations can improve recovery properties. • The recovery strain of the alloy annealed at 650 °C after 16% strain shows 13.25%. • The recovery stress of the alloy annealed at 650 °C after 16% strain shows 584 MPa. • The alloy possesses wide transformation hysteresis and better recovery properties. [ABSTRACT FROM AUTHOR]

Abstract Hierarchically porous carbons were prepared through triconstituent co-assembly of resols, oligomer silicates from tetraethyl orthosilicate (TEOS) and triblock copolymer F127 template, followed by carbonization and removal of silica. The as-prepared carbons possess abundant micropores and two kinds of mesopore with sizes of 3.7 and 6.3 nm. Upon the electrochemical testing against sodium, the hierarchically porous carbon electrodes exhibit sloping voltage profile during the first charge and subsequent cycles with superior electrochemical performance, delivering a reversible capacity of 180 mAh g−1 at 0.1 A g−1 after 200 cycles, which is much higher than 120 mAh g−1 of the hierarchically porous carbon electrode without the addition of TEOS during the synthesis. The improved electrochemical performance may be ascribed to the combined contribution from the finer graphitic domain, higher degree of structural disorder, more abundant surface functional groups and most importantly, interconnected hierarchically mesoporous structure. Highlights • Facile method for the preparation of hierarchically porous carbons. • The structural features of the carbons herein are beneficial to Na+ storage. • The hierarchically porous carbon offers a high reversible capacity upon cycling. [ABSTRACT FROM AUTHOR]

Highlights • An arabinogalactan, HH1-1 was purified and characterized from Carthamus tinctorius. • The backbone of HH1-1 was composed of 1,6-linked Gal p branched at its C-3. • The branches contained 1,5-linked/1,3,5-linked, T-arabinose and T-galactose. • HH1-1 had immune-enhancing activity by activating NF-κB signaling. • HH1-1 could also induce TNF-α, IL-1β and iNOS expressions. Abstract Previous studies showed that polysaccharides from flowers of Carthamus tinctorius L. had immunomodulating activities. However, their structures were little known. Here, an arabinogalactan, named as HH1-1 with a relative molecular weight of 70.9 kDa, was isolated from flowers of Carthamus tinctorius L. by hot water extraction, followed by purification of a DEAE-Cellulose 32 column and a Sephacryl S-200HR column, subsequently. The structure of HH1-1 was evaluated to have a backbone of 1,6-linked Gal p branched at C-3 by side chain of 1,3-linked Gal p , with sub-branches attached at its C-3 position. The branches mainly contained 1,5-linked, 1,3,5 linked, terminal arabinose and terminal galactose. Biological activity assays showed that this polysaccharide had immune-enhancing activity by multiple ways, including promoting immune responses by activation of NF-κB signaling and increasing TNF-α, IL-1β and iNOS expressions in lymphocytes and macrophages. [ABSTRACT FROM AUTHOR]

A sharp-interface algorithm developed for immersed smoothed finite element method (Sharp-ISFEM) is proposed for fluid–structure interaction (FSI) problems. In Sharp-ISFEM, a line normal approach is used for unstructured meshes to reconstruct the solutions near interface. Advanced smoothed finite element models describe the finite deformation of immersed solid structures. Well-developed characteristic-based split method is employed to simulate the incompressible laminar flow. The coupling of fluid and solid is treated by the modified weak partitioned fictitious domain method with different time steps for two phases. To handle large-scale FSI problems, octree and neighbor-neighbor searching algorithms have been implemented. Meanwhile, parallelization has been implemented for the time-consuming parts of in-house codes. The effectiveness of proposed Sharp-ISFEM is validated by several benchmarking problems, including: fixed rigid body, flow over square cylinder; moving rigid body, flow induced by 2D hovering wing; large deformed solid, a beam with large deformation induced by flow; 3D deformable solid–fluid interaction, and lid-driven cavity flow with a rubber wall. Good agreements are shown in all test cases, comparing with existed experimental data and reference solutions. With the improvement of local velocity reconstruction, advanced searching algorithms and code parallelization, the proposed method has shown great promises for complex engineering flows with higher Reynolds number.A large-scale FSI problem of a hummingbird with flexible wing in hovering is finally simulated using more than one million nodes. [ABSTRACT FROM AUTHOR]

Occupant behaviour on air conditioning directly influences building energy consumption. Current building energy simulation typically assumes that occupants operate air conditioners ideally ignoring the stochastic characteristic of occupant behaviour, which leads to a large deviation of predicted energy performance from real consumption. This paper proposed a methodology framework for modelling occupants’ stochastic behaviour on air conditioning. This method combined measured data, statistical analysis and logistic regression to derive stochastic behaviour models that give the probability of when and above which temperature occupants may turn on air conditioning, at what temperature they may set and when they may turn off air conditioning. The behaviour models developed in this paper were further incorporated in widely used building simulation engine—EnergyPlus. The accuracy of the developed simulation model was validated against field measurement. Using this model, the cooling energy performance was simulated and compared with results from building energy standard based settings. The result shows that simulation using settings according to building energy standard over-predicts cooling load and total cooling energy requirements by 113% and 5.6 times respectively, which are very large discrepancies and may lead to a misunderstanding of energy savings potential of energy efficiency measures. The methodology developed in this paper has generality and can be extended and applied in other buildings for constructing behaviour models of air conditioning. The limitations of the current research as well as future research works were also discussed. [ABSTRACT FROM AUTHOR]

In order to improve the practical effect of environmental planning methods, this paper combines neural network artificial intelligence technology to study the environmental planning methods. Based on the idea of multi-layer DEM's stratum 3D modeling, this paper uses the spatial interpolation analysis in ArcGIS to fit the surface of the environmental data to obtain the surface layer of the stratum interface, and combine the geographic information system to construct the system frame structure. Moreover, based on neural network and artificial intelligence technology, this paper uses the prediction algorithm based on the comprehensive index and the BP neural network model to process and calculate the sample data, and conduct experimental analysis on the system of this paper through experimental research. The research results show that the environmental planning method based on neural network and artificial intelligence technology proposed in this paper has good results and can be applied to current environmental planning for auxiliary planning. • The practical effect of environmental planning methods. • Based on the idea of multi-layer DEM's stratum 3D modeling. • The spatial interpolation analysis in ArcGIS to fit the surface. • The stratum interface, and combine the geographic information. [ABSTRACT FROM AUTHOR]

Most of the current techniques for concrete bridge inspection are based on human visual interpretation, which often is dangerous and time-consuming. To address this problem, we introduce in this paper a newly developed vehicle-based robot inspection system that can automatically capture thousands of bottom surface images with a group of high-resolution industrial cameras, which are then stitched into a single composite image. However, traditional image stitching methods generally fail with large drift due to the great number (more than 2000) and sparse texture of linearly distributed images in sequence. Therefore, a novel image stitching method was developed for our robot inspection system, which combines both the 2D image point features and the 3D line features to reduce the drift. First, the bottom surface images are arranged into different strips based on their acquisition order and rough poses, and images in a single strip are divided into several groups. Then, the proposed image stitching method is performed in a bottom-up way, as follows: 1) the images within a single group initially are aligned via their point and line features; 2) the groups within a single strip are then stitched together via a homographic refinement procedure; 3) the strips are aligned into a single composite image that completely covers the bottom surface of the bridge; and 4) after all the stitching procedure are complete, a multi-band blending algorithm is applied to generate the mosaicked panorama as seamlessly as possible. The experimental results on a set of representative images acquired from the bottom surfaces of a real bridge demonstrate the capabilities and the limitations of the proposed approach. [ABSTRACT FROM AUTHOR]

We theoretically predict the existence of tunneling valley Hall effect and Nernst effect in the normal/strain/normal graphene junctions, where a strained graphene is sandwiched by two normal graphene electrodes. By applying an electric bias a pure transverse valley Hall current with longitudinal charge current is generated. If the system is driven by a temperature bias, a valley Nernst effect is observed, where a pure transverse valley current without charge current propagates. Furthermore, the transverse valley current can be modulated by the Fermi energy and crystallographic orientation. When the magnetic field is further considered, we obtain a fully valley-polarized current. It is expected these features may be helpful in the design of the controllable valleytronic devices. [ABSTRACT FROM AUTHOR]

The Ti 44.5 Ni 46.5- x Nb 9 Co x ( x  = 0.5, 1, 2, 4) alloys were designated to investigate the effect of Co content and annealing treatment on the precipitation behavior and mechanical properties. The formation of nanoscale precipitates was being reported here for the first time in the Ti-Ni-Nb alloys due to the Co addition. For the Ti 44.5 Ni 45.5 Nb 9 Co 1 and Ti 44.5 Ni 44.5 Nb 9 Co 2 alloys, homogeneous GP zones and precipitates were observed at the lower annealing temperature. Additionally, the yield strength was enhanced by the higher strain field produced by the nano coherent precipitates. The effect of precipitation strengthening was weakened because of coarsened and clustered precipitates as annealing temperature increased. As a result, the highest yield strength of 520 MPa and the highest recovery stress of 482 MPa could be realized in the Ti 44.5 Ni 44.5 Nb 9 Co 2 alloy annealed at 550 °C. [ABSTRACT FROM AUTHOR]

Ten new highly oxygenated lanostane triterpenoids, stereinones A–J ( 1 – 10 ), were isolated from the fruiting bodies of the basidiomycete Stereum sp. Compounds 3 and 4 are structurally characterized as intact lanostane-type triterpenoids containing unusual 1,2-diketone functionality at C-11 and C-12, while compound 10 is a 24-methylene-lanostane. The structures of these new compounds were established based on detailed 1D and 2D NMR spectroscopic analyses, along with quantum chemical NMR calculations. All isolates were evaluated for their in vitro cytotoxicities against five human tumor cell lines (including HL-60, A-549, SMMC-7721, MCF-7, and SW480 cell lines). Compound 4 showed moderate cytotoxic activities against tumor cell lines SMMC-7721 and SW480 with IC 50 values of 9.1 and 9.8 μM, respectively. [ABSTRACT FROM AUTHOR]

The elastic and electronic properties of a series of bialkali alanates M 2 M′AlH 6 (Na 2 LiAlH 6 , K 2 LiAlH 6 , K 2 NaAlH 6 ) have been investigated by first principles calculations. The calculated lattice parameters and decomposition enthalpies are in good agreement with the experimental and other available data. All M 2 M′AlH 6 hydrides are found to be mechanically stable and brittle. The elastic moduli, Vickers hardness and the Debye temperature follow the order of Na 2 LiAlH 6 > K 2 LiAlH 6 > K 2 NaAlH 6 . The calculated elastic anisotropy indexes A Z , A U , A E indicate that the M 2 M′AlH 6 hydrides exhibit obvious anisotropy and the sequence follows K 2 LiAlH 6 > K 2 NaAlH 6 > Na 2 LiAlH 6 . From the density of states, the crystal orbital Hamiltonian population, bonding charge density, electron localization function and the Bader charge analyses, it can be confirmed that the existence of polar covalent bonding between Al and H within the [AlH 6 ] 3 − units and ionic bonding between [AlH 6 ] 3 − units and M, M′. [ABSTRACT FROM AUTHOR]

The sintering behavior of plasma-sprayed yttria-stabilized zirconia (YSZ) coating over the delamination crack and its influence on YSZ cracking were investigated via gradient thermal cycling test and finite element model (FEM). The gradient thermal cycling test was performed at a peak surface temperature of 1150 °C with a duration of 240 s for each cycle. A three-dimensional model including delamination cracks with different lengths was employed to elaborate the temperature evolution characteristics in YSZ coating over the delamination cracks. The temperature over the delamination crack increases linearly with the crack propagation, which continuously promotes the sintering of YSZ coating in the region. As a result, the YSZ coating over the delamination crack sinters dramatically despite of the low temperature exposure. Meanwhile, the temperature distribution difference in YSZ coating induces an nonuniform sintering along both free surface and thickness of YSZ coating. Correspondingly, the maximum vertical crack driving force locates at the YSZ free surface over the delamination crack center, which makes the vertical cracks generate in this region and propagate to the interface of YSZ /bond coat with YSZ further sintering. The vertical crack promotes the delamination crack propagation via accelerating the oxidation velocity of the bond coat. The influence of temperature rise on delamination crack propagation can be divided into two stages: the little contribution stage and the promotion stage. For the actual engine exposure to low temperature, the study of phase transformation of YSZ over the delamination crack is indeed needed because of an extended remarkable temperature rise period. [ABSTRACT FROM AUTHOR]

Y-stabilized ZrO 2 (YSZ) was one of the familiar high dielectric constant films used in InP field effect transistors. However, the structure and optical properties of YSZ film deposited on InP substrate were rarely reported. The band offsets in InP/YSZ hetero-junction was an important parameter, which had not been measured. In the work, YSZ films were deposited on InP substrates by sputtering. The optical properties and structures of YSZ films and InP/YSZ interface were characterized. X-ray photoelectron spectroscopy was used to measure the energy discontinuity in the valence band of the InP/YSZ hetero-structure. A value of 1.4 eV was obtained with In 3d5 as the reference energy level. With the band gap of 5.8 eV for YSZ and 1.3 eV for InP, this indicated a conduction band offset of 3.1 eV in the system. [ABSTRACT FROM AUTHOR]

Thermal stability and shape memory effect (SME) of Ni-Mn-Ga-based thin film were firstly investigated. The fluctuation scope of phase transformation temperatures did not exceed 2 °C during 100 thermal cycles. The maximum SME of 0.64% was quantitatively measured under 600 MPa applied stress. SME almost kept constant after 20 times thermal cycling deformation under 300 MPa applied stress. [ABSTRACT FROM AUTHOR]

Heat transfer through external walls plays a significant role in building energy saving. This paper tries to investigate the thermal and energy performance of a novel lightweight steel-bamboo wall structure. A testing residential building was constructed using the prefabricated steel-bamboo composite wall and field measurement was carried out to determine the heat transfer coefficient, time lag and decrement factor of the steel-bamboo wall. Numerical simulation was conducted in order to further evaluate its performance improvement compared to two commonly used wall structures in this climate region. The results show that the steel-bamboo wall has a high thermal performance with an improvement of U value by up to 26.1%–48.4%, indicating a lower heating demand compared to common wall structures in winter. Meanwhile, it has a high resistance to outdoor air temperature fluctuation with a low decrement factor of 0.022. The relatively low time lag (2 h) contributes to a lower indoor temperature during summer nighttime and thus reduces cooling energy demand. The improvement of total energy performance reaches 27.1%–40.9%, indicating a great potential of applications of this steel-bamboo wall in residential buildings in hot summer and cold winter zone. However, the main drawback of the steel-bamboo structure is that its indoor thermal performance during the hottest hours in summer is poorer than conventional walls. [ABSTRACT FROM AUTHOR]

The control of solidification microstructure is critical to successful laser processing of single-crystal (SX) nickel-base superalloys and a practical tool for the microstructural control is processing–microstructure maps. However, the maps presented in literature do not consider the effects of powder feeding during laser additive manufacturing (LAM) of SX superalloys. This paper therefore presents a simple and feasible strategy to deal with the effects of powder feeding and to extend the combined numerical model used to calculate processing–microstructure maps. A characteristic ratio of epitaxial SX growth was defined to quantitatively compare the final solidification microstructure. Resulting processing–microstructure maps can estimate the influence of most processing variables, especially powder feeding rate, on the extent of epitaxial SX growth and the position of columnar-to-equiaxed transition. Using the processing parameters selected according to these processing–microstructure maps, a multi-layer SX deposit with fine dendrites was successfully fabricated by LAM. This successful SX LAM indicates that these new processing–microstructure maps involving powder feeding are reliable and useful because they can determine proper processing windows for LAM of SX superalloys and further advance the understanding of the processing–microstructure relationship in powder-feeding LAM process. [ABSTRACT FROM AUTHOR]

Sirtiun 5 (SIRT5) is a NAD+-dependent protein lysine deacylase. It is emerging as a promising target for the development of drugs to treat cancer and metabolism-related diseases. In this study, we screened 5000 compounds and identified a hit compound 14 bearing a pyrazolone functional group as a novel SIRT5-selective inhibitor. Structure-based optimization of 14 resulted in compound 47 with an IC 50 value of 0.21 ± 0.02 μM and a 100-fold improved potency. Compound 47 showed substantial selectivity for SIRT5 over SIRT1-3 and SIRT6. Biochemical studies suggest that 47 does not occupy the NAD + -binding pocket and acts as a substrate-competitive inhibitor. The identified potent and selective SIRT5 inhibitors allow further studies as research tools and therapeutic agents. [Display omitted] • Hit compound 14 bearing a pyrazolone skeleton was identified as a SIRT5 inhibitor. • Extensive SAR studies guided by molecular docking were conducted. • Compound 47 showed a 100-fold increased potency as compared to the original hit. [ABSTRACT FROM AUTHOR]

In this paper, we propose a generic framework for globally consistent alignment of images captured from approximately planar scenes via topology analysis, capable of resisting the perspective distortion meanwhile preserving the local alignment accuracy. Firstly, to estimate the topological relations of images efficiently, we search for a main chain connecting all images over a fast built similarity table of image pairs (mainly for the unordered image sequence), along which the potential overlapping pairs are incrementally detected according to the gradually recovered geometric positions and orientations. Secondly, all the sequential images are organized as a spanning tree through applying a graph algorithm on the topological graph, so as to find the optimal reference image which minimizes the total number of error propagation. Thirdly, the global alignment under topology analysis is performed in the strategy that images are initially aligned by groups via the affine model, followed by the homography refinement under the anti-perspective constraint, which manages to keep the optimal balance between aligning precision and global consistency. Finally, experimental results on two challenging aerial image sets illustrate the superiority of the proposed approach. [ABSTRACT FROM AUTHOR]

Experimental process optimization is essential to obtain reliable processing conditions prior to performing actual laser additive manufacturing (LAM) of single-crystal (SX) nickel-base superalloys. The influence of processing parameters on deposited productivity and epitaxial SX growth in powder-feeding LAM process was systematically investigated by the orthogonal experiment (OE) method, a statistical experiment design method. This method can rapidly and economically estimate the effect of each processing parameter by a small number of experiments. Resulting relationship between the processing variables and each of deposited productivity and microstructure formation contributes to the selection of detailed processing conditions to balance the factors crucial to successful SX LAM, which means that appropriate adjustment of the processing parameters during actual SX LAM is easy to be performed. On the basis of the analyses of the OE results, a combination of relatively high power, low scanning velocity and moderate powder feeding rate is beneficial to both deposited productivity and epitaxial SX growth during powder-feeding LAM, and allows the preparation of good multilayer SX deposits with fine dendrites. [ABSTRACT FROM AUTHOR]

This paper introduces a new system for reconstructing 3D scenes from Line Segments (LS) on images. A new LS matching algorithm and a novel 3D LS reconstruction algorithm are incorporated into the system. Two coplanar cues that indicates image LSs are coplanar in physical (3D) space are extensively exploited in both algorithms: (1) adjacent image LSs are coplanar in space in a high possibility; (2) the projections of coplanar 3D LSs in two images are related by the same planar homography. Based on these two cues, we efficiently match LSs from two images firstly in pairs through matching the V-junctions formed by adjacent LSs, and secondly in individuals by exploiting local homographies. We extract for each V-junction a scale and affine invariant local region to match V-junctions from two images. The local homographies estimated from V-junction matches are used to match LSs in individuals. To get 3D LSs from the obtained LS matches, we propose to first estimate space planes from clustered LS matches and then back-project image LSs onto the space planes. Markov Random Field (MRF) is introduced to help more reliable LS match clustering. Experiments shows our LS matching algorithm significantly improves the efficiency of state-of-the-art methods while achieves comparable matching performance, and our 3D LS reconstruction algorithm generates more complete and detailed 3D scene models using much fewer images. [ABSTRACT FROM AUTHOR]

The influence of rapid thermal annealing temperature on the microstructure, martensitic transformation and mechanical properties of Ni 55.2 Mn 24.7 Ga 19.9 Gd 0.2 thin films was investigated. It was shown that as-deposited film displayed a coexistence of amorphous and austenite nano-crystals. When the annealing temperature was above 450 °C, Ni 55.2 Mn 24.7 Ga 19.9 Gd 0.2 thin films possessed seven-layered modulated martensite structure. With annealing temperature increased from 450 °C to 750 °C, the average grain size of annealed films increased from 126 to 596 nm and the transformation temperature also increased gradually. Fracture strain of 6.1% and tensile strength of 636 MPa were obtained for the Ni 55.2 Mn 24.7 Ga 19.9 Gd 0.2 thin film annealed at 550 °C. [ABSTRACT FROM AUTHOR]

The solidification path of single-crystal nickel-base superalloys containing minor carbon was investigated under various laser rapid directional solidification (LRDS) conditions. By controlling the solidification rate, LRDS processing can provide the evidence whether some diffusion-controlled phase transformations occur because such transformations will be suppressed under high cooling rates. Results show that the solidification path and final solidification microstructure depend upon the cooling rate; the microstructure without γ-γ′ eutectic can be obtained as long as the cooling rate is high enough. A peritectic transformation in carbon-containing single-crystal superalloys was first experimentally verified by controlling the cooling rate during LRDS processing. [ABSTRACT FROM AUTHOR]

Primary dendritic arm spacing (PDAS) is an important microstructure feature in the nickel-base single-crystal (SX) superalloys by laser rapid directional solidification (LRDS). A combined numerical model was developed in this paper to investigate the influence of laser processing parameters on the PDAS. This model consists of (1) the theoretical PDAS models which relate PDAS to the solidification conditions and (2) the heat-flux calculations of laser processing which provide the solidification conditions as a function of the processing parameters. It is therefore able to immediately relate the PDAS to the processing parameters and obtain corresponding processing–microstructure maps. To verify the predicted accuracy, the PDAS values calculated by different theoretical models were compared with those produced under different processing conditions. Results show that the PDAS firstly decreases and then increases at a lower laser power whereas it decreases with increasing scanning velocity at a higher laser power, leading to nose-shape contour lines. The predicted accuracy depends on appropriate selections of material thermo-physical properties. These processing–microstructure maps can accurately capture the trends of the PDAS variation with the processing parameters and contribute to the control and optimization of dendritic microstructure while determining relevant processing windows for controlled SX laser processing. [ABSTRACT FROM AUTHOR]

The reinforcement potential of reactive liquid crystals or reactive mesogens (RMs) in electrospun fibers was investigated through the blending of two types of RMs (RM257 and RM82) with two types of thermoplastics; polyamide 6 (PA6) and poly(methyl methacrylate) (PMMA). Polymer/RM blends were electrospun from solution into nanofibers followed by UV-radiation induced photo-polymerization in order to cross-link the RMs. The phase behaviour of the polymer/RM blends was investigated using optical microscopy and differential scanning calorimetry (DSC). Mechanical tests of the electrospun nanofibers showed the biggest improvement in mechanical properties for the PA6/RM257 system containing 33 wt% RMs, with a 20% increase in tensile strength and 150% increase in Young’s modulus compared to pure PA6 nanofibers. The work potentially provides a new route towards designed nanofibers with oriented microstructures, ultimately leading to a methodology for creating high performance electrospun nanofibers. [ABSTRACT FROM AUTHOR]

The microsegregation in single-crystal nickel-base superalloys, which may result in many undesired precipitated phases, can be effectively reduced by rapid solidification. A new microsegregation model for rapid solidification multicomponent alloys was developed in this paper to predict the microsegregation in the single-crystal superalloys of laser rapid directional solidification and study the influence of processing parameters on the microsegregation behavior. To verify the predicted accuracy of the present model, the concentration profiles and microsegregation ranges under different processing conditions were examined and compared with those calculated by different models. Compared with previous models, this multicomponent model not only has definite physical meaning but also takes nonequilibrium solidification and dendritic tip undercooling into account. Therefore, it is suitable for a wide range of solidification conditions and can obtain better predicted results for complex multicomponent alloys. Moreover, although the microsegregation behavior depends primarily on the solidification velocity, a high temperature gradient also contributes to reducing the microsegregation. Consequently, the microsegregation can be effectively controlled by using a set of processing parameters that can obtain high temperature gradient and solidification velocity. Such a model contributes to the control of the microsegregation while determining relevant processing windows for the preparation of superalloy components using a controlled single-crystal laser processing. [ABSTRACT FROM AUTHOR]

The prediction of building energy consumption is indispensable to reduce energy consumption, improve energy efficiency and achieve carbon neutrality. The stochastic adjustment of shading has an important impact on energy consumption due to the uncertainty in the use of window shades in common office buildings. This study is based on a stochastic shading building model established in the previous study and uses time, temperature, solar radiation, and shading coefficient as input variables for predicting shading related energy uncertainty. Firstly machine learning algorithm is used for modeling, then Shapley Value Method is applied to refine the model variables, and finally, the model is optimized by hyperparameter optimization. The resulting model can perform uncertainty prediction of building energy consumption under stochastic shading adjustment. The results indicate that the Gaussian process regression is suitable for the prediction, and the final model prediction accuracies of R2 are all above 0.9, which can be used in practical applications. This study is the first to address the uncertainty prediction of building energy consumption under stochastic shading adjustment using machine learning methods without the use of energy simulation tools. • Energy uncertainty fluctuation under stochastic shading adjustment was predicted. • Machine learning method was used for prediction instead of physical energy models. • Shapley value and hyperparameter optimization are used to reduce prediction errors. [ABSTRACT FROM AUTHOR]

The stray-grain formation and epitaxy loss at the substrate during laser surface remelting of single-crystal nickel-base superalloys, which immediately lead to the break of the single-crystal growth, were investigated by means of modeling and experiments. Results indicate that the stray-grain formation and epitaxy loss at the substrate are attributed to the increased trend of the formation of equiaxed grains resulting from the composition segregation at the substrate interdendritic region. Accordingly, a solution treatment for the substrates prior to laser processing can effectively avoid the SG formation and epitaxy loss, which reveals a basic precondition, homogenized solution treatment of substrates, for successful single-crystal laser processing. [ABSTRACT FROM AUTHOR]

This paper presents a hierarchical method for matching line segments from two images. Line segments are matched first in groups and then in individuals. While matched in groups, the line segments lying adjacently are intersected to form junctions. At the places of the junctions, the structures are constructed called Line–Junction–Line (LJL), which consists of two adjacent line segments and their intersecting junction. To reliably deal with the possible scale change between the two images to be matched, we propose to describe LJLs by a robust descriptor in the multi-scale pyramids of images constructed from two original images. By evaluating the description vector distances of LJLs from the two images, some candidate LJL matches are obtained, which are then refined and expanded by an effective match-propagation strategy. The line segments used to construct LJLs are matched when the LJLs they formed are matched. For those left unmatched line segments, we match them in individuals by utilizing the local homographies estimated from their neighboring matched LJLs. Experiments demonstrate the superiorities of the proposed method to the state-of-the-art methods for its robustness in more difficult situations, the larger amounts of correct matches, and the higher accuracy in most cases. [ABSTRACT FROM AUTHOR]

Nanocrystalline Ni 55.2 Mn 24.7 Ga 19.9 Gd 0.2 high temperature shape memory thin films had been prepared by the DC magnetron sputtering followed by rapid thermal annealing (RTA). Surface morphology, crystal structure, martensitic transformation behavior and shape memory effect (SME) were systematically investigated. The results showed that as-deposited film displayed a coexistence of amorphous and nanocrystal, while the annealed film was a single phase of seven-layered modulated martensite structure with the grain size about 200–500 nm at room temperature. The annealed film showed one step reversible martensitic transformation with martensitic transformation start temperature of 283 °C. Adjacent lamellar variants exhibited a (202) type Ι twin relationship and well coherent interlamellar interfaces. The annealed Ni 55.2 Mn 24.7 Ga 19.9 Gd 0.2 thin film displayed a stable SME above 200 °C, which could be used in high temperature field as micro-electro-mechanical-system (MEMS) devices. [ABSTRACT FROM AUTHOR]

While mosaicking images, especially captured from the scenes of large depth differences with respective to cameras at varying locations, the detection of seamlines within overlap regions is a key issue for creating seamless and pleasant image mosaics. In this paper, we propose a novel algorithm to efficiently detect optimal seamlines for mosaicking aerial images captured from different viewpoints and for mosaicking street-view panoramic images without a precisely common center in a graph cuts energy minimization framework. To effectively ensure that the seamlines are optimally detected in the laterally continuous regions with high image similarity and low object dislocation to magnificently conceal the parallax between images, we fuse the information of image color, gradient magnitude, and texture complexity into the data and smooth energy terms in graph cuts. Different from the traditional frame-to-frame optimization for sequentially detecting seamlines for mosaicking multiple images, our method applies a novel multi-frame joint optimization strategy to find seamlines within multi-overlapped images at one time. In addition, we propose simple but effective strategies to semi-automatically guide the seamlines by exploiting simple human–computer interaction strongly constraining the image regions that the seamlines will or won’t pass through, which is often ignored by many existing seamline detection methods. Experimental results on a large set of aerial, oblique and street-view panoramic images show that the proposed method is capable of creating high-quality seamlines for multiple image mosaicking, while not crossing majority of visually obvious foreground objects and most of overlap regions with low image similarity to effectively conceal the image parallax at different extents. [ABSTRACT FROM AUTHOR]

The electrical resistivity, structure, and composition and work function of ZnO thin films deposited by sputtering and post-treated with He plasma were studied. First, the treating effects of ZnO films by He, Ar and H 2 plasmas were compared. The electrical resistivity depended on the treated type of plasmas, the treated powers and times, and the thickness of film. The Ar plasma has the highest ion moment energy to disrupt the Zn-O bonding during treatment. The injection of H in ZnO can also act as the shallow donors to decrease the resistivity besides by desorption of weakly bonded oxygen species. The H 2 and He plasmas have the etching effects on the surface of ZnO films at higher power and time. For the ZnO films before and after optimized He plasma treating, the electrical resistivity decreased from 10 4 to 7.0 × 10 −3 Ω cm, the carrier concentration increased from 7.0 × 10 15 to 1.8 × 10 2 ° cm −3 , and the interstitial Zn and O vacancy deficiencies increased from 29.1 to 58.7% and 52.1 to 71.4%, and the work functions reduced from 8.5 to 7.6 eV, but with no significant change of crystal structure. [ABSTRACT FROM AUTHOR]

Electrospun co-polyimide BPDA (3, 3′, 4, 4′-Biphenyltetracarboxylic dianhydride)/PDA (p-Phenylenediamine)/ODA (4, 4′-oxydianiline) nanofiber reinforced flexible composites were manufactured by impregnating these high performance nanofibers with styrene-butadiene-styrene (SBS) triblock copolymer solutions. The off-axis Young's moduli and tensile strengths of the unidirectional composites were measured and evaluated. It was found that the experimental off-axis data were in close agreement with the predicted data. Subsequently, the influence of nanofiber misalignment on the performance of the unidirectional composites was investigated and it was shown that better alignment leads to higher values of Young's modulus. Rule of mixtures was for the first time applied to electrospun nanofiber reinforced composites to back-calculate the Young's modulus of individual nanofibers. A Young's modulus of 58.9 GPa was found for these co-polyimide nanofibers, similar to commercial high-performance fibers like Kevlar 29. [ABSTRACT FROM AUTHOR]