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The current work reports a unique bio-inspired synthesis of orange derived pectin modified magnetite nanoparticles (Fe3O4 NPs). Pectin is a naturally occurring biopolymer containing plethora of polar organofunctions which are exploited in the toxic reagent free modification of biocompatible magnetic NPs and also towards the stabilization of NPs by preventing them from agglomeration. The physicochemical properties of the as-prepared bio-nanocomposite (Fe3O4@Pectin) was analytically investigated through SEM, EDX, TEM, VSM and XRD. The anti-gastrointestinal system cancers and cytotoxic potentials of synthesized NPs against cancer cell lines were assessed. The anti-gastrointestinal system cancers potentials of the NPscould significantly remove (HT-29, HCT 116, Ramos.2G6.4C10, HCT-8 (Colorectal cancer)), (Capan-2, AsPC-1, CFPAC-1, HPAF-II (Pancreatic cancer)), (GC1436, GC1401, AGS, and GC1415 (Gastric cancer)) cell lines by MTT assay. The corresponding IC50 were found as 13, 8, 16, 15, 11, 12, 15, 15, 23, 36, 30, and 23 μg/mL against HT-29, HCT 116, Ramos.2G6.4C10, HCT-8, Capan-2, AsPC-1, CFPAC-1, HPAF-II, GC1436, GC1401, AGS, and GC1415 cancer cell lines. Furthermore, the antioxidant capacity of Fe3O4@Pectin NPswas determined by DPPH method which displayeda significant activity as per IC50 value. It is believed that the antioxidant effects play a significant role in the considerable anti-colorectal, pancreatic and gastric cancerseffects.

In the last few decades, smart windows made from VO2-based thermochromic films have attracted extensive attention, but their actual commercial applications are limited by low luminous transmittance (Tlum), low solar modulation ability (ΔTsol), high phase transition temperature (Tc), and poor durability. In this study, glass/HfO2/VO2/HfO2 tri-layer films were designed and deposited on glass substrates by pulse laser deposition. Crystal structures, surface morphology, surface roughness, electrical properties, and optical properties of as-prepared sandwich structure films were analyzed. Results showed that both HfO2 buffer layer and antireflection layer (ARL) were monoclinic phase and grew along the (020) and (−111) crystal planes, respectively. HfO2 buffer layer not only reduced Tc of VO2 film by about 20 °C, but also played an important role in regulating crystal quality and surface morphology of VO2 films. More importantly, by covering films with HfO2 ARL, Tlum and ΔTsol of VO2 film were greatly improved. In particular, when the thicknesses of HfO2 buffer layer and ARL were 80 nm and 120 nm, the obtained HfO2/VO2/HfO2 tri-layer film reached a balance between high Tlum (∼47.2%), high ΔTsol (∼9.1%) and low Tc (∼49.1 °C). In addition, after 216 h of boiling water treatment, Tlum and ΔTsol of HfO2/VO2/HfO2 film covered with 120 nm thick ARL still remained at 49.3% and 7.0%, showing excellent durability. This research provides a new strategy for designing VO2-based smart windows with high performance and good durability.

Using silicon nanoporous pillar array (Si-NPA) as a template, a prototype humidity sensor was fabricated by growing NH2-MIL-125(Ti) on it through a simple hydrothermal method. With the relative humidity (RH) changed from 11 to 75% measured at 20 Hz, a capacitance response over 5397% was gained. The response time was 70 s and the recovery time was only 6 s. The highest hysteresis was evaluated to be ~ 1.9% at 54% RH. These phenomena are attributed to the channel network induced by Si-NPA, while the high humidity sensitivity may be ascribed to the increase in the given surface area due to its unique nanostructure.

High-performance vanadium dioxide (VO2) thin films with high luminous transmittance and solar modulation ability were successfully fabricated on ZrxOy/glass substrate by pulsed laser deposition. By controlling the growth temperature of the buffer layer, the stoichiometry and crystal structure of ZrxOy buffer layer can be converted from cubic Zr2O phase to monoclinic ZrO2 phase. Through such a transformation, the luminous transmittance (Tlum), solar modulation ability (ΔTsol), the transition temperature and the width of thermal hysteresis loop have been tuned without diminishing the thermochromic property. It is found that the insertion of ZrO2 layer results in a remarkable enhancement of the luminous transmittance and the solar modulation ability when compared to single-layer VO2 film. The findings in the present work may provide some new strategies for the commercialization of VO2 films in the field of smart energy-efficient windows.

(Zr47Cu44Al9)100−xNbx (x = 0, 1, 2, 3, and 5 at.%) bulk metallic glasses (BMGs) were prepared by copper mould casting. The influence of Nb addition on glass-forming ability (GFA), thermal stability and mechanical properties of ZrCuAl alloys was studied. The GFA of Zr47Cu44Al9 BMGs is enhanced obviously after the addition of Nb. The critical size of completely amorphous sample increases from 4 mm for Zr47Cu44Al9 to 10 mm for (Zr47Cu44Al9)98Nb2 alloy. The average activation energy of crystallization is 505 kJ/mol for (Zr47Cu44Al9)98Nb2 BMG, which is larger than that of Zr47Cu44Al9 BMG with 443 kJ/mol. The fracture strength and plasticity are sensitive to the Nb content. (Zr47Cu44Al9)98Nb2 BMG exhibits high fracture strength of 2397 MPa and prominent plastic strain of 13.2%, and multiple shear bands with high density were observed. Furthermore, the possible mechanisms involved in obtaining high GFA and large plasticity were explored.

Vanadium dioxide (VO2) with reversible metal–insulator transition (MIT) is a promising energy-saving material for next-generation smart windows and infrared devices. However, the specific applications are largely limited by controllable preparation with different polymorphs on common glass substrates. Herein, VO2 thin films were prepared on transparent amorphous glass substrates by inserting TiO2 buffer layers using pulsed laser deposition (PLD) technique. The results showed that B-VO2 film would be formed on the amorphous glass substrate at 400 °C. While after inserting TiO2 buffer layer, pure M-VO2 films with clear phase transition properties were obtained. Based on the analysis of X-ray Diffraction (XRD) and Energy Dispersive Spectrometer (EDS) characterization, the crystalline transformation was attributed to the template effect of TiO2 layer and Ti ions diffusion. The characteristics of VO2/TiO2/glass thin films were closely associated with the thickness of TiO2 buffer layer. With 60 nm TiO2 buffer layer, the VO2/TiO2/glass film showed the sharpest resistance change with more than 2.5-order of magnitude across the MIT, and the T-vis value is as high as 53% with the ΔTsol up to 5.2%. Our current results demonstrated the importance of TiO2 buffer layer to the formation of M-VO2 film on amorphous glass substrate, which was very meaningful for the production of energy efficient smart windows in the future.

Monoclinic vanadium dioxide (M-VO2) is a kind of typical thermal phase change materials, but its relatively high phase transition temperature (68 °C) and low solar modulation efficiency greatly hinder the applications as energy materials. In this work, well-crystalline M-VO2 were prepared by pulsed laser deposition (PLD) under the adjustable oxygen pressure range. By fine adjusting the low oxygen pressure (0.1–0.9 Pa), VO2 maintain the monoclinic crystal and excellent photoelectrical properties, even if oxygen deficiency and other defects exist. Results indicate that the phase-transition temperature (Tc) decreases with the decrease of oxygen pressures while the solar modulation efficiency (ΔTsol) increases with the decrease of oxygen pressures. Moreover, the M-VO2 thin films prepared with 0.3 Pa oxygen pressure showed the best photoelectric performance, in which the sheet resistance changes up to three orders of magnitude, the phase-transition temperature is 61 °C and the ΔTsol is as high as 8.3%. This work has demonstrated the role of moderate oxygen defects in optimizing the photoelectric properties of M-VO2, also provided a feasibility study on how to deposit pure M-VO2 by PLD.

(Zr47Cu44Al9)100−xSix (x = 0, 0.5, 1.5 and 2.5 at%) thin-film metallic glasses (TFMGs) were deposited at glass substrate by pulsed laser deposition. The influence of Si content and substrate temperature on the microstructure, optical and electrical properties was investigated. After adding Si in the Zr47Cu44Al9 system, the transmittance of the films enhances obviously, especially in the near-infrared region. The resistivity increases and becomes more sensitive to the temperature due to Si addition. With increasing substrate temperatures from room temperature to 430 °C, (Zr47Cu44Al9)98.5Si1.5 films display fully amorphous structure. Appropriate substrate temperature drastically decreases the resistivity of films without degrading the transmittance. (Zr47Cu44Al9)98.5Si1.5 TFMG deposited at 330 °C exhibits the visible transmittance of 49.38%, the infrared transmittance of 80.27% and the resistivity of 7.62 mΩ cm, which are useful properties for their potential applications in infrared technology with the high requirement of radiation resistance and corrosion resistance.

Zr50Cu50, Zr47Cu44Al9, Zr46.3Cu43.4Al8.3Nb2 and Zr41.2Ti13.8Cu17.5Ni5Be22.5 thin film metallic glasses (TFMGs) were prepared by pulsed laser deposition (PLD) on glass substrates at room temperature. The effect of thickness on the electrical and optical properties of the Zr-based TFMGs was investigated. It was found that the resistivity of the Zr-based TFMGs basically decreased as the thickness varied from 10 nm to 40 nm. Interestingly, while the transmittance in the visible region decreased significantly with the increase of thickness, the transmittance in the near-infrared range still remained at a high level of larger than 80%. Through the characterization of electrical properties, the high transmittance of the Zr-based TFMGs in the near-infrared range was attributed to their rather low carrier concentration. Our findings provided the possibility for TFMGs to be used as transparent electrodes in the field of near infrared sensors and solar cells. Keywords: Thin film metallic glass, Zr-based alloys, Transmittance, Near infrared

Vanadium dioxide (VO2) thin films with pure Monoclinic phase could be transformed from B-phase by inserting TiO2 buffer layers on transparent amorphous glass substrates at the low temperature of 400 °C. This crystalline transformation might be ascribed to oxygen-deficient environment induced by the TiO2 buffer layer and the template effect of TiO2 layer for M-VO2 phase. The simplicity in phase regulation of the present method and the superior optical and electrical properties of the films may allow its wide applications in thermo-opto-electro sensing devices. Keywords: Vanadium dioxide, TiO2 buffer layers, Photoelectric properties

Surface morphological control of the metal-insulator transition behaviors of VO 2 epitaxial thin films is achieved by annealing substrates of (0001)-Al 2 O 3 single crystals. The well-defined terraces of the (0001)-Al 2 O 3 substrates are formed by annealing in air at 1200 °C. Correspondingly, the surface roughness dramatically decreases in the VO 2 epitaxial thin films on the annealed substrates, compared with that on the unannealed substrates. The order of magnitude of the resistivity change ratio (~ 10 2 ) of annealed samples across the metal-insulator transition (MIT) decreases by a factor of one, compared with that (~ 10 3 ) in unannealed samples. This result is ascribed to grain size effect in the VO 2 epitaxial thin films. Moreover, the MIT temperature is reduced in the annealed samples with various thickness, compared with the unannealed ones. A reduction of 14.4 K of the MIT temperature is observed in the thinnest VO 2 films on the annealed substrates, compared with the unannealed samples. This behavior results from a compressive strain along the V-V atom chains in the annealed samples, which modifies the orbital occupancy of the V 4+ ions. While increasing the film thickness, the MIT change ratio keeps on the order of magnitude 10 2 , and the MIT temperatures of the VO 2 films on the annealed substrates becomes closer and closer to those of the unannealed samples due to the weakened substrate effect. This work suggests a promising approach to decrease the MIT temperature and still maintain a moderate change ratio for the MIT, potentially enabling room-temperature electronic devices based on VO 2 thin films.

Novel AZO/Zr50Cu50/AZO tri-layer transparent conductive films with excellent transmittance in both visible and near infrared region were successfully prepared by pulsed laser deposition on glass substrates. The electrical and optical properties were investigated at various Zr50Cu50 thicknesses. As the AZO thickness was fixed at 50 nm and Zr50Cu50 thickness was varied between 1 and 18 nm, it was found that AZO (50 nm)/Zr50Cu50/AZO (50 nm) tri-layer films exhibited good conductivity and high transmittance in both visible and near infrared wavelength. Additionally, both the electrical and optical properties of AZO (50 nm)/Zr50Cu50 (2 nm)/AZO (50 nm) tri-layer films were found to be sensitive to the growth temperature. In this work, the lowest sheet resistance (43 Ω/□) and relatively high transmittance (∼80%) in the range of 400–2000 nm were achieved while the growth temperature was 350 °C. Furthermore, the AZO (50 nm)/Zr50Cu50 (2 nm)/AZO (50 nm) thin film deposited at 350 °C exhibits the highest figure of merit of 1.42 × 10−3 Ω−1, indicating that the multilayer is promising for coated glasses and thin film solar cells. Keywords: Transparent conductive oxide, AZO, Zr50Cu50, Electrical and optical properties, Visible and near infrared transmittance

The SnO2/VO2/SnO2 (SVS) multilayer films were prepared using pulsed laser deposition and were characterized by X-ray diffraction, Raman spectroscopy, scanning electron microscopy, Hall Effect Measurement System, double beam spectrophotometer and contact angle measurements. The results showed that SVS multilayer films with excellent thermochromic properties were obtained by adjusting the preparation temperature of the SnO2 buffer layer and antireflection layer. When the preparation temperature of the SnO2 layer was 320 °C, the phase transition amplitude (ΔR) of the VO2 film reached 354 times and both the phase transition temperature (Tc) and hysteresis loop width (ΔH) could be effectively reduced. Meanwhile, the SVS multilayer film had satisfactory luminous transmittance (50.2%) and solar modulation ability (15.3%), achieving the balance of optical properties. In addition, all the SVS multilayer films exhibited excellent hydrophobicity. Boiling water experiments show that the service life of SVS tri-layer film is twice that of SV bi-layer film. This work suggests that the SVS multilayer films are a good candidate for VO2-based smart windows.

Multi-walled carbon nanotubes (MWCNTs) with strong visible fluorescence were synthesized via oxidation and amination. A large number of oxygen-containing surface functional groups contributing to fluorescence emission have been found, and the novel structure of carbon nanoclusters with the diameter of 20–30 nm are formed at the tips of MWCNTs. The fluorescent MWCNTs exhibit distinct excitation-wavelength dependence and pH response. Furthermore, the temperature sensitivity of fluorescence has been described carefully. The fluorescence intensity first increases and then decreases upon increasing temperature, and the maximum emission is achieved when the functionalized MWCNTs are dried at 150 °C.

A series of Zr35−xTi30Cu7.5Be27.5Fex (x = 0–10) bulk metallic glasses are cast using water-cooled copper mold casting technique. The glass forming ability (GFA) and thermal stability of Zr35−xTi30Cu7.5Be27.5Fex alloys were studied by means of X-ray diffraction and differential scanning calorimetry. It was found that the Zr35−xTi30Cu7.5Be27.5Fex (x = 2, 3, 5 and 7, respectively) alloys could be cast into glassy cylindrical rods with a diameters up to 20 mm. However, higher Fe content (x = 10) deteriorates the GFA remarkably. The supercooled liquid region (ΔTx), γ parameter (defined as Tx/(Tg + Tl)) and the reduced glass transition temperature Trg (defined as Tg/Tl) are employed to evaluate the GFA in Zr35−xTi30Cu7.5Be27.5Fex (x = 0–10) alloys. The results showed that Trg was more effective in gauging the GFA of the Zr35−xTi30Cu7.5Be27.5Fex alloy systems than ΔTx and γ parameter. In addition, elastic constant (Poisson’s ratio) was also employed as a gauge to evaluate the glass forming ability in Zr35−xTi30Cu7.5Be27.5Fex alloys. Keywords: Zr-based alloys, Bulk metallic glasses, Glass forming ability, Thermal stability and elastic properties

For decades, the practical application of VO2-based smart windows is limited by its low luminous transmittance (Tlum) and solar modulation ability (ΔTsol). In this study, SnO2/VO2 thermochromic thin films were produced on amorphous glass substrates via pulsed laser deposition and were characterized by x-ray diffraction, scanning electron microscopy, atomic force microscopy, spectrophotometry, and resistance measurements. By adjusting the thickness of SnO2 buffer layer, not only the semiconductor-to-metal transition temperature of VO2 films can be effectively tuned, but also the Tlum and ΔTsol of VO2 films can be increased synchronously to 54.9% and 8.3%, respectively. It is shown that the grain size of VO2 films increases from ~15 nm to ~90 nm with the SnO2 buffer layer thicknesses increase from 25 nm to 125 nm, and consequently the electrical and optical properties of VO2 films are effectively improved. These can be attributed to the fact that SnO2 buffer layer can effectively control the grain size, surface roughness and optical band gap of VO2.The results suggest that the SnO2 buffer layer is very beneficial for the growth of high-quality VO2 films on glass substrates, which is of importance for the application of VO2 in energy-efficient smart windows.

Aluminum-doped ZnO (AZO) thin films with thin film metallic glass of Zr50Cu50 as buffer are prepared on glass substrates by the pulsed laser deposition. The influence of buffer thickness and substrate temperature on structural, optical, and electrical properties of AZO thin film are investigated. Increasing the thickness of buffer layer and substrate temperature can both promote the transformation of AZO from amorphous to crystalline structure, while they show (100) and (002) unique preferential orientations, respectively. After inserting Zr50Cu50 layer between the glass substrate and AZO film, the sheet resistance and visible transmittance decrease, but the infrared transmittance increases. With substrate temperature increasing from 25 °C to 520 °C, the sheet resistance of AZO(100 nm)/Zr50Cu50(4 nm) film first increases and then decreases, and the infrared transmittance is improved. The AZO(100 nm)/Zr50Cu50(4 nm) film deposited at a substrate temperature of 360 °C exhibits a low sheet resistance of 26.7 Ω/□, high transmittance of 82.1% in the visible light region, 81.6% in near-infrared region, and low surface roughness of 0.85 nm, which are useful properties for their potential applications in tandem solar cell and infrared technology.

Vanadium dioxide (VO2) with reversible metal&ndash, insulator transition (MIT) is one of the most promising energy-efficient materials. Especially for VO2-based smart windows, the visible transmittance and solar modulation ability are the most critical parameters. However, VO2 thin films that are directly deposited onto glass substrates are of poor crystallinity and MIT performance, limiting the practical applications of VO2/glass heterostructures. In this paper, a buffer layer of Cu50Zr50 was introduced to build a novel Zr-based thin film metallic glass (VO2/Cu50Zr50/glass) with multilayer structures for thermochromic applications. It is observed that the insertion of a Cu50Zr50 buffer layer with appropriate thickness results in a clear enhancement of crystalline quality and MIT performance in the VO2/Cu50Zr50/glass thin films, compared with the single-layer VO2/glass thin films. Moreover, the VO2/Cu50Zr50/glass bi-layer films exhibit better optical performance with enhanced solar modulation ability (&Delta, Tsol = 14.3%) and a high visible transmittance (Tvis = 52.3%), which represents a good balance between &Delta, Tsol and Tvis for smart window applications.

Mn-doped 3C-SiC film has been prepared onto the Si (1 1 1) substrate by employing a molecular beam epitaxy method. The experimental analysis establishes that the prepared sample shows the ferromagnetic property with a relatively high Curie temperature ( T c ) of 355 K, which is an exciting phenomenon on account of the scarceness in the SiC-based diluted magnetic semiconductor. The analysis derived from the X-ray diffraction and absorption spectroscopy patterns indicates that Mn atoms should react with Si atoms and then form Mn 4 Si 7 compounds. Combined with the theoretical simulation, it is speculated that a new alloy phase of Mn 4 Si 7 C x maybe appear, which should be responsible for the exceptionally high T c ferromagnetic behavior in the sample.

In this study, high-quality thermochromic vanadium dioxide (VO2) thin films were grown on ZrO2/glass by pulsed laser deposition and were investigated using X-ray diffraction (XRD), atomic force microscopy (AFM), double beam spectrophotometry and Hall Effect measurement system. Based on XRD results, it can be inferred that the crystal structure of ZrO2 buffer layer can be transformed between monoclinic and tetragonal structures with the increase of buffer layer thickness. Photoelectric performance tests showed that the introduction of ZrO2 buffer layer considerably reduced the phase transition temperature (Tc) and hysteresis loop width (ΔH) of the VO2 films and allowed the visible light transmittance (Tlum) and solar modulation ability (ΔTsol) of the films to be tuned effectively. Especially, when the thickness of the ZrO2 buffer layer was 50 nm, the Tc of the VO2 films reached the minimum value of 48 °C. When the ZrO2 buffer layer thickness increased to 125 nm, the sheet resistance change of the VO2 film attained two orders of magnitude, and their Tlum-90°C and ΔTsol were as high as 50.01% and 7.88%, respectively. These results showed that the ZrO2 buffer layer considerably affected the growth of VO2 films on amorphous glass substrates and was beneficial for the application of VO2 in energy-saving smart windows.

The effect of partial substitution of Al for Zr on the mechanical properties of Zr35-xTi30Cu7.5Be27.5Alx (x=0, 1, 1.5, 2, 2.5, 5, at%) bulk metallic glasses were studied by uniaxial compression test. The results showed that the compressive plasticity can be greatly improved from 0.95% (x=0) to 15.10% (x=1.5) and 3.45% (x=2) in Zr35Ti30Cu7.5Be27.5 bulk metallic glass. The fracture morphologies of the Zr35-xTi30Cu7.5Be27.5Alx bulk metallic glasses were characterized by means of scanning electron microscope (SEM). Transmission electron microscope (TEM) was employed to investigate the microstructures of the bulk metallic glasses containing different amounts of Al. It is found that the enhanced compressive plasticity could be attributed to the nanoscale heterogeneity in the bulk metallic glasses. The effect of Al addition on the microstructure and deformation behavior of the Zr-based bulk metallic glasses was discussed in terms of different critical shear stress (CSS).

Non-Gaussian triplet Markov random fields (TMF) model is suitable for dealing with multi-class segmentation of nonstationary and non-Gaussian synthetic aperture radar (SAR) images. However, the segmentation of SAR images utilizing this model still fails to resolve the misclassifications due to the inaccuracy of edge location. In this paper, we propose a new unsupervised multi-class segmentation algorithm by fusing the traditional energy function of TMF model with the principle of edge penalty. Through the introduction of the penalty function based on local edge strength information, the new energy function could prevent segment from smoothing across boundaries. Then we optimize the objective function that stems from the new energy function to obtain an iterative multi-region merging Bayesian maximum posterior mode (MPM) segmentation equation for the new segmentation algorithm. The effectiveness of the proposed algorithm is demonstrated by application to simulated data and real SAR images.

W f /Zr 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 bulk metallic glass composites were successfully prepared by a new inverted melt infiltrating method. The processing parameters were optimized by adjusting infiltrating temperature, infiltrating time and tungsten fibers’ volume fraction. The diameter of the tungsten fiber was found to have remarkable influence on compressive properties and fracture mode of the composites. The W f /Zr 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 bulk metallic glass composites reinforced with 50% volume fraction tungsten fiber (200 μm in diameter) exhibited the highest compressive strength and plastic strain up to 2146 MPa and 21.4%, respectively. Besides, the shear bands are found to get closer as the diameter of the tungsten fibers decreases.

Nano-scale alloy powders, with the average particle size of 50 nm and face-centered cubic structure, were prepared from NixCu1 − x (20%

Indentation and sliding friction of the as-cast, the relaxed and the crystallized Zr41Ti14Cu12.5Ni10Be22.5 bulk metallic glass (BMG) are investigated on nano — scale by nanoindentation. The depth, the width and the morphology of the scratches formed by the tip of the nanoindentor are different, which reflect the differences in structure, not only between the glassy and the crystallized states but also between the two glassy states, the as — cast and the relaxed. The coefficient of sliding friction of Zr — based BMG is increased with increasing the load, and it is maximal for annealed at 553K. Improved plastic deformability is found for the relaxed one.

Utilizing the Contourlet's advantages of multiscale, localization, directionality and anisotropy, a new SAR image segmentation algorithm based on hidden Markov tree (HMT) in Contourlet domain and dempster-shafer (D-S) theory of evidence is proposed in this paper. The algorithm extends the hidden Markov tree framework to Contourlet domain and fuses the clustering and persistence of Contourlet transform using HMT model and D-S theory, and then, we deduce the maximum a posterior (MAP) segmentation equation for the new fusion model. The algorithm is used to segment the real SAR images. Experimental results and analysis show that the proposed algorithm effectively reduces the influence of multiplicative speckle noise, improves the segmentation accuracy and provides a better visual quality for SAR images over the algorithms based on HMT-MRF in the wavelet domain, HMT and MRF in the Contourlet domain, respectively.

In view of the speckle noise in the SAR images, utilizing the Contourlet’s advantages of multiscale, localization, directionality and anisotropy, a new SAR image fusion segmentation algorithm based on the persistence and clustering in the Contourlet domain is proposed in this paper. The algorithm captures the persistence and clustering of the Contourlet transform, which is modeled by HMT and MRF, respectively. Then, these two models are fused by fuzzy logic, resulting in a Contourlet domain HMT-MRF fusion model. Finally, we deduce the maximum a posterior (MAP) segmentation equation for the new fusion model. The algorithm is used to segment the real SAR images. Experimental results and analysis indicate that the proposed algorithm effectively reduces the influence of multiplicative speckle noise, improves the segmentation accuracy and provides a better visual quality for SAR images over the algorithms based on HMT-MRF in the wavelet domain, HMT and MRF in the Contourlet domain, respectively.

A remarkable enhancement in room-temperature compressive deformability is realized by the minor-addition of 1.5 at.% Al in ZrTi-based bulk metallic glass. Two amorphous phases are observed by transmission electron microscopy in the Al-containing alloys and this explains the improvement of compression deformability The studies suggest that phase separation might occur in glass forming alloys with a negative enthalpy of mixing.

We investigated the electronic and optical properties of rock-salt aluminum nitride (AlN) using a first-principles method based on the plane-wave basis set. Analysis of the band structure shows that rock-salt aluminum nitride is a wide gap indirect semiconductor. The band gap is predicted to be 5.82 eV within the screened exchange local density approximation (sX-LDA) but to be reduced to 4.23 eV for strained rock-salt AlN corresponding to the experimental lattice constant 4.24 A. The optical properties including the dielectric function, reflectivity and energy-loss function are obtained and analyzed together with some features. The pressure coefficients of the indirect band gaps at the Γ, X and L points are also calculated, with the value of the smallest indirect band gap determined as 31 meV GPa−1.

The thermal stability and glass forming ability (GFA) of Zr35−xTi30Cu7.5Be27.5Agx (x = 0–10) alloys were studied by X-ray diffraction (XRD), differential scanning calorimetry (DSC) and ultrasonic techniques. We found that the addition of 1 at.% Ag can considerably enhance the GFA as indicated by an increase in the critical glass dimension from 15 mm in the Zr35Ti30Cu7.5Be27.5 alloy to 20 mm in the Zr34Ti30Cu7.5Be27.5Ag1 alloy. However, with the addition of more Ag the supercooled liquid region (ΔTx) and γ parameter (defined as Tx/Tg+Tl)) drastically decreased from 155 K and 0.436 to 76 K and 0.363, respectively, resulting in a decrease in the GFA. Additionally, the elastic constant (the ratio of shear modulus to bulk modulus or Poisson’s ratio) was also used as a gauge to evaluate the GFA in Zr35−xTi30Cu7.5Be27.5Agx alloys.