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We report that continuous MOF films with highly controlled thickness (from 44 to 5100 nm) can be deposited over length scales greater than 80 centimeters by a facile, fast, and cost-effective spray-coating method. Such success relies on our discovery of unprecedented perfectly dispersed colloidal solutions consisting of amorphous MOF nanoparticles, which we adopted as precursors that readily converted to the crystalline films upon low-temperature in situ heating. The colloidal solutions allow for the fabrication of compact and uniform MOF films on a great deal of substrates such as fluorine-doped tin oxide, glass, SiO2 , Al2 O3 , Si, Cu, and even flexible polycarbonate, widening their technological applications where substrates are essential. Despite the present work focuses on the fabrication of uniform cobalt-(2-methylimidazole)2 and zinc-(2-methylimidazole)2 films, our findings mark a great possibility in producing other high-quality MOF thin films on a large scale.

Self‐assembly generated materials induced by an external magnetic field have attracted considerable interest following the development of nanodevices. However, the fabrication of macroscopic and anisotropic magnetic films at the nanoscale remains a challenge. Here, anisotropic magnetic films are successfully prepared using a solution‐based nanowire assembly strategy under a magnetic field. The assembly process is manipulated by changing the thickness of silica shell coated on the surface of magnetic nanowires. The anisotropic magnetic films show highly anisotropic magnetization under different angles of magnetic field and better magnetization properties than that of disordered magnetic films. The well‐defined nanowire arrays enable magnetization anisotropic property which may be useful in the magnetic energy conversion technologies and biomedical sciences which lie far beyond those achievable with traditional magnetic materials., Bioinspired! The anisotropic magnetic field in the brain of homing animals has inspired us to develop a self‐assembly strategy to fabricate ordered and highly anisotropic magnetic nanowires films. The anisotropic magnetic films showed prominent anisotropic magnetization useful to facilitate the development of magnetic energy conversion technologies.

Over the past decades, nanomaterials have been proven to have superior properties, because of their unique structural features differentiating from atoms and bulk materials, and their large-scale p...

Assembling various nanowires together, enabling the assemblies with tailored optical, electrical, and multifunctional properties, represents a promising technology for next generation multifunctional electronics. Here we demonstrate a novel multicolor electrochromic device by coassembling W18O49 and V2O5 nanowires using solution-based Langmuir-Blodgett technique. The transparent W18O49 nanowire film became orange with the increasing addition of V2O5 nanowires and the film underwent a dynamic color change (orange, green, and gray) on application of different electrochemical biases of 2, 0, and -0.5 V (vs Ag/AgCl). Both the transmittance and color of the device can be easily controlled by manipulating the layers of coassembled nanowires and the ratios between the two nanowires. On the basis of this approach, different patterns can be easily fabricated with the addition of corresponding masks, and the solid electrochromic device is assembled, suggesting its significant potentials in smart windows and multicolor electrochromic displays.

Ultrathin necklace-like Ag2Te nanowires with a diameter of 10 nm and a length of several micrometers are fabricated by a simple solution-based process at low temperature, and the Ag2Te nanowire films are fabricated by a Langmuir–Blodgett technique. A reversible structural phase transition of the nanowire films obtained can be observed, and in addition is also reflected by the electrical properties.

In the past two decades, the field of surface-enhanced Raman scattering (SERS) has flourished and many rational strategies have been reported for the successful construction of SERS substrates. However, it still lacks the mass-production and programmability for practical applications with arbitrary configurations, and it is highly desirable to develop SERS substrates with strong signal enhancement, large-scale surface area, easy fabrication and low cost. Herein, we demonstrate a large-area fabrication (1.5 m × 5 m) of low-cost (18.8 dollars per square meter), highly sensitive, flexible and transparent SERS substrate by a simple solution process. The high sensitivity of SERS substrate using 3,3′-diethylthiatricarbocyanine iodide (DTTCI) as probe molecules is strongly dependent on the density and diameter of gold nanoparticles (NPs) on the surface of nylon mesh with the best enhancement factor (EF) of 9.17 × 1010 and the SERS detection limit of DTTCI molecules is as low as 10-14 M which shows no obvious degradation even after 10,000 cycles of fatigue test, high temperature (above than 160 °C) and acid-alkali treatment, indicating their excellent stability for the performance in all climates.

The configuration, slipping and rotation of self-interstitial atoms cluster along crystal orientation with different sizes in a tungsten are investigated systematically with molecular dynamic...

Summary: Designing large-area flexible transparent smart windows for high-efficiency indoor fine particulate matter (PM2.5) capture is important to guarantee safe indoor environments. In this article, we demonstrate that large-area fabrication of flexible transparent Ag-nylon mesh can be performed not only to turn the indoor light illumination intensity as thermochromic smart windows after uniformly coating with thermochromic dye but also to purify indoor air as high-efficiency PM2.5 filter. It takes only about $15.03 and 20 min to fabricate 7.5-m2 Ag-nylon flexible transparent windows without any modification with a sheet resistance of as low as 8.87 Ω sq−1 and optical transmittance of 86.05%. As an excellent PM filter (can be recycled after PM filtration), the removal efficiency is as high as 99.65% and the processing speed is high, which can reduce the PM2.5 density from heavily polluted (248 μg·m−3, purple alert) to good (32.9 μg·m−3, green statement) in 50 s. : Environmental Nanotechnology; Materials Processing; Electrical Materials Subject Areas: Environmental Nanotechnology, Materials Processing, Electrical Materials

The interaction of H2O molecules with the CeO2(1 1 1) and (1 1 0) surfaces with the supported Au and Pd single atom catalysts (Au/CeO2 and Pd/CeO2) has been studied based on the first-principles calculation. It is found that H2O energetically prefers to be dissociative adsorption on the Pd/CeO2(1 1 0), Au/CeO2(1 1 1) and Au/CeO2(1 1 0) surfaces with the adsorption energies of 1.71, 1.91 and 1.40 eV, respectively, while both molecular (1.06 eV) and dissociative adsorption (1.15 eV) may coexist for H2O on the Pd/CeO2(1 1 1) surface. H2O dissociative adsorption is much more exothermic on the Pd/CeO2(1 1 0) surface than on the Pd/CeO2(1 1 1) surface, while the opposite behavior has been observed for H2O adsorption on the Au/CeO2 surface. The relevant mechanism has been discussed based on the electronic structure analysis. In addition, we have made a comparison between the Pd(Au)/CeO2 surfaces and the pristine CeO2 surfaces in terms of the H2O adsorption exothermicity and the kinetic barrier of H2O dissociation, which indicate that the supported metal single atoms can greatly enhance the chemical activity of CeO2 toward H2O. Our study would give useful insights into the reactions involving H2O catalyzed by the CeO2-supported Pd and Au nanocatalysts, when the Pd and Au are existing in the form of single atoms.

Using the density functional theory calculations with the PBE exchange–correlation energy functional, we have studied the magnetic property and electronic properties such as binding energy, embedding energy, charge transfer, ionization potential and electron affinity of the NinGe (n = 19–29) neutral and ionic clusters. The addition of Ge atom can decrease the magnetic moments of Nin clusters except Ni28 and Ni 28 +/− . The charge is transferred from Ge atom to Ni clusters. And the local maxima value has appeared at Ni25Ge cluster. Both the calculated ionization potential and electron affinity exhibit an oscillating behavior as the cluster size increases.

Using the first-principles calculations, we study the structural, electronic and magnetic properties of the neutral and ionic Nin-1X (n = 19–23; X = Na–Cl) clusters. The calculations are performed using the density functional theory with the PBE exchange–correlation energy functional. The results reveal that the most stable structures of Nin-1X (X = Na, Mg, Al, Si) clusters are all similar to those of corresponding Nin clusters, while there are substantial structural deformations of Nin-1X (X = P, S, Cl) clusters. From the optimized results, a systematic analysis is carried out to obtain the relative stability, charge transfer, magnetic moments, density of states, electron affinity and ionization potential of Nin-1X clusters. Our findings also suggest how to change the stability, electronic and magnetic properties by doping different atoms in Ni clusters.

Structural, electronic and magnetic properties of the neutral and ionic Nin−1X (X = C, Si, Ge, Sn, Pb; n = 19–23) clusters have been investigated using the density functional theory calculations with the PBE exchange–correlation energy functional. The calculations have shown that for the most stable structures of all Nin−1X clusters, only Si atom prefers to locate in the center position, while for the other atoms, the impurity usually adopts the surface position. Based on the most stable Nin−1X clusters, the properties including binding energy per atom, embedding energy, charge transfer, ionization potentials, electron affinities and especially magnetic properties have been discussed.

Organic conjugated porous polymers, triazine-Ph-CPP and triazine-Th-CPP, are synthesized and characterized. Without further addition of co-catalysts, triazine-Ph-CPP exhibits a HER of 16 287 μmol g−1 h−1 and an apparent quantum yield of 61.5% at 365 nm, which demonstrates that the dibenzo[b,d]thiophene sulfone and 1,3,5-triazine based polymer is a unique prototype of a highly efficient hydrogen evolution photocatalyst.

Nanowire devices have attracted considerable attention because of their unique structure and novel properties, and have opened up significant development opportunities. However, not many studies have focused on their stability and durability under practical conditions, which limits the rapid development of real applications. Herein, we systematically investigate three different treatments,polymer coating, inert atmosphere protection, and thickness-induced self-protection, to protect the tellurium nanowire devices from oxidation when exposed to open air. The degree of oxidation was monitored by examining changes in the valence states of tellurium element and in the morphology of the nanowires. After the protective treatments, the tellurium nanowire devices showed improved stability and remained stable even after 800 days of storage. This work highlights the importance of investigating the stability of nanowire devices, especially for their practical applications.

To achieve both fast response and structural integrity during the repeating volume changes are the most significant challenges for thermoresponsive hydrogels. In this work, AuNRs/PNIPAM composite hydrogel with fast thermal/optical response and structural integrity is facilely prepared by electrospinning and following a curing treatment. By combining the photothermal property of AuNRs and thermal-responsive effect of PNIPAM, the composite hydrogel shows fast thermal/photoresponse, high heating rate, and high structural integrity with fierce size change. When laser irradiation begins, the temperature of the film increases from room temperature to 34.5 °C in 1 s and will further increase even to 60 °C in 5 s. Both the porous structure of the hydrogel and the assemble effect of AuNRs within the PNIPAM fibers facilitate the fast responsibility. Furthermore, to take advantage of this fibrous hydrogel adequately, one novel kind of thermal/photocontrolled switch based on the composite hydrogel is prepared, which exhibits fast responsivity and high stability even under acidic or basic conditions.

Using the density functional theory calculations with the PBE exchange–correlation energy functional, we have studied the low-energy structures and electronic properties of Ni–Al alloy clusters for adsorbing or doping an aluminum atom to Nin (n = 13, 19, 23, 26, 29 and 55) clusters. The most stable structures of NinAl are viewed as adding an Al atom at the hollow triangle and rhombus site of the icosahedron (n = 13, 55) and double-icosahedron (n = 19, 23, 26 and 29) structures, respectively. For Nin−1Al, it can be seen that an Al atom gradually moves from surface (n = 13, 19, 23 and 26) to the interior site (n = 29, 55) in the most stable structures. The electronic properties of the Ni–Al alloy clusters including binding energies, magnetic properties, charge transfer and density of states have also been studied.

Polycarborane, as a kind of boron carbide polymeric precursor, was synthesized by hydroboration reaction with styrene, divinylbenzene as the carbon resource and borane as the boron resource in this work. The polymer precursor which had good solubility and film-forming ability was soluble in most organic solvents. Furthermore, polycarborane was used to fabricate hollow polymer microspheres by emulsion technique. The compact boron carbide ceramic hollow microspheres were prepared by ceramization of the polymer microspheres. Ceramic microspheres with diameters ranging from 1 to 1.5 mm and shell thicknesses from 15 to 30 μm were easily prepared by changing emulsion composition and curing conditions. Micrographs of SEM showed that the hollow microspheres had smooth surface and good sphericity. These boron carbide ceramic hollow microspheres are of significant importance for application in the field of neutron moderator in nuclear reactors, power generation in deep space flight, etc.

In this study, we present a room-temperature environmentally friendly solution process to optimize the performance of the flexible transparent electrodes by co-assembling Ag nanowires and CaCO3 nanowires, and then etching CaCO3 nanowires away, leaving Ag nanowire networks with controllable optical transparency and electrical conductivity. The obtained Ag nanowire flexible transparent electrodes exhibit an averaged transmittance of up to 90% when the sheet resistance is 70 Ω sq−1 which shows no degradation even after 2000 cycles of fatigue test, indicating their excellent mechanical flexibility and stability.

We introduce the concept of electrophobic interaction, analogous to hydrophobic interaction, for describing the behavior of impurity atoms in a metal, a “solvent of electrons”. We demonstrate that there exists a form of electrophobic interaction between impurities with closed electron shell structure, which governs their dissolution behavior in a metal. Using He, Be and Ar as examples, we predict by first-principles calculations that the electrophobic interaction drives He, Be or Ar to form a close-packed cluster with a clustering energy that follows a universal power-law scaling with the number of atoms (N) dissolved in a free electron gas, as well as W or Al lattice, as Ec ∝ (N2/3−N). This new concept unifies the explanation for a series of experimental observations of close-packed inert-gas bubble formation in metals, and significantly advances our fundamental understanding and capacity to predict the solute behavior of impurities in metals, a useful contribution to be considered in future material design of metals for nuclear, metallurgical, and energy applications.

Conventional mesoporous materials-based transducers generally possess symmetrical geometries and are unable to easily distinguish two or more components in mixtures and reject the interferences. In this issue, Zhao et al. develop Janus mesostructures to realize a simultaneous multivariable gases sensor using solvent evaporation-induced self-assembly (EISA) with subsequent surface modifications.

The shape-controlled silver nanostructures have been widely used for template synthesis of metal nanostructures with desired morphologies and compositions for specific applications by galvanic replacement reaction, while the silver is sacrificed as oxidized to silver ion and abandoned as by-products. In view of the broad application prospect of the obtained metal nanostructures, the cost and environment problems after the template reactions should be taken into account for the large scale production in the future. To solve this problem, we conceptually demonstrate that the wasted AgCl generated from the template reactions can be easily recycled for the synthesis of valuable Ag nanowires. As representative examples, the average recovery of silver can be about 69.8%–84.6% after the template synthesis of Au/Pt nanostructures. The resynthesized Ag nanowires show uniform size distribution and excellent physical and chemical properties for the fabrication of transparent electrode and template synthesis.

Rechargeable Li batteries based on group VIA element cathodes, such as tellurium, are emerging due to their capability to provide equivalent theoretical volumetric capacity density to O and S, as well as an improved activity to react with Li. Herein, bifunctional and elastic carbon nanotube (CNT) aerogel is fabricated to combine with Te nanowires, yielding two types of binder/collector-free Te cathodes to assemble Li-Te batteries. The CNTs with high electronic conductivity and hollow porous structure enable stable electric contact and fast transportation of Li+, while trapping Te and Li2Te in its network, triggering fast and stable Li-Te electrochemistry. Both cathodes are also provided with fine compressibility, helping to buffer their volume changes during lithiation/delithiation and improving electrode integrity. Both cathodes deliver high specific capacity, fine cycling stability, and favorable high-rate capability, proving their competence in building high-energy rechargeable Li-ion batteries.

The fabrication of nanowire (NW)-based flexible electronics including wearable energy storage devices, flexible displays, electrical sensors, and health monitors has received great attention both in fundamental research and market requirements in our daily lives. Other than a disordered state after synthesis, NWs with designed and hierarchical structures would not only optimize the intrinsic performance, but also create new physical and chemical properties, and integration of individual NWs into well-defined structures over large areas is one of the most promising strategies to optimize the performance of NW-based flexible electronics. Here, the recent developments and achievements made in the field of flexible electronics composed of integrated NW structures are presented. The different assembly strategies for the construction of 1D, 2D, and 3D NW assemblies, especially the NW coassembly process for 2D NW assemblies, are comprehensively discussed. The improvements of different NW assemblies on flexible electronics structure and performance are described in detail to elucidate the advantages of well-defined NW assemblies. Finally, a short summary and outlook for future challenges and perspectives in this field are presented.

The structural and electronic properties, such as adsorption energy, magnetic property, and charge-transferring process of Nin (n = 1–6) clusters interacting with pristine, strained and defective graphene were investigated by using the density functional theory calculations with the Perdew–Burke–Ernzerhof exchange-correlation energy functional. By introducing strain and defects, the stability of the cluster-graphene system was improved significantly. The magnetic moments increased monotonically for Nin clusters on pristine and strained graphene while exhibited an oscillating behaviour for defective graphene. On the other hand, more charges being transferred from Nin clusters to defective graphene were observed compared with pristine and strained graphene.

In this study, polysulfone (PSf) nano-hybrid membranes have been successfully fabricated by loading modified multi-walled carbon nanotubes (MWCNTs) as the dispersed phase using the phase inversion method. MWCNTs were chemically functionalized with polyethylene glycol (PEG) to achieve better dispersion in the polymer matrix. PEG-g-CNTs were confirmed by ATR-FTIR and XPS spectroscopy. The hybrid membranes showed better hydrophilicity, higher pure water flux and more excellent antifouling properties. The results demonstrated that the membrane containing 1.5 wt% PEG-g-MWCNTs showed the lowest contact angle (53.9°) and the highest water flux (71.26 L m−2 h−1) which was significantly higher than that of the pure PSf membrane and MWCNTs/PSf membrane. In BSA filtration analysis, the modified MWCNTs led to significant improvement of the fouling recovery ratio (FRR) and dramatic reduction of the adsorption amount of BSA. In addition, membranes exhibited excellent tensile strength after the addition of PEG-g-MWCNTs.

Manipulating nanowire assembly could help the design of hierarchical structures with unique functionalities. Herein, we first report a facile solution-based process under ambient conditions for co-assembling two kinds of nanowires which have suitable composition and functionalities, such as Ag and Te nanowires, for the fabrication of flexible transparent electrodes. Then Te nanowires can be etched away easily, leaving Ag nanowire networks with controllable pitch. By manipulating the assembly of Ag and Te nanowires, we can precisely tailor and balance the optical transmittance and the conductivity of the resulting flexible transparent electrodes. The network of Ag nanowires which have tunable pitch forms a flexible transparent conducting electrode with an averaged transmission of up to 97.3 % and sheet resistances as low as 2.7 Ω/sq under optimized conditions. The work provides a new way for tailoring the properties of nanowire-based devices.

In order to clear the timeliness issues of metal magnetic memory signal value after unloading, we conduct some static tension experiments on some specimens in materials of KMN, which is commonly used in centrifugal compressors? Furthermore, we analyze the specimen, which is prefabricated artificial defects, on the surface normal magnetic field strength decay law with EMS-2003, the intelligent magnetic memory tester. The results show that: the surface magnetic field signal value is reduced by time after unloading, in other words it has certain timeliness.

Flexible hetero-nanowire electronics: A simple solution process has been developed for the first time to fabricate macroscopic flexible, ordered Au-Te hetero-nanowire film electronics with tunable resistance from MΩ to Ω at room temperature (see the Figure). Nanowire films with an electrical conductivity as low as 10,000 S cm(-1) and a sheet resistance of 15Ω sq(-1) can generate reliable interconnections for light-emitting diode (LED) arrays. The Au-Te hetero-nanowire films remain conductive after bending 6000 times with a maximum bending radius of 2.0 mm without any obvious degradation.

Ordered W18O49 nanowire thin films were fabricated by Langmuir-Blodgett (LB) technique in the presence of poly(vinyl pyrrolidone) coating. The well-organized monolayer of W18O49 nanowires with periodic structures can be readily used as electrochromic sensors, showing reversibly switched electrochromic properties between the negative and positive voltage. Moreover, the electrochromism properties of the W18O49 nanowire films exhibit significant relationship with their thickness. The coloration/bleaching time was around 2 s for the W18O49 nanowire monolayer, which is much faster than the traditional tungsten oxide nanostructures. Moreover, the nanowire devices display excellent stability when color switching continues, which may provide a versatile and promising platform for electrochromism device, smart windows, and other applications.

High nitrogen Fe-18Cr-12Mn-3Mo-xN austenitic stainless steels were prepared by mechanical alloying and powder metallurgical pressing-sintering techniques. The microstructures, nitrogen contents and sintering properties of the milled powders and sintered bodies had been also investigated. The results show that high nitrogen and nearly spherical composite powders with good compressibility can be obtained by high-energy vibration ball milling and high temperature nitriding. It is also found that the sintering temperature has a significant effect on the density and the nitrogen content of sintered specimens, and the optimal sintering temperature are determined to be 1250°C, at which a favorable combination of the relative density as high as 97.1% and the final nitrogen content of 0.79wt% in sintered specimens can be obtained. The sintered bodies mainly consist of γ-austenite, α-ferrite and the lamellar Cr2N phase. After solution-annealing at 1150°C for 1.5h followed by water-quenching, high nitrogen austenitic stainless steels reveal a fully austenitic structure.

A new method called mixed Lagrangian and Eulerian method (MiLE method) was used to simulate the thermomechanical behavior during continuous casting process of steel YF45MnV. The simulation results are basically in agreement with the measured data. The delaying period at the beginning of solidification is about 0.1 in square root of solidification time which is agreement with the data in literatures, and shell thickness increases in linear relation to square root of solidification time. The bloom surface temperature decreases gradually as the casting proceeds. The effective stress in the corner is much larger than that in the mid-face. The corner area is the dangerous zone of cracking. The effects of mold flux break temperature on the air gap and hot tearing indicator were also modeled. The model predicts that the bloom surface temperature increases with the increase of the mold flux break temperature, but the heat flux decreases with the increase of the mold flux break temperature. The hot tearing indicator is much smaller when the mold flux break temperature is higher.

Converting biomass into fuel is becoming increasingly important owing to the desirability of finding substitutes for fossil fuels and to the need to address the problem of global warming. Cellulose, one of the main constituents of biomass, is the most abundant bio-renewable material on the planet. Considerable effort has been devoted to the hydrolysis of cellulose in order to convert it into fuel. In this paper, both two-dimensional electrode electrochemical degradation of cellulose and the use of biological degradation of cellulose were investigated, which provides a detailed study of cellulose activity and stability in various ionic liquids. In the two-dimensional electrode reaction system, after 5 hours at the voltage of 8 V under the conditions of electrolysis, the degradation of cellulose reached 43.7%, BOD5/COD also significantly improved with biological treatment to the combination of electrochemical techniques. As the result, HEMA is a promising, novel, green medium for performing cellulose hydrolysis reactions to convert biomass into bio-fuels.

A general chemical transformation process for synthesis of more than 45 kinds of one-dimensional metal chalcogenide nanostructure., One-dimensional metal chalcogenide nanostructures are important candidates for many technological applications such as photovoltaic and thermoelectric devices. However, the design and synthesis of one-dimensional metal chalcogenide nanostructured materials with controllable components and properties remain a challenge. We report a general chemical transformation process for the synthesis of more than 45 kinds of one-dimensional alloyed/hybrid metal chalcogenide nanostructures inherited from mother template TexSey@Se core-shell nanowires with tunable compositions. As many as nine types of monometal chalcogenide alloy nanowires (including AgSeTe, HgSeTe, CuSeTe, BiSeTe, PbSeTe, CdSeTe, SbSeTe, NiSeTe, and CoSeTe) can be synthesized. Alloyed and hybrid nanowires integrated with two or more alloyed metal chalcogenide phases can also be prepared. The compositions of all of these metal chalcogenide nanowires are tunable within a wide range. This protocol provides a new general route for the controllable synthesis of a new generation of one-dimensional metal chalcogenide nanostructures.

The secondary dendritic arm spacing (SDAS) of free cutting steel 38MnVS during continuous casting process was simulated based on a Mixed Lagrangian and Eulerian Method (MiLE Method) and SDAS model. The simulation results are basically in agreement with measured ones. The effect of composition, superheat and casting speed on SDAS are studied, and the relationship between SDAS and interdendritic segregation is discussed. The results show that SDAS increases with increasing carbon and silicon content, and decreases with increasing manganese and sulfur content. The increase of superheat and casting speed also makes SDAS increase. The permeability of columnar mushy zone which is parallel to the primary dendritic arms is calculated based on Carman-Kozeny relationship, and the increase of SDAS makes the permeability increase, which exacerbates interdendritic segregation of columnar crystal zone.

The finite element model of the reinforced beam was established. The results were obtained, such as the structural distortion diagram, the cleavage process diagram, the deflection contour map, the stress contour map to the X axle and the equivalent stress map. The result of the simulation shows that the established reinforced beam bring plastic strain and appear crack under the uniform pressure.

High nitrogen nanostructured Fe-17Cr-11Mn-3Mo stainless steel powders were produced by high energy ball milling under a nitrogen atmosphere. It was found with increasing the milling time, the nitrogen contents of the powder mixtures increase linearly up to 1.98 wt pct after 96h, and a linear regression equation, WN = 0.19357 + 0.01887t , has been further established. In addition, with the increased milling time, the crystallite sizes and particle sizes of the powders decrease continuously, the lattice strains and sphericity of the powders increase gradually. After milling 60h, the high nitrogen nanocrystalline stainless steel powders with a fine particle size range of 5~10μm, excellent sphericity and uniform components can be obtained, whose crystallite size is about 5.0nm and lattice strain is about 1.0%. The powders milled for 60h was compacted using spark plasma sintering process at different temperatures. It is found that a fully austenitic high nitrogen stainless steel with almost full densification can be obtained by SPS at 1000°C, whose nitrogen content is 0.82 wt pct.

The 3D-microstructure in 9SMn28 free-cutting steel under water cooling condition was simulated based on the finite element–cellular automaton method with convection and porosity, and the simulated results are consistent with that of the experiment. The casting of 9SMn28 alloy is a stepwise solidification mode under water cooling condition. Convection is mainly made of buoyancy-driven flows and feeding flows in perpendicular direction of the solid–liquid interface. Convection is the reason of shaggy on free surface; it can decrease pipe shrinkage and columnar grain zone. Flow field plays an importance role in even temperature field and irregulation porosity morphology. The simulated result of pipe shrinkage is consistent with that of this experiment; the simulated result of porosity is identical with that of this experiment basically.

Since 1952 when Branemark first reported osseointegration of titanium (Ti) with bone, many academic and industrial research activities have endeavored to improve the efficacy of Ti or Ti alloy (Ti6Al4V) by modifying the chemistry, topography and design of the implant surface. Strong bonding between implant and host tissue minimize the micromovements that promote fibrous tissue formation at the implant interface that may lead to implant failure. Surface design include lateral holes perpendicular to the implant axis, grooves, variations of spacings between ridges, etc. Physico-mechanical means of surface modification is by grit-blasting with various abrasives (alumina, silica, apatitic abrasive), laser ablation, spark discharge, etc. Chemical modifications include: acid etching, treatment with alkali, treatment with fluoride, coating with titanium or with calcium phosphate (by plasma spray, electromagnetic sputtering, electrochemical deposition). A review of studies on Ti or Ti alloy implants with different surfaces showed the following methods to enhance osseointegration and greater bone formation: (1) grit-blasting with apatitic abrasive; (2) acid-etching with mixed acids; (3) adjusting plasma-spray parameter to get a higher HA/ACP ratio in the coating; (4) employing electrochemical deposition (with pulse modulation) or precipitation to obtain thin coating with homogeneous composition; and/or (5) Ftreatment.

The implementation of an optical function into supercapacitors is an innovative approach to make energy storage devices smarter and to meet the requirements of smart electronics. Here, it is reported for the first time that nickel-cobalt hydroxide on reduced graphene oxide can be utilized for flexible electrochromic supercapacitors. A new and straightforward one-step electrochemical deposition process is introduced that is capable of simultaneously reducing GO and depositing amorphous Co(1-x)Ni(x)(OH)2 on the rGO. It is shown that the rGO nanosheets are homogeneously coated with metal hydroxide and are vertically stacked. No high temperature processes are used so that flexible polymer-based substrates can be coated. The synthesized self-stacked rGO-Co(1-x)Ni(x)(OH)2 nanosheet material exhibits pseudocapacitive charge storage behavior with excellent rate capability, high Columbic efficiency, and nondiffusion limited behavior. It is shown that the electrochemical behavior of the Ni(OH)2 can be modulated, by simultaneously depositing nickel and cobalt hydroxide, into broad oxidization and reduction bands. Further, the material exhibits electrochromic property and can switch between a bleached and transparent state. Literature comparison reveals that the performance characteristics of the rGO-Co(1-x)Ni(x)(OH)2 nanosheet material, in terms of gravimetric capacitance, areal capacitance, and long-term cycling stability, are among the highest reported values of supercapacitors with electrochromic property.

Single-crystal PbTiO 3 (PT) nanorods have been synthesized by annealing PT nanocrystals in NaCl flux. The as-prepared PT nanorods are straight, with diameters of 50–80 nm and lengths of a few micrometers. The nanorods are in tetragonal crystal structure with lattice constants a = b = 3.926 A and c = 3.963 A. All the Raman modes of the PT nanorods have been indexed and the soften behavior of mode E(1TO) was observed, implying the weakening of ferroelectricity. The formation of the nanorods has also been discussed.

In this study, we report a facile bio-inspired method for large-scale preparation of highly dispersed Ag nanoparticles (NPs) on the surface of flexible reduced graphene oxide (rGO) paper with using dopamine (DA) both as a reductant and a surface modifier. Through the self-polymerization of dopamine, free-standing GO paper can be simultaneously reduced and modified with following in situ growth of monolayer Ag NPs on such a substrate. The spherical Ag NPs with an average diameter of 80 nm have a narrow size distribution and tunable cover density. Such a flexible rGO/Ag hybrid paper presents enhanced antibacterial activity against E. coli and a high active and sensitive SERS response toward Rhodamine 6G (R6G) molecules. The detection signals can be obtained while the R6G concentration is as low as to 10(-8) M. This work provides a simple strategy for large-scale fabrication of monolayer Ag NPs on flexible rGO paper as a portable antibacterial substrate and a potential SERS substrate for molecular detection applications.

Assembly of nanowires into ordered macroscopic structures with new functionalities has been a recent focus. In this Letter, we report a new route for ordering hydrophilic Ag nanowires with high aspect ratio by flowing through a glass capillary. The present glass capillary with well-defined silver nanowire films inside can serve as a portable and reusable substrate for surface-enhanced Raman spectroscopy (SERS), which may provide a versatile and promising platform for detecting mixture pollutions. By controlling the flow parameters of nanowire suspensions, initially random Ag nanowires can be aligned to form nanowire arrays with tunable density, forming cambered nanowire films adhered onto the inner wall of the capillary. Compared with the planar ordered Ag nanowire films by the Langmuir-Blodgett (LB) technique, the cambered nanowire films show better SERS performance.

We have observed a new kind of photoinduced conical light scattering with quasi-periodic oscillation for the first time. The effect may be related to temporal-spatial changes in the photorefractive phase grating recorded by the incident laser beam along (or near) the - c direction and its reflected beam.