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In 2003, the excavation of the ancient site Baochuanchang Shipyard was carried out in Nanjing, China and this shipyard was believed to have been the workshop where the huge vessels of Zheng He's fleet were built and maintained. Several pieces of ancient putty were found here, and a small piece was sampled and analyzed in this paper to study its components and structure. The results of X-ray diffraction (XRD) showed that the putty was mainly composed of calcite (CaCO3), while pyrolysis-gas chromatography–mass spectrometry (Py-GC–MS) analysis indicated that tung oil was used in making the putty. In addition, plant fibers inside the putty were identified as jute by the means of polarizing microscope and scanning electron microscope (SEM) analysis. These findings confirmed the putty as the so-called chu-nam putty, which was a traditional sealing material used in ancient shipbuilding. Moreover, the surface morphology of the putty was obtained by SEM, and pore size distribution was measured by gas adsorption-desorption analysis. The analytical results suggested that the putty was quite compact, which could perform well in sealing huge wooden ships. This research revealed the shipbuilding skills of the Baochuanchang Shipyard. It may provide reference for studying Zheng He's vessels and make further a contribution to the conservation and restoration of ancient wooden ships of the Ming Dynasty.

Good thermal dispersion is essential for phosphors used in laser-lighting applications. Luminescent films naturally show better thermal dispersion than bulk phosphor because the distance to the supporting substrate is shorter, which facilitates heat dissipation. However, the underlying mechanism for luminescence saturation in films is still unclear. In addition, the synthesis of luminescent films always involves the use of carbon-rich organic materials, which can introduce both pores and carbon residues. Here, we present a facile sol–gel route to synthesize YAG:Ce thick films suitable for laser lighting applications. Inorganic aluminum hydroxides are used as gelling agent, which solves the carbon residue problem. A series of YAG:Ce films of different thicknesses was produced at relatively low temperature (975 °C). The YAG:Ce film shows no luminescence saturation under 4.1 W blue laser excitation. This means this approach represents a strong potential candidate for applications like automotive headlamps and many other devices.

The establishment of relevant model and solving an inverse random source problem are one of the main tools for analyzing mechanical properties of elastic materials. In this paper, we study an inverse random source problem for biharmonic equation in two dimension. Under some regularity assumptions on the structure of random source, the well-posedness of the forward problem is established. Moreover, based on the explicit solution of the forward problem, we can solve the corresponding inverse random source problem via two transformed integral equations. Numerical examples are presented to illustrate the validity and effectiveness of the proposed inversion method.

The development of quantum dot (QD) layers as color converters in phosphor-converted white laser diodes (pc-wLDs) is restricted due to their low stability under laser irradiation. The present study aims to develop a unique color converter geometry that enables the QD layer for high-power pc-wLDs. A red emitting QD layer was coated on a thermally stable and heat-conducting Al2O3-YAG:Ce composite ceramic (CC), which played dual role of yellow emitter and heat sink. Thus, thermal and flux pressure on the QD layer has been significantly mitigated. Under irradiation of a 5 W blue laser, the operating temperature for the QD layer was as low as ∼68 °C. Furthermore, the CC-QD color converter and a blue LD were combined to fabricate pc-wLDs, which have exhibited superior color properties in terms of a high color rendering index (∼80), a high wall-plug efficiency (∼91 lm/W). and tunable color temperatures. This indicates the suitability of QD layer for high-power and high color rendering laser lighting.

This article reviewed the current state of knowledge of glass aqueous corrosion mechanism with a focus on the contribution of modern characterization tools. A general consensus on the interaction of glass and aqueous medium was discussed. Particularly, the comparison between diffusion controlled corrosion and the interfacial-dissolution-and-reprecipitation mechanism is presented in order to identify the key issues or unknowns in the glass corrosion community. Electron microscope based techniques, chemical depth profiling techniques, and measurement of metrological properties were reviewed from contemporary studies of glass corrosion. In addition, newly-developed characterization techniques that being used in glass corrosion studies were reviewed and discussed.

Glass foams are being widely used as constructional materials due to their unique properties in thermal insulation, fire retardation, and shockwave absorption. However, the cost of energy consumption and processes in a conventional glass foam production limited the use of glass foams as sustainable materials. In this study, for the very first time, thermally tunable CaO–SnO2–P2O5–SiO2 glass foams with controllable pore size were presented as a novel category of melt-casting and float-manufacturable glasses. It was found that the pore size and thermal properties become tunable by manipulating the glass network, i.e., connecting linear chained Sn–P network with [SiO4] units. In addition, the unique combination of thermal properties and porous structure of CaO–SnO2–P2O5–SiO2 glasses shows potential in float glass foam production, which can produce glass foams sheet-by-sheet with less complexity in manufacturing processes.

The substitution of TiO2 with network modifiers (sodium, Na+ and calcium, Ca2+) within a bioactive glass series was investigated to synthesize amorphous scaffolds from the SiO2-CaO-Na2O-P2O5 glass system. Three glasses were formulated for this study, a control (BG) and two experimental formulations with 9 wt% TiO2 substituted for CaO (SC-1) and Na2O (SC-2) respectively. X-ray diffraction presented an amorphous pattern for BG and SC-1, with extensive crystallinity present in SC-2. Differential thermal analysis presented a higher Tg for SC-1 (559 °C) and SC-2 (627 °C) compared to BG (531 °C), however a greater distribution of Q-species was evident in SC-1 and SC-2, particularly in the Q1–Q2 regions as evidenced by MAS-NMR. Simulated Body Fluid (SBF) testing presented calcium phosphate (CaP) deposition on BG however no visible CaP layer was observed on the surface of SC-1 and SC-2. Ion release profiles exhibited a much slower Si release rate with respect to time for SC-1 and SC-2, which may be the limiting factor when tested in SBF. The addition of TiO2 to the glass stabilized the pH during SBF testing and significantly increased the hardness compared to the control BG. Scaffold fabrication was conducted with SC-1, and a porous amorphous structure was synthesized at 635 °C.

Magneto-optical glass is a category of optical materials. In this study, a series of Tb3+ doped Ga2O3–B2O3–SiO2–GeO2 (GBSG) glasses were prepared and studied. Through the density test, it was found that the structure of the magneto-optical glass tended to be dense. At the same time, the result of infrared spectrum shows that some changes happened to the structure of the sample with different Tb3 + concentration, resulting in the change of the density of the magneto-optical glass. The wavelength dependence of the Verdet constant has been studied. The results show that the rate of change of the Verdet constant at different wavelengths has nothing to do with the Tb3+ concentration, but only with the effective transition wavelength. The effective transition wavelength of the sample was calculated by the formula, and the source of the magneto-optical effect of the rare earth doped magneto-optical glass was confirmed.

In recent times, there have been rapid advances in the solid-state laser lighting technology. Due to the large amounts of heat accumulated from the high flux laser radiation, color conversion materials used in solid-state laser lighting devices should possess high durability, high thermal conductivity, and low thermal quenching. The aim of this study is to develop a thermally robust SiO2-YAG:Ce composite thick film (CTF) for high-power solid-state laser lighting applications. Commercial colloidal silica which was used as the source of SiO2, played the roles of an adhesive, a filler, and a protecting agent. Compared to the YAG:Ce powder, the CTF exhibits remarkable thermal stability (11.3% intensity drop at 200 °C) and durability (4.5% intensity drop after 1000 h, at 85 °C and 85% humidity). Furthermore, the effects of the substrate material and the thickness of the CTF on the laser lighting performance were investigated in terms of their thermal quenching and luminescence saturation behaviors, respectively. The CTF with a thickness of 50 μm on a sapphire substrate does not show luminescence saturation, despite a high-power density of incident radiation i.e. 20 W/mm2. These results demonstrate the potential applicability of the CTF in solid-state laser lighting devices.

The crystallization behavior and microstructure of a series of Dy 3 + /Tb 3 + doped aluminoborosilicate (ABS) magneto-optical glass was investigated using differential scanning calorimetry (DSC), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The apparent crystallization activation energy ( E g ) and the kinetic properties at the corresponding glass transition temperature ( T g ) were studied as a function of Dy 3 + /Tb 3 + concentration. The results showed that the glass matrix precipitated Al 3 Tb(BO 3 ) 4 and TbBO 3 crystals when subjected to heat treatment at 852.8 and 902.6 °C, respectively. The crystallization activation energy of these two crystalline phases (Al 3 Tb(BO 3 ) 4 and TbBO 3 ) was E p1 = 993.3 kJ/mol and E p2 = 544.97 kJ/mol, respectively. The average crystallization index was 0.5 and 0.8, respectively. By applying the Kissinger equation to the parameterized crystallization behavior, the calculated phase transition activation energy was determined to be 420.18 kJ/mol. The parameterized crystallization behavior of this particular ABS magneto-optical glass can be used to avoid the deterioration of magneto-optical properties due to the crystallization of glass matrix.

A well-decorated female coronet with some recognizable imprints of textile was excavated from the tomb of Empress Xiao of the Sui Dynasty in 2013. Mass spectrometry was employed to analyze the residual protein extracted from the soil underneath the coronet since no macroscopic form of textile existed. A dedicated method was applied and modified, and the results of mass spectrometry analysis and database search indicated that the residues should belong to ancient silk fibroin after excluding the possibilities of modern contamination. This research provided evidence for the use of silk in decorating the coronet of Empress Xiao, which provided reliable basis for its restoration work.

Additional file 1: Table S1. Questionnaire on the evaluation of virtual imaging restoration.

The present study highlights the synthesis of CuO–ZnO nanocomposite via facile hydrothermal method at 150 °C and autogenous pressure. The structural and textural features of prepared composite material was characterized by several characterization techniques such as X-ray powder diffraction, Fourier transform infrared spectroscopy, Scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The optimized prepared nanocomposite was utilized for photocatalytic degradation of aromatic Direct Blue 71 dye (DB71) under natural sunlight conditions. The catalytic activity results by CuO–ZnO nanocomposite were observed to be higher than the reagent-grade zinc oxide under visible light conditions. The response surface methodology protocol (RSM) with central composite design was optimized by different photodegradation operational parameters such as pH, dye concentration, catalyst amount, and reaction time. The optimized RSM results demonstrated that a quadratic polynomial model was found suitable to define the relation between the photocatalytic activity and operational parameters. Moreover, the observed high R 2 value (0.9786) confirms a strong evaluation of experimental data. To achieve maximum DB71 degradation, optimized condition was found at 177.13 min of contact time, 3.93 solution pH, and 24.34 mg/L of dye concentration with 1.85 g/L of catalyst dose The identical optimum conditions resulted maximum 89.58% DB71 degradation.

A series of copper (Cu)-containing glasses were synthesized and incorporated into a SiO2–ZnO–CaO–SrO–P2O5-based glass system. Additions of 6 and 12 mol% CuO retained the amorphous character, and glasses were processed to possess similar particle sizes and surface areas. Glass characterization using X-ray photoelectron spectroscopy and magic angle spinning nuclear magnetic resonance determined that the addition of 12 mol% CuO increased the fraction of Q4-speciation and the concentration of bridging oxygens. Each glass presented solubility profiles for the release of Si4+ (18–31 mg/L), Ca2+ (13–16 mg/L), Zn2+ (

In this study, germanium borosilicate magneto-optical (MO) glasses (GeO 2 -B 2 O 3 -SiO 2 -Ga 2 O 3 -xTb 2 O 3 ) doped with different concentrations of Tb 3+ ions were prepared by melt quenching technique. Structural, physical properties, optical properties and luminescent properties of obtained glasses were investigated in detail. Raman spectrum of the MO glasses shows that co-existence of trigonal [BO 3 ], tetrahedral [BO 4 ] and [GeO 4 ] units were the main network structure and the increasing of Tb 2 O 3 in glass promoted the conversion of BO 3 into BO 4 . The aforementioned structural change observed in MO glasses as a function of Tb 3+ ion concentration is reflected by the increase of glass density and decrease of molar volume. The obtained MO glasses exhibits a large of Verdet constant (at 632.8 nm) ranging from −49.98 to −120.54 Rad/T/m in a positive correlation with Tb 3+ ion concentration. The value of Urbach energy (ΔE) and optical band gap (E obg ) shows a negative correlation with Tb 3+ ion concentration. The luminescent intensity in 5 D 4 fluorescent level decreases with the increase of Tb 3+ ions concentration, and the concentration quenching is found when changing the content of Tb 2 O 3 from 15 mol% to 30 mol%.

Roughness of a surface as characterized by an atomic force microscope (AFM) is typically expressed using conventional statistical measurements including root-mean-square, peak-to-valley ratio, and average roughness. However, in these measurements only the vertical distribution of roughness (z-axis) is considered. Additionally, roughness of a surface as determined by AFM is a function of the scanning scale, sampling interval and/or scanning methods; therefore, the consideration and quantification of the lateral distribution (x and y) is necessary. Power spectral density (PSD) analysis provides both lateral and vertical signals captured from AFM images. By applying one of the commonly adopted models to the PSD data, the fractal model and k-correlation model, the equivalent root mean squared roughness, correlation length, fractal dimension and Hurst exponent are quantified. These parameters describe the spatial distribution of roughness and spatial length scale of the roughness values. Longer correlation len...

This paper is concerned with the inverse random source problem for a stochastic time fractional diffusion equation, where the source is assumed to be driven by a Gaussian random field. The direct problem is shown to be well-posed by examining the well-posedness and regularity of the solution for the equivalent stochastic two-point boundary value problem in the frequency domain. For the inverse problem, the Fourier modulus of the diffusion coefficient of the random source is proved to be uniquely determined by the variance of the Fourier transform of the boundary data. As a phase retrieval for the inverse problem, the phaselift method with random masks is applied to recover the diffusion coefficient from its Fourier modulus. Numerical experiments are reported to demonstrate the effectiveness of the proposed method.

Two coumarin derivatives based on spiro [fluorene-9,9′-xanthene] (SFX), named SFX-CS and SFX-CD, were successfully synthesized and their optical and electrochemical properties have been characterized. SFX-CS and SFX-CD were fabricated as dopant in TBADN-hosted OLED devices. The results show that SFX-CS exhibits better device efficiencies with maximum brightness of 6995 cd/m2, maximum luminous efficiency of 8.24 cd/A and maximum external quantum efficiency (EQE) of 3.86% at 10% doping concentration.

It is difficult for the traditional topic relevance algorithm based on word frequency and probability statistics model to deal with the ambiguous topic of search keywords, which leads to the retrieval results containing much information that users are not interested in. To solve this problem, a page-topic relevance algorithm based on BM25 and paragraph-semantic correlation is proposed in this paper. The semantic correlation of one page is calculated by the paragraph-semantic classification using a pre-trained deep neural network model, and is weighted with the BM25 retrieval score. Experimental results show that compared with the traditional BM25 algorithm, this algorithm can effectively improve the retrieval accuracy.

In this study, photocatalysis of phenol was studied using Cd-ZnO nanorods, which were synthesized by a hydrothermal method. The Cd-ZnO photocatalyst was characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy, and Fourier transform infrared (FT-IR) and UV-Vis spectroscopy. XRD patterns exhibit diffraction peaks indexed to the hexagonal wurtzite structures with the P63mc space group. SEM images showed that the average size of the Cd-ZnO nanorods was about 90 nm. Moreover, the nanorods were not agglomerated and were well-dispersed in the aqueous medium. FT-IR analysis confirmed that a surface modifier (n-butylamine) did not add any functional groups onto the Cd-ZnO nanorods. The dopant used in this study showed reduction of the bandgap energy between valence and conduction of the photocatalyst. In addition, effect of various operational parameters including type of photocatalyst, pH, initial concentration of phenol, amount of photocatalyst, and irradiation time on the photocatalytic degradation of phenol has been investigated. The highest phenol removal was achieved using 1% Cd-ZnO for 20 mg/l phenol at pH 7, 3 g/l photocatalyst, 120 min contact time, and 0.01 mole H2O2.

This paper reports on aspects of the production and trade of nineteenth century Chinese opium pipe bowls based on an examination of an assemblage from a Chinese goldfields settlement in New Zealand. Using energy dispersive X-ray fluorescence (EDXRF) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) we characterised the clay sources used for pipe production. Comparing those results with a stylistic analysis of the pipe bowls we developed a model for the production of opium pipe bowls and their distribution to nineteenth century Chinese diaspora communities. This is the first study to investigate Chinese opium pipe bowls using a combination of geochemical and stylistic analysis and is a novel application of archaeological science methodologies in Overseas Chinese Archaeology. The work reveals information about a group of potters and their production structures in Southern China and their trading connections in the Trans-Pacific region that had previously been historically and archaeologically opaque.

A significant obstacle in the development of phosphor-converted white-laser diodes (pc-wLDs) is associated with the laser-induced luminescence saturation of phosphors. YAG:Ce is a canonical yellow-emitting phosphor. However, there has been few systematic research of measurement and understanding of the luminescence saturation in YAG:Ce yet. Here, we analyze the luminescence saturation of a single-crystal YAG:Ce with a unique phosphor geometry. A novel characterization method, which enables the optical signals to be fully collected and analyzed, is introduced. The effects of both laser power and laser power density on the luminescence properties and colorimetric properties of the YAG:Ce are studied systematically. The results show that a single-crystal YAG:Ce has a high saturation threshold (over 360 W/mm2) so that only a very slight saturation behavior can be observed at a high power density. Furthermore, a pc-wLDs light source based on the combination of a single laser diode and a YAG:Ce phosphor exhibits remarkable efficiency and stability. Under the excitation of a 3.38 W blue laser (∼100 W/mm2), the white light emission with the luminous flux of 465 lm, the luminous efficacy (LE) of 145 lm/W, and the correlated color temperature (CCT) of 4980 K can be achieved.

The aim of the present study is to develop a Y 3 Al 5 O 12 :Ce (YAG:Ce) nanofiber-based phosphor layer for white-light-emitting diodes (WLEDs). The nanofiber was prepared by sol–gel and electrospinning methods with a diameter of 250–350 nm. Phase transitions from gel fiber to YAG fiber were well investigated by X-ray diffraction and thermal analysis. The results confirmed that a pure YAG phase formed at around 840 °C through direct crystallization of amorphous material. With strictly-controlled annealing process, the fiber morphology was well retained and the fiber-based phosphor layer could be obtained. The diameter of the fiber shrunk to 200–250 nm. WLED device was eventually obtained by directly coating a blue LED chip with the phosphor layer, without dispersion in resin. The packaged white LEDs exhibited a high luminous efficiency of 62 lm/W which was comparable with common commercial white LEDs (~80 lm/W). Furthermore, a tunable Correlated Color Temperature was achievable by controlling the thickness of the layer.

Waste amber glass is primarily disposed into landfills, and only small proportions are reused or remelted. Recycling waste amber glass reduces the quantity of disposal and minimizes the potential environmental impact on landfill sites. This study adopts the fast sintering method and the concept of recycled materials in fabricating high strength glass foams: ceramic green body composed of pulverized waste amber glass and pork bone is sintered at 850 °C for 600 s. Prepared glass foam samples were thermally, structurally, and mechanically characterized to investigate the processing–property relationships. Particularly, high flexural strength values between 16.71 ± 1.73 and 29.69 ± 3.23 MPa were reported for glass foams prepared in this study. High strength glass foams prepared in present work is promising as a component in a variety of advanced structural and energy material systems, given their unique properties including heat insulation, sound absorption, and shock-wave absorption.

Tripitaka, which means the “Great Treasury of Sutra”, is the most holy book of Tibetan Buddhism. There are limited numbers of Tripitaka persist today; most of them present various patterns of degradation. As little is known about the techniques used in Tripitaka, it appeared necessary to identify the substances and crafts applied and to further define adapted conservation treatment. We focused in this paper on two samples of Tibetan Tripitaka taken from the precious museum collections of Wuwei, dated from Ming Dynasty. Scanning electron microscope, X-ray diffraction, Raman spectrum, X-ray fluorescence and Fourier transform-infrared spectrum analyses were employed to characterize the composition of the writing pigment, paper filler and protective layer. The results reported here proved, for the first time, that Fe 2 O 3 and silver powder were applied in the writing pigment, red lead were used in the paper filler and the protective layer which employed to prevent silver powder from oxidation and sulfuration was identified as mixture of lipids which may contain beeswax. In the end, suggestions for protecting and restoring the ancient Tripitaka are provided.

In this research, grass-like CuO nanostructure was synthesized via a simple hydrothermal reaction at 100 °C for 6 h without using any surfactant. The as-prepared sample was further calcined at 500 °C for 1 h in nitrogen atmosphere for comparison. The surface morphology, crystal structure and chemical composition of the products were investigated by scanning electron microscopy (SEM), powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and room temperature photoluminescence spectroscopy (PL). The as-synthesized samples were also characterized systematically by electrochemical methods including cyclic voltammetry (CV), amperometric detection (i-t) and electrochemical impedance spectroscopy (EIS). It was found that the sample prepared after calcination in a nitrogen atmosphere exhibited better electrochemical catalytic performance for the determination of H 2 O 2 . In addition, high sensitivity (119.35 μA/mM) and fast amperometric response ( 2 O heterostructure, thus making it one of the promising candidates for the efficient and sensitive non-enzymatic amperometric detection of H 2 O 2 .

The measurement of surface roughness at micro-/nano-scale is of great importance to metrological, manufacturing, engineering, and scientific applications given the critical roles of roughness in physical and chemical phenomena. The surface roughness of materials can significantly change the way of how they interact with light, phonons, molecules, and so forth, thus surface roughness ultimately determines the functionality and property of materials. In this short review, the techniques of measuring micro-/nano-scale surface roughness are discussed with special focus on the limitations and capabilities of each technique. In addition, the calculations of surface roughness and their theoretical background are discussed to offer readers a better understanding of the importance of post-measurement analysis. Recent progress on fractal analysis of surface roughness is discussed to shed light on the future efforts in surface roughness measurement.

Novel Ni-doped titanate derived from protonated layered titanate has been fabricated via a simple ion-exchange process at room temperature. The as-synthesized product was calcined at 400 °C for 3 h to obtain the Ni–TiO 2 (anatase). The crystal structure of Ni–TiO 2 was studied by X-ray diffraction (XRD) and the surface chemistry was studied by X-ray photoelectron spectroscopy (XPS). It was found that doped nickel ions had inhibition effects on the crystallization of TiO 2 during calcination. The electrochemical properties of Ni–TiO 2 and undoped TiO 2 were both tested as anode materials for lithium-ion batteries at room temperature. While the undoped sample exhibited a mediocre performance, having a discharge capacity of 132 mAhg −1 after 50 cycles, the nickel-ion doped sample demonstrated noticeable improvement in both of its discharge capacity and rate capability; with a high capacity value of 226 mAhg −1 after 50 cycles. This improvement of lithium ion storage capability of Ni–TiO 2 can be ascribed to the Ni-doping effect on crystallinity and the modification of electrode/electrolyte interface of the TiO 2 structure.

Carbon nanotube films (CNT-1 and CNT-2) were fabricated in a vertical CVD gas flow reactor with water sealing. CNT-1 films consist of ordered crystalline carbon nanotubes, while CNT-2 are defective carbon nanotube films. The films are flexible and transferrable and can be used as binder-free anodes for lithium-ion batteries (LIB). Electrochemical measurements show that CNT-2 possess a reversible capacity of 452 mA h g −1 under a current density of 30 mA g −1 , which is higher than that of CNT-1 (375 mA h g −1 ) under the same current density. In addition, the CNT-2 shows a reversible capacity of 107.9 mA h g −1 after 500 cycles at a current density of 3000 mA g −1 , while 82.1 mA h g −1 for CNT-1 under the same condition. Good correlations between morphological factors, defective structure and electrochemical performance are observed.

Continuous free-standing Carbon Nanotubes (CNTs)/Titanium oxide (TiO2) composite films were fabricated in a vertical CVD gas flow reactor with water sealing by the One-Step Chemical Vapor Deposition (CVD) approach. The composite films consist of multiple layers of conductive carbon nanotube networks with titanium oxide nanoparticles decorating on carbon nanotube surface. The as-synthesized flexible and transferrable composite films show excellent electrochemical properties, when the content of tetrabutyl titanate is 19.0 wt.%, which can be promising as binder-free anodes for Lithium-Ion Battery (LIB) applications. It demonstrates remarkably high rate capacity of 150 mAh g−1, as well as excellent high rate cyclic stability over 500 cycles (current density of 3000 mA g−1). Such observations can be attributed to the relatively larger surface area and pore volume comparing with pristine CNT films. Great potentials of CNTs/TiO2 composite films for large-scale production and application in energy devices were shown.

Surface finishing techniques including polishing, etching and heat treatment can modify the topography and the surface chemical composition of glasses. It is widely acknowledged that atomic force microscopy (AFM) can be used to quantify the morphology of surfaces, providing various parameters including average, peak-to-valley, and apparent root-mean-square roughness. Furthermore advanced power spectral density (PSD) analysis of AFM-derived surface profiles offers quantification of the spatial homogeneity of roughness values along different wavelengths, resulting in parameters including equivalent RMS, Hurst exponent, and fractal dimension. Outermost surface (∼8 nm) chemical composition can be quantitatively measured by X-ray photoelectron spectroscopy. In this paper, we first developed a series of surface finishing methods for an aluminoborosilicate glass system by polishing, etching or heat treatment. The chemical composition and environment of prepared glass surfaces were quantified by XPS and topographical analysis was carried out by fractal and k-correlation model fitting of PSD profiles derived via AFM. The chemical environment of elements, as determined via XPS, present on the prepared surfaces are similar to those within the pristine bulk glass. The compositional evolution of polished and melt surfaces are discussed in context of corrosion phenomena associated with the grinding, polishing, and etching of surfaces and the thermal heat treatment utilized for processing, respectively. Good correlation between surface finishing methods, chemical composition and topographical parameters were observed. More importantly, extensive discussions on topographical parameters including equivalent RMS, Hurst exponent, and fractal dimension are presented as a function of processing method.

A seriesofBaTiO3 along withvarious flux oxideshasbeensinteredstep-wiselytoyieldalowsinteringtemperature flux glasscomposition. The developedglass flux (Ba-Cu-Bi-Bsystem)wasaddedtoBaTiO3 with differentamount,andeventuallyyieldedalowsinteringtemperatureof BaTiO3 at 900 1C with7wt% flux glassaddition.Toinvestigatetheinfluence ofprocessingmethods,a flux glassshell-BaTiO3 core structure was developedbyusingseparateballmillingscheduleofglassandbariumtitanatepowders.Comparisonofresultantdielectricpropertieswas made amongdifferentprocessingmethods,andthis flux shellprocessingmethodsnotablymodifies thedielectricpropertiesofsinteredsamples comparing toconventionalprocessingmethods.Thesubsequentstructuralinformation,morphology,andphasestabilityofsinteredsampleswere investigated byInfraredspectroscopy,X-rayphotoelectronspectroscopy(XPS),scanningelectronmicroscopy(SEM)andX-raydiffraction (XRD) respectively.93wt%BaTiO3-7 wt%glasswiththe flux shellstructuredisplayedaninhibitedcubicphasegraingrowth,andareduced tetragonality associatedwithCudopingwasconfirmed byX-raydiffraction.Ahighdielectricconstant(43000) aswellasalowlossyfactor (o0.03) ofthisparticularseriesofsamplewasreported.X-rayphotoelectronspectroscopyshowedthatbridgingoxygenspeciesdecreaseswith increasing Ndaddition,indicatingthattheNdbondstotheglassnetworkasanetworkmodifier insteadofbeingdopedintoBaTiO3 lattice through the flux shell.Thus,weconcludedthattheglass flux shellplaystheroleofsinteringadditive,Cudopingion(containedinglass)carrier, and Ndaliendopantblock.

Sborgite (Na[B5O6(OH)4]·3H2O) is a rare mineral, naturally occurring in only 2 known locations worldwide: California, USA and Larderello, Italy. Little is known of this mineral given its rarity in the natural world as well the inability, until now, to be produced in a single crystalline product. For the first time, we reported a single crystalline sborgite crystallization phenomenon caused by exposure of two different sodium borosilicate glasses to moisture. In this study, two homogeneous and two phase separated borosilicate glasses were prepared and exposed to moisture at room temperature (~25 °C) for up to 1 month. The powders were characterized by X-ray diffraction (XRD) and environmental scanning electron microscopy (ESEM). The results showed that exposure of all sodium borosilicate glasses to moisture can lead to crystallization of sborgite micro-crystals with a column-like morphology. In addition, it is shown that exposure of homogeneous glasses to humidity results in the formation of more highly crystalline sborgite than phase separated glasses of equal composition.

A series of germanium (Ge)-containing glasses were synthesized based on a starting glass composition of SiO2-ZnO-CaO-SrO-P2O5. Additions of GeO2 (6 and 12 mol%) were incorporated at the expense of SiO2, which retained the amorphous character, and each glass was processed to present similar particle size and surface area. Glass characterization using x-ray photoelectron spectroscopy (XPS) and magic angle spinning nuclear magnetic resonance (MAS-NMR) determined that the addition of GeO2 increased the fraction of lower Q-speciation and subsequently the concentration of non-bridging oxygens (NBO). Glass Polyalkenoate Cements (GPC) were formulated from each glass with 40, 50 and 60 wt% PAA, and presented time dependent solubility profiles (1, 10, 100, 1000 h) for the release of Si4+ (4–140 mg/l), Ca2+ (1–8 mg/l), Zn2+ (

The phase separation of high silicon composition 7.6Na2O·4K2O·8.4 CaO·70SiO2·8.9 CaF2·1.0 Al2O3 canasitebased glass ceramic during heat treatment was studied. The crystallization rate of calcium fluoride and canasite was estimated by using quantitative analysis of XRD. The non-isothermal DTA study shows that high silicon content increases the activation energy and restrains the crystallization of canasite appropriately. Through FE-SEM and SAXS, the early stage liquid–liquid phase separation was discovered in this kind of glass ceramic by long time heat treatment at 555 °C. Interestingly, the SAXS result shows that the small scale liquid–liquid phase separation has existed in the glass matrix intrinsically even after quenching.

3D porous nanostructures built from 2D δ-MnO2 nanosheets are an environmentally friendly and industrially scalable class of supercapacitor electrode material. While both the electrochemistry and defects of this material have been studied, the role of defects in improving the energy storage density of these materials has not been addressed. In this work, δ-MnO2 nanosheet assemblies with 150 m2 g−1 specific surface area are prepared by exfoliation of crystalline KxMnO2 and subsequent reassembly. Equilibration at different pH introduces intentional Mn vacancies into the nanosheets, increasing pseudocapacitance to over 300 F g−1, reducing charge transfer resistance as low as 3 Ω, and providing a 50% improvement in cycling stability. X-ray absorption spectroscopy and high-energy X-ray scattering demonstrate a correlation between the defect content and the improved electrochemical performance. The results show that Mn vacancies provide ion intercalation sites which concurrently improve specific capacitance, charge transfer resistance and cycling stability., Two-dimensional solids are of interest for energy storage due to their large accessible surface area, enabling rapid charge/discharge. Here, the authors quantify the point defects in oxide nanosheets, demonstrating that intentional introduction of charged point defects improves the charge storage behaviour.

The mixed alkali effect in x K 2 O-(30 − x ) Na 2 O-30P 2 O 5 -40ZnO was firstly observed. Density, DSC, DC electrical conductivity, chemical durability and IR have been carried out for x K 2 O-(30 − x ) Na 2 O-30P 2 O 5 -40ZnO glasses. The DC electrical conductivity was measured in the temperature range between 100 °C and T g . The strength of the MAE in T g , DC electrical conductivity, and activation energy has been determined. It is observed that the strength of MAE in DC electrical conductivity is less pronounced with the increase of temperature. The extremum of the glass transition temperature, the DC electrical conductivity, the activation energy, and the DR were observed along with the variation of K alkali ratio [K]/[K + Na] (alkali dosage is constant). The results showed that extremum was caused by the large energy mismatch for ions jumping between dissimilar alkalis' sites as Swenson's structural model suggested, generally shown as the K + vibration pathway blocking by the Na + due to the difference of ions' diameter. IR convinced the good correlation between MAE of x K 2 O-(30 − x ) Na 2 O-30P 2 O 5 -40ZnO system glasses and the origination of metaphosphate structure, secondarily pyrophosphate, and [ZnO 6 ] octahedral.

Pottery, bone implements, and stone tools are routinely found at Neolithic sites. However, the integrity of textiles or silk is susceptible to degradation, and it is therefore very difficult for such materials to be preserved for 8,000 years. Although previous studies have provided important evidence of the emergence of weaving skills and tools, such as figuline spinning wheels and osseous lamellas with traces of filament winding, there is a lack of direct evidence proving the existence of silk. In this paper, we explored evidence of prehistoric silk fibroin through the analysis of soil samples collected from three tombs at the Neolithic site of Jiahu. Mass spectrometry was employed and integrated with proteomics to characterize the key peptides of silk fibroin. The direct biomolecular evidence reported here showed the existence of prehistoric silk fibroin, which was found in 8,500-year-old tombs. Rough weaving tools and bone needles were also excavated, indicating the possibility that the Jiahu residents may possess the basic weaving and sewing skills in making textile. This finding may advance the study of the history of silk, and the civilization of the Neolithic Age.

CuAlO2 has been examined as a potential luminescent material by substituting Eu for Al cations in the delafossite structure. CuAlO2:Eu3+ nanofibers have been prepared via electrospinning for the ease of mitigating synthesis requirements and for future optoelectronics and emerging applications. Single-phase CuAlO2 fibers could be obtained at a temperature of 1100 °C in air. The Eu was successfully doped in the delafossite structure and two strong emission bands at ~405 and 610 nm were observed in the photoluminescence spectra. These bands are due to the intrinsic near-band-edge transition of CuAlO2 and the f-f transition of the Eu3+ activator, respectively. Further electrical characterization indicated that these fibers exhibit semiconducting behavior and the introduction of Eu could act as band-edge modifiers, thus changing the thermal activation energies. In light of this study, CuAlO2:Eu3+ fibers with both strong photoluminescence and p-type conductivity could be produced by tailoring the rare earth doping concentrations.

Silver (Ag) coatings have been incorporated into many medical materials due to its ability to eradicate harmful microbes. In this study, glass microspheres (SiO2–Na2O–CaO–Al2O3) were synthesized and employed as substrates to investigate the effect Ag coating has on glass solubility and the subsequent biological effects. Initially, glasses were amorphous with a glass transition point (Tg) of 605℃ and microspheres were spherical with a mean particle diameter of 120 µm (±27). The Ag coating was determined to be crystalline in nature and its presence was confirmed using scanning electron microscopy and X-ray photoelectron spectroscopy. Ion release determined that Ag-coated ( Ag-S) microspheres increased the Na+ release rate but slightly reduced the Ca2+ and Si4+ release compared to an uncoated control ( UC-S). Additionally, the Ag-S reduced the pH to just above neutral (7.3–8.5) compared to the UC-S (7.7–9.1). Antibacterial testing determined significant reductions in planktonic Escherichia coli ( p = 0.000), Staphylococcus epidermidis ( p = 0.000) and Staphylococcus aureus ( p = 0.000) growth as a function of the presence of Ag and with respect to maturation (1, 7, and 30 days). Testing for toxicity levels using L929 Fibroblasts determined higher cell viability for the Ag-S at lower concentrations (5 µg/ml); in addition, no significant reduction in cell viability was observed with higher concentrations (15, 30 µg/ml).

Superoxide Dismutase (SOD) was proposed as a potential scavenger of carbon radicals in ancient carbonized silk fabrics. Ancient and artificially carbonized silk samples were treated using this method. The optimal experimental conditions of the treatment were determined by variance analysis. The effects of the scavenging on carbonized silks were investigated by electron paramagnetic resonance (EPR). The results showed that the carbon radicals in both ancient and artificially carbonized silks were cleared to a great extent. The ageing resistance of the treated samples and scanning electron microscope (SEM) images of samples before and after treatment ensured that the treatment would not aggravate the deterioration of silk. Thus, the potential of SOD to scavenge carbon radicals in historic silk was demonstrated. Our research may help to alleviate further degradation which could occur during preservation of silk.

The mechanically improved foam glass composite toughened by glass fiber was prepared by sintering technique, using waste sodium-calcium silicon flat glass powder as main raw materials. In this study, the preparation and properties of the samples were characterized by differential thermal analysis (DTA), field-emission scanning electron microscopy (FESEM) and mechanical property test. The specific strength of the composite was defined for the first time, and applied into the investigation of mechanical property. The results show that the specific improved bending strength of 10.45–22.26 MPa/(g cm − 3 ), and the specific compressive strength of 30.45–34.34 MPa/(g cm − 3 ) can be displayed when sintered at 790–815 °C with the addition of 5–25 wt.% glass fiber. Good correlations between the microstructure (in particular the fiber distribution), the high specific strength and the high modulus of elasticity of glass fibers.

The high strength porous foam glass can be widely used as heat insulation, sound absorption, shock wave absorbing constructional materials. The new high strength foam glass–ceramics from waste cathode ray tube were prepared by sintering method, and used SiC as foam agent. In this study, the samples were characterized by differential thermal analysis (DTA), X-ray diffraction (XRD), scanning electron microscopy (SEM) and mechanical property. The effect of micro-crystals reinforcement on the bending and compressive strength was investigated by the strength tests. The crystallization behavior of the samples was determined by the applying of XRD and SEM. The experimental results showed that the amazingly high mechanical strength values of 5.61–23.73 MPa can be obtained by changing the dosage of SiC and using the sintering temperature around 840–850 °C, leading to the precipitation of Pb, Pb 3 O 4 , and Al 6 Si 2 O 13 .Good correlations between mechanical strength, precipitation of micro-crystals and SiC dosage were observed.