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Nanofibers of TiO 2 , CeO 2 , Y 2 O 3 -stabilized ZrO 2 and SrTiO 3 with length of a few micrometers and average diameters of 50–250 nm were fabricated by electrospinning, the structures and morphologies were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscope, the stoichiometry by Raman spectrum and X-ray photoelectron spectroscopy. And the optimum electrospinning conditions and calcination temperatures were determined. [ABSTRACT FROM AUTHOR]

The application of magnesium alloys is rather limited due to their poor corrosion resistance despite of their promising mechanical properties. Alloying is considered one of the most efficient methods to influence the corrosion susceptibility of Mg alloys either by altering the bulk microstructures or by changing the surface chemistries. In the present study, the effects of Sr addition on the microstructure and corrosion properties of a Mg-Zn-Ca alloy were studied. The microstructure characteristics of the alloys were investigated using optical microscopy, scanning electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy, while the corrosion properties were evaluated by hydrogen collection method and electrochemical techniques including potentiodynamic polarization and electrochemical impedance spectroscopy. The results indicate that Sr addition significantly deteriorates the corrosion performance of the Mg-Zn-Ca alloy mainly by forming more micro-galvanic couples due to the precipitation of the more populous secondary phase particles. The corrosion product film accumulated on the sample surface marginally affects the corrosion resistance, as their compactness is rather compromised as the immersion time is prolonged. • The volume fraction of the secondary phases increased by adding Sr into the Mg-Zn-Ca alloy; • Sr addition leads to the formation of Mg 17 Sr 2 phase in Mg-1Zn-0.3Ca (wt.%) alloy; • The addition of Sr into the Mg-1Zn-0.3Ca (wt.%) leads to a higher corrosion rate. • Corrosion rates of the Mg-Zn-Ca-(Sr) alloy mainly affected by secondary phases through the microgalvanic mechanism. [ABSTRACT FROM AUTHOR]

• CASA was synthesized via esterification of CA and SA. • The raw materials were environmental-friendly and low-cost. • All CASA showed excellent antibacterial activity for E. coli and S. aureus. • The antibacterial groups can be linked to CA more firmly by chemical bonds. In this paper, cellulose acetate (CA) with different degree of substitution (DS) of 2.17∼1.75 were obtained through hydrolysis of cellulose diacetate (CDA). Furthermore, novel cellulose acetate sorbate (CASA) were synthesized by esterification of CA and sorbic acid (SA). The DS of sorbyl groups varied within 0.12–1.20 by adjusting composition ratio, reaction time and temperature. Fourier transform infrared spectroscopy (FTIR), Nuclear magnetic resonance spectroscopy (NMR) and elemental analysis were used to determine the chemical structure. Scanning electron microscopy (SEM) indicated CASA showed denser surface morphology than CA. Thermal properties and crystallization of CASA were slightly decrease but did not affect their service performance. Specifically, all CASA showed excellent antibacterial ability, the maximum relative bactericidal rate reached 81.5 % for Escherichia coli (E. coli) and 95.4 % for Staphylococcus aureus (S. aureus), respectively. Moreover, the obtained CASA films using casting technique possessed good mechanical properties. These antibacterial CASA exhibited potential application in healthcare fields. [ABSTRACT FROM AUTHOR]

The ciliate Miamiensis avidus causes scuticociliatosis in Japanese flounder Paralichthys olivaceus . We previously reported three serotypes of this ciliate distinguishable by serotype-specific antigenic polypeptides (serotype I, 30 kDa; serotype II, 38 kDa; serotype III, 34 kDa). In this study, we determined the localization site of the serotype-specific polypeptides in the ciliate and determined the genes encoding the polypeptides, using the isolates IyoI (serotype I), Nakajima (serotype II), and Mie0301 (serotype III). SDS-PAGE and immunoblot analysis of cilia, membrane proteins, and cytoskeletal elements of the ciliates revealed that the polypeptides were abundant in the former two. Scanning electron microscopy of ciliates immobilized by homologous antiserum showed morphological changes in the cilia. These evidences suggested that the polypeptides were ciliary membrane immobilization antigens. The ciliary genes identified showed low identity scores—< 51.5% between serotypes. To differentiate the serotypes, we designed serotype-specific PCR primer sets based on the DNA sequences. The PCR-based serotyping results were completely consistent with conventional serotyping methods (immobilization assay and immunoblot analysis). Twenty of 21 isolates were classified as either serotype I or II, and one isolate was undistinguishable. The combination of species-specific PCR previously reported and three serotype-specific PCR could be useful for identifying, serotyping, and surveillance for occurrences of new serotypes of M. avidus . [ABSTRACT FROM AUTHOR]

In this work, ferric ceria nanofibers (FC NFs) with different iron contents were successfully fabricated through electrospinning followed by calcination at 550 °C. The resultant FC NFs were blended with multi-walled carbon nanotubes (MWCNT@FC) and utilized to modify the glassy carbon electrode (GCE) for uric acid (UA) detection. The XRD patterns revealed that FCs NFs have cubic lattice structure. The Raman and X-ray photoelectron spectroscopy (XPS) were confirmed the presence of oxygen vacancies with Fe(II)/Fe(III) and Ce(III)/Ce(IV) chemical states of the surface ions. The surface morphology was investigated through scanning electron microscopy (SEM) and particle size analysis was performed using transmissions electron microscopy (TEM). The electrochemical properties of MWCNT@FC NFs were evaluated through cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods under varied conditions. The results demonstrated the crucial effects of Ce/Fe molar ratio on the electrocatalytic performance due to the sufficient oxygen vacancies originating from the incorporation of Fe3+ ions into ceria (CeO 2). Furthermore, blending with 70 wt% MWCNT (MWCNT70@FC) gave rise to a significant improvement on the electrical conductivity. The MWCNT70@FC-2 modified GCE composite with Ce/Fe molar ratio of 1:1 displayed high performance towards UA detection at 6.0 pH.The detection limit of 0.3 μM was achived with wide linear range from 0.5 μM to 500 μM. The MWCNT70@FC-2 demonstartedadequate stability and reproducibility for urice acid detection. The high selectivity and accuracy was further established for prepared MWCNT@FC-2 composite sensor by detecting UA in real biological samples. The obtained results were precise and reproducible. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Bicomponent cellulose/PAN fiber was successfully fabricated by electrospinning method. • The bicomponent fiber mat showed high oil-in-water separation efficiency. • The as-fabricated fiber showed excellent oil/water separation for corrosive solutions. • The fiber mat exhibited good extent of reusability for oil-in-water separations. Abstract In this study, a simple electrospinning method was employed for the fabrication of a durable and renewable cellulose/polyacrylonitrile (cellulose/PAN) composite nanofiber by alternatively piled one over other as stacking. The stacking layers of cellulose/PAN composite fiber was subjected to the hot roller press at 80 °C to enhance the firm attachment of fibers. The hydrophilic composite fiber was fabricated for oil-in-water mixture separation in harsh conditions of different pH. The fibers were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and thermal stability was monitored by TGA analysis. The tensile stress and the surface wetting behavior were greatly improved for cellulose/PAN composite fiber. The different oils like n-hexane, diesel oil, and toluene were used to prepare oil-in-water mixture solutions. The hydrophilic composite fiber served as a substrate to ensure the high water permeation flux and high separation efficiency with excellent stability and durability. This work projects an easy cost-effective fabrication method of composite fiber for on-demand oil-in-water separation process having good application in adverse situations with excellent recyclability and the maximum separation efficiency up to 97.31%. [ABSTRACT FROM AUTHOR]

Abstract Herein, performance degradation of pouch type of 20 A h lithium ion battery from electric bus is clarified after a classification using the resistance value from A to D grade. The obtained cells are carefully disassembled to produce cathode, anode, and separator. Scanning electron microscopy and energy dispersive spectroscopy analysis reveal that morphological change of electrode mostly occur in the anodes surface in D-grade cells, while cathodes of all the grades mostly remain similar. Although the change of crystalline structure of all electrodes is negligible, a growth of solid-electrolyte interphase film mostly happen in the D-grade anodes, which is confirmed by X-ray photoelectron spectroscopy analysis. Furthermore, the degradation of cycle and rate performance happen in the anode of D-grade cells, whereas the cathodes remain invariant irrespective of grade. Furthermore, the disassembled separators exhibit that the Gurley number of separators is commonly increased in the used cells. Highlights • The used 20 Ah lithium ion pouch cells from electric bus were classified using resistance. • The LIB cells separated in 4 grade level were dissembled to obtain cathode, anode and separator. • Surface film increase occurred in anode in D graded LIB cells. • Resistance increase and capacity decrease were mostly attributed to anode degradation. • Cathode and separator remained less-changed by real operation. [ABSTRACT FROM AUTHOR]

A combined buffer layer growth process was developed to grow crack-free GaN layers on 8-inch Si(111) wafers and so light-emitting diodes (LEDs). The combined buffer layer consisted of 2 nm-thick low-temperature (LT, 850 °C)-AlN, 8 nm-thick graded-temperature AlN, and 200 nm-thick high-temperature (HT, 1100 °C)-AlN layers. The X-ray diffraction (XRD) results showed that the LT-HT-AlN buffer layer exhibited better crystal quality than the HT-AlN buffer layer. The atomic force microscopy (AFM) images revealed that compared to the LT-HT-AlN buffer layer, the HT-AlN buffer layer had a rough surface with numerous bright spots, which correspond to N-polar AlN hillocks. Scanning electron microscopy (SEM) results showed many pits in the HT-AlN buffer layer. Transmission electron microscopy (TEM) results showed that the HT-AlN buffer layer contained about 1.3 nm-thick amorphous Si x N y layer at the interface, while the LT-HT-AlN buffer layer showed a relatively smooth interface. It was further shown that using the LT-HT-AlN buffer layer, high-quality crack-free n -GaN layers (2.5 μm-thick) were grown on the 8-inch Si(111) substrate, which was confirmed by the XRD and cathodoluminescence results. Subsequently, packaged vertical LEDs (chip size: 1400 × 1400 μm 2 ) grown on the LT-HT-AlN buffer layers showed higher light output power and chip yield than LEDs with the HT-AlN buffer layer. [ABSTRACT FROM AUTHOR]

[Display omitted] • Li+, Na+, K+ and Rb+ enhanced emissions of Yb3+/ Ho3+ doped Y 2 O 3 films notably. • Li+ involves three factors that enhance luminescence, the other through two. • Li+ adjusted color coordinate towards the 539 nm direction, K+ towards to 550 nm. • Na+ and Rb+ can provide a color-stable emission enhancement. In this paper, alkali ion (Li+ Na+ K+ and Rb+)-doped Y 2 O 3 :Yb3+/Ho3+ up conversion films were prepared using the sol–gel method. The structures of the films were studied by using X-ray diffraction, scanning electron microscopy, and Raman spectroscopy. A series of high-quality thin films with good crystallization were prepared. For all samples, two emission bands were observed: green emission at 539 (5 5 0) nm and red emission at 664 nm, which can be attributed to 5F 4 (5S 2)→5I 7 and 5F 5 →5I 8 , respectively. The green emission is dominant, and the red emission is extremely weak. The effect of each alkali-ion dopant on the emission and color adjustment of samples was investigated. The green emission intensity is increased by a factor of 6.33 (Li), 2.03 (Na), 4.82 (K) and 1.92 (Rb) with increasing alkali-ion doping concentration, and red emission is increased by a factor of 7.80 (Li), 1.92 (Na), 4.78 (K) and 1.90 (Rb). The extreme value appears earlier with increasing ion radius. Li+ doping boosts luminescence in three ways, and the other alkali ions affect the light emission in two ways. Li+ doping and K+ doping can be used to adjust the color coordinates towards the 539 nm and 550 nm directions, respectively. Na+ and Rb+ doping can enhance emission with a stable color. This means that each alkali ion is a suitable choice as a color-regulating ion and can play a role in the regulation of luminescence. [ABSTRACT FROM AUTHOR]

In this study, a series of well-crystallized Yb3+/Er3+/Tm3+-tridoped Y 2 O 3 –ZnO ceramic phosphors were prepared using sol–gel synthesis, and the phosphor structures were studied using X-ray diffraction, scanning electron microscopy, and thermogravimetric analysis. The phosphors had excellent physical stability and porous structure. All phosphors generated blue, green, and red emission bands attributed to Tm: 1G 4 →3H 6 , Er: 2H 11/2 (4S 3/2)→4I 15/2 , and Er: 4F 9/2 → 4I 15/2 radiative transitions, respectively. The emissions were intensified twice by tuning the Tm3+ ratio in the host matrix Y 2 O 3 and ZnO parts. The color coordinates were adjusted by tuning both the Tm3+ concentration and the excitation laser pump power to shift the color coordinates and only enhance the brightness, respectively. Meanwhile, heating phosphors can also linearly adjust the color coordinates of the luminescence. Therefore, it can also be used as a fluorescence thermometer in the field of temperature sensor. The study findings will broaden the phosphor practical application potential. • The phosphors had excellent physical stability and porous structure. • The emission color was turned by adjusting the Tm3+ concentration. • Increasing excited power adjusted emission from white to blue at low Tm3+ concentrations. • Increasing excited power only increased brightness at high Tm3+ concentrations. [ABSTRACT FROM AUTHOR]