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The high porosity and poor mechanical properties limit the application of calcium hexaaluminate (CA6) ceramics in the field of colored ceramics. In order to synthesize a new blue ceramic material, Ni2+ and Ti4+ were introduced into CA6 as an effective system to replace cobalt-aluminum spinel. Blue ceramic material with low porosity and good mechanical properties was successfully prepared by doping nickel oxide and titanium oxide into CA6 using a high-temperature solid-phase method. The results show that the sintering, densification, mechanical and optical properties of the ceramic material are affected by the amount of NiO and TiO2 doping. The color for the sample is related to the energy change produced by the substitution of Ni2+ and Ti4+ for Al3+, producing yellow light absorption and blue light reflection in the visible range. Due to its good mechanical and color properties, it can be used as a new type of environmentally friendly ceramic with great industrial potential for a wide range of high-tech applications such as mobile phone backplanes.

Advanced oxidation technology is considered to be the most potential wastewater treatment technology. As one of the advanced oxidation technologies, the three-dimensional electrochemical system (3DES) is often used to treat industrial wastewater that is difficult to degrade. Sulphonated phenolic resin (SMP) was treated as a characteristic pollutant in sulfonated drilling wastewater. The separate effect of current, the dosage of particle electrodes, chloride ion concentration and initial pH on chlorinated by-products were analyzed by response surface methodology (RSM). Results showed that current is the most dominant factor, followed by the dosage of particle electrodes. The ultraviolet-electrolysis (UVEL) system was implemented by adding ultraviolet light under the optimal electrolysis (EL) system. The chemical oxygen demand (CODcr) and total organic carbon (TOC) removal rates of the UVEL system were respectively increased by 19% and 29.39% compared with the EL system, the concentration of chlorinated by-products was also reduced by 534.4 mg/L when the UV irradiance was 5.24 mW/cm2. These results indicated that the UVEL system degrades SMP more thoroughly. The enhanced reaction mechanism of the UVEL system and the possible degradation pathway for SMP were proposed by controlling free radical quenching experiments and the product of EL and UVEL processes. The results showed that the high degradation efficiency of the UVEL system could be attributed to the synergistic degradation mechanism present in the UVEL system, where the photolysis of active chlorine species (ACl) promotes the increase of hydroxyl radical (·OH). HIGHLIGHTS Current is the most important factor affecting ACl change.; ACl is the main active substance to degrade SMP in EL system.; The synergism degradation mechanism existing in the UVEL can be attributed to the additional increase of ·OH.; Less chlorinated by-products were produced in the UVEL degradation system.

The application of direct methanol fuel cells is hampered by not only low activity but also poor stability and CO tolerance of Pt catalyst. The electrocatalytic activity and stability of platinum nanoparticles assembled on different kinds of flower-like CeO2 (fCeO2)/[Graphene (G), Carbon Vulcan (XC-72) and Ordered Mesoporous Carbon (CMK-3)] composite supports for methanol electro-oxidation were investigated. The catalyst samples were characterized by X-ray diffraction, scanning electron microscopy (SEM), transmission electron microscopy, and X-ray photoelectron spectroscopic. The electrochemical properties of the catalysts were measured by a three electrode system on electrochemical workstation (IVIUM). The results show that the Pt grain size of Pt-fCeO2/G catalyst is the smallest. Compared with Pt-fCeO2/XC-72 and Pt-fCeO2/CMK-3, Pt-fCeO2/G has the lowest binding energies of Pt(0) and more hydroxyl, carbonyl, carboxyl and other oxygen-containing functional groups. This kind of oxygen-containing functional group can facilitate methanol oxidation and relieve CO poisoning. The mass-specific activity of Pt-fCeO2/G is 2.2 and 3.6 times higher than that of Pt-fCeO2/CMK-3 and Pt-fCeO2/XC-72, respectively. The activation energy of Pt-fCeO2/G catalyst for electrocatalytic oxidation methanol is the lowest, which is 16.63 kJ mol−1. Pt-fCeO2/G appears to be a promising and cost effective methanol oxidation anode catalyst.

Nano CeO2–ZrO2 composites with different shapes are synthesized by using hydrothermal and deposition-precipitation methods, and used to obtain Pt/CeO2–ZrO2/RGO catalysts, where reduced graphene oxide(RGO) acts as a carrier. X-ray Diffrattometry (XRD), Raman spectroscopy, transmission electron microscopy, X-ray photoelectron spectroscopy (XPS) detection methods are used to characterize morphology, phase composition, exposed planes and oxygen defects of the catalyst. The obtained CeO2–ZrO2 supports are in the form of nanorods, nanospheres, and nanocubes, which mainly expose (110), (111), and (100) planes, respectively. Electrocatalytic methanol oxidation tests onto the Pt/CeO2–ZrO2/RGO catalysts show that the electrochemically active surface area and the peak current density of nanorods are the largest ones among the three catalysts, reaching 61.4 m2/g and 230 A/g. In addition, the long-term discharge stability and CO poisoning resistance of the nanorod-shaped Pt/CeO2–ZrO2/RGO catalyst are the highest ones among the examined catalysts.

The specific energy absorption of a thin-walled tube can be improved by filler. This study examined the potential use of a cheaper biomass filler, paper scraps, to enhance the energy absorption characteristics of the structure while reducing its cost, compared to that with a traditional filler such as foam material. Quasi-static crushing tests and finite element simulations were performed by using the explicit non-linear finite element software LS-DYNA to determine the improvements to the mean crushing force and specific energy absorption of the steel tube when filled with different densities of paper scraps. The mean crushing force and specific energy absorption of the empty tube, the paper scraps, and thin-walled tube filled with paper scraps were determined, and corresponding numerical simulations were performed. The simulation and test results showed that the impact performance of tube filled with paper scraps was greatly improved when paper scraps density was 0.35 g/cm3. By optimizing paper scraps filling structure, a new structure that could further enhance the specific energy absorption was obtained. The optimal scheme could increase the specific energy absorption of Q345 steel tube by 11.35%.

In this paper, the PtNi alloy was embedded into the surface layer of three-dimensional carbon nanosheets (CNSs) with a special layered structure. We controllably adjusted the ratio of Pt/Ni to form large particle alloy with Pt coating Ni and a small number of hollow PtNi alloy pellets. The electro-catalytic methanol oxidation activity and durability of the catalysts were estimated by cyclic voltammetry and chronoamperometric techniques. The results indicated that the doping of Ni effectively improved the activity and anti-poisoning of the catalyst in the methanol electrocatalytic oxidation reaction (MOR). Transmission electron microscopy (TEM), Raman spectroscopy, nitrogen adsorption-desorption techniques, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) were used to explore the composition, morphology and structure of these catalysts. It is discovered that the Pt–Ni/CNSs (2:1) sample exhibits the best MOR activity with a peak current density of 15.03 mA cm−2 at the forward scan due to the excellent lamellar structure, good crystallinity and abundant pore structure of CNSs, which is benefit to form ultrahigh specific surface area, superb electron and ionic conductivity.

The doping of nickel and titanium is evaluated with the goal of coloring calcium hexaluminate ceramic (CaAl12−2xNixTixO19) and improving mechanical properties. The samples prepared by solid-phase reaction are studied with X-ray diffraction, UV–Vis diffuse reflection, a Konica Minolta colorimeter, scanning electron microscopy, and an indentation test of hardness. The increase in dopant content increases the fracture toughness of CaAl12O19, enabling us to obtain a pure blue ceramic material with a doping amount of x = 0.8. With the increase of Ni2+ and Ti4+, the color of the sample changes. Among the samples, the most vivid blue hue is obtained for an x value of 0.8 with a reflection peak at 473 nm in the UV spectrum and a blueness value (− b*) of 49.2 in the CIE L*a*b* system, which is bluer than cobalt-doped ceramics. The emission spectra of CaAl12O19 in the visible region confirmed that Ni2+ replaces Al3+ in the tetrahedron and causes an electron transition. The results also indicate that the incorporation of Ni2+ and Ti4+ increases the hardness of the sample and the fracture toughness, with the hardness of pure calcium aluminate increased by 22.1%.

Black zirconia ceramics has many problems, such as uneven color and poor phase stability. The reason for this phenomenon is that the colorant uses a colorant with a complex black spinel structure, and also the application of a dyeing method. To improve the color uniformity and phase stability of black ceramics, TiO2 was introduced to replace the traditional complex black spinel, a high-temperature reduction method (HTR) was employed to prepare a black Ti-doped zirconia ceramic, stead of the conventional dyeing method. After the HTR at 1400 °C, the concentration of Ti3+ and oxygen vacancies increased, and the lightness of the ceramic samples decreased from 93.48 to 44.17. The black ceramic is uniform in color and stable in phase, avoiding the disordered phase of the spinel doped multiphase zirconia ceramic. The results indicate that the overall color of the samples depends on the development mechanism of the color center. The formation of color centers (F+ centers) in this work was related to the electronic transition of Ti 3d states and oxygen vacancies generated during the HTR. F+ centers cause a strong light absorbance over the entire visible light range (400–750 nm), so that the color of the ceramics is black. Based on their good color attributes, black ceramics have great potential in industry, for example as the back plate of mobile phones.

Red zirconia ceramics is unstable at high temperature and the saturate degree of color is very poor. To broaden the application especially in colorful backsheet of mobile phone, a red zirconia ceramics based on Ce-doped yttria stabilized zirconia (YSZ) was sintered at 1450 °C. Then, the red zirconia ceramics were prepared by a high-temperature reduction method. As the reduction temperature and the doping of CeO2 increased, the value of a* (a 0 indicates red) first increased and then decreased. The redness of the ceramic sample reached the highest value of 32.5. The maximum fracture toughness reached was 9.6 MPa m1/2. According to first principle calculations, it is shown that the Ce 4f state appears near the Fermi level after Ce2O3 doping. During the electronic transition from 4f states of Ce atoms to 4d states of Zr and Y atoms, it combines with the oxygen vacancies generated during the reduction to form a color center. The appearance of the color centers causes a band gap of about 2.0 eV in the crystal. The corresponding absorption wavelength is 480–500 nm, and thus the observed color is red. This work provides a way to prepare stable high-temperature red zirconia ceramic with high saturate degree of color. The color centers development mechanism was considered to be the formation of red.

The inherent sophisticated structure of wood inspires researchers to use it as a natural template for synthesizing functional nanoparticles. In this study, pure copper nanoparticles were synthesized using poplar wood as a natural inexpensive and renewable template. The crystal structure and morphologies of the copper nanoparticles were characterized by X-ray diffraction and field emission scanning electron microscopy. The optical properties, antibacterial properties, and stability of the hybrid wood materials were also tested. Due to the hierarchical and anisotropic structure and electron-rich components of wood, pure copper nanoparticles with high stability were synthesized with fcc structure and uniform sizes and then assembled into corncob-like copper deposits along the wood cell lumina. The products of nanoparticles depended strongly on the initial OH- concentration. With an increase in OH- concentration, Cu2O gradually decreased and Cu remained. Due to the restrictions inherent in wood structure, the derived Cu nanoparticles showed similar grain size in spite of increased Cu2+ concentration. This combination of Cu nanostructures and wood exhibited remarkable optical and antibacterial properties.

Nanosized Fe3+ and Eu3+ codoped CeO2 solid solutions were synthesized via hydrothermal method. The crystalline structure of Ce1−x(Fe0.5Eu0.5)xO2−δ (x=0.00–0.30) solid solutions was carried out by the X–ray diffraction technique, and the spectrum features were identified by UV–Vis and Raman spectroscopy, respectively. It was observed that the cell parameters were first increased then decreased by increasing the doped ions content. The phase separation was detected when the dopant concentration reached to x=0.30. UV–Vis spectrum showed that the width of the band gap gradually reduced by increasing the doped content, and the solid solubility was determined to be x=0.20. The Raman technique displayed that the peak position of F2g mode gradually shifted to lower frequencies from 465 cm−1 for x=0.00 to 440 cm−1 for x=0.20. The catalytic effects of Ce1−x(Fe0.5Eu0.5)xO2−δ solid solutions on the electrochemistry properties of Mg2Ni/Ni were measured by mixing them together via ball milling technique. The electrochemical properties of the Mg2Ni/Ni–Ce1–x(Fe0.5Eu0.5)xO2−δ composites showed that the maximum discharge capability Cmax and the cycle stability were improved obviously. Meanwhile, the EIS characteristic also indicated that the doped solid solutions could enhance the rate of charge transfer on the surface of alloy. The catalytic effect of the solid solutions was speculated to rely on both the concentration of oxygen vacancies and the cell volumes of the solid solutions.

Spherical CeO2 and CeO2-ZrO2 solid solutions are prepared using a hydrothermal method, Pt/CeO2-ZrO2/GO and Pt-CeO2/GO catalysts are prepared using graphene as a carrier, and the effects of the addition of a CeO2-ZrO2 solid solution on the electrocatalytic activity, stability and anti-CO poisoning performance of methanol fuel cell anodes are investigated. The catalyst samples are characterized via X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM), and the electrochemical properties of the catalysts are investigated using an electrochemical workstation (IVIUM). The results show that Pt/CeO2-ZrO2/GO has a higher electrocatalytic activity and stability against CO oxidation than Pt-CeO2/GO, Pt/GO and commercial Pt/C catalysts, which is attributed to ZrO2. When Zr4+ is added into the CeO2 lattice, the activity of oxygen in the CeO2 lattice, the oxygen mobility and the oxygen vacancies are increased, the oxygen storage capacity is improved, and the intermediate product of CO is more easily oxidized. This finding indicates that Pt/CeO2-ZrO2/GO is a methanol oxidation anode catalyst with a good catalytic activity, stability and resistance to CO poisoning.

The electrocatalytic activity and stability of Pt/C catalyst modified by using CeO2-ZrO2 mixed oxides for the alcohols electrochemical oxidation as probes were investigated. The catalyst samples were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The electrochemical properties were measured by a three electrode system on electrochemical workstation (IVIUM). The results showed that the presence of CeO2-ZrO2 might be associated with the presence of Pt, which indicated that possibly there was synergistic effect between CeO2-ZrO2 and Pt nanoparticles. The electrocatalytic activity and stability of Pt-MOx/C (M=Ce, Zr) for methanol and ethanol oxidation was better than that of Pt-CeO2/C, which was attributed to that CeO2-ZrO2 composited oxides enhanced oxygen mobility and promoted oxygen storage capacity (OSC). Furthermore, the best performance was found when the molar ratio of CeO2 to ZrO2 was 2:1 for the oxidation of methanol and ethanol. The forward peak current density of Pt-MOx/C (M=Ce, Zr, Ce:Zr=2:1) towards the methanol electrooxidation was about 3.8 times that of Pt-CeO2/C. Pt-MOx/C (M=Ce, Zr) appeared to be a promising and less expensive methanol oxidation anode catalyst.

In order to investigate the leaking characteristics of the port plate pair in primary three-row axial piston pump/motor, the present paper deducts two equations about the leakage of oil film, analyzes the effect of such parameters as oil film thickness, sealing tape width, and central angle of waist-like slot on the leakage, and arrives at the following conclusions: for the primary three-row axial piston pump/motor, the angle of heel on cylinder increases the leakage of port plat pair, but high-pressure areas on its both sides with similar displacement weaken the effect of the scope and direction of angle of heel on the leakage and help to stabilize the port plat pair’s leakage and maintain the fluid lubrication; widening the sealing tape in a reasonable range can effectively bring down the leakage and raise the volume efficiency; in case of any change in the central angle of waist-like slot, the leakage of primary three-row axial piston pump/motor appears to be more stable than common type, which is more favorable for maintaining the fluid lubrication in the port plat pair. This study can shed some light on the structural design of the primary three-row axial piston pump/motor.

Lithium-ion battery cathode material Li1+xV3O8 is synthesized by a citric acid/tartaric acid assisted sol–gel method and sintered at 350 °C, 450 °C and 550 °C for 3 h for the formation of Li1+xV3O8 phase. The synthesized samples were fully characterized by FTIR, TG/DTA, XRD, SEM, EIS and charge–discharge tests. Li1+xV3O8 material synthesized by tartaric acid assisted route and sintered at 450 °C for 3 h shows best electro-chemical performance. It shows a high initial capacity of 249 mAh g−1 and still reserves a discharge capacity of 260 mAh g−1 after 50 cycles. Moreover, in the case of tartaric assisted products, no capacity decadence is observed in 50 cycles. XRD together with TG/DTA measurements reveal that compared with citric acid assisted products, the adoption of tartaric acid as chelating agent effectively lowers the crystallization temperature of amorphous Li1+xV3O8. Therefore, precursors obtained by tartaric acid route calcinated at 450 °C for 3 h exhibit lower crystallinity and smaller grain size, which contributes to the better electrochemical performance of the cathode electrodes. From EIS measurements, the bulk resistance is reduced, which favors the intercalation and de-intercalation of lithium ions while cycling.

Lithium-ion battery cathode material Li 1+ x V 3 O 8 was synthesized by a tartaric acid assisted sol–gel method and thermally treated at 350 °C, 450 °C and 550 °C for 3 h for the formation of Li 1+ x V 3 O 8 phase. The synthesized samples were fully characterized by FTIR, TG/DTA, XRD and charge–discharge tests. Li 1+ x V 3 O 8 material synthesized by tartaric acid assisted route, followed by heat treatment at 450 °C for 3 h shows best electro-chemical performance. It shows a high initial capacity of 249 mAh g −1 and still reserves a discharge capacity of 260 mAh g −1 after 50 cycles. Moreover, for all tartaric assisted products, no capacity decadence is observed in 50 cycles. The in situ X-ray measurements reveal a two-phase transition mechanism in the lithium intercalation/deintercalation process. During lithium extraction, the structure of the delithiated compound changes from Li 4 V 3 O 8 ( x > 3.1) to the original LiV 3 O 8 phase ( x x a axis and a slight expansion along b axis are also observed.

In order to improve the electrochemical performance of the La–Mg–Ni system A2B7-type electrode alloys, La in the alloy was partially substituted by Pr and melt spinning technology was used for preparing La0.75−xPrxMg0.25Ni3.2Co0.2Al0.1 (x = 0, 0.1, 0.2, 0.3, 0.4) electrode alloys. The microstructures and electrochemical performance of the as-cast and spun alloys were investigated in detail. The results obtained by XRD, SEM and TEM show that the as-cast and spun alloys have a multiphase structure which consists of two main phases (La, Mg)Ni3 and LaNi5 as well as a residual phase LaNi2. The substitution of Pr for La leads to an obvious increase of the (La, Mg)Ni3 phase and a decrease of the LaNi5 phase in the alloys. The results of the electrochemical measurement indicate that the discharge capacity of the alloys first increases and then decreases with variation of the Pr content. The cycle stability of the alloy monotonically rises with increasing Pr content. When the Pr content rises from 0 to 0.4, the discharge capacity increases from 389.4 (x = 0) to 392.4 (x = 0.1) and then drops to 383.7 mAh/g (x = 0.4) for the as-cast alloy. Discharge capacity increases from 393.5 (x = 0) to 397.9 (x = 0.1), and then declines to 382.5 mAh/g for the as-spun (5 m/s) alloys. The capacity remaining after 100 cycles increases from 65.32 to 79.36% for the as-cast alloy, and from 73.97 to 93.08% for the as-spun (20 m/s) alloy.

In order to improve the hydrogenation and dehydrogenation performances of the Mg 2 Ni-type alloys, Mg was partially substituted by La in the alloy, and melt spinning technology was used for the preparation of the Mg 20– x La x Ni 10 ( x =0, 2, 4, 6) hydrogen storage alloys. The structures of the alloys were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM). It was found that no amorphous phase formed in the as-spun La-free alloy, but the as-spun alloys containing La held a major amorphous phase. When La content x ≤2, the major phase in the as-cast alloys was Mg 2 Ni phase, but with further increase of La content, the major phase of the as-cast alloys changed into LaNi 5 +LaMg 3 phase. Thermal stability of the as-spun alloys was studied by differential scanning calorimetry (DSC), showing that spinning rate was a negligible factor on the crystallization temperature of the amorphous phase. The hydrogen absorption and desorption kinetics of the as-cast and as-spun alloys were measured using an automatically controlled Sieverts apparatus, confirming that the hydrogen absorption and desorption capacities and kinetics of the as-cast alloys clearly increased with rising La content. For La content x =2, the as-spun alloy displayed optimal hydrogen desorption kinetics at 200 °C.

The thermal stability of the resin matrix is an important factor affecting the safety performance of fiber-reinforced bulletproof composites (FRBCs) during their service period. In this study, two kinds of waterborne polyurethanes based on polyester diol (PEDL218) and isophorone diisocyanate were synthesized; these were used as the matrix of para-aramid FRBCs. Their thermal stability and thermal decomposition behaviors in a nitrogen atmosphere were studied by dynamic thermogravimetric analysis techniques. The kinetic parameters, including the activation energy (E) and pre-exponential factor (A), were calculated by the Flynn–Wall–Ozawa, Kissinger–Akahira–Sunose, Kissinger, and Satava–Sestak methods. The results show that the cationic waterborne polyurethane with quaternary ammonium groups has better thermal stability than the anionic waterborne polyurethane with carboxylate groups. Their nonisothermal decomposition mechanisms were studied, and the kinetic parameters were also calculated; this will offer theoretical reference for the manufacturing and application of FRBCs based on waterborne polyurethane. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42374.

Li1.15V3O8 nanobelts with length 3 μm, width 200 nm and 20–50 nm in thickness are prepared on a large scale by a tartaric acid-assisted sol–gel technique. They show greater reversibility of the lithium ion insertion/extraction reaction than those synthesized without the addition of tartaric acid. After twenty cycles, the reversible lithium storage capacities of Li1.15V3O8 prepared from tartaric acid assisted and free techniques are 231.0 and 194.5 mAh/g at a current density of 30 mA g−1, respectively. Cycled at 20 mA g−1 in 1.5–4.1 V, Li1.15V3O8 nanobelts can deliver discharge and charge capacities of 297.0 and 298.4 mAh/g, respectively. Increasing the charge/discharge current density to 2400 mA g−1, the lithiation and delithiation capacities of Li1.15V3O8 nanobelts can be mantianed at 184.2 and 184.2 mAh/g, respectively. In situXRD observation reveals that the host structure of Li1.15V3O8 nanobelts will not be destroyed with a discharge process to 0.0 V at 20 mA g−1 or a short circuit for 24 h. Over-lithiation can induce the formation of an inactive compound, leading to poor electrochemical properties of Li1.15V3O8 nanobelts. The first lithiation/delithiation process in 0.0–4.1 V or 1.5–4.1 V is a reversible reaction at a current density of 60 mA g−1, and is composed of reversible single-phase structural evolutions in a high voltage region and two-phase structural transitions in a low voltage region. The electrochemical properties of Li1.15V3O8 nanobelts are poorer at the 10th cycle in 0.0–4.1 V than that obtained in 1.5–4.1 V. In situXRD results indicate that the breakdown of two-phase transition in a low voltage region is the main factor for poor cycleability. Besides, a delay of structural evolution and asymmetry lithiation/delithiation process can be observed at high rates, which may also be responsible for the deterioration of cycleability of Li1.15V3O8 nanobelts.