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Photoelectrochemical (PEC) water-splitting using solar energy holds great promise for the renewable energy future, and a key challenge in the development of industry viable PEC devices is the unavailability of high-efficient photoanodes. Herein, we designed a TiO2 model photocatalyst with nano-groove pattern and different surface orientation using low-energy Ar+ irradiation and photoetching of TiO2, and significantly improved the intrinsic activity for PEC water oxidation. High-resolution transmission electron microscopy directly manifests that the grooves consist of highly stepped surface with steps and well-crystallized. Transient absorption spectroscopy reveals the groove surface that allows for increased recovery lifetime, which ensures promoted electron-hole separation efficiency. Surface photovoltage directly shows the carrier separation and transportation behaviors, verified by selective photodeposition, demonstrating the groove surface on TiO2 contributes to electron-hole separation. This work proposes an efficient and scalable photoanode strategy, which potentially can open new opportunities for achieving efficient PEC water oxidation performance.

Facet regulation of the BiVO4 photoanode is an effective way to improve its charge separation efficiency. Herein, a BiVO4 photoanode structured by connecting a (040)-facet-oriented mono-grain layer...

A rod-like Ta3N5 thin film was synthesized by calcining a vacuum-sealed mixture of Ta metal plates and NH4Cl powder. Photoelectrochemical water oxidation results showed that an anodic photocurrent of 3.2 mA cm−2 at 1.23 V (vs. RHE) with a faradaic efficiency of unity for O2 evolution could be achieved by employing the as-prepared Ta3N5/Ta as a photoanode.

A novel and effective method to co-extrude metallic alloys is described which named Direct Extrusion and Bending-Shear Deformation. The compound extrusion plates have cracked at 290 °C and 3 mm/s. According to this phenomenon, a model was built to investigate the crack generation and development between the 6061 Al and AZ31 Mg alloy during the compound extrusion process by DEFORM-3D. The cracking behavior of the Mg/Al composite rod with a soft Mg AZ31 core and a hard Al 6061 sleeve were systematically studied to disclose the influence of microstructure on crack in the different regions. The simulation results show that the distribution of strain and velocity has significant differences due to the influence of dies structure and material properties at different locations in the same region. The experimental results show that in the same conditions, there are differences in recrystallization and texture weakening of AZ31 Mg alloys and 6061 Al alloy, which are important factors for the formation of crack. Both the Mg layer and the Al layer have a homogeneous microstructure in the region d. Keywords: AZ31 Mg alloy, 6061 Al alloy, Compound extrusion, Crack, EBSD

2,5-Diethyl-1,4-benzenedinitrile N-oxide was designed and synthesized to achieve room temperature curing of hydroxyl-terminated polybutadiene binders. The structures and properties of the four cured elastomers having different content of curing agent were investigated. The results showed that the isoxazoline rings from the reaction of nitrile N-oxide with cis-alkene are observed in the four cured elastomers. The results also revealed that the hydroxyl-terminated polybutadiene with the lowest content of curing agent showed the lowest cross-linking density and stress at break. The proper activity and steric hindrance of 2,5‑diethyl-1,4-benzenedinitrile N-oxide gave better mechanical properties and hydrophobic properties of the cured elastomers than nitrile N-oxide prepared by our previous work.

A magnesium alloy, Mg-8Al-0.5Zn-0.2Ag-0.2Mn (AQ80), was extruded by forward extrusion and twist deformation (FETD) at 370°C with 0% and 6% pre-compression. The effect of pre-compression on microstructure and texture of the AQ80 Mg alloy during FETD was systematically investigated. Compared with the 0% pre-compression FETD-ed sample, the 6% pre-compression FETD-ed sample shows a more uniform and finer microstructure and a weaker texture. The effects of pre-twinning on the microstructure and texture during FETD were also investigated. It was found that many {10–12} tension twins were implanted into the as-cast AQ80 Mg alloy by the 6% pre-compression treatment, providing sufficient nucleation sites for subsequent dynamic recrystallization. Combined with microstructure evolution analysis, it can be concluded that the texture development is strongly influenced by the twinning and basal slip during FETD extrusion.

This work investigated the effects of CeO2 contents on structure, crystallization behavior and dielectric properties of CaO–B2O3–SiO2 glass composition. The MAS-NMR results showed that B occurred as BIIIa, BIIIs and BIV species and Si presented as Q2, Q3 and Q4 units in the glasses. As the increase of CeO2 content, the relative amounts of BIV and BIIIs unit decreased while the BIIIa units increased, and the amounts of Q4 and Q2 units increased while the Q3 unit decreased. With increasing CeO2 content, the value of Tg decreased from 743 °C to 717 °C, the activation energy for CaSiO3 first increased and then decreased. For glass–ceramics samples sintered at 825 °C, all samples had the crystalline phases of CaSiO3, CaB2O4, Ca2SiO4. In addition, the samples with CeO2 content more than 1 mol% had CeO1.695 phase, which changed to be the main crystalline phase when the content of CeO2 increased up to 10 mol%. The er of the glass–ceramic samples with CeO2 content x ≤ 6 showed an ascend trend in total, and decreased sharply to 4.1 for the sample with x = 10. However, the dielectric loss tan δ would not change significantly with the increasing of CeO2 content. The samples with 1 mol% CeO2 sintered at 825 °C owned er of 5.4, tan δ of 0.9 × 10− 3, and CTE of 7.8 × 10− 6/K. The results indicated that CaO–B2O3–SiO2 with CeO2 glass–ceramics could be a potential LTCC substrate material.

The AZ31 Mg alloys were processed by 6% pre-compression and frustum shearing extrusion at various temperatures, and the microstructure, texture and mechanical properties of the resulting alloys are systematically investigated. The results show that the grain size monotonically increases from 6.4 to 12.6 μm and the texture intensity increases from 6.7 to 9.6 with the increase in the extrusion temperature. The combining effect of the pre-twinning and the frustum shearing deformation is found to contribute to the development of the weak basal texture in Mg alloys. The Mg alloy sheet produced at the extrusion temperature of 563 K exhibits excellent mechanical properties. The yield strength, ultimate tensile strength and elongation for the extruded alloys are 189.6 MPa, 288.4 MPa and 24.9%, respectively. Such improved mechanical properties are comparable or even superior to those of the alloys subjected to other deformation techniques, rendering the pre-compression and frustum shearing extrusion a promising way for further tailoring properties of Mg alloys.

A series of ZrN-Ag nano-composite films were deposited using the RF magnetron sputtering system. The microstructure, mechanical properties and tribological performances were investigated. The results showed that ZrN-Ag films were composed of face-centered cubic (fcc)-ZrN and face-centered cubic (fcc)-Ag. With the increase of Ag content, the hardness of ZrN-Ag composite film increased rapidly and then decreased rapidly. The maximum hardness value was 22.8 GPa at 6.1at.% Ag. At room temperature, the coefficient of friction (Cof.) of ZrN-Ag films were lower than the ZrN film. During 25-500°C, the Cof. of ZrN-Ag films at 29.16 at.% Ag were lower than ZrN film, while the wear rate were higher than the ZrN film. In summary, the addition of Ag improved the hardness, and decreased the Cof. of the ZrN-Ag during 25-500°C.

Incorporation of alien atoms into TiO2 is an effective means to extend its light absorption edge for utilizing solar energy sufficiently. Herein, taking rutile and anatase as precursors, respectively, Rh element was attempted to dope into TiO2 by an immersion-calcination process. The results showed that Rh species were readily immerged in the crystal structure of rutile at a temperature above 973 K, while they were constantly positioned on the surface of anatase in a separate form of Rh2O3 nanoparticle even at 1173 K. Density functional theory simulations revealed that the Rh-rutile sample owned a higher negative formation energy than Rh-anatase. Under visible light irradiation and in the presence of ascorbic acid as a sacrificial reagent, photocatalytic hydrogen evolution activity over Rh-doped rutile was about 50 times of that over Rh-doped anatase powders. The present work demonstrates the roles of the crystal phase in atom doping that eventually dominates photocatalytic activities.

Chlorhexidine (CHX)/β-cyclodextrin (β-CD) inclusion and chitosan nanoparticles containing bovine serum albumin (CS/BSA) were blended into chitosan acetic acid solution respectively or simultaneously to prepare a novel thermosensitive hydrogel dual sustained-release system. Rheological properties, release, cytocompatibility, and antibacterial activity were investigated. The results confirmed that CHX/β-CD and CS/BSA were well dispersed in the solution, and the rheological property of hydrogel was not affected. The system exhibited promising dual sustained release and cytocompatibility. Antibacterial results showed that CHX-loaded hydrogel had a desirable therapeutic effect on Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli).

The CaO–B2O3–SiO2 (CBS) glasses with addition of xLa2O3 (0 ≤ x ≤ 20 wt%) were prepared by conventional quenching method, the glass structure, phase transformation and microware dielectric properties were studied. The glass structure analysis by magic angle spinning nuclear magnetic resonance (MAS-NMR) and infrared (IR) spectroscopy indicated that [BO4] transformed into [BO3] and the proportion of Si–O–Si bridge oxygen bond in [SiO4] tetrahedrons decreased obviously with the addition of La2O3. The differential thermal analysis (DTA) revealed that the CBS glass system kept better glass-forming ability and the transition temperature (T g) decreased from 743 to 724 °C after addition of La2O3. As the content of La2O3 increases, the crystallization tendency of CaB2O4 is suppressed, while that for Ca2SiO4 is promoted. With appropriate content of La2O3 (5 wt%), the sample possess excellent dielectric properties (e r ≈ 4.1, tanδ ≈ 1.7 × 10−3 at 15 GHz). The variations of dielectric properties are believed to be appreciably associated with the relative content of the phases present.

The aim of the present work is to investigate the effects of SiO2 content on the structure of CaO–B2O3–SiO2–Al2O3–ZnO glass using the MAS-NMR, the fourier transform infrared spectrometer and differential scanning calorimetry (DSC). The results showed that the majority of Al existed in fourfold coordination and Zn acted as glass modifier in glass structure. With the increasing of SiO2 content, the relative amount of BIII units decreased while the BIV units increased and the proportion of Si–O–Si bridge oxygen bond in [SiO4] tetrahedrons increased obviously. The DSC curves revealed that the glass transition temperature increased from 732 to 773 °C with the increasing of SiO2 content, indicating that SiO2 generating more bridge oxygen can increase the degree of polymerization of glass structure.

The aim of the present work is to investigate the effects of Al2O3 content on both the structure and crystallization behavior of CaO–B2O3–SiO2 (CBS) glass composition using NMR, FT-IR and DSC. The density experimental results showed that the density (ρ) of glasses decreased linearly with increasing Al2O3 content, while the molar volume (Vm) of the glasses increased linearly. The NMR revealed that the Al occurred in the forms of AlIV, AlV and AlVI units. With the increasing Al2O3 content, the amount of Al species show little change, the relative amount of BIIIa and BIIIs units increases while the BIV units decrease, and the Q4 structural units increases clearly but the Q3 decreases. Further, crystallization peaks of CBS glasses shift to higher temperatures, indicating that Al2O3 addition can suppress crystallization of CBS glasses.

Ce-based materials have gained considerable prominence in catalysis as a type of the most valuable material for various applications ranging from automotive emission control to CO2 and water splitting. We here report a novel type-II CeO2/CeF3 composite, composed of two paradigms of Ce-based binary compounds, prepared by a facile one-step in-situ hydrothermal method, and explore its potential as a photocatalyst for solar energy conversion. Primarily, the morphologies, particle size and microstructures of CeO2/CeF3 composite can be modulated by the volume ratio of ethanol to water in the precursor solution. The photocatalytic activities firstly increase to a maximum and then decrease with the increased amount of ethanol. The hybrid CeO2/CeF3 particles with large size and polyhedron morphology exhibit superior photocatalytic activity, having a high rate constant k of MB decomposition about 7.6 times faster than that of the lowest one. A multiple synergetic mechanism in CeO2/CeF3 composite, which is featured by obvious promoted separation of photogenerated electrons and holes at the type-II heterojunction interfaces and in particular between the different facets of microcrystals, and the highly reactive facets exposed, has been proposed to account for its distinguished photocatalytic activity. This work provides some new insights for the synthesis and optimization of novel rare earth Ce-based composite photocatalyst with high photocatalytic performance.

The Ba2+ doped ceramics of Ca1−xBaxCu3Ti4O12 (x = 0.005, 0.01, 0.03, 0.05 and 0.1) were sintered via conventional solid-state reaction at 1050 °C for 8 h in air. The microstructure and electric properties of Ba2+ doping ceramics were investigated. The lattice parameters of Ca1−xBaxCu3Ti4O12 (CBCTO) ceramics decreased with the Ba2+ doping, and Ba1.31Ti8O16 as secondary phase was confirmed at x = 0.1. The doping of Ba2+ resulted in uniformly distribution of small size grain (~4 μm). All the doped samples showed lower value of dielectric constant than CaCu3Ti4O12 (CCTO), due to low resistivity of the grain boundary with the Ba2+ doped samples. The nonlinear coefficient and breakdown field were significantly enhanced by Ba2+ doping.

(CoxNi1−x)0.85Se nanostructures (NSs) with different shapes (i.e., sheet-like, flower-like, and urchin-like) were synthesized by a sacrificial template method. As far as we know, this paper may be the first work that used (CoxNi1−x)0.85Se NSs as catalysts for reduction of 4-nitrophenol (4-NP) by NaBH4 in aqueous solution.

Lead-free (1−x)(Ba 0.85 Ca 0.15 )(Ti 0.9 Zr 0.1 )O 3 -xBa(Mg 1/3 Nb 2/3 )O 3 (BCZT-BMN) (x=0.05, 0.10, 0.15, 0.20) ceramics were fabricated by conventional solid-state reaction. The effect of Ba(Mg 1/3 Nb 2/3 )O 3 (BMN) addition on structure and electrical properties of BCZT ceramics were studied. The results show that the BCZT-BMN ceramics possess rhombohedral phase at x=0.05, orthorhombic and rhombohedral phases coexist at x=0.10, 0.15, 0.20. High Curie temperature (T c ) maintained over 300 °C at the compositions x=0.05 and 0.10. The samples at x=0.05 exhibit good ferroelectric properties. This work offers an effective way to adjust the range of service temperature of BCZT by BMN addition.

In this reported work Ni-riched NiO-Co3O4 sheet-like nanocomposites (SNCs) were obtained through a facile solvothermal method in a mixed solvent and subsequently calcinated in air. Galvanostatic charge-discharge measurement revealed that the Ni-riched NiO-Co3O4 SNCs electrode has an impressive specific capacitance as high as 836 F g−1 at 4 A g−1 in 3 M KOH solution. The as-obtained Ni-riched NiO-Co3O4 SNCs product showed a weak cycling stability, but the higher capacitance (424 F g−1) was retained after 1000 cycles at 4 A g−1.

The magnetocaloric effects in Mn1.3Fe0.7−xCoxP0.46Si0.54 compounds (x = 0, 0.025, 0.05 and 0.1) were investigated systematically. X-ray diffraction shows that the compounds crystallize in the Fe2P-type hexagonal structure with space group P-62m symmetry. Magnetic measurements show that the paramagnetic-ferromagnetic transition temperatures range from 247 to 298 K. The maximal magnetic entropy changes in the Mn1.3Fe0.7P0.46Si0.54 compound reaches 8.3 J/kgK for a field change from 0 to 1.5 T. The thermal hysteresis of these compounds is less than 3 K. The maximum adiabatic temperature change is 2.2 K in Mn1.3Fe0.7P0.46Si0.54 and Mn1.3Fe0.65Co0.05P0.46Si0.54 compounds for a field change from 0 to 1.48 T, indicating this material system has potential for room-temperature magnetic refrigeration applications.

The crystallinity of wood has an important effect on the physical, mechanical and chemical properties of cellulose fibers. Crystallinity of larch plantation wood was investigated with near infrared spectroscopy and multiple linear regression. Five typical wave lengths were selected to establish prediction model for wood crystallinity. Full-cross validation was applied to the model development. The model performance is satisfied with prediction correlation coefficient of 0.896 and bias of 0.0004. The results indicated that prediction of wood crystallinity with near infrared spectroscopy and multiple linear regression is feasible, which provides a fast and nondestructive method for wood crystallinity prediction.

Earlywood microfibril angle (MFA) was determined at each growth ring from disks at breast height (1.3 m) from 6 dahurian larch (Larix gmelinii. Rupr.) trees grown in northeastern China. Significant variation in microfibril angle was observed among growth rings. MFA at breast height varied from 7.5°to 21.5°between growth rings and showed a descreasing trend from pith to bark for each tree. A second order polynomial equation with linear mixed-effects was used for modeling earlywood MFA. The LME procedure in S-Plus is used to fit the mixed-effects models for the MFA data. The results showed that the polynomial model with three random parameters could significantly improve the model performance. The fitted mixed-effects model was also evaluated using a separate dataset. The mixed model was found to predict MFA better than the original model fitted using ordinary least-squares based on absolute and relative errors.

It was found previously by us that the compositions of industrial alloy specializations are related to the chemical short-range ordering in solid solution alloys, which is in accordance with the cluster-plus-glue-atom model. This model identifies short-range-ordered chemical building units in solid solutions, which the specific alloy compositions rely on. For instance, substitutional-type FCC solid solution alloys are described by cluster-based units formulated as [cluster](glue atom)16, where the bracketed cluster is the nearest-neighbor coordination polyhedral cluster, cuboctahedron in this case, and one-to-six glue atoms occupy the inter-cluster sites at the outer-shell of the cluster. In the present paper, we investigate the atomic configurations of these local units in substitutional-type FCC solid solutions by exhausting all possible cluster packing geometries and relevant cluster formulas. The structural model of stable FCC solid solutions is first reviewed. Then, solute distribution configurations in FCC lattice are analyzed by idealizing the measured chemical short-range orders within the first and second neighborhoods. Two key assumptions are made with regards to the cluster distribution in FCC lattice. First, the clusters are isolated to avoid the short-range orders from extending to longer range ones. Second, the clusters are at most separated by one glue atom to confine the inter-cluster distances. Accordingly, only a few structural unit packing modes are identified. Among them, the configurations with glue atoms 0, 1, 3, and 6 show good homogeneities which indicate special structural stabilities. Finally, compositions of FCC Cu-Zn (representative of negative enthalpy systems) and Cu-Ni (positive enthalpy ones) industrial alloys are explained by using the structure units of cluster packing and the cluster formulas, expressed as [Zn-Cu12]Zn1-6 and [Zn-Cu12](Cu, Zn)6, where the cluster is Zn-centered, shelled with Cu atoms, and glued with one to six Zn or with a mixture of six Cu and Zn. In particular, the formula [Zn-Cu12]Zn6, with the highest Zn content, corresponds to the solubility limit in Cu-Zn alpha phase zone, which is also the composition of the specification C27400. The Cu-rich Cu-Ni alloys are explained by cluster formulas [Cu-Cu12](Cu, Ni) 6, where the cluster is Cu centered and glued with a mixture of six Cu and Ni. The Ni-rich Monel alloy is explained by cluster formulas [Ni-Ni12](Cu5Ni)-[Ni-Ni12]Ni6. The present work provides a new approach to alloy composition explanation and eventually to alloy composition design from the perspective of short-range ordering in solid solutions.

Diode-pumped Nd:YAG lasers are promising sources of the new optical frequency standards at 532 nm that were recommended recently in the 9th CCDM. Molecular iodine has several strong absorption lines at the second harmonic of Nd:YAG laser near 532 nm, thus providing an absolute reference for frequency stabilization. In general, the 532 nm laser sources used in iodine-stabilized systems are commercial monolithic lasers, which are compact, efficient, and reliable, but are also expensive and complicated. Recently, we have frequency stabilized a self-developed single-frequency Nd:YAG-KTP laser to the Doppler-broadened (instead of Doppler-free) lines of iodine. That was the first time to stabilize a 532 nm laser to an absolute reference in China. Due to its concise structure, low cost, and the ability to resist more disturbance, the laser system is attractive in some certain industrial applications that require an absolute frequency reference but not very high stability.

The structural and magnetocaloric properties of Mn1.35Fe0.65P1−xSix compounds are investigated. The Si-substituted compounds, Mn1.35Fe0.65P1−xSix with x = 0.52, 0.54, 0.55, 0.56, and 0.57, are prepared by high-energy ball milling and the solid-state reaction. The X-ray diffraction shows that the compounds crystallize into the Fe2P-type hexagonal structure with space group P2m. The magnetic measurements show that the Curie temperature of the compound increases from 253 K for x = 0.52 to 296 K for x = 0.56. The isothermal magnetic-entropy change of the Mn1.35Fe0.65P1−xSix compound decreases with the Si content increasing. The maximal value of the magnetic-entropy change is about 7.0 J/kgK in the Mn1.35Fe0.65P0.48Si0.52 compound with a field change of 1.5 T. The compound quenched in water possesses a larger magnetic entropy change and a smaller thermal hysteresis than the non-quenched samples. The thermal hysteresis of the compound is less than 3.5 K. The maximum adiabatic temperature change is about 1.4 K in the Mn1.35Fe0.65P0.45Si0.55 compound with a field change of 1.48 T.