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Metal atoms were deposited on an Si (111)-7 × 7 surface, and they were adsorbed with alcohol gases (CH3OH/C2H5OH/C3H7OH). Initially, CnH2n+1OH adsorption was simply used as an intermediate layer to prevent the chemical reaction between metal and Si atoms. Through scanning tunneling microscopy (STM) and a mass spectrometer, the CnH2n+1OH dissociation process is further derived as the construction of a surface quasi-potential with horizontal and vertical directions. With the help of three typical metal depositions, the surface characteristics of CH3OH adsorption are more clearly presented in this paper. Adjusting the preheating temperature, the difference of thermal stability between CH3O– and H+ could be obviously derived in Au deposition. After a large amount of H+ was separated, the isolation characteristic of CH3O– was discussed in the case of Fe deposition. In the process of building a new metal-CH3O–-H+ model, the dual characteristics of CH3OH were synthetically verified in Sn deposition. CH3O– adsorption is prone to influencing the interaction between the metal deposition and substrate surface in the vertical direction, while H+ adsorption determines the horizontal behavior of metal atoms. These investigations lead one to believe that, to a certain extent, the formation of regular metal atomic structures on the Si (111)-7 × 7-CH3OH surface is promoted, especially according to the dual characteristics and adsorption models we explored.

Scanning tunneling microscope results showed that Au and Fe atoms were steamed on the Si (111)-(7 × 7) substrate surface, with or without the step region. The experimental comparison proved that the induced effect of the step region is a controllable process, which CH3OH can adjust. In this paper, the latest progress on the dynamic phenomenon on the step region is discussed, including three deposition types: strong deposition, weak deposition, and the new quasi deposition. With a relatively weak interaction between Au and Si atoms, the linearity of the weak deposition is present in the step region. In contrast, Fe atoms tend to form a strong deposition along the boundary line between the flat and step regions. Different depositions correspond to different surface potential energy: a newly formed surface is stabilized by a quasi-potential made by breaking, and a metal atomic structure can be stabilized by forming several quasi depositions. After discussing the good adsorption properties, CH3OH can be used as an intermediate layer on the step region. As an important result of quasi deposition, a regular linear Fe cluster structure is created, which is perpendicular to the boundary line.

Mg-based alloys were prepared by rapid solidification of twin roll casting (TRC) which shows that the Mg-RE alloy expressed the quasi-amorphous phased and fine crystalline phase dual-phase material. Corrosion behavior of Mg-Based alloy in 3.5% NaCl solution after 48h immersion and mechanical properties were investigated. The result show that The Mg-RE alloy strip exhibited good corrosion resistance and higher ultimate tensile strength and elongation comparing to the AZ31 alloy strips. The elongation of Mg-RE alloy strip is also high than the AZ91 and ZK61 under powder metallurgy processing. These indicate that Mg-RE alloy produced by our method has a better ductility. This may due to the special microstructure of the Mg-RE alloy forms, i.e., quasi-amorphous phase plus fine crystalline phase dual phase state.

In this study, magnesium alloy AZ31 was successfully welded with aluminum alloy 6061 by diffusion bonding method. In addition, annealing process was applied to refine micro-structure and improve mechanical property. Microstructure and elemental distribution of interface were investigated with Scanning Electron Microscope (SEM) and Electron Probe Micro Analyzer (EPMA). Furthermore, experiments on diffusion bonded specimens with the usage of Transmission Electron Microscope (TEM) were carried out. At last, tensile strength was measured. It can be obtained that the width of diffusion layers increase with the increasing annealing temperatures. Elemental distribution of specimens with annealing were more uniform than that without annealing. The intermetallic compounds in diffusion layers are Al3Mg2 and Al12Mg17, their crystal structure are respectively face-centered cubic (fcc) and body-centered cubic (bcc). What’s more, tensile strength turns to be strongest after annealing at 250°C.

This study proposed the new method of preparing Mg-based composite by mixed powder Ni and Ti onto the surface of pure Mg ingot. The prepared method caused that hydrogen absorbing phase Mg2Ni and catalytic phase NiTi generated and distributed regularly. The pure Mg ingot as the center and the powder Ni and Ti as cladding material on the surface were formed and sintered, in which the temperature range of generated alloy phase Mg2Ni and NiTi was confirmed at first; according to the temperature range, the size of Mg2Ni and NiTi crystal grains at 650°C and 850°C were analyzed and compared, respectively; The size of Mg2Ni alloy phase at the surface and center was calculated by comparing the atomic radius of Ni, Ti to confirm that Mg2Ni distributed on the surface due to the atom Ti replaced the atom Ni in Mg2Ni to generate the alloy phase NiTi; the capacity of the hydrogen desorption reached 4wt% within 5min. The disadvantages that easy to chalking and difficult to activate in the conventional method were avoided and achieved the application of the multilayer composite material in hydrogen storage field.

In this study, Mg-based alloys were prepared by rapid solidification of twin roll casting (TRC), then microstructure and element distribution were investigated respectively with Scanning Electron Microscope (SEM) and Electron Probe Micro Analyzer (EPMA). What’s more, in order to analyze microstructure and crystal structure of Mg-based alloys, experiments on specimens with the usage of X-ray diffraction (XRD) and Transmission Electron Microscope (TEM) were also carried out. At last, the designed Mg-Re magnesium alloy with quasi-amorphous phase plus fine crystalline phase dual phase microstructure produced with our rapid solidification of TRC process. The rapid solidification process realized with a faster casting speed and a thinner roll gap that does not need any anther additional devices and vacuum environment. EPMA results and TEM analyses show that the quasi-amorphous phase has a high concentration in Al and RE element. There are quasi-amorphous phase in the middle of Mg-Re alloy cross section surrounded by dendrites phase and normal crystals. Acknowledgement. This work was supported by Cooperative Research and Development Center for Advanced Materials (CRDAM) funded by the Institute for Materials Research (IMR), Tohoku University (Project Number 18G0042).

Purpose: In this study, pore size and porosity distribution of porous Ti-6Al-4V scaffolds (pTi) were controlled by 3D printing. The effects of pore size distribution at a constant porosity, or porosity distribution at a constant pore size pertaining to functions of adhesion, proliferation, and differentiation of the mouse embryonic osteoblast precursor (MC3T3-E1) cells were researched separately. Methods: 3D printing was used to design five groups of pTi, designated as PS300/HP, PS300/LP, PS500/HP, PS500/LP, and PS800/HP based on pore size and porosity distribution. MC3T3-E1 cells were cultured on pTi, and non-porous Ti-6Al-4V samples (npTi) were prepared as control. The pTi was characterized with the scanning electron microscopy (SEM). MC3T3-E1 cells were stained via AlamarBlue assay and viability and proliferation analyzed. The mRNA levels of alkaline phosphatase (ALP), osteocalcin (OCN), collagentype-1 (Col-1), and runt-related transcription factor 2 (Runx2) in MC3T3-E1 cells were analyzed by real-time PCR analysis. Results: The average pore size and porosity of pTi were recorded as (301 ± 9 μm, 58.8 ± 1.8%), (300 ± 9 μm, 43.4 ± 1.3%), (501 ± 11 μm, 58.3 ± 1.2%), (499 ± 12 μm, 42.7 ± 1.1%), and (804 ± 10 μm, 58.9 ± 1.3%), respectively. SEM images confirmed active attachment of cells and oriented with the direction of metal rod after pTi/MC3T3-E1 co-culture for 3 and 7 days. In addition, MC3T3-E1 cells grown on the PS800/HP displayed significantly higher proliferation compared with each group after 3 days incubation ( p < 0.05). Moreover, cells showed some degree of proliferation in all groups, with the highest value recorded for PS800/HP after culture for 7 days ( p < 0.05). The gene expression pattern of ALP, OCN, Col-1, and Runx2 confirmed that these were down-regulated when pore size increased or porosity decreased of pTi ( p < 0.05). Conclusion: The pTi facilitated the adhesion and differentiation of osteoblast when pore size decreased or porosity increased. The scaffold model resembles physical modification with porous structures, which has potential application in the surface modifications of Ti implant.

Aim to greatly enhance the magnetic performance, room temperature nitriding experiments were implemented on the existing linear Fe clusters. Firstly, the dissociation of CH3OH adsorption process was deducted in detail, which laid a good foundation for the better use of surface quasi-potential. Further to solve the coming problems like weak linearity and low nitriding effect, atomic layers of Fe deposition are confirmed as the key to NH3 dissociation process (at room temperature). Specifically, the higher Fe atomic layer contacted by NH3, the weaker influence of surface quasi-potential. With the introduction of Ar, Fe cluster structure could be precisely controlled at single atomic layer, result in good NH3 dissociation and nitriding efficiency. Combining with magnetic performance result, the density of residual magnetization is improved from 1.5E−0.5 emu to 7.0E−0.5 emu, forming an obvious linear structure.

Poly(methyl methacrylate)/expanded graphite (PMMA/EG) composites are prepared using water-assisted mixing extrusion (WAME) technique. Scanning and transmission electron microscopy micrographs show that the EG exhibits better exfoliation and dispersion in the composite samples prepared with water injection than that in those without water injection. More EG layer networks and stronger PMMA-EG interfacial interaction are formed in the composite samples prepared with water injection, which are confirmed by the results of the FTIR and rheological measurements and the linear fits of experimentally obtained tensile yield stresses. The composite samples with well exfoliated and dispersed EG layers exhibit higher thermal conductivity and mechanical properties, which are ascribed to lower interfacial thermal resistance and stronger interfacial interaction, respectively. Finally, a mechanism for promoted EG exfoliation and dispersion in the PMMA matrix during the WAME is interpreted by analyzing the combined effect of injected high-pressure water with the shear force provided by the extruder screw.

A large reduction rolling process was used to obtain complete dynamic recrystallization (DRX) microstructures with fine recrystallization grains. Based on the hyperbolic sinusoidal equation that included an Arrhenius term, a constitutive model of flow stress was established for the unidirectional solidification sheet of AZ31 magnesium alloy. Furthermore, discretized by the cellular automata (CA) method, a real-time nucleation equation coupled flow stress was developed for the numerical simulation of the microstructural evolution during DRX. The stress and strain results of finite element analysis were inducted to CA simulation to bridge the macroscopic rolling process analysis with the microscopic DRX activities. Considering that the nucleation of recrystallization may occur at the grain and R-grain boundary, the DRX processes under different deformation conditions were simulated. The evolution of microstructure, percentages of DRX, and sizes of recrystallization grains were discussed in detail. Results of DRX simulation were compared with those from electron backscatter diffraction analysis, and the simulated microstructure was in good agreement with the actual pattern obtained using experiment analysis. The simulation technique provides a flexible way for predicting the morphological variations of DRX microstructure accompanied with plastic deformation on a hot-rolled sheet.

STM results showed that Fe atoms were deposited on a Si(111)-7 &times, 7 reconstructed surface, which was saturated with CH3OH molecules. Fe atomic linear structure was composed of stable clusters and in-situ observed by the scanning tunneling microscopy (STM). The aim to improve its application of magnetic memory material, both formation process and models, has been explored in this paper. By combining surface images and mass spectrometer data, an intermediate layer model was established. In terms of thermal stability, the most favorable adsorption sites of CH3OH were further explored. After that, Fe atoms were deposited on the Si(111)-7 &times, 7-CH3OH surface, forming a linear cluster structure. On the one hand, a new Fe cluster model was put forward in this paper, which was established with height measurement and 3D surface display technology. This model is also affected by the evaporation temperature, which can be consistent with the atomic stacking pattern of face centered cubic structures. On the other hand, the slight height change suggested the stability of linear structures. Even in the condition of thin air introduction, Fe cluster showed a good performance, which suggested the possibility of magnetic memory application in the future. These investigations are believed to have, to a certain extent, increased the probability of forming Fe linear clusters on the surface of silicon substrate, especially according to the models and surface technology we adjusted.

Effective hemostasis is vital to reduce the pain and mortality of patients, and the research and development of hemostatic materials are prerequisite for effective hemostasis. Chitosan (CS), with good biodegradability, biocompatibility and non-toxicity, has been widely applied in bio-medicine, the chemical industry, the food industry and cosmetics. The excellent hemostatic properties of CS have been extensively studied. As a result, chitosan-based composite hemostatic materials have been emerging. In this review, the hemostatic mechanism of chitosan is briefly discussed, and then the progress of research on chitosan-based composite hemostatic materials with multiple forms such as films, sponges, hydrogels, particles and fibers are introduced. Finally, future perspectives of chitosan-based composite hemostatic materials are given. The objective of this review is to provide a reference for further research and development of effective hemostatic materials.

Understanding the chemical evolution at the interface of organic light-emitting diodes (OLEDs) under working conditions is critical for addressing device failure and further improving performance. In this work, an in-operando approach was developed employing synchrotron-based X-ray absorption spectroscopy (XAS) to investigate the electronic structures and chemical degradation mechanisms of a model tris(8-hydroxyquinoline) aluminum (Alq3)-based OLED device under working condition. The results identify that Mg atoms from the electrode migrate into the Alq3 organic layer under a potential bias and replace Al atom sites, forming the unstable Mgq3 species which lead to device degradation. The findings from the classic and simple model device elucidate the degradation mechanisms occurred at the interface of OLED devices, which may facilitate the development of more efficient and stable OLED devices with complex structures.

High entropy oxide (HEO) is a new-type inorganic material composed of multiple principle metal elements with a single-phase structure and is proved to display many potential unexpected properties such as high structural stability and superionic conductivity. Herein, a novel spinel-structured high entropy oxide (FeCoNiCrMn)3O4 is prepared by high-temperature solid state reaction and evaluated as anode for lithium-ion batteries (LIBs). In-situ high-temperature X-ray diffraction (HT-XRD) is used to reveal structure evolution of mixed oxides with the calcination temperature increase and a single-phase spinel-structured (FeCoNiCrMn)3O4 is obtained at 900 °C. The effect of temperature on structure and electrochemical performance of HEO were investigated, and the HEO-900 anode with commercial mass loading exerts higher capacity (discharge/charge, 1034/680 mAh g−1) and better rate capability (182 mAh g−1 at 2 Ag-1) than HEO-950 and HEO-1000 for its moderate particle size, and all the three samples show excellent cycling stability. Ex-situ XRD and transmission electron microscope are applied to unravel the lithium-storage mechanism of (FeCoNiCrMn)3O4, an amorphization reaction process occurs during the initial discharging and the amorphous structure is maintained in subsequent cycles. The synergetic effect of multiple metal cations with different radius, valence states and reaction potentials and entropy stabilization effect make the HEO display a superior electrochemical performance in LIBs. This work provides a new concept to design multi-element transition metal oxide anode materials by high entropy strategy.

Hierarchical carbon nanotubes (CNTs) and graphene nanosheets (GNs) supported MnO 2 nanoneedles have been synthesized through a facile chemical-wet route without any further thermal treatment. The electrochemical capacitive performances of MnO 2 -based composite electrodes are analyzed using cyclic voltammetry, galvanostatic charge–discharge cycling, and impedance spectroscopy. It is found that the electrochemical utilization of MnO 2 nanoneedles is effectively enhanced by the synergistic effect that combines the MnO 2 crystals and the carbon supports, raising more active sites available for formation of charge transfer and electric double-layer in the hybrid architecture. The maximal specific capacitance of capacitors attains as high as 440 F g −1 . The specific energy of MnO 2 /GN capacitor can reach as high as ∼40 Wh kg −1 at a specific power of 20,000 W kg −1 , analyzed by the Ragone plot. The improved performance can described to the fact that the robust design of hybrid structure is capable of (i) maximizing the utilization of MnO 2 nanoneedles and (ii) leading to fast chemical reaction kinetics including ionic electro-sorption and charge transfer. This method provides a straightforward approach to deposit MnO 2 onto GNs as electrode materials for various energy-storage devices.

A diffusion/transformation coupled model has been developed which combines finite difference (FD) model with a phenomenological model. The composition of the different iron-nitrogen(Fe-N) hardening phase can be regard as a function of nitriding time and nitrogen concentration. The diffusion model and transformation model are linked by the limiting nitrogen solubilities and the effective diffusion coefficients. The effect of alloy elements (Cr, Mo, Mn, V, Ni etc.) is considered by introducing an alloy coefficient for limiting nitrogen solubilities and diffusion coefficient. The diffusion/transformation model can predict nitrogen concentration, phase composition and hardness distribution. The model is employed to simulate the nitriding process of SCr420H low-alloy steels. The simulated nitrogen concentration and hardness profiles are consistent with the measured ones. In addition, the predicted depth distributions of iron-nitrogen phase agree well with the available experimental results. Therefore, the comparison shows the reliability of the coupled model. It can be applied to improve the nitriding process parameters.

The purpose of this study was to examine the microstructure and texture evolution of a twin roll cast AZ31 magnesium alloy after multi-pass warm rolling in a temperature range from 233 to 248 °C. Reduction per pass was kept constant at about 10% and the total reduction was 98.2% after 33 pass steps with a change of sheet thickness from initially 2.85 mm down to 50 μm. The rolled sheets exhibited a fairly strong basal texture with an intensity of 17–21 multiples of random distribution (MRD) in the initial stages (with a thickness above 0.47 mm) due to the lower rolling temperatures. The basal texture intensity decreased to 13–15 MRD in the later stages (with a thickness below 0.3 mm) due to the occurrence of dynamic recrystallization at slightly higher rolling temperatures to balance out the demand of rolling force. The basal pole in the thicker sheets spread slightly along ±TD with an ellipse shape mainly due to the activation of 〈 a 〉 prismatic slip and the occurrence of shear bands, while the splitting of basal pole in the thinner sheets was observed to be along the RD with a tilting angle of about ±10°. This was attributed to the activation of 〈 a + c 〉 pyramidal slip. The average grain size in the thinner sheets in the later stages during the multi-pass rolling decreased almost linearly with increasing number of rolling steps. This could be explained via a change in the Zener–Hollomon parameter which was associated with the strain rate affected by the sheet thickness during rolling at a constant percent reduction.

Fe 76 Si 9.6 B 8.4 P 6 amorphous powder was produced by gas atomization. Next, bulk amorphous powder discs were prepared by pressing a mixture of Fe 76 Si 9.6 B 8.4 P 6 amorphous powder and a small amount of SiO 2 powder using the spark plasma sintering technique. The resulting bulk amorphous powder cores were obtained from the compacted discs using an electrical spark erosion machine. The powder core with 5 mass% SiO 2 shows both high saturation magnetization of 1.41 T and good soft magnetic properties, 23 A/m for coercive force and 117 for effective permeability at 1 kHz. The core also exhibits much lower core loss than silicon steels or the powder core without SiO 2 , only 71 W/kg at a maximum magnetic induction of 0.2 T with a frequency of 10 kHz. The low core loss is due to a SiO 2 insulator layer forming on the surface of the alloy powder that can effectively reduce the eddy current and consequently reduce the core loss.

All-inorganic (CsPbX3) perovskites by replacing the volatile organic components with cesium cations allow extending the long-term thermal stability of perovskite solar cells (PeSCs) vs their organic–inorganic hybrid counterparts. However, the stability of α-CsPbI3 and α-CsPbI2Br still remains to be improved. In this work, we incorporate redox-inactive samarium acetylacetonate [Sm(acac)3] into CsPbI2Br to fabricate CsPbI2Br perovskite thin films. It is evidenced that Sm3+ not only partially substitute the Pb2+ sites to yield slightly contracted perovskite lattice but also modulate the perovskite growth and passivate the NiOx/CsPbI2Br interface. As a result, CsPbI2Br PeSCs based on stoichiometric and optimal Sm(acac)3 doping (0.15 mol. %) of CsPbI2Br show excellent photovoltaic metrics with a champion power conversion efficiency (PCE) of 12.86%. Moreover, the CsPbI2Br PeSCs exhibit enhanced thermal stability upon incorporation of Sm(acac)3, which retains 90% of their original PCE under heating at 85 °C for 200 h.

The construction of acid-base resistant materials for elimination of organic contaminations in water under the sunlight conditions is very important for the protection of our living surroundings. Metal-organic frameworks (MOFs) are promising candidates for photocatalytic applications, but many of them suffer from poor framework stability under the acidic or basic conditions. In this study, by using a bifunctional ligand 4-(4-carboxyphenyl)-1,2,4-triazole (HCPT) featuring both carboxylate and azole groups, a new polyoxometalate-based MOF formulated as {[Cu8Cl5(CPT)8(H2O)4](HSiW12) (H2O)20(CH3CN)4}n (1) has been prepared via a solvothermal approach. Complex 1 shows a 3D 2-fold interpenetrating scu-type network based on the four-connected {Cu2(CO2)4} and eight-connected {Cu4Cl}7+ clusters, and could be stable in a wide range of pH values f0 to 14). Apart from its excellent framework stability, complex 1 shows a high photocatalytic efficiency for the degradation of rhodamine B (RhB) by visible light irradiation and nearly 97% of the RhB was degraded within 70 ​min. To our knowledge, complex 1 represents the first case of polyoxometalate-based MOFs constructed from the mixed-cluster units.

In the case of methylammonium lead halide (MAPbH3) perovskite solar cells, the indium tin oxide (ITO) film has been widely used as the transparent electrode. In the preparation process and service process of MAPbH3 perovskite solar cells, the MAPbH3 perovskite layer can decompose into the methyl, amino, methylammonium, halide ion/group, etc. Thus, the diffusion of ammonia ion/group into ITO film is inevitable, which can seriously deteriorate the electrical property of ITO transparent electrode. In this study, the ITO films with and without (100) preferred orientation are bombarded by a low-energy ammonia (NHx) ion beam. After the bombardment, the electrical properties of ITO film without preferred orientation are deteriorated seriously, especially for carrier concentration, which is deteriorated down to an extent of about 5–6 orders of magnitude. The bombardment of low-energy NHx ion/group has little influence on the electrical properties of ITO film with (100) preferred orientation. Such phenomena can be explained by the following reasons. Based on XPS measurement results, the low-energy NHx ion/group diffuses into the ITO film surface after the bombardment. In the diffusion process, the low-energy NHx ion/group is mainly bonded with O in ITO lattice, which results in the formation of In/Sn—O—N bond. Based on the crystal structure of ITO, the (100) lattice of ITO consists of In/Sn, and the calculated value of surface energy \begin{document}$ {\gamma }_{\left\{100\right\}/\left\{010\right\}/\left\{001\right\}} $\end{document} = 1.76 J/m2. While the (110) and (111) lattices of ITO consist of In/Sn/O, in which the O atom percent on (110) and (111) lattices are 56 at.% and 25 at.% respectively. Besides, the calculated values of surface energy \begin{document}$ {\gamma }_{\left\{110\right\}/\left\{101\right\}/\left\{011\right\}} $\end{document} and \begin{document}$ {\gamma }_{\left\{111\right\}} $\end{document} are 1.07 and 0.89 J/m2, respectively. Combining the XPS measurement results and crystal structure of ITO, it can be understood that in the diffusion process of low-energy NHx ion/group into ITO film without preferred orientation, lots of In/Sn—O—N bonds are formed in the ITO lattices, which are rich in O and have lower surface energy \begin{document}$ \gamma $\end{document}. Then, after the low-energy NHx ion/group bombardment, the electrical properties of ITO film without preferred orientation are deteriorated seriously. On the contrary, because of the absence of O and the highest surface energy \begin{document}$ \gamma $\end{document}, it is hard for the low-energy NHx ion/group to diffuse into ITO (100) lattice. Then, after the low-energy NHx ion/group bombardment, the electrical properties of ITO film with (100) preferred orientation have little change. With all results, the ITO film with (100) preferred orientation can be an ideal candidate for transparent electrode in MAPbH3 perovskite solar cells.

A mathematical model has been developed to simulate the nitriding process of plain carbon steel, considering the simultaneous diffusion of nitrogen in different iron-nitrogen (Fe-N) phases and the precipitation dynamics of γ’e and iron-nitride. The model can predict the distribution of nitrogen concentration, volume fraction of Fe-N phases and hardness. Furthermore, a finite element method (FEM) post-process technology is presented to avoid the limit of FEM mesh improvement and time-saving. The uniform-sum-division algorithm is adopted as local refinement algorithm (LRA) of meshes. The modified inverse distance weighting (IDW) method is used to interpolate the FEM simulated results. Then, the nitriding model and post-process technology are incorporated within the framework of the developed FEM code COSMAP (COmputer Simulation of MAnufacturing Process) based on metallo-thermo-mechanical theory. In order to validate the nitriding model and FEM post-process technology, the nitriding process of S30C steel is modeled by COSMAP software. The simulated distributions of nitrogen content and hardness are consistent with the measured ones. In addition, the simulated results at different mesh size are compared for two-dimensional model. It is indicated that the interpolated results agree well with the simulated results of fine mesh model and the experimental ones.Keywords: finite element, nitriding, S30C, iron nitride, inverse distance weighting

Artificial media were used to enrich microbe and improve the water resource quality; therefore trace quantity organic pollutants of 1,2,4-trichlorobenzene were biodegraded. The result of the test showed that, after domestication, the microassociation enriched in the assembled medium could remove corresponding trace quantity organic pollutants in some concentration. When the temperature was 30 degree centigrade, and the pH was between 6 and 9, the effect about the removal on trace-quantity-organic pollutants water was the best. A strain of bacteria that could degrade 1,2,4-trichlorobenzene was separated, and its degradation mechanism to 1,2,4-trichlorobenzene was studied. At the same time, the congener trace quantity organic pollutants could be biodegraded. Biofilm after domestication can effectively degrade a certain concentration range of three trichlorobenzenes and the removal effect of HRT = 7 d was better than the removal effect of HRT = 5 d. It is evident that the trace quantity organic pollutants of 1,2,4-trichlorobenzene in the source water quality from Meiliang Bay in Taihu Lake can be well degraded by enriched microbes on the artificial media.

The effects of holding temperature and holding time during the spheroidizing annealing on microstructure and mechanical properties of high-carbon chrome steel GCr15 were experimentally studied, especially the ripening process of carbides. The results showed that the spheroidization of carbides was accelerated by optimizing the spheroidizing annealing process. In the case of the same holding temperature, the amount of carbides increases first and then decrease with the increase of holding temperature. The best spheroidizing temperature was about 720°C. Under the conditions of various holding time, the size of carbides and the hardness decrease with the increase of holding time.

Directional solidification process can better control the grain orientation and eliminate the horizontal grain boundary, so excellent performance of alloy can be achieved by it. In the paper, the macro and micro analysis were coupled to predict the microstructure growth of magnesium alloys in directional solidification process. FEM (finite element method) was used to calculate undercooling temperature, by which the macro analysis results were coupled into the micro analysis. Phase-field method (PFM) offers the prospect of carrying out realistic numerical calculation on dendrite growth in metallic systems, and it was employed to calculate real dimension of magnesium alloy microstructure in directional solidification. Different magnitude values of anisotropy that predicted the columnar dendrite evolution were calculated. Quantitative comparison of numerical simulation results to the experiment analysis were carried out. The microstructure obtained by PFM is in good agreement with the actual pattern by the optical microscope observation.

Indium tin oxide (ITO) film is one of the ideal candidates for transparent conductive cathode in methylammonium lead halide perovskite solar cells. Thus, the diffusion of methyl group in ITO film is inevitable, which could deteriorate the optical-electrical property of ITO film. In this study, ITO films with and without (100) preferred orientation were bombarded by the low-energy methyl group beam. After the bombardment, the optical-electrical property of ITO film without (100) preferred orientation deteriorated. The bombardment of methyl group had little influence on the optical-electrical property of ITO film with (100) preferred orientation. Finally, combining the crystallographic texture and chemical bond structure analysis, the diffusion mechanism of low-energy methyl group on ITO lattice and grain boundary, as well as the relation between the optical-electrical property and the diffusion of the methyl group, were discussed systematically. With the above results, ITO film with (100) preferred orientation could be an ideal candidate for transparent conductive cathode in methylammonium lead halide perovskite solar cells.

High strength Bombyx mori silk fibroin (SF) and hydroxyapatite (HA) composite scaffold was obtained by using co-precipitation and salt fractionation method. SEM and mechanical test were used to investigate the structure and properties of the composite scaffolds. The results showed that when the content of NaCl were 10wt%, the scaffolds performed the best mechanical properties (compressive strengths and modulus), which reached 12MPa and 598MPa, respectively. The re sults of SEM suggested that the composites present porous morphologies structure.

A stable N-rich aromatic ligand is employed to prepare energetic zeolite-like metal-organic frameworks. IFMC-1 shows excellent air stability, and the lowest sensitivity toward impact, friction, and electrostatic discharge and the highest predicted heat of detonation among the reported coordination polymers, and even commercial materials (such as trinitrotoluene (TNT)).

Spherical LiFePO4/C precursor powders were successfully prepared by spray pyrolysis. Various types of organic compounds such as glycolic acid, malic acid, citric acid, fructose and sucrose were used as carbon sources. X-ray diffraction analysis revealed that the olivine phase was obtained by calcining over 600 °C under an argon (95%)/hydrogen (5%) atmosphere. The particles exhibited a spherical morphology with approximately 1.5 μm. LiFePO4/C cathode derived from sucrose exhibited higher rechargeable capacity and cycle stability. The rechargeable capacity of LiFePO4/C cathode was approximately 154 mAh/g at 1 C. 90% of initial discharge capacity was maintained after 100 cycles.

Biaxial tension-tension cyclic loading tests were conducted with cruciform shaped specimens using AZ31 Mg alloy sheet, which produced by warm rolling. The residual stress of the sample surface can be obtained by in-situ measurement of x-ray under biaxial low cyclic loading. The surface fracture morphology of the cyclic load test specimens was examined by scan electron microscopy (SEM) and optical microscope. From the results, it was found that the compressive residual stress occurs at crack tip in Y-axis direction. Crack nucleation is earliest in the load ratio r=1. In addition, the crack initiation angle is different due to the coupling effect of KI and KII in mixed modes I and II for 45° case. The crack propagation rate was significantly influenced by the non-singular stress parallel to the crack when it was correlated to the stress intensity range.The surface of the case of 90° is similar to that of the case of 45°, and striation-like-patterns and twin boundaries were observed in the specimens.

The γ-Al2O3 and AgCl/Al2O3 catalyst powders were coated on a stainless steel substrate and influences of preparation methods on coating and NOX reduction were studied. The stainless steel SUS304 was coated by Electrophoretic Deposition Method using dehydrated aluminum nitrate as a binder. The AgCl/Al2O3 catalyst was produced by three kinds of methods, and the difference in the NOX reduction catalyses of coated samples was examined. XRD and SEM were used to study the crystalline structure and cross-section of the coatings. The coatings of γ-Al2O3with the thickness of 3-5 μm and AgCl/Al2O3 catalyst with the thickness of 3-8 μm were made on the surface of SUS304 plate without exfoliation. The NOX conversion of the coated sample with catalyst was about 70 % at the maximum. Furthermore, there was a peak in NOX reduction at the different temperature in the case of the catalyst produced under the conditions A.

A controlled in situ sol–gel synthesis combined with the electrospinning technique and postspun imidization was applied in the fabrication of polyimide/silica hybrid nonwoven nanofiberous fabrics with excellent thermal and mechanical performance. The nanofiberous fabrics were prepared by electrospinning of the solution of tetraethoxysilane (TEOS) and polyamic acid (PAA). The different silica contents in the fabrics were achieved by varying the amount of TEOS while fitting the solid content of PAA. The final polyimide/silica fabrics was obtained after imidization of PAA and gelation of silica phase simultaneously accomplished through a step-wise heating process. Some specific IR techniques and other characterizations indicated the successful incorporation of the silicon dioxide (SiO2) into the PI matrix and the relatively even distribution of the SiO2 in the fabrics. An increase of 133 °C in the decomposition temperature and 4-fold enhancement of the ultimate tensile strength were achieved for the hybrids with a 6.58 wt.% of SiO2 content, compared to the pure PI fabric. The excellent performance could be attributed to the good compatibility between the polyimide and silica, and good adhesion among the fibers, which resulted from the controlled TEOS hydrolysis and the simultaneous imidization and gelation process.

The influence of water cavitation peening (WCP) treatment on the microstructure of pure titanium was investigated. The microstructural evolution in the near-surface of pure titanium as a function of WCP time was characterized by X-ray diffraction (XRD), optical microscopy (OM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). After WCP treatment, changes in the microstructure, as well as residual stress and surface morphologies as functions of WCP time, were recorded using a novel experimental design involving an in situ observation function. The obtained results indicate that twinning plays an important role in the plastic deformation and residual stresses of hexagonal close-packed (HCP) structured metal materials, and therein, that the deformation twinning and twinning interaction were induced by WCP in the strengthening layer. A stable compressive residual stress layer was found in the near-surface of the investigated pure titanium.

γ-Al2O3 coatings were prepared on aluminum-free SUS304 stainless steel by an electrophoretic deposition method. Both TG-DTA and Scanning Electron microscopy are used to study the adhesion property and morphological features of coatings. The results indicate that the thickness of coatings on SUS304 top reaches 3-5 μm without any exfoliation, which is prepared at optimize conditions. Catalytic properties of coated samples for NOx were highly enhanced as compared with the samples prepared by the dip coating method.

A coating process of Ag/Al2O3 catalyst powder on an aluminum-free stainless steel has been investigated for NOx reduction. The stainless steel SUS304 was coated with γ-Al2O3 powder or Ag/Al2O3 catalyst powder by dip coating method using aluminum nitrate as a binder and heated in air. The heating temperature was determined by TG-DTA analysis and the heating period, the concentrations of the binder and the coating powder as well as the number of coats were changed to optimize preparation conditions. As a result, a coating layer with a thickness of approximately 4-5μm was formed on SUS304 without exfoliation. A catalytic ability of the coated sample for NOx reduction was highly enhanced as compared with that coating the catalyst powder without the binder on γ-Al2O3 coating layer.

This research executed the stir quenching that generated the circulation convection of the coolant with a motor pump from the pipe set up in the cooling tank bottom part, and did the quenching experiment of Ag and carbon steel SCM420 that evaluated the cooling power. The oil temperature of the coolant was changed from this experiment research in the condition with constant stir speed of the coolant, and the influence that it exerted on cooling the quenching material was observed. It took the dynamic behavior of the appearance of generation and flaking off of the steam film on the surface of the metal when quenching it with a high-speed camera, and the image was achieved, and moreover, the fixed quantity analysis at the flow velocity of the heat flow was done by using the PIV metrology, and making the convection of the steam film and, the coolant visualization was achieved.

In this research, the gas quenching evaluation device was developed to establish the gas quenching technology, and the PIV system of making to visualization of the thermal flow to clarify the heat transfer behavior in the gas cooling was constructed. And, the cooling curve of the test piece on the surface was measured by the quenching experiments by the gas cooling doing by actually using several kinds of gases, and using the thermo-couple, and the cooling power in the gas cooling process was evaluated.

In the quenching process, heat transfer behavior will is very complex due to boiling, generation of the bubble by the boiling in the quenchant, flaking off of steam film in metal surface. In this research, the behavior of steam film in quenching process was investigated with high-speed video camera by visualization method. The behaviors of the boiling bubbles including generation and movement as well as the breaking during stirring quenching process were clarified. The flow velocity fields around the quenching parts at no stirring and stirring quenching with various flow velocities on nozzle were investigated. In order to identify the heat transfer coefficients by using of the measured cooling curves of surface temperature. Effects of stirring and oil temperature on breaking the steam film were confirmed.

NiCuZn ferrite has been widely applied to multilayer chip inductors in recent years. While fabricating the multilayer structure of ferrite and metal alternatively, it is requested to simultaneously sinter in low temperature for the internal conductor Ag (Melting point 960°C) and ferrite materials. The purpose of this study is to fabricate the NiCuZn ferrite sintered body with high-strength and high-frequency magnetic property. The procedures are as follows: firstly, the NiCuZn ferrite powder was synthesized under a CO2 atmosphere at 500°C from the mixed doxalate which was synthesized by liquid phase deposition method from mixed metal chloride and ammonium oxalate; subsequently, a small amount of boric acid [H3BO3] was added to the powder, and then the NiCuZn ferrite powder compact was formed with Newton press and CIP methods; finally, the NiCuZn ferrite sintered body was fabricated by sintering at 900°C under a CO2 atmosphere. Through the experiments of high temperature shrinkage, evaluation of mechanical strength and magnetic property, NiCuZn ferrite fabricated by this study can present good characters on high frequency and high mechanical strength when the sintering temperature and boric acid additive are 900°C and 0.5 mass%, respectively.

Recently, the ultrafine magnetic particles are applied in many fields, such as magnetic record materials, magnetic fluid, catalysts, biologic medicine materials and so on. In order to fabricate the magnetite nanoparticle with uniform size, liquid phase precipitation method with lower cost is used in this research work. Here, Iron (II) Chloride Tetrahydrate [FeCl2·4H2O], Iron(III) Chloride Hexahydrate [FeCl3·6H2O] mixture solution and NaOH solution were added into the reaction solution by titration method step by step according to the change of pH value, and the solution was being stirred during the reaction process. In this paper, the optimum fabrication condition and the magnetism of composed nanoparticles are investigated. Through evaluation of magnetic property of the fabricated nanoparticle, at room temperature and pH value 7.0, 8nm uniform magnetic particles were synthesized with saturation magnetization value of 48 emu/g and Curie point 471°C.

In the quenching process, heat transfer behavior will is very complex due to boiling, generation of the bubble by the boiling in the quenchant, flaking off of steam film in metal surface. In this research, the behavior of steam film in quenching process was investigated with high-speed video camera by visualization method. The behaviors of the boiling bubbles including generation and movement as well as the breaking during stirring quenching process were clarified. The flow velocity fields around the quenching parts at no stirring and stirring quenching were investigated. In order to identified the heat transfer coefficients by using of the measured cooling curves of surface temperature. Effects of stirring on breaking the steam film were confirmed.

In order to clarify the effect of tear strap in airplane fuselage on crack arrest, experimental research and numerical simulation were carried out in this study. Interaction of multiple axial pre-cracks in a pressurized fuselage was investigated using a small-scale model of an idealized fuselage. The strain between multiple cracks under the situation of rapid crack propagation was measured. The experimental results of a rupturing model fuselage represented the variations of stress intensity factors KI and KII in the mixed mode and the remote stress components σox with crack extension. Deformation at the tips of asymmetrical cracks along the stringer was analyzed by a hybrid method using a finite element analysis program, MDC DYTRAN. The recorded crack velocities were in good agreement with the results of finite element analysis. The crack kinking location, kinking angle and the off-axis crack trajectory were also predicted by numerical analysis and the validity of the calculated results was discussed in comparison with the experimental data.

In order to study metallo-thermo-mechanical behavior during carburized and nitrided quenching, a numerical model when considering quantitative effects of diffused carbon and nitrogen gradients and kinetics of phase transformation is proposed. Coupled calculations of diffusion, phase transformation and stress/strain give the final distributions of carbon and nitrogen contents as well as residual stress and distortion. Within the numerical simulation method, the effects of both transformation and lattice expansion induced from carbon and nitrogen absorption are considered when calculating the evolution of the internal stress and strain. In order to verify the method of numerical simulation, the simulated distributions of carbon and nitrogen content and residual stress/strain of a cylinder during carburized and nitrided quenching are compared with the measured results.