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Semiconductor photocatalysis technology is a promising method to solve the antibiotics pollution in water. Herein, a series of Sn-doped In2.77S4 (Sn-In2.77S4) hybrid photocatalysts for tetracycline degradation have been fabricated via a one-step hydrothermal process. The analytic results exhibit that doping Sn can improve the photocatalytic performance of In2.77S4 nanosheets under the visible light illumination and the doping amount obviously affects the photocatalytic performance of the samples. When the theoretical molar ratio of Sn4+ to In3+ is 0.04:1 (4%), the photocatalytic efficiency of the Sn-In2.77S4 photocatalyst exhibits the highest of 87.4% in comparison with 39.2% of pure In2.77S4 in 20 min. Moreover, its band gap energy has been reduced to 1.56 eV from 1.75 eV and the light absorption range has been broadened. The transfer rate and separation efficiency of photo-generated electron and hole pairs of the samples have also been enhanced. In addition, the holes play a leading role in the photocatalytic degradation process.

The AgBrO3/few-layer g-C3N4 composite photocatalyst has been developed via an in-situ synthetic method. The structure, morphology, light response range, separation and migration efficiency of the photogenerated electron–hole pairs and element valence state of the as-obtained samples have been characterized. The tetracycline was used to discuss the photocatalytic activities of the samples. The photocatalytic degradation mechanism of the as-obtained composites was also researched. The analysis results show that the photocatalytic degradation property of the asobtained composite photocatalyst appears to the tendency of first increasing and then decreasing with increasing the amount of AgBrO3 under visible light illumination. When the mass ratio of AgBrO3 to g-C3N4 is 4:3, in 60 min, the photocatalytic degradation efficiency of the as-obtained composites reaches the maximum of 79%. It is 37% and 45% higher than that of pure AgBrO3 and g-C3N4, respectively. Moreover, the separation and migration efficiency of the photogenerated electron–hole pairs of the as-prepared composites are also enhanced. In addition, superoxide radicals and holes are the dominant active species during the photocatalytic degradation process.

The CdS/ spherical g-C3N4 n-n heterojunction photocatalyst was fabricated via a solvothermal method. The tetracycline was used to characterize the photocatalytic properties of the as-developed hybrids. The photocatalytic degradation mechanism of the as-developed heterojunction photocatalyst was also analyzed. Research results show that CdS nanoparticles are well dispersed in the surface layer of spherical g-C3N4. Moreover, the mass ratio of CdS to spherical g-C3N4 will influence the photocatalytic activity of the asdeveloped composites, which shows the trend of first increasing and then decreasing as it increased. When the mass ratio is 7:1, in 25 min, the as-developed heterojunction shows 93.2 % of the maximum photocatalytic efficiency and still exhibits 83.6 % after 5 times cycle testing. Moreover, the as-developed hybrids can accelerate the electron transport and improve the separation efficiency of photo-generated carriers compared with pure samples. In addition, the holes and superoxide radicals are dominating active species during the photocatalytic degradation process.

The Zn0.5Cd0.5S/SnO2 composite photocatalyst was synthesized via a hydrothermal method. The crystal phase, micromorphology, optical and photoelectric property as well as surface elements valence were characterized using X-ray diffraction, field emission scanning electron microscope, transmission electrical microscope, UV–Vis diffuse reflectance spectrometer, electrochemical impedance spectroscopy and X-ray photoelectron spectroscopy, respectively. Tetracycline was used to discuss the photocatalytic properties of the samples under visible light irradiation. Research results indicate that the as-synthesized Zn0.5Cd0.5S/SnO2 composite photocatalysts show better photocatalytic performance than that of pure samples. Moreover, the photocatalytic activity of the as-synthesized composites presents first increased and then decreased with increasing the amount of SnO2 in the composites. When the quality ratio of SnO2 to Zn0.5Cd0.5S is 7%, in 60 min, the as-synthesized composites reveal the best photocatalytic degradation efficiency of 92.9%, which is high than 85% of Zn0.5Cd0.5S and 0% of SnO2. This is ascribed of the improvement of the separation efficiency of photo-generated electron–hole pairs and the transmission rate of electrons. Furthermore, the decomposition mechanism of as-synthesized composites for tetracycline was also provided. The holes and superoxide radicals play crucial species in the photocatalytic degradation process.

SnO2/AgIO4 hybrids were fabricated by an in-situ synthetic method at room temperature. The structure, morphology, light response range, separation efficiency of the electron-hole pairs and elements of the as-synthesized samples were characterized by adopting X-ray diffraction, scanning electron microscopy, UV-Vis diffuse reflectance spectroscopy, electrochemical impedance spectroscopy and X-ray photoelectron spectroscopy, respectively. The synergistically photocatalytic degradation mechanism of the as-synthesized composites was also proposed. The experimental results reveal that under the visible light irradiation the as-synthesized SnO2/AgIO4 hybrids can enhance the photocatalytic degradation efficiency of rhodamine B compared to pure samples. With increasing the molar ratios of AgIO4 to SnO2, it displays the trend of first increasing and then decreasing. When it is 1:2 in 150 min, the as-prepared hybrids have the highest degradation efficiency of 93.1%, which increases by 6550.0%, 30.5%, and 1505.0% compared to those of pure SnO2, AgIO4, and TiO2 (P25), respectively. Moreover, the Sn-O-Ag cross-linking bonds are formed at the interfaces of SnO2 and AgIO4. In addition, superoxide anion radicals and holes play a major role in the process of photodegradation.

The yolk–shell Bi@void@SnO2 photocatalyst was synthesized via a step-by-step process. The composition, morphology, optical and photoelectrochemical properties as well as the surface chemical composition and states of the samples were characterized by X-ray diffraction, transmission electron microscopy, UV–Vis diffuse reflectance spectra, electrochemical impedance spectra and X-ray photoelectron spectrometer, respectively. The tetracycline has been used to evaluate the photocatalytic activities of the as-synthesized samples. Compared with the degradation efficiency of 16.33% for pure Bi and almost nothing for SnO2 under visible light irradiation, the as-developed Bi@void@SnO2 photocatalyst possesses 81.81% of degradation efficiency. Meanwhile, the light absorption of the as-developed yolk–shell composites is broadened from ultraviolet to visible light comparing to pure SnO2 due to the surface plasmon resonance effect of Bi spheres. Moreover, the superoxide radicals, especially in holes, play leading roles during the photocatalytic degradation process. In addition, the decomposition mechanism of the as-fabricated composites for tetracycline is analyzed in detail.

Zn2SnO4/few-layer boron nitride nanosheets (FBNNS) hybrids were synthesized via a one-step hydrothermal method. The structures, morphology, optical properties, electron transformation and separation of the as-prepared products were characterized by X-ray diffraction, transmission electrical microscopy, UV-vis diffuse reflectance spectroscopy and electrochemical impedance spectroscopy, respectively. Rhodamine B was used to evaluate the photocatalytic activities of the as-prepared samples under visible light illumination. The photocatalytic mechanism was also explored. Experimental results showed that the degradation efficiency of rhodamine B was firstly increased and then decreased with increasing the usage amount of FBNNS. When it was 9 wt% based on the weight of Zn2SnO4, the degradation efficiency of the as-prepared Zn2SnO4/FBNNS-9 wt% composites reached to the maximum of 97.5% in 180 min, which was higher than 39.2 % of pure Zn2SnO4. Moreover, the holes played mainly active roles in photocatalytic reaction process. In addition, the as-prepared hybrids could enhance the separation efficiency of photoexcited carriers compared to pure Zn2SnO4.

The AgI/2D-La2Ti2O7 hybrids were obtained via a facile method at room temperature. Rhodamine B, as an organic dye, was used to determine the photocatalytic activity of the samples. The photocatalytic degradation mechanism was also analyzed. Experimental results display that AgI can broaden the light absorption of La2Ti2O7 under the visible light irradiation. The photocatalytic degradation efficiency of the as-synthesized hybrids appears the tendency of first increasing and then decreasing with increasing the usage of La2Ti2O7. When the usage of La2Ti2O7 is 10%, within 60 min, the as-synthesized hybrids possess the maximum of 93.1%. This is higher than 2.1% of La2Ti2O7 and 80.9% of AgI. Moreover, the improved photocatalytic activity can be attributed to AgI particles conjugating with 2D-La2Ti2O7 nanosheets via chemical-bonds, which can enhance the separation and transformation of the photo-generated holes and electrons. In addition, the dominating role is superoxide radicals during the photocatalytic process.

Full-spectrum-responsive AgI/WS2 composites as an efficient photocatalyst have been synthesised by an in-situ growth of AgI on the surfaces of WS2 nanosheets. The photocatalytic activities of the samples were evaluated by degradation of rhodamine B dilute solution under visible light irradiation. Experimental results showed that the introduction of WS2 nanosheets could enhance light absorption, photocatalytic activity, and recyclability of the pure AgI in the region of visible and infrared light. Moreover, the degradation efficiency of the as-synthesised AgI/WS2 composites exhibited the trend of first increased and then decreased with increasing the amount of WS2 nanosheets. When the usage of WS2 nanosheets was 7 wt%, the as-prepared composites possessed the maximum of 91.2% in 30 min. Furthermore, after three cycles of degradation, it could still degrade 89.0% of rhodamine B, obviously higher than 11.4% of pure AgI. In addition, a possible degradation mechanism of the as-synthesised AgI/WS2 hybrids was provided.

The Ag2CrO4/SnO2 n–n type heterojunction has been fabricated by coupling Ag2CrO4 particles with SnO2 nanorods via an in situ synthetic method. The photocatalytic degradation mechanism of the as-prepared heterojunction has also been discussed. Characterization results revealed that the as-fabricated Ag2CrO4/SnO2 composites could reinforce the photo-degradation competencies for rhodamine B dilute solution compared to pure Ag2CrO4 and SnO2 samples. As the increase in the molar ratios of Ag2CrO4–SnO2, the photocatalytic degradation efficiency appeared to the tendency of first increasing and then decreasing. When it was 4:10, in 90 min, the as-obtained samples possessed the vintage photocatalytic degradation efficiency of 95.8% among of pure SnO2, Ag2CrO4 and the as-prepared composites with various molar ratios, respectively. Furthermore, the Ag2CrO4 and SnO2 were connected via chemical bonds to form the homogenous heterojunction. It could boost the separation and transfer of the photogenerated holes and electrons. In addition, the holes, hydroxyl and superoxide radicals played a major role during the photodegradation process.

A novel AgCl/AgIO4 composite was fabricated via an in-suit synthetic method. The as-prepared samples have been characterised by using X-ray diffraction, transmission electron microscopy, scanning electron microscopy, UV–vis diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy and electrochemical impedance spectroscopy. Rhodamine B dilute solution was used to discuss the photocatalytic activities of the as-prepared composites under the visible light irradiation. Experimental results showed that with increasing the contents of AgIO4 the photocatalytic activity of the as-prepared hybrids was first increased and then decreased. When the molar ratio of AgCl to AgIO4 was 1:5, in 30 min, the as-prepared composites with the bandgap of 1.21 eV exhibited the highest photocatalytic activity and possessed 96.3% of degradation efficiency. That was increased by 71.5 and 27.9% compared with AgCl and AgIO4, respectively. Moreover, AgCl was linked with AgIO4 via chemical bonds rather than physical contact at the interfaces of these two semiconductors. In addition, a possible photocatalytic degradation mechanism for the as-prepared hybrids was also presented.

Diamond is the hardest natural material, but its practical strength is low and its elastic deformability extremely limited. While recent experiments have demonstrated that diamond nanoneedles can sustain exceptionally large elastic tensile strains with high tensile strengths, the size- and orientation-dependence of these properties remains unknown. Here we report maximum achievable tensile strain and strength of diamond nanoneedles with various diameters, oriented in , and -directions, using in situ transmission electron microscopy. We show that reversible elastic deformation depends both on nanoneedle diameter and orientation. -oriented nanoneedles with a diameter of 60 nm exhibit highest elastic tensile strain (13.4%) and tensile strength (125 GPa). These values are comparable with the theoretical elasticity and Griffith strength limits of diamond, respectively. Our experimental data, together with first principles simulations, indicate that maximum achievable elastic strain and strength are primarily determined by surface conditions of the nanoneedles., While diamond is the strongest natural material, it fails to reach its theoretical elasticity limits and is brittle. Here, the authors show that thin -orientated diamond nanoneedles can reach diamond’s theoretical strength and elasticity limits in tension.

The direct Z-scheme Ag2WO4/WS2 photocatalysts had been fabricated by using a deposition method. Experimental results indicated that WS2 nanosheets could improve the photocatalytic activity, light absorption and recyclability of Ag2WO4 under the visible light irradiation. The degradation efficiency of the as-obtained Ag2WO4/WS2 hybrids for rhodamine B displayed first increasing and then decreasing with increasing the usage of WS2 nanosheets. When the usage of WS2 was 15 wt%, in 120 min, it reached the maximum of 97.8%, which was higher than 17.8% of pure Ag2WO4. Moreover, after three cycles of the degradation, the as-prepared hybrids still possessed 94.4% of the degradation efficiency, which increased by 1211.1% compared with pure Ag2WO4. Moreover, superoxide and hydroxyl radicals played major role during the process of photocatalytic degradation. The enhanced photocatalytic activity could be ascribed to the formation of direct Z-scheme photocatalytic system between Ag2WO4 and WS2.

The nanosized Bi-doped SnO2/reduced graphene oxide 3D hybrids have been synthesized via one-step hydrothermal method. The structures, morphologies, photocatalytic activities of the as-prepared samples were discussed, respectively. The formation mechanism of the as-prepared hybrids was also proposed. Experimental results indicated that the usage amount of Bi2Sn2O7 obviously affected the photocatalytic performance of the as-prepared products. When it was 450 mg, the as-prepared sample possessed the band gap energy of 1.9 eV and the photocatalytic efficiency of 90% in 210 min for degradation of rhodamine B solution. In addition, triethylene tetramine and the as-prepared carbon hydrogel could act as reductant to synergistically reduce Bi2Sn2O7 into Bi-doped SnO2 particles during the formation of the hybrids.

Visible and near-infrared light responsed Sn1−x Bi x S2nanosheets was synthesised via a simple hydrothermal method. Rhodamine B was adopted to evaluate the degradation efficiency of the as-prepared samples. Experimental results showed that the doping content of Bi3+ could obviously affect the degradation efficiency of SnS2. It was first increased and then decreased with increasing the Bi3+ content under the visible light irradiation. When the mole fraction of doping Bi3+ was 5%, the as-prepared Sn0.95Bi0.05S2 with a bandgap of 0.38 eV had the highest degradation efficiency of 95.9% in 120 min. Moreover, the as-prepared composites possessed more effective electron–hole pair separation than that of pure SnS2. In addition, a possible degradation mechanism of the as-prepared Sn0.95Bi0.05S2 was proposed.

Novel p-n heterojunction of Bi2Sn2O7-Ag2CrO4 photocatalysts with various contents of Bi2Sn2O7 were in-situ synthesized at 25 °C. X-ray diffraction, transmission electron microscopy, UV–vis diffuse reflectance spectra, photoluminescence emission and electrochemical impedance spectra were employed to characterize the as-prepared samples. Experimental results showed that, under the visible light irradiation, with increasing the amount of Bi2Sn2O7, the degradation efficiency of the as-prepared hybrids was first increased and then decreased. It possessed the highest degradation efficiency of 97.5 % for rhodamine B in 120 min, which was obviously higher than that of 76.7 % of Ag2CrO4 and 11.8 % of Bi2Sn2O7, respectively. Moreover, it possessed the degradation efficiency of 90.4 % for methyl orange and 99.8 % for methylene blue. In addition, after it was circulated for 5 times, the as-prepared hybrids still possessed the degradation efficiency of 90.2 % for rhodamine B, which increased by 240.4 and 1950.0 % in comparison with Ag2CrO4 and Bi2Sn2O7, respectively. The enhanced photocatalytic activity could be attributed to the formation of the p-n heterojunction at the interface of p-Bi2Sn2O7 and n-Ag2CrO4.

Hexagonal boron nitride was adopted as a heterogeneous nucleation agent to fabricate polyamide 6 based nanocomposite films via a solution casting method. Isothermal crystallization behaviors of the...

Most super-resolution microscopy methods can only be applied to incoherent imaging processes such as fluorescence imaging, but coherent image processing resolution still needs improvement. In this paper, confocal microscopy with structured detection is presented in a coherent imaging process to achieve a higher resolution with a comparably large pinhole. The approximate coherent image formation, coherent transfer function, and reconstruction process are discussed. Simulation results indicate that the width of the coherent transfer function expands in the x and y directions. The experimental results show that the resolution excels with a confocal microscope having a same-sized detector, and can be 1.7 times as large as that of a coherent wide-field microscope.

In this study, 5, 10, and 15 bi-layers of poly(diallyl dimethyl ammonium chloride) (PDAC)/sulfonated-poly(2,6-dimethyl 1,4-phenylene oxide) (sPPO) containing Pt55-Ru45 catalyst are self-assembled on both sides of the proton exchange membrane (PEM) (i.e. Nafion-117) using a layer-by-layer technique to serve as the membrane electrode assembly (MEA) for a direct methanol fuel cell (DMFC). Experimental results show that the XC-72 carbon particles with Pt55-Ru45 alloy catalyst in the sPPO layer penetrated the PDAC layers forming a continuous catalyst layer throughout the self-assembly PDAC/sPPO bi-layers. This continuous catalyst layer structure provides a conductive media and transfer channel for the produced electrons and protons in the catalyst layer to the external circuit and the PEM and cathode sides. Our self-assembly MEAs have higher mass catalyst activity than the MEA prepared by the conventional method under CH3OH/O2 fuel cell testing, i.e., 1588.8 (5 bi-layers), 1205.8 (10 bi-layers), and 350.0 A g−1 Pt-Ru (15 bi-layers) vs. 80.0 A g−1 Pt-Ru (for conventional MEA), respectively. The 10 bi-layers of PDAC/sPPO sample loaded with 0.017 mg Pt-Ru cm−2 catalyst had the highest power density of 3.70 mW cm−2 (@0.18 V) and 74.1 mW cm−2 (@0.40 V) under the CH3OH/O2 and H2/O2 fuel cell operating at 80 °C, respectively.

The Zn2+ doped In2.77S4 (Zn–In2.77S4) photocatalyst has been synthesized via a one-step hydrothermal method. The tetracycline was adopted to measure the photocatalytic performance of the as-fabricated Zn–In2.77S4 composites. The probable photocatalytic degradation mechanism of the as-prepared composites was also discussed. Experimental results reveal that doping Zn2+ into In2.77S4 can broaden the light absorption range and improve the recycle ability as well as the separation efficiency of photo-generated electron–hole pairs of pure In2.77S4. Moreover, as the doping amount of Zn2+ increased the photocatalytic efficiency of the as-obtained Zn–In2.77S4 composites appears the tendency of firstly increasing and then decreasing. When the molar ratio of Zn2+ to In3+ is 0.04:1 (4%), in 15 min, the photocatalytic efficiency of the as-developed Zn–In2.77S4 photocatalyst reaches to the maximum of 90.0%. It is higher than 31.8% of pure In2.77S4. Furthermore, superoxide radicals and holes play major roles in the process of photodegradation tetracycline. This research can supply a promising guide to solve antibiotics pollution in water under sunlight.

The In2.77S4/SrCO3 heterojunction photocatalyst had been prepared by one-step hydrothermal method. X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectrometry, UV–Vis diffuse reflectance spectroscopy and electrochemical impedance spectroscopy were used to analyze the structure, morphology, chemical compositions, optical properties and charge carrier behaviors of the as-prepared In2.77S4/SrCO3 hybrids, respectively. Experimental results revealed the SrCO3 could obviously improve the recyclability and photocatalytic activities of In2.77S4 nanosheets for both methyl orange and tetracycline oxidation under visible light. The photocatalytic degradation efficiency of the as-obtained In2.77S4/SrCO3 hybrids was first increased and then decreased with increasing the molar ratio of Sr(NO3)2 to In(NO3)3·4.5H2O. When it was 0.4:1, that of the as-prepared hybrids with the band gap of 1.63 eV reached the maximum of 96.0% in 30 min for methyl orange and 82.7% in 20 min for tetracycline. These were higher than 88.0% and 40.0% of In2.77S4 nanosheets as well as 0.8 and 1.8% of SrCO3 particles, respectively. After three cycles, its photocatalytic efficiency still possessed 92.7% for methyl orange and 80.3% for tetracycline, which were much higher than 35.3% and 11.3% of In2.77S4 nanosheets. Moreover, the possible photocatalytic degradation mechanism of the In2.77S4/SrCO3 hybrids was also proposed.

SnS2/few layer boron nitride nanosheets composites were synthesized via a one-step hydrothermal method. The as-prepared samples were characterized by X-ray diffraction, transmission electrical microscopy, UV–vis diffuse reflectance spectroscopy, Fourier transform infrared spectroscopy, photoluminescence emission spectra and electrochemical impedance spectroscopy, respectively. Rhodamine B was adopted to evaluate the degradation efficiency of the as-prepared samples under visible light irradiation. Experimental results showed that, compared to pure SnS2, the few layer boron nitride nanosheets could improve photocatalytic activities of the samples for the degradation of Rhodamine B. With increasing the usage amount of the few layer boron nitride nanosheets, the degradation efficiency was first increased and then decreased. When the usage amount of the few layer boron nitride nanosheets was 10 wt%, it exhibited the highest degradation efficiency of 93.7% in 210 min, which was higher than 50% of pure SnS2. After it was recycled for four times, it still possessed 88.7% of degradation efficiency. This was increased by 1008.7% than pure SnS2. Moreover, it had band gap energy of 1.78 eV, obviously smaller than 2.06 eV of pure SnS2. In addition, a possible photocatalytic mechanism was also presented.

To explore how the degree of cathode oxidation influences the ignites characteristics of ring He-Ne laser,photoelectric retarding potential method is used to investigate the variation of the work function with the cathode oxidation.As the cold cathode of discharge device,aluminum′s work function and the work function variation before and after oxidation are measured under the high vacuum conditions by Лукирский spherical photo electronic measure equipment and parallel electrodes optic-electronic discharge device.The experimental results show that work function of aluminum cathode in the natural oxidation is 2.60±0.2 eV.The mass percent of oxygen on aluminum cathode surface is 3.2%.At different times of oxidation process,the work function of aluminum cathode decreases with the growth of the oxidation time.The reasons that work function measurements of aluminum cathode may be in 2.5～4.3 eV are explained.The conclusion from the experimental results is the oxidation time is longer,the smaller the work function of the material,the more conducive to the ignition of the ring He-Ne laser within a certain range.Cathode oxidation also affect the ignition voltage and the cathode potential drop of gas discharge process.So the choice of the optimal oxidation time ought to consider these two factors.

The influence of the surface polarization, Ps , on a nematic liquid crystal (NLC) cell is investigated analytically. Flexoelectric polarization is considered, but selective ion absorption is ignored. The differential equations are derived for tilt angle, θ, of director n and the corresponding boundary conditions based on Gibbs free energy, and their solutions discussed. Equations for the reduced threshold voltage, uth , and the reduced saturation voltage, usat , are deduced and the relationships between uth , usat and reduced strength of surface polarization, p, derived.

A new method is proposed in this paper to improve transverse resolution of a confocal microscope. By setting up the model of a confocal microscope system through spatiotemporal modulation with moving gratings or acousto-optical modulation without defocus distance under coherent light illumination and deducing two-dimensional coherent image formula and transfer function, simulation tests are run with or without spatiotemporal modulation to prove the effectiveness of the proposed method. Simulation results indicate the proposed method can be used to improve the transverse resolution of a confocal microscope system.

On the basis of the modified general Rapini–Papoular expression for the anchoring energy, a twisted nematic liquid crystal cell has been studied analytically. In this paper, a new variable is introduced and is suitable for the calculation of the threshold point and the saturation point. The free energy being smallest in the equilibrium state, we find that bistable states can be formed from the uniform twisted state plus the disturbed state, the disturbed state plus the saturation state, and the uniform twisted state plus the saturation state.

Titanium and its alloys find wide applicability in aerospace and medicine. The key restricting factor in using the Ti-based alloys is the difficulties associated with the processing of the alloy as they are forged at temperatures >800 °C. In the current work, Ti was mechanically alloyed in a tumbler mixer with Al, Fe and Zr with a charge to ball ratio of 1:2. The mechanical properties such as tensile and compression strengths and the hardness profile were evaluated as per the ASTM/MPIF standards. SEM analysis of the fracture surfaces indicated that samples sintered in vacuum exhibited brittle failure while those sintered in argon exhibited ductile–brittle failure. The tensile strengths ranged from 300 to 850 MPa for the samples tested. The alloying time affects the fracture mode and the strength of the alloy. Strain in excess of 20% was obtainable during upsetting samples alloyed for 48 h which is comparable to the conventional Ti–6Al–4V alloy.

On the basis of the modified Rapini-Papoular expression for the anchoring energy, the properties of the transition at saturation point for weak anchoring NLC cells has been studied analytically. We find that this transition may be of second order, as is usually predicted by many authors; however, it may also be first order. Whether it is first or second order is determined by the material, anchoring energy and thickness of the cell. The conditions for first order transition are deduced by an analytical method, and the results of calculation are shown by graph for κ (= K 11 / K 33 ) values 0.8, 0.6 and 0.4. The saturation field strengths for the first order transition case are calculated and shown in the table.

We demonstrate a low threshold polymer solid state thin-film distributed feedback (DFB) laser on an InP substrate with the DFB structure. The used gain medium is conjugated polymer poly[2-methoxy-5-(2-ethylhexyloxy)-1, 4-phenylenevinylene] (MEH-PPV) doped polystyrene (PS) and formed by drop-coating method. The second order Bragg scattering region on the InP substrate gave rise to strong feedback, thus a lasing emission at 638.9 nm with a line width of 1.2 nm is realized when pumped by a 532nm frequency-doubled Nd:YAG pulsed laser. The devices show a laser threshold as low as 7 nJ/pulse.

It is well known that potassium ion channels have higher permeability than K ions, and the permeable rate of a single K ion channel is about 108 ions per second. We develop a hierarchical model of potassium ion channel permeation involving ab initio quantum calculations and Brownian dynamics simulations, which can consistently explain a range of channel dynamics. The results show that the average velocity of K ions, the mean permeable time of K ions and the permeable rate of single channel are about 0.92 nm/ns, 4.35 ns and 2.30×108 ions/s, respectively.

In this paper, the effect of temperature on the composition and structure of the Si3N4 thin film is investigated. X-ray diffraction pattern and transmission electron microscope (TEM) analyses show that the Si3N4 film undergoes the transition from amorphous to crystalline phase with increasing deposition temperature. Infra-red qualitative analysis shows that the content of hydrogen decreases with increasing deposition temperature. The stoichiometric of Si3N4 is investigated by x-ray photoelectron spectroscopy or electron spectroscopy for chemical analysis.

Concrete-filled steel tubes (CFST) and composite steel plate shear walls (CSPSW) have advantages of high bearing capacities, high stiffness, excellent energy dissipation ability, and so on. Concrete-filled steel tube can be used as a column in composite frames. If composite steel shear walls are installed in composite frames, a new kind of composite structure is composed. As shear walls are not connected to frame columns, the premature overall buckling or local buckling failure of columns can be prevented. Meanwhile, the structural stiffness and bearing capacity can be adjusted by changing the size or the number of shear walls, which is attractive to both structural design engineers and architects. This paper presents the behavior of composite frame infilled composite steel plate shear walls connected with frame beams. A 20-storey composite structure model is developed using the finite element software OpenSees. Both the nonlinear static and dynamic response are analyzed to investigate the behavior of composite structures.

The electronic and thermoelectric properties of Mg2Si under hydrostatic pressures have been investigated using the first principles calculations with general potential linearized augmented plane-wave method and the semiclassical Boltzmann theory with the rigid band approach and the constant scattering time relaxation approximation. In this work, the hydrostatic pressure is simulated by applying equiaxial strain method for the cubic anti-fluorite structure of Mg2Si in space group Fm3m. The strain values ranging from -0.03 to 0.03 describe the compressive and tensile Processes under pressure. The band structure, electrical conductivity, Seebeck coefficient and power factor have been calculated and analyzed in detail.#br#From the band structure in Mg2Si one can see that the bottom of the conduction band shows significant changes under strains. Especially, when the strain is up to 0.02, there are two twofold-degeneracy states occurring at the center of the Brillouin zone. The top of the valence band shows a slight change due to the strain effect. For the unstrained structure, our calculated thermoelectric data are in accordance with other reports. Moreover, the results indicate that when the value of strain is up to 0.02, the transport properties get an optimal functioning of Mg2Si due to electron doping. At 300 K, the Seebeck coefficient improves obviously and comes up to 126%. And the power factor is up to 47% (45%) at T=300 K (700 K). Consequently, the thermoelectric properties can be improved through applying negative pressures to the Mg2Si crystal. For the case of hole doping, the transport parameters change obviously at a small strain value, and change gently at a high strain values. When the strain is up to 0.01, the Seebeck coefficient reaches the maximum value 439 μV/K-1. But, the power factor only increases 0.9%–2%. Hence, we can conclude that the hydrostatic pressures have a slight influence on the thermoelectric properties of hole-doped materials.