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A dual phase structure consisting of ferrite and martensite has been achieved in Ti-bearing steels microalloyed with Mo or Cu, respectively, which were treated under different austenitizing and hot deformation conditions to investigate the effects of second microalloying elements and thermomechanical processes on the microstructural evolution and mechanical properties. The results showed the largest microhardness values, 343 HV0.1 for Ti–Mo steel and 307 HV0.1 for Ti–Cu steel, in microalloyed steels austenitized at 1200 °C with 30% deformation strain. Furthermore, critical patent analysis revealed that higher tensile strength is achieved in a Ti–Mo steel having a larger Ti/Mo atomic ratio, but no such relationship between tensile strength and Ti/Cu atomic ratio applies to Ti–Cu steel. This finding can be ascribed to the different metallurgical effects of Mo and Cu in the Ti-bearing steels. For example, the addition of Mo in a Ti-bearing steel leads to tiny carbides due to the decrease in coarsening via the synergistic effect of Ti and Mo. On the other hand, the separate precipitation of TiC and Cu in the Ti-bearing steels is consistent with the results of patent analysis. That is, the tensile strength of these steels is not associated with the Ti/Cu atomic ratio.

The solid state incandescent light emission device (SSI-LED), which can emit the broadband warm white light, is made from the high-k MOS capacitor after the dielectric breakdown [1-4]. Electrical properties of the capacitor, such as interface defect density (Dit ), oxide trapped charge density (Qot ), equivalent oxide thickness (EOT), and leakage current density (Jleakage ) are important to the dielectric breakdown process and eventually the optical properties of the emitted light. Since the zirconium hafnium oxide (ZrHfO) high-k material has superb gate dielectric properties, e.g., high crystallization temperature, low interface state density, oxide trapped charges, and high effective k value, it has been used as the gate dielectric layer of the MOS capacitor [5,6]. On the other hand, the WOx dielectric-based MOS capacitor and SSI-LED has been studied. The latter emitted light with relative high intensity due to the high emissivity coefficient of the W component [7]. However, the capacitor has a high leakage current which can be a reliability concern. In this paper, three types of MOS capacitors, i.e., with gate dielectrics made of ZrHfO, WOx, and ZrHfO/WOx/ZrHfO/WOx/ ZrHfO/WOx/ZrHfO, separately, have been fabricated into SSI-LEDs and studied for electrical and optical properties. MOS capacitors were prepared on a DHF pre-cleaned p-type silicon (1015 cm-3) wafer. For the ZrHfO capacitor, the gate dielectric layer was sputter-deposited from the Zr/Hf (12/88 wt%) target in Ar/O2 (100:100 sccm) at 5 mTorr and 60 W for 12 min. The WOx layer was sputter-deposited from the W target (99.999 %) in Ar/O2 (40:100 sccm) at 5 mTorr and 60 W for 12 min. For the WOx embedded capacitor, the ZrHfO (2 min)/WOx (2 min)/ZrHfO (2 min)/WOx (2 min)/ ZrHfO (2 min)/WOx (2 min)/ZrHfO (2 min) stack was deposited in one pump down under the same conditions as each individual layer. The post-deposition annealing (PDA) was conducted at 900 ̊C under the O2 atmosphere for 5 min in furnace. An 80 nm thick ITO was sputter deposited and wet etched into round gate electrodes using an aqua regia solution. Then, the backside of the wafer was deposited with an aluminum thin film and annealed at 400 ̊C under H2/N2 (10/90) for 5 min. The dielectric breakdown voltage of the capacitor was determined from the current density-gate voltage (J-V) curve. The light emission characteristics the SSI-LED were measured from an optical emission spectrometer (OES, StellarNet). Electrical characteristics of the capacitors before and after the dielectric breakdown were discussed with respect to the gate dielectric material properties. Figure 1 shows the emission spectra of the 3 SSI-LEDs. They all emit broad band light in the range of UV to near IR. They are similar to the visible wavelength region of the solar light. The peak lengths λpeak’s of the ZrHfO, WOx, and WOx embedded devices are 638 nm, 687.15 nm, and 663 nm, respectively. The WOx SSI-LED has the highest emission intensity. It was reported that the emissivities of the pure (99.99 %) tungsten and the hafnium-3 wt% zirconium materials were 0.434 [8] and 0.30 [9] at 2000 K, respectively. Therefore, the inclusion of W component in conductive path may increase the light emission intensity of SSI-LED. According to the emission spectra, the CIE chromaticity chart has been prepared. The color correlation temperatures (CCT’s) and color rendering indices (CRI’s) were calculated. Y. Kuo, ECS Trans., 69, 23-29 (2015). C.-C. Lin and Y. Kuo, ECS J. Solid State Sci. Technol., 3, Q182 (2014). C.-C. Lin and Y. Kuo, J. Vac. Sci. Technol. B, 32, 011208 (2014). Y. Kuo and C.-C. Lin, Appl. Phys. Lett., 102, 031117 (2013). T.-C. Chang, F.-Y. Jian, S.-C. Chen and Y.-T. Tsai, Materials today, 14, 608-615 (2011). G. E. Moore, Cramming more components onto integrated circuits, McGraw-Hill New York, NY, USA (1965). M. Lorenz, H. von Wenckstern and M. Grundmann, Adv. Mater., 23, 5383-5386 (2011). R. D. Larrabee, JOSA, 49, 619-625 (1959). P.-F. Paradis, T. Ishikawa and S. Yoda, Int. J. Thermophys., 24, 239-258 (2003). Figure 1

Chiral self‐sorting is intricately connected to the complicated chiral processes observed in nature and no artificial systems of comparably complexity have been generated by chemists. However, only a few examples of purely organic molecules have been reported so far, where the self‐sorting process could be controlled. Herein, we describe the chiral self‐sorting of large cubic [8+12] salicylimine cage compounds based on a chiral TBTQ precursor. Out of 23 possible cage isomers only the enantiopure and a meso cage were observed to be formed, which have been unambiguously characterized by single crystal X‐ray diffraction. Furthermore, by careful choice of solvent the formation of meso cage could be controlled. With internal diameters of d in=3.3–3.5 nm these cages are among the largest organic cage compounds characterized and show very high specific surface areas up to approx. 1500 m2 g−1 after desolvation., Highly selective chiral self‐sorting. The chiral self‐sorting behavior of large cubic [8+12] salicylimine cage compounds was investigated, revealing a high selectivity for the most symmetric cage compounds, for which an explanation is presented. The properties of the isolated enantiopure and meso cage compounds were investigated by single crystal X‐ray diffraction and gas sorption measurements showing high porosities and selectivities.

Charge transfer (CT) crystals of an electron donor and an acceptor have electronic properties that are different from the two pure components. Despite the great potential of such CT crystals have f...

One-pot synthesis of novel hydrogel-based anion exchange membranes (AEMs), with only a single-phase monomer mixture, was used to eliminate surface heterogeneity and generate reproducible electroconvective microvortices in the over-limiting region of the current-voltage characteristic (CVC) curves. Diallyldimethylammonium chloride (DDA) was used as the main component to provide the cation charge groups, and 2-hydroxyethyl methacrylate (HEMA) and ethylene glycol dimethyl acrylate (EGDMA) were used as the auxiliary structure monomers. The uniform membrane structure allowed reproducible and sensitive DNA detection and quantification, as probe-target surface complexes can gate the ion flux and produce large voltage shifts in the over-limiting region. Suppressed membrane curvature due to controlled swelling is a crucial part to avoid the reduction of depletion region for maintaining the influence of target gene hybridization. Fourier-transform infrared (FTIR) spectroscopy verified the synthesized membrane structure, with a residual vinyl group that allows easy carboxylation via additional photografting reaction. Consequently, a significantly higher DNA probe functionalization efficiency is obtained on the homogeneous AEMs, evidenced by the increasing nitrogen element content and bonding via X-ray photoelectron spectroscopy (XPS). The DDA content was optimized to provide a sufficient coulomb force between AEM and nucleic acid backbone to promote the specific binding efficiency but without high dimensional swelling which might change the surface geometry and restrict the voltage shifting for sensing in the over-limiting region, and the optimal DDA/HEMA ratio was found to be 4/10. The synthesized AEM sensor for recombinant 35S promoter sequence identification exhibited a reproducible calibration standard curve with dynamic range between 30 fM and 1 μM and high selectivity with only 0.01 V shift for 1 μM nontarget oligo.

The hafnium oxide based high-k dielectric material has been used to replace SiO2 in advanced MOSFETs to lower down the leakage current based on the same equivalent oxide thickness (EOT) of SiO2 [1,2]. The Zr-doped HfO2 (ZrHfO) thin film has many advantages over the undoped HfO2 thin film with respect to the higher permittivity, higher crystallization temperature, lower interface thickness, and lower interface density of states [3-6]. MOS capacitors with EOT less than 1 nm has been successfully prepared using the sputter deposited ZrHfO [5]. The metal electrode material is crucial to the device performance because it could diffuse into the structure to introduce dipoles or new charge trapping sites [7,8]. In this paper, electrical properties of MOS capacitors made of two different gate electrode materials, i.e., copper (Cu) and molybdenum (Mo), were investigated. MOS capacitors were fabricated on p-type Si (100) 1015 cm-3 wafers. The ZrHfO film was sputtered deposited from a Zr/Hf (12/88 wt. %) target under Ar/O2 (1:1 sccm) at 10 mTorr and 80 W for 12 min. The sample was subsequently annealed at 800°C in N2 for 5 min. Then, a 200 nm thick Cu or Mo electrode film was sputter deposited at 10 mTorr and 80 W, i.e., 20 min for the former and 120 min for the latter. They were etched into round gate electrodes of 200 µm, 300 µm and 400 µm diameters. The Mo electrode was wet etched with a H3PO4/HNO3/CH3COOH/H2O (80:5:5:10) solution. The Cu electrode was etched with a plasma-based etch process of which the detailed process condition can be found in refs [9]. Then, the sample was treated with a post metal annealing (PMA) step at 250°C in N2 for 10 min. Samples without the PMA treatment, i.e., controlled samples, were also prepared and measured for comparison. Electrical properties, e.g., EOT, VFB , Dit , and Qot , of the sample were extracted from the C-V curve using the method described in ref 10. Figure 1 shows the C-V hysteresis curves of Mo gated capacitors (a) before and (b) after PMA. The samples were measured with the gate voltage (Vg ) swept from -3 V to 3 V (forward) and then back to -3 V (backward). The control sample shows a large flat-band voltage shift ( ) of 1.4881 V while the annealed sample shows a much smaller ’s of 0.083 V. Also, the Qot is decreased from 9.611011 to 1.091011 cm-2 for the control and annealed samples [10]. The long Mo sputtering time may induce hole-trapping defects in the high-k film or at the high-k/Si interface. In addition, it was reported that the Mo gate could react with high-k film to form new bonds that reduced the work function [11]. The 250˚C annealing step can effectively reduce defects in various parts of the capacitor. Figure 2 shows the C-V hysteresis curves of Cu gated capacitors (a) before and (b) after PMA. Before PMA, the C-V curve is similar to that of a good capacitor with a low of 0.012 V, which corresponds to a low charge trapping density [10]. However, after PMA, the C-V curve distorted. It shows the strong inversion phenomenon, which indicates the possible high electron concentration at the interface exceeding the dopant concentration near the wafer interface [12]. Since Cu can easily diffuse through a dielectric film [13], it is possible that Cu diffuses through the high-k gate dielectric during the PMA step. Cu in the high-k film may exist in the CuOx form, which changed the charge trapping states and locations. More discussions on the above mechanism will be presented. Lingguang Liu acknowledges the financial support of National Natural Science Foundation of China (Grant Number:61771382), China Scholarship Council (No. 201806280283) and the Shaanxi International Science and Technology Cooperation and Exchange Program (2018KW-034). 1. Kang, et al., IEEE EDL, 21, 181 (2000). 2. I. Hegde, et al., JAP, 101, 074113 (2007). 3. Kuo, ECST, 3, 253 (2006). 4. Kuo, et al., ECST, 1, 447 (2006). 5. Yanet al., ECS SSL, 10, H199 (2007). 6. Luo, et al., APL, 89,072901 (2006). 7. Ravindran, et al., APL, 89, 263511 (2006). 8. C. Vezzoli, et al., Ceram. Int., 23, 105 (1997). 9. Kuo and S. Lee,APL, 78, 1002 (2001). 10. H. Nicollian and J. R. Brews, MOS Physics and Technology, p424, Wiley, New York (1982). 11. Ha, et al., JJAP, 42, 1979-1982 (2003). 12. Ytterdal, et al., Device Modeling for Analog and RF CMOS Circuit Design, p4, Wiley (2003). 13. D. McBrayer, et al.,JES, 133, 6,1242 (1986). Figure 1

First-principles calculations have been conducted to gain insight into the vacancy trapping mechanism of H atoms produced by neutron induced transmutation in Be12Ti, which is a promising candidate for the plasma facing materials in fusion reactors. The microscopic mechanisms for H trapping by four kinds of vacancies, namely, Be1, Be2, Be3, and Ti vacancy have been studied by calculating the solution energies and the trapping energies of hydrogen-vacancy complexes. We have included a zero-point energy correction that generally leads to a higher trapping energy, but the energy tendency remains unchanged. Vacancies serve as trapping centers to induce H atoms to segregate on their internal surface by providing an optimal H-embedding isosurface of charge density. The Ti vacancies exhibit a stronger H trapping ability than the Be vacancies. A Ti vacancy can capture up to ten H atoms, while the maximal number of H atoms that a Be vacancy can accommodate is four. But a Be1 vacancy can only capture two H atoms if the zero-point energy correction is included in the simulation. Among all HnVBe1 (n = 1–5) complexes, the configuration of H2 VBe1 has the lowest H solution energy. The H2 molecules are not formed in the most stable hydrogen-vacancy complexes explored. The present results provide a fundamental image of vacancy trapping mechanism for H atoms as well as H bubble formation in solid Be12Ti, which is extremely important for the reduction of radioactive tritium inventory within fusion reactor and appropriate handling of radioactive nuclear wastes during the decommissioning of the fusion blanket.

Transition metal-doped Sb2Se3 has become a heated topic caused by the strong nonlinear optical response and the ultrafast response time at high laser excitation. In this paper, the Co-doped Sb2Se3 with different doping amount (0.5, 1.0, and 1.5 W) nanofilms were prepared by magnetron sputtering technology, and the nonlinear behavior of Co-doped Sb2Se3 nanofilms at near infrared were systematically studied. The results of the femtosecond Z-Scan experiment indicate that the Co-doped Sb2Se3 nanofilms exhibit broadband nonlinear response properties owing to the free carrier absorption, the Kerr refraction, the two-photon absorption, and the free carrier refraction. The nonlinear absorption coefficients of Co-doped Sb2Se3 nanofilms are from 3.0 × 10−9 to 2.03 × 10−8 m/ W under excitation at 800, 980, and 1,030 nm, and the nonlinear refractive index of the Co-doped Sb2Se3 nanofilms is from 4.0 × 10−16 to -3.89 × 10−15 m2/ W at 800, 980, and 1,030 nm. More importantly, Co-doped Sb2Se3 (1.5 W) nanofilm exhibits ultrafast carrier absorption ( 6.3. The Co-doping content can controllably tune the crystalline degree, the ultrafast carrier absorption, the intensity of the reverse saturation absorption, the broadband nonlinear optical response, and the carrier relaxation time of Co-doped Sb2Se3 nanofilms. These results are sufficient to support their applications in broadband nonlinear photonic devices.

Graphene/MoS2/Ag thin films were successfully prepared by the magnetron sputtering technique and liquid phase exfoliation. Structure, morphology, optical properties, and nonlinear optical characteristics of the graphene/MoS2/Ag and graphene/MoS2 thin films were studied by X-ray diffractometer, spectrophotometer, field-scanning electron microscope, and femtosecond (fs) Z-scan technique. The results of the fs Z-scan experiment indicate that the graphene/MoS2/Ag thin films exhibit reverse saturable absorption properties due to the free carrier absorption and two-photon absorption. More importantly, with the increase of DC magnetron sputtering power (from 5 to 15 W), the local surface plasmon resonance effect of the Ag thin films increases, which leads to the enhancement of nonlinear optical properties of the graphene/MoS2/Ag thin films. The nonlinear absorption coefficients of the graphene/MoS2/Ag thin films are increased from 1.14 × 10–10 to 1.8 × 10–10 m/W at 800 nm and from 4.79 × 10–11 to 6.79 × 10–11 m/W at 1,030 nm, and the nonlinear refraction index of the graphene/MoS2/Ag thin films is -4.37 × 10–17∼−4.18 × 10–16 m2/W under the excitation of 800 and 1,030 nm, respectively. Moreover, when the graphene/MoS2/Ag thin films were excited at 800 and 1,030 nm, respectively, the nonlinear figure of merit values of the graphene/MoS2/Ag thin films are increased from 1.23 to 2.91 and from 1.30 to 1.47, which are enough to support the application of the graphene/MoS2/Ag thin films in the field of all-optical switching applications.

Incident wave reflection and transmission caused by the impurity in one-dimensional bead chain are studied. As the number of impurities increases, the energy of the transmitted and reflected waves oscillates periodically. When the number of impurities is so large that its length is greater than the width of the incident wave, the transmission and reflection remain constant. In this paper, the dependence of the energy of transmitted and reflected waves on the number of impurity particles in each segment is studied. It is noted that both the reflection and the transmission depend not only on the numbers and the permutation of the impurity but also on the parameters of the incident wave. This behavior can be used to detect the impurities in the bead chain by measuring the reflection of an incident wave.

The solid-state incandescent light emitting device (SSI-LED) emits the broadband warm white light [1-5]. The light emission principle is the thermal excitation of the nano-resistors formed from the dielectric breakdown of a MOS capacitor with a nm-thick high-k gate dielectric layer [5]. Besides the light emission, the nano-resistor device shows the diode-like characteristics, i.e., current flow in one direction but not the other direction [1]. Since the nano-sized structures are easily subject to the environmental effect, e.g., oxidation in air [6,7], it is important to understand how the temperature and high humidity affect the electric resistance of the nano-resistors in the SSI-LED. MOS capacitors of 50 μm, 100 μm, 200 μm, 300 μm, and 400 μm diameters were fabricated on a pre-cleaned p-type (10-5 cm-3) (100) Si wafer. Each capacitor contains 1) a 9 nm thick zirconium-doped hafnium oxide (ZrHfO) high-k gate dielectric (including the interface layer with Si), 2) an 80 nm thick ITO gate electrode, and 3) a Mo back side contact layer. Nano-resistors, as shown in Figure 1, were formed after the gate dielectric was broken. The current density vs. voltage (J-V) curve of the nano-resistor device was measured between Vg = 0 V and -20 V at room temperature, 50˚C, 80˚C, 100˚C, and 120˚C. The resistance was extracted from the linear portion of the curve, i.e., between -10 V and -18 V. Then, the sample was loaded in an environmental chamber (Associated Environment System BHD-403 7136) under relative humidity 80% at 80 ̊C for 1 hour. The J-V curve was measured in air at room temperature. Figure 2 shows resistances of various sized nano-resistor devices at 50ºC, 80ºC, 100ºC, and 120ºC. With the increase of temperature, the resistance increases. Since the resistance is contributed by elements in the current path, i.e., the ITO gate electrode, nano-resistors, interfaces, and the Si wafer, each of which can affect the result. Although the Mo resistance is affected by the temperature [8], the value is much smaller than that of the nano-resistor device in Fig. 2. The resistance of the p-type Si (1015 cm3) changes little in the room temperature to 120ºC range [9]. The resistance of ITO also remains in the same temperature range [10]. Therefore, the temperature effect must be contributed by nano-resistors and interfaces. Figure 3 shows the size effect on the resistance after the 80% humidity and 80℃ annealing. The resistance decreases nonlinearly with the increase of the diameter. Assuming that all nano-resistors are of the same dimension and evenly distributed underneath the gate electrode of area, the resistance vs. device size relationship should follow the Pouillet’s law of R = ρ⋅L/A [1] where R is the resistance, ρ is the resistivity, L is the length, and A is the cross-sectional area. The prediction curve in Fig. 3 was calculated based on the resistance of a 400 µm diameter device. It deviates from the measured data especially in the small diameter range. It was reported that the density of nano-resistors near the edge of the gate is larger than that in the center region [1]. As the device diameter is reduced, the area ratio of the edge region to the total gate electrode increases. Therefore, the density of the nano-resistors increases with the shrinking of the device size, which results in the reduction of the resistance. Also, nano-resistors near the gate electrode edge may be of different sizes from those away from the edge. Moe detailed discuss of the environmental effect will be presented. Lingguang Liu acknowledges the financial support of National Natural Science Foundation of China (Grant Number 61771382) and the Shaanxi International Science and Technology Cooperation and Exchange program (2018KW-034). [1] Y. Kuo and C.-C. Lin, Appl. Phys. Lett., 102, 031117 (2013). [2] Y. Kuo and C.-C. Lin, ECS. Solid-State Lett., 2, Q59 (2013). [3] Y. Kuo and C.-C. Lin, Solid-State Electron., 89, 120 (2013). [4] C.-C. Lin and Y. Kuo, J. Vac. Sci. Technol. B, 32, 011208 (2014). [5] C.-C. Lin and Y. Kuo, ECS J. Solid State Sci. Technol., 3, Q182 (2014). [6] H. Matsubara, T. Sasada, M. Takenaka and S. Takagi, Appl. Phys. Lett., 93, 032104 (2008). [7] S. A. Moiz, M. M. Ahmed and K. S. Karimov, Jpn. J. Appl. Phys., 44, 1199 (2005). [8] R. A. Holmwood and R. Glang, J. Chem. Eng. Data, 10, 162 (1965). [9] W. D. Callister and D. G. Rethwisch, Mat. Sci. Eng.: an introduction, Wiley & Sons New York (2007). [10] Z. Ovadyahu, B. Ovryn and H. Kraner, J. Electrochem. Soc., 130, 917 (1983). Figure 1

Hydrogen is an ideal energy with little impact on the environment to tackle the intense energy crisis. Development of highly efficient electrocatalysts for low–cost hydrogen production from water splitting is vital for the real-world practical applications. Herein, a three dimensional hierarchical graphdiyne (GDY)@NiFe layered double hydroxide (LDH) heterostructured catalyst toward overall water splitting is developed by coupling NiFe LDH and GDY growth on copper foam (CF). The catalyst exhibits high electrocatalytic activities in both oxygen evolution reaction (OER) and hydrogen evolution reaction with overpotentials of 220 mV and 163 mV at a current density of 10 mA cm−2, respectively. The Tafel slope for OER is 39.33 mV dec−1, which is much lower than that of the only NiFe LDH/CF with a value of 112 mV dec−1. Thus, the GDY@NiFe LDH/CF heterostructure electrocatalyst leads to an improvement in the overall water splitting activity, with a current density of 20 mA cm−2 at the voltage of 1.512 V. Density functional theory calculation indicates that the synergetic effects of 3d orbit of transition metal atoms and carbon–carbon triple bonds in GDY are responsible for the bifunctional excellent electrocatalytic activity for overall water splitting.

Influence of interactions between Laccase and carbon nano-tubes modified by perylene derivative on structural parameters and electrochemical behaviors of immobilized redox protein, was investigated systematically by the means of spectrometry, photography and electro-chemistry. Sophisticated interactions including abutting coordination could result in anomalistic agglomeration of nano-composite with Lac incorporation which displayed better hydrophobicity than free Laccase and high resistance of charge shuttle. It would retard the progress of thermal decomposition of nano-composite and would lead to the formation of composite without emission of fluorescence. Strong binding of Laccase with perylenyl derivative (binding constant: 7.5×104 L/mol) would alter the mechanism of electron transferring. T1 Cu2+ of Laccase in the status of complexation played the intra-molecular electron relay with mid-wave potential at −135.6 mV and demonstrated undesirable dynamics in electron transferring (7.7×10−2 s−1). The catalytic function in oxygen reduction was prohibited for the abutting coordination and only weak catalytic effect could be achieved in the presence of electron relay. The whole catalytic cycle was limited by the mass transferring of electron mediator.

For possessing high tolerance to oxidation and radiation damage under irradiation of high fluence heavy ions, nano-laminated Cr2AlC is a better candidate material when used as the functional material in high temperature and nuclear reactors. In this study, the mono-vacancy defect-related properties in Cr2AlC have been investigated by first-principle calculations. The results indicate that the C vacancy could be easily formed due to its low formation energy. It is inferred that the vacancy-mediated migration in Cr2AlC is energetically most favorable for Al vacancy, which can be a proof for elucidating the good oxidation tolerance of Cr2AlC under an oxidizing environment. The conductivity of Cr2A1C will be reduced by the formation of vacancies, while its theoretical Vickers’ hardness will be slightly increased. On the other hand, the bulk modulus will be increased through the introduction of mono-vacancy, which will have a negative impact on the shear modulus and the brittle performance of Cr2AlC. In view of the present work, we propose that Cr2AlC can be excellent material for the applications in extreme environments according to our study based on the first-principle calculation.

Effects of Fe addition on mechanical properties and microstructures of biodegradable Zn-Mn alloys are unknown yet, which will be revealed in the present study. Minor addition of Fe results in formation of (Fe, Mn)Zn13 phase, which can have a (Fe, Mn)Zn13/MnZn13 core/shell structure. The core and the shell exhibit a coherent orientation relationship (OR). Between them, there exists a thin interlayer with an irrational OR with respect to either the core or the shell. Although the as-cast alloys are very brittle, their ductilities and strengths can be significantly improved through hot rolling, owing to significant grain refinement of Zn matrix and refinement of the second phase particles. Elongation of the hot-rolled Zn-1Mn-0.1Fe alloy is about 4.8 times of that of the hot-rolled Zn-1Mn-0.5Fe alloy, indicating that ductility of Zn-Mn-Fe alloy is very sensitive to Fe content. Keywords: Alloy design, Thermomechanical processing, Microstructure, Transmission electron microscopy, (Fe, Mn)Zn13

International audience; We report on the impact of the central heteroatom on structural, electronic, and spectroscopic properties of a series of spirofluorene‐bridged heterotriangulenes and provide a detailed study on their aggregates. The in‐depth analysis of their molecular structure by NMR spectroscopy and X‐ray crystallography was further complemented by density functional theory calculations. With the aid of extensive photophysical analysis the complex fluorescence spectra were deconvoluted showing contributions from the peripheral fluorenes and the heteroaromatic cores. Beyond the molecular scale, we examined the aggregation behavior of these heterotriangulenes in THF/H2O mixtures and analyzed the aggregates by static and dynamic light scattering. The excited‐state interactions within the aggregates were found to be similar to those found in the solid state. A plethora of morphologies and superstructures were observed by scanning electron microscopy of drop‐casted dispersions.

Porous shape‐persistent organic cages have become the object of interest in recent years because they are soluble and thus processable from solution. A variety of cages can be achieved by applying dynamic covalent chemistry (DCC), but they are less chemically stable. Here the transformation of a salicylimine cage into a quinoline cage by a twelve‐fold Povarov reaction as the key step is described. Besides the chemical stability of the cage over a broad pH regime, it shows a unique absorption and emission depending on acid concentration. Furthermore, thin films for the vapor detection of acids were investigated, showing color switches from pale‐yellow to red, and characteristic emission profiles., Cage to cage: Soluble, porous, and chemically stable quinoline cages are synthesized from salicylimine cages in one post‐synthetic step. The cages show characteristic acidochromic behavior in bulk and solution, and as thin‐films.

As-prepared magnetic nano-composite with Fe3O4 as core and carboxymethylated Chitosan as shell was proposed to act as matrix to co-immobilize electron relay and myoglobin by the means of chemical coupling. Subsequently Mb based bio-cathode was fabricated through the procedure of drop-casting in the presence of external magnet and was examined its performance in direct electron transferring and catalysis in electro-reduction of H2O2 with spectrometric and electro-chemical methods. Analysis in results indicated adjacent complexations between hetero-atoms in polymer and cofactors in enzyme/redox site of electron mediator would pose great impact on spectroscopic and electrochemical features of immobilized protein. These interactions would alter the path of electron shuttle and mechanism of catalysis.

A design of printed IFA (Inverted-F Antenna) for WLAN/5G C-band application is proposed. The antenna is printed on the two sides of the FR4 substrate, and the antenna parts on the two sides are connected by via. The antenna consists of 3-arms on the front and back sides of the substrate. The 3-arms of IFA can resonate some modes to match the required bands for applications. From the results of the antenna, it can be applied to the operating bands covering WLAN 2.4GHz/ 5.2GHz/ 5.8GHz bands and 5G C-Band (3.4–3.6 GHz) applications.

Porous organic polymers (POPs) are chemically and thermally robust materials and have been often investigated for their gas sorption properties. From the related field of metal–organic frameworks (MOFs) it is known that open ligation sites at metal centers can enhance the performance of gas sorption significantly, especially the selectivity toward one gas of a binary mixture, such as CO2/N2 or CO2/CH4. POPs that contain metal centers are rarer. One possibility to introduce metals into POPs is by the synthesis of metal-assisted salphen organic frameworks (MaSOFs), where the framework development is associated with the formation of the metal–salphen pockets. Based on a hexakissalicylaldehyde, a variety of three-dimensional isostructural porous MaSOFs with different metal ions (Zn2+, Ni2+, Cu2+, Pd2+, and Pt2+) are introduced. All compounds show a very similar pore structure and comparable specific surface areas, which make these MaSOFs ideal candidates to study the influence of the nature of the incorporate...

The beryllide Be12Ti is considered to be the most promising candidate material for advanced plasma facing materials in future fusion reactors because of its excellent performance. In this work, first-principles calculations were conducted to gain insight into the retention and diffusion behavior of transmutation H and He atoms in Be12Ti. The solution energy and migration energy of single impurity H/He atoms were computed to study the behavior of their retention and diffusion. Among seven stable interstitial sites, H atoms preferentially occupy the octahedral interstitial site, Ioct, whereas He atoms preferentially occupy the dodecahedral interstitial site, Idode. The solubility of H is much higher than that of He in Be12Ti. When monovacancy is generated, H atoms preferentially stay in the vicinity of Be1 vacancies, while He atoms tend to reside in the center of Ti vacancies. The migration energy barrier of a single He atom between first near-neighbor Idode sites is 0.35 eV. For H atoms, the migration energy barrier from Idode to Itetra2 is 0.45 eV. The barrier along the paths Itri1–Idode–Itri1 is 0.38 eV. When a Be3 vacancy is introduced as the neighbour of Itri1, the migration energy barrier increases to 0.77 eV. These results indicate that vacancies can trap impurity atoms and may act as seeds for bubble formation.

First principles calculations have been performed to investigate the synergetic effect of H and He impurities with vacancies in Ti3AlC2. The configurations and energetics of Hn–He–VAl complexes (n ≤ 4) and He–He/He–H/H–H interactions have been studied. It is found that the impurity H atom prefers to occupy the tetrahedral interstitial site (Itetr-3), but the He atom prefers to occupy the octahedral interstitial site (Ioct-4) in perfect Ti3AlC2. Within a pre-existing Al vacancy, the most favorable site for a He atom is close to tetr-site, meanwhile the H atom preferentially deviates from the vacancy center with the separation 1.3 A along the 〈001〉 direction. He–H and He–He show a weakly attractive interaction, but weak repulsion occurs in the H–H interaction, which is different from the case of Ti3SiC2. The He–VAl complex plays an important role in the trapping of H atoms. The He–VAl cluster can trap up to three H atoms in the absence of H2 molecules, which leads to the formation of a H–He hybridized bubble. Thus, the He atom can subsequently suppress further aggregation of H atoms and block hydrogen embrittlement and volume swelling.

Dynamics of heterogeneous catalysis on oxygen reduction for Lac based electrode capped with a layer of Chitosan-multi-wall carbon nano-tubes complex in the presence of dissolved mediator, was investigated on the basis of precondition that the detainment of substrate and mediator could be neglected. Rates of steps involved in the whole catalytic cycle were determined by the means of UV–Vis spectroscopy, atomic adsorption spectroscopy, linear sweeping voltammetry and cyclic voltammetry in combination with rotating disk electrode technique. These kinetic parameters were normalized under the same dimension. Thus rate determining step was verified to be the diffusion of external mediator. Results also revealed the fact from analysis in changes of morphology and electric conductivity after protein incorporation into nano-composite that random adsorption of enzyme molecules on the conductive support resulted in the decrease in conductive area of nano-composite and hindered the direct electron transfer between active sites in enzyme molecules and conductive matrix. Non-oriented arrangement of protein molecules on the matrix also crippled the mechanical stability of nano-complex with enzyme resulting from weak interaction between incorporated protein molecules and carrier. Catalytic effect on dissolved oxygen reduction reaction for electrode which was over-coated by a layer of nano-complex with immobilized Laccase consisting of Chitosan and multi wall carbon nano-tubes, were found to be restrained by diffusion of electron relay.

The effects of both the ac and the dc external driving forces on the production of screw dislocations are studied by employing the two-dimensional Frenkel–Kontorova model. The ac force is introduced in the model as a way to describe external periodic disturbances or artificial periodic forces. We find that the appearance of the screw dislocation is influenced by the frequency and amplitude of the ac force. It is shown that the screw dislocation can be easily produced by either the lower frequency or the larger amplitude of the ac force.

In this paper, a design of dual-polarization Yagi- like multilayered slot antenna is proposed. The Operating band of the design is covering the band of 3.4 to 3.6 GHz for fifth- generation (5G) C-band. The antenna consists of a ring-shaped slot, two directors by using ring-shaped slot, and a pair of double L-shaped feeds on the back to excited slot antenna, which is forming a design of vertically stacked antenna. The overall size of Yagi antenna is 42 × 42 × 60 mm3. The introduction of the director 2 with a thin PLA (Polylactic Acid) coating and with 8 small circular apertures located on the slot is to enhance the impedance match. Simulated and measured S11 and S22 results are below of -10dB and S21 for the two feeds are less than -20dB. The simulated antenna gains of the design achieve 9.4-10.7dBi. Since port1 and port2 are almost symmetrical, both horizontal and vertical planes provide a stable radiation pattern. So it is good candidate for 5G C-band wireless system.

An overdamped three-layer model with incommensurate structure consisting of two harmonic chains which both move over the substrate potential is studied in the presence of an external (Formula presented.) driving force. The force is applied only on the upper harmonic chain, and dynamics of the middle layer is examined. The results show that the dynamical mode-locking appears not only in the upper layer but also in the middle one. The behavior of the middle layer is strongly determined by the amplitude and frequency of the ac force, and the phase diagram which presents pinned, dynamical mode-locking and sliding regimes as a function of system parameters are given. Contrary to the standard case, critical depinning force and steps exhibit anomalous behavior. Particles trajectories have been analyzed which showed very different motion of particles from the one which usually appears in systems under (Formula presented.) forces.

The transmission and the reflection of a shock wave by one or several impurities in viscoelastic bead chains is studied in the present paper. There is only one reflected wave for a single impurity. The amplitude of the beads oscillation increases as the initial velocity of the boundaries beads increases, while it decreases as the viscosity coefficient increases. Two reflected waves will be produced if the impurity number is larger than a critical value. This critical value depends on both the initial velocity and the viscosity coefficient. In addition, the maximum amplitude of reflected wave is a constant, when the viscosity coefficient is large enough.

2.5D assembly, a package with stacking GPU and HBM chips onto through silicon via interposer (TSI), then mounted onto organic substrate is now mass produced and dedicated package solution for high performance and large volume numerical calculation applications. However, high cost for TSI wafer and substrate, also the large/thick package dimension and long assembly cycle time of 2.5D package are also limit its penetration of high performance applications. The applications using 2.5D package are continuously drive OSATs to thinner the outline dimension and assembly cycle time, especially the cost of 2.5D package, wish to apply this assembly platform on a wider field.A directly derivative of 2.5D package with thinner thickness/cost is to eliminate the organic substrate, and make the function of organic substrate as an RDL circuits onto the TSV interposer, so called TSI-FCBGA (patented). As a package without organic substrate, the outline dimension of this package will be only half of original structure. It will also shorten the cycle time of secondary assembly processes of chip modules onto organic substrate. As to eliminate organic substrate, the original at least 6 layers circuits on it is now re-distributed onto TSV interposer will make the RDL circuits on TSV interposer with fine line space and pitch to ensure matchable I/O before and after eliminating the organic substrate. Thus, the interconnection solder ball size and pitch will be smaller than that of original package with organic substrate. However, there is no reliability data available for this TSI-FCBGA package with smaller solder ball size and pitch.For the work of this paper, we modified platform of 2.5D package chip module with changing C4 side micro bump to solder ball, as a test vehicle of TSI-FCBGA, and demonstrated the board level reliability of it with different solder ball type, size, pitch, also molded solder ball on TSV interposer with daisy chain circuits. The results show the board level reliability of this thinner 2.5D package can pass mostly 733 thermal cycles with definite solder ball types and properties, though it is a little worse than original 2.5D package with organic substrate. Simulations are furtherly executed to find better structure of UBM and RDLs for future study.

Transportation of charges, mass and heat of dust particles in a weakly ionized plasma is studied in the present paper. The dependence of electric conductivity, diffusion coefficient and heat conduction coefficient of dust particles on total number density and temperature of dust particles, number density and mass of neutrals, as well as collision cross section area between dust particles and neutrals are given. Effects of dust size distribution on electric conductivity, diffusion coefficient and heat conduction coefficient of dust particles have also been investigated. It is noted that they increase as the mean value of radius of dust particles increases. They increase as difference between maximum and minimum values of dust particles increases when density of the small grains is smaller than that of large grains. However, they decrease as difference between maximum and minimum values of dust particles increases when density of the small grains is larger than that of large grains.

A two-dimensional particle-in-cell simulation is carried out to study the focusing effects of the long proton beam propagating in background plasmas. It is found that the smooth beam, with the long length and the small density gradient profile, is focused to high density. The sharp beam, with long length and the large density gradient profile, is modulated into many high density and periodic short beam pulses due to the wakefield induced by the beam. In addition, increasing the plasma density and adopting the non-uniform plasmas are the effective ways to reduce the wakefield.

We use a chain of harmonically interacting atoms confined between two sinusoidal substrate potentials in which the top substrate is driven by the driving force. This system is closely related to physical situations with confined lubricant films. The dependence of the static friction force on the system parameters such as the equilibrium spacing and the strength is presented. It is found that the better lubricant films are materials with larger interatomic interaction strength, and the lubricant structure is in the certain region.

The CdSe/Al2O3/Ag composite films were deposited by magnetron sputtering and spin coating, and some samples were annealed at 450 °C. The linear absorption peak of annealed samples showed a clear redshift behavior. The femtosecond Z-scan was adopted to study the ultrafast third-order nonlinear optical response of the CdSe/Al2O3/Ag composite films. In the present study, the nonlinear properties of the composite films were 104 times higher than single CdSe quantum dots, and the properties exhibited by the unannealed samples were better than annealed samples. The increase in laser energy causes an enhancement in saturation absorption and self-focusing properties. The effects of Ag nanoparticles sputtering conditions and CdSe quantum dots content on the optical properties of the samples were also investigated. Unannealed CdSe/Al2O3/Ag composite films with Ag nanoparticles (P = 15 W) and one layer of CdSe quantum dots have the maximum value of β and χ 3 ,which are -4.80 × 10−9m/W and 3.82 × 10−9esu. Composite films can be used in optical sensing, information and communication technologies, and many other optoelectronic applications.

First-principles calculations are performed to study the effects of defect on the structure and electronic properties of Ti3SiC2. The calculations show that the formation energy of Si vacancy is minimal compared with the Ti or C vacancies in Ti3SiC2. The defects of Si layer also can be formed under high-temperature or irradiation environments. The C-layers or Ti-layers are almost impossible to form. If the Si vacancy or Si layers are formed, they prefer to be substituted by the O and H atoms to form the MXene structure, and the unit cell of Ti3SiC2 lattice constant decreases in c-direction. However, it has quite slight effect on electronic properties of Ti3SiC2. The He impurities are almost impossible to occupy the Si vacancies, because the formation energy are 50.860 eV for one layer of Si atoms substituted by the He atoms. This type of defect leads to the lattice constant of Ti3SiC2 in c-direction increasing considerably. Therefore, Ti3SiC2 is a suitable candidate for nuclear materials because of the high-formation energies of He impurities under irradiation environment.

Through the process of magnetron sputtering and spin-coating, CdSe/Al2O3/Ag and CdSe/PMMA/Ag composite films were fabricated. All the composite films' linear optical performances, morphology and structure have been concluded. Composite films' nonlinear refraction and absorption properties were investigated by fs Z-scan technique. When the laser energy is increased from 100nj to 500nj, the CdSe/PMMA/Ag composite films' saturated absorption (SA) are enhanced, and the CdSe/Al2O3/Ag composite films are converted from SA to reverse saturated absorption (RSA), the nonlinear absorption behavior can be explained by a three-level model. At 300nj laser energy, all the composite films exhibit SA. Both the composite films' nonlinear refraction and absorption were enhanced with the increasing of Ag nanoparticles (NPs) sputtering power. However, with the layers of CdSe quantum dots (QDs) increasing, the composite films' nonlinear absorption and refractive indexes were both decreased. Moreover, the CdSe/PMMA/Ag composite films’ third-order nonlinear polarization index, as compared with that of the CdSe/Al2O3/Ag composite films, are about ten times higher. Composite films can be used in many types of signal processing as well as in photonics and optoelectronic applications.

Zn alloys containing Fe element suffer from the detrimental effect of coarse FeZn13 or (Fe, Mn)Zn13 second phase in Zn matrix on mechanical properties, especially on ductility. The key reasons are the peritectic reaction of Fe and Zn at high temperatures and negligible solid solubility of Fe in Zn at low temperatures. Taking a recently developed biodegradable Zn–Mn–Fe alloy as the base alloy, it is revealed that minor additions of Y and Nd rare-earth elements can significantly refine (Fe, Mn)Zn13 phase. With a total addition of 0.14%, the average size of blocky (Fe, Mn)Zn13 particles reduces about 43%, while the average length of lath-like (Fe, Mn)Zn13 particles reduces about 50%. Sphere-like (Y, Nd)Zn12 particles serve as effective nucleating agents for (Fe, Mn)Zn13 and MnZn13 with nearly the same lattice parameters. As a result, yield strength, the ultimate tensile strength, and elongation to failure of the base alloy increase by 30 MPa, 27 MPa, and 6%, respectively. Cell viabilities of the alloys with or without rare-earth additions are all over 100%, indicating good biocompatibility.

In this paper, preliminary neutron physical properties of ceramic fast reactor (CFR) are simulated and analyzed. The CFR core consists of ceramic materials, including nuclear fuels, coolants, structural materials, reflective and absorption materials. These ceramics improve inherent safety levels substantially, increase breeding performance, and enhance the power-generation efficiency. The CFR has the potential to operate and breed more than 30 years. The performance of the CFR was simulated focusing on neutron-related effects. The parameters discussed contain fast neutron energy spectrum, the ideal effective multiplication-factor, nuclides mass changes, breeding performance, operation mode, etc. Furthermore, the strengths of the proposed reactor system are discussed. In the future nuclear energy system, CFR may be one of the existing alternative novel reactor type.

The multi-chip module assembled with a composite layer of thin film on top of organic substrate is presented in this paper. This is a new-arising assembly technology with equivalent electrical performance of 2.5D package but much simplified supply-chain processes. We name this package as 2.1D package which converts the silicon interposer on the substrate. In this paper, the implementation of 2.1D technology on the monolithic, daisy-chain test vehicle is described. We employed thermal compression bonding (TCB) to mount two large dies with minimum 40 ?m-pitch micro bumps onto 45 x 45 mm organic substrate using 2/2 µm line width/space (L/S). Thermally induced misalignment, substrate warpage and the ELK (Extreme Low-K) stress during micro bumps joining with micro pads on substrate were evaluated. The mechanism of micro bump misalignment during solder formation has been experimentally and numerical validated by TCB and conventional mass reflow (MR) process. Finite element analyses were conducted to understand the 2.1D package warpage and stress behaviors, and hence defined better materials and process parameters. Simulation results showed that micro bump joining by TCB has 45% misalignment improvement as compared to MR process. In stress simulation results, the ELK layer stress of micro bump using TCB has a 59% reduction with reference to MR. In addition, the warpage behavior of fine-line organic substrate and 2.1D full package were measured using conventional shadow moire system. Results showed that the warpage variation of thin-film coated substrates was very stable within micro pads area that has less than 10 µm differences under high temperature period (120~260 °C). However, the package moire results showed that the thermally attaching of stiffener ring could significantly affect the global package warpage based on moire contours and warpage distributions. The reliability of this developed 2.1D, multi-chip test vehicle using TCB assembling processes was validated as well. This package passed MSL4 preconditioning and 1000 thermal cycles using G-conditions (-40~125 °C).

Flip chip (FC) assembly technology was developed by IBM in 1960s and widely used in high functional performances of electronic devices in computer, military, mobile, automobile etc. The use of solder bumps to make electrical connection between the substrate and chip can provide shorter path and reduce latency issues as compared to wire bonding. Additionally, flip chip is an area array bonding, which allows high I/O (Input/Output) density within a single die, and thus driving the semiconductor scaling process. Over the decades, the number of interconnection within flip chip devices has been increased from hundreds to half million bump joints. For the purpose to achieving the massive high I/O counts, the miniature of bump size and bump pitch plays a significant role, and also face technology challenges. Chip interconnection bumps technology has been evolved over fifty years. Generally, it could be divided into three generations in according to the connection method. The first generation typically has the bump pitch over 130μm, while the second generation's bump pitch is within a range from 40 to 130 μm. And the most recent one (the third generation) has been developed to be smaller than 30μm. Each generation has unique bonding technology and encapsulation materials to make different assembly packages and form factors. For the bump pitch over 130μm, which is normally composed of solder ball, is so called controller collapse chip connect (C4) bumps. The bumps in the device, up to nearly thousand counts, are usually bonded on to ceramic or organic substrate using flip chip bonder with fluxing and reflow soldering processes. Further, flux cleaning is introduced to remove flux residue, which is followed by the underfill or mold encapsulation process to protect the solder connections. Flip Chip Ball Grid Array (FCBGA) and Flip Chip Chip Scale Package (FCCSP) are the classic two package types of this C4 joint generation. As for the interconnection technology with bump pitch between 40 to 130μm, which is so-called micro bump or chip connection (C2) bumps, the thermal-mechanical warpage and bonding precision are the major challenges. The copper pillar with thinner solder tip is generally produced to meet the finer pitch requirements. However, the collapsing process during soldering is hard to compensate the warpage induced by CTE-mismatch between chips and substrates, which drives the implementation of through silicon interposer (TSI) to be a solution for the thermal mismatch concern. Additionally, thermal-compression bonding (TCB) technology are high precision bonder are essential requirements for die bonding process. Owing to the miniaturization of bump scaling, the flux cleaning process is getting hard to achieve fully cleaned inside the package. Thus, the demand for fluxless or non-clean flux are getting popular. Furthermore, the new encapsulated materials like non-conduction paste (NCP) or non-conductive film (NCF) are now being applied to enable the fine-pitch assembly and the 2.5D packages. The 3DIC assembly, the most advanced package type, is moving forward to design the bump pitch to 30μm and below. The existing soldering process can no longer support this new bump scaling and high precision requirement due to the physical limitation of solder tip. So the processes such as direct Cu-to-Cu (Copper-to-Copper) bonding using thermal diffusion process under ultra-high vacuum environments and the electroless plating are getting more attention in recent years. The studies on Cu-to-Cu interconnection for ultra-fine pitch bonding are still in exploration stage and already showing some positive results. The particle control for finer pitch and smaller interconnection size will become a major consideration factor for yield. In view of flip chip technology evolution, this paper is going to discuss the requirements of these interconnections in term of materials, machines, environments, and processes. Further, the changing of bump interconnection in flip chip package will be discussed as well.

Recent researches have already shown that graphene can be a very promising candidate for reducing friction and wear by being coated on various moving mechanical assemblies. Although its excellent lubricative properties have been examined in different environments experimentally, the effect of conditions on graphene tribology performance are not well-understood. This research demonstrates the friction and wear mechanisms of graphene at nanoscale by first-principles calculations performed under two different conditions: in vacuum and in hydrogen. Besides, this report has revealed the difference of tribological performance between graphene coating and graphite powder in vacuum. It is shown that the graphene coating has lower adhesion than graphite powder because of less dangling bonds. Furthermore, with the perfect lamellar structure and low surface energy, graphene sheets exhibits promising wear resistance. Additionally, the adhesion and wear resistance of graphene sheets can be improved by hydrogen-induced flexible electrons. The computational simulations show that the higher adhesion originates from hydrogen adsorption. It is really helpful for the ruptured graphene to extend the wear life by hydrogen passivation.

The design of a compact, flexible and wearable dual band monopole patch antenna is presented. The antenna has low profile and printed on common denim fabric (60 mm × 60 mm × 1 mm) with permittivity (1.7) and loss tangent (0.024). The performance of the fabricated unit is observed under different deformations in free space as well as when placed on different parts of human body. The antenna has presented durability and robustness with only slight differences in measured return losses when placed in proximity to human body. Simulations for 10 g average Specific Absorption Rate (SAR) is performed for different input powers up to 100 milliWatt. Simulated SAR is increasing by increasing the incident power, as well as the skin tissue is the most affected part of the body.

A spallation target is one of the three core parts of the accelerator driven subcritical system (ADS), which has already been investigated for decades. Recently, a gravity-driven Dense Granular-flow Target (DGT) is proposed, which consists of a cylindrical hopper and an internal coaxial cylindrical beam pipe. The research on the flow rate and free surface are important for the design of the target whether in Heavy Liquid Metal (HLM) targets or the DGT. In this paper, the relations of flow rate and the geometry of the DGT are investigated. Simulations based on the discrete element method (DEM) implementing on Graphics Processing Units (GPUs) and experiments are both performed. It is found that the existence of an internal pipe doesn’t influence the flow rate when the distance from the bottom of the pipe to orifice is large enough even in a larger system. Meanwhile, snapshots of the free surface formed just below the beam pipe are given. It is observed that the free surface is stable over time. The entire research is meaningful for the design of DGT.

The formation and migration energies of the mono-vacancies, foreign impurities (H, He and O atoms) and interstitials in Ti2AlN have been investigated using first principles calculations. The results have shown that the mono-vacancy formation is energetically most favorable for the Al atom. There are three stable configurations for the foreign impurities, the Al-layer triangle center site, the interstitial site (⅓,⅔,0.6578) and the vacancy site. It was also found that the O substitution is easily formed. For interstitials, the octahedral interstitial (Ti, N, H or O) and Al-layer triangle interstitial (Al or He) sites were observed in our simulation. Moreover, the H, O and N interstitials are dominant in Ti2AlN. These results could provide theoretical guidance for future experiments and for the application of Ti2AlN.

ZSM-5/MCM-41 composite zeolites were synthesized by a two-step hydrothermal crystallization procedure using binary templates of cetyltrimethylammonium bromide (CTAB) and tetrapropylammonium hydroxide (TPAOH). The effects of aluminum content on zeolite particle morphology and structure were studied. Powder X-ray diffraction (XRD) results showed that the composite zeolites are of both MCM-41 structure and zeolitic MFI structure. SEM results showed that the morphology of composite zeolites is significantly influenced by the aluminum content.

The monovacancy formation energies of each element Nb, Ge and C in the MAX phase Nb2GeC are obtained by ab initio calculation in the present paper. It is noted that the vacancy of each element has a slight effect on the hybridization bonding. If there is a vacancy of either Ge or C, the hybridization bonding will be slightly reduced. However, if there is a Nb vacancy, the hybridization bonding will be increased between the d-orbital and p-orbital. In contrast, the vacancies can substantially reduce the conductivity of the MAX phase Nb2GeC. It is also noted that if there is a vacancy of either Ge or C, the hardness of the Nb2GeC decreases, while it is increased if there is a Nb vacancy.

By considering the dependence of the viscosity on the relative velocity between adjacent beads, the shock wave structure in a one-dimensional nonlinear granular system is studied in the present pap...