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Considering energy dependence of the barrier radius in heavy-ion fusion reactions, a modified Siwek-Wilczy\'{n}ski (MSW) fusion cross section formula is proposed. With the MSW formula, the fusion barrier parameters for 367 reaction systems are systematically extracted, based on 443 datasets of measured cross sections. We find that the fusion excitation functions for about $60\%$ reaction systems can be better described by introducing the energy dependence of the barrier radius which is due to the dynamical effects at energies near and below the barrier. Considering both the influence of the geometry radii and that of the reduced de Broglie wavelength of the colliding nuclei, the barrier heights are well reproduced with only one model parameter. The extracted barrier radius parameters linearly decrease with the effective fissility parameter, and the width of the barrier distribution relates to the barrier height and as well as the reduced de Broglie wavelength at energies around the Coulomb barrier., Comment: 9 figures, 1 table, accepted for publication in Atomic Data and Nuclear Data Tables

Pre-neutron fragment mass yields in the vicinity of the thermal neutron energy are highly important for applications because of the larger fission cross sections of the U(n, f) and Pu(n, f) reactions. In this paper, pre-neutron fragment mass yields at incident energies from thermal up to 20 MeV are systematically studied using an empirical fission potential (EFP) model, the potential parameters of which are obtained from the measured data. The energy dependences of the peaks and valleys of the pre-neutron fragment mass yields are described by exponential and linear functions for the U(n, f) and Pu(n, f) reactions, respectively. The energy dependences of the evaporation neutrons, which play a crucial role in the reasonable description of pre-neutron fragment mass yields, are also obtained from the fission cross sections. The pre-neutron fragment mass yields in this study are not only consistent with the results of previous studies in regions of several MeVs but also agree well with existing measured data at incident energies from thermal up to 20 MeV. The results show that the feasibility of this EFP model is verified in this extended energy region.

Continuous development and advancement in modern detection technologies have increased the demand for multiband (e.g., visual and infrared) compatible camouflage. However, challenges exist in the requirements of incompatible structure resulting from the adaptation to different camouflage effects. This study is inspired by the light absorption structure of butterfly wing scales and demonstrates a porous anodic alumina/aluminum flake powder material prepared by a microscopic powder anodic oxidation technique for visual and infrared camouflage. The fabricated structures manipulate a compromise condition for visual camouflage by low reflectance (

In mesoporous perovskite solar cells ( mp-PSCs), an electron transport layer (ETL) plays an important role in charge extraction and transportation, and also its structure largely affects the crystallization and optical property of perovskite films. At present, the performance of PSCs based mesoporous SnO2 ( mp-SnO2) still lags behind that based planar SnO2 due to problems in the fabrication process of mp-SnO2. Herein, a well-organized monolayer SnO2 inverse opal (SIO) is prepared as the structured ETL for perovskite solar cells. The unique periodic SIO structure exhibits an obvious optical coupling phenomenon, which enhances the light absorption of the perovskite layer. Furthermore, the well-organized SIO structure with appropriate pore size triggers the confined crystallization of perovskite films and optimizes the interface of SnO2/perovskites, suppressing the interfacial electron–hole recombination. As a result, the power conversion efficiency of mp-PSCs fabricated by the monolayer SIO is boosted from 19.63% to 22.01%. This work provides a creative strategy for construction of high-efficiency mp-PSCs based on SnO2.

As a novel family of 2D materials, MXenes are supposed to play a vital role in optoelectronic devices and systems due to their high conductivity, good optical properties, and favorable compatibility with water and organic solvents. However, the application of MXenes in highly sensitive photodetection is far scarcely investigated. Here, we demonstrate high-quality Ti3C2Tx/GaAs Schottky junction by simply dripping Ti3C2Tx MXene solution on a pre-patterned GaAs substrate. Owing to the wide absorption of MXene and the good quality junction, the self-driven Ti3C2Tx/GaAs Schottky junction photodetector with an impressive performance is realized. The assembled photodetector exhibits a high sensitivity over a wide waveband with a good responsivity of ~1.46 A/W, a large specific detectivity of ~1.23 × 1013 Jones, and a high Ilight/Idark ratio of 5.6 × 105. Significantly, the photodetector is capable of sensing infrared light signal up to 980 nm which exceeds the absorption edge of GaAs (874 nm) due to the generation of hot electrons in Ti3C2Tx MXene film. Given the superior device performance along with a simple and facile fabrication method, the Ti3C2Tx/GaAs Schottky junction photodetector may find the great potential in high performance broadband, self-driven photodetection applications.

The electrocatalytic N2 reduction reaction (NRR) is a very attractive yet challenging route for sustainable NH3 synthesis under ambient conditions, for which efficient catalysts are required due to the highly strong NN bond. In this work, B decorated C9N4 monolayer (B-C9N4) for NRR is studied by using first-principles calculations. It is found that the inert N2 can be sufficiently activated through the electron “acceptance-donation” pattern between N2 and the B dopant. The subsequent N2 reduction prefers the alternating mechanism, and the reduction of *N2 to *N2H is the potential-limiting step with an overpotential of 0.56 V. Furthermore, B-C9N4 exhibits a metallic nature, which can promote charge transfer during the reduction process. The stability of B-C9N4 can be confirmed by the calculated B adsorption energies and the ab initio molecular dynamic simulation. Consequently, owing to its high activity, good electrical conductivity, and excellent stability, B-C9N4 is a promising metal-free N2 reduction catalyst. Our work not only provides an efficient electrocatalyst for NH3 production, but also opens up a promising avenue to develop highly active and robust metal-free catalysts for other applications.

First-principles calculations have been carried out to explore the effect of atom surface adsorption on the electronic, magnetic, and optical properties of the germanium phosphide (GeP) monolayer. It is shown that the GeP monolayer exhibits good adsorption capability to all the selected adatoms and can preserve the structural integrity upon the adsorption of most adatoms. The adatoms can bring out diverse electronic properties to the GeP monolayer. The H, Li, Na, K, and Al adatoms donate electrons to the GeP monolayer and result in its metallization. The other adatoms do not change the semiconducting nature of the GeP monolayer and will induce midgap states (Mg, Ca, Si, Ge, Ag, and Au) or reduce the bandgaps (Ni, Pd, and Pt). The B, N, P, As, V, Cr, Mn, Fe, and Co adatoms induce spin magnetic moments into the GeP monolayer. Especially, the spin magnetic moments are mainly located on the adatoms for the GeP decorated with the V, Cr, Mn, Fe, and Co atoms. As a result, the dilute magnetic semiconductor can be obtained. In addition, all the adatoms decrease the work function, except O. Thus, some effects on the optical properties are highly expected. The GeP monolayer exhibits a wide range of light absorption and the Mg, Si, Ge, Cu, Ag, Au, and Pt adatoms can further redshift the absorption edge of the GeP monolayer along the x and y directions. Our calculations provide an effective method to modulate the electronic, magnetic, and optical properties of the GeP monolayer for device applications.

The odd–even effect of fragmentation cross sections is studied by improved quantum molecular dynamics model and the GEMINI statistical decay model for reactions 36Ar and 40Ar on C, Al, Cu and Pb targets at 400 A MeV. The odd–even effect is produced in the de-excitation process. The pairing energy plays an important role for the odd–even effect. The odd–even effect disappears without the pairing energy. The excitation energy of prefragments is researched. The odd–even effect for proton is produced obviously at low excitation energy for 36Ar projectile. The odd–even effect is stronger for the neutron fragmentation than the proton one.

Molybdenum disulfide (MoS2) has received widespread attention in recent years due to its exciting properties. However, the practical applications of MoS2 in optoelectronic devices are impeded by the power supply problem, the lack of flexibility, and the low light absorption for planar nanosheets and nanosheet arrays. Inspired by the elaborate architecture of the flower Tagetes erecta L., in this work, a self-assembled divergent MoS2 nanoflower (MoS2_F) with quasi-spherical symmetry is successfully synthesized by a facile one-step hydrothermal method. It is of significance that coupled with asymmetric silver electrodes and packaged by polymethyl methacrylate (PMMA), a self-powered flexible photodetector (PD) based on MoS2_F is actualized and shows an excellent flexible photoresponse performance at zero bias voltage. The divergent structure with quasi-spherical symmetry enables the MoS2_F to achieve strong broadband and omnidirectional absorption (92.7%) and ensures that the MoS2_F maintains the same physical contact on a different bending degree. Intriguingly, excellent flexibility and stability have been achieved as MoS2_F PD retains 91.4% of the initial efficiency even when bent to 151° and retains 92.5% of the initial efficiency even after 1000 bending cycles. Therefore, by a low-cost process, this work demonstrates an innovative avenue to fabricate a self-powered flexible photodetector with excellent light absorption, broadband response, flexibility, and stability, which is of great practical significance for optoelectronic applications in various environments.

The energy dissipation processes in multinucleon transfer reactions of $^{136}$Xe+$^{198}$Pt at incident energies Elab=5.59 and 7.98 MeV/nucleon are investigated by using the improved quantum molecular dynamics model. The total-kinetic-energy-mass (TKE-Mass) distributions, the total kinetic energy loss (TKEL) distributions, and the excitation energy distributions of the primary binary products under different contact time scales of the reaction partners are analyzed. It shows that the value of the energy dissipation has an increasing trend over contact time. The quasielastic, the deep-inelastic, and the quasifission events can be roughly distinguished by the contact time. By analysing the correlation between the isotopic cross sections and the contact time, we find that the neutron-rich nuclei are produced in the deep-inelastic collisions.

Metal oxide gas sensors with porous structures are widely used in numerous applications ranging from health monitoring and medical detection to safety; in this study, we report a highly sensitive SnO2 gas sensor with a multi-level tube/pore structure prepared via biomimetic technology using flax waste as a bio-template and a simple wet chemical process combined with subsequent annealing. Indeed, MLTPS not only maintained and improved the excellence of porous structure gas sensing materials with abundant active sites and large surface-to-volume ratios, but also overcame the deficiency of the lack of gas diffusion channels in porous gas sensing materials. Thus, this novel multi-level tube/pore SnO2 gas sensor exhibited significantly enhanced sensing performance, e.g. an ultra-low response concentration (250 ppb), a high response (87.9), a fast response (9.2 s), a low operating temperature (130 °C) and good stability, for formaldehyde. On the basis of these results, via the reuse of agricultural waste, this study provides a new concept for the low-cost synthesis of environmentally friendly and effective multi-level tube/pore gas sensor materials.

First-principles calculations have been performed to study the modulation of the electronic and optical properties of the black phosphorous carbide monolayer (b-PC) by the adsorption of O2, H2O, NO2, and NH3 molecules. All the molecules are weakly physisorbed on the surface of the b-PC, which act as electron acceptors except NH3. Especially, O2 and NO2 molecules can introduce deep acceptor states in the bandgap of the b-PC. The effects of the external electric field and the in-plane strain were further studied. For the b-PC with the adsorbed O2, the typical p-type doping can be achieved under an appropriate external electric field. However, the b-PC with the adsorbed NO2 is the most susceptible to the in-plane strain, as evidenced by the significant changes in the adsorption energy and the charge transfer under the compressive strain. In addition, the optical absorption of the b-PC can be significantly enhanced upon the adsorption of O2 and NO2 molecules, which can be further modulated by the external electric field and the in-plane strain. Our calculations predict an effective method to modulate the electronic and optical properties of the b-PC, which may widen its applications in the future electronics and optoelectronics.

p-type ZnSe nanoribbon and n-type Si nanowire are used to prepare crossed p-n nano-heterojuncion through a two step of contact sliding transfer method. Obvious diode characteristics with a large rectification ratio of ~ 20 and a small ideality factor of ~ 2.1 are presented due to the nano-heterojunction's half-surrounded structure and the appropriate energy band alignment between the two materials. Kelvin probe force microscopy measurement and temperature-dependent electrical characterization are devoted to demonstrate the energy barrier and investigate the transport mechanism of the nano-heterojunction. Moreover, under AM 1.5G light illumination, the crossed nano-heterojunction exhibits evident photovoltaic behavior, yielding a power conversion efficiency of ~3%. Our results demonstrate the great potential of the prepared crossed nano-heterojunction in high-performance nano-device applications.

Inspired from the geological processes, this study develops an innovative low-concentration-ratio H2 reduction method to reduce the stoichiometric Au-CuS nanoparticles to produce completely reduced stoichiometric Cu2S with“invisible” Au achieved for single-atom enhancement. A stable Au-Cu1.97S/Cu2S micro/nano-composite is then formed by spontaneous oxidation. From this composite, in combination with the biomimetic technology, an omnidirectional photoabsorption and thermoregulated Au-Cu1.97S/Cu2S-C-T_FW film is designed and fabricated as a novel photothermal-assisted and temperature-autoregulated photodetector for broadband and low-angle-dependent photodetection that exhibits excellent performance with high responsivity (26.37 mA/W), detectivity (1.25×108 Jones) and good stability, which makes it very competitive among current high-performance photodetectors with effective areas within a square-millimeter scale. Au single-atoms exhibit significantly enhanced photodetection (1000 times). This study offers a new concept for improving the stability and the photoelectric properties of copper chalcogenides. Moreover, it opens up a new avenue towards enhancing the performance of optoelectronic and photovoltaic devices using single metal atoms and thermal-assisted, anti-overheating temperature-autoregulation.

Metal oxide gas sensors with porous structures are widely used in numerous applications ranging from health monitoring and medical detection to safety; in this study, we report a highly sensitive SnO

Due to the unique optical and electrochemical properties, large surface area, tunable properties, and high thermal stability, nanoporous anodic aluminum oxide (AAO) has become one of the most popular materials with a large potential to develop emerging applications in numerous areas, including biosensors, desalination, high-risk pollutants detection, capacitors, solar cell devices, photonic crystals, template-assisted fabrication of nanostructures, and so on. This review covers the mechanism of AAO formation, manufacturing technology, the relationship between the properties of AAO and fabrication conditions, and applications of AAO. Properties of AAO, like pore diameter, interpore distance, wall thickness, and anodized aluminum layer thickness, can be fully controlled by fabrication conditions, including electrolyte, applied voltage, anodizing and widening time. Generally speaking, the pore diameter of AAO will affect its specific application to a large extent. Moreover, manufacturing technology like one/two/multi step anodization, nanoimprint lithography anodization, and pulse/cyclic anodization also have a major impact on overall array arrangement. The review aims to provide a perspective overview of the relationship between applications and their corresponding AAO pore sizes, systematically. And the review also focuses on the strategies by which the structures and functions of AAO can be utilized.

Transition metal (TM) and nitrogen co-doped carbon (T M-N -C) materials have emerged as the promising single-atom catalyst (SAC) for the electrocatalytic CO2 reduction reaction (CO2RR), for which the coordination environment of the anchored single atom plays an important role. Inspired by this, the C3N monolayers embedded with the TM single atoms at the C C double vacancy, denoted as M-CC (M Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Mo, Ru, Rh, Pd, Ag, Os, Ir, Pt, and Au), have been evaluated for CO2RR by using the first-principles calculation. We find that the M-CC SACs are of high stability and metallic conductivity, beneficial for the electron transport during the electrocatalytic process. More importantly, all M-CC have high selectivity toward CO2RR versus the hydrogen evolution reaction. Especially, Cu-, Co-, Fe-, and Mn-CC have acceptable or ultra-low limiting potentials of −0.68, −0.48, −0.83, and −0.24 V to produce HCOOH, CH2O, CH3OH, and CH4, respectively. The catalytic activities of M-CC are correlated with the adsorption strength of the key intermediates, further rationalized by the bonding/antibonding population analysis. Our work proposes a new material platform to realize TM-C-N SACs for efficiently electrocatalytic CO2RR, which could provide useful insights into the design of such catalysts.

High broadband absorption with low angular dependence is one of the key factors for photoelectronic applications. Photo-heating accelerating carrier transfer, inducing a change in electrical conductance and exciting “hot” electrons promotes a photoelectric response and extends the response photon energies well below the semiconductor band edge. A photodetector requires cooling to prevent overheating and reduce thermal noise, thereby improving photoelectric detection. Here, these distinct, independent functions, especially the conflicting functions between photo-heating and cooling, are combined into the same structure for the first time. We present an innovative approach using a layered MoS2/nonlayered CdS/Au hybrid heterostructure integrated into a bioinspired sophisticated micro/nanoarchitecture with omnidirectional light-harvesting, effective photothermal conversion and temperature auto-regulation nature to design a self-powered room-temperature photodetector for low angle-dependence and photothermal-assisted broadband photoelectric detection without active cooling. In nearly active areas with a square micron scale, our photodetector attains a responsivity up to 132.06, 122.46 and 74.44 mA/W under an illumination of 660, 808 and 980 nm, respectively, operated under a low bias (0.5 V), which shows a significant advantage over the reported high-performance MoS2 heterostructure photodetectors. Our work shows the concept that photo-heating can be used to enhance photoelectric detection by passive radiative balance. Thus, this work offers a new way to design a novel broadband room-temperature optoelectronic detector that outperforms conventional photodetectors, enabling new technological capabilities.

In order to reduce the thermodynamic stability and improve the dehydrogenation kinetics of Mg hydride, a certain quantity of Nd was introduced into Mg90Al10 alloy to prepare the NdxMg90-xAl10 (x = 2, 5, 8 and 10) alloys. The phase composition and distribution of the alloys identified by X-ray diffraction and scanning electron microscopy showed that there generated hydrogenation phases of Mg(Nd), Mg12Nd and Mg3Nd with increasing Nd content, which formed MgH2 and NdH3 phases during the hydrogenation through disproportionation reactions. The crystalline structure characterized by transmission electron microscopy showed that the grain size of the alloys decreases gradually with increasing Nd content after repeated hydrogenation cycles. The changes of phase composition and microstructure have significant improvement effect on the activation performance and dehydrogenation kinetics. However, Mg hydride in the alloys exhibited different thermodynamic stability. The dehydrogenation enthalpy (ΔHde) was 74.44, 82.59, 74.58 and 73.72 kJ/mol H2 for the NdxMg90-xAl10 (x = 2, 5, 8 and 10) alloys, respectively. Mechanism analysis showed that the existence of Mg(Nd) phase was the root cause of the increase of ΔHde for the Nd-5 alloy. For the Nd-8 and Nd-10 alloys, the formed Nd2H5 phase lowered the thermodynamic stability of MgH2 through causing the lattice deformation of Mg phase.

A macro centimeter-scale Au–CuS combination nanoparticle system integrated with a sub-micrometer antireflection quasi-photonic structure (SAPS) was synthesized for the first time by utilizing T. helena forewings (T_FW) as a biomimetic template (Au–CuS_T_FW). As-fabricated Au–CuS_T_FW exhibits enhanced broadband infrared absorption and lowered reflectance performance. Such an improvement is attributed to the plasmon-to-exciton/plasmon coupling effect among the Au and CuS nanoparticles as well as the coherent coupling between adjacent resonant systems integrated with the SAPS of the T_FW. Moreover, the Au–CuS_T_FW not only possesses a predominant infrared photothermal conversion performance (30.56%), but also is effective for solar photothermal conversion, for low-temperature applications ( T

In this work, Au-Bi(2)Te(3) nanocomposite thermoelectric film with a hierarchical sub-micron antireflection quasi-periodic structure was synthesized via a low-temperature chemical route using Troides helena (Linnaeus) forewing (T_FW) as the biomimetic template. This method combines chemosynthesis with biomimetic techniques, without the requirement of expensive equipment and energy intensive processes. The microstructure and the morphology of the Au-Bi(2)Te(3) nanocomposite thermoelectric film was analyzed by X-ray diffraction (XRD), field-emission scanning-electron microscopy (FESEM), and transmission electron microscopy (TEM). Coupled the plasmon resonances of the Au nanoparticles with the hierarchical sub-micron antireflection quasi-periodic structure, the Au-Bi(2)Te(3) nanocomposite thermoelectric film possesses an effective infrared absorption and infrared photothermal conversion performance. Based on the finite difference time domain method and the Joule effect, the heat generation and the heat source density distribution of the Au-Bi(2)Te(3) nanocomposite thermoelectric film were studied. The heterogeneity of heat source density distribution of the Au-Bi(2)Te(3) nanocomposite thermoelectric film opens up a novel promising technique for generating thermoelectric power under illumination.

In this study we investigate the collective behavior of the generalized Kuramoto model with an external pinning force in which oscillators with positive and negative coupling strengths are conformists and contrarians, respectively. We focus on a situation in which the natural frequencies of the oscillators follow a uniform probability density. By numerically simulating the model, it is shown that the model supports multistable synchronized states such as a traveling wave state, π state and periodic synchronous state: an oscillating π state. The oscillating π state may be characterized by the phase distribution oscillating in a confined region and the phase difference between conformists and contrarians oscillating around π periodically. In addition, we present the parameter space of the oscillating π state and traveling wave state of the model.

In this study, the carbon-matrix Ag wing with a hierarchical sub-micron antireflection quasi-photonic crystal structure (HSAS) was fabricated by a simple and promising method. This method combines chemosynthesis with biomimetic techniques, without the requirement of expensive equipment and energy intensive processes. Here, the Troides helena (Linnaeus) (T. helena) forewing (T_FW) was chosen as the biomimetic template. The carbon-matrix Ag butterfly wing (Ag@C_T_FW) achieves a drastically enhanced infrared absorption over a broad spectral range, especially, over the near infrared region. Here, we report methods to enhance and modify the plasmonic resonances in such structures by strongly coupling plasmonic resonances to HSAS. Using the finite difference time domain (FDTD) method, the absorption spectra and the distribution of the energy density near the Ag NPs surface were simulated. Based on the experiment and simulation results, these findings demonstrate that the enhanced infrared absorption over a broad spectral range is due to the mechanism that the plasmon and the coherent coupling between adjacent resonance systems integrate with the HSAS.

The drift of the isospin degree of freedom (IDOF) is experimentally visualized through the wide-range angular distribution and the beam energy dependence of the isospin composition of light charged particles (LCP) produced in heavy ion collisions. It is evidenced that the net isospin transport is presented in the whole process from early dynamic emission to the statistical evaporation lasting to very late stage. Due to the long-time accumulation of the isospin effect, the angular distribution of the relative neutron excess summing over the LCPs is utilized as a sensitive probe to the symmetry energy. With S fixed at 28.3 MeV, a soft density dependence with L=33–61 MeV (0.95 confidential level) at ρ0 is circumstantially deduced using an improved quantum molecular dynamics transport model attached with a statistical emission afterburner.

The hybrid coating was synthesized on titanium by sol-gel process. Three-point flexure test was used to investigate the adhesion between porcelain–Ti. The structure and micromorphology of titanium specimens were tested by X-ray diffraction and scanning electron microscopy. With decreasing the silicon content, the gel time and stability of the sol increased accordingly, indicating the increased stability of the sol. A coherent coating with SnO nanoparticles was deposited on titanium. The porcelain–Ti bonding strength and corrosion resistance were enhanced by the hybrid coating. The porcelain–Ti bonding strength maintained constant during immersion in neutral saliva and neutral saliva containing fluorine ion, respectively. However, bonding strength decreased from 49 to 35 MPa after immersion in acidic saliva containing fluorine ion of 100 ppm.

We propose a method for extracting the properties of the isobaric mass parabola based on the total double -decay energies of isobaric nuclei. Two important parameters of the mass parabola, the location of the most -stable nuclei and the curvature parameter , are obtained for 251 A values, based on the total double -decay energies of nuclei compiled in the AME2016 database. The advantage of this approach is that the pairing energy term caused by the odd-even variation can be removed in the process, as well as the mass excess of the most stable nuclide for the mass number A, which are employed in the mass parabolic fitting method. The Coulomb energy coefficient MeV is determined by the mass difference relation for mirror nuclei, and the symmetry energy coefficient is also studied by the relation .

Coupling of optics, thermodynamics and thermal radiation principle, this work simulated the photoinduced heat generation and thermal radiation arisen in plasmonic structures. The results showed that the thermal radiation properties can be regulated effectively, by tuning the morphology and structure parameters of plasmonic structures, or via combining these plasmonic structures reasonably. Furthermore, the thermal radiations in plasmonic structures were mapped by numerical approaches. The thermal radiation maps evidenced that the structure with small radius of curvature enhances the electromagnetic-field concentration which promotes heat generation and enhances thermal radiation. Additionally, we visually revealed that the adjacent coupling enhances the thermal emission.

Templated from the bristles on Papilio maacki wings, single porous SnO2 microtubes (SPSMs) have been synthesized by soaking and sintering. The delicate microstructure and morphology of SPSMs were characterized by SEM and TEM. Silver electrodes were precisely contacted on the two ends of an SPSM for gas-sensing measurement in reducing gases. The SPSMs were highly sensitive to trace ammonia, formaldehyde, and ethanol at room temperature. They also exhibited low working temperature and short response/recovery times. The average response and recovery times were only about 3 s and 30 s. Compared with the non-porous structure and the filled structure, the SPSMs showed higher sensitivity. The fascinating biomorphic structure of the SPSMs will open a new way for the design and application of sensor devices for the detection of harmful and toxic gases.

The effects of anodization processes on titanium-porcelain bonding were investigated. The morphologies and phase structures were evaluated by field-emission scanning electron microscopy (F-SEM) and X-ray diffraction (XRD). The bonding strength was investigated by three-point flexure test. The corrosion resistance of titanium in artificial saliva was investigated. The SEM results showed that a titanium oxide film with submicron stripes and nano-pores could be prepared by anodization and HF acid pretreatment. This titanium oxide film increased chemical bonding and mechanical interlocking between titanium and porcelain. The anodization process also enhanced the corrosion resistance of the titanium, which led to the increase of corrosion durability of the Ti-porcelain bonding strength.

Dynamical nuclear shell effect is introduced to the improved quantum molecular dynamics model in interaction potential energy in the process of fusion reactions. The dynamical shell correction energy of the system is calculated and applied to dynamical process of fusion reactions with a switch function employed to connect the shell correction energy of the projectile and target with that of the compound nucleus. It is found that the shell effect enhances the fusion barrier and the calculated fusion (capture) cross-sections decrease for subbarrier fusion reactions which both projectile and target are doubly magic nuclei. The experimental data of the fusion cross-sections for four systems 40 Ca + 48 Ca , 48 Ca + 48 Ca , 16 O + 208 Pb and 48 Ca + 208 Pb can be reproduced better with the shell effect being considered by using the ImQMD model.

We theoretically investigate the influence of external magnetic fields on current oscillations in weakly coupled GaAs / Al x Ga 1-x As superlattices when the system is driven by a pure DC voltage. The formation of unstable electric-field domains under the action of a small magnetic field indicates the current oscillation occurs in superlattices. Increasing magnetic fields, the stationary electric-field domain is created and current oscillations disappear. Thus, the system state is transferred from dynamic to stationary by the control of magnetic fields. When the system is subject to an AC voltage in the presence of small magnetic fields, a variety of nonlinear behaviors are obtained due to the coupling between the internal oscillations and external signals.

First-principles calculations have been carried out to investigate the possibility of B-, N-, Si-, and S-doped black phosphorus carbide monolayers (B-, N-, Si-, and S-bPCs) as efficient gas sensors to detect and eliminate toxic gas molecules such as NO2 and NH3. The influence of O2 and H2O has also been considered. It is found that O2, H2O, NO2, and NH3 are all physisorbed on N- and S-bPCs. Nevertheless, the moderate adsorption energy and large charge transfer of NO2 on N-bPC indicate that N-bPC is more suitable to detect NO2. The chemisorption is observed when NO2 and NH3 are adsorbed on B-bPC, and O2, NO2, and NH3 on Si-bPC, by which highly enhanced sensitivity toward these molecules can be realized. Due to the strong adsorption, B- and Si-bPCs can be used to detect and filter NO2 and NH3 at different working temperatures. The work function has been calculated to further interpret the adsorption mechanism. It increases with B and Si dopants and decreases with N and S dopants. The adsorption of molecules leads to different variations of the work function, which is correlated with the direction of charge transfer. Our theoretical investigations help us better understand the mechanism of bPC as a NO2 and NH3 gas sensor and provide a facile method to broaden its application in industrial, medical, and environmental monitoring.

Angular distributions of fragments have been studied for 197 Au +197 Au ternary reactions at bombarding energy 15 A MeV by an improved quantum molecular dynamics model. The calculated results are qualitatively in agreement with the experimental data. Through analyzing the angular distributions of fragments, it is shown that in semi-peripheral collisions 197 Au +197 Au interacting system often reseparates into three massive fragments which are almost aligned in space along the separation axis. The anisotropic distribution in azimuthal angle ϕ shows that the projectile-like fragment (PLF) or target-like fragment (TLF) breaks up violently, reflecting nonequilibrium effects in the consecutive reseparation. The time scale elapsing from the scission of the binary PLF+TLF system to the secondary scission of PLF or TLF is estimated to be of about 80 fm /c. It is found that the distribution in Θ cm depends on the impact parameter, and its peak seems to be moving and narrowing with increasing impact parameter. Its asymptotic peak value is in agreement with the grazing angle. The shift of the peak value of Θ cm implies that the collective energy dissipation depends on impact parameter and decreases with impact parameter increasing since the exchange of nucleons becomes less frequent during the reaction process.