Visible-light-activated metal oxide semiconductor (MOS) gas sensors have great potential for room-temperature gas detection, but their performance is often limited by insufficient light absorption and rapid charge carrier recombination. In this work, we present a hierarchical heterostructure design that integrates one-dimensional (1D) In2O3 nanofibers integrated with two-dimensional (2D) In2S3 nanosheets to enhance NO2 detection performance. The combination of wide-bandgap 1D In2O3 and narrow-bandgap 2D In2S3 not only extends the visible-light absorption range but also effectively suppresses the recombination of photogenerated carriers, thereby enabling efficient charge separation. This synergistic effect enhances the surface density of photo-generated charge, which is crucial for improving NO2 adsorption and detection performance. The optimized sensor demonstrates excellent room-temperature NO2 sensing performance under visible-light illumination, achieving a high response (Rg/Ra = 6.5) to 1 ppm NO2, a 4.6-fold improvement compared to pure In2O3 nanofibers. Additionally, the sensor exhibits a low detection limit of 50 ppb and outstanding long-term stability. Density functional theory (DFT) calculations revealed that the adsorption energy for NO2 molecules at the heterointerface is-2.09 eV, which is higher than that at the individual components. Furthermore, in-situ gas-phase NO2 concentration monitoring confirmed that the hierarchical heterostructures significantly enhance NO2 adsorption under visible light illumination, a finding further corroborated by the data obtained from the temperature-programmed desorption (TPD) analyzer. This work presents an innovative strategy for designing MOS-based heterostructures, providing a promising platform for high-performance visible-light-activated gas sensors.

Photochromic flexible materials have demonstrated broad applications in wearable devices due to their conformability, fast photo-response, and long cycling lifetime. However, single-component organic or inorganic systems often face challenges in balancing flexibility with reversible cycling stability. Herein, BaMgSiO4:Eu2 + (BMS:Eu) and BaMgSiO4:Eu2+/Fe3+ (BMS:Eu/Fe)-based photochromic flexible films were fabricated by embedding inorganic powders into thermoplastic polyurethane (TPU) via electrospinning technique. Under 365 nm irradiation, the BMS:Eu/Fe system exhibits superior photochromic performance (Delta R = 37.78 %), whereas the BMS:Eu system shows higher photoluminescence modulation capability (Delta Ri = 25.63 %). Both systems achieve their maximum optical response within 5 s and maintain stable performance over 10 cycles. This work realizes a dual-mode photochromic-photoluminescent response and visual regulation under 365 nm excitation, showing potential applications in wearable technology and smart clothing.

X-ray optical imaging, an essential analytical technique for visualizing internal structures, has gained substantial research attention. However, its primary challenge involves establishing safe, non-destructive signal readout strategies. This study introduces an Er/Yb co-doped Li0.4Na0.6NbO3 phosphor that facilitates information writing through X-ray-induced photochromism (PC) and creating non-destructive readout via 980 nm laser-excited upconversion luminescence (UCL), enabling a safe, tunable dual-mode X-ray writing/NIR laser nondestructive readout imaging system. Experimental results reveal remarkable photochromic responsiveness (Delta R1 = 54.26%) under X-ray irradiation and accurate UCL intensity modulation (Delta Rt= 93.84%) via the photochromic effect, achieving novel dual-mode three-dimensional imaging application. This research offers valuable design guidelines for novel, safe, and tunable optical imaging materials.

The semimetal characteristic of graphene seriously obstructs its extensive application as a heat-dissipation material in electronic devices. Therefore, it should be urgent to design semiconducting graphene-based structures of high thermal conductivity (TC). In this paper, we construct the hybrid structures composed of graphene and other carbon-based monolayers such as BC 3 , C 3 N, and BC 6 N. It is shown that the hybrid structures may be kept to be semiconducting while their TCs will be increased with the increasing of the graphene zone width. By comparing the TCs of the hybrid structures affiliated with the side comb-type and plane-type structures, we find that the side plane-type structures can enhance the TCs more strongly than the comb-type ones. A further study on the isotope doping shows that the isotope doping in the side structures may induce the increasing of TC. This research provides an important reference for designing the semiconducting and high-TC graphene-based hybrid materials.

The development of miniaturized and lightweight supercapacitors (SCs) becomes a hot research region. Improving the surface area utilization of porous carbon materials can effectively promote the energy density and power density of SCs. This work first constructs three-dimensional porous poly(p-phenylenediamine) hydrogel through adding phytic acid. Thereafter, N, O, P-doped porous carbon (NOPPC) was obtained via simple one-step pyrolysis treatment. The unique three-dimensional porous structure of NOPPC inherited from poly(p-phenyl-enediamine) hydrogel provides plentiful ion storage space and ion transportation channels. Heteroatom-doped feature endows NOPPC with good wettability and more active surface area. The surface utilization of NOPPC-800 reaches up to 2.56 F m- 2, which is better than many carbon materials in literatures. NOPPC-800 can still maintain 135 F g-1 at 20 A g-1. The capacity retention ratio of NOPPC-800 can reach up to 93.4 % after 10000 cycles at 10 A g-1. The quantitative analysis of energy storage mechanism of NOPPC illustrates the synergistic impact of pore structure and doped heteroatoms. These electrochemical results show that NOPPC possesses good practical application value. NOPPC-800//NOPPC-800 supercapacitor shows high energy density and excellent cycle stability. The results show that the balance of heteroatom content, specific surface area and conductivity is the key to obtain promising carbon electrode materials and can be realized via tuning carbonization temperature. This work also demonstrates that rational structure control of carbon precursor is the effective way to promote the capacity of carbon materials.

通过二步水热法合成了同时具备优异还原性和氧化性的复合光催化剂Bi2WO6/SrTiO3.研究了在可见光下Bi2WO6/SrTiO3复合样品对Cr(Ⅵ)的还原反应和对亚甲基蓝的氧化反应.复合催化剂20 min可以将5 mg/L的Cr(Ⅵ)几乎完全还原,将20 mg/L的亚甲基蓝完全氧化.Bi2WO6和SrTiO3半导体匹配的禁带结构有效地削弱空穴和电子对的复合.光催化还原Cr(Ⅵ)的活性物质为光生电子,光催化氧化亚甲基蓝的活性物质为OH·和光生空穴.

Piezoceramics with high piezoelectric performance in a wide elevated temperature range are the best potential stocks used in advanced high-temperature piezoelectric devices. Here, novel ternary perovskite piezoceramics of (0.997-x)BiScO3-xPbTiO3-0.003Bi(Zn2/3Nb1/3)O3 (BS-xPT-BZN) are synthesized and investigated. The morphotropic phase boundary (MPB) composition of the BS-xPT-BZN system is located at x = 0.625, which exhibits a high Curie temperature (TC) of 442 degrees C. More excitingly, the in-situ piezoelectric coefficient (d33) of the x = 0.625 MPB sample is not only as high as 558 pC/N at 200 degrees C, but also has a fluctuation rate of less than & PLUSMN; 10 % in the ultra-wide high-temperature range of 100 - 308 degrees C. The above excellent comprehensive high-temperature piezoelectric performance should be attributed to the synergistic effect of composition-related MPB and dispersion characteristics and thermally stable ferroelectric domain state. The results demonstrate that BS-xPTBZN ceramics can be used as very competitive perovskite piezoelectrics to construct piezoelectric devices for applications in harsh high-temperature environments.

Because of the difficulty in measuring the cluster isotope displacement and identifying its cause, the resonance dissociation spectra, the moment shift and Zeeman energy shift of isotope cluster 87,85Rbn (n = 1, 2, 3, ··· , 13) are obtained by the combination of optical magnetic resonance and thermal dissociation techniques in this study. The quantitative calculation is carried out based on the conceptual model of the giant atom, and the results are in excellent agreement with the measured results, which shows that rubidium clusters can be analyzed as giant atoms. Furthermore, 5s electron shell level structures of the rubidium cluster 87,85Rbn (n = 1, 2, 3, ··· , 92) are calculated by using Zeeman level interval model. It is found that the main order and step distance of the 5s electron shell structure are similar to those of 3s single electron shell structure of sodium cluster in spherical symmetry. It is confirmed that the structure of the 5s electron shell of the rubidium cluster is determined by the largest energy gap in total Zeeman levels and the characteristic peaks of odd and even alternating and anomalous magnetic moments of special numbers such as n = 2 are caused by the intrinsic properties of electrons and molecular structures. It is also found that 87Rbn level shell structure and 85Rbn level shell structure strictly conform to the ratio of 3/2 magnitude relationship, and that there are abnormal differences in spectral center frequency and broadening, which may be directly related to the 85,87Rb nuclei close to the shell closure.

The dipole species transformation and polarization relaxation configuration are achieved by changing the cobalt ion stoichiometry,which precisely tailors the electromagnetic attenuation performance of bismuth iron cobalt oxide.When the stoichiometric ratio of Fe:Co is 19:1,the optimal reflection loss reaches-60 dB.The high electromagnetic attenuation performance significantly improve the linear sensitivity of the strain response and active customized stealth capability of the designed multifunctional capacitor-like structure.Therefore,the wireless multifunctional design integrates energy attenuaten of electromagnetic wave with the wireless sensing and active camouflage functions for the first time.The work provides an important step for the realization of electromagnetical multifunctional applications including electromag-netic protection and electromagnetic sensing in artificial beings,medical health and even space travel.

Large high-temperature d 33 and high T d are simultaneously realized in new BS–BY–PT ceramics for piezoelectric energy harvesting.

热力学统计物理是一门师范类物理学专业的重要理论课程,为了培养师范生的学科素养,从而帮助学生在毕业走上教学岗位后,成为一名合格的中学物理教师,本文对热力学统计物理教学过程中遇到的问题进行思考,并提出改进方案,希望能够提高教学效果,扎实物理师范生的学科素养.

Simultaneously achieving large piezoelectricity and excellent thermal stability in a piezoceramic is highly desired for constructing advanced high-temperature electromechanical coupling devices. Here, a large hightemperature piezoelectric coefficient (d33 = 523 pC/N at 200 degrees C) with a small fluctuation rate (eta <= +/- 10 %) over an ultra-broaden temperature range of 48-342 degrees C was achieved in novel zBiScO3-xBiInO3-yPbTiO3 (zBS-xBIyPT) ternary perovskite piezoceramics with a high Curie temperature of 440 degrees C. The morphotropic phase boundary (MPB) of multiphase coexistence can be driven and optimized in this system, which is mainly responsible for the enhanced piezoelectricity, and the optimal MPB composition is located at x/y/z = 0.010/ 0.625/0.365. The excellent temperature stability of the optimal MPB sample should be attributed to the increase in the number of thermally stable irreversible non-180 degrees domains. zBS-xBI-yPT perovskite ceramics with excellent comprehensive high-temperature piezoelectric properties exceed many reported lead-based counterparts, and are more suitable for electromechanical coupling applications at harsh elevated temperatures.

Advanced high-temperature piezoceramic energy harvesters (HT-PEHs) highly rely on perovskite ceramics with large high-temperature piezoelectricity. However, it remains a great challenge to achieve high piezoelectric coefficient (d33) at elevated temperatures, which severely limits the development of piezoelectric materials in cutting-edge energy harvesting applications. Here, yBiScO3-xPbTiO3-0.05Pb(Zn1/3Nb2/3)O3 (yBS-xPT-PZN) ternary perovskite piezoceramics are prepared, in which the morphotropic phase boundary (MPB) composition (x/y = 0.60/0.35) exhibits a large d33 of 655 pC/N at 300 degrees C, outperforming many reported other perovskite piezoceramics. The excellent high-temperature piezoelectricity should benefit from the lattice softening effect and the stable ferroelectric domain state associated with the high tetragonal phase content. In addition, the HT-PEH assembled from the MPB sample exhibits good power generation performance (e.g., a giant power density of 418 mu W/cm3) at 300 degrees C, and can charge a 10 mu F commercial capacitor to 7 V within 40 s. Such a large piezo-electric coefficient and power density of yBS-xPT-PZN system at a high temperature of 300 degrees C is a promising candidate for fabricating high-performance HT-PEHs to meet the urgent requirements of advanced high -temperature energy harvesting applications.

Sodium ion battery is a new energy star to meet carbon neutrality idea due to abundant resources and low price. The exploration of proper anode materials to accommodate Na+ is a significant research subject. Here, N/O dual -doped carbon spheres (NOCS) derived from polyaniline have been easily prepared via pyrolysis treatment of polyaniline spheres (PS). When applied as an anode material for SIBs, NOCS shows the superior capacity (314 mAh g(-1) at 50 mA g(-1)), good rate performance (139 mAh g(-1) at 2 A g(-1)) and excellent structural stability. The great electrochemical capacity of NOCS can be attributed to the unique spherical structure, large carbon inter -layer distance (0.375 nm), proper specific surface area (211 m2 g(-1)) and abundant heteroatom content (6.27 at% of nitrogen and 14.88 at% of oxygen). NOCS also displays excellent capacitance (104.4 F g(-1) at 20 A g(-1)) and long cycling life (145.4 F g(-1) at 1 A g(-1) after 5000 cycles) as an electrode material for supercapacitors. These results illustrate that designing structure and composition will effectively promote the electrochemical properties of carbon materials.

Molecular dynamics simulations are conducted to study the effect of Re and Co addition in the Ni-based single-crystal superalloys on its flow stresses under varying temperature. It is found that Re and Co increase the flow stresses of the superalloys at 100, 300 and 500 K, respectively. The solid solution strengthening mechanism is enhanced with the addition of Re or Co atoms. Moreover, Re or Co promote dislocation nucleation and multiplication and, thus, increase the dislocation density which increases the possibility of forest dislocation interactions. The dislocation proliferation increases additional work hardening capability of the superalloy. At atomic scale, the 1/6<110> stair-rod dislocations were increased by more than 33% (or 11%) for the 2 at.% Re (or Co) systems. Due to the sessile nature of stair-rod dislocation, Re or Co will undeniably affect the mechanic properties of superalloy involving the dislocation mechanisms. For similar concentration of additions, Re is more effective in strengthening the single-crystal superalloys compared with the addition of Co.

Molecular dynamic analysis was performed on pure and doped (by Re, Ru, Co or W) Ni at 300 K using the embedded-atom-method (EAM) potentials to understand the crack formation of the doped Ni matrix in the (010)[001] orientation. When Ni was doped with Re, Ru, and W, the matrix demonstrated increased lattice trapping limits and, as a result, improved the mechanical properties. Consequently, this prevented the bond breakage at the crack tips and promoted crack healing. The average atomic and surface energy values increased when Re, Ru, and W were added. Analysis of these energy increase helpedus to understand the influence these elements had on the lattice trapping limits. The fracture strength of the Ni matrixat 300 K increased because of the formation of the stronger Ni–Re, Ni–Ru, and Ni–W bonds. At the same time, doping the Ni matrix with Co did not demonstrate any strengthening effects because of the formation of Co–Ni bonds, which are weaker than the Ni–Ni bonds. Out of all dopants tested in this work, Ni doping with W showed the best results.

For the magnetism of alkali metal clusters, it is difficult to determine the number of atoms and the magnetic moment of isolated atoms cluster. In this paper, we investigate the magnetic moment of single atomic molecule 87Rb1 and 14 kinds of cluster particles (87Rb)\begin{document}${}_{n'} $\end{document} (\begin{document}$n' $\end{document}= 2, 3, 4, ···, 15) in a saturated rubidium vapor sample at about 328 K, by using optical magnetic resonance spectroscopy. The experimental results show that there is a relationship f\begin{document}${}_{n'} $\end{document} = f */\begin{document}$n' $\end{document} between the resonant frequencies f\begin{document}${}_{n'} $\end{document} of 14 kinds of cluster particles (87Rb)\begin{document}${}_{n'} $\end{document} and the resonant frequencies f * of 87Rb1. The magnetic moment and their resonance amplitudes show two different relationships with the \begin{document}${n'} $\end{document} odevity. When the particles have an odd number of 5s electrons, they must have spontaneous magnetic moment, and the value of magnetic moment increases with n and decreases inverse proportionally with the combined angular momentum F of the cluster particles. The amplitude obtained from resonance spectrum complies with the variation law of magnetic moment value. On the other hand, for the cluster particles with n being even number, the magnetic moment value becomes 0 and the amplitude is also 0 in the most cases, except for the cluster particles 87Rb2 with n = 2 i.e. two 5s electrons, which is caused by the Jahn-Teller effect of the linear molecules, and the magnetic moment value is consistent with the calculation results of the odd number particles. When n > 2, the coupling effect between the magnetic moments of the Rb cluster shows a long-range ordered antiferromagnetic property with the increase of the number of 5s valence electrons n. The electron configuration and molecular state of the ground state and the lowest excited state of 14 kinds of 2—15 atoms cluster particles 87Rbn, as well as the stability of each molecular state and the possibility of visible Zeeman effect are obtained by using the molecular orbital-state theory analysis and constructing the 87Rbn–1 + 87Rbn atomic cluster model. Furthermore, based on the magnetic moment of diatomic molecules ruler, it is found that when n = \begin{document}${n'} $\end{document}, the magnetic moment of (87Rb)\begin{document}${}_{n'} $\end{document} and 87Rbn are in strict consistency (the average relative error is only 0.6765%), confirming the corresponding relationship between (87Rb)\begin{document}${}_{n'} $\end{document} and 87Rbn. This research will be of great value in the magnetic research of cluster particles.

The mechanisms underpinning high energy storage density in lead-free Ag1-3xNdxTayNb1-yO3 antiferroelectric (AFE) ceramics have been investigated. Rietveld refinements of in-situ synchrotron X-ray data reveal that the structure remains quadrupled and orthorhombic under electric field (E) but adopts a non-centrosymmetric space group, Pmc21, in which the cations exhibit a ferrielectric configuration. Nd and Ta doping both stabilize the AFE structure, thereby increasing the AFE-ferrielectric switching field from 150 to 350 kV cm(-1). Domain size and correlation length of AFE/ferrielectric coupling reduce with Nd doping, leading to slimmer hysteresis loops. The maximum polarization (P-max) is optimized through A-site aliovalent doping which also decreases electrical conductivity, permitting the application of a larger E. These effects combine to enhance energy storage density to give W-rec = 6.5 J cm(-3) for Ag0.97Nd0.01Ta0.20Nb0.80O3.

借鉴国内外的教学经验,从数学物理方法课程教学理念的更新、课程教学内容体系的调整、课程教学手段的改变和课程成绩评价方法的变更这四个方面,介绍了本课题组的教学改革探索,以提升"互联网+"时代背景下的应用型人才的培养质量.