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A novel wearable pressure sensor produced by introducing temperature-stimulated epoxy into the carbonized melamine foam/silicone system has an ultra-wide detection range with the aid of temperature or voltage.

The incorporation of Sc3+ can stabilize calcite-phase LuBO3:Ce3+ to grow large-sized single crystals but leads to the significant degradation of scintillation performance.

The application of LuBO3:Ce3+ (LBO:Ce) crystal as an excellent scintillation material has been limited due to its poor phase stability at high temperature or high pressure, so improving the phase stability is essential for promoting its development. Ga stabilized LuBO3:Ce3+ (LGBO:Ce) is synthesized by solid-state reaction at 1200 °C. Powder X-ray diffraction patterns and Raman spectra at ambient pressure show that all the samples are pure calcite phase. In situ high-pressure synchrotron radiation XRD patterns illustrate that calcite phase LGBO:Ce exhibits more excellent phase stability than that of LBO:Ce under high pressure due to the superior compressibility of the [GaO6] octahedral unit. The optical band gap of LGBO decreases from 5.58 to 4.64 eV after introducing 10% Ga, which leads to the decreased nonradiative transition and about double luminescence intensity as expected. More interestingly, the charge transition from O2- to Ce4+ is observed at about 290 nm in the absorption spectra. The X-ray photoelectron spectroscopy spectra indicate the ratio of Ce4+/Ce3+ increases with increasing concentration of Ga3+, which can be attributed to the variation of energy separation between the 4f ground state of Ce3+ and the Fermi energy level position. In contrast to the enhancement of PL intensity, the integrated X-ray excited luminescence intensity decreases after Ga3+ incorporation attributing to the result of both decreased effective atomic number and ionization energy between 5d1 level and conduction band. The thermal luminescence spectra show that after the incorporation of Ga3+ the oxygen vacancy and intrinsic defects in LBO remain unchanged but that the concentration of oxygen vacancy significantly reduces. The mechanism of Ga3+ incorporation on phase stability and luminescence properties of LBO:Ce has been proposed and discussed systematically.

The fatigue life and fatigue stress of 30CrMnSiA material are studied by fracture retro estimation under experimental conditions. With the help of Scanning electron microscopy (SEM), fatigue crack can be observed. By Paris law, the fatigue life and fatigue stress of 30CrMnSiA material can be estimated by fatigue striation under the experimental environment. The method is simple and feasible, and the relative error is lower.

The atomic kinetic Monte Carlo method plays an important role in multi-scale physical simulations because it bridges the micro and macro worlds. However, its accuracy is limited by empirical potentials. We therefore propose herein a triple-encoding algorithm and vacancy-cache mechanism to efficiently integrate ab initio neural network potentials (NNPs) with AKMC and implement them in our TensorKMC codes. We port our program to SW26010-pro and innovate a fast feature operator and a big fusion operator for the NNPs for fully utilizing the powerful heterogeneous computing units of the new-generation Sunway supercomputer. We further optimize memory usage. With these improvements, TensorKMC can simulate up to 54 trillions of atoms and achieve excellent strong and weak scaling performance up to 27,456,000 cores.

The application of LuBO

Perovskite photovoltaics are strong potential candidates to drive low-power off-grid electronics for indoor applications. Compared with rigid devices, flexible perovskite devices can provide a more suitable surface for indoor small electronic devices, enabling them have a broader indoor application prospect. However, the mechanical stability of flexible perovskite photovoltaics is an urgent issue solved. Herein, a kind of 3D crosslinking agent named borax is selected to carry out grain boundary penetration treatment on perovskite film to realize full-dimensional stress release. This strategy improves the mechanical and phase stabilities of perovskite films subjected to external forces or large temperature changes. The fabricated perovskite photovoltaics deliver a champion power conversion efficiency (PCE) of 21.63% under AM 1.5G illumination, which is the highest one to date. The merit of low trap states under weak light makes the devices present a superior indoor PCE of 31.85% under 1062 lux (LED, 2956 K), which is currently the best flexible perovskite indoor photovoltaic device. This work provides a full-dimensional grain boundary stress release strategy for highly stable flexible perovskite indoor photovoltaics.

Vacancy and its clusters are among the most important defects induced by self-irradiation in plutonium-gallium (Pu-Ga) alloys. For decades-long stockpiles, the generation and evolution of vacancy defects could cause void swelling and helium bubble formation, resulting in the ageing of the Pu-Ga alloys. Therefore, to shed light on the ageing mechanisms caused by vacancies in Pu-Ga alloys, the long-term behaviour of vacancy defects in Pu-Ga alloys is simulated employing an AKMC model parameterized by molecular statics calculations. By tracking the number of vacancy defects, the size distribution of vacancy clusters, and the largest vacancy clusters over time, we found that temperature and Ga concentration significantly influence the evolution of vacancy defects in Pu-Ga alloys. Temperature changes could affect the clustering behaviour of mono vacancies, and critical temperatures initializing the nucleation of vacancy clusters are observed. On the other hand, adding Ga contents in Pu-Ga alloys could increase the migration energy of and attractive interaction among vacancies, leading to increased vacancy cluster numbers at high temperatures.

Understanding the evolution of irradiation-induced defects is of critical importance for the performance estimation of nuclear materials under irradiation. Hereby, we systematically investigate the influence of He on the evolution of Frenkel pairs and collision cascades in tungsten (W) via using the object kinetic Monte Carlo (OKMC) method. Our findings suggest that the presence of He has significant effect on the evolution of irradiation-induced defects. On the one hand, the presence of He can facilitate the recombination of vacancies and self-interstitial atoms (SIAs) in W. This can be attributed to the formation of immobile He-SIA complexes, which increases the annihilation probability of vacancies and SIAs. On the other hand, due to the high stability and low mobility of He-vacancy complexes, the growth of large vacancy clusters in W is kinetically suppressed by He addition. Specially, in comparison with the injection of collision cascades and He in sequential way at 1223 K, the average sizes of surviving vacancy clusters in W via simultaneous way are smaller, which is in good agreement with previous experimental observations. These results advocate that the impurity with low concentration has significant effect on the evolution of irradiation-induced defects in materials, and contributes to our understanding of W performance under irradiation.

We investigate the hcp to bcc phase transition in beryllium (Be) at high-pressure and -temperature ($PT$) conditions. A recently developed hybrid approach that combines first-principles molecular dynamics and lattice dynamics is used to account for anharmonic contributions to the free energy. Anharmonic effects are shown to be strong at high $T$ in both hcp and bcc Be. They are stronger in hcp Be than in bcc Be, as evidenced by the larger anharmonic vibrational entropy of hcp Be. We find that anharmonicity has a significant influence on the hcp to bcc transition at high-$PT$ conditions. It substantially enlarges the stability domain of hcp Be at high $T$ compared with that calculated under the quasiharmonic approximation (QHA), as a result bringing theoretical predictions into good consistency with recent experimental observations. After considering anharmonic effects, the calculated pressure and temperature of the hcp/bcc/liquid triple point increase from about 85 to 165 GPa, and from about 3300 to 4200 K, respectively, and the predicted Clapeyron slope at the triple point takes a value of $\ensuremath{-}7.4\ifmmode\pm\else\textpm\fi{}0.7\phantom{\rule{0.28em}{0ex}}\mathrm{K}/\mathrm{GPa}$, noticeably larger in magnitude than previous QHA results in the range of $\ensuremath{-}3$ to 2 K/GPa.

To solve the problem of glue breakage and overflow in the packaging process of mobile phones, a glue detection algorithm based on the depth map is proposed. By collecting the image no gluing and gluing after dispensing, the pixel value of each frame in the corresponding position of the corresponding sample is sequentially intercepted in the same sample, and the glue contour is reconstructed by rearranging the intercepted ROI. Last, measure the width and height information of the glue according to the contour, and judge the defect problem at the same time. Experimental results show that the algorithm can accurately measure the result of the micron-level glue, and accurately determine the lack of glue. At the same time, the measurement accuracy of the algorithm is 0.01mm, and the measurement results are accurate and stable.

The optical filter effect of the metal–dielectric–metal (MDM) waveguide with stub structure is investigated with surface plasmons (SPs) interference theory and simulated using finite difference time domain (FDTD) method. The transmission process of the surface plasmons propagating through the stub structure is discussed in detail, and testified by different time step field intensity images of FDTD simulation. It is verified by the FDTD simulation that the oscillation periods of the transmission curves are proportional to the wavelengths, and the number of the wavelength of the standing wave in the stub is linear to the stub length d. When the monochromatic continuous waves are incident, the transmissions are also periodically changed with the length of the stub. The shorter wavelengths present better filter sensitivity than longer wavelengths. The above optical filter effect implies that the MDM waveguide with stub structure can be applied in the fields of photonic integration devices and sensors.

The phase transition temperatures of CaZrO3-doped (Na0.49K0.49Li0.02)(Nb0.8Ta0.2)O-3 lead-free piezoelectrics (LKNNT-CZ5) have been studied with X-ray diffraction and Raman scattering. It is found that LKNNT-CZ5 ceramics and powders with the same crystallite size (similar to 2-5m) exhibit distinctly different phase transition behaviors versus temperature. The ceramic bulk changes its orthorhombic phase to tetragonal structure abruptly after being pulverized to powders at room temperature(RT), and follows a phase transition sequence with increasing temperature: orthorhombic (RT-65 degrees C), orthorhombic and tetragonal (65 degrees C-105 degrees C), and tetragonal phase (105 degrees C to similar to 220 degrees C). Contrastively, the powders hold a tetragonal structure without any phase transition within the whole temperature region (RT-220 degrees C). These differences might be induced by the existing internal stress or residual strain, which could be released during the grinding process.

Influence of K/Na ratio in (KxNa1-x)NbO3 on the ferroelectric stability and consequent changes in the electrical properties of 0.99(Bi0.5Na0.4K0.1)TiO3-0.01(KxNa1-x)NbO3 (BNKT-KxNN) ceramics were investigated. Results showed that change of K/Na ratio in KNN induces a phase transition from ferroelectric to ergodic relaxor phase with a significant disruption of the long-range ferroelectric order, and correspondingly adjusts the ferroelectric-relaxor transition point TF-R to room temperature. Accordingly, giant strain of 0.46% (corresponding to a large signal d(33)* of 575pm/V) which is comparable to that of Pb-based antiferroelectrics is obtained at a K/Na ratio of 1, and the emergence of large strain response induced by the change of K/Na ratio of KNN can be well explained by the correlation between the position of ferroelectric-ergodic relaxor phase boundary in the BNKT-KxNN system and the tolerance factor t of the end number (KxNN). In situ high-energy X-ray scattering experiments with external field reveals that the large strain response in the studied system is likely related to the electric field-induced distortion from the pseudocubic structure.

Due to the coupling effect of SPPs excited by the incident electromagnetic field, the metallic nanorods structures show special optical properties that can be applied in many fields of nano-technology. The excitation efficiency spectrums of the two parallel nanorods and the π-shaped nanorods structures are calculated by FDTD method, respectively, which show different SPR peak positions under the same conditions for these two structures. The high numerical aperture focusing processes through these two structures are simulated by 3D FDTD method. The results show that the π-shaped nanorods perform better electromagnetic field far field transfer efficiency than the two parallel nanorods. Finally the focusing process through the angular π-shaped nanorods structure is investigated, which indicates that the focal field can be transferred to different directions away from the optical axis of the focal beam.

The transmission line theory (TLT) and the finite difference time domain (FDTD) method are applied to investigate the optical transmission characteristics of the metal–dielectric–metal (MDM) plasmonic waveguide coupled with a stub structure. The transmission rate of the FDTD simulation results demonstrates periodically variation from less than 1% to more than 92% as a function of the length of the stub, which fits well with the results of TLT. Furthermore, the transmission also performs a periodically switch distribution with the change of the refractive index of the stub from 1.0 to 2.0 gradually. Both methods are adopted for modulating the superposition phase of the interference between the reflected surface plasmon polaritons (SPPs) wave from the end of the stub and the passing SPPs wave in the waveguide, which can be interpreted as the principle mechanism for the optical switch effect of the MDM waveguide with a stub structure.

The machine vision system has already become the optical mechanical electrical integration products or components of products in modern equipment manufacturing industry. The new LED is more excellent than the halogen tungsten lamp, laser and other traditional light source. It is used in machine vision system more and more. From the analysis of the functional characteristics, this article pointed out the difference between machine vision LED lighting system and traditional optical instrument lighting system. By the interactive methods which integrate with synthesis design analysis and Simulation, this paper import the element of field flattening theory into traditional lighting design, making it a kind of the new flat field lighting system. The effect when it was applied to high power LED lighting system is good. With the new design concept, through the interactive design method and the new image quality evaluation system, we have a contrast experiment on a kind of LED single lamp lighting system. The results show that the field flat lighting system is superior to the traditional one. The most distinctive feature of the new light system is that, it can improve the performance of critical illumination system in certain procedures -- poor illumination uniformity performance. This new lighting optical structure and the new lighting quality evaluation system have broad prospects.

Objective Recent studies indicated that resistin and adiponectin take some roles in the glucose homeostasis and suggested there were associations among resistin, adiponectin and glucose tolerance. Therefore we investigate the serum levels of resistin and adiponectin in impaired glucose tolerance (IGT) cases in the present study. Methods 82 subjects were included, divided into IGT group (27 cases) and normal glucose tolerance (NGT) group (55 subjects) based on the oral glucose tolerance test. Body mass index (BMI), waist circumference, blood pressure, fasting lipids, glucose, insulin and C-peptide were measured, and adipocytokines such as resistin, adiponectin, leptin, TNF-α, interleukin-6 (IL-6) and C-response protein (CRP) were also examined, insulin resistiance was assayed by the homeostasis model assessment of insulin resistance (HOMA-IR) formula. Results There were no differences in concentrations of resistin and adiponectin between IGT group and NGT group. Pearson relation analysis showed that serum resistin concentrations were positively correlated with age (r=0.482, p Conclusions In IGT cases, serum resistin and adiponectin concentrations are normal, however, serum resistin concentrations were higher in IGT cases with overweight and obesity while adiponectin were higher in female IGT case.