摘要：We report a novel benzoxazole derivative,1,4-bis(benzo[d]oxazol-2-yl)naphthalene(BBON),exhibiting exceptional multifunctional properties for advanced optoelectronic *** crystals demonstrate remarkable multidirectional bending and twisting at room temperature and retain elasticity under extreme conditions,such as exposure to liquid nitrogen,showcasing their *** crystals can be crafted into complex mesh and lantern shapes,highlighting their versatility for flexible and wearable *** high pressure,BBON exhibits significant piezochromic shifts,with the emission wavelength shifting from 477 to 545 nm upon pressure *** crystals,with a high quantum yield of 72.26%,exhibit excellent optical waveguide performance:0.38 dB/cm when straight and 0.56 dB/cm when *** properties make them ideal for smart sensors and flexible electronic ***-crystal analyses reveal that molecular stacking and intermolecular interactions are crucial to their elastic and piezochromic properties,providing insights for the design of future responsive materials.

摘要：This study aims to explore the humanoid robot joint servo drive integration design and adaptive backstepping control. To make the humanoid robot have explosive power as the human does, simply increasing the power output of the motor of a lightweight design cannot meet the demand of moving heavy objects and so on. Moreover, the backstepping control algorithm is designed to implement the dual-arm cooperative control. The joint servo drive is redesigned in the present study, which can drive the motor at a limitation state when needed output high-voltage pulse can stimulate the motor so that the motor can produce an instantaneous large torque. A miniature design scheme is presented in this study for the servo drive, explaining the design method of each part module. The ex- perimental data illustrate that the servo drive can produce an output torque greater than the rate of the high-voltage pulse that stimulates the motor. Knowledge of the control of humanoid robot moving a heavy object has important practical significance. The present study provides a complete actual problem and exhibits a real practical use case which can be used to speed up the explosive humanoid robot arms.

摘要：Based on angular amplitude modulation of orthogonal base vectors in common-path interference method, we propose an interesting type of hybrid vector beams with unprecedented azimuthal polarization gradient and demonstrate in experiment. Geometrically, the configured azimuthal polarization gradient is indicated by intriguing mapping tracks of angular polarization states on Poincaré sphere, more than just conventional circles for previously reported vector beams. Moreover, via tailoring relevant parameters, more special polarization mapping tracks can be handily achieved. More noteworthily, the designed azimuthal polarization gradients are found to be able to induce azimuthally non-uniform orbital angular momentum density, while generally uniform for circle-track cases, immersing in homogenous intensity background whatever base states are. These peculiar features may open alternative routes for new optical effects and applications.

摘要：A VUV beamline at the Shanghai Synchrotron Radiation Facility （SSRF） for angle-resolved photoelectron spectroscopy （ARPES） measurements is designed. To increase the resolution and bulk sensitivity, a photon energy as low as 7 eV is desired. Because the reflectivity for p-polarized photons strongly decreases when the photon energy is below 30 eV, the design of a high flux beamline for low energy VUV photons is a challenge. This work shows a variable including angle Varied Line-space Plane-Grating Monochromator （VLPGM） with varied grating depth （VGD） which can achieve both high resolution and high flux with broad energy coverage.

摘要：Advances in the photocurrent conversion of two-dimensional (2D) transition metal dichalcogenides have enabled the realization and application of ultrasensitive and broad-spectral photodetectors. The requirements of previous devices constantly drive for complex technological implementation, resulting in limits in scale and complexity. Furthermore, the development of large-area and low-cost photodetectors would be beneficial for applications. Therefore, we demonstrate a novel design of a heterojunction photodetector based on solution-processed ultrathin MoSe2 nanosheets to satisfy the requirements of its application. The photodetector exhibits a high sensitivity to visible–near infrared light, with a linear dynamic range over 124 decibels (dB), a detectivity of ~1.2 × 1012Jones, and noise current approaching 0.1 pA·Hz–1/2at zero bias. Significantly, the device shows an ultra-high response speed up to 30 ns with a 3-dB predicted bandwidth over 32 MHz, which is far better than that of most of the 2D nanostructured and solution-processable photodetectors reported thus far and is comparable to that of commercial Si photodetectors. Combining our results with material-preparation methods, together with the methodology of device fabrication presented herein, can provide a pathway for the large-area integration of low-cost, high-speed photodetectors. [Figure not available: see fulltext.] © 2016, Tsinghua University Press and Springer-Verlag Berlin Heidelberg.

摘要：All commercial electron spin polarimeters work in single channel mode, which is the bottleneck of researches by spin-resolved photoelectron spectroscopy. By adopting the time inversion antisymmetry of the magnetic field, we developed a multichannel spin polarimeter based on normal incident very low energy electron diffraction （VLEED）. The key point to achieve the multi-channel measurements is the spatial resolution of the electron optics. The test of the electron optics shows that the designed spatial resolution can be achieved and an image type spin polarimeter with 100 times 100, totally ten thousand channels is possible to be realized.

摘要：The thermal conduction of suspended few-layer hexagonal boron nitride （h-BN） sheets was experimentally investigated using a noncontact micro-Raman spectroscopy method. The first-order temperature coefficients for monolayer （1L）, bilayer （2L） and nine-layer （9L） h-BN sheets were measured to be -（3.41 ± 0.12）× 10-2, -（3.15 ± 0.14） × 10-2 and -（3.78 ±0.16）× 10-2 cm-1.K-1, respectively. The room-temperature thermal conductivity of few-layer h-BN sheets was found to be in the range from 227 to 280 W.m-1-K-1, which is comparable to that of bulk h-BN, indicating their potential use as important components to solve heat dissipation problems in thermal management configurations.

摘要：Actinide-based catalysts have been regarded as promising candidates for N_(2) fixation owing to their unique 5f orbital with flexible oxidation ***,we report for the first time the dispersion of uranium(U)single atoms on TiO_(2) nanosheets via oxygen vacancy confinement for N_(2) *** single-atom U catalyst exhibited a high NH_(3) yield of 40.57μg h^(-1) mg^(-1),with a reasonably high Faraday efficiency of 25.77%,ranking first among the reported nitrogen-free ***-labeling operando synchrotron infrared spectroscopy verifies that the key*N_(2)H_(y) intermediate species was derived from the N_(2) gas of the *** using operando X-ray absorption spectroscopy,we found enhanced metal-support interaction between U single atoms and TiO_(2) lattice with more U-O_(latt) coordination under working *** simulations suggest that the evolved 1O_(ads)-U-4O_(latt) moieties act as a critical electronfeedback center,lowering the thermodynamic energy barrier for the N_(2) dissociation and the first hydrogenation *** work provides the possibility of tailoring the interaction between metal active sites and supports for designing high-performance actinide-based single-atom catalysts.

摘要：We have designed and synthesized NaGdF4：Nd^3＋, Yb^3＋, Tm^3＋. magnetic nano- phosphors with combined dual-mode downconversion （DC） and upconversion （UC） photoluminescence upon 800 run excitation. Hexagonal-phase NaGdF4：Nd^3＋, Yb^3＋, Tm^3＋ nanocrystals （NCs） with an average size of 21 nm were synthesized using a solvothermal approach. Nd^3＋, Yb^3＋, Tm^3＋ triple-doped NaGdF4 NCs exhibit a broad range of photoluminescence peaks covering a near infrared first/second window （860-900, 1,000, and 1,060 nm）, and visible emission including blue （475 nm）, green （520 and 542 nm） and yellow （587 nm） after excitation at 800 nm. A mechanism involving circulation of energy over Gd^3＋ sublattices as bridge ions and final trapping by the initial activator ions （Nd^3＋） has been proposed. Penetration depth studies indicate that NIR emission is easily detected even at a large tissue thickness of 10 mm. These paramagnetic nanophosphors demonstrate a large magnetization value of 1.88 emu/g at 20 kOe and longitudinal relaxivity value of 1.2537 mM-1.S-1 as a Tl-weighted magnetic resonance imaging contrast agent. These NaGdF4：Nd^3＋, Yb^3＋ Tm^3＋ NCs are promising for applications in biological and magnetic resonance imaging.

摘要：金属负载型催化剂的界面结构设计一直是实现高效、高选择性催化反应的核心研究.本文表明,异质结结构PdNi&Ni_(3)N的界面电荷重新分布可以催化硝基苯选择性加氢成为偶氮类化合物.相比之下,独立的PdNi合金催化硝基苯转化为苯胺,而Ni_(3)N载体在相同条件下对硝基苯加氢的催化几乎没有效果. X射线光电子能谱和理论计算表明,PdNi&Ni_(3)N界面电荷重新分布导致有机反应中间体的吸附能发生变化,从而改变加氢反应途径,实现偶氮化合物的高选择性生成.本研究进一步表明了界面结构设计在有机催化加氢反应中的重要性,而且可能会引起研究者对于异质结构金属(合金)/过渡金属氮化物更多的科学兴趣,以应用于催化领域的不断发展.