摘要：Heteroatom-doped Pt-based nanocrystals have generated considerable interest and hold great prospects in heterocatalysis. However, engineering the superficial atomic configurations of these nanocrystals via in situ surface doping remains exceedingly challenging. Herein, we propose a onepot, in situ surface doping chemical synthesis protocol to prepare quatermetallic Pt Ni Co Rh dendritic nanocrystals as versatile and active catalysts for the electrooxidation of C_(1) fuels. Leveraging the selective coordination effect between ascorbic acid and Rh^(3+)ions, the doping of trace Rh atoms can be guided specifically at the near-surface of Pt Ni Co Rh nanocatalysts. Electrocatalytic tests indicate that Pt_(67)Ni_(16)Co_(16)Rh_(1) nanocrystals with in situ trace Rh-doped surface exhibit substantially enhanced activity, durability, and CO tolerance for the electrooxidation of methanol, formaldehyde, and formic acid. In situ Fourier transform infrared spectroscopy provides molecular-level insight into the exceptional performance of these nanocatalysts. The surface incorporation of anticorrosive Rh atoms enables the transfer of CO intermediates from the atop Pt sites to the bridged Rh–Pt surface sites,thereby facilitating the elimination of these poisoning species from the catalyst surface. This study presents an effective in situ surface doping strategy which can enable the design of more atom-economic heterocatalysts.

摘要：With the significant discharge of antibiotic wastewater into the aquatic and terrestrial ecosystems, antibiotic pollution has become a serious problem and presents a hazardous risk to the environment. To address such issues, various investigations on the removal of antibiotics have been undertaken. Photocatalysis has received tremendous attention owing to its great potential in removing antibiotics from aqueous solutions via a green, economic, and effective process. However, such a technology employing traditional photocatalysts suffers from major drawbacks such as light absorption being restricted to the UV spectrum only and fast charge recombination. To overcome these issues, considerable effort has been directed towards the development of advanced visible light-driven photocatalysts. This mini review summarises recent research progress in the state-of-the-art design and fabrication of photocatalysts with visible-light response for photocatalytic degradation of antibiotic wastewater. Such design strategies involve the doping of metal and non-metal into ultraviolet light-driven photocatalysts, development of new semiconductor photocatalysts, construction of heterojunction photocatalysts, and fabrication of surface plasmon resonance-enhanced photocatalytic systems. Additionally, some perspectives on the challenges and future developments in the area of photocatalytic degradation of antibiotics are provided.

摘要：Artificial modulation of electronic structures and control of the transport dynamics of carriers and excitons in Cd Se nanowire are important for its application in optoelectronic nanodevices. Here, we demonstrate the aggregative flow of excitons by bending Cd Se nanowires. The bending strain induces spatial variance of bandgap, and the energy bandgap gradient will result in the flow of excitons towards the bending outer edge of Cd Se nanowire. The exciton emission energy shows a uniform redshift in the bending region due to the aggregative flow of excitons, and the energy redshift increases linearly with increasing the strain at the outer edge of the Cd Se nanowire. Our results show an effective method to drive, concentrate, and utilize the excitons in Cd Se nanowires, which provides a guide for the design of high performance and flexible optoelectronic nanodevices.

摘要：Pump chambers, normally used as dominant structures in mining engineering to insure the safety and production of un-derground coal mines, become generally deformed under conditions of deep mining. Given the geology and engineering condition of Qishan Coal Mine in Xuzhou, the failure characteristics of pump chambers at the –1000 m level show that the main cause can be attributed to the spatial effect induced by intersectional chambers, where one pump is constructed per well. We developed an opti-mized design of the pump room, in which the pump wells in the traditional design are integrated into one compounding well. We suggest that the new design can limit the spatial effect of intersectional chambers during construction given our relevant numerical simulation. The new design is able to simplify the structure of the pump chamber and reduce the amount of excavation required. Based on a bolt-mesh-anchor with a rigid gap coupling supporting technology, the stability of pump chamber can be improved greatly.

摘要：The high-temperature methanation of CO is an important reaction in the processes used to produce substitute natural gas,while the Ni-based catalysts prepared using the conventional impregnation method tend to deactivate under high-temperature reaction conditions. This paper describes the design and assembly of ordered mesoporous alumina(OMA) using highly disperse ~5 nm nickel nanoparticles(Ni NPs),via a one-pot,evaporation-induced self-assembly(EISA) method. Small-angle X-ray diffraction(XRD),transmission electron microscope(TEM),and N2 adsorption and desorption results revealed that this catalytic material had highly ordered mesopores,which were retained even after long-term stability tests. The catalyst exhibited excellent sintering-resistant and anti-coking properties in high-temperature CO methanation reactions(60% CO conversion after 50 hours of accelerated deactivation at 700°C). The improved catalytic performance was attributed to the matrix of the OMA,which effectively improved the dispersion of the nickel particles,and prevented the Ni NPs from sintering,via a particle migration and coalescence mechanism. The NiOMA catalyst demonstrated here shows promise for high-temperature methanation.

摘要：The problems of joint adaptive waveform design and baseline range design for bistatic radar to maximize the practical radar resolution were *** from the conventional ambiguity function(AF)-based resolution which is only related with the transmitted waveform and bistatic geometry and could be regarded as the potential resolution of a bistatic radar system,the practical resolution involves the effect of waveform,signal-to-noise ratio(SNR)as well as the measurement ***,it is more practical and will have further significant application in target detection and *** constraint optimization procedure of joint adaptive waveform design and baseline range design for maximizing the practical resolution of bistatic radar system under dynamic target scenario was *** results show that the range and velocity resolution are enhanced according to the adaptive waveform and bistatic radar configuration.

摘要：针对具有参数不确定性的欠驱动四旋翼无人飞行器,设计了一种非线性飞行控制器.该控制器主要采用非线性鲁棒以及在线参数估计算法.利用基于李亚普诺夫稳定性分析方法,证明了这种控制器可以使四旋翼无人飞行器的x,y,z方向的位移跟踪参考轨迹,偏航角ψ稳定到任意点,并且达到全局最终稳定的控制效果.同时相对于一般的滑模控制算法,本文提出的控制器消除了颤振现象.数值仿真结果表明,本文提出的控制设计具有良好的控制效果.

摘要：Four optimal approaches of high-order finite-impulse response(FIR) digital filters were developed for designing four types filters using neural network algorithms. The solutions were presented as parallel algorithms to approximate the desired frequency response specification. Therefore, these methods avoid matrix inversion, and make a fast calculation of the filter’s coefficients possible. The convergence theorems of these proposed algorithms were presented and proved to illustrate them stable, and the implementation of these methods was described together with some design guidelines. The simulation results show that the ripples of the designed FIR filters are significantly little in the pass-band and stop-band, and the proposed algorithms are of fast convergence.

摘要：A kind of erbium doped photosensitive fiber(EDPF) was proposed and fabricated,whose core was made of double layers named photosensitive layer and erbium doped *** double-layer core de-sign can overcome difficulties in fabrication of EDPF with single core design,*** conflict between the high consistency rare earth doping and high consistency germanium doping.A sample was fabri-cated through the modified chemical vapor deposition method combined with solution doping *** peak absorption coefficient was 48.80 dB/m at 1.53 μm,the background loss was lower than 0.1 dB/m,and the reflectivity of the fiber Brag gratings(FBG) written directly on the sample fiber was up to 97.3% by UV-writing ***,a C band tunable fiber laser was fabricated using the sample fiber,in which a uniform FBG was written directly on EDPFs as a reflector.A single wavelength lasing with a maximum wavelength tuning range of 1555.2―1558.0 nm was achieved *** this tuning range,the full-width at half maximum(FWHM) of the laser output was smaller than 0.015 nm and the side mode suppression ratio(SMSR) was better than 50 dB.

摘要：Two photolabile amphiphilic supramolecules were designed and synthesized with mono-dendrite and tri-dendrite, which can reversibly self-assemble to spheroid and wedge-shaped nanoparticles. With multiple branches of terminal amine labeled PEG, these nanoparticles can associate with a negatively charged oligonucleotide and their usage for oligonucleotide delivery was evaluated. Oligonucleotide/nanoparticle complex containing tri-dendrite can efficiently deliver oligonucleotide into cells via endocytosis, while the complex containing mono-dendrite almost lost their ability to deliver oligonucleotide. Further light activation triggered the dissociation of tri-dendrite supramolecular assembly via 1,4- and 1,6-quinone-methide rearrangement, leading to the efficient unpacking of the oligonucleotide in cells.