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The effect of interfacial diffusion on device performance of polymer solar cells: a quantitative view by active-layer doping

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Science China Chemistry 2015年第2期58卷 317-322页

作者： Li Nian Jiadong zhou kai Zeng Xiaoyan Wu Linlin Liu Zengqi Xie Fei huang Yuguang Ma Institute of Polymer Optoelectronic Materials and Devices State Key Laboratory of Luminescent Materials and Devices South China University of Technology

The diffusion of constituent materials at interfaces is one of the key factors for device performance and stability. In this work, the effect of interfacial diffusion of a classic interfacial material PFN on device performance of polymer solar cells was studied quantitatively by doping PFN into active layer based on P3HT：PC61BM blend. The PCEs of devices with 550 ppm PFN de- crease to half compared to those of the control devices without PFN, which are mainly attributed to the decrease of short-circuit current （Jsc） and fill factor （FF）. Advanced analyses of equivalent circuit, absorption spectra, and atomic force mi- croscopy indicates that the presence of PFN in the active layer increases the leakage current, decreases the aggregation of P3HT, and reduces the phase separation. This research reveals the physical mechanism of interfacial diffusion in device per- forrnance and provides a basis for further improving the performance and stability of PSCs.

关键词： bulk-heterojunction solar cells interfacial diffusion PFN stability degradation

Low-frequency Periodic Error Identification and Compensation for Star Tracker Attitude Measurement

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Chinese Journal of Aeronautics 2012年第4期25卷 615-621页

作者： WANG Jiongqi XIONG kai zhou Haiyin Department of Mathematics and System Science National University of Defense Technology Changsha 410073 China National Laboratory of Space Intelligent Control Beijing 100048 China

The low-frequency periodic error of star tracker is one of the most critical problems for high-accuracy satellite attitude *** this paper an approach is proposed to identify and compensate the low-frequency periodic error for star tracker in attitude *** analytical expression between the estimated gyro drift and the low-frequency periodic error of star tracker is derived *** then the low-frequency periodic error,which can be expressed by Fourier series,is identified by the frequency spectrum of the estimated gyro drift according to the solution of the first ***,the compensated model of the low-frequency periodic error is established based on the identified parameters to improve the attitude determination ***,promising simulated experimental results demonstrate the validity and effectiveness of the proposed *** periodic error for attitude determination is eliminated basically and the estimation precision is improved greatly.

关键词： star trackers attitude determination low-frequency periodic error gyro drift precision analysis

Study of RCS characteristics of tilt-rotor aircraft based on dynamic calculation approach

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Chinese Journal of Aeronautics 2022年第4期35卷 426-437页

作者： Zeyang zhou Jun huang School of Aeronautic Science and Engineering Beihang UniversityBeijing 100083China

To study the Radar Cross-Section(RCS) characteristics of the tilt-rotor aircraft, a dynamic calculation approach that takes into account rotor rotation and nacelle tilt is *** optics and physical theory of diffraction are used to deal with the instantaneous electromagnetic scattering of the target. The RCS of the aircraft in the helicopter mode, fixed-wing mode and transition mode is analyzed. The results show that in the fixed-wing mode, the blade has a weaker deflection effect on the head incident wave in the horizontal plane. The helicopter mode improves the scattering of the rotor in the horizontal plane, while it increases the scattering source on the surface of the nacelle. At a fixed tilt angle, the RCS of the aircraft under a given azimuth angle still shows obvious dynamic characteristics. Dynamic tilting significantly changes the scattering effects of blades, hubs, nacelles and wingtips. The proposed approach is shown to be feasible and effective to learn the electromagnetic scattering characteristics of the tilt rotor aircraft.

关键词： Dynamic electromagnetic scattering Nacelle tilt Radar cross-section(RCS) Tilt-rotor aircraft Transition mode

Non-reciprocal Sound Transmission in Electro-acoustic Systems with Time-Modulated Circuits

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Acta Mechanica Solida Sinica 2022年第6期35卷 940-948页

作者： Yu huang Xiaoming zhou Key Laboratory of Dynamics and Control of Flight Vehicle Ministry of EducationSchool of Aerospace EngineeringBeijing Institute of TechnologyBeijing100081China

Non-reciprocal sound transmission is demonstrated in an electro-acoustic system consisting of two shunt loudspeakers with time-modulated *** shunt circuit is modulated by periodically varying the resistance in time sequence,and a phase difference of time modulation is set between two sets of loudspeakers to produce a spatial *** spatiotemporal modulation of acoustic properties is thus formed to break the *** theoretical model based on the transfer-matrix method is developed to predict acoustic scatterings of electro-acoustic *** asymmetric transmission in opposite directions is disclosed by the model and is verified by time-domain simulation results based on the finite-difference time-domain *** transmission in multiple frequency bands can be created by tuning circuit parameters,showing their ability in regulating acoustic non-reciprocal *** study may provide a platform for the design of compact and non-reciprocal acoustic devices with applications to efficient noise control.

关键词： Non-reciprocity Shunt loudspeaker Time-varying circuits Spatiotemporal modulation

Rigid ureteroscopy in prone split-leg position for fragmentation of female ureteral stones:A case report

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World Journal of Clinical Cases 2020年第7期8卷 1301-1305页

作者： kai huang Department of Urology Clinical Medicine CollegeYangzhou UniversityNorthern Jiangsu People’s HospitalYangzhou 225001Jiangsu ProvinceChina

BACKGROUND Ureteroscopy is widely used in the treatment of ureteral stones due to the increased morbidity of *** is the first report of a case of ureteral calculi treated with rigid ureteroscopy in the modified prone split-leg *** SUMMARY A 62-year-old Asian woman was diagnosed with a ureteral stone and underwent extracorporeal shock wave lithotripsy ***,the abdominal computer tomography scan showed persistent calculi on the right lower *** left hip movement was limited because of a left femoral neck fracture that did not receive proper treatment in a timely *** was unable to undergo surgery in the lithotomy position and refused to accept flexible ureteroscopy ***,rigid ureteroscopy was performed with her in the modified prone split-leg *** ureteral calculi were successfully *** It is feasible to treat lower ureteral calculi in women in the prone split-leg position with the implementation of rigid ureteroscopy.

关键词： Ureteroscopy Ureteral calculi Lithotripsy Prone position Female Case report

La/Ce-codoped Bi_2O_3 composite photocatalysts with high photocatalytic performance in removal of high concentration dye

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Journal of Environmental Sciences 2017年第10期29卷 70-77页

作者： Shuangshuang Xue Hongbo He Qizhe Fan Changlin Yu kai Yang Weiya huang Yang zhou Yu Xie School of Metallurgy and Chemical Engineering Jiangxi University of Science and Technology College of Environment and Chemical Engineering Nanchang Hangkong University

A series of La/Ce-codoped Bi2O3 composite photocatalysts were fabricated via hydrothermal–calcination process. The as-prepared products were intensively characterized by some physicochemical characterizations like N2 physical adsorption, X-ray powder diffraction（XRD）, scanning electron microscope（SEM）, transmission electron microscope（TEM）, UV–Vis diffuse reflectance（UV–Vis DRS）, Fourier transform infrared spectroscopy（FT-IR）,photoelectrochemical measurements, and photoluminescence（PL） spectroscopy. The characterization results indicated that La and Ce doping induced obvious crystal phase transformation in Bi2O3, from monoclinic to tetragonal phase. La and Ce codoping also gave rise to the obvious synergetic effects, e.g., the lattice contraction of Bi2O3, the decrease of crystal size and the increase of surface area. The photocatalytic performance of the prepared catalysts was evaluated by removal of dye acid orange II with high concentration under visible light irradiation. Results showed that La/Ce-codoped Bi2O3 displayed much higher photocatalytic performance than that of bare Bi2O3, single La or Ce doped Bi2O3 samples. The superior photocatalytic activity was mainly attributed to the improved texture and surface properties and the synergistic effects of La and Ce codoping on suppressing the recombination of photo-generated electrons（e^-） and holes（h~＋）.

关键词： Bi2O3 crystal La Ce codoping Phase transformation Dye removal Photocatalysis

Precipitation of flaky moolooite and its thermal decomposition

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International Journal of Minerals,Metallurgy and Materials 2016年第8期23卷 976-980页

作者： Jin-yu Wu kai huang School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

Moolooite particles with flaky morphology were synthesized by mixing dilute solutions of copper nitrate and sodium oxalate in the presence of citric acid. Solution p H value, citric acid concentration, and stirring were found to have large effect on the shape of the precipitated particles. Under the stirring, the radial area of flaky moolooite particles was enlarged and extended to become a thinner and larger flake. This is ascribed to growth promotion caused by the selective absorption of citric ligands onto a particular crystalline surface of the moolooite particles. Flaky shape of the moolooite particles tended to become spherical and disappeared completely when decomposed under an Ar atmosphere, leading to the formation of large porous aggregated particles composed of many tiny nanosized copper crystals.

关键词： copper oxalate citric acid nanocrystals porous materials thermal decomposition

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囊体扩张主动控制桩基水平变形机理分析

岩土工程学报 2025年第1期47卷 85-95页

作者：黄建友闫宇涛刁钰郑刚李凯贾建伟刘永超天津大学建筑工程学院天津300072 滨海土木工程结构与安全教育部重点实验室(天津大学) 天津300072 中国建筑第五工程局有限公司湖南长沙410004 中国建筑第六工程局有限公司天津300457 天津建城基业集团有限公司天津300301

囊体扩张是一种新型地下结构变形主动控制技术,然而其在桩基变形控制机理方面尚未深入研究。采用有限元软件探究了囊体扩张控制桩基水平变形机理,分析了囊体扩张引起桩基和土体变形特性以及囊体-土体-桩体之间相互作用。结果表明:扩张直... 详细信息

囊体扩张是一种新型地下结构变形主动控制技术,然而其在桩基变形控制机理方面尚未深入研究。采用有限元软件探究了囊体扩张控制桩基水平变形机理,分析了囊体扩张引起桩基和土体变形特性以及囊体-土体-桩体之间相互作用。结果表明:扩张直径0.5 m的囊体对直径为1.2 m的桩可产生最大5.5 mm水平变形,控制效率为60%,囊体扩张对桩基水平变形控制效果良好。囊体扩张会引起邻近土体产生较大的超孔隙水压力,而孔压消散会导致土体压缩而降低桩基控制效率。当扩张距离较小时,桩径对囊体扩张控制效果影响显著。囊体扩张对桩径为0.4~1.6m的桩均有一定的变形控制效果,尤其适用于小直径桩基的变形控制。随扩张直径的增大,桩基最大水平位移近乎呈线性增大。此外,桩基水平变形随扩张距离增大而减小,但由于扩张对周围孔隙水压力影响范围有限,导致控制效率呈增大趋势。双排囊体扩张控制变形中“遮拦效应”和“反力效应”明显,控制桩基变形应遵循“先远后近,逐排扩张”的原则,以提高控制效果。

关键词：囊体扩张桩基变形控制机理分析

Synthesis of uniform hexagonal Ag nanoprisms with controlled thickness and tunable surface plasmon bands

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International Journal of Minerals,Metallurgy and Materials 2019年第6期26卷 796-802页

作者： Xing Chen Xun Liu kai huang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Lab of Green Recycling and Extraction of Metals University of Science and Technology BeijingBeijing 100083China

In this work,we synthesized monodispersed hexagonal Ag nanoprisms in high yields in a system of poly(vinylpyrrolidone)(PVP)in N-methylpyrrolidone(NMP).A blue shift occurred and was strongly dependent on the thickness of the uniform Ag nanoprisms,which had almost the same radial *** the Ag nanoprisms grew thicker,their in-plane dipole resonance peaks markedly shifted toward shorter wavelengths(i.e.,blue shift).PVP played a critical role of favoring vertical growth of the Ag nanoplates,preventing aggregation,and inducing the formation of Ag hexagonal nanoprisms(HNPs)through the transformation from thin Ag triangular nanoprisms(TNPs).Compared with similar previous research,the present study provides quite uniform Ag hexagonal nanoplates,which makes the blue shift related more solely and distinctly to the thickness of the Ag *** findings of this work provide a new perspective toward understanding the unique optical characteristics of Ag HNPs with different aspect ratios.

关键词： hexagonal nanoprisms silver nanoprisms blue shift thickness effect