Microwave Characteristics Analysis of Typical Photosensitive Material InP under Weak Light Irradiation Based on Quasi-Optical Resonator

Yafeng Li,En Li,Chengyong Yu,Chong Gao,Gaofeng Guo,Yong Gao 대한금속·재료학회 2020 ELECTRONIC MATERIALS LETTERS Vol.16 No.2

In this paper, the microwave characteristics of typical photosensitive material InP under diff erent light irradiation are studied. The measurement sensor is a refl ection-type hemispherical quasi-optical resonator with an operating frequency range from 20to 40 GHz, an operating mode of TEM 00q , and a quality factor of 18,000 or more. For the short-time irradiation experiment,the variation of InP microwave characteristics with the irradiation power of 20 mW, 60 mW, 100 mW, and 200 mW, is studiedby frequency-domain and time-domain scanning methods, respectively. The measurement results indicate that the microwavecharacteristics of InP change signifi cantly even under weak light irradiation. Taking 100 mW and 200 mW irradiation poweras examples, the long-time irradiation experiment performed on InP lasting 1.5 min is carried out. The measurement resultcurves clearly show the infl uence of the thermal and non-thermal eff ects on the InP microwave characteristics at the instantof the monochrome light source opening and closing and during irradiation. Furthermore, the temperature distribution ofInP during 200 mW irradiation is real-time imaged by a thermal infrared imager to verify the existence of thermal eff ectduring irradiation. The measurement results are in good agreement with the theoretical analysis.

Research on a New Class of Planar Tensegrity Trusses Consisting of Repetitive Units

Sili Li,Xian Xu,Jiaqi Tu,Yafeng Wang,Yao-Zhi Luo 한국강구조학회 2020 International Journal of Steel Structures Vol.20 No.5

Tensegrity structure is a prestressed self-equilibrated system consisting of compressed struts and tensioned cables. Planar truss is one of the most common forms of engineering structures with a wide application. This paper proposes a new class of planar tensegrity trusses whose prototype is unintentionally found by a topology optimization algorithm. The prototype truss is composed of two basic units which are combined alternately. In this paper, the state of prestress of the truss is analytically determined from the equilibrium conditions. The stiff ness and strength of the structure are analytically formulated by using the principle of virtual work. Parametric analysis of geometrical parameters on the stiff ness and strength of the structure is carried out. By changing the shape of the basic units, the uniform planar tensegrity truss is extended to a fi sh-bellied truss. Parametric analysis is also carried out for the fi sh-bellied truss. An example of extending the planar tensegrity truss into a three-dimensional latticed tensegrity truss is also given.

Preparation of corn straw based spongy aerogel for spillage oil capture

Yuan Li,Xiaodong Liu,Weijie Cai,Yafeng Cao,Yanfeng Sun,Fengzhi Tan 한국화학공학회 2018 Korean Journal of Chemical Engineering Vol.35 No.5

This work mainly focused on the preparation of a low-cost, ultralight absorbent from renewable corn straw and filter paper via a facile and environmental-friendly approach containing high-shear blending and freeze-drying operation. The physicochemical properties of aerogel were thoroughly examined by several characterization techniques. The satisfactory hydrophobicity of the spongy aerogel was attributed to the formation of polysiloxane on the surface of methyltrimethoxysilane (MTMS) by the silanization reaction. Owing to its superior features, such as ultralow density, high porosity, desirable hydrophobicity, the corn straw based spongy aerogel exhibited a remarkable absorption capacity for both crude oil (36 g/g) and common organic solvents including carbon tetrachloride (CCl4, 45 g/g), dimethyl sulphoxide (DMSO, 24 g/g), N, N-dumethylformamide (DMF, 45 g/g). This might shed light on the design of efficient adsorbent for oil spills and organic pollutants to meet with the sustainable development.

A throughput aware with collision-free MAC for wireless LANs

Pei, Tingrui,Deng, Yafeng,Li, Zhetao,Zhu, Gengming,Pan, Gaofeng,Choi, Youngjune,Sekiya, Hiroo Springer Science + Business Media 2016 Science China. Information sciences Vol.59 No.2

Preparation of magnetic metal-organic frameworks with high binding capacity for removal of two fungicides from aqueous environments

Jiping Ma,Shuang Li,Gege Wu,Maryam Arabi,Feng Tan,Yafeng Guan,Jinhua Li,Lingxin Chen 한국공업화학회 2020 Journal of Industrial and Engineering Chemistry Vol.90 No.-

A novel kind of Zr-based magnetic metal-organic frameworks (MMOFs) was prepared by immobilizationof UiO-66 onto Fe3O4@SiO2 particles via an efficient one-pot solvothermal method. Subsequently, it wasused for adsorptive removal of triclosan (TCS) and triclocarban (TCC) fungicides from aqueousenvironments by magnetic solid phase separation. Morphology and physical/chemical features of theMMOFs were fully characterized by XRD, SEM, TEM, FT-IR, and VSM etc., showing high specific surfacearea, appropriate functionality, and desirable magnetic property. Several main factors affecting theadsorption performances of TCS and TCC on the MMOFs were systematically investigated and optimized,such as pH value of water sample, amounts/types of adsorbent and salinity. Under the optimizedconditions, short adsorption equilibrium time (only 25 min) and outstanding saturated adsorptioncapacities (476.27 and 602.40 mg g 1 for TCS and TCC, respectively) were the remarkable superiorities ofthe MMOFs compared with that of most reported adsorbents. The MMOFs demonstrated excellentadsorption selectivity for TCS and TCC and anti-interference ability. Also, the reusability for at least 11cycles was another major profit of the MMOFs that saved cost and prevented waste. Moreover, theMMOFs demonstrated satisfactory removal/purification ability for actual environmental water samples. These benefits propounded a promising outlook of employing the MMOFs for influential removal ofpollutants with considerable reliability in thefield of wastewater treatment.

Few-Layered MoS2 Nanoparticles Loaded TiO2 Nanosheets with Exposed {001} Facets for Enhanced Photocatalytic Activity

Chujun Chen,Xia Xin,Jinniu Zhang,Gang Li,Yafeng Zhang,Hongbing Lu,Jianzhi Gao,Zhibo Yang,Chunlan Wang,Ze He 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2018 NANO Vol.13 No.11

To improve the high charge carrier recombination rate and low visible light absorption of {001} facets exposed TiO2 [TiO2(001)] nanosheets, few-layered MoS2 nanoparticles were loaded on the surfaces of TiO2(001) nanosheets by a simple photodeposition method. The photocatalytic activities towards Rhodamine B (RhB) were investigated. The results showed that the MoS2–TiO2(001) nanocomposites exhibited much enhanced photocatalytic activities compared with the pure TiO2(001) nanosheets. At an optimal Mo/Ti molar ratio of 25%, the MoS2–TiO2(001) nanocomposites displayed the highest photocatalytic activity, which took only 30 min to degrade 50mL of RhB (50 mg/L). The active species in the degradation reaction were determined to be hþ and OH according to the free radical trapping experiments. The reduced charge carrier recombination rate, enhanced visible light utilization and increased surface areas contributed to the enhanced photocatalytic performances of the 25% MoS2–TiO2(001) nanocomposites.

Visual Attention Model Based on Particle Filter

( Long Liu ),( Wei Wei ),( Xianli Li ),( Yafeng Pan ),( Houbing Song ) 한국인터넷정보학회 2016 KSII Transactions on Internet and Information Syst Vol.10 No.8

The visual attention mechanism includes 2 attention models, the bottom-up (B-U) and the top-down (T-D), the physiology of which have not yet been accurately described. In this paper, the visual attention mechanism is regarded as a Bayesian fusion process, and a visual attention model based on particle filter is proposed. Under certain particular assumed conditions, a calculation formula of Bayesian posterior probability is deduced. The visual attention fusion process based on the particle filter is realized through importance sampling, particle weight updating, and resampling, and visual attention is finally determined by the particle distribution state. The test results of multigroup images show that the calculation result of this model has better subjective and objective effects than that of other models.