Model for Predicting Resilient Modulus of Unsaturated Subgrade Soils in South China

Yongsheng Yao,Jianlong Zheng,Junhui Zhang,Junhui Peng,Jue Li 대한토목학회 2018 KSCE JOURNAL OF CIVIL ENGINEERING Vol.22 No.6

Subgrade soils are often unsaturated and the resilient modulus (MR) of subgrade soils is usually subjected to the climate environment andtraffic loading in the field. Therefore, the Matric Suction (MS) and traffic loading are considered to be two important parametersassociated to the MR prediction model. To verify the MR prediction model, the MS of the typical subgrade soil were determined throughthe pressure plate test. In this study, the soil-water characteristic curves were also described using the Fredlund & Xing’s model. Then,the dynamic MR of the typical subgrade soil under various stresses and water contents was measured. After that, a new prediction modelwas proposed with the model variables including the minimum bulk stress, octahedral sheer stress and matric suction, and the validity ofthe new model was verified by previous research results. Finally, the correlations between the physical properties of subgrade soilsincluding the percentage passing through the No. 200 sieve (0.075 mm), plasticity index, liquid limit, dry density and the regressioncoefficients of the new model were established. The results show that the new model can be used to predict the MR well, and it effectivelysolves the problem that the bulk stress is equal with a different combinations of the confining pressure and deviator stress. At the sametime, the MR can be predicted much more easily with physical parameters of subgrade soils rather than conducting triaxial tests.

Zwitterion imprinted composite membranes with obvious antifouling character for selective separation of Li ions

Yao Lu,Dongshu Sun,Yang Lu,Yongsheng Yan,Bo Hu 한국화학공학회 2020 Korean Journal of Chemical Engineering Vol.37 No.4

A surface hydrophilic and antifouling imprinted composite membrane based on zwitterion and dopamine for selective adsorption Li+ from compound has great potential. We investigated the selective adsorption amount for lithium from high Mg2+ and low Li+; the resulting displayed both excellent adsorption amount of Li+ and high selective adsorption efficiency of the fabricated membranes from the compound. Relatively lower contact angle of 50.7o and higher membrane flux value of 11.78mL cm2 min1 were obtained, which indicated the imprinted composite membrane possessed high hydrophilicity. In the BSA protein adsorption experiments, the anti-pollution performance of the imprinted composite membrane was greatly improved. Moreover, the results on perm-selectivity and regeneration ability are 8.94 and 91.4%. Overall results suggest that zwitterion and dopamine can be considered effective for increasing the hydrophilicity and anti-pollution capacity. Moreover, the imprinted composite membranes could be used for selective adsorption of Li+ effectively.

Solvothermal-Assisted Synthesis of Biomass Carbon Quantum Dots/Bismuth Oxyiodide Microflower for Enhanced Photocatalytic Activity

Xin Yao,CHANGCHANG MA,Hai Huang,Zhi Zhu,Hongjun Dong,Chunxiang Li,Wenli Zhang,Yongsheng Yan,Yang Liu 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2018 NANO Vol.13 No.3

In this paper, the biomass carbon quantum dots (CQDs) modified flower-like BiOI (CQDs/BiOI) composite photocatalyst was synthesized by a facile solvothermal method. Compared with the pristine BiOI, the biomass CQDs/BiOI exhibited outstanding photocatalytic activity for degradation of the typical methylene blue (MB) under visible light irradiation since the biomass CQDs could act as electron acceptors to effectively facilitate the separation efficiency of photon-generated carriers and prolong their lifetime. Furthermore, the mechanism detection experiment showed that the ·O2 - and H+ were major activity species, and the photocatalytic electron transfer mechanism was further investigated. This work provided a new insight into biomass CQDs effects and took an important step toward the development of improving Bi-based semiconductor photocatalyst activity.

HYDROTHERMAL SYNTHESIS AND ENHANCED VISIBLE-LIGHT PHOTOCATALYTIC ACTIVITY OF CdS QUANTUM DOTS SENSITIZED CARBON NANOTUBES (CNTs) NANOCOMPOSITE

XINLIN LIU,Yongsheng Yan,Qian Wang,Peng Lv,GUANXIN YAO,CHANGCHANG MA,Yan Yan,Yanfeng Tang 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2014 NANO Vol.9 No.2

A new-type photocatalyst of cadmium sul¯de carbon nanotubes (CdS/CNTs) was prepared bythe hydrothermal method. This as-prepared CdS/CNTs composite photocatalyst was proved toexhibit an excellent photocatalytic activity for degradation of tetracycline (TC). Specially, the95%-CdS – 5%-CNTs composite photocatalyst played the best degradation rate (81.2%) in 60 minunder the visible light irradiation. Moreover, this 95%-CdS – 5%-CNTs composite photocatalystpossessed great stability and could be used at least four cycles with almost no loss of photo-catalytic e±ciency. Furthermore, the as-synthesized CdS/CNTs composite photocatalyst wascharacterized by X-ray di®raction (XRD), transmission electron microscopy (TEM), UV-Visdi®used re°ectance spectra (UV-Vis), Raman and thermal gravimetry (TG). In addition, thepossible mechanism and kinetics of photodegradation of TC with CdS/CNTs photocatalyst wasalso discussed.

A review of the current in-situ fouling control strategies in MBR: Biological versus physicochemical

Qiang Liu,Jiayao Ren,Yongsheng Lu,Xiaolei Zhang,Felicity A. Roddick,Linhua Fan,Yufei Wang,Huarong Yu,Ping Yao 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.98 No.-

Fouling in membrane bioreactors (MBR) is a bottleneck problem limiting their application. In-situfouling control strategies have been continuously developed for decades, and can be mainlycategorized as biological and physicochemical approaches. However, the mechanisms and performanceof these methods as well as their application prospects have not been thoroughly discussed andcompared in a systematic manner. This study was aimed at providing a detailed review on the variousin-situ biological and physicochemical methods in terms of fouling control performance, foulingreduction mechanisms and practicability. This involves a comparison of the popular biological controlstrategies including quorum quenching (QQ)) and physicochemical approaches such as NaClObackflushing, hybrid electrochemical MBR and anti-biofouling membrane development, with theanalysis of their potential, existing issues and practicality in full-scale applications. Future work is alsorecommended for developing more sustainable and more widely applicable MBR fouling controlstrategies.

Selection of inspection path optimization scheme based on analytic hierarchy process and inspection experimental study

Shuo Zhang,Jiantao Yao,Ruochao Wang,Yu Tian,Jiaxin Wang,Yongsheng Zhao 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.1

This paper mainly studies the optimization of the patrol route of a fire inspection robot, based on analytic hierarchy process (AHP) and fire source detection. First, the A* algorithm is improved based on two aspects of the heuristic function and of the obstacle boundary setting, while the suboptimal path is obtained in MATLAB. Next, the path planned according to the improved A* algorithm is smoothed and optimized, by means of gradient descent method, Bezier curve and B-spline curve, while the index parameters are optimized by means of MATLAB simulation. In view of the simulation results, the trajectory optimization performance index evaluation system, established by five decision criteria, including running time, path length, ride comfort, no-collision effect and quadratic optimization space, is put forward. The three kinds of optimization methods are analyzed qualitatively and quantitatively, and the results show that, in the total hierarchical ranking, the B-spline curve trajectory optimization scheme has the largest weight and is more important than the other two schemes. Finally, the superiority of B-spline curve is verified experimentally.

Computing Pore Size Distribution in Non-woven Fibrous Filter Media

He Bai,Xiaoming Qian,Jintu Fan,Yao Qian,Yongchao Duo,Yongsheng Liu,Xiaobo Wang 한국섬유공학회 2020 Fibers and polymers Vol.21 No.1

Fundamental understanding of transport properties of non-woven fibrous material is depended on in dept cognitionof their microstructure. Non-woven fibrous filter media are formed by the random distribution of fibers in a specific spaceexhibit a complicated pore size structure. Computing pore size distribution (PSD) is a vital parameter in studying materialtransport dynamics. In this work, a theoretical model was suggested based on the gamma distribution and fiber orientationdistribution to predict the PSD in non-woven fibrous filter media. In parallel, the analytical model was compared with theprevious PSD theories and experimental results. The 3D virtual fiber structure was constructed by using GeoDict code, andthe pore size was represented by the inscribed circle diameter. Parameters influencing the PSD were studied, including fiberdiameter, porosity, and fiber orientation. Comparison of simulation results with analytical model was made. The resultsdemonstrate that the angle between the fiber and the Z-axis has little effect on the PSD. When the porosity is consistent,smaller pores can be formed by reducing fiber diameter. With the fiber diameter is constant, larger pores can be formed byincreasing the porosity.

Heterologous Expression and Characterization of a Laccase from Laccaria bicolor in Pichia pastoris and Arabidopsis thaliana

( Bo Wang ),( Ying Yan ),( Jing Xu ),( Xiaoyan Fu ),( Hongjuan Han ),( Jianjie Gao ),( Zhenjun Li ),( Lijuan Wang ),( Yongsheng Tian ),( Rihe Peng ),( Quanhong Yao ) 한국미생물 · 생명공학회 2018 Journal of microbiology and biotechnology Vol.28 No.12

Laccases can oxidize a variety of phenolic and non-phenolic substrates including synthetic dyes. In this research, a laccase gene Lcc9 from Laccaria bicolor was chemically synthesized and optimized to heterogeneous expression in Pichia pastoris and Arabidopsis thaliana. The properties of recombinant laccase expressed by P. pastoris were investigated. The laccase activity was optimal at 3.6 pH and 40°C. It exhibited K_m and V_max values of 0.565 mmol l^-1 and 1.51 μmol l^-1 min^-1 for ABTS respectively. As compared with untransformed control plants, the laccase activity in crude extracts of transgenic lines exhibited a 5.4 to 12.4-fold increase. Both laccases expressed in transgenic P. pastoris or A. thaliana could decolorize crystal violet. These results indicated that L. bicolor laccase gene may be transgenically exploited in fungi or plants for dye decolorization.