Research Progress of Antibiotic Pollution and Adsorption Materials in Aquatic environment

Zheng, Kun,Deng, ChengXun,Deng, Xu,Yu, ZhiMin Urban Science Institute 2019 도시과학 Vol.8 No.2

China is the great powers of use and production of antibiotics.The current process of sewage treatment plants can not effectively remove antibiotics in water. Chinese scholars have detected different kinds of antibiotics in major waters of the country, which have potential harm to human body. Among all kinds of antibiotic treatment technologies, adsorption removal technology has the advantages of simple operation, low cost and high removal efficiency. It is a widely concerned antibiotic removal technology. However, at present, few materials have been put into practical application, and more materials with low cost and high efficiency need to be found. Different adsorptive materials have different adsorptivity to different antibiotics. For different antibiotics, different adsorptive materials can be integrated in the future, and the theory can be extended to application.

Research on Vector Spatial Data Storage Schema Based on Hadoop Platform

Kun Zheng,Yanli Fu 보안공학연구지원센터 2013 International Journal of Database Theory and Appli Vol.6 No.5

Study on Validation Method of Simulation Model Combination

Zheng Kun,Zhang Jianyan 보안공학연구지원센터 2015 International Journal of Database Theory and Appli Vol.8 No.6

Aimed at improving the efficiency of the development of complex simulation system and the problem of lower development costs, a validation development framework is proposed based on combination model. The system development process can be broken in the discovery of decomposition for the model, combination and combination of validation phase. This thesis gives the validation method based on model of tag transfer system behavior, judging by strong simulation and semantic similarity relations after the combination model of dynamic behavior and request model conforms to the degree. Simulation model combined the experimental results show that the method can automatically finish the combination of the simulation model validation, the validity of the model validation can meet the requirements of practical application.

Endophytic fungi harbored in Panax notoginseng: diversity and potential as biological control agents against host plant pathogens of root-rot disease

Zheng, You-Kun,Miao, Cui-Ping,Chen, Hua-Hong,Huang, Fang-Fang,Xia, Yu-Mei,Chen, You-Wei,Zhao, Li-Xing The Korean Society of Ginseng 2017 Journal of Ginseng Research Vol.41 No.3

Background: Endophytic fungi play an important role in balancing the ecosystem and boosting host growth. In the present study, we investigated the endophytic fungal diversity of healthy Panax notoginseng and evaluated its potential antimicrobial activity against five major phytopathogens causing root-rot of P. notoginseng. Methods: A culture-dependent technique, combining morphological and molecular methods, was used to analyze endophytic fungal diversity. A double-layer agar technique was used to challenge the phytopathogens of P. notoginseng. Results: A total of 89 fungi were obtained from the roots, stems, leaves, and seeds of P. notoginseng, and 41 isolates representing different morphotypes were selected for taxonomic characterization. The fungal isolates belonged to Ascomycota (96.6%) and Zygomycota (3.4%). All isolates were classified to 23 genera and an unknown taxon belonging to Sordariomycetes. The number of isolates obtained from different tissues ranged from 12 to 42 for leaves and roots, respectively. The selected endophytic fungal isolates were challenged by the root-rot pathogens Alternaria panax, Fusarium oxysporum, Fusarium solani, Phoma herbarum, and Mycocentrospora acerina. Twenty-six of the 41 isolates (63.4%) exhibited activity against at least one of the pathogens tested. Conclusion: Our results suggested that P. notoginseng harbors diversified endophytic fungi that would provide a basis for the identification of new bioactive compounds, and for effective biocontrol of notoginseng root rot.

Endophytic fungi harbored in Panax notoginseng: diversity and potential as biological control agents against host plant pathogens of root-rot disease

You-Kun Zheng,Cui-Ping Miao,Hua-Hong Chen,Fang-Fang Huang,Yu-Mei Xia,You-Wei Chen,Li-Xing Zhao 고려인삼학회 2017 Journal of Ginseng Research Vol.41 No.3

Background: Endophytic fungi play an important role in balancing the ecosystem and boosting host growth. In the present study, we investigated the endophytic fungal diversity of healthy Panax notoginseng and evaluated its potential antimicrobial activity against five major phytopathogens causing rootrot of P. notoginseng. Methods: A culture-dependent technique, combining morphological and molecular methods, was used to analyze endophytic fungal diversity. A double-layer agar technique was used to challenge the phytopathogens of P. notoginseng. Results: A total of 89 fungi were obtained from the roots, stems, leaves, and seeds of P. notoginseng, and 41 isolates representing different morphotypes were selected for taxonomic characterization. The fungal isolates belonged to Ascomycota (96.6%) and Zygomycota (3.4%). All isolates were classified to 23 genera and an unknown taxon belonging to Sordariomycetes. The number of isolates obtained from different tissues ranged from 12 to 42 for leaves and roots, respectively. The selected endophytic fungal isolates were challenged by the root-rot pathogens Alternaria panax, Fusarium oxysporum, Fusarium solani, Phoma herbarum, and Mycocentrospora acerina. Twenty-six of the 41 isolates (63.4%) exhibited activity against at least one of the pathogens tested. Conclusion: Our results suggested that P. notoginseng harbors diversified endophytic fungi that would provide a basis for the identification of new bioactive compounds, and for effective biocontrol of notoginseng root rot.

Perovskite-type LaFe1− xMnxO3 (x=0, 0.3, 0.5, 0.7, 1.0) oxygen carriers for chemical-looping steam methane reforming: Oxidation activity and resistance to carbon formation

Kun Zhao,Fang He,Zhen Huang,Guoqiang Wei,Anqing Zheng,Haibin Li,Zengli Zhao 한국화학공학회 2017 Korean Journal of Chemical Engineering Vol.34 No.6

The effects of Mn substitution of LaMnxFe1−xO3 (x=0, 0.3, 0.5, 0.7, 1.0) on the oxidation activity and resistance to carbon formation for chemical-looping steam methane reforming (CL-SMR) were investigated. The desired crystalline perovskite phases were formed by transferring from the orthorhombic structure of LaFeO3 to rhombohedral lattice of LaMnO3 as the degree of Mn-doping increased. Manganese ions have a mixed state of Mn3+ and Mn4+ in the LaFe1−xMnxO3, meanwhile inducing the states of highly mixed character of Fe2+, Fe3+ and Fe4+ in iron ions. Substitution of Mn for Fe with proper value not only increases the lattice oxygen, which is conducive to the partial oxidation of CH4 to produce syngas, but also enhances the lattice oxygen mobility from the bulk to the surface of the oxygen carrier particles. Judging from the points of the redox reactivity, resistance to carbon formation and hydrogen generation capacity, the optimal range of the degree of Mn substitution is x=0.3-0.5.

The Constituents Isolated from Peucedanum japonicum Thunb. and their Cyclooxygenase (COX) Inhibitory Activity

Zheng, Mingshan,Jin, Wenyi,Son, Kun-Ho,Chang, Hyeun-Wook,Kim, Hyun-Pyo,Bae, Ki-Hwan,Kang, Sam-Sik The Korean Society of Medicinal Crop Science 2005 한국약용작물학회지 Vol.13 No.2

Five coumarins, psoralen (1), scopoletin (2), isoimperatorin (4), (+)-marmesin (5) and xanthotoxin (6), three chromones, cimifugin (3), hamaudol (7) and sec-O-glucosylhamaudol (10), one sterol, daucosterol (8) and one aliphatic alcohol, galactitol (9) were isolated from the root of Peucedanum japonicum. Their chemical structures were identified by the physicochemical and spectroscopic data by comparing literature values. Among them, compounds 9 and 10 were isolated for the first time from this plant. The anti-inflammatory effects of isolated compounds were examined on cyclooxygenase (COX), compounds 1, 2 and 7 showed inhibitory activity on COX-1 with $IC_{50}$ values of 0.88, 0.27 and 0.30 mM, respectively. In the test for COX-2 activity, only compound 7 showed significant inhibitory activity with the $IC_{50}$ value of 0.57 mM. The other compounds exhibited weak inhibitory or no inhibitory activity.

Novel Determination of Wheel-Rail Adhesion Stability for Electric Locomotives

Kun Xu,Guoqing Xu,Chunhua Zheng 한국정밀공학회 2015 International Journal of Precision Engineering and Vol. No.

Monitoring the wheel-rail adhesion state and maintaining the stability are the key issues to ensure the safety of locomotives withincreasing running speed nowadays. In this paper, a novel methodology is proposed to determine the wheel-rail adhesion stability. It is proved that when the adhesion state is in the unstable region, the transmitting factor which is defined as the ratio of the adhesionforce in the wheel drive force is negative. Based on this principle, we propose a novel adhesion stability detector via measuring thewheel drive torque and the wheel rotational speed. It is free from measuring or determining the chassis speed, creep ratio, and optimalcreep ratio, which are usually difficult to obtain in practical applications. In addition, the proposed methodology can evaluate theadhesion state dynamically regardless of the specific wheel-rail conditions. Numerical simulations are carried out to validate itseffectiveness.

Analysis of Fracture Surface Morphology and Study of Seepage Diffusion Characteristics

Zheng Li,Kun Mao,Jie Liu,Kexin Zhang 대한토목학회 2024 KSCE Journal of Civil Engineering Vol.28 No.1

There are a large number of rough and irregular fractures in underground engineering rock mass, which makes the movement of fracture fluid very complex. To address the issues of non-visibility of physical model tests and non-repeatability of joint surfaces in natural rock fractures, a method was proposed to accurately depict the impact of rough fracture morphology on rock seepage. This method involved using natural rock fractures as a prototype and creating secondary molds using gypsum and silica gel to precisely replicate the rough fracture surface morphology. The three-dimensional morphology scanning technology was used to accurately obtain the surface morphology information of rough fractures, and the anisotropy of rough fracture morphology parameters was analyzed. Additionally, the study investigated the characteristics of seepage area and frontal flow line morphology through the use of a visual transparent fracture model. The obtained results provided an intuitive understanding of the distribution law of the seepage field. The evolution law of flow velocity with roughness was analyzed by layer superposition technique. The point of maximum flow velocity corresponded to the point of abrupt change in elevation, which occurred in the region with the greatest fluctuation height of the fracture surface. The accurate description of flow patterns in various rough fractures offers theoretical guidance for seepage in rock fractures in practical engineering applications.

Photoluminescence from SiGe NPs: SiO_2 Thin Films Co-doped with Al

Kun Zhong,Guoan Cheng,Xiangqian Cheng,Ruiting Zheng,Zhisong Xiao 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.58 No.41

Different doses of Al atoms were implanted into SiGe-rich SiO2 thin films, and the impacts of the doping dose and the annealing temperature on the photoluminescence (PL) from these thin films were investigated. Al-doping promoted the nucleation of SiGe nanoparticles (NPs). The addition of Al enhanced the PL intensity owing to an increase in the number of nucleation sites. However, the Al impurity generated a deep recombination level in the band gap of the SiGe NPs. When the Al-doping dose was 6 X 10^(14) cm^(−2), the intensity of the PL reached a maximum.