Experimental comparability between steam and normal curing methods on tensile behavior of RPC

Guo, Min,Gao, Ri Techno-Press 2021 Advances in concrete construction Vol.11 No.4

To address the limitation of the commonly used steam curing of reactive powder concrete (SC-RPC) in engineering, a preparation technology of normal curing reactive powder concrete (NC-RPC) is proposed. In this study, an experimental comparative research on the mechanical properties of NC-RPC and SC-RPC under uniaxial tension is conducted. Under the premise of giving full play to the ultra-high performance of RPC, the paper tries to explore whether normal curing can replace steam curing. The results show that various mechanical indexes of NC-RPC (e.g., tensile strength, ultimate tensile strain, elastic modulus and deformation performance) could basically reach the mechanical index values in steam curing at 28d age, some performance is even better at a longer age. So it affirms the feasibility of normal curing. In this paper, the influence of normal curing age on the tensile properties of RPC is discussed, and the relationship between each index and age is introduced in detail. Based on the experimental data, the tensile mechanism of RPC is analyzed theoretically, and two kinds of tensile constitutive models for RPC are proposed, one is curvilinear model, and another one is polygonal line model. The validity of the two models is further verified by the test results of others.

Concurrent Relay-PID Control for Motor Position Servo Systems

Guomin Li,Kai Ming Tsang 대한전기학회 2007 International Journal of Control, Automation, and Vol.5 No.3

A Concurrent Relay-PID controller (CRPID) for motor position servo systems is proposed in this paper. The proposed controller is composed of a deadband-relay subcontroller and a parallel PID subcontroller. The deadband-relay subcontroller is capable of improving the transient system performance while the PID subcontroller is responsible for near steady state system regulation. Systematic design methods for various controller components are developed. Design procedures are illustrated by an example. The proposed hybrid scheme is applied to a DC motor position servo system. Both numerical and experimental results demonstrate that the proposed controller performs satisfactorily and is superior to PID control alone.

An efficient Agrobacterium-mediated transformation method for aflatoxin generation fungus Aspergillus flavus

Guomin Han,Qian Shao,Cuiping Li,Kai Zhao,Li Jiang,Jun Fan,Haiyang Jiang,Fang Tao 한국미생물학회 2018 The journal of microbiology Vol.56 No.5

Aspergillus flavus often invade many important corps and produce harmful aflatoxins both in preharvest and during storage stages. The regulation mechanism of aflatoxin biosynthesis in this fungus has not been well explored mainly due to the lack of an efficient transformation method for constructing a genome-wide gene mutant library. This challenge was resolved in this study, where a reliable and efficient Agrobacterium tumefaciens-mediated transformation (ATMT) protocol for A. flavus NRRL 3357 was established. The results showed that removal of multinucleate conidia, to collect a homogenous sample of uninucleate conidia for use as the transformation material, is the key step in this procedure. A. tumefaciens strain AGL-1 harboring the ble gene for zeocin resistance under the control of the gpdA promoter from A. nidulans is suitable for genetic transformation of this fungus. We successfully generated A. flavus transformants with an efficiency of ~ 60 positive transformants per 106 conidia using our protocol. A small-scale insertional mutant library (~ 1,000 mutants) was constructed using this method and the resulting several mutants lacked both production of conidia and aflatoxin biosynthesis capacity. Southern blotting analysis demonstrated that the majority of the transformants contained a single T-DNA insert on the genome. To the best of our knowledge, this is the first report of genetic transformation of A. flavus via ATMT and our protocol provides an effective tool for construction of genome-wide gene mutant libraries for functional analysis of important genes in A. flavus.

Isolation and Evaluation of Terrestrial Fungi with Algicidal Ability from Zijin Mountain, Nanjing, China

Guomin Han,Xiaoguang Feng,Yong Jia,Congyan Wang,Xingbing He,Qiyou Zhou,Xingjun Tian 한국미생물학회 2011 The journal of microbiology Vol.49 No.4

Approximately 60 fungal isolates from Zijin Mountain (Nanjing, China) were screened to determine their algicidal ability. The results show that 8 fungi belonging to Ascomycota and 5 belonging to Basidiomycota have algicidal ability. Of these fungi, Irpex lacteus T2b, Trametes hirsuta T24, Trametes versicolor F21a,and Bjerkandera adusta T1 showed strong algicidal ability. The order of fungal chlorophyll-a removal efficiency was as follows: T. versicolor F21a > I. lacteus T2b > B. adusta T1 > T. hirsuta T24. In particular, T. versicolor F21a completely removed algal cells within 30 h, showing the strongest algicidal ability. The results also show that all 4 fungal species degraded algal cells through direct attack. In addition, most of the tested fungi from the order Polyporales of Basidiomycota exhibited strong algicidal activity, suggesting that most fungi that belong to this order have algicidal ability. The findings of this work could direct the search for terrestrial fungi for bloom control.

Rapid Developing China's Market

Luo Guomin,Yang Hejiun 한국전략마케팅학회 1994 마케팅논집 Vol.4 No.1

Selective hydrogenation of furfural to cyclopentanone over Cu-Ni-Al hydrotalcite-based catalysts

Hongyan Zhu,Guomin Xiao,Minghao Zhou,Zuo Zeng,Rui Xiao 한국화학공학회 2014 Korean Journal of Chemical Engineering Vol.31 No.4

A series of Cu-Ni-Al hydrotalcites derived oxides with a (Cu+Ni)/Al mole ratio of 3 with varied Cu/Nimole ratio (from 0.017 to 0.5, with a Cu ratio of 0.0125 to 0.25) were prepared by co-precipitation method, then appliedto the hydrogenation of furfural in aqueous. Their catalytic performance for liquid phase hydrogenation of furfural toprepare cyclopentanone was described in detail, considering reaction temperature, catalyst composition, reaction timeand so on. The yield of cyclopentanone was influenced by the mole ratio of Cu-Ni-Al based heterogeneous catalystand depended on the reaction conditions. The yield of cyclopentanone was up to 95.8% when the reaction was carriedout under 413 K with H2 pressure of 40 bar for 8 h. The catalysts were characterized by X-ray powder diffraction (XRD),scanning electron microscope (SEM) and H2 temperature-programmed reduction (H2-TPR).

Synthesis and Structure Properties of Flame Retardant and Cationic Dyeable Polyamide 6 Modified with 5-sulfoisophthalic Acid Sodium and Melamine Cyanurate

Yifan Fu,Yun Teng,Guomin Yu,Cuiyu Yin 한국섬유공학회 2018 Fibers and polymers Vol.19 No.7

Unmodified polyamide 6 commonly dyed with acid dyes, and has no flame-retarded properties. So they are flammable and can be easily stained by foods or drinks that contain acid dyes. However, the acid groups react with amino groups that existed at the end of PA6 chain while using cationic dyes. Thus, the acid dyes can be washed immediately. In this study, the flame retardant and cationic dyeable polyamide 6 (FRCD-PA6) modified with 5-sulfoisophthalic acid sodium (5- SSIPA) and melamine cyanurate (MCA) was successfully prepared by the two-step-melt polymerization method. Firstly, cationic dyeable polyamide 6 (CD-PA6) was prepared with sodium salt from 5-sulfoisphthalic acid. Secondly, melamine cyanurate, as an efficient flame retardant, was blended into the reaction. The chemical and crystalline structures of FRCDPA6 were characterized by the Fourier transform infrared spectroscopy (FT-IR) and wide angle X-ray diffraction (XRD). Their thermal properties were tested by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), and morphology was analyzed by SEM, respectively. It had been measured to prove the dispersion of 5-SSIPA and MCA on polyamide 6 matrix. Incorporating with 5-SSIPA created more amorphous regions and rose up the dyeing rate easily, with a highest dyeing rate for about 96.79 %. The effect of varying MCA content on the composites showed more flame retardant and made better heat-resistance. Moreover, with the appropriate addition of MCA content, the limit oxygen index (LOI) reached up to 27, less smoking, no more black smoke, droplet phenomenon was slightly, and flame resistance had greatly improved. Because of the good synergy between 5-SSIPA and MCA, a kind of novel modified polyamide 6 which own both cationic dyeable and efficient flame retardant properties was born.

Study on the Effect of Tween80 on the Properties of PVA/SCFs Composites

Liulan Lin,Weixuan Xu,Guomin Liu 한국고분자학회 2023 폴리머 Vol.47 No.5

An intelligent optimization method for the HCSB blanket based on an improved multi-objective NSGA-III algorithm and an adaptive BP neural network

Zhou Wen,Sun Guomin,Miwa Shuichiro,Yang Zihui,Li Zhuang,Zhang Di,Wang Jianye 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.9

To improve the performance of blanket: maximizing the tritium breeding rate (TBR) for tritium selfsufficiency, and minimizing the Dose of backplate for radiation protection, most previous studies are based on manual corrections to adjust the blanket structure to achieve optimization design, but it is difficult to find an optimal structure and tends to be trapped by local optimizations as it involves multiphysics field design, which is also inefficient and time-consuming process. The artificial intelligence (AI) maybe is a potential method for the optimization design of the blanket. So, this paper aims to develop an intelligent optimization method based on an improved multi-objective NSGA-III algorithm and an adaptive BP neural network to solve these problems mentioned above. This method has been applied on optimizing the radial arrangement of a conceptual design of CFETR HCSB blanket. Finally, a series of optimal radial arrangements are obtained under the constraints that the temperature of each component of the blanket does not exceed the limit and the radial length remains unchanged, the efficiency of the blanket optimization design is significantly improved. This study will provide a clue and inspiration for the application of artificial intelligence technology in the optimization design of blanket.

Constructing polyurethane foams of strong mechanical property and thermostability by two novel environment friendly bio-based polyols

Zhenwu Kong,Shuping Huo,Guomin Wu,Jian Chen,Guifeng Liu 한국화학공학회 2016 Korean Journal of Chemical Engineering Vol.33 No.3

Two novel cardanol-based polyols were synthesized and used to construct polyurethane (PU) foams. The cardanol-based polyols with high reactivity were obtained from the epoxidation of cardanol, followed by the ring opening reaction of epoxy group with diethanolamine (DEA). Subsequently, PU foams were synthesized by these cardanolbased polyols. Compared with petroleum-based (PEG) PU foams, these green cardanol-based PU foams exhibit better mechanical property and higher thermostability. Scanning electron microscopy (SEM) tests show that the cells of cardanol- based PU foams are monodisperse, with fairly uniform spherical shape and regular size.