Dynamic balancing of multispeed multidisk rotor

Yulin Guo,Jianfei Yao,Yan Li 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.5

This study proposes a method to balance the multidisk rotor systems of aeroengines. A double screening-based correction plane selection method with constraints, such as balancing effect and trim weight, is proposed in this work. The first screening takes the balance effect of the rotor system as the objective function, and the scheme of the correction planes with the better balance effect is selected in the first screening. The second screening aims to screen the trim weight that satisfies the constraints. The scheme of the optimal trim plane is obtained with the balancing effect coefficients of the unit trim weight. The double optimization method is utilized for the multidisk rotor in the simulation and experiment. Results show that the proposed method can suppress the vibration of multidisk rotors working at high speeds.

Effect of Sodium Tripolyphosphate on Clay Tolerance of Polycarboxylate Superplasticizer

Hongbo Tan,Yulin Guo,Baoguo Ma,Jian Huang,Benqing Gu,Fubing Zou 대한토목학회 2018 KSCE JOURNAL OF CIVIL ENGINEERING Vol.22 No.8

High fluidity concrete has been widely used in modern civil engineering project to ensure that the highly efficient construction process canbe achieved. Generally, the fluidity can be obtained with the incorporation of superplasticizer system composed of polymers and retarders. Sodium tripolyphosphate (STPP), a commonly used retarder in cement-based material, can obviously increase the dispersion ofpolycarboxylate superplasticizer (PCE), and this has been widely employed in real concrete. However, the effect of STPP on clay toleranceof PCE has not been confirmed until now, and it is still uncertain whether STPP in PCE system has positive or negative effect on workabilityof fresh concrete with poor-quality aggregates containing montmorillonite (Mt) which is one of the most harmful clay minerals. In this study,the effect of STPP on fluidity of cement-Mt paste with PCE has been investigated. The fluidity was tested with mini slump to assess the claytolerance of PCE. The adsorption amount of PCE and STPP in Mt suspension was tested with total organic carbon analyzer and inductivecoupled plasma emission spectrometer to characterize the adsorption behavior. The interlayer spacing was evaluated with X-rayDiffractometer and the structure of intercalated Mt by PCE was characterized with Fourier-transform infrared spectrometer and thermogravimetric analyzer, and these results were used to illustrate the effect of STPP on intercalation of PCE. Finally, the dispersion model wasproposed to reveal the mechanism behind. The results show that STPP can disperse the Mt particles and increase adsorption amount of PCEin Mt suspension, thereby accelerating rather than hindering the intercalation of PCE into Mt. The fluidity of cement-Mt paste with PCESTPPsystem is depended on the added dosage of STPP: with the dosage less than 0.20%, the contribution of STPP to dispersing the cementparticles predominates, hence increasing the fluidity of the paste and improving the clay tolerance; while with the dosage more than 0.20%,the acceleration of the intercalation of PCE resulting from STPP becomes predominant, thereby reducing the fluidity of the paste. This resultcan provide useful experience for the improvement in clay tolerance of PCE in real concrete with poor aggregate containing Mt.

Modification of hollow BiOCl/TiO2 nanotubes with phosphoric acid to enhance their photocatalytic performance

Guozhe Sui,Yulin Zhang,Jinlong Li,Yan Zhuang,Dongxuan Guo,Ze Luo,Rongping Xu,Shuang Liang,Hong Yao,Chao Wang 한국화학공학회 2022 Korean Journal of Chemical Engineering Vol.39 No.4

Organic pollutants in dyed wastewater are hazardous to human health and the environment. The photocatalyticdegradation of pollutants is considered a green treatment with significant social and environmental benefits. Inthis study, hollow BiOCl/TiO2 nanotubes with open pores at both ends, prepared by hydrothermal synthesis, weremodified using phosphoric acid to promote photoelectron transfer. The hollow nanotubes offer an increased numberof electroactive sites, which enhances the photoelectric transfer efficiency and reduces the electron-hole recombinationrate. The modification by H3PO4 significantly optimized the photocatalytic activity of the nanotubes. The results showthat the H3PO4 modified hollow BiOCl/TiO2 (molar ratio of BiOCl to TiO2 is 0.8) nanotubes exhibited the most efficientphotocatalytic performance toward rhodamine B (RhB) with a photodegradation efficiency of up to 98.8% undervisible-light illumination. These nanotubes have broad application prospects for the effective removal of organic pollutantsfrom wastewater and can potentially inform future research on photocatalysts.

Effect of sodium gluconate on dispersion of polycarboxylate superplasticizer with different grafting density in side chain

Fubing Zou,Hongbo Tan,Yulin Guo,Baoguo Ma,Xingyang He,Yang Zhou 한국공업화학회 2017 Journal of Industrial and Engineering Chemistry Vol.55 No.-

Sodium gluconate is a commonly used retarder, and the incorporation of SG has been accepted as the most efficient way to improve the basic performance of polycarboxylate superplasticizer (PCE) system in real concrete. However, this improvement cannot be always achieved, and the main reason for this uncertainty is because the interaction between PCE and SG has not completely understood. In order to gain deeper insight into this interaction, adsorption behavior and dispersion mechanism of PCE-SG system involved in two kinds of PCE with different grafting density of carboxyl groups in side chain have been investigated. Specifically, the dispersion was assessed with the fluidity of the cement paste, and adsorption behavior was estimated with total organic carbon and zeta potential. The combination between PCE and SG was characterized with conductivity, dynamic light scattering, and X-ray photoelectron spectroscopy. Finally, several models were proposed to illustrate the mechanism behind. The results show that gluconate grafted as side chain of PCE and the increase in length of PEO chain caused by addition of SG can provide contribution to dispersion. Competitive adsorption between SG and PCE would take place to reduce the dispersion, and the declining degree depends on the relative adsorption between PCE and SG. Dispersion of PCE-SG is not only dependent on added dosage of SG, but also decided by molecular structure of PCE. This result provides guidance on how to promote the basic performance of the PCE-retarder system in real engineering practice.

Molecular mapping of four blast resistance genes using recombinant inbred lines of 93-11 and nipponbare

Hongmei Yang,Melissa H Jia,Yulin Jia,Junjie Xing,Venu, R-C,Maria Bellizzi,Longping Yuan,Zhilong Wang,Chuanqing Sun,Guo-Liang Wang 한국식물학회 2013 Journal of Plant Biology Vol.56 No.2

Molecular mapping of new blast resistance genes is important for developing resistant rice cultivars using marker-assisted selection. In this study, 259 recombinant inbred lines (RILs) were developed from a cross between Nipponbare and 93-11, and were used to construct a 1165.8-cM linkage map with 131 polymorphic simple sequence repeat (SSR) markers. Four major quantitative trait loci (QTLs) for resistance to six isolates of Magnaporthe oryzae were identified: qPi93-1, qPi93-2, qPi93-3, and qPiN-1. For the three genes identified in 93-11, qPi93-1 is linked with SSR marker RM116 on the short arm of chromosome 11 and explains 33% of the phenotypic variation in resistance to isolate CHE86. qPi93-2 is linked with SSR marker RM224 on the long arm of chromosome 11 and accounts for 31% and 25% of the phenotypic variation in resistance to isolates 162-8B and ARB50, respectively. qPi93-3 is linked with SSR marker RM7102 on chromosome 12 and explains 16%, 53%, and 28% of the phenotypic variation in resistance to isolates CHE86, ARB52, and ARB94, respectively. QTL qPiN-1 from Nipponbare is associated with SSR marker RM302 on chromosome 1 and accounts for 34% of the phenotypic variation in resistance to isolate PO6-6. These new genes can be used to develop new varieties with blast resistance via marker-aided selection and to explore the molecular mechanism of rice blast resistance.

Deep transcriptome sequencing reveals the expression of key functional and regulatory genes involved in the abiotic stress signaling pathways in rice

R.C. Venu,M.V. Sreerekha,M. Sheshu Madhav,Kan Nobuta,K. Madhan Mohan,Songbiao Chen,Yulin Jia,Blake C. Meyers,Guo-Liang Wang 한국식물학회 2013 Journal of Plant Biology Vol.56 No.4

Drought, salt and cold are the major abiotic stresses that limit the rice production. Identification of the key functional and regulatory genes in the abiotic stress signaling pathways is important for understanding the molecular basis of abiotic stress tolerance. In this study, we investigated the transcriptomes of rice leaves and roots under cold, drought, and salt stresses using the massively parallel signature sequencing (MPSS) and sequencing by synthesis (SBS) technologies. About 1.8 to 2.6 million individual signatures were obtained from the seven abiotic-stressed and control libraries of the japonica cultivar Nipponbare. A total of 102,630 and 1,414,788 distinct signatures were obtained from the MPSS and SBS libraries, respectively. Clustering analysis identified many up- and down-regulated genes specifically and commonly expressed in the cold, drought and salt-treated plant leaves and roots. Data mining revealed the expression patterns of key functional and regulatory genes that were involved in different abiotic stress signaling pathways. Highly conserved cis-regulatory elements in the promoter of the up-regulated genes were identified. Our comprehensive and deep survey of abiotic stress transcriptome of rice has provided candidate genes for further understanding the molecular basis of abiotic stress tolerance in rice.