Efficient biosorption of Pb(II) from aqueous solutions by a PAH-degrading strain Herbaspirillum chlorophenolicum FA1

Xiaohui Li,Hongxia Xu,Bin Gao,Xiaoqing Shi,Yuanyuan Sun,Jichun Wu 한국공업화학회 2018 Journal of Industrial and Engineering Chemistry Vol.57 No.-

For the first time, biosorption of lead(II) using a PAHs-degrading bacterium, Herbaspirillum chlorophenolicum FA1, was investigated as a function of initial lead concentration, biomass dosage, pH, and temperature in batch conditions. Results showed that FA1 was highly resistant to lead and grew well even at lead concentration of 200 mg L−1. The kinetic and isotherm data were well described by commonly used models, such as the pseudo-second-order and Langmuir models. Adsorption thermodynamics was spontaneous and endothermic, and FA1 exhibited a high sorption capacity of 151.52 mg g−1. SEM-EDS and FTIR analysis was conducted to further explore the interaction mechanisms.

Impacts of the side ratio of isolated buildings on airflows and pollutant dispersion under different temperature stratifications: Numerical investigations

Xiaohui Huang,Lizhen Gao 대한환경공학회 2022 Environmental Engineering Research Vol.27 No.4

Based on the Reynolds-averaged Navier-Stokes (RANS) method, the standard k-ε turbulence model was used to simulate the effects of the side ratio (SR: building depth/building width, SR = 0.5, 1.0, 1.5, and 2.0, respectively) of isolated buildings on the flow field and pollutant of ethylene dispersion under unstable temperature stratification and neutral conditions. The results showed that under unstable temperature stratification, the updraft on the leeward side of the building caused the high temperature gas to flow upward and the temperature gradient to drop. Compared with the neutral condition, the length of the recirculation zone was shorter, and with the decrease in SR, the vortex in the recirculation zone became larger and more stable. Because the pollution source was located on the leeward side of the building, the pollutant gas was concentrated in the area between the pollution source and the leeward side of the building. The near-ground concentration of pollutants under unstable temperature stratification was lower than that under neutral conditions, and with the decrease in SR, the near-ground axis concentration decreased while the width of the pollutant plumes increased.

Evaluation of AF type cyclic plasticity models in ratcheting simulation of pressurized elbow pipes under reversed bending

Xiaohui Chen,Bingjun Gao,Xu Chen 국제구조공학회 2016 Steel and Composite Structures, An International J Vol.21 No.4

The ratcheting behavior was studied experimentally for Z2CND18.12N elbow piping under cyclic bending and steady internal pressure. Dozens of cyclic plasticity models for structural ratcheting responses simulations were used in the paper. The four models, namely, Bilinear (BKH), Multilinear (MKIN/KINH), Chaboche (CH3), were already available in the ANSYS finite element package. Advanced cyclic plasticity models, such as, modified Chaboche (CH4), Ohno-Wang, modified Ohno-Wang, Abdel Karim-Ohno and modified Abdel Karim-Ohno, were implemented into ANSYS for simulating the experimental responses. Results from the experimental and simulation studies were presented in order to demonstrate the state of structural ratcheting response simulation by these models. None of the models evaluated perform satisfactorily in simulating circumferential strain ratcheting response. Further, improvement in cyclic plasticity modeling and incorporation of material and structural features, like time-dependent, temperature-dependent, non-proportional, dynamic strain aging, residual stresses and anisotropy of materials in the analysis would be essential for advancement of low-cycle fatigue simulations of structures.

Evaluation of limit load analysis for pressure vessels ‒ Part I: Linear and nonlinear methods

Xiaohui Chen,Bingjun Gao,Xingang Wang 국제구조공학회 2016 Steel and Composite Structures, An International J Vol.22 No.6

Limit load of pressure bearing structures was reviewed in this article. By means of the finite element analysis, limit load of pressurized cylinder with nozzle was taken as an example. Stress classification method and Elastic-plastic finite element analysis combining with limit load determination methods were used to determine limit load of cylinder with nozzle. Comparison of limit load determined by different methods, the results indicated that limit load determined by linearization method was the smallest. Limit load determined by twice elastic slope criterion was the nearest than experimental results. Elastic-plastic finite element analysis had comparably computational precision, but required time consuming. And then the requirements of computer processing and storage capacity by power system became higher and higher. Most of criteria for limit load estimation included any human factors based on a certain substantive characteristics of experimental results. The reasonable criterion should be objective and operational.

Evaluation of limit load analysis for pressure vessels — Part II: Robust methods

Xiaohui Chen,Bingjun Gao,Xingang Wang 국제구조공학회 2017 Steel and Composite Structures, An International J Vol.23 No.1

Determining limit load for a pressure bearing structure using elastic-plastic finite element analysis was computationally very expensive. A series of robust methods using elastic modulus adjustment techniques (EMAP) to identify the limit load directly were proposed. The numerical implementation of the robust method had the potential to be an attractive alternative to elastic-plastic finite element analysis since it was simple, and required less computational effort and computer storage space. Another attractive feature was that the method provided a go/no go criterion for the limit load, whereas the results of an elastic-plastic analysis were often difficult to interpret near the limit load since it came from human sources. To explore the performance of the method further, it was applied to a number of configurations that include two-dimensional and threedimensional effects. In this study, limit load of cylinder with nozzle was determined by the robust methods.

Web-based Visualization and Analysis of Atmospheric Nucleation Processes

Jinzhu Gao,Rui Ding,Yi Liu,Bin Chen,Xiaohui Cui,J. Ilja Siepman 보안공학연구지원센터(IJUNESST) 2009 International Journal of u- and e- Service, Scienc Vol.2 No.2

Experimental research on local buckling of BS700 high-strength steel thin-walled box-section members under axial compression

Lei Gao,Fei Shao,Linyue Bai,Xingkun Xie,Xiaohui He 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.5

In this study, the ultimate bearing capacity and local buckling failure mode of members were investigated, and the results were compared to the predicted values of the existing steel structures design code. The results indicated that the failure mode of the specimen was local buckling. Finite element model is verified using experimental results. FE model is capable of predicting the behaviour of specimens and it is used for further numerical analyses. Experimental results are compared with recommendations of the steel structures design code of GB50017-2017, ANSI/AISC 360-16 and Eurocode 3. It is observed that the 83.3 % of the test bearing capacity are slightly higher than the predictions of existing codes with a variance of 5 %. It is concluded that the provisions of existing codes can meet the design requirements. However, the number of tests is limited and further related experimental and FE numerical studies are required.

Sensitive parameters’ optimization of the permanent magnet supporting mechanism

Yongguang Liu,Xiaohui Gao,Yixuan Wang,Xiaowei Yang 대한기계학회 2014 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.28 No.7

The fast development of the ultra-high speed vertical rotor promotes the study and exploration for the supporting mechanism. It hasbecome the focus of research that how to improve the speed and overcome the vibration when the rotors pass through the low-order criticalfrequencies. This paper introduces a kind of permanent magnet (PM) supporting mechanism and describes an optimization method ofits sensitive parameters, which can make the vertical rotor system reach 80000 r/min smoothly. Firstly we find the sensitive parametersthrough analyzing the rotor’s features in the process of achieving high-speed, then, study these sensitive parameters and summarize theregularities with the method of combining the experiment and the finite element method (FEM), at last, achieve the optimization methodof these parameters. That will not only get a stable effect of raising speed and shorten the debugging time greatly, but also promote theextensive application of the PM supporting mechanism in the ultra-high speed vertical rotors.

A Multi-objective Planning of Transmission Line Balance Degree Based on Power Flow Entropy Theory

Jiaqing Zhong,Fanfan Gao,Xiaohui Zhang 대한전기학회 2022 Journal of Electrical Engineering & Technology Vol.17 No.5

The equilibrium degree of transmission lines in the multi-objective planning of power grid is studied in this paper. The main purpose of the study is to ensure the economy and improve the balanced distribution of active power fl ow of transmission lines, furthermore increase the adaptability of transmission lines in the future power grid. The problem is mainly focus on the single-level of line load rate, in researching on the distribution balance of active power fl ow in transmission lines. Three indexed, which are line load rate power fl ow entropy, active loss rate power fl ow entropy and transmission effi ciency power fl ow entropy, are defi ned in this paper. The weighted sum of the three indexes is defi ned as the balance factor of active power fl ow distribution in transmission lines. This factor is used in transmission network planning to improve the overall balance of active power fl ow distribution in transmission lines. On this basis, a multi-objective programming model with minimum economic cost and maximum equilibrium factor of transmission network is established. The model is solved by using multiobjective bacterial colony chemotactic algorithm (BCC) and optimal compromise solution method. The results verify the superiority and rationality of the proposed method and model.

Hippo signaling is intrinsically regulated during cell cycle progression by APC/C^Cdh1

Kim, Wantae,Cho, Yong Suk,Wang, Xiaohui,Park, Ogyi,Ma, Xueyan,Kim, Hanjun,Gan, Wenjian,Jho, Eek-hoon,Cha, Boksik,Jeung, Yun-ji,Zhang, Lei,Gao, Bin,Wei, Wenyi,Jiang, Jin,Chung, Kyung-Sook,Yang, Yingzi National Academy of Sciences 2019 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF Vol.116 No.19

<P><B>Significance</B></P><P>The Hippo signaling pathway is evolutionarily conserved in the animal kingdom and plays essential roles in regulating tissue growth during development and regeneration. We have identified APC/C<SUP>Cdh1</SUP>, a core component of cell cycle control machinery, as an evolutionarily conserved and previously unknown regulator of large tumor suppressor (LATS) kinases, which critically inhibit the YAP/TAZ transcription factors in transducing Hippo signaling. Our results suggest a model that APC/C<SUP>Cdh1</SUP> destabilizes LATS1/2 kinases in G1 phase of the cell cycle, leading to increased YAP/TAZ activities that promote G1/S transition by upregulating downstream gene expression, including <I>E2F1</I>. Our findings have important implications for a link between cell proliferation and LATS-regulated YAP/TAZ activities.</P><P>The Hippo-YAP/TAZ signaling pathway plays a pivotal role in growth control during development and regeneration and its dysregulation is widely implicated in various cancers. To further understand the cellular and molecular mechanisms underlying Hippo signaling regulation, we have found that activities of core Hippo signaling components, large tumor suppressor (LATS) kinases and YAP/TAZ transcription factors, oscillate during mitotic cell cycle. We further identified that the anaphase-promoting complex/cyclosome (APC/C)<SUP>Cdh1</SUP> E3 ubiquitin ligase complex, which plays a key role governing eukaryotic cell cycle progression, intrinsically regulates Hippo signaling activities. CDH1 recognizes LATS kinases to promote their degradation and, hence, YAP/TAZ regulation by LATS phosphorylation is under cell cycle control. As a result, YAP/TAZ activities peak in G1 phase. Furthermore, we show in <I>Drosophila</I> eye and wing development that Cdh1 is required in vivo to regulate the LATS homolog Warts with a conserved mechanism. Cdh1 reduction increased Warts levels, which resulted in reduction of the eye and wing sizes in a Yorkie dependent manner. Therefore, LATS degradation by APC/C<SUP>Cdh1</SUP> represents a previously unappreciated and evolutionarily conserved layer of Hippo signaling regulation.</P>