• Title/Summary/Keyword: Tianjin

Search Result 601, Processing Time 0.03 seconds

Studies on T-Shaped composite columns consist of multi separate concrete-filled square tubular steel sections under eccentric axial load

  • Rong, Bin;You, Guangchao;Zhang, Ruoyu;Feng, Changxi;Liu, Rui
    • Steel and Composite Structures
    • /
    • v.22 no.2
    • /
    • pp.217-234
    • /
    • 2016
  • In order to investigate mechanical properties and load-bearing capacity of T-shaped Concrete-Filled Square Steel Tubular (TCFST) composite columns under eccentric axial load, three T-shaped composite columns were tested under eccentric compression. Experimental results show that failure mode of the columns under eccentric compression was bending buckling of the whole specimen, and mono column performs flexural buckling. Specimens behaved good ductility and load-bearing capacity. Nonlinear finite element analysis was also employed in this investigation. The failure mode, the load-displacement curve and the ultimate bearing capacity of the finite element analysis are in good agreement with the experimental ones. Based on eccentric compression test and parametric finite element analysis, the calculation formula for the equivalent slenderness ratio was proposed and the bearing capacity of TCFST composite columns under eccentric compression was calculated. Results of theoretical calculation, parametric finite element analysis and eccentric compression experiment accord well with each other, which indicates that the theoretical calculation method of the bearing capacity is advisable.

Synthesis of Molecularly Imprinted Polymers for Chiral (S)-Ibuprofen and Their Molecular Recognition Mechanism (키랄(S)-이부푸로펜 함유 고분자의 합성과 제조된 고분자의 분자 인식 메카니즘)

  • Huangfu, Fengyun;Wang, Bing;Sun, Yan
    • Polymer(Korea)
    • /
    • v.37 no.3
    • /
    • pp.288-293
    • /
    • 2013
  • A group of molecularly imprinted polymers (MIPs) with specific recognition for chiral (S)-ibuprofen were successfully prepared based on hydrogen bonds, utilizing ${\alpha}$-methacrylic acid as a functional monomer. The IR analysis of MIPs showed that the blue- and red-shifted hydrogen bonds were formed between templates and functional monomers in the process of self-assembly imprinting and re-recognition, respectively. According to UV-Vis analysis, we found that the ratio of host-guest complexes between template molecule and functional monomer was 1:1. The effect of cross-linker's quantity on the polymerization was studied by transmission electron microscope (TEM). The adsorption selectivity experiments indicated that MIPs exhibited higher selectivity to (S)-ibuprofen than those to ketoprofen and (R)-ibuprofen, (S)-ibuprofen's structural analogs.

Field instrumentation and settlement prediction of ground treated with straight-line vacuum preloading

  • Lei, Huayang;Feng, Shuangxi;Wang, Lei;Jin, Yawei
    • Geomechanics and Engineering
    • /
    • v.19 no.5
    • /
    • pp.447-462
    • /
    • 2019
  • The vacuum preloading method has been used in many countries for ground improvement and land reclamation works. A sand cushion is required as a horizontal drainage channel for conventional vacuum preloading. In terms of the dredged-fill foundation soil, the treatment effect of the conventional vacuum preloading method is poor, particularly in Tianjin, China, where a shortage of sand exists. To solve this problem, straight-line vacuum preloading without sand is widely adopted in engineering practice to improve the foundation soil. Based on the engineering properties of dredged fill in Lingang City, Tianjin, this paper presents field instrumentation in five sections and analyzes the effect of a prefabricated vertical drain (PVD) layout and a vacuum pumping method on the soft soil ground treatment. Through the arrangement of pore water pressure gauges, settlement marks and vane shear tests, the settlement, pore water pressure and subsoil bearing capacity are analyzed to evaluate the effect of the ground treatment. This study demonstrates that straight-line vacuum preloading without sand can be suitable for areas with a high water content. Furthermore, the consolidation settlement and consolidation degree system is developed based on the grey model to predict the consolidation settlement and consolidation degree under vacuum preloading; the validity of the system is also verified.

A Study on Strengthening Competitiveness for China TianJin Port (중국 천진항의 경쟁력 강화 방안에 관한 연구)

  • Song, Xiaoming;Shin, Han-Won
    • Journal of Fisheries and Marine Sciences Education
    • /
    • v.26 no.4
    • /
    • pp.749-759
    • /
    • 2014
  • With the rapid development of global economic and trade, the ports in the North-east Asia region have developed rapidly. Ocean shipping plays an irreplaceable role in China's foreign trade. Improvement of China's economy and continuous increase of trade in North-East Asia have made China as the number one in the world in container transport. Tianjin port which is the biggest international trade port in North-east China. Tianjin Binhai New District has incorporated in (CPC Central Committee on the outline of the Eleventh Five-Year Plan for national economic and social development proposals) which had adopted by The Fifth Plenary Session of the 16th CPC Central Committee. However, the competitions between ports are getting intense, the construction of Northeast Asia shipping center is in the ascendant, which bring new opportunity and challenge to the development of Tianjin port logistics. Therefore, Tianjin should according to its characteristics, integrating port resources, exert great efforts in developing port logistics, thus promoting regional economic development. Therefore, it is necessary to make the main study on the development strategy of Tianjin port logistics.

Accurate Range-free Localization Based on Quantum Particle Swarm Optimization in Heterogeneous Wireless Sensor Networks

  • Wu, Wenlan;Wen, Xianbin;Xu, Haixia;Yuan, Liming;Meng, Qingxia
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.12 no.3
    • /
    • pp.1083-1097
    • /
    • 2018
  • This paper presents a novel range-free localization algorithm based on quantum particle swarm optimization. The proposed algorithm is capable of estimating the distance between two non-neighboring sensors for multi-hop heterogeneous wireless sensor networks where all nodes' communication ranges are different. Firstly, we construct a new cumulative distribution function of expected hop progress for sensor nodes with different transmission capability. Then, the distance between any two nodes can be computed accurately and effectively by deriving the mathematical expectation of cumulative distribution function. Finally, quantum particle swarm optimization algorithm is used to improve the positioning accuracy. Simulation results show that the proposed algorithm is superior in the localization accuracy and efficiency when used in random and uniform placement of nodes for heterogeneous wireless sensor networks.

Corn Straw as Substrate for Producing Ethanol by Solid-State-Fermentation

  • Dong, Yong-Sheng;Qiao, Chang-Sheng;Wang, Rui-Ming;Wang, Li-Yan;Jia, Shi-Ru
    • Proceedings of the Korean Society for Applied Microbiology Conference
    • /
    • 2005.06a
    • /
    • pp.204-211
    • /
    • 2005
  • The technology of Solid-State-Fermentation (SSF) with corn straw by Pichia ohmeri T021 was studied in this article. After being crushed, the corn straw powder was added into vitriol solutions to hydrolysis, which the quality proportion of corn straw: water: vitriol (98%) is 20:80:1. The mixtures was incubated at 120$^{\circ}C$ for 1 hour, and the hydrolysis rate reached 19%. Following, the mixture was adjusted to pH 4.5 by sodium carbonate and added cellulase (25IFPU/g). The hydrolysis rate reached 15% after the mixture was incubated at 50$^{\circ}C$ for 25h. The mixture which hydrolysed by vitriol was inoculated by Pichia ohmeri T021 (5${\times}10^7$cell/g) and added cellulase (25 IFPU/g) at the same time. The ethanol yield reached 2.99g per 100 gram substrate after the fermenting grains was incubated at 33$^{\circ}C$, pH 4.5 for 5 days.

  • PDF

The Regulation of Sugar Metabolism in Huangguan Pears (Pyrus pyrifolia Nakai) with Edible Coatings of Calcium or Pullulan during Cold Storage

  • Kou, Xiaohong;Jiang, Bianling;Zhang, Ying;Wang, Jun;Xue, Zhaohui
    • Horticultural Science & Technology
    • /
    • v.34 no.6
    • /
    • pp.898-911
    • /
    • 2016
  • Sugars play many important roles in plant metabolism and directly influence fruit quality. The effects of two edible coatings, 2% calcium chloride and 1% pullulan, on sugar metabolism in postharvest Huangguan pear fruit were investigated during cold storage. The respiration rate, sugar content and composition, sucrose metabolism enzyme activities [acid invertase (AIV), neutral invertase (NI), sucrose synthase (SS), and sucrose phosphate synthase (SPS)] and expression of the AIV gene were analyzed during storage at $0^{\circ}C$ for 210 days. Coating treatments slowed the decrease of sucrose and hexose, the respiration rate, and the activities of AIV, NI, SS and SPS, thus maintaining high total soluble solids (TSS) and titratable acid (TA) contents in the fruit. There were no significant differences in AIV expression or activity between the treated and control groups of fruits. Both of the coatings could inhibit the activities of sucrose-cleaving enzymes, thus slowing the decrease of sugar content and maintaining high fruit quality during cold storage.

Active Distribution System Planning Considering Battery Swapping Station for Low-carbon Objective using Immune Binary Firefly Algorithm

  • Shi, Ji-Ying;Li, Ya-Jing;Xue, Fei;Ling, Le-Tao;Liu, Wen-An;Yuan, Da-Ling;Yang, Ting
    • Journal of Electrical Engineering and Technology
    • /
    • v.13 no.2
    • /
    • pp.580-590
    • /
    • 2018
  • Active distribution system (ADS) considering distributed generation (DG) and electric vehicle (EV) is an effective way to cut carbon emission and improve system benefits. ADS is an evolving, complex and uncertain system, thus comprehensive model and effective optimization algorithms are needed. Battery swapping station (BSS) for EV service is an essential type of flexible load (FL). This paper establishes ADS planning model considering BSS firstly for the minimization of total cost including feeder investment, operation and maintenance, net loss and carbon tax. Meanwhile, immune binary firefly algorithm (IBFA) is proposed to optimize ADS planning. Firefly algorithm (FA) is a novel intelligent algorithm with simple structure and good convergence. By involving biological immune system into FA, IBFA adjusts antibody population scale to increase diversity and global search capability. To validate proposed algorithm, IBFA is compared with particle swarm optimization (PSO) algorithm on IEEE 39-bus system. The results prove that IBFA performs better than PSO in global search and convergence in ADS planning.

The Nature of Acid-Catalyzed Acetalization Reaction of 1,2-Propylene Glycol and Acetaldehyde

  • Cheng, Chen;Chen, Hui;Li, Xia;Hu, Jianli;Liang, Baochen
    • Korean Chemical Engineering Research
    • /
    • v.53 no.4
    • /
    • pp.463-467
    • /
    • 2015
  • We investigated catalytic activity of ion-exchange resins in acetalization of 1,2-propylene glycol with acetaldehyde. The impacts of reaction variables, such as temperature, reaction time, catalyst loading and feedstock composition, on the conversion of 1,2-propylene glycol were measured. The life of the catalyst was also studied. Furthermore, the reaction kinetics of 1,2-propylene glycol acetalization was studied. It was found that reaction rate followed the first-order kinetics to acetaldehyde and 1,2-propylene glycol, respectively. Therefore, overall acetalization reaction should follow the second-order reaction kinetics, expressed as. Key words: 1,2-propylene Glycol, 2,4-dimethyl-1,3-dioxolane, Ion-exchange Resin, Polyhydroxy Compounds, Acetalization $r=kC^{nA}_AC^{nB}_B=19.74e^{\frac{-6650}{T}}C^1_AC^1_B$.

Experimental and theoretical studies on SHS column connection with external stiffening ring under static tension load

  • Rong, Bin;You, Guangchao;Zhang, Ruoyu;Ma, Xu;Quan, Xinxin
    • Steel and Composite Structures
    • /
    • v.28 no.2
    • /
    • pp.167-177
    • /
    • 2018
  • In order to investigate mechanical properties in the core area of Square Hollow Section(SHS) column connection with external stiffening ring, four specimens were tested under the static tension load. The failure modes, load-displacement curves and strain distribution were analyzed to study the mechanical properties and the load transfer mechanism of the core area of connections. The connections behave good ductility and load-bearing capacity under the static tension load. Parametric analysis was also conducted, in which the thickness of steel tube, extended width and thickness of the stiffening ring were considered as the parameters to investigate the effects on mechanical properties of the connections. Based on the experimental results, an analytical method for the bearing capacity of connection with external stiffening ring under the static tension load was proposed. The theoretical results and the experimental results are in good agreement, which indicates that the theoretical calculation method of the bearing capacity is advisable.