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Liao R.,Hunan First Normal University | Sun C.,Zhongye Changtian International Engineering Co.
Journal of Computational and Theoretical Nanoscience | Year: 2016

Aiming at the lack in the traditional detecting algorithm for determining fall-down of the old through threshold value and disadvantage on easy leakage of privacy in the video detection, this paper proposes a kind of fall-down detecting algorithm based on the discriminant analysis of statistics. This algorithm extracts the characteristic value of behavior and establishes the characteristic vector space through the experimental analysis, and then the advantage of distance of sampling value from characteristic value is taken to judge whether this behavior is the value of fall-down state space. Meanwhile, the idea taking intelligent robot as the aided detection in the algorithm is put forward. Finally, this algorithm has good robustness, which verified by experiment. © 2016 American Scientific Publishers All rights reserved.

Wu X.,Tongji University | Li B.,Zhongye Changtian International Engineering Co. | Li J.,Zhongye Changtian International Engineering Co. | Ling Z.,Tongji University
Proceedings - 2016 International Conference on Smart City and Systems Engineering, ICSCSE 2016 | Year: 2016

The most important factor of influencing the durability of concrete bridge structure failure is reinforcement corrosion. The accelerated corrosion methods of laboratory with electricity is used to research mechanical properties of new material S23043 duplex stainless steel rusted. The maximum loss ratio of sectional area is used to express the degree of corrosion according to the corrosion status, and establish the corresponding simplified geometric model. The rule of corrosion rate changing with time is obtained and the regression equation of nominal yield strength, nominal ultimate strength and elongation with corrosion rate are resulted. Results of test reveal that S23043 duplex stainless steel bar corroded unevenly and many corrosion pits appeared on the surface. Corrosion rate appeared slow after the first fast with the conduction time. After reinforcement corrosion, The nominal yield strength, nominal ultimate strength, and elongation deteriorated in linearly with the increasing of corrosion rate, which could be considered as an reference for the durability evaluation of concrete structure and for the later engineering construction. © 2016 IEEE.

Qin W.,Central South University | Yang C.,Central South University | Lai S.,Zhongye Changtian International Engineering Co. | Wang J.,Central South University | And 2 more authors.
Bioresource Technology | Year: 2013

The leaching of chalcopyrite by moderately thermophilic microorganisms was investigated by employing cyclic voltammetry (CV), accompanying with the leaching behavior elucidation. Leaching experiment showed that there was clear benefit in leaching chalcopyrite within the low solution potential (below 400. mV vs. SCE), compared to the high potential leach (above 550. mV vs. SCE). Simultaneous maintenance of an appropriate concentration of total dissolved iron was necessary and also beneficial to leach chalcopyrite. The leaching results showed the existence of an optimum pH in the leaching of chalcopyrite by the moderately thermophilic microorganisms. The analysis of CV results revealed that the chalcopyrite was reduced to a series of intermediate products (such as talnakhite, bornite and chalcocite) in the cathodic, and then the intermediate product (chalcocite) was oxidized in the anodic. © 2012 Elsevier Ltd.

Gong S.,Xiangtan University | He F.,Xiangtan University | Liu K.,Zhongye Changtian International Engineering Co. | Long X.,Xiangtan University
Jixie Gongcheng Xuebao/Journal of Mechanical Engineering | Year: 2015

Aiming at the problem of using high-speed air jet to impact granular material layer, the parameter simulation model of high speed air jet is built by using realizable κ-ε turbulence model. The influence of nozzle diameter, jet distance on center axial velocity of jet is discussed on the basic of verifying the presented model feasibility, and the relations between jet distances, nozzle diameter and stagnation point pressure are obtained. The truck scale test platform of single-hole is established, and the experimental tests have been finished to obtain the relation curve between impacting mass and spray distance under different jet pressure. The process of using air jet to impact the iron granular layer is simulated by using the best spray distance length, which is obtained by experimental test. The mass distribution around the hole formed by jet impact is achieved by simulating method, and the variation of depth and diameter of hole with jet pressure is given. The results obtained by simulating are agreement with the test ones. It can provide guidance to use high-speed air jet to penetrate the granular material layer in the practical application. ©, 2015, Journal of Mechanical Engineering. All right reserved.

Zhang J.-Y.,Central South University | Zhang X.-H.,Central South University | Zhou J.-M.,Central South University | Dai C.-D.,Zhongye Changtian International Engineering Co. | Xie D.-J.,Central South University
Kang T'ieh/Iron and Steel (Peking) | Year: 2011

The sinter size, mass flow of inlet, material height, porosity and inlet temperature are the main parameters in affecting the waste heat recovery efficiency. Through researching a 360 m2 sinter cooler in an iron and steel company and heat transfer characteristics in sinter cooling process, the mathematical models of heat transfer were established. Based on the FLUENT 6.3, the two-equation energy model of non-equilibrium thermodynamics in porous media was built up by user-defined-scalar and user-defined-function. The five parameters were optimized to improve the waste heat recovery efficiency of the sinter cooler, and the optimal combination of these parameters was approved by orthogonal experimental method. Comparing the test data and the model prediction, it is shown that the model prediction and the real operation are in good agreement, this study provides a reliable theoretical basis in waste heat recovery efficiency in sinter.

Fang Z.-H.,Central South University | Wang L.-G.,Central South University | Xiong Z.-Y.,Zhongye Changtian International Engineering Co.
Caikuang yu Anquan Gongcheng Xuebao/Journal of Mining and Safety Engineering | Year: 2012

To analyze the mining disturbance influence scope in underground metal mine and its influence degree on ground structures more reasonably and quantitatively, combined with engineering practice in Hualinggou iron mine, we proposed that using Micromine to create true three-dimensional geological model in this paper, using hexahedral discrete technology to mesh the corresponding geological model, and using coupling technology and C language to reconstruct the numerical model in FLAC3D. On this basis, we analysed the influence scope of underground mining disturbance and its influence degree on ground tailings dam. The results show that, first, using coupling technology can create more complex three-dimensional geological model. Second, using numerical calculation method can de-lineate mining influence scope accurately. Finally, using this technology can analyze underground mining disturbance influence on ground structures in the quantitative view.

Sun W.,Central South University | Ouyang K.,Central South University | Ouyang K.,Zhongye Changtian International Engineering Co. | Zhang L.,Central South University | And 3 more authors.
Minerals Engineering | Year: 2010

Hydrolyzate of hogwash oil (HHO) was prepared at ambient pressure using hogwash oil that was collected from the dietary industry as a raw material by means of non-pressurized multistage hydrolyzation. Before hydrolyzation, the collected hogwash oil was subject to pre-treatment that included deposition edulcoration, acidification degumming and deodorization by digestion as well as vacuum dewatering. Components of the synthesized products were detected by gas chromatography and the results indicated that unsaturated fatty acids are the major components. Using HHO as a collector, the flotation behavior of diaspore and kaolinite was investigated. The reaction mechanisms of diaspore and kaolinite with HHO are discussed based on a zeta potential test. The results showed that a concentrate with a mass ratio of Al2O3 to SiO2 of 14.42 and an Al2O3 recovery of 81.80% can be obtained at a feed mass ratio of Al2O3 to SiO 2 of 5. This indicated that the HHO is a potential collector for separating diaspore from aluminosilicate minerals in bauxite. The results also suggested a possible way to reuse discarded hogwash oil to avoid environmental pollution. © 2009 Elsevier Ltd. All rights reserved.

Liu R.,Central South University | Sun W.,Central South University | Ouyang K.,Zhongye Changtian International Engineering Co. | Zhang L.,General Research Institute for Nonferrous Metals, China | Hu Y.,Central South University
Minerals Engineering | Year: 2015

In this study, ozonator combined with flotator (OCF) have been applied to treat the mineral processing wastewater. The process efficiency has been evaluated in the bench scale. Removing xanthate from aqueous solution was conducted by OCF. In all cases, the butyl xanthate concentration in the treated water was found to be negligible (<0.42 mg L- 1). The experiments were preceded under different reaction conditions to study the ozonation time and pH on the oxidation of butyl xanthate. The concentration of butyl xanthate and sulfide are analyzed at special time intervals to elucidate the decomposition of butyl xanthate. In addition, oxidation reduction potential and pH are continuously measured in the course of experiments. Chemical oxygen demand is chosen as a mineralization index of the ozonation of butyl xanthate. The degradation mechanism between butyl xanthate and ozone has been discussed. The OCF technology showed to be an efficient process, which requires ozone and flotator, and the treated water ended up with a very low residual concentration of xanthate and COD. It can be inferred from ultraviolet spectrum, HPLC-MS and COD measurement that SO4 2 - is produced. The COD of butyl xanthate solution declined dramatically, the removal rate of COD reached 72.21% when ozonation time is 60 min. And the biodegradability (BOD/COD) of butyl xanthate solution increased markedly and shifted from 0.251 to 0.361. It is believed that this ozonation-flotation technique, here named OCF, using ozonator and flotator has a high potential as a alternative method for pollutants removal (flotation reagents, such as butyl xanthate) form waste mining effluents. © 2014 Elsevier B.V. All rights reserved.

Li X.,Central South University | Yang H.,Central South University | Song X.,Central South University | Wu Y.,Zhongye Changtian International Engineering Co.
Journal of Non-Crystalline Solids | Year: 2013

Approximate glass forming region in the ZnO-Fe2O 3-P2O5 ternary system was determined. Structure and properties of two compositional series of xZnO-20Fe2O 3-(80 - x)P2O5 (A series, x = 20-40 mol.%) and xZnO-10Fe2O3-(90 - x)P2O5 (B series, x = 20-55 mol.%) were investigated. Phase identification was conducted by X-ray diffraction. Structural studies were carried out by Raman spectroscopy. Aqueous durability was measured by the glass dissolution rate in deionized water at 90 C. Thermal properties were measured by differential scanning calorimetry and thermal dilatometry. Samples with ≥ 60 mol.% P2O5 can form glasses, whereas samples with ≤ 30 mol.% P2O5 cannot form glasses. Glass forming ability increases with increasing ZnO/Fe 2O3 ratio for samples with fixed P2O 5 content which locates in the range of 35-60 mol.% P 2O5. Glass structure varies from metaphosphate to pyrophosphate with increasing ZnO content in each series. The structure variation leads to increase in density, aqueous durability and glass transition temperature and decrease in thermal expansion coefficient and thermal stability. Further improvement in thermal stability of these glasses with excellent aqueous durability in A and B series may improve their suitability for low-to-mid temperature sealing applications. © 2013 Elsevier B.V.

Zhang X.,Central South University | Zhang J.,Central South University | Dai C.,Zhongye Changtian International Engineering Co. | Xie D.,Central South University
Huagong Xuebao/CIESC Journal | Year: 2011

Through studying a 360 m 2 sinter cooler in an iron and steel company, a mathematical model for heat transfer in sinter cooling process is established. This model is based on the porous medium model, in which the momentum equation is corrected by Ergun equation and the energy equation is corrected by the two energy equations for local non-equilibrium thermodynamics. This model is solved with the user defined functions (UDF) and the user defined scalars (UDS) in the platform of computational fluid dynamics software, Fluent6.3.The sinter size, inlet velocity, material height, porosity and inlet temperature are the main parameters affecting the waste heat recovery efficiency. The five parameters are simulated and their optimal combination is determined by orthogonal experimental method for improving the waste heat utilization, which are as follows: sinter size 0.025 m, inlet velocity 7.65 m·s -1, material height 1.8 m, porosity 0.45, and inlet temperature 414 K. This model is verified reliable by comparison with the test data. The method can be used for design of sinter coolers. © All Rights Reserved.

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