Wengfu Group Co.

China

Wengfu Group Co.

China
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Xiang S.,Wengfu Group Co. | Xiang S.,Guizhou University | Xiang S.,Xi'an Jiaotong University | Wang J.,Wengfu Group Co. | And 3 more authors.
Advanced Materials Research | Year: 2011

17-4PH precipitation-hardening martensite stainless steel is an important commercially available stainless steel. And the mechanical properties of this steel are very sensitive to quenching and aging process. In this paper, the effects of aging process on mechanical properties of this steel were investigated. The results show that the microstructure of this steel consists of quenched martensite, tempered martensite and precipitates. With the increase of the aging temperature, the strength decreases and the toughness increase. And the fracture mode of this steel transforms brittle fracture into toughness fracture.


Zhu J.,Guizhou University | Song X.X.,Guizhou University | Liu F.,Wengfu Group Co. | Li T.X.,Guizhou University
Advanced Materials Research | Year: 2013

As the widely used collector, environmental pollution and toxicity of xanthates have got more and more concerns. In the present work, the flocculation process had been used to treat xanthate wastewater. The results showed that Al2(SO4)3 was the optimal flocculant. At the conditions of dosage of 0.1mol L-1Al2(SO4)3 0.5 mL, the initial pH 6.5, vibrating time 90 min and settling time 120 min, sodium isobutyl xanthate was removed nearly up to 100%. © (2013) Trans Tech Publications, Switzerland.


Zhou M.,Wuhan University of Technology | Ying G.,Wuhan University of Technology | Li B.,Wuhan University of Technology | Xie T.,Wengfu Group Co.
Advanced Materials Research | Year: 2011

In this paper, an Infrared Sulfur Analyzer is set to measure the desulphurization degree during thermal decomposition of phosphor-gypsum, which provides a much quick, convenient, continuous and accurate method. It might be considered as an effective way to study kinetics of phosphor-gypsum (or phosphogypsum) thermal decomposition (or pyrolysis). With the help of this method, the desulphurization degree and desulphurization rate of broadly constituted phosphor-gypsum samples in the temperature range of 1250-1400°C were studied. The experimental results show that the desulphurization degree increase with the rising of temperature in the range of 1250-1300°C quickly, however, this increase is not obvious when the temperature is above 1300°C. Besides, the corresponding regression equations are obtained. The decomposition degree of phosphor-gypsum could be judged according to the regression equations mentioned above. © (2011) Trans Tech Publications, Switzerland.


Chen X.-H.,Guizhou University | Chen Y.,Guizhou University | Gan M.,Wengfu Group Co. | Xu K.-X.,Wengfu Group Co.
Guocheng Gongcheng Xuebao/The Chinese Journal of Process Engineering | Year: 2010

The separation of vanadium form sodium aluminate solution in Bayer process by precipitation method was investigated, focusing on the effect of various factors which influence recovery rate of vanadium pentoxide in precipitation process through the single factor experiment, such as precipitating agent dosage, precipitation reaction time, precipitation reaction temperature. The experimental results showed that it was more effective to choose evaporated mutterlauge as raw material, calcium oxide as precipitating agent for the experiments. Vanadic acid was the main existence form of the vanadium in evaporated mutterlauge. Precipitating agent dosage was the most primary factor affecting recovery rate of vanadium pentoxide, reaction temperature was the next one, reaction time was obviously most inferior. Under the condition of optimized single factor technological parameters (excess coefficient of calcium oxide 1000, reaction time 1 h, reaction temperature 90°C), the total recovery rate of vanadium pentoxide was up to 45.34%.


Ying G.,Wuhan University of Technology | Zhou M.,Wuhan University of Technology | Li B.,Wuhan University of Technology | Xie T.,Wengfu Group Co.
ICMREE2011 - Proceedings 2011 International Conference on Materials for Renewable Energy and Environment | Year: 2011

In order to develop automatic test so as to improve test efficiency and reduce test time, a new test method is designed to measure the desulphurization degree during thermal decomposition of phosphor-gypsum (or phosphogypsum). In this paper, an Infrared Sulfur Analyzer is set to measure the desulphurization degree of phosphor-gypsum more quickly, more conveniently, more continuously and more accurately. The desulphurization degree curve is obtained based on the test results. Besides, the corresponding regression equation are obtained, according to the test results, which shows that the desulphurization degree increase with the rising of temperature in the range of 1250-1300C quickly, however, this increasing is not obvious when above 1300C. The decomposition degree of phosphor-gypsum could be judged quickly and directly according to the regression equations above mentioned. © 2011 IEEE.


Deng G.,CHALCO Guizhou Branch | Li W.-F.,Wengfu Group Co.
Xi'an Jianzhu Keji Daxue Xuebao/Journal of Xi'an University of Architecture and Technology | Year: 2011

In the present paper, the use of the gradient design and the wide-band laser cladding technology, on the surface of the TC4 alloy, the powder of CaHPO4·2H2O+CaCO3 whose Ca/P is 1.4 and 1.5, was mixed to prepare the gradient bioceramic coating with hydroxyapatite Ca10(PO4)6(OH)2 (HA), β-tricalcium phosphate β-TCP[β-Ca3(PO4)2]. With the aid of scanning electron microscope (SEM), X-ray diffraction (XRD) and other analysis, different Ca/P effected on the bioceraic coating microstructure was studied. Result shows: because the phosphor (P) is burned under the condition of the laser, when Ca/P is 1.5, the ceramic structure after laser cladding has better crystalline state than the ratio 1.4 of Ca/P. Different Ca/P powder and CeO2 contents have significant impact on synthesizing HA+β-TCP. When Ca/P is 1.4 and the addition of CeO2 reaches 0.4wt%, the synthesizing HA + β-TCP is the greatest amount; and when Ca/P is 1.5 and the content of CeO2 is between 0.2wt% and 0.4wt%, the synthesizing HA + β-TCP is the greatest amount.


Wang F.,East China University of Science and Technology | Li J.,East China University of Science and Technology | Hu Q.,East China University of Science and Technology | Yang X.,East China University of Science and Technology | And 3 more authors.
European Journal of Organic Chemistry | Year: 2014

We describe our attempts to fine-tune the reactivity and selectivity of N-fluorobenzenesulfonamide in fluorination reactions by changing the substituents on its phenyl rings. A series of N-fluorobenzenesulfonamides bearing substituents at the ortho, meta, and para positions were prepared, and were used in the enantioselective fluorination of 2-oxindoles catalysed by chiral palladium complexes. Fluorinating reagents 1b, 1c, 1d, 1e, 1h, 1i, and 1j gave similar results to 1a, while 1f, 1g, and 1n gave worse yields and selectivities. Under mild reaction conditions, a series of 3-fluoro-2-oxindoles were obtained in excellent yields (up to 98%) and enantioselectivities (up to 99% ee) using N-fluoro-4,4′-difluoro-benzenesulfonamide as the fluorination agent. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


He H.-M.,Wengfu Group Co. | Gao L.,East China University of Science and Technology | Yang X.-J.,East China University of Science and Technology | Yang X.-J.,CAS Shanghai Institute of Organic Chemistry | And 8 more authors.
Journal of Fluorine Chemistry | Year: 2013

The polypropylene/polydimethylsiloxane/graphite fluoride (PP/PDMS/GF) composites are prepared with dynamic curing technology by simple blending of polypropylene, graphite fluoride and polydimethylsiloxane, and then their superhydrophobic properties are investigated. The results indicates that the static WCA reaches 148 with a sliding angle 6 for surface sandpapered PP/PDMS/GF = 100/20/15 composite, which supplies a much economical and convenient method for preparing superhydrophobic materials. © 2013 Elsevier B.V. All rights reserved.


Zhang Y.,East China University of Science and Technology | Yang X.-J.,East China University of Science and Technology | Yang X.-J.,CAS Shanghai Institute of Organic Chemistry | Yang X.-J.,Wengfu Group Co. | And 8 more authors.
Tetrahedron | Year: 2013

Structurally modified N-fluorobenzenesulfonimides (NFSIs) have been used to study the enantioselective fluorination of oxindoles in the presence of a bis-cinchona alkaloid, (DHQD)2PHAL, as the catalyst. We observe that the NFSI analogues bearing two tert-butyl groups at the para-position of the symmetric phenyl rings led to an enhanced enantioselectivity in most cases (up to 96% ee) compared with the unmodified NFSIs (less than 69% ee). © 2013 Elsevier Ltd. All rights reserved.


Hu H.,Xi'an University of Architecture and Technology | Hu H.,Wengfu Group Co. | Xu D.-L.,Xi'an University of Architecture and Technology | Xie T.,Wengfu Group Co. | Wang J.-P.,Wengfu Group Co.
Huaxue Gongcheng/Chemical Engineering (China) | Year: 2010

With lime milk as defluorinating agent, fluorine removal from acidic wastewater of phosphoric fertilizer plant was studied by using orthogonal test method. In the orthogonal test the influence of lime milk mass, reaction temperature, reaction time and four levels was analyzed on the yield and mass ratio of phosphorus to fluorine in wastewater. The results show that the key factors affecting the mass ratio of phosphorus to fluorine in wastewater are lime milk mass and the reaction temperature. The optimum technological conditions of acidic wastewater defluorination in phosphoric fertilizer plant are as follows: lime milk mass 1.25-1.30 times theoretical one, reaction temperature 55°C, and reaction time 1.5 h. Feed-grade calcium hydrogen phosphate can be prepared with defluorinated acidic wastewater in which the mass ratio of phosphorus to fluorine is more than 100.

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