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Feasibility analysis of gob-side entry retaining on a working face in a steep coal seam

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International Journal of Mining Science and Technology 2014年第4期24卷 499-503页

作者： Deng Yuehua Wang Shouquan Sichuan Coal Industry Group limited Liability company

Based on the decline in exploitation of coal resources, steep coal seam mining and mining face tensions continue to explore the feasibility analysis of steeply inclined faces in the gob. One of the key factors in utilizing the technology of gob-side entry retaining in steep coal seams is to safely and effectively prevent caving rock blocks from rushing into the gob-side entry by sliding downwards along levels. Using theoretical analysis and field methods, we numerically simulated the mining process on a fully-mechanized face in a steep coal seam. The stress and deformation process of roof strata has been analyzed, and the difficulty of utilizing the technology is considered and combined with practice in a steep working face in Lvshuidong mine. The feasibility of utilizing the technology of gob-side entry retaining in a steep coal seam has been recognised. We propose that roadways along the left lane offshoot body use a speciallymade reinforced steel dense net to build a dense rock face at the lower head. The results show that the lane offshoot branch creates effective roof control, safe conditions for roadway construction workers, and practical application of steeply inclined gob.

关键词： Gob-side entry retaining Steep coal seam Fully-mechanized mining Feasibility analysis Numerical simulation

Effects of Spiral Magnetic Field on Structures Transformation and Macrosegregation of Sn-Pb Alloy

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Acta Metallurgica Sinica(English Letters) 2013年第3期26卷 345-351页

作者： Xingguo ZHANG Qian ZHAO Jianshe GUO Qingyuan XING Liang DENG Xiaoguang HOU Canfeng FANG School of Materials Science and Engineering Dalian University of Technology Baoshan Iron and Steel company limited

The effect of spiral magnetic field （SMF） on the solidification process of Sn-20 wt.%Pb hypoeutectic alloy was studied in this work. The temperature distribution and the macrosegregation together with the eutectic lamellar spacing during solidification were measured under different magnetic fields. The results indicate that the compositions in the top and bottom portions of the sample are nearly the same and the segregation phenomenon is basically eliminated by SMF at an exciting current of 125 A. The morphology of the primary phase transforms from coarse dendrite to rosette or ellipsoidal equiaxed crystal and the spacing of the eutectic lamellar increases from 1.6 to 3.9 μm when the exciting current increases from 0 to 125 A. Moreover, if the exciting current is high enough, the forced fluid flow caused by SMF will enhance the process of transition from lamellar eutectic structure to anomalous rod-like one.

关键词： Spiral magnetic field Forced convection Eutectic lamellar spacing Sn-Pb alloy Composition segregation

Synthesis of Nano-ZSM-5 in Ultra-Concentrated System and Its Performance in Diesel Hydrodewaxing

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China Petroleum Processing & Petrochemical Technology 2016年第4期18卷 25-31页

作者： Qin Lihong Li Haiyan Li Jun Sun Famin china university of petroleum Beijing102249 daqing chemical research center petrochemical research institutepetrochina company limitedDaqing163714 daqing petrochemical company construction company petrochina company limitedDaqing163714

Nanocrystalline ZSM-5(with a crystal size in the range of 20—30 nm) has been synthesized in only 20 h via the crystallization of ultra-concentrated homogeneous synthesis mixtures. The influence of low water content, use of compound surfactant, a proper crystallization time and SiO_2/Al_2O_3 molar ratio on the properties of the final nanocrystalline ZSM-5 has been studied. Especially, the use of compound surfactant has influenced some properties of nano-ZSM such as the morphology, crystal size and crystallization greatly. The nano-ZSM-5 zeolite was investigated using XRD, BET, SEM, NH_3-TPD, and other techniques. The evaluation results in a 200-mL hydrogenation unit indicated that the synthesized nano-ZSM-5 had excellent catalytic performance in diesel hydrodewaxing.

关键词： ultra-concentrated system nano-ZSM-5 diesel hydrodewaxing

Optimization of tensile strength for new type acetone-urea-formaldehyde furan resin using uniform design

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China Foundry 2011年第1期8卷 30-35页

作者： Lin Shengjun Zhao Wei Li Yuancai Tong Siyi Wang Wenqing School of Materials Science and Engineering Huazhong University of Science and Technology Wuhan 430074 Hubei China Guangxi Yuchai Machinery company limited Yulin 537005 Guangxi China

In this study,the 24 h tensile strength of new type acetone-urea-formaldehyde furan resin (nitrogen content 3%) was investigated by uniform design *** independent variables such as acetone:formaldehyde molar ratio (mol/mol),solution pH value,reaction temperature (℃) and reaction time (min) were considered in the experiments.U13(134) uniform design was employed and the equation of 24 h tensile strength model was obtained after 13 *** 24 h tensile strength was optimized by applying single factor experiments and stepwise non-linear regression *** (Minitab 15 trial version) and MATLAB (R2010a trial version) were used for data *** t-value and p-value indicate that the major impact factors include the interaction effect of solution pH value and reaction temperature (X2X3),the linear terms of acetone:formaldehyde molar ratio (X1),reaction time (X4) followed by the square effects of acetone/formaldehyde molar ratio (X1X1).The optimized results were achieved with the acetone:formaldehyde molar ratio (mol/mol) at 3:1,solution pH value at 6.0,reaction temperature at 70℃,and reaction time at 140 min,*** method can not only significantly reduce the number and cost of the tests,but also provide a good experimental design strategy for the development of furan *** investigation shows that the predicted results of 24 h tensile strength are consistent well with the experimental ones.

关键词： acetone-urea-formaldehyde furan resin 24 h tensile strength single factor experiment uniform design stepwise regression

Role of Rare Earth in Low Sulphur Nb-Ti-Bearing Steel

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Journal of Rare Earths 2003年第1期21卷 81-85页

作者：朱兴元林勤曾静刘继雄高平祥王跃华 wuhan University of Technology Physical Chemistry Department Center of wuhan Iron and Steel company Railway Engineering Equipment and Materials Works of wuhan Iron and Steel company

The effect of rare earth on the microstructures, mechanical properties and inclu sions in low sulphur Nb-Ti-bearing steel were investigated. It is shown that t h e transverse yield point, the traverse tensile strength and elongation of testin g steels decrease initially and then rise with increasing content of rare earth. The impact energy values of the testing steels exhibit a contrary trend. Proper amount of rare earth in the steels can improve the anisotropy of impact toughne ss above -20 ℃ and it does not affect the type of microstructures which ar e st ill composed of ferrites and pearlites, but the pearlite amount increases. On one hand, rare earth cleans the molten steel and reduces the amount of inclusions; on the other hand, rare earth makes the inclusions spheroidizd, refi ned and dispersed, and thus improves the distribution of inclusions.

关键词： metal materials Nb-Ti-bearing steel prop erty microstructure inclusion rare earths

Preparation and Characterization of an Intelligent Multitarget Tracking HA-RGD-CLB-QDs Drug Delivery System

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Journal of wuhan University of Technology(Materials Science) 2017年第6期32卷 1493-1502页

作者：吴峰政徐海星 ZHU Zhihua LI Xin Lü Yahui MA Tian CAI Xinjie LI Rui WANG Xiaobing 许沛虎 School of Chemistry Chemical Engineering and Life Sciences Wuhan University of Technology Wuhan 430070 China wuhan Science and Technology Bureau Wuhan 430070 China wuhan Kanghua Century Pharmaceutical company Wuhan 430070 China

This work aimed to develop an intelligent multi-target tracking hyaluronic acid-RGDchlorambucil-quantum dots（HA-RGD-CLB-QDs） drug delivery system. After deacetylated, hyaluronic acid was reacted with anticancer drug chlorambucil, RGD, and quantum dots to obtain the HA-RGD-CLB-QDs drug delivery system. The characterization by FT-IR, ~1 H NMR, TEM, XPS, DLS, and UV-vis absorption and fluorescence spectra show that the system is successfully constructed with an average particle size of about 70 nm. The results of the drug release profile show that that the system has a p H and enzyme sensitive controlled release behaviour. Moreover, cellular uptake and toxicity results show that the system has an ideal dual receptormediated endocytosis pathway that significantly enhances the efficacy of CLB tumor therapy and has a lower toxicity to normal *** system shows the potential application as a carrier for cancer therapy.

关键词： drug delivery system hyaluronic acid quantum dots RGD dual-receptor

Geochronological Records of Oil-Gas Accumulations in the Permian Reservoirs of the Northeastern Ordos Basin

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Acta Geologica Sinica(English Edition) 2013年第6期87卷 1701-1711页

作者： CHEN Gang YANG Fu LI Shuheng ZHANG Huiruo HU Yanxu LEI Panpan State Key Laboratory of Continental Dynamics Department of Geology Northwest University Changqing Oilfield company PetroChina Company Limited CNPC

Geochronology of oil-gas accumulation （OGA） is a challenging subject of petroleum geology in multi-cycle superimposed *** K-Ar dating of authigenic illite （AI） and fluid inclusion （FI） analysis combined with apatite fission track （AFT） thermal modeling,a case study of constraining the OGA times of the Permian reservoirs in northeast Ordos basin （NOB） has been conducted in this *** dating of the Permian oil-gas-bearing sandstone core-samples shows a wide time domain of 178-108 *** distribution of the AI ages presents 2-stage primary OGA processes in the Permian reservoirs,which developed in the time domains of 175-155 Ma and 145-115 Ma with 2-peak ages of 165 Ma and 130 Ma,*** FI temperature peaks of the samples and their projected ages on the AFT thermal path not only present two groups with a low and a high peak temperatures in ranges of 90-78℃ and 125-118℃,respectively corresponding to 2-stage primary OGA processes of 162-153 Ma and 140-128 Ma in the Permian reservoirs,but also appear a medium temperature group with the peak of 98℃ in agreement with a secondary OGA process of c.～30 Ma in the Upper Permian *** integrated analysis of the AI and FI ages and the tectono-thermal evolution reveals that the Permian reservoirs in the NOB experienced at least 2-stage primary OGA processes of 165-153 Ma and 140-128 Ma in agreement with the subsidence thermal process of the Mid-Early Jurassic and the tectono-thermal event of the Early ***,the Upper Permian reservoirs further experienced at least 1-stage secondary OGA process of c.～30 Ma in coincidence with a critical tectonic conversion between the slow and the rapid uplift processes from the Late Cretaceous to Neogene.

关键词： northeast Ordos basin (NOB) Permian sandstone reservoirs oil-gas accumulation (OGA) geochronology

Oxidation behavior of artificial magnetite pellets

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International Journal of Minerals,Metallurgy and Materials 2017年第6期24卷 603-610页

作者： Han-quan Zhang Jin-tao Fu School of Resource and Civil Engineering Wuhan Institute of Technology Wuhan 430205 China Western Mining company Xi’ning 810001 China

The oxidation behavior of artificial magnetite pellets was investigated through measurements of the oxidation degree and mineralogical analysis. The results show that artificial magnetite pellets are much easier to oxidize than natural magnetite. The oxidation is controlled through two different reaction mechanisms. The oxidation of artificial magnetite is dominated by internal diffusion, with an activation energy of 8.40 kJ/mol, at temperatures less than 800°C, whereas it is controlled by chemical reaction, with a reaction activation energy of 67.79 kJ/mol, at temperatures greater than 800°C. In addition, factors such as the oxygen volume fraction and the pellet diameter strongly influence the oxidation of artificial magnetite: a larger oxygen volume fraction and a smaller pellet diameter result in a much faster oxidation process.

关键词： artificial magnetite pellets oxidation reaction mechanisms

Behavior of Rare Earthsin UltraLowSulfur Microalloyed Steel

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Journal of Rare Earths 1999年第3期17卷 207-212页

作者：刘勇华林勤叶文陈宁郭英陈祝清祝庆和 Department of Physical Chemistry University of Science and Technology Beijing Beijing 100083 China wuhan Iron and Steel company Wuhan 430083 China

The investigation on the behavior of RE in microalloyed steel containing Nb and Ti indicates RE still have the effect of purifying molten steel and metamorphose inclusions even when the composition of S is pretty low(S<0 003%). The optimum performance of the experimental steels can be obtained when w RE / w O+S is controlled around 3 9. The content of solid solution RE can reach 1×10 -5 ～1×10 -4 order of magnitude in ultra low sulfur steel. The additions of RE can reduce the segregation of S and P at the grain boundary, delay the dynamic recrystallization, refine the grain and second phase particles, and promote the precipitation of (Nb, Ti)(C, N). RE also exhibit the microalloying effect in steel.

关键词： Rare earths Extra low sulfur steel Microalloying