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Granule Size Distribution and Porosity of Granule Packing

Journal of Iron and Steel Research International 2008年第5期15卷 1-5页

作者： DAI Shu-hua SHEN Feng-man YU Ai-bing School of Materials and Metallurgy Northeastern University Shenyang 110004 Liaoning China School of Raw Material Science and Engineering University of New Southern Wales Sydney NSW2052 Australia

The granule size distribution and the porosity of the granule packing process were researched. For realizing the optimizing control of the whole sintering production process, researchers must know the factors influencing the granule size distribution and the porosity. Therefore, tests were carried out in the laboratory with regard to the influences of the size and size distribution of raw materials and the total moisture content on the size and size distribution of granule. Moreover, tests for finding out the influences of the moisture content and the granule volume fraction on the porosity were also carried out. The results show that （1） the raw material has little influence on granulation when its size is in the range of 0. 51 mm to 1.0 mm; （2） the influence of the material size on granule size plays a dominant role, and in contrast, the moisture content creates a minor effect on granule size; （3） in binary packing system, with the increase in the constituent volume fraction, the porosity initially increases and then decreases, and there is a minimum value on the porosity curve of the binary mixture system; （4） the minimum value of the porosity in binary packing system occurs at different locations for different moisture contents, and this value shifts from right to left on the porosity curve with increasing the moisture content; （5） the addition of small granules to the same size component cannot create a significant influence on the porosity, whereas the addition of large granules to the same system can greatly change the porosity.

关键词： granule raw material size distribution granulation granule packing porosity

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The effectiveness of zinc supplementation in men with isolated hypogonadotropic hypogonadism

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Asian Journal of Andrology 2017年第3期19卷 280-285页

作者： Yan-Ling Liu man-Na Zhang Guo-Yu Tong Shou-YueSun Yan-hua zhu Ying Cao Jie Zhang Hong huang Ben Niu Hong Li Qing-hua Guo Yan Gao Da-Long zhu Xiao-Ying Li Shanghai Institute of Endocrinology and Metabolism Department of Endocrinology and Metabolism Ruijin Hospital Shanghai Jiao Tong University School of Medicine Shanghai 200025 China Department of Endocrinology Drum Tower Hospital Affiliated to Nanjing University Medical School Nanjing 210008 China Department of Endocrinology The Third Affiliated Hospital Sun Yat-sen University Guangzhou 510630 China Department of Endocrinology and Metabolism Nanfang Hospital Southern Medical University Guangzhou 510515 China Department of Endocrinology Guangxi Medical University and First Affiliated Hospital Nanning 530021 China Department of Endocrinology The First People's Hospital of Yunnan Province Kunming 650032 China Department of Endocrinology The Affiliated Hospital of Guiyang Medical College Guiyang 550004 China 00853 China.

A multicenter, open-label, randomized, controlled superiority trial with 18 months of follow-up was conducted to investigate whether oral zinc supplementation could further promote spermatogenesis in males with isolated hypogonadotropic hypogonadism （IHH） receiving sequential purified urinary follicular-stimulating hormone/human chorionic gonadotropin （uFSH/hCG） replacement. Sixty-seven Chinese male IHH patients were recruited from the Departments of Endocrinology in eight tertiary hospitals and randomly allocated into the sequential uFSH/hCG group （Group A, n = 34） or the sequential uFSH plus zinc supplementation group （Group B, n = 33）. In Group A, patients received sequential uFSH （75 U, three times a week every other 3 months） and hCG （2000 U, twice a week） treatments. In Group B, patients received oral zinc supplementation （40 mg day-1） in addition to the sequential uFSH/hCG treatment given to patients in Group A. The primary outcome was the proportion of patients with a sperm concentration 〉1.0 × 106 ml-1 during the 18 months. The comparison of efficacy between Groups A and B was analyzed. Nineteen of 34 （55.9%） patients receiving sequential uFSH/hCG and 20 of 33 （60.6%） patients receiving sequential uFSH/hCG plus zinc supplementation achieved sperm concentrations ≥1.0 × 106 ml-1 by intention to treat analyses. No differences between Group A and Group B were observed as far as the efficacy of inducing spermatogenesis （P = 0.69）. We concluded that the sequential uFSH/hCG plus zinc supplementation regimen had a similar efficacy to the sequential uFSH/hCG treatment alone. The additional improvement of 40 mg day-1 oral zinc supplementation on spermatogenesis and masculinization in male IHH patients is very subtle.

关键词： gonadotropin isolated hypogonadotropic hypogonadism masculinization spermatogenesis zinc supplementation

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Reduction behavior and mechanism of Hongge vanadium titanomagnetite pellets by gas mixture of H2 and CO

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Journal of Iron and Steel Research International 2017年第1期24卷 34-42页

作者： Wei Li Gui-qin Fu man-sheng Chu Miao-yong zhu School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina

Hongge vanadium titanomagnetite（HVTM）pellets were reduced by H2-CO gas mixture for simulating the reduction processes of Midrex and HYL-III shaft *** influences of reduction temperature,ratio ofφ（H2）toφ（CO）,and pellet size on the reduction of HVTM pellets were evaluated in detail and the reduction reaction kinetics was *** results show that both the reduction degree and reduction rate can be improved with increasing the reduction temperature and the H2 content as well as decreasing the pellet *** rational reduction parameters are reduction temperature of 1050℃,ratio ofφ（H2）toφ（CO）of 2.5,and pellet diameter in the range of 8-11 *** these conditions（pellet diameter of 11mm）,final reduction degree of 95.51% is *** X-ray diffraction（XRD）pattern shows that the main phases of final reduced pellets under these conditions（pellet diameter of 11 mm）are reduced iron and *** peak intensity of reduced iron increases obviously with the increase in the reduction ***,relatively high reduction temperature promotes the migration and coarsening of metallic iron particles and improves the distribution of vanadium and chromium in the reduced iron,which is conducive to subsequent melting *** the early stage,the reduction process is controlled by interfacial chemical reaction and the apparent activation energy is 60.78kJ/*** reduction process is controlled by both interfacial chemical reaction and internal diffusion at the final stage,and the apparent activation energy is 30.54kJ/mol.

关键词： Hongge vanadium titanomagnetite Pellet Gas-based direct reduction Behavior and mechanism Kinetics

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Running-in Test and Fractal Methodology for Worn Surface Topography Characterization

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Chinese Journal of Mechanical Engineering 2010年第5期23卷 600-605页

作者： JI Cuicui zhu hua JIANG Wei LU Binbin School of Mechanical and Electrical Engineering China University of Mining and Technology Xuzhou 221116 China School of Mechanical Engineering University of Leeds Leeds LS2 9JZ UK

Studying and understanding of the surface topography variation are the basis for analyzing tribological problems,and characterization of worn surface is *** geometry offers a more accurate description for surface roughness that topographic surfaces are statistically self-similar and can be quantitatively evaluated by fractal *** change regularity of worn surface topography is one of the most important aspects of running-in ***,the existing research normally adopts only one friction matching pair to explore the surface topography change,which interrupts the running-in wear process and makes the experimental result lack authenticity and *** this paper,to investigate the change regularity of surface topography during the real running-in process,a series of running-in tests by changing friction pairs under the same operating conditions are conducted on UMT-II Universal Multifunction *** surface profile data are acquired by MiaoXAM2.5X-50X Ultrahigh Precision Surface 3D Profiler and analyzed using fractal dimension D,scale coefficient C and characteristic roughness Ra ＊based on root mean square（RMS） *** characterization effects of the three parameters are discussed and *** results obtained show that there exists remarkable fractal feature of surface topography during running-in process,both D and Ra ＊increase gradually,while C decreases slowly as the wear-in process goes on,and all parameters tend to be stable when the wear process steps into the normal wear *** ＊illustrates higher sensitivity for rough surface characterization compared with the other two *** addition,the running-in test carried with a set of identical surface properties is more scientific and reasonable than the traditional *** proposed research further indicates that the fractal method can quantitatively measure the rough surface,which also provides an evidence for running-in process identification and tribology d

关键词： running-in worn surface topography RMS method fractal dimension scale coefficient characteristic roughness

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Methane and nitrous oxide fluxes from four tundra ecotopes in Ny-lesund of the High Arctic

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Journal of Environmental Sciences 2014年第7期26卷 1403-1410页

作者： Qingqing Chen Renbin zhu Qing Wang hua Xu Institute of Polar Environment School of Earth and Space Sciences University of Science and Technology of China State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences

During the summers of 2008 and 2009, net methane（CH4） and nitrous oxide（N2O） fluxes were investigated from 4 tundra ecotopes： normal lowland tundra（LT）, bird sanctuary tundra（BT）, the tundra in an abandoned coal mine（CT） and the tundra in scientific bases（ST） in Ny-Alesund of the High Arctic. Tundra soils in CT（184.5 ± 40.0 μg CH4/（m2·hr）） and ST（367.6 ± 92.3 μg CH4/（m2·hr）） showed high CH4 emissions due to the effects of human activities, whereas high CH4 uptake or low emission occurred in the soils of LT and *** lowland tundra soils（mean,-4.4-4.3 μg N2O/（m2·hr）） were weak N2 O sources and even sinks. Bird activity increased N2 O emissions from BT with the mean flux of7.9 μg N2O/（m2·hr）. The mean N2 O fluxes from CT（45.4 ± 10.2 μg N2O/（m2·hr）） and ST（78.8 ± 18.5 μg N2O/（m2·hr）） were one order of magnitude higher than those from LT and BT, indicating that human activities significantly increased N2 O emissions from tundra soils. Soil total carbon and water regime were important factors affecting CH4 fluxes from tundra soils. The N2 O fluxes showed a significant positive correlation with ammonia nitrogen（NH4＋-N） contents（r = 0.66, p 〈 0.001） at all the observation sites, indicating that ammonia nitrogen（NH4＋-N） content acted as a strong predictor for N2 O emissions from tundra soils. The CH4 and N2O fluxes did not correspond to the temperature variations of soil at 0-15 cm *** our results implied that human activities might have greater effects on soil CH4 and N2O emissions than current climate warming in Ny-Alesund, High Arctic.

关键词： Tundra soilMethaneNitrous oxideArcticGreenhouse gases

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Theoretical Research and Experimental Validation of Elastic Dynamic Load Spectra on Bogie Frame of High-speed Train

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Chinese Journal of Mechanical Engineering 2016年第3期29卷 498-506页

作者： zhu Ning SUN Shouguang LI Qiang ZOU hua Engineering Research Center of Structure Reliability and Operation Measurement Technology of Rail Guided Vehicles Ministry of Education Beijing Jiaotong University

When a train runs at high speeds, the external exciting frequencies approach the natural frequencies of bogie critical components, thereby inducing strong elastic vibrations. The present international reliability test evaluation standard and design criteria of bogie frames are all based on the quasi-static deformation hypothesis. Structural fatigue damage generated by structural elastic vibrations has not yet been included. In this paper, theoretical research and experimental validation are done on elastic dynamic load spectra on bogie frame of high-speed train. The construction of the load series that correspond to elastic dynamic deformation modes is studied. The simplified form of the load series is obtained. A theory of simplified dynamic load–time histories is then deduced. Measured data from the Beijing–Shanghai Dedicated Passenger Line are introduced to derive the simplified dynamic load–time histories. The simplified dynamic discrete load spectra of bogie frame are established. Based on the damage consistency criterion and a genetic algorithm, damage consistency calibration of the simplified dynamic load spectra is finally performed. The computed result proves that the simplified load series is reasonable. The calibrated damage that corresponds to the elastic dynamic discrete load spectra can cover the actual damage at the operating conditions. The calibrated damage satisfies the safety requirement of damage consistency criterion for bogie frame. This research is helpful for investigating the standardized load spectra of bogie frame of high-speed train.

关键词： elastic dynamic load spectra finite element method modal deformation calibration bogie frame high-speed train

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Distribution of platinum group elements in road dust in the Beijing metropolitan area, China

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Journal of Environmental Sciences 2007年第1期19卷 29-34页

作者： WANG Juan zhu Ruo-hua SHI Yan-zhi Department of Chemistry Capital Normal University Beijing 100037 China

Dust samples collected from the Beijing metropolitan area （China） were evaluated to determine the distribution and the concentration of platinum group elements （PGEs）. The dust particles that were smaller than 100 mesh size fraction （150 μm） were analyzed after aqua regia digestion. Concentrations ofPt, Rh, and Pd were found to be between 3.96 and 356.3 ng/g, 2.76 and 97.11 ng/g, and 0.1 and 124.9 ng/g, respectively, in the urban areas of Beijing, whereas for the background samples collected from the suburbs of Beijing, the concentrations of Pt, Pd, and Rh were very low and ranged from 0.1 to 0.9 ng/g, 0.5 to 1.4 ng/g, and 0.8 to 2.2 rig/g, respectively. The distributions of PGEs in road dust were an accurate reflection of the levels of pollution and were found to match with the local traffic conditions. A strong positive correlation was established among all the dements found in road dust. This suggests that emissions of abraded fragments from vehicle exhausts may be the source of the high concentration of Pt, Rh, and Pd in road dust along the main roads of Beijing.

关键词： platinum (Pt) palladium (Pd) rhodium (Rh) road dust distribution environmental pollution

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Preparation of Ni2P/Al-SBA-15 catalyst and its performance for benzofuran hydrodeoxygenation

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Chinese Journal of Chemical Engineering 2017年第12期25卷 1784-1790页

作者： Tianhan zhu hua Song Xueya Dai hualin Song Provincial Key Laboratory of Oil & Gas Chemical Technology College of Chemistry & Chemical Engineering Northeast Petroleum University Daqing 163318 China Key Laboratory of Cancer Prevention and Treatment of Heilongjiang Province Mudanjiang Medical University Mudanjiang 157011 China

The Al-doped Ni2P/AI-SBA-15 catalyst with high hydrodeoxygenation （HDO） activity was synthesized by tem- perature programmed reduction at a relatively low reduction temperature of 400 ℃. The as-prepared catalyst was characterized by X-ray diffraction （XRD）, H2 temperature-programmed reduction （H2-TPR）, X-ray photoelectron spectroscopy （XPS）, transmission electron microscope （TEM）, NH3 temperature programmed desorption （NH3-TPD）, N2 adsorption-desorption and CO uptake. The effect of AI on benzofuran （BF） HDO performance was investigated. The result indicates that the incorporation of AI into the SBA-15 support can promote the formation of much uniform, smaller, highly dispersed N2P particles on the catalyst. The AI also contrib- utes to suppress the enrichment of P and promote more exposed Ni sites on the surface. In addition, the incorporation of AI can enhance the acid strength. The total deoxygenated product yield over Ni2P/AI-SBA-15 reached 90.3%, which is an increase of 19.4%, when compared with that found for Ni2P/SBA-15 （70.9%）.

关键词： Ni2P SBA-15 Hydrodeoxygenation Benzofuran AI

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Insights into metals in individual fine particles from municipal solid waste using synchrotron radiation-based micro-analytical techniques

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Journal of Environmental Sciences 2015年第1期27卷 298-308页

作者： Yumin zhu hua Zhang Liming Shao Pinjing He State Key Laboratory of Pollution Control and Resources Reuse Tongji University Institute of Waste Treatment and Reclamation Tongji University Research and Training Center on Rural Waste management Ministry of Housing and Urban–Rural Development of P.R. China

Excessive inter-contamination with heavy metals hampers the application of biological treatment products derived from mixed or mechanically-sorted municipal solid waste（MSW）. In this study, we investigated fine particles of 〈 2 mm, which are small fractions in MSW but constitute a significant component of the total heavy metal content, using bulk detection techniques. A total of 17 individual fine particles were evaluated using synchrotron radiation-based micro-X-ray fluorescence and micro-X-ray diffraction. We also discussed the association, speciation and source apportionment of heavy metals. Metals were found to exist in a diffuse distribution with heterogeneous intensities and intense hot-spots of 〈 10 μm within the fine particles. Zn–Cu, Pb–Fe and Fe–Mn–Cr had significant correlations in terms of spatial distribution. The overlapped enrichment, spatial association, and the mineral phases of metals revealed the potential sources of fine particles from size-reduced waste fractions（such as scraps of organic wastes or ceramics） or from the importation of other particles. The diverse sources of heavy metal pollutants within the fine particles suggested that separate collection and treatment of the biodegradable waste fraction（such as food waste） is a preferable means of facilitating the beneficial utilization of the stabilized products.

关键词： Municipal solid waste Fine particle Synchrotron radiation Micro-analytical technique Metal

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Determinations of the Configuration of C-20 in Derivatives of Adynerin Using DFT/HF Methods

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Chemical Research in Chinese Universities 2007年第5期23卷 592-597页

作者： hua Yan REN Jie CHEN Chang-xiang zhu hua-jie Organic Synthesis and Natural Product Laboratory State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany Chinese Academy of Science Kunming 650204 P. R. China Southwest Foresty University Kunming 650224 P. R. China

The configurations of C-20 in derivatives of novel 5α-adynerin type,co-existing glycoside in pair,were identified with the calculated chemical shifts of carbon at the B3LYP/6-311＋G（2d,p）*** glycosides are unusual ... 详细信息

关键词： Configuration determination Adynerin derivative B3LYP GIAO NMR computation

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