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Low Temperature Reduction Degradation Characteristics of Sinter,Pellet and Lump Ore

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Journal of Iron and Steel Research International 2011年第8期18卷 20-24页

作者： WU Sheng-li liu xiao-qin zhou Qi XU Jian liu Cheng-song School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China

The reduction degradation characteristics of typical sinter, pellet and lump ore were tested with the reducing gas conditions simulating two kinds of irowmaking processes. The results show that, in the same condition of gas composition and temperature, the reduction degradation degree （RDI〈3.15mm） of sinter is high, RDI〈3.15mm of lump ore is low and RDI〈3.15 mm of pellet is in the middle level. With two kinds of gas composition simulating different iron-making processes, the reduction degradation indices （RDI） of three kinds of iron ores all present the tenden- cy of ＂inverted V-shape＂ in the temperature range from 450 to 650℃, and the RDI reach the maximum value at 550℃. The reduction degradation degrees of iron ores are extended when mixing the gas with hydrogen to increase the re duction potential, and the influence extent is discrepant for different iron ores. Colligating the increase amplitude of grains in small size fraction, the influence of reducing gas on lump ore is the greatest, the influence on sinter is the second, and the sensitivity of pellet on the reducing gas properties change is relatively small. As for the degradation form, lump ore and sinter both present the degradation ,of cracking, and the distribution of small grains generated from the cracking is in the range from 03 5 to 6. 3 mm uniformly. The lump ore presents surface cracking, while sin- ter presents integral cracking. The pellet presents the degradation of surface stripping, and the proportion of grains smaller than 0.5 mm is the highest, which is up to 90% in the grains smaller than 3.15 mm.

关键词： sinter pellet lump ore low temperature reduction degradation characteristic gas property

Membrane-based acoustic metamaterial with near-zero refractive index

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Chinese Physics B 2017年第1期26卷 237-242页

作者： Yi-Feng Li Jun Lan Hui-Yang Yu xiao-zhou liu Jia-Shu Zhang Department of Computer Science and Technology Nanjing Technology University Nanjing 211800 China Key Laboratory of Modern Acoustics Ministry of Education Nanjing University Nanjing 210093 China Key Laboratory of Modem Acoustics Ministry of Education Institute of Acoustics and School of Physics Nanjing University Nanjing 210093 China Department of Electronic and Electrical Engineering The University of Sheffield Sheffield S102TN UK

We investigate a one-dimensional acoustic metamaterial with a refractive index of near zero（RINZ） using an array of very thin elastic membranes located along a narrow waveguide pipe. The characteristics of the effective density, refractive index, and phase velocity of the metamaterial indicate that, at the resonant frequency fm, the metamaterial has zero mass density and a phase transmission that is nearly uniform. We present a mechanism for dramatic acoustic energy squeezing and anomalous acoustic transmission by connecting the metamaterial to a normal waveguide with a larger cross-section. It is shown that at a specific frequency f1, transmission enhancement and energy squeezing are achieved despite the strong geometrical mismatch between the metamaterial and the normal waveguide. Moreover, to confirm the energy transfer properties, the acoustic pressure distribution, acoustic wave reflection coefficient, and energy transmission coefficient are also calculated. These results prove that the RINZ metamaterial provides a new design method for acoustic energy squeezing,super coupling, wave front transformation, and acoustic wave filtering.

关键词： acoustic metamaterial refractive index of near zero(RINZ) energy squeezing transmission enhancement

Involvement of α5 integrin in survivin-mediated osteosarcoma metastasis

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Asian Pacific Journal of Tropical Medicine 2016年第5期9卷 465-469页

作者： xiao-zhou liu Cheng-Jun Li Su-Jia Wu Xin Shi Jian-Ning Zhao Southern Medical University Department of Orthopedics Jinling Hospital Medical School of Nanjing University

Objective: To investigate the role of survivin in osteosarcoma metastasis. Methods: Small interfering RNA(si RNA) was used to knockdown the expression of survivin and α5 integrin in the human osteosarcoma cell line MG63. Western blotting and immunostaining methods was used to assessed the effect of survivin knockdown on the expression of α5 integrin through flow cytometry and fluorescence microscopy detection. Meanwhile, the invasion and migration of transfected cells in Transwell and wound healing assays were probed, and the growth situation of these cells transplanted into nude mice was monitored. Results: Knockdown of survivin expression could inhibit the invasion and migration of osteosarcoma MG64 cells in vitro and the expression of α5 integrin on osteosarcoma MG64 cell surface, suggesting that survivin can inhibit the invasion and migration of osteosarcoma cells through downregulation of α5 integrin. Anti-α5 integrin antibody could also markedly decrease the capability of invasion and migration of osteosarcoma MG64 cells. Additionally, knockdown of survivin expression could slow the growth of osteosarcoma MG63 cells transplanted into nude mice. Conclusions: Survivin-directed anti-tumor strategies might be an effective method in the treatment of osteosarcoma.

关键词： Survivin α5 integrin Osteosarcoma Metastasis

Micro-crack detection of nonlinear Lamb wave propagation in three-dimensional plates with mixed-frequency excitation

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Chinese Physics B 2020年第1期29卷 336-345页

作者： Wei-Guang Zhu Yi-Feng Li Li-Qiang Guan Xi-Li Wan Hui-Yang Yu xiao-zhou liu College of Computer Science and Technology Nanjing Tech UniversityNanjing 211800China Key Laboratory of Modern Acoustics Ministry of EducationNanjing UniversityNanjing 210093China Key Laboratory of Modern Acoustics Ministry of EducationInstitute of Acoustics and School of PhysicsNanjing UniversityNanjing 210093China

We propose a nonlinear ultrasonic technique by using the mixed-frequency signals excited Lamb waves to conduct micro-crack detection in thin plate *** models of three-dimensional(3D)aluminum plates and composite laminates are established by ABAQUS software,where the aluminum plate contains buried crack and composite laminates comprises cohesive element whose thickness is zero to simulate delamination *** interactions between the S0 mode Lamb wave and the buried micro-cracks of various dimensions are simulated by using the finite element *** frequency spectrum analysis is applied to the received time domain signal and fundamental frequency amplitudes,and sum and difference frequencies are extracted and *** results indicate that nonlinear Lamb waves have different sensitivities to various crack *** is a positive correlation among crack length,height,and sum and difference frequency amplitudes for an aluminum plate,with both amplitudes decreasing as crack thickness increased,i.e.,nonlinear effect weakens as the micro-crack becomes *** amplitudes of sum and difference frequency are positively correlated with the length and width of the zero-thickness cohesive element in the composite ***,amplitude ratio change is investigated and it can be used as an effective tool to detect inner defects in thin 3D plates.

关键词： nonlinear Lamb wave mixed-frequency micro-cracks amplitude ratio

The 9th International Symposium on Modern Acoustics （continued）

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南京大学学报（自然科学版） 2013年第1期49卷 1-4页

作者： Zhang Shu-Yi Qiu xiao-Jun liu xiao-zhou Key Laboratory of Modern Acoustics and Institute of Acoustics Nanjing University Nanjing 210093 China

The 9th International Symposium on Modern Acoustics was held in Nanjing,China,on May 19 -22,2012,which has been introduced in an article published in Journal of Nanjing University (Natural Sciences),2012[1].As described previously,after peer reviewing,a part of the original papers were selected to be published in Journal of Nanjing University(Natural Sciences),which were separated as two issues:the first has already been published in a special issue of the journal in 2012[2～19].

关键词：《南京大学学报》期刊编辑工作发行工作

多孔CeO_2膜的制备及其光谱性能（英文）

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光谱学与光谱分析 2018年第4期38卷 1324-1328页

作者：刘小珍石兴菊刘小舟任晓辉陈捷周洁华上海应用技术大学化学与环境工程学院上海201418 贛南师范大学江西贛州341000 Regenia AB Stockholm 10691Sweden

以铈箔为原料,采用阳极氧化法和热处理法制备多孔的CeO_2膜。将阳极氧化铈膜分别在400,500和800℃下进行热处理,分别研究阳极氧化铈膜的晶体结构、组成和表面形貌,分别研究多孔的CeO_2膜红外光谱特征吸收和热膨胀性能。阳极氧化铈膜是Ce... 详细信息

以铈箔为原料,采用阳极氧化法和热处理法制备多孔的CeO_2膜。将阳极氧化铈膜分别在400,500和800℃下进行热处理,分别研究阳极氧化铈膜的晶体结构、组成和表面形貌,分别研究多孔的CeO_2膜红外光谱特征吸收和热膨胀性能。阳极氧化铈膜是Ce(OH)_3,CeF_3,Ce_2O_3,CeO_2和Ce的混合膜,并吸附水和乙二醇,其中Ce(OH)_3,CeF_3,Ce_2O_3分别为六方晶型结构,CeO_2和Ce分别为立方晶型结构。阳极氧化铈膜中的Ce(OH)_3,Ce_2O_3和Ce分别在400和500℃进行热处理时可能分别转变为CeO_2,分别在400和500℃热处理后的膜为CeF_3和CeO_2的混合膜。阳极氧化铈膜中的Ce(OH)_3,CeF_3,Ce_2O_3和Ce在800℃进行热处理时可能分别转变为CeO_2,在800℃热处理后的膜为CeO_2膜。该CeO_2膜是多孔的膜,且孔为直孔,在1 600~4 000cm^(-1)范围内具有强吸收。该CeO_2膜在170~900℃范围内热膨胀系数变化不大,该膜的热稳定性较好。

关键词：阳极氧化法 CeO2膜 X衍射谱能谱

Ultrasonic characterization of porcine liver tissue at frequency between 25 to 55 MHz

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World Journal of Gastroenterology 2006年第14期12卷 2276-2279页

作者： xiao-zhou liu Xiu-Fen Gong Dong Zhang Shi-Gong Ye Bing Rui State Key Laboratory of Modern Acoustics Institute of Acoustics Nanjing University Nanjing 210093 Jiangsu Province China Nanjing Meat Processing Plant Nanjing 210015 Jiangsu Province China

AIM： To study the relation between acoustic parameters and histological structure of biological tissue and to provide the basis for high-resolution image of biological tissues and quantitative ultrasonic diagnosis of liver disease. METHODS： Ultrasonic imaging and tissue characterization of four normal porcine liver and five cirrhotic liver tissue samples were performed using a high frequency imaging system. RESULTS： The acoustic parameters of cirrhotic liver tissue were larger than those of normal liver tissue. The sound velocity was 1577 m/s in normal liver tissue and 1631 m/s in cirrhotic liver tissue. At 35 MHz, the attenuation coefficient was 3.0 dB/mm in normal liver tissue and 4.1 dB/mm in cirrhotic liver tissue. The backscatter coefficient was 0.00431 dB/Srmm in cirrhotic liver tissue and 0.00303 dB/Srmm in normal liver tissue. The backscatter coefficient increased with the frequency. The high frequency images coincided with their histological features. CONCLUSION： The acoustic parameters, especially the sound backscatter coefficient, are sensitive to the changes of liver tissues and can be used to differentiate between the normal and pathological liver tissues. High frequency image system is a useful device for highresolution image and tissue characterization.

关键词： Porcine liver tissue Hepatocirrhosis High frequency imaging Tissue characterization Acoustic parameter

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我国重要有色金属资源——铜矿的现状及展望

西北地质 2007年第1期40卷 83-88页

作者：刘小舟中国冶金地质工程勘查总局西北地质勘查院汉中分院陕西汉中723000

铜及其合金材料被广泛地应用于电子工业、机器制造、军事工业、农业等经济领域,是现代工业、农业、国防和科学技术必需的金属材料。铜在自然界中,主要呈硫化物及其类似化合物和铜的氧化物、自然铜以及铜的硫酸盐、碳酸盐、硅酸盐等类型... 详细信息

铜及其合金材料被广泛地应用于电子工业、机器制造、军事工业、农业等经济领域,是现代工业、农业、国防和科学技术必需的金属材料。铜在自然界中,主要呈硫化物及其类似化合物和铜的氧化物、自然铜以及铜的硫酸盐、碳酸盐、硅酸盐等类型矿物存在,已发现约有280多种,其中主要矿物16种。铜矿石的自然类型一般按物相分析中含氧化矿和硫化矿的比例不同,分为硫化矿石(含氧化铜在10%以下)、混合矿石(含氧化铜10%～30%)和氧化矿石(含氧化铜在30%以上)3种。我国铜矿主要分布在江西、云南、湖北、西藏、甘肃、安徽、山西、黑龙江等省,具有以下特点:(1)矿床规模小。(2)共生伴生矿多,品位低。(3)适合采用浸出-萃取-电积工艺的斑岩型铜矿少,降低生产成本的空间受到限制。(4)剩余储量中规模大、品位高的矿床多处于边远地区,外部建设条件差,在目前的金融、财税政策下,难以开发利用。总体上,我国铜矿资源在数量和品位等方面均比较差,其国际竞争力低,铜资源特别是富铜资源不足,已是不争的事实。近十余年来我国铜矿保有储量总体上处于一个相对平稳的状态,即新增探明储量和矿山消耗储量大体平衡。我国快速增长的铜消费主要靠进口解决。

关键词：铜矿用途现状展望

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低压引射式煤粉喷射器的设计

流体机械 2012年第9期40卷 39-42页

作者：刘效洲广东工业大学广东广州510006

使用低压气体喷射器作为工业锅炉的煤粉气力输送装置,介绍了低压煤粉气力输送喷射器的工作原理,并利用公式推导和计算,得出了给定条件下的低压喷射器的设计参数以及主要结构尺寸,可以用来指导工程设计。最后采用fluent软件对其进行了计... 详细信息

使用低压气体喷射器作为工业锅炉的煤粉气力输送装置,介绍了低压煤粉气力输送喷射器的工作原理,并利用公式推导和计算,得出了给定条件下的低压喷射器的设计参数以及主要结构尺寸,可以用来指导工程设计。最后采用fluent软件对其进行了计算,揭示了煤粉在喷射器内的运动规律,取得了良好的效果。

关键词：低压喷射器负压煤粉气力输送设计方法