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Science China(life Sciences) 2012年第12期55卷 1057-1063页

作者： li ChunYan WANG WeiZhuo GUO Xlong ZHANG Feng MA WeiJuan ZHANG YinGang li youfen BAI YiDong LAMMI Mikko J Faculty of Public Health Medical College of Xi'an Jiaotong University Key Laboratory of Environment and Gene Related Diseases of Min- istry of Education Key Laboratory of Trace elements and Endemic Diseases of Ministry of Health Xi'an 710061 China 1nstitute of Health Education of Xi'an Xi'an 710004 China Department of Orthopedics Surgery Second Hospital Xi'an Jiaotong University Xi'an 710004 China Department of Orthopedics Surgery First Hospital Xi'an Jiaotong University Xi'an 710061 China School of life Science and Technology Xi'an Jiaotong University Xi'an 710049 China Department of Cellular and Structural Biology University of Texas Health Sciences Center at San Antonio San Antonio Texas 78229 USA Department of Anatomy Institute of Biomedicine University of Kuopio Kuopio F1N-70211 Finland

In this paper, we present the first evidence of differences in the mitochondria-related gene expression profiles of adult articular cartilage derived from patients with Kashin-Beck disease and normal controls. The expression of 705 mitochondria-related genes was analyzed by mitochondria-related gene expression analysis and ingenuity pathways analysis. Mitochondria-related gene expression analysis identified 9 up-regulated genes in Kashin-Beck disease based on their average expression ratio. Three canonical pathways involved in oxidative phosphorylation, apoptosis signaling and pyruvate metabolism were identified, which indicate the involvement of mitochondrial dysfunction in the pathogenesis of Kashin-Beck disease.

关键词： Kashin-Beck disease microarray mitochondrial dysfunction IPA analysis

Studies on Dual-beam Spectrometric Simultaneous Determination of Platinum and Rhodium with Water-Insoluble Porphine T(3-M-4HP)P

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Chemical Research in Chinese Universities 1991年第2期7卷 91-95页

作者： li youfen and Zheng Yanzhi (Department of Chemistry, Xiangtan University, Xiangtan)

The optimal conditions for the complexation reaction of meso- tetra(3-methoxy-4-hy-droxyphenyl) porphine T(3-M-4HP)P with platinum and rhodium are presented. Beer' s Law is obeyed when the concentration of rhodium is in the range of 0. 45-1.15 μg/25mL. The molar absorptivity of rhodium was found to be 1.99×106 L·mol-1·cm-1 at 460 nm. The value of εPt was found to be 6. 28×105 L·mol-1·cm-1 by linear regression method. The K coefficient method and compensating coefficient were used to determine platinum and rhodium simultaneouly without removal or masking of the interferents in the sample. The results for the determination of platinum and rhodium in the mixed solution of platinum and rhodium are satisfactory.

关键词： Platinum Rhodium Spectrophotonletry Meso-tetra(3-M-4HP)P.

Sintering Behavior and Microstructure of diphasic β-Sialon /Al_2O_3 Composites

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International Journal of Minerals,Metallurgy and Materials 1997年第4期11卷 34-38页

作者： li youfen HONG Yanruo ZHONG Xiangchong li Tingshou(National laboratory on Solid Electrolytes and Metallurgical Testing Techniques, USTB, Beijing 100083, China)

Six compositions with different ratio of β-Sialon/Al2O3 were synthesized from Al2O3, Si3,N4 and SiO2 by sintering with 3%Y2O3(mass fraction) as addition under the cover with powders of SiC+C and at nitrogen atmosphere. Theeffects of atmosphere, sintering temperature and composition on the sintering behavior were studied. The results showedthat the composites reached the best sintering behavior with the highest density about 92% at 1 650℃ under the weakreduction atmosphere. Finally the relative density of diphasic β-Sialon and p-Sialon/Al2O3 composites were studied andpredicted using ANN (Artificial Neural Networks) method and the results were experimental examined by fore randomsamples.

关键词： β-Sialon sintering behavior microstructure ANN

Spectrophotometric Study of Reaction Between Platinum and α,β,γ,δ-Tetra-(2-Chlorophenyl) Porphyrin

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Chemical Journal of Chinese Universities 1988年第2期 12-16页

作者： li youfen and Xiao Hong(Department of Chemistry, Xiangtan University, Xiantan)

The present paper describes the complex reaction of α, β,γ, δ-tetra-(2-chlorophenyl} porphyrin with platinum in the presence of the mixture surfactant, sodium dodecylbenzene sulfonate and OP, and a new highly sensitive method for spectrophotometric determination of micro amounts of platinum. Beer’s Law was obeyed when the concentration of platinum was in the range of 0?.2μg/25ml. The molar absorptivity was found to be 3.1×106 L mol-1 cm-1 at 417nm.

关键词： α β γ δ-Tetra-(2-chlorophenyl) porphyrin Platinum Spectrophotometry

BIOCHEMICAL STUDIES ON GLUCOAMINOGLYCANS CONTENT IN AFFECTED CARTILAGE HYALURONIC ACID LEVELS IN SERUM AND SYNOVIAL FLUID OF IDIOPATHIC FEMORAL HEAD NECROSIS

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Journal of Pharmaceutical Analysis 1999年第2期13卷 162-166,175页

作者： li Xudong,Wang Kunzheng,Chen Junchang, li youfen,Dang Xiaoqian,Pang Wei,Zhu liDepartment of Orthopaedic Surgery, Second Clinical Medical College of Xi′an Medical University, Xi′an 710004 Department of Orthopaedic Surgery Second Clinical Medical College Xi'an Medical University Xi'an 710004 China

To investigate the role of cartilage alterations in the pathogenesis of the idiopathic femoral head necrosis, 3 components of glycosaminoglycans(GAG) in pathological and health cartilage, levels of hyaluronic acid(HA) in synovial fluid and serum were detected. The correlations among HA level in synovial fluid, serum and GAG content in cartilage were analyzed. The results showed that ①the three components of cartilage GAG in normal adults and children showed little difference; ②Compared with the normal autopsy specimens, steroid induced ANFH and Perthes disease specimens had significantly decreased GAG contents (P0 05), but it decreased significantly (P0 05); ③Children suffered from Perthes disease had a much higher level of HA in serum than the controls (Plinical theory basis for auxiliary treatment to cartilage in early stage; ②Sulfate radical depletion is the most conspicuous one of GAG changes in middle and late stage. It sugges

关键词： glycosaminoglycans hyaluronic acid osteonecrosis femoral head Perthes disease

Neighborhood Carpooling Project in Changqing Community in Wuhan City

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China City Planning Review 2010年第4期19卷 46-53页

作者： WANG Chao, liU Qihua, RAO Jinling, SONG youfen li Caige

In the light of the increasingly severe traffic congestion in the city, the rising number of private cars on the road and the low occupancy rate of those cars, this paper explores the current legal obstacles to carpooling and proposes "neighborhood carpooling" as an innovative mobility project aimed at alleviating traffic pressure in the areas around residential districts and reducing the use of private cars. The paper begins by introducing the preparatory investigation, consultation and scheme design process, and then elaborates on the series of measures undertaken to ensure that the project runs smoothly, including the formulation and distribution of the proposal, establishment of carpooling stations, registration and management of carpooling information, signing of the voluntary undertakings, design of the carpooling stickers and encouragement of public participation through the media. The analysis of different data on the actual practice of carpooling and the results of the media survey shows that the "neighborhood carpooling" project can indeed reduce private car use and has achieved certain social benefits through media publicity. Finally, the paper points out that with the guarantee of the two-level management system involving the community administrative committee and the residents’ committees, effective community organization is the key to the successful operation of the project.

关键词： neighborhood carpooling traffic congestion communi

ZrO2-C-ZrB2复合材料的氧化动力学

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复合材料学报 2009年第1期26卷 103-107页

作者：李友芬王德伟北京化工大学北京市新型高分子材料制备与加工重点实验室北京100029

通过差热-热重分析研究了ZrB2含量为10%的ZrO2-C-ZrB2复合材料在800～1100℃下空气中的氧化动力学,根据气固相反应原理建立氧化动力学模型,计算反应表观活化能,并得到氧化速率与温度的经验关系式。结果表明,试样在800℃时的氧化过程仅... 详细信息

通过差热-热重分析研究了ZrB2含量为10%的ZrO2-C-ZrB2复合材料在800～1100℃下空气中的氧化动力学,根据气固相反应原理建立氧化动力学模型,计算反应表观活化能,并得到氧化速率与温度的经验关系式。结果表明,试样在800℃时的氧化过程仅有化学反应控速阶段与化学反应和气体扩散共同作用的混合控速阶段。900～1100℃的氧化过程为前期是化学反应控速阶段,中期为混合控速阶段,后期为扩散控速阶段。三个阶段的表观活化能分别为111.7、71.5和166.0 kJ·mol^-1。材料等温氧化的质量变化规律表明在900℃～1100℃内的氧化属于保护型氧化。

关键词： ZrO2-C-ZrB2复合材料氧化动力学模型反应速度表观活化能

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溶胶-凝胶法制备硅酸锆粉体及其表征

北京化工大学学报（自然科学版） 2015年第2期42卷 65-69页

作者：胡刚李友芬北京化工大学材料科学与工程学院材料电化学过程与技术北京重点实验室北京100029

通过溶胶-凝胶法制备ZrSiO4粉体,研究了煅烧温度、保温时间和催化剂(铁离子)对ZrSiO4合成率的影响;采用XRD、SEM、激光粒度仪等分析了ZrSiO4的晶相组成、结晶形貌以及产物粒径大小。实验结果表明:未添加催化剂时,ZrSiO4的合成温度高达1... 详细信息

通过溶胶-凝胶法制备ZrSiO4粉体,研究了煅烧温度、保温时间和催化剂(铁离子)对ZrSiO4合成率的影响;采用XRD、SEM、激光粒度仪等分析了ZrSiO4的晶相组成、结晶形貌以及产物粒径大小。实验结果表明:未添加催化剂时,ZrSiO4的合成温度高达1500℃;引入催化剂铁离子之后,在1200℃合成率可达到91.20%,合成温度降低了300℃,得到的粉体颗粒发育完善,结晶性好。烧结机理分析表明,Si4+的扩散是影响硅酸锆形成的主要因素;加入的铁以Fe3+的形式进入到ZrSiO4结构中,取代部分Si4+,产生空位,加速Si4+的扩散,从而有效地促进ZrSiO4的结晶,降低ZrSiO4的合成温度。

关键词：硅酸锆溶胶-凝胶法合成率铁离子

Al_2O_3/蒙脱土:Eu^(2+)架状结构发光材料的制备及发光性能研究

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中国稀土学报 2014年第3期32卷 275-281页

作者：王琦李友芬齐士成北京化工大学材料电化学过程与技术北京重点实验室北京100029

采用高温固相法,在还原气氛下制备出Al2O3/蒙脱土:Eu2+光致发光材料。研究了原料配比、烧结温度、保温时间以及激活剂Eu2+的含量对发光性能的影响。实验结果表明:加入蒙脱土后,所制备的样品仍保持Al2O3的架状结构,晶格常数发生变化,晶... 详细信息

采用高温固相法,在还原气氛下制备出Al2O3/蒙脱土:Eu2+光致发光材料。研究了原料配比、烧结温度、保温时间以及激活剂Eu2+的含量对发光性能的影响。实验结果表明:加入蒙脱土后,所制备的样品仍保持Al2O3的架状结构,晶格常数发生变化,晶体产生畸变,使得Eu2+更容易进入到晶格中。荧光光谱分析显示,发射光谱是两个宽峰组成,对应于Eu2+的4f65d→4f7(8S7/2)宽带允许跃迁。发光机制分析认为,宽峰结构由Eu0.92[Al1.76Si2.24O8]新相产生,生成的新相增加了Eu2+的取代格位,形成新的发光中心。因此Eu2+不仅取代了Al2O3八面体中Al的格位,而且取代了蒙脱土层间所吸附的阳离子格位,使样品发光强度提高了220%。

关键词： Al2O3 蒙脱土固相合成架状结构发射光谱稀土