69 research outputs found

    Catalytic Behaviors and Stability of Y_2O_3-Modified Ni/SiO_2 for Partial Oxidation of Methane into Synthesis Gas

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    采用常规浸渍法制备Y_2O_3修饰的Ni/SiO_2催化剂,并考察其催化甲烷部分氧化(POM)制合成气反应性能。结果表明,Y_2O_3的引入减小了金属Ni的粒径,有效提高了Ni在载体表面的分散性,增强了金属Ni与载体SiO_2间的相互作用,从而使催化剂的抗烧结、抗积碳能力,以及催化剂的POM反应性能得以改善。A series of Y_2O_3-modified Ni SiO_2 catalysts were synthesized by a conventional impregnation method.Catalytic performances for the partial oxidation of methane(POM) to synthesis gas were investigated.The addition of Y_2O_3 promotes a decrease in size of Ni particles supported on silica,increased the dispersion of Ni particles,and enhanced the interaction between Ni and silica.These properties gave the catalysts increased anti-sintering and resistance to carbon deposits.The catalytic behaviors of the Ni-based catalysts for POM were significantly improved when Y_2O_3 was introduced.国家自然科学基金(21373169);; 教育部创新团队项目(IRT1036)资助~

    Study of the water pollution control management program——A case study of the northeast of Jiaozhou Bay

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    以水质目标和管理费用为约束条件,建立了水污染控制管理方案优化模型,并将其成功应用于胶州湾东北部的水污染控制管理,提出了有利于胶州湾东北部经济和水环境可持续发展的优化管理方案。实例研究表明,该优化模型可应用于水污染控制管理中,可为海岸带地区制定水污染控制方案提供科学依据。The water management optimization model is developed by introducing the water quality model and overhead expenses as constraint condition.The model has been used to plan the water management of the northeast of Jiaozhou Bay.And the optional management plan,benefit to the sustainable developments of the local economics and the water environment,has been worked out,which the water quality has been attain the quality standard and cost is the minimum.The calculation example shows that the optimizing model is very effective and can be applied generally to water pollution control planning,which can provide scientific basis for the water control management scheme in coastal zone.国家海洋第三海洋研究所基本科研业务费专项资金资助项目(海三科2011017);国家海洋局海洋公益性行业科研专项经费项目(200805065

    Numerical modeling and biomechanical analysis of the human mitral valve

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    目的建立人体心脏二尖瓣仿真模型,模拟二尖瓣闭合的工作过程,分析二尖瓣各组件应力分布,探讨二尖瓣瓣叶和腱索的相互作用,并探寻腱索受力大小与腱索粗细之间的相关性。方法构建二尖瓣几何模型,在此基础上定义模型单元类型、材料属性、接触、载荷及约束,建立有限元模型,计算模型的应力、速度和位移等参数。结果瓣膜上的应力分布不均匀,后瓣叶亚区之间的裂口位置所受应力最大;不考虑腱索连接至瓣叶时,瓣叶负载后外翻至心房一侧;考虑腱索连接至瓣叶时,前、后瓣叶关闭良好;各腱索受力不同,与前瓣叶相连的支持腱索受力最大,腱索受力大小与腱索粗细之间的线性相关系数为0.954。结论瓣叶中心和后瓣叶亚区之间的裂口两处应力较大区域是临床上二尖瓣裂的常发生部位;与瓣叶相连的腱索可在瓣叶负载时,施加牵拉力使瓣叶不致发生翻转,前、后瓣叶恰好关闭;解剖结构粗壮的腱索受力较大。Objective To establish a numerical model of human mitral valve and simulate its closing process,so as to analyze stress distributions on the valve apparatuses,study the interaction between leaflets of mitral valve and chordae tendineae,and explore the relationship between the force of chordae tendineae and their thickness.Methods A geometric model of human mitral valve was constructed.On the basis of the geometric model,the finite element model was established by defining the element type,material attributes,contacts,loads and constraints.Parameters such as stress,velocity and displacement were calculated after solving the model.Results The stress distribution on the valve was non-uniform.The clefts between the scallops in the posterior leaflet were always under the highest load.When no chordae tendineae were attached,the leaflets turned over to the side of the atrium.When chordea tendineae were attached,the anterior and posterior leaflet could close up successfully.Different chordae tendineae applied different forces to the valve.The strut chorea tendineae attached to the anterior leaflet applied highest force among all the chordea tendineae.The correlation coefficient between the thickness of chordae tendineae and their force was 0.954.Conclusions The two zones with higher stresses,namely the center of the leaflet and the clefts between the three scallops in the posterior leaflet,are also the positions of mitral valve cleft in clinic.Chordea tendineae can apply the pulling force on the leaflets while the mitral valve is under load,thus the leaflets won't turn over to the side of atrium and the valve can close up in time.Chordea tendineae with thicker anatomic structure always apply a higher force on the leaflets.国家自然科学基金资助项目(61102137); 福建省自然科学基金资助项目(2011J01366); 福建省创新医学科研基金(2009-CXB-59

    A CAD/CAM method of individualized prosthesis base on CT reconstructing and robot grinding

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    人体髋关节髓腔具有个性化的S型形状,现有标准型的直柄股骨假体与病人髓腔形成三点接触,降低了股骨假体与病人髓腔的匹配度。利用猪腿骨的CT数据重建其; 髓腔的三维模型,将该三维模型作为假体设计模型导入机器人仿真软件进行编程和磨削仿真,并生成机器人磨削程序,利用机器人磨削程序将该假体模型复制到铜棒; 上。将加工好的假体与猪腿骨髓腔匹配,通过X射线图检测两者匹配情况,利用截取的骨断面测量假体与髓腔断面间的尺寸误差,验证个性化假体设计方法以及机器; 人磨削个性化假体的可行性。实验结果表明,假体与髓腔完成匹配后,90.84%匹配区域的假体与髓腔的间隙小于1mm。Human hip joint has a S-shaped canal , the existing standard straight; hip prosthesis matching with the femur cavity of the patient , will form; a three-point contact and reduce the fit precision between hip; prosthesis and femur cavity. The pig shank CT data is applied to; reconstruct the three-dimensional model of femur cavity to as a design; model of the prothesis, which is imported into robot simulation software; for programming and simulation of grinding , then,the prosthesis model; is copied on the copper bar by using robotic grinding technology. After; the prosthesis matched with femur cavity, the matching case is detected; by X-ray image , and the size error between the prosthesis and femur; cavity on the cross-sectional is measured to verify the method of; individualized prosthesis design and the feasibility of robot grinding; prosthesis. The experimental results show that 90.84% of the matching; area is less than 1mm when the femur cavity is matched with prosthesis

    PREPARATION OF QUATERNARY CINCHONINE TARTRATE SALTS BY MICRO COLUMN CHROMATOGRAPHY

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    报道了用微型柱色谱制备用于不对称相转移催化和多相不对称催化合成的辛可宁季铵盐Preparation of quaternary cinchonine tartrate salts by micro column chromatography is described.国家自然科学基金资助项目 ( 2 99330 4 0

    Design and fabrication of uncemented femoral prosthesis using CAD/CAM/Robotic integration method

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    背景:生物型股骨柄假体无菌松动是全髋关节置换失败的主要因素,减少无菌松动的先决条件是增加股骨柄假体在股骨髓腔中的填充率。目的:得到定制式股骨柄假体在髓腔中的填充率,验证计算机辅助设计/计算机辅助制造/工业机器人加工(CAd/CAM/rObOTIC)集成方法和机器人磨削的有效性。方法:利用CT数据重建股骨髓腔三维模型,在此三维模型基础上设计股骨柄假体的柄体,依据标准直柄股骨柄假体近端模型设计股骨柄假体的其余部分。将设计的股骨柄假体模型导入CAd/CAM/rObOTIC集成系统生成机器人磨削轨迹,利用该轨迹对股骨柄假体进行磨削加工。将加工好的股骨柄假体与股骨髓腔匹配,分析股骨柄假体在髓腔中的填充率。结果与结论:实验结果表明,定制式股骨柄假体在髓腔中有良好的填充率,髓腔的解剖结构可以阻止股骨柄假体的扭转,获得股骨柄假体在髓腔中的稳定固定。BACKGROUND: In total hip replacements, aseptic loosening of uncemented femoral hip prosthesis is the main reason for the failure of artificial hip replacement, the prerequisite of reducing aseptic loosening of prosthesis is to increase filling area of femoral prosthesis in femoral cavity.OBJECTIVE: To obtain the filling rate of customized femoral prosthesis in femoral cavity and verify the validity of the methods of CAD/CAM/Robotic integration and the robot grind.METHODS: In this paper, the CT data of femur were used to reconstruct three-dimensional model of femoral cavity.According to this model, a custom uncemented femoral hip prosthesis was designed, then the model of this custom prosthesis was imported into the CAD/CAM/Robotic software to generate cut path.After the cut path was imported into the robotic controller, the custom prosthesis can be fabricated, then this custom prosthesis was inserted into the femoral cavity, and the filling result of the custom prosthesis in femoral cavity was analyzed.RESULTS AND CONCLUSION: The experiment results showed that the customized prosthesis in femoral cavity achieved good filling result, the structure of femoral cavity resisted the rotation of the customized prosthesis in femoral cavity, and the customized prosthesis obtained stable fixation in the femoral cavity

    双能谷效应对N型掺杂Si基Ge材料载流子晶格散射的影响

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    性能优越的Si基高效发光材料与器件的制备一直是Si基光电集成电路中最具挑战性的课题之一.Si基Ge材料不仅与成熟的硅工艺相兼容,而且具有准直接带特性,被认为是实现Si基激光器最有希望的材料.对Si基Ge材料N型掺杂的研究有利于提示出其直接带发光增强机理.本文研究了N型掺杂Si基Ge材料导带电子的晶格散射过程.N型掺杂Si基Ge材料具有独特的双能谷(Γ能谷与L能谷)结构,它将通过以下两方面的竞争关系提高直接带导带底电子的占有率:一方面,处于Γ能谷的导带电子通过谷间光学声子的散射方式散射到L能谷;另一方面,处于L能谷的导带电子通过谷内光学声子散射以及二次谷间光学声子散射或者直接通过谷间光学声子散射的方式跃迁到Γ能谷.当掺杂浓度界于1017cm-3到1019cm-3时,适当提高N型掺杂浓度有利于提高直接带Γ能谷导带底电子占有率,进而提高Si基Ge材料直接带发光效率.国家自然科学基金青年基金(批准号:61604041);;福建省自然科学基金青年基金(基金号:2016J05147);;福建省教育厅2017年高校杰出青年科研人才培育计划项目;;福建工程学院校科研启动基金(批准号:GY-Z14073)资助的课题~

    阻断交感神经对青年和老龄小鼠小肠T淋巴细胞活性的影响

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    目的探究交感神经在青年和老龄小鼠中对小肠T淋巴细胞的免疫调控机制。方法选用健康的3月龄和18月龄的雄性昆明小鼠,腹腔注射六羟多巴胺,通过石蜡切片和HE染色观察上皮内淋巴细胞的数量,MTT法测定小肠T淋巴细胞的增殖,ELISA试剂盒测定小肠T淋巴细胞分泌IL-2、IL-4水平。结果阻断交感神经后,2个年龄组上皮内淋巴细胞数量均减少,老龄组尤为突出。青年小鼠T淋巴细胞增殖在处理后第5、10天出现下降,老龄小鼠在第3天至第15天均显著下降,其中第5天下降39.4%(P<0.01)。青年小鼠损毁交感神经后主要引起淋巴细胞分泌IL-4含量降低,而老龄小鼠主要引起IL-2降低。结论损毁交感神经可导致青年和老龄小鼠小肠T淋巴细胞活性下降,老龄组下降幅度大,恢复周期长

    大孔吸附树脂分离纯化龙胆药材中龙胆苦苷和马钱子苷酸的研究

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    目的:建立利用大孔吸附树脂对龙胆药材中龙胆苦苷和马钱子苷酸进行富集和分离纯化的方法。方法:采用加速溶剂萃取法对龙胆药材中两种有效成分进行高效提取,比较了D301,AB-8,D101,XDA-1四种大孔树脂对龙胆苦苷和马钱子苷酸的吸附性能,最终确定采用D301型大孔对脂对二者进行富集吸附,对其工艺参数进行优化,全程采用高效液相色谱进行目标化合物浓度检测。结果:化优后的工艺参数为:上样浓度:0.2 g/mL,最大上样量:0.25 g龙胆药材/g树脂,最佳静态吸附时间:8 h,采用8%和55%的乙醇溶液对龙胆苦苷和马钱子苷酸分别进行洗脱;龙胆苦苷和马钱子苷酸分别富集在8%和55%的乙醇洗脱液中,洗脱液浓缩后冷冻干燥,可得到纯度分别为74.3%和80.9%的粗产物,龙胆苦苷和马钱子苷酸的回收率分别为70.11%和67.82%。结论:此法效率较高,操作简便,即可用于实验室制备少量的难以购置的标准品,也可进行放大研究,用于工业生产。国家自然科学基金重点项目(20235020);; 青岛“2004将才计划”(04-3-JJ-11);; 共建生物医药研发测试中心(LS-05-KJZX-76)资

    Content of gentiopicroside and loganic acid in Radix gentianae and their fingerprints

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    To develop a HPLC-DAD-ESI-TOF/MS analysis method for the determination of gentiopicroside and loganic acid in Radix gentianae samples and for the research of their fingerprints.The samples were extracted using ASE for 10 min under 100 ℃ and 9.65 MPa,and divided into water phase and chloroform phase and analyzed them with HPLC-DAD-ESI-TOF/MS method respectively.Based on this method,the HPLC fingerprints of Radix gentianae were established.Comparing the spectrogram and mass spectrum of the chromatogram peak with the reference value,three compounds in water phase were identified as gentiopicroside,asafetida acid and loganic acid.There is no report of the compounds in chloroform phase.The content of gentiopicroside and loganic acid in samples of different groups were determined,separately.The fingerprints were compared by the software of the similarity evaluation system for chromatographic fingerprint.The water phase fingerprint congruence coefficients of samples from six different areas were above 0.90,however,the chloroform phase fingerprint congruence coefficients were within 0.62-0.99.This method can be used for determination of potent component in Radix gentianae and its quality control.Radix gentianae from different producing areas have the largest diversities,and the diversities embodied in the content of chloroform phase compounds.青岛“2004将才计划”(04-3-JJ-11);; 国家海洋局青年基金资助项目(2005602);; 崂山区政府区校共建生物医药研发测试中心资助(LS-05-KJZX-76)
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