浅谈“材料学科综合实验”课程发展及改革

\"材料学科综合实验\"是近年来高等院校针对材料学科发展需求推出的一门本科生专业实验课程。该课程有效检验了学生理论学习情况和基础实验技能,同时进一步提升了本科生的综合专业素质。厦门大学\"材料学科综合实验\"以\"课题研究\"的形式授课,其授课内容及方法均与普通实验课程存在差异。针对近年来的课程发展过程中产生的影响授课质量的一些问题,提出了改革和发展的思路。结果表明,通过适当提高师/生比、简化课时考核形式及细化学生任务分工等形式,可有效提升教师的授课积极性及学生的能动性,显著改善授课质量

The Determination of Polycyclic Aromatic Hydrocarbons in Sediments with ASE/GC-MS

建立了用加速溶剂萃取技术提取含硫沉积物中痕量多环芳烃的可靠方法,优化了不同萃取剂,不同提取程序等萃取条件,研究了沉积物中的硫化物对色谱分离的影响。15种多环芳烃的检出限为0.09~1.34ng/g,相对标准偏差(RSD,n=6)为12.5%~23.9%,15种多环芳烃的低浓度加标回收在74%~138%之间。高浓度加标回收率除吲哚芘为62%外,其余都在80%~122%之间。基本上达到了痕量分析的要求。用该方法分析山东半岛近岸海域沉积物中多环芳烃的含量,测得15种PAHs的总量为273~579 ng/g。与其它地区沉积物中多环芳烃含量相比,属轻/中度污染。An accelerated solvent extraction method for the extraction of polycyclic aromatic hydrocarbons(PAHs) in sediments was developed.The extraction conditions such as extraction solvent and program were optimized.The effects of sulfide on chromatographic separation were studied.The detection limits for the fifteen PAHs were 0.09-1.34 ng/g,and the relative standard deviations(RSDs) ranged from 12.5% to 23.9%.The recoveries of high level concentration ranged from 62% to 122% and those of low level concentration ranged from 74%-138%.The contents of PAHs in sediment samples collected in the coastal regions off the Shandong peninsula,China were analyzed by this method.The PAHs in these samples ranged from 273 ng/g to 579 ng/g.Overall,the PAHs levels were comparable to those reported in the literature for sediment samples collected from similar environments around the world.国家高技术研究发展计划(863)基金项目(2003AA635180);; 青岛科技将才计划基金项目(04-3-J.J-11

高精度SC PIPELINED ADC预放大锁存比较器的分析与设计

提出了一种应用于开关电容流水线模数转换器的CMOS预放大锁存比较器。比较器采用了交叉耦合负载、PMOS/NMOS比例优化和电容中和技术。该结构大幅提高了比较器的速度并有效抑制了回馈噪声,减小了失调电压,可以作为Flash ADC应用于高精度开关电容流水线ADC

固相微萃取-气相色谱-质谱联用测定海水和沉积物间隙水中的痕量多环芳烃

建立了固相微萃取(SPME)与气相色谱-质谱(GC-MS)联用同时测定海水中16种多环芳烃的分析方法,研究了萃取时间、盐度条件的影响．同时用SPME的方法研究了海水中的溶解有机物(DOM)对多环芳烃萃取的影响．计算出不同DOM浓度下多环芳烃KDOM与KOW的关系: CDOM=5 mg／L时,logKDOM=0．7944KOW+0．773(R2=0．91)．CDOM=10 mg／L时,logKDOM= 0．7905KOW+0．668(R2=0．97);CDOM=30 mg／L时,logKDOM=0．714KOW+1．0407(R2=0．91)．该法对16种多环芳烃的检出限为0．1-3．5 ng／L,相对标准偏差(RSD,n=5)为4％-23％．用该法分析海洋环境中的痕量多环芳烃,16种多环芳烃的平均回收率为88.2±20．4％,方法快速、灵敏、简单,适用于快速分析海水和沉积物间隙水样中的痕量多环芳烃．国家高技术研究发展计划(863)(批准号:2003AA635180);; 青岛科技将才计划(批准号:04-3-JJ-1)资助项

Research Progress of Metal Material Liquid Forming Technology

随着汽车工业的迅速发展以及市场竞争对铸件质量要求的提高,推动了金属材料液态成型技术发展。从20世纪70年代压铸技术的广泛运用,到90年代挤压铸造技术的不断完善,随后挤压压铸技术不断创新,使液态成型技术向多学科渗透融合发展,应用领域不断拓展,铸件用量逐年上升。重点介绍了压铸、挤压铸造、挤压压铸这三种重要的成型技术发展以及取得的最新成果。With the rapid development of auto industry and the market competition on the increase of the requirement of the casting quality,the development of metal material liquid forming technology was promoted.From the extensive use of the die casting technology in the nineteen seventies to constant maturity of the 90's the squeeze casting technology,and then the continuous innovation of squeezing die casting,the liquid forming technology for multidisciplinary permeated and developed,application area continued to expand,and casting quantities increased year by year.The development and the latest achievements of three kinds of important forming technologies(die casting,squeezing casting and squeezing die casting) were mainly introduced.贵州省(贵阳市)工业攻关项目(黔科合GY字[2012]3004;筑科合同[2012101]2-13号

Analysis and design of preamplifier-latch comparator for high accuracy switched-capacitor pipelined ADC

提出了一种应用于开关电容流水线模数转换器的CMOS预放大锁存比较器。比较器采用了交叉耦合负载、PMOS/nMOS比例优化和电容中和技术。该结构大幅提高了比较器的速度并有效抑制了回馈噪声,减小了失调电压,可以作为flASH AdC应用于高精度开关电容流水线AdC。To be compatible with switched capacitor pipelined ADC,a CMOS preamplifier-latch comparator is designed and well analyzed for high speed,low kick-back noise and low mismatch offset.The cross-coupled load,capacitor neutralization and the optimizing ratio of PMOS/NMOS are adopted in the comparator.Since the proposed architecture is effective for achieving,the comparator has been used in high accuracy switched-capacitor pipelined ADC as Flash ADC.厦门市科技计划项目(3502Z20093002);福建省高校产学合作科技重大项目(2010H6026

高精度SC PIPELINED ADC预放大锁存比较器的分析与设计

提出了一种应用于开关电容流水线模数转换器的CMOS预放大锁存比较器。比较器采用了交叉耦合负载、PMOS/NMOS比例优化和电容中和技术。该结构大幅提高了比较器的速度并有效抑制了回馈噪声,减小了失调电压,可以作为Flash ADC应用于高精度开关电容流水线ADC

我国科技期刊媒体融合制约因素及突破路径探析

目的 分析并探讨我国科技期刊媒体深度融合的制约因素及突破路径。方法 通过文献调研、案例分析与对比,基于政策导向、专家意见及期刊现实情况,对期刊的发展现状进行归纳与分析。结果 系统梳理了制约我国科技期刊媒体融合的4个主要因素,提出可从5个方面进行融合转型升级路径探索。 结论 制约我国科技期刊媒体融合的因素主要包括管理机制与相关政策、人才与团队构建、先进技术与内容产品、发展资金等。要实现科技期刊与新媒体的深度融合,应坚持&ldquo;五位一体&rdquo;的融合路径:坚持正确的理念、思维及意识;组建&ldquo;领军人才+专才&rdquo;的团队或联盟;构建立体化网络平台与全媒体产业链,形成传播媒体矩阵;用技术外包实现近期内容创新,同时加大技术自主研发力度,以掌握深度融合的主动权;管理运营要注重顶层设计、资源有效配置、利用最大化,促进科技期刊事业的可持续发展。</p

Down-regulation of TSPO expression doesn't affect the productions of TNF-α,IL-1β and IL-6 in LPS-stimulated BV-2 microglia

目的研究相对分子质量(Mr)18 000转运蛋白(TSPO)基因表达下调对脂多糖(lPS)诱导bV-2小胶质细胞分泌Tnf-α,Il-1β和Il-6的影响。方法以rnA干扰技术建立TSPO基因表达下调的细胞模型,实时荧光定量PCr(QrT-PCr)和WESTErn blOT法检测转染TSPO SIrnA bV-2细胞TSPO MrnA及蛋白水平表达的效果;用QrT-PCr法检测TSPO基因下调后小胶质细胞bV-2在lPS作用下分泌Tnf-α、Il-1β和Il-6的MrnA水平表达的情况;ElISA检测TSPO基因下调小胶质细胞bV-2在lPS作用下分泌Tnf-α、Il-1β和Il-6的蛋白水平表达的变化。结果成功建立了TSPO基因下调的细胞模型,稳定表达TSPO SIrnA细胞的TSPO MrnA和蛋白水平表达均明显下降,TSPO基因下调后bV-2细胞在lPS作用下分泌Tnf-α、Il-1β和Il-6的量无变化。结论下调TSPO的表达对lPS刺激引起的小胶质细胞Tnf-α、Il-1β和Il-6的分泌无明显影响。Objective To evaluate the effect of translocator protein( TSPO,Mr18 000) on the productions of TNF-α,IL-1βand IL-6 in lipopolysaccharide( LPS)-stimulated BV-2 cells.Methods RNA interference technique was used to decrease TSPO expression in BV-2 cells.Western blotting was performed to assess the level of TSPO protein in BV-2 cells transfected with TSPO siRNA.Then the mRNA and protein levels of TNF-α,IL-1β,and IL-6 were measured in LPS-stimulated BV-2 cells by real-time quantitative PCR( qRT-PCR) and ELISA,respectively.Results The level of TSPO protein obviously decreased in BV-2 cells transfected with TSPO siRNA.However,knockdown of TSPO had no effect on the productions of TNF-α,IL-1βand IL-6 in LPS-stimulated BV-2 cells.Conclusion Down-regulated TSPO is not directly involved in regulating TNF-α,IL-1βand IL-6 productions induced by LPS in microglia.国家自然科学基金(81071182); 福建省医学创新项目(2009-CXB-46); 厦门大学生命科学学院细胞生物和肿瘤工程教育部重点实验室开发基金(2009101); 福建医科大学非直属附属医院科研发展专项基金(2008031