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991.
体积和结构差异较大的铝合金零件在同一模具中压铸成形即一模多件时,会出现各自不同的压铸缺陷。对此,从浇注、工艺、模具等方面分析了不同缺陷产生的原因,提出了改进措施。结果表明,差异较大的铸件在同一模具中压铸生产时,要避免压射参数的冲突,平衡模具温度是获得高品质压铸件的关键。 相似文献
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介绍了天津鞍钢天铁酸洗冷轧线的控制架构及SDH的队列管理规则,解释了SDH的功能,从SDH的缓冲区管理、接口、诊断、SDH缓冲区的检索等多个方面进行了详细的分析,并给出了具体应用实例,对于理解酸洗连轧设定值数据处理及管理具有一定的参考价值。 相似文献
996.
Nursiati Mohamad Taridi Nazirah Abd Rani Azian Abd Latiff Wan Zurinah Wan Ngah Musalmah Mazlan 《Lipids》2014,49(9):855-869
Little is known about the effect of vitamin E on brain function. Therefore, in this study we evaluated the effect of tocotrienol rich fraction (TRF) on behavioral impairment and oxidative stress in aged rats. Thirty-six male Wistar rats (young: 3-months-old; aged: 21-months-old) were treated with either the control (olive oil) or TRF (200 mg/kg) for 3 months. Behavioral studies were performed using the open field test and Morris water maze (MWM) task. Blood was taken for assessment of DNA damage, plasma malondialdehyde (MDA) and vitamin E, and erythrocyte antioxidant enzyme activity. Brains were also collected to measure vitamin E levels. Results showed that aged rats exhibited reduced exploratory activity, enhanced anxiety and decreased spatial learning and memory compared with young rats. DNA damage and plasma MDA were increased, and vitamin E levels in plasma and brain were reduced in aged rats. Aged rats supplemented with TRF showed a markedly reduced level of anxiety, improved spatial learning and memory, reduced amount and severity of DNA damage, a reduced level of MDA, and increased levels of antioxidant enzyme activity and plasma/brain vitamin E compared with age-matched controls. In conclusion, TRF supplementation reverses spatial learning and memory decline and decreases oxidative stress in aged rats. 相似文献
997.
Photoacoustic Imaging Guided Near‐Infrared Photothermal Therapy Using Highly Water‐Dispersible Single‐Walled Carbon Nanohorns as Theranostic Agents 下载免费PDF全文
Daiqin Chen Chao Wang Xin Nie Shumu Li Ruimin Li Mirong Guan Zhuang Liu Chunying Chen Chunru Wang Chunying Shu Lijun Wan 《Advanced functional materials》2014,24(42):6621-6628
The poly(maleic anhydride‐alt‐1‐octadecene‐poly(ethylene glycol)) (C18PMH‐PEG) modified single‐walled carbon nanohorns (SWNHs) are designed with high stability and biocompatibility. The as‐prepared SWNHs/C18PMH‐PEG not only can serve as an excellent photothermal agent but also can be used as a promising photoacoustic imaging (PAI) agent both in vitro and in vivo due to its strong absorption in the near infrared (NIR) region. The PAI result reveals that the SWNHs/C18PMH‐PEG possesses ultra long blood circulation time and can significantly be accumulated at the tumor site through the enhanced penetration and retention (EPR) effect. The maximum accumulation of SWNHs/C18PMH‐PEG at tumor site could be achieved at the time point of 24 h after intravenous injection, which is considered to be the optimal time for the 808 nm laser treatment. The subsequent photothermal ablation of tumors can be achieved without triggering any side effects. Therefore, a PAI guided PTT platform based on SWNHs is proposed and highlights the potential theranostic application for biomedical uses. 相似文献
998.
Zifang Zhao Shuai Wang Fang Wan Zhiwei Tie Zhiqiang Niu 《Advanced functional materials》2021,31(23):2101302
The self-assembly of large-area MXene films is the main step to realize their applications in various energy storage devices. However, the scalable self-assembly of flexible thin MXene films with high conductivity as well as excellent mechanical and electrochemical properties is still a challenge. Herein, a synchronous reduction and self-assembly strategy to fabricate flexible MXene films is developed, where MXene films are synchronously reduced and self-assembled on the Zn foil surface. Furthermore, the self-assembly of MXene films can be scaled up by controlling the area of Zn substrates. By adjusting the patterns of Zn substrates, the interdigital MXene patterns can also be obtained via a selectively reducing/assembling process. The resultant MXene films demonstrate high electrical conductivity, large specific surface area, and excellent mechanical properties. Thus they can serve as the electrodes of flexible supercapacitor devices directly. As a proof of concept, flexible sandwich and microsized supercapacitors are designed based on the above MXene film electrodes. Both sandwich and microsized supercapacitors display stable electrochemical performance under various bending states. This study provides a route to achieve large-area MXene-based films or microsized structures for applications in the field of energy storage. 相似文献
999.
计算机模拟计算在各种类型加速器的设计中起着很重要的作用。例如,计算机模拟很快就可以确定加速器各部件的最佳工作参数和所需要的光学条件,使一台加速器复杂的束流输运系统设计变成简单的工作。TRANSPORT程序是当今世界上关于束流输运计算的最优秀程序之一。但是,该程序不能进行静电加速器离子光学系统的计算,也不能作直线加速器的粒子动力学计算。为此从北京大学引进了LEADS程序,它不仅具有TRANSPORT程序的优点,还克服了其不足。对含有聚束(脉冲束流)系统的加速器粒子动力学进行模拟是LEADS程序的新特色。实验中用LEADS程序模拟了200keV直流/脉冲中子发生器束流输运过程,得到了横向相图、纵向相图和束包络图。还用LMOV程序计算和验证了聚束系统,束流脉冲波形图和实验结果比较接近。 相似文献
1000.
为解决现代建筑施工复杂,工程量大所导致的数据冗杂、管理困难等问题,本文研究了基于BIM信息协同管理平台,梳理了其结构框架和平台功能。平台通过模型管理、现场管理、指挥管理三个模块,能够对工程进行有效的协同管理,提升管理水平和管理效率。 相似文献