月柿提取物体外抗氧化活性研究

目的以月柿提取物为原料,研究其对2,2-联苯基-1-苦基肼基(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基的清除能力,并测定其多酚类物质没食子酸的含量。方法检测波长为518 nm,反应时间为40 min条件下,以IC_(50)值(清除率为50%时,抗氧化剂的浓度值)作为抗氧化能力评价指标,并采用高效液相色谱法测定其没食子酸含量。结果月柿提取物对于DPPH自由基有良好的清除作用,其IC50值为0.1868 mg/mL,与常用抗氧化剂作用相当,且月柿提取物中没食子酸含量为1.65 g/kg。结论月柿提取物具有很强抗氧化活性,作为化妆品及功能性食品原料有广阔的开发前景。     

Integrated circuit and system design for renewable energy inverters

This study proposes that a novel integrated circuit (IC) and system design for renewable energy inverters can harvest renewable energy to power direct current (DC) and alternating current (AC) loads. In addition, an intelligent synthesis and management tool is developed to design the proposed system and to judge the system’s operational maintenance decisions. Finally, a renewable energy inverter’s information is posted to an online system. Users can obtain the proposed system’s information at any time and place. The accurate and superior performance of the proposed IC and system is confirmed by computer simulations and experimental results.     

高压共轨系统中的燃油温度变化及其影响

为说明高压流动燃油温度对喷油量的影响,进行了高压共轨系统中燃油温度变化及其影响研究,建立了燃油不同的发热和热交换数学模型,构建了高压泵、共轨管和喷油器的燃油温度模型,运用液压流体仿真软件AMESim构建高压共轨系统燃油热仿真计算模型;结合试验数据,验证了高压共轨系统燃油热模型的有效性,分析了不同燃油初始温度下不同部件出口燃油温度的变化。在高压泵转速分别为400r/min和1 600r/min时,高压油泵出口温度增加幅度分别约为4.5℃和23.3℃;在共轨管压力从55MPa增大到140MPa时,共轨管出口的燃油温度仅在35℃~55℃之间变化;在共轨压力为140MPa时,喷孔出口温度变化范围在90℃~110℃之间。燃油温度20℃、40℃时的压力变化较小,燃油温度0℃、60℃时的压力变化较大;在低共轨压力时燃油温度引起的喷油量变化大,高共轨压力时燃油温度引起的喷油量变化小。     

A Comprehensive Review of Genetically Engineered Mouse Models for Prader-Willi Syndrome Research

Prader-Willi syndrome (PWS) is a neurogenetic multifactorial disorder caused by the deletion or inactivation of paternally imprinted genes on human chromosome 15q11-q13. The affected homologous locus is on mouse chromosome 7C. The positional conservation and organization of genes including the imprinting pattern between mice and men implies similar physiological functions of this locus. Therefore, considerable efforts to recreate the pathogenesis of PWS have been accomplished in mouse models. We provide a summary of different mouse models that were generated for the analysis of PWS and discuss their impact on our current understanding of corresponding genes, their putative functions and the pathogenesis of PWS. Murine models of PWS unveiled the contribution of each affected gene to this multi-facetted disease, and also enabled the establishment of the minimal critical genomic region (PWScr) responsible for core symptoms, highlighting the importance of non-protein coding genes in the PWS locus. Although the underlying disease-causing mechanisms of PWS remain widely unresolved and existing mouse models do not fully capture the entire spectrum of the human PWS disorder, continuous improvements of genetically engineered mouse models have proven to be very powerful and valuable tools in PWS research.     

离子色谱法检测玩具材料中可迁移六价铬

文章建立了用离子色谱法检测玩具材料迁移液中六价铬的新方法。选用12.8 mmol/L NaCO3+4.0 mmol/L NaHCO3作为淋洗液,在530nm处用紫外可见检测器检测。实验表明,当进样量为2000μL时,对溶液中六价铬的检出限达到0.009μg/L。本方法灵敏度高、准确度好,对玩具材料的加标回收率在90%~110%之间,满足新指令对玩具材料中可迁移六价铬的检测要求。     

浓缩苹果汁高浓度有机废水处理工程的改造

对某果汁厂原废水处理工艺存在的问题进行了分析，提出了预处理／内循环厌氧反应器（IC）／UASB／普通活性污泥法的改进工艺。运行实践表明，出水水质优于《污水综合排放标准》（GB 8978-1996）一级标准，并实现了部分出水回用。     

An efficient small‐delay faults simulator based on critical path tracing

Testing for small‐delay defects (SDDs) has become an important component of integrated circuit testing. In this paper, an efficient small‐delay fault simulator, a hybrid method combining forward serial simulation and backward critical path tracing simulation for SDDs is proposed, which aims to determine the coverage of small‐delay defects for a given test set fast and accurately. In our proposed method, a unit delay model is employed, and reconvergent sensitization as well as hazard‐based detection is considered. Signal waveforms are expressed by bitmap data forms. In addition to providing an accurate result for fault simulation, the proposed simulator can well assist test generation. Experimental results demonstrate that the proposed simulator can further accelerate the simulation by one or two orders of magnitude compared with previous works. Copyright © 2014 John Wiley & Sons, Ltd.     

HDP介质淀积引起的新天线效应及损伤机理

超大规模集成电路设计和制造过程中,基于栅氧化层击穿的天线效应已得到广泛研究.从一个数模转换电路的漏电失效案例分析着手,利用电性分析、物理失效分析、工艺排查结合电路设计分析等手段,研究了一种与栅氧化层无关的天线效应.结果发现这种新的天线效应发生在高密度等离子体淀积介质层的工艺过程中,相邻金属互连长导线因不同的接地方式而具有不同的电势差,造成金属互连导线间的击穿和漏电.同时给出了该种天线效应的解决方案,该结果为半导体工艺设计规则制定提供了新的参考.     

数模混合高速集成电路封装基板协同设计与验证

介绍了数模混合高速集成电路(IC)封装的特性以及该类封装协同设计的一般分析方法.合理有效的基板设计是实现可靠封装的重要保障,基于物理互连设计与电设计协同开展的思路,采用Cadence APD工具以及三维电磁场仿真工具实现了特定数模混合高速集成电路(一款探测器读出电路)的封装设计与仿真论证,芯片封装后组装测试,探测器系统性能良好,封装设计达到预期目标.封装电仿真主要包含:封装信号传输通道S参数提取、电源/地网络评估,探测器读出芯片封装体互连通道设计能满足信号带宽为350 MHz(或者信号上升时间大于1 ns)的高速信号的传输.封装基板布线设计与基板电设计协同分析是提高数模混合高速集成电路封装设计效率的有效途径.     

片上电磁干扰感应阵列的设计与FPGA验证

测量EMI在片上电源分配网络中的二维分布,对研究集成电路的电磁抗扰性非常重要,能用于验证电磁抗扰模型的正确性。提出的片上电磁干扰感应阵列(OCEMISA)是一种测量EMI在电源分配网络上二维分布的测量方法。OCEMISA包含数个感应单元,在电源分配网络上产生开关噪声作为反馈信号,其频率各不相等,且只受局部电源电压的影响。用频谱分析仪经由电源引脚探测反馈信号,观察其特征频率随EMI的变化,计算感应单元所在位置EMI的电压分量,并采用FPGA验证OCEMISA的基本功能。