宁波国际会展中心空调冷却塔改进措施

针对冷却塔降温效果较差问题,采取了重新码放填料、调整风机转速比、增加风机叶片数量、加宽叶片直径等改进措施。多次的试运行结果表明改进措施是可行的。     

cPCN-Regulated SnO2 Composites Enables Perovskite Solar Cell with Efficiency Beyond 23％

Efficient electron transport layers(ETLs)not only play a crucial role in promoting carrier separation and electron extraction in perovskite solar cells(PSCs)but...     

MEMS微型双稳态电磁继电器的设计

本文利用通电平面螺旋线圈产生磁场特点,采用镜像绕制以及并联连接双线圈的方法,研制了一种快速低功耗MEMS微型双稳态继电器结构,其尺寸约为3mm*4.5mm*1.5mm,文中着重分析其工作原理和过程.经过分析,该继电器在通电电流80～120mA时,开关时间约在0.1ms～0.2ms之间,因此,其具有体积小、开关速度快、低功耗等优点,并且易于集成和阵列,适用于能源有限并且可靠性要求高的微型航天器以及便携设备中.     

某型柴油机增压系统概述

增压技术能提高柴油机功率和改善经济性能,某型柴油机增压技术非常先进,是该公司核心技术之一。本文分析了其增压系统的特点,并介绍了增压器的特殊功能和先进结构。     

利用TSUPREM-4对低压VDMOS进行虚拟制造

介绍了低压VDMOS的结构和各个参数及相互间的关系,并按TSUPREM-4工艺仿真软件的工艺流程顺序给出了各步工艺的设计思路、方法、注意事项。对外延层厚度进行了计算,并用该软件实现了耐压55 V,导通电阻11 MΩ的低压VDMOS器件结构的工艺设计,绘出了仿真结构图。     

密度泛函理论和从头计算法研究环戊二烯衍生物气态酸度及其取代基效应

用B3LYP／6-311G(2df,p)／／B3LYP／631 G*和MP2／6-311G(d,p)／／B3LYP／6-31 G*方法准确地预测了9个系列的环戊二烯衍生物(R=CN,CF3,CHO,C283,F,SiH3,H,CH3,OH,NH2)的C-H键的酸度。环戊二烯衍生物气态酸度的范围从284.9 kcal／mol (化合物5a)到357.24kcal／mol(化合物7j),分析取代基的电性、数量以及位置的影响得到了9个QSAR方程。这些数据有助于我们设计以及合成一些有机酸,并有助于深刻理解相关反应中环戊二烯衍生物的性质。     

基于eM-Plant和分支定界算法的动态加工车间送料路径仿真与优化

利用了优秀的仿真软件和经典的优化算法理论,对现实中的动态车间送料路径进行仿真优化,并给出了结果.     

切流反转式旋风除尘器排气管的改进

除尘效率和压力损失是旋风除尘器最重要的两个性能指标,而排气管的结构对压力损失又有很大的影响.通过改善上排气管的形状和增加下排气管,可达到在不降低除尘效率的情况下,降低除尘器的压力损失.     

Essential oil composition and antimicrobial activity of Sphallerocarpus gracilis seeds against selected food-related bacteria

Sphallerocarpus gracilis from China is a little-investigated edible and medicinal plant. In the present study, the essential oil composition from S. gracilis seeds was investigated by GC and GC–MS. A total of 34 compounds representing 94.69% of the essential oil were tentatively identified. The main constituents were p-cymene (17.42%), γ-terpinene (25.58%) and α-asarone (33.12%). The antimicrobial activity, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) of the essential oil from S. gracilis seeds were evaluated against eight Gram-positive bacteria (Listeria monocytogenes, Staphylococcus aureus, Staphylococcus epidermidis, Micrococcus luteus, Bacillus megaterium, Bacillus cereus, Bacillus coagulans and Bacillus subtilis), four Gram-negative bacteria (Salmonella enteritidis, Salmonella typhimurium, Klebsiella pneumoniae and Escherichia coli) and one fungus (Aspergillus niger). Results revealed that the essential oil from S. gracilis seeds exhibited significant in vitro antimicrobial property. Among all the tested microorganisms, the essential oil showed the strongest inhibitory effect against K. pneumoniae, whereas no inhibitory effect was found against L. monocytogenes and A. niger. Additionally, scanning electron microscopy (SEM) was used to observe morphological changes of bacteria treated with the essential oil from S. gracilis seeds. SEM observations confirmed the physical damage and considerable morphological alteration to the tested microorganisms treated with the essential oil. The data of this study suggests that the essential oil from S. gracilis seeds has great potential for application as a natural antimicrobial agent to preserve food.