Selective deposition on block copolymer film by thermal evaporation of silver

Selective deposition of Ag onto nanostructured block copolymer film template of poly(ethylene oxide) and poly(methacrylate) with azobenzene mesogen (PEO-b-PMA(Az)) has been done by thermal evaporation technique. A hexagonally arranged pattern or ordered strip structure of the PEO nanocylinders dispersed in the PMA(Az) matrix appears on the pure copolymer film surface after thermal annealing at 140 °C or 110 °C, respectively. Atomic force microscopy confirms that the deposited Ag atoms prefer to wet PMA(Az) matrix domains on the film surface, and finally aggregate into discrete nanoparticles in both cases. An ordered porous metallic layer is created on the hexagonally patterned copolymer template surface due to the preferential interaction of Ag toward the PMA(Az) phase. Alternatively, ordered array of metallic chains is formed on the template featured with strip structure. While the nominal layer thickness of the deposited Ag is 50 nm, the ordered metallic nanostructure disappears, indicating the host copolymer template cannot guide the spatial distribution of the deposited metal any more.     

发酵十字花科蔬菜中硫代葡萄糖苷代谢研究进展

硫代葡萄糖苷（简称硫苷）是十字花科蔬菜中一类重要的次生代谢物。在蔬菜发酵过程中，硫苷被代谢为异硫氰酸盐等活性产物，这些代谢产物具有抗氧化、抗癌、调节肠道菌群等多种生理功能。乳酸菌发酵对硫苷的代谢机制包括促进硫苷从蔬菜中释放，以及使其发生降解，且代谢作用既与乳酸菌种属相关，也与发酵体系的盐含量、金属离子、pH值以及蔬菜加热预处理相关。通过总结梳理发酵蔬菜硫苷代谢研究进展，并解析影响因素，为提高发酵蔬菜中活性硫苷代谢产物含量，提升发酵蔬菜的健康效应提供理论指引。     

40000m~3/h空分设备变负荷操作及过程优化

主要探讨了冶金用制氧机组如何适应炼钢炼铁需求量的不断变化,减少氧气放散。通过对40000 m3/h制氧机组进行变负荷操作以及对操作过程的优化,实现了节能降耗、减少氧气放散的目的。     

Effects of salt-induced changes in protein network structure on the properties of surimi gels: computer simulation and digestion study

Surimi is considered a new base ingredient in special dietary foods because of its excellent gel formation properties and nutritional value. Cross-linked network structures are the basis for the formation of protein hydrogels. In this work, protein network structure induced by NaCl was investigated to evaluate its effects on texture property and digestibility of surimi gels. Micro-protein frameworks were investigated by scanning electron microscope combined with computer simulation, which indicated that the network structure became fine and smooth as a result of salt treatment. The digestibility of surimi with NaCl was higher than that of blank samples in simulated gastric juice in first 30 min, whereas the digestibility showed no significant difference (P = 0.257) in intestinal juice after 180 min. This work aids in understanding of the contribution of salt to the mechanism of surimi gels formation, and its effects on digestion, thus supporting potential applications in special dietary food.     

Origin of (103) plane of ZnO films deposited by RF magnetron sputtering

(103) diffraction has been observed at X-ray diffraction (XRD) patterns of columnar Al-doped ZnO (AZO) thin films grown along [001] direction deposited by RF magnetron sputtering. As the X-ray incidence angle employed in grazing incidence XRD increased, the ratio of I(103)/I(002) became smaller. Similar results have also been observed when the films became thicker, which induced that the origin of the (103) diffraction might be related to the surface structure of AZO film. The surface structure could be affected by the movement or diffusion of atoms at the final stage of the sputtering process.     

GB 28481-2012《塑料家具中有害物质限量》标准解读

2012年颁布实施的GB 28481-2012《塑料家具中有害物质限量》是一部针对家具中有毒有害物质测定的限量标准,标准的出台完善了我国家具有毒有害物质检测方法标准体系。本文对标准的邻苯二甲酸酯、重金属、苯并{a}和多环芳总量、多溴联苯和多溴联苯醚等有毒有害物质前处理和检测方法以及同分异构体的限量值进行了较详细的介绍,并对确立技术指标的依据和来源进行了分析,为该标准发布后得以更好地贯彻实施提供了可行的指导和参考。     

退火时间对FeCuSiBAl纳米晶/非晶复合材料的纳米压痕力学行为的影响

采用充氩气的电弧熔炼加单辊甩带法制备一种FeCuSiBAl非晶合金,然后在831K下恒温退火,研究退火时间对非晶合金的显微组织与纳米压痕力学行为的影响。结果表明,FeCuSiBAl非晶合金退火时在非晶基体中产生纳米晶,纳米晶化程度随退火时间延长而增加。在60min退火时间内,合金的硬度随退火时间延长而增大,退火时间超过60min后,硬度开始下降。退火以及降低载荷都导致合金的弹性模量增大。     

Spatio-temporal analysis of precipitable water vapour over northwest china utilizing MERSI/FY-3A products

Northwest China is considered as the arid and semi-arid temperate continental climate, where the precipitation is closely related to precipitable water vapour (PWV) content. In this paper, the Medium-Resolution Spectral Imager (MERSI) water vapour products were first used to study the spatial and temporal characteristics of water vapour over Northwest China, which were developed by the National Satellite Meteorological Center of China from the Chinese second-generation polar orbit Meteorological Satellite Fengyun 3A (FY-3A). In order to utilize the MERSI water vapour products, the MERSI 5 min water vapour product is compared respectively with global positioning system (GPS), Aerosol Robotic Network (AERONET) and Radiosonde water vapour data in situ datasets. The results show that the water vapour values of the MERSI product are a slightly lower than referenced data, and the accuracy of MERSI product compared with GPS water vapour is the most agreeable, with a mean absolute percentage error (MAPE) of 22.83%. The PWV content displays a typical spatial distribution pattern in Northwest China that it is the highest in the southeast, the second for the northwest and the lowest in the south-centre. The water vapour content over each province in a descending order is Shaanxi, Ningxia, west of Inner Mongolia, Xinjiang, Gansu and Qinghai. The seasonal variation of water vapour content over Northwest China appears to be lowest in winter, followed by spring, then for autumn, and highest in summer. The PWV content of each province in Northwest China shows the periodic inner-annual variation, that is, the PWV content is lowest in January, and gradually increases with time till it peaks in July, and then decreases monthly afterwards, which agrees with the quadratic polynomial model by months. The standard deviation of the water vapour content in summer is 0.533–1.027 mm, while that in winter is 0.262–0.527 mm.