多交联体系PU/分子筛复合材料的制备及表征

以聚酯多元醇(PEA)、2,4-甲苯二异氰酸酯(TDI-100)和13X分子筛为原料,采用预聚法制备PU/13X分子筛预聚体,再将预聚体分成两部分,分别与不同比例的扩链剂(MOCA)混合反应,然后将两种体系混合后浇铸成型,制备出多交联体系PU/13X分子筛复合材料.对其力学性能、耐溶剂性能进行了测试并与聚氨酯材料的性能进行了比较.结果表明,多交联体系PU/13X复合材料的耐撕裂性能明显提高,拉伸性能稍有下降;通过DMA、DSC测定,表明多交联体系PU/13X复合材料的玻璃化转变温度降低,微相分离更好,阻尼性能下降;分子筛可以改善多交联体系PU/13X复合材料的耐溶剂性能.     

Trusted Integrated Circuits: The Problem and Challenges

Hardware security has become more and more important in current information security architecture. Recently collected reports have shown that there may have been considerable hardware attacks prepared for possible military usage from all over the world. Due to the intrinsic difference from software security, hardware security has some special features and challenges. In order to guarantee hardware security, academia has proposed the concept of trusted integrated circuits, which aims at a secure circulation of IC design, manufacture and chip using. This paper reviews the main problems of trusted integrated circuits, and concludes four key domains of the trusted IC, namely the trusted IC design, trusted manufacture, trusted IP protection, and trusted chip authentication. The main challenges in those domains are also analyzed based on the current known techniques. Finally, the main limitations of the current techniques and possible future trends are discussed.     

A Study on the Friction and Wear Behavior of PTFE Filled with Acid Treated Nano‐Attapulgite

Summary: A solid lubricant composite material was prepared by compression molding PTFE and acid treated nano‐attapulgite. The friction and wear tests were performed on a block‐on‐ring wear tester. Scanning electron microscopy (SEM), energy‐dispersive X‐ray spectrometer (EDS) and DSC were utilized to investigate material microstructures and examine modes of failure. Experimental results showed that there was no significant change in coefficient of friction, but the wear rate of the PTFE composite was orders of magnitude less than that of pure PTFE. Acid treated nano‐attapulgite was superior to untreated nano‐attapulgite in enhancing the wear resistance of PTFE. Moreover, the wear resistance of the composite increased monotonically with increasing treated attapulgite concentration. Investigation of transfer film and analysis of debris for PTFE and its composite showed that acid treated nano‐attapulgite filled to PTFE could facilitate formation of transfer film on the steel ring surface and inhibit breakage of PTFE molecular chain. The PTFE composite with higher heat absorption capacity exhibited improved wear resistance. Furthermore, the steel ring counterface abrasion was not found.

Effect of load on the wear rate of PTFE and its composites.     

腐植酸物质对盐碱化中低产田土壤理化性质及玉米影响的研究

通过田间试验探讨了复合改良制剂、草炭、风化煤等腐植酸类物质施用对盐碱化中低产田土壤理化性质及生长作物的影响，结果表明：复合改良制剂、草炭、风化煤施用对土壤理化性质均有积极的影响，与对照相比达到显著水平。玉米产量的方差分析表明，复合改良制剂处理与草炭、风化煤等处理差异显著，与对照差异极显著，增产率均达到30．67％以上。     

高强度聚乙烯纤维绳索的制备研究

研究了纤维的捻度及浸胶处理对超高相对分子质量聚乙烯 (UHMWPE)纤维力学性能及摩擦磨损性能的影响。结果表明 ,UHMWPE纤维的断裂强力随着纤维捻度的增加而减小 ,纤维浸胶处理后的断裂强力增大 ;当UHMWPE纤维中改性氯丁胶粘剂或聚氨酯胶粘剂的含量为 6%时 ,其断裂强力分别增加 17.2 %或 13 .9% ,聚氨酯胶粘剂处理过的UHMWPE纤维的耐摩擦磨损性能最好。     

施釉机器人静力学分析的研究

根据6自由度施釉机器人的终端受力，利用雅可比矩阵，求解出各转动关节在稳定平衡状态下的受力和所需的驱动力矩，为设计施釉机器人确定各转轴的电机及其他动力元件提供了可靠的依据。     

煤矸石对硅酸盐水泥水化历程的影响

从强度、反应程度、孔溶液碱度和SEM等方面,研究了煤矸石作为水泥辅助胶凝材料的水化情况,并与Ⅱ级粉煤灰进行比较。试验结果表明:煤矸石发生火山灰反应时间比粉煤灰早,且发生火山灰反应所需的碱度值比粉煤灰低;掺煤矸石水泥水化样的早期抗压强度比粉煤灰水泥水化样低,但7d到28d强度增长速率明显大于相同掺量的粉煤灰水泥,相同28d抗压强度的条件下,煤矸石掺量比粉煤灰的掺量高10%。     

Variability of light absorption properties in optically complex inland waters of Lake Chaohu,China

Absorption coefficients of phytoplankton, colored detrital matter (CDM), non-algal particles (NAP), colored dissolved organic matter (CDOM), and their relative contributions to total non-water absorption (a_t ? w) are essential variables for bio-optical and radiative transfer models. Light absorption properties showed large range and variability sampled at 194 stations throughout Lake Chaohu between May 2013 and April 2015. The a_t ? w was dominated by phytoplankton absorption (a_ph) and NAP absorption (a_d). The contribution of CDOM absorption to a_t ? w was lower than 30%. Phytoplankton and NAP were the primary sources of spatial and vertical variability in absorption properties. Light absorption by CDOM, though significant in magnitude, was relatively constant. CDM absorption (a_dg) was dominated by NAP. The spatial variation of the absorption coefficients from each of the optically active constituents were driven by several main inflow rivers in the western and middle part of Lake Chaohu. Algal blooms and bottom resuspension contributed to vertical variability as observed by phytoplankton and NAP profiles. Specific absorption of phytoplankton had significant spatial and seasonal variations without vertical variation. The spectral slope of absorption showed no significant spatial variability (p > 0.05). Variations of absorption affected different ranges of remote sensing reflectance (R_rs) spectrum, thereby increasing the difficulty of applying the remote sensing algorithm in optically complex waters. Parameters and relationships presented in this study provide useful information for bio-optical models and remote sensing of lakes similar to Lake Chaohu in terms of optical properties.     

我国塑料助剂生产现状与发展趋势

简述了我国塑料助剂生产现状、市场供需及发展方向，“十五”期间我国塑料助剂工业发展势头强劲，目前已基本满足我国塑料工业的发展需求，但是在品种和产品质量等方面与国外先进水平相比仍有较大的差距。提出了提高我国塑料助剂国际市场竞争力的措施。