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11.
采用剥离测试方法来表征制得的玻璃纤维增强建筑用聚乙烯树脂复合材料的界面黏结强度,并对其进行红外光谱、接触角、微观组织测试与分析。研究结果表明:采用浸润剂处理可以使玻璃表面生成新基团;浸润剂能够提高玻璃表面接触角,从而更易与树脂形成浸润状态,由此改善玻璃和树脂的界面结合状态,实现界面黏结特性的显著优化。在剥离测试中发现经浸润剂处理后,玻璃可以和树脂之间形成更强的界面结合作用;树脂从玻璃表面发生剥离之后,形成了光滑的玻璃片,同时还有部分纵横交错的划痕。 相似文献
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Georgia N Tomara Panagiota K Karahaliou Dimitris L Anastassopoulos Stavroula N Georga Christoforos A Krontiras Jozsef Karger‐Kocsis 《Polymer International》2019,68(5):871-885
Polyamide‐6 (PA‐6)/boehmite alumina (BA) nanocomposites were prepared via direct melt compounding. Structural, thermal and dielectric properties of ‘as‐received’ (including moisture) and ‘dried’ (thermally treated) specimens were examined. The BA nanofiller was homogeneously dispersed in the PA‐6 matrix. XRD and FTIR revealed that crystallization of PA‐6 in the γ phase was favoured over α phase with increasing BA content. The crystallinity index (CI) and the percentage of α and γ phases were also evaluated. Dried specimens exhibited a lower CI than as‐received specimens while the CI decreased with the addition of filler. Broadband dielectric spectroscopy revealed the presence of γ, β and α relaxations, the Maxwell–Wagner–Sillars effect and the contribution of conductivity relaxation in the as‐received samples. The drying procedure unmasked a double feature of both β and α modes. The results of the complementary techniques were analysed and the effects of moisture and/or the incorporation of BA nanofiller on the microstructure of the PA‐6 matrix are disclosed. © 2019 Society of Chemical Industry 相似文献
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This paper describes the characteristics of a new CAD tool that enables the creation of layout libraries of selected analog modules. This Analog Modules Generator (AMG) automatically creates multiple layout versions of two commonly used analog structures: the differential pair and arrays of series-connected or stacked devices, for the subsequent generation of layout libraries. Based on the number of devices and rows defined by the user for the layout implementation, the tool validates all possible implementations, which are later saved in a database. Additionally, an extraction process can be optionally executed over all the layout views saved in the database. The AMG generates several reports with all the characteristics of the implemented layouts, including area and parasitic components, facilitating further statistical processing. We describe the features and capabilities of the proposed AMG tool, and several test cases are presented. Results show that suitable layout implementations can be achieved by layout and circuit designers in a very reduced amount of time. 相似文献
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Yongqian Shen Yupeng Wei Jiqiang Ma Qinglin Li Jian Li Wenjie Shao Pengze Yan Guowei Huang Xueyan Du 《Ceramics International》2019,45(3):3313-3324
The nickel-carbon nanofibers (Ni-C NFs) were fabricated by the electrospinning of poly(vinyl alcohol) (PVA) and nickel acetate tetrahydrate (NiAc) solution precursor with succedent PVA pyrolyzation and calcination process. The microwave absorption performance and electromagnetic (EM) parameters of the NFs were researched over the frequency range of 2.0–18.0?GHz. Both the impedance matching and EM wave absorption properties of the Ni-C NFs were improved by changing the carbonization temperature. The effect of graphitization degree on reflection loss (RL) and the possible loss mechanisms were directly displayed in the comparative study of each sample. The optimal RL value of ??44.9?dB and an effective frequency bandwidth of 3.0?GHz under a thickness of 3.0?mm can be reached by a sample calcined at 650?°C. These lightweight Ni-C NFs composites can be promising candidates for EM wave absorbers due to the combination of multiple loss mechanisms, nano-size effect and good impedance matching between Ni nanoparticles and CNFs. 相似文献
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采用纳滤分离技术以雪莲果为原料纯化低聚果糖,通过Box-Behnken中心组合设计(CCD)及响应面分析(RSM)建立预测低聚果糖纯度的二次多项数学模型,优化分离纯化工艺。结果表明:操作压力0.15 MPa,循环流量5.3 mL/min,pH值2.7时,纯化倍数为5,实际低聚果糖纯度为95.1%,达到P级产品标准。通过应用HPLC-MS、IR、1H NMR及13C NMR等对雪莲果低聚果糖组分的纯度、组成、结构进行表征,结果表明:分离纯化得到的雪莲果低聚果糖由蔗果三糖、蔗果四糖和蔗果五糖组成,纯度为95.1%,平均包含5个果糖单元,主要是由β-呋喃构型的果糖组成。 相似文献
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K. Balamurugan S. Sankar U. S. Hareesh K. G. K. Warrier 《Materials and Manufacturing Processes》2018,33(4):405-413
In this work, lanthanum phosphate with a 20% yttria (LaPO4/Y2O3) composite prepared by an Aqueous Sol–Gel process is machined using an Abrasive Water Jet Machine (AWJM). The machinability of this composite is studied by varying the input parameters namely Jet Pressure (JP), Stand-Off Distance (SOD), and Traverse Speed (TS) on Surface finish. Garnet of 80 mesh size is used as an abrasive with a flow rate of 85?g/min. The microstructural characterization study reveals the presence of new element YPO4. This element enhances the machinability and reduced porosity in the composite. Microscopy examinations on the machined surface reveals that partial overlapping at low JP, poor surface finish at high JP and SOD, forged deficiency at maximum SOD and TS. The minimum levels of all input parameters are influenced to obtain acceptable Ra. Atomic Force Microscopy (AFM) on the kerf surface shows micro wear track and peaks. The Multiple Regression Analysis (MRA) is developed for Ra to check the adequacy. From the Analysis of Variance (ANOVA), SOD has a significant effect on Ra with a contribution of 53%. The influence of JP and TS on Ra is found to be 31% and 15%, respectively. 相似文献