丝织品人工老化水解实验研究

模拟丝织品文物出土前在水中浸泡的状况,对植物染色的桑蚕丝绸进行水解老化实验,研究潮湿环境对丝织品文物老化所产生的影响,探讨染色丝绸的色彩在去离子水长期浸泡情况下的变化规律。研究涉及了6种丝绸样品:白色丝绸、红色丝绸、黄色丝绸、茶色丝绸、蓝色丝绸和黑色丝绸。通过对实验样品的色差分析,发现了各种颜色的丝绸样品在水解老化时的色泽变化规律,可以作为确定彩色丝织品文物保存环境的参考。     

浅谈冰荔枝酒的生产工艺

介绍了以广东省郁南县成熟荔枝为原料,将鲜荔枝破碎后,经酶解浸渍、果汁澄清、冷冻浓缩、低温发酵、陈酿、调配等工艺酿造出甘甜醇厚、酸甜协调、回味悠长,酒体丰满具有浓郁荔枝果香优质冰荔枝酒。最佳的工艺参数为：酵母加入量为1.5g/L,发酵温度13℃,酒度15%vol～16%vol,总糖260～280g/L,总酸4g/L。     

多因素共同作用下EPDM对PP稳定性的影响

通过对PP/EPDM共混物进行多因素条件下的老化,研究了EPDM对PP稳定性的影响。由样品老化前后的力学性能、表面形貌、玻璃化转变温度以及表面氧含量的变化分析表明:随着EPDM含量的增加,相应共混物的拉伸强度和断裂伸长率的变化趋势减缓;共混物的降解减弱,表面龟裂纹和脱落现象减轻。由此可见,EPDM能提高PP的抗老化能力。     

ACETYLATED PLANT-FIBER-REINFORCED POLYESTER COMPOSITES: A STUDY OF MECHANICAL,HYGROTHERMAL, AND AGING CHARACTERISTICS

The potential of acetylation of plant fibers to improve the properties of composites was studied. The chemical modification of oil palm empty fruit bunch (EFB), coconut fiber (Coir), oil palm frond (OPF), jute, and flax using noncatalyzed acetic anhydride were investigated. Proof of acetylation was indicated by the increase in weight percent gain (WPG). Acetylation at a reaction temperature of 120°C had resulted in the reduction in the tensile properties (stress, modulus, and elongation at break) of EFB and Coir composites. However, at 100°C, the acetylated samples exhibited improved properties. The mechanical properties of acetylated EFB- and Coir-fiber-reinforced polyester composites was evaluated at different fiber loadings. The tensile strength and modulus were improved, but elongation at break was slightly reduced upon acetylation, particularly at high fiber loading. Impact properties were moderately increased for those composites with fiber loadings up to 45%. Acetylation exhibited a low moisture absorption, comparable with glass-fiber composites. Acetylated EFB and Coir composites showed superior retention of tensile and impact properties after aging in water up to 12 months.     

低水泥浇注料中纯铝酸钙水泥和SiO_2微粉的“老化”试验

为了探讨纯铝酸钙水泥结合的低水泥浇注料"老化"的原因和影响因素,将SiO2微粉以及不同粒度、不同物相组成(CA相含量)、不同新鲜程度的纯铝酸钙水泥在温度为(20±1)℃、相对湿度>75%的潮湿环境中摊成厚度为2.5 cm左右的料层,放置一定时间(分别为0、3、7、14、28 d)使其老化,然后分别将它们与特级矾土(≤5、≤0.088 mm)、磷酸盐分散剂和减水剂等其他原料一起配制成浇注料,通过测定浇注料的可工作时间、初始流动性和早期(6 h)养护强度,来表征这些原料的老化速度.结果表明:(1)纯铝酸钙水泥的cA含量和细度越高,其老化速度越快.(2)"新鲜"的铝酸盐水泥比存放一段时间后的水泥的老化速度更快.(3)SiO2微粉的老化会导致浇注料的流动性变差,可工作时间变短.     

时效温度对非调质钢MFT8拉伸性能的影响

介绍了试验材料及方法,对冷拔非调质钢MFT8在不同温度下进行了时效处理,对试验结果进行了分析研究。分析结果表明,MFT8非调质钢具有较强的加工硬化能力,冷拔MFT8非调质钢经300℃时效后具有最佳的强度和塑性配合。     

Influence of aging behavior of Armos fiber after oxygen plasma treatment on its composite interfacial properties

This work concerns the aging behavior of Armos fiber and Armos fiber reinforced poly (phthalazinone ether sulfone ketone) (PPESK) composite after oxygen plasma treatment. Armos fiber surface chemical composition, surface morphology and roughness, and surface wettability as a function of storage time in air after oxygen plasma treatment were measured by X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM) and dynamic contact angle analysis (DCAA) system, respectively. The fiber surface aging behavior could be detected obviously in chemical composition and surface wettability, whereas the surface morphology and roughness remained nearly stable after storing in air as long as 10 days after oxygen plasma treatment. The effects of surface aging behavior after oxygen plasma treatment on Armos fiber reinforced PPESK composite interfacial properties were evaluated by interlaminar shear strength (ILSS) test and humid resistance measurement. It was found that the values of ILSS reduced and the composite humid resistance properties decayed. The polar functional groups that were reoriented from the surface into the bulk of the fibers or moved away from the fiber surfaces, maybe responsible for the weak interfacial strength between the fiber and the matrix in composite system.     

稀土Er元素对6063合金时效处理的影响

用硬度测试,金相分析,透射电镜分析等方法研究Er元素对轧制后6063合金时效过程中β″相析出的影响,结果表明Er元素的加入对固溶后的合金再结晶晶粒长大有非常明显的抑制作用,适量的Er元素有助于合金力学性能的改善,与合金生成的Al3Er相对合金β″相的析出有促进作用,加快了β″相的析出。     

Reliability of multilayer ceramic capacitors with nickel electrodes

The reliability of multilayer ceramic capacitors (MLCCs) with Ni internal electrodes has been studied trom the viewpoint of partial oxygen pressure (P_O2) during firing. It is shown that the load-life time of the insulation resistance (1R) was prolonged by firing under low Po₂ annealing after firing, and the addition of dopants. It is also shown that the generation of oxygen vacancies led to the degradation of IR. Annealing treatment for the oxidation of the dielectric body accelerates the dielectric aging of MLCCs. It is found that the appropriate control of the P_O2 during firing can improve the reliability of MLCCs with Ni electrodes to a level as high as that of MLCCs with precious metal electrodes. Thus, we have developed an MLCC with Ni electrodes that features high reliability and a large capacitance of 10 μF for the Y5V characteristic and 4.7 μF for the X7R characteristic, both in the case of the C3216 (3.2 mm × 1.6 mm × 1.4 mm) form.     

板栗制品老化检测方法的研究

本文研究了检测板栗制品老化的几种方法.结果表明:硬度法,离心水质量法,碘吸光度法和酶水解法为检测板栗制品老化的代表方法.其中,硬度法比较简单,但不适合于精确测量;离心水法适合检测与直链淀粉有关的老化;碘吸光度法可以间接地反映淀粉的老化;酶水解法可用于检测淀粉的老化,但是过程比较繁琐.