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101.
Dehydroabietic acid (DHA), sodium stearate (NaSt), DHA/NaSt (1/1 wt/wt) mixture, the reaction products of DHA/NaSt (1/1 wt/wt) mixture after heating at 220°C for 10 min and sodium dehydroabietate (DHAA‐Na) were qualitatively analyzed by Fourier transform infrared spectrometry (FTIR) and wide angle X‐ray diffractometry (WAXD). The crystallization behavior, spherulitic morphology, optical and mechanical properties of iPP samples nucleated by DHA, NaSt, DHA/NaSt (1/1 wt/wt) mixture, and DHAA‐Na under the same concentration (0.3 wt %) were investigated by differential scanning calorimetry (DSC), polarized light microscope (PLM), optical and mechanical measurements. The results showed that an “in situ” reaction occurred between DHA and NaSt, and an effective transparent nucleating agent (DHAA‐Na) was produced during the melting blending of iPP and DHA/NaSt (1/1 wt/wt) mixture in the twin screw extruder. The crystallization onset and peak temperatures, the gloss and the mechanical properties were improved markedly; the crystallization half‐time, the spherulitic size, and the haze were reduced substantially when iPP samples are nucleated by DHA/NaSt (1/1 wt/wt) mixture. The optimum composition ratio of DHA/NaSt should be kept at ≈ 1/1 wt/wt and above 0.4 wt %/0.4 wt %. The DHA/NaSt bi‐component nucleator was effective for iPP with different MFR values. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
102.
翡翠透明度测量和分级 总被引:2,自引:0,他引:2
赵明开 《宝石和宝石学杂志》2000,2(3):4-7
透过率(T)是透过光强与入射光强的比值。不同物体的透明度只能在相同厚度下才能比较。建立了1mm厚的物体对光的透过率作为表征透明度的基本单位,称为单位透过率,用t表示。单位透过率和厚度为n的物体的透过率的转换公式为:t=n√T。只须测量物体厚度及该厚度的透过率通过计算就可以得到t值。在前人悲翠透明度定性分级的基础上,提出了悲翠透明度定量测量和分级的方法。 相似文献
103.
This paper reports a brief review of the key elements for WDM transport networks. In particular, the transmission aspects, the basic elements of WDM networking, and the issues relating to failure restoration and network management are taken into account. 相似文献
104.
Róbert Klement Katarína Drdlíková Daniel Drdlík Karel Maca 《Journal of the American Ceramic Society》2023,106(1):172-185
Transparent alumina doped with rare-earth or transition metal oxides represents a group of materials suitable for optical applications. Because of the birefringence of alumina, their preparation is demanding on the quality of starting materials, their advanced shaping, and pressure-assisted sintering. Spark plasma sintering and hot isostatic pressing have proven at achieving pore-free fine microstructures exhibiting high in-line transmission and a sufficient intensity of emitted light. The present review aims to summarize the results published on this topic, to compare them and on this base to propose other possible and/or appropriate approaches to future. 相似文献
105.
106.
孙艳玲 《山东轻工业学院学报》1996,10(1):21-24
本文就松木用酸性亚硫酸盐法蒸煮,生产描图纸浆进行了探讨性试验。对试验所得浆中戊糖含量偏低的原因从理论上进行了分析。同时,提出了提高戊糖含量的改进措施。 相似文献
107.
108.
Kharidah Muhammad Feri Kusnandar Dzulkifly Mat Hashim & Russly AbD. Rahman 《International Journal of Food Science & Technology》1999,34(3):275-280
Summary Characteristics of potato starch noodles substituted with native, phosphorylated and commercial phosphorylated (MTS283) tapioca starches were evaluated. Substitution of up to 17% with phosphorylated tapioca starch or up to 35% with MTS283 improved the quality of potato starch noodles. The resulting noodles were transparent and less brittle when uncooked, and were moderately elastic, less sticky and experienced lower cooking loss and less swelling when cooked. Substitution with native tapioca starch of up to 17% was also possible, but the uncooked noodles were less transparent and the cooked noodles swelled more and were less elastic. 相似文献
109.
110.
Soemmerring’s Rings Developed around IOLs,in Human Donor Eyes,Can Present Internal Transparent Areas
Justin Christopher DAntin Francesc Tresserra Rafael I. Barraquer Ralph Michael 《International journal of molecular sciences》2022,23(21)
Soemmerring’s rings consist of a ring of lens epithelial derived cells that grow along the periphery of an aphakic lens capsule, or around an intraocular lens. These rings when visualized frontally, appear opaque, however, in some cases the cells that compose these rings are organized in the same fashion as those in normal transparent adult lenses. Thus, our purpose was to test whether any part of the adult Soemmerring’s ring could be transparent and how this related to morphological factors. To study this, 16 Soemmerring’s rings were extracted from donor eye globes. After imaging, they were thickly sectioned sagittally in order to analyze the degrees of transparency of different areas. All samples were also histologically analyzed using alpha smooth muscle actin, Vimentin, wheat germ agglutinin and DAPI. Our results showed that many samples had some transparent areas, mostly towards the center of their cross-section. Of the factors that we analyzed, only lens fiber organization at the bow region and an increased area of mature lens fiber cells had a significant relation to the degree of transparency at the center. Thus, we can conclude that as Soemmerring’s rings mature, they can develop organized and transparent areas of lens cells. 相似文献