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1.
选用实验室制备的四种新型反应型受阻胺类光稳定剂(r-HALS):4-甲基丙烯酰氧基-2,2,6,6-四甲基哌啶醇酯(MTMP)、4-丙烯酰氧基-2,2,6,6-四甲基哌啶醇酯(ATMP)、4-甲基丙烯酰氧基-1,2,2,6,6-五甲基哌啶醇酯(MPMP)和4-丙烯酰氧基-1,2,2,6,6-五甲基哌啶醇酯(APMP),实现了紫外光固化聚合物涂层(膜)的原位(in situ)光稳定化。通过室内人工光老化实验和在光氧化过程中黄度指数(Yellowness Index,YI)的监测,再与典型的商用HALS(Tinuvin770和Tinuvin292)进行平行实验对比,考察了r-HALS对紫外光固化聚合物涂层的光防护效果,探索一条紫外光固化聚合物涂层原位(in situ)光稳定化的新途径。  相似文献   
2.
The aim of this study was to investigate whether total carotenoid content (TCC) in noble scallop Chlamys nobilis is related to body tissue, shell colour, and gender. TCC was determined by a UV–vis recording spectrophotometer in tissue of gonad, adductor, mantle, and gill separately sampled from male and female individuals with orange and brown shell colours from the same cultured population. TCC was significantly different among body tissues, depending on shell colour and gender, ranging from 0.73 to 59.85 μg g−1. In general, TCC was greater in the order of gonad > mantle > adductor > gill. In the same gender, orange shell colour individuals contained significantly higher TCC than brown ones in all four tissues (P < 0.05). In the same shell colour, female contained significantly higher TCC than male in gonad and adductor tissues (P < 0.05).  相似文献   
3.
王旭  陈少克 《轻工机械》2010,28(6):10-13
利用机构学的方法对双曲肘合模机构进行了运动分析,并确立了合模行程、各肘杆尺寸及最大启模角等参数间的关联关系。通过使用Pro/E二次开发技术,讨论了应用Pro/toolkit进行菜单开发及零件参数化实现的方法;以MFC对话框设计技术和VC++建立了双曲肘合模机构参数驱动自动生成技术,开发出了与Pro/E 4.0系统集成的合模机构零件参数化设计系统。  相似文献   
4.
The production of metabolites by microalgae is affected by environmental conditions in which they are living. The metabolic responses of two marine microalgae, Nitzschia closterium and Isochrysis zhangjiangensis, to a 3-day UVA-stress and 3-day UVA-recovery treatment were compared, based on their growth, fatty acid profiles and content of total carotenoids. When cultured under photosynthetically active radiation, coupled with UVA treatment, both microalgae underwent a significant increase in their growth during the UVA-recovery period compared to the control. The proportions of polyunsaturated fatty acids, including linoleic acid and eicosapentaenoic acid, as well as total carotenoids, were significantly increased in both microalgae, mainly in the UVA-stress period, but not the UVA-recovery period. The metabolic responses of the two microalgae to UVA treatment were species-dependent and could be utilised to produce microalgal biomass rich in polyunsaturated fatty acids and carotenoids for use as functional food ingredients.  相似文献   
5.
酶法制取龙头鱼水解蛋白及海鲜风味料的研究   总被引:11,自引:0,他引:11  
研究了酶法水解龙头鱼的工艺及其水解液脱苦的适宜条件。通过正交试验确定了以水解龙头鱼蛋白为基料制备复合调味料的较优配方 ,获得口感丰富、具有浓郁海鲜风味的产品。  相似文献   
6.
    
The subject of this work is to investigate the effect of fly ash on the strength of concrete filled steel tubular columns from 28 to 365 days. A contrast study was carried out on concrete filled steel tubular columns incorporating 10–40 wt% fly ash, and for control Portland cement concrete filled steel tubular columns. The effect of pre-coating the inner surface of steel tubes with a thin layer of fly ash was also studied. Assessments of the concrete mixes were based on the compressive strength and the bond strength. The results show that a lower replacement with fly ash can improve both bond strength and compressive strength, while a higher replacement with fly ash requires a relatively longer time to achieve similar beneficial effects. Pre-coating the inner surface of steel tubes with a thin layer of fly ash can notably improve the bond strength. The microstructure of the interface between concrete and steel tube was also studied by using scanning electron microscopy analyzer.  相似文献   
7.
    
A tracking detector composed of aluminized mylar drift tubes is under development for the Fermilab experiment 760. A prototype chamber has been constructed. Results on the longitudinal coordinate determined by charge division are given. Spatial resolution values below 2 mm (rms) were found, corresponding to <1% of the chamber length. Results on chamber ageing are also discussed.  相似文献   
8.
    
《Thin》1988,6(2):81-108
The Rayleigh-Ritz method is extended to thin-walled structures on continuous supports by means of the combinations of frame modes transversely and continuous beam modes longitudinally. Effects of warping, distortion and shear-lag are considered simultaneously. The thin-walled structure problem is reduced to simpler plane frame and continuous beam problems. Numerical results are compared to the finite element and finite strip methods. The present method is advantageous over both the finite element and finite strip methods in the reduced number of generalised coordinates and its ability to use the existing frame programmes to analyse thin-walled structures. No new elements are required to be generated.  相似文献   
9.
以乙交酯和淀粉为原料,三乙胺为催化剂,在二甲基亚砜介质中合成了聚羟基乙酸接枝淀粉共聚物。讨论了原料配比和反应时间对共聚物接枝率(G)、接枝效率(E)和单体转化率(C)的影响。采用核磁共振谱仪(1H-NM R)、傅立叶变换红外光谱仪(FT-IR)、X射线粉末(多晶)衍射仪(XRD)、差式扫描量热仪(DSC)以及体外降解试验,研究了接枝共聚物的结构和性能。实验结果表明,将乙交酯单体和淀粉接枝共聚,可以得到一类新的可降解聚合物。  相似文献   
10.
    
A mathematical model is presented to obtain the effective thermal conductivity and the effective heat capacity in composite materials due to oscillating temperature field. An integro-differential equation for temperature field in composites is derived using the Green's function for heat conduction. The ensemble averaged temperature field is determined by a self-consistent scheme to yield algebraic equations for the effective thermal conductivity and the effective heat capacity. The obtained expression for the effective thermal conductivity is not symmetrical with the interchange of the matrix phase and the inclusion phase.  相似文献   
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