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用MAXScript脚本语言生成分形图形   总被引:3,自引:1,他引:2  
介绍了分形生成技术的原理与性质、MAXScript脚本语言的特点及功能,详细叙述了用MAXScript脚本语言生成分形图形的设计思想和实现方法。针对分形几何的特点,以具有严格自相似性的分形树为例,通过解释源代码、描述程序运行过程和结果,以及对生成的图片用3DSMAX进行再处理,分析了在3DSMAX环境中用MAXScript脚本语言生成分形图形这一新方法的优点和不足。  相似文献   
74.
Master sintering curve concepts as applied to the sintering of molybdenum   总被引:6,自引:0,他引:6  
Sintering experiments with various molybdenum powders are rationalized using a master sintering curve concept that collapses density, grain size, or other parameters onto a single curve. In this case, the integral work of sintering is developed and customized for different green densities. Construction of the master sintering curve is described to show how the curve can be normalized with respect to green density effects. Various grades of molybdenum for metal injection molding and die compaction are included in the analysis, processed over a range of heating cycles. Die-compacted samples of varying green densities are used to illustrate the efficacy of the new, normalized master sintering curve concept. Sintering cycle optimization is one possible outcome from this analysis.  相似文献   
75.
覆膜滤料的滤尘性能测试方法研究   总被引:1,自引:0,他引:1  
范柏祥  孙熙  王金波 《有色矿冶》2003,19(1):44-45,51
由于覆膜滤料的结构和性能有别于普通滤料,因而普通滤料的滤尘性能测试方法不完全适用于覆滤料。本文作者在总结实践经验的基础上,提出了在覆膜滤料的滤尘性能测试中应注意的一些问题和应增加的测试项目。  相似文献   
76.
胡进 《特钢技术》2007,13(4):22-25
针对W9Cr3M04V轧制成品材低倍碳化物剥落的形成原因分析,得出一次碳化物颗粒粗大、在1/4D至中心区域聚集是导致低倍热酸浸试验碳化物剥落的主因;由此进行冶炼过程中注速(锭形)、浇注温度选择对比工艺试验,得出在原有冶炼+轧制的工艺基础上选用2.2t锭、降低浇注温度(1489℃)能有效改善一次碳化物颗粒大小和聚集程度,进而有效降低低倍碳化物剥落倾向。  相似文献   
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Associations (dimer or aggregate) of anthracene (An) fluorophores tend to interrupt the monomer emission and reduce the quantum yield (ΦPL); therefore, poly(methyl methacrylate) (PMMA) chain was used in this study to chemically link to anthracene and to block the mutual associations among the anthracene fluorophores. With this aim, the target polymers were prepared by anionic polymerizations with 9,10‐dibromoanthracene/s‐butyllithium as initiating system to proceed polymerizations of methyl methacrylate (MMA) directly or in the presence of 1,1‐diphenylethylene (DPE). Use of DPE before addition of MMA produces stable initiating anionic species and avoids potential side reactions during polymerization; however, it also introduces four β‐phenylene rings around the central anthracene ring, which interfere with the corresponding emission pattern and reduce the ΦPL (32%) value due to potential interactions between phenylene rings and anthracene. On the contrast, polymerization without participation of DPE results in polymer with central anthracene ring directly connected to two PMMA chains, which gives clean vibronic emission pattern with limited association emissions and enhanced ΦPL (52%) value. Physical blending of anthracene by PMMA is less efficient to restrain the associations and results in a film of lower ΦPL (20%). © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   
79.
Smectite clays treated with quaternary ammonium salts have been utilized for decades in paints, greases, cosmetics, and personal care products as rheological modifiers. They have also been used in industrial wastewater treatment extensively. In more recent times these surface modified clays have demonstrated benefits in polymer/clay nanocomposites. The use of quaternary ammonium modifiers limits the usefulness of these composites in food packaging because they are not approved for direct food contact. It would be advantageous to have surface modifying chemicals acceptable for direct food contact in these composites. This article reports research conducted on a promising surface modifier pentaerythritol stearate (PS), which is approved by the FDA for inclusion in food as a preservative. The surface modification of montmorillonite with PS is reported in detail as well as the production of nanocomposites with selected polymers made with the modified clay. Molecular modeling and purification of commercial PS samples indicate that the mono‐ and diesters are the critical surface modifiers, although the as received commercial material works well in forming intercalated clay complexes. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   
80.
Polyarylene ether nitriles (PEN)/thermotropic liquid crystalline polymer (TLCP) blend was prepared via melt mixing. The immiscible phase morphologies, linear and nonlinear, as well as transient viscoelastic properties of the blend were studied using SEM, rheometer, and DMA. The linear dynamic viscoelastic behavior of the blend shows temperature dependence due to further evolution of the immiscible morphology and, as a result, the principle of time‐temperature superposition (TTS) is invalid. In the steady shear flow, the discrete TLCP phase is difficult to be broken up because of the high viscosity ratio of the blend systems, while is easy to be coarsened and followed by elongation, and finally, to form fibrous morphology at high TLCP content and high shear level. During this morphological evolution process, the transient stress response presents step increase and nonzero residual relaxation behavior, leading to increase of the dynamic viscoelastic responses after steady preshear. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   
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