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991.
为了辨识具有谐波减速器的柔性关节模型的关键参数,设计了一套基于多传感器融合的离线辨识方法,根据电机的位置传感器、电流传感器和关节力矩传感器的实验数据完成柔性关节模型关键参数的辨识.首先,建立采用谐波减速器柔轮输出的柔性关节模型;然后,使用正反转加载力矩的方法辨识出电机的力矩系数;并在空载的情况下,由关节力矩和电机输出力矩分别辨识出关节端和电机端的摩擦力;最后,采用敲击法初步辨识出关节的刚度和阻尼后,在关节位置受限条件下,逐渐增加电机输出力矩,得到柔性关节刚度和关节力矩的非线性关系.多次实验的结果显示,辨识出的参数具有较高的重复性,验证了该方法的有效性. 相似文献
992.
PVC新型改性剂AS的合成与应用 总被引:1,自引:0,他引:1
本文主要介绍PVC新型改性剂AS树脂的合成方法、产品性能及其在PVC异型材、管材、注射、压延片等加工领域中的应用。实验结果证明:该产品完全可以代替ACR加工助剂,并有很好的经济效益。 相似文献
993.
Seong-Soo Hong Gun-Dae Lee Jong-Won Park Dae-Won Park Kyung-Mok Cho Kwang-Jung Oh 《Korean Journal of Chemical Engineering》1997,14(6):491-497
In the present work, we have investigated the reduction of NO by propane over perovskite-type oxides prepared by malic acid
method. The catalysts were modified to enhance the activity by substitution of metal into A or B site of perovskite oxides.
In addition, the reaction conditions, such as temperature, O2 concentration, and space velocity have been varied to understand their effects on the catalytic performance. In the LaCoO3 type catalyst, the partial substitution of Ba and Sr into A site enhanced the catalytic activity in the reduction of NO.
For the La0.6Ba (Sr)o.4 Co1−x
FexO3 (x=0-1.0) catalyst, the partial substitution of Fe into B site enhanced the conversion of NO, but excess amount of Fe decreased
the conversion of NO. The surface area and catalytic activity of perovskite catalysts prepared by malic acid method showed
higher values than those of solid reaction method. The conversion of NO increased with increasing O2 concentration and contact time. The introduction of water into reactant feed decreased the catalytic activity but the deactivation
was shown to be reversible over La0.6Ba0.4Co1−x
,FexO3 catalyst. 相似文献
994.
995.
文明寨地区构造复杂,断块多,岩性变化大,一些地质问题不明,需要高精度三维资料处理来提高资料的纵、横向分辨率^[1][2]及为储层、油藏研究提供精确的依据。针对东濮文明寨地区高精度处理过程中的关键技术进行了大量分析试验,形成了一套适合东濮地区的较为完整的3D高精度地震资料处理流程。实际资料处理表明效果较好。 相似文献
996.
Ye Wan Wenhui Guo Jin Xiao Dazhou Yan Xiong Zhao Shuhu Guo Jianhua Liu Qifan Zhong Tao Yang Yu Zhao Xin Chang Xin Gao 《中国化学工程学报》2020,28(9):2248-2255
Ultra-high-purity silicon tetrachloride (SiCl4) is demanded as an electronic-grade chemical to meet the stringent requirements of the rapidly developing semiconductor industry. The high requirement for ultra-high-purity SiCl4 has created the need for a high-efficient process for reducing energy consumption as well as satisfying product quality. In this paper, a mass of production technology of ultra-high-purity SiCl4 was successfully developed through chlorination reaction in the ultraviolet (UV)-based photo microreactor coupled with the distillation process. The influences of key operational parameters, including temperature, pressure, UV wavelength and light intensity on the product quality, especially for hydrogen-containing impurities, were quantified by the infrared transmittance of Fourier transform infrared spectroscopy (FT-IR) at 2185 cm−1 and 2160 cm−1 indicating that characteristic vibrational modes of SiH bonds, as well as the operating conditions of distillation were also investigated as key factors for metal impurities removing. The advanced intensification of SiCl4 manufactured by the integration of photo microreactor and distillation achieves the products with superior specifications higher than the standard commercial products. 相似文献
997.
The flow pattern in a silo is important because it affects both the recovery of solids and the pressures on the silo wall during discharge. Wherever mass flow is not achieved, the boundary of the flow channel has significant implications for both the functional and structural design of the silo. Many techniques have been used for the study of flow patterns in model silos, but most cannot be used at full scale, and very few quality measurements at full scale have ever been made. This paper outlines a full scale experimental study in which the patterns of solids flow and the flow channel boundaries are reliably quantified.The full scale silo was specially designed, constructed and instrumented to exhibit funnel flow and to make observations of the solids flow pattern and the silo wall pressures. It had three outlets: one concentric, one fully eccentric and one in between. Three materials were used: iron ore pellets, slag fines and crushed basalt. This paper describes experiments involving iron ore pellets. The silo was seeded with radio frequency tags whose residence times were measured by detecting them on exit during discharge. The residence time data were studied to deduce the discharge flow pattern. This paper presents the results of three different flow pattern interpretation techniques: the best of them (mass-time relationships) is shown to give a very clear identification of the solids flow pattern and the flow channel boundary. 相似文献
998.
999.
Sang-Gon Kim Jong-Sung Park Jae-Sul An Kug Sun Hong Hyunho Shin Hyungsun Kim 《Journal of the American Ceramic Society》2006,89(3):902-907
Various types of crystalline ceramic fillers (TiO2 , ZrO2 , Al2 O3 , MgO, and cordierite) were added to BaO–ZnO–B2 O3 –SiO2 (BZBS) glass (5–20 wt%), and the resultant dielectric constant, coefficient of thermal expansion (CTE), and optical reflectance were investigated for the application of the composites to the barrier ribs in plasma display panels. All the investigated fillers were partially dissolved into the glass at the fabrication temperature (575°C), and the residual fillers were aligned along the boundaries of sintered glass frits. By considering all aspects of the properties, the addition of TiO2 fillers of about 10 wt% to BZBS glass was the most desirable of the types of fillers investigated. The addition of TiO2 filler (10 wt%) yielded 61% in optical reflectance, 8.3 × 10−6 K–1 in coefficient of thermal expansion, and 15.5 in dielectric constant, which were properties comparable with the currently used Pb-based barrier ribs. 相似文献
1000.
应用基于模糊数学与常规可靠性理论相结合的模糊可靠性设计方法,讨论钢制薄壁内压容器模糊静强度在不同工况时,有关标准可接受的模糊可靠度范围;对钢制薄壁内压容器静强度的模糊可靠度范围与安全系数的关系进行研究。分析认为容器静强度在满足最小模糊可靠度要求的前提下,可取屈服安全系数ns≥1.55与抗拉安全系数nb≥1.95。 相似文献