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791.
在云南云天化石化有限公司15万t/a的聚丙烯(PP)装置上,采用美国Grace公司开发的UnipolR无规共聚PP工艺及其C 702催化剂,开发生产出合格的食品注塑级奶茶杯PP专用料RM 060 T。结果表明:开发出合格RM 060 T的优化工艺条件为:催化体系的Al/Si,Al/Ti摩尔比分别为4.5~5.5,65~85,乙烯/丙烯的摩尔比为0.022~0.026,氢气加入量为6~8 kg/h,反应器的冷凝量为4%~9%;聚合条件为:反应温度60.0~64.0℃,反应压力3.00~3.20 MPa,循环气流速0.38~0.40 m/s,流化床床层料位高度18.5~20.0 m;其产品的熔体流动速率为5.5~6.5 g/min、弯曲模量不小于800 MPa、简支梁缺口冲击强度不小于3.7 kJ/m2、雾度不大于10%、正己烷溶出物质量分数为0.7%,二甲苯可溶物质量分数为10.2%。 相似文献
792.
793.
为了构建具有保面积参数化的双二次Bézier曲面,提出2种双二次Bézier曲面的构造算法.首先根据曲面第一微分基本形式,推导双线性和双二次Bézier曲面满足保面积参数化的约束条件,得出具有保面积参数化的双线性有理Bézier曲面只能是平行四边形的结论;然后根据双二次曲面的约束条件,通过求解方程组的形式设计符合约束条... 相似文献
794.
795.
Yahui WANG 《等离子体科学和技术》2022,24(2):25105
The parametric decay process of a reversed shear Alfvén eigenmeode (RSAE) into a geodesic acoustic mode and a kinetic RSAE is investigated using nonlinear gyrokinetic theory. The excitation conditions mainly require the pump RSAE amplitude to exceed a certain threshold, which could be readily satisfied in burning plasmas operated in steady-state advanced scenario. This decay process can contribute to thermal plasma heating and confinement improvement. 相似文献
796.
797.
Due to the growing interest in studying the compression and disruption of the plasma filament in magnetic fusion devices and Z-pinches, this work may be important for new developments in the field of controlled thermonuclear fusion. Recently, on a coaxial plasma accelerator, we managed to obtain the relatively long-lived (∼300 μs) plasma filaments with its self-magnetic field. This was achieved after modification of the experimental setup by using high-capacitive and low-inductive energy storage capacitor banks, as well as electrical cables with low reactive impedance. Furthermore, we were able to avoid the reverse reflection of the plasma flux from the end of the plasma accelerator by installing a special plasma-absorbing target. Thus, these constructive changes of the experimental setup allowed us to investigate the physical properties of the plasma filament by using the comprehensive diagnostics including Rogowski coil, magnetic probes, and Faraday cup. As a result, such important plasma parameters as density of ions and temperature of electrons in plasma flux, time dependent plasma filament's azimuthal magnetic field were measured in discharge gap and at a distance of 23.5 cm from the tip of the cathode. In addition, the current oscillograms and I–V characteristics of the plasma accelerator were obtained. In the experiments, we also observed the charge separation during the acceleration of plasma flow via oscillograms of electron and ion beam currents. 相似文献
798.
799.
Heejin Lee Sadegh Papari Giulio Bernardini Riccardo Gallorini Luca Rosi Franco Berruti 《加拿大化工杂志》2023,101(3):1271-1285
The objectives of this study were to examine how to recycle cup waste efficiently and effectively and to determine if cup waste can be converted into liquid, solid, and gas value-added products by slow pyrolysis. The characteristics and potential utilizations of the pyrolysis products were investigated. The study included the effects of temperature, heating rate, and different feedstocks. The yield of pyrolysis oil derived from cup waste increased from 42% at 400°C to 47% at 600°C, while the yield of char decreased from 26% at 400°C to approximately 20% at 600°C. Acetic acid and levoglucosan were identified as the main components of the pyrolysis oil. The char obtained at 500°C was physically activated at 900°C for 3 h with CO2. The adsorption capacity of the activated char was investigated with model compounds, such as methyl orange, methylene blue, ibuprofen, and acetaminophen. The results showed that the adsorption capacity of the activated char was similar to that of commercial activated carbon produced from peat. The higher heating value of the produced gas stream calculated at 400°C was 19.59 MJ/Nm3. Also, conventional slow pyrolysis (CSP) and microwave-assisted pyrolysis (MAP) technologies were compared to determine the differences in terms of products yields, composition and characteristics of the pyrolysis oil, and their potential applications. The CSP yields higher liquid products than MAP. Also, the pyrolysis oil obtained from the CSP had significantly more levoglucosan and acetic acid compared to that of the MAP. 相似文献