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101.
本文简要阐述了北化院BCS01和上海院SLC-S两种国产气相聚乙烯浆液催化剂的性能、催化剂结构,在Unipol聚乙烯工业装置上应用结果,以及和进口同类催化剂UCAT-J的性能比较。 相似文献
102.
Tiina Komulainen Mauri Sourander Sirkka-Liisa Jms-Jounela 《Computers & Chemical Engineering》2004,28(12):2611-2619
103.
葛丰化工厂磷酸萃取槽反应热不能有效移出,限制了生产能力的提高,通过采用低位真空冷却装置移走反应热,并同时改造水循环系统。改造后,投矿浆量达16t/h〔矿浆w(H2O)35%〕,生产能力从技改前2.67tP2O5/h提高到4.56tP2O5/h,萃取温度稳定控制在83~85℃。由于结晶状况改善,萃取率、洗涤率分别提高达96.33%、99.04%,能耗从181.3kW·h/tP2O5降低到149.8kW·h/tP2O5,含氟废气排放量从30000m3/h减少到小于6000m3/h。 相似文献
104.
Koki Murano Tomoyoshi Shimobaba Atsushi Sugiyama Naoki Takada Takashi Kakue Minoru Oikawa Tomoyoshi Ito 《Computer Physics Communications》2014
We report fast computation of computer-generated holograms (CGHs) using Xeon Phi coprocessors, which have massively x86-based processors on one chip, recently released by Intel. CGHs can generate arbitrary light wavefronts, and therefore, are promising technology for many applications: for example, three-dimensional displays, diffractive optical elements, and the generation of arbitrary beams. CGHs incur enormous computational cost. In this paper, we describe the implementations of several CGH generating algorithms on the Xeon Phi, and the comparisons in terms of the performance and the ease of programming between the Xeon Phi, a CPU and graphics processing unit (GPU). 相似文献
105.
全国48家化肥催化剂制造厂总能力为57Kt/a,产量近30kt/a,设备利用率不到50%。平均万吨氨耗催化剂10.36t,高于国外5.60t水平。现生产31个品种203个型号的催化剂中有103种经部级鉴定,但经常使用的约50种。目前化肥催化剂工业水平与国外相比还存在四方面差距。 相似文献
106.
An open-source multi-DOF articulated robotic educational platform for autonomous object manipulation
This research presents an autonomous robotic framework for academic, vocational and training purpose. The platform is centred on a 6 Degree Of Freedom (DOF) serial robotic arm. The kinematic and dynamic models of the robot have been derived to facilitate controller design. An on-board camera to scan the arm workspace permits autonomous applications development. The sensory system consists of position feedback from each joint of the robot and a force sensor mounted at the arm gripper. External devices can be interfaced with the platform through digital and analog I/O ports of the robot controller. To enhance the learning outcome for beginners, higher level commands have been provided. Advanced users can tailor the platform by exploiting the open-source custom-developed hardware and software architectures. The efficacy of the proposed platform has been demonstrated by implementing two experiments; autonomous sorting of objects and controller design. The proposed platform finds its potential to teach technical courses (like Robotics, Control, Electronics, Image-processing and Computer vision) and to implement and validate advanced algorithms for object manipulation and grasping, trajectory generation, path planning, etc. It can also be employed in an industrial environment to test various strategies prior to their execution on actual manipulators. 相似文献
107.
李方伟 《化学工业与工程技术》2003,24(2):47-48
简述了三聚氰胺生产流程、冷气风机的作用和结构,介绍了冷气风机密封泄漏的计算机单元模拟过程,提出了以风机进出口温差作为判断其密封泄漏量大小的依据。 相似文献
108.
Miguel Martínez-Espronceda Jesús D. Trigo Santiago Led H. Gilberto Barrón-González Javier Redondo Alfonso Baquero Luis Serrano 《Computer methods and programs in biomedicine》2014
Experiences applying standards in personal health devices (PHDs) show an inherent trade-off between interoperability and costs (in terms of processing load and development time). Therefore, reducing hardware and software costs as well as time-to-market is crucial for standards adoption. The ISO/IEEE11073 PHD family of standards (also referred to as X73PHD) provides interoperable communication between PHDs and aggregators. Nevertheless, the responsibility of achieving inexpensive implementations of X73PHD in limited resource microcontrollers falls directly on the developer. Hence, the authors previously presented a methodology based on patterns to implement X73-compliant PHDs into devices with low-voltage low-power constraints. That version was based on multitasking, which required additional features and resources. This paper therefore presents an event-driven evolution of the patterns-based methodology for cost-effective development of standardized PHDs. The results of comparing between the two versions showed that the mean values of decrease in memory consumption and cycles of latency are 11.59% and 45.95%, respectively. In addition, several enhancements in terms of cost-effectiveness and development time can be derived from the new version of the methodology. Therefore, the new approach could help in producing cost-effective X73-compliant PHDs, which in turn could foster the adoption of standards. 相似文献
109.
Recent studies of self-condensation and co-condensation of melamine-formaldehyde resins; cure at low temperatures 总被引:1,自引:0,他引:1
Self-condensation: recent research on the chemical pathways by which alcoholated melamine-formaldehyde (MF) resins react with themselves and on the product structures is summarized. Model compound studies suggest that
bridges are less stable than widely thought unless they are in hexahydro-1,3,5-triazine ring structures. In acyclic structures they are probably less stable than
bridges. Co-condensation: studies of how the composition of MF resins influences the rates of reaction with poly(ol) co-reactant show that MF resins that contain very low levels of
and/or
functionality are quite reactive. Reactivities of a variety of poly(ester) and acrylic coreactants were studied. By combining reactive MF resins with reactive co-reactants one can formulate high solids enamels that cure by co-condensation in 30 min at 50 to 65 °C with 0.5 parts per hundred (phr) of p-toluenesulfonic acid (p-TSA) catalyst. Cure at 25 °C appears feasible with higher catalyst levels. 相似文献
110.
The gasoline and distillate sulfur regulations promulgated throughout the world to reduce tail-pipe emissions are now strongly impacting refinery operations and investments. FCC gasoline is recognized as the principal contributor of sulfur to the gasoline pool and has become the focus for meeting the new specifications. The difficulty in removing sterically hindered sulfur species in the fluid catalytic cracking unit (FCCU) cycle oil drives up the hydrogen and investment costs for treating the distillates. Although installation of pre- and post-treatment facilities is planned by many refiners, other non-capital approaches such as undercutting are being evaluated to meet interim and future sulfur levels. Even when expensive treatment facilities are installed, operating costs can be lowered and the flexibility of the facility increased with improvements in the ability to remove sulfur in the FCCU. In this article, we detail Petro-Canada's experience in integrating Albemarle's RESOLVE sulfur reduction technology with a combination of innovative process ideas. These concepts include heavy naphtha recycle, coprocessing of hydrogen donor feeds, and recycle of light cycle oil (LCO) to a specially designed stripper reactor. Special attention is paid to the interaction of deep FCC feed hydrodesulfurization with the FCC performance. The results demonstrate that very low FCC gasoline sulfur levels can be achieved without significant capital investment through novel approaches to recycle, creative integration of cat feed hydrotreating unit (CFHTU)-FCCU designs and operations, and application of state-of-the-art sulfur reduction additive technology. An added benefit of the RESOLVE 950 sulfur reduction technology is the substantial elimination of sulfur oxides in the FCC flue gas. This has been observed in Petro-Canada operations and numerous other RESOLVE 950 applications around the world. 相似文献