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71.
论述了新形势下推进装备管理问责制的重要意义,分析了推进装备管理问责制的基本要求,从强化意识、抓住重点、全面深化、信息主导及完善机制等5个方面提出了推进装备管理问责制需要重点把握的问题。 相似文献
72.
重型汽车发动机在用润滑油的更换合理与否,直接影响着发动机的使用寿命,而润滑油消耗的多少又与企业经济效益相关.针对我国重型汽车发动机更换在用润滑油过程中存在着不尽合理的现状,本文进行了讨论. 相似文献
73.
Zhou Zhou 《时间序列分析杂志》2013,34(4):508-516
The article considers simultaneous inference for a class of non‐stationary autoregressive models where the model parameters are allowed to vary smoothly over time. Simultaneous confidence tubes with asymptotically correct coverage probabilities are constructed to assess the overall patterns and magnitudes of the parameter functions over time. Simulation studies are conducted, and a real time‐series dataset is analyzed to demonstrate the usefulness of the proposed methodology. 相似文献
74.
A novel methodology for the order‐reduction of parabolic partial differential equation (PDE) systems with time‐varying domain is explored. In this method, a mapping functional is obtained, which relates the time‐evolution of the solution of a parabolic PDE with time‐varying domain to a fixed reference domain, while preserving space invariant properties of the initial solution ensemble. Subsequently, the Karhunen–Loève decomposition is applied to the solution ensemble on fixed spatial domain resulting in a set of optimal eigenfunctions. Further, the low dimensional set of empirical eigenfunctions is mapped on the original time‐varying domain by an appropriate mapping, resulting in the basis for the construction of the reduced‐order model of the parabolic PDE system with time‐varying domain. This methodology is used in three representative cases, one‐ and two‐dimensional (1‐D and 2‐D) models of nonlinear reaction‐diffusion systems with analytically defined domain evolutions, and the 2‐D model of the Czochralski crystal growth process with nontrivial geometry. © 2013 American Institute of Chemical Engineers AIChE J, 59: 4142–4150, 2013 相似文献
75.
Dr. RAMA SUBBA REDDY GORLA Professor 《Chemical Engineering Communications》2013,200(4-6):295-305
A model has been proposed for the momentum eddy diffusivity induced by free stream turbulence intensity. The eddy diffusivity model is applied to a sphere situated in a uniform crossflow in the presence of free stream turbulence. Numerical solution of the governing momentum and energy equations with the proposed eddy diffusivity model yielded results for the heat/mass transfer rates. The numerical predictions of the present work are compared with experimental data and the agreement between the two is seen to be very good. 相似文献
76.
舰艇蒸馏水舱内壁主要使用环氧聚酰胺类涂料作为防护涂料,防止舱壁腐蚀,防护期限一般为5年左右。这类涂料不仅防护期效短,而且在使用过程中涂膜易产生起泡、脱落等现象。本文中以硅氧烷包覆过的片状玻璃鳞片为主要防锈颜料,以低粘度环氧树脂为基料,制备了一种新型高固体份环氧玻璃鳞片涂料。实验表明,该涂料耐中性盐雾试验可达3000小时以上;常温条件下,在蒸馏水浸泡环境中,涂膜的有效防护期可达15年以上,并且经长期的蒸馏水浸泡,侵蚀,漆膜不会有可溶物质溶出,不会影响存储的蒸馏水水质,非常适合于长时间存储高纯度蒸馏水的水柜、水罐等设备的内壁防护需要,可有效满足舰艇、电厂等部门对蒸馏水存储设施的防腐要求。 相似文献
77.
Experimental study on the solvent regeneration of a CO2‐loaded MEA solution using single and hybrid solid acid catalysts 下载免费PDF全文
Zhiwu Liang Raphael Idem Paitoon Tontiwachwuthikul Fanghui Yu Helei Liu Wichitpan Rongwong 《American Institute of Chemical Engineers》2016,62(3):753-765
The performance of a hybrid solid acid catalyst consisting of a physical mixture of γ‐Al2O3 and H‐ZSM‐5 in terms of the rate and heat duty for solvent regeneration (i.e., CO2 stripping) of a CO2‐rich MEA solution was compared with the individual performance of γ‐Al2O3, H‐ZSM‐5, and H‐Y solid acid catalysts using MEA (2–7 mol/L), with initial CO2 loading of 0.5 mol CO2/mol MEA at 378 K. It was observed that any catalyst significantly decreased the energy required for CO2 regeneration. The performance of the catalysts investigated ranked as follows: γ‐Al2O3/H‐ZSM‐5 = 2/1 > γ‐Al2O3 > H‐ZSM‐5 > H‐Y if the process is in the lean CO2 loading region whereas it was H‐ZSM‐5 > γ‐Al2O3/H‐ZSM‐5 = 2/1 > γ‐Al2O3 > H‐Y if the process is in the rich CO2 loading region. These results highlight the joint dependence on Brønsted/Lewis acidity and mesopore surface area of heat duty for solvent regeneration. © 2015 American Institute of Chemical Engineers AIChE J, 62: 753–765, 2016 相似文献
78.
A novel operation of batch distillation-combination of varying colum pressure and total reflux-total efflux is studied experimentally. In the operation, the product is accumulated at the top of the column under total reflux and then drained off completely, and the column pressure is varying in the whole process. This process has been industrialized successfully with large profits. The conventional mode of batch distillation is improved by this method effectively: the separation eficiency and the yield of product are increased greatly, the operation time is shortened and the production cost is cut down. Moreover, the amount of condensation water is decreased and the over-high reboiler temperature is lowered. 相似文献
79.
在数字通信系统中为了克服码间干扰,常采用基于不需要使用训练序列的常数模算法的分数间隔盲均衡技术.但是该技术在对非常模信号,如高阶QAM信号,进行均衡时存在稳态均方误差大的缺陷.因此提出了一种基于常数模算法和自适应变模值符号Godard算法的联合盲均衡.新方法将常数模算法作为基础部分用来使接收信号的眼图睁开;将自适应变模值符号Godard算法作为第二部分用来进一步减少算法的残留误差.通过计算机仿真验证了新方法比基于常数模算法的分数间隔盲均衡具有更低的稳态均方误差. 相似文献
80.
推导出火管废热锅炉的面积富裕系数,系统生产负荷率、主线率3者之间的解析关系式,利用该公式可以确定废热锅炉副线设计的气量范围,认为现有的焚硫废热锅炉的面积富裕系数取值普遍偏大,提出1种测定火管废热锅炉实际面积富裕系数的具体计算方法。 相似文献