CFM56-3发动机转子咬合的原因分析及处理措施

本文就CFM56-3型发动机罕见的转子咬合现象对其成因进行了深入的分析,结合笔者工作实践提出了如何避免或降低咬合风险,并对出现咬合现象后提出了的较为有效的处理措施,为业内对该型发动机的航线维护提供了有益的借鉴。     

油井管特殊扣产品拧接的自动判定法

在油井管特殊扣产品的加工过程中,拧接是一个重要工序,而拧接设备是否具有自动判定的功能,自动判定方法合适与否,都会对生产节奏和质量控制产生影响。本文介绍了一种自动判定的方法,通过对拐点的扭矩数值、圈数的判断,再加上一些防错手段,实现对特殊扣拧接曲线的自动判定。     

首钢长钢公司ER50—6焊丝用热轧盘条生产实践

简要介绍长钢轧钢厂ER50—6热轧盘条的试生产情况。通过采取控制化学成分、开轧温度、吐丝温度及风冷相变等措施。不断完善生产工艺，使盘条的各项性能达到了标准要求，从而满足了用户要求。     

臭氧在2-硝基-4-甲砜基苯甲酸合成中的作用

研究了臭氧在2-硝基4-甲砜基甲苯的氧化过程中的作用。以2-硝基-4-甲砜基甲苯为原料氧化制备2-硝基4-甲砜基苯甲酸的过程，分别使用硝酸、五氧化二钒和臭氧等多种氧化剂．通过比较这三种氧化剂单独使用和混合使用的效果，分析臭氧在该有机物的氧化中所起的作用．为臭氧合理使用提供依据。     

丙二醇和碳酸二甲酯联产连续生产新工艺

本工艺成功解决了传统生产工艺中催化剂与丙二醇难以分离,导致丙二醇产率低、纯度低、不能连续生产的问题。生产的丙二醇的质量更好,节能、产率高,废物实现零排放,实现了连续生产。     

Nonlinear PI control for variable pitch wind turbine

Wind turbine uses a pitch angle controller to reduce the power captured above the rated wind speed and release the mechanical stress of the drive train. This paper investigates a nonlinear PI (N-PI) based pitch angle controller, by designing an extended-order state and perturbation observer to estimate and compensate unknown time-varying nonlinearities and disturbances. The proposed N-PI does not require the accurate model and uses only one set of PI parameters to provide a global optimal performance under wind speed changes. Simulation verification is based on a simplified two-mass wind turbine model and a detailed aero-elastic wind turbine simulator (FAST), respectively. Simulation results show that the N-PI controller can provide better dynamic performances of power regulation, load stress reduction and actuator usage, comparing with the conventional PI and gain-scheduled PI controller, and better robustness against of model uncertainties than feedback linearization control.     

基于富氧燃烧CCS技术对我国低碳发展的研究

本文介绍了低碳发展的理念和实现路径,分析了CCS技术为低碳发展提供了切实可行的技术基础;介绍了燃烧前捕集、富氧燃烧捕集和燃烧后捕集技术,认为富氧燃烧捕集技术综合效益较高,对于发展低碳经济而言或许是一项技术创新的解决方案。     

Theoretical study of the zero-gap organic conductor α-(BEDT-TTF)2I3

Abstract

The quasi-two-dimensional molecular conductor α-(BEDT-TTF)₂I₃ exhibits anomalous transport phenomena where the temperature dependence of resistivity is weak but the ratio of the Hall coefficient at 10 K to that at room temperature is of the order of 10⁴. These puzzling phenomena were solved by predicting massless Dirac fermions, whose motions are described using the tilted Weyl equation with anisotropic velocity. α-(BEDT-TTF)₂I₃ is a unique material among several materials with Dirac fermions, i.e. graphene, bismuth, and quantum wells such as HgTe, from the view-points of both the structure and electronic states described as follows. α-(BEDT-TTF)₂I₃ has the layered structure with highly two-dimensional massless Dirac fermions. The anisotropic velocity and incommensurate momenta of the contact points, ±k₀, originate from the inequivalency of the BEDT-TTF sites in the unit cell, where ±k₀ moves in the first Brillouin zone with increasing pressure. The massless Dirac fermions exist in the presence of the charge disproportionation and are robust against the increase in pressure. The electron densities on those inequivalent BEDT-TTF sites exhibit anomalous momentum distributions, reflecting the angular dependences of the wave functions around the contact points. Those unique electronic properties affect the spatial oscillations of the electron densities in the vicinity of an impurity. A marked behavior of the Hall coefficient, where the sign of the Hall coefficient reverses sharply but continuously at low temperatures around 5 K, is investigated by treating the interband effects of the magnetic field exactly. It is shown that such behavior is possible by assuming the existence of the extremely small amount of electron doping. The enhancement of the orbital diamagnetism is also expected. The results of the present research shed light on a new aspect of Dirac fermion physics, i.e. the emergence of unique electronic properties owing to the structure of the material.     

In situ observation of recovery of lath structure in 9% chromium creep resistant steel

Abstract

The recovery process of the lath structure during tempering was investigated by in situ observations of 9% chromium creep resistant steel using TEM. A decrease of dislocation density inside the lath grains and an increase in lath width takes place during tempering. In situ observations revealed lath boundary migration and the disappearance of laths during tempering. Lath boundary migration is caused by repeat bulging and migration of local parts of the lath boundaries. Relatively small laths tend to disappear, leading to a decrease in the total energy of lath boundaries. All laths do not start to disappear at the same time; the rate of lath boundary migration differs with boundaries. The driving force of these microstructural changes is the strain accumulated by the martensitic transformation. Moreover, the recovery of the lath structure does not occur homogeneously during tempering because the strain does not distribute homogeneously in the lath structure.     

基于Q学习的企业信息化冲突研究

信息化作为当前企业提升竞争能力的重要手段，在实施的过程中会面临多种技术和管理上的冲突。而对这些冲突缺乏足够的认识和有效的解决机制，会直接影响到信息化项目的成败。为此从信息化冲突产生的原因入手，建立信息化冲突的模型，剖析问题的实质，并构建了基于Q学习的冲突解决机制，为企业信息化过程中的冲突化解提供一定的指导。