EA4T钢纯净化冶炼工艺研究

本文通过对车轴钢EA4T的冶炼和浇注工艺进行研究,提高EA4T钢的纯净度,降低EA4T钢的超声波探伤和磁粉探伤报废率,保证车轴钢产品质量的稳定性,从而达到提高车轴钢EA4T的成材率,实现EA4T的国产化生产的目的。     

痂囊腔菌素A的光敏活性探讨

用人工发酵生物合成的方法制备得到痂囊腔菌素A简称EA。通过电子顺磁共振技术(EPR)对EA氮氧自由基的光敏化学反应,研究光生物活性的抑菌试验,EA光动力学对人Hce-8693盲肠癌细胞增殖周期、诱导凋亡的探讨及量子化学的计算,阐明了痂囊腔菌素的光敏活性。     

The neuroprotection of electro-acupuncture via the PGC-1α/TFAM pathway in transient focal cerebral ischemia rats

ATP depletion is one of the pathological bases in cerebral ischemia. Electro-acupuncture (EA) is widely used in clinical practice for ischemia. However, the mechanism of EA remains unclear. The purpose of this study was to investigate whether EA could activate the AMPK/PGC-1α/TFAM signaling pathway and, consequently, increase the preservation of ATP in rats with ischemia. In this study, 48 rats were randomly divided into four groups as a sham-operation control group (sham group), a middle cerebral artery occlusion group (MCAO group), an EA group, and an EA group blocked by the AMPK inhibitor compound C (EA + CC group) (N = 12/group). The rats of the EA group and EA + CC group received the EA treatment for 7 days. The rats that belonged in the two remaining groups were only grasped in the same condition. Then, their brain tissues were collected for further detection. When compared with other groups, EA significantly reduced neurological deficits score and increased motor function. The cerebral infarction volume was significantly reduced in the EA group according to TTC staining. With western blot, we found that EA improved the ratio of p-AMPKα/AMPKα (P < 0.05), however, there is no difference between the MCAO group and sham group (P > 0.05). In addition, EA also increased the expression of PGC-1α and TFAM (all P < 0.05). By Elisa, we observed that EA increased the preservation of ATP (P < 0.05) and mitochondrial respiratory enzymes, including Complex I (P < 0.05), Complex IV (P < 0.05), but not Complex III (P > 0.05). In summary, we conclude that EA may protect against ischemic damage in MCAO rats, improve the preservation of ATP and mitochondrial respiratory enzymes. This effect may be positively regulated by the activation of the PGC-1α/TFAM signaling pathway.     

Effects of electroacupuncture on a degenerated intervertebral disc using an in-vivo rat-tail model

Electroacupuncture (EA) has long been used as conservative treatment for low back pain (LBP). Its effect on relief of back pain has been demonstrated in many clinical studies. However, whether it has any effect on the biological properties of an intervertebral disc, which is one of the major causes of LBP, is still unclear. The aim of this study was, therefore, to investigate the effects of EA with different simulation frequencies on an intervertebral disc with simulated degeneration using an in-vivo rat-tail model. In this study, 33 rats were used. Disc degeneration was simulated in the rat caudal 8-9 disc via continuous static compressive loading of 11 N for 2 weeks. EA with a frequency of 2 or 100 Hz was then applied to the degenerated disc for 3 weeks with 3 sessions/week and 20 min/session. The intervertebral disc height was measured before and after compression as well as after EA intervention for 3 weeks. The static compression was found to result in a reduction in the disc height of about 22 per cent. There was no evidence that this change could be reversed after resting or the EA intervention. However, EA at 100 Hz was found to induce a further decrease in disc height, which was not shown for the rats after resting or EA at 2 Hz. The results of this study showed that effects of EA on disc degeneration are frequency dependent and adverse effects could result if EA at a certain frequency was used.     

Work-in-process scheduling by evolutionary tuned fuzzy controllers

In this paper, an evolutionary algorithm (EA) strategy for the optimization of generic work-in-process (WIP) scheduling fuzzy controllers is presented. The EA strategy is used to tune a set of fuzzy control modules that are used for distributed and supervisory WIP scheduling. The distributed controllers objective is to control the rate in each production stage in a way that satisfies the demand for final products while reducing WIP within the production system. The EA identifies those sets of parameters for which the fuzzy controller performs optimal with respect to WIP and backlog minimization. The proposed EA strategy is compared with known heuristically tuned distributed and supervised fuzzy control approaches. Extensive simulation results show that the EA strategy significantly improves the system’s performance.     

国产高速重载列车车轴用钢EA4T的冷脆转变温度测定

EA4T钢是世界先进标准EN13261规定的高速、重载铁路车轴用钢,极端气候状况的频发对列车安全运行提出了严峻考验。本文对国产EA4T钢进行低温系列冲击试验,对其冷脆转变温度进行了测量分析。试验表明:EA4T钢经680℃回火空冷后的冷脆转变温度为-108℃。     

再沸器改造粘接工艺的开发

1　前言北京燕山石油化工股份有限公司化工一厂裂解装置经过技术改造后乙烯产量由年产 30万吨上升为年产 45万吨。但裂解装置冷区预脱甲烷塔再沸器ＥＡ319、ＥＡ35 0 (如图 1(ａ)所示 )在使用过程中 ,物料沿换热管管壁回流 ,严重影响了产品的回收率和产品质量。经分析认为是由于再沸器出口距离管板有高度差造成的。为了解决该生产过程中的工艺问题 ,拟对ＥＡ319、ＥＡ35 0再沸器进行改造 ,将再沸器上端的换热管接长 ,使其高度达到出口位置 ,物料从换热管流出后直接从出口流走 ,避免物料回流 ,如图 1(ｂ)所示。图 1　ＥＡ315、ＥＡ350再沸器…     

Component-based modeling of enterprise architectures for collaborative manufacturing

Agility and collaboration are key factors in collaborative manufacturing. An enterprise architecture (EA) framework for collaborative manufacturing has to support agility and have the ability to increase opportunities for collaboration. In this paper, an architecture-unit-based enterprise architecture (AUEA) framework is introduced for collaborative manufacturing. It supports the agility and collaboration ability of the EA using architecture units (AUs) and semantics of the metamodel. Each AU is a business-driven minimum EA component which consists of the components in predefined reference models of specific domains and the associations between domains and domain drivers. Because AUs enable the easy composition of a business-driven EA, the AUEA framework is agile. The semantics of the metamodel in AUEA frameworks are modeled using object-oriented and fact-oriented methods. The semantics and AUs enhance opportunities for collaboration. As an example of an AUEA in collaborative manufacturing, an EA for a supply chain on the basis of the supply-chain operations reference (SCOR) model is implemented in this paper.     

HPLC测定地榆中没食子酸和鞣花酸的含量

目的：建立RP—HPLC同时测定地榆提取物中没食子酸和鞣花酸含量的测定方法。方法：色谱柱为Shimadzu ODS C18柱（4.6mm×150mm,5μm）,流动相：甲醇-0.1%磷酸溶液梯度洗脱。检测波长280 nm,流速1.0 mL·min^-1,柱温为室温。结果：没食子酸和鞣花酸在0.2～1μg范围内线性关系良好,其平均回收率分别为98.7%和99.4%,RSD分别为1.75%和2.11%。结论：本方法操作简便,结果准确可靠,适于地榆中没食子酸和鞣花酸的同时测定。     

Auditory-model-based Feature Extraction Method for Mechanical Faults Diagnosis

It is well known that the human auditory system possesses remarkable capabilities to analyze and identify signals. Therefore, it would be significant to build an auditory model based on the mechanism of human auditory systems, which may improve the effects of mechanical signal analysis and enrich the methods of mechanical faults features extraction. However the existing methods are all based on explicit senses of mathematics or physics, and have some shortages on distinguishing different faults, stability, and suppressing the disturbance noise, etc. For the purpose of improving the performances of the work of feature extraction, an auditory model, early auditory(EA) model, is introduced for the first time. This auditory model transforms time domain signal into auditory spectrum via bandpass filtering, nonlinear compressing, and lateral inhibiting by simulating the principle of the human auditory system. The EA model is developed with the Gammatone filterbank as the basilar membrane. According to the characteristics of vibration signals, a method is proposed for determining the parameter of inner hair cells model of EA model. The performance of EA model is evaluated through experiments on four rotor faults, including misalignment, rotor-to-stator rubbing, oil film whirl, and pedestal looseness. The results show that the auditory spectrum, output of EA model, can effectively distinguish different faults with satisfactory stability and has the ability to suppress the disturbance noise. Then, it is feasible to apply auditory model, as a new method, to the feature extraction for mechanical faults diagnosis with effect.     

EA1N车轴材质高周疲劳性能研究

对国产EA1N材质车轴疲劳性能进行研究，分别对不同含碳量的EA1N车轴光滑小试样和缺口小试样进行高周旋转弯曲试验，进过107次旋转弯曲循环负载后，试样50%以上试样未有损伤或断裂。含碳量较高的试样疲劳强度更高。     

基于包络分析的灰色磁联度诊断法

利用高斯小波进行解包络分析,提取包络分析的时域特征参数,对特征参数进行模糊处理和隶属度计算,在此基础上设计出故障特征向量,进行灰色关联度分析,从而把包络解调分析、模糊数学和灰色关联分析有机结合在一起,综合它们的优势,进行故障分类和识别,为机械设备的故障诊断提供一条新的思路。     

EA4T车轴热处理工艺研究

EA4T为欧洲标准牌号的低碳合金钢材,主要应用于地铁车轴和高速动车组车轴,化学成分与国产25CrMoA钢相近,所采用的热处理工艺为调质处理。通过对其进行成分分析和反复试验,确定车轴的调质工艺为淬火温度为880—900℃,回火温度为590-610℃。     

利用神经网络实现复杂结构的多目标优化设计

结构优化设计中常常包含大量的有限元计算。现代多目标优化设计的发展趋势是以 Pareto遗传算法为代表的随机搜索方法 ,能够搜索到整个 Pareto最优解集 ,但计算量相当大 ,如果每次迭代都要涉及有限元计算 ,将是非常耗时的工作。本文在利用 Kolm ogorov多层神经网络映射存在定理的基础上导出的用神经网络进行结构近似分析的方法 ,用均匀试验设计方法选取特征样本点供神经网络训练 ,将神经网络与 Pareto遗传算法有机地结合 ,使多目标优化的计算效率进一步提高     

二维气相色谱技术分析混合碳四馏分中微量炔烃

采用二维气相色谱技术分析了混合碳四馏分中微量炔烃——乙基乙炔（EA）和乙烯基乙炔（VA）。在第一根非极性毛细管柱上进行碳四和碳五预分离,碳五以前组分通过二维色谱预切割模式,转移到第二根多孔层Al2O3开管柱上进一步分离。由于目标化合EA、VA周围没有碳五烯烃干扰,微量EA、VA很容易定性。该方法能准确定量测定微量（10-6级）碳四炔烃。分析结果对评判催化剂加氢脱炔效果起到了重要作用。     

EA1110型元素分析仪载气流量故障诊断与排除

本文阐述了EA1110型元素分析仪使用过程中出现流量故障的原因,并详细讨论了消除故障的措施。     

The equivalence in accreditation: Robust or standard statistical analysis of interlaboratory comparisons

Interlaboratory comparison (ILC) have been carried out between accredited laboratories, to improve confidence in the comparability of the measurements results obtained in different regions. In the EA framework, about 120 ILC in the different calibration field (acceleration, acoustic, electrical, force, torque, hardness, frequency, photometry, pressure, chemical analysis, etc.) were performed in the last eight years, with several thousand of Calibration Laboratories involved in these exercises. In the paper, a short synthesis of the results obtained in the APLAC-ILC Rockwell hardness test (T027) is given as an example, and compared with the results obtained in a analogous intercomparison in the EA framework (ILC-H1).     

含不同尺寸菱形压痕EA4T钢车轴的疲劳性能

采用菱形压头挤压的方式在取自EA4T钢车轴的弯曲疲劳试样上预制压痕缺陷,研究了压痕深度对疲劳强度的影响;采用修正Murakami模型预测了疲劳强度,并引入疲劳指示参数构建了疲劳寿命预测模型;采用有限元法对压痕附近的应变进行了分析。结果表明:试样的疲劳强度随压痕深度的增加而降低,与无压痕试样相比,压痕深度为0.052 mm时,疲劳强度略微降低,压痕深度为0.112,0.504 mm时,疲劳强度显著降低;疲劳裂纹萌生于应力集中较大的预制压痕短对角线处,有限元模拟结果较准确;修正的Murakami模型能较准确地预测含压痕缺陷试样的疲劳强度,构建的疲劳寿命预测模型具有较高的精度,实测值与预测值之比均在2倍误差因子范围内。     

综合定量反馈理论与特征结构配置的飞行控制系统优化设计

定量反馈理论(QFT)是一种新颖的频率域鲁棒控制技术,在N ichols图上开展分析与设计。针对大包线范围内系统模型变化大的特点,可采用QFT设计横航向控制器。由于QFT主要针对单输入单输出(SISO)系统进行分析,因此首先应采用特征结构配置(EA)理论将无人机的横航向模态进行近似解耦,将多输入多输出(M IMO)系统转化为SISO系统,再采用QFT进行控制系统设计。本文将两种控制方法结合起来,构成综合优化飞行控制方法,针对某型无人机包线范围内选取的18个状态点组成的控制对象模板进行控制设计,并进行非线性仿真。仿真结果表明设计的控制器使得无人机在全包线范围内具有较好的性能和鲁棒稳定性。     

Electron-acoustic and surface electron beam induced voltage signal formation in scanning electron microscopy analysis of semiconducting samples

The conditions for the detection of electron-acoustic (EA) and surface electron beam induced voltage (SEBIV) signals using a common sample mount and bottomside detection scheme are hereby discussed. It is shown that while the intrinsic properties of the sample under electron-beam irradiation would chiefly determine the presence of these contrast mechanisms, the manner in which the sample is mechanically and electrically configured in relation to the signal detection is crucial in determining the actual signal coupling mechanisms at work and hence the assumptions by which a robust and consistent interpretation of experimental results can be made. EA signals are detectable only if electrical coupling between the sample and the detector is defeated, a necessary pre-requisite as the signal magnitude of carrier-generated SEBIV coupling is 2-3 orders larger in most cases. With regards to SEBIV detection, bottomside SEBIV detection may be preferable to topside detection owing to minimization of topographic signal contribution, higher signal coupling efficiency and a less complex sample-detector mounting procedure.