Phase equilibrium data prediction and process optimizationin butadiene extraction process

In response to the lack of reliable physical parameters in the process simulation of the butadiene extraction,a large amount of phase equilibrium data were collected in the context of the actual process of butadiene production by acetonitrile.The accuracy of five prediction methods,UNIFAC(UNIQUAC Functional-group Activity Coefficients),UNIFAC-LL,UNIFAC-LBY,UNIFAC-DMD and COSMO-RS,applied to the butadiene extraction process was verified using partial phase equilibrium data.The results showed that the UNIFAC-DMD method had the highest accuracy in predicting phase equilibrium data for the missing system.COSMO-RS-predicted multiple systems showed good accuracy,and a large number of missing phase equilibrium data were estimated using the UNIFAC-DMD method and COSMO-RS method.The predicted phase equilibrium data were checked for consistency.The NRTL-RK(non-Random Two Liquid-Redlich-Kwong Equation of State)and UNIQUAC thermodynamic models were used to correlate the phase equilibrium data.Industrial device simulations were used to verify the accuracy of the thermodynamic model applied to the butadiene extraction process.The simulation results showed that the average deviations of the simulated results using the correlated thermodynamic model from the actual values were less than 2%compared to that using the commercial simulation software,Aspen Plus and its database.The average deviation was much smaller than that of the simulations using the Aspen Plus database(>10%),indicating that the obtained phase equilibrium data are highly accurate and reliable.The best phase equilibrium data and thermodynamic model parameters for butadiene extraction are provided.This improves the accuracy and reliability of the design,optimization and control of the process,and provides a basis and guarantee for developing a more environmentally friendly and economical butadiene extraction process.

Unexpected Twinning and Phase-Transition of the Indentation Standards, Their Transition Energies, and Scientific Dichotomy

The general use of aluminium as an indentation standard for the iteration of contact heights for the determination of ISO-14577 hardness and elastic modulus is challenged because of as yet not appreciated phase-changes in the physical force-depth standard curve that seemed to be secured by claims from 1992. The physical and mathematical analyses with closed formulas avoid the still world-wide standardized energy-law violation by not reserving 33.33% (h2 belief) (or 20% h3/2 physical law) of the loading force and thus energy for all not depth producing events but using 100% for the depth formation is a severe violation of the energy law. The not depth producing part of the indentation work cannot be done with zero energy! Both twinning and structural phase-transition onsets and normalized phase-transition energies are now calculated without iterations but with physically correct closed arithmetic equations. These are reported for Berkovich and cubecorner indentations, including their comparison on geometric grounds and an indentation standard without mechanical twinning is proposed. Characteristic data are reported. This is the first detection of the indentation twinning of aluminium at room temperature and the mechanical twinning of fused quartz is also new. Their disqualification as indentation standards is established. Also, the again found higher load phase-transitions disqualify aluminium and fused quartz as ISO-ASTM 14577 (International Standardization Organization and American Society for Testing and Materials) standards for the contact depth “hc” iterations. The incorrect and still world-wide used black-box values for H- and Er-values (the latter are still falsely called “Young’s moduli” even though they are not directional) and all mechanical properties that depend on them. They lack relation to bulk moduli from compression experiments. Experimentally obtained and so published force vs depth parabolas always follow the linear FN = kh3/2 + Fa equation, where Fa is the axis-cut before and after the phase-transition branches (never “h2” as falsely enforced and used for H, Er and giving incorrectly calculated parameters). The regression slopes k are the precise physical hardness values, which for the first time allow for precise calculation of the mechanical qualities by indentation in relation to the geometry of the indenter tip. Exactly 20% of the applied force and thus energy is not available for the indentation depth. Only these scientific k-values must be used for AI-advises at the expense of falsely iterated indentation hardness H-values. Any incorrect H-ISO-ASTM and also the iterated Er-ISO-ASTM modulus values of technical materials in artificial intelligence will be a disaster for the daily safety. The AI must be told that these are unscientific and must therefore be replaced by physical data. Iterated data (3 and 8 free parameters!) cannot be transformed into physical data. One has to start with real experimental loading curves and an absolute ZerodurR standard that must be calibrated with standard force and standard length to create absolute indentation results. .

Mechanical Fault Diagnosis Based on Band-phase-randomized Surrogate Data and Multifractal

The vibration signals of machinery with various faults often show clear nonlinear characteristics.Currently,fractal dimension analysis as the common useful method for nonlinear signal analysis,is a kind of single fractal form,which only reflects the overall irregularity of signals,but cannot describe its local scaling properties.For comprehensive revealing of internal properties,a combinatorial method based on band-phase-randomized（BPR） surrogate data and multifractal is introduced.BPR surrogate data method is effective to eliminate nonlinearity in specified frequency band for a fault signal,which can be utilized to detect nonlinear degree in whole fault signal by nonlinear titration method,and the overall nonlinear distribution of fault signal is displayed in nonlinear characteristic curve that can be used to analyze the fault signal qualitatively.Then multifractal theory as a quantitative analysis method is used to describe geometrical characteristics and local scaling properties,and asymmetry coefficient of multifractal spectrum and multifractal entropy for fault signals are extracted as new criterions to diagnose machinery faults.Several typical faults include rotor misalignment,transversal crack,and static-dynamic rubbing fault are analyzed,and the results indicate that those faults can be distinguished by the proposed method effectively,which provides a qualitative and quantitative analysis way in the field of machinery fault diagnosis.

Unconventional phase transition of phase-change-memory materials for optical data storage

Recent years, optically controlled phase-change memory draws intensive attention owing to some advanced applications including integrated all-optical nonvolatile memory, in-memory computing, and neuromorphic computing. The light-induced phase transition is the key for this technology. Traditional understanding on the role of light is the heating effect. Generally, the RESET operation of phase-change memory is believed to be a melt-quenching-amorphization process. However, some recent experimental and theoretical investigations have revealed that ultrafast laser can manipulate the structures of phase-change materials by non-thermal effects and induces unconventional phase transitions including solid-to-solid amorphization and order-to-order phase transitions. Compared with the conventional thermal amorphization,these transitions have potential superiors such as faster speed, better endurance, and low power consumption. This article summarizes some recent progress of experimental observations and theoretical analyses on these unconventional phase transitions. The discussions mainly focus on the physical mechanism at atomic scale to provide guidance to control the phase transitions for optical storage. Outlook on some possible applications of the non-thermal phase transition is also presented to develop new types of devices.

Research on Data Combination for Phased-Array Ground Penetrating Radar

To resolve the data combination of Phased-array Ground Penetrating Radar (PAGPR), we first build a model of PAGPR and a layered model, and then a new data combination algorithm is presented based on it. This method calculates time delay of multi-receivers, basing on the signal of the nearest receiver, then shifts other signals and adds them up, and gets one signal at last. It has been proved that this method can restrain noise, multiple waves, clutter waves and improve the precision of time location. In the end, an example is given to prove the method's efficiency.

Thermodynamic data calculation for iron phases in sulfoaluminate cementitious materials prepared using solid wastes

The preparation of sulfoaluminate cementitious materials(SCM)is a promising way to massively utilize solid wastes.Iron phases are significant in SCM system but the thermodynamic data of some key minerals,such as6 CaO·Al2 O3·2 Fe2 O3(C6 AF2)and 6 CaO·2 Al2 O3·Fe2 O3(C6 A2 F),are missing,which greatly hinders the SCM optimization in a theoretical way.This work,for the first time,calculated the standard formation enthalpy,Gibbs free energy of formation,entropy and molar heat capacity for C6 AF2 and C6 A2 F and lowered the errors to the least with the reference of C4 AF data in the literature.By building the function diagram of Gibbs free energy changes with temperature for the basic iron phase formation reactions with the obtained thermodynamic data,it is proved that the formation likeliness of C6 AF2 is higher than that of C6 A2 F,as is accordant to the literatures and verifies the correctness of obtained data.This work provides a good theoretical foundation to optimize SCM mineral system and to study relevant mechanism deeply.

ASSESSMENT AND OPTIMIZATION OF THE PHASE DIAGRAMS AND THERMODYNAMIC DATA OF SOME BINARY SYSTEMS CONTAINING PRASEODYMIUM CHLORIDES

In this paper a critical assessment and optimization of the phase diagrams and thermodynamic properties of the PrCl_3-MCl(M=Li,Na)and PrCl_3-MCl_2(M=Mg,Ca,Sr,Ba) binary systems have been per- formed.The assessed and optimized binary phase diagrams and thermodynamic data with self consistency are a better basis for constructing multicomponent phase diagrams.

Wigner Frequency Point Slice Analysis of Superposition Data for Phased-Array Ground Penetrating Radar

According to the frequency property of Phasedarray ground penetrating radar (PGPR), this paper gives a frequency point slice method based on Wigner time-frequency analysis. This method solves the problem of analysis for the PGPR's superposition data and makes detecting outcome simpler and detecting target more recognizable. At last, the analytical results of road test data of the Three Gorges prove the analytical method efficient. Key words phased-array ground penetrating radar - wigner time-frequency analysis - superposition data - object identification CLC number TN 715.7 Foundation item: Supported by the National Nature Science Foundation of China (50099620) and 863 Program Foundation of China (2001AA132050-03)Biography: ZOU Lian (1975-), male, Ph. D candidate, research direction: signal processing.

基于地震频相融合的智能化高分辨率反演

目前的地震反演主要以模型驱动为主,对噪声较敏感,反演结果的分辨率往往较低,通常只使用地震数据的振幅信息,没有充分利用相位信息。研究表明,波阻抗和地震振幅、相位的相关性较强,因此联合应用振幅谱和相位谱可以有效减小反演结果的多解性。为此,结合深度学习与地震数据的频(振幅谱)、相(相位谱)信息,提出基于数据驱动的频相智能波阻抗反演,有效提高了反演结果的分辨率和精度。具体步骤为:(1)基于高分辨率时频分析提取地震道的频相信息;(2)应用图像处理技术融合频相信息;(3)结合频相信息和地层波阻抗制作数据标签对,用数据标签对训练优选的深度网络;(4)提取待反演三维地震数据的频相信息并输入训练好的深度网络,即可得到高分辨率波阻抗反演结果。与现有的深度学习地震反演方法相比,所提方法主要创新点在于首次在地震反演中同时应用了地震数据的频相信息。模型测试结果表明,频相信息的联合应用有效地减小了反演结果的多解性,提高了反演精度。实际应用结果表明,与传统的稀疏脉冲反演相比,所提方法提高了反演结果的纵向分辨率,益于进一步推广、应用。

段塞流分相流量的多传感器信息融合测量

气液两相流广泛存在于能源化工领域,由于两相流流动特性复杂多变,为流量准确测量带来了极大困难。为了建立准确的气液两相流量测量模型,针对气液两相段塞流分相流量测量,充分利用声发射传感器捕获气液两相流动噪声的功能和近红外吸收会因介质类别产生较大差异的特性,设计了一种新型测量传感器。在文丘里管的喉管和延伸段分别安装两组声发射探头,并在文丘里管的喉管处安装两组近红外光电探测器。设计了声发射与近红外同步采集系统,以水平管段塞流为实验对象,在河北大学高精度气液两相循环装置上完成了54组段塞流试验的数据采集,并进行融合处理,得到气液两相流特征参数。引入时域分析方法,提取声发射与近红外测量数据的标准差与偏斜度。结合参数拟合方法,建立两相流流量预测模型并进行误差分析。经验证,92.6%的流量预测值的相对偏差在±20%以内。结果表明,基于声发射传感器与近红外传感器的多传感器信息融合方案为气液两相流流动特征参数研究提供了一种新的思路。

Method of Phase Diagrams for the Analysis of Seism-Acoustical Spatial-Time Monitoring Data in Oil Wells

Experimental and theoretical studies of the mechanisms of vibration stimulation of oil recovery in watered fields lead to the conclusion that resonance oscillations develop in fractured-block formations. These oscillations, caused by weak but long-lasting and frequency-stable influences, create the conditions for ultrasonic wave’s generation in the layers, which are capable of destroying thickened oil membranes in reservoir cracks. For fractured-porous reservoirs in the process of exploitation by the method of water high-pressure oil displacement, the possibility of intensifying ultrasonic vibrations can have an important technological significance. Even a very weak ultrasound can destroy, over a long period of time, the viscous oil membranes formed in the cracks between the blocks, which can be the reason for lowering the permeability of the layers and increasing the oil recovery. To describe these effects, it is necessary to consider the wave process in a hierarchically blocky environment and theoretically simulate the mechanism of the appearance of self-oscillations under the action of relaxation shear stresses. For the analysis of seism acoustic response in time on fixed intervals along the borehole an algorithm of phase diagrams of the state of many-phase medium is suggested.

基于相移的三维扫描数据自动配准方法研究

在三维扫描过程中,常因受到设备自身因素与点云丢失的限制而难以一次性完成数据采集。为准确实现物体三维模型重构,提出基于相移的三维扫描数据自动配准方法。首先设置旋转台,利用非接触式结构光方法获得转动轴的有关信息,从而采集目标点云数据。在此基础上,结合任意一点与其周围点曲率信息建立曲率图,对全部顶点做曲率运算,将数据划分为连续子块,计算每个子块中平均值和方差,从而提取关键特征点。然后获取两幅具有部分重叠关系图像的相对位移,采用交叉功率谱的傅里叶变换完成位移估计,再通过构造与组合点对、粗略与精确配准去除噪声点,实现三维扫描数据自动配准。仿真实验表明,该方法能够在确保配准精度的同时提高配准方法的运行效率,可靠性和实用性较强。

用于新型符号的频偏补偿和解调的算法与电路

为提高传统脉冲位置调制(pulse position modulation,PPM)符号的频谱效率,提出了一种新型码片内4-PPM符号调制方法,在实现1 Gbit/s通信速率的同时,又大大减少所需频谱资源。可在解调时,该符号调制的误码率性能受到发射端时钟和接收端本地时钟之间的频率偏移的极大影响。针对此问题,又提出了一种在模拟域对该符号进行频偏补偿,并实现符号同步和高速数据解调的算法与电路。该电路系统通过消除接收数据和本地时钟的初始相差、提取两者的频偏信息、周期性改变本地时钟的瞬时相位3步实现频偏补偿,并同时在第3步利用本地时钟对接收数据进行解调。为提高相位插值器(phase interpolator,PI)的线性度,本文将延迟锁定环与PI相结合。在2π的插值范围内,实现插值区间32个,插值步长992个,分辨率2.016 ps,最大差分非线性(differential nonlinearity,DNL)0.183°,最大积分非线性(integral nonlinearity,INL)0.325°。此外,本文提出的相位控制算法有效避免了由电流毛刺所引起的输出相位突变。电路基于UMC 40 nm CMOS RF LP工艺进行设计与仿真。仿真结果表明:本文所提出的算法与电路,在典型工艺角下,将接收数据和本地时钟间的50×10^(-6)频率偏差度降至1.03×10^(-6),频偏补偿准确度达到97.94%,并实现1 Gbit/s的解调速率。该方法对高速PPM数据同步与解调具有良好的工程应用价值。

高明利教授治疗痛风性关节炎急性期的用药规律

目的:应用数据挖掘的科研方法分析高明利教授辨治痛风性关节炎急性期的药物组方原则及用药规律,为临床用药提供科学的依据。方法:收集2017年1月15日至2021年12月15日在辽宁中医药大学附属医院风湿科高明利教授门诊就诊的206例痛风性关节炎急性期患者的病例数据及首诊处方,对性别、年龄、四气五味、归经、药物功效、药物的频次进行分析;采用软件IBM SPSS Modeler 18.0、SPSS 26.0对数据进行复杂网络分析、关联规则分析及聚类分析。结果:对206例病例数据进行整理,男女比为40∶1,涉及药物135味,频次最高的药物为萆薢、泽泻、知母、薏苡仁;四气多为寒、平、温;五味多为苦、甘、辛,归经多为肾、胃、肝三经。药物类别清热药、利水渗湿药、祛风湿药应用居多。关联规则分析得出常用药对及药物组,高频药物聚类分析共聚5大类。结论:高明利教授治疗痛风性关节炎急性期以清热药、利水渗湿药及祛风湿药为基准,重用清热药与利水渗湿药,用以清热利湿、通络止痛,在性味归经上重用苦寒之品,多选择从肾经上加以干预,治疗多以清热利湿为中心,佐用健脾、活血、引经、补益、解表、散结、止痛等药物。

基于GA的RBF神经网络气液两相流持液率预测模型优化

为了提高气液两相流持液率预测精度,针对传统径向基函数(RBF)神经网络预测气液两相流持液率网络拓扑结构困难和收敛速度慢等问题,提出一种基于遗传算法(GA)优化径向基函数神经网络的气液两相流持液率预测模型。通过系统聚类算法和灰色关联度分析(GRA)对收集的实验数据进行处理,优选出最优模型特征,同时结合遗传算法确定了RBF神经网络结构参数。基于室内实验数据进行训练,并与常用于持液率预测的反向传播(BP)神经网络、GA-BP神经网络及RBF神经网络进行对比,评估了模型的准确性及可行性。结果表明:GA-RBF神经网络模型均方误差为0.0017,均方根误差为0.0416,平均绝对误差为0.0281,拟合度为0.9483。相较于其他神经网络模型,该预测模型表现出更高的计算精度和更强的泛化能力。

基于数据挖掘探讨肖承悰治疗黄体功能不全性不孕的用药规律

目的利用数据挖掘技术分析肖承悰教授治疗黄体功能不全性不孕的用药规律,探讨其临证经验。方法收集2007年12月-2021年12月肖承悰教授门诊患者病历资料,筛选后录入FangNet平台,通过频次统计、协同性分级、药物-症状关联、药物聚类、性味归经等对用药规律进行分析。结果共纳入病案90则,涉及患者90例、处方270首。肖承悰教授治疗黄体功能不全性不孕高频药物包括桑寄生、续断、巴戟天、茯苓、女贞子等,药性多温、平,药味以甘为主,主归肾经、肝经。药物聚类分析显示,桑寄生、续断、巴戟天为主要药对。结论肖承悰教授认为,黄体功能不全性不孕的病机为肾阳亏虚,治以温肾助阳为主,兼以养肝健脾,调理冲任;用药强调药性平和,临床中擅用药对,展现了燕京萧氏妇科“和合灵动”的学术思想。

电力电缆局放在线监测神经网络自动识别精度的提升方法

为了尽可能降低电缆线路局放在线监测系统装置运行中对局放信号识别的误判误报的可能性,对局放的判读机理和识别精度进行了改进和提升。基于现场运行系统回收的数万个疑似电缆内部局放的告警记录数据进行了分析分类,对判别程序中沿用的局放自动逻辑判别程序追加了相间信号相关性过滤程序,对既有的神经网络在构造上作了优选优化,对神经网络学习数据的前置处理进行了改进。对改进提升后的局放判别程序采用了包括现场记录,模拟信号发生器和人工局放模型加电压实验的3种局放数据进行检验。结果表明,改进提升后的局放判别程序不但能够使现场的非局放告警数据的告警率降低到5%的期待水平,同时也提高了识别人工模拟产生的各种类型局放信号的准确性,大大降低了局放在线监测系统误判误报的可能性。

基于集成学习和信息融合的段塞流分相流量测量

段塞流是气液两相流中典型流型,准确测量其分相流量有利于实时监控生产过程,优化工艺控制,确保系统在安全、经济的工况下运行.本文在改进长喉文丘里管的基础上,设计了一种集近红外(NIR)、声发射(AE)技术于一体的水平气液流量智能多传感系统.利用AE传感器和NIR传感器检测气液两相的流动噪声信息和截面信息,采用经验模态分解法(EMD)提取气体体积分数的特征变量.通过集成学习算法进行特征级融合,融合后的段塞流体积含气率预测模型平均绝对百分比误差(MAPE)为4.11%,92.45%的预测结果偏差在±10%以内.在Collins模型的基础上,提出了基于梯度提升决策树(GBDT)的段塞流质量流量预测模型,其MAPE值为0.96%,全部预测结果的偏差在±20%以内.本研究为气液两相流段塞流参数混合不分离测量提供了一种新方法,为气液两相流动机理研究奠定了基础.

大数据税收征管与审计质量——基于“金税三期”工程准自然实验

“金税三期”工程在全国范围内实现涉税数据的大集中,对企业审计质量起着重要的影响。以2010—2022年全部A股上市公司为研究样本,基于“金税三期”工程准自然实验,构建双重差分模型,考察大数据税收征管如何影响企业的审计质量,并揭示二者之间的作用机理和在不同环境下的影响效果。研究发现:大数据税收征管有效提高了审计质量。机制检验表明,大数据税收征管通过降低注册会计师的业务风险和审计风险,从而提高审计质量。进一步分析发现,在国有企业和法治环境较好的地区,大数据税收征管提高审计质量的效果更为显著。

压力波发生器的调制与控制方法研究

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