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Comparison of continuous homogenous azeotropic and pressure-swing distillation for a minimum azeotropic system ethyl acetate/nhexane separation

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Chinese Journal of Chemical Engineering 2018年第10期26卷 2023-2033页

作者： liping lü lin Zhu Huimin liu Hang li Shirui Sun Key laboratory of Gas Process Engineering School of Chemistry and Chemical Engineering Southwest Petroleum University School of Chemistry and Chemical Engineering Yangtze Normal University

Continuous homogenous azeotropic distillation(CHAD) and pressure-swing distillation(PSD) are explored to separate a minimum-boiling azeotropic system of ethyl acetate and n-hexane. The CHAD process with acetone as the entrainer and the PSD process with the pressures of 0.1 MPa and 0.6 MPa in two columns are designed and simulated by Aspen Plus. The operating conditions of the two processes are optimized via a sequential modular approach to obtain the minimum total annual cost(TAC). The computational results show that the partially heat integrated pressure-swing distillation(HIPSD) has reduced in the energy cost and TAC by 40.79% and 35.94%, respectively, than the conventional PSD, and has more greatly reduced the energy cost and TAC by 62.61% and 49.26% respectively compared with the CHAD process. The comparison of CHAD process and partially HIPSD process illustrates that the partially HIPSD has more advantages in averting the product pollution, energy saving, and economy.

关键词： Continuous homogenous azeotropic distillation Pressure-swing distillation Ethyl acetate/n-hexane Azeotrope

Extractive distillation: Advances in conceptual design, solvent selection,and separation strategies

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Chinese Journal of Chemical Engineering 2019年第6期27卷 1247-1256页

作者： Shirui Sun liping lü Ao Yang Shun'an Wei Weifeng Shen School of Chemistry and Chemical Engineering Chongqing UniversityChongqing 400044China School of Chemistry and Chemical Engineering Yangtze Normal UniversityChongqingFuling 408100China Collaborative Innovation Center for Green Development in Wuling Moutain Area Yangtze Normal UniversityChina

Extractive distillation(ED) is one of the most promising approaches for the separation of the azeotropic or closeboiling mixtures in the chemical industry. The purpose of this paper is to provide a broad overview of the recent development of key aspects in the ED process involving conceptual design, solvent selection, and separation strategies. To obtain the minimum entrainer feed flow rate and reflux ratio for the ED process, the conceptual design of azeotropic mixture separation based on a topological analysis via thermodynamic feasibility insights involving residue curve maps, univolatility lines, and unidistribution curves is presented. The method is applicable to arbitrary multicomponent mixtures and allows direct screening of design alternatives. The determination of a suitable solvent is one of the key steps to ensure an effective and economical ED process. Candidate entrainers can be obtained from heuristics or literature studies while computer aided molecular design(CAMD) has superiority in efficiency and reliability. To achieve optimized extractive distillation systems, a brief review of evaluation method for both entrainer design and selection through CAMD is presented. Extractive distillation can be operated either in continuous extractive distillation(CED) or batch extractive distillation(BED), and both modes have been well-studied depending on the advantages in flexibility and low capital costs. To improve the energy efficiency, several configurations and technological alternatives can be used for both CED and BED depending on strategies and main azeotropic feeds. The challenge and chance of the further ED development involving screening the best potential solvents and exploring the energy-intensive separation strategies are discussed aiming at promoting the industrial application of this environmentally friendly separation technique.

关键词： Extractive distillation Separation strategies Solvent selection Conceptual design

基于改进秃鹰搜索算法的工业机器人几何参数标定方法

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机械设计与研究 2022年第6期38卷 21-24,33页

作者：黄维吕丽平武汉职业技术学院电子信息工程学院武汉430074 郑州升达经贸管理学院信息工程学院郑州451191

为提高工业机器人末端定位精度,提出了基于改进秃鹰搜索算法(IBES)的工业机器人几何参数标定方法。首先,建立了6自由度串联机器人几何参数标定的数学模型;其次,针对机器人几何参数标定的特点,对秃鹰搜索算法(BES)进行改进,提出用改进秃... 详细信息

为提高工业机器人末端定位精度,提出了基于改进秃鹰搜索算法(IBES)的工业机器人几何参数标定方法。首先,建立了6自由度串联机器人几何参数标定的数学模型;其次,针对机器人几何参数标定的特点,对秃鹰搜索算法(BES)进行改进,提出用改进秃鹰搜索算法(IBES)优化标定机器人几何参数,并明确了主要步骤。其中,IBES在BES中融入了levy飞行策略,改善了算法收敛效果,具有了跳出局部最优能力;最后,通过机器人几何参数标定仿真实验和实测实验对所提方法的有效性进行了验证。

关键词：秃鹰搜索算法 levy飞行策略工业机器人几何参数标定

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基于多视角聚类的WiFi指纹定位方法研究

传感技术学报 2021年第5期34卷 690-695页

作者：马宗方吕丽萍田鸿朋王艳西安建筑科技大学信息与控制工程学院陕西西安710055

为了解决在基于聚类方法的WiFi指纹定位中视角单一所导致的定位精度较低的问题,提出了基于多视角聚类的WiFi指纹定位方法。利用阈值-均值滤波方法对原始数据进行处理;结合K-means聚类算法对多视角信号(信号强度和位置)进行区划,并建立... 详细信息

为了解决在基于聚类方法的WiFi指纹定位中视角单一所导致的定位精度较低的问题,提出了基于多视角聚类的WiFi指纹定位方法。利用阈值-均值滤波方法对原始数据进行处理;结合K-means聚类算法对多视角信号(信号强度和位置)进行区划,并建立离线指纹库;使用基础分类器对实测信号分类,待测信号依据分类结果在其所属区域内估计K个邻近信号点,用近邻以及相应的权重值综合确定该信号的实际位置。通过对比实验分析可知,在考虑多视角的情况下,WiFi指纹定位精度在4 m以内的概率为83%,相比于单视角聚类的定位精度提高了12%。结果表明,该方法提高了定位精度,也为定位领域的研究提供了多元化思路。

关键词：无线传感器网络 WiFi指纹定位多视角聚类定位精度

Treadmill exercise in combination with acousto-optic and olfactory stimulation improves cognitive function in APP/PS1 mice through the brain-derived neurotrophic factor-and Cygb-associated signaling pathways

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Neural Regeneration Research 2025年第9期20卷 2706-2726页

作者： Biao Xiao Chaoyang Chu Zhicheng lin Tianyuan Fang Yuyu Zhou Chuxia Zhang Jianghui Shan Shiyu Chen liping li Department of Physiology and Pharmacology Health Science CenterNingbo UniversityNingboZhejiang ProvinceChina Ningbo Key laboratory of Behavioral Neuroscience Health Science CenterNingbo UniversityNingboZhejiang ProvinceChina Key laboratory of Addiction Research of Zhejiang Province NingboZhejiang ProvinceChina

A reduction in adult neurogenesis is associated with behavioral abnormalities in patients with Alzheimer's ***,enhancing adult neurogenesis represents a promising therapeutic approach for mitigating disease symptoms and ***,nonpharmacological interventions aimed at inducing adult neurogenesis are currently *** individual non-pharmacological interventions,such as aerobic exercise,acousto-optic stimulation,and olfactory stimulation,have shown limited capacity to improve neurogenesis and cognitive function in patients with Alzheimer's disease,the therapeutic effect of a strategy that combines these interventions has not been fully *** this study,we observed an age-dependent decrease in adult neurogenesis and a concurrent increase in amyloid-beta accumulation in the hippocampus of amyloid precursor protein/presenilin 1 mice aged 2-8 *** deposition became evident at 4 months,while neurogenesis declined by 6 months,further deteriorating as the disease ***,following a 4-week multifactor stimulation protocol,which encompassed treadmill running(46 min/d,10 m/min,6 days per week),40 Hz acousto-optic stimulation(1 hour/day,6 days/week),and olfactory stimulation(1 hour/day,6 days/week),we found a significant increase in the number of newborn cells(5'-bromo-2'-deoxyuridine-positive cells),immature neurons(doublecortin-positive cells),newborn immature neurons(5'-bromo-2'-deoxyuridine-positive/doublecortin-positive cells),and newborn astrocytes(5'-bromo-2'-deoxyuridine-positive/glial fibrillary acidic protein-positive cells).Additionally,the amyloid-beta load in the hippocampus *** findings suggest that multifactor stimulation can enhance adult hippocampal neurogenesis and mitigate amyloid-beta neuropathology in amyloid precursor protein/presenilin 1 ***,cognitive abilities were improved,and depressive symptoms were alleviated in amyloid precursor protein/presenilin 1 mice

关键词： acousto-optic stimulation adult neurogenesis Alzheimer's disease amyloid precursor protein/presenilin 1 mice amyloid-beta deposition brain cell apoptosis cognitive impairment depression-like behavior involuntary treadmill exercise olfactory stimulation serum metabolites

一种宽带输入和性能可调的低噪声放大器的设计

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电子器件 2023年第4期46卷 906-913页

作者：熊绍刚吕丽平襄阳职业技术学院商学院湖北襄阳441050 郑州升达经贸管理学院信息工程学院河南郑州451191

提出了一种宽调谐范围的性能可调低噪声放大器。它由2级构成,第一级以宽带输入匹配和低噪声放大为主,采用一种新的开关电感结构来获得宽范围的频率调谐,而增益和噪声系数保持在相同的水平;第二级为具有性能可调的宽调谐范围限带增益响应... 详细信息

提出了一种宽调谐范围的性能可调低噪声放大器。它由2级构成,第一级以宽带输入匹配和低噪声放大为主,采用一种新的开关电感结构来获得宽范围的频率调谐,而增益和噪声系数保持在相同的水平;第二级为具有性能可调的宽调谐范围限带增益响应,通过偏置控制和晶体管尺寸切换来实现;最后,基于提出的技术,采用0.12μm CMOS制作工艺,实现了一种2.3 GHz~5.5 GHz的CMOS低噪声放大器。在1.1 V电源电压下,具有包括高达24.8 dB的功率增益、低于3.0 dB的噪声系数和小于4.5 mW功耗的性能,无焊盘核心电路仅占0.4 mm2的芯片面积。

关键词：多标准无线电宽调谐范围低噪声放大器双无功反馈开关电感性能可调频率响应

动态计算实时参数的T型线路沿线电压交叉修正故障测距算法

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电网技术 2020年第2期44卷 761-768页

作者：李振兴张健婷陈艳霞翁汉琍吕立平三峡大学电气与新能源学院湖北省宜昌市443002 国网北京市电力公司电力科学研究院北京市丰台区100075

T型线路改变了线路的非均匀性,因此提高其故障测距精度历来是研究热点。为解决参数误差对测距精度的影响,利用系统正常运行状态下的电气信息,动态实时计算线路参数,并基于遗传算法修正参数的误差。进一步在此基础上,提出了一种沿线电压... 详细信息

T型线路改变了线路的非均匀性,因此提高其故障测距精度历来是研究热点。为解决参数误差对测距精度的影响,利用系统正常运行状态下的电气信息,动态实时计算线路参数,并基于遗传算法修正参数的误差。进一步在此基础上,提出了一种沿线电压交叉修正故障测距方法。基于分布参数线路模型,分析输电线路的沿线电压幅值分布规律,并结合直线交叉原理进行故障支路预判与故障测距初判,进而通过少数次迭代和校正,达到故障测距的高精度定位。仿真分析结果表明,该算法测距原理简单,迭代次数少,收敛速度快,且测距精度不受故障类型、故障电阻及负荷等的影响。

关键词： T型输电线路参数调节故障测距直线交叉

基于定量结构-性质关系预测含水二元共沸物的共沸温度与组成

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化学工业与工程 2020年第4期37卷 30-39页

作者：曾行艳诸林吕利平李兵西南石油大学化学化工学院成都610500 长江师范学院化学化工学院重庆408100

以125种含水二元共沸物为研究对象,基于定量结构-性质关系,对该类共沸物在常压下的共沸温度及组成进行了预测研究,分别建立了多个预测模型。首先,利用HyperChem 8.0软件绘制了纯组分的三维分子结构,并利用分子力学方法和量子力学半经验... 详细信息

以125种含水二元共沸物为研究对象,基于定量结构-性质关系,对该类共沸物在常压下的共沸温度及组成进行了预测研究,分别建立了多个预测模型。首先,利用HyperChem 8.0软件绘制了纯组分的三维分子结构,并利用分子力学方法和量子力学半经验方法对分子结构进行优化;然后,利用Materials Studio 8.0软件计算纯物质的分子描述符;其次,利用遗传算法分别筛选出与共沸温度及组成最为密切的特征描述符;再运用多元线性回归方法建立了6个共沸温度预测模型及5个共沸组成预测模型,并对模型的稳定性、拟合能力和预测能力进行对比分析;最后,对最适宜模型分别进行内部验证、外部验证、应用域分析、与文献中同类模型及UNIFAC基团贡献法进行对比。结果表明:最适宜共沸温度/组成预测模型分别是利用8/5个特征描述符所建立的模型;其复相关系数,调整复相关系数,均方根误差,平均绝对误差,留一法交叉验证系数和外部验证系数分别为0.9606/0.9970、0.9572/0.9969、2.9400/0.0161、1.8900/0.0104、0.9475/0.9957和0.9439/0.9976,且模型的稳定性、预测能力和泛化能力均优同类模型。

关键词：定量结构-性质关系(QSPR) 共沸温度共沸组成预测含水二元共沸物

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强化脱氮工艺在污水处理中的研究与应用进展

工业水处理 2021年第8期41卷 20-24,91页

作者：李航董立春吕利平重庆大学化学化工学院重庆401331 重庆市三峡水务渝北排水有限责任公司重庆401120 长江师范学院化学化工学院重庆408100

水体富营养化已成为全球性的水污染问题,氮在水体中的富集是富营养化的主要因素。作为资源节约与环境友好型脱氮工艺,强化脱氮工艺具有能耗小、成本低、效率高等优点。然而,强化脱氮工艺也存在启动时间长、稳定运行难、菌种增殖慢、环... 详细信息

水体富营养化已成为全球性的水污染问题,氮在水体中的富集是富营养化的主要因素。作为资源节约与环境友好型脱氮工艺,强化脱氮工艺具有能耗小、成本低、效率高等优点。然而,强化脱氮工艺也存在启动时间长、稳定运行难、菌种增殖慢、环境依附度高等问题,严重阻碍了其规模化应用。综述了强化脱氮工艺在污水处理中的应用研究现状,介绍了强化工艺的原理、优势、影响因素及适用条件,并对运行较成功的工程案例进行分析说明。在此基础上提出强化工艺的下一步研究重点,包括:具有广泛适应性的短程硝化反硝化污水处理工艺的开发,厌氧氨氧化菌的快速增殖与稳定保留,从分子生物学层面开展好氧颗粒污泥形成机理探究及稳定运行控制条件的优化。

关键词：脱氮短程硝化反硝化厌氧氨氧化好氧颗粒污泥