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Simulation on Thermal Integrity of the Fin/Tube Brazed Joint of Heat Exchangers

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Journal of Materials Science & Technology 2003年第Z1期19卷 71-72页

作者： Yiyu qian feng GAO fengjiang WANG Hui ZHAO State Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 China State Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 China State Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 China State Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 China

In the applications of heat exchangers, the fin efficiency of heat transfer is the key issue. Thermal distribution withinthe brazed joints in heat exchanger under loading conditions is investigated in this paper. Simulated results showedthat the thermal distribution at the brazed joint zone is related to not only the geometry of the fin and tube, butalso the brazed joint topology. A poor brazed joint will result in very poor heat transfer. Thermal contact resistanceis adopted to analyze the fin heat efficiency.

关键词： Thermal integrity, Fin efficiency, Thermal contact resistance, FEM

Synthesis and Structure of an Octopus-like Octapropargyl Tetra-iso-butyl-resorcin[4]arene

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Chinese Journal of Structural Chemistry 2005年第8期24卷 952-956页

作者： LIU Xiang LIU Yu-Jie ZHANG qian-feng Department of Applied Chemistry School of Chemical Engineering and Chemistry Anhui University of Technology ChinaMaanshan Anhui 243002

Treatment of tetra-iso-butyl-resorcin[4]arene 1 with propargyl bromide in the presence of K2CO3 as base gave an octopus-like octapropargyl tetra-iso-butyl-resorcin[4]arene 2 （C68H72O8, Mr = 1017.26） in a quantitative yield. Single-crystal structure of 2 was determined by X-ray crystallography. 2 crystallizes in the monoclinic system, space group P21/n with a =13.3247（6）, b = 24.7929（11）, c = 19.1810（9）A°, β = 109.272（1）°, V= 5981.5（5） A°^3, Dc = 1.130g/cm^3,μ = 0.073 mm^-1, F（000） = 2176 and Z = 4. Overall structure of 2 reveals an octopus-like resorcinarene with eight propargyl groups in different directions. The resorcinarene adopts the boat conformation where the iso-butyl residues act as four-legged piano stool. The two opposite aryl rings of the macrocyclic framework are almost coplanar, and the two others facing each other are perpendicular to this plane.

关键词： resorcinarene propargyl crystal structure supramolecular chemistry

Electrical characteristics of AlGaN/GaN metal-insulatorsemiconductor high electron mobility transistor using La2O3 gate dielectric

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Science China Technological Sciences 2013年第3期56卷 629-632页

作者： feng qian WANG qiang XING Tao LI qian HAO Yue Key Laboratory of Wide Band-Gap Semiconductor Materials and Devices School of MicroelectronicsXidian University

We report the studies of AlGaN/GaN metal-insulator-semiconductor high electron mobility transistors(MISHEMTs) using reactive-sputtered La2O3 as the gate dielectric and the surface passivation *** device presents a maximum drain current of 829 mA/mm and a maximum transconductance of 105 mS/mm,while the gate leakage current in the reverse direction is reduced by two orders of magnitude and the forward gate voltage swing increased to +5 V without gate *** to HEMT devices of similar geometry,MISHEMTs present a significant drain current recovery form current collapse.

关键词： gallium nitride metal-insulator-semiconductor high electron mobility transistor(MISHEMT) lanthanum oxide

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数字赋能:终身学习视域下的学分银行建设

湖北第二师范学院学报 2024年第8期41卷 111-116页

作者：袁舒雯陈雨倩王傲斐钱丰收安徽开放大学合肥230022

在终身学习视域下推进学分银行建设,是推动学习型社会、学习型大国的有力支撑,与终身学习文化发展相得益彰,是实现个体生命整全性的坚实保障。当前,我国学分银行建设面临着五个层面的发展困境。为发挥学分银行服务终身学习的时代使命,... 详细信息

在终身学习视域下推进学分银行建设,是推动学习型社会、学习型大国的有力支撑,与终身学习文化发展相得益彰,是实现个体生命整全性的坚实保障。当前,我国学分银行建设面临着五个层面的发展困境。为发挥学分银行服务终身学习的时代使命,赋能“三教”协同创新发展,需从理念、实践、制度、标准及评价等五个方面寻求提升突破的路径。

关键词：学分银行终身学习数字赋能

A Multi-Agent Immune Network Algorithm and Its Application to Murphree Efficiency Determination for the Distillation Column

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Journal of Bionic Engineering 2011年第2期8卷 181-190页

作者： Xuhua Shi feng qian State Key Laboratory qf Chemical Engineering East China University of Science and Technology Shanghai 200237 P. R. China College of Information Science and Engineering Ningbo University Ningbo 315211 P. R. China

Artificial Immune Network （aiNet） algorithms have become popular for global optimization in many modem industrial applications. However, high-dimensional systems using such models suffer from a potential premature convergence problem. In the existing aiNet algorithms, the premature convergence problem can be avoided by implementing various clonal selection methods, such as immune suppression and mutation approaches, both for single population and multi-population cases. This paper presents a new Multi-Agent Artificial Immune Network （Ma-aiNet） algorithm, which combines immune mechanics and multiagent technology, to overcome the premature convergence problem in high-dimensional systems and to efficiently use the agent ability of sensing and acting on the environment. Ma-aiNet integrates global and local search algorithms. The perform- ance of the proposed method is evaluated using 10 benchmark problems, and the results are compared with other well-known intelligent algorithms. The study demonstrates that Ma-aiNet outperforms other algorithms tested. Ma-aiNet is also used to determine the Murphree efficiency of a distillation column with satisfactory results.

关键词： bio-inspired optimization multi-agent immune network distillation column Murphree efficiency

新型袢利尿剂托拉塞米在心衰患者临床治疗中的应用研究进展

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中国实用医药 2024年第14期19卷 178-180页

作者：冯春前赖晖明深圳市龙岗区第五人民医院内科 518000

心力衰竭(心衰)是指心脏功能不足,无法满足身体需要的一种疾病。袢利尿剂是一种利尿剂,可用于心衰患者的临床治疗。该药物可作用于肾小管上升段的升支粗段和细段,抑制钠、氯、镁和钙的重吸收,增加尿量和钠的排泄,以减轻心脏负荷。托拉... 详细信息

心力衰竭(心衰)是指心脏功能不足,无法满足身体需要的一种疾病。袢利尿剂是一种利尿剂,可用于心衰患者的临床治疗。该药物可作用于肾小管上升段的升支粗段和细段,抑制钠、氯、镁和钙的重吸收,增加尿量和钠的排泄,以减轻心脏负荷。托拉塞米是一种新型袢利尿剂,在心衰患者临床治疗中的应用效果备受关注,该药物是一种高效的袢利尿剂,与传统袢利尿剂相比,具有多方面优势但该药物的作用机制也更为复杂。如托拉塞米可作用于肾小管升支粗段的Na^(+)-K^(+)-2Cl^(-)共转运体(NKCC2)上,抑制Na^(+)-K^(+)-2Cl^(-)的重吸收,增加尿量和钠的排泄,以减轻心脏负荷。为此,本文就新型袢利尿剂托拉塞米在心衰患者临床治疗中的应用研究进展进行了综述。

关键词：新型袢利尿剂托拉塞米心力衰竭临床治疗应用研究进展

Sea surface wind speed retrieval from Sentinel-1 HH polarization data using conventional and neural network methods

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Acta Oceanologica Sinica 2021年第1期40卷 13-21页

作者： Tingting Qin Tong Jia qian feng Xiaoming Li College of Surveying Mapping and GeoinformationGuilin University of TechnologyGuilin 541006China Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100094China University of Chinese Academy of Sciences Beijing 101408China Key Laboratory of Space Ocean Remote Sensing and Applications National Satellite Ocean Application ServiceBeijing 100081China

Conventional retrieval and neural network methods are used simultaneously to retrieve sea surface wind speed(SSWS)from HH-polarized Sentinel-1(S1)SAR *** Polarization Ratio(PR)models combined with the CMOD5.N Geophysical Model Function(GMF)is used for SSWS retrieval from the HH-polarized SAR *** compared different PR models developed based on previous C-band SAR data in HH-polarization for their applications to the S1 SAR *** recently proposed CMODH,i.e.,retrieving SSWS directly from the HHpolarized S1 data is also *** results indicate that the CMODH model performs better than results achieved using the PR *** proposed a neural network method based on the backward propagation(BP)neural network to retrieve SSWS from the S1 HH-polarized *** SSWS retrieved using the BP neural network model agrees better with the buoy measurements and ASCAT dataset than the results achieved using the conventional *** to the buoy measurements,the bias,root mean square error(RMSE)and scatter index(SI)of wind speed retrieved by the BP neural network model are 0.10 m/s,1.38 m/s and 19.85%,respectively,while compared to the ASCAT dataset the three parameters of training set are–0.01 m/s,1.33 m/s and 15.10%,*** is suggested that the BP neural network model has a potential application in retrieving SSWS from Sentinel-1 images acquired at HH-polarization.

关键词： Sentinel-1 HH-polarization sea surface wind speed retrieval methods

A stochastic reconstruction strategy based on a stratified library of structural descriptors and its application in the molecular reconstruction of naphtha

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Chinese Journal of Chemical Engineering 2022年第11期51卷 153-167页

作者： Guangyao Zhao Minglei Yang Wenli Du Feifei Shen feng qian Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationEast China University of Science and TechnologyShanghai 200237China

Molecular reconstruction is a rapid and reliable way to provide molecular detail of petroleum fractions,which is required in the kinetic modeling of petroleum conversation processes at the molecular *** the typical stochastic reconstruction method,the estimation of properties of pseudo molecules that are generated by Monte Carlo sampling depends on the building of predefined molecular libraries,which is expensive and inaccessible for certain petroleum *** this paper,a novel stochastic reconstruction strategy is proposed,which is based on a stratified library of structural *** of pseudo molecules generated in the novel strategy can be directly estimated by group contribution method in the condition of lacking predefined molecular *** this strategy,the molecular building diagram comprises two ***,the ring structure is configured by determining the number of *** from the length of chain adopted in the traditional stochastic reconstruction method,in the second step,number of structural descriptors(SDs)for binding site and chain were determined sequentially for the configuration of binding site and saturated acyclic hydrocarbon *** structural descriptors for binding site and chain were selected from group contribution *** count the number of partial overlapping sections between structural descriptors for chain,two supplementary structural descriptors were *** possible saturated structures of hydrocarbon chains can be represented by structural descriptors at the scale of property *** strategy separates the building of a predefined molecule library from the stochastic reconstruction *** exact structures of pseudo molecules represented by structural descriptors in this work can be determined with sufficient chemical *** naphtha samples are tested independently to demonstrate the performance of the proposed strategy and the results show that the estimated prop

关键词： Novel stochastic reconstruction strategy Stratified library of structural descriptors Group contribution method

Multiple input self-organizing-map ResNet model for optimization of petroleum refinery conversion units

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Frontiers of Chemical Science and Engineering 2023年第6期17卷 759-771页

作者： Jiannan Zhu Vladimir Mahalec Chen Fan Minglei Yang feng qian Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationEast China University of Science and TechnologyShanghai 200237China Department of Chemical Engineering McMaster UniversityHamiltonOntario L8S 4L8Canada Engineering Research Center of Process System Engineering Ministry of EducationEast China University of Science and TechnologyShanghai 200237China

This work introduces a deep-learning network,i.e.,multi-input self-organizing-map ResNet(MISR),for modeling refining units comprised of two reactors and a separation *** model is comprised of self-organizing-map and the neural network *** self-organizing-map part maps the input data into multiple two-dimensional planes and sends them to the neural network *** the neural network part,residual blocks enhance the convergence and accuracy,ensuring that the structure will not be overfitted *** of the MISR model of hydrocracking unit also benefits from the utilization of prior knowledge of the importance of the input variables for predicting properties of the *** results show that the proposed MISR structure predicts more accurately the product yields and properties than the previously introduced self-organizing-map convolutional neural network model,thus leading to more accurate optimization of the hydrocracker ***,the MISR model has smoother error convergence than the previous *** operating conditions have been determined via multi-round-particle-swarm and differential evolution *** experiments show that the MISR model is suitable for modeling nonlinear conversion units which are often encountered in refining and petrochemical plants.

关键词： hydrocracking convolutional neural networks self-organizing map deep learning data-driven optimization