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Journal of Thermal Science 2025年第1期 24-33页

作者： lin yongjie ZHANG Cancan WU Yuting ZHANG Yi LU Yuanwei Key Laboratory of Heat Transfer and Energy Conversion National User-Side Energy Storage Innovation Research and Development CenterBeijing University of Technology

Numerical simulations of the flow and heat transfer characteristics of four shell-and-tube molten salt electric heaters with different perforation rates was ***-and-tube electric heaters have the same geometry and tube arrangement,and all of them use single segmental baffles,but there exist four different baffle openings（φ）,i.e.,0%,2.52%,4.06%,and 6.31%.The results indicated that the reasonable baffle opening could significantly reduce the shell-side pressure drop,effectively decreasing the shell-side flow dead zone *** can eliminate the local high-temperature phenomenon on the surface of electric heating tubes,but the heat transfer coefficient is slightly *** perforated schemes significantly reduce shell-side pressure drop compared to the baseline solution without open *** particular,the φ=6.31% scheme exhibits the optimal performance among all the schemes,with a maximum reduction of up to 50.50% in shell-side pressure drop relative to the unopened holes *** heat transfer coefficient is the highest for φ=0%,exhibiting a range of5.26% to 5.73%,5.14% to 5.99%,and 7.31% to 8.54% higher than φ=2.52%,4.06%,and 6.31%,respectively,within the calculated *** composite index h/（Δp）1/3was higher for all open-hole solutions than that for the unopened-hole *** best overall performance was for φ=6.31%,which improved the composite index by15.29% to 17.18% over the unopened-hole solution.

关键词：

Effect of NaOH Treatment on Catalytic Performance of ZSM -5 in Cyclohexene Hydration

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Transactions of Tianjin University 2017年第1期23卷 43-50页

作者： Yaquan Wang Shougui Wang Fanjun Meng Shuhai Wang Jiaxin Ye yongjie lin Key Laboratory for Green Chemical Technology of the Ministry of Education School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China

ZSM-5 zeolite prepared by a hydrothermal method with the addition of seeds was treated with different concentrations of NaOH. The obtained samples were characterized by XRD, N2adsorption, NH3-TPD, FT-IR, SEM, and studied in the catalytic performance of the hydration of cyclohexene to cyclohexanol. The characterization results showed that with the increase of NaOH concentration, the crystallinity of the treated samples decreased monotonously, and the acid sites of ZSM-5 zeolites first increased and then decreased, while more mesopores formed inside the ZSM-5 zeolites. The experimental results of catalytic performance showed that cyclohexene conversion can be improved through introducing the mesopores and enhancing the acidity of ZSM-5 with the NaOH treatment at a low concentration. The highest cyclohexene conversion of 12.8% was obtained when the concentrations of NaOH solution were in the range of 0.2–0.6 mol/L. The selectivity of cyclohexanol on all samples was higher than 99.6%. © 2016, Tianjin University and Springer-Verlag Berlin Heidelberg.

关键词： Hydration Zeolites

Effect of TS-1 Treatment by Mixed Alkaline on Propylene Epoxidation

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Transactions of Tianjin University 2018年第1期24卷 25-31页

作者： Yaquan Wang Haoyang Li Wei Liu yongjie lin Xinpeng Han Zhao Wang Key Laboratory for Green Chemical Technology of the Ministry of Education School of Chemical Engineering and Technology Tianjin University

Titanium silicate-1(TS-1) was treated with a mixed alkaline of tetrapropyl ammonium hydroxide(TPAOH) and NaOH. It was characterized by XRD, nitrogen physical adsorption, SEM, FT-IR, UV-Vis and ICPOES, and studied in propylene epoxidation. The mixed alkaline treatment with TPAOH/NaOH solution did not destroy the MFI structure of TS-1. With increasing NaOH concentrations, the relative crystallinity and the framework titanium decreased to some extent while the mesopore volume, mesopore diameter, and extra-framework titanium increased appreciably. When NaOH concentration was 0.0333 mol L^(-1), the best catalytic performance was obtained.

关键词： TS-1 Mixed alkaline Catalytic performance Propylene epoxidation

Effects of the Amount of Tetrapropyl Ammonium Hydroxide in Synthesis on TS-1 Properties and Catalytic Performance in Epoxidation of Propylene

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Transactions of Tianjin University 2016年第5期22卷 458-465页

作者： Wang Yaquan Liu Wei lin yongjie Ye Jiaxin Wang Shuhai Li Haoyang Key Laboratory for Green Chemical Technology of the Ministry of Education School of Chemical Engineering and Technology Tianjin University

Titanium silicalite-1(TS-1) was synthesized by a hydrothermal synthesis method with different amounts of tetrapropyl ammonium hydroxide(TPAOH) as *** as-prepared TS-1 was characterized by scanning electron microscopy,X-ray powder diffraction,Fourier-transform infrared resonance spectroscopy,ultravioletvisible diffuse reflectance spectroscopy and nitrogen physical adsorption and desorption,and studied in the propylene epoxidation with hydrogen peroxide in a fixed bed *** results showed that the amount of TPAOH had a strong influence on the grain morphology,the amount of framework Ti,and the average particle sizes of *** the increase of TPAOH amount in the synthesis(the molar ratio of TPAOH/SiO_2 increasing from 0.25 to 0.45),the morphology changed gradually from ellipsoids to cubes,the particle sizes of TS-1 decreased slightly,the amount of the framework Ti increased appreciably,and the catalytic stability in the propylene epoxidation increased ***,all the catalysts had the same selectivity to propylene ***,when the molar ratio of TPAOH/SiO_2 was further increased to 0.55,the particles became large hexagons with the size distribution in a wide range,and the catalytic stability decreased sharply although the amount of the framework Ti increased further,which can be attributed to the long diffusion paths of the reactants in the zeolite.

关键词： TS-1 tetrapropyl ammonium hydroxide particle size framework Ti propylene epoxidation

Progress and Prospects of Salt Lake Research in China

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Acta Geologica Sinica(English Edition) 2016年第4期90卷 1195-1235页

作者： ZHENG Mianping ZHANG Yongsheng LIU Xifang NIE Zhen KONG Fanjing QI Wen Jia Qingxian PU linzhong HOU Xianhua WANG Hailei ZHANG Zhen KONG Weigang lin yongjie R&D Center for Saline Lake and Epithermal Deposit CAGS Key Laboratory of Saline Lake Resources and Environment Ministry of Land and Resources

China has unique salt lake resources, and they are distributed in the east of Eurasian salt lake subzone of the Northern Hemisphere Salt Lake Zone, mainly concentrated in the regions with modern mean annual precipitation lower than 500 mm. This paper preliminarily reviews the progress made in salt lake research in China for the past 60 years. In the research of Paleoclimate and paleoenvironment from salt lake sediments, a series of salts have been proposed to be indicators of paleoclimate, and have been well accepted by scholars. The chloride-sulfate depositional regions of the west Qaidam and the east Tarim have been revealed to be the drought center of China since the Quaternary, and more than 6 spreading stages of arid climate （salt forming） have been identified. Five pan-lake periods with highstands have been proved to exist during the late Quaternary on the Tibetan Plateau. In mineral resource prospecting and theories of the forming of salt deposits： the atlas （1：2500000） of hydrochemical zoning of salt lakes on the Tibetan Plateau has been compiled for the first time, revealing the zonal distribution and transition from carbonate type to chloride type from south to north and presenting corresponding mineral assemblages for different type of salt lakes; several large continental salt deposits have been discovered and the theory of continental potash deposition has been developed, including the salt deposition in deep basins surrounded by high mountains, the mineral deposition from multistage evolution through chains of moderate or shallow lakes with multilevels, the origin of potassium rich brines in gravel layers, and the forming of potassium deposits through the inheriting from ancient salt deposits, thus establishing the framework of ＂Continental Potash Deposition Theory＂; several new types of Mg-borate deposits have been discovered, including the ulexite and pinnoite bed in Da Qaidam Lake, Qinghai, the pinnoite and kurnakovite bed in Chagcam Caka, Tibet, th

关键词： progress in salt lake research in China salt lake deposits and paleoclimate salt deposition mineralization and salting theory of saline lakes utilization and exploitation salt lake agriculture

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基于毫米波雷达点云的路口车辆轨迹跟踪方法

华南理工大学学报（自然科学版） 2023年第10期51卷 110-125页

作者：林永杰陈宁卢凯华南理工大学土木与交通学院广东广州510640 人工智能与数字经济广东省实验室(广州) 广东广州510330

毫米波雷达作为一种新兴的交通检测设备,受光照、天气等环境影响较小,能为道路交通感知、安全管控和信号配时优化等方面提供可靠的数据支撑。毫米波雷达获取的车辆轨迹数据蕴含着丰富的交通信息,反映了车辆时空运动特征,对交通参数提取... 详细信息

毫米波雷达作为一种新兴的交通检测设备,受光照、天气等环境影响较小,能为道路交通感知、安全管控和信号配时优化等方面提供可靠的数据支撑。毫米波雷达获取的车辆轨迹数据蕴含着丰富的交通信息,反映了车辆时空运动特征,对交通参数提取、事件检测、驾驶行为分析、信号配时优化等具有重要意义。针对路口毫米波雷达检测车辆时数据丢失、易被遮挡,导致轨迹碎片化、有效跟踪率低等问题,文章采用多阶段关联的思想提出了一种基于短轨迹片段关联的车辆轨迹连续跟踪方法。首先,获取路口处毫米波雷达高频采集的二维点云数据,并进行清洗获取有效目标点云;其次,通过帧间关联从二维点云中提取短轨迹片段,并使用多重运动序列特征进行轨迹片段修正以剔除分裂轨迹;第三,基于时空维度的运动特性构建模糊相关函数描述车辆经过路口时多个短轨迹碎片之间的相关度,并利用匈牙利法求解关联度最高的构成目标短轨迹集合;最后,基于三次分段Hermite插值法修复短轨迹集合中缺失的轨迹点,推算完整轨迹并实现连续跟踪。利用真实路口采集的6627帧二维点云数据进行试验,其结果表明:相较于传统轨迹跟踪算法,提出的方法在不同车流密度、监测方向和遮挡情况下均能取得较优的跟踪性能,其跟踪准确性为92.4%,平均轨迹间断数为4.5条,估计的车辆数准确率显著提升。

关键词：交通检测车辆轨迹跟踪毫米波雷达短轨迹关联模糊相关函数

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青藏高原盐湖反风化作用与关键元素循环

地球学报 2024年第5期45卷 777-790页

作者：林勇杰郑绵平中国地质科学院矿产资源研究所、自然资源部盐湖资源与环境重点实验室北京100037

盐湖环境中的反风化(reverse weathering,又称逆风化)是指逆向的化学风化作用,通常指盐湖内部自生黏土矿物或碳酸盐矿物的形成过程,是控制盐湖关键元素地球化学循环的重要机制。青藏高原是地球上关键的盐湖区,既是内陆生态系统重要的碳... 详细信息

盐湖环境中的反风化(reverse weathering,又称逆风化)是指逆向的化学风化作用,通常指盐湖内部自生黏土矿物或碳酸盐矿物的形成过程,是控制盐湖关键元素地球化学循环的重要机制。青藏高原是地球上关键的盐湖区,既是内陆生态系统重要的碳库,又富含锂、钾、铷、铯等关键矿产资源。青藏高原盐湖的水化学类型多样,包括碳酸盐型、硫酸盐型和氯化物型,不同的水化学特征决定了盐类和黏土矿物的种类及其形成机制的差异。本文综述了盐湖环境中硅酸盐和碳酸盐反风化作用的研究进展,并探讨青藏高原盐湖反风化作用对关键元素地球化学循环的影响。青藏高原盐湖中自生黏土矿物的形成(如伊利石)是对盐湖卤水锂、钾、铷、铯等关键元素最重要的消耗机制;而碳酸盐的形成对关键金属元素消耗影响很小,除非形成含关键金属元素的独立矿物,如扎布耶石。自生黏土矿物和碳酸盐的形成均会显著影响湖泊的无机碳循环。目前,盐湖反风化作用程度的量化、控制因素解析和对关键元素损耗的影响程度是盐湖矿产资源研究的关键问题。当前非传统稳定同位素技术的快速发展为盐湖反风化研究提供了新机遇。青藏高原盐湖是反风化研究的天然实验室,开展盐湖反风化研究不仅可以深入理解青藏高原盐湖的关键金属元素成矿作用及碳循环过程,而且有助于丰富反风化理论。

关键词：盐湖反风化作用关键金属元素循环碳循环青藏高原

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基于S变换双阈值法的汽车零部件载荷谱加速编辑

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中国机械工程 2024年第2期35卷 215-220页

作者：姚凌云林勇杰李丽西南大学工程技术学院重庆400715 丘陵山区农业装备重庆市重点实验室重庆400715

针对S变换编辑法加速编辑效果不佳的问题,提出了一种基于S变换双阈值编辑方法。该方法先对载荷谱进行S变换以获取最大幅值谱,在以双阈值识别并保留的幅值谱片段为依据保留对应的载荷谱片段后,再将其拼接成加速后的载荷谱,最后对比分析S... 详细信息

针对S变换编辑法加速编辑效果不佳的问题,提出了一种基于S变换双阈值编辑方法。该方法先对载荷谱进行S变换以获取最大幅值谱,在以双阈值识别并保留的幅值谱片段为依据保留对应的载荷谱片段后,再将其拼接成加速后的载荷谱,最后对比分析S变换双阈值编辑法与S变换编辑法编辑的加速谱的统计参数、功率谱密度、穿级计数和疲劳仿真结果。研究结果表明,S变换双阈值编辑法可明显压缩原始载荷时间,且其压缩效率高于S变换编辑法,转向节的疲劳损伤和寿命分析误差更小,适用于汽车零部件载荷谱加速编辑研究。

关键词： S变换最大幅值谱双阈值疲劳计算载荷谱加速编辑

Synthesis of Mesoporous Titanium Silicalite-1 with High Stability in Cyclohexanone Ammoximation

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Transactions of Tianjin University 2016年第3期22卷 254-260页

作者：王亚权叶家鑫王书海林永杰王守桂刘伟 Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and Technology Tianjin University

Mesoporous titanium silicalite-1(TS-1)was hydrothermally synthesized with the addition of triethanolamine(TEA)in the conventional process, and used in the cyclohexanone ammoximation in a continuous slurry reactor. The as-prepared TS-1 was characterized with X-ray diffraction(XRD), scanning electron microcopy(SEM), N_2 adsorption-desorption, Fourier transform infrared(FT-IR)spectroscopy, UV-Visible(UV-Vis)diffuse reflectance spectra and UV Raman spectroscopy. The results indicated that the addition of TEA resulted in the formation of mesopores and the slight increase of framework titanium in TS-1. TS-1 synthesized with the addition of TEA exhibited a higher stability in the cyclohexanone ammoximation than that without the addition of TEA, attributing to the increase of mesopore volumes and the slight increase of the framework titanium in TS-1. However, when the addition of TEA was up to TEA/SiO_2 ratio of 0.24, the crystallinity and framework titanium of TS-1 decreased markedly, and the average crystal sizes of TS-1 increased, with the catalyst stability becoming poor.

关键词： TS-1 triethanolamine cyclohexanone ammoximation mesopore stability

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基于梯度提升决策树的城市车辆路径链重构

华南理工大学学报（自然科学版） 2020年第7期48卷 55-64页

作者：徐建闽魏鑫林永杰卢凯华南理工大学土木与交通学院广东广州510640

为了提取城市路网中车辆实际的行驶轨迹,支撑交通规划、设计、管理和评价等需求,提出了基于梯度提升决策树的城市车辆丢失路径链的重构方法。首先,根据车牌号码匹配目标车辆,以时间排序提取视频检测器获得的路径链,并结合交叉口邻接矩... 详细信息

为了提取城市路网中车辆实际的行驶轨迹,支撑交通规划、设计、管理和评价等需求,提出了基于梯度提升决策树的城市车辆丢失路径链的重构方法。首先,根据车牌号码匹配目标车辆,以时间排序提取视频检测器获得的路径链,并结合交叉口邻接矩阵及路段行程时间估计进行路径链初次分离;然后,依据车辆出行特征和交通状况提取影响路径选择的关键特征,并基于此提出了基于梯度提升决策树的局部丢失路径链重构算法;最后,以某市南明区实际视频车牌识别数据为例,根据重构算法准确性和计算效率验证了文中算法与传统算法。结果表明,本文算法的重构准确率达到91%,对比传统算法,梯度提升决策树算法在车辆路径链重构方面有较大优势。

关键词：梯度提升决策树城市道路网络车牌识别路径链分离路径链重构