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Chinese Chemical Letters 2024年第4期35卷 393-398页

作者： Jun Lu Jinrui Yan Yaohao Guo junjie qiu Shuangliang Zhao Bo Bao East China University of Science and Technology Shanghai 200237China Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology and School of Chemistry and Chemical Engineering Guangxi UniversityNanning 530004China

Crystal habit and crystal form are critical elements in determining product properties and functions. In this work, we developed a microfluidic antisolvent crystallization technique to rapidly screen and accurately control the solid form and crystal habit of triphenylmethanol(Ph_(3)COH). This advanced technique separates the primary mixing of solutions from crystal formation(nucleation and growth) by introducing the microfluidic device, avoiding clogging in microchannels to obtain high-quality crystals. The results show that we can achieve controllable preparation of pure 2Ph_(3)COH·DMSO(DMSO solvate), pure Ph_(3)COH(form β), and mixed crystals with different mass ratios. Moreover, the microscale can prompt the DMSO solvate to grow into hexagonal sheet-like and bulk crystals. We can regulate the aspect ratio of hexagonal sheet-like crystals in binary solvents and control the crystal habit of the form β to transition between long needle-like shapes and short hexagonal prisms in DMF-H_(2)O. Meanwhile, we revealed that the solvent ratio, the antisolvent flow rate, and the initial concentration of Ph_(3)COH are the main factors affecting the solid form selectivity and morphology transition. Such a novel method would be considered as a promising technique to be extended to screen and control key crystallization parameters of other substances.

关键词： Microfluidics Triphenylmethanol Antisolvent crystallization Crystal habit Solid form

融合Transformer的剩余使用寿命预测模型

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应用科学学报 2024年第5期42卷 847-856页

作者：郑红刘文邱俊杰余金浩华东理工大学信息科学与工程学院上海200237

剩余使用寿命(remaining useful life,RUL)预测对大型设备的故障预测与健康管理十分重要。然而,一些设备监测数据具有维度高、规模大、强耦合、参数时变等非线性特征,这些特征会导致RUL预测的准确性较低。为此引入Transformer解码器,并... 详细信息

剩余使用寿命(remaining useful life,RUL)预测对大型设备的故障预测与健康管理十分重要。然而,一些设备监测数据具有维度高、规模大、强耦合、参数时变等非线性特征,这些特征会导致RUL预测的准确性较低。为此引入Transformer解码器,并通过多头注意力机制综合全局信息,提出了一种基于多尺度双向长短期记忆网络和Transformer的神经网络模型,以提高模型预测精度。选取航空发动机作为研究对象,使用各个模型在NASA的C-MPASS数据集上进行对比实验,结果表明,在剩余使用寿命预测方面,该文提出的融合Transformer模型的多尺度双向长短期记忆网络模型在准确率和均方根误差指标上均优于其他对比模型。

关键词：剩余使用寿命故障预测与健康管理双向长短期记忆网络 Transformer

劳动力老龄化及其认知对农业生产性服务外包采纳行为的影响

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中国农业资源与区划 2024年第8期45卷 242-253页

作者：陈政通许彩华邱俊杰余劲西北农林科技大学经济管理学院长安大学经济与管理学院

[目的]根据冀鲁豫粮食主产区的实地调研数据，基于认知行为理论的基本内容，研究老龄化背景下农户的服务外包采纳行为是否受到其对耕地的生计保障、情感寄托和财产享益功能认知的影响。[方法]文章运用Ordered probit模型、二元Probit模... 详细信息

[目的]根据冀鲁豫粮食主产区的实地调研数据，基于认知行为理论的基本内容，研究老龄化背景下农户的服务外包采纳行为是否受到其对耕地的生计保障、情感寄托和财产享益功能认知的影响。[方法]文章运用Ordered probit模型、二元Probit模型以及中介效应模型分析其影响机制。[结果]（1）农业劳动力老龄化对服务外包采纳行为呈显著负向影响，已有大多研究结论的正向影响实际上是农户主观耕地功能认知“遮掩效应”的表现；（2） 60岁以上农户的服务外包采纳行为受到其对耕地生计保障和财产享益功能认知的中介作用影响；（3） 65岁以上农户的服务外包采纳行为受到其对耕地财产享益功能认知的中介作用影响。[结论]为有效提升老龄化背景下粮食主产区生产性服务外包采纳率，首先，政府部门应该增强服务外包可达性、信息服务及资金支持范围。其次，吸引年轻劳动力回流农业，改善人力资本结构。最后，加大对农村经济的扶持力度，引导和鼓励农村老龄农户发展特色农业、绿色农业等高附加值农业产业，为老龄农户提供更多培训机会，降低老龄农户对耕地生计保障和财产享益功能的认知水平。

关键词：老龄化耕地功能认知服务外包采纳行为中介效应遮掩效应

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一种高性能功率放大器-圆极化天线的一体化设计

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微波学报 2024年第1期40卷 34-38,59页

作者：邱俊杰尤阳陆云龙黄季甫宁波大学信息科学与工程学院宁波315211

本文设计了一种具有圆极化辐射特性的高性能功率放大器-天线一体化电路。通过直接优化圆极化天线的输入阻抗,使之与消除输出匹配网络的功放电路直接集成。这种无缝集成方式不仅有效减少了插入和失配损耗以及整体电路尺寸,而且提高了整... 详细信息

本文设计了一种具有圆极化辐射特性的高性能功率放大器-天线一体化电路。通过直接优化圆极化天线的输入阻抗,使之与消除输出匹配网络的功放电路直接集成。这种无缝集成方式不仅有效减少了插入和失配损耗以及整体电路尺寸,而且提高了整体的性能。采用的圆极化天线由矩形贴片和改进的地平面组成,通过在地平面上增加垂直短截线和切割水平缝隙,增强了天线的3 dB轴比带宽。为了验证,设计、制造和测量了工作在3.4 GHz~3.6 GHz的一体化电路原型。实验结果显示,功放-圆极化天线一体化电路在工作频带内的功率附加效率(PAE)超过60%,且3 dB轴比带宽达到320 MHz(相对于3500 MHz的中心频率为9.1%)。相较于传统的级联设计,PAE提高了8.5%,3 dB轴比带宽也得以改善。

关键词：功放-圆极化天线一体化圆极化天线功率附加效率轴比带宽

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我国垃圾填埋碳排放核算标准的编制建议

中国工程科学 2024年第2期26卷 174-184页

作者：何品晶李晓静吕凡仇俊杰廖南林章骅同济大学环境科学与工程学院上海200092 上海污染控制与生态安全研究院上海200092

填埋作为我国主要的垃圾处理方式之一,是碳排放的重要来源;编制我国垃圾填埋碳排放核算标准,将支持碳排放统计核算体系建设,推进碳达峰、碳中和目标进程。本文梳理了国内外垃圾填埋碳排放核算的相关标准和指南研制进展,分析了我国垃圾... 详细信息

填埋作为我国主要的垃圾处理方式之一,是碳排放的重要来源;编制我国垃圾填埋碳排放核算标准,将支持碳排放统计核算体系建设,推进碳达峰、碳中和目标进程。本文梳理了国内外垃圾填埋碳排放核算的相关标准和指南研制进展,分析了我国垃圾填埋碳排放核算标准编制面临的挑战,在深入讨论相关标准的基准方法、编制重点任务的基础上提出了有关发展建议。研究认为,国际上已有的标准和指南以及提供的缺省值不完全适用于我国垃圾填埋碳排放核算的实际情况,目前我国缺少规范统一的垃圾填埋碳排放核算方法,也缺乏可靠的核算清单数据。为此,针对我国填埋垃圾特征和技术现状,提出了我国垃圾填埋碳排放核算方法、核算范围和清单的建议内容;明晰了我国垃圾填埋碳排放核算标准编制的重点任务,提供了适合我国垃圾填埋场景的清单数据获取方式。后续,可充分考虑地区因素,采用我国特征性数据,以获得更贴合实际情况的垃圾填埋碳排放核算结果,据此开展我国垃圾填埋碳排放核算标准的编制工作。

关键词：垃圾填埋碳排放标准核算方法清单数据

Continuous synthesis of dolutegravir sodium crystals using liquid-gas heterogeneous microreactor

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Chinese Chemical Letters 2023年第3期34卷 302-307页

作者： Wei Luo Fen Liu Yaohao Guo junjie qiu Jinrui Yan Shuangliang Zhao Bo Bao State Key Laboratory of Chemical Engineering and School of Chemical Engineering East China University of Science and TechnologyShanghai 200237China Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology and School of Chemistry and Chemical Engineering Guangxi UniversityNanning 530004China

In this work, a liquid-gas heterogeneous microreactor was developed for investigating continuous crystallization of dolutegravir sodium(DTG), as well as revealing reaction kinetics and mixing mechanism with 3-min data acquisition. The reaction kinetics models were established by visually recording the concentration variation of reactants over time in the microchannel via adding pH-sensitive fluorescent dye. The mixing intensification mechanism of liquid-gas flow was quantified through the fluorescent signal to indicate mixing process, demonstrating an outstanding mixing performance with a mixing time less than 0.1 s. Compared with batch crystallization, continuous synthesis of dolutegravir sodium using liquid-gas heterogenous microreactor optimizes crystal distribution size, and successfully modifies the crystal morphology in needle-like habit instead of rod-like habit. The microreactor continuous crystallization can run for 5 h without crystal blockage and achieve D90 of DTG less than 30 μm. This work provides a feasible approach for continuously synthesizing dolutegravir sodium, and can optimize the existing pharmaceutical crystallization.

关键词： Microreactor continuous crystallization Dolutegravir sodium Reaction kinetics Mixing mechanism Crystal morphology Process operation

Molecular behavior and interactions with microbes during anaerobic degradation of bio-derived DOM in waste leachate

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Journal of Environmental Sciences 2023年第4期126卷 174-183页

作者： junjie qiu Tianqi Li Fan Lü Yulong Huang Chao Li Hua Zhang Liming Shao Pinjing He Institute of Waste Treatment and Reclamation Tongji UniversityShanghai 200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China Shanghai Engineering Research Center of Multi-source Solid Wastes Co-Processing and Energy Utilization Shanghai 200092China

It is the key to control bio-derived dissolved organic matters (DOM) in order to reduce the effluent concentration of wastewater treatment, especially for waste leachate with high organic contaminants. In the present study, the anaerobic degradation of aerobically stabilized DOM was investigated with DOM substrate isolated through electrodialysis. The degradation of bio-derived DOM was confirmed by reduction of 15%of total organic carbon in 100 *** characterized the molecular behavior of bio-derived DOM by coupling molecular and biological information analysis. Venn based Sankey diagram of mass features showed the transformation of bio-derived DOM mass features. Occurrence frequency analysis divided mass features into six categories so as to distinguish the fates of intermediate metabolites and persistent compounds. Reactivity continuum model and machine learning technologies realized the semi-quantitative determination on the kinetics of DOM mass features in the form of pseudo-first order, and confirmed the reduction of inert mass features. Furthermore, network analysis statistically establish relationship between DOM mass features and microbes to identify the active microbes that are able to utilize bio-derived DOM. This work confirmed the biological technology is still effective in controlling recalcitrant bio-derived DOM during wastewater treatment.

关键词： Soluble microbial products Data mining Machine learning Solid waste Orbitrap

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经验模态分解和近似熵下的隔离开关失效预警

自动化与仪器仪表 2024年第9期 186-189+194页

作者：邱俊捷鲍鹏飞王慧琴江健武深圳供电局有限公司

拥有隔离开关的设备由于大多具有封闭性，难以直观地确认其隔离开关和接地开关的位置状态，通常通过辅助开关发出的二次分合闸信号来判断其内部是否失效。一旦辅助开关位置信号出现误差，影响对隔离开关失效状态的判断。提出一种考虑信... 详细信息

拥有隔离开关的设备由于大多具有封闭性，难以直观地确认其隔离开关和接地开关的位置状态，通常通过辅助开关发出的二次分合闸信号来判断其内部是否失效。一旦辅助开关位置信号出现误差，影响对隔离开关失效状态的判断。提出一种考虑信号特征的隔离开关失效自动化预警方法。通过改进小波去噪阈值函数来处理隔离开关振动信号，以降低噪声影响。通过集合经验模态分解和近似熵提取振动信号特征，生成多维特征向量。为了降低维度并保留有效信息，使用核主成分分析对多维特征向量进行降维。采用支持向量机建立失效自动化预警模型，根据特征向量预测传动链的失效情况。实现隔离开关失效自动化预警。实验结果表明，所提方法预警正确率高、漏检率和虚警率低且计算时间短。

关键词：信号特征隔离开关机械传动链失效预警集合经验模态分解

A Bitcoin Address Multi-Classification Mechanism Based on Bipartite Graph-Based Maximization Consensus

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 783-800页

作者： Lejun Zhang junjie Zhang Kentaroh Toyoda Yuan Liu Jing qiu Zhihong Tian Ran Guo College of Information Engineering Yangzhou UniversityYangzhou225127China Cyberspace Institute Advanced Technology Guangzhou UniversityGuangzhou510006China Research and Development Center for E-Learning Ministry of EducationBeijing100039China Institute of High Performance Computing(IHPC) Agency for ScienceTechnology and Research(A∗STAR)Singapore138632Singapore School of Physics and Materials Science Guangzhou UniversityGuangzhou510006China

Bitcoin is widely used as the most classic electronic currency for various electronic services such as exchanges,gambling,marketplaces,and also scams such as high-yield investment *** the services operated by a Bitcoin address can help determine the risk level of that address and build an alert model *** engineering can also be used to flesh out labeled addresses and to analyze the current state of Bitcoin in a small *** this paper,we address the problem of identifying multiple classes of Bitcoin services,and for the poor classification of individual addresses that do not have significant features,we propose a Bitcoin address identification scheme based on joint multi-model prediction using the mapping relationship between addresses and *** innovation of the method is to(1)Extract as many valuable features as possible when an address is given to facilitate the multi-class service identification task.(2)Unlike the general supervised model approach,this paper proposes a joint prediction scheme for multiple learners based on address-entity mapping ***,after obtaining the overall features,the address classification and entity clustering tasks are performed separately,and the results are subjected to graph-basedmaximization *** final result ismade to baseline the individual address classification results while satisfying the constraint of having similarly behaving entities as far as *** testing and evaluating over 26,000 Bitcoin addresses,our feature extraction method captures more useful *** addition,the combined multi-learner model obtained results that exceeded the baseline classifier reaching an accuracy of 77.4%.

关键词： Bitcoin multi-service classification graph maximization consensus data security

Phase equilibria relations in the V_(2)O_(5)-rich part of the Fe_(2)O_(3-)TiO_(2)-V_(2)O_(5) system at 1200℃ related to converter vanadium-bearing slag

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International Journal of Minerals,Metallurgy and Materials 2024年第9期31卷 2017-2024页

作者： junjie Shi Yumo Zhai Yuchao qiu Changle Hou Jingjing Dong Maoxi Yao Haolun Li Yongrong Zhou Jianzhong Li Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China

The efficient recycling of vanadium from converter vanadium-bearing slag is highly significant for sustainable development and circular *** key to developing novel processes and improving traditional routes lies in the thermodynamic *** this study,the equilibrium phase relations for the Fe_(2)O_(3)-TiO_(2)-V_(2)O_(5)system at 1200℃in air were investigated using a high-temperature equilibrium-quenching technique,followed by analysis using scanning electron microscopy-energy dispersive X-ray spectrometer and X-ray photoelectron *** liquid-phase region,two two-phase regions(liquid-rutile and liquid-ferropseudobrookite),and one three-phase region(liquid-rutile-ferropseudobrookite)were *** variation in the TiO_(2)and V_(2)O_(5)contents with the Fe_(2)O_(3)content was examined for rutile and ferropseudobrookite solid ***,on further comparison with the predictions of FactSage 8.1,significant discrepancies were identified,highlighting that greater attention must be paid to updating the current thermodynamic database related to vanadium-bearing slag systems.

关键词： vanadium-bearing slag thermodynamics FactSage phase equilibria recovery