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Parameter selection for the hydroconversion of waste polyethylene plastic under mild conditions: A comprehensive evaluation

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Science China(Technological Sciences) 2024年第8期67卷 2413-2426页

作者： CHENG LeiLei CHEN RuiZhe ZHU WeiQiang tian shaonan GU Jing YUAN HaoRan CHEN Yong Guangzhou Institute of Energy Conversion Chinese Academy of SciencesGuangzhou 510640China School of Energy Science and Engineering University of Science and Technology of ChinaHefei 230026China Institute of Process Engineering Chinese Academy of SciencesBeijing 100190China

The hydrogenolysis/hydrocracking of waste polyethylene(PE) has recently been intensively studied, with the general pursuit of low-temperature reaction conditions, increased oil-phase yield, and narrower carbon chain distribution. Before this, we utilized a ball-milled ZSM-22 catalyst loaded with Ru nanoparticles(NPs), which exhibited excellent hydroconversion performance. It deconstructed PE into >80 wt.% oil products under low temperatures and short reaction times. Herein, we investigated the influence of varying temperature/pressure parameters on the degree of specific hydrocracking/internal hydrogenolysis/terminal hydrogenolysis reactions. From the comprehensive energy efficiency perspective, including stirring, reaction, and product separation, as well as taking into account the degree of product isomerization and catalyst lifespan, we analyzed the optimization of parameters. This research abandons the notion that lower temperatures are better and proposes a more comprehensive evaluation framework for low-consumption hydroconversion of PE to produce high-value products.

关键词： plastic upcycling polyethylene hydrocracking hydrogenolysis comprehensive energy efficiency

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稀土废渣中污染物特性及环境风险分析

中国稀土学报 2024年第1期42卷 168-178,I0006页

作者：郭凤田少囡吴玉锋中国科学院过程工程研究所模块化平台公共仪器中心北京100190 北京工业大学循环经济研究院北京100124

探究了离子型稀土矿开采产生的除杂渣、酸溶渣、熔盐渣3种典型稀土废渣的腐蚀性、组成、物相结构及赋存状态。基于典型稀土废渣的赋存状态及其堆存自然环境,研究了浸泡时间、浸泡液pH值和浸泡温度等因素对其所含铜、锌、铅、镉、镍、总... 详细信息

探究了离子型稀土矿开采产生的除杂渣、酸溶渣、熔盐渣3种典型稀土废渣的腐蚀性、组成、物相结构及赋存状态。基于典型稀土废渣的赋存状态及其堆存自然环境,研究了浸泡时间、浸泡液pH值和浸泡温度等因素对其所含铜、锌、铅、镉、镍、总铬、铍、钡、砷、硒等重金属离子及镝,铒,钆,钬,钕,镨,钐,镱稀土元素的浸出含量的影响,分析和评估了除杂渣、酸溶渣、熔盐渣3种典型稀土废渣的有毒重金属离子浸出毒性和环境风险,为稀土废渣的回收利用和安全处置提供了数据支撑。

关键词：除杂渣酸溶渣熔盐渣浸出毒性环境风险稀土

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船用单拉吊离式舱盖设计

科学技术创新 2024年第4期 72-75页

作者：田少男澳龙船艇科技有限公司广东中山

介绍了一种可以单拉开启,吊离开启,同时可以满足局部开启的一种货船风雨密舱口盖,本设计巧妙地运用连接链,压紧器,衔接器,限位器,偏心轮,导向轮等机械构件相互配合通过力学及运动轨迹分析实现舱盖的多种方案开启方式,此设计可以满足不... 详细信息

介绍了一种可以单拉开启,吊离开启,同时可以满足局部开启的一种货船风雨密舱口盖,本设计巧妙地运用连接链,压紧器,衔接器,限位器,偏心轮,导向轮等机械构件相互配合通过力学及运动轨迹分析实现舱盖的多种方案开启方式,此设计可以满足不同船东、不同用户、不同船型、不同位置开启舱盖的需求。

关键词：单拉吊离舱盖片体绞车

金属基磷化物纳米材料制备与电催化应用研究进展

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材料导报 2024年第8期38卷 1-17页

作者：刘卉杨牛娃马梦圆田少囡张玉杨军中国科学院过程工程研究所介科学与工程全国重点实验室北京100190 中国科学院大学材料科学与光电技术研究中心北京100049

处于纳米尺度的磷化物及其与贵金属构成的复合材料具有独特的物理和化学性质,在电催化领域有广泛应用。例如,在甲醇电催化氧化反应中,由于磷(P)比金属铂(Pt)或钯(Pd)等具有更大的电负性,金属原子的外层电子被P吸引而偏向P原子,从而间接... 详细信息

处于纳米尺度的磷化物及其与贵金属构成的复合材料具有独特的物理和化学性质,在电催化领域有广泛应用。例如,在甲醇电催化氧化反应中,由于磷(P)比金属铂(Pt)或钯(Pd)等具有更大的电负性,金属原子的外层电子被P吸引而偏向P原子,从而间接提高了Pt或Pd对CO类中间产物的耐受性;在电解水析氢反应中,P可以作为质子受体,增强H^(+)在金属上的吸附,从而促进析氢反应;在电解水析氧反应中,金属基磷化物容易被氧化成氧化物和氢氧化物,从而形成氧化物/氢氧化物-磷化物界面,进一步促进析氧反应。纳米颗粒的催化性能很大程度上取决于催化剂的结构、组分、组分之间的相互作用以及活性位点的电子结构,因此,对金属基磷化物基纳米复合材料的这些性质进行合理调控是提升其电催化性能的关键。本文所综述的材料范围包含金属基磷化物本身及其与贵金属构成的纳米复合材料,首先概括介绍金属基磷化物基纳米复合材料的合成方法和表征技术,进而阐述如何利用复合材料中晶格应变和电子耦合等物理效应提升电催化活性和稳定性。最后,围绕金属基磷化物基纳米复合材料电催化性能进一步提升的问题,对其未来合成策略和发展进行展望。

关键词：金属基磷化物纳米复合材料电催化甲醇氧化反应析氢反应析氧反应

Core-shell gold-copper nanoparticles:Evolution of copper shells on gold cores at different gold/copper precursor ratios

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Chinese Journal of Structural Chemistry 2023年第11期42卷 32-39页

作者： shaonan tian Yu Zhang Qing Zeng Junyu Zhong Hui Liu Lin Xu Jun Yang State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing100190China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049China State Key Laboratory of Bio-fibers and Eco-textiles Qingdao UniversityQingdao266071China School of Chemistry and Materials Science Jiangsu Key Laboratory of New Power BatteriesJiangsu Collaborative Innovation Centre of Biomedical Functional MaterialsNanjing Normal UniversityNanjing210023China

Core-shell nanostructures usually exhibit tunable catalytic properties in comparison with their single core or shell counterpart due to electronic interaction and lattice strain between the core and shell ***,we report the intriguing evolution of copper(Cu)shells on the gold(Au)cores at different Au/Cu precursor ratios during the synthesis of core-shell Au-Cu nanoparticles at an organic medium via seed-mediated growth *** brief,at relatively low Cu ratios,quasi-spherical Au-Cu nanoparticles with conventional core-shell structures are the majority products,in which the Cu shell thickness increases with the increase of Cu precursor *** dif-ference is that at high Cu ratios,the Cu shells no longer increase their thickness,but evolve into a dendritic ***,the core-shell Au-Cu nanoparticles with dendritic Cu shells could be transformed into interesting Au-Cu cage-bell structures after a ripening process at elevated ***,through galvanic replacement reaction with Pt precursors,the thin Cu shells could be converted into CuPt alloy shells on the Au cores,which exhibit enhanced activity towards methanol oxidation reaction with satisfactory durability,in comparison with that of commercial Pt/C catalysts.

关键词： Core-shell nanostructure Seed-mediated growth Electronic interaction Lattice strain Methanol oxidation reaction

A Blockchain-Based Access Control Scheme for Reputation Value Attributes of the Internet of Things

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Computers, Materials & Continua 2024年第1期78卷 1297-1310页

作者： Hongliang tian Junyuan tian College of Electrical Engineering Northeast Electric Power UniversityJilin132012China

The Internet of Things(IoT)access controlmechanism may encounter security issues such as single point of failure and data *** address these issues,a blockchain-based IoT reputation value attribute access control scheme is ***,writing the reputation value as an attribute into the access control policy,and then deploying the access control policy in the smart contract of the blockchain system can enable the system to provide more fine-grained access control;Secondly,storing a large amount of resources fromthe Internet of Things in Inter Planetary File System(IPFS)to improve system throughput;Finally,map resource access operations to qualification tokens to improve the performance of the access control *** simulation experiments based on the Hyperledger Fabric *** simulation experimental results,it can be seen that the access control system can achieve more fine-grained and dynamic access control while maintaining high throughput and low time delay,providing sufficient reliability and security for access control of IoT devices.

关键词： Blockchain IoT access control Hyperledger Fabric

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船舶船坞下水计算

广东造船 2017年第5期36卷 69-70页

作者：田少男广新海事重工股份有限公司中山528437

介绍了船舶在船坞下水中的稳性计算、受力分析及应对措施。

关键词：下水浮船计算

Robust adaptive radar beamforming based on iterative training sample selection using kurtosis of generalized inner product statistics

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Journal of Systems Engineering and Electronics 2024年第1期35卷 24-30页

作者： tian Jing ZHANG Wei School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China National Key Laboratory of Electromagnetic Space Security Chengdu 610036China

In engineering application,there is only one adaptive weights estimated by most of traditional early warning radars for adaptive interference suppression in a pulse reputation interval(PRI).Therefore,if the training samples used to calculate the weight vector does not contain the jamming,then the jamming cannot be removed by adaptive spatial *** the weight vector is constantly updated in the range dimension,the training data may contain target echo signals,resulting in signal cancellation *** cope with the situation that the training samples are contaminated by target signal,an iterative training sample selection method based on non-homogeneous detector(NHD)is proposed in this paper for updating the weight vector in entire range *** principle is presented,and the validity is proven by simulation results.

关键词： adaptive radar beamforming training sample selection non-homogeneous detector electronic jamming jamming suppression

Transformer and GAN-Based Super-Resolution Reconstruction Network for Medical Images

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Tsinghua Science and Technology 2024年第1期29卷 197-206页

作者： Weizhi Du Shihao tian Arts&Sciences College Washington University in St.LouisSt.LouisMO 63130USA Department of Electric and Computing Engineering Cornell UniversityIthacaNY 14850USA

Super-resolution reconstruction in medical imaging has become more demanding due to the necessity of obtaining high-quality images with minimal radiation dose,such as in low-field magnetic resonance imaging(MRI).However,image super-resolution reconstruction remains a difficult task because of the complexity and high textual requirements for diagnosis *** this paper,we offer a deep learning based strategy for reconstructing medical images from low resolutions utilizing Transformer and generative adversarial networks(T-GANs).The integrated system can extract more precise texture information and focus more on important locations through global image matching after successfully inserting Transformer into the generative adversarial network for picture ***,we weighted the combination of content loss,adversarial loss,and adversarial feature loss as the final multi-task loss function during the training of our proposed model *** comparison to established measures like peak signal-to-noise ratio(PSNR)and structural similarity index measure(SSIM),our suggested T-GAN achieves optimal performance and recovers more texture features in super-resolution reconstruction of MRI scanned images of the knees and belly.

关键词： super-resolution image reconstruction Transformer generative adversarial network(GAN)